JP2001212899A - Decomposable highly water-absorbing composite - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sanitary article which is thin and has biodegradability and excellent water absorbing performance, and which can be treated by composting or laying underground. SOLUTION: A crosslinked polyamino acid resin is added to an absorbing core, and a microfibril cellulose is coated on a part or all of the surface of the resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a degradable superabsorbent composite. In detail, due to the structure of the pulp press, it is extremely thin while exhibiting excellent absorption characteristics when used, and can be easily disposed of by disposal in a flush toilet, composting, landfill, etc. at the time of disposal, and is biodegraded after processing And a degradable superabsorbent composite that is environmentally friendly.

[0002]

2. Description of the Related Art [Technical background of disposable hygiene articles] Disposable hygiene articles are articles designed to efficiently absorb bodily fluids such as urine, blood, menstrual blood, and sweat.
It is used for sanitary napkins, incontinence pads, breast milk pads, medical underpads, surgical underpads, pet seats and the like.

[0003] Such sanitary articles have the advantage that they are inexpensive and can be easily used, but there is a major problem in the disposal treatment after use, despite their widespread use in the world. That is, such a problem is that used sanitary articles such as disposable diapers to which excrement adheres and sanitary napkins to which body fluid adheres are discarded at the same time as general waste.

[Technical background of disposal of disposable hygiene articles] Generally, disposable hygiene articles are made to be disposed of after use. At present, they are discarded after use and incinerated as general combustible waste.

[0005] For example, the disposal method of disposable disposable diapers is as follows.
The disposable diapers are rounded so as to enclose the waste, and the rolled diapers are fastened with tape fasteners and discarded in a trash box, and the collected garbage is incinerated. General.

However, storing excrement wrapped in a disposable diaper in a trash can or the like for a short period of time is not preferable because of bad smell and hygiene problems. Also, even outside the room, for example, disposable disposable diapers are left as garbage in parks, etc.
Environmental health problems are occurring.

On the other hand, when the excrement is stool at the time of use, a method of disposing the disposable disposable diaper by a user or a caregiver removes the disposable diaper from the user and removes a solid portion of excrement such as stool from the disposable diaper. After removing and flushing the toilet, the other part is generally treated as general garbage, so that the operation is very complicated. In addition, since such treatment is usually performed by placing a disposable disposable diaper on a toilet bowl and running it down, loose stool or other sticky stool is difficult to peel off from the diaper, and the stool may not be completely removed and may be treated. Many. Therefore, an operation of removing the stool from the diaper may stain the hands of the processor, and in such a case, the essential merits of the disposable paper diaper are reduced as compared with a non-disposable diaper.

In addition, during such treatment, the disposable disposable diaper absorbs water from the toilet and becomes heavy, and causes dripping. In addition, the disposable diaper may accidentally flow into the toilet and clog the water distribution pipe. There are inconveniences.

Further, absorbent pads used by women, such as sanitary and vaginal napkins and diapers, are discarded after being wrapped in paper in a garbage container or a filth container placed in a toilet after use. It is.

[0010] However, there is a case where an unpleasant odor is generated and unpleasant or unsanitary during a lapse of time from disposal to disposal as garbage.

Further, in a public toilet or the like, the flush toilet flushes with water, causing a trouble such as clogging of a pipe.

[Technical Background of Incineration of Disposable Sanitary Ware Waste] Disposable sanitary ware waste is contained in a topsheet made of a nonwoven fabric or a porous molded polyethylene film or polypropylene film material, a backsheet made of polyethylene, and pulp. It is composed mainly of an absorbent core in which a water absorbent resin is dispersed. In these materials,
In particular, since a synthetic resin or synthetic fiber such as polyester, polypropylene, or polyethylene is partially used to maintain waterproofness, the back sheet does not have degradability. Even if these are disposed of by landfill or the like, they remain without being decomposed forever. Similarly, when flushed into a flush toilet, even if there is no clogging in a pipe or the like, such waste and the like remains without being decomposed at a terminal treatment plant or the like.
Therefore, despite the large amount of these wastes, they have to be treated by incineration at present.

[0013] That is, the used waste of the above-mentioned sanitary materials accounts for several percent of the total waste in terms of weight, but since these disposable sanitary materials do not have degradability, they are not disposed after use. It is a problem.

The problem with the prior art is that, for example, in the method of treating these wastes in an incinerator, the synthetic resin or synthetic fiber to be incinerated has a large heat of combustion and is generated during incineration due to high temperatures. In addition to damaging furnace materials due to the heat generated, it has also been pointed out that exhaust gases can cause global warming and acid rain.

On the other hand, it has been pointed out that the cause of the generation of dioxin from an incinerator is caused by incomplete combustion of a substance containing carbon and chlorine at a low temperature. In particular, diaper waste contains carbon and chloride salts,
Since the latent heat of vaporization is large and contains a large amount of hard-to-burn water,
It may not be possible to raise the incinerator incineration temperature locally or globally.

From the viewpoint of suppressing the generation of dioxin, even if the disposable diaper constituting material itself is not a direct cause of the generation of dioxin, at the stage of disposal,
Since disposable diapers contain salt and the temperature inside the incinerator can temporarily drop, it is necessary to review the disposal method.

In the method of landfill, the non-decomposable plastic constituting disposable diaper waste is:
In addition to the problem that the ground is not stable because the volume is bulky and does not rot, especially in Japan,
A major problem is that landfill sites are becoming scarce.

In order to solve such a problem, it has been proposed to use a part of the constituent materials of the sanitary material as a degradable material. For example, Japanese Patent Publication No. 5-505318 proposes to use a film made of a polymer having a dioxane-based backsheet. However, even if only a part of the constituent materials is decomposed, it will not be a fundamental solution of the disposal process unless other materials are decomposed. On the contrary, accumulation of undecomposed components is expected to become a problem. .

[Technical Background of Thinning Disposable Sanitary Ware] The main components of absorbent used in absorbent products for absorbing moisture and body fluids are fluffy wood pulp and so-called polymer absorbents ( Hereinafter, abbreviated as “SAP”). However, in recent years,
Social demands for thinner and more compact existing relatively bulky absorbent products to improve logistics efficiency, improve shelf efficiency at retail stores, and save resources. Is getting bigger.

As means for compactness and thinning, S means
In the combination of AP and pulp, 2 to 2
Increasing the ratio of SAP, which has about 10 times higher water absorption capacity, and decreasing the ratio of pulp will make it thinner and more compact. Ultimately, a 100% SAP structure will pursue maximum thinness and compactness. It should be possible.

However, as the SAP ratio increases,
In the case of water absorption, based on the properties of SAP,
Since the “gel blocking phenomenon” occurs and the absorbent product does not function with a calculation efficiency, the configuration of SAP / pulp = 1/1 is limited in the conventional technology, and SAP / pulp = ( 3/1) or more = 3 or more, and further, it is an extremely difficult technical problem to increase the SAP ratio and take a pulp press structure close to 100% SAP.

Here, the term "pulpless" is used according to a concept generally applied in this field.
The ratio of AP to pulp (SAP / pulp) is used as a generic term for one or more.

Of course, there have been various challenges regarding the pulp press structure. For example, a method of producing a fibrous, web-like SAP sheet by direct spinning or partial hydrolysis of an acrylic acid-based fiber, impregnating a web with a monomer such as acrylic acid, and polymerizing it with ultraviolet light or an electron beam. Various attempts have been made such as a method of producing a web-like water-absorbing polymer, or a method of producing a sheet-like water-absorbing polymer by carboxymethylating a nonwoven fabric such as cellulose and then partially cross-linking the same.

However, there has been no report of an industrially and economically successful case due to the problem of material cost and a large amount of capital investment.

[Technical Background of Water Absorbent Resin] A water absorbent resin is a resin capable of absorbing water of several tens to several thousand times its own weight, and is used for sanitary articles such as sanitary articles, disposable diapers, breast milk pads, disposable rags, and the like. Dressing materials for wound protection, medical underpads, medical supplies such as cataplasms, pet sheets, portable toilets, gel fragrances, gel deodorants, sweat absorbing fibers, disposable warmers and other household items, shampoos, and sets Toiletries such as gels and moisturizers, water retention materials for agriculture and horticulture, life-promoting agents for cut flowers, floral foam (fixing material for cut flowers), nurseries for raising seedlings, hydroponics, vegetation sheets, seed tape, fluid sowing, Agricultural and horticultural products such as agricultural sheets for preventing dew condensation, freshness-retaining materials for food trays, food packaging materials such as drip-absorbent sheets, cooling materials, and transport materials such as water-absorbent sheets for transporting fresh vegetables, Construction materials for dew prevention, sealing materials for civil engineering and construction, anti-sludge agents for shield method, concrete admixtures, civil engineering and building materials such as gaskets and packing, sealing materials for electronic devices such as optical fibers, waterproof materials for communication cables Used in a wide range of fields, including electrical equipment-related materials such as inkjet recording paper, coagulants for sludge, dewatering of gasoline and oils, water treatment agents such as water removers, printing pastes, water-swellable toys, and artificial snow. Have been.

Further, by utilizing the sustained release properties of the chemicals, it is expected to be used for sustained release fertilizers, sustained release pesticides, sustained release drugs and the like.

Further, application to a humidity control material utilizing its hydrophilicity and an antistatic agent utilizing its charge retention is also expected.

[Prior art relating to water-absorbing resin] Examples of the water-absorbing resin used in such sanitary materials include cross-linked polyacrylic acid partially neutralized products (JP-A-55-84).
No. 304, U.S. Pat. No. 4,625,001), partially hydrolyzed starch-acrylonitrile copolymer (JP-A-46-43995), and starch-acrylic acid graft copolymer (JP-A-51-125468). ), A hydrolyzate of a vinyl acetate-acrylate copolymer (JP-A-52-14689), 2-acrylamide-2
-Methylpropanesulfonic acid / acrylic acid copolymerized cross-linked product (European Patent 0068189), cross-linked product of cationic monomer (U.S. Pat. No. 4,906,717), cross-linked isobutylene-maleic anhydride copolymer (U.S. Pat.
No. 89513) is known.

However, these water-absorbing resins are decomposed at the crosslinked portion and become water-soluble resins. However, since the main chain has no decomposability or only a part thereof is decomposed,
Disposal after use becomes a problem. In particular, polyacrylic acid is
It is reported that up to 7-mers can be decomposed, and oligomers and polymers having 8 or more mers have no biodegradability. (JE Glass and G. Swi
ft Eds. , "Agricultural and
Synthetic polymers: Utili
zation and Biodegradabili
ty ", American Chemical Soc
IETY, Washington, D.C. C. (1990
Year), M. Shimao, H .; Saimoto, Y .; T
aniguchi, N .; Kato, C .; Sakazawa
a: Appl. Environ. Microbio
l. 46, 605-page (1983); Mat
sumura, S.M. Maeda, S.M. Yoshikawa
a, N .; Chikazumi: J. Jpn. Oil C
hem. Soc. (YUKAGAKU), Volume 39, 12
45-page (1990)) That is, these resins are poorly decomposable and exist semipermanently in water and soil, and therefore are very problematic from the viewpoint of environmental conservation in waste treatment. For example, in the case of disposable resins represented by sanitary materials such as disposable diapers and sanitary products, recycling them requires a great deal of cost, and incineration requires a large amount, which imposes a large burden on the global environment. In addition, it is reported that when burying waste containing cross-linked polyacrylic acid resin, it forms a complex with polyvalent ions such as Ca 2+ in soil and forms an insoluble layer (Matsumoto et al.
Polymer, Vol. 42, August, 1993). However, such a layer is said to have low toxicity per se, but since it does not exist at all in nature,
Since the effects on the ecosystem of the long-term accumulation of these resins in the soil are unknown, a careful attitude to their use is desired.

Similarly, in the case of a nonionic resin, a complex is not formed, but it may be accumulated in soil due to its non-decomposability, so that a cautious attitude is desired for its use.

Furthermore, these polymerization resins use monomers that are highly toxic to human skin and the like, and many studies have been made to remove them from products after polymerization. Complete removal can be difficult.
In particular, it is expected that manufacturing on an industrial scale will be more difficult.

[Technical background of water-absorbent resin having biodegradability] On the other hand, biodegradable polymers have recently attracted attention as "earth-friendly materials", and it has been proposed to use this as a water-absorbent resin. ing.

Examples of the biodegradable water-absorbing resin used in such applications include cross-linked polyethylene oxide (JP-A-6-157795), cross-linked polyvinyl alcohol, cross-linked carboxymethyl cellulose (US Japanese Patent No. 4650716), cross-linked alginic acid, cross-linked starch, cross-linked polyamino acid and the like are known.

Among these, crosslinked polyethylene oxide and crosslinked polyvinyl alcohol can be biodegraded only by special bacteria, so that under normal conditions, biodegradability is slow or not decomposed at all. I do.
Further, when the molecular weight is further increased, the decomposability is extremely lowered or the composition becomes non-decomposable.

Crosslinked saccharides such as crosslinked carboxymethylcellulose, crosslinked alginic acid, and crosslinked starch have many strong hydrogen bonds in their molecules, and therefore have strong interactions between molecules and between polymers. The molecular chains could not be widely opened, the absorption capacity was not high, and it was not suitable as a water-absorbing polymer in sanitary articles.

[Technical background of polyamino acid-based water-absorbing resin] On the other hand, a resin obtained by crosslinking a polyamino acid is biodegradable and thus is friendly to the global environment, and is digested by enzymatic action even when absorbed in a living body. It has been shown that it is absorbed, does not show antigenicity in vivo, and that the degradation products have no toxicity, so it is a material that is gentle to humans.

[Demand for Disposable Sanitary Ware] That is, there is a high demand for thinning disposable sanitary ware and disposal of waste, and there has been a strong demand for the emergence of new disposable sanitary materials including the treatment method.

[0038]

One of the objects of the present invention is to solve the above-mentioned problems in the prior art and to provide a degradable superabsorbent composite having biodegradability.

Another object of the present invention is to provide a decomposable superabsorbent composite which is excellent in absorption characteristics and which is thin when used for sanitary materials and the like, and a method for producing the same.

Another object of the present invention is to provide a method for treating the waste of the decomposable superabsorbent composite according to the present invention.

[0041]

Means for Solving the Problems The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, completed the present invention.

That is, the present invention is specified by the following items [1] to [20].

[1] The absorber layer (A layer) is replaced with the support layer (B
A) a decomposable superabsorbent composite laminated on the
The absorbent layer (A layer) is composed of crosslinked polyamino acid particles (a-
1) It is configured to include a composite in which at least a part of the surface is coated with microfibrillar cellulose (a-2), and the support layer (B layer) is a degradable support layer. Degradable super absorbent composite.

[2] The degradable superabsorbent composite according to [1], wherein at least a part of the degradable support layer is a biodegradable support layer.

[3] At least a part of the decomposable support layer is a decomposable support layer in compost.
The degradable superabsorbent composite according to any one of [2].

[4] The decomposable support layer in the compost converts 1 part by weight (dry state) of the degradable superabsorbent complex into 100 parts by weight (wet state) of inoculum (inoculant) of compost (compost). When charged and treated at 58 ° C. for 40 days, the post-treatment dry weight of the degradable superabsorbent composite is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment. The degradable superabsorbent composite according to [3], which has properties.

[5] The degradable superabsorbent composite according to any one of [1] to [4], wherein at least a part of the degradable support layer is a soil degradable support layer.

[6] When the soil-degradable support layer is buried in a decomposable superabsorbent composite of 1 part by weight (in a dry state) 300 mm underground in a field for 6 months, the degradable superabsorbent composite is removed. The degradable superabsorbent composite according to [5], wherein the dry weight of the body after treatment is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment.

[7] The crosslinked polyamino acid particles are
(1) water absorption capacity in which the equilibrium swelling and absorption of physiological saline is 20 to 200 times per unit weight of the dry polymer, (2)
(3) a water absorption capacity in which physiological saline is absorbed for 1 minute and the amount of absorption is 10 to 150 times per unit weight of the dry polymer;
The amount of physiological saline absorbed under a load of 103 kPa (20 g / cm ² ) is 5 to 15 per unit weight of the dry polymer.
Water absorption capacity of 0 times, and (4) a water absorption capacity of 5 to 150 times per unit weight of dry polymer, which can retain water after applying a centrifugal force of 3000 G for 10 minutes to a gel saturated with physiological saline. The decomposable superabsorbent composite according to any one of [1] to [5], which has at least one of the above-mentioned water-absorbing capabilities.

[8] The degradable superabsorbent complex according to any one of [1] to [7], wherein the crosslinked polyamino acid is a crosslinked polyaspartic acid.

[9] The degradable superabsorbent composite according to any one of [1] to [8], wherein the microfibrillar cellulose (a-2) is cellulose or a cellulose derivative.

[10] The high degradability according to any one of [1] to [8], wherein the microfibrillar cellulose (a-2) is obtained by grinding and / or beating pulp. Water-absorbing complex.

[11] The degradable superabsorbent composite according to any one of [1] to [8], wherein the microfibrillar cellulose (a-2) is obtained by microbial metabolism.

[12] The degradable superabsorbent composite according to any one of [1] to [11], wherein the degradable support layer is a layer containing a degradable polymer.

[13] The decomposable support layer is a web,
[1] to [1], which are layers including at least one layer selected from the group consisting of a sheet and a film.
1) The degradable superabsorbent composite according to any one of [1].

[14] The degradable superabsorbent composite according to [13], wherein the web is at least one selected from the group consisting of woven fabric, knitted fabric, nonwoven fabric, and paper.

[15] The decomposable superabsorbent composite is as follows:
(1) Absorption rate when absorbing 20 ml of physiological saline is 0.1 to 50 ml / sec · cm ² , (2) Saturation absorption when absorbing physiological saline is 0 Water absorption capacity of 0.1 to 5 g / cm ² , (3) The absorption amount when absorbing 20 ml of physiological saline while applying a load of 103 kPa (20 g / cm ² ) is 0.
Water absorption capacity of 0.5 to ⁴ g / cm ² , and (4) 111 kPa (1 ton /
m ² ) The amount of return water discharged when a load of
The decomposable superabsorbent composite according to any one of [1] to [14], which has at least one of a water absorbing ability of 7 g / cm ² .

[16] In the decomposable superabsorbent composite obtained by laminating an absorber layer (layer A) on a support layer (layer B), the absorber layer (layer A) is formed of crosslinked polyamino acid particles. (A-1) A composite comprising at least a part of its surface coated with microfibrillar cellulose (a-2), and the support layer (B layer) comprises a degradable polymer. Comprising a cross-linked polyamino acid particle (a-1), a microfibrillar cellulose (a-2), and water and / or a water-miscible organic solvent. The suspension was added to the support layer (B).
A method for producing a decomposable superabsorbent composite, comprising casting into a layer and drying.

[17] The decomposable liquid according to [16], wherein the water-miscible organic solvent is at least one selected from the group consisting of alcohols having 1 to 6 carbon atoms, glycols, ethers, and ketones. A method for producing a superabsorbent composite.

[18] A crosslinked polyamino acid-based resin, wherein at least a part of the surface is coated with microfibrillar cellulose.

[19] A crosslinked polyamino acid resin for a degradable superabsorbent composite, wherein at least a part of the surface is coated with microfibrillar cellulose.

[20] A sanitary article comprising the decomposable superabsorbent composite according to [1].

[0063]

BEST MODE FOR CARRYING OUT THE INVENTION The degradable superabsorbent composite of the present invention is characterized in that the constituent materials are not only degradable because of their biodegradability, but also exhibit functions of water absorption and thinning. In order to promote the decomposition more efficiently, the structure has been devised so that it is easily collapsed.

That is, the degradable superabsorbent composite of the present invention is a composite having both <absorbency>, <disintegration>, <degradability>, and <thin>.

Hereinafter, the present invention will be described in detail.

(1) Structure of Degradable Superabsorbent Composite The present invention relates to a degradable superabsorbent composite, and comprises an absorber layer and a support layer.

The absorbent layer of the decomposable superabsorbent composite of the present invention includes a composite in which at least a part of the surface of the crosslinked polyamino acid particles (a-1) is coated with microfibrillar cellulose (a-2). It consists of. The support layer (B layer) is a decomposable support layer.

The decomposable superabsorbent composite of the present invention may contain, if necessary, inorganic compounds such as salt, colloidal silica, white carbon, ultrafine silica, and titanium oxide powder, and a chelating agent as long as they do not hinder their function. Organic compounds such as oxidizing agents, antioxidants, reducing agents, ultraviolet absorbers, antibacterial agents, bactericides, fungicides, fertilizers, fragrances, deodorants, pigments and the like. The location where these additives are contained may be either the absorber layer or the support layer. If necessary, a material having a deodorizing and deodorizing function may be contained. Further, an antibacterial material for suppressing the propagation of bacteria can be contained.

Further, a method of applying a hydrophobic compound such as a silicone oil agent or paraffin wax to the peripheral portion or a method of applying a hydrophilic compound such as an alkyl phosphate ester in advance to prevent leakage due to bleeding of urine or the like at the peripheral portion. You can prevent it.

Hereinafter, the absorbent layer of the decomposable superabsorbent composite will be described in (2), and the support layer will be described in (3).

(1-1) Degradability of the degradable superabsorbent complex The term “degradability of the degradable superabsorbent complex” in the present invention means that waste after use of the water absorbent composite is waste treatment. Means to decompose.

Specific examples include biodegradability, degradability in compost, and degradability in soil. However, in addition to these, other intrinsic properties can be used for disposal as long as the function of the degradable superabsorbent composite of the present invention is not hindered. For example, high temperature decomposability, oxidative decomposability, reductive decomposability, hydrolysability, alkali decomposability,
Acid decomposability and the like can be mentioned.

Further, the decomposition can be made more efficient by using a process such as stirring, mixing, crushing, shredding, etc. by mechanical means or by performing it as a pre-process.

The term “biodegradable” means that a constituent material is used in a natural environment.
Or, under artificially controlled conditions such as compost, it is decomposed by microorganisms, bacteria, enzymes (bio) such as enzymes,
It means to be a safe small molecule.

The term “in-compost degradability” means that in a compost, biomolecules (organisms) such as microorganisms, fungi, enzymes and the like are decomposed into safe low molecules.

The preferred form is that, for example, 1 part by weight (dry state) of the degradable superabsorbent complex is charged into 100 parts by weight (wet state) of inoculum (inoculant) of compost (compost), and the mixture is heated at 58 ° C. When treated for 40 days, the dry weight of the degradable superabsorbent composite after treatment is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment.

Degradability in soil means that when subjected to a treatment such as being buried in soil or the like, the soil is decomposed biologically by microorganisms, bacteria, enzymes, etc., by bio, and the polymer is low. Refers to the property of becoming a molecule.

The preferred form is, for example, that 1 part by weight of the decomposable superabsorbent complex (in a dry state) is 30
When buried at 0 mm for 6 months, the dry weight of the degradable superabsorbent composite after treatment is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment.

(1-2) Preferred Absorbing Capacity of the Degradable Superabsorbent Complex The degradable superabsorbent complex of the present invention is required to have excellent water absorbing ability as an absorber. In particular, it is preferable that the amount of water absorption under load is large, the water retention capacity under load is large, and the water absorption speed is high.

For example, a sanitary material must be able to sufficiently absorb various body fluids. In the present invention, physiological saline is used as a standard for body fluids, and the water-absorbing ability of the water-absorbing resin is represented.

That is, it is preferable that the decomposable superabsorbent composite of the present invention has at least one of the following water absorbing capacities. (1) Water absorption ability at an absorption rate of 0.1 to 50 ml / sec · cm ² when absorbing 20 ml of physiological saline. (2) When saturated saline is absorbed,
Water absorption capacity of 0.1 to 5 g / cm ² . (3) 20 ml of physiological saline was added to 103 kPa (20 g /
(cm ² ) a water absorption capacity of 0.05 to 4 g / cm ² when absorbed while applying a load. (4) 111 kPa after saturated absorption of physiological saline
Water absorption capacity with a return drainage of 0 to 7 g / cm ² when a load of (1 ton / m ² ) is applied.

Further, it is more preferable to have at least one of the following water absorbing capacities. Those having the following water absorbing ability are more preferred. (1) Water absorption capacity in which the absorption rate when absorbing 20 ml of physiological saline is 1 to 50 ml / sec · cm ² . (2) When saturated saline is absorbed,
Water absorption capacity of 1 to 5 g / cm ² . (3) 20 ml of physiological saline was added to 103 kPa (20 g /
(cm ² ) a water absorption capacity of 0.5 to ⁴ g / cm ² when absorbed while applying a load. (4) 111 kPa after saturated absorption of physiological saline
Water absorption capacity with a return water discharge of 0 to 5 g / cm ² when a load of (1 ton / m ² ) is applied.

There is no upper limit to these performances, and those showing high figures except for (4) are preferable. However, the above numerical ranges are preferred as long as a decomposable superabsorbent composite can be actually produced. .

As a preferred embodiment of the present invention, these values are provided with an upper limit. When the degradable superabsorbent composite of the present invention is used as a sanitary material, the composition is different from that of the degradable superabsorbent composite of the present invention. If they are the same, it does not mean that a degradable superabsorbent composite having a higher performance cannot be used.

(2) Absorbent Layer of Degradable Superabsorbent Composite The absorbent layer (A layer) of the degradable superabsorbent composite of the present invention comprises:
The crosslinked polyamino acid particles (a-1) include a complex in which at least a part of the surface is coated with microfibrillar cellulose (a-2).

In the present invention, crosslinked polyamino acid particles whose surface is at least partially coated with microfibrillar cellulose (hereinafter referred to as a crosslinked polyamino acid complex)
Is described in (2-1), the crosslinked polyamino acid particles are described in (2-2), and the microfibrillar cellulose is described in (2-3).

The degradable superabsorbent composite of the present invention comprises:
Not only a single structure but also a multiple structure can be adopted. In particular, the absorption capacity can be enhanced by adopting a structure in which absorption layers are stacked or by giving a concentration gradient of the water-absorbing resin.

The location of the crosslinked polyamino acid complex is not particularly limited, and may be any of the upper, middle and lower layers of the absorber layer as long as the structure can efficiently absorb body fluid and the like. The state of the distribution is not particularly limited, and it is preferable that the distribution is efficient according to the amount of the target liquid and the injection portion. In order to increase the efficiency, the distribution of the crosslinked polyamino acid particles can be unevenly distributed in advance. In addition, the crosslinked polyamino acid complex can be dispersed and distributed so that its performance can be sufficiently exhibited.

For more efficient diffusion of water, absorbent paper and diffusion paper can be used. The absorption paper and the diffusion paper are also not limited, but usually a paper mainly composed of cellulose is preferred. Further, it may be mixed with pulp in order to make diffusion more efficient.

(2-1) Structure of Crosslinked Polyamino Acid Complex In the present invention, the crosslinked polyamino acid complex is a crosslinked polyamino acid particle whose surface is at least partially coated with microfibrillar cellulose, and has a thin function. It is one of the important factors that can be expressed.

That is, the crosslinked polyamino acid complex is characterized in that it has a core-shell structure in which the crosslinked polyamino acid particles are used as a core portion and microfibrillar cellulose is used as a shell portion.

The details of the crosslinked polyamino acid complex having a core-shell structure will be described below.

[Concept of the Word "Particle"] The term "particle" used in the specification of the present application completely encompasses the concept that these words generally have in polymer chemistry, but is not necessarily equivalent. is not. With respect to the scanning electron microscopic morphology of the “particles” used in the specification of the present application, not only the spherical morphology but also, for example, raspberry-like or gold rice sugar (Konpeitou, Portuguese confeat)
o) An aspect having many projections, an erythrocyte flat aspect, a rugby ball-like spheroid-like aspect, an Escherichia coli-like spindle-like aspect, a thunder squirrel (a famous confectionery of Asakusa)
And the like. The concept of the term “particle” used in the specification of the present application includes, for example, a microsphere having an average particle diameter of about 1 nm to 10 μm, which constitutes a polymer emulsion, a latex, and a polymer suspension, as well as an average particle diameter of 10 μm to 10 μm.
Although particles of about 100 mm are included, in the invention according to the present application, particles having an average particle diameter of about 100 μm to about 25 mm are a general mode.

As described above, the term “particle” used in the specification of the present application is not necessarily equivalent to the concept that these terms generally have in polymer chemistry. For the sake of frequent reference to the essential aspects of heterogeneous systems, they shall be used for convenience.

[Higher Order Particles] In the present invention, the particles may be primary particles or higher order particles. That is,
Even if it is a secondary particle that is an aggregate or aggregate of a plurality of primary particles, even if it is a tertiary particle that is an aggregate or aggregate of a plurality of secondary particles, an aggregate of a plurality of tertiary particles Or, even if it is a quaternary particle which is an aggregate, or even a higher order particle, it is not particularly limited as long as it is suitable.

[Particle Having a Core / Shell Structure] The terms “core”, “shell” and “core / shell” used in the specification of the present application refer to the concept that these terms generally have in polymer chemistry. Includes but is not necessarily equivalent. For example, the “core / shell” particles according to the present invention include embodiments in which the “core” is at least partially enclosed in the “shell”. As described above, the terms “core”, “shell”, and “core / shell” used in the specification of the present application are not necessarily equivalent to the concept that these terms generally have in polymer chemistry. For the sake of frequent reference to the essential aspects of the heterogeneous systems of the polymers according to the invention, they shall be used for convenience.

In the polymer chemistry, generally,
The term “core” is “core, center, n
ucleus) "," core (center) "
And the word "shell" is used equivalently to the word "shell" and the word "shell"
kin, husk), "sheath" and "robe".

Accordingly, the term “core” as used in the specification of the present application refers to “core, cen”.
ter, nucleus) "," core (core, cen)
ter) "and" seed ". Similarly, the term "shell" can be used equivalently to the terms "shell, skin, husk", "sheath" and "robe".

[Structure of Particle] Examples of the core / shell structure include, but are not limited to, the following (1) to (7).

(1) A typical core / shell type embodiment in which the core particle surface is covered with a shell.

(2) An embodiment of a structure in which a shell is partially deposited on the surface of a core particle and is not completely covered.

(3) A so-called salami structure in which a plurality of core particles are sealed by a shell and the cross section is salami sausage.

(4) An embodiment in which the core particles are hollow particles.

(5) An embodiment in which the core particles are porous particles, and the resin constituting the shell does not fill the voids of the porous particles.

(6) An embodiment in which the core particles are porous particles, and at least part of the voids of the porous particles are filled with the resin constituting the shell.

(7) The core particles are porous particles, and the interface between the core phase and the void phase is covered with the resin constituting the shell without filling at least a part of the voids of the porous particles. Mode.

The particles of the present invention may have a single shell phase or a multilayer shell phase as long as the desired function can be substantially exhibited.

The core / shell structure of the particles of the present invention may be either a structure in which the core portion and the shell portion are completely separated, or a state in which the shell portion has penetrated the core portion. It can be designed to express the purpose. Further, a gas phase may be contained between the core and the shell structure.

In the degradable superabsorbent composite according to the present invention, the microfibrillar cellulose is firstly stable to water and secondly, does not impair the absorbability of the crosslinked polyamino acid particles. It acts as a binder and achieves a secondary structure mainly composed of crosslinked polyamino acid particles.

In the present invention, the network structure for binding the crosslinked polyamino acid particles at a predetermined position is constituted by so-called microfibrillar cellulose. This microfibrillar cellulose generally has an average diameter of 2.0 μm to 0.01 μm and an average length of
It is a very thin fibrous material having a thickness of 0.01 μm to 0.1 μm, and has water resistance capable of preventing the structure from being immediately collapsed by swelling when the crosslinked polyamino acid particles absorb water, and , Water permeability and swelling properties of the crosslinked polyamino acid particles.

It should be noted that the microfibrillar cellulose has an extremely strong hydration property which binds to water as a solvation (bound water). When dispersed in water, it hydrates, shows large viscosity, and shows a property of stably maintaining a dispersed state. In the present invention, the term "microfibrillar cellulose" is used as a general term for fibrous materials having strong hydration properties, and in some cases, those having an average diameter exceeding 2.0 μm are also used. It is possible, and a mixture of so-called microfibrillar cellulose and microfibrillar cellulose may be used.

FIG. 1 is an example showing the relationship between the concentration of microfibrillated cellulose (S-MFC) in a dispersion and its viscosity. From FIG. 1, it can be seen that the composition has high viscosity characteristics even at a low concentration. Further, the dispersion liquid of the microfibrillated cellulose shows structural viscosity, shows flow orientation by applying a shear, and lowers the viscosity, but recovers as the shear decreases. Therefore, when the crosslinked polyamino acid particles are added and dispersed in the microfibrillated cellulose dispersion medium, the crosslinked polyamino acid particles are stably incorporated into the network structure of the microfibrillated cellulose in a low-share dispersion state. In addition, it is possible to stably disperse cross-linked polyamino acid particles at a high concentration. In addition, when transported by a pump or the like, the viscosity decreases and transport becomes easier.After the sheet is formed and the dispersion medium is removed and dried, the microfibrillated celluloses self-join to each other to form a plaster. The crosslinked polyamino acid particles can be stably bonded and fixed.

Therefore, when the crosslinked polyamino acid particles are dispersed in the microfibrillated cellulose dispersion medium, a high concentration of the crosslinked polyamino acid particles can be stably dispersed. Self-bonding to form a plaster, forming a network structure, wrapping around the crosslinked polyamino acid particles and mechanically surrounding them, and at the same time, microfibrillated celluloses are bonded by an ionic hydrogen bonding effect, Ensures retention of amino acid particles.

(2-2) Cross-linked polyamino acid particles The water-absorbing resin used in the degradable superabsorbent composite of the present invention is specified as cross-linked polyamino acid particles.

The crosslinked polyamino acid used is not particularly limited, and a partially crosslinked polyamino acid can be used. The basic skeleton of the polyamino acid used in the present invention comprises a polypeptide in which amino acids are dehydrated and condensed. Specific examples of the amino acid component include, for example, 20 kinds of essential amino acids, L-ornithine, a series of α-amino acids, β-alanine, γ-aminobutyric acid, neutral amino acids, acidic amino acids, ω-esters of acidic amino acids, bases Amino acids, N-substituted basic amino acids, amino acids and amino acid derivatives such as aspartic acid-L-phenylalanine dimer (aspartame), and aminosulfonic acids such as L-cysteic acid. The α-amino acid is an optically active form (L
, D-form) or a racemic form.

Further, the polyamino acid may be a copolymer containing another monomer component. Examples of the monomer component of the copolymer include aminocarboxylic acid, aminosulfonic acid, aminophosphonic acid, hydroxycarboxylic acid, mercaptocarboxylic acid, mercaptosulfonic acid, and mercaptophosphonic acid.

Further, polyamines, polyhydric alcohols, polythiols, polycarboxylic acids, polysulfonic acids, polyphosphonic acids, polyhydrazine compounds, polycarbamoyl compounds, polysulfonamide compounds, polyvalent sulfonamide compounds, Phosphonamide compounds, polyepoxy compounds, polyvalent isocyanate compounds, polyvalent isothiocyanate compounds, polyvalent aziridine compounds, polyvalent carbamate compounds, polyvalent carbamic acid compounds, polyvalent oxazoline compounds, polyvalent unsaturated bonds Compounds, polyvalent metals and the like.

In the case of a copolymer, it may be a block copolymer or a random copolymer. Also, it may be a graft.

Among these, polyaspartic acid, polyglutamic acid, and polyaspartic acid, which are homopolymers excellent in biodegradability,
It is preferable to use polylysine as the basic skeleton, and it is preferable to use polyaspartic acid and glutamic acid having high water absorption as the basic skeleton, and particularly preferable is polyaspartic acid suitable for industrial production.

Regarding the side chain structure of the crosslinked polyamino acid used in the degradable superabsorbent complex of the present invention, even if the polyamino acid residue has no substituent, the pendant group derived from the polyamino acid residue may be used. May be included.
In the case of polyaspartic acid, it is a group having a carboxyl group in a structure in which an imide ring is simply opened, but other substituents may be introduced.

For example, there are a group having a carboxyl group in a structure in which an imide ring is simply opened, an amino acid residue such as lysine, a pendant group having a carboxyl group, and a pendant group having a sulfonic acid group. Where the carboxyl group,
In the case of a sulfonic acid group, a salt may be used. Examples of the counter ion of the carboxyl group include alkali metal salts, ammonium salts, and amine salts.

Further, in the case of an acidic polyamino acid, the carboxyl group or side chain group is attached to the amide bond of the polymer main chain. It may be substituted, and in the case of a glutamic acid residue, it may be substituted at the α-position or at the γ-position.

In the case of a copolymer, polyaspartic acid and its copolymer are combined with the amino group of aspartic acid or a copolymer monomer and the carboxyl group at the α-position of aspartic acid. It is a bond, and when it is bonded to the carboxyl group at the β position of aspartic acid, it is a β bond.

In the case of polyaspartic acid, the α-linkage and β-linkage are not particularly limited, and the binding mode is not particularly limited. It may be only an α bond, only a β bond, or a mixture.

The binding portion between the basic skeleton and the side chain of the polyamino acid of the present invention is not particularly limited. In the case of an acidic polyamino acid, it is an amide bond, an ester bond, or a thioester bond. In the case of a carboxyl group, a salt may be formed even in a form in which a hydrogen atom is bonded. As the counter ion of the carboxyl group, alkali metal salts, ammonium salts,
Amine salts and the like.

The polyamino acid used in the present invention is a crosslinked product. The binding portion between the basic skeleton and the crosslinked portion of the present invention is not particularly limited. In the case of an acidic polyamino acid, it is an amide bond, an ester bond, or a thioester bond. These crosslinking portions and side chain portions may be unsubstituted or substituted.

Examples of the substituent include an alkyl group having 1 to 18 carbon atoms which may be branched or unbranched, a cycloalkyl group having 3 to 8 carbon atoms, an aralkyl group and an optionally substituted phenyl group. , A naphthyl group which may or may not be substituted, an alkoxy group which may have 1 to 18 carbon atoms and may be branched, an aralkyloxy group, a phenylthio group, which may have 1 to 18 carbon atoms An alkylthio group, an alkylamino group having 1 to 18 carbon atoms which may or may not be branched, a dialkylamino group having 1 to 18 carbon atoms which may or may not be branched,
Trialkylammonium group having 1 to 18 carbon atoms which may or may not be branched, hydroxyl group, amino group, mercapto group, sulfonyl group, sulfonic acid group, phosphonic acid group and salts thereof, alkoxycarbonyl group, alkyl And a carbonyloxy group.

The basic skeleton, crosslinked portion, and side chain portion of these polyamino acid-based resins are not particularly limited, as long as they can exhibit a sufficient water-absorbing ability as the absorbent resin contained in the absorbent core, regardless of the production method. Any of these resins can be used.

As the crosslinked polyaspartic acid, resins produced by various methods can be used regardless of the production method. For example, a method of partially crosslinking polysuccinimide with a polyvalent amine and hydrolyzing the remaining imide ring with an alkali or the like, mixing aspartic acid, polyaspartic acid and lysine, and crosslinking while polymerizing, Examples thereof include a method of mixing polyaspartic acid and a polyamine and dehydrating and condensing at a high temperature, a method of reacting polyaspartic acid with a polyvalent glycidyl compound, and a method of irradiating an aqueous solution of polyaspartic acid with γ-rays. Any of the resins produced by these methods can be used irrespective of the production method as long as the resin can exhibit a sufficient water absorbing ability as the absorbent resin contained in the absorbent core.

These resins may be used as a mixture of two types. Further, a crosslinked polysaccharide, which is another water-absorbing resin having biodegradability, may be used in combination. If necessary, a water-absorbing resin having no biodegradability may be used together as long as the biodegradability of the sanitary article is not impaired.

The amount of the water-absorbing resin used in the present invention varies greatly depending on the type and amount of the body fluid for the purpose of absorption, and also depends on the intended use. In general, 1.0～500G per sheet 1 m ² is preferable, 10 to 200 g is particularly preferred.

The shape of the crosslinked polyamino acid resin used in the present invention may be irregular crushed, spherical, granular, granular, granulated, scaly, massive, pearl, fine powder, fibrous, rod-shaped. , A film shape, a sheet shape, etc., and a preferable shape can be used depending on the use. Further, it may be a fibrous base material, a porous material, a foam, or a granulated material.
The particle size of these crosslinked polyamino acid-based resins is not particularly limited, but varies depending on the intended use.

For example, in the case of disposable diapers, it is desired that a high absorption rate and no gel blocking occur, so that the average particle diameter is preferably 70 to 1000 μm.
100-500 μm is more preferred.

The crosslinked polyamino acid-based resin used in the sanitary article of the present invention needs to have excellent water absorbing ability. In particular, it is necessary that the water absorption under a non-load is large, the water absorption under a load is large, the water retention under a load is large, and the water absorption speed is high. For example, a sanitary material must be able to absorb various body fluids, but in the present invention,
Using physiological saline as a standard for body fluids, the water-absorbing ability of the water-absorbing resin is shown.

That is, the crosslinked polyamino acid particles used as the water absorbent resin in the sanitary ware of the present invention preferably have the following water absorbing ability. (1) water absorption capacity in which the equilibrium swelling and absorption of physiological saline is 20 to 200 times per unit weight of the dry polymer, (2)
(3) a water absorption capacity in which physiological saline is absorbed for 1 minute and the amount of absorption is 10 to 150 times per unit weight of the dry polymer;
The amount of physiological saline absorbed under a load of 103 kPa (20 g / cm ² ) is 5 to 15 per unit weight of the dry polymer.
Water absorption capacity of 0 times, and (4) a water absorption capacity of 5 to 150 times per unit weight of dry polymer, which can retain water after applying a centrifugal force of 3000 G for 10 minutes to a gel saturated with physiological saline. Has at least one of the above-mentioned water-absorbing abilities.

Further, those having the following water absorbing ability are more preferable. (1) water absorption capacity in which the equilibrium swelling and absorption of physiological saline is 30 to 200 times per unit weight of dry polymer, (2)
(3) a water absorption capacity in which a physiological saline solution is absorbed for 1 minute and the absorption amount is 20 to 150 times per unit weight of the dry polymer;
The amount of physiological saline absorbed under a load of 103 kPa (20 g / cm ² ) is 5 to 15 per unit weight of the dry polymer.
Water absorption capacity of 0 times, and (4) a water absorption capacity of 5 to 150 times per unit weight of dry polymer, which can retain water after applying a centrifugal force of 3000 G for 10 minutes to a gel saturated with physiological saline. Has at least one of the above-mentioned water-absorbing abilities.

Although there is no upper limit to these values, those showing high numbers are preferable, but the above number ranges are preferable as long as the crosslinked polyamino acid-based resin can be actually produced.

As a preferred embodiment of the present invention, these values are provided with upper limits. However, it is not impossible to use a resin having higher performance as the sanitary material of the present invention.

(2-3) Microfibrillar Cellulose The microfibrillar cellulose used in the present invention can be obtained by subjecting cellulose or a cellulose derivative to microfibrillation treatment. For example, wood pulp can be obtained by grinding and highly beating through a process as shown in FIG. The microfibrillated cellulose is called MFC (microfibrillated cellulose), and the one with more advanced microfibrillation is called S-MFC (super microfibrillated cellulose).

Microfibrillated cellulose can also be obtained by metabolism of microorganisms. Generally, Acetobacter Xylin (Acetobacter Xylin) is used.
um), etc., by stirring and culturing a so-called acetic acid bacterium in a medium containing an appropriate carbon source to produce crude microfibrillated cellulose, and then purifying it. This microfibrillated cellulose is called BC (bacterial cellulose).

Further, a so-called fibril-like substance obtained by coagulating a spin-forming cellulose ammonia solution of cellulose, an amine oxide solution, an aqueous solution of cellulose xanthate, or an acetone solution of diacetyl cellulose under shear stress is further disintegrated. It is also possible to use a microfibril-like substance obtained by the above method.

Preferably, the microfibrillated cellulose (a-2) is cellulose or a cellulose derivative,
More preferably, the pulp is obtained by grinding and / or beating, or obtained by microbial metabolism.

The details of these microfibrillated celluloses are described in JP-B-48-6641, JP-B-50-38720, etc., and are available under the trade names "Cercream" (manufactured by Asahi Kasei Corporation), It is commercially available under the trade name “Selish” (manufactured by Daicel Chemical Industries, Ltd.), etc. Particularly, those suitable for the present invention have a water retention value of 250.
% Of S-MFC and BC.

(3) Support layer of the degradable superabsorbent composite The support layer of the degradable superabsorbent composite of the present invention is a degradable support layer, and the degradable superabsorbent composite is a sheet. Has a function as a support to be constructed as a structure of
Further, the support layer itself may have a function of promoting diffusion of the liquid to be absorbed. That is, the support layer acts as a physical support and a medium for diffusion.

The support layer of the decomposable superabsorbent composite of the present invention is not particularly limited as long as it has a decomposable material. preferable.

Hereinafter, the constituent material of the support layer of the degradable superabsorbent composite will be described in (3-1), and the structure of the support layer of the degradable superabsorbent composite will be described in (3-2).

(3-1) Constituent Material of Support Layer of Degradable Superabsorbent Composite The degradable polymer in the present invention is a polymer material having biodegradability. Such materials are divided into non-fusible and fusible materials.

Specific examples of the non-melting material include pulp, cotton, wool, regenerated cellulose fiber, solvent-spun cellulose fiber and the like. Specific examples of pulp include, for example, virgin pulp from wood and pulp recovered from waste paper.

As specific examples of the fusible material, for example,
Aliphatic polyesters or aliphatic polyesteramides are mentioned. Specific examples of the aliphatic polyester include, for example, polyglycoside, poly (α-hydroxycarboxylic acid) such as polylactic acid, poly-ε-caprolactone, poly-β-propiolactone, poly-3-hydroxypropionate. , Poly-3-hydroxybutyrate, poly-3
-Hydroxycaprolate, poly-3-hydroxyheptanoate, poly-3-hydroxyoctanoate, and poly-3-hydroxyvalerate, poly-4
Polyhydroxyalkanoates such as copolymers with hydroxybutyrate, polyethylene oxalate, polyethylene succinate, polybutylene succinate,
Polybutylene adipate Polybutylene sebacate, polyhexamethylene sebacate, polyneopentyl oxalate and condensates of dihydric alcohol and divalent carboxylic acid such as copolymers thereof, and furthermore, dihydric isocyanate compounds Those having a chain-extended urethane bond are exemplified. Specific examples of the aliphatic polyesteramide include, for example, lactone and lactam copolymers such as a copolymer of ε-caprolactone and ε-caprolactam.

(3-2) Structure of Support Layer of Degradable Superabsorbent Composite The support layer of the degradable superabsorbent composite of the present invention comprises
This is a structure using the material described in 1).

As the structure of the support layer, for example, non-sized paper, a water-permeable porous sheet such as a nonwoven fabric, a cellophane, a vinylon film, a PVA film, and a thermoplastic film were foamed so as to have fine communication holes at the time of film production. Addition of inorganic or high melting point nucleating agent and drawing to form fine communicating holes, mixed paper of biodegradable plastic and pulp, composite of paper and non-woven fabric, size paper and non-woven fabric Viscose formed cellulose membrane, cellulose membrane formed fine pores, biodegradable plastic film or porous film, metal foil, part or all of the biodegradable plastic Non-woven fabrics made by impregnating or mixing biodegradable plastic into non-woven fabric, rayon, pulp, etc. Nonwoven, and the like made of a disintegrable plastic.

Among these, those in which the decomposable support layer is composed of a web, a sheet and a film are preferred. Among the webs, woven fabric, knitted fabric, non-woven fabric, paper and the like are preferable. Further, in consideration of industrial production, nonwoven fabric is particularly preferred. (3-
The details will be described in 3).

(3-3) Nonwoven fabric forming support of decomposable superabsorbent composite Nonwoven fabric according to ASTM is "a web in which fibers are joined by a joining material or a cloth-like material having a mat-like structure". According to the Japan Non-woven Fabrics Association, "Dry webs are made by combining and adhering constituent fibers by mechanical, thermal, or a combination of them. Weaving, knitting, crimping, etc. Although it is defined as a cloth-like material that does not depend on the method of the present invention, in the present invention, a staple of natural or artificial fiber, which is a broader meaning,
Alternatively, a continuous filament is defined as an adhesive, a molten fiber, or a cloth-like substance joined by a mechanical method.

The production method is not particularly limited, and various methods can be used. For example, without using water as a medium, a dry method in which a fiber sheet is formed by a card for spinning or a garnet or other device, a raw fiber is dispersed in a liquid containing water or a binder, and a paper machine is used. And a direct method of forming a fiber and simultaneously forming a nonwoven fabric.

[0155] The dry method comprises the steps of loosening or blending the raw material fibers in a cotton opener or blending them with a cotton blender and forming them into a thin sheet (web), and joining the obtained webs.

The web is made by crossing and arranging parallel webs made of cards or garnets in a crossed manner. The opened fibers are blown off by an air stream and uniformly dispersed on a perforated cylinder (condenser). Accumulation (a
ir-lay). A nonwoven fabric may be formed using short fibers such as sulfite pulp or cotton linter without using an adhesive.

[0157] Web joining methods include an adhesive method and a mechanical joining method. The method using an adhesive uses a synthetic resin solution or emulsion, a dipping method, a roll method,
There are a foaming method, a printing method, a spraying method, a method using synthetic resin powder, and a method using fibers as a binder. The mechanical joining method includes a needle punch method and a stitch method.

In the wet method, fine irregular branch-like binders (fibrids) made of a thermoplastic resin are mixed with ordinary fibers in a wet pulp-like state to form a slurry, which is then converted to a sheet by a paper machine. And a method in which the binder is melted by heating to melt the binders, and a method in which multicellular self-bonding viscose rayon or the like is mixed with various kinds of fibers to form a slurry in water, and a wet mat is formed and dried. Also, fibrillated fibers can be used in a similar manner. The spunbond method of entanglement by a high-pressure water flow is also classified as a wet method.

As the direct method, there are a spray fiber method and a spun bond method.

In the spray fiber method, a raw polymer material is melted or thermally melted and jetted from a spinning nozzle, and is blown off by an air stream jetted from around the nozzle to form cut fibers, and the screen of a conveyor is used. When forming a random mat composed of extremely fine fibers accumulated on the top, a static electricity is applied to the spinning cylinder to uniformly disperse the spinning cylinder.

In the spunbonding method, a filament melt-spun from a spinning nozzle is guided into a suction jet, and is drawn downward as it is drawn by a compressed air flow. The filament is charged by static electricity applied to the suction jet. This is a method in which the fibers are uniformly opened and a uniform random web is formed in a lower receiver.

The raw fibers used as the material for the nonwoven fabric used in the sanitary ware of the present invention are preferably biodegradable polymer materials. For example, for example, (3-
It is composed of the meltable polymer material mentioned in 1), an organic solvent such as glycerin, and an antioxidant. Further, specific examples include polycaprolactone / polybutylene succinate /
Hot melt adhesives consisting of glycerin / antioxidants can be mentioned.

(4) Method for Producing Degradable Superabsorbent Composite The method for producing the degradable superabsorbent composite of the present invention is not particularly limited, but a preferred method is exemplified.

As the method, (4-1) crosslinked polyamino acid particles, microfibrillar cellulose, and
A suspension comprising water and / or a water-miscible organic solvent,
A method of casting on a support layer and drying, and (4-2) dispersing crosslinked polyamino acid particles on the support layer, and containing microfibrillar cellulose and water and / or a water-miscible organic solvent thereon And drying the suspension. (4-1) A method of casting a suspension containing crosslinked polyamino acid particles, microfibrillar cellulose, and water and / or a water-miscible organic solvent on a support layer, and drying the suspension. A dispersion medium comprising a mixed solvent of a water-miscible organic solvent and water, capable of suppressing swelling of polyamino acid particles and capable of hydrating and dispersing hydratable microfibrillar cellulose obtained from cellulose or a cellulose derivative. In the, the crosslinked polyamino acid particles and the microfibrillar cellulose are dispersed, and the crosslinked polyamino acid particles and the microfibrillar cellulose are separated from the mixed solvent from the obtained dispersion,
Then, the solvent is removed and then dried.

In the present invention, in producing the crosslinked polyamino acid complex as described above, the dispersion behavior of the crosslinked polyamino acid particles in the dispersion medium of the microfibrillated cellulose and the microfibrillated cellulose after desolvation are performed. Uses the behavior cleverly. That is, the crosslinked polyamino acid complex of the present invention is characterized in that the microfibrillated cellulose is stably hydrated and dispersed, in a dispersion medium comprising a mixed solvent of a water-miscible organic solvent and water, the crosslinked polyamino acid particles and the Disperse microfibrillated cellulose,
The crosslinked polyamino acid particles and the microfibiliform cellulose can be separated from the mixed solvent from the obtained dispersion, desolvated, and then dried. As a result, a typical decomposable superabsorbent composite of pulp press containing 90% or more of crosslinked polyamino acid particles can be obtained.

First, in order to prepare a dispersion of microfibrillated cellulose, an aqueous dispersion of microfibrillated cellulose having a relatively high concentration is prepared and used as a mother liquor. As the concentration of the mother liquor, the higher the concentration, the more compact the production apparatus, but the higher the viscosity, the more difficult it is to handle, so that it is 10% or less, preferably 5% to 1%.
Is used. This microfibrillated cellulose mother liquor is added to a mixed solvent of an organic solvent and water to prepare a microfibrillated cellulose dispersion having a predetermined concentration of the microfibrillated cellulose and a viscosity associated therewith. As a means for mixing and adding crosslinked polyamino acid particles,
A method of dispersing crosslinked polyamino acid particles in the above-mentioned microfibrillated cellulose dispersion liquid is generally used.

The organic solvent used in the present invention can be used in principle as long as it is compatible with water and does not greatly swell the crosslinked polyamino acid particles. Examples thereof include methyl alcohol, ethyl alcohol, isopropyl alcohol, and the like. Ethylene glycol, propylene glycol, dioxane, acetone, tetrahydrofuran, glycerin,
Neopentyl glycol, pentaerythritol, dimethyl sulfoxide and the like.

Among them, those which are easy to volatilize during drying and have high safety are preferable. For example, C 1-6
Preferred are alcohols, glycols, ethers and ketones.

By dispersing the microfibrillated cellulose and the crosslinked polyamino acid particles in the mixed solvent comprising the organic solvent and water, a network structure of the microfibrillated cellulose is formed, and the crosslinked polyamino acid particles are incorporated. When the dispersion state is secured and the mixed solvent is subsequently removed, the three-dimensional structure is formed by the physical entangled structure of the microfibrillated cellulose and the formation of stable hydrogen bonds between the microfibrillated cellulose. It is presumed that a simple structure is formed.

The mixing ratio between the organic solvent and water is set within a range that enables the formation of a network structure of the microfibrillated cellulose and suppresses water absorption of the crosslinked polyamino acid particles as much as possible. When using methyl alcohol, ethyl alcohol and acetone as organic solvents,
The results of measuring the relationship between the concentration of each organic solvent and the absorption ratio of the crosslinked polyamino acid particles are shown in the graph of FIG. From FIG.
In the case of ethyl alcohol and acetone, it can be seen that the absorption ratio of the crosslinked polyamino acid particles sharply increases when the concentration becomes 50% or less. In the case of methyl alcohol, the absorption ratio of the crosslinked polyamino acid particles sharply increases at 60% or less. On the other hand, in order to hydrate and stably disperse the microfibrillated cellulose, it is advantageous that the content of water in the mixed solvent is large. Therefore, the mixing ratio of the organic solvent / water is suitably in the range of 90/10 to 40/60. This ratio slightly varies depending on the organic solvent used and the properties of the crosslinked polyamino acid particles used. In some cases, a three-component solvent system may be employed to widen the stability region. For example, a three-solvent system of PGA / ethanol / water.

In the co-dispersed state of the crosslinked polyamino acid particles and the microfibiliform cellulose in the mixed solvent, the respective dispersion concentrations of the crosslinked polyamino acid particles and the microfibiliform cellulose, the crosslinked polyamino acid particles and the microfibiliyl cellulose, The concentration ratio of dendritic cellulose will be described in more detail. The concentration of the cross-linked polyamino acid particles varies depending on the method of transporting the system, but is selected from the range of 60% or less, preferably 50% to 5%, from the viewpoint of ease of handling. The microfibrillated cellulose concentration is affected by the bonding strength and dispersion stability of the crosslinked polyamino acid particles. To maintain good dispersion stability, 0.2% or more is required, and preferably 0.3% to 1.0%.

The mixed solvent containing the microfibrillated cellulose at such a concentration shows good dispersion stability as described above, and hardly causes phase separation even after being left for a long time. According to the results of the experiment, the dispersion stability became better as the concentration of the microfibrillated cellulose became higher. At 0.3%, phase separation did not occur until 1 hour, and at 0.5%, 65 hours later. No phase separation was observed. This good dispersion stability not only facilitates the operation at the time of application, but also demonstrates that the microfibiliform cellulose can uniformly surround the crosslinked polyamino acid particles and stably disperse it. Is presumed to form the basis of excellent water absorption of the degradable superabsorbent composite of the present invention.

The ratio of microfibrillated cellulose to crosslinked polyamino acid particles (MFC / crosslinked polyamino acid particles × 100 (%)) increases as the value increases, but it becomes paper-like and hard. , 20% or less. If it is less than 0.3%, it is difficult to obtain a sufficient bonding force. The evaluation of this bonding force can be performed with the aid of the cellophane tape method used for measuring the surface strength,
A more preferable range from the result is 5% to 0.5%. (4-2) spraying the crosslinked polyamino acid particles on the support layer,
Method for Casting and Drying a Suspension Containing Microfibrillar Cellulose and Water and / or a Water-miscible Organic Solvent In the present production method, the microfibrillar cellulose and water and / or water A suspension comprising a miscible organic solvent is referred to as a coated binder because it dries and removes the solvent to coat and bind the crosslinked polyamino acid particles.

Examples of the method for spraying the crosslinked polyamino acid particles include a method using a slide with a vibrator, a screw type feeder, a grid roll, or the like, or a method using static electricity such as electrostatic coating.

A part of the crosslinked polyamino acid particles spread on the sheet-like support is fixed by being entangled in the mesh of the sheet-like support cloth, but most of the crosslinked polyamino acid particles are not fixed. Even in this state, there is no problem because it is finally fixed by the covering binder. However, it is more desirable to fix the crosslinked polyamino acid particles during the production, because loss due to spilling of the crosslinked polyamino acid particles and deviation of the crosslinked polyamino acid particles due to displacement are reduced.

Specifically, as a method of temporarily fixing the crosslinked polyamino acid particles, for example, a fixing method having a property of fixing the movement of the resin powder between the sheet-like support of the first layer and the superabsorbent resin powder is used. This is achieved by applying an agent.

That is, for example, a small amount of water enough for the crosslinked polyamino acid particles to adhere to the sheet-like support is temporarily or partially applied to the sheet-like support. Can be fixed.

The fixing agent used in the present invention is, instead of water,
Alcohols such as ethylene glycol, propylene and glycol which do not swell the crosslinked polyamino acid particles, or an aqueous solution thereof can also be used. Further, a dispersion of a coated binder of microfibrillar cellulose can be used to increase the fixing strength of the crosslinked polyamino acid particles.

Adhesive aqueous solutions such as carboxymethylcellulose, carrageenan, hydroxyalkylcellulose, sodium alginate, polyvinylpyrrolidone, polyethylene oxide and sodium polyacrylate;
Alternatively, by applying an emulsion adhesive such as a polyvinyl acetate emulsion, the crosslinked polyamino acid particles can be firmly fixed to the sheet-like support. However, since the above adhesive has a risk of impairing water permeability, its use amount is naturally limited, and is 2.0% in terms of adhesive solid content.
g / m ² or less. Alternatively, if microfibrillar cellulose is mixed with the adhesive aqueous solution and used, the fixing strength of the crosslinked polyamino acid particles can be further increased without impairing the water permeability.

The coated binder has water permeability and is used for the purpose of firmly fixing the dispersed crosslinked polyamino acid particles so that they do not move or fall off even if the sheet-like support is bent or stretched. Used.

That is, the coated binder containing microfibrillar cellulose as a main component used in the present production method binds with extremely strong hydrogen bonds in addition to physical entanglement of the microfibrillated cellulose, and thus has a micro A fibril-like cellulose network structure is formed. That is,
Due to this network structure, almost the entire surface of each crosslinked polyamino acid particle is not coated with the microfibrillated cellulose, but as shown in FIG. By coating so as to cover the microfibrillated cellulose layer, the crosslinked polyamino acid particles can be fixed to the sheet-like support. In addition, when dried, the extremely thin network structure is weakened and has extremely good water permeability without inhibiting swelling of the crosslinked polyamino acid particles.

Examples of the method for forming the coating tie layer include a method of spraying a dispersion of the microfibrillar cellulose on the upper surface of the crosslinked polyamino acid particles or a method of curtain coating. At the same time, using a decompression device, when the dispersion is sprayed or painted while suctioning a sheet-like support surface different from the surface to which the crosslinked polyamino acid particles are dispersed, the dispersion does not stop on the upper surface of the crosslinked polyamino acid particles and between the crosslinked polyamino acid particles and It is also dispersed on the sheet-like support, and the fixation of the crosslinked polyamino acid particles on the sheet-like support becomes strong.

After coating the above coated binder,
By removing the solvent used for the temporary fixation, the water or the organic solvent used as the dispersion liquid of the microfibrillated cellulose by a method such as drying, the composite contains 70% by weight or more of the crosslinked polyamino acid particles. A typical pulp decomposable superabsorbent composite can be obtained. (Crosslinked polyamino acid particles) / (Crosslinked polyamino acid particles + coated binder)
Is 90% by weight or more. In particular, when water is used, although the amount of water is small, it is necessary to remove water as quickly as possible since the crosslinked polyamino acid particles swell by absorbing water.
It is desirable to dry within minutes.

After coating the coated binder,
There is no problem if the sheet-like support is laminated on the surface of the coating bonding layer and dried.

When the coated binder was sprayed near the position where the crosslinked polyamino acid particles were sprayed, the layer formation between the crosslinked polyamino acid particles and the coated binder could not be clearly distinguished, and each had a concentration gradient. A layer is formed, but such a layer may be formed without any problem.

The decomposable superabsorbent composite of the present invention may be a crosslinked polyamino acid particle having a coating and binding layer formed on the entire surface, or a striped or island pattern-formed shape. The shape may be selected according to the purpose of use and the form of use. In particular, according to the method of the present invention, JP-A-11-034200 (Japanese Patent Application No. 9-19)
No. 2159), it is extremely easy to form a pattern.

The degradable superabsorbent composite in which the crosslinked polyamino acid particles are formed in a stripe shape is, for example, as shown in FIG. 5, provided on the upper surface of a moving sheet-like support for temporary fixing of the crosslinked polyamino acid particles. After applying the solution in stripes,
It can be manufactured by spraying a large number of spraying ports from a crosslinked polyamino acid particle spraying apparatus arranged at right angles to the moving direction of the sheet. Here, the decomposable superabsorbent composite is obtained by applying a solution for temporary fixing of crosslinked polyamino acid particles in an island shape, and then intermittently applying the crosslinked polyamino acid particles by the above-described spraying device, and then intermittently applying the coating binder. It can be manufactured by doing. (4-3) Other Additive Components Whether or not other components can be added to the crosslinked polyamino acid particles and the microfibrillated cellulose coexisting dispersion system will be described. In the present invention, one of the important points is how to handle the crosslinked polyamino acid particles at a high concentration. Considering the binding efficiency between microfibrillated cellulose and crosslinked polyamino acid particles, a two-component system of crosslinked polyamino acid particles and microfibrillated cellulose is desirable, but as a thickener to further increase the viscosity stability of the system. In some cases, addition of CMC or the like, or addition of polyethylene glycol or glycerin as a plasticizer to prevent curing due to overdrying may be required. It is also possible to add a wood pulp slurry or a synthetic fiber dispersion slurry to the above-mentioned dispersion system, but these additions hinder the stability of the dispersion, and the microfibrillated cellulose and the crosslinked polyamino acid particles are dispersed. Coupling efficiency will also be reduced and should be kept to a minimum. (4-
4) More Specific Production Method Next, a method for forming a composite from a dispersion in which microfibrillated cellulose and crosslinked polyamino acid particles are dispersed in a mixed solvent will be described with reference to the drawings. As a method of forming a composite from the so-called slurry-like dispersion, for example, as shown in the process of FIG. 7, a block-like material obtained by separating a solvent from a slurry is dried, and then pulverized into particles. Then, a spherical particle as shown in FIG. 8A or a flake-like particle as shown in FIG. 8B in which the surface of the crosslinked polyamino acid particles is coated with microfibrillated cellulose is obtained. If, for example, the slurry is poured into a mold made of a net and solid-liquid separated and then dried, pellets are formed according to the mold used,
A shape-shaped composite having a three-dimensional structure such as a rod, a cylinder, and a corrugated plate can be obtained. If a thin film is continuously formed and dried, a sheet-shaped degradable superabsorbent composite can be obtained. Since the composite thus obtained becomes flexible due to moisture content, a sheet-like degradable superabsorbent composite is formed into a mat shape together with the fibers by, for example, an airlaid method, It is also possible to reshape it into a sheet by giving it moisture and pressing and drying.

Hereinafter, a method of directly forming a sheet from a dispersion liquid, which is particularly versatile, will be described in detail. The network structure of the microfibrillated cellulose as described above makes it possible to form a very thin layer while keeping the state in which the crosslinked polyamino acid particles are stably and firmly held. That is, a dispersion liquid in which microfibrillated cellulose and crosslinked polyamino acid particles are dispersed in a dispersion medium is cast on an appropriate plane, and a sheet-like degradable material composed of only microfibrillated cellulose and crosslinked polyamino acid particles is formed. A superabsorbent composite can be formed. FIG. 9A shows the decomposable superabsorbent composite layer 10 of this embodiment. In FIG. 9A, reference numeral 11 denotes microfibrillated cellulose, and 12 denotes crosslinked polyamino acid particles. In a preferred example, each crosslinked polyamino acid particle is completely encapsulated by fine microfibrillated cellulose, as shown in FIG. 9 (b), sketched from a 70 × photomicrograph. It is incorporated in the network structure of the microfibrillated cellulose entangled with the amino acid particles by the microfibrillated cellulose.

When the dispersion is cast on a suitable sheet-like support, after the dispersion is dried, the degradable superabsorbent composite comprising the sheet-like support and the degradable superabsorbent composite layer is formed. Is obtained. In particular, when a porous non-woven fabric is used as the sheet-like support, a part of the dispersion liquid enters the space between the fibers of the non-woven fabric according to the degree of porosity, and after the dispersion liquid is dried, FIG. As shown in FIG. 10 (b) sketched from a micrograph, a composite having a structure in which the sheet-like support 13 and the degradable superabsorbent composite layer 10 are entangled at the joint surface between them. The preferred porosity of this nonwoven fabric is
If indicated by the apparent specific gravity of 0.2 g / cm ³ or less, more preferably from 0.01 to 0.1 g / cm ^3. In addition, as a constituent material of the nonwoven fabric in this case, a hydrophilic material such as cotton, rayon, wood pulp,
Alternatively, it is desirable to use a material obtained by subjecting synthetic fibers such as polyethylene, polypropylene and polyester to hydrophilic treatment. In particular, microfibrillated cellulose is S-MF
In the case of C and BC, in addition to physical confounding, hydrogen bonding is extremely strong.
When dried, they bond more strongly and stably. It also shows very good permeability when wet. As the shape of the non-woven fabric used as the support, in addition to non-woven fabrics such as porous card dry type and spun bond, sheet-like materials such as surface brushed non-woven fabric, weakly carded card web, or opened tow can be used. is there.

As shown in FIG. 11, in the structure shown in FIG. 10, another sheet material is joined so as to be in contact with the sheet-like support 13 so as to be in contact with the decomposable superabsorbent composite layer 10. You can also. As another sheet material,
If a liquid-impermeable sheet material is used, the decomposable superabsorbent composite of FIG. 11 alone can have the function of an absorbent product consisting of a top sheet, an absorbent and a back sheet.

Further, in the structure shown in FIG. 10, the decomposable superabsorbent composite layer can be provided over the entire surface of the sheet-like support, but can also be provided partially in a desired pattern. For example, as shown in FIG. 12, only one surface of the sheet-like support 13 is provided with a plurality of degradable superabsorbent composite layers 10 at predetermined intervals in the form of a strip having a given width, and adjacent to each other. A zigzag cross section can be formed between the degradable superabsorbent composite layers 10 by folding in a mountain fold and a valley fold. The composite having such a configuration exhibits a larger absorbing capacity because the volume of the degradable superabsorbent composite layer 10 existing per unit area is larger than that of a flat composite. Alternatively, as shown in FIG. 13, when the zigzag mountain is greatly inclined in one direction, the volume of the degradable superabsorbent composite layer 10 existing per unit area can be further increased. Further, as shown in FIG. 14, ridges inclined in opposite directions may be provided on both sides of the flat central portion.

Further, such a zigzag structure also provides a free and sufficient space for the crosslinked polyamino acid particles to easily swell by absorption when used as an absorbent product.

FIG. 15 is a perspective view showing an example of the decomposable superabsorbent composite constructed according to the present invention. In this degradable superabsorbent composite, a degradable superabsorbent composite layer 10 is arranged on one surface of a sheet-like support 13 made of an elastic body, in a band shape extending in parallel with each other at a predetermined interval, A corrugated liquid-permeable nonwoven fabric 14 is disposed thereon, and the liquid-permeable nonwoven fabric 14 has a structure in which the liquid-permeable nonwoven fabric 14 and the sheet-like support 13 are joined at a joint 15 at each valley. Accordingly, each decomposable superabsorbent composite layer 10 is accommodated in a channel 16 formed between the sheet-like support 13 and the liquid-permeable nonwoven fabric 14.

The degradable superabsorbent composite having such a configuration is large in a direction perpendicular to the length direction of the degradable superabsorbent composite layer 10 in an absorbent product such as a sanitary napkin or a diaper. It can be advantageously used as a composite having elasticity and excellent water absorption.
In this case, the liquid-impermeable nonwoven fabric 14 is used as the side in contact with the body, and the liquid is first absorbed and diffused by the liquid-impermeable nonwoven fabric 14, and then the decomposable superabsorbent composite layer 1
Absorbed to zero. As the water absorption increases, the volume of the decomposable superabsorbent composite layer 10 expands, which is located in a channel 16 formed between the sheet-like support 13 and the liquid impermeable nonwoven fabric 14. , Free expansion is allowed.

FIG. 16 shows an application example of the degradable superabsorbent composite of the present invention. In FIG. 16, the liquid-impermeable sheet indicated by reference numeral 21 is liquid-impermeable and has a suitable flexibility, and the superabsorbent composite sheet material 22 is superimposed on the liquid-impermeable sheet 21. I have. These two parts are connected to each other at a number of connecting parts 23 extending in a linear or band shape parallel to each other and arranged at a predetermined interval. The connecting portion 23 is formed by heat-sealing the liquid impermeable sheet 21 and the highly water-absorbing composite sheet material 22 with a predetermined width by ordinary means, for example, heat sealing, high-frequency bonding, or the like.

The length of the highly water-absorbent composite sheet material 22 between the two connecting portions 23 adjacent to each other is longer than the length of the liquid impermeable sheet 21. Therefore, between the connecting portions 23, 23, A channel 24 is formed between the superabsorbent composite sheet material 22 and the liquid impermeable sheet 21 due to the slackness of the superabsorbent composite sheet material 22.

The superabsorbent composite sheet material 22 is made of polypropylene (PP) or polyethylene (PE).
Such a structure as shown in FIG. 10 obtained by supporting a decomposable superabsorbent composite layer 10 on one surface of a sheet-like support 13 such as a polyolefin spun bond or a dry nonwoven fabric. Degradable superabsorbent composite layer 10
Is placed on the side facing the liquid impermeable sheet 21.

[0198] The sheet-like product having such a configuration is as follows.
Even when a large amount of liquid is absorbed, it is extremely excellent in self-retaining property for maintaining a sheet-like shape stably.

Next, an apparatus suitable for producing the degradable superabsorbent composite of the present invention will be described with reference to the drawings.

In FIG. 17, reference numeral 31 denotes a tank for storing ion-exchanged water, 32 denotes a tank for storing microfibrillated cellulose mother liquor, 33 denotes a tank for storing acetone, and 34 denotes a tank for storing SAP.
The microfibrillated cellulose aqueous dispersion mother liquor taken out of the tank 32 is introduced into a mixer 35 provided with a stirrer, and is diluted in the mixer 35 with the water taken out of the tank 31, and then, by the action of a pump. Then, it is introduced into a mixer 36 provided with the next stirrer. This mixer 36 has a tank 3
Acetone taken out of 3 is introduced, and this mixture is, by the action of a pump, mixed with the next mixer 3 equipped with a stirrer.
7 is introduced. Granular SAP is introduced into the mixer 37 from the tank 34, where a mixed dispersion of microfibrillated cellulose, an organic solvent, water and SAP is formed.

On the other hand, after a suitable sheet-like support 13 such as a non-woven fabric is unwound from a roll 38,
It is led to 0. The forming section 40 includes a belt conveyor 41.
And the nozzle 4 located on the belt of this belt conveyor
The mixed solvent is supplied to the nozzle 42 from the mixer 37 by the action of a pump.
While the sheet-like support 13 is guided by the belt conveyor 41 and travels at a predetermined speed, the mixed dispersion from the nozzle 42 is applied to the surface thereof. The nozzle 42 has an appropriate shape according to the pattern of the decomposable superabsorbent composite layer to be provided on the sheet-like support 13.

The forming section 40 is further provided with a roll press 43 comprising a pair of rollers, and by pressing the sheet-like support 13 coated with the mixed solvent,
The solvent contained in the mixed solvent is squeezed, and the separated solvent is returned to the mixer 36 by the action of a pump.

After leaving the forming section 40, the sheet-like support 13 is sent to the next drying section 50. Hot air is supplied to the drying unit 50 and a pair of heating rolls 51 and 52 are provided.
The sheet-like support 13 and the mixed solvent applied thereto are dried while being conveyed along the peripheral surfaces of the heating rolls 51 and 52.

After leaving the drying section 50, the product in which the decomposable superabsorbent composite layer is provided on the sheet-like support 13 by a compression section 60 comprising a pair of press rolls 61 and 62 is formed. can get. FIG. 18 shows the steps shown in FIG.
This is a combination of the steps of producing microfibrillar cellulose from acetyl cellulose. In this step, the acetate dope and the tank 3
The coagulation liquid is stored in 2a, and the acetone is stored in tank 33a. The acetate dope and coagulation liquid taken out of tanks 31a and 32a are sent to a suitable fibrillator 39 such as an aspirator, where fibrillation is performed. . The microfibrillar cellulose is mixed in a mixer 35a.
And then slurried into finer microfibrillated cellulose, mixed with acetone from tank 33a in mixer 36a and then mixed with SAP in the next tank (not shown). . The following steps
This is the same as the step shown in FIG.

Referring again to FIG. 17, another example of an apparatus for applying the mixed dispersion to the sheet-like support 13 in the forming section 40 is shown in FIG. In FIG. 19, reference numeral 44 is
A tank with an open top for containing the mixed dispersion is shown.
Inside, with a part of the peripheral surface immersed in the mixed dispersion,
An immersion roll 45 rotatable about a horizontal axis is provided. Further, a pair of rolls 46 and 47 are provided rotatably about axes parallel to the immersion roll 45, respectively. One of the rolls 46 is pressed against the peripheral surface of the immersion roll 45, and has a number of ring-shaped grooves 46a on the peripheral surface, as shown in FIG. 20, for example, and the other has a flat surface. The sheet-like support 13 to which the mixed dispersion is to be applied passes through the nip between the roll and the roll 47.

The mixed dispersion contained in the tank 44 is
It adheres with its own viscosity to the peripheral surface of the immersion roll 45 moving in it, and is then transferred to the sheet-like support 13 via the grooved roll 46. Therefore, the sheet-like support 13
As shown in FIG. 21, a mixed dispersion layer 48 is formed in a number of bands parallel to each other, as shown in FIG. The pattern of the concavities and convexities formed on the roll 46 can be set arbitrarily, and the mixed dispersion can be applied to the sheet-like support 13 in a pattern corresponding to this pattern.

(5) Method of Treating Degradable Super Absorbent Complex Waste One of the features of the present invention is to propose a method of treating the degradable super absorbent complex waste produced by the present invention. is there. The feature of the degradable superabsorbent composite of the present invention is that the constituent materials are not only degradable because of biodegradability, but also easily disintegrate on the structure to promote more efficient degradation. It has been devised as follows.

The waste of the degradable superabsorbent composite of the present invention can be disposed of according to the properties of the degradable superabsorbent composite. The method is not particularly limited, and any method can be adopted as long as it can make use of the characteristics of the degradable superabsorbent composite, but a method that can be widely used is generally preferable.

The preferred method is a method that utilizes the biodegradability of the degradable superabsorbent composite. Examples of the method include composting, which is a method that makes use of the degradability in compost during biodegradability, and burying, which is a method that makes use of the degradability in soil. However, in addition to these, other intrinsic properties can be used for disposal as long as the function of the degradable superabsorbent composite of the present invention is not hindered. For example, a high-temperature heat treatment utilizing high-temperature decomposability, or a method of chemically treating with a specific chemical. For example, oxidation treatment using oxidative decomposability using an oxidizing agent, reduction treatment using reductive decomposability using a reducing agent, hydrolysis treatment using water and a catalyst that promotes hydrolysis, etc. And alkali treatment using alkali decomposability using an alkali, and acid treatment using acid decomposability using an acid.

The decomposition can be made more efficient by using a process such as stirring, mixing, crushing, shredding, or the like by mechanical means, or by performing it as a pretreatment.

(5-1) Method for Composting the Degradable Superabsorbent Complex Waste The method for composting the degradable superabsorbent complex waste of the present invention has the degradable superabsorbent complex. It can be carried out by expressing in-compost degradability. That is, it means that it is decomposed by bio (organisms) such as microorganisms, bacteria, enzymes, etc. in compost, and becomes a safe low molecule.

In a preferred embodiment, for example, 1 part by weight (dry state) of the degradable superabsorbent complex is charged into 100 parts by weight (wet state) of inoculum (inoculant) of compost (compost), and is charged for 58 days for 40 days. When treated at ℃
The dry weight of the degradable superabsorbent composite after treatment is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment.

The method for composting the decomposable superabsorbent complex waste of the present invention is not particularly limited, but generally, a method utilizing fermentation bacteria, fermentation bacteria and the like is employed. More specifically, fermentation bacteria and bacteria are propagated, and garbage is fermented into a compost by using aerobic decomposition.

[Principle of Compost Treatment] The compost treatment of the decomposable superabsorbent composite waste of the present invention may be performed, for example, by treating the decomposable superabsorbent composite waste used alone in a disposable diaper or the like. It may be processed together with other composted "garbage". In the present invention, a description will be given mainly of a case where the waste is processed together with general “garbage”.

"Green garbage" is 90% of its weight is water, and the remainder is composed of a substance belonging to a polymer system, and its main elements are C, H, O, N and S. In addition, P,
Contains inorganic substances such as Ca, Fe, Zn, K, and Na. The high-molecular components in these are generally decomposed outside the cells into low-molecular components by decomposing enzymes produced by the microorganisms that inhabit, and the inorganic substances are reused as nutrients of the microorganisms again. The weight of the degradable superabsorbent composite waste of the present invention is also 9%.
0% or more is water, and the rest is composed of a substance belonging to a polymer system, and its main components are C, H, O, N, Ca, Na
Etc.

[0216] Various substances of reduced molecular weight are absorbed by bacterial cells and used for the respiratory system. Cells in this process generates CO _2. Then, at this time, the cells synthesize high energy compounds and release water.

This high-energy compound is used as a vital source of microbial growth. In this repetitive process, low-molecular components are decomposed into CO ₂ and water, and in extreme cases, garbage disappears. , Ca, K and other elements and only inorganic substances are left.

That is, a large amount of heat is released by the steps of biological oxidation → synthesis → auto-oxidation. For example,
An aerobic metabolic reaction of glucose, oxidative decomposition of ammonia by nitrifying bacteria, and the like occur. The moisture in the garbage is released by these heat generations.

[Method of Compost Treatment] The method of compost treatment of the decomposable superabsorbent composite waste of the present invention is not particularly limited, and a general treatment method can be used.

For example, there may be mentioned a natural decomposition method, a drying loss method, and an artificial microorganism utilizing method. Among these, an artificial microorganism utilization method is preferable because the speed of fermentation and decomposition is high.

The natural decomposition method is a method in which garbage is slowly fermented and decomposed using various bacteria existing in the natural soil. It does not use a heating device. In order not to use a special fermentation apparatus, it is preferable to adjust the raw material moisture content to around 60%, and it is more preferable to take measures against odor.

This method is carried out in a semi-underground type, a double tank type, or the like in household garbage disposal. Not only natural cells but also various aerobic cells grown artificially can be mixed and added. It is preferable to set the fermentation conditions of this method so as to be suitable for the added cells, and to automatically control the building, the fermenter, and the switching facility.

The drying method is a method for removing 90% or more of water contained in garbage by drying. An electric heater, warm air, steam, or the like can be used for drying the decomposable superabsorbent composite waste of the present invention. Drying can also be carried out by stirring, or by direct heating or indirect heating using a rotating drum.

[0224] In this method, dried compost itself can be used as a moisture adjusting material.

[0225] The object to be dried (dried product) containing the decomposable superabsorbent complex waste of the present invention is not specified as to its use or disposal method. Instead of producing compost itself, dry garbage can be produced and disposed of by incineration or landfill. This will help reduce waste and extend landfill life. Furthermore, the dried product can be composted by adding and fermenting a fermentation promoting cell or the like to the dried product. As described above, the drying method is not intended only for composting, but can reduce the amount and volume of garbage.

The artificial microorganism utilizing system is a system in which an aerobic fermentation / decomposition material in which various artificially grown cells and bacteria are combined is used, and the degradable superabsorbent composite of the present invention is used. It is particularly preferable as a waste composting method.

In the present method, the microorganisms, cells and bacteria to be intentionally added are not particularly limited, but some actinomycetes may be present in the bacteria existing in the soil, such as Thomas, nitrifying bacteria and artificial EM bacteria. What added the like is used. Further, it is preferable to use microorganisms, bacterial cells, bacteria, and the like in the compost obtained by fermenting the degradable superabsorbent complex waste of the present invention and maturing. In order to make these cells work effectively, it is preferable to appropriately control temperature, pH, water content, oxygen content, nutrients and the like. In order to maintain the environment, the heating temperature, stirring, and water content can be controlled by a computer as needed.

In the case of the decomposable superabsorbent complex waste of the present invention, the primary fermentation may be carried out in this manner, and after the secondary fermentation, the waste may be treated at an appropriate place outside the apparatus.

[Operating conditions for compost treatment] Since compost treatment uses cells and the like, proper operation of temperature control, pH control, moisture control,
There is a need to adjust oxygen content, nutrients, etc. In order to maintain this environment, it is preferable to control the heating temperature, stirring, and water content as necessary.

In the composting process, the operating conditions for obtaining high-speed and high-quality compost are as follows: the efficiency of contact between the material and air is increased to ensure air (oxygen) at all times, and the fermentation decomposition products (CO ₂ gas, steam Etc.), keeping the material at a water content and temperature suitable for the inhabitation of microorganisms, finer and homogenizing the material, and increasing the specific surface area to increase the growth efficiency of the microorganisms. Hereinafter, these preferred embodiments will be described.

Before the fermentation of the decomposable superabsorbent complex waste of the present invention, it is preferable to adjust the water content, particle size, useful microorganisms and the like to preferable conditions for compost treatment.

As a raw material for the compost treatment, a lump is not preferable because the contact area with microorganisms is small.
If necessary, pretreatment such as coarse crushing, crushing, shredding, cutting, and fine-graining is performed. For composting, it is necessary to control the water content in the system. In particular, since water evaporates due to heat generation during the composting process, water management is necessary.

Generally, in composting, 40 to 6
A water content of 0% is preferred. In particular, it is preferably about 60%. If the water content is lower than this, the organism becomes less active and the decomposition is slowed down. Conversely, if the water content is excessive, the gaps between the compost materials are filled with water, and oxygen does not sufficiently penetrate, thereby inhibiting aerobic decomposition. In this case, as long as a device capable of sufficiently supplying oxygen is provided, excess water may be used.

For the moisture adjustment in the composting treatment, it is preferable to use sawdust, bark, rice straw, rice hull, dried okara, etc. as a raw material for moisture adjustment in order to increase the surface area and improve the contact with air. . In addition, compost that has aged and has reduced moisture can also be used as a moisture regulator.

Since the composting is performed by aerobic decomposition, it is necessary to supply a sufficient amount of oxygen. If the supply of oxygen is insufficient, it becomes anaerobic, causing the generation of offensive odor, a reduction in decomposition rate, insufficient heat generation, etc., and sterilization cannot be performed due to low temperature.

The supply of oxygen is generally performed by supplying air. The supply of air is preferably performed to such an extent that evaporation of moisture is not promoted. Further, it is preferable to supply the compost raw material uniformly so as not to generate an anaerobic portion.

When organic matter is decomposed at high temperature,
Oxygen consumption is large, so 40-per kg of organic matter
It is preferable to supply 60 liters.

The composting treatment needs to be performed at an appropriate temperature. When the temperature in the system decreases, heating may be performed using an artificial method. A high fermentation temperature is preferable because the decomposition rate of organic matter is increased and pathogenic bacteria are killed.

In continuous composting, the temperature rises in three stages. 40-50 ° C in the first stage, 60-6 ° C in the second stage
It reaches 5 ° C. and 75 ° C. in the third stage. There may be a slight lag period between each step of the temperature rise, or a direct continuous rise. The onset of the lag phase and its duration depend on the type of microorganism at the beginning. The higher the number of microorganisms, the faster the temperature rise occurs, which is preferred. Also, it is preferable to return and add a part of the compost that is undergoing decomposition, because the seeding is performed and the reaction proceeds. When the amount of raw materials is small, heat radiation is more than heat generation. Therefore, it is preferable to keep the fermenter warm.

Composting requires an appropriate nutrient source. When the nutrient source during the compost treatment is insufficient, it is preferable to add the nutrient source. In particular, the nitrogen content, the phosphoric acid content and the like may be insufficient. These nutrients include, but are not particularly limited to, animal residues, livestock manure, and the like.

The fermentation by the cells in the compost depends on the C / N ratio, which is the ratio of carbon to nitrogen. Composting is possible up to a C / N ratio of about 35, but preferably about 16.

The composting treatment needs to be performed under appropriate pH conditions. At the beginning of the composting reaction, the pH is 5.0 to 6.5.
Is preferred. When the pH of the raw material is 5 or less, it is preferable to neutralize with a weak alkali or the like. For example, a method of adding sewage sludge containing a large amount of slaked lime is used.
Further, it is preferable to neutralize highly alkaline substances with a weak acid or the like. For example, it is neutralized by carbon dioxide generated in the process of composting.

In the compost treatment, it is necessary to prevent harmful substances such as harmful heavy metals from being mixed.

[Attachment for Composting] When performing the composting, equipment such as a separator and a deodorizer are provided as necessary.

The raw material for composting is preferably one which does not cause non-uniformity and foreign matter mixing. Therefore, metal fragments are removed by a magnetic separator, and paper and plastic fragments are removed by a wind separator.

In the composting, strong odor is generated in the primary fermentation, and the moisture in the garbage evaporates due to heat generation, and drying proceeds. Thereafter, the water evaporation gradually proceeds in the secondary fermentation, and the secondary fermentation needs to be slowly performed in a building with a roof over a period of one to three months.

In the compost treatment, since a bad odor is generated as described above, it is preferable to use a deodorizing device. For example, there is a method of deodorizing by attaching an appropriate malodor adsorbent, a masking agent, an ozone generator or the like.

As the deodorizing method, there are a combustion method, a chemical reaction method, an ozone decomposition method, an activated carbon adsorption method, a microbial decomposition method (soil method), and the like. The generated bad odor removes ammonia, amine, mercaptan and the like.

A "garbage reduction facility" using waste plastic or paper as a raw material or a "garbage solid fuel conversion facility" may be used in combination.

[Method of Compost Processing] The processing of the generated compost is not particularly limited, and is not particularly limited for home use and business use, and can be used for any of them.

The structure of the home composter is not particularly limited, and various structures can be used. For example, it is a reverse bucket shape without a bottom, an embedded type that is buried in the soil, a double structure type in which the container has a double structure, fermentation is performed at the top of the container, and liquid fertilizer and the like generated are collected at the bottom of the container, In addition, a heater heating method, a drying method, a stirring method, or the like provided with a movable portion or the like can be used. The stirring may be performed manually or electrically.

[0252] In the case of a domestic composter, it is preferable to use a type having a movable portion such as a forced exhaust fan and a deodorizing device and capable of performing automatic processing.

The composting time varies depending on the purpose of composting. For example, in the case of home use, the composting time is 3 to 4 hours if fast processing is desired, and 1 to 2 days or more if high quality compost is desired. Processing is preferred.

The amount of treatment is not particularly limited. However, when the amount of garbage is to be reduced, the amount is set to 1/3 to 1/10 of the input amount.
Those capable of reducing the volume to about or less are preferred.

The commercial composting apparatus is not particularly limited, and various types of composting apparatuses can be used. For example, a fixed tank type, a moving bed type, a trapdoor type, etc., a stirrer-equipped type, a scraping plate type, a rotating cylinder type, such as a stirring and crushing shaft combined type, a single-layer type, a multi-stage type, etc. Fixed stirring shaft type such as horizontal axis rotation type such as single layer type, vertical tank single layer type, multi-stage type, etc., moving stirring axis type such as shovel stirring type, rotating bucket type, horizontal axis stirring type, vertical axis stirring type etc. No. The composting / plant treatment process is not particularly limited, but the separated garbage → crushing →
It is generally performed in a flow of pretreatment → fermentation treatment → product storage → product compost.

Any of a batch system, a continuous system, and a combination thereof may be used.

The size of the processing apparatus is not limited, and may be determined appropriately according to the amount to be processed.

(5-2) Method of burying degradable superabsorbent complex waste The method of burying degradable superabsorbent complex waste of the present invention has the degradable superabsorbent complex. It can be implemented by expressing soil degradability. In other words, it indicates that when subjected to a treatment such as being buried in soil or the like, it is decomposed in the soil by bio (living organisms) such as microorganisms, bacteria, enzymes, etc., and becomes a safe low-molecular compound.

The preferred form is, for example, that 1 part by weight of the degradable superabsorbent composite (in a dry state) is 30
When buried at 0 mm for 6 months, the dry weight of the degradable superabsorbent composite after treatment is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment.

The method of burying the decomposable superabsorbent composite waste of the present invention is not particularly limited, but a method of burying it in a predetermined landfill is generally employed. The landfill is not particularly limited, and may be any of a cut-off type disposal site, a stable type disposal site, and a management type disposal site. However, it is preferable to treat the waste at a management type disposal site for disposing of garbage and the like.

[0261] If necessary, the disposal site may be covered with a roof to prevent rainwater inflow, or to provide perimeter partitioning facilities, corrosion prevention, landslide prevention, subsidence prevention, and water shielding. be able to. In addition, enclosures, culverts, retaining walls, embankments, and the like that prevent children and people from entering can be installed.

[0262] If leachate is generated, it is preferable to provide a water collecting facility and a leachate treatment facility. further,
In order to prevent a fire caused by methane gas generated by the decomposition of organic matter, it is preferable to provide a facility / device for collecting methane gas, a facility / device for burning the same, and the like.

The decomposable superabsorbent composite waste of the present invention comprises:
At the same time, it may be treated together with decomposable wastes or materials such as garbage, wood and paper. These wastes can be covered with soil or the like.

(6) Waste Disposal Method for Sanitary Goods Using Degradable Superabsorbent Complex The waste disposal method for sanitary goods using the degradable superabsorbent composite of the present invention is characterized in that the other constituent materials are as follows. When it is a biodegradable material, it can be treated by the waste treatment method described in (5). In this case, it is preferable that other constituent materials also be easily decomposed.

[0265] Sanitary article waste refers to waste containing a target absorbed body fluid or the like. Pre-processing can be performed as needed to perform the processing of the present invention. For example, a drying treatment, a sterilization treatment, a shredding treatment and the like can be mentioned. In particular,
Shredding is an effective pretreatment because the rate of biodegradability increases. In addition, when used in hospitals and the like, it is an effective method to perform sterilization as a measure against pathogenic bacteria and the like.

[0266] The method for treating waste composed of the biodegradable material of the present invention is not particularly limited. By these treatments, it is preferable that 50 to 100% of the weight of all the constituent elements of the sanitary article is biodegradable, and it is particularly preferable that the biodegradable is 70 to 100%. If the top sheet or back sheet is made of a non-biodegradable material,
After separating and recovering them, it is preferable that 70 to 100% of the remaining total weight is biodegraded, and more preferably 80 to 100%.

It is preferable that the waste of sanitary goods using the decomposable superabsorbent composite of the present invention, when treated with compost, undergoes early biodegradation to become a safe low-molecular compound.
For example, practically, it is preferable that the total weight be 0 to 50% of the weight before processing in 40 days. Further, in 3 weeks, the total weight is 0 to 5 with respect to the weight before processing.
More preferably, it is 0%.

The method of embedding waste of sanitary goods using the decomposable superabsorbent composite of the present invention is not particularly limited, and a commonly used method can be used.

It is preferable that the waste of sanitary goods using the decomposable superabsorbent composite of the present invention is biodegraded early when buried, and becomes a safe low-molecular compound. For example, practically, when buried, the total weight is preferably 0 to 50% of the weight before the processing in 6 months.

(7) Application of degradable superabsorbent composite The degradable absorbent composite of the present invention may be used alone in various forms, for example, tertiary powder, particles, pellets, sheets, or tertiary particles. Although it can be formed into a form such as an original structure, it can also be formed into a sheet shape on an arbitrary sheet-like support such as a non-woven fabric as a base.

The intended use is not particularly limited. For example, sanitary articles, sanitary articles such as sanitary articles, napkins, disposable diapers, incontinence pads, breast milk pads, disposable rags, dressing materials for wound protection, medical supplies such as medical underpads, cataplasms, pet sheets, portable toilets, gel fragrances , Gel, deodorant, sweat-absorbing fiber, disposable body warmers and other daily necessities, shampoos, gels for setting, toiletries such as moisturizers, water retention materials for agriculture and horticulture, life-extending agents for cut flowers, floral foam Agricultural and horticultural products such as seedlings for raising seedlings, nursery beds for raising seedlings, hydroponics vegetation sheets, seed tapes, fluid seeding media, agricultural sheets for preventing dew condensation, freshness retaining materials for food trays, drip absorbent sheets, etc. Transportation materials such as food packaging materials, cold insulation materials, water-absorbent sheets for transporting fresh vegetables, building materials for preventing dew condensation, sealing materials for civil engineering and construction, and mud prevention by shield method Materials, concrete admixtures, civil engineering and construction materials such as gaskets and packing, electronic devices, sealing materials such as optical fibers, waterproof materials for communication cables, materials related to electric devices such as ink jet recording paper, sludge coagulants, gasoline, oil Dehydration of water, water treatment agent such as water remover, printing paste, water swelling toy, artificial snow, sustained release fertilizer, sustained release pesticide,
Sustained-release drugs, humidity control materials, antistatic agents, and the like.

[0272] Among them, it is preferable to use in applications where it is not preferable to absorb or leak a large amount of water. For example, sanitary products, napkins, disposable diapers, incontinence pads, breastfeeding pads, medical underpads, pet seats, toiletries such as portable toilets, nursery beds for nursery, hydroponic vegetation sheets, freshness preserving materials for food trays,
Food packaging materials such as drip-absorbent sheets, transportation materials such as water-absorbent sheets for transporting fresh vegetables, gasoline, dehydration of oils,
Water treatment agents, such as a water removing agent, etc. are mentioned. Furthermore, toiletries such as sanitary products, napkins, disposable diapers, incontinence pads, medical underpads, and pet sheets are particularly preferable.

(8) Application of Degradable Superabsorbent Composite to Sanitary Goods In the present invention, the degradable superabsorbent composite can be used as an absorbent as part of the structure of a sanitary ware.

The structure of the sanitary ware is not particularly limited, and may be a structure used for general sanitary ware. The size of the structure of the sanitary article of the present invention can be selected according to the type, shape, and style of the sanitary article to be used. These are generally based on consisting of a topsheet, a backsheet and an absorbent core.

The degradable superabsorbent composite of the present invention can be used as an absorbent core. Of course, the topsheet and / or the backsheet can also serve as the decomposable superabsorbent composite of the present invention.

When the decomposable superabsorbent composite of the present invention is used as a sanitary product, it may contain other necessary parts as required. For example, in addition to the above parts, disposable diaper supplies include mechanical gatherings such as waist gathers, anti-leak gathers, inner leg gathers, outer leg gathers, frontal tape, adhesive, magic tape, fastener tape systems, release tape systems, and Velcro. A sunning system, a liquid diffusion layer, and the like.

When the decomposable superabsorbent composite of the present invention is used for a sanitary article, the sanitary article may have a structure without a top sheet and / or a back sheet, if necessary. That is, an essential element of the sanitary article of the present invention is the absorbent core, and other sanitary articles including the absorbent core are not particularly limited, and the sanitary article can be constructed by combining various parts.

Further, a single part may have two or more functions at the same time. For example, the absorbing core can have a diffusion function. In addition, top sheet layer /
Composite acquisition layer, end cap / waist gather, release tape / faston tape, composite top sheet, side sheet and inner leg gather, filmless composite with back sheet and absorber And the like.

The sanitary ware using the decomposable superabsorbent composite of the present invention can have not only a single structure but also a multiple structure. In particular, the absorption capacity can be enhanced by the structure in which the absorption cores are stacked. These may be not only the structure of the entire sanitary article but also the structure of each part in a multiplex structure. For example, not only a structure in which a tissue layer / pulp layer / a water-absorbent resin layer is vertically combined, but also a multilayer structure can be formed by combining them.

The sanitary ware using the decomposable superabsorbent composite of the present invention is not specified with respect to a specific type, shape or style of the sanitary ware to be used, and a commonly used one can be selected. That is, the present invention relates to the selection of a specific material of a sanitary ware in which the disposal treatment is taken into consideration. In particular, by using a crosslinked polyamino acid-based resin having high performance as a water-absorbing resin, excellent characteristics can be exhibited as a sanitary article, and a novel method for treating wastes is presented.

For example, as types of sanitary articles, children's paper diapers, adult paper diapers, sanitary napkins, tampons,
Examples include panty liners, sanitary sheets, incontinence pads, and medical blood absorbers. The sanitary articles of the present invention
There is no particular distinction regarding the type, and any type that requires a function as an absorber can be used.

Also, the shape of the sanitary napkin is not specified. For example, in the case of a disposable diaper, examples include a pants type, a pad type, a mechanical fastener system type, and the like.

Similarly, there is no distinction regarding the style of use of sanitary articles using the decomposable superabsorbent composite of the present invention.

Further, the size of a sanitary article using the decomposable superabsorbent composite of the present invention is not particularly limited, either.
The size can be selected according to the type, shape and style of the sanitary article used.

(9) Effect of the degradable superabsorbent composite The features and performance of the absorbent product incorporating the degradable superabsorbent composite obtained in the present invention will also be summarized. When the degradable superabsorbent composite of the present invention is used for an absorbent product,
First, before and during use, it has an extremely thin and compact structure in the non-water-absorbing state, and the crosslinked polyamino acid particles are firmly fixed and stabilized. The amino acid particles do not move, and the crosslinked polyamino acid particles are less likely to fall off and destroy the structure.

Secondly, due to the hydrophilicity of the microfibrillated cellulose and its physical form, the absorption rate is high and no blocking occurs even though the crosslinked polyamino acid particles have a pulp press structure of 90% or more during water absorption. It is.

Third, even after water absorption, the swollen polymer is gently grasped by the network of microfibrillated cellulose to prevent the polymer from falling off.

Fourth, characteristics at the time of disposal after use. The absorbent of the present invention is stable in a stationary state when exposed to excess water, but has the property of disintegrating immediately upon application of shear, and is therefore suitable for flashable product design. Further, microfibrillar cellulose has extremely high cellulase activity, and its structure varies in a short period of time when buried in soil.

[0289]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples. In the following Examples and Comparative Examples, “parts” means “parts by weight”.

In the present invention, (1) the measurement of the water absorption capacity of the resin,
(2) Measurement of the water absorption capacity of the degradable superabsorbent composite and (3) Measurement of the biodegradability of the degradable superabsorbent composite were performed.

(1) Measurement of Water Absorption Capacity of Resin The water absorption capacity of the resin in Examples was measured for physiological saline solution in terms of equilibrium swelling water absorption rate, water absorption rate, water absorption capacity under load, and water retention capacity.

(1-1) Measurement of Equilibrium Swelling and Water Absorption of Resin The equilibrium swelling and water absorption of the resin was measured by a tea bag method. That is, about 0.1 part of the resin is placed in a non-woven tea bag (80 mm × 50 mm), immersed in an excess of the corresponding solution to swell the resin for one hour, and then the tea bag is pulled up and drained for one minute. After the operation, excess water was absorbed by a large amount of tissue paper, and then the weight of the tea bag containing the swollen resin was measured. When the same operation was performed using only the tea bag as a blank, the value obtained by dividing the value obtained by subtracting the weight of the blank and the resin from the weight of the tea bag containing the swollen resin by the weight of the resin was taken as the water absorption (g). / G-resin). The physiological saline is a 0.9% by weight aqueous sodium chloride solution.

(1-2) Measurement of Water Absorption Rate of Resin Using one part of the resin, the water absorption rate was measured by the water demand method.
0 parts of physiological saline was absorbed, and the end point was defined as the point at which water disappeared, and the required time was measured.

(1-3) Measurement of Water Absorption Under Load of Resin Using 1 part by weight of resin, 250 kPa (1.5 kg /
cm ² ), and water was absorbed by a water demand method, and the amount of water absorbed under the load one hour later was measured.

(1-4) Measurement of Water Retaining Amount of Resin Using one part of the resin, the gel which had been subjected to equilibrium swelling and absorption was placed in a centrifuge, and a centrifugal force of 3000 G was applied for 10 minutes to measure the water retaining amount.

(2) Measurement of Water Absorbing Ability of Degradable Superabsorbent Complex The water absorbing ability of the degradable superabsorbent complex was measured for physiological saline and artificial urine, and the saturated water absorption, water absorption speed, and water absorption under load The amount and rewet were performed.

(2-1) Measurement of water absorption rate of degradable superabsorbent composite The measurement of water absorption rate of the degradable superabsorbent composite was carried out using the liquid 2
The absorption rate at which 0 ml was absorbed was measured.

(2-2) Measurement of Saturated Water Absorption of Degradable Superabsorbent Complex The saturated water absorption of the degradable superabsorbent complex was measured by absorbing water by the water demand method and measuring the amount of water absorption one hour later. It was measured.

(2-3) Measurement of Water Absorption Under Load of Decomposable Highly Water Absorbing Composite The water absorption under load of the layered body was measured at 103 kPa (20 g /
Water was absorbed by a water demand method under a load of ² cm ² ), and the amount of water absorbed after 1 hour was measured.

(2-4) Measurement of Wet Back of Degradable Super Absorbent Composite The wet back of the degradable super absorbent composite was measured at 111 kPa (1 ton) after absorbing water by the water demand method and saturated absorption. / M ² ), a large amount of tissue paper was sucked up with the liquid that returned when a load of ² m was applied, and its weight was measured.

(3) Measurement of biodegradability of the degradable superabsorbent composite The biodegradability of the degradable superabsorbent composite in Examples was determined by using the prepared degradable superabsorbent composite by composting. Biodegradability in water, biodegradability by burying, and biodegradability in water were measured.

(3-1) Measurement of biodegradability of the decomposable superabsorbent composite in compost The biodegradability of the absorbent pad in the compost was measured by the compost method. The compost method is based on ASTM D-
ISO CD 14855, an application of 5338.92
It went according to. That is, first, 80
In addition to 0 parts of the inocula, biodegradation was performed at 58 ° C. for 40 days, and the degree of decomposition of the absorbent pad was visually observed. When the non-decomposed product remained, the weight of the taken out decomposition residue was measured, and the change in weight with respect to the original constituent material was represented by the decomposition rate (%).

(3-2) Measurement of biodegradability by burying the decomposable superabsorbent composite The biodegradability of the burying of the absorbent pad was measured by burying the test sample 30 cm from the ground and measuring for 6 months. Biodegradation was performed, and the degree of decomposition of the absorbent pad was visually observed. When the non-decomposed product remained, the weight of the taken out decomposition residue was measured, and the change in weight with respect to the original constituent material was represented by the decomposition rate (%).

(3-3) Measurement of biodegradability of degradable superabsorbent complex in water The biodegradability of degradable superabsorbent complex in water was measured using a culture solution (Dubos medium). It was prepared and used for testing in test tubes. The composition of the culture solution is shown below. These were stirred and dissolved in an autoclave at 120 ° C. for 10 minutes.

Cellulose-degrading microorganisms (microbe
Preparation of s) Decomposition test The decomposable superabsorbent composite and the standard cellulose fiber which were dried in a desiccator for 1 day or more to a constant weight were cut, and 0.5 g each was placed in a 300 ml flask containing 100 ml of the above solution. Then, 500 ml of water was poured therein, and the contents were cultured for two weeks while shaking the contents occasionally.

After the culture, the contents of each flask were washed out, suctioned and filtered on a 47 mm diameter glass filter having a 1 μm diameter through-hole (perforation), and dried at 105 to 110 ° C. for 2 hours. It was dried in a desiccator and weighed. The decomposition rate is [(W _k0 −W _k1 ) / W ₀ ] [W _s1 (W ₀ / (W _s0 −
W _s1 ))].

[Compound Preparation Example 1] 7.2 parts of lysine methyl ester dihydrochloride and 22.6 parts of lysine monohydrochloride were dissolved in 40 parts of distilled water, and 7.8 parts of caustic soda was added little by little. After neutralization, a lysine aqueous solution was prepared. On the other hand, 100 parts of polysuccinimide having a molecular weight of 96,000 was dissolved in 400 parts of DMF under a nitrogen stream, an aqueous lysine solution was added, and the mixture was stirred at room temperature for 1 hour, stopped stirring, and reacted for 20 hours. The reaction product was transferred to a mixer equipped with a blade with stirring blades, and 400 parts of distilled water and 400 parts of methanol were added.
In 5 minutes, the gel was chopped, and 129.7 parts of a 27% by weight aqueous sodium hydroxide solution was added dropwise over 2 hours. After the dropwise addition, the mixture was further stirred for 2 hours, and then the pH was adjusted using 7% by weight aqueous hydrochloric acid.
= 7. After neutralization, further add methanol 30
0 parts were added and the precipitate was dried at 60 ° C. to obtain 143 parts of a water-absorbing polymer. Further, the mixture was pulverized using a sample mill and classified to 100 to 500 μm.

When the water absorption capacity of this resin was measured, the equilibrium swelling absorption was 58 times, the water absorption rate with respect to physiological saline was 27 times per minute, and the water absorption under load was 23. The amount of water was 28 times.

[Compound Production Example 2] 3.0 parts of hexamethylenediamine was dissolved in 40 parts of DMF, and 7.8 parts of caustic soda was added little by little to neutralize to prepare an aqueous lysine solution. On the other hand, under nitrogen stream, 100 parts of polysuccinimide having a weight average molecular weight of 153,000 was dissolved in 400 parts of DMF, a lysine aqueous solution was added to this solution, and the mixture was stirred at room temperature for 1 hour, stopped stirring, and reacted for 20 hours. Thus, a gel of crosslinked polysuccinimide was obtained. The gel of crosslinked polysuccinimide was transferred to a mixer equipped with a blade with a stirring blade, 400 parts of distilled water and 400 parts of methanol were added, and 8000 rpm was added.
The gel was ground for 5 minutes at.

Further, while maintaining the degree of swelling of the resin within the range of 3 to 100 times, 129.7 parts of a 27% by weight aqueous solution of caustic soda was dropped therein over 2 hours. After dropping,
The mixture was further stirred for 2 hours.
Neutralized to H7. After the neutralization was completed, 300 parts of methanol was further added, and the precipitate was dried at 60 ° C. to obtain 125 parts of a crosslinked polyaspartic acid-based resin as a water-absorbing polymer.

When the water absorption capacity of this resin was measured, the equilibrium swelling absorption was 64 times, the water absorption rate for physiological saline was 28 times per minute, and the water absorption under load was 28 times. The water retention was 35 times.

Example 1 Preparation of Microfibrillated Cellulose (MFC) Dispersion A gel 3.0% aqueous dispersion of S-MFC (manufactured by Tokushu Paper Co., Ltd.) was used as a mother liquor, and ethyl alcohol was added thereto. And ion-exchanged water, and the ethyl alcohol / water ratio is 70/3.
0, S-MFC concentration 0.2%, 0.5%, 1
% Of S-MFC dispersion was prepared.

Preparation of S-MFC / Crosslinked Polyamino Acid Particle Coexisting Dispersion In 50 ml of the above three levels of S-MFC dispersion, 60 to 1 of the crosslinked polyamino acid particles produced in Example 1 for compound production were added.
A slurry of S-MFC / crosslinked polyamino acid particle dispersion was prepared by adding 10 g of a 00 mesh classified product.

Formation of S-MFC / Cross-Linked Polyamino Acid Complex While the above dispersion was stirred, the solvent was removed by aspirator depressurization using a glass filter, then applied onto a nonwoven fabric, and dried at 50 ° C. under reduced pressure.

The composite after drying was a soy-like mass. Each of them was wrapped in a fine metal band, hit with a mallet and pulverized, and the mesh sections 40 to 60 were divided and subjected to a water absorption test.

Table 1 shows the water absorption of the crosslinked amino acid particles used and the water absorption of the pulverized S-MFC / SAP composite.

[0317]

[Table 1] Little change in water absorption was observed.

Example 2 Relationship between Microfibrillated Cellulose Concentration and Properties of Degradable Superabsorbent Composite Preparation of Microfibrillated Cellulose Dispersion Preparation of Bacterial Cellulose (BC) Mother Liquid BC (manufactured by BPR) was dissolved in ion-exchanged water to prepare a mother liquor having a solid content of 1.2%. Stirring was performed for 2 hours using a mixer.

Preparation of BC Ethanol / Water Mixed Solvent Dispersion A predetermined amount of mother liquor was taken, and ethyl alcohol and ion-exchanged water were added thereto to prepare a 0.02% to 0.80% BC dispersion. .

Preparation of BC / Crosslinked Polyamino Acid Particle Coexisting Dispersion A BC / crosslinked polyamino acid particle dispersion is prepared by adding 5 g of crosslinked polyamino acid particles to 50 ml of a 0.02% to 0.80% BC dispersion. did. This dispersion formed a precipitate of crosslinked polyamino acid particles when the BC concentration was low,
It became stable at higher concentrations. While stirring with a mixer to adjust the conditions of the system, the stability of the system was maintained.

[0321]

[Table 2] Formation of BC / Cross-Linked Polyamino Acid Complex The above dispersion was filtered on a Buchner funnel (inner diameter: 11 cm) connected to a pressure reducing device, and a nonwoven fabric substrate (TCF4 manufactured by Nimura Chemical)
03, an apparent specific gravity of 0.07 g / cm ³ ), 20 ml of a viscous dispersion was quickly poured onto the base nonwoven fabric, and the solvent was removed under reduced pressure, followed by hot air drying to obtain a composite.

Evaluation of Water Absorption and Water Retention of Degradable Superabsorbent Composite The above degradable superabsorbent composite was immersed in a sufficient amount of physiological saline for 30 minutes, and then subjected to water absorption according to JIS K-7223. The water retention was measured, and the value was converted to the content of crosslinked polyamino acid particles. As a result, the results shown in Table 3 were obtained.

[0323]

[Table 3] (Embodiment 3) FIG. 17 provided with the coating apparatus shown in FIG.
Was used to produce a degradable superabsorbent composite. The materials used are as follows. (1) Microfibrillated cellulose: S-MFC (manufactured by Tokushu Seiyaku Co., Ltd.) (2) Crosslinked polyamino acid particles: those produced in compound production Example 1 (3) Mixed solvent: methanol / water system (5) Sheet-shaped support Two-layer through-air thermal bond web 40 g /
A non-woven fabric having an m ² and an apparent specific gravity of 0.06 and having the following constitution was used.

Upper layer: rayon (4d × 51 mm) 25 g / m ² Lower layer: polylactic acid spunbond web 15 g / m ^{2 While the} above-mentioned sheet-like support 13 was running at a speed of 10 m / min, the above-mentioned (4 ) Was continuously applied with a width of about 10 mm at intervals of 5 mm. Then, after compressing with a roll to remove the solvent, it was dried with hot air. The resulting degradable superabsorbent composite had the properties as shown in Table 4.

The water retention of the decomposable superabsorbent composite was measured according to JIS K-7223. As a result, a water retention amount of 40.2 g per 1 g of the crosslinked polyamino acid particles was shown, and a value almost equivalent to that of the blank was obtained.

Further, as a result of the biodegradability test in the compost, the decomposition rate was very good at 95%. Further, as a result of a biodegradability test by burying, the decomposition rate was as good as 60%.

Example 4 A commercially available ultra-thin paper diaper was used as a blank, the absorbent portion containing a tissue was removed from the diaper, and an absorbent provided with the degradable superabsorbent composite of the present invention was incorporated instead. A sample was prepared.

The absorber incorporated in this sample was manufactured in the following procedure. First, the degradable superabsorbent composite obtained in Example 3 was cut out in the shape and dimensions shown in FIG. On the other hand, a pulp mat with a tissue of about 90 g / cm ² was prepared, and water droplets were sprayed on the pulp mat with a hand spray for home ironing so as to become 2-3 g / cm ^2. Were superposed and pressed with an iron at 140 to 150 ° C.

[0329] Five identical samples were prepared, and for each sample, the absorption amount, water retention amount, and rewet (rewe
t) was measured. Absorption and water retention are JIS K-7
223. Also, 120 ml of physiological saline was poured into the sample three times at 5 minute intervals, and the first, second,
1.33 MPa (12.5 kg
/ Cm ² ) / Rewet under pressure of absorber area,
The rewet amount was measured.

The results of the above test are summarized in Table 4. In addition, the measured value was shown by the average value of 5 samples.

[0331]

[Table 4] From Table 4 above, the sample obtained by incorporating the absorber constituted by using the decomposable superabsorbent composite of the present invention,
Compared with commercial diapers, the weight is about 70% and the thickness is 1 /
Despite being less than 2, the absorption performance was found to be equal or better.

[Compound Comparative Example 1] The crosslinked carboxymethylcellulose having biodegradability was measured for water absorption capacity. The amount of equilibrium swelling and absorption was 36 times, and the water absorption rate for physiological saline was 12 times for 1 minute. The water absorption under load was 12 times and the water retention was 15 times.

[Comparative Example 1 for Production of Degradable Superabsorbent Composite] An absorbent was produced without using a water-absorbing resin, and its absorption capacity was measured. For physiological saline, the water absorption rate was 0.45 ml / sec · cm ² and the rewetting amount was 0.074 g / cm ² .

For artificial urine, the water absorption speed is 0.55 m
l / sec · cm ² and the saturated water absorption is 24 g / cm
² , the water absorption under load was 18 g / cm ² , and the rewetting amount was 0.072 g / cm ² .

[Comparative Example 2 for Production of Degradable Superabsorbent Composite] Using a crosslinked polyamino acid-based resin, an absorbent pad was produced using a nonwoven fabric and a polyethylene for the back sheet, and the biodegradability was measured. In the case of medium and buried, no biodegradation was found except for the pulp in both cases.

[0336]

As described above, according to the degradable superabsorbent composite of the present invention, the water-swellable solid can be formed into various forms, for example, powder, particles, pellets, and sheets. Alternatively, it can be formed into an arbitrary shape such as a three-dimensional structure, so that the handleability can be improved and the range of use can be expanded. In particular, when using crosslinked polyamino acid particles that can be easily obtained at low cost by mass production and stably held in a network structure of microfibrillated cellulose, it is of course possible to use the particles as they are, It is possible to easily configure an absorber of any form. In particular, in the case of a sheet-like configuration, the thickness can be reduced while having a very large water absorption capacity, and the overall thickness of absorbent products such as diapers for infants and adults, sanitary napkins and the like is extremely limited. Can be reduced to When the decomposable superabsorbent composite is supported on another sheet-like support, it can be used in a wide range of applications as a composite having excellent absorbency.

[Brief description of the drawings]

FIG. 1 is a graph showing the relationship between the concentration of microfibrillated cellulose in a solvent and viscosity.

FIG. 2 is an explanatory diagram showing a process of obtaining microfibrillated cellulose from cellulose.

FIG. 3 is a graph showing a relationship between an organic solvent concentration and an absorption ratio of SAP.

FIG. 4 is a longitudinal sectional view of a degradable superabsorbent composite constituting the present invention.

FIG. 5 is a perspective view of an apparatus for producing a degradable superabsorbent composite according to the method of the present invention.

FIG. 6 is a longitudinal sectional view of a degradable superabsorbent composite obtained by the method of the present invention.

FIG. 7 is a diagram showing a process of forming various degradable superabsorbent composites from a slurry dispersion.

FIG. 8 is a cross-sectional view showing a form of a degradable superabsorbent composite according to the first embodiment of the present invention, in which (a) shows a particulate form and (b) shows a flake form.

FIGS. 9A and 9B show a degradable superabsorbent composite according to a second embodiment of the present invention, wherein FIG. 9A is a longitudinal sectional view, and FIG.

FIGS. 10A and 10B show a degradable superabsorbent composite according to a third embodiment of the present invention, wherein FIG. 10A is a longitudinal sectional view, and FIG.

FIG. 11 is a longitudinal sectional view of a degradable superabsorbent composite according to a fourth embodiment of the present invention.

FIG. 12 is a longitudinal sectional view of a degradable superabsorbent composite according to a fifth embodiment of the present invention.

FIG. 13 is a longitudinal sectional view of a degradable superabsorbent composite according to a sixth embodiment of the present invention.

FIG. 14 is a longitudinal sectional view of a degradable superabsorbent composite according to a seventh embodiment of the present invention.

FIG. 15 is a longitudinal sectional view of a degradable superabsorbent composite according to an eighth embodiment of the present invention.

FIG. 16 is a longitudinal sectional view of a degradable superabsorbent composite according to a ninth embodiment of the present invention.

FIG. 17 is a flowchart of a step of producing a degradable superabsorbent composite according to the method of the present invention.

FIG. 18 is a flowchart showing a modification of the step in FIG. 17;

19 is a longitudinal sectional view of another coating apparatus used in the flow shown in FIG.

20 is a plan view of a grooved roll used in the apparatus of FIG.

FIG. 21 is a cross-sectional view of a sheet-like support coated with a mixed solvent layer using the apparatus shown in FIGS. 19 and 20;

FIG. 22 is a diagram showing a method for measuring rigidity (mm).

FIG. 23 is a sectional view taken along the line AA of FIG. 22;

FIG. 24 is a chart showing criteria for determining the binding stability of SAP.

FIG. 25 is a plan view of a degradable superabsorbent composite prepared for incorporation into a sample in Example 4 of the present invention.

[Explanation of symbols]

 Reference Signs List 1 Unwinding roll 2 Spray nozzle for temporary fixing solution 3 SAP supply feeder 4 Spray nozzle for microfibrillated cellulose 5 Heat roll 6 Immobilized SAP layer 7 Super absorbent sheet 10 Degradable super absorbent composite layer 11 Microfibrillated Cellulose 12 SAP particles 13 Sheet support 14 Liquid-impermeable nonwoven fabric 15, 23 Bonding section 16 Channel 21 Liquid-impermeable sheet 22 Highly water-absorbent composite sheet material 24 Channel 31-34 Tank 35-37 Mixer 40 Molding section 41 Belt conveyor 42 Nozzle 43 Roll press 44 Bath 45 Dipping roll 46, 47 Roll 46a Groove 48 Mixed solvent layer 50 Drying section 51, 52 Heating roll 60 Compressing section 61, 62 Press roll 63, 63 'Tube 64, 64' Motor

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (reference) B01J 20/26 A41B 13/02 M 4L055 D21H 27/00 A61F 13/18 300 // A61F 5/44 383 (72) Invention Person Chojiro Higuchi 580-32, Takuji Nagaura, Sodegaura-shi, Chiba Mitsui Chemicals, Inc. (72) Inventor Takeshi Ishitoku 580-32 Takuji Nagaura, Sodegaura-shi, Chiba Mitsui Chemicals, Inc. (72) Persona Suzuki F-term in Japan Absorbent Technology Research Institute, Inc. 2-26-5 Nihonbashi-hama-cho, Chuo-ku, Tokyo AR00A AT00B BA02 DE01A DG01A DG02A DG06B DG10B DG12B DG13B DG15B EA061 EH312 EJ862 GB66 JB10A JB20A JC00 JC00B JD15 JD15A JM10A YY00A 4G066 AB06D AC02B AC26B AC35B AE06B AE20B AE20C BA03 BA05 BA16 BA36 CA43 DA11 DA12 DA13 EA05 FA12 FA21 4L055 AG45 AG46 AG80 AG93 AG94 AG98 AH50 AJ01 BE07 B E09 EA10 EA40 FA20 GA26 GA46

Claims (20)

[Claims] 1. A degradable superabsorbent composite comprising an absorbent layer (A layer) laminated on a support layer (B layer), wherein the absorbent layer (A layer) is a crosslinked polyamino acid particle. (A-
1) A composite comprising at least a part of the surface coated with microfibrillar cellulose (a-2), wherein the support layer (B layer) is a degradable support layer. Degradable super absorbent composite. 2. The degradable superabsorbent composite according to claim 1, wherein at least a part of the degradable support layer is a biodegradable support layer. 3. The degradable superabsorbent composite according to claim 1, wherein at least a part of the degradable support layer is a decomposable support layer in compost. 4. The decomposable support layer in the compost charges 1 part by weight (dry state) of the decomposable superabsorbent complex into 100 parts by weight (wet state) of inoculum (inoculant) of compost (compost). When treated at 58 ° C. for 40 days, the dry weight of the degradable superabsorbent composite after treatment is based on the dry weight of the degradable superabsorbent composite before treatment.
The degradable superabsorbent composite according to claim 3, which has a property of becoming 0 to 50% by weight. 5. The degradable superabsorbent composite according to claim 1, wherein at least a part of the degradable support layer is a soil degradable support layer. 6. The soil-decomposable support layer comprises 1 part by weight (in a dry state) of the degradable superabsorbent complex, and
mm for 6 months, the dry weight of the degradable superabsorbent composite after treatment is 0 to 50% by weight based on the dry weight of the degradable superabsorbent composite before treatment. The degradable superabsorbent composite according to claim 5. 7. The crosslinked polyamino acid particles according to (1),
(2) Absorption capacity of physiological saline in which the equilibrium swelling absorption is 20 to 200 times per unit weight of dry polymer, (2) absorption of physiological saline for 1 minute is 10 to 150 times per unit weight of dry polymer. A certain water absorption capacity, (3) 103k
The water absorption capacity of the physiological saline under a load of Pa (20 g / cm ² ) is 5 to 150 times per unit weight of the dry polymer, and (4) centrifugation of 3000 G into the gel saturated with the physiological saline. The amount of water retention that can be maintained after applying force for 10 minutes is 5 to 15 per unit weight of dry polymer.
The degradable superabsorbent composite according to any one of claims 1 to 5, wherein the composite has at least one of a water absorption capacity of 0 times. 8. The degradable superabsorbent complex according to claim 1, wherein the crosslinked polyamino acid is a crosslinked polyaspartic acid. 9. The microfibrillar cellulose (a)
The degradable superabsorbent composite according to any one of claims 1 to 8, wherein -2) is cellulose or a cellulose derivative. 10. The degradable superabsorbent composite according to claim 1, wherein the microfibrillar cellulose (a-2) is obtained by grinding and / or beating pulp. body. 11. The degradable superabsorbent composite according to claim 1, wherein the microfibrillar cellulose (a-2) is obtained by microbial metabolism. 12. The degradable superabsorbent composite according to claim 1, wherein the degradable support layer is a layer containing a degradable polymer. 13. The decomposition according to claim 1, wherein the decomposable support layer is a layer comprising at least one layer selected from the group consisting of a web, a sheet, and a film. Super absorbent composite. 14. The degradable superabsorbent composite according to claim 13, wherein the web is at least one selected from the group consisting of woven fabric, knitted fabric, nonwoven fabric, and paper. 15. The decomposable superabsorbent composite according to (1):
The absorption rate when absorbing 20 ml of physiological saline,
Water absorption capacity of 0.1 to 50 ml / sec · cm ² ,
(2) When saturated saline is absorbed,
Water absorption capacity of 0.1 to 5 g / cm ² , (3) absorption of 0.05 ml of a physiological saline solution while applying a load of 103 kPa (20 g / cm ² ) is 0.05
Water absorption capacity of 飽和 4 g / cm ² and (4) 111 kPa (1 ton / m ² ) after saturated absorption of physiological saline.
0) 7 g of reversal drainage amount when load is applied
/ Cm ² at a water absorption capacity, and has at least one one of the water absorption capacity of degradable superabsorbent composite according to any one of claims 1 to 14. 16. An absorber layer (A layer) and a support layer (B layer)
In the decomposable superabsorbent composite laminated thereon, the absorbent layer (A layer) is formed of a crosslinked polyamino acid particle (a-
1) Degradability composed of a composite in which at least a part of the surface is coated with microfibrillar cellulose (a-2), wherein the support layer (B layer) is composed of a degradable polymer A method for producing a superabsorbent composite, comprising: a suspension comprising crosslinked polyamino acid particles (a-1), microfibrillar cellulose (a-2), and water and / or a water-miscible organic solvent. A method for producing a decomposable superabsorbent composite, comprising casting on the support layer (layer B) and drying. 17. The water-miscible organic solvent is at least one selected from the group consisting of alcohols having 1 to 6 carbon atoms, glycols, ethers, and ketones.
A method for producing the degradable superabsorbent composite according to claim 16. 18. A crosslinked polyamino acid-based resin, wherein at least a part of the surface is coated with microfibrillar cellulose. 19. A crosslinked polyamino acid-based resin for a decomposable superabsorbent complex, wherein at least a part of the surface is coated with microfibrillar cellulose. 20. A sanitary article comprising the decomposable superabsorbent composite according to claim 1.