TW201726998A - Laminated nonwoven fabric - Google Patents

Abstract

Disclosed is laminated nonwoven fabric (1) which comprises a first outer layer (11), a second outer layer (12) located on the reverse side from the first outer layer (11), and an interlayer (13) located between the first outer layer (11) and the second outer layer (12), wherein the first outer layer (11) and the second outer layer (12) each comprise hydrophobic fibers and hydrophilic fibers but contain no fusion-bondable fibers, the interlayer (13) comprises a pulp and fusion-bondable fibers, the amount of the fusion-bondable fibers being 20 mass% or larger but less than 80 mass% with respect to the whole mass of the interlayer (13), and the interlayer (13) includes portions where the fusion-bondable fibers have been bonded to each other. The laminated nonwoven fabric (1) is not only excellent in terms of the ability to hold an aqueous liquid therein in advance before actual use but also excellent in terms of the ability to gradually release the held aqueous liquid.

Description

Laminated non-woven fabric

The present invention relates to laminated non-woven fabrics. In particular, the present invention relates to a laminated nonwoven fabric excellent in performance of a water-storing liquid and a property of slow release.

Conventionally, in order to clean the surface of various skins such as human skin, furniture, and flooring, a disposable wiping sheet such as a wet wiping cloth obtained by impregnating an aqueous liquid with a non-woven fabric is used. In the wiping sheet, the user who cares for the skin of the human body pays particular attention to the skin feeling. Therefore, in order to ensure the water absorption and the water retention, it is known that the outer layer of the yttrium fiber which is excellent in flexibility and hydrophilicity is disposed on both sides of the intermediate layer mainly composed of pulp (Patent Document 1) ). However, the laminated non-woven fabric having an intermediate layer mainly composed of pulp has an excellent absorbability with respect to an aqueous liquid, but has a problem that it is difficult to release the absorbed aqueous liquid due to high water retention of the pulp. In addition, regarding a disposable wiping sheet such as a wet wiping cloth, when wiping the sheet to wipe the dirt adhering to the surface, for example, wiping the skin adhered to the human body (for example, adhering to the feces of the buttocks), Can be pre-stored with an aqueous liquid to make it sticky In addition to the performance of the aqueous liquid which is required to soften or swell and easily wipe the dirt, it is preferable to increase the water content which is pre-stored when the wiping sheet is pressed against the surface of the wiping object during wiping. The performance of the liquid. By slowly discharging the aqueous liquid from the wiping sheet, it is possible to promote the wiping of the adhered dirt. In the wiping operation of the adhered dirt, when the amount of the aqueous liquid discharged from the wiping sheet is insufficient, it is difficult to soften or swell the adhered dirt, and sometimes it is necessary to blow water to the surface of the wiping target to remove moisture. It is added to the work of wiping the surface of the object. If it is not necessary to add water to the surface of the wiping object, the convenience of wiping the sheet can be improved. In addition, when cleaning the skin of the human body, it is not necessary to blow water to the skin of the human body to stimulate the human body. In addition, in the initial stage of the wiping operation, that is, when the wiping sheet impregnated with the aqueous liquid is brought into contact with the surface to be wiped and compressed on the surface of the wiping target, if the aqueous liquid is excessively released from the wiping sheet, there is a possibility that the wiping sheet may be excessively released. The excess work of applying the discharged aqueous liquid to the surface of the wiping object, or the excessive overflow or dripping of the aqueous liquid before the adhered soil is softened or swollen and wiped. When the aqueous liquid excessively flows out or drip from the skin of the human body, there is a fear of getting wet or contaminating the laundry, which is not preferable.

Patent Document 2 describes a heat-absorbing sheet in which an inner layer containing superabsorbent fibers and a surface layer and an inner layer mainly composed of synthetic fibers are integrated by heat, and the inner layer is Contains high-absorbency fibers that absorb and retain moisture during actual use and then slowly release. However, when moisture is absorbed by the superabsorbent fiber, most of the moisture absorbed by the superabsorbent fiber is absorbed and held by the superabsorbent fiber and is difficult to be released. In addition, highly absorbent fibers due to advance Since the moisture is absorbed, the strength is lowered in actual use, and there is a problem that the sheet cannot withstand the load received during the wiping operation.

The more the amount of the aqueous liquid previously stored in the wiping sheet, and the higher the performance of wiping the sheet to slowly release the aqueous liquid, the more effective the wiping of the larger area, so in the technical field, it is required to be in advance before actual use. The amount of aqueous liquid retained is greater, and the slow release of the aqueous liquid is higher in wiping the sheet.

[Previous Technical Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2005-287894

[Patent Document 2] Japanese Patent Laid-Open Publication No. 2008-155566

Accordingly, an object of the present invention is to provide a non-woven fabric which is excellent in the performance of pre-storing an aqueous liquid before the actual use, and which is excellent in the ability to slowly release the stored aqueous liquid.

The inventors of the present invention have intensively studied to solve the above problems, and have found that the first outer layer, the second outer layer on the opposite side of the first outer layer, and the intermediate layer between the first outer layer and the second outer layer are included. In the layered non-woven fabric, The first outer layer and the second outer layer both contain a hydrophobic fiber and a hydrophilic fiber, and do not contain a heat-fusible fiber; and the intermediate layer contains the pulp and the total mass of the intermediate layer is 20% by mass or more. And less than 80% by mass of the heat-fusible fiber; when the intermediate layer has a portion where the heat-fusible fibers are joined to each other, the storage property with respect to the pre-stored aqueous liquid before use, and the storage of the aqueous liquid are slow Both of the released performance can be improved, thus completing the present invention.

That is, the present invention is a laminated non-woven fabric comprising: a first outer layer, a second outer layer on the opposite side of the first outer layer, and an intermediate layer between the first outer layer and the second outer layer. The laminated non-woven fabric is characterized in that: the first outer layer and the second outer layer both contain hydrophobic fibers and hydrophilic fibers, and both do not contain heat-fusible fibers; the intermediate layer contains pulp and is opposite to the intermediate layer All of the heat-fusible fibers having a mass of 20% by mass or more and less than 80% by mass; the intermediate layer having a portion where the heat-fusible fibers are bonded to each other.

The laminated non-woven fabric of the present invention is excellent in the storage property with respect to the previously stored aqueous liquid before the actual use, and is excellent in the performance of slowly releasing the retained aqueous liquid.

1‧‧‧Laminated non-woven fabric

11‧‧‧1st outer layer

12‧‧‧2nd outer layer

13‧‧‧Intermediate

Fig. 1 is a schematic cross-sectional view showing a laminated non-woven fabric of the present invention.

Fig. 2 is a graph showing the water absorption amount W ₃ , the water retention amount W ₅ and the liquid release amount obtained for the nonwoven fabrics of Examples 1 to 3 and Comparative Examples 1 and 2.

Fig. 3 is a graph showing changes in the amount of liquid discharged from the nonwoven fabrics of Examples 1 to 3 and Comparative Examples 1 and 2.

A part of an embodiment of the invention related to the present invention is as follows.

[Pattern 1]

A laminated non-woven fabric comprising: a first outer layer; a second outer layer on the opposite side of the first outer layer; and a laminated non-woven fabric on the intermediate layer between the first outer layer and the second outer layer, the first outer layer and the second outer layer, Both contain hydrophobic fibers and hydrophilic fibers, and both do not contain heat-fusible fibers, and the intermediate layer contains pulp and heat fusion of 20% by mass or more and less than 80% by mass relative to the entire intermediate layer. The intermediate layer has a portion where the heat-fusible fibers are joined to each other.

According to the above aspect 1, in the intermediate layer, the heat-fusible fibers are joined to each other to form a strong three-dimensional mesh structure, and in the wiping operation, moderate high strength and bulkiness can be ensured with respect to the compressive force. In addition, the aqueous liquid can be stored in the three-dimensional mesh structure in which the heat-fusible fibers are joined to each other. In the space, the pulp contained in the intermediate layer has high water retention property, whereby the non-woven fabric is laminated, and it is excellent in the storage property with respect to the previously stored aqueous liquid before the actual use, and at the same time, the storage of the retained aqueous liquid is excellent. Further, when the first outer layer and the second outer layer contain the heat-fusible fibers, the portions in which the heat-fusible fibers are bonded to each other are likely to be rough, but both the first outer layer and the second outer layer are Since the heat-fusible fiber is not contained, the laminated non-woven fabric of the present invention has an excellent skin feel. When the amount of the heat-fusible fiber is less than 20% by mass based on the total mass of the intermediate layer, it is difficult to form a strong three-dimensional mesh structure by joining the heat-fusible fibers to each other in the intermediate layer. When the amount of the heat-fusible fiber is 80% by mass or more based on the total mass of the intermediate layer, the amount of the pulp contained in the intermediate layer is less than 20% by mass, so that the performance and the performance of retaining the previously stored aqueous liquid are insufficient. Further, since the ratio of the pulp is reduced, there is a decrease in the performance of slowly discharging the aqueous liquid of the intermediate layer.

[Pattern 2]

The laminate nonwoven fabric of the above aspect 1, wherein the hydrophilic fibers in the first and second outer layers are interlaced with the pulp in the intermediate layer.

According to the above aspect 2, since the hydrophilic fibers in the first and second outer layers are interlaced with the pulp in the intermediate layer, when the compressive force is applied to the laminated non-woven fabric during wiping, the aqueous liquid held in advance in the intermediate layer is easily The pulp from the intermediate layer is transferred to the first and second outer layers, and each time the pressure is applied, the aqueous liquid can be slowly released to the surface of the wiping target, such as the skin of the human body.

[Pattern 3]

The laminated non-woven fabric of the above aspect 1 or 2, wherein the laminated non-woven fabric is a dry water needle non-woven fabric.

According to the above aspect 3, it is possible to provide a more excellent skin feel and higher strength.

[Pattern 4]

A laminate non-woven fabric having the same state as in any of the above aspects 1 to 3, wherein the intermediate layer has a higher fiber density (g/cm ³ ) than the first and second outer layers.

According to the above aspect 3, since the intermediate layer has a higher fiber density than the first and second outer layers, the aqueous liquid can be stored in advance in the laminated non-woven fabric before use of the laminated non-woven fabric, and the capillary phenomenon can be obtained from the first And the outer surface of the second outer layer rapidly moves the aqueous liquid to the intermediate layer.

[Pattern 5]

A laminate non-woven fabric having the same state as in any of the above aspects 1 to 4, wherein the heat-fusible fiber has an average fiber length of 3 mm to 8 mm.

When the average fiber length of the heat-fusible fiber is less than 3 mm, it is difficult to make the intermediate layer bulky, and thus it is difficult to improve the storage property with respect to a sufficient amount of the aqueous liquid. The longer the fiber length of the heat-fusible fiber, the higher the tendency of the heat-fusible fiber to align toward the surface direction of the intermediate layer. Therefore, after the heat-fusible fiber is thermally fused, it is difficult to form an intermediate layer having sufficient bulkiness to retain the aqueous liquid. Further, when the ratio of the heat-fusible fibers aligned toward the surface direction of the intermediate layer is too high, the laminated nonwoven fabric is impregnated with the aqueous liquid. When the aqueous liquid is stored in advance in the intermediate layer, when the pulp contained in the intermediate layer absorbs the aqueous liquid and swells, the tendency of the heat-fusible fibers to inhibit the pulp from swelling in the thickness direction of the intermediate layer is increased.

[Figure 6]

A laminate non-woven fabric having the same state as in any of the above aspects 1 to 5, wherein the basis weight of the intermediate layer is 30% or more of the basis weight of the laminated nonwoven fabric.

When the basis weight of the intermediate layer is 30% or more of the basis weight of the laminated non-woven fabric, it is preferable to ensure higher strength and higher bulkiness with respect to compression.

The laminated non-woven fabric of the present invention will be described in detail below with reference to the drawings.

Fig. 1 is a schematic cross-sectional view showing a laminated non-woven fabric of the present invention. As shown in Fig. 1, the laminated nonwoven fabric 1 of the present invention comprises a first outer layer 11, a second outer layer 12 on the opposite side of the first outer layer, and an intermediate layer 13 between the first outer layer and the second outer layer. A three-layer structure of a laminate.

The first outer layer 11 and the second outer layer 12 of the laminated non-woven fabric 1 of the present invention both contain a hydrophobic fiber and a hydrophilic fiber, and do not contain a heat-fusible fiber. In the laminated nonwoven fabric of the present invention, the hydrophilic fibers contained in the first and second outer layers are preferably interlaced with the pulp contained in the intermediate layer. By interlacing the hydrophilic fibers contained in the first and second outer layers with the pulp contained in the intermediate layer, when the laminated non-woven fabric receives a compressive force during the wiping operation, the aqueous liquid can be easily transferred from the intermediate layer to the first and the first 2 outer layer.

Hydrophilic fibers and hydrophobic fibers in the first and second outer layers The mass ratio of the dimension is preferably 50:50 to 20:80, and particularly preferably 30:70 to 40:60. When the ratio of the hydrophilic fibers is less than this range, the aqueous liquid previously stored in the intermediate layer is less likely to penetrate the first and second outer layers and is difficult to reach the surface to be wiped. Further, in the wiping operation, it is difficult to absorb the aqueous liquid containing the stain. When the ratio of the hydrophilic fibers exceeds this range, the slow release property is lowered.

The type of the hydrophilic fibers contained in the first and second outer layers is not particularly limited, and examples of the hydrophilic fibers include cellulose fibers from the viewpoints of liquid diffusibility, strength, flexibility, and versatility. For example, natural fibers such as cotton, recycled fibers such as strontium and cuprammonium, and the like can be given. Among these, the ruthenium fiber can be particularly preferably used from the viewpoints of liquid diffusibility, strength after interlacing, ease of handling, and versatility. The form of the hydrophilic fibers contained in the first and second outer layers is not particularly limited, and a circular cross-section may be used, or a profiled cross-section such as a Y-shape, a cross shape, or a hollow shape may be used, or such a form may be combined. And use. When the hydrophilic fiber contains a fiber having a profiled cross section, since the fiber of the profiled cross section has a large surface area and excellent liquid absorbency, the liquid diffusibility of the fiber assembly forming the first and second outer layers can be further improved. The hydrophilic fiber is preferably contained in an amount of 50 to 20% by mass, particularly preferably 40 to 30% by mass, in the first and second outer layers.

The hydrophilic fibers contained in the first and second outer layers preferably have an average fiber length of 30 mm to 60 mm. When the average fiber length of the hydrophilic fibers is in this range, the capillary phenomenon of the fiber assembly forming the first and second outer layers can be applied, and the aqueous liquid previously stored in the intermediate layer can be quickly applied. Spread quickly on the surface of the wiped object. The "average fiber length" of the hydrophilic fibers contained in the first and second outer layers means "A7.1.1 A method according to "A7.1 fiber length measurement" in Appendix A of JIS L 1015:2010. (Standard method) The average fiber length measured by the method of measuring the length of each fiber on a glass plate with a scale. The above method is equivalent to the test method of ISO 6989 issued in 1981. The average fiber length of the hydrophilic fibers contained in the first and second outer layers and the heat-fusible fibers contained in the intermediate layer described below is also defined in the same manner as the average fiber length of the hydrophilic fibers. The hydrophilic fibers contained in the first and second outer layers preferably have a fineness of 1.0 to 3.0 dtex. When the fineness of the hydrophilic fiber is less than 1.0 dtex, it is difficult to form a mesh by a card, so there is a problem that productivity is lowered. When the fineness of the hydrophilic fiber exceeds 3.0 dtex, there is a problem that it is difficult to develop a capillary phenomenon. .

Examples of the hydrophobic fibers contained in the first and second outer layers include thermoplastic fibers such as polyethylene, polypropylene, nylon, and polyester, or composite fibers in which these thermoplastic fibers are combined. The hydrophobic fiber is preferably a polyester fiber such as polyethylene terephthalate from the viewpoint of strength at the time of wetting, bulkiness, flexibility, and the like. The hydrophobic fibers contained in the first and second outer layers preferably have an average fiber length of 30 mm to 60 mm. When the average fiber length of the hydrophobic fibers is in this range, the web can be easily formed by a card. The hydrophobic fibers contained in the first and second outer layers preferably have a fineness of 0.6 to 2.2 dtex. When the fineness of the hydrophobic fiber is less than 0.6 dtex, it is difficult to form a mesh by a card, so there is a problem of reduced productivity. When the fineness of the hydrophobic fiber exceeds 2.2 dtex, there will be The problem of hard touch.

The first and second outer layers may be a fiber web formed by a method such as an air laying method, but at least one of the first outer layer and the second outer layer is preferably a comb formed by a carding machine. Cotton mesh. When the first outer layer, the intermediate layer, and the second outer layer are integrated, the first outer layer, the intermediate layer, and the second outer layer can be integrated by a high-pressure water flow such as water spray or the like described later. The fibers in the respective fiber layers and the fibers between the fiber layers are sufficiently interlaced with each other. The form of the card web is not particularly limited, and may be any of a parallel mesh, a cross mesh, and a messy mesh.

The first and second outer layers of the present invention may be a fiber layer having the same structure (that is, a fiber type, a blending ratio, and a fiber layer having the same structure) or a fiber layer having a different structure (that is, a fiber type and blending). At least one of the rate and the structure of the layer is a different fiber layer). The first and second outer layers preferably have a fiber density of 0.02 to 0.06 g/cm ³ independently. When the fiber density of the first and second outer layers is less than 0.02 g/cm ³ , the rough touch caused by the portions where the heat-fusible fibers in the intermediate layer are joined to each other is easily passed through the first and second outer layers. I feel that there is a problem of a non-woven fabric that becomes a poor touch of the skin. When the fiber density of the first and second outer layers exceeds 0.06 g/cm ³ , there is a problem that the movement of the aqueous liquid between the intermediate layer and the outer layer becomes slow. The fiber density of the first and second outer layers can be determined from the thicknesses of the first and second outer layers obtained from the electron micrographs and the basis weights of the first and second outer layers.

The intermediate layer contains pulp and hot-melt fibers having a total mass of 20% by mass or more and less than 80% by mass relative to the intermediate layer dimension. Further, the intermediate layer has a portion where the heat-fusible fibers are joined to each other. The content of the heat-fusible fiber in the intermediate layer is preferably 20% by mass to 50% by mass, particularly preferably 20% by mass to 40% by mass. The content of the pulp of the intermediate layer is more than 20% by mass and 80% by mass or less, preferably 50% by mass to 80% by mass, and particularly preferably 60% by mass to 80% by mass based on the total mass of the intermediate layer. In the intermediate layer, the more the content of the heat-fusible fiber, the more the bulkiness of the intermediate layer can be increased, that is, the volume of the space in which the aqueous liquid can be stored, but the more the content of the heat-fusible fiber, the pulp The less the content. Therefore, when the content of the heat-fusible fiber having a lower hydrophilicity than the pulp is 80% by mass or more, the amount of the aqueous liquid held in the intermediate layer is also reduced in response to the decrease in the pulp content.

The heat-fusible fiber preferably has a fineness of 1.0 to 5.0 dtex, and particularly preferably has a fineness of 1.3 to 2.2 dtex. When the fineness is less than 1.0 dtex, the dispersibility may be deteriorated during foaming. When the fineness exceeds 5.0 dtex, the number of fibers is small, so that it is difficult to form a space for holding the aqueous liquid in the intermediate layer. The heat-fusible fiber preferably has a fiber length of 1 to 12 mm, and particularly preferably has an average fiber length of 3 to 6 mm. When the average fiber length is less than 1 mm, since it is difficult to form a three-dimensional mesh structure in the intermediate layer, there is a fear that a space for storing the aqueous liquid cannot be formed. When the fiber length exceeds 12 mm, the heat-fusible fiber may not be uniformly dispersed and foamed. Doubt.

The type of pulp contained in the intermediate layer is not particularly limited. Examples of the pulp, wood pulp, for example, coniferous wood pulp and broad-leaved wood pulp, and non-wood pulp, for example, rice straw pulp, bagasse pulp, reed pulp, kenaf pulp, mulberry pulp, bamboo pulp, and hemp pulp can be cited. , cotton pulp (such as cotton wool) and so on. Above paper The slurry may be a non-beating pulp which has not been beaten, or a beaten pulp which is subjected to beating treatment, or a combination thereof. From the point of view of the performance of pre-storing an aqueous liquid before actual use, the ability to slowly release an aqueous liquid during actual use, the performance of absorbing a liquid containing liquid during actual use, flexibility, ease of handling, etc. Good for coniferous wood pulp and broad-leaved wood pulp.

Examples of the heat-fusible fiber include a thermoplastic resin having a low melting point such as a polyethylene resin or a low-melting polypropylene at least on the surface, and examples of the heat-fusible fiber include a single-component fiber of a polyethylene resin. a single-component fiber of a polypropylene resin; a core-sheath type composite synthetic fiber having a core portion of a polyethylene terephthalate resin and a sheath portion; a core portion of a polypropylene resin and a sheath portion of a polyethylene resin; a core-sheath type composite synthetic fiber; a core-sheath type composite synthetic fiber having a core of a high-melting-point polypropylene resin and a sheath portion of a low-melting-point polypropylene resin; and a polyethylene terephthalate resin and a polyethylene resin A composite synthetic fiber having a side-by-side configuration; a composite synthetic fiber of a side-by-side type composed of a polypropylene resin and a polyethylene resin. The heat fusible fibers exemplified generally have a lower hydrophilicity than the pulp.

For example, after forming the nonwoven fabric by integrating the first outer layer, the intermediate layer, and the second outer layer by a high-pressure water flow such as water spray as described later, the obtained nonwoven fabric is heat-treated to make the heat-fusible fiber low. When the melting point resin is melted to fuse the heat-fusible fibers to each other and thereby bonding the laminated non-woven fabric of the present invention, the heat-fusible fibers are joined to each other to form a strong three-dimensional mesh structure and heat. Before melting In comparison, the strength of the non-woven fabric can be improved, especially at the time of wetting, and in addition, moderate strength and bulkiness can be ensured with respect to the compressive force during the wiping operation. Furthermore, the aqueous liquid can be stored in a space in the three-dimensional mesh structure in which the heat-fusible fibers are joined to each other, and the pulp contained in the intermediate layer has high water retention property, whereby the non-woven fabric is laminated, and is pre-stored before actual use. The aqueous liquid is excellent in storage property, and at the same time, it is excellent in the ability to slowly release the retained aqueous liquid.

The intermediate layer preferably has a higher fiber density than the first and second outer layers. The intermediate layer preferably has a fiber density of 0.04 to 0.25 g/cm ³ . The intermediate layer has a higher fiber density than the first and second outer layers, and when the aqueous liquid is impregnated into the laminated non-woven fabric of the present invention, the aqueous liquid can be quickly formed by the capillary phenomenon in the first and second outer layers. The ground is moved to the intermediate layer and the aqueous liquid is stored in the intermediate layer. The fiber density of the intermediate layer can be determined from the thickness of the intermediate layer obtained from the electron micrograph and the basis weight setting value of the intermediate layer.

Next, a method of producing the laminated nonwoven fabric of the present invention will be described.

The laminated non-woven fabric of the present invention can be produced by a method comprising at least the following steps: (1) a step of supplying a fibrous web comprising a hydrophilic fiber and a hydrophobic fiber for forming a first outer layer, and (2) a step of forming an intermediate layer of the intermediate layer containing the pulp and the heat-fusible fiber onto the fiber web, and (3) supplying the fiber mesh containing the hydrophilic fiber and the hydrophobic fiber for forming the second outer layer Step to the intermediate layer mesh to obtain the laminated body (4) a step of applying high-pressure water flow treatment from both sides of the laminated body to interweave fibers between the fiber layers, and (5) heat-treating the laminated body to dry the laminated body while heat-melting The step of joining the fibers to each other.

More specifically, the hydrophilic fiber and the hydrophobic fiber are directly or after the cotton blending process to form a fiber web having a form such as a card web, and then the formed fiber is transported by a card or the like. a mesh sheet on which an intermediate layer web for forming an intermediate layer containing pulp and heat-fusible fibers is supplied to the fiber web by an air laying machine or the like, and then formed into a form having a card web The fiber web of the first outer layer containing the hydrophilic fiber and the hydrophobic fiber is supplied onto the intermediate layer mesh to obtain a laminate, and then a high-pressure water flow treatment such as water spray is applied from both sides of the laminate. At least the fibers between the fiber layers are interlaced with each other, and the first outer layer, the intermediate layer, and the second outer layer are integrated with each other.

The non-woven fabric thus obtained has a structure in which fibers in the respective fiber layers and fibers in the fiber layers are interlaced by a high-pressure water flow such as water spray, thereby having excellent sheet strength and liquid diffusibility, and at the same time, 2 In the outer layer, the transfer of the aqueous liquid which spreads in the direction of the non-woven fabric to the intermediate layer can be promoted. Further, since the first and second outer layers which have been transported by the aqueous liquid to the intermediate layer can absorb the aqueous liquid again and diffuse in the direction of the surface, the absorption of the aqueous liquid and the diffusion in the outward direction can be repeatedly performed in the nonwoven fabric. The process of transporting the intermediate layer and increasing the diffusion area of the aqueous liquid or remaining by the continuous diffusion of the aqueous liquid The amount of aqueous liquid that is not woven.

In the first and second outer layers, when a part of the constituent fibers of the fiber layer of at least one of the first and second outer layers is introduced into the inner layer by a high-pressure water flow such as water spray or the like, Since it is easy to transport the aqueous liquid which diffused in the surface direction of the non-woven fabric to the intermediate layer, the absorption of the aqueous liquid, the diffusion in the forward direction, and the transfer to the intermediate layer can be performed more quickly in the laminated non-woven fabric. As a result, the diffusion speed and the diffusion area (diffusion area) of the aqueous liquid in the nonwoven fabric can be further increased.

In the laminated nonwoven fabric of the present invention, the basis weight of the first and second outer layers is determined from the state of formation of interlacing between the fibers of the respective layers, or the softness, the touch of the skin, the diffusibility of the aqueous liquid, and the strength of the sheet. Preferably, they are each independently located in the range of 5 to 15 g/m ² . The basis weight of the intermediate layer is preferably in the range of 10 to 50 g/m ² . The basis weight of the intermediate layer is preferably 30% or more of the basis weight of the laminated non-woven fabric from the viewpoint of the storage property of the aqueous liquid and the slow release property of the aqueous liquid.

The aqueous liquid impregnated in the laminated non-woven fabric of the present invention is water or a liquid containing water as a main component, and the composition can be determined depending on the use. For example, when aiming at the buttocks of infants and young children, a mixture of 10% by weight of propylene glycol and 90% by weight of water, or 7% by weight of propylene glycol and 0.3% by weight of p-oxybenzoate and 92.7% by weight of water can be used. The mixture is impregnated with a tissue paper. The amount of impregnation at this time is more suitably 150 to 300% of the dry weight of the sanitary napkin.

The laminated non-woven fabric of the present invention, except for the wet wiping cloth In addition, various wiping sheets such as wet tissues can be used. In addition, the present invention is not limited to the above-described embodiments and the following embodiments, and may be appropriately modified without departing from the spirit and scope of the invention.

[Examples]

The invention is described in more detail below based on examples, but the invention should not be construed as limiting.

<Comparative Example 1>

A ruthenium fiber (Corona (registered trademark) manufactured by Daiwabo Rayon Co., Ltd.) having a fineness of 1.4 dtex and a fiber length of 4.4 mm as a hydrophilic fiber, and a polydide having a fineness of 1.3 dtex as a hydrophobic fiber and a fiber length of 3.8 mm. Ethylene phthalate (PET) fiber (70W manufactured by Toyobo Co., Ltd.), mixed with a mass ratio of rayon fiber:PET fiber=25:75, using a card with a set basis weight of 10 g/m ² forming a carding web. This carded web was used as the first outer layer. While the obtained carded web was transported, pulp (NB401 manufactured by Weyerhaeuser Co., Ltd.) was supplied onto the card web at a set basis weight of 20 g/m ² to form an intermediate layer, and then produced in the same manner as the first outer layer. The card web is supplied onto the obtained intermediate layer to form a second outer layer, and a laminate comprising the first outer layer, the intermediate layer and the second outer layer is obtained. Water is sprayed from both sides of the laminated body while the obtained laminated body is transported at a transport speed of 20 m/min (water pressure at the first outer layer side: 7 MPa, water pressure at the second outer layer side: 5 MPa, nozzle diameter) : 92 μm, nozzle pitch: 0.5 mm, 2 columns) high-pressure water flow treatment, whereby the constituent fibers in the respective fiber layers and between the fiber layers are interlaced, thereby obtaining the first outer layer, the intermediate layer and the second outer layer. The laminated layer of the 3-layer structure is not woven. The first outer layer side was heated to 125 ° C by a dryer, and the second outer layer side was heated to 135 ° C to dry the obtained laminated nonwoven fabric.

<Example 1>

Pulp (Byner, manufactured by Weyerhaeuser Co., Ltd.) and PE/PP fiber (core manufactured by ES FIBERVISIONS Co., Ltd.) having a core-sheath structure in which the core component of the heat-fusible fiber is polypropylene (PP) and the sheath component is polyethylene (PE). AL-Adhesion, fineness 1.7 dtex, fiber length 3 mm), mixed in a pulp:PE/PP fiber=80:20 mass ratio, and then supplied to the carding web forming the first outer layer, thereby forming an intermediate layer, Otherwise, a laminate non-woven fabric was produced in the same manner as in Comparative Example 1. The heat-fusible fibers contained in the intermediate layer are fused to each other by heating while the laminated nonwoven fabric is dried.

<Example 2>

A laminated non-woven fabric was produced in the same manner as in Example 1 except that the mass ratio of the pulp to the PE/PP fibers was pulp: PE/PP fiber = 60:40.

<Example 3>

A laminated non-woven fabric was produced in the same manner as in Example 1 except that the mass ratio of the pulp to the PE/PP fibers was pulp: PE/PP fiber = 40:60.

<Comparative Example 2>

A laminated non-woven fabric was produced in the same manner as in Example 1 except that the mass ratio of the pulp to the PE/PP fibers was pulp: PE/PP fiber = 20:80.

With respect to each of the laminated nonwoven fabrics of Examples 1 to 3 and Comparative Examples 1 and 2 obtained above, the basis weight (g/m ² ), the thickness (mm), and the specific volume (cm ³ /g) were determined by the following methods. , storage and slow release.

[base weigh]

Ten samples of 100 mm × 100 mm size were collected, and the mass of each sample was measured. Next, the value of mass (g) / area (m ² ) was calculated as the basis weight (g/m ² ) for each sample. The average value of the basis weight of the total of 10 samples was calculated as the basis weight of each example.

[thickness]

The thickness of the non-woven fabric was measured using THICKNESS GAUGE UF-60 manufactured by Daiei Scientific Seiki Co., Ltd. In UF-60, the diameter of the measurement surface was 44 mm, and a pressure of 0.3 kPa was applied to the nonwoven fabric, and the thickness was measured.

[specific volume]

The specific volume of the non-woven fabric is calculated by dividing the thickness of the nonwoven fabric by the basis weight.

[Retention and slow release]

The properties (storage property) and the slow release property (slow release property) of the aqueous storage liquid of the laminated non-woven fabrics produced in Examples 1 to 3 and Comparative Examples 1 and 2 were evaluated by the following two test methods.

<Test Method 1>

Step 1: From the laminated non-woven fabrics produced in Examples 1 to 3 and Comparative Examples 1 and 2, samples each having a length of 140 mm and a width of 60 mm were respectively taken, and the initial mass of each sample was measured by an electronic balance (W). ₀ ), and the following steps 2 to 6 were carried out for each sample.

Step 2: The sample was placed on a plain woven metal mesh having a mass of 57.0 g (W ₁ ), a wire diameter of 0.29 mm and a mesh size of 20 mesh, and the sample and the metal mesh were entirely immersed in a disk containing ion-exchanged water.

Step 3: Pull the sample and the metal mesh one by one from the ion exchange water and place it for 5 minutes while keeping the metal mesh horizontal.

Step 4: In the state where the sample is placed on the metal mesh, the total mass (W ₂ ) of the sample and the metal mesh is measured by an electronic balance, and the total of W ₀ and W ₁ is deducted from W ₂ to obtain The amount of water absorbed by the sample (W ₃ ).

Step 5: The sample after water absorption is placed on the top surface of the SUS304 square pedestal placed on the horizontal plane so that the entire surface of the sample (the lower surface) is in contact with the entire upper surface of the pedestal (140 mm long × 60 mm horizontal) A weight of 840 g of SUS304 (140 mm in length × 60 mm in width) was placed on the opposite side (upper surface) of the sample so that the entire upper surface of the sample was in contact with the entire lower surface of the sample. After placing the sample for 3 minutes, remove the weight.

Step 6: The mass (W ₄ ) of the sample is measured by an electronic scale, and (W ₀ ) is subtracted from (W ₄ ) to obtain a water retention amount (W ₅ ).

The above steps 1 to 6 were carried out at a temperature of 20 ° C and a relative humidity of 60%.

The value of the water absorption amount W _{3 and} the value of the water retention amount W _{5 and} the value obtained by subtracting W ₅ from W _{3 are} taken as the liquid release amount W ₆ (W ₆ =W ₃ -W ₅ ), together with Table 1 below. In Fig. 2, the water absorption amount (W ₃ ), the water retention amount (W ₅ ), and the liquid release amount (W ₆ ) of the first table are shown by a graph.

<Test 2>

Step 1: From the laminated non-woven fabrics produced in Examples 1 to 3 and Comparative Examples 1 and 2, rectangular samples each having a length of 200 mm and a width of 150 mm were respectively taken, and the initial mass of each sample was measured by an electronic balance (W _A ). The long side of each sample was folded in half to a size of 150 mm × 100 mm, and ion-exchanged water having twice the mass of the initial mass W _A of each sample was impregnated into the sample.

Step 2: 10 sheets of 50 mm × 50 mm filter paper (Quality Filter Paper No. 2 manufactured by Advantec Toyo Co., Ltd.) were superposed to obtain a filter paper laminate, and the mass (W _B1 ) of the filter paper laminate was measured in advance, and the filter paper laminate was measured. Overlap on the sample.

Step 3: On the filter paper laminate which is superposed on the sample, a weight having a mass of 360 g (length 30 mm × width 30 mm) is placed, thereby pressurizing the filter paper laminate at a pressure of 4.0 kgf/cm ² for 2 seconds. After removing the weight, the mass (W _C1 ) of the filter paper laminate is measured, and the liquid (ion exchange water) release amount W _D1 (= W _{C1 -} W _B1 ) discharged from the sample to the filter paper laminate is obtained. The amount of liquid released once.

Step 4: Repeat steps 2 and 3 above for the sample after step 3, thereby obtaining the second liquid discharge amount W _D2 .

Step 5: Repeat steps 2 and 3 above for the sample after step 4, thereby obtaining the third liquid discharge amount W _D3 .

Step 6: Repeat steps 2 and 3 above for the sample after step 5, thereby obtaining the fourth liquid discharge amount W _D4 .

Step 7: Repeat steps 2 and 3 above for the sample after step 6, thereby obtaining the fifth liquid discharge amount W _D5 .

Step 8: Repeat steps 2 and 3 above for the sample after step 7, thereby obtaining the sixth liquid discharge amount W _D6 .

Step 9: Repeat steps 2 and 3 above for the sample after step 8, thereby obtaining the seventh liquid discharge amount W _D7 .

Step 10: Repeat steps 2 and 3 above for the sample after step 9, thereby obtaining the eighth liquid discharge amount W _D8 .

Step 11: Repeat steps 2 and 3 above for the sample after step 10, thereby obtaining the liquid discharge amount W _{D9 of} the ninth time.

Step 12: Repeat steps 2 and 3 above for the sample after step 11, thereby obtaining the liquid discharge amount W _{D10 of} the tenth time.

The above steps 1 to 12 were carried out at a temperature of 20 ° C and a relative humidity of 60%. Further, in the above steps 4 to 12, a brand new filter paper laminate produced by the method described in the step 2 was used.

The total amount of liquid release amounts W _D1 ~ W _D10 and W _D1 ~ W _D10 is converted to a value of 40 g/m ² (i.e., the measured liquid release amount × 40 (g/m ² ) / measured basis weight The value of (g/m ² )), and the converted value is shown in the second table. In Fig. 3, the liquid discharge amounts W _D1 to W _{D10 of} the second table are displayed in a graph.

From the first and second tables, and the first and second figures, the laminated non-woven fabrics of the first to third embodiments of the present invention can be found, and Comparative Example 1 and Compared with the non-woven fabric of 2, the water absorption amount (that is, the storage property) is high, and even if the pressure is repeatedly applied, the high water retention property can be maintained, and the performance of allowing a larger amount of water to be slowly released is excellent. The first liquid discharge amount of each of Examples 1 to 3 was a high level of about 1.3 times the first liquid discharge amount of Comparative Examples 1 and 2.

[Industrial Applicability]

The laminated non-woven fabric of the present invention has excellent performance in pre-storing an aqueous liquid before actual use, and at the same time, has excellent performance in slowly releasing the retained aqueous liquid, and therefore is used as a skin for cleaning the human body, or a furniture or a floor. A disposable wiping sheet such as a wet wipe on the surface of various articles.

1‧‧‧Laminated non-woven fabric

11‧‧‧1st outer layer

12‧‧‧2nd outer layer

13‧‧‧Intermediate

Claims (6)

A laminated non-woven fabric comprising: a first outer layer; a second outer layer on the opposite side of the first outer layer; and a laminated non-woven fabric interposed between the first outer layer and the second outer layer, wherein the first outer layer And the second outer layer, both of which contain a hydrophobic fiber and a hydrophilic fiber, and do not contain a heat-fusible fiber; and the intermediate layer contains the pulp and the total mass of the intermediate layer is 20% by mass or more and is not Up to 80% by mass of the heat-fusible fiber; the intermediate layer has a portion where the heat-fusible fibers are joined to each other. The laminate of claim 1 is a nonwoven fabric in which the hydrophilic fibers in the first and second outer layers are interlaced with the pulp in the intermediate layer. The laminate of claim 1 or 2 is non-woven, wherein the laminated non-woven fabric is a dry water needle non-woven fabric. The laminate of claim 1 is non-woven, wherein the intermediate layer has a higher fiber density (g/cm ³ ) than the first and second outer layers. The laminate of claim 1 is non-woven, wherein the heat-fusible fiber has an average fiber length of from 3 mm to 8 mm. The laminate of claim 1 is non-woven, wherein the basis weight of the intermediate layer is 30% or more of the basis weight of the laminated nonwoven fabric.