JP2986663B2 - Hot water size surface sizing composition for papermaking and surface sizing method using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a surface sizing agent for papermaking and a surface sizing method using the same. More specifically, a ketene dimer sizing agent and a water-soluble polymer are used as a surface sizing composition for a surface sizing method of paper or paperboard that does not require surface paper strength from oxidized starch applied during surface coating. The present invention relates to a paper-making surface sizing agent and a surface sizing method that reduce contamination of a papermaking apparatus, improve operability, and improve paper quality by using a compound in combination with a fixed ratio.

[0002]

2. Description of the Related Art Conventionally, sizing of paper and paperboard has been performed to impart functions such as sizing properties, water resistance and waterproofness to paper. For sizing of paper and paperboard, acidic sizing using rosin or reinforced rosin (maleinated rosin) and aluminum sulfate is generally performed.
In contrast, in recent years, white water has been closed in the papermaking process,
Neutral sizing has been introduced from the viewpoint of use of inexpensive and high-whiteness calcium carbonate as a filler, use of broke containing the same, and coat-broking. As sizing agents used for this neutral sizing, ketene dimer sizing agents, substituted cyclic dicarboxylic anhydride sizing agents, etc. are known, but simplicity in use and strong sizing by addition of a small amount are known. Ketene dimer sizing agents are widely used because of their promise.

On the other hand, sizing methods include an internal sizing method in which a sizing agent is added to a pulp slurry before a paper layer is formed in a paper or paperboard making process, and a sizing agent is applied to the surface of paper after the paper layer is formed. There is a surface sizing method. It is known that the internal sizing method is susceptible to the hardness and water temperature of paper-making water and hardly produces a sufficient sizing effect as white water is closed in recent years. Further, it is known that the surface sizing method is hardly affected by papermaking water, has a high yield of the sizing agent, and is easy in process control.

As the surface sizing agent, anionic water-soluble high-molecular substances such as anionic styrene-based polymers and anionic acrylamide-based polymers have been used. If only the sizing is pursued, a ketene dimer sizing agent which exhibits excellent sizing properties not only for neutral paper but also for acidic paper is selected.

[0005]

However, the use of a ketene dimer sizing agent as a surface sizing composition still has the following disadvantages.

Normally, in the process of producing paper or paperboard, surface sizing is performed by applying a surface sizing agent to the paper surface after forming a paper layer using a size press, a size tab, a gate roll coater, a calender, or the like, and drying if necessary. I do. This surface sizing, in addition to imparting size to the paper, starch derivatives such as starch and oxidized starch, cellulose derivatives such as carboxymethyl cellulose, polyvinyl alcohol and polyvinyl alcohol for the purpose of increasing the surface strength of the paper and improving printability A natural or synthetic water-soluble polymer such as anion-modified polyacrylamide is used at a concentration of 5 to 15% by weight, and a sizing agent or the like is further added to the coating solution. It is customary to apply while circulating a part.

The surface sizing method of the present invention is different from the conventional method in that the surface sizing of paper or paperboard does not require the application of paper surface strength from oxidized starch or the like applied during surface coating.
(Hereinafter, in the present invention, a method of sizing with such a coating solution composed of a small amount of a sizing composition and water is referred to as "hot water size"). When a ketene dimer sizing agent is added to a coating solution in a paper or paperboard manufacturing process,
Aggregates are generated due to mechanical shearing force due to high temperature and liquid circulation, and furthermore, chemicals and fillers added to paper in the circulating liquid are eluted into sediments, and these sediments and ketene dimer Aggregates increase due to interaction with. This becomes the residue and stains occur on paper machine parts such as coating rolls.
The stain may be transferred to the product, the surface smoothness of the paper may be impaired, or in severe cases, the paper may be cut, resulting in a problem that productivity is significantly reduced.

[0008] Therefore, the present invention is to disperse the filler and drug-containing deposits eluted from paper with a water-soluble polymer compound, and to disperse the ketene dimer sizing particles contained in the coating solution. Of the hot water sized papermaking surface sizing composition which is extremely excellent in heat and mechanical stability. It is an object of the present invention to provide a paper sizing method that can improve quality.

[0009]

Means for Solving the Problems The present inventors have conducted intensive studies to solve the above-mentioned problems, and as a result, as a surface sizing composition for papermaking in a warm water size system, a ketene dimer sizing agent and a water-soluble polymer were used. The present inventors have found that the use of the compound in combination with the compound at a certain ratio or less can reduce the stain on the papermaking apparatus, improve the operability, and improve the size performance, and have completed the present invention. Was.

That is, the present invention provides the following general formula (1)

[0011]

Embedded image

(Wherein R ₁ and R ₂ are an alkyl, alkenyl or aryl group having 8 to 24 carbon atoms). A ketene dimer sizing agent containing a ketene dimer (a)
And (a) / (b) = 90/10 to
The present invention relates to a hot water sized paper surface sizing composition containing 25/75 by weight and a surface sizing method using the same.

Next, the present invention will be described in detail. The ketene dimer constituting the present invention is a compound represented by the above general formula (1), and any known ketene dimer can be used. In the above general formula (1), R ₁ and R ₂ represent various carbon atoms of 8 to
24, preferably 12 to 22 identical or different hydrocarbon radicals. Examples of these hydrocarbon groups include octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl and other alkyl groups, octenyl, decenyl, dodecenyl, tetradecenyl, hexadecenyl,
Examples thereof include alkenyl groups such as octadecenyl and eicosenyl groups, and aryl groups such as octylphenyl, nonylphenyl, and dodecylphenyl. Of these, alkyl groups are preferable. Further, in terms of physicochemical constants, the melting point of the ketene dimer is preferably from 20 to 80 ° C. If the alkyl group composition is within this range, one kind may be used alone, or two or more kinds may be used in combination. Here, the melting point refers to a rising melting point and is a value measured by a capillary method. Further, other additives may be used in combination with the above ketene dimer, and examples thereof include paraffin oil, fatty acid esters, and aromatic esters.

In order to obtain the ketene dimer represented by the above general formula (1) in the present invention, for example, a fatty acid chloride obtained by reacting a fatty acid mixture as a raw material with phosphorus trichloride is subjected to a dehydrochlorination reaction. A known method performed in the presence of a tertiary amine catalyst may be applied.

The ketene dimer sizing agent of the present invention
(a) can be produced by a conventionally known method using the above ketene dimer. In other words, the
Dimer sizing agent (a) is a ketene dimer,
De, dispersants, which consist of water or the like, for example, a ketene dimer and the protective colloids or dispersing agent represented by the above general formula (1) was mixed with hot water in a solvent, a homomixer, high-pressure pumping It can be obtained by uniformly dispersing with various known emulsifiers such as a mold homogenizer and an ultrasonic emulsifier.

Further, known protective colloids and dispersants can be used. For example, cationic dispersants such as cationic starch, anionic dispersants such as lignin sulfonate and naphthalene sulfonate formaldehyde condensate, nonionic dispersants such as sugar ester, and cationic, anionic and amphoteric vinyl Synthetic polymer-based protective colloids such as polymer-based polymers.
These can be used alone or in combination of two or more.

The ketene dimer sizing agent (a) of the present invention thus obtained is used for both the internal size and the surface size. The surface sizing agent has a ketene dimer concentration in the sizing agent. 10-30% by weight, non-volatile content 15-25% by weight, dispersed particle size 10 microns or less, ζ-potential -30 ~ +
Preferably, the viscosity is 15 mV, the viscosity is 100 centipoise or less, and the pH is 6.5 or less.

Next, the water-soluble polymer compound of the present invention
(b) is one or more water-soluble polymer compounds selected from anionic polymer compounds, cationic polymer compounds, amphoteric polymer compounds and nonionic polymer compounds, and has a molecular weight of several thousand to several million Are preferred. In addition, this water
Ketene dimer sizing agent (a)
Polymer compounds used as protective colloids and dispersants
Things are not included.

Examples of the anionic polymer compound include a naphthalene sulfonate formaldehyde condensate, a polystyrene sulfonate, a poly (meth) acrylate, a salt of a copolymer of a vinyl compound and an anionic monomer, and a cellulose derivative. , Starch derivatives and the like. Examples of the vinyl monomer in the salt of the copolymer of the vinyl compound and the anionic monomer include (meth) acrylic acid ester, alkyl vinyl ether, (meth) acrylamide, and (meth) acrylamide.
Examples thereof include acrylonitrile, styrene, and olefins such as pentene, hexene, and heptene. Examples of the anionic monomer include monomers having a carboxylic acid group such as (meth) acrylic acid, fumaric acid, maleic acid, itaconic acid, and crotonic acid and salts thereof, vinylsulfonic acid, styrenesulfonic acid, and 2-acrylamide. Monomers having a sulfonic acid group such as -2-methylpropanesulfonic acid and salts thereof,
Alternatively, a phosphoric acid ester of hydroxyalkyl (meth) acrylate and a salt thereof can be mentioned. Furthermore,
Monomers or copolymers having a dicarboxylic acid group are ethyl alcohol, propyl alcohol, butyl alcohol,
It may be used after being partially esterified with a compound having a hydroxyl group such as ethylene glycol ethyl ether or ethylene glycol butyl ether. These monomers can be used alone or in combination of two or more.

The cationic polymer compound is a compound sharing a cationic group selected from tertiary amino groups or quaternary ammonium salts, and is glycidyltrimethylammonium chloride or 3-chloro-2-hydroxypropyltrimethylammonium. Cellulose derivative or starch derivative obtained by reacting
Cationic vinyl compounds such as vinylpyridinium chloride) and poly (N-vinyl-2,3-dimethylimidazolinium chloride), or cationic diallyl compounds, and a copolymer containing a cationic monomer and a vinyl compound. And salts of polymers. Examples of the vinyl monomer in the salt of the copolymer containing a cationic monomer and a vinyl compound include (meth) acrylic acid ester, alkyl vinyl ether, (meth) acrylamide, (meth) acrylonitrile, styrene, and pentene. , Hexene, heptene and the like. Examples of the cationic monomer include vinyl monomers having a tertiary amino group such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, or diethylaminopropyl (meth) acrylamide. Examples thereof include salts of inorganic or organic acids such as hydrochloric acid, sulfuric acid, nitric acid and acetic acid, and monomers containing a quaternary ammonium salt obtained by a vinyl monomer reaction containing a tertiary amino group.
Each of these monomers can be used alone or in combination of two or more.

The amphoteric polymer compound includes an anionic group selected from a carboxylic acid group, a sulfonic acid group and a phosphoric acid group, and a cationic group selected from a tertiary amino group or a quaternary ammonium salt. Examples of the compound to be shared include a salt of a copolymer containing an anionic monomer, a cationic monomer and a vinyl compound, and a salt of a copolymer containing a vinyl compound and an amphoteric monomer. Examples of the monomer in the salt of the copolymer containing an anionic monomer, a cationic monomer and a vinyl compound include (meth) acrylic acid esters,
Alkyl vinyl ether, (meth) acrylamide,
Examples thereof include (meth) acrylonitrile, styrene, and olefins such as pentene, hexene, and heptene.
Examples of anionic monomers include (meth) acrylic acid, fumaric acid, maleic acid, itaconic acid, monomers having a carboxylic acid group such as crotonic acid and salts thereof, vinylsulfonic acid,
Examples thereof include monomers having a sulfonic acid group such as styrenesulfonic acid and 2-acrylamido-2-methylpropanesulfonic acid and salts thereof, and phosphoric acid esters of hydroxyalkyl (meth) acrylate and salts thereof. Further, the monomer or copolymer having a dicarboxylic acid group may be used after being partially esterified with a compound having a hydroxyl group such as ethyl alcohol, propyl alcohol, butyl alcohol, ethylene glycol ethyl ether, and ethylene glycol butyl ether. Absent. Examples of the cationic monomer include vinyl monomers having a tertiary amino group such as dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, or diethylaminopropyl (meth) acrylamide. Salts of inorganic or organic acids such as hydrochloric acid, sulfuric acid, nitric acid or acetic acid,
Or a monomer containing a quaternary ammonium salt obtained by a vinyl monomer reaction containing a tertiary amino group. Each of these monomers can be used alone or in combination of two or more.

The vinyl monomer in the salt of the copolymer containing the vinyl compound and the amphoteric monomer includes (meth) acrylate, alkyl vinyl ether, (meth)
Examples thereof include acrylamide, (meth) acrylonitrile, styrene, and olefins such as pentene, hexene, and heptene. The amphoteric monomers include N-methacryloyloxyethyl-N, N-dimethylammonium-N-methylcarboxybetaine, N-methacryloylamidopropyl-N, N-dimethylammonium-N
-Methylcarboxybetaine, N-methacryloyloxyethyl-N, N-dimethylammonium-N-propylsulfobetaine, N-methacryloylamidopropyl-N, N-dimethylammonium-N-propylsulfobetaine and the like. These monomers can be used alone or in combination of two or more.

Examples of the nonionic polymer compound include cellulose derivatives such as polyvinyl alcohol, polyvinyl pyrrolidone, polyacrylamide, polymethacrylamide, polyethylene oxide, and hydroxyethyl cellulose.

Ketene dimer sizing agent in the present invention
Each component of (a) and the water-soluble polymer compound (b) is one or two
More than one species can be used in combination.

Ketene dimer sizing agent in the present invention
The paper-making surface sizing composition containing (a) and the water-soluble polymer compound (b) is useful for controlling sizing performance and roll contamination.
From the viewpoint of workability, the weight ratio of the total amount of the solid content of each component is
(a) / (b) = 90/10 to 25/75 .

Further, the concentration of the sizing composition in the surface sizing solution is preferably 2% by weight or less, and if added more than this, there is no significant difference between paper and paperboard which require oxidized starch, and the paper paper originally required Quality cannot be obtained.

In carrying out the surface sizing method for papermaking of the present invention, there is no particular limitation, and the ketene dimer sizing agent (a) and the water-soluble polymer compound (b) are mixed with paper or paperboard. Any conventionally known surface sizing method in which coating or impregnation is performed after the paper layer is formed in the manufacturing process can be adopted. More specifically, a size press, a size tab, a sizing agent is applied to the surface of the paper by a surface coating liquid applied by a gate roll coater, a calender, or the like at 0.005 to 5 g / m ² (solid content), preferably 0.01 to 1 g / m ^2. It may be added so that ^{2 is} applied.

Ketene dimer sizing agent used in the present invention
The method and order of adding (a) and the water-soluble polymer compound (b) are not limited, but the ketene dimer sizing agent may be added first, and then the water-soluble polymer compound may be added in this order. And vice versa. Further, these may be added at the same time, or a mixed solution obtained by mixing them may be added. The place of addition is not limited as long as it is a place in the papermaking process, but preferably the ketene dimer sizing agent (a) and the water-soluble polymer compound (b) are placed in a coating liquid circulation line such as a size press. It is desirable that they be added and sufficiently dispersed.

It is preferable that the application amount of the ketene dimer sizing agent (a) and the water-soluble polymer compound (b) be adjusted according to the degree of sizing required for the target paper. When the surface sizing method for papermaking of the present invention is carried out, a surface treating agent such as a dye and an additive such as an antifoaming agent may be mixed and used in the same coating liquid.

As the base paper to which the surface sizing method for papermaking of the present invention is applied, any of various types of paper such as gravure base paper and paperboard, which do not require the application of surface paper strength from oxidized starch or the like usually applied at the time of surface coating, etc. Can also be used.

[0031]

EXAMPLES Hereinafter, the present invention will be described specifically, but the present invention is not limited to these examples. Parts in the following examples are based on weight unless otherwise specified.

<Preparation of Ketene Dimer Sizing Agent>
A solution of ketene dimer (64.0% of stearic acid, 30.1% of palmitic acid, 4.3% of myristic acid, etc.) in a solution of cationic starch and gelatinized condensate of naphthalenesulfonate gelatinized at 1 ° C for 1 hour The mixture was melted and mixed at 70 ° C, emulsified using a high-pressure discharge homogenizer at a pressure (gauge pressure) of 300 kg / cm ² , cooled and cooled to obtain a ketene dimer sizing agent (S- 1) was obtained. The obtained ketene dimer sizing agent (S-1)
Non-volatile content 20.5%, HORIBA centrifugal automatic particle size distribution analyzer CA
Average particle size measured with PA-500 is 0.69μm, UK RANKBROT
The ζ-potential was −4.2 mV as measured by a microscopy electrophoretic colloid particle zeta potential measuring device manufactured by HERS, and the Brookfield viscosity was 4.8 centipoise and the pH was 4.3 at 25 ° C. and 60 revolutions per minute.

<Preparation of Surface Sizing Agent Composition for Paper Making> Examples 1 to 14 The prepared ketene dimer sizing agent (S-1) was prepared using the water-soluble polymer compounds (S-2 to S-) shown in Table 1. 13) was added by changing the kind and the mixing ratio to obtain a surface sizing composition for papermaking. Comparative Examples 1 to 5 The prepared ketene dimer sizing agent (S-1) and each water-soluble polymer compound were used alone as a surface sizing composition for papermaking.

[0034]

[Table 1]

Note)-The concentration of S-1 to S-13 is adjusted to 16.5%, and the numerical values represent the actual weight parts. -S-2 uses Kao's poise 535-S-3 uses BASF's Sokaran CP-5-S-4 uses Toyo Soda Kogyo's PS-50-S-5 uses Kao's synthetic product-S- 6 is Kao synthetic product ・ S-7 uses Union Carbide polymer JR-400 ・ S-8 is Kao synthetic product ・ S-9 is Kao synthetic product ・ S-10 is Kao synthetic product ・ S For -11, use Shin-Etsu Chemical's PVA C-17. For S-12, use Aldrich one with a molecular weight of 24,000. For S-13, use Cellosize QP-300, manufactured by Union Carbide.
use.

<Comparison of Paper Size Performance> The surface sizing composition for papermaking shown in Table 1 was adjusted to a predetermined concentration with 10 ° dH hard water to prepare a coating solution. Using this coating liquid, apply to a neutral paper-made ordinary weak paper with a lab size press machine,
The degree of steel sizing of the paper was measured. Table 2 shows the obtained results. Each papermaking condition, sizing condition,
The measurement conditions of the sizing test are shown below.

(1) Base paper Pulp: LBKP (Canadian Standard Freeness 400ml) Filler: Light calcium carbonate (Tamapearl 121, manufactured by Okutama Kogyo), added so that calcium carbonate in paper becomes 12% Fixing agent: cationization Starch (CATO 302, manufactured by Oji National), solid content 0.5% based on pulp Sizing agent: Ketene dimer sizing agent (Sirene S9
4, Kao), 0.05% solids based on pulp weight Retention enhancer: Cationic polyacrylamide polymer
(Percoll 47, manufactured by Kyowa Sangyo Co., Ltd.), solid content 0.02% based on pulp weight Fixing pH: 8.0 Order of addition: Pulp-filler-fixing agent-sizing agent-yield improver Papermaking: Tappy square hand paper machine Press: 3.5 kgW / cm ² × 2 minutes Drying: Rotary dryer, 100 ° C./40 seconds Weighing: 70 g / m ² (2) Coating Surface sizing liquid composition A: Surface sizing composition for papermaking; 0.105% 10 ° dH hard water; 99.895% Surface sizing composition B: Surface sizing composition for papermaking; 0.525% 10 ° dH hard water; 99.475% (3) Size press Press speed: 100 m / min Nip pressure: 10 kg / cm Coating temperature: 50 ° C (4 ) Drying conditions Drying was performed at 105 ° C for 40 seconds using a rotary dryer. (5) Sizing test: Sekihid sizing test (JIS P-8122) Fold the four sides of the test paper upward to form a boat, 2% NH ₄ SCN
At the same time as floating on the aqueous solution, drop a drop of 1% FeCl ₃ aqueous solution from above onto the test paper, and the time until both aqueous solutions penetrate and touch the paper and three red spots of iron thiocyanate appear (seconds)
Was measured.

Table 2 shows the sizing degree of the paper coated under the above conditions. The higher the numerical value, the better.

[0039]

[Table 2]

<Mechanical Stability Test of Sizing Composition in Addition of Filler> A size liquid obtained by mixing and preparing a surface sizing composition for papermaking shown in Table 1 and a filler was subjected to a Malon mechanical stability tester. The mechanical stability was investigated. Table 3 shows the results. In addition, it shows that the stability of a sizing liquid is so bad that the amount of aggregates is large, and roll lees winding etc. are easily generated. Other conditions are shown below.

(1) Malon mechanical stability tester Machine No. 5459 manufactured by Rigaku Kogyo Co., Ltd. (2) Size liquid Treatment amount: 50 g Mixing ratio: surface sizing agent for papermaking / filler (CaCO ₃ ) /water=1.9
/0.1/98.0% (3) Test conditions Load: 10kgW Test temperature: 50 ° C Processing time: 10 minutes Rotation speed: 1000rpm (4) How to determine the amount of aggregates The size liquid treated under the above test conditions is passed through a 325 mesh wire mesh. The mixture was filtered, and the residue was dried and weighed. Aggregate weight was determined by the following equation.

[0042]

(Equation 1)

[0043]

[Table 3]

<Roll dirt simulation test> Table 1
Table 4 shows the results obtained by testing the size liquid obtained by mixing and preparing the papermaking surface sizing composition and the filler shown in the above with a roll dirt simulator. In addition, as for the soiling property of the roll, the solid content weight was determined after scraping off the foreign matter adhering to the roll and drying. Also, the larger the amount of deposits, the worse the roll stainability. Other test conditions are shown below.

(1) Roll dirt simulator device Chino Co., Ltd. Roll material: NBR, SUS Rotation speed: 150 rpm (2) Size liquid treatment amount: 2000 ml Mixing ratio: paper sizing agent / filler (CaCO ₃ ) / water = 1.
9 / 0.1 / 98.0% Temperature: 50 ° C Processing time: 2 hours

[0046]

[Table 4]

Continuation of the front page (72) Inventor Koji Ikeda 1130 Nishihama, Wakayama City, Wakayama Prefecture (72) Inventor Hirotaka Takahashi 1031-10, Sonobe, Wakayama City, Wakayama Prefecture (56) References A) JP-A-2-33392 (JP, A) JP-A-1-280096 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) D21H 19/24

Claims (3)

(57) [Claims] [Claim 1] The following general formula (1) (Wherein, R ₁ and R ₂ are an alkyl group, an alkenyl group or an aryl group having 8 to 24 carbon atoms), and a ketene dimer sizing agent (a) containing a ketene dimer represented by the following formula: (A) / (b) = 90 / 10-25 / 75
A hot water size surface sizing composition for papermaking , containing at a ratio . 2. The water-soluble polymer compound (b) is one or more water-soluble polymer compounds selected from an anionic polymer compound, a cationic polymer compound, an amphoteric polymer compound and a nonionic polymer compound. claim 1 heated sizes based papermaking surface sizing composition according is. 3. A paper-making surface sizing method, wherein the hot-water-size papermaking sizing composition according to claim 1 or 2 is used for paper or paperboard which does not require application of surface paper strength by applying oxidized starch. .