JP2012224949A - Method for producing paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for producing paper that satisfies steep rise in size effect while suppressing deterioration in friction coefficient of the paper.SOLUTION: There is provided a method for producing paper in which a copolymer (A) comprising a diallylamine-based monomer (a1) represented by a general formula (1) is coated in a solid coated amount of 0.005-1 g/m, an alkyl and/or alkenyl ketene dimer (B) is coated in a solid coated amount of 0.005-0.15 g/m, and a water soluble polymer (C) is coated in a solid coated amount of 0.001-10 g/m, on a surface. (In the formula, Rand Rrepresent a hydrogen or a methyl group, Rrepresents a hydrogen or a 1-4C alkyl group.)

Description

The present invention relates to a paper manufacturing method. In particular, the present invention relates to a paper manufacturing method suitably used for liners and newspapers.

Conventionally, when producing a fiber product such as paper or wood fiber, a sizing agent has been used to impart water resistance, ink resistance, bleed resistance, and the like to the product. Examples of such a sizing agent include rosin-based sizing agents represented by rosin having a carboxyl group or reinforced rosin (maleinized rosin). However, rosin-based sizing agents themselves can be fixed on cellulose fibers. Since it is difficult, papermaking has been performed in an acidic range of pH 4.5 to 6.5 using a sulfuric acid band in combination. For this reason, there are problems such as large deterioration of quality of the paper over time, complicated wastewater treatment, corrosion of papermaking equipment, etc., and generation of carbon dioxide gas due to decomposition when using calcium carbonate which is an inexpensive filler. there were.

In order to solve these problems, a sizing method in the neutral region of pH 6.5 to 8.0 has been attracting attention in recent years. Use of inexpensive calcium carbonate as a filler, use of waste paper or waste paper containing calcium carbonate, papermaking The system has become closed. Neutral sizing agents include ketene dimer sizing agents, substituted cyclic dicarboxylic acid anhydride sizing agents, and copolymers of cationic unsaturated monomers and hydrophobic unsaturated monomers. Ketene dimer-based sizing agents are widely used because of the above simplicity and high size effect due to the addition of a small amount.

Ketene dimer-based sizing agents can be used in a wide range of papermaking pH ranges, and have a characteristic of showing a high sizing effect when added in a small amount. However, ketene dimer-based sizing agents are used to impart a sizing effect to paper. As a method, there are generally a method in which a sizing agent is internally added to a pulp slurry, and a method in which a sizing agent is applied to the surface of paper after forming pulp into a sheet.

By the way, conventionally, among ketene dimer sizing agents, alkyl ketene dimer (AKD) is often used as a sizing agent because it has a characteristic of showing a high size effect. However, when AKD is used as a sizing agent, the method of internally adding AKD to the pulp slurry (method of internal addition) has a problem that the papermaking machine is soiled by the hydrolyzed AKD. Also, the yield to pulp is not perfect and is inefficient in developing the size effect. On the other hand, all the methods for applying AKD to the surface of paper yield yield on paper, so that a size effect can be efficiently imparted. However, the method of applying AKD to the surface of the paper tends to reduce the coefficient of friction of the paper, causing cardboard collapse when transporting cardboard, and causing paper slippage when printing on a rotary press for printing paper. Since the paper is wrinkled, there is a problem that the use of the paper is limited.

Further, when AKD is used, it takes time until the size effect is manifested, not limited to the method of internal addition and the method of coating on the surface, and there is a problem in the so-called “rise of size effect”. The poor rise of the size effect is complicated because it is necessary to perform a heat treatment in order to measure the state of the rise of the size effect in paper quality control. In addition, the so-called on-machine coated paper, which is coated with a pigment and a binder after the paper is made, does not exhibit a size effect, and the coating solution penetrates into the paper and the uniformity of the coated paper is impaired. There was a problem. On the other hand, in order to solve the rise of the size effect, when trying to cope by increasing the amount of added AKD, since AKD is a wax component, the coefficient of friction of the paper decreases and the paper becomes slippery. cause.

In order to solve such a problem, a method has been proposed in which a ketene dimer-based sizing agent is used as a dispersant of a polymer of a specific cationic vinyl monomer and a nonionic compound. (Patent Document 1) However, although the rise is improved by this method, the decrease in the friction coefficient of paper when applied to the surface of the paper is not sufficient.

For this, a surface sizing agent that is used in combination with a water-soluble polymer compound after controlling the zeta potential within a specific range has been proposed. (See Patent Document 2). According to this method, although the reduction of the friction coefficient can be improved, the rise of the size effect is insufficient.

As described above, there is still room for improvement in the paper manufacturing method that satisfies both the rise of the size effect while suppressing the decrease in the friction coefficient of the paper.

JP-A-6-299494 JP 2003-221895 A

SUMMARY OF THE INVENTION An object of the present invention is to provide a paper manufacturing method that satisfies a rapid rise in size effect while suppressing a decrease in paper friction coefficient.

As a result of intensive investigations to solve the above-mentioned problems, the present inventors have applied a copolymer containing a specific diallylamine monomer, an alkyl and / or alkenyl ketene dimer, and a coating amount of a water-soluble polymer. The present invention has been completed by finding that the above-mentioned problems can be solved by adopting a production method in which these are applied to the surface of paper with the above-mentioned in a specific range.

That is, the present invention 1 includes a copolymer (A) containing a diallylamine monomer (a1) represented by the general formula (1) having a solid content coating amount of 0.005 to 1 g / m ² , a solid content. coating amount is 0.005~0.15g / ^{m 2} alkyl and / or alkenyl ketene dimer (B), and water-soluble polymer solid coating amount is 0.001 to 10 g / ^{m 2} ( C) is a method for producing a paper to be coated on the surface.
(In the formula, R ¹ and R ² represent hydrogen or a methyl group, and R ³ represents hydrogen or an alkyl group having 1 to 4 carbon atoms.)

The present invention 2 is the paper manufacturing method of the present invention 1, wherein the copolymer (A) contains 1 to 50 mol% of the diallylamine monomer (a1) represented by the general formula (1), (meth) This is a method for producing paper containing 50 to 99 mol% of acrylamide (a2).

The present invention 3 is the paper manufacturing method of the first or second invention, wherein the water-soluble polymer (C) is starch and / or polyacrylamides.

The paper manufacturing method of the present invention can provide a paper that satisfies the rapid rise of the size effect while suppressing a decrease in the friction coefficient of the paper. It can be used for liners and newspapers where high coefficient of friction is regarded as important.

In the method for producing paper of the present invention, the diallylamine monomer (a1) represented by the general formula (1) having a solid content coating amount of 0.005 to 1 g / m ² (hereinafter referred to as “component (a1)”). Copolymer (A) (hereinafter referred to as component (A)), alkyl and / or alkenyl ketene dimer (B) (hereinafter referred to as (A) having a solid content coating amount of 0.005 to 0.15 g / m ^2. B) component) and a water-soluble polymer (C) (hereinafter referred to as component (C)) having a solid content coating amount of 0.001 to 10 g / m ² is applied to the surface.

(Wherein R ¹ and R ² represent hydrogen or a methyl group, and R ³ represents hydrogen or an alkyl group having 1 to 4 carbon atoms)

The component (A) includes at least the component (a1) represented by the general formula (1). The component (a1) is not particularly limited as long as it is represented by the general formula (1), and a known component can be used. Specific examples include diallylamine, diallylmethylamine, diallylethylamine, diallylbutylamine, and dimethallylamine. The diallylamine may be a salt. Examples of the diallylamine salts include inorganic acids such as hydrochloric acid, nitric acid, sulfuric acid, and phosphoric acid, and organic acid salts such as formic acid, acetic acid, and propionic acid. In addition, these may be used individually by 1 type, or 2 or more types may be mixed and used for them. In addition, (A) component is obtained by polymerizing the monomer containing at least (a1) component. The polymerization method is not particularly limited, and a known radical polymerization method can be employed.

As the component (a2), acrylamide and methacrylamide can be used.

The component (A) is 1 to 50 mol% of the component (a1) represented by the general formula (1) and 50 to 99 mol% of (meth) acrylamide (a2) (hereinafter referred to as component (a2)). It is preferable from the viewpoint that the rise of the size effect is good, and the rise of the size effect is further good when the component (a1) is 2 to 30 mol% and the component (a2) is 70 to 98 mol%. It is preferable in that

The component (A) further controls the polymer structure of the component (A) by containing an unsaturated monomer (a3) (hereinafter referred to as the component (a3)) other than the components (a1) and (a2). Therefore, it is preferable in that it shows a better size effect. When the component (A) contains 1 to 50 mol% of the component (a1) and 50 to 99 mol% of the component (a2), the size effect is that 0.01 to 5 mol% of the component (a3) is contained. This is preferable in that a good size effect is exhibited without inhibiting the rise.

The component (a3) is an unsaturated monomer copolymerizable with the monomer component constituting the component (A).
Examples of the component (a3) include an anionic monomer, a cationic monomer, and a nonionic monomer. Moreover, you may use together a well-known crosslinkable monomer in the range which does not impair the objective of this invention.

The anionic monomer is not particularly limited as long as it is a monomer having an anionic functional group and one radical polymerizable functional group, and known ones can be used. Examples of the anionic functional group include a carboxyl group, a sulfo group (—SO ₃ H), and a phosphate group (—H ₂ PO ₄ ). Specifically, as the carboxyl group-containing monomer, α, β-unsaturated monocarboxylic acid such as (meth) acrylic acid, crotonic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, muconic acid, Examples include α, β-unsaturated dicarboxylic acids such as citraconic acid. Examples of the sulfo group (—SO ₃ H) -containing monomer include vinyl sulfonic acid, styrene sulfonic acid, allyl sulfonic acid, and 2-acrylamido-2-methylpropane sulfonic acid. Examples of the phosphoric acid group (—H ₂ PO ₄ ) -containing monomer) include 2- (meth) acryloyloxyethyl acid phosphate, 3- (meth) acryloyloxypropyl acid phosphate, and the like. In addition, these anionic functional groups may be salts such as alkali metal salts such as sodium salts and potassium salts, and ammonium salts with ammonia and amines. These monomers may be used alone or in combination of two or more. Among these, α, β-unsaturated monocarboxylic acid, α, β-unsaturated dicarboxylic acid and salts thereof are preferable from the viewpoint of greatly improving the size effect.

The cationic monomer is not particularly limited as long as it is a monomer having a cationic functional group and one radical polymerizable functional group other than the component (a1). Things can be used. Examples of the cationic functional group include a primary amino group, a secondary amino group, and a tertiary amino group. Specific examples thereof include dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, dimethylaminopropyl (meth) acrylate, diethylaminopropyl (meth) acrylate, dimethylaminopropyl (meth) acrylamide, and diethylaminopropyl (meth). Examples include acrylamide and allylamine. In addition, these cationic functional groups may be salts of inorganic acids or organic acids such as hydrochloric acid, sulfuric acid, formic acid, and acetic acid. Further, a part or all of the tertiary amino group may be converted to a quaternary ammonium ion with a quaternizing agent. Examples of the quaternizing agent include alkyl halides such as methyl chloride and methyl bromide, arylalkyl halides such as benzyl chloride and benzyl bromide, dimethyl sulfate, diethyl sulfate, epichlorohydrin, 3-chloro-2-hydroxypropyltrimethyl. Ammonium chloride, glycidyl trialkyl ammonium chloride, styrene oxide, propylene oxide and the like can be mentioned. These monomers may be used alone or in combination of two or more.

As said nonionic monomer, if it is a monomer which has one radical polymerizable functional group, it will not specifically limit, A well-known thing can be used. Specifically, for example, an ester of an alcohol such as an alcohol having 1 to 8 carbon atoms and acrylic acid or methacrylic acid, (meth) acrylic acid hydroxyalkyl ester, (meth) acrylonitrile, styrene, a styrene derivative, vinyl acetate, Examples include vinyl propionate and methyl vinyl ether. These monomers may be used alone or in combination of two or more.

The crosslinkable monomer is not particularly limited as long as it has at least two radical polymerizable functional groups, and a known monomer can be used. Specifically, for example, di (meth) acrylates such as ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, propylene glycol di (meth) acrylate, glycerin di ( (Meth) acrylate, trimethylolpropane / ethylene oxide adduct triacrylate, methylenebis (meth) acrylamide, ethylenebis (meth) acrylamide, hexamethylenebis (meth) acrylamide, N, N'-bisacrylamideacetic acid, N, N'- Bis (meth) acrylamides such as methyl bisacrylamide, N, N-benzylidenebisacrylamide, divinyl esters such as divinyl adipate and divinyl sebacate, epoxy acrylate , Urethane acrylates, allyl (meth) acrylate, diallyl phthalate, diallyl malate, diallyl succinate, diallylacrylamide, divinylbenzene, diisopropylbenzene, N, N-diallylmethacrylamide, N-methylolacrylamide, diallyldimethylammonium, diallyl Bifunctional monomers such as chlorendate, glycidyl (meth) acrylate, 1,3,5-triacryloylhexahydro-S-triazine, triallyl isocyanurate, N, N-diallylacrylamide, triallylamine, triallyltri Trifunctional monomers such as melitrate, tetramethylol methane tetraacrylate, tetraallyl pyromellitate, N, N, N ′, N′-tetraallyl-1,4-diaminobutane, tetraary Amine salts, tetrafunctional monomers such as tetraallyloxyethane and the like.

As the component (B), an alkyl ketene dimer and / or an alkenyl ketene dimer can be used. Specifically, for example, the general formula (2):
(In the formula, R ⁴ and R ⁵ are a saturated hydrocarbon group having 6 to 30 carbon atoms or an unsaturated hydrocarbon group having 6 to 30 carbon atoms, and R ⁴ and R ⁵ are the same or different. It is also possible to use a compound represented by:

In the general formula (2), the hydrocarbon group represented by R ⁴ or R ⁵ is, for example, an alkyl group such as hexyl, heptyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, octadecyl, eicosyl, octenyl, decenyl, dodecenyl, Examples thereof include alkenyl groups such as tetradecenyl, hexadecenyl, octadecenyl and eicosenyl, substituted phenyl groups such as octylphenyl, nonylphenyl and dodecylphenyl, substituted cycloalkyl groups such as nonylcyclohexyl, and aralkyl groups such as phenylethyl. R ⁴ and R ⁵ are not limited to linear hydrocarbons, and may be branched or cyclic. Examples include octadecyl ketene dimer, hexadecyl ketene dimer, tetradecyl ketene dimer, and dodecyl ketene dimer. The ketene dimer may be a dimerized mixture of different fatty acids.

The component (B) may be emulsified by a known method and used as an emulsion. In emulsification, for example, cationized starch, sodium lignin sulfonate, naphthalene sulfonate formalin condensate, and the like can be used as an emulsifying dispersant. Although the usage-amount of an emulsifying dispersant is not specifically limited, Usually, about 5-100 weight part is used by solid content with respect to 100 weight part of (B) component which is an emulsification object. The emulsification method is not particularly limited and may be a known method. For example, the emulsification method can be obtained by dispersing component (B) in the presence of various known surfactants. Examples of the method used for dispersion include forced emulsification, inversion emulsification, and solvent emulsification, but a forced emulsification method using a high-pressure homogenizer is preferable.

The component (C) is a water-soluble polymer other than the component (A). As component (C), starch, various modified starches, carboxymethylcellulose, polyamide polyamine-epichlorohydrin resin, polyacrylamides, alkali salt of styrene-maleic acid copolymer, alkali salt of styrene- (meth) acrylic acid copolymer , Olefin-maleic acid alkali salt, acrylic ester- (meth) acrylic acid alkali salt, and the like. Starch and / or polyacrylamides are preferred in that the size effect can be further improved.

Examples of the polyacrylamide include a copolymer of acrylamide and the anionic monomer, cationic monomer, and nonionic monomer, and acrylamide and acrylamide in the presence of a polymerization initiator such as ammonium persulfate. It can be produced by polymerizing an anionic monomer, a cationic monomer, and a nonionic monomer.

The starch is not particularly limited, and gelatinized liquids such as oxidized starch, enzyme-modified starch, and APS (ammonium persulfate) -modified starch can be used.

The solid content coating amounts of the component (A), the component (B), and the component (C) are 0.005 to 1 g / m ² , 0.005 to 0.15 g / m ² , and 0.001 to 0.001, respectively. 10 g / m ² . By setting the coating amount within this range, it is possible to satisfy the rise in size effect while suppressing a decrease in the friction coefficient of the paper. When component (A) is less than 0.005 g / ^{m 2,} it worsens the rising of sizing effect, exceeds 1 g / ^{m 2,} (A) component size effect is lowered due to a high hydrophilicity. (B) component is less than 0.005 g / ^{m 2,} the lower the size effect, exceeds 0.15 g / ^{m 2,} the friction coefficient of the paper decreases. When the component (C) is less than 0.001 g / m ² , the size effect is lowered due to a decrease in the dispersibility of the component (B), and when it exceeds 10 g / m ² , the drying load of the dryer after coating is reduced. Becomes larger. More preferably, the solid content coating amounts of the components (A), (B), and (C) are 0.010 to 0.500 g / m ² , 0.010 to 0.100 g / m ² , and 0. 010 to 3.000 g / m ² .

The paper used in the production of the paper of the present invention is not particularly limited, and an uncoated paper including a paperboard made of wood cellulose fiber as a raw material can be used without any particular limitation. Paper is obtained from pulp for papermaking, and as pulp for papermaking, chemical pulp such as LBKP (L-bleached kraft pulp), NBKP (N-bleached kraft pulp), GP (ground wood pulp), TMP Examples thereof include mechanical pulp such as (thermomechanical pulp), waste paper pulp and the like. In particular, when paper containing waste paper pulp uses a sizing agent containing the above component (B), the size effect has conventionally been difficult to be exhibited, but according to the paper manufacturing method of the present invention, it has waste paper pulp. The present invention is effective because a good sizing effect is exerted also on paper. Also, there are no particular limitations on various internal additives such as fillers, sizing agents, and paper strength enhancers that are internally added to the paper.

The paper manufacturing method of the present invention is characterized in that the component (A), the component (B), and the component (C) are coated on the surface of paper that has been made without being added to the paper. It is. By applying to the surface, a size effect can be efficiently imparted without losing chemicals. Examples of the coating method include an impregnation method, a bar coater method, a calendar method, a spray method, a method such as a two-roll size press, and a film transfer method such as a gate roll size press and a shim size press. The order of surface coating of each component is not particularly limited, and the components may be mixed and performed simultaneously, or may be performed for each component, and the mixture of component (A) and component (B) is the surface. (C) component may be surface-coated after coating, and the mixture of (B) component and (C) component may be surface-coated after surface-coating (A) component.

Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to these examples. In the examples, “%” and “part” mean “% by weight” and “part by weight” unless otherwise specified.

(Production of copolymer of diallylamine monomer and acrylamide)
Synthesis example 1
A reactor equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel was charged with 1330.0 parts of ion exchange water and 7.8 parts of diallylamine (0.08 mol), and then 35% diluted. The pH was adjusted to 7 with sulfuric acid. After removing oxygen in the reaction system through nitrogen gas, the mixture was heated to 70 ° C. and 3.5 parts of ion-exchanged water ammonium persulfate was added. Next, 549.4 parts (3.92 mol) of a 50% aqueous acrylamide solution was added at 70 ° C. over 2 hours, and the mixture was kept at 70 ° C. for 2 hours. After completion of the polymerization, ion-exchanged water was added to obtain a copolymer (A) of a diallylamine monomer and acrylamide having a nonvolatile content of 15.5%, pH 3.7, and viscosity (25 ° C.) of 3600 mPa · s.

Synthesis Examples 2-12
In Synthesis Example 1, a copolymer (A) was obtained in the same manner as in Synthesis Example 1, except that the types and use ratios of a1, a2, and other unsaturated monomers were changed to those shown in Table 1. . As other unsaturated monomers, when acrylic acid and itaconic acid are used in combination, a 10% aqueous sodium hydroxide solution is added to 50% acrylamide aqueous solution and then adjusted to pH 7, and N, N-dimethyl is added. When aminoethyl methacrylate was used in combination, 35% dilute sulfuric acid necessary for neutralization was added to a 50% acrylamide aqueous solution, N, N-dimethylaminoethyl methacrylate was added, and synthesis was performed at pH 7. The results are shown in Table 1.

DAA: diallylamine, AM: acrylamide, DAMA: diallylmethylamine, AA: acrylic acid, ITA: itaconic acid, DM: N, N dimethylaminoethyl methacrylate, AN: acrylonitrile, MBAA: methylenebisamylylamide

(Preparation of sizing agent containing alkyl and / or alkenyl ketene dimer)
AKD-1 synthesis example 80 parts of alkyl ketene dimer (from a mixture of 50% stearic acid and 50% palmitic acid) and 10% cationized starch paste (nitrogen content) previously gelatinized at 90 ° C. for 1 hour 2. 0.50 to 0.60%, 185 parts of oxidized starch cation-modified with glycidyltrimethylammonium chloride), 40% aqueous solution of anionic dispersant (naphthalenesulfonic acid formalin condensate, manufactured by Kao Corporation) 75 parts and 131.25 parts of water were charged, heated to 70 to 80 ° C., predispersed with a homomixer (manufactured by Tokushu Kika Kogyo Co., Ltd.), and then subjected to 250 kg / cm ² at the same temperature. The mixture was dispersed twice by passing through a high-pressure homogenizer (manufactured by APV. GAULIN). Immediately cooled to 25 ° C., water for concentration adjustment was further added, and the non-volatile content was 20.5%, the viscosity was 12.5 mPa · s (25 ° C.), the pH was 3.5 (25 ° C.), and the average particle size was 0.7 μm. A sizing agent (B) AKD-1 containing an alkyl ketene dimer was obtained.

AKD-2 Synthesis Example In the AKD-1 synthesis example, the type of ketene dimer was changed as shown in Table 2, and a sizing agent containing an alkyl ketene dimer and an alkenyl ketene dimer (B) AKD by the same method as in the AKD-1 synthesis example -2 was obtained. The results are shown in Table 2.

(Adjustment of water-soluble polymer)
Preparation Example of Water-Soluble Polymer-1 (Starch) After charging 900 parts of ion-exchanged water and oxidized starch (trade name: Oji Ace A) manufactured by a reactor equipped with a stirrer, thermometer, and reflux condenser. The mixture was heated to 80 ° C. and kept for 2 hours to obtain a water-soluble polymer-1 having a nonvolatile content of 10.0%, a pH of 6.9, and a viscosity (25 ° C.) of 55 mPa · s.

Synthesis example of water-soluble polymer-2 (polyacrylamides) In a reactor equipped with a stirrer, thermometer, reflux condenser, nitrogen gas inlet tube and dropping funnel, 1000 parts of ion-exchanged water, 350 parts of acrylamide as polyacrylamides After charging 20 parts of itaconic acid, 5 parts of acrylic acid and 3 parts of sodium methallyl sulfonate, the mixture was heated to 40 ° C., and 1 part of ammonium persulfate and 0.2 parts of sodium pyrosulfite were added at 40 ° C. After the temperature rose to 80 ° C. by polymerization heat, the temperature was kept for 3 hours. Subsequently, 48% sodium hydroxide for adjusting pH and water for adjusting concentration were added to obtain water-soluble polymer-2 having a non-volatile content of 20%, pH 6.0, and viscosity (25 ° C.) of 1600 mPa · s.

(Example)
By adding a sizing agent (B) containing a copolymer (A) of a diallylamine monomer and acrylamide, an alkyl ketene dimer, and a water-soluble polymer (C) to water (each blending ratio is shown in Table 3). As described above, a coating solution was prepared. Next, a coating amount of 15 g / m ² is applied to a weak acid liner base paper made from corrugated waste paper pulp having a cobb size of 178 g / m ² and a basis weight of 180 g / m ² using a bar coater. So that it was coated. Then, it dried at 80 degreeC for 60 second using the rotary drum dryer, and obtained the test paper. The Cobb sizing degree immediately after drying of the obtained test paper was measured. Moreover, the Cobb sizing degree and the slip angle were measured after conditioning for 24 hours in a constant temperature and humidity (23 ° C., 50% relative humidity) environment. Table 3 shows the coating amount and the result of each chemical.

(performance test)
(Water absorption test [Cobb method])
Cobb sizing degree (g / m ² ) was measured according to JIS P-8140. The contact time with water is 2 minutes, and the smaller the value, the better the sizing degree.
(Slip angle [tilt method])
The slip angle (°) was measured according to the tilt method of JIS P-8147. The smaller the sliding angle, the easier it is to slip.
(Average particle size)
The average particle diameter (μm) was measured with a particle size measuring apparatus LASER DIFFRATION PARTICIZE SIZE ANALYZER SALD-2000J (manufactured by Shimadzu Corporation) using a laser diffraction / scattering method.
(PH)
Using a glass electrode pH meter (manufactured by Horiba, Ltd.), the temperature of the coating solution was adjusted to 40 ° C., and the pH was measured.
(viscosity)
The sample temperature was 25 ° C., and the viscosity (mPa · s) was measured using a Brookfield viscometer.

Claims (3)

A copolymer (A) containing a diallylamine monomer (a1) represented by the general formula (1) having a solid content coating amount of 0.005 to 1 g / m ² and a solid content coating amount of 0.005. Alkyl and / or alkenyl ketene dimer (B) which is ˜0.15 g / m ² and water-soluble polymer (C) whose solid content coating amount is 0.001 to 10 g / m ² on the paper surface Manufacturing method of paper to be coated.
(Wherein R ¹ and R ² represent hydrogen or a methyl group, and R ³ represents hydrogen or an alkyl group having 1 to 4 carbon atoms) The copolymer (A) contains 1 to 50 mol% of the diallylamine monomer (a1) represented by the general formula (1) and 50 to 99 mol% of (meth) acrylamide (a2). The paper manufacturing method according to claim 1. The paper manufacturing method according to claim 1 or 2, wherein the water-soluble polymer (C) is starch and / or polyacrylamides.