JP2003155690A - Rosin-based emulsion composition, method for sizing paper and paper - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sizing agent that exhibits an excellent sizing effect, even when paper is made with a high speed paper-making machine at pH 4 to 8 under a relatively mild drying condition, and has excellent mechanical stability and storage stability. SOLUTION: This rosin-based emulsion composition comprises (A) a rosin- based substance and (B) a dispersant comprising a copolymer obtained by copolymerizing a styrenic monomer, a (meth)acrylate-based monomer, a (meth) acrylamide-based monomer, and (meth)acrylic acid.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a rosin emulsion composition, a sizing method and sized paper,
More specifically, a rosin containing a rosin-based substance and a dispersant containing a styrene-based monomer, a (meth) acrylic acid ester-based monomer, a (meth) acrylamide-based monomer, and (meth) acrylic acid as constituent components of a copolymer. A system emulsion composition, which exhibits an excellent size effect in a papermaking system from pH 4 to pH 8, especially when the papermaking speed is high and the drying conditions are mild, that is, the amount of heat applied to the wet paper is relatively low. It has an excellent size effect even for paper produced under the drying conditions of a paper machine, for example, a paper machine having a Yankee dryer or a paper machine for ultra-high-speed newsprint, and has a mechanical and storage stability of its own. Regarding superior sizing agents.

[0002]

2. Description of the Related Art In the papermaking industry, papermaking machines are operated at higher speeds to improve productivity, and as a result, they are often dried rapidly under relatively low temperature conditions, and conventional rosin sizing agents are not sufficient for papermaking. There is a tendency that size is not given.
For example, JP-A-2-53555 and JP-A-7-2290.
The rosin sizing agent disclosed in Japanese Patent No. 87 uses a styrene- (meth) acrylic acid copolymer as a dispersant. The rosin sizing agent disclosed in JP-A-7-258994 is used as a dispersant in styrene-
A copolymer obtained by graft-polymerizing (meth) acrylamide onto a (meth) acrylic acid-based copolymer is used.

The copolymers used in the dispersants described in these publications do not use (meth) acrylamide type monomers as their respective copolymerization components, or they are directly copolymerized with other copolymerization components. Although it is not an ordinary copolymer that is polymerized, the reason is that it is difficult to copolymerize (meth) acrylamide-based monomer and styrene by a known polymerization method, and even if (meth) acrylic acid is added to this, it is improved. This is because the desired performance cannot be obtained. Therefore, in JP-A-7-258994, a styrene- (meth) acrylic acid-based copolymer is once synthesized, and then (meth) acrylamide is graft-polymerized thereto. Thus, a rosin emulsion sizing agent containing a dispersant using a copolymer having no (meth) acrylamide-based monomer as a copolymer component or having only a graft component has a wide range of pH.
There is a tendency that the sizing degree is not sufficiently imparted to the paper in the area, and the stability when subjected to mechanical shearing force and the stability when diluted with hard water are not sufficient, and there are many foaming in the paper making process. There is a problem.

[0004]

Specifically, conventional sizing agents include, for example, anionic rosin-based sizing agents, particularly solution-type rosin sizing agents which are alkaline neutralized products of fortified rosins, When using a dispersion-type rosin-based sizing agent that is more effective in size than a solution-type rosin-based sizing agent and has a wide paper application pH range, the drying conditions cannot be said to be sufficient during papermaking using a high-speed paper machine. In order to obtain the sizing degree, it is necessary to increase the amount of the sizing agent added, which not only raises the cost but also causes a problem of remarkable foaming in the papermaking process. Under such circumstances, when the papermaking speed is high and the drying conditions are relatively gentle, for example, a paper machine having a Yankee dryer (for example, a paper machine for pure white roll paper) or an ultra-high speed newsprint paper machine is used. There is a strong demand for a rosin-based emulsion sizing agent that exerts an excellent sizing effect on used paper.

A first object of the present invention is to provide a rosin emulsion which exhibits an excellent sizing effect even though it is applied to a papermaking system in which drying conditions are relatively mild, as in the case of papermaking with a high speed papermaking machine. It is to provide a composition, a method for sizing paper, and a paper. The second object of the present invention is to adjust the pH.
(4) To provide a rosin-based emulsion composition, a paper sizing method, and a paper which exhibit an unprecedented excellent size effect even in a papermaking system having a wide pH range from acidic to alkaline papermaking of pH 4. A third object of the present invention is to provide a rosin-based emulsion composition that exhibits unprecedented excellent dispersion stability, and has a low dispersion viscosity and is easy to handle, a method for sizing paper using the same, and a paper. It is in. A fourth object of the present invention is to provide a rosin emulsion composition having less foaming than ever before in a papermaking process, a method for sizing paper using the same, and a paper. A fifth object of the present invention is to provide a rosin-based emulsion composition which is more excellent than ever in storage stability and mechanical stability in a papermaking process, and a paper sizing method and paper using the same. To provide.

[0006]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventor has found that not only (meth) acrylamide-based monomers not only styrene-based monomers and (meth) acrylic acid but also ( It was found that when copolymerized with (meth) acrylic acid ester, a copolymer in which (meth) acrylamide was well copolymerized with other components was obtained, especially when the ratio of these components was within a specific range, and this copolymer was contained. It was found that the above-mentioned problems can be improved by using a dispersant, and the present invention has been completed. That is, the present invention provides (1), a rosin-based substance (A)
And a rosin emulsion composition containing the dispersant (B), the dispersant (B) is a styrene monomer (a) and a (meth) acrylic acid ester monomer (b).
And a copolymer obtained by copolymerizing a (meth) acrylamide-based monomer (c) with a monomer having a monomer (d) of (meth) acrylic acid and / or a salt thereof in a monomer structure, and / or a neutralized product thereof. The present invention provides a rosin-based emulsion composition containing Further, the present invention is
(2), (meth) acrylamide-based monomer (c) component is 5 to 30% by weight based on the total monomers (a) to (d), the rosin-based emulsion composition of (1), (3), styrene-based The monomer (a) component is 5 to 60% by weight, and the (meth) acrylic acid ester-based monomer (b) component is 5 to 6
0% by weight, 5 to 30% by weight of the (meth) acrylamide monomer (c) component and 5 to 30% by weight of the monomer (d) component of the (meth) acrylic acid and / or its salt. The rosin emulsion composition, (4), and the (meth) acrylic acid ester monomer (b) component is normal butyl acrylate, isobutyl acrylate, tertiary butyl acrylate, 2-ethylhexyl acrylate and 2-ethylhexyl methacrylate (1). To (3), the rosin emulsion according to any one of (1) to (4), wherein (5) the (meth) acrylamide monomer (c) component is (meth) acrylamide. The composition, (6) (a)-(d) is 2,4-diphenyl-
A rosin-based emulsion composition according to any one of (1) to (5) above, which is copolymerized in the presence of 4-methyl-1-pentene (e) and an alkyl mercaptan (f).
(7) A method for sizing paper, which comprises adding the rosin emulsion composition according to any one of (1) to (6) to a pulp slurry having a pH range of 4 to 8, and (8) rosin substance (A). And a paper containing the copolymer according to any one of the above (1) to (6) and / or a neutralized product thereof.

The (A) rosin-based substance in the present invention is
The rosin itself and a reaction product (rosin modified product) using rosin as a reaction component and their reinforced rosin and rosin ester are referred to and are used alone or as a mixture of two or more kinds. Examples of the rosin itself include gum rosin, tall oil rosin, and wood rosin, which may be used alone or as a mixture of two or more kinds. Examples of the modified rosin include those obtained by partially or substantially completely hydrogenating the above-mentioned rosin, those disproportionated, those polymerized, and those modified with formaldehyde.

The toughened rosin is a product obtained by adding the α, β-unsaturated carboxylic acid to the above-mentioned rosin or modified rosin. Typical examples of the α, β-unsaturated carboxylic acid used here include unsaturated dibasic acids such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, itaconic anhydride, citraconic acid and citraconic anhydride. , Unsaturated monobasic acids such as acrylic acid and methacrylic acid,
These may be used alone or in combination of two or more.

Examples of rosin esters include reaction products of at least one of the above rosins and modified rosins or reinforced rosins with at least one selected from polyhydric alcohols such as glycerin and pentaerythritol and epoxy compounds. . Further, a reinforced rosin ester obtained by addition reaction of the above rosin ester with an α, β-unsaturated carboxylic acid is also included. When the rosin-based substance contains rosin esters, the size effect tends to be better in a weakly acidic or neutral papermaking system than that which does not contain this. In the acidic papermaking system having a pH of 4 to 6, it is preferable not to include rosin esters from the viewpoint of size effect.

Among the monomers constituting the copolymer and / or the neutralized product thereof contained in the dispersant, styrenes such as styrene, α-methylstyrene, vinyltoluene, and divinylbenzene as the styrene-based monomer (a). And one or more of these are used.
Of these, styrene and α-methylstyrene are preferable.

Among the monomers constituting the copolymer and / or the neutralized product thereof contained in the dispersant, the (meth) acrylic acid ester-based monomer (b) is ethyl acrylate, normal propyl acrylate, isopropyl acrylate, Normal butyl acrylate, isobutyl acrylate, tertiary butyl acrylate, hexyl acrylate, cyclohexyl acrylate, heptyl acrylate, octyl acrylate, 2-ethylhexyl acrylate, nonyl acrylate, dodecyl acrylate, methyl butyl acrylate, (mono-
Or di-alkyl) aminoalkyl acrylate and other acrylic acid ester-based monomers, methyl methacrylate,
Ethyl methacrylate, normal propyl methacrylate, isopropyl methacrylate, normal butyl methacrylate, isobutyl methacrylate, tertiary butyl methacrylate, pentyl methacrylate, hexyl methacrylate, cyclohexyl methacrylate,
Methacrylic acid ester-based monomers such as octyl methacrylate, 2-ethylhexyl methacrylate, decyl methacrylate, (mono- or di-alkyl) aminoalkyl methacrylate, hydroxyethyl methacrylate and the like can be mentioned, and one or more of these can be used. Of these, normal butyl acrylate, isobutyl acrylate, tertiary butyl acrylate,
2-ethylhexyl acrylate and 2-ethylhexyl methacrylate are preferred.

Among the monomers constituting the copolymer contained in the dispersant and / or the neutralized product thereof, the (meth) acrylamide monomer (c) is (meth) acrylamide, N-isopropylacrylamide or N-tertiary. At least one N-substituted (meth) acrylamide such as lyoctyl acrylamide can be used. Of these, acrylamide is preferred.

Among the monomers constituting the copolymer and / or the neutralized product thereof contained in the dispersant, the monomer (d) of (meth) acrylic acid and / or its salt is acrylic acid, methacrylic acid or the like. At least one salt obtained by neutralizing ## STR3 ## with a basic substance is exemplified, and examples of the basic substance include sodium, potassium, ammonium, methylamine, dimethylamine, trimethylamine, ethylamine, diethylamine, triethylamine, propylamine, Butylamine, monoethanolamine, diethanolamine, triethanolamine and the like,
These 1 type (s) or 2 or more types are used. Of these, methacrylic acid and / or its sodium salt, potassium salt, ammonium salt, and monoethanolamine salt are preferable.

In the present invention, as the monomer constituting the copolymer contained in the dispersant and / or the neutralized product thereof, other monomers copolymerizable with the above (a) to (d) can be used in combination. Such monomers include dialkyl esters of unsaturated dicarboxylic acids such as maleic acid and fumaric acid, hydrophobic monomers such as vinyl esters such as vinyl acetate and vinyl propionate, crotonic acid, maleic anhydride, maleic acid, Α, β-Unsaturated carboxylic acids such as fumaric acid, itaconic acid and citraconic acid, monomethyl maleate, monoethyl maleate, monopropyl maleate, monobutyl maleate, monomethyl fumarate, monoethyl fumarate, monopropyl fumarate, Carboxyl group-containing monomers such as α, β-unsaturated dicarboxylic acid half-esters such as monobutyl fumarate, monomethyl itaconate, monoethyl itaconate, monopropyl itaconate and monobutyl itaconate, vinyl sulfonic acid, (meth)
Sulfonic acid group-containing monomers such as allylsulfonic acid, 2-acrylamido-2-methylpropanesulfonic acid and styrenesulfonic acid, phosphoric acid ester group-containing monomers such as phosphoric acid ester of hydroxyalkyl (meth) acrylate, and alkali compounds thereof Anionic monomer such as salt, aminoalkyl (meth) acrylate,
Examples thereof include cationic monomers such as aminohydroxyalkyl (meth) acrylate, vinylpyridine, vinylimidazole and diallylamine, and nonionic monomers such as N-vinylformamide and vinylpyrrolidone. For example, in the case of an aqueous emulsion composition of a rosin-based substance, the amount used may be in a range that does not reduce the size effect as a sizing agent, and specifically, it is usually 10% by weight or less of all monomers (at most, at most). 10% by weight, and so on)
It is preferably at most 5% by weight.

The amounts of the components (a) to (d) used are preferably 5 to 60% by weight of the component (a) and 5 in the component (b).
˜60 wt%, 1 to 30 wt% of component (c) and (d)
The component is 5 to 30% by weight, and more preferably (a)
5-60% by weight of component, 5-60% by weight of component (b),
5-30% by weight of component (c) and 5-30% of component (d).
% By weight. The weight% may be parts by weight.

When the above monomers are copolymerized in the presence of 2,4-diphenyl-4-methyl-1-pentene (e) and alkyl mercaptan (f), a copolymer and / or a neutralized product thereof is formed. It is known that it is easy to control the molecular weight at that time, but a dispersant containing the copolymer obtained in the present invention and / or a neutralized product thereof is used in combination with these compounds. Thereby, when the rosin-based substance is emulsified and dispersed in water, finer emulsion production of particles becomes possible better, and economically a rosin-based emulsion composition in which precipitates and aggregates are more difficult to occur is obtained. , More suitable as a sizing agent. Examples of the alkyl mercaptan (f) include n-octyl mercaptan, tertiary decyl mercaptan,
Examples thereof include n-dodecyl mercaptan and n-octadecyl mercaptan, and one or more of these may be used. In particular, n-dodecyl mercaptan and tertiary decyl mercaptan are preferable. When synthesizing the copolymer contained in the dispersant (B) and / or the neutralized product thereof, a chain transfer agent other than the above-mentioned components (e) and (f) can be used in combination. For example, thioglycolic acid derivative, mercaptopropionic acid derivative, mercaptan derivative such as mercaptoethanol, thiomalic acid and thiosalicylic acid, carbon tetrachloride, carbon tetrabromide, bromotrichloroethane, halogenated hydrocarbon such as bromobenzene, trimethylamine, triethylamine. Amines such as tripropylamine, tributylamine, N, N-dimethylaniline and N, N-diethylaniline, m
Examples include nitro compounds such as dinitrobenzene, aldehydes, sulfides, sulfoxides, sulfones, allyl compounds, anthracene, cumene, and diphosphorous acid (salt). 0.1 to 3 mol% of the component (e) based on the total weight of the components (a) to (d),
It is preferable to use the component (f) in an amount of 0.1 to 3 mol%.

In producing the copolymer contained in the dispersant and / or its neutralized product, the polymerization method may be any of emulsion polymerization, solution polymerization, suspension polymerization and bulk polymerization, but emulsion polymerization preferable. A known surfactant can be used as an emulsifier for emulsion polymerization. As the surfactant, those applicable to emulsion polymerization can be usually used, and examples thereof include nonionic, anionic and amphoteric surfactants, but surfactants having a polymerizable group can also be used. This surfactant can be used alone or in combination of two or more.

Examples of the nonionic surfactants include polyoxyalkylene alkylphenyl ether, polyoxyalkylene alkyl ether, polyoxyalkylene fatty acid ester, polyoxypropylene polyoxyethylene glycol glycerin fatty acid ester, sorbitan fatty acid ester, polyethylene glycol fatty acid. Examples thereof include esters, polyoxyethylene sorbitan fatty acid esters, sucrose fatty acid esters, pentaerythritol fatty acid esters, propylene glycol fatty acid esters, fatty acid diethanolamides, and polyoxypropylene polyoxyethylene glycol. One of these nonionic surfactants may be used alone, or two or more thereof may be used in combination.

Examples of the anionic surfactant include compounds such as polyoxyalkylene alkylphenyl ether, polyoxyalkylene monostyryl phenyl ether, polyoxyalkylene distyryl phenyl ether, polyoxyalkylene alkyl ether and polyoxyalkylene fatty acid ester. Phosphate ester salts, sulfonate salts, succinic acid ester salts and sulfosuccinic acid ester salts, alkylbenzene sulfonate salts, naphthalene sulfonic acid formalin condensate salts, alkenyl succinic acid salts, rosin salts, reinforced rosin salts and hexyl diphenyl ether disulfonic acid, decyl Alkyl diphenyl ethers such as diphenyl ether disulfonic acid, dodecyl diphenyl ether disulfonic acid and hexadecyl diphenyl ether disulfonic acid Sulfonic acid compounds and can be exemplified salts of these compounds. Examples of the salt include alkali metal salts such as sodium salt and potassium salt, ammonium salt, amine salt and the like. One of these anionic surfactants may be used alone, or two or more thereof may be used in combination.

Examples of the amphoteric surfactant include surfactants having an anionic group and a cationic group, and those in which the anionic group is an alkali metal salt such as sodium salt or an amine salt. You can
These may be used alone or in combination of two or more. As the surfactant having a polymerizable group, a compound which is generally called a reactive emulsifier and has a hydrophobic group, a hydrophilic group and a polymerizable group in the molecule can be mentioned. Examples of the polymerizable group include (meth)
Examples of the polymerizable group include a functional group having a carbon-carbon double bond such as an allyl group, a 1-propenyl group, a 2-methyl-1-propenyl group, an isopropenyl group, a vinyl group and a (meth) acryloyl group. As the surfactant having a polymerizable group, those which can be applied to emulsion polymerization can be used, and are not particularly limited, but as a specific example, having one or more polymerizable groups in the molecule, Polyoxyalkylene ether compounds such as polyoxyalkylene alkyl ethers, polyoxyalkylene aralkyl ethers and polyoxyalkylene phenyl ethers, and polyoxyalkylenes such as polyoxyalkylene monostyryl phenyl ethers and polyoxyalkylene distyryl phenyl ethers. Examples thereof include styryl phenyl ether compounds. In addition, sulfonic acid salts, sulfuric acid ester salts, phosphoric acid ester salts and sulfosuccinic acid ester salts derived from these polymerizable group-containing polyoxyalkylene ether compounds and the polyoxyalkylene styrylphenyl ether compounds,
Aliphatic carboxylic acid salts and aromatic carboxylic acid salts derived from the polymerizable group-containing polyoxyalkylene ether compound, acidic phosphoric acid (meth) acrylic acid ester-based compounds, rosin-glycidyl (meth) acrylate-based compounds, and the like. It can be illustrated. These surfactants may be used alone or in combination of two or more.

When synthesizing the copolymer contained in the above dispersant and / or its neutralized product, the solvent is water and toluene, hexane, benzene, isopropyl alcohol,
Examples of the organic solvent include ethanol and acetone. Further, as the polymerization initiator used in the polymerization,
Persulfates such as ammonium persulfate, potassium persulfate and sodium persulfate, peroxides such as tert-butyl hydroperoxide, redox polymerization catalysts obtained by combining these persulfates or peroxides with reducing agents, and 2. , 2'-Azobisisobutyronitrile and 2,2'-
Examples thereof include azo catalysts such as azobis-2-methylpropionamidine dihydrochloride, etc., but are not particularly limited thereto, and other known and commonly used polymerization initiators can also be used. These polymerization initiators may be used alone or in combination of two or more.

The amount of the above-mentioned polymerization initiator to be used is usually 0.01 to 5 mol based on the total amount of the monomers used in the synthesis of the copolymer and / or its neutralized product contained in the above-mentioned dispersant. %. The polymerization initiator may be charged together with the monomer into the reaction vessel at once, or may be continuously added dropwise. As a method for adding the monomers used in this polymerization, a batch addition polymerization method in which all the monomers are charged in a reaction vessel at a time and polymerized, or a part or all of the monomers are divided and added to the reaction vessel to perform polymerization An addition polymerization method, a continuous dropping polymerization method in which a part or all of a monomer is continuously dropped into a reaction vessel to perform polymerization, and the like can be used.

The monomer concentration during this polymerization is usually 15 to
It is 50% by weight. It is possible to obtain a copolymer and / or a neutralized product thereof at a concentration of 15% by weight or more by polymerizing at a monomer concentration of less than 15% by weight and concentrating, but it is not preferable from the economical point of view. Further, when the polymerization is carried out at a monomer concentration exceeding 50% by weight, it may be difficult to control the heat of polymerization. The polymerization reaction temperature is usually 40 to 95 ° C,
It is preferably 50 to 90 ° C., and the reaction time is 1 to 20.
It's time. In the case of neutralizing the copolymer, the neutralization reaction at that time is usually at a reaction temperature of 60 to 90 ° C,
The reaction time is 0.5 to 4 hours. When the polymer portion corresponding to (meth) acrylic acid of the copolymer is neutralized after completion of the polymerization, 0.6 to 1 is used for the equivalent of the anionic group of the (meth) acrylic acid, that is, the anionic equivalent. Equivalent weights are preferred.

The above emulsifying dispersant is the above copolymer and / or
Or a neutralized product thereof, which is usually obtained as a solid content concentration of 15 to 50% by weight, and usually has a viscosity (measured value by a Brookfield rotary viscometer at 25 ° C.) of 10 to 10,000 mPas at a solid content concentration of 20% by weight. · S and pH 6
~ 11.

The rosin emulsion composition of the present invention is
At least the above components (A) and (B) are used, and the amount of each used is 70 to 99% by weight of the component (A), (B)
The component is preferably 1 to 30% by weight. If the amount of the component (B) is less than 1 part by weight, the effects on the size performance, mechanical stability, etc. may be lower than those in the above range.
If the amount is more than the weight part, the influence on the size performance tends to reach a peak, which is economically unfavorable. Known polymeric emulsifying dispersants, low molecular emulsifying dispersants, polymeric surfactants, low molecular surfactants and the like may be used in combination within a range that does not impair the effects of the present invention.

The method for producing the rosin emulsion composition of the present invention is not particularly limited. For example, the component (A) is mixed with a solvent (in accordance with the method described in JP-B-54-36242). For example, a method of producing an oil-in-water emulsion (solvent method) by dissolving it in benzene, toluene, methylene chloride, etc., adding the component (B) and then passing it through a homogenizer, the method described in JP-A-54-77209. According to the method, the component (B) is mixed with the melted component (A) to form a water-in-oil emulsion, and inversion water is added to cause a phase transition to an oil-in-water emulsion (phase inversion method), JP-B-53. According to the method described in JP-A-32380, after melt-mixing the components (A) and (B),
Under high temperature and high pressure (for example, 130-200 ℃, 150-100
Method for producing oil-in-water emulsion (mechanical method) through homogenizer at 0 kg / cm ² )
According to the method described in JP-A-0-226981, a method of producing an oil-in-water emulsion by passing components (A) and (B) through a high-shear rotary emulsion disperser (mechanical method), etc. Is used.

The particle size of the resulting emulsion (the cumulative 50% size in the weight-based particle size distribution) is 1 μm or less, preferably 0.5 μm or less. When the particle size is more than 1 μm, precipitation is likely to occur during storage and mechanical stability may be poor. The particle size can be measured, for example, with a laser diffraction / scattering particle size distribution analyzer LA-910 (manufactured by Horiba Ltd.).

The rosin-based emulsion composition thus obtained has excellent storage stability and mechanical stability when used as a sizing agent, and is applied to a wet paper under relatively mild drying conditions in a high-speed paper machine. Relatively less heat
For example, when used in a paper machine having a Yankee dryer or a paper machine for ultra-high speed newsprint,
6, especially at pH 4.5 to 5.0, that is, in a so-called acidic papermaking system, performance such as sizing effect is excellent as compared with conventional sizing agents. In addition, sizing performance is also superior to conventional sizing agents in weakly acidic papermaking systems and neutral papermaking systems. The emulsion composition of the present invention can be used as a sizing agent even if the papermaking pH is less than 4 or the papermaking pH is more than 8, but those within the above range are preferable in terms of sizing effect. Further, when the emulsion composition of the present invention is used as a sizing agent, it is characterized in that papermaking tools such as press rolls and dryer canvases are less contaminated.

In the sizing method of the present invention, the rosin emulsion composition of the present invention is used as a sizing agent to produce paper having a pH of 4 to 4.
In the manufacturing process of various papers and paperboards in No. 8, for example, by adding to the wet end part. Specifically, the sizing agent of the present invention is added to an aqueous dispersion of pulp (pulp slurry) in an amount of 0.01 based on its dry weight.
.About.5% by weight, preferably 0.05 to 2% by weight.

The sized paper of the present invention uses the rosin-based emulsion composition described above as a sizing agent, and in the presence of van sulphate (and also in the presence of a cationic chemical such as a cationic polyacrylamide, a sulfuric acid band is not always formed). It does not need to be present) Preferably, the sizing agent of the present invention is added at 0.05% to 2% by weight with respect to the pulp solid content to make the papermaking pH.
Papermaking from 4 to pH 8 exhibits superior sizing performance compared to paper sized using conventional rosin-based sizing agents.

The sizing paper obtained by using the sizing agent is not particularly limited, but various kinds of paper (including paperboard) can be mentioned. The types of paper include recording paper such as PPC paper, ink jet printing paper, laser printer paper, foam paper, thermal transfer paper, heat-sensitive recording base paper, pressure-sensitive recording base paper, and its base paper, art paper, cast coated paper,
Coated base paper such as high-quality coated paper, kraft paper, wrapping paper such as pure white roll paper, other notebook paper, book paper, various printing paper, various paper (newspaper) such as newspaper, Manila ball,
Examples include paperboard paperboard such as white balls and chip balls, and paperboard such as liner and gypsum board base paper. Further, the sizing agent of the present invention includes a surface sizing agent as a subordinate concept thereof, and when it is used as a surface sizing agent, it is applied to a paper preliminarily made by a conventional method such as spraying, dipping or coating.

In the production of paper or paperboard, the pulp raw materials are bleached or unbleached high-yield pulp such as bleached or unbleached chemical pulp such as kraft pulp or sulfite pulp, groundwood pulp, mechanical pulp or thermomechanical pulp. Any of used pulp such as used newspaper, used magazine, used corrugated cardboard or deinked used paper can be used. Further, a mixture of the above pulp raw material and synthetic fibers such as asbestos, polyamide, polyimide, polyester, polyolefin and polyvinyl alcohol can also be used.

Additives such as a filler, a dye, a dry paper strength improver, a wet paper strength improver, a retention improver, and a drainage improver are also necessary in order to exhibit the physical properties required for each paper type. You may use according to it. As a filler, clay, talc,
Calcium carbonate, white carbon, etc. may be mentioned, and these may be used alone or in combination of two or more kinds.
Examples of the dry paper strength improver include anionic polyacrylamide, cationic polyacrylamide, amphoteric polyacrylamide, cationized starch, and amphoteric starch. These may be used alone or in combination of two or more kinds. good.
Examples of the wet paper strength improver include polyamide / epichlorohydrin resin, melamine / formaldehyde resin, urea / formaldehyde resin, etc. These may be used alone or in combination with anionic polyacrylamide. Examples of the yield improver include anionic or cationic high molecular weight polyacrylamide, a combination of silica sol and cationized starch, a combination of bentonite and cationic high molecular weight polyacrylamide, and the like. Examples of the drainage improving agent include polyethyleneimine, cationic or amphoteric or anionic polyacrylamide, and the like. Also,
If necessary, starch, polyvinyl alcohol, polyacrylamide, dye, coating color, surface sizing agent, anti-slip agent, etc. may be applied using a size press, gate roll coater, bill blade coater, calender or the like. Further, the bansulfate may be used before, after, or simultaneously with the addition of the sizing agent of the present invention.

[0034]

BEST MODE FOR CARRYING OUT THE INVENTION As the component (A), rosins fortified with unsaturated dibasic acid, rosin esters using polyhydric alcohol, and a mixture of both are used. Further, as the component (B), 5 to 60 parts by weight of styrene and / or α-methylstyrene as the component (a), and n-butyl (meth) acrylate, isobutyl methacrylate and 2- as the component (b) are used. 5 to 60 parts by weight of at least one of ethylhexyl acrylate, 5 to 30 parts by weight of at least one of acrylamide, N-tert-octyl acrylamide and N-isopropyl acrylamide as the component (c), and (d) as the component (d) Polymerization was carried out using 5 to 30 parts by weight of (meth) acrylic acid in the presence of 2,4-diphenyl-4-methyl-1-pentene and / or alkyl mercaptan as a chain transfer agent, or in the presence of these and mercaptoethanol. Copolymer, or even less of caustic soda, caustic potash and ammonia Kutomo one using dispersants containing neutralized product of the copolymer obtained by neutralizing an equivalent ratio 0.6 to 1 with. 70 to 99% by weight of the component (A) and 1 to 30% by weight of the component (B) are dispersed in an aqueous dispersion medium (mainly water) to obtain a rosin emulsion composition.
Using this rosin emulsion composition, papermaking pH 4
Paper is made in ~ 8 to obtain sized paper.

[0035]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. Further, unless otherwise specified, all parts and percentages in each example are by weight.

Production Example of Rosin-Based Substance (A) Production Example 1 (Production of Fumaric Acid-Reinforced Rosin-Based Substance (A-1)) 90 parts of fumaric acid was gradually added to 350 parts of gum rosin in a molten state at 200 ° C. After stirring and keeping the temperature at 200 ° C. for 2 hours, 560 parts of formaldehyde-treated (modification rate 1%) tall oil rosin was further added, and the mixture was melted and stirred to be homogeneously mixed,
The reaction product obtained thereafter was cooled to room temperature. This reaction product is a fumaric acid-enhanced rosin containing 9% fumaric acid, and is referred to as a fumaric acid-enhanced rosin-based substance (A-1).

Production Example 2 (Production of glycerin ester of rosin substance) 600 parts of gum rosin having an acid value of 170 and 55 parts of glycerin were charged into a flask equipped with a stirrer, a thermometer, a nitrogen introducing tube, a water diverter and a condenser. An esterification reaction was carried out at 270 ° C. for 15 hours to obtain a reaction product of glycerin ester of rosin substance.

Production Example 3 (Production of Maleic Anhydride-Reinforced Rosin and Rosin Ester Mixture (A-2)) 6 parts of maleic anhydride was added to 69 parts of gum rosin in a molten state at 200 ° C., and the mixture was kept warm with stirring at 200 ° C. for 2 hours. After doing
25 parts of the rosin ester of Production Example 2 was added and stirred and mixed in a molten state to obtain a mixture (A-2) in which the ratio of 8% maleic anhydride reinforced rosin and rosin ester was 75:25 by weight.

Production of Dispersant (B) for Examples Production Example 1 (Production of Dispersant (B-1)) 3.52 parts of styrene and 3 parts of butyl methacrylate were placed in a flask equipped with a stirrer, a thermometer and a nitrogen gas inlet tube. .52
Parts, 50% acrylamide 14.07 parts, 80% methacrylic acid 4.40 parts, normal dodecyl mercaptan 0.
12 parts (0.3 mol% of monomer), 0.04 part of sodium dodecylbenzene sulfonate, 1.13 parts of ammonium persulfate were charged, and water 6 was added so that the solid content concentration became 21%.
3.08 parts were added, and the mixture was stirred and mixed, and heated at 90 ° C. for 3 hours. Then, the mixture was cooled to 70 ° C., and it was 1.0 equivalent to the anion equivalent of methacrylic acid, and 8.12 parts of 25% aqueous sodium hydroxide solution and 1.96 parts of water were gradually added dropwise so that the solid content concentration became 20%. Then, the mixture is stirred for 30 minutes and then cooled to room temperature to give a solid content of 20.1% and a viscosity of 5
A polymer emulsion dispersant (B-1) having a viscosity of 700 mPa · s and a pH of 9.7 was obtained. Each of the components used, the equivalent ratio,
The measured values of the solid content, viscosity and pH are shown in Tables 1 and 2. The viscosity was 25 using a Brookfield rotational viscometer.
It is the measured value of ° C.

Production Examples 2-12 for Examples (Dispersant (B-
2) to Production of (B-12)) Monomers, chain transfer agents, and the like in Production Example 1 of the above dispersant,
Except that the alkalis are made to have the composition ratio in the corresponding column of Table 1 and the amount of the alkalis charged is the amount equivalent to the anion equivalent of (meth) acrylic acid in the corresponding column of Table 1. A copolymer dispersion was produced in the same manner as in Production Example 1 of Dispersant above, and polymer emulsion dispersants (Production Examples 2 to 12) were obtained. Tables 1 and 2 show the results of the same measurement as in Dispersant Production Example 1.

Comparative Examples Production Examples 13 to 17 (dispersant (B-
13) to (B-17) Production) Monomers, chain transfer agents in Production Example 1 of the dispersant described above,
Except that the alkalis were made to have the composition shown in the corresponding column of Table 1 and the amount of the alkalis was set to the equivalent ratio to the anion equivalent of (meth) acrylic acid in the corresponding column of Table 1. A copolymer dispersion was produced in the same manner as in Production Example 1 above, and a polymer emulsion dispersant (Production Example (B-1
3)-(B-17) were obtained. Tables 1 and 2 show the results of the same measurement as in Dispersant Production Example 1.

[0042]

[Table 1]

[0043]

[Table 2]

Production Example 18 for Comparative Example (Dispersant (B-18))
Preparation of 78.2 parts of styrene and 21.8 parts of acrylic acid were charged in a reaction vessel, the temperature was gradually raised with stirring, and the reaction was carried out at 100 ° C. to 120 ° C. for 1.5 hours. Cooled to ℃,
Immediately, the mixture is placed in a polymerization dish and reacted at 130 ° C to 140 ° C for 8 hours. After completion of the reaction, the obtained polymer is cooled and pulverized. Then, 7.5 parts of the obtained polymer and 30 parts of water are charged into an emulsifying vessel, 1.5 parts of 25% aqueous ammonia is added with stirring, and a neutralization reaction is carried out at 70 ° C. for 3 hours. After the completion of the neutralization reaction, the reaction system is cooled to about 40 ° C. Then 4
After charging 18.7 parts of 0% acrylamide aqueous solution and 43.8 parts of water and raising the temperature in the reaction system to 65 ° C., 0.04 part of ammonium persulfate was added, and the reaction was carried out at 70 ° C. to 75 ° C. for 4 hours. To do. The polymer obtained has a solid content of 15% and a viscosity of 5
00 cps (100 using BH type viscometer No. 3 rotor
It was measured by rotation).

Comparative Production Example 19 (Dispersant (B-19))
Manufacture of) A copolymer dispersion is prepared by batch polymerization so that the monomers and alkalis in Production Example 1 of the above-mentioned dispersant have a composition corresponding to that of the dispersant (B-18) of Production Example 18 for Comparative Example. Manufactured. The obtained polymer has a solid content of 15% and a viscosity of 9800 m.
High molecular weight emulsifying dispersant with Pa · s and pH 9.7 (B-19)
Got

Example 1 (Production Example 1 of rosin emulsion composition) The above rosin substance (A-1) was heated and melted at about 160 ° C., and the polymer system obtained in Production Example 1 was stirred while stirring. The dispersant (B-1) was added so as to be 6% based on the total solid content and mixed to obtain a water-in-oil emulsion. While stirring, hot water was gradually added to cause phase inversion to form an oil-in-water emulsion, and hot water was further added and mixed rapidly to form a stable oil-in-water emulsion. An aqueous emulsion composition of the base material was obtained. The thus-obtained rosin-based emulsion composition had a solid content of 50.9%, a viscosity of 58 mPa · s, a pH of 5.8, and an average particle diameter of 0.32 μm. This rosin emulsion composition is used as it is as a sizing agent. Table 3 shows these measured values. The viscosity is a value measured at 25 ° C using a Brookfield rotational viscometer.

Examples 2 to 12 (Production Examples 2 to 12 of rosin emulsion composition) The polymer dispersant (B-1) was replaced with the polymer dispersants (B-2) to (B- A rosin-based emulsion composition was obtained in the same manner as in Example 1 except that each of 12) was replaced. The results of measuring the obtained rosin-based emulsion composition in the same manner as in Example 1 are shown in Table 3.

Comparative Examples 1 to 6 (Production Examples 13 to 18 of rosin emulsion composition) The polymeric dispersant (B-1) was replaced with the polymeric dispersants (B-13) to (B- A rosin-based emulsion composition was obtained in the same manner as in Example 1 except that each of 18) was replaced. The results of measuring the obtained rosin-based emulsion composition in the same manner as in Example 1 are shown in Table 3.

Comparative Example 7 Rosin was prepared in the same manner as in Example 1 except that the polymeric dispersant (B-1) was replaced by the polymeric emulsifying dispersant (B-19) prepared in Comparative Production Example 19. Although the emulsion emulsion composition was produced, a rosin emulsion that could be used due to poor emulsification and dispersion was not obtained.

Examples 13 to 24 (Production Examples 13 to 24 of rosin-based emulsion composition) The rosin-based substance (A-1) was replaced with a maleic anhydride-reinforced rosin-rosin ester mixture (A-2), and a polymer was used. The system dispersant (B-1) is replaced with the polymer dispersants (B-1) to (B-1).
A rosin-based emulsion composition was obtained in the same manner as in Example 1 except that each of 2) was replaced. The results of measuring the obtained rosin emulsion composition in the same manner as in Example 1 are shown in Table 4.

Comparative Examples 8 to 13 The polymer dispersant (B-1) was replaced with (B-13) by replacing the rosin-based substance (A-1) with a mixture (A-2) of maleic anhydride reinforced rosin and rosin ester. ) To (B-18), respectively, to obtain a rosin emulsion composition in the same manner as in Example 1. The results of measuring the obtained rosin emulsion composition in the same manner as in Example 1 are shown in Table 4.

Comparative Example 14 A rosin-based substance (A-1) was used as a maleic anhydride-reinforced rosin and a rosin ester mixture (A-2), and a polymeric dispersant (B-1) was prepared in Comparative Production Example 19. A rosin-based emulsion composition was produced in the same manner as in Example 1 except that the polymer emulsion dispersant (B-19) was used, but a rosin-based emulsion resistant to use was not obtained due to poor emulsion dispersion. It was

Using each rosin emulsion composition which is an aqueous emulsion of the rosin substance obtained in the above Examples, Comparative Examples and Reference Examples, a size effect test, mechanical stability test, static stability test, The results of the foamability test and the hard water dilution stability test are shown in Table 5 (Examples 25 to 36 (Example 1).
~ 12 using sizing agent corresponding to each), Comparative Example 1
5 to 20 (using a sizing agent corresponding to each of Comparative Examples 1 to 6), Table 6 (using a sizing agent corresponding to each of Examples 13 to 24), Comparative Examples 21 to 26
(Use of a sizing agent corresponding to each of Comparative Examples 8 to 13)
Shown in.

(Size effect test 1) Bleached kraft pulp (mixed pulp having a pulp ratio of softwood to hardwood of 1: 9) has a hardness of 100 p so that the pulp concentration becomes 2.5%.
Diluted with pm dilution water and beaten using a beater to 38
It was set to 0. Next, 1.2 liters of the obtained pulp slurry was weighed in a disintegrator and, under stirring, ND talc (manufactured by Nippon Talc Co., Ltd.) was 3% with respect to pulp, and vanadium sulfate was 1.5% with respect to pulp.
After the addition, rosin-based emulsion compositions of Examples 1 to 12 and Comparative Examples 1 to 6 of the above Examples and Comparative Examples were added as a sizing agent to each of 0.25% of pulp, as shown in Table 3. Then, the obtained pulp slurry was diluted to a concentration of 0.25% with diluted water having a pH of 4.5, and a cationic polyacrylamide (a paper strength enhancer DS477 of Nippon PMC Co., Ltd.) was used as a fixing agent for pulp. 0.05%
Add and paper making pH 4.5 with Noble and Wood machine
The wet paper obtained is dried at 100 ° C. for 80 seconds using a drum dryer, and the basis weight is 70 g / m ^2.
The test papers containing the sizing agent were obtained from the rosin emulsion compositions of the above Examples and Comparative Examples. Each of the obtained test papers was subjected to constant temperature and humidity (23 ° C, relative humidity 50
%) After conditioned for 24 hours in an environment, the sizing degree was measured by the Steckit method. The results obtained are shown in Table 5.

(Size effect test 2) Bleached kraft pulp (mixed pulp having a pulp ratio of softwood to hardwood of 1: 9) has a hardness of 100 p so that the pulp concentration becomes 2.5%.
Diluted with pm dilution water and beaten using a beater to 38
It was set to 0. Next, 1.2 liters of the obtained pulp slurry was weighed in a disintegrator and stirred to obtain light calcium carbonate (T
P121S (manufactured by Okutama Kogyo Co., Ltd.) was added to the pulp at 2%, and vansulfate was added to the pulp at 1.5% and the amphoteric starch (Cat) was added.
o3210 (Oji National Co., Ltd.) to pulp
% Of each of the above Examples and Comparative Examples, and then 0.3% of each rosin emulsion composition of Examples 13 to 24 and Comparative Examples 8 to 13 as a sizing agent was added to the pulp. . Then, the obtained pulp slurry was diluted to a concentration of 0.25% with diluting water having a pH of 7.5, and then light calcium carbonate (T) was added to the diluted pulp slurry.
P121S (Okutama Kogyo Co., Ltd.) against pulp 3%, ND
Talc (manufactured by Nippon Talc Co., Ltd.) 3% with respect to pulp, NR12MLS (manufactured by Hymo Co.) as a fixing agent 0.01% with respect to pulp
Add and paper making pH 7.5 with Noble and Wood paper machine
The wet paper obtained is dried with a drum dryer at 100 ° C. for 80 seconds, and the basis weight is 65 g / m ^2.
Test papers were obtained using the aqueous emulsion compositions of rosin-based substances using the dispersants of the above Examples and Comparative Examples. Each of the obtained test papers was kept at a constant temperature and humidity (23 ° C,
After conditioning the humidity for 24 hours in an environment (relative humidity 50%), the sizing degree was measured by the Steckit method. The obtained results are shown in Table 6.

(Stability test at rest) 100 ml of each rosin emulsion composition of each of the above Examples and Comparative Examples was separately put into a test tube having a length of 30 cm and an inner diameter of 2.1 cm, and allowed to stand for 2 months and then at the bottom. The height (cm) of the precipitated precipitate was measured. The obtained results are shown in Table 5 (Examples 1 to 12 and Comparative Examples 1 to 1).
No. 6 size results) and Table 6 (Examples 13-2).
4 and the results of using each sizing agent of Comparative Examples 8 to 13).

(Mechanical Stability Test) 50 g of each rosin emulsion composition of the above Examples and Comparative Examples was separately put in a cup, and the temperature was 25 ° C., the load was 25 kg, and the rotation speed was 800 rp.
A Marlon type stability test was conducted for 10 minutes at m. The generated agglomerates in each cup were filtered through a 325-mesh wire net to measure the amount of precipitation with respect to the total solid content in each cup, which was expressed as a percentage. The obtained results are shown in Table 5 (results using each sizing agent of Examples 1 to 12 and Comparative Examples 1 to 6) and Table 6 (each sizing agent of Examples 13 to 24 and Comparative Examples 8 to 13). Results).

(Foamability test 1) Bleached kraft pulp (mixed pulp having a pulp ratio of softwood to hardwood of 1 to 9) was diluted with diluting water having a hardness of 100 ppm to a pulp concentration of 2.5%, and a beater was used. And the beating degree was 380. Next, 1.2 liters of the obtained pulp slurry was weighed in a disintegrator and, under stirring, ND talc (manufactured by Nippon Talc).
After adding 3% to pulp and 1.5% to sulphate to sulphur, and then, as shown in Table 3 of the above Examples and Comparative Examples,
12, 0.25% of each rosin emulsion composition of Comparative Examples 1-6 was added to pulp separately. Then pH 4.
The resulting pulp slurry was diluted to a concentration of 0.2 with 5 dilution water.
It was diluted to 5% and placed in a cylindrical container. Then, 0.05% of a cationic polyacrylamide (Paper Strengthening Agent DS477, Nippon PMC Co., Ltd.) as a fixing agent was added to the diluted pulp slurry with respect to pulp of 0.05%, and the pulp slurry was circulated by a pump. This was dropped into the container from a height of 50 cm, and the area of bubbles accumulated on the liquid surface after 10 minutes was expressed as a percentage with respect to the entire liquid surface area. The results obtained are shown in Table 5.

(Expansion test 2) Bleached kraft pulp (mixed pulp having a pulp ratio of softwood to hardwood of 1 to 9) was diluted with a diluting water having a hardness of 100 ppm to a pulp concentration of 2.5%, and beater was added. And the beating degree was 380. Next, 1.2 liters of the obtained pulp slurry was weighed in a disintegrator and stirred to obtain light calcium carbonate (TP12).
1S (manufactured by Okutama Kogyo Co., Ltd.) was added to the pulp at 2%, and then vansulfate was added to the pulp at 1.5% and the amphoteric starch (Cato32).
10 (manufactured by Oji National Co., Ltd.) was added to pulp 0.6%, and then, as shown in Table 4 of the above Examples and Comparative Examples, Example 1 was used.
0.3% of pulp was added to each of the rosin emulsion compositions of 3 to 24 and Comparative Examples 8 to 13. Then pH
The obtained pulp slurry was diluted to a concentration of 0.25% with 7.5 dilution water, and then light calcium carbonate (TP121S (manufactured by Okutama Industry Co., Ltd.)) was added to the diluted pulp slurry with respect to 3% of pulp. ND talc (manufactured by Nippon Talc Co., Ltd.) to pulp 3%, NR12MLS as fixing agent
After adding 0.01% (made by Hymo Co.) to the pulp, the pulp slurry is circulated by a pump and dropped into a container from a height of 50 cm, and the area of bubbles accumulated on the liquid surface after 10 minutes. Was expressed as a percentage with respect to the entire liquid surface area. The obtained results are shown in Table 6.

(Hard Water Dilution Stability Test) The rosin emulsion compositions of the above Examples and Comparative Examples were diluted with hard water having a hardness of 300 ppm to a solid content of 5% and kept at 40 ° C. for 24 hours, and then filtered. After filtration, the residual filtration amount relative to the total solid content was measured and expressed as a percentage. The obtained results are shown in Table 5 (results using each sizing agent of Examples 1 to 12 and Comparative Examples 1 to 6) and Table 6 (each sizing agent of Examples 13 to 24 and Comparative Examples 8 to 13). Results).

[0061]

[Table 3]

[0062]

[Table 4]

[0063]

[Table 5]

[0064]

[Table 6]

[0065]

INDUSTRIAL APPLICABILITY According to the present invention, when a rosin-based substance is emulsified and dispersed, the state of dispersion is extremely fine as never before, and exhibits excellent dispersion stability as never before. It has low viscosity and is easy to handle, and in addition, it has not only excellent dispersion stability when diluted with hard water, but also
Foaming in the papermaking process is also lower than ever, and even in papermaking systems where the drying conditions are relatively mild in the pH range from acidic to neutral, conventional rosin emulsion compositions exhibit an excellent size effect. It is possible to provide a product, a paper sizing method using the same, and a paper excellent in sizing effect.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4L055 AG50 AG62 AG63 AG71 AG72                       AG89 AG97 AH11 AH12 AH33                       EA32 FA17 FA30

Claims (8)

[Claims] 1. A rosin emulsion composition containing a rosin substance (A) and a dispersant (B), wherein the dispersant (B) is a styrene monomer (a) and a (meth) acrylic acid ester monomer. A copolymer obtained by copolymerizing (b), a (meth) acrylamide-based monomer (c), and a monomer having the monomer (d) of (meth) acrylic acid and / or a salt thereof in the monomer structure, and / or a copolymer thereof. A rosin-based emulsion composition containing a neutralized product. 2. A (meth) acrylamide-based monomer (c)
The rosin-based emulsion composition according to claim 1, wherein the component is 5 to 30% by weight based on the total amount of the monomers (a) to (d). 3. The styrene monomer (a) component is 5 to 60.
% By weight, (meth) acrylic acid ester-based monomer (b)
The component is 5 to 60% by weight, the (meth) acrylamide-based monomer (c) component is 5 to 30% by weight, and the (meth) acrylic acid and / or its salt monomer (d) component is 5 to 30% by weight. Item 1. A rosin-based emulsion composition according to item 1. 4. A (meth) acrylic acid ester-based monomer (b) component is normal butyl acrylate, isobutyl acrylate, tert-butyl acrylate, 2-
The rosin-based emulsion composition according to any one of claims 1 to 3, which is ethylhexyl acrylate and 2-ethylhexyl methacrylate. 5. A (meth) acrylamide-based monomer (c)
The component is (meth) acrylamide.
The rosin-based emulsion composition according to any one of 1. 6. (a) to (d) are 2,4-diphenyl-
The rosin emulsion composition according to any one of claims 1 to 5, wherein the rosin emulsion composition is copolymerized in the presence of 4-methyl-1-pentene (e) and an alkyl mercaptan (f). 7. A method for sizing paper, which comprises adding the rosin emulsion composition according to claim 1 to a pulp slurry having a pH range of 4 to 8 to make a paper. 8. A rosin-based substance (A) and any one of claims 1 to 6.
A paper containing the copolymer according to any one of 1 to 3 and / or a neutralized product thereof.