JP2000248490A - Rosin-based emulsion sizing agent and sizing of paper using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a rosin-based emulsion sizing agent having excellent sizing effect and hot water resistance free from reduction in sizing performances in a wide range of pH 5-9, especially a papermaking range of high pH range. SOLUTION: This rosin-based emulsion sizing agent is obtained by dispersing a rosin ester (A) prepared by reacting an alkenyl-substituted succinic acid (a) with a rosin (b) and a polyhydric alcohol (c) in the presence of a metal oxide (d) as a catalyst under heating or a fortified rosin ester prepared by reacting the component (a) with the component b, the component c and an α,β-unsaturated carboxylic acid (e) in the presence of the metal oxide (d) as a catalyst under heating into water by using an emulsification dispersant (C).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a rosin emulsion sizing agent. More specifically, a rosin-based emulsion sizing agent comprising a rosin ester and a reinforced rosin mixed resin obtained by using a metal oxide as an esterification catalyst, or a rosin-based emulsion sizing agent comprising a reinforced rosin ester, and a paper sizing method using the same. 9 large area, especially high p
Even in the papermaking region of H, there is no decrease in size performance, and a good size effect and hot water sizing degree are exhibited.

[0002]

2. Description of the Related Art In the recent papermaking industry, the papermaking process has been closed in order to recover papermaking wastewater as much as possible from the viewpoint of strengthening regulations on factory wastewater and reducing the cost of water use. Papermaking conditions tend to be degraded due to an increase in dissolved electrolyte in the paper and an increase in papermaking temperature.In papermaking technology, calcium carbonate is generally used as a filler or coating pigment for paper, and calcium carbonate is added internally. In this case, the papermaking pH is necessarily 6 or more, and the pH is usually 5 or more for paper used as a coating pigment, damaged paper such as calcium carbonate internal paper, or recycled paper. It is.

Under these circumstances, aqueous dispersions of rosin or fortified rosin and saponified rosin-based sizing agents saponified with alkali such as caustic potash are not effective for sizing paper. Instead, a neutral sizing agent containing alkenyl-substituted succinic anhydride (ASA), alkyl ketene dimer (AKD) or the like as an active ingredient is used. However, the AKD-based sizing agent may cause slippage of the paper and a decrease in toner adhesiveness, and the use of the ASA-based sizing agent has not completely solved the problem of generation of stains in the papermaking process.

A rosin-based emulsion sizing agent which exerts a size effect even under the above-mentioned papermaking conditions has been proposed. For example, a sizing agent comprising a dispersant of a modified rosin obtained by esterifying a fortified rosin with a tertiary amino alcohol (JP-A-60-161472), a modification of a rosin or a fortified rosin reacted with a tri- to tetravalent alcohol Sizing agent consisting of rosin dispersant (Japanese Patent Publication No. 3-79480)
JP-B-6-4954), a sizing agent comprising a resin dispersion obtained by blending a rosin substance with a hydrocarbon resin, alkenyl succinic acids, etc. (JP-B-57-5420, JP-A-7-189173) )and so on. However, although the sizing agents disclosed in these publications exhibit a certain effect, the amount used must be increased in order to obtain a predetermined sizing effect as compared with ASA and AKD sizing agents. In addition, there is a problem that foaming in the paper making process and various stains also increase.

[0005] Recently, a rosin-based emulsion sizing agent having improved sizing effect, foaming property and stain trouble has been disclosed. For example, a sizing agent obtained by emulsifying and dispersing a rosin-based substance containing an ester of a rosin and a polyhydric alcohol with a cationic (meth) acrylamide-based polymer (Japanese Patent Laid-Open Publication No.
Japanese Patent Application Laid-Open No. 12-56993), a sizing agent obtained by emulsifying and dispersing a rosin-based substance with a (meth) acrylamide-based polymer (Japanese Patent Application Laid-Open No. 8-337997), and a rosin-based substance such as a rosin ester being styrene- (meth) acrylic acid-sulfonic acid. Sizing agent emulsified and dispersed with a copolymer (JP-A-7-1093)
No. 60), and a rosin-based emulsion sizing agent having a specific rosin ester which is effective even in a wider pH range of papermaking (Japanese Patent Application Laid-Open No. 10-156603, Japanese Patent Application No. 10-310994) has been proposed. There is a strong demand for a sizing agent that exhibits a further sizing effect.

[0006] Also, in papers requiring hot water resistance such as gypsum board base paper and cup base paper, among the conventional reinforced rosins, a reinforced rosin to which an α, β-unsaturated acid is relatively frequently added is replaced with caustic potash or the like. The saponified rosin sizing agent saponified with an alkali has been used in the acidic region. However, as described above, the deterioration of papermaking conditions or the necessity to partially use broke or waste paper containing calcium carbonate as a raw material pulp makes it difficult to maintain the papermaking pH in an acidic region, and these saponified types are used. Since it is no longer possible to obtain paper having sufficient hot water resistance with a rosin-based sizing agent, it is customary to use a rosin-based emulsion sizing agent as described above.

However, even with these rosin-based emulsion sizing agents, it is difficult to obtain a sufficient sizing effect and the degree of hot water sizing for increasing papermaking pH caused by closing or calcium carbonate. Esterification requires a long reaction time, which leads to an increase in production cost.

[0008]

SUMMARY OF THE INVENTION The present inventors have found that in the esterification of rosin, the reaction time can be greatly reduced, the production cost can be kept low, and a wide range of pH 5 to 9, particularly a high pH papermaking region. As a technical problem, a rosin-based emulsion sizing agent that imparts good sizing effect and hot water sizing degree to paper without a decrease in sizing performance and a method of sizing paper using the same have been studied as a technical problem. Has been completed.

[0009]

That is, the present invention relates to a method for heating alkenyl-substituted succinic acids (a), rosins (b) and polyhydric alcohols (c) in the presence of a metal oxide (d) as a catalyst. A rosin-based emulsion sizing agent obtained by dispersing a mixed resin of a rosin ester (A) and a reinforced rosin (B) obtained by a reaction in water using an emulsifying dispersant (C), or an alkenyl-substituted succinic acid (a ), A rosin (b), a polyhydric alcohol (c) and an α, β-unsaturated carboxylic acid (e) in the presence of a metal oxide (d) as a catalyst, and a heated rosin ester ( D)
Is dispersed in water using an emulsifying dispersant (C), and the rosin-based emulsion sizing agent is added to a pulp slurry in a wide range of pH 5 to 9, particularly a high pH paper-making region, to form a paper. This is a method for sizing paper that does not degrade the sizing performance and exhibits a good sizing effect and hot water sizing degree.

The alkenyl-substituted succinic acids (a) according to the present invention comprise an internal olefin having 6 to 36 carbon atoms, an ethylene oligomer, a propylene oligomer and a butylene oligomer, or a mixture thereof, and maleic anhydride and / or
Alternatively, it can be obtained by an addition reaction with maleic acid. Particularly preferred is an addition reaction product of a propylene tetramer having 12 to 16 unit numbers and / or a propylene pentamer with maleic anhydride.

The alkenyl-substituted succinic acids (a) can be produced by a conventional method, for example, by adding maleic anhydride and / or maleic acid to the olefins and reacting in an autoclave reactor at 150 to 250 ° C. for 20 to 24 hours. Can be

The rosins (b) according to the present invention include gum rosin, tall rosin, wood rosin, hydrogenated rosin,
Various rosins such as aldehyde-modified rosin and phenol-formalin resin-modified rosin can be mentioned, and these can be used alone or in combination of two or more.

The polyhydric alcohol (c) according to the present invention includes ethylene glycol, glycerin, pentaerythritol, propylene glycol, butanediol, hexanediol, trimethylolpropane, sorbitol and the like. The above can be used in combination.

The α, β-unsaturated carboxylic acids (e) used in the fortified rosin (B) or the fortified rosin ester (D) according to the present invention include fumaric acid, maleic acid, maleic anhydride, itaconic acid and citracone. Examples thereof include unsaturated dicarboxylic acids such as acid and citraconic anhydride, and unsaturated monocarboxylic acids such as acrylic acid and methacrylic acid. These may be used alone or in combination of two or more. Note that α, β-
The unsaturated carboxylic acids (e) are compared with the rosins (b)
It is 2 to 25% by weight, more preferably 5 to 17%. 2% by weight of the α, β-unsaturated carboxylic acid (e)
If it is less than 25%, the sizing effect in the low pH region is not excellent, and if it exceeds 25% by weight, the acid value becomes excessively large, adversely affecting the sizing effect, and both are not preferred.

In the rosin ester (A) or the fortified rosin ester (D) according to the present invention, the mixing ratio of the alkenyl-substituted succinic acids (a) and the rosins (b) is (a):
(B) = 0.5: 99.5 to 20:80 parts by weight, more preferably (a) :( b) = 1: 99 to 10:90 parts by weight, and the alkenyl-substituted succinic acids (a) and rosin The polyhydric alcohol (c) is obtained by a heating reaction at a charging ratio of 0.2 to 1.5, more preferably 0.4 to 1.0, with respect to the total carboxyl group equivalent of the class (b). When the blending ratio of the alkenyl-substituted succinic acids (a) is 0.5 parts by weight or less, the molecular weight becomes small, and
When the amount is more than 0 parts by weight, the molecular weight distribution becomes non-uniform, which adversely affects the size effect, and both are not preferred. When the hydroxyl equivalent of the polyhydric alcohol (c) is 0.2 or less with respect to the total carboxyl equivalent of the alkenyl-substituted succinic acids (a) and rosins (b), the molecular weight becomes small and the acid value becomes excessively large. If the ratio is 1.5 or more, unreacted polyhydric alcohol (c) remains, adversely affecting the size effect, and both are not preferred.

The metal oxide (d) as the catalyst according to the present invention includes various metal oxides such as zinc, calcium and magnesium. Of these, zinc oxide is preferred.

In the present invention, when the metal oxide (d) is used as an esterification catalyst, the esterification reaction time can be reduced with a small amount, the production cost can be reduced, and the rosin ester (A) or the enhanced rosin ester (D) can be used. The rosin-based emulsion sizing agent obtained using
Especially in the high pH papermaking area, the size performance does not decrease,
Good sizing effect and hot water sizing degree can be obtained. In general, esterification catalysts other than metal oxides include p-toluenesulfonic acid, metasulfonic acid, phosphoric acid, Lewis acids such as aluminum chloride, and acidic catalysts such as acetic acid.
These esterification catalysts also have the effect of shortening the esterification reaction time, but the rosin-based emulsion sizing agent
A reduction in size effect and hot water sizing degree is observed.

The amount of the metal oxide (d) used as the catalyst according to the present invention is 0.001 to 0.5% by weight, more preferably 0.01 to 0.5% by weight, based on the total weight of the rosins (b).
0.2% by weight. When the amount of the metal oxide (d) used is less than 0.001% by weight, the esterification reaction time is not shortened. When the amount exceeds 0.5% by weight, the unreacted metal oxide has a size effect. Adversely affect the use, and the significance of excessive use is not recognized.

The production of the rosin ester (A) according to the present invention may be carried out according to a conventional method. For example, alkenyl-substituted succinic acids (a), rosins (b) and polyhydric alcohols (c) are converted to metal oxides (d). 200-280 ° C in the presence of
For 10 to 24 hours.

The production of the fortified rosin (B) may be carried out according to a conventional method. For example, an α, β-unsaturated carboxylic acid (e) is reacted with the rosin (b) at 180 to 250 ° C. for 1 to 5 hours. Is obtained.

The compounding ratio of the rosin ester (A) and the fortified rosin (B) according to the present invention is (A) :( B) = 10: 9.
0 to 80:20 parts by weight, more preferably (A):
(B) = 30: 70-60: 40 parts by weight. When the mixing ratio of the rosin ester (A) is 10 parts by weight or less, a high pH
The size effect in the region is not excellent, and the case of 80 parts by weight or more is not preferable because the size effect in the low pH region is not excellent.

The production of the fortified rosin ester (D) according to the present invention may be carried out according to a conventional method. For example, an alkenyl-substituted succinic acid (a), a rosin (b) and a polyhydric alcohol (c) may be used as a catalyst. 2 in the presence of oxide (d)
After reacting by heating at 00 to 280 ° C. for 10 to 24 hours, α, β-unsaturated carboxylic acids (e) are added, and
You may make it react at 50 degreeC for 1-5 hours, and rosins (b)
Α, β-unsaturated carboxylic acids (e) to 180 to 250
After reacting at 1 ° C. for 1 to 5 hours, polyhydric alcohol (c)
And 200 in the presence of metal oxide (d) as a catalyst.
The reaction may be performed by heating at 280 ° C. for 10 to 24 hours, and alkenyl-substituted succinic acids (a), rosins (b), polyhydric alcohols (c) and α, β-unsaturated carboxylic acids (e) are simultaneously charged. , Metal oxide as catalyst (d)
May be reacted by heating at 200 to 280 ° C. for 10 to 24 hours.

[0023] Note that in addition to fortified rosin ester (D) rosin ester (A) within a range not to impair the effects of the present invention, C ₅ or more aliphatic petroleum resin obtained by polymerizing a residual olefins aromatic like May be used.

Examples of the emulsifying dispersant according to the present invention include various low molecular weight surfactants, high molecular emulsifying dispersants, casein,
Protective colloids such as polyvinyl alcohol and modified starch can be used, and these may be used alone or in combination of two or more.

Examples of various low molecular weight surfactants include alkali metal salts of fortified rosin, alkylbenzene sulfonates, polyoxyethylene alkyl phenyl ether sulfates, alkyl naphthalene sulfonates, and polyoxyethylene alkyl ether sulfosuccinate monoesters. , Polyoxyethylene alkyl phenyl ether sulfosuccinic acid monoester salts, anionic surfactants such as polyoxyethylene mono- and distyryl phenyl ether sulfosuccinic acid monoester salts, polyoxyethylene alkyl ether, polyoxyethylene alkyl phenyl ether, polyoxy Ethylene mono- and distyryl phenyl ether, propylene glycol fatty acid ester, fatty acid diethanolamide, polyoxypropylene polyoxyethylene Nonionic surface active agents such as glycol, and further can be illustrated tetraalkylammonium chlorides, trialkyl benzyl ammonium chloride, alkyl amines, cationic surfactants such as mono- and polyoxyethylene alkylamine. In addition, as the polymer emulsifying dispersant, a synthetic polymer having a hydrophobic group, a nonionic group or an ionic group or a general natural polymer emulsifying dispersant can be used. For example, an anionic or cationic emulsifying dispersant can be used. Partially or completely neutralized styrene- (meth) acrylic acid copolymer, anionic or cationic (meth) acrylic ester copolymer, or (meth) acrylamide copolymer, cationic Examples thereof include polyaminopolyamide-epichlorohydrin resin and poly (diallylamine) -epichlorohydrin resin. These polymeric emulsifying and dispersing agents may be used alone or as a protective colloid.
More than one species may be used in combination.

The method for producing the neutral sizing agent for papermaking according to the present invention is not particularly limited.
According to the method described in JP-B-36242, the mixed resin of the component (A) and the component (B) or the component (D) is dissolved in a solvent (for example, benzene, toluene, methylene chloride, or the like). After adding the component (C),
A method for producing an oil-in-water emulsion through a homogenizer (solvent method), and a mixed molten resin of the component (A) and the component (B) melted according to the method described in JP-A-54-77209. Or a method of adding the component (C) to the molten resin of the component (D) to form a water-in-oil emulsion, adding inverted water to cause a phase transition to an oil-in-water emulsion (phase inversion method), Japanese Patent Publication No. 53-3238
According to the method described in Japanese Patent Application Publication No. 0, after the component (C) is further mixed with the mixed resin of the component (A) and the component (B) or the component (D), (For example, 130 to 200 ° C, 150 to 1000 kg / c
m ² ), a method of producing an oil-in-water emulsion through a homogenizer (mechanical method) or the like is used.

The paper sizing method according to the present invention has a pH of 5
In the papermaking process of various papers and paperboards in the papermaking areas of Nos. To 9, the rosin-based emulsion sizing agent of the present invention is added to the pulp slurry in the wet end portion, for example, and is used in an amount of 0.01 to the absolute dry weight of the pulp. -5% by solid content, preferably 0.05-2% by weight.

Known fixing agents can be used as they are, for example, cationized starch, epichlorohydrin-modified polyamide polyamine resin, epichlorohydrin-modified dicyandiamide resin, epichlorohydrin-modified styrene-dimethylaminoethyl methacrylate copolymer, and polychlorinated polystyrene. Mannich-modified acrylamide, acrylamide-dimethylaminoethyl methacrylate copolymer, Hoffmann decomposed product of polyacrylamide, copolymer of dialkyldiallylammonium chloride and sulfur dioxide, and the like.

The filler that can be used in the paper sizing method according to the present invention is not particularly limited, and any known filler can be used. Further, calcium carbonate that cannot be used in the conventional acidic papermaking method can be used. Has the advantage that it can greatly contribute to the reduction of the papermaking price.

The rosin emulsion sizing agent according to the present invention has good sizing effect in the papermaking area such as use of waste paper containing calcium carbonate, increase in dissolved electrolyte due to closing, etc., increase in papermaking temperature, high pH, etc. Alkenyl-substituted succinic acids having two carboxyl groups (a), rosins (b), and rosin ester (A) with polyhydric alcohol (c) are partially polyester. Is presumed to have an esterified structure in the molecule, and by using zinc oxide as the esterification catalyst, the esterification reaction time is shortened, and at the same time, zinc oxide participates in the reaction in some form, and zinc oxide Has a higher molecular weight than rosin esters or rosin esters of rosins and polyhydric alcohols that do not use It is considered a factor in the optimal size to express the hot-water resistance size degree.

The rosin emulsion sizing agent according to the present invention can be used for printing paper such as high quality paper, medium quality paper, coated paper, PPC
It can be applied to information paper such as paper, foam paper, heat-sensitive paper, pressure-sensitive paper, packaging paper, cardboard base paper, white paperboard, and gypsum board paper. In addition to the production of cellulose fibers, when producing a mixture of cellulose fibers and mineral fibers, such as asbestos, rock wool, and synthetic fibers, such as polyamide, polyester, and polyolefin, to produce paper, paperboard, fiberboard, and the like. It can also be advantageously applied.

[0032]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention are as follows. Production of alkenyl-substituted succinic acids (a): A predetermined amount of an olefin oligomer and maleic anhydride are charged into an autoclave reactor, and heated at 150 to 250 ° C under a nitrogen stream.
After reacting for 0 to 24 hours, distillation under reduced pressure was performed to obtain an alkenyl-substituted succinic anhydride.

Production of rosin ester (A): stirrer,
About 18 in a reactor equipped with a thermometer, a distilling tube, and a nitrogen introducing tube
A predetermined amount of zinc oxide, a predetermined amount of the alkenyl-substituted succinic anhydride and a predetermined amount of glycerin are added to a predetermined amount of gum rosin in a molten state at 0 ° C., and the mixture is reacted at 200 to 280 ° C. for 10 to 24 hours under a nitrogen stream to obtain a rosin ester. I got

Production of fortified rosin (B): A prescribed amount of maleic anhydride is gradually added to a prescribed amount of gum rosin in a molten state at about 200 ° C. in a reactor equipped with a stirrer, a thermometer, and a nitrogen inlet tube. 1 to 5 at 180 to 250 ° C under nitrogen stream
An addition reaction was performed for a time to obtain a reinforced rosin (B).

Production of fortified rosin ester (D): a predetermined amount of zinc oxide to a predetermined amount of gum rosin in a molten state at about 180 ° C. in a reactor equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube. , A predetermined amount of the alkenyl-substituted succinic anhydride and glycerin are added, and the mixture is added under a nitrogen stream at 200 to 280.
C. for 10 to 24 hours, then a predetermined amount of maleic anhydride was gradually added, and addition reaction was performed at 180 to 250.degree. C. for 1 to 5 hours to obtain a reinforced rosin ester (D).

Production of rosin emulsion sizing agent:
A predetermined amount of the mixed resin of the rosin ester (A) and the reinforced rosin (B) obtained here or the reinforced rosin ester (D) is heated and dissolved at about 150 ° C., and the emulsifying dispersant (C ) Is added and mixed to form a water-in-oil emulsion, and a predetermined amount of hot water is quickly added thereto to form a stable oil-in-water emulsion. After cooling to room temperature, a rosin emulsion sizing agent is added. Obtained.

Performance evaluation of rosin-based emulsion sizing agent: (1) Stekigt sizing test 2.5% pulp slurry (L-BKP, CSF38)
0 ml), the cationized starch was 0.5% in terms of solids with respect to the absolutely dry pulp, and the aluminum sulfate was 0.5% in terms of solids with respect to the absolutely dry pulp. 0.4% in terms of solid content based on absolutely dry pulp, and 10% of light calcium carbonate as solids based on absolutely dried pulp, and water is added to reduce the pulp concentration to 1%.
And then add bentonite to the absolutely dried pulp at 0.04% in terms of solids content, and add TAPPI according to a conventional method.
Paper was made with a standard sheet machine. At this time, the pH of the pulp slurry was 8.0. Next, 3.5kg /
Press with cm ² and drum dryer (surface temperature 90 ° C)
For 1 minute to prepare a hand-made paper. This hand-made paper had a basis weight of 60 g / m ² . The hand-made paper thus obtained was conditioned at a temperature of 20 ° C. and a humidity of 65% for 24 hours, and then the size effect of each paper was measured by the JIS P8112 Steicht method.

(2) Hot water sizing test: concentration 2.5
% Pulp slurry (newspaper waste / leaflet wastepaper = 7/3, C
SF200ml) and aluminum sulfate 6%
% (Slurry pH 5) and 4% (slurry pH 6), and a rosin-based emulsion sizing agent was added to the absolutely dry pulp at 1.0% in terms of solid content and mixed well to obtain a pulp slurry for papermaking. . Water of the same pH value was added to this pulp slurry to dilute it to a pulp concentration of 1%.
12 (trade name, manufactured by Seiko Chemical Co., Ltd .: cationic acrylamide-based polymer, concentration: 10%) was added at 0.1% to the absolutely dry pulp, and paper was made using a TAPPI standard sheet machine according to a conventional method. 3.5 kg / cm ²
And press with a drum dryer (surface temperature 90 ° C).
After drying for a minute, a hand-made paper was prepared. The handmade paper had a basis weight of 65 g / m ² . After the hand-made paper thus obtained was conditioned at a temperature of 20 ° C. and a humidity of 65% for 24 hours, each paper was floated on hot water of 80 ° C., and the time required until 1/5 of the surface area became wet (heat-resistant water-resistant size). Degree) was measured.

[0039]

EXAMPLES Hereinafter, the present invention will be described specifically with reference to Production Examples, Examples, and Comparative Examples, but the present invention is not limited to these Examples. In addition, in each example, all parts and% are based on weight unless otherwise specified.

Production of alkenyl-substituted succinic acids (a): [Production Example a-1] A high mass polymer (trade name, manufactured by Nippon Oil Co., Ltd .: propylene oligomer) was placed in an autoclave reactor.
After 144 parts of carbon number 15) and 68 parts of maleic anhydride were charged and reacted at 200 ° C. for 24 hours under a nitrogen stream, vacuum distillation was carried out to obtain an alkenyl-substituted succinic anhydride having an acid value of 230.

Production of rosin ester (A): [Production Example A-1] 800 parts of gum rosin in a molten state at 180 ° C. in a reactor equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube. 0.01 parts of zinc oxide, 13 parts of alkenyl-substituted succinic anhydride obtained in Production Example a-1, glycerin 8
6 parts were charged and reacted at 245 to 250 ° C. for 15 hours under a nitrogen stream to obtain a rosin ester (A) having an acid value of 12.9. The properties are shown in Table 1.

[Production Examples A-2 to 8] In Production Example A-1, the amounts of alkenyl-substituted succinic acids (a), rosins (b), polyhydric alcohols (c), and metal oxides (d) were measured. Except that the type was changed as shown in Table 1, Production Example A-
In the same manner as in Example 1, rosin esters of Production Examples A-2 to A-8 were obtained. The properties are shown in Table 1.

Production of Comparative Rosin Ester (CA) [Comparative Production Examples CA-1 to 8] In Production Example A-1, alkenyl-substituted succinic acids (a), rosins (b), polyhydric alcohols (c) Comparative Production Examples CA-1 to 8 in the same manner as in Production Example A-1, except that the charged amount and type of the esterification catalyst were changed as shown in Table 2.
A rosin ester (A) was obtained. The properties are shown in Table 2.

Production of fortified rosin ester (D): [Production Example D-1] 800 parts of gum rosin in a molten state at about 180 ° C. in a reactor equipped with a stirrer, a thermometer, a distilling tube, and a nitrogen introducing tube. 0.1 part of zinc oxide, 13 parts of the alkenyl-substituted succinic acids (a) obtained in Production Example a-1 and 42 parts of glycerin are added, and the mixture is added at a temperature of 240 to 250 ° C. under a nitrogen stream.
After reacting for 80 hours, 80 parts of maleic anhydride was gradually added, followed by an addition reaction at 180 to 250 ° C. for 3 hours.
Thus, 1 fortified rosin ester (D) was obtained. Table 1 shows the properties.
Shown in

[Production Example D-2] In Production Example D-1, alkenyl-substituted succinic acids (a), rosins (b), polyhydric alcohols (c), α, β-unsaturated carboxylic acids (e)
In the same manner as in Production Example D-1, except that the charged amount and the type of the esterification catalyst metal oxide (d) were changed as shown in Table 1, a reinforced rosin ester (D) of Production Example D-2 was obtained. .
The properties are shown in Table 1.

[0046]

[Table 1] * α, β-UR: α, β-unsaturated carboxylic acids * MR: maleic anhydride * ASA: alkenyl-substituted succinic acids * ZnO: zinc oxide * MgO: magnesium oxide * CaO: calcium oxide * Z-100S: Coropearl Z -100S (trade name); manufactured by Seiko Chemical Co., Ltd .; alkenyl-substituted succinic anhydride; concentration 100%

Production of Comparatively Enhanced Rosin Ester (CD) [Comparative Production Example CD-1] In Production Example D-1, alkenyl-substituted succinic acids (a), rosins (b), polyhydric alcohols (c), Comparative Production Example CD- was prepared in the same manner as in Production Example D-1, except that the charged amounts and types of the α, β-unsaturated carboxylic acids (e) and the esterification catalyst (d) were changed as shown in Table 2.
Thus, 1 fortified rosin ester (D) was obtained. Table 2 shows the properties.
Shown in

[0048]

[Table 2] * α, β-UR: α, β-unsaturated carboxylic acids * MR: maleic anhydride * ASA: alkenyl-substituted succinic acids * CH ₃ COONa: sodium acetate * ZnO: zinc oxide * MgO: magnesium oxide * PTS: paratoluene Sulfonic acid * CaO: Calcium oxide * Ca (OH) ₂ : Calcium hydroxide * KOH: Potassium hydroxide * Z-100S: Coropearl Z-100S (trade name); manufactured by Seiko Chemical Co., Ltd .; Alkenyl-substituted succinic anhydride ; Concentration 100%

Production of fortified rosin (B): [Production Example B-1] 800 parts of gum rosin in a molten state at 180 ° C. in a reactor equipped with a stirrer, a thermometer and a nitrogen inlet tube, and 80 parts of maleic anhydride Slowly and add 2 under a stream of nitrogen.
An addition reaction was performed at 00 ° C. for 5 hours to obtain a reinforced rosin (B) having an acid value of 230.

[Production Example B-2] A reinforced rosin (B) having an acid value of 242 was obtained in the same manner as in Production Example B-1, except that 100 parts of maleic anhydride was used.

Production of rosin emulsion sizing agent: [Example 1] A mixed resin of 30 parts of rosin ester (A) of Production Example A-1 and 70 parts of reinforced rosin (B) of Production Example B-1 was mixed for about 150 hours. The mixture was heated and melted at 0 ° C. and mixed vigorously with 45 parts of an emulsifying dispersant RX-1 (trade name, manufactured by Seiko Chemical Co., Ltd .: anionic styrene acrylic copolymer: concentration: 20%), and mixed. A water-in-water emulsion was obtained, and 93 parts of hot water were quickly added thereto to form a stable oil-in-water emulsion, and then cooled to room temperature to obtain a rosin-based emulsion sizing agent. The properties are shown in Table 3.

[Examples 2 to 10] Table 3 shows the compounding ratios and types of the rosin ester (A) and the reinforced rosin (B) or the reinforced rosin ester (D) and the emulsifying dispersant (C) in Example 1. Rosin emulsion sizing agents of Examples 2 to 10 were obtained in the same manner as in Example 1 except that The properties are shown in Table 3.

[0053]

[Table 3] * RX-1: (trade name, manufactured by Seiko Chemical Co., Ltd .: emulsifying dispersant (C); anionic styrene acrylic copolymer: concentration 20%)

Production of comparative rosin-based emulsion sizing agent: [Comparative Examples 1 to 9] Same as Example 1 except that the amount and type of the dispersant resin composition used in Example 1 were changed as shown in Table 4. Emulsification and dispersion were carried out by the method to obtain each rosin-based emulsion sizing agent. Table 4 shows the properties.

[0055]

[Table 4] * RX-1: (trade name, manufactured by Seiko Chemical Co., Ltd .: emulsifying dispersant (C); anionic styrene acrylic copolymer: concentration 20%) * Reference example: Coropearl S-80 (trade name, starlight (Saponified rosin sizing agent manufactured by Chemical Industry Co., Ltd .: 50% concentration)

[Evaluation of Performance of Rosin Emulsion Sizing Agent] The size effect and hot water sizing degree of the rosin emulsion sizing agents shown in Examples 1 to 10 and Comparative Examples 1 to 9 were measured in accordance with the above embodiment. Performance evaluation was performed. Table 5 shows the effect.

[0057]

[Table 5]

[0058]

As described in Examples, the rosin emulsion sizing agent of the present invention comprises a mixed resin of rosin ester and reinforced rosin obtained by using a metal oxide as an esterification catalyst, or reinforced rosin ester. A rosin-based emulsion sizing agent and a paper sizing method using the same. The use of a metal oxide as an esterification catalyst can greatly reduce the reaction time in a small amount, keep production costs low, and have a wide pH 5 to 9 range. In particular, even in a high pH papermaking region, there is no decrease in sizing performance, and a good sizing effect and hot water sizing degree are exhibited.

Claims (5)

[Claims] 1. A rosin ester (A) obtained by heating and reacting an alkenyl-substituted succinic acid (a), a rosin (b) and a polyhydric alcohol (c) in the presence of a metal oxide (d) as a catalyst. A rosin-based emulsion sizing agent characterized in that a mixed resin of rosin and reinforced rosin (B) is dispersed in water using an emulsifying dispersant (C). 2. In the presence of a metal oxide (d) catalyzed by alkenyl-substituted succinic acids (a), rosins (b), polyhydric alcohols (c) and α, β-unsaturated carboxylic acids (e). A rosin-based emulsion sizing agent obtained by dispersing a strengthened rosin ester (D) obtained by heat-reacting in water using an emulsifying dispersant (C) in water. 3. The rosin emulsion sizing agent according to claim 1, wherein the metal oxide (d) as a catalyst is used in an amount of 0.001 to 0.5% by weight based on the rosin (b). . 4. The rosin emulsion sizing agent according to claim 1, wherein the metal oxide (d) as a catalyst is zinc oxide. 5. A paper sizing method comprising adding the rosin emulsion sizing agent according to any one of claims 1 to 4 to a pulp slurry for papermaking.