JPH0124808B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a method for producing a non-aqueous resin dispersion liquid useful for paints, adhesives, toners for electrophotographic liquid developers, and the like. A polyhydric alcohol diacrylate such as diethylene glycol dimethacrylate and a polymerizable monomer such as lauryl acrylate are combined with toluene,
In aromatic hydrocarbon solvents such as benzene and xylene,
A method of producing a copolymer resin by carrying out a polymerization reaction in the presence of a polymerization initiator is known. The resins obtained in this way have been widely used for paints and adhesives. However, since aromatic hydrocarbon solvents are used in these resin (solution) manufacturing methods, crosslinking of the resin tends to proceed, resulting in problems such as gelation of the resin during the polymerization reaction and solidification of the resin during storage. It was hot. The same applies when this non-aqueous resin is used for paints or adhesives, and the adhesive strength decreases due to solidification during storage. In order to solve these problems, it has conventionally been necessary to suppress the amount of polyfunctional acrylic ester such as polyvalent glycol diacrylate to 3% by weight or less. Furthermore, even if the above problems are solved in this way, the resin is soluble in aromatic solvents and is therefore obtained in a dissolved state, so if it is used as is in a paint, the adsorption of the resin to the pigment may occur. Since the amount is small and the adhesive strength is insufficient, it is undesirable especially when used in electrodeposition coatings. Furthermore, the aromatic solvent used in this method is highly toxic and flammable, which not only poses problems in terms of environmental health, but also poses a risk of fire. The object of the present invention is to use an aliphatic solvent that is low in toxicity and flammability, has low solubility in the resulting resin, and is photochemically inert, so that it has excellent storage stability and does not reduce adhesive strength. Moreover, it is an object of the present invention to provide a method for producing a non-aqueous resin dispersion that causes fewer problems in terms of environmental hygiene and less risk of fire. That is, the method of the present invention comprises divinylben or an alkyl derivative thereof (having 1 to 20 carbon atoms) (hereinafter referred to as monomer A) in the presence of a polymerization initiator in a non-aqueous solvent containing an aliphatic hydrocarbon or its halide as a main component;
It is characterized by polymerizing a polar monomer (hereinafter referred to as monomer B) and a monomer (hereinafter referred to as monomer C) that solvates with the solvent both before and after polymerization. This polymerization reaction is carried out while heating the solvent to reflux. Through this reaction, a copolymer resin having a three-dimensional structure in which the monomer components are strongly crosslinked in a network-like manner is obtained. Monomer A has the property of being solvated with aliphatic solvents before polymerization, but not solvating after polymerization, and monomer B is used to control the charged polarity of the resin, and also to be used as a base for paints, etc. When the resin obtained by the method of the invention is used, it contributes to the dispersion stability of the colorant. Also, monomer C
is solvated in the solvent even after polymerization, resulting in excellent dispersion stability of the resin. The polymerization ratio of monomer A: monomer B: monomer C is 1 to 20:1.
A ratio of about 50:20 to 90 is appropriate. It is also possible to mix and polymerize a polymerizable monomer other than the above monomer components (hereinafter referred to as monomer D) up to 25 times the weight of monomer C component. Further, in the present invention, fine silica particles, wax or polyolefin having a softening point of about 60 to 130°C can be added to the resin manufacturing process. When fine silica particles are used, it is thought that the resin is obtained with the fine silica particles incorporated in its network structure.
In this case, the silica itself does not undergo physical changes such as dissolution during the reaction. In any case, in the case of silica, the dispersion stability can be further improved by making the specific gravity similar to that of the aliphatic hydrocarbon or its halide as the dispersion medium and by preventing gelation of the resin. On the other hand, when wax or polyolefin is used, these are dissolved in the reaction system by heating during the polymerization reaction, but after the reaction, they are precipitated into fine particles by cooling, and the resin is obtained in a state that is adsorbed to these fine particles. considered to be a thing. Here, wax or polyethylene has a specific gravity similar to that of the dispersion medium, prevents the resin from gelling, and has a molecular structure similar to that of the dispersion medium, so it not only helps improve dispersion stability, but also has a low softening point. It also helps improve adhesion. The appropriate amount of silica, wax or polyolefin added is about 5 to 50 parts by weight per 100 parts by weight of the resin. Next, the materials used in the present invention will be explained. The petroleum aliphatic hydrocarbons or halogenated aliphatic hydrocarbons used in the present invention include ligroin, n-hexane, n-pentane, n-heptane, n-octane, i-octane, i-dodecane, i- Nonane (commercially available products include Isopar H, G, L, K; Naphtha No. 6 manufactured by Exzon; and Ciel Sol manufactured by Shell Oil Co., Ltd.), carbon tetrachloride, perfluoroethylene, and the like. These aliphatic hydrocarbons or halogenated aliphatic hydrocarbons have a higher flash point than aromatic solvents such as benzene and toluene, and are also less toxic. Since the solubility of the resin of the present invention is lower than that of aromatic solvents, it has the advantage that gelation or solidification of the resin is unlikely to occur during the polymerization reaction or during storage. These petroleum-based aliphatic hydrocarbons or halogenated aliphatic hydrocarbons are solvents with high insulating properties (electrical resistance of 10 ¹⁰ Ω·cm or more) and low dielectric constants (dielectric constant of 3 or less). Further, aromatic solvents such as benzene and toluene may be added to these aliphatic solvents in small amounts. Examples of monomer A include o-divinylbenzene, m-divinylbenzene, p-divinylbenzene, p-methyldivinylbenzene, o-ethyldivinylbenzene, p-butyldivinylbenzene,
m-hexyldivinylbenzene, o-nonyldivinylbenzene, p-decyldivinylbenzene, o
-undecyldivinylbenzene, p-stearyldivinylbenzene, o-methyldivinylbenzene, p-ethyldivinylbenzene, o-butyldivinylbenzene, p-hexyldivinylbenzene, p-nonyldivinylbenzene, m-decyldivinylbenzene, p- Examples include undecyldivinylbenzene and o-stearyldivinylbenzene. Examples of monomer B are shown below. Examples of unsaturated carboxylic acids and their anhydrides include acrylic acid, methacrylic acid, itaconic acid, fumaric acid, maleic acid,
Examples include crotonic acid, aconitic acid, cinnamic acid, and anhydrides thereof. Examples of unsaturated nitrogen-containing compounds include vinylpyrrolidone, 2-vinylpyridine, 4-vinylpyridine, N-vinylpyridine, N-vinylimidazole, dimethylaminoethyl acrylate, dimethylaminoethyl methacrylate, and acrylic Examples of the alkyl ester (having 1 to 5 carbon atoms) of acid or methacrylic acid include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, propyl acrylate, propyl methacrylate, butyl acrylate, and butyl methacrylate. Further, typical examples of the unsaturated compound containing a glycidyl group include glycidyl acrylate and glycidyl methacrylate. Also, the C monomer has the general formula [Here, R is hydrogen or methyl group, A is -
COOCnH ₂ + ₁ or -OCOCnH ₂ n+ ₁ (where n is an integer from 6 to 20), respectively. ] Specific examples of the monomers are lauryl methacrylate, lauryl acrylate, stearyl methacrylate, stearyl acrylate, 2-ethylhexyl methacrylate, 2-ethylhexyl acrylate, dodecyl methacrylate, dodecyl acrylate, hexyl methacrylate, hexyl acrylate, and octyl acrylate. , octyl methacrylate, cetyl methacrylate, cetyl acrylate, vinyl laurate, vinyl stearate, etc. The polymerization initiators used when polymerizing these monomers A, B, and C include benzoyl peroxide, t-butyl perbenzoate, diamyl peroxide, di-t-butyl peroxide, lauryl peroxide, azobisiso Butyronitrile can be used. Other polymerizable monomers D include styrene,
Vinyl toluene, vinyl acetate, polyhydric alcohol dimethacrylate (e.g. ethylene glycol diacrylate, ethylene glycol dimethacrylate, diethylene glycol diacrylate, diethylene glycol methacrylate, triethylene glycol triacrylate, triethylene glycol trimethacrylate, butanediol diacrylate, butanediol) dimethacrylate, 1,6-hexanediol diacrylate,
1,6-hexanediol dimethacrylate, trimethylolpropane triacrylate, trimethylolpropane trimethacrylate, tetramethylolmethane triacrylate, tetramethylolmethane trimethacrylate, tetramethylolmethanetetraacrylate, tetramethylolmethanetetramethacrylate, dipropylene glycol diacrylate , dipropylene glycol dimethacrylate, trimethylolhexane triacrylate, trimethylolhexane trimethacrylate, pentaerythritate tetraacrylate, pentaerythritate tetramethacrylate, 1,3-butylene glycol diacrylate, 1,3-butylene glycol dimethacrylate, trimethyl methylolethane triacrylate, trimethylolethane methacrylate), and the like. Further, specific examples of commercially available waxes or polyolefins having a softening point of 60 to 130°C are as follows.

【table】

【table】

[Table] Examples are shown below.
Example 1 2.0 equipped with stirrer, thermometer and reflux condenser
Take 300g of isooctane in a four-necked flask,
Heated to 95°C. A solution consisting of 190 g of dodecyl methacrylate, 10 g of methacrylic acid, 10 g of p-butyldivinylbenzene and 6 g of azobisisobutyronitrile was added dropwise to this over 3 hours, and then
The mixture was further stirred at the above temperature for 4 hours to carry out a polymerization reaction, and a resin dispersion having a polymerization rate of 94.8% and a viscosity of 280 cp was obtained. The particle size of the resin was 0.05 to 0.10μ. Example 2 300 g of the resin dispersion obtained in Example 1 was mixed with 10 g of colloidal silica in a flask, heated at 100°C for 3 hours, and then cooled to give a viscosity of 318 cp and a particle size.
A resin dispersion containing colloidal silica of 0.10-0.20μ was obtained. Example 3 300 g of isododecane in the same flask as in Example 1.
was taken and heated to 90°C. Next, add 300g of lauryl methacrylate, 5g of N-vinylpyridine,
A solution consisting of 25 g of o-divinylbenzene and 3 g of benzoyl peroxide was added dropwise over 1.5 hours and stirred at the above temperature for 4 hours to carry out a polymerization reaction, resulting in a polymerization reaction of 96.5%, a viscosity of 280 cp, and a particle size of 0.05 to 0.20 μ. A resin dispersion was obtained. Example 4 300 g of the resin dispersion obtained in Example 3 was mixed with 20 g of bleached beeswax in a flask, stirred at 95°C for 22 hours, and then cooled to a viscosity of 215 cp and a particle size of 0.08 to 0.40 μ.
A beeswax-containing resin dispersion was obtained. Example 5 300g of Isopar G in the same flask as Example 1
and 30g of colloidal silica were taken and heated to 90°C. In this, 2-ethylhexyl methacrylate
150g, glycidyl methacrylate 15g, p-divinylbenzene 20g, methyl methacrylate 40g
After dropping a solution consisting of 6.3 g of lauroyl peroxide and stirring at the above temperature for 4 hours to carry out a polymerization reaction, the polymerization rate was 98.2% and the viscosity was 126 cp.
A resin dispersion with a particle size of 0.5 to 2.0 μm was obtained. Example 6 300g of Isopar L in the same flask as Example 1
and polyethylene (AC- manufactured by Allied Chemical Company)
6) Add 60g and heat to 95°C. Next, add 180 g of stearyl methacrylate, 40 g of lauryl methacrylate, 3 g of fumaric acid, 20 g of o-nonyldivinylbenzene, and 4 g of lauryl peroxide.
A polymerization reaction was carried out by adding dropwise a solution consisting of 30 g over 3 hours and stirring at the above temperature for 3 hours to obtain a resin dispersion having a polymerization rate of 95.4%, a viscosity of 128 cp, and a particle size of 0.3 to 0.5 .mu.m. Example 7 In the same flask as Example 1, 300 g of Isopar H,
180 g of cetyl methacrylate, 40 g of dodecyl acrylate, 15 g of p-divinylbenzene, 5 g of acrylic acid and 3 g of benzoyl peroxide were taken and stirred at 90°C for 6 hours to perform a polymerization reaction, with a polymerization rate of 96.4%.
A resin dispersion having a viscosity of 195 cp and a particle size of 0.15 to 0.92 μm was obtained. Examples 8 to 15 Table 2 was prepared in the same manner as in Example 7 except that the materials shown in Table 1 below and the reaction conditions shown in Table 2 below were used.
A resin dispersion having the properties shown below was prepared.

【table】

[Table] Example 16 In the same reactor as Example 1, 300 g of isooctane,
100 g of lauryl methacrylate, 50 g of o-divinylbenzene and 5 g of benzoyl peroxide were taken and polymerized by heating at 90°C for 10 hours. A solution consisting of 50 g of 2-ethylhexyl methacrylate, 10 g of glycidyl methacrylate and 1 g of benzoyl peroxide was then added to this polymer. In addition, the mixture was added dropwise at the above temperature for 2 hours, and then stirred at this temperature for 3 hours to carry out a further polymerization reaction, to obtain a resin dispersion having a polymerization rate of 94.0%, a viscosity of 980 cp, and a particle size of 0.03 to 0.10 μm. Example 17 The same method as Example 16 was used except that 2-ethylhexyl methacrylate was used instead of lauryl methacrylate and methacrylic acid was used instead of glycidyl methacrylate, but the viscosity was 1600 cp and the particle size was 0.05~.
A 0.1μ resin dispersion was obtained. The polymerization rate was 95.8%.

Claims (1)

[Scope of Claims] 1. (A) divinylbenzene or an alkyl derivative thereof (having 1 to 20 carbon atoms) in a nonaqueous solvent containing an aliphatic hydrocarbon or its halide in the presence of a polymerization initiator; (B) Unsaturated carboxylic acid, unsaturated carboxylic acid anhydride, unsaturated nitrogen-containing compound, glycidyl group-containing unsaturated compound, alkyl acrylate (carbon number 1
~5) A polar monomer consisting of an ester and/or an alkyl methacrylate (C1-5) ester, and (C) General formula [Here, R is hydrogen or methyl group, A is -
COOCnH ₂ n+ ₁ or -OCOCnH ₂ n+ ₁ (where n is an integer from 6 to 20), respectively. ] A method for producing a non-aqueous resin dispersion, which comprises subjecting the solvent and a monomer to be solvated to a polymerization reaction both before and after the polymerization.