JPH0741525A - Modified amino resin and water-based resin composition containing the same - Google Patents

Abstract

PURPOSE:To improve the affinity of an amino resin for water. CONSTITUTION:The modified amino resin is one obtained by reacting an amino resin with ethylenic compounds comprising an ethylenic compound having a hydroxyl group and/or an amide group and at least either of an ethylenic carboxylic acid and an ethylenic carboxylic anhydride in the presence of an organic peroxide. The water-based resin composition contains this modified amino resin as a cross-linking agent. The objective resin and composition have each an excellent affinity for water, and are exceedingly useful as a binder in various industrial applications including a water-based coating composition, water-based ink, adhesive, and sealing agent.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a novel and useful amino resin modified product and an aqueous resin composition containing the same. Amino resin modified product of the present invention and an aqueous resin composition containing the same, for water-based inks, including for aqueous coatings,
It can be used in a wide variety of applications such as for adhesives and sealing agents.

[0002]

2. Description of the Related Art In recent years, from the viewpoints of environmental protection and harmfulness to the human body, it has been required to reduce the amount of organic solvent discharged during the coating process, and water-based coatings have been promoted. Methyl etherified melamine, methyl etherified benzoguanamine and the like are used as cross-linking agents in water-based paints.
However, this type of cross-linking agent volatilizes during baking of the paint and causes fumes. Therefore, a water-dispersed oily amino resin with an aqueous acrylic resin or the like has been investigated as a crosslinking agent, but since the amino resin has a low affinity for water, the compatibility with the aqueous acrylic resin is poor, There is a problem that it is difficult to obtain a product having excellent separation stability.

[0003]

Therefore, as a result of diligent studies to improve the affinity of amino resins for water, the present inventor has found that ethylenically unsaturated carboxylic acid and / or ethylenic unsaturated carboxylic acid in the presence of an organic peroxide. It is possible to synthesize an amino resin modified product having greatly improved affinity for water by reacting an unsaturated carboxylic acid anhydride and an ethylenically unsaturated compound containing an ethylenically unsaturated compound having a hydroxyl group and / or an amide group with an amino resin. The present invention has been completed and the present invention has been achieved. The amino resin modified product of the present invention, when used as a thermosetting component in an aqueous paint,
Little fumes are generated during baking, and has excellent affinity for water.

[0004]

The present invention provides an amino resin having an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic acid anhydride and a hydroxyl group and / or an amide group in the presence of an organic peroxide. Provided are an amino resin modified product obtained by reacting an ethylenically unsaturated compound containing an ethylenically unsaturated compound, and an aqueous resin composition containing the amino resin modified product as a crosslinking agent.

In the presence of organic peroxides, unsaturated compounds form radical addition polymers. At this time, a graft reaction of the ethylenically unsaturated carboxylic acid and / or the ethylenically unsaturated carboxylic acid anhydride to the amino resin occurs by the radical abstraction reaction of the organic peroxide. Although the grafting point of the amino resin is not always clear, it is presumed that the amino resin is grafted by the abstraction reaction of the methylene group of the methylol derivative of the amino resin with the radical of the organic peroxide. As a result of the grafting reaction, a carboxyl group is directly introduced into the amino resin, and an amino resin-modified product having an improved affinity for water can be obtained. further,
Condensation of the polymer to the amino resin by the reaction of the ethylenically unsaturated compound having a hydroxyl group and / or an amide group and / or the hydroxyl group and / or the amide group in the produced polymer with the amino resin simultaneously proceeds.

The amino resin is methylolated by the reaction of formaldehyde with an amino compound such as urea, melamine, benzoguanamine and spiroguanamine, and then
It is obtained by etherification by dehydration condensation with alcohols. Typical examples of the ethylenically unsaturated carboxylic acid include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, glutaconic acid and tetrahydrophthalic acid. Representative examples of the ethylenically unsaturated carboxylic acid anhydride include maleic anhydride, itaconic anhydride, glutaconic anhydride, tetrahydrophthalic anhydride and the like. The ethylenically unsaturated carboxylic acid and / or ethylenically unsaturated carboxylic acid anhydride is preferably used in the ethylenically unsaturated compound in an amount of 50 to 95% by weight, more preferably 70 to 95% by weight.

Typical examples of the ethylenically unsaturated compound having a hydroxyl group include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, N-methylolacrylamide, ethylene glycol mono (meth) acrylate, Examples include diethylene glycol mono (meth) acrylate. Typical examples of the ethylenically unsaturated compound having an amide group include acrylamide and methacrylamide.

The ethylenically unsaturated compound having a hydroxyl group and / or an amide group is used in the ethylenically unsaturated compound in an amount of preferably 5 to 50% by weight, more preferably 5 to 30% by weight. Furthermore, if necessary, other ethylenically unsaturated compounds can be used in combination. Representative examples include alkyl (meth) acrylate, styrene, vinyltoluene, (meth) acrylonitrile, vinyl acetate and the like. The ethylenically unsaturated compound is preferably used in an amount of 3 to 50% by weight based on the total solid content.

Typical organic peroxides are benzoyl peroxide, cumene hydroperoxide, t-butyl hydroperoxide, diisopropyl peroxycarbonate, dit-butyl peroxide, t-butyl peroxybenzoate and the like. Is mentioned. The organic peroxide is preferably used in an amount of 10 to 100 parts by weight based on 100 parts by weight of the ethylenically unsaturated compound. The reaction of the above ethylenically unsaturated compound with an amino resin in the presence of an organic peroxide is 70 to 120 under an inert gas stream.
It is performed at 2 ° C. for 2 to 6 hours. It is desirable to gradually drop the organic peroxide into the system.

The modified amino resin obtained after the reaction is neutralized by the action of ammonia and amines to be water-soluble or water-dispersed. Representative amines include monoethanolamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, dipropylamine, isopropylamine, diisopropylamine, triethanolamine, butylamine, dibutylamine, ethylhexylamine, ethylenediamine,
Examples include propylenediamine, methylethanolamine, dimethylethanolamine, diethylethanolamine, morpholine, and the like, with dimethylethanolamine being particularly preferred.

The amino resin modified product of the present invention can be used alone as a binder for water-based paints, water-based inks, adhesives, sealing agents, etc. It can also be used as a resin composition. As other water-based resin, for example, water-based acrylic resin, water-based epoxy resin, water-based polyester resin, water-based urethane resin, and the like,
It is used in an amount of 3 to 95% by weight based on the total solid content. The aqueous resin composition of the present invention, if necessary, dyes for coloring and the like, various additives for improving the physical properties of the cured product, such as fillers, leveling agents, curing agents, flame retardants, thickening agents. Agents, water-soluble organic solvents, slipperiness-imparting agents and the like can be contained.

[0012]

EXAMPLES The present invention will be specifically described below with reference to examples. In the examples, "part" means "part by weight" and "%" means "% by weight". [Example 1] A separable four-necked flask was equipped with a temperature control regulator, a cooling tube, and a stirrer, and charged with 514 parts of partially butyl etherified benzoguanamine resin ("Cymel 1128" manufactured by Mitsui Cyanamid Co., Ltd., solid content 70%),
After raising the temperature to about 90 ° C and replacing the inside of the reaction vessel with nitrogen, 32 parts of acrylic acid and 2-hydroxyethyl methacrylate were added from a dropping pipe.
8 parts, organic peroxide ("Perbutyl O" manufactured by NOF Corporation)
12 parts was added dropwise over 1 hour. After the dropping was completed, the reaction was continued for another 1 hour to obtain a modified amino resin having a solid content of 66.0%. To 75.8 parts of the obtained modified amino resin, 4.9 parts of dimethylaminoethanol and 19.3 parts of water were added with sufficient stirring.

Example 2 A reactor similar to that of Example 1 was charged with 400 parts of partially butyl etherified benzoguanamine resin "Cymel 1128", the temperature was raised to about 90 ° C to replace the inside of the reaction vessel with nitrogen, and then a dropping pipe was added. More acrylic acid 60 parts, acrylamide 4 parts, 2-hydroxyethyl methacrylate 20
Parts, ethyl acrylate 36 parts, and organic peroxide "Perbutyl O" 24 parts were added dropwise over 1 hour. After the dropping was completed, the reaction was continued for another 1 hour to obtain a modified amino resin having a solid content of 81.3%. To 61.5 parts of the obtained modified amino resin, 9.3 parts of dimethylaminoethanol and 29.2 parts of water were added with sufficient stirring.

Example 3 A reactor similar to that of Example 1 was charged with 435 parts of methyl etherified benzoguanamine resin (“Melan 553” manufactured by Hitachi Chemical Co., Ltd., solid content 85%), and about 90
After the temperature was raised to ℃ and the inside of the reaction vessel was replaced with nitrogen, 24 parts of acrylic acid and 2-hydroxyethyl methacrylate
Parts, and 6 parts of the organic peroxide "Perbutyl O" were added dropwise over 1 hour. After the dropping was completed, the reaction was continued for another hour to obtain an amino resin modified product having a solid content of 78.8%. 50.8 parts of the obtained modified amino resin, 33.3 parts of water-soluble acrylic resin (triethylamine neutralized product of "John Cryl 587" manufactured by Johnson Polymer Co., solid content 30%), dimethylaminoethanol
3.0 parts and 12.9 parts of water were added with thorough stirring.

Comparative Example 1 A reactor similar to that of Example 1 was charged with 514 parts of partially butyl etherified benzoguanamine resin “Cymel 1128”, heated to about 90 ° C. and the inside of the reaction vessel was replaced with nitrogen, and then a dropping pipe was added. Then, 32 parts of acrylic acid, 8 parts of 2-hydroxyethyl methacrylate and 12 parts of 2,2'-azobisisobutyronitrile were added dropwise over 1 hour. After the dropping was completed, the reaction was continued for another 1 hour to obtain a modified amino resin having a solid content of 65.2%. To the obtained amino resin modified product 76.7 parts,
Dimethylaminoethanol (4.9 parts) and water (18.4 parts) were added with sufficient stirring.

Comparative Example 2 37.1 parts of a water-soluble acrylic resin (triethylamine neutralized product of "John Cryl 587" manufactured by Johnson Polymer Co., solid content 30%) was added to 47.1 parts of methyl etherified benzoguanamine resin "Melan 553" and water 19.6. Parts were added with thorough stirring. Appearance and 50 ° C. of the aqueous resin compositions obtained in Examples 1 to 3 and Comparative Examples 1 and 2
Table 1 shows the results of evaluation of stability after storage for a week.

[0017]

[Table 1]

[0018]

Industrial Applicability The amino resin modified product of the present invention and the aqueous resin composition containing the same have excellent affinity to water and are widely used as binders for water-based paints, water-based inks, adhesives and sealing agents. Can be used for purposes,
It is extremely useful industrially.

Claims (5)

[Claims] 1. An amino resin in the presence of an organic peroxide,
An amino resin modified product characterized by reacting an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic acid anhydride and an ethylenically unsaturated compound containing an ethylenically unsaturated compound having a hydroxyl group and / or an amide group . 2. An ethylenically unsaturated compound is contained in the total solid content,
The modified amino resin according to claim 1, which is 3 to 50% by weight. 3. The ethylenically unsaturated carboxylic acid and / or ethylenically unsaturated carboxylic acid anhydride is 50 to 95% by weight in the ethylenically unsaturated compound, and has a hydroxyl group and / or an amide group. The amino resin modified product according to claim 1 or 2, wherein the content of the body is 5 to 50% by weight in the ethylenically unsaturated compound. 4. The organic peroxide is an ethylenically unsaturated compound.
The modified amino resin according to claim 1, which is 10 to 100 parts by weight with respect to 100 parts by weight. 5. An aqueous resin composition comprising the amino resin modified product according to claim 1 as a crosslinking agent.