JPH10265551A - Resin composition, water-based resin composition, its use, and their production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject composition affording such a water-based resin composition as to be easy to run to a water-based form and give a cured film with high adhesiveness to a material and durability and low in fume generation under coat baking process, by polymerizing specific ethylenically unsaturated monomer(s) in the presence of an amino resin and epoxy resin. SOLUTION: This composition is obtained by polymerizing (C) ethylenically unsaturated monomer(s) including an ethylenically unsaturated carboxylic acid (e.g. acrylic acid) and/or ethylenically unsaturated carboxylic acid anhydride (e.g. maleic anhydride) in the presence of (A) an amino resin and (B) an epoxy resin to effect chemically binding the component A to part of the polymer from the component C and the component B to part of the polymer from the component C. Preferably the amounts of the components A, B and C to be used are 10-89 wt.%, 1-50 wt.% and 10-89 wt.% based on the whole solid content of this composition, respectively. Preferably a hydroxyl or alkoxymethyl-bearing ethylenically unsaturated monomer is included in the component C.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to various paints,
The present invention relates to a resin composition, an aqueous resin composition, and a method for producing the same, which can be used for a wide range of uses such as an aqueous ink, an adhesive and a sealing agent.

[0002]

2. Description of the Related Art Conventional baking paints are mainly of a solvent type, and an organic solvent is discharged during a coating process. In recent years, a reduction in the amount of organic solvent discharged has been required from the viewpoint of environmental protection and energy saving. Water-based paints are being promoted.
As the aqueous baking paint, many compositions such as aqueous acrylic resin and aqueous polyester resin containing an amino resin such as methyl etherified melamine and methyl etherified benzoguanamine as a cross-linking agent have been studied. However,
These amino resins used as a cross-linking agent are volatilized at the time of baking paint and cause fumes that contaminate the inside of the oven. For this reason, use of an amino resin having a low content of low molecular weight, which may cause fume, has been attempted, but there has been a problem that the coating material is separated due to low water solubility.

Further, epoxy resins are often used as resins for water-based paints in order to impart adhesiveness to substrates, chemical resistance and the like. In particular, it is known that a modified epoxy resin obtained by modifying a glycidyl group with a secondary amine or phosphoric acid or the like and then neutralizing with a suitable counter ion to make it water-soluble is effective in improving the adhesion to metals and the like. ing. However, when these modified epoxy resins are used, there are problems in storage stability of the paint, coloring of the resin solution, and the like.

[0004]

DISCLOSURE OF THE INVENTION The present invention can easily be made water-soluble, has good substrate adhesion, durability, etc., in its cured film, and reduces the amount of fume generated during the baking process. A resin composition giving a small aqueous resin composition,
It is an object of the present invention to provide an aqueous resin composition obtained by making the resin composition aqueous, and a method for producing the same.

[0005]

The present inventors have developed an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic anhydride in the presence of an amino resin and an epoxy resin. The resin composition obtained by polymerizing the body can be easily made water-based, and the obtained water-based resin composition has excellent separation stability and adhesion to metals and the like, and furthermore, a small amount of fume is generated during the paint baking step. And found the present invention. Although the details of the resin composition of the present invention are unknown, due to partial chemical bond generation during the reaction, the amino resin and a part of the polymer of the ethylenically unsaturated monomer are chemically bonded, It is considered that a part of the polymer of the epoxy resin and the ethylenically unsaturated monomer is chemically bonded, and physical chain entanglement occurs at a molecular level. As a result, it is inferred that compatibility was improved.

That is, the present invention comprises polymerizing an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic anhydride in the presence of an amino resin and an epoxy resin. That the amino resin and a part of the polymer of the ethylenically unsaturated monomer are chemically bonded, and that the epoxy resin and the part of the polymer of the ethylenically unsaturated monomer are chemically bonded. The present invention relates to a characteristic resin composition. Further, the present invention provides the above resin composition,
The present invention relates to an aqueous resin composition which is dissolved or dispersed in an aqueous medium in the presence of a basic substance. The present invention also relates to an aqueous paint containing the aqueous resin composition as a binder.

Further, the present invention is to radically polymerize an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic anhydride in a solution containing an amino resin and an epoxy resin. And a method for producing a resin composition. Further, the present invention, in a solution containing an amino resin and an epoxy resin,
After radical polymerization of an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic acid anhydride to prepare a resin composition, a basic substance and an aqueous medium are added, The present invention relates to a method for producing an aqueous resin composition, comprising dissolving or dispersing the resin composition in an aqueous medium.

[0008] The amino resin is obtained by reacting an amino compound such as urea, melamine, benzoguanamine, spiroguanamine and the like with methylaldehyde to form a methylol and then etherifying it by dehydration condensation with an alcohol. Although the degree of methylolation, the degree of condensation and the like can be used arbitrarily selected amino resins, the properties of the coating film when the aqueous resin composition of the present invention is used as a binder for paint, and the stability of the aqueous resin composition over time can be used. In terms of gender and price,
An amino resin in which the amino compound is benzoguanamine is preferably used. The amino resin is preferably contained in a range of 10 to 89% by weight based on the total solid content of the resin composition. If the content of the amino resin is less than 10% by weight, the thermosetting property cannot be sufficiently exhibited, and if it exceeds 89% by weight, the crosslinking density is too high, and it is difficult to satisfy the required coating film properties.

The epoxy resin is not particularly limited.
For example, glycidyl ether epoxy resins such as bisphenol A epoxy resin, bisphenol F epoxy resin, bisphenol S epoxy resin, and novolak epoxy resin and modified products thereof can be used, but in consideration of availability, Epoxy equivalent is 150
To 30,000 are preferably used. The epoxy resin is appropriately selected and used depending on the required functional group density, softening temperature, solubility, compatibility and the like. A commercially available epoxy resin can be used as it is, and it can be used alone or as a mixture of two or more kinds. Epoxy resin, based on the total solids of the resin composition,
It is preferably contained in the range of 1 to 50% by weight. When the content of the epoxy resin is less than 1% by weight, effects such as adhesion to a substrate are hardly exhibited, and when the content exceeds 50% by weight, three-dimensionalization tends to occur during the reaction, which is not preferable.

[0010] The resin composition of the present invention is obtained by subjecting an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic anhydride to a radical in a solution containing an amino resin and an epoxy resin. Obtained by polymerization. Representative examples of the ethylenically unsaturated carboxylic acids include acrylic acid, methacrylic acid, itaconic acid, maleic acid, fumaric acid, glutaconic acid, tetrahydrophthalic acid, and the like. Representative examples of the ethylenically unsaturated carboxylic anhydride include maleic anhydride, itaconic anhydride, glutaconic anhydride, tetrahydrophthalic anhydride and the like. In the ethylenically unsaturated monomer,
The ethylenically unsaturated carboxylic acid and / or ethylenically unsaturated carboxylic acid anhydride is used in an amount of from 1 to 5 based on the total amount of the monomers.
The content is preferably 0% by weight, more preferably 5 to 30% by weight. If the content is less than 1% by weight, it is difficult to impart sufficient water solubility, and if the content exceeds 50% by weight, the resulting resin composition or aqueous resin composition may be undesirably thickened.

The ethylenically unsaturated monomer contains an ethylenically unsaturated monomer having a hydroxyl group or an alkoxymethyl group in order to improve the separation stability of the resulting resin composition and aqueous resin composition. Preferably.
Since the ethylenically unsaturated monomer having these functional groups reacts with the amino resin and the epoxy resin, the polymer of the ethylenically unsaturated monomer contained in the resin composition, the amino resin and the epoxy resin Is further increased, and the separation stability of the resin composition is improved. The ethylenically unsaturated monomer having a hydroxyl group or an alkoxymethyl group is contained in the ethylenically unsaturated monomer in an amount of 1 to 70 with respect to the total amount of the monomer.
It is preferably contained in the range of weight%. Content is 1
If the amount is less than 10% by weight, the effect of improving the compatibility is not sufficient.
If the amount exceeds 0% by weight, three-dimensionalization tends to occur during the reaction, which is not preferable.

The ethylenically unsaturated monomer having a hydroxyl group is not particularly limited. For example, 2-hydroxyethyl (meth) acrylate, 3-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) ) Acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, ethylene glycol mono (meth) acrylate, diethylene glycol mono (meth) acrylate,
N-methylolmethyl (meth) acrylamide and the like.

The ethylenically unsaturated monomer having an alkoxymethyl group is not particularly restricted but includes, for example, N-methoxymethyl (meth) acrylamide, Nn-butoxymethyl (meth) acrylamide,
N-isobutoxymethyl (meth) acrylamide and the like. It is preferable to use an ethylenically unsaturated monomer having an alkoxymethyl group, since the curability of the obtained resin composition and aqueous resin composition is also improved.

The ethylenically unsaturated monomers other than those described above are not particularly restricted but include, for example, alkyl (meth) acrylate, styrene, vinyltoluene,
(Meth) acrylonitrile, vinyl acetate and the like can be used. The polymer of the ethylenically unsaturated monomer is
The content is preferably in the range of 10 to 89% by weight, more preferably 20 to 80% by weight, based on the total solid content of the resin composition. When the content of the polymer is less than 10% by weight, it is difficult to make the obtained resin composition aqueous, and when it exceeds 89% by weight, it is difficult to sufficiently obtain the coating film performance expected from an amino resin or an epoxy resin. Become.

The radical polymerization of an ethylenically unsaturated monomer in a solution containing an amino resin and an epoxy resin is carried out at 50 to 150 ° C. under an inert gas stream in the presence of an initiator.
This takes place over 10 hours. Initiators include benzoyl peroxide, cumene hydroperoxide, t-
Organic peroxides such as butyl hydroperoxide, diisopropyl peroxycarbonate, di-t-butyl peroxide, t-butyl peroxybenzoate, 2,
An azo compound such as 2'-azobisisobutyronitrile and the like can be mentioned. The initiator was 100 ethylenically unsaturated monomers.
It is preferable to use 1 to 20 parts by weight with respect to parts by weight.

The solvent for dissolving the amino resin and the epoxy resin is not particularly limited.
Hydrocarbon solvents such as toluene, xylene, hexane, and cyclohexane; ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone; (n-, iso-) propanol; (n-, iso-, sec-, tert-) butanol , Ethylene glycol (mono-, di-) methyl ether, ethylene glycol (mono-, di-) ethyl ether, ethylene glycol monoisopropyl ether, ethylene glycol (mono-, di-) butyl ether, ethylene glycol monohexyl ether, ethylene glycol Monomethyl acetate, ethylene glycol monoethyl acetate, diethylene glycol (mono-, di-) methyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol Alcohol solvents such as mono isopropyl ether, ester solvents such as butyl ethyl acetate acetate.

The resin composition of the present invention can be easily dissolved or dispersed in an aqueous medium by adding a basic substance such as ammonia, amines or hydroxide of an alkali metal and an aqueous medium. An aqueous resin composition is obtained. When making the resin composition of the present invention aqueous, in a state containing the solvent used in preparing the resin composition, or after removing the solvent, a basic substance and an aqueous medium are added. . The aqueous medium is composed of water and, if necessary, a water-soluble organic solvent. As the water-soluble organic solvent, the alcohol-based solvents exemplified above can be used.

Representative examples of amines include monoethanolamine, ethylamine, dimethylamine, diethylamine, triethylamine, propylamine, dipropylamine, isopropylamine, diisopropylamine,
Examples thereof include triethanolamine, butylamine, dibutylamine, ethylhexylamine, ethylenediamine, propylenediamine, methylethanolamine, dimethylethanolamine, diethylethanolamine, and morpholine, with dimethylethanolamine being particularly preferred.

The aqueous resin composition of the present invention can be used alone or as a binder for an aqueous paint, but if necessary, another aqueous resin can be used in combination. For example, examples of the other aqueous resin include an aqueous acrylic resin, an aqueous epoxy resin, an aqueous polyester resin, an aqueous urethane resin, and the like. The other aqueous resin is preferably contained in the range of 5 to 95% by weight based on the total solid content of the coating. The aqueous coating composition containing the aqueous resin composition of the present invention as a binder includes, if necessary, a dye for coloring and the like, various additives for improving the properties of the cured product, such as fillers, a leveling agent, and a curing agent. , A flame retardant, a thickener, a water-soluble organic solvent, a lubricity-imparting agent, and the like.

[0020]

The present invention will be specifically described below with reference to examples. Hereinafter, “parts” and “%” are “parts by weight”.
And "% by weight" respectively. [Example 1] A regulator for temperature control, a cooling tube, and a stirrer were attached to a separable four-necked flask, and a partially butyl etherified benzoguanamine resin solution (“Cymel 1128” manufactured by Mitsui Cytec, 70% solid content) 225
Part, bisphenol A type epoxy resin (“Epicoat 1002” manufactured by Yuka Shell Co., epoxy equivalent 650) 15
Charge 7.5 parts and 82.5 parts of butyl cellosolve,
After the temperature was raised to 0 ° C. and the inside of the reaction vessel was replaced with nitrogen, 15.8 parts of acrylic acid, 7 parts of ethyl acrylate, 12.3 parts of styrene, and an organic peroxide (“Perbutyl O” manufactured by NOF Corporation) were added through a dropping tube. 1.1 parts were added dropwise over 2 hours. After completion of the dropwise addition, the reaction was continued for another 3 hours to obtain a resin composition solution having a solid content of 70%.

Example 2 To 100 parts of the resin composition solution obtained in Example 1, 3.9 parts of dimethylaminoethanol and 71.1 parts of water were added with sufficient stirring to obtain a solid content of 4 parts.
A 0% aqueous resin composition was obtained.

Example 3 A separable four-necked flask was equipped with a regulator for temperature control, a condenser, and a stirrer, and a partially butyl etherified benzoguanamine resin solution (“Cymel 1128” manufactured by Mitsui Cytec, solid content of 7%) was prepared.
0%) 75 parts, bisphenol A type epoxy resin (“Epicoat 828” manufactured by Yuka Shell Co., Ltd., epoxy equivalent: 18)
9) 7 parts and 127.5 parts of butyl cellosolve were charged, the temperature was raised to about 80 ° C., and the inside of the reaction vessel was replaced with nitrogen.
-29.1 parts of hydroxyethyl methacrylate, 7.3 parts of acrylic acid, 50.8 parts of ethyl acrylate, 58.1 parts of styrene, and 5.8 parts of organic peroxide ("Perbutyl O" manufactured by NOF Corporation) for 2 hours It dripped over. After completion of the dropwise addition, the reaction was continued for another 3 hours to obtain a resin composition solution having a solid content of 70%.

Example 4 1.8 parts of dimethylaminoethanol and 73.2 parts of water were added to 100 parts of the resin composition solution obtained in Example 3 with sufficient stirring to obtain a solid content of 4 parts.
A 0% aqueous resin composition was obtained.

Example 5 A separable four-necked flask was equipped with a regulator for temperature control, a condenser, and a stirrer, and a methyl etherified benzoguanamine resin ("Melan 553" manufactured by Hitachi Chemical Co., Ltd., solid content: 85%) was 267.6. Department,
35 parts of bisphenol A type epoxy resin (“Epicoat 1001”, manufactured by Yuka Shell Co., epoxy equivalent: 475) and 109.9 parts of butyl cellosolve were charged, the temperature was raised to about 80 ° C., and the inside of the reaction vessel was replaced with nitrogen. 2.2 parts of N-methoxymethylacrylamide, 8.8 acrylic acid
Parts, 32.8 parts of ethyl acrylate, 43.8 parts of styrene
Part, organic peroxide ("Perbutyl O" manufactured by NOF Corporation)
2.6 parts were added dropwise over 2 hours. After dropping, 3 more
The reaction was continued for an hour to obtain a resin composition solution having a solid content of 70%. To 100 parts of the obtained resin composition solution, 2.2 parts of dimethylaminoethanol and 72.8 parts of water were added with sufficient stirring to obtain an aqueous resin composition having a solid content of 40%.

Example 6 A separable four-necked flask was equipped with a regulator for temperature control, a condenser, and a stirrer, and 350 parts of methyl etherified benzoguanamine resin (“Melan 553” manufactured by Hitachi Chemical Co., Ltd., solid content: 85%) was prepared. 17.5 parts of a bisphenol A type epoxy resin (“Epicoat 1001” manufactured by Yuka Shell Co., epoxy equivalent: 475) and 97.5 parts of butyl cellosolve were charged, the temperature was raised to about 80 ° C., and the inside of the reaction vessel was purged with nitrogen, and then added dropwise. From a tube, 2-hydroxyethyl methacrylate 7, 10.5 parts of acrylic acid, 17.5 parts of styrene, and 0.7 part of an organic peroxide ("Perbutyl O" manufactured by NOF CORPORATION) were dropped over 2 hours. After completion of the dropwise addition, the reaction was continued for another 3 hours to obtain a resin composition solution having a solid content of 70%. In 100 parts of the obtained resin composition solution,
2.6 parts of dimethylaminoethanol and 72.4 parts of water were added with sufficient stirring to obtain an aqueous resin composition having a solid content of 40%.

Comparative Example 1 A separable four-necked flask was equipped with a temperature control regulator, a condenser, and a stirrer, and a methyl etherified benzoguanamine resin ("Melan 553" manufactured by Hitachi Chemical Co., Ltd., solid content: 85%) was 267.6. Department,
94.9 parts of butyl cellosolve was charged, the temperature was raised to about 80 ° C., and the inside of the reaction vessel was replaced with nitrogen.
Parts, 32.8 parts of ethyl acrylate, 43.8 parts of styrene
Part, organic peroxide ("Perbutyl O" manufactured by NOF Corporation)
2.6 parts were added dropwise over 2 hours. After dropping, 3 more
The reaction was continued for an hour to obtain a resin composition solution having a solid content of 70%. To 100 parts of the obtained resin composition solution, 2.4 parts of dimethylaminoethanol and 72.6 parts of water were added with sufficient stirring to obtain an aqueous resin composition having a solid content of 40%.

[Comparative Example 2] To 100 parts of the resin composition solution obtained in Comparative Example 1, 7.8 parts of a bisphenol A type epoxy resin (“Epicoat 828” manufactured by Yuka Shell Co., epoxy equivalent 189), dimethylamino 2.4 parts of ethanol and 84.3 parts of water were added with sufficient stirring to obtain an aqueous resin composition having a solid content of 40%.

Comparative Example 3 Partially butyl etherified benzoguanamine resin (Cymel 1 manufactured by Mitsui Cyanamid Co., Ltd.)
128 ", solid content 70%) 45 parts, epoxy resin (" Epicoat 1002 "manufactured by Yuka Shell Co., Ltd., epoxy equivalent 65)
0) To 31.5 parts, 81.7 parts of a water-soluble acrylic resin (triethylamine neutralized product of “Johncryl 587” manufactured by Johnson Polymer Co., solid content 30%) and 16.8 parts of water were added with sufficient stirring. Thus, an aqueous resin composition having a solid content of 40% was obtained.

[Comparative Example 4] A bisphenol A-type epoxy resin ("Epicoat 1002" manufactured by Yuka Shell Co., epoxy equivalent 650) was attached to a separable four-necked flask equipped with a regulator for controlling temperature, a cooling tube, and a stirring device.
6.3 parts, 150 parts of butyl cellosolve are charged, and
After the temperature was raised to 0 ° C. and the inside of the reaction vessel was replaced with nitrogen, 28.7 parts of acrylic acid, 12.7 parts of ethyl acrylate,
22.3 parts of styrene and 1.9 parts of an organic peroxide (“Perbutyl O” manufactured by NOF Corporation) were added dropwise over 2 hours. After completion of the dropwise addition, the reaction was continued for another 3 hours to obtain a resin composition solution having a solid content of 70%. In 55 parts of the obtained resin composition solution,
Partially butyl etherified benzoguanamine resin solution (“Cymel 1128”, manufactured by Mitsui Cytec, solid content 70%)
After adding and dissolving 45 parts, 3.9 parts of dimethylaminoethanol and 71.1 parts of water were added with sufficient stirring to obtain an aqueous resin composition having a solid content of 40%.

The resin composition solutions obtained in Examples 1 and 3 were adjusted to a solid content of 40% with butyl cellosolve, and the aqueous resins obtained in Examples 2, 4, 5, 6 and Comparative Examples 1 to 4. After storage at 50 ° C. for 3 weeks, the composition was evaluated for stability. Also, 0.4 part of p-toluenesulfonic acid was added to 100 parts of the resin composition solution or the aqueous resin composition adjusted to a solid content of 40%, and tinned with a wire bar coater so that the dry coating thickness became about 15 μm. The coating was applied to a free steel plate and dried at 200 ° C. for 2 minutes to evaluate the adhesion of the film obtained. In addition, the adhesiveness is represented by the ratio of the number of squares remaining without being peeled off in a crosscut cellophane tape peeling test. Further, 0.4 part of p-toluenesulfonic acid was added to 100 parts of the resin composition solution or the aqueous resin composition adjusted to a solid content of 40%, and 5 g was spread on five metal dishes having a diameter of 20 cm. 5 ℃ in a vacuum oven
The fume component after baking for minutes was collected by a liquid nitrogen trap, and the amount of the sample was measured. Table 1 shows the results.

[0031]

[Table 1]

[0032]

The aqueous resin composition of the present invention is excellent in separation stability, has good substrate adhesion, durability and the like in its cured film, and has a small amount of fume generated during the coating baking process. It can be used for a wide range of applications as a binder for paints, aqueous inks, adhesives, sealing agents, and the like, and is extremely useful industrially.

Claims (8)

[Claims] An ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic acid anhydride is polymerized in the presence of an amino resin and an epoxy resin. A resin characterized in that a part of the polymer of the ethylenically unsaturated monomer is chemically bonded and a part of the epoxy resin and the polymer of the ethylenically unsaturated monomer are chemically bonded. Composition. 2. The resin composition contains 10 to 89% by weight of an amino resin, 1 to 50% by weight of an epoxy resin and 10 to 89% by weight of a polymer of an ethylenically unsaturated monomer, based on the total solid content of the resin composition. The resin composition according to claim 1, wherein: 3. An ethylenically unsaturated monomer containing 1 to 70% by weight of an ethylenically unsaturated monomer having a hydroxyl group or an alkoxymethyl group, based on the total amount of the monomer. The resin composition according to claim 1, wherein 4. An ethylenically unsaturated monomer containing 1 to 50% by weight of an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic acid anhydride based on the total amount of the monomer. The resin composition according to any one of claims 1 to 3, characterized in that: 5. An aqueous resin composition obtained by dissolving or dispersing the resin composition according to any one of claims 1 to 4 in an aqueous medium in the presence of a basic substance. 6. An aqueous paint comprising the aqueous resin composition according to claim 5 as a binder. 7. A radical polymerization of an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic anhydride in a solution containing an amino resin and an epoxy resin. A method for producing a resin composition. 8. A resin composition obtained by radical polymerizing an ethylenically unsaturated monomer containing an ethylenically unsaturated carboxylic acid and / or an ethylenically unsaturated carboxylic anhydride in a solution containing an amino resin and an epoxy resin. , A basic substance and an aqueous medium are added, and the resin composition is dissolved or dispersed in the aqueous medium.