JP6725868B2 - Modified epoxy resin for paint and one-component/lacquer type paint - Google Patents

Description

The present invention relates to a modified epoxy resin for paint and a one-pack/lacquer type paint.

The bisphenol type epoxy resin obtained from bisphenol and epichlorohydrin, etc. is a coating material having excellent corrosion resistance, adhesion, chemical resistance, etc. due to the reactivity of the epoxy groups and hydroxyl groups that it has Widely used as a resin for automobiles.

However, since the bisphenol type epoxy resin generally has no self-curing property, it is used as a two-component reaction type coating material containing a polyfunctional amine, a polyamide polyamine or the like as a curing agent.

However, the two-component reactive coating is inconvenient to handle because it requires that the curing agent be added to the main component immediately before it is applied to the base material, and there are various practical limitations in terms of pot life (pot life). is there. Therefore, there has been a long-felt need for a one-component/lacquer type coating resin that maintains the properties such as adhesion and corrosion resistance as a bisphenol type epoxy resin, can be dried at room temperature, and does not require the addition of a curing agent.

Examples of such a one-component/lacquer-type coating resin include urethane-modified epoxy resins obtained by ring-opening an epoxy resin with amines or the like and further reacting with a polyisocyanate compound (see Patent Documents 1 and 2). reference). These urethane-modified epoxy resins have properties such as corrosion resistance, adhesion, and chemical resistance, which are the characteristics of epoxy resins, and can be cured at room temperature.

However, in recent years, in a one-component lacquer type paint, while maintaining various properties such as corrosion resistance of the coating film, while forming a coating film with improved flexibility, a coating material with a low content of organic solvent, that is, It has been desired to develop a modified epoxy resin for paints that can realize high solidification (high solidification) of paints.

JP, 2010-235919, A JP-A-11-17199

The present invention is to solve the above problems, while maintaining the coating performance such as the anticorrosion properties of the modified epoxy resin, it is possible to further improve the flexibility of the coating and high solidification of the coating, An object is to provide a modified epoxy resin for paints.

As a result of extensive studies conducted by the present inventor to solve the above problems, an amine-modified epoxy resin containing a specific amount of a diamine as an essential component, and a modified epoxy resin for a coating obtained by reacting a polyisocyanate are used. The inventors have found that the problems can be solved and completed the present invention.

That is, the present invention is described in the following items 1 to 7.

Item 1. A reaction product of an amine-modified epoxy resin (A) and a polyisocyanate (B),
The amine-modified epoxy resin (A) comprises bisphenol type epoxy resin (a1), diamine (a2) 0.1 to 50% by weight, and other amine (a3) 50 to 99.9% by weight (provided that (a2) and The total of (a3) is 100% by weight),
All SANYO to / {(a2) and the total number active hydrogen of the amino group of (a3)} is reacted at a ratio of 100 / 90-100 / 110 {the number of epoxy groups (a1)},
The diamine (a2) is at least one selected from the group consisting of propyldiamine, isophoronediamine and dimerdiamine,
The group in which the other amine (a3) is composed of alkanolamines, ethylamine, propylamine, butylamine, hexylamine, laurylamine, stearylamine, palmitylamine, oleylamine, 2-ethylhexylamine, diethylamine, dipropylamine and dibutylamine. One or more selected from
The modified epoxy resin for coatings , wherein the polyisocyanate (B) is an alicyclic polyisocyanate .

Item 2. The dimer diamine is a compound represented by the following general formula (1) and / or (2) represented Ru item 1 wherein the coating-modified epoxy resin.
(In Formula (1), m+n=5 to 16 and p+q=8 to 19, and the wavy line represents a carbon-carbon single bond or a double bond.)
(In the formula (2), m+n=5 to 16 and p+q=8 to 19, and the wavy line portion represents a carbon-carbon single bond or a double bond.)

Item 3. The modified epoxy resin for coating according to the above 1 or 2, wherein the other amine (a3) contains 1 to 50% by weight of an alkanolamine.

Item 4. The use ratio of the amine-modified epoxy resin (A) and the polyisocyanate (B) is such that {number of isocyanate groups in (B)}/{number of hydroxyl groups in (A)} is 0.1×10 ^{−2 to} 0.30. The modified epoxy resin for coating according to any one of items 1 to 3 above.

Item 5. A one-pack lacquer type paint using the modified epoxy resin for paint according to any one of items 1 to 4 above.

Item 6. The one-component/lacquer type coating composition according to claim 5, wherein the nonvolatile content is 50% by weight or more.

Item 7. A method for producing a reaction product of an amine-modified epoxy resin (A) and a polyisocyanate (B), comprising:
The amine-modified epoxy resin (A) comprises bisphenol type epoxy resin (a1), diamine (a2) 0.1 to 50% by weight, and other amine (a3) 50 to 99.9% by weight (provided that (a2) and The total of (a3) is 100% by weight),
/ {(A2) and the total number active hydrogen of the amino group of (a3)} is have a step of reacting at a rate of 100 / 90~100 / 110 {(a1 ) the number of epoxy groups},
The diamine (a2) is at least one selected from the group consisting of propyldiamine, isophoronediamine and dimerdiamine,
The group in which the other amine (a3) is composed of alkanolamines, ethylamine, propylamine, butylamine, hexylamine, laurylamine, stearylamine, palmitylamine, oleylamine, 2-ethylhexylamine, diethylamine, dipropylamine and dibutylamine. One or more selected from
The method for producing a modified epoxy resin for coating material , wherein the polyisocyanate (B) is an alicyclic polyisocyanate .

According to the present invention, by using a diamine, it is possible to further improve the flexibility of the coating film and realize high solidification of the coating material while maintaining the coating performance such as anticorrosion property and water-resistant adhesiveness. A modified epoxy resin can be provided. Further, the one-pack/lacquer type coating composition of the present invention obtained by using the modified epoxy resin is suitable from the viewpoint of environmental suitability since it can reduce the solvent content.

The modified epoxy resin for paints of the present invention is a reaction between an amine-modified epoxy resin (A) (hereinafter, also referred to as “(A) component”) and a polyisocyanate (B) (hereinafter, also referred to as “(B) component”). In the product, the component (A) is a bisphenol type epoxy resin (a1) (hereinafter, also referred to as “(a1) component”) and a diamine (a2) (hereinafter, also referred to as “(a2) component”) 0.1. ˜50 wt% and other amine (a3) (hereinafter, also referred to as “(a3) component”) 50 to 99.9 wt% (however, the total of (a2) and (a3) is 100 wt %). Is obtained by reacting an amine compound consisting of {(a1) component epoxy group}/{(a2) component and (a3) component amino group active hydrogen number} at a ratio of 100/90 to 100/110. ..

Examples of the component (a1) include those obtained by reacting bisphenols with a haloepoxide such as epichlorohydrin or β-methylepichlorohydrin. As bisphenols, phenol or 2,6-dihalophenol is reacted with aldehydes or ketones such as formaldehyde, acetaldehyde, acetone, acetophenone, cyclohexanone, benzophenone, etc., oxidation of dihydroxyphenyl sulfide with peracid, hydroquinone Those obtained by the etherification reaction of Specific examples of bisphenols include 2,2-bis(4-hydroxyphenyl)propane (bisphenol A) and bis(4-hydroxyphenyl)methane (bisphenol F). The component (a1) is used alone or in an appropriate combination of two or more kinds.

The epoxy equivalent of the component (a1) is not necessarily limited, but from the viewpoint of lowering the viscosity, it is preferably about 5,000 or less, more preferably about 100 to 2,000. When the epoxy equivalent is within the above range, the molecular weight of the resulting modified epoxy resin for coating does not increase excessively and the resin has a relatively low viscosity, so that the coating obtained using the resin can be easily made into a high solid. Has the advantage that

Further, the raw material of the component (A) may be used in combination with another epoxy resin other than the component (a1) within a range in which the corrosion resistance of the resulting modified epoxy resin can be maintained. Specific examples include aromatic epoxy resins such as aliphatic epoxy resins and novolac type epoxy resins.

Examples of the aliphatic epoxy resin include resins containing glycidyl ester of long-chain aliphatic dibasic acid, glycidyl ether of long-chain aliphatic polyol, glycidyl ether of polyether polyol, and the like. Examples of the long-chain aliphatic dibasic acid include sebacic acid, azelaic acid, dodecanoic acid, malonic acid, succinic acid, glutaric acid, adipic acid, 8,11-dimethyl-7,11-octadecadiene-1,18. -Dicarboxylic acid, 7-ethyloctadecanedicarboxylic acid, 1,4-cyclohexenecarboxylic acid and the like. Examples of the long-chain aliphatic polyol include 1,4-butanediol, 1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,9-nonanediol and 1,10-decane. Examples include diol and the like. Further, as the polyether polyol, for example, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, pentaethylene glycol, hexaethylene glycol, heptaethylene glycol, octaethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, Examples include tetrapropylene glycol, pentapropylene glycol, hexapropylene glycol, polyethylene glycol, polypropylene glycol, polyoxyethylene polyoxypropylene glycol, polybutylene glycol and the like. These may be used alone or in appropriate combination of two or more. Further, the ratio of the other epoxy resin used is preferably 50% by weight or less, with the total amount of the component (a1) and the epoxy resin being 100% by weight.

The component (a2) is not particularly limited as long as it is a diamine, and examples thereof include ethylenediamine, propylenediamine, hexamethylenediamine, 2.2.4 trimethylhexanediamine, 2.4.4 trimethylhexanediamine, isophoronediamine, A dimer diamine is mentioned. Among these, dimer diamine is preferable in terms of appropriate flexibility of the coating film and improvement of rust prevention.

The dimer diamine is a compound derived from dimer acid which is a dimer of unsaturated fatty acid such as oleic acid, as described in JP-A-9-12712. In the present invention, known dimer diamines can be used without particular limitation, but in order to achieve a high concentration and low viscosity of the resulting modified epoxy resin, the dimer diamine used is represented by the following general formula (1) and/or general formula The dimer diamine represented by (2) is preferable, and the dimer diamine represented by the general formula (1)′ is more preferable.

(In the formula (1), m+n=5 to 16 and p+q=8 to 19 and represents a carbon-carbon single bond or a double bond.)

(In the formula (2), m+n=5 to 16 and p+q=8 to 19 and represents a carbon-carbon single bond or a double bond.)

Examples of commercially available products of the above dimer diamine include Versamine 551 (manufactured by BASF Japan Ltd.), Versamine 552 (manufactured by Henkel Japan Ltd.; hydrogenated product of Versamine 551), PRIAMINE1071, PRIAMINE1074, PRIAMINE1075 (all are Croda Japan ( Co., Ltd.) and the like.

The ratio of the component (a2) used is about 0.1 to 50% by weight, preferably 1 to 50% by weight, more preferably 100% by weight based on the total 100% by weight of the components (a2) and (a3). It is 5 to 50% by weight. If the usage ratio is less than 0.1% by weight, the viscosity tends to increase, and if it exceeds 50% by weight, gelation tends to occur, and the hardness and water resistance of the coating film tend to decrease.

Examples of the component (a3) include alkanolamines, aliphatic amines, aromatic amines, alicyclic amines, and aromatic nucleus-substituted aliphatic amines having a carbon number of about 2 to 20. These may be used alone or in appropriate combination of two or more kinds. Among these, alkanolamines are preferable from the viewpoint of improving the adhesion to the material.

Examples of the alkanolamines include monoethanolamine, diethanolamine, monoisopropanolamine, diisopropanolamine, di-2-hydroxybutylamine, N-methylethanolamine, N-ethylethanolamine, N-benzylethanolamine and the like. These may be used alone or in appropriate combination of two or more. In the production of the modified epoxy resin for paints of the present invention, in consideration of the reactivity between the components (A) and (B) and the adjustment of the molecular weight of the resulting modified epoxy resin, among the components (a3), alkanolamine The use amount of the class is about 1 to 50% by weight, preferably 1 to 40% by weight.

Examples of the aliphatic amines include primary amines such as ethylamine, propylamine, butylamine, hexylamine, laurylamine, stearylamine, palmitylamine, oleylamine and erucylamine, and secondary amines such as diethylamine, dipropylamine and dibutylamine. Examples include amines. Examples of the aromatic amines include toluidines, xylidines, cumidine (isopropylaniline)s, hexylanilines, nonylanilines, dodecylanilines and the like. Examples of the alicyclic amines include cyclopentylamines, cyclohexylamines, norbornylamines. Examples of aromatic nucleus-substituted aliphatic amines include benzylamine and phenethylamine. These amines may be used alone or in appropriate combination of two or more.

The proportion of the component (a3) used is about 50 to 99.9% by weight per 100% by weight of the total of the components (a2) and (a3), preferably from the viewpoint of high solidification and rust prevention. It is 50 to 99% by weight, more preferably 50 to 95% by weight.

The component (A) can be produced by reacting the components (a1), (a2) and (a3) under the following conditions. That is, the number of epoxy groups in the component (a1)}/{the number of active hydrogens in the total amino groups in the components (a2) and (a3)} is 100/90 or more in that unreacted substances of each component can be reduced. The amount of each component used is determined so as to be about 100/110.

The reaction temperature in the production of the component (A) is usually about 50 to 250°C, preferably about 80 to 150°C. If the reaction temperature is lower than 50° C., the reaction rate becomes too small, and if it exceeds 250° C., the reaction between the epoxy group and the hydroxyl group of the component (a1) or the reaction between the epoxy groups occurs, and the reaction product becomes a gel. It may be easy to change. The reaction time is not particularly limited because it depends on the reaction temperature, but it is usually about 3 to 10 hours, preferably 3 to 6 hours from the viewpoint of production efficiency. It is presumed that the modified epoxy resin finally obtained can be made highly solid by incorporating the diamine as a branched chain and appropriately incorporating the diamine into the epoxy compound.

Examples of the component (B) include various known aromatic, aliphatic or alicyclic polyisocyanates, which may be used alone or in appropriate combination of two or more kinds. Specific examples of the component (B) include 1,5-naphthylene diisocyanate, 4,4′-diphenylmethane diisocyanate, 4,4′-diphenyldimethylmethane diisocyanate, 4,4′-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate and tetra. Alkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4 -Trimethylhexamethylene diisocyanate, lysine diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, methylcyclohexane diisocyanate, orthotoluidine diisocyanate, Examples thereof include polyphenyl polyisocyanate and isophorone diisocyanate. Of these polyisocyanates, tolylene diisocyanate, hexamethylene diisocyanate, isophorone diisocyanate and the like are preferable.

In the production of the modified epoxy resin for paints of the present invention, {number of isocyanate groups in component (B)}/{number of hydroxyl groups in component (A)} is about 0.1×10 ^{−2 to} 0.3, preferably 0. Both components may be reacted so as to be 5×10 ^{−2 to} 0.25. When it is 0.1×10 ⁻² or more, the resulting modified epoxy resin for coating has a moderately high molecular weight and is suitable as a one-pack type lacquer coating resin which can be dried at room temperature. On the other hand, when it is 0.3 or less, excessive high molecular weight can be suppressed, which is suitable for preparation of high solid type paint. More preferably, it is 0.015 to 0.15.

The reaction conditions of the above-mentioned component (B) and component (A) are not particularly limited, but the reaction temperature is usually about 20 to 200°C, preferably 50 to 150°C. The reaction time is usually about 3 to 10 hours, preferably 3 to 6 hours from the viewpoint of production efficiency.

A solvent can be used in the above reaction, but it must be inert to each component. Examples of the inert solvent include hydrocarbons such as toluene and xylene, ketones such as methyl ethyl ketone, methyl isobutyl ketone and cyclohexanone, esters such as ethyl acetate and butyl acetate, methyl cellosolve acetate, cellosolve acetate such as cellosolve acetate. And the like, which do not have active hydrogen, may be used alone or in combination of two or more kinds as appropriate. After the production of the modified epoxy resin for paint of the present invention, a solvent having active hydrogen such as cellosolves such as methyl cellosolve and ethyl cellosolve; alcohols such as isopropyl alcohol and n-butyl alcohol; as a diluting solvent. It can be used without any problem.

The weight average molecular weight (polystyrene conversion value by gel permeation chromatography) of the modified epoxy resin for coating material of the present invention is not particularly limited, but is preferably in the range of about 5,000 to 100,000. By adjusting the weight average molecular weight to 5,000 or more, a one-component lacquer type coating resin having long-term high corrosion resistance, water resistance, etc. can be obtained. A resin suitable for the above high solid type paint can be obtained.

The solid content concentration of the modified epoxy resin for coating material of the present invention is not particularly limited and may be appropriately determined in consideration of the viscosity when formed into a coating material, but is usually about 30 to 80% by weight. It Further, from the viewpoint of handleability of the obtained coating material, the viscosity of the resin solution is adjusted to about R to Z ₇ (Gardner method, 25° C.) before use.

The one-pack/lacquer type coating material of the present invention (hereinafter referred to as the present coating material) using the modified epoxy resin for coating material of the present invention is described below. The paint can be used as a paint for drying at room temperature, and is also suitable as a forced-dry paint, a baking paint, and the like. Further, the present coating material can be widely applied without particular limitation such as the object to be coated and the application, but it is suitable for undercoating in consideration of performances such as anticorrosion and adhesion.

In the preparation of the present coating composition, color pigments such as carbon black and titanium oxide, extender pigments such as talc, calcium carbonate and barium sulfate, and rust preventive pigments such as aluminum phosphomolybdate and zinc phosphate can be appropriately mixed. In addition, a curing agent such as a melamine resin, a urea resin, an isocyanate and a blocked isocyanate, various known solvents, and other additives may be appropriately added to the present coating material, if necessary. When the coating composition is prepared as a high solid type, the nonvolatile content is usually about 50 to 80% by weight, preferably 70 to 80% by weight, and the solvent content is usually about 20 to 50% by weight, preferably 20 to 50% by weight. It is set to 30% by weight.

Hereinafter, the present invention will be described more specifically by way of examples. However, the present invention is not limited to these examples. In the examples, "parts" means "parts by weight" unless otherwise specified.

Example 1
In a reaction vessel equipped with a stirrer, a cooler, a thermometer and a nitrogen gas introduction tube, 900 parts of bisphenol type epoxy resin (1) (Mitsubishi Chemical Co., Ltd., trade name "JER1001", epoxy equivalent 475 g/eq), Bisphenol type epoxy resin (2) (manufactured by Nippon Steel & Sumitomo Metal Corporation, trade name "YD-128", epoxy equivalent 189 g/eq) 300 parts, dimer diamine (manufactured by Croda, trade name "PRIAMINE1071") 123 parts, stearylamine 46 Parts, diethanolamine 60 parts, monoethanolamine 11 parts, 2-ethylhexylamine 30 parts and xylene 724 parts were charged, and these were reacted under a nitrogen stream at 100° C. for 5 hours to obtain an amine-modified epoxy resin (A1). .. Next, 24 parts of isophorone diisocyanate (B) and 270 parts of cyclohexanone were charged in the same reaction vessel, and these were reacted under a nitrogen stream at 100° C. for 4 hours to obtain a modified epoxy resin for coating. The physical properties of this resin are shown in Table 1. The weight average molecular weight was measured by the following method.

(Measurement of weight average molecular weight)
Device: HLC-8220 (manufactured by Tosoh Corporation)
Column: TSKgel α-2500×1, α-3000×1
Separation solvent: DMF (containing LiBr 5 mmol/kg),
Flow rate: 1 ml/min
Temperature: 40°C
Standard: polystyrene

Examples 2-10 and Comparative Examples 1-4
(A1) component type, (a2) component type and (a3) component type, (a2) component and (a3) component usage rate, {(a1) component epoxy group number} and {(a2) component and Other than changing at least one of the use ratio of (a3) component with the number of active hydrogen of amino group} and the use ratio of (A) component and (B) component as shown in Table 1. The reaction was carried out in the same manner as in Example 1 to obtain various modified epoxy resins for paints. Table 1 shows these physical property values. In Comparative Example 1, the molecular weight and viscosity of the modified epoxy resin became high and gelled.

In Table 1, the numerical values relating to the component (a1), the component (a2), the component (a3), and the component (B) all indicate parts by weight charged. Each symbol means the following.
JER1001: Bisphenol type epoxy resin (1) (Mitsubishi Chemical Corporation, trade name "JER1001", epoxy equivalent 475 g/eq)
YD-128: Bisphenol type epoxy resin (2) (manufactured by Nippon Steel & Sumitomo Metal Corporation, trade name "Epototo YD-128", epoxy equivalent 189 g/eq)
Priamine 1071: dimer diamine (made by Croda Japan Co., Ltd.)
Versamine 551: dimer diamine (manufactured by BASF Japan Ltd.)
IPD: Isophoronediamine SA: Stearylamine DEA: Diethanolamine MEA: Monoethanolamine 2EHA: 2-Ethylhexylamine DBA: Dibutylamine Functional group ratio: {Number of epoxy groups in component (a1)}/{(a2) component and component (a3) Number of active hydrogens in the amino group of
IPDI: Isophorone diisocyanate NV (%): Solid content concentration Mw: Weight average molecular weight Vis: Gardner viscosity (25°C)

(Preparation of various paints and test coatings)
A mixture of the following compositions was kneaded with a paint shaker to prepare a lacquer type paint. The obtained coating material was applied on a degreased dull steel plate (SPCC-SD, 0.8×70×150 mm) by a bar coater so that the film thickness after drying was 30 μm, and forced drying (80° C.×20 mm). After that, the sample was left to stand at room temperature (20° C., 60% RH) for 6 days to prepare a test coating film, and the test film was subjected to the following tests.

(composition)
200 parts of each lacquer type coating resin obtained in Examples 1 to 10 and Comparative Examples 2 to 4 (solid content: 120 parts)
Titanium oxide 80 parts Carbon black 4 parts Precipitating barium sulphate 80 parts Aluminum phosphate anticorrosion pigment 16 parts Xylene 25 parts Cyclohexanone 25 parts

(Coating film evaluation test)
(1) Pencil hardness Based on JIS K5600-5-4.

(2) Flexibility (bending test)
Each coating was applied on a chin-free steel plate (0.3×120×200 mm) by a bar coater so that the film thickness after drying was 30 μm, and after forced drying (80° C.×20 minutes), room temperature ( The test piece was obtained by allowing to stand at 20° C. and 60% RH for 6 days. Each test piece was bent with a vise, and the presence or absence of cracks in the bent portion was confirmed. The flexibility was evaluated by the number of plates (chin-free steel plates) sandwiched between them (2T means that the sandwiched plates are bent with two plates and there is no crack).

(3) Primary adhesion It was performed according to JIS K5600-5-6, and after coating, 23° C., 50% R.S. H. The cross-cut adhesion when the test coating film aged for 6 days in the above environment was peeled off was evaluated as 100.

(4) Water-resistant adhesiveness It was performed according to JIS K5600-6-2, and the cross-cut adhesiveness when the test coating film immersed in 40°C warm water for 10 days was peeled off was evaluated as 100.

(5) Anticorrosion property It carried out according to JIS K5600-7-9, and it showed with the cellophane tape peeling width (mm) after 10 days and 20 days of a salt spray test.
The results of these evaluations are shown in Table 1.

In Comparative Examples 2 and 3, since the resin had a high viscosity, the pigment was not sufficiently dispersed, and it was impossible to form a paint. From the results in Table 1, the coating films obtained in the present invention (Examples) have an excellent balance of viscosity, pencil hardness, flexibility, primary adhesiveness, water-resistant adhesiveness, and corrosion resistance, as compared with Comparative Example 4. The deviation performance was also good.

Claims (7)

A reaction product of an amine-modified epoxy resin (A) and a polyisocyanate (B),
The amine-modified epoxy resin (A) comprises bisphenol type epoxy resin (a1), diamine (a2) 0.1 to 50% by weight, and other amine (a3) 50 to 99.9% by weight (provided that (a2) and The total of (a3) is 100% by weight),
All SANYO to / {(a2) and the total number active hydrogen of the amino group of (a3)} is reacted at a ratio of 100 / 90-100 / 110 {the number of epoxy groups (a1)},
The diamine (a2) is at least one selected from the group consisting of propyldiamine, isophoronediamine and dimerdiamine,
The group in which the other amine (a3) is composed of alkanolamines, ethylamine, propylamine, butylamine, hexylamine, laurylamine, stearylamine, palmitylamine, oleylamine, 2-ethylhexylamine, diethylamine, dipropylamine and dibutylamine. One or more selected from
The modified epoxy resin for coatings , wherein the polyisocyanate (B) is an alicyclic polyisocyanate . The dimer diamine is a compound represented by the following general formula (1) and / or (2) represented Ru claim 1 for coatings modified epoxy resin according.
(In Formula (1), m+n=5 to 16 and p+q=8 to 19, and the wavy line represents a carbon-carbon single bond or a double bond.)
(In the formula (2), m+n=5 to 16 and p+q=8 to 19, and the wavy line portion represents a carbon-carbon single bond or a double bond.) The other amine (a3) contains 1 to 50% by weight of alkanolamines according to claim 1 or 2 Symbol placement of paint modified epoxy resin. The use ratio of the amine-modified epoxy resin (A) and the polyisocyanate (B) is such that {number of isocyanate groups in (B)}/{number of hydroxyl groups in (A)} is 0.1×10 ^{−2 to} 0.30. The modified epoxy resin for coating according to any one of claims 1 to 3, which is a resin. A one-pack lacquer type paint using the modified epoxy resin for paint according to any one of claims 1 to 4. The one-pack lacquer type coating composition according to claim 5, wherein the nonvolatile content is 50% by weight or more. A method for producing a reaction product of an amine-modified epoxy resin (A) and a polyisocyanate (B), comprising:
The amine-modified epoxy resin (A) comprises bisphenol type epoxy resin (a1), diamine (a2) 0.1 to 50% by weight, and other amine (a3) 50 to 99.9% by weight (provided that (a2) and The total of (a3) is 100% by weight),
/ {(A2) and the total number active hydrogen of the amino group of (a3)} is have a step of reacting at a rate of 100 / 90~100 / 110 {(a1 ) the number of epoxy groups},
The diamine (a2) is at least one selected from the group consisting of propyldiamine, isophoronediamine and dimerdiamine,
The group in which the other amine (a3) is composed of alkanolamines, ethylamine, propylamine, butylamine, hexylamine, laurylamine, stearylamine, palmitylamine, oleylamine, 2-ethylhexylamine, diethylamine, dipropylamine and dibutylamine. One or more selected from
The method for producing a modified epoxy resin for coating material , wherein the polyisocyanate (B) is an alicyclic polyisocyanate .