JPH01167356A - Curable resin composition and method for curing - Google Patents

Abstract

PURPOSE:To obtain the title resin composition, containing a resin having alpha,beta-unsaturated carbonyl groups, resin having hydroxyl groups and specific curing catalyst, crosslinkable and curable at a relatively low temperature without producing by-products or yellowing of films in hot curing. CONSTITUTION:A composition containing(A) a resin having alpha,beta-unsaturated carbonyl groups (e.g., methacryloyl or maleate group) in an amount of 0.01-20mol, preferably 0.1-5mol based on 1kg resin, (B) a resin having primary or secondary OH groups in an amount of 0.01-50mol, preferably 0.1-10mol based on 1kg resin without any alpha,beta-unsaturated carbonyl group and (C) a curing catalyst of one or more of alkaline (earth) metal hydroxides, alkaline (earth) metal salts of organic acids, quaternary ammonium bases (organic acid salts), quaternary phosphonium bases (organic acid salts), quaternary sulfonium bases (organic acid salts) and alkaline metal oxides.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention provides a resin composition excellent as a violet resin composition that can be crosslinked and cured at a relatively low temperature, and a It relates to a curing method in which the reaction with hydroxyl groups is carried out by heating in the presence of a curing catalyst.

[Prior Art] Conventionally, as a method for curing coating resins, hydroxyl groups are often contained as functional groups in the resin, and these hydroxyl groups are heated and reacted with a crosslinking agent such as a melamine resin or a blocked isocyanate. This method has the disadvantage that by-products are generated during curing, which contaminates the inside of the dry blast oven and adversely affects the appearance of the cured film surface.

In addition, individual thermal polymerization of α, β-unsaturated carbonyl groups and α
There is an example of utilizing an addition reaction between a β-unsaturated carbonyl group and an amine. However, when using only heat, a considerably high temperature is required for curing, and the coating surface is inhibited from curing by oxygen.On the other hand, the addition reaction between α, β-unsaturated luponyl and amine is carried out at a low temperature. Although curable, these compositions have the disadvantage that the cured film is susceptible to deterioration and that these compositions have poor storage stability.

[Problems to be Solved by the Invention] The present inventor has devised a method that does not have the above two drawbacks, that is, does not generate by-products or yellow the film during heat curing, crosslinks and cures at a relatively low temperature, and Research has been carried out for many years in order to find a curable resin composition with good storage stability and a curing method.

[Means for solving the problem] As a result, resins having α,β-unsaturated carbonyl groups and resins having primary or secondary hydroxyl groups without α,β-unsaturated carbonyl groups were found. A composition formed by containing a specific curing catalyst in a mixture is crosslinked and cured at a relatively low temperature, has excellent storage stability, and the reaction during heat curing is mainly the addition of hydroxyl groups to unsaturated groups. Therefore, the present invention was achieved by discovering that there are no defects or changes in film value due to the generation of by-products, and the coated surface has excellent smoothness. That is, the present invention provides (1) (a) a tree 1 having an α,β-unsaturated carbonyl group;
(b) A resin having no α,β-unsaturated carbonyl group and having a primary or secondary hydroxyl group, and (C) an alkali metal hydroxide, an alkali metal-containing a M tl! , alkaline earth metal hydroxide, alkaline earth metal organic acid salt, quaternary ammonium base, quaternary ammonium organic acid salt, quaternary phosphonium base, quaternary phosphonium organic acid salt, tertiary sulfonium base , a curable resin composition comprising at least one curing catalyst selected from a tertiary sulfonium organic acid salt and an alkali metal oxide, and (2) (a) α
, a resin having a β-unsaturated carbonyl group, and (b) a resin having no α, β-unsaturated carbonyl group and having a primary or secondary hydroxyl group, (C) an alkali metal hydroxide, an alkali metal organic acid 1f
J, alkaline earth metal hydroxide, alkaline earth metal organic acid salt, quaternary ammonium base, quaternary ammonium organic acid salt, quaternary phosphonium base, quaternary phosphonium organic acid salt, tertiary sulfonium The present invention provides a curing method characterized by curing by heating in the presence of at least one curing catalyst selected from a base, a tertiary sulfonium organic acid salt, and an alkali metal oxide.

(a) In undeveloped IjI, (a) a resin having an α,β-unsaturated group, -, an α,β-unsaturated group, such as acryloyl group, methacryloyl group, (, itaconate group, Malenito 1(, coumarate 1(, crotonate group, cinnamic acid), (, acrylamide group, methacrylamide group), etc.

(b) α, β-unsaturated carponyl in the present invention, (
Among the resins having primary or secondary hydroxyl groups without having hydroxyl groups, primary hydroxyl groups are more preferable in terms of curability.

(a) As the resin, α, β-unsaturated power luponyl, (
There are no particular limitations as long as the resin has There is no particular limitation as long as the resin is
As the resins (a) and (b), acrylic, polyester, urethane, polybutadiene, alkyd, epoxy, polyether, polyamide and phenol resins can be used. The molecular weights of (a) resin and (b) 461 fat are not particularly limited, but each has a peak molecular weight of 250 to 10 by gel permeation chromatography (GPC).
About 0,000 is better, and about 5oo to 20,000 is more preferable.

(a) In the resin, 0.01 to 20 mol per kg of α, β-unsaturated unsaturated nylbonyl base resin, more preferably 0
．． It is appropriate that the amount is within the range of 1 to 5 mol, and (
b) The primary or secondary hydroxyl group in the resin is suitably present in an amount of 0.01 to 50 mol, more preferably 0.1 to 10 mol, per Ikg of resin. Further, the resin (a) may have a hydroxyl group in the resin.

The curing catalyst (c) in the present invention includes alkali metal hydroxides, alkaline earth metal hydroxides, quaternary ammonium bases, quaternary phosphonium salts, tertiary sulfonium groups, and hydroxides thereof. At least one of the following can be used: 111 organic acid salts, and alkali metal alkoxides.

Examples of alkali metal hydroxides include sodium hydroxide, potassium hydroxide, and lithium hydroxide, and examples of alkaline earth metal hydroxides include calcium hydroxide and magnesium hydroxide.

Examples include barium hydroxide.

The above quaternary ammonium base, quaternary phosphonium 1
As 314 and the tertiary sulfonium IMm, those represented by the following general formula can be used.

R, -N@-R,OHe R, -P@-R,OHe ■ R+ -3e oHe [In these formulas, R,, R2, R3 and R4 are
The same or different hydrogen or an organic group having 1 to 14 carbon atoms, and at least one of R1, R2 and R3 is an organic group having 1 to 14 carbon atoms. In addition, these R, and R2 or R,, R2 and R3 may be taken together to form a heterocyclic cation with the nitrogen atom, phosphorus atom or sulfur atom to which they are bonded.] R,, The organic groups having 1 to 14 carbon atoms represented by R2, R, and R4 are not particularly limited as long as they do not substantially interfere with the ionization of ammonium bases, phosphonium bases, or sulfonium bases, such as hydroxyl groups, alkoxy A hydrocarbon group having 1 to 14 carbon atoms which may contain a heteroatom such as an oxygen atom in the form of a group is generally used.

Examples of such hydrocarbons include alkyl groups, cycloalkyl groups, cycloalkylalkyl groups, arylno, (and aralkyl groups, etc.), aliphatic, alicyclic, or aromatic hydrogen ↓ The alkyl group may be either linear or branched and has 8 or less carbon atoms, preferably a lower one, such as methyl, ethyl, n'''' or is.

-propyl, n+, 1so-1sec- or ter
Examples include t-butyl, pentyl, heptyl, and octyl groups. The cycloalkyl group or cycloalkylalkyl group preferably has 5 to 8 carbon atoms, and includes, for example, cyclopentyl, cyclohexyl, cyclohexylmethyl, cyclohexylethyl, and the like. The aryl group below includes phenyl, tolyl, xylyl groups, and the like. In addition, as for ti,
A benzyl group is preferred.

Preferred examples of IR hydrogen atoms, ti, containing a heteroatom 1, such as an oxygen atom, include a hydroxyalkyl group (especially a hydroxy lower alkyl group), specifically hydroxymethyl, hydroxyethyl, hydroxybutyl, hydroxypentyl , hydroxyheptyl, hydroxyoctyl groups, etc., alkoxyalkyl groups (especially lower alkoxy lower alkyl groups), specifically methoxymethyl, ethoxymethyl, ethoxyethyl, n-propoxyethyl, 1so-propoxymethyl, n-butoxymethyl, Examples include 1so-butoxyethyl and tert-butoxyethyl groups.

R2 and R3 or R2, R3 and R4 together,
Examples of -WΦ in the case where these are heterocyclic groups formed together with the nitrogen atom, phosphorus atom or sulfur atom to which they are bonded include those shown below.

As the curing catalyst (C) of the present invention, organic acid salts of these hydroxides and bases, as well as alkali gold and alkoxides can be used. As the organic acids used to form the organic acid salts, formic acid, acetic acid, lactic acid, trimethylacetic acid,
Organic acids such as acrylic acid, methacrylic acid, chloroacetic acid, hydroxyacetic acid, crotonic acid, maleic acid monomethyl ester, fumaric acid monoethyl ester, and itaconic acid monomethyl ester can be used. Among these, those having a dissociation constant (pKa ifi) of lXl0-' or less are particularly preferred. Typical examples of alkali diabetic alkoxides include sodium ethoxide, sodium methoxide, potassium methoxide, and potassium ethoxide.

In undeveloped IJI, the blending amount of (C) ri31i catalyst is relative to the total amount of (a) resin and (b) resin.

A preferable range is from o, ooi to 30%.

The curable resin composition comprising (a) resin, (b) resin, and (C) curing catalyst of the present invention may include, depending on the cost,
Color pigments 1 extender pigments, anti-rust pigments, other leveling agents,
Various additives such as antifoaming agents and anti-sagging agents may be added.

The curing method of the present invention comprises (a) resin and (b) resin (
C) It is characterized by being cured by heating in the presence of a curing catalyst, and the heating conditions are as follows:
Suitable temperature is 60 to 200°C, more preferably 100 to 160°C for 5 to 120 minutes, more preferably 10 to 30 minutes.

[Actions and Effects of the Invention] The present invention provides a resin having an α,β-unsaturated carbonyl group, a resin having a primary or secondary hydroxyl group without an α,β-unsaturated carbonyl group, and a specific resin. In combination with a curing catalyst, the addition reaction of hydroxyl groups to saturated groups occurs at a relatively low temperature, and this addition reaction does not generate by-products and does not cause yellowing of the coating, which is an excellent effect. Express. Moreover, the composition of the present invention has good storage stability;
Moreover, when used as a paint, it has features such as excellent smoothness of the coated surface obtained, and is suitable for use as a composition for seedlings, especially as a paint.

Fruit” 1 case The present invention will be further clarified with reference to Examples below.

In addition, "1 part" and "%" respectively refer to
``section'' means ``% by weight''.

The mixture of Synthesis Example 1 was added dropwise over 3 hours into a four-hole flask containing 1000 parts of toluene and maintained at 120°C. Thereafter, it was aged at 120°C for 5 hours.

Further, this was added and reacted at 120°C, and the end point was the point at which the acid value became 1 or less. The resulting resin solution has a nonvolatile content of 50.0
%, Gardner viscosity (25°C) H. The peak molecular weight of this resin by GPC was about 25,000.

Four pieces of Synthesis Example 2 were added into a flask, and the reaction was carried out at 100° C. The end point was when the acid value became 0. The resulting resin solution had a nonvolatile content of 49.7% and a Gardner viscosity (25° C.) of H. The peak molecular weight of this resin by GPC is approximately 100.
It was 0.

Four pieces of Synthesis Example 3 were added into 11 flasks, and dehydration condensation was carried out at 200°C, and the point at which no water came out was defined as the end point. , then 1252 parts of butyl acetate was added.

1; The resin solution obtained had a nonvolatile content of 50.2% and a Gardner viscosity (25°C) of Q. The peak intermolecularity of this resin by GPC was approximately 3,500.

Four pieces of Synthesis Example 4 were added into a Lof flask, and the reaction was carried out at 70°C, and the end point was when the N00 value reached 38. After that, the reaction was carried out at 80° C., and the end point was the point where the N00 value became 1 or more. The resulting resin solution had a nonvolatile content of 49.8% and a Gardner viscosity (25° C.) of Z.

The peak molecular weight of this resin by GPC was about 2000.

(Note 1) Plaxel #308: ε-caprolactone type 3
A functional polycaprolactone polyol resin with a weight average molecular weight of 1280 and a hydroxyl value of 198 (Daicel Chemical Industry ■
product).

The mixture of Synthesis Example 5 was added dropwise over 3 hours into a four-bottle flask containing too much toluene and maintained at 1200C. Thereafter, it was aged at 120°C for 5 hours.

The resulting resin solution had a nonvolatile content of 50.0% and a Gardner viscosity (25° C.) of 0. The peak molecular weight of this resin by GPC was about 30,000.

Synthesis Example 6 was added into 4 + 1 flasks and reacted at 100°C for 1 hour.

1! The resin solution thus obtained had a nonvolatile content of 49.7% and a Gardner viscosity (at 25° C.) of ■. The peak molecular weight of this resin by GPC was about 1000.

Four samples of Synthesis Example 7 were placed in a spherical flask and subjected to dehydration condensation at 200°C, and the end point was when WAhlli became 10 or less.

after that 1906 parts of butyl acetate was added.

The resulting resin solution had a non-volatile content of 50.5% and a Gardner viscosity (25°C) of M. The peak molecular wall of this resin by GPC was about 5,000.

Example 1 100 parts of the resin solution obtained in Synthesis Example 1 (50 parts of resin solid content)
1. 100 parts of the resin solution obtained in Synthesis Example 5 (resin solid content: 50 parts) and 1 part of potassium hydroxide were mixed uniformly, and this was coated on a glass plate to a dry film thickness of about 20 microns. The bake was cured in a dryer at 140° C. for 30 minutes. The acetone extraction residue, water resistance, and storage stability of the paint film on this painted board were investigated. The test results are shown in Table 1.

Examples 2 to 13 and Comparative Examples 1 to 3 The compositions shown in Table 1 were mixed and coated in the same manner as in Example 1, and baked under the following conditions.

Examples 1, 2.10, 11, 12.13 and Comparative Example 1
~3...140°C x 30 minutes, Examples 3-5...
...140℃XIO minutes, Example 6.7...
120°C x 30 minutes, Example 8.9...100°C
×10 minutes.

The test results are shown in Table 1.

Notes in Table 1 are as shown in double digits.

(Note 2) Compound A: CH3 CH3-N@-CH30He CH.

(Note 3) Compound B: CH3CH2-3e OH CH.

(Note 4) Compound C: (Note 5) Compound D= It is.

(Note 6) Storage stability: An evaluation of 0 means that extreme thickening and gelation do not occur (140) Kansai Paint Co., Ltd. Procedural Amendment (July 2, 1988 1. Indication of the case Patent Application No. 326024 of 1985 2. Name of the invention Curable resin composition and curing method 3. Person making the amendment Relationship to the case Applicant Address 33-1 Kanzaki-cho, Amagasaki City, Hyogo Prefecture Title name (
140) Kansai Paint Co., Ltd. Representative Yama 1) Hajime
34. Number of inventions increased by amendment 05. Detailed explanation of the invention in the specification to be amended 6, Contents of amendment Formula on line 14 % Formula % 0 Specification, page 8, formula on line 15 `` 1・ 1 ○ Correct the formula on page 9, line 1 of specification.

Next to the 14th line of the 12th page of the O specification, add the following statement on a new line.

r In the present invention, the blending ratio of resin (a) and resin (b) is solid content weight ratio, and resin (a) is 99.99 to 50.
The range of weight % is preferable, the range of 99.9 to 70 weight % is more preferable, and the range of resin (b) is preferably 0.01 to 50 weight %, and the range of 0.1 to 30 weight % is more preferable. . ”

Claims (2)

[Claims] (1) (a) Resin having α,β-unsaturated carbonyl group, (b) Primary or secondary resin having no α,β-unsaturated carbonyl group
(c) an alkali metal hydroxide, an alkali metal organic acid salt,
Alkaline earth metal hydroxide, alkaline earth metal organic acid salt, quaternary ammonium base, quaternary ammonium organic acid salt, quaternary phosphonium base, quaternary phosphonium organic acid salt, tertiary sulfonium base, A curable resin composition comprising a tertiary sulfonium organic acid salt and at least one curing catalyst selected from alkali metal oxides. (2) (a) A resin having an α,β-unsaturated carbonyl group, and (b) a resin having no α,β-unsaturated carbonyl group and having a primary or secondary hydroxyl group, and (c) an alkali metal water. oxides, alkali metal organic acid salts,
Alkaline earth metal hydroxide, alkaline earth metal organic acid salt, quaternary ammonium base, quaternary ammonium organic acid salt, quaternary phosphonium base, quaternary phosphonium organic acid salt, tertiary sulfonium base, A curing method characterized by curing by heating in the presence of at least one curing catalyst selected from a tertiary sulfonium organic acid salt and an alkali metal oxide.