JPH0240102B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a coating resin composition, and more particularly to a composition comprising a hydroxyl group-containing polyester-modified acrylic resin and an isocyanate compound or an amino resin. Recently, the range of coating base materials has gradually expanded from metal bases such as iron to flexible materials such as plastics and rubber, and as a result, coatings on the latter materials have become extremely common. Furthermore, there is a demand for flexible covering materials or coating materials used therein. In this way, in order to obtain a coating material or coating material that provides a flexible cured coating film, acrylic polyols with a low glass transition point, polyhydric alcohols and polyhydric carboxylic acids are used as coating film-forming resin components. Polyester polyols obtained from the following are effective. However, although cured coatings obtained using such acrylic polyols with low glass transition points and isocyanate compounds or amino resins have flexibility, they do not have sufficient hardness and solvent resistance, and they are not compatible with polyester polyols. Cured coating films obtained using isocyanate compounds or amino resins do not have sufficient weather resistance or flexibility at low temperatures. As described above, it is unlikely that a cured coating film that satisfies all of the weather resistance, solvent resistance, and flexibility can be obtained from the coating resin composition having the above-mentioned combinations. However, the present inventors have developed a coating resin composition that can provide a cured coating film with excellent weather resistance, solvent resistance, and flexibility on flexible substrates such as plastics or rubber. As a result of intensive studies to obtain the desired results, it was discovered that a resin composition consisting of a specific polyester-modified acrylic resin, an isocyanate compound, and an amino resin was suitable for these purposes, and the present invention was completed. That is, the present invention uses hydroxyl groups obtained by polymerizing an acrylic monomer mixture (-2) in the presence of an ε-caprolactone-modified unsaturated polyester polyol (-1) having a hydroxyl value of 50 to 300. It is composed of a polyester-modified acrylic resin () containing a polyester-modified acrylic resin () and a curing agent component () consisting of an isocyanate compound (-1) or an amino resin (-2), and
-1) and the above monomer mixture (-2) is within the range of 10/90 to 90/10, and this monomer mixture (-2) is a hydroxyl group-containing acrylic monomer. 1 to 40 parts by weight, 30 to 99 parts by weight of (meth)acrylic ester excluding the hydroxyl group-containing acrylic monomer, and further 0 to 60 parts by weight of other copolymerizable monomers. , and a coating resin composition in which the total amount of these monomer mixtures (-2) is 100 parts by weight. The present invention will be explained in detail, but first, the above-mentioned 50 to 50
In order to prepare the ε-caprolactone-modified unsaturated polyester polyol (-1) having a hydroxyl group of 300, for example, a polyhydric alcohol and a polyhydric carboxylic acid are esterified, and further a monoepoxide or a diepoxide is esterified. Then, ε-caprolactone may be added to the resulting polyester polyol having an unsaturated bond, or ε-caprolactone may be added to a polyhydric alcohol in advance, and then a polyhydric carboxylic acid may be added, and then a monohydric carboxylic acid may be added. A method of esterifying epoxide or diepoxide may also be used. Here, typical polyhydric alcohols include ethylene glycol, 1,4-butanediol, 1,6-hexanediol, glycerin,
Examples include trimethylolpropane and pentaerythritol, but of course mixtures thereof may also be used.On the other hand, typical examples of the above-mentioned polycarboxylic acids include succinic acid, adipic acid, azelaic acid, sebacic acid, and decane-1. , 10-dicarboxylic acid, terephthalic acid, isophthalic acid or phthalic acid (anhydride), but these may of course be used in the form of a mixture. In addition to the above-mentioned compounds, as the acid component, α,β-unsaturated polycarboxylic acids such as itaconic acid, fumaric acid, or maleic acid can be used as the acid component to serve as a grafting point. There is no problem in using oils such as soybean oil, coconut oil, castor oil or tall oil, or fatty acids obtained from such oils, in combination with the above-mentioned compounds. Further, representative monoepoxides or diepoxides mentioned above include "Carduura E" (glycidyl ester of Versatellite acid manufactured by Schiel in the Netherlands) and "Epiclon 1050" (Dainippon Ink & Chemicals Co., Ltd.). There are compounds that are commonly used as epoxy resins, such as "Epicote 1001" (produced by Siel, Netherlands). Unsaturated polyester polyol (-1) modified with ε-caprolactone thus obtained
In order to prepare the above-mentioned hydroxyl group-containing polyester-modified acrylic resin () using
and by a known and commonly used method in a weight ratio of 10/90 to 90/10,
In this case, if the amount of polyester polyol (-1) used is lower than 10% by weight, solvent resistance will be insufficient, and conversely, if the amount used exceeds 90% by weight, the flexibility of the coating film will not be obtained. . Preferably, the weight ratio of both components is in the range of 20/80 to 80/20, particularly preferably in the range of 30/70 to 70/30. In addition, the composition of the acrylic monomer mixture (-2) is composed of 1 to 40 parts by weight of the hydroxyl group-containing acrylic monomer mixture and 30 to 99 parts by weight of the (meth)acrylic ester; Alternatively, other copolymerizable monomers may be used in an amount up to 60 parts by weight. What is necessary is to determine the composition ratio of the monomers. Such acrylic monomer mixture (-2),
The above-mentioned ε-caprolactone modified unsaturated polyester polyol (-1) is dissolved in an aromatic hydrocarbon solvent, an aliphatic hydrocarbon solvent, an ester solvent, or a ketone solvent, etc. and charged therein to generate radicals. By solution polymerization in the presence of a polymerization initiator, a hydroxyl group-containing polyester-modified acrylic resin (), which is the base resin composition of the composition of the present invention, can be obtained. It is not limited only to the method. Here, typical examples of the hydroxyl group-containing acrylic monomers include β-hydroxyethyl (meth)acrylate, β-hydroxypropyl (meth)acrylate, β-hydroxyisopropyl (meth)acrylate, and β-hydroxybutyl (meth)acrylate. Meta) acrylate, etc., and “Pracel FA”
monomer or FM monomer" (ε-caprolactone adduct monomer manufactured by Daicel Chemical Co., Ltd.), and typical examples of the above (meth)acrylic acid esters include methyl (meth)acrylate, (meth)acrylic acid ester, ) Ethyl acrylate, butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, (meth)
Examples of copolymerizable monomers include lauryl acrylate and cyclohexyl (meth)acrylate, and typical monomers that can be copolymerized include styrene, (meth)acrylonitrile, and vinyl acetate. , (meth)acrylic acid, fumaric acid, maleic acid, itaconic acid, or (methyl)glycidyl (meth)acrylate, etc., or a monomer having a functional group such as a glycidyl group is not allowed to be partially used in combination. Furthermore, esters of α,β-unsaturated polycarboxylic acids such as dibutyl fumarate, dimethyl maleate or dibutyl itaconate can be used as well, and (meth)acrylic acid amide or derivatives thereof can also be used. N-methoxymethyl (meth)acrylamide, etc., as well as monomers with basic nitrogen in the side chain such as dimethylaminoethyl (meth)acrylate, and mono(2
Monomers having a phosphoric acid group such as -methacryloyloxyethyl) acid phosphate can also be used. On the other hand, the second component (curing agent component) of the composition of the present invention
Examples of the isocyanate compound (-1) used in the crosslinking reaction with the hydroxyl group-containing polyester-modified acrylic resin () include diisocyanates such as tolylene diisocyanate or hexamethylene diisocyanate; Adducts with polyhydric alcohols such as
The reaction between moles and 3 moles of diisocyanates,
Reactive to active hydrogen, such as vinyl copolymers whose essential component is a monomer that has both a copolymerizable unsaturated bond and an isocyanate group in one molecule, such as isocyanate ethyl (meth)acrylate. Known and commonly used so-called prepolymers having a free isocyanate group can be used, and commercially available compounds (-1) include "Burnock D-750, DN-950".
(product of Dainippon Ink & Chemicals Co., Ltd.) or "Desmodeur N" (product of Bayer, West Germany)
and so on. In addition, typical examples of the crosslinking agent that is the amino resin (-2) include methylolization of an amino group-containing compound such as melamine, urea, or guanamine with an aldehyde such as formalin, followed by lower aliphatic There are alcohols that have at least two methylol groups etherified, and a typical commercially available product is ``Betscamine P''.
-138'', ``Super Betsucomin J-820'' (the above,
Dainippon Ink & Chemicals Co., Ltd. products), Cymel
300'' (product of American Cyanamid Company). In obtaining the composition of the present invention, the blending ratio of the base resin composition () and the crosslinking agent or curing agent component () varies depending on the type of the crosslinking agent or curing agent component (), but generally speaking It is as follows. That is, it is appropriate that the solid content weight ratio of the polyester-modified acrylic resin () to the amino resin (-2) is in the range of 90/10 to 60/40; and the isocyanate compound (-1) are suitably in a range such that the ratio of the number of hydroxyl groups in the former resin () to the number of isocyanate groups in the latter compound (-1) is 1/0.5 to 1/1.5. , flexibility and weather resistance are ensured at such a blending ratio. A cured coating film obtained using the coating resin composition of the present invention, which contains both the crosslinking agent or curing agent components listed above () and the base resin component consisting of the polyester-modified acrylic resin () as essential components. The composition of the present invention can be applied to a wide range of substrates because it is extremely flexible and has excellent flexibility and impact resistance, especially at low temperatures, as well as excellent weather resistance and solvent resistance. For example, it can be applied to not only paints for metal coatings, but also flexible materials such as plastics and rubber, as well as wood products and concrete products. Next, the present invention will be specifically explained using reference examples, working examples, comparative examples, applied examples, and comparative applied examples.
In the following, parts and percentages are as follows, unless otherwise specified.
All items shall be based on weight. Reference Example 1 (Preparation example of ε-caprolactone-modified unsaturated polyester polyol (-1)) Using 37.2 parts of trimethylolpropane, 38.0 parts of phthalic anhydride, 3 parts of maleic anhydride, and 25.3 parts of "Carduura E" These were subjected to an esterification reaction, and then 42.8 parts of ε-caprolactone was added for an addition reaction to obtain an ε-caprolactone-modified unsaturated polyester polyol having a hydroxyl value of 140. After that, this polyester polyol was
An ε-caprolactone-modified unsaturated polyester polyol solution having a nonvolatile content of 60.5% was obtained by dissolving the mixture in 1 part of xylene and 15.2 parts of methyl isobutyl ketone. Hereinafter, this will be abbreviated as resin (-1-1). Reference Example 2 (Same as above) An esterification reaction was carried out using 15.6 parts of trimethylolpropane, 36.8 parts of 1,3-butanediol, 9.9 parts of phthalic acid, 2 parts of maleic anhydride, and 51.1 parts of adipic acid. A solution of ε-caprolactone-modified unsaturated polyester polyol with a non-volatile content of 60.5% was obtained in the same manner as in Reference Example 1, except that xylene was used as the solvent for the resulting polyester polyol. Hereinafter, this will be abbreviated as resin (-1-2). Reference Example 3 [Hydroxyl group-containing polyester modified acrylic resin () and blocked isocyanate compound ()
Preparation example of a one-component coating resin composition consisting of] Instead of 29.3 parts of "Burnock DN-950",
A one-component coating resin composition was obtained in the same manner as in Example 1, except that 85 parts of "Takenate B-820NS" (blocked isocyanate compound manufactured by Takeda Pharmaceutical Co., Ltd.) was used. Ta. Reference Example 4 (Example of preparation of unsaturated polyester polyol containing no ε-caprolactone) Ester was prepared using 37.2 parts of trimethylolpropane, 38.0 parts of phthalic anhydride, 3 parts of maleic anhydride, and 25.3 parts of "Carduura E". A control unsaturated polyester polyol containing no ε-caprolactone and having a hydroxyl value of 263 was obtained in the same manner as in Reference Example 1, except that ε-caprolactone was not used at all. This control polyol was then diluted with 55% of xylene.
and 10.6 parts of methyl isobutyl ketone to obtain a control unsaturated polyester polyol solution with a nonvolatile content of 60.5%. Hereinafter, this will be abbreviated as resin ('-1-1). Example 1 50 parts of the resin (-1-1) obtained in Reference Example 1 and 60 parts of toluene were charged into a reactor equipped with a stirrer and a cooler, and the temperature inside the reactor was adjusted.
The temperature was raised to 100℃. Then, 7 parts of styrene, 40 parts of n-butyl methacrylate, 10 parts of n-butyl acrylate, and 13 parts of β-hydroxyethyl methacrylate are then added.
1.5 parts of azobisisobutyronitrile in 20 parts of toluene and di-
A solution containing 0.5 part of tertiary-butyl peroxide was added dropwise over 4 hours, and the temperature was kept at the same temperature for 10 hours, resulting in a non-volatile content of 50.4%.
%, a hydroxyl group-containing polyester-modified acrylic resin having a hydroxyl value of 98 (solid equivalent) was obtained. Hereinafter, this will be abbreviated as resin (-a). Afterwards, 100 parts of this resin (-a) was mixed with 65 parts of "Tiepeque R-820" (titanium oxide manufactured by Ishihara Sangyo Co., Ltd.), and the pigment was dispersed in a sand mill. Kamin L-
117-60'' (amino resin manufactured by Dainippon Ink & Chemicals Co., Ltd.) was added thereto and diluted with thinner to adjust the paint viscosity to obtain the intended resin composition for coating. Example 2 The amount of “Tiepeque R-820” used was 48 parts,
A coating resin composition was obtained in the same manner as in Example 1, except that 29.3 parts of "Burnok DM-950" was used instead of "Super Beckamine L-117-60". Examples 3 to 6 and Comparative Examples 1 and 2 Hydroxyl group-containing polyester modified acrylic resin (-b) and (- Acrylic resin ('-a) was prepared for comparison with c). Hereafter, each base resin component (-b), (-
Six types of coating resin compositions were obtained using the same formulations as in Example 1 and Example 2, respectively, except that 100 parts of each of c) and ('-a) were used. Comparative Example 3 The same amount of resin ('-1-1) obtained in Reference Example 4 was used instead of resin (-1-1), and the composition of the monomer mixture was changed to styrene. In the same manner as in Example 1, except that the amounts were changed to 10 parts of n-butyl methacrylate, 43 parts of n-butyl acrylate, 12.6 parts of n-butyl acrylate, and 4.4 parts of β-hydroxyethyl methacrylate, A control hydroxyl group-containing polyester-modified acrylic resin having a hydroxyl value of 98 and a nonvolatile content of 50.0% was obtained. Hereinafter, this will be abbreviated as resin ('-b). Thereafter, a control resin composition for coating was obtained in the same manner as in Example 1, except that this resin ('-b) was used instead of resin (-a). Comparative Example 4 A control resin composition for coating was prepared in the same manner as in Example 2, except that the resin ('-b) obtained in Comparative Example 3 was used instead of the resin (-a). I got it. Application Examples 1 to 3, Reference Application Example 1, and Comparative Application Examples 1 and 2 The various coating resin compositions obtained in Examples 1, 3, and 5, Reference Example 3, and Comparative Examples 1 and 3 were each separately, Spray paint on mild steel plate, then
Baking was performed at 140°C for 20 minutes. The coating properties of each of the obtained cured coatings were tested, and the results shown in Table 2 were obtained. Application Examples 4 to 6 and Comparative Examples 3 and 4 The various coating resin compositions obtained in Examples 2, 4 and 6 and Comparative Examples 2 and 4 were separately applied to polystyrene molded plates, and then 80% ℃
Force drying was performed for 20 minutes. When the coating performance of the obtained coating film was tested, the results shown in Table 3 were obtained.

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Claims (1)

[Claims] 1 () Obtained by polymerizing an acrylic monomer mixture (-2) in the presence of an ε-caprolactone-modified unsaturated polyester polyol (-1) having a hydroxyl value of 50 to 300, A resin composition comprising a polyester-modified acrylic resin having a hydroxyl group and an isocyanate compound (-1) or an amino resin (-2), the resin composition comprising the polyester polyol (-
1) and the above acrylic monomer mixture (-2)
The weight ratio of the acrylic monomer mixture (-
2) is copolymerizable with 1 to 40 parts by weight of a hydroxyl group-containing acrylic monomer, 30 to 99 parts by weight of an acrylic ester or methacrylic ester other than the above hydroxyl group-containing acrylic monomer, and other copolymerizable consisting of 0 to 60 parts by weight of a monomer, and
A coating resin composition characterized in that the total amount of these monomer compounds (-2) is 100 parts by weight.