JPH0320427B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a resin composition for coatings, and more particularly, the present invention relates to a resin composition for coatings, and more particularly, it contains a specific fatty acid-modified vinyl copolymer and a functional group-containing vinyl copolymer as essential components, or a specific crosslinking agent (C) component. The present invention also relates to a resin composition which provides a coating film with excellent adhesion and gloss. An example of adding a fatty acid to a glycidyl group-containing vinyl copolymer is a method of obtaining an air-curing resin using a drying oil fatty acid. When using polymers, the use of vinyl monomers having functional groups such as carboxyl groups, phosphoric acid groups and/or amino groups, which are said to have a great effect on imparting adhesion to the coating film, is important during polymerization. The fact is that it is completely inappropriate because it reacts with glycidyl groups and gels, and it is impossible to introduce functional groups by such means. On the other hand, such functional groups, especially those having two or more carboxyl groups, phosphoric acid groups and/or amino groups, improve wettability with pigments, but they also have a high ability to adsorb pigments to resins. However, as mentioned above, since vinyl monomers having such functional groups cannot be polymerized, so-called fatty acid-modified vinyl is produced by adding a fatty acid to a glycidyl group-containing vinyl copolymer. Copolymers inevitably have poor adhesion and gloss. However, as a result of various studies in view of the current situation, the inventors of the present invention have found that a product with excellent adhesion and gloss,
In addition, the present invention was completed by discovering a resin composition for paint that has excellent physical and chemical properties as well. That is, the present invention uses 0 to 60% by weight of styrene;
Preferably 10 to 50% by weight, glycidyl acrylate, glycidyl methacrylate, β-methylglycidyl acrylate and/or β-methylglycidyl methacrylate [hereinafter collectively referred to as (β-methyl)glycidyl (meth)acrylate” . ], preferably 70 to 5% by weight, and 5 to 97% by weight of other vinyl monomers copolymerizable with these monomers,
Preferably, glycidyl and/or β-methylglycidyl groups obtained by copolymerizing up to 85% by weight [hereinafter, these will be collectively referred to as (β-methyl)glycidyl groups for short. ] A fatty acid-modified vinyl copolymer (A) obtained by adding a fatty acid having an iodine value of 30 to 200 to 100 parts by weight of the vinyl copolymer containing the polyester, and a vinyl copolymer selected from the group consisting of a carboxyl group, a phosphoric acid group, and an amino group. A vinyl copolymer (B) having at least one functional group such as The present invention provides a resin composition for coating material which also contains a resin or an isocyanate prepolymer (C). Since the composition of the present invention is a mixture of a fatty acid-modified vinyl copolymer (A) and a functional group-containing vinyl copolymer (B), it provides a coating film with excellent adhesion and gloss. Furthermore, if necessary, amino resin or isocyanate prepolymer (C) can also be blended, making it possible to create a three-dimensional structure, and the result is a coating film with excellent physical and chemical properties. It gives Here, typical fatty acids mentioned above include those obtained from natural oils such as linseed oil, tall oil, safflower oil, soybean oil, castor oil, rice bran oil, dehydrated castor oil, or Chinese tung oil; ) 200 and 300 (produced by Hercules Co., Ltd. in the United States), these can be used alone or in combination of two or more so that the total iodine value falls within the range of 30 to 200. By doing so, it is possible to prevent the negative effects such as fading of the paint film when using a material with a high iodine value, and conversely, it is also possible to improve the advantages such as hardenability. They should be selected and decided accordingly. The amount of the fatty acid used is 5 parts by weight per 100 parts by weight of the (β-methyl)glycidyl group-containing vinyl copolymer.
If the amount is less than 190 parts by weight, the effect of the present invention cannot be expected because fatty acid modification has little effect on the flexibility and hardness of the coating film, and conversely, if it exceeds 190 parts by weight, the high iodine value When using , the resulting coating film is poor in flexibility and brittle due to crosslinking due to oxidative polymerization of the unsaturated bonds and further crosslinking due to the crosslinking agent component (C), and both cannot be used for practical use. Become something. In addition, when mixing saturated fatty acids to reduce the iodine value, even if crosslinking with the curing agent component (C) is used to ensure the coexistence of unsaturated bonds,
Due to the uneven distribution of crosslinking points, it becomes difficult to satisfy both hardness and flexibility at the same time, and overall coating film performance is only obtained in one direction.
Such measures are not appropriate. In the above-mentioned (β-methyl)glycidyl group-containing vinyl copolymer, if styrene is used in an excessively large amount exceeding 60% by weight, the resulting copolymer (A) itself will inevitably have poor weather resistance. Therefore, the appropriate amount of styrene to be used is within 60% by weight, preferably in the range of 10 to 50% by weight, and (β-methyl)glycidyl (meth)
In acrylate, the (β-methyl)glycidyl group reacts with fatty acids, so the amount of the monomer used is determined depending on the amount of fatty acid used, but the reaction rate and the coating film of the remaining (β-methyl)glycidyl groups are In terms of the adverse effect on the fatty acid, it is preferable that the amount is 1.0 to 1.25 equivalents of (β-methyl)glycidyl group per equivalent of carboxyl group in the fatty acid, and the amount of other vinyl monomers is preferably 5 to 97% by weight. can be used up to 85% by weight. Typical examples of other vinyl monomers copolymerizable with (β-methyl)glycidyl (meth)acrylate and/or styrene include C ₁
Alkyl (meth) with an alkyl group of ~ _C18
Olefinic or vinyl ester monomers such as acrylate, (meth)acrylonitrile, perfluoroalkyl group or fluoroalkyl group-containing vinyl monomer, vinyl chloride, vinylidene chloride, vinylidene fluoride, chlorotrifluoroethylene, or vinyl acetate, respectively. There are monomer-like ones such as , and polymer-like ones such as alkyd resins or polyester resins that have copolymerizable unsaturated bonds in the molecule.
When using such a polymeric material as a monomer, the amount used is selected within a range that does not result in gelation even if the (β-methyl)glycidyl group in the resulting copolymer reacts with the carboxyl group in the monomer. It goes without saying that it should be done. As such other copolymerizable vinyl monomers, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, or hydroxyethyl vinyl ether can also be used, but these The amount of hydroxyl group and (β
It goes without saying that it should be selected within a range that does not result in gelation even if it reacts with the -methyl)glycidyl group. On the other hand, the above-described functional group-containing vinyl copolymer (B) includes carboxyl group-containing vinyl monomers such as (meth)acrylic acid, crotonic acid, itaconic acid, or fumaric acid, 2-(meth)acryloyloxyethyl acid, etc. Phosphate group-containing vinyl monomers such as phosphate or 2-(meth)acryloyloxypropyl acid phosphate, and/or amino group-containing vinyl monomers such as dimethylaminoethyl (meth)acrylate or diethylaminoethyl (meth)acrylate. Typical examples are those obtained by copolymerizing the above-mentioned monomer-like or polymer-like copolymerizable vinyl monomers, hydroxyl group-containing vinyl monomers, etc., but also various hydroxyl group-containing vinyl copolymers. Of course, those obtained by adding P ₂ O ₅ to can also be used as the phosphoric acid group-containing vinyl copolymer. The method for preparing the fatty acid-modified vinyl copolymer (A) and the functional group-containing vinyl copolymer (B) described above is not particularly limited, and various methods such as solution polymerization and bulk polymerization may be used. Although this is possible, for the purposes of the present invention, it is best to use solution polymerization because it is easy to form into a paint and the molecular weight can be easily controlled. The respective copolymers (A) and (B) thus obtained have a solid content weight ratio of (B)/(A)=1/99.
It is appropriate to use a range of ~80/20. If this (B)/(A) ratio is smaller than 1/99, the absolute amount of copolymer (B) will decrease. Even if the ratio is larger than 80/20, the effect on adhesion and gloss will be extremely small and the purpose of the present invention cannot be met.On the other hand, if this ratio is larger than 80/20, the As the absolute amount decreases, even if a copolymer (A) with a large amount of fatty acids is used, the characteristics of modification with fatty acids such as air curability and flexibility of the coating film cannot be expected. This would no longer meet the purpose of the present invention. In the present invention, a resin composition that satisfactorily achieves the object of the present invention can be obtained by simply mixing these copolymers (A) and (B), but the present invention further provides a crosslinking agent (C) component. The present invention also provides resin compositions that also incorporate amino resins or isocyanate prepolymers. By the way, the copolymer (A) already contains hydroxyl groups generated by the reaction between fatty acids and (β-methyl)glycidyl groups, and the copolymer (B) also contains vinyl containing hydroxyl groups. When a monomer is also used, sufficient crosslinking and curing can be achieved with the hydroxyl groups derived from the monomer. The necessity of the crosslinking agent (C) component should be determined accordingly. Here, typical isocyanate prepolymers include a trimer of hexamethylene diisocyanate, a trimethylolpropane adduct of hexamethylene diisocyanate, and a trimethylolpropane adduct of tolylene diisocyanate. , normal 2
Of course, any of those used in liquid urethane paints can be used. The amount of the prepolymer to be blended is determined by the equivalent ratio of OH/NCO=1/with respect to the total hydroxyl groups of the copolymer (A) and the copolymer (B).
A suitable range is 0.3 to 1/1.5, preferably 1/0.5 to 1/1.2. NCO per equivalent of OH
If NCO is less than 0.3 equivalent, it is difficult to obtain the effect of blending the isocyanate prepolymer, while on the other hand, if NCO exceeds 1.5 equivalent,
Inevitably, foaming tends to occur under high humidity conditions, and in addition, it is not preferable from the viewpoint of paint cost. On the other hand, typical amino resins include etherified products obtained by reacting one or more amino compounds such as melamine, urea, or benzoguanamine with formaldehyde or an equivalent substance; They may be used alone or in combination. The amount of the amino resin blended is within the range of 10 to 30% by solid weight based on the total amount of the copolymer (A) and copolymer (B), which is effective from the viewpoint of coating film performance. However, the amount of such amino resin is determined by taking into consideration the amount of hydroxyl groups in the copolymers (A) and (B), the type of the amino resin, the required coating performance, etc. Therefore, the present invention is not limited only to the above range. However, the amount of the amino resin used is 5
If it is less than 40% by weight, it will be difficult to obtain the effect of the resin formulation, and if it exceeds 40% by weight, the coating film will inevitably become brittle. , undesirable. Therefore, in general, it is appropriate that the amount be in the range of 5 to 40% in terms of solid content weight, based on the total amount of copolymer (A) and copolymer (B). In addition, the fatty acid-modified vinyl copolymer (A)
As mentioned above, it can be obtained by synthesizing a (β-methyl)glycidyl group-containing vinyl copolymer by solution polymerization according to a conventional method and then adding a fatty acid. The temperature of both reactions and the catalyst for the addition reaction are not particularly limited, but in the polymerization reaction, they may be in the range of approximately 60 to 140°C, which is the polymerization temperature of ordinary vinyl monomers. In the case of an addition reaction, the temperature may be set at a higher temperature than during the polymerization reaction to promote the reaction, and in this case, a conventional addition reaction catalyst may be used to promote the reaction. As the solvent used for each of the above-mentioned copolymers (A) and (B), commonly used solvents can be used as they are depending on the type of each copolymer, but only the most representative ones are used. Examples include aromatic solvents such as toluene and xylene; ester solvents such as ethyl acetate and n-butyl acetate; alcohol solvents such as methanol and n-butanol; or ketone solvents such as methyl ethyl ketone and methyl isobutyl ketone. Aliphatic solvents such as mineral spirits can also be used, and the amount of such solvent used also depends on the amount of fatty acid used for the addition reaction and (A)
(B) Since it depends on the composition of each copolymer, it is not uniform and should be determined based on these dependent factors. The curing conditions for the composition of the present invention are not uniform, as there are various curing methods such as curing at room temperature or hardness by heating, and appropriate curing temperatures. Should be selected. Next, the present invention will be described with reference to Reference Examples, Examples, and Comparative Examples, in which all parts and percentages are based on weight unless otherwise specified. Reference Example 1 [Preparation example of fatty acid-modified vinyl copolymer (A)] In a four-necked flask equipped with a thermometer, reflux condenser, nitrogen gas inlet, and stirrer, 1000 parts of xylene and di-t-butyl peroxide ( DTBPO)
Styrene (St) 200 parts Methyl methacrylate (MMA) 300 n-Butyl methacrylate (n-BMA)
200〃 n-butyl acrylate (n-BA) 200〃 glycidyl methacrylate (GMA) 100 parts azobisisobutyronitrile (AIBN) 10〃 t-butyl perbenzoate (TBPB) 4〃 was added dropwise over 4 hours, and then 12 After continuing the reaction for several hours and confirming that the non-volatile content (NV) had reached 50.9%, 200 parts of soybean oil fatty acid was added, the temperature was raised to 150℃, and the reaction was continued at the same temperature until the acid value reached around 2. After that
After adding 200 parts of xylene, NV is 50.3%, viscosity (Gardner; same below) is Z, hydroxyl value is 14.9,
A transparent resin solution with a color number of 1 and an acid content of 1.8 was obtained. Reference Example 2 [Same as above] In a flask similar to Reference Example 1, 979 parts of turpentine and 2 parts of DTBPO were charged, the temperature was raised to 120°C, and St.
480 copies, MMA 200 copies, n-BA 20 copies, GMA
250 parts of "Betsukosol P-470-70" [long oil alkyd resin manufactured by Dainippon Ink and Chemicals Co., Ltd.], 71 parts of
10 parts of AIBN, 5 parts of t-butylperoxy-2-ethylhexanate (TBPO) and TBPB
3 parts of the solution were added dropwise over 5 hours, and the reaction was continued at the same temperature for 4 hours after the addition, resulting in an NV of 48.1%.
When a glycidyl group-containing vinyl copolymer solution was obtained which was wax-like when cold and was insoluble in turpentine,
150 parts of dehydrated castor oil fatty acids, 150 parts of soybean oil fatty acids
After adding 100 parts of coconut oil fatty acid and 0.4 parts of 2-methylimidazole (2-MIZ) and reacting at 130°C until the acid value reached around 2, 400 parts of turpentine was added and the NV was 50.8% and the viscosity was S-T, acid value is 1.5,
A transparent resin solution with a color number of 2 was obtained. Reference Example 3 [Same as above] In a flask similar to Reference Example 1, 600 g of xylene was added.
1 part, 300 parts of n-butyl acetate (n-BuAC) and 2 parts of BTBPO were charged, the temperature was raised to 125°C, and St.
350 copies of , 90 copies of MMA, 170 copies of n-BMA, n
- 100 parts of BA, 130 parts of β-hydroxyethyl methacrylate (β-HEMA), 60 parts of β-methylglycidyl methacrylate (MGMA),
10 parts of AIBN, 10 parts of TBPO, and 4 parts of TBPB were added dropwise over 5 hours, and the reaction was continued for 8 hours at the same temperature after the addition, and after confirming that the NV was 49.0%, the soybean oil fatty acid 100 copies and 2-MIZ
Add 0.1 part and react at the same temperature until the acid value is around 1.2, then add 100 parts of xylene to increase the NV.
A transparent resin solution having a viscosity of 49.9%, a viscosity of Z ₂ , a color number of 2, an acid value of 1.1, and a hydroxyl value of 25.8 was obtained. Reference Example 4 Into a flask similar to Reference Example 1, 1000 parts of turpentine and 2 parts of DTBPO were charged, and the temperature was raised to 125°C.
200 copies of St, 200 copies of MMA, 600 copies of GMA,
10 parts of AIBN, 10 parts of TBPO, and 4 parts of TBPB were added dropwise over 6 hours, and the reaction was then continued at the same temperature for 10 hours to complete the reaction. The glycidyl group-containing vinyl copolymer solution obtained here was transparent when heated, but had no solubility at 25° C. and was in a cloudy state. Next, 1000 parts of soybean oil fatty acid and 200 parts of linseed oil fatty acid were added to this solution and reacted at 160°C until the acid value reached around 1, and then 466 parts of turpentine was added. The resin solution obtained here was transparent with an NV of 60.7%, a viscosity of Z, a color number of 2, and an acid value of 0.8. Reference Example 5 In a flask similar to Reference Example 1, add 1000 g of xylene.
1 part and 2 parts of DTBPO were charged and the temperature was raised to 125℃.
400 copies of St, 211 copies of n-BMA, 150 copies of n-BA
parts, 100 parts of acrylonitrile (AN), GMA
75 copies, 64 copies of β-HEMA, 10 copies of AIBN,
3 parts of TBPO and 4 parts of TBPB were added dropwise over 4 hours, and the reaction was continued for 12 hours at the same temperature. Then, 150 parts of linseed oil fatty acid and 0.1 part of boron trifluoride were added. After the reaction reached an acid value of around 1, 150 parts of n-BuAc was added until the NV was 49.9.
%, a viscosity of W, a color number of 6, and an acid value of 0.9. A transparent resin solution was obtained. Reference Example 6 [Preparation example of phosphoric acid group-containing vinyl copolymer (B)] In a flask similar to Reference Example 1, 600% of toluene was added.
and 400 parts of n-butanol, heated to 110℃, and added 200 parts of St, 200 parts of MMA, and 400 parts of n-BMA.
400 parts, 180 parts of n-BA, 20 parts of 2-acryloyloxyethyl acid phosphate, AIBN.
10 parts of P-O, 3 parts of P-O, and 2 parts of TBPB were added dropwise over 5 hours, and the reaction was continued for 10 hours at the same temperature, resulting in an NV of 50.1%, an acid value of 4.1, and a viscosity of T-
A transparent resin solution with U ² and a color number of 1 or less was obtained. Reference Example 7 [Preparation example of carboxyl group-containing vinyl copolymer (B)] In a flask similar to Reference Example 1, xylene 266
400 parts of n-BuAc and 2 parts of BTBPO were heated to 120°C, and 300 parts of St and 2 parts of n-BMA were charged.
400 parts, 120 parts of β-HEMA, 60 parts of methacrylic acid (MAA), 120 parts of lauryl methacrylate
15 parts of AIBN, 15 parts of TBPO, and 4 parts of TBPB were added dropwise over 6 hours, and then reacted at the same temperature for 10 hours. NV was 61.0%, viscosity was Z, acid value was 25.3, A transparent resin solution with a color number of 1 or less and a hydroxyl value of 30.1 was obtained. Reference Example 8 [Example of preparation of amino group-containing vinyl copolymer (B)] The same procedure as in Reference Example 7 was carried out except that the same amount of dimethylaminoethyl methacrylate was used instead of MAA, and the NV was 61.1% and the viscosity was Z. ₃ , a transparent resin solution having an acid value of 0.8, a color number of 4, and a hydroxyl value of 30.8 was obtained. Examples 1 to 6 and Comparative Examples 1 and 2 Each fatty acid-modified vinyl copolymer (A) obtained in Reference Examples 1 to 5 and each functional group-containing vinyl copolymer (B) obtained in Reference Examples 6 to 7 ) in the proportions shown in Table 1, titanium oxide was added so that the PWC was 30%, the mixture was kneaded in a sand mill for 1 hour, and then a dryer was added while crosslinking agent (C) In the case of blending, the viscosity was adjusted with thinner to give a coating composition of 20 seconds using a food cup No. 4 after adding it here to obtain a coating composition. In this case, the above dryer is made of cobalt naphthenate with a metal content of 6%, and cobalt naphthenate with a metal content of 6%.
A mixture of 24% lead naphthenate and 1:1 weight ratio was used. On the other hand, in Examples 1 and 4 and Comparative Example 1, the thinner used was toluene/xylene/methyl isobutyl ketone/ethyl acetate/n-BuAc/n-butanol = 35/35/10/5/10/5 (weight ratio). In Examples 2, 5 and Comparative Example 2, a mixture of "Swazol 1000" [aromatic solvent manufactured by Maruzen Sekiyu Co., Ltd.]/n-butanol/butyl cellosolve was used.
A mixed solution of 70/20/10 (weight ratio) was used, and in Examples 3 and 6, toluene/xylene/ethyl acetate/n-BuAc/cellosolve acetate = 20/
A mixed solution of 30/10/20/20 (weight ratio) was used. Thereafter, each of the paints thus obtained was separately sprayed onto an iron plate that had previously been coated with a primer, and then left to stand for 96 hours in Examples 1 and 4 and Comparative Example 1. 2, 5 and Comparative Example 2 were dried at 150°C for 30 minutes, and Example 3
and No. 6 were dried at 80°C for 30 minutes and then allowed to stand for 72 hours before examining the performance of each coating film. The results are summarized in Table 2.

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【table】

【table】

Claims (1)

[Claims] 1 0 to 60% by weight of styrene and 95 to 3% by weight of glycidyl acrylate, glycidyl methacrylate, β-methylglycidyl acrylate and/or β-methylglycidyl methacrylate
and 5 to 97% by weight of other vinyl monomers copolymerizable with these monomers to 100 parts by weight of a vinyl copolymer containing a glycidyl group and/or β-methylglycidyl group, A fatty acid-modified vinyl copolymer (A) obtained by adding 5 to 190 parts by weight of a fatty acid having an iodine value of 30 to 200, and at least one type selected from the group consisting of a carboxyl group, a phosphoric acid group, and an amino group. A resin composition for a paint, characterized in that a vinyl copolymer (B) having a functional group is mixed in a solid content weight ratio of (B)/(A) = 1/99 to 80/20. thing. 2 0-60% by weight of styrene and 95-3% by weight of glycidyl acrylate, glycidyl methacrylate, β-methylglycidyl acrylate and/or β-methylglycidyl methacrylate
and 5 to 97% by weight of other vinyl monomers copolymerizable with these monomers to 100 parts by weight of a vinyl copolymer containing a glycidyl group and/or β-methylglycidyl group, A fatty acid-modified vinyl copolymer (A) obtained by adding 5 to 190 parts by weight of a fatty acid having an iodine value of 30 to 200, and at least one type selected from the group consisting of a carboxyl group, a phosphoric acid group, and an amino group. A vinyl copolymer (B) having a functional group is mixed with the solid content weight ratio (B)/(A) = 1/99 to 80/20, and an amino resin or an isocyanate prepolymer ( A resin composition for paint, characterized in that it also contains C).