JPH08253731A - Resin composition for coating material - Google Patents

Abstract

PURPOSE: To obtain a resin compsn. for a two-component polyurethane coating material which has a high solid content, a low viscosity, and a low solvent content. CONSTITUTION: This compsn. comprises a polyisocyanate component and a polyol component comprising 90-50wt.% vegetable-oil-modified polyester polyol having a hydroxyl value of 70-300mgKOH/g and 10-50wt.% polypropylene glycol or its deriv.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin composition for a two-component curing type urethane coating material, and more particularly to a resin composition for coating material useful as a coating material for woodwork aiming at high solidification.

[0002]

2. Description of the Related Art Conventionally, resin compositions for two-component curing type urethane coatings have been found to give coating films excellent in hardness, gloss, water resistance and solvent resistance, so that they can be applied to various materials such as metal, plastic and wood. A resin composition for a two-component curing type urethane coating, which is used for coating, and particularly uses a polyester polyol, is widely used because of its excellent image clarity and solvent dilutability. For example, as disclosed in Japanese Patent Laid-Open No. 4-63882, a resin composition for a two-component curing type urethane coating using a specific polyester polyol is known, and such a resin for a two-component curing type urethane coating is known. The composition contains a large amount of solvents such as toluene, ethyl acetate, butyl acetate, and acetone in terms of workability (low viscosity and good coatability), which can avoid adverse effects on the work environment and human body. It was not there.

In order to solve this drawback, a method of adding process oil instead of the above-mentioned diluent solvent or a method of adding castor oil (for example, JP-A-60-47074 and JP-A-61-26675). JP-A-61-26676
However, in the case of process oil, the physical properties of the coating film may be deteriorated and the oil may bleed, and in the case of castor oil, there is the same risk as process oil. In order to solve such a problem, it has been attempted to use a polyol obtained by previously reacting castor oil with a polyhydric alcohol (Japanese Patent Laid-Open No. 64-69671).

[0004]

However, in the technique disclosed in Japanese Patent Laid-Open No. 64-69671, there is no fear of deterioration of the physical properties of the coating film, bleeding of the oil, or great deterioration over time, but after mixing the two liquids. The pot life is very short,
A special painting machine is required, and it is not yet satisfactory.

[0005]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies to improve such drawbacks, and as a result, a polyester polyol (A) having a hydroxyl value of 70 to 300 mg KOH / g modified with vegetable oil (A) and polypropylene. A two-component curable resin composition for urethane coatings, which comprises a polyol or a derivative thereof (B) in a weight ratio (A) / (B) of 90/10 to 50/50 and a polyisocyanate component. However, it is suitable for so-called high solid type urethane paints that have a high solid content by reducing the addition amount of solvent without deteriorating the physical properties (coating strength, coating suitability, etc.) originally possessed by urethane paints. In addition, it is necessary to polish the paint required for woodworking (polishing the coating surface after painting to obtain surface smoothness and adhesion improvement) and to shrink and expand materials such as wood. Follow-up to the Paneling is good, and has led to found the completion of the present invention that it is particularly very useful in woodworking paint. The solid content in the present invention also includes polyol (reactive diluent) such as polypropylene glycol.

The present invention will be described in detail below. The hydroxyl value modified with the vegetable oil of the present invention is 70 to 300 mg KOH
/ G of polyester-based polyol (A) is vegetable oil,
A polyester-based polyol obtained by reacting a polybasic acid component and a polyhydric alcohol component, having a hydroxyl value of 70 to 3
It is the one of 00 mgKOH / g. Examples of the vegetable oil include castor oil, linseed oil, rice bran oil, coconut oil, soybean oil, and modified products thereof, and among others, castor oil is important,
It is preferable to use castor oil alone or in combination with other vegetable oils such as linseed oil, rice bran oil, coconut oil and soybean oil.

Examples of the polybasic acid component include aromatic polybasic acids such as isophthalic acid, phthalic anhydride, terephthalic acid, orthophthalic acid, 2,6-naphthalenedicarboxylic acid, azelaic acid, sebacic acid and isosebacine. Acid, oxalic acid, succinic acid, dodecanoic acid, dimer acid, tetrahydrophthalic acid, hexahydrophthalic acid, hexahydroisophthalic acid, hexahydroterephthalic acid,
Aliphatic polybasic acids such as glutaric acid, adipic acid, pimelic acid, uberic acid and the like, hydrogenated phthalic acid, and alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, among others, isophthalic acid, phthalic anhydride Adipic acid is preferably used.

Further, as the above-mentioned polyhydric alcohol component, ethylene glycol, neopentyl glycol, diethylene glycol, tetramethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, 2,3,4-trimethyl-1,3-
Pentanediol, 3-methylpentene-1,5-diol, 1,4-cyclohexanedimethanol, ethylene oxide or propylenoxide of bisphenol A or hydrogenated bisphenol A, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polybutylene glycol, 2 , 2-diethyl-1,
3-propanediol, 2-n-butyl-ethyl-1,
3-Propanediol, tricyclodecanedimethanol, cyclohexanedicarboxylic acid, cyclohexanedimethanol, cyclohexanediol, and other dihydric alcohol components; glycerin, trimethylolpropane, trimethylolethane, and other trihydric alcohol components; pentaerythritol, and other tetrahydric alcohol components. Examples of the alcohol component include glycerin and trimethylolpropane.

Polyester polyol (A) of the present invention
Is obtained by reacting the above-mentioned vegetable oil, polybasic acid component and polyhydric alcohol component, and the hydroxyl value thereof is required to be 70 to 300 mgKOH / g.
If the hydroxyl value is less than 70 mgKOH / g, the viscosity when used as a paint will be high, and conversely, the hydroxyl value will be 300 mgKOH / g.
If it exceeds g, the physical properties of the coating film are deteriorated, which is not suitable. The hydroxyl value is preferably 100 to 200 mgKOH / g, more preferably 130 to 170 mgKOH / g. In adjusting the hydroxyl value, it is possible to adjust the hydroxyl value within the scope of the present invention by adjusting the charged molar ratio of the raw materials or adopting the raw materials having different numbers of functional groups.

The method for obtaining the polyester polyol (A) having a hydroxyl value of 70 to 300 mgKOH / g modified with the vegetable oil of the present invention using the above vegetable oil, polybasic acid component and polyhydric alcohol component is not particularly limited. Not 1
It can be obtained by a known polyester-based polyol production method such as dehydration condensation, transesterification condensation, etc. under an inert gas atmosphere at 50 to 250 ° C., and at this time, the polybasic acid component (A2) and 1 mol of the vegetable oil (A1) and Although the charging ratio (equivalent) of the polyhydric alcohol component (A3) cannot be unconditionally stated, the charging equivalent of (A2) and (A3) per 1 mol of (A1) is 5 from the viewpoint of coating film physical properties and coating suitability. ~ 15 and 10
-25 (equivalent) is preferable, and (A1) 1 is more preferable.
(A2) is 8 to 12 (equivalent) and (A3) is 1 per mol
It is 5 to 20 (equivalent). The molecular weight of the polyester-based polyol (A) is 1000 in terms of number average molecular weight.
It is preferably from 3,000 to 3,000, more preferably from 1,200 to 2,000, and if the molecular weight is less than 1,000, the physical properties of the coating film will be deteriorated.

Examples of the polypropylene glycol or its derivative (B) used in the present invention include derivatives such as polypropylene glycol and polypropylene glycol alkylene oxide adducts. Among them, the molecular weight is preferably 300 to 2000, more preferably 400 to 1
200 polypropylene glycol or an ethylene oxide adduct of polypropylene glycol is preferably used. When the molecular weight is less than 300, the physical properties of the coating film are deteriorated, and conversely, when it exceeds 2000, the viscosity of the coating composition becomes too high, which is not preferable.

The blending weight ratio (A) / (B) of the polyester polyol (A) and polypropylene glycol or its derivative (B) must be 90/10 to 50/50, and the blending of (A) is required. If the amount is larger than the weight ratio, the physical properties of the coating film are deteriorated. Preferably, the blending weight ratio of (A) / (B) is 80/20 to 6
It is 0/40.

Next, examples of the polyisocyanate component mixed with the polyol component of the present invention include aromatic, aliphatic, cycloaliphatic, or alicyclic polyisocyanates or mixtures thereof, among which tris Diisocyanate (TDI), diphenylmethane diisocyanate (M
DI), polyphenylmethane polyisocyanate (crude MDI), modified diphenylmethane diisocyanate (modified MDI), xylylene diisocyanate (XD)
I), aromatic polyisocyanates such as hexamethylene diisocyanate (HMDI), trimer compounds of these polyisocyanates, and reaction products of these polyisocyanates and polyols are preferably used.

The mixing ratio of the polyol component and the polyisocyanate component is 1 as the ratio of the hydroxyl equivalent number in the polyol component and the isocyanate equivalent number in the polyisocyanate component.
The range of 00:60 to 100: 160 is preferable, and especially 1
It is preferable to set it in the range of 00:80 to 100: 120. The number of hydroxyl equivalents in the polyol component is 1
When the number of equivalents of isocyanate in the polyisocyanate component is less than 50, the cross-linking reaction between the polyol component and the polyisocyanate component becomes insufficient, and the rapid curing property of the coating film decreases, and the water resistance is , Acid resistance,
It is not preferable because the polishing property is deteriorated.

In the above curing reaction, a reaction catalyst is not usually used, but trimethylenebis (4
-Aminobenzoate), dimethylethanolamine,
Amines such as triethyleneamine, tetramethylpolymethylenediamine, tris (dimethylaminomethyl) phenol, tin octylate, tin naphthenate, cobalt naphthenate, zinc naphthenate, metal salts such as dibutyltin laurate, higher carboxylic acids It is also possible to use bismuth or the like.

The resin composition for paints of the present invention is useful as a so-called high solid type paint, and when used as the paint (at the time of coating), 20% by weight of a solvent having a boiling point of 120 ° C. or lower is used. Hereafter, preferably 5 to 15% by weight can be compounded, and the viscosity of the coating material at 20 ° C. is 20%.
The viscosity is preferably 0 to 2000 cps and the viscosity is 2
If it is less than 00 cps, it is difficult to secure a sufficient coating thickness, and if it exceeds 2000 cps, the coating workability is deteriorated, which is not preferable. More preferably 500-1200c
ps. Examples of the solvent having a boiling point of 120 ° C. or lower include ethyl acetate, isobutyl acetate, acetone, methyl ethyl ketone, toluene and the like, among which ethyl acetate and toluene are preferably used.

The resin composition for paints of the present invention is used as a two-component curing type urethane paint, and actually contains a paint main component containing a polyol component as a main component and a polyisocyanate component as a main component as described later. It consists of a two-component curing agent and is used for coating by mixing and stirring the two-component components. The above solvent can be blended with the main component of the coating material and / or the curing agent. It is possible to mix the main agent and the curing agent after mixing, but it is preferable to mix them with the coating main agent or the curing agent from the viewpoint of stability, workability and the like. In the present invention, the above-mentioned solvent compounding amount and viscosity may be applied after mixing and stirring the above two-component components (during coating).

When the resin composition for paints of the present invention is used as a paint, it is possible to mix and use various vehicle components in addition to the above-mentioned components unless the object of the present invention is violated. Aliphatic petroleum resin, aromatic petroleum resin, alicyclic petroleum resin, vinyl resin and the like can be blended, and further, clay, talc, iron oxide, titanium oxide, like other general paints, Zinc phosphate, zinc chromate,
Pigments such as strontium chromate, aluminum powder, mica powder, and carbon black, and various additives (precipitating agent, surface modifier, thickener, dispersant, etc.) can be added. When a coating material is prepared by blending the above-mentioned respective components, a conventional method for a two-component curing type urethane coating material which has been conventionally used can be used.

For example, a pigment component and other additives are blended with a polyol component and other resin vehicle blended as necessary, and the mixture is diluted with a solvent. G. Disperse with a disperser such as a mill or a roll mill, and then mix a reaction catalyst to prepare a coating material. The viscosity of the main paint is
It is preferable to adjust the viscosity to about 500 to 1500 cps / 20 ° C. in consideration of the viscosity when mixed with the polyisocyanate component and the application to the coating means. On the other hand, the polyisocyanate component is prepared by appropriately diluting it with a solvent as desired (however, at the time of coating, it contains 20% by weight or less of a solvent having a boiling point of 120 ° C. or less, and the viscosity of the coating composition at 20 ° C. is 500 to It is preferable to consider it to be 1200 cps), and then mix it with the above-mentioned paint base agent at the time of use, and paint the painted surface using a paint device such as an airless painter, brush, roller, iron, air spray, etc. The amount of application at this time can be determined by the type and purpose of the material to be coated (whether lower, middle, or top coating described later, inclination angle of coated surface, etc.)
Therefore, it cannot be said unequivocally, but 20 to 200 g in terms of solid content
It is preferably selected from the range of / m ² .

In the present invention, the material to be coated is not particularly limited, and examples thereof include wood, metal, plastic, leather, fibers, and the like. However, wood is the target in terms of abrasiveness and followability to the material to be coated. It is especially useful as a paint for woodwork. When used as a paint for woodworking, it can be used as an undercoat paint (primer, sealer) applied directly to a substrate, an intermediate paint applied in the middle, or a topcoat (topcoat) applied to the final surface. Can also be used.

[0021]

Since the resin composition for paints of the present invention uses a specific polyol component, it is possible to realize a two-component curing type urethane paint having a low viscosity and a high solid content, and particularly, as a high solid paint. It is useful.

[0022]

EXAMPLES The present invention will be described in more detail below with reference to examples. The terms "part" and "%" are based on weight unless otherwise specified. Production Example 1 Castor oil (A1) 0.776 mol, glycerin (A3) 1.
553 mol and 0.15 g of sodium formate were reacted at 260 ° C. under nitrogen blowing for 1 hour while removing generated water, then cooled to 100 ° C., 3.882 mol of phthalic acid (A2), trimethylolpropane (A3) 2 0.717 mol, 72 g of xylene, and 0.36 g of dibutyltin oxide were charged and reacted at 210 ° C. for 5 hours to remove produced water and xylene. Thus, a polyester polyol (AI) having a hydroxyl value of 158 mgKOH / g was obtained.

Production Example 2 Castor oil (A1) 0.543 mol, linseed oil (A1) 0.2
33 moles, 1.553 moles of glycerin (A3) and 0.15 g of sodium formate were reacted at 260 ° C. under nitrogen blowing for 1 hour while removing generated water, then cooled to 100 ° C., and phthalic acid (A2) 3.882. Mol, trimethylolpropane (A3) 2.717 mol, xylene 72 g, and dibutyltin oxide 0.36 g were charged and reacted at 210 ° C. for 5 hours to remove water and xylene. As a result, a polyester polyol (A-II) having a hydroxyl value of 146 mgKOH / g was obtained. Production Example 3 In Production Example 2, instead of linseed oil (A1), soybean oil (A
A polyester type polyol (A having a hydroxyl value of 145 mgKOH / g) was prepared in the same manner as in Production Example 2 except that 1) was used.
-III) was obtained.

Production Example 4 Polyester polyol (A-) having a hydroxyl value of 145 mgKOH / g was produced in the same manner as in Production Example 2 except that rice bran oil (A1) was used instead of linseed oil (A1). IV) was obtained. Production Example 5 In Production Example 2, coconut oil (A
A polyester type polyol (A having a hydroxyl value of 148 mgKOH / g) was prepared in the same manner as in Production Example 2 except that 1) was used.
-V) was obtained.

Production Example 6 0.2 mol of coconut oil (A1), 2.91 mol of glycerin (A3) and 0.15 g of sodium formate were blown with nitrogen at 260 ° C.
The reaction is continued for 1 hour while removing the produced water at 100
After cooling to ℃, 5.0 mol of phthalic acid (A2), 1.5 mol of propylene glycol (A3), 72 g of xylene and 0.36 g of dibutyltin oxide were charged and reacted at 210 ° C for 5 hours to remove water and xylene. did. As a result, a polyester polyol (A-VI) having a hydroxyl value of 54 mgKOH / g was obtained. Production Example 7 Castor oil (A1) 0.43 mol, glycerin (A3) 2.5
5 moles and 0.15 g of sodium formate were blown with nitrogen 26
The reaction was carried out at 0 ° C for 1 hour while removing the produced water, and then 1
After cooling to 00 ° C, 4.25 mol of phthalic acid (A2), 4.04 of trimethylolpropane (A3), 72 g of xylene,
Dibutyltin oxide (0.36 g) was charged and reacted at 210 ° C. for 5 hours to remove produced water and xylene. As a result, a polyester polyol (A-VI) having a hydroxyl value of 350 mgKOH / g was obtained.

Example 1 Polyester polyol (A-
I) 70 parts, 20 parts of polypropylene glycol (PPG) (B) having a molecular weight of 1200 and 10 parts of ethyl acetate (C)
Parts were added to prepare a polyol component. On the other hand, as a curing agent, the number of hydroxyl equivalents in the above polyol component is 100.
Then, a polyisocyanate component (TDI system having an NCO content of 13% and a solid content of 75%, trade name; Coronate L, manufactured by Nippon Polyurethane Industry Co., Ltd.) was prepared so that the number of isocyanate equivalents was 100. Next, by mixing the paint main agent (polyol component) and the curing agent, the solid content at the time of coating was about 83.7% (the content of ethyl acetate was about 1
A high-solid type two-component curing type urethane coating composition having a viscosity of 6.3% by weight) and a viscosity at 20 ° C. of 980 cps was obtained and evaluated as follows.

(Drying property) The drying property of the coating film after coating is determined by JIS
K 5400 5.8. It was tested according to the dryness test of. That is, the obtained paint was applied to a glass plate (size 100 mm
× was applied at 100 mm × 2 mm) spray coater (coating amount 250 g / m ^2: about in terms of solid content 209g / m ^2),
Immediately after coating, the coated surface was placed upward and placed in a constant temperature bath set at 20 ° C. to dry it, and the following evaluation was performed every 10 minutes. The evaluation method is JIS K 5400 5.8. (2,3)
According to the procedure above, firmly pinch the test piece with your thumb and forefinger, and rapidly rub the coated surface repeatedly with your fingertips, and observe the coated surface at that time, leaving dents, fingerprints, or scratches on the coated surface. If it was judged to be uncured, and if there were no dents or fingerprints on the coated surface and no rubbing marks, it was judged to be cured and dried, and the curing and drying time (minutes) was measured.

(Thickness of coating film) A coating material was applied to a glass plate in the same manner as the above-mentioned drying property, cured and dried at 20 ° C for 7 days, and then the coating film was peeled off to measure the thickness with a dial gauge type thickness meter. did. (Salt water spray) A coating is applied to a mild steel plate (size: 70 × 150 × 1 mm) that has been sandblasted in the same manner as the above drying property, and the coating is cured and dried at 20 ° C. for 7 days, and then the coating film is cross-cut. After the coating, the coated surface was sprayed with 5% salt water at 37 ° C. for 480 hours, and then the coated surface state was evaluated by a peeling and scoring tape test. The blister, peeling or scoring tape test in each of the above evaluations was performed according to the following determination methods.

Judgment Method The blister etc. were judged as follows. ○ −−− No blister or peeling, less than 2mm corrosion on cross-cut part △ −−− No blister or peeling, 2-5mm corrosion on cross-cut part × −−− Blistering or peeling occurred About 5mm square 1mm
After forming the interstices (25 pieces) at intervals and sufficiently adhering the tape to the coated surface, the tape was peeled off in the 180 ° direction and the remaining interstices were counted. (Painted state) The obtained paint is applied to plywood (size: 150
× 150 × 5.5 mm) and sandblasted mild steel plate (size: 70 × 150 × 1 mm) with a spray coating machine at a coating amount of 250 g / m ² (about 2 in terms of solid content).
The coating film was coated at a rate of 09 g / m ² ) and cured and dried at 20 ° C. for 7 days, and the surface smoothness of the coating film and the presence or absence of foaming were visually observed.

[0030] (abrasive) resulting paint China plywood: coating weight 250 g / m ² (about 209 g / m ² in terms of solid content) with (Size 0.99 × 0.99 × 5.5 mm) to spray coater
And then cure and dry at 20 ° C for 24 hours.
A 400 water resistant abrasive paper was used to perform 10 reciprocating polishing operations in a distance of about 100 mm, and the polished state was observed. (Cold heat followability) The obtained paint was applied to plywood (size: 15
0 × 150 × 5.5 mm) with spray coater 2
After 50 g / m ² was coated so as to (approximately 209 g / m ² in terms of solid content) was 24 hours curing dried at 20 ° C., 80
The operation of standing at 20 ° C. for 2 hours and immediately standing at −20 ° C. for 2 hours was repeated twice, and the state of the coating film (whether there was cracking, peeling, etc.) at that time was visually observed. The evaluation results are shown in Table 3.

Examples 2 to 7 and Comparative Examples 1 to 4 A coating base material was prepared in the same manner as in Example 1 using the polyester polyol (A) and polypropylene glycol or its derivative (B) shown in Tables 1 and 2. Then, a two-component curing type urethane coating material was obtained by mixing with a curing agent, and the same evaluation was performed. In addition, about Examples 5-6, it painted with the airless coating machine, and other than that, it painted with the spray coating machine like Example 1. The evaluation results are shown in Table 3.

[0032]

[Table 1] Polyester-based polyol (A) PPG (B) (A) / (B) Type OHV compounding amount Molecular weight Weight ratio of compounding amount (mgKOH / g) (part) (part) Example 1 AI 158 70 1200 20 77/23 〃 2 A-I 158 70 910 20 20 77/23 〃 3 A-I 158 80 400 400 15 89/11 〃 4 A-II 146 60 1200 1200 30 67/33 〃 5 A-III 145 70 1 200 77/23 6 A-IV 145 70 1200 20 20 77/23 7 Av -145 145 70 1200 20 77/23 Comparative Example 1 A-I 158 35 35 1200 55 39/61 2 A-I 158 88 1200 1200 298 / 2〃3A-VI547012002077 / 23〃4A-VII350701200120077 / 23 Note) OHV represents a hydroxyl value. PPG represents polypropylene glycol or a derivative thereof, only in Example 2, ethylene glycol modified polypropylene glycol (trade name; Newpol PL-910, manufactured by Sanyo Kasei Co., Ltd.) was used, and the other was unmodified polypropylene glycol. Using.

[0033]

[Table 2] Solvent (C) Isocyanate component paint solids paint viscosity type compounding amount type compounding amount (wt%) (cps / 20 ° C) (part) (part) Example 1 Ethyl acetate 10 L 71 83.7 980 〃 2 ethyl acetate 10 L 75 83.6 950〃 3 ethyl acetate 5 L 93 85.4 1200 1200〃 4 ethyl acetate 10 L 64 84.1 800〃 5 toluene 10 L 66 84.0 1050〃 6 toluene 10 L 66 0 1030 〃 7 Toluene 10 L / D 67 84.0 1000 Comparative Example 1 Ethyl acetate 10 L 59 84.5 620 〃 2 Ethyl acetate 10 L 77 83.5 20000 〃 3 Ethyl acetate 25 L 26 75.0 950 〃 4 Ethyl acetate 10 L 146 81.1 920 Note) L represents coronate L, D is trade name “Takenate D-204” ( A TDI system having an NCO content of 7.5% and a solid content of 50%, manufactured by Takeda Yakuhin Kogyo Co., Ltd. was used. The isocyanate component of Example 7 was a mixture of L / D = 8/2 (weight ratio). Represent

[0034]

[Table 3] Dryability Coating thickness Salt water sprayed coating state Polishability Cold heat followability (min) (μm) Blisters etc. Goggle Example 1 140 169 ○ 25/25 Good Good No abnormalities 〃 2 150 167 ○ 25 / 25 Good Good No abnormalities 〃 3 140 175 ○ 25/25 Good Good No abnormalities 〃 4 130 173 ○ 25/25 Good Good No abnormalities 〃 5 130 172 ○ 25/25 Good Good No abnormalities 〃 6 130 172 ○ 25/25 Good Good No abnormalities 〃 7 160 165 ○ 25/25 Good Good No abnormalities Comparative example 1 210 168 × 0/25 Yuzu skin poor Poor * 1 No abnormalities 〃 2 Spray painting not possible due to high viscosity 〃 3 170 150 ○ 25/25 Yuzu skin condition * 2 No abnormalities 〃 4 200 162 △ 20/25 Poor foaming * 3 No abnormalities ) * 1: Clogging occurred on the polishing paper, which hindered the polishing work. * 2: It took a lot of time and labor for polishing work to obtain a smooth surface. * 3: The coating film was hard and polishing work was difficult.

[0035]

EFFECT OF THE INVENTION Since the resin composition for paint of the present invention uses a specific polyol component, it is possible to realize a two-component curing type urethane paint having a low viscosity and a high solid content, and particularly a high solid paint. Is very useful, especially as a paint for woodworking.

Claims (5)

[Claims] 1. A hydroxyl value modified with vegetable oil is 70 to 3
00mgKOH / g polyester polyol (A)
And polypropylene glycol or its derivative (B), the weight ratio of (A) / (B) is 90/10 to 50/50.
And a polyisocyanate component, which is a resin component for paints. 2. The resin composition for coating according to claim 1, wherein the vegetable oil is at least one selected from castor oil, linseed oil, rice bran oil, coconut oil, soybean oil, and modified products thereof. Stuff. 3. The resin composition for coating according to claim 1 or 2, wherein the polypropylene glycol or its derivative (B) has a molecular weight of 300 to 2,000. 4. 20% by weight of a solvent having a boiling point of 120 ° C. or less
Blended below, and the viscosity at 20 ° C. is 200 to 200
Use for a paint having 0 cps.
~ The resin composition for coating according to any one of 3 to 4. 5. The resin composition for paint according to claim 4, wherein the paint is a paint for woodwork.