JPH06220400A - Coating composition - Google Patents

Abstract

(57) [Summary] [Structure] A coating composition containing a polyfunctional urethane (meth) acrylate represented by the general formula (1). [Chemical 1] [In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents a divalent hydrocarbon group having a total carbon number of 2 to 100, which may contain an ether bond, a carboxylate bond or a phosphate bond, and R ³ represents Diisocyanate residue, X is -Z
A group represented by —CONH—R ³ —NHCO— (wherein Z represents a polymer diol residue and R ³ is the same as above), Y represents a polyhydric alcohol residue, and a represents a number of 3 to 6. , B
Represents a number from 0 to 3] [Effect] This coating composition is excellent in abrasion resistance, adhesion to a substrate, flexibility and stain resistance, and is excellent as a hard coating material.

Description

Detailed Description of the Invention

[0001]

The present invention has excellent curability, good adhesion to various substrates, good stain resistance, toughness, wear resistance, and
The present invention relates to a coating composition which has excellent scratch resistance and is particularly suitable for hard coating of plastic, woodworking, metal, ceramics, glass and the like.

[0002]

2. Description of the Related Art Conventional hard coat materials have been used for the purpose of imparting hardness and aesthetics to the surface of plastic, wood, metal and the like. Among these, thermosetting silicone-based materials and radiation-curable polyfunctional acrylic materials are the mainstream materials. Generally, when high hardness is required, silicone-based materials are used. Functional acrylics are used.

[0003]

The curable resin used as such a hard coat material is usually required to have the following characteristics. (1) Liquid at room temperature and high workability, (2) Fast curing and good productivity, (3) Sufficient hardness,
It has flexibility, (4) it has excellent wear resistance and scratch resistance, (5) it has excellent oil resistance and stain resistance, and (6) it has suitable adhesion to the substrate. To be
(7) Excellent weather resistance, (8) Excellent heat resistance and hydrolysis resistance, and (9) Excellent resistance to chemicals such as acids and alkalis.

In particular, the hard coat material is required to have high hardness and sufficient flexibility, that is, toughness.
In general, when the crosslink density is increased to increase the hardness, the flexibility is lost, which causes the occurrence of cracks and the like, and no material sufficiently satisfies both of them.

An object of the present invention is to provide a coating composition which has high hardness and toughness and is good as a hard coat material.

[0006]

The present invention is intended to solve the above-mentioned problems and is represented by the following general formula (1):

[0007]

[Chemical 2]

[In the formula, R ¹ represents a hydrogen atom or a methyl group, and R ² has a total carbon number of 2 to 2, which may contain an ether bond, a carboxylate bond or a phosphate bond.
100 represents a divalent hydrocarbon group, R ³ represents a diisocyanate residue, X represents a formula (1a) -Z-CONH-R ³ -NHCO- (1a) (wherein Z represents a polymer diol residue). , R ³ is the same as the above), Y is a polyhydric alcohol residue, a is a number of 3 to 6, and b is a number of 0 to 3]. The present invention relates to a coating composition containing urethane (meth) acrylate.

The polyfunctional urethane (meth) acrylate used in the present invention is represented by the above general formula (1), and in the formula (1), the group represented by R ² is linear or branched. A chain or cyclic alkylene group, or 1 to 15 alkyl ether residues in the alkylene group,
Examples thereof include a group to which a fatty acid residue or an alkylphosphoric acid residue is bound. Here, as R ² , an alkylene group having 2 to 3 carbon atoms is particularly preferable. Examples of the group represented by R ³ include a saturated or unsaturated hydrocarbon group having 6 to 30 carbon atoms, which may include a carboxylate residue, a carboxyl group and the like. Examples of the polymer diol residue represented by Z include a polyether diol residue, a polyester diol residue, a polycaprolactone diol residue, a polymethylvalerolactone diol residue, a polycarbonate diol residue, and the like. Ether diol residues are preferred. Further, examples of the polyhydric alcohol residue represented by Y include residues of compounds having 3 to 6 hydroxyl groups, but of compounds having 3 to 4 hydroxyl groups, particularly compounds having 3 hydroxyl groups. Residues are preferred. Further, the number of b is 0 to 3, but 1 or 2 is particularly preferable.

The polyfunctional urethane (meth) acrylate (1) used in the present invention has, for example, a hydroxyl group-containing (meth) acrylate compound (2), a diisocyanate compound (3) and a polyhydric alcohol (4) [as represented by the following formula: Further, if desired, it is produced by reacting a polymer diol compound (5)].

[0011]

[Chemical 3]

Specifically, the isocyanate group of the diisocyanate compound (3) is converted to the hydroxyl group of the polyhydric alcohol (4) (optionally via the hydroxyl group of the polymer diol (5)) and the hydroxyl group-containing (meth) acrylate compound (2). It is produced by reacting with each of the hydroxyl groups of. This reaction is performed by a method of reacting the diisocyanate compound (3) and the hydroxyl group-containing (meth) acrylate compound (2), and then reacting the (polymer diol compound (5)) and the polyhydric alcohol (4).

Examples of the diisocyanate compound (3) used in the present invention include 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate and 1,3.
-Xylylene diisocyanate, 1,4-xylylene diisocyanate, 1,5-naphthalene diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, 3,3'-dimethyl-4,4'-diphenylmethane diisocyanate, 4,4'- Diphenylmethane diisocyanate, 3,3'-dimethylphenylene diisocyanate, 4,4'-biphenylene diisocyanate, 1,6-hexane diisocyanate, isophorone diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, bis (2-isocyanatoethyl) fumarate , 6-isopropyl-1,3-
Phenyl diisocyanate, 4-diphenyl propane diisocyanate, lysine diisocyanate, hydrogenated diphenyl methane diisocyanate, hydrogenated xylylene diisocyanate, tetramethyl xylylene diisocyanate and other polyisocyanate compounds, among others, hydrogenated xylylene diisocyanate, isophorone diisocyanate, Hydrogenated diphenylmethane diisocyanate and the like are preferable. These polyisocyanates can be used alone or in combination of two or more.

Examples of the hydroxyl group-containing (meth) acrylate compound (2) include 2-hydroxyethyl (meth)
Acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate,
2-hydroxy-3-phenyloxypropyl (meth)
Acrylate, 1,4-butanediol mono (meth) acrylate, 2-hydroxyalkyl (meth) acryloyl phosphate, 4-hydroxycyclohexyl (meth) acrylate, 1,6-hexanediol mono (meth) acrylate, neopentyl glycol mono (Meth) acrylate, trimethylolpropane di (meth) acrylate, trimethylolethane di (meth) acrylate, pentaerythritol tri (meth) acrylate, dipentaerythritol penta (meth) acrylate, the following formula (6)

[0015]

[Chemical 4]

[Wherein R ¹ represents a hydrogen atom or a methyl group, and n represents a number of 1 to 15] (meta)
Acrylate etc. are mentioned. Further, compounds obtained by addition reaction of a glycidyl group-containing compound such as alkyl glycidyl ether, allyl glycidyl ether, glycidyl (meth) acrylate and (meth) acrylic acid can also be mentioned. Among these hydroxyl group-containing (meth) acrylate compounds, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate and the like are particularly preferable.

Examples of the polymer diol compound (5) used in the present invention include compounds such as polyether diol, polyester diol, polycaprolactone diol, polymethyl valerolactone diol, and polycarbonate diol, but in terms of curability and toughness. From the viewpoint, a polyether diol compound is desirable.

Specific examples of the aliphatic polyether diol include homo- or copolymerized polyether diols of ethylene oxide, propylene oxide, 1-butene oxide, oxetane, tetrahydrofuran and alkyl-substituted tetrahydrofuran. Examples of the alicyclic polyether diol include alkylene oxide addition diol of hydrogenated bisphenol A and alkylene oxide addition diol of hydrogenated bisphenol F. Examples of commercially available products of these aliphatic or alicyclic polyether polyols include Unisafe DC1100, Unisafe DC1800, Unisafe DCB1100, Unisafe DCB1800 (above, NOF Corporation); PPTG
4000, PPTG2000, PPTG1000, PT
G2000, PTG3000, PTG650, PTGL
2000, PTGL1000 (above, Hodogaya Chemical);
EXENOL4020, EXENOL3020, EXE
NOL2020, EXENOL1020 (above, manufactured by Asahi Glass); PBG3000, PBG2000, PBG100
0, Z3001 (above, manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and the like.

Examples of the aromatic polyether diol compound include alkylene oxide addition diol of bisphenol A, alkylene oxide addition diol of bisphenol F, alkylene oxide addition diol of hydroquinone, and alkylene oxide addition diol of naphthoquinone. These aromatic polyether polyols are commercially available, for example, Uniol DA40.
0, DA700, DA1000, DB400 (above, made by NOF Corporation).

Examples of the polyhydric alcohol (4) used in the present invention include trimethylolpropane and its ethylene oxide / propylene oxide adducts, pentaerythritol, dipentaerythritol, glycerin and alkylene oxide adduct polyols. Examples of commercially available products include TMP30 and PNT4G
lycol, EDA P4, EDA P8 (above, manufactured by Nippon Emulsifier); quadrol (manufactured by Asahi Denka Co., Ltd.) and the like. Of these, ethylene oxide adduct of trimethylolpropane and quadrol are preferable.

In the above reaction, usually copper naphthenate,
Cobalt naphthenate, zinc naphthenate, lauryl di-n
The reaction is carried out using 0.01 to 1 part by weight of a urethane-forming catalyst such as butyltin, triethylamine, DABCO, methyl DABCO, etc., based on 100 parts by weight of the total amount of the reaction product.
The reaction temperature in this reaction is usually 10 to 90 ° C., and preferably 30 to 80 ° C.

The polyfunctional (meth) acrylate (1) thus obtained is incorporated in the coating composition of the present invention preferably in the range of 5 to 99% by weight. Other components in the coating composition include a polymerization initiator and, if necessary, other radiation-curable polymer, reactive diluent and other additives within a range not impairing the properties of the composition of the present invention. Can be added. An organic solvent can also be used as the non-reactive diluent.

Examples of the polymerization initiator include a thermal polymerization initiator and a photopolymerization initiator. When the composition of the present invention is thermally cured, a radical polymerization initiator is usually used as the thermal polymerization initiator. Examples of radical polymerization initiators include:
Examples thereof include peroxides and azo compounds, and specific examples include benzoyl peroxide and t-butyl-
Examples thereof include oxybenzoate and azobisisobutyronitrile.

When the composition of the present invention is photocured,
It is preferable to add a photopolymerization initiator and optionally a photosensitizer to the composition of the present invention. Examples of the photopolymerization initiator used include 1-hydroxycyclohexyl phenyl ketone, 2,2-dimethoxy-2-phenylacetophenone, xanthone, fluorenone, benzaldehyde, fluorene, anthraquinone, triphenylamine, carbazole, 3-methylacetophenone, Four
-Chlorobenzophenone, 4,4'-dimethoxybenzophenone, 4,4'-diaminobenzophenone, Michler's ketone, benzoin propyl ether, benzoin ethyl ether, benzyl dimethyl ketal, 1- (4-
Isopropylphenyl) -2-hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1
-Phenylpropan-1-one, thioxanthone, diethylthioxanthone, 2-isopropylthioxanthone, 2-chlorothioxanthone, 2-methyl-1- [4
-(Methylthio) phenyl] -2-morpholino-propan-1-one, 2,4,6-trimethylbenzoyldiphenylphosphine oxide and the like can be mentioned. Commercially available products are IRUGACURE 184, 6 manufactured by Ciba-Geigy.
51, 500, 907, CGI369, CG24-6
1; BASF's Lucirine LR8728; Merck's Darocure 1116, 1173; UCB's Ubecryl P36; Akzo's VICURE 55 and the like. As the photosensitizer, triethylamine, diethylamine, N-methyldiethanolamine,
Ethanolamine, 4-dimethylaminobenzoic acid, 4-
Examples thereof include methyl dimethylaminobenzoate, ethyl 4-dimethylaminobenzoate, and isoamyl 4-dimethylaminobenzoate. Examples of commercially available products include Ubecryl P102, 103, 104 and 105 manufactured by UCB.

These polymerization initiators and photosensitizers may be used alone or in combination of two or more, and the polymerization initiator is added to the composition of the present invention in the range of 0.1 to 10% by weight. When the composition of the present invention is cured by using heat and ultraviolet rays in combination, the above radical polymerization initiator can be used in combination.

Other radiation-curable polymers that can be added to the composition of the present invention include urethane (meth) acrylates other than the above urethane (meth) acrylate polymers, polyester (meth) acrylates, and epoxy (meth) acrylates. , Polyamide (meth) acrylate, siloxane polymer having a (meth) acryloyloxy group, and the like. These can be added alone or in combination of two or more.

Examples of the reactive diluent include monofunctional compounds and polyfunctional compounds. As the monofunctional compound, 2-hydroxyethyl (meth) acrylate, 2-
Hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, butyl (meth) acrylate, amyl (meth) Acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, pentyl (meth) acrylate, isoamyl (meth) acrylate, hexyl (meth) acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, isooctyl (meth) Acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, isodecyl (meth) acrylate, undecyl (meth) acrylate Dodecyl (meth) acrylate, lauryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, butoxyethyl (meth)
Acrylate, ethoxydiethylene glycol (meth)
Acrylate, benzyl (meth) acrylate, cyclohexyl (meth) acrylate, phenoxyethyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, methoxyethylene glycol (meth) acrylate, ethoxyethoxyethyl (meth ) Acrylate, methoxy polyethylene glycol (meth)
Acrylate, methoxy polypropylene glycol (meth) acrylate, dicyclopentadiene (meth) acrylate, dicyclopentanyl (meth) acrylate,
Dicyclopentenyl (meth) acrylate, tricyclodecanyl (meth) acrylate, isobornyl (meth)
Acrylate, bornyl (meth) acrylate, diacetone (meth) acrylamide, isobutoxymethyl (meth) acrylamide, N-vinylpyrrolidone, N-vinylcaprolactam, N, N-dimethyl (meth) acrylamide, t-octyl (meth) acrylamide, Dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, 7-amino-3,7-dimethyloctyl (meth) acrylate, N, N-diethyl (meth) acrylamide, N, N'-dimethylaminopropyl (meth ) Acrylamide, (meth) acryloylmorpholine, hydroxybutyl vinyl ether, lauryl vinyl ether, cetyl vinyl ether, 2-ethylhexyl vinyl ether and the following formulas (7)-
The compound represented by (9) can be mentioned.

[0028]

[Chemical 5]

[Wherein, R ¹ represents a hydrogen atom or a methyl group, R ⁴ represents an alkylene group having 2 to 6 carbon atoms, preferably 2 to 4 carbon atoms, R ⁵ represents a hydrogen atom or 1 to 12 carbon atoms,
Preferably, it represents an alkyl group of 1 to 9, m is 0 to 12,
Preferably, the number is 1 to 8]

[0030]

[Chemical 6]

[Wherein R ¹ is as described above and R ^{6 is}
Represents an alkylene group having 2 to 8 carbon atoms, preferably 2 to 5, and p represents a number of 1 to 8, preferably 1 to 4]

[0032]

[Chemical 7]

[Wherein R ¹ , R ⁶ and p are as described above and R ^{7 to} R ¹¹ each represent a hydrogen atom or a methyl group] As commercial products, Aronix M111, M
113, M114, M117 (above, manufactured by Toagosei Kagaku); KAYARAD TC110S, R629, R6
44 (above, manufactured by Nippon Kayaku); Viscoat 3700 (manufactured by Osaka Organic Chemical).

As the polyfunctional compound, trimethylolpropane tri (meth) acrylate, pentaerythritol tri (meth) acrylate, ethylene glycol di (meth) acrylate, triethylene glycol divinyl ether, tetraethylene glycol di (meth) acrylate, Polyethylene glycol di (meth) acrylate, tripropylene glycol diacrylate, 1,
4-butanediol di (meth) acrylate, 1,6-
Hexanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, trimethylolpropane trioxyethyl (meth) acrylate, tris (2-hydroxyethyl) isocyanurate tri (meth) acrylate, tris (2-hydroxyethyl) Examples thereof include isocyanurate di (meth) acrylate, tricyclodecane dimethanol di (meth) acrylate, and epoxy (meth) acrylate obtained by adding (meth) acrylate to diglycidyl ether of bisphenol A. Commercial products include Copimer UV, SA1002, S
A2007 (above, manufactured by Mitsubishi Yuka); Viscoat 700
(Made by Osaka Organic Chemistry); KAYARAD R-604, D
PCA-20, -30, -60, -120, HX-62
0, D-310, D-330 (all manufactured by Nippon Kayaku); Aronix M-210, M-215, M-315, M-
325 (above, manufactured by Toagosei Kagaku) and the like.

Organic solvents that can be used as the non-reactive diluent include toluene, xylene, ethyl acetate,
Butyl acetate, acetone, methyl ethyl ketone, methyl cellosolve and the like can be mentioned.

The composition of the present invention is cured by heat and / or radiation. Here, the radiation refers to radiation such as infrared rays, visible rays, ultraviolet rays and X-rays, electron rays, α rays, β rays, and γ rays.

In the composition of the present invention, other additives such as epoxy resin, polyamide, polyamideimide, polyurethane, polybutadiene, chloroprene, polyether, polyester, pentadiene derivative, SB
S (styrene / butadiene / styrene block copolymer) and hydrogenated SEBS (styrene / ethylene / butylene / styrene), SIS (styrene / isoprene /
Polymers such as styrene block copolymer), petroleum resin, xylene resin, ketone resin, fluorine-based oligomer,
Silicone-based oligomers, polysulfide-based oligomers, etc. can also be blended.

Further, various additives other than the above, for example, antioxidants, colorants, ultraviolet absorbers, light stabilizers, silane coupling agents, thermal polymerization inhibitors, leveling agents, surfactants, storage stabilizers, plasticizers. If desired, a lubricant, a solvent, a filler, an antiaging agent, a wettability improver, a coating surface improver and the like can be added. For example, as the antioxidant, I
rganox 1010, 1035, 1076, 1222
(Above, manufactured by Ciba-Geigy) and the like. Examples of the ultraviolet absorber include Tinuvin P, 234, 320 and 32.
6, 327, 328, 213, 329 (above, manufactured by Ciba Geigy); SEESORB 102, 103, 501, 2
No. 02, 712 (above, manufactured by Cypro Kasei) and the like, and the light stabilizer is Tinuvin 292, 144, 6
22LD (above, Ciba Geigy); Sanor LS77
0, LS440 (manufactured by Sankyo); Sumisorb TM-
061 (manufactured by Sumitomo Chemical Co., Ltd.) and the like, and as the silane coupling agent, γ-aminopropyltriethoxysilane, γ-mercaptopropyltrimethoxysilane, γ-
Examples of commercial products of methacryloxypropyltrimethoxysilane include SH6062, 6030 (made by Toray Silicone); KBE903, 603, 403 (made by Shin-Etsu Chemical).

The viscosity of the composition of the present invention is usually 10 to 20.
000 cp / 25 ° C, preferably 20-10,000 cp / 2
It is 5 ° C.

[0040]

EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited to these examples. In the following, parts mean parts by weight.

Synthesis Example 1 In a reaction vessel equipped with a stirrer, 217.5 g of isophorone diisocyanate and 0.65 of dibutyltin dilaurate.
g, 0.2 g of 2,6-di-t-butyl-4-methylphenol as a polymerization inhibitor, and 200 g of tripropylene glycol diacrylate as a reaction diluent.
This was cooled to 10 ° C. in an ice-water bath, and then 56.9 g of hydroxyethyl acrylate was added thereto while controlling the temperature at 20 ° C. or lower. 10-20 ° C after addition
After continuing the stirring for 1 hour, 490 g of polypropylene glycol (EXENOL 1020 manufactured by Asahi Glass Co., Ltd.) was added while keeping the temperature at 50 ° C or lower, and the stirring was continued at 50 to 60 ° C for 3 hours. Then, 36 g of quadrol was added and the mixture was further stirred for 5 hours and then the reaction was terminated to obtain a urethane acrylate [A-1] having a number average molecular weight of 6530.

Synthesis Example 2 Pentaerythritol 38.3 instead of quadrol
Synthesis was performed in the same manner as in Synthesis Example 1 using g to obtain a urethane acrylate [A-2] having a number average molecular weight of 6380.

Synthesis Example 3 A reaction vessel equipped with a stirrer was charged with 327 g of hydrogenated xylylene diisocyanate and 0.2 g of 2,6-di-t-butyl-4-methylphenol as a polymerization inhibitor. This one
After cooling to 0 ° C. in an ice-water bath, 249 g of hydroxyethyl acrylate was added thereto while controlling the temperature at 20 ° C. or lower. After the addition, the mixture was further stirred at 10 to 20 ° C. for 1 hour, and then polytetramethylene glycol having a number average molecular weight of 1000 (PTMG1000 manufactured by Hodogaya Chemical Co., Ltd.) 1
44 g was added keeping the temperature below 50 ° C. Then, stirring was continued at 50 to 60 ° C. for 3 hours. After that, 82 g of trimethylolpropane ethylene oxide-added triol was added, and the mixture was further stirred for 5 hours and then the reaction was terminated to obtain a urethane acrylate [A-3] having a number average molecular weight of 4580.

Example 1 A reaction vessel equipped with a stirrer was charged with urethane acrylate [A
-1] 37.5 parts, viscoat 190 28.0 parts,
28 parts of tripropylene glycol diacrylate, 3.0 parts of benzophenone, 3.0 parts of Irgacure 184, 0.5 parts of VICURE55, 50-60 ° C
The mixture was stirred and mixed in to obtain a transparent liquid composition having a viscosity of 2500 cp / 25 ° C.

Example 2 A composition was prepared in the same manner as in Example 1 except that urethane acrylate [A-1] was replaced with [A-2]. The viscosity of the composition was 3100 cp / 25 ° C.

Example 3 A composition was prepared in the same manner as in Example 1 except that urethane acrylate [A-1] was replaced with [A-3]. The viscosity of the composition was 1000 cp / 25 ° C.

Test Example 1 Using the liquid composition obtained as described above, test pieces were prepared in the following manner and their performances were evaluated. (1) Preparation of test piece Using a RDS18 bar coater (manufactured by Yasuda Seiki Co., Ltd.), a liquid material is applied on a transparent soft vinyl chloride plate test piece and irradiated with 1.0 J / cm ² of ultraviolet light to cure it. A film was obtained. Next, the test piece is placed at 23 ° C. and relative humidity of 50.
% For 24 hours to prepare a test piece. (2) Abrasion resistance Based on JIS K5400, the degree of abrasion of the coating film by the abrasion wheel was examined using a Taber type abrasion tester, and the abrasion loss was expressed. Worn wheel; CS-10F, load: 500 g × 2, rotation speed: 100 rotations. (3) Adhesion According to JIS K5400, the adhesion with the substrate was measured by the cross-cut tape method. (4) Flexibility The appearance of the coating film surface when the test piece was bent 180 degrees and returned to the original state was visually observed. (5) Contamination resistance Based on JIS K5400, the contamination resistance of the magic pen contamination was visually observed.

As a result, as shown in Table 1, the coating composition of the present invention had sufficiently satisfactory performances in all items of abrasion resistance, adhesion, flexibility and stain resistance.

[0049]

[Table 1]

[0050]

The coating composition of the present invention is excellent in abrasion resistance, adhesion to a substrate, flexibility and stain resistance, and is suitable as a hard coating material.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Dai ▲ High ▼ Toru 2-11-24 Tsukiji, Chuo-ku, Tokyo Within Nippon Synthetic Rubber Co., Ltd. (72) Inventor Takashi Ukaji 2-chome Tsukiji, Chuo-ku, Tokyo 11-24 No. 24 within Nippon Synthetic Rubber Co., Ltd.

Claims (1)

[Claims] 1. The following general formula (1): [In the formula, R ¹ represents a hydrogen atom or a methyl group, R ² represents a divalent hydrocarbon group having a total carbon number of 2 to 100, which may contain an ether bond, a carboxylate bond or a phosphate bond, and R 2 ³ represents a diisocyanate residue, X represents a group represented by the formula (1a) -Z-CONH-R ³ -NHCO- (1a) (wherein Z represents a polymer diol residue, and R ³ is the same as above). Where Y represents a polyhydric alcohol residue, a represents a number of 3 to 6, and b represents a number of 0 to 3]. A coating composition containing a polyfunctional urethane (meth) acrylate.