JPH0413708A - coating composition - Google Patents

Abstract

PURPOSE:To obtain the title composition suitable for skiing tool, etc., having excellent curing properties, surface hardness, appearance, coating workability, comprising a specific polyurethane (meth) acrylate, a (meth) acrylate group- containing polymerizable compound, a photopolymerization initiator and a fiber-based polymer in a specific ratio. CONSTITUTION:The objective composition comprising (A) 20-60 pts.wt. polyurethane (meth)acrylate prepared by reacting a polyisocyanate (e.g. isophorone diisocyanate) containing at least two isocyanate groups with a polyol and a hydroxyl group-containing (meth)acrylic compound, (B) 80-40 pts.wt. (meth) acrylate group-containing polymerizable compound [e.g. methyl (meth)acrylate], (C) 0.1-10 pts.wt., preferably 1-5 pts. wt. photopolymerization initiator (e.g. 2,2- dimethoxy-2-phenylacetophenone) and (D) 5-20 pts. wt. fiber-based polymer (preferably cellulose acetate butylate).

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention provides an ultraviolet curable coating suitable for ski equipment, etc., which has excellent curability, surface hardness, and appearance, and is also excellent in workability during painting. Regarding materials.

(Prior Art) Conventionally, various base materials have been used for ski equipment, such as ski boards, poles, etc. due to the diversity of their designs, and therefore acrylic polyol-based materials have been mainly used as coating materials for skis.

However, acrylic polyol coating materials are
Since it is a liquid curing type, there are restrictions on pot life and pot life, so a coating material that can be used as a liquid has been desired. In addition, in particular, these tools are required to have a high surface hardness in order to protect the top coat layer from scratches caused when the cover is taken in and out, and scratches caused by ski edges while sliding. Furthermore, since the painting method is usually curtain flow coating method,
Acrylic polyol systems require the use of large amounts of solvent.

From the above points of view, attempts have already been made to use UV-curable coating materials as coating materials for ski equipment, particularly as top coat layers.

(Problems to be Solved by the Invention) Generally, UV-curable coating materials are solvent-free and have high surface hardness, making them suitable coating materials for the above-mentioned applications. Since oligomers having a low molecular weight are mainly blended, the resulting cured coating film has poor surface smoothness and poor appearance. Furthermore, if oligomers with low molecular weights are used extensively, the surface hardness will inevitably be low, making them unsuitable as top coat layers for ski equipment as described above.

Therefore, as a coating material for such products, there has been a strong desire to develop an ultraviolet curable coating material that is substantially solvent-free, has good coating workability, and has excellent surface hardness and appearance of the cured coating film.

(Means for Solving the Problems) As a result of intensive studies in view of the above-mentioned problems, the present inventors added cellulose-based polymer to a composition mainly composed of a specific urethane poly(meth)acrylate. The inventors discovered that it is possible to achieve the original objective by blending the two, leading to the completion of the present invention.

That is, the structure of the present invention is as follows: (A) 20 to 60% by weight of polyurethane (meth)acrylate obtained by reacting a polyisocyanate having at least two isocyanate groups, a polyol, and a (meth)acrylic compound having a hydroxyl group; (B) 80 to 40 parts by weight of a polymerizable compound having at least one (meth)acrylate group, (C) 0.1 to 10 parts by weight of a photopolymerization initiator, (D) 5 to 40 parts by weight of a cellulose polymer It is a composition containing 20 parts by weight, and further additives such as a leveling agent, an antifoaming agent, an inhibitor, etc. can be added as component (E) in an amount of 0.01 to 5 parts by weight as necessary. be.

Specific examples of polyurethane (meth)acrylate polyisocyanates obtained by reacting component (A), a polyisocyanate having at least two inocyanate groups, a polyol, and a (meth)acrylic compound having a hydroxyl group, include: Tolylene diisocyanate, ethylene diisocyanate, 1,2-diisocyanatopropane, 1,3-diisocyanatopropane, 4,4'-diphenylmethane diisocyanate, xylylene diisocyanate, tetramethylxylylene diisocyanate, hexamethylene diisocyanate, lysine isocyanate, 4,4'-methylenebis(cyclohexyl)isocyanate, methylcyclohexane 2,4-diisocyanate, methylcyclohexane 2,6-diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, isophorone diisocyanate, trimethylhexamethylene diisocyanate,
Examples include diisocyanates such as tetramethylene diisocyanate, dimer acid diisocyanate, 2-isocyanatoethyl, and 2,6-dicyanatohexanoate, triisocyanate single biuret, polymers thereof, and adducts thereof with polyols. . If the product is to be used outdoors, take non-yellowing type isophorone diisocyanate, 4,4'-
Diisocyanatocyclohexylmethane and tetramethylxylylene diisocyanate are preferred.

Specific examples of the polyol component include, but are not limited to,
Ethylene glycol, propylene glycol, butylene glycol, polyethylene glycol, polypropylene glycol, polybutylene glycol, polytetramethylene glycol, trimethylolpropane, polytrimethylolpropane, pentaerythrol, polypentaerythrol, sorbitol, mannitol, glycerin, polyglycerin Examples include alcohols and polyether polyols such as, polyester polyols synthesized from polyhydric alcohols and polybasic acids, and polyester polyols such as polycaprolactone polyols.

The reaction between the polyisocyanate and the monohydroxy polyallyl ether compound is completed by heating at 60 to 70°C for several hours using a tin-based catalyst such as dibutyltin dilaurate so that the isocyanate and hydroxyl groups are approximately equal. do.

Among them, tetramethylxylylene diisocyanate, isophorone diisocyanate, dicyclomethane-4,4'-
Urenane acrylate consisting of methane diisocyanate is preferred from the viewpoint of yellowing.

In addition, examples of the compound having at least one (meth)acrylate group as component (B) include methyl (meth)acrylate, ethyl (meth)acrylate, and (meth)acrylate group.
Propyl acrylate, n-butyl (meth)acrylate,
(meth)acrylic acid t-butyl, (meth)acrylic acid 2
-ethylhexyl, n-nonyl (meth)acrylate, (
Cyclohexyl (meth)acrylate, benzyl (meth)acrylate, dicyclopentenyl (meth)acrylate, (
2-dicyclopentenoxyethyl meth)acrylate, (
methoxyethyl acrylate, ethoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate,
(meth)methoxyethoxyethyl acrylate, (meth)
Ethoxyethoxyethyl acrylate, tetrahydrofurfuryl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-human-xybutyl (meth)acrylate, (
(meth)acrylic acid monomers such as meth)acrylic acid and (meth)acryloylmorpholine, N-vinyl-2-pyrrolidone, N-vinylimidazole, N-vinylcaprolactam, styrene, a-methylstyrene, vinyltoluene, allyl acetate, Monofunctional acrylates such as vinyl acetate, vinyl propionate, vinyl benzoate, vinyl compounds, trimethylolpropane tri(meth)acrylate,
Pentaerythritol tetra(meth)acrylate, triallyl cyanurate, triallyl isocyanurate,
Ethylene oxide or propylene oxide 2 of trimethylolpropane, such as triallyl formal (1,3,5-triacryloylhexahydro-8-triazine), polypropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, etc.
Tri(meth)acrylate with ~6 mole addition, pentaerythritol to ethylene oxide or tetra(meth)acrylate with 2 to 6 mole addition of propylene oxide, ditrimethylolpropane tetraacrylate, hydroxypivalic acid neopentyl glycol diacrylate, dipentaerythritol Examples include hexaacrylate, pentaerythritol tri(meth)acrylate, neopentyl glycol di(meth)acrylate, and diacrylate of dicyclopentagenyl diol.

In consideration of skin irritation and suitability for curtain flow coaters, bifunctional acrylates are preferred.

The blending ratio of the above (A) component and (B) component is (A) component 2
0 to 60 parts by weight and 80 to 40 parts by weight of component (B) are preferred. If the amount is less than this, the coating film tends to lose its elongation, and if it is more than this amount, the viscosity becomes too high and suitability for curtain flow coater is not obtained. It tends to disappear.

Specific examples of the photopolymerization initiator (C) used in the present invention include 2-2 dimethoxy-2-phenylacetophenone, acetophenone, benzophenone, xanthofluorenone, benzaldehyde, anthraquinone, 3-
Methylacetophenone, 4-chlorobenzophenone, 4
．． 4'-Diaminobenzophenone, benzoinpropyl ether, benzoin ethyl ether, benzyl dimethyl ketal, 1-(4-isopropylphenyl)-2-
Hydroxy-2-methylpropan-1-one, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 4-oxanthone, camphorquinone, 2-methyl-
1-[4(methylthio)phenyl]-2-morpholino-
Examples include propan-1-one. Furthermore, a photopolymerization initiator having at least one acryloyl group or methacryloyl group in the molecule can also be used. These photopolymerization initiators can be used alone or in a mixture of two or more. The amount used is usually 0.1 to 10 parts by weight, preferably 1 to 5 parts by weight.

The light used here is ultraviolet light belonging to the wavelength range 250-4501.

The cellulose polymer which is component (D) of the present invention includes nitrocellulose, acetyl cellulose, acetate/butyrate, methyl and ethyl cellulose, carboxymethyl cellulose, etc. ,
From the viewpoint of water resistance and water resistance, acetate/butyrate systems are preferred, among which cellulose acetate/butyrate,
Cellosolve acetate propionate is preferred. The blending ratio is preferably 5 to 20 parts by weight,
If the amount is less than 5 parts by weight, the appearance will not be improved, and if it is more than 20 parts by weight, the adhesion to the substrate will be poor.

Further, the resin composition of the present invention may contain an organic solvent in order to adjust the viscosity to a desired value depending on the case. Examples of organic solvents include ketone compounds such as acetone, methyl ethyl ketone, and cyclohexanone; ester compounds such as methyl acetate, ethyl acetate, butyl acetate, ethyl lactate, and methoxyethyl acetate; ether compounds such as diethyl ether, ethylene glycol dimethyl ether, and dioxane. ; Aromatic compounds such as toluene and xylene; Aliphatic compounds such as pentane and hexane; and halogenated hydrocarbons such as methylene chloride, chlorobenzene and chloroform.

Furthermore, additives such as antifoaming agents, lubricants, abrasives, rust preventives, and antistatic agents may be added to the resin composition of the present invention.

(Example) The present invention will be explained in more detail below with reference to Examples.

Synthesis Examples 1 to 6: Polyisocyanate component, polyol, in the amounts shown in Table 1
Total amount of (meth)acrylic compound having a hydroxyl group and 2-ethylhexyl acrylate (2-EHA) 100
Prepare dibutyltin dilaurate in an amount of 0.02 parts per part, add dropwise the polyol component in the amount shown in Table 1 while keeping it at 40 ° C. After reacting for a sufficient time, add 0.1 part of hydroquinone, Further, heating and stirring at 75°C for a sufficient period of time was continued, and the urethane acrylate UA-1-UA
-6 was obtained.

Examples 1 to 12; Comparative Examples 1 to 4: Using the urethane acrylates of Synthesis Examples 1 to 6 above, the formulations shown in (Table 2)-1 and (Table 2)-2 were made to produce various coating materials for skis. Examples 1 to 11 and Comparative Examples 1 to
I got 4. Apply these paints to the ABS board laminated skis with a film thickness of 80μ using a curtain flow coater made by Iwata Painting Machine.
After applying the coating to a thickness of 100 μm, the UV irradiation device U V-5003 manufactured by Mitsubishi Rayon Engineering was used at 80 w/cx + lamp body, and the conveyor speed was 9 s/sin.
UV irradiation was performed under the following conditions. Lay out the obtained skis (
Evaluations were performed as shown in Tables 2)-1 and 2)-2.

(Effects of the Invention) As is clear from Table 2, the composition of the present invention has a coating viscosity suitable for curtain flow coaters, has sufficient hardness, and has excellent adhesion, appearance, and yellowing. It turns out that it is excellent. On the other hand, in Comparative Example 1, which does not contain polyurethane (meth)acrylate as component (A), the coating has a high viscosity and lacks suitability for the curtain 70, and furthermore, it not only has low adhesion but also tends to yellow. In addition, Comparative Example 2, which does not contain any textile polymer as component (D), has a poor appearance, and Comparative Example 3, in which the blend with polyurethane (meth)acrylate as component (^) deviates from the specifications of the present invention. , 4, if the upper limit of parts by weight is exceeded, the viscosity of the paint becomes too high, and if the lower limit is exceeded, the viscosity is low and the adhesion is poor, and in both cases, curtain flow suitability is lacking.
There is also a problem in terms of hardness.

(Table-2)-1 Examples (Table-2) Paint viscosity: 2 BM type Curtain flow suitability: Iwata Painter Curtain Flow Coater used Pencil hardness: 2 Mitsubishi Uni (product name) Adhesiveness: Outside of goban-me Ceronow tape Visual judgment Yellowing: Judgment by fade meter 1 (X) R△E (Note 1) ANDA: Hydroxypivalic acid neopentyl glycol ester diac I route (Note 2) TPGDA Nitripropylene glycol diacrylate (Note 3) ) Dianal AD9002: Paint additive manufactured by Mitsubishi Rayon Co., Ltd. (Unit: parts by weight)

Claims (1)

[Claims] (1) (A) 20 to 60 parts by weight of polyurethane (meth)acrylate obtained by reacting a polyisocyanate having at least two isocyanate groups, a polyol, and a (meth)acrylic compound having a hydroxyl group; (B) 80 to 40 parts by weight of a polymerizable compound having at least one (meth)acrylate group, (C) 0.1 to 10 parts by weight of a photopolymerization initiator, and (D) 5 to 20 parts by weight of a cellulose polymer. A coating composition comprising: