JP3293907B2 - Radiation-curable resin composition and cured product thereof - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a radiation-curable resin composition. More specifically, the present invention relates to a radiation-curable resin composition containing a specific urethane (meth) acrylate having a carboxyl group in a molecule as a component.

[0002]

2. Description of the Related Art Radiation-curable resin compositions which can be cured by ultraviolet rays or electron beams have been widely used in inks, paints, adhesives, and other applications from pollution-free and energy-saving purposes. Organic solvents are used for washing printers and coating machines after using these inks, paints, etc., but with the recent rise in environmental issues, the demand for changing the washing liquid to aqueous solvents has increased. ing. Nevertheless, in reality, satisfactory water-soluble radiation-curable resin compositions have not yet been obtained.

[0003]

SUMMARY OF THE INVENTION Development with a resin composition which solves the problems in the prior art as described above, that is, a dilute aqueous alkali solution (for example, an aqueous solution of caustic soda, potassium hydroxide, sodium carbonate, ammonia, amines, etc.) can be carried out. It is possible to provide a radiation-curable resin composition in which the uncured portion is easily dissolved in water and easily removed, and the cured portion is excellent in water resistance, solvent resistance, chemical resistance and the like.

[0004]

The present inventors have conducted intensive studies on the problems to be solved by the invention as described above, and as a result, have found that a specific compound having a carboxyl group and a (meth) acryloyl group in the molecule has been identified. By using, it is compatible, has excellent storage stability, can be dissolved and removed with a dilute aqueous alkali solution, and the cured product is found to be a resin composition having excellent water resistance, solvent resistance, chemical resistance, and the like. The present invention has been completed. That is, the present invention relates to a polyol compound (a) and a compound (b) represented by the formula (1).

[0005]

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(Where a and b are each a number from 0 to 10, and the average value of a + b is 0.5 to 20), an organic polyisocyanate (b), and a hydroxyl group-containing (meth) acrylate (c). A radiation-curable resin composition characterized by containing a urethane (meth) acrylate (A) which is a reaction product with (A), a reactive diluent (B), and a photopolymerization initiator (C) as an optional component.

In the present invention, urethane (meth) is a reaction product of a polyol compound (a), a compound (b) represented by the formula (1), an organic polyisocyanate (c), and a hydroxyl group-containing (meth) acrylate (d). Use acrylate (A).

Specific examples of the polyol compound (a) which is a raw material of the urethane (meth) acrylate (A) include:
For example, ethylene glycol, neopentyl glycol, 1,6-hexanediol, 3-methyl-1,5-
Polyols such as pentanediol, polyethylene glycol, trimethylolpropane, polytetramethylene glycol, and the polyols and lactones (for example,
lactone-modified polyols which are reactants of ε-caprolactone, δ-valerolactone, etc., the polyols and polybasic acids (for example, maleic anhydride, succinic anhydride,
Phthalic acid, tetrahydrophthalic anhydride, adipic acid, etc.)
And polyester polyols, polycarbonate polyols, etc., which are the reactants of the above.

The compound (b) represented by the formula (1) is
It can be obtained by reacting dimethylolpropionic acid with ε-caprolactone. In this reaction, 0.25 to 10 mol of ε-caprolactone is reacted per equivalent of hydroxyl group of dimethylolpropionic acid. In order to accelerate the reaction, it is preferable to use stannous chloride, tetrapropyl titanate or the like as a catalyst. The amount of the catalyst used is preferably 50 to 5000 ppm based on the reaction mixture. The reaction temperature is preferably from 70 to 200 ° C, particularly preferably from 80 to 150 ° C. The reaction time is preferably 1 to 20 hours.

Further, specific examples of the organic polyisocyanate (c) include, for example, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, dicyclohexylmethane-diisocyanate , Isophorone diisocyanate, hexamethylene diisocyanate and the like. Specific examples of the hydroxyl group-containing (meth) acrylate (d) include 2-hydroxyethyl (meth) acrylate and 2-hydroxyethyl (meth) acrylate.
Hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, pentaerythritol tri (meth) acrylate, glycerin di (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di ( (Meth) acrylate, N-methylol (meth) acrylamide, and the like.

The reaction between the polyol compound (a), the compound (b) represented by the formula (1), and the organic polyisocyanate (c) is represented by the polyol compound (a) and the formula (1). The organic polyisocyanate (c) preferably has 1.1 to 2.0 equivalents of isocyanate groups per 1 equivalent of hydroxyl groups of the mixture of the compound (b). The usage ratio of the polyol compound (a) and the compound (b) represented by the formula (1) is as follows: the polyol compound (a): the compound (b) represented by the formula (1) is 99 to 40 mol%: 1 to 60 mol% is preferred. The reaction temperature is preferably from 60 to 100 ° C, particularly preferably from 75 to 85 ° C. The reaction time is preferably 5 to 20 hours. Next, the hydroxyl group-containing (meth) acrylate is used per 1 equivalent of an isocyanate group of a reaction product of the polyol compound (a), the compound (b) represented by the formula (1), and the organic polyisocyanate (c). The urethane (meth) acrylate (A) can be obtained by reacting the hydroxyl group of (d), preferably 0.95 to 1.2 equivalents. To prevent this polymerization, polymerization inhibitors such as methylhydroquinone, p-methoxyphenol,
It is preferable to use hydroquinone or the like. The amount of the polymerization inhibitor used is 0.01 to 0.5% by weight based on the reaction mixture.
Is preferred. The reaction temperature is preferably from 60 to 100 ° C, particularly preferably from 75 to 85 ° C. Reaction time is 5-20
Time is preferred.

Next, specific examples of the reactive diluent (B) used in the present invention are widely used from monofunctional ones to polyfunctional ones. , 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, N-vinylpyrrolidone, acryloylmorpholine, carbitol (meth) acrylate, polyethylene glycol di (meth) acrylate, glycerin di (meth) acrylate, glycerin Mono (meth) acrylate, pentaerythritol tri (meth) acrylate,
Water-soluble compounds such as tris (2-hydroxyethyl) isocyanurate di (meth) acrylate can be used.

Further, specific examples of the photopolymerization initiator (C) which can be used as an optional component include 1-hydroxycyclohexylphenyl ketone, benzophenone, 2-methyl-1- [4- (methylthio) phenyl] -2- Morpholino-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -1-butanone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, acetophenone dimethyl ketal, 4, 4'-bisdiethylaminobenzophenone,
4- (2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl ketone) and the like can be mentioned. These can be used alone or in combination of two or more.

Such photopolymerization initiators include ethyl N, N-dimethylaminobenzoate, isoamyl N, N-dimethylaminobenzoate, triethanolamine,
Known or common photopolymerization accelerators such as triethylamine can be used alone or in combination of two or more.

The radiation-curable resin composition of the present invention can be obtained by preparing components (A) to (C) by mixing, dissolving, dispersing, kneading and the like.

The proportion of each component used in the present invention is preferably 29 to 95% by weight, more preferably 39 to 95% by weight for the component (A).
The content of the component (B) is preferably from 5 to 70% by weight, particularly preferably from 20 to 60% by weight.
The components are preferably 0 to 15% by weight, particularly preferably 0 to 15% by weight.
10% by weight.

The radiation-curable resin composition of the present invention may further contain, as necessary, a range not deviating from the object of the present invention, particularly, solubility in dilute alkaline aqueous solution, storage stability, water resistance of the cured product, solvent resistance, Within the range that can maintain chemical resistance, etc.
Known and commonly used organic solvents, inorganic fillers, additives, and others can be added.

The radiation referred to in the present invention is an electron beam, an α ray,
It is a general term for ionizing radiation, light, etc., such as β-rays, γ-rays, X-rays, neutron rays or ultraviolet rays. The radiation-curable resin composition of the present invention can be usually cured by radiating the above-mentioned radiation as it is. The resin composition of the present invention includes, for example, paints, adhesives, printing inks, plate-making materials,
It can be used for coating, photoresist and the like.

[0019]

Next, the present invention will be further described with reference to examples. In the following, all parts are by weight unless otherwise specified. Synthesis Example of Urethane (meth) acrylate Synthesis Example 1 134 parts of dimethylolpropionic acid, 166 parts of ε-caprolactone, stannous chloride, and 0.09 part were charged, and 11
The mixture was heated to 0 ° C. and reacted for about 10 hours. Since the amount of unreacted ε-caprolactone became 1% by weight or less, it was cooled to 60 ° C., and then polytetramethylene glycol (molecular weight: 65
0) 200 parts, isophorone diisocyanate 436.8
Parts, and reacted at 80 ° C. for about 10 hours. Then, 159.5 parts of 2-hydroxyethyl acrylate and 0.6 part of p-methoxyphenol were charged and reacted at 80 ° C. for about 15 hours to obtain urethane acrylate (A-1). ) Got.

Synthesis Example 2 110 parts of dimethylolpropionic acid, 366 parts of ε-caprolactone, and 0.15 part of stannous chloride were charged.
C. and reacted for about 10 hours. The amount of unreacted .epsilon.-caprolactone was reduced to 1% by weight or less. After cooling to 60.degree. C., 10 parts of neopentyl glycol and 287 parts of tolylene diisocyanate were charged. C. for about 10 hours and then 2-hydroxyethyl acrylate 1
34 parts and 0.5 part of p-methoxyphenol were charged, and 8
After reacting at 0 ° C. for about 15 hours, urethane acrylate (A-
2) was obtained.

Examples 1 to 4 The components were dissolved and mixed in accordance with the composition shown in Table 1 (the numerical values indicate parts by weight) to obtain the radiation-curable resin composition of the present invention.
Using a radiation bar this radiation-curable resin composition,
Each was applied to tin-free steel so as to have a thickness of 20 μm, and was irradiated with ultraviolet rays from a high-pressure mercury lamp and cured to obtain a test piece. Water resistance, solvent resistance,
The alkali resistance and the solubility of the composition in dilute alkali and aqueous solution were tested.

[0022]

Table 1 Example * 6 1 2 3 4 Urethane acrylate (A-1) obtained in Synthesis Example 1 70 30 Urethane acrylate (A-2) obtained in Synthesis Example 2 40 60 30 2-hydroxyethyl acrylate 20 10 10 Acryloylmorpholine 30 30 30 Polyethylene glycol diacrylate 10 30 Irgacure 184 * 1 5 5-5 Solubility in dilute alkaline aqueous solution * 2 ○ ○ ○ ○ Cured coating water resistance * 3 ◎ ◎ ◎ ◎ Solvent resistance * 4 ◎ ◎ ◎ ◎ Alkali resistance * 5 ◎ ◎ ○ ○

Note * 1 Irgacure 184: Photopolymerization initiator, 1-hydroxy-cyclohexyl-phenylketone, manufactured by Ciba-Geigy * 2 Solubility in dilute alkaline aqueous solution: 20 μm each in tin-free steel using a wire bar And apply it to a 1.5% aqueous solution of sodium carbonate.
After soaking for 0 minutes, the test piece was taken out and the coated surface was observed. ○ ・ ・ ・ ・ Complete dissolution △ ・ ・ ・ ・ ・ ・ Undissolved part remains × ・ ・ ・ ・ ・ ・ Not dissolved * 3, 4, 5 Water resistance, solvent resistance, alkali resistance: Water, acetone, 1 % Sodium hydroxide aqueous solution, and the cured coating film was rubbed 20 times and evaluated according to the degree of decrease in film thickness. ◎ ・ ・ ・ ・ ・ ・ No change ○ ・ ・ ・ ・ ・ ・ 1-5μm △ ・ ・ ・ ・ 5-10μm × ・ ・ ・ ・ ・ ・ 10μm or more * 6 The coating film of Example 3 was cured by irradiating 5 Mrads of electron beam. A coating was obtained.

As is evident from Table 1, the resin composition of the present invention can be dissolved in a dilute aqueous alkali solution, and therefore has no effect on the environment or working steps. Excellent alkali resistance.

[0025]

The radiation-curable resin composition of the present invention can be dissolved in a dilute aqueous alkali solution, and the cured coating film has excellent water resistance, solvent resistance, chemical resistance, etc.
It is extremely useful in a wide range of applications such as photoresists, printing inks, plate making materials and the like.

──────────────────────────────────────────────────の Continuation of the front page (51) Int.Cl. ⁷ identification code FI C09D 175/16 C09D 175/16 (58) Field surveyed (Int.Cl. ⁷ , DB name) C08F 290/00-290/14 C08F 299/00-299/08 C08G 18/42 C08G 18/67 C09D 1/00-201/10

Claims (1)

(57) [Claims] (1) a polyol compound (a) and a compound (b) represented by the formula (1): (Where a and b are each a number from 0 to 10, and a + b
Is 0.5 to 20. Urethane (meth) acrylate (A) which is a reaction product of an organic polyisocyanate (c) and a hydroxyl group-containing (meth) acrylate (d),
A radiation-curable resin composition comprising a reactive diluent (B) and a photopolymerization initiator (C) as an optional component.