JPH06206956A - Radiation-curable resin composition and its cured product - Google Patents

Abstract

PURPOSE:To provide a radiation-curable resin composition containing a specific urethane (meth)acrylate, a reactive diluent and a photo-polymerization initiator, soluble in dilute alkaline aqueous solution, having excellent water-resistance, solvent resistance and chemical resistance and useful for coating agent, photoresist, etc. CONSTITUTION:The composition contains (A) preferably 39-80wt.% of a urethane (meth)acrylate obtained by reacting (i) a >=3-functional polyol compound such as glycerol with (ii) a polybasic acid anhydride such as maleic anhydride and reacting (iii) the obtained compound having one or more carboxyl groups and two or more hydroxyl groups in one molecule with (iv) an organic polyisocyanate such as tolylene diisocyanate and (v) a hydroxyl-containing (meth) acrylate such as 2-hydroxyethyl (meth) acrylate, (B) preferably 20-60wt.% of a reactive diluent such as 2-hydroxyethyl (meth) acrylate and (C) preferably 0-10wt.% of a photo-polymerization initiator as an arbitrary component.

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art Radiation curable resin compositions curable with ultraviolet rays or electron beams are widely used in applications such as inks, paints and adhesives from the viewpoint of no pollution and energy saving. Although organic solvents are used for cleaning printing machines and coating machines after using these inks, paints, etc., the demand for converting the cleaning solution into a water-based system is increasing with the recent increase in environmental problems. Nevertheless, the fact is that a satisfactory water-soluble radiation-curable resin composition has not yet been obtained.

[0003]

Development with a resin composition in which the problems in the prior art as described above are improved, that is, a dilute aqueous alkali solution (for example, an aqueous solution of caustic soda, caustic potash, sodium carbonate, ammonia, amines, etc.) is used. 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 has excellent water resistance, solvent resistance, chemical resistance and the like.

[0004]

Means for Solving the Problems As a result of intensive studies, the present inventor has found that by using a specific compound having a carboxyl group and a (meth) acryloyl group in a molecule, the compound has compatibility and is stable in storage. The inventors have found a resin composition having excellent properties, capable of being dissolved and removed with a dilute alkaline aqueous solution, and having a cured product having excellent water resistance, solvent resistance, chemical resistance, etc., and have completed the present invention.

That is, the present invention is a reaction product of a trifunctional or higher functional polyol compound (a) and a polybasic acid anhydride (b),
Compound (c) having at least one carboxyl group and at least two hydroxyl groups in the molecule, organic polyisocyanate (d), and hydroxyl group-containing (meth) acrylate (e)
A radiation-curable resin composition and a cured product containing a urethane (meth) acrylate (A) which is a reaction product with a reactive diluent (B) and a photopolymerization initiator (C) as an optional component. Regarding

In the present invention, a reaction product of a compound (c) having at least one carboxyl group and at least two hydroxyl groups in the molecule, an organic polyisocyanate (d) and a hydroxyl group-containing (meth) acrylate (e). A urethane (meth) acrylate (A) is used. Specific examples of the compound (c) having at least one carboxyl group and at least two hydroxyl groups in the molecule which is a raw material of the urethane (meth) acrylate (A) include, for example, trifunctional or higher functional polyol compounds (a ) (For example, glycerin, trimethylolpropane, trimethylolethane,
Glycerin polypropoxytriol, trimethylolpropane polyethoxytriol, pentaerythritol polypropoxytetraol, trimethylolpropane ε-caprolactone modified product, trimethylolpropane and succinic acid, maleic acid, adipic acid, tetrahydrophthalic acid, etc. Polybasic acid anhydride (b) (for example, succinic anhydride, maleic anhydride, itaconic anhydride, phthalic anhydride) with respect to 1 equivalent of hydroxyl group of polybasic acid or a polyester polyol which is a reaction product of its anhydride , Tetrahydrophthalic anhydride, hexahydrophthalic anhydride, etc.) and the like.

Specific examples of the organic polyisocyanate (d) include, for example, 2,4-tolylene diisocyanate,
Examples thereof include 2,6-tolylenediisocyanate, xylylene diisocyanate, diphenylmethane-4,4'-diisocyanate, dicyclohexylmethane diisocyanate, isophorone diisocyanate and hexamethylene diisocyanate.

Specific examples of the hydroxyl group-containing (meth) acrylate (e) include 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate and polyethylene glycol mono. (Meth) acrylate, pentaerythritol tri (meth) acrylate,
Examples thereof include glycerin di (meth) acrylate, tris (2-hydroxyethyl) isocyanurate di (meth) acrylate and N-methylol (meth) acrylamide.

The reaction between the compound (c) and the organic polyisocyanate (d) is carried out by reacting 1.1 to 2.0 equivalents of the isocyanate group of the organic polyisocyanate (d) with 1 equivalent of the hydroxyl group of the compound (c). It is preferable to react. The reaction temperature is preferably 60 to 100 ° C., particularly preferably 75.
~ 85 ° C. The reaction time is preferably 5 to 20 hours.
Then, with respect to 1 equivalent of the isocyanate group of the reaction product of the compound (c) and the organic polyisocyanate (d), the hydroxyl group of the hydroxyl group-containing (meth) acrylate (e), preferably 0.95 to 1.2 equivalents, is reacted. Then, urethane (meth) acrylate (A) can be obtained. In order to prevent this polymerization, it is preferable to use a polymerization inhibitor such as methylhydroquinone, p-methoxyphenol and hydroquinone. The amount of the polymerization inhibitor used is preferably 0.01 to 0.5% by weight based on the reaction mixture. The reaction temperature is preferably 60 to 100 ° C., particularly preferably 7
5 to 85 ° C. The reaction time is preferably 5 to 20 hours.

Specific examples of the reactive diluent (B) used in the present invention include a wide range of monofunctional to polyfunctional ones. Among them, particularly preferable ones are 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, tris (2
Examples thereof include water-soluble ones such as -hydroxyethyl) isocyanurate di (meth) acrylate.

Next, specific examples of the photopolymerization initiator (C) which can be used as an optional component include 1-hydroxycyclohexyl phenyl ketone, benzophenone and 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-propylketone) and the like can be mentioned. These may be used alone or in combination of two or more.

Further, the photopolymerization initiator is N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, triethanolamine,
A known and conventional photopolymerization accelerator such as triethylamine can be used in combination.

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

The proportion of each component used in the present invention is preferably 29 to 95% by weight of the component (A), and particularly preferably 39 to 95% by weight.
80% by weight, component (B) is preferably 5 to 70% by weight, particularly preferably 20 to 60% by weight, (C)
The component is preferably 0 to 15% by weight, particularly preferably 0 to
It is 10% by weight.

The radiation-curable resin composition of the present invention may further contain, if necessary, within the range not deviating from the object of the present invention, in particular, solubility in dilute aqueous alkali solution, storage stability, and water resistance and solvent resistance of the cured product. Well-known and commonly used organic solvent inorganic fillers, additives and the like can be added within a range capable of retaining chemical resistance and the like.

In the present invention, radiation means electron beam, α ray,
It is a collective term for ionizing radiation and light such as β rays, γ rays, X rays, neutron rays, and ultraviolet rays. The cured product of the radiation curable resin composition of the present invention can be obtained by irradiating the above-mentioned radiation to cure the cured product according to a conventional method. The resin composition of the present invention is useful, for example, in paints, adhesives, printing inks, plate-making materials, coatings, photoresists and the like.

[0017]

EXAMPLES Next, the present invention will be described in more detail by way of examples. In the following, all parts are by weight unless otherwise specified.

Synthesis Example 1 Polypropoxytriol of glycerin (hydroxyl number 441
mgKOH / g, molecular weight 382) 382 parts, succinic anhydride 10
Charge 0 parts, heat to 90 ° C., react for about 10 hours,
A reaction product (C-1) having an acid value (mgKOH / g) of 116 and a hydroxyl value (mgKOH / g) of 233 was obtained. Then, 482 parts of the above reaction product and 444.4 parts of isophorone diisocyanate were charged,
After reacting at 0 ° C for about 10 hours, 243.6 parts of 2-hydroxyethyl acrylate and 0.6 parts of p-methoxyphenol were charged and reacted at 80 ° C for about 15 hours to obtain urethane acrylate (A-1). Acid value (mgKOH / g) was 48.0

Synthesis Example 2 500 parts of trimethylolpropane polypropoxytriol (hydroxyl number, 337 mg KOH / g, molecular weight 500),
Charge 98 parts of maleic anhydride and heat to 90 ° C.
After reacting for 0 hours, acid value (mgKOH / g) 94 and hydroxyl value (mgKOH / g)
g) 188, a reaction product (C-2) was obtained. Next, 598 parts of the above reaction product and 348 parts of tolylene diisocyanate were charged and reacted at 80 ° C. for about 10 hours, then 243.6 parts of 2-hydroxyethyl acrylate and 0.6 part of p-methoxyphenol were charged, and at 80 ° C. The reaction was carried out for 15 hours to obtain urethane acrylate (A-2). Acid value (mg
KOH / g) was 47.0.

Synthesis Example 3 400 parts of an ε-caprolactone modified product of trimethylolpropane (hydroxyl number 421 mgKOH / g, molecular weight 400) and 98 parts of maleic anhydride were charged and heated to 90 ° C. to about 10
After reacting for a time, acid value (mgKOH / g) 112.7, hydroxyl value (mg
The reaction product (C-3) of KOH / g) 225.3 was obtained. Then, 498 parts of the above reaction product, and isophorone diisocyanate 44
4.4 parts were charged and reacted at 80 ° C. for about 10 hours, and then 2-hydroxyethyl acrylate 243.6 parts, p
-Prepare 0.6 parts of methoxyphenol, about 1 at 80 ℃
After reacting for 5 hours, urethane acrylate (A-3) was obtained. The acid value (mgKOH / g) was 47.3.

Examples 1 to 4 The respective components (numerical values indicate parts by weight) were dissolved and mixed in the proportions shown in Table 1 to obtain the radiation curable resin composition of the present invention. Using a wire bar, this radiation curable resin composition was applied to chin-free steel so that the thickness of each was 20 μm, and was irradiated with ultraviolet rays from a high pressure mercury lamp to cure the composition to obtain a test piece. Using this test piece, water resistance, solvent resistance, alkali resistance and solubility of the composition in a dilute alkaline aqueous solution were tested. The results are shown in Table 1.

[0022]

[Table 1] Table 1 Example * 6 1 2 3 4 Urethane acrylate (A-1) 50 Urethane acrylate (A-2) 40 30 Urethane acrylate (A-3) 60 30 Polyethylene glycol diacrylate 20 20 30 Acryloyl morpholine 30 30 30 2-hydroxyethyl acrylate 20 10 10 Irgacure 184 * 1 5 5-5 Solubility in dilute aqueous alkali solution * 2 ○ ○ ○ ○ Cured coating water resistance * 3 ◎ ◎ ◎ ◎ Solvent resistance * 4 ◎ ◎ ◎ ◎ ◎ Alkali resistance * 5 ◎ ◎ ○ ○

Note * 1. Irgacure 184: Ciba Geigy photopolymerization initiator, 1-hydroxy-cyclohexyl-phenyl ketone * 2. Solubility in dilute alkaline aqueous solution: Using a wire bar, each was applied to chin-free steel so as to have a thickness of 20 μm, immersed in an aqueous 1.5% sodium carbonate solution for 10 minutes, and then the test piece was taken out and the coated surface was observed. . ○ ・ ・ ・ ・ Complete dissolution △ ・ ・ ・ ・ Insoluble portion remains × ・ ・ ・ ・ No dissolution * 3,4,5 (water resistance, solvent resistance, alkali resistance): Gauze, water and acetone, respectively Evaluation was made according to the degree of reduction in film thickness after rubbing the cured coating film 20 times with a 1% aqueous sodium hydroxide solution. ◎ ・ ・ ・ No change ○ ・ ・ ・ ・ 1-5 μm △ ・ ・ ・ ・ 5-10 μm × ・ ・ ・ ・ 10 μm or more * 6. In Example 3, an electron beam was irradiated with 5 megarads instead of UV irradiation to obtain a cured coating film.

As is apparent from Table 1, the resin composition of the present invention can be dissolved in a dilute alkaline aqueous solution, has no effect on the environment or working steps, and its cured product (coating film) is
It has excellent water resistance, solvent resistance, and alkali resistance.

[0025]

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

Claims (2)

[Claims] 1. A reaction product of a trifunctional or higher functional polyol compound (a) and a polybasic acid anhydride (b), wherein at least 1 is present in the molecule.
Urethane (meth) acrylate (A), which is a reaction product of a compound (c) having one carboxyl group and at least two hydroxyl groups, an organic polyisocyanate (d), and a hydroxyl group-containing (meth) acrylate (e), Diluent (B)
And a photopolymerization initiator (C) as an optional component, which is a radiation-curable resin composition. 2. A cured product of the radiation curable resin composition according to claim 1.