JPH10237144A - Active-energy ray-hardenable resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject resin composition capable of providing a resin molding product excellent in transparency and good in flexibility, by formulating a specific urethane polymer, a carbonate di(meth)acrylate having a specified structure, a polyester (meth)acrylate, a specific aliphatic polythiol compound and an active energy ray initiator. SOLUTION: The objective composition is obtained by formulating (A) 30-80wt.% urethane polymer having two or more (meth)acryloyloxy groups in one molecule, (B) 10-60wt.% compound of the formula [R<1> and R<2> are each H, etc.; R<3> and R<4> are each a 2-5C saturated hydrocarbon; (k) is 1-5; (m) and (n) are each 0-5], (e.g. diethylene glycol disallyl carbonate), (C) 10-60wt.% polyester (meth)acrylate, (D) 1-20wt.% aliphatic polythiol compound having two or more thiol groups in the molecule, and (E) 0.01-5wt.% active energy ray initiator.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an active energy ray-curable resin composition, and more particularly, to a composition having excellent transparency.
The present invention also relates to an active energy ray-curable resin composition capable of obtaining a resin molded article having high flexibility.

[0002]

2. Description of the Related Art As a method of manufacturing a resin molded product, a method of injection molding a thermoplastic polymer is generally known. This method is preferable as a method of mass-producing molded products having a certain shape with good productivity, but when molding a small number of various kinds of articles, the metal mold is expensive, so casting is performed. A method of manufacturing a resin molded product in which a liquid resin is poured into a silicone rubber mold and cured by a method is used.

As a liquid resin used in the casting method, a thermosetting resin has been mainly used. Recently, an active energy ray curing casting method having higher productivity has been proposed (see, for example, Japanese Patent Application Laid-Open (kokai) No. H10-157572). JP-A-7-124962). In this method, a molded product is obtained by injecting an active energy ray-curable liquid resin into a transparent silicone rubber mold, irradiating an active energy ray from the outside of the silicone rubber mold and curing the resin. However, the resin molded product obtained by this method has excellent physical properties, but has insufficient transparency and flexibility.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a resin molded product having excellent transparency and flexibility in the production of a resin molded product by an active energy ray curing casting method. An object of the present invention is to provide an active energy ray-curable resin composition.

[0005]

Means for Solving the Problems The present inventors have conducted intensive studies to achieve the above object, and as a result, have found that a urethane polymer having two or more (meth) acryloyloxy groups in one molecule, a carbonate diene having a specific structure, A resin composition containing (meth) acrylate, polyester (meth) acrylate, an aliphatic polythiol compound having at least two thiol groups in a molecule, and an active energy ray initiator in a specific ratio has the above object. The inventors have found what can be achieved and completed the present invention.

That is, the present invention relates to (A) 30 to 80% by weight of a urethane polymer having two or more (meth) acryloyloxy groups in one molecule, (B) the following general formula (I)
10 to 60% by weight of a compound represented by

Embedded image (C) 10 to 60% by weight of a polyester (meth) acrylate, (D) 1 to 20% by weight of an aliphatic polythiol compound having at least two thiol groups in a molecule, and (E) an active energy ray initiator. 01-5% by weight,
An active energy ray-curable resin composition comprising:

[0007]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in detail. First, each component of the active energy ray-curable resin composition of the present invention (hereinafter, referred to as a curable resin composition) will be described.

Component (A) The component (A), a urethane polymer having two or more (meth) acryloyloxy groups in one molecule, is a component that imparts flexibility and impact resistance to a cured resin molded product. Specifically, a polyisocyanate having two or more isocyanate groups in the molecule has a main chain skeleton of a polyether,
It is obtained by reacting a diol such as polyester or polycarbonate, and then reacting the remaining isocyanate group with a (meth) acrylate containing a hydroxyl group. Those having a molecular weight of 1500 or more are preferred.

Specific examples of the polyisocyanate compound include 1,6-hexamethylene diisocyanate, tris (isocyanatohexyl) isocyanurate, 1,4-
Tetramethylene diisocyanate, 2,2,4-trimethylhexamethylene diisoanate, cyclohexane diisocyanate, isophorone diisocyanate, bis (4,4'-isocyanatocyclohexyl) methane, bis (4,4'-isocyanatocyclohexyl) propane, , 3-bis (isocyanatomethyl) cyclohexane, meta-xylylene diisocyanate, para-xylylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, (4,4'-
Examples include isocyanatophenyl) methane and naphthalenediisocyanate. Among the above, tris (isocyanatohexyl) isocyanurate, isophorone diisocyanate, bis (4,4′-isocyanatocyclohexyl) methane, 1,3-bis (isocyanate) (Natomethyl) cyclohexane, meta-xylylene diisocyanate, 2,4-tolylene diisocyanate, and 2,6-tolylene diisocyanate are particularly preferred.

Specific examples of the diol compound include those having an ether bond in the main chain, such as polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, modified polytetramethylene ether glycol, polycaprolactone diol, dihydric alcohol and dibasic alcohol. Examples thereof include those having an ester bond in the main chain such as a polyester diol synthesized from an acid, and those having a carbonate bond in the main chain synthesized by reacting a dihydric alcohol with phosgene or dimethyl carbonate.

Specific examples of the (meth) acrylate having a hydroxyl group include 2-hydroxyethyl (meth) acrylate.
Acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxybutyl (meth) acrylate,
In addition to 4-hydroxybutyl (meth) acrylate and the like, a reaction product of a monoepoxy compound such as butyl glycidyl ether, 2-ethylhexyl glycidyl ether, and glycidyl methacrylate with (meth) acrylic acid, and a mono (meth) acrylate of polyethylene glycol and polypropylene glycol A) acrylates and mono (meth) acrylates of polycaprolactone diol.

The reaction between the polyisocyanate and various diols or (meth) acrylates containing hydroxyl groups is carried out in the presence of a tin-based catalyst such as di-n-butyltin dilaurate, so that the isocyanate groups and hydroxyl groups become almost equivalent. And heating at 60-70 ° C. for several hours. Since the reactants generally become highly viscous, it is preferable to dilute with another low-viscosity monomer during or after the reaction.

The proportion of the component (A) used is (A) to (E)
The content is 30 to 80% by weight, preferably 40 to 70% by weight in the curable resin composition comprising the components. (A) The amount of the component is 3
If the amount is less than 0% by weight, sufficient flexibility cannot be obtained, and if the amount exceeds 80% by weight, the monomer composition becomes highly viscous, and not only does the workability of injection into a silicone mold deteriorate, but also the curing by irradiation with active energy rays. At times, peeling from the silicone mold occurs, so that the surface accuracy of the molded product cannot be obtained.

Component (B) The compound represented by the above general formula (I), which is the component (B), is a polyethylene glycol having a degree of polymerization (k and n in the general formula (I)) of 1 to 5, An aliphatic diallyl carbonate obtained by reacting polypropylene glycol, polybutylene glycol, or poly (methylbutylene) glycol with phosgene or dimethyl carbonate, and (meth) allyl alcohol. (B)
The most preferred compound as a component is diethylene glycol bisallyl carbonate.

The amount of the component (B) used is 10 to 60% by weight, preferably 15 to 30% by weight in the curable resin composition comprising the components (A) to (E). (B) The amount of the component is 10
If the content is less than the weight percentage, the silicone resin is separated from the silicone mold at the time of curing by irradiation with active energy rays, so that the surface accuracy of the molded product cannot be obtained. On the other hand, when the content exceeds 60% by weight, the curability by irradiation with active energy rays is remarkably reduced, and the productivity becomes poor.

Component (C) The component (C), a polyester (meth) acrylate, is a component for improving the transparency of a molded article. Specifically, a polybasic acid, a polyhydric alcohol and (meth) acrylic It is synthesized by a dehydration polycondensation reaction with an acid.

Specific examples of the polybasic acid include phthalic anhydride, isophthalic acid, terephthalic acid, adipic acid, tetrachlorophthalic anhydride, tetrabromophthalic anhydride, tetrahydrophthalic anhydride, hexahydrophthalic anhydride, hexic acid, and succinic acid. Acid, sebacic acid, trimellitic acid, fumaric acid, maleic anhydride, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-
And cyclohexanedicarboxylic acid.

Specific examples of polyhydric alcohols include ethylene glycol, propylene glycol, 1,4-butanediol, 1,3-butanediol, 2,3-butanediol, diethylene glycol, dipropylene glycol, triethylene glycol, , 5-pentanediol, 1,6-hexanediol, neopentyl glycol, hydrogenated bisphenol A, glycerin, pentaerythritol, trimethylolpropane, trimethylolethane, 1,4-cyclohexanedimethanol, 2,2
4-trimethyl-1,3-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, hydroxybivalyl hydroxybivalate, 3-methyl-1,5
-Pentanediol, 2-methyl-1,8-octanediol, 1,9-nonanediol, 2-methyl-1,3
-Propanediol and the like.

The amount of the component (C) used is 10 to 60% by weight, preferably 15 to 30% by weight in the curable resin composition comprising the components (A) to (E). (B) The amount of the component is 10
If the amount is less than 60% by weight, sufficient transparency of the molded article cannot be obtained, and if it exceeds 60% by weight, sufficient flexibility of the molded article cannot be obtained.

Component (D) The component (D), an aliphatic polythiol compound having at least two thiol groups in the molecule, is a component for improving the curability upon curing by irradiation with active energy rays. . Specific examples include 1,2-ethylenedithioglycol, 1,2-propylenedithioglycol, 1,4-
Butylene dithioglycol, di (2-mercaptoethyl) thiol, ethylene glycol dithioglycolate, 1,2-propylene glycol dithioglycolate, 1,4-butanediol dithioglycolate, trimethylolpropane tris (thioglycolate), penta Erythritol tetrakis (thioglycolate), ethylene glycol dithiopropionate, 1,2-propylene glycol dithiopropionate, 1,4-butanediol dithiopropionate, trimethylolpropane tris (β-thiopropionate), Pentaerythritol tetrakis (β-thiopropionate), dipentaerythritol hexakis (β-thiopropionate) and the like can be mentioned. Among them, trimethylolpropane tris (β-thiopropionate) and pentaerythritol tetrakis (β-thiopropionate) are preferable because they have little odor peculiar to polythiol.

The proportion of the component (D) used is (A) to (E)
It is 1 to 20% by weight, preferably 5 to 15% by weight in the curable resin composition comprising the components. If the amount of the component (D) is less than 1% by weight, the curability at the time of curing is reduced, and if it exceeds 20% by weight, coloring of a molded article is caused.

Regarding the component (E) As the active energy ray initiator which is the component (E),
Those which generate a radical source mainly in response to ultraviolet rays having a wavelength of 200 to 400 nm are preferred. Specific examples include benzoin, benzoin monomethyl ether, benzoin propyl ether, acetoin, benzyl, benzophenone, p-methoxybenzophenone, diethoxyacetophenone, and benzyl. Carbonyl compounds such as dimethyl ketal, 2,2-diethoxyacetophenone, 1-hydroxycyclohexylphenyl ketone, methylphenylglyoxylate, ethylphenylglyoxylate, 2-hydroxy-2-methyl-1-phenylpropan-1-one , Tetramethylthiuram monosulfide, sulfur compounds such as tetramethylthiuram disulfide, 2,4,
Acylphosphine oxides such as 6-trimethylbenzoyldiphenylphosphine oxide and the like can be mentioned. These are used in one kind or in a mixture of two or more kinds. Among them, benzophenone, benzoin isopropyl ether, methylphenylglyoxylate, 1-hydroxycyclohexylphenyl ketone, benzyldimethylketal, and 2,4,6-trimethylbenzoyldiphenylphosphine oxide are particularly preferable.

The amount of component (E) used is 0.01 to 5% by weight, preferably 0.02 to 2% by weight, based on the curable resin composition comprising components (A) to (E). If the amount of the component (E) is less than 0.01% by weight, the curability is insufficient, and if it exceeds 5% by weight, not only does the deep part curability deteriorate, but also the coloring of the molded product is caused.

The active energy ray-curable resin composition of the present invention may contain, if necessary, an organic peroxide, an antioxidant, an anti-yellowing agent, an ultraviolet absorber, an organic dye, a pigment, an inorganic filler, and an anti-settling agent. And an additive such as an antifoaming agent.

In practicing the present invention, the curable resin composition is poured into a transparent silicone rubber mold and irradiated with an active energy ray from a light source such as a sun, a chemical lamp, a high-pressure mercury lamp, or a metal halide lamp. The irradiation dose is 20
0.1 to 30 J / c as an integrated value of ultraviolet light of 0 to 400 nm
m ² . The irradiation atmosphere may be air or an inert gas such as nitrogen or argon. Further, irradiation and heating may be combined.

[0026]

The present invention will be described below in more detail with reference to examples and comparative examples. The evaluation of the physical properties in Examples and Comparative Examples was performed by the following methods.

(1) Appearance of Molded Article The produced molded plate was visually observed and judged. ：: The silicone rubber mold surface is accurately transferred and good. ：: There is a trace of polymerization peeling on the entire surface or a part of the surface, or the adhesiveness remains on the surface of the molded product.

(2) Total light transmittance Measured in accordance with ASTM D1003-61.

(3) Haze Measured according to ASTM D1003-61.

(4) Flexibility Judgment was made based on the presence or absence of breakage when the produced flat plate (thickness: 3 mm) was bent at 180 degrees. ○: No destruction ×: Destruction

(5) Workability of Injection Workability of workability of injecting the resin composition into the silicone rubber mold was determined as good or bad. ：: easy to inject. ×: Difficult to inject.

The abbreviations used in the examples and comparative examples represent the following compounds. PUM-1: Isophorone diisocyanate, polytetramethylene ether glycol (number-average molecular weight 650) and 2-hydroxypropyl methacrylate 5: 2.
Polyurethane dimethacrylate PUM-2 obtained by reacting at a molar ratio of 5: 5.25 with modified polytetramethylene ether glycol (number average molecular weight 100
0) and 2-hydroxypropyl methacrylate in a molar ratio of 5: 2.5: 5.25 to obtain a polyurethane dimethacrylate UM-1: isophorone diisocyanate and 2-hydroxypropyl methacrylate in a ratio of 1: 2.1. Urethane dimethacrylate obtained by reacting at a molar ratio UM-2: Urethane dimethacrylate obtained by reacting tolylene diisocyanate with 2-hydroxypropyl methacrylate at a molar ratio of 1: 2.1 2GDMA: Diethylene glycol dimethacrylate PESA : Polyester acrylate (trifunctional or more)
(Trade name: Aronix M8030, manufactured by Toagosei Chemical Industry Co., Ltd.) DGBA: diethylene glycol bisallyl carbonate TMTP: trimethylolpropane tris (β-thiopropionate) BNP: benzophenone

[Example 1] (a) Production of silicone rubber mold An acrylic plate (manufactured by Mitsubishi Rayon Co., Ltd., trade name: Acrylite (registered trademark) L) having a width of 30 mm, a length of 150 mm and a thickness of 3 mm was used. Put into a box-shaped outer frame with an opening of 70 mm x 70 mm and a depth of 180 mm made of an acrylic plate having a thickness of 2 mm, and put a silicone rubber resin liquid (Shin-Etsu Chemical Co., Ltd.)
Manufactured by KE-1606), and cured by standing at room temperature for 15 hours. The transparent silicone rubber was cut with a cutter knife, and the acrylic plate was taken out to prepare a silicone rubber mold for casting.

(B) Preparation of curable resin composition 54 g of polyurethane dimethacrylate (PUM-2)
Diethylene glycol bisallyl carbonate (DGB
A, trade name: CR-39 (manufactured by PPG Corporation)) 18 g,
Polyester acrylate (PESA, trade name: Aronix M8030 (manufactured by Toa Gosei Chemical Industry Co., Ltd.)) 18
g, trimethylolpropane tris (β-thiopropionate) (TMTP, trade name: TMTP (Yodo Chemical Co., Ltd.)
9) and 1 g of benzophenone (BNP) were mixed and stirred well at room temperature to prepare a curable resin composition.

(C) Preparation of Resin Molded Product The curable resin composition was poured into a silicone rubber mold at room temperature and normal pressure, and was cured by irradiating ultraviolet rays with a chemical lamp for about 30 minutes (irradiation amount: 340 to 380 nm). UV integrated energy is 4 J / cm ² ). Next, the cured product was taken out of the silicone rubber mold, and the width was 30 mm × length 15 mm.
A molded plate of 0 mm × thickness of 3 mm was obtained. Table 2 shows the evaluation results of the physical properties.

[Examples 2 to 4] Table 1 shows the curable resin compositions.
A molded plate was prepared in the same manner as in Example 1 except that the modified plate was used as shown in Table 1, and the physical properties were evaluated in the same manner as in Example 1. Table 2 shows the evaluation results of the physical properties.

Comparative Examples 1 to 7 Curable resin compositions are shown in Table 1.
A molded plate was prepared in the same manner as in Example 1 except that the modified plate was used as shown in Table 1, and the physical properties were evaluated in the same manner as in Example 1. Table 2 shows the evaluation results of the physical properties.

[0038]

[Table 1]

[0039]

[Table 2]

[0040]

【The invention's effect】

(1) Since the curable resin composition of the present invention has excellent curability by active energy rays, a resin molded product can be easily obtained by a cast polymerization method using light. (2) The resin molded product obtained by using the curable resin composition of the present invention has excellent transparency and high flexibility, and is useful as a material for a soft aspheric lens or the like.

Claims (1)

[Claims] 1. A urethane polymer having two or more (meth) acryloyloxy groups in one molecule of (A) 30 to 80.
(B) 10 to 60% by weight of a compound represented by the following general formula (I): (C) 10 to 60% by weight of a polyester (meth) acrylate, (D) 1 to 20% by weight of an aliphatic polythiol compound having at least two thiol groups in a molecule, and (E) an active energy ray initiator. An active energy ray-curable resin composition comprising from 0.01 to 5% by weight.