JPH05287040A - Ultraviolet-curing resin composition for transmission screen and its cured product - Google Patents

Abstract

PURPOSE:To provide the title composition which can give a cured product having a high refractive index and excellent adhesion to a substrate, mold release, reproducibility of form, restorability and scuffing resistance. CONSTITUTION:The title composition comprises 20-50wt.% bisphenol A epoxy (meth)acrylate of a molecular weight of 1000 or above, 40-70wt.% monofunctional reactive monomer, 5-25wt.% bifunctional reactive monomer, and 0.5-10wt.% photopolymerization initiator.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a video projector,
The present invention relates to an ultraviolet curable resin composition suitable for a transmissive screen such as a Fresnel lens or a lenticular lens used in a projection television, and a cured product thereof.

[0002]

2. Description of the Related Art Conventionally, this type of lens has been formed by a method such as a pressing method or a casting method. The former pressing method had poor productivity because it was manufactured by a cycle of heating, pressurizing and cooling. In addition, the latter casting method requires a long manufacturing time because a monomer is poured into a mold for polymerization, and a large number of molds are required. Therefore, recently, a lens mold and a transparent resin substrate (for example, polycarbonate, vinyl chloride, polyester) are used. , Acrylic, styrene, etc.) and a UV-curable resin liquid for forming a lens portion is interposed between them to irradiate ultraviolet rays to integrally cure the lens portion.
(For example, JP-A-61-177215 and JP-A-61-2)
48707, JP-A-61-248708, JP-A-63-
163330, JP-A-63-167301, JP-A-63
-199302, see JP-A-64-6935, etc.)

[0003]

In the technique of forming a lens part by interposing an ultraviolet curable resin between the lens mold and the transparent resin base material, it is sufficient to provide sufficient space between the lens part and the transparent resin base material. Adhesion is often not obtained. In particular, when a resin containing a methacrylic resin, which is excellent in transparency and weather resistance and is suitable as a material of this type, is used as a substrate, the adhesiveness with the ultraviolet curable resin is insufficient, and thus the adhesiveness It is strongly desired to increase Further, no proposal has been made to meet the demand for thinning projection televisions and the like.

[0004]

[Means for Solving the Problems] In order to solve the above-mentioned problems, the inventors of the present invention have conducted extensive studies and as a result, have found that curing by ultraviolet rays is fast and that the resin substrate, particularly methacrylic resin, has excellent adhesiveness The inventors have found a resin composition having a high refractive index and completed the present invention. That is, the present invention has a molecular weight of 1
000 or more bisphenol A type epoxy (meth) acrylate (A) 20 to 50% by weight, monofunctional reactive monomer (B) 40 to 70% by weight, bifunctional reactive monomer (C) 5
To 25% by weight and 0.5 to 10% by weight of a photopolymerization initiator (D), the present invention relates to an ultraviolet curable resin composition for a transmissive screen and a cured product thereof.

Bisphenol A type epoxy (meth) acrylate (A) having a molecular weight of 1000 or more used in the present invention
As a specific example, for example, bisphenol A type epoxy resin (for example, manufactured by Yuka Shell Epoxy Co., Ltd., Epicoat 1001 (epoxy equivalent 450-500), Epicoat 1003 (epoxy equivalent 670-770), Epicoat 1004 (epoxy equivalent). 875-975) and the like. } And (meth) acrylic acid. (Meth) acrylic acid is preferably reacted in a ratio of about 0.7 to 1.5 equivalents, particularly preferably about 0.9 to 1.1 equivalents, relative to 1 equivalent of epoxy groups of the bisphenol A type epoxy resin, Monofunctional reactive monomer that is the component (B) during the reaction (for example, dicyclopentadieneoxyethyl (meth) acrylate (manufactured by Hitachi Chemical Co., Ltd., FA-512A, FA-5
12M) tetrahydrofurfuryl (meth) acrylate, carbitol (meth) acrylate, phenoxyethyl (meth) acrylate, phenylpolyethoxy (meth) acrylate, isobornyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, phenylglycidyl ether. (Meth) acrylate, N-
Vinyl caprolactam, acryloyl morpholine, polyethoxy (meth) acrylate of 0-phenylphenol, polyethoxy (meth) acrylate of p-phenylphenol, o-phenylphenoxyethyl (meth) acrylate, tribromophenoxyethyl (meth) acrylate, tri Bromobenzyl (meth) acrylate,
Etc. is preferably used. In order to accelerate the reaction, it is preferable to use a catalyst (eg, triethylamine, benzyldimethylamine, methyltriethylammonium chloride, triphenylstibine, triphenylphosphine, etc.), and the amount of the catalyst used is based on the reaction raw material mixture. It is preferably used in the range of 0.1 to 10% by weight. In order to prevent the polymerization during the reaction, it is preferable to use a polymerization inhibitor (for example, metoquinone, hydroquinone, phenothiazine, etc.), and the amount thereof is 0.01 to 1% by weight based on the reaction raw material mixture. Preferably. The reaction temperature is 60 to 150 ° C., and the reaction time is usually 5 to 60 hours.

In the resin composition of the present invention, the component (A) is used in an amount of 20 to 50% by weight, preferably 20 to 40% by weight. When it is used in an amount of 50% by weight or more, the viscosity of the resin composition becomes high and the coating property becomes poor.
On the other hand, if it is 20% by weight or less, the adhesion to the methacrylic resin base material becomes poor and the refractive index of the resin composition also becomes low.

Specific examples of the monofunctional reactive monomer (B) are as described above, and particularly preferable ones are, for example, acrylates of phenylglycidyl ether (manufactured by Nippon Kayaku Co., Ltd., KAYARAD R-128H). ), Phenoxyethyl acrylate, phenyl polyethoxy acrylate (n =
1 to 4), dicyclopentadieneoxyethyl acrylate, o-phenylphenol poly (n = 1 to 4) ethoxy acrylate, tribromophenyloxyethyl acrylate, and the like, which have a high refractive index.

In the resin composition of the present invention, the component (B) is used in an amount of 40 to 70% by weight, preferably 40 to 60% by weight. If it is used in an amount of 70% by weight or more, the cured product of the resin composition will have poor demolding properties, restorability and scratch resistance, and if it is 40% by weight or less, the adhesion to the methacrylic resin substrate will be poor.

Specific examples of the bifunctional reactive monomer (C) include, for example, polyethoxydi (meth) bisphenol A.
Acrylate, polyethoxydi (meth) acrylate of bisphenol F, polyethoxydi (meth) acrylate of tetrabromobisphenol A, di (meth) acrylate of ε-caprolactone adduct of neopentyl glycol hydroxypivalate, 1,6-hexanediol di (meth) ) Acrylate, 1,9-nonanediol (meth) acrylate, polyethylene glycol di (meth) acrylate and the like can be mentioned. Particularly preferred are those having a high refractive index such as bisphenol A tetraethoxydiacrylate and bisphenol A poly (n = 9 to 15) ethoxydiacrylate.

In the resin composition of the present invention, the component (C) is used in an amount of 5 to 30% by weight, preferably 5 to 25% by weight. If it is used in an amount of 30% by weight or more, the adhesion to the methacrylic resin substrate will be poor, and if it is 5% by weight or less, the cured product of the resin composition will be poor in resilience and scratch resistance.

The photopolymerization initiator (D) is, for example,

[0012]

[Chemical 1]

[0013]

[Chemical 2]

[0014]

[Chemical 3]

[0015]

[Chemical 4]

Etc., a copolymerizable photopolymerization initiator, benzoin,
Benzyl, benzoin methyl ether, benzoin isopropyl ether, acetophenone, 2,2-dimethoxy-2-phenylacetophenone, 2,2-diethoxy-2-phenylacetophenone, 1,1-dichloroacetophenone, 1-hydroxycyclohexylphenyl ketone, 2- Methyl-1- [4- (methylthio) phenyl) -2-morpholinopropan-1-one, N, N
-Dimethylaminoacetophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 2-tert-butylanthraquinone, 1-chloroanthraquinone, 2-amylanthraquinone, 2-aminoanthraquinone, 2,4
-Dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, acetophenone dimethyl ketal, benzophenone, methylbenzophenone, 4,4'-dichlorobenzophenone,
4,4'-bisdiethylaminobenzophenone, Michler's ketone and the like can be mentioned. These may be used alone or in combination of two or more. Further, such a photopolymerization initiator (D) is a known photosensitizer such as N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, triethanolamine and triethylamine. Alone or 2
A combination of two or more species can be used.

In the resin composition of the present invention, the component (D) is used in an amount of 0.5 to 10% by weight, preferably 1 to 7% by weight. Even if it is used in an amount of 10% by weight or more, the curability is not so much improved. Also, 0.5% by weight
In the following cases, the curability is not sufficient.

The resin composition of the present invention comprises (A), (B),
It can be obtained by dissolving and mixing the components (C) and (D). In addition to the above components, the resin composition of the present invention includes urethane (meth) acrylates (for example, ethylene glycol, 1,4-butanediol, neopentyl glycol, polycaprolactone polyol, polyester polyol, polycarbonate diol, polytetramethylene glycol, etc.). Polyols and hexamethylene diisocyanate, isophorone diisocyanate, tolylene diisocyanate, xylylene diisocyanate, 4,
Organic polyisocyanates such as 4'-diphenylmethane diisocyanate and 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate ε-
Examples thereof include reaction products of hydroxyl group-containing ethylenically unsaturated compounds such as a caprolactone adduct. ) Or a tri- or higher functional reactive monomer can be used if necessary. Further, a release agent, a defoaming agent, a leveling agent, a light stabilizer (for example, hindered amine, etc.), an antioxidant, a flame retardant, an ultraviolet absorber, a polymerization inhibitor, an antistatic agent and the like can be used in combination.

The cured product of the resin composition of the present invention can be obtained by irradiating the resin composition of the present invention with ultraviolet rays according to a conventional method. Specifically, the ultraviolet curable resin composition for a transmissive screen of the present invention is applied to, for example, a stamper having the shape of a Fresnel lens or a lenticular lens to form a layer of the ultraviolet curable resin composition, and the layer A transparent resin substrate is adhered onto the above, and in that state, the transparent resin substrate is irradiated with ultraviolet rays from a high pressure mercury lamp or the like to cure the resin composition, and then the resin composition is peeled off. In this way, the normal refractive index (23 ° C) is 1.55.
As described above, a transmission screen such as a Fresnel lens or a lenticular lens having 1.56 or more can be obtained under preferable conditions.

[0020]

EXAMPLES Next, the present invention will be described more specifically by way of examples. The evaluation in the examples was performed by the following methods. (1) Releasability: Difficulty in releasing the cured resin from the mold ○ ・ ・ ・ ・ Releasability from the mold is good △ ・ ・ ・ ・ Releasing is somewhat difficult × ・ ・ ・The mold is difficult or the mold is dull. (2) Mold reproducibility: The surface shape of the cured UV-curable resin layer and the surface shape of the mold were observed. ○ ・ ・ ・ ・ Reproducibility is good × ・ ・ ・ ・ Reproducibility is poor (3) Adhesion: 200 μm film thickness, 20 mm width, 150 m length of UV curable resin composition on transparent methacrylic substrate
m, then high pressure mercury lamp (80w / cm, ozoneless)
At 500 mj / cm ² , irradiation was carried out to cure and a test piece was prepared, and the peel strength was measured. (Measurement method of peeling strength: 90 degree peeling strength of the cured resin film on the methacrylic substrate was measured by a tensile tester. (Peeling speed 100 mm /
Minutes) ◎ ・ ・ ・ ・ Peeling strength 2kg / cm or more ○ ・ ・ ・ ・ Peeling strength 1-2kg / cm △ ・ ・ ・ ・ Peeling strength 0.5〜1kg / cm × ・ ・ ・ ・ Peeling strength 0.5kg / cm or less

(4) Restorability: After a metal round bar having a diameter of 10 mm is strongly pressed against the surface of the cured UV-curable resin layer released from the mold, until the mark of the round bar on the surface disappears completely. Was measured. ∘: Instantly disappeared ∙: Disappeared within 60 seconds △ ∙ Disappeared within 1 to 60 minutes × ∙ Not disappeared (5) Scratch resistance: cured While pressing the methacrylic resin plate (width 100 mm, length 100 mm, thickness 2.5 mm) vertically on the surface of the UV curable resin layer released from the mold, the interval of about 100 mm is reciprocated at a speed of about 1 second. 10
After reciprocating, scratches on the surface were observed. ◎ ・ ・ ・ ・ No scratches were observed ○ ・ ・ ・ ・ Striped scratches were observed △ ・ ・ ・ ・ Strip-shaped scratches were partially observed × ・ ・ ・ ・ Strip-shaped scratches were observed over the entire surface Permitted (6) Refractive index (25 ° C): Measure the refractive index (25 ° C) of the cured UV-curable resin layer

Examples 1 to 4 and Comparative Examples 1 to 4 An ultraviolet curable resin composition having the composition shown in Table 1 (numerical values indicate parts by weight) was used in a Fresnel lens mold and a thickness of 2.5 m.
m methacrylic resin substrate and then cured by irradiation with ultraviolet rays by a conventional method to obtain a Fresnel lens.

[0023]

[Table 1] Examples Comparative Examples 1 2 3 4 1 2 3 4 EP-1004AA * 1 20 30 40 20 30 20 KAYARAD R-114 * 2 40 Urethane acrylate * 3 10 30 KAYARAD R-128H * 4 20 20 20 10 10 10 20 KAYARAD R-561 * 5 10 15 15 10 KAYARAD R-564 * 6 10 20 10 20 KAYARAD OPP-2 * 7 20 10 10 30 20 20 FA-512A * 8 5 10 Tribromophenyl oxyethyl acrylate 10 10 10 10 10 10 10 KAYARAD R-551 * 9 10 10 20 BPE-10 * 10 20 15 5 15 10 20 20 Irgacure 184 * 11 3 3 3 3 3 3 3 3 LA-82 * 12 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 SH-3749 * 13 0.5 0.5 0.5 0.5 0.5 0.5 0.5 0.5 Physical properties of liquid Viscosity (25 ℃) CPS 3800 5630 7900 6210 6520 5120 6350 2100 Refractive index (25 ℃) 1,552 1,551 1,552 1,551 1,550 1,552 1,552 1,553 Cured product Physical properties Releasability ○ ○ ○ ○ ○ ○ ○ × Adhesion ◎ ○ ◎ ○ × × × ◎ Mold reproducibility ○ ○ ○ ○ ○ ○ ○ ○ Restorability ○ ◎ ○ ◎ ○ ◎ ◎ △ Scratch resistance ◎ ◎ ◎ ◎ △ × ◎ × Refractive index (25 ℃) 1 , 572 1,571 1,573 1,571 1,570 1,573 1,572 1,573

* 1 EP-1004AA: Bisphenol A type epoxy acrylate (Eikaka Shell Epoxy Co., Ltd., Epicoat 1004, epoxy equivalent 900) reacted with acrylic acid and bisphenol A type epoxy acrylate with a molecular weight of 1000 or more * 2 KAYARAD R-114: Nippon Kayaku Co., Ltd., bisphenol A type epoxy resin (Okaka Shell Epoxy Co., Ltd.)
Manufactured by Epicote 828, epoxy equivalent 180) epoxy acrylate * 3 Urethane acrylate: polyester diol Kuraray P-1010, molecular weight 1000) 1 mol and tolylene diisotheanate 2 mol 2.02 mol in the reaction product. -Urethane acrylate reacted with hydroxyethyl acrylate * 4 KAYARAD R-128H: Nippon Kayaku Co., Ltd., phenyl glycidyl ether acrylate * 5 KAYARAD R-561: Nippon Kayaku Co., Ltd., phenoxyethyl acrylate

* 6 KAYARAD R-564: Nippon Kayaku Co., Ltd.
Phenyl polyethoxy acrylate * 7 KAYARAD OPP-2: Nippon Kayaku Co., Ltd., o-phenylphenol polyethoxy acrylate * 8 FA-512A: Hitachi Chemical Co., Ltd., dicyclopentadiene aokiethyl acrylate * 9 KAYARAD R-551: Nippon Kayaku Co., Ltd., bisphenol A tetraethoxydiacrylate * 10 BPE-10: Bisphenol A polyethoxydiacrylate (average n is 10) * 11 Irgacure 184: Ciba Geigy, Photopolymerization initiator * 12 LA-82: Asahi Denka Co., Ltd., light stabilizer * 13 SH-3749: Shin-Etsu Silicone Co., Ltd., leveling agent

As is clear from Table 1, the cured product of the resin composition of the present invention shows releasability, mold reproducibility, adhesion, restoration property,
It had excellent scratch resistance and a high refractive index of 1.57 or higher.

[0027]

The cured product of the resin composition of the present invention has a high refractive index, excellent adhesion to a substrate, releasability, mold reproducibility,
It has excellent restorability and scratch resistance and is suitable for transmissive screens.

Claims (2)

[Claims] 1. Bisphenol A type epoxy (meth) acrylate (A) having a molecular weight of 1000 or more 20 to 50% by weight, monofunctional reactive monomer (B) 40 to 70% by weight, and bifunctional reactive monomer ( An ultraviolet-curable resin composition for a transmissive screen, which comprises C) 5 to 25% by weight and a photopolymerization initiator (D) 0.5 to 10% by weight. 2. A cured product of the resin composition according to claim 1.