JP2003342338A - Resin composition and optical element - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a resin composition having excellent optical properties such as a high refractive index, excellent in restorability, scratch resistance and adhesiveness to substrates, which can fulfill various properties when used as an optical member (lens) such as a screen for a projection television or the like and also to provide a cured product thereof. <P>SOLUTION: The resin composition comprises a urethane(meth)acrylate obtained by reacting a bisphenol A polyalkoxy-diol, an organic diisocyanate and a hydroxy-containing mono(meth)acrylate and a bisphenol A epoxy(meth) acrylate as oligomer components, a phenoxy polyethylene glycol(meth)acrylate and a bisphenol A polyethoxy-diol di(meth)acrylate as monomer components and a photopolymerization initiator, having ≥1.55 refractive index after resin curing. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photocurable resin composition for forming a lens, particularly a lens such as a Fresnel lens or a lenticular lens used in a projection television or the like, and a resin composition from the resin composition. Optical element.

[0002] Traditionally, the Fresnel lens, which have been produced by a press method, a casting method, or the like, require a long time in the making of the lens, were those poor productivity. In recent years, studies have been made to manufacture lenses using UV-curable resin fingers. Specifically, a mold having a lens shape is coated with an ultraviolet curable resin composition, the resin composition is sandwiched between a transparent resin substrate and the mold, and the resin is irradiated with ultraviolet rays from the substrate side. By curing the composition, it becomes possible to manufacture a lens in a short time. Furthermore, as projection televisions have become thinner and larger in recent years, various lens characteristics such as higher refractive index and mechanical characteristics have been required for resin for forming lenses, and various resin characteristics depending on the lens use environment. Suggestions and examinations have been made.

A Fresnel lens for a projection screen has a constitution in which a lens shape is formed on a plastic base material by using an ionizing radiation curable resin, and the base material is substantially optically anisotropic. It is said that a material with no transparency and excellent transparency is good. Conventionally, as its base material,
Polymethyl methacrylate (PMMA), a copolymer of methyl methacrylate and styrene (MS), polycarbonate (PC), a transparent olefin resin, etc. are used.

In order to impart impact resistance to a substrate on which a lens (cured product of ionizing radiation curable resin) is applied, butadiene rubber, acrylic rubber or the like is blended with the above resin to form a sea-island structure. Often transparent materials having are also used.

In these plastic substrates,
Depending on the application, performance and cost, it is very important which type of base material is selected, and depending on the base material used, it is possible to improve the adhesion of the ultraviolet curable resin to the base material. It has great significance from a practical point of view. For example, surface treatment (primer treatment, corona discharge treatment, flame treatment, ultraviolet treatment, plasma treatment, etc.) can be applied to the base material in order to improve the adhesion between the base material and the ultraviolet curable resin. Depending on the effect, there are differences. Moreover, in order to perform these surface treatments, a process and equipment are also required. Therefore, from the viewpoint of manufacturing cost, it is very effective that the lens material itself has good adhesion to the base material. For that purpose, it is important to select a resin composition having good adhesion to the substrate according to each substrate when selecting the substrate material, in order to shorten the lead time at the mass production level. Becomes

However, these UV-curable resins do not satisfy the performance required for the lens only by being excellent in the adhesion to the substrate. For example, a Fresnel lens not only has optical performance such as a refractive index, but also has a vibration damping property of suppressing rubbing due to contact with a lenticular lens, as disclosed in JP 2001-228549 A. In addition, rigidity or resilience that can withstand the contact pressure with the lenticular lens is required (see Patent Document 1).

That is, a projection screen is generally used in combination with a Fresnel lens and a lenticular lens, and in order to maximize the optical effect of the Fresnel lens and to protect the lens surface, the mutual lens is used. It is often practiced to bring the surfaces into close contact with each other. The Fresnel lens has a function of collimating the projected light to correct it in the vertical direction,
On the other hand, the lenticular lens has a function of diffusing the light collimated by the Fresnel lens in the horizontal direction. Usually, in such a projection screen, the light exit surface side of the Fresnel lens (circular Fresnel convex lens) and the light entrance surface side of the lenticular lens are used in close contact with each other.

As described above, when the lens surfaces of the optical element are brought into close contact with each other, both surfaces have irregularities, which influences the surface shape of each other. For example, in the above example, the cross section of the Fresnel lens surface has an uneven shape with a saw-toothed tip, while the cross section of the lenticular lens surface has a rounded shape such as a semicircle or a semi-ellipse. It has an arched concavo-convex shape. When the Fresnel lens sheet and the lenticular lens sheet having such a cross-sectional shape come into close contact with each other, the raised top of the lenticular lens and the sharp tip of the Fresnel lens come into contact with each other, and the contact pressure causes the lenticular lens and / or
Alternatively, the shape of the Fresnel lens, that is, the concavo-convex shape of the lens surface is deformed, and the lens is crushed.

In order to avoid this phenomenon, various measures have been taken such as adjusting the elastic modulus of the resin and sandwiching a slip agent or interleaving paper. Further, by kneading silicone into the Fresnel lens resin, the abrasion resistance is improved.

On the other hand, the above-mentioned deformation of the lens shape can be eliminated by increasing the hardness of the resin forming the lens. However, simply increasing the hardness causes the resin to become brittle, which causes a problem that the lens is likely to be chipped during handling or cutting. Therefore, the resin that constitutes the lens must have a certain degree of flexibility while having a high hardness.

The hardness of the resin cured product is generally related to the glass transition temperature. If the glass transition temperature is too low, the rubber elasticity will decrease and the resin will be plastically deformed by pressing. In general, a resin having a certain degree of cross-linking density exhibits rubber elasticity even when the glass transition temperature is low, and plastic deformation does not occur even when pressure is applied. However, in the resin composition for an optical element, in order to improve the refractive index as an essential requirement, it is necessary to introduce a rigid chain composed of a benzene ring or an alicyclic group into the molecular chain, so that the glass transition temperature Cause rise. Therefore, it is very difficult to lower the glass transition temperature to around room temperature while maintaining the desired refractive index. On the other hand, if the glass transition temperature is too high, it is advantageous in terms of improving the refractive index, but since the rigidity of the resin becomes high, internal stress (strain) tends to remain. Therefore, in the lens sheet having a structure in which it is bonded to the base material, the lens sheet is warped due to the relaxation of the lens resin.

On the other hand, when a material containing a halogen compound such as a bromine compound or sulfur is used, the refractive index can be increased without using an aromatic compound such as a benzene ring, and the physical properties of the material can be well controlled. It will be possible. However, from the viewpoint of environmental load, it is preferable to avoid the use of bromine as much as possible.

As described above, the lens formed by using the photocurable resin composition used in a projection television or the like has an optical performance such as a high refractive index, excellent restorability and scratch resistance, and The performance that the adhesion between the base material and the cured layer of the photocurable resin composition is good is required.

On the other hand, since it is necessary to release the resin cured product from the molding die when manufacturing the lens, it is required that the mold releasability between the molding die and the resin cured product is high.

However, under the present circumstances, it is not possible to satisfy all of these performances, and it is an object to provide a more excellent resin composition.

Therefore, the present invention is a resin composition having optical properties such as a high refractive index, excellent restorability, scratch resistance, and good adhesion to a substrate, and the resin composition. An object of the present invention is to provide a resin composition and a cured product thereof that can satisfy various performances when the composition is used as an optical member (lens) used for a screen of a projection television or the like.

Even when the optical member is molded by the 2P method, the quality characteristics of the optical member are not impaired.
An object of the present invention is to provide a resin composition in which the mold and the optical member can be easily released from each other.

[0018]

[Patent Document 1] Japanese Patent Laid-Open No. 2001-228549

[0019]

SUMMARY OF THE INVENTION To achieve the above object, the resin composition of the present invention comprises bisphenol A as an oligomer component.
Urethane (meth) acrylate obtained by reacting polyalkoxy diol, organic diisocyanate and hydroxyl group-containing mono (meth) acrylate, bisphenol A type epoxy (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate as a monomer component, and , Bisphenol A polyethoxydiol di (meth) acrylate, and a photopolymerization initiator, and the refractive index after resin curing is 1.55 or more. When a transmissive screen or the like is formed by using a cured product made of a resin having such a composition as a lens, it is possible to obtain a screen having sufficient front luminance, and also having optical performance such as a high refractive index, and a restoration. The optical member has excellent properties and scratch resistance, and also has good adhesion between the substrate and the cured product.

In a preferred embodiment of the present invention, the additive comprises polyether-modified polydimethylsiloxane.

In a more preferred embodiment, the resin composition of the present invention further comprises, as an internal mold release agent, a phosphoric acid ester represented by the following formula I or a phosphonic acid ester represented by the following formula II. It comprises.

[Chemical 3] (Here, n represents an integer of 4 or more.)

[Chemical 4] (Here, n represents an integer of 4 or more.) Furthermore, when the urethane chain concentration of the urethane oligomer contained in the resin composition is 0.5 to 1.3 mmol / g, The content is preferably 0.1 to 0.5% by weight with respect to the resin composition, and the urethane chain concentration of the urethane oligomer contained in the resin composition is 0.28 mmol / g or more. And the concentration of OH groups contained in the resin composition is 0.41 to
In the case of 1.2 mmol / g, the content of the release agent is preferably 0.1 to 1.0% by weight based on the resin composition. As described above, by using the above-mentioned phosphoric acid ester or phosphonic acid ester as the release agent, even when it is added to the resin composition in combination with the polyether-modified polydimethylsiloxane as the additive, the optical performance is improved. The mold releasability from the metal mold and the slipperiness can be imparted to the cured product without adversely affecting.

In a preferred embodiment of the present invention, the resin composition has a glass transition temperature of 19.5 ° C. to 23.7 ° C. and an equilibrium elastic modulus at 80 ° C. of 1.08 × 1.
0 ⁸ is ^{~1.57 × 10 8 dyne / cm 2} .

In the above resin composition, when the elastic deformation rate is represented by We (unit:%) and the compression elastic modulus (unit: MPa) is represented by E, We> -0.0189E + 34.2. It is more preferable that they are satisfied.

By using such a resin, it is possible to suppress the lens collapse due to the compression of the lens surfaces of the projection screen. That is, in the optical element using the resin composition of the present invention, the uneven portion of the lens surface is not crushed even when brought into close contact with a lenticular lens having a warp. In the region of We ≦ −0.0189E + 34.2, against the collapse due to the compression of the lens surfaces,
Poor restoration.

[0025]

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in more detail below. First, urethane (meth) acrylate (hereinafter referred to as component A), which is an oligomer component constituting the resin composition of the present invention, comprises bisphenol A polyalkoxy diol, organic diisocyanate, and hydroxyl group-containing mono (meth) acrylate. It is obtained by reacting. The resin composition in the present invention can improve the restorability of the resin after curing by containing the component A.

The content of the component A is based on the resin composition.
5 to 60% by weight is preferable, and 10 to 25 is preferable for holding.
% By weight.

Specific examples of the bisphenol A polyalkoxy diol include bisphenol A polyethoxy diol and bisphenol A polypropoxy diol.

Examples of organic diisocyanates include tolylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, hexamethylene diisocyanate, and trimethylhexamethylene diisocyanate. From the viewpoint of refractive index, aromatic diisocyanate such as tolylene diisocyanate or xylylene diisocyanate is preferable.

As the hydroxyl group-containing mono (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2
1-hydroxypropyl (meth) acrylate, 4-hydroxybutyl (meth) acrylate, polyethylene glycol mono (meth) acrylate, polypropylene glycol mono (meth) acrylate, and 2-hydroxy-3-phenoxypropyl (meth) acrylate Is mentioned. These hydroxyl group-containing mono (meth) acrylates may be used alone or in combination of two or more.

The urethane (meth) acrylate used in the resin composition of the present invention can be obtained by a known procedure. That is, a bisphenol A polyalkoxy diol component and an organic diisocyanate component are reacted by a urethanization reaction, and then a terminal isocyanate prepolymer obtained by the reaction is reacted with a hydroxyl group-containing mono (meth) acrylate component and a (meth) acrylate. It is obtained by a chemical reaction.

In the above urethane-forming reaction, 1 equivalent of hydroxyl group of the bisphenol A polyalkoxy diol component is equivalent to 1. 1 of isocyanate group of the organic diisocyanate component.
It is preferable to react 3 to 1.7 equivalents.

In the above (meth) acrylate reaction, the hydroxyl groups of the hydroxyl group-containing mono (meth) acrylate component are 0.9% with respect to 1 equivalent of the isocyanate group of the terminal isocyanate urethane prepolymer obtained by the urethane reaction. It is preferred to react ~ 1.1 equivalents. The above urethane reaction and (meth) acrylate reaction are carried out at room temperature to 100 ° C. The reaction usually proceeds without a catalyst, but a catalyst may be added, and dibutyltin dilaurate, dibutyltin diacetate or the like can be used as the catalyst.

Further, in this (meth) acrylate reaction, in order to prevent gelation due to radical polymerization during the reaction, hydroquinone, hydroquinone monomethyl ether, p
It is more preferable to add a polymerization inhibitor such as -methoxyphenol and p-benzoquinone.

The above reaction is preferably synthesized by taking a sufficient reaction time. Further, when the number average molecular weight of the component A becomes too large, the equilibrium elastic modulus (crosslink density) at 80 ° C. becomes low. Therefore, when an external force is applied to the resin cured product, the external force directly affects the viscous segment. Become. As a result, the resin cured product is easily plastically deformed. On the other hand, when the number average molecular weight of the component A is too small, the molecular chain between the cross-linking points becomes rigid, and it becomes difficult to obtain the resilience of the cured resin.

That is, in the present invention, at 80 ° C.
Equilibrium elastic modulus is 1.08 × 10 ⁸~ 1.57 × 10⁸
dyne / cm^TwoUse a resin composition in the range of
Balances the degree of plastic deformation with the resilience.
In addition, it is possible to obtain an optical element with excellent restoration and scratch resistance.
I found that I could do it. With the above equilibrium modulus
In the resin composition to be used,
(Meth) acrylate component has an average molecular weight of 2000 to
It is preferably 8000, and particularly 4000 to 600
0 is preferred. The average molecular weight used in this specification and
Means the number average molecular weight unless otherwise specified.

The above bisphenol A polyalkoxydiol is represented by the following general formula (III).

[Chemical 5] Where m and n are integers and R ₁ and R ₂ are either H or CH ₃ , respectively.

The bisphenol A type epoxy (meth) acrylate (hereinafter,
Ingredient B. ) Is a component necessary for setting the refractive index of a cured product of the resin to 1.55 or more. The component B
The content of is preferably 5 to 50% by weight, and particularly preferably 5 to 20% by weight, based on the resin composition. In addition,
The refractive index used in the present specification, unless otherwise specified,
It means a value at 25 ° C.

The above bisphenol A type epoxy (meta)
Acrylate is represented by the following general formula (IV).

[Chemical 6] Here, o is an integer and is larger than 1. Also, R ₃
And R ₄ are each H or CH ₃ . When o is less than 1, the cured product of the resin composition becomes too hard and the restorability is reduced. Further, the refractive index becomes lower than 1.55, which is not preferable. In addition, this bisphenol A
The type epoxy (meth) acrylate can be produced by a known method. That is, with respect to 1 equivalent of the epoxy group of the bisphenol A type epoxy compound, 0.9 to
By reacting 1.1 equivalents of (meth) acrylic acid in the presence of a catalyst such as a tertiary amino compound such as dimethylaminoethyl methacrylate, a mixture with a quaternary amine, and a mixture with a quaternary amine salt, bisphenol is obtained. A type epoxy (meth) acrylate can be manufactured. The reaction temperature is 50 ° C to 120 ° C.

The phenoxy polyethylene glycol (meth) acrylate (hereinafter, referred to as the following) constituting the resin composition of the present invention
It is called component C. ) Is a component necessary for maintaining the refractive index of the resin cured product at 1.55 or more and improving the adhesion to the substrate. The content of the component C is preferably 10 to 60% by weight with respect to the resin composition, and particularly preferably 1
It is 0 to 35% by weight.

Usually, the monofunctional monomer is used for adjusting the viscosity and improving the adhesion to the substrate, but a structure composed of an aliphatic hydrocarbon or an alicyclic hydrocarbon cannot provide a sufficient refractive index. . In the resin composition of the present invention, since a phenoxy polyethylene glycol (meth) acrylate having a structure containing an aromatic ring such as a phenoxy group is used as a constituent component, it is possible to satisfy not only the adhesion but also a desired refractive index. .

Phenoxypolyethylene glycol (meth) acrylate is represented by the following general formula (V).

[Chemical 7] Here, p is an integer and is 1 to 4. R ₅ is H or CH ₃ . When p is larger than 4, the refractive index is lowered and the adhesion to the substrate is lowered.

As the above component C, Aronix M-1 is used.
01, M-102 (all manufactured by Toagosei Co., Ltd.), NK ester M-20G, M-40G, AMP-10G, AMP
-20G (above, Shin Nakamura Chemical Co., Ltd.), KAYAR
AD R-561, R-564 (Nippon Kayaku Co., Ltd.)
Made), light ester PO, light acrylate PO-
A, P-200A (above, Kyoeisha Chemical Co., Ltd.), Viscoat # 192, # 193 (above, Osaka Organic Chemical Industry Co., Ltd.), and New Frontier PHE, PH
Commercial products such as E-2 (all manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) can be used.

The bisphenol A polyethoxydiol di (meth) acrylate (hereinafter referred to as the component D) constituting the resin composition of the present invention has a high refractive index and improves the restoration of the cured resin. It is a necessary ingredient. The content of the component D is 15 to 15 with respect to the resin composition.
It is preferably 75% by weight, particularly preferably 30 to 50% by weight.

The bisphenol A polyethoxydiol di (meth) acrylate is represented by the following general formula (VI).

[Chemical 8] Here, q and r are integers, and the value of q + r is 6 to 1.
It is 4. In addition, R ₆ and R ₇ are each H or CH ₃ . When the value of q + r is less than 6, the hardness of the resin cured product increases and the restorability decreases. On the other hand, when the value of q + r exceeds 14, the refractive index becomes smaller than 1.55, which is not preferable.

As component D, NK ester BPE-5
00, NK ester A-BPE-10 (above, Shin-Nakamura Chemical Co., Ltd.), SR-480, SR-602 (above, S
(Made by ARTOMER), Light acrylate BP-10
Commercially available products such as EA (all manufactured by Kyoeisho Chemical Co., Ltd.), New Frontier BPE-10, and BPEM-10 (all manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) can be used.

In the resin composition of the present invention, a compound (monomer component) containing a (meth) acryloyl group or vinyl group other than the above-mentioned components C and D can be used as an optional component.

Examples of such a monomer component include, as monofunctional monomers, vinyl monomers such as N-vinylpyrrolidone, N-vinylcaprolactone, vinylimidazole, vinylpyridine and styrene, and lauryl (meth).
Acrylate, stearyl (meth) acrylate, butoxyethyl (meth) acrylate, ethoxydiethylene glycol (meth) acrylate, methoxytriethylene glycol (meth) acrylate, methoxypolyethylene glycol (meth) acrylate, methoxydipropylene glycol (meth) acrylate, varakumil Phenoxyethyl (meth) acrylate, nonylphenoxypolyethylene glycol (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, benzyl methacrylate, N, N-dimethyl (meth) acrylamide, (Meth) acryl such as N, N-dimethylaminopropyl (meth) acrylate and acryloylmorpholine Acid ester monomer, and (meth) acrylamide derivatives.

As the polyfunctional monomer component, ethylene glycol di (meth) acrylate, diethylene glycol di (meth) acrylate, triethylene glycol di (meth) acrylate, polyethylene glycol di (meth) acrylate, tripropylene glycol di (meth) acrylate. , Polytetramethylene glycol di (meth) acrylate, 1,4-butanediol di (meth) acrylate, 1,6-hexanediol di (meth) acrylate, 1,9-nonanediol di (meth)
Acrylate, 3-methyl-1,5-pentanediol di (meth) acrylate, neopentyl glycol di (meth) acrylate, dimethylol-tricyclodecane di (meth) acrylate, hydroxypivalic acid neoventil glycol di (meth) ) Acrylate, bisphenol A polypropoxydiol di (meth) acrylate, trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolbroban tri (meth) acrylate, pentaerythritol tri (meth) acrylate ) Acrylate, glyceryl tri (meth) acrylate, propoxylated glyceryl tri (meth) acrylate, tris (2-hydroxyethyl) isocyanurate triacrylate, penta Examples thereof include erythritol tetra (meth) acrylate, ditrimethylolpropane tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, and dipentaerythritol hexa (meth) acrylate.

The content of the photopolymerization initiator constituting the resin composition of the present invention (hereinafter referred to as component E) is preferably 0.1 to 15% by weight, based on the entire resin composition. 0.1
If it is less than 10% by weight, sufficient photocurability cannot be obtained.
If it exceeds 5% by weight, it does not contribute to the photo-curing of the resin composition and is wasted, resulting in an increase in cost.

Examples of the component E include 1-hydroxycyclohexyl phenyl ketone and 2-hydroxy-2.
-Methyl 1-phenylpropan-1-one, 2,2-dimethoxy-1,2-diphenylethan-1-one, 2-
Benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4-
(Methylthio) phenyl] -2morpholinopropane-
Examples include 1,2,4,6-trimethylbenzoyldiphenylphosphine oxide, phenylbis (2,4,6-trimethylbenzoyl) -phosphine oxide, and the like.

The resin composition of the present invention contains the above components A to
In addition to E, the following are preferably included. That is, the resin composition may contain silicone, a silicone polymer, preferably a modified silicone, more preferably a polyether-modified polydimethylsiloxane additive. By containing such an additive, slipperiness is improved, and when the resin composition is cured to form a lens sheet, it is possible to reduce the occurrence of scratches on the lens surface due to rubbing between the lens sheets. .

The content of the above additives with respect to the entire resin composition is preferably 0.01 to 10% by weight. If it is less than 0.01% by weight, the desired slipperiness cannot be obtained, while if it exceeds 10% by weight, the physical properties of the resin composition are impaired or the adhesion between the base material and the cured resin is deteriorated. To do.

Specific examples of the above silicone and silicone polymer include B manufactured by Big Chemie Japan Co., Ltd.
YK-307, BYK-333, BYK-332, BY
K-331, BYK-345, BYK-348, BYK
-370, BYK-ichi UV3510, Shin-Etsu Chemical Co., Ltd.
X-22-2404, KF-62-7192, KF-
615A, KF-618, KF-353, KF-353
A, KF-96, KF-54, KF-56, KF-41
0, KF-412, HIVACF-4, HIVACF-
5, KF-945A, KF-354, and KF-35.
3. SH-2 manufactured by Toray Dow Corning Japan KK
8PA, SH-29PA, SH-190, SH-51
0, SH-550, SH-8410, SH-8421,
SYLGARD309, BY16-152, BY16-1
52B and BY16-152C, FZ-2105, FZ-2165, FZ-216 manufactured by Nippon Unicar Co., Ltd.
3, L-77, L-7001, L-7002, L-760
4, and L-7607, EFKA-S018, EFKA-3033, and EFKA-8 manufactured by Efka Adityps
3, EFKA-3232, EFKA-3236, and E
Examples include FKA-3239, Granol 410 manufactured by Kyoeisha Chemical Co., Ltd., and the like.

Further, in order to prevent the silicone component from bleeding out with time due to changes in the environment after the resin is cured, a reactive silicone such as silicone acrylate or silicone methacrylate may be supplementarily used. Specific examples of the reactive silicone include BYK-UV35 manufactured by Big Chemie Japan Co., Ltd.
00, BYK-UV3530, Dow Corning Pentad UV-31, and Shin-Etsu Chemical Co., Ltd. X-24-8201, X-22-174DX, X.
-22-2426, X-22-2404, X-22-164
A, X-22-164B, X-22-164C, and the like.

In the resin composition of the present invention,
It is preferable to comprise a release agent represented by the following formula VII or VIII.

[0056]

[Chemical 9] (Here, n represents an integer of 4 or more.)

[Chemical 10] (Here, n represents an integer of 4 or more.)

The resin composition of the present invention is applied to the surface of a mold,
When a lens sheet is produced by curing the resin composition with ultraviolet rays, it is necessary to peel the cured product from the mold.
However, since the resin composition of the present invention contains a polar group such as a hydroxyl group or a polar chain such as a urethane chain,
The adhesiveness between the resin composition and the metal mold is strong, and it becomes difficult to peel the cured product from the mold. Even when the above-mentioned silicone-based additive is contained in the resin composition, in particular, in the Fresnel lens, since the lens surface has a complicated shape, the resin is applied to the imprinted portion of the mold surface. Becomes difficult to separate from the mold and the lens (cured product). As described above, when the amount of silicone added is increased, the releasability is improved, but the physical properties of the material of the lens are lowered and the adhesion to the base material is lowered.

For such a problem, Japanese Patent Publication No. 6-207
52, JP-A-3-287641, and JP-A-11-43493 disclose alkoxyalkyl phosphates as a mold release agent for lenses, and JP-A-8-57864. Discloses an acidic phosphonic acid derivative-based internal release agent.

However, as described above, when the resin composition contains the polyether-modified polydimethylsiloxane as a slip agent, it is necessary to consider the compatibility between the polyether-modified polydimethylsiloxane and the release agent. is there. That is, even when the content of the release agent and the slip agent in the resin composition is low, both the silicone component and the phosphate ester component bleed out to the mold interface, and the silicone component and the The concentration of the release agent locally increases. When the compatibility between the silicone and the release agent is low, the resin composition has a cloud point (liquid state), or even if the resin composition is transparent in the liquid state, clouding occurs on the surface of the molded product after the resin is cured. There is. Further, when the compatibility between the release agent component and the silicone component is low, only the release property is expressed,
Sliding property or transparency of molded product is not improved, or conversely, even if sliding property is improved, mold release property is not sufficient and appearance changes with time (silicone component bleeding). .

In the present invention, as the internal mold releasing agent, a phosphoric acid ester having the structure of the above formula VII or a formula VII is used.
By using the phosphonate ester having the structure of I, it is possible to provide a resin composition that maintains the transparency of the cured product even when it is cured and is excellent in releasability. That is, since it has sufficient compatibility with the polyether-modified polydimethylsiloxane that is an additive necessary for imparting slipperiness, the release agent and the additive bleed out on the surface of the cured product after the resin is cured. However, the surface of the cured product (molded product) does not fog.

Further, the lens sheet formed by curing the resin compound containing the releasing agent having the structure represented by the above formula VII or VIII in the present invention is molded even when stored in a high temperature and high humidity environment for a long time. Does not change and is excellent in stability over time.

The releasing agent in the present invention has one OH group, that is, has a phosphodiester or phosphonic acid monoester structure. Phosphoric acid triesters having no OH group have high compatibility with polyether-modified polydimethylsiloxane, but have insufficient mold releasability. On the other hand, the phosphoric acid monoester having two OH groups is excellent from the viewpoint of transparency and slipperiness of the resin cured product (lens sheet), but has low compatibility with the polyether-modified polydimethylsiloxane, and the above-mentioned release Type issues arise.

In the phosphoric acid ester and phosphonic acid ester as the release agent in the present invention, the ester portion has 4 or more carbon atoms. If the carbon number is small, sufficient releasability cannot be obtained. Preferably, the carbon number is 8 or more.

In a preferred embodiment, the content of the releasing agent in the present invention is preferably 0.05 to 5.0% by weight, more preferably 0.1 to 1.0% by weight, based on the resin composition. is there. If it is less than 0.05% by weight, the releasability is not sufficient, while if it exceeds 5.0% by weight, the physical properties of the material of the molded product are impaired.

When the urethane chain concentration of the compound contained in the resin composition is 0.5 to 1.3 mmol / g in the urethane chain concentration of the urethane oligomer, the content of the releasing agent is the resin composition. 0.1 to 0.5 for things
Preferably, the urethane chain concentration of the urethane oligomer contained in the resin composition is 0.1% by weight.
When the concentration of the OH group contained in the resin composition is 28 mmol / g or more and 0.41 to 1.2 mmol / g, the content of the release agent is 0 with respect to the resin composition. It is preferably 0.1 to 1.0% by weight. The OH group concentration means the bisphenol A type epoxy acrylate oligomer, hydroxyethyl (meth) acrylate, hydroxypropyl (meth) acrylate, and 2-hydroxy-, among the above-mentioned compounds constituting the composition.
The ratio of the OH group in the hydroxy monomer such as 3-phenoxypropyl (meth) acrylate to the entire resin composition is shown. The urethane chain concentration refers to the proportion of urethane bonds contained in the urethane (meth) acrylate oligomer constituting the resin composition of the present invention in the entire resin composition.

In the resin composition of the present invention, hydroxyl groups and urethane chains (general materials including urethane chains such as urethane acrylate oligomers) are contained in the resin composition as factors that inhibit the releasability from the metal mold. Is included. Even when the concentration of the urethane chain is lower than 0.5 mmol / g, a mold releasing agent may be contained from the viewpoint of mold releasability from the mold. However, practically, within a range that does not impair the material properties of the molded product, that is,
Less than 0.2% by weight, preferably 0.05-0.2% by weight
A release agent may be contained within a certain range.
In the case of resin molding that does not use a metal mold, a release agent may not be included. That is, even if the difference in surface energy between the resin used for the non-metal mold and the resin to be applied is large, or even if the difference in surface energy is small, a fluorine-based additive or a silicone additive is used. Or a material having a fluorine atom or a silicon atom can be used as the resin composition.

The urethane chain concentration of the urethane oligomer is
When it is 1.3 mmol / g or more, the adhesiveness with a metal increases, the molded product does not peel from the mold, and even if it peels at the initial stage of molding, if several to several tens are molded, the resin becomes a mold. Starting to remain, the releasability is further reduced due to the residual resin.
In the present invention, by containing 0.1 to 0.5% by weight of the release agent represented by the above formula VII or formula VIII with respect to the resin composition, the problem of releasability can be solved. it can. When the content of the release agent is less than 0.1% by weight,
The releasability is not improved, while if it exceeds 0.5% by weight,
The presence of phosphoric acid or the like causes the ester structure of the polyester urethane polymer or the like to be hydrolyzed, resulting in a decrease in the viscosity due to a decrease in the molecular weight, which deteriorates the moldability of the resin.

When a non-metallic resin mold is used as the lens mold, it is not necessary to contain a phosphate ester-based mold release agent, but the resin mold contains fine metal particles, metal elements, or the like. In this case, like the metal mold, it is preferable that the mold release agent is contained. Even when a non-metal mold is used, good mold release is achieved by minimizing the surface energy of either the mold or the resin composition and increasing the surface energy difference between the two. Sex can be expressed. That is, depending on the relationship of the surface energy with the lens molding resin composition, a silicon-based lubricant or a fluorine-based additive is added to the resin composition, or a silicone or a fluorine-based additive is blended with the resin composition. By using it, the releasability from the molding die can be improved.

From the viewpoint of the refractive index, it is preferable to introduce an aromatic compound rather than using an alkyl chain in the ester portion because the refractive index is higher. However, when the aromatic compound is introduced, the freezing point temperature of the phosphoric acid ester and the phosphonic acid ester itself rises, so that the storage stability of the resin composition liquid at low temperature and the stability of the molded product when stored at low temperature are considered. Is not preferable. Also, depending on the degree of compatibility with the polyether-modified polydimethylsiloxane, when the release agent and the polyether-modified polydimethylsiloxane are compatible with each other to some extent, the silicone component may also be present when the release agent solidifies. Since it solidifies, the slipperiness in a low temperature environment is impaired. The freezing point temperature of the phosphoric acid ester and phosphonic acid ester in the present invention is preferably −50 ° C. or lower, more preferably −30 ° C. or lower, though it depends on the environment in which it is used.

The resin composition of the present invention may contain a plasticizer, a leveling agent, a defoaming agent, a thermal polymerization inhibitor, an antioxidant, a light stabilizer, a solvent and the like, if necessary.

The resin composition of the present invention comprises the above components A to E.
And, if necessary, by mixing and dissolving with other components, it can be usually obtained as a liquid composition. The viscosity of the liquid composition is 500 to 10,000 cps (25
C.) is preferable.

The optical element of the present invention can be obtained according to a conventional method. That is, the liquid resin composition has no concentration gradient and is uniformly emulsified, and in a state where each component is uniformly dispersed, the liquid resin composition is irradiated with ultraviolet rays to cure the resin composition. Thereby, an optical element can be obtained. By uniformly dispersing each component, the optical element has a high refractive index. For example, the refractive index is preferably 1.55 or higher (25 ° C.), and a lens having a high refractive index optical performance can be produced by using the optical element.
The optical element using the resin composition of the present invention is one in which each component is cured in a uniformly dispersed state, and the light transmittance is not less than a certain level, and it is always required to have high transparency. Instead, it may have light diffusing properties.

The optical element of the present invention comprises a transparent resin substrate on which a cured material layer made of the resin composition of the present invention is formed in a lens shape. The thickness of the cured product layer is 10 to 300.
About μm is preferable. Examples of the transparent resin base material include polycarbonate resin, polystyrene resin, polyester resin, polyacrylic resin, and a mixed resin thereof. As a means for improving the adhesiveness (adhesiveness) between the transparent resin substrate and the cured product layer of the resin composition, it is roughly classified into cleaning treatment, polishing treatment, chemical treatment 1 (oxidizing the substrate surface, 5 treatments of etching to improve the affinity with the composition), active gas treatment, chemical treatment 2 (treatment of applying a compound having an affinity for both the adhesive and the adherend; primer treatment) There is. Of these treatments, the cleaning treatment, the polishing treatment, and the chemical treatment 1 attack the base material itself and may affect the material properties of the base material itself. Have difficulty.

When used as a member for an optical element, active gas treatment and chemical treatment 2 may be mentioned, but the active gas treatment is low in versatility because there is a difference in treatment ability depending on the types of adhesive and adherend. In addition, the effect may be lost unless the adhesive is applied immediately after the treatment, which may limit the manufacturing process. Further, the chemical treatment 2 cannot be applied to any manufacturing method because it has problems in handling such as increase in manufacturing cost and dust adhesion. Further, although the chemical treatment 2 has an adhesive effect, it is complicated in terms of production to select a compound having an affinity for both the type of the base material and the resin composition such as an ultraviolet curable type, and solves these problems. Is difficult.

In the resin composition of the present invention, the resin composition is applied directly onto the substrate without the above-mentioned special treatment and is cured to form a cured layer. Adhesion between the substrate and the layer of the cured product becomes good. The resin composition of the present invention is a polystyrene resin-based substrate having moisture absorption resistance (specifically, for example, SX10 manufactured by Asahi Kasei Corporation).
0, TH21 manufactured by Denki Kagaku, Clearpact T1300 manufactured by Dainippon Ink and Chemicals, Estyrene MS-600 manufactured by Nippon Steel Chemical Co., Ltd., PMMA (polymethylmethacrylate) resin base material, PC (polycarbonate) )
Excellent adhesion to various substrates such as resin substrates.

The method for producing a lens-shaped molded article in the present invention is, for example, a method in which a resin composition of the present invention is applied to a mold having a Fresnel lens shape to form a coating film, and a transparent resin is formed on the coating film. After providing a base material, and then in this state, the transparent resin base material side is irradiated with ionizing radiation such as ultraviolet rays by a high pressure mercury lamp or the like to cure the resin composition, and then the base material is cured from the molding die. It peels off from the object. In this way, a Fresnel lens or the like made of the cured product, which usually has a refractive index of 1.55 or more (25 ° C.), can be obtained.

The resin composition of the present invention is an ionizing radiation curable resin composition having photocurability. As the ionizing radiation, visible rays, ultraviolet rays, electromagnetic waves such as X-rays, or charged particle beams such as electron rays are used. Among these, visible rays, ultraviolet rays, or electron rays are preferably used in practice. To be In particular, when using visible light or ultraviolet light, it is necessary to use a photopolymerization initiator that dissociates and generates radicals by ultraviolet light or visible light having a wavelength of 1000 to 8000Å.

When the cured product of the resin composition of the present invention is used as a member for an optical element, compression elastic modulus, creep deformation ratio and crush resistance, rubbing resistance at low temperature, storage elastic modulus,
Material properties such as loss tangent and dynamic friction coefficient are important indicators. Projection screens that are composed of two types of lenses, lenticular lenses and Fresnel lenses, are currently the mainstream. This pair of lenses is configured such that the curved (arched) lens on the light-incident surface side of the lenticular lens and the triangular (wedge-shaped) lens of the Fresnel lens are in contact with each other. Pressure is applied, and deformation of the shape of the lens tip is particularly likely to occur. It is considered that such contact pressure occurs due to the following reasons. Ie 2
Since the separation of one lens adversely affects the image, the lenticular lens is provided with a warp shape so that the two lenses are not separated. Since the projection screen is manufactured by pressing the lenticular lens having the warp against the Fresnel lens which is a pair thereof, pressure is naturally generated at the contact portion between both lenses. Therefore, the resin forming the Fresnel lens must have material physical properties that can withstand the pressure.

For that purpose, it is necessary to consider not only the hardness but also the opposing force (creep property) against the pressure applied for a long time between both lenses. The resin can be evaluated by the compression elastic modulus and the creep deformation rate measured using a micro hardness meter.

One of the two lens sheets has a Fresnel lens whose surface has a continuous wedge shape, and the other lenticular lens has a continuous arched surface. Have Therefore, when both lenses are overlapped, the wedge-shaped portion and the arch-shaped portion contact each other. When transporting the above two types of lenses in combination, due to vibration during transport,
Since both lenses with different rigidity behave differently, the tip of the Fresnel lens (the tip of the wedge) may be deformed or destroyed by rubbing or impact, or the lens surface may be scraped and white powder may be generated. To do.

Further, in the above Fresnel lens, since the resin forming the lens portion is usually made of a resin having a high elastic modulus, it is necessary to have abrasion resistance against temperature change. A resin material for a screen having various physical properties such that the lens does not deform even under various screen use environments, that is, at a high temperature, and does not rub at a low temperature (0 ° C.) or an extremely low temperature (−20 ° C.). desired.

In the dynamic viscoelasticity test, the storage elastic modulus (hardness) is not more than a predetermined value, and it is necessary to attenuate the amplitude amount in the resonance frequency range. In other words, the larger the loss tangent (tan δ) that is an index for converting the vibration energy into the heat energy, the more the vibration is suppressed and the friction is reduced.
In addition, it is necessary to give the slip performance effective for the shift.

[0083]

[Example] Polymethylmethacrylate resin (PMM
A), a polycarbonate resin (PC), and a rubber-modified styrene resin (MBS resin) containing a rubber-like elastic material as dispersed particles in order to impart impact resistance to the styrene resin having moisture absorption resistance. Resin was used as a substrate. Below, the blending ratio of the resin composition, the viscosity of each resin composition, the adhesion between the substrate and the resin composition, the optical characteristics of the resin composition (refractive index, haze value and total light transmittance), And material properties (compressive elastic modulus, elastic deformation rate,
The glass transition temperature, equilibrium elastic modulus, and dynamic friction coefficient) are shown in Table 1 below. Table 1 also shows the evaluation results (TV set crushing test and rubbing resistance test) of optical elements using each resin composition. Composition B, composition C, composition F, composition G and composition H are examples, and composition A, composition D, composition E and composition J are reference examples.

[0084]

[Table 1]

The above evaluations and measurement results are based on the following methods. Ink viscosity The viscosity of the resin composition was measured based on the rotational viscometer method of JIS K-5400. BL-type viscometer manufactured by Tokyo Keiki Co., Ltd. 3 rotors, 40 rpm, 12 rpm, 1
The viscometer reading after the minute was measured. The value obtained by multiplying the measured viscometer indicated value by a conversion multiplier (100 under the present conditions) was taken as the viscosity.

As the refractive index sample, a cured sheet prepared in the same manner as the sample for dynamic viscoelasticity measurement shown below was used, and the sample was prepared by using 1-bromonaphthalene in the prism portion of the Abbe refractometer. Adhesion was made, the sample temperature was set to 25 ° C, and the D line (λ = 58
The refractive index at 9 nm) was measured. (Others are JIS K
7105)

Haze value and total light transmittance Based on JIS K7150, a diffuse transmittance T _d and a total light transmittance T were measured using an integrating sphere type light transmittance measuring device.
_i was measured and a haze value of 100 parts per ratio of _{T d} for _{T i.}

Adhesion with Substrate The adhesion between the substrate and the resin composition was evaluated as follows. Each resin composition shown in Table 1 was applied to the surface of a Fresnel lens forming mold by a predetermined method, and MBS was applied on the coating film.
A resin substrate was provided, the resin composition was sandwiched between the mold and the substrate, and the substrate was pressed so that the coating film thickness was constant. Next, ultraviolet rays are irradiated from the side of the substrate to cure the resin composition to form a cured layer, and then the cured layer and the substrate (these are sheet lenses) are separated from the mold. Then, a sheet lens was obtained. (Incidentally, although not described in each composition of Table 1, the photoinitiator was added in the same amount and cured under the same conditions.) The resin composition (from the release surface side of the obtained sheet-shaped lens) In order to evaluate the adhesiveness between the cured layer) and the MBS resin base material, a cross-cut peeling test based on JIS K5400 was performed. The evaluation was performed by calculating the ratio of the number of bonded (X) and the value of X / 100 with respect to 100 grids (size of 1 mm × 1 mm).

[0089]Preparation of samples for dynamic viscoelasticity measurement For measuring storage modulus and dynamic viscoelasticity of equilibrium modulus
The sample was prepared as follows. 40-42
Mold of stainless steel plate with flat surface whose temperature is controlled to ℃
And each resin composition adjusted to 40 to 42 ° C. on the mold surface
Was applied to have a thickness of 200 μm. Metal hara
Id type UV lamp (manufactured by Nippon Battery Co., Ltd.)
Total light amount 2000mJ / cm^Two, Peak illuminance 250
mW / cm ^TwoThe resin composition is hardened by irradiation under the conditions
After curing, remove the cured sheet and
Got

[0090] Preparation of Sample for Measurement of adjusting the compression modulus of compressive elasticity modulus measurement sample, the surface instead of a flat stainless steel plate, using a nickel mold having a reverse shape of the Fresnel lens on the surface Other than the above, the sample sheet having the shape of the Fresnel lens was obtained in the same manner as in the adjustment of the sample for measuring dynamic viscoelasticity.

Measurement of Dynamic Viscoelasticity The obtained sample was molded into a strip of 30 mm × 3 mm × 0.2 mm, and a dynamic viscoelasticity measuring device (manufactured by Orientec Co., Ltd., “Reo Vibron”) was used. 0.05% for sample
The storage strain and loss tangent were measured by applying a load strain of. The frequency is 1 to 10 Hz, and the temperature range is
The temperature was set to −100 to 100 ° C. (heating rate of 3 ° C./min). By this measurement, the temperature dependence curve of the storage elastic modulus,
And the temperature dependence curve of loss tangent was obtained. From the temperature dependence curve of the obtained storage modulus, 25 ° C (normal temperature), 0 ° C,
And the storage elastic modulus at each temperature of −20 ° C. was obtained.
Separately from this, the frequency of forced vibration was set to 1 Hz, and the storage elastic modulus at 80 ° C. was determined from the temperature dependence curve of the storage elastic modulus obtained in the same manner as above, and the obtained value was taken as the equilibrium elastic modulus. In addition, from the obtained temperature dependence curve of loss tangent, 2
The loss tangent at each temperature of 5 ° C (normal temperature), 0 ° C, and -20 ° C was obtained. The glass transition temperature is the loss tangent (tan
It was the temperature at the peak position of 1 Hz of δ).

Measurement of dynamic friction coefficient A sample was obtained in the same manner as the above-mentioned sample for measuring dynamic viscoelasticity except that the thickness was 100 μm, the sample was covered with an acrylic plate and irradiated with ultraviolet rays. For the measurement, a surface measuring device (Shinto Kagaku Co., Ltd., Haydon Trypogear type: 14D
R) was used. A vertical load is applied to the obtained sample surface with a ball indenter (point pressure of 100 g), and the ball indenter is set to 300 m
The coefficient of dynamic friction was measured by sliding the surface of the sample at a speed of m / min. This measurement was performed 5 times, and the average value was used as the value of the dynamic friction coefficient.

Measurement of compression modulus Ultra micro hardness tester (H-100V, manufactured by Fischer GmbH, Germany)
By applying the universal hardness test using
The compression modulus was calculated. That is, the load by the indenter is gradually increased to a predetermined value and then gradually decreased to obtain a load dependence curve of the penetration depth, and the compression elastic modulus is calculated by analyzing the measurement result. did. A ball indenter made of tungsten carbide (WC) having a diameter of 0.4 mm was used as the indenter. The load dependence curve of the penetration depth typically shows the aspect as shown in FIG. First, when the load f is gradually increased from 0 (point a), deformation occurs, and the indenter penetration depth gradually increases. If the increase in load is stopped at a certain load value, the intrusion due to plastic deformation stops (point b), and if the load value is maintained as it is thereafter, the depth of penetration continues to increase due to creep deformation and the load value is maintained. To point c where you stop. After that, when the load is gradually reduced, the penetration depth decreases toward the point d due to elastic deformation.

In the above, the maximum load value F, which is the load value at point b in FIG. 1, was set to 20 mN. The reason is as follows. With an actual projection screen, it is difficult to measure the contact pressure between the Fresnel lens sheet and the lenticular lens sheet. However, if the deformation of the lens forming the screen is about 10 μm at the outer peripheral portion of the lens sheet under strict conditions, it is acceptable in terms of lens performance. Therefore, the load required to deform the conventionally used lens sheet by 10 μm is about 20 mN, so the maximum load value is set to 20 mN. Further, the time for causing the cleave deformation was appropriately 60 seconds.

The procedure for obtaining the load dependence curve of the penetration depth is shown below. (1) Increase the load value for compression from 0 to 20 mN in 100 steps every 0.1 seconds. (2) A load value of 20 mN is maintained for 60 seconds to cause creep deformation. (3) Decrease in 40 steps every 0.1 seconds until the load value reaches 0.4 mN (test machine minimum load). (4) Maintain the load value of 0.4 mN for 60 seconds to recover the penetration depth. (5) The above operations (1) to (4) are repeated three times. It should be noted that, as the portion on which the ball indenter acts, as shown in FIG. 2, individual subdivided lens surfaces constituting the Fresnel lens, for example, 2c, 2c ′, and 2 in FIG.
It is preferable to be near the central portion of the portion indicated by c ″. If the pitch between the adjacent concave portions of the lens surface is P, it is near the position corresponding to P / 2. Also in this case, it is preferable to act the ball indenter near the center of each lens surface forming the lens.

The compression elastic modulus (E) was determined by the following formula. E = 1 / (2 (hr (2R-hr)) ^1/2 × H × (ΔH / Δ
f)-(1-n) / e) Here, hr is the tangent line of the load dependence curve of the penetration depth and the penetration depth axis (horizontal axis) in the load reduction area when the load f is the maximum value F. ) Is the depth of penetration (unit: mm).
R is the radius of the ball indenter (2R = 0.4 mm).
H is the maximum value of the penetration depth h (unit: mm). △ H
/ Δf is the reciprocal of the slope of the load penetration depth curve of the load decreasing area when the load f is the maximum value F. n is the Poisson's ratio (n = 0.22) of the ball indenter material (WC)
Is. e is the elastic modulus of the material (WC) of the ball indenter (e =
It is 5.3 * 10 < ⁵ > N / mm < ² >).

As described above, the load increase / decrease and the like are repeated three times in the order of (1) to (4) to obtain the load dependence curve of the penetration depth for each time, and from each of the curves. The compression elastic modulus (E) (unit: Mpa) was obtained, and the average value thereof was used as the compression elastic modulus.

Creep Deformation Rate The creep deformation rate (C) was determined using the following formula. C = (h2−h1) · 100 / h1 where h1 is the penetration depth when a constant test load (here, 20 mN) is reached (point b in FIG. 2), and h2 is a predetermined value with the test load held. The penetration depth after a lapse of time (60 seconds) (point c in FIG. 2) is shown (unit: mm).

Elastic Deformation Rate FIG. 4 is a graph showing a load dependency curve of penetration depth. The elastic deformation rate is the ratio of the elastic deformation energy to the total load energy and can be obtained from the load dependence curve of the penetration depth in FIG. In FIG. 4, A: Initial state B: Maximum load load, maximum deformation BC: Cleave deformation amount D: After unloading (until minimum load) D-E: Cleave deformation amount at minimum load E-A: When the residual deformation amount h _max -E: recovery deformation amount, the elastic deformation rate (ηe) can be expressed by ηe = W _elastic / W _total . However, W _total = ∫F1 (h) dh W _elastic = ∫F2 (h) dh.

TV set crushing test A Fresnel lens sheet molded using a composition similar to each resin composition whose compression elastic modulus (E) and creep deformation ratio (C) described above was measured was given a lenticular lens. Align with the lens sheet and fix the four sides with tape,
It was fitted into a wooden frame of each TV size, mounted on a TV, and the white screen was visually observed and evaluated. When the Fresnel lens sheet was crushed after 1 hour, "X" was given, and when no crushing was observed, "O" was given.

Rub resistance test A Fresnel lens sheet and a lenticular lens sheet were adhered to each other at their lens surfaces, fixed on four sides with adhesive tape, and then fitted into a wooden frame of a TV screen size.
It was set on a vibration tester (a vibration tester, EDS252 manufactured by Akashi Co., Ltd.) installed in an environmental test chamber where the temperature was kept constant. As the vibration condition, the PSD (Po
The number of random waves shown in the wer Spectrum Density waveform is 4320 seconds, and one cycle is 5320.
A vibration test equivalent to a truck transport of 000 km was performed in 25
Ten cycles were performed at a temperature of 0 ° C, five cycles at a temperature of 0 ° C, and three cycles at a temperature of -20 ° C.

This random wave is an uncertain wave having statistical properties, and its properties can be expressed by a PSD function. In this vibration test, the test conditions are determined using the function as an index. The reason for using such a random wave is that the nonlinear element of vibration can be eliminated, that is,
This is because it becomes possible to excite the vibration of the object under a certain condition by eliminating the non-linear element due to the mounting of the projection screen and the packaging form. Also, the vibration is
This is because all of them are different on any time axis when the start of the test is 0, so that a situation closer to vibration during actual transportation can be created.

The environmental temperature is 25 ° C. (normal temperature), 0 ° C.,
And -20 ° C. After the test, when a white screen was projected by the projector, the uneven brightness due to rubbing was clearly recognized as ×, and the uneven brightness was observed but was inconspicuous. The case where no unevenness was observed was rated as ◯.

According to Table 1, for example, composition F, composition H, and
Urethanes (meta) used in this order when comparing J
The number average molecular weight of acrylate becomes large, and 80 ℃
The equilibrium elastic modulus of is decreased in this order. In composition J,
Equilibrium elastic modulus is 1.08 × 10 ⁸dyne / cm^Twothan
Low, plastic deformation easily occurs due to external force, TV set collapses
The results of the test and rubbing resistance test are not favorable.

Further, for Comparative Examples 1 to 9 in which the composition of the resin composition was changed, Table 2 shows the composition of each resin composition, the viscosity of each resin composition, the optical properties of the cured resin (refractive index, total light ray). Table 3 shows the adhesiveness with the substrate, the material properties of the resin composition (and the material properties (compressive elastic modulus, elastic deformation ratio, glass transition temperature, equilibrium elastic modulus, and dynamic friction coefficient)). The measurement method and conditions of each data are shown in Table 1.
It is similar to the case of.

[0106]

[Table 2]

[0107]

[Table 3] From the results of Table 2, from the resin compositions of Examples A to J
The cured product has a refractive index of 1.55 or more.
Glass transition temperature is 19.5 to 23.7 ° C., and
Equilibrium elastic modulus at ℃ is 1.08 × 10⁸~ 1.57 × 10⁸
dyne / cm ^TwoAnd the elastic deformation rate is We
(%) And the compression elastic modulus are expressed as E (MPa), W
The relationship of e> -0.0189E + 34.2 is satisfied. Well
In addition, in the examples, the adhesion to the base material may be excellent.
Recognize.

On the other hand, the urethane (meth) in Comparative Example 1
In the resin composition containing no acrylate (component A),
It can be seen that the glass transition temperature is lower than 19.5 ° C. and the equilibrium elastic modulus at 80 ° C. is higher than 1.57 × 10 ⁸ dyne / cm ² . That is, although the work rate with respect to elastic deformation increases and the restoring property is excellent, the viscosity is too lower than a predetermined value, which causes a problem in moldability.

Further, bisphenol A in Comparative Example 2
The resin composition containing no type epoxy (meth) acrylate (component B) has a glass transition temperature lower than 19.5 ° C. and an equilibrium elastic modulus at 80 ° C. of 1.57 × 10 ⁸ dyne.
Larger than / cm ² . That is, although the work rate against elastic deformation increases and the restorability is excellent, the viscosity of the resin composition is low and the problem of moldability occurs, and the refractive index is 1.
It is less than 55 and does not have performance as an optical element.

Further, in the resin composition in which the average molecular weight of the bisphenol A type epoxy (meth) acrylate (component B) in Comparative Example 3 was changed from 2100 to 500,
The refractive index is slightly lower than 1.55, the glass transition temperature is higher than 23.7 ° C, and the equilibrium elastic modulus at 80 ° C is 1.57 ×.
Greater than 10 ⁸ dyne / cm ² .

The resin composition of Comparative Example 4 in which the bisphenol A type epoxy (meth) acrylate (component B) was replaced with urethane (meth) acrylate (component A) had a refractive index lower than 1.55.

Further, the urethane (meth) in Comparative Example 5
The resin composition in which the acrylate (component A) was replaced with bisphenol A type epoxy (meth) acrylate (component B) had a glass transition temperature higher than 23.7 ° C.
Equilibrium elastic modulus at ° C is larger than 1.57 x 10 ⁸ dyne / cm ² . Further, the adhesiveness on the MS-based substrate is poor.

The resin composition containing a small amount of phenoxy polyethylene glycol (meth) acrylate (component C) in Comparative Example 6 had a glass transition temperature of 23.7.
Higher than ℃, equilibrium elastic modulus at 80 ℃ is 1.57 × 10 ⁸
It is larger than dyne / cm ^2, and the adhesiveness is poor in both the PMMA-based substrate and the MS-based substrate. Moreover, the viscosity of the resin composition is abnormally high.

Further, phenoxyethyl in Comparative Example 7
Change acrylate by ethylene oxide by 5-6 mol
The glass transition temperature of the resin composition
The degree is lower than 19.5 ℃ and the equilibrium elastic modulus at 80 ℃ is 1.
57 x 10⁸dyne / cm ^TwoGreater resilience ability
Is high, but the refractive index is small and PMMA-based
It also has poor adhesion to the substrate.

In the resin composition containing no bisphenol A diacrylate modified by ethylene oxide on average with a total of 10 moles in Comparative Example 8, the resin composition had a high viscosity and a glass transition temperature higher than 23.7 ° C. , Storage modulus at 80 ° C. 1.08 × 10 ⁸ dyne / c
It is smaller than m ² .

Also, in Comparative Example 9, bisphenol A modified with ethylene oxide on average 10 mol in total.
In the resin composition in which the diacrylate was replaced with bisphenol A diacrylate modified with an average of 4 mol of ethylene oxide, the glass transition temperature was higher than 23.7 ° C. and the equilibrium elastic modulus at 80 ° C. was 1.57 × 10 ^8. dy
It is larger than ne / cm ^{2, and the} adhesion to the MS-based substrate is poor. This is not a good restorer,
It is a rigid material with high energy elasticity.

Examples 1 to 3 and Comparative Examples 10 to 12 To the resin composition of the composition B shown in Table 1 above, 0.4% by weight of the releasing agent shown in Table 4 was added, and the polyether-modified polydimethyl was used as an additive. Siloxane (L-70 manufactured by Nippon Unicar Co., Ltd.)
01) in an amount of 0.5% by weight, and a fluorine-based leveling agent (manufactured by Dainippon Ink and Chemicals, Inc., Megafac F-
470) 0.1% by weight was used to prepare a sheet lens in the same manner as above. In order to examine the compatibility of each release agent with the polyether-modified polydimethylsiloxane, the state of the mixed solution in which the release agent and the polyether-modified polydimethylsiloxane were mixed at a ratio of 1: 1 was visually evaluated. . When the solution was transparent, it was marked with ◯, and when it was cloudy or separated, it was marked with x. Furthermore, the fluidity of the mixed solution at −10 ° C. was examined. The mixed solution was weighed in a glass bottle and stored at -10 ° C. Tilting the glass bottle of the mixed solution at −10 ° C. by 90 °, the solution that immediately flowed (clearly in a liquid state) was marked with ◯, and the solid or wax-like one without fluidity was marked with x. .

[0118]

[Table 4]

As a mold releasability at the time of producing a sheet lens, a transmittance of the sheet lens, a haze value, and an acceleration test, the obtained lens sheet was treated at 60 ° C. and 95% R.
After being kept under the condition of H for 168 hours, the transmittance, haze value and lens surface state of the lens sheet were evaluated. Further, the obtained lens sheet was subjected to a vibration test at −20 ° C. in the same manner as above. The results are shown in Table 5.

[0120]

[Table 5] In Examples 1 to 3, the mold release from the mold was excellent, the obtained lens sheets were highly transparent, and the stability over time was excellent.

On the other hand, the lens sheet obtained in Comparative Example 10 had a poor releasability, did not maintain transparency in a hot and humid environment, and was inferior in stability over time. Further, the lens sheet obtained in Comparative Example 11 has excellent stability over time in a high temperature and high humidity environment, but has poor releasability. The lens sheet obtained in Comparative Example 12 has excellent stability over time in a high temperature and high humidity environment, but the chain length of the alkyl group of the phosphate ester used is short (n =
4), the releasability was at an insufficient level.

[Brief description of drawings]

FIG. 1 is a schematic diagram for explaining a load dependence curve of penetration depth.

FIG. 2 is a schematic view showing a portion where an indenter acts.

FIG. 3 is a graph of a PSD waveform used in a vibration test.

FIG. 4 is a schematic diagram for explaining a load dependence curve of penetration depth.

[Explanation of symbols]

2 Fresnel lens sheet

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Toshiyuki Tanimura             450 Aoto-cho, Midori-ku, Yokohama-shi, Kanagawa The             Inktech Co., Ltd. (72) Inventor Makoto Nakao             450 Aoto-cho, Midori-ku, Yokohama-shi, Kanagawa The             Inktech Co., Ltd. F-term (reference) 4J011 PA46 PA90 PA99 PB32 PB33                       PC02 PC08                 4J027 AC03 AC06 AC08 AE02 AG04                       AG09 AG23 AG24 AG27 AJ05                       AJ06 AJ09 BA05 BA07 BA11                       BA12 BA13 BA15 BA19 BA20                       BA24 BA26 BA27 CA10 CA27                       CB10 CC04 CC05 CC06 CC08                       CD04

Claims (9)

[Claims] 1. Bisphenol A as an oligomer component
Urethane (meth) acrylate obtained by reacting polyalkoxy diol, organic diisocyanate and hydroxyl group-containing mono (meth) acrylate, and bisphenol A type epoxy (meth) acrylate, phenoxy polyethylene glycol (meth) acrylate as a monomer component, and A resin composition comprising bisphenol A polyethoxydiol di (meth) acrylate and a photopolymerization initiator, and having a refractive index of 1.55 or more after resin curing. 2. The resin composition according to claim 1, which comprises a polyether-modified polydimethylsiloxane as an additive. 3. The resin composition according to claim 2, further comprising a phosphoric acid ester represented by the following formula I or a phosphonic acid ester represented by the following formula II as the internal release agent. . [Chemical 1] (Here, n represents an integer of 4 or more.) (Here, n represents an integer of 4 or more.) 4. The urethane chain concentration of the urethane oligomer contained in the resin composition is 0.5 to 1.3 mmol / g.
The resin composition according to claim 3, wherein the release agent content is 0.1 to 0.5% by weight based on the resin composition. 5. The urethane chain concentration of the urethane oligomer contained in the resin composition is 0.28 mmol / g or more, and the concentration of OH groups contained in the resin composition is 0.
The resin composition according to claim 3, wherein the content of the release agent is 0.1 to 1.0% by weight based on the resin composition when the amount is 41 to 1.2 mmol / g. 6. A glass transition temperature of 19.5 ° C. to 23.7 ° C.
And the equilibrium elastic modulus at 80 ° C. is 1.08
The resin composition according to any one of claims 1 to 5, which has a viscosity of × 10 ^{8 to} 1.57 × 10 ⁸ dyne / cm ² . 7. Elastic deformation rate is We (%), compression elastic modulus is E
When expressed as (MPa), We> -0.0189E +
Any one of Claims 1-7 satisfying the relationship of 34.2.
The resin composition according to item. 8. An optical element comprising the resin composition according to any one of claims 1 to 7. 9. The optical element is a Fresnel lens,
The optical element according to claim 8.