JP2000147220A - Light scattering body having adherent properties - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a light scattering body comprising or having a cured film having adherent properties, excellent in flexibility and excellent also in adaptability even to a curved surface. SOLUTION: A UV curing type adhesive composition based on a copolymer of at least one diallyl phthalate component and pentaerythritol tetra (3- mercaptopropionate) is prepared and particles whose refractive index is different from that of the copolymer are added and dispersed in the composition. The objective light scattering body is formed using the resultant composition. The equivalent ratio between the diallyl phthalate component and the pentaerythritol tetra (3-mercaptopropionate) is preferably 2:1 to 1:3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light scatterer having an ultraviolet-curing adhesive.

[0002]

2. Description of the Related Art Conventionally widely used light diffusing materials include:
The transmitted light is scattered by providing fine irregularities on the surface of glass or transparent resin, or by uniformly dispersing transparent particles having different refractive indices in glass or transparent resin.
Alternatively, a technique has been proposed in which light is scattered by coating the surface of a transparent body with a cured film of a mixture of silane compounds containing fine particles.

However, in the method of performing fine processing on the surface of glass or transparent resin, irregularities are easily stained, and when a liquid such as water or oil adheres to the surface, the haze value is reduced and the transparency is reduced. Getting worse. In addition, the method of mixing particles in a transparent body or the method of coating the transparent body with a cured film eliminates the above-mentioned problem, but the material for dispersing the fine particles is hard and self-adhesive such as glass or resin. When the obtained scatterer is used in combination with other base materials, it takes time and effort to attach the scatterer, and since it is a rigid body, it has the ability to follow a shape with a curved surface. However, there are problems that the use is extremely limited, and a processing step for mounting on a base material is required, which increases costs.

[0004]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned problems of the prior art, and comprises a cured film having adhesiveness, excellent flexibility, and excellent followability even on a curved surface. Or
Alternatively, it is an object to provide a light scatterer having such a cured film.

[0005]

Means for Solving the Problems The present inventor has disclosed a UV-curable adhesive composition containing a copolymer of a specific vinyl compound and a polythiol compound as a main component, which has a refractive index different from that of the copolymer. By adding and dispersing different particles,
The present inventors have found that a light scatterer having adhesiveness can be obtained, and completed the present invention.

That is, the light-scattering body having adhesiveness of the present invention is an ultraviolet-curable adhesive comprising a copolymer of at least one diallyl phthalate component and pentaerythritol tetra (3-mercaptopropionate) as a main component. The composition is characterized in that particles having a different refractive index from the copolymer are added and dispersed in the hydrophilic composition.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The light scatterer of the present invention has an ultraviolet-curable matrix whose matrix is mainly composed of a copolymer comprising at least one diallyl phthalate component and pentaerythritol tetra (3-mercaptopropionate). It consists of an adhesive composition. The diallyl phthalate component has three isomers, orthophthalate, isophthalate, and terephthalate, and one or more of these can be used in combination.

[0008] The diallyl phthalate component and pentaerythritol tetra (3-mercaptopropionate) contained in the ultraviolet-curable adhesive composition are in an equivalent ratio of 2: 1.
１ ： 1: 3, preferably 1.2: 1.
More preferably, they are blended in a ratio of 1-1 to 1.3.
If blended at an equivalent ratio outside this range, polymerization will not be completed,
Insufficient curing may result in significantly reduced strength and durability.

The physical properties of the light scatterer of the present invention, for example,
An allyl compound can be added to the ultraviolet-curable adhesive composition for improving or adjusting mechanical strength, adhesiveness, optical performance, heat resistance, moisture resistance, weather resistance, and the like. Examples of the allyl compound added here include triallyl cyanurate, triallyl isocyanurate, diallyl maleate, and the like, and one or more of these can be used in combination. The allyl compound can be added in an amount of 0.1 to 30 parts by weight, preferably 0.5 to 10 parts by weight, based on 100 parts by weight of the copolymer in the ultraviolet-curable adhesive composition. If the amount is less than 0.1 part by weight, the mechanical strength of the light scatterer may decrease, and if it exceeds 30 parts by weight, the adhesiveness, workability and film formability may decrease.

The ultraviolet-curable adhesive composition used in the present invention further contains a photopolymerization initiator. The photopolymerization initiator is
It is preferable to add 0.005 to 10 parts by weight to 100 parts by weight of the copolymer. When the addition amount of the photopolymerization initiator is less than 0.005 parts by weight, a polymerization reaction sufficient for curing does not occur, and the mechanical strength may decrease,
When the amount exceeds 10 parts by weight, a reaction occurs rapidly after the photopolymerization initiator is added, and the stability as a solution is impaired.

The photopolymerization initiator is not particularly limited.
Various types can be used, for example, benzoin,
Benzyl, benzoin methyl ether, acetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1- (4-isopropylphenyl) -2
-Hydroxy-2-methylpropan-1-one, 4-
(2-hydroxyethoxy) phenyl- (2-hydroxy-2-propyl) ketone, 1-hydroxycyclohexylphenylketone, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl- [4- (methylthio)
Phenyl] -2-morpholino-1-propan-1-one, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butan-1-one, benzophenone, 4,4′-bis (dimethylamino ) Benzophenone, 4,4'-bis (diethylamino) benzophenone, N, N-dimethylaminoacetophenone, 2-methylanthraquinone, 2-ethylanthraquinone, 1-chloroanthraquinone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone , 2,4
6-trichloromethyl-s-triazine, 2- (p-chlorophenyl) -4,6-bis (trichloromethyl)-
s-triazine, 2- (p-tolyl) -4,6-bis (trichloromethyl) -s-triazine, 2,4-bis (trichloromethyl) -4′-methoxyphenyl-s-
Triazine, 2- (4-methoxy-naphth-1-yl)
-4,6-bis (trichloromethyl) -s-triazine, 2-p-methoxystyryl-4,6-bis (trichloromethyl) -s-triazine, 2- (2 ', 4'-dimethoxystyryl) -4 , 6-bis (trichloromethyl) -s-triazine, 2,2'-bis (o-chlorophenyl) -4,4 ', 5,5'-tetraphenylbisimidazolyl, 2,2'-bis (o-chlorophenyl )-
4,4 ', 5,5'-tetra- (p-methoxyphenyl) bisimidazolyl, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, bisacylphosphine oxide, triphenylphosphine, triphenylphosphite, trilauryl-triti Ophosphite, bis (2,6-dimethoxybenzoyl) -2,4
4-trimethylpentylphosphine oxide, (η ⁵
~ 2,4-cyclopentadien-1-yl) [(1,
2,3,4,5,6-η)-(1-methylethyl) benzene] -iron (1 +)-hexafluorophosphate (1-) and the like, alone or in combination of two or more. Can be used. Among these, it is particularly preferable to use a combination of 2-hydroxy-2-methyl-1-phenylpropan-1-one and bisacylphosphine oxide. Further, such a photopolymerization initiator is used as N, N-dimethylaminobenzoic acid ethyl ester, N, N-dimethylaminobenzoic acid isoamyl ester, triethanolamine, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, It can be used in combination with one or more known photosensitizers such as mercaptobenzimidazole and 2-mercapto-5-methylthio-1,3,4-thiazole.

As the light source which is the object of the light-scattering body having adhesiveness of the present invention, there are various light sources such as sunlight, fluorescent lamp and LED. Among them, not only visible light but also ultraviolet light harmful to the human body is used. Many light sources emit the light. For this reason, an ultraviolet absorber can be added to the composition for the purpose of suppressing ultraviolet light in the light scatterer of the present invention. The ultraviolet absorber is preferably added at a ratio of 0.01 to 3.0 parts by weight based on 100 parts by weight of the copolymer. If the added amount of the ultraviolet absorbent is less than 0.01 part by weight, a sufficient ultraviolet absorbing effect cannot be obtained, and if it exceeds 3.0 parts by weight, the ultraviolet absorbent is saturated and cannot be dissolved.

The UV absorber is not particularly limited as long as it is soluble in one or both of the monomers, and various UV absorbers can be used. For example, 2-hydroxybenzophenone, 2,4-hydroxybenzophenone Benzophenones, salicylates such as phenyl salicylate, (2'-hydroxyphenyl) benzotriazole, (2'-hydroxy-5'-methylphenyl)
Benzotriazole, 2,2-methylenebis [4-
(1,1,3,3-tetramethylbutyl) -6- (2H
-Benzotriazol-2-yl) phenol] and the like, and these can be used alone or in combination of two or more.

[0014] In addition to the above-mentioned additives, an antioxidant, a dye, a processing aid and the like can be added to the ultraviolet-curable adhesive composition used in the present invention as long as the effects of the present invention are not impaired.

On the other hand, the particles to be added and dispersed in the ultraviolet-curable adhesive composition (matrix) may be those having a different refractive index from the above-mentioned copolymer, for example, glass, quartz, silicon oxide, Examples include inorganic substance particles such as calcium carbonate, titanium oxide, and zinc oxide, and organic polymer substance particles such as silicone resin, acrylic resin, polyethylene, polystyrene, and polyurethane. Further, the inorganic substance particles as described above may be surface-treated with a surface treatment agent such as a silane coupling agent. These particles are used in an amount of 0.01 to 0.3, especially 0.05 to 0.2, with the copolymer.
Having a refractive index difference of 0.5 to 200 μm
m, particularly preferably 1 to 100 μm. If the refractive index difference is outside the above range, sufficient scattering cannot be obtained. If the average particle size is outside the above range, the dispersibility of the particles in the ultraviolet-curable adhesive composition will be poor.

The addition amount of the particles is preferably 0.05 to 50 parts by weight, more preferably 0.1 to 40 parts by weight, based on 100 parts by weight of the copolymer. When the addition amount of the particles is less than 0.05 parts by weight,
If a sufficient light scattering effect is not obtained and exceeds 50 parts by weight,
The dispersibility of the particles in the matrix becomes poor, and the sheet may become uneven.

In order to produce the light scatterer of the present invention, the components of the composition and the particles are uniformly mixed, and an extruder is used.
After kneading with a roll or the like, the kneaded material can be formed into a desired shape by a film forming method such as calender, roll, T-die extrusion, or inflation and used. The sheet obtained as described above has an adhesive property, so that it can be semi-permanently bonded only by hand pressing to another object,
Also, it can be easily peeled off by hand.

The sheet obtained as described above can be bonded to a substrate by a commonly used method. For example, lamination can be performed using a method such as a laminating method using a hot press, a direct laminating method using an extruder or a calender, or a thermocompression bonding method using a film laminator. In addition, the above composition is directly or uniformly dissolved in a type of solvent having no effect on the substrate, uniformly applied to the surface of the substrate, and directly cured by ultraviolet light to obtain a light scattering body. Can also. In this case, the above-described film forming methods such as calender, roll, T-die extrusion, and inflation can be used. The thus obtained light-scattering body having a laminated structure can also be bonded by pressing the ultraviolet-cured layer side against another object.

[0019]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited by these examples.

Example 1 100.4 parts by weight of diallyl phthalate, pentaerythritol tetra (3-mercaptopropionate) 99.
6 parts by weight, 2-hydroxy-2-methyl-1-phenylpropan-1-one as a photopolymerization initiator (trade name Darocure 1 manufactured by Ciba Specialty Chemicals Co., Ltd.)
173) 0.2 parts by weight and 4 parts by weight of surface-treated calcium carbonate (Chemipron A, manufactured by Chemipro Kasei Co., Ltd.) were added and mixed in a dark place. The obtained polymer composition was uniformly coated on a polyester film by a T-die method, and the output was 80 W.
Was irradiated with ultraviolet rays by a metal halide lamp of No. 1 to obtain a 20 μm light scatterer on the polyester film. The haze value and the total light transmittance of the light scatterer thus prepared were measured using a color computer (trade name: SM, manufactured by Suga Test Instruments Co., Ltd.).
As measured by -5), the haze value was 52.4% and the total light transmittance was 93.6%. The light-scattering body film was placed on a halogen lamp, and the front luminance (luminance meter, S-100 manufactured by Minolta) was measured.
/ M ² .

Example 2 A light-scattering body film was prepared in the same manner as in Example 1 except that diallyl phthalate was changed to diallyl isophthalate. The haze value is 51.8% and the total light transmittance is 9
3.1%. The front luminance is 2350 cd / m.
^{Was 2} .

Example 3 A light-scattering body film was produced in the same manner as in Example 1 except that diallyl phthalate was changed to diallyl terephthalate. The haze value is 52.8% and the total light transmittance is 9
It was 3.4%. The front luminance is 2300 cd / m
^{Was 2} .

Example 4 The diallyl component in the polymer composition was diallyl phthalate 5
A light-scattering body film was produced in the same manner as in Example 1, except that 0.2 parts by weight and 50.2 parts by weight of diallyl isophthalate were used. The haze value was 52.9% and the total light transmittance was 93.1%. The front luminance is 2380c
d / m ² .

Comparative Example 1 1,1-bis (t-butylperoxy) -3 was added to 100 parts by weight of an ethylene-vinyl acetate glycidyl methacrylate copolymer (trade name: Pound First 2A, manufactured by Sumitomo Chemical Co., Ltd.). , 3,5-trimethylcyclohexane, 2 parts by weight of γ-glycidoxypropyltrimethoxysilane, and 5 parts by weight of calcium carbonate were added, and the mixture was sufficiently kneaded with a mixing roll at a temperature of 70 ° C., followed by a roll coater. Coated on polyester film and dried. Next, the coating was cured by leaving it in an oven at 130 ° C. for 30 minutes to obtain a light-scattering body film. The haze value was 11.4% and the total light transmittance was 80.7%.
Further, the front luminance was measured in the same manner as in Example 1, and was found to be 1000 cd / m ² .

[0025]

The light scatterer of the present invention is an uncured liquid,
Alternatively, it is provided in a cured film form and has adhesiveness, so that it is possible to eliminate the trouble of applying an adhesive when bonding various substrates in a conventional light scatterer, and the light scatterer formed into a film is It can be semi-permanently adhered by pressing it against the object by hand, it can be easily peeled off by hand, and it is more flexible than the conventional one, so it has a curved surface that is not flat Combinations with are also possible. In addition, since it has a cross-linked structure by ultraviolet curing, it has excellent durability.

Continued on the front page F-term (reference) 2H042 BA01 4J030 BA43 BA44 BB06 BC12 BC15 BC33 BC36 BC40 BC43 BE02 BE04 BF09 BG25 4J040 DA022 DB032 DE041 DF042 EF002 EK032 HA136 HA196 HA306 HA346 HA356 HB19 HD03 JB08 KA10 KA13 MA05

Claims (3)

[Claims] 1. An ultraviolet-curable adhesive composition containing a copolymer of at least one diallyl phthalate component and pentaerythritol tetra (3-mercaptopropionate) as a main component, the copolymer and the refractive index A light-scattering body having adhesiveness, characterized by adding and dispersing particles having different properties. 2. The adhesive according to claim 1, wherein the ultraviolet-curable adhesive composition contains a diallyl phthalate component and pentaerythritol tetra (3-mercaptopropionate) in an equivalent ratio of 2: 1 to 1: 3. A light scatterer having: 3. The light scattering material having adhesiveness according to claim 1, wherein the particles having a different refractive index from the copolymer are inorganic material particles or organic polymer material particles.