JPH08199046A - Thermoplastic resin composition - Google Patents

Abstract

PURPOSE: To obtain a thermoplastic resin composition which can give a molding excellent in durability and light diffusivity under high-temperature high-humidity conditions by mixing a thermoplastic norbornene resin with a specified light diffusing agent in a specified ratio. CONSTITUTION: This composition comprises 100 pts.wt. thermoplastic norbornene resin (a resin obtained by subjecting 6-ethylidene-2-tetracyclododecene to a metathesis ring opening polymerization reaction and hydrogenating the obtained product), 0.1-100 pts.wt., desirably 0.5-30 pts.wt., more desirably 1-10 pts.wt. light diffusing agent (e.g. crosslinked polymer particles obtained by allowing a seed polymer obtained by polymerizing styrene, methyl methacrylate and methacrylic acid to absorb methyl methacrylate and divinylbenzene and polymerizing the absorbed monomers) having a mean particle diameter of 0.1-50μm, desirably 0.5-30μm, more desirably 1.0-20μm.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a thermoplastic resin composition, and a thermoplastic resin which has a particularly excellent light-diffusing function and also has excellent durability under high temperature and high humidity. It relates to a composition.

[0002]

2. Description of the Related Art Molded products having a light diffusing function, which are used for a light guide plate and a light diffusing plate of a backlight of a liquid crystal display, a lighting cover, etc. It has been demanded. Conventionally, as a molded product having such a light diffusing function, a surface of a molded product such as a sheet made of a transparent resin is embossed, a pattern of a predetermined shape is formed by a photocurable resin, or a coating agent containing resin beads is applied. Some of them have been subjected to a surface treatment such as to give a light diffusing function, but there is a problem that productivity is inferior because the manufacturing process is complicated. On the other hand, a resin composition obtained by mixing inorganic base particles such as barium sulfate, calcium carbonate, quartz, aluminum hydroxide in a transparent base resin is molded into a molded article having a light diffusion function by injection molding or extrusion molding. The method is disclosed in JP-A-57-5742, JP-A-57-155245, and JP-A-57-1.
No. 62743, Japanese Patent Application Laid-Open No. 61-4762, Japanese Patent Publication No. 4-11842, etc., and a resin composition is injection-molded or extrusion-molded by blending the resin with cross-linked polymer particles having a different refractive index. The method of molding into a molded article having a light diffusing function is disclosed in JP-B-55-7471, JP-B-58-11463, and JP-A-1-236.
No. 257, JP-A-1-301745, and JP-A-4-328148. Many of the techniques disclosed in these publications use a polymethylmethacrylate resin (PMMA) as a transparent base resin, but PMMA has a low heat distortion temperature, poor heat resistance, and high water absorption. The light guide plate and the light diffusion plate made of resin may be deformed under high temperature and high humidity.

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned problems of the prior art, and it is a thermoplastic resin capable of obtaining a light diffusion molded article excellent in light diffusion property, heat resistance and productivity. It is intended to provide a resin composition.

[0004]

The thermoplastic resin composition of the present invention comprises 100 parts by weight of a thermoplastic norbornene resin (a) and a light diffusing agent (b) 0.1 having an average particle diameter of 0.1 to 50 μm. To 100 parts by weight. The thermoplastic norbornene resin used in the present invention has a norbornane skeleton in its repeating unit.
For example, as the thermoplastic resin, general formula (I)
It contains a norbornane skeleton represented by (IV).

[0005]

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[0006]

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[0007]

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[0008]

[Chemical 4]

(In the formula, A, B, C and D represent a hydrogen atom or a monovalent organic group.) Examples of the thermoplastic resin having a norbornane skeleton which can be used in the present invention include those disclosed in Japanese Patent Laid-Open No. 60-1
68708, JP-A-62-252406,
JP 62-252407 A, JP 2-1334
Resins described in JP-A No. 13, JP-A-63-145324, JP-A-63-264626, JP-A-1-240517, JP-B-57-8815 and the like can be mentioned. . Specific examples of the thermoplastic resin include metathesis polymerization of at least one tetracyclododecene derivative represented by the following general formula (V) or an unsaturated cyclic compound copolymerizable with the tetracyclododecene. The hydrogenated polymer obtained by hydrogenating the obtained polymer can be mentioned.

[0010]

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(In the formula, A to D are the same as above.) In the tetracyclododecene derivative represented by the general formula (V), it is preferable that A, B, C and D contain a polar group. It is preferable in terms of heat resistance, dispersibility of crosslinked polymer particles, and adhesion with other molded products. Furthermore, this polar group is
(CH ₂ ) _n COOR ³ (wherein R ³ has 1 to 2 carbon atoms.
A hydrocarbon group of 0 and a group represented by n is an integer of 0 to 10) are preferable because the hydrogenated polymer obtained has a high glass transition temperature. Especially this −
It is preferable that one polar substituent represented by (CH ₂ ) _n COOR ³ is contained per molecule of the tetracyclododecene derivative represented by the general formula (V).

In the above-mentioned general formula (V), R ¹ is a hydrocarbon group having 1 to 20 carbon atoms, and it is preferable that the hydrogen absorption of the hydrogenated polymer obtained becomes smaller as the carbon number increases, but it is obtained. From the viewpoint of the balance with the glass transition temperature of the hydrogenated polymer to be used, a chain alkyl group having 1 to 4 carbon atoms or a (poly) cyclic alkyl group having 5 or more carbon atoms is preferable, and a methyl group or an ethyl group is particularly preferable. It is preferably a cyclohexyl group. Furthermore, since the tetracyclododecene derivative of the general formula (V) in which a hydrocarbon group having 1 to 10 carbon atoms is simultaneously bonded as a substituent to the carbon atom to which the carboxylic acid ester group is bonded reduces hygroscopicity. preferable. Particularly, the tetracyclododecene derivative represented by the general formula (V) in which the substituent is a methyl group or an ethyl group is preferable in that the synthesis thereof is easy. Specifically, 8-methyl-8
-Methoxycarbonyltetracyclo [4.4.0.1
^{2,5 17,10} ] dodeca-8-ene is preferred. These tetracyclododecene derivatives or a mixture of unsaturated cyclic compounds copolymerizable therewith are disclosed, for example, in JP-A-4-77.
No. 520, page 4, upper right column, line 12 to page 6, lower right column, sixth
The thermoplastic resin used in the present invention can be obtained by metathesis polymerization and hydrogenation according to the method described in the row. In addition, the glass transition temperature (T
g) is preferably in the range of 100 ° C to 200 ° C. If the temperature is lower than 100 ° C, the heat resistance of the molded article made of the resin composition is poor. If the Tg exceeds 200 ° C., the molding temperature becomes high, and it becomes difficult to obtain a good quality molded product. The hydrogenation rate of the hydrogenated polymer is 60 MHz, ¹
The value measured by 1 H-NMR is 50% or more, preferably 90%.
% Or more, more preferably 98% or more. The higher the hydrogenation rate, the better the stability to heat and light. In addition,
In the hydrogenated polymer used as the thermoplastic resin having the norbornane skeleton of the present invention, the gel content contained in the hydrogenated polymer is preferably 5% by weight or less, and further 1% by weight. Is preferred.

Component (b) (Light Diffusing Agent) In the present invention, the light diffusing agent (b) blended in the thermoplastic norbornene-based resin composition (a) is a spherical or true spherical fine particle made of an inorganic material or an organic material. Is. A resin composition containing inorganic fine particles as a light diffusing agent can obtain a molded article having particularly excellent heat resistance. In addition, a lightweight molded product can be obtained from the resin composition containing the organic fine particles. Further, a mixture of these inorganic fine particles and organic fine particles may be used. Examples of fine particles made of an inorganic material that are preferably used as the light diffusing agent (b) include glass beads, silica, talc, titanium oxide, barium sulfate,
Examples thereof include aluminum oxide, aluminum hydroxide, calcium carbonate, magnesium carbonate and quartz. Also,
Crosslinked polymer particles are preferably used as the fine particles made of an organic material. As a method for producing the crosslinked polymer particles,
For example, JP-A-63-189413 and JP-A-1-3
The method described in Japanese Patent No. 15454 can be used, and specifically, the weight average molecular weight is 500 to
1% by weight of seed polymer particles in the range of 10,000
100 parts by weight of an aqueous dispersion containing 3 parts of a crosslinkable monomer
It is possible to use a method in which 2 to 500 parts by weight of a polymerizable monomer containing at least wt% is added, and the seed polymer particles are allowed to absorb the polymerizable monomer and polymerize. The composition of the seed polymer particles is not limited as long as it dissolves or swells in the monomer used for polymerization, but is preferably of the same type as the monomer used for polymerization. In particular,
Polystyrene, polymethyl methacrylate, poly n-butyl acrylate, styrene-butadiene copolymer, and other polymer particles are preferably used.

As the crosslinkable monomer, two or more, preferably two or more, such as a non-conjugated divinyl compound represented by divinylbenzene or a polyvalent acrylate compound represented by trimethylolpropane trimethacrylate, trimethylolpropane triacrylate, etc. The compound having a copolymerizable double bond can be preferably used. Examples of the polyvalent acrylate compound that can be used in the present invention include the following compounds. Diacrylate compound polyethylene glycol diacrylate, 1,3-butylene glycol diacrylate, 1,6-hexane glycol diacrylate, 1,6-hexane glycol diacrylate, neopentyl glycol diacrylate, polypropylene glycol diacrylate, 2,2
-Bis (4-acryloxyproproxyphenyl) propane, 2,2-bis (4-acryloxydiethoxyphenyl) propane triacrylate compound trimethylolpropane triacrylate, trimethylolethane triacrylate, tetramethylolmethane triacrylate dimethacrylate Compounds ethylene glycol dimethacrylate, diethylene glycol dimethacrylate, triethylene glycol dimethacrylate, polyethylene glycol dimethacrylate, 1,3-butylene glycol dimethacrylate,
1,4-butylene glycol dimethacrylate, 1,6
-Hexane glycol dimethacrylate, neopentyl glycol dimethacrylate, dipropylene glycol dimethacrylate, polypropylene glycol dimethacrylate, 2,2-bis (4-methacryloxydiethoxyphenyl) propane trimethacrylate compound trimethylolpropane trimethacrylate, trimethylolethane Trimethacrylate Among the above, divinylbenzene, ethylene glycol dimethacrylate, or trimethylolpropane trimethacrylate is preferably used, and divinylbenzene is particularly preferable. These crosslinkable monomers may be used alone or in admixture of two or more.

The polymerizable monomer used together with the crosslinkable monomer includes aromatic vinyl compounds such as styrene, α-methylstyrene, fluorostyrene and vinylpyridine; vinyl cyanide compounds such as acrylonitrile and methacrylonitrile; butyl ( (Meth) acrylate, 2-ethylhexyl (meth) acrylate, methyl (meth) acrylate, 2-hydroxyethyl (meth)
(Meth) acrylates such as acrylate and glycidyl (meth) acrylate; unsaturated fatty acids such as acrylic acid, methacrylic acid, maleic acid and itaconic acid; and amide monomers such as acrylamide and methacrylamide. The glass transition temperature (Tg) of the crosslinked polymer particles is preferably 100 ° C. or higher in order not to significantly impair the heat resistance of the molded article obtained from the thermoplastic resin composition of the present invention. In particular, when the thermoplastic resin composition of the present invention is molded at a temperature at which the (a) cyclic polyolefin resin is heated and melted, such as injection molding and extrusion molding,
It is desirable that the crosslinked polymer particles do not melt at the heating temperature.

The particle size of the light diffusing agent (b) used in the present invention is usually 0.1 to 50 μm, preferably 0.5 to 30.
μm, and more preferably 1.0 to 20 μm. When the particle size is less than 0.1 μm, the light diffusivity becomes too strong, the total light transmittance of the sheet or resin plate obtained by molding is lowered, and the production of crosslinked fine particles becomes difficult. Also, 5
If it exceeds 0 μm, the uniformity of light diffusion of the sheet or resin plate obtained by molding is deteriorated. In the present invention, the refractive index of the light diffusing agent (b) needs to be different from the refractive index of the cyclic polyolefin resin (a). When the refractive index of (b) is the same as the refractive index of (a), no light diffusing property is obtained, but the larger the difference in refractive index between the two components is, the wider the incident light is diffused. However, as the amount of diffused light increases, the amount of reflected light at the interface of the diffusing agent also increases, so the light transmittance decreases. Therefore, in order to obtain a molded article having an excellent balance of transparency and light diffusivity, it is desirable to set the compounding amount of (b) within a specific range, and to 100 parts by weight of the component (a),
The amount is 0.1 to 100 parts by weight, preferably 0.5 to 30 parts by weight, and more preferably 1 to 10 parts by weight. When the amount of the crosslinked polymer particles used is less than 0.1 part by weight, the light diffusivity is insufficient, while when it exceeds 100 parts by weight, the total light transmittance decreases.

When the light diffusing agent (b) is a crosslinked polymer particle, the refractive index of the particle can be obtained by appropriately adjusting the type and amount of the monomer used. In the thermoplastic resin composition of the present invention, if necessary, a known antioxidant such as 2,6-di-t-butyl-4-methylphenol, 2, within a range that does not impair the effects of the present invention.
2'-dioxy-3,3'-di-t-butyl-5,5 '
-Dimethylphenylmethane, tetrakis [methylene-3
-(3,5-di-t-butyl-4-hydroxyphenyl) propionate] methane, 1,1,3-tris (2
-Methyl-4-hydroxy-5-t-butylphenyl)
Butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-t-butyl-4-hydroxybenzyl-
Benzene, stearyl-β- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,2 ′
-Dioxy-3,3'-di-t-butyl-5,5'-diethylphenylmethane, 3,9-bis [1,1-dimethyl-2- [β- (3-t-butyl-4-hydroxy -5
-Methylphenyl) propionyloxy] ethyl],
2,4,8,10-Tetraoxpyro [5,5] undecane, tris (2,4-di-t-butylphenyl) phosphite, cyclic neopentanetetraylbis (2,4-di-t-) Butylphenyl) phosphite, cyclic neopentanetetraylbis (2,6-di-
t-butyl-4-methylphenyl) phosphite, 2,
2-methylenebis (4,6-di-t-butylphenyl)
Octyl phosphite can be added. In the thermoplastic resin composition of the present invention, in addition to the above-mentioned antioxidant, if necessary, an ultraviolet absorber such as p-t-butylphenyl salicylate, 2,2'-dihydroxy-4-.
Methoxybenzophenone, 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2- (2'-dihydroxy-4'-m-octoxyphenyl) benzotriazole; stabilizer, antistatic agent,
Dyes, color pigments, flame retardants, impact resistance improving elastomers, etc. can be added. Further, additives such as a lubricant may be added for the purpose of improving processability.

As an example of the method for producing the resin composition of the present invention, the components (a) and (b) or, if necessary, the above-mentioned various additives are added to a twin-screw extruder, a Brabender, or a roll kneader. A method of mixing and pelletizing by mixing the components (a) as a solution and then mixing the components (b) or various additives into the solution.
The resin composition of the present invention can be made into a desired molded product by a known molding method such as injection molding, extrusion molding, compression molding or the like. Further, when the component (a) is used as a solution, the film can be produced by a cast molding method. The molded product comprising the resin composition of the present invention can be used as it is as a molded product having a light diffusing property for various purposes, but if necessary, an arbitrary pattern is formed on the surface of the molded product by embossing or a photocurable resin. It is also possible to supplement the light diffusing performance by applying a surface treatment such as applying a coating agent containing glass or resin beads, or to give a lens shape such as a lenticular lens. When a mold is used, a desired pattern may be formed on the mold surface in advance, and the pattern may be transferred at the same time as the molding to obtain a patterned molded product. Further, a light reflecting layer of a white pigment or the like can be formed on the surface opposite to the pattern forming surface of the patterned molded article, but the method for forming the light reflecting layer is not particularly limited, and the entire surface of the molded article is coated or coated. It may be printed, and has any shape, area, distribution such as dots, lines, or comb teeth so that the brightness of the molded product is constant regardless of the location of the light source. It may be printed with a pattern. Further, a known light reflecting sheet may be laminated if necessary. The thermoplastic resin composition of the present invention can be used not only for liquid crystal display applications such as light guide plates, light diffusing sheets / films and light reflecting sheets / films, but also for light diffusion purposes such as lighting covers and signboards.

[0019]

Hereinafter, embodiments of the present invention will be described.
The present invention is not limited by this. In addition,
In the examples, parts and% are based on weight unless otherwise specified. Reference Example (a) Production of thermoplastic norbornene-based resin (a) -18-Methyl-8-methoxycarbonyltetracyclo [4.4.0.1 ^2,5 . 1 ^7,10 ] dodeca-3-en 10
2. 0 g, 1,2-dimethoxyethane 60 g, cyclohexane 240 g, 1-hexene 9 g, and a solution of diethylaluminum chloride 0.96 mol / l in toluene 3.
4 ml was added to an autoclave having an internal volume of 1 liter. On the other hand, in another flask, a solution of tungsten hexachloride (0.1%) was added.
20 ml of a 05 mol / l 1,2-dimethoxyethane solution
And 10 ml of a 0.1 mol / l 1,2-dimethoxyethane solution of paraaldehyde were mixed. This mixed solution 4.9
ml was added to the mixture in the autoclave. After sealing, the mixture was heated to 80 ° C. and stirred for 4 hours.
To the obtained polymer solution, a mixed solvent of 1/8 (weight ratio) of 1,2-dimethoxyethane and cyclohexane was added to make the polymer / solvent 1/10 (weight ratio), and then triethanolamine 20 g Was added and stirred for 10 minutes. To this polymerization solution, 500 g of methanol was added, stirred for 30 minutes and allowed to stand. The upper layer separated into two layers was removed, methanol was added again, and the mixture was stirred and allowed to stand, and then the upper layer was removed. The same operation was repeated twice, and the resulting lower layer was mixed with cyclohexane and 1,
Dilute appropriately with 2-dimethoxyethane to give a polymer concentration of 10
% Cyclohexane-1,2-dimethoxyethane solution was obtained. To this solution, 20 g of palladium / silica magnesia [manufactured by JGC Chemical Co., Ltd., palladium amount = 5%] was added, and the mixture was reacted in an autoclave at a hydrogen pressure of 40 kg / cm ² at 165 ° C. for 4 hours, and then a hydrogenation catalyst. Was removed by filtration to obtain a hydrogenated polymer solution. In addition, the hydrogenated polymer solution was mixed with pentaerythrityl-
Tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] was added to the hydrogenated polymer in an amount of 0.1%, and the solvent was removed under reduced pressure at 360 ° C. . Then, the molten resin was pelletized by an extruder in an atmosphere of nitrogen to obtain a weight average molecular weight of 7.0 × 10 ⁴ ,
A thermoplastic resin (a) -1 having a hydrogenation rate of 99.5% and a glass transition temperature of 168 ° C. was obtained. (A) -2 6-ethylidene-2-tetracyclododecene was added to (a)
After the metathesis ring-opening polymerization as in the case of -1, hydrogenation was carried out,
Pelletization was performed to obtain a thermoplastic norbornene-based resin (a) -2 having a weight average molecular weight of 5.5 × 10 ⁴ , a hydrogenation rate of 99.5%, and a glass transition temperature of 140 ° C.

(B) Light diffusing agent (b) -1 (production of crosslinked polymer particles): styrene 18
Parts by weight, 80 parts by weight of methyl methacrylate, 2 parts by weight of methacrylic acid, 12 parts by weight of t-dodecyl mercaptan, 0.05 part by weight of sodium dodecylbenzenesulfonate,
0.4 parts by weight of potassium persulfate and 200 parts by weight of water were placed in a flask having a capacity of 2 liters, and the temperature was raised to 70 ° C. in nitrogen gas with stirring to carry out polymerization for 6 hours. As a result, seed polymer particles A having a polymerization yield of 98%, an average particle diameter of 0.45 μm, and a standard deviation value of the particle diameter of 0.015 μm were obtained. Here, the particle diameter is an average value of values measured for 100 polymer particles by a transmission electron microscope photograph. The seed polymer particles A had a toluene-soluble content of 98%, and a molecular weight measured by gel permeation chromatography was weight average molecular weight (Mw) = 4,50.
0 and the number average molecular weight (Mn) = 2,900. Next, 8 parts by weight of seed polymer particles A (as solid content), 0.2 parts by weight of sodium lauryl sulfate, 0.5 parts by weight of sodium persulfate, 500 parts by weight of water, 82 parts by weight of methyl methacrylate, and 18 parts by weight of divinylbenzene. The parts were mixed and stirred at 30 ° C. for 10 minutes to allow the seed polymer particles to absorb the monomer. Next, this was heated to 70 ° C. and polymerized for 3 hours, and the polymerization yield was 99%. In addition, in the reaction product, the polymerized coagulation remaining on the 200-mesh filter was 0.02% (relative to the polymerized solid content), and the average particle size was 1.10μ with high polymerization stability.
Spherical crosslinked polymer particles (b) -1 having m, n _D ²⁵ = 1.58 were obtained. The crosslinked polymer particles (b) -1
As a result of evaluation of heat resistance by differential thermal analysis in a nitrogen gas atmosphere, when heated at a temperature rising rate of 10 ° C./minute, it was not melted or softened from room temperature to 400 ° C. (B) -2: Silica powder “Clisterlite 5X” (average particle size 7 μm, manufactured by Tatsumori Co., Ltd.) was used.

Example 1 Thermoplastic norbornene resin ((a) obtained in Reference Example
-1) 5 parts of crosslinked polymer particles (b) -1 in 100 parts by weight
Parts by weight were added and mixed at a temperature of 280 ° C. using a 40 m / m extruder to produce a pellet-shaped thermoplastic resin composition. Using this thermoplastic resin composition, a resin temperature of 320
Injection molding at a mold temperature of 130 ° C. to obtain a flat plate having a thickness of 1 mm. About this flat plate, total light transmittance, light diffusion,
Frontal brightness, heat deformability and moisture resistance were evaluated. Table 1 shows the evaluation results. In addition, each measurement was performed as follows. Total light transmittance (%) Measurement was performed according to JIS K 7105. Light diffusiveness (cm) It was represented by the shortest distance at which the lamp shape of the fluorescent lamp placed on the back surface of the molded product disappeared. Front brightness (cd / m ² ) According to JIS C 7641, a light receiver is installed in front of the film, and a cold cathode tube is used as a light source: CDK-130 manufactured by TDK.
It was measured using 1. Thermal Deformability The appearance change of the molded product after being placed in an air oven at 120 ° C. for 24 hours was visually observed, and the thermal deformability was evaluated according to the following evaluation criteria. ○: No deformation such as warpage was observed at all ×: Deformation such as warpage was noticeable Moisture resistance The following evaluation was made based on the appearance of the molded product after holding for 1000 hours under the conditions of 80 ° C and 90% relative humidity. Moisture resistance was evaluated according to the standard. ◯: No deformation such as warpage and uniform emission of light ×: Some deformation such as warpage is unusable

Example 2 A thermoplastic resin composition was produced in the same manner as in Example 1 except that the thermoplastic norbornene resin (a) -1 was used in place of the thermoplastic norbornene resin (a) -1. A flat plate was molded in the same manner as in Example 1 and evaluated. Table 1 shows the evaluation results. Example 3 A thermoplastic resin composition was produced in the same manner as in Example 1 except that the crosslinked polymer particles (b) -2 were used in place of the crosslinked polymer particles (b) -1. Was molded and evaluated. Table 1 shows the evaluation results.

Comparative Example 1 A thermoplastic resin composition was produced in the same manner as in Example 1 except that the blending amount of the crosslinked polymer particles (b) -1 was 0.05 part by weight. Was molded and evaluated. Table 1 shows the evaluation results. Comparative Example 2 A thermoplastic resin composition was produced in the same manner as in Example 1 except that the blending amount of the crosslinked polymer particles (b) -1 was 200 parts by weight, and a flat plate was molded in the same manner as in Example 1 and evaluated. I went. Table 1 shows the evaluation results. Comparative Example 3 Instead of the thermoplastic norbornene-based resin (a) -1, a polymethylmethacrylate resin (PMMA) (trade name "Acrypet VH" manufactured by Mitsubishi Rayon Co., Ltd.) was used, the resin temperature was 230 ° C, and the mold temperature was Example 1 except 100 ° C.
A thermoplastic resin composition was produced in the same manner as in Example 1, and a flat plate was formed and evaluated in the same manner as in Example 1. Table 1 shows the evaluation results.

[0024]

As is clear from Table 1, the thermoplastic resin compositions of the present invention (Examples 1 to 3) are molded products having an excellent balance of transparency and light diffusivity, and also excellent heat resistance and moisture resistance. To give. On the other hand, when the blending amount of the crosslinked polymer particles (b) is too small (Comparative Example 1), the light diffusivity is not sufficient, and it cannot be used for the purpose of light diffusion. In addition, an excessively large amount of the crosslinked polymer particles (b) (Comparative Example 2) has poor transparency. The one using PMMA as the transparent base resin (Comparative Example 3) is largely deformed by heat and humidity, and its application range and use conditions are limited. Example 4 The thermoplastic resin composition of Example 1 was used and 270
The plate was extruded at 330C and 330C to obtain a plate having a thickness of 1 mm. When this plate was evaluated in the same manner as in Example 1, the total light transmittance was 86%, the light diffusivity was 1.9 cm, and the front luminance was 14
It was 7 cd / m ² and was excellent in light diffusion. In addition, when the heat deformability and moisture resistance were evaluated, it was excellent in durability without deformation under high temperature and high humidity.

[0026]

INDUSTRIAL APPLICABILITY The thermoplastic resin composition of the present invention provides a molded article which is excellent in durability under high temperature and high humidity and has excellent light diffusivity, and therefore is used in a wide range of applications for the purpose of light diffusion. can do.

Claims (2)

[Claims] 1. A thermoplastic norbornene resin (a) 10
A thermoplastic resin composition comprising 0 parts by weight and 0.1 to 100 parts by weight of a light diffusing agent (b) having an average particle size of 0.1 to 50 μm. 2. The thermoplastic resin composition according to claim 1, wherein the light diffusing agent is crosslinked polymer particles.