WO2016190560A1 - Light diffusing powder and preparation method therefor - Google Patents

Abstract

A light diffusing powder of the present invention comprises: a polystyrene-based resin; and polyorganosilsesquioxane particles having an average diameter (D50) of approximately 0.1-0.9 μm. The light diffusing powder has an excellent light diffusion property and brightness, and a preparation method therefor reduces the loss of polyorganosilsesquioxane microparticles of approximately 0.5 μm or less and has excellent economic efficiency and processability.

Description

Light Diffusion Powder and Manufacturing Method Thereof

The present invention relates to a light diffusing powder and a method of manufacturing the same. More specifically, the present invention relates to a light diffusing powder applied to a light diffusing plate and a manufacturing method thereof.

Silicone-based fine particles such as silica and polyorganosilsesquioxane generally have excellent compatibility with various polymer resins and organic materials, and are used as additives for paints, plastics, rubbers, papers, coating liquids, and active agents to improve driving stability of high-definition video tapes. It is used in various ways.

Particularly, the polyorganosilsesquioxane particles have a three-dimensional network structure, but have excellent fluidity and compatibility with resins and have an optically low refractive index. It has been spotlighted as an apparatus backlight, a (light) diffuser of a light diffusion plate, an additive of a light guide plate, and the like.

Such polyorganosilsesquioxane particles are variously produced by a sol-gel method comprising a hydrolysis reaction and a condensation reaction mechanism using a methyltrialkoxysilane monomer as in the method disclosed in JP-A-2000-186148.

In addition, in order to apply the polyorgano silsesquioxane particles to the light diffusion plate as a diffusing agent, the powdered polyorgano silsesquioxane particles are first prepared from a thermoplastic resin such as styrene resin and a master batch composition. In addition, a method of manufacturing a light diffusion plate by mixing and extruding it with a separate thermoplastic resin is used. However, the polyorganosilsesquioxane fine particles having a particle diameter of about 0.5 μm or less may be mostly lost in the powdering process (dehydration process, etc.) of the polyorganosilsesquioxane particles, and the method powders the diffusing agent, There is a problem that the process is complicated, such as to prepare a master batch composition containing a high concentration thereof.

Accordingly, the present inventors have minimized the loss of polyorganosilsesquioxane particles having a particle diameter of about 0.5 μm or less, to prepare a light diffusion powder capable of realizing excellent light diffusibility and brightness, and to simplify process to improve processability. It is early to develop the invention.

The problem to be solved by the present invention is to provide a light diffusion powder capable of realizing excellent light diffusion and brightness.

Another object of the present invention is to provide a method for producing a light-diffusion powder capable of minimizing the loss of polyorganosilsesquioxane particles having a particle diameter of about 0.5 μm or less.

Another problem to be solved by the present invention is to provide a method for producing a light-diffusion powder excellent in economics and fairness.

Another object of the present invention is to provide a light diffusion plate to which the light diffusion powder is applied.

The above and other objects of the present invention can be achieved by the present invention described below.

One aspect of the invention relates to optical acid powder. The light diffusion powder is a polystyrene resin; And polyorganosilsesquioxane particles having an average particle diameter (D50) of about 0.1 to about 0.9 μm.

In embodiments, the polyorganosilsesquioxane particles may be included in about 0.1 to about 45 parts by weight based on about 100 parts by weight of the polystyrene-based resin.

In an embodiment, the polystyrene-based resin may be a continuous phase, and the polyorganosilsesquioxane particles may be a dispersed phase.

In embodiments, the polyorganosilsesquioxane particles may comprise from about 30 to about 99.9% by weight of the total polyorganosilsesquioxane particles of the fine particles having a particle diameter of about 0.05 to about 0.5 ㎛.

In embodiments, the light diffusing powder may have a spherical shape having a particle diameter of about 0.01 to about 10 mm or a granule shape having a long diameter of about 0.01 to about 10 mm.

In embodiments, the light diffusion powder may further include a light stabilizer.

In embodiments, the light stabilizer may include one or more of benzotriazole-based compound and triazine-based compound.

In some embodiments, the light stabilizer is a dispersed phase and may be included in an amount of about 0.1 to about 45 parts by weight based on about 100 parts by weight of the polystyrene resin.

Another aspect of the invention relates to a method for producing a light diffusing powder. The preparation method includes mixing a styrene monomer with a polymerization solution (suspension) containing polyorganosilsesquioxane particles having an average particle diameter (D50) of about 0.1 to about 0.9 μm; And polymerizing the styrene-based monomer to prepare a light diffusion powder, wherein the light diffusion powder comprises the polyorganosilsesquioxane particles and the polystyrene resin.

In an embodiment, the polyorganosilsesquioxane polymer solution may be prepared by hydrolysis and condensation of an organoalkoxy silane through a sol-gel process.

In an embodiment, an optical stabilizer may be further added when the polyorganosilsesquioxane polymer solution and a styrene monomer are mixed.

In an embodiment, dewatering the light diffusing powder; And it may further comprise the step of drying the dehydrated light diffusion powder.

In embodiments, the light diffusion powder may be about 5% by weight or less after dehydration.

Another aspect of the invention relates to a light diffusion plate manufactured using the light diffusion powder.

The present invention can minimize the loss of the light-diffusion powder that can implement excellent light diffusivity and brightness, the polyorganosilsesquioxane fine particles having a particle diameter of about 0.5 ㎛ or less, and the manufacturing method of the light-diffusion powder with excellent economic efficiency and processability It has the effect of providing the light diffusion plate to which the light diffusion powder is applied.

Hereinafter, the present invention will be described in detail.

Light diffusion powder according to the present invention is a polystyrene resin; And polyorganosilsesquioxane particles having an average particle diameter (D50) of about 0.1 to about 0.9 μm.

The polystyrene resin used in the present invention can be used without limitation the polystyrene resin used in a conventional light diffusion plate, it can be obtained by polymerizing a styrene monomer through a known polymerization method.

In an embodiment, the styrene monomers include styrene, α-methylstyrene, β-methylstyrene, p-methylstyrene, pt-butylstyrene, ethylstyrene, vinylxylene, monochlorostyrene, dichlorostyrene, dibromostyrene, Vinyl naphthalene may be used, but is not limited thereto. These may be applied alone or in mixture of two or more.

In an embodiment, the polystyrene-based resin may form a continuous phase (matrix) of the light diffusion powder. For example, after mixing a polyorganosilsesquioxane suspension containing the said polyorgano silsesquioxane particle | grains mentioned later, and the said styrene monomer, and polymerizing a styrene-type monomer, the said polyorgano silsesquioxane particle (dispersed phase ) Can be obtained a polystyrene resin (continuous phase) is dispersed.

In an embodiment, the polystyrene-based resin may have a weight average molecular weight of about 5,000 to about 50,000 g / mol, for example, about 5,000 to about 30,000 g / mol, measured using gel permeation chromatography (GPC). The polyorgano silses quoxane particles (dispersed phase) may be evenly dispersed in the polystyrene resin (continuous phase) polymerized in the above range, and during diffusion plate extrusion, the light diffusion powder may be evenly distributed and distributed in the matrix.

The polyorganosilsesquioxane particles used in the present invention may act as a light diffusing agent, and the average particle diameter (D50) measured by laser scattering particle size analysis is about 0.1 to about 0.9 μm, eg For example, about 0.3 to about 0.6 μm. If the average particle diameter of the polyorganosilsesquioxane particles is less than about 0.1 μm, the permeability may increase more than the diffusivity outside the Rayleigh scattering region, and if the average particle diameter exceeds about 0.9 μm, the diffusivity And a brightness improving effect may not be obtained, and an excessive amount of the light diffusing agent may be used.

In embodiments, the polyorganosilsesquioxane particles may comprise a repeating unit of the following formula (1).

[Formula 1]

RSiO _1.5-x (OH) _x

In Formula 1, R is an alkyl group having 1 to 6 carbon atoms, a vinyl group or an aryl group, and x has a range of 0 to 1.5. For example, R may be a methyl group, an ethyl group, a phenyl group, etc., and it is preferable from an industrial viewpoint that it is a methyl group.

In embodiments, the polyorganosilsesquioxane particles may be prepared by a sol-gel process (hydrolysis and condensation reaction) using organo alkoxy silane as a monomer, but is not limited thereto.

In embodiments, the polyorganosilsesquioxane particles may comprise from about 30 to about 99.9 weight percent, such as from about 40 to about 100 weight percent of the total polyorganosilsesquioxane particles, having a particle diameter of about 0.05 to about 0.5 μm. About 99% by weight. Since the light diffusion efficiency of the polyorganosilsesquioxane particles in the above range can be excellent, and the input amount of the diffusion agent (polyorganosilsesquioxane particles) introduced into the light diffusion plate at the same transmittance can be reduced, manufacturing cost In addition to the reduction in strength, the reduction in strength and crack increase due to the decrease in compatibility between the diffusion agent and the resin can be reduced.

In an embodiment, the polyorganosilsesquioxane particles can be in the dispersed phase of the light diffusion powder. For example, a form dispersed in a polystyrene resin (continuous phase) by mixing the suspension itself with the styrene monomer and then polymerizing the styrene monomer without powdering the polyorganosilsesquioxane suspension described below. May exist.

In embodiments, the polyorganosilsesquioxane particles may be included from about 0.1 to about 45 parts by weight, for example from about 3 to about 10 parts by weight based on about 100 parts by weight of the polystyrene-based resin. In the above range, the light diffusion powder may implement excellent diffusion effects and luminance.

The light diffusion powder according to the embodiment of the present invention may further include a light stabilizer.

In embodiments, the light stabilizer may be a light stabilizer having an absorbance of at least about 0.25 AU, for example from about 0.5 to about 1.0 AU, at a wavelength of about 380 nm for a concentration of about 20 mg / L in toluene. The optical acid powder prepared in the above range can sufficiently absorb light at wavelengths of about 380 to about 390 nm in external light, and can improve external light stability of the display device by lowering transmittance.

In embodiments, the light stabilizer may include one or more of benzotriazole-based compound and triazine-based compound, may be used commercially available light stabilizer. Specifically, light stabilizers such as Tinuvin-770, Tinuvin-P, Tinuvin-477, Tinuvin-326, etc. may be used, but are not limited thereto.

In embodiments, the light stabilizer may be in a form (disperse phase) dispersed in the polystyrene-based resin (continuous phase, matrix). For example, the light stabilizer and the polyorganosilsesquioxane suspension to be described later and the styrene monomers are mixed, and then a styrene monomer is polymerized to form the polyorganosilsesquioxane in the polystyrene resin (continuous phase, matrix). A light-diffusion powder in which particles (dispersed phase) and light stabilizer (dispersed phase) are dispersed can be obtained.

In embodiments, about 0.1 to about 45 parts by weight, for example about 0.5 to about 30 parts by weight, specifically about 1 to about 20 parts by weight, based on about 100 parts by weight of the polystyrene resin. In the above range, the transmittance of about 1% or less may be secured at a wavelength of about 380 to about 390 nm to increase external light stability, and an excessive amount of light stabilizer may be included to reduce precipitation of white spots.

The light diffusing powder according to the embodiment of the present invention has a spherical particle diameter of about 0.01 to about 10 mm, for example, about 0.03 to about 5 mm, specifically about 0.03 to about 1 mm, or a long diameter of about 0.01 to about 10 mm. mm, for example about 0.1 to about 5 mm, specifically about 0.1 to about 1 mm. In addition, when the light-diffusion powder is granular, the ratio of the long diameter and the short diameter (long diameter: short diameter) may be about 4: about 1 to about 1: about 1, for example, about 2: about 1 to about 1.5: about 1 have. In the above range, the light diffusion powder may implement excellent diffusion effects and luminance.

In the method for preparing a light diffusing powder according to an embodiment of the present invention, a polymerization solution (suspension) containing a polyorganosilsesquioxane particle having an average particle diameter (D50) of about 0.1 to about 0.9 μm is mixed with a styrene monomer. and; And preparing a light diffusion powder by polymerizing the styrene-based monomer.

Methods of preparing the polyorganosilsesquioxane polymer solution (suspension, latex) are well known to those skilled in the art. For example, the polyorganosilsesquioxane polymer solution may be prepared by a sol-gel method using an organoalkoxysilane as a monomer. More specifically, the polyorganosilsesquioxane polymerization liquid can be manufactured by hydrolyzing and condensing organotrialkoxysilane in the presence of an acid or a base catalyst in an aqueous phase.

In embodiments, the organotrialkoxysilane may be represented by the following formula (2).

[Formula 2]

RSi (OR ¹ ) ₃

In Chemical Formula 2, R is as defined in Chemical Formula 1, and R ¹ is an alkyl group having 1 to 5 carbon atoms. For example, R may be a methyl group, an ethyl group, a phenyl group, or the like, and R ¹ may be a methyl group, an ethyl group, a propyl group, or a butyl group. Specifically, it is preferable from an industrial point of view that R ¹ and R ² are methyl groups.

In an embodiment, the sol-gel process (hydrolysis and condensation reactions) is commonly known to those skilled in the art. Specifically, the hydrolysis and condensation reaction may be performed by mixing a monomer containing an organoalkoxysilane with a predetermined solvent, and may further include a catalyst to control the reaction rate. The catalyst may be an acid catalyst such as hydrochloric acid, acetic acid, hydrogen fluoride, nitric acid, sulfuric acid, chlorosulfonic acid and iodic acid; Base catalysts such as ammonia, potassium hydroxide, sodium hydroxide, barium hydroxide and imidazole; And the like can be used. More specifically, using a base catalyst, it can be carried out at a pH of about 8.5 to about 13, for example pH about 10 to about 13 conditions. In the above range, a polyorganosilsesquioxane polymer solution containing polyorganosilsesquioxane particles having an average particle diameter (D50) of about 0.1 to about 0.9 μm may be obtained. The hydrolysis and condensation reaction may be performed at room temperature for about 1 to about 24 hours, and may be performed at about 60 to about 100 ° C. for about 1 to about 8 hours to promote the reaction, but is not limited thereto. The solvent in the hydrolysis and condensation reaction is not particularly limited. For example, water, methanol, ethanol, propanol, isopropanol, n-butanol, tert-butanol, methoxypropanol and the like may be used alone or in combination of two or more thereof.

In an embodiment, the polyorganosilsesquioxane polymer solution (suspension) may be used by adding water to facilitate polymerization of the styrene monomer. In this case, the weight ratio of the polyorganosilsesquioxane particles and water may be about 0.02: about 1 to about 0.9: about 1, but is not limited thereto.

Next, the polyorganosilsesquioxane polymerization liquid (suspension) is mixed with the styrene monomer, and then the styrene monomer is polymerized to form a light diffusion powder having a polyorgano silsesquioxane dispersed in a polystyrene resin. It can manufacture. As described above, in the case where the polyorganosilsesquioxane suspension is polymerized without pulverizing, the step of preparing the conventionally powdered polyorganosilsesquioxane particles from the polystyrene resin and the master batch composition can be omitted. Therefore, the processability can be improved, and the polyorganosilsesquioxane fine particles of about 0.5 μm or less lost due to powdering can also contribute to the light diffusion effect, thereby ensuring excellent economic efficiency and light diffusion.

Polymerization of the styrene monomers is commonly known to those skilled in the art. For example, a known suspension polymerization method can be used. Specifically, a styrene-based monomer and, if necessary, a polymerization initiator, a chain transfer agent, etc. may be added, and this may be added to an aqueous solution in which a dispersion stabilizer or the like is dissolved to perform suspension polymerization. In the present invention, a styrene-based monomer or the like may be added to the polyorganosilsesquioxane suspension and mixed, and suspension polymerization may be performed. In the suspension polymerization, the polymerization temperature and the polymerization time can be appropriately adjusted. For example, the reaction may be performed at a polymerization temperature of about 65 to about 125 ° C, specifically about 70 to about 120 ° C for about 1 to about 8 hours, but is not limited thereto.

In embodiments, the polymerization initiator may be used a conventional radical polymerization initiator known in the polymerization art, for example, potassium persulfate, octanoyl peroxide, decanyl peroxide, lauroyl peroxide, benzoyl peroxide Monochlorobenzoyl peroxide, dichlorobenzoyl peroxide, p-methylbenzoyl peroxide, tert-butyl perbenzoate, azobisisobutyronitrile and azobis- (2,4-dimethyl) -valeronitrile and the like can be used. May be, but is not limited thereto. The polymerization initiator may be applied alone or by mixing two or more kinds. The polymerization initiator may include about 0.01 to about 10 parts by weight, for example about 0.03 to about 5 parts by weight, based on about 100 parts by weight of the styrene-based polymer, but is not limited thereto.

In one embodiment, the above-described light stabilizer may be further added when the polyorganosilsesquioxane suspension and the styrene monomer are mixed. In this case, a light-diffusion powder in which the polyorganosilsesquioxane particles (dispersed phase) and the light stabilizer (dispersed phase) are dispersed in a polystyrene resin (continuous phase, matrix) prepared from a styrene monomer can be obtained.

In one embodiment, to obtain the powdered light diffusing powder, a dehydration process of the light diffusing powder may be performed. The dewatering process is purified by the centrifugal separator, filter press, vibrating screen (vibrating screen), etc. after the first dewatered sludge after washing with water, about 60 to about 200 ℃, for example about 70 to about 90 The light-diffusing powder in the form of a white powder may be prepared by drying using a fluidized bed dryer, a spin flash dryer, a vacuum dryer, a convection oven, or the like within a range of ° C. The powdered light diffusing powder may have a water content of about 5% by weight or less, for example, about 3 to about 5% by weight.

The light diffusing plate according to the present invention is prepared using the light diffusing powder. When the light diffusion powder of the present invention is applied to the light diffusion plate production, it is possible to implement excellent brightness and light diffusion, the light diffusion plate is particularly useful as a diffusion plate used in LCD-TV.

In some embodiments, the light diffusion plate may include about 100 parts by weight of the thermoplastic resin and about 0.1 to about 10 parts by weight of the light diffusion powder, for example, about 0.5 to about 8 parts by weight. In the above range, the transmittance of the thermoplastic resin may be reduced to be suitable as the diffusion plate, and the luminance, light diffusing property, and light resistance may be excellent.

In an embodiment, the thermoplastic resin may be a vinyl chloride resin, a polystyrene resin, a styrene-acrylonitrile resin, a polyacrylic resin, an acrylic-styrene resin, a polyester resin, or an ABS resin, which is used in a conventional diffusion plate. Resin or polycarbonate resin can be used without limitation.

The method of manufacturing such a light diffusion plate can be easily carried out by those skilled in the art. For example, after mixing the thermoplastic resin and the light diffusing powder and other additives as necessary, melt extrusion in the extruder to produce a pellet form, and various molding such as injection molding, extrusion molding, vacuum molding, casting molding Through the method, it can be manufactured into various light diffusing plates (molded articles).

Hereinafter, the configuration and operation of the present invention through the preferred embodiment of the present invention will be described in more detail. However, the following examples are provided to help the understanding of the present invention, and the scope of the present invention is not limited to the following examples. Details that are not described herein will be omitted since those skilled in the art can sufficiently infer technically.

Example

Production Example  One: Light diffusion  Preparation of Powder

240 g of methyltrimethoxysilane was added to 1,760 g of ion-exchanged water, stirred for 30 minutes, pH was adjusted to 9.6 by addition of ammonia water, and left to stand for 4 hours to prepare a polymethylsilsesquioxane polymer solution (suspension). Prepared. Here, the average particle diameter (D50) of the polymethylsilsesquioxane particles in the polymethylsilsesquioxane polymer solution measured by laser scattering particle size analysis was 0.3 μm, and the content of the fine particles below 0.5 μm was 99 μm. It was%. After mixing 50 parts by weight of the prepared polymethylsilsesquioxane polymerization solution and 50 parts by weight of ion-exchanged water, 10 parts by weight of the styrene monomer, 0.1 parts by weight of the polymerization initiator (potassium sulfate) and light stabilizer, Ciba's Tinuvin-770 and Tinuvin 3 parts by weight of -P were each added and stirred for 30 minutes to prepare a mixed droplet. If necessary, after adding 0.025 parts by weight of tricalcium phosphate dissolved in 2.5 parts by weight of ion-exchanged water, the temperature was maintained at 75 to 95 ° C. for about 5 hours to complete the reaction. In order to powder the obtained light-diffusion powder (polymer), a dehydration process was performed and then dried at 80 ° C. for 12 hours to obtain powdered light-diffusion powder (yield: 98% or more). The prepared light-diffusion powder has a weight ratio (PS: PMSQ) of 100: 3.36 of polystyrene resin and polymethylsilsesquioxane particles, and has a spherical particle diameter of 0.1 to 2 mm measured by laser scattering particle size analysis. And a granule shape having a long diameter of 0.5 to 5 mm.

Example  One

100 parts by weight of polystyrene resin (weight average molecular weight: 340,000 g / mol) and 24.5 parts by weight of the light-diffusion powder of Preparation Example 1 were mixed and extruded in a twin screw extruder having Φ = 45 mm to prepare pellets, and using a 10 oz injection machine. , 1.5 mm thick plate specimens were manufactured at a molding temperature of 240 ° C., and the transmittance (transmittance of light, TT) and haze were measured according to the following physical property measurement method, and the results are shown in Table 1 below.

Example  2

A flat plate specimen was manufactured in the same manner as in Example 1, except that 30 parts by weight of the light diffusing powder of Preparation Example 1 was used. The transmittance and the haze were measured, and the results are shown in Table 1 below.

Example  3

A flat plate specimen was manufactured in the same manner as in Example 1, except that 40 parts by weight of the light diffusing powder of Preparation Example 1 was used. The transmittance and the haze were measured, and the results are shown in Table 1 below.

Comparative example  One

100 parts by weight of polystyrene resin (weight average molecular weight: 340,000 g / mol), polymethylsilsesquioxane particles (manufacturer: Samsung SDI, product name: SL-100M, average particle diameter (D50): 1 μm, average particle diameter (D50) 0.5 15 parts by weight of the microparticles and the like or less and 50 parts by weight and 5 parts by weight of Ciba Tinuvin-770 and Tinuvin-P (weight ratio 1: 1) were respectively mixed with a light stabilizer to form a master batch composition. Next, 100 parts by weight of polystyrene resin (weight average molecular weight: 340,000 g / mol) and 15 parts by weight of the master batch composition were mixed and extruded in a twin screw extruder having Φ = 45 mm to prepare pellets, and using a 10 oz injection machine, A flat plate specimen having a thickness of 1.5 mm was prepared at a molding temperature of 240 ° C., and the transmittance (transmittance of light, TT) and haze were measured according to the following physical property measurement method, and the results are shown in Table 1 below.

Comparative example  2

Except that 20 parts by weight of the master batch composition was used to prepare a flat plate specimen in the same manner as in Comparative Example 1, transmittance and haze were measured, and the results are shown in Table 1 below.

Property evaluation method

(1) Transmittance (TT) (unit:%): It measured using the haze meter (NDH 5000W, Nippon Denshi Kogyo Co., Ltd.).

(2) Haze (unit:%): It measured using the haze meter (NDH 5000W, Nippon Denshi Kogyo Co., Ltd.).

Example 1 Example 2 Example 3 Comparative Example 1 Comparative Example 2 Polystyrene resin 100 100 100 100 100 Light Diffusion Powder 24.5 30 40 - - Masterbatch composition - - - 15 20 PMSQ Particle Average Particle Size (D50) 0.3 μm 0.3 μm 0.3 μm 1 μm 1 μm PMSQ Particle Content in Specimens (wt%) 0.796 0.975 1.3 1.5 2.0 Transmittance (%) 61.1 62.1 61.1 64.57 60.1 Haze (%) 92.1 92.8 91.8 91.2 86.4

(Unit: parts by weight)

From the results of Table 1, the specimen using the light-diffusion powder of the present invention, including the polymethylsilsesquioxane particles having an average particle diameter of 0.3 ㎛, even if containing a small amount of 1.3% by weight, the diffusion performance is excellent Able to know.

On the other hand, Comparative Examples 1 and 2 using polyorganosilsesquioxane particles having an average particle diameter (D50) of 1.0 μm exhibited low diffusion performance due to high transmittance or low haze, even when an excessive amount was used. Able to know.

Simple modifications or changes of the present invention can be easily carried out by those skilled in the art, and all such modifications or changes can be seen to be included in the scope of the present invention.

Claims (14)

Polystyrene resin; And Light-diffusion powder, characterized in that it comprises polyorganosilsesquioxane particles having an average particle diameter (D50) of about 0.1 to about 0.9 μm. The light diffusing powder of claim 1, wherein the polyorganosilsesquioxane particles are included in an amount of about 0.1 to about 45 parts by weight based on about 100 parts by weight of the polystyrene-based resin. The light diffusing powder of claim 1, wherein the polystyrene-based resin is a continuous phase and the polyorganosilsesquioxane particles are a dispersed phase. The polyorganosilsesquioxane particles according to claim 1, wherein the polyorganosilsesquioxane particles comprise fine particles having a particle diameter of about 0.05 to about 0.5 μm in about 30 to about 99.9 wt% of 100 wt% of the total polyorganosilsesquioxane particles. Light Diffusion Powder. The light diffusing powder of claim 1, wherein the light diffusing powder has a spherical particle size of about 0.01 to about 10 mm, or a granule shape having a long diameter of about 0.01 to about 10 mm. The light diffusing powder of claim 1, wherein the light diffusing powder further comprises a light stabilizer. The light diffusing powder according to claim 6, wherein the light stabilizer comprises at least one of a benzotriazole compound and a triazine compound. The light diffusing powder of claim 6, wherein the light stabilizer is in a dispersed phase and is included in an amount of about 0.1 to about 45 parts by weight based on about 100 parts by weight of the polystyrene resin. Mixing a styrene monomer with a polymerization solution (suspension) containing polyorganosilsesquioxane particles having an average particle diameter (D50) of about 0.1 to about 0.9 μm; And And polymerizing the styrene-based monomers to prepare a light diffusion powder. The light diffusion powder is a method for producing a light diffusion powder, characterized in that containing the polyorganosilsesquioxane particles and polystyrene resin. The method of claim 9, wherein the polyorganosilsesquioxane polymer is prepared by hydrolyzing and condensing an organoalkoxy silane through a sol-gel process. 10. The method of claim 9, wherein a light stabilizer is further added when the polyorganosilsesquioxane polymer solution and a styrene monomer are mixed. 10. The method of claim 9, further comprising: dehydrating the light diffusing powder; And drying the dehydrated light-diffusing powder. The method of claim 12, wherein the light diffusing powder has a water content of about 5% by weight or less after dehydration. A light diffusing plate manufactured using the light diffusing powder according to any one of claims 1 to 8.