JP4890766B2 - Light diffusing aromatic polycarbonate resin composition - Google Patents

Description

  The present invention relates to a light diffusing aromatic polycarbonate resin composition. More specifically, the present invention relates to a light diffusing aromatic polycarbonate resin composition having high light diffusibility and exhibiting high luminance when used in a light diffusion plate for direct type backlight.

  For applications that require light diffusibility, such as various lighting covers, light diffusion plates for transmissive displays, diffusion plates for automobile meters, and various nameplates, aromatic polycarbonate resin, acrylic resin, styrene resin, and chloride A material in which an organic or inorganic light diffusing agent is dispersed in a transparent resin such as vinyl resin is widely used. Among such transparent resins, aromatic polycarbonate resins are widely used because they are excellent in mechanical properties, heat resistance, and weather resistance, and have high light transmittance.

  Examples of the light diffusing agent include organic particles having a crosslinked structure such as crosslinked acrylic particles, crosslinked silicone particles, and crosslinked styrene particles. As light diffusing agents, inorganic particles such as calcium carbonate, barium sulfate, aluminum hydroxide, silicon dioxide, titanium oxide, and calcium fluoride, or inorganic fibers such as short glass fibers are also used. In particular, organic particles are excellent in surface smoothness of molded products as compared with inorganic particles and can achieve a high appearance of molded products, and therefore can be applied to a wide range of applications.

  Examples of the use of the material in which the light diffusing agent is dispersed include, for example, an electric light cover, a meter, a signboard (especially internally lit) in a polycarbonate resin, a resin window glass, an image reading device, and a light diffusing plate for a display device ( Examples thereof include a light diffusing plate used for a backlight module in a liquid crystal display device and a light diffusing plate used for a screen of a projection display device such as a projector television. A molded article made of a light diffusing aromatic polycarbonate resin composition is advantageous in that it has a good light diffusing function and is excellent in heat resistance and dimensional stability as compared with a conventional acrylic resin.

  In any of the above applications, more uniform and high light transmittance is required. In particular, a light diffusion plate used for a backlight module, particularly a light diffusion plate used for a direct type backlight module in which light sources are arranged directly opposite the light diffusion plate, requires uniform and high luminance. ing. The light diffusing aromatic polycarbonate resin composition is suitable for a larger liquid crystal display device due to the above-mentioned characteristics, but such a larger device is required to have higher luminance.

  It was formed from an aromatic polycarbonate resin composition comprising an aromatic polycarbonate resin, polymer fine particles represented by polymethylsilsesquioxane, a heat stabilizer excluding a hindered phenol compound, an ultraviolet absorber, and an optical brightener. A light diffusing plate for a direct type backlight is known (see Patent Document 1). Furthermore, in this document, the reason why a light diffusing plate with good luminance is obtained is that the composition of the resin composition suppresses the alteration of the aromatic polycarbonate due to the thermal stability of the polymer fine particles, and in particular a specific stability. In the use of the agent, it is presumed to suppress light absorption by the stabilizer. However, it has been difficult to say that this document sufficiently discloses a further improvement in luminance.

  On the other hand, various methods are known as a method for producing polyorganosilsesquioxane particles. A method for polycondensation of an organosilane triol obtained by hydrolyzing an organotrialkoxysilane in the presence of an organic acid or a partial condensate thereof in an alkaline aqueous solution or a mixed solution of the aqueous solution and an organic solvent is known. Yes (see Patent Document 2). Such particles have a minute particle size and the particle size distribution is monodisperse.

  In producing polyorganosilsesquioxane particles by hydrolyzing and condensing organotrialkoxysilane and / or a partial hydrolysis-condensation product thereof in a reaction solution, a polymer dispersant such as polyvinyl alcohol is added to the reaction solution. The manufacturing method to make it exist is well-known (refer patent document 3). This invention is characterized in that fine particles having a uniform particle diameter are efficiently produced at a high concentration.

WO04 / 111169 pamphlet Japanese Patent Laid-Open No. 1-217039 JP 2003-342370 A

  An object of the present invention is a light diffusing aromatic polycarbonate resin composition having high light diffusibility and light transmittance, excellent in hue of a molded product, and exhibiting high luminance particularly when installed in a direct type backlight module. To provide things. As a result of intensive studies to achieve the above object, the present inventor has obtained a light diffusing aromatic polycarbonate resin containing an aromatic polycarbonate resin and polyorganosilsesquioxane particles having a weight reduction starting temperature in a specific temperature range. The present inventors have found that the composition is excellent in the hue of an injection-molded or extruded molded product, and have reached the present invention.

  According to the present invention, the object of the present invention is (1) (A) 100 parts by weight of an aromatic polycarbonate resin (component A), and (B) 1% by weight in thermogravimetry (TGA) according to JIS K7120. This is achieved by a light diffusing aromatic polycarbonate resin composition comprising 0.005 to 20 parts by weight of polyorganosilsesquioxane particles (component B) having a decreasing temperature of 400 to 500 ° C. That is, the gist of the present invention is that polyorganosilsesquioxane particles having a much higher weight loss temperature than before are blended in an aromatic polycarbonate resin, and as a result, the above-mentioned problems have been achieved. A typical example of polyorganosilsesquioxane particles conventionally used in light-diffusing aromatic polycarbonate resin compositions is Tospearl 120 (trade name, manufactured by GE Toshiba Silicone Co., Ltd.). Compared to the 1% weight loss temperature of such Tospearl 120 of 345 ° C., that of the polyorganosilsesquioxane particles of the present invention is much higher. Another advantage of the present invention is that the resin composition is improved by utilizing conventionally used polyorganosilsesquioxane particles and improving them. This means that practically important conditions and know-how for manufacturing molded articles that have been accumulated in the past and knowledge about the cause of defects can be used effectively.

  It is inferred that the cause of the difference in luminance due to the characteristics of polyorganosilsesquioxane is the amount of alkoxy groups remaining that cannot undergo the condensation reaction. It is considered that such alkoxy groups cause a side reaction with the polycarbonate resin during melt processing, thereby adversely affecting the amount of transmitted light, hue, and luminance. On the other hand, since polyorganosilsesquioxane is a crosslinked structure insoluble in a solvent, it is difficult to easily perform a detailed analysis, and the amount of remaining alkoxy groups is very small. Therefore, it can be said that the TGA 1% weight loss temperature is a useful index for specifying polyorganosilsesquioxane. The TGA 1% weight loss temperature in the present invention is measured according to JIS K7120, using a TGA measuring device, in a nitrogen gas atmosphere, a temperature range from 23 ° C. to 900 ° C., and a temperature increase of 20 ° C./min. Made under measurement conditions consisting of speed. In such weight reduction behavior, the temperature at which 1% weight reduction is observed is defined as the TGA 1% weight reduction temperature.

  One of the preferred embodiments of the present invention is (2) the light diffusing aromatic polycarbonate resin composition having the constitution (1), wherein the component B is polymethylsilsesquioxane particles.

  One preferred embodiment of the present invention is that (3) phosphorus stabilizer (component C) 0.0001 to 1 part by weight, and / or (3) 100 parts by weight of component A aromatic polycarbonate resin, and / or Or (D) It is a light diffusable aromatic polycarbonate resin composition of the said structure (1)-(2) formed by mix | blending 0.001-1 weight part of hindered phenolic compounds (D component).

  By blending such a stabilizer, the thermal stability of the aromatic polycarbonate resin itself is improved, and a light diffusing aromatic polycarbonate resin composition having further excellent luminance is provided. The C component and the D component can be blended singly or in combination of two or more. In particular, the C component is preferably contained as an essential component.

  One of the preferred embodiments of the present invention is that (4) 100 parts by weight of the A component aromatic polycarbonate resin and (E) fluorescent brightener (component E) 0.0005 to 0.5 parts by weight and (F) The light-diffusing aromatic polycarbonate resin composition having the constitution (1) to (3), wherein 0.001 to 0.5 parts by weight of an ultraviolet absorber (F component) is blended.

  By blending such components, a light diffusing aromatic polycarbonate resin composition with improved luminance or less hue change during its long-term use is provided. E component and F component can be blended singly or in combination of two or more. In particular, it is preferable to mix E component and F component together with C component.

  One preferred embodiment of the present invention is (5) a light diffusing plate formed from the light diffusing aromatic polycarbonate resin composition having the constitutions (1) to (4). A more preferred embodiment is (6) a light diffusing plate for direct type backlight formed from the light diffusing aromatic polycarbonate resin composition having the constitutions (1) to (4). The light diffusing aromatic polycarbonate resin composition of the present invention can be particularly suitably used for a light diffusion plate for direct type backlight.

Details of the present invention will be described below.
<About component A>
The A component of the present invention is an aromatic polycarbonate resin that is a main component of the resin composition. A typical aromatic polycarbonate resin (hereinafter, sometimes simply referred to as “polycarbonate”) is obtained by reacting a dihydric phenol and a carbonate precursor, and as a reaction method, an interfacial polycondensation method, Examples thereof include a melt transesterification method, a solid phase transesterification method of a carbonate prepolymer, and a ring-opening polymerization method of a cyclic carbonate compound.

  Specific examples of the dihydric phenol include hydroquinone, resorcinol, 4,4′-biphenol, 1,1-bis (4-hydroxyphenyl) ethane, 2,2-bis (4-hydroxyphenyl) propane (commonly referred to as “bisphenol”). A ″), 2,2-bis (4-hydroxy-3-methylphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 1,1-bis (4-hydroxyphenyl) -1-phenylethane 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 2,2-bis (4-hydroxyphenyl) pentane, 4, 4 ′-(p-phenylenediisopropylidene) diphenol, 4,4 ′-(m-phenylenediisopropylidene) Phenol, 1,1-bis (4-hydroxyphenyl) -4-isopropylcyclohexane, bis (4-hydroxyphenyl) oxide, bis (4-hydroxyphenyl) sulfide, bis (4-hydroxyphenyl) sulfoxide, bis (4- Hydroxyphenyl) sulfone, bis (4-hydroxyphenyl) ketone, bis (4-hydroxyphenyl) ester, 2,2-bis (3,5-dibromo-4-hydroxyphenyl) propane, bis (3,5-dibromo- 4-hydroxyphenyl) sulfone, bis (4-hydroxy-3-methylphenyl) sulfide, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, etc. Is mentioned. Among these, bis (4-hydroxyphenyl) alkane, especially bisphenol A (hereinafter sometimes abbreviated as “BPA”) is widely used.

  In the present invention, in addition to the general-purpose polycarbonate bisphenol A-based polycarbonate, a special polycarbonate produced using other dihydric phenols can be used as the A component.

  For example, as part or all of the dihydric phenol component, 4,4 ′-(m-phenylenediisopropylidene) diphenol (hereinafter sometimes abbreviated as “BPM”), 1,1-bis (4-hydroxy Phenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane (hereinafter sometimes abbreviated as “Bis-TMC”), 9,9-bis (4-hydroxyphenyl) Polycarbonate (homopolymer or copolymer) using fluorene and 9,9-bis (4-hydroxy-3-methylphenyl) fluorene (hereinafter sometimes abbreviated as “BCF”) has dimensions due to water absorption. It is suitable for applications where the demands for change and shape stability are particularly severe. These dihydric phenols other than BPA are preferably used in an amount of 5 mol% or more, particularly 10 mol% or more of the entire dihydric phenol component constituting the polycarbonate.

In particular, when high rigidity and better hydrolysis resistance are required, it is particularly preferable that the component A constituting the resin composition is a copolymerized polycarbonate of the following (1) to (3). is there.
(1) BPM is 20 to 80 mol% (more preferably 40 to 75 mol%, more preferably 45 to 65 mol%) in 100 mol% of the dihydric phenol component constituting the polycarbonate, and BCF Of 20 to 80 mol% (more preferably 25 to 60 mol%, more preferably 35 to 55 mol%).
(2) BPA is 10 to 95 mol% (more preferably 50 to 90 mol%, more preferably 60 to 85 mol%) in 100 mol% of the dihydric phenol component constituting the polycarbonate, and BCF Is 5 to 90 mol% (more preferably 10 to 50 mol%, more preferably 15 to 40 mol%).
(3) BPM is 20 to 80 mol% (more preferably 40 to 75 mol%, more preferably 45 to 65 mol%) in 100 mol% of the dihydric phenol component constituting the polycarbonate, and Bis -Copolymer polycarbonate in which TMC is 20 to 80 mol% (more preferably 25 to 60 mol%, still more preferably 35 to 55 mol%).

  These special polycarbonates may be used alone or in combination of two or more. Moreover, these can also be mixed and used for the bisphenol A type polycarbonate generally used.

  The production method and characteristics of these special polycarbonates are described in detail in, for example, JP-A-6-172508, JP-A-8-27370, JP-A-2001-55435, and JP-A-2002-117580. ing.

Of the various polycarbonates described above, those having a water absorption and Tg (glass transition temperature) adjusted within the following ranges by adjusting the copolymer composition, etc. have good hydrolysis resistance of the polymer itself, and Since it is remarkably excellent in low warpage after molding, it is particularly suitable in a field where form stability is required.
(I) polycarbonate having a water absorption of 0.05 to 0.15%, preferably 0.06 to 0.13% and Tg of 120 to 180 ° C, or (ii) Tg of 160 to 250 ° C, Polycarbonate which is preferably 170 to 230 ° C. and has a water absorption of 0.10 to 0.30%, preferably 0.13 to 0.30%, more preferably 0.14 to 0.27%.

  Here, the water absorption of the polycarbonate is a value obtained by measuring the moisture content after being immersed in water at 23 ° C. for 24 hours in accordance with ISO 62-1980 using a disc-shaped test piece having a diameter of 45 mm and a thickness of 3.0 mm. is there. Moreover, Tg (glass transition temperature) is a value calculated | required by the differential scanning calorimeter (DSC) measurement based on JISK7121.

  On the other hand, carbonyl halide, carbonate ester, haloformate, or the like is used as the carbonate precursor, and specific examples include phosgene, diphenyl carbonate, dihaloformate of dihydric phenol, and the like.

  In producing a polycarbonate from such a dihydric phenol and a carbonate precursor by an interfacial polymerization method, a catalyst, a terminal terminator, and an antioxidant for preventing the dihydric phenol from being oxidized as necessary. Etc. may be used. The polycarbonate may be a branched polycarbonate copolymerized with a trifunctional or higher polyfunctional aromatic compound. Examples of the trifunctional or higher polyfunctional aromatic compound used here include 1,1,1-tris (4-hydroxyphenyl) ethane, 1,1,1-tris (3,5-dimethyl-4-hydroxy). Phenyl) ethane and the like.

When a polyfunctional compound that produces a branched polycarbonate is included, the amount thereof is 0.001 to 1 mol%, preferably 0.005 to 0.9 mol%, particularly preferably 0.01 to 0.8 mol, based on the total amount of the polycarbonate. Mol%. In particular, in the case of the melt transesterification method, a branched structure may occur as a side reaction. The amount of the branched structure is also 0.001 to 1 mol%, preferably 0.005 to 0.9% in the total amount of the polycarbonate. Those having a mol%, particularly preferably 0.01 to 0.8 mol% are preferred. The ratio of the branched structure can be calculated by ¹ H-NMR measurement.

  Further, the polycarbonate of the present invention is a polyester carbonate obtained by copolymerizing an aromatic or aliphatic (including alicyclic) bifunctional carboxylic acid, and a copolymer obtained by copolymerizing a bifunctional alcohol (including alicyclic). Polycarbonate and polyester carbonate obtained by copolymerizing such a bifunctional carboxylic acid and a bifunctional alcohol may also be used. Moreover, the mixture which blended 2 or more types of the obtained polycarbonate may be used.

  The aliphatic bifunctional carboxylic acid used here is preferably an α, ω-dicarboxylic acid. Examples of the aliphatic bifunctional carboxylic acid include, for example, sebacic acid (decanedioic acid), dodecanedioic acid, tetradecanedioic acid, octadecanedioic acid, icosanedioic acid and the like, and saturated aliphatic dicarboxylic acid and cyclohexanedicarboxylic acid. Preferred are alicyclic dicarboxylic acids such as As the bifunctional alcohol, an alicyclic diol is more preferable, and examples thereof include cyclohexanedimethanol, cyclohexanediol, and tricyclodecane dimethanol.

Furthermore, in the present invention, a polycarbonate-polyorganosiloxane copolymer obtained by copolymerizing polyorganosiloxane units can be used as the component A.
The component A polycarbonate may be a mixture of two or more of polycarbonates such as polycarbonates having different dihydric phenols, polycarbonates containing branched components, polyester carbonates, and polycarbonate-polyorganosiloxane copolymers. . Furthermore, what mixed 2 or more types of polycarbonates from which a manufacturing method differs, a polycarbonate from which a terminal terminator differs, etc. can also be used.

  In the polycarbonate polymerization reaction, the reaction by the interfacial polycondensation method is usually a reaction between a dihydric phenol and phosgene, and is carried out in the presence of an acid binder and an organic solvent. As the acid binder, for example, an alkali metal hydroxide such as sodium hydroxide or potassium hydroxide or an amine compound such as pyridine is used. As the organic solvent, for example, halogenated hydrocarbons such as methylene chloride and chlorobenzene are used. In order to accelerate the reaction, for example, a catalyst such as a tertiary amine such as triethylamine, tetra-n-butylammonium bromide, or tetra-n-butylphosphonium bromide, a quaternary ammonium compound, or a quaternary phosphonium compound can be used. . At that time, the reaction temperature is usually 0 to 40 ° C., the reaction time is preferably about 10 minutes to 5 hours, and the pH during the reaction is preferably maintained at 9 or more.

  In such a polymerization reaction, a terminal terminator is usually used. Monofunctional phenols can be used as such end terminators. As the monofunctional phenols, for example, monofunctional phenols such as phenol, p-tert-butylphenol, and p-cumylphenol are preferably used. Furthermore, as monofunctional phenols, long chain alkyl groups having 10 or more carbon atoms such as decylphenol, dodecylphenol, tetradecylphenol, hexadecylphenol, octadecylphenol, eicosylphenol, docosylphenol and triacontylphenol. A monofunctional phenol substituted with a nucleus can be mentioned, and the phenol is effective in improving fluidity and hydrolysis resistance. Such end terminators may be used alone or in combination of two or more.

The reaction by the melt transesterification method is usually a transesterification reaction between a dihydric phenol and a carbonate ester, and the alcohol or alcohol produced by mixing the dihydric phenol and the carbonate ester with heating in the presence of an inert gas. It is carried out by a method of distilling phenol. The reaction temperature varies depending on the boiling point of the alcohol or phenol produced, but in most cases is in the range of 120 to 350 ° C. In the latter stage of the reaction, the reaction system is decompressed to about 1.33 × 10 ^{3 to} 13.3 Pa to facilitate the distillation of the alcohol or phenol produced. The reaction time is usually about 1 to 4 hours.

  Examples of the carbonate ester include esters such as an aryl group having 6 to 10 carbon atoms, an aralkyl group, or an alkyl group having 1 to 4 carbon atoms, which may have a substituent, and among them, diphenyl carbonate is preferable.

A polymerization catalyst can be used to increase the polymerization rate. Examples of the polymerization catalyst include alkali metal compounds such as sodium hydroxide, potassium hydroxide, sodium salt and potassium salt of dihydric phenol; alkaline earth metal compounds such as calcium hydroxide, barium hydroxide and magnesium hydroxide; Nitrogen-containing basic compounds such as methylammonium hydroxide, tetraethylammonium hydroxide, trimethylamine, and triethylamine can be used. Further, alkali (earth) metal alkoxides, alkali (earth) metal organic acid salts, boron compounds, germanium compounds, antimony compounds, titanium compounds, zirconium compounds, etc., esterification reaction, transesterification The catalyst used for the reaction can be used. These catalysts may be used alone or in combination of two or more. The amount of the catalyst used is preferably selected in the range of 1 × 10 ⁻⁹ to 1 × 10 ⁻⁵ equivalents, more preferably 1 × 10 ^{−8 to} 5 × 10 ⁻⁶ equivalents, relative to 1 mol of dihydric phenol as a raw material. It is.

  In the reaction by the melt transesterification method, for example, 2-chlorophenylphenyl carbonate, 2-methoxycarbonylphenylphenyl carbonate, 2-ethoxycarbonyl is used at the later stage or after completion of the polycondensation reaction for the purpose of reducing the phenolic end groups of the produced polycarbonate. Compounds such as phenylphenyl carbonate can be added.

  Furthermore, in the melt transesterification method, it is preferable to use a deactivator that neutralizes the activity of the catalyst. The amount of the deactivator is preferably 0.5 to 50 mol with respect to 1 mol of the remaining catalyst. Moreover, it is suitable to use in the ratio of 0.01-500 ppm with respect to the polycarbonate after superposition | polymerization, More preferably, it is 0.01-300 ppm, Most preferably, it is a ratio of 0.01-100 ppm. Examples of preferable quenching agents include phosphonium salts such as tetrabutylphosphonium dodecylbenzenesulfonate and ammonium salts such as tetraethylammonium dodecylbenzyl sulfate.

  The viscosity average molecular weight of the aromatic polycarbonate resin of component A is not limited. However, when the viscosity average molecular weight is less than 10,000, the strength and the like are lowered, and when it exceeds 50,000, the molding process characteristics are lowered. Therefore, the range of 10,000 to 50,000 is preferable. The range of 15,000 to 30,000 is more preferable, and the range of 15,000 to 28,000 is more preferable. In this case, it is also possible to mix a polycarbonate having a viscosity average molecular weight outside the above range within the range in which the moldability and the like are maintained. For example, a high molecular weight polycarbonate component having a viscosity average molecular weight exceeding 50,000 can be blended.

The viscosity average molecular weight referred to in the present invention is first determined by using an Ostwald viscometer from a solution obtained by dissolving 0.7 g of aromatic polycarbonate in 100 ml of methylene chloride at 20 ° C. with a specific viscosity (η _SP ) calculated by the following formula. ,
Specific viscosity (η _SP ) = (t−t ₀ ) / t ₀
[T ₀ is methylene chloride falling seconds, t is sample solution falling seconds]
The viscosity average molecular weight M is calculated from the determined specific viscosity (η _SP ) by the following formula.
η _SP /c=[η]+0.45×[η] ² c (where [η] is the intrinsic viscosity)
[Η] = 1.23 × 10 ⁻⁴ M ^0.83
c = 0.7

  In addition, calculation of the viscosity average molecular weight in the light diffusable aromatic polycarbonate resin composition which uses A component is performed in the following way. That is, the composition is mixed with 20 to 30 times its weight of methylene chloride to dissolve the soluble component in the composition. Such soluble matter is collected by Celite filtration. Thereafter, the solvent in the obtained solution is removed. The solid after removal of the solvent is sufficiently dried to obtain a solid component that dissolves in methylene chloride. A specific viscosity at 20 ° C. is determined from a solution obtained by dissolving 0.7 g of the solid in 100 ml of methylene chloride in the same manner as described above, and the viscosity average molecular weight M is calculated from the specific viscosity in the same manner as described above.

<About B component>
The B component of the present invention is polyorganosilsesquioxane particles having a 1% weight loss temperature of 400 to 500 ° C. in thermogravimetry (TGA) according to JIS K7120. The lower limit of the weight loss temperature is preferably 430 ° C, more preferably 450 ° C, and particularly preferably 460 ° C. The upper limit of the preferred weight loss temperature is 490 ° C.

  The production method of the polyorganosilsesquioxane of component B is not particularly limited as long as the TGA 1% weight loss temperature condition is satisfied. In general, polyorganosilsesquioxane is produced by hydrolytic condensation of an organoalkoxysilane. In such a condensation reaction, the reaction conditions are appropriately adjusted so that the remaining alkoxy groups are reduced, that is, the degree of condensation is increased, while the desired particle size is obtained.

  A commonly used method for producing polyorganosilsesquioxane particles is a method in which an organoalkoxysilane and an aqueous ammonia solution are reacted at a stirring speed capable of maintaining a two-phase interface. However, in such a method, if the reaction is activated by raising the pH in order to increase the degree of condensation, the resulting particle size tends to be small. As a result, a particle size effective as light diffusion particles cannot be obtained. That is, for effective particle size, the pH in the reaction system must be lowered, and as a result, it is difficult to further reduce the remaining alkoxy groups.

  Accordingly, among the methods for producing the component B by hydrolytic condensation of organoalkoxysilane, a more preferable method is to hydrolyze the alkoxysilane portion once to form silanol, thereby substantially eliminating the alkoxy group, and then taking this. In this method, an alkali is added to silanol to cause a hydrolytic condensation reaction. That is, in this method, an organoalkoxysilane is hydrolyzed in the presence of an acid such as an organic acid, and the resulting organosilanol or a hydrolysis condensate thereof is dissolved in an alkaline aqueous solution or a mixed solution of the aqueous solution and an organic solvent. This is a method of polycondensation reaction (referred to as method-1). Details of such a production method are described, for example, in JP-A-1-217039, and a method for producing particles having a more preferable particle diameter is described in, for example, JP-A-10-45914. The particle size can be adjusted mainly by adjusting the pH of the aqueous alkali solution. The particle diameter can be controlled by increasing the pH if small particles are to be obtained, and by decreasing the pH if large particles are to be obtained. By adding an alkali in the reaction solution, the condensation reaction proceeds in the range of pH 7.6 to 13, preferably 9.7 to 12. The condensation reaction is usually carried out in the range of 0.5 to 10 hours, preferably 0.5 to 5 hours after alkali addition, and the condensate is aged. Such ripening is preferably performed under weak stirring or standing in order to prevent the association of particles.

  The acid in Method-1 may be either an organic acid or an inorganic acid, but is preferably an organic acid. Examples of the organic acid include formic acid, acetic acid, oxalic acid, and citric acid. Examples of the alkaline substance used in the aqueous alkaline solution include alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, ammonia, and organic amines such as monomethylamine and dimethylamine. Among them, ammonia is preferable. The organic solvent in Method-1 is preferably a water-soluble one, and examples thereof include alcohols such as methanol and ethanol, glycols such as ethylene glycol, ethers such as acetone and diethyl ether, and tetrahydrofuran.

When the component B of the present invention is produced by hydrolytic condensation of organoalkoxysilane, a surfactant may be contained in the reaction solution. As such a surfactant, a nonionic surfactant is particularly preferable. Furthermore, when manufacturing B component by hydrolytic condensation of organoalkoxysilane, water-soluble polymers, such as polyvinyl alcohol and polyvinylpyrrolidone, can be contained. Such a polymer can efficiently suppress aggregation of the polyorganosilsesquioxane particles produced by the protective colloid effect, and can increase the reaction rate and the particle concentration. As a result, polyorganosilsesquioxane particles can be produced more efficiently. The degree of polymerization of such a polymer is preferably in the range of 100 to 3,000, more preferably 200 to 1,500. The amount of the polymer added in the reaction solution is preferably in the range of 5 × 10 ^{−5 to} 5% by weight, more preferably in the range of 0.005 to 0.5% by weight.

  When the component B is produced by hydrolytic condensation of organoalkoxysilane, the temperature of the reaction solution can be selected from the range of 0 ° C. which is the freezing point of water to 100 ° C. which is the boiling point of water at normal pressure. Although it is possible at 100 ° C. or higher, it is preferably in the range of 15 to 80 ° C. The reaction is preferably carried out at normal pressure. The produced polyorganosilsesquioxane particles are then separated by filtration and washed with water or organic solvent. Thereafter, an acidic substance is further added for neutralization, followed by separation by filtration, washing with water or organic solvent, and drying. The obtained particles can be used as they are, or further pulverized to obtain particles.

The average particle size of the component B is preferably 0.1 to 20 μm, more preferably 0.3 to 6 μm, and still more preferably 1 to 3 μm. The average particle diameter is represented by a 50% value (D ₅₀ ) of the cumulative distribution of particle sizes obtained by the laser diffraction / scattering method. The particle size distribution may be single or plural. That is, it is possible to combine two or more light diffusing agents having different average particle diameters. However, a more preferred light diffusing agent has a narrow particle size distribution. The variation coefficient represented by “particle diameter standard deviation σ / average particle diameter D × 100 (%)” is preferably within 20%, more preferably within 10%, and even more preferably within 7%. An appropriate lower limit is 1%. The shape of the light diffusing agent is preferably close to a sphere from the viewpoint of light diffusibility, and more preferably a shape close to a true sphere. More nearly spherical means more specifically a shape having a ratio of major axis to minor axis within 1.1. Such a spherical shape includes an elliptical sphere.

The polyorganosilsesquioxane particles of the present invention have 1 to 4 trifunctional siloxane units (hereinafter simply referred to as “T units”) represented by R—SiO _3/2 (R is a monovalent organic group). What is 90 mol% or more out of a total of 100 mol% of functional siloxane units. The proportion of T units is more preferably 95 mol% or more, and still more preferably substantially 100 mol%.

  Examples of the organic group bonded to the polyorganosilsesquioxane include aryl groups such as alkyl groups having 1 to 18 carbon atoms, phenyl groups, tolyl groups, and xylyl groups, β-phenylethyl groups, and β-phenylpropyl groups. Examples include an aralkyl group and a cyclohexyl group. Furthermore, a reactive group represented by a vinyl group, a γ-glycidoxypropyl group, a γ-methacryloxypropyl group, and the like can also be contained.

  Examples of the alkyl group having 1 to 18 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, decyl group, dodecyl group, and octadecyl group. Is done. More preferably, the alkyl group is an alkyl group having 1 to 12 carbon atoms, more preferably 1 to 10 carbon atoms. A methyl group is particularly preferred.

  Accordingly, when the component B of the present invention is produced by hydrolytic condensation of organoalkoxysilane, alkyltrialkoxysilane is preferred as the organoalkoxysilane, and methyltrimethoxysilane is particularly preferred. Two or more organic groups bonded to the polyorganosilsesquioxane can be used in combination. Further, by performing multi-stage condensation, the component B can also have a multilayer structure formed by condensation of different organoalkoxysilanes.

<Content of component B>
Content of B component is 0.005-20 weight part on the basis of 100 weight part A component, Preferably it is 0.01-10 weight part, Most preferably, it is 0.1-5 weight part. If it is less than 0.005 parts by weight, sufficient light diffusibility cannot be obtained, and if it exceeds 20 parts by weight, the light transmittance becomes insufficient, such being undesirable.

<About component C>
The C component of the present invention is various phosphorus stabilizers. The main purpose of blending such a phosphorus stabilizer is to improve the thermal stability during molding of the resin composition and to obtain diffuse light having a good hue. Examples of such phosphorus stabilizers include phosphorous acid, phosphoric acid, phosphonous acid, phosphonic acid and esters thereof, and tertiary phosphine.

  Specifically, as the phosphite compound, for example, triphenyl phosphite, tris (nonylphenyl) phosphite, tridecyl phosphite, trioctyl phosphite, trioctadecyl phosphite, didecyl monophenyl phosphite, dioctyl monophenyl Phosphite, diisopropyl monophenyl phosphite, monobutyl diphenyl phosphite, monodecyl diphenyl phosphite, monooctyl diphenyl phosphite, 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, tris ( Diethylphenyl) phosphite, tris (di-iso-propylphenyl) phosphite, tris (di-n-butylphenyl) phosphite, tris (2,4-di-tert-butylpheny) ) Phosphite, tris (2,6-di-tert-butylphenyl) phosphite, distearyl pentaerythritol diphosphite, bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite, bis (2 , 6-Di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, bis (2,6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, bis {2,4-bis (1-methyl-1-phenylethyl) phenyl} pentaerythritol diphosphite, phenylbisphenol A pentaerythritol diphosphite, bis (nonylphenyl) pentaerythritol diphosphite, dicyclohexyl pentaerythritol diphosphite, etc. And the like.

  Further, as other phosphite compounds, those which react with dihydric phenols and have a cyclic structure can be used. For example, 2,2′-methylenebis (4,6-di-tert-butylphenyl) (2,4-di-tert-butylphenyl) phosphite, 2,2′-methylenebis (4,6-di-tert- Examples include butylphenyl) (2-tert-butyl-4-methylphenyl) phosphite, 2,2′-methylenebis (4-methyl-6-tert-butylphenyl) octyl phosphite, and the like.

  Examples of the phosphate compound include tributyl phosphate, trimethyl phosphate, tricresyl phosphate, triphenyl phosphate, trichlorophenyl phosphate, triethyl phosphate, diphenyl cresyl phosphate, diphenyl monoorxenyl phosphate, tributoxyethyl phosphate, dibutyl phosphate, dioctyl phosphate, And diisopropyl phosphate are exemplified, and triphenyl phosphate and trimethyl phosphate are preferable.

  Examples of the phosphonite compound include tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite, tetrakis (2,4-di-tert-butylphenyl) -4,3′-biphenylenedi. Phosphonite, tetrakis (2,4-di-tert-butylphenyl) -3,3′-biphenylenediphosphonite, tetrakis (2,6-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite Tetrakis (2,6-di-tert-butylphenyl) -4,3′-biphenylene diphosphonite, tetrakis (2,6-di-tert-butylphenyl) -3,3′-biphenylene diphosphonite, bis (2,4-di-tert-butylphenyl) -4-phenyl-phenylphosphonite, bis (2,4-di tert-butylphenyl) -3-phenyl-phenylphosphonite, bis (2,6-di-n-butylphenyl) -3-phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl)- 4-phenyl-phenylphosphonite, bis (2,6-di-tert-butylphenyl) -3-phenyl-phenylphosphonite, and the like, and tetrakis (di-tert-butylphenyl) -biphenylenediphosphonite, Bis (di-tert-butylphenyl) -phenyl-phenylphosphonite is preferred, tetrakis (2,4-di-tert-butylphenyl) -biphenylenediphosphonite, and bis (2,4-di-tert-butylphenyl) ) -Phenyl-phenylphosphonite is more preferred. Such a phosphonite compound is preferable because it can be used in combination with a phosphite compound having an aryl group in which two or more alkyl groups are substituted.

  Examples of the phosphonate compound include dimethyl benzenephosphonate, diethyl benzenephosphonate, and dipropyl benzenephosphonate.

  Tertiary phosphine includes triethylphosphine, tripropylphosphine, tributylphosphine, trioctylphosphine, triamylphosphine, dimethylphenylphosphine, dibutylphenylphosphine, diphenylmethylphosphine, diphenyloctylphosphine, triphenylphosphine, tri-p-tolyl. Examples include phosphine, trinaphthylphosphine, and diphenylbenzylphosphine. A particularly preferred tertiary phosphine is triphenylphosphine.

  The phosphorus stabilizer can be used not only in one kind but also in a mixture of two or more kinds. Among the phosphorus stabilizers, phosphite compounds or phosphonite compounds are preferable. The most preferred phosphite compound is tris (2,4-di-tert-butylphenyl) phosphite. Examples of the phosphonite compound include tetrakis (2,4-di-tert-butylphenyl) -4,4′-biphenylenediphosphonite and bis (2,4-di-tert-butylphenyl) -phenyl-phenylphosphonite and these And a mixture of these is most preferable. The weight ratio between the two (the former / the latter) is preferably in the range of 90/10 to 70/30, more preferably in the range of 85/15 to 75/25. A combination of these and a phosphate compound is also a preferred embodiment.

  The amount of component C is preferably 0.0001 to 1 part by weight, more preferably 0.01 to 1 part by weight, still more preferably 0.02 to 0, based on 100 parts by weight of component A. .5 parts by weight. If it is less than 0.0001 part by weight, the resistance to melting discoloration cannot be obtained, and if it exceeds 1 part by weight, the light diffusing aromatic polycarbonate resin composition of the present invention will be altered.

<About D component>
The D component of the present invention is a hindered phenol stabilizer. The main purpose of blending such a hindered phenol stabilizer is to improve the heat stability, heat aging resistance, and ultraviolet resistance during molding of the light diffusing resin composition. Examples of such hindered phenol-based stabilizers include α-tocopherol, butylhydroxytoluene, sinapyl alcohol, vitamin E, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate, 2 -Tert-butyl-6- (3'-tert-butyl-5'-methyl-2'-hydroxybenzyl) -4-methylphenyl acrylate, 2,6-di-tert-butyl-4- (N, N- Dimethylaminomethyl) phenol, 3,5-di-tert-butyl-4-hydroxybenzylphosphonate diethyl ester, 2,2′-methylenebis (4-methyl-6-tert-butylphenol), 2,2′-methylenebis (4 -Ethyl-6-tert-butylphenol), 4,4'-methylenebis (2, -Di-tert-butylphenol), 2,2'-methylenebis (4-methyl-6-cyclohexylphenol), 2,2'-dimethylene-bis (6-α-methyl-benzyl-p-cresol) 2,2 ' -Ethylidene-bis (4,6-di-tert-butylphenol), 2,2'-butylidene-bis (4-methyl-6-tert-butylphenol), 4,4'-butylidenebis (3-methyl-6-tert) -Butylphenol), triethylene glycol-N-bis-3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionate, 1,6-hexanediol bis [3- (3,5-di- tert-butyl-4-hydroxyphenyl) propionate], bis [2-tert-butyl-4-methyl 6- (3-tert-butyl) Ru-5-methyl-2-hydroxybenzyl) phenyl] terephthalate, 3,9-bis {2- [3- (3-tert-butyl-4-hydroxy-5-methylphenyl) propionyloxy] -1,1, -Dimethylethyl} -2,4,8,10-tetraoxaspiro [5,5] undecane, 4,4'-thiobis (6-tert-butyl-m-cresol), 4,4'-thiobis (3- Methyl-6-tert-butylphenol), 2,2′-thiobis (4-methyl-6-tert-butylphenol), bis (3,5-di-tert-butyl-4-hydroxybenzyl) sulfide, 4,4 ′ -Di-thiobis (2,6-di-tert-butylphenol), 4,4'-tri-thiobis (2,6-di-tert-butylphenol), 2,2-thiodie Renbis- [3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate], 2,4-bis (n-octylthio) -6- (4-hydroxy-3,5-di-tert- Butylanilino) -1,3,5-triazine, N, N′-hexamethylenebis- (3,5-di-tert-butyl-4-hydroxyhydrocinnamide), N, N′-bis [3- (3 , 5-Di-tert-butyl-4-hydroxyphenyl) propionyl] hydrazine, 1,1,3-tris (2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl -2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, tris (3,5-di-tert-butyl-4-hydroxyphenyl) iso Cyanurate, tris (3,5-di-tert-butyl-4-hydroxybenzyl) isocyanurate, 1,3,5-tris (4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl) isocyanurate, 1,3,5-tris2 [3 (3,5-di-tert-butyl-4-hydroxyphenyl) propionyloxy] ethyl isocyanurate and tetrakis [methylene-3- (3,5-di-tert-butyl -4-hydroxyphenyl) propionate] methane and the like. Among these, octadecyl-3- (3,5-di-tert-butyl-4-hydroxyphenyl) propionate (CIBA SPECILITY CHEMICALS: Irganox 1076 (trade name)) is preferable as a typical commercial product. All of the above-mentioned hindered phenolic antioxidants are easily available, and these can be used alone or in combination of two or more.

  The amount of component D is preferably 0.001 to 1 part by weight based on 100 parts by weight of component A, more preferably 0.005 to 0.8 part by weight, and still more preferably 0.01 to 0.0 part by weight. 5 parts by weight. If the blending amount is less than 0.001 part by weight, no resistance to melting or dry heat discoloration can be obtained, and if it exceeds 1 part by weight, the luminance decreases.

<About E component>
The E component of the present invention is an optical brightener. The main purpose of such fluorescent whitening agents is to improve the brightness of the diffused light and to adjust the hue of the diffused light. The fluorescent whitening agent has an action of absorbing energy in the ultraviolet part of light and radiating this energy to the visible part. As the optical brightener, known bisbenzoxazole, coumarin, bis (styryl) biphenyl, and the like can be used. Of these, coumarin fluorescent whitening agents are preferred. Examples of the coumarin fluorescent whitening agent include triazine-phenylcoumarin, benzotriazole-phenylcoumarin, and naphthotriazole-phenylcoumarin. The compounding quantity of E component is 0.0005-0.5 weight part on the basis of 100 weight part A component, More preferably, it is 0.0005-0.3 weight part. Even if it exceeds 0.5 part by weight, the effect of improving the color tone of the composition is small.

<About F component>
The F component of the present invention is an ultraviolet absorber. The combination of the UV absorber is more preferable when used outdoors or when used under a strong light source. Specific examples of the ultraviolet absorber of the present invention include 2,4-dihydroxybenzophenone, 2-hydroxy-4-methoxybenzophenone, 2-hydroxy-4-octoxybenzophenone, 2-hydroxy-4-benze in benzophenone series. Roxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxybenzophenone, 2-hydroxy-4-methoxy-5-sulfoxytrihydride benzophenone, 2,2'-dihydroxy-4-methoxybenzophenone, 2,2 ' , 4,4′-tetrahydroxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxybenzophenone, 2,2′-dihydroxy-4,4′-dimethoxy-5-sodiumsulfoxybenzophenone, bis (5 -Benzoyl-4-hydroxy-2-methoxy Phenyl) methane, 2-hydroxy-4-n-dodecyloxybenzophenone, 2-hydroxy-4-methoxy-2′-carboxybenzophenone and the like, and in the benzotriazole series, 2- (2-hydroxy-5-methylphenyl) ) Benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-3,5-dicumylphenyl) phenylbenzotriazole, 2- (2-hydroxy-3-tert) -Butyl-5-methylphenyl) -5-chlorobenzotriazole, 2,2'-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) Phenol], 2- (2-hydroxy-3,5-di-tert-butylphenyl) ben Triazole, 2- (2-hydroxy-3,5-di-tert-butylphenyl) -5-chlorobenzotriazole, 2- (2-hydroxy-3,5-di-tert-amylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-octylphenyl) benzotriazole, 2- (2-hydroxy-5-tert-butylphenyl) benzotriazole, 2- (2-hydroxy-4-octoxyphenyl) benzotriazole, 2, 2'-methylenebis (4-cumyl-6-benzotriazolephenyl), 2,2'-p-phenylenebis (1,3-benzoxazin-4-one), 2- [2-hydroxy-3- (3 4,5,6-tetrahydrophthalimidomethyl) -5-methylphenyl] benzotriazole, Cyclic imino ester ultraviolet absorbers such as 2,2′-p-phenylenebis (3,1-benzoxazin-4-one), 1,3-bis-[(2′-cyano-3 ′, 3′- Cyanoacrylate-based UV absorbers such as diphenylacryloyl) oxy] -2,2-bis [(2-cyano-3,3-diphenylacryloyl) oxy] methyl) propane, and triazine-based UV absorbers. Polymers from ultraviolet absorbing monomers may be used, and these may be used alone or in combination of two or more. Such an ultraviolet absorber is preferably 0.001 to 2 parts by weight, more preferably 0.05 to 1 part by weight, based on 100 parts by weight of the component A.

<About other ingredients>
The light diffusing aromatic polycarbonate resin of the present invention can be further blended with other conventional additives within a range in which the effects of the present invention are exhibited. For example, flame retardants, light stabilizers, mold release agents, anti-dripping agents, flame retardant aids, dyes, pigments, phosphorescent pigments, fluorescent dyes other than fluorescent brighteners, antistatic agents, flow modifiers, crystal nucleating agents, Inorganic and organic antibacterial agents, photocatalytic antifouling agents (fine particle titanium oxide, fine particle zinc oxide, etc.), impact modifiers typified by graft rubber, infrared absorbers, photochromic agents, and the like can be blended.

  Flame retardant formulations are often preferred when used under stronger light sources. Examples of the flame retardant of the present invention include tetrabromobisphenol A, oligomers of tetrabromobisphenol A, brominated bisphenol epoxy resin, brominated bisphenol phenoxy resin, brominated bisphenol polycarbonate, brominated polystyrene, brominated crosslinked polystyrene, bromo Halogenated flame retardants typified by halogenated polyphenylene ether, polydibromophenylene ether, decabromodiphenyl oxide bisphenol condensate and halogenated phosphate ester; triphenyl phosphate as monophosphate compound, resorcinol bis (dixylenyl) as condensed phosphate ester Phosphate), bisphenol A bis (diphenyl phosphate), and bisphenol A bis (dixylenyl phosphate) Other organic phosphate ester flame retardants typified by pentaerythritol diphenyldiphosphate; inorganic phosphates such as ammonium polyphosphate, aluminum phosphate and zirconium phosphate; inorganic metals such as aluminum hydroxide and magnesium hydroxide Inorganic flame retardants typified by compound hydrates, zinc borate, zinc metaborate, magnesium oxide, molybdenum oxide, zirconium oxide, tin oxide, and antimony oxide; potassium perfluorobutanesulfonate, perfluorobutanesulfonic acid Organic alkenyl typified by calcium, cesium perfluorobutanesulfonate, potassium diphenylsulfone-3-sulfonate, potassium diphenylsulfone-3,3′-disulfonate, and β-naphthalenesulfonate sodium formalin condensate Li (earth) metal salt flame retardants; (poly) organosiloxane compounds containing phenyl groups, and copolymers of (poly) organosiloxanes and polycarbonate resins; phosphazenes represented by phenoxyphosphazene oligomers and cyclic phenoxyphosphazene oligomers And flame retardants.

  Examples of the flame retardant aid include sodium antimonate and antimony trioxide, and examples of the anti-dripping agent include polytetrafluoroethylene having fibril forming ability. Further, such polytetrafluoroethylene is preferably a dispersion liquid, a coating obtained by co-coagulation of the dispersion and another polymer, etc. as a form at the time of blending, and a fine dispersion form is possible. The blending amount of the flame retardant, flame retardant aid, and anti-dripping agent is preferably 0.01 to 10 parts by weight based on 100 parts by weight of component A.

  The mold release agent preferably used in the present invention is a mold release agent comprising 90% by weight or more of a monohydric alcohol and a monohydric fatty acid ester and / or a polyhydric alcohol and a fatty acid ester. Such an ester is preferably an ester of a monovalent or polyhydric alcohol having 1 to 20 carbon atoms and a saturated fatty acid having 5 to 30 carbon atoms. Such esters of monohydric or polyhydric alcohols and saturated fatty acids include stearyl stearate, palmityl palmitate, butyl stearate, methyl laurate, isopropyl palmitate, 2-ethylhexyl stearate, stearic acid monoglyceride, stearic acid triglyceride Sorbitan distearate, pentaerythritol tetrastearate, pentaerythritol tetrapelargonate, propylene glycol distearate and the like can be used alone or in a mixture of two or more. Of these, stearic acid monoglyceride, stearic acid triglyceride, stearyl stearate, and pentaerythritol tetrastearate are preferably used. When such a release agent is used, the blending amount can vary depending on the purpose, but is preferably 0.02 to 1 part by weight based on 100 parts by weight of component A.

  Further, the light diffusing aromatic polycarbonate resin composition of the present invention is typified by anthraquinone dyes, perylene dyes, coumarin dyes, thioindigo dyes, thioxanthone dyes, etc., and emits green, yellow, red, etc. , Organic dyes such as fluorescent dyes other than fluorescent brighteners, ferrocyanides such as bitumen, perinone dyes, quinoline dyes, quinacridone dyes, dioxazine dyes, isoindolinone dyes, and phthalocyanine dyes System dyes can be blended, and these are preferably 0.0001 to 2 parts by weight based on 100 parts by weight of component A.

  Examples of the light stabilizer include hindered amine-based light stabilizers. Specifically, bis (2,2,6,6-tetramethyl-4-piperidyl) sebacate, bis (1,2,2, 6,6-pentamethyl-4-piperidyl) sebacate, bis (1,2,2,6,6-pentamethyl-4-piperidyl) -2- (3,5-di-tert-butyl-4-hydroxybenzyl)- 2n-butyl malonate, condensate of 1,2,3,4-butanecarboxylic acid, 2,2,6,6-tetramethyl-4-piperidinol and tridecyl alcohol, 1,2,3,4-butane Condensation product of dicarboxylic acid, 1,2,2,6,6-pentamethyl-4-piperidinol and tridecyl alcohol, tetrakis (2,2,6,6-tetramethyl-4-piperidyl) -1,2,3 , -Butanetetracarboxylate, tetrakis (1,2,2,6,6-pentamethyl-4-piperidyl) -1,2,3,4-butanetetracarboxylate, poly {[6- (1,1,3, 3-tetramethylbutyl) amino-1,3,5-triazine-2,4-diyl] [(2,2,6,6-tetramethylpiperidyl) imino] hexamethylene [(2,2,6,6- Tetramethylpiperidyl) imino]}, poly {[6-morpholino-s-triazine-2,4-diyl] [(2,2,6,6-tetramethylpiperidyl) imino] hexamethylene [(2,2,6 , 6-tetramethylpiperidyl) imino]}, 1,2,3,4-butanetetracarboxylic acid and 2,2,6,6-tetramethyl-4-piperidinol and β, β, β ′, β′-tetra Methyl-3 , 9- (2,4,8,10-tetraoxaspiro [5,5] undecane) diethanol, N, N'-bis (3-aminopropyl) ethylenediamine and 2,4-bis [N- Condensate with butyl-N- (1,2,2,6,6-pentamethyl-4-piperidyl) amino] -chloro-1,3,5-triazine, 1,2,3,4-butanetetracarboxylic acid 1,2,2,6,6-pentamethyl-4-piperidinol and β, β, β ′, β′-tetramethyl-3,9- (2,4,8,10-tetraoxaspiro [5,5 ] Undecane) condensates with diethanol, polymethylpropyl 3-oxy- [4- (2,2,6,6-tetramethyl) piperidinyl] siloxane and the like. Such light stabilizers can be used alone or in combination of two or more.

<About the manufacturing method of a resin composition>
In producing the light diffusing aromatic polycarbonate resin composition of the present invention, the production method is not particularly limited. However, a preferred method for producing the resin composition of the present invention is a method of melt-kneading each component using an extruder. Such a method achieves good dispersion of the polyorganosilsesquioxane particles.

  A twin screw extruder is particularly suitable as the extruder. A typical example is ZSK (trade name, manufactured by Werner & Pfleiderer). In such a ZSK type twin screw extruder, the screw is a fully meshed type, and the screw includes various screw segments having different lengths and pitches, and various kneading disks having different widths (and corresponding kneading segments). It consists of

  A more preferable embodiment in the twin screw extruder is as follows. As the screw shape, one, two, and three screw screws can be used, and in particular, a two-thread screw having a wide range of application in both the ability to convey the molten resin and the shear kneading ability can be preferably used. The ratio (L / D) of the screw length (L) to the diameter (D) in the twin-screw extruder is preferably 20 to 45, more preferably 28 to 42. When L / D is large, uniform dispersion is likely to be achieved, whereas when it is too large, decomposition of the resin is likely to occur due to thermal degradation. The screw needs to have one or more kneading zones composed of kneading disk segments (or kneading segments corresponding thereto) for improving kneadability, and preferably 1 to 3 kneading zones.

  Furthermore, as an extruder, what has a vent which can deaerate the water | moisture content in a raw material and the volatile gas which generate | occur | produces from melt-kneading resin can be used preferably. From the vent, a vacuum pump is preferably installed for efficiently discharging generated moisture and volatile gas to the outside of the extruder. It is also possible to remove a foreign substance from the resin composition by installing a screen for removing the foreign substance mixed in the extrusion raw material in the zone in front of the extruder die. Examples of such a screen include a wire mesh, a screen changer, a sintered metal plate (such as a disk filter), and the like.

  Furthermore, the method for supplying the B component, C component, D component, E component, F component, and other additives (simply referred to as “additives” in the following examples) to the extruder is not particularly limited, but the following method is used. Typically exemplified. (I) A method in which the additive is fed into the extruder independently of the component A resin. (Ii) A method in which the additive and the resin powder of component A are premixed using a mixer such as a super mixer and then supplied to the extruder. (Iii) A method in which an additive and component A resin are previously melt-kneaded to form a master pellet.

  One of the methods (ii) is a method in which all necessary raw materials are premixed and supplied to the extruder. Another method (ii) is a method in which a master agent containing a high concentration of additives is prepared, and the master agent is independently or further premixed with the remaining resin and then supplied to the extruder. is there. The master agent can be selected from either a powder form or a form obtained by compressing and granulating the powder. Other premixing means include, for example, a Nauter mixer, a V-type blender, a Henschel mixer, a mechanochemical apparatus, and an extrusion mixer. A high-speed stirring type mixer such as a super mixer is preferable. Still another premixing method is, for example, a method in which a resin and an additive are uniformly dispersed in a solvent and then the solvent is removed.

  The resin extruded from the extruder is directly cut into pellets, or after forming strands, the strands are cut with a pelletizer and pelletized. Furthermore, when it is necessary to reduce the influence of external dust or the like, it is preferable to clean the atmosphere around the extruder. Furthermore, in the production of such pellets, various methods already proposed for polycarbonate resin for optical discs and cyclic polyolefin resins for optical discs are used to narrow the shape distribution of pellets, reduce miscuts, transport or transport. It is possible to appropriately reduce the fine powder that is sometimes generated and the bubbles (vacuum bubbles) generated in the strands and pellets. By these prescriptions, it is possible to increase the molding cycle and reduce the occurrence rate of defects such as silver. Moreover, although the shape of a pellet can take common shapes, such as a cylinder, a prism, and a spherical shape, it is a cylinder more suitably. The diameter of such a cylinder is preferably 1 to 5 mm, more preferably 1.5 to 4 mm, and still more preferably 2 to 3.3 mm. On the other hand, the length of the cylinder is preferably 1 to 30 mm, more preferably 2 to 5 mm, and still more preferably 2.5 to 3.5 mm.

<About a molded product comprising the resin composition of the present invention>
The light diffusing aromatic polycarbonate resin composition of the present invention obtained as described above can be usually produced by injection molding the pellets produced as described above to produce various products. Furthermore, the resin melt-kneaded by an extruder can be directly made into a sheet, a film, a profile extrusion molded product, a direct blow molded product, and an injection molded product without going through pellets.

  In such injection molding, not only a normal molding method but also an injection compression molding, an injection press molding, a gas assist injection molding, a foam molding (including those by injection of a supercritical fluid), an insert molding, depending on the purpose as appropriate. A molded product can be obtained using an injection molding method such as in-mold coating molding, heat insulating mold molding, rapid heating / cooling mold molding, two-color molding, sandwich molding, and ultrahigh-speed injection molding. The advantages of these various molding methods are already widely known. In addition, either a cold runner method or a hot runner method can be selected for molding.

  Moreover, the resin composition of this invention can also be utilized in the form of various profile extrusion-molded articles, a sheet | seat, a film, etc. by extrusion molding. For forming sheets and films, an inflation method, a calendar method, a casting method, or the like can also be used. It is also possible to form a heat-shrinkable tube by applying a specific stretching operation. The resin composition of the present invention can be formed into a molded product by rotational molding, blow molding or the like.

  Thereby, a molded article of a light diffusing aromatic polycarbonate resin composition having diffused light of excellent hue is provided. That is, according to the present invention, a light diffusing aromatic polycarbonate resin composition containing 0.005 to 20% by weight of B component and other additives based on 100 parts by weight of A component is melt-molded. A molded product is provided.

<About light diffusion plate>
The light diffusing aromatic polycarbonate resin composition of the present invention is excellent in light transmittance, hue and luminance, and also in heat stability. Therefore, it is suitable for a light diffusion plate having a large area. A more preferable application is a light diffusion plate having a surface area of 500 to 50,000 cm ² . The preferred surface area of the light diffusion plate is 1,000 to 25,000 cm ² and the preferred thickness is 0.3 to 3 mm.
Therefore, according to the present invention, there is provided a light diffusing plate comprising the above light diffusing aromatic polycarbonate resin composition, having such an area, and having excellent light transmittance, hue and luminance.

According to the present invention, further preferred mode, made from the light diffusing aromatic polycarbonate resin composition, for a display device of the area 500~50,000cm ² (more preferably 1,000~25,000cm ²⁾ A light diffusing plate is provided. Examples of the light diffusing plate for a display device include a light diffusing plate used for a backlight module of a liquid crystal display device and a light diffusing plate used for a screen of a projection display device such as a projector television. Of these, a light diffusion plate for direct type backlight is preferable. Various light sources can be used for the backlight module, and a cold cathode fluorescent lamp, a white LED, and an LED array in which three colors of red, green and blue are arranged are used.

  The surface of the light diffusing plate comprising the light diffusing aromatic polycarbonate resin composition of the present invention may have surface irregularities such as a Fresnel lens shape, a cylindrical lens shape, a bright dot shape, and a prism shape. It is also possible to make a laminated plate in which such shapes are separately laminated with other materials. When the Fresnel lens shape or the cylindrical lens shape is directly applied to the light diffusing aromatic polycarbonate resin composition of the present invention, a desired shape is obtained by a molding method such as injection molding, compression molding, and extrusion molding using the resin composition. Can be molded. Furthermore, as a method of forming irregularities on the surface by injection molding, compression molding, and extrusion molding, (1) irregularities corresponding to the shape on the mold cavity surface or transfer roll surface are provided, and the irregularities are resin molded products. A method of transferring to the surface, and (2) after another material provided with unevenness corresponding to such a shape is inserted into the mold cavity or laminated at the time of extrusion and integrated with the resin molded product, An example is a method in which the other material is removed to provide unevenness on the surface of the resin molded product.

  In some cases, such a screen can be provided with a layer containing a luster pigment to eliminate a lens due to surface irregularities. Furthermore, the light diffusing plate for a display device according to the present invention can be formed with various antireflection films for preventing reflection of light from the light source on the light source side (surface opposite to the observer).

<About other uses>
Further, the light diffusing aromatic polycarbonate resin composition of the present invention is not limited to the above-mentioned light diffusing plate, but also various electronic / electric equipment, OA equipment, exterior parts for vehicles, interior parts for vehicles, mechanical parts, and other agriculture. It is useful for various applications such as materials, fishery materials, transport containers, packaging containers and miscellaneous goods. Applications other than light diffusion plates for display devices include, for example, electric lamp covers, meters, signboards (particularly internally lit), resin window glass, image reading devices, vehicle roofing materials, ship roofing materials, and housing roofing materials. And a solar cell cover and the like.

  Furthermore, various surface treatments can be performed on the molded article made of the light diffusing aromatic polycarbonate resin composition of the present invention. Surface treatment here refers to resin molded products such as vapor deposition (physical vapor deposition, chemical vapor deposition, etc.), plating (electroplating, electroless plating, hot dipping, etc.), painting, coating, and printing (including transfer-type laminates). A new layer is formed on the surface layer, and a method usually used for resins can be applied. Specific examples of the surface treatment include various surface treatments such as hard coat, water / oil repellent coat, ultraviolet absorption coat, infrared absorption coat, and metalizing (evaporation). Hard coat is a preferred and required surface treatment for outdoor use.

  The light-diffusing aromatic polycarbonate resin composition of the present invention is a resin composition that exhibits diffused light having an excellent hue that has never been obtained before. Furthermore, since it has good thermal stability, it is used for light diffusing plates for large display devices (for example, light diffusing plates used for backlight modules such as liquid crystal display devices, screens for projection display devices such as projector televisions). It is particularly suitable as a light diffusion plate or the like. In addition to the light diffusing plate for the display device, such characteristics include, for example, an electric lamp cover, a meter, a signboard (particularly an internally lit type), a resin window glass, an image reading device, a vehicle roofing material, a vehicle interior component ( Such parts are typically vehicle interior lighting covers), ship roofing materials, residential roofing materials, solar cell covers, various electronic and electrical equipment, OA equipment, vehicle parts, machine parts, other agricultural materials, fishery It is useful in a wide range of fields including materials, transport containers, packaging containers, and miscellaneous goods, and can be said to have extremely high industrial value.

  The form of the present invention considered to be the best by the present inventor is a collection of the preferable ranges of the above requirements. For example, typical examples are described in the following examples. Of course, the present invention is not limited to these forms.

The following examples further illustrate the present invention. The evaluation was based on the following method.
(1) Hue of diffused light: The b value measured by a C light source transmission method using a color machine (Nippon Denshoku Industries Co., Ltd., Z-1001DP).
(2) Dispersion degree: A test piece having a side of 50 mm and a thickness of 2 mm was used, and the measurement was performed using a dispersion degree meter manufactured by Nippon Denshoku Industries Co., Ltd. An outline of the measurement method is shown in FIG. The dispersion degree is the angle (degree) of γ when the amount of transmitted light is 50, assuming that the amount of transmitted light is 100 when γ = 0 degree when a light beam is applied vertically from above in FIG. ) As the degree of dispersion.
(3) Average luminance: A 150 × 150 × 2 mmt test piece was incorporated in a 15-inch direct-type backlight unit, and the luminance (cd / m ² ) of 9 points of the test piece was measured with a luminance meter BM-7 manufactured by Topcon Corporation. The average value was defined as the average luminance. The outline of the evaluation apparatus is shown in FIGS.
(4) Total light transmittance: In accordance with JIS K-7361, measurement was performed with a reflection / transmittance meter HR-100 manufactured by Murakami Color Research Laboratory.
(5) TGA 1% weight loss temperature of polymethylsilsesquioxane particles: Hi-Res TGA2950 Thermographic Analyzer manufactured by TA-instruments was used, and the temperature was increased from 23 ° C. to 20 ° C./min in an N ₂ atmosphere. The temperature was raised to 0 ° C. to obtain a weight loss curve. From this data, the temperature when the weight loss of the sample became 1% by weight of the charged weight was measured as the TGA 1% weight reduction temperature.

[Examples 1-2 and Comparative Examples 1-4]
After blending various additives shown in Table 1 in 100 parts by weight of the resin at various blending amounts and mixing with a blender, a vent type twin screw extruder (manufactured by Nippon Steel Works, Ltd .: TEX30α (completely meshed, in the same direction) The mixture was melt-kneaded using a rotating, two-thread screw)) to obtain pellets. When using polycarbonate resin powder as a raw material, a pre-mixture with a polycarbonate resin powder was prepared using a Henschel mixer so that each additive had a concentration 10 times the blending amount, and then the whole was mixed by a blender. . The extrusion conditions were a discharge rate of 20 kg / h, a screw rotation speed of 150 rpm, a vent vacuum of 3 kPa, and an extrusion temperature of 280 ° C. from the first supply port to the die part.

  After drying the obtained pellets at 120 ° C. for 5 hours in a hot air circulating dryer, using an injection molding machine, the cylinder temperature was 280 ° C., the mold temperature was 80 ° C., and the firing speed was 20 mm / sec. A smooth flat test piece having a length of 150 mm, a width of 150 mm, a thickness of 2 mm, and a surface arithmetic average roughness (Ra) of 0.03 μm was molded. As an injection molding machine, Toshiba Machine Co., Ltd. product: IS150EN-5Y was used. The evaluation results of the obtained molded plate are shown in Table 1.

In addition, the content of each component indicated by symbols in Table 1 is as follows.
(Component A)
PC: Linear aromatic polycarbonate resin powder synthesized by interfacial polycondensation method from bisphenol A, p-tert-butylphenol as a terminal terminator, and phosgene (manufactured by Teijin Chemicals Ltd .: Panlite L-1250WP (trade name)) , Viscosity average molecular weight 23,700)

(B component)
All of the following B-1 to B-3 have an average particle diameter of about 2 μm, and the particle diameter distribution is almost the same.
B-1: Polymethylsilsesquioxane particles having a 1% weight loss temperature of 481 ° C. measured by TGA measurement (manufactured by Nikko Rica Co., Ltd .: MSP-S020 (trade name), average particle size: 2.1 μm)
B-2: Polymethylsilsesquioxane particles having a 1% weight loss temperature measured by TGA of 345 ° C. (manufactured by GE Toshiba Silicones Co., Ltd .: Tospearl 120 (trade name), average particle size 1.8 μm)
B-3: Polymethylsilsesquioxane particles having a 1% weight loss temperature measured by TGA of 285 ° C. (manufactured by Shin-Etsu Chemical Co., Ltd .: KMP-590 (trade name), average particle size 2.2 μm)

(C component)
PEP: Pentaerythritol diphosphite antioxidant (Asahi Denka Kogyo Co., Ltd .: ADK STAB PEP-8 (trade name))
(D component)
IRG: Hindered phenol-based antioxidant (CIBA SPECILITY CHEMICALS: Irganox 1076 (trade name)
(E component)
PSR: Coumarin-based optical brightener (manufactured by Hakkol Chemical Co., Ltd .: Hakkor PSR-B (trade name))
(F component)
UVA: Benzotriazole ultraviolet absorber (Chemipro Kasei Co., Ltd .: Chemisorb 79 (trade name))

  As is apparent from Table 1, it can be seen that the light diffusing resin composition of the present invention has an excellent hue of diffused light and is excellent in luminance when incorporated in a direct type backlight. That is, it can be seen that the resin composition has characteristics suitable for various light diffusion plates and light diffusion molded products. Moreover, the tendency which exhibits favorable brightness | luminance is recognized, so that the TGA 1% weight reduction | decrease temperature of the polyorgano sesquioxane particle | grains mix | blended is high.

FIG. 1 is a schematic view showing a method for measuring the degree of dispersion in the present invention. FIG. 2 is a simplified cross-sectional view of the evaluation apparatus of the present invention. FIG. 3 is a simplified plan view of the evaluation apparatus of the present invention.

Explanation of symbols

A Test piece (flat plate)
B Light source γ Diffuse light angle 1 Test piece 2 White reflective resin plate 3 to 10 Light source (cold cathode tube)
11 to 19 measuring points

Claims (6)

  (A) 100 parts by weight of an aromatic polycarbonate resin (component A) and (B) polyorganosilsesquioxane particles having a 1% weight reduction temperature of 400 to 500 ° C. in thermogravimetry (TGA) according to JIS K7120 (B component) A light diffusing aromatic polycarbonate resin composition comprising 0.005 to 20 parts by weight.   The light-diffusing aromatic polycarbonate resin composition according to claim 1, wherein the component B is polymethylsilsesquioxane particles.   (C) phosphorus stabilizer (C component) 0.0001 to 1 part by weight and / or (D) hindered phenol compound (D component) 0 with respect to 100 parts by weight of the aromatic polycarbonate resin of component A The light-diffusing aromatic polycarbonate resin composition according to any one of claims 1 and 2, comprising 0.001 to 1 part by weight.   (E) 0.005 to 0.5 parts by weight of fluorescent brightening agent (E component) and / or (F) ultraviolet absorber (F component) with respect to 100 parts by weight of the A component aromatic polycarbonate resin. The light-diffusing aromatic polycarbonate resin composition according to any one of claims 1 to 3, comprising 001 to 2 parts by weight.   The light diffusing plate formed from the light diffusable aromatic polycarbonate resin composition of any one of the said Claims 1-4.   The light diffusing plate for direct type backlights formed from the light diffusable aromatic polycarbonate resin composition of any one of the said Claims 1-4.

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