TW200921152A - Resin composition for optical diffusion plate, optical diffusion plate thereof, and process for producing the same - Google Patents

Abstract

This invention relates to a resin composition for diffusion plate, which comprises certain styrene-based resins and diffusion agents, and to a diffusion plate formed by the same. Specifically, the styrene-based resins are made by copolymerizing the styrene-based monomers with multi-branch macromonomer having a plural of multi-branches, wherein the multi-branch macromonomer has plural polymeric double bonds on the tip. Thus a diffusion plate having well diffusion property, low hygroscopic activity, and low uneven penetration is available. In addition, an ejection forming method is used with styrene-based resins to form a diffusion plate and to process its surface.

Description

[Technical Field] The present invention relates to a resin composition for a light-diffusing sheet, and a light-diffusing sheet obtained by molding the resin composition, and a method for producing the same, wherein the light-diffusing sheet is used The resin composition contains a styrene resin having a branched structure and a light diffusing agent, and has excellent processability, and the obtained light diffusing plate is excellent in light diffusibility, low water absorbability, and unevenness in transmittance. [Prior Art] In recent years, high brightness, thinning, and high brightness uniformity in the field of transmissive displays have been sought. Some people have proposed a direct type backlight, which is a combination of a plurality of light sources and a reflective plate on the back side. Become a diffuser plate for the light-emitting surface. This device is characterized in that the light beam utilization efficiency is high and the luminance is high. On the other hand, since the luminance is high above the light source, there is a problem that the luminance of the light-emitting surface is deteriorated. In particular, this problem becomes more remarkable when the distance between the diffusing plate and the light source becomes closer as the backlight device is thinned. Conventionally, a method of obtaining a light diffusing plate used in the above backlight device having both transparency and diffusibility has been studied for a transparent substrate of methacrylic resin, styrene styrene resin, styrene resin or the like. A method of blending a resin having a refractive index different from that of the resin as a light diffusing agent (for example, refer to Patent Documents 1 to 3). In the case of a large-sized liquid crystal display, the under-type backlight method has become the mainstream, and since the bending of the light-diffusing sheet will become large due to the use environment, uneven brightness will appear, and lower moisture absorption is sought for the use of the substrate. . In addition, for uneven brightness, since the unevenness of the diffusion rate of the diffusing plate is greatly affected, the unevenness of the thickness or the unevenness of the light diffusing agent is eliminated, and the processability or dispersion uniformity of the substrate having superiority of 200921152 will also be changed. It is important. In this manner, in the light diffusing plate, in addition to the requirement of light diffusibility, the resin composition used is required to have superior processability, low transmittance unevenness, and low hygroscopicity, and it has not been obtained at the same time. characteristic. [Patent Document 1] Japanese Laid-Open Patent Publication No. Hei No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. No. Hei. In view of the above circumstances, the technical problem to be solved by the present invention is to provide a resin composition for a light-diffusing sheet, and a light-diffusing sheet obtained by molding the resin composition and a method for producing the same. In order to solve the above-mentioned problems, the inventors of the present invention have found the following facts in order to solve the above-mentioned technical problems: the light diffusing agent is blended into a specific styrene resin having a branched structure. The resin composition or the light diffusing plate processed by the resin composition has superior light diffusibility, low water absorption, workability, and low transmittance unevenness. In other words, the present invention provides a resin composition for a light-diffusing sheet, a light-diffusing sheet obtained by using the resin composition, and a method for producing the same, the resin composition for a light-diffusing sheet containing a styrene resin (A) and light diffusion The agent (B) is characterized in that the styrene resin (A) contains a multi-branched macromonomer (al) having a plurality of branches and having a plurality of polymerizable double bonds at its tip end, and styrene A resin obtained by copolymerizing a monomer (a2). [Effects of the Invention] 200921152 The resin composition for a light-diffusing sheet of the present invention has excellent processability, and the obtained light-diffusing sheet has uneven light diffusibility, low water absorbability, and low transmittance, and is particularly used for increasing the size. A light diffusing plate of a liquid crystal display directly under the backlight type is useful. In addition, the high workability of the resin composition for a light-diffusing sheet of the present invention and the homogeneity of the composition are, for example, a micro-fabrication on the surface to improve the light-diffusing effect, and the like, and the diffusion plate can be simultaneously used. From the viewpoint of the injection molding method for forming and surface processing, it is also energy-saving and productivity, which is a highly useful material. [Embodiment] [Embodiment of the Invention] Hereinafter, the present invention will be described in detail. [Styrene-based resin (A)] The styrene-based resin (A) used in the present invention must contain a multi-branched macromonomer having a plurality of branches ' and having a plurality of polymerizable double bonds at its tip end portion ( Al) A multi-branched resin obtained by copolymerizing a styrene monomer (a2). Further, the styrene-based resin (A) used in the present invention is a resin having a multi-branched structure obtained by copolymerizing a multi-branched macromonomer (al) and a styrene-based monomer (a2), and is copolymerized. In the meantime, a homopolymer (linear resin) of the styrene monomer which is simultaneously formed may be contained. Further, a linear resin prepared in advance may be used by mixing a resin obtained by copolymerizing a multi-branched macromonomer (al) with a styrene monomer (a2). The fluidity of the styrene-based resin (A) is preferably 2.0 or more in terms of mold reproducibility, shortening of the molding cycle, and superior balance with the appearance and strength of the obtained light-diffusing sheet. The following resins. 200921152 [GPC-MALS] When the molecular weight of the styrene-based resin (A) used in the present invention is measured by GPC-MALS (MALS: Multi-Angle Light Scattering Detector), for example, the layer shown in FIG. 2 can be obtained. Analysis of the map. In Fig. 2, the peak on the low molecular weight side is P 1, and the peak on the high molecular weight side is P 2 . It is presumed that the peak of P 1 contains a linear resin and a low-branched resin. Further, it is presumed that the peak P2 mainly contains a multi-branched high-branched resin. Also, the region of the peak P2 is perpendicular to the baseline (in the second graph, the dotted line drawn almost parallel to the volume axis) from the highest point of the peak P2, and from the highest point a region surrounded by the molecular weight curve on the left side (1); a molecular weight curve formed by folding to the right side with the perpendicular axis as the axis of symmetry (in Fig. 2, the hypothetical molecular weight shown by the dotted line on the right side of the vertical line Curve), the area formed by the vertical line and the area enclosed by the baseline (2). Further, the region of the peak P 1 is a portion of the region of the peak P 1 obtained by subtracting the region (1) from the region (2) from the region surrounded by the molecular weight curve and the baseline. [Molecular weight of styrene-based resin (A)] The styrene-based resin (A) used in the present invention is a weight average molecular weight determined by GPC-MALS, preferably 150,000 in terms of strength and workability. 550,000, more preferably 250,000 to 500,000. When the weight average molecular weight is 15,000 or less, there is a tendency that the strength is lowered; and the case of 550,000 or more has a tendency to lower the workability. [Slope of the two-log graph of the styrene-based resin (A)] The styrene-based resin (A) is obtained from GPC-MALS based on the viewpoint of superior balance strength and moldability. The molecular weight of the resin is the horizontal axis, the two axes of the vertical axis are the vertical axis, and the molecular weight is 250,000 to 1 in the graph. The slope on the 10,000-degree region is preferably 0.35 to 0.45. If the slope is larger than 0.45, it becomes closer to the physical properties of the linear resin; on the contrary, if it is smaller than 0 · 35, the molecular weight accompanying the increase in branching degree will increase, and the fluidity will decrease, and the forming process will be performed. Sex has an impact. [Mixed ratio of resin in peak P1 region to resin in peak P2 region] Resin and peak P2 in peak P1 region of styrene resin (A) from the viewpoint of superior strength and formability The mass ratio of the resin in the region: (resin in the peak P2 region of the resin / peak P 1 region) is preferably from 3 0/70 to 70/30, more preferably from 40/60 to 60/40. This ratio can be easily controlled based on the adjustment of the ratio of the use of the multi-branched macromonomer (al) to the styrene monomer (a2), the type of the chain transfer agent, and the amount thereof. [Multi-branched macromonomer (al)] Based on the viewpoint that the styrene-based resin (A) having various characteristics as described above can be easily obtained, in particular, the weight average molecular weight of the multi-branched resin is controlled to 1, 〇〇〇 In view of the following, a plurality of branches having the plurality of branches used in the present invention and having a plurality of polymerizable double bonds at the tip end thereof have a plurality of branches and are at the tip end portion thereof. The weight average molecular weight (Mw) having a plurality of polymerizable double bonds is preferably from 1,000 to 15,000, still more preferably from 3,000 to 8,000. The branching structure is not particularly limited, and it is preferred that the electron attracting group is bonded to the carbon atom of the carbon atom at all three bonding ends except for the bonding end bonded to the electron attracting group. Branched matter, and a branched structure formed according to a repeating structural unit having an ether bond, an ester bond or a guanamine bond. The multi-branched resin is in the form of a branched structure 200921152 according to the above-mentioned four-stage carbon, and the content of the electron-attracting group per lg of the branched resin is preferably 2.5\10 - 4111111 〇 1 - 5.0 < 10_11 The range of ^111〇1 is further preferably in the range of 5.0 x lO - 4 mmol to 5.0 x l 〇 - 2 mmol. The tip end portion of the multi-branched macromonomer (al) must have two or more polymerizable double bonds per molecule, and particularly preferably a double bond directly bonded to the aromatic ring. The content of the polymerizable double bond per lg of the macromonomer is preferably from 0.1 to 5.5 mmol, more preferably from 5 to 3.5 mmol. In the case where O.lmmol is small, a high molecular weight multi-branched resin will become difficult to obtain; f) in the case of more than 5.5 m m ο 1, the molecular weight of the multi-branched resin tends to increase excessively. [Multi-branched macromonomer (al-i)] The branched structure of the multi-branched resin used in the present invention is derived from the branched structure contained in the multi-branched macromonomer (al) used, multi-branched One of the preferred macromonomers (al) is exemplified by a multi-branched macromonomer (al-i) which is an electron-attracting group in one molecule and bonded to the bonding end of the electron-attracting group. The three bonding ends are all bonded to carbon atoms (the branching structure of the 4th carbon atom, and the double bond directly bonded to the aromatic ring. This multi-branched macromonomer (al-i) A high-branched macromonomer derived from an AB2 type monomer. Such a branched structure is readily obtainable by a nucleophilic substitution reaction of an active methylene group bonded to an electron attracting group. For example, the electron attraction歹可歹1J: a CN, a NO, -CONH2, a CON (R) 2, a S02CH3, -P ( = 0) (OR) 2, etc. Bonding the methylene groups of these electron attracting groups has been In the case of direct bonding to an aromatic ring or a carbonyl group, the activity of the methylene group will become higher. -10- 200921152 For example, the multi-branched macromonomer (a 1 - i It is preferably a substance having a repeating unit represented by the following formula (1): (1) -^Z-Y2-C^· [wherein, Υι is a CN, an N〇2, a CONH2 , a CON(R) 2, —S02CH3 or a P(=0)(0R)2 (wherein R is an alkyl group or an aryl group), Y2 is an extended aryl group, and Z is —(CH2) n〇 —, —(CH2CH2〇) η—or one (CH2CH2CH2O) η — > Υ2 is a 〇—CO—or an NH—CO—in the case where Z is a (CH2)n—, —(CH2)nAr — —(CH2) n0—Ar—, —(CH 2 CH 20 ) n — Ar — or —(CH 2 CH 2 CH 2 0 ) n —Ar — (wherein Ar is an extended aryl group). In addition, n is 1 to 12 Y2 in the formula (1) is suitably an aryl group shown below. In the structural unit represented by the formula (1), γ 1 is preferably a CN, and Y 2 is preferably a stretch. Phenyl. Υ 2 is a case where a phenyl group is stretched, and the bonding position of ruthenium may be any of ortho, meta or para is not particularly limited, and preferably is para. In addition, based on styrene alone The solubility of the body is good, and η in the formula is preferably 2 to 1 Å.

The multi-branched macromonomer (al -i ) having the branched structure can be obtained by the reaction of the following (1) and (2) in the presence of the test -11 - 200921152 compound: 1) nucleophilic substitution reaction of an AB 2 type monomer having a leaving group in a nucleophilic substitution reaction of an active methylene group with an active methylene group in one molecule to obtain a multi-branched self-condensing polycondensate ( Obtaining a reaction of the precursor); and (2) reacting the unreacted active methylene or methylene group remaining in the polycondensate with a double bond and active methylene group directly bonded to the aromatic ring in one molecule The compound of the leaving group in the nucleophilic substitution reaction of the group is subjected to a nucleophilic substitution reaction. Here, the cleavage group in the nucleophilic substitution reaction of the active methylene group means a halogen bonded to any one of saturated carbon atoms, - 〇S(=0) 2R (R represents an alkyl group or an aryl group), and the like. Specific examples thereof include bromine, chlorine, methylsulfonyloxy, and toluenesulfonyloxy. The basic compound may, for example, be a strong base such as sodium hydroxide or potassium hydroxide, and may be used as a water solution during the reaction. An AB2 type monomer having a leaving group in a nucleophilic substitution reaction of an active methylene group and an active methylene group in one molecule, for example, bromoethoxy-phenylacetonitrile, chloromethylbenzyloxy-benzene Halogenated alkoxy-phenylacetonitriles such as acetonitrile; tosyloxy-(ethoxy)-phenylacetonitrile, toluenesulfonyloxy-bis(ethoxy)-phenylacetonitrile, etc. Phenyloxyl phenylacetonitriles. Representative examples of the cleavage group in the nucleophilic substitution reaction in which a double bond directly bonded to an aromatic ring is bonded to an active methylene group in one molecule include, for example, chloromethylstyrene, bromomethylstyrene, and the like. . -12- 200921152 The above (1) is a reaction for synthesizing a polycondensate as a precursor, and (2) is a reaction in which a double bond directly bonded to an aromatic ring is introduced into a precursor. (1) and (2) can carry out the respective reactions one by one, and can also be carried out simultaneously in the same reaction system. The molecular weight of the multi-branched macromonomer (al-i) can be controlled by changing the blend ratio of the AB2 type monomer to the basic compound used as a raw material. [Multi-branched macromonomer (al-ii)] In the present invention, a multi-branched macromonomer (a 1 ) which can be used can be listed (': by repeating having an ester bond, an ether bond or a guanamine The branching structure formed by the structural unit of the bond and the multi-branched macromonomer (al-ii) having two or more polymerizable double bonds in one molecule at the end of the branch. The structural unit having the ester bond is repeated to form a branch A branched macromonomer (a 1 - ii -1 ) having a branched structure, preferably a preferred embodiment, wherein a polymerizable double bond such as a vinyl group or an isopropenyl group is introduced into a carbon adjacent to an ester bond carbonyl group forming a molecular chain. A multi-branched polyester polyol having an atom of a 4-stage carbon atom. The introduction of a polymerizable double bond into a multi-branched polyester polyol can be carried out by an esterification reaction or a addition reaction. The dendritic polyester polyol is commercially available as "Boltorn H20, H30, H40" manufactured by Perstorp Co., Ltd. The multi-branched polyester polyol can be introduced into a part of its hydroxyl group in the substituent by an ether bond or other bonding in advance. In addition, one part of its hydroxyl group can also be obtained by oxidation reaction or other reaction. In addition, a multi-branched polyester polyol may also be esterified in one part of the hydroxyl group. The multi-branched macromonomer (al-ii-Ι), for example, may be a carbon adjacent to a carboxyl group. a monocarboxylic acid having four or more carbon atoms and having two or more hydroxyl groups, and reacting with a compound having one or more hydroxyl groups to form a multi--13-200921152 branched polymer, followed by acrylic acid or methacrylic acid An unsaturated acid, an isocyanate group-containing acrylic compound, or the like, which is obtained by reacting a hydroxyl group of the terminal group of the polymer, and a multi-branched polymerization which forms a branched structure by repeating a structural unit having an ester bond. "A' has been disclosed in "Angew. Chem. Int. Ed, Engl. 1, 29" by Tamalia et al. p. 138~177 (1990) ° The compound having more than one hydroxyl group by a) aliphatic Alcohol, alicyclic diol or aromatic diol, b) triol, c) tetraol, d) sugar alcohol such as sorbitol and mannitol, e) dehydrated hexaheptitol or dipentaerythritol, f) Α-alkyl glucoside such as α-methyl glucoside, g) ethanol, hexanol, etc. a hydroxyl group formed by reacting a functional alcohol, h) an alkoxide having a weight average molecular weight of at most 8,000 or a derivative thereof, with a hydroxyl group of one or more compounds selected from any one of the above a) to g) Polymers, etc. The a) aliphatic diol, alicyclic diol or aromatic diol, for example, 1,2-ethanediol, 1,3-propanediol, 1,4-butanediol, 1,5- Pentandiol, 1,6-hexanediol, polytetrahydrofuran, dimethylolpropane, neopentylpropane, 2-propyl-2-ethyl-1,3-propanediol, 1,2-propanediol, 1, 3-butanediol, diethylene glycol, triethylene glycol, polyethylene glycol, dipropylene glycol, tripropylene glycol, polypropylene glycol: cyclohexanedimethanol, 1,3-dibenz-5,5-dimethanol ; 1,4-dimethylbenzene dimethanol, 1-phenyl-I, 2-ethane glycol, and the like. The b) triol, for example, may be exemplified by trimethylolpropane, trimethylolethane, trimethylolbutane, glycerol, I,2,5-hexanetriol, I, 3, 5 · Tribasic benzene and the like. The C) tetraol may, for example, be pentaerythritol, bis(trimethylol)propane, diglycerin or bis(trimethylol)ethane. The carbon atom adjacent to the carboxyl group is a 4-stage carbon atom, and has 2 single-residual acids having a radical of -14 to 200921152. For example, dimethicone, α, α-di (hydroxyl) may be mentioned. Butyl acid, α,α,α-tris(hydroxymethyl)acetic acid, α,α-bis(hydroxymethyl)pentanoic acid, α,α-bis(hydroxymethyl)propionic acid, and the like. By using the monocarboxylic acid 'ester decomposition reaction, it is suppressed, and a multi-branched polyester polyol can be formed. Further, in the production of the multi-branched polyester polyol, a catalyst is preferably used. For example, the catalyst may be exemplified by dialkyltin oxide, dialkyltin halide, dialkyltin dicarboxylate, or oxidized. An organotin compound such as phenbutyltin; a titanate such as tetrabutyl titanate; an organic sulfonic acid such as Lewis acid or p-toluenesulfonic acid. A multi-branched macromonomer (al-ii-2) having a branching structure having an ether bond structure and having a branched structure, for example, a cyclic ether compound having one or more hydroxyl groups and having one or more The hydroxy compound is reacted to form a multi-branched polymer, and then an unsaturated acid such as acrylic acid or methacrylic acid, an acrylic compound containing an isocyanate group, or a halogenated methyl styrene such as 4-chloromethylstyrene is used. The hydroxyl group of the terminal group of the polymer is reacted. In addition, the method for producing the multi-branched polymer is based on the ether synthesis method of Williamson, and a method of reacting a compound having one or more hydroxyl groups with a compound containing two or more hydroxyl groups and a halogen atom, an OS〇2〇CH3 or a 0S02CH3. Also useful. A compound having one or more hydroxyl groups can be used, and a cyclic ether compound having one or more hydroxyl groups can be used, and examples thereof include 3-ethyl-3-(hydroxymethyl)butylene oxide and 2 , 3-epoxy-1-propanol, 2,3-epoxy-butanol, 3,4-epoxy-1-butanol, and the like. The compound having one or more hydroxyl groups used in the Williamson ether synthesis method may be the above compound, and is preferably a compound having two or more hydroxyl groups bonded to the aromatic ring. -15- 200921152 The compound may, for example, be 1,3,5-trihydroxybenzene, 1,4-dimethylbenzene dimethanol or 1-phenyl-1,2-ethanediol. Further, a compound containing two or more hydroxyl groups and a halogen atom, an OSO2OCH3 or an OSO2CH3, for example, 5-(bromomethyl)-1,3-dihydroxybenzene, 2-ethyl-2-(bromo-methyl) -1,3-propanediol, 2-methyl-2-(bromomethyl)-1,3-propanediol, 2-(bromomethyl)-2-(hydroxymethyl)-1,3-propanediol . Further, in the production of the above-mentioned multi-branched polymer, a general catalyst is preferably used, and examples of the catalyst include BF3 diethyl ether, FS03H, C1S03H, HC104 and the like. Further, a multi-branched macromonomer (al-ii-3) having a branched structure of a guanamine bond to form a branched structure is repeated, and for example, a molecule having a nitrogen atom and having a guanamine bond in a repeating structure may be mentioned. The Generation 2.0 (PAMAM dendrimer) manufactured by Dentoritech Corporation is representative. [Polymerization method of multi-branched macromonomer (al) and styrene monomer (a2)] By copolymerizing the multi-branched macromonomer (al) and the styrene monomer (a2), A resin mixture of a multi-branched resin and a mixture of a linear resin and a low-branched resin which are simultaneously produced according to polymerization conditions is obtained. In this case, it is preferred to use the above-mentioned multi-branched macromonomer (al) in a ratio of 50 ppm to 1%, more preferably in a ratio of from 100 ppm to 3,000 ppm, more than the styrene monomer (a2). The formation of the dendritic resin is easy, and the suppression of gelation is simple, and the styrene resin (A) used in the present invention can also be obtained efficiently. Various polymerization methods can be applied in the polymerization reaction. The polymerization mode is not particularly limited, and is preferably a bulk polymerization, a suspension polymerization or a solution polymerization. Among them, from the viewpoint of production efficiency, particularly continuous block polymerization is particularly desirable, for example, -16 - 200921152 by assembling a tubular reactor having a plurality of mixing elements in which one or more stirred reactors and a non-movable portion are fixed inside. Continuous block polymerization 'can be obtained with superior resin. Although it can be thermally polymerized without using a polymerization initiator, it is preferred to use various radical polymerization initiators. In order to reduce the viscosity of the reactant in the polymerization reaction, an organic solvent may be added to the reaction system. The organic solvent may, for example, be toluene, ethylbenzene, xylene, acetonitrile, benzene, chlorobenzene or the like. Chlorobenzene, anisole, cyanobenzene, dimethylformamide, N,N-dimethylacetamide, methyl ethyl ketone, and the like. In particular, in the case where the addition amount of the multi-branched macromonomer (a 1 ) is to be increased, it is preferred to use an organic solvent from the viewpoint of suppressing gelation. Thereby, the amount of addition of the multi-branched macromonomer (al) previously shown can be greatly increased, and gelation becomes difficult to occur. The radical polymerization initiator is not particularly limited, and, for example, 1,1-bis(t-butylperoxy)cyclohexyl, 2,2·bis(t-butylperoxy)butane Peroxy ketals such as alkane, 2,2-bis(4,4-diperoxy-tert-butylcyclohexyl)propane; hydroperoxide of cumene hydroperoxide, tert-butyl hydroperoxide, etc. a dialkyl peroxide such as a third butyl peroxide, a dicumyl peroxide, or a second hexyl peroxide; a peroxidation of benzammonium peroxide, bismuth peroxide, etc. Dioxins; peroxy esters of perbutyltributyl peroxybenzoate, dibutylbutyl isophthalate peroxide, tributyl isopropyl monocarbonate; n, N'-azobisisobutyronitrile, N,N'-azobis(cycloheximide-1-carbonitrile), N,N'-azobis(2-methylbutyronitrile), hydrazine, Ν'- An azo (2,4-dimethylvaleronitrile), an anthracene, an anthracene, an azo-[2-(hydroxymethyl)propanenitrile], or the like may be used in combination of one or more of them. -17- 200921152 Further, in order not to increase the molecular weight of the obtained resin mixture too much, a chain transfer agent may be added. As the chain transfer agent, a monofunctional chain transfer agent having a chain transfer group can be used, and a polyfunctional chain transfer agent having a plurality of chain transfer groups can also be used. The monofunctional chain transfer agent may, for example, be an alkyl mercaptan or a mercaptoacetate. The polyfunctional chain transfer agent may be exemplified by esterification of ethylene glycol, neopentyl glycol, trimethylolpropane, pentaerythritol, dipentaerythritol, tripentaerythritol, sorbitol, etc. by using thioglycolic acid or 3-mercaptopropionic acid. a hydroxyl group in an alcohol or the like. V: The styrene monomer (a2) which can be used in the present invention is styrene and a derivative thereof, and examples thereof include styrene, methyl styrene, dimethyl phenyl benzene, and dimethyl benzene. , phenyl benzene, diethyl benzene, triethyl styrene, propyl styrene, butyl styrene, hexyl styrene, heptyl benzene, suspected, phenyl benzene, etc. Ethylene; fluorostyrene, chlorostyrene, bromostyrene, dibromostyrene, iodine styrene and the like halogenated styrene, further examples of: nitrostyrene, ethyl styrene styrene, methoxy styrene, etc. It can be used alone or in combination of two or more. It is preferable to use styrene among these monomers based on the viewpoint that it is more excellent (and: the more general use is used. In addition, it can be used together with the styrene monomer (a2) without damaging the application of the present invention. In the range of the effect of the case, it may be used together with another polymerizable monomer such as an acrylic monomer or a vinyl monomer, and it is preferred to use the styrene monomer (a2) in an amount of 90% by mass or more of all the monomers. More preferably, the styrene monomer (a2) is used in an amount of 95% by mass or more. [Light diffusing agent (B)] The light diffusing agent (B) used in the present invention is not particularly limited as long as it is generally used. The styrene resin (A) -18-200921152 can be used as the inorganic or organic transparent fine particles having a different refractive index. The inorganic diffusing agent 'for example' can be exemplified by calcium carbonate, barium sulfate, and oxidation. Titanium, aluminum hydride, cerium oxide, glass, mica, zinc oxide, etc., such light diffusion may be a surface treatment of a fatty acid or a ruthenium oxy-coupling agent, or an 'organic light diffusing agent, for example, : styrene-propylene particles In the case of the acrylic fine particles, the acrylonitrile fine particles, etc., the acrylic fine particles are those which are composed of 50% by mass or more of a propionic acid monomer such as methyl methacrylate or butyl methacrylate. It is generally called a decyl alkane resin, a decane rubber, etc., and can be suitably used for a body shape at normal temperature. Moreover, when necessary, the light-diffusion agent (B) can also be used after mixing two or more. The diffusing agent (B) is further suitable for use in cerium oxide-based fine particles and acrylic fine particles having excellent light resistance, and particularly suitable for use in light-diffusing agents (B) and styrene. The refractive index g of the resin (a) is based on the viewpoints of light diffusibility, penetrability, and brightness balance, and the absolute enthalpy is 〇5 or more and 0 _ 2 0 or less. In addition, the shape of the light diffusing agent (b) is good. From the viewpoint of light diffusibility or color tone, the average particle diameter is in the range of 1 to 10 μηη. The average particle diameter is less than 1 μηη, which has the possibility of recessive deficiency or discoloration and a slight yellow color. Another aspect, if In the case of 10 μm, there is a case where the light diffusibility is insufficient. The amount of the light diffusing agent (Β) is adjusted according to the type, particle diameter, and refractive index of the light diffusion (Β) used. The amount of the collision is preferably in the range of ～1 〇 by mass, based on the viewpoint of easy light extraction and the balance of the enthalpy. More preferably, it is 0.3 to 5 Å. The photo-oxidizing agent decanoic olefin is also solid-fixed, preferably better, and the above-mentioned resin is contained in the resin composition of the light-diffusing sheet of the present invention. The vinyl resin (A) and the light diffusing agent (B) are not particularly limited, and various additives and the like can be used. [Ultraviolet absorber] The light diffusing plate of the present invention is easily deteriorated by the lighting of the cold cathode tube constituting the backlight, and various general ultraviolet absorbers and hindered amine light stabilizers may be added. Examples of the ultraviolet absorber include a benzotriazole type, a benzophenone type, and a malonic ester type, and may be used singly or in a plurality of types. The total amount of the ultraviolet absorber and the hindered amine light stabilizer is usually 〇. 质量 1 part by mass or more and 1 part by mass or less, preferably 0.05 part by mass or more and 0.6 part by mass or less. [Antioxidant] The light diffusing plate of the present invention may contain various antioxidants in order to prevent coloration. The antioxidant may be any of a phenol type, a phosphorus type, a sulfur type, and the like, and is preferably a phosphorus-based or phosphorus-based or phenol-based one based on the viewpoint that the coloring prevention effect is high. f [Antistatic agent] V. When the light diffusing plate of the present invention is used for a long period of time, it is possible to impart an antistatic agent because of the adhesion of dust. As the antistatic agent for imparting antistatic ability, a nonionic system such as a glycerin fatty acid ester or an alkyldiethanolamine; an anionic system such as an alkylsulfonate or an alkylbenzenesulfonate; or a tetraalkyl group; A cationic type such as an ammonium salt; a low molecular weight type antistatic agent such as an amphoteric ion such as an imidazoline. Further, the addition method is not particularly limited. It may be melt-mixed in the resin composition, or may be applied to the surface of the sheet as an aqueous solution or the like. -20- 200921152 [Other Additives] In the range which does not impair the effects of the present invention, it is not particularly limited to appropriately blend other additives in the light diffusion type of the present invention, for example, an ethyl bis-slip agent and a sulphur fatty acid are exemplified. The various additives in the olefin-based resin such as a high-grade release agent, a liquid paraffin or a polyester-based plasticizer, which can be used in two or more types, can be used. In addition, for the purpose of adjusting the back color, it is also possible to add a pigment or dye (manufacture method of the light diffusing plate), and to disperse other additives such as a styrene resin (A), a light-diffusion absorber, and an antioxidant. From the viewpoint, before the processing on the board, for example, a composite is prepared by melt-mixing in advance. At this time, before the input to the twin-shaft extruder hopper, it is pre-mixed by a drum or the like and poured into the extruder. Alternatively, ϋ is added from the middle of the cylinder. Further, it is also possible to process a masterbatch having a high degree of pre-formation by using a styrene-based resin to form an arbitrary concentration of a light diffusing agent. The light-diffusing sheet of the present invention can be produced by performing two-time processing of light diffusion obtained by casting casting or the like in such a manner, and for the processing method, surface fine processing is easy, rib or hook energy From the viewpoint of good yield, it is preferable to use it in an "injection molding method". A kind of additive, such as a stearyl epoxide or the like, a fatty acid metal salt or the like, which can be added to a conventional styrene benzene, a brightness enhancement when used alone or in combination with light, or a fluorescent whitening agent. (Β), even blended with violet, based on uniform splitting using a twin-screw extruder, etc., the mixing raw material is applied to the Henschel mixer L, the feeder can be used, and the light diffusing agent concentrate (A) is first prepared and diluted. The resin composition for the transfer molding, the extrusion molding, and the resin composition for the shot plate are formed into an unnecessary form and formed into an injection mold. -21 - 200921152 The injection molding method is not limited, and the molten resin composition is uniformly flowed, and it is preferable to use a pinhole type gate having a multi-point. , molds such as side gates. Further, in order to obtain a molded article which is excellent in dimensional accuracy and which is not caused by gas, it is preferable to provide a mold for evacuating the cavity when the molten resin composition is ejected. . Further, since the end material does not occur, the loss during production is small, and it is preferably a mold having a heat lining. In the case of using a heat lining, the gate trace which is a cause of uneven brightness is not generated, and after the cavity of the molten resin composition is completed, it is also suitable to use a needle valve for blocking the gate. [Optical pattern forming method] In the light-diffusing sheet obtained by the present invention, in order to improve optical characteristics such as light diffusibility and brightness, if necessary, at least one surface of the light-diffusing sheet can be provided with a concave-convex shape, that is, Optical pattern. The method of pattern formation is not particularly limited. For example, it can be formed simultaneously with the formation of the light diffusing plate in addition to the formation of the light diffusing plate after the formation of the light diffusing plate. For example, the formation method may be a method of pattern transfer by cutting or compression of a formed light diffusion plate, and hardening in a state where the applied photo-curable resin pattern is transferred onto a light diffusion plate; The die of the different shapes of the upper pattern or the roll is formed at the same time, and the stamper engraved with the enamel pattern is further assembled into the mold, and simultaneously formed at the time of injection molding, etc., because of superior mold life. Or yield, transferability, preferably by injection molding by injection molding. [Optical Pattern Shape] The shape of the optical pattern is not limited, for example, a wrinkle-22-200921152 shape; a plurality of cross-sectional polygonal shapes are arranged in a substantially parallel shape (saw-toothed shape): plural The linear shapes of a circle or an ellipse are arranged in an approximately parallel shape (a semi-conical shape or a lentil lens); with respect to the crucible, a shape such as a V-shaped notch is engraved in a manner intersecting the prism ( For example, a pyramidal protrusion such as a quadrangular pyramid or the like). In addition, it is also possible to combine two or more designs having different shapes, angles, and pitches. [Thickness of Light-Diffusing Plate] f The thickness of the light-diffusing sheet is not particularly limited, and is preferably 0.5 mm or more and 4.0 mm or less. When the thickness is less than 0.5 mm, it is necessary to suppress the wrinkles caused by the weight of a plurality of pillars or the like. Further, when the thickness exceeds 4.0 mm, it is difficult to form and the weight of the backlight is increased. The impact. [Examples] Hereinafter, the present invention will be described more specifically by way of examples. Basically, the invention should not be limited by the scope of the embodiments. In the following, "Parts" and "%" are quality standards as long as there is no special statement. The measurement method used will be described. [GPC measurement conditions of multi-branched macromonomers] Using a rapid liquid chromatograph (HLC-8220GPC manufactured by 〇 〇 〇h Co., Ltd.), RI detector, TSK gel G 6 0 〇〇H x ; G 5 〇〇〇HX 1+G400 0H X 1+G3 00 0H X 1+TSK guard Column Hxl, solvent THF, flow rate 1.0ml/min, temperature 40 °C for multi-branched macromonomers GPC measurement. [Measurement of GPC-MALS] -23- 200921152 Using a Shodex HPLC, detector Wyatt Technology DAWN EOS, Shodex RI-101, column Shodex KF-8〇6Lx2, solvent THF, flow rate 1.0 ml / min, benzene and benzene resin GPC-MALS determination. In addition, the analysis of the GPC-MALS measurement was carried out in accordance with the analytical software AST RA of Wyatt Co., Ltd., and the weight average molecular weight was determined for the styrene resin (A), and the resin mixture obtained from GPC-MALS was obtained. The slope in the region of the molecular weight of 250,000 to 10 million in the two logarithmic graphs with the molecular weight as the horizontal axis and the radius of inertia as the vertical axis (based only on the measurement of the linear portion obtained in the molecular weight range, and is automatically calculated by the software) The slope of the approximate line). [NMR measurement method] The amount of the polymerizable double bond of the multi-branched macromonomer was determined by nuclear magnetic resonance spectroscopy (W-NMR, JNM-LA300 model manufactured by JEOL), and the number of moles per unit mass of the sample was expressed. [Melt flow rate measurement method] Measurement was carried out in accordance with JIS K7210. Further, the measurement conditions were a temperature of 200 ° C and a load of 4 9 N. [Pattern Transferability] A V-shaped prism having a pitch of 90° and a pitch of 5 μm was processed into a stamper. The stamper was assembled into a mold, injection molded, and the enamel pattern was transferred to the surface of the molded article. In this case, "the height of the molded product and the height of the stamper" are set as the pattern transfer rate, and less than 60% is set to X; 60% or more and less than 80% are set to Δ, and 80 is set. % is set to 〇 above. [Appearance and workability] When a 32-inch light-diffusing sheet having a thickness of 2 mm is formed, there is no case where the gate mark, the hair, and the residual stress are bent after forming the condition -24-200921152. The situation that occurs is set to X. [Insularity of Transmittance] In the 32-inch light diffusing plate, draw three lines parallel to the long side (the distance from the two long sides is 10 cm and the total of the central part is three), parallel to the short side. 5 lines (the distance between the two short sides is 5cm, the position of 20cm and the central part are 5). The intersection of these five points is the turbidity meter ND Η 2000 made by Nippon Denshoku Industries Co., Ltd. Determine the total light transmittance, from its maximum 値, minimum 値, average 値, according to the following formula to calculate the unevenness of the penetration rate: uneven penetration rate (%) = [(maximum 値 - minimum 値) / average 値] Χ100 [Water absorption rate] Measured in accordance with JI s Κ 7 2 0 9 . The light diffusing plate was cut into 50×50 mm, dried at 50° C., and immersed in distilled water for 24 hours, and the weight was increased from before and after the immersion, and the water absorption rate was calculated according to the following formula: Water absorption rate (%)=[(water absorption) Weight after drying - weight after drying) / weight after drying χ 1 〇〇 (Reference Example 1) Synthesis of multi-branched macromonomer (Mm-ι) equipped with a stirring device, a titration funnel, a thermometer, a nitrogen introduction device, and In a 1000 ml pear-shaped flask of a gas introduction tube, 35 g of 4-bromobis(ethylene oxide) phenylacetonitrile was dissolved in 800 ml of dimethyl hydrazine (DMSO) under a nitrogen atmosphere. The internal temperature was set to 30 t using a water bath: Thereafter, a 40 m% aqueous sodium hydroxide solution of 44 mI was added dropwise over 3 minutes. The mixture was stirred for 3 hours while maintaining the temperature at 30 ° C to obtain a precursor of a multi-branched macromonomer. Further, by dropwise addition of 50.0 g of 4-chloromethylstyrene to the reactant, the mixture was stirred for 2 hours to obtain a solution of a multi-branched macromonomer. -25-200921152 The resulting solution was filtered to remove the solid component, and the filtrate was poured into 5 l of methanol containing 225 ml of a 5 mol/L aqueous hydrochloric acid solution to precipitate a multi-branched macromonomer. The multi-branched macromonomer precipitated by suction filtration was repeatedly washed three times in the order of distilled water and methanol. The obtained multi-branched macromonomer was dried under reduced pressure for 24 hours to obtain 20 g of a branched macromonomer (Mm-oxime). This multi-branched macromonomer (Mm-Ι) is a highly branched macromonomer derived from the AB2 type monomer disclosed herein (al-i).

The weight average molecular weight (Mw) was 6,000 by measuring the result of the obtained multi-branched macromonomer (M m - 1 ) by G P C . Further, from the measurement results of W-NMR, it was confirmed that the amount of double bond introduced directly to the aromatic ring was 2.7 〇mmol/g 〇 (Reference Example 2) synthesis of multi-branched macromonomer (Mm_2) <multi-branched Synthesis of Polyether Polyol> In a 2 L flask equipped with a stirrer, a thermometer, a titration funnel and a condenser, 50.5 g of ethoxylated pentaerythritol (5 mol ethylene oxide addition pentaerythritol) was added at room temperature. BF3 diethyl ether solution (50%) lg, heated to 110 °C. While slowly controlling the heat dissipation caused by the reaction, slowly add 3 - ethyl-3-(hydroxymethyl) butylene oxide 4 50 g to the surface for 25 minutes. After the heat dissipation control, the reaction mixture was further stirred at 12 ° C for 3 hours, and then cooled to room temperature. The obtained multi-branched polyether polyol had a weight average molecular weight of 3,000 and a hydroxyl value of 530. <Synthesis of a multi-branched macromonomer having a methacryl fluorenyl group and an ethyl fluorenyl group> In a Dean-Stark decanting tube equipped with a stirrer, a thermometer and a condenser, and a reactor having a gas introduction tube, the above is added <Synthesis of Multi-branched Polyether Polyol> 50 g of multi-branched polyether polyol obtained, methacrylic acid -26-200921152 13.8 g, toluene 150 g, and hydroquinone. 6 g, p-toluenesulfonic acid ig At a rate of 3 ml/min, a nitrogen gas containing 7% of oxygen was injected into the mixed solution while stirring under normal pressure. The amount of heat was adjusted so that the amount of the distillate to the decanter was 30 g per hour, and the amount of dehydration was 2.9 g until the amount of dehydration was continued. After the completion of the reaction, the mixture was temporarily cooled, and 3 6 g of acetic anhydride and 5.7 g of aminosulfonic acid were added, and the mixture was stirred at 60 ° C for 10 hours. Thereafter, in order to remove residual acetic acid and hydroquinone, it was washed four times with 50 g of a 5% aqueous sodium hydroxide solution, and further washed once with a 50% aqueous solution of 1% sulfuric acid, and then washed with water of 50 g. Times. 2 g of p-methoxyphenol oxime. 加入 was added to the obtained organic layer, and while introducing 7% of oxygen under reduced pressure, the solvent was distilled off to obtain a multi-branched macromonomer having an isopropenyl group and an ethenyl group (Mm). -2) 60g. The obtained multi-branched macromonomer (Mm-2) had a weight average molecular weight of 3,900, a double bond introduction amount of 1.50 mmol/g, and an isopropenyl group and an ethenyl group introduction ratio of 30% and 62%, respectively. The multi-branched macromonomer (Mm-2) obtained here has a multi-branched macromonomer which forms a branched structure as a structural unit of the ether bond disclosed in (al-ii-2) herein. (Reference Example 3) Synthesis of multi-branched macromonomer (Mm-3) <Synthesis of multi-branched macromonomer having methacryl oxime group and acetamidine group> 10% of Boltorn H20, 1.25 g of dibutyltin oxide, 100 g of methyl methacrylate with isopropenyl group and 0.05 g of hydroquinone in a reaction vessel equipped with a tube, a thermometer, a condenser and a Dean-Stark decanter. At a rate of 3 ml/min, a nitrogen containing 7% oxygen was injected into the mixed solution while heating under stirring. The amount of the distillate to the decanter tube was adjusted to 15 to 2 〇g per hour to adjust the amount of heating, and the distillate in the decanter was taken out every hour. 'Additional equivalent to -27-200921152 This distillate The amount of methyl methacrylate was simultaneously reacted for 4 hours. After completion of the reaction, methyl methacrylate was distilled off under reduced pressure. To terminate the remaining hydroxyl group, acetic anhydride log and 2 g of aminosulfonic acid were added, and the mixture was stirred at room temperature for 10 hours. After removing the amino sulfonic acid by filtration, the acetic anhydride and acetic acid were distilled off under reduced pressure, and the residue was dissolved in 70 g of ethyl acetate. To remove hydroquinone, it was washed 4 times with 20 g of a 5% aqueous sodium hydroxide solution. Further, it was washed twice with 20 g of a 7 % sulfuric acid aqueous solution, and then washed twice with water 20 g. 45 g of p-methoxyphenol oxime. 加入 was added to the obtained organic layer, and under reduced pressure, 7 (': % oxygen was simultaneously distilled off to obtain a multi-branched giant having isopropenyl group and ethyl fluorenyl group. Monomer (Mm-3) llg. The obtained multi-branched macromonomer (Mm-3) has a weight average molecular weight of 3,000, a number average molecular weight of 2,100, a double bond introduction amount of 2.00 mmol/g, isopropenyl group and B. The sulfhydryl group introduction ratio is 55% and 36%, respectively. The multi-branched macromonomer (Mm-3) repeat obtained here has a structural unit which is an ether bond disclosed in (al-ii-Ι) herein. Multi-branched macromonomers of branched structure (Reference Example 4) Synthesis of multi-branched macromonomer (Mm-4) (,: <Multi-branched giant with methacryl fluorenyl group and acetamidine group Synthesis of the body> In a reaction vessel equipped with a nitrogen-containing nitrogen introduction tube, a thermometer, a condenser, a Dean-Stark decanter, and a stirrer, "Boltorn H30" 10 g and dibutyltin oxide 1 · 7 were added. 5 g of methyl methacrylate with isopropenyl group and 150 g of hydroquinone. 75 g, at a rate of 3 ml / min, mixed with nitrogen containing 7 % oxygen While heating the mixture, the mixture is heated under stirring. The amount of the distillate to the decanter is 15 to 20 g per hour, and the amount of heating is adjusted. The distillate in the decanter is taken out every hour, and the equivalent is added. This distillate amount of methyl methacrylate was reacted for 8 hours. -28- 200921152 After completion of the reaction, methyl methacrylate was distilled off under reduced pressure, and acetic anhydride was added to terminate the residual hydroxyl group. 3 g of aminosulfonic acid, stirred at room temperature for 10 hours. After filtration to remove the aminosulfonic acid, the acetic anhydride and acetic acid were distilled off under reduced pressure, and the residue was dissolved in ethyl acetate (1 g). In order to remove hydroquinone, it was washed four times with 20 g of a 5 % sodium hydroxide aqueous solution, further washed twice with 20 g of a 7 % sulfuric acid aqueous solution, and then washed twice with water 20 g. The p-methoxyphenol was rubbed. 7 g of ruthenium was added to the obtained organic layer, and the solvent was distilled off while introducing 7% of oxygen under reduced pressure to obtain a poly-f branching macromonomer (Mm-4) having 11 g of isopropenyl group and an acetamidine group. The multi-branched macromonomer (Mm-4) has a weight average molecular weight of 5,200 and a number average molecular weight of 3,6 00, the double bond introduction amount is 3.00 mmol/g, and the isopropenyl group and the acetamyl group introduction rate are 53% and 41%, respectively. The multi-branched macromonomer (Mm-4) obtained here is repeated as (al-ii-Ι) The structural unit of the ether bond revealed to form a branched multi-branched monomer. (Reference Example 5) Synthesis of a multi-branched macromonomer (Mm-5) < Synthesis of a multi-branched macromonomer of a propylene group and an acetamidine group> f having a nitrogen introduction tube containing 7% oxygen, a thermometer, and a condenser

\ J

Dean-Stark decant tube and reaction vessel equipped with a stirrer, 10 g of "Boltorn H40", 2_5 g of dibutyltin oxide, 200 g of methyl methacrylate with isopropenyl group and hydroquinone .ig were added at 3 ml/min. Speed, while injecting 7% oxygen nitrogen into the mixed solution, heating with stirring. The amount of the distillate to the decant tube was adjusted to 15 to 20 g per hour, and the amount of heating was adjusted. The distillate in the decanter was taken out every hour, and methacrylic acid equivalent to the amount of the distillate was added. At the same time as the ester, it was reacted for 10 hours. After completion of the reaction, methyl methacrylate was distilled off under reduced pressure, and 20 g of acetic anhydride and 4 g of aminosulfonic acid were added to terminate the hydroxyl group remaining in the residue -29 to 200921152, and the mixture was stirred at room temperature for 10 hours. After removing the aminosulfonic acid by filtration, the acetic anhydride and acetic acid were distilled off under reduced pressure, and the residue was dissolved in 70 g of ethyl acetate. To remove hydroquinone, it was washed with 20 g of a 5% aqueous sodium hydroxide solution. Then, it was further washed twice with 20 g of a 7 % sulfuric acid aqueous solution and then washed twice with water 20 g. 45 g of p-methoxyphenol oxime. 加入 was added to the obtained organic layer under reduced pressure, and while introducing 7% oxygen, the solvent was distilled off to obtain a multi-branched macromonomer having isopropenyl group and ethyl hydrazide group ( Mm-5)llg. The obtained multi-branched macromonomer (Mm-5) had a weight average molecular weight of 7,900, a number average molecular weight of 4,200, a double bond introduction amount of 2.90 mm〇l/g, and an isopropenyl group and an ethenyl group introduction rate of 49, respectively. % and 48%. The multi-branched macromonomer (Mm-5) obtained here is a multi-branched macromonomer having a twig structure as a structural unit of the ether bond disclosed herein (al-ii-Ι). Example 1 A mixed solution of 90 parts of styrene monomer, a multi-branched macromonomer (Mm-1) obtained in Reference Example 1 with respect to styrene monomer of 50 ppm, and a mixture of toluene and 1 part was prepared. To the styrene monomer, 300 ppPm of a third peroxide of peroxybutyl benzoate as an organic peroxide was added, and the continuous block polymerization was carried out according to the following conditions using the apparatus shown in Fig. 1: Mixing Supply of solution: 9 L / hr, reaction temperature of stirred reactor (2): 1 3 2 ° C, reaction temperature of cyclic polymerization line (I): 1 3 8 ° C, non-circulating polymerization line (II) Reaction temperature: 1 4 0 to 1 60 ° C, reflux ratio: R = F 1 / F 2 = 6. However, the F 1 system shows the flow rate of the mixed solution in the reflux cycle polymerization line, and -30-200921152 F2 shows the flow rate of the mixed solution flowing to the non-circulating polymerization line. The mixed solution obtained by the polymerization was heated to 22 ° C by a heat exchanger to remove volatile components under a reduced pressure of 50 mmHg, and then granulated to obtain a styrene resin (A-1). KMP-701 (Japan) manufactured by Shin-Etsu Chemical Co., Ltd., which is a siloxane-based fine particle of the light-diffusing agent (B), is added to the obtained styrene-based resin (A-1). -1 ) 'Premixed using a roller to obtain a resin composition for a light diffusing plate. Further, the mixture was mixed with a 30 m m φ twin-screw extruder to obtain a composite of nine particles. The composite obtained by drying for 3 hours at 7 ° C was formed by a 450 ton injection molding machine to carry out a 32 Å diffusion plate having a thickness of 2 mm. Example 2 The same procedure as in Example 1 was carried out except that a multi-branched macromonomer (M m - 2 ) was used in place of the multi-branched macromonomer (M m -1 ) in Example 1. Resin (A · 2 ). 0 to 7 parts of the light diffusing agent (B - 1 ) was added to 100 parts of the obtained styrene resin (A - 2 ), and a roller was used for preliminary mixing. The mixture was melt-mixed in the same manner as in Example 1 and supplied to the material for injection molding to obtain a 32-inch diffusion plate. Example 3 The same procedure as in Example 1 was carried out except that a multi-branched macromonomer (M m - 3 ) was used in place of the multi-branched macromonomer (Mm-1) in Example 1. Resin (A - 3 ). 0.7 part of the light diffusing agent (b - 1 ) was added to 100 parts of the obtained styrene resin (A - 3 ), and a roller was used for preliminary mixing. The mixture was melt-mixed in the same manner as in Example 1 and supplied to the material for injection molding to obtain a 32-inch diffusion plate. -31-200921152 A chromatogram of GPC-MALS of the obtained styrene resin (A_3) is shown in Fig. 2. The horizontal axis represents the amount of solvent (residence time) from the start of the measurement. The vertical axis represents the peak intensity, and the component peak having a smaller solvent amount has a higher molecular weight. The solid line in the figure is determined by measuring the peak. For the mass ratio of the high molecular weight fraction (P2) to the low molecular weight fraction (P1), from the highest peak of the high molecular weight fraction to the perpendicular of the horizontal axis, the area of the line symmetry and the high molecular weight fraction of the high molecular weight fraction is determined and the whole Subtract the area ratio of the remainder of these parts. The other examples and comparative examples were also found in Tables 1 and 2 by the same method to obtain the ratio (P 2 ) / (P 1 ) of (P 2 ) to (P 1 ). The two logarithmic plots of the molecular weight and the radius of inertia obtained from G P C - M A L S of the obtained styrene resin (A - 3 ) are shown in Fig. 3. Example 4 A mixed solution of 90 parts of styrene monomer, 1800 ppm of a styrene monomer, and a mixed solution of a multi-branched macromonomer (Mm-3) obtained in Reference Example 3 and 10 parts of toluene was prepared. The styrene monomer was further added with 300 00 ppm of a third butyl benzoate peroxide as an organic peroxide, and the device shown in Fig. 1 was used for continuous block polymerization according to the following conditions: supply of mixed solution Amount: 9 L/hr, reaction temperature of stirred reactor (2): 132 ° C, reaction temperature of circulating polymerization line (I): 1 3 8 ° C, reaction temperature of non-circulating polymerization line (11): 1 5 0 to 1 7 0 ° C, reflux ratio: R = F 1 / F 2 = 6. However, the F 1 system shows the flow rate of the mixed solution in the reflux cycle polymerization line, and the F 2 system shows the flow rate of the mixed solution flowing to the non-circulating polymerization line. -32-200921152 The benzene styrene resin (A-4) was obtained by heating a mixed solution obtained by polymerization to a temperature of 2200 ° C under a reduced pressure of 5 OmmHg to remove a volatile component. To the obtained styrene resin (A - 4 ) 10 parts, 7 parts of a light diffusing agent (B-1) was added and premixed using a roller. The mixture was melt-mixed in the same manner as in Example 1 and supplied to the material for injection molding to obtain a 32-inch diffusion plate. Example 5 The styrene-based resin (A-4) obtained in the same manner as in Example 4 was prepared by adding Nippon Catalyst Co., Ltd. as a light-diffusing agent. EpOsterMA1002 (B-2), use a roller to prepare for mixing. The mixture was melt-mixed in the same manner as in Example 1 and supplied to the injection-molded material to obtain a 32-inch diffusion plate. Example 6 The styrene resin (A - 4 ) obtained in the same manner as in Example 4 was subjected to 'addition of 〇·7 parts of light diffusing agent (b-1) and 0.1 part of ultraviolet light absorption. Tinuvin P manufactured by Ciba Specialty Chemicals Co., Ltd. of the agent 1 and 0.03 parts of Irg an ox 1076 manufactured by Ciba Specialty Chemicals Co., Ltd. as an antioxidant 1 and 7 parts of Irgafosl 68' manufactured by Ciba Specialty Chemicals Co., Ltd. as an antioxidant 2 Prepare for mixing. In the same manner as in the example, the mixture was supplied by melt-mixing the mixture to the material for injection molding to obtain a 32-inch diffusion plate. Example 7 In 100 parts of the styrene resin (A-4) obtained in the same manner as in Example 4, 0.45 parts of the light diffusing agent (H) and 〇^-33-200921152 parts of ultraviolet light were added. Agent 1, 0 · 0 3 parts of antioxidant 1, ο. 0 7 parts as antioxidant 2, using a roller to prepare for mixing. A 32-inch prism diffusion plate having a thickness of 2 mm was obtained by performing melt-mixing of the mixture in the same manner as in Example 1 using a mold for assembling a stamper (V-shaped, 90, 5 μm pitch). Example 8 In a 100 parts of the styrene resin (A - 4 ) obtained in the same manner as in Example 4, 2 parts of a light diffusing agent (B - 1 ) and 〇·1 part of Γ were added. Ultraviolet absorber 1, 〇. 〇 3 parts of antioxidant 1, 0.07 parts of the antioxidant 2, using a roller to prepare for mixing. This mixture was melt-mixed in the same manner as in Example 1 and injection-molded using a mold for assembling a stamper (V-shaped, 90°, 5 μm pitch) to obtain a 32-inch prism diffusing plate having a thickness of 2 mm. Example 9 In addition to the use of the multi-branched macromonomer (Mm-4) obtained in Reference Example 4 in place of the multi-branched macromonomer (Mm-3) in Example 4, it was added relative to benzene (ethylene monomer). The amount was set to 1, and the styrene resin (A-5) was obtained in the same manner as in Example 4 except that 〇〇〇Ppm was added. 0.7 part of the light diffusing agent (B-1) was added to the obtained styrene system. In 100 parts of the resin (A-5), a roller was used for preliminary mixing, and the mixture was melt-mixed in the same manner as in Example 1 and supplied to the material for injection molding to obtain a 32-inch diffusion plate having a thickness of 2 mm. 1 〇 In addition to the multi-branched macromonomer (M m - 4 ) obtained in Reference Example 4, in place of the multi-branched macromonomer (Mm_3) in Example 4, the proceeding phase -34-200921152 is the same as in Example 4. The styrene resin (A-6) was obtained in the same manner. 0.7 part of the light diffusing agent (B-1) was added to 100 parts of the obtained styrene resin (A-6), and 0.1 part of ultraviolet absorption was added. Agent 1, 〇. 〇 3 parts of antioxidant 1, 0 · 0 7 parts of antioxidant 2, use a roller to prepare for mixing. The mixture was melt-mixed in the manner of Example 1, and supplied to the injection-molded material to obtain a 32-inch diffusion plate having a thickness of 2 mm. Example 1 1 Except that the multi-branched macromonomer (Mm-5) obtained in Reference Example 5 was used. A styrene resin (a _ 7 ) was obtained in the same manner as in Example 4 except that the multi-branched macromonomer (M m - 3 ) in Example 4 was replaced by f. 7 parts of the light diffusing agent were obtained. (B-1) is added to the obtained styrene resin (a_7) 1 part, and 0.1 part of the ultraviolet absorber 1, 〇. 〇 3 parts of the antioxidant 1, 0.0 7 parts of the antioxidant 2. Using a roller to prepare for mixing, the mixture was melt-mixed in the same manner as in Example 1 and supplied to the injection-molded material to obtain a 32-inch diffusion plate having a thickness of 2 mm. Comparative Example 1 ΐ..., except modulation A mixed solution of 94 parts of a styrene monomer and 6 parts of toluene is added to a styrene monomer in an amount of 30 〇ppm of a peroxybutyl butyl benzoate as an organic peroxide. The styrene resin (A '-1) was obtained in the same manner as in Example 4. 7 parts of the light diffusing agent (B-1) was added to the obtained styrene-based resin (1 part, using a drum to prepare for mixing. Performing the same manner as in Example 1 to melt-mix this mixture) was supplied. The molded material was injected to obtain a 32-inch diffusion plate. Comparative Example 2 -35- 200921152 A mixed solution of 94 parts of styrene monomer and 6 parts of toluene was prepared, and 200 ppm of 2 was added to the styrene monomer. 2-Bis(4,4-dibutylhexyl)peroxide, using the apparatus shown in Figure 1, continuous block polymerization according to the following conditions: Supply of mixed solution ····················· Reaction temperature of the reactor (2): 1 15 ° C, reaction temperature of the circulating polymerization line (I): 125 ° C, reaction temperature of the non-circulating polymerization line (II): 130 to 160 ° C, reflux ratio: R = F 1 / F 2 = 6. However, the F 1 system shows the flow rate of the mixed solution in the reflux cycle polymerization line, and the flow rate of the mixed solution in which the F 2 system does not flow to the non-circulating polymerization line. The mixed solution obtained by the polymerization was heated to 220 ° C under a reduced pressure of 50 mmHg by a heat exchanger to remove volatile components, and then granulated to obtain a styrene resin (A ′ - 2 ). To the obtained styrene resin (A ' - 2 ) 100 parts, 0.7 parts of the light diffusing agent (B-1) was added, and 1 part of the ultraviolet absorber 丨, 0.03 part of the antioxidant 1 was added. 0.0 7 parts of Antioxidant 2, premixed using a roller. Further, this mixture was mixed with a 3 Ommcp twin screw extruder to obtain nine particles. The obtained composite was preliminarily dried at 70 ° C for 3 hours, and a 3 2 吋 diffusion plate having a thickness of 2 m was formed by a 4500 ton injection molding machine. Comparative Example 3 A mixed solution of 74 parts of styrene monomer, 18 parts of methyl methacrylate and 8 parts of toluene was prepared, and 50 ppm was added as a peroxide for the total amount of styrene and methyl methacrylate. 2,2-bis(peroxy-4,4-dibutylhexyl)propane, using the apparatus shown in Figure 1, continuous block polymerization according to the conditions of -36-200921152 Supply: 9L / hr, stirred reactor (2) reaction temperature: 1 1 5 ° C, cycle polymerization line (I) reaction temperature: 1 2 0 ° C, non-circulating polymerization line (II) reaction temperature :1 2 5~1 5 0 X:, reflux ratio: R = F 1 / F 2 = 6. However, the 'F 1 system shows the flow rate of the mixed solution in the reflux cycle polymerization line, and the F 2 system shows the flow rate of the mixed solution flowing to the non-circulating polymerization line. The mixed solution obtained by the polymerization was heated by a heat exchanger to a reduced pressure of 50 °H under a reduced pressure of 50 mmHg, and then ninth granulated to obtain a styrene resin (A'-3). To 100 parts of the obtained styrene resin (A'-3), 0.7 part of a light diffusing agent (B-1) was added and premixed using a roll. The mixture was melt-mixed in the same manner as in Example 1 and supplied to the injection-molded material to obtain a 32-inch diffusion plate. Comparative Example 4 In the styrene resin (A ' - 2 ) 100 parts obtained in the same manner as in Comparative Example 2, the addition of 0.4 5 parts of the light diffusing agent (B -1 ) ' 0.1 part of ultraviolet rays Absorbent 1, 〇. 〇 3 parts of antioxidant 1, 〇 · parts of antioxidant 2, using a roller to prepare for mixing. This mixture was melt-mixed in the same manner as in Example 1 and injection-molded using a mold for assembling a stamper (V-shaped, 90 °, 5 Ομηι) to obtain a 32-inch prism diffusing plate having a thickness of 2 mm. Comparative Example 5 A bismuth resin-37-200921152 (A'-3) obtained in the same manner as in Comparative Example 3 was added, and 2 parts of a light diffusing agent (B-丨). Ultraviolet absorber 1, 0.03 parts of antioxidant 1, and part of the antioxidant 2' used a roller to prepare for mixing. The mixture was melt-mixed in the same manner as in Example 1 and injection-molded using a mold for assembling a stamper (v-word, 90°, 50 μm pitch) to obtain a 32-inch prism having a thickness of 2 mm. Diffuser plate. The evaluation results are summarized in Tables 1 to 11 and Comparative Examples 1 to 5' in Table-38-200921152 [Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Styrene resin A-1 A-2 Α·3 A-4 A-4 A-4 Giant monomer type Mm-1 Mm-2 Mm-3 Mm-3 Mm-3 Mm-3 Giant monomer Mw (xlO4) 6,000 3,900 3,000 3,000 3,000 3,000 macromonomer double bond content (mmol/g) 2.70 1.50 2.00 2.00 2.00 2.00 Giant monomer addition (ppm) 500 500 500 1,800 1,800 1,800 A Mw (xlO4) styrene resin 48 42 32 42 42 42 (Ρ2/Ρ1) 55/45 45/55 42/58 50/50 50/50 50/50 'The slope of the correlation diagram between the radius of anger and the molecular weight 0.36 0.39 0.40 0.35 0.35 0.35 Refractive index 1.59 1.59 1.59 1.59 1.59 1.59 MFR ( g/10min) 2.0 2.2 2.8 4.0 4.0 4.0 Type B-1 B-1 B-1 B-1 B-2 B-1 Particle size (μπι) 3.5 3.5 3.5 3.5 2.5 3.5 B Refractive index 1.43 1.43 1.43 1.43 1.51 1.43 Add Amount (wt%) 0.7 0.7 0.7 0.7 1.7 0.7 Add UV absorber 1 0.1 Add antioxidant 1 0.03 Agent antioxidant 2 0.07 Appearance and processability 0o 0 〇平Penetration rate (%) 67.11 63.38 62.38 65.50 67.42 63.33 Maximum penetration rate (%) 67.40 63.62 62.62 65.78 67.74 63.59 Minimum penetration rate (%) 66.87 63.09 62.05 65.25 67.20 63.01 Plate penetration unevenness (%) 0.8 0.8 0.9 0.8 0.8 0.9 Water absorption (%) 0.06 0.06 0.05 0.05 0.05 0.06 -39- 200921152 [Table 2] Example 7 Example 8 Example 9 Example 10 Example 11 Styrene resin A-4 A-4 A -5 A-6 A-7 Giant monomer _ Mm-3 Mm-3 Mm-4 Mm-4 Mm-5 Giant monomer Mw (xlO4) 3,000 3,000 5,200 5,200 7,900 Giant monomer double bond content (mmol/g) 2.00 2.00 3.00 3.00 2.90 Giant monomer addition (ppm) 1,800 1,800 1,000 1,800 1,800 A Mw (xlO4) of styrene resin 42 42 36 52 50 (Ρ2/Ρ1) 50/50 50/50 52/48 55/45 55/45 Slope of the relationship between the radius of inertia and the molecular weight 0.35 0.35 0.36 0.35 0.35 Refractive index 1.59 1.59 1.59 1.59 1.59 MFR (g/10min) 4.0 4.0 3.5 3.0 3.0 Type B-1 B-1 B-1 B-1 B- 1 Particle size (μηι) 3.5 3.5 3.5 3.5 3.5 B Refractive index 1.43 1.43 1.43 1.43 1.43 Adding amount (wt%) 0.45 0.2 0.7 0.7 0.7 Tim UV absorber 1 0.1 0.1 — 0.1 0.1 Antioxidant 1 0.03 0.03 A 0.03 0.03 Antioxidant 2 0.07 0.07 A 0.07 0.07 Pattern transfer 〇〇 — _ — Appearance and processability 扩 Extended average penetration (%) 74.42 84.61 64.11 62.95 63.94 Maximum penetration rate (%) 74.71 84.87 64.42 63.26 64.26 Minimum penetration rate of board (%) 74.18 84.22 63.88 62.69 63.69 Uneven penetration rate (%) 0.7 0.8 0.8 0.9 0.9 Water absorption rate ( %) 0.06 0.06 0.05 0.06 0.06 -40- 200921152 [Table 3] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Styrene resin AM A, -2 A'-3 A'-2 Α, - 3 Giant monomer macromonomer Mw (xlO4) Giant monomer double bond content (mmol/g) Giant monomer addition amount (ppm) A Styrene resin Mw (xlO4) 25 24 32 24 32 (Ρ2/Ρ1 0/100 0/100 0/100 0/100 0/100 Slope of correlation between inertia radius and molecular weight 0.52 0.50 0.50 0.50 0.50 Refractive index 1.59 1.59 1.57 1.59 1.57 MFR (g/10min) 3.0 2.0 1.4 2.0 1.4 Type B -1 B-1 B-1 B-1 B-1 Particle size (μπ 3.5 3.5 3.5 3.5 3.5 B Refractive index 1.43 1.43 1.43 1.43 1.43 Adding amount (wt%) 0.7 0.7. 0.7 0.45 0.2 Adding UV absorber 1 0.1 0.1 0.1 Adding antioxidant 1 0.03 0.03 0.03 Antioxidant 2 0.07 0.07 0.07 Pattern transfer Properties Δ X Appearance and processability 〇〇X 〇X Diffusion average penetration rate (%) 63.43 65.82 63.77 76.56 86.53 Maximum penetration rate (%) 63.85 66.32 64.00 76.09 87.20 Minimum penetration rate of board (%) 62.91 65.33 63.12 75.12 86.02 Unevenness of penetration rate (%) 1.5 1.5 1.4 1.3 1.4 Water absorption rate (%) 0.05 0.11 0.06 0.06 0.06 -41 - 200921152 From Tables 1 and 2, the resin composition for a light diffusing plate of the present invention and a resin composition thereof In addition to light diffusibility, the light diffusing plate also has excellent processability, low water absorption, and low unevenness in transmittance. [Industrial Applicability] The resin composition for a light-diffusing sheet of the present invention has excellent processability, and the obtained light-diffusing sheet has light diffusibility, low water absorption, and low transmittance unevenness, and can be particularly large. The light diffusing plate of the direct type backlight type in the liquid crystal display is utilized. In addition, the high workability of the resin composition f for a light-diffusing sheet of the present invention and the homogeneity of the composition can be simultaneously diffused by, for example, performing fine processing on the surface thereof to improve the light diffusing effect. Injection molding of sheet forming and surface processing. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a flow chart showing an example of a continuous polymerization line in which a tubular reactor having a static mixing element is assembled. Fig. 2 is a chromatogram of GPC-MALS of the styrene resin (A-3) obtained in Example 3. Fig. 3 is a two-log plot of the molecular weight and the radius of inertia of the styrene resin (A-3) determined by GPC-MALS. Further, a linear combination of a region having a molecular weight of 250,000 to 1, and a range of 〇·35 and 0.45 in the range is shown in Fig. 3 . [Main component symbol description] 1 Piston pump 2 Stirred reactor 3, 7 Gear pump 4~6, 8~1 0 Tubular reactor with static mixing element -42-

Claims (1)

200921152 * X. Patent application scope: 1 _ A resin composition for a light diffusing plate, which is a resin composition for a light diffusing plate containing a styrene resin (A) and a light diffusing agent (B), and is characterized in that: The styrene-based resin (A) contains a plurality of branches, and a multi-branched macromonomer (al) having a plurality of polymerizable double bonds at its tip end is copolymerized with a styrene monomer (a2). Resin. 2. The resin composition for a light-diffusing sheet according to the first aspect of the invention, wherein the styrene-based resin (A)/(1) has a weight average molecular weight of 150,000 to 55 by the GPC-MALS method. (2) The two-logarithmic graph in which the molecular weight determined by the GPC-MALS method is the horizontal axis and the radius of inertia is the vertical axis is 0.35 to 0.45 in the region of the molecular weight of 250,000 to 10,000,000. A light diffusing plate characterized by being composed of a resin composition as claimed in claim 1 or 2. A method of producing a light diffusing sheet, which is characterized by injection molding a resin composition as disclosed in claim 1 or 2. -43-