Abstract: Disclosed are a volume phase hologram recording material having high sensitivity, high contrast, and excellent multiple recording and record holding properties and a volume phase hologram recording medium using the same. The volume phase hologram recording material comprises mainly a polymer matrix (a), a radically photopolymerizable compound (b), and a radical photopolymerization initiator (c) and the polymer matrix is a three-dimensionally crosslinked or linear polymer matrix formed from a polymer matrix-forming material containing 0.5-50 wt % of an episulfide compound (f), an epoxy compound (g), and a curing agent (h).

Abstract: Disclosed is a volume phase hologram recording material characterized by excellent photosensitivity, low cure shrinkage, high transparency, and particularly good storage stability and also disclosed is a recording medium prepared therefrom. Further disclosed is a photosensitive resin composition for volume phase hologram recording that comprises a soluble aromatic copolymer (A), a photoradically polymerizable compound (B) capable of copolymerizing with the soluble aromatic copolymer (A), a photopolymerization initiator (C), and a polymer binder (D). The soluble aromatic copolymer (A) has a structural unit of a divinyl aromatic compound and a structural unit of a monovinyl aromatic compound, comprises 10 to 90 mol % of a structural unit represented by the following formula (a1), has a hydroxyl equivalent of 100 to 30,000 g/equiv, a number average molecular weight (Mn) of 400 to 30,000, and a molecular weight distribution (Mw/Mn) of 10 or less, and accounts for 5 to 60 wt % of the composition.

Abstract: The present invention relates to a volume phase hologram recording material excellent in transparency, sensitivity, low curing shrinkage, and transparency, a volume phase hologram recording medium, and a volume phase hologram. A photosensitive resin composition for volume phase hologram recording contains a low-molecular-weight solvent-soluble aromatic copolymer (A) having a structural unit of a divinyl aromatic compound and a structural unit of a monovinyl aromatic compound, a photoradical polymerizable compound (B) which is copolymerizable with the soluble aromatic copolymer (A), and a photopolymerization initiator (C) as essential components. The photosensitive resin composition further contains, one kind or more of a polymer binder (D) and a plasticizer (E), and the soluble aromatic copolymer (A) is incorporated in an amount of 5 to 60% by weight.

Abstract: Disclosed are a volume phase hologram recording material having high sensitivity, high contrast, and excellent multiple recording and record holding properties and a volume phase hologram recording medium using the same. The volume phase hologram recording material comprises mainly a polymer matrix (a), a radically photopolymerizable compound (b), and a radical photopolymerization initiator (c) and the polymer matrix is a three-dimensionally crosslinked or linear polymer matrix formed from a polymer matrix-forming material containing 0.5-50 wt % of an episulfide compound (f), an epoxy compound (g), and a curing agent (h).

Abstract: Provided is curable resin composition which gives a cured article excellent in chemical resistance, dielectric properties, low water-absorption, heat resistance, flame retardance, and mechanical properties and which is usable in applications such as dielectric materials, insulating materials, heat-resistant materials, and structural materials. The curable resin composition includes a component (A) which is a polyphenylene ether oligomer having a number-average molecular weight of 700 to 4,000 and having a vinyl group at both end and a component (B) which is a solvent-soluble polyfunctional vinylaromatic copolymer which has structural units derived from monomers including a divinylaromatic compound (a) and an ethylvinylaromatic compound (b) and in which the content of repeating units derived from the divinylaromatic compound (a) is 20 mol % or higher, the ratio of the amount (wt. %) of the component (A) to that (wt. %) of the component (B) being (20 to 98):(2 to 80).

Abstract: Disclosed is a volume phase hologram recording material characterized by excellent photosensitivity, low cure shrinkage, high transparency, and particularly good storage stability and also disclosed is a recording medium prepared therefrom. Further disclosed is a photosensitive resin composition for volume phase hologram recording that comprises a soluble aromatic copolymer (A), a photoradically polymerizable compound (B) capable of copolymerizing with the soluble aromatic copolymer (A), a photopolymerization initiator (C), and a polymer binder (D). The soluble aromatic copolymer (A) has a structural unit of a divinyl aromatic compound and a structural unit of a monovinyl aromatic compound, comprises 10 to 90 mol % of a structural unit represented by the following formula (a1), has a hydroxyl equivalent of 100 to 30,000 g/equiv, a number average molecular weight (Mn) of 400 to 30,000, and a molecular weight distribution (Mw/Mn) of 10 or less, and accounts for 5 to 60 wt % of the composition.

Abstract: The present invention relates to a volume phase hologram recording material excellent in transparency, sensitivity, low curing shrinkage, and transparency, a volume phase hologram recording medium, and a volume phase hologram. A photosensitive resin composition for volume phase hologram recording contains a low-molecular-weight solvent-soluble aromatic copolymer (A) having a structural unit of a divinyl aromatic compound and a structural unit of a monovinyl aromatic compound, a photoradical polymerizable compound (B) which is copolymerizable with the soluble aromatic copolymer (A), and a photopolymerization initiator (C) as essential components. The photosensitive resin composition further contains, one kind or more of a polymer binder (D) and a plasticizer (E), and the soluble aromatic copolymer (A) is incorporated in an amount of 5 to 60% by weight.

Abstract: Provided is curable resin composition which gives a cured article excellent in chemical resistance, dielectric properties, low water-absorption, heat resistance, flame retardance, and mechanical properties and which is usable in applications such as dielectric materials, insulating materials, heat-resistant materials, and structural materials. The curable resin composition includes a component (A) which is a polyphenylene ether oligomer having a number-average molecular weight of 700 to 4,000 and having a vinyl group at both end and a component (B) which is a solvent-soluble polyfunctional vinylaromatic copolymer which has structural units derived from monomers including a divinylaromatic compound (a) and an ethylvinylaromatic compound (b) and in which the content of repeating units derived from the divinylaromatic compound (a) is 20 mol % or higher, the ratio of the amount (wt. %) of the component (A) to that (wt. %) of the component (B) being (20 to 98):(2 to 80).

Abstract: This invention relates to a process for preparing rubber-modified aromatic vinyl resin compositions by polymerizing a raw material solution containing 3 to 20% by weight of rubbery polymer, 50 to 97% by weight of an aromatic vinyl monomer, and 0 to 30% by weight of a solvent until the conversion of said aromatic vinyl monomer falls in the range from 30 to 70%, adding a (meth)acrylate monomer or its mixture with other monomers to the reaction mixture so that the ratio by weight of the aromatic vinyl monomer in the reaction mixture to the (meth)acrylate monomer becomes 85/15 to 50/50, continuing the polymerization, and devolatilizing to remove the unreacted monomers, solvent, and the like. It is possible by this process to prepare easily and economically rubber-modified aromatic vinyl resin compositions of easy processability, good surface properties in respect to appearance and scratch resistance, and good balance between impact resistance and rigidity.

Abstract: Provided is a rubber-modified aromatic vinyl resin composition, wherein(a) 4 to 20% by weight of a rubber-like polymer is contained,(b) the rubber-like polymer is dispersed in the aromatic vinyl polymer in the form of grains, and the dispersed grains have a weight-average grain diameter falling in a range of 0.4 to 0.8 .mu.m,(c) the dispersed grains have 1.0 .mu.m or less of a 5% value and 0.2 .mu.m or more of a 95% value in a cumulative grain diameter distribution on a weight basis,(d) a ratio of toluene-insoluble matters to a rubber component each of which is contained in the said composition falls in a range of 1.0 to 2.5, and(e) 0.005 to 0.5% by weight of a silicone oil or the mixed oil of the same amount of silicone oil and a fluorine compound oil of 0.0002 to 0.03% by weight is contained in the said composition. The rubber-modified aromatic vinyl resin composition described above is excellent in a balance between an impact resistance and a rigidity, and has an excellent gloss.

Abstract: Rubber-modified styrenic resin compositions of this invention comprise 90 to 30% by weight of rubber-modified styrenic resins (A) containing rubbery polymers dispersed with an average particle diameter of 0.3 to 2.0 .mu.m in the phase of styrenic polymers (C) and 10 to 70% by weight of styrene-(meth)acrylate ester copolymer resins (B) and, in said compositions, the content of (meth)acrylate ester units is 5 to 50% by weight and the toluene-insolubles (% by weight: X) and the rubber component (% by weight: Y) are present at a ratio (X/Y) in the range from 1.2 to 3.5. The compositions excel in appearance, scratch resistance, impact resistance and rigidity and are easy to fabricate.

Abstract: A rubber-modified styrenic resin composition obtained by graft-polymerizing a styrenic monomer dissolving a rubber-like polymer, wherein(1) the rubber-like polymer is dispersed in a styrenic polymer matrix in the form of particles having a volume average particle diameter falling in the range of 0.5 to 1.6 .mu.m,(2) the dispersed particles of said rubber-like polymer are of a salami structure in which a part of the styrenic polymer having a number average particle diameter falling in the range of 0.13 .mu.m or more and up to 0.20 .mu.m and a particle diameter distribution falling in the range of 1.15 to 1.35 is dispersed and included in the rubber-like polymer particles, and(3) the dispersed particles of said rubber-like polymer have a swelling ratio falling in the range of 7 to 12 in toluene.The rubber-modified styrenic resin composition of the present invention is excellent in mechanical strength, a gloss and a coloring property and has a good balance between them.

Abstract: An object of the present invention is to provide a process for producing rubber-modified styrene resins in which a distribution of the diameters of the rubber particles is narrow and the impact resistance is well balanced with the elastic modulus. The constitution thereof is characterized in that an aromatic monovinyl series monomer, a rubbery polymer and a styrene polymer are mixed and dissolved, and the mixed solution is adjusted so that the relation of the content R (wt. %) of the rubbery polymer contained in said mixed solution with the content Ps (wt. %) of the styrene polymer satisfies 0.2<Ps/R<3; the solution is further subjected to pre-heating treatment to maintain the conditions before rubber phase inversion, and then rubber phase inversion is carried out in a plug flow type reactor followed by polymerizing to enhance the polymerization conversion rate in the following plug flow type reactor.