Abstract: To provide an optical recording medium excellent in the balance of characteristics, which has a sufficient surface hardness and of which the deformation when the environmental temperature and the environmental humidity change is small. An optical recording medium comprising a resin substrate, a recording and reading layer, a cover coat layer which is a cured product of a radiation-curable composition containing a urethane (meth)acrylate (A) and a (meth)acrylate compound (B) other than the urethane (meth)acrylate (A), and a hard coat layer having a surface hardness of at least B in this order, wherein of the cover coat layer, the ratio of the elastic modulus in tension upon absorbing water to saturation to the elastic modulus in tension at 25° C. under a humidity of 45% is at least 0.20.

Abstract: A composition, etc. are provided, which can enhance hardness and afford abrasion resistance even in a thin film as well as excellent antifouling property and durability of the antifouling property. An organic polymer, is provided, which comprises 5 to 30 weight percent of a radical polymerizable monomer having a perfluoroalkyl group, 0.01 to 5 weight percent of ?,?-dimercaptopolysiloxane, 5 to 40 weight percent of a radical polymerizable monomer having a cationic photo polymerizable epoxy group, and 25 to 75 weight percent of the other radical polymerizable monomer copolymerizable therewith, said organic polymer having a structure corresponding to a radical polymerizable copolymer of a mixture of the monomers in which a molar ratio of the mercapto group to the epoxy group is 0.0001 to 0.025, and/or a structure obtained by reacting the epoxy groups of the radical polymerizable copolymer with (meth) acrylic acid.

Abstract: Disclosed is a composition capable of imparting high hardness, abrasion resistance, excellent contamination resistance and durability of such contamination resistance even in the form of a thin film. Specifically disclosed is a composition including an organic polymer containing 5-30% by mass of a radically polymerizable monomer with a perfluoroalkyl group, 0.01-5% by mass of ?,?-dimercaptopolysiloxane, 5-40% by mass of a radically polymerizable monomer with a cationically photopolymerizable epoxy group and 25-75% by mass of another radically polymerizable monomer which is copolymerizable with the aforementioned substances. The organic polymer has a structure corresponding to a radically polymerized copolymer of the monomer mixture wherein the molar ratio of the mercapto group to the epoxy group is 0.0001-0.025 and/or a structure obtained by reacting a (meth)acrylic acid with the epoxy group of the radically polymerized copolymer.

Abstract: To provide an optical recording medium excellent in the balance of characteristics, which has a sufficient surface hardness and of which the deformation when the environmental temperature and the environmental humidity change is small. An optical recording medium comprising a resin substrate, a recording and reading layer, a cover coat layer which is a cured product of a radiation-curable composition containing a urethane (meth)acrylate (A) and a (meth)acrylate compound (B) other than the urethane (meth)acrylate (A), and a hard coat layer having a surface hardness of at least B in this order, wherein of the cover coat layer, the ratio of the elastic modulus in tension upon absorbing water to saturation to the elastic modulus in tension at 25° C. under a humidity of 45% is at least 0.20.

Abstract: An active energy ray-curable antistatic coating composition contains (A) inorganic oxide fine particles having a side chain having a molecular weight of at least 300 and having a functional group and (B) an antistatic agent containing at least a quaternary ammonium salt group-containing polymer, a quaternary ammonium salt group-containing silane coupling agent and/or a hydrolysis condensate of the silane coupling agent, and optionally contains (C) a polyfunctional (meth)acrylate having at least 3 (meth)acryloyl groups in a molecule.

Abstract: An active energy ray-curable antistatic coating composition contains (A) inorganic oxide fine particles having a side chain having a molecular weight of at least 300 and having a functional group and (B) an antistatic agent containing at least a quaternary ammonium salt group-containing polymer, a quaternary ammonium salt group-containing silane coupling agent and/or a hydrolysis condensate of the silane coupling agent, and optionally contains (C) a polyfunctional (meth)acrylate having at least 3 (meth)acryloyl groups in a molecule.

Abstract: Copolymers are disclosed of lower alpha-olefins and HALS-containing monomers, typically 1-(10-undecenyl)-2,2,6,6-tetramethylpiperidine. They may be used for light or heat stabilizing, by themselves or in blends with other polymers.

Abstract: An aromatic polythioetherimide is disclosed, which comprises at least 50 mol % of a repeating unit represented by formula (I): ##STR1## wherein Ar is as defined in the specification, with the total of the repeating unit(s) being 100 mol %. The polythioetherimide has an excellent balance between heat resistance and mechanical properties as well as improved moldability.

Abstract: An aromatic polythioetherimide having a recurring unit of the following general formula (II): ##STR1## wherein --Ar--, which may be the same or different in the polymer, each represents a divalent aromatic residue and ##STR2## which may be the same or different in the polymer, each represents ##STR3## The aromatic polythioetherimides can be melt-molded, are excellent in the balance of mechanical properties and heat resistance, and can be widely used for parts in the electric and electronic fields, housings, automobile parts, aircraft interior parts, sliding parts, gears, cams, insulating materials, heat-resistant films, heat-resistant varnishes, heat-resistant fibers, etc., and preferably can be used as an engineering plastic for gears, cams, etc., and a heat-resistant insulating film material for electronic hardwares.

Abstract: An aromatic polythioetheramide-imide having a recurring unit of the following general formula (II): ##STR1## wherein --Ar--, which may be the same or different in the polymer, each represents a divalent aromatic residue. The aromatic polythioetheramide-imides are excellent in the balance of mechanical properties, heat resistance and moldability and can be used widely for parts in electric and electronic fields, housings, automobile parts, aircraft interior parts, sliding parts, gears, insulating materials, heat-resistant films, heat-resistant varnishes, heat-resistant fibers, etc.

Abstract: Aromatic polythioetheramide polymers having a repeating unit represented by the formulae as shown below and a process for the production thereof are described. These polymers have excellent moldability, flame retardance, heat resistance, and chemical resistance, and are suitable for use as engineering plastics: ##STR1## wherein all the symbols are the same as defined in the specification and claims.