Abstract: Disclosed herein are a stamper which has anodized alumina formed on the surface thereof and which will not cause macroscopic unevenness or color unevenness on the transcribed surface; a method for producing the same; and a method for producing a molded material without macroscopic unevenness or color unevenness on the transcribed surface thereof by using such a stamper. The stamper includes alumina which has a microasperity structure and which is formed by anodization on the surface of a prototype aluminum mold having an aluminum purity of 99.5% or more, an average crystal-grain diameter of 1 mm or less, and an arithmetic mean surface roughness Ra of 0.05 ?m or less. The use of this stamper enables the production of a molded material which does not have macroscopic unevenness or color unevenness on the transcribed surface thereof and which is suitable for use as an antireflection article and the like.

Abstract: Disclosed herein are a stamper which has anodized alumina formed on the surface thereof and which will not cause macroscopic unevenness or color unevenness on the transcribed surface; a method for producing the same; and a method for producing a molded material without macroscopic unevenness or color unevenness on the transcribed surface thereof by using such a stamper. The stamper includes alumina which has a microasperity structure and which is formed by anodization on the surface of a prototype aluminum mold having an aluminum purity of 99.5% or more, an average crystal-grain diameter of 1 mm or less, and an arithmetic mean surface roughness Ra of 0.05 ?m or less. The use of this stamper enables the production of a molded material which does not have macroscopic unevenness or color unevenness on the transcribed surface thereof and which is suitable for use as an antireflection article and the like.

Abstract: A copolymer having low birefringence substantially consisting of a repeating unit represented by the following general formula (1) and a repeating unit of a (meth)acrylate: wherein, R1 represents a hydrogen atom or a hydrocarbon group having 1 to 25 carbon atoms, an alicyclic hydrocarbon group or a substituted hydrocarbon group.). This copolymer has low birefringence and low hydrophilia, is excellent in transparency, heat-resistance and mechanical strength, and can be applied to lenses, optical disks, optical fibers and the like.

Abstract: Disclosed is a process for the preparation of a poly-(meth)acrylate ester, which comprises, upon polymerization of a (meth)acrylate ester by using an organometallic compound ((C.sub.5 Me.sub.5).sub.2 SmMe(thf) or the like) having at least one polymerization initiating site, carrying out the polymerization in the presence of a compound (acetophenone, 4-methyl-2-pentanone or the like), which contains in the molecule thereof a reactive hydrogen atom, as a chain transfer agent. The above-described process makes it possible to control the molecular weight easily, reduce the using amount of the organometallic compound, prevent the coloring of the poly(meth)acrylate ester and improve thermal decomposition resistance.

Abstract: An A-B-A type of block copolymer consisting of polymer block A of (meth)acrylate and polymer block B of olefin, having a Mw/Mn of 1.0 to 2.5, is disclosed. This block copolymer can be produced by polymerizing an olefin using a particular rare earth compound as an initiator, and then polymerizing the formed polymer with a (meth)acrylate.

Abstract: A method for preparing a graft copolymer is here disclosed which is characterized by comprising the step of carrying out a living polymerization of at least one (meth)acrylic ester by the use of a polymeric compound as an initiator having one or more units represented by the following formula (I) in a molecular chain substantially in the absence of water in the presence of a Lewis acid or a donor compound of an anion selected from the group consisting of HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- and F.sup.- : ##STR1## wherein R is hydrogen or an alkyl group having 1 to 6 carbon atoms, and R' is an alkyl group having 1 to 12 carbon atoms.

Abstract: A preparation process of block copolymers which comprises conducting living polymerization of a (meth)acrylic ester substantially in the absence of water, by using a macromolecular compound having a functional end group represented by the formula (1): ##STR1## Wherein R is H or an n-alkyl group having from 1 to 3 carbon atoms and R' is H or an alkyl group having from 1 to 6 carbon atoms, as a polymerization initiator and in the presence of a Lewis acid or in the presence of a donor compound of an anion selected from HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- or F.sup.-, as well as novel block copolymers prepared therefrom are disclosed.

Abstract: The present invention provides shaped articles having good transparency and high oxygen permeability in a specific direction thereof, which have been made from a block copolymer (a) composed of a polyalkyl methacrylate segment and a silicone-based polymethacrylate segment, or a block copolymer (b) or graft copolymer (c) containing a polyorganosiloxane as one component, according to a process permitting the creation of a specific higher-order structure. These shaped articles have high oxygen permeability at relatively low silicone contents and, therefore, can provide oxygen-permeable products having high tear strength and surface hardness.

Abstract: An antistatic agent capable of imparting a permanent antistatic property to a methacrylic resin is prepared as follows. First, an alkyl methacrylate is subjected to living polymerization in an atmosphere substantially free of water in the pressure of at least one compound acting as a source for supplying an anion selected from HF.sub.2.sup.-, (CH.sub.3).sub.3 SiF.sub.2.sup.- and F.sup.- by using as an initiator a compound represented by the formula (I) or (II): ##STR1## wherein R is H or CH.sub.3 and R.sup.1 is H or alkyl; second, a methacrylic acid ester comprising at least 80 mole % of a methacrylic acid ester represented by the formula (III): ##STR2## wherein R.sup.2 is alkyl and m is from 1 to 6, is subjected to living polymerization in the presence of the polymer obtained in the first step, to prepare a di-block or tri-block copolymer; and then, amino groups of segments derived from the methacrylic acid ester of the formula (III) in the block copolymer are quaternized.

Abstract: A comb copolymer consisting of a methacrylic macromonomer as a branch ingredient and acrylic ester as a backbone ingredient and being suitable for an acrylic elastomer material which is excellent in transparency, weatherability and mechanical strength; an impact resistant acrylic resin composition obtained by blending the above comb copolymer with a PMMA (co)polymer; and a comb copolymer similarly consisting of a methacrylic macromonomer as a branch component and acrylic ester as a backbone component and being an acrylic resin which is excellent in transparency, weatherability, gloss and light resistance, are disclosed in this invention.Preparation methods of the high molecular weight comb copolymers useful for molding materials comprising the above mentioned comb copolymers are disclosed.

Abstract: A comb copolymer consisting of a methacrylic macromonomer as a branch ingredient and acrylic ester as a backbone ingredient and being suitable for an acrylic elastomer material which is excellent in transparency, weatherability and mechanical strength; an impact resistant acrylic resin composition obtained by blending the above comb copolymer with a PMMA (co)polymer; and a comb copolymer similarly consisting of a methacrylic macromonomer as a branch component and acrylic ester as a backbone component and being an acrylic resin which is excellent in transparency, weatherability, gloss and light resistance, are disclosed in this invention.Preparation methods of the high molecular weight comb compolymers useful for molding materials comprising the above mentioned comb copolymers are disclosed.