A photocurable material formulation for a lost model that has a high elastic modulus, shows small thermal expansion, has heat resistance in a certain temperature region, and is free of a photoacid generator to be used in an epoxy material or the like. The formulation is a photocurable composition including curable materials formed of monofunctional (meth)acrylates each having a molecular weight of 150 or more and less than 350, and a bifunctional (meth)acrylate having a molecular weight of 200 or more and less than 400.

A polymer comprising repeating units derived from a first monomer, typically acrylonitrile, and repeating units derived from a second monomer different from the first monomer, wherein the second monomer is a compound comprising an ethylenically unsaturated organic anion and an organic cation containing a C═N imine group; a process for producing carbon fibers using the said polymer; and carbon fibers made therefrom, are described herein.

A composition comprising a compound (A) represented by formula (I):

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wherein R.sup.1 and R.sup.2 each independently represent any one selected from the group consisting of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, an alkenyl group having 2 to 6 carbon atoms, an aryl group, and an aralkyl group;
R.sup.3 represents any one selected from the group consisting of a (meth)acryloyl group, a 4-vinylphenyl group, and an alkenyl group having 2 to 6 carbon atoms;
and n represents an integer of 0 to 5,
and a polyfunctional compound (B) other than the compound (A) is excellent in the curability because the composition sufficiently polymerizes even in the presence of oxygen, for example, in an air atmosphere.

A positive resist composition comprising a base polymer comprising recurring units having a carboxyl group whose hydrogen is substituted by a pyridine ring-containing tertiary hydrocarbyl group.

A positive resist composition comprising a base polymer comprising recurring units having a carboxyl group whose hydrogen is substituted by a pyridine ring-containing tertiary hydrocarbyl group.

A resist composition comprising a base polymer and an acid generator containing a sulfonium salt having the formula (1) or an iodonium salt having the formula (2).

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A resist composition comprising a base polymer and an acid generator containing a sulfonium salt having the formula (1) or an iodonium salt having the formula (2).

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A radiation-sensitive resin composition includes: a polymer including a first structural unit represented by formula (1); and a radiation-sensitive acid generator. In the formula (1), R.sup.1 represents a hydrogen atom, a fluorine atom, a methyl group, or a trifluoromethyl group; R.sup.2, R.sup.3, and R.sup.4 each independently represent a hydrogen atom or a monovalent organic group having 1 to 20 carbon atoms; R.sup.5 represents a monovalent organic group having 1 to 20 carbon atoms; and L represents a single bond or a divalent organic group having 1 to 20 carbon atoms.

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An aqueous thickener blend composition comprising an aqueous hydrophobically-modified alkali soluble or alkali swellable thickener composition and an acid-suppressible associative thickener composition, affording high thickening efficiency and providing an aqueous coating composition comprising such aqueous thickener blend composition with good heat-age stability and color float stability.

A resist composition including a resin component having a constitutional unit derived from a compound represented by General Formula (a01-1) and a constitutional unit derived from a compound represented by General Formula (a02-1), and an acid generator component composed of an anion moiety and a cation moiety. In General Formula (a01-1), W.sup.1 represents a polymerizable group-containing group, C.sup.t represents a tertiary carbon atom, R.sup.11 represents an unsaturated hydrocarbon group which may have a substituent, R.sup.12 and R.sup.13 represent a chain saturated hydrocarbon group which may have a substituent, and a carbon atom at an α-position of C.sup.t constitutes a carbon-carbon unsaturated bond. In General Formula (a02-1), W.sup.2 represents a polymerizable group-containing group, Wa.sup.2 represents an aromatic hydrocarbon group, and n2 represents an integer in a range of 1 to 3

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