Abstract: The invention provides: a dihydroxynaphthalene condensate which suppresses soft particle generation and is suitably usable for a composition excellent in filterability; and a method for producing the dihydroxynaphthalene condensate. In the method for producing a dihydroxynaphthalene condensate, dihydroxynaphthalene to be used has a sulfur element content of 100 ppm or less in terms of mass among constituent elements. The dihydroxynaphthalene and a condensation agent are condensed in presence of an acid or a base to produce the dihydroxynaphthalene condensate.

Abstract: The invention provides: a dihydroxynaphthalene condensate which suppresses soft particle generation and is suitably usable for a composition excellent in filterability; and a method for producing the dihydroxynaphthalene condensate, in the method for producing a dihydroxynaphthalene condensate, dihydroxynaphthalene to be used has a sulfur element content of 100 ppm or less in terms of mass among constituent elements. The dihydroxynaphthalene and a condensation agent are condensed in presence of an acid or a base to produce the dihydroxynaphthalene condensate.

Abstract: The invention provides a method for purifying dihydroxynaphthalene, which is capable of suppressing soft particle generation and obtaining dihydroxynaphthalene serving as a raw material of a resin and composition excellent in filterability. The method for purifying dihydroxynaphthalene includes the step of removing a sulfur content in the dihydroxynaphthalene with an adsorbent, and neutral alumina is used as the adsorbent.

Abstract: A curable resin including a repeating unit of hydroxystyrene substituted with an alkoxymethyl group, the repeating unit represented by the following general formula (1): where Ra represents a hydrogen atom or a methyl group; Rb represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; m is 1 to 3; and n is 1 to 3.

Abstract: There is provided a water treatment method using a water treatment flocculant that suffers from minimal secondary contamination with flocculation residues and contains an alkaline solution of a phenolic resin. A water treatment method involving the addition of a flocculant to water to be treated and subsequent membrane separation treatment. The flocculant contains an alkaline solution of a phenolic resin having a melting point in the range of 130° C. to 220° C. The water treatment flocculant is produced by a resole-type second-order reaction in the presence of an alkaline catalyst in which an aldehyde is added to an alkali solution of a novolak phenolic resin. The novolak phenolic resin is produced by a reaction between a phenol and an aldehyde in the presence of an acid catalyst.

Abstract: A curable resin including a repeating unit of hydroxystyrene substituted with an alkoxymethyl group, the repeating unit represented by the following general formula (1): where Ra represents a hydrogen atom or a methyl group; Rb represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms; m is 1 to 3; and n is 1 to 3.

Abstract: There is provided a water treatment method using a water treatment flocculant that suffers from minimal secondary contamination with flocculation residues and contains an alkaline solution of a phenolic resin. A water treatment method involving the addition of a flocculant to water to be treated and subsequent membrane separation treatment. The flocculant contains an alkaline solution of a phenolic resin having a melting point in the range of 130° C. to 220° C. The water treatment flocculant is produced by a resole-type second-order reaction in the presence of an alkaline catalyst in which an aldehyde is added to an alkali solution of a novolak phenolic resin. The novolak phenolic resin is produced by a reaction between a phenol and an aldehyde in the presence of an acid catalyst.

Abstract: There is provided a process for preparing a polymer compound for a resist, which can improve the performance, such as the heat resistance, sensitivity and resolution of the resist, without causing film loss of the resist, line width reduction of the resist or deterioration of the dry etching resistance of the polymer. This process comprises dissolving a styrene-based monomer containing at least a 4-acetoxystyrene monomer, and a dimethyl-2,2′-azobiscarboxylate ester in a solvent, thereby to polymerize the styrene-based monomer; adding an alkali catalyst to the resulting polymer solution, thereby to hydrolyze the polymer solution; and washing the resulting polymer compound with water.

Abstract: The present invention relates to a novolak type phenol resin, in particular a novolak type phenol resin for resists suitable for forming resist patterns. The novolak type phenol resin of the present invention is obtained by reacting at least a vinylphenol having a vinyl group and a phenolic hydroxyl group, such as parahydroxystyrene, or a polyvinylphenol, which is a polymer of the vinylphenol, a compound (A) such as 4,4′-methylenebis(2-hydroxymethyl-3,6-dimethylphenol) and/or a compound (B) such as 2,6-dihydroxymethyl-4-phenol, in a ratio of 1 to 40 moles of the compound (A) and/or compound (B) to 100 moles of the vinylphenol or 100 moles of structural unit of the vinylphenol contained in the polyvinylphenol in the presence of an acid and having a weight average molecular weight of 2,000 to 20,000. Such a novolak type phenol resin provides good pattern shape, heat resistance, resolution, and sensitivity in resists for lithography.

Abstract: The present invention relates to a phenol resin, in particular a phenol resin for resists suitable for forming resist patterns. The phenol resin of the present invention is obtained by reacting at least two components, i.e., a compound (A) such as 4-hydroxymethyl-2,6-dimethylphenol and a polymerizable phenol compound such as parahydroxystyrene or a polymer (B), which is a polymer of the polymerizable phenol compound, in a ratio of 1 to 50 moles of the compound (A) to 100 moles of the polymerizable phenol compound or 100 moles of structural unit of the polymerizable phenol compound contained in the polymer (B) in the presence of an acid and having a molecular weight of 2,000 to 20,000. Such a phenol resin provides good pattern shape, heat resistance, resolution, and sensitivity in resists for lithography.