Abstract: The invention relates to a dispersant for hydraulic composition, wherein 2 kinds of copolymers containing, as structural units, a polyalkylene glycol (meth)acrylate monomer (a) having the average number of moles of added alkylene oxide in a specific range and a specific unsaturated monomer (b) in a specific ratio are used such that the product of the average number of moles of added alkylene oxide and the acid-type converted wt % of (b) relative to the sum total of (a) and (b) are used in specific relationship.

Abstract: Disclosed is a powdery rheology modifier containing an anionic aromatic compound, a cationic surfactant, and an inorganic powder having a specific surface area of 5000 cm2/g or more.

Abstract: Disclosed is a powdery rheology modifier containing an anionic aromatic compound, a cationic surfactant, and an inorganic powder having a specific surface area of 5000 cm2/g or more.

Abstract: The present invention relates to a hydraulic composition dispersant containing a polycarboxylic acid-based polymer A having a carboxylic acid group and an oxyalkylene group and/or an oxystyrene group such as polymers obtained by copolymerizing a specified monomer 1 such as an ethylenic unsaturated carboxylic acid derivative having a polyoxyalkylene group with a specified monomer 2 such as a (meth)acrylic acid, and a polymer B obtained by copolymerizing the monomer 1, a monophosphate-based monomer 3 and a diphosphate-based monomer 4.

Abstract: The invention relates to a dispersant for hydraulic composition, wherein 2 kinds of copolymers containing, as structural units, a polyalkylene glycol(meth)acrylate monomer (a) having the average number of moles of added alkylene oxide in a specific range and a specific unsaturated monomer (b) in a specific ratio are used such that the product of the average number of moles of added alkylene oxide and the acid-type converted wt % of (b) relative to the sum total of (a) and (b) are used in specific relationship.

Abstract: The invention provides a process capable of easily producing a water-soluble salt of a naphthalenesulfonate formaldehyde condensate with a reduced amount of unreacted formaldehyde. When naphthalenesulfonic acid is subjected to condensation reaction with formaldehyde to produce a naphthalenesulfonate formaldehyde condensate, a sulfite is added to the reaction system after the conclusion of the condensation reaction. When a cement dispersant composition is obtained, the process includes a step of neutralizing the condensate.

Abstract: An dispersant for plaster comprising a copolymer prepared by copolymerizing (a) a polyalkylene glycol monoester monomer having 2 to 300 mols of an oxyalkylene group(s) each having 2 to 3 carbon atoms, with (b) at least one monomer selected from among acrylic monomers, unsaturated dicarboxylic monomers and allylsulfonic monomers. When the dispersant of the present invention is used in preparing a plaster board, the foam stability is maintained so that the quality of the plaster board composition can be easily controlled.

Abstract: A polysaccharide derivative prepared by replacing all or part of the hydroxyl hydrogen atoms of a polysaccharide or polysaccharide derivative by (A) a hydrophobic substituent having a C.sub.8 -C.sub.43 hydrocarbon chain as the partial structure and (B) an ionic hydrophilic substituent having at least one member selected from the group consisting of sulfonic, carboxyl phosphoric, and sulfate groups and salts thereof as the partial structure, wherein the average degree of replacement by the substituent (A) is 0.0001 or above but below 0.001 per constituent monosaccharide residue as determined by Zeisel's method or the diazomethane method and that by the substituent (B) is 0.01 to 2.0 per constituent monosaccharide residue as determined by colloidal titration. This polysaccharide derivative is useful as the admixture for hydraulic materials and can give stable hydraulic compositions excellent in dispersion.

Abstract: A concrete admixture is provided, which is effective in imparting fluidity to a hydraulic composition such as cement paste, mortar or concrete, particularly in maintaining the fluidity of the composition and which hardly retards the hardening property of the composition. The concrete admixture comprises a copolymer comprising, as structural units, units derived from an ethylenically unsaturated monomer (a) having 25 to 300 moles of C.sub.2 -C.sub.3 oxyalkylene groups per mole of copolymer and units derived from a monomer (b) of an alkyl, alkenyl or hydroxyalkyl ester of an ethylenically unsaturated mono- or di-carboxylic acid.

Abstract: An admixture for concrete comprising, as an essential component, a copolymer prepared by copolymerizing (a) a polyalkylene glycol monoester monomer having 110 to 300 mols of an oxyalkylene group(s) each having 2 to 3 carbon atoms, with (b) at least one monomer selected from among acrylic monomers, unsaturated dicarboxylic monomers and allylsulfonic monomers. When this admixture is used in preparing concrete, the resulting concrete composition undergoes little change in the slump for a lengthened time, so that the quality of the concrete composition can be easily controlled.