To provide a re-dispersible emulsion powder that can suitably used in already formulated cement admixture, a powdery coating, a powdery adhesive and the like, particularly shows excellent miscibility, re-dispersibility and workability with inorganic fillers and polyvalent inorganic salts or the like to be used in the civil engineering and/or for building materials and is suitable as an admixture for extra quick hardening cement.
The objective re-dispersible emulsion powder comprises vinyl copolymer particles that have an anionically modified polyvinyl alcohol adsorbed on their surfaces. In a preferred embodiment, the vinyl monomer composition is emulsion-polymerized in an aqueous medium in the presence of an anionically modified polyvinyl alcohol. In another preferred embodiment the anionically modified polyvinyl alcohol is at least one selected from a sulfonic acid-modified polyvinyl alcohol and from a carboxylic acid-modified polyvinyl alcohol.
KATSUKI MASAMI
UEHORI SOUICHI
OKAYASU KATSUYUKI
IGARASHI ARATA
