Patent ID: 6841599

Claim:
A process for producing a solid, water-soluble or water-dispersible composition comprising a non film-forming material supported by a film-forming polymer wherein the supported material is a water-soluble material, which process comprises (i) preparing a film-forming aqueous medium containing (a) a film-forming polymer which is a partially or fully charged homopolymer or a partially charged block copolymer or a homopolymer or block copolymer capable of ring-opening to form a partially charged homopolymer or block copolymer and (b) a water soluble material which is non film-forming and thereafter (ii) drying the film-forming aqueous medium to form the solid composition, wherein the film-forming aqueous medium is prepared using water as the sole medium for both the film-forming polymer (a) and the water-soluble material (b) and wherein the film-forming polymer is selected from the group consisting of an alkyl vinylether maleic anhydride block co-polymer, a hydrolysed alkyl vinylether maleic anhydride block co-polymer, a salt of poly (acrylic acid/maleic acid) copolymer, a salt of sulphonated poly (styrene/maleic anhydride) copolymer, a salt of sulphonated polystyrene and a salt of sulphonated polyvinyl alcohol.