초록 ▼

A process is disclosed for performing encapsulation, en masse, by an in situ polymerization reaction to yield capsule wall material. The reaction comprises the polymerization of urea and formaldehyde, or monomeric or low molecular weight polymers of dimethylol urea or methylated dimethylol urea, mel

A process is disclosed for performing encapsulation, en masse, by an in situ polymerization reaction to yield capsule wall material. The reaction comprises the polymerization of urea and formaldehyde, or monomeric or low molecular weight polymers of dimethylol urea or methylated dimethylol urea, melamine and formaldehyde, monomeric or low molecular weight polymers of methylol melamine or methylated melamine, in an aqueous vehicle and the reaction is conducted in the presence of certain acrylic acid copolymers. The disclosed encapsulation process provides improved resistance of the emulsion of intended capsule core material to destabilization and permits the manufacture of microcapsules with improved drop size distribution, improved resistance to frictional smudge damage and enhanced impermeability.

대표청구항 ▼

A process for preparing microcapsules in an aqueous manufacturing vehicle which comprises enwrapping particles of intended capsule core material, substantially insoluble in said vehicle, with polymeric shells produced by in situ polymerization of melamine and formaldehyde, methylol melamine, methyla

A process for preparing microcapsules in an aqueous manufacturing vehicle which comprises enwrapping particles of intended capsule core material, substantially insoluble in said vehicle, with polymeric shells produced by in situ polymerization of melamine and formaldehyde, methylol melamine, methylated methylol melamine, urea and formaldehyde, dimethylol urea or methylated dimethylol urea in the presence of an acrylic acid-alkyl methacrylate copolymer, wherein the weight percent and type of alkyl methacrylate in said copolymer is selected from the group consisting of about 1 to about 20 propyl methacrylate, about 0.5 to about 20 butyl methacrylate, about 0.5 to about 15 amyl methacrylate, about 0.5 to about 10 hexyl methacrylate and about 0.5 to about 10 cyclohexyl methacrylate and said copolymer is present as about 0.4 to about 15 percent by weight of said manufacturing vehicle. Microcapsules produced by a process as claimed in claim 1.