Abstract: An aqueous microcapsule suspension liquid exhibiting an excellent (long-term) storage stability and allowing easy re-dispersion and dilution with water even after such a storage, is produced by adding a microorganism-fermented polysaccharide of succinoglycan type as a thickening agent into a microcapsule slurry, or by adding such a microorganism-fermented polysaccharide as a thickening agent to a microcapsule slurry after uniform dilution with water.

Abstract: An aqueous microcapsule suspension liquid exhibiting an excellent (long-term) storage stability and allowing easy re-dispersion and dilution with water even after such a storage, is produced by adding a microorganism-fermented polysaccharide of succinoglycan type as a thickening agent into a microcapsule slurry, or by adding such a microorganism- fermented polysaccharide as a thickening agent to a microcapsule slurry after uniform dilution with water.

Abstract: In an image-forming medium, a sheet of paper is coated with a layer of microcapsules which is composed of a binder material and a plurality of microcapsules filled with dye and uniformly distributed in the binder material. The binder material exhibits a predetermined thermal melting point, and the microcapsules exhibit a pressure-breaking characteristic so as to be squashed and broken under a predetermined pressure when said binder material is thermally softened or melted. When a leuco-pigment-based dye is used, a color developer is substituted for the binder material.

Abstract: A first heat-sensitive microcapsule of the present invention comprises a shell wall and a liquid coloring composition, and has such a temperature-breaking characteristic that the shell wall is broken by heating to a temperature equal to or higher than a boiling point of the liquid coloring composition. The first heat-sensitive microcapsule is stable to light and easy to handle. A second heat-sensitive microcapsule of the present invention comprises a shell wall, a coloring composition and a heat decomposition-type gas-developing agent, and has such a temperature-breaking characteristic that the shell wall is broken by heating to a temperature equal to or higher than a decomposition temperature of the gas-developing agent. The second heat-sensitive microcapsule can be sensitively broken even by heating in a short time.

Abstract: A microcapsule (or microencapsulated product) having a uniform and smooth coating film and also an excellent performance of gradually liberating the content material is produced at a good particle size distribution while suppressing the occurrence of isolated or aggregated film material, aggregated microcapsules and isolated core material. The production process includes: a first coating step of mixing a water-soluble cationic amino resin and an anionic surfactant in the presence of a hydrophobic core material dispersed in an aqueous medium to coat the dispersed core material with a coacervate of the cationic amino resin and the anionic surfactant; and a second coating step of adding an amino resin prepolymer into an aqueous dispersion liquid containing the coated dispersed core material and polycondensating the amino resin prepolymer to further coat the coated dispersed core material with a polycondensate of the amino resin prepolymer.

Abstract: A first heat-sensitive microcapsule of the present invention comprises a shell wall and a liquid coloring composition, and has such a temperature-breaking characteristic that the shell wall is broken by heating to a temperature equal to or higher than a boiling point of the liquid coloring composition. The first heat-sensitive microcapsule is stable to light and easy to handle. A second heat-sensitive microcapsule of the present invention comprises a shell wall, a coloring composition and a heat decomposition-type gas-developing agent, and has such a temperature-breaking characteristic that the shell wall is broken by heating to a temperature equal to or higher than a decomposition temperature of the gas-developing agent. The second heat-sensitive microcapsule can be sensitively broken even by heating in a short time.

Abstract: A microcapsule (or microencapsulated product) having a uniform and smooth coating film and also an excellent performance of gradually liberating the content material is produced at a good particle size distribution while suppressing the occurrence of isolated or aggregated film material, aggregated microcapsules and isolated core material. The production process includes: a first coating step of mixing a water-soluble cationic amino resin and an anionic surfactant in the presence of a hydrophobic core material dispersed in an aqueous medium to coat the dispersed core material with a coacervate of the cationic amino resin and the anionic surfactant; and a second coating step of adding an amino resin prepolymer into an aqueous dispersion liquid containing the coated dispersed core material and polycondensating the amino resin prepolymer to further coat the coated dispersed core material with a polycondensate of the amino resin prepolymer.

Abstract: In an image-forming medium, a sheet of paper is coated with a layer of microcapsules which is composed of a binder material and a plurality of microcapsules filled with dye and uniformly distributed in the binder material. The binder material exhibits a predetermined thermal melting point, and the microcapsules exhibit a pressure-breaking characteristic so as to be squashed and broken under a predetermined pressure when said binder material is thermally softened or melted. When a leuco-pigment-based dye is used, a color developer is substituted for the binder material.

Abstract: Disclosed herein is a partially pressure-sensitive recording paper on which an ink has been applied partially, the ink having been prepared by uniformly dispersing microcapsules having a solution of a colorless electron-donating dyestuff as the core material, a thermally melting solid substance and an organic solvent having a mean boiling point of from 250.degree. to 350.degree. C. and a content of aromatic ring carbon of more than 25% while restraining the weight ratio of the solvent to the solid substance and the weight ratio of the solid substance to the microcapsules respectively in a prescribed range.