Abstract: The invention provides a thermally foamable microsphere having a structure with a foaming agent encapsulated in a shell formed of a polymer, wherein the shell contains an organosilicon compound, and a process for producing a thermally foamable microsphere having a structure with a foaming agent encapsulated in a shell formed of a polymer by suspension polymerization of a polymerizable mixture containing at least a foaming agent and a polymerizable monomer in an aqueous dispersion medium, wherein the polymerizable mixture is suspension polymerized in the presence of the organosilicon compound.

Abstract: The invention provides a thermally foamable microsphere whose shell is formed of a polymer that is obtained by the polymerization of a polymerizable monomer and a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer and which has a maximum expansion ratio of at least 5. The invention also provides a process for the production of a thermally foamable microsphere having a maximum expansion ratio of at least 5 by the suspension polymerization of a polymerizable mixture containing a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer.

Abstract: The invention provides a thermally foamable micro-sphere whose shell is formed of a polymer that is obtained by the polymerization of a polymerizable monomer and a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer and which has a maximum expansion ratio of at least 5. The invention also provides a process for the production of a thermally foamable microsphere having a maximum expansion ratio of at least 5 by the suspension polymerization of a polymerizable mixture containing a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer.

Abstract: The invention provides a thermally foamable microsphere having a structure with a foaming agent encapsulated in a shell formed of a polymer, wherein the shell contains an organosilicon compound, and a process for producing a thermally foamable microsphere having a structure with a foaming agent encapsulated in a shell formed of a polymer by suspension polymerization of a polymerizable mixture containing at least a foaming agent and a polymerizable monomer in an aqueous dispersion medium, wherein the polymerizable mixture is suspension polymerized in the presence of the organosilicon compound.

Abstract: Foamable microspheres with a foaming agent enclosed in the shell of a polymer, wherein the average particle diameter of the microspheres is within a range of 3 to 100 &mgr;m, and the coefficient of variation of the particle diameter distribution thereof is at most 1.50%, and production process of foamable microspheres by a suspension polymerization process.

Abstract: The invention provides a thermally foamable micro-sphere whose shell is formed of a polymer that is obtained by the polymerization of a polymerizable monomer and a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer and which has a maximum expansion ratio of at least 5. The invention also provides a process for the production of a thermally foamable microsphere having a maximum expansion ratio of at least 5 by the suspension polymerization of a polymerizable mixture containing a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer.

Abstract: The invention provides a thermally foamable microsphere whose shell is formed of a polymer that is obtained by the polymerization of a polymerizable monomer and a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer and which has a maximum expansion ratio of at least 5. The invention also provides a process for the production of a thermally foamable microsphere having a maximum expansion ratio of at least 5 by the suspension polymerization of a polymerizable mixture containing a crosslinkable monomer at a proportion of greater than 1% by weight up to 5% by weight based on the polymerizable monomer.

Abstract: A suspension of a particulate porous fluorinated resin in an aqueous medium containing a powder of an inorganic suspension stabilizer is heated approximately at a melting temperature of the resin whereby the resin is densified, the degree of densification of the resin depending on the heating temperature.