Synthetic organic particles, process for the production of the same, and use thereof
AssigneeMatsumoto Yushi-Seiyaku Co., Ltd.
InventorsMitsutoshi Nishida, Ichiro Takahara
Life of this patent
Estimating the term…
Abstract
Synthetic organic particles each constituted of a core made from an organic polymer and a surface layer formed from a methacrylate resin on the surface of the core. In one of the particles, the core is made from a copolymer comprising 80 to 99 weight percent of a lower alkyl acrylate and 1 to 20 weight percent of a polyfunctional vinyl monomer to exhibit rubberlike elasticity, while in another of the particles, the core is made from a copolymer of a reactive benzotriazol compound and a (meth)acrylic monomer to exhibit an ultraviolet absorbing activity. These synthetic organic particles can be suitably added to cosmetics to impart a feeling of creamy softness and an ultraviolet screening power to them.
Claims29
Synthetic organic particles having an average particle size of 1.02 to 18 μm, and comprising:
- (A) cores of an organic polymer, the said organic polymer comprising a copolymer of 80 to 99 weight percent of lower alkyl acrylate and 1 to 20 weight percent of polyfunctional vinyl monomer, said copolymer having rubbery elasticity;
- and
- (B) a surface layer of a methacrylate resin being formed on the surface of the said cores;
- and having
- (C) rubbery elasticity.
A process for producing synthetic organic particles comprising:
- (1) suspension polymerizing 80 to 99 weight percent of lower alkyl acrylate and 1 to 20 weight percent of polyfunctional vinyl monomer in an aqueous medium to form core particles of an organic polymer having rubbery elasticity;
- and
- (2) adding lower alkyl methacrylate or a combination of lower alkyl methacrylate and polyfunctional vinyl monomer in the polymerization system containing the said core particles, and polymerizing the added monomer(s) on the surface of the said core particles to form a surface layer of methacrylate resin on the surface of the said core particles.
Synthetic organic particles having an average particle size of 1.02 to 18 μm, and comprising:
- (A′) cores of organic polymer, said polymer being a copolymer of a reactive benzotriazol compound and (meth)acrylic monomer, and having ultraviolet-ray absorbing function;
- and
- (B′) a surface layer of a methacrylate resin and formed on the surface of said cores;
- said particles having
- (C′) ultraviolet-ray absorbing function.
A process for producing synthetic organic particles comprising:
- (1) dispersing a reactive benzotriazol compound, (meth)acrylic monomer and toluene in an aqueous medium, and polymerizing them to form polymer particles, in which toluene is encapsulated,
- (2) adding lower alkyl methacrylate or a combination of lower alkyl methacrylate and polyfunctional vinyl monomer in the polymerization system containing the said polymer particles and polymerizing the added monomers on the surface of the said polymer particles to form a surface layer of methacrylate resin on the said polymer particles, and
- (3) separating the polymer particles having the surface layer produced in step (2) and drying the particles to evaporate and remove the encapsulated toluene from the polymer particles.
A process for producing synthetic organic particles comprising:
- (1) polymerizing 80 to 99 weight percent of lower alkyl acrylate and 1 to 20 weight percent of polyfunctional vinyl monomer in an aqueous medium to form core particles of organic polymer having rubbery elasticity, said core particles having an average particle diameter of from 1 to 16 μm;
- and
- (2) adding lower alkyl methacrylate or a combination of lower alkyl methacrylate and polyfunctional vinyl monomer in the polymerization system containing said core particles, and polymerizing the added monomer(s) on the surface of said core particles to form a surface layer of methacrylate resin on the surface of said core particles, and wherein the average size of the resulting particles comprising the core particles and surface layer is from 1.02 to 18 μm.
Dependencies are inferred from the claim text.