UV-scattering inorganic/polymer composite particles and a method for preparing the same
AssigneeAmorepacific Corporation
InventorsJin Woong Kim, Jong Won Shim, Young Ha Lee, Han Kon Kim, Hak Hee Kang
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Abstract
There are provided inorganic/polymer composite particles having good UV-scattering efficiency and improved dispersion stability in organic formulation; and a method for preparing the same, which comprises the following steps of (1) dispersing hydrophobic-treated inorganic particles in monomer and then adding initiator thereto; (2) emulsifying the inorganic dispersion of step (1) in presence of surfactant and dispersion stabilizer; and (3) suspension polymerizing the inorganic/monomer emulsion of step (2), to give inorganic/polymer composite particles.
Claims14
A composite particle comprising a polymer particle and inorganic particles entrapped in said polymer particle, wherein said inorganic particles are titanium dioxide, zinc oxide or a mixture thereof and dispersed within said polymer particle, wherein said composite particle is obtained by suspension polymerization of an emulsion comprising a monomer and said inorganic particles, wherein said inorganic particles are surface-treated with an organic material prior to being mixed with the monomer for suspension polymerization,
- wherein said inorganic particles are primarily surface-treated with at least one organic materials selected from saturated or unsaturated fatty acids having 5-30 carbon atoms, and
- wherein said primarily surface-treated inorganic particles are secondarily surface-treated with a dimethicone chain.
A method for preparing a composite particle comprising a polymer particle and inorganic particles entrapped in said polymer particle, said inorganic particles being dispersed within said polymer particle, which method comprises the following steps of
- (1) dispersing pre-surface-treated inorganic particles in a monomer and then adding an initiator thereto to give a dispersion, wherein said inorganic particles are titanium dioxides, zinc oxides or a mixture thereof;
- (2) emulsifying the dispersion of step (1) in the presence of a dispersion stabilizer;
- and
- (3) suspension polymerizing the resulting emulsion of step (2), to give the composite particles,
- wherein said inorganic particles in step (1) are primarily surface-treated with at least one organic materials selected from saturated or unsaturated fatty acids having 5-30 carbon atoms, and
- wherein said primarily surface-treated inorganic particles are secondarily surface-treated with a dimethicone chain.
A UV-blocking cosmetic composition containing composite particles in an amount of 0.1-10% by weight based on the total weight of the composition, said composite particles having a structure that inorganic particles are dispersed within an individual polymer particle and being prepared by a method comprising the steps of:
- (1) dispersing inorganic particles in a monomer and then adding an initiator thereto to give a dispersion, wherein said inorganic particles are titanium dioxides, zinc oxides or a mixture thereof;
- (2) emulsifying the dispersion of step (1) in the presence of a dispersion stabilizer;
- and
- (3) suspension polymerizing the resulting emulsion of step (2), to give the composite particles,
- wherein said inorganic particles in step (1) are, prior to being dispersed in the monomer, primarily surface-treated with at least one organic materials selected from saturated or unsaturated fatty acids having 5-30 carbon atoms, and
- wherein said primarily surface-treated inorganic particles are, prior to being dispersed in the monomer, secondarily surface-treated with a dimethicone chain.
Dependencies are inferred from the claim text.