A method of preparing sunscreens in which a dispersion of zinc oxide particles in an oil is formed by milling in the presence of a particulate grinding medium and mixed with cosmetically acceptable materials is claimed. The particles of zinc oxide have an average size of from 0.005 to 0.15 micron and the dispersion is substantially transparent to visible light but with an extinction coefficient at 308 nm (E(308)) and at 360 nm (E(360)) of at least 9 liters per gram per centimeter. The ratio E(360):E(308) is in the range 0.75:1 to 1.5:1. In a preferred method a mixed dispersion containing titanium dioxide and zinc oxide, having E(308) at least 15 liters per gram per centimeter, E(360) at least 10 liters per gram per centimeter and the ratio E(360):E(308) in the range 0.3:1 to 1.5:1 is used. The mixed dispersion is also claimed. The sunscreens prepared have a good balance of absorption for UVA and UVB radiation and better SPF values than those prepared from titanium dioxide and/or zinc oxide powders.

Method of preparing sunscreens

An aqueous dispersion of acicular fine particle size titanium dioxide containing from 20 to 60% by weight solids content and a polycarboxylic dispersant is of outstanding use in the preparation of sun screens. The dispersions are transparent to visible light and absorbant to UV light of broad spectrum. Usually the titanium dioxide has a largest dimension within the range 0.01 to 0.15 micron. The dispersions are produced by milling, preferably in a high speed mill, until the required UV absorbancy is attained.

Aqueous dispersions of acicular titanium dioxide

A titanium dioxide- or iron oxide-coated mica pearlescent pigment having a coating which contains a combination of hydrated cerium and aluminum oxides has enhanced weatherstability.

Weather Resistant Pearlescent Pigments

A predetermined amount of an aluminum compound and/or a zinc compound is added to a hydrous titanium dioxide prepared by hydrolysis of titanium sulfate, and the mixture is fired to introduce a suitable amount of aluminum and/or zinc into the crystal to compensate for the crystal defect of anatase titanium dioxide and to enhance the stability, thereby realizing an excellent color stability.

Stable anatase titanium dioxide and process for preparing the same

The present invention provides a pigmentary titanium composite having good durability and excellent optical properties. The inventive composite consists essentially of: a particulate titanium dioxide base; a hydrous zirconium oxide layer deposited on the titanium dioxide base ; and a hydrous alumina layer deposited on the hydrous zirconium oxide layer. The alumina layer consists essentially of boehmite alumina and/or pseudoboehmite alumina. The present invention also provides a method for preparing the inventive pigmentary composite. The inventive method comprises the steps of: (a) preparing an aqueous slurry comprising water and a particulate titanium dioxide base ; (b) depositing a layer of a hydrous zirconium oxide precipitate on the titanium dioxide base ; and (c) depositing a layer of a hydrous alumina precipitate on the layer of hydrous zirconium oxide. The hydrous alumina precipitate consists essentially of boehmite alumina and/or pseudoboehmite alumina.

Titanium dioxide pigment and method of preparation

This invention provides a titanium dioxide pigment improved in durability and dispersibility which a comprises pigmentary titanium dioxide core particle, an inner coating of hydrous oxides of tin and zirconium and an outer coating of hydrous oxide of aluminum, and a process for producing said titanium dioxide pigment.

Titanium dioxide pigment and process for producing same

PURPOSE: To obtain a stable quality of fine titanium dioxide composition powder at low cost by a procedure in which aluminium hydroxide is deposited on the surfaces of noncoagulative titanic acid or titanium dioxide in an aqueous slurry, before or after which the titanic acid or titanium dioxide is baked. CONSTITUTION: In the process (A), an acid aqueous solution of titanium is hydrolyzed to obtain noncoagulative titanic acid, and then in the process (B), the noncoagulative titanic acid or titanium dioxide obtained therefrom is dispersed into water to obtain an aqueous slurry. Then, 0W10wt% (in terms of SiO 2 on the basis of TiO 2 ) a silicone hydroxide and 1W10wt% (in terms of Al 2 O 3 on the basis of TiO 2 ) an aluminium hydroxide are deposited on the surfaces of noncoagulative titanic acid or titanium dioxide particles in the aqueous slurry. In the process (C), before or after the deposition process (B), the noncoagulative titanic acid or titanium dioxide is baked at 700°C or more so that 80% or more of the noncoagulative titanic acid become fine titanium oxide powder of a grain size of 0.02W0.07microns. COPYRIGHT: (C)1980,JPO&Japio

Manufacture of fine titanium dioxide composition powder

PURPOSE:To obtain a titanium dioxide pigment having excellent whiteness and light resistance, by coating titanium dioxide particles with specified amounts of hydrated antimony oxide and then an alumina/silica coprecipitate in turn, and calcining the resulting particles CONSTITUTION:A water-soluble antimong compd is added to an aq slurry of titanium dioxide The resulting slurry is neutralized to coat the titanium dioxide particles with less than 1% (in terms of Sb2O3 based on the weight of titanium dioxide) hydrated antimony oxide Then there are added a water-soluble aluminum compd and a water-soluble silicon compd The resulting mixture is neutralized to coated the titanium dioxide particles with an alumina/silica coprecipitate in an amount of 2-6% (in terms of Al2O3) alumina and 2-6(in terms of SiO2) silica, each based on the weight of titanium dioxide The resulting coated titanium dioxide is recovered from the aq slurry, and calcined at 400-800lto obtain the desired titanim dioxide pigment

Mamoru Matsunaga

Papers

Titanium dioxide pigment and process for producing same

Manufacture of fine titanium dioxide composition powder

Production of titanium dioxide pigment

Titandioxidpigment und Verfahren zu seiner Herstellung

Titanium dioxide pigment and process for its manufacture