Patent ID: 6811723
Filing Date: 2004-11-02
Classification: A61K,A61Q,B82Y,C01G,C01P,C08K,C09C,C09D

Abstract:
Process for the preparation of an organic sol, comprising:titanium oxide particles; an organic liquid phase; at least one amphiphilic compound having a formulae: wherein,R1, R2, and R3 are a linear or branched alkyl group, a phenyl group, an alkylaryl group or an arylalkyl group; n represents the number of ethylene oxide units and wherein n is from two to twelve; and M1 represents a hydrogen, sodium or potassium atom, the process comprising the following steps: a) preparing, as starting product, titanium dioxide particles by hydrolysis of at least one titanium compound A in the presence of at least one compound B selected from the group consisting of: (i) acids which have: either a carboxyl group and at least two hydroxyl and/or amine groups, or at least two carboxyl groups and at least one hydroxyl and/or amine group, (ii) organic phosphoric acids of the following formulas: in which n1 and m are integers between 1 and 6, p is an integer between 0 and 5, R4, R5 and R6 identical or different represent a hydroxyl, amino, aralkyl, aryl, alkyl group or hydrogen group,(iii) compounds capable of releasing sulphate ions in an acid medium, (iv) salts of the acids described above and in the presence of anatase titanium dioxide seeds; b) optionally at least partially covering the particles by a layer of at least one of a silicon oxide, hydroxide or oxyhydroxide or a metallic oxide, hydroxide or oxyhydroxide; and c) mixing the amphiphilic compound and the organic liquid phase together, then dispersing the titanium oxide particles in the mixture obtained, or forming a mixture of titanium oxide particles and at least one of the aforementioned amphiphilic compounds, then dispersing said mixture in the liquid phase.