| 摘要 |
<p>1502803 Silicon polymer coatings DOW CORNING CORP 17 March 1975 [25 June 1974] 10991/75 Heading B2E [Also in Division C3] A paint which may be applied to phosphated or stainless steel, cement, tiles or polyurethane insulators comprises a pigment and a vehicle of pH 3-6 which is a dispersion of colloidal silica in a solution in water/ of a partial condensate of a silane triol RSi(OH) 3 , the silica and condensate amounting to 10-60 wt. % of the vehicle and being in a 10:90 to 70:30 wt. ratio, and at least 70 wt. % of the silane triol being CH 3 Si(OH) 3 , any other groups R being C 2 H 5 - C 3 H 7 -, CH 2 = CH -, CF 3 CH 2 CH 2 -, or gamma-glycidoxy- or -methacryloxy-propyl radicals. The silanol may be formed in situ by adding a trialkoxysilane to a silica hydrosol, which is then acidified. Preferably 1-200 pbw of pigment is added to 100 pbw of vehicle, and the paint should be used within 24 hrs. In Examples vehicles are obtained by adding CH 3 Si(OCH 3 ) 3 to a colloidal silica acidified with acetic acid; paints are obtained by adding thereto TiO 2 , alone or with mica and zinc or with a china clay, or black iron oxide.</p> |
