| 摘要 |
1360452 Coating compositions containing hydrolysed organotrihydrocarbonoxysilanes STAUFFER CHEMICAL CO 24 Sept 1971 [25 Sept 1970] 42263/73 Divided out of 1360451 Heading C3T A coating composition comprises particulate solids and a binder composition obtained by reaction of a silane in which R and R<SP>1</SP> are C 1-10 hydrocarbon radicals, R<SP>11</SP> is a divalent C 2-6 hydrocarbon radical and R<SP>111</SP> is H or a C 1-10 hydrocarbon radical with at least 0À8 moles of water per Sibonded hydrocarbonoxy group in the presence of sufficient acid (other than an organic acid free of hydroxy groups) to provide a pH of 1À0- 5À5, the binder : solids ratio being 70-10 : 30- 90 by weight. Preferably the binder contains 5-40 wt. per cent of SiO 2 . The hydrolysis is preferably conducted in an organic solvent, e.g. a higher-boiling ether, alcohol, glycol, ketone, hydrocarbon or halohydrocarbon. The preferred solids are zinc dust, which may be mixed with Ca or Mg metasilicate or a fibrous mineral filler or a pigment, e.g. Fe 2 O 3 , CdS, TiO 2 or a lithopone. In Examples 1-22, water is added, in proportions of 0À5-2À5 moles per mole of Sibound alkoxy group (Examples 1-3 being comparative), to a solution of MeSi(OEt) 3 , BuSi(OBu) 3 , PhSi(OEt) 3 , MeSi(OPh) 3 , MeSi- (OC 8 H 17 ) 3 , or MeSi(OC 2 H 4 OMe) 3 in ethoxyethanol, methoxyethanol or ethanol in the presence of HCl; further solvent is optionally added and the product mixed with Zn dust. In Examples 23 and 24 one of the above binders is mixed with Zn dust and CaMgAl silicate or with a mixture of talc and Fe 2 O 3 . |
