Glass fibers coated with compositions containing complex organo silicon compounds

Claim 1

Glass fibers having a thin size coating thereon, said coating comprising an organo silane having the formula ##EQU36## wherein R is hydrogen or methyl, x is an integer from 3 to 6, and R 1 is alkyl or hydrolysis products thereof, and an organo silicon compound prepared by reaction of (1) a halosilane selected from the group consisting of a tetrahalosilane and a halosilane of the formula (R.sub.7).sub.n SiX.sub.4.sub.-n wherein R 7 is an organic group containing 1 to 20 carbon atoms, n is an integer from 1 to 2 and X is halogen, (2) a monoepoxide selected from the group consisting of an alkylene oxide, a functional epoxide having the formula ##EQU37## wherein R 2 is selected from the group consisting of aryl, alkyl, alkenyl and a group having the formula ##EQU38## where R' is hydrogen or methyl, and combinations thereof, and (3) a diepoxide selected from the group consisting of an epoxide of the formula ##EQU39## wherein R 3 is a divalent organic group and a cycloalkane diepoxide, with (2) being reacted in a ratio of 1 to 3 epoxide equivalents per mole of (1) and (3) being reacted in a ratio of 0.5 to 3 epoxide equivalents per mole of (1).