摘要 |
<p>A sheet of polyvinyl butyral, used as an inter-layer in safety glass (see Group VIII), is plasticized with up to 2,5% of its weight of a silicic acid ester of an aliphatic alcohol having 3 to 6 carbon atoms in the molecule, or of a monoether of ethylene glycol, e.g. butyl silicate or the silicate of the monobutyl ether of ethylene glycol. The sheet may also contain a conventional plasticizer, e.g. triethyleneglycol diethyl acetate. Specification 755,809 is referred to.</p> |