摘要 |
<p>1397580 Coated glass fabric and fibres EI DU PONT DE NEMOURS & CO 24 May 1972 [25 May 1971 15 May 1972] 52472/74 Heading B2E [Also in Division C3] A composite structure comprising a glass fabric and a coating thereon comprising a base coat of a condensation product of a polyhydrolysable silane and a top coat of an unsintered, fine powder polytetrafluoroethylene having an apparent melt viscosity of at least 1 x 10<SP>9</SP> poises at 380‹C, the coating weight being from 1 to 80 grams per square metre of glass fabric surface area may be prepared by forming a base coating of a condensation product of the polyhydrolysable silane on a glass yarn or fabric and then forming a top coat thereon of the polytetrafluoroethylene by coating the yarn or fabric with an aqueous dispersion of the polytetrafluoroethylene and heating the top coat to dry it at a temperature insufficient to cause sintering of the polytetrafluoroethylene and in the case of a coated glass yarn forming it into a fabric. The polyhydrolysable silane is a compound containing at least one Si-C (aliphatic carbon atom) group and having the capability to undergo first hydrolysis, to render it condensible, and then condensation.</p> |