| 摘要 |
1472431 Reflectors MINNESOTA MINING & MFG CO 11 April 1974 [16 April 1973] 16389/74 Heading B2E [Also in Division C1] Reflective signs are made by applying to a substrate, transparent microspheres of 1-200 microns diameter containing more than 50% anatase TiO 2 and optionally oxides of Fe, Al, Cr, Co and Si (see Division Cl). In Example 7, polyester sheet is coated with a tacky vinylidene fluoride-perfluoroproprene fluorinated elastomer in which a layer of microspheres is embedded and then the exposed surfaces are vapour plated with Al. In Example 8, polyacrylate treated paper is coated twice with an alkyd resin, a monolayer of microspheres, a coating of polyvinyl butyral and then vapour deposited Al. The assembly may then be stripped from the paper. In Example 9, polyacrylate treated paper is coated with a blend of nitrile rubber, phenolic resin and Al powder and the microspheres are embedded therein. |
