| 摘要 |
<p>1463509 Coated photographic carrier material FELIX SCHOELLER JR KG 21 Feb 1974 [22 Feb 1973] 8057/74 Heading B2E A polyolefine coated photographic carrier material, e.g. paper extrusion coated with polyethylene, has a crystalline coating of CaF 2 , MgF 2 , ZnF 2 and/or PbF 2 which coating incorporates silicic acid and a matting agent. The matting agent is based on calcium silicate or calcium carbonate and includes a fraction in which calcium or magnesium is present in the form of an oxide, hydroxide or other alkaline compound of calcium or magnesium. The coating may also contain as anti-static agent, e.g. an alkali or ammonium salt of a polycarboxylic acid, e.g. polyacrylic or polymethacrylic acid, or a polysulphoric acid. Suitable agents include polyacrylic acid propyl ester having 5% polymerised vinyl ether, polyacrylic acid propyl or butyl ester or a styrene butadiene interpolymer with a butadiene content of over 50%. The polyolefine surface may be activated by corona discharge before coating. The coating may be applied as an aqueous solution or dispersion containing a water-soluble calcium, magnesium, zinc and/or lead salt of hexafluorosilicic acid and a matting agent based on calcium silicate or calcium carbonate including a fraction in which calcium or magnesium is present as an alkaline compound. A portion of the calcium may be replaced by aluminium or magnesium.</p> |
