摘要 |
PCT No. PCT/GB91/00180 Sec. 371 Date Sep. 30, 1992 Sec. 102(e) Date Sep. 30, 1992 PCT Filed Feb. 6, 1991 PCT Pub. No. WO91/42140 PCT Pub. Date Aug. 22, 1991.A lithographic plate comprising a substrate carrying an oxide layer derived from a Type A sol is disclosed. The substrate may be metal, e.g. aluminum or steel, and may be in a mill finished state or grained or otherwise profiled. Type A sols have polynuclear cations but no specific particles and may be formed by peptising basic salts with acids. The sol may include an inorganic passenger powder which may impart a desired topography to the coating layer. |