| 摘要 |
1397518 Etching NCR CORP 9 May 1973 [15 May 1972] 22092/73 Addition to 1275686 Heading B6J A cast body of at least two polymeric materials which materials may exist as a homogeneous, substantially transparent solid solution or as a heterogeneous translucent solid is imaged by applying a stimulus to cause the materials in selected areas of the body to change from the solid solution to the heterogeneous translucent solid condition and the imaged areas are etched by applying thereto a solvent for at least one of the polymeric materials in the imaged areas which solvent will not dissolve the polymeric materials in the remaining areas. The polymeric materials and the methods by which they are imaged are disclosed in the parent Specification 1,275,686 (Division B5). The etching agent may be water, methanol, ethanol or mixtures thereof. A dye may be added to the etching liquid such that the etched block may be used as a printing plate by transference of the dye to a copy sheet. |
