Method and materials for producing a printing master
US5212030A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Nov 21, 1989 |
| Grant date | May 18, 1993 |
| Priority date | — |
| Expiry date | Nov 21, 2009 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G13/283
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A specially coated paper which has been prepared for imaging in an electrophotographic reproduction process, and a method for developing an image produced on this paper so that it may be used as a lithographic printing plate. The base material is polyester and is coated with either a thermoplastic or cross-linking resin or mixture of resins. The layer which is used for coating the polyester is loaded with zinc oxide. Once the printing plate has been prepared, it is then imaged in a photocopier or laser printer using the indirect electrophotographic process. Background dots can then be eliminated by application of a specific mixture to the printing plate before printing. The mixture preferably consists of an emulsion with an external hydrophilic phase, and an internal lipophylic/solvent phase held together by a surfactant or mixture of surfactants. Optionally, the external phase may also contain an aqueous solution of ferrocyanide or tannic acid or any other known conversion agent so that it may be applied to the plate without the need for previously etching it with the conventional electrostatic conversion etch. The plates may be imaged in laser printers, so that printing plates ma…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.