| 摘要 |
<p>A printing plate useful in lithographic printing is prepared by the process comprising: (a) applying an alkali soluble composition comprising at least one polymer composition to a hydrophilic surface on a substrate to provide the surface face with at least one layer which is alkali soluble at a pH in the range of about 6.0 to 14.0; (b) imaging the coated substrate electrostatically with a toner composition; (c) heating the imaged substrate a first time to a temperature greater than the glass transition temperature of the toner composition; (d) contacting the imaged substrate with an aqueous alkaline solution havign a pH in the range of about 6.0 to about 14.0; and (e) heating the imaged substrate a second time to a temperature greater than the glass transition temperature of the toner composition. This printing plate is capable of long runs on press with good image quality and advantageously minimizes the occurrence of undesirable background toner 'specking' on press. Accordingly, the printing plate is satisfactory for demanding printing tasks such as four-color newspaper printing, financial printing and the like.</p> |
