Patent · US Expired

Method for making positive working printing plates from a heat mode sensitive image element

US6251563A · kind A · utility

10Cited by
4References
8Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1998
Grant dateJun 26, 2001
Priority date
Expiry dateSep 30, 2018

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S430/145
  • WIPO fieldTextile and paper machines
  • WIPO sectorMechanical engineering

Abstract

According to the present invention there is provided a method for making lithographic printing plates including the following steps PA1 a) preparing a heat mode imaging element consisting of a lithographic base with a hydrophilic surface and a top layer which top layer is sensitive to IR-radiation, comprises a polymer, soluble in an aqueous alkaline solution and is unpenetrable for an alkaline developer containing SiO.sub.2 as silicates; PA1 b) exposing imagewise said heat mode imaging element to IR-radiation; PA1 c) developing said imagewise exposed heat mode imaging element with said alkaline developer so that the exposed areas of the top layer are dissolved and the unexposed areas of the top layer remain undissolved characterized in that said top layer includes an IR-absorbing pigment and 3,4,5-trimethoxybenzoic acid or a benzophenone.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.