Patent · US Expired

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

US6004728A · kind A · utility

31Cited by
3References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 30, 1998
Grant dateDec 21, 1999
Priority date
Expiry dateSep 30, 2018

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB41M5/465
  • 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 having on a lithographic base with a hydrophilic surface a first layer including a polymer, soluble in an aqueous alkaline solution and a top layer on the same side of the lithographic base as the first layer which top layer is sensitive to IR-radiation and is unpenetrable for an alkaline developer containing SiO.sub.2 as silicate; 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 and the underlying areas of the first layer are dissolved and the unexposed areas of the first layer remain undissolved characterized in that said top layer includes an IR-dye.

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