Presensitized lithographic printing plate and method for preparing lithographic printing plate
US5858604A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jan 16, 1996 |
| Grant date | Jan 12, 1999 |
| Priority date | — |
| Expiry date | Jan 16, 2016 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S430/145
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Object: A method for preparing a lithographic printing plate directly from digital image signals with the use of a presensitized lithographic printing plate comprising a support having thereon a photosensitive layer and a light-shielding layer which can be removed imagewise with laser light is provided, wherein the light-shielding layer, which can be industrially produced readily at a moderate price can be removed sufficiently during a process of development without the need of removing a masking layer at an unexposed portion and adverse effect on a photosensitive layer. Constitution: A lithographic printing plate can be obtained by making use of a presensitized lithographic printing plate comprising a support having thereon a photosensitive layer containing o-quinonediazide compound, photo-degradable or photo-polymerizable resin and water-soluble resin and a light-shielding layer containing an infrared absorbing material and a material capable of absorbing the photosensitive wavelength of the photosensitive layer and by a process comprising ablating imagewise the light-shielding layer with laser light, overall-exposing with a ray active to the photosensitive layer to cause photoch…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.