Lithographic fountain solution containing mixed colloids
US4764213A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jun 16, 1986 |
| Grant date | Aug 16, 1988 |
| Priority date | — |
| Expiry date | Jun 16, 2006 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB41N3/08
- WIPO fieldTextile and paper machines
- WIPO sectorMechanical engineering
Abstract
A lithographic fountain solution concentrate is disclosed, the essential components of which comprises an aqueous mixture of: PA0 (a) from about 0.1 to 1.5 percent by weight of a water soluble film forming hydrophilic gum; PA0 (b) from about 0.75 to about 8.5 percent by weight of Polyvinyl Pyrrolidone; PA0 (c) from about 5.0 to about 30.0 percent by weight of a water soluble acid etchant; PA0 (d) from about 20.0 to about 50.0 percent by weight of a water soluble or water miscible glycol; and PA0 (e) from about 0.01 to about 1.25 percent by weight of a phosphate/phosphoric acid buffer system. The concentrate is adapted for further dilution by water to yield a fountain solution which when used in the printing process offers decreased scumming and blinding of printing plates while at the same time permitting a reduction in the amount of water applied to the plate. Improved print quality, reduced tendency to wet the paper, faster ink drying and improved ink/water balance is thereby achieved.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.