The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Mar. 04, 1997
Filed:
Sep. 21, 1995
Maurice J Fitzgerald, Canton, MA (US);
John M Hardin, Jamaica Plain, MA (US);
Frederick R Kearney, Walpole, MA (US);
Rong-Chang Liang, Newton, MA (US);
Polaroid Corporation, Cambridge, MA (US);
Abstract
Described is the use of a plasticizing-permeation enhancing additive in negative-working, on-press developable lithographic printing plates. Briefly, a plasticizer, which is dispersible or soluble in press fountain and ink solutions and soluble in acrylic monomers and oligomers, are incorporated into a plate's photoresist at concentrations sufficient to enhance said resist's permeability to or diffusion by press solutions. Such additives make the photoresist more permeable to fountain solution prior to crosslinking, while being easily extracted with ink and fountain solution after crosslinking. In certain embodiments, a surfactant is added to facilitate the dispersion of hydrophobic remnants of removed resist material in the fountain solution, and thereby reduce scumming. Lithium salts may also be incorporated into the photoresist to disrupt hydrogen bonding of, for example, urethane acrylate polymers which tend to associate by hydrogen bonding.