Patent DE810507C successfully refreshed from Google Patents.
Patent US4567131A successfully refreshed from Google Patents.
US4567131A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lithographic printing plates
Assignee: Agfa Gevaert NV
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Filing: 1984-07-11
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Granted: 1986-01-28
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Expires: 2004-07-11
Abstract
Abstract A lithographic printing plate having metallic silver image areas is treated with a proteolytic enzyme and an oleophilizing compound to improve ink receptivity.
Inventors
- 👤 Philip J. Watkiss
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:19
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/06; G03F7/063
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
33 words
A finishing composition for treating a lithographic printing plate having image areas of metallic silver, the composition comprising (i) a proteolytic enzyme and (ii) a compound capable of rendering the image areas oleophilic.
Claim 2
Dependent Claim
33 words
A finishing composition for treating a lithographic printing plate having image areas of metallic silver, the composition comprising (i) a proteolytic enzyme and (ii) a compound capable of rendering the image areas oleophilic.
Claim 3
Dependent Claim
19 words
A composition as claimed in claim 1 wherein the enzyme is trypsin, pepsin, ficin, papain or a bactericidal proteinase.
Claim 4
Dependent Claim
14 words
A composition as claimed in claim 1 wherein said compound is a mercapto compound.
Claim 5
Dependent Claim
14 words
A composition as claimed in claim 3 wherein said compound is 2-mercaptobenzthiazole or phenylmercaptotetrazole.
Claim 6
Dependent Claim
14 words
A composition as claimed in claim 1 wherein said compound is a cationic surfactant.
Claim 7
Dependent Claim
17 words
A composition as claimed in claim 5 wherein said compound is cetyltrimethyl ammonium bromide or cetylpyridinium chloride.
Claim 8
Dependent Claim
14 words
A composition as claimed in claim 1 and additionally including a lithographic desensitizing compound.
Claim 9
Dependent Claim
17 words
A composition as claimed in claim 7, wherein said lithographic desensitizing compound is gum arabic or dextrin.
Claim 10
Independent Claim
35 words
A method of treating a lithographic printing plate having image areas of metallic silver, the method comprising applying a proteolytic enzyme and subsequently or simultaneously applying a compound capable of rendering the image areas oleophilic.
Claim 11
Independent Claim
35 words
A method of treating a lithographic printing plate having image areas of metallic silver, the method comprising applying a proteolytic enzyme and subsequently or simultaneously applying a compound capable of rendering the image areas oleophilic.
Claim 12
Dependent Claim
15 words
A method according to claim 9, comprising simultaneously or subsequently applying a lithographic desensitizing compound.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1989-01-27 | 1989-07-29 | 1990-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-01-27 | 1993-07-29 | 1994-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-01-27 | 1997-07-29 | 1998-01-28 | $7700.00 | Window Closed / Lapsed |