US4101322A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Lithographic plate ink receptivity improving composition and method
Assignee: EIDP Inc
•
Filing: 1977-01-24
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Granted: 1978-07-18
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Expires: 1997-01-24
Abstract
Abstract A composition for improving the ink receptivity of lithographic printing images comprises an organic solvent liquid capable of softening the surface of the printing image and a film forming alkali-resistant oleophilic material such as a liquid hydrocarbon solution of a normally solid hydrocarbon or fat. The composition is for use in the case where the printing image is formed by alkaline development of an image-wise exposed radiation sensitive coating such as a phenol formaldehyde resin in admixture with a sensitiser. The composition may be applied before exposure to form an alkali resistant oleophilic layer on the radiation sensitive coating or it may be applied after image-wise exposure but before alkali development.
Inventors
- 👤 Leslie Edward Lawson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 10:36
CPC Classifications
B; B41; B41N; B41N3/00; B41N3/08
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
131 words
A composition for improving the ink receptivity of a lithographic printing plate having a printing image formed by alkali-development of an image-wise exposed radiation sensitive layer which composition comprises (i) an organic solvent liquid capable of softening the surface of the printing image, said solvent being selected from the group consisting of alcohols, esters and ketones and comprising from about 2% to 20% by weight of the composition and (ii) a film forming alkali-resistant oleophilic material which is a liquid hydrocarbon solution of a normally solid material selected from the group consisting of hydrocarbons, fats and mixtures of hydrocarbons and fats, said liquid hydrocarbon comprising from about 45% to 85% by weight of the composition and said normally solid material comprising from about 5% to 25% by weight of the composition.
Claim 2
Dependent Claim
131 words
A composition for improving the ink receptivity of a lithographic printing plate having a printing image formed by alkali-development of an image-wise exposed radiation sensitive layer which composition comprises (i) an organic solvent liquid capable of softening the surface of the printing image, said solvent being selected from the group consisting of alcohols, esters and ketones and comprising from about 2% to 20% by weight of the composition and (ii) a film forming alkali-resistant oleophilic material which is a liquid hydrocarbon solution of a normally solid material selected from the group consisting of hydrocarbons, fats and mixtures of hydrocarbons and fats, said liquid hydrocarbon comprising from about 45% to 85% by weight of the composition and said normally solid material comprising from about 5% to 25% by weight of the composition.
Claim 3
Dependent Claim
18 words
A composition as claimed in claim 1 wherein the alcohol is ethanol, iso-propanol, n-butanol, 2-ethyl hexanol or 1-octanol.
Claim 4
Dependent Claim
18 words
A composition as claimed in claim 1 wherein the ester is n-hexyl acetate, diethyl phthalate or diethyl carbonate.
Claim 5
Dependent Claim
26 words
A composition as claimed in claim 1 wherein the normally solid material comprises gilsonite, bitumen, beeswax, paraffin wax, tallow or mixture of two or more thereof.
Claim 6
Dependent Claim
19 words
A composition as claimed in claim 1 and additionally including up to 20% by weight of pigment and/or dye.
Claim 7
Dependent Claim
66 words
A method of processing a radiation sensitive plate comprising a layer of radiation sensitive material which is developable by an alkaline developer after image-wise exposure, which method comprises: (a) image-wise exposing the radiation sensitive layer, (b) treating the image-wise exposed layer with a composition as claimed in claim 1 and (c) developing the treated layer with an alkaline developer to leave an image on the plate.
Claim 8
Dependent Claim
21 words
A method according to claim 6 wherein the radiation sensitive layer comprises a mixture of a phenol-formaldehyde resin and a sensitiser.
Claim 9
Dependent Claim
25 words
A method according to claim 7 and comprising the additional step of heating the plate after development to a temperature sufficient to burn-in said plate.
Claim 10
Dependent Claim
38 words
A method according to claim 8 and comprising the additional step of providing a water soluble layer on the plate after development to prevent contaminating residues from contacting the non-image areas of the plate during the heating step.
Claim 11
Dependent Claim
39 words
A radiation sensitive plate comprising a substrate; a coating on the substrate of a radiation sensitive material which is developable by an alkaline developer after image-wise exposure; and, on said coating, a layer of solid alkali resistant oleophilic material.
Claim 12
Dependent Claim
39 words
A radiation sensitive plate comprising a substrate; a coating on the substrate of a radiation sensitive material which is developable by an alkaline developer after image-wise exposure; and, on said coating, a layer of solid alkali resistant oleophilic material.
Claim 13
Dependent Claim
39 words
A plate as claimed in claim 10 wherein the radiation sensitive layer comprises a mixture of a phenol formaldehyde resin and a sensitiser and the solid alkali resistant oleophilic material comprises a hydrocarbon, a fat, or a mixture thereof.
Claim 14
Dependent Claim
15 words
A composition as claimed in claim 1 wherein the ketone is 2,6-dimethyl-4-heptanone, 3-methyl-2-pentanone or 4-methyl-2-pentanone.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1981-07-17 | 1982-01-16 | 1982-07-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-07-17 | 1986-01-16 | 1986-07-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-07-17 | 1990-01-16 | 1990-07-18 | $7700.00 | Window Closed / Lapsed |