US3798035A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making flexible printing plates
Assignee: Goodrich Corp
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Filing: 1972-10-06
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Granted: 1974-03-19
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Expires: 1992-10-06
Abstract
Abstract Soluble, crystalline, low molecular weight ethylene-vinyl acetate copolymers are sensitized, typically with aromatic ketones, and can be insolubilized by exposure to U.V. light (3,200-3,800A) which selectively cures the exposed areas. Uncured material is removed by cold solvent wash leaving exposed area as a raised surface. Plates for flexographic printing are prepared from these materials by this process.
Inventors
- 👤 R Varga
- 👤 T Szczepanski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 15:38
CPC Classifications
G; G03; G03F; G03F7/00; G03F7/004; G03F7/038
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
29 words
exposing the full reverse surface of said sheet to ultraviolet light (3,200-3,800 A.) to fully cure and insolubilize said reverse surface to a depth of 1 to 5 mils;
Claim 2
Dependent Claim
33 words
The process of claim 1 wherein the wash solvent is employed as a spray at 0* to 15* C. and 5 to 35 psi at a distance of 6-9 inches from the plate.
Claim 3
Dependent Claim
68 words
selectively exposing the front surface of said sheet through a developed high contrast negative, the exposed portions of which do not transmit light, to an ultraviolet light source emitting ultraviolet radiation in the range 3,200-3,800 A. thereby creating exposed and cured areas on said sheet beneath the unexposed portions of said negative and leaving unexposed and uncured areas on said sheet beneath the exposed portions of said negative;
Claim 4
Dependent Claim
9 words
A process of forming a flexible printing plate comprising
Claim 5
Dependent Claim
46 words
washing said exposed sheet in a wash solvent, whereby to remove the surface portions of said sheet which were protected from radiation, said solvent being at a temperature from 0* to 15*C., to achieve a washout depth on the said sheet of at least 15 mils;
Claim 6
Dependent Claim
5 words
drying said washed sheet; and,
Claim 7
Dependent Claim
26 words
exposing the entire front surface of said sheet to ultraviolet light (3,200-3,800 A.) to cure the portions of said front surface exposed by said wash solvent.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |