Patent US3033725A successfully refreshed from Google Patents.
US3033725A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Powderless etching of copper plate
Assignee: Photo-Engravers Res Inc
•
Filing: 1958-05-02
•
Granted: 1962-05-08
•
Expires: 1978-05-02
Abstract
No abstract record available.
Inventors
- 👤 Phillip M Daugherty
- 👤 Henry C Vaughn
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:18
CPC Classifications
B; B41; B41C; B41C1/00; B41C1/02; C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
IN A PROCESS FOR THE ETCHING OF PHOTOENGRAVING COPPER HAVING A PORTION OF ITS SURFACE MASKED WITH A RESISTANT COATING, THE ETCHING BEING BY CONTACTING THE PHOTOENGRAVING COPPER WITH FERRIC CHLORIDE ETCHING SOLUTION, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE FERRIC CHLORIDE SOLUTION A FILM-FORMER SELECTED FROM THE GROUP CONSISTING OF SALTS OF FORMAMIDINE DISULFIDE AND SALTS OF SUBSTITUTED FORMAMIDINE DESULFIDE, AND CONTACTING THE UNMASKED SURFACE OF THE PHOTOENGRAVING COPPER WITH SAID ETCHING SOLUTION.
Claim 2
Dependent Claim
74 words
IN A PROCESS FOR THE ETCHING OF PHOTOENGRAVING COPPER HAVING A PORTION OF ITS SURFACE MASKED WITH A RESISTANT COATING, THE ETCHING BEING BY CONTACTING THE PHOTOENGRAVING COPPER WITH FERRIC CHLORIDE ETCHING SOLUTION, THE IMPROVEMENT WHICH COMPRISES ADDING TO THE FERRIC CHLORIDE SOLUTION A FILM-FORMER SELECTED FROM THE GROUP CONSISTING OF SALTS OF FORMAMIDINE DISULFIDE AND SALTS OF SUBSTITUTED FORMAMIDINE DESULFIDE, AND CONTACTING THE UNMASKED SURFACE OF THE PHOTOENGRAVING COPPER WITH SAID ETCHING SOLUTION.
References Cited (Backward Citations)
US2684892A
Cited
US2746848A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1965-05-07 | 1965-11-06 | 1966-05-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1969-05-07 | 1969-11-06 | 1970-05-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1973-05-07 | 1973-11-06 | 1974-05-08 | $7700.00 | Window Closed / Lapsed |