Patent EP0157738A1 successfully refreshed from Google Patents.
US4073708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Apparatus and method for regeneration of chromosulfuric acid etchants
Assignee: Boeing Co
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Filing: 1976-06-18
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Granted: 1978-02-14
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Expires: 1996-06-18
Abstract
Abstract A chromic-sulfuric etching solution for copper is regenerated in an etching container with a permeable diaphragm dividing the container into an etching chamber and a sulfuric acid containing chamber. Electric current passes between an anode electrode located in the etchant chamber and a cathode electrode located in the sulfuric acid chamber to regenerate the etchant in the anode containing chamber and to deposit copper on the cathode.
Inventors
- 👤 Jr. Hicks
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:08
CPC Classifications
C; C25; C25D; C25D21/00; C25D21/16; C23; C23F; C23F1/00; C23F1/46
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
136 words
An apparatus having a tank for etching copper in a chromic-sulfuric etchant and for regenerating the etchant and depositing out dissolved copper within the tank, the apparatus comprising: means for dividing an etchant tank into two compartments adapted to contain an aqueous copper etching hexavalent chromic oxide-sulfuric acid etchant in an etching compartment and adapted to contain an aqueous solution consisting essentially of alkali metal sulfate or sulfuric acid in a cathode compartment, a permeable membrane communicating between the two compartments, an anodic electrode located in the etching compartment, an electrode located in the cathode compartment, means for passing an electric current between the electrodes, and means for introducing a copper containing article into the etching compartment to permit simultaneous etching of the article regeneration of the etchant and deposition of copper in the etchant tank.
Claim 2
Independent Claim
136 words
An apparatus having a tank for etching copper in a chromic-sulfuric etchant and for regenerating the etchant and depositing out dissolved copper within the tank, the apparatus comprising: means for dividing an etchant tank into two compartments adapted to contain an aqueous copper etching hexavalent chromic oxide-sulfuric acid etchant in an etching compartment and adapted to contain an aqueous solution consisting essentially of alkali metal sulfate or sulfuric acid in a cathode compartment, a permeable membrane communicating between the two compartments, an anodic electrode located in the etching compartment, an electrode located in the cathode compartment, means for passing an electric current between the electrodes, and means for introducing a copper containing article into the etching compartment to permit simultaneous etching of the article regeneration of the etchant and deposition of copper in the etchant tank.
Claim 3
Dependent Claim
20 words
An apparatus as in claim 1 wherein the membrane is selected from material consisting essentially of polyester or perfluorosulfonic acid.
Claim 4
Dependent Claim
25 words
An apparatus as in claim 2 wherein the hexavalent chromic oxide comprises sodium dichromate and the aqueous solution in the cathode compartment is sulfuric acid.
Claim 5
Independent Claim
121 words
An apparatus for simultaneously and in the same container etching a copper article, regenerating the etchant and depositing copper dissolved in the etchant comprising: a first compartment having an anodic electrode adapted to be immersed in an etchant of aqueous hexavalent chromic oxide-sulfuric acid, a second compartment having a cathodic electrode adapted to be immersed in an aqueous solution of materials consisting essentially of alkali-metal sulfate or sulfuric acid, a diaphragm communicating between the two compartments, means for introducing a copper article into the etchant compartment, and means for imparting an electric current between the electrodes to regenerate the etchant and to deposit copper on the cathodic electrode at the same time the copper article is being etched in the container.
Claim 6
Independent Claim
121 words
An apparatus for simultaneously and in the same container etching a copper article, regenerating the etchant and depositing copper dissolved in the etchant comprising: a first compartment having an anodic electrode adapted to be immersed in an etchant of aqueous hexavalent chromic oxide-sulfuric acid, a second compartment having a cathodic electrode adapted to be immersed in an aqueous solution of materials consisting essentially of alkali-metal sulfate or sulfuric acid, a diaphragm communicating between the two compartments, means for introducing a copper article into the etchant compartment, and means for imparting an electric current between the electrodes to regenerate the etchant and to deposit copper on the cathodic electrode at the same time the copper article is being etched in the container.
Claim 7
Dependent Claim
112 words
A process for etching copper in hexavalent chromic oxide-sulfuric acid etchant while simultaneously and in the same container regenerating the etchant and depositing out copper dissolved in the etchant, the steps comprising: introducing an anodic electrode into an aqueous hexavalent chromic oxide-sulfuric acid etchant, utilizing a permeable diaphragm as a barrier to contain the etchant, introducing an aqueous solution selected from sulfuric acid or an alkali metal sulfate on an opposite side of the diaphragm, introducing a cathodic electrode in the aqueous solution immersing a copper article in the etchant, and passing an electric current between the electrodes for regenerating the etchant at the anode and for depositing copper on the cathode.
Claim 8
Dependent Claim
112 words
A process for etching copper in hexavalent chromic oxide-sulfuric acid etchant while simultaneously and in the same container regenerating the etchant and depositing out copper dissolved in the etchant, the steps comprising: introducing an anodic electrode into an aqueous hexavalent chromic oxide-sulfuric acid etchant, utilizing a permeable diaphragm as a barrier to contain the etchant, introducing an aqueous solution selected from sulfuric acid or an alkali metal sulfate on an opposite side of the diaphragm, introducing a cathodic electrode in the aqueous solution immersing a copper article in the etchant, and passing an electric current between the electrodes for regenerating the etchant at the anode and for depositing copper on the cathode.
Claim 9
Independent Claim
115 words
A method of etching copper in a chromate-sulfuric etchant and at the same time and in the same container regenerating the etchant while depositing etchant dissolved copper, the steps comprising: dividing a container into two chambers, utilizing a diaphragm over at least part of an area dividing the chambers, introducing an aqueous hexavalent chromic oxide-sulfuric acid etchant and an anodic electrode in one chamber, introducing an aqueous solution selected from materials consisting essentially of an alkali metal sulfate or sulfuric acid and also a cathodic electrode in the second chamber, immersing a copper article in the etchant, and passing an electric current between the electrodes to regenerate the etchant and deposit copper on the cathode.
Claim 10
Independent Claim
115 words
A method of etching copper in a chromate-sulfuric etchant and at the same time and in the same container regenerating the etchant while depositing etchant dissolved copper, the steps comprising: dividing a container into two chambers, utilizing a diaphragm over at least part of an area dividing the chambers, introducing an aqueous hexavalent chromic oxide-sulfuric acid etchant and an anodic electrode in one chamber, introducing an aqueous solution selected from materials consisting essentially of an alkali metal sulfate or sulfuric acid and also a cathodic electrode in the second chamber, immersing a copper article in the etchant, and passing an electric current between the electrodes to regenerate the etchant and deposit copper on the cathode.
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) | 1981-02-13 | 1981-08-15 | 1982-02-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1985-02-13 | 1985-08-15 | 1986-02-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1989-02-13 | 1989-08-15 | 1990-02-14 | $7700.00 | Window Closed / Lapsed |