US3772105A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Continuous etching process
Assignee: Shipley Co Inc
•
Filing: 1972-03-16
•
Granted: 1973-11-13
•
Expires: 1992-03-16
Abstract
Abstract This invention relates to a continuous process for etching cuprous metal which process comprises etching copper with the etchants of the invention, precipitation and removal of the copper from the etchant and regeneration of the etchant making the same available for further use. The etchant used comprises complexed cupric ions as an oxidant. In practice, the etchant is used to etch copper until the dissolved copper concentration reaches a predetermined point, typically from 10 to 24 ounces per gallon of solution. At this point, the etchant is circulated in a loop where it is treated to precipitate dissolved copper, the precipitate is removed and the etchant is returned to the etching apparatus for further use.
Inventors
- 👤 C Shipley
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 00:51
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/46
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
28 words
The process of claim 1 containing as an exaltant for said etchant at least one member selected from the group of chloride ions, bromide ions and ammonium ions.
Claim 2
Dependent Claim
17 words
The process of claim 2 where the etchant has a pH varyiNg between about 6 and 8.
Claim 3
Dependent Claim
17 words
The process of claim 2 where the etchant has a pH varying between about 7 and 7.8.
Claim 4
Dependent Claim
42 words
The process of claim 3 where the etchant contains cupric ions present initially in an amount of from 0.1 to 1.2 moles per liter and complexing agent present in an amount sufficient to at least complex with all of said cupric ions.
Claim 5
Dependent Claim
26 words
The process of claim 3 where the etchant contains chloride or bromide ions in an amount of from 0.2 to 2.0 moles per liter of solution.
Claim 6
Dependent Claim
25 words
The process of claim 3 where the etchant also contains ammonium ions in an amount of from 0.5 to 5.0 moles per liter of solution.
Claim 7
Dependent Claim
40 words
The process of claim 3 where the etchant contains chloride ions in an amount of from 0.2 to 2.0 moles per liter of solution and ammonium ions in an amount of from 0.5 to 5.0 moles per liter of solution.
Claim 8
Dependent Claim
29 words
The process of claim 8 where in the etchant, the log of the stability constant (K1) of the copper (II) complex does not exceed about 18 at 25* C.
Claim 9
Dependent Claim
13 words
The process of claim 8 where the etchant contains an amine complexing agent.
Claim 10
Dependent Claim
15 words
The process of claim 8 where the etchant contains as a complexing agent an alkanolamine.
Claim 11
Dependent Claim
64 words
The process of claim 3 comprising continuously etching copper with said etchant, enhancing the precipitation of dissolved copper from solution by at least one of the steps of cooling said etchant and lowering the pH of said etchant, removing precipitate from said etchant, replenishing said etchant including adjustment of pH to the extent necessary, etching additional copper with said etchant and repeating said process.
Claim 12
Dependent Claim
33 words
The process of claim 12 where the etchant contains from about 10 to 24 ounces of dissolved copper per gallon of solution prior to the step of enhancing the precipitation of dissolved copper.
Claim 13
Dependent Claim
35 words
The process of claim 12 where the etchant contains from about 14 to 20 ounces of dissolved copper per gallon of solution prior to the step of enhancing the precipitation of dissolved copper from solution.
Claim 14
Dependent Claim
19 words
The process of claim 12 where copper is precipitated by cooling the etchant and the addition of hydrochloric acid.
Claim 15
Dependent Claim
16 words
The process of claim 15 where the etchant is cooled to a maximum of 25* F.
Claim 16
Dependent Claim
15 words
The process of claim 15 where the etchant is cooled between 5* and 10* F.
Claim 17
Dependent Claim
26 words
The process of claim 15 where the acid is added in an amount of from 1 to 3 moles per mole of copper to be removed.
Claim 18
Dependent Claim
26 words
The process of claim 15 where the acid is added in an amount of from 1 to 2 moles per mole of copper to be removed.
Claim 19
Dependent Claim
27 words
The process of claim 15 where the dissolved copper content in the etchant is reduced to no less than 4 ounces of copper per gallon of etchant.
Claim 20
Dependent Claim
26 words
The process of claim 15 where the etchant is heated back to operating temperature and the etchant is aerated to convert cuprous ions to cupric form.
Claim 21
Dependent Claim
25 words
The process of claim 15 where replenishers are added to the etchant to replace those additives lost through drag-out prior to repeating the etching process.
Claim 22
Dependent Claim
32 words
The process of claim 15 where the copper is etched, the etchant is passed out of a spray etcher containing said etchant to remove said precipitate, and recycled back to said etcher.
Claim 23
Dependent Claim
44 words
The process of claim 15 where the etchant is passed continuously from an etcher containing said etchant to means to remove precipitate and back to said etcher and where copper is dissolved at about the same rate as it is removed as a precipitate.
Claim 24
Dependent Claim
12 words
The process of claim 24 where copper is removed in sedimentation tanks.
Claim 25
Dependent Claim
11 words
The process of claim 24 where copper is removed by centrifugation.
Claim 26
Dependent Claim
11 words
The process of claim 24 where copper is removed by filtration.
References Cited (Backward Citations)
US3083129A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-11-12 | 1977-05-14 | 1977-11-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-11-12 | 1981-05-14 | 1981-11-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-11-12 | 1985-05-14 | 1985-11-13 | $7700.00 | Window Closed / Lapsed |