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US4058431A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of etching copper and copper alloys

Assignee: Hollmuller Hans Maschinenbau GmbH and Co
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Filing: 1975-10-20
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Granted: 1977-11-15
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Expires: 1995-10-20
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Abstract

Abstract A method of etching copper and copper alloys by means of an ammoniacal etching solution containing chloride ions and for regenerating this etching solution during this etching process by adding an ammoniacal compound, for example, in the form of ammonium hydroxide or ammonia gas, as well as hydrochloric acid and water to the etching solution in accordance with continuous measurements of the pH-value and the specific gravity of the etching solution.

Inventors

  • 👤 Rainer Haas

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-23 19:10
CPC Classifications
C; C23; C23F; C23F1/00; C23F1/46; Y; Y10; Y10T; Y10T137/00; Y10T137/0318; Y10T137/0324; Y10T137/0329

Claims Analysis

Total Claims: 7
Claim 1
Independent Claim 112 words
A method of etching copper and copper alloys, comprising the steps of: treating copper or a copper alloy with an etching medium consisting of an ammoniacal etching solution containing chloride ions, thereby producing a copper-I compound; regenerating the copper-I compound by reacting therewith a chloro compound and by the addition of water to said solution at a rate controlled in dependence upon the rate of formation of said copper-I compounds, the regeneration rate being controlled at least in part by monitoring the specific gravity of the solution; and supplying to said solution as amount of ammoniacal compound such that the pH value of the latter is maintained at about 8.5 to 10.0.
Claim 2
Independent Claim 112 words
A method of etching copper and copper alloys, comprising the steps of: treating copper or a copper alloy with an etching medium consisting of an ammoniacal etching solution containing chloride ions, thereby producing a copper-I compound; regenerating the copper-I compound by reacting therewith a chloro compound and by the addition of water to said solution at a rate controlled in dependence upon the rate of formation of said copper-I compounds, the regeneration rate being controlled at least in part by monitoring the specific gravity of the solution; and supplying to said solution as amount of ammoniacal compound such that the pH value of the latter is maintained at about 8.5 to 10.0.
Claim 3
Dependent Claim 36 words
The method defined in claim 1 wherein the addition of at least one of said chloro and ammoniacal compounds to the solution is carried out in part as a function of the color of the solution.
Claim 4
Dependent Claim 36 words
The method defined in claim 1 wherein the addition of at least one of said chloro and ammoniacal compounds to the solution is carried out in part as a function of the pH of the solution.
Claim 5
Dependent Claim 40 words
The method defined in claim 1 wherein said ammoniacal compound selected from the group which consists of ammonium hydroxide and ammonia gas, said chloro compound being selected from the group which consists of hydrogen chloride, ammonium chloride and sodium chloride.
Claim 6
Dependent Claim 29 words
The method defined in claim 4 wherein the copper content per liter of the etching medium is maintained at a substantially constant value by the addition thereto of water.
Claim 7
Dependent Claim 25 words
The method defined in claim 5 wherein the molar ratio of the chloro compound to the ammoniacal compound is maintained at substantially 1 to 2.

References Cited (Backward Citations)

US3592715A Cited
US3933544A Cited
US3705061A Cited
US3753818A Cited
US3775202A Cited
US3816306A Cited
US3951711A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1980-11-14 1981-05-16 1981-11-15 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1984-11-14 1985-05-16 1985-11-15 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1988-11-14 1989-05-16 1989-11-15 $7700.00 Window Closed / Lapsed

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