US4404074A
Expired / Lapsed
US
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Electrolytic stripping bath and process
Assignee: OMI International Corp
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Filing: 1982-05-27
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Granted: 1983-09-13
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Expires: 2002-05-27
Abstract
Abstract An improved electrolytic bath composition and process for stripping relatively thick copper, copper alloy, or chromium deposits from a ferrous basis metal comprising an aqueous solution having a pH of from about 1 to about 14 and consisting essentially of an amine, nitro, and/or nitrate stripping component; and sodium glucoheptonate present in an effective amount to inhibit attack of the basis metal. The solution may further include at least one bath soluble compound selected from the group consisting of malic acid, oxalic acid, and mixtures thereof, as well as the Group IA, IIA, and ammonium salts thereof, present in an effective amount, when combined with said sodium glucoheptonate, to inhibit attack of the basis metal; and/or a carboxylic acid buffering agent comprising at least one material selected from the group consisting of gluconic acid, lactic acid, tartaric acid, fumaric acid, citric acid, isoascorbic acid, succinic acid, acetic acid, and mixtures thereof, as well as the alkali metal and ammonium salts thereof. The stripping of the metal deposit is effected by immersion of the object in the bath while anodically charged and passing electric current through the bath to a cathode for a period of time sufficient to achieve the desired magnitude of stripping of the metal deposit.
Inventors
- 👤 Lillie C. Tomaszewski
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 02:15
CPC Classifications
C; C25; C25F; C25F5/00; C25D; C25D17/00; C25D17/005; C25D5/00; C25D5/48
Claims Analysis
Total Claims: 32
Claim 1
Independent Claim
95 words
An electrolytic stripping bath for stripping copper, copper alloy, or chromium deposits from a ferrous basis metal comprising an aqueous solution having a pH of from about 1 to about 14 and consisting essentially of a stripping component selected from the group consisting of (a) a bath soluble primary, secondary, and/or tertiary amine having a carbon content of C 1 to C 8 , (b) a bath soluble inorganic nitrate and/or organic nitro compound, and mixtures of (a) and (b); and sodium glucoheptonate present in an effective amount to inhibit attack of the basis metal.
Claim 2
Dependent Claim
95 words
An electrolytic stripping bath for stripping copper, copper alloy, or chromium deposits from a ferrous basis metal comprising an aqueous solution having a pH of from about 1 to about 14 and consisting essentially of a stripping component selected from the group consisting of (a) a bath soluble primary, secondary, and/or tertiary amine having a carbon content of C 1 to C 8 , (b) a bath soluble inorganic nitrate and/or organic nitro compound, and mixtures of (a) and (b); and sodium glucoheptonate present in an effective amount to inhibit attack of the basis metal.
Claim 3
Dependent Claim
25 words
The stripping bath as defined in claim 1 in which said sodium glucoheptonate is present in an amount of from about 1 g/L to saturation.
Claim 4
Dependent Claim
26 words
The stripping bath as defined in claim 1 in which said sodium glucoheptonate is present in an amount of from about 5 to about 50 g/L.
Claim 5
Dependent Claim
62 words
The stripping bath as defined in claim 1 in which said solution further contains at least one bath soluble compound selected from the group consisting of malic acid, oxalic acid, and mixtures thereof, as well as the Group IA, IIA, and ammonium salts thereof, present in an effective amount, when combined with said sodium glucoheptonate, to inhibit attack of the basis metal.
Claim 6
Dependent Claim
27 words
The stripping bath as defined in claim 4 in which said bath soluble compound is present in an amount of from about 1 to about 20 g/L.
Claim 7
Dependent Claim
42 words
The stripping bath as defined in claim 4 in which said bath soluble compound is malic acid which is present in an amount of about 10 g/L, and in which said sodium glucoheptonate is present in an amount of about 10 g/L.
Claim 8
Dependent Claim
19 words
The stripping bath as defined in claim 4 in which said solution further contains a carboxylic acid buffering agent.
Claim 9
Dependent Claim
55 words
The stripping bath as defined in claim 7 in which said carboxylic acid buffering agent comprises at least one material selected from the group consisting of gluconic acid, lactic acid, tartaric acid, fumaric acid, citric acid, isoascorbic acid, succinic acid, acetic acid, and mixtures thereof, as well as the alkali metal and ammonium salts thereof.
Claim 10
Dependent Claim
24 words
The stripping bath as defined in claim 7 in which said buffering agent is present in an amount of up to about 60 g/L.
Claim 11
Dependent Claim
26 words
The stripping bath as defined in claim 7 in which said buffering agent is present in an amount of from about 20 to about 40 g/L.
Claim 12
Dependent Claim
19 words
The stripping bath as defined in claim 1 in which said solution further contains a carboxylic acid buffering agent.
Claim 13
Dependent Claim
55 words
The stripping bath as defined in claim 11 in which said carboxylic acid buffering agent comprises at least one material selected from the group consisting of gluconic acid, lactic acid, tartaric acid, fumaric acid, citric acid, isoascorbic acid, succinic acid, acetic acid, and mixtures thereof, as well as the alkali metal and ammonium salts thereof.
Claim 14
Dependent Claim
24 words
The stripping bath as defined in claim 11 in which said buffering agent is present in an amount of up to about 60 g/L.
Claim 15
Dependent Claim
26 words
The stripping bath as defined in claim 11 in which said buffering agent is present in an amount of from about 20 to about 40 g/L.
Claim 16
Dependent Claim
18 words
The stripping bath as defined in claim 1 having a pH of from about 5.0 to about 7.5.
Claim 17
Dependent Claim
142 words
A process for electrolytically stripping copper, copper alloy, or chromium deposits from a ferrous basis metal which comprises the steps of immersing an object to be stripped in a stripping bath comprising an aqueous solution having a pH of from about 1 to about 14 and consisting essentially of a stripping component selected from the group consisting of (a) a bath soluble primary, secondary, and/or tertiary amine having a carbon content of C 1 to C 8 , (b) a bath soluble inorganic nitrate and/or organic nitro compound, and mixtures of (a) and (b); and sodium glucoheptonate present in an effective amount to inhibit attack of the basis metal; anodically charging the object; and passing electric current through the solution to a cathode for a period of time to achieve the desired magnitude of stripping of the metal deposit from the object.
Claim 18
Dependent Claim
142 words
A process for electrolytically stripping copper, copper alloy, or chromium deposits from a ferrous basis metal which comprises the steps of immersing an object to be stripped in a stripping bath comprising an aqueous solution having a pH of from about 1 to about 14 and consisting essentially of a stripping component selected from the group consisting of (a) a bath soluble primary, secondary, and/or tertiary amine having a carbon content of C 1 to C 8 , (b) a bath soluble inorganic nitrate and/or organic nitro compound, and mixtures of (a) and (b); and sodium glucoheptonate present in an effective amount to inhibit attack of the basis metal; anodically charging the object; and passing electric current through the solution to a cathode for a period of time to achieve the desired magnitude of stripping of the metal deposit from the object.
Claim 19
Dependent Claim
24 words
The process as defined in claim 16 in which said sodium glucoheptonate is present in an amount of from about 1 g/L to saturation.
Claim 20
Dependent Claim
25 words
The process as defined in claim 16 in which said sodium glucoheptonate is present in an amount of from about 5 to about 50 g/L.
Claim 21
Dependent Claim
61 words
The process as defined in claim 16 in which said solution further contains at least one bath soluble compound selected from the group consisting of malic acid, oxalic acid, and mixtures thereof, as well as the Group IA, IIA, and ammonium salts thereof, present in an effective amount, when combined with said sodium glucoheptonate, to inhibit attack of the basis metal.
Claim 22
Dependent Claim
26 words
The process as defined in claim 19 in which said bath soluble compound is present in an amount of from about 1 to about 20 g/L.
Claim 23
Dependent Claim
41 words
The process as defined in claim 19 in which said bath soluble compound is malic acid which is present in an amount of about 10 g/L, and in which said sodium glucoheptonate is present in an amount of about 10 g/L.
Claim 24
Dependent Claim
18 words
The process as defined in claim 19 in which said solution further contains a carboxylic acid buffering agent.
Claim 25
Dependent Claim
54 words
The process as defined in claim 22 in which said carboxylic acid buffering agent comprises at least one material selected from the group consisting of gluconic acid, lactic acid, tartaric acid, fumaric acid, citric acid, isoascorbic acid, succinic acid, acetic acid, and mixtures thereof, as well as the alkali metal and ammonium salts thereof.
Claim 26
Dependent Claim
23 words
The process as defined in claim 22 in which said buffering agent is present in an amount of up to about 60 g/L.
Claim 27
Dependent Claim
25 words
The process as defined in claim 22 in which said buffering agent is present in an amount of from about 20 to about 40 g/L.
Claim 28
Dependent Claim
18 words
The process as defined in claim 16 in which said solution further contains a carboxylic acid buffering agent.
Claim 29
Dependent Claim
54 words
The process as defined in claim 26 in which said carboxylic acid buffering agent comprises at least one material selected from the group consisting of gluconic acid, lactic acid, tartaric acid, fumaric acid, citric acid, isoascorbic acid, succinic acid, acetic acid, and mixtures thereof, as well as the alkali metal and ammonium salts thereof.
Claim 30
Dependent Claim
23 words
The process as defined in claim 26 in which said buffering agent is present in an amount of up to about 60 g/L.
Claim 31
Dependent Claim
25 words
The process as defined in claim 26 in which said buffering agent is present in an amount of from about 20 to about 40 g/L.
Claim 32
Dependent Claim
24 words
The process as defined in claim 16 including the further step of controlling the pH of said bath between about 5.0 to about 7.5.
References Cited (Backward Citations)
US4233124A
Cited
US4264420A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-09-12 | 1987-03-14 | 1987-09-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-09-12 | 1991-03-14 | 1991-09-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-09-12 | 1995-03-14 | 1995-09-13 | $7700.00 | Window Closed / Lapsed |