US4545918A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Stabilization of aqueous solutions containing hydrogen peroxide, hydrofluoric acid and metal ions
Assignee: Arkema France SA
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Filing: 1983-12-28
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Granted: 1985-10-08
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Expires: 2003-12-28
Abstract
Abstract Process for improving the stability of aqueous solutions containing hydrogen peroxide, metal ions and hydrofluoric acid which can be partially in the form of salts, comprising adding to the said solution at least one hydroxide selected from alkali metal hydroxides, ammonium hydroxide, or mixtures thereof in an amount which is insufficient to neutralize all the acidity present. The resultant novel stabilized solutions according to the invention are used in the surface treatment of metals especially of stainless steels.
Inventors
- 👤 Christian Pralus
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 16:06
CPC Classifications
C; C23; C23G; C23G1/00; C23G1/02; C01; C01B; C01B15/00; C01B15/01; C01B15/037; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F3/00; C23F3/04; C23F3/06
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
86 words
The process for improving the stability of an aqueous solution used to treat metal surfaces and containing hydrogen peroxide, metal ions and hydrofluoric acid which can be partially in the form of salts, which comprises adding to the said solution at least one hydroxide selected from alkali metal hydroxides, ammonium hydroxide, and mixtures thereof in an amount which is insufficient to neutralize all the acidity present such that said hydrofluoric acid is at a concentration, expressed as total fluoride, of more than 38 grams per liter.
Claim 2
Dependent Claim
86 words
The process for improving the stability of an aqueous solution used to treat metal surfaces and containing hydrogen peroxide, metal ions and hydrofluoric acid which can be partially in the form of salts, which comprises adding to the said solution at least one hydroxide selected from alkali metal hydroxides, ammonium hydroxide, and mixtures thereof in an amount which is insufficient to neutralize all the acidity present such that said hydrofluoric acid is at a concentration, expressed as total fluoride, of more than 38 grams per liter.
Claim 3
Dependent Claim
23 words
The process of claim 1, wherein the amount of the said hydroxide is between about 0.1 and 2 moles per liter of solution.
Claim 4
Dependent Claim
25 words
The process of claims 1 or 2, wherein said solution contains hydrogen peroxide at a concentration of between about 5 and 150 grams per liter.
Claim 5
Dependent Claim
90 words
A stabilized aqueous solution for the surface treatment of metals comprising hydrogen peroxide, metal ions and hydrofluoric acid which can be partially in the form of salts; all in an amount sufficient for said surface treatment, and a stabilizer comprising at least one hydroxide selected from an alkali metal hydroxide, ammonium hydroxide, or mixtures thereof in an amount which is insufficient to neutralize all the acidity present in said solution such that said hydrofluoric acid is at a concentration, expressed as total fluoride, of more than 38 grams per liter.
Claim 6
Dependent Claim
90 words
A stabilized aqueous solution for the surface treatment of metals comprising hydrogen peroxide, metal ions and hydrofluoric acid which can be partially in the form of salts; all in an amount sufficient for said surface treatment, and a stabilizer comprising at least one hydroxide selected from an alkali metal hydroxide, ammonium hydroxide, or mixtures thereof in an amount which is insufficient to neutralize all the acidity present in said solution such that said hydrofluoric acid is at a concentration, expressed as total fluoride, of more than 38 grams per liter.
Claim 7
Dependent Claim
24 words
The stabilized aqueous solution of claim 4 wherein the amount of said hydroxide is between about 0.1 and 2 moles per liter of solution.
Claim 8
Dependent Claim
27 words
The stabilized aqueous solution of claims 4 or 5 wherein said solution contains hydrogen peroxide at a concentration of between about 5 and 150 grams per liter.
Claim 9
Dependent Claim
23 words
The process of treating the surface of metals to clean or chemically polish the same comprising applying thereto the solution of claim 4.
Claim 10
Dependent Claim
12 words
The process of claim 7 wherein said metal is a stainless steel.
References Cited (Backward Citations)
FR1383066A
Cited
US3296141A
Cited
FR1472467A
Cited
JPS4829455B1
Cited
US3841905A
Cited
US3756957A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1988-10-07 | 1989-04-08 | 1989-10-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1992-10-07 | 1993-04-08 | 1993-10-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1996-10-07 | 1997-04-08 | 1997-10-08 | $7700.00 | Window Closed / Lapsed |