US4610759A
Expired / Lapsed
US
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Etching solution for and method of etching ferrimagnetic garnet compounds
Assignee: US Philips Corp
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Filing: 1985-05-03
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Granted: 1986-09-09
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Expires: 2005-05-03
Abstract
Abstract An etching solution for etching ferrimagnetic garnet compounds in which the etching solution comprises at least a strong mineral acid, for example H3PO4, and a reducing agent, for example one-or two-electron-donors.
Inventors
- 👤 Claus P. Klages
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 13:25
CPC Classifications
C; C09; C09K; C09K13/00; C09K13/04; C30; C30B; C30B29/00; C30B29/10; C30B29/16; C30B29/22; C30B29/28; C30B33/00
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
29 words
An etching solution comprising at least one strong mineral acid for etching ferrimagnetic garnet compounds, characterized in that it comprises additionally one- or two-electron donors as a reducing agent.
Claim 2
Dependent Claim
29 words
An etching solution comprising at least one strong mineral acid for etching ferrimagnetic garnet compounds, characterized in that it comprises additionally one- or two-electron donors as a reducing agent.
Claim 3
Dependent Claim
25 words
An etching solution as claimed in claim 1, characterized in that it comprises one- or two-electron donors in a concentration of 0.07 to 0.6 mol/l.
Claim 4
Dependent Claim
19 words
An etching solution as claimed in claim 1, characterized in that it comprises Fe 2+ as a reducing agent.
Claim 5
Dependent Claim
19 words
An etching solution as claimed in claim 1, characterized in that it comprises Ti 3+ as a reducing agent.
Claim 6
Dependent Claim
19 words
An etching solution as claimed in claim 1, characterized in that it comprises V 2+ as a reducing agent.
Claim 7
Dependent Claim
19 words
An etching solution as claimed in claim 1, characterized in that it comprises Sn 2+ as a reducing agent.
Claim 8
Dependent Claim
23 words
An etching solution as claimed in claim 1, characterized in that it comprises phosphoric acid H 3 PO 4 as a mineral acid.
Claim 9
Dependent Claim
45 words
An etching solution as claimed in claim 1, characterized in that it comprises as a mineral acid a mixture of phosphoric acid H 3 PO 4 in the form of its 85% aqueous solution with 10% hydrochloric acid HCl in a volume ratio of 2:1.
Claim 10
Dependent Claim
36 words
A method of etching ferrimagnetic garnet compounds while using the etching solution as claimed in claim 1, characterized in that etching is carried out at an etching temperature in the range from 20° to 120° C.
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) | 1989-09-08 | 1990-03-10 | 1990-09-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1993-09-08 | 1994-03-10 | 1994-09-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1997-09-08 | 1998-03-10 | 1998-09-09 | $7700.00 | Window Closed / Lapsed |