US4420366A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method for manufacturing shadow mask
Assignee: Toshiba Corp
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Filing: 1983-03-24
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Granted: 1983-12-13
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Expires: 2003-03-24
Abstract
Abstract A method for manufacturing a shadow mask by spraying an Fe-Ni alloy sheet with a ferric chloride solution to form apertures for passing an electron beam the ferric chloride solution is controlled to have 0.30±0.20% by weight of free hydrochloric acid within a ferric chloride solution temperature range between 40° C. and 70° C., to have a total amount of Fe ++ ions and Ni ++ ions of not more than 15% by weight, and to have a specific gravity which falls within a region bounded between a curve plotted according to a relation 1.461-(4.63×10 -4 T)-(1.96×10 -6 ×T 2 ) (where T is a ferric chloride solution temperature) and a curve plotted according to a relation 1.552+(7.79×10 -5 ×T)-(1.18×10 -5 ×T 2 ).
Inventors
- 👤 Koichiro Oka
- 👤 Hiroshi Tanaka
- 👤 Makoto Harigae
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 00:07
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/14; H01J9/142; C; C23; C23F; C23F1/00; C23F1/10; C23F1/14; C23F1/16; C23F1/26; C23F1/28
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
131 words
A method for manufacturing a shadow mask by spraying an Fe-Ni alloy sheet with a ferric chloride solution to form an aperture for passing an electron beam therethrough, wherein the ferric chloride solution is controlled to have a content of 0.30±0.20% by weight of free hydrochloric acid within a ferric chloride solution temperature range between 40° C. and 70° C., to have a total amount of Fe ++ ions and Ni ++ ions of not more than 15% by weight, and to have a specific gravity which falls within a region bounded between a curve plotted according to a relation 1.46l-(4.63×10 -4 ×T)-(1.96×10 -6 ×T 2 ) (where T is a ferric chloride solution temperature) and a curve plotted according to a relation 1.552 +(7.79×10 -5 ×T)-(1.18×10 -5 ×T 2 ).
Claim 2
Independent Claim
131 words
A method for manufacturing a shadow mask by spraying an Fe-Ni alloy sheet with a ferric chloride solution to form an aperture for passing an electron beam therethrough, wherein the ferric chloride solution is controlled to have a content of 0.30±0.20% by weight of free hydrochloric acid within a ferric chloride solution temperature range between 40° C. and 70° C., to have a total amount of Fe ++ ions and Ni ++ ions of not more than 15% by weight, and to have a specific gravity which falls within a region bounded between a curve plotted according to a relation 1.46l-(4.63×10 -4 ×T)-(1.96×10 -6 ×T 2 ) (where T is a ferric chloride solution temperature) and a curve plotted according to a relation 1.552 +(7.79×10 -5 ×T)-(1.18×10 -5 ×T 2 ).
Claim 3
Dependent Claim
30 words
A method according to claim 1, wherein the content of free hydrochloric acid is 0.30±0.l0% by weight within the ferric chloride solution temperature range between 40° C. and 70° C.
Claim 4
Dependent Claim
13 words
A method according to claim 1, wherein the Fe-Ni alloy comprises invar steel.
References Cited (Backward Citations)
US2684892A
Cited
US3824136A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-12-12 | 1987-06-13 | 1987-12-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-12-12 | 1991-06-13 | 1991-12-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-12-12 | 1995-06-13 | 1995-12-13 | $7700.00 | Window Closed / Lapsed |