US4391916A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Alkali-free glass for photoetching mask
Assignee: Hoya Corp
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Filing: 1982-02-24
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Granted: 1983-07-05
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Expires: 2002-02-24
Abstract
Abstract An alkali-free glass composition for a photoetching mask is described, which comprises, all by mol, 55 to 65% SiO 2 , 7 to 11% Al 2 O 3 , 1 to 11% PbO, 7 to 20% CaO, 3 to 13% MgO, 3 to 13% ZnO, 0 to 3% ZrO 2 , 0 to 3% F 2 , 0 to 5% As 2 O 3 , and 0 to 5% Sb 2 O 3 . This glass is free from defects such as pinholes, has a relatively low coefficient of thermal expansion and contains no air bubbles, and a photoetching mask composed of the glass composition.
Inventors
- 👤 Kenji Nakagawa
- 👤 Isao Masuda
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 01:07
CPC Classifications
G; G03; G03F; G03F1/00; G03F1/60; C; C03; C03C; C03C3/00; C03C3/04; C03C3/076; C03C3/102; C03C3/105; C03C3/11; C03C3/112
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
73 words
An alkali-free glass for a photoetching mask, consisting essentially of, 55 to 65% SiO 2 , 7 to 11% Al 2 O 3 , 1 to 11% PbO, 7 to 20% CaO, 3 to 13% MgO, 3 to 13% ZnO, 0 to 3% ZrO 2 , 0 to 3% F 2 , 0 to 5% As 2 O 3 and 0 to 5% Sb 2 O 3 , wherein all percents are molar.
Claim 2
Dependent Claim
73 words
An alkali-free glass for a photoetching mask, consisting essentially of, 55 to 65% SiO 2 , 7 to 11% Al 2 O 3 , 1 to 11% PbO, 7 to 20% CaO, 3 to 13% MgO, 3 to 13% ZnO, 0 to 3% ZrO 2 , 0 to 3% F 2 , 0 to 5% As 2 O 3 and 0 to 5% Sb 2 O 3 , wherein all percents are molar.
Claim 3
Dependent Claim
76 words
A photoetching mask, consisting essentially of an alkali-free glass which consists essentially of 55 to 65% SiO 2 , 7 to 11% Al 2 O 3 , 1 to 11% PbO, 7 to 20% CaO, 3 to 13% MgO, 3 to 13% ZnO, 0 to 3% ZrO 2 , 0 to 3% F 2 , 0 to 5% As 2 O 3 and 0 to 5% Sb 2 O 3 , wherein all percents are molar.
Claim 4
Dependent Claim
76 words
A photoetching mask, consisting essentially of an alkali-free glass which consists essentially of 55 to 65% SiO 2 , 7 to 11% Al 2 O 3 , 1 to 11% PbO, 7 to 20% CaO, 3 to 13% MgO, 3 to 13% ZnO, 0 to 3% ZrO 2 , 0 to 3% F 2 , 0 to 5% As 2 O 3 and 0 to 5% Sb 2 O 3 , wherein all percents are molar.
References Cited (Backward Citations)
US3069294A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1986-07-04 | 1987-01-03 | 1987-07-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1990-07-04 | 1991-01-03 | 1991-07-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1994-07-04 | 1995-01-03 | 1995-07-05 | $7700.00 | Window Closed / Lapsed |