US4179638A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cathode ray tube panel
Assignee: Corning Glass Works
•
Filing: 1978-06-29
•
Granted: 1979-12-18
•
Expires: 1998-06-29
Abstract
Abstract There is disclosed an improved glass panel for a cathode ray tube adapted to use in color television reception. The panel glass undergoes a minimum amount of compaction on reheating, has a strain point greater than 470° C., a liquidus below 900° C., and a composition selected from a family within the SiO 2 -Al 2 O 3 -MgO-CaO-SrO-BaO-PbO-Na 2 O-K 2 O field. Special additives in minor amounts include TiO 2 , CeO 2 , Sb 2 O 3 , As 2 O 3 , F, and oxide colorants.
Inventors
- 👤 David C. Boyd
- 👤 Henry E. Hagy
- 👤 David A. Thompson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 03:36
CPC Classifications
H; H01; H01J; H01J29/00; H01J29/86; H01J29/863
Claims Analysis
Total Claims: 4
Claim 1
Independent Claim
148 words
In a cathode ray tube for reception and display of color television comprising a display panel portion, a neck portion having an electron gun mounted therein, an intermediate funnel portion, and an electron mask having a pattern of perforations aligned with a pattern of phosphor configurations forming a screen on the panel, said panel consisting of a silicate glass having a low compaction when heated to temperatures between 400°-500° C., a strain point over 470° C., a liquidus below 900° C., and a composition, as calculated in weight percent from the batch on the oxide basis, chemically composed essentially of, in addition to silica, 1-3% Al 2 O 3 , 1.5-3% MgO, 2.5-4.5% CaO, 5-10% SrO, 3-10% BaO, 1-2.5% PbO, 6-10% Na 2 O, 4-8% K 2 O, the ratio of Na 2 O:K 2 O being at least 1:1, and the total content of SrO+BaO+CaO+MgO being 15-24%.
Claim 2
Dependent Claim
148 words
In a cathode ray tube for reception and display of color television comprising a display panel portion, a neck portion having an electron gun mounted therein, an intermediate funnel portion, and an electron mask having a pattern of perforations aligned with a pattern of phosphor configurations forming a screen on the panel, said panel consisting of a silicate glass having a low compaction when heated to temperatures between 400°-500° C., a strain point over 470° C., a liquidus below 900° C., and a composition, as calculated in weight percent from the batch on the oxide basis, chemically composed essentially of, in addition to silica, 1-3% Al 2 O 3 , 1.5-3% MgO, 2.5-4.5% CaO, 5-10% SrO, 3-10% BaO, 1-2.5% PbO, 6-10% Na 2 O, 4-8% K 2 O, the ratio of Na 2 O:K 2 O being at least 1:1, and the total content of SrO+BaO+CaO+MgO being 15-24%.
Claim 3
Dependent Claim
25 words
In a cathode ray tube in accordance with claim 1, the ratio of BaO:SrO being at least 1:1 in the composition of the glass panel.
Claim 4
Dependent Claim
21 words
In a cathode ray tube in accordance with claim 1, the composition of the glass panel containing up to 0.4% F.
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) | 1982-12-17 | 1983-06-18 | 1983-12-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-12-17 | 1987-06-18 | 1987-12-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-12-17 | 1991-06-18 | 1991-12-18 | $7700.00 | Window Closed / Lapsed |