US4366252A Expired / Lapsed US ⏱️ 0.0 years remaining

Fluorine-free, zirconia-free, X-ray absorbing silica based glass, containing oxides of lead, barium and strontium plus oxides of calcium, magnesium, sodium, potassium, cerium, titanium, arsenic and antimony

Assignee: Techneglas LLC

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Filing: 1980-03-13

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Granted: 1982-12-28

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Expires: 2000-03-13

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Abstract

Abstract A fluorine-free glass composition is disclosed especially adapted for forming the faceplate of a cathode ray tube such as a television tube. The glass is silica based and includes a fluorine-free flux and an X-ray absorber which may comprise lead oxide, barium oxide, strontium oxide, and mixtures thereof. Optionally, the glass may contain still other oxides to impart desired physical properties. The absence of fluorine avoids the usual problems of that ingredient in melting and processing the glass. In addition, the resultant glass as a faceplate provides improved protection to a viewer of a cathode ray tube by excellent absorption of X-rays.

Inventors

👤 Edward A. Weaver

Bibliographic Details

Application Number —

Jurisdiction US

Data Source google_patents

Last Synchronized 2026-10-29 23:01

CPC Classifications

C; C03; C03C; C03C4/00; C03C4/08; C03C4/087; C03C3/00; C03C3/04; C03C3/076; C03C3/083; C03C3/085; C03C3/087; C03C3/095

Claims Analysis

Total Claims: 6

Claim 1

Independent Claim 62 words

A fluorine-free and zirconia-free glass having a linear absorption coefficient of at least 28 and substantially the following composition in weight percent: ______________________________________ Lead oxide 41/2% Barium oxide 5% Strontium oxide 8% Na.sub.2 O 7% K.sub.2 O 73/4% Silica 611/4% Aluminum oxide 1% Calcium oxide 3% Magnesium oxide 1/4% Titanium oxide 1/2% Antimony oxide 1/2% Arsenic oxide 1/4% Cerium oxide 1/4%. ______________________________________

Claim 2

Dependent Claim 62 words

Claim 3

Dependent Claim 62 words

A fluorine-free and zirconia-free glass having a linear absorption coefficient of at least 28 and substantially the following composition in weight percent: ______________________________________ Lead oxide 23/4% Barium oxide 21/4% Strontium oxide 9% Na.sub.2 O 73/4% K.sub.2 O 81/4% Silica 64% Aluminum oxide 1% Calcium oxide 3% Magnesium oxide 1/4% Titanium oxide 1/2% Antimony oxide 1/2% Arsenic oxide 1/4% Cerium oxide 1/4% ______________________________________

Claim 4

Dependent Claim 62 words

A fluorine-free and zirconia-free glass having a linear absorption coefficient of at least 28 and substantially the following composition in weight percent: ______________________________________ Lead oxide 23/4% Barium oxide 21/4% Strontium oxide 9% Na.sub.2 O 73/4% K.sub.2 O 81/4% Silica 64% Aluminum oxide 1% Calcium oxide 3% Magnesium oxide 1/4% Titanium oxide 1/2% Antimony oxide 1/2% Arsenic oxide 1/4% Cerium oxide 1/4% ______________________________________

Claim 5

Dependent Claim 61 words

A fluorine-free and zirconia-free glass having a linear absorption coefficient of at least 28 and substantially the following composition in weight percent: ______________________________________ Lead oxide 3% Barium oxide 21/4% Strontium 91/4% Na.sub.2 O 73/4% K.sub.2 O 81/4% Silica 64% Aluminum oxide 1% Calcium oxide 31/4% Magnesium oxide 1/4% Titanium oxide 1/2% Antimony oxide 1/2% Arsenic oxide 1/4% Cerium oxide 1/4% ______________________________________

Claim 6

Dependent Claim 61 words

A fluorine-free and zirconia-free glass having a linear absorption coefficient of at least 28 and substantially the following composition in weight percent: ______________________________________ Lead oxide 3% Barium oxide 21/4% Strontium 91/4% Na.sub.2 O 73/4% K.sub.2 O 81/4% Silica 64% Aluminum oxide 1% Calcium oxide 31/4% Magnesium oxide 1/4% Titanium oxide 1/2% Antimony oxide 1/2% Arsenic oxide 1/4% Cerium oxide 1/4% ______________________________________

References Cited (Backward Citations)

US2901366A Cited

US3258352A Cited

US3794502A Cited

US3464932A Cited

US4065697A Cited

JPS4814162B1 Cited

US4089693A Cited

GB1313243A Cited

US4065317A Cited

US3907584A Cited

US3805107A Cited

JPS5171314A Cited

US3987330A Cited

US4015966A Cited

US4174490A Cited

US4179638A Cited

US4277286A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1985-12-27	1986-06-28	1986-12-28	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1989-12-27	1990-06-28	1990-12-28	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1993-12-27	1994-06-28	1994-12-28	$7700.00	Window Closed / Lapsed

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