The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 04, 1997
Filed:
Aug. 30, 1995
Eckhart Watzke, Jena, DE;
Andrea Kampfer, Jena, DE;
Thomas Kloss, Jena, DE;
Gerhard Kemmler, Jena, DE;
Jenaer Glaswerck GmbH, Jena, DE;
Abstract
Borosilicate glass weak in boric acid having a high chemical stability with an alkali resistance according to DIN 52 322 of LBK-Class 1, a thermal expansion .alpha..sub.20/300 between 4.0 to 5.3.times.10.sup.-6 K.sup.-1, a ratio .alpha.'/.alpha. of thermal expansion coefficients above T.sub.g (.alpha.') to below T.sub.g (.alpha.) of 4 to 8, a glass transformation temperature between 500.degree. C. and 600.degree. C., high radiation transmittance and a UV transmission .tau..sub.250 nm/1 mm of 0 to 70% or .tau..sub.300 nm/1 mm of 0 to 91% of the composition in percent by weight on oxide basis of: SiO.sub.2 >75; B.sub.2 O.sub.3 1 to <9; Al.sub.2 O.sub.3 3 to 6; Li.sub.2 O 0 to 4; Na.sub.2 O 0 to 8; K.sub.2 O 0 to 6; MgO 0 to 3; CaO 0 to 3; BaO 0 to 2; SrO 0 to 2; ZnO 0 to 3; ZrO.sub.2 0 to 3; SnO.sub.2 0 to 3; SnO 0 to 3; TiO.sub.2 0 to 2; CeO.sub.2 0 to 2; Fe.sub.2 O.sub.3 0 to 1; with SiO.sub.2 +B.sub.2 O.sub.3 >83; SiO.sub.2 :B.sub.2 O.sub.3 >8; SiO.sub.2 +Al.sub.2 O.sub.3 +ZrO.sub.2 >83; Li.sub.2 O+Na.sub.2 O+K.sub.2 O 5 to 10; MgO+CaO+BaO+SrO+ZnO>3.