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:
Jul. 11, 1978
Filed:
Oct. 20, 1977
Roger F Bartholomew, Painted Post, NY (US);
Che-Kuang Wu, Horseheads, NY (US);
Corning Glass Works, Corning, NY (US);
Abstract
The present invention is directed to the preparation of hydrated glasses in the Na.sub.2 O-K.sub.2 O-PbO-SiO.sub.2 base composition system containing an amount of BaO and/or Y.sub.2 O.sub.3 and/or ZnO and/or ZrO.sub.2 effective to cause the hydrated glass to be essentially colorless. Such glasses are transparent, exhibit refractive indices higher than 1.60, and which demonstrate intrinsic thermoplastic properties thereby enabling such to be readily molded into optical quality components at relatively low temperatures. The operable glasses in the anhydrous state consist essentially, in mole percent on the oxide basis, of 8-18% Na.sub.2 O, 2-6% K.sub.2 O, 10-23% Na.sub.2 O + K.sub.2 O, >15 but <21% PbO, 55-67% SiO.sub.2, the mole ratio PbO:SiO.sub.2 being between 0.225-0.3, and an effective amount of BaO and/or Y.sub.2 O.sub.3 and/or ZnO and/or ZrO.sub.2 up to the indicated maxima of 5% BaO, 5% Y.sub.2 O.sub.3, 8% ZnO, and 5% ZrO.sub.2, BaO + Y.sub.2 O.sub.3 + ZnO + ZrO.sub.2 not exceeding 10%.