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:
May. 12, 1987
Filed:
Oct. 17, 1985
Asahi Glass Company, Ltd., Tokyo, JP;
Abstract
A process for producing a porous glass which comprises forming a shaped product of borosilicate glass having a predetermined shape, heat-treating the shaped product for phase separation to form a silica rich insoluble phase and an alkali and boric oxide rich soluble phase, leaching out the soluble phase from the insoluble phase with an acid or an alkali to obtain a porous glass, wherein said shaped product of borosilicate glass is composed essentially of from 45 to 67% by weight of SiO.sub.2, from 0.5 to 10% by weight of Al.sub.2 O.sub.3, from 10 to 30% by weight of B.sub.2 O.sub.3, from 0.5 to 8% by weight of Na.sub.2 O, from 0.1 to 8% by weight of K.sub.2 O+Li.sub.2 O+Cs.sub.2 O, from 0.5 to 7% by weight of CaO, from 0.5 to 15% by weight of MgO+BaO+SrO, from 0 to 10% by weight of ZrO.sub.2 +TiO.sub.2 and from 0.03 to 3% by weight of F+SO.sub.3 +Cl+As.sub.2 O.sub.3 +Sb.sub.2 O.sub.3.