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:
Jun. 27, 1989
Filed:
Sep. 16, 1987
Isao Oda, Nagoya, JP;
NGK Insulators, Ltd., , JP;
Abstract
High strength porcelain having an unglazed bending strength of greater than 1,400 kg/cm.sup.2 and consisting essentially of 22-85% by weight of SiO.sub.2, 10-73% by weight of Al.sub.2 O.sub.3, and 1.5-6.5% by weight of K.sub.2 O and/or Na.sub.2 O. The porcelain has a total degree of crystallinity of more than 40% by weight, and a crystalline grain size of not greater than 20 .mu.m, and it is free from defects of larger than 40 .mu.m. The porcelain is produced by pulverizing a starting material mixture of quartz-feldspar-alumina system so that 85-95% by weight of particles thereof have a grain size of not greater than 10 .mu.m, calcining the mixture, adding clay-mineral material therein, pulverizing so that the clay-mineral-added mixture contains less than 85% by weight of particles with a grain size of not greater than 10 .mu.m, forming, drying, and firing at 1,100.degree.-1,400.degree. C.