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:
Aug. 31, 2021
Filed:
Apr. 10, 2018
Ohara Inc., Kanagawa, JP;
OHARA INC., Kanagawa, JP;
Abstract
To provide a crystallized glass substrate that is hard and resistant to fracture and that is also resistant to shattering upon breakage. A crystallized glass substrate includes a crystallized glass serving as a base material and a compressive stress layer forming a surface thereof. The crystallized glass contains, in % by weight on an oxide basis, 40.0% to 70.0% of a SiOcomponent, 11.0% to 25.0% of an AlOcomponent, 5.0% to 19.0% of a NaO component, 0% to 9.0% of a KO component, 1.0% to 18.0% of one or more selected from a MgO component and a ZnO component, 0% to 3.0% of a CaO component, and 0.5% to 12.0% of a TiOcomponent. The SiOcomponent, the AlOcomponent, the NaO component, the one or more selected from the MgO component and the ZnO component, and the TiOcomponent are present in a total amount of 90% or more. The compressive stress layer has a depth of layer of 40 μm or more. The compressive stress layer has a surface compressive stress of 750 MPa or more. The compressive stress layer has a central tension of 65 MPa or less as determined by curve analysis.