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. 20, 2021
Filed:
Oct. 16, 2018
Agc Inc., Chiyoda-ku, JP;
Hirofumi Tokunaga, Chiyoda-ku, JP;
Kazutaka Ono, Chiyoda-ku, JP;
AGC Inc., Chiyoda-ku, JP;
Abstract
To provide an alkali-free glass having a high specific elastic modulus, a suitable strain point, a low density, a not too low thermal expansion coefficient, a good clarity and a good solubility. An alkali-free glass, which comprises, as represented by mol % based on oxides, SiO: 62 to 70%, AlO: 11 to 14%, BO: 3 to 6%, MgO: 7 to 10%, CaO: 3 to 9%, SrO: 1 to 5% and BaO: 0 to 1%, wherein [SiO]+0.7[AlO]+1.2[BO]+0.5[MgO]+0.4[CaO]−0.25[SrO]−0.88[BaO] is at least 85, [SiO]+0.45[AlO]+0.21[BO]−0.042[MgO]+0.042[CaO]+0.15[SrO]+0.38[BaO] is from 72 to 75, 0.4[SiO]+0.4[AlO]+0.25[BO]−0.7[MgO]−0.88[CaO]−1.4[SrO]−1.7[BaO] is at most 19, the specific modulus is at least 32 MN·m/kg, the strain point is from 690 to 710° C., the density is at most 2.54 g/cm, the average thermal expansion coefficient at from 50 to 350° C. is at least 35×10/° C., and the temperature Tat which the glass viscosity reaches 10dPa·s is from 1,610 to 1,680° C.