US 11,927,882 B2
Quartz glass plate
Tatsuya Mori, Koriyama (JP); Akira Sato, Koriyama (JP); Atsushi Shimada, Sasebo (JP); Yuya Yokosawa, Koriyama (JP); and Nobumasa Yoshida, Koriyama (JP)
Assigned to SHIN-ETSU QUARTZ PRODUCTS CO., LTD., Tokyo (JP)
Appl. No. 17/046,202
Filed by SHIN-ETSU QUARTZ PRODUCTS CO., LTD., Tokyo (JP)
PCT Filed Mar. 25, 2019, PCT No. PCT/JP2019/012454
§ 371(c)(1), (2) Date Oct. 8, 2020,
PCT Pub. No. WO2019/202921, PCT Pub. Date Oct. 24, 2019.
Claims priority of application No. 2018-080176 (JP), filed on Apr. 18, 2018.
Prior Publication US 2021/0173299 A1, Jun. 10, 2021
Int. Cl. G03F 1/64 (2012.01); C03B 20/00 (2006.01); C03C 3/06 (2006.01); C03C 4/00 (2006.01); C03C 8/24 (2006.01); C03C 27/10 (2006.01)
CPC G03F 1/64 (2013.01) [C03B 20/00 (2013.01); C03C 3/06 (2013.01); C03C 4/0085 (2013.01); C03C 8/24 (2013.01); C03C 27/10 (2013.01); C03C 2201/02 (2013.01)] 11 Claims
OG exemplary drawing
 
1. A quartz glass plate having
a quartz glass plate body and
a quartz glass member adhered to the quartz glass plate body through an adhesive layer, wherein
the adhesive layer comprises silica,
a sum of concentrations of Li, Na, and K ions, being alkali metal ions and Ca ions, being alkaline earth metal ions contained in the adhesive layer is 10 ppm by mass or less, and
the adhesive layer has a density of 1.0 g/cm3 or more and 2.0 g/cm3 or less.