Glass plate and method for manufacturing glass plate

Abstract

A method of manufacturing a glass sheet includes: an initial crack forming step of forming an initial crack on a mother glass sheet (MG); and a cleaving step of causing a crack (CR) to propagate in a direction along a preset cleaving line (CL) and in a thickness direction of the mother glass sheet (MG), the crack starting from the initial crack, through use of a thermal stress generated by heating of an irradiation region (SP) of laser light (L) and cooling of a cooling region (CP). The cleaving step includes heating a surface layer (SL) and an inner portion (IL) of the mother glass sheet (MG) with the laser light (L) in the irradiation region (SP) and setting a difference ΔT between a highest temperature in the irradiation region (SP) and a lowest temperature in the cooling region to 575° C. or more.

Dependencies are inferred from the claim text.