Abstract: The present invention relates to a chemically strengthened glass satisfying A1 [MPa] of 600 or more, A2 [MPa] of 50 or more, B1 [?m] of 6 or less, B2 [?m] of 10% or more of t [?m], C [MPa] of ?30 or less, and A1/B1 [MPa/?m] of 100 or more when the chemically strengthened glass has a thickness t [?m] and a profile of a stress value [MPa] at a depth x [?m] from a glass surface is approximated by an error least-squares method in a region of 0<x<3t/8 using the following function while defining a compressive stress as positive and a tensile stress as negative: A1erfc(x/B1)+A2erfc(x/B2)+C, in which erfc is a complementary error function, and relations of A1>A2 and B1<B2 are satisfied.

Abstract: The present invention relates to a method for producing a chemically strengthened glass, the method including the following steps (1) to (3) in this order: (1) a glass sheet preparation step of preparing a glass sheet having, in a surface layer thereof, a compressive stress layer; (2) a first ion exchange step of bringing the glass sheet into contact with an inorganic salt composition to perform ion exchange of at least one pair of ions so as to decrease a compressive stress value of the compressive stress layer; and (3) a second ion exchange step of bringing the glass sheet into contact with an inorganic salt composition to perform ion exchange of at least one pair of ions so as to increase the compressive stress value of the compressive stress layer in the surface layer.

Abstract: A method for producing a chemically strengthened glass, including a step of bringing a glass containing sodium into contact with an inorganic salt containing potassium nitrate, thereby performing ion exchange of a Na ion in the glass with a K ion in the inorganic salt, in which the inorganic salt contains at least one salt selected from the group consisting of K2CO3, Na2CO3, KHCO3, NaHCO3, K3PO4, Na3PO4, K2SO4, Na2SO4, KOH and NaOH, and the method includes: a step of washing the glass after the ion exchange; a step of subjecting the glass to an acid treatment after the washing; and a step of subjecting the glass to an alkali treatment after the acid treatment.

Abstract: A chemically strengthened glass having a compressive stress layer formed in a surface layer thereof according to an ion exchange method, in which a surface of the glass has polishing flaws, the glass has a texture direction index (Stdi) of 0.30 or more, a hydrogen concentration Y in a region to a depth X from an outermost surface of the glass satisfies the following relational equation (I) at X=from 0.1 to 0.4 (?m), and a surface strength F (N) measured by a ball-on-ring test is (F?1400×t2) relative to a sheet thickness t (mm) of the glass: Y=aX+b??(I) in which meanings of respective symbols in the equation (I) are as follows: Y: hydrogen concentration (as H2O, mol/L), X: depth from the outermost surface of the glass (?m), a: ?0.300 or more, and b: 0.220 or less.

Abstract: A chemically strengthened glass having a compressive stress layer formed in a surface layer thereof according to an ion exchange method, in which the glass has a surface roughness (Ra) of 0.20 nm or higher, a hydrogen concentration Y in a region to a depth X from an outermost surface of the glass satisfies the following relational equation (I) at X=from 0.1 to 0.4 (?m), a surface strength F (N) measured by a ball-on-ring test under the following conditions is (F?1500×t2) relative to a sheet thickness t (mm) of the glass, and a surface of the glass has no polishing flaw: Y=aX+b??(I) in which meanings of respective symbols in the equation (I) are as follows: Y: hydrogen concentration (as H2O, mol/L); X: depth from the outermost surface of the glass (?m); a: ?0.270 to ?0.005; and b: 0.020 to 0.220.