Abstract: The present invention relates to a chemically strengthened glass having a K-DOL defined as below of 5 ?m or less, and having a value CS50/(K-DOL×t) obtained by dividing a compressive stress CS50 (MPa) at a depth of 50 ?m from a surface of the chemically strengthened glass by a product of the K-DOL (?m) and a sheet thickness t (mm) of 45 (MPa/(?m·mm)) or more, K-DOL being a depth value (?m) from a glass surface of a compressive stress layer caused by K ions.

Abstract: Provided is an electrophotographic apparatus including: an electrophotographic photosensitive member; a voltage application unit configured to cause discharge from an electroconductive member to the electrophotographic photosensitive member; a charge transfer amount detection unit configured to detect a charge transfer amount per unit time resulting from the discharge from the electroconductive member to the electrophotographic photosensitive member; and a charging potential control unit, wherein V1 and V2 defined by specific procedures for the electrophotographic photosensitive member satisfy a relationship represented by the following expression (E-4): 100V1<V2?V1 (E-4), and wherein the charging potential control unit is configured to control the charging potential of the electrophotographic photosensitive member at the time of image formation.

Abstract: The present invention relate to a chemically strengthened glass manufacturing method for obtaining a chemically strengthened glass by performing an ion exchange treatment on a glass for chemical strengthening having a CTA value of x (MPa) obtained by Equation (1), the method including: a first ion exchange treatment of bringing a first molten salt composition into contact with the glass for chemical strengthening so that a CTave value, which is obtained by Equation (2), of the glass for chemical strengthening exceeds x (MPa); and a second ion exchange treatment, after the first ion exchange treatment, of bringing the glass for chemical strengthening into contact with a second molten salt composition having a component ratio different from a composition ratio of the first molten salt composition so that the CTave value of the glass for chemical strengthening is less than x (MPa).

Abstract: The present invention relates to a method for producing a chemically strengthened glass substrate, the method including the following steps (A) to (C): (A) preparing a chemically strengthened glass substrate A having a main surface and an end surface; (B) obtaining a glass substrate by polishing a surface of the chemically strengthened glass substrate A; and (C) performing ion exchange by bringing the glass substrate into contact with an inorganic salt composition including 90% by mass or more of KNO3 and 1.0% by mass or more and 6.0% by mass or less of NaNO3 to obtain a chemically strengthened glass substrate C.

Abstract: The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CSx [MPa,] at a depth x [µm] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CSx" of the stress value CSx in the profile satisfies the following expression within a range of CSx?0: 0<CSx"?0.050.

Abstract: The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CSx [MPa] at a depth x [?m] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CSx? of the stress value CSx in the profile satisfies the following expression within a range of CSx?0: 0<CSx??0.050.

Abstract: The present invention relates to a chemically strengthened glass having a thickness t (mm), in which a first-order derivative CSx? of a stress value CSx (MPa) is ?4.7 or larger in a range of CSx?0 in a profile of the stress value CSx (MPa), in which the stress value CSx (MPa) is a function of depth×(?m) from a glass surface, and in which the stress value CSx (MPa) is measured by a scattered light photoelastic stress meter, and a manufacturing method thereof.

Abstract: The present invention relates to a manufacturing method for a chemically strengthened glass, the method including: performing a first ion exchange by immersing a glass for chemical strengthening containing first alkali metal ions in a first molten salt composition containing second alkali metal ions; after the first ion exchange, performing a second ion exchange by immersing the chemically strengthened glass obtained after the first ion exchange in a second molten salt composition containing the first metal ions and third alkali metal ions; continuously using the first molten salt composition after being used for the first ion exchange; and continuously using a second molten salt composition after being used for the second ion exchange, in which: a concentration of the second molten salt composition is controlled by adding the first alkali metal ions to the second molten salt composition and a resulting second molten salt composition is used continuously.

Abstract: The present invention relates to a chemically strengthened glass having a thickness of t [mm], and having a profile of a stress value CSx [MPa] at a depth x [?m] from a surface of the glass, the stress value being measured by a scattered-light photoelastic stress meter, in which a second-order differential value CSx? of the stress value CSx in the profile satisfies the following expression within a range of CSx?0: 0<CSx??0.050.

Abstract: The present invention relates to a method for producing a chemically strengthened glass, the method including, performing a chemical strengthening treatment including the following steps (1) to (3) to a glass having a specific composition, (1) a step of bringing the glass into contact with an inorganic salt composition including 70 mass % or more of potassium nitrate to perform ion exchange; (2) a step of bringing the glass having been ion-exchanged in step (1) into contact with an inorganic salt composition including 50 mass % or more of sodium nitrate to perform ion exchange; and (3) a step of bringing the glass having been ion-exchanged in step (2) into contact with an inorganic salt composition including 70 mass % or more of potassium nitrate to perform ion exchange.

Abstract: The present invention relates to a method for producing a chemically strengthened glass, the method including, performing a chemical strengthening treatment including the following steps (1) to (3) to a glass having a specific composition, (1) a step of bringing the glass into contact with an inorganic salt composition including 70 mass % or more of potassium nitrate to perform ion exchange; (2) a step of bringing the glass having been ion-exchanged in step (1) into contact with an inorganic salt composition including 50 mass % or more of sodium nitrate to perform ion exchange; and (3) a step of bringing the glass having been ion-exchanged in step (2) into contact with an inorganic salt composition including 70 mass % or more of potassium nitrate to perform ion exchange.

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: The present invention relates to a method for producing a chemically strengthened glass, the method including, performing a chemical strengthening treatment including the following steps (1) to (3) to a glass having a specific composition, (1) a step of bringing the glass into contact with an inorganic salt composition including 70 mass % or more of potassium nitrate to perform ion exchange; (2) a step of bringing the glass having been ion-exchanged in step (1) into contact with an inorganic salt composition including 50 mass % or more of sodium nitrate to perform ion exchange; and (3) a step of bringing the glass having been ion-exchanged in step (2) into contact with an inorganic salt composition including 70 mass % or more of potassium nitrate to perform ion exchange.