Sheet glass and method for manufacturing sheet glass
AssigneeFurukawa Electric Co., Ltd.
InventorsToshihiro Nakamura, Sadayuki Toda, Hisashi Koaizawa
Life of this patent
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Abstract
A sheet glass that has a side surface with an average surface roughness equal to or less than 0.2 μm is provided. Furthermore, a method of manufacturing a sheet glass is provided that includes processing a base-material glass sheet to obtain a sheet glass that has a side surface with an average surface roughness equal to or less than 0.2 μm. Moreover, a method of manufacturing a sheet glass is provided that includes processing a base-material glass sheet so that an average surface roughness of a side surface becomes equal to or less than a predetermined value according to a section modulus of the sheet glass that is to be manufactured.
Claims6
A method of manufacturing a sheet glass having a predetermined thickness and a rectangular cross section from a base-material glass sheet having a rectangular cross section, the method comprising:
- selecting a breakage threshold angle for the sheet glass;
- establishing a correlation between a section modulus of the sheet glass and the breakage threshold angle of the sheet glass, the section modulus being calculated according to the following equation
- section modulus=h×d2/6
- with h being a width of the sheet glass and d being the thickness of the sheet glass, the section modulus of the sheet glass being 0.0011 to 0.0656;
- determining a thickness-reduction ratio for heat-drawing, the thickness-reduction ratio being the width of the sheet glass divided by a width of the base-material glass sheet multiplied by 100%, the thickness-reduction ratio being determined for an average surface roughness of a side surface of the sheet glass that is equal to or less than a predetermined value;
- and
- heat-drawing the base-material glass sheet including:
- heating the base-material glass sheet to soften the base-material glass sheet;
- and
- drawing the base-material glass sheet at the determined thickness-reduction ratio to obtain the sheet glass with the selected breakage threshold angle that includes the side surface with the average surface roughness equal to or less than 0.2 micrometer.
A method of manufacturing a sheet glass having a predetermined thickness and a rectangular cross section from a base-material glass sheet having a rectangular cross section, the method comprising:
- selecting a breakage threshold angle for the sheet glass;
- establishing a correlation between a section modulus of the sheet glass and the breakage threshold angle of the sheet glass, the section modulus being calculated according to the following equation
- section modulus=h×d2/6
- with h being a width of the sheet glass and d being the thickness of the sheet glass, the section modulus of the sheet glass being 0.0036 to 0.0147;
- determining a thickness-reduction ratio for heat-drawing, the thickness-reduction ratio being the width of the sheet glass divided by a width of the base-material glass sheet multiplied by 100%, the thickness-reduction ratio being determined for an average surface roughness of a side surface of the sheet glass that is equal to or less than a predetermined value;
- and
- heat-drawing the base-material glass sheet including:
- heating the base-material glass sheet to soften the base-material glass sheet;
- and
- drawing the base-material glass sheet at the determined thickness-reduction ratio to obtain the sheet glass with the selected breakage threshold angle that includes the side surface with the average surface roughness equal to or less than 0.2 micrometer.
Dependencies are inferred from the claim text.