Glass substrate manufacturing method and glass thereof

Abstract

A glass of the present invention includes a first layer having a porous structure of nanoscale pores which are etched by an etchant that is a substitute for hydrofluoric acid (HF) or fluoride such that HF or fluoride is not used as the etchant, and a second layer which is not etched by the etchant. The glass is effectively applied to various applications requiring high light transmission such as a protective filter for a display device, a solar cell, a mobile communication device, glass of a building structure, and an optical element lens.

1 . A glass comprising:
 a first glass layer having a porous structure of nanoscale pores in a thickness direction of the glass, the first glass layer being formed by etching a surface of the glass with an alkali solution etchant, and the etchant being a substitute for hydrofluoric acid (HF) or fluoride such that HF or fluoride is not used as the etchant, and   a second glass layer which is not etched by the etchant,   wherein the porous structure is formed only by cleaning the surface of the glass and etching the cleaned surface of the glass with the alkali solution etchant, the etching not requiring any other addition processes, and   wherein the porous structure is formed on the cleaned surface of the glass without forming a separate coating layer on the surface of the glass.   
     
     
         2 . The glass according to  claim 1 , wherein a depth of the first glass layer in a thickness direction of the glass substrate is smaller than a wavelength of incident light. 
     
     
         3 . The glass according to  claim 2 , wherein the depth of the first glass layer is ¼ or less of the wavelength of the incident light. 
     
     
         4 . The glass according to  claim 1 , wherein the first glass layer imparts the glass with at least one property selected from among an antireflection property, a hydrophilic property and an antifogging property. 
     
     
         5 . The glass according to  claim 1 , wherein the first glass layer has a refractive index value that continuously varies between a refractive index of air and a refractive index of the glass. 
     
     
         6 . The glass according to  claim 1 , wherein the glass is a soda-lime glass, an aluminosilicate glass or a glass for liquid crystal display (LCD). 
     
     
         7 . The glass according to  claim 1 , wherein as the alkali solution, potassium hydroxide (KOH), sodium hydroxide (NaOH) or lithium hydroxide (LiOH) is used. 
     
     
         8 . The glass according to  claim 1 , wherein the glass substrate is used as a glass substrate of a photovoltaic cell, a glass substrate of a protective filter for a display device, a glass substrate of a mobile communication terminal, a glass substrate of a rearview mirror, a glass substrate for an optical device or a glass substrate for a building. 
     
     
         9 . The glass according to  claim 1 , wherein the porous structure is formed by immersing the glass in the alkali solution etchant at a temperature of less than 100° C. and etching the cleaned surface of the glass with the alkali solution etchant for 4 hours or less than 4 hours. 
     
     
         10 . The glass according to  claim 9 , wherein the porous structure is formed without any separate heat treatment. 
     
     
         11 . The glass according to  claim 9 , wherein the etching in the alkali solution etchant is carried out at a temperature below 100°. 
     
     
         12 . The glass according to  claim 1 , wherein the glass is cleaned before the etching, by piranha cleaning using sulphuric acid and hydrogen peroxide at a ratio of 3:1.