초록 ▼

This invention relates to a process for the production of an optical glass article, which comprises neutralizing an aqueous solution containing silicic acid to form a porous gelled body, removing soluble materials from the porous gelled body to form a porous glass body, stuffing the porous glass bod

This invention relates to a process for the production of an optical glass article, which comprises neutralizing an aqueous solution containing silicic acid to form a porous gelled body, removing soluble materials from the porous gelled body to form a porous glass body, stuffing the porous glass body with a solution containing at least one compound capable of being converted into an oxide dopant for changing the refractive index of the glass body, selected from the group consisting of CsNO3, RbNO3 and TlNO3, unstuffing the glass body with a solvent or solution having a suitable composition at a suitable temperature to leach the compound out of the outside glass body and to give a predetermined concentration distribution in the micropores of the glass body, optionally immersing the unstuffed body in an organic solvent, precipitating the compound in the micropores, drying the glass body in a predetermined atmosphere to decompose the compound, further heating at a higher temperature, and then firing at a temperature sufficiently high to completely decompose the compound and to completely burn the organic materials, but lower than the melting point of silica.

대표청구항 ▼

A process for producing an optical glass article, which comprises preparing at least two solutions having a pH of 10 to 15 and an SiO2 content of about 1 to 12 mols/l and containing at least one silicate selected from the group consisting of lithium polysilicate, sodium silicate, potassium silicate,

A process for producing an optical glass article, which comprises preparing at least two solutions having a pH of 10 to 15 and an SiO2 content of about 1 to 12 mols/l and containing at least one silicate selected from the group consisting of lithium polysilicate, sodium silicate, potassium silicate, rubidium silicate, cesium silicate, thallium silicate, quaternary ammonium silicate and colloidal silica, combining these solutions to form a mixed solution, reacting the mixed solution with at least one organic compound selected from the group consisting of formaldehyde, paraformaldehyde, formamide, glyoxal, methyl formate, ethyl formate, methyl acetate and ethyl acetate at a temperature from the freezing point to the boiling point of the reaction solution in a time sufficient to polymerize silica and form a porous gelled body, leaching the porous gelled body with a leaching solution selected from the group consisting of water, an aqueous solution of an inorganic acid and an aqueous solution of an organic material, capable of dissolving residues in the porous gelled body, until the leaching reaches the central part of the porous gelled body, to form a porous glass body having micropores therein, stuffing the porous glass body with a solution containing at least one compound capable of being converted into an oxide dopant for changing the refractive index of the porous glass body, selected from the group consisting of CsNO3, RbNO3 and TlNO3, unstuffing the porous glass body with a solvent or solution having a suitable composition at a suitable temperature to leach the compound out of the porous glass body so as to give a predetermined concentration distribution of the compound in the micropores, precipitating the compound in the micropores, drying the glass body in a predetermined atmosphere to decompose the compound, further heating the glass body at a higher temperature, and firing the glass body at a temperature sufficiently high to completely decompose the compound and to completely burn any organic materials in the glass body, but lower than the melting point of silica.