Process for producing a glass for cathode ray tubes
AssigneeAsahi Glass Company, Limited
InventorsHajime Itoh, Rei Kitamura, Mitsuyoshi Sakai, Keito Sekine, Misao Okada
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Abstract
A process for producing a glass for cathode ray tubes, having a Sb2O3 content of from 0 to 0.19% as represented by mass percentage and containing H2O, which process comprises a step of melting a raw material in an atmosphere under a pressure of P0 to obtain a molten glass, and a step of vacuum degassing the molten glass in an atmosphere under a pressure PA which is lower than P0, wherein the pressure P of the molten glass is made to be at most (6.1 W+0.06) atm in the vacuum degassing step, wherein W is the content of said H2O as represented by mass percentage.
Claims25
A process for producing glass for cathode ray tubes, which comprises:
- increasing water content in a raw material;
- melting the raw material in an atmosphere under a pressure of P0 to obtain a molten glass;
- vacuum degassing the molten glass in an atmosphere under a pressure of PA, which is less than P0;
- wherein the pressure P of the molten glass is made to be at most (6.1 W+0.06) atm in the vacuum degassing step, and wherein W is the content of water in mass %;
- and
- wherein an obtained hardened glass has at most 0.1 bubbles/g.
A process for producing glass for cathode ray tubes, which comprises:
- melting a raw material in an atmosphere under a pressure of P0 to obtain a molten glass;
- increasing a water content in the molten glass;
- vacuum degassing the molten glass in an atmosphere under a pressure of PA, which is lower than P0;
- wherein the pressure P of the molten glass is made to be at most (6.1 W+0.06) atm in the vacuum degassing step, and wherein W is the content of water in mass %;
- and
- wherein an obtained hardened glass has at most 0.1 bubbles/g.
Dependencies are inferred from the claim text.