Title:
TEMPERED GLASS
Document Type and Number:
Japanese Patent JP3968761
Kind Code:
B2
Abstract:
PROBLEM TO BE SOLVED: To suppress the occurrence of cracks which are the cause for breakage and to enhance end part strength by grinding only the ridge parts at both end faces of the end faces of a cut plate to form the polished ridge part surfaces inclined with a front surface and the end faces, specifying the max. value, of the surface ruggedness on the polished ridge part surfaces and executing a heat treatment.
SOLUTION: The end faces of the glass plate are held as cut and are not ground. The max. value of the surface ruggedness of the polished ridge part surface is specified to ≤0.003 mm. As a result, the surface compressive stress in the part to 50 mm from the end faces on the surface is made to ≥1,500 kgf/cm2 by a thermal tempering treatment to attain the surface compressive stress of about 1,500 kgf/cm2, by which the exhibition of the performance as fireproof glass is made possible, the execution of the heat heatment at ≤650°C is made possible and good appearance quality is obtd. Further preferably, the angle formed by the polished ridge part surface and the end faces of the glass plate is specified to 120 to 150° and the projection width of the polished ridge part surface to the front end face of the glass is specified to ≥1 mm.
Inventors:
Tsuyoshi Tanaka
Yukifumi Oketani
Takahiro Murakami
Kakihara Arata
Masashi Yamamoto
Yukifumi Oketani
Takahiro Murakami
Kakihara Arata
Masashi Yamamoto
Application Number:
JP24088197A
Publication Date:
August 29, 2007
Filing Date:
September 05, 1997
Export Citation:
Assignee:
Asahi Glass Co., Ltd.
International Classes:
C03B27/00; C03B33/02; (IPC1-7): C03B27/00; C03B33/02
Domestic Patent References:
| JP9208246A | ||||
| JP55047232A | ||||
| JP9071429A |
Attorney, Agent or Firm:
Kenzo Matsuura