| 摘要 |
<p>This invention relates to a method of finishing heat-reinforced plate glass and edge regions thereof having received heat reinforcing treatment over entire surfaces thereof. Conventionally, in order to be usable for fire doors or fire windows, it is necessary to carry out heat reinforcing treatment by heating plate glass in the temperature range (about 760 DEG C) far exceeding the softening point of glass, and blowing cooling air under the very high back pressure of 950mmAq to a continuous air cooled portion. This heat reinforcing treatment results in a loss of flatness of glass surfaces and warping to impair image reflection. In this invention, end surfaces (3a) of plate glass (3) are formed flat and finished with a maximum surface ruggedness not exceeding 0.05mm, and boundaries (3c) between end surfaces (3a) and front and back surfaces (3b) of the plate glass (3) are finished with a maximum surface ruggedness not exceeding 0.007mm. Thus, though the plate glass is treated with heat reinforcement by the method simpler and more convenient than the prior art, the plate glass maintains performance as fire glass. It is now possible to provide quality improvement as plate glass, a reduction in running cost of heat reinforcing treatment equipment, and a reduction in working stress due to the weight of the plate glass itself in time of fitting the plate glass. <IMAGE></p> |
