| 摘要 |
<p>1359165 Glass laminates GLAVERBEL 21 May 1971 16282/71 Heading B5N [Also in Division C1] A plurality of sheets, including at least one glass sheet, are secured together by a frame and/ or by an intervening organic sheet in facing relationship and one glass sheet is subjected over at least part of its area to a rectifying treatment which improves the face of such sheet by reducing the impairment of that face by faults liable to cause stress concentrations when tensioning forces are applied thereto, the sh eets being secured together so that at least the improved face is located internally. The rectifying treatment may be a fine-polishing treatment, a chemical dissolution, as by a medium containing fluorine ions, of a surface layer having a thickness at least equal to the deepest fault present. The glass sheet or sheets may also have treatment such as thermal or chemical, ion-diffusion, tempering to give compressive stresses in the faces of the sheets; or may be stressed by assembling the sheets so that at least the one sheet is held in a state of elastic flexure, and the sheets may have differing resistances to breakage by flexure. The differing resistances may be achieved by selecting sheets of different thickness and/or by chemical tempering. The sheets may be flat or curved and may, as shown, have differing curvatures, which are secured together with or without an intervening plastics sheet, as 14, 15, 16 or 21, 22 and be held at a further different curvature in a frame (17, not shown) or 23. Specifications 1,274,731; 1,359,168; 1,359,169 and 1,359,170 are referred to.</p> |
