| 摘要 |
<p>1387221 Coated glass ALLEGHENY LUDLUM INDUSTRIES INC 22 March 1973 [23 March 1972] 13984/73 Addition to 1298410 Heading B2E A method of providing a transparent, water insoluble layer on glass comprises coating the glass with a solution containing Mg<SP>++</SP>, NH 4 <SP>+</SP>, chromate and phosphate ions, and curing the layer (e.g. by heating to at least 400‹C) to render it water insoluble. The layer then comprises Mg<SP>++</SP> cations and anionic polymeric chains containing Cr, O and P atoms. In solution, the phosphate ion spacers may be H 3 PO 4 , H 2 PO 4 -, HPO 4 = or PO 4 # or polymeric oxyacid ionions and the chromate may be CrO 4 =, Cr 2 O 7 = &c. The Mg<SP>++</SP> ions may be supplied as oxide, hydroxide, carbonate, bicarbonate, phosphate or chromate; ammonium ions as ammonia (solvated), or hydroxide, carbonate or bicarbonate; phosphate ions as o-phosphoric acid, Mg 3 (PO 4 ) 2 , (NH 4 ) 3 (PO 4 ) 2 or magnesium ammonium phosphate; and chromate as CrO 3 or chromate or dichromate of magnesium or ammonium. The solution is preferably aqueous and may contain wetting agents or pigments or dyes to render the transparent protective layer coloured.</p> |
