| 摘要 |
<p>Appearance of bitumenised felts and similar facing material is improved by coating external surface with layer of coloured mineral granules. Quartz, Schist or other rock is crushed to angular particles sized to 0.5-1.6 mm mixed with Fe, Cr, Ti or Co oxide pigment of particle size 10 mu m, 1,5-5% pref. 2-3% pigment is added and 5-8% of an alkali metal silicate soln. followed by mixing in a mechanical mixer, firing in a furnace at 450-650 degrees C. to fuse enamel and produce waterproof coloured stones. Product adds to appearance, rigidity and stability of exposed flexible building materials when bonded to surface.</p> |
