| 摘要 |
<p>1,142,838. Fibre and perlite composition. JOHNS-MANVILLE CORP. 21 Nov., 1966 [22 Dec., 1965], No. 51962/66. Headings C3C and C3N. [Also in Division D2] A heat insulating board comprises by weight 40 to 75% expanded perlite particles, 15 to 55% fibres, 3 to 10% bituminous material and 0À3 to 5% starch. The fibres may be cellulosic such as newsprint fibres, or a mixture of cellulosic and mineral fibres, optionally in the proportions 15 to 25% of the total boards solids of cellulosic fibres, 10 to 30% mineral fibres and 0.5 to 5% asbestos fibres. The bituminous material may be asphalt. The strength of the board is high and its resistance to fire and water absorption maintained. The starch may be in the form of raw tapioca starch grains, included with the other solids in an aqueous slurry which is pressed and dried, the tapioca grains cooking in the drier to form a gel-like cooked starch material, which functions as a binder. Small amounts of clay, up to 5%, may be included.</p> |
