| 摘要 |
<p>531,446. Keratin ; moulding powders. BAKONYI, S. July 22, 1939, No. 21368. Convention date, Aug. 26, 1938. [Class 2 (iii)] Keratin-containing material is refined to make it suitable for incorporation in ureaformaldehyde or thiourea-formaldehyde moulding powders by treatment first with an oxidizing agent and then with a reducing agent, with or without a preliminary and/or final treatment with dilute acid. In an example meal or chips of hoofs or horn are treated with 1-2 per cent hydrochloric acid at 30-36‹C. for 12-24 hours, washed, treated with 1 per cent weakly alkaline hydrogen peroxide at 30-36‹C. for 12-48 hours, washed, treated with 0.8-1 per cent sodium hydrosulphite for 12-24 hours, washed, treated with 0.1-1 per cent formic acid and finally washed, dried and ground. A resin mix of urea (or urea and thiourea) formalin, ammonia (to neutralize) and ethylene diamine, to which may be added more urea or thiourea. to bring the ratio to formaldehyde to 1:1.75, is (1) mixed and kneaded with the refined keratin flour, the mass being extruded into rods which are dried and ground; or (2) mixed also with condensation products of formaldehyde and phenol or cresol and with hexamethylene tetramine ; or (3) the amount of keratin used in the first example may be increased but with addition of water. The Specification as open to inspection under Sect. 91 states that zinc chloride may be added to the acid for the treatment of the keratin, and that in example 1, to the condensation mixture before adding the keratin, there may be added phthalic anhydride or monoglyceride or adipic acid or monoglyceride in alcoholic solution. This subject-matter does not appear in the Specification as accepted.</p> |
