| 摘要 |
466,064. Preparing tanned fibres. FREUDENBERG GES., C. May 12, 1936, No. 13462. Convention date, May 20, 1935. [Class 76] [Also in Group IX] A process for the preparation of absorbable wadding, particularly for surgical purposes, is characterized in that animal hides or sinews are first subjected to a swelling treatment, e.g. in milk of lime, sulphurous acid solution &c., or a thermal loosening treatment, the swollen or loosened material being then subjected to a mechanical coarse shredding operation in crushing - rollers, hollanders, &c., such that the individual fibres are preserved ; the resulting coarse fibrous mass being thereafter subjected to a waterdisplacing treatment with organic liquids miscible with water, particularly acetone or 60 per cent to 100 per cent alcohol, regulated in accordance with the required degree of softness of the finished wadding, the material so treated being then finely shredded or teased out by treatment with carding combs, &c., so as to liberate the individual fibres. The starting materials may be subjected to partial hydrolytic decomposition under the action of heat simultaneously with or prior to the swelling treatment. The treatment with organic liquids may be effected in stages, the material being preferably freed from the main aqueous liquids by draining, expressing, centrifuging, &c. Formaldehyde &c. may be used to tan slightly the wadding during or after its preparation. Treatment with hot alcohol or alcohol containing iodine or Rioanol may be employed at the last immersion to sterilize the fibres. Specification 446,533 is referred to.
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