| 摘要 |
Dry-spun protein fibres, particularly fibres dry spun from caseinate solutions, are hardened in an atmosphere containing a gaseous hardening agent, e.g. an aldehyde or ketone, the atmosphere being from one-third to two-thirds saturated with water vapour. Such an atmosphere may arise from a mixture of water, formaldehyde and sodium chloride, or a saturated solution of formaldehyde in the presence of fused calcium chloride. Gaseous hardening agents which may be employed are formaldehyde, acetaldehyde and quinone, and the hardening treatment is effected at room temperature. After hardening, the fibres are treated with dilute acid to free them from basic substances employed in the spinning solution. Examples are given in which fibres dry-spun from sodium caseinate solution are suspended in a closed chamber for several days and subjected at room temperature to the vapours arising from an aqueous solution of formaldehyde saturated with sodium chloride or an aqueous formaldehyde solution containing fused calcium chloride. The hardened fibres are subsequently treated with acid, washed and dried. |
