Patent GB-852730-A (GB)
Title: Improvements in the treatment of cellulose triacetate fibres
Inventor: BULL GEORGE FREDERICK
IPC: D06M13/165
Filed: 1956-03-29
Abstract: The sticking temperature and safe ironing temperature of cellulose triacetate fibres are raised by subjecting the fibres to the combined action of heat at a temperature of at least 100 DEG C. and a swelling agent.  The swelling agent, which preferably has a boiling point of at least 190 DEG C., is preferably water-miscible to the extent of at least three parts in 100 parts of water by weight at 20 DEG C., e.g. gamma-butyrolactone, benzyl alcohol and acetamide. The fibres may be impregnated with the swelling agent by padding either directly or in an aqueous liquid.  If the swelling agent is not miscible with water in the proportion employed, a water-miscible liquid, e.g. methyl, ethyl, n-propyl or isopropyl alcohol, may be added in order to render the aqueous liquid homogeneous, and in order that the liquid may remain uniformly disposed on the impregnated fibres during subsequent p  manipulation, a small proportion of a thickener, e.g. 1-3% of water-soluble methyl cellulose, may be added.  The impregnated fibres may be subjected to steaming or to a simple heat treatment such as immersion in a hot inert liquid, e.g. hot mercury or a low-melting alloy such as Wood's metal.  The treatment facilities the subsequent dyeing of the fibres, e.g. with disperse dyes, provided that the material carries the swelling agent or has not been dried after washing with water until free of the swelling agent when it enters the dye-bath.  Specifications 758,442 and 852729 are referred to. The Provisional Specification describes the use as swelling agents of carboxylic esters and ether-carboxylic esters of polyhydric alcohols, and also refers to Specifications 448,816, 448,817, 448,917, 687,414, 719,853, 721,674, 726,900, 731,930, 748,772 and 845,752.ALSO:The dyeing of cellulose triacetate fibres, e.g. with disperse dyes, is facilitated by subjecting them to the combined action of heat at a temperature of at least 100 DEG C. and a swelling agent. The swelling agent, which preferably has a boiling point of at least 190 DEG C., is preferably water-miscible to the extent of at least three parts in 100 parts of water by weight at 20 DEG C., e.g. gamma-butyrolactone, benzyl alcohol and acetamide.  The fibres may be impregnated with the swelling agent by padding either directly or in an aqueous liquid. If the swelling agent is not miscible with water in the proportion employed, a water-miscible liquid, e.g. methyl, ethyl, n-propyl or isopropyl alcohol, may be added in order to render the aqueous liquid homogeneous, and in order that the liquid may remain uniformly disposed on the impregnated fibres during subsequent manipulation, a small proportion of a thickener, e.g. 1-3% of water-soluble methyl cellulose, may be added.  The impregnated fibres may be subjected to steaming or to a simple heat treatment such as immersion in a hot inert liquid, e.g. hot mercury or a low-melting alloy such as Wood's metal.  The treatment facilitates the subsequent dyeing of the fibres provided that the material carries the swelling agent or has not been dried after washing with water until free of the p  swelling agent when it enters the dye-bath.  Specifications 758,442 and 852,729 are referred to.  The Provisional Specification describes the use as swelling agents of carboxylic esters and ether-carboxylic esters of polyhydric alcohols, and refers also to Specifications 448,816, 448,817, 448,917, 687,414, 719,853, 721,674, 726,900, 731,930, 748,772 and 845,752.