Patent GB-924087-A (GB)
Title: Improvements in or relating to fabrics other than garments
IPC: D01D5/253
Filed: 1959-07-13
Abstract: Fabrics other than garments comprise artificial fibres, having an essentially trilobal crosssection along their length, the cross-section having a tip radius ratio r1/R and an arm angle A (Figs. 1 and 2) within the range represented by the area LNP on Fig. 3, and a modification ratio M within the range represented by the area VUZ on Fig. 4.  M is defined as the ratio of the radius R to the radius R1 of a circle having centre c and inscribed within the cross-section.  Preferably, the artificial fibres are made of synthetic polymers, particularly polyesters, e.g. polyethylene terephthalate and a polyester containing a major proportion of terephthalate radicals and up to 2 mol. per cent of (5-sodium sulpho)-isophthalate radicals, polypropylene, and polyamides, e.g. polyhexamethylene adipamide. Other materials specified include polyhexamethylene sebacamide, polycaprolactam, polyxylylene azelaiamide, polyoctamethylene oxalamide, polyvinylpyrrolidone, polymetaphenylene isophthalamide, polymetaphenylene adipamide, copolyamides, and irradiation grafted polyamides, condensation products of ethylene glycol with a 90/10 mixture of terephthalic and isophthalic acids, polyesters derived from a 2,2-bis(4-hydroxyphenyl) propane and trans-p-hexahydroxylylene glycol with terephthalic acid; acrylonitrile polymers and copolymers, e.g. polyacrylonitrile, copolymers of acrylonitrile with vinyl pyridine, vinylidene chloride, vinyl chloride, or methyl acrylate; vinyl chloride and vinylidene chloride polymers and copolymers, polyurethanes, polyesteramides, polyethylenes, polycarbonates, e.g. those derived from 2,2-bis(4-hydroxyphenyl) propane, fluorinated polymers and copolymers, e.g. polymers of tetrafluoroethylene, hexafluoropropene, and monochlorotrifluoroethylene; composite filaments, e.g. a sheath of polyamides around a core of polyester or two acrylonitrile polymers differing in ionizable group content spun as a sheath and core; and regenerated cellulose, cellulose acetate, and other cellulose derivatives.  In examples, the fibres are made by melt spinning under specified conditions, using a spinneret each hole of which consists of three rectangular slots lying at 120 degrees to each other and joined at the centre, or the spinneret shown in Fig. XI of U.S.A.  Specification 2,945,739. The fibres and filaments may be crimped or uncrimped, drawn or undrawn, bulked or unbulked. Mixtures of the above fibres and blends containing a major proportion of them with a minor proportion of natural fibres may be used. Preferably, the tip radius ratio of the filaments r1/R and the arm angle A are within the ranges represented by the area QST in Fig. 3, when A is between 7 degrees and 60 degrees.  Such filaments have the greatest lustre highlight.  For pile fabrics. r1/R is desirably 0,22-0,37, M 1,75-2,6, and A between -17 degrees and 40 degrees.  For flat fabrics, r1/R is desirably 0,275-0,62, M 1,33-2,0, and A from 7 degrees to 74 degrees.  Specifications 578,079, 869,301, 905,895, U.S.A. Specification 2,828,528, French Specification 1,172,566 and Belgian Specification 549,179 also are referred to. <PICT:0924087/IV(a)/1> <PICT:0924087/IV(a)/2> <PICT:0924087/IV(a)/3> <PICT:0924087/IV(a)/4>