GB1167109A - Method for the Production of Bicomponent Filaments or Fibres. - Google Patents

Abstract

1,167,109. Conjugate filaments. CHEMIEFASER LENZING A.G. 1 Feb., 1968 [3 Feb., 1967], No. 5279/68. Heading B5B. Bicomponent filaments or fibres having a high mechanical crimping stability are made by jointly spinning two different thermoplastic fibre-forming synthetic materials through the same spinning nozzles and subsequently drawing, and if desired, setting the filaments, wherein one component consists of a polyester, a polyamide, a polyesteramide, or a blend of a polyester and a polyamide having a polyamide content of 5 to 20% by weight, and the other component consists of a polyesteramide or a blend of a polyester and a polyamide containing 5 to 20% by weight of the structural units prevailing in the first component. Mechanical crimping stability is defined as the ratio between the degree of crimping after exerting stress on the filament and the degree of crimping prior to stressing, expressed as a percentage. Setting the drawn filaments may be effected by heat treatment with hot air or wet steam, or exposure to media effecting setting, e.g. methylene chloride. The two components are preferably supplied at a proportion of 50: 50% by weight; the proportion of the polyamide may, however, be varied from 20: 80% by weight. Preferred polyamides are polyhexamethylene diamine adipate, polycaprolactam, polyamino undecylate or polyamino dodecylate; preferred polyesters include polyethylene terephthalate, polyethylene terephthalate / isophthalate copolyester or polypara-dimethylol cyclohexyl terephthalate; and combinations of the structural units of the above-mentioned polyamides or polyesters are used as polyester-amides. Spinning is effected in known manner, using a spinneret suitable for the production of conjugate filaments, and the filaments are drawn and set. A predetermined stress may be applied during setting of the filaments, in order to obtain a predetermined crimping value. In Example 1, the first component is polyethylene terephthalate and the second component is a polyesteramide consisting of 90% by weight of polyhexamethylene diamine adipate and 10% by weight of polyethylene terephthalate. After melt-spinning to produce side-by-side conjugate filaments drawing is effected using a heated snubbing pin at 75‹ C. and an arcuate heater at 160‹ C. Draw ratios of 1: 4 to 1: 5 are used. Setting is effected in wet steam at 130‹ C. In Example 2, component 1 is polycaprolactam and component 2 is a polyesteramide consisting of 90% polyethylene terephthalate and 10% polycaprolactam. Example 3 gives a further polymer combination. Drawing and heat setting are effected as in Example 1.