| 摘要 |
A yarn is made by piercing a strip of filament-forming material, e.g. nylon, polyethylene terephthalate, polypropylene, cellulose di-acetate, with holes or slits, drawing, e.g. with a ratio of 4-20, the strip (whilst heated,, if of thermoplastic material), cutting or breaking a proportion of the filamentary structures thereby formed in the strip, and twisting the resultant material. Prior to the twisting, the strip may be heated under minimum tension to cause the "filaments" to crimp randomly. The manufacture may be continuous, in one or more machines, or discontinuous with wind-up at intermediate stages. Some broken ends project from the surface of the yarn to impart a soft "handle" thereto and inwardly projecting ends are trapped between continuous filamentary structures and thereby impart bulk to the yarn. The strip may be pierced by means of rotating knives, needle combs or bombardment with high-velocity particles, e.g. of glass or metal, which may be heated. The cutting or breaking may be effected by continuous or interrupted blasts of air or jets of airborne particles, e.g. sand or glass or metal balls, (which may be heated) or by abrasion.
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