| 摘要 |
Fancy yarns are made by subjecting yarns of a synthetic thermoplastic material, especially polyester yarns, to partial stretching, e.g. by a factor of 1.5-3.5, in contact with an aqueous lower alkanol or other crack-producing agent, followed by a heat relaxation treatment, the said or other heat treatment, or a supplementary stretch, being applied intermittently or to a continuously varying degree. The yarns obtained have a flake appearance and comprise alternating thick and thin portions, the diameters of the thick and thin portions both varying macroscopically, and the thick parts varying in diameter on the microscopic scale, the zones of smallest diameter corresponding to zones of highest crystallinity and orientation. The thin parts may vary in diameter microscopically in an analogous way but with smaller variations, or may be substantially uniform. |
