| 摘要 |
<p>555,480. Lubricating compositions. AMERICAN VISCOSE CORPORATION. Dec. 9, 1941, No. 15854. Convention date, July 1. [Class 91] [Also in Groups IV and V] A twisted yarn is impregnated with a substantially non-aqueous solution comprising an ester of an anhydropolyhydric alcohol with a saturated fatty acid having at least 10 carbon atoms and the ester is caused to solidify on the yarn and thus set the twist. The twist-set yarn is formed into a fabric, and the ester is then removed. The ester used is of a firm unctuous, soapy or waxy nature, and is of such a low melting point that it is readily fused superficially by friction to provide effective lubrication of the yarn as it passes through weaving, knitting, or other machines, and yet it does not give such a low coefficient of friction as to permit excessive slippage of the yarn. The ester may subsequently be removed from the fabric by a mild aqueous scouring bath. An ester of glycide, sorbitan, mannitan, dulcitan, mannide, or sorbide, or of an anhydro derivative of a pentol, hexane pentol, arabitol, or erythritol, with myristic, palmitic, or stearic acid may be used. A mixture of such esters may be used. Mannide dipalmitate is obtained by heating mannitol with two molecular equivalents of palmitic acid in 'presence of phosphoric acid at 200-240‹C. or above for several hours. A mixed ester may be used, e.g. mannide myristate palmitate. Esters in which all the hydroxyl groups of the anhydro polyhydric alcohol are esterified may be used. The twisted yarn may be impregnated with the ester while it is in the form of a wound package on a bobbin or other carrier. In an example, the yarn package is dipped into a solution of mannide dipalmitate in Stoddard solvent ( a petroleum hydrocarbon fraction of boiling range 150‹- 210‹C.). After centrifuging, the volatile solvent is evaporated from the yarn package at a slow rate. The package may be stored in an atmosphere containing the vapour of the volatile solvent. Knitting or weaving may be carried out in an atmosphere of high humidity or the yarn may be steamed or stored in a moist atmosphere prior to the knitting or weaving operation. The ester may be removed from the fabric by a hot aqueous scouring liquid or by treatment with a non-aqueous volatile solvent. The treatment may be applied to cotton, wool, silk, regenerated cellulose, cellulose acetate, and other yarns. Instead of applying the ester solution 'by dipping the yarn package in the liquid, the solution may. be applied to the travelling yarn by spraying or by means of moistened rollers.</p> |
