Process for comingling crimped yarn

Claim 2

Process for the treatment of multifilament yarn comprising advancing at constant velocity successive lengths of a crimped multifilament yarn at a tension, measured with the yarn static, between 0.002 and 0.015 gram per denier through a straight tubular passageway; contacting said yarn in said passageway with a stream of gas entering said passageway at an acute angle as measured between the line of flow of said stream of gas and the yarn exit segment of said tubular passageway, with the central axis along the line of flow of said entering stream of gas and the central axis of said tubular yarn passageway being substantially in the same plane; and causing at least 90 percent of the gas which contacts said yarn to flow countercurrent to the direction of yarn travel through the tubular passageway.

Claim 3

Process of claim 1 wherein said gas undergoes no change of volume greater than about five fold as said yarn enters into and flows through said tubular yarn passageway; wherein said tubular yarn passageway consists of two successive cylindrical segments, the segment first traversed by the yarn being of the greater diameter and being concentric with the second segment; wherein the gas used is air at a pressure in the incoming air stream between about 10 p.s.i.g. and about 25 p.s.i.g.; and wherein the air is introduced into the larger segment of the yarn passageway through a cylindrical gas passageway, the central axis of which lies in the same plane as the central axis of the yarn passageway within a deviation of not more than 2 percent based on the diameter of the larger segment of the yarn passageway, said gas passageway intersecting said larger segment of the yarn passageway near its junction with said smaller segment; and wherein said yarn is entered into said region of confinement at a speed between 150 and 1500 yards per minute, and removed from said region of confinement at a speed differing by not more than 4 percent from said entering speed, these yarn speeds being as measured by the peripheral velocity of the yarn feed rolls and the peripheral velocity of the yarn removal rolls respectively.

Claim 4

Process of claim 1 wherein the crimped multifilament yarn is overfed into said tubular passageway at a rate approximately 4 percent greater than removal therefrom.

Claim 5

Process of claim 3 wherein the stream of gas is at a pressure between about 10 and 25 p.s.i.g. and the central axis of the yarn passageway within a deviation of not more than 10 percent.