US2293989A - Manufacture of artificial wool - Google Patents

Description

Aug. 25, 1942. L L

MANUFACTURE OF ARTIFICIAL WOOL Filed July 24, 1959 mum llhlll Patented Aug. 25, 1942 MANUFACTURE OF ARTIFICIAL WOOL Anton Lely, Velp, Netherlands, assignor to American Enka Corporation, Enka, N. 0., a corporation of Delaware Application July 24, 1939, Serial No. 286,283 In Germany August 8, 1938 2 Claims.

The present invention relates to the manufacture of artificial wool-like fibers prepared from casein solutions and more particularly to the production of casein yarns that closely simulate the appearance of natural wool.

When comparing natural wool with so-called casein wool produced under standard conditions, it has been determined that the natural product, as distinguished from the synthetic yarn, has an inherent curl or crinkle which offers better felting properties and produces a more voluminous and fluffy yarn.

It has now been found that it is possible to impart to casein fibers a curl corresponding to that of natural wool. Such results have been eifected by rapidly stretching wet casein fibers and suddenly releasing the tension thereon. The thus treated fibers display a peculiar fine curl corresponding to that of merino wool.

It is, therefore, the object of the present invention to manufacture casein yarns that more closely resemble natural wool than any artificial product heretofore produced.

The invention further contemplates the provision of several methods for imparting a definite and accentuated curl or crinkle to casein fibers.

Another object of this invention involves the simultaneous production of a number of casein fibers associated to form a cable and its subsequent treatment to form a staple fiber having an improved curl or crinkle.

Essentially, this invention contemplates utilizing the inherent elasticity in fibers, slivers, cables and the like, prepared from casein solutions; and the process, broadly, consists of suddenly stretching the filaments or fibers, and then quickly re-.

leasing the tension. This step may be carried out during any of the manufacturing operations, but is preferably conducted after the fibers have been subjected to a hardening treatment, for example, with a formaldehyde solution. Regardless of the stage at which the stretch is applied, the fibers must be in a wet or moist condition.

In practicing the invention, the moist casein fibers are subjected to a sudden high tension so that they are stretched, for example, from 20% to 40%. Such stretching and immediate contraction may take place in any suitable apparatus, such as that shown in the single figure of drawing wherein the fibers l, after extrusion from spinneret 2 into a spin bath 3, are led through a formaldehyde hardening bath 3a and are stretched between two successive pairs of rollers d, ta and 5, 5a in which the distance D decreased periodically or non-periodically. Rollers I and 4a are mounted on shafts 6 and 6a which may be journaled in any suitable way, not shown. The said two rollers are caused to rotate in the direction indicated by the arrows by any conventional driving means, not shown. Rollers 5 and 5a are similarly provided with shafts i and la, respectively. Rollers 8 and 5 serve to drive belts B and 9 which in turn are passed around guide pulleys l0 and Ii, respectively. Belts 8 and 9, during their upper path of travel, provide a horizontal moving surface for continuously carrying the fibers I between the successive pairs of rollers. The distance D between pairs of rollers 4, la and 5, 5a is increased and decreased by operation of cam l2 driven by shaft l3 and acting through link It pivoted at l5 to a bar It connecting shafts 1, la and the similar shaft for pulley H and acting as a jour nal therefor. The entire roller assembly 5 and 5a is mounted for reciprocating movement in a table H. A cutter l8 operates in synchronism with the cam l2 whereby the fibers i may be cut at the point of greatest stretch. The supporting belts 8 and 9 are conventional as well as the driving cam arrangement.

It is also possible to guide and keep the cables taut through successive pairs of rollers which are maintained ata constant distance and use a hammer stroke arrangement for striking a section of the cable between the rollers at periodic or non-periodic intervals.

As indicated, if it is desired to produce staple fiber, the moist and suitable hardened bundle of fibers produced from the simultaneous extrusion and treatment of a collected cable are suddenly stretched and subjected to staple cutting while under tension. This has the same efiect as sudbetween these rollers is alternately increased or denly releasing the tension on a continuous section. Instead of staple cutting the cable, the yarns may be stretched until they are broken. In this method, by one continuous operation, the yarn bundles coming from the spinning machine are suitably hardened and torn off piece by piece while being stretched to provide staples with an improved curl.

The curl may also be produced on the finished casein yarns which have already been staple cut, carded and again worked into a ribbon-like or thread-dike product such as webs or slivers and thereafter moistened.

The following specific examples will serve to 11- lustrate several methods for carrying out the invention in its preferred form.

Example 1.-The freshly spun, washed, and

to 40% and suddenly relaxed; it is finally staple cut and dried.

Example 2.-'Ihe process is conducted in accordance with Example 1, except that while the cable is in a stretched condition, it is staple cut, the cutting operation having the same efiect as the sudden release of tension upon a continuous section oi the cable.

Example 3.The process is conducted in accordance with Example 1, except that the cable is stretched until it is broken piece by piece thereby providing the necessary stretching, relaxation and staple formation in a single continuous operation.

Example 4.--In applying the invention to a normally finished product, a carded sliver or web that has been produced from staple cut fibers, is moistened by immersion or spraying and the like. It is then suddenly stretched either continuously or intermittently, and quickly relaxed and finally dried under low tension.

It is understood, oi course, that variations may vention and various devices may be employed for that purpose without departing from the spirit oi the invention or the scope of the appended claims.

What is claimed is:

1. A process of curling casein fibers which comprises extruding a casein solution from a number of spinnerets to form a cable composed of several fibers, coagulating and hardening the cable in a formaldehyde solution, applying a sudden stretch and while undergoing said stretch, severing successive sections of the cable thereby forming accentuated curls therein.

2. A process of curling casein fibers which comprises extruding a casein solution from a number of spinnerets .to form a cable composed of several fibers, coagulating and hardening the cable in a formaldehyde solution, applying a sudden stretch suflicient to break the successive portions of the cable into staple lengths thereby to form curls therein.

ANTON LELY.

Images