JPS5933688B2 - Manufacturing method of composite bulky yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for manufacturing a composite bulky yarn, and more specifically to a method for manufacturing a composite bulky yarn, and more specifically, a method for manufacturing a composite bulky textured yarn, and more specifically, a method for manufacturing a composite bulky yarn, in which the yarn forming the core forms a sheath portion having loops and walnuts. The present invention relates to a method for manufacturing a composite bulky textured yarn that has higher shrinkage than the present invention.

(Prior art) Composite bulky yarns have been manufactured by air injection processing not only for polyethylene terephthalate fibers but also for many other materials, but due to cost issues when it comes to different materials, Efforts are being made in various fields to produce composite bulky yarns by a single feed of material.

Among these, low-orientation undrawn yarns and high-orientation undrawn yarns of polyethylene terephthalate fibers have been attracting attention as new materials, and are of great interest, especially for their unique physical properties not found in conventional drawn yarns.

In other words, the high extensibility and high shrinkage properties of undrawn yarns increase the degree of freedom in processing and have the potential for a wide range of applications.

However, the low-oriented undrawn yarn has problems in terms of stability over time and dyeing stability of the yarn quality.

Therefore, the present inventors investigated air injection processing of highly oriented undrawn yarn, but found that highly oriented undrawn yarn was much more stable in terms of stability over time and dyeability than low oriented undrawn yarn. Although there were no problems caused by these characteristics, it was not possible to obtain a bulky yarn with a spun-like texture using a bulky yarn with loops or walnuts obtained simply by air injection processing. There wasn't.

(Object of the Invention) The object of the present invention is to produce a bulky textured yarn capable of exhibiting a spun-like texture using a highly oriented undrawn yarn with stable stability over time and dyeability as a starting yarn. Our goal is to provide the following.

(Structure of the Invention) The present inventors achieved this purpose by cold-stretching a highly oriented undrawn yarn made of polyethylene terephthalate at different stretching ratios and then performing air injection processing. We have discovered what can be achieved and arrived at the present invention.

That is, in the present invention, when manufacturing a bulky textured yarn consisting of a plurality of yarns having a shrinkage difference with each other and having loops and walnuts, at least a plurality of highly oriented undrawn yarns made of polyethylene terephthalate are used. One of the yarns is cold-stretched at a natural draw ratio or higher, and then the cold-drawn yarn and at least one of the highly oriented undrawn yarns or the drawn yarn cold-stretched at a lower than the natural draw ratio are passed from a single feed roller. This is a method for producing a composite bulky textured yarn, which is characterized in that the yarn is simultaneously supplied to an air injection nozzle in an overfeed state.

Here, the polyethylene terephthalate highly oriented undrawn yarn has a birefringence △n of 0.02 to 0.15 and a breaking elongation of 70 to 70.
280%, and the shrinkage rate is about 20 to 70%.

In the present invention, an appropriate composite bulk can only be obtained when at least one of the plurality of highly oriented undrawn yarns is cold-stretched at a draw ratio greater than or equal to the natural draw ratio of the highly oriented undrawn yarn.

Note that the stretch ratio higher than the natural stretch ratio refers to the stretch ratio when the stretch curve is drawn using an Instron under standard conditions and the yield point after necking is exceeded in the stretch curve.

In this way, at least one of the plurality of highly oriented undrawn yarns is cold-drawn to a natural draw ratio or higher, and the other highly oriented undrawn yarns are not cold-drawn, or are drawn at a low draw ratio lower than the natural draw ratio. When the cold-drawn yarn is passed through a single feed roller to an air injection nozzle in an overfeed state, the core of the resulting composite bulky yarn is formed from the yarn that has been cold-drawn at a natural draw ratio or higher. The sheath portion having loops and walnuts is formed from a highly oriented undrawn yarn or a drawn yarn cold-drawn at a lower than its natural stretching ratio.

The present invention will be explained with reference to FIG. 1, which is a process diagram showing one embodiment thereof.

In FIG. 1, a plurality of highly oriented undrawn polyethylene terephthalate yarns 1 of the same quality are cold-stretched between a single feed roller 4 and a roller 3 to a degree higher than the natural stretching ratio, and the rollers 3' and g' The circumferential speed is the same as that of the feed roller 4, and the highly oriented undrawn yarn fed by the rollers 3' and g' is combined with the cold drawn yarn without being stretched, and is overfed from the feed roller 4. The air is supplied to the air injection nozzle 5 in this state.

At this time, the yarn cold-drawn between feed roller 4 and roller 3 shrinks under overfeed conditions, so it forms the core of the resulting bulky yarn and is drawn from rollers 3' and g'. Since the supplied highly oriented undrawn yarn does not shrink even under overfeed conditions, a sheath portion having loops and walnuts of the resulting bulky yarn is formed.

In the manufacturing method of the present invention, the draft rate or overfeed rate can be freely manipulated by adjusting the circumferential speed of the feed roller 4, and the composite structure effect can be further increased.

Further, in the present invention, no heat treatment equipment is required for the stretching process, which is advantageous from the viewpoint of manufacturing costs and application materials.

In the manufacturing method of the present invention, it has been found that the processability is good, the entangled state of the yarn is stable over a considerable yarn speed range, and the processability is good even at a yarn speed of 300 m/min. Gender was also recorded.

As an application example of the present invention, since the material used is a highly oriented undrawn yarn, it is easy to make the spinning-drawing-air injection process continuous, which leads to a significant cost reduction.

It is also possible to obtain a composite bulky yarn with a unique FL fit by changing the single fiber denier, cross section, etc., instead of using the same material.

In addition, in the apparatus shown in Fig. 1, if the feeding amount of each highly oriented undrawn yarn is changed intermittently to improve the entanglement effect in the drawing process before the feed roller, the entanglement of the yarn can be improved intermittently. It is also possible to manufacture slab-like bulk high-grade materials.

(Function) The bulky textured yarn obtained by the production method of the present invention has a sheath because the yarn forming the core is a yarn obtained by cold-drawing a highly oriented undrawn yarn to a rate higher than its natural draw ratio. It has a much higher shrinkage than the yarn forming the part.

For this reason, when heat treatment is applied to a woven or knitted fabric using such bulky textured yarn, the yarn forming the core of the bulky textured yarn shrinks more than the yarn forming the sheath, giving it bulkiness. At the same time, the loops and walnuts in the sheath also shrink, giving it a crisp feel (see Figure 2).

As described above, the composite bulk textured paper obtained by the manufacturing method of the present invention exhibits a spun-like texture, that is, a dry touch and a soft crisp feel, which is not seen in composite textured yarns made of ordinary drawn yarns. It's something you get.

In addition, the composite bulky textured yarn obtained by the present invention is non-torque and is therefore suitable for textile applications (effects of the invention). It is possible to easily obtain a composite textured yarn that exhibits a texture, and its industrial significance is great.

(Example) Two highly oriented undrawn yarns (105 denier/36 filaments) of polyethylene terephthalate fibers were processed using the apparatus shown in FIG. 1 to obtain a composite bulky yarn as shown in FIG.

Table 1 shows the results.

[Brief explanation of drawings]

FIG. 1 is a process diagram showing a method for producing a composite bulky yarn of the present invention, and FIG. 2 is a diagram showing the form of the bulky yarn obtained by the method of the present invention before and after knitting set. 1... Highly oriented undrawn yarn, 2... Guide, 3, 3'. 4...Roller, 4...Yam feeding roller,
5... Air injection nozzle, 6... Delivery roller, 7... Winding up roller.

Claims (1)

[Claims] 1. When manufacturing a bulky textured yarn that is made up of multiple yarns that have different contractions and has loops and walnuts,
At least one of a plurality of highly oriented undrawn yarns made of polyethylene terephthalate is cold-stretched at a natural stretching ratio or higher, and then the cold-drawn yarn and at least one of the highly oriented undrawn yarns or their natural stretching are performed. A method for producing a composite bulky yarn, characterized in that a drawn yarn that has been cold-drawn at a lower drawing ratio is simultaneously fed from a single feed roller to an air injection nozzle in an overfeed state.