JPS63182439A - Production of composite fancy yarn - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

Detailed Description of the Invention Firstly, in the second aspect of the present invention, an undrawn yarn of thermoplastic synthetic fiber is used as a core yarn, and a knot portion and a base yarn portion in which the undrawn yarn of thermoplastic synthetic fiber is entangled as a sheath yarn are formed. It forms threads with intermittent threads. What is important here is to use undrawn yarns for both the core yarn and the sheath yarn to form a yarn having knots. As the undrawn yarn, in addition to undrawn yarn obtained by ordinary spinning, highly oriented undrawn yarn obtained by high-speed spinning can be used, and highly oriented undrawn yarn is preferably used. The above-mentioned undrawn yarn usually has a breaking elongation of 70 to 500.
% is preferably used. For undrawn yarns with a breaking elongation of less than 70%, not only the ground yarn section but also the 9-knot section are likely to be stretched during the stretching process described below, so the difference in yarn diameter between the 3-knot section and the ground yarn section cannot be made sufficiently large. Sometimes. On the other hand, if the elongation at break exceeds 500%, the yarn may be stretched by tension when forming the yarn having the knots, making it impossible to form the yarn having the knots. Particularly preferably highly oriented undrawn yarn with a breaking elongation of 90% to 250%, a breaking elongation of 80%
~300% nylon 6 highly oriented undrawn yarn is used.

The yarn itself having the above-mentioned knots is manufactured by a conventionally known method, and the method is not limited. for example.

A method in which a real twist is applied using a ring twisting machine, etc., and a large amount of sheath yarn is partially wound around the core yarn, and a false twisting process is used to wind the sheath yarn around the core yarn to form a single-wound part and a triple-wound part. how to make
Methods such as changing the supply speed of the sheath yarn through fluid jet processing, or temporarily applying resistance to the sheath yarn to change the amount of supply to the fluid jet nozzle to entangle the sheath yarn with the core yarn are adopted.

In the yarn having knots formed as described above, the 9-knot part has more sheath threads than the ground thread part, and they are entangled regularly or irregularly, and the sheath threads are regularly or more than three times wrapped around the core thread. The core yarn is wrapped around the core yarn, or a large amount of sheath yarn is irregularly intertwined with the core yarn. On the other hand, in the ground yarn part, the core yarn and sheath yarn are entwined in a single spiral shape, the core yarn and sheath yarn are entangled with each other with almost no difference in length, or the core yarn and sheath yarn are almost parallel. is in a state.

Next, the yarn having knots formed as described above is drawn. As a result of this stretching, the knot portions with a large yarn diameter are hardly stretched, and the ground thread portions with a small thread diameter are preferentially drawn, and the yarn diameters of the first knot portion and the ground thread portion are further increased. Here, the drawing ratio is usually preferably in the range of 1.2 to 4.5 times depending on the elongation at break of the undrawn yarn, the use of the obtained yarn, etc. When the draw ratio is less than 1.2 times, it is difficult to make the difference in yarn diameter between the 1st knot part and the ground yarn part sufficiently large.On the other hand, when a large draw ratio of more than 4.5 times is adopted, the difference in yarn diameter between the 1st knot part and the ground thread part cannot be made sufficiently large. Also, the first knot part and the ground thread part may not be clearly defined.

The above-mentioned stretching in the present invention may be either cold stretching performed at normal room temperature or hot stretching performed by heating with a heater, hot bottle, etc. To emphasize this further, cold drawing is preferable to hot drawing, in which the difference in tensile stress between the knot part and the ground thread part is reduced by heating.

In the present invention, since undrawn yarns or highly oriented undrawn yarns are used as the core yarn and sheath yarn, unstretched portions remain at knots that are not subjected to the stretching action. Therefore, since shrinkage may occur in post-processes such as dyeing, it is preferable to heat-set after drawing. The heat-setting temperature is preferably 150° C. or higher and below the melting point, although it depends on the degree of orientation of the undrawn yarn. This heat setting is performed, for example, after cold stretching, using a heater or the like to allow shrinkage, to maintain a constant length, or to a stretched state. Also.

It may also be used by false twisting after cold stretching and heat setting by heat setting during this false twisting. The heat setting after cold stretching may be performed in series with the cold stretching, or may be a separate process. Furthermore, heat setting may be performed by false twisting simultaneously with hot stretching.

Hereinafter, one method of the present invention will be explained in detail based on the drawings.

FIG. 1 shows an example of the method of the present invention, in which undrawn yarn YI as a core yarn is given false twist by a twisting device 3 provided between rollers 1 and 4. This twisting device 3 is a false twisting spindle.

Any device that has a twisting action, such as an air nozzle that generates a swirling flow, may be used. On the other hand, the undrawn yarn Y2, which is to be used as a sheath yarn, passes through the rollers 2 and the guide 5, and is merged with the undrawn yarn Y1 between the rollers 1 and the twisting device 3. At this time, by increasing the rotational speed of the roller 2 relative to the roller 1, the undrawn yarn Y2 moves back and forth intermittently from point A to point B using the guide 5 as a fulcrum, as shown in FIG. A thread is formed which alternately has a base yarn part a in which the sheath thread is wound in a single layer around the core yarn, and a knot part in which the sheath yarn is wound in three layers around the core yarn. The strip is drawn between roller 4 and roller 6, which rotates at a higher speed. At this time, the knot portions are hardly stretched, and only the ground yarn portions a are preferentially stretched. As a result, a composite fancy yarn according to the method of the present invention having a larger difference in yarn diameter between the knot portion and the ground yarn portion a as shown in FIG. 3 is formed, and is wound up as a package 8 by the winding roller 7. In addition, the example shown in FIG. 1 is an example in which a false twisting heater is not used.

(Function) As mentioned above, in the method of the present invention, undrawn yarn is used as the core yarn and sheath yarn, and the core yarn has intermittent knots in which the sheath yarn is entangled more than the base yarn. Since strips are formed and drawn, the ground yarn portion is thinned by this drawing, and the difference in yarn diameter between the 9-knot portion and the ground yarn portion becomes large.

In other words, in the method of the present invention, due to the high elongation of the undrawn yarn and the difference in yarn diameter between the knot and the ground yarn, the so-called stress concentration phenomenon in which elongation stress during drawing is concentrated in the ground yarn where the yarn diameter is small, can be avoided. It is something to be used.

As a result, the ground yarn part of the yarn having the pre-formed knots is drawn preferentially, and the 9th knot part is hardly drawn, resulting in a fancy yarn in which the ratio of the yarn diameters of the 9th knot part and the ground yarn part is extremely large. It is formed.

(Example) Next, the present invention will be specifically explained with reference to Examples.

Example 1 According to the process shown in FIG. 1, polyethylene terephthalate highly oriented undrawn yarns with a breaking elongation of 110% (birefringence 51 x 10-'') were prepared as threads Y, Y, respectively.
36f was used and processed under the following conditions. On this occasion.

A false twisting spindle was used as the twisting device.

Spindle rotation speed 22.5 x 10' Roller 1 surface speed 125m/a+in Roller 2 surface speed 2
31■/sin Difference in yarn supply amount between rollers 1 and 2 84.
8% Surface speed of roller 4 129m/win Surface speed of roller 5 187cm/sin Difference in yarn supply amount between rollers 1 and 4 3.2% Number of false twists 1800T/M Stretching ratio 1.45x Fabric before stretching The ratio of the yarn diameter of the knot part to the yarn part was 2.7, and the ratio of the yarn diameter of the knot part to the ground yarn part of the obtained composite fancy yarn was 3.4. This composite fancy yarn was then subjected to constant length heat treatment using a heater at 200°C.

The obtained yarn was used as the weft, and polyethylene terephthalate false twisted yarn 150d/48f was used as the warp.

Weft density: 65/2.54cs, warp: 75/2.54
A C1l plain woven fabric was woven. The resulting woven fabric had knots that appeared convexly on the surface of the fabric, with the nine knots being very clear, and had an excellent fancy effect.

Example 2 The same highly oriented undrawn polyethylene terephthalate yarn as in Example 1 was used as the core yarn and sheath yarn, and the overfeed rate of the core yarn was 1% and the overfeed rate of the sheath yarn was 20%. The sheath yarn was supplied to a fluid jet nozzle (kuslan nozzle) while applying resistance intermittently and changing the supply amount of the sheath yarn.

By injecting 7 kg/cd of compressed air using the fluid injection nozzle, the core yarn is intertwined with a large amount of sheath yarn, and the knots having loops are intertwined with the core yarn and sheath yarn with almost no difference in yarn length. A yarn having alternating loop-free ground yarn portions was prepared, and this was drawn at a drawing ratio of 1.3 times. The ratio of the yarn diameter of the node portion to the yarn diameter of the ground yarn portion before Nobunshin was 2.5, but after stretching it was 3.0.

Subsequently, a fixed length heat treatment was performed using a heater at 200° C., and knitting was performed using a commercially available 20G circular knitting machine. A knitted fabric with extremely good knitting properties and an excellent fancy effect with clear 9-knot parts was obtained.

(Effects of the Invention) As described above, the present invention uses an undrawn yarn as a core yarn and a sheath yarn, entangles the sheath yarn with the core yarn to form a yarn having knots, and this yarn Since the threads are stretched, it is possible to easily obtain a composite fancy yarn in which the ratio of the yarn diameters of the 9-knot part and the ground yarn part is extremely large and the yarn form is good. Therefore, when this yarn is knitted or woven, the two-knitted part becomes extremely clear, and a woven or knitted fabric having an excellent appearance with a fancy effect can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a process schematic diagram showing an example of the method of the present invention. FIG. 2 is a schematic side view showing an example of a composite fancy yarn before drawing by the method of the present invention, and FIG. 3 is a schematic side view showing an example of a composite fancy yarn obtained by the method of the present invention.

Claims (1)

[Claims] (1) Forming a yarn having intermittent knots in which an undrawn yarn of thermoplastic synthetic fiber is entangled as a sheath yarn around a core yarn of undrawn yarn of thermoplastic synthetic fiber, and then drawing this yarn. A method for producing a composite fancy yarn characterized by: