JPS5920770B2 - Manufacturing method of special false twisted yarn - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method of heat-setting at a temperature higher than the heat-softening point of the yarn with a lower heat-softening point when false-twisting at least two types of multifilament yarns with different heat-softening points. This invention relates to a method for producing special false twisted yarn.

In recent years, the production method of fused yarn aiming at crispness has been attracting attention, and one example of this production method is to align two or more types of yarns with high and low heat softening points to soften the heat setting temperature. A method in which yarns with a high degree of softening are crimped in a state where the fibers are open by false twisting at a temperature higher than a low point, and the yarns with a low degree of softening are bonded in a spiral shape (Japanese Patent Publication No. 1973- 8951).

However, the yarn produced by this method has low strength and elongation, and is prone to snarling, resulting in very poor knitting properties.

Also, from another point of view, since the method involves aligning and false twisting, it is necessary to perform additional twisting when knitting, which increases the number of steps and deteriorates knitting properties.

An object of the present invention is to provide a method for producing yarn with good knitting properties and excellent crispness in a single step without the above-mentioned drawbacks.

For this purpose, the present invention has the following configuration.

That is, in the present invention, when at least two types of multifilament yarns having different thermal softening points are aligned and subjected to false twisting,
A method for producing a special false-twisted yarn, characterized in that the at least two types of multifilament yarns are mixed before being false-twisted and heat-set at a temperature higher than the thermal softening point of the yarn with a low thermal softening point. It is.

The present invention will be explained below with reference to the drawings.

In the figure, multifilament yarns A and B are unwound from husband packages 2 and 1, pass through guides 4 and 3, are aligned by guide 5, pass through mixing device 6 and guide 7, and are delivered to first feed roller 8. Supplied.

Multifilament yarns A and B have different thermal softening points.

For example, multifilament yarns made of the same polyester may have different thermal softening points.

As a means for mixing fibers, a fiber mixing device shown in the figure (a combination of an electric fiber opening device in addition to the pneumatic force 6, or a mechanical device) is used.

Now, in the case of an air-type fiber mixing device, the tension during passage is 0.
It is preferable to keep it within the range of 0.01 g/d to 0.04 g/d from the viewpoint of crispness and knitting properties.

The reason why the fibers are mixed here is to prevent the yarn from becoming coarse and hard and give it a soft texture.

The multifilament yarns A and B supplied to the first feed roller 8 are fed to the guide 9, the first heater 10, the false twist spindle 11, the second feed roller 12,
It passes through a guide 13 and a second heater 14 to reach a third feed roller 15, passes through guides 16, 17, and 18, and is wound up into cheese 20 by a winding drum 19.

Here, C is a special false twisted yarn.

The multifilament yarns A and B are fed to the first feed roller 8.
The fibers are heated in a mixed state between the fibers and the false twisting spindle 11, and then heat set by the first heater 10 at a temperature higher than the heat softening point of the yarn A, which has a low heat softening point.

The second heater 14 heat-treats the yarn in the same way as in the case of normal two-stage heater false twisting.

In the thus obtained special false twisted yarn C, fibers with a low softening point are bundled in areas with a low degree of blending, and fibers with a low softening point in areas with a high degree of blending are thermally degraded and hardened. ing.

As described above, according to the present invention, a special false-twisted yarn with good knitting properties that does not require additional twisting, and has a crisp and soft texture can be easily produced.

Example Multifilament yarn A was polyester multifilament yarn (50d/24f1, thermal softening point 240°C, water shrinkage rate 11.2%), and multifilament yarn B was polyester multifilament yarn (75d/36f1, thermal softening point 220°C, A special false twisted yarn was produced using the apparatus shown in the figure using a ring water shrinkage rate of 15% and easy dyeing.

Conditions: Tension: 0.02.9/d, Mixing device: Pneumatic, Pneumatic pressure: 3.6 kg/i 6 G, First feed ratio (first feed roller 8 to second feed roller 1
z; 13%, second feed ratio (second feed roller 12
~Third feed roller 16); +10%, spindle rotation speed; 3 i i, o o orpm twist number; 2500
T/M, first heater temperature: 235°C, second heater temperature: 210°C.

For comparison, the fiber blending device was removed and yarn was also produced in the case of pulling.

The physical properties of the resulting yarn are shown in the table below.

Here, the method for measuring each substance is as follows.

Each sample was wound 8 times with a length of 1 m.

Strength (g/d): Tested using a Schopper testing machine at a gripping interval of 50 cIIL and a tensile rate of 50±36111/min.

The cutting strength (2) and the fineness (d) are shown as values obtained by dividing the former by the latter.

Elongation rate (g): Same as above, elongation E (cx) during cutting, crimp contraction between grips (to), elastic pull (g)
and crimp fastness (g): After performing the prescribed heat treatment and drying, a load of 0.2 g/d was applied and the length was read 1 minute later as a, and then 0.00
Multiply by 2g/d and read the length after 1 minute and take it as b, and multiply by 0.02g/d and take the length after 1 minute as C.

demand.

Elastic pull, ring water shrinkage rate determined by ring water treatment (
g); Apply a load of 0.1.9/d to the thread that has been cut in a predetermined manner, and measure the length a after 30 seconds.

The entire sample is dried after being treated with ring water without any load, and then a load of 0.1 g/d is applied again to determine the ring water shrinkage rate.

Knitting property (Snarke/m): Hold a 1 m long sample horizontally and set the interval to 50 crr.
It is expressed as the number of Snarls when set to L.

The yarn of the present invention was superior to conventional yarns in terms of knitability, strength, and elongation.

[Brief explanation of the drawing]

The figure is a side view of an apparatus implementing the invention. 6: Mixing device, 11: False twist spindle, C: Special false twist processed yarn.

Claims (1)

[Claims] 1. When at least two types of multifilament yarns with different thermal softening points are aligned and subjected to false twisting, the at least two types of multifilament yarns are mixed before false twisting and the yarn has a low thermal softening point. A method for producing a special false twisted yarn characterized by heat setting at a temperature higher than the thermal softening point of the yarn.