JPS6034636A - Polyamide false twisted processed yarn and production thereof - 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 A2 Technical Field of the Invention The present invention relates to a polyamide-based plate twisted yarn and a method for producing the same, and more specifically, it relates to a polyamide plate twisted yarn and a method for producing the same.
ij This invention relates to a polyamide plate twisted yarn with excellent thermal properties and a rational manufacturing method thereof.

Previous technology and its problems Polyamide-based board twisted yarn has been known for a long time.

It has superior stretchability compared to temporarily twisted yarn made of polymers such as polyester, and is widely used as a raw yarn for stretch woven and knitted fabrics. However, as the sophistication of sports clothing rapidly increases, the requirements for stretch materials have also become more sophisticated, and it has become difficult to meet these requirements with the polyamide temporary warp yarns that have been used up until now. Spandex is mixed, knitted, and woven for clothing that particularly requires a high degree of stretch, but there is a problem in that it increases costs.

C1 Object of the present invention The present invention provides a twisted yarn made of polyamide continuous filament yarn that can realize a knitted fabric with excellent stretch properties, and a rational manufacturing method thereof.

29 Structure of the present invention The present invention consists of the following configuration.

[(1) Heat treatment gi when the maximum value F (gusim) of dry heat absorption coefficient 1 and the dry heat shrinkage stress show the maximum value in temporarily twisted yarn made of polyamide continuous filament non-woven yarn
Twist processing of a polyamide sheet characterized by having an i degree T (°C) of 0.20D ≧F ≧0.08D Tm≧T≧Tm-25 and a shrinkage recovery rate CR (%) of 15 or more thread. However, D and Tm are the fineness (denier) and fusing temperature (° C.) of the temporarily twisted yarn.

(2) In a method for manufacturing a temporary twisted yarn in which a polyamide continuous filament yarn is supplied to a temporary twisting machine, subjected to heating, setting, and unraveling, the birefringence Δn of the supplied polyamide continuous filament yarn, addition Manufacture of a polyamide-based temporary twisted yarn characterized in that the tension (dulum/denier) and heat setting temperature H (°C) are as follows Method. However, Hm is the melting point (°C) of the boamide continuous filament drawn yarn. ” The present invention will be explained in further detail. The dry heat shrinkage stress according to the present invention is measured as follows. Sample length: 20 cm Temperature increase index: 120 seconds/300°C Initial load = 01 g/denier Number of measurements: 5 times Measure with. FIG. 1 shows an example of the measurement. To find the maximum value F (Durham) of the dry heat shrinkage stress, read the thickest value FA (Durham) of the shrinkage stress in Figure 1 and subtract the initial tension Fo (Durham) from that value.

The value is 1/2.

F=2 (FA FO) The heat treatment temperature T (°C) is the temperature at which the shrinkage stress reaches the maximum value FA, and the melting temperature Tm (°C) is the temperature at which the shrinkage stress becomes zero (Figure 1).

The reduction ratio CR2 (%) is determined as follows.

The measurement procedure and reduction formula are shown below.

Measurement procedure (1) From burn or corn (cheese) to @ contact, use a ka-shichimaki iso with a circumference of about 80 cm) and measure 1/1/1 of the indicated denier.
Make a 10-turn skein by applying a uniform load of 10g or less.

(2) Remove the skein from the skein winding machine and gently apply a load of 1/10 g per indicated denier to remove skein disorder and tangles caused by shrinkage, then apply an initial load 3) of 2 mg per indicated denier, and then Gently remove the load.

(3) Next, the skein with the initial load suspended is immersed in hot water at 98±1°C for 20 minutes.

(4) Take out the soaked skein, remove the initial load, drain the water with absorbent paper, and leave the skein undisturbed for about 12 hours or more to achieve moisture equilibrium.

(5) Hang one end of the skein after it has been left on a hook as shown in the following diagram, and apply an initial load of 2 mg per indicated denier and a load of 51/IDg per indicated denier 2) to the other end to remove the shock. 4) Quickly lower the hook into water at 20°C and 2°C, fixing the hook, and leave it for 2 minutes.

(6) Measure the inside length of the left skein. (Read to the nearest 1■) (7) After measuring the length, gently remove the load under water and leave it under the initial load for 2 minutes.

(8) Measure the inside length of the left skein. (1 = read to the unit) (9) Calculate CR2 (%) from the length of the skein (til+) determined above using formula 62. (Up to 1 decimal place) Note: 1) Work circumference approximately 80 If there is no cmQ 7-volume nucleus,
It is also possible to see a 100m or 1,125m long runner.

2) Total number of threads of 1/10 g of indicated tenier x Kana (2)
0) and the load is the weight in water.

3) The total number of threads (20) in a 2/10100O skein of the indicated denier, and the load is the weight in water.

4) Mix 2.6 drops of surfactant into the water to improve wetting of the yarn surface.

Calculation formula here is 7? : Initial load and inner length of the skein when the load is applied) 11: Inside of the skein with the initial load applied after the load is removed (ill length (mIII)) In the present invention, the polyamide series Me Nylon-6 and nylon-66 can be used as filament yarns.Any fineness and number of filaments can be used, but for stockings it is about 10 denier or more, and for vocal material it is about 40 rotini. Up to 2 filaments or up to 144 filaments can be applied.

The first point in the present invention is the maximum value F(
gram) is 0.20D≧F≧0.08D. The F value of the conventional twisted yarn made of continuous polyamide filaments is 0.06D or less. The F-value is related to the shrinkage force, and influences the shrinkage force at which the knitting yarn resists the restraint while being constrained in a fabric such as a woven or knitted fabric. The present inventors have repeatedly investigated ways to improve the stretch properties of woven and knitted fabrics using polyamide plate twisted yarn, and one of the requirements has been to increase the shrinking ability of the temporarily twisted yarn in woven and knitted fabrics. They found that it was necessary to increase the F-number in order to increase this expression power. In particular, for applications such as tights and swimsuits that require a high stretch, the F value must be 0.08D or more. On the other hand F
If the value becomes too large, problems such as dimensional stability and properties may occur.
．． It is necessary that it is 20D or less.

The second point of the present invention is that the heat treatment temperature T (° C.) at which the dry heat shrinkage stress shows the maximum value is Tm≧T≧Tm −25 . Conventional polyamide plate twisted thread T
is approximately TJII-40, and there is a large difference from the melting temperature Tm. On the other hand, the difference between T and Tm of the polyamide plate twisted yarn of non-explosion J is small. The value of Tm is almost constant once the polymer is determined. Therefore, if the polymer types are the same, the value of T will be higher for the polyamide plate twisted yarn of the present invention. The T value affects the thermal stability of the temporarily twisted yarn. In this respect, the thermal stability of the polyamide plate twisted yarn of the present invention is high.

The sixth point of the present invention is that the shrinkage recovery rate CR (%) is 15 or more. The CR value is a measure representing the amount of shrinkage and is an essential element to have sufficient stretchability. It is preferable that the CR value is as large as possible,
It is necessary that the number be 15 or more while satisfying the above two requirements. The three requirements of the polyamide plate twisted yarn according to the present invention have been described individually above, but in order to realize the preferable effects of the present invention described below, the polyamide plate twisted yarn must add 414 of all these requirements. Must.

The second invention in this MJi will be explained. As the temporary twisting machine according to the present invention, one having a feed roller group, a heat treatment device, a heating device, and a winding device can be used, but the heating device is set to a ratio of solved tension to tension of 12 or less. Something that can be used is preferable, and a pin temporary twisting device is not suitable. The birefringence Δn of the polyamide continuous filament yarn supplied in the present invention is 5xl
It needs to be O-3 or higher. The method of the present invention can be carried out by supplying semi-drawn yarns and drawn yarns with birefringence within this range to a temporary twisting machine, or by continuously feeding undrawn yarns to a temporary twisting machine while being stretched. .

Next, the head office (in the second invention, the applied tension t (grams/
Denier) is required to satisfy 08≧t≧04. The above range is considerably higher than the value taken in the conventional temporary twisting method.

In the case of pin temporary twist9, the value of t is usually 0.1'0 to 012.
Even if there was a temporary twist of the friction, the actual value did not exceed 04. In general, increasing the strength of the welding force also increases the unraveling tension, which results in a decrease in the shrinkage ratio, so the tension of the welding process must be kept as small as possible within the range that maintains processing stability. 08≧t≧04 in the present invention goes against this idea, but due to the special combination with the heat cent temperature H described in the first section, it can be expected! It has a special effect that J did not have.

In the method for producing a polyamide plate twisted yarn of the present invention, the heat setting temperature H (°C) must be within the range of Hm-10≧H≧Hm-25. Hm is the melting point (°C') of the supplied polyamide continuous filament yarn when it is drawn. The value of H generally taken in the conventional temporary twisting method does not exceed Hm -30.

The heat setting temperature H corresponds to the surface temperature of the heater of the temporary twisting machine, but if the heater temperature is set too high, fusion between the filaments will occur and the appearance and shrinkage properties of the processed yarn will deteriorate, resulting in unsatisfactory processed yarn. Must not be. It was considered impossible to raise the heater temperature higher than Hm -25 when obtaining a general processed yarn. Hm -10≧H≧Hm -25 of the present invention is contrary to the above idea.

That is, the applied tension t (grams/denier) should be 08 ≧ t ≧ 04, or the heat set temperature H (℃) should be Hm-1
Setting 0≧H≧Hm −25 means that when used alone, only a processed yarn with a low degree of shrinkage and/or a poor appearance quality due to fused and undissolved Nene can be obtained. However, by combining the two, there is no fusion.

We discovered the surprising fact that it is possible to obtain a temporarily twisted yarn with no reduction in shrinkage, and achieved a 4% success rate. The method of the present invention is not limited to conditions other than the above, such as the temporary twisting speed, but the temporary twisting speed is 600 m/xnin.
It is particularly effective between 1000 m/min and 1000 m/min.

9 Functions and Effects of the Present Invention One of the effects of the temporarily twisted yarn made of the polyamide continuous filament yarn of the present invention is that the fabric using the textured yarn has a good stretch performance. In other words, when the 4-knit fabric is dyed, it shrinks sufficiently.4) The fabric has a high stretchability after dyeing, but the temporary twisted yarn of the present invention The maximum value of shrinkage stress F is extremely high, and it has enough shrinkage power to overcome the tension in the dyeing process and the binding force that acts between adjacent yarns inside the knitted fabric, making it a product with high stretch. At the same time, it becomes a product with excellent tensile strength.Furthermore, when the tentatively twisted yarn of the present invention is used, the high stretchability of the product with excellent heat resistance can be maintained for a long time.Especially on woven and knitted fabrics. is dyed and then finished and set, but at this time some of the stretchability of the woven or knitted fabric disappears.Using the temporary twisted yarn of the present invention has the advantage of being able to improve this problem.Furthermore, polyamide Temporarily twisted yarns are often used by inter-knitting with cotton yarns or acrylic yarns, acrylic yarns, ζ-thin yarns, etc. Examples are socks, training wear, sports wear, etc. As shown, they have almost no stretch. When cross-knitted with spun yarn, the temporary twisted yarn must have particularly high stretchability, but the temporary twisted yarn of the present invention can fully meet this requirement.

The advantage of the method for producing polyamide plate twisted yarn of the present invention is that it can be carried out without major modification of the equipment. Another advantage is that there are fewer restrictive conditions for increasing the temporary twisting speed. That is, in general, as the pre-twist processing speed increases, the rotational speed of the yarn increases, which causes the yarn to rotate and vibrate at various parts of the yarn path. A so-called ballooning phenomenon occurs.

Such ballooning reduces the stability of temporary twisting and causes yarn breakage and yarn unevenness. Therefore, the measure generally taken during high-speed temporary/twisting processing is to increase the temporary/twisting tension to suppress the occurrence of ballooning. However, if the tension is increased excessively, the shrinkage ratio of the tentative twist yarn decreases in the conventional technique, which is not preferable.

On the contrary, the method of the present invention is effective in a region where the applied tension A is high, and therefore it is an advantageous method for high-speed stable machining without the occurrence of ballooning.

Example 1 Nylon-6 chips were melted by a conventional method, and the spinning speed was 5.
The yarn was spun at 200 m/min and wound around the 1-1 drum to obtain a semi-drawn yarn of 89 denier and 24 filaments. The ventral refraction Δn of this semi-drawn yarn was 39×10 −3 . Further, this semi-drawn yarn was drawn by a conventional method, and the resulting drawn yarn had a melting point of 217°C. This semi-drawn yarn was supplied to a drawing and pre-twisting machine manufactured by Murata Tsukiki Co., Ltd., and various pre-twisted yarns were prepared by changing the processing speed, heat setting temperature and draw ratio as shown in Table 1. The applied tension t(
grams/denier) are also shown in Table 1. The fineness (denier) of the temporarily twisted yarn obtained by the above processing is 1
Strength (grams/denier), elongation (%).

Shrinkage recovery rate CR (%), maximum value of shrinkage stress F (grams), shrinkage stress does not show the maximum value and heat treatment ↓1 ■ 1 temperature T (r
:) and the melting temperature Tm (°C) are shown in Table 2.

A 28G inklock silk fabric was knitted using these pre-twisted yarns, and the appearance and tension of the knitted fabric with a stretch ratio of 9 in the warp direction after dyeing were evaluated. The results are shown in Table 2. The stretch rate was measured by the following method.

Test procedure (Hold out test pieces of 15 cm x about 3 Q cm and collect 3 pieces each in the horizontal direction.

(2) Using a constant speed extension type tensile test with a self-recording device,
Fix the grips at a distance of 20 cm. Apply an initial load equal to the weight of a 5 cm x 1 m thick sample and secure it to the grips.

(3) Stretched to 18 grains at a pulling speed of 20 cm/min.

Measure the grip distance at that time (read to the nearest 1/2 mm). The elongation rate (%) is determined by the following formula and expressed as the average value of the three sheets (to one decimal place).

Here, l: Grabbing interval (-) 11: 1.8 ] (Grabbing interval (min) when stretched in g dimension) As is clear from this table, the pre-twisted yarn of the present invention has stretchability 1 knitted fabric appearance, It also has excellent waist tension.

Table 1 Temporarily twisted yarn manufacturing conditions

[Brief explanation of drawings]

Figure 1 shows the maximum value F (grams) of dry heat shrinkage stress. Heat treatment temperature T (1:) and fusing temperature Tm at that time
It is a figure explaining (degree Celsius). Patent applicant Toshi Co., Ltd.

Claims (2)

[Claims] (1) The maximum value F (Durham) of dry heat shrinkage stress and the heat treatment temperature T at which the dry heat shrinkage stress shows the maximum value in temporary twisted yarn made of polyamide continuous filament yarn
(t:) is 020D≧F≧008D Tm≧T≧Tm-25, and the shrinkage recovery rate CR (%) is 15 or more. However, D and Tm are the fineness (denier) and fusing temperature (° C.) of the temporarily twisted yarn. (2) In the method for manufacturing a temporary twist yarn in which polyamide continuous filament yarn is supplied to a temporary twist processing machine, heat set, and unrolled, the drawing force 1 (folding Δn, addition tension) of the supplied polyamide continuous filament yarn is t (grams/denier) and thermal cent temperature ■] (°C) are as follows: Δn≧35x10-'08≧t≧04 Hm-10≧H≧Hm-25 Method, where Hm is the melting point (°C) of polyamide continuous filament drawn yarn.