JPS5988935A - Production of polyester composite processed yarn for traverse knitting - 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 The present invention is a polyester composite processed yarn for flat knitting which has excellent low temperature setting properties and has a texture suitable for spring/summer flat knit sweaters.
This relates to the A construction method.

In recent years, so-called false twist crimp processing, in which drawn or highly oriented undrawn thermoplastic synthetic fiber yarns are false twisted, has been widely used, and the products obtained by this process have a uniform appearance, high electrical conductivity, and elasticity. It is characterized by controlling sexuality.

However, depending on the application, these product characteristics may not always be sufficient and a unique texture may be required. In order to meet these demands, conventional false twisting processing has been used to feed the yarn being fed under overfeed and being rotated during false twisting, while winding other yarns around it, thereby increasing the winding of the core yarn. A method of creating a yarn with a two-layer structure in which a core yarn is wound around the core yarn (in this case, interfacial entanglement does not occur between the core yarn and the winding yarn) and giving it a cotton-like texture (JP-A-56-1999) 20623, Japanese Patent Application Laid-Open No. 56-20624), or a method of imparting crispness by interfacial fusion between the core yarn and the wrapped yarn (see Japanese Patent Laid-Open No. 57-82538). A paper knitted fabric with a good texture, which is different from that of ordinary false twisted yarn, has been obtained. At this time, the materials used for the core thread and the wound thread are not particularly limited, but polyethylene terrestrial filament threads are generally used.

However, when such polyester processed yarns are used for flat-knit sweater applications, the reality is that they are hardly applicable to this field because of problems with low-temperature setting properties.

In other words, flat-knit sweaters are usually knitted and linked into a product shape, and then steam-set, but polyester has a lower tl and 4 degrees than normal pressure steam, which does not remove the distortion imparted during knitting. b) Because of this,
This is because high pressure setting equipment is required.

To solve this problem, as a way to make setting at a low temperature possible, false twisting is performed at as low a temperature as possible to avoid a strong thermal history, resulting in a low setting temperature of 1! [However, a method for achieving a set effect has been reported for the case of normal false twisting (Japanese Patent Publication No. 48-172
No. 14, JP-A-49-117719, /I?
Publication No. 49-1t1629, Special Publication No. 53-12
(Refer to Publication No. 621), if such a method is used,
Not only does the crimp performance deteriorate, but also partial fusion of the core yarn and the wrapped yarn does not occur, making it impossible to obtain a knitted fabric with a good feel.

In view of this, the present invention has been made through various tests and has discovered an excellent method for obtaining a polyester composite textured yarn for flat knitting that can be set at low temperatures and has a good texture.

That is, in the present invention, the twisted yarn is wound around the core yarn which is being false-twisted by the rotational torque, and is heat-set and then untwisted to cause interfacial entanglement between the core yarn and the wound yarn. Nonana (・When producing an alternately twisted thread-like composite processed yarn, the core yarn is a polyester fiber containing ethylene terephthalate as the main repeating unit and 18osM groups (M is alkali gold M), which is crystallized. degree (Xρ) is 30 to 55 inches, orientation degree (△n) is 0.06 to 0.12, and Xρ/△n is 35
This is a method for producing a polyester composite textured yarn for flat knitting, which uses yarns in the range of 0 to 650 and has various characteristics.

The present invention will be explained in detail below.

As mentioned above, polyester processed yarns generally cannot be set at low temperatures, so even if processed yarns with good texture were obtained, it was almost impossible to enter the field of flat knit sweaters. That is, in the 41-raising process of a flat knit sweater, after the product is knitted and linked, it is washed to remove oils etc. that adhered during knitting, so wrinkles, deformation, etc. that occur during this process are prevented. A steam set process is required. However, since ordinary polyester requires high-pressure cent equipment, it cannot compete with acrylic fibers, etc., which can be produced at 1 cent, in terms of cost and productivity.

In order to solve this problem, the present inventors conducted various autopsies on the yarns that constitute the core of composite processed yarns, and found that when a filament with a highly crystalline and low orientation structure is used as the core yarn, there is a noticeable setting effect. was found to be obtained.

That is, in the composite textured yarn according to the present invention, the wound yarn is wound around the core yarn in alternating four threads, so the properties of the core yarn largely contribute to dimensional changes such as stretching and shrinkage. If the core yarn is stabilized at a temperature comparable to normal pressure steam, the shape of the composite textured yarn as a whole will also be stabilized.

Dimensional stabilization at such low temperatures is governed by the ease with which molecules in the amorphous part of the filament relax, and the lower the molecular orientation and the lower the molecular chain density in the amorphous part, the more relaxed the molecules are l
] is likely to occur.

Therefore, in order to create such a structure, it is necessary to increase the degree of crystallinity, reduce the fraction of amorphous parts, and suppress the orientation of amorphous molecules as much as possible.

Thus, in the core of the two N4 structural yarns according to the present invention,
A polyester fiber having ethylene terephthalate as a main repeating unit and containing -80,M groups,
It has been found that a filament having the following characteristics (a), (b), and (c) can be used.

(a) Crystallinity (Xρ) 30-55% (b)
+m refractive index (△n) 0.06~0.12(c)X
ρ/△n 3 50 ~ 6 5 0 where,
The -803M group (M is an alkali metal) functions to suppress the orientation of the amorphous portion, and is suitably contained in an amount of 1 to 5 moles based on the total acid component).

Furthermore, if Xρ is less than 30 inches or Δn is less than 0.06 inches, the elongation of the yarn increases, and therefore stretching is required during false twisting. However, when stretching is carried out, the pinch of the winding yarn becomes rough and uneven, and the texture is not good:l L (7,1:
In some cases, Xρ is 30% or more and △n is 0.06.
As described above, it is necessary to reduce the elongation. Of course, as long as this winding pitch is permissible in relation to the texture and the tension, stretching and false twisting (simultaneously) may be employed.

On the other hand, those in which Xρ exceeds 55:1. ! ]Rui is 0
．． If the number exceeds 12, when knitted into a knitted fabric, it will only exhibit a hard texture.

More importantly, even if the above conditions (a) and (b) are satisfied, if the value of On the other hand, if the value exceeds 650, problems such as fuzz will occur.

As a method for producing filaments with such physical properties, for example, 3.3 moles of 5-sodium sulfoisophthalate component are copolymerized, and after spinning at a speed of 4000 mm/min, 210"
When polyethylene terephthalate (polyethylene terephthalate) yarn (84 de/24 fils, elongation 50 inches) which was crystallized by heating at C was further stretched at a stretching ratio of 1.1 times and a heater temperature of around 170°C, A filament yarn with Δn=0.0082 is obtained.

Here, the method for manufacturing the filament used for the core is as follows:
Any method such as high-speed spinning, quench-spinning, heating crystallization, etc. may be used, and two or more methods such as high-speed spinning, heating crystallization, etc. may be combined as in the above specific examples.

In short, if the conditions (a), (b), and (c) above are satisfied, the effect will appear.

] N1 is an example of the false twist winding process in the present invention.
) is supplied from the first feed 1-ler (2), and is brought into a false-twisted state by being transmitted with rotational force by the false-twisting device (3). On the other hand, the winding yarn (4) is fed by the second feed roller (5).
It is fed through the guide (9) to the core yarn i11 which is in a false-twisted state so as to be wound around it by its rotational force. In this state, it is heated by a heater (6), passed through a false twisting device (3), a delivery roller (7), and then wound into a winder (8). Layered processed yarn is obtained.

In this case, the winding state of the wound yarn varies depending on the amount of yarn supplied, the heater d1, 1 degree, and the number of false twists, and therefore the form of the two-layer yarn and the stability against tension vary considerably. Therefore, appropriate conditions can be selected depending on the use and purpose.

In other words, the larger the supply amount of the winding yarn (4), the higher the VT of the yarn produced, but from the stability of winding, the core yarn (4) is
Approximately 1.2 to 2.0 times the amount supplied in 1) is appropriate. In order to adjust this 1↓, it is not enough to change the speed ratio of the first feed roller (2) and the second feed roller (5). Instead of strictly regulating the speed, a compensator may be used to regulate the winding tension.

In addition, in order to make a sturdy and stable wound structure, it is recommended to raise the temperature of the heater and fuse a part of the core yarn to form a solid solution between the core yarn and the wound yarn. If the bonding occurs too much, the thermal deterioration of the fused portion will progress and the strength will decrease, so it is necessary to select conditions appropriately.

Furthermore, regarding the number of false twists applied to the yarn, in general, the larger the number of false twists, the tighter the winding pattern 1fAt can be obtained, but if there is too much, yarn breakage will occur, so normal so-called false twisting is not possible. A value larger than the number of false twists used, i.e. a false twisting device (3
) The number of twists immediately before is 2000 o, / V- ~ 6
000 o/f; t/71'L (however, D8 is the denier number of the yarn) is desirable.

Here, the yarn used for the winding yarn may be freely used, such as outer polyethylene terephthalate, chiron, acetate, etc., which are the same as the core yarn. In addition, as for the winding method, in addition to being able to sweep the winding uniformly, even if a method of vibrating the winding point to give a slab effect is applied, it will not work.

As described above, by using a filament with a highly crystalline and low orientation structure as the core yarn of composite processed yarn according to the present invention, it is possible to enter the field of polyester flat knit sweaters, which was previously impossible. It is surprising that a material with good buildability and texture can be obtained.

Hereinafter, the present invention will be described in detail with reference to Examples.

Example 1 A polyester filament yarn (+50 de
/48fi1g) was used as the core yarn fil, and the number of false twists was 2200 t/m using the step 1.

Polyester filament yarn (150 de / 4
8file) was fed as the wound yarn (a) to the first feed roller (2) in an overfeed amount of 30% to obtain a composite textured yarn. When this yarn was knitted into 14G Milano Lip, a knitted fabric with a texture suitable for a flat knit sweater was obtained. The values of Xρ, Δn and Xρ/mu of the filament used as the core yarn and the setting properties of the obtained knitted fabric are shown in the second garment.

The plan for setting is 9 with the knitted fabric stretched by 10% with a gold frame.
After blowing steam at 0°C for 10 seconds, the metal frame was removed and the return rate was measured. If the metal frame returned completely, the set rate was 0%, and if it did not return at all, the set rate was 100%.

Table 1 Table 2 As you can see, the crystallinity (Xρ) is 30 to 55%.
, the degree of orientation (Δn) is 0.06 to 0.12. And Xρ/△
When n is in the range of 350 to 650, a knitted fabric with good centering properties can be obtained.

Example 5 - A polyester copolymerized with 3.5 mol of a sodium sulfoisophthalate component was spun at a speed of 4000 m/min while blowing cooling air directly below the nozzle, and then spun at 210°C without being wound up. Polyester filament yarn (75 de
/ 24 file rXρ=43.5%, Δn=0.
08) as the core yarn, and acetate yarn (,75de/2
Use the guide (9) as shown in the figure.
A two-layer 47e yarn was obtained in the same manner as in Example 1, except that the thread was removed and the winding point was freely vibrated for winding. Two of these yarns were knitted into a 14G jersey while aligning the yarns, and the set rate was measured, and it had a good set property of 92 stitches, and a fancy knitted fabric with good J and 67 stitches was obtained.

[Brief explanation of the drawing]

The figure shows one embodiment of the false twist winding process. Winding thread 5
...Second feed roller 6...Heater 7...
・Delivery ruler-8...Wainter'-9...Guide

Claims (1)

[Claims] (1) The twisted yarn is wound around the core yarn that is being false-twisted due to the rotational torque, and after being heat-set, it is untwisted and the interfacial interaction A. When producing a composite textured yarn with alternately twisted Ja without δ, the core yarn is a polyester fiber containing ethylene prephthalate as a main repeating unit and containing -803M group (M is an alkali metal), which is crystallized. Polyester composite processed yarn for Yokozuna, characterized by using yarn having a degree (Xρ) of 30 to 55, an orientation degree (Δn) of 0.06 to 0.12, and a Xρ/Δn of 350 to 650. manufacturing method.