JPH02139442A - Production of complex yarn - Google Patents

Abstract

PURPOSE:To obtain a complex yarn which is used to produce a high-density and water-repellent cloth for rain coats or umbrellas by interlacing the multifilament core yarn with extremely fine multifilament of high elongation, then false-twisting the interlaced yarns. CONSTITUTION:The multifilament core yarn is combined with extremely fine multifilament yarn of high elongation to be fluffing fibers and they are interlaced. Then, the interlaced yarn is false-twisted at such a temperature as the boiling water shrinkage of the multifilament core yarn does not change (for example, 130 deg.C in nylon 6, 160 deg.C in nylon 66 150 deg.C in polyethylene terephthalate and 140 deg.C polybutylene terephthalate) to give the subject complex yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to a method for producing a composite yarn for use in high-density water-repellent fabrics used for raincoat fabrics, umbrella fabrics, sports clothing, and the like.

(Prior art) Conventionally, it has been proposed and put into practical use that in order to make high-density fabrics water repellent, the surface is covered with fine irregularities containing ultra-fine fibers, treated to make them water repellent, and then calendered. Publication No. 61-70043).

The yarns used to make this fabric include (A) a yarn made by mixing two or more ultra-fine multifilaments with different heat shrinkage rates by means such as blending, twisting, or entangling, and CB) a single yarn. Yarns made of multifilament yarns subjected to bulky processing such as wooly processing, or (C) 2 with differential heat shrinkage.
There are yarns made by woolly processing mixed yarns made of the above-mentioned ultra-fine multifilaments.

However, when yarn A is used, heat treatment is performed in the post-processing process (dying process) to shrink the high-shrinkage yarns and lift the low-shrinkage yarns, giving fine irregularities to the surface of the fabric. . However, in high-density fabrics, fine irregularities are difficult to form due to the strong binding force between the filament bundles that make up the fabric, so it is not only difficult to select the conditions for creating fine irregularities through heat treatment during the dyeing process, but also two types of The difference in the amount of shrinkage of the yarns described above must be greater than a specific value, and the type of yarn used is also limited.

On the other hand, when a fabric is made using B or C yarn, in order to make the fabric roughly three-dimensional through the dyeing process, the shrinkage rate of the bulky yarn that goes through the dyeing process must be high. However, since the ordinary URI-7JIJI yarn is heat-set, it has a low heat shrinkage rate, which makes it difficult to select conditions for developing fine irregularities in the dyeing process.

As a method of treating the fabric under normal dyeing processing conditions to cover the surface of the fabric with fine irregularities, we use threads with fine floating threads formed on the surface of filament bundles, such as Tokuko Sho 62-3.
Using the technique disclosed in Japanese Patent No. 5493, it is possible to use a yarn in which ultrafine fibers are wound around a core yarn in the form of a continuously reversed alternately twisted yarn. If this yarn is used to weave at a high density, it is possible to obtain a '45 fabric with a high fabric density (cover factor) as shown in the example of JP-A-63152439. However, in order to achieve higher water repellency, it is desired that the fabric shrinks during the dyeing process, and methods such as relaxing the tension as low as possible are used, but the process conditions The problem is that it is difficult to control.

(Objective of the Invention) The object of the present invention is to form fine unevenness loops on the surface of a filament bundle in advance so that the surface of the fabric is covered with fine unevenness, and to process the fabric under normal dyeing conditions. The object of the present invention is to provide a composite yarn which has a large shrinkage even when the fabric is used, and can therefore have a high fabric density to obtain an extremely water-repellent fabric.

(Structure of the Invention) In order to achieve the above-mentioned object, the present inventors conducted various intensive studies and found that the core yarn is a core yarn that shrinks to the same extent as ordinary synthetic fiber fabric during the dyeing process and is not substantially heat-treated. It has been found that a composite yarn using a multifilament and an ultra-fine multifilament whose yarn length is longer than the core yarn as a floating yarn to form minute loops or minute floats is useful.

Based on this knowledge, the present inventors conducted further investigations and arrived at the present invention.

That is, in the present invention, after a multifilament yarn serving as a core yarn and a highly elongated ultrafine multifilament are interlaced and subjected to an interlacing treatment, the multifilament yarn serving as a core yarn is substantially contracted in boiling water. This method of manufacturing composite yarn is characterized by performing false twisting and crimp processing at a humidity where the ratio does not change.

In the present invention, after the multifilament yarn serving as the core yarn and the ultra-fine multifilament with high elongation are combined, false twisting and
Since it is untwisted, the filament yarn (hereinafter referred to as core yarn) in which ultra-fine multifilaments 1 to 1 with high elongation become the core yarn during false twisting.
The yarn length becomes longer than the core yarn, and when it is untwisted, the difference in yarn length becomes a fine loop, and when it is made into a fabric, the ultrafine multifilament mainly forms fine irregularities.

At this time, if the ultra-fine multifilament simply floats on the core yarn and forms fine loops, the fine loops will rise up from the core yarn when rubbed during the yarn handling process (warping, beaming, weaving, etc.). , it becomes difficult to maintain the uniformity of the thread thickness. Therefore, the core yarn (heavy wire multifilament) must be intertwined with both filaments, and for this purpose, the core yarn and high elongation multifilament must be intertwined before the false twist crimping process. In addition, when the two types of yarns are false-twisted and untwisted and then subjected to interlacing treatment, if the tension is high, the filaments cannot be entangled with each other, so the entangling treatment must be performed at a low tension. However, in this case, the multifilament of the core yarn also becomes floating, and the loops of the ultra-fine multifilament become too large. Not only does it cause sagging on the surface of the 15-sheet fabric, reducing the quality of the 15-sided fabric,
Weaving and knitting using such yarns is undesirable as it significantly reduces production efficiency. As a method for the interlacing treatment, so-called interlace treatment using compressed air is preferably used.

The present invention involves intertwining the core yarn and the multifilament that will form the floating yarn by forming minute loops in the core yarn and the ultra-fine multifilament that will become the floating yarn, and then pre-interlacing the yarn lengths with a difference in thread length. In addition, when fabric is made from this yarn and dyed, the binding force when the core yarn shrinks due to the difference in yarn length is minimized so that the core yarn can shrink even under normal conditions. Another characteristic is that it is restrained. Therefore, if the core yarn multifilament and the ultra-fine multifilament are simply intertwined or mixed, the shrinkage of the high-shrinkage yarn will be suppressed by the ultra-fine multifilament, so special dyeing processing conditions are required. It's not fit for purpose.

When the fabric using the composite yarn of the present invention is dyed, it is preferable that the shrinkage rate of the core yarn is larger than that of the floating yarn (fine loop) because the uneven floating yarn covering the surface of the fabric will become larger, but at least the same or more, the object of the present invention can be achieved.

In addition, by dyeing a fabric using the composite yarn of the present invention, it shrinks to the same extent as a normal synthetic fiber fabric and has a higher density than the fabric before dyeing, that is, a fabric with a large cover factor. , it becomes possible to further improve water repellency. This method repels water droplets with the fine irregularities on the surface of the fabric and further shrinks the high-density fabric, thereby increasing the density of the fabric and achieving a waterproof effect. It goes without saying that the effect will be further enhanced if calendering and water-repellent finishing are performed.

Needless to say, when dyeing a fabric using the composite yarn of the present invention, the water repellent effect will be further enhanced if conditions are selected in which the fabric is not shrunk to the same extent as ordinary synthetic fiber fabrics, but shrinks more than that.

In order for a fabric using a composite yarn with fine irregularities (loops) floating threads formed on the surface of the filament yarn to shrink to the same degree as ordinary synthetic fiber fabric, the core yarn must be heated to boiling water equal to or higher than that of ordinary synthetic fiber. It is preferable that the length of the floating yarn is 10% or more longer than that of the core yarn and/or that the floating yarn has a boiling water shrinkage rate of should be lower than that of the core yarn.

For example, Japanese Patent Application Laid-Open No. 49-1983 discloses a method of making a composite yarn that forms fine unevenness (loop) floating yarn on the surface of filament yarn.
Various proposals have been made in Japanese Patent Publication No. 72443, Japanese Patent Publication No. 62-35493, Japanese Patent Application Laid-Open No. 61-132646, etc., but all of them involve the process of false twisting, crimping, or false twisting, heat setting, and untwisting. The purpose of the present invention cannot be achieved because heat setting reduces the shrinkage rate of the entire filament bundle and therefore of the core yarn. Therefore,
In order to form fine unevenness (loop) floating yarn on the surface while maintaining the shrinkage rate of the core yarn at a high level, it is necessary to perform the false twisting/untwisting process without substantially heat setting the core yarn. . At this time, by using a multifilament with high elongation as the floating yarn, the multifilament stretches when it wraps around the core yarn, increasing the length of the yarn, and is entangled with the core yarn multifilament during untwisting. Fine loops are formed due to the difference in yarn length, resulting in an uneven surface.

When a composite yarn is made by using filaments with different heat setting properties as a floating yarn and a core yarn, it goes without saying that the floating yarn may be heat-letted after false twisting. In addition, when the multifilaments for the core yarn and the multifilaments for the floating yarn are combined and intertwined, it is a common practice to supply a larger amount of the multifilament for the floating yarn than that for the core yarn. If the matrix is too large, the loops of the floating multifilament will become too large, causing a so-called fastener phenomenon, so the difference m (overfeed amount) is preferably about 6% at most.

The higher the shrinkage rate of the core yarn, the more remarkable the efficiency of the present invention, so it is preferable to use a core yarn with a boiling water shrinkage rate of 10% or more. Such yarns include nylon 6, nylon 66, nylon 6/nylon 66 copolymer, cold-drawn polybutylene terephthalate 1 and polybutylene terephthalate 1, partially oriented polyethylene terephthalate and polybutylene terephthalate. There are threads, and the higher the molecular weight, the higher the shrinkage stress, so it is preferable.

In addition, the temperature at which the boiling water shrinkage rate of the core yarn does not change can be easily determined by experiment, but for nylon 6, it is approximately 130℃,
The temperature is approximately 160°C for nylon 66, approximately 150°C for polyethylene terephthalate, and approximately 140°C for polybutylene terephthalate, but it varies depending on processing speed, heat treatment time, etc.

As a method of obtaining a composite yarn with a core-float structure without reducing the boiling water shrinkage rate of the core yarn, there is a so-called two-layered Taslan yarn, which is treated with compressed air while changing the supply amounts of the core yarn and the float yarn.

Also. As an example of using ultra-fine thread as a floating thread,
494@ Publication, but in this case, the loops of the floating yarn are large, and snarls or knots are formed locally, and fine irregularities are not formed on the surface of the fabric, so the present invention cannot achieve its purpose.

Polybutylene terephthalate (Special Publication Act 1986-36)
No. 107) and conjugate yarn (Special Publication No. 1986-49)
376 and JP-A-59-216939) is also known, but this yarn utilizes the stretch back property of the core yarn, and the fabric is dyed in the dyeing process. It does not shrink, and although fabrics made from this yarn have a high density when contracted, they expand and contract when worn, making it extremely difficult to use water repellent fabrics for binding.

The preferred characteristics of the core yarn used in the present invention include (1) the number of filaments of 24 or more in order to effectively intertwine with the multifilament for floating yarn; (2) the fabric can be shrunk in the normal dyeing process, and the density of the fabric can be increased. In order to further increase the boiling water shrinkage rate, it is preferably 10% or more, and (3) the cutting elongation rate is preferably 60% or less, since if it is too high, the fabric structure will shift when worn.

On the other hand, the preferable characteristics of the floating filament that forms finely uneven loops are (1) ultra-fine multifilaments of 1.2 d/f or less to form dense uneven loops, and (2) effective interaction with core multifilaments. (3) The elongation is preferably 60% or more in order to easily wind around the core yarn and cause a difference in yarn length during false twisting and crimping.

In general, preferable conditions for the method of the present invention include (1)
Increase the supply of multifilament for floating yarn by 2 to 10% compared to the amount of multifilament for core yarn, and actively give a difference in yarn length between the two (2) Multifilament for core yarn and floating yarn. The number of entanglements with multifilament for yarn is 50/
(3) The number of false twists is such that the twist index (α) is O, a
The number of false twists (T/M) = (□) etc. should be O~1.0.

(Effects of the present invention) The composite yarn obtained by the present invention has a core/float structure,
The floating yarn forms a finely uneven loop, and the multifilaments that make up the core and the multifilaments that make up the floating yarn are intertwined, and the looped floating yarn restrains the core yarn multifilament when it contracts. Since the core yarn is not heated, the surface of the fabric is covered with finely textured loops, and the density of the fabric is increased, resulting in a water-repellent effect. It is possible to obtain high-quality fabrics.

The boiling water shrinkage rate and degree of entanglement in the present invention refer to values measured according to JIS Li013 7.15(1) hot water shrinkage rate and 7.13 degree of entanglement, respectively. In addition, the cover factor is warp density (book/inji) x F "thread - 71 three-nil ten latitude density (
Book/Inge) XJ - First grandchild 7 Neil.

(Example) The present invention will be explained below with reference to Examples.

Example 1 Length Iron 6 drawn yarn 47 de with intrinsic viscosity [ηF=1.56
/34fil (cutting elongation 38%, boiling water shrinkage 12%
), nylon 6 44d with intrinsic viscosity [77] = 1.02
e/40f i 1 (cutting elongation 62%, boiling water shrinkage 1
0%) and a feed speed of 200 m/min and 212 a/min using an entangling nozzle (X-34 type nozzle manufactured by DuPont).
The yarn was then processed under a pressure of 2 kg/cm2 to obtain a composite yarn with a degree of entanglement of 180 knots/cm2, and immediately introduced into a 3-axis friction false twisting unit (Positorque manufactured by Rita Scruggs) with a degree of entanglement of 280 kg/cm2.
A twist of 0 twists/m was applied, and the material was untwisted and wound. As a result, a composite textured yarn with a two-layer structure in which the high elongation yarn (8) was mainly arranged in the outer layer of the yarn and had fine uneven loops was obtained. (Thread length difference: 16%) Using this thread, warp density 128.3 threads/2.54 Cm,
A plain weave fabric with a weft density of 96.0 threads/2.54 cm with a cover factor of 2390 was created and refined using conventional methods.

Relaxation, drying, presetting, dyeing, drying, water repellent treatment with fluororesin, and calendering were performed. The cover factor of the obtained fabric was about 2600, and the surface of the fabric was covered with fine uneven loops, and the water repellency was excellent.

In this example, the yarn heat-set at 190''C during false twisting was obtained into a fabric under the same conditions as above, and the dyed fabric was covered with fine uneven loops on the surface of the fabric. The water repellency was low, about 2100, and the water repellency was slightly inferior.

Example 2 Polyethylene terephthalate drawn yarn with intrinsic viscosity [η] = 0.72 50de/24f i I (cutting elongation 3
2%, boiling water shrinkage rate 12%) and constrained spun yarn 64de/
114 (cutting elongation 84%, boiling water shrinkage 7%) was treated under the same conditions as Example 1 (however, the temperature during false twisting was set to 130°C, which is below the temperature at which the drawn yarn is heat set). , density 123/2.54. To create a plain woven fabric with a weft density of 70 threads/2.54, the cover factor is 2070. The cover factor is 2400 even though it is dyed according to the conventional method, and the surface of the fabric is covered with fine uneven loops, making it water repellent. was extremely good.

Claims (1)

[Claims] After the multifilament yarn that will become the core yarn and the ultra-fine multifilament with high elongation are interlaced and intertwined, the multifilament yarn that will become the core yarn is temporarily heated at a temperature that does not substantially change the boiling water shrinkage rate of the multifilament yarn that will become the core yarn. A method for producing a composite yarn characterized by performing twisting and crimp processing.