JPS5847481B2 - Manufacturing method of spun yarn - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for manufacturing spun yarn.

More specifically, a tow-like fiber is cut into a sliver-like material, and when forming a yarn using this fiber, a large number of materials with different heat shrinkability are mixed in the cut sliver, and this is made into a yarn. The present invention relates to a method for producing spun yarn that exhibits excellent bulk and texture when made into a product.

In particular, the present invention relates to a method for producing spun yarn that has water absorption and moisture absorption performance and can exhibit a unique texture and appearance when made into a fabric by applying water-absorbing fibers as the tow-like fibers.

Conventionally, various methods have been known for spinning tow-like materials, and the parlock method, turbo method, sorter method, etc. have been widely used.

According to these methods, slivers with stable cutting properties and heat shrinkage performance can be obtained. Therefore, as a method for producing acrylic bulky spun yarns, yarn structures composed of two components, a high shrinkage component and a low shrinkage component, are particularly recommended. Mainly manufactured.

However, when the ordinary spun yarn obtained by these methods is heat-treated as a yarn, the high-shrinkage component protrudes from the core and the low-shrinkage component from the surface layer, resulting in an extremely clear two-layered yarn structure, resulting in a bulky 4. Although it has excellent durability, when made into a fabric, the knitted surface is not neat, and the tension and waist feel are poor, resulting in a loose feel.

Furthermore, when a yarn is formed using only low-shrinkage components, only a yarn with a low bulk and high performance and a hard texture can be obtained.

In view of these disadvantages of conventional spun yarns produced by Ken-kiri spinning, the present inventors conducted intensive research on the formation of new yarn structures, and as a result, they arrived at the method for producing spun yarns of the present invention.

The present invention consists of the following constituent elements.

That is, the average single fiber strength of the tow-like material is 4. A tow-like synthetic fiber with oP/d or less and a distribution of single fiber breaking elongation of 25% or more with a coefficient of variation C■ is drawn, and the drawing causes a large number of partially broken fibers to be generated, followed by cutting. It is characterized by forming a sliver-like material by cutting the material, which is then blended with other materials containing 100% or at least 30% by weight to form a yarn material, and then heat-treated. be.

The present invention will be explained in more detail below.

The present invention skillfully combines both the physical properties of the raw tow-like fibers and the cutting method, thereby imparting diversity to the heat shrinkability of the fibers forming the sliver formed by cutting the fibers, thereby creating an unprecedented novelty. It forms a bulky spun yarn.

Here, the coefficient of variation Cv value indicates the degree of dispersion around the average value μ, and is a relative amount indicating how much it varies with respect to μ, and is calculated by the following formula.

σ is the standard deviation, which is calculated from the data xi and the average value μ.As for the cutting method, cutting may be performed only by stretching between the nip rollers, or a play cover or the like may be used as an auxiliary means.

The present invention particularly focuses on the single fiber strength as the physical property of the supplied fiber. O
f/d or less, preferably in the range of 2.5 to 4.0 g/d, and use a substrate that causes large fluctuations in the elongation at break. A sliver-like material made of single fibers having different shrinkage characteristics is obtained by partially cutting the fibers by heating, and then cutting the fibers by cutting.

The number of fibers cut in the drawing zone is preferably 3 to 40% of the total number of fibers.

The sliver made of single fibers with different shrinkage properties obtained as described above is either used 100% as it is to make yarn, or is blended with other materials to make yarn, and then heat-treated. .

When blending, it is preferable that the above-mentioned fibers be contained in an amount of at least 30% by weight; if the blending ratio is lower than this, the effects of the present invention will be reduced.

Regarding the method for obtaining spun yarn in the above embodiment, it is preferable to use acrylic water-absorbing fibers as the fiber material.

In particular, when the water-absorbing fiber is composed of a microporous core layer and a relatively dense skin layer, the yarn has extremely high water-absorbing properties and has excellent properties such as anti-pilling properties and texture. You can obtain the article.

FIG. 1 is a schematic side view showing an example of a cutting machine used in the present invention, in which 1 and 1' are supply tows, 2 and 3 are supply rollers, 4, 5, 6 and 7, 8, Reference numerals 9 are gripping rollers, and the section between the two constitutes a stretching region, and 10 and 11 are heaters.

The sections 16 and 170 of the gripping rollers 7, 8, and 9 constitute a cutting area, and the sections 14 and 15 are play covers for auxiliary cutting, which are provided as required.

18 is a feed roller, 19 is a crimper, and hoods 12 and 13 are suction devices for removing short fiber flies in the stretching and cutting areas.

In the above structure, the present invention provides that the supplied fiber tow 1 has an average single fiber strength of 4. or/d or less, and the numerical distribution of elongation at break is such that the coefficient of variation CV is 25% or more,
Fractures occur in the bicomponent fibers when subjected to heated stretching in the stretching zone.

As a result, the fiber bundles supplied to the subsequent cutting areas include fibers that have already been cut and fibers that are in a state immediately before being cut.

These are then subjected to stretching at a constant rate and are cut into various states with different heat shrinkability depending on the degree of elongation at break.

Particularly, among these, the constituent fibers that have already been broken in the drawing region produce a portion that is hardly broken, resulting in a fiber bundle with low shrinkage ability.

Table 1 shows samples with different single fiber strengths of acrylic fibers and different CV values of elongation at break.
The results of checking the state of cutting of the constituent single fibers in relation to this and the stretching ratio at the stretching section in the apparatus of the embodiment shown in FIG. 1 are shown.

Here, the single fiber strength was changed by appropriately generating void-like portions in the fibers.

The supplied tow was 500,000 D, and the single yarn denier was 3D.

As is clear from Table 1, even at a low draw ratio, if the physical properties of the supplied fibers are specified, a sufficient amount of broken fibers will occur in the drawing section.

In particular, the single yarn strength is 4. o? /d or less, stable generation can be achieved.

On the other hand, if it is less than 2.59/d, excessive breakage occurs, which tends to cause fly-like fibers and problems with wrapping around the gripping roller, which is somewhat undesirable in terms of operation.

Next, Table 2 shows the results of checking the heat shrinkage characteristics according to the draw ratio using the fiber material (L-7) listed in Table 1.

Samples with no breakage after stretching at various stretching ratios were picked up and their shrinkage rates were measured.

As is clear from Table 2, fiber bundles with different heat shrinkage abilities can be obtained depending on the stretching ratio, and the aggregates of fiber bundles broken in the stretching region or cutting region range from those with extremely low shrinkage to those with extremely low shrinkage. It is possible to have a mixture of a wide range of shrinkage characteristics, including those with high shrinkage.

The sliver-like fiber aggregate obtained by the present invention can be made to have good various shrinkage abilities by being stretched at the above-mentioned stretching ratio of 1.07 to 1.4 times and then cut. By forming these into a yarn and heat-treating the yarn, a bulky yarn with a multilayer structure can be obtained.

According to the knowledge of the present inventors, the optimum stretching ratio range seems to be 1.15 to 1.40 times, as is clear from Table 1.

The appearance of the yarn is different from conventional bulky yarns, and is not clearly separated into two layers.

It is firm to the touch, retains bulk, and has firmness and firmness.

In addition, it is preferable that the expansion magnification in the cutting area is set to about 3.0 to 4.5 times.

Example A copolymer of 95 mol % of an acrylonitrile polymer and 48 mol % of a copolymerizable vinyl monomer and 0.2 mol % of an acidic group-containing vinyl monomer. A microporous acrylic fiber having water absorbing properties and having the following physical properties, consisting of an acrylic polymer composed of a polymer and a void stabilizer, was used and supplied to the sliver forming apparatus shown in FIG.

The detailed conditions are as follows. Single fiber denier: 2d 〃 Strength: 3.2S'/d 〃 Elongation: 21% 〃 CV value of elongation: 28% Water retention rate of tow-like fiber: 13% 〃 Total denier: 500,000 D Stretching and cutting Conditions Stretching ratio: 1.35x Cutting ratio: Flare covers 14, 15 and front rollers 16, 17
Section: 1.37 times breaker bars 14, 15 and feed rollers 7, 8, 9 sections 2 3.1 times Short fibers constituting the sliver-like material after cutting were picked up and their boiling water shrinkage rates were measured. The results showed various shrinkage rates ranging from about 3% to 27%.

Using this sliver, a yarn count of 1/48 Nm (metric type) was spun, heat treated, and then used to make a knitted fabric (double jersey, basis weight 2 soy/m).

The product features excellent bulkiness, firmness, elasticity, and repulsion, as well as a lightweight feel.

It has water-absorbing properties, so it has the same functionality as conventional cotton yarn fabrics, but it also has a dry surface even when wet, and has a unique touch, making it more comfortable to wear than cotton yarn fabrics. be.

The water retention rate is determined by the ASTM method (American Society
tg for Testing and Materia
ls, P A R T 3 3 page 467 (1
974)) was 10.2%.

In addition, the anti-pilling performance was good as grade 4 by ICI method (5 hours).

The yarn obtained by the present invention is particularly suitable for the underwear field, women's knitwear, bedding field (nightwear, sheets, etc.), and household use (roll towels, pass towels, etc.).

[Brief explanation of drawings]

FIG. 1 is a side view showing one embodiment of the sliver manufacturing method used in the present invention. 1, 1': Supply tow, 2, 3: Supply roller, 4, 5, 6
, 7, 8, 9, 16, 17: gripping roller, 10, 11:
Heater, 12, 13: Hood, 14, 15: Breaker bar, 18: Feed roller, 19: Crimper, 20:
Sliver.

Claims (1)

[Claims] 1. Average single fiber strength is 4. By stretching a tow-like composite fiber that is less than OS'/d and whose single fiber elongation at break has a coefficient of variation CV of 25% or more, some of the fibers are broken, and then a part of the fibers is broken in a breaking zone. 1. A method for producing spun yarn, which comprises forming into a sliver, then forming a yarn containing at least 30% by weight of the fibers, and heat-treating the yarn. 2. The method for producing spun yarn according to claim 1, wherein the stretching ratio is 1.07 to 1.40 times. 3. Production of spun yarn according to claim 1 or 2, characterized in that the synthetic fiber is a water-absorbing acrylic fiber consisting of a microporous core layer and a relatively dense skin layer. Method.