JP3059211B2 - Method for producing composite crimped yarn - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing a composite crimped yarn having a spotty appearance and feeling like a spun wool yarn.

(Prior art) False twisted crimped yarn obtained by false twisting polyester yarn is extremely bulky in the state of yarn, that is, under micro tension close to no tension. ,
There is a disadvantage that most of the bulkiness is lost.

In addition, two polyester multifilament yarns having different birefringence and elongation are used as supply yarns, and these are aligned and false twisted, and a high elongation multifilament yarn is used as an outer layer and a low elongation multifilament yarn is used. There is also known a method for producing a crimped yarn having a two-layer structure positioned as an inner layer.
When the crimped yarn obtained by this method is subjected to tension during weaving and knitting, most of the tension is applied to the core yarn and almost no tension is applied to the sheath yarn. This was an effective processing method to obtain a feeling of swelling.

However, this crimped yarn has a relatively smooth surface with little unevenness, and emphasizes the waxy feeling of the synthetic fiber. Was desired.

In order to solve the above-mentioned drawbacks, the present inventors have disclosed in
In Japanese Unexamined Patent Publication No. 58-98400, a polyester heat-treated unoriented yarn is subjected to a relaxation heat treatment at an overfeed rate of 20% or more.
Next, a method of performing simultaneous stretching and false twisting was proposed. Since the processed yarn obtained by this method has a bulky crimp portion and a tightening bunched portion, it is possible to form a fabric while maintaining the bulkiness. Since there is little change between the constituent single filaments, the appearance and texture of spun wool yarn are far from good, and further improvement has been desired.

(Problems to be Solved by the Invention) The present invention eliminates the above-mentioned drawbacks of the conventional crimped yarn, is excellent in bulkiness, is rich in natural spots, and has no delicate feeling of synthetic fibers. An object of the present invention is to provide a method for producing a composite crimped yarn having a shiny taste.

(Means for Solving the Problems) That is, the present invention relates to a method of preparing a plurality of highly oriented undrawn yarns having different birefringence (Δn) of at least 5 × 10 ⁻³ or more by drawing a plurality of unoriented polyester fibers at an overfeed rate of 5% or more. The yarn is heat-relaxed to give unevenness in thickness, and a difference in shrinkage of the undrawn yarn causes a difference in yarn length, thereby forming a loop or a slack yarn. The gist of the present invention is to provide a method for producing a composite crimped yarn, which is characterized by imparting curls.

 Hereinafter, the present invention will be described in detail.

First, in the present invention, the birefringence (Δn) is at least 5
A plurality of highly oriented polyester unoriented yarns differing by ^10-3 or more are aligned and subjected to relaxation heat treatment at an overfeed rate of 5% or more.

The birefringence of the yarn supplied to the relaxation heat treatment is 20 × 10 ^-3 to 80 × 10
^-3 is preferable, and when the birefringence is less than 20 × 10 ^-3 , the yarn is liable to be heat-brittle. On the other hand, if it exceeds 80 × 10 ^-3 , it cannot be sufficiently shrunk by relaxation heat treatment.

The difference in birefringence must be 5 × 10 ⁻³ or more between a plurality of highly oriented polyester undrawn yarns to be aligned as described above.
By making the birefringence different by at least 5 × 10 ^{-3, a} difference in shrinkage is provided between the two types of highly oriented undrawn yarns, and a yarn length difference is given to the yarn after the relaxation heat treatment, and each highly oriented undrawn yarn The unevenness of thickness is formed in the longitudinal direction of the single filament constituting the yarn, and the elongation is further increased.

In order to form a sufficient difference in yarn length and uneven thickness between single filaments constituting a plurality of highly oriented undrawn yarns by the relaxation heat treatment, the relaxation heat treatment should be performed at an overfeed rate of 5% or more, preferably 30% or more. If the overfeed rate is less than 5%, the amount of contraction is insufficient, and the above-mentioned plaque cannot be generated.

The set temperature of the heater during the relaxation heat treatment is not particularly limited. However, by setting the set temperature to the melting point or more and setting the heat treatment time to 0.2 seconds or less, the distance between the single filaments and the longitudinal direction of the single filaments can be improved. Can be emphasized, and the effect of the present invention can be further enhanced.

Furthermore, the relaxation heat treatment is preferably performed in a non-contact state. By performing the heat treatment in a non-contact state, it is possible to perform the treatment at a high temperature equal to or higher than the melting point without fusing the yarn.

In the present invention, simultaneous stretching and false-twisting is performed on the highly oriented unoriented yarn of high elongation provided with the yarn length difference and unevenness of the thickness by the above-mentioned relaxation heat treatment. It is preferable to carry out in. By performing the false twisting method, the false twisting can be easily performed without breaking the yarn even if the yarn has a difference in yarn length or uneven thickness as in the present invention.

In the above stretching simultaneous false twisting, the K value (T ₂ / T ₁ ), which is the ratio between the twisting tension (T ₁ ) and the untwisting tension (T ₂ ), is 0.6 to 0.9.
It is preferred that If the K value is less than 0.6, the yarn becomes constricted and the yarn appearance tends to deteriorate. On the other hand, if it exceeds 0.9, fluff is likely to occur on the yarn.

In addition, the draw ratio during simultaneous false twisting is 1.4 times or more.
The temperature of the false twisting process is set to a range where melting does not occur at 150 ° C. or higher, and the degree of crimping to be applied may be adjusted by the number of false twists and the number of disks of the friction false twisting device.

As described above, in the present invention, by unifying the highly oriented undrawn yarns having different birefringences and performing the relaxation heat treatment, the single filament constituting each highly oriented undrawn yarn is given a thickness unevenness, and Due to the difference in shrinkage, the yarn has a difference in yarn length, and the filaments are migrated to each other by this shrinking action.

In normal false twisting, false twist is performed in a state where the filaments are parallel to each other, but in the present invention, filaments having uneven thickness are migrated and entangled with each other, and are formed due to a difference in yarn length. Since the filament bundle with slacks and loops is sent to the false twisting process, the amount of deformation received in this simultaneous false twisting process differs between individual filaments and in the longitudinal direction of the filaments, and there are differences in crimping and physical properties. It becomes a multilayer structure yarn. In this way, it is possible to obtain a composite crimped yarn excellent in spotting and having a crisp taste and swelling.

The crimp spots of the composite crimped yarn obtained in the present invention can also be seen from the fact that the cross-sectional deformation of the constituent filaments differs greatly between the filaments as shown in FIG.

Furthermore, the shiny taste of the composite crimped yarn obtained by the present invention is caused by the above-mentioned unevenness, and the stiffness of the filament is increased because the crystallinity of the polyester highly oriented undrawn yarn is increased by relaxation heat treatment and false twisting is performed. It depends.

The fabric obtained by knitting and weaving the composite crimped yarn obtained in the present invention can impart unevenness of color tone by dyeing with a dye which tends to cause a difference in dyeing so as to emphasize unevenness, but the unevenness is suppressed. When a surface feeling is desired, a dye having excellent levelness may be used, and the surface effect can be changed by selecting the dye.

The yarn used in the present invention is a plurality of highly oriented polyester unoriented yarns having different birefringences of 5 × 10 ^-3 or more, but the fineness is reduced between single filaments constituting the plurality of yarns.
By making the difference of 3.0d or more, it is possible to combine the tightness and waist of the fine fineness filament with the soft feel of the fine fineness filament.

In the present invention, the air entanglement after the simultaneous simultaneous false twisting is not always necessary, but if the air entanglement is performed,
The convergence of the yarn is improved, and the process passability can be improved. Also, due to the migration of filament,
The confounding property in the case of performing the air confounding process is also very good. As the conditions for the air entangling process, the overfeed rate was set to 0 to 10
%, And the pressure is preferably selected within the range of 1 to 7 kg / cm ^{2 according to} the desired degree of confounding.

 Next, an embodiment of the present invention will be described with reference to FIG.

The yarns Y ₁ and Y ₂ drawn from the spools 1 and 1 ′ of the polyester highly oriented undrawn yarn are aligned and passed through the first feed roller 2 and between the first feed roller 2 and the second feed roller 4 by the heater 3. Relaxation heat treatment is applied.

Then, it is stretched between the second feed roller 4 and the first delivery roller 7 and simultaneously heat-set by the heater 5 while being twisted by the friction false twist device 6, passes through the first delivery roller 7 and the second delivery roller 7 and the second delivery roller 7. After being entangled by the air entanglement device 8 between the delivery rollers 9, the second
Package by take-up roller 10 after delivery roller 9
Winded up to 11.

(Operation) As described above, in the present invention, the filaments are migrated by the difference in the amount of shrinkage caused by the birefringence difference received during the relaxation heat treatment, and the filament has a thickness variation and a yarn length difference. Entanglements and loops can be formed.

As described above, since simultaneous drawing and twisting is performed in a state where unevenness in thickness and yarn length difference have occurred, the amount of deformation between individual filaments and in the longitudinal direction of the filaments reaches each other. An existing wool spun yarn-like composite crimped yarn can be obtained.

(Examples) Next, the present invention will be described specifically with reference to examples.

Example 1, Comparative Example 1 Highly oriented undrawn yarn 80d / 18f (Y) having a birefringence (Δn) of 50.2 × 10 ⁻³ obtained by spinning polyethylene terephthalate at high speed
₁ ) Highly oriented undrawn yarn with a birefringence (Δn) of 60.7 × 10 ^-3 obtained by spinning polyethylene terephthalate at high speed
Using 80d / 48f (Y ₂ ) as a supply yarn, processing was performed according to the process shown in FIG. 1 and under the conditions shown in Table 1.

The obtained composite crimped yarn was collected, and the yarns of Example 1 and Comparative Example 1 were compared. The yarn obtained in Example 1 showed that the single filament constituting two yarns was migrated. On the other hand, in the yarn obtained in Comparative Example 1, two yarns were easily separated from each other, and the bundle was inferior.

The obtained composite crimped yarn is used for ordinary loom (L-shaped machine made by Tsuda Koma)
With a warp density of 125 threads / 2.54 cm and a weft density of 90 threads / 2.54 cm
Weaved into a 2/2 twill texture.

When weaving was performed for 5 m above, there was no stop in the yarn of Example 1, but in the yarn of Comparative Example 1, a shift occurred between the two yarns, and the opening of the warp occurred. There was a stop.

Next, the obtained fabric was dyed according to a usual polyester dyeing recipe, and finished as a product.

 Table 2 shows the properties of the obtained composite crimped yarn and woven fabric.

The measurement methods and criteria in the table are as follows.

(1) Yarn length difference Apply a load of 0.1 g / d to the yarn, mark both ends of the sample length of 20 cm, and fix one end. Next, the length of each single filament is measured by dividing the filament from the other end into single filaments, and the difference between the length of each single filament and l is determined based on the length l of the shortest single filament. Divide by l and get 10
It is a value multiplied by 0.

(2) Heat shrinkage rate A 0.1 g / d load is applied to the yarn, the yarn is divided into single filaments, and the sample length of each single filament is 20 cm.
Mark both ends of. Then, after immersing in boiling water for 30 minutes without applying a load, air-drying, apply a load of 0.1 g / d to each single filament, measure the length between the two marks, and before and after boiling water treatment Is 100 times the difference in length divided by the length of single filament before boiling water treatment.

(3) Bundleability of processed yarn ○: Good Δ: Slightly poor ×: Poor (4) Fabric evaluation Judged based on a woven fabric using wool spun yarn.

：: equivalent △: slightly inferior ×: inferior Further, when the tactile sensation and visual inspection of the product were carried out, the product of the yarn of Example 1 had a swelling and shiny feeling even after dyeing due to fine loop-like fluff. It had a texture similar to wool spun yarn.

On the other hand, in the product of the yarn of Comparative Example 1, a large number of yarn deviations were scattered on the surface of the fabric, resulting in a messy surface. In addition, the feeling of touch is strong in wax and wax.
There was no shiny taste like wool spun yarn.

Comparative Example 2 Only the highly oriented undrawn yarn 160d / 48c having a birefringence (Δn) of 57.0 × 10 ⁻³ obtained by spinning polyethylene terephthalate at a high speed was used as a supply yarn, and the process shown in FIG. Processing was carried out under the same conditions as described above. The twisting tension at this time is 58 g,
The untwisting tension was 46 g and the K value was 0.79.

The resulting crimped yarn had little unevenness in thickness and yarn length difference in a single filament, and had little entanglement or loop formation.

The crimped yarn was woven and finished into a fabric, but there was no shiny taste like spun wool yarn.

(Effects of the Invention) According to the present invention, a difference in shrinkage is provided between single filaments constituting a plurality of polyester high-orientation undrawn yarns having different birefringences and in a longitudinal direction of the single filaments, and a difference in yarn length and unevenness in thickness. To give a composite crimped yarn that has crimp unevenness, thickness unevenness, physical property difference, and gives a fabric with the appearance and feeling of using wool spun yarn. Can be.

[Brief description of the drawings]

FIG. 1 is a schematic process diagram showing one embodiment of the present invention, and FIG.
The figure is a schematic sectional view showing one embodiment of the composite crimped yarn obtained by the present invention. Y ₁ , Y ₂ …… Polyester highly oriented undrawn yarn 3,5 …… Heater 6… Friction false twisting device 8 …… Air entanglement device

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-55-45831 (JP, A) JP-A-58-203114 (JP, A) JP-A-2-99626 (JP, A) JP-A Sho 62- 41332 (JP, A) JP-A-61-258036 (JP, A) JP-A-61-194233 (JP, A) JP-A-61-194231 (JP, A) JP-A-1-314716 (JP, A) (58) Field surveyed (Int.Cl. ⁷ , DB name) D02G 1/00-3/48 D02J 1/00-13/00

Claims (1)

(57) [Claims] 1. A plurality of highly oriented polyester unoriented yarns having different birefringences (Δn) of at least 5 × 10 ⁻³ or more are aligned and subjected to relaxation heat treatment at an overfeed rate of 5% or more to give thickness unevenness. At the same time, a difference in the length of the undrawn yarn is caused by the difference in shrinkage of the undrawn yarn, thereby forming a loop or a slack yarn. A method for producing a composite crimped yarn.