JPH09111564A - Polyester combined filament yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a combined filament yarn capable of providing a fabric excellent in swelling feeling, flexibility and drape and proper in tension and stiffness, having a natural fiber-like handle. SOLUTION: This combined filament yarn comprises a thick and thin yarn A obtained by drawing an undrawn highly orientated yarn having 20-40% structure integrity parameter (ε0.2 ) in a draw ratio equal to or lower than a natural draw ratio and subjecting the undrawn highly orientated yarn to >=5% heat treatment under relaxation at a temperature equal to or higher than the glass transition temperature of the undrawn highly orientated yarn +10 deg.C and a multifilament yarn B. The physical properties of the thick and thin yarn A and the multifilament B satisfy the following characteristics. 25>=Sa>=5 (Sa: shrinkage percentage in boiling water (%) of the thick and thin yarn A), Sb>=5 (Sb: shrinkage percentage in boiling water (%) of the multifilament yarn B) IMa<=40 (IMa: initial modulus (g/d) of the thick and thin yarn A) and IMb>=80 (IMb: initial modulus (g/d) of the multifilament B).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester mixed yarn which, when knitted or knitted, can obtain a fabric having an excellent bulging feeling, flexibility, drapeability and a natural fiber-like texture for clothing. is there.

[0002]

2. Description of the Related Art Polyester fibers are widely used for clothing. As polyester fibers for clothing, multifilaments having different heat shrinkage ratios are mixed in order to develop a swelling typified by a silky texture. Many proposals have been made for so-called heterogeneous shrinkage mixed yarns.

[0003] Polyester fibers have the drawback of being inferior in performance such as flexibility and drapability due to their strong molecular structure. Therefore, they are disclosed in Japanese Patent Publication No. 3-42334, Japanese Patent Publication No. 4-1097, and Japanese Patent Publication No. 4-97. No. 18051 discloses that a yarn having a shrinkage rate of boiling water of close to 0% or a heat stretchable yarn having a shrinkage rate of less than 0% is used as a low shrinkage yarn, so that the fabric has flexibility, drapeability, and appropriate elasticity. , A heterogeneous shrinkage mixed filament yarn capable of expressing stiffness has been proposed.

However, these different shrinkage mixed yarns are
Since the entire yarn is flat, unevenness in thickness and subtle dyeing unevenness do not occur, and the fabric obtained by weaving and knitting the yarn does not have a natural fiber-like texture.

[0005]

The present invention solves the above problems and, when knitted and knitted, has an excellent bulging feeling, flexibility, drapeability and appropriate elasticity and elasticity for clothing, and It is a technical subject to provide a polyester mixed yarn capable of obtaining a fabric having a natural fiber-like texture.

[0006]

The present inventors have arrived at the present invention as a result of intensive studies to solve the above problems. That is, the present invention provides a structural integrity parameter (ε
_0.2 ) 20 to 40% polyester highly oriented undrawn yarn is drawn at a draw ratio of not more than the natural draw ratio, and then the glass transition temperature of the highly oriented undrawn yarn (hereinafter referred to as Tg) + 10 ° C or more % Of the thick and thin yarn A and the multi-filament B obtained by performing a relaxation heat treatment of 100% or more, and the physical properties of the thick and thin yarn A and the multi-filament B satisfy the following characteristics. The gist of the present invention is the characteristic polyester mixed yarn. 25 ≧ Sa ≧ 5 Sa: boiling water shrinkage (%) of thick and thin yarn A Sb ≧ 5 Sb: boiling water shrinkage (%) of multifilament B IMa ≦ 40 IMa: initial elastic modulus of thick and thin yarn A (g) / D) IMb ≧ 80 IMb: initial elastic modulus of multifilament B (g / d)

[0007] The structural integrity parameter (ε _0.2 ) referred to in the present invention represents the elongation when the yarn is treated in boiling water by applying a load, and is measured by the following method. . Using an ε meter manufactured by Toyobo Engineering Co., Ltd., a highly oriented undrawn yarn having a length of 20 cm is applied with a load of 0.2 g / d and treated in boiling water (about 99 ° C.) for 2 minutes. The length of the yarn before and after the treatment is measured and calculated by the following formula. ε _0.2 (%) = [(L ₁ −L ₀ ) / L ₀ ] × 100 where L ₀ : length before treatment (20 cm) L ₁ : length after treatment

The shrinkage rate of boiling water was determined by applying a load of 1/30 (g / d) to the yarn that had been decapsulated 20 times with a measuring machine and measuring the length (L ₂ ) of the thread. After being treated for 30 minutes with a load of 1/30 (g / d), the length (L ₃ ) is obtained and calculated by the following formula. Boiling water shrinkage = _{[(L 2 -L 3) / L} 2 ] × 100

The initial elastic modulus was Tensilon UTM-4-100 type manufactured by Oriental Co., Ltd., the sample length was 10 cm, and the tensile speed was 10 cm.
The tensile test is performed for 1 minute, and the tensile strength is obtained from the obtained strength and elongation curve.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. In the present invention, as the polyester, those having ethylene terephthalate as a main repeating unit are preferably used, and in addition to polyethylene terephthalate,
As long as the effect of the present invention is not impaired, it may be a copolymer of acid components such as isophthalic acid, adipic acid, sebacic acid and the like, alcohol components such as 1,4-butanediol and 1,6-hexanediol, In addition, stabilizers, fluorescent agents, pigments,
It may be one to which a reinforcing agent or the like is added.

First of all, the thick and thin yarn A, which is one of the yarns constituting the mixed fiber of the present invention, is a polyester highly oriented undrawn yarn having a structural integrity parameter (ε _0.2 ) of 20 to 40%. It is necessary that the highly oriented unstretched yarn is stretched at a draw ratio of not more than the draw ratio and then subjected to a relaxation heat treatment of 5% or more at a temperature of Tg + 10 ° C. or more.

The structural integrity parameter (ε _0.2 ) of the feed yarn for thick and thin yarn A must be 20-40%. The structural integrity parameter is an index that comprehensively represents the crystallinity and orientation of the fiber,
When this value exceeds 40% and becomes large, the undrawn yarn has low crystallinity and low orientation, and even if relaxation heat treatment is applied, the orientation and crystallinity cannot be sufficiently increased, and the boiling water shrinkage rate. May not be reduced, the thickness unevenness may become too large when stretched at a stretch ratio not higher than the natural stretch ratio, or the yarn may become brittle and may have thread breakage during processing. On the other hand, if it is less than 20%, the yarn will have high orientation and high crystallinity,
Thickness unevenness is less likely to appear when stretched, and the woven or knitted fabric does not have a natural fiber-like texture or flexibility.

In order to obtain a polyester highly oriented undrawn yarn having a structural integrity parameter (ε _0.2 ) within the above range, the melt viscosity of the polyester, the spinning speed, the heat treatment conditions of the undrawn yarn, etc. are properly selected. The polyester may be melt-spun, but the method of selecting the spinning speed is the easiest and is preferable, and the spinning speed may be approximately 2700 to 4200 m / min.

Then, the highly oriented undrawn yarn for thick and thin yarn A is drawn at a draw ratio of not more than a natural draw ratio and then subjected to a relaxation heat treatment of 5% or more at a temperature of Tg + 10 ° C. or more to give a thick Obtain Andshin Yarn A. When the drawing is carried out at a draw ratio exceeding the natural draw ratio, a yarn having no thickness unevenness is obtained, and the fabric obtained by weaving and knitting the yarn becomes poor in natural fiber-like texture and swelling feeling.
The stretching temperature is not particularly limited, but 25 ° C or higher,
It is preferably Tg or less.

If the relaxation heat treatment temperature is lower than Tg + 10 ° C., the structure inside the fiber cannot be changed, and the boiling water shrinkage Sa of the obtained yarn exceeds 25%. The upper limit of the relaxation heat treatment temperature is not particularly limited, but it is preferably about Tg + 100 ° C. Tg + 100
When the temperature exceeds ℃, the highly oriented undrawn yarn is heat-treated at a high temperature, so the yarn is cut by the heat treatment and the boiling water shrinkage Sa is 5%.
And the resulting fabric tends to have an insufficient swelling feeling.

Further, the relaxation rate needs to be 5% or more. If the relaxation rate is less than 5%, the yarn will have a small thickness unevenness, and thus the fabric obtained using this yarn will lack natural fiber-like texture and swelling feeling. The upper limit of the relaxation rate is not particularly limited, but is generally 20.
%. If the relaxation rate exceeds 20%, it will be difficult to shrink on the heater, depending on the heat treatment temperature, and the operability tends to deteriorate.

The boiling water shrinkage Sa of the thick and thin yarn A must be 5 to 25%. When Sa is less than 5%, the winding shape is deteriorated, the takeout is likely to occur at the time of unwinding, and the obtained mixed fiber yarn has loops. In addition, since the shrinkability is small, the fabric obtained by weaving and knitting the mixed fiber obtained has a poor swelling feeling. On the other hand, S
When a exceeds 25%, the shrinkage becomes too large, and the fabric obtained by weaving and knitting the mixed yarn has poor flexibility.

The multifilament B forming the mixed yarn with the thick and thin yarn A must have a boiling water shrinkage Sb of 5% or more. When Sb is less than 5%, the shrinkability is small, and thus the resulting fabric made by knitting and knitting has a poor swelling feeling, and like the sick and thin yarn A, is easily taken out during unwinding. The obtained mixed yarn has loops. S
Although the upper limit of b is not particularly limited, it is preferably about 30%, and if it exceeds this value, the shrinkage becomes too large, and the fabric obtained by weaving and knitting this mixed yarn has a softness. It tends to be scarce.

Next, it is necessary to set the initial elastic modulus IMa of the thick and thin yarn A to 40 g / d or less and the initial elastic modulus IMb of the multifilament B to 80 g / d or more. When the initial elastic modulus IMa of the sick and thin yarn A exceeds 40 g / d, this mixed yarn will only give a fabric having poor flexibility when knitted or woven. Further, when the initial elastic modulus IMb of the multifilament B is less than 80 g / d, the mixed yarn can obtain only a fabric which is poor in swelling feeling, elasticity and elasticity when knitted and woven.

In order to set the initial elastic moduli IMa and IMb within the range of the present invention, the tension and the draw ratio during heat treatment or drawing of the undrawn yarn may be adjusted. That is, in order to set the initial elastic modulus IMa of the thick and thin yarn A to 40 g / d or less, stretching and heat treatment may be performed with a tension of 1.2 g / d or less, and the initial elastic modulus IMb of the multifilament B is 80 g / d.
To obtain d or more, drawing may be performed at a draw ratio of 1.2 times or more the natural draw ratio of the undrawn yarn.

In the mixed yarn of the present invention, if the boiling water shrinkage Sa of the thick and thin yarn A and the boiling water shrinkage Sb of the multifilament B are within the above ranges, whichever has a higher shrinkage. Good, but the difference between the two is 0.5-13%
It is preferable to set the degree. Further, the mixing ratio of the thick and thin yarn A and the multifilament B in the mixed fiber is not particularly limited, but it is preferable that the weight ratio is 2: 1 to 1: 2.

Next, an example of the method for producing the polyester mixed yarn of the present invention will be described. First, an example of a method for producing the thick and thin yarn A will be described with reference to FIG. The highly oriented undrawn yarn Y obtained by melt spinning is drawn between the first roller 1 and the second roller 2 at a draw ratio not higher than the natural draw ratio, and then Tg +
After the heat treatment is performed on the contact-type heat treatment heater 3 at 10 ° C. at a relaxation rate of 5% or more, the yarn is wound around the pan 5 through the take-up roller 4.

Further, in order to produce the multifilament B, a conventional spinning and drawing may be carried out, and the spinning speed is 1000 to 1500.
The undrawn yarn obtained by spinning at m / min is drawn at a drawing speed of 400-80.
Stretching at 0 m / min, stretching ratio 2.6-3.5, temperature 100-100
Heat it at 0 ° C and wind it. Examples of the method of mixing the wound thick and thin yarn A and the multifilament B include a method of stretching and mixing, aligning, and performing a fluid entanglement treatment.

[0024]

Next, the present invention will be specifically described with reference to examples. Each evaluation in the examples was performed by the following methods. (a) Intrinsic viscosity An equal weight mixture of phenol and ethane tetrachloride was used as a solvent and measured at 20 ° C. (b) Fineness The fineness was calculated by winding the fiber 400 times around a measuring machine with an outer circumference of 1.125 m and measuring the weight. (c) Quality (loop, unwinding property) Visual observation of the loop occurrence status of the mixed yarn (1 kg) wound around the parn and the unwinding property (whether or not it is taken out) when unwinding at 500 m / min. Evaluation was made in three grades of ◯, Δ, and ×. Loop ○: No loop △: Some loops ×: Many loops unwinding ○: No take-out or yarn breakage occurs. Δ: Takeout and yarn breakage sometimes occur. X: Take-out and yarn breakage frequently occur. (d) Texture (swelling, firmness, elasticity, flexibility) After knitting the mixed yarn and dyeing it, the swelling and firmness, elasticity, flexibility are evaluated by touch on three grades, ○, △, ×. did. ○: Good △: Normal ×: Poor (e) Dyeing unevenness After knitting the mixed fiber yarn and dyeing it under the following conditions, visually observing whether or not there is a delicate dyeing unevenness like natural fiber, The evaluation was made in three grades of ◯, Δ and ×. (Dyeing conditions) Dye-disperse dye (Terasil Navy Blue SGL, manufactured by Ciba-Geigy Japan) 1.0% owf Auxiliary-dispersant (Disper TL, manufactured by Meisei Chemical Co., Ltd.) 2 g / liter Formic acid 0.1 g / liter Ammonium sulfate 2 g / liter Bath ratio-1 : 50 Dyeing temperature −100 ° C. Dyeing time −60 minutes ○: Natural fiber-like spots occur. Δ: Spots similar to those of natural fiber occur. X: No natural fiber-like spots are formed.

Examples 1 to 4 and Comparative Examples 1 to 7 Polyethylene terephthalate chips having an intrinsic viscosity [η] of 0.69 and a Tg of 72 ° C. were dried by a usual method, and then a spinneret having 36 nozzles having a triangular cross section was used. An undrawn yarn (for thick and thin yarn A) having various structural integrity parameters (ε _0.2 ) and a natural draw ratio shown in Table 1 was spun at a spinning temperature of 295 ° C while changing the spinning speed as shown in Table 1. Of the supplied yarn). At this time, the discharge amount was changed according to the spinning speed, and the fineness of the obtained undrawn yarn was adjusted to 75 d. The obtained unstretched yarn was stretched and relaxed by the stretching machine shown in FIG. 1 under the conditions shown in Table 2. Table 2 shows boiling water shrinkage Sa and initial elastic modulus IMa of the obtained thick and thin yarn A.

[0026]

[Table 1]

[0027]

[Table 2]

Next, a polyethylene terephthalate chip having an intrinsic viscosity [η] of 0.69 and a Tg of 72 ° C. was dried by a usual method and then spun at a spinning temperature of 295 ° C. using a spinneret having 12 nozzles with a round cross section. It was wound up at a speed of 1300 m / min.
At that time, the discharge amount was adjusted so that the fineness after stretching was 50 d. This undrawn yarn was drawn under the drawing conditions shown in Table 3 at a drawing speed of 700 m / min. Table 3 shows the boiling water shrinkage ratio Sb and the initial elastic modulus IMb of the obtained multifilament B.

[0029]

[Table 3]

Various thick and thin yarns A (No. 1
~ 8) and multifilament B (No. 1-4) are entangled
The fibers were mixed at 45 to 55 pieces / m, and wound on a pan. Table 4 shows the Nos. Of the thick and thin yarns A and B used, the quality of the obtained mixed fiber, and the evaluation results of the texture of the tubular knitted fabric.

[0031]

[Table 4]

The mixed filament yarns obtained in Examples 1 to 4 have good unwinding property, and the tubular knitted fabric has a feeling of swelling, flexibility, firmness,
It had excellent elasticity and a natural fiber-like texture. On the other hand, in Comparative Example 1, the structural integrity parameter (ε _0.2 ) was too high, and in Comparative Example 2, the relaxation heat treatment temperature was too low, so that the boiling water shrinkage rate of both the thick and thin yarn A was too high. The fabric obtained by weaving and weaving the fine yarn was poor in swelling feeling and flexibility. In Comparative Example 3, the structural integrity parameter (ε _0.2 ) was too low, and in Comparative Example 5, the relaxation rate at the relaxation heat treatment was too low. Therefore, the boiling water shrinkage rate of the thick and thin yarn A was low and the initial elastic modulus was low. When the knitted yarn was too high, the unwound yarn obtained was inferior in unwinding property, loops were formed, and when knitted, the fabric was inferior in swelling and flexibility and was inferior in natural fiber-like texture. Since Comparative Example 4 was drawn at a higher draw ratio than the natural draw ratio, it did not become thick and thin yarn, and the mixed fiber yarn obtained from this yarn was inferior in flexibility when knitted and was inferior in natural fiber-like texture. Became. In Comparative Example 6, since the boiling water shrinkage of the multifilament B was too low, the obtained mixed yarn had loops and unwindability was poor, and the woven and knitted fabric had a feeling of swelling, firmness, stiffness and the like. It was inferior. In Comparative Example 7, since the initial elastic modulus of the multifilament B was too low, when it was knitted or woven, the resulting fabric had poor swelling, elasticity and elasticity.

[0033]

EFFECTS OF THE INVENTION The polyester blended yarn of the present invention, when knitted or woven, has an excellent swelling feeling, flexibility and appropriate elasticity and elasticity for clothing, and a fabric having a natural fiber-like texture can be obtained. Becomes

[Brief description of the drawings]

FIG. 1 is a schematic process drawing showing an embodiment for producing thick and thin yarn A in the present invention.

[Explanation of symbols]

 1 1st roller 2 2nd roller 3 Contact-type heat treatment heater 4 Take-up roller 5 Pane

Claims (1)

[Claims] 1. A structural integrity parameter (ε _0.2 ) of 20 to
Thick obtained by stretching 40% polyester highly oriented undrawn yarn at a draw ratio not higher than the natural draw ratio, and then subjecting the highly oriented undrawn yarn to a glass transition temperature + 10 ° C or more and a relaxation heat treatment of 5% or more. A polyester blended yarn composed of and thin yarn A and multifilament B, wherein the physical properties of thick and thin yarn A and multifilament B satisfy the following characteristics. 25 ≧ Sa ≧ 5 Sa: boiling water shrinkage (%) of thick and thin yarn A Sb ≧ 5 Sb: boiling water shrinkage (%) of multifilament B IMa ≦ 40 IMa: initial elastic modulus of thick and thin yarn A (g) / D) IMb ≧ 80 IMb: initial elastic modulus of multifilament B (g / d)