JPH07126921A - Filament yarn with polyester part whose bulkiness is latent - Google Patents

Abstract

PURPOSE:To obtain the subject filament yarn having natural fiber-like special touch feel with softness and also having unevennesses in shrinkage and bulkiness in the longer direction manifested through heat treatment. CONSTITUTION:This filament yarn is a conjugate polyester filament consisting of two kinds of polyesters differing in shrinkage characteristics from each other joined in a bimetal manner. The physical properties of the filament yarn satisfy the following relationships: (1) 4<=S100<=25 (S100: boiling water shrinkage rate of the filament yarn (%)); sigmaS>=1 (sigmaS: standard deviation of boiling water shrinkage rate of the filament yarn (%)); and E>=10 (E: shrinkable extension rate (%)).

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyester latent partially bulky filament yarn which develops a special feeling like natural fiber by heat treatment and a method for producing the same.

[0002]

Polyester fibers represented by polyethylene terephthalate fibers are widely used for clothing. Since polyester fibers have characteristics of high orientation and high crystallinity, they are excellent in characteristics such as elasticity and stiffness, but have a drawback that they are inferior in softness to other synthetic fibers. In addition, ordinary polyester fibers do not have the structural and morphological inhomogeneities found in natural fibers, and it is not possible to obtain the unique texture of natural fibers.

As a method for producing a fiber having softness, Japanese Patent Publication No. 63-66923 and Japanese Patent Laid-Open No. 2-293410 disclose a highly oriented undrawn yarn having a birefringence index in a specific range and heat-treated at a high temperature. The method is described. However, since the yarns obtained by these methods are yarns having a uniform shrinkage ratio in the length direction, the yarns are morphologically uniform, and the texture of the yarns is far from that of natural fibers.

In order to impart bulkiness to the yarn,
It is only necessary to form crimps on the fibers.For that purpose, false twisting may be applied to the fibers, or heat treatment may be applied to so-called bimetal type composite yarns in which polymers having different shrinkage properties are joined. Since it has a uniform crimp in the direction, there is a drawback that the change in shape is poor.

Further, as a method for generating morphologically nonuniformity in the length direction of the fiber, an undrawn yarn or a highly oriented undrawn yarn is drawn at a natural draw ratio or less to generate an undrawn portion and a drawn portion. There is a so-called thick and thin yarn manufacturing method. However, the yarn obtained by this method is
Although it has thick and thin spots, it lacks in softness.

As described above, none of the conventional methods can obtain a natural fiber-like yarn having the three elements of softness, bulkiness unevenness due to the presence or absence of fine crimps, and shrinkage unevenness in the longitudinal direction. .

[0007]

DISCLOSURE OF THE INVENTION The present invention solves the above-mentioned problems, and by applying heat treatment, the softness,
To provide a polyester latent partial bulky filament yarn capable of obtaining a natural fiber-like filament having three elements of bulkiness unevenness due to the presence or absence of a fine crimp and contraction unevenness in the length direction, and a method for producing the same. Is.

[0008]

Means for Solving the Problems As a result of intensive studies to solve the above problems, the present inventors have obtained the following findings. In order to impart flexibility to the fiber, a highly oriented undrawn yarn having a structural integrity parameter (ε _0.2 ) in a specific range may be subjected to a relaxation heat treatment at a high temperature. In order to have shrinkage unevenness in the length direction of the fiber, the fiber obtained in (1) is drawn at a low draw ratio, and the drawn part is a highly shrinkable yarn,
The unstretched portion may be a low shrinkage yarn or a heat stretched yarn. In order to express a fine crimp and to express a bulky part and a non-bulky part in the length direction of the fiber, a bimetal type composite fiber in which polymers having different shrinkage properties are joined is drawn, and this yarn is drawn at a low draw ratio, It may be heat-treated.

The present invention has been achieved by such knowledge, and the gist thereof is as follows. (1) A polyester latent partially bulky filament yarn comprising a polyester composite filament in which two kinds of polyesters having different shrinkage properties are joined in a bimetal type, and the physical properties of the yarn satisfy the following formula. 4 ≦ S100 ≦ 25 σS ≧ 1 E ≧ 10 S100: boiling water shrinkage rate of yarn (%) σS: standard deviation of boiling water shrinkage rate of yarn (%) E: expansion / contraction rate of yarn (%) (2) Using a bimetal type composite spinning machine, two types of polyesters having different shrinkage characteristics were melt-spun at a spinning speed of 2500 to 4000 m / min, and the structural integrity parameter (ε _0.2 ) was 15
~ 45% bimetallic polyester composite filament yarn, then preheated at a temperature above the average glass transition temperature (Tg) of the two polyesters, continuously at a temperature above the glass transition temperature (Tg) + 100 ° C After performing a relaxation heat treatment of 1% or more, at a draw ratio equal to or higher than the yield point of the obtained yarn and at a draw ratio at which an unstretched portion and a stretched portion are formed, from the glass transition temperature (Tg) A method for producing a polyester latent partially bulky filament yarn, which comprises drawing at a low temperature.

The boiling water shrinkage rate of the yarn in the present invention is measured with an ε meter manufactured by Toyobo Engineering Co., Ltd. at a measurement temperature of 98 ° C., a sample length of 50 cm, a treatment time of 2 minutes, and a load of treatment of 1/1000 g / d. The average value of 10 measurements was shown. The standard deviation of the boiling water shrinkage of the yarn was determined by measuring the boiling water shrinkage of the yarn continuously every 10 cm in the length direction of the yarn 50 times. (Except for the sample length, it was measured under the same conditions as above.) The elongation / contraction elongation of the yarn was measured by JIS L1077 expansion / contraction elongation measuring method B method using a yarn which was treated with boiling water for 15 minutes in a free state.

The structural integrity parameter (ε _0.2 ) was measured with an ε meter manufactured by Toyobo Engineering Co., Ltd. at a measurement temperature of 99.
℃, sample length 20 cm, processing load 0.2 g / d, processing time 2
It was measured in minutes. The average glass transition temperature (Tg) was measured with a Perkin Elmer DSC-2 differential scanning calorimeter at a temperature rising rate of 10 ° C./min to measure the glass transition temperature (Tg ₁ , Tg ₂ ) of each polyester. and is a value obtained by dividing the sum of Tg ₁ and Tg ₂ at 2. The draw ratio corresponding to the yield point was 10% using the Tensilon UTM-4-100 type manufactured by Orientic.
Strength and elongation were measured at 10 cm / min and a tensile speed of 10 cm / min. The strength-elongation curve was drawn as shown in Fig. 5, the yield point Yp (%) of the strength-elongation curve was calculated, and Yp was divided by 100 to obtain 1 Was added.

The present invention will be described in detail below. The latent partially bulky filament yarn of the present invention has different shrinkage characteristics.
Although a kind of polyester is joined to a bimetal type, the polyester to be joined to the bimetal type must be a combination in which a crimp is expressed by relaxation heat treatment.

As a combination of two kinds of polyesters satisfying the above, polyethylene terephthalate is used for both kinds, and those having a difference in the intrinsic viscosity of 0.1 or more and a difference in the heat shrinkage property, isophthalic acid, 5 -Sodium sulfoisophthalic acid, dodecanedioic acid, azelaic acid, 1,
4-butanediol, 1,6-hexanediol, diethylene glycol, etc. are copolymerized with one polyethylene terephthalate or two different polyethylene terephthalates are copolymerized with these different substances to give different heat shrinkage properties. Further, it is preferable to use two kinds of polyethylene terephthalate which are copolymerized with these same substances, and the amount of copolymerization at that time is changed to give a difference in shrinkage property. However, the present invention is not limited to these. Absent.

Regarding the physical properties of the yarn, first, it is necessary to make the boiling water shrinkage of the yarn 4 to 25%. Boiling water shrinkage rate is 4
If it is less than%, the yarn will have a low shrinkage as a whole, and the yarn will not exhibit bulkiness even if heat treatment is applied. On the other hand, when it exceeds 25%, the yarn shrinks too much and becomes poor in softness, resulting in a hard-textured yarn.

Further, the standard deviation of the shrinkage ratio in the lengthwise direction of the yarn must be 1% or more. When this standard deviation is less than 1%, the variation in the shrinkage ratio of the fiber in the length direction becomes small, and the natural fiber-like feel becomes poor.

Further, it is necessary to make the expansion and contraction rate of the yarn 10% or more. If this value is less than 10%, the stretchability and the crimping performance will be poor, so that when a fabric is formed, the flexibility and bulkiness after heat treatment are poor, which is not preferable.

In order to develop the bulkiness of the latent bulkiness portion of the yarn of the present invention, the yarn is stretched to form a stretched portion and an unstretched portion, and then heat treatment is performed. When this heat treatment is applied to the yarn, a difference in the degree of orientation of the two polymers occurs in the stretched portion, so crimps develop due to the difference in shrinkage, while crimps occur in the unstretched portion even after heat treatment. do not do. This heat treatment may be performed either in the state of the yarn or the state of the cloth, but it is preferable that after the cloth such as the woven or knitted cloth is subjected to the heat treatment simultaneously in the steps of scouring and dyeing.

Next, a method for producing the polyester latent partially bulky filament yarn of the present invention will be described. First,
Using a bimetal type composite spinning device, two kinds of polyesters having different shrinkage properties are melt-spun at a spinning speed of 2500 to 4000 m / min to obtain a bimetal type polyester conjugate fiber having an ε _0.2 of 15 to 45%. ε _0.2 is spinning speed 2500-4000m /
Depending on the minutes, it can be increased to about 15-45%,
By setting ε _0.2 in this range, the boiling water shrinkage of the obtained yarn can be set to 4 to 25%.

When ε _0.2 is less than 15%, highly oriented undrawn yarn is obtained, and the fiber structure becomes too strong, so that the internal structure of the yarn may be changed even if a heat treatment is applied in a later step. No, it cannot be a soft-textured yarn. On the other hand, when ε _0.2 exceeds 45%, unoriented yarn with low orientation is obtained, and when heat treatment is applied in a subsequent step, the yarn becomes brittle or the yarn is cut by the drawing after the heat treatment.

Next, the bimetal type composite yarn obtained above is pre-heat-treated at a temperature of Tg or higher of the two polyesters constituting it and continuously subjected to a relaxation heat treatment of 1% or higher at a temperature of Tg + 100 ° C. or higher. Give. The preheat treatment temperature must be Tg or higher. If it is less than Tg, the internal structure of the highly oriented undrawn yarn cannot be changed.

The relaxation heat treatment temperature is Tg + of the fiber.
The temperature must be 100 ° C or higher. If it is less than Tg + 100 ° C, the effect of heat treatment is small, and the yarn cannot be made into a low shrinkable yarn or a heat stretched yarn. Next, the relaxation rate of relaxation heat treatment, which must be 1% or more. By setting the relaxation rate to 1% or more, the standard deviation of the boiling water shrinkage rate of the obtained yarn can be adjusted. If the relaxation rate is less than 1%, the heat shrinkage rate of the yarn before drawing cannot be reduced, and the shrinkage unevenness in the length direction of the fiber after drawing cannot be increased.

A method of performing the preliminary heat treatment and the relaxation heat treatment will be described with reference to FIGS. 1 and 2. FIG. 1 and FIG. 2 are schematic views showing an embodiment of an apparatus for performing a preliminary heat treatment and a relaxation heat treatment when producing the polyester latent partially bulky filament yarn of the present invention. When the apparatus of FIG. 1 is used, the supply yarn is unwound from the package Y, the first roller 2 below the supply roller 1 is preheated, and then the heater 3 is provided between the first roller 2 and the second roller 4. Is subjected to relaxation heat treatment, and wound around the pan 5. In addition, FIG. 2 shows that the heater 3 of FIG. 1 is a saddle-type heater 6 and the second roller 4 is a stepped roller 7. The preheated roller 2 preheats the stepped roller 7 once. After winding around the diameter,
A relaxation heat treatment is performed between the small diameter portion of the stepped roller 7 through the saddle type heater 6.

In the present invention, after the bimetal type composite filament yarn is subjected to the preliminary heat treatment and the relaxation heat treatment, the unstretched portion and the unstretched portion are formed at a stretch ratio equal to or higher than the yield point of the obtained yarn. Stretching is performed at a draw ratio at a temperature lower than the glass transition temperature (Tg). The yarn that has been subjected to the preliminary heat treatment and the relaxation heat treatment is partially stretched by this stretching to be a yarn having a stretched portion and an unstretched portion. When stretched at a temperature exceeding Tg, the fibers become uniform in the length direction, and shrinkage unevenness does not appear.

The draw ratio must be equal to or higher than the draw ratio corresponding to the yield point of the yarn obtained by the preliminary heat treatment and the relaxation heat treatment, and must be a draw ratio at which an unstretched portion and a stretched portion are formed. . By changing the draw ratio within this range, the boiling water shrinkage ratio and the standard deviation of the boiling water shrinkage ratio of the obtained yarn can be adjusted. When the draw ratio is less than the draw ratio corresponding to the yield point, shrinkage unevenness in the length direction of the fiber does not occur. Further, in the present invention, it is necessary to set the draw ratio such that the undrawn portion and the drawn portion are formed in the yarn so that the yarn is not uniformly drawn, and the upper limit of such a draw ratio is Generally, it is preferable to set the stretching ratio to natural.

The stretching method will be described with reference to FIG. FIG. 3 is a schematic view showing an embodiment of a drawing step in producing the polyester latent partially bulky filament yarn of the present invention. First, the yarn that has been subjected to the preliminary heat treatment and the relaxation heat treatment is unwound from the pan 5, and is stretched between the third roller 8 and the fourth roller 9 below the supply roller 11, and the pan 10
Roll it up.

Although the two-step method in which the preliminary heat treatment and the relaxation heat treatment are performed and then the coil is once wound and stretched is described here, the one-step method in which these processes are continuously performed without being once wound. Can also be adopted. The one-step method may be carried out by an apparatus as shown in FIG.
Pre-heat treatment is performed on the first roller 2 below the
The heater 3 is contacted between the roller 2 and the second roller 4 to perform relaxation heat treatment, and then the second roller 4 and the fourth roller 9
It is stretched between and and wound up in pan 10.

[0027]

The polyester latent partially bulky filament yarn of the present invention is composed of polyester bifilament-bonded polyester composite filaments using polyesters having different shrinkage characteristics, and has heat shrinkage and variations in characteristics. Appropriate swelling feeling and flexibility, and natural fiber-like unevenness can be imparted to the obtained cloth. In the manufacturing method for obtaining this filament yarn, first, 2
Since a bimetal type composite yarn having a specific range of ε _0.2 is used by using one kind of polyester, the yarn is highly flexible.
By subjecting this yarn to a preliminary heat treatment and a relaxation heat treatment, the yarn is made into a low-shrinkable yarn or a heat-extended yarn, and further, this is at a draw ratio equal to or higher than the yield point, and an unstretched portion and a stretched portion are formed. By stretching at a draw ratio as described above, a latent bulky filament yarn in which a stretched portion and an unstretched portion are mixed in the length direction of the yarn is obtained. After that, heat treatment gives a difference in the degree of orientation of the two polymers in the stretched portion, so crimps are expressed due to the difference in shrinkage, and the unstretched portion remains as a low shrinkable yarn or a heat stretched yarn. Exists. Then, a portion where the crimps overlap each other becomes a bulky portion, and a yarn having a bulky portion and a non-bulky portion due to minute crimps in the lengthwise direction of the yarn can be obtained.

[0028]

EXAMPLES Next, the present invention will be specifically described with reference to examples. The characteristic values in the examples were measured as follows. 1) Intrinsic viscosity [η] It was measured at 20 ° C using an equal weight mixture of phenol and ethane tetrachloride as a solvent. 2) Bulkiness The drawn yarn was cylindrically knitted and treated with boiling water, and the shape after the treatment was visually observed, and compared in 5 grades, and 3 or more were passed. 5-Very large. 4-Big. 3-Slightly large. 2-Slightly small. 1-small. 3) Flexibility After the drawn yarn is cylindrically knitted and treated with boiling water, the texture is compared in a 5-step evaluation, and 3 or more is passed. 4-Big. 3-Slightly large. 2-Slightly small. 1-small. Hereinafter, the characteristic values of 4) to 9) were measured by the method described above. 4) ε _0.2 5) Tg 6) Stretch ratio corresponding to yield point 7) Boiling water shrinkage rate 8) Standard deviation of boiling water shrinkage rate 9) Stretching elongation rate

Examples 1 to 5, Comparative Examples 1 to 3 Polyester made of polyethylene terephthalate having an intrinsic viscosity [η] of 0.72 and a glass transition temperature of 75 ° C., and an intrinsic viscosity [η] of 0.48 and a glass transition temperature of 73 ° C. Polyethylene terephthalate of was used to melt-spin a bimetal type composite filament. At this time, the spinning temperature was 295 ° C, the composite ratio was 1/1, the number of holes in the spinneret was 36, and the spinning speed and discharge rate were changed as shown in Table 1 so that the resulting undrawn yarn would be 75 denier. Spun Ε of the obtained undrawn yarn
_{0.2 is} also shown in Table 1. Next, the obtained undrawn yarn was subjected to preliminary heat treatment and relaxation heat treatment under the conditions shown in Table 2 using the apparatus shown in FIG. 1, and was once wound (relaxation heat treatment speed 400 m / min). The results of measuring the draw ratio corresponding to the yield point of this yarn are also shown in Table 2. Next, this yarn was drawn under the conditions shown in Table 3 using the device shown in FIG. 3 (drawing speed 400 m / min). The results of measuring various characteristic values of the obtained yarn are also shown in Table 3.

[0030]

[Table 1]

[0031]

[Table 2]

[0032]

[Table 3]

As is clear from Table 3, the yarns of Examples 1 to 5 have shrinkage unevenness in the length direction, and also have an excellent elastic elongation ratio.
After tubular knitting, the fabric treated with boiling water had bulkiness and flexibility. On the other hand, in Comparative Examples 1 and 2, unstretched yarns having an excessively large value of ε _0.2 were used, and thus the obtained yarns were tubularly knitted and subjected to boiling water treatment, resulting in poor flexibility. Comparative Example 3
Since an undrawn yarn having a too small value of ε _0.2 was used, the standard deviation of the boiling water shrinkage of the obtained yarn was too small and the bulkiness after boiling water treatment was poor.

Examples 6 to 8 and Comparative Examples 4 to 8 Undrawn yarn Nos. Shown in Table 1 Using the device shown in Fig. 2 and the yarn shown in Fig. 5, pre-heat treatment and relaxation heat treatment (relaxation heat treatment speed 400 m / min) were performed, and the yield of the yarn obtained here was applied. The results of measuring the draw ratio corresponding to the points are also shown in Table 4. Next, this yarn was drawn under the conditions shown in Table 5 using the apparatus shown in FIG. 3 (drawing speed 400 m / min). The characteristic values of the yarn obtained here are also shown in Table 5.

[0035]

[Table 4]

[0036]

[Table 5]

As is clear from Table 5, the yarns of Examples 6 to 8 have shrinkage unevenness in the length direction, have an excellent expansion and contraction elongation ratio, and the fabrics subjected to boiling water treatment after knitting are bulky. And had flexibility. On the other hand, in Comparative Example 4, the relaxation rate of the relaxation heat treatment was 0%, so the standard deviation of the boiling water shrinkage rate of the obtained yarn was too small, and the bulkiness after boiling water treatment was poor. In Comparative Example 5, since the relaxation heat treatment temperature was low, the obtained yarn had a too large boiling water shrinkage ratio and was inferior in flexibility after the boiling water treatment. In Comparative Example 6, since the drawing temperature was too high, the standard deviation of the boiling water shrinkage ratio and the stretching elongation ratio of the obtained yarn were small, and the bulkiness after the boiling water treatment was poor.
In Comparative Example 7, since the preheat treatment temperature was too low, the standard deviation of the boiling water shrinkage of the obtained yarn was small, and the flexibility after the boiling water treatment was poor. Since Comparative Example 8 had a draw ratio lower than the draw ratio corresponding to the yield point, the obtained yarn had a small standard deviation of the boiling water shrinkage ratio of the yarn and a small stretch elongation ratio, and thus had a high bulkiness after the boiling water treatment. It was inferior.

Examples 9 to 11 Polyester A made of polyethylene terephthalate having an intrinsic viscosity [η] of 0.72 and a glass transition temperature of 75 ° C., and 5-sodium sulfoisophthalic acid having an intrinsic viscosity [η] of 0.65 and a glass transition temperature of 70 ° C. Polyester B made of polyethylene terephthalate copolymerized with 1.5 mol% of ethylene, an intrinsic viscosity [η] of 0.70, and a glass transition temperature of 69 ° C with isophthalic acid.
Using the polyester C made of polyethylene terephthalate copolymerized with 10 mol%, the bimetal type composite fibers were melt-spun in the combinations shown in Table 6. The spinning temperature at this time is 295
℃, composite ratio 1/1, spinneret hole number 36, spinning speed 3200
It was spun to have a fineness of 75 denier at m / min. The ε _{0.2 of the} undrawn yarn obtained here is also shown in Table 6. Next, the undrawn yarn thus obtained was subjected to preliminary heat treatment, relaxation heat treatment and drawing under the conditions shown in Table 6 by using the apparatus shown in FIG. 4 (drawing speed 400 m / min). The characteristic values of the yarn obtained here are also shown in Table 6. In addition, the draw ratio corresponding to the yield point of the yarn after the relaxation heat treatment was examined by winding the yarn discharged from the second roller 4 as a test directly on the pan 10.

[0039]

[Table 6]

As is clear from Table 6, the yarns of Examples 9 to 11 have shrinkage unevenness in the lengthwise direction and have an excellent expansion / contraction rate, and the fabrics subjected to boiling water treatment after tubular knitting are bulky. And had flexibility.

[0041]

INDUSTRIAL APPLICABILITY The polyester latent partially bulky filament yarn of the present invention, when subjected to a heat treatment, exhibits shrinkage unevenness and bulkiness unevenness in the length direction of the fiber, and is also a natural fiber-like special It may have a texture. Further, according to the production method of the present invention, it becomes possible to stably produce the polyester latent partially bulky filament yarn having the above-mentioned advantages by heat treatment with a simple facility.

[Brief description of drawings]

FIG. 1 is a schematic view showing one embodiment of an apparatus for performing a preheat treatment and a relaxation heat treatment, which is used when a polyester latent partially bulky filament yarn of the present invention is produced by a two-step method.

FIG. 2 is a schematic view showing another embodiment of the apparatus similar to FIG.

FIG. 3 is a schematic view showing one embodiment of a stretching step used in producing the polyester latent partially bulky filament yarn of the present invention by a two-step method.

FIG. 4 is a schematic view showing one embodiment of an apparatus for producing the polyester latent partially bulky filament yarn of the present invention by a one-step method.

FIG. 5 is a graph showing a strength-elongation curve for obtaining a yield point of an undrawn yarn.

[Explanation of symbols]

 1, 11 Supply roller 2 First roller 3 Heater 4 Second roller 5, 10 Pane 6 Saddle type heater 7 Stepped roller 8 Third roller 9 Fourth roller Y package

Claims (2)

[Claims] 1. A polyester latent partially bulky filament yarn comprising a polyester composite filament in which two kinds of polyesters having different shrinkage properties are joined in a bimetal type, and the physical properties of the yarn satisfy the following formula. 4 ≦ S100 ≦ 25 σS ≧ 1 E ≧ 10 S100: Boiling water shrinkage rate of yarn (%) σS: Standard deviation of boiling water shrinkage rate of yarn (%) E: Stretching expansion rate (%) of yarn (σS is , The boiling water shrinkage ratio is obtained by measuring 50 times continuously every 10 cm in the length direction of the yarn.) 2. A bimetal type composite spinning apparatus is used to spin two kinds of polyesters having different shrinkage characteristics at a spinning speed of 2500 to 4000.
Melt-spun at m / min and the structural integrity parameter (ε
_0.2 ) is a bimetal type polyester composite filament yarn having a content of 15 to 45%, and then preheated at a temperature not lower than the average glass transition temperature (Tg) of two types of polyester, and the glass transition temperature (Tg) + 100 ° C. continuously. 1% at above temperature
After subjected to the above relaxation heat treatment, a temperature lower than the glass transition temperature (Tg) at a draw ratio equal to or higher than the yield point of the obtained yarn and a draw ratio at which an unstretched portion and a stretched portion are formed. A method for producing a bulky filament yarn of polyester latent portion, characterized by being stretched.