WO2015151220A1

WO2015151220A1 - Polyamide latent crimped yarn and method for manufacturing same

Info

Publication number: WO2015151220A1
Application number: PCT/JP2014/059598
Authority: WO
Inventors: 山下　裕之
Original assignee: Ｋｂセーレン株式会社
Priority date: 2014-03-31
Filing date: 2014-03-31
Publication date: 2015-10-08
Also published as: CN106103822A; JPWO2015151220A1

Abstract

　To obtain a polyamide latent crimped yarn having sufficient stretchability without being subjected to covering without using a special copolymer. A bonded latent crimped yarn comprising a resin composition (component (1)), which comprises poly-meta-xylene adipamide and a polyamide (6), and a polyamide resin (component (2)), wherein the latent crimped yarn satisfies criteria (1)-(3): (1) Elongation rate: 45% or above. (2) Resin viscosity difference between component (1) and component (2) ((component (1))‒(component (2)): ‒0.50 to 1.00. (3) Mass ratio of poly-meta-xylene adipamide:polyamide (6) in component (1): 25:75 to 70:30.

Description

Polyamide latent crimped yarn and method for producing the same

The present invention relates to a polyamide crimped yarn having high crimpability in which two kinds of polyamides are arranged in a bonded mold.

As crimped yarns used for clothing and the like, natural fibers such as cotton and wool whose shape and crimp are reversibly changed by changes in humidity are well known.
Various attempts have also been made to obtain crimps for synthetic fibers.
For example, a yarn made of a single polymer such as a polyester such as polyethylene terephthalate, which is often used for clothing, or a polyamide 6, polyamide 12 or the like, has almost no stretchability. The torque is applied to the torsion to give the crimp. When crimping is applied by processing such as false twisting, surface wrinkles are likely to occur when a woven or knitted fabric is formed. In order to prevent the occurrence of wrinkles, if hot water treatment is applied to the fabric, the torque of the crimped yarn due to processing such as false twisting will be reduced, and the stretchability and stretch recovery will not be sufficient. Not suitable to get.
In addition, there is a method in which an elastic polymer such as polyurethane is used as a crimped yarn to obtain a stretchable and highly shrinkable fabric, but in the case of polyurethane alone, the dyeability and light resistance are poor. As a result, problems such as sticking between yarns and yarns occur, so that polyamide is usually used after covering.
Further, Patent Document 1 discloses a fiber in which polyamide or polyester is combined into a side-by-side type or a core-sheath type using a polyamide 12 elastomer as an elastic polymer.
On the other hand, various methods for imparting stretchability to a fiber using a composite fiber of two different types of general-purpose polymers as a crimped yarn have been studied. For example, a method in which different resins such as polyester and polyamide are combined to form a crimped yarn as a composite fiber, or a method in which a crimped yarn is used as a composite fiber in which the same resins having different viscosity are combined.
Patent Document 2 describes a polyamide latent crimped yarn having a high crimp property in which a specific amount of polymetaxylene adipamide is blended with a high viscosity polymer and the viscosity of the high viscosity polymer and the low viscosity polymer is controlled. Yes.

JP-A-57-193521 Japanese Patent No. 4097788

However, the polyurethane elastic yarn requires a covering processing cost, which is expensive and disadvantageous in cost. Moreover, the thing using the copolymer polyamide using the polyamide 12 elastomer like patent document 1 also becomes disadvantageous in cost.
In addition, a composite fiber made by combining different polymers such as general-purpose polyester and polyamide produces crimp in the usual post-process, so the cost for obtaining the crimp is low, but spinning and drawing In other words, the resin is easily peeled off during post-processing.
In addition, when resins of the same kind with different viscosity differences are combined, sufficient crimps cannot be obtained, the elasticity of the fibers themselves is not sufficient, and it is difficult to obtain a highly elastic fabric.
Furthermore, the latent crimped yarn described in Patent Document 2 has a satisfactory crimp rate to some extent, but does not yet provide sufficient stretchability.
Accordingly, an object of the present invention is to solve the above-described problems and to obtain a polyamide latent crimped yarn having sufficiently excellent stretchability without using a covering process or a special copolymer.

That is, the present invention is a bonded-type latent crimped yarn composed of a resin composition (component 1) composed of polymetaxylene adipamide and polyamide 6 and a polyamide resin (component 2). A polyamide latent crimped yarn satisfying the requirements of 1) to (3) is a first gist.
(1) Elongation rate is 45% or more (2) Difference in resin viscosity between component 1 and component 2 [(component 1) − (component 2)] = − 0.50 to 1.00
(3) Polymetaxylene adipamide of component 1: polyamide 6 mass ratio = 25: 75 to 70:30
As a suitable method for producing the crimped yarn, two kinds of polyamide components, that is, a resin composition (component 1) composed of polymetaxylene adipamide and polyamide 6 and a polyamide resin (component 2) are bonded together. A latent crimped yarn obtained by melt composite spinning, wherein the spinning speed is 1200 to 4500 m / min, and the heat setting temperature in the drawing step is 150 ° C. or less. Can be mentioned.
A more preferable production method comprises a resin composition (component 1) composed of polymetaxylene adipamide and polyamide 6 (component 1) and polyamide (component 2), and the difference in viscosity between component 1 and component 2 ((component 1) When producing a latent crimped yarn obtained by laminating two kinds of polyamide components having-(component 2)] of -0.50 to 0.00 and melt-spinning, the heat set temperature in the drawing step is A method for producing a polyamide latent crimped yarn having a temperature of 125 ° C. or lower can be mentioned.

According to the present invention, a polyamide latent crimped yarn having high crimpability and excellent stretchability and high shrinkage can be obtained without performing covering processing or false twisting.
In addition, high stretchability can be obtained without using a copolymer such as a special polyamide elastomer, which is advantageous in terms of cost.

FIG. 1 shows an example of a fiber cross section of the latent crimped yarn of the present invention.

Hereinafter, the present invention will be described in detail.
The present invention relates to a bonded type latent crimped yarn composed of two polyamide components composed of a resin composition (component 1) comprising polymetaxylene adipamide and polyamide 6 and a polyamide resin (component 2). It is.

In the present invention, the mass ratio of the resin composition of Component 1 is 25:75 to 70:30, particularly preferably 30:70 to 55:45 for polymetaxylene adipamide and polyamide 6, respectively. Within this range, the hot water shrinkage is sufficient, and the fiber has high shrinkage and crimpability. When the polymetaxylene adipamide has a mass ratio of less than 25% by mass and more than 70% by mass, it does not shrink well with hot water, and fibers with high crimpability cannot be obtained. If the ratio of polymetaxylene adipamide is 45 to 55% by mass, the hot water shrinkage rate is particularly large, so that a woven fabric or knitted fabric with high density, high shrinkage, and high stretchability can be obtained. it can.

The polyamide 6 used in Component 1 preferably has a relative viscosity of more than 2.2 from the viewpoint of melt spinning stability. More preferably, the viscosity is 2.4 or more, and particularly preferably the relative viscosity exceeds 2.7. Further, although there is no restriction on the upper limit of the relative viscosity, a relative viscosity of up to 3.5 is sufficient from the viewpoint of spinning operation stability.

The polymetaxylene adipamide used in Component 1 preferably has a relative viscosity exceeding 2.1 from the viewpoint of melt spinning stability. More preferably, it is 2.3 or more, and particularly preferably the relative viscosity is more than 2.5. Moreover, although there is no restriction | limiting in the upper limit of relative viscosity, relative viscosity 3.3 is enough from a viewpoint of spinning operation stability.

The moisture content of the polyamide and polymetaxylene adipamide used in Component 1 of the present invention is preferably 300 ppm or less from the viewpoint of spinning operability. It is preferable to strengthen the drying as the single yarn fiber is thinner. In this case, it is more preferable not to exceed 100 ppm.
More preferably, it is 50 to 100 ppm.

In the present invention, the relative viscosity of the resin composition of Component 1 is preferably 2.2 to 3.4 from the viewpoints of spinning operation and crimping performance, and is 2.6 to 3.2. It is more preferable.

The polyamide resin used for component 2 of the present invention may be polyamide 6, polyamide 12, polyamide 66, or the like, and is not particularly limited, but homopolyamide is preferred. From the viewpoint of cost and versatility, polyamide 6 and polyamide 66 are preferable. In addition, you may add a matting agent etc. to a polymer as a 3rd component.

When the polyamide resin used in component 2 is polyamide 6, the relative viscosity of polyamide 6 is preferably more than 2.2 from the viewpoint of melt spinning stability. More preferably, it is 2.4 or more, and particularly preferably, the relative viscosity exceeds 2.7. Further, although there is no restriction on the upper limit of the relative viscosity, a relative viscosity of up to 3.5 is sufficient from the viewpoint of spinning operation stability.

The relative viscosity of the component 2 resin is preferably 2.1 to 3.5 and more preferably 2.3 to 3.0 from the viewpoint of maintaining a high elongation rate and heat shrinkage stress. preferable.

The moisture content of the polyamide resin of component 2 is preferably 300 ppm or less from the viewpoint of spinning operability. The finer the single yarn fineness, the better the drying, and in this case, it is better not to exceed 100 ppm.

DETAILED DESCRIPTION OF THE INVENTION The present invention is a bonded type latent crimped yarn composed of two polyamide components composed of component 1 and component 2.

As a method for laminating latent crimped yarns of the present invention, for example, a method in which component 1 and component 2 are separately melted, bonded and spun at the base portion, and bonded as a composite fiber is preferably exemplified.

The fiber cross-sectional shape (cross-sectional shape perpendicular to the fiber longitudinal direction) of the latent crimped yarn of the present invention is not limited to a round cross-section, and may be an irregular cross-section such as a triangle, square, or peanut type.

Examples of the arrangement of laminating component 1 and component 2 include a method of arranging component 1 and component 2 in a side-by-side type, a method of arranging each in a side-by-side repetitive type, a method of arranging in an eccentric core-sheath type, and the like. In view of spinning operability and high crimping performance, a side-by-side arrangement method is preferred.

An example of a suitable cross-sectional shape of the latent crimped yarn of the present invention is shown in FIG.
1 (a) is a side-by-side type composite fiber having a round cross section, FIG. 1 (b) is a side-by-side type composite fiber having a triangular cross section, FIG. 1 (c) is a side-by-side type composite fiber having a square cross section, and FIG. It is an example of the side by side type | mold composite fiber of the peanut type cross section which has a dent in the composite part of the component 1 and the component 2. FIG.
In the latent crimped yarn of the present invention, those having a round cross section and a peanut type cross section are preferable from the viewpoint that sufficient stretchability can be easily obtained, and a peanut type cross section is particularly preferable.
The ratio of the long side A to the short side B (long side / short side) is 1.1 to 3.0, more preferably 1.1 to 3.0, in order to give the fiber itself excellent stretchability. 2.2.

The relative viscosity difference between the polymers of component 1 and component 2 is preferably in the range of (component 1) − (component 2) = − 0.50 to 1.00. Within this range, a polyamide latent crimped yarn excellent in crimpability can be obtained while maintaining spinning operability.
That is, when it is less than −0.50, the hot water shrinkage ratio of the whole fiber is low, and a sufficient expansion ratio cannot be obtained. On the other hand, if the viscosity difference exceeds 1.00, the spinning operability may be impaired. More preferably, (component 1) − (component 2) = − 0.25 to 0.50.

The elongation rate of the polyamide latent crimped yarn of the present invention is 45% or more. If the elongation rate is 45% or more, the stretchability is excellent and sufficient crimps can be generated. As a result, it is possible to obtain a fabric having stretchability while being a high-density fabric. And in post-processing such as dyeing, the latent crimped yarn shrinks, and a high-shrinkage high-density fabric can be obtained.
In addition, More preferably, it is 50% or more, More preferably, it is 60% or more.

The breaking strength of the polyamide latent crimped yarn of the present invention is preferably 3.2 cN / dtex or more from the viewpoint of maintaining good weaving operability without yarn breakage. More preferably, it is 3.5 cN / dtex or more.

Further, the hot water shrinkage rate of the polyamide latent crimped yarn of the present invention is preferably 45% or more from the viewpoint of high crimp performance. More preferably, it is 55% or more. The upper limit is preferably 85% or less from the viewpoint of easily preventing the texture of the dough after heat treatment.

The MAX value (thermal shrinkage stress) of the shrinkage stress of the polyamide latently crimped yarn of the present invention is 0.2 to 1.0 cN / dtex from the viewpoint of easily obtaining a high-density fabric by shrinking and maintaining a good texture. It is preferable that More preferably, it is 0.25 to 0.5 cN / dtex.
That is, if the thermal shrinkage stress is too small, there is a risk that the fabric shrinks at the time of shrinkage and a high-density fabric cannot be obtained. There is a risk that.

The polyamide latent crimped yarn of the present invention preferably has a number of crimps described later of 90 to 500. When it is within this range, when it is made into a fabric, a good crimp is easily expressed, and it becomes easy to obtain a high-density fabric with a good texture.

Next, a method for obtaining the polyamide latent crimped yarn of the present invention will be described.
The polyamide latently crimped yarn of the present invention can be obtained by a two-step method (conventional method) of spinning and drawing, a direct spinning method, or the like. As the stretching method, one-stage stretching, multi-stage stretching, or the like can be selected as appropriate.

Hereinafter, more specific methods will be exemplified.
First, polymetaxylene adipamide of component 1 and polyamide 6 are prepared. Both are mixed by kneading | mixing etc. and a resin composition (component 1) is obtained. Next, the resin of component 2 is prepared.
Components 1 and 2 are melt-kneaded, guided to a die pack, discharged from a nozzle so as to have a predetermined cross section, and melt-spun. Here, the spinning temperature is preferably about 260 to 290 ° C.
Then, after cooling and winding up, it is stretched to obtain a stretched yarn. In the case of the conventional method or the direct spinning method, the speed of the godet roll (spinning speed) at which the yarn discharged from the nozzle is first wound is preferably 1200 to 4500 m / min. By setting such a speed, the stretch rate of the polyamide crimped yarn can be 45% or more, and when it is made into a fabric, a stretchable product can be obtained and the density can be increased.
When the spinning speed is increased, the spinning draft is increased, whereby the orientation of molecular chains in the fiber advances, and the fiber is wound in a state in which the strain in the fiber is increased. By further stretching the fiber with this strain, by adding molecular chain orientation and accumulating strain in the fiber, it is possible to give a high degree of elongation, a high degree of crimping, and high contractibility with high stretchability. It is presumed that a polyamide latent crimped yarn can be obtained. In this respect, the spinning speed is preferably 1200 m / min or more, more preferably 1800 m / min or more, and further preferably 2200 m / min or more and 2700 m / min or more. In consideration of the yarn operability, the upper limit is preferably about 4500 m / min, more preferably 4000 m / min.

The heat setting temperature in the stretching process of the conventional method or the direct stretching method is preferably 150 ° C. or less (when the relative viscosity difference is −0.50 to ± 0.00, the heat setting temperature is 125 ° C. or less). More preferably, the heat setting temperature is 145 ° C. or lower, and more preferably, the heat setting temperature is 125 ° C. or lower. When the heat setting temperature exceeds 150 ° C., the difference in hot water shrinkage between each component 1 and component 2 single yarn is reduced, and the hot water shrinkage of the entire composite fiber is also lowered. Thereby, since an elongation rate becomes low and it becomes difficult to express a crimp, the high density property and the high elasticity as a fabric are impaired.

As described above, in the present invention, the component 1 composed of the polyamide resin composition and the component 2 composed of the polyamide resin are set within a specific relative viscosity difference range to increase the spinning speed during spinning, Elasticity that can produce extremely high crimps with a high elongation rate by using latently crimped yarns such as composite fibers with both components bonded together, such as by controlling the heat setting temperature at a low level during the yarn making process. Excellent high shrinkage polyamide latent crimped yarn can be obtained.

That is, first, component 1 is composed of polymetaxylene adipamide and polyamide 6, each having a mass ratio of 25:75 to 70:30, and component 2 as a polyamide resin. to paste together. Here, when each component of component 1 is made into a fiber as a single polymer, there is no significant difference in hot water shrinkage between component 1 and component 2, and no crimp is developed. By constituting, the hot water shrinkage rate of the component 1 single yarn can be increased. For this reason, it is easy to increase the difference between the component 2 and the hot water shrinkage, and it is easy to obtain a product having a high crimp.
Then, as seen in the preferred production method of the present invention, the fiber is directly oriented under the nozzle by increasing the spinning speed, etc., and wound in a state in which the strain in the fiber is increased. High crimps can be imparted by further stretching the fiber having a length and storing the strain in the fiber. Furthermore, by suppressing the heat setting temperature to the fiber at the time of drawing, the oriented molecular chain is not fixed (molecular chain distortion is not relaxed), so that the difference in thermal shrinkage between Component 1 and Component 2 is maintained large. Therefore, high crimpability can be maintained. By these ideas, the present invention can obtain a high-shrinkage polyamide latent crimped yarn having a high elongation rate and excellent stretchability.

The polyamide latent crimped yarn obtained in this way has a good weaving property because it can maintain an appropriate strength. In addition, from the high shrinkage stress and high crimpability of the latent crimped yarn of the present invention, when subjected to shrinkage processing by weaving, it is possible to obtain a fiber having a higher density and good texture. In addition, since it has high crimpability, it is possible to obtain a fabric with high density and high stretchability, and it can be expected to have a good texture not found in polyester high-density fabrics.

Hereinafter, the present invention will be described in detail with reference to examples. In addition, this invention is not limited to the Example described below.

Each physical property was measured as follows.
A. Measurement of relative viscosity The relative viscosity is measured using an automatic viscosity measuring apparatus (SS-600-L1 type) manufactured by Shibayama Kagaku Seisakusho. The polymer is dissolved at a concentration of 1 g / dl using 95.8% concentrated sulfuric acid as a solvent, and measurement is performed at 25 ° C. in a thermostatic bath.

B. Measurement of Breaking Strength and Breaking Elongation Measured according to JIS-L-1013 using an AGS-1KNG autograph tensile tester manufactured by Shimadzu Corporation under the conditions of a sample yarn length of 20 cm and a constant speed tensile speed of 20 cm / min. The value obtained by dividing the maximum value of the load in the load-elongation curve by the fineness is defined as the breaking strength (cN / dtex), and the elongation at that time is defined as the breaking elongation (%).

C. Measurement of heat shrinkage stress The heat shrinkage stress is measured using a KE-II type shrinkage stress measuring device manufactured by Kanebo Engineering. Measures the thermal contraction force when heated from room temperature at a heating rate of 120 ° C / min by applying an initial load of fineness x 2/30 (cN) to a sample with a thread end tied as a 5 cm long loop. To do. The highest point of the measured thermal contraction force is defined as the peak (cN) of thermal contraction force, and the temperature at that time is defined as the thermal contraction force peak temperature (° C.). A value obtained by dividing the maximum value of the heat shrinkage force by twice the fiber fineness is defined as heat shrinkage stress (cN / dtex).

D. Calculation of Elongation Rate / Hot Water Shrinkage A casket having a length of 50 cm is prepared at a return round trip of 0.1 g / d, and the length at that time is L0 = 50. Then, apply a load of 1.2 mg / d and let stand for 30 minutes. After being immersed in boiling water for 15 minutes in this state, it is air-dried for 24 hours and measured (L1). Next, the length was measured after 30 seconds by applying a 5 mg / d load (L2), the length was measured after 30 seconds by applying a 300 mg / d load (L3), and the following formula was calculated.
Elongation rate (%) = (L3-L2) / L2 × 100
Hot water shrinkage (%) = (L0−L1) / L0 × 100
In addition, the hot water shrinkage rate of the component 1 and the component 2 in the table | surface of the following examples and comparative examples shows the thing at the time of obtaining a single fiber by the manufacturing method of each component and the same conditions as each example.
E. Number of crimps The sample yarn was put into a boiling water bath, immersed in the bath for 30 minutes, air-dried for 30 minutes as it was, and then the number of crimps per 1 cm was measured with an optical microscope.

[Example 1]
Relative viscosity of component 1 polyamide (polymetaxylene adipamide + polyamide 6) 2.7 (moisture content 35 ppm) and 3.0 (moisture content 55 ppm), respectively, and component 2 (polyamide 6) relative viscosity 2 .4 (water content 50 ppm) chips were vacuum dried. Furthermore, each polymer was uniformly mixed with a blender so that the mass ratio was 30:70. This was melt-spun using a spinning nozzle with a conventional method at a spinning temperature of 282 ° C., a take-up speed (spinning speed) of 2770 m / min, so that component 1: component 2 had a mass ratio of 1: 1, and the fiber cross section was An undrawn yarn, which is a side-by-side peanut-type composite fiber, was obtained.
The undrawn yarn is aged for one day, drawn at a drawing speed of 800 m / min, a spindle rotation speed of 7500 rpm, a roll heater at 70 ° C., a plate heater at 100 ° C., and a draw ratio of 1.8 times to obtain a latent crimped yarn of 44 dtex / 12f. (Long side / short side of fiber cross section: 1.8).
Table 1 shows the results of measuring the mass ratio of Component 1 and Component 2 and the physical properties of the resulting polyamide latent crimped yarn.

[Examples 2, 3, 4, Comparative Examples 1 and 2]
The latent potential is the same as in Example 1 except that the mass ratio of component 1 polymetaxylene adipamide and polyamide 6 is changed to 40:60, 50:50, 65:35, 20:80 and 75:25, respectively. A crimped yarn was obtained. The results are shown in Table 1.

In Comparative Example 1, the mixing ratio of the polymetaxylene adipamide of component 1 is low, and the hot water shrinkage of the component 1 single fiber is low. Comparative Example 2 also has a high mixing ratio of component 1 polymetaxylene adipamide and a low hot water shrinkage. For this reason, since the difference in hot water shrinkage between the components 1 and 2 in Comparative Examples 1 and 2 was small, a sufficient elongation rate could not be obtained. On the other hand, when the mixing ratio of the polymetaxylene adipamide of component 1 and the polyamide 6 is 30:60 to 65:35, the hot water shrinkage as a single fiber is high, and the ratio of 50:50 is The hot water shrinkage rate became the maximum. Thus, by making the hot water shrinkage rate as a single fiber of component 1 high, the difference in hot water shrinkage rate between component 1 and component 2 can be increased, and obtained from Examples 1 to 3. The latent crimped yarn had a high elongation rate and high stretchability.
Next, weaving using Examples 1 to 4 and Comparative Examples 1 and 2 followed by refining, followed by dyeing to obtain a fabric. For Examples 1 to 4, good crimps were obtained. Was developed, resulting in a high-density fabric with excellent stretchability. In particular, Example 3 was excellent. On the other hand, the fibers obtained in Comparative Examples 1 and 2 did not become a sufficiently high-density fabric and also had a low stretchability because the crimp rate was low. In addition, about the thing of the comparative examples 1 and 2, the crimp was not fully expressed.
In Examples 1 to 4, the heat shrinkage stress is further high, and by having sufficient stress, it is possible to obtain a fabric having a good elasticity and a suitable elasticity and a high density fabric. It was.

Also, two latent crimped yarns obtained from Example 3 and Comparative Example 1 were double-twisted to produce a tubular knitted fabric, and then unwound to obtain a 1000 mm × 160 mm fabric. These fabrics were immersed in hot water treatment at 100 ° C. for 30 minutes, and the surface shrinkage after 24 hours was measured. At this time, the fabric obtained from the yarn of Example 3 contracted to 620 mm × 130 mm, and the surface contraction rate was 50.4%. The elongation recovery was 95%, and the elongation rate was 65%. On the other hand, the fabric obtained from the yarn of Comparative Example 1 was 900 mm × 154 mm, and the surface shrinkage rate was 86.7%, which hardly contracted. The elongation recovery was 85% and the elongation rate was 25%. Therefore, compared with the one obtained from Comparative Example 1, the latent crimped yarn obtained from Example 3 is a high-density fabric and has good elasticity and stiffness because it sufficiently contracts and stretches. A stretchable fabric can be obtained.

[Examples 3, 5 to 12, Comparative Examples 3 to 5]
Each physical property of the drawn yarn obtained by melt spinning and drawing according to the method described in Example 2 was measured except that the relative viscosity of the polyamide 6 of component 1 and component 2 was changed. Further, three conditions are set for the relative viscosity of component 1, and the relative viscosities of component 1 and component 2, respectively, are such that component 1> component 2, component 1 and component 2 are close in value ((component 1)-(component 2)) = -0.02 to 0.02), component 1 <component 2
The results are shown in Table 2.

The latent crimped yarns obtained from Examples 3 and 5 to 12 had a hot water shrinkage rate of 45% or more and a stretch rate of 45% or more, and were crimped yarns having good crimp expression and high elongation rate. .
As in Comparative Examples 3, 4, and 5, the latent crimped yarn obtained under the condition that Component 2 has a higher relative viscosity ((Component 1)-(Component 2)) is less than -0.5 is There was a tendency for the difference in hot water shrinkage between component 2 and component 2 to be small, and the elongation was low.
In Examples 7, 9, and 12, as in Comparative Examples 3, 4, and 5, when the relative viscosity is Component 1 <Component 2, and the difference in relative viscosity is relatively small ((Component 1) − (Component 2) ) = − 0.5 or more and less than 0.0). In this case, a latent crimped yarn having a sufficiently high elongation rate was obtained due to the high hydrothermal shrinkage rate of Component 1.
In the case of component 1> component 2 as in Examples 3, 5, 6, 8, 10, 11, and 11, the conditions for component 1 and component 2 are almost the same ((component 1) − (component 2) = − 0.2). In the case of ~ 0.2), a latent crimped yarn having a hot water shrinkage rate of 50% or more and an elongation rate of 55% or more was obtained, and a latent crimp yarn having a high crimp rate and extremely excellent stretchability was obtained. .
Further, the higher the relative viscosity of Component 1 and Component 2, the greater the elongation rate and the heat shrinkage stress. Thereby, the higher the relative viscosity of Component 1 and Component 2, the greater the elongation rate and the heat shrinkage stress. As a result, weaving, refining, and dyeing yielded a fabric, and it was possible to obtain a bulky, high-density stretch-rich material.
Further, weaving using the latent crimped yarns obtained in Examples 3, 5 to 12 and Comparative Examples 3 to 5, and then refining and dyeing to obtain a fabric, the comparative product is a sufficiently high density fabric. However, the example product exhibited a good crimp and was able to obtain a bulky, high-density stretchy fabric. In particular, Examples 3, 5, 6, 8, 10, and 11 were bulky and excellent in elasticity.

[Examples 3, 13 to 16]
Each physical property was measured and evaluated for the latent crimped yarn obtained by melt spinning and drawing according to the method described in Example 3 except that the heat treatment temperature (plate heater temperature) at the time of drawing was changed. The results are shown in Table 3.

[Comparative Examples 4, 6, and 7]
Each physical property was measured and evaluated for the latent crimped yarn obtained by melt spinning and drawing according to the method described in Comparative Example 4 except that the heat treatment temperature (plate heater temperature) at the time of drawing was changed. The results are shown in Table 3.

[Examples 5, 17, 18]
Each physical property was measured and evaluated for the latent crimped yarn obtained by melt spinning and drawing according to the method described in Example 5 except that the heat treatment temperature (plate heater temperature) at the time of drawing was changed. The results are shown in Table 3.

[Examples 8 and 19, Comparative Example 8]
Each physical property was measured and evaluated for the latent crimped yarn obtained by melt spinning and drawing according to the method described in Example 8 except that the heat treatment temperature (plate heater temperature) at the time of drawing was changed. The results are shown in Table 3.

Under the conditions in which the relative viscosity of component 1 is higher than the relative viscosity of component 2 as in Examples 3, 13 to 16 and Examples 5, 17, and 18, the higher the heat treatment temperature (plate heater temperature), the hot water shrinkage of the entire fiber. There was a tendency for the rate to decline. However, even with a high temperature heat set at a heat treatment temperature of 150 ° C., the elongation rate was 45% or more, a sufficient crimp performance, and a stretched latent crimped yarn. Also, the higher the heat setting temperature, the greater the heat shrinkage stress and fiber strength. This makes it possible to obtain a stretched latent crimped yarn having excellent physical properties such as fiber strength, since a material having excellent stretchability can be obtained while increasing the heat setting temperature.
Further, under the conditions in which the relative viscosity of Component 1 is lower than the relative viscosity of Component 2 (relative viscosity difference is less than −0.5) as in Comparative Examples 4, 6, and 7, Examples 3, 13, 14, 15, 16 In the same way as the heat treatment temperature (plate heater temperature) is higher, the hot water shrinkage rate of the entire fiber is reduced, and the elongation rate is less than 45% under all heat setting temperature conditions, resulting in a latent crimped yarn having low crimpability. .
Even in the conditions where the relative viscosity of component 1 is lower than the relative viscosity of component 2 (relative viscosity difference is about −0.1) as in Comparative Example 8 and Examples 8 and 19, the hot water shrinkage ratio is higher as the heat set temperature is higher. Fell. However, in Comparative Example 8, the hot water shrinkage rate of the entire fiber was as high as 50.9%, but the elongation rate was less than 45%. However, when the heat set temperature was 125 ° C. or lower as in Examples 8 and 19, both the hot water shrinkage and the elongation of the latent crimped yarn were high.
After weaving the example product and the comparative product, the fabric was obtained by refining and dyeing to obtain a fabric. The comparative product was not bulky and stretchable, but had a high elongation rate. Examples 3, 5, 8, and 13 to 19 were bulky, high density, and stretchable fabrics. In particular, the example product having a high elongation rate was a fabric excellent in bulkiness, high density, and stretchability.

[Examples 10, 20 to 24, Comparative Example 9]
Each physical property was measured and evaluated for the latent crimped yarn obtained by melt spinning and stretching according to the method described in Example 10 except that the spinning speed during spinning and the draw ratio during stretching were changed. The results are shown in Table 4.

At the cutting speed of Comparative Example 9 at 800 m / min, the difference in hot water shrinkage between the component 1 and component 2 single fibers was extremely low. Along with this, the hot water shrinkage ratio of the entire composite fiber decreased, and the elongation ratio decreased. The latent crimped yarns obtained from Examples 10 and 20 to 24 having a take-up speed of 1200 m / min or more had a sufficient hot water shrinkage rate, elongation rate, and heat shrinkage stress. Further, the higher the spinning speed (in this condition, the take-up speed = the take-up speed), the strength decreased slightly, but the hot water shrinkage rate and elongation rate could be increased.
In addition, when weaving, refining and dyeing using the polyamide latent crimped yarns obtained in Examples 10, 20 to 24 and Comparative Example 9, the fabric obtained from Comparative Example 9 has a low density and is bulky. Although a stretchable fabric could not be obtained, the example product had a high density, a good crimp, and a bulky and stretchable fabric. In addition, a thing with a favorable elongation rate was obtained.

A Short side B Long side

Claims

A bonded-type latent crimped yarn comprising a resin composition (component 1) comprising polymetaxylene adipamide and polyamide 6 and a polyamide resin (component 2), comprising the following (1) to (3) Polyamide latent crimped yarn that satisfies the requirements of
(1) Elongation rate is 45% or more (2) Difference in resin viscosity between component 1 and component 2 [(component 1) − (component 2)] = − 0.50 to 1.00
(3) Polymetaxylene adipamide of component 1: polyamide 6 mass ratio = 25: 75 to 70:30
Laminated crimped yarn obtained by melt compound spinning is manufactured by bonding two polyamide components, a resin composition (component 1) composed of polymetaxylene adipamide and polyamide 6 and a polyamide resin (component 2). The method for producing a polyamide latent crimped yarn according to claim 1, wherein the spinning speed is 1200 to 4500 m / min, and the heat setting temperature in the drawing step is 150 ° C or lower.
It consists of a resin composition (component 1) composed of polymetaxylene adipamide and polyamide 6 and polyamide (component 2), and the viscosity difference [(component 1) − (component 2)] between component 1 and component 2 is −0. 3. The heat set temperature in the yarn forming process is 125 ° C. or lower when producing a latent crimped yarn obtained by laminating two kinds of polyamide components of 50 to 0.00 and melt-spinning. Of producing a polyamide latently crimped yarn.