JP6691857B2 - Polyamide latent crimped yarn and method for producing the same - Google Patents

Description

  The present invention relates to a crimped polyamide crimped yarn in which two types of polyamides are arranged in a laminated type.

As the crimped yarn used for clothing and the like, natural fibers such as cotton and wool whose shape and crimp are reversibly changed by humidity change are well known. Various attempts have been made to obtain crimps for synthetic fibers. For example, a yarn made of a single polymer such as polyester such as polyethylene terephthalate often used for clothing and polyamide 6, such as polyamide 6 and polyamide 12 has almost no crimpability in the fiber itself, and thus the fiber itself is not twisted by false twisting. Crimping is given by giving a torque to. When crimping is imparted by processing such as false twisting, when it is made into a woven or knitted product, surface wrinkles are likely to occur. In order to prevent the occurrence of wrinkles, when the fabric is subjected to hot water treatment, the torque of the crimped yarn due to the processing such as false twisting is reduced, and the stretchability / extension recovery property becomes insufficient, so that a highly stretchable fabric is obtained. Not suitable to get.
There is also a method in which an elastic polymer is used as the crimped yarn to obtain elasticity to obtain a highly stretchable cloth. For example, polyurethane elastic yarn alone has poor dyeability and light resistance, and Since problems such as easy sticking occur, polyamides and the like are usually used after covering.
Further, Patent Document 1 discloses a fiber in which polyamide 12 or polyester is compounded in a side-by-side type or a core-sheath type by using nylon 12 elastomer as an elastic polymer.
On the other hand, various methods for imparting crimpability to fibers by using fibers made of composites of two different kinds of general-purpose polymers as crimped yarns have been studied. For example, a method of combining different resins such as polyester and polyamide into a crimped yarn as a composite fiber, and a method of forming a crimped yarn as a composite fiber in which the same resins having different viscosities are combined are included.
Then, Patent Document 2 describes a polyamide latent crimped yarn having a high crimping property in which a high viscosity polymer is blended with a specific amount of polymethaxylene adipamide to control the viscosities of the high viscosity polymer and the low viscosity polymer. ..

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

However, the polyurethane elastic yarn requires a covering processing cost, resulting in a high cost, which is a cost disadvantage. Further, the one using the copolyamide using the nylon 12 elastomer as in Patent Document 1 is also disadvantageous in cost because the resin is expensive.
In addition, a composite fiber made by combining different polymers such as general-purpose polyesters and polyamides can be manufactured at a low cost to obtain crimps, but is likely to cause resin peeling during spinning / twisting or post-processing. ..
When resins of the same kind but different in viscosity difference are combined, sufficient crimp cannot be obtained, and the elasticity of the fiber itself is not sufficient, and it is difficult to obtain a highly elastic cloth.
Further, although the latent crimped yarn described in Patent Document 2 has a crimping ratio to a certain extent, it is not yet sufficiently stretchable. Further, a latent crimped yarn is required to have a better texture.
Therefore, it is an object of the present invention to solve the above problems and to obtain a polyamide latent crimped yarn having sufficient crimpability and excellent texture without using a covering process or a special copolymer. ..

That is, the present invention relates to a laminating type latent crimped yarn composed of a resin composition (component 1) consisting of polymeta-xylene adipamide and polyamide 6 and a polyamide resin (component 2), which satisfies the following: The first gist is a polyamide latent crimped yarn.
(1) Crimping rate exceeds 50% (2) Drape coefficient shown below is 40% or less
<Calculation of drape coefficient>
1) After opening a tubular knitting sample obtained by a tubular knitting machine with 32 gauge, it is cut into a circle with a radius of 5.0 cm and placed in an environment of 25 ° C. and 27% for 24 hours.
2) The sample with a radius of 5.0 cm is placed on a circular table with a radius of 2.5 cm, and the projected area (S) of the sample is calculated from a photograph taken by a camera from directly above 32 cm of the sample. To do.
3) Shoot the camera from directly above 32 cm, calculate the projected area (S0) of the sample stand, and the projected area (S1) when a thick paper with a radius of 5.0 cm is placed on the sample stand, and calculate the drape coefficient (% ).
Drape coefficient (%) = ((S−S0) / (S1−S0)) × 100
The second gist of the latent latent crimped yarn of polyamide is that the relative viscosity of the resin composition of component 1 is 2.6 to 3.0.
A third aspect of the present invention is a latent polyamide crimped yarn in which the components 1 and 2 are arranged side-by-side.
Also, a latent obtained by laminating two kinds of polyamide components, that is, a resin composition (component 1) composed of polymeta-xylene adipamide and polyamide 6 and a polyamide resin (component 2), melt-composite spinning and stretching. A method for producing crimped yarn, wherein the spinning speed is 1200 to 4000 m /
The method for producing a polyamide latent crimped yarn according to the fourth aspect , which is min, is aged at a temperature of 22 ° C. to 26 ° C., a humidity of 75% to 85% for 24 hours or more, and has a heat setting temperature of 100 to 120 ° C. in the drawing step. and of the subject matter.

According to the present invention, a polyamide crimped yarn having a high crimping property and a good texture can be obtained without performing a covering process or a false twisting process.
Further, high shrinkability can be obtained without using a special polyamide elastomer or other copolymer, which is advantageous in terms of cost.

Hereinafter, the present invention will be described in detail.
The present invention relates to a laminating type latent crimp yarn composed of two kinds of polyamide components composed of a resin composition (component 1) composed of polymeta-xylene adipamide and polyamide 6 and a polyamide resin (component 2). Is.

  From the viewpoint of melt spinning stability, the polyamide 6 used as the component 1 preferably has a relative viscosity of more than 2.2. Further, there is no upper limit to the relative viscosity, but a relative viscosity of up to 3.5 is sufficient from the viewpoint of spinning operation stability.

  The polymethaxylene adipamide used in Component 1 preferably has a relative viscosity of more than 2.1 from the viewpoint of melt spinning stability. More preferably, the relative viscosity is more than 2.6. Further, there is no upper limit to the relative viscosity, but a relative viscosity of up to 3.3 is sufficient from the viewpoint of spinning operation stability.

  From the viewpoint of spinning operability, the water content of the polyamide and polymethaxylene adipamide used as the component 1 of the present invention is preferably 300 ppm or less. It is preferable that the finer the monofilament fiber, the stronger the drying.

  The average relative viscosity of the resin composition of the component 1 of the present invention is preferably 2.6 to 3.0, and preferably 2.7 to 2.9, from the viewpoint of spinnability and high crimp performance. Is more preferable.

  The resin ratio of the polymeta-xylene adipamide and the polyamide 6 used in the component 1 is preferably 35:65 to 70:30, and particularly preferably 45:55 to 55:45. Within this range, the hot water shrinkage is sufficient, and the fiber has high shrinkability and crimpability.

  As the polyamide resin used in the component 2 of the present invention, polyamide 6, polyamide 12, polyamide 66 and the like can be used, but polyamide 6 is particularly preferable.

The polyamide 6 used as the component 2 of the present invention preferably has a relative viscosity of more than 2.2 from the viewpoint of melt spinning stability. It is more preferably 2.4 or more, and particularly preferably a relative viscosity of more than 2.7. Further, there is no upper limit to the relative viscosity, but a relative viscosity of up to 3.5 is sufficient from the viewpoint of spinning operation stability.
From the viewpoint of keeping the crimping ratio high, the relative viscosity of the resin of the component 2 is preferably 2.1 to 3.5, and more preferably 2.3 to 3.0.

  The moisture content of the polyamide resin of component 2 is preferably 300 ppm or less from the viewpoint of spinnability. Further, it is preferable that the finer the monofilament fiber is, the stronger the drying is and the smaller the moisture content is.

  The present invention is a laminating type latent crimp yarn composed of two polyamide components composed of component 1 and component 2.

  The resin ratio (mass ratio) of the components 1 and 2 is preferably 40:60 to 60:40, and particularly preferably 45:55 to 55:45.

  Examples of the method for laminating the latently crimped yarn of the present invention include a method in which Component 1 and Component 2 are separately melted, laminated with a spinneret, and spun to form a composite fiber.

  As the arrangement for adhering the component 1 and the component 2 to each other, the method of arranging the component 1 and the component 2 in a side-by-side type is preferable from the viewpoint of easily exhibiting spinnability and high crimping performance.

  The difference in relative viscosity between the polymers of Component 1 and Component 2 is preferably (Component 1)-(Component 2) =-0.5 to 1.0. Within this range, a latent polyamide crimped yarn having excellent crimpability can be obtained while maintaining the spinning operability.

  The polyamide latent crimped yarn of the present invention has a crimp ratio of more than 50%. When the crimp ratio exceeds 50%, sufficient crimp can be exhibited. Among them, 55% or more is more preferable, and 60% or more is particularly preferable. As a result, it is possible to obtain a high-density cloth that also has elasticity. Then, in post-processing such as dyeing, the latent crimped yarn shrinks, and a high-shrink high-density fabric can be obtained.

  The breaking strength of the polyamide latently crimped yarn of the present invention is preferably 3.2 cN / dtex or more from the viewpoint of maintaining good operability without yarn breakage due to woven or knitting. It is more preferably 4.0 cN / dtex or more.

  The breakage elongation of the latent polyamide crimped yarn of the present invention is preferably 30% or more from the viewpoint of maintaining good operability without causing yarn breakage during woven or knitting. It is more preferably at least 35%.

  The drape coefficient of the cloth made of the latent polyamide crimped yarn of the present invention is 40% or less. It is more preferably 35% or less.

Next, a method for obtaining the latent polyamide crimped yarn of the present invention will be described.
The polyamide latent crimped yarn of the present invention can be obtained by, for example, a two-step method (conventional method) of spinning and twisting.

Hereinafter, a more specific method will be illustrated.
First, the polymeta-xylene adipamide and the polyamide 6 of the component 1 are prepared. Both are mixed by kneading or the like to obtain a resin composition (component 1). Next, a resin of (Component 2) is prepared.
Components 1 and 2 are melt-kneaded, introduced into a spinneret pack, discharged from a nozzle so as to have a predetermined cross section (direction perpendicular to the fiber axis), and melt-spun. Then, after cooling, winding and drawing, a drawn yarn is obtained. In the case of the conventional method, the speed (spinning speed) of the godet roll on which the yarn discharged from the nozzle is first wound is preferably 1200 to 4000 m / min. With such a speed, the elongation rate of the polyamide crimped yarn can be set to 50% or more, and when the cloth is made into a cloth, it is possible to obtain an elastic material or to increase the density.
When the spinning speed is increased, the discharge rate is increased and the shear rate of the nozzle hole is increased. As a result, the molecular chains in the fiber immediately below the nozzle are oriented, and the fiber is wound with a high strain. By further stretching the strained fiber to add molecular chain orientation and store intra-fiber strain, the crimp rate is high and a high degree of crimping can be given, which is highly elastic and highly shrinkable. It is speculated that a latent polyamide latent crimped yarn can be obtained. From this point, the spinning speed is preferably 1200 m / min or more, and particularly preferably 2500 m / min to 3500 m / min.
Before the stretching step, it is preferable to age for 24 hours or more at a temperature of 22 to 26 ° C and a humidity of 75 to 85%. Within this range, the stretching can be performed smoothly, and when the obtained fiber is used as a cloth, it is easy to obtain a soft and soft texture.

  In the conventional method, the spinning temperature is preferably 270 ° C or higher. More preferably, the spinning temperature is 280 ° C or higher. The upper limit is preferably a spinning temperature of about 290 ° C.

  In the conventional method, the heat setting temperature in the stretching step is preferably lower than 120 ° C. More preferably, the heat setting temperature is 110 ° C. or lower, and even more preferably, the heat setting temperature is 100 ° C. or lower. When the heat setting temperature is higher than 120 ° C., the difference in hot water shrinkage between the component 1 and component 2 single yarns becomes small, and the hot water shrinkage percentage of the entire latent crimped yarn also decreases. As a result, crimps are less likely to develop, and the high density and stretchability of the fabric are impaired.

As described above, in the present invention, the component 1 made of the polyamide resin composition and the component 2 made of the polyamide resin are set within a range of a specific relative viscosity difference, and the spinning speed at the time of spinning and the heat in the spinning process are set. By controlling the set temperature to a low level and making it a latent crimped yarn such as a composite fiber in which both components are stuck together, it has excellent strength and elongation and high elasticity that can develop high crimps. A shrinkable polyamide latent crimp yarn can be obtained.

The polyamide latent crimped yarn obtained in this way can maintain an appropriate strength, and thus has good weavability. Further, since the latent crimped yarn of the present invention has high crimpability and drapeability, it is possible to obtain fibers having a higher density and a better texture when subjected to shrinkage processing by weaving. Is possible. Due to such characteristics, it can be expected that the polyester high-density woven fabric has a good texture which is not found.

The present invention will be described in detail below with reference to examples. The present invention is not limited to the examples described below.
The measurement and evaluation of physical properties were performed as follows.

A. Measurement of relative viscosity It is measured using an automatic viscosity measuring device (SS-600-L1 type) manufactured by Shibayama Scientific Machinery Co., Ltd. Using 95.8% concentrated sulfuric acid as a solvent, the polymer is dissolved at a concentration of 1 g / dl, and measurement is carried out in a constant temperature bath at 25 ° C.

B. Measurement of Breaking Strength and Breaking Elongation According to JISL1013, the AGS-1KNG Autograph Tensile Tester manufactured by Shimadzu Corporation was used and measured under the conditions of a sample yarn length of 20 cm and a constant speed tensile test of 20 cm / min. The value obtained by dividing the maximum value of the load on 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. Calculation of crimp ratio Using a measuring instrument manufactured by Asano Kikai Co., Ltd., a fold of 5 revolutions is prepared and bundled doubly. Then, apply a 1/6000 g / d weight and put it in a boiling water bath, soak it in the bath for 30 min, then take it out and let it air-dry for 30 min, then apply a 1/500 g / d weight and the length after 30 seconds (A). Was further measured, a weight of 1/20 g / d was applied, the length (B) after 30 seconds was measured, and the crimp ratio was calculated by the following formula.
Crimp ratio (%) = ((B−A) / B) × 100

D. Calculation of Drape Coefficient A tubular knitting sample was produced using a test tubular knitting machine (NCR-EW) manufactured by Eiko Sangyo Co., Ltd. (gauge number: 32). After opening the obtained cylindrical knit sample, it is cut into a circle having a radius of 5.0 cm. The tubular knit sample cut before the measurement is placed in an environment of 25 ° C. and 27% for 24 hours. A sample having a radius of 5.0 cm was placed on a circular table having a sample stage radius of 2.5 cm, and the projected area (S) of the sample was calculated from a photograph taken by a camera from directly above 32 cm of the sample. Further, the projected area of the sample stand was (S0), and the projected area when a thick paper having a radius of 5.0 cm was placed on the sample stand was (S1), and the drape coefficient (%) was calculated by the following formula.
Drape coefficient (%) = ((S−S0) / (S1−S0)) × 100

E. Texture evaluation The texture was evaluated for the tubular knitting sample used for the calculation of the drape coefficient. The soft and good texture was evaluated as ◯, the slightly hard texture was evaluated as Δ, and the hard texture was evaluated as x.

[Example 1]
Component 1 polyamide with a relative viscosity of 2.9 (polymethaxylene adipamide and polyamide 6 mixed in a blender so that the mass ratio is 50:50) and component 2 (polyamide 6) with a relative viscosity of 2.4 By a conventional method, using a spinning nozzle, melt spinning was performed at a spinning temperature of 280 ° C. and a winding speed (spinning speed) of 2750 m / min so that the mass ratio of component 1: component 2 was 1: 1 and the cross-section of the fiber was side by side. A peanut-type latent crimped yarn was obtained.
The undrawn yarn is aged for 24 hours in an environment of a temperature of 23 ° C. and a humidity of 80%, and then drawn at a drawing speed of 800 m / min, a spindle speed of 7500 rpm, a plate heater temperature of 100 ° C., a draw ratio of 1.6 times, and latent A crimped yarn was obtained.

[Examples 2, 3, 4]
A latent crimped yarn was obtained in the same manner as in Example 1 except that the spinning speed was changed to 3100 m / min, 3500 m / min and 4000 m / min.

[Comparative Example 1]
A latent crimped yarn was obtained in the same manner as in Example 1 except that the relative viscosity of the component 2 polyamide (polyamide 6) was changed to 3.0.

[Comparative Example 2]
A latent crimped yarn was obtained in the same manner as in Example 1 except that the storage temperature and humidity of the yarn before the drawing step were 35 ° C. and 55%.

The production conditions, the fineness, the breaking strength, the breaking elongation, the crimp ratio, the drape coefficient, the temperature / humidity during aging, and the texture evaluation results of the latent crimped yarns obtained in Examples 1 to 4 and Comparative Examples 1 and 2 are shown. , Shown in Table 1.

The latent crimped yarns obtained in Examples 1 to 4 all had a crimping rate of 50% or more, and had high crimpability.
Further, the latent crimped yarns obtained from Examples 1 to 4 and Comparative Examples 1 to 2 were made into a fabric, and the drape property was evaluated. As a result, those obtained from Examples 1 to 4 had a soft texture and a good texture. However, the product obtained from Comparative Example 1 was hard and a good texture was not obtained.
When the latent crimped yarns obtained were woven and dyed, the latent crimped yarns obtained from Examples 1 to 4 were excellent in stretchability, and were woven fabrics having high bulk and good texture. However, when the latent crimped yarns obtained from Comparative Examples 1 and 2 were woven and dyed, the stretchable fabric and the bulkiness were inferior, and the fabric had a hard texture.

Claims (4)

A laminating type latent crimped yarn composed of a resin composition (component 1) comprising polymeta-xylene adipamide and polyamide 6 and a polyamide resin (component 2), comprising the following (1) and (2) Polyamide latent crimped yarn that meets the requirements of.
(1) Crimp ratio exceeds 50% (2) Drape coefficient shown below is 40% or less
<Calculation of drape coefficient>
1) After opening a tubular knitting sample obtained by a tubular knitting machine with 32 gauge, it is cut into a circle with a radius of 5.0 cm and placed in an environment of 25 ° C. and 27% for 24 hours.
2) The sample with a radius of 5.0 cm is placed on a circular table with a radius of 2.5 cm, and the projected area (S) of the sample is calculated from a photograph taken by a camera from directly above 32 cm of the sample. To do.
3) Shoot the camera from directly above 32 cm, calculate the projected area (S0) of the sample stand, and the projected area (S1) when a thick paper with a radius of 5.0 cm is placed on the sample stand, and calculate the drape coefficient (% ).
Drape coefficient (%) = ((S−S0) / (S1−S0)) × 100 The polyamide latent crimped yarn according to claim 1, wherein the resin composition of Component 1 has a relative viscosity of 2.6 to 3.0. The polyamide latent crimped yarn according to claim 1 or 2, wherein the component 1 and the component 2 are arranged side by side. Latent crimp obtained by laminating two kinds of polyamide components, a resin composition (component 1) consisting of polymeta-xylene adipamide and polyamide 6 and a polyamide resin (component 2), melt composite spinning and stretching A method for producing a yarn, which comprises a spinning speed of 1200 to 4000 m / min, aging at a temperature of 22 ° C to 26 ° C and a humidity of 75% to 85% for 24 hours or more, and a heat setting temperature in the drawing step of 100 to. It is 120 degreeC, The manufacturing method of the polyamide latent crimped yarn of any one of Claims 1-3.