JP4639889B2 - Polytrimethylene terephthalate extra fine yarn - Google Patents

Description

  The present invention relates to an ultrafine polytrimethylene terephthalate yarn obtained by elution treatment and excellent in dyeing uniformity suitable for artificial leather and suede-like material.

Conventionally, artificial leather and suede knitted fabric are widely used as household materials and clothing. For these materials, ultrafine yarn having a single fiber fineness of 0.5 dtex or less is often used, and nylon or polyethylene terephthalate is generally used. However, it has been difficult to achieve both softness and color development. On the other hand, polytrimethylene terephthalate (hereinafter referred to as 3GT), which is excellent in softness, easy dyeability, and color development, has attracted attention in recent years, and the emergence of extra fine yarn as artificial leather and suede-like material utilizing the characteristics of 3GT. Was strongly sought after. Ultra-fine yarn made of 3GT has been proposed (see Patent Literature 1 and Patent Literature 2), but is an ultra-fine yarn by direct yarn production, the fineness variation degree U% is bad, and it becomes a dyed spot when dyed, and the uniformity of dyeing It was inferior. In addition, since the yarn is produced with a die having a very small pore diameter, the accumulation of die dirt due to monomers over time reveals adverse effects such as variations in the single fiber fineness within the multifilament, resulting in poor dyeing uniformity. As a result, long-term stability was lacking. In Patent Document 2, in order to obtain an ultrafine yarn of 0.2 denier or less, 3GT of 0.4 to 0.8 having a low intrinsic viscosity is used. In addition, there is a problem that sufficient strength and elongation cannot be realized and the color developability is poor.
JP-A-8-232117 (Claims) Japanese Patent Application Laid-Open No. 11-100721 (Claims)

  The present invention is intended to solve the above-described conventional problems, and provides an ultrafine yarn excellent in color developability and dyeing uniformity using 3GT excellent in softness, easy dyeability and color developability. It is in.

The present invention is achieved by adopting the following items.
(1) and polylactic acid as the eluting component, fiber-forming component as a polytrimethylene terephthalate obtained by elution of the elution component of the composite fibers comprising polytrimethylene terephthalate least 90 mole%, of recurring units of trimethylene terephthalate An ultrafine yarn having an intrinsic viscosity of 0.8 to 2.0, a single fiber fineness of 0.01 to 0.3 dtex, a fineness variation U% of 1.0% or less, and a single fiber fineness variation in a multifilament A polytrimethylene terephthalate ultrafine yarn having a (fineness CV) of 5% or less, a strength of 3.0 to 5.0 cN / dtex, and an elongation of 30 to 60% .

  According to the present invention, it is possible to provide a 3GT ultrafine yarn excellent in color developability and dyeing uniformity which could not be achieved by the prior art.

Hereinafter, the present invention will be described in detail.

  The 3GT ultrafine yarn of the present invention is obtained by elution treatment of a composite fiber. The composite fiber is composed of a non-eluting component (component A) and an elution component (component B), and examples include sea-island type composite fibers and split type composite fibers as shown in FIGS. . Although it is not particularly defined as long as it is divided into a plurality of parts by the elution treatment, it is preferable that the ultrafine yarns after the elution treatment are congruent in obtaining dyeing uniformity. There are no particular restrictions on the number of divisions, and any number of divisions may be used as long as it is within the fineness range defined in the present invention. Specifically, the number of divisions is preferably in the range of 3 to 200.

  Component A, which is a non-eluting component of the composite fiber, is a component constituting an ultrathin yarn after the elution treatment, and is 90% by mole or more of polytrimethylene terephthalate composed of trimethylene terephthalate repeating units.

  Polytrimethylene terephthalate is a polyester obtained using terephthalic acid as the main acid component and 1,3 propanediol as the main glycol component. However, it may contain a copolymer component capable of forming another ester bond at a ratio of 10 mol% or less. Examples of copolymerizable compounds include dicarboxylic acids such as isophthalic acid, cyclohexanedicarboxylic acid, adipic acid, dimer acid, and sebacic acid, while glycol components include, for example, ethylene glycol, diethylene glycol, butanediol, neopentyl glycol, and cyclohexanedimethanol. , Polyethylene glycol, polypropylene glycol and the like can be mentioned, but are not limited thereto.

  Further, titanium dioxide as a matting agent, silica or alumina fine particles as a lubricant, hindered phenol derivatives, coloring pigments and the like as antioxidants can be added as necessary.

  Component B, which is an elution component of the composite fiber, is not particularly defined as long as it is a thermoplastic resin that has a higher alkali weight loss rate than Component A. However, considering the suppression of thermal degradation of 3GT having a melting point lower than that of polyethylene terephthalate, etc. Lactic acid is preferred. Polylactic acid, unlike polyethylene terephthalate copolymerized with an organic metal salt, does not require acid treatment for elution, so there is no discharge of acidic solvent, reducing the environmental burden, and shortening the elution process. Very preferred.

Here, the polylactic acid used in the present invention is a polymer having-(O-CHCH ₃ -CO) _n -as a repeating unit, and refers to a polymer obtained by polymerizing lactic acid or its oligomer. Since lactic acid has two types of optical isomers, D-lactic acid and L-lactic acid, the polymer is poly (D-lactic acid) consisting only of D isomer and poly (L-lactic acid) consisting only of L isomer, and There is polylactic acid consisting of both. The optical purity of D-lactic acid or L-lactic acid in polylactic acid is lowered, crystallization is lowered, and melting point drop is increased. Therefore, the optical purity is preferably 90% or more in order to improve heat resistance. A more preferable optical purity is 93% or more, and a still more preferable optical purity is 97% or more. As described above, the optical purity has a strong correlation with the melting point. The optical purity is about 90%, the melting point is about 150 ° C., the optical purity is 93%, the melting point is about 160 ° C., the optical purity is 97%, and the melting point is about 170 ° C. It becomes.

  In addition to the system in which two types of optical isomers are simply mixed as described above, the two types of optical isomers are blended and formed into a fiber, and then subjected to high-temperature heat treatment at 140 ° C. or higher. A stereo complex in which a racemic crystal is formed is more preferable because the melting point can be dramatically increased.

  The cross-sectional shape of the ultrafine yarn of the present invention is not particularly limited, and includes a round cross-section, a polygonal cross-section such as a triangular cross-section and a flat shape, an alphabet cross-section such as a T-shape, Y-shape, and X-shape, and a star shape Can be mentioned.

  It is important that the ultrafine yarn of the present invention has an intrinsic viscosity of 0.8 to 2.0. When the intrinsic viscosity is less than 0.8, it becomes difficult to produce a fiber having sufficient strength and elongation. A more preferable intrinsic viscosity is 0.9 or more. Moreover, when intrinsic viscosity exceeds 2.0, production stability will also be inferior. A more preferable intrinsic viscosity is 1.5 or less.

  Moreover, the single fiber fineness of the ultrafine yarn is 0.01 to 0.5 dtex. If it is less than 0.01 dtex, the soft feeling is improved, but it is difficult to obtain sufficient color developability, which is not preferable. A more preferable single fiber fineness is 0.03 dtex or more. Further, if the single fiber fineness exceeds 0.5 dtex, it is not preferable because it is not suitable for deployment to a suede-like material or artificial leather. A more preferable single fiber fineness is 0.3 dtex or less.

  Furthermore, the fineness variation degree U% is 1.0% or less. When it exceeds 1.0%, when dyeing is performed after forming a fabric, uneven dyeing becomes noticeable in a streak shape and cannot be practically used. A preferable range of U% is 0.8% or less. Moreover, the single fiber fineness variation (fineness CV) in a multifilament needs to be 5% or less. If it exceeds 5%, the dyeing unevenness becomes noticeable when dyeing after making into a fabric, which is not practical. The variation in single fiber fineness is preferably 3% or less. In order to satisfy these regulations, it is necessary for the ultrafine yarn to be eluted from the above-mentioned composite fiber, and in the direct spinning method, the fineness is so thin that it is easily affected by the turbulence of the airflow due to disturbance. For reasons, it is difficult to obtain a good U%, and it is necessary to use a die having a small hole diameter, so although it is good immediately after the start of spinning, the dispersion of the single fiber fineness increases due to the stain of the die deposited over time. End up.

The ultrafine yarn of the present invention preferably has a strength of 3.0 to 5.0 cN / dtex. In post-processing such as weaving and dyeing, the strength is preferably 3.0 cN / dtex or more because of the effect of improving yarn breakage, fluff and the like. A more preferable strength is 3.3 cN / dtex or more. When considering optimization of productivity due to production conditions such as draw ratio, the strength is preferably 5.0 cN / dtex or less. More preferable strength is 4.5 cN / dtex or less. Further, the elongation is preferably 30 to 60%. An elongation of 30% or more is preferable because the color developability is good. More preferable elongation is 35% or more, more preferably 38% or more. Further, it is preferable that the elongation is 60% or less because the strength can be optimized and problems such as yarn breakage and fluff are easily avoided. A more preferable elongation is 55% or less.
The shrinkage performance of the ultrafine yarn of the present invention is appropriately in the range of 9 to 20% in boiling shrinkage, 12 to 30% in dry heat shrinkage at 160 ° C., and 0.2 to 0.5 cN / dtex in heat shrinkage stress peak value. It is suitable for obtaining a soft feeling and color developability. In addition, the initial tensile resistance is in the range of 20 to 40 cN / dtex, which is appropriate for obtaining an appropriate soft feeling.

  Next, the manufacturing method of the ultrafine yarn described above is demonstrated.

  The composite fiber for obtaining the ultrafine yarn of the present invention is produced by any known method, but the melt spinning method is the most excellent in view of the stability and productivity of the composite structure. In melt spinning the composite fiber, 3GT as a non-eluting component is preferably melted at 240 to 280 ° C. In the melting, a pressure melter method and an extruder method can be mentioned, and melting by an extruder is preferable from the viewpoint of uniform melting and retention prevention. On the other hand, the polymer as an elution component is preferably melted at a temperature 10 to 40 ° C. higher than the melting point of the polymer. When polylactic acid is used as an elution component, melting at 200 to 240 ° C. is preferable using an extruder as in 3GT. Separately melted polymers pass through separate pipes, weigh and then flow into the base pack. Under the present circumstances, it is preferable that piping passage time is 5 to 30 minutes from a viewpoint of suppressing thermal deterioration. The polymer that has flowed into the pack is merged by the die, and is combined into a form such as a sea-island type or a split-fiber type by a known technique and discharged from the die. In this case, the polymer temperature is suitably 240 to 270 ° C. when polylactic acid is used as an elution component. If it is this range, the fall of productivity and the coloring property by a heat degradation and the fall of a soft feeling can be prevented.

The polymer discharged from the die is cooled and solidified, and after the oil is applied, it is taken out.
The take-up speed is possible at any speed of 500 to 6000 m / min. In a method in which an undrawn yarn called a two-step method is wound once and then drawn, the take-up speed is 500 to 2000 m / min. Further, the film may be taken up in a region up to 4000 m / min, and the partially oriented yarn may be wound once and then drawn. When obtaining a partially oriented yarn, a method of performing a heat treatment before winding and accelerating crystallization by heat and then winding is preferred for obtaining uniform physical properties. On the other hand, in the one-step method, there is a method of obtaining drawn yarn at a speed at a speed of 4000 to 6000 m / min. Also in this case, it is effective to perform heat treatment before winding. Furthermore, a method called a direct spinning drawing method is also included. This method is a method of taking up in an undrawn yarn or partially oriented yarn region of 500 to 4000 m / min and winding up after preheating, drawing, and heat treatment to obtain a drawn yarn without winding up once. In the spinning and drawing methods mentioned above, the draw ratio is suitably set so that the drawn yarn elongation falls within the range specified in the present case. Further, in any of the spinning and drawing processes, it is possible to perform entanglement using a known entanglement device before winding. If necessary, it is possible to increase the number of confounding by giving multiple times. Furthermore, it is also possible to add an oil agent immediately before winding.

  The composite yarn produced as described above is treated in an acid solution, if necessary, and then eluted in an alkaline solution to form an ultrafine yarn. In general, the elution treatment is carried out after making the fabric, but it is not limited to this. When polylactic acid is used as an elution component, the treatment with an acid solution is not necessary, and an alkaline solution can be biodegraded, which is preferable in terms of productivity and environmental compatibility. The alkali elution treatment can be eluted using an aqueous sodium hydroxide solution according to a conventional method. It is preferable to use an aqueous sodium hydroxide solution heated to 80 ° C. or higher because the elution time is shortened.

  The ultra-fine yarn obtained is suitable for suede-like materials and artificial leather, and is also useful as a high-density fabric that combines windproof properties, creating a uniform surface feel that produces a unique soft feeling, color development, and uniform dyeability. Is obtained. Applications that can be applied are not limited to this, and when polylactic acid is used as an elution component, treatment with an acid solution is not necessary, so it can be woven or knitted with natural fibers such as cotton. In addition to woven and knitted fabrics, it can also be applied to materials.

Hereinafter, although an example is given and explained concretely, the present invention is not limited to an example. In addition, the main measured value of the Example was measured with the following method.
(1) Intrinsic viscosity Intrinsic viscosity [η] is a value determined based on the following defining formula.

Ηr in the definition formula is a value obtained by dividing the viscosity at 25 ° C. of a diluted solution of 3GT dissolved in O-chlorophenol having a purity of 98% or more by the viscosity of the solvent itself measured at the same temperature. Is defined. C is the solute weight value in grams in 100 ml of the solution.
(2) U%
Measurement was performed in the normal mode while feeding the yarn at a speed of 200 m / min for 1 minute using a Zellerweger USTER TESTER 4-CX.
(3) Single fiber fineness variation (fineness CV)
A cross-sectional photograph of all the single filaments of the multifilament was taken, the single fiber fineness was calculated from the cross-sectional area, and the standard deviation of the total single fiber fineness of the multifilament was divided by the average single fiber fineness. The cross-sectional image was taken and calculated for arbitrary points and 5 points, and the average value was defined as the single fiber fineness variation (fineness CV).
(4) Strength and elongation Measured according to JIS L1013 (1999).
(5) Boiling water shrinkage Boiling water shrinkage (%) = {(L0−L1) / L0} × 100
L0: skein of the original yarn 1 m × 10 times, skein length with a measurement load of 0.029 cN / dtex L1: the raw yarn is treated with boiling water at 100 ° C. for 15 minutes under no load, and air-dried After that, the skein length when a measurement load of 0.029 cN / dtex was applied (6) Uniform dyeing uniformity Samples immediately after the start of yarn production (Sample A) and 24 hours after the start of yarn production (Sample B) were knitted and tetraseal as a dye Navy Blue SGL 0.275% owf, Tetrocin PE-C 5.0% owf as an auxiliary agent, Nikka Sun Salt # 12001.0% owf as a dispersing agent, 50 ° C. for 15 minutes at a bath ratio of 1: 100, and further 90 ° C. Staining was performed at 20 minutes. The sample after dyeing was subjected to a sensory test for uneven dyeing and a dyeing difference between samples A and B and evaluated in three stages. In addition, the pass level is more than ○.

◯: Excellent ◯: Excellent ×: Poor uniformity (7) Colorability (7) Using a dyed sample similar to (6), a three-stage evaluation was made by sensory test. In addition, the pass level is more than ○.

○○: Very good ○: Excellent ×: Equivalent to polyethylene terephthalate fiber Example 1
Poly-L-lactic acid with an optical purity of 98.0% and homo-3GT with an intrinsic viscosity of 1.1 were melted at 210 ° C and 250 ° C, respectively, using an extruder, and then weighed with a pump. In order to form a sea-island type composite form as shown in FIG. The composite weight ratio was 3GT7 with respect to polylactic acid 3. The passage time of each polymer for piping was 20 minutes for polylactic acid and 11 minutes for 3GT. The yarn discharged from the die is cooled and applied with an oil agent, taken up by a hot roller heated to 55 ° C. at a speed of 2700 m / min, and heated to 150 ° C. at a speed of 4300 m / min without being wound once. It was drawn around a hot roller and stretched and heat set. Further, two godet rollers were drawn around at 4200 m / min, and then wound up at 4080 m / min to obtain 8 island-island type composite yarns of 72 dtex-36 filaments. The tension at the winder inlet was 0.13 cN / dtex. The obtained composite yarn was treated in a 3% aqueous sodium hydroxide solution at 25 ° C. until the polylactic acid was completely eluted to obtain ultrafine yarn. The results of physical properties and texture evaluation of the ultrafine yarn are shown in Table 1, and were excellent in dyeing uniformity and color development.

Example 2
A 70 island sea-island composite fiber was obtained by spinning the yarn under the same conditions as in Example 1 except that it was wound at 4070 m / min using a 70-island sea-island composite fiber base. . Elution treatment was performed in the same manner as in Example 1 to obtain ultrafine yarn. It was excellent in dyeing uniformity and color development.

Example 3
Except for using a base for 140 islands of sea-island type composite fibers, yarn was produced under the same conditions as in Example 1,
A sea-island type composite fiber of 140 islands of 56 dtex-12 filaments was obtained. Elution treatment was performed in the same manner as in Example 1 to obtain ultrafine yarn. Although it was a super extra fine thread, the dyeing uniformity and color development were good.

Examples 5-6
As shown in Table 1, yarns were produced under the same conditions as in Example 1 except that the intrinsic viscosities of 3GT were 0.9 and 1.5, respectively, and eight islands of 72 dtex-36 filaments were obtained. It was. It was excellent in dyeing uniformity and color development.

Example 7
A composite yarn was obtained in the same manner as in Example 1 except that the base was changed to a 6-split split fiber composite fiber as shown in FIG. Elution treatment was performed in the same manner as in Example 1 to obtain ultrafine yarn. A fabric having a unique surface feeling that is excellent in both dyeing uniformity and color developability and not seen in a round cross section was obtained.

Comparative Example 1
A homo 3GT having an intrinsic viscosity of 1.1 was melted at 260 ° C. with an extruder, weighed with a pump, and discharged from the die at a temperature of 260 ° C. After cooling, an oil agent was applied and wound up at a speed of 1200 m / min to obtain an undrawn yarn. The obtained undrawn yarn was pre-heated at 50 ° C. with a hot roll, drawn at a draw ratio of 2.5 times, and subjected to a hot roll heat treatment at 120 ° C., wound up at 800 m / min, and extremely fine with a 56 dtex-140 filament. I got a thread. The results of physical properties and texture evaluation of the obtained ultrafine yarn are as shown in Table 2. U% is poor, and single fiber variation over time is large, so that the uniformity of dyeing is poor, the elongation is low, and the color developability. It was also inferior.

Comparative Example 2
An attempt was made to obtain a 56 dtex-180 filament ultrafine yarn under the same conditions as in Comparative Example 1, but the evaluation was not possible because the yarn-making property and drawability were poor and the sample could not be collected.

Comparative Example 3
An ultrafine yarn was obtained by producing yarn under the same conditions as in Comparative Example 1 except that 3GT having an intrinsic viscosity of 0.6 was used. The strength and elongation were low, and the dyeing uniformity and color developability were poor.

Comparative Example 4
Although yarn was produced under the same conditions as in Example 1, turbulent wind was forcibly applied in the cooling zone. The obtained ultrafine yarn had a low U%, and streaky dyeing unevenness was confirmed.

An example of a sea-island type composite fiber cross section is shown. An example of a split fiber type composite fiber cross section is shown.

Explanation of symbols

1 Region consisting of polymer based on polytrimethylene terephthalate (non-eluting component)
2 Area consisting of easily eluting polymers (eluting components)

Claims (1)

And polylactic acid as the eluting component, in polytrimethylene terephthalate microfibers obtained by elution of the elution component of the composite fibers comprising polytrimethylene terephthalate comprising repeating units of 90 mol% or more trimethylene terephthalate as the fiber-forming component The intrinsic viscosity is 0.8 to 2.0, the single fiber fineness is 0.01 to 0.3 dtex, the fineness variation U% is 1.0% or less, and the single fiber fineness variation in the multifilament (fineness CV ) Is 5% or less, the strength is 3.0 to 5.0 cN / dtex, and the elongation is 30 to 60% .

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