JP4221015B2 - Split type composite fiber and manufacturing method thereof - Google Patents

Description

  The present invention relates to a split type composite fiber suitable for a high-density woven or knitted fabric, which comprises a polyester component and a polyamide component, and is chemically split with a swelling agent after weaving and knitting, and a method for producing the same.

Conventionally, there have been many proposals regarding a composite fiber containing polyester / polyamide as a component and a high-density woven or knitted fabric made of the composite fiber. For example, Patent Literature 1 and Patent Literature 2 propose a method of weaving and then treating with a benzyl alcohol emulsified aqueous solution to swell and shrink the polyamide component to split the polyester component and the polyamide component. For high-density plain woven fabric, a similar method is proposed in Patent Document 3.
Japanese Examined Patent Publication No. 53-35633 JP-A-60-215869 Japanese Examined Patent Publication No. 62-8535

  In any case, the split type composite fiber is a so-called one in which polyethylene terephthalate having a general intrinsic viscosity of 0.61 to 0.63 is used as one component, the undrawn yarn is wound once in the spinning step, and drawn in the drawing step. It is manufactured by the conventional method (hereinafter referred to as the convex method).

  In the case of producing by this method, in order to make the chemical splitting property with the swelling agent uniform throughout the entire woven or knitted fabric, it was necessary to perform an aging treatment for a certain period of time under a certain temperature and humidity in an undrawn yarn state. . This method has a problem in that the swelling splitting property changes depending on the leaving period of the undrawn yarn, and the production efficiency is also poor.

  On the other hand, as a method for increasing production efficiency, for example, a direct spinning drawing method (hereinafter referred to as an SPD method) in which drawing is performed without winding once after spinning, and a high-speed spinning method are known as known techniques.

  However, in the case of components having different properties such as polyester / polyamide, such as the composite fiber, the splitting performance is extremely poor and does not split evenly or not at all if chemical splitting with a swelling agent is performed. Therefore, it is difficult to obtain a high-quality high-density woven or knitted fabric.

  An object of the present invention is to obtain a split-type composite fiber having a uniform splitting property suitable for high-quality high-density woven or knitted fabrics, which eliminates the disadvantages of the prior art, and further, weaving or knitting. When chemical splitting treatment is performed later with a swelling agent, a polyester component and a polyamide component are uniformly divided, and an object is to provide a split type composite fiber that is efficiently produced at low cost.

  The inventors of the present invention have arrived at the present invention as a result of intensive studies. That is, if it is a split type composite fiber consisting of a polyester component and a polyamide component, and the intrinsic viscosity in the fiber of the polyester component is 0.500 or more and less than 0.600, chemical treatment with a swelling agent is performed after weaving and knitting. A polyester component and a polyamide component are uniformly split.

According to the present invention, the polyester component and the polyamide component are uniformly divided when subjected to chemical splitting treatment with a swelling agent, both of those manufactured by the direct spinning drawing method (SPD method) and those manufactured by the convex method. A mold composite fiber can be obtained.
Split-type composite fibers that can be divided uniformly in this way are suitable for high-quality woven and knitted fabrics, because when they are woven or knitted fabrics such as suede knitted fabrics, warp and wefts are eliminated by uniform splitting. It becomes.

  The present invention is described in detail below. Examples of the polyester component of the present invention include polyethylene terephthalate, polytrimethylene terephthalate, polyethyleneoxybenzoate, polybutylene terephthalate, and copolyesters containing these as components. Polyethylene terephthalate is generally used and preferable.

  On the other hand, as the polyamide component, for example, nylon 6, nylon 66, nylon 4, nylon 7, nylon 11, nylon 12, polymetaxylene adipamide and the like are known, but nylon 6 is preferable from the viewpoint of versatility. .

  The intrinsic viscosity of the polyester component, which is the most important point of the present invention, in the fiber needs to be 0.500 or more and less than 0.600. If it is this range, even if it does not perform an aging process of an undrawn thread | yarn by a convex method, it splits uniformly with a swelling agent, and even when manufactured by the SPD method which is hard to split, it splits uniformly. Also, the spinning operability is good.

  If it is less than 0.500, the yarn breakage at the spinning stage increases, the physical properties of the fiber are lowered, and the yarn breakage is liable to occur during weaving and knitting, and the product itself lacks the feeling of swelling. If it is 0.600 or more, in the case of the convex method, if the undrawn yarn after spinning is not subjected to an aging treatment for a certain period, the splitting property becomes non-uniform in the chemical splitting treatment with the swelling agent. In the case of the SPD method, no splitting is performed.

There are, for example, the following three methods for controlling the intrinsic viscosity in the fiber of the polyester component. (1) Manufactures polyethylene terephthalate chips having an intrinsic viscosity of 0.500 to 0.600 and a moisture content of 15 to 30 ppm after drying (2) Clothing having an intrinsic viscosity of 0.600 or more and 0.700 or less The general-purpose polyethylene terephthalate chip suitable for the application is dried at a water content of 50 to 100 ppm, and the viscosity is lowered by melt extrusion during spinning (3) The intrinsic viscosity similar to (2) is 0.600 or more and 0.700 or less After drying a general-purpose polyethylene terephthalate chip suitable for clothing use, the water content is set to about 15 to 30 ppm, and the temperature at the time of melt extrusion is increased to lower the viscosity. For example, it is to raise the temperature up to 300 to 320 ° C., where the melt extrusion is usually performed at 290 to 295 ° C.
In any case, the polyester component intrinsic viscosity in the composite fiber may be within the range of the present invention.

  The relative viscosity of the polyamide component in the fiber is not particularly limited, but it is preferably in the range of 2.0 to 3.5 from the viewpoint of spinning operation and yarn physical properties.

  The ratio of the polyester component to the polyamide component is usually 5/1 to 1/5 (volume ratio), preferably 3/1 to 1/3 (volume ratio). If it is this range, if a splitting process will be performed with a swelling agent, a polyamide component will fully swell, and it will shrink | contract by the subsequent water washing process, and it will become easy to divide | segment a polyester component and a polyamide component uniformly.

  The cross-sectional shape of the composite fiber is compatible with each other as proposed in JP-B-62-2535, JP-A-52-27822, JP-A-61-282445, and JP-A-7-97742. A product composed of a combination of poor polymers can be used, an example of which is shown in FIG. Among these, a radial product in which a polyester component and a polyamide component are alternately arranged is preferable because the polyamide component is extremely swelled and contracted and easily split.

  The production method of the split-type conjugate fiber of the present invention is not particularly limited as long as it is ordinary melt spinning, and is a winding method in which unstretched yarn is wound up after spinning and stretched in a stretching process, or once unstretched yarn is stretched. The SPD method of winding after stretching without winding is common, but it is most preferable to manufacture by the SPD method in consideration of production efficiency and cost efficiency.

  The single fiber fineness of the composite fiber is preferably about 0.5 to 10 dtex, more preferably 1 to 5 dtex. Within this range, the spinning operability is good, and the texture of the microfiber, such as the feeling of swelling and raising, is good. Moreover, the fineness of each fibril after splitting and fibrillation of each component constituting the composite fiber is preferably 0.02 to 0.5 dtex. The fineness of each component after splitting and fibrillation may be the same or different.

  After weaving and knitting the split type composite fiber, chemical splitting treatment is performed with a swelling agent, and the polyamide component is swollen with the swelling agent to split the polyester component and the polyamide component. Thereafter, the swelling agent escapes from the polyamide component and shrinks by washing with water, thereby imparting a swelling feeling and high-density performance peculiar to microfibers. Examples of the swelling agent include benzyl alcohol, β-phenylethyl alcohol, phenol, m-cresol, formic acid, acetic acid and the like as described in JP-B-62-2535. Moreover, it is suitable to use the aqueous solution or aqueous emulsion. Among them, the method using an aqueous emulsion of benzyl alcohol is excellent in terms of the shrinkability and fibrillation effect of the woven or knitted fabric and the ease of handling.

  Hereinafter, the present invention will be described in more detail by way of examples. The characteristic values in the following examples are measured by the following methods.

(1) Intrinsic viscosity of polyester component [η]
When spinning the split-type composite fiber, the discharge of the polyamide component was temporarily stopped, and the polyester component discharged yarn extruded from the spinneret was collected as a sample. Alternatively, it can be measured by dissolving the collected composite fiber with the following solvent and then filtering off the undissolved polyamide component. The measurement was carried out by the Ubbelohde method at 20 ° C. in a mixed solvent of phenol / tetrachloroethane = 6/4 (weight ratio).

(2) Relative viscosity of polyamide component ηrel
When spinning the split-type composite fiber, the discharge of the polyester component was temporarily stopped, and the released yarn of the polyamide component extruded from the spinneret was collected and used as a sample. The measurement was carried out at 25 ° C. in a conventional manner after dissolving in a polymer concentration of 1 g / dl using a concentrated sulfuric acid solvent.

(3) Spinning operability Split type composite fibers are spun by the Convex method or SPD method, and those with good operability with few bobbin ratios with a complete bobbin rate of 85% or more after one week of spinning. The case where there were many cuts and the complete bobbin rate was less than 85% and the operability was poor was evaluated as x.

(4) Splitting properties Using a single-piece cylindrical knitting machine (CR-B) manufactured by Koike Machinery Co., Ltd. with 280 needles, a split-type composite fiber cylindrical knitting sample was prepared, and an aqueous emulsion of 6% benzyl alcohol ( (Emulsifier: Nikka Chemical Sanmor BK20 concentration 0.6%) was subjected to split fiber treatment. By observing the tube knitted fabric after air drying, a product with good splitting property was evaluated as “◯”, a partly split but a defective product was evaluated as “Δ”, and a product that was not split at all was evaluated as “x”. If the splitting property is good by this method, the splitting property is uniform even in a high-density woven or knitted fabric, and a high-quality suede knitted fabric can be obtained. On the other hand, if the method is not defective or not split, warps and wefts are generated in the high-density woven or knitted fabric, resulting in a product with poor quality.

Example 1
Polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.629 after drying as a polyester component are melted at 320 ° C., and nylon 6 chips with a relative viscosity of 2.65 after drying as a polyamide component are melted at 290 ° C. , PET / nylon 6 volume ratio = 2/1, extrude from the composite spinneret, apply oil after cooling, take-up at a peripheral speed of 800 m / min (84 ° C.) of the first goded roller (GR1), then second Radial splitting type composite fiber (PET / Nylon) described in FIG. 1c of 56 dtex / 25 filament by a normal SPD method that leads to a circumferential speed of 3200 m / min (120 ° C.) of the Goded roller (GR2) and stretches between GR1 and GR2. 6 volume ratio = 2/1). When the intrinsic viscosity of PET in the fiber was measured from the discharged yarn collected at the time of extrusion from the spinneret, the results shown in Table 1 were obtained. Moreover, as for the relative viscosity of nylon 6, the results shown in Table 1 were obtained from samples collected by the same method. When a split knitted sample was prepared using this split-type composite fiber and then subjected to a swelling split treatment with a 6% aqueous solution of benzyl alcohol, the splitting property was good as shown in Table 1.

Example 2
Polyester terephthalate (PET) chips with an intrinsic viscosity of 0.578 after drying as a polyester component are melted at 290 ° C, and nylon 6 chips with a relative viscosity of 2.65 after drying as a polyamide component are melted at 280 ° C. Except that, split-type conjugate fibers were obtained by the SPD method in the same manner as in Example 1. The viscosity of each component in the fiber was measured in the same manner as in Example 1, and the results shown in Table 1 were obtained. The intrinsic viscosity of PET was within the range of the present invention, and the spinning operability and splitting property were good as shown in Table 1.

Example 3
Polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.629 after drying as a polyester component are melted at 320 ° C., and nylon 6 chips with a relative viscosity of 2.95 after drying as a polyamide component are melted at 280 ° C. Except for the above, split-type conjugate fibers were obtained by the SPD method in the same manner as in Example 1. The viscosity of each component in the fiber was measured in the same manner as in Example 1, and the results shown in Table 1 were obtained. The intrinsic viscosity of PET was within the range of the present invention, and the spinning operability and splitting property were good as shown in Table 1.

Example 4
Polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.530 after drying as a polyester component are melted at 290 ° C., and nylon 6 chips with a relative viscosity of 2.60 after drying as a polyamide component are melted at 280 ° C. Except for the above, split-type conjugate fibers were obtained by the SPD method in the same manner as in Example 1. The viscosity of each component in the fiber was measured in the same manner as in Example 1, and the results shown in Table 1 were obtained. The intrinsic viscosity of PET was within the range of the present invention, and the spinning operability and splitting property were good as shown in Table 1.

Example 5
Polyethylene terephthalate (PET) chips having an intrinsic viscosity of 0.629 after drying as a polyester component are melted at 310 ° C., and nylon 6 chips having a relative viscosity of 2.95 after drying as a polyamide component are melted at 280 ° C. Except for the above, split-type conjugate fibers were obtained by the SPD method in the same manner as in Example 1. The viscosity of each component in the fiber was measured in the same manner as in Example 1, and the results shown in Table 1 were obtained. The intrinsic viscosity of PET was within the range of the present invention, and the spinning operability and splitting property were good as shown in Table 1.

Example 6
Using the same tip as in Example 2, the undrawn yarn was wound at a spinning speed of 1000 m / min by the convex method. The viscosity of each component in the fiber is as shown in Table 1. Then, when it extended | stretched by the extending | stretching process, without carrying out an aging process, the splitting property was favorable.

Comparative Example 1
Polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.629 after drying as a polyester component are melted at 290 ° C., and nylon 6 chips with a relative viscosity of 2.95 after drying as a polyamide component are melted at 280 ° C. Except for the above, split-type conjugate fibers were obtained by the SPD method in the same manner as in Example 1. The intrinsic viscosity of PET in the fiber was 0.610, which was outside the scope of the present invention. The spinning operability was good as shown in Table 1, but when splitting with an aqueous benzyl alcohol emulsion, splitting was not performed at all.

Comparative Example 2
Polyethylene terephthalate (PET) chips with an intrinsic viscosity of 0.530 after drying as a polyester component are melted at 310 ° C., and nylon 6 chips with a relative viscosity of 2.95 after drying as a polyamide component are melted at 280 ° C. Except for the above, split-type conjugate fibers were obtained by the SPD method in the same manner as in Example 1. The intrinsic viscosity of PET in the fiber was 0.491, which was outside the scope of the present invention. Although the benzyl alcohol splitting property of the composite fiber was good, there were many yarn breaks in the spinning process, and the operability was poor.

Comparative Example 3
The same tip as in Comparative Example 1 was used and melt-extruded under the same conditions, and then the undrawn yarn was once wound at a spinning speed of 1000 m / min by the convex method and drawn in the drawing step without aging treatment. When the split knitting sample was split, the splitting portion and the non-split portion were mixed, and the splitting property was poor.

The example of the cross-sectional shape of the composite fiber which can be used for this invention is shown.

Explanation of symbols

A Polyester component B Polyamide component

Claims (3)

A woven or knitted fabric comprising a polyester component and a polyamide component, wherein the polyester component is split split composite fiber made of polyethylene terephthalate having an intrinsic viscosity of 0.500 or more and less than 0.600 by treating with a swelling agent . The split type composite fiber according to claim 1, wherein the polyester component and the polyamide component are alternately arranged in the cross section of the fiber. After weaving knitting a splittable conjugate fiber poles limit viscosity of the polyethylene terephthalate and the polyamide component is less than 0.500 or 0.600, Wari繊polyethylene terephthalate and a polyamide component swell the polyamide component at a swelling agent A method for producing a knitted or knitted fabric characterized by comprising :

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