JP2006045735A - Acetate conjugated spun fiber and its production method and its woven or knitted fabric - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an acetate fiber which has an effect for improving uniform dyeability and hand from a boiling condition to high pressure high temperature conditions and simultaneously gives a sense of gloss, and to provide a woven or knitted fabric thereof. <P>SOLUTION: This acetate conjugated spun fiber whose cross section has a three layer-bonded structure comprising two triacetate layers and a diacetate layer nipped between the two triacetate layers is characterized by having fine wrinkles on the surface of the fiber in a direction approximately perpendicular to the axis of the fiber and having a larger dye surface coverage by ≥15% than that of a fiber comprising 100% triacetate, when dyed in boiling water. And a woven or knitted fabric comprising the acetate conjugated spun fibers. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a cellulose acetate fiber having improved texture, dyeability and color developability from the fiber, a method for producing the same, and a woven or knitted fabric from the fiber.

Cellulose diacetate fiber is preferably used as a fiber material for clothing because it has moderate hygroscopicity and dry texture, and is excellent in color development. However, when the cellulose diacetate fiber is subjected to a high-temperature dyeing treatment at 100 ° C. or higher, the dye discharge phenomenon occurs, and as a result, it is difficult to dye deeply, and the color developability is likely to decrease. It is difficult to make a composite material for clothing by mixing with a polyester fiber or the like that is subject to temperature.
On the other hand, cellulose triacetate fibers are significantly more hydrophobic than viscose rayon, that is, less swellable in water, and since they are obtained by a dry spinning method, there is almost no micelle spacing, so It is difficult to disperse and adsorb, and does not exhibit sufficient dyeability with respect to direct dyes or ionic dyes. However, cellulose triacetate fiber has high plasticity, and setting the dyeing temperature requires careful consideration from the viewpoint of the physical properties of the fiber and the texture, and it is important to achieve level dyeing especially from low temperature dyeing around 100 ° C. It is.

  For this reason, by making these cellulose diacetate components and cellulose triacetate components into composite spun fibers, it has been practiced to improve the dyeing properties by combining both properties. For example, Patent Literature 1 discloses a three-layer bonded composite spun fiber in which a diacetate component is disposed in an intermediate layer and a triacetate component is disposed outside the intermediate layer.

JP 2001-55629 A

However, in this means, the orientation of the skin layer of the triacetate component is not different from that of ordinary triacetate fiber, so that it is not changed in terms of darkness, and the normal acetate fiber is oriented in the fiber axis direction. Since the folds hardly appear on the surface of the triacetate component, there is a problem that the texture specific to triacetate cannot be obtained sufficiently.
Accordingly, an object of the present invention is to solve such conventional problems and provide an acetate fiber having a glossy feeling while having an effect of improving uniform texture and texture from boiling water conditions to high pressure and high temperature conditions. It is what.

The present invention is a composite spun fiber in which the fiber cross section is composed of a three-layer bonded structure in which diacetate is sandwiched between triacetates, and at least a part of diacetate is exposed on an arbitrary surface of the fiber composed of triacetate, The acetate composite spun fiber has fine folds in a direction substantially perpendicular to the fiber axis, and has a dye adsorption rate of 15% or more higher when dyed with boiling water than a fiber made of 100% triacetate.
Furthermore, the present invention relates to a method for producing an acetate composite spun fiber, wherein dry spinning is performed on a composite spinning stock solution forming a three-layer joint structure in which diacetate is sandwiched between triacetates under conditions satisfying the following formulas (1) to (2): It is in.
(1) 0.15 <Vf / Vj <0.60
(2) 1000 <Vj <2000
(Where Vf is the take-up speed of the spun yarn (m / min), Vj is the discharge linear speed (m / min) from the spinning nozzle of the spinning stock solution, and Vj is (the amount of spinning stock discharged / the spinneret (Total pore area))
Furthermore, this invention exists in the woven / knitted fabric containing the acetate composite spun fiber of this invention.

  According to the present invention, it is possible to obtain acetate fibers having uniform dyeability from boiling water conditions to high pressure and high temperature conditions, an effect of improving the texture, and glossiness, and woven or knitted fabrics thereof.

Hereinafter, preferred embodiments of the present invention will be specifically described.
The acetate composite spun fiber of the present invention has a three-layer bonded structure in which the diacetate is sandwiched between triacetates in the fiber cross section, and at least a part of the diacetate forming the intermediate layer is formed on the fiber surface made of triacetate. Exposed diacetate and triacetate bonded composite spun fibers.
An example of a cross section of the acetate composite spun fiber of the present invention is shown in FIG. In FIG. 1, 1 is a tricetate component, 2 is a diacetate component, and 3 is a fine crease provided on the fiber surface in a direction perpendicular to the fiber axis.
In a composite spun fiber composed of diacetate and triacetate, if the diacetate is exposed in a large proportion on the fiber surface, the dye discharged from the diacetate component dyes the triacetate component when dyed under high pressure and high temperature conditions. Since the diacetate component is decolored, that is, lightly colored, the entire fiber bundle does not appear dark, so the object of the present invention cannot be achieved with a simple joining structure.
In the present invention, it is important that at least a part of the diacetate component 2 sandwiched between the triacetate components 1 and 1 is exposed on the fiber surface. At the same time as it is dyed, it is hardly dyed on triacetate, so it is difficult to produce a product with an uneven amount of dyeing on the triacetate component. In addition, the dye discharged from diacetate is gradually dyed at high dyeing temperatures. An effect will also be expressed. In a core-sheath type composite spun fiber in which the core component is diacetate and the sheath component is triacetate, leveling of the triacetate component by such diacetate component cannot be obtained.

In the present invention, it is characteristic and important that the dye adsorption rate at the time of boiling water dyeing is 15% or more larger than that of a fiber made of 100% triacetate. If this is less than 15%, the amount of dyeing to diacetate at low dyeing temperature is small, and further, the effect of slow dyeing at high dyeing temperature cannot be obtained, so the dyeing amount to triacetate component becomes non-uniform. .
Furthermore, in the present invention, it is important to give fine creases on the fiber surface in a direction substantially perpendicular to the fiber axis by reducing the degree of orientation of the skin layer, thereby increasing the amount of dyeing to the skin layer, An effect excellent in color developability can be obtained, and further an effect of improving the texture can be obtained. At this time, by forming a three-layer joint structure in which diacetate is sandwiched between triacetates whose fiber cross-sectional shape is divided into two layers, folds peculiar to acetate fibers are not easily generated, and therefore uneven folds of folds are unevenly raised. It is possible to solve the problem that no gloss occurs and glossiness decreases.

As a method for producing the above-described acetate composite spun fiber of the present invention, a known joining type composite spinning apparatus may be used. A spinning stock solution in which diacetate and triacetate are combined in a three-layer joining type is expressed by the following formulas (1) to ( It is preferable to perform dry spinning under conditions that satisfy 2).
(1) 0.15 <Vf / Vj <0.60
(2) 1000 <Vj <2000
(Where Vf is the take-up speed of the spun yarn (m / min), Vj is the discharge linear speed (m / min) from the spinning nozzle of the spinning stock solution, and Vj is (the amount of spinning stock discharged / the spinneret (Total pore area))
That is, in the dry spinning method of acetate, it is important to adopt conditions such that the shrinkage behavior in the drying and solidifying process is greatly generated in the fiber axis direction, and the skin layer formed directly under the discharge of the spinning nozzle has a small orientation, In the further drying shrinkage process, as the shrinkage in the fiber axis direction progresses, the skin layer is solidified while being gathered, so that minute creases can be generated on the fiber surface in a direction substantially perpendicular to the fiber axis.
As the spinning condition, when Vf / Vj ≧ 0.60 in the above formula (1) and Vj ≦ 1000 in the formula (2), the shrinkage behavior of the obtained composite fiber in the axial direction cannot be obtained, and the formula (1) When Vf / Vj ≦ 0.15 and Vj ≧ 2000 in the equation (2), a stable drying and solidification behavior cannot be obtained, and yarn breakage occurs.

Hereinafter, the present invention will be described with reference to examples and comparative examples. Evaluation of the fibers obtained in Examples and Comparative Examples was performed by the following method.
(Dyeing and absorbance measurement)
The cellulose acetate fiber of the present invention is used as a knitted fabric and dyed under the following conditions. Absorbance [ABS 580 nm] is 0.5 ml of a knitted fabric after dyeing in a methylene chloride / methanol mixed solution (mass mixing ratio 91/9) 500 ml. And the absorbance at a wavelength of 580 nm. It is believed that the greater the absorbance, the greater the amount of dye incorporated into the fiber.
・ Scouring Refining Agent: Score Roll 900 (manufactured by Kao Co., Ltd.) 0.2 mass% aqueous solution Bath ratio: 1: 100, 80 ° C. × 30 min. Dyeing Dye: Dianix Black TAN (manufactured by Mitsubishi Kasei Hoechst) 6 mass% Amount against fiber Dyeing aid: DISPER TL (manufactured by Meisei Chemical Co., Ltd.) 0.5 g / liter
URTRA MT-N2 (manufactured by Daiwa Chemical Co., Ltd.) 0.5 g / liter Bath ratio: 1:30, Boil x 60 minutes, reducing cleaning Hydrosulfite (manufactured by Kanto Chemical Co., Ltd.) 1 g / liter anhydrous sodium carbonate (Kanto) Chemical Co., Ltd.) 1 g / liter Meisanol BHS NEW (manufactured by Meisei Chemical Co., Ltd.) 2 g / liter 60 ° C. × 15 minutes

(Observation of three-layer composite form)
The cellulose acetate fiber of the present invention is alkali-treated under the conditions shown below, and only the diacetate component is celluloseized to give a difference in light transmittance with the triacetate component. That is, the cross-sectional shape occupied by the diacetate component and the state of exposure to the fiber surface are observed.
・ Alkaline treatment liquid: Sodium hydroxide 1 mass% aqueous solution ・ Treatment liquid bath ratio: 1: 100
・ Processing temperature: 60 ℃
Processing time: 10 minutes (Example 1)

As an outer layer component, cellulose triacetate in which 97% of hydroxyl groups are acetated is dissolved in a mixed solvent of methylene chloride / methanol (mass mixing ratio 91/9), and a spinning dope a having a solid content concentration of 22.0% by mass is obtained. Prepared. In addition, cellulose diacetate in which 80.3% of the hydroxyl groups are aceticated as an intermediate layer component is dissolved in a mixed solvent of methylene chloride / methanol (mass mixing ratio 88/12), and the solid content concentration is 22.1% by mass. A spinning stock solution b was prepared.
Using the two types of spinning dope, the ratio of the intermediate layer to 20 volume% in the composite spinning nozzle having a circular nozzle hole shape, a nozzle hole diameter of 0.026 mm, and 20 nozzle holes, and the intermediate layer is Cellulose diacetate, arranged so that the outer layer is cellulose triacetate, dry composite spinning at a spinning speed of 600 m / min, Vf / Vj = 0.30, Vj = 1700 m / min, and an intermediate layer of 84 dtex / 20 filament A cellulose acetate composite fiber of cellulose diacetate and a trilayer bonded type cellulose acetate composite fiber in which both outer layers are cellulose triacetate was obtained.
There are few folds peculiar to acetate fibers on the fiber surface, and there are fine folds on the fiber surface in a direction substantially perpendicular to the fiber axis. A portion of diacetate is present on the fiber cross section after alkali treatment. It was exposed to.
The composite fiber was dyed with boiling black dye with boiling water, and the dye adsorption rate was measured. As a result, the absorbance at 580 nm = ABS 580 nm was 0.2427, which was 16.2 in comparison with Comparative Example 1 described below consisting of 100% triacetate. % Bigger result.
The dyeing density of the knitted fabric obtained by spinning the acetate composite spun fiber by the above method on a scale of 6 spindles and dyeing each in the same dyeing bath was very small in dispersion and excellent in uniformity. Further, this knitted fabric was superior in visual gloss compared to the knitted fabric of Comparative Example 1 described below, and had an elegant gloss unique to acetate fibers.
(Comparative Example 1)

Using the cellulose triacetate spinning stock solution a in which 97% of the hydroxyl groups prepared as the outer layer component of Example 1 are acetic acid, 100% cellulose triacetate fiber is the same as in Example 1 using the same nozzle as in Example 1. Dry spinning was performed under the conditions to obtain 84 dtex / 20 filament cellulose triacetate fibers.
The fiber surface had deep folds peculiar to acetate fibers, non-uniform folds of ridges were generated, and the fiber surface had minute folds in a direction substantially perpendicular to the fiber axis. Further, this fiber was dyed with boiling black dye with boiling water, and the dye adsorption rate was measured. As a result, the absorbance at 580 nm = ABS 580 nm was 0.2089.
The dyeing density of the knitted fabric obtained by spinning the triacetate fiber according to this example on the scale of 6 spindles and dyeing each in the same dyeing bath has very large variation and there is a problem in uniformity. The glossiness was suppressed, and the elegant glossiness unique to acetate fibers was insufficient.
(Comparative Example 2)

In Example 1, except that the proportion of the intermediate layer was 15%, dry composite spinning was performed under the same conditions as in Example 1, and an intermediate layer of 84 dtex / 20 filaments was cellulose diacetate, and both outer layers were cellulose triacetate. A cellulose acetate composite fiber of the type was obtained. There are few folds peculiar to acetate fibers on the fiber surface, and there are minute folds on the fiber surface in a direction substantially perpendicular to the fiber axis. In the cross-sectional shape after alkali treatment, a part of diacetate is on the fiber surface. It was exposed.
The composite fiber was dyed with boiling black dye with boiling water, and the dye adsorption rate was measured. As a result, the absorbance at 580 nm = ABS 580 nm was 0.2341, and the result was 12.0% larger than Comparative Example 1 consisting of 100% triacetate. Met.
This knitted fabric was superior in appearance to the knitted fabric of Comparative Example 1, and had an elegant gloss characteristic unique to acetate fibers. However, the dyeing density of the knitted fabric obtained by spinning the acetate composite spun fiber by this method on the scale of 6 spindles and dyeing each in the same dyeing bath has a little variation, and there is a problem in uniformity.
(Comparative Example 3)

Compared to Example 1, dry compound spinning was performed at a spinning speed of 600 m / min using a compound spinning nozzle having a circular nozzle hole shape, a nozzle hole diameter of 0.038 mm, and a nozzle hole number of 20, and Vf / Vj = 0.75, Vj. A dry composite spinning was performed under the same conditions as in Example 1 except that the rate was 800 m / min, to obtain a cellulose acetate composite fiber having a three-layer joining type in which 84 dtex / 20 filament intermediate layer was cellulose diacetate and both outer layers were cellulose triacetate. It was. There were few creases peculiar to acetate fibers on the fiber surface, and there were no fine creases on the fiber surface in a direction substantially perpendicular to the fiber axis of the fiber of Example 1.
This knitted fabric was superior in appearance to the knitted fabric of Comparative Example 1, and had an elegant gloss characteristic unique to acetate fibers. However, the dry touch feeling peculiar to acetate was not obtained.

It is a perspective view which shows the composite spinning fiber by this invention in a partial cross section.

Explanation of symbols

1 Triacetate component 2 Diacetate component 3 Minute crease on fiber surface

Claims (3)

  The fiber cross-section is a composite spun fiber consisting of a three-layer joined structure in which diacetate is sandwiched between triacetates, and at least part of the diacetate is exposed on an arbitrary surface of the fiber made of triacetate, An acetate composite spun fiber having fine folds in a substantially perpendicular direction and having a dye adsorption rate of 15% or more at the time of boiling water dyeing compared to a fiber composed of 100% triacetate. A method for producing an acetate composite spun fiber, comprising dry spinning a composite spinning solution that forms a three-layer joining structure in which diacetate is sandwiched between triacetates under conditions satisfying the following formulas (1) and (2).
(1) 0.15 <Vf / Vj <0.60
(2) 1000 <Vj <2000
(Where Vf is the take-up speed of the spun yarn (m / min), Vj is the discharge linear speed (m / min) from the spinning nozzle of the spinning stock solution, and Vj is (the amount of spinning stock discharged / the spinneret (Total pore area))   A woven or knitted fabric comprising the acetate composite spun fiber according to claim 1.