JPH08134722A - Splitting conjugate fiber - Google Patents

Abstract

PURPOSE: To obtain a splitting conjugate fiber with a specific thermoplastic water-absorbing resin as one component, readily splittable with water with the resultant ultra-fine or special modified cross section fiber representing a single component. CONSTITUTION: This conjugate fiber is made up of favorably fiber-forming thermoplastic resin component 1 and thermoplastic water-absorbing resin component 2 swellable and gellable with water and dispersible in water, having such structure that the component 1 is divided by the component 2. When this fiber is treated with water, the component 2 is swollen to effect splitting the component 1, and gelled and then dispersed in water and removed eventually. The water treatment of this fiber is normally conducted in the form of knitted fabric.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a splittable conjugate fiber which can be easily split by water.

[0002]

2. Description of the Related Art Conventionally, various splittable conjugate fibers have been proposed for the purpose of obtaining ultrafine or specially shaped cross-section yarns. For example, there is a composite fiber in which a poorly soluble alkali polymer component is divided by a readily soluble alkali polymer component. This composite fiber has a problem in safety and its treatment because a strong alkaline aqueous solution is used for division. Further, depending on the combination of polymers, there is a problem that not only the alkali-eluting component but also other components are eluted by the alkali.

Further, as a splittable conjugate fiber which can be split only by giving a mechanical impact in the presence of water without using an alkali, it is composed of polyesters having different melt viscosities and has a higher melt viscosity. There has been proposed a composite fiber using a material having a property of absorbing water and swelling, which is obtained by blending a polyalkylene glycol with the above (Japanese Patent Application Laid-Open No. 6-2221).
No.). This composite fiber needs to be combined with a specific polyester, is not versatile, and has a problem that the fiber obtained by dividing it is a bicomponent mixed fiber.

Further, there is a composite fiber in which incompatible components such as a polyester component and a polyamide component are combined. This composite fiber is separated at the interface between both components by mechanical impact and split, and the polymer component that can be used is limited, and the fiber obtained by splitting is also a mixed fiber of two components. There is a problem.

[0005]

The present invention is intended to provide a splittable conjugate fiber which can be easily split with water, and the fiber obtained by splitting is a single component fiber.

[0006]

Means for Solving the Problems As a result of intensive studies for solving the above problems, the present inventors achieved this object by using a specific thermoplastic water-absorbing resin as one component of splittable conjugate fiber. The present invention has been achieved and has reached the present invention.

That is, the gist of the present invention consists of a component A consisting of a thermoplastic resin having a good fiber-forming property and a component B consisting of a thermoplastic water-absorbing resin which swells and gels with water and can be dispersed in water. A is a splittable conjugate fiber in which A is split by component B.

The present invention will be described in detail below.

In the present invention, the thermoplastic resin as the component A may be any thermoplastic resin that gives fibers having practical physical properties. Specifically, polyethylene terephthalate, polybutylene terephthalate, and their copolymers may be used. Examples thereof include polyesters such as polymers, nylon 6, nylon 66 and polyamides such as copolymers thereof, and polyolefins such as polypropylene. In component A,
If necessary, additives such as matting agents, colorants, stabilizers, antistatic agents, flame retardants can be added.

As the thermoplastic water-absorbent resin of the component B, a resin which swells and gels with water, has a low strength, and can be dispersed in water is used. The water absorbent resin is
Those having a water absorption capacity of 2 times or more, preferably 10 times or more, of their own weight are preferable. A resin having a small water absorption capacity cannot obtain a sufficient expansion force necessary for division even when treated with water, and the strength of the gel produced is large, so that it cannot be dispersed and removed in water. As the thermoplastic water-absorbent resin that can be used in the present invention, there is a cross-linked product of polyethylene oxide, which is commercially available from Sumitomo Seika under the trade name of "Aqua Coke". As the component B, a thermoplastic water-absorbent resin mixed with a non-water-absorbent resin such as polyester or polyamide can also be used, and by blending these, the amount of the water-absorbent resin used can be reduced.

The composite form is not particularly limited as long as the component A is divided by the component B. For example,
Examples include the forms shown in FIGS. Figure 1
In 2, 1 indicates component A and 2 indicates component B.

The ratio of the component A to the component B is preferably such that the ratio of the component B is as small as possible in the range where smooth composite spinning is possible, but usually about 3/1 by weight is suitable.

The composite fiber of the present invention can be produced by melt spinning component A and component B by a conventional method and stretching.

When the conjugate fiber of the present invention is treated with water, the component B swells and the component A is divided, and the component B gels with water, and the strength of the gel produced is small.
It is dispersed in water and removed, and becomes an ultrafine or specially shaped fiber having the component A. Water treatment for dividing and removing the component B is usually performed in a woven or knitted state. For water treatment,
It is also preferable to employ a method in which heated water is used if necessary, and after treatment with steam, washing with water is carried out.

[0015]

EXAMPLES Next, the present invention will be specifically described with reference to examples. The measurement and evaluation methods in the examples are as follows. Water Absorption Capability A water absorbent resin was melted and discharged from a spinneret having 36 nozzles with a diameter of 0.3 mm and discharged, and a fibrous material obtained was used as a sample. This fibrous material was conditioned in an atmosphere of 20 ° C. and 65% RH for 24 hours, put a sample of weight W _{0 in} a polyethylene non-woven bag, soaked in tap water of 20 ° C. for 10 minutes, taken out, and sandwiched between qualitative filter papers After dehydration with, the weight W was measured, and the water absorption capacity and water absorption capacity Q (g / g) was calculated by the following formula (tea bag method). Q = (W-W ₀ ) / W ₀ Strength and Elongation Using Shimadzu Autograph DSS-500, 20 ° C, 65
The measurement was performed in a measurement room of% RH under the conditions of a sample length of 30 cm and a pulling speed of 30 cm / min. Dividability The composite drawn yarn was immersed in hot water for 10 minutes, washed in running water for 30 minutes, and then air-dried. The surface and cross section of the treated fiber were observed with an optical microscope and evaluated in the following three stages. ◯: Component B was completely eluted. (Triangle | delta): The component B partially remained and it partially divided. X: No division was observed.

Example 1 Relative viscosity as component A (96% sulfuric acid was used, concentration 1 g /
(6, dl, measured at a temperature of 25 ° C) 2.3 nylon 6 pellets, and as component B, Sumitomo Seika's "Aqua Coke" pellets with a water absorption capacity of 24.9 g / g were used, and the composites shown in Fig. 2 were prepared as follows. In the form, composite fibers with a composite weight ratio of 3/1 were produced. The above pellets were melted by using two extruders, spun at 250 ° C. from a spinneret having 36 spinning holes with a diameter of 0.3 mm, wound at a speed of 800 m / min, and then stretched 3 times. A composite drawn yarn of about 120d / 36f was obtained. Table 1 shows the yarn quality performance and splittability evaluation results of the obtained drawn yarn.

Example 2 As Component A, polyethylene terephthalate having a relative viscosity (measured at a concentration of 0.5 g / dl and a temperature of 20 ° C. of an equal weight mixture of phenol and tetrachloroethane as a solvent) of 1.4 was used, and the spinning temperature was 285. A composite drawn yarn was obtained in the same manner as in Example 1 except that the temperature was changed to 0 ° C. Table 1 shows the yarn quality performance and splittability evaluation results of the obtained drawn yarn.

Examples 3 to 6 As Component B, a mixture in which "Aqua coke" as in Example 1 and nylon 6 having a relative viscosity of 2.3 were mixed at the ratio shown in Table 1, and the spinning temperature was 245 ° C. A composite drawn yarn was obtained in the same manner as in Example 1 except for the above. Table 1 shows the yarn quality performance and splittability evaluation results of the obtained drawn yarn.

Comparative Examples 1 and 2 As Component B, a mixture in which the same "Aqua coke" as in Example 1 and Nylon 6 having a relative viscosity of 2.3 were mixed at the ratio shown in Table 1, and the spinning temperature was 245 ° C. A composite drawn yarn was obtained in the same manner as in Example 1 except for the above. Table 1 shows the yarn quality performance and splittability evaluation results of the obtained drawn yarn.

[0020]

[Table 1]

[0021]

Industrial Applicability According to the present invention, there is provided a splittable conjugate fiber which can be easily split with water, and the fiber obtained by splitting is a fiber having a single component.

[Brief description of drawings]

FIG. 1 is a fiber cross-sectional view showing an example of a splittable conjugate fiber of the present invention.

FIG. 2 is a fiber cross-sectional view showing another example of the splittable conjugate fiber of the present invention.

[Explanation of symbols]

 1 component A 2 component B

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Akira Yamamoto 23 Uji Kozakura, Uji City, Kyoto Prefecture Unitika Ltd. Central Research Laboratory

Claims (1)

[Claims] 1. A component A composed of a thermoplastic resin having a good fiber-forming property and a component B composed of a thermoplastic water-absorbing resin which is swollen and gelled by water and dispersible in water, and the component A is divided by the component B. A splittable conjugate fiber characterized in that