WO1991010761A1

WO1991010761A1 - Core/sheath composite fiber and process for their manufacture

Info

Publication number: WO1991010761A1
Application number: PCT/JP1990/000071
Authority: WO
Inventors: Shogo Mutagami; Taro Murata
Original assignee: Kanebo, Ltd.
Priority date: 1990-01-22
Filing date: 1990-01-22
Publication date: 1991-07-25

Abstract

The invention relates to a core/sheath composite fiber composed of a core component of a polyester having sulfon groups and a sheath component of polyphenylene sulfide and a process for manufacturing the same by multi-stage stretching. This fiber has an excellent adhesion between the core component and the sheath component, and hence no single yarn breakage takes place in the spinning or knitting step, thus providing good workability. Since its surface is covered with polyphenylene sulfide, it is exellent in heat resistance, fire retardance, and chemical resistance.

Description

Specification

Core-sheath type composite fiber and its manufacturing method

Technical field

The present invention relates to a core-type composite fiber composed of two types of fiber-forming polymers and having excellent wear resistance and heat resistance, and a method for producing the same.

Background technology

Conventionally, polyphenylene sulfide has high heat resistance and outstanding chemical resistance, and many attempts have been made to apply it not only to molded products but also to fibers and films. However, since the above-mentioned bolifenylene sulphide is expensive, there is a drawback that the use thereof increases the cost significantly. Therefore, it has been proposed to form a composite spin of, for example, Bolifen ylene sulfide and a general-purpose polymer component, for example, a polyester component (Japanese Patent Application Laid-Open No. 63-92724). There is a problem that the adhesiveness between the polyester and the polyester component is insufficient, causing separation in the weaving / feeding process and hindering the operation.

The present invention has been made in view of such circumstances, and has as its object to provide a core-shaped composite textile having excellent wear resistance, heat resistance, and chemical resistance, and a method for producing the same.

Disclosure of the invention

In order to achieve the above object, the present invention provides a cored conjugate fiber comprising a core component (A) and a 鞲 component (B), wherein the core component (A) is a polyester having a sulfone group. A first aspect of the present invention is a core-type composite fiber, wherein the component (B) is formed of polyphenylene sulfide, and a polyester having a sulfone group in an innermost part in a composite spinneret. And at the same time as supplying the melt of volifenylene sulfide to at least the peripheral portion of the above spinneret. A spinning step of spinning out both melts supplied from the spinneret, and a drawing step of drawing the spun yarn. In the drawing step, 96 or more The second point is the method of manufacturing a core-type composite fiber in which stretching at two or more sides is repeated by stretching temperature *

That is, the present invention provides an improvement in the adhesiveness between polyolefin sulfide (hereinafter abbreviated as rppsj) and polyester, which has been a problem in practical use of composite fibers of bolifenylene sulfide and polyester. A series of studies were repeated for the purpose. As a result, we were convinced that a special polyester having a sulfone group (hereinafter abbreviated as “sulfone-modified PET j”) had the best adhesion to PPS and was suitable as the polyester. However, since the sulfone-modified PET has a low melting point, if spun at a humidity higher than the ordinary spinning temperature of polyester, physical properties such as the strength of the obtained yarn will be reduced, which causes a problem of deterioration. On the other hand, if the spinning temperature of PPS (generally 300 ° C), the spinning temperature of ordinary polyester (generally 290 to 295) is 5 to 10 higher. Then, when the sulfone-modified PET was used as a core component and coated with PPS, it was found that the sulfone-modified PET, whose physical properties are easily degraded by heat, was protected by PPS and the composite yarn as a whole was less deteriorated, and the present invention was reached. Moreover, when producing the above-mentioned conjugated composite fiber, the PPS covering the textile surface is not sufficiently stretched by applying only one stretch as in the case of ordinary polyester. It was found that if the procedure was repeated in two or more gardens, both PPS and sulfone-modified PET could be stretched without impairing the physical properties of the polymer, and a composite-type composite fiber with excellent properties could be obtained.

Next, the present invention will be described in detail. As the sulfon-modified PET used as the core component (A) of the core-sheath type composite fiber of the present invention, for example, a polyester whose repeating unit is polyethylene terephthalate is copolymerized with 5-sodium sulfoisophthalic acid. And a blend of the above copolymer of polyethylene terephthalate and 5-sodium sulfoisophthalic acid with a homopolymer of polyethylene terephthalate. Among them, those composed of only a 5-sodium sulfoisophthalic acid copolymer are preferred. The above-mentioned 5-sodium sulfoisophthalic acid is used to introduce a sulfone group into the polyester, and its amount is 0.5 to 5 mol%, particularly 1 to 4.5 mol, based on the base poly (ethylene terephthalate). It is preferable to set to ΒΙΟ £%. If the amount is less than 0.5 * ο £%, the adhesion to the composite component (Β) described later will be poor, and the yarn component will be separated from the 鞲 component during the spinning, drawing, weaving and weaving processes, and the single yarn • yarn It tends to cause cutting and poor abrasion resistance. Conversely, if the content exceeds 5 mo, the strength of the core component (A) is reduced, which also tends to cause single yarn and yarn breakage.

The PPS used as the 铕 component (B) of the composite fiber of the present invention is a polymer in which at least 80 mo of the structural unit is "^] ~ S ~ r. As long as the amount does not exceed £%, other co-polymer components, polymers, additives, etc. may be included in the composite fiber of the present invention. The component (B) can be produced, for example, as follows: First, a melt of the sulfone-modified PET, which is the core component (A), is placed in a falling part in a spinneret for spinning a conjugate fiber. And at the same time, a melt of the PPS, which is the component (B), is supplied to at least the periphery of the spinneret. At this time, the spinneret temperature is 5 times lower than the normal polyester spinning temperature. It is preferable to set to about 295'C which is as high as ~ 10 W

. Then, the two supplied melts are spun from the spinneret to obtain an undrawn yarn. By subjecting the undrawn yarn to drawing at a drawing temperature of 96 ° C. or higher twice and repeatedly, the desired core-in-sheath type conjugate fiber can be obtained. When the stretching is repeated twice or more, it is preferable to lower the stretching ratio as the stretching is performed later, because the physical properties of the obtained fiber become better. As described above, stretching twice or more at a stretching temperature slightly higher than that of ordinary polyester (the stretching temperature of ordinary polyester is 85 to 95 * C) is achieved by sufficiently stretching the PPS to take advantage of its properties. This is taken into account. In the present invention, even if the stretching is performed at a high temperature of 96 • C 议, the sulfonated PET which is weak to heat and has conventionally had to be stretched at an overflow lower than a normal polyester stretching temperature is used. However, since the S2 is placed inside the PPS, thermal degradation does not occur even when the film is drawn at the above high drawing temperature.

The core-type composite fiber obtained in this way makes use of the heat resistance, confectionery resistance and flame retardancy of PP S, and furthermore, the core component, sulfon-modified PET, and the composite component, PP The adhesion of S is also good. The price can also be significantly lower than the PPS alone. Therefore, it can be widely used as a general clothing material and interior material. Also, Ru very useful der special applications requiring heat resistance, chemical resistance _β

In the present invention, the composite ratio of the core component (Α) and the II component (Β) is such that (Α) :( Β) is 1: 1 to 10: 1, particularly 2: 1 to 9: 1 on a volume basis. It is preferable to set to. In other words, when the composite ratio of the sheath component (Β) is smaller than 0.1 (A: B = l: 10), the resulting composite fiber has reduced abrasion resistance, and also has poor heat resistance and chemical resistance. There is a downward trend. Conversely, if it is larger than 0.5 (Α: Β = 1: 1), the cost increases and the operability deteriorates, resulting in low physical properties. It is easy to cause below.

Examples of the cross section of the core-type composite fiber of the present invention include various types as shown in FIG. 1> FIG. 2, FIG. 3, FIG. 4, FIG. 5, and FIG. . In these figures, A indicates the core component and B indicates the sheath component. The thickness of the thinnest portion formed by the composite component B is preferably set to 0.3 to 5 ttm, particularly 0.5 to 4.5 #m. If the thickness of the 耩 part is thinner than 0.3 #m, the abrasion resistance of the obtained yarn tends to deteriorate, and conversely, even if the thickness of the sheath part is thicker than 5 m, the effect of chemical resistance remains unchanged and costs Because it ’s only high.

Brief explanation of drawings

Figure 1, Figure 2, Figure 3, Figure 4, Figure 5 and Figure 6 is Ru illustration der showing an example of the cross-sectional shape of the core-sheath type composite fibers, respectively it present invention _β

BEST MODE FOR CARRYING OUT THE INVENTION

Next, examples will be described.

(Example 2, Comparative example)

Melt viscosity of 300 and 2500 Boys PPS is melted and extruded with 25 mm screw by 30 mm (TC) and 2.5mojg% of 5-sodium sulfoisophthalic acid is copolymerized by another 25 mm screw. The melted polyethylene terephthalate (hereinafter referred to as Γcopolymer PET) was melt extruded at 295 and both were guided to a spinneret of 295 · (to set the composite ratio of copolymer PET and PPS to 2: 1. The undrawn yarn was drawn under the conditions shown in Table 1 below so that the total draw ratio became 4.0. The cross-sectional shape was 75 dZ36 f as shown in Fig. 1. ^ w Stretching temperature ^ Stretching ratio Heat shrinkage (T (%) First stretching 100 3.0 2.02 1.6 47.6 Second stretching 100 1.5 2.77 17.0 36.8 Third stretching * 1 2 0.9 2.42 27.2 2.5 First stretching 100 ao 2.02 1.6 47.6 2® elongation 100 1.4 2.56 18.8 31.0

Two

No third extension

First stretch 100 3.0 2.02 41.6 47.6 Second stretch No

No third extension

* Relaxation and heat setting The above Examples 1 and 2 were able to be manufactured in a stable operation without spinning and yarn breakage during spinning and drawing. A sample obtained by tubular knitting of the drawn yarn was put on a Seafer-type abrasion tester (manufactured by Shimadzu Corporation), and rubbed 1,000 times using a load of 500 g and a friction cloth using a nylon tricot. Both of them had good friction resistance. On the other hand, in the case of the comparative example product in which multi-stage stretching was not performed, the stretching of the PPS was insufficient, and the 鞲 component was worn out during knitting, and the core component was exposed or cut off. *

(Examples 3 to 13)

Further, the single yarn weave, the composite ratio, and the 5-sodium sulfoisophthalic acid copolymerization ratio were changed as shown in Table 2 below, and various other composite fibers were obtained in the same manner as in the above Examples except for the other conditions. Then, a friction test was performed in the same manner. The results are shown in Table 2 below. Table 2

Claims

Scope of patent request

1. A cored composite fiber obtained by combining a core component (A) and a component (B), wherein the core component (A) is formed of a polyester having a sulfone group, and the sheath component (B) ) Is a core-sheath type composite fiber characterized in that it is formed of borifenylene sulfide.

2. A supply step of supplying a melt of polyester having a sulfone group to an inner portion in the spinneret and simultaneously supplying a melt of bolieulenylene sulfide to at least a peripheral portion in the spinneret; A spinning step of spinning the supplied melts from the spinneret, and a stretching step of stretching the yarn, wherein the stretching step is performed at a stretching temperature of 96 or more. A method of manufacturing a core-sheath type composite fiber, characterized in that it is performed by repeating two or more surfaces.