JPH03220316A - Conjugate fiber - Google Patents

Abstract

PURPOSE:To obtain the conjugate fibers having mechanical crimps, not elongat ing unnecessarily by themselves, having excellent shape stability, card passing properties, spinnability and knitting and weaving processing properties, by using a polyester-based elastomer as a sheath component and a nonelastic polyes ter as a core component. CONSTITUTION:(A) 5-60wt.% polyester-based elastomer (e.g. block copolymer comprising polybutylene terephthalate as hard segment and polytetramethylene glycol as soft segment) is used as a sheath component and (B) a nonelastic polyester (e.g. polyethylene terephthalate) as a core component to give concentric sheath-core conjugate yarn, which is mechanically crimped at 8-16 peaks/inch number of crimps and 8-20% crimp index by press crimping to give the objective conjugate fibers.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention relates to a core-sheath composite fiber in which the sheath component is a polyester elastomer and the core component is an inelastic polyester.

[Prior Art] Polyester elastomers have been attracting attention for their use as high-elastic fibers due to their excellent rubber-like elastic properties, and various companies are proceeding with their development. For example, Tokuko Sho 53-1018
No. 2 discloses a method for producing a highly elastic blended yarn, and a fabric with high stretchability is obtained.

This polyester elastomer also has excellent properties such as a moist feel due to its high elasticity, mild luster, and high color development. It has a calm texture with a sense of luxury that I couldn't resist.

However, when this polyester-based elastomer fiber is mechanically crimped to form short fibers into spun yarn, the fibers themselves tend to stretch and have poor shape retention when mechanically crimped, resulting in poor card passability and spinnability. Furthermore, due to its poor thermal stability, it tends to shrink to a large extent during setting, and the fiber itself tends to stretch, resulting in a fabric with poor shape stability.

Japanese Patent Publication No. 60-1404 discloses a technology in which a polyester elastomer and polybutylene terephthalate are combined into a side-by-side type or an eccentric core-sheath type. Although this technique aims to achieve high stretchability, the spiral crimped form makes opening the fibers difficult and results in poor card passing properties and spinnability.

[Problems to be Solved by the Invention] As mentioned above, the problems of the present invention are to solve the problems with conventional high modulus fibers made of polyester elastomer,
To provide a polyester high-elastic fiber that has good card passability and spinnability, has the moist feel, mild luster, and high coloring property of a polyester elastomer, and can be made into a fabric with good shape stability. be.

[Means for Solving the Problems] The above-mentioned problems of the present invention are such that the sheath component is a polyester elastomer, the core component is an inelastic polyester, is substantially a concentric core-sheath composite fiber, and has mechanical crimping. This problem can be solved by using composite fibers.

Preferably, in the above-mentioned fibers, the problem can be solved by using composite fibers in which the sheath component is a block copolymer having polybutylene terephthalate as a hard segment and polytetramethylene glycol as a soft segment.

Hereinafter, the composite fiber of the present invention will be explained in more detail.

The polyester elastomer used in the present invention is a polyether ester block copolymer obtained by copolymerizing thermoplastic polyester as a hard segment and poly(alkylene oxide) glycol as a soft segment. That is, aromas such as terephthalic acid, isophthalic acid, phthalic acid, naphthalene-2,6-dicarboxylic acid, diphenyl-4-4' dicarboxylic acid, diphenikiethanecarboxylic acid, sodium 3-sulfoisophthalate, etc. are used as hard segments. group dicarboxylic acids, alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, aliphatic dicarboxylic acids such as succinic acid, oxalic acid, adipic acid, sebacic acid, dodecanedioic acid, dimer acid, or ester-forming derivatives thereof at least one dicarboxylic acid selected from l.

Aliphatic diols such as 4-butanediol, ethylene glycol, trimethylene glycol, pentamethylene glycol, hexamethylene glycol, neopentyl glycol, decamethylene glycol, 1,1-cyclohexane methanol, 1,4-cyclohexane dimetatool, tri- A polyester consisting of at least one diol component selected from alicyclic diols such as cyclodecane dimetatool or their ester-forming derivatives is used, while the soft segment has an average molecular weight of 40.
0-5000 polyethylene glycol, poly(1゜2
and polyester elastomers using at least one type of poly(alkylene oxide) glycol (7) such as 1.3-propylene oxide) glycol, poly(tetramethylene oxide) glycol, and a copolymer of ethylene oxide and propylene oxide. .

More specifically, examples include polybutylene terephthalate/polytetramethylene glycol copolymer, polybutylene terephthalate/polybutylene isophthalate/polytetramethylene glycol copolymer, and polyethylene terephthalate/polyethylene glycol copolymer. Among these, a particularly preferred polyester elastomer is a block copolymer having polybutylene terephthalate as a hard segment and polytetramethylene glycol as a soft segment, a so-called polybutylene terephthalate/polytetramethylene glycol copolymer.

For example, these polyester elastomers are
No. 55-120626 "Method for producing thermoplastic polyester copolymer elastomer" and Japanese Patent Publication No. 54-1
It can be obtained by conventionally known manufacturing methods such as ``Method for Manufacturing Composite Products'' published in Japanese Patent No. 9027.

The ratio of soft segment to hard segment in these polyester elastomers is 80/20 to 5/9.
A range of 5 (weight ratio) is preferable and appropriate. The polyester elastomer used in the fiber of the present invention preferably has a bending rigidity of 5.000 kg/al or less,
2,000 kg/a (the following are more preferable).

The inelastic polyester used in the present invention may be any polyester having a higher elastic modulus than the polyester elastomer, but preferably polyethylene terephthalate or polybutylene terephthalate. Since these have good interfacial affinity with the polyester elastomer, the adhesion between the core and sheath layers is good.

In addition, the polyester elastomer and non-elastic polyester used in the present invention may contain various additives, such as heat resistant agents, weather resistant agents, etc., in order to improve their properties as practical fibers.
Flame retardants, antioxidants, pigments, fillers, antistatic agents, etc. may be included. In this case, the additive may be localized in either the polyester elastomer or the non-elastic polyester, or may be distributed in any ratio between the two.

The above-mentioned polyester elastomer and non-elastic polyester are made into fibers by conventionally known concentric core-sheath composite spinning, and in this case, the ratio of the sheath component in the composite fiber is preferably 5 to 60 wj%, more preferably 15 to 3 Qvj%. . If the ratio of the sheath component is less than 5v+%, it will be difficult for the sheath component to cover the entire core component, and the sheath component will be more likely to be exposed on the fiber surface, resulting in problems such as staining spots.
The texture may also be rough and hard. Also 60w+%
If it exceeds 100%, the crimp set property will deteriorate and the degree of crimp will decrease.
It may be difficult to obtain a good spun yarn.

Further, the composite fiber of the present invention needs to have mechanical crimp. High-order processability, specifically, moderate crimping is required in order to card and form a sliver. This is because fibers that tend to develop spiral crimp due to thermal or mechanical stimulation are unsuitable because the fibers tend to become excessively entangled with each other, resulting in neps. This mechanical crimp is preferably a buckled crimp such as push crimp or gear crimp, and the number of crimp is 8 to 16 crimps/1 nc.
h. The appropriate degree of crimp is 8 to 20%.

〔Example〕

The fiber measurement method used in this example is as follows.

(1) Fineness Measured by the method of JIS L-1015-7-5-IA.

(2) Number of crimp, degree of crimp Measured by the method of JIS L-1015-7-5-IA, IB.

Example 1 Polybutylene terephthalate/polytetramethylene glycol (molecular weight 1000) = 100 as sheath component polymer
/40 parts copolymerized polyester elastomer was prepared using polybutylene terephthalate as the core component polymer, the core/sheath component ratio was set to be 70/30 by weight, and the material was discharged at a spinning temperature of 250°C and drawn at 1200 m/min. Ta.

This undrawn yarn was stretched 2.5 times in a 70°C hot water bath,
Crimp was applied using a push type crimping device, followed by relaxation heat treatment and cutting. Table 1 shows the properties of the obtained composite fiber.

The raw cotton of this composite fiber was spun onto a card and spun into yarn without any difficulty. Furthermore, when this spun yarn was used to make a fabric with a weave structure of 3/3 twill and dyed with a disperse dye, a fabric with a mild luster and a moist feel could be obtained. Furthermore, the stretchability of the fabric itself was not so great and it had excellent shape stability.

Comparative Example 1 Single-component spinning was performed under the same conditions as in Example 1, except that only the polyester elastomer used in the sheath component in Example 1 was used as the polymer. Table 1 shows the properties of the obtained fibers.

When this fiber was carded, the fiber itself stretched easily and could not be made into a sliver that could be used for practical purposes. .

Comparative Example 2 Composite spinning was performed under the same conditions as in Example 1 except that the same polyester elastomer and polybutylene terephthalate as in Example 1 were used at a component ratio of 50,150 and a side-by-side type die was used. Further, the composite fibers shown in Table 1 were obtained by stretching, crimping, and relaxing heat treatment in the same manner as in Example 1. This composite fiber developed spiral crimp, and when carded, many neps were generated.

Examples 2 to 5 Composite spinning was carried out under almost the same conditions as in Example 1, except that the type and ratio of the polymers of the core component and sheath component were changed as shown in Table 2, and further drawing, crimping, and relaxation heat treatment were carried out. The fibers were obtained.

The obtained fibers could be spun without any particular problems, and the fabrics using them had good dyeability and morphological stability.

In addition, in the table, PBT is polybutylene terephthalate, P
TMG is an abbreviation for polytetramethylene glycol.

Example 6 The polymer conditions were as shown in Table 2, and the spinning temperature was 280°C.
The spinning, stretching, crimping, and relaxation heat treatment were carried out in substantially the same manner as in Example 1, except that the following steps were taken: Table 2 shows the properties of the obtained fibers and the obtained fabric.

Table 1 [Effects of the Invention] The composite fiber of the present invention does not expand or contract unnecessarily due to the inelastic polyester core component, and also has good shape stability during mechanical crimping, so it has excellent card passability, spinnability, and even knitting and weaving properties. Excellent workability.

By using the composite fiber of the present invention, it has a moist and warm feel due to the polyester elastomer on the fiber surface, mild luster, and high color development.
In addition, a fabric with good shape stability can be obtained.

Furthermore, since the polyester elastomer of the surface layer has a low melting point, this raw cotton can be used to obtain a heat-adhesive nonwoven fabric.

Claims (3)

[Claims] (1) A composite fiber characterized in that the sheath component is a polyester elastomer, the core component is an inelastic polyester, the fiber is substantially a concentric core-sheath composite fiber, and is mechanically crimped. (2) The polyester elastomer of the sheath component is a block copolymer with polybutylene terephthalate as a hard segment and polytetramethylene glycol as a soft segment, and the inelastic polyester of the core component is polyethylene terephthalate or polybutylene terephthalate. , the composite fiber according to claim (1). (3) The composite fiber according to claim (1) or (2), wherein the ratio of the sheath component is 5 to 60 wt%.