JPH11158747A - Cloth for industrial material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain cloth for industrial materials having tenacity and stretch recovery both required for industrial cloth, and also excellent in resistance to light and heat or the like. SOLUTION: This cloth is prepared by weavying a polyester fiber, which has propylene terephthalate monomer units as principal repeating units and has an intrinsic viscosity of >=0.7, the breaking strength of >=6g/d and the breaking elongation of >=12%, into at least part of the cloth. The cloth is woven so as to have covering factors K (expressed by the following formula) of >=440 both in the warp and weft directions: K=[(a grade of denier)<1/2> ×(number of yarns per inch)].

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a fabric having excellent stretch recoverability, and relates to a construction net, a tent,
The present invention relates to a fabric having excellent mechanical strength and high dimensional stability required for industrial applications such as reinforcing materials for various membrane materials, seat materials for office and vehicle chairs, and the like.

[0002]

2. Description of the Related Art In recent years, fishery applications such as fishing nets and nets,
Many fabrics are used for industrial purposes such as construction nets, tents, various membrane reinforcing materials, office and vehicle chairs and bed cushions. These fabrics are used in fields where high stress is repeatedly applied, and fabrics having high strength and excellent dimensional stability are required. Hitherto, polyethylene terephthalate, nylon 6, or nylon 6, 6, etc., have been used in fields requiring high strength. Although these fibers were strong, they were unsatisfactory in terms of dimensional stability, especially stretch recovery.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention, in view of the prior art, to provide a fabric having both high strength and dimensional stability. In particular, it is an object of the present invention to provide a fabric having good elongation recovery properties in industrial material fabrics often used repeatedly under high stress.

[0004]

That is, the present invention provides a propylene terephthalate having an intrinsic viscosity of 0.7 or more as a main repeating unit and a breaking strength of 6 g / d or more and a breaking elongation of 12 or more.
% Or more of polyester fibers used for at least a part of the fabric, and the cover factor K in each of the weft directions is 440.
An industrial material fabric as described above.

[0005] The intrinsic viscosity of the polymer used in the present invention must be 0.7 or more. When the intrinsic viscosity is less than 0.7, the strength required for fibers for industrial materials cannot be obtained. A more preferred intrinsic viscosity is 0.8 or more.

Some of the constituent fibers must be polyester fibers containing propylene terephthalate as a main repeating unit.

More specifically, the polyester in the present invention is directed to a polyester containing terephthalic acid as a main acid component and trimethylene glycol as a main glycol component. Further, a polyester in which part of the terephthalic acid component is replaced by another difunctional carboxylic acid component may be used, and / or part of the glycol component is replaced by the above-mentioned glycol or other diol component other than the main component. It may be polyester. Examples of the bifunctional carboxylic acid other than terephthalic acid used herein include, for example, isophthalic acid, naphthalenedicarboxylic acid, diphenyldicarboxylic acid, diphenoxyethanedicarboxylic acid, β-hydroxyethoxybenzoic acid, p-oxybenzoic acid, adipic acid And aromatic, aliphatic and alicyclic bifunctional carboxylic acids such as, sebacic acid and 1,4-cyclohexanedicarboxylic acid. Further, as the diol component other than the above glycol, for example, ethylene glycol, tetramethylene glycol, cyclohexane-
Aliphatic, alicyclic, such as 1,4-dimethanol, neopentyl glycol bisphenol A, bisphenol S,
Examples thereof include aromatic diol compounds and polyoxyalkylene glycols. Further, as long as the polyester is substantially linear, a polycarboxylic acid such as trimellitic acid and pyromellitic acid, a polyol such as glycerin, trimethylolpropane, and pentaerythritol, 5-hydroxyisophthalic acid, and 3,5-dihydroxybenzoate Monomers having three or more functional ester-forming groups, such as acids, can be used. Further, a blend of the above-mentioned polymer or copolymer may be used.

In the present invention, the polyester fiber composed of the above-mentioned dicarboxylic acid component and diol component is satisfactory in flex fatigue properties, elongation recovery properties and dyeing properties unless the propylene terephthalate component is at least 50% of the whole. No material is available. It is particularly preferred that 80 mol% or more of the repeating units are propylene terephthalate units.

Further, small amounts of other optional polymers, antioxidants, antistatic agents, dye improvers, dyes, pigments, matting agents, optical brighteners, inert fine particles and other additives may be added to the polyester in small amounts. An agent may be contained. In particular, when adding inert fine particles, any of the external precipitation method and the internal precipitation method can be adopted.

The breaking strength and elongation of the fibers constituting at least a part of the fabric of the present invention must be at least 6 g / d and at least 12%, respectively. Breaking strength is 6
If it is less than g / d, the number of components required to obtain a predetermined fabric strength increases, and the fabric weight and thickness increase, which is not preferable. The preferred breaking strength is 7 g / d, and the more preferred breaking strength is 8 g / d or more. Further, when the elongation at break of the fiber is less than 12%, since the elongation is small even if the strength is high, the breakage due to stress concentration is apt to occur and the breaking strength and impact resistance are poor, which is not preferable as a fabric for industrial materials.
The preferred elongation at break is 15% or more.

[0011] The cover factor K of the fabric according to the present invention must be 440 or more in both the longitudinal directions. K
When the value is less than 440, the strength required for the industrial material fabric is not satisfied, which is not preferable. A more preferred K value is 500 or more.

It is preferable that the K value of the present fabric be the same value in both the longitudinal direction and the better balance in mechanical properties of the fabric, but it is not limited thereto.

The filament to be formed preferably has a denier of 100 denier or more. In this case, the filament may be a multifilament or a monofilament. The larger the single yarn denier,
It is preferable because durability such as heat resistance and light resistance is improved. Preferred single yarn denier is 3 denier or more. If the constituent filaments are less than 100 denier, it is necessary to increase the number of driving filaments in order to obtain the strength required for industrial materials, which is not preferable because the weaving process becomes complicated. The constituent denier may be large, but if it is too large, problems such as thickening of the cloth and coarseness occur. It is preferably at most 5,000 denier, more preferably at most 3,000 denier.

In order to obtain an industrial fabric having an excellent stretch recovery property, which is the intended object of the present invention, it is more preferable that the PPT fiber is used in an amount of 40% or more in each of the weft directions of the fabric. Become. More preferably, it is 60% or more. When the PPT fiber is used in both the weft directions, it is preferable to use the same amount in the weft direction in terms of the balance of the fabric, but the present invention is not limited to this.

When PPT fibers are used in combination with other fibers, the yarn properties such as heat shrinkage and elongation at break of the yarn, and the yarn composition such as the constituent fineness and single yarn denier have the same value. Are preferred. This is necessary in order to make the cloth surface even and to improve the strength utilization rate in the cloth. The difference in each property is 5% or less, more preferably 3% or less, the elongation at break is 10% or less, more preferably 5% or less in dry heat shrinkage (150 ° C. × 30 minutes). Within denier, more preferably within 400 denier, the single yarn denier difference is within 5 denier.

The fabric according to the present invention is most preferably plain weave, but the present invention is not limited to this, and PPT fibers may be used for other woven fabrics such as twill and satin, or a part of knitted fabric.

As described above, the fabric for industrial materials into which the polyester fiber of the present invention is driven so as to have a certain cover factor has excellent stretch recovery properties and is required for industrial material applications such as high strength. It is possible to satisfy various physical properties. In particular, by setting the single yarn denier of the fiber to be used to 5 denier or more, the durability such as light resistance and heat resistance is improved, so that a more preferable industrial fabric can be obtained.

[0018]

The present invention will be described in more detail with reference to the following examples. The physical properties and evaluations in the examples were obtained as follows.

Yarn strength and elongation: Measured according to the method described in JIS L 1013. In addition, 300mm of pulling speed
/ Min, and a gripping distance of 250 mm.

Fabric strong elongation; JIS L 1096 1
The measurement was performed according to the method described in 2.1 (Method A). In addition, it measured by the labeling strip method with the width of a test piece of 50 mm, and a grip interval of 200 mm and a pulling speed of 100 mm / min. Preferred strength is 200 kg / 5 cm or more.

Stretch recovery rate: JIS L 1096 6.
Performed by a method according to 14.2 (Method C). However, the extension rate was set to 20% of the grip interval. Preferred stretch recovery is 8
5% or more.

(Examples 1 to 3, Comparative Example 1)
0.1 m of polypropylene terephthalate resin of 70
After predrying at 80 ° C. for 4 hours under a vacuum of mHG, solid phase polymerization was performed at 180 ° C. for 20 hours under the same vacuum conditions to obtain a PPT resin having an intrinsic viscosity of 0.995. After the solid-phase polymerization, the vacuum was broken with nitrogen gas, and the container was transferred to a container without touching the outside air. The obtained PPT resin was melted by a screw-type extruder adjusted to 280 ° C., and then spun at the same spinning temperature of 280 ° C., cooled at 20 ° C. with a cooling air of 0.3 m / s, and cooled at 500 m / min. At the spinning speed, and once wound up. The undrawn yarn was preheated with a hot roller adjusted to 60 ° C, stretched 5.8 times under steam at 120 ° C, and heat-set with a hot roll set at 140 ° C at a relaxation rate of 3%. The resulting drawn yarn had a total denier of 1,000 denier, a single yarn denier of 5.2 denier, a breaking strength of 8.1 g / d and a breaking elongation of 1.
9%. Using 100% of the drawn yarn in the weft direction,
Various plain weave fabrics having K values in the range of 411 to 948 were produced. Table 1 shows the properties of the obtained fabric.

[0023]

[Table 1]

From these results, it was clarified that a fabric having a low K value was insufficient in strength and sometimes caused misregistration, and thus was not a preferred fabric as a fabric for industrial materials.

Comparative Example 2 A yarn (hereinafter referred to as PET fiber) using polyethylene terephthalate resin (intrinsic viscosity 0.993) obtained by the same method as the conditions described in Example 1 was used.
Weaving was performed under the same conditions as in Example 1. First, total denier of the obtained drawn yarn was 1000 denier, and single yarn denier was obtained.
Was 5.3 denier, the breaking strength was 8.6 g / d, and the breaking elongation was 16%. Next, the properties of the obtained fabric are shown in Table 2. Although the strength and the like of the constituent fibers are preferable, the obtained fabric is not preferable as a fabric for industrial materials because the stretch recovery rate is insufficient.

[0026]

[Table 2]

(Examples 4 to 6) The ratio of PPT fiber and PET fiber in both directions is 3: 1 (Example 4), 1: 1 ratio (Example 5) and 1: 3 ratio (implementation). In Example 5), a woven fabric was prepared. Table 3 shows the results.

[0028]

[Table 3]

As a result, it was clarified that the woven fabric having a ratio of PPT fiber to PET fiber of 25:75 had a slightly insufficient elongation recovery rate, and was not sufficient as a fabric for industrial materials.

[0030]

According to the present invention, it is possible to achieve both the strength required for industrial fabrics and the elongation recovery ratio, and to obtain industrial fabrics having excellent light resistance and heat resistance.

Claims (3)

[Claims] 1. A rupture strength of 6 g / cm3, wherein propylene terephthalate having an intrinsic viscosity of 0.7 or more is a main repeating unit.
An industrial material fabric comprising a polyester fiber having a breaking elongation of at least d and a breaking elongation of at least 12%, and having a cover factor K of 440 or more in each of the weft directions represented by the following formulas. K = (denier) ^1/2 x (weave density) [books / in] 2. The fabric for industrial materials according to claim 1, wherein the polyester fiber is a filament having a denier of 100 or more. 3. The industrial material fabric according to claim 1, wherein the polyester fiber is used in an amount of 40 wt% or more in each of the weft directions.