JPH09273050A - Cushioning knitted fabric - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a cushioning knitted fabric having a prescribed thickness, a prescribed thermal compression recovery and a multi-layered cross section, large in tensile elastic modulus, excellent in a cushioning property and dimensional stability, and useful as a base fabric for tapes, etc. SOLUTION: This cushioning knitted fabric has a thickness of >=0.8mm, a 50% thermal compression recovery of >=60%, and a three-layered structure cross-section comprising interlock circular knitted fabrics or interlock flat knitted fabrics. The knitted fabric preferably has a tenslle strength (tenslle elastic modulus) of >=0.3kg/cm in an elongation of 5% at least in one direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The knitted fabric of the present invention relates to a knitted fabric which has cushioning properties and has a small deformation when a tension is applied, such as a tape base cloth.

[0002]

2. Description of the Related Art Knitted fabrics having cushioning properties have already been manufactured in a large number such as double jersey, double russell, pile knitted fabric and moquette. However, a product having a thickness of 0.8 mm or more and an excellent heat compression recovery rate has not been manufactured. Moreover, a knitted fabric having cushioning properties, a large tensile elastic modulus against pulling, and a small dimensional deformation has not been manufactured.

The use of heat-fusible fibers in a knitted fabric to prevent fraying has already been described in JP-A-63-152444. This proposal is intended to prevent the run when the knitted fabric is broken by inserting the heat fusion yarn into the warp knitted fabric. Therefore, there is no description of the tensile elastic modulus and the dimensional stability against a large tensile force.

[0004]

An object of the present invention is to inexpensively supply a knitted fabric having excellent cushioning property, heat compression recovery rate and dimensional stability.

[0005]

The present inventors have completed the present invention as a result of improving the knitting machine and variously examining the structure of the knitted fabric. The cushioning knitted fabric of the present invention has a thickness of 0.8 m.
A knitted fabric having a three-layer structure having a cross section of m or more and a 50% heat compression recovery rate at 70 ° C. of 60% or more. 50% at 70 ℃
If the heat compression recovery rate is less than 60%, the settling will be too large to serve as a cushioning knitted fabric. 3
The layered knitted fabric can be manufactured by knitting a connecting yarn into a double-sided circular knitted fabric and a double-sided warp knitted fabric.

However, a knitted fabric having a simple three-layer structure has poor dimensional stability and poor heat compression recovery rate. As for the heating compression recovery rate here, the test knitted fabric is compressed by 50%, dried and heat treated at 70 ° C. for 24 hours, removed from the weight, and left for 2 hours. The thickness after the lapse of 2 hours after the weight was removed was divided by the initial thickness, and expressed by 100 times.

The knitted fabric has a three-layer structure including a front material, a connecting thread and a lining. The yarn of the outer material is not particularly limited. General filaments and spun yarns can be used. The material is also not particularly limited. Natural fibers, regenerated fibers, synthetic fibers, etc. can be selected depending on the application. It is preferable to use a heat-sealing fiber for the outer material because it helps prevent fraying of the outer material. In the case of filaments, it is preferable to use bulky textured yarn, for example false twist textured yarn, because it helps prevent fraying. Examples of filaments include polyethylene terephthalate, nylon, polypropylene and polyethylene.

When heat-fusible fibers are used for the outer material, the content is at least 10% by weight, preferably 15% by weight or more, more preferably 30% by weight or more. If the content of the heat-sealing fibers is small, the effect of preventing fraying is small.

The tethers play an important role in imparting cushioning properties to the knitted fabric. Therefore, bulky yarns such as false twisted yarns, different shrinkage mixed yarns, and heat fusion yarns may be used. When a heat-fusible yarn is used as the tie yarn, the content is at least 20% by weight or more, preferably 40% by weight or more, more preferably 70% by weight or more. When the content of the heat-sealing fibers is small, the heat compression recovery rate becomes small.

The heat-sealing fibers are already on the market, and the side-by-side type and the core-sheath type heat-sealing fibers are often used. These are fibers composed of polymers having different melting points, and the melting points differ depending on the type of polymer. 110, 13
There are heat fusion fibers having low melting point components of 0, 150, 170 and 200 ° C. Further, as the type of polymer, polyolefin as a low melting point polymer, copolyester,
Nylon and these modified products are often used.
Polypropylene, polyethylene terephthalate, polybutylene terephthalate, nylon 6, nylon 66, etc. are often used as the high melting point polymer. The denier of the heat-bonded single fiber is usually 2 denier, but the denier may be appropriately changed depending on the knitting property.

When fibers other than the heat-sealing fibers are made of a polymer similar to the sheath component (low-melting point polymer) of the heat-sealing fibers, the number of bonding points increases, so that the bonding effect increases. Typical synthetic fibers include, for example, polypropylene, polyethylene terephthalate, polybutylene terephthalate, nylon 6, nylon 66, etc., recycled fibers such as viscose rayon, acetate, etc., and natural fibers such as cotton, hemp, wool, silk, etc. It is recommended to select and use it appropriately according to the application.

The yarn used for the lining has two methods, a method A in which the same yarn as in the outer material is used and a method B in which 90% by weight or more of the heat-sealing fiber is used. By this method, it is possible to impart excellent tensile elastic modulus and dimensional stability to the knitted fabric.

In the case of method A, heat setting is performed with tension applied in one direction extremely during finishing of the knitted fabric.
By setting the tension and tension so that the residual elongation at break becomes 50% or less, excellent tensile elastic modulus and dimensional stability can be imparted to the knitted fabric, and the object is achieved. When using it for tape, etc., apply tension in the machine direction. In the case of Method B, sufficient tensile elastic modulus and dimensional stability can be imparted to the knitted fabric by performing sufficient heat treatment at the time of finishing the knitted fabric, and the object is achieved.

By appropriately selecting the above method, the knitted fabric of the present invention has a tensile strength (tensile elastic modulus) in at least one direction of 5% elongation of 0.3 kg / cm or more, which is preferable (good dimensional stability). .

The production of the knitted fabric can be achieved by using a general double-sided warp knitting machine or a double-sided circular knitting machine with an open space between shuttles. In the case of circular knitting, the knitting structure of the outer material and the lining material is preferably Tenjiku or Kashiko. In the case of warp knitting, general knitting may be used.

It is preferable that the connecting yarn is knitted without skipping stitches because the compression recovery rate can be improved. Also,
Regarding the thickness of the connecting yarn, it is preferable to use a yarn having a thickness of 70% or more of the thickness of at least one of the front material and the lining material because the compression recovery rate can be improved.

[0017]

The cushioning knitted fabric of the present invention has excellent cushioning properties and heat compression elastic modulus. Further, it has a large tensile elastic modulus and is excellent in dimensional stability against pulling. Furthermore, since it is a knit product, it is cheaper than woven fabric and economically superior.

[0018]

EXAMPLES The heat compression recovery rate in the examples is 5 at 70 ° C.
A 0% heating compression recovery rate is shown.

Example 1 A double-sided circular knitting machine, 28 gauge was used, and the knitting structure of the outer material and the inner material was interlocked, and the polyester filament SD75 / 36 and polyester false twisted yarn SD75 manufactured by Kanebo Co., Ltd. were used at 36 inlets. Alternately, / 36 was alternately supplied, and knitting was performed using polyester false twisted textured yarn SD75 / 36 manufactured by Kanebo Co., Ltd. The knitted circular knitted fabric was opened, stretched 180% in the machine direction, and heat-set at 180 ° C. for 2 minutes in a tensioned state to produce a cushioning knitted fabric of the present invention. The tensile elastic modulus in the machine direction of this knitted fabric was 0.5 kg / cm, the thickness was 1.63 mm, the heat compression recovery rate was 77%, and the tensile elongation at break in the machine direction was 40%.

Example 2 In the same manner as in Example 1, the yarn of the outer material was polyester false twisted yarn SD100 / 24 manufactured by Kanebo Co., Ltd., and the connecting yarn was the polyester false twisted yarn SD75 / 36 manufactured by Kanebo Ltd. Kanebo Co., Ltd. core-sheath type heat-sealing yarn LHC75 / 2
4 (low melting point 200 ° C.) and heat setting was performed at 180 ° C. for 2 minutes to produce the cushioning knitted fabric of the present invention. The tensile elastic modulus in the machine direction of this knitted fabric is 0.6
kg / cm, thickness 1.12 mm, heating compression recovery rate 8
The tensile breaking elongation in the machine direction was 4% and 152%.

Example 3 In the same manner as in Example 1, a double-sided warp knitting machine was used to fabricate outer yarn from polyester false twisted yarn SD75 / 36 manufactured by Kanebo Co., Ltd., and connecting yarn from polyester false twisted yarn SD10 manufactured by Kanebo Co., Ltd.
0/24, core-sheath type heat-sealing yarn L manufactured by Kanebo Co., Ltd.
Change to only HC75 / 24 (low melting point 200 ℃), 18
Heat setting was carried out at 0 ° C. for 2 minutes to produce the cushioning knitted fabric of the present invention. This knitted fabric had a tensile elastic modulus in the machine direction of 0.4 kg / cm, a thickness of 1.07 mm, a heat compression recovery rate of 83%, and a tensile elongation at break of 23 in the machine direction.
1%.

Comparative Example 1 A circular knitted fabric knitted in the same manner as in Example 1 was opened, stretched 100% in the machine direction, and the width was adjusted so that the thickness was almost the same as in Example 1, and tension was applied. 180
A cushioning knitted fabric was produced by performing heat setting at 2 ° C. for 2 minutes. The tensile elastic modulus in the machine direction of this knitted fabric is 0.
2 kg / cm, the thickness was 1.67 mm, the heat compression recovery rate was 53%, and the tensile elongation at break in the machine direction was 89%. Since this knitted fabric has a heat compression recovery rate of 53%,
The cushioning property was poor.

Claims (3)

[Claims] 1. A thickness of 0.8 mm or more and 5 at 70 ° C.
A knitted fabric with a three-layer structure having a 0% heat compression recovery rate of 60% or more. 2. The knitted fabric according to claim 1, wherein the three-layer structure is a double-sided circular knitted fabric or a double-sided warp knitted fabric. 3. The knitted fabric according to claim 1, wherein the tensile strength (tensile elastic modulus) in at least one direction when stretched by 5% is 0.3 kg / cm or more.