JP5551890B2 - Double layer fabric spring material - Google Patents

Description

  The present invention relates to a two-layered structure spring material suitable as a cushioning material for seat seats of automobiles, railway vehicles, aircraft, child seats, strollers, wheelchairs, furniture, offices and the like.

  Patent Document 1 below discloses a fabric spring material having a high tear strength and a high tear strength as a fabric spring material made of a three-dimensional knitted fabric. Such a cloth spring material uses a monofilament as a connecting thread in order to improve cushioning properties in the thickness direction. However, when a monofilament is used as the connecting yarn, the thickness of the fabric is thick, and there is a problem in handling properties such as transportation, storage, cutting and sewing of the fabric. In addition, since monofilaments are included in the connecting yarn, a run is generated from a hole formed by a flaw from a blade or a cigarette fire. Further, sink marks that are likely to occur on the front and back surfaces (a state where the monofilament is caught by a sharp object due to the jumping out of the monofilament, the monofilament slips out of the knitted fabric on the front and back surfaces, and the monofilament yarn is stretched and depressed) are not solved.

  In the following Patent Document 2, a knitted fabric composed of a front structure, a back structure, and a connecting yarn that connects the front and back structures, the yarn constituting the front structure and the connecting thread is a polyester multifilament yarn, and the back surface is configured. A hygroscopic three-dimensional knitted fabric, which is a hygroscopic synthetic fiber yarn, is disclosed. Such a three-dimensional knitted fabric is a knitted fabric used for general clothing and sports clothing, and is not sufficient as a double-layered knitted fabric with no consideration given to the breaking strength, tear strength, tension compression change, etc. of the fabric. It is a thing.

  Patent Document 3 below discloses a three-dimensional structure molded article in which a connecting yarn of a three-dimensional structure fabric formed by connecting front and back double-sided base fabrics is composed of a multifilament yarn and a monofilament fiber. This three-dimensional structure molded product is a three-dimensional structure fabric that becomes a base fabric for resin molding, and the purpose of the three-dimensional structure is to maintain the distance between the front and back surfaces of the resin molded product, No consideration is given to tear strength, tension change, and the like, and the performance of the two-layered structure spring material is not sufficient.

  When a monofilament is used for the connecting yarn that connects the two layers of the front and back, the monofilament that connects to the knitted fabric on the front or back surface slips, so that the stitches break and run occurs. In addition, since the monofilament of the connecting yarn has high rigidity, the monofilament jumps out of the knitted fabric on the front surface or the back surface, and the monofilament sink occurs during handling after the raw machine, resulting in poor surface quality of the knitted fabric.

WO2005 / 034684 JP 2004-3095 A JP-A-6-305064

  The problem to be solved by the present invention is to solve the above-mentioned problems of the prior art, and has a strong breaking strength and a high tearing strength, and is cut at a hole portion vacated by a scratch by a blade or a cigarette fire. This is a fabric spring fabric that does not easily cause a phenomenon (run) that can be continuously unwound in the knitting start direction by external force such as compression, and has a soft cushioning property in the thickness direction. An object of the present invention is to provide a two-layer structure cloth spring material excellent in fit with a human body.

  In order to achieve the above-mentioned problems, the present inventors have developed a yarn and fineness used for connecting two-layer structure knitted fabrics, warp and transverse breaking strengths and tear characteristics in a knitted fabric composed of a specific ground structure, and tension. As a result of intensive studies on the compression change, the present invention has been completed.

  That is, the present invention is as follows.

(1) A two-layer fabric spring material in which two layers of front and back knitted fabrics are connected by a connecting yarn that is false twisted with 100% multifilament yarn, and the finished fabric has a thickness of 2.0 to 5 A double-layer structure cloth spring material having a thickness of 0.0 mm, a breaking strength in the warp direction and a transverse direction of the knitted fabric of 600 N or more, and a tearing strength of 150 N or more.

  (2) Of the two layers of the front and back sides, one of the knitted fabrics is composed of at least two knit loop structures, one of which is composed of chain knitting or tricot knitting with two or less stitches, and the other The wrinkle is a two-layer structure cloth spring material according to (1), which is composed of a tricot knitting of 1 stitch or more and 8 stitches or less.

  (3) The two-layer structure cloth spring according to (1) or (2), wherein the warp yarn inserted in the warp direction is inserted in the same direction or different direction with respect to the other chain knitting or tricot knitting. Wood.

  (4) The double-layered structure spring material according to any one of (1) to (3), wherein the fineness of the multifilament yarn that connects the knitted fabrics of the two layers of the front and back is 50 dtex or more and 1000 dtex or less.

  (5) The two-layer structure cloth spring material according to any one of (1) to (4), wherein the multifilament yarn that connects the knitted fabrics of the two front and back layers is a bulky processed yarn.

(6) The knitted fabric of the two layers of the front and back is connected by a multifilament, and the cover factor of the knitted fabric formed by the connecting yarn of the multifilament and the surface yarn is 5 × 10 ⁴ or more and 5 × 10 The two-layer structure cloth spring material according to any one of (1) to (5), which is ⁵ or less.

  (7) The two-layer structure cloth spring material according to any one of (1) to (6), wherein the tension compression tear amount is within 20 mm.

  The two-layer structure cloth spring material of the present invention has a strong breaking strength and a high tearing strength, and the cut yarn starts to be knitted by an external force such as compression in a hole portion vacated by a scratch by a blade or a cigarette fire. It is a cloth spring material that does not easily cause a phenomenon (run) that can be continuously solved in the direction and has high safety, and has a soft cushioning property in the thickness direction and excellent fit with a human body.

  Hereinafter, the present invention will be specifically described.

  The two-layer structure cloth spring material according to the present invention forms a planar cushion material by stretching it to a frame of various shapes such as a substantially quadrangular shape and a polygonal shape by various methods such as sewing, resin molding, and bolting. In addition, the cushioning property when a person is seated is exhibited by the elongation characteristics of the two-layer structure cloth spring material. The cushion material may be formed of only the frame and the fabric for the cloth spring, but if necessary, a fibrous cushion material such as three-dimensional knitted fabric, hard cotton, non-woven fabric, urethane, skin material, etc. may be laminated on the cloth spring fabric. It may be a cushion material.

  The two-layer structure cloth spring material according to the present invention is configured by connecting two layers of front and back knitted fabrics with a multifilament yarn 100% connecting yarn. Multifilament yarns for connecting yarns include, but are not limited to, synthetic fibers such as polyethylene terephthalate fibers, polytrimethylene terephthalate fibers, polybutylene terephthalate fibers, polyester elastomer fibers, polyamide fibers, polyacrylic fibers, and polypropylene fibers. Not what you want. The form of the fiber may be any of unprocessed yarn, spun yarn, twisted yarn, false twisted yarn, fluid injection processed yarn, etc., but is preferably a bulky processed yarn subjected to false twisting, More preferred is a false twisted yarn obtained by subjecting polyethylene terephthalate fiber to a bulky process. A false twisted yarn is also preferable for improving soft cushioning properties. The fineness of the yarn used is preferably 50 to 1000 dtex, more preferably 80 to 600 dtex, still more preferably 100 to 350 dtex.

  The thickness of the finished fabric is 2.0 to 5.0 mm in order to obtain a soft cushioning property of the two-layer structure cloth spring material according to the present invention. From the viewpoint of improving transportability and cutting property, the thickness is preferably 2.0 to 3.0 mm. In the present specification, the “cutting property” means cutting property in consideration of the generation amount of scraps (such as cut pieces of cloth generated at the time of cutting) and the load applied to cutting.

  In the present invention, any one of the two-layer structure knitted fabric is composed of a ground structure composed of at least two knit loop structures, and the knit loop structure referred to here is a tricot knitted fabric. A knitting structure that always forms a knit loop. In order to improve the breaking strength and the tearing strength, at least one of the reeds constitutes a knit loop with a chain knitting or a tricot knitting of 1 stitch or more and 2 stitches or less. The other wrinkle is preferably a tricot knitting with a swing of 1 stitch or more and 8 stitches or less, so that the broken yarn can be prevented from being continuously unwound (run occurrence) in the knitting start direction.

  The swing width of the multi-needle swing is preferably 3 to 8 swings. If one side is swung by 3 stitches or more and the other is 9 stitches or more, the knitting property is inferior and the production becomes difficult, and the fabric stretches in the warp direction and the recoverability of the fabric is inferior. In addition to resistance to breaking and tearing, in addition to suppressing stitch deformation (texture deformation) and making a knitted fabric with good stretch recovery, at least one wrinkle of the ground texture should be chain knit or within 2 stitches It is necessary to form a knit loop with a tricot knitting. Further, when the insertion yarn is entangled with the ground structure of at least two sheets, sufficient resistance to breakage, tearing resistance and stretch recovery can be obtained.

  It is preferable that one chain knitting or tricot knitting is a front heel and the other tricot knitting is a back knitting, and one tricot knitting and the other tricot knitting are controlled in different directions to prevent over-extension and improve recovery of elongation. Is preferred. Further, in order to improve the performance for preventing the occurrence of run, the chain knitting or tricot knitting and the insertion yarn are preferably swung in the same direction, and more preferably swung in the opposite direction in order to suppress excessive elongation in the vertical direction.

  The two-layer structure cloth spring material according to the present invention has a strength capable of supporting a person's weight in a stretched state and capable of resisting sufficiently when an act of stroking a knee or an impact force such as a collision is applied. Is preferred. For this purpose, it is necessary that the breaking strength is 600 N or more and the tearing strength is 150 N or more. The breaking strength of the fabric for cloth springs according to the present invention is 600 N or more, preferably 1000 N or more, more preferably 1200 N or more. Moreover, the tearing strength of the two-layer structure cloth spring material according to the present invention is 150 N or more, preferably 200 N or more, more preferably 250 N or more.

  The fineness of the fibers constituting the structure of one surface of the two-layer structure knitted fabric according to the present invention is preferably 250 to 1300 dtex, more preferably 400 to 1300 dtex from the viewpoint of improving the breaking strength and the tearing strength. When the fineness of the fibers constituting the ground texture is less than 250 dtex, the breaking strength and tearing strength are inferior, and the deformation (texture deformation) of the stitches is large, and the stretchability is excessive and the recoverability is lowered. Further, when the ground structure is not composed of a knit loop structure having two or more sheets, the breaking strength and the tearing strength are lowered. On the contrary, if the fineness of the fibers constituting the ground structure exceeds 2000 dtex, the knitting property is inferior and the production becomes difficult.

The cover factor of the knitted fabric constituting the other side of the two-layer structure knitted fabric according to the present invention is preferably 5 × 10 ⁴ or more and 5 × 10 ⁵ or less, and the surface quality is improved, particularly the surface sink is improved. the, more preferably 10 ⁵ or more 3 × 10 ⁵ or less for. If the cover factor is within these ranges, the multifilaments of the connecting yarn are firmly pressed into the knitting structure of the knitted fabric, and the multifilaments of the connecting yarn are difficult to be pulled out by sharp objects, etc., and the quality and stability of the knitted fabric. Will also be good.

The cover factor is obtained by the following formula.
Cover factor = (total fineness of connecting yarn + total fineness of surface yarn) × course × well where total fineness is dtex, course and well are the number of loops per inch (pieces), and The unit is dtex / inch ² .

  In order to obtain a comfortable fit to the human body and a stable sitting comfort when the two-layer structure cloth spring material forms the seat and back of the seat, the two-layer structure cloth spring material is stretched. It is necessary to form a knitted structure with less deformation (texture deformation) of the stitches by stretching the seat frame in a tensioned state or a relaxed state. For this purpose, it is preferable to knit the insertion yarn in the vertical direction and / or the horizontal direction.

  When the insertion yarn is knitted in the vertical direction, it is inserted between the needle loop and sinker loop on the back surface knitted with a structure such as tricot knitting with a swing width of 3 stitches or less per course, or on the warp knitted fabric It is preferable to insert the insertion yarn in a straight line shape or in a zigzag state over the entire length of the three-dimensional knitted fabric while being inserted between the sinker loops of the ground yarn continuous in the length direction. When the insertion yarn is knitted in the horizontal direction, the insertion yarn is inserted in a state close to a straight line across the entire width of the warp knitted fabric between the needle loop and sinker loop of the ground yarn knitted with a structure such as tricot knitting. It is preferable to do.

  As for the method of knitting the insertion yarn, if it is inserted in the vertical direction, it can be inserted by the knitting structure, and at this time, in the underlap direction of the multi-needle swing tricot knitting of the ground structure to suppress the deformation (structure deformation) of the stitch. It is preferable to insert in a different direction. The swing width is preferably 3 stitches or less per course, more preferably 2 stitch swings or 1 swing swing than 3 swings. If the insertion is in the horizontal direction, the weft can be inserted using a Raschel knitting machine equipped with a weft insertion device.

  The fiber used in one of the two layers of the front and back surfaces of the two-layer structure fabric spring material or the insertion thread is polyethylene terephthalate fiber, polytrimethylene terephthalate fiber, polybutylene terephthalate fiber, polyester-based elastomer fiber, polyamide-based fiber Examples thereof include fibers, synthetic fibers such as polyacrylic fibers and polypropylene fibers, natural fibers such as cotton, hemp and wool, recycled fibers such as cupra rayon, viscose rayon and lyocell, and other arbitrary fibers. The cross-sectional shape of the fiber can be round, triangular, L-shaped, T-shaped, Y-shaped, W-shaped, Yaba-shaped, flattened, flat-shaped, dog-bone shaped, etc., multi-leafed, hollow or irregular Good. As the form of the fiber, any of unprocessed yarn, spun yarn, twisted yarn, false twisted yarn, fluid injection processed yarn and the like may be adopted. However, with respect to the yarn used in the ground texture, it is preferable to use a raw yarn (unprocessed yarn) from the viewpoint of tightening the stitch as much as possible to suppress the deformation of the stitch, and further from the point of tightening the stitch as much as possible during the finishing process. The dry heat shrinkage at 5 ° C is preferably 5 to 20%, and more preferably 7 to 16%.

  In order to set the breaking strength of the fabric for a fabric spring according to the present invention to 600 N or more and the tearing strength to 150 N or more, the strength is preferably 4 cN / dtex or more, more preferably 5 cN / dtex, still more preferably 6 cN / dtex or more. It is preferable that the warp knitted fabric is configured using at least a part of the ground structure on one side.

  In addition, for fibers used for insertion yarns in the vertical direction or the horizontal direction, polymethylene terephthalate fibers or polyetherester elastic yarns are used to improve stretch recovery and suppress plasticity after a person has been sitting for a long time. It is preferable to use elastic fibers such as. Furthermore, the insertion yarn is preferably a monofilament of 300 to 3000 dtex in order to provide surface rigidity for preventing a local drop when a person is sitting and obtaining a stable seating feeling. In addition, when a monofilament is used as an insertion thread, the monofilament may be bonded to the ground tissue in order to prevent the monofilament from slipping and causing tissue deformation or plastic deformation after sitting. The method of bonding is preferably a method in which a sheath core monofilament whose monofilament surface is covered with a low melting point polymer is used, and the knitted fabric is knitted and then heat-sealed by heat setting or the like.

  The two-layer structure cloth spring material according to the present invention is preferably used for a seat that is stretched on a frame to form a seat portion and / or a back portion, but the state in which the two-layer structure cloth spring material is stretched on the frame is limited. Instead, the two-layered structure spring material can be attached to the seat or back by stretching the circumference or at least two sides of the two-layered structure spring material in a tensioned or slackened state on the back or seat frame. What is necessary is just to form.

  Any method can be used as a method of fixing the two-layer structure cloth spring material to the frame. For example, as described in Japanese Patent Application Laid-Open No. 2002-219985, a plate member having a substantially U-shaped cross section and having a groove portion is fixed to a knitted fabric end portion, and the groove portion of the plate member is engaged with an appropriate frame material. After the end of the two-layered fabric spring material is welded, sewn, processed by resin, etc., the end is pressed with a holding member, etc., and fixed to the frame with bolts, etc., the end is folded back and sewn An arbitrary method such as a method of passing a metal rod through the hollow and fixing the metal rod to the frame can be used. In addition, by using a method of fixing the two-layer structure cloth spring material of the present invention to a frame via a metal spring such as a coil spring or a torsion bar, a cushioning property with a more stroke feeling can be imparted.

  The warp knitted fabric of the two-layer structure cloth spring material according to the present invention is preferably knitted using a Raschel knitting machine, and the gauge of the knitting machine is preferably 9 gauge to 28 gauge.

Basis weight of the two-layer structure cloth spring material, can be arbitrarily set depending on purposes, and preferably 300 to 1500 g / m ^2, more preferably 600~1200g / m ^2. More preferably 600~900g / m ^2.

  As a finishing method of warp knitted fabric of double-layered fabric spring material, the raw machine can be finished through processes such as scouring, dyeing and heat setting, but the scouring and dyeing process can be omitted and the raw machine can be finished only with heat set. You can also. In addition, finishing processing such as resin processing, water absorption processing, antistatic processing, antibacterial processing, and flame retardant processing, which are used in normal fiber processing, can be applied as long as the object of the present invention is not impaired at the time of finishing set. As the heat treatment machine used in the finishing set, a pin tenter, a clip tenter, a short loop dryer, a shrink surfer dryer, a drum dryer, a continuous or batch tumbler, or the like can be used. The cloth for the fabric spring after finishing can be used for a tension type seat or the like by processing the end by means of fusion, sewing, resin processing, or processing into a desired shape by thermoforming or the like. .

  In handling the two-layer structure fabric spring material, as a countermeasure against cut scraps that occur when the fabric is cut into a desired size with a scissor or a cutting machine, a coating process such as lamination is applied to the finished fabric, or heat fusion is performed in advance. A method is used in which the yarn to be worn is knitted to prevent the occurrence of cut scraps.

  Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited to these examples. In addition, the evaluation method and measurement of each characteristic in an Example were performed with the following method.

(1) Measurement of breaking strength Using an autograph tensile tester manufactured by Shimadzu, measured at a specimen length of 100 mm at a specimen length of 200 mm, a specimen width of 40 mm, and a tensile speed of 50 mm / min. The highest breaking strength was taken as the measured value.

(2) Measurement of tearing strength Using an autograph tensile tester manufactured by Shimadzu Corporation, the specimen length is 250 mm, the specimen width is 50 mm, and the tensile speed is 200 mm / min. A 100 mm cut is made in the length direction of the piece, the length is 100 mm cut at a width of 25 mm, the grip width is 50 mm, the test piece is measured between 100 mm in length, and the maximum tear strength obtained at that time is measured. did.

(3) Soft cushioning in the thickness direction (fitness, discomfort due to width, stability)
As the tension seat, a seat frame (no backrest) made of a mouth-shaped metal pipe material having a seat portion with a width of 520 mm, a depth of 470 mm, and a height of 320 mm was produced. A substantially U-shaped plate made of polybutylene terephthalate resin was sewn and attached to the entire width of the two sides in the longitudinal direction of the two-layer structure cloth spring material having a width of 500 mm and a length of 570 mm. One substantially U-shaped plate of the two-layer structure cloth spring material is engaged with a metal substantially U-shaped plate attached under the front edge of the seat frame, and a load of 10 kg is applied to the entire width of the two-layer structure cloth spring material. A two-layered cloth spring material is stretched before and after the seat frame with tension applied, and meshed with a metal substantially U-shaped plate under the rear edge of the seat frame with a resin-made substantially U-shaped plate. And stretched with a two-layer structure spring material. When the positions of the metal substantially U-shaped plate and the resin substantially U-shaped plate were shifted due to the tension of 10 kg, the position where the metal resin substantially U-shaped plate was bolted was shifted and adjusted. A male with a weight of 65 kg sat on the seat for 10 minutes after leaving the knee in the longitudinal direction of the two-layer structure cloth spring material, and then left the seat.

  The seating comfort at the time of sitting was evaluated. Soft cushioning as the comfort of the two-layered fabric spring material, ◎ “Moderate soft feeling and excellent cushioning properties”, ○ “Softness is slightly higher, or slightly harder and superior cushioning properties”, Δ Relative evaluation was made in four stages: “soft feeling is quite high or quite hard and inferior in cushioning properties”, and × “too soft or too hard and inferior in cushioning properties”.

(4) Amount of compression compression tearing Welded a foot of 15 cm high isometric iron to the corners of a metal plate with a thickness of 5 mm and a 40 cm square, and further 5 mm thick, 40 cm long and 5 width wide on the foot. The two metal plates of .5 cm were welded in parallel with the two opposite sides of the base to create a tension frame having a two-layer structure cloth spring material fixing portion. No. 40 sandpaper was affixed to the upper surface of the two-sided two-layer structure cloth spring material fixing portion with double-sided tape to provide anti-slip. On the other hand, a two-layer fabric spring material restraining material provided with anti-slip by sticking sandpaper No. 40 with double-sided tape to the lower surface of each of two metal plates having a thickness of 5 mm, a length of 40 cm, and a width of 5.5 mm. Created. Three materials were prepared by cutting a double-layered structure spring material into a 40 cm square and putting a scratch having a length of 25.4 mm in the biased (45 degree) direction at the center.

  A two-layer structure cloth spring material was sandwiched between two sides of the two-layer structure cloth spring material fixing portion and the presser material so as not to loosen, and a total of six locations were fixed and stretched with a vise.

  Using the Shimadzu Autograph AG-B type (manufactured by Shimadzu Corporation), the central part (25.4 mm scratched part) of the two-layer structure cloth spring material stretched by a metal 100 mm metal hemispherical compression jig Compressed at a speed of 50 mm / min, measured by first applying a load of 900 N, then applying a load of 2225 N, and then dehumidifying, then removing the double-layered fabric spring material from the metal frame and the size of the scratch ( The maximum length or size avoided was measured. The measurement was carried out three times to obtain an average value.

(5) Run generation After the measurement in (4) above, the length of run run from the scratched portion to the longest in the stitch direction (vertical, horizontal, slanting direction) was measured.

(6) Snacking property As a method for measuring the degree of occurrence of sink marks on the front and back surfaces of the two-layer structure cloth spring material, evaluation was made by a snack measurement method of JIS L1058D4 method. The worst snacking property with the most sink marks in the front and back surfaces and in the vertical and horizontal directions was collected as data.

(7) Cutting property The finished fabric was cut with scissors at intervals of 5 m in each of the vertical direction and the horizontal direction. When cutting, place a blackboard underneath, and visually evaluate it from the load and amount of scrap generated by cutting. ◎ “No load, less scratches”, ○ “There is no load, and scratches are generated.” , Δ “There is a load and there is a generation of scratches”, and × “It is difficult to cut and there are many generations of scraps after cutting.” × “relative evaluation.

[Example 1]
A 14 gauge, 6 mm double raschel knitting machine with 6 mm hooks was used. 167 decitex / 48 filament polyethylene terephthalate fiber false twisted yarn is supplied to the two ridges (L1, L2) that form the knitted fabric on the front side and the ridge (L3) that connects the front and back surfaces to form the knitted fabric on the back side. The cocoons (L4, L5) are fed with 688 dtex / 192 filaments and a polyethylene terephthalate fiber with a dry heat shrinkage rate of 12.9%. From the cocoon for insertion yarn (L6), 390 dtex manufactured by Solotex Corporation. Two monofilaments of polytrimethylene terephthalate fiber were fed together.

  The raw machine was knitted with the density of the on-machine course 15.02c / 2.54 cm with the knitting structure shown below. The obtained raw machine was dry-heat set at 170 ° C. × 3 minutes with a width to obtain a two-layer structure cloth spring material. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

(Knitting organization)
L1: 1011/1211 // (all in)
L2: 1211/1011 // (all in)
L3: 1210/2123 // (all in)
L4: 1110/0001 // (all-in)
L5: 3310/3356 // (all-in)
L6: 4444/0000 // (all-in)
The obtained two-layer fabric spring material has strong breaking strength and high tearing strength that makes it difficult to run the cut yarn, has an excellent flexibility and a good fit, has no discomfort in the buttocks, and has an excellent sense of stability. Sitting comfort was obtained. In addition, the recovery was shown to recover completely.

[Example 2]
In Example 1, a two-layered structure spring material was obtained in the same manner as in Example 1 except that the L4 knitting structure for knitting the ground structure was as follows. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material. The obtained two-layer fabric spring material has strong breaking strength and high tearing strength that makes it difficult to run the cut yarn, has an excellent flexibility and a good fit, has no discomfort in the buttocks, and has an excellent sense of stability. Sitting comfort was obtained. In addition, the recovery was shown to recover completely.

(Knitting organization)
L4: 1110/1123 //

[Example 3]
In Example 1, except that 500 ttex 144 filament polyethylene terephthalate fiber false twisted yarn was supplied to the two ridges (L1, L2) forming the front knitted fabric and the ridge (L3) connecting the front and back surfaces. A two-layer fabric cloth material similar to 1 was obtained. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The resulting two-layer fabric spring material has strong breaking strength and high tearing strength that makes it difficult for the cut yarn to run, moderate flexibility, good fit, almost no discomfort in the buttocks, and excellent stability Sitting comfort was obtained. In addition, the recovery was almost restored.

[Example 4]
In Example 1, 330 dtex 96 filament polyethylene terephthalate fiber false twisted yarn is supplied to the two ridges (L1, L2) forming the front side knitted fabric and the ridge (L3) connecting the front and back surfaces, and the ground structure is knitted. A two-layer fabric spring material was obtained in the same manner as in Example 1 except that the L5 knitting structure was changed as follows. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The resulting two-layer fabric spring material has strong breaking strength and high tearing strength that makes it difficult for the cut yarn to run, moderate flexibility, good fit, almost no discomfort in the buttocks, and excellent stability Sitting comfort was obtained. In addition, the recovery was almost restored.

(Knitting organization)
L5: 3310/3345 //

[ Reference Example 5]
A fabric spring fabric was obtained in the same manner as in Example 1 except that 33 dtex 12 filament polyethylene terephthalate fiber was supplied to the ridge (L3) connecting the front and back surfaces. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The obtained two-layer structure cloth spring material was slightly inferior in seating stability and recoverability as compared with Example 1.

[Comparative Example 1]
In Example 1, a cloth for a cloth spring was obtained in the same manner as in Example 1 except that a false twisted yarn of polyethylene terephthalate fiber of 1200 dtex 300 filaments was supplied to the ridge (L3) connecting the front and back surfaces. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The resulting two-layer structure cloth spring material had a good seating stability, but had a strong and uncomfortable feeling as a two-layer structure cloth spring material. Furthermore, the knitting property was also bad.

[Comparative Example 2]
In Example 1, except that the knitting structure of the ridges (L4, L5) forming the ground structure on the back surface was changed to the following, an attempt was made to obtain a two-layered fabric spring material similar to Example 1, but the knitting The fabric was not obtained due to the poor nature and frequent thread breaks.

(Knitting organization)
L1: 2210/2234 //
L2: 3310/3367 //

[Comparative Example 3]
In Example 1, a two-layer structure cloth spring material was obtained in the same manner as in Example 1 except that the distance between the hooks was 3 mm. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The obtained two-layer structure cloth spring material had no surface rigidity, was inferior in stability, and had poor recoverability after sitting.

[Comparative Example 4]
In Example 1, a two-layer structure cloth spring material was obtained in the same manner as in Example 1 except that the distance between the hooks was 14 mm. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The obtained two-layer structure cloth spring material had no surface rigidity, was inferior in stability, and had poor recoverability after sitting.

[Comparative Example 5]
In Example 1, a fabric for a fabric spring was obtained in the same manner as in Example 1 except that monofilament yarn of 390 dtex polytrimethylene terephthalate fiber was supplied to the ridge (L3) connecting the front and back surfaces. Table 1 shows various physical properties of the obtained two-layer structure cloth spring material.

  The obtained two-layered fabric spring material had poor seating stability and recoverability, and the run ran through the fabric by tension compression tearing with monofilament sliding.

Claims (7)

It is a two-layer structure cloth spring material in which two layers of front and back knitted fabrics are connected by connecting yarns that are false-twisted with 100% multifilament yarn, and the finished fabric has a thickness of 2.0 to 5.0 mm A double-layered structure spring material characterized in that the knitted fabric has a breaking strength in the warp direction and the transverse direction of 600 N or more and a tear strength of 150 N or more.   Of the two layers of the front and back, one of the knitted fabrics is composed of at least two knitted loop structures, one fold is composed of chain knitting or tricot knitting with two or less stitches, and the other ridge is The two-layer structure cloth spring material according to claim 1, wherein the two-layer structure cloth spring material is constituted by a tricot knitting of 1 stitch or more and 8 stitches or less.   The two-layer structure cloth spring material according to claim 1 or 2, wherein the warp yarn inserted in the warp direction is inserted in the same direction or in a different direction with respect to the other chain knitting or tricot knitting.   The two-layer structure cloth spring material according to any one of claims 1 to 3, wherein a fineness of a multifilament yarn connecting the knitted fabrics of the two layers of the front and back is 50 dtex or more and 1000 dtex or less.   The two-layer structure cloth spring material according to any one of claims 1 to 4, wherein the multifilament yarn that connects the two knitted fabrics of the front and back surfaces is a bulky processed yarn. The knitted fabric of the two layers is connected by multifilaments, and the cover factor of the knitted fabric composed of the multifilament connecting yarn and the surface yarn is 5 × 10 ⁴ or more and 5 × 10 ⁵ or less. The two-layer structure cloth spring material according to any one of claims 1 to 5.   The two-layer structure cloth spring material according to any one of claims 1 to 6, wherein the tension compression tear amount is within 20 mm.