Woven fabric and manufacturing method thereof

Abstract

To provide a high-quality and high-density woven fabric which has the occurrence of edge flare during weaving suppressed, has the occurrence of wrinkles in a coating process suppressed, has excellent uniform coating properties, and has positional deviation during cutting suppressed, and to provide a method for manufacturing the high-quality and high-density woven fabric.SOLUTION: In a woven fabric made of synthetic fibers, the woven fabric has: a cover factor of 2000 or more; a first maximum value WP1 of warp densities within a range of 2 to 7 mm from a fabric edge and a second maximum value WP2 of warp densities within a range of 7 to 15 mm from the fabric edge in at least one selvage of the woven fabric; and WP1 / Nw of 1.20 to 1.35 and WP2 / Nw of 1.1 to 1.2 with a warp density of a ground part as Nw.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a fabric and a method for manufacturing the fabric. More specifically, the present invention relates to a fabric with small ear flares and high quality and high density, and a method for manufacturing a fabric for weaving such a fabric.

Background Art

[0002] In the fields of sports and industrial materials applications, etc., there is an increasing demand for increasing the density of fabrics for the purpose of improving quality (for example, increasing strength, improving water repellency, reducing air permeability, improving seam slippage, etc.). Also, along with the improvement of the performance of weaving machines, the cost competition for generalizing high-density fabrics has become fierce. Therefore, the development of high-density weaving technology is required.

[0003] For example, an airbag for an automobile is generally made by manufacturing a base fabric (so-called coated fabric) in which a resin such as silicone is applied or laminated to a fabric made of a plain weave fabric using synthetic fibers of 150 to 600 dtex in order to improve characteristics such as heat resistance, flame retardancy, and air barrier properties, cutting this, and sewing it into a bag body. Also, there is a so-called non-coated fabric that is used by reducing the air permeability of the fabric by weaving synthetic fiber filament yarns such as polyamide fibers at a high density without applying a resin to the base fabric.

[0004] When the density of a fabric increases, the friction between the warp and weft during weaving increases. Therefore, during reed beating, it becomes difficult to drive the weft in. As a result, before the fabric is formed on the loom, it moves in the reed direction and "ejection" occurs. In particular, for high-density fabrics, the ejection becomes larger, and as a result, the vibration of the loom increases, the load on the warp increases, and it becomes easy to induce hairiness and yarn breakage. Also, when the density increases, the insertion space for the weft becomes smaller, so the manufacturing operation is easily interrupted due to weft insertion errors.

[0005] In addition, when the forced extraction becomes large, the warp slack in the ear part of the base fabric becomes large, a difference in fabric length occurs between the ear part and the central part, and a flare (also referred to as "ear flapping") in which the ear end part becomes wavy occurs. The occurrence of the flare causes various inconveniences in the use of the fabric. For example, a fabric for an airbag is cut and sewn to form a bag body. In this case, in order to make the maximum effective use of the airbag fabric, a cutting pattern is designed and usually used up to the ear end part or its vicinity. Since the ends of the cut pieces are likely to fray, if a flare occurs in the vicinity of the ear end part, cutting defects are likely to occur. As a result, the desired exact shape as an airbag cannot be obtained, and the required functions are also lost. In addition, when coating is performed after manufacturing the fabric, if a flare occurs, it may cause a difference in the coating amount of the coating resin between the ground part and the ear part, and may also cause wrinkles in the ear part during winding.

[0006] As various attempts to prevent forced extraction and ear flare, in a base fabric for an airbag made of a synthetic fiber fabric, a method of making the fineness of the warp yarns in the ear part of the fabric thinner than the fineness of the warp yarns in the main body of the base fabric (Patent Document 1), a method of inserting additional yarns in addition to the ply yarns or a method of changing the ply yarn structure (Patent Documents 2 to 5), etc. have been proposed.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Patent Document 5

Summary of the Invention

Problems to be Solved by the Invention

[0008] According to the technology described in Patent Document 1, since a yarn with a fine fineness is used for the ear part, when winding the warp beam, unevenness occurs on the beam surface due to the fineness difference, and there is a problem that the warps fed out during weaving become loose. According to the technologies described in Patent Documents 2 to 4, there is a problem that the extrusion and flare in the end region are not sufficiently suppressed in order to adjust the winding yarn and the increased yarn inserted into the ear end of the fabric. Further, the technology described in Patent Document 5 is a technology for weaving with a ring template, which can suppress the generation of ear flare of a coated airbag with a cover factor of less than 2000, but when weaving a high-density fabric with a cover factor of 2000 or more, the extrusion becomes large, and problems such as ear tearing are likely to occur and weaving is difficult.

[0009] The present invention has been made in view of such conventional problems, and an object thereof is to provide a high-quality high-density fabric that suppresses the extrusion generated during weaving and has a small ear flare. Another object of the present invention is to provide a method for manufacturing the above high-quality high-density fabric by reducing the extrusion.

Means for Solving the Problems

[0010] In order to solve the above problems, the present invention has the following configuration (1). (1) A fabric made of synthetic fiber, having a cover factor of 2000 or more, and in at least one ear part of the fabric, having a first maximum value WP1 of warp density within a range of 2 to 7 mm from the fabric end, and a second maximum value WP2 of warp density within a range of 7 to 15 mm from the fabric end, and characterized in that WP1 / Nw is 1.20 to 1.35 and WP2 / Nw is 1.1 to 1.2 with respect to the warp density Nw of the ground part. In such a fabric of the present invention, preferably, it has the following configuration (2). (2) The fabric according to (1) above, which is a fabric for an airbag.

[0011] Further, the manufacturing method of the fabric of the present invention has the following configuration (3) in order to solve the above problems. (3) A manufacturing method for manufacturing the fabric according to any one of (1) to (2) above, which uses a loom template device for gripping the fabric during weaving. The loom template device includes a ring template device for gripping both ears of the base fabric and a full-width template device for gripping the entire fabric with a fabric gripping bar. The full-width template device is arranged on the winding side rather than the ring template device, and the fabric gripping bar has both a left screw portion and a right screw portion. A method for manufacturing a fabric, characterized in that.

Effect of the Invention

[0012] The fabric obtained from the manufacturing method of the present invention has a small ear flare, so it provides a high-quality high-density fabric with little undulation during fabric lamination in the cutting and sewing processes and no occurrence of defects such as wrinkles and cutting defects.

[0013] According to the manufacturing method of the fabric of the present invention, there is provided a manufacturing method of a fabric that enables the weaving of a high-density fabric excellent in such quality and process passability.

Brief Explanation of Drawings

[0014]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Embodiment for Carrying Out the Invention

[0015] [Fabric] The fabric of the present invention has a ground portion made of synthetic fiber multifilaments (hereinafter also referred to as synthetic fiber yarns). Here, the ground portion refers to the portion of the fabric body other than the ear portion. For example, the portion excluding 20 cm at both ends in the width direction of the fabric is generally treated as the ground portion of the fabric. As the synthetic fiber, for example, polyamide-based fibers, polyester-based fibers, aramid-based fibers, rayon-based fibers, polysulfone-based fibers, or ultra-high molecular weight polyethylene-based fibers can be used. Among them, polyamide-based fibers and polyester-based fibers, which are excellent in mass productivity and economy, are preferred.

[0016] Examples of polyamide-based fibers include fibers composed of nylon 6, nylon 66, nylon 410, nylon 46, copolymer polyamides of nylon 6 and nylon 66, and copolymer polyamides obtained by copolymerizing nylon 6 with polyalkylene glycol, dicarboxylic acid, amine, etc. Nylon 6 fibers and nylon 66 fibers are particularly excellent in strength and are preferred.

[0017] Examples of polyester-based fibers include fibers composed of polyethylene terephthalate, polybutylene terephthalate, etc. Fibers made of copolymer polyesters obtained by copolymerizing polyethylene terephthalate or polybutylene terephthalate with aliphatic dicarboxylic acids such as isophthalic acid, 5-sodium sulfoisophthalic acid, and adipic acid as acid components may also be used.

[0018] The fabric of the present invention preferably usually uses the same synthetic fiber yarn as the warp and weft. Using the same synthetic fiber yarn as the warp and weft means that both the warp and weft are made of the same kind of polymer, have the same single fiber fineness, and have the same total fineness. The same kind of polymer refers to polymers whose main repeating units are common, such as nylon 66, polyethylene terephthalate, etc.

[0019] The synthetic fiber yarns (warp and weft) used as the fabric of the present invention are preferably synthetic fiber filaments with a single fiber fineness of 0.5 to 7 dtex. By setting the single fiber fineness to 7 dtex or less, the voids between the single fibers in the fabric become smaller, and the fiber filling effect is further improved, so that the air permeability can be preferably reduced. In addition, when the single yarn fineness is small, the rigidity of the synthetic fiber filament decreases, and the effect of improving the flexibility of the fabric can also be obtained. For example, when used as a fabric for an airbag, the storability is improved, which is preferable.

[0020] The total fineness of the synthetic fiber yarns used as the fabric is preferably 30 to 550 dtex. By setting the total fineness of the synthetic fiber yarns to be used to 30 dtex or more, the strength of the fabric is maintained. In addition, by setting the total fineness to 550 dtex or less, the compactness during storage and the low air permeability can be maintained. The total fineness is more preferably 50 to 500 dtex. By setting the total fineness within this range, the tear strength, slippage resistance, low air permeability, flexibility, and compact storability of the fabric can be improved in a well-balanced manner.

[0021] The fabric of the present invention is composed of warp and weft yarns made of the same synthetic fiber yarn as described above, and the fabric texture is not particularly limited. For example, fabric textures include plain weave, twill weave, satin weave, and their variations, multi-axis weave, etc. Among these, plain weave is particularly preferred because of its excellent mechanical properties and thin ground. The fabric density can vary depending on whether the fabric is resin-processed or not, and also on the fineness of the weaving yarns, etc. However, a cover factor of 2000 - 2200 is preferred for achieving both low air permeability and high slippage resistance. Generally, if the cover factor is within the above range, the mechanical properties (tensile strength, tear strength, etc.) required for the fabric are appropriately maintained, and it is easy to achieve an appropriate areal density and difficult to become coarse and hard. When the cover factor is less than 2000, the areal density of the fabric tends to be small and misalignment is likely to occur. On the other hand, when the cover factor exceeds 2200, the areal density of the fabric tends to be large and it tends to become coarse and hard. Generally, when the cover factor exceeds 2000, the recession of the weaving mouth at the ear part, which becomes a problem during weaving, becomes large. Also, the flare becomes prominent. The present invention can be effectively adopted even for fabrics with a cover factor less than 2000 or exceeding 2200. In particular, for fabrics with a cover factor of 2000 - 2200, the above effects are easily achieved. In the present invention, the cover factor (CF) is a value calculated from the total fineness of the yarn used for the warp or weft and the fabric density, and is defined by the following formula (1). In formula (1), Dw is the total fineness of the warp yarn (dtex), Nw is the warp density (ends per 2.54 cm), Df is the total fineness of the weft yarn (dtex), and Nf is the weft density (ends per 2.54 cm). CF=(Dw) 1 / 2 ×Nw+(Df) 1 / 2 ×Nf ··· (1) The fabric of the present invention has a first maximum value WP1 of the warp density within the range of 2 - 7 mm from the fabric end, and a second maximum value WP2 of the warp density within the range of 7 - 15 mm from the fabric end, at least in one of the ear parts of the fabric, and is characterized in that WP1 / Nw is 1.20 - 1.35 and WP2 / Nw is 1.1 - 1.2 with respect to the warp density Nw of the ground part. The maximum values WP1 and WP2 of the warp density occurring in the range of 2 to 7 mm from the fabric edge and in the range of 7 to 15 mm from the fabric edge are related to the positions of the first ring and the second ring when using a ring template. Generally, the ring template is installed such that the needles provided on the first ring and the second ring are within the range of 1 to 15 mm from the fabric edge. At the fabric edge, the contraction of the fabric in the width direction is suppressed by the needles provided on the first ring and the second ring of the ring template, and the stress acts on the warp near the fabric edge. As a result, a bias occurs in the interval between the warps, and the maximum value of the warp density is generated. When the maximum value of the warp density occurs, the interlacing structure between the yarns becomes strong due to the high fabric density in that part, and the flare is easily suppressed. When WP1 / Nw and WP2 / Nw, which are the ratios of the warp density of the ground part to the maximum values at the fabric edge, are within the above range, the obtained fabric has a small ear flare. When WP1 / Nw and WP2 / Nw are smaller than the above range, the stress for suppressing the contraction of the fabric in the width direction during weaving is insufficient, the interlacing structure between the yarns at the fabric edge becomes loose, and the ear flare is likely to deteriorate. When WP1 / Nw and WP2 / Nw are larger than the above range, the interlacing structure between the yarns at the fabric edge becomes strong, but ear hanging is likely to occur at the fabric edge, and when the fabric is laminated and cut, the distortion caused by the difference in the structure between the ground part and the ear part of the fabric overlaps, and the waviness of the fabric is likely to occur.

[0022] Generally, when weaving a fabric, at the ear part, winding yarns or additional yarns are used at the ear tips. The "winding yarns", also called leno, are used to prevent ear fraying. At the outermost side of the ear part of the fabric, multiple yarns are intertwined while tightening the weft yarns to form the ear part. When forming the ear, generally a planetary gear mechanism is used, and more preferably a planetary gear twisting method is used. Other methods may also be used to form the ear part. The material, type, and fineness of the winding yarns are appropriately selected according to the type of the ground yarn and the weaving density. The number of yarns used is preferably 2 or more at each of both ends, preferably 2 at each end. Generally, monofilaments with excellent ear tightening performance are used as the winding yarns. Multifilaments may also be used as the winding yarns. Preferably, the material of the winding yarns is the same as that of the ground yarn. The fineness of the winding yarns is preferably 33 dtex or less. When the fineness exceeds 33 dtex, fraying may occur at the ear part of the fabric. The fineness of the winding yarns is preferably 5 - 22 dtex.

[0023] Similar to the winding yarns, the "additional yarns" are used for the purpose of preventing fraying at the ear part of the fabric, and are arranged between the winding yarns and the warp yarns at the ear part of the fabric to assist the winding yarns. However, a planetary device is not used for the additional yarns. It is preferably used in a plain weave with excellent ear tightening property. Also, the material, type, and fineness of the additional yarns are each appropriately selected according to the type of the ground yarn and the weaving density. Similar to the above-mentioned winding yarns, monofilaments with excellent ear tightening performance are preferably used as the additional yarns. The number of additional yarns used, when used, is, for example, 2 to 12 at each of both ends. The fineness of the additional yarns is preferably 33 dtex or less. When the fineness exceeds 33 dtex, fraying may occur at the ear part of the fabric. The fineness of the winding yarns is preferably 5 - 22 dtex.

[0024] [Method for manufacturing a fabric] The following steps shown as the method for manufacturing the fabric of the present invention are all examples and may be replaced by other known steps.

[0025] According to the method for manufacturing a fabric of the present invention, first, the warp yarns with the above-mentioned total fineness related to the fabric are warped and installed on a loom. Similarly, the weft yarns are installed on the loom. Examples of the loom include a water jet loom, an air jet loom, a rapier loom, etc. Among these, from the viewpoint that high-speed weaving is relatively easy and productivity can be easily increased, a water jet loom is preferable as the loom.

[0026] During weaving, the tension applied to each warp yarn constituting the ground portion of the fabric is preferably adjusted to be in the range of 0.2 to 0.5 cN / dtex. When the warp tension is within the above range, the resulting fabric can improve dimensional stability by reducing the voids between the single fibers in the multifilament yarn bundle constituting the fabric. When the warp tension is less than 0.2 cN / dtex, the restraining force of the weft yarn during weaving is low, and it is difficult to obtain a fabric with the same density of warp and weft. On the other hand, when the warp tension exceeds 0.5 cN / dtex, in the fabric, the contact area (adhesion) between the warp and weft yarns tends to be large. Therefore, the warp yarns are likely to have hairiness, and the weaving property is likely to be inferior. The method for adjusting the warp tension is not particularly limited. For example, the warp tension can be adjusted by a method of adjusting the warp delivery speed of the loom, a method of adjusting the driving density of the weft yarn, etc. Whether the warp tension is within the above range can be confirmed, for example, by measuring the tension applied to each warp yarn with a tension measuring device at the central portion between the warp beam and the back roller during loom operation.

[0027] The loom template device in the method for manufacturing a fabric of the present invention will be described in detail. FIG. 1 is a schematic plan view of the loom template device of the present embodiment. It mainly includes a plurality of warp threads 1 aligned in the vertical direction, a reed 2 through which the warp threads 1 pass, a ring template device 6 disposed on the downstream side of the reed 2, a full-width template device 7 disposed on the downstream side of the ring template device 6, a weft nozzle 3 disposed between the reed 2 and the ring template device 6, a weft thread 4 appropriately fed out from the weft nozzle 3 in a direction orthogonal to the warp threads 1 and inserted between the warp threads 2, and a weft cutter 5 for cutting the weft thread 4 driven by the reed 2. The fabric 8 formed by being driven by the reed 2 is first gripped by the ring template device 6 so as to suppress the contraction in the width direction of both ear portions. Further, it is gripped by the full-width template device 7 disposed on the downstream side so as to suppress the contraction in the width direction and the longitudinal direction. The ring template device 6 is a device for preventing wear of the reed 2 and breakage of the warp threads due to weaving shrinkage before weaving during weaving, and is attached before weaving. When the weft thread 4 is driven in, the fabric 8 is pushed into the downstream side, and at the same time as the reed returns to the upstream side, the fabric 8 also tries to return to the upstream side. At this time, the pushing-back of the fabric 8 with respect to the most forward position of the reed is the protrusion 9. The full-width template device 7 is a device for gripping the fabric on the downstream side (the winding side with respect to the ring template device) of the ring template device in order to suppress the pushing-back (protrusion) of the fabric. After passing through the full-width template device 7, the fabric 8 is further wound by a winding device (not shown) disposed on the downstream side. In the method for manufacturing a fabric of the present invention, the loom template device includes a ring template device for gripping both ears of the base fabric, and a full-width template device for gripping the entire fabric by a fabric gripping bar disposed on the winding side with respect to the ring template device. Further, the full-width template part fabric gripping bar has both a left-threaded shape part and a right-threaded shape part.

[0028] FIG. 2 is a schematic diagram for explaining a prior art temple device for a loom. The full-width temple device 7 is attached near the most advanced position of the reed, so that the squeezing-out 9, which is the backward movement of the fabric 8, is effectively suppressed. On the other hand, with only the full-width temple device, both ear portions are not gripped and the shrinkage in the width direction is not sufficiently suppressed. Therefore, the shrinkage of the fabric at the ear portions in particular becomes large and flare is likely to occur.

[0029] FIG. 3 is a schematic side view of the full-width temple device 7 of the present embodiment. The temple device 7 of the present embodiment mainly includes a fabric gripping bar 10 for gripping the fabric 8 during weaving, and a pair of upper and lower gripping members (support member 11 and pressing member 12) extending across the entire width of the fabric 8. In such a full-width temple device 7, the fabric 8 is introduced so as to be gripped by the support member 11 and the fabric gripping bar 10. The fabric 8 introduced into the full-width temple device 7 is wound around the outer peripheral surface of the fabric gripping bar 10. Further, the fabric 8 is gripped by the fabric gripping bar 10 and the pressing member 12, and is led out in the winding direction along the upper surface of the pressing member 12. At this time, the fabric 8 is under tension by a winding device disposed on the downstream side of the full-width temple device 7. Therefore, the fabric gripping bar 10 around which the fabric 8 is wound is moderately pressed against the support member 11 and the pressing member 12.

[0030] When the weft yarn 4 is driven into the reed 2, the fabric gripping bar 10 moves slightly in the reed driving direction A1, so that the force with which the fabric 8 is gripped by the support member 11 and the pressing member 12 is temporarily weakened. At this time, the fabric 8 is fed out as the fabric gripping bar 10 rotates and is moved in the reed driving direction A1. Thereafter, the fabric 8 is again tensioned by the take-up device. As a result, the fabric gripping bar 10 moves to the upstream side in the reed driving direction A1 and is again pressed against the support member 11 and the pressing member 12. In such a loom and the full-width temple device 7, the rear end portion (before weaving) of the fabric 8 formed by the reed-driven weft yarn 4 moves to the upstream side in the reed driving direction A1, and a protrusion 9 may occur (see FIG. 1). In particular, in the end region in the width direction of the fabric, the protrusion 9 is more likely to be larger than in the central region. When the protrusion 9 becomes large, the warp yarns of the fabric become loose particularly in the end region, and in addition to density unevenness and air permeability unevenness, hairiness is likely to occur. When hairiness occurs in the fabric, the weaving operation may stop. Therefore, suppressing hairiness can not only improve the quality of the obtained fabric but also contribute to reducing the manufacturing cost. In the present embodiment, the size of the protrusion 9 (protrusion amount a) refers to the position when the reed 2 is located at the most downstream side in the reed driving direction A1 in the stroke in which the reed 2 operates and when the reed 2 advances from the upstream side to the downstream side in the reed driving direction A1 and the reed 2 contacts the rear end portion (before weaving) of the fabric 8 (see the protrusion amount a in FIG. 1). The full-width temple device 7 of the present embodiment suppresses such a protrusion 9 generated during reed beating. Hereinafter, each configuration will be described. Note that the full-width temple device 7 of the present embodiment is characterized by the fabric gripping bar 10. Therefore, the other configurations (such as the support member 11 and the pressing member 12) shown below are examples, and other known configurations may be adopted.

[0031] (Support member 11) The support member 11 is a member to which the fabric gripping bar 10 and the pressing member 12 are attached, and is fixed to the support base 13. The support member 11 includes a mounting portion 11a attached to the support base, an edge portion 11b extending obliquely upward on the upstream side in the reed beating direction A1 from the end of the mounting portion 11a, and an engaged portion 11c formed above the mounting portion 11a. The engaged portion 11c is a substantially flat plate-shaped member formed on the upper surface of the mounting portion 11a, and a recess recessed in the reed beating direction A1 is formed on the side surface. The engaging portion 12b of the pressing member 12 described later is engaged with the recess.

[0032] (Pressing member 12) The pressing member 12 is a member for gripping the fabric gripping bar 10 together with the support member 11, and includes a substantially flat pressing portion main body 12a and an engaging portion 12b extending obliquely downward on the downstream side in the reed beating direction A1 from the lower surface of the pressing portion main body 12a. Among the pressing portion main body 12a, the upstream end portion in the reed beating direction A1 is curved downward obliquely on the upstream side in the reed beating direction A1 (curved portion). The pressing member 12 and the support member 11 are arranged such that the end portions of the curved portions are separated from each other, and the fabric gripping bar 10 is prevented from falling off on the upstream side in the reed beating direction A1. The engaging portion 12b is slightly smaller in dimension than the recess of the engaged portion 11c and is fitted into the recess. Therefore, the pressing member 12 can rotate by a predetermined angle with the engaging portion 12b as a fulcrum in a state where the engaging portion 12b is fitted into the recess.

[0033] (Fabric gripping bar 10) The fabric holding rod 10 is a rod-shaped member for holding the fabric 8 during weaving. FIG. 4 is a schematic plan view of the fabric holding rod 10 provided in the full-width template device 7 of the present embodiment. The fabric holding rod 10 includes a left screw portion 14 of the fabric holding rod and a right screw portion 15 of the fabric holding rod. The pitch and lead of the threaded portion of the fabric holding rod 10 are not particularly limited, but it is preferably a single-thread shape with the same pitch and lead, and the range of the pitch and lead is preferably 0.75 to 3 mm. When the fabric 8 passes through the full-width template device 7 of the present embodiment, the fabric holding rod 10 rotates. At this time, due to the threaded shape on the surface of the fabric holding rod, a force acts on the fabric 8 in the width direction of the fabric. For example, when looking from the downstream side to the upstream side in the reed beating direction A1 (the state in FIG. 4), by providing the left screw portion 14 of the fabric holding rod on the left side and the right screw portion 15 of the fabric holding rod on the right side of the fabric, a force acts on the fabric 8 so that the width expands when passing through the full-width template 7. On the other hand, when the configuration of the threaded portion of the fabric holding rod is reversed, with the right screw portion 15 of the fabric holding rod provided on the left side and the left screw portion 14 of the fabric holding rod provided on the right side (a state opposite to FIG. 4), a force acts on the fabric 8 in the direction of narrowing the width. By applying a force so that the width expands when the fabric 8 passes through the full-width template 7, the fabric shrinkage in the front weaving part is suppressed, so that the backward movement of the weaving mouth and the occurrence of flare before weaving during weaving can be effectively suppressed.

[0034] Regarding the surface shape of the fabric holding rod 10, the surface shape can be changed by performing surface finishing such as smooth processing or satin processing to adjust the holding force of the fabric. However, in order to improve the shrinkage in the width direction of the fabric, it is preferable to have both a left screw-shaped portion and a right screw-shaped portion. The lengths of the left screw portion 14 of the fabric holding rod and the right screw portion 15 of the fabric holding rod are not particularly limited. However, from the viewpoint of making the force for the fabric 8 to move in the width direction uniform on the left and right, it is preferable to keep the difference in length between the left screw portion 14 of the fabric holding rod and the right screw portion 15 of the fabric holding rod within 10%. More preferably, by making the difference in length between the left screw portion 14 of the fabric holding rod and the right screw portion 15 of the fabric holding rod within 1%, the force applied to the fabric 8 and the fabric holding rod 10 can be made uniform.

[0035] By the above weaving method, the extrusion generated during weaving can be suppressed, and a fabric having WP1 and WP2, where WP1 / Nw is 1.20 - 1.35 and WP2 / Nw is 1.1 - 1.2, can be obtained, resulting in a high-quality high-density fabric with small ear flares.

[0036] After weaving is completed, the obtained fabric is subjected to a drying treatment if necessary. The drying temperature is usually 80°C or higher. When the drying temperature is 80°C or higher, the fabric has a small dry heat shrinkage rate and improved dimensional stability.

[0037] Next, the fabric is appropriately subjected to processes such as scouring and heat setting. In the scouring process, the scouring temperature is preferably 20°C or higher, more preferably 25°C or higher. Also, the scouring temperature is preferably 80°C or lower, more preferably 70°C or lower. When the scouring temperature is 20°C or higher, the residual strain in the fabric is removed, the single fiber filaments within the multifilament become more mobile, and the multifilament can spread flat against the fabric. Therefore, the dimensional stability of the fabric can be improved. Also, when the scouring temperature is 80°C or lower, significant shrinkage of the multifilament is suppressed. As a result, the dimensional stability of the fabric can be improved.

[0038] The heat setting temperature in heat setting is preferably a temperature that can remove the strain remaining in the fabric after weaving and suppress significant shrinkage of the multifilament, similar to scouring. Specifically, the heat setting temperature is preferably 150°C or higher, more preferably 160°C or higher. Also, the heat setting temperature is preferably 190°C or lower. When the heat setting temperature is within the above range, the resulting base fabric can have improved dimensional stability.

[0039] The fabric that has undergone the above processes may be appropriately coated with a resin or an elastomer. By applying a coating to the fabric of the present invention, airtightness can be imparted. When applying a coating, the coating amount is preferably about 5 to 35 g / m2. As the resin or elastomer, those having heat resistance, cold resistance, and flame retardancy are preferable. As the resin or elastomer, for example, silicone resin, polyamide resin, polyurethane resin, fluororesin, etc. are preferably used.

[0040] The fabric that has undergone the above processes may be appropriately subjected to ear cutting. By subjecting the fabric of the present embodiment to ear cutting, it becomes easy to adjust the position during cutting. As the part of the fabric to be discarded by ear cutting, the warp yarns from the ear end of the fabric to about 25 mm from the ear end where the pin holes are formed by the entangled yarns, increased yarns, ear tightening yarns, and heat setting are cut. By cutting the parts that are not used as the fabric of the ear part, the number of laminatable sheets in the cutting process can be increased, and the cutting efficiency can be improved.

[0041] As described above, according to the method for manufacturing the fabric of the present invention, it is possible to suppress the occurrence of the protrusion of the ear end portion during fabric weaving and to reduce the ear flare. In particular, when used as a fabric for an airbag, it is possible to provide a fabric for an airbag that is excellent in the processing passability and uniform coating property in the scouring, setting, and further coating processes performed after weaving, and is also excellent in cuttability and sewability.

Example

[0042] Hereinafter, the present invention will be specifically described by way of examples. The present invention is not limited to these examples. In the following examples, each characteristic value was calculated by the following method.

[0043] <Calculation method of characteristic value> (Total fineness) The total fineness was calculated by measuring the linear density at a predetermined load of 0.045 cN / dtex according to Method A of JIS L1013:2010 8.3.1.

[0044] (Number of filaments) The number of filaments was calculated based on the method of JIS L1013:2010 8.4.

[0045] (Denier per filament) The denier per filament was calculated by dividing the total denier by the number of filaments.

[0046] (Weave density) For each of the warp and weft weave densities, the fabric surface at the central part and both ear ends in the width direction of the fabric was photographed with an optical microscope, and the weave density was calculated from the distance between adjacent yarns, and the local density distribution of the weave density was measured. Specifically, the weave density was calculated from the width of a total of five warps including two warps adjacent to each warp in the measurement part, and this was taken as the warp density in the measurement part. For the central part of the fabric, the weave density of the warp or weft was measured, and the average value of each three points was calculated and taken as Nw or Nf, respectively.

[0047] For both ear ends of the fabric, the warp density was measured at 1 mm intervals from the fabric end up to 30 mm, and the distribution of the warp density was measured by plotting the distance from the fabric end on the horizontal axis and the warp density on the vertical axis in a graph. Fig. 5 is an example of a graph plotting the warp density against the distance from the fabric end, which is a characteristic of the fabric of the present invention. The maximum values of the warp density within the ranges of 2 to 7 mm or 7 to 15 mm from the fabric end were taken as the first maximum value WP1 and the second maximum value WP2, respectively.

[0048] (Areal density) The areal density was calculated based on JIS L 1096:2010 8.3.2 by collecting three test pieces of 20 cm × 20 cm, weighing the mass (g) of each, and converting the average value to the mass per 1 m 2 per (g / m 2 ).

[0049] (Weaving start timing) In a loom, a series of periodic motions of the loom, in which the reed retreats from the foremost position, the weft is inserted into the opened warp threads, and the reed advances to beat in the weft, are represented by the rotational angle of the loom from 0° to 360°. With the state where the reed is in the foremost position being defined as the rotational angle of 0°, the rotational angle at the moment when the fell of the cloth contacts when the reed beats in the weft is measured and used as the fell contact timing. The fell contact timing is measured by applying a timing light for the loom when the loom is operating to weave a fabric, and is measured at the ground part in the center of the fabric and at the respective ear parts on the weft feeding side and the weft non-feeding side. For the ear parts, the average value of the feeding side and the non-feeding side is calculated. The evaluation of the fell recession is determined with the difference between the ground part and the ear parts as the magnitude of the fell recession. Less than 3° is rated as "S", 3° or more and less than 6° is rated as "A", 6° or more and less than 8° is rated as "B", and 8° or more is rated as "C".

[0050] (Presence or absence of occurrence of ear flare of fabric) The woven fabric is cut to a length of 1 m and spread out on a flat table, and the height of the most raised part of the ear part is measured in 1 mm increments (amounts less than 1 mm are rounded off), and the average value of both ear parts is calculated. The evaluation is determined with the ear flare height as the magnitude. Less than 8 mm is rated as "S", 8 mm or more and less than 10 mm is rated as "A", 10 mm or more and less than 12 mm is rated as "B", and 12 mm or more is rated as "C". Also, a fabric with ear collapse is rated as "-".

[0051] <Example 1> (Warp, weft) As the warp and weft, synthetic fiber filaments made of nylon 66, having a circular cross-sectional shape, composed of 136 filaments of single fiber fineness of 3.5 dtex, with a total fineness of 470 dtex, a tensile strength of 8.5 cN / dtex, and an elongation of 23.5%, and without twist, were prepared.

[0052] (Weaving) The above synthetic fiber filaments were used as warp and weft threads, and a water jet loom equipped with a full-width temple device was used to weave a plain fabric with a warp density of 50 threads / 2.54 cm and a weft density of 50 threads / 2.54 cm. The temple device for the loom includes a ring temple portion that grips both ears of the base fabric as shown in Fig. 1, and a full-width temple portion that grips the entire fabric with a fabric gripping bar. The full-width temple is arranged on the take-up side rather than the ring temple. The fabric gripping bar has both a left screw-shaped portion and a right screw-shaped portion, with a pitch and lead of the screw being 1.25 mm, and a central portion of the gripping bar where the left screw-shaped portion and the right screw-shaped portion are joined was used.

[0053] At that time, winding yarns and increasing yarns were used for both ears of the fabric. As the winding yarns, 22 detex nylon 66 monofilaments were used, and two were supplied to each ear from a planetary device. The increasing yarns used the same 22 dtex nylon 66 monofilaments as the winding yarns, and four were supplied to each ear from a bobbin. In weaving, the protrusion of the ears could be suppressed to a small extent.

[0054] (Scouring and Heat Setting) Next, the obtained fabric was scoured at 65°C with an open soaper type scouring machine, rinsed with hot water at 40°C, and dried at 120°C. Furthermore, using a pin tenter dryer, the width expansion rate was set so that the width would be the same as the width of the dried fabric, and the fabric was heat set at 160°C for 60 seconds under dimensional control with an overfeed rate of 0%. The characteristics of the obtained fabric are shown in Table 1. The obtained fabric had small ear flares and a uniform and good ear tightening state.

[0055] <Example 2> As the warp and weft threads, synthetic fiber filaments made of polyester, with 72 filaments per single fiber and a total fineness of 56 dtex, were used as warp and weft threads. A fabric was produced in the same manner as in Example 1, except that the warp density was changed to 170 threads / 2.54 cm and the weft density was changed to 130 threads / 2.54 cm.

[0056] In weaving, the protrusion of the ear part could be suppressed to a small level. The properties of the obtained fabric are shown in Table 1. The obtained fabric had a small ear flare and a uniform and good ear tightening state.

[0057] <Comparative Example 1> As a loom template device, an airbag fabric was produced in the same manner as in Example 1, except that only the full-width template part that grips the entire fabric with a fabric gripping bar as shown in Fig. 2 was used, and the fabric gripping bar had both a left screw-shaped part and a right screw-shaped part, and the one in which the left screw-shaped part and the right screw-shaped part were joined at the central part of the gripping bar was used. The properties of the obtained fabric are shown in Table 1. In weaving, the protrusion of the ear part could be suppressed to a small level, but the obtained fabric had a large ear flare and the ears lifted when the fabric was spread on the loom.

[0058] <Comparative Example 2> As a loom template device, an airbag fabric was produced in the same manner as in Example 1, except that only the ring template part was used without using the full-width template part that grips the entire fabric. In weaving, a large protrusion of the ear part occurred, ear splitting was likely to occur, and weaving was difficult. The obtained fabric had ear collapse, and the quality as a fabric deteriorated significantly.

[0059]

Table 1

Explanation of Signs

[0060] 1 Warp 2 Reed 3 Weft Nozzle 4 Weft 5 Weft Cutter 6 Ring Template Device 7 Full-Width Template Device 8 Fabric 9 Pushed-Out Fabric 10 Fabric Gripping Bar 11 Support Member 11a Mounting Portion 11b Edge 11c Engaged Portion 12 Pressing member 12a Pressing member body 12b Engaging portion 13 Temporal device support base 14 Left screw portion 15 Right screw portion 16 Warp density distribution of fabric in conventional manufacturing method 17 Warp density distribution of fabric in manufacturing method of the present invention WP1 First maximum value WP2 Second maximum value

Claims

Claim 1 A fabric made of synthetic fibers, having a cover factor of 2000 or more, and in at least one of the ear portions of the fabric, having a first maximum value WP1 of the warp density within a range of 2 to 7 mm from the fabric end, and having a second maximum value WP2 of the warp density within a range of 7 to 15 mm from the fabric end, and WP1 / Nw is 1.20 to 1.35 and WP2 / Nw is 1.1 to 1.2 with respect to the warp density Nw of the ground portion, a fabric characterized by this. Claim 2 The fabric according to claim 1, which is a fabric for an airbag. Claim 3 A manufacturing method for manufacturing the fabric according to claim 1 or 2, using a loom temple device for gripping the fabric during weaving, the loom temple device including a ring temple device for gripping both ears of the base fabric and a full-width temple device for gripping the entire fabric by a fabric gripping bar, the full-width temple device being disposed on the winding side rather than the ring temple device, and the fabric gripping bar having both a left threaded portion and a right threaded portion, a manufacturing method of the fabric.

Images