JP2008285766A - Coated fabric for air bag, air bag, and method for producing coated fabric for air bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coated fabric for an air bag, which has low air permeability and an impact-resistant bonded force on the operation of the air bag, required for a woven fabric for the air bags, and can prevent the leakage of air from seamed portions by the impact without needing a special device such as a sealant, and to provide the air bag. <P>SOLUTION: This coated fabric for the air bag has warps and wefts of synthetic fibers, satisfies the following requirements, and coats at least one side of the fabric with a resin. (1) 1.1≤Df/Dw≤2.0, wherein, Dw: the total fineness (dtex) of the warps, Df: the total fineness (dtex) of the wefts. (2) CF2/CF1≥1.05, wherein, CF1: the cover factor of the warps, CF1=(Dw×0.9)<SP>1/2</SP>×Nw, CF1: the cover factor of the wefts, CF2=(Df×0.9)<SP>1/2</SP>×Nf, Nw: the weave density of the warps (warps/2.54 cm), Nf: the weave density of the wefts (warps/2.54 cm). (3) EC1≥200N, EC2≥200N, wherein, EC1: the sliding resistance (N) in the warp direction by ASTM D6479-02, EC2: the sliding resistance (N) in the weft direction by ASTM D6479-02. (4) 0.80≤EC2/EC1≤1.20. (5) Ventilation volume of ≤0.1 cm<SP>3</SP>/cm<SP>2</SP>.min, when measured at a test differential pressure of 125 Pa on the basis of a Frazier form method defined by JIS L 1096:1999 8.27.1 A method. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an airbag which is one of automobile safety parts. The present invention also relates to a coated fabric for an air bag constituting the same and a method for producing the same.

  In recent years, with the improvement of traffic safety awareness, the effectiveness of various airbags has been recognized as a result of the development of various airbags in order to ensure the safety of passengers in the event of a car accident. It is out.

  The airbag is inflated and deployed in the vehicle in a very short time after the vehicle has collided, thereby receiving the occupant moving by the reaction of the collision and absorbing the impact to protect the occupant. In view of this action, it is required that the amount of ventilation of the fabric constituting the bag is small. Further, in order to keep the internal pressure of the bag at a certain level or higher when the airbag is inflated and deployed and catches the occupant, it is necessary to reduce air leakage from the sewing portion of the airbag as much as possible. In particular, in a side curtain airbag that protects the head at the time of a side collision or a rollover of an automobile, since the airbag is required to maintain a predetermined shape for a relatively long time when the automobile rolls over, there is a demand for preventing air leakage. large. Furthermore, the compactness at the time of storage is calculated | required from the design property in a vehicle, and the relationship with other components, Furthermore, the request | requirement of cost reduction is also increasing.

  Therefore, as a means for reducing the air flow rate on the fabric surface, a coated fabric in which a resin is applied to the fabric surface or a film is attached is proposed. For example, a fabric woven with synthetic fiber multifilaments of 500 denier or less is proposed. A coated cloth for coating a resin film is disclosed (for example, see Patent Document 1). This means is that a resin film is coated on a woven fabric of synthetic fiber multifilaments of 500 denier or less so that the slip resistance when the force is applied to the sewing portion is 8 to 20 mm. is there.

  However, although this means can prevent air leakage from the fabric surface, there is a problem in that it is difficult to maintain the necessary internal pressure because air leaks from the gap formed in the seam portion by the impact during the operation of the airbag.

  On the other hand, as means for preventing air leakage from the seam portion, means for heat-welding base fabrics constituting an airbag is also known (see, for example, Patent Document 2).

  According to this means, gas leakage from the outer peripheral portion of the bag body can be prevented by thermally welding a base fabric provided with a polyurethane resin, preferably a polycarbonate type polyurethane resin, on at least one side of the fabric.

  However, as mentioned in this publicly known example, thermal welding alone may not withstand the impact of airbag deployment, and in addition to thermal welding, it is necessary to reinforce by sewing. There was a drawback of increasing.

  As another means for preventing air leakage from the seam portion, there is also known an airbag means in which the joint portion of the base fabric is constituted by a joining means composed of sewing and adhesion with a sealant (see, for example, Patent Document 3). ).

  According to this means, the secrecy of the sewn portion can be increased by applying the sealing agent to the portion where the fabric is to be sewn and then laminating and crimping the fabric and sewing the seal portion.

  However, there are drawbacks in that there are many manufacturing precautions, such as applying a sealing agent at a predetermined position and sewing it accurately without detaching the portion where the sealing agent is applied. Moreover, compared with the joining by normal sewing, there was also a fault that the whole airbag is bulky and the storage property is inferior because the sealing agent is applied.

As described above, in the prior art, the airbag has a joining force that can withstand the impact when the airbag is activated, and can prevent air leakage from the seam portion due to the impact without special measures such as a sealing agent. Coated cloth has not been realized.
Japanese Patent Laid-Open No. 7-164988 (Claim 1) JP 2001-315610 A (Claim 1, paragraph 0036) JP 2004-122821 A (Claim 1)

  The object of the present invention is to solve the above-mentioned problems of the prior art, have low air permeability required for airbag fabrics, and have a joining force that can withstand the impact when the airbag is operated, and further, air from the seam portion caused by the impact. An object of the present invention is to provide a coated cloth for an airbag, an airbag, and a method for manufacturing the coated cloth for an airbag, which can prevent leakage without special measures such as a sealing agent.

That is, the present invention is a coated fabric for an air bag which is composed of a warp yarn and a weft yarn made of a synthetic fiber and satisfies the following requirements.
(1) 1.1 ≦ Df / Dw ≦ 2.0
here,
Dw: Total fineness of warp yarn (dtex),
Df: The total fineness (dtex) of the weft.
(2) CF2 / CF1 ≧ 1.05
here,
CF1: Cover factor of warp yarn,
CF1 = (Dw × 0.9) ^1/2 × Nw,
CF2: Weft cover factor,
CF2 = (Df × 0.9) ^1/2 × Nf,
Nw: Woven density of warp yarn (main / 2.54 cm),
Nf: Weft density of the weft yarn (main / 2.54 cm).
(3) EC1 ≧ 200N, EC2 ≧ 200N
here,
EC1: Vertical slip resistance (N) according to ASTM D6479-02,
EC2: Horizontal sliding resistance (N) according to ASTM D6479-02.
(4) 0.80 ≦ EC2 / EC1 ≦ 1.20
(5) JIS L 1096: 1999 8.27.1 The air flow rate when measured at a test differential pressure of 125 Pa based on the Frazier method defined by the A method is 0.1 cm ³ / cm ² · min or less.

  Moreover, this invention is an airbag characterized by sewing the coat cloth for airbags of this invention.

  The present invention also relates to a method for producing an airbag fabric according to the present invention, wherein the fabric is woven by adjusting the warp yarn tension to 50 to 230 cN / string in weaving. Is the method.

  According to the present invention, as will be described below, the problem that could not be solved by the conventional method, that is, the low air permeability required for the airbag fabric and the bonding strength to withstand the impact when the airbag is activated, Furthermore, it is possible to obtain a coated cloth for an airbag and an airbag that can prevent air leakage from the seam portion due to the impact without special measures such as a sealing agent.

  The coated fabric for airbag of the present invention is made of synthetic fiber. Examples of synthetic fiber materials that can be used include polyamide fibers, polyester fibers, aramid fibers, rayon fibers, polysulfone fibers, and ultrahigh molecular weight polyethylene fibers. Of these, polyamide fibers and polyester fibers excellent in mass productivity and economy are preferable.

  Examples of polyamide fibers include nylon 6, nylon 66, nylon 12, nylon 46, copolymer polyamide of nylon 6 and nylon 66, and copolymer obtained by copolymerizing nylon 6 with polyalkylene glycol, dicarboxylic acid, amine, and the like. Mention may be made of fibers made of polyamide or the like. Nylon 6 fiber and nylon 66 fiber are particularly excellent in impact resistance and are preferable.

  Examples of the polyester fiber include fibers made of polyethylene terephthalate, polybutylene terephthalate, and the like. It may be a fiber made of a copolymerized polyester obtained by copolymerizing polyethylene terephthalate or polybutylene terephthalate with an aliphatic dicarboxylic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid or adipic acid as an acid component.

  Synthetic fibers also have thermal stabilizers, antioxidants, light stabilizers, smoothing agents, antistatic agents, plasticizers, thickeners to improve productivity and properties in the spinning / drawing process and processing process. Additives such as additives, pigments, and flame retardants may be included.

  In addition to the round cross section, it is also preferable to use a flat cross section as the cross-sectional shape of the single fiber of the synthetic fiber. By using a flat cross-section fiber, the filling of the fiber when it is made into a woven fabric is promoted, the gap occupied between the single fibers in the woven fabric is reduced, and if the woven fabric structure is the same, a round cross-section yarn of the same fineness was used. The amount of ventilation can be suppressed more than the case. As for the shape of the flat cross section, when the cross section of the single fiber is approximated to an ellipse, the flatness defined by the ratio (D1 / D2) of the major axis (D1) to the minor axis (D2) is 1.5-4. It is preferable that there is, more preferably 2.0 to 3.5. Such a flat cross-sectional shape may be a geometrically true elliptical shape, for example, a rectangular shape, a rhombus shape, and a saddle shape, and may be a left-right symmetric shape or a left-right asymmetric shape. Moreover, the thing of the shape which combined these may be sufficient. Furthermore, with the above as a basic shape, there may be a protrusion, a dent, or a partially hollow portion.

  The warp yarn and the weft yarn used in the present invention are preferably synthetic fibers having a relatively low fineness of 1 dtex or more and 7 dtex or less as the single fiber fineness. This is because the synthetic fiber can be produced without special measures by setting it to 1 dtex or more, and the flexibility of the synthetic fiber is improved by setting it to 7 dtex or less. The fineness is more preferably 1.5 dtex or more and 4.0 dtex or less, and still more preferably 2.0 dtex or more and 3.0 dtex or less. When the single fiber fineness is within these more limited ranges, the space occupied between the single fibers in the fabric is reduced, and the fiber filling effect is further improved. By setting the single fiber fineness in the above-described low range, an effect of reducing the rigidity of the synthetic fiber can be obtained. In addition, by improving the filling of single fibers, the surface area of the fabric is reduced and the smoothness is increased, so that it can be applied uniformly when applying the resin, and the surface of the fabric can be covered with a small amount of resin used. This is preferable from the viewpoint of weight reduction. Furthermore, by using weaving conditions under certain conditions such as weaving in a state where the warp yarn tension is increased as will be described later, the stability of the fabric structure between the warp yarn and the weft yarn is dramatically improved, The eye misalignment can be remarkably improved.

  The total fineness of the warp yarn and the weft yarn is preferably 100 to 700 dtex. By setting it to 100 dtex or more, the strength of the fabric can be maintained. Moreover, the compactness at the time of accommodation can be maintained by setting it as 700 dtex or less. In particular, the warp yarn is more preferably 200 to 400 dtex, and further preferably 300 to 400 dtex. The total fineness of the weft yarn is more preferably 300 to 700 dtex, and further preferably 400 to 500 dtex.

  Furthermore, it is important that the total fineness Dw (dtex) of the warp yarn and the total fineness Df (dtex) of the weft yarn satisfy the relationship 1.1 ≦ Df / Dw ≦ 2.0. Thus, by making the total fineness of the weft yarn larger than the total fineness in the warp direction, it becomes easier to achieve the relationship CF2 / CF1 ≧ 1.05 of the warp yarn and weft cover factor described later, It is possible to improve both the sliding resistance in the vertical and horizontal directions in a well-balanced manner.

  The tensile strength of the yarn constituting the coated fabric for airbags of the present invention is 8.0 for both warp and weft yarns in order to satisfy the mechanical properties required for airbag fabrics and the productivity of synthetic fibers. -9.0 cN / dtex is preferable, More preferably, it is 8.3-8.7 cN / dtex.

  The weave density of the coated fabric for airbags of the present invention may be set as appropriate so as to satisfy the relationship of the cover factor described later, where Nw is the warp yarn weave density, Nf is the weft yarn density, and Nf / Nw. ≧ 0.90 is preferable, and Nf / Nw ≧ 1.00 is more preferable.

In the present invention, the cover factor (CF1) of the warp yarn of the woven fabric and the cover factor (CF2) of the weft yarn are defined as follows.
CF1 = (Dw × 0.9) ^1/2 × Nw
CF2 = (Df × 0.9) ^1/2 × Nf
here,
Dw: Total fineness of warp yarn (dtex),
Df: the total fineness (dtex) of the weft
Nw: Woven density of warp yarn (main / 2.54 cm),
Nf: Weft density of the weft yarn (main / 2.54 cm).

  The cover factor of the warp yarn and the weft yarn of the woven fabric is preferably 700 to 1250. By adjusting the cover factor within this range, it is possible to achieve both compact storage properties and sliding resistance required as a coated fabric for an airbag. If any one of the cover factors is smaller than 700, the compact storability is improved, but the sliding resistance is lowered, which is not preferable. If any of the cover factors is larger than 1250, the slip resistance is increased, but the compact storage property is lowered, which is not preferable.

  In the coated fabric for an air bag of the present invention, it is essential that the cover factor CF1 of the warp yarn and the cover factor CF2 of the weft yarn satisfy the relationship of CF2 / CF1 ≧ 1.05, and preferably CF2 / CF1 ≧ 1.10. In order to improve the slip resistance in the warp direction and the weft direction of the fabric in a balanced manner compared to a woven fabric with a symmetrical structure where the cover factor of the warp yarn fabric and the cover factor of the weft yarn fabric are equal. Is essential.

  In order to improve the balance between the sliding resistance in the warp direction and the weft direction, the present inventors have intensively studied the relationship between the warp and weft cover factors of the fabric and the slip resistance in each direction. As the method, the cover factor of the warp yarn of the woven fabric was fixed, the cover factor of the weft yarn was changed, and the sliding resistance force according to ASTM D6479-02 was measured. As shown in Table 1, the weft of the weft yarn of the woven fabric was measured. Surprisingly, increasing the cover factor relative to the cover factor of the warp of the woven fabric not only improves the sliding resistance of the fabric in the horizontal direction, but also improves the sliding resistance in the vertical direction. It was found that the resistance can be improved in a well-balanced manner. Note that the sliding resistance force in the warp direction is a value when the pin is inserted in parallel with the weft thread and the weft thread is moved along the longitudinal direction of the warp thread as described in ASTM D6479-02. The maximum load was measured, and the sliding resistance in the horizontal direction was measured by measuring the maximum load when a pin was inserted in parallel with the warp and the warp was moved along the longitudinal direction of the warp. Is.

  It is considered that the contact state at the intersection of the warp yarn and the weft yarn has an effect on the improvement of the sliding resistance. That is, the larger the contact area at the crossing point, the greater the frictional resistance between the warp and the weft and the less likely the movement of the yarn during the sliding resistance measurement. In order to increase the contact area between the warp yarn and the weft yarn at the intersection, it can be realized by increasing the total fineness of the synthetic fiber yarn or increasing the weave density. In the former case, the contact area is increased by increasing the surface area when the cross section of the synthetic fiber yarn is regarded as substantially elliptical. In the latter case, the contact area is increased by increasing the number of contact between the warp yarn and the weft yarn.

  By the way, the airbag fabric generally has a so-called warp bent structure in which the warp yarn has a higher crimp rate due to restraint in the weave structure than the weft yarn. This is because, during weaving, the weft yarn is driven linearly with a greater tension than the warp yarn, and the warp yarn is woven while creating a bent structure by opening movement.

  Considering this warp bending structure, when the cover factor CF1 of the warp yarn of the woven fabric is made larger than the cover factor CF2 of the weft yarn, the tension of the weft yarn cannot contribute much to the formation of the warp bending structure. The bending structure of both the yarn and the weft does not change greatly, and the effect of increasing the contact area cannot be obtained. On the other hand, when the cover factor CF2 of the weft of the woven fabric is made larger than the cover factor CF1 of the warp yarn, the warp bend structure can be promoted both when the total fineness of the weft yarn is increased and when the weave density is increased. . Thus, since the contact area between the warp yarn and the weft yarn can be more efficiently improved by the promotion of the warp bending structure, it is considered that the sliding resistance in the horizontal direction and the sliding resistance in the vertical direction can be improved at the same time. Accordingly, it has been found that increasing the cover factor CF2 of the weft of the woven fabric relative to the cover factor CF1 of the warp yarn is the point of improving both the sliding resistance in the warp direction and the weft direction.

  The coated fabric for airbag in the present invention requires that at least one surface of the fiber fabric is coated with a resin. By covering at least one surface with a resin, it is possible to provide air barrier properties and further protect the fabric from high-temperature gas generated from the inflator.

  Such a resin is preferably a resin having heat resistance, cold resistance, and flame retardancy, and examples thereof include silicone resins, polyamide resins, polyurethane resins, and fluororesins. Among these, silicone resins are particularly preferable from the viewpoints of heat resistance and air barrier properties. For such silicone resins, dimethyl silicone resins, methyl vinyl silicone resins, methyl phenyl silicone resins, and fluoro silicone resins are used.

  Further, the resin covering the fiber fabric preferably contains a flame retardant compound. Such flame retardant compounds include halogen compounds containing bromine, chlorine, etc., in particular, halogenated cycloalkanes, platinum compounds, antimony oxides, copper oxides, titanium oxides, phosphorus compounds, thiourea compounds, carbon, cerium, silicon oxide, etc. Among these, halogen compounds, platinum compounds, copper oxide, titanium oxide, and carbon are more preferable.

The adhesion amount of the resin for coating the fabric is preferably 5 to 45 g / m ² , more preferably 10 to 30 g / m ² . By setting the adhesion amount within this range, it is possible to achieve both compact storage properties, low air permeability, and heat resistance of the coated fabric for airbag. By making the adhesion amount of the resin 5 g / m ² or more, the fabric surface can be covered uniformly, and the effect of improving the low air permeability and improving the heat resistance can be obtained. Moreover, by setting it as 45 g / m < ² > or less, it can prevent that storage property is inhibited and can also suppress cost.

  In the coated fabric for an air bag of the present invention, it is important that the sliding resistance EC1 in the vertical direction and the sliding resistance EC2 in the horizontal direction according to ASTM D6479-02 are both 200 N or more, preferably both are 250 N or more, more preferably Are both over 300N. By doing so, the occurrence of misalignment of the sewing portion when the airbag is inflated and deployed to restrain the occupant can be suppressed as much as possible, and the bag internal pressure can be maintained. If it is less than 200 N, the stitches will be misaligned and the internal pressure of the airbag cannot be maintained.

In the coated fabric for an airbag of the present invention, it is important that the sliding resistance (EC1) in the vertical direction and the sliding resistance (EC2) in the horizontal direction have the following relationship.
0.85 ≦ EC2 / EC1 ≦ 1.15
By doing so, the misalignment of the sewing portion when the airbag is inflated and deployed to restrain the occupant can be suppressed as much as possible, and the internal pressure of the airbag can be maintained. Since the airbag is originally deployed isotropically vertically and horizontally, if EC1 and EC2 do not satisfy the above relationship, misalignment of the sewing portion will occur in the direction of low sliding resistance, and the internal pressure of the airbag cannot be maintained. .

The air bag coated fabric of the present invention has an air flow rate of 0.1 cm ³ / measured at a test differential pressure of 125 Pa based on the Frazier method defined by JIS L 1096: 1999 8.27.1 A method. It is also necessary to be cm ² · min or less. By adjusting the ventilation amount to the above range, the inflation gas emitted from the inflator at the time of collision can be used effectively without leakage, and the occupant can be reliably received.

  Furthermore, the coated fabric for an airbag of the present invention is JIS K 6404-3. The tensile strength based on the strip method specified by the test method B method is preferably 400 N / cm or more, more preferably 500 N / cm or more, and further preferably 550 N / cm or more. By setting it to 400 N / cm or more, when the airbag is inflated and deployed to restrain the occupant, the airbag can be prevented from being damaged due to the breakage of the fabric.

  Next, a method for producing the coated fabric for an airbag according to the present invention will be described.

  The coated fabric for an airbag of the present invention is woven by using synthetic fiber yarns for warp yarns and weft yarns, and setting the cover factor of the fabric weft yarns to be larger than the cover factor of the warp yarns of the fabric.

  First, warp the warp yarn of the above-mentioned material and the total fineness and apply it to the loom, and prepare the weft yarn in the same manner. As such a loom, for example, a water jet room, an air jet room, a rapier room, and the like can be used. In particular, in order to increase productivity, it is preferable to use a water jet loom which is relatively easy to weave at high speed.

  As a method for producing the airbag fabric of the present invention, it is preferable to adjust the warp yarn tension to 75 to 230 cN / line in weaving, and more preferably 100 to 200 cN / line. By adjusting the warp yarn tension within such a range, it is possible to reduce the gaps between single fibers in the yarn bundle of multifilament yarns constituting the woven fabric. Moreover, the warp yarn to which the tension is applied pushes and bends the weft yarn after driving the weft yarn, so that an effect of increasing the tissue restraining force of the fabric in the weft direction can be obtained. Thereby, the anti-missing property of the fabric is improved, and air leakage due to misalignment of the sewing portion when forming a bag as an airbag can be suppressed, which is preferable. When the warp yarn tension is less than 75 cN / line, the contact area between the warp yarn and the weft yarn in the woven fabric cannot be increased, and the sliding resistance is not improved. Further, since the effect of reducing the gap between the single fibers is small, it is necessary to increase the amount of the resin in order to compensate for the low air permeability, which is not preferable from the viewpoint of storage. On the other hand, if it exceeds 230 cN / string, the warp yarn becomes fluffy and the weaving property deteriorates.

  Specific methods for adjusting the warp yarn tension within the above range include a method of adjusting the weft yarn feeding speed in addition to adjusting the warp yarn feed speed of the loom. Whether warp yarn tension within the above range is actually generated during weaving is measured, for example, by measuring the tension applied per warp yarn between the warp beam and the back roller with a tension measuring instrument while the loom is running. Can be confirmed.

  It is preferable to use a bar temple as the loom temple. When the bar temple is used, it can be beaten while gripping the entire front of the weave, so that the gap between the synthetic fiber filaments can be reduced, and as a result, the low air permeability and anti-displacement are improved. .

  Following the weaving process, if necessary, processing such as scouring and heat setting is performed.

  In the coated fabric for an airbag of the present invention, a resin is applied to at least one surface of the woven fabric.

  The viscosity of the resin liquid is preferably 5 to 20 Pa · s (5,000 to 20,000 cP) for stable application with a uniform application amount. Here, the viscosity of the resin liquid is measured with a B-type viscometer based on JIS Z 8803. By setting the viscosity to 5 Pa · s (5,000 cP) or more, it is suitable for knife coating described later. Moreover, by setting it as 20 Pa * s (20,000 cP) or less, it can coat with a low application quantity and is preferable on storage compactness. The viscosity of the resin liquid may be adjusted by diluting with a solvent, but using a solvent-free type resin that has been adjusted to a viscosity within the above range from the beginning is a viewpoint of workability and reduction of environmental load. To preferred.

  As a resin coating method, the knife coating method is preferable from the viewpoint of reducing the coating amount of the resin and stable coating. The knife coating method includes a knife over roll method, a knife over belt method, and a floating knife method. Of these, the floating knife method is more preferably used from the viewpoints of reducing the amount of resin applied and resin permeability to the fabric.

  The airbag according to the present invention is formed by sewing the coated fabric for an airbag according to the present invention into a bag shape, and normally operates by attaching an accessory such as an inflator.

  The airbag of the present invention is excellent in occupant restraint because it is formed using the coated fabric for airbags of the present invention that has excellent storability and is excellent in low breathability and anti-missing property.

[Measuring method]
(1) Fabric thickness According to JIS L 1096: 1999 8.5, using a thickness measuring machine at 5 different points of the sample, after waiting for 10 seconds under 23.5 kPa under pressure to stabilize the thickness The thickness was measured and the average value was calculated.

(2) Weave density of warp and weft yarns Measured based on JIS L 1096: 1999 8.6.1.
The sample was placed on a flat table, and the number of warp yarns and weft yarns in a 2.54 cm section was counted at five different locations, excluding unnatural wrinkles and tension, and the average value was calculated.

(3) Basis weight In accordance with JIS L 1096: 1999 8.4.2, three test pieces of 20 cm × 20 cm were sampled, each mass (g) was weighed, and the average value was the mass per 1 m ² (g / g m ² ).

(4) Amount of coating A blank sample was prepared under the same conditions except that no resin was applied. According to the above (3), the basis weight of the blank sample was measured, and the difference between the basis weight of the coated fabric and the basis weight of the blank sample was determined as the coating amount.

(5) Tensile strength JIS K 6404-3 6. In accordance with test method B (strip method), for each of the vertical and horizontal directions, five test pieces were collected, the yarn was removed from both sides of the width to a width of 30 mm, and a constant speed tension type testing machine, The test piece was pulled at a grip interval of 150 mm and a tensile speed of 200 mm / min, and the maximum load until cutting was measured, and the average value was calculated for each of the vertical and horizontal directions.

(6) Elongation at break JIS K 6404-3 In accordance with test method B (strip method), for each of the vertical direction and the horizontal direction, five test pieces are sampled, the thread is removed from both sides of the width to a width of 30 mm, and 100 mm intervals are provided at the center of these test pieces. With a marked line, with a constant-speed tension type testing machine, pull until the specimen is cut at a grip interval of 150 mm and a pulling speed of 200 mm / min, read the distance between the marked lines when reaching the cutting, The breaking elongation was calculated, and the average value was calculated for each of the vertical and horizontal directions.
E = [(L-100) / 100] × 100
Where E: elongation at break (%),
L: Distance (mm) between marked lines at the time of cutting.

(7) Tear strength JIS K 6404-4 According to test method B (single tongue method), test specimens with a long side of 200 mm and a short side of 76 mm were taken on the vertical and horizontal sides, respectively, and 5 specimens were collected respectively, and the test piece was perpendicular to the center of the short side. A 75 mm incision was made, and the specimen was torn with a constant speed tension type tester at a grip interval of 75 mm and a tensile speed of 200 mm / min until the specimen was pulled, and the tear load at that time was measured. From the obtained chart recording line of the tearing load, three points were selected from the maximum points excluding the first peak in descending order, and the average value was taken. Finally, an average value was calculated for each of the vertical and horizontal directions.

(8) Aeration rate Measured according to JIS L 1096: 1999 8.27.1 Method A (Fragile type method). Test pieces of about 20 cm × 20 cm were collected from five different locations of the samples, and the test pieces were attached to one end (intake side) of the cylinder using a Frazier type tester. After attaching the test piece, the suction fan was adjusted so that the inclination type barometer showed a pressure of 125 Pa by an adjusting resistor, and from the pressure indicated by the vertical type barometer and the type of air hole used, The amount of air passing through the test piece was obtained from a table attached to the test machine, and the average value for the five test pieces was calculated.

(9) Packability Measured according to ASTM D-6478-02.

(10) Sliding resistance force Measured according to ASTM D6479-02.

(11) Warp Yarn Tension Using Check Master (registered trademark) (Type: CM-200FR) manufactured by Kanai Koki Co., Ltd., and adding per warp yarn between the warp beam and the back roller during operation of the loom. Tension was measured.

(12) Resin viscosity Measured with a B-type viscometer based on JIS Z8803.

(13) Comprehensive Evaluation Criteria In Table 2 below, the packability obtained by the above measurement method and the sliding resistance value are set to 2000 cm ³ or less and 300 N or more, respectively, and both values are satisfied. , “◯”, the case where one of the values was satisfied was evaluated as “Δ”, and the case where both values were not satisfied was evaluated as “×”.

[Example 1]
(Vertical yarn)
Synthetic fiber made of nylon 6,6, with a circular cross-section, single fiber fineness 2.6 dtex, filament count 136, total fineness 350 dtex, untwisted, strength 8.5 cN / dtex, elongation 23.5% Multifilament was used as warp yarn.

(Horizontal thread)
Synthetic fiber made of nylon 6,6, having a circular cross-sectional shape, single fiber fineness of 3.5 dtex, filament count of 136, total fineness of 470 dtex, no twist, strength of 8.6 cN / dtex, elongation of 23.4% Multifilament was used as the weft.

(Weaving process)
Using the warp yarn and the weft yarn, a woven fabric having a warp yarn weaving density of 52 yarns / 2.54 cm and a weft yarn weaving density of 52 yarns / 2.54 cm was woven in a water jet loom. At that time, a bar temple was installed between the beating portion and the friction roller to grip the fabric, the warp yarn tension was adjusted to 147 cN / piece, and the loom rotation speed was 500 rpm.

(Heat setting process)
The fabric was then subjected to heat setting for 1 minute at 160 ° C. using a pin tenter dryer under the dimensional regulation of a width insertion rate of 0% and an overfeed rate of 0%.

(Coating process)
A solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is applied to the woven fabric subjected to the heat setting process, and the woven fabric and the slab knives with a floating knife coater using a slat knives. The coating pressure was maintained at 9 N / cm and the coating amount was 20 g / m ² , followed by vulcanization treatment at 190 ° C. for 1 minute to obtain a coated fabric for airbag.

  The coated fabric for airbags is non-breathable, has a well-balanced sliding resistance in the vertical and horizontal directions, and is excellent in compactness when stored, satisfying the target value.

[Example 2]
(Vertical yarn)
A warp yarn similar to that used in Example 1 was used.

(Horizontal thread)
A thread similar to that used in Example 1 was used.

(Weaving process)
Using the warp and weft yarns, a woven fabric having a warp yarn weaving density of 52 yarns / 2.54 cm and a weft yarn weaving density of 50 yarns / 2.54 cm was woven in the same manner as in Example 1.

(Heat setting process)
The above woven fabric was subjected to the same heat setting as in Example 1.

(Coating process)
A solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is applied to the woven fabric subjected to the heat setting process in the same manner as in Example 1 so that the resin adhesion amount becomes 20 g / m ^2. Coating and vulcanization treatment were performed to obtain a coated fabric for an airbag.

  The coated fabric for airbags is non-breathable, has a well-balanced sliding resistance in the vertical and horizontal directions, and is excellent in compactness when stored, satisfying the target value.

[Example 3]
(Vertical yarn)
A warp yarn similar to that used in Example 1 was used.

(Horizontal thread)
A thread similar to that used in Example 1 was used.

(Weaving process)
Using the warp yarn and the weft yarn, a woven fabric having a warp yarn weaving density of 55 yarns / 2.54 cm and a weft yarn weaving density of 59.5 yarns / 2.54 cm was woven in the same manner as in Example 1.

(Heat setting process)
The above woven fabric was subjected to the same heat setting as in Example 1.

(Coating process)
A solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is applied to the woven fabric subjected to the heat setting process, and the woven fabric and the slab knives with a floating knife coater using a slat knives. The coating pressure was maintained at 11 N / cm and the coating amount was 20 g / m ² , followed by vulcanization treatment at 190 ° C. for 1 minute to obtain a coated fabric for an airbag.

  The coated fabric for airbags is non-breathable, has a well-balanced sliding resistance in the vertical and horizontal directions, and is excellent in compactness when stored, satisfying the target value.

[Example 4]
(Vertical yarn)
A warp yarn similar to that used in Example 1 was used.

(Horizontal thread)
Synthetic fiber made of nylon 6,6, with a circular cross-sectional shape, single fiber fineness 4.3dtex, filament count 136, total fineness 585dtex, no twist, strength 8.2cN / dtex, elongation 24.0% Multifilament was used as the weft.

(Weaving process)
Using the warp and weft yarns, a woven fabric having a warp yarn weaving density of 52 yarns / 2.54 cm and a weft yarn weaving density of 50 yarns / 2.54 cm was woven in the same manner as in Example 1.

(Heat setting process)
The above woven fabric was subjected to the same heat setting as in Example 1.

(Coating process)
A solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is applied to the woven fabric subjected to the heat setting process, and the woven fabric and the slab knives with a floating knife coater using a slat knives. The coating pressure was maintained at 11 N / cm and the coating amount was 20 g / m ² , followed by vulcanization treatment at 190 ° C. for 1 minute to obtain a coated fabric for an airbag.

  The coated fabric for airbags is non-breathable, has a well-balanced sliding resistance in the vertical and horizontal directions, and is excellent in compactness when stored, satisfying the target value.

[Comparative Example 1]
(Vertical yarn)
A warp yarn similar to that used as the weft yarn in Example 1 was used.

(Horizontal thread)
The same thread used as the warp thread in Example 1 was used as the weft thread.

(Weaving process)
A woven fabric having a warp yarn weaving density of 50.5 yarns / 2.54 cm and a weft yarn weaving density of 54 yarns / 2.54 cm was woven using the warp yarn and the weft yarn in the same manner as in Example 1.

(Heat setting process)
The above woven fabric was subjected to the same heat setting as in Example 1.

(Coating process)
For the airbag that has been subjected to the heat setting process, a solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is coated and vulcanized in the same manner as in Example 1. A coated fabric was obtained.

  This coated fabric for airbags is non-breathable and has no problem with compactness when stored, but the sliding resistance in the vertical and horizontal directions is poorly balanced.

[Comparative Example 2]
(Vertical / Horizontal)
The same warp yarn and weft yarn were used as the warp yarn in Example 1.

(Weaving process)
Weaving a woven fabric having a warp yarn weaving density of 52.5 yarns / 2.54 cm and a weft yarn weaving density of 53.5 yarns / 2.54 cm using the warp yarn and weft yarn in the same manner as in Example 1. did.

(Heat setting process)
The above woven fabric was subjected to the same heat setting as in Example 1.

(Coating process)
For the airbag that has been subjected to the heat setting process, a solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is coated and vulcanized in the same manner as in Example 1. A coated fabric was obtained.

  This coated fabric for airbags is non-breathable and has no problem with compactness when stored, but the sliding resistance in the vertical and horizontal directions is poorly balanced.

[Comparative Example 3]
(Vertical yarn)
A warp yarn similar to that used in Example 1 was used.

(Horizontal thread)
Synthetic fiber made of nylon 6,6, having a circular cross-sectional shape, single fiber fineness of 6.9 dtex, number of filaments 136, total fineness of 940 dtex, no twist, strength 8.5 cN / dtex, elongation 22.5% Multifilament was used as the weft.

(Weaving process)
Using the warp yarn and the weft yarn, a woven fabric having a warp yarn weaving density of 52 yarns / 2.54 cm and a weft yarn weaving density of 37 yarns / 2.54 cm was woven in the same manner as in Example 1.

(Heat setting process)
The above woven fabric was subjected to the same heat setting as in Example 1.

(Coating process)
A solvent-free methyl vinyl silicone resin liquid having a viscosity of 12 Pa · s (12,000 cP) is applied to the woven fabric subjected to the heat setting process, and the woven fabric and the scallop knife are used with a floating knife coater using a slat knive. The coating pressure was maintained at 11 N / cm and the coating amount was 20 g / m ² , followed by vulcanization treatment at 190 ° C. for 1 minute to obtain a coated fabric for an airbag.

  Although this air-coated fabric has no problem with air permeability, the compactness at the time of storage is poor, and the balance of sliding resistance in the vertical direction and the horizontal direction is also poor.

  The characteristics of the airbag coated fabrics of the examples and comparative examples are shown in the table.

  The airbag of the present invention can be used for a driver's seat, a passenger seat, a rear seat, a side airbag, and the like. In particular, it is suitable for use as a side curtain airbag in which an airbag is required to maintain a predetermined shape for a relatively long time in order to protect the head in a side collision or a rollover of an automobile.

Claims (8)

A coated fabric for an airbag comprising a warp yarn and a weft yarn made of a synthetic fiber, satisfying the following requirements, and coated with a resin on at least one surface.
(1) 1.1 ≦ Df / Dw ≦ 2.0
here,
Dw: Total fineness of warp yarn (dtex),
Df: The total fineness (dtex) of the weft.
(2) CF2 / CF1 ≧ 1.05
here,
CF1: Cover factor of warp yarn,
CF1 = (Dw × 0.9) ^1/2 × Nw,
CF2: Weft cover factor,
CF2 = (Df × 0.9) ^1/2 × Nf,
Nw: Woven density of warp yarn (main / 2.54 cm),
Nf: Weft density of the weft yarn (main / 2.54 cm).
(3) EC1 ≧ 200N, EC2 ≧ 200N
here,
EC1: Vertical slip resistance (N) according to ASTM D6479-02,
EC2: Horizontal sliding resistance (N) according to ASTM D6479-02.
(4) 0.80 ≦ EC2 / EC1 ≦ 1.20
(5) JIS L 1096: 1999 8.27.1 The air flow rate when measured at a test differential pressure of 125 Pa based on the Frazier method defined by the A method is 0.1 cm ³ / cm ² · sec or less. The coated fabric for an air bag according to claim 1, wherein the fineness of the single fibers constituting the warp yarn and the weft yarn is 1 to 7 dtex, respectively. The coated fabric for an airbag according to claim 1 or 2, wherein the total fineness of the warp yarn and the weft yarn is 100 to 700 dtex. The cover fabric for airbags according to any one of claims 1 to 3, wherein a cover factor CF1 of warp yarn and a cover factor CF2 of weft yarn are both 700 to 1250. Furthermore, the coated fabric for airbags in any one of Claims 1-4 which satisfy | fills CF2 / CF1> = 1.10. An airbag formed by sewing the coated cloth for an airbag according to any one of claims 1 to 5. A method for producing a coated fabric for an airbag according to claim 1, wherein the weaving is carried out by adjusting the warp yarn tension to 50 to 230 cN / piece in weaving. The method for producing a coated fabric for an air bag according to claim 7, wherein a bar temple is used as the temple during weaving.