Airbag pads

Abstract

According to the present invention, there is provided a cushion fabric for an airbag that has excellent storage properties and excellent cut resistance when the airbag is deployed, and is particularly suitable for a curtain airbag. The cushion fabric for an airbag is a fabric, and the fabric satisfies the following formula: P x = E / (T x × F x ) × 1000, P y = E / (T y × F y ) × 1000, where E is the kinetic energy of the block and the tool, in J, T x is the average value of the tearing lengths in the warp direction, in mm, F x is the fineness of the warp yarns constituting the fabric, in dtex, T y is the average value of the tearing lengths in the weft direction, in mm, F y is the fineness of the weft yarns constituting the fabric, in dtex. At least one of the dynamic tear characteristics P x and P y is 0.8 or more.

Description

Technical Field

[0001] The present invention relates to a mat cloth attached to a main body cloth of an air bag which is one of safety devices for vehicles such as automobiles, and more particularly to a mat cloth suitable for being attached to a main body cloth of a curtain air bag. Background Art

[0002] In recent years, the rate of vehicle airbags has been increasing from the perspective of improving the safety of passengers in vehicles such as automobiles. Conventional automobile airbags are composed of sensors for detecting collisions, gas generators (inflators), and buffers. When the sensor detects a collision, the inflator operates, and the buffer expands (deploys) instantly under the action of the generated gas, thereby protecting the passengers from impact.

[0003] As such automobile airbags, in addition to driver airbags and passenger airbags that are installed in front of the driver's seat and the front passenger seat and mainly protect the occupants from the impact caused by the frontal collision of the vehicle, various airbags corresponding to the type of collision and the position of the occupants have been developed, such as side airbags that mainly protect the occupants from the impact caused by the side collision of the vehicle and knee airbags that protect the legs of the occupants.

[0004] The curtain airbag, which mainly protects passengers from the impact caused by the side collision, is designed to be stored in the area from the front pillar side to the rear pillar side along the roof rail of the car, for example, and expand and deploy in a curtain shape along the side window glass when a collision is detected. In the case of the curtain airbag, it is necessary to instantly enter between the passenger's head and the glass to protect the head when deploying. However, in order to suppress not only the primary impact (first impact) caused by the collision, but also the impact caused by the rollover of the vehicle body or prevent the passenger from being thrown out of the vehicle, the internal pressure of the buffer is required not to be greatly reduced, and the buffer shape and deployment action are required to have a protection range that covers the side window glass.

[0005] Such a curtain airbag is folded into a roll or bellows shape when stored, and then fixed by a base cloth or a belt. In order to meet the above-mentioned required characteristics and keep the interior space of the vehicle large, excellent storage performance (compactness) is extremely important for the curtain airbag.

[0006] When the curtain airbag is deployed, when the airbag is deployed in one direction at a relatively fast speed, there is a problem that the surface of the airbag main body cloth is cut in a tearing pattern in one direction due to the interference between the buffer surface and the side window glass, obstacles inside and outside the vehicle body, etc. If such a cut occurs, the internal pressure retention performance of the buffer is reduced, and the reaction force characteristics of the airbag are significantly reduced, which may impair the impact absorption performance required of the airbag.

[0007] Patent document 1 (Korea Patent No. 10-0792423) describes a method for obtaining a curtain airbag having the following functions: by installing a protective member on the outer side of the buffer of the curtain airbag, the protective member is prevented from directly contacting the protective buffer with door glass fragments, sharp fragments of the vehicle body and interior trim when the protective buffer is deployed, thereby protecting the buffer and protecting the head of the occupant during a side collision. However, in this method, both the main body cloth of the curtain airbag and the protective member need to be fixed to the vehicle body, so there are problems such as poor storage performance of the airbag as a whole, poor efficiency in manufacturing the airbag and installing it on the vehicle body.

[0008] Patent document 2 (Japanese Patent Publication No. 2004-522003) describes a method for obtaining a cloth suitable for use in a curtain airbag, wherein at least one covering, film, cloth or layer is arranged on the outer surface, so that the cloth has excellent wear resistance, damage resistance and their combined characteristics. However, the most important dynamic tear mode of the cuts generated when the curtain airbag is deployed in one direction at a faster speed has not been studied. In addition, in the method of arranging a covering or film such as a polyurethane elastomer on the surface of the airbag main body cloth, the hardness of the buffer main body cloth is increased, which sometimes leads to a decrease in the storage property and the deployment speed. In addition, Patent document 2 shows a form of arranging a cloth layer close to the buffer main body cloth, but no research has been conducted on the physical properties and structure of the cloth layer.

[0009] Patent document 3 (Japanese Patent Publication No. 2006-62590) describes the following method: a covering material is applied to the surface of the buffer, and the material is designed to have a penetration strength of 5N or more when penetrated by a pressing blade, as measured by a constant-speed elongation rupture tester described in Japanese Industrial Standard JIS L-1096 (8.16.2B method), thereby protecting the airbag from the influence of cuts and absorbing the impact on the occupant without damage or breakage. In one form of this method, a fabric composed of high-strength fibers such as aromatic polyamide is sewn to the airbag body base fabric to increase the penetration strength when penetrated by a pressing blade. However, the damage mode based on the pressing blade measured by a constant-speed elongation rupture tester described in Japanese Industrial Standard JIS L-1096 (8.16.2B method) is a relatively low-speed puncture mode, and the most important dynamic tearing mode in the cuts generated when the curtain airbag is deployed at a relatively fast speed in one direction has not been studied. In addition, in the method of applying the cut-resistant material, the hardness of the shock absorber body cloth increases, which may cause the storage property to deteriorate. In any form, there is no description of the coexistence of cut-resistant and storage property of the curtain airbag.

[0010] Prior art literature

[0011] Patent Literature

[0012] Patent Document 1: Korean Patent No. 10-0792423

[0013] Patent Document 2: Japanese Patent Application No. 2004-522003

[0014] Patent Document 3: Japanese Patent Application Publication No. 2006-62590 Summary of the invention

[0015] Problem that the invention aims to solve

[0016] The present invention has been made in view of the above-mentioned problems of the prior art, and provides an airbag mat having excellent storage properties and excellent cut resistance during airbag deployment.

[0017] Solutions for solving problems

[0018] Examples of embodiments of the present invention are described in the following technical aspects [1] to

[13] .

[0019] [1] An airbag padding fabric attached to a main body fabric of an airbag, wherein the airbag padding fabric is a woven fabric, and in the woven fabric, a dynamic tearing property P expressed by the following formula: x and P y At least one of the following is 0.8 or more:

[0020] P x =E / (T x ×F x )×1000

[0021] P y =E / (T y ×F y )×1000

[0022] Where E is the kinetic energy of the block and the cutter in the dynamic tear test of performance level 3 as described in Japanese Industrial Standard JIS T 8050, in J, T x It is the average tear length in the warp direction in the dynamic tear test of performance level 3 described in Japanese Industrial Standard JIS T 8050, the unit is mm, F x It is the warp yarn fineness of the fabric, measured in dtex, T y It is the average tear length in the weft direction in the dynamic tear test of performance level 3 described in Japanese Industrial Standard JIS T 8050, in mm, F y It is the fineness of the weft yarn that makes up the fabric, measured in dtex.

[0023] [2] The airbag pad according to claim 1, wherein the T of the airbag pad is x With T y The ratio of x and T y The smaller of the two divided by the larger one is less than 0.94.

[0024] [3] The airbag mat according to claim 1 or 2, wherein in the airbag mat, for the warp cover factor CF represented by the following formula: x and the latitudinal cover factor CF y The ratio of CF x and CF y The smaller of the two divided by the larger of the two is greater than 0.30 and less than 0.80:

[0025]

[0026] Where D x is the number of warp yarns per 2.54 cm, i.e. the warp yarn density, F x It is the fineness of the warp yarns that make up the fabric, measured in dtex, D y is the number of weft yarns per 2.54 cm, i.e. the weft yarn density, F y It is the fineness of the weft yarn that makes up the fabric, measured in dtex.

[0027] [4] The airbag mat according to any one of claims 1 to 3, wherein the airbag mat has a warp cover factor CF x and the latitudinal cover factor CF y The sum of is greater than 1500 and less than 2200.

[0028] [5] The airbag mat according to any one of claims 1 to 4, wherein the total fineness of the warp yarn and the weft yarn constituting the airbag mat is 210 dtex or more and 550 dtex or less.

[0029] [6] The airbag mat according to any one of claims 1 to 5, wherein the slip resistance of the airbag mat is 10 N or more and 400 N or less in both the warp direction and the weft direction.

[0030] [7] The airbag pad according to any one of claims 1 to 6, wherein the weight per unit area of ​​the airbag pad is 220 g / m 2 the following.

[0031] [8] The airbag mat according to any one of claims 1 to 7, wherein the warp-to-weft ratio of the tear strength of the airbag mat is 0.94 or less when the smaller of the warp direction and the weft direction is divided by the larger of the warp-to-weft ratio.

[0032] [9] The airbag mat according to any one of claims 1 to 8, wherein the tear strength of the airbag mat in the warp direction and / or the weft direction is 100 N or more.

[0033]

[10] The airbag padding fabric according to any one of claims 1 to 9, wherein the stiffness in the warp direction and / or the weft direction of the airbag padding fabric is 10N or less.

[0034]

[11] The airbag padding fabric according to any one of claims 1 to 10, wherein the tensile elongation in the warp direction and / or the weft direction of the airbag padding fabric is 10% or more.

[0035]

[12] An airbag, comprising: an airbag patch according to any one of claims 1 to 11, the airbag patch being provided so as to cover at least a portion of an airbag main body cloth.

[0036]

[13] An airbag according to Technical Solution 12, wherein the airbag pad is attached in such a manner that the direction with a smaller cover factor in the warp direction and the weft direction of the airbag pad is parallel to the deployment direction of the airbag.

[0037] Effects of the Invention

[0038] According to the present invention, there is provided an airbag mat having excellent storage properties and excellent cut resistance during airbag deployment. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 It is a schematic diagram of a curtain airbag with a cushion cloth (curtain airbag assembly).

[0040] Figure 2 It is a schematic diagram used to illustrate the internal pressure test when the glass cut is unfolded. DETAILED DESCRIPTION

[0041] Hereinafter, embodiments of the present invention will be described in detail. The present invention is not limited to the following embodiments, and can be implemented with various modifications within the scope of the gist thereof.

[0042] In the present specification, the pad refers to a fabric attached to the main body fabric of the airbag. Here, the main body fabric refers to a bag-shaped structure that is inflated by gas generated by an inflator, etc., and can be a main body fabric composed of two or more fabrics, a main body fabric composed of a bag-shaped fabric called OPW, etc. The main body fabric attached to the airbag refers to a state of being directly or indirectly connected to the main body fabric of the airbag or a state of being stored together with the main body fabric of the airbag.

[0043] In the airbag pad fabric of the present invention, from an economic point of view, the raw materials of the warp and weft yarns constituting the airbag fabric are preferably the same raw materials as the airbag main body fabric, but are not limited thereto. For example, polyamide fiber, polyester fiber, vinylon fiber, high-strength polyethylene, polyolefin fibers such as polypropylene, vinyl chloride and vinylidene chloride fibers, fluorine fibers including polytetrafluoroethylene, polysulfone fibers, polyphenylene sulfide fibers (PPS), polyether ketone fibers (PEEK) fibers, polyalkyl ketone fibers, polyimide fibers, polyetherimide fibers, cellulose fibers including high-strength rayon, acrylic fibers, carbon fibers, glass fibers, silicon carbide fibers (SiC) fibers, aluminum oxide fibers, etc. can be used alone or in combination. From the perspective of strength and elongation and economy, synthetic fibers are preferred, and polyamide fibers and polyester fibers are preferred.

[0044] The total fineness of the warp and weft yarns constituting the pad is preferably 100 dtex or more and 750 dtex or less, more preferably 150 dtex or more and 550 dtex or less, further preferably 180 dtex or more and 550 dtex or less, further preferably 210 dtex or more and 550 dtex or less, and particularly preferably 210 dtex or more and 370 dtex or less. Fibers having different total finenesses may also be used for the warp and weft yarns. By making the total fineness 100 dtex or more, the strength during development and expansion can be withstood. On the other hand, by making the total fineness 750 dtex or less, the fabric becomes soft, the storage property is improved, and high-speed development is also possible.

[0045] There is no particular limitation on the shape of the cross section of the single yarn of the warp and weft yarns, and they may be any of the special-shaped cross-section yarns such as circular cross-section, triangular cross-section, hexagonal cross-section, flat cross-section, etc. From the viewpoint of maximizing strength and elongation, a circular cross-section is preferred.

[0046] The weight of the pad (weight per unit area) is preferably 220 g / m 2 Below, more preferably 200g / m 2 Below, more preferably 180g / m 2 By making the weight per unit area 220g / m 2The lower limit of the weight per unit area of ​​the pad is not limited and may be 50 g / m 2 above.

[0047] The thickness of the pad is preferably 0.3 mm or less, more preferably 0.25 mm or less, and further preferably 0.2 mm or less. By setting the thickness of the pad to 0.3 mm or less, the stowability of the airbag can be improved. From the viewpoint of cut resistance, the thickness of the pad is preferably 0.1 mm or more, and further preferably 0.15 mm or more.

[0048] Warp cover factor CF of the pad x and the latitudinal cover factor CF y The sum of CF is preferably 1500 or more and 2200 or less. CF x With CF y It is expressed by the following formula:

[0049] CF x =(D x ×√F x )

[0050] CF y =(D y ×√F y )

[0051] Where D x F is the number of warp yarns per 2.54 cm (warp density), x is the warp yarn fineness (dtex) of the fabric, D y F is the number of weft yarns per 2.54 cm (weft density), y is the fineness (dtex) of the weft yarn that makes up the fabric. x With CF y By setting the CF to 2200 or less, an airbag having excellent resistance to cuts and excellent storage properties during airbag deployment can be obtained. On the other hand, by setting the CF to 1500 or more, the tissue can be made denser to a certain extent, and the tissue can be prevented from shifting and becoming uneven during cutting and sewing. In addition, the following situation can be prevented: when tension acts on the pad during airbag deployment, force acts on the connection between the pad and the airbag body, and the connection between the pad and the airbag body is destroyed due to the slippage of the fabric structure. CF is more preferably 1600 or more and 1950 or less, and even more preferably 1800 or more and 1900 or less.

[0052] Warp cover factor CF of the pad x and the latitudinal cover factor CF y The ratio (longitude and latitude ratio) of the cover factor is preferably less than 0.80. x and CFy In order to make the longitudinal cover factor CF x and the latitudinal cover factor CF y The ratio is below 0.80, and it needs to be designed as CF x and CF y One of them is smaller than the other. x and CF y The smaller of the two can be used, but from the perspective of dimensional stability of the base fabric, it is preferred to make CF y By reducing the weft density, the difference in the curvature of the warp and weft can be reduced, thereby reducing the difference in the dimensional change of the warp and weft. x and the latitudinal cover factor CF y The mat cloth having a ratio of 0.80 or less is attached to the airbag main body cloth, and an airbag having excellent cut resistance during airbag deployment and excellent stowage properties can be obtained.

[0053] When the curtain airbag is deployed, the buffer surface will interfere with the side window glass, obstacles inside and outside the vehicle body, etc., and it is easy to cause cuts in the deployment direction (i.e., the vertical direction) of the curtain airbag. In the case of a curtain airbag having excellent cut resistance when deployed by connecting a pad cloth to a curtain-shaped airbag main body cloth, by increasing the coverage factor in the direction perpendicular to the cut direction, the amount of fibers per unit length of the cut is increased, and the absorption of energy caused by fiber breakage can be increased. In addition, by reducing the coverage factor in the direction parallel to the cut direction, it is easy to cause yarn displacement of the fibers in the direction perpendicular to the cut direction, and the absorption of energy when each fiber breaks in the direction perpendicular to the cut direction can be increased. Furthermore, by making the coverage factor in the direction parallel to the cut direction smaller than the coverage factor in the direction perpendicular to the cut direction, the energy of the cut can be dissipated in a direction perpendicular to the cut direction, and the cut resistance can be improved. In addition, by reducing the CF x With CF y The ratio of the fiber yarn displacement is easy to cause, the stiffness is reduced, and the storage of the airbag can be improved. The curtain airbag is usually folded into a roll or bellows shape when stored. At this time, bending deformation is applied to the yarn strips in the direction parallel to the cut direction. By reducing the coverage factor in the direction parallel to the cut direction, the resistance to bending deformation can be reduced, and the storage is improved, so it is preferred. Warp coverage factor CF x and the latitudinal cover factor CF y The ratio of is preferably 0.75 or less, more preferably 0.70 or less. On the other hand, from the viewpoint of handling, the warp cover factor CF x and the latitudinal cover factor CF yThe ratio of is preferably 0.30 or more, more preferably 0.50 or more, and further preferably 0.60 or more. In order to exert the above effect, the warp cover factor CF of the pad is x and the latitudinal cover factor CF y The absolute value of the larger one of the above is preferably in the range of 900 to 1300, more preferably in the range of 950 to 1250, and even more preferably in the range of 1000 to 1200. On the other hand, in order to exert the above effect, the warp cover factor CF of the pad is x and the latitudinal cover factor CF y The absolute value of the smaller one of them is preferably in the range of 300 to 1200, more preferably in the range of 400 to 1100, and further preferably in the range of 500 to 1000.

[0054] In the case of attaching a pad to a curtain-shaped airbag main body cloth, in order to improve the cut resistance, it is preferred to attach the pad in a manner such that the direction with a smaller cover factor in the warp and weft directions of the pad is parallel to the deployment direction of the airbag. By configuring the pad in a manner such that the direction with a smaller cover factor in the warp and weft directions of the pad is parallel to the deployment direction of the airbag, the above-mentioned energy absorption efficiency can be improved. On the other hand, there is also the following situation: by attaching the pad in a manner such that the direction with a larger cover factor in the warp and weft directions of the pad is parallel to the deployment direction of the airbag, when the pad is cut, the pad will undulate near the cut part, and a gap will be generated between the pad and the main body cloth, thereby protecting the main body cloth from the influence of the cut. In addition, it is also possible to configure the pad in a manner such that the mesh of the pad is in an oblique direction relative to the deployment direction. When the pad is attached to the airbag main body cloth, whether or not the pad is connected to the airbag main body cloth and the method of connection are not particularly limited. For example, the airbag main body cloth and the pad may be sewn together, or connected with a rope or a rectangular strip of raw material, or the pad may be squeezed out by the deployment of the airbag main body cloth and stored together with the airbag main body cloth. It is important to design the pad between the airbag main body cloth and the obstacle etc. when the airbag main body cloth interferes with the obstacle etc. inside and outside the vehicle body during deployment of the airbag. By designing in this way, the function of reducing the harmfulness of cuts caused by obstacles etc. to the airbag main body cloth can be exerted. In addition, the shape of the pad is not particularly limited, and can be designed in consideration of the effect on the cut resistance of the airbag main body cloth and the storage property.

[0055] When the mat is connected to the curtain-shaped airbag main body cloth, the mat is attached in such a way that the direction with a smaller cover factor in the warp direction and the weft direction of the mat is parallel to the deployment direction of the airbag, thereby achieving a curtain airbag with excellent stowability. This is because by reducing the cover factor in the vertical direction that is deformed when the curtain airbag is rolled or bent, the resistance to bending deformation can be reduced.

[0056] The characteristics of the pad are that the dynamic tearing property P described below x and P y At least one of is 0.8 or more. It may also be that P x and P y The larger one is greater than 0.8, and the smaller one is less than 0.8. x and P y At least one value of is preferably 0.85 or more, more preferably 0.9 or more. x and P y The upper limit of P is not particularly limited, but from the perspective of using a soft and available raw material suitable for an airbag pad to manufacture, P x and P y The upper limit is 20 or less.

[0057] The value of the dynamic tearing property P is calculated from the results of the material puncture resistance and dynamic tearing resistance test described in Japanese Industrial Standard JIS T 8050. Specifically, it is expressed by the following formula:

[0058] P x =E / (T x ×F x )×1000

[0059] P y =E / (T y ×F y )×1000

[0060] Where E is the kinetic energy (J) of the block and the tool in the dynamic tear test (performance level 3) described in Japanese Industrial Standard JIS T 8050, and T x It is the average value (mm) of the tear length in the warp direction in the dynamic tear test (performance level 3) described in Japanese Industrial Standard JIS T 8050. x is the warp yarn fineness (dtex) of the padding, T y is the average value (mm) of the tear length in the weft direction in the dynamic tear test (performance level 3) described in Japanese Industrial Standard JIS T 8050, and F y It is the fineness (dtex) of the weft yarns that make up the pad.

[0061] T x and T yThey are the average tear lengths (mm) in the warp direction and the weft direction in the dynamic tear test described in Japanese Industrial Standard JIS T 8050, respectively. Among them, the following adjustment is made: a tool holding block and a tool with a mass of 1000g are used, so that the kinetic energy of the block and the tool calculated by the average speed when the block falls continuously 5 times becomes 6.6J~7.0J. That is, it is set as a test condition for evaluating the performance of the performance level 3 described in Japanese Industrial Standard JIS T 8050. In addition, in the measurement of the tear length in the warp direction and the weft direction, at least 3 test pieces are used to perform tests in each direction, and the average tear length in each direction is calculated. E is the kinetic energy (J) of the block and the tool calculated by the average speed, and takes a value in the range of 6.6J~7.0J.

[0062] In the dynamic tear test, a tearing knife capable of making a hole in the test piece is dropped onto the test piece, causing blunt tearing damage to the test piece. At this time, the test piece is given a dynamic puncture mode and tearing mode in one direction. These damage modes are similar to the cut damage modes caused when the buffer surface interferes with the side window glass, obstacles inside and outside the vehicle body, etc. when the curtain airbag is deployed.

[0063] Since the damage mode in the dynamic tear test is similar to the cutting damage mode when the curtain airbag is deployed, the fineness F of the padding fabric is adjusted to x and / or F y Smaller, tear length T x and / or T y The smaller the diameter and the higher the value of the dynamic tear characteristic P, the better the storage property of the cushioning cloth can be. Even when the curtain airbag interferes with the side window glass, obstacles inside or outside the vehicle body, etc. during deployment, the reduction in the internal pressure holding performance of the buffer due to cuts can be prevented, and the impact absorption performance required by the airbag can be maintained.

[0064] T-shirt x or T y The value of is preferably 40 mm or less, more preferably 30 mm or less, and further preferably 20 mm or less. x or T y The value of T is 40 mm or less, which can improve the cut resistance against glass sheets when the airbag is deployed. x and T y The lower limit of T is not particularly limited, but is considered to be suitable for manufacturing airbag pads using soft and available raw materials. x and T y The lower limit can be above 5 mm.

[0065] From the perspective of cut resistance, the T x With T yThe ratio (i.e., T x and T y The smaller of the two is divided by the larger of the two. ) is preferably 0.94 or less, more preferably 0.9 or less, and further preferably 0.8 or less. By making T x With T y The ratio of is 0.94 or less, that is, by making the tear length in the warp direction and the tear length in the weft direction in the dynamic tear test of the pad cloth anisotropic, the energy of the cut can be dissipated in different directions, and the cut resistance can be improved. x With T y The lower limit of the ratio is not limited and may be 0.2 or more.

[0066] The tear strength of the pad in the warp and / or weft direction is preferably 100 N or more, more preferably 150 N or more, and further preferably 200 N or more. By setting the tear strength in the warp and / or weft direction to 100 N or more, the resistance to cuts by glass sheets during airbag deployment can be improved. The upper limit of the tear strength is not limited, but in view of the use of soft and available raw materials suitable for airbag pads, the upper limit of the tear strength may be 1000 N or less.

[0067] The warp-to-weft ratio of the tear strength of the pad (i.e., the smaller of the warp and weft divided by the larger of the other) is preferably 0.94 or less, more preferably 0.9 or less, and further preferably 0.87 or less. By setting the warp-to-weft ratio of the tear strength to 0.94 or less, the tear strength in the warp direction and the weft direction of the pad has anisotropy, so that the energy of the cut is dissipated in the direction of the lower tear strength, and the cut resistance in the cut direction can be improved. The lower limit of the warp-to-weft ratio of the tear strength is not limited, and can be 0.2 or more.

[0068] The stiffness of the pad in the warp and / or weft direction is preferably 10N or less, the stiffness in both the warp and weft directions is more preferably 10N or less, and the stiffness in both the warp and weft directions is further preferably 8N or less. By setting the stiffness to 10N or less, the stowability of the airbag can be improved. The lower limit of the stiffness is not limited, but from the perspective of manufacturing with generally available raw materials, the lower limit of the stiffness is 1N or more.

[0069] The slip resistance of the pad is preferably 10N or more and 400N or less in both the warp and weft directions. By setting the slip resistance to 10N or more, the following situation can be prevented: when tension acts on the pad during the deployment of the airbag, the force acts on the connection between the pad and the airbag body, and the connection between the pad and the airbag body is destroyed due to the slippage of the fabric structure. The slip resistance of the pad can be increased by increasing the cover factor and removing the oil attached to the fiber. On the other hand, by setting the slip resistance to 400N or less, it is easy to cause the yarn displacement of the fiber, and the energy of the cut can be dissipated, thereby improving the cut resistance. In order to take into account both the connection stability and the cut resistance of the pad and the airbag body, the oil attached to the fiber can be appropriately removed by, for example, washing the woven pad with water. The slip resistance of the pad is more preferably 30N or more and 300N or less in both the warp and weft directions.

[0070] The tensile elongation of the padding cloth in the warp and / or weft direction is preferably 10% or more. By setting the tensile elongation to 10% or more, it is possible to prevent the elongation of the base fabric of the airbag body from being hindered by the attached padding cloth during airbag deployment, thereby preventing the deployment action of the airbag from becoming unstable and / or reducing the deployment speed. In addition, when the airbag is deployed, tension is not easily applied to the padding cloth, and the connection between the padding cloth and the airbag body is not easily destroyed due to slippage of the fabric structure. The tensile elongation is more preferably 20% or more, and even more preferably 25% or more. From the viewpoint of cut resistance, the tensile elongation is preferably 100% or less.

[0071] In the production of the pad cloth, for example, looms such as air jet looms, rapier looms, projection looms, and multi-phase looms can be used, but are not limited to these. During weaving, barbed-loop side supports and full-surface side supports can be used. The weaving structure of the pad cloth is not particularly limited, and plain weave, 2 / 2 basket weave, 3 / 3 basket weave, 2 / 1 basket weave, twill weave, ripstop weave (Japanese: リップストップ), etc. can be used, and they can also be composited. In addition, elastomers, thermoplastic resins, or laminated films, or other covering materials can be coated on both sides or one side of the pad cloth. In order to improve the cut resistance, the pad cloth can be used by overlapping multiple sheets or combining with other fabrics.

[0072] Example

[0073] Next, the embodiment of the present invention will be specifically described by way of examples and comparative examples, but the present invention is not limited to these examples. In addition, the measurement method, evaluation method, etc. used are as follows.

[0074] (1) Fineness

[0075] The apparent fineness of yarn taken out of fabric was measured according to the method for measuring the apparent fineness of yarn (method A) described in Appendix H of Japanese Industrial Standard JIS L 1096: 2010. The load for measuring the length of the yarn stretched straight was 9.3 mN / tex, and 20 continuous yarns of each warp and weft were measured, and the average value was recorded.

[0076] (2) Weight per unit area, density, and thickness

[0077] Weight per unit area: Five samples of 100 mm x 100 mm were collected and measured according to the method B (ISO method) for measuring the mass per unit area under standard conditions described in Japanese Industrial Standards JIS L 1096: 2010. The weight per unit area of ​​each sample was measured and the average value was calculated.

[0078] Density: Based on the fabric density method A described in Japanese Industrial Standard JIS L 1096:2010, 2.54 cm square samples were collected at 5 locations, the number of constituent yarns of each sample was counted using an optical microscope, and the average value was calculated.

[0079] Thickness: Five samples of 100 mm x 100 mm were collected and measured according to the thickness method B described in Japanese Industrial Standard JIS L 1096: 2010. The applied pressure was 1 kPa and a presser foot with a diameter of 10.5 mm was used. The thickness of each sample was measured and the average value was calculated.

[0080] However, when the size of the test piece is insufficient for the above-mentioned measurements of weight per unit area, density and thickness, a sample of as wide a range as possible may be collected for measurement.

[0081] (3) Coverage factor

[0082] The following formulas were used for calculation.

[0083] Via:CF x =(D x ×√F x )

[0084] Weft: CF y =(D y ×√F y )

[0085] Longitude and latitude ratio: CF x / CF y CF y / CF x The smaller of

[0086] Latitude and longitude: CF x+CF y

[0087] Where D x F is the number of warp yarns per 2.54 cm (warp density), x is the warp yarn fineness (dtex) of the fabric, D y F is the number of weft yarns per 2.54 cm (weft density), y It is the fineness of the weft yarns that make up the fabric (dtex).

[0088] (4) Tensile elongation and tear strength

[0089] The measurement was performed according to the following method described in Japanese Industrial Standard JIS L 1096: 2010. The tear strength was calculated by dividing the smaller one of the warp and weft by the larger one to obtain the warp and weft ratio.

[0090] Tensile elongation: Elongation in the tensile strength and elongation A method (strip method (Japanese: Stripp method))

[0091] Tear strength: Tear strength A method (single tongue test method)

[0092] (5) Stiffness

[0093] The measurement was performed according to the method described in ASTM D4032-08 (2016).

[0094] (6) Slip resistance

[0095] The measurement was carried out according to the method described in ASTM D6479.

[0096] (7) Dynamic tear length T x , T y

[0097] The material resistance to puncture and dynamic tearing was measured based on the test described in Japanese Industrial Standard JIS T 8050:2005. The following adjustments were made: a tool holding block and a tool with a mass of 1000g were used so that the kinetic energy of the block and the tool calculated from the average speed when the block fell five times continuously became 6.6J to 7.0J, and the value at this time was recorded as the kinetic energy E (J). The test piece was cut with scissors in such a way that the expanded part of the double-layer bag woven structure became the center of the test piece (the puncture and tearing part of the tool), and was fixed to the test piece mounting block in such a way that the resin-coated surface was on the outside. In the test, at least 3 test pieces were tested in each of the warp and weft directions, and the average tear length in each direction was calculated as T. x , T y . In addition, the smaller of the longitude and latitude is divided by the larger one to obtain the value of the longitude and latitude ratio.

[0098] (8) Dynamic tearing properties P x , P y

[0099] P x =E / (T x ×F x )×1000

[0100] P y =E / (T y ×F y )×1000

[0101] Where E is the kinetic energy (J) of the block and the tool in the dynamic tear test (performance level 3) described in Japanese Industrial Standard JIS T 8050, and T x It is the average value (mm) of the tear length in the warp direction in the dynamic tear test (performance level 3) described in Japanese Industrial Standard JIS T 8050. x is the warp yarn fineness (dtex) of the fabric, T y is the average value (mm) of the tear length in the weft direction in the dynamic tear test (performance level 3) described in Japanese Industrial Standard JIS T 8050, and F y It is the fineness of the weft yarns that make up the fabric (dtex).

[0102] (9) Storage capacity (roll diameter)

[0103] Follow the steps below to create Figure 1 A side curtain airbag (1) with a padding (8) of the shape shown. Nylon 66 fiber with a total fineness of 235 dtex, a raw yarn strength of 8.5 cN / dtex, and a hot water dimensional change rate of 8.0% is used for warp and weft yarns, and an electronic jacquard device and a rapier loom are used. Figure 1 The curtain airbag main body fabric with a capacity of 24L was woven into the shape shown in the figure. Next, both sides of the fabric were woven with 80g / m 2 A liquid silicone composition was applied and heat treated at 180°C for 1 minute in a dryer. The weaving structure of the connecting portion that closes the bag changes in the order of bag weave, 2 / 2 basket weave (4 strands), bag weave (including 4 strands with double-sided different-color patterns), 3 / 3 basket weave (6 strands), and bag weave. The weaving structure of the double-layer structure portion is a plain weave, and the double-layer structure of the bag weave is partially connected by about 1% in the portion on the outside of the connecting portion of the bag that is not expanded. Figure 1As shown, the padding cloth is sewn by upper and lower sewing parts (9) in such a way that the padding cloth covers the portion of the airbag with a length of 600 mm in the vertical direction and a length of 1000 mm in the horizontal direction, thereby fixing the padding cloth to the airbag main body cloth. The obtained curtain airbag with padding cloth is rolled into a roll in the vertical direction and fixed with a belt. The circumference of 5 parts of the roll at this time is measured with a tape measure, and the average value is divided by pi to calculate the roll diameter. The case where the roll diameter is less than 22 mm is evaluated as A, the case where the roll diameter is greater than 22 mm and less than 25 mm is evaluated as B, the case where the roll diameter is greater than 25 mm and less than 28 mm is evaluated as C, and the case where the roll diameter is greater than 28 mm is evaluated as D.

[0104] (10) Internal pressure when glass cuts open

[0105] Will Figure 1 The side curtain airbag (1) with a pad (8) of the shape shown is rolled up in the vertical direction and fixed with a belt. A 2.0 mol hybrid inflator is installed in the inflator mounting part (3) to form a curtain airbag assembly. Using this assembly, a collision test is carried out. That is, Figure 2 As shown schematically, an object called a collision head (11) is collided with the airbag assembly under the following conditions in response to the deployment of the airbag assembly, thereby simulating the collision action of an actual vehicle. A 4.5 kg collision head is used, and the head speed is set to 24 km / hr. The collision time is set to 30 milliseconds after the inflator is activated, and the collision point is set to the time when the airbag is deployed. Figure 1 The + marked part (7: center of the protection area). On the opposite side of the impact head relative to the component position, a plate (14) is set in a manner along the deployment of the airbag, and a coarse wood file (13) manufactured by Husan Co., Ltd. (flat type, roughness 10 cuts / cm) is installed in the vertical direction at the impact point. 2 , length 250mm×width 25mm×thickness 6mm) as a jig to simulate glass fragments. The position of the file was fixed so that the center of the file was at the collision point, the rough file side was facing the buffer contact surface, and the disk surface (valley) of the file and the surface of the plate were on the same plane. The internal pressure during deployment was measured for the airbag deployment. Figure 1 The collision test was carried out according to the usual procedure, and the case where the internal pressure of the buffer after 1000 milliseconds after deployment was 30 kPa or more was set as A, the case where the internal pressure was 25 kPa or more and less than 30 kPa was set as B, the case where the internal pressure was 15 kPa or more and less than 25 kPa was set as C, and the case where the internal pressure was less than 15 kPa was set as D.

[0106] (11) Sewing part slips

[0107] After the test (10) was performed, the degree of slippage of the sewn portion of the patch cloth and the airbag main body cloth was evaluated in three stages: B was a case where no damage was observed, C was a case where the patch cloth structure was loose and partially slipped, and D was a case where the patch cloth partially fell off the airbag main body cloth.

[0108] (12)Total score

[0109] In the results of (9) to (11), A was set to 3 points, B was set to 2 points, C was set to 1 point, and D was set to 0 points, and the product of the points of each item was expressed as the total score.

[0110] [Example 1]

[0111] Nylon 66 fiber with a raw yarn strength of 8.5 cN / dtex and a hot water dimensional change rate of 8.0% was used for warp and weft yarns, and the number of weft insertions was reduced relative to the warp density, and a plain weave fabric was woven using a water jet loom. Next, the fabric was washed with warm water at 80°C and dried using a cylinder. The total fineness of the fibers constituting the fabric was 205 dtex. The warp / weft density and fabric properties of the fabric obtained in Example 1 are shown in Table 1.

[0112] [Example 2 to Example 4, Comparative Example 1]

[0113] Nylon 66 fiber with a raw yarn strength of 8.5 cN / dtex and a hot water dimensional change rate of 8.0% was used for warp and weft, and the number of weft insertions was reduced relative to the warp density, and a plain weave fabric was woven using a water jet loom. Next, the fabric was washed with warm water at 80°C and dried using a cylinder. The total fineness of the fibers constituting the fabric was 235 dtex. The warp / weft density and fabric properties of the fabrics obtained in Examples 2 to 4 and Comparative Example 1 are shown in Table 1.

[0114] [Examples 5, 6, Comparative Examples 2, 4, 5]

[0115] Nylon 66 fiber with a raw yarn strength of 8.5 cN / dtex and a hot water dimensional change rate of 8.0% was used for warp and weft, and the number of weft insertions was reduced relative to the warp density, and a plain weave fabric was woven using a water jet loom. Next, the fabric was washed with warm water at 80°C and dried using a cylinder. The total fineness of the fibers constituting the fabric was 470 dtex. The warp / weft density and fabric properties of the fabrics obtained in Examples 5 and 6 and Comparative Examples 2, 4, and 5 are shown in Table 1.

[0116] [Comparative Example 3]

[0117] Nylon 66 fiber with a raw yarn strength of 8.5 cN / dtex and a hot water dimensional change rate of 8.0% was used for warp and weft, and a plain weave fabric was woven using a water jet loom in such a way that the number of weft insertions was equal to the warp density. Next, the fabric was washed with warm water at 80°C and dried using a cylinder. The total fineness of the fibers constituting the fabric was 700 dtex. The warp / weft density and fabric properties of the obtained fabric are shown in Table 1.

[0118] [Table 1]

[0119]

[0120] [Example 7]

[0121] In the single side of the curtain airbag main body fabric obtained through the curtain airbag main body fabric production project Figure 1 The fabric obtained in Example 1 was sewn at the position shown in FIG. 1 by using a sewing yarn of 1400 dtex and a stitch count of 45 stitches / 10 cm in one row to prepare a pad. At this time, the pad was installed in such a manner that the direction with a smaller cover factor (the weft direction) in the warp direction and the weft direction was parallel to the deployment direction of the airbag. Figure 1 The inner tube is inserted as shown in the figure mark 4, and the expansion gas is guided from the gas supply port at the rear end to the front expansion part and the rear expansion part. The inner tube uses a 25g / m2 plain woven fabric made of polyamide 6.6 fiber, 700dtex / 105f, with 41 strands × 41 strands / 2.54cm in the warp and weft directions. 2 Silicone coated cloth. The cloth is sewn obliquely into a cylindrical shape with a diameter that can fit into the gas supply port. Sewing is performed by using a 1400 dtex sewing yarn and a needle number of 45 needles / 10 cm in one row of true sewing. The front end of the inner tube is open, and the sewing part is set to the upper side, and the notch for gas supply of the rear inflation part is set to the lower side. As shown in Table 2, the properties of the obtained curtain airbag are very excellent in storage, and the cut resistance during deployment is average, and there is no slippage of the sewn part.

[0122] [Example 8]

[0123] The curtain airbag was evaluated using the fabric obtained in Example 2 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag were very excellent in stowability, average in cut resistance during deployment, and no slippage of the sewn portion.

[0124] [Example 9]

[0125] The curtain airbag was evaluated using the fabric obtained in Example 3 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag were very excellent in stowability, good in cut resistance during deployment, and no slippage of the sewn portion.

[0126] [Example 10]

[0127] The curtain airbag was evaluated using the fabric obtained in Example 4 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag were very excellent in stowability, good in cut resistance during deployment, and no slippage of the sewn portion.

[0128] [Example 11]

[0129] The curtain airbag was evaluated using the woven fabric obtained in Example 5 in the same manner as in Example 7. As shown in Table 2, the obtained curtain airbag had excellent storage properties, very good cut resistance during deployment, and no slippage of the sewn portion.

[0130] [Example 12]

[0131] The curtain airbag was evaluated using the fabric obtained in Example 6 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag showed that the patch had loose texture and partially slipped, but excellent stowability and excellent cut resistance during deployment.

[0132] [Comparative Example 6]

[0133] The curtain airbag was evaluated using the fabric obtained in Comparative Example 1 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag were excellent in stowability and no slippage of the sewn portion, but poor in cut resistance during deployment.

[0134] [Comparative Example 7]

[0135] The curtain airbag was evaluated using the fabric obtained in Comparative Example 2 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag were fair in cut resistance during deployment, no slippage of the sewn portion, but poor in stowability.

[0136] [Comparative Example 8]

[0137] The curtain airbag was evaluated using the fabric obtained in Comparative Example 3 in the same manner as in Example 7. As shown in Table 2, the characteristics of the curtain airbag were very good in cut resistance during deployment and no slippage of the sewn portion, but poor in stowability.

[0138] [Comparative Example 9]

[0139] The curtain airbag was evaluated using the fabric obtained in Comparative Example 4 in the same manner as in Example 7. As shown in Table 2, the properties of the obtained curtain airbag showed that there was no slippage of the sewn portion, but the stowage property and the cut resistance during deployment were both average.

[0140] [Comparative Example 10]

[0141] The curtain airbag was evaluated using the woven fabric obtained in Comparative Example 5 in the same manner as in Example 7. The properties of the obtained curtain airbag were excellent in stowability as shown in Table 2, but the cut resistance during deployment was average and slippage of the sewn portion occurred.

[0142] [Example 11]

[0143] The curtain airbag was evaluated by the same method as in Example 7 using the fabric obtained in Example 5. However, when attaching the patch to the airbag main body fabric, the patch was attached so that the direction with a larger cover factor (longitudinal direction) in the warp and weft directions was parallel to the deployment direction of the airbag. As shown in Table 2, the properties of the obtained curtain airbag were average in terms of storage performance and cut resistance during deployment, and there was no slippage of the sewn portion.

[0144] [Table 2]

[0145]

[0146] Industrial Applicability

[0147] By attaching the airbag mat of the present invention to the main body fabric of the airbag, an airbag having excellent storage properties and excellent cut resistance during airbag deployment can be provided. In particular, the airbag mat of the present invention can be preferably used in a curtain airbag for protecting a human body from the side.

[0148] Description of Reference Numerals

[0149] 1. Side curtain airbag; 2. Seam (bag junction); 3. Inflator installation; 4. Inner tube; 5. Opening; 6. Joint; 7. Center of the protection area; 8. Pad; 9. Sewing part of the pad and the airbag main body cloth; 11. Impact head; 12. Side curtain airbag installation; 13. File; 14. Plate.

Claims

1. An airbag padding fabric, which is attached to a main body fabric of an airbag, wherein: The airbag pad is a fabric. In the fabric, the dynamic tearing property P expressed by the following formula x and P y At least one of the following is 0.8 or more: P x =E / (T x ×F x )×1000 P y =E / (T y ×F y )×1000 Where E is the kinetic energy of the block and the cutter in the dynamic tear test of performance level 3 as described in Japanese Industrial Standard JIS T 8050, in J, T x It is the average tear length in the warp direction in the dynamic tear test of performance level 3 described in Japanese Industrial Standard JIS T 8050, the unit is mm, F x It is the warp yarn fineness of the fabric, measured in dtex, T y It is the average tear length in the weft direction in the dynamic tear test of performance level 3 described in Japanese Industrial Standard JIS T 8050, in mm, F y It is the fineness of the weft yarn that makes up the fabric, measured in dtex. In the airbag pad, the warp cover factor CF represented by the following formula: x and the latitudinal cover factor CF y The ratio of CF x and CF y The smaller of the two divided by the larger of the two is greater than 0.30 and less than 0.80: CF x =(D x ×√F x ) CF y =(D y ×√F y ) Where D x is the number of warp yarns per 2.54 cm, i.e. the warp yarn density, F x It is the fineness of the warp yarns that make up the fabric, measured in dtex, D y is the number of weft yarns per 2.54 cm, i.e. the weft yarn density, F y It is the fineness of the weft yarn that makes up the fabric, measured in dtex.

2. The airbag pad according to claim 1, wherein: Regarding the T of the airbag pad x With T y The ratio of x and T y The smaller of the two divided by the larger one is less than 0.

94.

3. The airbag pad according to claim 1 or 2, wherein: Dynamic tearing properties of the airbag pad x and P y At least one of them is 0.9 or more and 20 or less.

4. The airbag pad according to claim 1 or 2, wherein: Regarding the T of the airbag pad x With T y The ratio of x and T y The smaller one of the two is divided by the larger one, and is greater than or equal to 0.2 and less than or equal to 0.

8.

5. The airbag pad according to claim 1 or 2, wherein: The T of the airbag pad x and / or T y Less than 20mm.

6. The airbag pad according to claim 1, wherein: The warp cover factor CF of the airbag pad is x and the latitudinal cover factor CF y The ratio of CF x and CF y The smaller one of the two values ​​divided by the larger one is 0.30 or more and 0.70 or less.

7. The airbag pad according to claim 1, wherein: The warp cover factor CF of the airbag pad x and the latitudinal cover factor CF y The sum of is greater than 1500 and less than 2200.

8. The airbag pad according to claim 1 or 2, wherein: The total fineness of the warp yarn and the weft yarn constituting the airbag padding fabric is 210 dtex or more and 550 dtex or less.

9. The airbag pad according to claim 1 or 2, wherein: The airbag pad has a slip resistance of 10 N or more and 400 N or less in both the warp direction and the weft direction.

10. The airbag pad according to claim 1 or 2, wherein: The weight per unit area of ​​the airbag pad is 220 g / m 2 the following.

11. The airbag pad according to claim 10, wherein: The weight per unit area of ​​the airbag pad is 50 g / m 2 Above and 180g / m 2 the following.

12. The airbag pad according to claim 1 or 2, wherein: The warp-to-weft ratio of the tear strength of the airbag mat is 0.94 or less when the smaller one of the warp direction and the weft direction is divided by the larger one.

13. The airbag pad according to claim 1 or 2, wherein: The tear strength of the airbag pad in the warp direction and / or the weft direction is 100N or more.

14. The airbag pad according to claim 1 or 2, wherein: The stiffness of the airbag padding fabric in the warp direction and / or the weft direction is 10N or less.

15. The airbag pad according to claim 1 or 2, wherein: The tensile elongation of the airbag pad in the warp direction and / or the weft direction is greater than 10%.

16. The airbag pad according to claim 1 or 2, wherein: The cross-sectional shape of a single yarn of the warp yarn and the weft yarn constituting the airbag patch fabric is circular.

17. The airbag pad according to claim 1 or 2, wherein: The airbag pad has a thickness of 0.3 mm or less and 0.1 mm or more.

18. The airbag pad according to claim 1, wherein: The warp cover factor CF of the airbag pad x and the latitudinal cover factor CF y The absolute value of the larger one of is in the range of 1000 to 1200.

19. The airbag pad according to claim 1, wherein: The warp cover factor CF of the airbag pad x and the latitudinal cover factor CF y The absolute value of the smaller one of is in the range of 500 to 1000.

20. An air bag, wherein: This airbag is provided with the airbag patch cloth according to any one of claims 1 to 19 so that the airbag patch cloth covers at least a part of an airbag main body cloth.

21. The airbag according to claim 20, wherein: The airbag mat is attached so that one of the warp direction and the weft direction having a smaller cover factor is parallel to the deployment direction of the airbag.

22. The airbag according to claim 20, wherein: The airbag patch is attached so that one of the warp direction and the weft direction of the airbag patch, in which the cover factor is larger, is parallel to the deployment direction of the airbag.

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