JPH06234345A - Air bag - Google Patents

Abstract

PURPOSE:To provide an air bag of high reliability well-balanced with high exhaust action and high pressure both attained. CONSTITUTION:In an uncoated air bag formed of synthetic fiber cloth, the cloth is formed of the combination of plain weave backing fabric and rip stop backing fabric. The plain weave backing fabric is used on the face side of the air bag, and the rip stop backing fabric is used on the non-face side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag made of highly reliable non-coated base cloth.

[0002]

2. Description of the Related Art In recent years, the practical use of airbags for ensuring the safety of passengers in automobiles has been rapidly increasing. In the event of a car collision, the airbag receives high-pressure gas when the sensor receives a shock from the collision, and the high-pressure gas causes the airbag to inflate momentarily to protect the occupant's face especially in the event of a collision. To do. Conventionally, 300 to 1000 denier nylon 6.6 is used for airbags.
To improve heat resistance, air barrier properties, etc., a plain woven fabric using filament yarn is coated with an elastomer such as chloroprene rubber, chlorosulfonated olefin rubber, or silicone rubber, and the laminated base fabric is cut and sewn. Was there.

The high-pressure gas for inflating the air bag instantaneously is generally nitrogen gas, and this nitrogen gas instantaneously heats and generates sodium azide, which is a nitrogen gas generating agent, so that 500 is generated. It becomes a high temperature gas of about ℃. Therefore, on the face side, when this high-temperature nitrogen gas blows out through the airbag base fabric to the face, the face is burned. Therefore, a non-breathable base fabric is required so that such an accident does not occur.

On the other hand, the non-face side is generally provided with an exhaust hole called a vent hole in order to reduce the impact on the face when the face comes into contact with an airbag inflated with nitrogen gas. In an airbag with a vent hole, the same non-breathable base cloth coated with chloroprene rubber or silicone rubber was used for both the face side and non-face side, and the vent hole was provided in the non-face side base cloth. . However, the high-temperature nitrogen gas contains mist harmful to human body such as residual powder, and when the mist is discharged into the car through the vent hole, the air inside the car is polluted. there were. For this reason, there has been a demand for an airbag of a type in which a mist harmful to the human body such as residual explosives is filtered by the base cloth by using the base cloth having no vent hole and having high air permeability. For example, Jitsuko Sho 48-16
In Japanese Patent Publication No. 761 Gazette, an airbag that is inflated by a gas generated by an explosion of explosive is formed of a breathable cloth material, and a seat is formed on the occupant side cylindrical surface with a vertical line passing through the maximum width in the vertical direction at the time of the complete inflation. There has been proposed an airbag including a combination of a non-coated base fabric provided with a non-breathable material and a coated base fabric. The airbag is preferable in terms of reducing pollution of air inside the vehicle due to mist,
Since the coated base cloth is heavy and thick, it has a large impact force, and it has a drawback that it causes a large amount of shake of the handle and, in addition, it is an expensive airbag due to the coating process. .

In order to solve these drawbacks, Japanese Patent Laid-Open No. 4-228339 discloses a gas bag for an air bag system, which is made of a synthetic resin yarn, preferably a woven fabric of polyamide type, which is finished by plain weaving. The lower part of the gas bag has 16 to 23 yarns / cm, and the yarn of the woven fabric is 47
A gas bag (airbag) has been proposed in which the yarn is 0 dtex or less, and the yarn of the woven fabric is a low-shrinkable yarn in the lower part of the gas bag and an extensible yarn in the upper part of the gas bag.
The gas bag is an air bag in which non-coated base fabrics having different characteristics are combined, and is exhausted from the lower part of the gas bag made of a woven fabric finished with a plain weave of 16 to 23 pieces / cm, and is a mist harmful to the human body such as explosive residue. It is intended to be filtered with a base cloth, but it has a plain weave structure and a weave density of 16
The number of lines / cm is very likely to cause misalignment, the breathability becomes too high, and the burst pressure becomes low when the airbag is inflated. On the other hand, a high-density fabric having a weaving density of about 23 yarns / cm is less likely to cause misalignment, but has a drawback that it lacks in exhaust action because of its low air permeability. On the other hand, when the weaving density is more than 16 / cm and less than 23 / cm, there is a drawback that a well-balanced exhaust function and misalignment cannot be obtained.

[0006]

In view of the above situation, the present invention has a well-balanced reliability in which a high exhaust action and a high burst pressure are achieved by combining non-coated base fabrics having different characteristics. The purpose is to provide a high-quality airbag.

[0007]

The present invention has the following constitution in order to achieve the above object. That is, the airbag of the present invention is a non-coated airbag made of synthetic fiber cloth, wherein the cloth is a combination of a plain weave base cloth and a ripstop weave cloth, and the plain weave base cloth is used for the face side of the airbag. In addition, the base fabric of the ripstop structure is used on the non-face side.

[0008]

The present invention has been devised for using a plain weave fabric having optimum characteristics as an air bag base cloth on both the face side and the non-face side, and particularly, the non-face side base cloth. As a result, when a plain weave design which is excellent in breathability and exhaustability and which does not reduce the burst pressure is earnestly studied, a plain weave design having a ripstop design is reached. It has been clarified that the plain weave woven fabric exhibits the characteristic of maintaining the target burst pressure even though the woven fabric has a texture density having excellent breathability and exhaustability. That is, the present inventors have completed the present invention by clarifying that the degree of preventing the misalignment phenomenon is greatly related to the degree of preventing the decrease of the burst pressure.

The synthetic fiber in the present invention is not particularly limited as long as it satisfies the properties required as a base fabric for an air bag, for example, nylon 6, nylon 6.6, nylon 12, nylon 4 , Nylon 4.6
Fibers made of polyamide resin such as nylon 6 and nylon 6.6 polymer, nylon copolymerized with polyalkylene glycol, dicarboxylic acid and amines, homopolyester such as polyethylene terephthalate, repeating unit of polyester A fiber made of polyester resin such as a copolyester in which an aliphatic dicarboxylic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid or adipic acid is copolymerized in the acid component constituting paraffin, paraphenylene terephthalamide and an aromatic ether. Fibers made of aramid-based resin typified by the copolymers of, rayon fibers, ultra high molecular weight polyethylene fibers, paraphenylene sulfone,
Fiber made of sulfone resin such as polysulfone,
Fibers made of polyetherketone resin can be used. Among these fibers, polyamide resin fibers are particularly preferably used from the viewpoint of characteristics such as flexibility and impact resistance.

Each of the above-mentioned fibers may contain various additives which are usually used for improving the productivity or the characteristics in the manufacturing process or processing process of the raw yarn. For example, a heat stabilizer, an antioxidant, a light stabilizer, a leveling agent, an antistatic agent, a plasticizer, a thickener, a pigment, a flame retardant and the like can be contained.

The strength of the single fibers constituting the cloth is not particularly limited, but is preferably 6 g / denier or more, more preferably 7 g / denier or more. The fineness and the total fineness of the single fibers constituting the fabric are not particularly limited as long as they satisfy the mechanical properties required as an airbag, but the single yarn fineness is preferably 1 to 7 denier and the total fineness. Is preferably 200 to 1000 denier. Also,
It is further preferable that the yarn constituting the fabric contains a flame retardant compound.

The flame-retardant compound may be contained in the raw yarn manufacturing stage or the post-processing stage. As the flame retardant compound, a halogen compound, a platinum compound, copper oxide and titanium oxide are more preferable. Both filaments and staples can be used as the shape, but filaments are preferred from the viewpoint of mechanical characteristics.

The cloth in the present invention is a combination of plain weave and ripstop weaves. The ripstop design in the present invention is a warp and / or weft constituting a plain weave design, in which two or more yarns (ripstop yarns) are lined up at the time of weaving to form a ridge design, or before weaving. After preparing a yarn with a fineness larger than that of the ground yarn (ripstop yarn),
It means a woven woven fabric. In the present invention, since the flat fabric base fabric is used on the face side of the airbag, the air permeability of the flat fabric base fabric according to JIS L-1096 (6.27.1A method) is less than 0.8 cc / cm ² / sec. In order to form a base fabric having an air permeability of less than 0.8 cc / cm ² / sec, the cover factor represented by the sum of the square root of the warp fineness and the square root of the weft fineness is 2000 or more. Is preferred. On the other hand, the base fabric of the ripstop structure used for the non-face side has an exhaust action for mitigating the impact on the face when the face comes into contact with an airbag inflated with nitrogen gas, and JIS L -1096
The air permeability according to (6.27.1A method) is 0.8 cc / cm ² /
It is preferably sec or more. The air permeability depends on the fineness of the warp and weft to be used, the relative thickness of the ripstop yarn with respect to the base yarn, the ripstop pitch, and the cover factor, and therefore needs to be appropriately selected. The relative thickness of the ripstop yarn to obtain the base fabric with an air permeability of 0.8 cc / cm ² / sec or more is 1.2 times or more the thickness of the ripstop yarn Is preferable, and more preferably 1.5 to 3.0 times. If it exceeds 3.0 times, there is no problem in terms of air permeability,
Since the thickness of the rip stop portion is large, the storability as an airbag becomes poor, which is not preferable. Ripstop threads should be lined up more than once during weaving,
Alternatively, two or more yarns can be used by aligning the ground yarns in advance, or a yarn thicker than the ground yarns and not aligned can be used. In either method, the thickness of the ripstop yarn is It is preferable that the thickness is 1.2 times or more the thickness of the ground thread. Further, the rip stop yarn may be the same material as the ground thread, a different material from the ground thread, or a combination of the same material and different material. The ripstop pitch is preferably 2 to 20 mm and is set in relation to other factors related to air permeability. The rip stop may be in the vertical and horizontal directions of the woven fabric, only in the vertical direction, or only in the horizontal direction, but a rip stop in both the vertical and horizontal directions is particularly preferable in terms of isotropicity required for an airbag. The air bag of the present invention is an air bag made of non-coated base cloth not coated with resin and the like, and when the air bag is inflated, the plain woven base cloth used for the face side and the non-face side are used so that no misalignment occurs especially at the outer peripheral sewing portion. It is also important to use the ripstop fabric as a base fabric, and JIS L-10
It is preferably 30 kg or more in 96 (pin hooking method of 6.21.3), and the cover factor is preferably 2000 or more. Therefore, the cover factor of the ripstop textured base fabric is set to 2000 or more, and the thickness of the ripstop yarn and the ripstop pitch are adjusted so that the base fabric having the air permeability of 0.8 cc / cm ² / sec or more can be obtained. Is selected.

[0014]

EXAMPLES Next, the present invention will be described more specifically by way of examples. The weaving density, cover factor, air permeability, and misalignment of the airbag in the examples were measured by the following methods.

(Weave Density) The weave density was determined according to JIS L1096 6.6. (Cover factor) Calculated from the sum of the square root of the warp fineness and the square root of the weft fineness. (Air permeability) The air permeability was determined according to the air permeability measurement method of JIS L1096 6.27.1A. (Misalignment) JIS L1096 6.21.3 Measure the sliding resistance according to the pin hooking method in the vertical and horizontal directions,
The average value in the vertical and horizontal directions was obtained.

Examples 1, 2, and 3 Using nylon 6.6 filament yarn having a total fineness of 420 denier, 72 filaments and a strength of 9.0 g / denier, as warp and weft yarns as a base fabric for the face side of an airbag. A plain woven fabric having a density of 53 yarns / inch is used as the base fabric for the non-face side, the yarn is used as the base yarn, and two yarns that are the same as the base yarn are arranged as the rip stop yarns at the time of weaving and shown in Table 1. The woven fabric was arranged in the warp and weft directions at a pitch to obtain a woven fabric having a ripstop structure having a density of 55 warps / inch each. The evaluation results of the airbag are shown in Table 1. Examples 4, 5 and 6 Using the nylon 6.6 yarn of Example 1, a plain fabric having a density of each warp and weft of 53 yarns / inch was used as a base fabric for the face side of an airbag, for the non-face side. As the base fabric, the yarn is used as the base yarn, and as the rip stop yarn, two yarns that are the same as the base yarn are arranged at the time of weaving and are arranged only in the warp direction at the pitch shown in Table 1.
A woven fabric having a ripstop design having a density of 55 warps / inch each was obtained. The evaluation results of the airbag are shown in Table 1.

Example 7 Using the nylon 6.6 yarn of Example 1, as a base fabric for the face side of an airbag, a plain weave fabric having a density of 46 warps / inch each was used as a base fabric for the non-face side. As the cloth, the yarn is used as the ground yarn, and two yarns as the rip stop yarn, which are the same as the ground yarn, are lined up at the time of weaving, arranged at a warp direction of 5 mm pitch,
A woven fabric with a ripstop design having a density of 46 wefts / inch was obtained. The evaluation results of the airbag are shown in Table 1.

Example 8 Polyethylene terephthalate yarn having a total fineness of 420 denier, 144 filaments, and strength of 9.1 g / denier was used as a base fabric for the face side of an airbag, and each of warp and weft had a density of 55 yarns / inch. Using the plain weave as a base fabric for the non-face side, the yarn is used as the ground yarn, and two yarns that are the same as the ground yarn are arranged as rip stop yarns at the time of weaving and arranged at a pitch of 5 mm in the warp and weft directions. A woven fabric having a ripstop design having a density of 55 warps / inch each was obtained. The evaluation results of the airbag are shown in Table 1.

Comparative Example 1 A nylon 6.6 filament yarn having a total fineness of 420 denier, 72 filaments, and a strength of 9.0 g / denier was used as a base fabric for the face side of an airbag, each of warp and weft 55 / inch. A plain weave having a density of 5 was used as a non-face side base fabric to obtain a plain weave having a warp and weft density of 53 yarns / inch each. The evaluation results of the airbag are shown in Table 1. Comparative Example 2 A nylon 6.6 filament yarn having a total fineness of 420 denier, 72 filaments, and a strength of 9.0 g / denier was used as a base fabric for the face side of an airbag, and the density of each warp and weft was 55 / inch. Using the plain woven fabric as a base fabric for the non-face side, a plain woven fabric having a density of 46 warps / inch for each weft was obtained. The evaluation results of the airbag are shown in Table 1.

Comparative Example 3 A nylon 6.6 filament yarn having a total fineness of 420 denier, 72 filaments and a strength of 9.0 g / denier was used as the ground yarn, and the same yarn as the ground yarn was used as the rip stop yarn. 2 side by side during weaving, 1 in the warp and weft directions
A fabric having a ripstop design having a density of 55 wefts / inch each was obtained as a base fabric for the face side of the airbag, which was arranged at a pitch of 0 mm. As the base fabric for the non-face side, the yarn is used as the ground yarn, and two yarns that are the same as the ground yarn are arranged as rip stop yarns at the time of weaving and are arranged at a pitch of 5 mm in the warp and weft directions. As a base fabric for use, a woven fabric having a ripstop design having a density of 55 warps / inch each was obtained. The evaluation results of the airbag are shown in Table 1.

[0021]

[Table 1] As is clear from Table 1, the combinations of the plain weave fabrics of Comparative Examples 1 and 2 were well balanced in air permeability and misalignment required as the non-face side base fabric even when the weave density was changed. However, the combination of the woven fabrics having the ripstop design of Comparative Example 3 could not obtain the fabric with low air permeability required as the face side base fabric. All of the products of the present invention have a good balance of air permeability and misalignment required as an airbag, and particularly, those of Examples 1, 2, 3, 4, 5, 8 are the face side base fabrics. And the non-facial base fabric has a sliding resistance of 30 kg or more, and the face side base fabric has an air permeability of 0.8.
Less than cc / cm ² / sec, non-face side base fabric has air permeability of 0.8
The cc / cm ² / sec or more was preferable as an airbag.

[0022]

According to the present invention, it is possible to reduce the contamination of the interior of an automobile due to the residual explosive powder, and to prevent burns due to high-temperature nitrogen gas. In addition, it is well balanced in terms of both exhaust action and misalignment, and the fabric with a ripstop structure used for the non-face side base fabric has an extremely high anti-misalignment function and a high tear strength, so a high burst It is possible to provide a highly reliable airbag in which pressure is obtained, there is little misalignment of the seam portion during weaving, and the airbag is inflated smoothly. Further, since it is a non-coated airbag, it is possible to provide an airbag superior in productivity and cost.

Claims (4)

[Claims] 1. A non-coated airbag made of synthetic fiber cloth, wherein the cloth is made of a combination of a plain weave base cloth and a ripstop weave cloth, and the plain weave base cloth is placed on the face side of the airbag with a ripstop. An airbag characterized by using a tissue base cloth on the non-facial side. Wherein the air permeability of the base fabric of plain weave organization 0.8 cc / cm ²
The air bag according to claim 1, wherein the air permeability of the base fabric having a ripstop structure is 0.8 cc / cm ² / sec or more. 3. The airbag according to claim 1, wherein the base fabric having a plain weave design and the base fabric having a ripstop design have a cover factor of 2000 or more. 4. The airbag according to claim 1, wherein the plain weave fabric and the ripstop fabric have a sliding resistance of 30 kg or more.