JPH08188107A - Manufacture of foundation cloth for air bag - Google Patents

Abstract

PURPOSE: To secure a non-coat air bag that is inherent in low permeability and excellent in pliableness and storability as keeping a necessary mechanical characteristic by applying steaming treatment to an air bag foundation cloth consisting of a synthetic fiber fabric. CONSTITUTION: When such one as subjected to steaming treatment is adopted to a synthetic fiber fabric forming an air bag foundation cloth, especially a non-coat air bag foundation cloth, restraint between those of single yarn and yarn filament of the fabric becomes lessened, given a puff, and further, since an interstitial part is phenomenized, such an effect that low permeability is improved as keeping a mechanical characteristic is securable. As for the synthetic fiber, nylon 6.6 or the like is used. As for fabric structure, a plain weave fabric is desirable for its excellent mechanical characteristics from the standpoint of thin cloth surface. On the other hand, as to steaming treatment, a batch method in which synthetic fiber fabric is treated in steam for a specified time, is applied. Owing to such like characteristics, an occupant protection system by an air bag is thus spreadable.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an airbag for absorbing and protecting an occupant's impact during a vehicle collision, and more particularly to an airbag base having excellent low air permeability and flexibility. The present invention relates to a method for manufacturing a cloth, particularly a base cloth for a non-coated airbag.

[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 an automobile collision, the sensor operates in response to the impact of a collision to generate high-temperature and high-pressure gas, which causes the airbag to inflate momentarily, causing the occupant's face and front to collide during a collision. It is intended to protect the head.
Conventionally, a plain woven fabric using nylon 66 or nylon 6 filament yarn of 300 to 1000 denier is used for an air bag to improve heat resistance, flame retardancy, air barrier property, etc.
It was made by applying an elastomer resin such as chloroprene, chlorosulfonated olefin, and synthetic rubber such as silicone, cutting the laminated base cloth, and sewing it into a bag.

However, when applying and laminating these elastomer resins on one side of a base cloth, a coating method such as knife coating, roll coating and reverse coating is generally adopted. With respect to the base cloth, in the case of a chloroprene elastomer resin, it is usually 90 to 120 on the surface of the base cloth.
It was not preferable because it was applied g / m ² and was considerably heavy, the texture was rough and hard, and when the air bag was inflated, it could be scratched if it came into contact with the face. In addition, there is a problem that it is difficult to fold in terms of storability.
Further, in the case of a silicone elastomer resin having more excellent heat resistance and cold resistance as compared with the chloroprene elastomer resin, the coating amount is 40 to 60 g / m ² and the weight is reduced,
Although it has improved considerably in terms of texture and storability, it is still not enough. Further, when coating these elastomeric resins, the processing steps are very complicated, which is not a preferable method in terms of process control and processing costs.

On the other hand, in order to improve the above-mentioned drawbacks, non-coated airbags by increasing the density of polyamide fiber such as nylon 66 and nylon 6 and polyester fiber woven fabric are being studied, and their weight and flexibility have been considerably improved. However, the most necessary low air permeability of the airbag is not sufficient, and a satisfactory airbag base fabric has not been obtained.

[0005]

SUMMARY OF THE INVENTION In view of the above-mentioned conventional drawbacks, the present invention has a low air permeability while maintaining the necessary mechanical properties as an airbag, and is flexible and excellent in storability. In particular, it is intended to provide a non-coto airbag.

[0006]

In order to achieve the above object, the present invention has the following constitution. That is, the method for producing a base fabric for an air bag of the present invention is characterized by subjecting the synthetic fiber woven fabric constituting the base fabric to steam heat treatment.

[0007]

According to the present invention, when a steam-heat treated fabric is used as a synthetic fiber woven fabric constituting an air bag base fabric, particularly a non-coated air bag base fabric, such a woven fabric is restrained between single yarns and yarns. It has been clarified that the effect of improving low air permeability is maintained while maintaining the mechanical properties, since it is softened, bulges are given, and the gap is reduced.

As the synthetic fiber woven fabric in the present invention, nylon 6.6, nylon 6, nylon 12, nylon 4
.6, and a copolymer of nylon 6 and nylon 6.6,
Polyamide glycol, polycarboxylic acid such as dicarboxylic acid or amine copolymerized with nylon, homopolyester such as polyethylene terephthalate and polybutylene terephthalate, isophthalic acid, 5-sodium sulfoisophthalic acid or adipine as the acid component constituting the repeating unit of polyester Consists of polyester fiber copolymerized with aliphatic dicarboxylic acid such as acid, aramid fiber represented by copolymerization with para-phenylene terephthalamide and aromatic ether, rayon fiber, sulfone fiber, ultra high molecular weight polyethylene fiber, etc. Synthetic fiber fabric is used. Further, a synthetic fiber woven fabric composed of polymer array fibers having a sea-island structure mainly composed of the above synthetic fibers is also used. Among these, a synthetic fiber woven fabric composed of nylon 6.6, nylon 6 fibers and polyester fibers is particularly preferable. Such fibers may contain various additives that are usually used for improving the productivity or the characteristics in the manufacturing process or processing process of the raw yarn. For example, thermal stability, antioxidants,
A light stabilizer, a leveling agent, an antistatic agent, a plasticizer, a thickener, a pigment, a flame retardant, etc. can be contained.

The structure of the woven fabric is plain weave, twill weave,
Textiles such as satin weave and their modified weaves and multiaxial weaves are used, and among these, plain weaves are particularly preferable because of their excellent mechanical properties and thinness. The strength of the single fiber constituting the woven fabric is not particularly limited, but is preferably 5 g / denier or more, more preferably 7 g / denier or more.
g / denier or more, and the fineness and total fineness of the single fibers constituting the woven fabric are not particularly limited as long as they satisfy the mechanical properties required as a non-coated airbag, but the single yarn fineness is preferable. Is 0.01 to 7 denier, and the total fineness is 200 to 1000 denier.
As a woven fabric, a cover factor of 1800 or more is preferable from the viewpoint of low air permeability, that is, airtightness, a tear strength of 10 kgf or more, a basis weight of 250 g / m ² or less, a thickness of 0.4 mm or less, and a tensile strength of 180 kgf. / 3 cm
As described above, a breaking elongation of 15% or more is preferably used from the viewpoint of mechanical properties, flexibility and storability required for a non-coated airbag. Here, the cover factor is D1 for the total warp yarn fineness, N1 for the warp yarn density, and D for the total weft yarn fineness.
2, and the warp density is N2, (D1) ^1/2 × N1 + (D
2) It is represented by ^1/2 x N2. A water jet loom, an air jet loom, and a rapier loom are preferable as the loom used in the weaving process.

On the other hand, as the steam heat treatment of the present invention, a steam heat treatment by a batch system in which a synthetic fiber fabric is treated in steam for a certain period of time, or a continuous system in which steam is passed at a constant rate, or a combination of dry heat and steam Steaming heat treatment by etc. is applied. Further, a so-called steaming process in which a synthetic fiber woven fabric is sandwiched between a steam drum wound around a felt and an endless felt and steam-heat treated is also applicable. By performing such a steam heat treatment, it becomes possible to impart flexibility and low air permeability.

The steam heat treatment is carried out at the stage of greige after weaving,
After scouring and drying, it may be applied at any stage after heat setting, but it is more effective when applied after heat setting. If necessary, chemical or physical treatment may be performed, and then steaming heat treatment may also be effective.

[0012]

EXAMPLES The present invention will be described in more detail with reference to examples. The low air permeability, flexibility, and storability of the airbag base fabric in the examples were measured by the following methods.

Air permeability: JIS L1096.6.
It was measured according to the 27.1 A Frajure method.

Flexibility: The bending hardness in the warp and weft directions was measured with a KES-FB pure bending tester, and the mean value of the warp and the weft was shown.

Storability: A 10 cm × 20 cm woven fabric is bent into a tubular shape, and the bulkiness when a load of 15 g is applied is measured. As a standard product, silicone rubber coated product (4
5g / m ² coated product)
It was shown as a relative value.

Example 1 Total fineness 420 denier, 72 filaments, strength 9.7
Using a filament yarn of nylon 6.6 fiber having a g / denier and an elongation of 24%, a plain woven fabric having both warp and weft of 50 yarns / inch was woven with a water jet loom. Next, the woven fabric was scoured and dried by a usual method, and then heat set at 180 ° C. for 30 seconds. Then, after passing through steam in a continuous steamer at 105 ° C for 2 minutes, 100 ° C
And dried for 3 minutes to obtain a base fabric for non-coated airbag.

The characteristics of the non-coated airbag base fabric thus obtained were evaluated and are shown in Table 1. The base fabric for a non-coated airbag of the present invention was excellent in flexibility, storability and low air permeability.

Comparative Examples 1 and 2 Total fineness 420 denier, 72 filaments, strength 9.7
Using a filament yarn of nylon 6.6 fiber having a g / denier and an elongation of 24%, a plain woven fabric having both warp and weft of 50 yarns / inch was woven with a water jet loom. Next, the woven fabric was scoured and dried by an ordinary method, and then heat set at 180 ° C. for 30 seconds to obtain a non-coated airbag base fabric [Comparative Example 1]. On the other hand, total fineness of 420 denier, 7
2 filaments, strength 9.7g / denier, elongation 24%
After weaving a plain weave of 45 / inch both warp and weft with a water jet loom using filament yarn of Nylon 6.6 fiber of No. 6, after scouring and drying by a usual method,
Heat set at 180 ° C. for 30 seconds. Then, using a comma coater, the woven fabric was coated twice with chloroprene rubber so that the coating amount was 90 g, 1
Vulcanization was performed at 80 ° C. for 3 minutes to obtain a chloroprene rubber-coated base fabric for airbags [Comparative Example 2].

The characteristics of the thus obtained non-coated base fabric for airbag were evaluated in the same manner as in Example 1 and shown in Table 1. As can be seen from this, the non-coated airbag base fabric of Comparative Example 1 was excellent in flexibility and storability,
It was inferior in low air permeability. Further, the silicone rubber-coated airbag base fabric of Comparative Example 2 was excellent in low air permeability, but was inferior in flexibility and storability, and the processing step was complicated and there was a problem in productivity.

Example 2 Total fineness 420 denier, 110 filaments, strength 8.
Using a filament yarn of nylon 6 fiber having a denier of 7 g / denier and an elongation of 22%, a plain woven fabric having a warp and a weft of 52 yarns / inch was woven with an air jet loom. Next, the woven fabric was scoured and dried by a usual method, and then heat set at 180 ° C. for 30 seconds. Then, in a continuous steaming apparatus, the fabric is sandwiched between a steam drum wound around a felt and an endless felt, subjected to steam heat treatment at 105 ° C. for 2 minutes, and then cooled to obtain a base fabric for an uncoated airbag. It was

The characteristics of the thus obtained non-coated base fabric for airbag were evaluated in the same manner as in Example 1 and shown in Table 1. The base fabric for a non-coated airbag of the present invention was excellent in flexibility, storability and low air permeability.

Comparative Examples 3 and 4 Total fineness 420 denier, 110 filaments, strength 8.
Using a filament yarn of nylon 6 fiber having a denier of 7 g / denier and an elongation of 22%, a plain woven fabric having a warp and a weft of 52 yarns / inch was woven with an air jet loom. Next, the woven fabric was scoured and dried by a usual method, and then heat set at 180 ° C. for 30 seconds to obtain a base fabric for non-coated airbag [Comparative Example 3]. On the other hand, using a filament yarn of nylon 6 fiber having a total fineness of 420 denier, 110 filaments, a strength of 8.7 g / denier, and an elongation of 22%, a plain woven fabric having both warp and weft of 45 yarns / inch is woven with an air jet loom. After scouring and drying in the usual way, 3 at 180 ° C
Heat set for 0 seconds. Thereafter, the woven fabric was coated with a methyl vinyl silicone rubber using a comma coater so that the coating amount was 45 g, and the temperature was 180 ° C.
Was vulcanized for 3 minutes to obtain a silicone rubber-coated base fabric for airbags [Comparative Example 4].

The characteristics of the non-coated airbag base fabric thus obtained were evaluated in the same manner as in Example 1 and shown in Table 1. As can be seen from the above, the non-coated airbag base fabric of Comparative Example 3 was excellent in flexibility and storability,
It was inferior in low air permeability. In addition, the silicone rubber-coated airbag base fabric of Comparative Example 4 was excellent in low air permeability, but was inferior in coarseness and hardness, flexibility and storability, and the processing step was complicated and there was a problem in productivity. It was

Example 3 Total fineness 500 denier, 144 filaments, strength 8.
Using a filament yarn of polyester fiber having 5 g / denier and an elongation of 18%, a plain woven fabric having a warp yarn of 62 yarns / inch and a weft yarn of 48 yarns / inch was woven using a rapier loom. Then, the woven fabric is scoured and dried by a usual method, and then the woven fabric is dried at 180 ° C. for 3 days.
Heat set for 0 seconds. Then, in a continuous steaming apparatus, the fabric is sandwiched between a steam drum wound around a felt and an endless felt, subjected to steam heat treatment at 105 ° C. for 2 minutes, and then cooled to obtain a base fabric for an uncoated airbag. It was

The characteristics of the thus obtained non-coated base fabric for airbag were evaluated in the same manner as in Example 1 and shown in Table 1. The base fabric for a non-coated airbag of the present invention was excellent in flexibility, storability and low air permeability.

Comparative Examples 5 and 6 Total fineness 500 denier, 144 filaments, strength 8.
Using a filament yarn of polyester fiber having 5 g / denier and an elongation of 18%, a plain woven fabric having a warp yarn of 62 yarns / inch and a weft yarn of 48 yarns / inch was woven using a rapier loom. Then, the woven fabric is scoured and dried by a usual method, and then the woven fabric is dried at 180 ° C. for 3 days.
The base fabric for non-coated airbag was obtained by heat setting for 0 seconds [Comparative Example 5]. On the other hand, heat-set the product at 150 ° C
Both sides were pressure-compressed at a pressure of 30 tons and a speed of 15 m / min between a metal roll having a flat surface and a normal temperature plastic heated to obtain a base fabric for a non-coated airbag [Comparative Example 6].

The characteristics of the thus obtained non-coated base fabric for airbag were evaluated in the same manner as in Example 1 and shown in Table 1. The base fabric for a non-coated airbag of Comparative Example 5 was inferior in low air permeability, and the base fabric for a non-coated airbag in Comparative Example 5 was excellent in low air permeability, but was inferior in storability.

Example 4 Polyethylene terephthalate copolymerized with 5-sodium sulfoisophthalic acid as an island component and having a sea-island structure having a total fineness of 470 denier, 60 filaments and a strength of 8.2.
Using a filament yarn of polyethylene terephthalate fiber with g / denier and elongation of 16%, weave a plain weave fabric with warp and weft woven densities of 55 yarns / inch in an air jet loom and heat at 180 ° C for 30 seconds. Set Thereafter, the woven fabric was desalted with a 1.5% aqueous sodium hydroxide solution at 100 ° C. for 30 minutes and dried. The woven fabric was a high-density woven fabric having a total fineness of 420 denier and a fineness of 960 filaments. Then, after being treated with a continuous HT steamer device at 160 ° C. for 2 minutes, it was dried at 80 ° C. for 2 minutes to obtain a non-coated airbag base fabric.

The characteristics of the thus obtained non-coated base fabric for airbag were evaluated in the same manner as in Example 1 and shown in Table 1. The base fabric for a non-coated airbag of the present invention had low air permeability, and was excellent in flexibility and storability.

Comparative Example 7 Using a filament yarn of polyethylene terephthalate fiber having a total fineness of 470 denier having a sea-island structure, 60 filaments, a strength of 8.2 g / denier and an elongation of 16%, weaving density of warp and weft in an air jet loom. Was woven with a flat design of 55 filaments / inch and heat set at 180 ° C. for 30 seconds. Thereafter, the woven fabric was deseaed with a 1.5% aqueous sodium hydroxide solution at 100 ° C. for 30 minutes and dried to obtain a base fabric for a non-coated airbag.

The characteristics of the thus obtained non-coated base fabric for airbag were evaluated in the same manner as in Example 1 and shown in Table 1. The base fabric for a non-coated airbag of Comparative Example 7 was excellent in flexibility and storability, but was inferior in low air permeability.

[0032]

[Table 1]

[0033]

EFFECTS OF THE INVENTION According to the present invention, a base fabric for an air bag, which has low air permeability, is flexible and has excellent storability while maintaining the necessary mechanical strength as an air bag, especially for a non-coated air bag. Since the base cloth can be provided, an occupant protection system using an airbag can be popularized.

Claims (7)

[Claims] 1. A method for manufacturing an air bag base cloth, comprising: a base cloth for an air bag made of a synthetic fiber woven fabric, wherein the base cloth is subjected to steaming heat treatment. 2. The method for producing an airbag base fabric according to claim 1, wherein the steam heat treatment is performed after heat setting. 3. The method for manufacturing an airbag base fabric according to claim 1, wherein the steaming heat treatment is performed by sandwiching the base fabric between a steam drum wound around felt and an endless felt. 4. The method for producing a base fabric for an air bag according to claim 1, wherein the fabric constituting the synthetic fiber fabric has a cover factor of 1800 or more. 5. The method for producing an airbag base fabric according to claim 1, wherein the synthetic fiber woven fabric is N6 · 6 or N6 fiber. 6. The method for producing a base fabric for an air bag according to claim 1, wherein the synthetic fiber woven fabric is a polyester fiber. 7. The method for producing a base fabric for an air bag according to claim 1, wherein the air bag is a non-coated air bag.