JPH07186859A - Manufacture of base cloth for air bag - Google Patents

Abstract

PURPOSE:To provide a low permeability base cloth for an air bag which is prevented from the occurrence of a fray during a cutting work and light and excellent in containing ability as mechanical characteristics necessary as an air bag are held. CONSTITUTION:A manufacturing method for a base cloth for an air bag is such that, in an air bag formed of a synthetic resin cloth, impregnation treatment is applied on the cloth by using at least one kind of resin dilution solution selected from synthetic resin consisting of a polyamide, a polyester, a polyurethane, a resorcinol formalin, an acryl, a styrenebutadien, and a nitrile butadien system.

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 in the event of a vehicle collision, and more specifically, it is lightweight, has a soft texture, and has an excellent anti-raveling property. The present invention relates to a low-ventilation 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 case of a collision accident of an automobile, an airbag receives a collision impact and a sensor is activated to generate high temperature and high pressure gas, and the gas causes the airbag to inflate instantaneously, the occupant's face at the time of collision, It is intended to protect the forehead.

Conventionally, an air bag is made of a plain woven fabric using nylon 66 or nylon 6 filament yarn of 300 to 1000 denier and chloroprene or chlorosulfonated olefin for improving heat resistance, flame retardancy and air barrier property. It was made by applying an elastomer resin such as a synthetic rubber such as silicone, cutting the laminated base cloth, and sewing it into a bag.

However, when these elastomer resins are applied and laminated 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,
It has improved considerably in terms of texture and storability, but it is still not enough.

On the other hand, in the air bag base cloth, the weight reduction and the storability of the air bag have been strongly demanded in order to reduce the weight and size of the air bag device.
Further, as the performance of the inflator is improved, the temperature of the reaction gas is being lowered, and an airbag using a non-coated base fabric has been attracting attention. So nylon 66,
Non-coated airbags made of polyamide fiber woven fabrics such as nylon 6 and polyester fiber woven fabrics are being studied, and mechanical properties, low air permeability, as air bag base fabrics,
The storability has improved compared to the coated base fabric, but it is not yet satisfactory, and there is a problem of fraying during the cutting process, which is peculiar to the non-coated base fabric, and loosening of the yarn, and it is a satisfactory airbag base. The current situation is that no cloth has been obtained.

[0006]

SUMMARY OF THE INVENTION In view of the drawbacks of the conventional airbags, an object of the present invention is to keep the mechanical properties required as an airbag, to prevent fraying during cutting, to be lightweight and storable. It is intended to provide an air bag base fabric having excellent low air permeability.

[0007]

In order to achieve the above object, the present invention has the following constitution.

That is, in an airbag made of a synthetic fiber cloth, the cloth is made of polyamide type, polyester type,
Method for manufacturing an airbag base fabric, characterized by impregnating with at least one resin diluent selected from synthetic resins consisting of polyurethane, resorcinol formalin, acrylic, styrene butadiene and nitrile butadiene .

[0009]

The present invention is basically based on impregnating a synthetic fiber cloth constituting an airbag base cloth with a synthetic resin, and the present invention cannot be achieved without this. That is, when the method of the present invention is adopted, it is possible to provide a low-ventilation air bag base fabric that retains the mechanical properties required as an air bag, does not fray during cutting, is lightweight, and has excellent storability. Is something that can be done.

The synthetic fiber cloth referred to in the present invention includes nylon 6.6, nylon 6, nylon 12, nylon 4
6 and nylon 6 and nylon 6/6 copolymer, polyamide fiber obtained by copolymerizing nylon 6 with polyalkylene glycol, dicarboxylic acid and amines, homopolyester such as polyethylene terephthalate, and an acid component constituting the repeating unit of polyester. Polyester fiber copolymerized with aliphatic dicarboxylic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid or adipic acid, aramid fiber typified by copolymerization with paraphenylene terephthalamide and aromatic ether, rayon fiber, super Knitted fabric and non-woven fabric formed from continuous fibers such as high molecular weight polyethylene fibers, sulfone fibers such as paraphenylene sulfone and polysulfone, polyetherketone fibers, carbon fibers and glass fibers, but are not particularly limited. , Plain weave fabric from the land Susuki surface is preferable. Among these fibers, a plain woven fabric made of polyamide fiber and polyester fiber has excellent airbag characteristics.

The continuous fiber may contain various additives which are usually used for improving the productivity or the characteristics in the manufacturing process and the processing process of the raw yarn. For example, thermal stability, antioxidant, light stabilizer, leveling agent, antistatic agent, plasticizer, thickener, pigment, flame retardant and the like may be contained.

The strength of the single fibers constituting the woven fabric is not particularly limited, but is preferably 6 g / denier, more preferably 7 g / denier or more. The fineness of the single fibers constituting the woven fabric and the total fineness are not particularly limited as long as they satisfy the required mechanical properties as an airbag, but the single yarn fineness is preferably 2 to 8 denier, The total fineness is preferably 200 to 600 denier. Also, the cover factor of the fabric is 1500
It is more preferably ˜2500.

The synthetic resin referred to in the present invention is a polyamide resin, a polyester resin, a polyurethane resin, an acrylic resin, a resorcinol formalin resin, an acrylic resin, a styrene butadiene resin, a nitrile butadiene resin, which is necessary. A filler, a cross-linking agent, a heat anti-aging agent and the like can be contained as required. These synthetic resins may be used alone or in combination of two or more. Among these, polyamide resin made of water-soluble nylon, polyester resin made of water-soluble polyethylene terephthalate, self-emulsifying urethane resin made of oligomer polyol and polyisocyanate, acrylic rubber made of acrylate ester, and resorcin formalin resin and styrene. A mixed resin combined with butadiene rubber is effective. Among these synthetic resins, those having a glass transition point of -10 ° C or lower are more preferable in terms of softness.

The diluting solution of the synthetic resin may be an aqueous system which is emulsified and dispersed in water, or a solvent system which is dissolved in an organic solvent, but an aqueous system is preferred from the viewpoint of equipment for impregnation treatment, workability and cost. . Of course, an aqueous diluent such as a water-soluble nylon resin in which the resin itself is water-soluble is more preferable in terms of workability. As the concentration of the resin diluent,
Although not particularly limited, the solid content is usually 0.05 to 5.
It is preferable that it contains 100% by weight. If necessary, a flame retardant compound containing a halogen compound, a phosphorus compound and a sulfur-containing nitrogen compound may be added to the resin diluent.
As the method of impregnation, for example, a device to be immersed and a mangle for uniform inclusion or a device including vacuum can be applied, but the method is not particularly limited. The impregnation treatment can be performed immediately after scouring, after drying, or after heat setting.

[0015]

EXAMPLES The present invention will be described in more detail with reference to examples. The mass of the airbag in the examples, the bending resistance,
The air permeability, storability, anti-raveling property, expansion and development time, and burst pressure were measured by the following methods.

Mass: Determined by the mass measurement method of JIS K6328. Hardness: Determined by the cantilever method of JIS L1096. Air permeability: Using a laminar flow tube air permeability meter, the fluid (air) was adjusted to a pressure of 0.2 kg / cm ² and allowed to flow, and the air flow rate (cc / cm ² / sec) passing at that time was measured. Storability: 1 cm by bending a 10 cm x 20 cm fabric into a cylinder
The bulkiness when a load of 5 g is applied is measured. As a standard product, the relative value is shown when the bulkiness of the silicone rubber coated product (45 g / m ² coated product) is 100. Flame retardance: The burning rate (mm / min) was determined based on the FMVSS302 method (horizontal method).

Anti-fraying property: A woven fabric cut into a circular shape having a diameter of 20 cm was put in a drum type rotating machine and rotated at 50 ° C. for 15 minutes, and the degree of fraying was expressed by a grade. (Evaluation Criteria) Grade 5: No fraying Grade 3: Fraying can be seen Grade 1: Fraying is noticeable (2nd and 4th grades show the degree of fraying between each) Inflation deployment time: airbag dynamic Using a burst tester, 30
The inflation and deployment time of the L-capacity airbag bag was measured. Burst pressure: 30L using an airbag dynamic burst tester
The burst pressure of the airbag body of the volume was measured.

Examples 1 and 2 Total fineness 420 denier, 72 filaments, strength 9.8
Using a filament yarn of nylon 6.6 fiber having a g / denier of 24% and an elongation of 24%, a woven fabric having a flat design in which the weaving densities of the warp and the weft were both 52 / inch was obtained. Next, the woven fabric was scoured, dried and heat set by a conventional method. Thereafter, the woven fabric was adjusted to 0.3 wt% [Example 1] and 1.0 wt% [Example 2] of AQ nylon P-70 (water-soluble nylon resin, manufactured by Toray Industries, Inc.) in terms of solid content. It was dipped in the diluted resin solution and squeezed with a mangle under 3 kg / cm ² . Then
It heat-processed at 160 degreeC for 1 minute, and obtained the base fabric for airbags. The properties of the air bag base fabric thus obtained are shown in Table 1. The airbag base fabric of the present invention was free from fraying during the cutting process and free from the looseness of the yarns, low air permeability and storability as an airbag were obtained, and the burst pressure and the inflation time were good.

Comparative Examples 1 and 2 Total fineness 420 denier, 72 filaments, strength 9.8
Using a filament yarn of nylon 6.6 fiber having a g / denier of 24% and an elongation of 24%, a woven fabric having a flat design in which the weaving densities of the warp and the weft were both 52 / inch was obtained. Next, the woven fabric was scoured, dried and heat set by a usual method to obtain a base fabric for an airbag [Comparative Example 1]. The same woven fabric was dipped in a resin diluting solution in which an amino-modified silicone resin was adjusted to a solid content of 1.0% by weight and squeezed with a mangle under 3 kg / cm ² . Then, heat treatment was performed at 160 ° C. for 1 minute to obtain a base fabric for airbag [Comparative Example 2].

The characteristics of the air bag base fabric thus obtained were evaluated in the same manner as in Example 1 and shown in Table 1. Table 1
As can be seen from the above, the airbag base fabric of Comparative Example 1 is
When the cutting process was performed, fraying occurred and the yarns were separated, resulting in poor workability and a problem. Further, although the airbag base fabric of Comparative Example 2 was excellent in storability as an airbag, there was a problem in that the fabric was significantly frayed during the cutting process, the yarns were separated, and the workability was poor.

Examples 3, 4 Total fineness 420 denier, 110 filaments, strength 9.
5 g / denier, 22% elongation 22% nylon 6.6 fiber filament yarn is used, and the warp and weft woven densities are both 55
A woven fabric having a flat design of books / inch was obtained. Next, the woven fabric was scoured, dried and heat set by a conventional method. Thereafter, the woven fabric was treated with Nipol LX874 (acrylic acid ester resin, manufactured by Nippon Zeon Co., Ltd.) in a solid content of 1.5% by weight.
[Example 3], and Nipol LX874 (acrylic acid ester-based resin, manufactured by Nippon Zeon Co., Ltd.) in solid content of 5.0% by weight, Vigol NS (guanyl sulfamide-based flame retardant compound, Daikyo Chemical Co., Ltd.) Was manufactured by immersing it in a resin diluting solution adjusted to 3.0% by weight in solid content [Example 4] and squeezing it with a mangle under 3 kg / cm ² . Then 1
It heat-processed at 60 degreeC for 1 minute, and obtained the base fabric for airbags.

Comparative Examples 3 and 4 Total fineness 420 denier, 110 filaments, strength 9.
5g / denier, 22% elongation 22% nylon 6.6 fiber filament yarn, both warp and weft woven densities are 48
A woven fabric having a flat design of books / inch was obtained. Next, the woven fabric was scoured, dried and heat set by a conventional method. Thereafter, the woven fabric was coated with a silicone rubber using a comma coater to a coating amount of 45 g / m ² and 180 ° C.
Was vulcanized for 2 minutes to obtain an air bag base fabric [Comparative Example 3]. Further, with respect to the woven fabric not impregnated with the above synthetic resin, a base fabric for an air bag was similarly prepared [Comparative Example 4].

The characteristics of the air bag base fabric thus obtained are shown in Table 1. The airbag base fabric of the present invention was free from fraying during the cutting process and free from the looseness of the yarns, low air permeability and storability as an airbag were obtained, and the burst pressure and the inflation time were good. on the other hand,
The airbag base fabric of Comparative Example 3 suffered from fraying at the time of cutting, and the yarns were scattered, resulting in a poor workability and a problem.
The airbag base fabric of Comparative Example 4 has no fraying during the cutting process, but the coating process is complicated and the cost is high.
There was also a problem with storability.

Examples 5, 6 and Comparative Examples 5, 6 Total fineness 420 denier, 72 filaments, strength 9.7
Using nylon 6 fiber filament yarn having g / denier and elongation of 21%, and polyethylene terephthalate fiber filament yarn having total fineness of 420 denier, 144 filament, strength of 9.5 g / denier and elongation of 20%, warp and weft A woven fabric having a flat design having a weave density of 51 yarns / inch was obtained. Next, the woven fabric was scoured, dried and heat set by a conventional method. Thereafter, the fabric is softtex U-10.
0 (water-soluble polyurethane resin, manufactured by Kao Soap Co., Ltd.) was dipped in a resin diluting solution adjusted to a solid content of 1.2% by weight,
It was squeezed with a mangle under 2.5 kg / cm ² . Then 1
It heat-processed at 70 degreeC for 1 minute, and obtained the base fabric for airbags [Examples 5 and 6]. In addition, as comparative examples, with respect to the woven fabric not impregnated with the above synthetic resin, air bag base fabrics were similarly prepared [Comparative Examples 5 and 6].

The characteristics of the air bag base fabric thus obtained are shown in Table 1. The airbag base fabric of the present invention was free from fraying during the cutting process and free from the looseness of the yarns, low air permeability and storability as an airbag were obtained, and the burst pressure and the inflation time were good. on the other hand,
The airbag base fabrics of Comparative Example 5 and Comparative Example 6 suffered from fraying at the time of cutting, and the yarns were scattered, resulting in poor workability.

Example 7, Comparative Example 7 Total fineness 420 denier, 192 filaments, strength 9.
Using a filament yarn of polyethylene terephthalate fiber having a denier of 2 g / denier and a elongation of 21%, a woven fabric having a flat design in which the weaving densities of the warp and the weft were both 48 / inch was obtained. Next, the woven fabric was scoured, dried and heat set by a conventional method.

Thereafter, the woven fabric was mixed with resorcin formalin resin having a molar ratio of resorcin and formalin of 1 / 1.25 in solid content of 0.2% by weight and Nipol L.
X110 (styrene butadiene resin, manufactured by Nippon Zeon Co., Ltd.) was dipped in a resin diluting solution adjusted to a solid content of 1.0% by weight and squeezed with a mangle under 2.5 kg / cm ² . Then, it was heat-treated at 150 ° C. for 1 minute to obtain a base fabric for an airbag. In addition, as a comparative example, a base fabric for an airbag was similarly prepared for a woven fabric that was not impregnated with the above synthetic resin [Comparative Example 7].

The characteristics of the air bag base fabric thus obtained are shown in Table 1. The airbag base fabric of the present invention does not fray at the time of cutting processing, and does not have filament yarn loosening, and has low air permeability as an airbag, and also has a burst pressure,
The expansion and development time was good. On the other hand, the airbag base fabric of Comparative Example 7 suffered from fraying during the cutting process, and the yarns were scattered, resulting in a poor workability.

[0029]

[Table 1]

[0030]

EFFECTS OF THE INVENTION According to the present invention, while maintaining the mechanical strength required as an airbag, there are no problems such as fraying at the time of cutting and yarn loosening, which have been problems in the past.
It is possible to provide an airbag with good productivity, flexibility, light weight, and excellent storability, and it is possible to provide an inexpensive airbag compared to a conventional coated airbag. The occupant protection system can be promoted.

Claims (8)

[Claims] 1. In an airbag made of synthetic fiber cloth, the cloth is selected from synthetic resins made of polyamide type, polyester type, polyurethane type, resorcin formalin type, acrylic type, styrene butadiene type and nitrile butadiene type. A method for producing a base fabric for an air bag, comprising impregnating with a resin diluent containing at least one kind of synthetic resin. 2. The method for producing a base fabric for an air bag according to claim 1, wherein the polyamide resin is a water-soluble nylon resin. 3. The glass transition point (Tg) of the synthetic resin is −
The method for producing a base fabric for an airbag according to claim 1, which is 10 ° C. or lower. 4. The resin diluent has a solid content of 0.05 to 5.
The method for producing a base fabric for an air bag according to claim 1, which contains a resin in an amount of 00% by weight. 5. The method for producing a base fabric for an airbag according to claim 1, wherein the resin diluent is an aqueous emulsion. 6. The method for producing an airbag base fabric according to claim 1, wherein the resin diluent contains a flame retardant compound. 7. The method for producing an airbag base fabric according to claim 6, wherein the flame-retardant compound is at least one compound selected from halogen compounds, phosphorus compounds, and sulfur-containing nitrogen compounds. 8. The synthetic fiber cloth has a cover factor of 1.
The method for producing a base fabric for an airbag according to claim 1, which is a woven fabric in the range of 500 to 2,500.