JP2003213573A - Base fabric for air bag and air bag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an air bag base fabric simultaneously having good heat resistance, flame retardancy and storability by the low coating of a reactive resin-containing silicone resin, and to provide an air bag. <P>SOLUTION: This air bag base fabric is characterized by comprising a synthetic fiber woven fabric and adhering a reactive resin-containing silicone resin to at least one side of the synthetic fiber woven fabric in a range of 5 to 20 g/m<SP>2</SP>. The air bag is characterized by using the air bag base fabric. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to heat resistance, flame retardance,
The present invention relates to a base fabric for an airbag that also has a storability and an airbag made of the same.

[0002]

2. Description of the Related Art In recent years, various types of airbags have been developed in order to ensure the safety of passengers in the event of accidents in various transportation means, especially in automobiles, and their effectiveness has been recognized and rapidly put into practical use. It is progressing. The environment in which the airbag is used is not limited, and an airbag having stable mechanical performance is required even in a severe environment such as high temperature or low temperature.

Conventionally, a plain woven fabric using nylon 6.6 or nylon 6 filament yarn of 334 to 1112 decitex is used for an air bag, and chloroprene and chlorosulfone are used to improve heat resistance, flame retardancy and air barrier property. It was made by applying an elastomer resin such as synthetic olefin or silicone and other synthetic rubber, cutting the laminated base fabric, and sewing it into a bag.

When a chloroprene elastomer resin is applied to a filament woven fabric to form a base fabric, it is necessary to apply 90 to 120 g / m ² to the woven fabric from the viewpoint of heat resistance and flame retardancy. However, there is a problem that the package volume becomes large in terms of storability. Compared to chloroprene elastomer resin, in the case of silicone elastomer resin, which is more excellent in heat resistance and cold resistance, the coating amount is 40 to 60 g / m ² and the weight is light, but the storability and compactness have improved considerably, but it is still insufficient. In addition, there is a problem that it is difficult to fold the bag when storing it by folding it into a package. Further, the process of applying and laminating the elastomer is complicated, and there is a problem in terms of productivity.

Therefore, in recent years, in order to solve such problems, an air bag using a non-coated base cloth made by high-density weaving has been attracting attention. As a corresponding technology, a high-density non-coated airbag composed of a polyamide fiber woven fabric such as nylon 6.6 or nylon 6 or a polyester fiber woven fabric is being studied. On the other hand, 20
With the revision of US regulation FMVSS208 in 2000, dualization of the inflator is being considered. Since this inflator will be a two-stage deployment system, the gas output of the second stage will be larger than the output of the conventional inflator. The improvement of heat resistance is required by increasing the output of the inflator. Due to this problem, the heat resistance of uncoated products is not sufficient. Further, the silicone-coated product also requires a thick coating of 40 to 60 g / m ² from the viewpoint of heat resistance and flame retardancy, and it cannot be said that the storability is sufficient.

[0006]

SUMMARY OF THE INVENTION In view of the drawbacks of the conventional air bag, the present invention provides a base fabric for an air bag and an air bag which have heat resistance, storability and flame retardancy at the same time. Is.

[0007]

The present invention adopts the following means in order to solve the above problems. That is, the airbag base fabric of the present invention is characterized by being made of a synthetic fiber woven fabric and having a reactive resin-containing silicone resin adhered to at least one surface within a range of 5 to ²⁰ g / m ^2. It is a thing. The reactive resin is preferably contained in the range of 5 to 60 parts by weight with respect to 100 parts by weight of the silicone resin. It is also preferable that the reactive resin is a melamine resin.

The airbag of the present invention is characterized by having such an airbag base fabric.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION Synthetic fiber woven fabrics according to the present invention include nylon 6.6, nylon 6, nylon 12, nylon 4.6 and copolymers of nylon 6 and nylon 6.6, nylon 6 with polyalkylene glycol, Polyamide fiber copolymerized with dicarboxylic acid or amine, homopolyester such as polyethylene terephthalate and polybutylene terephthalate, and aliphatic dicarboxylic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid or adipic acid as an acid component constituting the repeating unit of polyester. Polyester fiber copolymerized with acid, aramid fiber typified by copolymerization with paraphenylene terephthalamide and aromatic ether, rayon fiber, polysulfone fiber, ultra high molecular weight polyethylene fiber and sea mainly composed of the above synthetic fiber. Synthetic fiber fabrics are used consisting of a polymer array fiber having a structure. Among these, polyamide fiber and polyethylene terephthalate fiber are preferable, and nylon 6.6 and nylon 6 are more preferable from the viewpoint of impact resistance. Such fibers may contain various additives that are usually used for improving the productivity or the characteristics in the manufacturing process and the processing process of the raw yarn. For example, a heat stabilizer, an antioxidant, a light stabilizer, a smoothing agent, an antistatic agent, a plasticizer, a thickener, a pigment, a flame retardant and the like can be contained.

In the base fabric for an air bag of the present invention, a reactive resin-containing silicone resin is attached to the synthetic fiber woven fabric. The silicone resin forms a carbonized film when burned. This carbonized film shuts off the air and eventually extinguishes the fire. In the present invention, however, it is important that the reactive resin is contained for extinguishing the fire. A silicone resin alone does not easily extinguish a carbonized film when the adhesion amount is reduced, but it is difficult to extinguish a fire, but the inclusion of a reactive resin has an effect of easily crosslinking the resin to form a carbonized film.

The reactive resin is preferably a melamine resin or an epoxy resin. Furthermore, a melamine resin is more preferable from the viewpoint of high reactivity. The higher the reactivity, the easier it is to form a carbonized film and the easier the fire is to extinguish.

The amount of the reactive resin added is preferably in the range of 5 to 60 parts by weight with respect to 100 parts by weight of the silicone resin. If the amount is less than 5 parts by weight, the film strength cannot be increased and thus the flame retardancy cannot be improved. Further, if the content exceeds 60 parts by weight, the silicone resin becomes hard and the texture is deteriorated, so that the storability is deteriorated. Further, from the viewpoint of storability, it is preferable to add the reactive resin in an amount of 5 to 40 parts by weight.

The amount of the reactive resin-containing silicone resin attached should be within the range of 5 to ²⁰ g / m ² . If the adhesion amount is less than 5 g / m ^2, it is difficult to form a carbonized film and the flame retardancy deteriorates. On the other hand, if it exceeds 20 g / m ² , the thickness increases and the storability deteriorates.

A catalyst is preferably added to the melamine resin in order to accelerate the reaction and promote crosslinking. Regarding the catalyst, it is preferable to add an organic amine salt-based catalyst, an inorganic salt-based catalyst, or an inorganic metal salt-based catalyst. As the melamine-based resin, trimethoxymethylol-type and hexamethoxymethylol-type melamine-based resins are preferable because of high reactivity. Among them, hexamethoxymethylol-type melamine-based resin having many crosslinking points is particularly preferable because it increases the film strength by crosslinking. If the reactivity is lower than that of these resins, it becomes difficult to form a carbonized film of the silicone resin, and thus it becomes difficult to improve the flame retardancy.

As the silicone resin to be used, dimethyl type silicone, methyl vinyl type silicone, methylphenyl type silicone and fluoro type silicone are used.

The basis weight of the airbag base fabric of the present invention is preferably 300 g / m ² or less in terms of weight reduction, and the bending resistance is 100 mm or less in both the warp and weft directions. It is preferable from the viewpoint of flexibility. In addition, the tensile strength of the airbag base fabric is 300 N /
cm or more, breaking elongation of 15% or more, and tear strength of 50 N or more are preferable from the viewpoint of storability of the airbag and prevention of rupture when used as an airbag.

An example of a method of manufacturing an airbag that satisfies the above requirements is shown below. First, the diameter of the airbag base cloth is 7
Two 25 mm circular fabrics are cut by a punching method, and three circular reinforcing fabrics having a diameter of 200 mm made of the same fabric are laminated in the center of one circular fabric to form 110 mm and 145 mm diameters.
mm and 175 mm lines were sewn by a lock stitch using a sewing thread having a total fineness of nylon 6.6 fibers of 1,390 decitex for both upper and lower threads, and a hole having a diameter of 90 mm was provided to serve as an inflator attachment port. Further, one circular reinforcing cloth made of the same base cloth having a diameter of 75 mm is laid against the position of 255 mm in the bias direction from the center portion, and the diameter is 50 mm, 60.
On the mm line, the upper and lower threads are sewn by sewing with nylon 6.6 fibers having a total fineness of 1,390 decitex by lock stitch, and two vent holes with a diameter of 40 mm are provided. Next, the reinforcing fabric side of the circular fabric is placed outside,
Sewing machine by double chain stitching on the other circular fabric with the warp axis offset by 45 degrees and with a total diameter of nylon 6.6 fibers of 1,390 decitex for both upper and lower threads on the circumference of 700 mm and 710 mm in diameter. After sewing, turn the bag inside out 6
A 0 L capacity airbag is made.

As the coating method, knife coating, comma coating, gravure coating and the like can be used, but knife coating is preferable because it reduces the amount of adhesion.

The woven fabric may be a yarn having a flat single yarn cross section. When a yarn having a flat cross section with a ratio of the major axis to the minor axis of the cross section, that is, an aspect ratio of 1.5 to 6.0 is used, the thickness of the base cloth can be reduced and the storability is improved. Flat cross-section yarns are usually oval but have an aspect ratio of 1.5
Any shape other than an elliptical shape may be used as long as it satisfies ~ 6.0. For example, it may be a left-right symmetrical type such as a rectangle, a rhombus, or a cocoon type, or may be a left-right asymmetric type, or a combination thereof, and further, with the above as the basic type, there are protrusions, depressions, or partially hollow portions. May be.

The airbag having the airbag base fabric of the present invention can be used for a driver airbag, a passenger airbag, a rear seat airbag, a side airbag, an inflatable curtain airbag, and the like. You can

[0021]

EXAMPLES The present invention will be described in more detail with reference to examples. Various evaluations in the examples were carried out according to the following methods.

Tear strength: JIS L1096 (8.1
5.1A method).

Tensile strength: JIS L1096 (8.1)
2.1A method).

Flame retardance: Measured by FMVSS-302. Burning speed of 100 mm / min or less was marked with ◯, and burning speed exceeding 100 mm / min was marked with x.

Storability test: As shown in FIG. 1, an air bag having a capacity of 60 L was first folded into four bellows from the left and right so as to have a size of 150 × 150 mm, and then folded into four bellows from above and below, and then folded. As shown in FIG. 2, the bag was subjected to a load of 10 N, and the thickness (mm) of the bag after 2 minutes was measured. Examples 1 to 10 and Comparative Examples 1 to 8 Nylon 6.6 filament filament yarn having total fineness and number of filaments shown in Table 1, strength of 8.4 cN / decitex and elongation of 23.0% Was used in a water jet room to obtain a plain woven fabric having the woven densities of the warp yarn and the weft yarn shown in Table 1. This fabric is then treated with 0.5 g / l of sodium alkylbenzene sulfonate and 0.5 g of soda ash.
After soaking in a 80 ° C hot water bath containing g / l for 3 minutes, 1
It was dried at 30 ° C. for 3 minutes and then heat heat set at 180 ° C. for 1 minute. This fabric was coated with a silicone resin and a melamine resin in a formulation as shown in Table 1 with a knife coater and then dried at 190 ° C. for 2 minutes to obtain a base fabric for an airbag.

Thereafter, using this airbag base cloth,
An airbag having a capacity of 60 L was produced. Example 11 A filament yarn having a flat cross section of nylon 6.6 fiber having a total fineness of 470 decitex, 96 filaments, a strength of 8.4 cN / decitex and an elongation of 22.5% is used in a vertical jet in a water jet room. A plain weave having a weft density of 46 yarns / 2.54 cm was obtained. Then
This woven fabric was scoured, dried, and heat-set in the same manner as in Example 1, and then coated with a silicone coater and a melamine resin in a formulation as shown in Table 1 using a knife coater, and then 1
It was dried at 90 ° C. for 2 minutes to obtain a base fabric for airbag. Then, using this air bag base fabric, as in Example 1, 6
An air bag of 0 L capacity was produced. Example 12 Using a filament yarn having a flat cross section of nylon 6.6 fiber having a total fineness of 350 decitex, 96 filaments, a strength of 8.4 cN / decitex, and an elongation of 22.5%, a vertical yarn in a water jet room A plain weave having a weft density of 53 yarns / 2.54 cm was obtained. Then
This woven fabric was scoured, dried, and heat-set in the same manner as in Example 1, and then coated with a silicone coater and a melamine resin in a formulation as shown in Table 1 using a knife coater, and then 1
It was dried at 90 ° C. for 2 minutes to obtain a base fabric for airbag. Then, using this air bag base fabric, as in Example 1, 6
An air bag of 0 L capacity was produced. Comparative Example 9 A filament yarn having a flat cross section of nylon 6.6 fibers having a total fineness of 470 decitex, 96 filaments, a strength of 8.4 cN / decitex, and an elongation of 22.5% is used in a vertical jet in a water jet room. A plain weave having a weft density of 46 yarns / 2.54 cm was obtained. Then
This woven fabric was scoured, dried, and heat-set in the same manner as in Example 1, and then coated with a silicone coater and a melamine resin in a formulation as shown in Table 1 using a knife coater, and then 1
It was dried at 90 ° C. for 2 minutes to obtain a base fabric for airbag. Then, using this air bag base fabric, as in Example 1, 6
An air bag of 0 L capacity was produced. Comparative Example 10 A filament yarn having a flat cross section of nylon 6.6 fiber having a total fineness of 350 decitex, 96 filaments, a strength of 8.6 g / decitex, and an elongation of 22.5% is used in a warp yarn in a water jet room. A plain weave having a weft density of 53 yarns / 2.54 cm was obtained. Then
This woven fabric was scoured, dried, and heat-set in the same manner as in Example 1, and then coated with a silicone coater and a melamine resin in a formulation as shown in Table 1 using a knife coater, and then 1
It was dried at 90 ° C. for 2 minutes to obtain a base fabric for airbag. Then, using this air bag base fabric, as in Example 1, 6
An air bag of 0 L capacity was produced.

The silicone resin referred to in Examples and Comparative Examples is 100 parts by weight of DY38-075 (manufactured by Toray Dow Corning Silicone Co., Ltd.) as a silicone resin and SRX212 (manufactured by Toray Dow Corning Silicone Co., Ltd.) as a catalyst. ) Is added to 0.5 parts by weight of the flame retardant.

The melamine-based resin is obtained by adding 1 part by weight of an organic amine salt-based catalyst as a catalyst to a hexamethoxymethylol-type melamine-based resin.

The characteristics of the airbag base fabrics and airbags of Examples 1 to 12 and Comparative Examples 1 to 10 were evaluated and shown in Table 1.

As is clear from Table 1, Examples 1 to 12 were excellent in flame retardancy and storability. Comparative Examples 1, 2, 4
Nos. 10 to 10 were inferior in flame retardancy. Comparative Example 3 was inferior in storability.

[0031]

[Table 1]

[0032]

According to the present invention, since it is possible to provide a base fabric for an airbag and an airbag having heat resistance, flame retardancy, and storability at the same time, the occupant protection system using an airbag is promoted. be able to.

[Brief description of drawings]

FIG. 1 is a diagram illustrating a method of folding an airbag in a storability test.

FIG. 2 is a diagram illustrating a method for measuring a bag thickness when a load is applied to an airbag during a storability test.

[Explanation of symbols]

1: Plan view of 60L capacity airbag 2: Folding direction 3: Plan view of the airbag folded from the left and right 4: Plan view of the airbag folded from the top and bottom 5: Side view of the airbag folded from the top, bottom, left and right 6: load 7: Thickness of the airbag when a load is applied

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Claims (4)

[Claims] 1. A synthetic fiber woven fabric, and 5 to 20 g of a reactive resin-containing silicone resin on at least one surface thereof.
A base fabric for an air bag, characterized in that it adheres within a range of / m ² . 2. The airbag base fabric according to claim 1, wherein the reactive resin is contained in the range of 5 to 60 parts by weight with respect to 100 parts by weight of the silicone resin. 3. The airbag base fabric according to claim 1, wherein the reactive resin is a melamine resin. 4. An airbag having the airbag base cloth according to claim 1.