JPH03287832A - Air bag - Google Patents

Abstract

PURPOSE:To obtain a lightweight air bag of a fabric, having flame contact resistance and moderate air permeability and folding properties by combining specific thermoplastic synthetic fiber and heat-resistant fiber at a prescribed ratio, providing yarn, weaving the resultant yarn at a high density and then sewing the woven fabric into a baglike form. CONSTITUTION:The objective air bag obtained by combining (A) thermoplastic synthetic fiber having <=5 denier single fiber size and <=1300kg/mm<2> Young's modulus with (B) heat-resistant fiber having <=2 denier single fiber size and >=300 deg.C thermal decomposition temperature at (90/10)-(30/70) ratio, providing yarn, then weaving the resultant yarn as warp and weft yarns at a high density and sewing the woven fabric into a baglike form. Furthermore, the aforementioned heat-resistant fiber is preferably high-tenacity heat-resistant fiber having >=16g/denier strength.

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The present invention relates to an air bag. Specifically, W
A.

<Prior art> Conventional airbags are made of thermoplastic synthetic fibers such as nylon 6, nylon 66, and polyester, and have a total fineness of 400.
~1000 denier strong kaffa filament is woven into a plain weave or ripstop fabric, coated with an elastomer such as chloroprene or silicone, and sewn into a bag as shown in Figure 4. , it has also been put into practical use as a device as shown in Figure 7 (Japanese Patent Publication No. 1983-30293, Utility Model Application No. 1983-1983).
81543, Utility Model Publication No. 17936, etc.)
. In other words, all of these airbag fabrics are heat resistant,
It has flame resistance, and when an aircraft or car crashes, the inflator will be removed as shown in Figure 7.
The inflator is designed to withstand the high-temperature blast and flame emitted from the combustion gas injection holes when current flows through the power cord ■, causing the inflator to burn and the air bag to expand into a spherical shape. There is. In other words, in order to pass the safety standards for airbags, elastomers are coated at a very long time, making the airbags heavy and stiff, which significantly reduces the ease of handling during sewing, and makes them difficult to fold. This increases the volume of the product, which poses an obstacle when installing it in a vehicle. In other words, due to its nature, an airbag device with a built-in airbag must be placed in front of the driver, and on the other hand, there is not enough space in the front as there is a steering wheel, various instruments, and windows, so it must be made as compact as possible. A new airbag device is desired. In addition, when attached to a steering wheel, etc., an airbag that is as light as possible is desired for ease of operation.

<Object of the Invention> The present invention has been made in order to solve such problems in the prior art. In other words, an air bag whose bag body is made of fabric that is not coated with elastomer such as chloroprene or silicone, and which can withstand the high-temperature blast and flame emitted from the inflator in the event of a collision. intended to provide.

<Structure of the Invention> That is, the present invention provides the following features:
The following thermoplastic synthetic fibers and heat-resistant fibers with a single yarn fineness of 2 de or less and a thermal decomposition temperature of 300°C or more in a ratio of 90:10 to 30:
: An air fabric characterized by being made by mixing fibers at a ratio of 70% to form a thread, using the threads as the warp and weft to weave at ^a5 degrees, and sewing the obtained fabric into a bag shape. bag.

(2) The airbag according to claim 1, wherein the heat-resistant fiber is a high-strength heat-resistant fiber having a strength of 16 SF/de or more.

3) The airbag according to claim 1 or 2, wherein the heat-resistant fiber is a para-aromatic polyamide fiber.

(4) The airbag according to any one of claims (1) to (3), wherein the fabric has a cover factor of 2000 or more.

(5) Claims (1) to 1, wherein the woven fabric has flame contact resistance of 5 seconds or more.
The airbag according to any one of (4).

(6) The airbag according to any one of claims (1) to (5), wherein the yarn is a tension-cut spun yarn produced by a tension-cutting method.

(Strength: A thermoplastic synthetic fiber with a single yarn m degree of 5 de or less, a Young's modulus of 1300 stories/- or less, and a single yarn fineness of 2 de or less,
90:10 to heat-resistant fiber with a thermal decomposition temperature of 300℃ or higher
A claim that the yarn is obtained by aligning and stacking the fibers at a ratio of 30:70, tearing them using a shooter between a supply roller and a tension cutting roller while preventing the fibers from being disordered, and then conjugating them with an air nozzle. The airbag according to any one of items (1) to (6).

Here, the thermoplastic synthetic fiber yarn is a fiber yarn made of a normal thermoplastic synthetic resin, and is made of nylon fiber, acrylic fiber, polypropylene fiber, or the like. Heat-resistant fibers are fibers with a thermal decomposition temperature of 300°C or higher, such as meta- or para-based wholly aromatic polyamides, specifically polymetaphenylene isophthalamide, polyparaphenylene terephthalamide, A copolymer of aramid and meta-aramid, for example 3
．． It is a para-aramid copolymerized with 4'-diaminodiphenyl ether, and also includes polyparaphenylene sulfone and polyparaphenylene sulfide.

It is a fiber made of polyetheretherketone, etc.

The present inventors have proposed that by blending such heat-resistant materials with ordinary thermoplastic synthetic fibers in the order of 1111, the high temperature emitted from the inflator can be improved without covering the fabric with an elastomer or the like. It was discovered that it is possible to obtain a fabric that does not melt, break, or burst into flames when exposed to blast waves or flames.

Further, the single fiber fineness of the thermoplastic synthetic IIH needs to be 5 de or less (preferably 2.5 de or less).

In other words, when the temperature exceeds 5 de, the resulting air bag becomes extremely rough and hard, although it is extremely important that the air bag be flexible because it needs to be folded into a small size.
It is no different from one coated with elastomer. In addition, the number of threads that make up the yarn is reduced,
Uniform blending with heat-resistant fibers makes it difficult to peel. Further, problems such as excessive air permeability of the fabric occur, which is not preferable. In addition, the Young's modulus of thermoplastic synthetic fiber is 1
3000/- or less.

When it exceeds 1300/-, many of the heat-resistant fibers that are other components have a high Young's modulus, so the Young's modulus of the yarn after mixing becomes high, and the fabric after weaving becomes coarse and hard. This is not desirable.

For the same reason, the single yarn fineness of the heat-resistant fiber needs to be 2 de or less. The Young's modulus of heat-resistant fibers is often higher than that of general synthetic fibers, and if it exceeds 2 de, the texture of the fabric will become rough and hard, which is not preferred.

On the other hand, when the blending ratio of the heat-resistant fibers is constant, the thinner the single fibers de and the larger the number of 11 fibers, the better the contact flame resistance, and from this point of view as well, the single fiber fineness of the heat-resistant fibers is preferably 2 de or less.

Moreover, the strength of heat resistance IIH is preferably 16 g/de or more. Below 169/de, the thermoplastic synthetic m width is 90:1.
When mixed fibers are used in a ratio of 0 to 30:70, it is difficult to obtain sufficient strength. Thermoplastic synthetic fiber (A> and heat resistant +!
The appropriate mixing ratio with woven fiber B> is 90/10 to 30 for Al6.
/ 70 (preferably 70/30 to 40/60
) is within the range. As shown in Table 1, Al6 is 90/
If it exceeds 10, heat and flame resistance will decrease. In addition, sufficient strength cannot be obtained unless the thickness of the thread is considerably thickened, which results in an undesirably thick fabric. Al6 is 30/
If it is less than 70, the modulus of the heat-resistant fiber is high, so the texture of the woven fabric becomes rough and hard, lacks flexibility, and the feel deteriorates. Furthermore, thermal shrinkage of thermoplastic synthetic fibers is limited, making it difficult to obtain dense fabrics with low air permeability.

Furthermore, many heat-resistant fibers are generally expensive, and the cost increases as the blending ratio increases.

Next, an example of a method for manufacturing a uniform mixed yarn of thermoplastic synthetic fiber and heat-resistant I1g will be described with reference to the drawings.

FIG. 1 shows a mixed l1vR arrangement. A is thermoplastic synthetic fiber,
B is a heat-resistant fiber, 1 is a supply nip roller 2 is a shooter, 13 is a tension nip roller, 4 is a suction air nozzle,
5 is a combination nozzle using a swirling flow, 6 is a delivery roller, and 7 is a mixed yarn.

The plastic synthetic fiber yarn A and the heat-resistant fiber yarn B are aligned and overlapped in front of the supply nip roller 1, and after passing through the supply nip roller, they are simultaneously torn off by a tension nip roller in the shoe shoe 2, and are drafted. while mixing evenly.

Next, the short fibers are taken up from the tension cutting roller by the suction air nozzle 4, and then given conjugation properties by entanglement and fluff wrapping by the rotating conjugation nozzle 5, and then taken up by the delivery roller 6, so that the fluff of the short fibers becomes the fiber. The yarn 7 is randomly wrapped around the side surface of the bundle. Since the obtained yarn has fluff in its form, the friction of the fabric set *rz is greater than that of a continuous filament mixed yarn, and seam slips are less likely to occur. Furthermore, compared to conventional spun yarns, the fibers have a higher degree of arrangement, are stretched to the limit by tension cutting, and have longer fiber lengths, resulting in a yarn with high strength, making it extremely suitable for use in airbags.

The obtained blended yarn was used for the warp and weft, and was woven into a plain weave at a high tIA density with a cover factor of 2000 or more, and after being subjected to scouring, heat setting, relaxing, and calendaring, the fabric was woven as shown in Figure 4. An air bag ■ is sewn into a bag body like this. In the figure, ■ indicates an inflator insertion hole, and ■ indicates an inflator combustion gas exhaust hole.

<Effects of the Invention> The airbag of the present invention has the following effects compared to conventional products.

+1j II The product is flexible and has excellent foldability.

(2) The volume when folded is small.

(3) It is lightweight.

(4) It has heat resistance and strength to withstand high-temperature blast waves and flames.

(5) Easy to sew.

(6) Not easily damaged by metal pieces, glass pieces, etc.

(7) There is little change in the performance of the airbag fabric even after a long period of time.

<Examples> The present invention will be explained below using examples. Note that each evaluation item in the Examples was evaluated according to the following method.

Inflator combustion test: A fabric woven using A/B mixed yarn is sewn into an airbag, and this is attached to an airbag device.The inflator is burned, and the airbag is evaluated by whether or not it is damaged. did.

Flame contact test: Hold the fabric sample mounted on the frame horizontally, and apply approximately 780 mm from the bottom.
We applied a flame at ℃ and measured the time it took for it to burn and form a hole.

Breathability; Measured by JIS L-1096 Frazier method.

Storing property: Fold the airbag along the dotted line ■ shown in Figure 5 (a) 10) to form the shape shown in 9, and add 5 phantom weights ■ as shown in Figure 6 to make it thicker. The temperature was measured.

Texture: The feel and flexibility of the fabric surface was sensory evaluated based on the assumption that the face would be strongly hit by an airbag in the event of a collision.

Example 1 Using the apparatus shown in Fig. 1, single yarn fineness 2 denier 1 strength 8
, 59/d, polyester fiber A with a total fineness of 4000 denier, a single yarn fineness of 0.75 denier, and a strength of 28 g/de.
, All @ [3000 denier para-aromatic polyamide fiber It (Technora Teijin product) are stacked and aligned, and the distance between the rollers is 100α, supply nip roller 1, shooter 2, and tension cutting roller 3. The fibers are simultaneously shredded at a speed of 200 m/lin at a speed of 16 times, and both fibers are uniformly mixed to form a thin short fiber bundle. In addition, the tension nip roller 3 and the delivery roller 6
The fiber bundle was passed through the fiber bundle at a speed ratio of 100:97 to provide entanglement, and the short liM fluff was randomly wrapped around the side surface of the fiber bundle.
Yarn 7 of 0 denier was obtained.

The ratio of polyester fibers and para-aromatic polyamide fibers in the obtained yarn was 57:43, and the average fiber length was 42α for polyester fibers and 3 for para-aromatic polyamide fibers.
It was 71. In addition, the strength and elongation of each yarn is 8.2.
g/de, 4.5% (both measured after 300T/M twisting), and fresh water shrinkage rate was 3.7%. Next, the main yarn was twisted at 300T/M to give a warp of 54 threads/inch and a weft of 50 threads/inch (cover factor 2206>
It is woven into a plain weave with a weave density of , and heat set.

After scouring and calendering, it was sewn into an air bag body as shown in FIG. Table 1 shows the evaluation results of the obtained bags.

Example 2 Using the apparatus of Example 1, polyester ultrafine fiber A with a single yarn fineness of 0.5 denier and a total fineness of 960 denier and a single yarn fiber rxO, 57' niel, strength 27 g/de, and a total fineness of 4000 denier were prepared. Para aromatic polyamide fiber (
Technora■) B are superimposed and aligned, and the distance between the rollers is 75cII between the supply nip roller 1, shooter 2, and tension nip roller 3.
The fibers are shredded simultaneously at a speed of 00 m/min, and both fibers are uniformly mixed to form a thin short fiber bundle, and then a tension-cutting nip roller is applied to an air nozzle 4 that has suction properties and a combination nozzle 5 that has swirling properties. 3 and delivery roller 6
The fibers were passed through the fibers at a speed ratio of 100:97, and the fluff of short fibers was randomly wrapped around the sides of the 1111 bundle to obtain Yarn 7 of 265 denier. The ratio of polynisal fibers and para-aromatic polyamide Il fibers in the obtained yarn was 32:68, and the average fiber length was polyester mH.
was 33 cm, and the para-aromatic polyamide fiber was 28 pieces. In addition, the strength and elongation of each yarn is 11.4g/
The shrinkage rate was 9%. Next, the main yarn was twisted at 420T/M to create a warp of 69 threads/1 nch.
li! 63 lines/1nch (cover factor 21
Plain weave with a weave density of 49> and heat set.

After being subjected to scouring, calendering, etc., it was sewn into an air bag body as shown in FIG. Table 1 shows the performance of the obtained bag.

Example 3 Using the @ position shown in Fig. 2, a single yarn fineness of 2.1 denier,
Polyester IaliA with a strength of 8.59/d and a total fineness of 300 denier, and a single yarn fineness of 1 denier and a strength of 289/d.
para-aromatic polyamide fiber IB with a total fineness of 100 deniers are adjusted so that the tension is the same, are aligned, are run in contact with a water adhesion roller 1 to impart moisture, and are then transferred to a supply roller 2 and delivered. Polyester III and para-aromatic polyamide fibers were uniformly mixed in the order of single fibers between a roller 4 and a mixed fiber air nozzle 3 to obtain a yarn 5 of 400 denier. The obtained yarn polyester mil fiber and para-aromatic polyamide il
The ratio with M is 75: 25T-1 strength is 8.39/
de (350T/M1! Measurement after yarn), fresh water shrinkage is 5
%Met.

Next, the main yarn was twisted at 250T/M to create a light 5
Plain weave with a weave density of 8 threads/1 nch, 54 threads/1 nch across (cover factor 2240), heat set, M kneading.

After calendering, etc., the material was sewn to form an airbag body as shown in FIG. Table 1 shows the performance of the obtained bag.

Example 4 An average fiber length of 10010 was produced by using the tow spinning apparatus shown in Fig. 3 to cut a polystyl fiber bundle with a single yarn fineness of 1.5 denier and a total fineness of 90,000 denier at a total draft of 7 times.
Os, average fiber length 89 m5+ obtained by cutting a sliver with a total denier of 13,000 denier and 111 bundles of para-aromatic polyamide with a single yarn fineness of 1.5 denier and a total fineness of 90,000 denier at a total draft of 7 times. , a sliver with a total denier of 13,000 and a modulus of 7100 υ/- are combined and passed through a gill process, and then through each process of roving and spinning to produce a sliver with a ratio of polyester fiber and para-aromatic polyamide fiber of 50:50. A spun yarn having a count of 10.6 (500 denier) was obtained.

Next, using this spun yarn, the warp density was 48 pieces/nch,
Weft density 46/1nCh (cover factor 2102
), was woven into a plain weave fabric with a basis weight of 228 g/butt, subjected to heat setting, scouring, calendering, etc., and then sewn to form an airbag body as shown in FIG. Table 1 shows the performance of the obtained bag.

Comparative Example 1 Nylon 6.6 fibers with a single yarn fineness of 6.0 denier and a total fineness of 840 denier were used for the warp and weft, and the warp and weft were 25.4 yarns/weft.
A woven fabric with a thickness of 0.3801 t/I was obtained by plain weaving with 1 nCh.

This fabric is coated with chloroprene rubber from Germany AUM△ R01.
1er-1-1ead, Continuous vu
One side of the fabric was calendered using lcanizing+achine to obtain a base fabric for an air bag having a thickness of 0.430 m/m.

(Vulcanization conditions = 180°C, 1.5 minutes). The obtained base fabric was sewn into an airbag as shown in FIG. 4, and its performance was evaluated.

The evaluation results are shown in Table 1.

Comparative Example 2 A polyester filament with a single yarn of 11 degrees and 2.5 denier, a strength of 8.5 g/d, and a total fineness of 500 denier.
It is woven into a plain weave with a weave density of 7/M twist and a light density of 50 threads/inch and weft 49 threads/inch (cover factor 2214), and after being subjected to scouring, calendering, etc., it is sewn and is shown in Figure 4. It was designed as an air bag body. Table 1 shows the performance of the obtained bag.

Examples 5-9. Comparative Examples 3 to 6 Single yarn fineness of thermoplastic synthetic fiber A and heat resistance 11 fB,
The same procedure as in Example 1 was carried out except that the mixing ratio of A and B was changed as shown in Table 2. The results are shown in Table 2.

[Brief explanation of the drawing]

Figure 1 is a side view of the tension-cut direct spinning device, △. B is a fiber yarn, 1 is a supply nip roller, 2 is a shooter 13 is a tension nip roller, 4 is a suction air nozzle,
5 is a swirling combination nozzle, 6 is a delivery roller, and 7 is a mixed yarn. Figure 2 is a side view of the filament mixing device. B is a l1ft yarn, 1 is a water adhesion roller, 2.4 is a nip roller, 3 is a mixed fiber air nozzle, and 5 is a mixed fiber yarn. Figure 3 is a side view of the tow spinning device, 1 is the supply tow, 3.4
, 5.6, 7.8.9, the nip roller 2 is a set heater, 10 is a crimper, 111 is a sliver, and 12 is a storage can. Figure 4 is a schematic diagram of the airbag ■, (a) is a front view,
(01 is a cross-sectional view, ■ is an inflator insertion hole, and ■ is an inflator j21 combustion gas exhaust hole. (C) is a schematic diagram explaining how to fold the airbag, showing folding along the dotted line ■. (C) shows the folded airbag. Figure 6 shows the thickness of the folded airbag between This is a schematic diagram explaining how to measure the
■ indicates the load weight, and t indicates the thickness of the folded airbag. Figure 7 is a schematic diagram of the airbag 61i1, where ■ is the folded airbag, ■ is the inflator, ■ is the combustion gas injection hole, ■ is the power cord, ■ is the case, and ■ is the airbag between the case and the inflator. The tightening to give it a stage name is a tool. @ is the shape when the air bag ■ is inflated.

Claims (7)

[Claims] (1) Single yarn fineness 5 de or less, Young's modulus 1300 kg/m
90:10 of thermoplastic synthetic fiber of m^2 or less and heat-resistant fiber with a single yarn fineness of 2de or less and a thermal decomposition temperature of 300°C or more.
It is characterized in that it is made by mixing fibers at a ratio of ~30:70 to form threads, weaving the threads at high density using the threads as warp and weft, and sewing the obtained fabric into a bag shape. air bag. (2) The airbag according to claim 1, wherein the heat-resistant fiber is a high-strength heat-resistant fiber having a strength of 16 g/de or more. (3) The airbag according to claim (1) or (2), wherein the heat-resistant fiber is a para-aromatic polyamide fiber. (4) The airbag according to any one of claims (1) to (3), wherein the fabric has a cover factor of 2000 or more. (5) Claims (1) to 1, wherein the woven fabric has flame contact resistance of 5 seconds or more.
The airbag according to any one of (4). (6) A claim in which the yarn is a tension-cut spun yarn produced by a tension-cutting method (
The airbag according to any one of 1) to (5). (7) The yarn has a single yarn fineness of 5 de or less and a Young's modulus of 1300 k.
g/mm^2 or less thermoplastic synthetic fiber and single yarn fineness 2d
e or less, heat-resistant fibers with a thermal decomposition temperature of 300°C or more
:10 to 30:70 ratio, the fibers are aligned and stacked, and the fibers are torn off using a shooter between the supply roller and the tension cutting roller while preventing the fibers from being disordered, and then the yarn is conjugated with an air nozzle. Claims (1) to (6)
Airbags listed in any of the above.