JP2002266161A - Raw yarn for airbag and fabric for airbag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flexible raw yarn for airbag, having high toughness and moderate interlacing strength, and to provide a fabric for airbag having low air permeability, high flexibility and excellent containability and also high shock-absorbing ability. SOLUTION: This raw yarn for airbag is made of polyamide multifilaments and meets simultaneously the following requirements: (1) 96% sulfuric acid relative viscosity is >=3.5, (2) single filament fineness is <=3.3 dtex, (3) total fineness is 200-700 dtex, (4) tenacity is <=6.5 cN/dtex, (5) elongation is >=27%, (6) boiling water shrinkage is <=6%, and (7) stress at 10% elongation is <=3.6 cN/dtex. The other objective fabric for airbag is made from the above raw yarn.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a yarn for an airbag and a fabric for an airbag. More specifically, the airbag raw yarn having flexibility, high toughness, and moderate confounding strength and the airbag raw yarn are used to provide low air permeability and excellent flexibility and storage properties. The present invention relates to an airbag fabric having excellent shock absorption resistance.

[0002]

2. Description of the Related Art An airbag that expands upon collision of a vehicle, for example, an automobile, absorbs the impact of a seated occupant, and functions to protect the airbag is used as a device for ensuring the safety of the occupant in the vehicle. It has become indispensable, and in recent years, its mounting rate on vehicles has been increasing. The demand for improved reliability of the airbag as a safety device has been further intensified, but other required performances of the airbag include the cost reduction, compactness of the airbag device, and Since there are various problems such as a demand for preventing occupant's facial abrasion, there is a demand for an even higher degree of quality improvement for the fabric for the airbag constituting the airbag, and further for the yarn for the airbag.

Further, in the conventional airbag, the airbag is momentarily inflated by the high-temperature and high-pressure gas generated by the inflator, so that the occupant's face comes into contact with the inflated airbag and the impact on the occupant is reduced. For this reason, it is compatible with a system that exhausts high-temperature and high-pressure gas in the airbag from the vent hole provided on the inflator mounting side of the airbag. Therefore, development of an airbag base fabric that can reduce the impact of an occupant without using a vent hole, that is, has excellent shock absorption resistance, is desired.

A number of techniques have been proposed to realize an airbag having excellent foldability and a small storage capacity without impairing the mechanical properties of the airbag. Japanese Patent Application Laid-Open No. 41438 discloses that the above-mentioned object can be achieved by using an airbag base fabric made of a yarn having a strength of 8.5 g / d or more and a single-denier of 3 denier or less. I have. That is, the technique described in Japanese Patent Application Laid-Open No. 1-4438 is a technique related to a so-called coating base fabric in which an elastomer such as chloroprene rubber is applied to the surface of a fabric, and the flexibility of the coating base fabric is improved. The effect is to obtain a base fabric for an airbag having excellent foldability. However, although the coated base fabric obtained in the art is satisfactory in its flexibility and foldability, it is not satisfactory in gas permeability and shock absorption for reducing impact to occupants.

[0005] Japanese Patent Application Laid-Open No. Hei 4-201650 discloses an airbag fabric which is lightweight, has excellent flexibility and storage properties, and has excellent mechanical properties.
An airbag fabric using a polyamide multifilament consisting of a plurality of single yarns having a modified cross section having a denier of 12 to 12 deniers and a deformation degree of 1.5 to 7.0 is disclosed.

However, the technology described in Japanese Patent Application Laid-Open No. Hei 4-201650 also provides a lightweight, flexible and highly packable airbag base when applied as a coating base fabric coated with an elastomer such as silicone rubber. It is claimed that a cloth can be obtained, and the effect as a non-coated base cloth is described in Examples of the Japanese Unexamined Patent Application, although the cloth before silicone rubber application is considered to be flexible and excellent in foldability. No mention is made of gas permeability, which is an important required characteristic of the non-coated base fabric, and the change with time of the gas permeability, and the shock absorption resistance for reducing the impact on the occupant. And, from the result of actually tracing the technology, it is possible to obtain the result that the non-coated base fabric has excellent foldability, and at the same time satisfies that the gas permeability is low and the gas permeability has little change with time. could not.

Further, US Pat. No. 6,037,047 discloses that it is effective to use a diamond-shaped or S-shaped flat cross-section yarn as a raw yarn of a polyester fiber cloth having excellent covering properties and flexibility. It is disclosed that the polyester fiber fabric is also useful as a fabric for an airbag.

[0008]

However, the diamond type and S type described in US Pat. No. 6,037,047 are not disclosed.
Polyester fiber cloth using a flat cross-section yarn having a letter shape is certainly excellent in covering properties and flexibility, but especially for flexibility required for airbag cloth, the conventional nylon 66 fiber is used. Did not have a remarkable effect as compared with the following fabric. In addition, the technique does not mention any effects such as low gas permeability and little change in gas permeability with time.

As described above, in the above-mentioned known art,
In each case, improvement in flexibility and / or air permeability is taken into consideration, but no consideration is given to improvement in shock absorption resistance for reducing the impact on occupants.

On the other hand, with respect to the improvement of the shock absorption resistance of the airbag, Japanese Patent Application Laid-Open No. 5-213131 discloses a technique for protecting the face using ultra-fine fibers produced by subjecting sea-island composite fibers to an alkali treatment. However, this technique cannot manufacture an industrially and commercially inexpensive airbag because of the high production cost of ultra-fine fibers.

[0011] The present invention has been achieved as a result of studying to solve the above-mentioned problems in the conventional technology. Accordingly, an object of the present invention is to provide an airbag yarn having flexibility, high toughness, and moderate confounding strength, and to use the airbag yarn, to provide low air permeability and excellent flexibility and storage. Another object of the present invention is to provide a fabric for an airbag having excellent shock absorbing properties.

[0012]

Means for Solving the Problems In order to solve the above-mentioned problems, a yarn for an airbag of the present invention is a yarn for an airbag containing polyamide multifilament as an essential component. It is characterized in that the conditions of (7) to (7) are simultaneously satisfied. (1) The relative viscosity of 96% sulfuric acid of the yarn is 3.5 or more. (2) The fineness of a single yarn is 3.3 dtex or less. (3) The total fineness of the yarn is 200 to 700 dtex. (4) The strength of the yarn is 6. 5 cN / dtex or more (5) Elongation of yarn is 27% or more (6) Boiling water shrinkage of yarn is 6% or less (7) Stress at 10% elongation of yarn is 3.6 cN / dtex
Less than.

The fabric for an airbag according to the present invention is characterized in that the above-described yarn for an airbag is used for both or one of the warp and the weft constituting the fabric.

In the airbag fabric of the present invention, the following (a) and (b) are preferred embodiments, respectively, and it is expected that a further excellent effect can be obtained by applying these conditions. Can be. (A) The tensile strength in both the warp and weft directions of the fabric is 5
00N / cm or more and tensile elongation is 28% or more. (B) The number of entanglements of the warp and / or weft is 5 / m or less, the total fineness of the warp is D1 (dtx), the weaving density is N1 (line / 2.54 cm), and the total fineness of the weft is D2 ( dt
x), when the weaving density is N2 (lines / 2.54 cm), (D1 × 0.9) ^1/2 × N1 + (D2 × 0.9) ^1/2
× N2 cover factor of 1500 to 230
0, woven with a permeability of 0.5cc / cm
² / sec or less.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION The yarn for an air bag and the fabric for an air bag of the present invention will be described below in detail. Examples of the polyamide which is a fiber material of the yarn for the airbag of the present invention include polyhexamethylene adipamide (nylon 66), polycapramide (nylon 6), polytetramethylene adipamide (nylon 46) and copolymers of these polymers. Polymers, blends, etc. are used. Even if applied to any of the above materials, a suitable effect can be obtained. Especially when applied to polyhexamethylene adipamide (nylon 66) fiber, it has excellent flexibility and can be stored. A fabric for an airbag having excellent properties is obtained.

The yarn for an airbag of the present invention is composed of the above-mentioned polyamide multifilament, and the sulfuric acid relative viscosity of the yarn is 3.5 or more, preferably 3.7 or more. When the relative viscosity of sulfuric acid is less than the above range, physical properties having a strength of 6.5 cN / dtex or more and an elongation of 27% or more cannot be obtained. The relative viscosity referred to herein is that 2.5 g of a sample is dissolved in 25 cc of 96% concentrated sulfuric acid,
It is a value measured and determined using an Ostwald meter at a constant temperature of 25 ° C. constant temperature bath.

The single yarn fineness of the yarn for an airbag of the present invention is 3.3 dtex or less, especially 2.5 dtex.
The following is preferred. If the single-fiber fineness exceeds the above range, when used as an airbag fabric, the fabric lacks flexibility and is inferior in storability, and the covering property is insufficient. In general, as long as the mechanical properties are satisfied, the smaller the single yarn fineness, the more favorable the tendency.

The total fineness of the airbag yarn of the present invention is 2
00 to 700 Dtex, preferably 280 to 55
0Dtex. If the total fineness is less than the above range, the mechanical properties of the airbag fabric are not sufficient, and if the total fineness exceeds the above range, the airbag becomes bulky and heavy, impairing the storability and weight reduction. This is not preferred because of the tendency.

The strength, which is a mechanical property of the yarn for an airbag of the present invention, is 6.5 cN / dtex or more, particularly preferably 7.0 cN / dtex or more, and the elongation is 27% or more. In particular, the elongation is 30% or more. When the strength is less than the above range, a satisfactory tear strength as an airbag fabric cannot be obtained, and when the elongation is less than the above range, a satisfactory impact absorption resistance upon inflation of the airbag is obtained. I can't get it.

The boiling water shrinkage of the airbag yarn of the present invention is preferably 6% or less, particularly preferably 5% or less. If the boiling water shrinkage ratio is larger than the above range, the dimensional stability is deteriorated, so that the processability in producing the fabric for the airbag is deteriorated, and the obtained base fabric has defects such as wrinkles and variations in air permeability. Tends to occur.

The stress at 10% elongation obtained from the stress-elongation curve of the yarn for an airbag of the present invention is 3.6 cN / dte.
x or less, and particularly preferably 3.3 cN / dtex or less. If the stress at 10% elongation exceeds the above range, the effect of improving the shock absorption resistance when an occupant comes into contact with the airbag during inflation when mounted as an airbag is not preferable.

That is, the yarn for an airbag of the present invention comprises:
Conditions for (1) sulfuric acid relative viscosity, (2) single yarn fineness, (3) total fineness, (4) strength, (5) elongation, (6) boiling water shrinkage, and (7) stress at 10% elongation At the same time, it is flexible, high in toughness, and has a suitable confounding strength, and with low air permeability and excellent flexibility, storage that could not be achieved with the conventional technology,
It is possible to provide an airbag fabric having excellent shock absorption resistance.

Further, the fabric for an airbag of the present invention comprises a novel yarn for an airbag having the above-mentioned characteristics, and a warp and / or
Or it is preferable to use it for a weft.

The fabric for an airbag of the present invention has a tensile strength in both the warp direction and the weft direction of the fabric of 500 N /.
cm or more, particularly preferably 600 N / cm, and more preferably the tensile elongation is 28% or more, particularly preferably 30% or more. If the tensile strength is less than the above range, the safety as an airbag fabric is impaired, and if the elongation at break is less than the above range, the present invention sufficiently satisfies the intended shock absorption resistance. It is not preferable because it becomes impossible.

In the fabric for an airbag of the present invention, the number of entanglements of the warp and / or weft constituting the fabric is preferably 5 / m or less, more preferably 2 / m or less. Preferably it is 0. The yarn for airbags is generally entangled to improve the processability during weaving, but this entanglement is substantially eliminated when the fabric is woven after weaving. It is preferable that the entanglement of the raw yarn has an appropriate entanglement strength. If the entanglement of the airbag fabric exceeds the above range, it is not preferable because the covering property is poor, the air permeability of the fabric is high, and the reliability of the deployment speed of the airbag is lost. In order to satisfy a certain standard value of air permeability, disadvantages such as a need for a design with a higher woven density are required.

Furthermore, the air of the present invention satisfying the above-mentioned characteristics
The bag fabric has a cover factor of 1500 to 230.
0, preferably 1900 to 2100.
Preferably, it is woven in such a way. Here, the cover
The factor is the total fineness of the warp as D1 (dtx), the weaving density
Is N1 (book / 2.54 cm), and the total fineness of the weft is D2 (d
tx), when the weaving density is N2 (lines / 2.54 cm)
And (D1 × 0.9) ^1/2× N1 + (D2 × 0.9)^1/2
× N2. Cover factor is above
Below the range, when used as an airbag, breathability
High reliability of the airbag deployment speed
Not only, especially when applied to non-coated airbags
Is likely to cause misalignment, which may cause a change with time in air permeability.
Is not preferred because On the other hand, the cover factor
If the value exceeds the above range, the weaving density will increase.
Not only deteriorates flexibility and storage, but also the amount of fiber used
And weaving costs increase,
No.

In addition, the airbag fabric of the present invention is preferably a non-coated fabric used without being coated with an elastomer or the like, and is specified in JIS L 1096 (6.27.1A method). Air permeability measured by the method is 0.5 ml / cm ² / se
c or less, particularly 0.3 ml / cm ²
/ Sec or less. The air permeability measured by the same method as described above after folding the base fabric is preferably 0.75 ml / cm ² / sec or less, and more preferably 0.5 ml / cm ² / sec or less.

If the air permeability before or after folding the fabric exceeds the above range, the reliability of the airbag may be lacking, for example, the deployment speed of the airbag may be reduced. The air permeability after folding is preferably within 150% of the air permeability before folding, and is preferably within 120%. If the air permeability after folding exceeds 150% of the air permeability before folding, it is not preferable because the air permeability of the folded bag becomes uneven when the folded bag is deployed, and the bag does not expand isotropically.

The air permeability after folding is generally better with a higher cover factor, smaller fineness of a single yarn, and better covering property within a multifilament. In particular, an airbag using the original yarn of the present invention is preferred. The fabric is very good.

The properties of the airbag fabric of the present invention are not particularly limited as long as they satisfy the mechanical properties required for an airbag, but preferably have a flexibility (rigidity) of 100 mm or less. Those satisfying the condition that the shock absorption resistance is 20 ° or less are preferable.

Next, an embodiment of the method for producing a yarn for an airbag of the present invention will be described with reference to the drawings. The raw yarn for an airbag of the present invention is produced by melt-spinning and drawing using a polyamide polymer, preferably a high-molecular-weight nylon 66 having a sulfuric acid relative viscosity of 3.5 or more.

First, the polymer is heated and melted by a spinning machine.
It is spun from the spinneret. In order to obtain the original yarn for an airbag of the present invention, the shape of the die hole is designed and used so that the yarn filament after spinning and cooling forms a desired cross section.

As shown in FIG. 1, the yarn (1) is cooled and solidified through a cooling section (2) and a spinning duct (3), and then an oil agent is applied by an oil supply device (4). Next, thread (1)
Are drawn at a predetermined speed by the pick-up rollers (5) and (6), and then heated and drawn by a roller group (7), (8) and (9).
Hot stretching. The drawn yarn (1) is
After being relaxed between the stretching roller (9) and the tension adjusting roller (10), the tension adjusting roller (10) and the winding machine (1) are relaxed.
3) After being entangled by the entanglement imparting device (11) installed therebetween, the entanglement is wound by the winder (13).

Here, the mechanical properties of the airbag yarn of the present invention can be obtained by appropriately selecting the stretching ratio and the relaxation treatment conditions in the above stretching step. A particularly preferred method is to perform stretching once under conditions that provide the same strength and elongation as conventional high-strength yarns for airbags, followed by a relaxation treatment at a relaxation rate of 5 to 12%, preferably 6 to 10%. is there. The relaxation process is usually performed in one stage, but may be performed in two or more stages using two pairs of relaxation rollers.

Next, yarn path regulating guides (12, 12 ') are arranged before and after the entanglement imparting device (11), and the yarn (1) passing through the yarn path regulating guide (12) is entangled with the entanglement imparting device (12). 11), and pressurized air is injected from the confounding nozzle to perform confounding processing. In addition, the entanglement imparting device (11) can be installed between the second stretching roller (9) and the tension adjusting roller (10). The yarn path regulating guides (12) and (12 ') are installed before and after the entangling apparatus (11) so that the yarn path of the yarn does not change. The injection pressure of the compressed air in the confounding device (11) is 0.2 to
It is 0.7 MPa, preferably 0.25 to 0.6 MPa. The tension at the time of confounding the yarn is set in the range of the fineness of the yarn (dtx) × 0.05 to 0.25 cN.

The total fineness of the airbag yarn is 200-70.
0dtex.
For example, an optimal total fineness is selected according to a driver's seat, a passenger's seat, a side airbag, an inflatable curtain, and the like, and a fabric for an airbag designed according to the total fineness can be obtained.

Next, the airbag yarn obtained by the above method is warped and woven. Further, the cloth obtained after weaving may be subjected to pressure treatment or calendering. In order to obtain the effect of the present invention as an airbag fabric, it is preferable to design the fabric so that the cover factor is 1500 to 2300. Weaving generally uses an efficient water jet loom,
A rapier room or an air jet room can be used. Thus, the airbag fabric of the present invention is obtained.

The yarn for an airbag of the present invention obtained in this manner is flexible, has high toughness, and has an appropriate confounding strength. It has low air permeability, excellent flexibility and storability that could not be achieved by technology, and also has excellent shock absorption resistance.

The yarn for an airbag of the present invention and the fabric for an airbag using the same are most suitable as a fabric for a non-coated airbag. It can also be used. Further, the present invention can be applied to uses other than airbags that require flexibility, low air permeability, and shock absorption resistance.

[0040]

The present invention will be described more specifically with reference to the following examples. The definitions of physical properties and measurement methods used in the text of the specification and the examples are as follows. (1) Fineness, strength and elongation: According to JIS L-1073, strength and elongation are test length 25 cm, tensile speed 30 cm /
It is a value measured in minutes.

(2) Stress at 10% elongation: JIS L-1
073 was calculated from the stress-elongation curve measured by the following equation. Stress at 10% elongation = (Strength at 10% elongation) /
(Fineness at 0% elongation).

(3) Number of confounds: For each yarn,
This is a value obtained by measuring the number of entangled portions having a length of 1 mm or more by the water immersion method for every ten pieces and converting the average value of the ten pieces into the number per 1 m. The immersion bath is 70cm long and 1 width
5 cm, depth 5 cm, 10 cm from both ends in the longitudinal direction
The one provided with a partition plate at cm was used. The bath was filled with pure water to a depth of about 3 cm, the raw yarn was immersed in the bath, and the pure water was replaced every measurement in order to eliminate the influence of impurities such as oils. The number of entanglements of the fabric was indicated by the average value of the number of entanglements present in the warp and the weft constituting the fabric.

(4) Tensile strength and tensile elongation of fabric: JIS
It measured according to L1096 (6.12.1A method).

(5) Air permeability: JIS L1096 (6.
27.1A method).

(6) Air permeability after folding: As shown in FIG.
First, the bellows were folded four times in the (II) direction from the left and right so as to be 0 × 150 mm.
II) is folded into bellows four times in the direction (II) from above and below, and the folded bags (III, IV) are
After adjusting for 48 hours under a load of 5 cN / cm ² in a temperature and humidity control room at 25 ° C. and 50% RH, the load was removed, the folding was released, and the same method as described above (JIS L1096) was used.
(6.27.1A method)).

(7) Flexibility: JIS L1096 (6.
19.1A method).

(8) Shock absorption: Airbag fabric is cut and sewn to prepare an airbag (A) having a radius of 34.5 cm, and a hole having a radius of 4 cm is formed as an inflator mounting port. Next, as shown in FIG. 3, an ultra-thin rubber balloon (B) is put in the airbag, air is put in, and the internal pressure is 0.2 kg.
/ Cm ^2, release a lead pendulum (C) made of 500 g suspended from a string (100 cm in length) from 45 °, hit the airbag (A), and return the pendulum by repulsion ( X °) was measured.

Example 1 Using an extruder-type spinning machine, 29 nylon 66 chips having a sulfuric acid relative viscosity of 3.8 were used.
It was melt spun at 5 ° C. That is, using a die having 192 holes, a yarn is spun from a spinning pack having this die, and the raw yarn 470 for an airbag is directly subjected to a spinning and drawing process.
The dtex yarn is produced, and the pre-stretching-two-stage stretching heat treatment-relaxation process shown in FIG. 1 is performed, that is, an oil supply roller, a take-up roller, a yarn supply roller, a first stretching roller, a second stretching roller, and a tension adjusting roller are formed. After successively passing, and subjected to stretching heat treatment and relaxation treatment, the film was wound by a winder.

At this time, the speed of the second stretching roller was set to 3500
m / min, the stretching ratio (second stretching roller speed / take-up roller speed) is 3.90 times, the relaxation rate is 6% (tension adjusting roller speed is 3290 m / min), and then the film is wound by a winder. Was. The temperature of each roller is room temperature (about 35 ° C.) for the take-up roller, 45 ° C. for the yarn feeding roller, 120 ° C. for the first stretching roller, 225 ° C. for the second stretching roller, and 1 ° for the relaxation roller.
40 ° C.

The entanglement device for imparting entanglement to the yarn was installed between the tension adjusting roller and the winding machine, and the entanglement yarn was wound by changing the high pressure air pressure using an entanglement imparting nozzle.

Next, the raw yarn for an airbag obtained by the above method is warped at a speed of 200 m / min, and then the weaving density is changed in a water jet loom to change the rotation speed to 8 m / min.
Weaved at 00 rpm. Thereafter, heat set processing was performed to obtain a fabric for an airbag.

Table 1 shows the production conditions of the thus obtained yarn and fabric, and the physical properties of the obtained yarn and fabric. The airbag fabric using the airbag yarn shown in Example 1 has excellent flexibility, air permeability, and shock absorption resistance as compared with the conventional airbag fabric using the yarn. I understand.

Comparative Example 1 A nylon 66 chip having a sulfuric acid relative viscosity of 3.8 was melt-spun at 295 ° C. using the same extruder type spinning machine as in Example 1. That is, using a die having 192 holes, yarn was spun from a spinning pack having the die, and a yarn of 470 dtex of the original yarn for airbag was produced by a direct spinning and drawing process. In this case, winding was performed with the second stretching roller speed set to 3500 m / min, the stretching ratio changed to 4.40 times, and the relaxation rate changed to 6%.
The temperature of each roller is as follows.
The yarn feed roller is 45 ° C, the first stretching roller is 120 ° C, the second
The stretching roller was at 235 ° C and the relaxing roller was at 140 ° C.

The entanglement device for imparting entanglement to the yarn was installed between the tension adjusting roller and the winding machine, and the entanglement yarn was wound by changing the high-pressure air pressure using an entanglement imparting nozzle.

Next, the yarn for an airbag obtained by the above method was warped at a speed of 200 m / min, and then woven at a rotation speed of 800 rpm in a water jet room while changing the weaving density. Thereafter, heat set processing was performed to obtain an airbag fabric.

Table 2 shows the production conditions of the thus obtained yarn and fabric, and the physical properties of the obtained yarn and fabric. The yarn for airbag shown in Comparative Example 1 is a yarn of the prior art, and has a low toughness and a large stress at 10% elongation of 4.0 cN / dtex, so that it has poor shock absorption resistance. You can see that.

[Examples 2 to 10 and Comparative Examples 2 to 5] In the same manner as in Example 1 and Comparative Example 1, raw yarns and fabrics for airbags were manufactured under the manufacturing conditions shown in Tables 1 and 2. . Tables 1 and 2 show the production conditions of each of the obtained yarns and fabrics and the physical properties of the obtained yarns and fabrics.
It was also described in.

[0058]

[Table 1]

[0059]

[Table 2] As is clear from the results shown in Tables 1 and 2, the yarns and fabrics for airbags obtained in Examples 1 to 9 were all excellent as airbag fabrics in terms of excellent mechanical properties such as tensile strength and air permeability. It has properties and storability, and is also excellent in impact resistance.

On the other hand, Comparative Example 1 not satisfying the requirements of the present invention
The yarns and fabrics for airbags obtained in Nos. To 5 do not satisfy at least one property of air permeability, flexibility, and shock absorption resistance.

[0061]

As described above, the yarn for an airbag of the present invention is flexible, has high toughness, and has an appropriate confounding strength. Further, the airbag fabric of the present invention has low air permeability, excellent flexibility and storage properties, which cannot be achieved by conventional techniques, and also has excellent shock absorption resistance. Therefore, according to the present invention, it is possible to increase the reliability of the airbag as a safety device and provide a compact airbag device.

[Brief description of the drawings]

FIG. 1 is an explanatory view showing an example of a method for producing a yarn for an airbag of the present invention.

FIG. 2 is an explanatory view showing a method of folding an airbag.

FIG. 3 is an explanatory view showing a method for measuring the shock absorption resistance of the airbag fabric of the present invention.

[Explanation of symbols]

 1: Yarn 2: Cooling unit 3: Spinning duct 4: Oil supply device 5, 6: Take-up roller 7: Yarn supply roller 8: First stretching roller 9: Second stretching roller 10: Tension adjusting roller 11: Entangling device 12, 12 ': Yarn path regulation guide 13: Winding machine I: Airbag II: Folding direction III, IV: Folded airbag A: Airbag B: Rubber balloon C: Pendulum

Continued on the front page F term (reference) 3D054 CC26 4L035 AA08 BB36 BB65 BB88 BB89 BB91 DD20 EE06 EE08 EE20 HH10 4L048 AA24 AA34 AA42 AA46 AA48 AA49 AA50 AB07 AB08 AB11 AC09 AC10 AC11 BA02 CA00 CA01 CA02

Claims (4)

[Claims] 1. A yarn for an airbag containing a polyamide multifilament as an essential component, comprising:
A yarn for an airbag, which satisfies conditions (1) to (7) at the same time. (1) The relative viscosity of 96% sulfuric acid of the yarn is 3.5 or more. (2) The fineness of a single yarn is 3.3 dtex or less. (3) The total fineness of the yarn is 200 to 700 dtex. (4) The strength of the yarn is 6. 5 cN / dtex or more (5) Elongation of yarn is 27% or more (6) Boiling water shrinkage of yarn is 6% or less (7) Stress at 10% elongation of yarn is 3.6 cN / dtex
Less than 2. A fabric for an airbag, wherein the raw yarn for an airbag according to claim 1 is used for both or one of a warp and a weft constituting the fabric for an airbag. 3. The fabric has a tensile strength in the warp and weft directions of at least 500 N / cm and a tensile elongation of 28%.
The fabric for an airbag according to claim 2, wherein: 4. The warp and / or weft entanglement number is 5 /
m, the total fineness of the warp is D1 (dtx), the weaving density is N1 (book / 2.54 cm), and the total fineness of the weft is D2.
(Dtx), when the weaving density is N2 (lines / 2.54 cm), (D1 × 0.9) ^1/2 × N1 + (D2 × 0.
9) Cover factor expressed by ^1/2 x N2 is 1500
Woven in the range of ~ 2300 with a breathability of 0.5c
The airbag fabric according to claim 2, wherein the fabric is c / cm ² / sec or less.