JP2001329468A - Base fabric for air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide the subject lightweight base fabric soft in feeling, having fundamental performances including uniform low air permeability and low- temperature characteristics and excellent in frayproofness as well, and to provide air bags using the above base fabric. SOLUTION: This base fabric for air bags is such as to have a substantially continuous coating film formed by coating a resin composition on at least one side of a synthetic fiber fabric and 0.001-0.5 mL/cm2.s in air permeability; wherein the resin composition is based on a polyurethane resin blend comprising 100 pts.wt. of a polycarbonate-based polyurethane resin and 1-10 pt(s).wt. of a polyether-based polyurethane resin (on a solid basis), and in coating the resin composition, its coating amount is set to be 3-10 g/m2 (on a solid basis).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a base fabric and an air bag used for an air bag, and more particularly, to a base fabric for an air bag having a light weight, a soft feel, a fraying preventing property and an extremely low air permeability. And an airbag.

[0002]

2. Description of the Related Art An airbag that absorbs an impact to protect the occupant in the event of a vehicle collision is manufactured by using an airbag base fabric and sewing it to a bag. As such a base fabric for an airbag, chloroprene, chloroprene, and the like are added to one surface of a synthetic fiber woven fabric using nylon 66 or nylon 6 filament yarn to add performance such as heat resistance, flame retardancy, and low air permeability. An elastomer such as silicone rubber was applied, laminated, cut and used, but the texture became coarse and hard, and the occupant's face was scratched when the airbag was deployed, and a large capacity was required for storage. was there.

[0003] As airbags have become widely used, there has been an increasing demand for lower prices and module covers to be reduced, and high-density base fabrics have been used in order to use uncoated base fabrics as base fabrics for airbags. However, there were disadvantages in terms of heat resistance and uniform low air permeability. Therefore, a base cloth that coats one surface of a synthetic fiber but has a good texture and satisfies uniform performance such as low air permeability is required instead of an uncoated base cloth.

Japanese Patent Application Laid-Open No. 9-240405 discloses a base fabric for an airbag in which fibers are filled with a coating made of a thermoplastic resin having an average thickness of 10 μm or less and a softening point of 120 ° C. or more. This technology can be achieved if the fibers are only joined on the surface of the yarn if it is a woven yarn, and if only the joint between the fibers and the fibers on at least one surface is joined if it is a nonwoven fabric. Therefore, if applied in a small amount to satisfy the texture, lightness, and low cost, the thickness of the film formed on the fiber surface cannot be made uniform, and The film was not formed sufficiently to join the intersections of the yarns. For this reason, stress concentrates on a portion where the thickness of the film is thin, peeling occurs between the fiber and the film, and the antifraying property and the fiber opening prevention property by the wind pressure are poor, and the uniform low air permeability is impaired. As a result, there is room for improvement in the uniformity of the quality of the airbag.

[0005]

SUMMARY OF THE INVENTION In view of the above situation, the present invention is light in weight, soft in texture, has uniform basic properties such as low air permeability and low temperature characteristics, and is excellent in anti-fraying properties. An object of the present invention is to provide an airbag base fabric and an airbag using the same.

[0006]

Means for Solving the Problems The inventors of the present invention select various coating agents to be applied to a base cloth, and can achieve a coating having a thickness as small as not to impair the feeling, and have a uniform and sufficient low air permeability. The present inventors have discovered a coating agent for a base fabric for an airbag, which has basic properties such as temperature and low-temperature characteristics and can be applied without fear of infiltration into fibers, and completed the present invention.

That is, the present invention has a substantially continuous coating film formed by applying a resin composition on at least one surface of a synthetic fiber woven fabric, and has a permeability of 0.1.
001 to 0.5 cm ³ / cm ² / s, wherein the resin composition comprises 100 parts by weight of a polycarbonate-based polyurethane resin and 1 to 10 parts by weight of a polyether-based polyurethane resin (solid content). (Ratio) as a main component, and is a base fabric for an airbag, wherein the application amount is 3 to 10 g / m ² (solid content) in the application.
Hereinafter, the present invention will be described in detail.

The airbag fabric of the present invention has a substantially continuous coating film formed by applying a resin composition to at least one surface of a synthetic fiber fabric. The synthetic fiber fabric is not particularly limited, and a synthetic fiber fabric usually used as a base fabric for an airbag can be used. For example, polyamide, polyester, polyethylene, vinylon, vinylidene, acrylic, polyurethane, aramid, polynosic, rayon And other woven patterns having various woven patterns commonly used. Among these, plain fabrics are preferred because of their excellent performance such as strength, and the present invention can be suitably applied.

The resin composition of the present invention is mainly composed of a polyurethane resin mixture comprising 100 parts by weight of a polycarbonate polyurethane resin and 1 to 10 parts by weight (solid content) of a polyether polyurethane resin. In the above resin composition, the polycarbonate polyurethane resin and the polyether polyurethane resin can be used alone or in combination of two or more.

The polycarbonate-based polyurethane resin is not particularly limited as long as it is a polymer obtained by a polymerization reaction between polycarbonate diol and polyisocyanate. The polycarbonate diol is not particularly limited, and examples thereof include those obtained by a reaction between a diol and a cyclic carbonate, those obtained by a reaction between a polyol and phosgene, and those obtained by a transesterification reaction of diphenyl carbonate. The diol is not particularly limited, and examples thereof include those used in ordinary polyurethane resins. Examples thereof include aliphatic diols and aromatic diols. These may be used alone or in combination of two or more. Can be used in combination. The molecular weight of the polycarbonate diol is not particularly limited, either.
Generally, about 0 is used.

Examples of the polyisocyanate include those used for ordinary polyurethane resins. Examples thereof include tolylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and the like.
Examples thereof include aromatic diisocyanates such as hydrogenated tolylene diisocyanate and hydrogenated diphenylmethane diisocyanate, and aliphatic diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate. These may be used alone or in combination of two or more. Can be.

The polyether-based polyurethane resin used in the present invention is a polymer obtained by a polymerization reaction between a polyether polyol and a polyisocyanate. The polyether polyol is not particularly limited, and examples thereof include polyethylene glycol, polypropylene glycol, polytetramethylene ether glycol, various modified polyether polyols, and the like. These may be used alone or in combination of two or more. be able to.

Examples of the polyisocyanate include those used in ordinary polyurethane resins. Examples thereof include aromatic diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated tolylene diisocyanate, and hydrogenated diphenylmethane diisocyanate. Aliphatic diisocyanates, such as hexamethylene diisocyanate and isophorone diisocyanate, can be used.
More than one species can be used in combination. In the above resin composition, the weight average molecular weight (Mw) of the polycarbonate-based polyurethane resin is not particularly limited.
It is preferably from 10,000 to 500,000. 10
If it is less than 000, performance such as strength may be inferior, and if it exceeds 500,000, it may be difficult to prepare a polymer. The weight average molecular weight (Mw) of the polyether polyurethane resin is not particularly limited,
For example, it is preferably 2000 to 100,000. If it is less than 2,000, the property of thickening the resin composition may be reduced, and if it exceeds 100,000,
There is a possibility that it becomes difficult to prepare an aqueous polymer. More preferably, it is 5,000 to 50,000.

[0014] In the polyurethane resin mixture of the present invention, the polycarbonate-based polyurethane resin is N,
Instead of dissolving in an organic solvent such as N-dimethylformamide (DMF) or a mixed solvent of DMF and methyl ethyl ketone (MEK), disperse in a dispersion containing an aqueous dispersant or emulsifier, or use a self-dispersion type It is preferable to use as a water-dispersible resin. By doing so, effects unique to the present invention can be obtained.

In the polyurethane resin mixture of the present invention, the polyether-based polyurethane resin is DMF,
Instead of dissolving in an organic solvent such as a mixed solvent of DMF and MEK, the water-soluble polyether-based polyurethane resin containing the necessary amount of polyethylene glycol to make it water-soluble is included in the component of the polyether polyol. preferable. By doing so, the resin composition has a property of increasing the viscosity, and the effects unique to the present invention can be obtained.

The polyurethane resin mixture of the present invention comprises the above-mentioned polycarbonate-based polyurethane resin 1 in a solid content ratio.
The polyether-based polyurethane resin is used in an amount of 1 to 10 parts by weight based on 00 parts by weight. If the amount is less than 1 part by weight, the resin composition cannot be appropriately thickened, so that it is difficult to form a substantially continuous coating film. If it exceeds 10 parts by weight, the viscosity of the obtained resin composition becomes too high, making it difficult to make the coating film thinner, and making the resin composition difficult to handle. More preferably, the polyether polyurethane resin is 3 to
7 parts by weight, more preferably 4 to 6 parts by weight.

The resin composition of the present invention is mainly composed of the above polyurethane resin mixture. Here, “mainly” means that the above-mentioned polyurethane resin mixture is used as a main resin component, and it means that other resin components may or may not be additionally contained.

Since the resin composition of the present invention has the above-mentioned constitution, when a water-dispersible resin is used as the polycarbonate-based polyurethane resin, it is far more expensive than when a normal alkali-thickened polyacrylate copolymer is used. It is possible to exhibit a gradual increase in viscosity, and to obtain a viscosity suitable for coating forming a substantially continuous coating film. This fact has been found for the first time by the present inventors. In addition, the substantially continuous coating film means a coating film continuously formed with a constant thickness so as to realize uniform basic performance such as low air permeability and low-temperature characteristics.

In general, since an organic solvent has high permeability to a synthetic fiber fabric, when a coating agent is applied in a state of being dissolved in an organic solvent, the resin composition penetrates between the fibers, so that the fiber surface is covered. It is difficult to form a substantially continuous coating film. Therefore, when a water-based resin composition is used, permeability between fibers is suppressed, and a coating film can be formed on the fiber portion. However, texture and lightness,
There has been no polyurethane resin that is a water-based resin composition and can exhibit appropriate viscosity when the coating amount is set to be small in order to improve the storability, cost effectiveness, safety, and the like. In other words, even in the case of an aqueous polyurethane resin composition, in order to obtain uniform performance such as low air permeability and low-temperature characteristics, the thickness of the coating film formed on the fiber surface is uniform with a normal thickening method. And
In the case of plain weave, a coating film could not be formed sufficiently even between the intersections of the yarns.

As described above, the present inventors have found a combination of polyurethane resins that can obtain the appropriate viscosity required for the base fabric for an airbag even with an aqueous resin. , Light weight, soft texture, uniform basic performance such as low air permeability and low temperature characteristics,
In addition, the base fabric for an airbag of the present invention, which is excellent in anti-fraying properties, has been completed. The reason why the present invention exerts the above-mentioned effects is not necessarily clear, but, for example, (1) by combining a polycarbonate-based polyurethane resin with a polyether-based polyurethane resin, the viscosity at the time of coating can be adjusted appropriately, and the coating amount can be reduced. Even if you set less,
The viscosity when applied to the fiber surface is to form a coating film having a uniform thickness, and that the coating film can be adequately formed between the intersections of the yarns in plain weave, (2) Since a substantially continuous coating film is formed as described above, the yarns and the intersections of the yarns are uniformly joined by the coating film, and there is no place where stress concentrates. In addition, gas barrier properties can be exhibited uniformly,
(3) Since the polycarbonate polyurethane resin and the polyether polyurethane resin are the same polyurethane resin and the viscosity can be adjusted without affecting the properties of the polyurethane resin, the performance in the coating film is sufficient and uniform. (4) The use of polycarbonate-based polyurethane resin improves the low-temperature properties, and the use of a water-dispersed resin makes it easier to form a coating film. Can be

In the present invention, a coating film is formed by applying the above resin composition to at least one surface of a synthetic fiber fabric. It may be applied on both sides, but usually it is applied on one side to form a coating film. The one surface is an inner surface when sewing the airbag. In the application, the application amount of the resin composition is 3 to 10 g / m ² (solid content). 3g /
If it is less than m ² , sufficient low air permeability cannot be obtained,
If it exceeds 10 g / m ² , the texture will decrease and
There is a possibility that lightness, storability, inexpensiveness, safety, etc. may be reduced. The fact that the coating amount can be set to 3 to 10 g / m ² (solid content) is also an effect caused by successfully selecting the configuration of the resin composition.

The airbag fabric of the present invention has an air permeability of 0.001 to 0.5 cm ³ / cm ² / s. The air permeability can be measured as follows. That is, 100 mm × 150 mm of the base cloth was sampled as a test piece, and the amount of air (cm ³⁾ that passed through the test piece per second per unit area at a differential pressure of 125 Pa using a test device based on the Frazier type shown in FIG. ) And its numerical value (cm
³ / cm ² / s) is defined as the air permeability. The air permeability is 0.0
Base fabrics of less than 01 cm ³ / cm ² / s cannot usually be made. The air permeability is 0.5 cm ³
If it exceeds / cm ² / s, the object of the present invention cannot be achieved.

The resin composition used for the airbag base fabric of the present invention preferably contains a flame retardant in order to impart the necessary flame retardancy to the airbag base fabric of the present invention. And a flame retardant in an amount of 5 to 40% by weight. If the content is less than 5% by weight, the flame retardant effect cannot be confirmed. If the content exceeds 40% by weight, the flame retardant effect can be sufficiently exhibited, but is economically disadvantageous. More preferably, 1
0 to 30% by weight.

Examples of the flame retardant include commonly used flame retardants, such as phosphorus-based flame retardants, halogen-based flame retardants, and inorganic flame retardants. These may be used alone or in combination of two or more. These can be used in combination. The flame retardancy required for an airbag base fabric is, for example, a flame retardant effect to such an extent that the airbag can be deployed without burning or breakage even when the airbag is deployed due to a heat rise caused by heat generated by the inflator. Means

The resin composition used in the base fabric for an airbag of the present invention preferably contains a blocked isocyanate in order to improve the adhesion between the coating film and the surface of the synthetic fiber fabric. Is preferably contained in an amount of 0.1 to 3% by weight.
If it is less than 0.1% by weight, the effect of improving the adhesiveness cannot be confirmed, and if it exceeds 3% by weight, the texture of the obtained airbag base fabric may be impaired. More preferably, it is 0.5 to 2% by weight.

The above blocked isocyanate can be obtained by reacting a blocking agent only with polyisocyanate, or by reacting a blocking agent with a urethane prepolymer obtained by reacting polyisocyanate and polyol.

The polyisocyanate is not particularly restricted but includes, for example, aromatic diisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, hydrogenated tolylene diisocyanate and hydrogenated diphenylmethane diisocyanate, and aliphatic diisocyanates such as hexamethylene diisocyanate and isophorone diisocyanate. And diisocyanates and the like.
More than one species can be used in combination.

The polyol is not particularly limited.
For example, ethylene glycol, diethylene glycol,
Examples thereof include low-molecular-weight polyols such as glycerin, trimethylolpropane, and pentaerythritol; polyphenols such as bisphenol A and bisphenol F; and propylene oxide adducts thereof. The blocking agent is not particularly limited, and includes, for example, ε-caprolactam, oxime, phenol, alcohol and the like.

The resin composition used in the base fabric for an airbag of the present invention contains a pigment in an amount of 0.1 to make it easy to visually identify the surface on which the resin composition has been applied.
It is preferable to contain 1 to 3% by weight. In the step of sewing the airbag, usually, after sewing the base fabric for the airbag, the surface on which the resin composition is applied is sewn with the inside thereof being inside, so that it is easy to visually determine which surface is applied. The ability to do so is necessary for the process to proceed accurately and quickly. If the amount of the pigment is less than 0.1% by weight, it is not easy to visually determine the surface on which the resin composition has been applied. If the amount of the pigment exceeds 3% by weight, the effect of the present invention is impaired. May be More preferably, it is 0.5 to 2% by weight.

The pigment is not particularly limited, and is preferably a water-dispersible pigment in view of the properties of the resin composition. The pigment may be an organic pigment or an inorganic pigment. Since it is only identification of the surface, a simple black pigment may be used, for example, carbon black or the like.

The synthetic fiber woven fabric used for the airbag base fabric of the present invention has a cover factor of 1500 to 2000.
It is preferred that The cover factor is defined as the total warp fineness is D1, the warp density is N1, and the total weft fineness is D1.
2. When weft density is N2, it means the numerical value represented by (D1) ^1/2 × N1 + (D2) ^1/2 × N2, which is a measure of whether the fibers of the woven fabric are dense or sparse. It is. The synthetic fiber woven fabric used for the airbag base fabric of the present invention has the above-mentioned cover factor of 1500.
Even with a relatively sparse woven fabric of about 2000, sufficient low air permeability and reliable anti-fraying properties can be obtained as a base cloth, and therefore, the texture is sufficiently soft, and
There is an advantage that a low-cost product can be manufactured.

The method for applying the resin composition to at least one surface of the synthetic fiber woven fabric for producing the airbag base fabric of the present invention is not particularly limited as long as it can be applied uniformly. Examples thereof include a method using a coater, a reverse coater, a knife coater, and the like.

According to the present invention, it is lightweight, has good texture, has basic properties such as uniform low air permeability and low temperature characteristics, and
An airbag fabric excellent in anti-fraying properties can be obtained, but an airbag manufactured by applying a normal method using such an airbag fabric has extremely excellent uniform quality. And are particularly useful in the automotive industry. Such an airbag is also one of the present invention.

[0034]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited to these examples.

Example 1 100 parts by weight of an aqueous dispersion of a polycarbonate-based polyurethane resin (solid content: 40%), 10 parts by weight of an aqueous solution of a polyether-based polyurethane resin (solid content: 17.5%), a halogen-based flame retardant and an inorganic-based 20 parts by weight of an aqueous dispersion of a mixture with a flame retardant (solid content: 77%) and 0.5 parts by weight of water-dispersible carbon black were added to 150 parts by weight of water, mixed, and mixed.
The viscosity was adjusted so as to be 18 Pa · s to obtain a resin composition. 18. Latitude and latitude are 470 dtex and density is 18.
1 line / cm, 18.1 lines / cm, cover factor 1
885 was coated on one side of a nylon 66 plain fabric using a knife coater so that the coating amount was 8 g / m ² (solid content) to form a coating film. The air permeability and pure bending stiffness of this product were measured as follows. Further, in order to see the fraying prevention after cutting when this was used as a base fabric for an airbag, it was actually cut and the presence or absence of the fray was visually observed. The results are shown in Table 1.

[0036]Air permeability  According to JIS L 1096, the effective part and the end of the substrate
Approximately 150mm x 1
A 50 mm test piece was collected and converted into a Frazier type shown in FIG.
Using a test device based on
Air volume per second per unit area (cm^Three / Cm^Two 
/ S).

[0037]Pure bending stiffness  KES-FB2 (trade name, manufactured by Kato Tech Co., Ltd., pure music
Using a fixed chuck and a moving chuck.
The moving chuck is held in a circular arc shape.
0.50cm^-1/ S and move at that time.
Luk was detected on the fixed chuck side to determine the pure bending stiffness.
Note that the measured curvature K is | K | ≦ 2.5 cm ^-1So that
I made it. Pure bending stiffness means that the bending moment depends on the position.
It is the rigidity of the bending that does not change.

Example 2 Polycarbonate polyurethane aqueous dispersion resin (solid content:
40%), 100 parts by weight of a polyether-based polyurethane water-soluble resin (solid content: 17.5%), 10 parts by weight, an aqueous dispersion of a mixture of a halogen-based flame retardant and an inorganic flame retardant (solid content:
Nylon 6 in the same manner as in Example 1 except that a resin composition obtained by adding and mixing 20 parts by weight of water and 1 part by weight of a water-dispersible blocked isocyanate to 150 parts by weight of water was used.
A coating film was formed on one side of 6 plain fabrics. The performance of this was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Example 3 Polycarbonate polyurethane aqueous dispersion resin (solid content:
40%) 100 parts by weight, polyether polyurethane water
10 parts by weight of soluble resin (solid content: 17.5%), dispersible in water
1 part by weight of blocked isocyanate, water-dispersible carbon
Add 0.5 parts by weight of rack to 150 parts by weight of water and mix
Using the obtained resin composition, a coating amount of 5 g / m ^Two Other than
On one side of nylon 66 plain woven fabric in the same manner as in Example 1.
A coating film was formed. Example of the performance of this
Evaluation was performed in the same manner as in Example 1. The results are shown in Table 1.

Example 4 Polycarbonate polyurethane aqueous dispersion resin (solid content:
40%), 100 parts by weight of a polyether-based polyurethane water-soluble resin (solid content: 17.5%), 10 parts by weight, an aqueous dispersion of a mixture of a halogen-based flame retardant and an inorganic flame retardant (solid content:
77%), in the same manner as in Example 1 except that a resin composition obtained by adding and mixing 20 parts by weight, 1 part by weight of a water-dispersible blocked isocyanate, and 0.5 part by weight of a water-dispersible carbon black was used. A coating film was formed on one side of nylon 66 plain fabric. The performance of this was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 1 On one side of the same nylon 66 plain woven fabric used in the examples,
Using a knife coater, a silicone coating agent was applied to a coating amount of 28 g / m ² (nonvolatile content) to form a coating film. The performance of this was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 2 The warp and weft were 470 dtex and the density was 20.1 threads / c.
m, 20.1 wefts / cm, a cover factor of 872, without forming a coating film on nylon 66 plain woven fabric,
The performance of this uncoated base fabric was evaluated in the same manner as in Example 1. The results are shown in Table 1.

Comparative Example 3 100 parts by weight of an aqueous dispersion of a polycarbonate-based polyurethane resin (solid content: 40%), 5 parts by weight of a copolymer water-soluble resin of a polyacrylic ester for thickening an alkali, a halogen-based flame retardant and an inorganic resin Aqueous dispersion of a mixture with a flame retardant (solid content:
(77%), 20 parts by weight of water-dispersible blocked isocyanate, 1 part by weight of water-dispersible carbon black and 0.5 part by weight of water-dispersible carbon black are added to 150 parts by weight of water, mixed, and mixed with ammonia water (28%).
%) To obtain a resin composition by adjusting the viscosity so as to be 12 to 18 Pa · s. One side of the same nylon 66 plain woven fabric as that used in the examples was coated with a knife coater to a coating amount of 8 g / m ² (solid content) to form a coating film. The performance of this was evaluated in the same manner as in Example 1. The results are shown in Table 1.

[0044]

[Table 1]

In Examples 2 to 4, the peel strength was about 2
0% improvement, and in Examples 1, 2 and 4, the flame retardant standard can be achieved, and in Examples 1, 3 and 4, the airbag which can easily recognize the coated surface Base cloth was obtained. As is evident from Table 1, the coating of the present invention can provide a base fabric for an airbag having the same air permeability, light weight, thin thickness, and low pure bending stiffness as compared with the conventional silicone coating. all right. As described above, since the base fabric is thin and the base fabric is soft (pure bending rigidity is low), the airbag can be folded compactly, and the lightweight and soft base fabric is close to the occupant when the airbag is deployed. In this case, the airbag is less likely to be repelled by the occupant before the airbag is fully deployed. On the other hand, in the uncoated base cloth, even if the density is increased in order to suppress the air permeability suitable for the airbag, the air permeability cannot be sufficiently suppressed and fraying occurs. Such fraying requires an expensive process such as fraying by heat during the production of the airbag, which increases the cost. It can be understood from Table 1 that increasing the density in order to realize low air permeability results in an increase in thickness and weight and a worsening of the texture compared to the product of the present invention. Therefore, the base fabric for an airbag of the present invention is a suitable base fabric as a material for an airbag that can provide an inexpensive airbag that is lightweight, compact, and has little impact upon deployment.

5 to 7 show the SE of the cross section of the nylon 66 plain woven fabric on which the coating film was formed in Example 4.
The M photograph was shown. 8 to 10 show SEM photographs at intersections of yarns of the woven fabric. 11 to 13 show SEM photographs at the intersections of the yarns of the nylon 66 plain woven fabric on which the coating film was formed in Comparative Example 3.
In these figures, the magnification is increased in the order of FIGS. 5 to 7, FIGS. 8 to 10, and FIGS. 11 to 13. The particulate matter in the coating film shown in FIGS. 5 to 13 is a flame retardant present in the coating film.

As apparent from FIGS. 5 to 10, the coating in the present invention forms a substantially continuous coating film, and from FIGS. 8 to 10, the coating film is also laminated between the intersections of the fabric. This corresponds to FIG.
It can be observed well at the locations b and c and the location d. On the other hand, as is apparent from FIGS. 11 to 13, in the coating by alkali thickening in the comparative example, the coating film is not formed substantially continuously. Therefore, according to the present invention, it was found that a substantially continuous coating film was formed and a uniform quality airbag fabric could be provided.

[0048]

The airbag fabric of the present invention has the following effects. That is, in a coating base fabric that has been conventionally applied and laminated with chloroprene, silicone rubber, or the like, as shown in FIG. 2, there is a coating film 2 that covers the surface of a synthetic fiber woven fiber 1 with a thick elastomer. Although it was satisfactory enough in terms of low air permeability, heat resistance, flame retardancy, etc., the base fabric itself was hard and inferior in storage, and texture and lightness,
It was also inexpensive.

In order to solve this problem, an uncoated base fabric was used, but the disadvantages in terms of heat resistance and low air permeability could not be wiped out.
A base fabric in which the space between the fibers is filled with a coating made of a specific thermoplastic resin, as disclosed in Japanese Patent No. 0405, has been devised. However, when this coating is applied with a small coating amount that satisfies the feeling, lightness, and low cost, a coating film having a sufficient thickness only in the gap between the fibers 1 as shown in FIG. No. 2 was intended to be present, and since the coating film on the fiber portion was thin, stress was concentrated on a thin portion of the film, and the fibers could be separated and separated. Further, as shown in FIGS. 11 to 13, the coating film could not be formed sufficiently between the intersections of the woven yarns, and uniform low air permeability could not be obtained. On the other hand, when the amount of application was increased, as shown in FIG. 2, the coating film 2 became thicker, so that it was not possible to satisfy the feeling, lightness, and low cost.

The airbag fabric of the present invention is shown in FIGS.
As shown in FIGS. 10 to 10, the coating agent 1 forms a substantially continuous coating film on the surface of the fiber 2 while maintaining an appropriate thinness, whereby low air permeability (gas barrier properties) and Excellent performance at low temperatures, etc., all features and properties required for airbag fabrics, such as light weight, anti-fraying, storage, safety, low cost, and uniform quality. The obtained base fabric can be obtained. An airbag using such an airbag base fabric of the present invention has extremely excellent and uniform quality, and is particularly useful in the automobile industry.

[Brief description of the drawings]

FIG. 1 is a schematic cross-sectional view showing a surface state of a base fabric for an airbag of the present invention.

FIG. 2 is a schematic cross-sectional view showing a surface state of a conventional coated airbag fabric.

FIG. 3 is a schematic sectional view showing a surface state of a base fabric for an airbag according to the technique described in Japanese Patent Application Laid-Open No. 9-240405.

FIG. 4 is a diagram illustrating a Frazier-type test apparatus for measuring air permeability according to the present invention.

FIG. 5 is an SEM photograph of a cross section of a nylon 66 plain fabric on which a coating film is formed in Example 4.

FIG. 6 is an enlarged view of the SEM photograph in FIG.

FIG. 7 is a further enlarged SEM photograph of FIG.

FIG. 8 is a SEM photograph at the intersection of yarns of a nylon 66 plain woven fabric having a coating film formed thereon in Example 4.

FIG. 9 is an enlarged view of the SEM photograph in FIG.

FIG. 10 is a further enlarged SEM photograph of FIG.

FIG. 11 is a SEM photograph at the intersection of woven yarns of a nylon 66 plain woven fabric on which a coating film is formed in Comparative Example 3.

FIG. 12 is an enlarged view of the SEM photograph in FIG. 11;

FIG. 13 is a further enlarged SEM photograph of FIG.

[Explanation of symbols]

Reference Signs List 1 Fiber 2 Coating film a, b, c Location where the coating film can be clearly observed between the intersections of the fabric d Cross section of the location where the coating film can be clearly observed between the intersections of the fabric

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Masanori Uemoto 15th, Kichijoin Ochiaicho, Minami-ku, Kyoto 1st Race Co., Ltd. (72) Inventor Masaharu Wada 15th, Kichijoin Ochiaicho, Minami-ku, Kyoto 3D054 CC26 CC45 FF01 FF03 FF13 FF14 FF18 FF20 4L033 AA04 AB01 AB05 AC15 CA50 CA70 4L048 AA24 AB07 BA01 BA02 CA11 CA15 DA25 EB00

Claims (8)

[Claims] 1. A synthetic fiber woven fabric having a substantially continuous coating film formed by applying a resin composition to at least one surface of a synthetic fiber woven fabric, and having an air permeability of 0.001 to 0.5.
a base fabric for an airbag having a size of cm ³ / cm ² / s,
The resin composition comprises 100 parts by weight of a polycarbonate-based polyurethane resin and 1 part of a polyether-based polyurethane resin.
An airbag mainly comprising a polyurethane resin mixture consisting of 10 to 10 parts by weight (solid content ratio), wherein the application amount is 3 to 10 g / m ² (solid content). Base cloth. 2. The airbag fabric according to claim 1, wherein the polycarbonate polyurethane resin is a water-dispersible resin. 3. The airbag base fabric according to claim 1, wherein the polyether-based polyurethane resin is a water-soluble resin and has a property of thickening the resin composition. 4. The resin composition further comprises a flame retardant of 5 to 40.
2. The composition according to claim 1, wherein
4. The airbag fabric according to 2 or 3. 5. The base fabric for an air bag according to claim 1, wherein the resin composition further contains 0.1 to 3% by weight of a blocked isocyanate. 6. The resin composition further comprises 0.1 to 3 pigments.
2. The composition according to claim 1, wherein
The base fabric for an airbag according to 2, 3, 4, or 5. 7. The synthetic fiber woven fabric has a cover factor of 15
The number is from 2000 to 2000.
7. The airbag fabric according to 3, 4, 5 or 6. 8. An airbag, wherein the airbag base fabric according to claim 1, 2, 3, 4, 5, 6, or 7 is used.