JPH11107171A - Laminated fabric and air bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a laminated cloth having excellent adhesiveness between a resin and a woven fabric, no adhesion between woven fabrics by an additive and excellent weather resistance by a simple production method, to provide a method for producing the laminated cloth and to obtain an air bag. SOLUTION: A polyurethane resin containing a polyester polyol containing >=50 wt.% of an ester unit of a trimethyl-1,6-hexanediol and an aliphatic dicarboxylic acid and having 500-5,000 number-average molecular weight and a diisocyanate compound is laminated to at least one side of a filament woven fabric made of a synthetic resin to give the objective laminated fabric.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated fabric obtained by coating a woven fabric with a specific polyurethane resin and an airbag using the same.
The present invention relates to a laminated fabric obtained by coating a synthetic resin filament woven fabric with a polyurethane resin using an aliphatic polyester polyol, a method for producing the same, and a vehicle airbag using the same.

[0002]

2. Description of the Related Art In recent years, airbags for ensuring the safety of occupants in automobiles have rapidly become widespread. In the event of an automobile collision, the center receives the shock of a collision and generates high-temperature, high-pressure gas, which causes the airbag to inflate instantaneously. It protects the face and the head, and protects the head and the built-in parts against side collision.
Conventionally, airbags are polyester, 6,6 nylon, 6
Using a high-strength plain woven fabric made of 400-1000 denier filament yarn made of synthetic resin such as nylon, the inner surface, outer surface or both surfaces are heat-resistant, weather-resistant, flame-retardant, air-blocking, etc. In order to improve the weight, a bag which is formed in a bag shape with a base fabric formed by applying and laminating a synthetic rubber or an elastomer such as chloroprene rubber, chlorosulfonated polyolefin, or silicone rubber, and which can be folded lightly and compactly is required.

[0003] Japanese Patent Application Laid-Open No. 2-270654 discloses an airbag in which a thin film of silicon rubber is formed on a woven fabric. However, silicon rubber has excellent heat resistance and weather resistance, but it is difficult to laminate it on a woven fabric, and the resulting film becomes moldy and has a problem in terms of life, and pinholes occur. There was a problem that it was easy.

Japanese Patent Application Laid-Open No. 4-97842 discloses an airbag in which a woven fabric is laminated with a polyolefin resin such as an ethylene-propylene copolymer, an ethylene-vinyl acetate copolymer, or an ionomer resin. However, these resins did not have sufficient adhesiveness to a woven fabric, weather resistance, and inflatability of an airbag.

[0005] Japanese Patent Application Laid-Open No. 4-143145 discloses a polyurethane obtained from a polyol-containing vinyl chloride copolymer and an isocyanate in a woven fabric. But,
In these resins, a plasticizer is added to contain the vinyl chloride copolymer, and there is a problem that the plasticizer comes out and sticks to each other when the airbag is stored in a stored state for a long time. .

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a laminated fabric which has good adhesiveness between a resin and a woven fabric, has no adhesion between woven fabrics due to additives, has excellent weather resistance, and has a simple production method. , A manufacturing method thereof, and an airbag using the same.

[0007]

Means for Solving the Problems In view of the above problems, the present inventors have intensively studied various laminated materials, and as a result, by using a polyurethane using a specific polyester polyol as the laminated material, the airbag was improved. The present invention has been found to be capable of easily obtaining a high-strength airbag having a small layer thickness, light weight, and excellent extensibility, adhesion to a woven fabric, weather resistance, and pinhole resistance, no swelling due to additives, and a thin layer thickness. Was completed.

That is, the present invention relates to trimethyl-1,6-
Containing at least 50% by weight of an ester unit of a hexanediol and an aliphatic dicarboxylic acid, and having a number average molecular weight of 500 to
The present invention relates to a laminated cloth obtained by laminating a polyurethane resin comprising 5,000 polyester polyols and a diisocyanate compound on at least one surface of a synthetic resin filament fabric. The present invention also relates to a laminate cloth wherein the aliphatic dicarboxylic acid is adipic acid. Further, the present invention relates to a laminate cloth in which the polyurethane resin contains a flame retardant. The present invention relates to a vehicle airbag comprising the above-mentioned laminated cloth.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The laminated fabric of the present invention comprises a woven fabric and a polyurethane resin coated on one or both sides of the woven fabric. The polyurethane resin may be laminated on the woven fabric in a planar manner, or may be impregnated and coated between filament yarns of the woven fabric. First, the woven fabric will be described. As a woven fabric, a homopolyester such as polyethylene terephthalate, a copolyester in which an acid component constituting a repeating unit of a polyester is copolymerized with an aliphatic dicarboxylic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid or adipic acid, 6-nylon, 6-nylon, 12-nylon, 4,6-nylon and their nylon copolymers, polyamides obtained by copolymerizing nylon with polyalkylene glycol, dicarboxylic acid and amines, para-phenylene terephthalamide and aromatic ethers Aramid represented by polymerization, etc.
Sulfone resins such as paraphenylene sulfone and polysulfone, and synthetic fibers such as polyetherketone resin,
Continuous monofilament or multifilament yarns such as carbon fiber and glass fiber can be used.

As the filament yarn, a conventionally used filament having a thickness of 400 to 1000 denier is used. The weaving method for obtaining the woven fabric from the filament yarn is plain weaving, twill weaving, or the like. As woven cloth, the fabric weight is 5
0~250g / m ^2, the strength 150~1000kg / 3c
Those having an m width or the like are preferred.

Since the woven fabric is coated with a polyurethane resin, the filament yarn itself may contain various additives in a manufacturing process or a processing process. For example, a heat stabilizer, an antioxidant, a light stabilizer, a leveling agent, an antistatic agent, a plasticizer, a thickener, a pigment, a flame retardant and the like can be contained. Flame retardants and the like can be impregnated later into the woven fabric.

Next, a polyurethane resin to be coated on the woven fabric will be described. The polyurethane resin used in the present invention contains a polyurethane resin obtained by reacting a high molecular polyester polyol with a diisocyanate compound. The high molecular polyester polyol,
At least 3,3,5-trimethyl-1,6-hexanediol and / or 3,5,5-trimethyl-1,6
-Hexanediol (hereinafter referred to as trimethyl-1,
6-hexanediol (TMHDs)) and an aliphatic dicarboxylic acid, containing at least 50% by weight of ester units of the TMHDs and the aliphatic dicarboxylic acid, and having an alcoholic hydroxyl group at the end. Therefore, the high molecular polyester polyol used in the present invention includes (1) an aliphatic dicarboxylic acid and a polyester polyol of TMHD, and (2) an aliphatic dicarboxylic acid and TMH.
A polyester polyol of a mixture of D and another polyol, (3) a polyester polyol of an aliphatic dicarboxylic acid and another polyol, or a mixture of another polyester polyol and the polyester polyol of the above (1) or (2). .

The polyester polyol is preferably a high molecular weight polyester polyol having a number average molecular weight (in the present invention, the molecular weight is represented by a number average unless otherwise specified). If the molecular weight is less than 500, the solubility in a diluent is reduced, so that the coatability is poor and the
If it exceeds 00, the drying and blocking resistance will be insufficient.

The above-mentioned other polyols include (1)
Polyether polyols composed of polymers or copolymers such as ethylene oxide, propylene oxide and tetrahydrofuran; (2) glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4- Butanetriol, pentaerythritol, sorbitol, ethylene glycol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, pentanediol, hexanediol, octanediol, 1,4-
Saturated and unsaturated low molecular weight glycols such as butynediol, diethylene glycol, triethylene glycol, dipropylene glycol and the like can be mentioned. As the other polyester polyol, (3) a polyester obtained by ring-opening polymerization of a cyclic ester compound Polyols,
(4) Polycarbonate polyols, (5) Polybutadiene glycols, and glycols obtained by adding ethylene oxide or propylene oxide to bisphenol A.

The aliphatic dicarboxylic acids include adipic acid, phthalic anhydride, isophthalic acid, terephthalic acid, maleic acid, fumaric acid, succinic acid, oxalic acid, colonic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, Examples thereof include dibasic acids such as sebacic acid and acid anhydrides and acid chlorides corresponding thereto.

The polyurethane resin of the present invention may contain a low molecular weight polyol as a constituent component in addition to the high molecular weight polyester polyol. As a low molecular polyol,
Examples of the aliphatic dibasic acid ester of polytrimethylhexanediol, in particular, adipate or the above-mentioned various low-molecular polyols that can be used for producing a high-molecular polyol can be given. The amount of the low molecular polyol used is preferably 10% by weight or less of the high molecular polyol. If the use ratio exceeds 10% by weight, the adhesion of the obtained coating composition to the woven fabric and the solubility in the diluent are reduced.

The diisocyanate compound in the present invention refers to aromatic, aliphatic and alicyclic diisocyanates. Specifically, 1,5-naphthalenediisocyanate, 4,4′-diphenylmethane diisocyanate,
4,4′-diphenylmethane diisocyanate, 4,
4'-dibenzyl isocyanate, dialkyl diphenyl methane isocyanate, tetraalkyl diphenyl methane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, tolylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, 2,2 4-trimethylhexamethylene diisocyanate, 2,4,4
-Trimethylhexamethylene diisocyanate, tolidine diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4 '
-Diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, methylcyclohexanediisocyanate and the like. In order to laminate the outer surface of the woven fabric, diisocyanates in which an isocyanate group such as an aliphatic or alicyclic group is bonded to an aliphatic hydrocarbon are preferable from the viewpoint of weather resistance and the like.

In the present invention, a chain extender can be used in the polyurethane resin. As a chain extender, ethylenediamine, propylenediamine, hexamethylenediamine, diethylenetriamine, triethylenetetramine, isophoronediamine, dicyclohexylmethane-
4,4′-diamine can be exemplified. Diamines having a hydroxyl group in the molecule, for example, 2-hydroxyethylethylenediamine, 2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine,
2-Hydroxypropylethylenediamine, di-2-hydroxypropylethylenediamine and the like can also be used.

When the polyurethane resin of the present invention uses an amino group-containing compound as a chain extender, polymerization terminator or stabilizer, the obtained polyurethane resin has an amine value of 0 to 10 (KOH mg / g). Is preferably within the range. When the amine value is in this range, the adhesiveness to the woven fabric is excellent due to the amino group contained therein and the effect of the soft segment of trimethyl-1,6-hexanediol.

The polyurethane resin used in the present invention preferably has a number average molecular weight (Mn) in the range of 5,000 to 100,000. Number average molecular weight is 5,000
If it is less than 100%, the drying properties, blocking resistance and film strength of the coating composition are poor. On the other hand, if it exceeds 100,000, the viscosity becomes too high and the applicability deteriorates.

In the present invention, a flame retardant can be added to the polyurethane resin. As the flame retardant, a thiourea-based compound, a halogen-based organic compound, particularly a chlorinated polyolefin, a phosphorus-based organic compound, an inorganic-based flame retardant, and the like can be added. The chlorinated polyolefin is, for example, chlorinated ethylene homopolymer, propylene homopolymer, or a copolymer of such a monomer and another olefin-based monomer, and has a chlorine content of 1 to 60.
%, Especially 10 to 40% by weight is preferred. The chlorinated olefin has a number average molecular weight of 5,000 to 200,
000, especially 10,000-100,000 are suitable. Stereoregularity does not matter. The added amount of the chlorinated polyolefin is preferably polyurethane resin (1) / chlorinated polyolefin (2) = 5/95 to 95/5 (% by weight). The mixing ratio with the chlorinated polyolefin (2) can be set arbitrarily. Polyurethane resin and chlorinated polyolefin are inherently incompatible, but the composition used in the present invention is characterized by being a uniform and transparent solution because it uses a polyurethane resin composed of a specific polymer polyol. .

Examples of the method of applying the urethane resin and laminating by lamination include a method of applying and drying the solution of the urethane resin, a method of coating the urethane resin film by pressing or heating, and a method of extrusion lamination. An ordinary coating method, and if necessary, a dry lamination method using an adhesive or a hot melt adhesive can be used.

When the polyurethane resin is applied as a solution, the solvent for dissolution is usually an aromatic solvent such as benzene, toluene, or xylene, or an ester solvent such as ethyl acetate or butyl acetate: methanol, ethanol, or the like. Alcohol solvents such as isopropyl alcohol and n-butanol: ketone solvents such as acetone, methyl ethyl ketone and methyl isobutyl ketone can be used alone or in combination.

The polyurethane resin film can be obtained from a polyurethane solution, but the polyurethane resin itself obtained by the reaction between the polyester polyol and the isocyanate can be heated and melted to form a film by an extrusion method.

The thickness of the laminate layer is 1 to 100 μm,
It is preferably 5 to 30 μm, and the coating amount is 10
２００200 g / m ² , preferably 20-100 g / m ² . The laminate layer may be coated on the entire surface of the woven fabric constituting the airbag, or may be partially coated if the average air permeability seen from the entire surface of the airbag is 2 ml / cm ² / min. . By laminating the urethane resin, the tensile strength and the tear strength of the urethane resin are added to the strength of the woven fabric, so that the mechanical strength of the airbag is improved.

[0026]

EXAMPLES The present invention will now be described specifically with reference to examples, but the present invention is not limited to these examples. “%” Indicates “% by weight” unless otherwise indicated.
“Ratio” indicates “weight ratio”.

(Synthesis Example 1: Synthesis of Polyester Polyol) A 3 liter flask equipped with a condenser, a dehydrating tube, a stirrer, a thermometer and a nitrogen gas introducing tube was charged with 3,
3,5-trimethylhexanediol and 3,5,5
1,578.2 g of trimethylhexanediol (ratio 1: 2.7) and 1,194.9 g of adipic acid were charged and reacted by heating. Water began to distill at an internal temperature of around 160 ° C., and the reaction temperature was raised to 180 ° C. over about 4 hours. When the distillation of water decreases, the reaction temperature is raised to 200.
C. and continued to distill water. The acid value of the reaction solution is 5 to 10
10ppm of tetrabutyl titanate
A considerable amount was added, the internal temperature was raised to 210 ° C., and the reaction was further continued. After 6 hours, the reaction was terminated when the acid value became 0.5 or less, and a polyester polyol solution was obtained. This solution has an acid value of 0.2, a hydroxyl value of 56.4, a viscosity of 11,
900 cp / 25 ° C., APHA was 10.
The number average molecular weight of the polyester polyol is 200
It was 0.

(Synthesis Example 2: Synthesis of polyurethane resin A)
Contents 2 equipped with stirrer, thermometer, nitrogen gas inlet tube
Isophorone diisocyanate 22 in a liter flask
When 2 g was charged and the internal temperature was adjusted to 60 ° C., 1,000 g of the polyester polyol solution obtained in Synthesis Example 1 was added to 30 g.
Dropped over minutes. After completion of the dropwise addition, the reaction was carried out for 4 hours while maintaining the reaction temperature at 100 ° C., and a urethane prepolymer having a free isocyanate value of 3.2% was obtained. To this, 815 g of methyl ethyl ketone is added, and the mixture is stirred and a homogeneous solution (hereinafter referred to as “solution A”)
Called. ). Next, 78.2 g of isophoronediamine and di-n-butylamine in a 5-liter flask were added.
16 g, 1221.5 g of methyl ethyl ketone and 1,024.4 g of isopropyl alcohol were taken and stirred to make the mixture uniform. After setting the internal temperature of the reaction solution within the range of room temperature to 40 ° C. and dropping the whole amount of the solution A ′ over 30 minutes, the internal temperature was set to 50 ° C. and the reaction was performed for 3 hours. The obtained polyurethane resin solution (hereinafter, referred to as “solution A”) had a resin solid content of 30%, a viscosity of 2,440 cp / 25 ° C., and an Mn of 56,8 by GPC.
80, Mw / Mn was 1.98, and Mw was 112,780.

(Example 1) As a woven cloth, a total fineness of 5
Polyester fibers of 00 denier, 96 filaments and strength of 9.0 g / denier were used, and 39 warps / inch plain weave were used for both warp and weft. The plain woven fabric was impregnated with a thiourea compound by a conventional method and subjected to a flame retardant treatment. The solution of the polyurethane resin A obtained in Synthesis Example 2 was applied to one surface of a woven fabric such that the amount of the coating film when dried was 50 g / m ² , and then heated and dried to obtain a laminated fabric. An airbag was produced by cutting the laminated cloth so that the laminated portion was on the inside.

Example 2 In Example 1, instead of the solution of the polyurethane resin A obtained in Synthesis Example 2, 200 g of the polyurethane resin A obtained in Synthesis Example 2 and chlorinated polypropylene (manufactured by Nippon Paper Industries Co., Ltd.) SUPERCLON 813A ”, a chlorine content of 30 wt%, and a non-volatile content of 30 wt%), and a uniform and transparent composition (non-volatile content of 30 wt%).
%) Except that% was used.

(Example 3) As a woven fabric, a total fineness of 8
A 40-denier, 162 filament, strength 9.5 g / denier 6,6 nylon fiber was used, and a warp yarn and a weft yarn were 25 plain fibers / inch. Synthesis Example 2
After impregnating the woven fabric with the solution of the polyurethane resin A obtained in the above so that the coating amount upon drying was 40 g / m ² , the resultant was heated and dried to obtain a laminated fabric. An airbag was prepared by cutting the laminated cloth.

Example 4 A nylon 6 fiber having a total density of 420 deniers, 72 filaments and a strength of 9.1 g / denier was used.
Inch plain weave was used. Thiourea 5 was added to 100 parts by weight of the solution of the polyurethane resin A obtained in Synthesis Example 2.
Parts by weight, and the total amount of the coating when dried is 55 g / m
After application to both surfaces of the fabric to be ^2, the heating and then dried to obtain a laminate fabric. An airbag was produced by cutting the laminated cloth so that the laminated portion was on the inside.

The airbag obtained in each of the above embodiments is
All have good adhesion to woven fabric, light weight, excellent strength,
Flame-retardant, furthermore it does not contain a plasticizer in the coating layer, so there is no adhesion between woven fabrics even when stored for a long time at high temperature, the airbag inflates smoothly even when the inflator is activated, and the air from the inflator Pinholes are difficult to make even with small metal pieces, and air blocking performance is 2ml / c
m ² / min or less.

[0034]

According to the present invention, the inflatability of the airbag,
A thin, lightweight, lightweight, high-strength airbag that is excellent in adhesion to woven fabric, weather resistance, and pinhole resistance, does not protrude due to additives, and can be easily obtained.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI D06M 15/248 D06M 15/248 13/38

Claims (5)

[Claims] 1. A polyurethane resin comprising a polyester polyol and a diisocyanate compound having a number average molecular weight of 500 to 5,000, containing at least 50% by weight of ester units of a trimethyl-1,6-hexanediol and an aliphatic dicarboxylic acid. And a laminated fabric formed by laminating at least one surface of a synthetic resin filament fabric. 2. The laminate fabric according to claim 1, wherein the aliphatic dicarboxylic acid is adipic acid. 3. The laminated fabric according to claim 1, wherein the polyurethane resin contains a flame retardant. 4. The laminated fabric according to claim 3, wherein the flame retardant is a chlorinated polyolefin or a thiourea compound. 5. An airbag for a vehicle, comprising the laminated cloth according to claim 1.