KR20200059542A - Fabric for airbag, and method of preparing the same - Google Patents

Abstract

The present invention relates to an air bag fabric, and a method of manufacturing the same, wherein the air bag fabric comprises: a fiber base layer including aramid fibers; and an adhesive film layer, wherein the aramid fibers are coated with a fiber coating agent including a thermoplastic polyurethane resin. According to the present invention, the air bag fabric comprises: a fiber base layer of a high-density fabric in which aramid fibers are coated with a fiber coating agent; and a thermosetting polyurethane-based adhesive film layer formed on one surface or both surfaces of the fiber base layer such that a ventilation rate of the air bag fabric is significantly small, whereas uniform air permeability is maintained throughout the entire fabric, and the fabric has excellent tensile strength and elongation, thereby exhibiting superior air blocking and waterproof properties.

Description

Fabric for airbag and its manufacturing method {FABRIC FOR AIRBAG, AND METHOD OF PREPARING THE SAME}

The present invention relates to a fabric for airbags and a method for manufacturing the same, and more specifically, a fiber-based layer of a high-density fabric coated with aramid fibers with a fiber coating agent, and a thermoplastic polyurethane-based adhesive formed on one or both surfaces of the fiber base layer The airbag fabric, including the film layer, has a very small air permeability, and can maintain a constant air permeability throughout the fabric, and has excellent tensile strength and elongation, making the fabric for airbags with excellent air blocking and waterproof properties, and It relates to a manufacturing method.

Recently, in the event of a flood and an overturning accident on a marine vessel, an airbag has been developed and commercialized to secure the safety of human lives and the loss of vehicles and vessels.

In addition, in the event of flooding or flooding, flooding or flooding, the accident vehicle or human life is exposed to flooding and sinking crisis. In this situation, it is necessary to provide an airbag capable of providing buoyancy to a sunken vehicle to support an accident vehicle in order to secure a time for evacuation and in the event that a vehicle or a transportation vehicle is lost.

These airbags are protected by being expanded and expanded within a short period of time, and the airbag fabric must have a very small amount of airflow, and a certain level of strength is required to withstand the impact during airbag operation.

In addition, it is necessary to prevent and improve the burstability of the airbag sewing part in order to maintain the internal pressure of the airbag at a predetermined level or more when the airbag is expanded and deployed to lift the object.

Conventionally, as a means of reducing the air permeability of the airbag, a coating fabric having a resin applied to a fabric or adhering a film has been proposed, but in this case, it is difficult to sufficiently secure the inherent properties of the fabric, making it unsuitable for manufacturing a large capacity airbag. There was.

In addition, in order to improve the durability and waterproofness of the airbag, a coating fiber is coated with a yarn that is a material of the fabric, or a film is attached to the fabric surface to be coated, or a coating fiber and fabric coating treatment are used in combination. Methods have been proposed.

However, in order to attach the film to the coated fiber, a film laminating process is applied, and the conventional film laminating process uses a method through heat treatment and a method using an adhesive. However, the method through heat treatment has excellent work speed, but may cause deformation of the material, and there is a problem in that the bonding property is poor depending on the state of the fabric. On the other hand, when the adhesive is used, the adhesive strength is excellent, but a separate pre-treatment process such as applying the adhesive is required, and thus the efficiency of the operation decreases and the cost increases, making it difficult to perform a large amount of work.

Korean Patent Publication No. 2014-0087848

In order to solve the problems of the prior art as described above, the present invention can maintain a constant air permeability throughout the entire fabric, while at the same time the air bag fabric has a very small amount of air permeability, and has excellent tensile strength and elongation, thereby preventing and blocking air. An object of the present invention is to provide a fabric for airbags having waterproof properties and a method for manufacturing the same.

The above and other objects of the present invention can be achieved by the present invention described below.

In order to achieve the above object, the present invention comprises a fibrous base layer comprising an aramid fiber; and an adhesive film layer; wherein the aramid fiber is coated and coated with a fiber coating agent comprising a thermoplastic polyurethane resin. It provides a fabric for the airbag.

The aramid fiber is characterized in that the p- aramid fiber having a fineness of 200 to 2000 denier.

In addition, the fiber coating agent from the group consisting of butadiene rubber (BR), ethylene-propylene terpolymer rubber (EPT), ethylene-propylene rubber (EPM), ethylene-propylene diene rubber (EPDM) and styrene-butadiene rubber (SBR) It may further include at least one selected rubber component.

The fiber base layer is 15 to 50% of the total thickness of the aramid fiber is coated with the fiber coating agent.

The adhesive film layer includes a thermoplastic polyurethane or ethylene vinyl acetate material.

The adhesive film layer is characterized in that the thickness is 0.1 ~ 0.5mm.

In addition, the present invention is a method for manufacturing an airbag fabric, comprising the steps of preparing a fiber base layer by coating and coating an aramid fiber through a high temperature injection and coating a fiber coating agent comprising a thermoplastic polyurethane resin; Preparing an adhesive film layer; And heat-melting and bonding the fiber base layer and the adhesive film layer to provide a method for manufacturing an airbag fabric.

In the step of fusion bonding, the surface of the fiber base layer is heat-melted at a temperature of 130 to 150 ° C for 4 to 9 seconds.

According to the present invention, including the fiber-based layer of a high-density fabric coated with aramid fibers with a fiber coating agent; and, a thermoplastic polyurethane-based adhesive film layer formed on one or both surfaces of the fiber base layer; At the same time as being very small, it is possible to maintain a constant air permeability across the entire fabric, and has excellent tensile strength and elongation, thereby providing an airbag fabric having excellent air blocking and waterproof properties and a method of manufacturing the same.

1 is a photograph showing an airbag made of an airbag fabric according to an embodiment of the present invention.
2 is a diagram schematically showing a method of manufacturing aramid fibers coated with a fiber coating agent according to the present invention.
3 is a photograph showing a state of aramid fibers forming a fiber base layer according to an embodiment of the present invention.
Figure 4 is a photograph showing a fabric made of aramid fibers according to an embodiment of the present invention.

Hereinafter, the fabric for the airbag of the present disclosure and a method of manufacturing the same will be described in detail.

The present inventors tried to develop a fabric for an airbag having excellent air permeability and excellent tensile strength and elongation without forming a pressure-sensitive adhesive layer by applying a separate pressure-sensitive adhesive, and coated with a fiber coating agent containing a thermoplastic polyurethane resin. When forming the fibrous base layer with the aramid fibers, it was found that the air permeability was very small and the tensile strength and elongation were excellent, and based on this, the result was sold to the research, and the adhesive film layer formed using a specific type of thermoplastic resin was developed. When used, it was confirmed that the air-blocking property and the water-proofing property were improved due to the excellent adhesiveness without the need to form a separate adhesive layer, thereby completing the present invention.

The fabric for the airbag of the present invention comprises a fiber base layer comprising an aramid fiber; an over-adhesive film layer; and the aramid fiber is coated with a fiber coating agent comprising a thermoplastic polyurethane resin.

The aramid of the present invention (aramid) is one of the above-mentioned nylon-based polymer, the phenyl ring is connected to all the main chain except the amide group, showing excellent mechanical properties with a modulus of 10 times or more compared to nylon, has a high melting point of 480 ° C or higher and also has a heat capacity It is high and shows excellent heat resistance. The aramid is divided into a meta-type (m-) and a para-type (p-) containing a repeating unit represented by the following Chemical Formula 1 according to the connection state of the phenyl ring.

[Formula 1]

In the present invention, it is most preferable to use the p-aramid fibers having fineness of 200 to 2000 denier as the aramid fibers in order to achieve the desired effect of the present invention.

Specifically, it is preferable to use poly (p-phenylene terephthalate) as the aramid fiber included in the fiber base layer. In the case of the para-type (p-) aramid fiber, the phenyl ring is laminated to each other in a plate shape, so that the crystallinity is very high, the heat resistance is excellent, the fiber of the present invention due to the excellent mechanical properties of high strength, high elastic modulus with low shrinkage It is suitable as a fiber included in the base layer.

As another example, the fibers forming the fiber base layer of the present invention may be made of only aramid fibers, but may further include nylon fibers to improve folding performance.

In the case of further including nylon fibers, it is preferable to use nylon 66 fibers in terms of tensile strength and air permeability, in this case, yarns in the oblique direction use only aramid fibers, and nylon 66 fibers only for yarns in the weft direction or Alternatively, the yarn in the warp direction may use only nylon 66 fibers and the yarn in the weft direction may use only aramid fibers.

In the present invention, it is most preferable that the fiber forming the fiber base layer has a ratio of 90 to 100% of p-aramid fiber in the total fiber base layer.

In addition, the aramid fiber is preferable in that the use of aramid fibers having a fineness of 200 to 2,000 denier, or 200 to 1,000 denier can reduce the air permeability of the fabric.

Specifically, the aramid fiber is, for example, the number of filaments is 100 to 700, the elongation is 2.8 to 3.8%, the breaking strength is 2,500 to 3,200MPa, the heat shrinkage is less than 2%, specifically using 0.1 to 2% It is preferable from the standpoint of having excellent tensile strength while keeping the air permeability of the fiber base layer small.

Here, the elongation, the breaking strength and the heat shrinkage can be measured according to the measurement method used in the field to which the present invention belongs, for example, the elongation can be measured according to ASTM D 638, the breaking strength is ASTM D It can be measured according to the -638 method, and the heat shrinkage rate is allowed to leave the yarn for 24 hours in a constant-temperature and constant-humidity chamber at a standard condition, i.e., a temperature of 25 ° C and a relative humidity of 65% for 5 minutes in an oven at 100 ° C. The yarn is left again, and the yarn is left for 24 hours in a standard state. The degree of reduced length of the yarn can be measured by the shrinkage ratio according to the following equation.

Equation: Shrinkage (%) = (L0-L1) / L0 × 100

In the above equation, L0 is the length measured under superload (0.01 g / d) after the sample is left for 24 hours in the standard state, and L1 is the sample reduced under superload (0.01 g / d) after heat is applied for a certain period of time. Is the length of

The aramid fiber may have a tensile strength of 20 to 30g / d, when the tensile strength of the aramid fiber is less than 20g / d, the fabric may be torn at a great impact, and the aramid fiber has a tensile strength of 30g / d. If it exceeds, it is difficult to manufacture the fabric, and the productivity of the airbag may be reduced. Tensile strength of the substrate, for example, can be measured by the standard of ASTM D 5034.

In the present invention, the weaving form of the fiber base layer may be a weaving form generally used in the field to which the present invention belongs, and as a specific example, both a flat fabric and an OPW (One Piece Woven) type weaving shape are preferred. , The fiber base layer may be manufactured using a conventional weaving machine, and is not limited to using any specific loom, but, for example, a plain weave type fabric is a rapier loom or an air jet loom (Air Jet Loom) or a water jet loom (Water Jet Loom).

In addition, the present invention is characterized in that in order to lower the air permeability, the aramid fibers are coated and coated with a fiber coating agent comprising a thermoplastic polyurethane resin.

The thermoplastic polyurethane resin can be synthesized from polyols, low molecular weight diols and diisocyanates. Here, polyol is one of the main components of the urethane coating agent, and may be at least one selected from the group consisting of polycarbonate-based polyols, polyether-based polyols, polyester-based polyols, and silicone-based polyols. .

Further, the diisocyanate may be one or more selected from the group consisting of isophorone diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, and hexanediol diisocyanate.

In addition, the low-molecular diol is a diol compound having 2 to 20 carbon atoms, for example, ethylene glycol, propylene glycol, diethylene glycol, triethylene glycol, 1,2-butylene glycol, 1,3-butylene glycol, 2,3 -Butylene glycol, 1,4-butylene glycol, 1,5-pentanediol, neopentyl glycol, 1,6-hexane glycol, 2,5-hexanediol, dipropylene glycol, 2,2,4-trimethyl- And 1,3-pentanediol, 1,4-cyclohexanedimethanol, 2,2-dimethylpropanediol, and 1,4-butanediol.

The thermoplastic polyurethane resin, for example, may have a Shore A hardness of 60 to 80, 70 to 80, and within this range, there is an effect of excellent adhesion to the aramid fiber. The Shore A hardness may be measured according to JIS K-7311 as an example.

In addition, the thermoplastic polyurethane resin may have a density of 0.5 to 1.5, or 1.0 to 1.4 to realize a lightweight airbag fabric. This density can be measured according to ASTM D 792.

More specifically, the thermoplastic polyurethane resin has a tensile strength of 250 kg / cm 2 or more, or 250 to 500 kg / cm 2, measured according to ASTM D412, and an elongation of 500% or more measured according to ASTM D 412, or It is preferable from the viewpoint of durability of the airbag to use 500 to 900%, and a mold shrinkage measured according to ASTM D 955 of 30 to 60 m / m, or 40 to 55 m / m.

In addition, the fiber coating agent from the group consisting of butadiene rubber (BR), ethylene-propylene terpolymer rubber (EPT), ethylene-propylene rubber (EPM), ethylene-propylene diene rubber (EPDM) and styrene-butadiene rubber (SBR) It may further include at least one selected rubber component.

Here, when the ethylene-propylene diene rubber (EPDM) is included in the fiber coating agent, the ethylene content is 50 to 90% by weight, or 80 to 90% by weight, and the pattern viscosity (ML1 + 4 @ It is preferable to use EPDM having a temperature of 50 to 60 ° C in terms of adhesion to aramid fibers and durability of the airbag. The pattern viscosity of the substrate can be measured by using a ASTM D1646 pattern viscometer, a torque value measured 4 minutes after preheating at 100 ° C for 1 minute using a large rotor.

In addition, when the butadiene rubber (BR) is included in the fiber coating agent, the content of cis-1,4 butadiene measured in accordance with ASTM D1416 is 90 to 99% by weight with respect to the entire butadiene rubber and the pattern viscosity is 50 to 60, The use of butadiene rubber having a specific gravity of 0.15 to 1.21 has an effect of excellent abrasion resistance and water resistance of the airbag.

The fiber coating agent according to the present invention includes a thermoplastic polyurethane resin, or a weight ratio of a rubber component to a thermoplastic polyurethane resin (TPU) (TPU: rubber component) 70 to 95: 30 to 5, or 80 to 90: 20 to 10 It can be used in combination.

In another example, the fiber coating agent of the present invention, with respect to the total 100% by weight of the fiber coating agent, 5 to 15% by weight of a plasticizer, 0.01 to 1% by weight of an antioxidant, 1 to 10% by weight of a coupling agent, 0.1 to 0.1% of a fatty acid ester 2% by weight; It may further include 5 to 15% by weight of a thickener in which one or more of silica and calcium carbonate are mixed.

In addition, depending on the situation, the fiber coating agent further includes at least one additive selected from inorganic fillers, stabilizers, lubricants, antifreeze agents, ultraviolet absorbers, antistatic agents, antiseptics and antibacterial agents, and is coated on the aramid fiber surface to form a coating. At the same time, it is possible to further improve antibacterial and waterproof properties.

As described above, the fiber coating agent according to the present invention is composed of a composition further comprising a rubber component on the basis of a thermoplastic polyurethane resin, so that the fiber coating agent itself has high adhesion to amaride fibers, high abrasion resistance and high friction fastness. Since no cracking occurs and the fiber coating agent components do not aggregate with each other when mixed, the coating property is excellent and a uniform coating layer can be formed.

The method of coating and coating the aramid fiber with a fiber coating agent containing a thermoplastic polyurethane resin is introduced into the hopper using a fiber coating agent prepared in a master batch form using an injection machine, as shown in FIG. 2 below, and the aramid fiber in the master batch. By mixing and forming and injecting a fiber material composition, aramid fibers coated and coated with a fiber coating agent may be prepared.

The fiber base layer may be coated with the fiber coating agent 15 to 50% of the total aramid fiber thickness.

Specifically, it is preferable that the fiber coating agent is coated so that the thickness of the aramid fiber coated with the fiber coating agent is 15 to 50%. If the coating content is less than 15%, the fiber yarn is poor due to poor focusing power, and when it exceeds 50%, it is difficult to manufacture the fabric due to excessive thickness and weight of the coated fiber, and the weight of the produced fabric Increases greatly and the efficiency of use decreases.

The adhesive film layer of the present invention includes a thermoplastic polyurethane or ethylene vinyl acetate material.

The present invention by applying a thermoplastic polyurethane or ethylene vinyl acetate material as an adhesive film. It is easily deformed by heat, so that it is possible to have excellent adhesion during the attachment operation through heat treatment.

The adhesive film layer is coated with a coating amount per unit area of 150 to 250 g / m 2, and preferably has a thickness of 0.12 to 0.30 mm.

If the thickness of the adhesive film layer is less than 0.12 mm, the thickness of the adhesive film layer is thinner than the coating layer on the fabric surface, so that the film for bonding can be melted and absorbed by the heat of the film layer, and the film thickness is thin even if it is bonded to the fabric without being absorbed. It is difficult to ensure sufficient waterproofness and durability of the finished fabric. On the other hand, when the thickness of the bonding film exceeds 0.30 mm, there is a problem in that the excessive weight and thickness of the bonding film layer decreases the flexibility of the fabric and the bonding strength with the coating layer formed on the fabric surface.

In the case of the warp density and the weft density of the airbag fabric of the present invention, the warp density may be 40 to 50 th / inch, more preferably 46 to 49 th / inch. The weft direction density may be 40 to 50 th / inch, more preferably 46 to 49 th / inch, and in this case, the airtightness of the fabric may be improved and folding property may be improved.

The fabric for the airbag of the present invention is laminated with the adhesive film layer containing a specific thermoplastic resin as described above on the surface of the fiber base layer, so that the adhesive can be adhered to the fiber base layer without treating a primer coating that reinforces special adhesion. The film layer can be easily attached to provide excellent adhesion, air permeability near zero, and provide durability for improved airbag fabric.

The fabric for the airbag may have a tensile strength property of 400 N / 5cm or more or 400 to 3,000 N / 5cm of the fabric measured by the method of International Standardization Organization Standard ISO 13937-1. Thus, the fabric for the airbag of the present invention can obtain sufficient rigidity and durability effects as an airbag.

In addition, the fabric for the airbag may have a tear strength property of the fabric measured by the method of International Standardization Organization Standard ISO 13937-1 of 35 N / mm or more or 35 to 100 N / mm. This may have an effect of preventing the fabric from being torn by high temperature / high pressure gas when the airbag cushion is deployed.

In addition, the fabric for the airbag may have a tensile strength of 260 N / mm or more, or 260 to 500 N / mm after a weatherability test measured by the methods of ISO-4892-1 and ISO-4892-2, of ISO 13934-1 The tensile elongation measured by the method can satisfy 60% or more.

In addition, the present invention is a method for manufacturing an airbag fabric, comprising the steps of preparing a fiber base layer by coating and coating an aramid fiber through a high temperature injection and coating a fiber coating agent comprising a thermoplastic polyurethane resin; Preparing an adhesive film layer; And heat-melting and bonding the fiber base layer and the adhesive film layer to provide a method for manufacturing an airbag fabric.

The coating of the fiber coating agent is made through high temperature injection of 160 to 240 ° C, and after injection, it is cooled through a water-cooled cooling device and then completely dried through a hot air dryer. The temperature at the time of injection in the injection machine does not exceed 240 ° C, and if it exceeds this temperature, a problem occurs in that the fiber coating agent is decomposed. On the other hand, when the temperature of the injection machine is less than 160 ° C, the fiber coating agent is not sufficiently heated to melt and does not easily adhere to the yarn.

In addition, when the coated fiber is prepared, a water-soluble oil may be applied to the coated fiber. The coated fiber has a self-adhesiveness as a thickener included in the fiber coating, and the viscosity and friction are high, so that the weaving orthogonal to the warp during weaving is non-uniform, leading to difficulties in fabric manufacturing. Accordingly, a water-soluble oil may be applied to increase the lubricating property on the surface of the coated fiber, thereby improving weavability. The water-soluble oil used at this time is not particularly limited, and for example, water-soluble oil for canning can be used.

Fabrics as shown in FIG. 4 may be manufactured by using the weaving machine using the coated fibers as warp and weft yarns. The fabric manufactured in such a condition that lubricity at the time of supplying the coated fiber is smooth may have a uniform shape as shown in FIG. 4.

Thereafter, when the woven fabric is manufactured by using the coated fiber as warp and weft, a bonding film to be attached to the fabric is prepared, and a bonding film is attached to the fiber base layer to complete the airbag fabric. At this time, the heat-sealing of the fabric proceeds for 4 to 9 seconds at a temperature of 130 to 150 ° C, and in this process, a film layer of 0.10 to 0.20 mm thickness is formed on the fabric surface. However, the film layer formed on the surface of the fabric is a melted fiber coating agent again cured in the process of manufacturing the coated fiber, and the thickener included in the fiber coating agent is also melted in the process of forming the film layer so that the film layer has viscosity. A film for bonding is attached to the fabric surface by using the viscosity of the film layer. Then, the fabric to which the bonding film is attached is compressed and cooled with a continuous cooling press so that the film is completely attached to the fabric.

Hereinafter, a preferred embodiment is provided to help the understanding of the present invention, but the following examples are only illustrative of the present invention, and it is apparent to those skilled in the art that various changes and modifications are possible within the scope and technical scope of the present invention. It is natural that such modifications and corrections fall within the scope of the appended claims.

 [Example]

Manufacturing example

(1) Manufacture of master batch for extrusion coating

Thermoplastic polyurethane resin 60 to 80 wt%, plasticizer 5 to 15 wt%, antioxidant 0.01 to 1 wt%, coupling agent 1 to 10 wt%, fatty acid ester 0.1 to 2 wt%, silica, calcium carbonate 5 to 15% by weight of one or more of the thickeners mixed with a kneader mixer (kneader mixer) at a chamber temperature of 160 ° C, a rotor of 20 rpm, and a mixing time of 12 minutes were mixed, and hydraulic press at 160 ° C for 5 minutes. A masterbatch was prepared using.

(2) Aramid fiber extrusion coating coating and drying

The prepared yarn and the masterbatch are put into an extruder to coat the core with aramid and the sheath with a thermoplastic urethane resin to prepare coated fibers. At this time, the melting temperature of the injection machine is adjusted to 180 to 200 ° C, and after injection, it is rapidly cooled through a water-cooled cooling device at room temperature. After cooling, the product is completely dried through a hot air dryer, and dried at 1000 rpm through a winder to prepare a finished fiber yarn.

The extrusion process conditions were carried out as follows,

[Ester Type TPU (for extrusion molding) Resin's temperature condition table for each coating part]

Extrusion condition /
Extrusion Condition Condition 1 Condition 2 Zone 1 ℃ 195 195 Zone 2 210 205 Zone 3 210 210 Zone 4 220 220 Adapter Dies 170 190 Extrusion speed 214 RPM 172 RPM Current meta 2.4 Amp 1.7 Amp

(3) Technical considerations on the properties of extrusion direct coating

The most basic property of polymers is that molecular weights are 100 to 10000 times larger than ordinary molecules. When the molecular weight is increased, physical properties such as impact strength, tear strength, stress resistance, and elongation have been improved, and the MI value is an index of molecular weight and refers to the amount of resin flowing for 10 g depending on temperature and weight. When MI increases, physical properties such as tensile strength, elongation, tear strength, and impact strength degrade as shown in the figure below. In the present invention, by using a master batch for extrusion coating, by directly extruding with aramid fibers and coating coating, it solved the problem that the physical properties are lowered.

(4) Preparation of fiber base layer

The coated fiber is applied with a water-soluble oil before the fabric manufacturing process. Because of the non-slip property of the coated fiber, a non-uniformity of the weft supply orthogonal to the warp can cause a non-uniformity of the fabric, so that a water-soluble oil can be applied to increase the weavability. When water-soluble oil is applied, the fabric is made of coated fibers.

At this time, the fabric was produced using a picanol loom, and the production speed was 300 rpm / min.

Thereafter, by adjusting the temperature to be in a straight line in the hot air dryer, the drying temperature was set at 120 ° C in the initial chamber 1, 150 ° C in the chambers 2 to 4, and 100 ° C in the chambers 5 to 6, and the width of the fabric was fixed to complete the fabric. After passing through the cooling roller to achieve the final product. At this time, the production speed was 25 m / min, and the over feed tension was uniformly processed in the warp and weft directions to form a right angle as shown in FIG.

(5) Preparation of adhesive film

When the fabric manufacturing is completed, an adhesive film to be attached to the fabric is prepared. A thermoplastic polyurethane film is used as the adhesive film, and is easily deformed by heat, and is suitable for adhesion through heat treatment. The thickness of the adhesive film is preferably 0.10 to 0.20 mm.

If the thickness of the adhesive film is less than 0.1 mm, the thickness of the film is thin, so the fabric does not have sufficient waterproofness and durability. On the other hand, when the thickness of the adhesive film exceeds 0.2 mm, the adhesive strength is reduced due to the weight and thickness of the adhesive film.

(6) Heat fusion and film bonding

The bonding film is a T-die multi-layer co-extrusion to heat melt to form a thin coating layer on the surface of the fabric.

When the coating layer is sufficiently formed on the surface of the fabric, an adhesive film is bonded to the coating layer, and the adhesive film is completely attached to the fabric through a continuous cold press operation. At this time, by forming coating layers on both surfaces of the fabric, the adhesive film may be bonded to the coating layers on both surfaces of the fabric.

In order to confirm the functionality of the fabric after this process, the optimal working conditions were considered through Tables 2 and 3.

unit Condition 1 Condition 2 Condition 3 Condition 4 Thermal efficiency ℃ 115 125 135 145 press time sec 15 10 8 5 Heat fusion adhesion efficiency = air density test, microscope visual test

Condition 1 Condition 2 Condition 3 Condition 4 State of coating layer ○ ☆ ☆ Bonding state ○ ○ ☆ : Best, ☆: Excellent, ○: Normal, △: Poor

As shown in Table 2 and Table 3, it can be seen that the heat-melting fusion efficiency is very excellent in the range of 145 ° C and 5 to 8 seconds, and the quality is also improved.

Examples 1-3

In the fiber extrusion coating masterbatch of the preparation example, instead of 60 to 80% by weight of a thermoplastic polyurethane resin, a masterbatch containing a fiber coating agent containing a thermoplastic polyurethane resin, EPDM rubber, BR rubber as shown in Table 4 is prepared. Thus, the fabric for the airbag was prepared by the method according to Preparation Example Condition 4.

division combination Example 1 Thermoplastic polyurethane resin Example 2 Thermoplastic polyurethane resin and EPDM rubber were blended in a weight ratio of 90:10 Example 3 Thermoplastic polyurethane resin and BR rubber were blended in a weight ratio of 80:20

-Thermoplastic Polyurethane Resin: The brand name Neothane 5075A supplied by Dongsung Hichem Co., Ltd. was used for diisocyanate mixed with one or more of polyol or low molecular diol having a Shore A hardness of 77 and a specific gravity of 1.18. -EPDM rubber: Ethylene content The product name 570P purchased from Kumho Petrochemical Co., Ltd., having a weight of 70 wt%, a pattern viscosity of ML1 + 4 (125 ° C) 53, and a specific gravity of 0.87 was used.

-BR rubber: cis-1,4 content of 96 wt%, pattern viscosity ML1 + 4 (100 ℃) 55, specific gravity 0.9 was purchased from Kumho Petrochemical Co., Ltd. brand name was used.

Comparative Example 1

In Example 1, except for not including the adhesive film layer was carried out in the same manner as in Example 1 to prepare an airbag fabric.

[Test Example]

The properties of the fabric for airbags prepared in the above Examples and Comparative Examples were measured by the following method, and the results are shown in Table 5 below.

How to measure

-Water pressure resistance (mm H ₂ 0): Water pressure resistance was measured using a water resistance tester (model name FX 3000).

-Air permeability (cfm): Air permeability was measured using an air permeability tester (model name: M021A).

-Tensile strength (N): According to the KS K0521 Strip method, the specimen size was measured under the specimen size 25 mm X 150 mm and speed: 300 mm / min.

-Tear strength (N): measured according to KS K ISO 13937-1 (Pan Dulum Method).

-Wear resistance (times): measured according to ASTM D 3884 (Daver method).

-Waterproof (mmH ₂ O): was measured based on KSKISO811 (AATCC127).

division Example 1 Example 2 Example 3 Comparative Example 1 Water pressure resistance (mmH ₂ 0) 13,000 > 10,000 > 10,000 10,000 Air permeability (cfm) 0.007 0.000 0.000 0.015

As shown in Table 5, Examples 1 to 3 according to the present invention can be confirmed that the water pressure is all 10,000 mm H ₂ 0 or more, air permeability of 0.007 cfm or 0.000 cfm can maintain the airtightness close to zero. there was.

Reference example

After dyeing the fabric for the airbag in Example 1 as shown in Table 6 below, tensile strength, tear strength, abrasion resistance and water resistance were measured.

division Measurement result Tensile strength (N) # 1 (Orange) slope 1982 Weft 872 # 2 (Y / Green) slope 1449 Weft 1194 # 3 (Green) slope 1972 Weft 1390 # 4 (Blue) slope 1657 Weft 1066 Tear strength (N) # 1 (Orange) slope 91.1 Weft 86.6 # 2 (Y / Green) slope 51.6 Weft 68.1 # 3 (Green) slope 98.9 Weft 71.4 # 4 (Blue) slope 56.6 Weft 45.2 Abrasion resistance (times) # 1 (Orange) More than 2000 # 2 (Y / Green) More than 2000 # 3 (Green) More than 2000 # 4 (Blue) More than 2000 Waterproof
(mmH ₂ O)

# 1 (Orange) Over 20,000 # 2 (Y / Green) Over 20,000 # 3 (Green) Over 20,000 # 4 (Blue) Over 20,000

As shown in Table 5, even if the color of the fabric for the airbag is dyed differently, the tensile strength and tear strength of the warp and weft in all colors are excellent, but the wear resistance is more than 20,000 times, and the water resistance is 20,000 mmH ₂ O or more. It was confirmed that it was excellent.

Claims (8)

Fiber base layer comprising aramid fibers; And
Adhesive film layer; containing,
The aramid fiber is an airbag fabric, characterized in that coated with a fiber coating agent containing a thermoplastic polyurethane resin.
According to claim 1,
The aramid fiber is an airbag fabric characterized in that the p- aramid fiber having a fineness of 200 to 2000 denier.
According to claim 1,
The fiber coating agent is selected from the group consisting of butadiene rubber (BR), ethylene-propylene terpolymer rubber (EPT), ethylene-propylene rubber (EPM), ethylene-propylene diene rubber (EPDM) and styrene-butadiene rubber (SBR). Airbag fabric characterized in that it further comprises a rubber component of the species.
According to claim 1,
The fiber base layer is an airbag fabric characterized in that 15 to 50% of the total aramid fiber thickness is coated with the fiber coating agent.
According to claim 1,
The adhesive film layer is an airbag fabric, characterized in that it comprises a thermoplastic polyurethane or ethylene vinyl acetate material.
According to claim 1,
The adhesive film layer is an airbag fabric, characterized in that the thickness is 0.1 ~ 0.5mm.
In the manufacturing method of the airbag fabric,
Preparing a fiber base layer by coating and coating aramid fibers with a fiber coating agent comprising a thermoplastic polyurethane resin through high temperature injection;
Preparing an adhesive film layer; And
A method of manufacturing a fabric for an airbag, comprising; thermally melting and bonding the fiber base layer and the adhesive film layer to fusion bonding.
The method of claim 7,
In the step of fusion bonding, the method of manufacturing a textile for a transport container is characterized in that the surface of the fiber base layer is heat-melted at a temperature of 130 to 150 ° C for 4 to 9 seconds.

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