JP2009179150A - Airbag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an airbag that is excellent both in housing performance and strength, and in gas tightness at junctions with favorable productivity. <P>SOLUTION: The airbag comprises two panels joined with each other by means of an adhesive seal material. The adhesive seal material is of a self-heat generating type. Preferably, a heat generation temperature of the adhesive seal material is 100°C or lower. In addition, preferably, the adhesive seal materials are sewn with each other at or in vicinities of the junctions. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an airbag that is mounted on a vehicle or the like and protects an occupant from an impact such as a collision or rollover. More specifically, the present invention relates to an airbag in which two panels are joined, and is superior in lightness, storage, strength of joints, and airtightness.

  It has been a long time since a vehicle seat airbag, a passenger seat airbag, a passenger seat airbag, and a rear seat airbag have been installed as vehicle airbags. In recent years, the use of side airbags and curtain shield airbags corresponding to side collisions has increased. Among these, curtain shield airbags corresponding to vehicle rollovers have attracted attention, which includes a long period of several seconds during which the vehicle rolls over in order to absorb the impact on the occupant's head. It is required to maintain the internal pressure over the entire area. In order to cope with airbags of these various forms and required performance, it is urgent to develop an airbag capable of increasing the airtightness of the airbag and extending the inflating duration more than before.

  As such an airbag, Patent Document 1 discloses that gas leakage from a joint portion is made by joining edges of two panels made of woven fabric or the like by bonding with an elastic adhesive and stitching with a thread. An airbag that prevents the above is disclosed.

  Patent Document 2 discloses a high-frequency welding type adhesive and Patent Document 3 discloses a heat-sealable polymer as an adhesive used for the joint, but a special device is required for bonding. Further, since the adhesive is deformed by moving to the curing step, there is a problem that the effect of suppressing gas leakage is lowered and it is difficult to satisfy the performance as an airbag.

  Patent Document 4 discloses a chemically reactive adhesive, and the curing condition is 150 ° C. for 10 minutes or room temperature for 3 days.

  As shown in Patent Document 4, heating is generally performed in order to accelerate the curing time of the addition reaction type adhesive sealing material. The higher the heating temperature, the longer the curing time. Can be fast.

  As a method of heating, there is a method of using a dryer or the like to warm the air and placing a material coated with an adhesive sealing material in the atmosphere, or a method of placing a material coated with an adhesive sealing material on a heated plate . However, in any case, since portions other than the adhesive seal material are also heated, extra energy is applied, which is uneconomical. Further, even when only the adhesive seal material portion is heated, it is necessary to cope with various application shapes of the adhesive seal material each time, which is not efficient.

  Furthermore, since the panel which comprises an airbag normally consists of a fiber fabric, it wrinkles by heating. When the inventor conducted an experiment, the adhesive sealing material was applied to the fabric, and after heating, the temperature of the adhesive sealing material exceeded 100 ° C. The shape changed with the wrinkles of the fabric. Also, the adhesive sealing material itself generated air bubbles from around 100 ° C., and there was a concern about adverse effects on adhesiveness.

  Moreover, if it is cured at room temperature without heating, it takes a long time to complete the curing. During standing for a long time, changes in temperature and humidity cause the fabric to expand and contract, resulting in wrinkles. During this time, the adhesive seal material that is not completely cured is stretched or crushed following the generated wrinkles, and its shape changes from that at the time of application.

  Since the adhesive sealant is applied so that dimensions necessary for design can be maintained, the dimensions necessary for design cannot be maintained due to a change in shape. Furthermore, since the bubbles of the adhesive seal material reduce the area of adhesion to the fabric, the adhesive strength is insufficient and the airtightness of the airbag is reduced.

JP 2001-1854 A Japanese Patent Laid-Open No. 9-119066 JP-A-6-227346 JP-A-6-16099

  This invention is made | formed in view of such a present condition, and it aims at providing the airbag excellent in all of storage property, the intensity | strength of a junction part, and airtightness with sufficient productivity.

  As a result of intensive research to solve the above-mentioned problems, the present inventor has made the adhesive seal material itself heat-generating to quickly heat-cure, not to mention storage performance, joint strength and airtightness, and productivity. Has been found to be improved, and the present invention has been completed based on this finding.

  That is, the present invention relates to an airbag formed by joining two panels with an adhesive seal material, and the adhesive seal material is a self-heating type.

  The exothermic temperature of the adhesive sealing material is preferably 100 ° C. or lower.

  It is preferable that the adhesive sealing material contains a heat generating agent and a moisture retention agent.

  Furthermore, it is preferable to be stitched at the joint or in the vicinity of the joint.

  According to the present invention, since the adhesive sealing material itself generates heat, the sealing material can be applied and cured simultaneously, and the process can be simplified. In addition, the room temperature curing type sealing material of condensation reaction takes time to cure, so wrinkles of the base fabric are generated during the curing, and the sealing material is crushed and peeled by the wrinkles, maintaining the internal pressure (strength and airtightness of the joint) However, according to the present invention, since the curing is accelerated by heat and there is no inter-process transfer from application to heat curing, the occurrence of crushing of the sealing material can be reduced. An airbag excellent in internal pressure retention performance can be provided with high productivity.

  The airbag of the present invention is formed by joining two panels with a self-heating adhesive seal material.

  The adhesive sealing material used in the present invention preferably contains a heat generating agent in the main agent exemplified below. An exothermic agent is one that easily reacts with oxygen, water, or both in the air and generates heat of reaction due to a chemical reaction with them, or reacts by a chemical reaction that occurs when two or more substances are mixed. Any device that generates heat may be used. Although not particularly limited, for example, oxidizable accelerators such as iron, reduced iron and nickel, sodium chloride, calcium chloride, magnesium chloride, activated carbon, carbon powder, copper compound, manganese and the like can be mentioned. These may be used alone or in admixture of two or more. Of these, reduced iron is preferred because it easily generates heat of reaction.

  In the case where a material that reacts with water to generate reaction heat is used as the exothermic agent, the adhesive sealant preferably contains a moisture retention agent. Although it does not restrict | limit especially as a moisture retention agent, Wood powder, pulp powder, super absorbent polymer, etc. are mention | raise | lifted. Among these, a highly water-absorbent resin is preferable because the particle size can be easily adjusted. A highly water-absorbent resin is a cross-linked product of a hydrophilic linear or branched polymer. It is a porous material having a three-dimensional network structure of angstrom units, and it will dissolve in water when it comes into contact with water. Although it absorbs water with the force to be absorbed, it is suppressed because there is a cross-linked structure between the molecules, and due to its balance, it is a resin that becomes a hydrogel in a swollen state after absorbing a certain amount of water. For example, starch-acrylic acid graft system, polyacrylate system, polyvinyl alcohol system, vinyl acetate-acrylate system, isobutylene-maleic acid system, poly N-vinylacetamide system and the like can be mentioned. Of these, polyacrylates are preferred in terms of cost.

  In addition, the said adhesive sealing material needs to be a 2 component type which isolate | separates and prepares the material which raise | generates an exothermic reaction so that exothermic reaction may be started by mixing two components.

  The exothermic temperature of the adhesive sealing material is preferably 100 ° C. or lower. It is preferable that the exothermic temperature is 100 ° C. or lower because a change in the shape of the adhesive seal material due to wrinkles in the fabric portion to which the adhesive seal material is applied and the generation of bubbles in the adhesive seal material can be suppressed. Accordingly, it is possible to promote the curing of the adhesive seal material without requiring a heating device or a heating process while ensuring the strength and air tightness of the panel joint portion, which is very economical and efficient. The exothermic temperature is more preferably 80 ° C. or lower. Moreover, it is preferable that a minimum is 40 degreeC. When the exothermic temperature is lower than 40 ° C., the curing acceleration effect of the adhesive sealant tends to be insufficient.

  Furthermore, since the airbag obtained by joining with this adhesive sealing material has high airtightness, it is possible to hold the internal pressure for a long time, and particularly, it is necessary to hold the internal pressure for a long time. It is useful as a side airbag.

  The exothermic agent may be added to the adhesive sealing material so that the exothermic temperature is 100 ° C. or less, and is not particularly limited. Especially, it is preferable that it is 3-30 weight% with respect to an adhesive sealing material, It is more preferable that it is 5-30 weight%, It is especially preferable that it is 5-10 weight%. When the amount of the heat generating agent is less than 3% by weight, the amount of heat generation is insufficient, and the effect of promoting the curing tends to be insufficient. When the amount exceeds 30% by weight, the heat generation temperature tends to exceed 100 ° C. Here, the exothermic agent is substance A when it generates heat due to the reaction between substance A and water (or oxygen), and it is the smaller substance when it generates heat due to reaction between substance A and substance B. Say.

  Examples of the main component of the adhesive sealing material include halogen-containing rubbers such as chloroprene rubber, high baron rubber, and fluorine rubber, silicone rubber, ethylene propylene rubber, ethylene propylene terpolymer rubber, nitrile butadiene rubber, styrene butadiene rubber, and isobutylene isoprene rubber. , Rubbers such as urethane rubber and acrylic rubber, and halogen-containing resins such as vinyl chloride resin, vinylidene chloride resin, chlorinated polyolefin resin and fluorine resin, urethane resin, acrylic resin, ester resin, amide resin, olefin resin and silicone Resins such as resins are listed, and these are used alone or in combination. Of these, silicone rubber and silicone resin are preferable in terms of excellent flexibility, heat resistance, and weather resistance.

  Specific examples of the silicone rubber include those based on an organopolysiloxane having an average of two or more alkenyl groups in one molecule. Examples of the alkenyl group include a vinyl group, an allyl group, a butenyl group, a pentenyl group, a hexenyl group, and a heptenyl group. Of these, a vinyl group is preferable. Examples of the organic group bonded to the silicon atom other than the alkenyl group include alkyl groups such as methyl group, ethyl group, propyl group, butyl group, pentyl group, and hexyl group; aryl groups such as phenyl group, tolyl group, and xylyl group And halogenated alkyl groups such as 3-chloropropyl group and 3,3,3-trifluoropropyl group. Of these, a methyl group is preferable. Examples of the molecular structure of the organopolysiloxane include a straight chain, a partially branched straight chain, a branched chain, a network, and a dendritic structure.

Examples of such organopolysiloxanes include dimethylpolysiloxane blocked with dimethylvinylsiloxy group at both ends of the molecular chain, dimethylsiloxane / methylvinylsiloxane copolymer blocked with dimethylvinylsiloxy group at both ends of the molecular chain, and trimethylsiloxy group at both ends of the molecular chain. Blocked dimethylsiloxane / methylvinylsiloxane copolymer, siloxane unit represented by the formula: (CH ₃ ) ₃ SiO _1/2 and siloxane unit represented by the formula: (CH ₃ ) ₂ (CH ₂ ═CH) SiO _1/2 And an organopolysiloxane composed of a siloxane unit represented by SiO _4/2 , a part or all of the methyl groups of these organopolysiloxanes are alkyl groups such as ethyl group and propyl group; aryl such as phenyl group and tolyl group Group; 3,3,3-trifluoropropyl group Organopolysiloxanes substituted with halogenated alkyl groups such as, organopolysiloxanes in which some or all of the vinyl groups of these organopolysiloxanes are substituted with alkenyl groups such as allyl groups, propenyl groups, and the like. Two or more types of mixtures can be mentioned.

  The adhesive seal material used in the present invention contains various additives such as a curing agent, a catalyst, a filler, a curing inhibitor, an organopolysiloxane resin, a pigment, and a heat resistance agent in addition to the main agent and the heat generating agent. Also good.

  As the curing agent, an organohydrogenpolysiloxane having an average of 2 or more silicon-bonded hydrogen atoms in one molecule is used. Examples of the organic group bonded to the silicon atom include alkyl groups such as a methyl group, an ethyl group, a propyl group, a butyl group, a pentyl group, and a hexyl group; an aryl group such as a phenyl group, a tolyl group, and a xylyl group; Examples thereof include halogenated alkyl groups such as chloropropyl group and 3,3,3-trifluoropropyl group. Of these, a methyl group is preferable.

  Examples of the molecular structure of the organohydrogenpolysiloxane include linear, partially branched, branched, network, and dendritic.

Examples of such organohydrogenpolysiloxane include, for example, molecular chain both ends trimethylsiloxy group-blocked methylhydrogenpolysiloxane, molecular chain both ends dimethylhydrogensiloxy group-blocked dimethylpolysiloxane, molecular chain both ends trimethylsiloxy group-blocked dimethyl. Siloxane / methylhydrogensiloxane copolymer, dimethylphenylsiloxy group-capped methylphenylsiloxane / methylhydrogensiloxane copolymer, cyclic methylhydrogenpolysiloxane, dimethylhydrogensiloxane unit and formula: SiO _4/2 Organohydrogenpolysiloxanes composed of siloxane units represented by the following: some or all of the methyl groups of these organohydrogenpolysiloxanes are ethyl, propyl An alkyl group such as a phenyl group; an aryl group such as a phenyl group and a tolyl group; an organohydrogenpolysiloxane substituted with a halogenated alkyl group such as a 3,3,3-trifluoropropyl group, and the organohydrogenpolysiloxane Two or more types of mixtures can be mentioned. In particular, since the physical properties of the resulting cured product, in particular, elongation, are improved, organohydrogenpolysiloxane having silicon atom-bonded hydrogen atoms only at both ends of the molecular chain and silicon atom bonds in the molecular chain side chain. A mixture of organohydrogenpolysiloxanes is preferred.

  The content of the curing agent is preferably such an amount that the molar ratio of silicon-bonded hydrogen atoms to alkenyl groups in the main component is 0.01 to 20, preferably 0.1 to 10. Is more preferable, and it is further more preferable that it is the quantity used as 0.1-5. When the content is less than this, the resulting silicone rubber composition tends not to be cured sufficiently. Moreover, when there is much content, it exists in the tendency for the physical characteristic of the silicone rubber obtained by hardening to fall.

  In the case of using a mixture of an organohydrogenpolysiloxane having silicon atom-bonded hydrogen atoms only at both ends of the molecular chain and an organohydrogenpolysiloxane having silicon atom bonds in the side chain of the molecular chain as the curing agent, the former The content of the organohydrogenpolysiloxane is preferably such that the molar ratio of silicon atom-bonded hydrogen atoms to alkenyl groups in the main component is 0.01 to 10, preferably 0.1 to 10. More preferably, it is more preferably an amount of 0.1-5. The content of the latter organohydrogenpolysiloxane is preferably an amount such that the molar ratio of silicon-bonded hydrogen atoms to alkenyl groups in the main component is 0.5 to 20, preferably 0.5 to 10. It is more preferable that the amount is 0.5 to 5.

  The catalyst comprises an organopolysiloxane having an average of 2 or more alkenyl groups in one molecule as a main component, and an organohydrogen having an average of 2 or more silicon-bonded hydrogen atoms in one molecule as a curing agent component. This is for accelerating the curing reaction with polysiloxane. Examples of the catalyst include platinum fine powder, platinum black, chloroplatinic acid, platinum tetrachloride, chloroplatinic acid alcohol solution, platinum olefin complex, platinum alkenyl siloxane complex, platinum carbonyl complex, and platinum-based catalysts. Examples thereof include fine powders dispersed in a thermoplastic organic resin such as methyl methacrylate resin, polycarbonate resin, polystyrene resin, and silicone resin.

  The content of the catalyst is not particularly limited as long as it is sufficient to promote curing of the main component and the curing agent component. Especially, it is preferable that it is the quantity from which the platinum atom in a catalyst component becomes 0.01-500 weight part with respect to 1 million weight part of main ingredient components, and it is the quantity used as 0.1-100 weight part more. preferable. If the content is small, the curing reaction tends not to proceed sufficiently. If the content is too large, the raw material costs tend to be expensive, which is uneconomical.

  Examples of the filler include calcium carbonate powder, silica powder, and quartz powder.

  When the adhesive sealing material contains calcium carbonate powder, it is possible to improve the adhesion to the air-impermeable treatment agent that covers the base fabric.

BET specific surface area of the calcium carbonate powder is preferably from 5 to 50 m ² / g, and more preferably 10 to 50 m ² / g. When the BET specific surface area is smaller than 5 m ² / g, the effect of improving the adhesion tends to be insufficiently exhibited. When the BET specific surface area exceeds 50 m ² / g, the impurities contained in the calcium carbonate increase, and the physical characteristics of the cured adhesive seal material tend to deteriorate.

  Examples of the calcium carbonate powder used for such purposes include heavy (or dry pulverized) calcium carbonate powder, light (or precipitated) calcium carbonate powder, and these calcium carbonate powders as organic acids such as fatty acids and resin acids. The surface-treated powder can be raised. Among these, light (or precipitated) calcium carbonate powder is preferable, and light (or precipitated) calcium carbonate powder surface-treated with an organic acid such as fatty acid or resin acid is more preferable.

  The content of the calcium carbonate powder in the adhesive sealing material is preferably 5 to 200 parts by weight and more preferably 10 to 100 parts by weight with respect to 100 parts by weight of the main ingredient component. If the content is less than 5 parts by weight, the effect of improving adhesiveness tends to be insufficiently exhibited, and if it exceeds 200 parts by weight, it tends to be difficult to prepare a uniform adhesive sealant. .

  Moreover, when the adhesive sealing material contains silica powder, the mechanical strength of the adhesive sealing material obtained by curing can be improved.

Examples of the silica powder used for such purposes include fumed silica, precipitated silica, calcined silica, and these silica powders such as organosilane, organopolysiloxane, organoalkoxysilane, organohalosilane, and organosilazane. The powder surface-treated with the organosilicon compound can be mentioned. Among these, in order to sufficiently improve the mechanical strength of the cured product, it is preferable to use silica powder having a BET specific surface area of 50 m ² / g or more.

  The content of the silica powder in the adhesive sealing material is preferably 1 to 100 parts by weight and more preferably 1 to 50 parts by weight with respect to 100 parts by weight of the main ingredient component. If the content is less than 1 part by weight, the effect of improving the mechanical strength of the cured product tends not to be sufficiently exhibited, and if the content exceeds 100 parts by weight, the viscosity increases and the handleability decreases. There is a tendency.

  Moreover, when the adhesive sealing material contains quartz powder, the amount of the adhesive sealing material obtained by curing can be increased, and the thermal conductivity can be improved.

  Quartz is a colorless transparent to white powder and has a Mohs hardness of 7. By using quartz having an average particle diameter of 1 to 25 μm, it is possible to effectively suppress deterioration of the silicone rubber over time without causing a decrease in the viscosity of the composition after mixing the two liquids. If the average particle size is smaller than 1 μm, the viscosity of the composition after mixing the two liquids tends to increase remarkably, and the handleability tends to deteriorate. If the average particle diameter exceeds 25 μm, the composition after mixing the two liquids There is a tendency that the viscosity of the product decreases, the shape variation of the joint portion made of the cured product increases, and the dimensional accuracy of the airbag becomes poor. Furthermore, the physical properties of the cured product tend to deteriorate.

  The content of the quartz in the adhesive sealing material is preferably 1 to 200 parts by weight and more preferably 5 to 200 parts by weight with respect to 100 parts by weight of the main ingredient component. If the content is less than 1 part by weight, the effect of suppressing the deterioration of the silicone rubber over time tends not to be sufficiently exhibited, and if it exceeds 200 parts by weight, the elongation of the cured product tends to decrease.

  The two-component addition reaction curable silicone rubber composition exemplified as the adhesive sealant used in the present invention contains at least the main agent, the curing agent, the catalyst, and the specific filler described above.

  Furthermore, in order to improve the adhesiveness, an adhesion-imparting agent may be contained. Examples of such an adhesion-imparting agent include 3-glycidoxypropyltrimethoxysilane, methyltrimethoxysilane, vinyltrimethoxysilane, allyltrimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-aminopropyltrimethoxysilane. Silane coupling agents such as methoxysilane, N- (2-aminoethyl) -3-aminopropyltrimethoxysilane, bis (trimethoxysilyl) propane, bis (trimethoxysilyl) hexane; tetraethyl titanate, tetrapropyl titanate, tetra Titanium compounds such as butyl titanate, tetra (2-ethylhexyl) titanate, titanium ethyl acetonate, titanium acetyl acetonate; ethyl acetoacetate aluminum diisopropylate, aluminum tris ( Tyracetoacetate), alkyl acetoacetate aluminum diisopropylate, aluminum tris (acetylacetonate), aluminum monoacetylacetonate bis (ethylacetoacetate) and other aluminum compounds; zirconium acetylacetonate, zirconium butoxyacetylacetonate, zirconium bis Zirconium compounds such as acetylacetonate and zirconium ethylacetoacetate are listed.

  Moreover, in order to improve the storage stability and handling workability | operativity, it is preferable to contain a hardening inhibitor. Examples of such a curing inhibitor include 3-methyl-1-butyn-3-ol, 3,5-dimethyl-1-hexyn-3-ol, and 3-phenyl-1-butyn-3-ol. Acetylene compounds; enyne compounds such as 3-methyl-3-penten-1-yne and 3,5-dimethyl-3-hexen-1-yne; 1,3,5,7-tetramethyl-1,3,5 , 7-tetravinylcyclotetrasiloxane, 1,3,5,7-tetramethyl-1,3,5,7-tetrahexenylcyclotetrasiloxane, silanol group-capped methylvinylsiloxane, molecular chain both-end silanol Organosiloxane compounds with vinyl groups of 5% by weight or more in one molecule such as group-blocked methylvinylsiloxane / dimethylsiloxane copolymer; benzotriazole, etc. Triazoles, phosphines, mercaptans, hydrazines, and the like.

  As other optional components, for example, inorganic fillers such as fumed titanium oxide, carbon black, diatomaceous earth, iron oxide, aluminum oxide, aluminosilicate, zinc oxide, aluminum hydroxide, silver, nickel; You may contain various additives, such as the filler surface-treated with the said organic acid and organosilicon compound, organopolysiloxane resin, a pigment, and a heat-resistant agent.

  The method for preparing the two-component addition reaction curable silicone rubber composition is not particularly limited, and is prepared by mixing a main agent, a heat generating agent, a curing agent, a catalyst, and optional components as necessary. In addition, when containing an arbitrary component, when this changes in quality by heating mixing, adding after a heating process is preferable. For the preparation, a known kneading apparatus such as a two-roller, a kneader mixer, or a loss mixer can be used.

  Such a two-component adhesive seal material separates the curing agent and the catalyst, the exothermic agent and the substance that reacts with it to generate reaction heat so that the curing reaction starts by mixing the two components. It is important to prepare. If it is a composition which mix | blended the hardening | curing agent (and exothermic agent) with one liquid, a catalyst (and the substance which reacts with it and produces reaction heat) will be mix | blended with the other liquid. The blending of the main agent and other optional components may be appropriately set in consideration of stability and fluidity. It is preferable to prepare the two liquids to have the same fluidity because the handling properties and the applied amount control when the two liquids are mixed and cured are facilitated.

  The viscosity at 25 ° C. immediately after the two-component mixing of the adhesive sealant is preferably 100 to 500 Pa · s. When the viscosity is less than 100 Pa · s, it tends to flow and tends to spread after application or to contain bubbles. On the other hand, when the viscosity exceeds 500 Pa · s, the handleability and application accuracy tend to be poor. Moreover, it is preferable that the viscosity at 25 ° C. of the two liquids before mixing is 50 to 1000 Pa · s, respectively, and if the respective viscosities are approximately equal, the handling property and the application amount control during mixing become easy. And more preferable.

  Moreover, it is preferable that the adhesive sealing material used by this invention has the elasticity whose elongation at break is 800% or more. If the elongation at break is 800% or more, the air bag can sufficiently cope with the expansion of the airbag, so there is no risk of breakage and high airtightness tends to be maintained. The elongation at break is more preferably 1000% or more. Although it is preferable that the elongation at break is large, it is practically 2000% or less.

  Moreover, it is preferable that the hardness according to the JIS K6251 is 5-30. If the hardness is less than 5, deformation when touching the seal portion will increase, and the airtightness of the airbag will tend to be inferior. If it exceeds 30, it will be difficult to fold the entire airbag and storage will deteriorate. Tend to.

  The width of the adhesive sealing material after curing is preferably 5 to 20 mm. If the width is narrower than 5 mm, there is a risk that the post-process sewing performed as necessary may come off from the adhesive seal material. If the width is larger than 20 mm, the joint becomes bulky, so that the storage property is inferior. There is a risk of becoming.

  Moreover, as for the thickness after hardening of an adhesive sealing material, 0.05-2 mm is preferable. If the thickness is less than 0.05 mm, the airtightness of the bag may not be maintained, and if the thickness exceeds 2 mm, the bag may be poorly stored.

  FIG. 1 is a schematic plan view showing an example (side airbag) of the airbag of the present invention. As shown in FIG. 1, the airbag 1 is formed by joining the outer peripheral edges of a first panel 2 and a second panel 3 with a joint portion 5 made of an adhesive seal material.

  Other elements such as panel material (hereinafter referred to as a base fabric) and the shape of the airbag are not particularly limited, and those normally used for airbags may be appropriately selected. Reference numeral 4 denotes a sewing thread, and reference numeral 7 denotes a body mounting bolt hole. In addition, in order to make the structure of the airbag 1 easier to understand, a part of the second panel 3 is cut out by a notch line 8 and the first panel 2 superimposed below is shown.

  A fiber fabric is used for the base fabric. Here, the fiber fabric means a woven fabric woven using fiber yarns, a knitted fabric and a non-woven fabric knitted using fiber yarns.

  The fibers constituting the fiber fabric are not particularly limited, such as natural fibers, chemical fibers, and inorganic fibers. Of these, synthetic fiber filaments are preferred from the viewpoints of versatility and the production process of the base fabric and physical properties of the base fabric. For example, Nylon 6, Nylon 66, Nylon 46, Nylon 610, Nylon 612 and the like, or aliphatic amine fibers obtained by copolymerization and mixing thereof, nylon 6T, nylon 6I, nylon 9T and aliphatic amines Copolymerized polyamide fiber of aromatic carboxylic acid, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate alone or a copolymer thereof, polyester fiber obtained by mixing, ultrahigh molecular weight polyolefin fiber, vinylidene, Chlorine-containing fibers such as polyvinyl chloride, fluorine-containing fibers containing polytetrafluoroethylene, polyacetal fibers, polysulfone fibers, polyphenylene sulfide fibers (PPS), polyether ether Terketone fiber (PEEK), wholly aromatic polyamide fiber, wholly aromatic polyester fiber, polyimide fiber, polyetherimide fiber, polyparaphenylene benzbisoxazole fiber (PBO), vinylon fiber, acrylic fiber One type or two or more types may be appropriately selected from cellulose fibers, silicon carbide fibers, alumina fibers, glass fibers, carbon fibers, steel fibers, and the like. Among these, nylon 66 fiber is preferable from the viewpoint of physical properties, durability, heat resistance, and the like. From the viewpoint of recycling, polyester fibers and nylon 6 fibers are also preferable.

  These fibers include various additives that are usually used to improve spinnability, processability, durability, and the like, for example, heat stabilizers, antioxidants, light stabilizers, anti-aging agents, and lubricants. One or more of a smoothing agent, a pigment, a water repellent, an oil repellent, a concealing agent such as titanium oxide, a gloss imparting agent, a flame retardant, and a plasticizer may be used. In addition, when it is desirable to weave the calami weave, processing such as twisting, bulking, crimping, winding, or gluing may be performed. Further, as the form of the yarn, in addition to the long fiber filament, a spun yarn of short fibers, a composite yarn of these, or the like may be used.

  For example, when the fiber fabric is a woven fabric, it may be a plain weave, an oblique weave (basket weave), a lattice weave (ripstop weave), a twill weave, a knot weave, an entangled weave, an imitation weave, or a composite structure thereof. In some cases, in addition to the two axes of warp and weft, a multi-axis design including 60 degrees oblique may be used, and the yarn arrangement in that case may be the same as the arrangement of warp or weft. Of these, plain weaving is preferable in that the denseness of the structure, the uniformity of physical properties and performance can be ensured.

  Fabric manufacture may be selected from various looms used for weaving ordinary industrial fabrics, for example, shuttle looms, water jet looms, air jet looms, rapier looms, projectile looms, etc. .

  When the fiber fabric is a knitted fabric, a single knitting structure such as a single knitting such as a single tricot knitting, a single cord knitting, a single atlas knitting, a weft knitting such as a flat knitting, a rubber knitting or a pearl knitting, or a combination thereof. And those composed of double tissues. Moreover, when the said fiber fabric is a nonwoven fabric, what is manufactured by a chemical bond, a thermal bond, a needle punch, a spunlace, a stitch bond, a spun bond, a melt blow, wet, etc. is mentioned.

  Further, the single yarn thickness of the yarn used in the present invention may be the same or different, and is preferably in the range of 0.5 to 6 dtex, for example. Further, the strength of the single yarn may be 5.4 cN / dtex or more, preferably 8 cN / dtex or more. The cross-sectional shape of the single yarn of these fibers may be appropriately selected within a range that does not hinder the production of the fabric and the physical properties of the obtained fabric, such as a circle, an ellipse, a flat shape, a polygon, a hollow, and other irregular shapes. Alternatively, a plurality of yarns having different thicknesses or cross-sectional shapes may be integrated by combining, twisting, or the like.

  The total fineness of these fibers is preferably 150 to 1000 dtex, more preferably 235 to 700 dtex. If it is less than 150 dtex, the strength required for the airbag tends to be difficult to obtain. If it exceeds 1000 dtex, the weight becomes too large, and the thickness of the base fabric may increase, resulting in poor bag storage.

The fabric of the present invention comprising these yarns preferably has a basis weight of 190 g / m ² or less and a tensile strength of 650 N / cm or more. If the basis weight and tensile strength are within this range, it can be said that it is light and excellent in physical properties. Here, the basis weight refers to the weight of the base fabric in an unprocessed state before application of an air permeability treatment agent to be described later.

The cover factor when the fiber fabric is a woven fabric is preferably 1500-2500. If the cover factor is less than 1500, the opening of the fabric will be large and it will be difficult to obtain the airtightness of the bag. If the cover factor is greater than 2500, the thickness of the fabric will increase and the bag will not be easily stored. There is a fear. Here, the cover factor means that the warp yarn total fineness is D ₁ (dtex), the warp yarn density is N ₁ (lines / 2.54 cm), the weft total yarn fineness is D ₂ (dtex), and the weft yarn density Is N ₂ (lines / 2.54 cm), (D ₁ × 0.9) ^1/2 × N ₁ + (D ₂ × 0.9) ^1/2 × N ₂ .

  Further, the fiber fabric may be subjected to scouring and heat treatment.

  These fabrics have a non-venting agent for the purpose of improving heat resistance and reducing air permeability. For that purpose, the air-impermeable treatment agent is attached to at least the entire surface of one side of the panel, but intervenes on the panel surface, the gap between yarn bundles constituting the panel, or the gap between single fibers. You may do it. For the reason that damage to the coating can be suppressed even when an external force is applied to the airbag base fabric, it is possible to fabricate the airbag so that the surfaces having the air-impermeable treatment agent of the panel are joined together so that the coated surface is on the inside. preferable.

  The non-aeration treatment agent is a treatment agent that substantially prevents air from passing through. The non-aeration treatment means 8.27.1 A method (fragile type method) in JIS L1096 “General Textile Test Method”. The measured value is 0.0.

  As the air-impermeable treatment agent, the same resin or rubber as that used for the adhesive sealing material can be used. The components that form the air-permeable treatment agent and the adhesive sealing material do not need to be the same, as long as they satisfy the performance as the air-permeable treatment agent. In particular, it is preferable that these are similar components because the compatibility of the interface between the surface of the panel having the air-impermeable agent and the adhesive sealant is improved, and as a result, the adhesiveness is improved. Furthermore, if these are the same components, it is advantageous in terms of quality control and economy.

  The viscosity at 25 ° C. of such an aeration treating agent is preferably in the range of 1,000 to 50,000 mPa · s from the viewpoint of the strength of the coating film to be obtained and blending workability.

  The form before the coating of the air-impermeable treatment agent is not particularly limited, and examples thereof include a solventless type, a solvent dilution type, and a water dispersion type. Of these, the solventless type is preferable in terms of workability and environment.

Moreover, it is preferable that the adhesion amount is 25 g / m < ² > or less by dry weight. The lower limit is preferably 5 g / m ² . If the adhesion amount is less than 5 g / m ² , the air permeability of the fabric tends to be high, and the air bag tends to have a problem of airtightness. If the adhesion amount exceeds 25 g / m ² , the thickness of the fabric increases. Therefore, there is a possibility that a problem arises in the storing property of the airbag. In particular, lightweight, in terms of storability, it is preferred that the amount deposited is 20 g / ^{m 2} or less, further preferably 10 to 20 g / ^{m 2.}

  Furthermore, for the purpose of smoothly deploying the airbag, it is preferable to perform a process for reducing the friction of the coating film obtained by the non-venting agent. Specifically, as the treatment, a method of applying a fine powder such as talc to the coating, a method of coating by treating the treatment agent with a substance that reduces adhesiveness after curing such as an organic titanium compound, and Examples thereof include a method of imparting irregularities to the coating using an embossing device or the like.

  The airbag of the present invention can be manufactured by the following method.

  First, the air-impermeable treatment agent is applied to the base fabric constituting the panel to cover at least one side of the base fabric.

  As coating methods, 1) coating method (knife, kiss, reverse, comma, slot die, lip, etc.), 2) dipping method, 3) printing method (screen, roll, rotary, gravure, etc.), 4) transfer method, etc. (Transfer), 5) Laminating method, and 6) Spraying method. Among these, the coating method is preferable because the range of the application amount that can be set is large.

  Next, the first panel and the second panel are cut out in a desired shape from the base fabric provided with the air-impermeable treatment agent.

  Next, an adhesive seal material is disposed on at least one of the panels. Examples of the method for arranging the adhesive sealing material include a method of applying by a dispenser, screen printing, spraying, and the like, and may be appropriately selected.

  Finally, the surfaces to which the adhesive seal material is applied are overlapped and bonded together by pressure bonding to obtain an airbag.

  Here, after the bonding according to the above, after the adhesive seal material is hardened, an effect of reinforcing the strength of the adhesive seal material is obtained by stitching the bonded portion or the vicinity thereof. If the bonding sealant has sufficient strength and airtightness that does not break even when the airbag is deployed, stitching is not necessarily required, but the expansion of the adhesive sealant is controlled and expanded. Suturing is also preferable in that the shape can be controlled more accurately.

  In particular, it is more preferable to sew the vicinity of the joint portion from the viewpoint of preventing adhesion of the adhesive seal material to the sewing needle and not damaging the joint portion without opening a needle hole. Since the airbag inflated shape is defined by the adhesive seal material, it is more preferable to sew the outside of the joint portion in order to maintain the air bag inflated shape and airtightness.

  What is necessary is just to select suitably the sewing thread | yarn used for a sewing from what is generally called as a synthetic fiber sewing thread | yarn, and what is used as an industrial sewing thread | yarn. For example, nylon 6, nylon 66, nylon 46, polyester, polymer polyolefin, fluorine-containing, vinylon, aramid, carbon, glass, steel and the like may be used, and any of spun yarn, filament twisted yarn or filament resin processed yarn may be used.

  The stitching may be performed by stitches that are applied to ordinary airbags such as main stitching, double chain stitching, one-sided stitching, over stitching, safety stitching, staggered stitching, and flat stitching.

  The thickness of the sewing thread is preferably 700 dtex (corresponding to 20th position) to 2800 dtex (corresponding to 0th position), and the number of stitches is preferably 2 to 10 stitches / cm. If multiple rows of stitch lines are required, the distance between the stitch lines may be about 2.2 to 8.0 mm and a multi-needle type sewing machine may be used. If the sewing part distance is not long, one needle You may sew several times with a sewing machine. In the case where a plurality of cut base fabrics are used as the airbag body, the plurality of cut base fabrics may be overlapped and stitched one by one.

  In addition, by designing the adhesive sealant and air-impermeable treatment agent to have different light transmittance and light reflectance, it is possible to install a light irradiation device or light transmission device on the sewing machine and detect it with a sensor. It becomes possible to sew more accurately. Therefore, a pigment or dye made of titanium oxide, iron yellow, isoindoline, perylene, anthraquinone, phthalocyanine, bengara, carbon black, etc. is applied to one or both of the adhesive sealant and the air-impermeable treatment agent. It is preferable to add such that the transmittance and light reflectance are obtained. If stitching can be accurately performed at an appropriate position by such a method, the loss of arranging the adhesive seal material with an extra width assuming a shift as in the conventional case is reduced.

Examples of other production methods include the following methods.
Similarly, a first base fabric and a second base fabric that have been subjected to aeration treatment are prepared, and an adhesive sealing material is arranged in a desired shape. The desired shape is a shape in which two base fabrics are joined so that an airbag cut out through a subsequent process becomes a bag as shown in FIG.

  Next, similarly to the first manufacturing method, the surfaces to which the adhesive seal material is applied are overlapped and bonded to each other at the position where the adhesive seal material of at least one base fabric is disposed.

  Finally, the airbag is cut out from the two joined base fabrics.

  By cutting out the airbag after joining as in this method, there is no overlap displacement of the opposing panels, so the dimensional accuracy is excellent and no extra part is required for the base fabric, so when the airbag is folded The volume is reduced and the storage property is excellent. In addition, it is possible to accurately position a bolt hole for attachment to a vehicle or the like, and a predetermined expanded shape can be easily obtained. Furthermore, it is also preferable in that the airbag can be manufactured continuously with a series of apparatuses.

  Further, as described above, the joint portion may be sewn. In this case, the suturing may be performed before or after the cutting process.

  The airbag of the present invention includes a strap or restraining cloth called a hanging strap or gas flow adjusting cloth on the inner side and a flap on the outer side of the airbag in order to suppress the protrusion of the airbag to the occupant side and control the thickness at the time of inflation. Etc. may be provided.

  Further, depending on the characteristics of the inflator to be used, a heat-resistant protective cloth or a mechanical reinforcing cloth for protecting from the hot gas may be provided around the inflator outlet. These protective cloths and reinforcing cloths may be made of heat-resistant materials such as heat-resistant fiber materials such as wholly aromatic polyamide fibers, wholly aromatic polyester fibers, PBO fibers, polyimide fibers, and fluorine-containing fibers. Alternatively, a fabric separately produced using a thread thicker than the airbag body base fabric may be used. Moreover, you may use what gave the heat resistant coating agent to the fabric.

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples. In addition, the performance evaluation of the airbag currently performed in the Example followed the following method.

(1) Temperature of adhesive sealing material The temperature of the adhesive sealing material after mixing was measured with a contact-type thermometer.

(2) Elongation at Break of Adhesive Seal Material According to JIS K6251, a test piece of dumbbell No. 3 was collected from the cured adhesive seal material, and the elongation at break was measured.

(3) Deployment test An inflator (tank pressure 150 kPa, Atlantic inflator hybrid inflator) is fixed to the inflator insertion portion of the airbag together with a fixing bracket, and the airbag is deployed at room temperature. The presence or absence of damage was observed.

(4) Airtightness test After injecting pressurized air from the inflator insertion part of the airbag, after the airbag internal pressure reached 50 kPa, the injection of pressurized air was stopped, and after 5 minutes the internal pressure was maintained at 30 kPa. The case where the internal pressure became less than 30 kPa after 5 minutes was marked as x.

(5) Folding thickness The airbag was folded 10 times in a bellows shape substantially parallel to the length direction of the airbag, and the thickness of the airbag when folded was measured.

Example 1
Using nylon 66 filament yarn with a total fineness of 470 dtex, single yarn fineness of 3.5 dtex, single yarn strength of 8.5 cN / dtex, and round cross-section, both warp density and weft density are 45 / 2.54 cm. A plain fabric was woven using a water jet loom. The cover factor is 1851 and the tensile strength is 650 N / cm. This plain fabric was scoured in 90 ° C. hot water containing a surfactant and then heat-set at 185 ° C. for 30 seconds. Next, a two-component addition reaction type solventless silicone rubber composition (viscosity 20 Pa · s at 25 ° C.) was coated on one side of the woven fabric as a non-aeration treatment agent with a knife coater so that the dry weight was 15 g / m ² . Thereafter, heat treatment was performed at 180 ° C. for 2 minutes to obtain a coated fabric having a basis weight of 190 g / m ² .

  The obtained coated fabric was cut into the shape of a side airbag with a laser cutting machine to obtain two panels having the same shape. Subsequently, 20 parts by weight of reduced iron as a heat generating agent and 10% by weight of a highly water-absorbent resin (polyacrylate type) as a water retention agent were separately contained in the two-component addition reaction type silicone rubber. . The two liquids were mixed at a ratio of 1: 1, and applied to the vicinity of the outer peripheral edge of the coating surface of the two panels by a dispenser. The viscosity at 25 ° C. immediately after mixing the sealing materials was 300 Pa · s. Subsequently, the panels were overlapped, pressure-bonded by a flat plate, taken out, and cured at 25 ° C. for 24 hours. The width of the adhesive seal material after curing was 10 mm, and the thickness of the adhesive seal material was 1 mm. The center part in the width direction of the joint portion formed by applying the adhesive sealant is sewn by a main stitch with a needle movement number of 3.5 stitches / cm using a nylon 400 sewing thread of 1400 dtex, and a side airbag is formed. Obtained. By touching the adhesive sealant application part and confirming the development of the elastic performance (elasticity) of silicone rubber and the stability of the shape, and determining the curing, the curing time of the obtained airbag is 5 minutes Met. Furthermore, there was no change in the shape of the adhesive sealing material. In addition, the airbag was deployed without problems, airtightness was high, and storage was compact. The evaluation results are shown in Table 1.

Comparative Example 1
An airbag was obtained in the same manner as in Example 1 except that no exothermic agent was blended in the adhesive sealing material. The obtained airbag required 2 hours for curing. Before curing, the base fabric absorbed moisture and partially expanded and contracted, resulting in wrinkles. Following the wrinkles, the adhesive sealant stretched to increase the thickness and narrow the width, or conversely, the portion was crushed and thinned, and the width increased. When the airbag was deployed, a gas leak from the deformed portion of the adhesive seal material was observed, resulting in a decrease in airtightness. Moreover, it was also inferior in storage property. The evaluation results are shown in Table 1.

  The embodiments of the present invention have been described above, but various design changes can be made without departing from the scope of the present invention. It is not limited to side airbags for protecting automobile occupants, but various occupant protecting airbags, for example, front and rear passenger side airbags for driver and passenger seats, side collision protecting side airbags, rear seat protecting airbags, Headrest airbags for rear-end collision protection, knee and foot airbags for leg and foot protection, infant protection (child seat) mini airbags, submarine phenomenon prevention airbags, air belt bags, pedestrian protection In addition to various uses such as passenger cars, commercial vehicles, buses, motorcycles, etc., it can be applied to various uses such as ships, trains / trains, airplanes, and amusement park facilities as long as they are functionally satisfactory.

It is a schematic plan view which shows an example of the airbag of this invention.

DESCRIPTION OF SYMBOLS 1 Air bag 2 1st panel 3 2nd panel 4 Sewing thread 5 Joining part 6 Annular joining part 7 Bolt hole for vehicle body attachment 8 Notch line

Claims (4)

An airbag formed by bonding two panels with an adhesive sealing material, wherein the adhesive sealing material is a self-heating type. The airbag according to claim 1, wherein an exothermic temperature of the adhesive sealing material is 100 ° C or lower. The airbag according to claim 1 or 2, wherein the adhesive sealing material includes a heat generating agent and a moisture retaining agent. Furthermore, the airbag of Claim 1, 2, or 3 stitched | sutured in the said junction part or the junction part vicinity.

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