JP2010013770A - Woven fabric for airbag and airbag - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a woven fabric for airbags and an airbag having a sewn part causing little expansion of stitches and having excellent robustness. <P>SOLUTION: The woven fabric for airbags has a layer composed of a silicone resin on at least one surface, wherein the woven fabric has a cover factor of ≥750 and not more than 70% of the surface area of the contacting part of the fiber strand (A) constituting the fabric and the fiber strand (B) crossing the strand A is covered with a resin. Preferably, the seam opening of the fabric is ≤6 mm measured in conformity with JIS L-1096-8.21.1A and the increment of the seam opening of the fabric relative to the seam opening before silicone resin treatment is ≤30%. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to an airbag fabric and an airbag that are practically used as an occupant protection device in a side collision of an automobile. More specifically, the present invention relates to a stitched portion that has less seam expansion and is excellent in robustness. The present invention relates to airbag fabrics and airbags.

  In recent years, airbags have rapidly been installed as occupant safety protection devices for automobiles, and airbags for drivers and passengers have been installed in most new models to protect the frontal collision of automobiles. . Further, for side collision protection, there are an increasing number of airbags for the chest and thigh built in the seat, or for the head mounted in the ceiling so as to be deployed along the side window.

  In recent accidents of airbag-equipped vehicles, there are cases where the airbag is deployed while an occupant is seated at a position close to the airbag mounting portion, resulting in an obstacle. For this reason, in North America, legislation that does not harm occupants sitting in close proximity to airbags has been implemented. A system is needed.

  Further, as described above, when the occupant is seated close to the airbag mounting portion, the airbag is deployed within a narrow gap between the mounting portion and the chest, abdomen, or head of the occupant. Therefore, at the time of initial deployment of the airbag, the local portion of the bag body (hereinafter sometimes referred to as the main body) is pulled unevenly due to rapid expansion in a narrow gap, and the seam of the bag body stitching portion is greatly expanded. The hot gas from the inflator may leak and blow out, delaying the inflation of the airbag, and possibly breaking the stitched portion.

  Therefore, it is practical to improve not only the base fabric itself but also the heat resistance of the stitched portion by using a base fabric coated with a heat resistant resin such as silicone. Increasing the heat resistance and thus the robustness of the stitched portion increases the pressure resistance of the bag itself and provides a more secure airbag system.

  Therefore, proposals have been made that pay attention to the stitch opening of the stitched portion. For example, Patent Document 1 proposes an air bag base fabric in which a resin film is coated on at least one surface of a woven fabric made of synthetic fiber filaments of 500 denier or less, and the sliding resistance is 8 to 20 mm. If the sliding resistance is smaller than 8 mm or larger than 20 mm, the burst strength of the bag is lowered. However, in actual airbag deployment, high-temperature gas flows from the inflator, so if the seam hole reaches 8-20mm, not only does the hot gas leak and the bag internal pressure becomes insufficient, but the seam hole in the seam However, the bag itself may be damaged due to the hot gas, and the present invention is a proposal that is difficult to employ practically.

  Patent Document 2 discloses a base fabric for a resin-coated airbag in which the stitch slip resistance of the sewing thread is in the range of 3 to 8 mm. In Patent Document 2, in the weaving of the base fabric, the tension applied to the warp is increased to increase the binding force between the warp and the weft, thereby preventing the yarn from slipping. However, the slipperiness of the yarn constituting the base fabric is determined by various factors such as the fabric design, that is, the thickness of the yarn, the shape of the yarn cross section, and the weave density, and is not uniquely determined. . For example, it is affected by the remaining level of processing oil applied during weaving, processing conditions such as scouring and setting, and the properties of the coating material applied to the base fabric, and the properties immediately after weaving are ensured after coating processing. Not necessarily. Furthermore, in the examples, the numerical values related to the fabric density which seems to have a great influence on the seam slip are not described, and the material design that can obtain the seam slip resistance of 3 to 8 mm is unclear.

Japanese Patent Laid-Open No. 7-164988 JP 2006-63491 A

  The present invention provides an air bag base fabric and an air bag with a small seam opening at a stitching portion.

  That is, the present invention is an airbag fabric having a layer made of a silicone resin on at least one surface, the fabric has a cover factor of 750 or more, and the fiber yarn (A) constituting the fabric, and intersected therewith. The present invention relates to an airbag fabric in which 70% or less of the surface area of the contact portion with the fiber yarn (B) is covered with resin.

  The woven fabric preferably has a stitch opening amount of 6 mm or less based on the JIS L-1096-8.21.1A method, and an increase rate with respect to the stitch opening amount before the silicone resin processing is preferably 30% or less.

  It is preferable that the fiber yarns (A) and (B) have a single yarn fineness of 4 dtex or less.

It is preferable that the application amount of the resin is 10 to 50 g / m ² .

  Moreover, this invention relates to the airbag which consists of the textile fabric for said airbags.

  According to the present invention, the area covered with the resin on the surface of the contact portion between the fiber yarn (A) constituting the woven fabric and the fiber yarn (B) intersecting with the fabric yarn is made 70% or less, so that A coated fabric for an airbag having a small seam opening amount and an airbag comprising the same can be obtained.

  The present invention relates to a fabric for an airbag having a layer made of a silicone resin on at least one surface, the fabric having a cover factor of 750 or more, and a fiber yarn (A) constituting the fabric and a fiber intersecting with the fabric 70% or less of the surface area of the contact portion with the yarn (B) is covered with resin.

  The cover factor of the woven fabric of the present invention is 750 or more, preferably 780 or more, and more preferably 800 or more. When the cover factor is smaller than 750, the woven structure is rough and the seam opening becomes large. In addition, as the cover factor increases, the fabric structure becomes denser and the seam opening decreases, but the fabric tends to be thicker, heavier to fabricate, and harder. It is not preferable. Accordingly, the cover factor is preferably 950 or less.

Here, the cover factor (CF) is an index indicating the density of the woven structure. As shown in the following equation, the weave density N (lines / cm) and the thickness D (dtex) of the warp and weft of the woven fabric. ) And the product. When yarns having different finenesses are used for the warp and the weft of the woven fabric, the cover factor is calculated for each fineness of the warp and the weft and summed to obtain the cover factor of the entire woven fabric.
CF = Nw × √Dw + Nf × √Df
Here, Nw and Nf are the weave density of warps and wefts (lines / cm)
Dw and Df are warp and weft thickness (dtex)

  In the woven fabric of the present invention, 70% or less of the surface area of the contact portion between the fiber yarn (A) constituting the woven fabric and the fiber yarn (B) intersecting with the fiber yarn (A) is covered with resin. In other words, more than 30% of the contact portion surface area is not resin-coated. In a woven fabric formed by warp and weft crossing each other up and down, for example, when resin is applied from the fiber yarn (A) side, the resin first penetrates into the fiber yarn (A). It passes through the fiber yarn (A), eventually reaches the surface of the fiber yarn (B) intersecting with the fiber yarn (A), and adheres to the surface. At this time, the more resin that adheres to the surface of the fiber yarn (B), the easier it is to slip at the intersection (contact portion) of the fiber yarns (A) and (B). The opening becomes larger. That is, in the present invention, it is important to prevent the applied resin from penetrating into the inside of the fabric as much as possible. In particular, when a portion of the contact surface area larger than 70% is covered with the resin, the seam opening is performed. It was made by finding out that it will become much larger.

  In the present invention, the ratio of the surface area of the contact portion covered with the resin (hereinafter referred to as coverage) is 70% or less, preferably 60% or less, and preferably 50% or less. More preferred. The smaller the coverage, the better. However, even if the coverage is smaller than 20%, there is not much influence on the restraint at the intersection, so the lower limit is preferably 20%. If the coverage is greater than 70%, that is, if about 2/3 or more of the entire width of the fiber yarn is coated with resin, it becomes slippery at the intersection of the fiber yarns (A) and (B), and the restraint is low. Therefore, the seam opening when stitched is increased.

In addition, the resin coverage here is calculated | required as follows.
First, a warp or weft (fiber yarn (A)) of a woven fabric provided with a resin layer is pulled out, and an exposed portion of the yarn (fiber yarn (B)) intersecting with the SEM photograph (from the resin-coated surface) Take a backscattered electron image. In the reflected electron image, the resin-attached surface has a higher luminance, so that it can be distinguished from the synthetic fiber surface. Using this, the total width (AW) of the fiber yarn (B) and the width (FW) of the dark color portion where the resin is not adhered are measured, and ((AW−FW) / AW) × 100 Calculate from%.

  The woven fabric of the present invention preferably has a seam opening of 6 mm or less based on the 8.21.1A method of JIS L-1096. It is more preferably 5 mm or less, and further preferably 4 mm or less. The magnitude of the stitch opening amount affects the retention of the air bag internal pressure because it directly affects the amount of gas escaped from the stitched portion. In addition, because the temperature of the fabric material around the seam rises due to the hot gas leaking from the enlarged seam hole, depending on the temperature of the hot gas and the amount of leak, the fabric material may melt, and the airbag may break at the stitched portion. is there. Therefore, the amount of stitch opening is preferably as small as possible. However, since a woven fabric composed of warps and wefts is used, the stitch opening does not become zero, and the lower limit is, for example, about 0.5 to 1 mm. preferable.

  Moreover, in this invention, it is preferable that there is little change of the stitch opening amount before and after silicone resin coating. As a resin, a silicone material is generally used because it is excellent in heat resistance and durability. As is well known, a silicone material contains a component that imparts smoothness. For this reason, the amount of stitch opening after coating of a fabric coated with a silicone material tends to be larger than that before coating. Depending on the design specifications of the fabric, the type of coating material and the amount of coating, etc. There was also an expansion. However, in the present invention, by setting the coverage to a specific range, even when a silicone resin is used, the change in the stitch opening amount of the fabric before and after coating is small. That is, regardless of the amount of the covering material, by setting the covering rate to a specific value, the characteristics of the fabric itself can be maintained, and the seam expansion can be stably suppressed.

  The increase rate of the stitch opening amount (OA) after coating with respect to the stitch opening amount (OB) before resin coating is preferably 30% or less, more preferably 20% or less, and more preferably 10% or less. Is more preferable. If the increase rate is larger than 30%, it is considered that the penetration of the resin into the fabric is increased. Although it can be said that the degree of penetration of the resin is constant over a wide area, the degree of penetration is not necessarily constant in a narrow area such as a sewing site, and as a result, there is a tendency for the variation in the stitch opening amount to increase. . That is, if the rate of increase of the stitch opening amount is greater than 30%, the stitch opening of the fabric is difficult to be constant, and it is difficult to obtain an airbag having a stable deployment characteristic. On the other hand, if the amount of stitch opening is 30% or less, the resin permeation itself is small, so there is little variation in the degree of penetration, and the stitch opening of the coated fabric tends to be stable, resulting in stable development characteristics. An airbag can be provided. The lower limit value of the rate of increase in the stitch opening amount is preferably zero. The increase rate of the stitch opening amount referred to here is obtained from the calculation formula of (OA−OB) / OB × 100 (%).

  Here, as a method of making the covering ratio 70% or less, 1) a method of making a woven fabric structure in which the resin hardly penetrates into the inside of the woven fabric, 2) a method of making the resin itself difficult to penetrate, and 3) a resin infiltrated. Examples of the method include coating by a difficult method. For example, 1) As the woven structure, a) a dense woven fabric having a large cover factor (for example, 850 or more), and b) a woven fabric using fiber yarns having a small single yarn fineness may be used. It is done. 2) Examples of the resin include a) using a high viscosity resin (for example, 50 Pa · s or more). 3) As the coating method, a) Applying a high tension to the fabric in the coating process (for example, warp direction), b) Applying a coating method with a low pressing force on the fabric coating surface, such as a transfer method, a gravure method, C) A method of laminating and covering films, sheets and the like. Among these, it is preferable to use a fiber yarn having a small single yarn fineness, to apply tension to the fabric during processing, and to use a coating method by a transfer method or a gravure method. In particular, it is preferable to use a fiber yarn having a small single yarn fineness in that the stitch opening can be reduced without adding any contrivance to the characteristics of the covering material or the covering method.

  As described above, it is preferable that the single yarn fineness of the fiber yarn is small. It is more preferably 4 dtex or less, further preferably 3.5 dtex or less, and particularly preferably 3 dtex or less. The lower limit is preferably 0.5 dtex. When the single yarn fineness is 4 dtex or less, the resin applied to the fabric surface does not easily penetrate into the fabric, and the restraint at the intersection of the warp and weft of the fabric tends to be easily maintained. When the single yarn fineness is less than 0.5 dtex, the fineness becomes too thin, and troubles in the manufacturing process such as weaving, cutting, and sewing tend to occur.

  The total fineness of the fiber yarn is usually the thickness of the fiber yarn used in the airbag, and may be selected according to the required base fabric specifications and physical characteristics. Especially, it is preferable that it is 200-1000 dtex, and it is more preferable that it is 300-900 dtex. If the total fineness is less than 200 dtex, the strength required for the airbag tends to be difficult to obtain. If the total fineness exceeds 1000 dtex, the weight becomes too large and the thickness of the base fabric increases, resulting in poor bag storage. There is a tendency.

  Furthermore, the cross-sectional shape of the single yarn may be appropriately selected within a range that does not hinder the manufacturing process of the yarn and the fabric, the physical properties of the obtained fabric, such as a circle, an ellipse, a flat shape, a polygon, a hollow, and other irregular shapes. In addition, an air bag having higher pressure resistance is obtained as the strength of the fiber yarn is higher, but is preferably 8 to 15 cN / dtex, and more preferably 9 to 13 cN / dtex.

  The breaking elongation of the fiber yarn is preferably 15 to 30%.

  The woven fabric of the present invention may be composed of any of plain weave, oblique weave (basket weave), lattice weave (ripstop weave), twill weave, leopard weave, tangle weave, imitation weave, or a composite structure thereof. Of these, a plain weave is preferable in that the denseness of the woven structure, the uniformity of physical properties and performance can be secured. If necessary, in addition to the two axes of warp and weft, a multi-axis design including 60 degrees obliquely may be used, and the arrangement of the threads in this case may be the same as that of the warp or weft. Moreover, you may use the multiple fabric by the loom which mounts a jacquard apparatus.

  What is necessary is just to select the manufacture of the said textile fabric suitably from the various looms used for weaving a normal industrial textile fabric. Examples include shuttle looms, water jet looms, air jet looms, rapier looms, and projectile looms.

  Moreover, the said fiber yarn is not specifically limited, such as a natural fiber, a chemical fiber, and an inorganic fiber. Of these, synthetic fiber filaments are preferred because of their versatility and from the standpoints of fabric manufacturing process and fabric physical properties. Specific examples include nylon 6, nylon 66, nylon 46, nylon 610, nylon 612, etc., or aliphatic polyamide fibers obtained by copolymerization or mixing thereof, nylon 6T, nylon 6I, nylon 9T. Copolymerized polyamide fiber of aliphatic amine and aromatic carboxylic acid, polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, or the like, or a polyester fiber obtained by copolymerization or mixing thereof, High molecular weight polyolefin fibers, chlorine-containing fibers such as vinylidene and polyvinyl chloride, fluorine-containing fibers containing polytetrafluoroethylene, polyacetal fibers, polysulfone fibers, polyphenylene sulfide fibers PPS), polyether ether ketone fiber (PEEK), wholly aromatic polyamide fiber, wholly aromatic polyester fiber, polyimide fiber, polyetherimide fiber, polyparaphenylenebenzbisoxazole fiber (PBO), vinylon Fiber, acrylic fiber, cellulose fiber such as cotton, hemp, kenaf fiber, biodegradable fiber represented by polylactic acid, oxalic acid, silicon carbide fiber, alumina fiber, glass fiber, carbon fiber, Examples include steel fibers. From these, one kind or two or more kinds may be appropriately selected. Among these, nylon 66 fibers are preferably used in terms of physical characteristics, durability, heat resistance, and the like. From the viewpoint of recycling, polyester fiber and nylon 6 fiber are preferable.

  These fiber yarns have various additives that are usually used to improve spinnability, processability, durability, etc., such as heat stabilizers, antioxidants, light stabilizers, anti-aging agents. In addition, one or more of a lubricant, 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 can be blended.

  The woven fabric is used as a base fabric for airbags, and is a silicone resin or rubber satisfying heat resistance, wear resistance, adhesion to the base fabric, flame retardancy, non-adhesiveness, etc. These are collectively referred to as silicone resin). Although the silicone material contains a component that imparts smoothness, according to the present invention, the seam opening of the stitched portion is very small.

  Examples of silicone resins include two-component thermosetting silicone resins or rubbers by addition reaction, modified products of silicones and polyurethane resins or rubbers, and copolymers of silicones and fluorine resins or rubbers. can give. Furthermore, another resin having a high compatibility with the silicone resin or the like may be mixed so as not to exceed half.

  Specifically, the silicone resin is a hydrogen atom bonded to at least three silicon atoms in one molecule as a crosslinking agent component, such as a diorganopolysiloxane having at least two alkenyl groups in one molecule as a main component. (SiH group) -containing organohydrogenpolysiloxane, platinum fine powder as catalyst, chloroplatinic acid, platinum-vinylsiloxane complex, etc., curing retarder, alkyne alcohols, enyne compounds, etc., silica as reinforcing filler Fine powders, organic titanium compounds, epoxy group-containing organosilicon compounds, etc. as adhesion improvers with fabrics, other additives, fillers such as quartz powder, diatomaceous earth, calcium carbonate, nickel oxide, cerium oxide, hydroxide Heat resistance imparting agents such as cerium and iron oxide, bengara, titanium oxide, carbon Such as a pigment, such as black, consisting of mixed solution.

  The viscosity of the resin after preparation is preferably 10 Pa · s or more, and more preferably 20 Pa · s or more. By increasing the viscosity of the resin liquid, it is possible to suppress the penetration of the fabric into the fiber yarn, but when the viscosity is less than 10 Pa · s, the penetration into the fiber yarn tends to increase, As a result, the opening of the seam increases. However, if the viscosity is too high, the coating processability deteriorates, so the upper limit of the viscosity is preferably about 200 Pa · s.

The amount of the resin applied may be such that the air permeability of the fabric can be ensured. The non-aeration means a measured value of 0.0 in the 8.27.1 A method (fragile type method) in JIS L1096 “General Textile Test Method”. Among them, it is preferably 10 to 50 g / ^{m 2,} and more preferably 20 to 40 g / ^{m 2.} If the applied amount is less than 10 g / m ^2, it tends to be difficult to obtain air permeability and flame retardancy depending on the woven structure, and if it exceeds 50 g / m ² , the air permeability is excellent. The fabric weight of the fabric tends to be heavy, and the foldability tends to decrease.

  The resin is applied to at least one side of the fabric. Application methods include 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. (Transfer), 5) laminating method, 6) spraying / injecting method and the like. Of these, the gravure method, the transfer method, or the laminating method is preferable in that the resin hardly penetrates into the fiber yarn.

  The property of the resin as a liquid is a solvent-free type, a solvent type, a water dispersion type, a water emulsification type, depending on the coating amount, the coating method, the workability and stability of the material, the properties required as a coating material, etc. It can be selected appropriately from a water-soluble type. Especially, it is preferable that it is a solventless type from the point of the environment in a manufacturing process, a covering work process, etc.

  For the resin, various additives usually used for improving processability, adhesiveness, surface characteristics or durability, for example, a crosslinking agent, an adhesion-imparting agent, a reaction accelerator, a reaction retarding agent, a heat-resistant stability. Agent, antioxidant, light stabilizer, anti-aging agent, lubricant, smoothing agent, anti-blocking agent, pigment, water repellent, oil repellent, concealing agent such as titanium oxide, gloss imparting agent, flame retardant, plasticizer, etc. One kind or two or more kinds may be mixed.

  Moreover, it is preferable that tension is applied in the warp direction and / or the weft direction of the woven fabric when the resin is coated because the resin can hardly penetrate into the fiber yarn. In particular, it is preferable to apply tension in the warp direction of the woven fabric in terms of easy adjustment and easy manifestation of the effect. What is necessary is just to select the tension | tensile_strength added to a textile fabric according to textile fabric structure (the thickness of a thread | yarn, a woven density, a lateral width), the application quantity of resin, etc. Especially, it is preferable that it is 5-30 N / cm as tension | tensile_strength per fabric width. When the tension is less than 5 N / cm, the effect of applying the tension is small, and the resin easily penetrates into the inside of the fabric. When the tension exceeds 30 N / cm, the tension becomes too high, and the amount of properties such as fabric weight is changed and the coating treatment is performed. Deterioration of physical properties due to friction with tools tends to occur.

  The resin only needs to be present on the surface of at least one side of the woven fabric, and is interposed in the gap portion of the yarn bundle constituting the base fabric or the gap portion of the single fiber yarn within a range not exceeding 70% coverage. Also good.

  In order to improve the adhesion between the fabric and the resin, the surface of the fabric may be pretreated such as a primer treatment in advance. Furthermore, in order to impart or improve physical properties such as heat resistance, anti-aging properties, and oxidation resistance to the resin, for example, after the resin coating, drying, crosslinking, vulcanization, etc. are performed with hot air treatment, pressure heat treatment, You may carry out by high energy processing (a high frequency, an electron beam, ultraviolet rays, etc.).

  The present invention also relates to an airbag made of the woven fabric. The specifications of the airbag of the present invention, that is, the shape, dimensions, capacity, the number of cutting pieces to be configured, etc. include the mounting site, the storage space, the impact absorption performance of the occupant, the output of the inflator, and the harm to the occupant during initial deployment You may choose according to.

  The stitching specification of the stitched portion in the airbag of the present invention is performed by stitches that are applied to normal airbags such as main stitching, double chain stitching, one-sided stitching, overlock stitching, safety stitching, staggered stitching, and flat stitching. Just do it. In particular, it is preferable to perform the main sewing or the double chain sewing in that a sewing machine corresponding to a thick sewing thread for an airbag is manufactured and the sewing work is simple. If multiple rows of stitch lines are required, the distance between the stitch lines may be about 2 mm to 6 mm and a multi-needle type sewing machine may be used. If the sewing part distance is not long, a single needle sewing machine may be used. Multiple stitches may be sutured. Further, the number of moving hands is preferably 2 to 8 needles / cm, and more preferably 3 to 6 needles / cm. When the number of moving needles is less than two, there is a tendency that the strength of the stitched portion cannot be sufficiently obtained. When the number of stitches exceeds eight stitches, high strength of the stitched portion is easily obtained, but the stitched portion rises and becomes hard, and the airbag The folding volume tends to be less likely to be small. Furthermore, the tact time in the sewing process also becomes long, and the productivity tends to decrease.

  What is necessary is just to select suitably the sewing thread used for the said sewing from what is generally used as a synthetic fiber sewing thread and an industrial sewing thread. For example, nylons such as nylon 6, nylon 66, and nylon 46, polyesters, polymer polyolefins, and vinylon are available. Among these, nylon and polyester are preferable in terms of high strength, and nylon is more preferable in terms of high hook strength. In addition, the form of the yarn may be any of spun yarn, filament yarn, and bulky processed yarn, and single or plural fiber yarns may be twisted, twisted, wound, or twisted.

  Furthermore, if necessary, in order to impart smoothness, convergence, flexibility, etc. to the sewing thread, various resin processing or oiling processing, for example, a smoothing agent such as silicone resin, fluorine resin, polyolefin resin, A sizing agent such as polyurethane resin, acrylic resin, nylon resin, polyester resin, polyurea resin, polyvinyl alcohol resin, vinyl acetate resin, or epoxy-modified resin may be applied. What is necessary is just to select these resin adhesion amounts from the performance calculated | required and the resin characteristic to be used. For example, it is preferably 2 to 20% based on the fiber weight. Furthermore, in order to impart performance such as heat resistance, inorganic fillers, for example, fine particles (including nano-sized particles) such as silica, bentonite, carbon, silicon carbide, metals, metal oxides, fine needles ( Or the like may be used by mixing with the resin solution. These processing treatments may be applied to the fiber yarns constituting the sewing thread, may be applied after the sewing thread is created from the fiber yarns, or may be applied at both stages, and the processability as a sewing thread may be applied. It may be selected in consideration of physical characteristics.

  In addition, if necessary, in order to prevent gas leakage from the seam from the outer peripheral stitching part more thoroughly, a sealing agent, an adhesive, an adhesive, etc. may be used between the seam and the seam allowance. It may be applied, spread or laminated on the part.

  In the airbag of the present invention, in order to absorb energy when the occupant comes into contact with the airbag, one or a plurality of exhaust holes, for example, a hole having a diameter of 10 to 80 mm or a corresponding area, or the exhaust performance thereof. You may provide the slit, membrane | film | coat, valve, etc. which are corresponded to. A reinforcing cloth may be joined or laminated around the exhaust part. Furthermore, a fixed string may be provided inside the airbag in order to suppress the impact of the airbag protruding on the occupant's head and face, and to control the thickness during inflation. Further, when a part of the occupant comes into contact, in order to prevent the internal pressure of the main inflating portion from rapidly increasing, the sub inflating portion is connected to the outside of the main inflating portion or is adjacent to the main inflating portion via a fracture portion. May be provided.

  About the airbag of this invention, according to the characteristic of the inflator to be used, you may provide a heat-resistant protective cloth and a mechanical reinforcement cloth for protecting from a hot gas around an inflator jet outlet as needed. These protective cloths and reinforcing cloths are 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, fabrics such as woven fabrics separately produced using yarns that are the same as the airbag main body or thicker than the base fabric for the main body may be used, or the fabrics such as the woven fabrics provided with a heat resistant coating material. May be used.

  The folding method when storing the air bag is also from the center like a driver's seat bag, left and right symmetrical folding screen folding, how to fold it toward the center from multiple directions, roll folding like a passenger seat bag, The folding may be performed by accordion folding, folding screen-like zigzag folding, or a combination thereof, or alligator folding such as a side bag with a built-in seat.

  The airbag of the present invention is a bag for protecting various passengers, for example, for front and rear collision protection of driver and passenger seats, for side collision protection, for rear seat protection, for rear-end collision protection headrest bags and for occupant protection, legs. Knee bags and foot bags for child / foot protection, mini bags for child protection (child seats), air belt bags, passenger cars for protecting pedestrians mounted on cowl tops and bumpers, commercial vehicles, buses, trucks In addition to various uses such as motorcycles, if it is functionally satisfactory, it can be applied to various uses such as ship transportation, railway transportation such as trains and trains, airplanes such as airplanes and helicopters, and playground equipment in amusement parks. .

EXAMPLES Hereinafter, the present invention will be described more specifically based on examples. In addition, the evaluation method of the resin coating rate performed in the Example, the stitch opening amount and increase rate of a textile fabric, and an airbag deployment test is shown below.

(1) Resin coverage The exposed portion of the fiber yarn (B) that intersects the yarn by removing a part of the fiber yarn (A) that is the warp or weft of the fabric coated with the silicone resin. Was taken from the resin-coated surface. A scanning electron microscope S-3000N manufactured by Hitachi High-Technologies Corporation was used for photographing. The total width (AW) of the fiber yarn (B) observed as the trace of the fiber yarn (A), and the central portion where the resin is not attached (the dark portion visible in the central portion in the SEM photograph shown in FIG. 1) The width (FW) was measured and the coverage was determined from (AW-FW) / AW) × 100%. The case where the fiber yarn (A) was used as the warp and the case where the weft was used was performed at N = 5, and the total average value was taken as the coverage.

(2) Amount of stitch opening and rate of increase About the largest one of the expanded stitch holes when the tensile load reaches 588 N in the sample shape specified in JIS L-1096 method 8.21.1A N = 3 was measured for each of the warp direction and the weft direction of the fabric, and the total average value was defined as the stitch opening amount. The sewing specifications were such that the upper thread and the lower thread both used nylon 66 fiber 5th thread as the sewing thread, the number of stitches was 3.5 stitches / cm, and one row of main stitches. Further, the rate of increase in the stitch opening amount of the woven fabric before and after resin coating was determined by measuring the stitch opening amount before coating (OB) and after coating (OA) by the above-described evaluation method, and (OA-OB) / OB × 100. (%).

(3) Airbag deployment test The deployment test was conducted by assembling a module using a Daicel inflator (model ZA, 2-stage type, output 160/220 kpa), a fixture, and a resin case. After the module was preheated at 100 ° C. for about 5 hours, a deployment test (N = 3) was performed, and the deployment state of the airbag and the state of the outer peripheral suture portion after deployment were observed.

(4) Manufacturing method of driver's seat airbag The manufacturing method of the driver's seat airbag used for the evaluation is shown below.
The base fabric shown in each example was used as a base fabric for an air bag body. Two circular main panels having an outer diameter of 690 mm were cut from the base fabric. An inflator attachment port with a diameter of 67 mm was formed in the center of one main body panel, and two exhaust holes (a pair of left and right) were opened at a position of 120 mm on a line 45 degrees obliquely upward from the center of the attachment port. Further, as a reinforcing fabric, obtained by applying 35 g / m ^{2 of} silicone resin to a non-coated base fabric having the same specifications as the base fabric for the main body and a base fabric having a weaving density of 18 / cm using 470 dtex of nylon 66 fibers. A coated base fabric was prepared. As the reinforcing cloth for the inflator attachment port, three annular cloths A having an outer diameter of 210 mm and an inner diameter of 67 mm were cut from the non-coated base cloth and one from the coated base cloth. Further, two annular cloths B having an outer diameter of 90 mm and an inner diameter of 30 mm were cut from the coated base cloth as exhaust hole reinforcing cloths.

  The obtained three non-coated annular fabrics A were superposed on the inflator attachment port, and sewn into a circle at positions of φ126 mm and φ188 m from the inside. Furthermore, one coated annular cloth A having the same shape was overlapped from above and sewn in a circular shape on the main body base cloth at a position of φ75 mm. In addition, one annular cloth B was overlaid on each of the exhaust holes and sewn on the main body panel. The reinforcing cloths of the annular cloth A and the annular cloth B were overlapped at a position parallel to the thread axis of the main body panel to be sewn. In addition, the annular cloth A is provided with four bolt holes of φ5.5 mm at a distance between the holes of 68 mm. For sewing the annular reinforcing fabrics A and B to the main body panel, the upper thread and lower thread are both 5th thread (1400 dtex for nylon, thickness equivalent to 1400 dtex for nylon other than nylon). / Cm. Further, the two main body panels are shifted by 45 degrees from the thread axis of the panels, and the sewing surfaces of the annular reinforcing cloth are overlapped with each other, and a sewing thread which is the fifth thread of nylon 66 fiber is used for the outer periphery (upper thread). The lower thread has the same thickness), the number of stitches is 3.5 stitches / cm, the stitch line is 2.4 mm, the seam allowance is 20 mm, and stitched in two rows of double ring stitches to produce a circular airbag with an inner diameter of φ650 mm. The produced airbag was inverted from the inflator attachment port and subjected to a burst test.

Example 1
Using nylon 66 fiber (round cross section) with a thickness of 470 dtex / 136 f (single yarn fineness 3.5 dtex), strength 8.5 cN / dtex, and elongation at break 23%, fabric is made by plain weaving and scouring and setting It was. Next, Rhodorsil TCS7534 (manufactured by Blue Star Silicone Co., Ltd., two-component addition reaction type solventless silicone resin, viscosity after preparation of 45 Pa · s) is coated on one side of the obtained woven fabric by a knife coat method, and the temperature is 1 The coated fabric was obtained by heat treatment for minutes. The weaving density of the woven fabric was 20 pieces / cm for both warp and weft, the cover factor was 867, and the coating amount was 25 g / m ² . Using this coated fabric, an airbag was prepared in accordance with the above production method and subjected to a deployment test. Table 1 shows the coverage, the stitch opening, and the characteristics of the airbag. As can be seen from Table 1, since the resin coverage was low, the amount of seam opening and the rate of increase were low, the airbag inflated without any problem in the deployment test, and no meshing of the outer peripheral stitched portion after deployment occurred.

Example 2
Using nylon 66 fibers (round cross section) with a thickness of 350 dtex / 136 f (single yarn fineness 2.6 dtex), strength 8.5 cN / dtex, and elongation at break 25%, fabric is made by plain weaving, and scouring and setting are performed. It was. Next, a coated fabric was obtained in the same manner as in Example 1. The weaving density of the woven fabric was 22.8 / cm in both warp and weft, the cover factor was 853, and the coating amount was 20 g / m ² . An airbag was prepared according to the above manufacturing method, and a deployment test was performed. Table 1 shows the coverage, the stitch opening, and the characteristics of the airbag. As can be seen from Table 1, by reducing the fineness of the single yarn, the resin coverage is further reduced as compared with Example 1. Since the resin coverage was low, the amount of seam opening and the rate of increase were sufficiently small, and there was no problem in the airbag deployment test.

Example 3
In addition to using a woven fabric with a weaving density of 18.1 pcs / cm for both warp and weft and a cover factor of 785, and a tension in the warp direction of the woven fabric of 2450 N (16 N / cm) during coating processing Obtained a coated fabric and an airbag in the same manner as in Example 1. As can be seen from Table 1, because the tension was applied, the resin coverage was low despite the low woven density. Since the resin coverage was low, both the stitch opening amount and the increase rate were small, and there was no problem in deploying the airbag.

Example 4
Using nylon 66 fiber (round cross section) having a single yarn fineness of 6.5 dtex, DC3730 (manufactured by Dow Corning Co., Ltd., two-component addition reaction type solventless silicone resin, viscosity after preparation of 180 Pa) A coated woven fabric and an airbag were obtained in the same manner as in Example 1 except that s) was used and the resin was applied by a roll transfer method. The amount of resin applied was 15 g / m ² . As can be seen from Table 1, since the resin was applied by a processing method with little penetration into the fiber, the coverage was very small. Since the resin coverage was low, both the stitch opening amount and the increase rate were small, and there was no problem in deploying the airbag.

Comparative Example 1
In addition to using nylon 66 fiber (round cross section) with a single yarn fineness of 6.5 dtex, using a woven fabric with a weaving density of 18.1 / cm in both weft density and weft and a cover factor of 785 Obtained a coated fabric and an airbag in the same manner as in Example 1. Since the covering rate exceeds 70%, both the stitch opening amount and the increasing rate are very large. In some airbag deployment tests, the peripheral seam was damaged.

Comparative Example 2
In addition to using nylon 66 fiber (round cross section) with a single yarn fineness of 6.5 dtex, and using a woven fabric with a weaving density of 16.9 yarns / cm in both weft density and weft and a cover factor of 733 Obtained a coated fabric and an airbag in the same manner as in Example 1. Since the cover factor of the woven fabric is small and the coverage of the resin is large, the stitch opening amount and the increase rate are extremely large. In the airbag deployment test, all the bags were damaged.

It is an example of the SEM photograph (magnification 50) after removing the warp in the silicone resin coating surface of the textile fabric of the present invention. It is an example of the SEM photograph (magnification 50) after removing the warp in the silicone resin coating surface of the conventional textile fabric.

Claims (5)

A fabric for an airbag having a layer made of a silicone resin on at least one side, the fabric having a cover factor of 750 or more, and the fiber yarn (A) constituting the fabric and the fiber yarn intersecting therewith A fabric for an airbag in which 70% or less of the surface area of the contact portion with (B) is covered with a resin. 2. The fabric according to claim 1, wherein the fabric has a stitch opening amount of 6 mm or less based on JIS L-1096-8.21.1A method, and an increase rate with respect to the stitch opening amount before the silicone resin processing is 30% or less. Airbag fabric. The fabric for an airbag according to claim 1 or 2, wherein the fiber yarns (A) and (B) have a single yarn fineness of 4 dtex or less. The application amount of the resin, 10 to 50 g / ^{m 2} and is claim 1, 2 or 3 fabric for an air bag according. The airbag which consists of the textile fabric for airbags of Claim 1, 2, 3 or 4.