Polyester base fabric for airbags

Abstract

The present invention addresses the problem of providing a polyester base fabric for airbags, said polyester base fabric using polyester fibers that are capable of reducing the cost, while maintaining the mechanical characteristics required for a base fabric for airbags, and exhibiting high restraint performance for receiving an occupant when expanded, said restraint performance being maintained at high level even if the polyester base fabric is changed with the passage of time. The present invention provides, as a means for solving the problem, a polyester base fabric for airbags, said polyester base fabric being provided with a resin on at least one surface, while being characterized in that: the crimp ratio of the polyester base fabric is optimized; and the number of scrubbing tests after a 408-hour deterioration treatment at 70°C at 95% RH is 400 or more.

Description

[Technical Field]

[0001] The present invention relates to a polyester base fabric for airbags. More specifically, the present invention relates to a polyester base fabric for airbags that has high restraint performance for receiving an occupant when deployed while maintaining the mechanical properties of an airbag, and further, that maintains this performance at a high level even with aging. [Background technology]

[0002] In recent years, airbags have become widely used as occupant safety protection devices in automobiles, and their installation locations have expanded to include driver's seat, passenger seat, thigh protection airbags built into the seat, and curtain airbags that deploy along the side windows, resulting in an increasing amount of airbag fabric used per automobile. The fabrics currently used for airbags are primarily made of polyamide fibers, particularly nylon 6,6 fibers, which have properties suitable for airbag fabrics. However, nylon 6,6 fibers are relatively expensive, and the cost burden is increasing as airbags become more widespread. Therefore, there is a demand for fabrics made of polyester fibers, which have lower raw yarn costs than nylon 6,6 fibers.

[0003] However, airbag fabrics are required to have various properties to protect automobile occupants. For example, airbag fabrics need not only to be deployable but also to have various mechanical properties necessary to accommodate occupants, and they are also required to maintain sufficient performance in accelerated aging tests that simulate the usage environment. To meet these requirements, for example, Patent Document 1 proposes an airbag fabric that specifies the resistance to rubbing after wet heat degradation, thereby maintaining performance after aging. However, all of these fabrics are made of polyamides such as nylon 6,6, and polyester fabrics have not been substantially disclosed. Compared to nylon 6,6 fiber, the properties of polyester fiber are less favorable for use in airbag fabrics, and airbag fabrics using polyester fiber are not yet widely used. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] China Patent Publication 103132333B Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made against the background of the above-mentioned problems of the conventional technology, and uses polyester fibers that can reduce the cost burden, and has high restraint performance to receive the occupant at the time of deployment while maintaining the mechanical properties of the airbag base fabric. It is an object of the present invention to provide a polyester base fabric for airbags that maintains the performance at a high level even if it changes over time. [Means for solving the problem]

[0006] The present inventors have conducted extensive research to solve the above problems and have finally completed the present invention.

[0007] 1. A polyester base fabric for airbags having a resin disposed on at least one surface, The crimp rate of the yarns constituting the polyester base fabric for airbags is 1.0% to 12.0% for both warp and weft yarns. A polyester base fabric for airbags, characterized in that: 2. A polyester base fabric for airbags according to the above item 1, having an energy allowance (EA) per unit weight calculated by the following formula 1 of 5.0 (J / g) or less. Equation 1: EA(J / g)=(EW+EF) / W where EW (J / m 2 ) is the hysteresis energy per unit surface area in the warp direction when stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm. EF(J / m 2 ) is the hysteresis energy per unit surface area in the weft direction when stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm. W (g / m 2 ) is the weight of the base fabric per unit area, Each is shown. 3. A polyester base fabric for airbags as set forth in 1. or 2. above, which has a restraint capacity utilization rate (RR) calculated by the following formula 2 of 85% or more. Equation 2: RR(%) = RW / BW + RF / BF where RW (mm) is the stretch of the base fabric in the warp direction when loaded with 120N / cm. BW (mm) is the elongation of the base fabric at break in the warp direction. RF (mm) is the elongation of the base fabric in the weft direction when loaded with 120N / cm. BF (mm) is the elongation of the base fabric at break in the weft direction. Each is shown. 4. A polyester base fabric for airbags according to any one of 1 to 3 above, which can be scrubbed 500 times or more in an initial scrub test. 5. A polyester base fabric for airbags according to any one of 1 to 4 above, which has a cover factor of 1900 to 2600. 6. Weight is 300g / m 2 6. The polyester base fabric for an airbag according to any one of 1 to 5 above, which is as follows: 7. The resin used is a silicone resin and is 5 g / m 2 More than 50g / m 2 7. The polyester base fabric for an airbag according to any one of 1 to 6 above, which is coated with the following: 8. A polyester base fabric for airbags according to any one of 1 to 7 above, which is made of polyester fibers having a total fineness of 200 to 555 dtex and a single yarn fineness of 6.0 dtex or less. 9. The polyester base fabric for airbags according to any one of 1 to 8 above, which has a dry heat shrinkage rate of 3% or less. 10. A polyester base fabric for airbags according to any one of 1 to 9 above, having a weft bending rate of 3% or less. 11. A polyester base fabric for airbags according to any one of 1 to 10 above, having a VOC content of 100 ppm or less. 12. Scrub test times of 400 or more after 408 hours of aging treatment at 70℃ and 95% RH12. The polyester base fabric for an airbag according to any one of 1 to 11 above, wherein [Effects of the Invention]

[0008] According to the present invention, even if a base fabric is made of relatively inexpensive polyester fiber, when used in an airbag, it has various properties for protecting automobile occupants at a high level. It is possible to provide a base fabric. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 10 is a diagram for explaining a method for measuring the weft bending rate. DETAILED DESCRIPTION OF THE INVENTION

[0010] The technical concept of the present invention consists mainly of three elements: a scrub test run of 400 or more times after aging at 70°C and 95% RH for 408 hours, an energy allowance (EA) per unit weight calculated from the hysteresis energy of the base fabric at a stress of 120 N / cm of 5.0 J / g or less, and a restraint capacity utilization rate (RR) calculated from the ratio of the elongation at 120 N / cm to the elongation at break of 85% or more.

[0011] The present inventors conducted a detailed analysis of polyester fabrics and polyamide fabrics such as nylon 6,6. They found that even polyester fabrics can produce airbag fabrics comparable to polyamide fabrics if the number of scrub tests after 408 hours of aging treatment at 70°C and 95% RH is 400 or more. A more preferred number of scrub tests after 408 hours of aging treatment at 70°C and 95% RH is 450 or more. There is no particular upper limit to the number of scrub tests, but it is preferably 2500 or less, more preferably 2000 or less, depending on the relationship between the airbag fabric and the coating agent used.

[0012] According to the analysis by the inventors, ordinary polyester base fabrics tend to have inferior crumple resistance after wet heat degradation compared to polyamide base fabrics. This is thought to be because the bond between the silicone coating commonly used in airbag coatings and polyester is more susceptible to moisture than nylon 6,6.

[0013] There are no particular limitations on the means for obtaining a polyester base fabric that can withstand 400 or more scrub tests after 408 hours of deterioration treatment at 70°C and 95% RH, and for example, the surface of the polyester fiber may be modified.

[0014] However, to effectively utilize the low cost advantage of polyester fibers, it is recommended to increase the crimp rate of the polyester fibers constituting the base fabric, as described below. The inventors have discovered that the higher the crimp rate, the more irregularities there are in the surface structure of the base fabric, which increases the surface area in contact with the polyester base fabric and, as a result, improves the crumpling resistance after moist heat degradation. This eliminates the need for surface modification of the polyester fibers, making it possible to obtain a polyester base fabric for airbags that can withstand moist heat degradation at low cost.

[0015] In the present invention, the number of scrub tests for a base fabric after 408 hours of aging treatment at 70°C and 95% RH is measured according to ISO 5981. Specifically, a test piece after 408 hours of aging treatment at 70°C and 95% RH using a thermo-hygrostat is fixed to a scrub tester, and the test is performed under an initial load of 1 kgf, and the degree of peeling of the coating on the sample after the test is visually confirmed.

[0016] The polyester base fabric for airbags of the present invention preferably has an energy allowance (EA) per unit weight calculated by the following formula 1 of 5.0 (J / g) or less. Equation 1: EA(J / g)=(EW+EF) / W where EW( J / m 2) is the hysteresis energy per unit surface area in the warp direction when stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm. EF( J / m 2 ) is the hysteresis energy per unit surface area in the weft direction when stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm. W (g / m 2 ) is the weight of the base fabric per unit area, Each is shown.

[0017] Here, the value "120 N / cm" corresponds to the maximum stress applied to the airbag fabric during deployment. In other words, the energy tolerance when the airbag is stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm indicates the degree to which the airbag fabric can tolerate the energy it receives from the inflator during the airbag's deployment behavior. The smaller this energy tolerance, the better the deployment performance, and it is an important factor from the viewpoint of suppressing airbag burst due to the energy received by the fabric.

[0018] If the energy allowance (EA) per unit weight is 5.0 J / g or less, the resulting airbag can use the energy emitted from the inflator during deployment without waste, allowing for rapid deployment, and since the energy allowance of the base fabric is low, it is thought that the risk of bursting due to breakage of the base fabric can be reduced. A more preferable energy allowance (EA) per unit weight is 4.0 J / g or less. On the other hand, there is no particular lower limit for the energy allowance (EA) per unit weight, but considering the characteristics of polyester fibers, it is preferably 0.1 J / g or more, and more preferably 0.5 J / g or more.

[0019] The polyester base fabric for airbags of the present invention preferably has a restraining capacity utilization rate (RR) calculated by the following formula 2 of 85% or more. Equation 2: RR(%) = RW / BW + RF / BF where RW (mm) is the stretch of the base fabric in the warp direction when loaded with 120N / cm. BW (mm) is the elongation of the base fabric at break in the warp direction. RF (mm) is the elongation of the base fabric in the weft direction when loaded with 120N / cm. BF (mm) is the elongation of the base fabric at break in the weft direction. Each is shown. A more preferable restraining capacity utilization rate (RR) is 90% or more. On the other hand, there is no particular upper limit to the restraining capacity utilization rate (RR), but in view of the characteristics of the base fabric, it is preferably 200% or less, and even more preferably 150% or less.

[0020] The present inventors have found that polyester fabrics tend to burst more easily than polyamide fabrics. This is because conventional polyester fabrics are stiffer than polyamide fabrics such as nylon 6,6, and the stress-elongation curve of polyester fabrics reaches high stress with a shorter elongation than nylon 6,6, i.e., they are more rigid. Therefore, their elongation performance is inferior to that of nylon 6,6, and they cannot tolerate the energy generated during deployment, making them more likely to burst.

[0021] The restraint capacity utilization rate (RR), defined as the "elongation at 120 N / cm relative to the breaking elongation," indicates the slope of the stress-elongation curve in the airbag's deployment behavior. In other words, the inventors have discovered that the higher the restraint capacity utilization rate (RR), the greater the elongation of the base fabric during deployment, thereby reducing the risk of the airbag bursting during deployment due to sudden elongation of the base fabric.

[0022] In order to ensure safety during deployment, the initial number of scrub tests for the polyester airbag fabric of the present invention is preferably 500 or more, more preferably 550 or more. There is no particular upper limit to the number of scrub tests, but in consideration of the relationship between the polyester fabric and the coating agent used, it is preferably 3000 or less, more preferably 2500 or less.

[0023] In the present invention, the initial number of scrub tests for a base fabric is measured according to ISO 5981. Specifically, a test piece is fixed to a scrub tester, and the test is performed under an initial load of 1 kgf, and the degree of peeling of the coating on the sample after the test is visually confirmed.

[0024] Considering the restraint capacity utilization rate (RR) and the number of scrub tests, the cover factor (CF) of the polyester base fabric for airbags of the present invention is preferably 1900 to 2600. A more preferable lower limit of the cover factor (CF) is 2200, and a more preferable upper limit of the cover factor (CF) is 2500. The CF was calculated using the following formula. CF=(√A)×(W1)+(√B)×(W2) In the formula, A and B represent the thickness (dtex) of the warp and weft, respectively, and W1 and W2 represent the warp density and weft density (counts / 2.54 cm), respectively.

[0025] The polyester base fabric for airbags of the present invention has a basis weight of 300 g / m 2 It is preferably 233 g / m or less. 2 Within this range, the airbag base fabric can be easily made lighter, and further, the ease of storage in the module can be improved.

[0026] The lower limit of the basis weight of the polyester base fabric for airbags of the present invention is not particularly limited as long as it is within a range that ensures satisfactory breathability during use of the airbag. 2 If the thickness is above this, it is considered that the airbag has sufficient breathability to be used as an airbag.

[0027] In the present invention, the basis weight is measured in accordance with JIS L 1096 8.3. Two test pieces of approximately 200 mm x 200 mm are taken from the sample, and the bone dry mass (g) of each is measured. 2 Mass per unit (g / m 2 ) and calculate the average value to be the basis weight.

[0028] In the polyester base fabric for airbags of the present invention, the resin used is a silicone resin, and the resin content is 5 g / m 2 More than 50g / m 2 It is preferable that the silicone resin is applied in the range described above. Silicone resin is relatively inexpensive and can ensure excellent low air permeability. Furthermore, as long as the amount of resin applied is within the range described above, flexibility and storability can be ensured while sufficiently suppressing air permeability.

[0029] The polyester airbag fabric of the present invention is preferably composed of polyester fibers with a total fineness of 200 to 555 dtex. Polyester fibers tend to have higher rigidity than nylon 6,6 fibers, resulting in reduced packability. However, if the total fineness is 200 dtex or more, there is no need to increase the weave density excessively, which prevents an excessive increase in the binding force between the warp and weft yarns and helps to keep packability in the airbag module within an appropriate range. Furthermore, if the total fineness is 555 dtex or less, it is easier to prevent an excessive increase in the rigidity of the woven yarns themselves.

[0030] The polyester base fabric for airbags of the present invention is preferably composed of polyester fibers having a single yarn fineness of 6.0 dtex or less. If the single yarn fineness is 6.0 dtex or less, spinning operability and storability of the airbag can be ensured.

[0031] The polyester airbag fabric of the present invention preferably has a dry heat shrinkage of 3% or less, more preferably 2.5% or less, when dried for 30 minutes at 150° C. A dry heat shrinkage within this range sufficiently removes residual shrinkage of the yarn, and suppresses dimensional changes after completion of the airbag module.

[0032] The polyester base fabric for airbags of the present invention preferably has a weft bending rate of 3% or less, more preferably 2.5%. A weft bending rate within this range minimizes distortion of the woven fabric, which contributes to improving work efficiency in the cutting and sewing processes.

[0033] The airbag fabric of the present invention preferably has a VOC content of 100 ppm or less. If the VOC content is 100 ppm or less, it can comply with environmental regulations in each country.

[0034] In the polyester airbag fabric of the present invention, the crimp ratio of the yarns constituting the fabric is preferably 1.0% to 12.0% for both the warp and weft. More preferably, it is 1.5% to 10.0%, and even more preferably 2.0% to 7.0% for both the warp and weft. The inventors have discovered that within this range, a polyester fabric can be inexpensively obtained that satisfies the above-mentioned ranges for the number of scrub tests after 408 hours of aging treatment at 70°C and 95% RH, the energy allowance (EA) per unit weight, and the restraining capacity utilization rate (RR). That is, a crimp ratio within this range provides the fabric with appropriate irregularities, which not only improves adhesion between the polyester fabric layer and the resin layer and allows for uniform resin application, but also imparts appropriate stress-elongation characteristics and stress responsiveness to the fabric, making it easier to obtain a polyester fabric that satisfies the ranges for the energy allowance (EA) per unit weight and the restraining capacity utilization rate (RR).

[0035] When the crimp rate is within the above range, when the base fabric is pulled in the warp and weft directions during airbag deployment, the crimp stretches, acting like a cushion to absorb the sudden force applied to the base fabric, dispersing the stress. It is believed that this makes it possible to compensate for the drawback of polyester base fabric, which is said to be less stretchable than nylon base fabric.

[0036] The crimp rate in the present invention was measured by the method described in JIS L1096 (2010) 8.7.2 Method B. The load used was 1 / 10 g per 1 dtex.

[0037] Examples of polyester fibers used in the polyester base fabric for airbags of the present invention include polyethylene terephthalate and polybutylene terephthalate, and may also be fibers made of copolymerized polyesters in which polyethylene terephthalate or polybutylene terephthalate is copolymerized with an aliphatic dicarboxylic acid such as isophthalic acid, 5-sodium sulfoisophthalic acid, or adipic acid as an acid component.

[0038] The polyester base fabric for airbags of the present invention preferably has a weave density of 40 threads / 2.54 cm or more in both the warp and weft directions, more preferably 46 threads / 2.54 cm or more. A weave density of 46 threads / 2.54 cm or more can prevent the base fabric structure from collapsing during weaving. There is no particular upper limit to the weave density, but due to restrictions on weft insertion during weaving, it is preferably 70 threads / 2.54 cm or less.

[0039] In the present invention, the weave density is measured according to JIS L1096 (2010) 8.6.1. Specifically, the sample is placed on a flat table, and unnatural wrinkles and tension are removed. Then, the number of warp and weft threads in 2.54 cm sections is counted at five different locations, and the average value for each unit length is calculated to determine the weave density.

[0040] The tensile strength of the polyester airbag fabric of the present invention is preferably 500 N / cm or more, more preferably 550 N / cm or more, from the viewpoint of mechanical properties. There is no particular upper limit to the tensile strength, but in view of the relationship between the total fineness and tensile strength of the polyester multifilaments used and the weave density of the airbag fabric, it is preferably 1000 N / cm or less, more preferably 900 N / cm or less.

[0041] In the present invention, the tensile strength of the base fabric is measured according to JIS L1096 (2010) 8.12.1. Specifically, a test piece is gripped with a tensile tester under an initial load, and the test is performed under the conditions of a test piece width of 50 mm, grip spacing of 200 mm, and a pulling speed of 200 m / min, and the strength at break (N) is measured. However, specimens that break within 10 mm from the grip or abnormal breaks are excluded.

[0042] The aspect ratio of the cross-sectional shape of the single yarn of the polyester fiber constituting the polyester airbag fabric of the present invention is preferably 1.4 or less. The cross-sectional shape of the single yarn constituting the airbag fabric may change to a shape different from the cross-sectional shape of the single yarn of the raw yarn due to the influence of tension during processing, etc. When the cross-sectional shape of the single yarn constituting the airbag fabric has an aspect ratio of 1.4 or less, the cross sections of the yarns are neatly aligned in a predetermined direction when the airbag is folded, making it easier to achieve the desired low breathability.

[0043] The dry heat shrinkage of the polyester fiber used as the raw yarn for producing the polyester airbag fabric of the present invention is preferably 3% or more, more preferably 4% or more, from the viewpoints of reducing breathability and imparting a moderate crimp rate. On the other hand, if the dry heat shrinkage rate is too high, the thickness of the airbag fabric after shrinkage processing may increase, or the surface may become too uneven, making it difficult to form a uniform resin layer. Furthermore, from the viewpoint of fitability in a module, the dry heat shrinkage rate of the polyester fiber used as the raw yarn is preferably 12% or less, more preferably 10% or less. By setting the dry heat shrinkage rate within the above range, a coated airbag fabric with low breathability, a moderate crimp rate, and good fitability in a module can be obtained by the subsequent shrinkage treatment.

[0044] In the present invention, the dry heat shrinkage of raw yarn is measured according to JIS L1013 (2010) 8.18.2, dry heat dimensional change rate, method B. Specifically, the measurement is performed as follows: An initial load is applied to the sample, two points 500 mm apart are marked, the initial load is then removed, and the sample is hung in a dryer at 180°C and left for 30 minutes. The sample is then removed and cooled to room temperature, after which the initial load is applied again. The length between the two points is measured, and the dry heat dimensional change rate (%) is calculated using the following formula, and the average of three measurements is taken as the dry heat shrinkage rate. ΔL=L-500 / 500×100 ΔL: Dry heat shrinkage rate (%) L: Length between two points (mm)

[0045] Hereinafter, manufacturing methods suitable for obtaining the polyester airbag fabric of the present invention will be described in detail, but the polyester airbag fabric of the present invention is not limited to fabrics manufactured by these manufacturing methods.

[0046] The warp tension when weaving the polyester airbag fabric of the present invention is preferably 120 to 200 cN / thread. If the warp tension is 120 cN / thread or more, slack in the warp threads during weaving is unlikely to occur, which would lead to fabric defects or loom stoppages, and the crimp rate can be controlled within an appropriate range. On the other hand, if the warp tension is 200 cN / thread or less, it is easy to avoid excessive load being applied to the warp threads, which would lead to fabric defects.

[0047] Since it is more difficult to increase the crimp rate of polyester fiber than nylon 6,6 fiber, when weaving the polyester airbag fabric of the present invention, it is preferable to set the reed dwell angle to 60 to 120° in order to increase the crimp rate while suppressing defects in the fabric. If the reed dwell angle is outside this angle range, it may be difficult to ensure a sufficient flight area for the weft yarn, which may result in frequent defects in the fabric.

[0048] Furthermore, in order to improve the crimp rate in the warp direction and also to suppress defects in the base fabric, it is preferable to install a guide roll between the back roller and the heddles so that the warp yarns are raised 20 to 50 mm from the warp line. If the warp line is out of this position range, there is a concern that defects in the base fabric will occur frequently due to the difference in tension between the upper thread and the lower thread.

[0049] In addition, it is preferable to attach a positive easing mechanism to the back roller to improve the crimp rate in the warp direction while maintaining the strength of the base fabric. The easing amount in the positive easing mechanism is preferably 5 to 7.5 mm, and the easing timing is preferably ±30° of the cross timing of the loom. Using the positive easing mechanism within this setting range prevents excessive tension from being applied to the warp yarns during shedding, preventing excessive load from being applied to the yarns and maintaining the strength of the base fabric. Furthermore, since the warp yarns can be shed with the appropriate tension, the crimp rate in the warp direction can be improved. Furthermore, adjusting the pump diameter, stroke, and nozzle diameter to increase the yarn conveying force is preferable to improve the crimp rate in the warp direction.

[0050] Since it is more difficult to increase the crimp rate of polyester fibers than nylon 6,6 fibers, it is preferable to set the winding tension of the winder in the weaving process to 250 to 1500 N. Since polyester base fabrics are more rigid than nylon 6,6 base fabrics and the winding tension can be set lower than that of nylon 6,6, the crimp rate can be improved by setting the winding tension low enough to prevent wrinkles and slack during winding.

[0051] Examples of shrinking processes include hot water processing and heat setting processes typified by pin tentering, but hot water processing using hot water for shrinking is particularly preferred. When using hot water, methods such as immersing the woven fabric obtained by the weaving process in hot water or spraying hot water onto the woven fabric can be used. The temperature of the hot water is preferably about 80 to 100°C, more preferably 95°C or higher. This temperature of hot water is preferred because it allows the greige fabric after weaving to shrink efficiently and improves the crimp rate of the base fabric. The woven fabric obtained by weaving may be dried and then shrunk, but from the perspective of production costs, it is advantageous to shrink the woven fabric obtained by weaving without drying it and then dry-finish it.

[0052] The drying temperature for the hot air drying process in the manufacturing process of the polyester airbag fabric of the present invention is preferably such that the surface temperature of the fabric at the dryer outlet is 100°C to 150°C. If the surface temperature of the fabric is within this range, the fabric can be sufficiently dried, and the hot air can also improve the crimp rate of the fabric. Furthermore, the temperature of the hot air dryer is preferably adjusted so that the surface temperature of the fabric at the dryer outlet is in the range of 100°C to 150°C, and therefore the temperature of the hot air dryer is preferably set to 130°C to 180°C.

[0053] The coating resin used in the coating step in the manufacturing process of the polyester airbag fabric of the present invention is preferably an elastomer resin having heat resistance, cold resistance, and flame retardancy, but silicone-based resins are the most effective. Specific examples of silicone-based resins include addition polymerization type silicone rubbers. Examples include dimethyl silicone rubber, methyl vinyl silicone rubber, methyl phenyl silicone rubber, trimethyl silicone rubber, fluorosilicone rubber, methyl silicone resin, methyl phenyl silicone resin, methyl vinyl silicone resin, epoxy-modified silicone resin, acrylic-modified silicone resin, and polyester-modified silicone resin. Among these, methyl vinyl silicone rubber is preferred because it has rubber elasticity after curing, has excellent strength and elongation, and is cost-effective.

[0054] The viscosity of the silicone resin used in the polyester airbag fabric of the present invention is extremely important. The viscosity of the silicone resin is preferably 10 Pa·sec or higher, more preferably 15 Pa·sec or higher. While there is no upper limit, if the viscosity exceeds 40 Pa·sec, the resin cannot be present in the mesh between the warp and weft yarns on the uncoated surface, which is essential for improving the tensile strength of the coated polyester fabric. As long as the viscosity can be adjusted within the above range, either a solvent-based or solventless system is acceptable. However, considering the environmental impact, a solventless system is preferred. In the present invention, in the case of a resin composition containing additives other than resin, the viscosity of the resin composition is also defined as "resin viscosity."

[0055] Furthermore, it is preferable that the resin have a film strength of 3 MPa or more and a film elongation of 250% or more. Generally, film strength and film elongation are linked physical properties. However, when the resin is present in the mesh area between the warp and weft yarns, the resin elongates, improving the conformability of the coated fabric during scrub tests and achieving high knead resistance. A more preferable range for film elongation is 300% or more. While there is no particular upper limit for film strength, 10 MPa or less is preferred. Samples for measuring the film strength and elongation of silicone resin are prepared according to the conditions (temperature, time, and pressure) used to coat and form the film on an actual airbag fabric. Specifically, a silicone resin film with a constant thickness of 0.5 mm is prepared, cured at 190°C for 2 minutes using a hot air irradiation method, and then subjected to a tensile test.

[0056] The hardness of the resin is measured in accordance with ASTM D2240 using a Shore A hardness tester, and is preferably 40 or less. More preferably, it is 38 or less. When the hardness is 40 or less, the resin has good conformability due to deformation during a scrub test, similar to the resin elongation, and the base fabric can achieve high knead resistance. The lower limit is not particularly limited, but is usually 25 or more.

[0057] The polyester base fabric for airbags of the present invention preferably has a warp-to-weft average resin thickness at the top of the coated fabric surface of 4 μm or more, more preferably 6 μm or more. The top refers to the portion of the warp or weft where the resin film thickness is thinnest. In the present invention, it is preferable that the resin not penetrate too deeply into the fabric, but be present in a relatively uniform film thickness throughout the coated fabric, particularly at the top of the fabric. If the resin thickness is less than 4 μm, the breathability and flame retardancy may not be satisfied. There is no specific upper limit, but if it is 25 μm or more, application by knife coating becomes difficult.

[0058] The polyester base fabric for airbags of the present invention preferably has a warp-to-weft average resin thickness at the top of the coated fabric surface of 4 μm or more, more preferably 6 μm or more. The top refers to the portion of the warp or weft where the resin film thickness is thinnest. In the present invention, it is preferable that the resin not penetrate too deeply into the fabric, but be present in a relatively uniform film thickness throughout the coated fabric, particularly at the top of the fabric. If the resin thickness is less than 4 μm, the breathability and flame retardancy may not be satisfied. There is no specific upper limit, but if it is 25 μm or more, application by knife coating becomes difficult.

[0059] In the present invention, conventionally known methods can be used to apply the resin, but knife coating, particularly knife-on-air coating, is most preferred in terms of ease of adjusting the coating amount and the impact of foreign matter (protrusions) being mixed in. With the knife-on-bed method, the resin can easily penetrate deep into the fabric, but it becomes difficult for the resin to be present on the top of the fabric on the coated surface, making it impossible to achieve the breathability reduction that is originally required of coated fabrics. In the present invention, the knife used for knife coating can have a semicircular, angular, or other blade tip shape.

[0060] In knife coating using the knife-on-air method, the tension of the base fabric in the direction of travel is preferably 500 to 2000 N / m, and particularly preferably 1000 to 1800 N / m. If the tension of the base fabric in the direction of travel is less than 500 N / m, the selvage of the base fabric becomes bulky, which tends to result in a large difference in the amount of coating between the center and edges of the base fabric. On the other hand, if the tension of the base fabric in the direction of travel exceeds 2000 N / m, the gaps between the warp and weft yarns are filled, preventing the resin from being present in the mesh between the warp and weft yarns on the uncoated side. In addition, the base fabric is stretched during coating, which may reduce the crimp rate of the base fabric.

[0061] In the present invention, it is important that the knife depression amount is 1 to 6 mm. In the knife-on-air method, the height of the top surface of the bed immediately preceding the knife is set to 0 mm, and the knife depression amount corresponds to the distance the knife is depressed downward from that height. It is more preferably 1.5 to 4.5 mm. If the knife depression amount is less than 1 mm, the resin cannot be present in the mesh between the warp and weft yarns on the uncoated side, which is the objective of the present invention. If it is 6 mm or more, the resin can easily penetrate into the interior of the fabric, but it becomes difficult for the resin to be present at the top of the fabric on the coated side, and the breathability inhibition originally required for coated fabrics cannot be achieved.

[0062] Common heating methods such as hot air, infrared light, and microwaves can be used to dry and cure the coating agent after application. Regarding the coating curing temperature and curing time, it is preferable that the surface temperature of the base fabric at the exit of the heat treatment machine is 165°C to 200°C. If the surface temperature of the base fabric is within this range, not only will the silicone resin be sufficiently cured, but the heat can also improve the crimp rate of the base fabric. Furthermore, it is preferable that the temperature of the heat treatment machine be set to a range of 165°C to 200°C at the exit of the heat treatment machine, and therefore it is preferable to set the temperature of the heat treatment machine to 200°C to 220°C.

[0063] Airbags using the polyester airbag fabric of the present invention are suitable for use in, for example, driver's seat airbags, passenger seat airbags, curtain airbags, side airbags, knee airbags, seat airbags, reinforcing fabrics, etc. Therefore, these products are also included in the scope of the present invention. As airbags using the airbag fabric of the present invention, airbags that require particularly long components in the weft direction are preferred because the coated airbag fabric of the present invention is less likely to cause misalignment after sewing when cutting components that are long in the weft direction. Specifically, side curtain airbags are preferred. Furthermore, since the coated airbag fabric of the present invention is particularly excellent in storage capacity, airbags that particularly require storage capacity are also preferred. Specifically, driver's seat airbags, passenger seat airbags, and curtain airbags are preferred. As airbags using the airbag fabric of the present invention, airbags that require long components in the weft direction and storage capacity are more preferred. Specifically, side curtain airbags are more preferred. [Example]

[0064] The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to the following examples, and it is of course possible to carry out the present invention with appropriate modifications within the scope of the above and below-mentioned aims, and all such modifications are included within the technical scope of the present invention. The test methods for various properties used in the following examples are as follows.

[0065] <Base fabric weight> Measurements were made in accordance with JIS L1096 (2010) 8.3.2. Two test pieces measuring approximately 200 mm x 200 mm were taken from the sample, and the bone dry mass (g) of each was measured to determine the mass per 1 m2 (g / m2), and the average value was calculated to obtain the basis weight.

[0066] <Weave density of base fabric> Measurements were made based on JIS L1096 (2010) 8.6.1. The sample was placed on a flat table, and after removing any unnatural wrinkles or tension, the number of warp and weft threads in 2.54 cm sections was counted at five different locations, and the average value for each unit length was calculated to determine the density.

[0067] <Base fabric thickness> Measurements were made in accordance with JIS L1096 (2010) 8.4. Specifically, measurements were taken at five different points on the sample using a thickness gauge under a pressure of 23.5 kPa, after waiting 10 seconds for the thickness to settle, and the average value was calculated.

[0068] <Tensile strength and elongation at break of base fabric> Measurements were made based on JIS K 6404-3:1999 6. Test Method B (Strip Method). The test piece was gripped by a tensile testing machine under an initial load, and the test was carried out under the conditions of a test piece width of 50 mm, grip spacing of 200 mm, and a tensile speed of 200 m / min, and the strength (N) and elongation (mm) at break were measured. However, specimens that broke within 10 mm from the grip or abnormally broken specimens were excluded.

[0069] <Energy allowance per unit weight> The energy tolerance per unit weight was determined based on JIS K 6404-3:1999 6. Test Method B (Strip Method). Three 30mm wide and 300mm long test pieces were prepared in each of the warp and weft directions by removing the yarns from both sides of the width. These were stretched in a constant-speed tension tester at a grip distance of 150mm and a tensile speed of 200mm / min until the stress reached 120N / cm. Immediately after this, the test piece was relaxed at a tensile speed of 200mm / min until the stress reached 0N / cm. The area enclosed by the curve from the start to the end of stretching was calculated based on the obtained stress and elongation data and the following equation (3). This area corresponds to the amount of energy the base fabric can tolerate during the stretching process. Based on the results of integrating the calculated areas, the average values ​​in the warp and weft directions of the base fabric were calculated, and then these average values ​​were divided by the surface area of ​​the base fabric between the chucks (30mm x 150mm) to calculate the hysteresis energy per unit surface area.The hysteresis energy per surface area between the chucks of the base fabric in the warp and weft directions was divided by the basis weight of the fabric to calculate the energy allowance in the warp direction (EW) and the energy allowance in the weft direction (EF). Energy absorption at any point in time = {(n+1th elongation) - (nth elongation)} × (n+1th stress) (3) Here, the nth elongation refers to the warp or weft elongation value at any point in the series of processes from applying stress in the warp or weft direction to subsequent relaxation, and the n+1th elongation (stress) refers to the warp or weft elongation (stress) value 50 msec after the nth elongation (stress). Formula (3) calculates the energy allowance at any point in the series of processes from applying stress in the warp or weft direction to relaxation. Therefore, the energy allowances obtained at each point from start to finish are added together and the total is divided by the surface area between the chucks (30 mm × 150 mm) to calculate the hysteresis energy per unit surface area. Furthermore, the energy allowance in the warp direction (EW) and the energy allowance in the weft direction (EF) can be calculated by dividing the hysteresis energy per surface area between the chucks in the warp and weft directions by the basis weight.

[0070] <Restraint ability usage rate> The restraint capacity utilization rate was determined based on JIS K 6404-3:1999 6. Test method B (strip method), with the yarns removed from both sides of the width in each of the warp and weft directions to obtain three test pieces, each 30 mm wide and 300 mm long. These were then stretched in a constant-speed tension testing machine with a gripping distance of 150 mm and a pulling speed of 200 mm / min until the stress reached 120 N / cm, and the restraint capacity utilization rate in the warp direction (RW) and the restraint capacity utilization rate in the weft direction (RF) were calculated based on the obtained elongation data, the above-specified elongation at break of the base fabric, and the following formula (4). Elongation at 120 N / cm / Elongation at break (4)

[0071] <Number of initial scrub tests on base fabric> The calculation was based on ISO 5981. Specifically, five test pieces were taken from the sample, each test piece was fixed to a scrub tester, and the test was performed under an initial load of 1 kgf. After the test, the degree of peeling of the sample's coating was visually confirmed. The number of times just before the sample's coating peeled off and the base fabric surface was exposed, i.e., the limit number of times the sample's coating did not peel off, was determined in increments of 50, and the average value was calculated to be the number of scrubs tested.

[0072] <Number of scrub tests on base fabric after 408 hours of aging at 70℃ and 95% RH> The sample was subjected to aging treatment at 70°C and 95% RH for 408 hours using a low-temperature constant temperature and humidity chamber PL-2J manufactured by ESPEC Corporation, and the scrub test was performed using the aged sample in accordance with ISO 5981. Specifically, five test pieces were taken from the sample, and each test piece was fixed to a scrub tester and subjected to a test under an initial load of 1 kgf. After the test, the degree of peeling of the coating on the sample was visually confirmed. The number of times just before the sample coating peeled off and the base fabric surface was exposed, i.e., the limit number of times the sample coating did not peel off, was determined in increments of 50, and the average value was calculated to be the number of scrub tests.

[0073] <Dry heat shrinkage rate of base fabric> Measurements were performed in accordance with JIS L1096 (2010) 8.38.3. Specifically, two test pieces measuring approximately 250 mm x 250 mm were taken from the sample, and three marks were made at equal intervals in the vertical and horizontal directions over a 20 cm length, starting 2.5 cm from the cut edge. The length between the marks was recorded as the pre-treatment length. The samples with the recorded lengths were dried in a constant-temperature oven at 150°C for 30 minutes, and the post-treatment samples were removed. The length between the marks was recorded as the post-treatment length, as in the pre-treatment period, and the dry heat shrinkage was calculated using the following formula (5). Dry heat shrinkage rate (%)=(b―a) / a × 100 ···(5) a: Length before treatment (cm), b: Length after treatment (cm)

[0074] <Base fabric grain bending rate> Measurements were made in accordance with JIS L1096 (2010) 8.12.A. Specifically, one test piece measuring 10cm in length across the entire width was taken from the sample, and a weft line AB was drawn from one edge A along the weft yarn to the other edge B as shown in Figure 1. Next, a line was drawn from A perpendicular to the edge, and the point where it intersects with the other edge was designated C. The length a (cm) of line AC (width) was found, and the maximum skew distance (cm) between AC shown in Figure 1 was measured, and the weft bending rate was calculated using the following formula (6). Weft curl (%) = b / a × 100 (6) a: Width (cm), b: Maximum diagonal distance (cm)

[0075] <VOC content of base fabric> Measurements were made in accordance with VDA278. Specifically, 30 mg ± 5 mg of sample was precisely weighed, and the sample was heated at 90°C for 30 minutes. The components generated were measured using thermal desorption-GCMS and quantified in toluene equivalents. The same measurement was performed twice, and the higher value was taken as the VOC content.

[0076] <Crimping rate of base fabric> Measurement was performed according to the method described in JIS L1096 (2010) 8.7.2 Method B. The load used was 1 / 10 g per 1 dtex.

[0077] <Amount of coating applied to base fabric> After the resin was cured, a 5 cm square piece of the coated fabric was taken and immersed in a solvent that dissolves only the base fabric fiber (hexafluoroisopropanol in the case of polyester fiber) to dissolve the base fabric. Next, only the insoluble silicone coating layer was collected and washed with acetone. After vacuum drying, the sample was weighed. The coating amount was 1 m 2 Mass per unit (g / m 2 ) is expressed as

[0078] <Total fineness of raw yarn> Measurement was performed in accordance with JIS L1013 (2010) 8.3.1. Specifically, an initial load was applied to a sample exactly 90 cm long, and its bone dry mass was measured. The corrected fineness (dtex) was calculated based on the following formula (7), and the average value of five measurements was taken as the total fineness. F0=1000×m / 0.9×+(100+R0) / 100 ···(7) F0: normal fineness (dtex), L: length of sample (m), m: bone dry mass of sample (g), R0: official moisture content (%)

[0079] (Example 1) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 555 dtex / 96f were used for the warp and weft, and the set weave density for both warp and weft was 51 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 98°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 120°C. Next, a solventless silicone resin composition with a resin viscosity of 18 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 26 g / m 2 The coating conditions were adjusted to the conditions shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 170°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0080] (Example 2) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 470 dtex / 144f were used for the warp and weft, and the set weave density for both warp and weft was 51 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 98°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 120°C. Next, a solventless silicone resin composition with a resin viscosity of 18 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 24 g / m 2The coating conditions were adjusted to the conditions shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 170°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0081] (Example 3) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 470 dtex / 96f were used for the warp and weft, and the set weave density for both warp and weft was 46 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 98°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 120°C. Next, a solventless silicone resin composition with a resin viscosity of 18 Pa·sec was applied to one side of the fabric using a knife-on-air method at a rate of 15 g / m 2 The coating conditions were adjusted to the conditions shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 170°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0082] (Example 4) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 470 dtex / 96f were used for the warp and weft, and the set weave density for both warp and weft was 46 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 98°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 120°C. Next, a solventless silicone resin composition with a resin viscosity of 50 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 15 g / m 2The coating conditions were adjusted to the conditions shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 170°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0083] (Example 5) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 470 dtex / 144f were used for the warp and weft, and the set weave density for both warp and weft was 58.5 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 98°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 120°C. Next, a solventless silicone resin composition with a resin viscosity of 18 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 25 g / m 2 The coating conditions were adjusted to the conditions shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 170°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0084] (Example 6) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 555 dtex / 144f were used for the warp and weft, and the set weave density for both warp and weft was 54.5 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 98°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 120°C. Next, a solventless silicone resin composition with a resin viscosity of 18 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 25 g / m 2The coating conditions were adjusted to the conditions shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 170°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0085] (Comparative Example 1) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 560 dtex / 96f were used for the warp and weft, and the set weave density for both warp and weft was 46 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 65°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 90°C. Next, a solventless silicone resin composition with a resin viscosity of 50 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 29 g / m 2 The coating conditions were adjusted to those shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 160°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0086] (Comparative Example 2) Polyester multifilament yarns (single yarn cross section is round) with a fineness of 560 dtex / 96f were used for the warp and weft, and the set weave density for both warp and weft was 46 threads / 2.54 cm. The weaving conditions were as shown in Table 1. The fabric was woven in a plain weave using a water jet loom, and then passed through a hot water shrinkage bath at 65°C without drying. Subsequently, the fabric was passed through a drying process so that the surface temperature of the base fabric at the dryer outlet (measured with a non-contact thermometer) was 90°C. Next, a solventless silicone resin composition with a resin viscosity of 50 Pa·sec was applied to one side of the fabric using a knife-on-air method at a coating amount of 18 g / m 2The coating conditions were adjusted to those shown in Table 1 so that the temperature of the fabric surface at the outlet of the heat treatment machine (measured with a non-contact thermometer) was 160°C, and a coated fabric was obtained. Details of the manufacturing conditions are shown in Table 1, and the physical properties of the obtained coated fabric are shown in Table 2.

[0087] [Table 1]

[0088] [Table 2] [Industrial Applicability]

[0089] The present invention provides a polyester base fabric for airbags that has high restraint performance for receiving an occupant when deployed while maintaining the mechanical properties of an airbag, and further maintains this performance at a high level even with aging. Therefore, it is possible to popularize relatively low-cost polyester airbags, which will greatly contribute to the development of the industry. [Explanation of symbols]

[0090] A: Point on one edge B: Other ear tip point C: Draw a line perpendicular to the edge from A and cross it with another edge. a: Length of line AC (width) b: Maximum diagonal distance between A and C

Claims

1. A polyester base fabric for airbags having a resin disposed on at least one surface, The crimp rate of the yarns constituting the polyester base fabric for airbags is 1.0% to 12.0% for both the warp and weft yarns, A polyester base fabric for airbags, characterized in that the energy allowance (EA) per unit weight calculated by the following formula 1 is 5.0 (J / g) or less: Formula 1: EA(J / g)=(EW+EF) / W where EW (J / m 2 ) is the hysteresis energy per unit surface area in the warp direction when stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm. EF (J / m 2 ) is the hysteresis energy per unit surface area in the weft direction when stretched to a stress of 120 N / cm and then relaxed to a stress of 0 N / cm. W (g / m 2 ) is the weight of the base fabric per unit area; Each is shown.

2. A polyester base fabric for airbags having a resin disposed on at least one surface, The crimp rate of the yarns constituting the polyester base fabric for airbags is 1.0% to 12.0% for both the warp and weft yarns, A polyester base fabric for airbags, characterized in that the restraint capacity utilization rate (RR) calculated by the following formula 2 is 85% or more: Formula 2: RR (%)=RW / BW+RF / BF where RW (mm) is the elongation of the base fabric in the warp direction under a load of 120 N / cm. BW (mm) is the elongation of the base fabric at break in the warp direction, RF (mm) is the elongation of the base fabric in the weft direction when loaded at 120 N / cm. BF (mm) is the elongation of the base fabric at break in the weft direction, Each is shown.

3. A polyester base fabric for airbags having a resin disposed on at least one surface, The crimp rate of the yarns constituting the polyester base fabric for airbags is 1.0% to 12.0% for both the warp and weft yarns, A polyester base fabric for airbags, characterized in that it can withstand a scrub test 400 times or more after aging treatment at 70°C and 95% RH for 408 hours.

4. The polyester base fabric for airbags according to any one of claims 1 to 3, which has an initial scrub test count of 500 or more.

5. The polyester base fabric for airbags according to any one of claims 1 to 4, wherein the cover factor is 1900 to 2600.

6. Weight per unit area: 300g / m ２ The polyester base fabric for airbags according to any one of claims 1 to 5, wherein:

7. The resin is a silicone resin, and the content is 5 g / m ２ 50g / m or more ２ The polyester base fabric for airbags according to any one of claims 1 to 6, wherein the following is applied:

8. The polyester base fabric for airbags according to any one of claims 1 to 7, which is composed of polyester fibers having a total fineness of 200 to 555 dtex and a single yarn fineness of 6.0 dtex or less.

9. The polyester base fabric for airbags according to any one of claims 1 to 8, which has a dry heat shrinkage rate of 3% or less.

10. The polyester base fabric for airbags according to any one of claims 1 to 9, wherein the weft bending rate is 3% or less.

11. The polyester base fabric for airbags according to any one of claims 1 to 10, wherein the VOC content is 100 ppm or less.

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