MULTI-LAYER FABRIC.

Abstract

This disclosure relates to a multi-layer fabric and an airbag formed by the multi-layer fabric. The multi-layer fabric can provide an airbag capable of adequately protecting a driver or passenger by minimizing injury from broken glass fragments when a vehicle rolls over.

Description

MULTI-LAYER FABRIC Field of invention Cross-reference to (related) application(s) This application claims the benefits of Korean patent applications No. 10-20190121187 filed on September 30, 2019 and No. 10-2020-0125231 filed on September 25, 2020 with the Korean Intellectual Property Office, the disclosure of which is incorporated herein by reference in its entirety. This disclosure refers to a multi-layered fabric. Background of the invention In recent years, there has been a demand for improved safety for drivers and passengers in traffic collisions, such as motor vehicle collisions, and as a result, airbags are being installed more frequently. An airbag sensor detects the impact a vehicle receives during a frontal or side collision, and the airbag deploys and inflates rapidly by introducing gas from an inflator into airtight bubbles. The airbag then protects the human body by reducing the impact on the driver or passenger with the shock-absorbing properties of the inflated bubbles. In the past, airbags were installed in the front of the vehicle, such as in the driver's seat or in the driver's and front passenger's seats, primarily to protect a passenger's face and upper body in a frontal collision. However, in recent years, curtain airbags have also been developed that can respond to a side collision or vehicle rollover. This curtain airbag is designed to be stored in the area between a front pillar and a rear pillar along a roof rail on the side wall of a vehicle, and to inflate and deploy along the side window in the event of a collision. The curtain airbag must have excellent storage capacity (it must fold compactly). Furthermore, since the distance between the passenger's head and the side window is short, it is necessary to momentarily press between the passenger's head and the glass to protect the head in a side collision; therefore, the curtain airbag must inflate and deploy quickly. Additionally, the airbag must maintain a certain internal pressure for several seconds after deployment in the event of a rollover.However, it is very rare for the side window not to break when the vehicle rolls over, and the airbag is easily ruptured by the broken side glass fragments, making it difficult to protect the passengers. Detailed description of the invention Technical problem This disclosure provides a multi-layered fabric capable of minimizing the damage caused Leoenn / zznz / E / YiAi for shards of broken glass. In this disclosure, an air bag formed by the multi-layered fabric is also provided. Technical Solution A multi-layer fabric and an air bag formed using the same, according to specific embodiments of the present invention, will now be described. According to one embodiment of this disclosure, a multi-layered fabric is provided that includes an inflatable portion; and a co-woven portion surrounding the inflatable portion, wherein at least one layer of the inflatable portion comprises a first region formed by two or more types of fabrics, including 1 / 1 taffeta. Multi-layer fabric is manufactured without a seam by a one-piece weaving method, and may be a one-piece woven fabric that includes an inflatable part having a structure of two or more separate layers and a jointly woven part surrounding the inflatable part. Multi-layered fabric can be inflated by its structure, which is why it's used in vehicle airbags and life vests. Specifically, the multi-layered fabric used in vehicle airbags must remain inflated to protect the driver or passenger in a rollover. However, a problem arises: the multi-layered fabric used for airbags can tear from broken glass fragments and, therefore, may not provide sufficient protection to the driver or passenger. It has been found that introducing a specific weaving pattern into multilayer fabric can minimize damage from broken glass fragments while maintaining superior properties of single-piece woven fabric, thus completing the present invention. The inflatable portion of the multi-layer fabric has a structure of two or more separate layers; for example, it may have a two-layer, three-layer, or four-layer structure. Furthermore, the layer that constitutes the inflatable portion is a fabric and may be referred to as the fabric layer in this disclosure. The inflatable part is enclosed by a woven part that surrounds it, so that when gas is supplied to the inflatable part, the supplied gas can be confined and the inflatable part can inflate. Multi-layer fabric is a one-piece woven fabric manufactured by a one-piece weaving method, and the jointly woven portion can refer to a group of woven stitches (jointly woven stitches) formed along the edge of the inflatable portion by crossing the yarn (warp or weft) of one fabric layer that constitutes the inflatable portion with the yarn (warp or weft) of another fabric layer. More specifically, the jointly woven portion can be a group of woven stitches formed along the edge of the inflatable portion by crossing the warp of one fabric layer that constitutes the inflatable portion with the weft of another fabric layer, or a group of woven stitches by crossing the warp and weft of one fabric layer that constitutes the inflatable portion with the warp and weft of another fabric layer, respectively.When the multi-layered fabric includes the inflatable part that has a structure of three or more separate layers, the threads of the two outermost fabric layers cross over to form woven stitches along the length. Lóornn / zznz / E / YiAi edge of the non-reliable part to close the inflatable part. Of course, a part to introduce a necessary configuration in the technique, such as an inlet to supply gas to the inflation part, can be manufactured in an unclosed state. In this disclosure, a double-layered fabric having a two-layer structure will be described in detail as the multi-layered fabric, but these contents may apply to a multi-layered fabric having a structure of three or more layers as is. Multilayer fabric, as shown in Figure 1, can be a double-layer fabric having a structure in which two separate fabric layers and the outer periphery of the two fabric layers are woven together by a jointly woven part. The multi-layer fabric according to the modality may include a first region in which at least one layer that constitutes the inflatable part is formed by two or more types of fabrics, including 1 / 1 taffeta. Fabrics woven with 1 / 1 plain weave tend to have high tensile strength but low tear strength because the yarns are densely packed. Tear strength in fabrics refers to the resistance to the force required to break the warp or weft yarns. When a force is applied to a single strand of yarn, the yarn breaks momentarily, but when the same force is applied to two or more yarns, the yarn is pushed by the force rather than breaking. This yarn movement occurs more frequently in other weaves than in 1 / 1 plain weave, which is why fabrics woven with weaves other than 1 / 1 plain weave can exhibit relatively high tear strength compared to fabrics woven with 1 / 1 plain weave.However, fabrics woven with weaves other than 1 / 1 taffeta have very low tensile strength compared to fabrics woven with 1 / 1 taffeta, and are therefore unsuitable for airbag fabrics. Accordingly, the multi-layer fabric according to the modality includes a first region in which at least one layer constituting the inflatable part is formed by two or more types of fabrics, including 1 / 1 taffeta, so that it is not easily broken by sharp objects such as fragments of broken glass and exhibits excellent mechanical properties such as tensile strength. In addition, the remaining area, excluding the first layer area that constitutes the inflatable part, may be composed of a second area made of 1 / 1 taffeta. As a result, the multi-layer fabric exhibits excellent tensile strength similar to that of 1 / 1 taffeta fabric and significantly improved tear resistance compared to 1 / 1 taffeta fabric, so that it can be properly used for curtain-type air bags stored in locations that are easily torn by glass fragments. In particular, in the first region, a non-1 / 1 taffeta fabric is inserted every 2 to 15 1 / 1 taffeta, so that the multi-layered fabric exhibits excellent tensile strength similar to that of 1 / 1 taffeta, and significantly improved tear strength compared to 1 / 1 taffeta. More specifically, the first region can be woven in a pattern in which a non-1 / 1 taffeta weave is inserted every 2 to 15, 2 to 13, 2 to 11, 3 to 15, 5 to 15, 3 to 13, 5 to 11, 2 to 5, 3 to 5, or approximately 5 1 / 1 taffeta. The multi-layered fabric, including the first region, can exhibit a Leoenn / zznz / E / YiAi significantly improved tear resistance compared to general OPW fabric made of only 1 / 1 taffeta, and the airbag made from this multi-layer fabric can show excellent airtightness even after deployment. Fabric that is not 1 / 1 taffeta may have each predetermined number of 1 / 1 taffeta threads described above inserted in the warp direction of the fabric layer, each predetermined number of 1 / 1 taffeta threads described above in the weft direction, or each predetermined number of 1 / 1 taffeta threads described above in both the warp and weft directions. Among them, it is advantageous to insert the non-taffeta 1 / 1 fabric at each predetermined number of 1 / 1 taffeta described above in both the warp and weft directions of the fabric layer, as it is possible to further improve tear resistance while maintaining excellent durability of the multi-layered fabric. At 5.1 to 3.1 to 2 or 1, fabric that is not 1 / 1 taffeta can be inserted, each predetermined number of 1 / 1 taffeta described above. Within this range, it is possible to improve tear resistance while maintaining excellent overall properties of the multilayer fabric. At least one layer of the inflatable part may include the first region in an area proportion of 5% to 50% of the total area of ​​the corresponding layer. Within this range, a sufficient improvement in tear resistance may be demonstrated, and excellent airtightness may be shown even when the inflatable part is rapidly deployed due to a sudden influx of air. Two or more types of fabrics, including 1 / 1 taffeta, may be 1 / 1 taffeta and one or more fabrics selected from a group consisting of 2 / 1 twill, 3 / 1 satin, 2 / 2 Panama, and 3 / 3 Panama. When the non-1 / 1 taffeta fabric is 4 / 1, 5 / 1 or 4 / 4 fabric that is not the fabric mentioned above, the tear resistance may increase, but it may be difficult to use it for airbags due to deterioration in several characteristics, such as elongation and airtightness, which are essential as airbag fabrics. Among these, it is advantageous to use 1 / 1 taffeta and at least one selected weave from the group consisting of 2 / 1 twill and 3 / 1 satin as the two or more weave types, including 1 / 1 taffeta, because tear resistance can be improved while maintaining excellent durability of the multi-layered fabric. In particular, it is possible to produce a multi-layered fabric with excellent tear resistance and durability by using 1 / 1 taffeta and 2 / 1 twill as the two or more weave types, including 1 / 1 taffeta. Meanwhile, when the non-1 / 1 taffeta weave is inserted in both the warp and weft directions of the fabric layer, a different weave, such as 2 / 1 twill, 3 / 1 satin, 2 / 2 Panama, 3 / 3 Panama, or ripstop, can be implemented at a point where the non-1 / 1 taffeta weave intersects. For example, as shown in Figure 2, when 2 / 1 twill is inserted every certain number of 1 / 1 taffeta in both the warp and weft directions, 2 / 2 Panama will be implemented at the point where the 2 / 1 twill crosses. The first region can be inserted into the outermost fabric layer of the multi-layered fabric to prevent Lrornn / zznz / E / YiAi effectively means that the multi-layered fabric can be torn by an external sharp object. When the multi-layered fabric is a double-layered fabric, the first region can be inserted into both layers of fabric, and when the multi-layered fabric has three or more layers of fabric, the first region can be inserted into the two outer layers of fabric. The yarn for weaving the multilayer fabric can be, for example, nylon 66, nylon 6, nylon 46, nylon 610 or nylon 612 individually, or a polyamide fiber obtained by copolymerization or a mixture thereof; or polyethylene terephthalate, polytrimethylene terephthalate, polybutylene terephthalate or polyethylene naphthalate individually, or a polyester fiber obtained by copolymerization or a mixture thereof. The yarn fineness for weaving the multi-layer fabric can range from 300 to 700 dtex. Within this range, it can be inflated into the desired shape while meeting the required characteristics for deployment and expansion, and the bubble becomes flexible to improve storage properties, resulting in high-speed deployment. Multilayer fabric can exhibit excellent tear resistance by incorporating the inflatable portion woven into the characteristic pattern described above. Specifically, in the first region of the multilayer fabric, the warp-directed tear resistance, measured according to ISO 13937-2, can range from 300 to 800 N, 400 to 750 N, 500 to 700 N, 550 to 650 N, or 600 to 650 N, while the weft-directed tear resistance can range from 350 to 900 N, 450 to 850 N, 500 to 800 N, 600 to 800 N, 650 to 750 N, or 700 to 750 N. Furthermore, although the multi-layer fabric exhibits excellent tear resistance, it can also display high tensile strength and elongation similar to that of a conventional 1 / 1 taffeta fabric. Specifically, in the first region of the multi-layer fabric, the tensile strength in the warp direction, measured according to ISO 13934-1, can be 3200 to 3500 N / 5cm, 3300 to 3500 N / 5cm, or 3400 to 3500 N / 5cm, and the tensile strength in the weft direction can be 2800 to 3300 N / 5cm, 3000 to 3300 N / 5cm, 3050 to 3300 N / 5cm, or 3100 to 3300 N / 5cm. Furthermore, in the first region of the multilayer fabric, the elongation in the warp direction measured according to ISO 13934-1 can be 25% to 45%, 30% to 45% or 35% to 45%, and the elongation in the weft direction can be 20% to 40%, 25% to 40% or 27% to 40%.The methods for measuring tear strength, tensile strength, and elongation are specified in test examples that will be described later. When multi-layer fabric is used in a vehicle airbag, one or both surfaces of the multi-layer fabric may be coated to prevent air leakage through gaps in the fabric. The multi-layer fabric may be coated with a resin commonly used for fiber coating, and may include, but is not limited to, a silicone resin, a urethane-based resin, an olefin-based resin, or a mixture thereof. The multi-layer fabric may be coated with the resin using a knife coating method, a scraper-blade method, a spray coating method, or a similar method, and the resin may preferably be applied using a knife coating method. The coating of multi-layer fabric can be carried out using a multi-step coating method, applying the coating two or more times. When using a multi-step coating method LFornn / zznz / E / YiAi steps, can improve airtightness and can ensure flexibility by reducing the thickness of the fabric compared to the amount of coating. The resin coating amount can be adjusted from approximately 30 g / m² to 150 g / m², approximately 50 g / m² to 150 g / m², approximately 60 g / m² to 150 g / m², or approximately 70 g / m² to 150 g / m². Consequently, it is possible to provide a lightweight, multi-layered fabric with excellent air pressure resistance and storage properties without causing problems such as a decrease in blocking strength due to surface adhesion or an increase in cost. When the resin is applied by coating in a multi-step coating method, the effect described above can be further maximized by adjusting the amount of coating of the base coating layer to 60 to 75 g / m2. Meanwhile, according to another embodiment of the present disclosure, an airbag formed by the multi-layered fabric is provided. The multi-layered fabric not only exhibits excellent properties of a single-piece woven fabric but also significantly improves tear resistance with the specific weave pattern described above and is therefore not easily ruptured by fragments of broken glass. Consequently, the airbag formed by the multi-layered fabric can adequately protect a driver or passenger from fragments of broken glass even in the event of a rollover. Advantageous effects The multi-layered fabric according to one modality of this disclosure can provide an airbag capable of adequately protecting a driver or passenger by minimizing damage caused by fragments of broken glass when a vehicle rolls over. Brief description of the drawings Figure 1 shows a cross-section of a double-layered fabric according to one embodiment of the present disclosure. Figure 2 is a weave diagram of the first region in which 2 / 1 twill is inserted into 1 / 1 plain weave according to a modality of the present disclosure. Figure 3 shows a weave structure of a double-layered fabric that includes the first region of Figure 2 Figure 4 is a weave diagram of a fabric showing 1 / 1 taffeta from comparative example 1. Figure 5 shows a weaving structure of a double-layered fabric according to the fabric weaving diagram in Figure 4. Detailed description of modalities The function and effect of the present invention will be described in more detail below. Lrornn / zznz / E / YiAi through specific examples. However, these examples are for illustrative purposes only, and the invention is not intended to be limited by these examples. Example 1: Preparing the double-layer fabric A double-layer fabric was prepared on a jacquard machine using 470 dtex polyamide yarn (nylon 66). The double-layer fabric, as shown in Figure 1, has a structure in which two separate layers of fabric and the outer periphery of the two layers of fabric are woven together, and are woven at once by a one-piece weaving method. The two separate layers of fabric were prepared to include a first woven region in such a way that a 2 / 1 twill was placed every three 1 / 1 plain weaves in warp and weft directions, respectively, as shown in Figures 2 and 3. After applying 75 g / m2 of silicone resin per coating on both sides of the prepared double-layer fabric with a blade, the temperature was gradually raised to 90 to 150sC to perform the primary cure, followed by a heat treatment at 180sC to prepare a coated double-layer fabric. Example 2: Preparing the double-layer fabric A double-layered coated fabric was prepared in the same manner as in example 1, except that the first region was woven in such a way that a 2 / 1 twill was placed every five 1 / 1 plain weaves in the warp and weft directions. Example 3: Preparing the double-layer fabric A double-layered coated fabric was prepared in the same manner as in example 1, except that the first region was woven in such a way that a 2 / 1 twill was placed every eleven 1 / 1 plain weaves in the warp and weft directions. Example 4: Preparing the double-layer fabric A double-layered coated fabric was prepared in the same manner as in example 1, except that the first region was woven in such a way that a 2 / 1 twill was placed every thirteen 1 / 1 plain weaves in both warp and weft directions. Example 5: Preparing the double-layer fabric A double-layered coated fabric was prepared in the same way as in example 2, except that the weave pattern was changed so that 3 / 1 satin was placed instead of 2 / 1 twill in the first region of example 2. Comparative Example 1: Preparation of Double Layer Fabric A coated double-layer fabric was prepared in the same way as in Example 1, except that the double-layer fabric was prepared by weaving only 1 / 1 plain weave as shown in Figures 4 and 5. Example test: Evaluation of the physical properties of the double-layer fabric Five samples were prepared from each of the first regions of the double-layer fabrics prepared in Examples 1 to 5, and five samples were prepared from the double-layer fabric prepared in Comparative Example 1. The physical properties of the prepared samples were then evaluated by the Leoenn / zznz / E / YiAi method described below, and the average value was obtained and shown in Table 1. 1. Tear resistance The warp and weft tear strengths of the prepared samples were measured. Tear strength was measured according to ISO 13937-2 after the sample had been left at room temperature for 24 hours, and the warp and weft tear strengths were measured, respectively, followed by calculating the average value. 2. Elongation The elongation in the warp and weft directions of the prepared samples was measured. Elongation was measured according to ISO 13934-1 after the sample had been left at room temperature for 24 hours, and the elongation in the warp and weft directions was measured, respectively, followed by obtaining an average value. 3. Tensile strength The tensile strength in the warp direction and the tensile strength in the weft direction of the prepared samples were measured. Tensile strength was measured according to ISO 13934-1 after the sample had been left at room temperature for 24 hours, and the tensile strength in the warp and weft directions were measured, respectively, followed by calculating an average value. Table 1 LFornn / zznz / E / YiAi Separation of insertion of non-taffeta fabric of 1 / 1 Tear strength (warp direction, N) Tear strength (weft direction, N) Elongation (warp direction, %) Elongation (weft direction, %) Tensile strength (warp direction, N / 5cm) Tensile strength (weft direction, N / 5cm) Example 1 3 589 700 36 27 3405 3309 Example 2 5 614 708 38 29 3440 3057 Example 3 11 410 458 39 30 3395 3128 Example 4 13 307 366 40 30 3426 3196 Example 5 5 525 494 28 25 3201 2863 Comparative example 1 0 256 305 41 32 3453 3271 Referring to Table 1, it has been confirmed that even if the first region of the multilayer fabric according to a modality of the present disclosure is formed by two or more types of fabrics, including 1 / 1 taffeta, the multilayer fabric shows significantly improved tear resistance while exhibiting elongation and tensile strength almost equal to those of the double-layer fabric (comparative example 1) formed only with 1 / 1 taffeta. Consequently, it has been confirmed that the multilayer fabric according to the modality can provide an air cushion that is not damaged or can minimize damage from broken glass fragments.

Claims

1. A multi-layer fabric comprising an inflatable part; and a jointly woven part surrounding the inflatable part, wherein at least one layer of the inflatable part comprises a first region formed by two or more types of fabrics comprising 1 / 1 taffeta.

2. The multi-layer fabric according to claim 1, wherein the first region is formed by inserting a non-1 / 1 taffeta fabric every 2 to 15 1 / 1 taffeta.

3. The multi-layer fabric according to claim 1, wherein the first region is formed by inserting a non-1 / 1 taffeta fabric every 2 to 15 1 / 1 taffeta in the warp and weft directions.

4. The multi-layer fabric according to claim 1, wherein the first region is formed by inserting 1 to 5 different 1 / 1 taffeta fabrics every 2 to 15 1 / 1 taffeta.

5. The multilayer fabric according to claim 1, wherein the first region comprises an area proportion of 5% to 50% of the total area of ​​the layer.

6. The multi-layer fabric according to claim 1, wherein the first region is formed by 1 / 1 taffeta and at least one fabric selected from the group consisting of 2 / 1 twill, 3 / 1 satin, 2 / 2 Panama, and 3 / 3 Panama.

7. The multi-layer fabric according to claim 1, wherein the first region is formed by 1 / 1 taffeta and at least one fabric selected from the group consisting of 2 / 1 twill and 3 / 1 satin.

8. The multi-layer fabric according to claim 1, wherein a region other than the first region is a second region formed by 1 / 1 taffeta.

9. The multilayer fabric according to claim 1, wherein the first region has a tear strength of 300 to 800 N in the warp direction and a tear strength of 350 to 900 N in the weft direction, measured according to ISO 13937-2.

10. The multi-layer fabric according to claim 1, wherein the first row has a tensile strength of 3200 to 3500 N / 5cm in the warp direction and a tensile strength of 2800 to 3300 N / 5cm in the weft direction, measured according to ISO 13934-1.

11. The multi-layer fabric according to claim 1, wherein the first region has elongation in the warp direction of 25% to 45% and elongation in the weft direction of 20% to 40%, measured according to ISO 13934-1.

12. An air bag formed by the multi-layer fabric according to claim 1.

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