JP7724291B2 - Warp knit spacer mesh fabric provides breathability, elasticity and support - Google Patents

Description

[Related Applications]
This application claims priority to PCT application PCT/CN 2021/086319, filed April 11, 2021, which is incorporated herein by reference in its entirety.

One or more embodiments relate to a warp-knitted spacer fabric having one or more warp-knitted mesh layers, a cushioning layer made of the spacer fabric, a composite material made of the spacer fabric, a trim cover made of the spacer fabric, and methods for manufacturing the same. At least one or more specific other embodiments relate to a process for manufacturing a warp-knitted 3D spacer mesh fabric, particularly a warp-knitted 3D fabric with high magnetic permeability and high resilience.

As people's living standards continue to improve, people's demands for comfort (softness, elasticity, breathability) and environmental protection of automobile seat cushions are also increasing. A layer of foam, such as polyurethane foam, is commonly used underneath conventional automobile seat cushions. In some cases, it may be desirable to reduce or minimize the use of polyurethane foam.

Spacer fabric is versatile and can therefore be used in many different applications. Spacer fabric is flexible and easily bends. Spacer fabric is also breathable. Another feature found in most spacer fabrics is their resilience.

The various advantageous properties of the spacer fabric allow it to be used in a variety of applications, including, but not limited to: furniture such as seats, mattresses, and upholstered products; vehicle components such as climate and non-climate automotive seats, trim and seat covers, trim panels such as door panels, dashboards, consoles, and headliners; and wearable products such as athletic shoes and clothing.

Warp-knitted 3D mesh fabrics have been gradually applied to partially or completely replace polyurethane foam in certain applications due to their soft elasticity and environmentally friendly properties. However, warp-knitted 3D mesh fabrics applied in this field have been found to have limited, and in some cases insufficient, stability of the intermediate connecting support monofilaments.
In some instances, it has been found that when the intermediate connecting support monofilaments are compressed by fabrics above and below the 3D fabric, the intermediate connecting support monofilaments can relatively easily collapse laterally or become compressed under pressure, thereby compromising their ideal resilience and comfort.

Additionally, the spacer fabric can be used as a composite or trim material. A suitable composite material includes a spacer fabric sandwiched between a cover layer, which can be decorative, such as leather, vinyl, or fabric, and a base, which can be a rigid or flexible base layer.

In at least certain embodiments, the present disclosure aims to overcome recognized deficiencies of the prior art and provide warp-knitted 3D fabrics that have relatively high breathability and elastic recovery.

In one embodiment, a spacer fabric is provided that includes a first knit layer, a second knit layer, and a third layer that includes a monofilament spacer yarn extending between the first knit layer and the second knit layer and connecting the first knit layer and the second knit layer to form an integral three-dimensional network structure. In at least one embodiment, the spacer fabric has relatively high permeability.

Generally, the larger the voids (pore size) within the fabric (both top and bottom), the better the air volume, provided the basic functionality of the fabric is ensured. The comfort and support of the spacer fabric are related to its elasticity and recovery, which in turn is related to the stiffness of the connecting monofilaments and the ability of the upper and lower fabrics to hold the connecting monofilaments. In at least one embodiment, the first layer is a mesh layer forming the top fabric, and the second layer is a plain, or generally solid, layer forming the bottom fabric, with the first and second layers having unique structures. These structures not only ensure good grip, but also allow the monofilament connections to have good breathability.

FIG. 1 is a schematic perspective view of a spacer fabric according to one embodiment of the present disclosure. FIG. 2 is a photograph of one embodiment of the spacer fabric of FIG. FIG. 3 is an enlarged exploded view of one embodiment of a spacer fabric showing schematic details of an embodiment of a layer of the spacer fabric. FIG. 4 is a photograph at 10x magnification of an embodiment of the first layer mesh fabric. FIG. 5 is a schematic digital image of an embodiment of a first layer mesh fabric. FIG. 6A is an illustration of first layer yarn movement in an embodiment of a first layer mesh fabric. FIG. 6B is an illustration of first layer yarn movement for a first layer mesh fabric embodiment. FIG. 7 is an illustration of the operation of the first layer yarns of an embodiment of the first layer fabric. FIG. 8 is an illustration of the operation of the first layer yarns of one embodiment of the first layer mesh fabric. FIG. 9 is a photograph at 10x magnification of one embodiment of the second layer plain fabric. FIG. 10 is a single yarn movement diagram showing the movement of the yarn in the second layer of the fabric. FIG. 11 illustrates the operation of the second layer yarns in an embodiment of the second layer of the fabric. FIG. 12 is a diagram of the warp knitting of the 3D spacer mesh fabric. FIG. 13 is an illustration of the operation of first layer yarns of a first layer mesh fabric according to another embodiment. FIG. 14 is an illustration of the operation of first layer yarns of a first layer fabric according to another embodiment. FIG. 15 is an illustration of the operation of first layer yarns of a first layer mesh fabric according to another embodiment. FIG. 16 is a photograph at 10x magnification of a first layer mesh fabric according to another embodiment.

As required, detailed embodiments of the present disclosure are disclosed herein.
It should be understood, however, that the disclosed embodiments are merely exemplary of the disclosure, which may be embodied in various alternative forms. The figures are not necessarily to scale. Some features may be exaggerated or minimized to show details of particular components. Therefore, specific structural and functional details disclosed herein should not be construed as limiting, but merely as a representative basis for teaching those skilled in the art how to variously use the present disclosure.

Referring to Figures 1 and 2, an exemplary spacer fabric 10 of the present disclosure is described. The spacer fabric 10 can be used in a variety of applications. In one embodiment, the spacer fabric 10 can be used as a seat cushion layer, with or without a corresponding foam layer, such as a layer of polyurethane foam. The spacer fabric 10 can be used as a cushion or cushion component in any cushioning application, such as a seat bottom, seat back, and/or trim panel.

In other embodiments, the spacer fabric 10 can be used as a trim layer component, where the spacer fabric 10 is secured beneath a trim layer. In such embodiments, any suitable trim layer can be used, including, but not limited to, leather, synthetic leather, plastics such as vinyl, and fabric layers. The trim or decorative layer can hold the spacer fabric 10 in place by any suitable technique, such as, for example, stitching or adhesive.

In other embodiments, the spacer fabric 10 can be used as a composite material requiring a certain level of elasticity and/or breathability. It should be readily understood that composite materials made with the spacer fabric 10 of the present disclosure can be other automotive or non-automotive composite materials.

As shown generally in Figures 1-3, the spacer fabric 10 includes a mesh-like first knit layer 12, a generally stiff or closed (i.e., flat) second knit layer 14, and spacer yarns 16 extending between and connecting the first knit layer 12 and the second knit layer 14.

In some other embodiments, the spacer fabric 10 comprises a warp-knitted 3D mesh fabric having a top warp-knitted mesh fabric layer 12, a bottom warp-knitted fabric (no mesh) layer 14, and monofilaments 16 woven into the top and bottom layers 12 and 14 to form an integral 3D network structure 10.

In certain other embodiments, as will be described in more detail further below, the spacer fabric 10 of the present disclosure has relatively high breathability, resiliency, and support compared to other fabrics. In this regard, the spacer fabric 10 of the present disclosure is particularly suited for use in the lower cushioning material of automobile seats. In at least certain embodiments, the mesh forming the upper fabric 12 and the flat cloth forming the lower fabric 14 have a unique structure, as representatively shown in the figures.

In one embodiment, the two knit layers 12 and 14 have stitch wales running in the production direction and stitch courses running in the cross direction. The spacer yarn 16 extending between and connecting the first knit layer 12 and the second knit layer 14 can be any suitable monofilament yarn.

In certain other embodiments, the top layer 12 and bottom layer 14 are made of a conventional multi-strand polyester filament. In at least one embodiment, the top layer 12 and bottom layer 14 are made of a conventional multi-strand polyester filament having a size of 83 dtex/36F and an intermediate connecting monofilament 16 having a size of 33-44 dtex/1F. It should be understood that other sizes and/or types of yarns may be used and are consistent with this disclosure.

In at least some other embodiments, the interlayer yarn 16 should have good stiffness and elasticity. In some other embodiments, the size and thickness of the monofilament can be selected depending on the desired compressive strength and springback deformation characteristics to be achieved. In at least some other embodiments, the size of the monofilament yarn 16 is 33-44 dtex. It should be understood that other sizes and/or types of monofilaments can be used and are consistent with this disclosure.

As best seen in Figures 4-5, the first layer 12 has openings 8. In at least some embodiments, the openings in the top layer 12 are shown to be generally oval-shaped, however, the openings 8 may be any suitable shape, such as elongated, circular, square, and/or rectangular, to name a few. The size of the openings 8 on the top layer 12 can be tailored to any suitable size as needed. Generally, larger openings 8 provide better airflow, but increasing the size of the openings 8 reduces support. In at least one embodiment, the top layer 12 has greater breathability than the bottom layer 14.

An image of an exemplary embodiment of the first knit layer 12 is shown in Figure 5. As shown, the first knit layer 12 has an open mesh structure. As representatively shown in the illustrated embodiment, the open mesh structure of the first knit layer 12 has a plurality of strips 6 separated by a plurality of spaced openings 8.

In at least the illustrated embodiment, the openings 8 are generally oval and extend in separate, offset, staggered rows. In at least one embodiment, the openings 8 are arranged in staggered rows. In at least one embodiment, the openings 8 are spaced 0.5 to 10 mm apart on center across the width and 0.5 to 10 mm apart on center across the length.

As shown schematically in one embodiment in Figures 3 and 12, the spacer fabric 10 can be manufactured on a warp knitting double needle bar machine. As shown schematically and representatively, five pattern bars 11, 13, 15, 17, and 19 are used to guide yarns 21, 23, 25, 27, and 29 to needles 31 and 33. Pattern bars 17 and 19 are used to guide yarns 21 and 23 to needle 31 for knitting the first layer of mesh fabric 12. Pattern bars 13 and 15 are used to guide yarns 25 and 27 to needles 31 and 33 for knitting support monofilament 16. Pattern bar 11 is used to guide yarn 29 to needle 33 for knitting underlay fabric 14.

The first layer 12 has an open mesh structure, as shown schematically in Figures 4 and 12. Figures 6A and 6B show an embodiment of a motion chart for a suitable single-yarn stuffing yarn on two pattern bars. The motion chart for the stuffing yarn is a coil formed by the needles from bottom to top. The horizontal row of dots represents the needles arranged in order on the needle bed. The top of point 22 represents the front of the needle hook, and the bottom of point 22 represents the rear of the needle. Yarn 21 swings through pattern bar 19, where needle 31 hooks the stuffing yarn and returns to the other side to complete the motion. The motion rules are shown in the motion curves for yarns 21 and 23 in Figures 6A and 6B. Similarly, yarn 23 completes the above-described stuffing motion through pattern bar 17.

As shown representatively in Figures 6A and 6B for the first layer 12 of the fabric fill yarn motion diagram, the fill yarn motion diagram shows the coils formed by the needles in order with dotted lines (as indicated by 22) from bottom to top. Horizontal dots are used to represent the sequentially arranged needles (N1/N2/N3/N4/N5/N6/N7/N8), with the top of dot 22 indicating the front of the needle hook and the bottom of dot 22 indicating the rear of the needle. Continuous line segments are used to represent the movement of the yarn guide needles of the pattern bar in the needle-forward and needle-rearward positions. Generally, the numbering (digitization) of the fills is 0, 1, 2, 3, 4, 5, 6, 7, 8... in needle-to-needle order from right to left, and is used to represent the pattern bar motion trajectory in needle-to-needle order from right to left. C1-C12 indicate row C of the yarn looped from bottom to top. Arrows 47 and the like indicate the direction of travel of the yarns 23 leading through the pattern bar 17. The motion rules for all yarns 23 on the pattern bar 17 are the same, at least in the illustrated embodiment, although it should be understood that other motion rules may be used. In the illustrated embodiment, the stitch formations on one side of the pattern bar 17 are recorded as 1-0/1-2/1-0/1-2/7-8/7-6/7-8/7-6//, where "1-0" corresponds to 39 in the C1 course, "1-2" corresponds to 40 in the C2 course, "1-0" corresponds to 41 in the C3 course, "1-2" corresponds to 42 in the C4 course, "7-8" corresponds to 43 in the C5 course, "7-6" corresponds to 44 in the C6 course, "7-8" corresponds to 45 in the C7 course, and "7-6" corresponds to 46 in the C8 course in FIG. 6 . The movement of the yarn cushion of pattern bar 19 is completely symmetrical to the movement of pattern bar 17. The fill yarns of pattern bar 19 are recorded as follows in the illustrated embodiment: 7-8/7-6/7-8/7-6/1-0/1-2/1-0/1-2//. The numbers represent the mesh stitch formation of one bar when both bars work together to create the mesh pattern. Also, the main explanation of all the following fill operation diagrams is the same as the explanation in this paragraph, with only the fill operation rules differing.

The first layer 12 has an open mesh structure, as shown in the embodiments shown in Figures 4, 7, and 8. In the embodiment shown in Figure 7, the movement diagram of a single pattern bar shows that the yarn threading pattern on the same pattern bar is a series of three consecutive yarns 51 separated by one gap 53 in this cycle, with no connecting yarn between the two longitudinal directions of the hollow section, forming mesh openings 8. In this embodiment, the yarn pattern is a 3-in, 1-out threading pattern that is repeated throughout the machine. It should be understood that some deviations from the ranges described and illustrated above are consistent with this disclosure.

As shown in the illustrated embodiment, yarns 21 and 23 on the two pattern bars are symmetrically guided into the needle hooks according to the operating rules of FIGS. 6A, 6B, and 8. In at least one embodiment, coils in adjacent warp lines are not connected, but rather, as shown in FIGS. 4 and 8, they are inclined in opposite directions to form mesh openings 8, and coils in adjacent warp lines are connected and adjacent to each other to form strips of fabric 6. The open mesh structure of the first knit layer 12 has a plurality of openings 8 and strips of fabric 6. In at least one embodiment, as shown in the example of FIG. 8, the openings 8 have four courses in length, but it should be understood that the openings 8 can have any suitable size, with the corresponding number of coils being increased or decreased as needed, depending in particular on the desired level of breathability. In at least one embodiment, the strips of fabric 6 have four wales in width, as shown in the examples of FIGS. 4 and 8, and four courses in length between mesh openings, as shown in the example of FIG. 6, but can have any suitable size. While most, if not all, openings will fall within the above ranges, it should be understood that some may fall outside of the above ranges and are within the scope of this disclosure.

A second embodiment of the first layer 12 having an open mesh structure is shown schematically in Figures 13-16. In the embodiment shown in Figure 4, the operational diagram of a single pattern bar shows that the yarn threading rule on the same pattern bar is a continuation of this cycle of three threads 26 separated by a single void 61. As shown in this embodiment, there is no connecting yarn between the two longitudinal directions of the hollow section, forming mesh openings 63. It should be understood that deviations from the above scope are consistent with this disclosure.

In the embodiment of the first layer 12 having an open mesh structure shown in Figures 13-16, the yarns 30 and 71 on the two pattern bars are symmetrically guided into the needle hooks according to the operating rules of Figures 13 and 15. In at least one embodiment, the coils in adjacent warp lines are not connected, but rather, as shown in Figures 15 and 16, they are inclined in opposite directions to form mesh openings 63, and the coils in adjacent warp lines are connected and adjacent to each other to form a strip of fabric 28. The open mesh structure of the first knit layer 12 has a plurality of openings 63 and fabric 28. In at least this embodiment, the openings 63 have a length of six courses, as shown in the example of Figure 15. Although the openings 29 are shown in the example of Figure 15, they can have any suitable size, possibly by increasing or decreasing the corresponding number of coils as needed, particularly based on the desired breathability level. In at least this embodiment, the strip of fabric 28 has four wales, as shown in the examples of Figures 15 and 16, and six courses in width, as shown in the example of 67 of Figure 13. However, it should be understood that the length between mesh openings can have any suitable size. It should be understood that while most, if not all, openings will fall within the above ranges, some may fall outside the above ranges and still be consistent with the current disclosure.

One embodiment of the second layer structure 14 is shown in Figures 9-11. As shown in the example of Figure 12, a single pattern bar introduces enough threaded bars onto the knitting needles so that each needle is covered with yarn and knits the yarn onto each needle.

In the second layer structure 14 embodiment shown in Figures 9-11 and the example shown in Figure 12, the pattern bar 11 drives the yarn 29 and directs it to the hook 33 according to the motion rule 69 in Figure 10. An embodiment of the knitted fabric is shown in Figure 9.

In the second layer structure 14, as shown in the embodiment of Figures 9-11, the fabric structure of this layer is a smooth-textured, generally solid (i.e., no mesh generation) fabric that traverses two or more needles, and a single pattern bar directs the yarn to the needles according to the embodiment shown in Figures 10 and 11. The length of the extension line 38 is related to the crosswise density of the fabric and also to the number of needles through which the yarn passes as it is fed; the more needles that are passed through or the lower the crosswise density of the fabric, the longer the corresponding extension line 38.

It should be noted that prior art methods typically use two pattern bars to direct the yarns, which makes the structure very stiff and less elastic. At least one embodiment of the present disclosure's second layer structure 14 uses a single pattern bar, making the structure soft and elastic. The length of the extension line 38 shown in Figures 9 and 10 helps determine the elasticity of the fabric.

In the intermediate connecting monofilament 16 shown in Figures 1-3 and 12, at least in the embodiment shown in Figure 12, two pattern bars 13 and 15 drive the yarns 25 and 27, directing them to the needle hooks 31 and 33.

In the intermediate connecting monofilament 16 structure having the first knit layer 12 and the second knit layer 14 shown in Figures 1-3, at least in the illustrated embodiment, two pattern bars symmetrically pack yarn and are involved in knitting the first knit layer 12 and the second knit layer 14, respectively. Therefore, the monofilament 16 can firmly connect the two knit layers 12 and 14, forming a 3D network structure 10. The first knit layer 12 and the second knit layer 14 can firmly hold and connect the monofilament 16 through the structures 6 and 14 in Figures 4 and 9, thereby firmly holding and fixing the connecting monofilament 16. In at least one embodiment, the thickness of the 3D spacer mesh fabric can be determined by the length of the connecting monofilament 16. In at least one embodiment, the thickness of the fabric is 9-10 mm, but it should be understood that this is by way of example only and the thickness can be adjusted as needed within the present disclosure.

In at least certain other embodiments, to achieve a spacer fabric 10 that is soft, comfortable, elastic, and has good breathability, the layers, and in certain embodiments, the top layer 12, include mesh openings 8 and fabric layer spacing arranged in a flat pattern 6, with the mesh allowing the fabric to have excellent breathability. In certain embodiments, the mesh size can be adjusted according to desired ventilation requirements. The flat knit section helps make the intermediate connecting monofilaments 16 and the top fabric 12 more stable and rigid. Therefore, the stability and straightness of the intermediate connecting monofilaments 16 are relatively good, and the monofilaments can be prevented from tilting and/or bundling. The mesh distributes the monofilaments 16 relatively evenly, distributing forces over a relatively large surface area and helping to avoid localized collapse. In at least certain other embodiments, the monofilaments have good stability and are less likely to collapse laterally due to the flat knitting reinforcement, and the elastic recovery of the fabric is improved compared to other fabrics.

In at least one embodiment, the spacer fabric 10 has a thickness of 8 to 12 mm, in another embodiment 8.5 to 11 mm, and in yet another embodiment 10 mm.

The resilience and support of the 3D spacer fabric 10 are related to the stiffness of the monofilaments 16, the structure of the fabric, and the vertical and horizontal densities. The upper and lower fabric structures 12 and 14 described above can better hold the connecting monofilaments 16, thereby helping to prevent lateral retention of the filaments 16 under external pressure, which helps to prevent poor resilience and support of the fabric. Furthermore, if the stiffness of the intermediate connecting monofilaments 16 is too high or too low, the resilience and comfort of the fabric will be poor. As the vertical and horizontal densities of the fabric increase, support will be stronger. In at least one embodiment, the resilience and support of the fabric are measured by a compressive stress value of 5±2 kPa, but are not limited to this value. In at least one embodiment, the spacer fabric 10 of the present disclosure has a compressive stress value of approximately 4.2 kPa. Compressive stress values can be measured according to test method DIN EN ISO 3386-1, Vbrkraft 0.1 Pa; 80 x 80 mm/100 mm/min.

The high breathability of the three-dimensional spacer fabric 10 is related to the gap between the upper fabric 12 and the lower fabric 14. Generally speaking, the larger the gap, the better the breathability, but the size of the fabric gap can limit resilience and support. In at least one embodiment, the breathability of the spacer fabric 10 is typically ≥ 3500 mm/s, but is not limited to this value. In at least one embodiment, the spacer fabric 10 of the present disclosure has a breathability of approximately 5000 mm/s. Breathability can be measured according to the test method: DIN EN ISO 9237, 2 mbar, test sample: 20 ^cm2 .

While exemplary embodiments have been described above, it is not intended that these embodiments describe all possible forms of the disclosure. Rather, the words used in the specification are words of description rather than limitation, and it is understood that various changes can be made without departing from the spirit and scope of the disclosure. Moreover, features of various embodiments can be combined to form further embodiments of the disclosure.

Claims (17)

a first knit layer; and
a second knit layer; and
a spacer yarn extending between and connecting the first and second knit layers;
Including,
the first knit layer has a mesh structure including a plurality of spaced apart openings separated by flat fabric portions, each of the flat fabric portions including a series of three yarns;
the second knit layer has a flat structure;
The spacer fabric has a compressive stress value of 5±2 kPa and an air permeability of ≧3500 mm/s. The spacer fabric of claim 1 , wherein the openings are generally circular, elongated, oval, square, and/or rectangular in shape. 2. The spacer fabric of claim 1 , wherein the openings are spaced 0.5 to 10 mm apart at the center of the openings in the width direction and 0.5 to 10 mm apart at the center of the openings in the length direction. The spacer fabric of claim 1, wherein the first and second knit layers, together with the spacer yarn, form an integral three-dimensional network structure. The spacer fabric of claim 1, wherein the spacer fabric comprises a cushioning layer in a vehicle seat trim cover. The spacer fabric of claim 1, wherein the first knit layer has higher breathability than the second knit layer. The spacer fabric of claim 1, wherein each of the plurality of spaced openings in the first knit layer is bounded by three yarn strands. The spacer fabric of claim 1, wherein each of the plurality of openings includes one wale in width and four courses in length. 9. The spacer fabric of claim 8 , wherein each of said fabric portions comprises four wales in width and four courses in length. The spacer fabric of claim 1, wherein each of the plurality of openings includes one wale in width and six courses in length. 11. The spacer fabric of claim 10 , wherein each of the fabric portions comprises four wales in width and six courses in length. a first knit layer; and
a second knit layer; and
a spacer yarn extending between and connecting the first and second knit layers;
Including,
the first knit layer has a mesh structure including a plurality of spaced apart openings separated by flat fabric portions, each of the flat fabric portions including a series of three yarns;
A spacer fabric, wherein each of the plurality of openings comprises one wale in width and at least four courses in length. The spacer fabric of claim 12 , wherein each of the plurality of openings comprises six courses in length. The spacer fabric of claim 12 , wherein each of the fabric portions comprises four wales in width and at least four courses in length. The spacer fabric of claim 14 , wherein each of the fabric portions comprises six courses in length. The spacer fabric of claim 12 , wherein the spacer fabric has a compressive stress value of 5±2 kPa and an air permeability of ≧3500 mm/s. The spacer fabric of claim 12 , wherein the spacer fabric has a thickness of 8 to 12 mm.