EP4667634A1

EP4667634A1 - Fiber structure, shoe, clothing item, bag, and method of manufacturing fiber structure

Info

Publication number: EP4667634A1
Application number: EP25183549.2A
Authority: EP
Inventors: Chihaya SUZUKI
Original assignee: Asics Corp
Current assignee: Asics Corp
Priority date: 2024-06-19
Filing date: 2025-06-18
Publication date: 2025-12-24
Also published as: JP2026001441A; US20250389064A1; CN121157447A

Abstract

To provide a fiber structure 100 at least part of which has a layer structure including a first fiber layer 110, a second fiber layer 120, and a third fiber layer 130 that are arranged parallel to one another, a first suspension layer 140 that is composed of a weaving yarn or a knitting yarn stretched between the first fiber layer 110 and the second fiber layer 120, and a second suspension layer 150 that is composed of a weaving yarn or a knitting yarn stretched between the second fiber layer 120 and the third fiber layer 130. The fiber structure 100 can be adopted particularly as a material of shoes, clothing items, bags, and the like required to have various functions.

Description

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to Japanese Patent Application No. 2024-098778 , the disclosures of which are incorporated herein by reference in their entirety.

BACKGROUND

Technical field

The present invention relates to a fiber structure, a shoe, a clothing item, a bag, and a method of manufacturing a fiber structure.

Background Information

In the footwear industry, in some cases, shoe uppers are formed using a fiber structure called a double russel mesh including a front layer, a back layer, and an intermediate layer vertically connecting the front layer to the back layer with a yarn. The intermediate layer allows the double russel mesh to constitute, for example, a layer having a function such as impact buffer properties. Such a fiber structure is adopted, for example, in various items other than shoes, such as vehicle seats (see, for example, Japanese Unexamined Utility Model Application Publication No. H6-26700 ).

SUMMARY

As described above, a double russel mesh constitutes a single layer, and thus in shoes, it is difficult to laminate layers having functions, for example, to laminate an outer layer that has high repulsive properties for an external impact on an inner layer that has high impact buffer properties and is in contact with the foot. As an example other than shoes, Japanese Unexamined Patent Application Publication No. 2019-15106 discloses a sound absorbing material formed by laminating, with an adhesive, three-dimensional knitted materials including a front layer, a back layer, and an intermediate layer vertically connecting the front layer to the back layer with a yarn. Using such an example as a reference, for example, double russel meshes may be laminated with an adhesive; however, laminating double russel meshes causes problems such as weight increase due to the adhesive, the possibility of peeling off, and a complicated manufacturing process.
The present disclosure has been made to solve such problems, and provides a fiber structure and the like that include laminated layers having functions and are lightweight, highly reliable, and easy to manufacture.
A fiber structure according to a first aspect of the present disclosure is a fiber structure at least part of which has a layer structure including a first fiber layer, a second fiber layer, and a third fiber layer that are arranged parallel to one another, a first suspension layer that is composed of a weaving yarn or a knitting yarn stretched between the first fiber layer and the second fiber layer, and a second suspension layer that is composed of a weaving yarn or a knitting yarn stretched between the second fiber layer and the third fiber layer.
A shoe according to a second aspect of the present disclosure is a shoe that adopts the fiber structure.
A clothing item according to a third aspect of the present disclosure is a clothing item that adopts the fiber structure.
A bag according to a fourth aspect of the present disclosure is a bag that adopts the fiber structure.
A method of manufacturing a fiber structure according to a fifth aspect of the present disclosure includes: a plane layer forming step of forming a first fiber layer, a second fiber layer, and a third fiber layer; and a suspension layer forming step of forming a first suspension layer by stretching a weaving yarn or a knitting yarn between the first fiber layer and the second fiber layer and forming a second suspension layer by stretching a weaving yarn or a knitting yarn between the second fiber layer and the third fiber layer.
A method of manufacturing a fiber structure according to a sixth aspect of the present disclosure includes: an outer layer forming step of forming a first fiber layer and a third fiber layer; and an inner layer forming step of forming a second fiber layer by causing, between the first fiber layer and the third fiber layer, a weaving yarn or a knitting yarn drawn from the first fiber layer toward the third fiber layer to cross a weaving yarn or a knitting yarn drawn from the third fiber layer toward the first fiber layer, forming a first suspension layer by causing the weaving yarn or the knitting yarn drawn from the first fiber layer to reach the second fiber layer and return to the first fiber layer, and forming a second suspension layer by causing the weaving yarn or the knitting yarn drawn from the third fiber layer to reach the second fiber layer and return to the third fiber layer.
The present disclosure can provide a fiber structure and the like that include laminated layers having functions and are lightweight, highly reliable, and easy to manufacture.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic perspective view illustrating a portion cut from a fiber structure according to the present embodiment.
FIG. 2 is a simplified diagram illustrating a cross section of a fiber structure according to a first embodiment.
FIG. 3 is a simplified diagram illustrating a cross section of a fiber structure according to a second embodiment.
FIG. 4 is a simplified diagram illustrating a cross section of a fiber structure according to a third embodiment.
FIG. 5 is a simplified diagram illustrating a cross section of a fiber structure according to a fourth embodiment.
FIG. 6 is a simplified diagram illustrating a cross section of a fiber structure according to a fifth embodiment.
FIG. 7 is a simplified diagram illustrating a first manufacturing method of the fiber structure.
FIG. 8 is a simplified diagram illustrating a second manufacturing method of the fiber structure.
FIG. 9 is a diagram illustrating an example of a fiber structure having a multilayer structure including more layers.
FIG. 10 is a diagram illustrating an example of a fiber structure part of which has a multilayer structure.
FIG. 11 is a front view illustrating an example in which the fiber structure is used in a clothing item.
FIG. 12 is a rear view illustrating an example in which the fiber structure is used in the clothing item.

DETAILED DESCRIPTION

The present invention will be described through embodiments of the invention; however, the invention according to the claims is not limited to the following embodiments. Furthermore, all the configurations described in the embodiments are not necessarily essential as a solution to the problem. In the drawings, components denoted by the same reference numerals have the same or similar configuration.
FIG. 1 is a schematic perspective view illustrating a portion cut from a fiber structure 100 according to the present embodiment. The fiber structure 100 according to the present embodiment includes a first fiber layer 110, a second fiber layer 120, and a third fiber layer 130 that are arranged parallel to one another, a first suspension layer 140 that is composed of a yarn stretched between the first fiber layer 110 and the second fiber layer 120, and a second suspension layer 150 that is composed of a yarn stretched between the second fiber layer 120 and the third fiber layer 130. Each of the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130 may be a knitted layer formed by interlacing a knitting yarn in a loop, or may be a woven layer formed by crossing a weaving yarn composed of a warp and a weft. Similarly, the first suspension layer 140 and the second suspension layer 150 may also be a knitted layer or a woven layer. In the following, for convenience, each of the layers is described as a knitted layer composed of a knitting yarn.
The first suspension layer 140 formed between the first fiber layer 110 and the second fiber layer 120 has a higher air permeability than each of the first fiber layer 110 and the second fiber layer 120. In other words, the first fiber layer 110 and the second fiber layer 120 are more densely knitted than the first suspension layer 140. The air permeability indicates the yarn ratio per unit space (in other words, "yarn density"), and the air permeability is low when the yarn ratio per unit space is high (the yarn density is high), and the air permeability is high when the yarn ratio per unit space is low (the yarn density is low). Similarly, the second suspension layer 150 formed between the second fiber layer 120 and the third fiber layer 130 has a higher air permeability than each of the second fiber layer 120 and the third fiber layer 130. In other words, the second fiber layer 120 and the third fiber layer 130 are more densely knitted than the second suspension layer 150. In such a layer structure, the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130 arranged parallel to one another mainly have the function of maintaining the strength in the plane direction, and the first suspension layer 140 and the second suspension layer 150 mainly have the function of providing cushioning properties and repulsive properties required in the layer direction.
In the present embodiment, as illustrated in the drawings, the plane direction of each of the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130 arranged parallel to one another is defined as an XY direction, and a direction perpendicular to the plane direction is defined as a Z-axis direction. In the present embodiment, the Z-axis direction may be referred to as a layer direction.
In the present embodiment, the fiber structure 100 having various characteristics can be obtained by adjusting the layer structures of the first suspension layer 140 and the second suspension layer 150. Thus, the layer structures of the first suspension layer 140 and the second suspension layer 150 will be described through embodiments of the fiber structure 100.
FIG. 2 is a simplified diagram illustrating a cross section of the fiber structure 100 according to a first embodiment. In the first embodiment, the first suspension layer 140 and the second suspension layer 150 have the same layer structure. That is, the distance between the first fiber layer 110 and the second fiber layer 120, which is the thickness of the first suspension layer 140, is the same as the distance between the second fiber layer 120 and the third fiber layer 130, which is the thickness of the second suspension layer 150, and the first suspension layer 140 and the second suspension layer 150 are composed of the same knitting yarn and formed by the same knitting method.
When the suspension layers having the same structure are laminated in this manner, it is possible to obtain a higher level of desired function (e.g., cushioning properties) that is not sufficiently achieved by a single layer.
Needless to say, the first suspension layer 140 and the second suspension layer 150 may have different layer structures according to the desired functions. FIG. 3 is a simplified diagram illustrating a cross section of the fiber structure 100 according to a second embodiment.
The fiber structure 100 according to the second embodiment differs from the fiber structure 100 according to the first embodiment in that the distance between the first fiber layer 110 and the second fiber layer 120, which is the thickness of the first suspension layer 140, differs from the distance between the second fiber layer 120 and the third fiber layer 130, which is the thickness of the second suspension layer 150. When the suspension layers have different thicknesses in this manner, it is possible to cause the suspension layers to have different functions. When the thickness of the first suspension layer 140 is larger than the thickness of the second suspension layer 150 as illustrated in FIG. 3, the first suspension layer 140 has higher impact buffer properties than the second suspension layer 150, in other words, the second suspension layer 150 has higher repulsive properties than the first suspension layer 140. The fiber structure 100 having such a layer structure is preferably used, for example, as a shoe upper material in which the first fiber layer 110 is placed on the inner side and the third fiber layer 130 is placed on the outer side. Furthermore, when the fiber structure 100 includes the suspension layers having different thicknesses in this manner, for example, it is possible to control the impact buffer time during contact with the ground. For example, when the fiber structure 100 in which the second suspension layer 150 having a small thickness has low hardness and the first suspension layer 140 having a large thickness has high hardness is used as a sole material (typically, an insole), it is possible to allow a user to feel the softness of the material for a short time and feel the repulsive force of the material for a long time.
FIG. 4 is a simplified diagram illustrating a cross section of the fiber structure 100 according to a third embodiment. The fiber structure 100 according to the third embodiment differs from the fiber structure 100 according to the first embodiment in that the material of the knitting yarn constituting the first suspension layer 140 differs from the material of the knitting yarn constituting the second suspension layer 150. In the example illustrated in FIG. 4, the knitting yarn constituting the second suspension layer 150 is thicker than the knitting yarn constituting the first suspension layer 140. When the suspension layers are composed of knitting yarns made of different materials in this manner, it is possible to cause the first suspension layer 140 and the second suspension layer 150 to have different functions. Furthermore, other than the thickness, the knitting yarns may differ from each other, for example, in material type (silk yarn, cotton yarn, synthetic fiber, or the like) or in twisted yarn (monofilament, multifilament, or the like).
FIG. 5 is a simplified diagram illustrating a cross section of the fiber structure 100 according to a fourth embodiment. The fiber structure 100 according to the fourth embodiment differs from the fiber structure 100 according to the first embodiment in that the air permeability of the first suspension layer 140 differs from the air permeability of the second suspension layer 150. In other words, the intervals in the plane direction at which the yarn of the first suspension layer 140 is stretched between the first fiber layer 110 and the second fiber layer 120 differs from the intervals in the plane direction at which the yarn of the second suspension layer 150 is stretched between the second fiber layer 120 and the third fiber layer 130. In the example illustrated in FIG. 5, the second suspension layer 150 is more roughly knitted than the first suspension layer 140, and thus has a higher air permeability than the first suspension layer 140. In such a layer structure, the second suspension layer 150 has higher impact buffer properties than the first suspension layer 140, and the first suspension layer 140 has higher repulsive properties than the second suspension layer 150.
FIG. 6 is a simplified diagram illustrating a cross section of the fiber structure 100 according to a fifth embodiment. The fiber structure 100 according to the fifth embodiment differs from the fiber structure 100 according to the first embodiment mainly in that the second suspension layer 150 has a first region 101 and a second region 102 that are partitioned from each other in the plane direction and the layer structure in the first region 101 differs from the layer structure in the second region 102.
In the example illustrated in FIG. 6, in the process of forming the second suspension layer 150, the intervals in the plane direction at which the yarn of the second suspension layer 150 is stretched between the second fiber layer 120 and the third fiber layer 130 is changed at the boundary between the first region 101 and the second region 102, and the second suspension layer 150 is more roughly knitted in the second region 102 than in the first region 101; thus, the second suspension layer 150 has a higher air permeability in the second region 102 than in the first region 101. When the second suspension layer 150 has different layer structures in regions partitioned from each other in the plane direction in this manner, for example, it is possible to provide an upper in which a heel portion has high repulsive properties and an instep portion has high impact buffer properties. Furthermore, it is possible to provide an upper in which a heel portion has high repulsive properties and a portion around the ankle has high impact buffer properties.
The layer structures in the first region 101 and the second region 102 may differ from each other in material or thickness as described above. Furthermore, the second suspension layer 150 may not necessarily be partitioned into the first region 101 and the second region 102 in the plane direction, and the second suspension layer 150 may be partitioned into three or more regions in the plane direction.
In the example illustrated un FIG. 6, the second suspension layer 150 is partitioned into the first region 101 and the second region 102 to have different layer structures in the regions; however, the first suspension layer 140 may be partitioned into the first region 101 and the second region 102 to have different layer structures in the regions. Alternatively, each of the first suspension layer 140 and the second suspension layer 150 may be partitioned into the first region 101 and the second region 102 to have different layer structures in the regions, and in that case, the first suspension layer 140 and the second suspension layer 150 may be partitioned into the first region 101 and the second region 102 in the plane direction in different manners.
It is possible to combine characteristics of the layer structures according to the second embodiment to the fifth embodiment described above. For example, when the characteristics of the layer structure according to the second embodiment are combined with the characteristics of the layer structure according to the third embodiment, it is possible to cause the first suspension layer 140 and the second suspension layer 150 to have different thicknesses and be composed of knitting yarns made of different materials.
Next, a method of manufacturing the fiber structure 100 will be described. In the present embodiment, a first manufacturing method and a second manufacturing method in which the second fiber layer 120 is formed differently will be described.
FIG. 7 is a simplified diagram illustrating a first manufacturing method of the fiber structure 100. In FIG. 7, the hollow arrow indicates the direction (X-axis positive direction) in which the fiber structure 100 is manufactured. For simplification, in this case, each of the first suspension layer 140 and the second suspension layer 150 is indicated by two knitting yarns (a first yarn 141 and a second yarn 142 constituting the first suspension layer 140, a third yarn 151 and a fourth yarn 152 constituting the second suspension layer 150). Each of the first suspension layer 140 and the second suspension layer 150 may be composed of a single knitting yarn or three or more knitting yarns.
The first manufacturing method includes a plane layer forming step of forming the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130, and a suspension layer forming step of forming the first suspension layer 140 and the second suspension layer 150, and the plane layer forming step and the suspension layer forming step are simultaneously performed. More specifically, each of the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130 is successively extended in the X-axis positive direction by the plane layer forming step. The first suspension layer 140 is formed by the suspension layer forming step in which the first yarn 141 and the second yarn 142 are phase shifted and stretched between the first fiber layer 110 and the second fiber layer 120 formed slightly earlier by the plane layer forming step, and the first suspension layer 140 is successively extended in the X-axis positive direction. Similarly, the second suspension layer 150 is formed by the suspension layer forming step in which the third yarn 151 and the fourth yarn 152 are phase shifted and stretched between the second fiber layer 120 and the third fiber layer 130 formed slightly earlier by the plane layer forming step, and the second suspension layer 150 is successively extended in the X-axis positive direction.
The first fiber layer 110, the second fiber layer 120, and the first suspension layer 140 may be formed earlier, followed by formation of the third fiber layer 130 and the second suspension layer 150. In that case, the third yarn 151 and the fourth yarn 152 constituting the second suspension layer 150 are stretched between the second fiber layer 120 already formed and the third fiber layer 130 formed slightly earlier than the second suspension layer 150.
FIG. 8 is a simplified diagram illustrating a second manufacturing method of the fiber structure 100. In FIG. 8, the hollow arrow indicates the direction (X-axis positive direction) in which the fiber structure 100 is manufactured. For simplification, in this case, each of the first suspension layer 140 and the second suspension layer 150 is indicated by two knitting yarns (the first yarn 141 and the second yarn 142 constituting the first suspension layer 140, the third yarn 151 and the fourth yarn 152 constituting the second suspension layer 150). Each of the first suspension layer 140 and the second suspension layer 150 may be composed of a single knitting yarn or three or more knitting yarns.
The second manufacturing method includes an outer layer forming step of forming the first fiber layer 110 and the third fiber layer 130, and an inner layer forming step of forming the second fiber layer 120 composed of at least two or more knitting yarns in the plane direction parallel to the first fiber layer 110 and the third fiber layer 130 by causing, between the first fiber layer 110 and the third fiber layer 130, the first yarn 141 and the second yarn 142 drawn from the first fiber layer 110 toward the third fiber layer 130 to respectively cross the third yarn 151 and the fourth yarn 152 drawn from the third fiber layer 130 toward the first fiber layer 110, forming the first suspension layer 140 by causing the first yarn 141 and the second yarn 142 to reach the second fiber layer 120 and return to the first fiber layer 110, and forming the second suspension layer 150 by causing the third yarn 151 and the fourth yarn 152 to reach the second fiber layer 120 and return to the third fiber layer 130, and the outer layer forming step and the inner layer forming step are simultaneously performed. In this case, the first fiber layer 110 and the third fiber layer 130 are referred to as outer layers, and the first suspension layer 140, the second suspension layer, and the second fiber layer are referred to as inner layers.
More specifically, each of the first fiber layer 110 and the third fiber layer 130 is successively extended in the X-axis positive direction by the outer layer forming step. The first yarn 141 and the second yarn 142 phase shifted and interlaced with the first fiber layer 110 formed slightly earlier by the outer layer forming step are drawn toward the third fiber layer 130. Similarly, the third yarn 151 and the fourth yarn 152 phase shifted and interlaced with the third fiber layer 130 formed slightly earlier by the outer layer forming step are drawn toward the first fiber layer 110. The first yarn 141 and the second yarn 142 cross the third yarn 151 and the fourth yarn 152 between the first fiber layer 110 and the third fiber layer 130 (e.g., in an intermediate portion between the first fiber layer 110 and the third fiber layer 130). In the present embodiment, the first yarn 141 crosses the third yarn 151, and the second yarn 142 crosses the fourth yarn 152. The first yarn 141 may cross the fourth yarn 152, or may cross both the third yarn 151 and the fourth yarn 152. Alternatively, the first yarn 141, the second yarn 142, the third yarn 151, and the fourth yarn 152 may cross each other.
The yarns crossing each other are slightly drawn in the plane direction to form the second fiber layer 120 between the first fiber layer 110 and the third fiber layer 130. At this time, the first yarn 141 and the second yarn 142 reach a surface of the second fiber layer facing the third fiber layer 130 and are folded back toward the first fiber layer 110 to form the first suspension layer 140. Similarly, the third yarn 151 and the fourth yarn 152 reach a surface of the second fiber layer facing the first fiber layer 110 and are folded back toward the third fiber layer 130 to form the second suspension layer 150.
Thus, the fiber structure 100 is manufactured by repeatedly performing the inner layer forming step of forming the inner layers synchronously with the outer layer forming step described above. The second fiber layer 120 may not necessarily be composed of the first yarn 141 and the second yarn 142 constituting the first suspension layer 140 and the third yarn 151 and the fourth yarn 152 constituting the second suspension layer 150. The second fiber layer 120 may be more densely formed, or a splicing yarn may be knitted with yarns to make it easy for the yarns to be interlaced with each other. When the first suspension layer 140 is composed of a single yarn and the second suspension layer 150 is composed of a single yarn, it is possible to form the second fiber layer 120 using two yarns.
Next, modifications of the fiber structure 100 will be described. FIG. 9 is a diagram illustrating an example of the fiber structure 100 having a multilayer structure including more layers.
The layer structures of the fiber structure 100 described above include three fiber layers (the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130), and two suspension layers (the first suspension layer 140 and the second suspension layer 150) formed between the fiber layers. However, the fiber structure 100 may have a layer structure including more layers to have more various functions in the layer direction.
The fiber structure 100 illustrated in FIG. 9 further includes a fourth fiber layer 160 and a fifth fiber layer 170 in addition to the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130, and includes a third suspension layer 180 similar to the first suspension layer 140 between the third fiber layer 130 and the fourth fiber layer 160, and a fourth suspension layer 190 similar to the second suspension layer 150 between the fourth fiber layer 160 and the fifth fiber layer 170. The layer structures of the suspension layers may be designed according to the desired functions, and the suspension layers may have different layer structures. Furthermore, the fiber layers may also have different structures, and for example, the outer layers may have a particularly large thickness.
FIG. 10 is a diagram illustrating an example of the fiber structure 100 part of which has a multilayer structure. The fiber structure 100 has the multilayer structure described above in a multilayer region 103. A transition region 104 is an intermediate region between the multilayer region 103 and a single-layer region 105, and is a region in which the multilayer structure is changed to a single-layer structure in a stepwise manner. In the single-layer region 105, the fiber structure 100 does not include the first suspension layer 140 or the second suspension layer 150 in the multilayer region 103, and includes, as a single-layer structure, a fiber layer 210 in which the first fiber layer 110, the second fiber layer 120, and the third fiber layer 130 are integrated. The fiber structure 100 having a single-layer structure and a multilayer structure in this manner can be preferably adopted, for example, in an application including both a portion to which a function in the layer direction is to be provided and a portion in which the thickness is to be small.
FIG. 11 is a front view illustrating an example in which the fiber structure 100 is used in portions of a clothing item 200. FIG. 12 is a rear view illustrating an example in which the fiber structure 100 is used in portions of the clothing item 200. When the fiber structure 100 is used in the clothing item 200, as illustrated in FIGs. 11 and 12, the fiber structure 100 can be placed in specific portions 243 of the clothing item 200. For example, in the structures 100 used in the buttocks or shins of the clothing item 200, a suspension layer on the inner side (on the side closer to the body) preferably has lower hardness than a suspension layer on the outer side. Furthermore, for example, in the structures 100 used in the chest or hip joints of the clothing item 200, a suspension layer on the inner side preferably has lower stretching stress and flexural rigidity than a suspension layer on the outer side. Needless to say, fiber structures 100 selected according to the characteristics of portions of the clothing item 200 may be connected together to constitute the entire clothing item 200.
In the embodiments described above, the fiber structure 100 is assumed to be mainly adopted in a shoe upper and a clothing item; however, the application to which the fiber structure 100 is applied is not limited to these. The fiber structure 100 can be preferably adopted in any application required to have various functions in the layer direction. The fiber structure 100 can be preferably adopted, for example, in shoe sponges, tongues, insoles, and sock linings. In addition, the fiber structure 100 can also be preferably adopted in bags, headwear items, fashion accessories, and other fiber materials.

Claims

A fiber structure at least part of which has a layer structure including
a first fiber layer, a second fiber layer, and a third fiber layer that are arranged parallel to one another,

a first suspension layer that is composed of a weaving yarn or a knitting yarn stretched between the first fiber layer and the second fiber layer, and

a second suspension layer that is composed of a weaving yarn or a knitting yarn stretched between the second fiber layer and the third fiber layer.
The fiber structure according to claim 1, wherein
each of the first fiber layer, the second fiber layer, and the third fiber layer is a knitted layer or a woven layer.
The fiber structure according to claim 1, wherein
the first suspension layer has a higher air permeability than either the first fiber layer or the second fiber layer, and

the second suspension layer has a higher air permeability than either the second fiber layer or the third fiber layer.
The fiber structure according to claim 1, wherein
a layer structure of the first suspension layer differs from a layer structure of the second suspension layer.
The fiber structure according to claim 4, wherein
a thickness of the first suspension layer differs from a thickness of the second suspension layer.
The fiber structure according to claim 4, wherein
a material of the weaving yarn or the knitting yarn of the first suspension layer differs from a material of the weaving yarn or the knitting yarn of the second suspension layer.
The fiber structure according to claim 4, wherein
an air permeability of the first suspension layer differs from an air permeability of the second suspension layer.
The fiber structure according to claim 1, wherein
at least one of the first suspension layer and the second suspension layer has a first region and a second region partitioned from each other in a plane direction, and

a layer structure in the first region differs from a layer structure in the second region.
The fiber structure according to claim 1, wherein
the weaving yarn or the knitting yarn of the first suspension layer reaches a surface of the second fiber layer facing the third fiber layer and is folded back, and

the weaving yarn or the knitting yarn of the second suspension layer reaches a surface of the second fiber layer facing the first fiber layer and is folded back.
The fiber structure according to claim 9, wherein
the second fiber layer includes a folded portion of each of the weaving yarn or the knitting yarn of the first suspension layer and the weaving yarn or the knitting yarn of the second suspension layer.
The fiber structure according to claim 9, wherein
the second fiber layer is composed of the weaving yarn or the knitting yarn of the first suspension layer and the weaving yarn or the knitting yarn of the second suspension layer.
A shoe that adopts the fiber structure according to any one of claims 1 to 11.
A clothing item that adopts the fiber structure according to any one of claims 1 to 11.
A bag that adopts the fiber structure according to any one of claims 1 to 11.
A method of manufacturing a fiber structure, the method comprising:
a plane layer forming step of forming a first fiber layer, a second fiber layer, and a third fiber layer; and

a suspension layer forming step of forming a first suspension layer by stretching a weaving yarn or a knitting yarn between the first fiber layer and the second fiber layer and forming a second suspension layer by stretching a weaving yarn or a knitting yarn between the second fiber layer and the third fiber layer.
A method of manufacturing a fiber structure, the method comprising:
an outer layer forming step of forming a first fiber layer and a third fiber layer; and

an inner layer forming step of forming a second fiber layer by causing, between the first fiber layer and the third fiber layer, a weaving yarn or a knitting yarn drawn from the first fiber layer toward the third fiber layer to cross a weaving yarn or a knitting yarn drawn from the third fiber layer toward the first fiber layer, forming a first suspension layer by causing the weaving yarn or the knitting yarn drawn from the first fiber layer to reach the second fiber layer and return to the first fiber layer, and forming a second suspension layer by causing the weaving yarn or the knitting yarn drawn from the third fiber layer to reach the second fiber layer and return to the third fiber layer.