Fiber Structure, Shoe, Clothing Item, Bag, and Method of Manufacturing Fiber Structure

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

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

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).

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.

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.

is a schematic perspective view illustrating a portion cut from a fiber structureaccording to the present embodiment. The fiber structureaccording to the present embodiment includes a first fiber layer, a second fiber layer, and a third fiber layerthat are arranged parallel to one another, a first suspension layerthat is composed of a yarn stretched between the first fiber layerand the second fiber layer, and a second suspension layerthat is composed of a yarn stretched between the second fiber layerand the third fiber layer. Each of the first fiber layer, the second fiber layer, and the third fiber layermay 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 layerand the second suspension layermay 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 layerformed between the first fiber layerand the second fiber layerhas a higher air permeability than each of the first fiber layerand the second fiber layer. In other words, the first fiber layerand the second fiber layerare more densely knitted than the first suspension layer. 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 layerformed between the second fiber layerand the third fiber layerhas a higher air permeability than each of the second fiber layerand the third fiber layer. In other words, the second fiber layerand the third fiber layerare more densely knitted than the second suspension layer. In such a layer structure, the first fiber layer, the second fiber layer, and the third fiber layerarranged parallel to one another mainly have the function of maintaining the strength in the plane direction, and the first suspension layerand the second suspension layermainly 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, the second fiber layer, and the third fiber layerarranged 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 structurehaving various characteristics can be obtained by adjusting the layer structures of the first suspension layerand the second suspension layer. Thus, the layer structures of the first suspension layerand the second suspension layerwill be described through embodiments of the fiber structure.

is a simplified diagram illustrating a cross section of the fiber structureaccording to a first embodiment. In the first embodiment, the first suspension layerand the second suspension layerhave the same layer structure. That is, the distance between the first fiber layerand the second fiber layer, which is the thickness of the first suspension layer, is the same as the distance between the second fiber layerand the third fiber layer, which is the thickness of the second suspension layer, and the first suspension layerand the second suspension layerare 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 laver.

Needless to say, the first suspension layerand the second suspension layermay have different layer structures according to the desired functions.is a simplified diagram illustrating a cross section of the fiber structureaccording to a second embodiment.

The fiber structureaccording to the second embodiment differs from the fiber structureaccording to the first embodiment in that the distance between the first fiber layerand the second fiber layer, which is the thickness of the first suspension layer, differs from the distance between the second fiber layerand the third fiber layer, which is the thickness of the second suspension layer. 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 layeris larger than the thickness of the second suspension layeras illustrated in, the first suspension layerhas higher impact buffer properties than the second suspension layer, in other words, the second suspension layerhas higher repulsive properties than the first suspension layer. The fiber structurehaving such a layer structure is preferably used, for example, as a shoe upper material in which the first fiber layeris placed on the inner side and the third fiber layeris placed on the outer side. Furthermore, when the fiber structureincludes 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 structurein which the second suspension layerhaving a small thickness has low hardness and the first suspension layerhaving 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.

is a simplified diagram illustrating a cross section of the fiber structureaccording to a third embodiment. The fiber structureaccording to the third embodiment differs from the fiber structureaccording to the first embodiment in that the material of the knitting yarn constituting the first suspension layerdiffers from the material of the knitting yarn constituting the second suspension layer. In the example illustrated in, the knitting yarn constituting the second suspension layeris thicker than the knitting yarn constituting the first suspension layer. When the suspension layers are composed of knitting yarns made of different materials in this manner, it is possible to cause the first suspension layerand the second suspension layerto 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).

is a simplified diagram illustrating a cross section of the fiber structureaccording to a fourth embodiment. The fiber structureaccording to the fourth embodiment differs from the fiber structureaccording to the first embodiment in that the air permeability of the first suspension layerdiffers from the air permeability of the second suspension layer. In other words, the intervals in the plane direction at which the yarn of the first suspension layeris stretched between the first fiber layerand the second fiber layerdiffers from the intervals in the plane direction at which the yarn of the second suspension layeris stretched between the second fiber layerand the third fiber layer. In the example illustrated in, the second suspension layeris more roughly knitted than the first suspension layer, and thus has a higher air permeability than the first suspension layer. In such a layer structure, the second suspension layerhas higher impact buffer properties than the first suspension layer, and the first suspension layerhas higher repulsive properties than the second suspension layer.

is a simplified diagram illustrating a cross section of the fiber structureaccording to a fifth embodiment. The fiber structureaccording to the fifth embodiment differs from the fiber structureaccording to the first embodiment mainly in that the second suspension layerhas a first regionand a second regionthat are partitioned from each other in the plane direction and the layer structure in the first regiondiffers from the layer structure in the second region.

In the example illustrated in, in the process of forming the second suspension layer, the intervals in the plane direction at which the yarn of the second suspension layeris stretched between the second fiber layerand the third fiber layeris changed at the boundary between the first regionand the second region, and the second suspension layeris more roughly knitted in the second regionthan in the first region; thus, the second suspension layerhas a higher air permeability in the second regionthan in the first region. When the second suspension layerhas 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 regionand the second regionmay differ from each other in material or thickness as described above. Furthermore, the second suspension layermay not necessarily be partitioned into the first regionand the second regionin the plane direction, and the second suspension layermay be partitioned into three or more regions in the plane direction.

In the example illustrated un, the second suspension layeris partitioned into the first regionand the second regionto have different layer structures in the regions; however, the first suspension layermay be partitioned into the first regionand the second regionto have different layer structures in the regions. Alternatively, each of the first suspension layerand the second suspension layermay be partitioned into the first regionand the second regionto have different layer structures in the regions, and in that case, the first suspension layerand the second suspension layermay be partitioned into the first regionand the second regionin 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 layerand the second suspension layerto have different thicknesses and be composed of knitting yarns made of different materials.

Next, a method of manufacturing the fiber structurewill be described. In the present embodiment, a first manufacturing method and a second manufacturing method in which the second fiber layeris formed differently will be described.

is a simplified diagram illustrating a first manufacturing method of the fiber structure. In, the hollow arrow indicates the direction (X-axis positive direction) in which the fiber structureis manufactured. For simplification, in this case, each of the first suspension layerand the second suspension layeris indicated by two knitting yarns (a first yarnand a second yarnconstituting the first suspension layer, a third yarnand a fourth yarnconstituting the second suspension layer). Each of the first suspension layerand the second suspension layermay 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. the second fiber layer, and the third fiber layer, and a suspension layer forming step of forming the first suspension layerand the second suspension layer, and the plane layer forming step and the suspension layer forming step are simultaneously performed. More specifically, each of the first fiber layer, the second fiber layer, and the third fiber layeris successively extended in the X-axis positive direction by the plane layer forming step. The first suspension layeris formed by the suspension layer forming step in which the first yarnand the second yarnare phase shifted and stretched between the first fiber layerand the second fiber layerformed slightly earlier by the plane layer forming step, and the first suspension layeris successively extended in the X-axis positive direction. Similarly, the second suspension layeris formed by the suspension layer forming step in which the third yarnand the fourth yarnare phase shifted and stretched between the second fiber layerand the third fiber layerformed slightly earlier by the plane layer forming step, and the second suspension layeris successively extended in the X-axis positive direction.

The first fiber layer, the second fiber layer, and the first suspension layermay be formed earlier, followed by formation of the third fiber layerand the second suspension layer. In that case, the third yarnand the fourth yarnconstituting the second suspension layerare stretched between the second fiber layeralready formed and the third fiber layerformed slightly earlier than the second suspension layer.

is a simplified diagram illustrating a second manufacturing method of the fiber structure. In, the hollow arrow indicates the direction (X-axis positive direction) in which the fiber structureis manufactured. For simplification, in this case, each of the first suspension layerand the second suspension layeris indicated by two knitting yarns (the first yarnand the second yarnconstituting the first suspension layer, the third yarnand the fourth yarnconstituting the second suspension layer). Each of the first suspension layerand the second suspension layermay 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 layerand the third fiber layer, and an inner layer forming step of forming the second fiber layercomposed of at least two or more knitting yarns in the plane direction parallel to the first fiber layerand the third fiber layerby causing, between the first fiber layerand the third fiber layer, the first yarnand the second yarndrawn from the first fiber layertoward the third fiber layerto respectively cross the third yarnand the fourth yarndrawn from the third fiber layertoward the first fiber layer, forming the first suspension layerby causing the first yarnand the second yarnto reach the second fiber layerand return to the first fiber layer, and forming the second suspension layerby causing the third yarnand the fourth yarnto reach the second fiber layerand return to the third fiber layer, and the outer layer forming step and the inner layer forming step are simultaneously performed. In this case, the first fiber layerand the third fiber layerare referred to as outer layers, and the first suspension layer, the second suspension layer, and the second fiber layer are referred to as inner layers.

More specifically, each of the first fiber layerand the third fiber layeris successively extended in the X-axis positive direction by the outer layer forming step. The first yarnand the second yarnphase shifted and interlaced with the first fiber layerformed slightly earlier by the outer layer forming step are drawn toward the third fiber layer. Similarly, the third yarnand the fourth yarnphase shifted and interlaced with the third fiber layerformed slightly earlier by the outer layer forming step are drawn toward the first fiber layer. The first yarnand the second yarncross the third yarnand the fourth yarnbetween the first fiber layerand the third fiber layer(e.g., in an intermediate portion between the first fiber layerand the third fiber layer). In the present embodiment, the first yarncrosses the third yarn, and the second yarncrosses the fourth yarn. The first yarnmay cross the fourth yarn, or may cross both the third yarnand the fourth yarn. Alternatively, the first yarn, the second yarn, the third yarn, and the fourth yarnmay cross each other.

The yarns crossing each other are slightly drawn in the plane direction to form the second fiber layerbetween the first fiber layerand the third fiber layer. At this time, the first yarnand the second yarnreach a surface of the second fiber layer facing the third fiber layerand are folded back toward the first fiber layerto form the first suspension layer. Similarly, the third yarnand the fourth yarnreach a surface of the second fiber layer facing the first fiber layerand are folded back toward the third fiber layerto form the second suspension layer.

Thus, the fiber structureis 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 layermay not necessarily be composed of the first yarnand the second yarnconstituting the first suspension layerand the third yarnand the fourth yarnconstituting the second suspension layer. The second fiber layermay 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 layeris composed of a single yarn and the second suspension layeris composed of a single yarn, it is possible to form the second fiber layerusing two yarns.

Next, modifications of the fiber structurewill be described.is a diagram illustrating an example of the fiber structurehaving a multilayer structure including more layers.

The layer structures of the fiber structuredescribed above include three fiber layers (the first fiber layer, the second fiber layer, and the third fiber layer), and two suspension layers (the first suspension layerand the second suspension layer) formed between the fiber layers. However, the fiber structuremay have a layer structure including more layers to have more various functions in the layer direction.

The fiber structureillustrated infurther includes a fourth fiber layerand a fifth fiber layerin addition to the first fiber layer, the second fiber layer, and the third fiber layer, and includes a third suspension layersimilar to the first suspension layerbetween the third fiber layerand the fourth fiber layer, and a fourth suspension layersimilar to the second suspension layerbetween the fourth fiber layerand the fifth fiber layer. 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.

is a diagram illustrating an example of the fiber structurepart of which has a multilayer structure. The fiber structurehas the multilayer structure described above in a multilayer region. A transition regionis an intermediate region between the multilayer regionand a single-layer region, 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, the fiber structuredoes not include the first suspension layeror the second suspension layerin the multilayer region, and includes, as a single-layer structure, a fiber layerin which the first fiber layer, the second fiber layer, and the third fiber layerare integrated. The fiber structurehaving 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.

is a front view illustrating an example in which the fiber structureis used in portions of a clothing item.is a rear view illustrating an example in which the fiber structureis used in portions of the clothing item. When the fiber structureis used in the clothing item, as illustrated in, the fiber structurecan be placed in specific portionsof the clothing item. For example, in the structuresused in the buttocks or shins of the clothing item, 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 structuresused in the chest or hip joints of the clothing item, 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 structuresselected according to the characteristics of portions of the clothing itemmay be connected together to constitute the entire clothing item.

In the embodiments described above, the fiber structureis assumed to be mainly adopted in a shoe upper and a clothing item; however, the application to which the fiber structureis applied is not limited to these. The fiber structurecan be preferably adopted in any application required to have various functions in the layer direction. The fiber structurecan be preferably adopted, for example, in shoe sponges, tongues, insoles, and sock linings. In addition, the fiber structurecan also be preferably adopted in bags, headwear items, fashion accessories, and other fiber materials.