Stretchable substrate, stretchable device, and method for manufacturing same

Abstract

A stretchable substrate having a first main surface and a second main surface opposite to each other, the stretchable substrate satisfying any one of: (1) the oxygen atom ratio of at least one of the first main surface and the second main surface as measured by X-ray photoelectron spectroscopy is 5 atom % or more with respect to all atoms; (2) in the first main surface or the second main surface, the arithmetic average surface roughness of the surface measured by a laser microscope is 6 μm or more; (3) at least one of the first main surface and the second main surface has a metal-containing portion; and (4) a metal-containing region is positioned along at least one of the first main surface and the second main surface.

Description

Stretchable substrate, stretchable device, and manufacturing method thereof

[0001] The present invention relates to a stretchable substrate, a stretchable device, and a method for manufacturing the same.

[0002] Conventionally, fluororubber molded articles and elastomers described in Japanese Patent Laid-Open Publication No. 2002-293950 (Patent Document 1) have been used as stretchable substrates. In this document, the fluororubber molded article contains 0.01 to 10 parts by weight of silica powder per 100 parts by weight of fluororubber, has a crosslinked structure formed by a polyamine-based crosslinking agent, and has a wrinkled micro-relief structure on the surface. Such stretchable substrates have appropriate stretchability. Furthermore, the stretchable substrate has a wrinkled micro-relief structure on its surface, resulting in low surface friction resistance.

[0003] Japanese Patent Application Laid-Open No. 2002-293950

[0004] In order to produce a conventional stretchable substrate with low tackiness, it was necessary to separately add a composition containing an inorganic filler such as silica. In such a stretchable substrate, for example, the presence of silica could change the properties of the stretchable substrate. For example, there was concern that the stretchability would change, causing plastic deformation of the stretchable substrate, specifically, increasing permanent set.

[0005] An object of the present invention is to provide a stretchable substrate, a stretchable device, and methods for manufacturing the same, which can suppress permanent distortion and self-adhesion on the surface.

[0006] In order to solve the above-mentioned problems, a stretchable substrate in one aspect of the present disclosure is a stretchable substrate having a first main surface and a second main surface facing each other, wherein the stretchable substrate has any one of the following: (1) an oxygen atomic ratio of at least one of the first main surface and the second main surface measured by X-ray photoelectron spectroscopy is 5 atomic % or more relative to all atoms; (2) an arithmetic mean surface roughness of the first main surface or the second main surface measured by a laser microscope is 6 μm or more; (3) at least one of the first main surface and the second main surface has a metal-containing portion containing metal atoms; and (4) a metal-containing region containing metal atoms is located along at least one of the first main surface and the second main surface.

[0007] The above-described structure provides a surface-modified stretchable substrate, which can suppress tackiness and self-adhesion of the stretchable substrate.

[0008] In one aspect of the present disclosure, the stretchable substrate has a first main surface and a second main surface facing each other, and the oxygen atomic ratio of at least one of the first main surface and the second main surface measured by X-ray photoelectron spectroscopy is 5 atomic % or more relative to all atoms.

[0009] The above-described structure provides a surface-modified stretchable substrate, which can suppress tackiness and self-adhesion of the stretchable substrate.

[0010] In one aspect of the present disclosure, the stretchable substrate has a first main surface and a second main surface that face each other, and the arithmetic mean surface roughness of the first main surface or the second main surface measured with a laser microscope is 6 μm or more.

[0011] The above-described structure provides a surface-modified stretchable substrate, which can prevent the stretchable substrate from self-adhesion.

[0012] A stretchable substrate according to one aspect of the present disclosure has a first main surface and a second main surface facing each other, and at least one of the first main surface and the second main surface has a metal-containing portion that contains metal atoms.

[0013] By providing a metal-containing portion on at least one of the first and second main surfaces of the stretchable substrate, molecular diffusion that causes autoadhesion can be suppressed, thereby suppressing autoadhesion of the stretchable substrate. Here, the metal-containing portion refers to a portion that contains a metal-containing compound.

[0014] A stretchable substrate having a first main surface and a second main surface opposed to each other, wherein a metal-containing portion containing metal atoms is located along at least one of the first main surface and the second main surface.

[0015] The above-described structure suppresses molecular diffusion that causes self-adhesion, thereby suppressing self-adhesion of the stretchable substrate. Furthermore, the metal-containing portion adheres to substrates other than the stretchable substrate, improving the adhesion between the stretchable substrate and the other substrates.

[0016] A stretchable device according to one aspect of the present disclosure includes the stretchable substrate of the present disclosure and wiring disposed on the first main surface of the stretchable substrate.

[0017] By having the above-described configuration, it is possible to provide a stretchable device in which tackiness and self-adhesion are suppressed.

[0018] The stretchable device in one aspect of the present disclosure further comprises a protective layer.

[0019] With the above configuration, the wiring can be protected.

[0020] A method for producing a stretchable substrate in one aspect of the present disclosure includes: a preparation step of preparing a substrate; and an ozone treatment step of performing ozone treatment on at least one of a first main surface of the substrate and a second main surface located opposite to the first main surface.

[0021] By carrying out the above steps, a stretchable substrate having oxygen atoms can be formed. As a result, the surface of the base material is modified, and tackiness and self-adhesion of the stretchable substrate can be suppressed.

[0022] A method for manufacturing a stretchable device according to one aspect of the present disclosure includes: a preparation step of preparing a substrate having a first main surface and a second main surface facing each other; an arrangement step of arranging wiring on the first main surface of the substrate; and an ozone treatment step of performing ozone treatment on at least one of the first main surface and the second main surface after the arrangement step.

[0023] By carrying out the above steps, a stretchable device in which self-adhesion is suppressed can be formed. In addition, the ozone treatment can be carried out in a state in which wiring is present, which simplifies the manufacturing method.

[0024] A method for manufacturing a stretchable device according to one aspect of the present disclosure includes: a preparation step of preparing a substrate having a first main surface and a second main surface facing each other; an arrangement step of arranging wiring on the first main surface of the substrate; and an embossing step of embossing at least one of the first main surface and the second main surface after the arrangement step.

[0025] By carrying out the above steps, it is possible to suppress self-adhesion on the surface of the stretchable device. In addition, it is possible to carry out embossing in a state in which wiring is present, thereby simplifying the manufacturing method.

[0026] A method for manufacturing a stretchable device according to one aspect of the present disclosure includes: a preparation step of preparing a first substrate having a first main surface and a second main surface facing each other; and a formation step of forming a metal-containing portion on at least the second main surface of the first substrate.

[0027] A method for manufacturing a stretchable device in one aspect of the present disclosure includes: a preparation step of preparing a substrate; and a formation step of forming a metal-containing portion on at least one of a first main surface of the substrate and a second main surface located opposite the first main surface.

[0028] By having a metal-containing portion on at least one of the first main surface and the second main surface of the stretchable substrate, molecular diffusion that causes self-adhesion is suppressed, and self-adhesion of the stretchable device can be suppressed.

[0029] A method for manufacturing a stretchable device in one aspect of the present disclosure includes: a preparation step of preparing a first substrate having a first main surface and a second main surface facing each other; an arrangement step of arranging wiring on the first main surface of the first substrate; and a formation step of forming a metal-containing portion on at least the second main surface of the first substrate after the arrangement step.

[0030] By carrying out the above steps, a stretchable device in which self-adhesion is suppressed can be formed.

[0031] According to the present disclosure, it is possible to provide a stretchable substrate, a stretchable device, and methods for manufacturing the same that can suppress self-adhesion on the surface while suppressing permanent distortion.

[0032] 1. A partial top view of a stretchable device of a first embodiment. A cross-sectional view taken along II-II in FIG. 1. An explanatory view illustrating a method for manufacturing a stretchable device of a first embodiment. An explanatory view illustrating a method for manufacturing a stretchable device of a first embodiment. An explanatory view illustrating a method for manufacturing a stretchable device of a first embodiment. A cross-sectional view of a stretchable device of a second embodiment. A schematic view showing a first main surface of a stretchable substrate of a second embodiment. A schematic view showing a sheet material for embossing process for forming the first main surface of a stretchable substrate of a second embodiment. An explanatory view illustrating a method for manufacturing a stretchable device of a second embodiment. An explanatory view illustrating a method for manufacturing a stretchable device of a second embodiment. An explanatory view illustrating a method for manufacturing a stretchable device of a second embodiment. An explanatory view illustrating a method for manufacturing a stretchable device of a second embodiment. A schematic view of a first modified example showing the first main surface of a stretchable substrate of a second embodiment. A schematic view showing a sheet material for embossing process of a first modified example for forming the first main surface of a stretchable substrate of a second embodiment. A schematic view showing a modified example of a sheet material for embossing process of a first modified example. 1. A cross-sectional view of a stretchable device of a third embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a third embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a third embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a third embodiment. A cross-sectional view of modified example 1 of the third embodiment. A cross-sectional view of modified example 2 of the third embodiment. A cross-sectional view of a stretchable device of a fourth embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a fourth embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a fourth embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a fourth embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a fourth embodiment. An explanatory diagram illustrating a manufacturing method of a stretchable device of a fourth embodiment. An explanatory diagram illustrating a hard phase portion of the stretchable substrate of an example 19. An explanatory diagram illustrating a measurement method for a peel test. A measurement diagram illustrating the relationship between the moving distance and peel force in a peel test in example 40 and comparative example 5. A measurement diagram illustrating the relationship between the press temperature and the peel strength in a peel test.

[0033] Hereinafter, a stretchable device according to one aspect of the present disclosure will be described in detail with reference to the illustrated embodiments. Note that the drawings include some schematic views and may not reflect actual dimensions or proportions.

[0034] The stretchable device of the present disclosure has a stretchable substrate and wiring provided on a first main surface of the stretchable substrate.

[0035] The stretchable substrate has a first main surface and a second main surface facing each other, and the stretchable substrate has any one of the following: (1) the oxygen atomic ratio of at least one of the first main surface and the second main surface measured by X-ray photoelectron spectroscopy is 5 atomic % or more relative to all atoms, (2) the arithmetic mean surface roughness of the first main surface or the second main surface measured by a laser microscope is 6 μm or more, (3) at least one of the first main surface and the second main surface has a metal-containing portion containing metal atoms, and (4) a metal-containing region containing metal atoms is located along at least one of the first main surface and the second main surface. Each of (1) to (4) will be described below as a specific embodiment.

[0036] <First embodiment> [Configuration] The structure of a stretchable device 100 according to a first embodiment will be described with reference to Fig. 1 and Fig. 2. Fig. 1 is a partial top view of the stretchable device 100. Fig. 2 is a cross-sectional view of the stretchable device 100 taken along the line II-II in Fig. 1.

[0037] As shown in FIGS. 1 and 2, the stretchable device 100 has a stretchable substrate 1 and wiring 2 provided on a first main surface 1 a of the stretchable substrate 1 .

[0038] The shape of the stretchable device 100 is not particularly limited. In this specification, a structure in which one stretchable substrate is connected to the stretchable device 100 is described as an example, but two or more stretchable substrates may be connected to the stretchable device 100. Furthermore, the wiring 2 is not limited to the arrangement shown in FIG. 1 , and the extension direction is also not limited. Specifically, the longitudinal direction of the stretchable substrate 1 and the extension direction of the wiring 2 do not have to coincide, and the wiring 2 does not have to extend in one direction. Furthermore, the number of wirings 2 is not particularly limited, and may be one or more.

[0039] Furthermore, "above" in this specification does not have to coincide with the up and down when the stretchable device 100 is in use. More specifically, "above the main surface of the stretchable substrate 1" does not refer to an absolute direction such as vertically upward as defined by the direction of gravity, but rather refers to a direction toward the outside of the inside and outside with the main surface of the stretchable substrate 1 as a boundary, based on the main surface of the stretchable substrate 1. Furthermore, "above" with respect to a certain element includes not only an above position separated from the element, i.e., an above position via another object on the element or an above position spaced apart, but also a position directly above the element (on).

[0040] The stretchable substrate 1 has a first main surface 1a and a second main surface 1b located on opposite sides. The stretchable substrate 1 has a stretchable substrate end portion 11 connecting the first main surface 1a and the second main surface 1b. The stretchable substrate 1 is stretchable. The stretchable substrate 1 does not inhibit the expansion and contraction of the wiring 2, and the risk of breakage due to expansion and contraction when the stretchable device 100 is in use can be reduced.

[0041] In the stretchable substrate 1, the oxygen atomic ratio of the first main surface 1a measured by X-ray photoelectron spectroscopy (XPS) is 5 atomic % or more. Preferably, the oxygen atomic ratio is 25 atomic % or less. The above-described configuration modifies the surface of the stretchable substrate. As a result, the tackiness and self-adhesion of the stretchable substrate 1 can be suppressed. It is generally believed that the tackiness and self-adhesion of the stretchable substrate 1 are improved by including oxygen atoms. However, in this embodiment, it has been discovered that the tackiness and self-adhesion can be suppressed by including oxygen atoms. For example, the stretchable substrate 1 can be used in living organisms. As a result, the stretchable substrate 1 is easier to handle, allowing the living organism (e.g., the user) to use the stretchable substrate 1 comfortably. In this embodiment, oxygen atoms are introduced into the first main surface 1a, but they may also be introduced into the second main surface 1b, or into both the first main surface 1a and the second main surface 1b. The above oxygen atomic ratio is a ratio relative to all atoms.

[0042] X-ray photoelectron spectroscopy has high detection sensitivity for the first principal surface 1a, and can therefore be used to determine the ratio of constituent elements on the first principal surface 1a. The ratio of oxygen atoms can be determined by measuring by X-ray photoelectron spectroscopy at a location on the first principal surface 1a where no wiring 2 is present. The location may be provided at the end of the stretchable substrate 1, or may be provided between the stretchable substrate 1 and the wiring. From the viewpoint of suppressing self-adhesion, it is preferable to provide the location at the end of the stretchable substrate 1. The second principal surface 1b may have the same oxygen atomic ratio as the first principal surface 1a. The oxygen concentration ratio of the second principal surface 1b can be measured in the same manner as the oxygen atomic ratio of the first principal surface 1a.

[0043] Preferably, the oxygen atomic ratio in the central portion of the first main surface 1a and the second main surface 1b in the direction perpendicular to the first main surface 1a and the second main surface 1b is 5 atomic % or less, more preferably 1 atomic % or less. For example, by performing ozone treatment, the portion closer to the first main surface 1a or the second main surface 1b is oxidized compared to the central portion, and more oxygen atoms are present on the first main surface 1a or the second main surface 1b side than in the central portion. This configuration can suppress tackiness and self-adhesion of the stretchable substrate 1. Note that the central portion of the first main surface 1a and the second main surface 1b refers to the intersection between the center of the height direction of the first main surface 1a and the center of the width direction of the stretchable substrate, as viewed from the direction perpendicular to the first main surface 1a and the second main surface 1b. The central portion may be approximately the center; for example, a range ±20% away from the center of the first main surface 1a and the second main surface 1b may be measured.

[0044] The oxygen atomic ratio of the first main surface 1 a may be 5 atomic % or more relative to all atoms, and may be 4 atomic % or more higher than the oxygen atomic ratio at the central portions of the first main surface 1 a and the second main surface 1 b in a direction perpendicular to the first main surface 1 a and the second main surface 1 b. For example, the oxygen atomic ratio at the central portions of the first main surface 1 a and the second main surface 1 b in a direction perpendicular to the first main surface 1 a and the second main surface 1 b may be 1 atomic % relative to all atoms, and the oxygen atomic ratio at least of the first main surface 1 a and the second main surface 1 b may be 5 atomic % or more.

[0045] Oxygen atoms can be introduced into the first main surface 1a of the stretchable substrate 1, for example, by performing ozone treatment. The ozone treatment can be performed, for example, using a low-pressure mercury lamp. The ozone treatment can be performed, for example, by setting the ozone concentration to about 10 to 120 ppm and exposing the substrate to ultraviolet (UV) radiation for about 1 to 3 minutes. Oxygen atoms can be introduced into the second main surface 1b in the same way.

[0046] Preferably, it is not necessary to add an inorganic material to the stretchable substrate 1. By having such a configuration, it is possible to suppress permanent distortion and self-adhesion on the surface. The stretchable substrate 1 can be used as a sensor device.

[0047] Examples of the stretchable substrate 1 include a sheet-shaped, film-shaped, or block-shaped substrate made of a stretchable resin material. The resin material is preferably rubber or elastomer. By using such a substrate, the surface of the stretchable substrate 1 is modified, thereby suppressing tackiness and self-adhesion of the stretchable substrate 1.

[0048] The resin material is not particularly limited as long as it is rubber or elastomer, but examples thereof include acrylic resins, styrene resins, urethane resins, etc., and preferably includes at least one resin selected from the group consisting of acrylic resins, styrene resins, and urethane resins. Examples of acrylic resins include acrylic thermoplastic elastomers. Examples of styrene resins include styrene elastomers. Examples of urethane resins include thermoplastic polyurethanes.

[0049] The thickness of the stretchable substrate 1 is not particularly limited, but from the viewpoint of not inhibiting the expansion and contraction of the surface of the living body when attached to the living body, it is preferably 1 mm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. Moreover, the thickness of the stretchable substrate 1 is more preferably 1 μm or more.

[0050] The wiring 2 is provided on the first main surface 1a of the stretchable substrate 1. The wiring 2 is preferably stretchable. Examples of materials for the wiring 2 include a mixture of conductive particles, such as metal powders of Ag, Cu, or Ni, and an elastomer resin such as a silicone resin. The average particle size of the conductive particles is not particularly limited, but is preferably 0.01 μm or more and 10 μm or less. The conductive particles are preferably spherical, but may also be flat or have protrusions to improve stretchability. The elastomer resin preferably contains at least one resin (elastomer resin) selected from the group consisting of epoxy resins, urethane resins, acrylic resins, and silicone resins, which is preferable for ensuring stretchability. The wiring 2 may be provided on the first main surface 1a of the stretchable substrate 1 in a single number, two to three, or five or more.

[0051] The thickness of the wiring 2 is preferably 100 μm or less, more preferably 50 μm or less. The thickness of the stretchable wiring is more preferably 1 μm or more, and may be 5 μm or more. The thickness, width, and length of the wiring 2 are not particularly limited. The wiring 2 does not have to be stretchable.

[0052] (Manufacturing Method) A manufacturing method of the stretchable device 100 will be described with reference to FIGS. 3A, 3B, and 3C.

[0053] First, as shown in FIG. 3A, a substrate 80 having a first surface 80a and a second surface 80b facing each other is prepared (preparation process). As shown in FIG. 3B, a material for the wiring 2 is applied to the first surface 80a of the substrate 80. If the material for the wiring 2 is a conductive paste containing, for example, a mixture of Ag and resin, the conductive paste is applied to the substrate. The application method may be screen printing, gravure printing, or inkjet printing. The conductive paste is then thermally cured to obtain a predetermined resistance value, thereby forming the wiring 2 on the substrate 80 (placement process). As shown in FIG. 3C, a sheet material 3 is prepared. The sheet material 3 covers the areas where ozone treatment is not desired. The sheet material 3 has a first main surface 3a and a second main surface 3b located opposite the first main surface 3a. As shown in FIG. 3C, the second main surface 3b of the sheet material 3 is provided on the upper surface of the wiring 2 opposite the substrate 80. Ozone L is irradiated onto the first main surface 3a of the sheet material 3 and the first surface 80a of the substrate 80 (ozone treatment process). In other words, ozone L is not irradiated onto the wiring 2. This results in the formation of a stretchable device 100. While the sheet material 3 is shown separated from the wiring 2 in FIG. 3C , it may be provided in contact with the wiring 2. In the first embodiment, the wiring 2 is provided on the substrate 80. However, the first embodiment may also include only the substrate 80 without the wiring 2. In the first embodiment, a single substrate 80 is used as the substrate 80, but multiple substrates 80 may be stacked. By performing the above process, a stretchable device 100 with reduced self-adhesion can be formed. Furthermore, ozone treatment can be performed while the wiring 2 is present, simplifying the manufacturing method. After the ozone treatment process, an embossing process may be performed in which an embossing sheet material is pressed against the first surface 80a of the substrate 80.

[0054] (First Modification) In the stretchable substrate 1, in addition to the ratio of oxygen atoms in the first main surface 1a being 5 atomic % or more, the arithmetic mean surface roughness Ra of the first main surface 1a measured by an atomic force microscope (AFM) is 8 nm or more, and may be, for example, 10 nm or more. By having the above configuration, the surface can be roughened, and the tackiness and self-adhesion of the stretchable substrate 1 can be further suppressed. For example, self-adhesion can be reduced not only at room temperature but also under more severe conditions (e.g., 70°C). Specifically, self-adhesion is evaluated in accordance with JIS K 6404-3:1999, in which stretchable substrates 1 are stacked in an environment at 70°C and a weight is placed on the stacked stretchable substrates for measurement. Similar to the measurement in an environment at 70°C, the stretchable substrates 1 are also stacked in an environment at room temperature and a weight is placed on the stacked stretchable substrates for measurement. In this embodiment, the arithmetic mean surface roughness Ra of the first main surface 1a is measured, but the second main surface 1b may also have a similar arithmetic mean surface roughness Ra. The arithmetic mean surface roughness Ra may be, for example, 100 nm or less. Measurement using an atomic force microscope may be performed at the end of the stretchable substrate 1, or may be performed on the stretchable substrate 1 located between the wirings 2. From the viewpoint of suppressing self-adhesion, it is preferable to perform the measurement at the end of the stretchable substrate 1. The second main surface 1b of the stretchable substrate 1 may have the same arithmetic mean surface roughness Ra as the first main surface 1a.

[0055] The first modified example can be obtained, for example, by heat-treating the stretchable substrate 1 obtained in the first embodiment. The heat treatment is not particularly limited, but can be carried out at, for example, 150°C or higher, specifically 160°C or higher. The heat treatment can be carried out, for example, at 180°C or lower. The heat treatment time is not particularly limited, but can be carried out, for example, for 10 minutes to 180 minutes, specifically 20 minutes or longer, and more specifically 30 minutes or longer.

[0056] (Second Modification) In addition to the ratio of oxygen atoms on the surface being 5 atomic % or more, the stretchable substrate 1 may further have a first portion and a second portion whose phases, as measured by an atomic force microscope, are different, with the phase of the first portion being 10° or more ahead of the phase of the second portion, and the surface occupancy of the first portion being 80% or more. That is, the first portion of the stretchable substrate 1 may be harder than the second portion, and the surface occupancy of the harder first portion may be 80% or more of the stretchable substrate 1. The surface occupancy may be, for example, 100% or less of the stretchable substrate 1. This configuration hardens the surface of the stretchable substrate 1, further suppressing the tackiness and self-adhesion of the stretchable substrate 1. For example, the self-adhesion of the stretchable substrate 1 may be reduced not only at room temperature but also under harsher conditions (e.g., 70°C). The "surface occupancy" refers to the ratio of the area occupied by the first portion to the measured area. In this embodiment, the value measured for the surface occupancy of the first main surface 1a is used, but the above value may be the surface occupancy of the second main surface 1b, or the surface occupancy of the first main surface 1a and the second main surface 1b.

[0057] The surface occupancy is measured using an atomic force microscope. Specifically, in a region on the first main surface 1 a where the wiring 2 is not present, a phase image that allows viscoelasticity to be measured is obtained using the atomic force microscope, and the surface occupancy of hard portions where the phase is advanced by 10° or more is determined from the phase image.

[0058] The above-mentioned region may be provided at the end of the stretchable substrate 1, or may be provided on the stretchable substrate 1 between the wirings 2. From the viewpoint of suppressing self-adhesion, it is preferable to provide the above-mentioned region at the end of the stretchable substrate 1.

[0059] The stretchable substrate 1 of the second modified example can be obtained by heat treating a base material 80 having an oxygen atom ratio of 5 atomic % or more. The heat treatment is not particularly limited, but can be carried out at, for example, 70°C or higher, specifically 80°C or higher. The heat treatment can be carried out at, for example, 110°C or lower, specifically 100°C or lower. The heat treatment time is not particularly limited, but can be carried out for, for example, 20 minutes to 120 minutes, specifically 30 minutes to 90 minutes.

[0060] In addition, in the stretchable substrate 1, the ratio of oxygen atoms on the surface measured by X-ray photoelectron spectroscopy may be 5 atomic % or more, the arithmetic mean surface roughness Ra of the surface measured by atomic force microscope may be 8 nm or more, and the surface occupancy rate of hard parts with a phase advance of 10° or more measured by atomic force microscope may be 80% or more.

[0061] Second Embodiment The configuration of a stretchable device 100A according to the second embodiment will be described with reference to FIG. 4 . Unlike the first embodiment, the stretchable substrate 1A of this embodiment has a specific surface arithmetic mean surface roughness. That is, in the second embodiment, the ratio of oxygen atoms on the surface of the stretchable substrate 1A does not need to be 5 atomic % or more. The other configurations are the same as those of the first embodiment, and their description will be omitted. Unless otherwise specified below, the configurations and materials of the stretchable substrate 1A, first main surface 1a, second main surface 1b, and base material 80 may be similar to those of the stretchable substrate 1, first main surface 1a, second main surface 1b, and base material 80 of the first embodiment. The ratio of oxygen atoms on the surface of the stretchable substrate 1A may be 5 atomic % or more.

[0062] As shown in FIG. 4, the arithmetic mean surface roughness Ra' of the surface of the stretchable substrate 1A measured with a laser microscope, i.e., the first principal surface 1a, is 6 μm or more. This configuration modifies the surface of the stretchable substrate 1A. As a result, tackiness and self-adhesion of the stretchable substrate 1A can be suppressed. The arithmetic mean surface roughness Ra' of the first principal surface 1a of the stretchable substrate 1A may be, for example, 10 μm or less. The arithmetic mean surface roughness Ra' can be measured in a region of the first principal surface 1a where no wiring 2 is present. This region may be provided at the edge of the stretchable substrate 1A or in the stretchable substrate 1A between the wirings 2. From the viewpoint of suppressing self-adhesion, it is preferable to provide this region at the edge of the stretchable substrate 1A. The arithmetic mean surface roughness Ra' is measured, for example, using a non-contact film thickness measurement device. The arithmetic mean surface roughness Ra' can also be measured using a contact film thickness measurement device. In this embodiment, the arithmetic mean surface roughness Ra' of the first main surface 1a of the stretchable substrate 1A is described as 6 μm or more, but it may be, for example, 3 μm or more. Also, in this embodiment, the arithmetic mean surface roughness Ra' of the first main surface 1a is described, but not only the arithmetic mean surface roughness Ra' of the first main surface 1a but also the arithmetic mean surface roughness Ra' of the second main surface 1b may be in the above range.

[0063] As shown in Fig. 5A, the first main surface 1a of the stretchable substrate 1A preferably has a lattice shape. The lattice shape is such that a plurality of rectangular first shapes 4A and a plurality of rectangular second shapes 4B are alternately arranged in both the vertical and horizontal directions. The rectangles are, for example, 10 to 100 µm square.

[0064] The first shape 4A has a plurality of convex portions 4a1 and concave groove portions 4a2. The concave groove portions 4a2 extend in the horizontal direction. The concave groove portions 4a2 are arranged parallel to each other in the horizontal direction. The convex portions 4a1 are located between adjacent concave groove portions 4a2. By performing the above process, it is possible to form unevenness on the surface of the stretchable substrate 1A. In other words, by performing the above process, it is possible to increase the surface roughness. It is also possible to harden the surface of the stretchable substrate 1A. As a result, it is possible to further suppress self-adhesion of the stretchable substrate 1A.

[0065] The second shape 4B has a plurality of convex portions 4b1 and concave groove portions 4b2. The concave groove portions 4b2 extend in the horizontal direction. The concave groove portions 4b2 are arranged parallel to each other in the horizontal direction. The convex portions 4b1 are located between adjacent concave groove portions 4b2. With the above configuration, members are less likely to come into contact with the first main surface 1a, and tackiness and self-adhesion of the stretchable substrate 1A can be suppressed. The lattice shape may be provided on only a portion of the first main surface 1a. Furthermore, the lattice shape may be provided not only on the first main surface 1a but also on the second main surface 1b.

[0066] As shown in Fig. 5B, the lattice pattern is formed on the first main surface 1a by embossing using an embossing sheet material 5. In the embossing sheet material 5, warp thread portions 5a1 and weft thread portions 5b1 are alternately woven together. The embossing process includes a heat and pressure treatment step.

[0067] A method for manufacturing the stretchable device 100A will be described with reference to FIGS. 6A, 6B, and 6C.

[0068] First, as shown in FIG. 6A , a substrate 80 is prepared (preparation step). As shown in FIG. 6B , a material for the wiring 2 is applied to the first surface 80a of the substrate 80 (placement step). As shown in FIG. 6C , an embossing sheet material 5 having a surface pattern is provided on the upper surface of the wiring 2 opposite the substrate 80. The embossing sheet material 5 does not contact the wiring 2. The embossing sheet material 5 is pressed against the first surface 80a of the substrate 80. This transfers the shape of the embossing sheet material 5 to the first surface 80a, forming the first main surface 1a (embossing step). Note that the embossing sheet material 5 may only partially cover the area of ​​the first surface 80a other than the wiring 2. By performing the above steps, auto-adhesion on the surface of the stretchable device 100A can be suppressed. Furthermore, embossing can be performed while the wiring 2 is present, simplifying the manufacturing method.

[0069] In this embodiment, the embossing sheet material 5 is provided so as not to overlap the wiring 2, but in another embodiment, a protective layer may be provided to protect the wiring 2, and the embossing sheet material 5 may be pressed against the base material 80 and the protective layer. Also, embossing may be performed on the surface of the base material 80 opposite to the wiring 2.

[0070] (First Modification) The first main surface 1a of the stretchable substrate 1A has a shape shown in FIG. 7A instead of the lattice shape shown in FIG. 5A.

[0071] As shown in FIG. 7A , the first main surface 1a has a plurality of first recesses 4c1 and a plurality of second recesses 4c2 perpendicular to the first recesses 4c1. The angle θ between the extension direction of the first recesses 4c1 and an orthogonal line D perpendicular to the longitudinal direction of the stretchable substrate 1A is approximately 45°. The angle between the extension direction of the second recesses 4c2 and an orthogonal line D perpendicular to the longitudinal direction of the stretchable substrate 1A is approximately −45°. One first recess 4c1, the other first recess 4c1 adjacent to the first recess 4c1, one second recess 4c2, and the other second recess 4c2 adjacent to the second recess 4c2 form a rectangle 4c3. The above shape may be provided only on a portion of the first main surface 1a. The shape of the first modification may be provided not only on the first main surface 1a but also on the second main surface 1b. The angle at which the first recess 4c1 and the second recess 4c2 intersect does not have to be 90°, but may be approximately 90°. Note that the angle θ is not limited to the above value and may be, for example, 0°, 15°, or 30°. In other words, the angle θ may take any value between 0° and 90°.

[0072] The distance between adjacent first recesses 4c1 is, for example, 1 to 10 μm, and the distance between adjacent second recesses 4c2 is, for example, 1 to 10 μm.

[0073] 7B, the shape of the first modified example is formed on the first main surface 1a by embossing an embossing sheet material 5C. The embossing sheet material 5C has a first convex portion 5c1, a second convex portion 5c2, and a concave portion surrounded by the first convex portion 5c1 and the second convex portion 5c2.

[0074] The embossing process may be performed using a sheet material that forms recesses and protrusions on the first main surface 1a of the stretchable substrate 1A. The recesses and protrusions may be arranged in a pattern or randomly. The protrusions may be of different sizes and shapes, and the recesses may be of different sizes and shapes. For example, the embossing sheet material 5 may be a sheet material having diamond-shaped protrusions 4d1 and other partial recesses 4d2 on the first main surface 1a, as shown in FIG. 8A. Alternatively, the embossing sheet material 5 may be a sheet material having wave-shaped protrusions 4e1 and other partial recesses 4e2 on the first main surface 1a, as shown in FIG. 8B. Alternatively, the embossing sheet material 5 may be a sheet material having circular-shaped protrusions 4f1 and other partial recesses 4f2 on the first main surface 1a, as shown in FIG. 8C. Alternatively, the embossing sheet material may be a sheet material having mesh-shaped protrusions 4g1 and other partial recesses 4g2 on the first main surface 1a, as shown in FIG. 8D.

[0075] Third Embodiment The structure of a stretchable device 100B according to a third embodiment will be described with reference to FIG. 9. FIG. 9 is a cross-sectional view of the stretchable device 100B, and corresponds to FIG. 2. The third embodiment differs from the first embodiment in the treatment method performed on the stretchable substrate. This different configuration will be described below. The other configurations are the same as those of the first embodiment, and their description will be omitted. Unless otherwise specified below, the configurations and materials of the stretchable substrate 1B, first main surface 1a, second main surface 1b, and base material 80 can be similar to those of the stretchable substrate 1, first main surface 1a, second main surface 1b, and base material 80 of the first embodiment, respectively.

[0076] As shown in FIG. 9 , the stretchable device 100B has a stretchable substrate 1B having a first main surface 1a and a second main surface 1b facing each other, and wiring 2 provided on the first main surface 1a. In the third embodiment, the first surface 80a of the base material 80 is the same as the first main surface 1a of the stretchable substrate 1B. The surface opposite the second surface 80b of the metal-containing portion 81 is the second main surface 1b of the stretchable substrate 1B. By having the metal-containing portion 81, molecular diffusion that causes autoadhesion in the base material 80 is suppressed, and autoadhesion between stretchable substrates 1B can be suppressed. Here, the metal-containing portion 81 refers to a portion containing a metal-containing compound. Examples of metal-containing compounds include metals and metal oxides.

[0077] The metal-containing portion 81 may contain multiple metal atoms or may contain one type of metal atom. In the third embodiment, the metal-containing portion 81 is located on the second main surface 1b side, but the metal-containing portion 81 may be located on the first main surface 1a side, or the metal-containing portion 81 may be located on both the first main surface 1a side and the second main surface 1b side. The stretchable substrate 1B may have a base material 80 having a metal-containing portion 81, wiring 2 located on the side of the base material 80 opposite the metal-containing portion 81, and another base material 80 located on the wiring 2. The stretchable substrate 1B may also have a metal-containing portion 81 on the surface of the other base material 80 opposite the wiring 2. The base material 80 may consist of only one layer, or multiple layers may be laminated. The stretchable substrate 1B may consist of only one layer, or multiple layers may be laminated.

[0078] Preferably, the metal content of the metal-containing portion 81 on the second main surface 1b measured by X-ray photoelectron spectroscopy is 0.5 atomic % or more. The upper limit of the metal content of the metal-containing portion 81 is not particularly limited, but may be, for example, 3 atomic % or less. The above configuration allows the metal atoms to be uniformly dispersed. This prevents the stretchable substrate 1B from becoming hard. Furthermore, uniform dispersion of the metal atoms allows dispersing coloration resulting from the metal atoms. If the proportion of the metal elements is too high, the safety of the stretchable substrate 1B decreases. If the proportion of the metal elements is too low, molecular diffusion in the base material 80 cannot be suppressed, and, for example, self-adhesion occurs between the stretchable substrates 1B.

[0079] Preferably, the metal-containing portion 81 includes at least one selected from the group consisting of Al, Fe, Ni, Au, Pt, Ag, and Ti. By having the above-mentioned configuration, molecular diffusion that causes self-adhesion in the base material 80 is suppressed, and self-adhesion between the stretchable substrates 1B can be further suppressed.

[0080] Preferably, the metal-containing portion 81 contains Al. The above configuration is preferable from the viewpoint of biocompatibility. In particular, Al is thought to exist in a stabilized form as an oxide, and is preferable from the viewpoint of improving the safety of the stretchable substrate 1B. The above configuration is also preferable from the viewpoint of cost. Note that Al may exist as a metal rather than an oxide.

[0081] Preferably, metal-containing portion 81 contains at least one of a metal and a metal oxide. By having the above-described configuration, metal-containing portion 81 can be stably present on substrate 80. Note that metal-containing portion 81 may contain multiple metal atoms or may contain only a single metal atom.

[0082] Preferably, the stretchable substrate 1B further has a protective layer that protects the wiring 2. The protective layer is provided in the same layer as the wiring 2 or so as to cover the wiring 2. By having the above configuration, the wiring 2 can be protected. The protective layer may be a single layer, or may be a laminate of multiple layers. The protective layer may be a base material 80.

[0083] Preferably, the protective layer covers the wiring 2 and the surface of the protective layer opposite to the wiring 2 has a metal-containing portion 81 .

[0084] (Manufacturing Method) A manufacturing method of the stretchable device 100B will be described with reference to FIGS. 10A, 10B, and 10C.

[0085] First, as shown in FIG. 10A, a substrate 80 is prepared (preparation step). As shown in FIG. 10B, a material for the wiring 2 is formed on the first surface 80a of the substrate 80 (disposition step). As shown in FIG. 10C, a metal-containing portion 81 is formed on the second surface 80b by sputtering (formation step). The sputtering method can be performed using, for example, an ULVAC SV-200. Note that the metal-containing portion 81 may be formed using not only sputtering but also thin-film formation methods such as evaporation and chemical vapor deposition (CVD). This results in the formation of the stretchable device 100B. Alternatively, two substrates 80 may be prepared in the preparation step, and in the disposition step, a material for the wiring 2 may be formed on the first surface 80a of one substrate 80, and the other substrate 80 may be formed on the wiring 2.

[0086] (First Modified Example) As shown in FIG. 11 , in the stretchable device 100C, the base material 80 is formed from a base material 82 and a base material 83. Specifically, the stretchable device 100C has an original stretchable base material 82 so as to cover the metal-containing portion 81, has a base material 83 on the side of the base material 82 opposite the metal-containing portion 81, and has wiring 2 on the side of the base material 83 opposite the base material 82. The surface of the base material 83 on which the wiring 2 is located is the first main surface 1a of the stretchable substrate 1B. Note that the base material 80 may be formed from three or more layers. Note that the reference numerals not specifically described have the same configuration as those in the third embodiment, and the description thereof will be omitted.

[0087] (Second Modification) As shown in FIG. 12 , in a stretchable device 100D, the substrate 80 is formed from a substrate 82 and a substrate 83, and the wiring 2 is sandwiched between the substrate 82 and the substrate 83. Specifically, the stretchable device 100C has a substrate 82, wiring 2 on the substrate 82, and a substrate 83 covering the wiring 2. The surface of the substrate 83 opposite the wiring 2 is the first main surface 1a of the stretchable substrate 1B. A metal-containing portion 81 is provided on the side of the substrate 82 opposite the wiring 2. The substrate 82 may be formed from two or more layers. The substrate 83 may be formed from two or more layers. Furthermore, in the second modification, the metal-containing portion 81 is located on the surface of the substrate 82 opposite the wiring 2, but it may also be located on the surface of the substrate 83 opposite the wiring 2, or on the surface of the substrate 82 opposite the wiring 2 and the surface of the substrate 83 opposite the wiring 2. Note that symbols not specifically described have the same configuration as in the third embodiment, and their description will be omitted.

[0088] <Fourth Embodiment> The configuration of a stretchable device 100E according to the fourth embodiment will be described with reference to FIG. 13. FIG. 13 is a cross-sectional view of the stretchable device 100E, corresponding to FIG. 9. The fourth embodiment does not have the metal-containing portion 81 of the third embodiment, but has a metal-containing region 81d in the substrate 80C. This different configuration will be described below. The other configurations are the same as those of the third embodiment, and their description will be omitted. Unless otherwise specified below, the configurations and materials of the stretchable substrate 1C, first main surface 1a, and second main surface 1b may be similar to those of the stretchable substrate 1, first main surface 1a, and second main surface 1b of the first embodiment. The configuration and materials of the substrate 80C may be similar to those of the substrate 80 of the first embodiment, except for the metal-containing region 81d.

[0089] As shown in FIG. 13 , the stretchable device 100E includes a stretchable substrate 1C having a first main surface 1a and a second main surface 1b facing each other, and wiring 2 provided on the first main surface 1a. In the fourth embodiment, the first surface 80a of the substrate 80C is the same as the first main surface 1a of the stretchable substrate 1C. The second surface 80b of the substrate 80C is the second main surface 1b of the stretchable substrate 1C. On the second surface 80b of the substrate 80C, a metal-containing region 81d is located along the second surface 80b (second main surface 1b). The metal-containing region 81d is present within the stretchable substrate 1C. With this configuration, molecular diffusion that causes autoadhesion in the substrate 80C is suppressed, thereby suppressing autoadhesion of the stretchable substrate 1C. Furthermore, when the stretchable substrate 1C is bonded to a substrate other than the stretchable substrate 1C, the adhesion between the metal-containing region 81d and the other substrate is improved, and the adhesion between the stretchable substrate 1C and the other substrate is also improved. Furthermore, by having the metal-containing region 81d, the stretchable substrate 1C can adhere to other substrates even at low press temperatures. Therefore, for example, adhesion treatment to other substrates is possible even at low temperatures, and the load on the substrate 80C and the wiring 2 due to heat treatment is reduced. The metal-containing region 81d may be located at a position separated from the second main surface 1b of the stretchable substrate 1C.

[0090] Preferably, the ratio of metal atoms contained in the metal-containing region 81d on the second main surface 1b of the stretchable substrate 1C is 0.2 atomic % or more and 2.5 atomic % or less. Here, the ratio on the second main surface 1b refers to the abundance ratio of metal atoms to all atoms on the second main surface 1b. The ratio of metal atoms can be measured using X-ray photoelectron spectroscopy.

[0091] Preferably, the metal-containing regions 81d are scattered on the second surface 80b of the substrate 80C. Specifically, the material constituting the substrate 80C, such as a stretchable resin material, is present between the metal-containing regions 81d. That is, the metal-containing regions 81d do not have a layer shape.

[0092] Preferably, the metal-containing region 81d is a metal or a metal oxide. The above-described configuration allows the metal-containing region 81d to exist safely. The metal-containing region 81d may contain multiple metal atoms or only a single metal atom.

[0093] Preferably, the metal-containing region 81d comprises a metal oxide, more preferably a metal oxide.

[0094] Preferably, the metal-containing region 81d includes at least one selected from the group consisting of Al, Fe, Ni, Au, Pt, Ag, and Ti. By having the above configuration, molecular diffusion that causes self-adhesion in the base material 80C is suppressed, and self-adhesion between the stretchable substrates 1C can be further suppressed.

[0095] Preferably, the metal-containing region 81d contains Al. The above configuration is preferable from the viewpoint of biocompatibility. In particular, Al is thought to exist in a stabilized form as an oxide, and is preferable from the viewpoint of improving the safety of the stretchable substrate 1C. The above configuration is also preferable from the viewpoint of cost. Note that Al may exist as a metal.

[0096] In the fourth embodiment, the metal-containing region 81 d is located on the second main surface 1 b, but the metal-containing region 81 d may be located on the first main surface 1 a, or the metal-containing region 81 d may be located on both the first main surface 1 a and the second main surface 1 b. In this case, the ratio on the first main surface 1 a refers to the abundance ratio, as with the ratio on the second main surface 1 b. The ratio of metal atoms is the ratio to all atoms.

[0097] (Manufacturing Method) A manufacturing method for the stretchable device 100E will be described with reference to FIGS. 14A, 14B, and 14C.

[0098] As shown in Fig. 14A, a substrate 80C having a first main surface 1a and a second main surface 1b facing each other is prepared. As shown in Fig. 14B, wiring 2 is provided on the first main surface 1a of the substrate 80C. As shown in Fig. 14C, a metal-containing region 81d is provided on the substrate 80C. In this way, a stretchable device 100E is formed.

[0099] The present disclosure will be explained in more detail through the following examples, but is not limited to these examples.

[0100] <First Example> (Example 1) Two styrene-based elastomer films were prepared. These styrene-based elastomer films were subjected to ozone treatment by the following method. [Ozone Treatment] The ozone treatment was performed using an SKB2003N manufactured by Sun Energy, which generates ozone using a low-pressure mercury lamp.

[0101] The ratio of oxygen atoms on the surface of the substrate after ozone treatment was measured as follows. [Measurement of ratio of oxygen atoms on the surface of the substrate] The ratio of oxygen atoms on the outermost surface of the substrate was measured using the following device. Device: X-ray photoelectron spectroscopy (XPS, Quantes manufactured by ULVAC-PHI, Inc.) Acceleration voltage: 15 kV Measurement area: 1000 μm × 200 μm

[0102] After the ozone treatment, the ozone-treated surfaces were placed together and the following self-adhesion test was performed. [Self-adhesion test] (1) Measurement at 70°C This was performed based on JIS K 6404-3:1999 (Test method for rubber-coated and plastic-coated fabrics). Specifically, in the blocking test, two glass plates measuring approximately 150 mm in length, 150 mm in width, and 3 mm in thickness were prepared, and the two prepared films were sandwiched between the glass plates in an overlapping state. A weight of 5.0 kg was placed on the glass plates and allowed to stand for 3 hours in an environment at 70°C. Thereafter, it was examined whether the two test pieces peeled off. The test pieces used were films obtained in the examples or comparative examples. ・Adhesion: The test piece could not be peeled off. ・Weak adhesion: The film could be peeled off by applying force. ・Non-adhesion: The film was not adhered. (2) Measurement at room temperature Measurement and evaluation were performed in the same manner as the measurement at 70°C described above, except that the measurement was performed at room temperature.

[0103] (Examples 2 to 6) Two styrene-based elastomer films were prepared in the same manner as in Example 1. These styrene-based elastomer films were subjected to ozone treatment. The ratio of oxygen atoms on the surface of the substrate after the ozone treatment was determined in the same manner as in Example 1. After the ozone treatment, the ozone-treated surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 1.

[0104] Comparative Example 1 Two styrene-based elastomer films were prepared in the same manner as in Example 1. The ratio of oxygen atoms on the surface of the substrate was the same as in Example 1. The two styrene-based elastomer films were stacked together, and a self-adhesion test was performed in the same manner as in Example 1.

[0105] Comparative Example 2 Two styrene-based elastomer films were prepared in the same manner as in Example 1. These styrene-based elastomer films were subjected to ozone treatment. The ratio of oxygen atoms on the surface of the substrate after the ozone treatment was determined in the same manner as in Example 1. After the ozone treatment, the ozone-treated surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 1.

[0106] The results are shown in Table 1.

[0107]

[0108] As shown in Table 1, in Comparative Example 1, no ozone treatment was performed, and the oxygen atom ratio was 1.4 atomic %. That is, before the ozone treatment, the styrene-based elastomer film contained almost no oxygen atoms. In Comparative Example 1, the film was adhesive at room temperature. In Comparative Example 2, the oxygen atom ratio was 2.3 atomic %, but the film was slightly adhesive at room temperature and adhesive under more severe conditions (70°C). In Examples 1 to 6, further oxygen atoms were included, and the film was non-adhesive at room temperature and slightly adhesive even under more severe conditions (70°C). Note that in the above Examples, it was not possible to add oxygen atoms in amounts greater than those listed in Table 1 above.

[0109] <Example 2> (Example 7) Two urethane-based elastomer films were prepared. These styrene-based elastomer films were subjected to ozone treatment using the same method as in Example 1. The ratio of oxygen atoms on the surface of the substrate after the ozone treatment was measured in the same manner as in Example 1. After the ozone treatment, the ozone-treated surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 1.

[0110] (Examples 8 to 12) Two urethane-based elastomer films were prepared in the same manner as in Example 7. These urethane-based elastomer films were subjected to ozone treatment. The ratio of oxygen atoms on the surface of the substrate after the ozone treatment was determined in the same manner as in Example 1. After the ozone treatment, the ozone-treated surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 1.

[0111] Comparative Example 3 Two urethane-based elastomer films were prepared in the same manner as in Example 7. The ratio of oxygen atoms on the surface of the substrate was the same as in Example 1. Two styrene-based elastomer films were stacked together, and a self-adhesion test was performed in the same manner as in Example 1.

[0112] Comparative Example 4 Two urethane-based elastomer films were prepared in the same manner as in Example 7. These urethane-based elastomer films were subjected to ozone treatment. The ratio of oxygen atoms on the surface of the substrate after the ozone treatment was determined in the same manner as in Example 1. After the ozone treatment, the ozone-treated surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 1.

[0113] The results are shown in Table 2.

[0114]

[0115] As shown in Table 2, when the ratio of oxygen atoms was low (Comparative Examples 3 and 4), adhesion occurred at room temperature and 70°C. It was found that by increasing the ratio of oxygen atoms (Examples 7 to 12), a non-adhesive surface could be formed at room temperature and 70°C.

[0116] <Example 3> (Example 13) Two sheets of the same styrene-based elastomer film as in Example 4 were prepared. These styrene-based elastomer films were subjected to ozone treatment. The arithmetic mean surface roughness Ra of the ozone-treated main surface was measured. <Measurement of arithmetic mean surface roughness Ra> Atomic force microscope: atomic force microscope (AFM, manufactured by Bruker) Measurement area: 2 μm × 2 μm Measurement interval: 256 μm × 256 μm

[0117] The ozone-treated surfaces were placed together and heat-treated at 160° C. for 10 minutes.

[0118] (Examples 14 to 17) Two styrene-based elastomer films were prepared in the same manner as in Example 4. These styrene-based elastomer films were subjected to ozone treatment. The arithmetic mean surface roughness Ra of the ozone-treated main surfaces was measured in the same manner as in Example 13. The ozone-treated surfaces were placed together, and heat treatment was performed as shown in Table 3.

[0119] The results are shown in Table 3. For comparison, Table 3 also shows Example 4, which was not subjected to heat treatment.

[0120]

[0121] As shown in Table 3, Example 4 (without heat treatment) was non-adhesive at room temperature, but was slightly tacky under more severe conditions (70°C). Examples 14 to 17 were non-adhesive not only at room temperature but also at 70°C. Examples 14 to 17 had a large arithmetic mean surface roughness Ra, and it is believed that having such a surface allows the formation of a non-adhesive surface at room temperature and 70°C.

[0122] A specific explanation will be given based on FIG. 15. FIG. 15 is an explanatory diagram illustrating the surface roughness of the stretchable substrate. FIG. 15 is based on a photograph obtained by measuring the surface roughness of the substrate of Example 15 using an atomic force microscope. In FIG. 15, the surface hardness increases in the order of white portion 61, coarse dot portion 62, and fine dot portion 63. It was found that by performing heat treatment at 160°C, the dot portion 62 and dot portion 63 increase, and the surface of the substrate can be roughened. Note that in the above Examples 13 to 17, the ratio of oxygen atoms is considered to be 5 atomic % or more.

[0123] <Example 4> (Example 18) As in Example 4, two styrene-based elastomer films were prepared. These styrene-based elastomer films were subjected to ozone treatment. The film after the ozone treatment was divided into a first portion and a second portion, which have different phases measured by an electron force microscope, and the surface coverage of the first portion, which is a hard portion with no phase delay, was measured. <Measurement of Surface Coverage> Apparatus: Atomic Force Microscope (AFM, manufactured by Bruker) Measurement Area: 2,000 μm × 2,000 μm

[0124] Thereafter, the ozone-treated surfaces were placed together and subjected to a heat treatment. After the heat treatment, a self-adhesion test was carried out in the same manner as in Example 1.

[0125] (Examples 19 to 22) Two styrene-based elastomer films were prepared in the same manner as in Example 18. These styrene-based elastomer films were subjected to ozone treatment. The film after the ozone treatment was divided into a first portion and a second portion, which had different phases as measured by an electron force microscope, and the surface occupancy of the first portion, which was a hard portion with no phase delay, was measured in the same manner as in Example 18.

[0126] The results are shown in Table 4. For comparison, Table 4 also shows Example 4, which was not subjected to heat treatment.

[0127]

[0128] As shown in Table 4, Example 4, which was subjected to ozone treatment only, was non-adhesive at room temperature, but became slightly adhesive at 70°C. In contrast, Examples 18 to 22, which were subjected to heat treatment after ozone treatment, were non-adhesive at room temperature and 70°C. It is believed that in Examples 18 to 22, the surface occupancy rate increased due to the heat treatment, resulting in non-adhesiveness not only at room temperature but also at 70°C. A specific explanation will be given based on Figure 16. In Figure 16, there are a first portion 71 and a second portion 72 shown in particulate form. As shown in Figure 16, it was found that the proportion of the first portion 71 increased due to the heat treatment.

[0129] <Fifth Example> (Reference Example 23) As in Comparative Example 3, two urethane-based elastomer films were prepared. These urethane-based elastomer films were stacked, and an embossing film was pressed against them to perform embossing. <Embossing Film> The embossing film had a lattice shape, with a rectangular first shape 4A having vertical grooves and a rectangular second shape 4B having horizontal grooves. The rectangles were 25 μm square. The first shape 5A and second shape 4B each had 3 to 10 grooves.

[0130] After embossing, the arithmetic mean surface roughness Ra' of the surface was measured using a laser microscope. <Measurement of arithmetic mean surface roughness Ra'> Laser microscope: VK-9500 (manufactured by Keyence Corporation) Measurement method: laser non-contact Measurement area: 1,012 μm×1,350 μm

[0131] (Examples 24 and 25) Two urethane-based elastomer films were prepared in the same manner as in Reference Example 23. These urethane-based elastomer films were stacked and pressed under pressure using the same embossing film as in Reference Example 23 under the following conditions. However, the depth of the pressure press was greater than in Reference Example 23. <Press Press> The film was heated to 70°C and hot pressed for 1 minute. The arithmetic mean surface roughness Ra' of the surface after embossing was measured in the same manner as in Reference Example 23.

[0132] The results are shown in Table 5.

[0133]

[0134] As shown in Table 5, Comparative Example 3 was not embossed and was adhesive at room temperature. Reference Example 23 was non-adhesive at room temperature. Examples 24 and 25 were non-adhesive at room temperature and 70°C. This is thought to be because the arithmetic mean surface roughness Ra' was larger after embossing (Reference Example 23, Examples 24 and 25) than before embossing (Comparative Example 3), the area of ​​the tops of the convex portions was smaller, and the contact area was reduced.

[0135] Sixth Example (Examples 26 to 29) Two styrene-based elastomer films were prepared. These styrene-based elastomer films were subjected to a sputtering treatment using Al metal using an SV-200 sputtering machine manufactured by ULVAC. X-ray photoelectron spectroscopy (XPS) revealed that aluminum oxide was formed.

[0136] The measurement of the composition ratio of the Al element in the substrate after the sputtering treatment and the measurement of the self-adhesion test were carried out in the same manner as in Example 1.

[0137] The results are shown in Table 6. For comparison, Table 6 also shows Comparative Example 1, in which no sputtering treatment was performed.

[0138]

[0139] As shown in Table 6, in Comparative Example 1, no sputtering treatment was performed and self-adhesion occurred at both room temperature and 70°C. In Examples 26 to 29, non-adhesiveness was achieved by performing sputtering treatment. In particular, in Examples 28 and 29, in which the Al ratio was 0.5 atomic % or more, non-adhesiveness was achieved even under more severe conditions (70°C).

[0140] Furthermore, the stretchable substrate containing Al obtained in Example 26 was subjected to a cytotoxicity test specified in ISO 10993-5, but no toxicity was observed. The reason for this is thought to be that the amount of Al formed on the surface using this method is extremely small, and because there is only a small amount, it is stabilized as an oxide. We believe that this result demonstrates the safety of the stretchable substrate obtained using this method.

[0141] Seventh Example (Examples 30 to 33) Two urethane-based elastomer films were prepared. These urethane-based elastomer films were subjected to a sputtering treatment using Al metal using the same method as in Example 26. After the sputtering treatment, the sputtered surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 26.

[0142] The results are shown in Table 7. For comparison, Table 6 also shows Comparative Example 3, in which no sputtering treatment was performed.

[0143]

[0144] As shown in Table 7, in Comparative Example 3, no sputtering treatment was performed and self-adhesion occurred at both room temperature and 70°C. In Examples 30 to 33, non-adhesiveness was achieved by performing sputtering treatment. In particular, in Examples 32 and 33, in which the Al ratio was 0.5 atomic % or more, non-adhesiveness was achieved even under more severe conditions (70°C).

[0145] Eighth Example (Examples 34 to 39) Two urethane-based elastomer films were prepared. These urethane-based elastomer films were subjected to a sputtering treatment using the metals shown in Table 8, using the same method as in Example 26. After the sputtering treatment, the sputtered surfaces were placed together, and a self-adhesion test was performed in the same manner as in Example 26.

[0146] The results are shown in Table 8.

[0147]

[0148] As shown in Table 8, it was found that the use of Fe, Ni, Au, Pt, Ag, and Ti resulted in the suppression of self-adhesion between stretchable substrates. It was confirmed that forming a metal or metal oxide film on the substrate can suppress self-adhesion. It is believed that the presence of a small amount of metal on the substrate, not just Al and the metals shown in Table 8, can also produce a film that can suppress molecular diffusion, resulting in a similar effect.

[0149] <Example 9> (Example 40) Two styrene-based elastomer films were prepared. These styrene-based elastomer films were subjected to plasma treatment. [Plasma Treatment] The plasma treatment was performed using PC-1000 (Samco Corporation).

[0150] X-ray photoelectron spectroscopy (XPS) showed that aluminum oxide was formed on the plasma-treated film, with the proportion of aluminum atoms on the plasma-treated surface being 0.8 atomic % of the total elements.

[0151] After the plasma treatment, the plasma-treated surfaces were placed together and a self-adhesion test was conducted, which confirmed that there was no adhesion between the elastomers.

[0152] After the plasma treatment, the substrate was press-bonded to a nylon substrate for 1 minute at 100-120°C using a polyester urethane adhesive. The pressure was set at 0.6 MPa. Then, a 180° peel test was performed as shown in Figure 17. The results are shown in Figures 18 and 19. Figure 18 shows the peel force of the substrate of Example 40 at 2.19 N / 10 mm. －１ The results were compared with those of Comparative Example 5, where the peel force was 0.28 N / 10 mm. －１ The results are shown below. [180° Peel Test (Peel Strength)] A 180° peel test was performed with reference to JIS Z 0237 180° Peel Test for Pressure-Sensitive Adhesive Tape and JIS Z 0238 Test Method for Heat-Sealed Flexible Packaging Bags and Semi-Rigid Containers. Specifically, the plasma-treated substrate 80C and the nylon-based substrate 92 were bonded via an adhesive layer 91 made of an adhesive, and a tensile force F was applied to the substrate 80C and the nylon-based substrate 92 in directions away from each other, i.e., directions 180° apart, to peel them off. A force gauge was used to measure the peel strength. Note that aluminum oxide, which is the metal-containing region 81d, was present on the surface of the substrate 80C facing the adhesive layer 91.

[0153] (Examples 41 and 42) After the plasma treatment, the same treatment as in Example 40 was carried out except that the pressing temperature was changed, and a peel test was carried out.

[0154] Comparative Example 5 Two styrene elastomer films were prepared in the same manner as in Example 40. The styrene elastomer films were stacked and a self-adhesion test was performed. A 180° peel test was also performed as shown in Figure 17. Note that in this Comparative Example 5, unlike Figure 17, no plasma treatment was performed and no aluminum oxide was formed. Of the two peel force measurement results shown in Figure 18, in Comparative Example 5, the peel force was the lowest value of 0.28 N·10 mm －１ It was.

[0155] Comparative Examples 6 and 7 After the plasma treatment, the same treatment as in Comparative Example 5 was carried out except that the pressing temperature was changed, and a peel test was carried out.

[0156] The results are shown in Table 9.

[0157]

[0158] 18, Example 40, which was subjected to plasma treatment, had a greater peel force in the 180° peel test than Comparative Example 5, which was not subjected to plasma treatment. In other words, plasma treatment increased the adhesion strength.

[0159] In Figure 19, the results of Examples 40-42 are represented by black squares, and the results of Comparative Examples 5-7 are represented by black circles. As shown in Table 9 and Figure 19, in Examples 40-42, there was little variation in peel strength even when the press temperature fluctuated, and good peel strength was maintained regardless of the difference in press temperature. In contrast, in Comparative Examples 5-7, the peel force was smaller than in Examples 40-42, and further, fluctuations in press temperature affected the peel strength. Specifically, in Comparative Examples 5-7, peeling became easier as the press temperature decreased. As described above, it was found that in Examples 40-41, high peel strength could be obtained even at low press temperatures. By being able to adhere at low temperatures, the load caused by heat treatment on the stretchable substrate and wiring is reduced.

[0160] In the above Examples 1 to 22, 24 to 42 and Reference Example 23, the physical properties were measured using only the substrate, but the same measurement can be carried out when wiring is attached.

[0161] The present disclosure is not limited to the above-described embodiments, and design modifications are possible within the scope of the present disclosure. For example, the respective features of the first to fourth embodiments may be combined in various ways.

[0162] This application claims priority based on Japanese Patent Application No. 2023-116845, filed on July 18, 2023, the entire contents of which are incorporated herein by reference.

[0163] The present disclosure includes the following aspects. <1> A stretchable substrate having a first main surface and a second main surface opposing each other, wherein the stretchable substrate has any one of the following: (1) an oxygen atomic ratio of at least one of the first main surface and the second main surface measured by X-ray photoelectron spectroscopy is 5 atomic % or more relative to all atoms, (2) an arithmetic mean surface roughness of the first main surface or the second main surface measured by a laser microscope is 6 μm or more, (3) at least one of the first main surface and the second main surface has a metal-containing portion containing metal atoms, and (4) a metal-containing region containing metal atoms is located along at least one of the first main surface and the second main surface. <2> The stretchable substrate according to <1>, wherein the oxygen atomic ratio of at least one of the first main surface and the second main surface measured by X-ray photoelectron spectroscopy is 5 atomic % or more relative to all atoms. <3> The stretchable substrate according to <2>, wherein the oxygen atomic ratio in central portions of the first main surface and the second main surface in a direction perpendicular to the first main surface and the second main surface is 5 atomic % or less. <4> The stretchable substrate according to <2> or <3>, wherein the arithmetic mean surface roughness of the first main surface or the second main surface measured with the atomic force microscope is 10 nm or more. <5> The stretchable substrate according to any one of <2> to <4>, wherein the first main surface or the second main surface has a first portion and a second portion having different phases measured with the atomic force microscope, the phase of the first portion leads the phase of the second portion by 10° or more, and the surface occupancy rate of the first portion is 80% or more. <6> The stretchable substrate according to <1>, wherein the arithmetic mean surface roughness of the surface of the first main surface or the second main surface measured with the laser microscope is 6 μm or more. <7> The stretchable substrate according to <1>, wherein at least one of the first main surface and the second main surface has the metal-containing portion containing the metal atom. <8> The stretchable substrate according to <7>, wherein in the first main surface or the second main surface, a composition ratio of the metal in the metal-containing portion to all elements measured by X-ray photoelectron spectroscopy is 0.5 atomic % or more.<9> The stretchable substrate according to <7> or <8>, wherein the oxygen atomic ratio in central portions of the first main surface and the second main surface in a direction perpendicular to the first main surface and the second main surface is 5 atomic % or less. <10> The stretchable substrate according to <1>, wherein the metal-containing region containing the metal atoms is located along at least one of the first main surface and the second main surface. <11> The stretchable substrate according to <10>, wherein the ratio of the metal atoms in the first main surface or the second main surface is 0.2 atomic % or more and 2.5 atomic % or less. <12> The stretchable substrate according to any one of <7> to <11>, wherein the metal atoms include at least one selected from the group consisting of Al, Fe, Ni, Au, Pt, Ag, and Ti. <13> The stretchable substrate according to any one of <7> to <9> or <12>, wherein the metal-containing portion includes at least one of a metal and a metal oxide. <14> The stretchable substrate according to any one of <10> to <12>, wherein the metal-containing region contains at least one of a metal and a metal oxide. <15> The stretchable substrate according to any one of <1> to <14>, wherein the stretchable substrate is rubber or an elastomer. <16> A stretchable device comprising the stretchable substrate according to any one of <1> to <15> and wiring arranged on the first main surface of the stretchable substrate. <17> A stretchable device comprising the stretchable substrate according to any one of <2> to <5>, <10> to <12>, <14> or <15> and wiring arranged on the first main surface of the stretchable substrate. <18> A stretchable device comprising the stretchable substrate according to any one of <6> to <9>, <12>, <13> or <15> and wiring arranged on the first main surface of the stretchable substrate. <19> The stretchable device according to <18>, further comprising a protective layer. <20> The stretchable device according to <19>, wherein the protective layer covers the wiring, and a surface located opposite to the wiring has the metal-containing portion. <21> A method for manufacturing a stretchable substrate, comprising: a preparation step of preparing a base material; and an ozone treatment step of performing ozone treatment on at least one of a first main surface of the base material and a second main surface located opposite to the first main surface.<22> The method for producing a stretchable substrate according to <21>, wherein the stretchable substrate contains 5 atomic % or more of oxygen atoms in at least one of the first main surface and the second main surface. <23> The method for producing a stretchable substrate according to <21> or <22>, wherein the ratio of oxygen atoms in at least one of the first main surface and the second main surface of the stretchable substrate is increased by 5 atomic % or more relative to the base material. <24> The method for producing a stretchable substrate according to any one of <21> to <23>, further comprising, after the ozone treatment step, an embossing step of embossing at least one of the first main surface and the second main surface. <25> A method for producing a stretchable device, comprising: a step of preparing a base material having a first main surface and a second main surface facing each other; an arrangement step of arranging wiring on the first main surface of the base material; and an ozone treatment step of performing ozone treatment on at least one of the first main surface and the second main surface after the arrangement step. <26> A method for manufacturing a stretchable device, comprising: a step of preparing a substrate having a first main surface and a second main surface opposing each other; an arrangement step of arranging wiring on the first main surface of the substrate; and an embossing step of embossing at least one of the first main surface and the second main surface after the arrangement step. <27> A method for manufacturing a stretchable device, comprising: a preparation step of preparing a substrate; and a formation step of forming a metal-containing portion on at least one of the first main surface and a second main surface opposite the first main surface of the substrate. <28> A method for manufacturing a stretchable device, comprising: a preparation step of preparing a first substrate having a first main surface and a second main surface opposing each other; and a formation step of forming a metal-containing portion on at least the second main surface of the first substrate. <29> The method for manufacturing a stretchable device according to <28>, comprising: an arrangement step of arranging wiring on the first main surface of the substrate after the preparation step and before the formation step. <30> The method for manufacturing a stretchable device according to <29>, further comprising: preparing a second base material having a first main surface and a second main surface facing each other; and arranging the first main surface of the second base material on the wiring in the arranging step.

[0164] 100, 100A, 100B, 100C, 100D, 100E Stretchable device 1, 1A, 1B, 1C Stretchable substrate 2 Wiring 3 Sheet material 4A First shape 4B Second shape 4a1, 4b1 Convex portion 4a2, 4b2 Concave groove portion 5, 5C Sheet material for embossing 5a1 Warp portion 5b1 Weft portion 61 White portion 62 Coarse dot portion 63 Fine dot portion 71 First portion 72 Second portion 80, 82, 83 Base material 81 Metal-containing portion

Claims

1. A stretchable substrate having a first main surface and a second main surface facing each other, The aforementioned stretchable substrate is The oxygen atom ratio of at least one of the first principal surface and the second principal surface, as measured by X-ray photoelectron spectroscopy, is 5 atomic percent or more relative to the total atoms. The oxygen atom ratio in the central portion of the first and second principal surfaces in directions perpendicular to the first and second principal surfaces is 5 atomic percent or less. Stretchable substrate.

2. In the first main surface or the second main surface, the arithmetic mean surface roughness of the surface measured by the laser microscope is 6 μm or more. The stretchable substrate according to claim 1.

3. At least one of the first main surface and the second main surface has a metal-containing portion containing metal atoms. The stretchable substrate according to claim 1.

4. The stretchable substrate according to claim 3, wherein, in the first main surface or the second main surface, the composition ratio of the metal in the metal-containing portion to the total elements, as measured by X-ray photoelectron spectroscopy, is 0.5 atomic percent or more.

5. A metal-containing region containing metal atoms is located along at least one of the first main surface and the second main surface. The stretchable substrate according to claim 1.

6. The stretchable substrate according to claim 5, wherein the ratio of the metal atoms in the first main surface or the second main surface is 0.2 atomic% or more and 2.5 atomic% or less.

7. The stretchable substrate according to claim 3, wherein the metal atom comprises at least one selected from the group consisting of Al, Fe, Ni, Au, Pt, Ag, and Ti.

8. The stretchable substrate according to claim 1, wherein the substrate is made of rubber or elastomer.

9. A stretchable device comprising a stretchable substrate according to any one of claims 1 to 8, and wiring arranged on the first main surface of the stretchable substrate.

10. The invention comprises a stretchable substrate according to claim 2 or 3, wiring arranged on the first main surface of the stretchable substrate, and a protective layer. The protective layer covers the wiring, The expandable device according to claim 9, wherein the surface located opposite to the wiring has the metal-containing portion.