Heating element and drive unit

Abstract

To provide a heating element in which a wiring pattern of electrodes is formed in a space-saving manner, capable of rapidly heating a localized area with a small amount of power and to provide a drive device using the same.SOLUTION: The heating element includes a substrate, a wiring electrode of a positive electrode and a wiring electrode of a negative electrode, formed on the substrate and oppose each other and a resistive element formed between the wiring electrodes of the positive electrode and the negative electrode opposing each other. The wiring electrodes of the positive electrode and negative electrode have a configuration in which the normal angle of the facing surface is 70 degrees or more and the top surface has a recess. The drive device has a flexible sheet (stretchable sheet) consisting of two or more layers of sheets with different coefficients of linear expansion pasted together as a substrate and has incisions inserted on the periphery of the heating element.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to a heating element and a driving device that utilizes the heating element. [Background technology]

[0002] Known examples of heating elements include planar heating sheets formed by inserting or applying a resistor with high volume resistivity, such as a carbon-based resistor, between the positive and negative electrodes of a wiring electrode pattern printed on a sheet.

[0003] Patent Document 1 discloses a planar heating element in which a resistor is formed by printing and drying on a comb-tooth shaped wiring electrode pattern formed by printing and drying, and which has multiple heating parts with different pitches between the positive and negative comb-tooth electrodes, allowing temperature adjustment according to the user's preference. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 4449804 Summary of the Invention [Problem to be solved by the invention]

[0005] However, Patent Document 1 does not disclose any awareness of the problem of forming an electrode wiring pattern in a space-saving manner and instantaneously generating heat in a localized, pinpoint area of ​​a few square millimeters.

[0006] Therefore, the present invention aims to provide a heating element that can rapidly generate heat in a localized area with a small amount of power, with an electrode wiring pattern formed in a space-saving manner, and to provide a driving device that uses the heating element. [Means for solving the problem]

[0007] In order to solve the above-mentioned problems, one representative heating element of the present invention is a heating element comprising a substrate, a positive wiring electrode and a negative wiring electrode formed on the substrate and facing each other, and a resistor formed between the facing positive and negative wiring electrodes, wherein the positive and negative wiring electrodes have a slope angle of 70 degrees or more on their opposing side surfaces and have a recess on their upper surfaces. [Effects of the Invention]

[0008] According to the present invention, the wiring pattern of the electrodes of the heating element can be formed in a space-saving manner, and it is possible to rapidly generate heat in a localized area with a small amount of power. Problems, configurations, and effects other than those described above will become apparent from the following description of the preferred embodiments. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a diagram showing a conventional heating element 200 using wiring electrodes. [Figure 2] FIG. 2 is a cross-sectional view of the heating element 200 cut along the XZ plane including the XX' axis. [Figure 3] Figure 3 is a micrograph of the cross-section of wiring printed using a conventional method. [Figure 4] FIG. 4 is a diagram showing a schematic diagram of a heating element 500 using wiring electrodes according to the present invention. [Figure 5] FIG. 5 is a cross-sectional view of the heating element 500 cut along the XZ plane including the XX' axis. [Figure 6] FIG. 6 shows the cross-sectional shape of the wiring electrode formed by the screen printing method of the present invention. [Figure 7] FIG. 7 is a plan view of a photograph taken by a laser microscope of the wiring electrodes formed by the screen printing method of the present invention. [Figure 8] FIG. 8 is a perspective view of a photograph taken by a laser microscope of a wiring electrode formed by the present screen printing method. [Figure 9] FIG. 9 is a cross-sectional view of a photograph taken by a laser microscope of a wiring electrode formed by the present screen printing method. [Figure 10] FIG. 10 is a schematic diagram showing the Joule heat formula. [Figure 11] FIG. 11 is a diagram showing the injection step in the screen printing method of the present invention. [Figure 12] FIG. 12 is a diagram showing the sweeping step using a squeegee in the screen printing method of the present invention. [Figure 13] FIG. 13 is a diagram showing recesses formed in the screen mesh marks when the coating agent and printing method according to this embodiment are used. [Figure 14] FIG. 14 is a diagram showing recesses formed in the screen mesh marks when the coating agent and printing method according to this embodiment are used. [Figure 15] FIG. 15 is a diagram showing a heating element and a driving device according to the first embodiment. [Figure 16] FIG. 16 is a plan view showing a heating element and a driving device according to the second embodiment. [Figure 17] FIG. 17 is a comparison graph of the temperature rise of a heating element using the wiring electrode pattern according to the present invention and a heating element using conventional wiring electrodes. [Figure 18] FIG. 18 is a plan view of an LED flicker 806 to which the second embodiment is applied. [Figure 19] FIG. 19 is a plan view of a butterfly device 808 to which the second embodiment is applied. [Figure 20] FIG. 20 is a plan view showing a heating element and a driving device according to the third embodiment. [Figure 21] FIG. 21 is a plan view showing a heating element and a driving device according to the fourth embodiment. [Figure 22] FIG. 22 is a longitudinal cross-sectional view of a balloon capillary 1200 according to the fifth embodiment. [Figure 23] FIG. 23 is a schematic diagram of an example of the balloon driving unit 1203. As shown in FIG. [Figure 24] FIG. 24 is a schematic diagram showing how the balloon driving unit 1203 is driven. [Figure 25]FIG. 25 is a longitudinal cross-sectional view of a modified example of the balloon capillary 1200 according to the fifth embodiment. [Figure 26] FIG. 26 is a schematic diagram of a Braille display device 1300 to which the fifth embodiment is applied. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, an embodiment of the present invention will be described with reference to the drawings, but the present invention is not limited to this embodiment. In addition, in the drawings, the same parts are denoted by the same reference numerals.

[0011] In this disclosure, directions indicated by the X-axis, Y-axis, and Z-axis indicated on the drawings may be used to indicate directions.

[0012] In this disclosure, unless otherwise specified, "up" refers to the positive direction of the Z axis, "down" refers to the negative direction, and "height" refers to the length on the Z axis.

[0013] In this disclosure, unless otherwise specified, the surface of the substrate that is in contact with the wiring electrode is parallel to the XY plane. The "bottom surface" refers to the surface of the wiring electrode that is in contact with the substrate (XY plane).

[0014] In this disclosure, unless otherwise specified, a view viewed from above on the XY plane is referred to as a plan view, and a view viewed on the XZ plane is referred to as a cross-sectional view.

[0015] First, a conventional example will be described with reference to FIGS. Fig. 1 is a diagram showing a heating element 200 using conventional wiring electrodes. In Fig. 1, the comb-shaped electrode portions of a positive wiring electrode 202 and a negative wiring electrode 203 are combined and arranged on a substrate 301 so that they are mutually adjacent in the X-axis direction. The heating element is formed by filling the gaps between these comb-shaped electrodes with resistors 204 (not shown).

[0016] The bottom surfaces of the positive wiring electrode 202 and the negative wiring electrode 203, where they are in contact with the substrate 301, have parallel sides (hereinafter referred to as "opposing parallel sides") that face each other across the resistor 204. In FIG. 1, the opposing parallel sides are parallel to the Y axis. In addition, the surfaces of the positive wiring electrode 202 or the negative wiring electrode 203 that include the opposing parallel sides and face each other across the resistor 204 are referred to as "opposing side surfaces."

[0017] 2 is a cross-sectional view of the heating element 200 in FIG. 1 taken along the XZ plane including the X-X' axis. The X-X' axis is a straight line perpendicularly intersecting the opposing parallel sides at any position. The cross sections of the positive wiring electrode 202 and the negative wiring electrode 203 are semi-cylindrical, diverging from top to bottom. Distance 302 represents the minimum distance in the X direction between the opposing side surface 206 on the positive wiring electrode 202 side and the opposing side surface 207 on the negative wiring electrode 203 side, and distance 303 represents the maximum distance.

[0018] Figure 3 is a micrograph of the cross-section of wiring printed using a conventional method. As mentioned above, it can be seen that the cross-section has a semi-cylindrical shape.

[0019] Fig. 4 is a schematic diagram showing a heating element 500 using wiring electrodes according to an embodiment of the present invention. Fig. 5 is a cross-sectional view of heating element 500 in Fig. 4 taken along the XZ plane including the X-X' axis. In the following description, components that are the same as or equivalent to those in the above-described conventional example are given the same reference numerals, and their description will be simplified or omitted.

[0020] In this embodiment, the cross sections of the positive wiring electrode 502 and the negative wiring electrode 503 are substantially rectangular and are formed to stand substantially perpendicular to the substrate. An opposing side surface 506 on the positive wiring electrode 502 side and an opposing side surface 507 on the negative wiring electrode 503 side face each other substantially parallel to each other. Therefore, the distance between the opposing side surfaces 506 and 507 is substantially the same in the Z direction.

[0021] The structure of the wiring electrodes of the heating element of this embodiment will be described in detail below. The wiring electrodes in this embodiment are formed using a screen printing method (hereinafter referred to as the "screen printing method") described below. The screen printing method is described in detail in the specification and drawings of Japanese Patent Application No. 2021-105169 (hereinafter referred to as the "prior application"), which is a prior application filed by the applicant.

[0022] Figure 6 shows the cross-sectional shape of a wiring electrode formed by the present screen printing method. This corresponds to the cross-sectional shape of the positive wiring electrode 502 or the negative wiring electrode 503 shown in Figure 5. The line segment connecting the X-direction ends X1 and X2 of the bottom surface of the wiring electrode is called the "bottom base," and its length is L1. Hereinafter, L1 is also referred to as the "electrode width."

[0023] The inflection point (the point where the slope changes from increasing to decreasing) when tracing from X1 along the opposing side surface in the positive direction of the Z axis is designated X3. The inflection point obtained in a similar manner from X2 on the other opposing side surface of the wiring electrode is designated X4. The line segment connecting X3 and X4 is called the "upper base," and its length is designated L2. The angle between the line segment connecting inflection points X3 and X1 and the lower base is called the "slope angle," and is designated θ1. Although not shown in the figure, the slope angle between the line segment connecting X2 and X4 and the lower base is similarly designated θ2. In the following description, the surface of the wiring electrode above the upper base will be referred to as the upper surface.

[0024] Next, the cross-sectional shape of the wiring electrodes formed by the present screen printing method will be described in detail with reference to FIGS. 7 to 9 are photographs taken with a Keyence laser microscope of wiring electrodes formed by the screen printing method of this invention with a screen printing plate having a groove width of 200 μm, a groove depth of 200 μm, and a groove pitch of 200 μm.

[0025] Fig. 7 is a plan view of a wiring electrode formed by the present screen printing method, taken by a laser microscope. Fig. 8 is a perspective view of a wiring electrode formed by the present screen printing method, taken by a laser microscope. Fig. 9 is a cross-sectional view of a wiring electrode formed by the present screen printing method, taken by a laser microscope.

[0026] Table 1 shows the measurement results of the upper base (L2) and lower base (L1). From the value of the lower base, it can be seen that the electrode width (L1) is almost the same as the length of the stencil groove width. [Table 1]

[0027] Table 2 shows the results of measuring the slope angle for several combinations of groove width and groove depth. In Table 2, "left" refers to θ1, and "right" refers to θ2. The slope angle can be measured from the profile shape of the wiring electrode in the cross-sectional view of Figure 9. [Table 2] As is clear from Table 2, the angle of the slope of the wiring electrodes formed using the screen printing method of the present invention is 70 degrees or more within the aspect ratio range of 0.5 to 4, and is therefore approximately vertical.

[0028] Another characteristic of the cross-sectional shape of the wiring electrode formed using the present screen printing method is the presence of recesses in the cross-sectional shape of the upper surface, as can be seen in Figure 6 or Figures 7 to 9. This is due to the unique phenomenon that recesses are formed at the intersections of the screen mesh when using the present screen printing method. As will be described later, this is due to the fact that during printing, a lubricant that prevents cohesive failure of the electrode seeps out of the coating material at the areas where the intersections of the screen mesh on the upper surface of the wiring electrode come into contact. In the cross-sectional shape of Figure 6, the width l3 of the recesses, which is the distance between the vertices, is 10 to 40 μm.

[0029] In contrast to the conventional screen printing method in which the wiring electrodes are semi-cylindrical and have convex portions on the upper surface as explained in Figures 1 to 3, this can be said to be a structural feature of the wiring electrodes formed by the screen printing method of the present invention.

[0030] <Wire electrode line width, pitch, and aspect ratio> The heating element and driving device in this embodiment are intended to generate heat and drive using space-saving wiring at a low voltage of approximately 5 V. For the wiring electrodes to achieve this, it is desirable that the electrode width (corresponding to L1 in FIG. 6) be 100 to 200 μm, the spacing (pitch) between electrodes be approximately the same as or twice the electrode width, and the aspect ratio (ratio of height to electrode width) be 0.5 to 4. Conventionally, when forming electrodes with a width of 200 μm in parallel, a pitch width of 500 to 1,000 μm is required, but by using the wiring electrodes of this embodiment, space can be saved.

[0031] <Actions and Effects> Next, the effects of this embodiment Figure 10 is a schematic diagram for explaining the formula for Joule heat. Joule heat is expressed by the following formula.

number

[0032] In the case of wiring electrodes made by a conventional printing method, the cross section of the electrode is semi-cylindrical as shown in Figures 1 to 3, so most of the current flowing from the positive wiring electrode 202 to the negative wiring electrode 203 flows near the gap 302 where the resistance length is short, and the heat generation efficiency is poor even in terms of Joule's formula.

[0033] Furthermore, with an electrode having a semi-cylindrical cross section, it is not possible to ensure a sufficient film thickness in the height direction, and it is not possible to obtain a cross-sectional area of ​​the printed wiring or electrode that is sufficient to generate the desired amount of heat. Therefore, conventionally, a resistor is formed by printing a comb-shaped electrode with a wide line width of about 10 microns, which is the limit of film thickness for screen printing, and with low aspect ratio electrodes, with positive and negative electrodes arranged alternately. With this type of specification, it is possible to ensure a certain amount of heat generation if a large area is used, but it is not possible to obtain a large amount of heat generation over an area of ​​several millimeters. To increase the rate of temperature rise over an area of ​​several millimeters, a high voltage of several tens of volts is required, and a voltage of around 5V will result in almost no temperature rise.

[0034] In contrast, the positive wiring electrode 502 and the negative wiring electrode 503 of the present invention have opposing side surfaces 506 and 507 that face each other in a generally parallel manner, so that current flows relatively uniformly throughout the entire resistor, resulting in good heat generation efficiency. Furthermore, because current flows widely throughout the entire cross-sectional area A [m2], Joule heat Q [W] can be increased.

[0035] The electrode width, pitch, aspect ratio, and drive voltage are all related to one another, so that even if the pitch is increased, the same amount of heat can be generated at the same voltage if the aspect ratio is increased. Therefore, by using the wiring electrode structure of this embodiment, it is possible to increase the degree of freedom in designing the heating element. Furthermore, the electrode width, pitch, and aspect ratio are largely determined by the specifications of the screen printing plate actually used in production, and if a screen printing plate of the desired dimensions is available, it is possible to manufacture one with a pitch shorter than the electrode width (for example, a pitch 0.5 times larger), or an aspect ratio of 4 times or more.

[0036] The screen printing method used to form the wiring electrodes in this embodiment will be described below.

[0037] <Printing ink> The positive electrode and negative electrode that can be used in this embodiment are electrodes printed with a coating agent containing an incompatible additive as a printing ink in a mixture (main agent) of a filler and a binder and a main solvent that is a solvent for the binder.

[0038] In this embodiment, inorganic and organic fillers can be used as fillers for electrodes. Inorganic fillers are classified into metals and non-metals. Organic fillers are mainly polymer compositions. Metals include noble metals and base metals. For example, noble metals include gold, silver, platinum, and palladium, while base metals include iron, copper, nickel, aluminum, lead, zinc, tin, tungsten, molybdenum, tantalum, magnesium, cobalt, bismuth, cadmium, titanium, zirconium, antimony, manganese, beryllium, chromium, germanium, vanadium, gallium, hafnium, indium, niobium, rhenium, and thallium. Gold, silver, and copper are particularly useful in this embodiment. Non-metals are elements other than the metals mentioned above. For example, when classified by reactivity, reactive non-metals include hydrogen, carbon, nitrogen, oxygen, fluorine, phosphorus, sulfur, chlorine, bromine, selenium, iodine, and astatine; noble gases include helium, neon, argon, krypton, xenon, and radon; and semi-metals that have chemical properties similar to non-metals include boron, silicon, germanium, arsenic, antimony, and tellurium. However, inorganic fillers also include substances in which multiple elements are chemically bonded, such as calcium carbonate, silica, carbon black, graphite, carbon nanotubes, alumina, aluminum nitride, boron nitride, beryllium, barium titanate, lead zirconate titanate, ferrite, CMC, titanium oxide, glass beads, magnesium oxide, hydrotalcite, MOS, barium sulfate, titanium oxide, zinc oxide, iron oxide, calcium oxide, magnesium oxide, zeolite, calcium oxide, and magnesium oxide.

[0039] The polymer compound that is the organic filler may be a linear polymer compound formed by chemically bonding the inorganic filler to a one-dimensional structure in the form of a thread or chain through a chemical reaction such as addition polymerization, condensation polymerization, addition condensation, or covalent bonding, or a network polymer compound having a three-dimensional structure in which the inorganic filler is bonded by a covalent bond or the like. The inorganic filler used in the electrodes is an inorganic compound in which copper, silver, silicon, etc. are chemically bonded to oxygen, hydrogen, carbon, etc., and is based on a metal atom that has electrical conductivity and thermal conductivity, and those having siloxane bonds, etc. are particularly preferred. Organic fillers include polymers with urethane bonds such as polyurethane, which are usually produced by polyaddition of compounds with isocyanate groups and hydroxyl groups, and have urethane (-NH CO O-) bonds; synthetic resins made from polymers of acrylic acid esters or methacrylic acid esters, such as urethane rubber acrylic resins; and polymeric compounds with amide bonds (the same bonds as proteins).

[0040] The shape of the filler is preferably spherical, flat, needle-like, or polygonal, and the particle size is preferably 0.1 μm to several tens of μm.

[0041] Binders that can be used for electrodes include thermosetting resins, photocurable resins, and thermoplastic resins.

[0042] Thermosetting resins are resins that are in a state before chemical reactions such as addition polymerization, condensation polymerization, covalent bonding of the organic fillers, and are made from relatively low molecular weight substances that become three-dimensional cross-linked polymer structures (network structures) when heated, such as phenolic resins, amino resins, unsaturated polyester resins, epoxy resins, and silicone rubber.Once hardened, these resins will not soften again even when heated. Thermosetting resins react at temperatures ranging from room temperature to high temperatures, and react through addition polymerization, condensation polymerization, addition condensation, covalent bonding, and other processes. For example, elastomers such as silicone rubber are primarily made from polyorganosiloxane (silicone polymer), which has a polymer backbone (main chain) consisting of siloxane bonds (Si-O-) in which silicon and oxygen atoms are arranged alternately. They can be divided into HTV (High Temperature Vulcanizing Rubber), LTV (Low Temperature Vulcanizing Rubber), and RTV (Room Temperature Vulcanizing Rubber). HTV cures at temperatures above 140°C, LTV at 40-140°C, and RTV at 0-40°C. However, due to diversification, the distinction between HTV and LTV has become blurred, and they are often simply divided into heat-curing and room-temperature-curing types. Furthermore, depending on the properties before curing, they can be divided into solid millable types (HCR; High Consistency Rubber) and liquid types, with the liquid type including LSR (Liquid Silicone Rubber) and RTV product groups. HCR uses a linear gum with a degree of polymerization of about 5000 to 10,000, while liquid silicone rubber (LSR, RTV) is primarily composed of a linear polymer with a degree of polymerization of about 100 to 2000. Furthermore, depending on the crosslinking mechanism, they can be classified as peroxide curing, addition reaction curing, or condensation reaction curing. Photocurable resins are resins that polymerize and harden when exposed to light of a specific wavelength. In other words, binders are thermosetting resins, photocurable resins, thermoplastic resins, etc. before the chemical reaction or bonding or adhesion described above.

[0043] As the binder to be used for the electrodes, resins having rubber elasticity and porous properties can be used, such as polyurethane-based thermoplastic elastomers, which are block copolymers having urethane bonds, thermoplastic polyurethanes, thermosetting urethane elastomers, polyester-based elastomers consisting mainly of acrylic rubber and polypropylene, polyester, and thermoplastic elastomers having block copolymers of methyl methacrylate and butyl acrylate. It is even more preferable to use a material containing siloxane. Siloxane refers to a polymer formed by alternating bonds between silicon (Si) and oxygen (O), and is the main skeleton of silicone, called a siloxane bond. In particular, silicone elastomers with a siloxane compound skeleton are highly effective in further enhancing the flexible or stretchable characteristics of electrodes.

[0044] The wiring pattern printing ink capable of forming electrodes usable in this embodiment is defined based on a completely different concept from printing inks used in general printing applications. General printing inks are used by mixing components with a small difference in solubility parameter (hereinafter abbreviated as SP value) with respect to the binder contained in the printing ink. Two components with a small difference in SP value are easily mixed (high solubility), and therefore can ensure ease of handling during printing, smoothness of the printed material, adhesion to the printed material, etc.

[0045] However, in the present invention, unlike the concept of general printing inks, by using an additive with a large difference in SP value from the inorganic filler or organic filler and / or binder contained in the printing ink, in this embodiment, it becomes possible to cause the additive to ooze out as a lubricant due to the filling pressure.

[0046] As mentioned above, when a silicone elastomer with a siloxane compound skeleton is used as the binder for a printing ink, it is preferable to use a water-soluble solvent as an additive because it is water-insoluble. Furthermore, because the elastomer has rubber elasticity and porosity, the water-soluble solvent penetrates and impregnates the porous interior. When such a printing ink is used for printing, the impregnated additive seeps out due to the pressure and shear applied to the printing ink, forming a film at the interface between the plate and the printing ink, which acts as a lubricant and easily exhibits slipperiness.

[0047] An example of the composition of the printing ink used in this embodiment is a composition that uses a conductive material such as silver or carbon as a filler, a silicone polymer as a binder, a main solvent (for example, a chain siloxane such as dimethylsiloxane or dodecamethylpentasiloxane, or a cyclic siloxane such as octadecamethylcyclononasiloxane) or normal undecane or other solvents mainly containing aliphatic hydrogen, etc., as the main component, and additives are added. In this case, since the binder is water-insoluble, the additives are water-soluble.

[0048] The printing ink used in this embodiment will be described using a mixture of rubber (binder) and oil (additive) as an example. When rubber (binder) and oil (additive) are mixed, the rubber swells. This is a phenomenon in which the oil penetrates between the rubber molecules; if the oil (additive) mixes easily with the rubber (binder), it will swell; if it does not mix easily, it will not swell easily. Even if it penetrates between the rubber (binder) molecules, it will seep out onto the rubber surface under conditions such as compression. In other words, if the binder of the printing ink is water-insoluble, adding a water-soluble solvent additive will create a condition in which the water-soluble solvent additive seeps out onto the surface of the printing ink, since substances with different polarities or large differences in SP values ​​are difficult to mix with each other.

[0049] When the binder of the printing ink is water-soluble, a water-insoluble solvent is used as an additive. Then, by the same mechanism as above, the water-insoluble solvent seeps onto the surface of the printing ink and acts as a lubricant.

[0050] The main solvent and additives used in printing inks can be either water-insoluble or water-soluble. Generally, the solvent contained in printing inks used as fillers or in printing methods is a composition containing a compound represented by the following structural formula (1) (excluding monohydroxystearic acid). [C1] R1-CH2-R2 (1) (wherein R1 represents a monohydroxyalkyl group, and R2 represents a carboxyl group (C(=O)OH) or an amide group (C(=O)NH2))

[0051] Specific examples of solvents include n-heptane (SP value: 7.3), 2-(2-ethoxyethoxy)ethyl acetate (SP value: 9.0), ethylene glycol monoethyl ether acetate (SP value: 8.8), n-propanol (SP value: 11.8), 1,2,5,6-tetrahydrobenzyl alcohol (SP value: 11.3), diethylene glycol ethyl ether (SP value: 10.9), 3-methoxybutanol (SP value: 10.9), triacetin (SP value: 10.2), propylene glycol monomethyl ether (SP value: 10.2), cyclohexane (SP value: 10.2), and cyclohexane (SP value: 10.2). Pentanone (SP value: 10.0), γ-butyrolactone (SP value: 9.9), cyclohexanone (SP value: 9.9), propylene glycol-n-propyl ether (SP value: 9.8), propylene glycol-n-butyl ether (SP value: 9.7), dipropylene glycol methyl ether (SP value: 9.7), 1,4-butanediol diacetate (SP value: 9.6), 3-methoxybutyl acetate (SP value: 8.7), propylene glycol diacetate (SP value: 9.6), lactic acid ethyl acetate (SP value: 9.6), ε-capric triglyceride Lactone (SP value: 9.6), 1,3-butylene glycol diacetate (SP value: 9.5), dipropylene glycol-n-propyl ether (SP value: 9.5), 1,6-hexanediol diacetate (SP value: 9.5), dipropylene glycol-n-butyl ether (SP value: 9.4), tripropylene glycol methyl ether (SP value: 9.4), tripropylene glycol-n-butyl ether (SP value: 9.3), undecane (SP value: 15.8), decane (SP value: 15.8), dodecane (SP value: 16.0), cyclohexane ... Chlorohexanol acetate (SP value: 9.2), diethylene glycol monoethyl ether acetate (SP value: 9.0), ethylene glycol methyl ether acetate (SP value: 9.0), diethylene glycol monobutyl ether acetate (SP value: 8.9), ethylene glycol monobutyl ether acetate (SP value: 8.9), methyl acetate (SP value: 8.8), ethyl acetate (SP value: 8.7), propylene glycol monomethyl ether acetate (SP value: 8.7), n-propyl acetate (SP value: 8.Examples of suitable acrylic acid esters include propylene glycol methyl ether acetate (SP value: 8.7), 3-methoxybutanol acetate (SP value: 8.7), butyl acetate (SP value: 8.7), isopropyl acetate (SP value: 8.5), tetrahydrofuran (SP value: 8.3), dipropylene glycol methyl n-butyl ether (SP value: 8.0), dipropylene glycol methyl n-propyl ether (SP value: 8.0), dipropylene glycol dimethyl ether (SP value: 7.9), propylene glycol methyl n-butyl ether (SP value: 7.8), propylene glycol methyl n-propyl ether (SP value: 7.8), and dimethylsiloxane (SP value: 7.5). In the present invention, the SP value is merely a reference for selecting a solvent, and what is important is determining whether the solvent is water-soluble or water-insoluble, and then combining it with a solvent that is the exact opposite of the main solvent.

[0052] Regarding the definitions of water-soluble and water-insoluble, the following is the definition for water-soluble liquids in Class 4 hazardous materials. Class 4 hazardous materials are flammable liquids. They are further divided into (a) those that dissolve in water (water-soluble) and (b) those that do not dissolve in water (water-insoluble). These are defined by government ordinance as follows: A water-soluble liquid is one that maintains a uniform appearance when mixed with an equal volume of pure water at 1 atmosphere and 20°C, while a water-insoluble liquid is any liquid other than a water-soluble liquid. A water-insoluble liquid separates into two layers when mixed with water. If the liquid's specific gravity is lower than that of water, a water-insoluble layer will form above the water layer, and if it is higher, a water-insoluble layer will form below the water layer. In the case of water-soluble liquids, when mixed, the layers will become uniform without separating. Some liquids are slightly soluble in water, such as diethyl ether, a special flammable substance, and ethyl acetate, a first-class petroleum product, but by definition they are classified as water-insoluble.

[0053] Therefore, based on the above definition, The water-soluble solvents were 2-(2-ethoxyethoxy)ethyl acetate (SP value: 9.0), ethylene glycol monoethyl ether acetate (SP value: 8.8), n-propanol (SP value: 11.8), 1,2,5,6-tetrahydrobenzyl alcohol (SP value: 11.3), diethylene glycol ethyl ether (SP value: 10.9), 3-methoxybutanol (SP value: 10.9), propylene glycol monomethyl ether (SP value: 10.2), γ-butyrolactone (SP value: 9.9), propylene glycol-n-propyl ether (SP value: 9.8), dipropylene glycol methyl ether (SP value: 9.7), ethyl lactate acetate (SP value: 9.6), and ε-caprolactone. (SP value: 9.6), tripropylene glycol methyl ether (SP value: 9.4), tripropylene glycol-n-butyl ether (SP value: 9.3), diethylene glycol monoethyl ether acetate (SP value: 9.0), ethylene glycol methyl ether acetate (SP value: 9.0), diethyl ether acetate (SP value: 9.0), tetrahydrofuran (SP value: 8.3), dipropylene glycol methyl-n-butyl ether (SP value: 8.0), dipropylene glycol methyl-n-propyl ether (SP value: 8.0), dipropylene glycol dimethyl ether (SP value: 7.9), propylene glycol methyl-n-propyl ether (SP value: 7.8).

[0054] The non-water-soluble solvents were undecane (SP value: 15.8), decane (SP value: 15.8), dodecane (SP value: 16.0), triacetin (SP value: 10.2), cyclopentanone (SP value: 10.0), cyclohexanone (SP value: 9.9), propylene glycol-n-butyl ether (SP value: 9.7), 1,4-butanediol diacetate (SP value: 9.6), 3-methoxybutyl acetate (SP value: 8.7), propylene glycol diacetate (SP value: 9.6), 1,3-butylene glycol diacetate (SP value: 9.5), dipropylene glycol-n-propyl ether (SP value: 9.5), 1,6-hexanediol diacetate (SP value: 9.5), dipropylene glycol-n-butyl ether (SP value: 9.4), Cyclohexanol acetate (SP value: 9.2), diethylene glycol monobutyl ether acetate (SP value: 8.9), ethylene glycol monobutyl ether acetate (SP value: 8.9), methyl acetate (SP value: 8.8), ethyl acetate (SP value: 8.7), propylene glycol monomethyl ether acetate (SP value: 8.7), n-propyl acetate (SP value: 8.7), dipropylene glycol methyl ether acetate (SP value: 8.7), 3-methoxybutanol acetate (SP value: 8.7), butyl acetate (SP value: 8.7), isopropyl acetate (SP value: 8.5), propylene glycol methyl-n-butyl ether (SP value: 7.8), and dimethylsiloxane (SP value: 7.5).

[0055] When the total weight of the filler and binder contained in the printing ink used in this embodiment is 100 parts, the filler may be 50 to 99.9 parts. Specifically, the main component may be a filler, a silver paste, a copper paste, or the like used for printing purposes.

[0056] The additives for printing ink are preferably adjusted in the range of 0.1 to 50 parts, assuming that the total weight of the filler and binder contained in the coating agent is 100 parts.

[0057] The printing ink used in this embodiment may contain a compatible solvent that has good affinity with the binder. The presence of a compatible solvent makes it possible to ensure adhesion, conductivity, electrical continuity, etc. between the inorganic filler or the mixture of organic filler and binder (base) and the printed material. This is because slipperiness can be obtained while maintaining these properties. If the amount added is outside the above range, the chemical bonds of the base elastomer, etc., may be damaged or separated, making the ink physically brittle and making printing difficult. Even if printing is possible, there may be a loss of elasticity or a significant loss of electrical conductivity and thermal conductivity.

[0058] The printing ink used in this embodiment has the effect of causing the lubricant in the coating material to ooze out when pressure is applied to the printing ink during squeegee sweeping, which promotes peeling of the coating material from the mask interface and allows the coating material to be transferred to the substrate without cohesive failure, resulting in wiring electrodes with a roughly rectangular cross section and opposing side surfaces that rise almost vertically.

[0059] <Flexible or stretchable sheet> The flexible or stretchable sheet used as the substrate for pattern printing according to the present invention will now be described.

[0060] Flexible or stretchable sheets that can be used in this embodiment include OPP (biaxially oriented polypropylene), CPP (non-oriented polypropylene), HDPE (high density polyethylene), MDPE (medium density polyethylene), LDPE (low density polyethylene), L-LDPE (linear low density polyethylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), O-NY (nylon), PA (polyamide), EVAC (EVA resin), PVC (polyvinyl chloride), SAN (AS resin), ABS (ABS resin), PMMA (methacrylic resin), PVAL (polyvinyl alcohol), PVDC (vinylidene chloride resin), PC (polycarbonate), POM (acetal resin), PBT (polybutylene terephthalate), PTFE (fluororesin), PF (phenolic resin), MF (melamine resin), UF (urea resin), PUR (polyurethane), EP (epoxy resin), UP (unsaturated polyester resin), PS (polystyrene), KOP (polyvinylidene chloride coated OPP), AL (aluminum foil), AOP (PVA coated OPP / Tocello), PT, MST, Kcello (cellophane), VM (aluminum vapor deposition film, transparent vapor deposition film), co-extrusion film, nonwoven fabric, NR (natural rubber), IR (isoprene rubber), BR (butadiene rubber), SBR (styrene-butadiene rubber), IIR (butyl rubber), NBR (nitrile rubber), EPM, EP, EPDM (ethylene-propylene rubber), CR (chloroprene rubber), ACM, It is made up of materials such as ANM (acrylic rubber), CSM (chlorosulfonated polyethylene rubber), PUR, U (urethane rubber), Si, Q, VMQ, SR (silicone rubber), FKM, FPM (fluororubber), EVA (ethylene vinyl acetate rubber), CO, ECO (epichlorohydrin rubber), T (multi-flow rubber), and copper foil, and can be used in the form of a single layer or a laminated film of two or more layers. In the following disclosure, when a flexible sheet is mentioned, the flexible sheet can be replaced with a stretchable sheet unless there is a special reason.

[0061] <Resistor> Next, the resistor used in this embodiment will be described.

[0062] The resistor that can be used in this embodiment is a resistor layer made of a conductive organic adhesive that is made of a mixture of a filler and a binder and a solvent for the binder, and that has been dried, heat-cured, photo-cured, etc. Examples of the conductive organic adhesive that can be used include acrylic adhesives, epoxy adhesives, polyester adhesives, polyurethane adhesives, silicone adhesives, and polyimide adhesives. As the conductivity imparting agent, conductive particles such as carbon black particles and graphite particles can be blended, and carbon paste having PTC characteristics (positive temperature coefficient) is particularly preferred. As the application method, a doctor blade method, screen printing method, spray application method, etc. can be used.

[0063] PTC stands for Positive Temperature Coefficient Thermal Resistor, and refers to the characteristic of a material's electrical resistance increasing rapidly at a certain temperature. This characteristic is known as a "positive temperature coefficient." In other words, materials with a high PTC have the property of making electrical flow more slowly as the temperature rises and more easily as the temperature drops. By utilizing this characteristic in heaters, even if only a portion of the heater becomes abnormally hot, heat generation in that portion can be suppressed, reducing unnecessary power consumption. Conversely, at low temperatures, electrical flow is facilitated due to low resistance. However, at a certain temperature, resistance rises rapidly and electrical flow ceases. The temperature at which this occurs is called the Curie point. The Curie point varies depending on the material, but is typically in the range of -50°C to 150°C. Therefore, even when the heater of the present invention is incorporated into a flexible or stretchable sheet for an actuator, safety against fire and other issues is ensured.

[0064] <Insulating coating material> The insulating coating material used in this embodiment will be described.

[0065] The insulating coating material that can be used in this embodiment is preferably made of a material that has sufficient heat resistance to prevent deterioration in strength, deformation, melting, deterioration, combustion, etc., during the desired usage period. For example, a sheet made of a polyester resin such as polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, ethylene-terephthalate-isophthalate copolymer, or polyarylate can be used, preferably a biaxially oriented sheet. Alternatively, a resin sheet made of a fluororesin such as polyvinyl fluoride, polyvinylidene fluoride, polyethylene tetrafluoroethylene, or ethylene-tetrafluoroethylene copolymer, a polyimide resin, or RTV silicone rubber can also be used. To impart flame retardancy, a flame retardant such as aluminum hydroxide, magnesium hydroxide, molybdenum oxide, or diantimony trioxide may be added to these resins. These insulating coatings can be adhered to the desired area by methods such as heat fusion, dry lamination, spray coating, etc. Alternatively, they can also be coated to the desired area by printing methods such as silk screen printing, gravure printing, flexographic printing, offset printing, and roll transfer printing. The resin binder for the ink used may be, for example, acrylic resin, polyester resin, polyimide resin, silicone resin, etc. The thickness of the insulating coating is preferably generally about 20 to 300 μm. Next, an example for verifying the effect of this embodiment will be described.

[0066] <Printing of wiring electrodes> The substrate was a 200 μm thick silicone-based silicone elastomer film with two layers, a PET film laminated to the backside, and conductive ink (filler: silver, binder: siloxane elastomer) made by Fujikura Kasei Co., Ltd., a stretchable silver paste called "DOTITE (registered trademark) XA-9476" for printing the electrode pattern. The resistor was a carbon-based conductive elastomer made by Wacker Asahi Kasei Co., Ltd., called ELASTOSIL (registered trademark) LR 3162, with a volume resistivity of 80 Ω·cm.

[0067] As an additive to the electrode pattern printing ink, 2-(2-ethoxyethoxy)ethyl acetate (also known as diethylene glycol monoethyl ether acetate), a water-soluble solvent that is incompatible with siloxane elastomer, was prepared and mixed with the electrode pattern printing ink to create a pattern printing ink with slip properties. The printing method used was the screen printing method of the present invention, in which the pattern printing ink having the above-mentioned slipperiness imparted to the screen printing plate was filled into a dispenser syringe, and printing was carried out while the dispenser needle was brought into contact with the screen printing plate.

[0068] 11 is a diagram showing the injection process in the screen printing method of the present invention. First, a 200 μm-thick nickel film was attached to a metal mesh such as nickel to prepare a screen printing plate 603 with holes for the printing pattern. Next, a silicone elastomer film substrate 605 with a thickness of 200 μm was set on the printing stage, and a screen printing plate 603 made of a nickel film with a thickness of 200 μm was placed on top of it so that the nickel film surface and the silicone elastomer film were in close contact with each other.

[0069] Next, an arbitrary tapered needle was attached to the lower end of syringe 604 filled with the above-mentioned pattern printing ink, and this tapered needle was pressed vertically with a constant pressure against the top surface of screen printing plate 603, from the side of metal mesh 602 such as nickel, so that the tip opening of the tapered needle and the screen printing plate were tightly attached with no gaps. In this state, the supply pressure to syringe 604 filled with the above-mentioned pattern printing ink was set to 300 kPa.

[0070] At the same time, syringe 604 was moved in the Y-axis direction at a sweep speed of 20 mm / s over the screen on which the pattern to be printed was formed. After sweeping, syringe 604 was moved a certain distance away from metal mesh 602 and shifted 1 mm in the X-axis direction. Thereafter, syringe 604 was again brought into close contact with metal mesh 602, and syringe 604 was moved in the Y-axis direction again at a supply pressure of 300 kPa and a sweep speed of 20 mm / s. The supply pressure and sweep speed may be adjusted as desired.

[0071] By repeating the above-mentioned procedure, the ink for printing the pattern was injected into the screen holes for the entire pattern to be printed. During this process, the supply pressure, sweep speed, shift length, etc. could be changed as desired depending on the printing conditions.

[0072] 12 is a diagram showing the squeegee sweeping process in the screen printing method of the present invention. When the syringe 604 has completely or partially filled the scattered pattern to be filled, the squeegee 606 is swept at a constant speed and with a constant pressure in the Z-axis direction at an angle of about 60 degrees relative to the surfaces of the screen printing plate 603 and metal mesh 602.

[0073] As a result, a wiring pattern can be printed that has a cross-sectional shape that directly transfers the groove shape formed on the screen printing plate 603, is roughly rectangular, has an electrode width of about 100 μm, a height of about 200 μm, and has a large aspect ratio with roughly vertically cut opposing side surfaces with a large area.

[0074] <Concave> The recesses formed on the electrode surface when screen printing is performed using the printing ink described above will now be described. Figures 13 and 14 are diagrams showing recesses formed in the screen mesh marks when the coating material and printing method according to this embodiment are used.

[0075] When the screen printing plate 610 shown in FIG. 13 is used, the pressure of the squeegee and the pushing back pressure from the substrate 615 occur at the interface H between the filled coating material 611 and the opening 613 of the mask 612 and the screen mesh 614, causing some of the additives in the coating material 611 to seep out to the surface as a lubricant, and the inner wall of the opening 613 of the mask 612, the substrate 615, and the screen mesh 614 are coated with the lubricant. This promotes peeling of the coating material 611 from the mask interface, and the coating material 611 is transferred onto the substrate 615 without causing cohesive failure.

[0076] Furthermore, when a dispenser, for example, is used as the pressurized container for the pressure filling method, coating material leaking from the contact point between the screen printing plate 610 and the tip of the dispenser or from the opening 613 in the mask can be removed from the plate surface and collected by sweeping with a squeegee. When sweeping with the squeegee, some of the additives in the coating material 611 seep out as a lubricant to the intersection with the screen mesh 614, forming recesses 616.

[0077] 14, similar recesses 616 are also formed when a screen printing plate 620 is used in which a metal mask 622 and a metal mesh 624 are bonded together. Hereinafter, the term "screen mesh" includes metal mesh.

[0078] Screen mesh marks are marks left on the surface as unevenness at the intersections of the screen mesh in a printed pattern, where the material has passed through the screen mesh. When conventional coating agents and conventional screen printing are used, cohesive failure occurs, and the above-mentioned kamaboko-shaped convex portions form at the screen mesh marks.

[0079] As a specific example, a case where a screen plate with a mesh wire diameter of 16±2 μm and a side length of the mesh opening of 60±2 μm is used will be explained.

[0080] When the coating material and printing method according to this embodiment were used, the width of the screen mesh marks formed on the pattern surface was 15.8 μm, which was 87.8% to 113% of the mesh wire diameter, and the length of one side of the mesh opening mark was 63 μm, which was 101.6% to 108.6% of the length of one side of the mesh opening in the screen plate.

[0081] In addition, the screen mesh marks showed a gap (height difference) of 3.89 μm between the top (top surface) of the mesh opening marks and the bottom.

[0082] Based on these results, in the screen printing method of the present invention, recesses are generated when the width of the mesh marks is between 10 μm and 40 μm. The opening marks can also be square, with each side measuring between 20 μm and 210 μm. The term "square" here refers not only to cases where the lengths of adjacent sides are perfectly identical, but also to cases where the lengths of adjacent sides differ by approximately ±10%. The mesh portion of the screen printing plate can also have a different shape, such as lines, and in this case, the marks in the areas corresponding to the mesh will also become recesses.

[0083] <Heater element and driving device using the heater element> The heating element and the driving device (actuator) using the heating element according to the present embodiment will be described below using several embodiments. However, it goes without saying that the present invention is not limited to these embodiments. Furthermore, in the description of the drawings, the same reference numerals are used for components that are the same as or equivalent to those already described, and their description will be simplified or omitted.

[0084] [First embodiment] 15 is a diagram showing the heating element and the driving device according to the first embodiment. The first embodiment will be described below in the order of manufacture. First, the base material used in the first embodiment is made by laminating two types of flexible or stretchable sheets 701 and 702 having different linear expansion coefficients. Next, in this embodiment, the positive wiring electrode 703 is arranged in a form surrounded by a U-shaped negative wiring electrode 704. Hereinafter, a wiring pattern formed by a combination of electrodes in which one electrode is U-shaped and the other electrode is surrounded inside the U-shaped electrode will be referred to as a "U-shaped wiring pattern." Also, the U-shaped wiring electrode will be referred to as a "U-shaped side electrode," and the wiring electrode inside the U-shaped side electrode will be referred to as an "inner electrode."

[0085] Next, the resistor 204 is filled into the gap between the opposing positive wiring electrode 703 and negative wiring electrode 704. After that, the positive wiring electrode 703, the negative wiring electrode 704 and the resistor 204 are covered with an insulating covering material 705. As a result, the positive wiring electrode 703, the resistor 204, and the negative wiring electrode 704 are arranged on a plane, and a heat generating portion can be obtained in which these are sandwiched from above and below by the substrate and the insulating layer. If it is desired to thermally isolate the heat generating portion from the surroundings, a cut 706 may be provided in the base material around the periphery of the U-shaped negative wiring electrode 704 . In other words, it is possible to realize a configuration in which the heat generating portion protrudes as a cantilever in the area surrounded by the notch 706 .

[0086] Hereinafter, a divided region in which structural units, each having a resistor sandwiched between the opposing side surfaces of positive and negative wiring electrodes, are continuously repeated in a direction perpendicular to the opposing parallel sides, is referred to as a "heating unit." In this case, the wiring electrode pattern can be specified by the number of positive wiring electrodes and the number of negative wiring electrodes present in one heating unit (hereinafter, positive wiring electrodes or negative wiring electrodes may be simply referred to as positive electrodes or negative electrodes).

[0087] For example, in the wiring pattern (U-shaped wiring pattern) of the first embodiment, there is one heat generating unit, but the wiring pattern can be specified as a combination of one (odd number) positive electrode and two (even number) negative electrodes.

[0088] When specifying the wiring pattern in this way, the combinations of wiring patterns include (a) a combination of an odd number of positive electrodes and an even number of negative electrodes, (b) a combination of an even number of positive electrodes and an odd number of negative electrodes, (c) a combination of an even number of positive electrodes and an even number of negative electrodes, and (d) a combination of an odd number of positive electrodes and an odd number of negative electrodes.

[0089] A heating unit whose wiring electrodes have a U-shaped wiring pattern is sometimes called a "U-shaped heating unit," and the actuator that drives it is sometimes called a "U-shaped actuator."

[0090] [Second embodiment] 16 is a plan view showing a heating element and a driving device according to the second embodiment. The second embodiment is the same as the first embodiment except for the number of electrodes in the wiring pattern. Components that are the same as or equivalent to those in the first embodiment are given the same reference numerals, and their descriptions will be simplified or omitted.

[0091] Wiring pattern 801 is configured by connecting three U-shaped heating units, each of which has a U-shaped wiring pattern. Each U-shaped wiring pattern is composed of two positive wiring electrodes and three negative wiring electrodes. Similarly, each U-shaped wiring pattern in wiring pattern 802 is composed of three positive wiring electrodes and four negative wiring electrodes.

[0092] In the wiring patterns 802 and 803, each heating unit has three negative wiring electrodes connected in series, so the negative side is connected to a common negative terminal 803, and the positive side is connected to three independent positive terminals 804a-c. This makes it possible to apply an arbitrary voltage and change the heat generation and operation of the desired parts using input control such as a sequencer. Furthermore, the notches 805 allow each heating unit to operate as an independent driving device (U-shaped actuator). The terminals are sometimes called driving terminals.

[0093] Increasing the number of wiring electrodes increases the amount of current flowing through each heating unit, and the amount of heat generated also increases. If possible, it is preferable to make the line width of the outermost wiring electrodes wider than the line width of electrodes with fewer numbers.

[0094] <Manufacturing method> The manufacturing method of the second embodiment will be described. First, a wiring pattern 801, which connected three heating units each consisting of two positive electrodes and three negative electrodes, was printed on a substrate using the screen printing method of the present invention. Each electrode had a width of 200 μm and a height of 153 μm, with opposing sides rising approximately vertically, resulting in an electrode with a roughly rectangular cross-sectional area. In this state, the electrode was baked once at 90°C for 30 minutes and then at 160°C for 60 minutes.

[0095] The substrate was prepared by laminating flexible sheets with different thermal linear expansion coefficients, namely, flexible sheet 701 made of a 100 μm thick PET film (linear expansion coefficient: 6.5 (×10-5 / °C)) and flexible sheet 702 made of a 200 μm thick silicone elastomer film (linear expansion coefficient: 40 (×10-5 / °C)).

[0096] As the flexible sheet 702, in addition to silicone, films such as polyurethane (linear expansion coefficient: 20 (×10-5 / °C)) or polyvinylidene chloride (linear expansion coefficient: 19 (×10-5 / °C)) can also be used depending on the application and design. To improve the heat dissipation effect, a metal sheet such as aluminum foil or copper foil may be added to laminate two or more layers of sheets. Alternatively, such a metal sheet can be used instead of PET.

[0097] Next, a high-resistance conductive elastomer with a volume resistivity of 80 Ω cm, ELASTOSIL® LR 3162 manufactured by Wacker Asahi Kasei Co., Ltd., mainly composed of carbon, was injected into the gaps between the two positive electrodes and three negative electrodes as resistor 204. In this way, three resistors 204 were connected together in a 6 mm long filled state along the electrode length direction with the electrode height leveled, and baked at 100°C for 60 minutes.

[0098] Next, the flexible UV photosensitive insulating coating material 705 was coated with KER-4690 (A / B) manufactured by Shin-Etsu Chemical Co., Ltd. to a thickness of about 10 microns, and cured with UV light having a wavelength of 365 nanometers.

[0099] Similarly, the wiring pattern 802 shown in FIG. 16, which is made up of three U-shaped heating units each consisting of three positive electrodes and four negative electrodes, was also subjected to UV curing treatment by the same method.

[0100] Next, in wiring patterns 801 and 802, a total of four incisions 805 were made with a cutter between and on the outside of the three connected heating units, penetrating all the way to the back of the substrate, and further incisions 706 were made perpendicular to incisions 805 to separate the head side of the heating units into three, thereby forming heating elements each consisting of three independent heating units.

[0101] <Actions and Effects> To observe the operation of one heating unit, a DC voltage of 5 V was applied to the positive terminal 804a and the negative terminal 803, and the temperature rise was monitored with a thermocouple fixed on the resistor 204 with polyimide tape.

[0102] FIG. 17 is a comparison graph of the temperature rise of a heating element using the wiring electrode pattern according to the present invention and a heating element using conventional wiring electrodes. The heating element according to the present invention is made up of wiring patterns 801 and 802, while the conventional heating element is made up of wiring pattern 801 printed by screen printing, which is used in conventional electrode printing.

[0103] As can be seen from Figure 17, the temperature of all three heating elements formed this time stopped rising once it reached a certain temperature. Therefore, it can be seen that these heating elements have PTC characteristics.

[0104] In addition, in a comparison with wiring pattern 801, the heating element formed by the screen printing method of the present invention, which has wiring electrodes with an electrode width of 200 μm and a height of 153 μm with opposing sides standing approximately vertically, showed a steep temperature rise of 60°C after 10 seconds of application, and showed a temperature of 76.9°C after 120 seconds with PTC characteristics, but the heating element formed by the conventional screen printing method, which has wiring electrodes with an electrode width of 200 μm and a height of 12 μm and a kamaboko-shaped cross section, showed a much slower temperature rise of 24.6°C after 10 seconds of application, and showed a low temperature of 26.4°C after 120 seconds with PTC characteristics.

[0105] Comparing wiring patterns 801 and 802, they showed roughly the same steep temperature rise of 60°C and 60.1°C, respectively, after 10 seconds of application. However, the temperature after 120 seconds under PTC characteristics was 76.9°C for wiring pattern 801 and 83°C for wiring pattern 802, a difference of about 6°C. This difference is presumably due to the increase in the number of positive and negative electrodes by one each. In other words, the heating element of this embodiment allows the amount of heat generated under PTC characteristics to be controlled by the number of electrodes.

[0106] Furthermore, in wiring pattern 802, an object that could be seen to move was placed on the tip of the heating unit, and when a DC voltage of 5 V was applied to the positive terminal 804a and the negative terminal 803 and the unit was turned on and off, the heating unit was confirmed to warp by about 2 mm over a stroke of 5 seconds. In this way, a quick driving device (actuator) that warps with bimetal-like behavior was created.

[0107] [Application Example 1 of the Second Embodiment] 18 is a plan view of an LED flicker 806 to which the second embodiment is applied. Descriptions of components that are the same as or equivalent to those in the second embodiment will be simplified or omitted.

[0108] One terminal of the LED chip 807 is attached to the tip of the U-shaped actuator with conductive adhesive, and a wire of the opposite polarity to the attached one (negative if it is positive) is placed so that it contacts the other terminal of the LED chip that is not attached, and a notch is made around each U-shaped actuator to create a circuit. The wiring resistance can be adjusted so that a typical LED rated current of 20 mA flows.

[0109] The heating element side is forcibly warped slightly upward by about 1 mm, creating a state where it is not electrically connected to the opposite side. When electricity is applied to the circuit, no current initially flows through the LED, but as the heating element heats up, the forcibly warped part by about 1 mm bends downward, establishing electrical continuity with the wiring arranged on the opposite side. This causes current to flow to the opposite side and the LED lights up. The amount of current flowing through the heating element then decreases, causing the heating element temperature to drop, which causes the downward bending to return to an upward position, cutting off the current to the LED and turning it off. This again increases the amount of current to the heating element, causing it to bend downward even more, and the LED lights up. This action is automatically repeated to create an automatic flashing device (flicker).

[0110] [Application Example 2 of Second Embodiment] 19 is a plan view of a butterfly device 808 to which the second embodiment is applied. Descriptions of components that are the same as or equivalent to those in the second embodiment will be simplified or omitted. By connecting multiple U-shaped actuators and symmetrically arranging blocks with notches around the U-shaped actuators, it becomes possible to operate each actuator independently. This enables flapping movements like a butterfly or dragonfly, or walking movements like a centipede. Furthermore, by incorporating variations in the wiring pattern, it is possible to add twists to each actuator, enabling more complex flapping and walking movements.

[0111] [Third embodiment] An embodiment of the present invention is shown in which an electrode pattern is arranged in a circle as an actuator in which a plurality of U-shaped wiring patterns are connected. In this embodiment, arranging in a circular shape means that the longitudinal directions of the U-shaped wiring patterns are arranged at approximately equal intervals in the radial direction from the center of the circle to the outer periphery, and the patterns are arranged so that they form a circle as a whole.

[0112] In the first place, when arranging eight U-shaped wiring patterns evenly on a circle, if lead wires and terminals are provided in one-to-one correspondence with the U-shaped side electrodes and inner electrodes of each U-shaped wiring pattern, 8 x 2 = 16 terminals are required, which is a large number of terminals, and there is also the problem that the positive or negative lead wires cannot be drawn from the center of the pattern to the outside on a single substrate.

[0113] FIG. 20 is a plan view showing a heating element and a driving device according to the third embodiment.

[0114] In the circular wiring pattern 1001 of this embodiment, for example, terminal 1001e can be connected to a connecting portion 1001e(X) where the U-shaped side electrodes of adjacent U-shaped wiring patterns are joined. Terminal 1001f can also be connected to a connecting portion 1001f(X) where the inner electrodes of adjacent U-shaped wiring patterns are joined. Of the two U-shaped side electrodes joined to connecting portion 1001e(X), one positioned clockwise faces the other, and of the two inner electrodes joined to connecting portion 1001f(X), one positioned counterclockwise faces the other, forming a heating unit.

[0115] Similarly, of the two U-shaped side electrodes joined to the connecting portion 1001g(X), the one positioned counterclockwise faces the one of the two inner electrodes joined to the connecting portion 1001f(X), which faces the one positioned clockwise faces each other to form a heating unit.

[0116] In this way, the positive and negative poles are shifted in phase by one pair, as if joining hands in a circle. A resistor is inserted into the gap between the positive and negative wiring electrodes of each U-shaped wiring pattern to form a heating unit. The wiring electrodes and resistor are covered with an insulating coating, and there is a U-shaped notch 706 on the outer periphery of each U-shaped wiring pattern.

[0117] Next, a DC voltage of 5 V was applied to the positive terminal 1001e and the negative terminal 1001f. In this case, only resistor 1002ef generates heat. To heat only resistor 1002fg on the clockwise adjacent U-shaped pattern, a DC voltage of 5V is applied to terminal 1001f negative and terminal 1001g positive.

[0118] In this manner, by shifting the 5V application in the order of terminal 1001g positive electrode, terminal 1001h negative electrode, terminal 1001a positive electrode, terminal 1001b negative electrode, terminal 1001c positive electrode, terminal 1001d negative electrode, and terminal 1001e positive electrode, the U-shaped wiring patterns arranged in a circle became an actuator that warped the outer edge of the circle clockwise one by one. Therefore, depending on the combination of voltages applied to each, it can be made into an actuator that can warp in the opposite direction, halfway, at 45-degree intervals, or in any combination of warping patterns.

[0119] In this embodiment, a drive terminal of a first polarity (meaning positive or negative) is adjacent to a drive terminal of a second polarity of the opposite polarity ("adjacent" includes the relationship between drive terminals placed at both ends). The drive terminals of the first polarity are connected to wiring electrodes in the U-shaped wiring pattern of adjacent clockwise and counterclockwise U-shaped heat generating units, and the drive terminals of the second polarity are connected to wiring electrodes in the U-shaped wiring pattern of adjacent clockwise and counterclockwise U-shaped heat generating units, so that the clockwise wiring electrode connected to the drive terminal of the first polarity and the counterclockwise wiring electrode connected to the drive terminal of the second polarity constitute wiring electrodes facing each other in the same U-shaped wiring pattern.

[0120] [Fourth embodiment] The third embodiment uses a circular actuator with a pattern in which the outside of the circle is deflected every 45 degrees of phase, but a pattern in which the inside of the circle is deflected every 45 degrees of phase has also been realized.

[0121] FIG. 21 is a plan view showing a heating element and a driving device according to the fourth embodiment.

[0122] The circular wiring pattern 1101 has an appearance of a circle of fan-shaped heat generating units arranged in a circle, with the central angle of the circle divided into approximately equal parts (for example, approximately six equal parts). The wiring pattern in each heat generating unit is arranged, for example, along the arc shape that is the outer periphery of the fan, with positive and negative wiring electrodes alternately arranged in a comb shape from near the center to near the periphery, with a certain gap between them (hereinafter referred to as a "fan-shaped wiring pattern"). Resistors are inserted into the gaps to form the heat generating units (hereinafter referred to as "fan-shaped heat generating units"). An even number of heat generating units is desirable, but this is not limited to this.

[0123] According to this embodiment, for example, the positive electrodes of two adjacent heating units can be connected to a connecting portion 1101d(Y) near the maximum arc of the sector from terminal 1101d, and the negative electrodes of two adjacent heating units can be connected to a connecting portion 1101c(Y) near the maximum arc of the sector from terminal 1101c.

[0124] In this manner, one terminal is connected to the positive or negative wiring electrodes of two adjacent heating units via a connecting portion near the largest arc of the fan-shaped circle. For example, positive and negative electrodes are arranged alternately next to each other, such as positive terminal 1101d, negative terminal 1101c, positive terminal 1101b, negative terminal 1101a, positive terminal 1101h, negative terminal 1101g, positive terminal 1101f, and negative terminal 1101e. Resistors are inserted into the gaps between the positive and negative wiring electrodes of each fan-shaped wiring pattern to form a heating unit. An insulating coating covers the wiring electrodes and resistors, and there are notches 1103 radially extending from the center of the circle.

[0125] Next, a DC voltage of 5 V was applied to the terminal 1101d as the positive electrode and the terminal 1101c as the negative electrode. In this case, only resistor 1102cd on the fan-shaped pattern generates heat, and to generate heat only in resistor 1102bc on the adjacent fan-shaped pattern clockwise, a DC voltage of 5V is applied to terminal 1101c as the negative electrode and terminal 1101b as the positive electrode.

[0126] In this manner, by shifting the application of 5V in the order of terminal 1101b positive electrode, terminal 1101a negative electrode, terminal 1101h positive electrode, terminal 1101g negative electrode, terminal 1101f positive electrode, terminal 1101e negative electrode, and terminal 1101d positive electrode, the fan-shaped blocks arranged in a circle became actuators that bent the circle inward one by one in a clockwise direction.

[0127] This is because the sector-shaped interdigital electrode is formed with a longer arc at the outer edge of the circle, and therefore the heat generating area of ​​the resistor is larger there, and the amount of distortion at the outer edge, which generates more heat than the central part of the arc, is greater, and the central part can bend significantly starting from the outer heat generating part.

[0128] Therefore, similar to the third embodiment, by combining the voltages applied to each, the actuator can bend in the opposite direction, bend halfway, bend in 45-degree increments, or create any combination of bending patterns.

[0129] In this embodiment, a drive terminal of a first polarity (meaning positive or negative) is adjacent to a drive terminal of a second polarity of the opposite polarity ("adjacent" also includes the relationship between drive terminals placed at both ends). The drive terminal of the first polarity is connected to the wiring electrodes in the fan-shaped wiring pattern of the fan-shaped heat generating units arranged clockwise and counterclockwise adjacent to each other, and the drive terminal of the second polarity is connected to the wiring electrodes in the fan-shaped wiring pattern of the fan-shaped heat generating units arranged clockwise and counterclockwise adjacent to each other, and the clockwise wiring electrode connected to the drive terminal of the first polarity and the counterclockwise wiring electrode connected to the drive terminal of the second polarity constitute opposing wiring electrodes in the same fan-shaped wiring pattern.

[0130] [Fifth embodiment] The fifth embodiment differs from the first to fourth embodiments in that the driving device is driven by the vapor pressure generated when a liquid is heated and vaporized by a heating element according to this embodiment. In the following description, the same or equivalent components as those in the above embodiments are designated by the same reference numerals, and their description will be simplified or omitted.

[0131] One example of an application field of this embodiment is a rewritable Braille display device. Conventionally, as disclosed in Japanese Patent Application Laid-Open No. 2-160278, a device that displays Braille characters by moving a movable iron core up and down using the electromagnetic attraction force of a solenoid, and as disclosed in Japanese Patent Application Laid-Open No. 10-74039, a device that displays Braille characters by using heat and expansion caused by light supplied from an optical semiconductor laser light source, have been known. However, these devices have problems with the size and operating noise of the solenoid, the size and cost of the optical semiconductor laser light source assembly, etc. In contrast, this embodiment allows for space-saving, quiet operation, and low-cost drive, and is therefore potentially applicable to rewritable Braille display devices, angle adjustment devices for polarizing plates, etc.

[0132] <Balloon capillary> 22 is a longitudinal cross-sectional view of a balloon capillary 1200 according to a fifth embodiment. The "balloon capillary 1200" comprises a balloon portion 1201 and a capillary portion 1202, and the end of the capillary portion 1202 opposite the balloon portion 1201 is closed and sealed. The capillary portion 1202 is filled with a low-boiling-point solvent that vaporizes or thermally expands at a low boiling point of approximately 70 to 120 degrees Celsius. The low-boiling-point solvent is preferably an organic solvent such as ethanol, or a fluorine-based inert liquid that is safer and less corrosive. Note that the liquid may not be illustrated for convenience.

[0133] <Material> Materials for the balloon portion or capillary portion that can be used in this embodiment include CPP (non-oriented polypropylene), HDPE (high density polyethylene), MDPE (medium density polyethylene), LDPE (low density polyethylene), L-LDPE (linear low density polyethylene), PET (polyethylene terephthalate), PEN (polyethylene naphthalate), O-NY (nylon), PA (polyamide), EVAC (EVA resin), PVC (polyvinyl chloride), SAN (AS resin), ABS (ABS resin), PMMA (methacrylic resin), PVAL (polyvinyl alcohol), PVDC (vinylidene chloride resin), PC (polycarbonate), POM (acetal resin), PBT (polybutylene terephthalate), and PTFE (fluororesin). , PF (phenolic resin), MF (melamine resin), UF (urea resin), PUR (polyurethane), EP (epoxy resin), UP (unsaturated polyester resin), PS (polystyrene), KOP (polyvinylidene chloride coated OPP), AL (aluminum foil), A-OP (PVA coated OPP / Tocello), PT, MST, Kcello (cellophane), VM (aluminum vapor deposition film, transparent vapor deposition film), co-extrusion film, NR (natural rubber), IR (isoprene rubber), BR (butadiene rubber), SBR (styrene-butadiene rubber), IIR (butyl rubber), NBR (nitrile rubber), EPM, EP, EPDM (ethylene-propylene rubber), CR (chloroprene rubber), ACM, Materials available include ANM (acrylic rubber), CSM (chlorosulfonated polyethylene rubber), PUR, U (urethane rubber), Si, Q, VMQ, SR (silicone rubber), FKM, FPM (fluororubber), EVA (ethylene vinyl acetate rubber), CO, ECO (epichlorohydrin rubber), and T (polysulfide rubber), and can be processed into single-layer or multi-layer films or tubes. In particular, the use of VM (aluminum vapor deposition film, transparent vapor deposition film), which has gas barrier properties, allows the gas enclosed within the balloon to be maintained for long periods of time. The use of these materials can provide elasticity and flexibility.

[0134] <Manufacturing method> An example of a method for manufacturing the balloon capillary 1200 of this embodiment will be described. A polyolefin heat-shrinkable tube with a diameter of approximately 1.2 mm was prepared, and the entire tube was heated with a burner until it shrunk to a diameter of approximately 0.5 mm. One end of the tube was then clamped with a hot iron and welded to prevent air leakage. A pinpoint area near the welded tube was heated with a burner to melt it, and compressed air was sent instantaneously from the other open end of the tube, causing the melted portion to expand into a balloon portion 1201 with a diameter of 3 mm (inflation method). As the tube expanded, the film on the balloon portion 1201 became thinner, achieving a thickness suitable for repeated expansion and contraction.

[0135] The inflation method is generally a type of extrusion molding, specialized for molding resin (plastic) bag-shaped films, in which molten resin is extruded into a thin film from a ring-shaped die, and at the same time, cold air is blown in to expand it to a certain size to form a bag-like shape. In addition to single-layer films, multi-layer films can also be molded by co-extrusion.

[0136] Next, a beaker filled with ethanol was prepared, and the processed tube was immersed in the ethanol. After making sure that the other end of the opened tube was not exposed to the liquid surface, the beaker was placed in a vacuum degassing device, and a vacuum of 0.1 MPa was created. It was confirmed that all the air in the tube in the beaker had been released. Next, the vacuum was returned to atmospheric pressure, and the ethanol was filled into the tube.

[0137] Next, the tube filled with ethanol was taken out, and with the balloon portion 1201 crushed with a clip, the other open end of the tube was clamped with a hot iron and sealed to form a capillary portion 1202. At this time, the balloon remained in a crushed or deflated state.

[0138] <Balloon drive unit> The balloon capillary 1200 is fixed to the heating unit according to the present invention. In this disclosure, the combination of one heating unit and the balloon capillary fixed thereto is referred to as a "balloon driving unit." Figure 23 is a schematic diagram of an example of a balloon driving unit 1203. The balloon capillary 1200 is fixed to the heating unit 1204, which has the positive wiring electrode 703, the negative wiring electrode 704, and the resistor 204 similar to those in Figure 15, so that the end of the capillary portion 1202 opposite the balloon portion 1201 is in close contact with the heating unit 1204. Fixing is performed using a UV-curable resin or the like. The substrate 1205 is a resin substrate. In this embodiment, the notch 1206 is provided for heat dissipation.

[0139] <How it works> The method of driving the balloon driving unit 1203 will now be described. FIG. 24 is a schematic diagram showing how the balloon driving unit 1203 is driven. A resin base material with a film thickness of 200 μm was used as the base material 1205, and the heating unit 1204 was made up of electrodes and resistors similar to those in the second embodiment. The heating unit 1204 was fixed to the capillary tube portion 1202 near the end of the capillary tube portion 1202 opposite the balloon portion 1201. Ethanol was used as the liquid 1210. Then, the operation was observed when a voltage of 5 V was applied to the positive wiring electrode 703 and the negative wiring electrode 704 of the heating unit 1204.

[0140] 24(a) shows the state when the switch is open and no voltage is applied to the positive wiring electrode 703 and the negative wiring electrode 704. The surface temperature of the heating unit 1204 is 22.5°C, and the liquid 1210 in the balloon capillary tube 1200 is completely filled.

[0141] FIG. 24(b) shows the state when the switch is closed and a 5 V voltage is applied to the positive wiring electrode 703 and the negative wiring electrode 704. When current flows through the heating unit 1204 for 10 seconds, the temperature of the heating element 701 reaches approximately 80°C, causing the liquid 1210 (ethanol: boiling point 78.37°C) present at the end of the capillary tube 1202 nearby to boil and evaporate, becoming vapor 1211, which expands inside the tube. The vapor pressure of the vapor 1211 then pushes the unvaporized liquid 1210 (ethanol) toward the balloon portion 1201. As a result, the ethanol flows into the deflated balloon portion 1201, and the balloon portion 1201, whose polyolefin coating has become thinner due to the compressed air injection and whose stress has decreased, is forced outward and expands.

[0142] 24(c) shows the state when the switch is opened again and no voltage is applied to the positive wiring electrode 703 and the negative wiring electrode 704. At this time, the temperature of the heating unit 1204 falls below the boiling point, and it was confirmed that the liquid 1210 (ethanol) in the balloon portion 1201 flows back due to the liquefaction of the vapor 1211 and the atmospheric pressure acting on the balloon portion 1201, causing the balloon portion 1201 to deflate again.

[0143] <Actions and Effects> According to the balloon driving unit 1203 of this embodiment, heating is performed near the end of the capillary tube portion 1202 by the heating unit 1204 of the present invention, so that high temperatures are reached locally and instantaneously, which increases the internal pressure in the capillary tube portion 1202 and causes the balloon portion 1201 to expand. This makes it possible to efficiently drive the balloon portion 1201 by expanding and contracting it in a space-saving manner. Furthermore, in this embodiment, instead of directly heating the balloon portion 1201 with a heating element, remote control is possible to heat the vicinity of the end of the capillary portion 1202 on the opposite side of the balloon portion 1201, and therefore, even if the balloon portion 1201 that is actually being driven is touched, burns caused by the heat of the isolated heating element can be prevented. Therefore, this embodiment is suitable for application to driving devices in which a person touches the balloon portion 1201, such as a Braille display device or a fine pressure device.

[0144] <Modification of the Fifth Embodiment> In the balloon capillary 1200 of the fifth embodiment described above, the balloon portion 1201 and the capillary portion 1202 are integrally molded from resin. However, a portion of the capillary portion 1202 can be replaced with a metal tube (hereinafter referred to as a "metal capillary portion") made of heat-resistant metal such as iron, aluminum, or stainless steel, which has good thermal conductivity. FIG. 25 is a longitudinal cross-sectional view of a modified example of the balloon capillary 1200 according to the fifth embodiment. The balloon capillary 1200 of Modification 1 shown in FIG. 25(a) is composed of the balloon portion 1201, a first metal capillary portion 1212, a capillary portion 1202, and a second metal capillary portion 1213. Each component is bonded by a method such as fusion, and the end of the second metal capillary portion 1213 opposite the balloon portion 1201 is covered with resin, which fills the hole and fuses it to seal it. However, the bonding and sealing methods are not limited to these.

[0145] <Manufacturing method> An example of a method for manufacturing the balloon capillary 1200 of the first modified embodiment will be described. A lid-shaped polyolefin resin with an inner diameter of 1.2 mm is placed on the tip of the first SUS tube (first metal capillary tube portion 1212) with an outer diameter of 1.27 mm, and melted with a burner to cap the tip of the first SUS tube.

[0146] Next, while heating the lid-shaped polyolefin resin and the first SUS pipe with a burner, compressed air was blown into the first SUS pipe from the open end, causing the lid-shaped polyolefin resin to expand and form a balloon portion 1201.

[0147] Next, the first SUS tube was cut at a portion 10 mm away from the balloon, and a polyolefin tube (capillary portion 1202) was placed over the cut first SUS tube, and a portion of the polyolefin tube with a length of 500 mm was cut. A burner was then applied to the covered portion, and the tube was fused at the fusion portion 1214.

[0148] Next, a second SUS tube (second metal capillary portion 1213) having a length of 5 mm was inserted into the end of the polyolefin tube that had not yet been fused, and a burner was similarly applied to the inserted portion to fuse it at fused portion 1215. Here, the first and second SUS pipes were connected to both ends of a 500mm polyolefin tube. Since polyolefin tubes shrink due to heat, a burner was applied to the entire polyolefin tube, taking care not to create holes or burnt parts. This caused the tube to shrink from a diameter of 1.2mm to a diameter of 0.6mm, making it more susceptible to capillary action.

[0149] Next, a beaker filled with ethanol was prepared, and the above-mentioned workpiece was immersed in the ethanol. After making sure that the open end of the second SUS pipe was not exposed to the liquid surface, the beaker was placed in a vacuum degassing device, a vacuum of 0.1 MPa was created, and it was confirmed that all the air inside the workpiece in the beaker had been released. Next, the vacuum was returned to atmospheric pressure, and the ethanol was filled inside the workpiece.

[0150] Next, the workpiece filled with ethanol was removed, and with the balloon portion 1201 crushed with a clip, the open end of the second SUS tube was covered with epoxy resin, filled in the hole, and fused to seal it with the sealing portion 1216.

[0151] <Actions and Effects> In the balloon drive unit 1203 using this variant example 1, heating is performed by the second metal capillary portion 1213, which takes advantage of the higher thermal conductivity of metal compared to when heating the capillary portion 1202 made of resin alone, thereby having the effect of speeding up the thermal reactivity of the balloon portion 1201. Furthermore, by interposing the first metal capillary portion 1212 between the balloon portion 1201 and the capillary portion 1202, the formation and size adjustment of the balloon portion 1201 can be easily performed, and manufacturing efficiency is improved.

[0152] The balloon capillary 1200 of Modification 2 shown in Figure 25(b) is composed of a balloon portion 1201, a first metal capillary portion 1212, and a capillary portion 1202, and differs from Modification 1 in that only the first metal capillary portion 1212 has been replaced. The balloon capillary 1200 of Modification 3 shown in Figure 25(c) is composed of a balloon portion 1201, a capillary portion 1202, and a second metal capillary portion 1213, and differs from Modification 1 in that only the second metal capillary portion 1213 has been replaced.

[0153] <Application example of the fifth embodiment> 26 is a schematic diagram of a Braille display device 1300 to which the fifth embodiment is applied. Descriptions of components that are the same as or equivalent to those in the first to fifth embodiments will be simplified or omitted.

[0154] A plurality of U-shaped heating units (12 in FIG. 26) are formed on a single sheet-like substrate 1205. The wiring pattern formed on the substrate is the same as that of the second embodiment except for the number of electrodes. In addition, heat dissipation notches 1206 are formed in the gaps between each U-shaped heating unit. A second metal capillary portion 1213 made of, for example, a SUS tube is fixed on top of each U-shaped heating unit, and the capillary portion 1202 and balloon portion 1201 are connected to this to form a balloon drive unit 1203. However, it goes without saying that the balloon capillary 1200 can have the configuration of this embodiment or other modified examples.

[0155] The balloon portion 1201 of each balloon capillary 1200 is incorporated into a board 1301 with holes, and by touching the holes with one's fingers, the expansion and contraction of the balloon portion 1201 is transmitted to a person as a tactile sensation. The board 1301 incorporating the balloon portion 1201 is separated from the heating element and can be driven by remote control, so there is no risk of getting burned by touching the board. Furthermore, by making the capillary portion 1202 flexible, it is possible to provide flexibility in the arrangement of the substrate 1205 and the board 1301.

[0156] A Braille display device with any number of dots can be formed by stacking multiple substrates 1205 (three in FIG. 26) with a certain gap between them, each substrate having multiple balloon drive units 1203 formed thereon, and incorporating each balloon section 1201 into a predetermined location on board 1301. However, the substrates do not necessarily need to be stacked, and can be arranged as appropriate according to the design.

[0157] <Actions and Effects> The Braille display device of this application example is driven by a heating element that can rapidly heat up a localized area with low power and a balloon capillary, thereby realizing space saving. This also makes it possible to increase the number of Braille dots in a given area, enabling more complex and advanced Braille representation. It goes without saying that such applications are not limited to Braille display devices and can be applied to other fields as well.

[0158] The above describes the embodiments of the present invention, but the present invention is not limited to the above-mentioned embodiments, and various modifications are possible within the scope of the gist of the present invention, such as combining the heating units used in each embodiment.

[0159] For example, it goes without saying that the heating element and driving device can be designed by adjusting the electrode line width, pitch, aspect ratio, etc. of the wiring electrodes without departing from the scope of the present invention.

[0160] Furthermore, the wiring pattern is not limited to a U-shaped wiring pattern or a fan-shaped wiring pattern, and the number of positive electrodes and negative electrodes of the heating unit can be any even or odd number. [Explanation of symbols]

[0161] 200...heating element, 202...positive wiring electrode 203...Negative wiring electrode, 204...Resistor 206, 207...Opposite sides 301... base material, 302... spacing, 303... spacing 500...heating element 502...Positive wiring electrode 503...Negative wiring electrode 506, 507...Opposite sides 602...Metal mesh 603...screen printing plate, 604...syringe, 605...substrate 606...Squeegee 610, 620...screen printing plates, 611...coating agent, 612...mask 613...opening, 614...screen mesh, 615...base material 616: recess, 622: metal mask, 624: metal mesh 701, 702...Flexible sheets 703...positive wiring electrode, 704...negative wiring electrode 705...insulating coating material, 706...notch 801, 802...wiring pattern 803...Negative terminal, 804a, 804b, 804c...Positive terminal 805...Notch, 806...LED flicker, 807...LED chip 808...Butterfly device 1001...Circular wiring pattern 1001a~1001h...Terminals 1001e(X), 1001f(X), 1001g(X)...Connection part 1002ef, 1002fg...resistor 1101...Circular wiring pattern 1101a~1101h...Terminals 1101c(Y), 1101d(Y)...Connection part 1102bc, 1102cd...Resistor 1103...Cut 1200...balloon capillary, 1201...balloon portion, 1202...capillary portion 1203...balloon driving unit, 1204...heat generating unit, 1205...substrate 1206...notch, 1210...liquid, 1211...vapor, 1212...first metal capillary portion 1213...Second metal capillary part, 1214, 1215...Fusion part, 1216...Sealing part 1300...Braille display device, 1301...Board

Claims

1. a substrate; a positive wiring electrode and a negative wiring electrode formed on the substrate and facing each other; and a resistor formed between the facing positive and negative wiring electrodes; the positive and negative wiring electrodes have opposing side surfaces with a slope angle of 70 degrees or more and have a recess on the top surface; The wiring electrodes have an electrode width of 100 to 200 μm, and a pitch that is 1 to 2 times the electrode width. A heating element characterized by:

2. A semiconductor device comprising: a substrate; a positive wiring electrode and a negative wiring electrode formed on the substrate and facing each other; and a resistor formed between the facing positive and negative wiring electrodes; The positive and negative wiring electrodes have opposing side surfaces with a slope angle of 70 degrees or more and have recesses on their upper surfaces that are the marks of a screen mesh. A heating element characterized by:

3. 3. The heating element according to claim 2, wherein the wiring electrodes have an electrode width of 100 to 200 μm and a pitch that is 1 to 2 times the electrode width.

4. 4. The heating element according to claim 1, wherein the wiring electrodes have an aspect ratio of 0.5 to 4.

5. The heating element according to any one of claims 1 to 4, wherein the width of the recess is 10 to 40 µm.

6. the substrate is a flexible sheet formed by laminating two or more sheets having different linear expansion coefficients, A driving device using the heating element according to any one of claims 1 to 5, wherein the heating unit has a notch around its periphery.

7. 7. The drive device according to claim 6, wherein the wiring patterns of the positive and negative wiring electrodes are U-shaped wiring patterns.

8. Multiple U-shaped heating units are arranged in a circle, The driving terminals of the first polarity are connected to the wiring electrodes in the U-shaped wiring patterns of the U-shaped heating units arranged clockwise and counterclockwise, which are adjacent to each other; a drive terminal of a second polarity having a different polarity is adjacent to the drive terminal of the first polarity; the second polarity driving terminals are connected to wiring electrodes in the U-shaped wiring patterns of the U-shaped heating units arranged clockwise and counterclockwise adjacent to each other; the clockwise wiring electrode connected to the drive terminal of the first polarity and the counterclockwise wiring electrode connected to the drive terminal of the second polarity constitute wiring electrodes facing each other in the same U-shaped wiring pattern; 8. The drive device according to claim 7, wherein the drive device comprises:

9. the wiring patterns of the positive wiring electrode and the negative wiring electrode are fan-shaped wiring patterns, Multiple fan-shaped heating units are arranged in a circle, The driving terminals of the first polarity are connected to the wiring electrodes of the fan-shaped wiring patterns of the fan-shaped heating units arranged clockwise and counterclockwise and adjacent to each other; a drive terminal of a second polarity having a different polarity is adjacent to the drive terminal of the first polarity; the driving terminals of the second polarity are connected to wiring electrodes in the fan-shaped wiring patterns of the fan-shaped heating units arranged clockwise and counterclockwise adjacent to each other; the clockwise wiring electrode connected to the drive terminal of the first polarity and the counterclockwise wiring electrode connected to the drive terminal of the second polarity constitute wiring electrodes facing each other in the same fan-shaped wiring pattern; 7. The drive device according to claim 6, wherein the drive device comprises:

10. a balloon capillary tube having a balloon portion and a capillary portion, the end of the capillary portion opposite to the balloon portion being closed and sealed, and filled with a low-boiling point solvent; The driving device using a heating element according to any one of claims 1 to 5, wherein the balloon capillary is fixed so that the end of the capillary portion opposite the balloon portion is in close contact with a heating unit.

11. The drive unit according to claim 10 , wherein at least a portion of the end of the capillary tube on the balloon side or a portion of the end opposite the balloon side is made of a metal capillary tube.

12. 12. The driving device according to claim 10, wherein the base material is arranged in a plurality of sheets, each of which has a plurality of balloon driving units each of which is formed by combining the heating unit with the balloon capillary tube fixed to the heating unit.

Images