JP6673855B2 - Liquid detection sensor - Google Patents

Description

The present invention relates to a liquid detection sensor for detecting the liquid.

  There are Patent Documents 1 and 2 as liquid detection sensors capable of detecting liquid. Patent Literature 1 includes a water-permeable cloth sheet sandwiched between a porous metal sheet and a non-porous metal sheet, and an aqueous sheet disposed on the porous metal sheet on the opposite side of the non-porous metal sheet. Are integrated with each other by fixing the end portions with a known fixing method such as an adhesive or an adhesive tape.

  Patent Document 2 has a base extending in the longitudinal direction from the terminal portion, at least a pair of comb-shaped electrodes consisting of a plurality of teeth substantially perpendicular to the base, and a hydrophilic non-woven fabric stuck on the comb-shaped electrode, A configuration is disclosed in which a base (teeth) of a pair of comb-shaped electrodes and a tooth are opposed to each other with an appropriate gap therebetween to easily adjust the length (the number of teeth) according to a space.

Japanese Patent No. 4349360 JP-A-2003-222602

  However, the above-described conventional configuration has a problem that the handleability during construction is insufficient. Specifically, in Patent Literature 1, since the ends of each sheet are integrated by fixing with an adhesive or an adhesive tape or the like, when the size or shape of the installation target is different, it is adapted to the installation target. After cutting into each size and shape as described above, it is necessary to fix the end of each sheet. Further, in Patent Literature 2, the length in the longitudinal direction (one-dimensional direction) can be changed from the terminal portion by adjusting the number of teeth, but the size and shape in the plane direction (two-dimensional direction) are changed. It is not possible to respond sufficiently to different installation targets. Further, in the configurations of Patent Documents 1 and 2, when attaching to the installation target, an operation of fixing to the installation target with an adhesive or an adhesive tape is required.

The present invention has been made in consideration of the above problems, and an object thereof is to provide a readily liquid detection sensor that can be installed on the installation target with cleavable into any shape and size in a plane direction .

The invention of the present application is a liquid detection sensor, wherein a first electrode layer having conductivity and liquid permeability is disposed to face the entire surface of the first electrode layer, and the presence of a liquid that has passed through the first electrode layer an insulating layer that exhibits conductivity, the oppositely arranged through the insulating layer on the entire surface of the first electrode layer, have a second electrode layer having conductivity and tackiness, the second electrode layer The surface opposite to the insulating layer side is a surface that is in contact with the installation target, and has conductivity and adhesiveness.

  According to the above configuration, the liquid detection sensor has a laminated structure of the first electrode layer, the insulating layer, and the second electrode layer on the entire surface. Since it has a liquid detecting ability and an adhering ability at an arbitrary portion (in the dimensional direction), it can be cut into an arbitrary shape and size in the plane direction and can be easily attached to an installation target.

  The first electrode layer in the present invention may have a first electrode conductive layer in which a plurality of openings through which the liquid permeates are formed of a conductive paint.

  According to the above configuration, since the size and shape of the opening can be easily changed by the conductive paint having a high degree of freedom in processing such as coating and printing, the liquid permeability of the first electrode layer can be easily changed. Can be easily adjusted according to the application.

  In the first electrode conductive layer according to the present invention, the opening may be formed by crossing linear portions made of the conductive paint.

  According to the above configuration, the amount of the conductive paint used can be suppressed as compared with the case where the conductive paint is formed on the entire surface, and a continuous connection relationship is obtained by the intersection of the plurality of linear portions. Thereby, conductivity can be exhibited also in the plane direction of the first electrode conductive layer.

  In the present invention, the first electrode layer is provided between the first electrode conductive layer and the insulating layer, and has a plurality of openings for transmitting the liquid that has passed through the first electrode conductive layer. It may have a layer.

  According to the above configuration, the conductive adhesive sheet can be adhered to the insulating layer after the first electrode conductive layer is formed by printing or applying the conductive paint to the partial adhesive layer. Obtainable.

  The second electrode layer according to the present invention has one surface joined to the insulating layer, and has a conductive second electrode conductive layer, and is joined to the other surface of the second electrode conductive layer, and is electrically conductive at least in a thickness direction. And a conductive adhesive layer having adhesiveness.

  According to the above configuration, the second electrode layer having adhesiveness and conductivity can be easily formed.

  In the present invention, the second electrode conductive layer has one surface bonded to the insulating layer, a conductive adhesive layer having conductivity at least in a thickness direction, and one surface bonded to the other surface of the conductive adhesive layer, And a second electrode conductive sheet having conductivity.

  According to the above configuration, after the second electrode conductive sheet is formed between the conductive adhesive layer and the conductive adhesive layer into a double-sided tape shape and then bonded to the insulating layer, the liquid detection sensor can be easily manufactured. Can be formed.

  The second electrode layer in the present invention has a second electrode conductive sheet in which a plurality of concave portions are dispersedly arranged on the entire surface opposite to the insulating layer side, and an adhesive accommodated in the concave portions. Is also good.

  According to the above configuration, the pressure-sensitive adhesive contained in the concave portion exhibits adhesiveness, and a portion other than the concave portion in the second electrode conductive sheet exhibits electrical conductivity, whereby the second electrode having adhesiveness and electrical conductivity is provided. The electrode layer can be easily formed. Further, since a portion other than the concave portion becomes an exposed portion of the second electrode conductive sheet, an inexpensive material can be used for the adhesive.

  The second electrode layer according to the present invention has a plurality of recesses distributed over the entire surface on the insulating layer side and a plurality of recesses distributed over the entire surface on the side opposite to the insulating layer. A conductive sheet, an adhesive accommodated in the concave portion disposed on the insulating layer side of the second electrode conductive sheet, and the concave portion disposed on a side of the second electrode conductive sheet opposite to the insulating layer side And a pressure-sensitive adhesive stored therein.

  According to the above configuration, the adhesive layer is formed on the surface of the second electrode conductive sheet on the insulating layer side, and the adhesive layer is formed on the surface opposite to the insulating layer side by forming the adhesive layer. The second electrode layer bonded to the substrate can be easily formed. Further, since a portion other than the concave portion becomes an exposed portion of the second electrode conductive sheet, an inexpensive material can be used for the adhesive.

  The second electrode conductive sheet according to the present invention may include a mesh structure of a metal-plated fiber, and an adhesive buried in an opening of the mesh structure.

  According to the above configuration, the second electrode conductive sheet can be easily formed.

  In the present invention, the second electrode layer has one surface joined to the insulating layer, and has a conductive second electrode conductive layer, and is dispersed and disposed on the entire other surface of the second electrode conductive layer, and has an adhesive. May be provided with a plurality of adhesive portions formed by.

  According to the above configuration, by using the electrode clip having the connector portion made of the material that passes through the gap between the adjacent adhesive portions and comes into contact with the second electrode conductive layer, it is possible to use the non-conductive adhesive. Since it becomes possible, the cost of the liquid detection sensor can be reduced.

  It can be cut into any shape and size in the plane direction and can be easily attached to the installation target.

It is a perspective view of a liquid detection sensor. FIG. 9 is an explanatory diagram illustrating a method of using the liquid detection sensor. It is a perspective view of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. FIG. 3 is a perspective view of a first electrode conductive layer. It is explanatory drawing of the AA arrow line end surface of the liquid detection sensor in FIG. 5A. It is a perspective view of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. FIG. 3 is an explanatory diagram illustrating an outline of a liquid detection sensor. It is explanatory drawing which shows the use condition of an electrode clip.

  Hereinafter, preferred embodiments of the present invention will be described with reference to the drawings.

(Liquid detection sensor: overview)
As shown in FIG. 1, a liquid detection sensor 1 includes a first electrode layer 2 having conductivity and liquid permeability and a liquid that is disposed to face the entire surface of the first electrode layer 2 and that has passed through the first electrode layer 2. Has an insulating layer 3 exhibiting conductivity due to the presence of the first electrode layer 2 and a second electrode layer 4 having conductivity and adhesiveness, which is disposed to face the entire surface of the first electrode layer 2 with the insulating layer 3 interposed therebetween. .

  Here, the “conductivity” means a property that conducts electricity in the plane direction and the thickness direction in a region equal to or more than a cutting unit in the plane direction (two-dimensional direction in the vertical direction and the horizontal direction) of the liquid detection sensor 1 The resistance value may be uniform at all points in the direction, or may be non-uniform at at least a part of the surface direction. That is, as long as the first electrode layer 2 and the second electrode layer 4 have conductivity that can detect the insulation state and the conduction state of the insulating layer 3 between the first electrode layer 2 and the second electrode layer 4. Good.

  The “cutting unit” is the minimum unit that can be cut into an arbitrary shape and size when the liquid detection sensor 1 is viewed from the thickness direction. The liquid detection sensor 1 can cut out an arbitrary shape such as a circular shape, an elliptical shape, a ring shape, and a polygonal shape in various sizes by including the “cut unit”, and further cuts out the cut out liquid detection sensor 1. It can be subdivided into any shape and size. Thus, for example, immediately after manufacturing, a long liquid detection sensor 1 is created, transported and stored in a large roll state, and when transported from a storage location to a detection target at the site, the worker carries or transports the liquid. A liquid detection sensor for carrying and transporting, which is cut out into a shape and size suitable for transporting a vehicle, and when mounted on a detection target, a liquid detection sensor for installation cut out into a shape and size suitable for the mounting location of the installation target 1 can be processed.

  “Liquid-permeable” means a property that allows liquid to pass through at least in the thickness direction in a region equal to or more than the cutting unit in the surface direction of the liquid detection sensor 1. “Liquid permeability” may be uniform at all portions in the surface direction, or may be non-uniform at at least a portion of the surface direction. In applications where the time from the start of liquid leakage to the detection of liquid leakage is important, it is preferable that the liquid has uniform liquid leakage at all locations in the surface direction.

  In the “facing arrangement”, the surfaces of the first electrode layer 2, the insulating layer 3, and the second electrode layer 4 do not need to be completely parallel. “Liquid” is a liquid detection target by the liquid detection sensor 1 and is not limited to a material or physical properties as long as it is liquid. The liquid means that the insulating layer 3 has fluidity enough to be impregnated and stored. The type of the “liquid” may be an organic substance such as an acid, an alkali, an oil, and an organic solvent, in addition to a body fluid, a drug solution, and water containing impurities. Further, the physical properties of the “liquid” may be any substance that is liquefied at the environmental temperature at which the liquid detection sensor 1 is used.

  The “adhesiveness” of the second electrode layer 4 only needs to have a property of adhering to the installation target in a region equal to or more than the cutting unit in the surface direction of the liquid detection sensor 1. Note that the adhesive means having adhesiveness at least within the environmental temperature range of the installation target, and is not necessarily limited to a state of exhibiting adhesiveness at room temperature of about 20 degrees Celsius. For example, in the case where the environmental temperature range of the installation target is around 100 degrees Celsius, even if it loses adhesiveness at room temperature, if it has adhesiveness around 100 degrees Celsius, it corresponds to the "adhesion" of the second electrode layer 4 I do. Examples of the adhesive exhibiting "adhesiveness" at room temperature include acrylic resins, rubber resins, silicone resins, urethane resins, and elastomer resins.

  The "adhesiveness" is only required to realize a state in which the liquid detection sensor 1 is detachably attached to an installation target, and does not necessarily mean a state in which the liquid detection sensor 1 is attached by an adhesive. For example, when the installation target has magnetism, the second electrode layer 4 may have a magnetic force in the thickness direction, and may be attached to the installation target by the magnetic force. Further, any one or more of the first electrode layer 2, the insulating layer 3, and the second electrode layer 4 may have a magnetic force in the thickness direction. “Tackiness” may be realized by static electricity of the second electrode layer 4. In this case, since the adhesiveness is exhibited to various materials, the types and materials of the installation target can be expanded. Further, “adhesiveness” may be realized by a combination of one or more of the above-described adhesive, magnetic force, and static electricity. In this case, for example, after being temporarily fixed by magnetic force or static electricity, after alignment, the liquid detection sensor 1 can be strongly pressed against the installation target and adhered with an adhesive for a long period of time.

  According to the above configuration, the liquid detection sensor 1 is a liquid detection sensor 1 having a laminated structure of the first electrode layer 2, the insulating layer 3, and the second electrode layer 4 on the entire surface. An arbitrary portion in the plane direction has a liquid detecting ability and a sticking ability. Thereby, the liquid detection sensor 1 can be cut into an arbitrary shape and size in the plane direction and can be easily attached to the installation target. For example, as shown in FIG. 2, by cutting the large-sized liquid detection sensor 1 in the direction of the arrow shown by the solid line in the drawing, a long thin band-shaped liquid detection sensor 1 is formed. 1 can be attached along the longitudinal direction of the optical fiber cable 6 to be installed. Thereafter, the installation work can be completed by sandwiching both surfaces (the first electrode layer 2 and the second electrode layer 4) at one end of the liquid detection sensor 1 with the electrode clips 5.

  In addition, in the liquid detection sensor 1, a release sheet having the same shape as the outer shape may be provided on the upper surface (the exposed surface of the first electrode layer 2) and the lower surface (the exposed surface of the second electrode layer 4). The release sheet enables the adhesiveness of the second electrode layer 4 to be maintained for a long period of time, and also allows the adhesiveness of the liquid detection sensor 1 to the installation target only when necessary. Further, the liquid detection sensor 1 configured as described above may have a perforation for cutting in a vertical direction, a horizontal direction, or an oblique direction, so that the liquid detection sensor 1 can be easily cut manually.

(Liquid detection sensor: 1st electrode layer)
As shown in FIG. 1, the first electrode layer 2 has a first electrode conductive layer 21 in which a plurality of openings 21a through which a liquid is transmitted are formed of a conductive paint. Accordingly, the liquid detection sensor 1 can easily change the size and shape of the opening 21a by using a conductive paint having a high degree of freedom in processing such as coating and printing. Can be easily adjusted according to the application.

  The conductive paint becomes a thin film when spread on the surface of the object in a fluidized state, and as a solid film remains adhered to the surface of the object over time, continuously covers the surface and exhibits conductivity. Examples thereof include liquid conductive ink and paste-like conductive paste.

  Examples of the conductive paste include a silver paste, a silver-coated copper paste, and a carbon paste.

  The first electrode conductive layer 21 formed of a conductive paint will be specifically described. In the first electrode conductive layer 21, an opening 21a is formed by crossing a linear portion 211 made of a conductive paint. . That is, the opening 21a is formed by being surrounded by three or more intersecting linear portions 211 so as to have a polygonal shape having three or more intersections (vertices) at which the linear portions 211 intersect. I have. As a result, the first electrode conductive layer 21 has a smaller amount of conductive paint than the case where the first electrode conductive layer 21 is formed in a sheet shape using conductive paint, and the plurality of linear portions 211 intersect. By being in a continuous connection relationship, it has conductivity in the thickness direction and the plane direction, similarly to the case where the conductive paint is used to form a sheet.

  The linear portion 211 may be a straight line or a curved line, or a combination thereof. The linear portion 211 preferably has a width smaller than the maximum diameter or the average diameter of the opening 21a. Further, it is preferable that the linear portion 211 has a thickness (height) smaller than the maximum diameter or the average diameter of the opening 21a. Thereby, the first electrode conductive layer 21 can easily obtain good liquid permeability due to a large opening area.

  Further, the linear portions 211 may be arranged parallel to the vertical and horizontal directions of the first electrode conductive layer 21, or may be arranged to be inclined. The thickness (height) and line width of one intersecting linear portion 211 and the other linear portion 211 may be the same or different. If the thickness (height) of one of the linear portions 211 is reduced or the line width is reduced, the amount of the conductive paint used can be further reduced. For example, for one linear portion 211 that contacts the connector portion of the electrode clip 5, the line width is increased, and the thickness (height) is set to a predetermined value suitable for the contact. By reducing the line width and the thickness (height), it is possible to reduce the amount of conductive paint used.

(Liquid detection sensor: first electrode layer: partial adhesive layer)
The first electrode layer 2 has a partial adhesive layer 22 which is disposed between the first electrode conductive layer 21 and the insulating layer 3 and has a plurality of openings through which the liquid that has passed through the first electrode conductive layer 21 passes. doing. The lower limit of the ratio (opening ratio) between the bonded portion and the non-bonded portion in the partial bonding layer 22 is 1: 9, preferably 2: 8, and more preferably 4: 6. The upper limit of the ratio (opening ratio) between the bonded portion and the non-bonded portion is 9: 1, preferably 8: 2, and more preferably 6: 4.

As the partial adhesive layer 22, a liquid-permeable sheet-like adhesive layer having a porous structure can be used. Examples of the adhesive constituting the sheet-like adhesive layer include polyurethane, polyester, polyamide, polyolefin, and EVA. Further, as the partial adhesive layer 22, a molded product obtained by molding a hot melt resin into a woven fabric, a nonwoven fabric, a knitted fabric, a net shape, a lattice shape, or the like can be used. The hot melt resin contains a thermoplastic resin as a main component, and has a melting point of preferably 200 ° C. or lower, more preferably 150 ° C. or lower. Also, the basis weight is preferably from 100 g / m ² or less, 50 g / m ² or less is more preferable.

  As a result, the liquid detection sensor 1 performs a process of forming the first electrode conductive layer 21 having the linear portions 211 and the like by printing or applying a conductive paint on the partial adhesive layer 22 and a process of forming the first electrode conductive layer 21. By performing a process of laminating the partial adhesive layer 22 with the adhesive layer on the insulating layer 3 and a process of heating and pressing in the laminating direction while maintaining the laminated state, the partial adhesive layer 22 is fused to the insulating layer 3. The first electrode layer 2 can be bonded to the insulating layer 3 so as to be liquid-permeable.

  The partial adhesive layer 22 may have conductivity, or may not have conductivity. In the case where there is no conductivity, the liquid can be detected when the liquid exists in the opening of the partial adhesive layer 22 and the insulating layer 3. On the other hand, if the insulating layer 3 has conductivity, the liquid can be detected as long as the liquid exists in the insulating layer 3 even if the liquid does not exist in the opening of the partial adhesive layer 22. That is, when the insulating layer 3 has conductivity, even if the liquid is dried from the surface side where the liquid has entered the liquid detection sensor 1 as long as the liquid exists in the insulating layer 3, it is possible to detect a slight leak. The liquid can be continuously detected.

(Liquid detection sensor: first electrode layer: modified example)
In the above liquid detection sensor 1, the case where the first electrode layer 2 includes the first electrode conductive layer 21 formed by the linear portion 211 has been described, but the present invention is not limited to this. For example, as shown in FIG. 3, the first electrode conductive layer 21 may be formed by a metal sheet having openings 21a, metal plating, or metal coating.

  As shown in FIG. 4, the first electrode conductive layer 21 is a conductive sheet 212 having an opening 212a and a penetrating filling hole 212b, and the filling hole 212b is filled with a thermoplastic adhesive 23. You may. In this case, by heating and pressing in the thickness direction in a state where the conductive sheet 212 and the insulating layer 3 are in contact with each other, the thermoplastic adhesive 23 is fused to the insulating layer 3, thereby forming the first electrode conductive layer. The layer 21 (conductive sheet 212) and the insulating layer 3 can be directly bonded. As a result, the liquid detection sensor 1 in which the number of the partial adhesive layers 22 is reduced can be obtained.

  The conductive sheet 212 may be made of any material as long as it has conductivity. As a material for forming the conductive sheet 212, any of nickel, copper, silver, tin, gold, palladium, aluminum, chromium, titanium, carbon, and zinc, or an alloy containing two or more of these can be used. . Among them, metals such as aluminum and copper are preferable.

  Further, as shown in FIG. 5A, the first electrode conductive layer 21 has a cross-sectional end surface shape of two line segments (AA line, BB line, or the like) intersecting in a plane direction, a waveform shape or an uneven shape. A plurality of openings 213a may be formed in the conductive sheet 213, and the thermoplastic adhesive 23 may be accommodated in the concave portion on the insulating layer 3 side. In this case, for example, as shown in 5B showing the end face shape of the AA line, when the conductive sheet 213 is brought into contact with the insulating layer 3 and then pressed and heated, the thermoplastic adhesive 23 is melted, The thermoplastic adhesive 23 contained in the concave portion 213b of the conductive sheet 213 comes into contact with the insulating layer 3 because at least the top of the convex portion 213c is elastically deformed while being in contact with the insulating layer 3. Then, by ending the heating while maintaining the pressurized state, the state where the conductive sheet 213 is in contact with the insulating layer 3 is maintained when the thermoplastic adhesive 23 is solidified and fixed to the insulating layer 3. As a result, similarly to the first electrode conductive layer 21 of FIG. 4, the liquid detection sensor 1 in which the partial adhesive layer 22 is reduced can be obtained. In addition, by adjusting the depth (height) of the unevenness, the filling amount of the thermoplastic adhesive 23 can be adjusted, so that the adhesive strength can be adjusted. Further, since the conductive sheet 213 is in contact with the insulating layer 3, any of the conductive and non-conductive thermoplastic adhesives 23 can be used.

  In addition, the conductive sheet 213 may be formed such that an end surface shape of a cross section at an arbitrary line segment in a plane direction is a corrugated shape or an uneven shape. Further, in the conductive sheet 213, instead of the thermoplastic adhesive 23, an adhesive which solidifies at normal temperature may be accommodated in the recess 213b.

(Liquid detection sensor: insulating layer)
The insulating layer 3 exhibits conductivity due to the presence of the liquid. That is, the insulating layer 3 is in an insulating state with a high resistance value when the liquid is not impregnated or the like, and is in a conductive state with a small resistance value when a liquid is present. Therefore, when the insulating layer 3 is not impregnated with a liquid or the like, there is no electrical connection between the first electrode layer 2 and the second electrode layer 4 due to the insulating layer 3.

  The insulating layer 3 has a structure that exhibits conductivity due to the presence of a liquid and absorbs and holds the liquid. That is, the insulating layer 3 is configured to change from insulative to conductive as a whole due to permeation of the liquid.

  The “liquid-absorbing / holding structure” provided in the insulating layer 3 is not limited to a material and a shape as long as the structure is such that the liquid to be detected penetrates. Examples thereof include a nonwoven fabric structure, a porous structure having open cells, a structure in which one or more holes are formed in a nonporous material, and a structure in which one or more slits are formed in a nonporous material. When the insulating layer 3 is a nonwoven fabric or paper, even a small amount of liquid permeates the insulating layer 3 by capillary action and changes from an insulating state to a conductive state. It can be.

  The material of the insulating layer 3 is not particularly limited as long as it has a high resistance value when not in contact with the liquid. For example, a nonwoven fabric, a gauze, a bandage, a bandage, a paper tape, or the like can be used for the insulating layer 3.

  Specifically, the material of the insulating layer 3 includes plant fibers (cellulose fibers) such as cloth (cotton, hemp, etc.) and paper, chemical fibers (rayon, cupra, etc.), ceramics, engineering plastics, porous materials (sponges, etc.). ) Is exemplified. Examples of engineering plastics include polypropylene, cross-linked polyethylene, polyester, polybenzimidazole, aramid, polyimide, polyimide amide, polyetherimide, polyphenylene sulfide (PPS), polyethylene naphthalate (PEN), polyethylene terephthalate (PET), and the like.

More specifically, a nonwoven fabric made of a polyester resin manufactured by Unitika Ltd. (registered trademark: MARIX) can be used for the insulating layer 3. This nonwoven fabric has hydrophilicity because the resin that bonds the polyester fibers is a water-soluble acrylic resin. The method for producing the nonwoven fabric is a spunbond method. When the nonwoven fabric part number is # 20507WTD, the basis weight is 50 g / m ² and the average thickness is 155 μm. When the nonwoven fabric product number is # 20604FLD, the basis weight is 60 g / m ² and the average thickness is 150 μm. When the nonwoven fabric part number is # 10606WTD, the basis weight is 60 g / m ² and the average thickness is 215 μm (having bulkiness).

  The thickness of the insulating layer 3 is preferably from 10 to 3000 μm. Further, it is preferable that the insulating layer 3 has lyophilicity for a liquid to be detected. For example, if the liquid to be detected is water, it is preferably hydrophilic. With the lyophilic structure, even a small amount of liquid permeates into the insulating layer 3 and changes from an insulating state to a conductive state. Therefore, it is possible to detect even a small amount of liquid and shorten the time until the detection.

  The insulating layer 3 may be a material having lyophilic property itself or a lyophobic material having a lyophilic layer formed on a surface thereof. For example, the insulating layer 3 may have a surfactant having a surface activity with respect to the liquid attached to at least a part of a contact portion with the liquid in the liquid absorbing / holding structure. In this case, the sheet member 1 that can select the detection target such as water or oil can be used by properly using the type of the surfactant according to the type of the liquid to be detected.

  Further, the insulating layer 3 may have a dissolving material (inorganic salts: sodium chloride, sodium sulfate, calcium chloride, magnesium hydroxide, etc.) that dissolves in a liquid and ionizes. In this case, even if the liquid itself has no conductivity (pure water, oil, or the like), the dissolved material ionized by the liquid can change the insulating layer 3 to be conductive.

(Liquid detection sensor: second electrode layer: second electrode conductive layer)
As shown in FIG. 6, the second electrode layer 4 has one surface bonded to the insulating layer 3 and a conductive second electrode conductive layer 41, and the other surface of the second electrode conductive layer 41 bonded to the other surface. It has a conductive adhesive layer 42 having conductivity at least in the thickness direction and having tackiness.

  The second electrode conductive layer 41 is, for example, a metal sheet or a metal foil, or a coating layer of an isotropic conductive adhesive or a conductive paint that solidifies at room temperature. Examples of the conductive adhesive layer 42 include an isotropic conductive adhesive and an anisotropic conductive adhesive having adhesiveness at room temperature.

  As shown in FIG. 1, the second electrode conductive layer 41 has one surface adhered to the insulating layer 3 and has at least a conductive adhesive layer 411 having conductivity in the thickness direction. And a second electrode conductive sheet 412 which is adhered to the surface and has conductivity. According to this configuration, after the second electrode conductive sheet 412 is formed into a double-sided tape shape with the conductive adhesive layer 411 and the conductive adhesive layer 42 interposed therebetween, it can be joined to the insulating layer 3. 1 can be easily formed.

  The conductive adhesive layer 411 includes a resin and conductive particles. Examples of the resin material include an acrylic resin, a silicone resin, a thermoplastic elastomer resin, a rubber resin, and a polyester resin. Specific examples include KP-1581, KP-1104, KP-2074, and SZ-6153 manufactured by Nippon Carbide, and AR-2172-M3 manufactured by Big Technos. Some or all of the conductive particles are formed of a metal material.

  Examples of the material of the conductive particles include copper powder, silver powder, nickel powder, silver-coated copper powder (Ag-coated Cu powder), gold-coated copper powder, silver-coated nickel powder (Ag-coated Ni powder), and gold-coated nickel. There are powders and carbon powders, and these metal powders can be produced by a water atomizing method, a carbonyl method, or the like. In addition to the above, particles obtained by coating a metal powder with a resin and particles obtained by coating a resin with a metal powder can also be used. The conductive particles are preferably Ag-coated Cu powder or Ag-coated Ni powder. The reason for this is that conductive particles with improved conductivity can be obtained with inexpensive materials.

  The second electrode conductive sheet 412 may be made of any material as long as it has conductivity, similarly to the above-described conductive sheet 212. As a material for forming the conductive sheet 212, any of nickel, copper, silver, tin, gold, palladium, aluminum, chromium, titanium, carbon, and zinc, or an alloy containing two or more of these is used. it can. Among them, metals such as aluminum and copper are preferable.

(Liquid detection sensor: second electrode layer: modified example)
In the above description, the second electrode layer 4 has a configuration in which the first electrode layer 2 has the second electrode conductive layer 41 and the conductive adhesive layer 42, but is not limited thereto. . Specifically, as shown in FIG. 7, the second electrode layer 4 includes a flat plate-like second electrode conductive sheet 413 in which a plurality of recesses 413a are dispersedly arranged on the entire surface opposite to the insulating layer 3 side. A configuration including the adhesive 43 accommodated in the concave portion 413a may be employed. According to this configuration, the adhesive 43 accommodated in the concave portion 413a exhibits adhesiveness, and a portion of the second electrode conductive sheet 413 other than the concave portion 413a exhibits electrical conductivity. The formed second electrode conductive layer 41 (second electrode layer 4) can be easily formed. Further, since a portion other than the concave portion 413a becomes an exposed portion of the second electrode conductive sheet 413, an inexpensive material can be used for the adhesive 43.

  Further, in the second electrode conductive sheet 413, a plurality of concave portions 413a are respectively dispersedly arranged on the entire surface on the insulating layer 3 side and on the entire surface opposite to the insulating layer side, and the adhesive 43 is accommodated in these concave portions 413a. You may. That is, the second electrode layer 4 has a plurality of concave portions 413a distributed over the entire surface on the insulating layer 3 side and a plurality of concave portions 413a distributed over the entire surface on the side opposite to the insulating layer 3 side. The electrode conductive sheet 413, the adhesive 43 accommodated in the concave portion 413a disposed on the insulating layer 3 side of the second electrode conductive sheet 413, and the adhesive 43 disposed on the side opposite to the insulating layer 3 side of the second electrode conductive sheet 413. And the pressure-sensitive adhesive 43 accommodated in the recessed portion 413a.

  According to the above configuration, the second electrode conductive sheet 413 in the form of a double-sided tape in which the adhesive 43 is disposed on the surface on the insulating layer 3 side and the surface on the side opposite to the insulating layer side can be used. The second electrode conductive layer 41 (the second electrode layer 4) joined to the first electrode layer can be easily formed, and the conductive adhesive layer 411 can be reduced. In addition, a portion other than the concave portion 413a becomes an exposed portion (electric contact portion) of the second electrode conductive sheet, and the adhesive 43 does not need to be conductive. Therefore, an inexpensive material can be used for the adhesive 43.

  As shown in FIG. 8, the second electrode conductive sheet 416 may be formed such that the end face shape of the cross section at two line segments intersecting in the plane direction is corrugated or uneven. In this case, it is possible to easily form a plurality of recesses 416a that are substantially uniformly distributed. According to this configuration, when the second electrode conductive sheet 416 abuts on the installation target, the adhesive 43 contained in the concave portion 416a on the opposite side to the insulating layer 3 side adheres to the installation target, and at least the convex portion 416b The top portion comes into contact with the connector portion of the electrode clip 5.

  Further, as shown in FIG. 9, the corrugated or uneven second electrode conductive sheet 416 accommodates the adhesive 43 in the concave portion 416c on the insulating layer 3 side and the concave portion 416a on the opposite side to the insulating layer 3 side. It may be. In this case, the second electrode conductive sheet 416 can be directly joined to the insulating layer 3 and the conductive adhesive layer 411 can be reduced. The second electrode conductive sheet 416 in FIGS. 8 and 9 may be formed such that the end face shape of the cross section at an arbitrary line segment in the plane direction is a corrugated shape or an uneven shape.

  As shown in FIG. 10, the second electrode conductive sheet 414 may have a configuration in which a plurality of through holes 414 a are dispersedly arranged on the entire surface, and the through holes 414 a are filled with the adhesive 43. According to this configuration, the double-sided tape-shaped second electrode conductive sheet 414 in which the adhesive 43 is disposed on both sides can be easily formed.

  As shown in FIG. 11, the second electrode conductive sheet 414 has a structure including a metal-plated fiber mesh structure 415 and an adhesive 43 buried in the opening 415 a of the mesh structure 415. It may be. According to the above configuration, since the opening 415a does not need to be formed, the second electrode conductive sheet 414 can be easily obtained.

  As shown in FIG. 12, the second electrode layer 4 has one surface joined to the insulating layer 3 and has conductivity, and the other surface of the second electrode conductive layer 41 has the entirety. And a plurality of adhesive portions 421 formed of an adhesive. According to the above configuration, by using the electrode clip 5 having the connector portion made of the material that passes through the gap between the adjacent adhesive portions 421 and comes into contact with the second electrode conductive sheet 412, the adhesive having no conductivity can be removed. Since the liquid detection sensor 1 can be used, the cost of the liquid detection sensor 1 can be reduced.

(Electrode clip)
As shown in FIG. 12, the electrode clip 5 is used by sandwiching the liquid detection sensor 1 between the connector portions 51 and 52. The connector portion 51 has a rigidity and a thickness to be brought into contact with the second electrode conductive sheet 412 (the second electrode conductive layer 41) through the gap between the adjacent adhesive portions 421 by the pressure when the liquid detection sensor 1 is sandwiched. Have.

  More specifically, the electrode clip 5 has a movable holding portion 514 and a fixed holding portion 515 that can hold the liquid detection sensor 1 in the thickness direction. It is preferable that the movable holding portion 514 and the fixed holding portion 515 are made of a material such as a synthetic resin or ceramics having dimensional stability and electrical insulation. The connector section 52 is provided on the movable holding section 514 so as to be in contact with the first electrode conductive layer 21. On the other hand, the connector portion 51 is provided on the fixed holding portion 515 so as to be in contact with the second electrode conductive sheet 412.

  The connectors 51 and 52 may be made of any material as long as it has conductivity. As a material for forming the connector-side electrode members 211a and 211b, any one of nickel, copper, silver, tin, gold, palladium, aluminum, chromium, titanium, carbon, and zinc, or an alloy containing two or more of these materials Etc. can be used. Among them, metals such as aluminum and copper are preferable.

  The connector portion 51 is set to have such a rigidity and a thickness that the connector portion 51 comes into contact with the second electrode conductive sheet 412 from the gap between the adjacent adhesive portions 421 by the pressure when the liquid detection sensor 1 is sandwiched. For example, the connector portion 51 is formed of a structure made of a nonwoven fabric of a conductive material such as a metal or a structure in which a plurality of conductive sheets are laminated so as to be deformable in a thickness direction.

  In the above detailed description, characteristic portions have been mainly described so that the present invention can be more easily understood. However, the present invention is not limited to the embodiment described in the above detailed description, and other embodiments may be implemented. It can also be applied to forms, and its scope should be interpreted as broadly as possible.

  Further, the terms and wording used in the present specification are used for accurately describing the present invention, and are not used for limiting the interpretation of the present invention. In addition, those skilled in the art will easily be able to infer other configurations, systems, methods, and the like included in the concept of the present invention from the concept of the invention described in this specification. Therefore, the description of the claims should be regarded as including equivalent configurations without departing from the technical idea of the present invention. In addition, in order to fully understand the purpose of the present invention and the effects of the present invention, it is desired that the already disclosed documents and the like be sufficiently considered.

DESCRIPTION OF SYMBOLS 1 Liquid detection sensor 2 1st electrode layer 21 1st electrode conductive layer 21a Opening 21b Filling hole 211 Linear part 22 Partial adhesive layer 23 Thermoplastic adhesive 3 Insulating layer 4 2nd electrode layer 41 2nd electrode conductive layer 411 Conduction Adhesive layer 412 second electrode conductive sheet 42 conductive adhesive layer 5 electrode clip

Claims (11)

A first electrode layer having conductivity and liquid permeability,
An insulating layer disposed to face the entire surface of the first electrode layer and exhibiting conductivity due to the presence of a liquid that has passed through the first electrode layer;
The insulating layer is opposed via a have a second electrode layer having conductivity and tack on the entire surface of the first electrode layer,
A liquid detection sensor , wherein a surface of the second electrode layer opposite to the insulating layer is a surface that is in contact with an installation target, and has conductivity and adhesiveness . The first electrode layer includes:
2. The liquid detection sensor according to claim 1, wherein the plurality of openings through which the liquid passes have a first electrode conductive layer formed of a conductive paint. 3. The first electrode conductive layer,
The liquid detection sensor according to claim 2, wherein the opening is formed by intersecting the linear portions made of the conductive paint. The first electrode layer includes:
The liquid crystal display device further includes a partial adhesive layer that is disposed between the first electrode conductive layer and the insulating layer and has a plurality of openings through which the liquid that has passed through the first electrode conductive layer is transmitted. The liquid detection sensor according to claim 2 or 3 , wherein: The second electrode layer includes:
A second electrode conductive layer having one surface joined to the insulating layer and having conductivity;
2. The liquid detection sensor according to claim 1, further comprising: a conductive adhesive layer that is bonded to the other surface of the second electrode conductive layer and has adhesiveness at least in a thickness direction. . The second electrode conductive layer,
One side is bonded to the insulating layer, a conductive adhesive layer having conductivity at least in the thickness direction,
The liquid detection sensor according to claim 5, further comprising a second electrode conductive sheet having one surface adhered to the other surface of the conductive adhesive layer and having conductivity. The second electrode layer includes:
A second electrode conductive sheet in which a plurality of recesses are dispersedly arranged on the entire surface on the side opposite to the insulating layer side;
The liquid detection sensor according to claim 1, further comprising an adhesive stored in the concave portion. The second electrode layer includes:
A plurality of recesses distributed over the entire surface on the insulating layer side, a second electrode conductive sheet having a plurality of recesses distributed over the entire surface on the side opposite to the insulating layer,
An adhesive housed in the concave portion disposed on the insulating layer side of the second electrode conductive sheet,
2. The liquid detection sensor according to claim 1, further comprising: an adhesive accommodated in the recess arranged on a side of the second electrode conductive sheet opposite to the side of the insulating layer. 3.   9. The liquid detection sensor according to claim 8, wherein the second electrode conductive sheet has a mesh structure of a metal-plated fiber, and an adhesive buried in an opening of the mesh structure. The second electrode layer includes:
A second electrode conductive layer having one surface joined to the insulating layer and having conductivity;
2. The liquid detection sensor according to claim 1, wherein the liquid detection sensor has a plurality of adhesive portions that are dispersed and arranged on the entire other surface of the second electrode conductive layer and are formed of an adhesive. 3. The adhesiveness of the surface of the second electrode layer on the side opposite to the insulating layer side is adhesiveness that makes the liquid detection sensor detachable from an installation target. The liquid detection sensor according to claim 1.

Images