JP2014241128A - Touch sensor and touch sensor module - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a touch sensor and touch sensor module which can be applied to an existing IT device such as a smart phone and also to a portable terminal which can be used by being worn on a human body such as a wrist band and a smart watch.SOLUTION: A touch sensor is capable of touch sensing to, wherever possible, a curved surface part; has a configuration in which a whole surface of a base sheet is capable of sensing; and is configured to be a highly-conductive touch sensor so that an electric signal by the sensing can be speedily and smoothly transmitted to an integrated circuit chip, external control circuit, and the like.

Description

  The present invention is an invention of a touch sensor and a touch sensor module that can be applied not only to existing IT devices such as smartphones, but also to portable terminals that can be worn and used on the body, such as wristbands and smart watches.

  Conventionally, there have been inventions of Patent Documents 1 to 5 as inventions of portable terminals such as smart watches.

JP 2003-277513 A JP 2002-090479 A JP 2002-125256 JP 2003-046621 A JP2010-049583A Special publication 2012-519344

  However, since a portable electronic terminal such as a conventional smart watch can only have a display screen as small as 2 inches, not only the items that can be displayed are limited, but also various touches with a fingertip, such as an existing smartphone. Sensing was difficult. On the other hand, a main touch sensor module such as an existing smartphone is a touch sensor in which a cover glass substrate made of soda glass of 0.5 to 2.5 mm and a transparent conductive pattern layer are formed as shown in Patent Document 6. And a plate-like liquid crystal display panel, etc., and there is a problem that when it is worn on the body, it is heavy and cannot follow the shape of the body.

  Therefore, in the present invention, it is possible to perform touch sensing on a curved surface portion as much as possible, and a touch sensor having a structure capable of sensing the entire surface of the base sheet, and an electric signal by sensing is integrated circuit chip or external control The touch sensor has a high conductivity so that it can be transmitted to a circuit or the like at high speed and smoothly. Furthermore, the cover substrate and the display are made of flexible materials, so that the touch sensor module can be bent along the body, and the weight is greatly reduced, so that it can be easily worn on the body.

  That is, according to the first characteristic configuration of the present invention, the touch sensing pattern layer is formed when a touch sensing pattern layer is formed on one side or both sides of a base sheet, and the touch sensing pattern layer is formed on the outer side and along a cylinder having a curvature radius of 20 mm. An increase in the resistance value of the layer is within 20%, a routing circuit made of a conductive metal is formed on the base sheet and the touch sensing pattern layer, and a part of the routing circuit is exposed to the outside air. A portion exposed to the outside of the routing circuit is a connection terminal for mounting an integrated circuit chip or connecting to an external circuit, and a protective sheet that can be easily attached and detached is coated on the exposed connection terminal. It is a touch sensor.

  The second characteristic configuration of the present invention is that the touch sensing pattern is formed when a touch sensing pattern layer is formed on one side or both sides of the base sheet, and the touch sensing pattern layer is formed on the outer side and along a cylinder having a curvature radius of 20 mm. An increase in the resistance value of the layer is within 20%, a routing circuit made of a conductive metal is formed on the base sheet and the touch sensing pattern layer, and a part of the routing circuit is exposed to the outside air. A portion exposed to the outside air of the routing circuit is a connection terminal for mounting the integrated circuit chip or connecting to the external circuit, and the connection circuit is left exposed in an atmosphere with a relative humidity of 2 to 70%. This is a touch sensor having the structure described above.

  The third characteristic configuration of the present invention is that a frame portion does not exist in the three directions around the touch sensing pattern layer, and the entire base sheet sheet except the frame portion in the remaining one direction becomes a touch screen portion capable of sensing. This is a featured touch sensor. According to a fourth feature of the present invention, an amorphous or low crystalline metal oxide layer is formed on a base sheet, and the metal oxide layer is patterned by photolithography and etching to form a touch sensing pattern layer. It is the touch sensor characterized by having performed. A fifth characteristic configuration of the present invention is a touch sensor characterized in that crystallization is promoted by irradiating a far-infrared ray or plasma to a touch sensing pattern layer obtained by patterning the metal oxide layer.

  According to a sixth feature of the present invention, the touch sensing pattern is formed when a touch sensing pattern layer is formed on one side or both sides of a base sheet, and the touch sensing pattern layer is formed on the outer side and along a cylinder having a curvature radius of 20 mm. An increase in the resistance value of the layer is within 20%, a routing circuit made of a conductive metal is formed on the base sheet and the touch sensing pattern layer, and a part of the routing circuit is exposed to the outside air. A portion exposed to the outside air of the routing circuit is a connection terminal for mounting an integrated circuit chip or connecting to an external circuit, and the integrated circuit chip is directly mounted on the connection terminal left exposed or This is a touch sensor module to which a flexible printed circuit board for connection to an external circuit is connected.

  According to a seventh aspect of the present invention, there is provided a touch in which a cover base material having a thickness of 0.03 to 0.4 mm is formed on the surface of the touch sensor module, and a flexible display panel is provided on the back surface of the touch sensor module. It is a sensor module.

  An eighth characteristic configuration of the present invention is a touch sensor module in which the touch sensor module and the flexible display panel are stacked by direct bonding.

  A ninth characteristic configuration of the present invention is a touch sensor module for a portable electronic terminal that can be used by being worn on the body.

  According to the first and second feature configurations of the present invention, the touch sensor of the present invention has an increase in the resistance value of the touch sensing pattern layer of 20 when the touch sensing pattern layer is placed on the outer surface and along a cylinder with a curvature radius of 20 mm. Therefore, the resistance value does not increase so as to cause a problem even if it is worn around a wrist or arm having a larger radius of curvature than that. Therefore, there is an effect that the touch sensor can be attached to any part of the body and can be input to the curved surface part.

  In addition, since a routing circuit made of a highly conductive conductor metal is formed, the response speed of touch sensing is fast, and an integrated circuit chip is directly mounted on the conductor metal or directly connected to an external circuit, so the vicinity of the connection terminal interface There is an effect that the problem of variation in contact resistance and increase in resistance value, which are likely to occur in the case of, is not generated. In addition, since the conductor metal is covered with a protective sheet that can be easily detached, or placed in an atmosphere with a relative humidity of 70% or less with the connection terminal exposed, the conductor Even if the metal is left exposed, there is an effect that the problem of poor connection due to rust or corrosion does not occur.

  According to the third characteristic configuration of the present invention, the touch sensor of the present invention has no frame portion in the three directions around the touch sensing pattern layer, and can perform touch sensing on the entire surface of the base sheet except the frame portion in the remaining one direction. Since it can be set as the touch screen part of an area | region, there exists an effect which can expand a display screen to the size of the base sheet surface whole surface. Therefore, the number of items that can be displayed on the display screen can be increased, and various touch sensing can be performed with a fingertip or the like as in an existing smartphone.

  According to the fourth characteristic configuration of the present invention, the touch sensor of the present invention forms an amorphous or low crystalline metal oxide layer on a substrate sheet, and the metal oxide layer is patterned by photolithography and etching. The touch sensing pattern layer is used. Therefore, a touch sensor having a very high-definition touch sensing pattern layer can be obtained. According to a fifth feature of the present invention, the touch sensing pattern layer obtained by patterning the metal oxide layer is irradiated with far infrared rays or plasma to promote crystallization. Therefore, it can be a touch sensor with a very high-definition and low-resistance touch sensing pattern layer, so that sensing signals are fast and high-definition sensing is possible, and various touch sensing more than existing smartphones can be performed. There is a possible effect.

  According to the sixth characteristic configuration of the present invention, the touch sensor module of the present invention has the integrated circuit chip mounted directly on the connection terminals that are exposed or a flexible printed circuit board for connecting directly to an external circuit. Therefore, the contact resistance at the connection terminal becomes very low. Accordingly, since the sensing signal is fast and high-definition sensing is possible, there is an effect that it is possible to perform various touch sensing more than the existing smartphone. Further, since the increase in the resistance value of the touch sensing pattern layer is 20% or less when the touch sensing pattern layer is placed on the outer surface and along a cylinder having a curvature radius of 20 mm, the wrist, arm, etc. having a larger curvature radius than that. There is an effect that the resistance value does not increase so as to cause a problem even if it is wound around.

  According to the seventh characteristic configuration of the present invention, in the touch sensor module of the present invention, a cover base material having a thickness of 0.03 to 0.4 mm is formed on the surface of the touch sensor module, and the back surface of the touch sensor touch sensor module. Is provided with a flexible display panel. Accordingly, the total thickness is thinner and lighter than that of the conventional IT device, and the entire structure can withstand bending distortion, so that there is an effect that a touch sensor module having excellent flexibility can be obtained. Therefore, there is an effect that a touch sensor module that can be worn at any place on the body and can be input to the curved surface portion can be obtained.

  According to the eighth characteristic configuration of the present invention, the touch sensor module of the present invention has the touch sensor module and the flexible display panel laminated by direct bonding. Therefore, the air layer formed by the conventional touch sensor module stacking method is eliminated, the transmittance of the display portion of the touch sensor module can be improved and the reflectance can be reduced, and the visibility of the display screen can be improved. And even if the stress applied to the cover substrate from the outside is transmitted to the flexible display panel, the stress is dispersed throughout the flexible display panel, and the fear of breakage of the touch sensor module and the flexible display panel is reduced. There is also an effect.

  According to the ninth characteristic configuration of the present invention, the touch sensor module of the present invention is for a portable electronic terminal and can be used by being worn on the body. Therefore, there is an effect that it is possible to provide consumers with usage modes that are not found in conventional IT equipment.

  Hereinafter, embodiments of the touch sensor 100 and the touch sensor module 10 according to the present invention will be described with reference to the drawings. The touch sensor 100 of the present invention is a touch sensor for a portable electronic terminal that can be used by being worn on a body such as an arm, a palm, a foot, and clothes in addition to an existing IT device such as a smartphone (FIG. 4, FIG. 5) The touch sensing pattern layer 4 when the touch sensing pattern layer 4 is formed on one side or both sides of the base sheet 101, and the touch sensing pattern layer 4 is along the cylinder having a radius of curvature of 20 mm with the touch sensing pattern layer 4 as the outer side (FIG. 6). 4 is within 20%, a routing circuit 44 made of a conductive metal is formed on the base sheet 101 and the touch sensing pattern layer 4, and a part of the routing circuit 44 is exposed to the outside air. A connection terminal for mounting the integrated circuit chip directly or connecting to an external circuit at a location exposed to the outside air of the routing circuit 44 5 is covered with a protective sheet 46 that can be easily detached on the connection terminal 45 that is exposed before the connection (FIG. 1), or the relative humidity is 2 to 70 with the connection terminal exposed. % Of the composition placed in the atmosphere.

  The base sheet 101 is made of a thermoplastic resin, a curable resin that is cured by heat, ultraviolet rays, an electron beam, radiation, or the like, glass, ceramics, an inorganic material, or the like. Examples of thermoplastic resins include olefin resins such as polyethylene, polypropylene, and cyclic polyolefin, vinyl resins such as polyvinyl chloride, polymethyl methacrylate, and polystyrene, cellulose resins such as nitrocellulose and triacetyl cellulose, polycarbonate, polyethylene terephthalate, and poly Examples thereof include ester resins such as dimethylcyclohexane terephthalate and aromatic polyester, ABS resins, copolymer resins of these resins, and mixed resins of these resins. Examples of the curable resin include an epoxy resin and a polyimide resin. These resins and the like may be a single material, or may be an alloy or a multilayer product.

  The base sheet 101 may be a polarizing film such as a linearly polarizing film or a retardation film. When a polarizing film is used, there is an advantage that external light reflection and gloss on the film surface such as the touch sensing pattern layer 4 can be reduced by the polarizing effect of the polarizing film. As an example of a polarizing film, the film which made the polyvinyl alcohol layer of a core material adsorb | suck iodine etc., the acetylcellulose layer was formed in the both surfaces, and processed, such as antifouling and light leakage suppression, is mentioned.

  The touch sensing pattern layer 4 is a layer that performs a sensing function for detecting an operation input by a consumer using a mobile terminal, and does not cause a problem even if it is worn on the body and subjected to bending stress or load. Need flexibility. The operation that is most subjected to bending stress and load when worn on the body is an operation of winding along the wrist or arm. The wrist and arm sizes vary depending on age, sex, etc., but on average, the curvature radius of the curved surface is about 20 to 50 mm. Therefore, the flexibility required for the touch sensing pattern layer 4 is that the resistance value increases in a test when the touch sensing pattern layer 4 is placed on the outer surface and along a cylinder having a curvature radius of 20 mm as shown in FIG. This is a non-problematic range, which is within 20%. The number of times along the test as shown in FIG. 6 is one.

  The touch sensing pattern layer 4 is preferably made of a transparent material with as low resistance as possible. Examples include metal oxides such as tin oxide, indium oxide, antimony oxide, zinc oxide, cadmium oxide, and indium tin oxide (ITO), and ultrafine conductor fibers (metals) made of conductive metal or carbon. Transparent conductive film containing nanofibers, metal nanowires, carbon nanotubes, etc.), transparent conductive film that is formed by patterning or self-organizing conductive metal into fine lines that cannot be visually confirmed, and appearing transparent in appearance And a thiophene-based conductive polymer such as PEDOT (polyethylenedioxythiophene) and a transparent conductive film made of graphene.

  The metal oxide layer is a non-crystalline or low-crystalline film at the time of film formation, and is a type of film that is appropriately crystallized later, and the film thickness is preferably about 10 to 500 nm. From the viewpoint of optical properties / conductivity, the ultrafine wire conductor fiber preferably has a cross-sectional diameter of 10 to 200 nm and an aspect ratio of 10 to 100,000, and is contained in a resin film having a thickness of about 0.5 to 30 μm. Good. As a transparent conductive film obtained by patterning a conductor metal on a thin wire that cannot be visually confirmed, a conductor metal such as gold, silver, copper, tin, nickel, aluminum, palladium, etc., having a thickness of about 0.5 to 30 μm, a wire A lattice pattern or a honeycomb pattern having a width of about 0.2 to 7 μm and an aperture ratio (ratio in which a conductor metal pattern per unit area is not formed) of 90% or more is preferable.

  When the touch sensing pattern layer 4 is formed of a metal oxide layer, the patterning means may be a method of patterning a resist by a general-purpose printing method or the like, but the touch sensor 100 of the present invention has a high definition. Since patterning is necessary, a photolithography method (that is, a method in which a photoresist is applied to the entire surface of the metal oxide layer, a portion to be patterned is exposed and cured, an uncured portion is removed, and patterning is performed) On the contrary, a method of exposing and softening a portion to be removed and removing the softened portion of the photoresist) is preferable. After patterning the resist, the metal oxide layer where the resist is not placed is removed by etching to form the touch sensing pattern layer 4.

  Since the metal oxide layer can be formed into a film having better resistance if it is formed from a crystallized film from the beginning, in general, a metal oxide layer crystallized from the beginning is usually formed. Such a crystallized metal oxide layer is difficult to remove by an etching method and is difficult to make the touch sensing pattern layer 4 into a high-definition pattern. In addition, since the metal oxide layer crystallized from the beginning is relatively hard and brittle, it may be a film that cannot ensure the flexibility described above depending on the thickness and manufacturing method. On the other hand, the resistance value of the amorphous or low-crystalline metal oxide layer is high as it is, and the detection accuracy and detection sensitivity of touch sensing may be weakened. Since it is possible to easily reduce the resistance if it is appropriately crystallized, it is preferable.

  The term “non-crystalline or low crystalline” is not limited to a completely amorphous material, but also includes a material having a small amount of a crystalline component. Therefore, in the present invention, the X-ray analysis profile is taken and the touch sensing pattern layer is used even when a clear peak of the X-ray analysis intensity indicating crystallization is not seen, and even when the peak is slightly seen. 4 is immersed in hydrochloric acid having a concentration of 5% by weight for 15 minutes, washed with water and dried, and when the resistance between terminals between 15 mm and 2 is measured, the resistance between terminals rises 10 times or more. In such a case, it is defined as “amorphous or low crystalline”. This is because if the metal oxide film is sufficiently crystallized, the film is hardly attacked even by immersion in hydrochloric acid under the above conditions, and the resistance between terminals does not increase so much.

  As a method for forming the metal oxide layer, various sputtering methods such as a DC magnetron sputtering method, an RF sputtering method, and a pulse sputtering method, a vacuum deposition method, an ion plating method, a plating method, and the like can be given. Alternatively, it may be formed by dissolving or dispersing in a solvent to form a liquid state, spraying or dip coating, and then dispersing the solvent.

  In particular, when the metal oxide layer is formed into a non-crystalline or low-crystalline film by a sputtering method, the base sheet 101 is preheated and evacuated to a high vacuum in order to make the subsequent crystallization easy to control. It is good to form by reactive sputtering film formation which introduce | transduced oxidizing agents, such as inert gas and oxygen gas, such as argon, in the apparatus.

  Resist materials for patterning the metal oxide layer include vinyl-based, acrylic-based, urethane-based, alkyd-based, epoxy-based, polyester-based, cellulose-based resins, and the thickness is about 1 to 50 μm. preferable. The method for forming the resist film may be a normal printing method such as screen printing, offset printing, gravure printing, flexographic printing, or a coating method with various coaters. Examples of the etching solution for etching the metal oxide layer include ferric chloride aqueous solutions, strong acidic aqueous solutions such as high concentration hydrochloric acid, nitric acid, sulfuric acid, and strong alkaline aqueous solutions such as caustic soda and caustic potash. .

  As mentioned above, although the method using a resist was described as a means for patterning the touch sensing pattern layer 4, there is also a method of patterning using a laser irradiation machine without using a resist. That is, a part of the film formed by the energy of the laser beam is burned out, or the ultrafine conductor fibers in the film are disconnected to insulate the film. In particular, in the latter case, since there is almost no distinction in appearance between the disconnected conductor fiber and the conductive conductor fiber, there is an effect of hiding the pattern of the touch sensing pattern layer 4 (so-called bone-viewing prevention effect).

  The touch sensing pattern layer 4 formed by the above method may be a single layer or a plurality of layers. In the case of a plurality of layers, the touch sensing pattern layer 4 may be provided on both surfaces of the substrate sheet 101 or a plurality of substrates. Each sheet 101 may be provided with a single touch sensing pattern layer 4 and laminated such that the touch sensing pattern layer 4 is formed on the same side.

  However, when used by being worn on the body, the touch sensor 100 is often used in a bent state, and the pitch of the touch sensing pattern layer 4 is likely to change longer than before being bent. If the touch sensing pattern layer 4 is a single layer, the detection accuracy and detection sensitivity of the touch sensing are lowered and a defect is likely to occur at the extended portion.

  In that respect, if a plurality of touch sensing pattern layers 4 are provided, even if the touch sensing pattern layer 4 on one side is stretched to increase the pitch, the pitch of the touch sensing pattern layer 4 on the other side is The touch sensing pattern layer 4 can be made to compensate for a decrease in the detection accuracy and detection sensitivity of the touch sensing pattern layer 4 at the stretched portion by shortening the same or conversely (FIG. 7). Is more preferably a plurality of layers than a single layer.

  The electrical signal detected by the touch sensing pattern layer 4 is generally transmitted to the integrated circuit chip or the external circuit through the connection terminal 45 through the routing circuit 44 formed in the outer frame frame portion surrounded by the four surrounding directions. Is done. The routing circuit 44 formed in the frame portions in the four surrounding directions is indispensable in terms of configuration, but the larger the proportion of the area occupied by the frame portion, the narrower the area of the display screen that can be touch-sensed. Therefore, there is a trade-off relationship with market needs to make the display screen area where touch sensing is possible as large as possible. In particular, in the case of a portable electronic terminal applied to the touch sensor 100 of the present invention, the market needs are much higher because the display screen itself originally had a small problem.

  Therefore, the pattern of the touch sensing pattern layer 4 has no frame portion in the three surrounding directions and the remaining one direction than the one formed in the central portion surrounded by the general outer frame frame portion. It is preferable that the entire surface of the base sheet 101 excluding the frame portion 60 is formed into a pattern configured to be a touch screen portion of the region 40 capable of touch sensing (FIG. 3). If comprised in this way, the substantially whole surface of the base material sheet 101 becomes a touch screen part, and there exists an advantage which can enlarge the area | region of the display screen which can be touch-sensed to the maximum. In particular, with the conventional touch sensor, the display screen of the mobile terminal that is finally manufactured for the frame portions on both sides inevitably had to be very long and unsightly, but the frame portions on both sides were If it disappears, the display screen of the mobile terminal that will be finally produced can be close to a balanced shape (FIG. 4).

  Furthermore, since the base sheet 101 and the touch sensing pattern layer 4 have the flexibility described above, not only the flat part but also the curved surface can be used as a touch screen part, so that the touch sensor of the portable electronic terminal attached to the body can be used. A large area of the module 10 can be set as a region 40 capable of touch sensing (FIG. 4). Therefore, the area 40 that can be touch-sensed is greatly enlarged and the number of items that can be displayed is increased, so that various touch-sensings can be performed with a fingertip or the like as in an existing smartphone.

  The routing circuit 44 is a layer for transmitting the electrical signal detected by the touch sensing pattern layer 4 through the connection terminal 45 to the integrated circuit chip and the external circuit smoothly at high speed, and is a highly conductive gold for the purpose of transmitting at high speed. , Composed of conductive metal such as silver, copper, aluminum, nickel, palladium. The routing circuit 44 may be formed by a combination of the above-described photolithography, printing method, and etching method. The thickness may be appropriately set at about 0.1 to 50 μm. The conductor metal may partially contain other materials such as additives and resins.

  The connection terminal 45 of the routing circuit 44 is configured so that the conductor metal of the routing circuit 44 is exposed to the outside as it is. If the conductor metal is left exposed to the outside air, the conductor metal may rust or corrode due to moisture from the outside air, resulting in poor connection. Therefore, the connection terminal 45 is covered with a conductive film such as carbon paste. In general, however, rust prevention and corrosion prevention are performed, but if this is done, the contact resistance at the interface of the connection terminal 45 will inevitably increase, and the electrical signal detected by the touch sensing pattern layer 4 will be generated at high speed. This is because there is a possibility of hindering smooth transmission to an integrated circuit chip or an external circuit.

  Then, instead of being covered with a conductive film such as carbon paste, the connection terminal 45 is covered with a protective sheet 46 that can be easily detached or placed in an atmosphere with a relative humidity of 2 to 70% with the connection terminal 45 exposed. To prevent rust and corrosion. In a touch sensor product with a large lot quantity, the lead time from when the routing circuit 44 is formed for some of the manufactured touch sensors to when an integrated circuit chip is mounted on the connection terminal 45 becomes longer. In such a case, if no measures are taken with the connection terminals 45 exposed to the outside air, the touch terminals in a state where the connection terminals 45 are rusted or corroded are partially included and randomly included. The labor and cost of sorting the products into usable products and unusable products become very large, causing problems such as a decrease in total productivity and a significant increase in production costs. Even if countermeasures such as conformal coating are taken after mounting etc., once the rust and corrosion start, it will proceed at an accelerated rate, so deterioration in quality is unavoidable, so countermeasures against such rust and corrosion are handled by the touch sensor itself. This is because it must be done in advance.

  The protective sheet 46 that can be easily attached and detached serves to protect the connection terminals 45 exposed to the outside air from rust and corrosion. Therefore, it is necessary to cover the connection terminals 45 as soon as possible after the routing circuit 44 is formed. . The protective sheet 46 that can be easily detached is not required to have optical characteristics or electrical characteristics, but has a water vapor barrier property that blocks the moisture of the outside air from the necessity for the above-mentioned role and an appropriate temporary adhesive property that facilitates the removal. Need.

The preferable water vapor barrier property of the protective sheet 46 that can be easily detached is that the water vapor permeability for 24 hours in an atmosphere at a temperature of 40 ° C. and a relative humidity of 90% is within 5 g / m ² , and the preferred temporary adhesive property is JIS-K. In the 180 degree peel test method specified in -6854, the peel speed is 20 mm / sec and the weight is 10 to 500 g per 25 mm width. Examples of the sheet material of the protective sheet 46 include a plastic film such as polyvinylidene chloride and polytetrafluoroethylene having a thickness of about 10 to 500 μm, and an opaque foil such as an aluminum foil. Further, even a sheet material having a water vapor barrier property less than these materials can be used as the protective sheet 46 by providing a water vapor barrier layer having a water vapor permeability of about 1 × 10 −2 to 10 −8 g / m ² / d. .

  As a method of placing in an atmosphere having a relative humidity of 2 to 70%, a method of placing the touch sensor 100 in a container or a room capable of maintaining an atmosphere of a predetermined temperature and relative humidity, or a method of sealing and vacuum packaging the touch sensor 100 Etc. Here, the relative humidity is a partial pressure of the water vapor pressure with respect to the saturated water vapor pressure, and the saturated water vapor pressure is a value of a saturated water vapor pressure table described in JIS28806. For example, when the average water vapor amount in 1 m ↑ 3 in the atmosphere measured at a temperature of 30 ° C. is 15.2 g, the saturated water vapor amount at the temperature of 30 ° C. is 30.4 g / m ↑ 3, so the relative humidity is 15 .2 ÷ 30.4 × 100 = 50.0%.

  The lower the relative humidity, the better. However, in order to make the relative humidity less than 2%, it is difficult to realize unless the ambient temperature exceeds 50 ° C. However, it is not preferable to place the touch sensor at an ambient temperature exceeding 50 ° C. for a long time because it may cause thermal deterioration of the touch sensor. On the other hand, if the ambient temperature is less than 10 ° C., condensation tends to occur and there is a problem. Therefore, when using the method of placing the touch sensor 100 in a container or a room, it is preferable to place the touch sensor 100 in a container or room that can maintain an atmosphere having a temperature of 10 to 50 ° C. and a relative humidity of 2 to 70%.

In the vacuum packaging method, since moisture is removed at the time of packaging, there is little fear of rusting in a short period of time. However, since the moisture of the outside air passes through the packaging material and penetrates into the interior with time, the temperature is 40 ° C. and the relative humidity is 90 It is preferable to package using a packaging material having a water vapor barrier property with a water vapor permeability of 20 g / m ^{2 or} less within a 24% atmosphere. And, it is more preferable to fill the packaged interior with an inert gas such as nitrogen gas in advance because it prevents intrusion of moisture from the outside air.

  In addition to the connection terminals 45 on the touch sensing pattern layer 4 and the routing circuit 44, a thermoplastic resin such as a cyclic olefin resin, a polyether sulfone resin, a polyarylate resin, an amorphous polyolefin resin, It is preferable to form a part or all of the anticorrosive coating layer 30 made of a thermosetting resin such as epoxy, urethane or acrylic, or an ultraviolet curable resin such as urethane acrylate or cyanoacrylate (see FIG. 1). The anticorrosive coating layer 30 needs to have strong adhesiveness and electrical insulation in addition to the antirust effect on the touch sensing pattern layer 4 and the routing circuit 44. The rust-proof coating layer 30 may be formed by a general printing method such as gravure, screen, or offset, as well as a method using various coaters, a method such as painting, and dipping. The anticorrosive coating layer 30 may be a separately manufactured film. In that case, the anticorrosive coating layer 30 may be formed by sticking with a heat laminate or a laminate via an adhesive / adhesive.

  Next, a touch sensor module using the touch sensor 100 of the present invention will be described. The touch sensor module 10 of the present invention is attached / detached when a protective sheet 46 that can be easily attached / detached is coated on the connection terminal 45 of the touch sensor 100, and is directly attached to the connection terminal 45 exposed to the outside air immediately after the attachment / detachment. The integrated circuit chip 46 is mounted by a method such as soldering or a flexible printed board for connection to an external circuit is connected. Therefore, since the contact resistance at the connection terminal 45 is low, an electrical signal can be transmitted to an integrated circuit chip or an external circuit faster and more smoothly than an IT device such as a conventional smartphone.

  The surface of the touch sensor 100 is covered with a cover base material 1 having a thickness of 0.03 to 0.4 mm, and the back surface of the touch sensor 100 is provided with a flexible display panel 8 (FIG. 2). Therefore, since the total thickness is thin and light, and the entire structure can withstand bending strain, it can be worn anywhere in the body (FIG. 5), and touch sensing on a curved surface is also possible (FIG. 4).

  Note that the exposed portion of the conductive metal of the routing circuit 44 in the connection terminal 45 may be a part of the connection terminal 45. For example, when a protective film formed in an island shape like an ultrathin tin film is formed on the surface of the connection terminal 45, the surface of the connection terminal 45 is routed and the conductor metal itself of the circuit 44 is exposed in some places. In the case of a tin film, tin oxide itself is highly conductive even when oxidized by moisture in the outside air, so contact resistance that is a concern when forming a protective film with a conductive film such as the carbon paste described above. This is because an electrical signal can be transmitted to an integrated circuit chip or an external circuit smoothly at high speed.

  Examples of the cover substrate 1 include chemically tempered glass, sapphire glass, a plastic film having a hard coat layer formed on the surface, and a high-hardness plastic film in which inorganic particles are formed in an island shape on an organic polymer matrix. . If the thickness is greater than 0.4 mm, the weight is heavy and it is difficult to bend it, and it cannot be used by being worn on the body. Moreover, since it cannot be made into a roll shape, it becomes impossible to laminate | stack with the touch sensor 100 which is mentioned later by a roll-to-roll system. On the other hand, when the thickness is less than 0.03 mm, the performance as a cover base material such as wear resistance and scratch resistance is lowered, and wrinkles are easily generated, and it is difficult to neatly stack with the touch sensor 100.

  Examples of the chemically strengthened glass include borosilicate glass having an alumina content of 8% or more. In a salt bath containing 85% by weight or more of potassium nitrate and a bath temperature of 300 to 600 ° C., 1 aluminosilicate glass or the like is used. It is soaked for ˜15 hours to release the sodium ions contained in the glass, and the chemical strengthening is performed by, for example, taking in potassium ions instead. Examples of the production method include a fusion method (overflow method) and a float method.

  Sapphire glass includes hexagonal single crystal lattice glass with alumina dissolved, chemical strengthening is not required, it is heat resistant, resistant to strong acids and other chemicals, and has a pencil hardness of 9H. Is preferred. Examples of the production method include Czochralski method, Kyropoulos method, heat exchange method, EFG method and the like.

  Plastic films with a hard coat layer formed on the surface include olefin resins such as polyethylene, polypropylene and cyclic polyolefin, vinyl resins such as polymethyl methacrylate and polystyrene, cellulose resins such as nitrocellulose and triacetyl cellulose, and polycarbonate. UV curing such as epoxy-based, urethane-based, acrylic-based thermosetting resins, urethane acrylate-based, cyanoacrylate-based plastic films such as polyethylene terephthalate, polydimethylcyclohexane terephthalate, aromatic polyester, etc. And a hard coat layer made of a mold resin. The plastic film having a hard coat layer formed on the surface preferably has a pencil hardness of 3H to 9H. This is because if it is less than 3H, the scratch resistance is insufficient, and if it is 10H or more, cracking tends to occur when bent.

  A high-hardness plastic film in which inorganic particles are formed in an island shape in an organic polymer matrix is formed in an island shape so that inorganic particles 7 having an average diameter of about 0.5 to 20 nm are uniformly distributed in the organic polymer matrix 6. (FIG. 8). Inorganic particles with an average diameter of less than 0.5 nm tend to aggregate and are more often distributed unevenly. When the diameter is small, the inorganic particles 7 are buried in the film of the organic polymer matrix 6 and the inorganic particles 7 have high hardness and high resistance. This is because the advantage of tearing properties cannot be exhibited. On the other hand, the inorganic particles having a diameter of more than 20 nm greatly obstruct the surface smoothness of the cover base material 1, and if the proportion of the inorganic particles is large, the surface roughness of the cover base material 1 is large. Becomes much larger and causes defects such as bubble chewing.

  In addition, if the inorganic particles 7 are not uniformly distributed and are distributed in an overly dense manner in the matrix 6, the portion becomes brittle and easily damaged by impact, and conversely, the portion where the inorganic particles 7 become depopulated has a low surface strength. It becomes easy to produce the malfunction which becomes easy to get scratched. Furthermore, when the thickness is more than 0.4 mm, the film cannot be continuously cut into individual pieces, and when the thickness is less than 0.03 mm, the material itself is broken and cannot be used.

  The flexible display panel 8 is a display having a radius of curvature of 20 mm and a thickness of 2 mm or less that does not break even when bent. Specifically, a flexible organic electroluminescence (organic EL) display panel, a flexible liquid crystal display panel, a flexible electrophoretic display panel, etc. Is mentioned. In particular, the organic EL display panel is preferable in that the light emitting layer and the like are made of a thin and flexible solid laminated film and can realize high flexibility and thinning.

  As a method of laminating the cover substrate 1, the touch sensor 100 and the flexible display panel 8, for example, an ultraviolet curable optical adhesive is applied to the entire surface of the cover substrate 1 or the flexible display panel 8 or both surfaces of the touch sensor 100. And a method in which the optical adhesive is cured with ultraviolet rays by irradiating with ultraviolet rays. Alternatively, an adhesive optically transparent optically transparent double-sided tape or a tape on which a pressure-sensitive adhesive is formed is applied to the entire surface of the cover substrate 1 or the flexible display panel 8 or the entire surface of the touch sensor 100. A method of pasting and laminating in advance is also included.

  In particular, the touch sensor 100 and the flexible display panel 8 are preferably laminated by direct bonding (overall bonding). By doing so, there is no air layer that is formed by the conventional partially pasted lamination method, and not only can the transmittance of the display portion of the touch sensor module 10 be improved and the reflectance reduced, but also from the outside. Even if the stress applied to the cover substrate 1 is transmitted to the flexible display panel 8 through the touch sensor 100, the stress is dispersed throughout the flexible display panel 8, and the concern about the damage of the flexible display panel 8 is further reduced. This is because there is an effect.

  The touch sensor 100 and the cover substrate 1 may be stacked and the touch sensor 100 and the flexible display panel 8 may be stacked after being cut into respective predetermined sizes. It is preferable that the respective layers are transported continuously from the state of rolls, and are laminated by a method of simultaneously laminating them between the metal roll 25 and the rubber roll (so-called roll-to-roll method) (FIG. 9). And finally, it is good to cut into a predetermined size.

  In addition, you may provide the decoration layer 3 for concealing the routing circuit 44 formed in the frame part 60 etc. of the touch sensor 100 in either the cover base material 1 or the touch sensor 100. The decorative layer 3 is preferably formed by a transfer method using the transfer sheet 20 (FIG. 10). Even if the decorative layer 3 is formed in a thick film with large surface irregularities, the surface is leveled by the subsequent formation of the adhesive layer and the transfer pressure, and the level difference is reduced. This is because there is an effect of reducing air bubbles generated during the lamination. The transfer sheet used for the transfer method is preferably provided with a colorless and transparent adhesive layer ink layer on the decorative layer 3.

  Even if the unevenness of the surface of the formed decorative layer 3 is large, as long as the surface roughness of the base material of the transfer sheet is reduced and the smoothness of the adhesive layer ink is improved, the decorative layer 3 is decorated by the leveling of the adhesive layer ink. This is because there are almost no steps in the thickness of the layer 3 and the surface irregularities of the decorative layer 3 are reduced. Therefore, if comprised in that way, the unevenness | corrugation of the surface of the decoration layer 3 will not produce troubles, such as influence on the touch sensing pattern layer 4 grade | etc., Bubble chewing. As a result, there is no problem even if the thickness of the decorative layer 3 is increased, so that the decorative layer 3 can be used even in colors that are not concealed, and the appearance of the display screen of the portable electronic terminal is excellent in design. There is an effect that the appearance can be made.

  The decorative layer 3 is made of a vinyl resin, a polyamide resin, a polyester resin, an acrylic resin, a polyurethane resin, a polyvinyl acetal resin, an alkyd resin, or the like as a binder, and is colored with an appropriate color pigment or dye. It is recommended to use colored ink contained as an agent. As a method for forming the decoration layer 3, a normal printing method such as screen printing, offset printing, gravure printing, flexographic printing, or the like may be used. The thickness of the decorative layer 3 is generally about 0.5 to 10 μm. .

    The adhesive layer ink layer may be formed using a colorless and transparent ink having a polyamide resin, an acrylic resin, a cycloolefin resin, or the like as a binder. However, since these single resin systems are difficult to adhere to the cover base material 1, particularly the inorganic particles 7, it is preferable to add an adhesion auxiliary additive such as a silane coupling agent. As a forming method, a method using various coaters such as a direct coater method, a lip coater method, and a reverse coater method that can increase the thickness other than the normal printing method may be used. The thickness of the adhesive layer ink layer 22 is preferably dry and thicker than the thickness of the decorative layer 3 in order to reduce the level difference due to the thickness of the decorative layer 3. In addition, since leveling properties on the surface of the adhesive layer ink layer are also required, it is preferable to add a leveling agent such as a modified silicon type to the adhesive layer ink.

It is sectional drawing which shows an example of the touch sensor which concerns on the 1st characteristic structure of this invention. It is sectional drawing which shows an example of the touch sensor module which concerns on the 7th characteristic structure of this invention. It is a top view which shows an example of the touch sensor which concerns on the 3rd characteristic structure of this invention. It is a conceptual diagram which shows an example of the touch sensor module which concerns on the 6th characteristic structure thru | or 9th characteristic structure of this invention. It is a conceptual diagram which shows an example of the location with which the body of the touch sensor module which concerns on the 9th characteristic structure of this invention is mounted | worn. It is sectional drawing which shows an example of the state where the touch sensor which concerns on the 1st characteristic structure of this invention and the 2nd characteristic structure was put along the cylinder. It is a conceptual diagram which shows an example of the state which bent the cross section of the touch sensor which concerns on the 1st characteristic structure thru | or 5th characteristic structure of this invention into the curved surface. It is a perspective view which shows an example of the cover transparent which comprises the touch sensor module which concerns on the 7th characteristic structure thru | or 9th characteristic structure of this invention. It is sectional drawing which shows an example of the manufacturing method of the touch sensor module which concerns on the 7th characteristic structure of this invention thru | or 9th characteristic structure. An example of the manufacturing method of the cover base material used for the touch sensor module which concerns on the 7th characteristic structure thru | or 9th characteristic structure of this invention is shown.

DESCRIPTION OF SYMBOLS 1 Cover base material 3 Decorating layer 4 Touch sensing pattern layer 6 Matrix 7 Inorganic particle 8 Flexible display panel 10 Touch sensor module 20 Transfer sheet 25 Metal roll 26 Rubber roll 30 Anticorrosive coating layer 40 Touch sensing area 44 Lead-out circuit 45 Connection terminal 46 Protective sheet that can be easily detached 47 Integrated circuit chip 60 Frame portion 100 Touch sensor 101 Base sheet 200 Cylinder

Claims (9)

  When the touch sensing pattern layer is formed on one side or both sides of the base sheet, and the touch sensing pattern layer extends along the cylinder having a curvature radius of 20 mm with the touch sensing pattern layer as an outer side, an increase in the resistance value of the touch sensing pattern layer is within 20%. A routing circuit made of a conductive metal is formed on the touch sensing pattern layer, and a part of the routing circuit is exposed to the outside air, and the portion of the routing circuit exposed to the outside air is mounted with an integrated circuit chip Or a touch sensor that is a connection terminal for connecting to an external circuit, and a protective sheet that is easily attached and detached is coated on the exposed connection terminal. When the touch sensing pattern layer is formed on one side or both sides of the base sheet, and the touch sensing pattern layer extends along the cylinder having a curvature radius of 20 mm with the touch sensing pattern layer as an outer side, an increase in the resistance value of the touch sensing pattern layer is within 20%. A routing circuit made of a conductive metal is formed on the touch sensing pattern layer, and a part of the routing circuit is exposed to the outside air, and the portion of the routing circuit exposed to the outside air is mounted with an integrated circuit chip Or a touch sensor which is a connection terminal for connection to an external circuit and is placed in an atmosphere having a relative humidity of 2 to 70% with the connection terminal exposed.   3. The touch screen portion according to claim 1, wherein no frame portion exists in the three directions around the touch sensing pattern layer, and the entire surface of the base sheet excluding the frame portion in the remaining one direction becomes a sensing touch screen portion. The touch sensor according to any one of the above.   An amorphous or low crystalline metal oxide layer is formed on a substrate sheet, and the metal oxide layer is patterned by photolithography and etching to form a touch sensing pattern layer. Item 4. The touch sensor according to any one of Items 3 to 3.   The touch sensor according to claim 4, wherein the touch sensing pattern layer obtained by patterning the metal oxide layer is irradiated with far infrared rays or plasma to promote crystallization.   When the touch sensing pattern layer is formed on one side or both sides of the base sheet, and the touch sensing pattern layer extends along the cylinder having a curvature radius of 20 mm with the touch sensing pattern layer as an outer side, an increase in the resistance value of the touch sensing pattern layer is within 20%. A routing circuit made of a conductive metal is formed on the touch sensing pattern layer, and a part of the routing circuit is exposed to the outside air, and the portion of the routing circuit exposed to the outside air is mounted with an integrated circuit chip Or a touch sensor module that is a connection terminal for connecting to an external circuit, and an integrated circuit chip is directly mounted on the connection terminal that is exposed or connected to an external circuit.   A touch sensor module, wherein a surface of the touch sensor module according to claim 6 is coated with a cover base material having a thickness of 0.03 to 0.4 mm, and a flexible display panel is provided on the back surface of the touch sensor.   The touch sensor module according to claim 7, wherein the touch sensor module and the flexible display panel are laminated by direct bonding.   The touch sensor module for portable electronic terminals according to any one of claims 6 to 8, wherein the touch sensor module can be used by being worn on a body.

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