JP2007108241A - Substrate for electrode - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a substrate for an electrode for a flexible display, and especially, the substrate for the electrode having texture-like paper. <P>SOLUTION: Disclosed is the substrate for the electrode which has the electrode on its surface and also has a display element arranged thereupon, and is used for display device, the substrate for the electrode being one kind selected from among paper, synthetic paper, coated paper having a coating layer provided on paper or synthetic paper, and a stacked sheet formed by sticking paper and/or synthetic paper and having ≤5.0 μm surface roughness, based on JIS P 8151 on the side of the substrate for the electrode where the electrode is provided. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an electrode substrate for a flexible display, and more particularly to an electrode substrate having a paper-like texture.

  In recent years, development competition regarding flat panel displays such as liquid crystal displays, plasma displays, and organic EL displays has become increasingly intense. In these displays, a display element (for example, a nematic liquid crystal material in a liquid crystal display, a rare gas in a plasma display, etc.) is sandwiched between two electrodes, and depending on whether an electric field is applied between the electrodes or a current is passed, Controls display on / off.

  Usually, a glass substrate is used as the electrode substrate. Glass substrates have been generally used for reasons such as uniform thickness, low coefficient of linear expansion, and high heat resistance. As an electrode, most recently, an active matrix method in which a switch is provided for each pixel has been mostly used, and hydrogenated amorphous silicon or low-temperature polysilicon obtained by annealing hydrogenated amorphous silicon with a laser is used as a switch element for the active matrix. It has been. When amorphous silicon is deposited on the substrate, the substrate is heated to about 400 ° C. Therefore, a normal plastic film cannot withstand the film forming temperature as described above. A glass substrate has heat resistance to high temperatures, and can withstand laser annealing for forming low-temperature polysilicon. However, since a glass substrate cannot be bent as a matter of course, it is not suitable for an electrode substrate for a display that can be bent (so-called flexible display). In addition, since it is brittle and weak against impact, it is not suitable for an electrode substrate for a mobile display or a touch panel display.

  One candidate for the next-generation flat panel display as described above is a flexible display. Generally, a glass substrate cannot be used as an electrode substrate for a flexible display, and a plastic film is usually used. Although the heat resistance of plastic films has improved year by year, it is still difficult to form amorphous silicon on plastic films. Therefore, in recent years, research on using an organic transistor as a switch element has been actively conducted in order to respond flexibly. (See, for example, CD Dimitrakopoulos, DJ Mascaro, IBM J. RES. & DEV., 45 (1), 2001 (Non-patent Document 1).) Recently, the performance of organic transistors has been further improved. As mobility values, those exceeding the mobility of amorphous silicon have been reported.

  However, flexible displays using plastic films as electrode substrates are still far from being paper-like. In particular, a new display method called “electronic paper” characterized by being paper-like (see, for example, US Pat. No. 6,175,584 (Patent Document 1), US Pat. No. 4,126,854 (Patent Document 2)) .), The use of a plastic film for the electrode substrate halves its characteristics. This is because electronic paper is particularly required to have a paper texture.

  A proposal has been made to use a paper-like flexible substrate as an electrode substrate for a display (see, for example, Japanese Patent Laid-Open No. 2002-221918 (Patent Document 3) and Japanese Patent Publication No. 11-502950 (Patent Document 4)). .) The proposal is an electronic book having a page display that is electronically addressable on the surface of a flexible substrate such as paper. However, in the above method, the surface of the substrate is not subjected to a treatment for improving the adhesion with the conductive material or the semiconductor material. When general paper is used untreated, the surface irregularities are larger than those of a glass substrate or a plastic substrate, so that the thickness of the conductive material layer necessary for obtaining effective conductivity is also increased. Also, the adhesion between the paper and the conductive material is poor. As a result, the conductive material is likely to crack when bent, and the resistance value may increase remarkably or may be broken in the worst case.

US Patent No. 6017584 US Pat. No. 4,126,854 JP 2002-221918 (page 2-3) JP 11-502950 A (page 2-7) C. D. Dimitrakopoulos, D.M. J. et al. Masaro, IBM J.M. RES. & DEV. 45 (1), 2001

  An object of the present invention is to improve the above-mentioned drawbacks of the prior art and provide an electrode substrate having a texture like paper.

The present invention for solving the above problems includes the following aspects.
(1) An electrode substrate having an electrode on its surface, a display element disposed thereon, and used for a display device, wherein the electrode substrate is coated on paper, synthetic paper, paper or synthetic paper The surface roughness based on JIS P 8151 on the side where the electrodes of the electrode substrate are provided is one type selected from coated paper and a laminated sheet bonded with paper and / or synthetic paper. An electrode substrate having a thickness of 0.0 μm or less.
(2) The electrode substrate according to claim 1, which is used for a display device including a transparent front plate on which electrodes are further arranged on the display element.
(3) The electrodes for supplying electricity to the electrode substrate and the electrodes connected to the ground are alternately arranged so that the direction of the supplied electricity is parallel to the plane direction of the electrode substrate. Item 2. The electrode substrate according to Item 1.

  (4) The light reflection characteristic measured according to JIS Z 8741 on the surface of the electrode substrate is that the light source and the light receiver are opposite to each other across the normal line at the measurement point on the electrode substrate. The angle with respect to the normal of the incident light from the light source is set to 45 °, the angle with respect to the normal at the measurement point of the light receiver is R1 (%) at 45 °, and the reflectance at 50 °. R2 (%), and when the reflectance at 40 ° is R3 (%), the difference between R1 and R2 and the difference between R1 and R3 is less than 50%, (1) to (3) The electrode substrate according to any one of items 1).

(5) The electrode substrate according to any one of (1) to (4), wherein the electrode substrate has a synthetic resin layer on the electrode side.
(6) The electrode substrate according to any one of (1) to (5), wherein the electrode is a transparent conductive laminate having a sintered body of indium oxide and tin oxide as a main component.
(7) The electrode substrate according to any one of (1) to (5), wherein the electrode is a conductive polymer.

(8) The electrode substrate according to (2), wherein a transistor portion is provided on the electrode substrate so as to correspond to each pixel, and the transistor portion has a source contact, a drain contact, and a gate electrode.
(9) The electrode substrate according to (8), wherein the field effect transistor section has a semiconductor layer made of an organic material or a metal oxide as a main component.

By using the electrode substrate of the present invention, a flexible display or electronic paper having a paper-like texture can be obtained.

Next, the present invention will be described in detail with preferred embodiments. The electrode substrate of the present invention is one kind selected from paper, synthetic paper, paper or coated paper provided with a coating layer on synthetic paper, and a laminated sheet obtained by bonding paper and / or synthetic paper. It is characterized by.
According to the present invention, paper, synthetic paper, coated paper based on paper or synthetic paper, or a laminated sheet bonded with paper or synthetic paper is used as an electrode substrate, thereby having a paper-like texture. A flexible display or electronic paper can be provided. Examples of paper include paper containing cellulose pulp as a main component, such as high-quality paper (acidic paper, neutral paper), and medium-quality paper. Examples of coated paper include coated paper, art paper, and resin-laminated paper. Examples of the paper include a porous single layer stretched film or a porous multilayer stretched film mainly composed of a thermoplastic resin such as polyolefin or polyester, or a laminate of these. The thickness of the electrode substrate is not generally determined depending on the application, but is preferably 25 to 300 μm.

  In the present invention, the surface roughness of the electrode substrate on which the electrode is provided needs to have a surface roughness measured by JIS P 8151 of 5.0 μm or less, preferably 3.0 μm or less, More preferably, it is 2.0 μm or less. When the surface roughness of the electrode substrate exceeds 5.0 μm, it is necessary to form a conductive material sufficiently thicker than 5.0 μm in order to form electrodes, conductive wires, etc. on the surface of the substrate. However, it is difficult to use a dry process method such as a vacuum deposition method or a sputtering method. For example, when a thin wire such as the horizontal scanning wire 71 and the vertical scanning wire 72 shown in FIG. 7 is formed, there is a problem that the production yield is reduced because the wires are not conducted.

  Further, in the method of applying a coating solution in which a conductive material is dissolved or dispersed (that is, a wet process), a coating film thicker than 5.0 μm can be formed, but the coating film is too thick. When the electrode substrate is bent slightly, cracks are formed in the coating film of the conductive material, and disconnection easily occurs, and it is not suitable as an electrode substrate for a flexible display. Furthermore, if the coating layer of the conductive material is thick, the drying time becomes long and the cost increases, and the transparent conductive film after coating has problems such as coloring.

  In the present invention, the method of setting the surface roughness of the electrode substrate to 5.0 μm or less is not particularly limited. For example, a substrate having a large surface roughness is formed by a metal roll and a metal roll at 200 to 2500 kg / The surface roughness can be reduced by passing through the nip portion adjusted to a linear pressure of about cm. This method is a very effective means especially for a relatively low density material such as paper.

  Further, as a method for reducing the surface roughness, a synthetic resin layer can be provided on the surface on which the electrode is provided. Examples of the synthetic resin layer include, but are not limited to, cellophane, polyethylene, polypropylene, soft polyvinyl chloride, hard polyvinyl chloride, polyester, and acrylate polymer. Among these, for example, an acrylate polymer is applied to an electrode substrate in the form of a monomer, and a monomer such as polyethylene terephthalate (PET) is applied to the coated surface while applying an active energy ray (ultraviolet ray or electron beam). The method of polymerizing and solidifying, or the method of polymerizing and solidifying the monomer by irradiating the electron beam from the back surface of the electrode substrate while bringing the coated surface into contact with a cast drum having a specular gloss has high smoothness and the adhesion of the electrode. It is possible to form a coating layer of an acrylate polymer having good properties, which is preferably performed.

  In addition, in the process of studying paper-like displays, we measured the reflection of light when measuring with the position of the light source fixed between the substrate with the paper texture and the substrate with no paper texture. We studied earnestly the reflection angle dependence of the rate. In the case of a glass substrate or ordinary plastic film, the light reflected at the same angle is very strong with respect to the incident light from the light source, and the reflected light tends to become extremely weak if the angle of the receiver deviates even a little. It is in. On the other hand, in the case of paper or synthetic paper, the light that is reflected at the same angle as the incident light from the light source is the strongest, but the reflectivity is maintained even if the angle of the receiver is slightly deviated from the incident light angle. Turned out not to decrease so much.

The above measurement method will be described in detail. For example, in FIG. 1, there are a light source 2 and a light receiver 3 on the measurement surface side of the electrode substrate 1. The light source 2 is located at an angle x from the normal drawn on the substrate. x is usually measured in the range of 20 to 85 °. The light receiver 3 is on the opposite side of the light source across the normal. Here, the reflectance when the position of the light source is the angle x and the position of the light receiver is also the angle x with respect to the normal is R _X (%). The position of the light as it, and when tilted only base side 5 ° angle of the light receiver (i.e., the angle of the light receiver (x + 5) °) the reflectance R _{X + 5 (%)} of. Similarly, with the position of the light source as it is, the reflectance when the angle of the light receiver is inclined to the normal side by 5 ° (that is, the angle of the light receiver is (x-5) °) is R _X-5 (% ). The texture of paper or film is evaluated by determining and comparing the difference between R _X and R _{X + 5} and the difference between R _X and R _X-5 .

  FIG. 2 is a plot of the angle dependence of the reflectivity when the angle of the light receiver is changed. In this case, the position of the light source is fixed at an angle of 45 ° with respect to the substrate. Each of the four substrates has a peak at an angle of 45 °, but in the case of glass or transparent PET film, it shows a sharp peak at a reflection angle of 45 °, shifted by 5 ° from the reflection angle of 45 °, The reflectance value at 50 ° is less than 10%. On the other hand, in the case of paper or synthetic paper, the peak is also at the reflection angle of 45 °, but the reflectance values at 40 ° and 50 °, which are 5 ° off from the reflection angle of 45 °, remain at 50% or more. Yes.

  Although it is not clear why paper or synthetic paper shows the optical characteristics as described above, when light hits a substrate such as paper or synthetic paper, it not only reflects light but also scatters. This is thought to be due to the fact that light diffuses. It is considered that a so-called diffuse reflection phenomenon occurs. Such a diffuse reflection phenomenon often occurs when the structure of the substrate surface is not uniform but random. In particular, in the case of paper, it is considered that diffuse reflection tends to occur because pulp fibers are randomly arranged.

  The light reflection characteristics measured on the surface of the electrode substrate according to the present invention according to JIS Z 8741 are as measurement conditions where the light source and the light receiver are opposite to each other across the normal line at the measurement point on the electrode substrate. Yes, the angle with respect to the normal of the incident light from the light source is set to 45 °, the angle with respect to the normal at the measurement point of the receiver is R1 (%) at 45 °, and the reflectance at 50 °. When the reflectance at R2 (%) and 40 ° is R3 (%), the difference between R1 and R2 and the difference between R1 and R3 are preferably less than 50%, and a more preferable range is It is 0 to 30%, more preferably 0 to 15%. If the difference between R1 and R2 or the difference between R1 and R3 is 50% or more, the paper-like texture and visibility may be insufficient. The measurement surface of the electrode substrate preferably satisfies the above-mentioned reflection characteristics on both the surface on which the electrode is formed and the opposite surface depending on the usage pattern.

  By using the electrode substrate of the present invention, the contrast of the display device can be improved. When the display element is white, since the electrode substrate is also white and diffuse reflection as described above occurs, the reflection density value of the white portion is lowered. When the display element is black, the incident light used for measuring the reflection density is absorbed in black, so that only light on the very surface is detected. In other words, when displaying black, the original reflection density of the display element can be obtained without being affected by the electrode substrate. As a result, contrast is improved by using the electrode substrate of the present invention.

As the conductive material used to form the electrodes and the conductive lines of the electrode on the substrate or the like of the present invention, gold (Au), silver (Ag), a metal thin film type such as palladium _{(Pd), In 2 O 3} , SnO _2. Various types such as metal oxide thin film types such as ITO, zinc oxide (ZnO), and multilayer thin film types using metal / metal oxide such as titanium oxide (TiO ₂ ) / Ag / TiO ₂ can be used. Of these, ITO, which is a sintered body of indium oxide and tin oxide, is preferable from the viewpoint of transparency and conductivity. The thickness of the transparent conductive layer provided on the transparent polymer film is preferably 10 to 500 nm, more preferably 15 to 400 nm. If the thickness of the transparent conductive layer is 10 nm or less, uniform surface resistance may not be obtained. On the other hand, if the thickness is 500 nm or more, problems such as easy cracking may occur during the upper layer coating.

  Such a metal oxide thin film can be produced by various film forming methods such as a vacuum deposition method, a sputtering method, an ion plating method, a pulse laser deposition (PLD) method, or a CVD method. The PLD method is preferable for a display with a small research and development stage because the composition of the target can be directly reflected on the substrate. Moreover, the ion-grading method by the pressure gradient type discharge system which provides an intermediate electrode between a cathode and an anode has a high film forming speed, and is preferable for an actual production level.

  When the conductive material as described above is used, for example, by providing a simple matrix (passive matrix) electrode pattern, an electric field or a current can be supplied to each pixel. FIG. 3 shows an example in which a simple matrix type electrode pattern is provided. An electrode 11 is patterned in the lateral direction on the electrode substrate 1 of the present invention. As a patterning method, when the metal oxide thin film is formed, the electrode substrate is covered with a mask, or the electrode is once formed on the entire surface of the substrate, and then conductive using a photoresist material or the like. A method of etching the material is exemplified, and the method is not particularly limited. In general, a display device including a front plate 12 on which electrodes are arranged is preferably used.

  As shown in FIG. 3, it is preferable that the front plate 12 on the viewer 4 side is normally transparent. When the transparency of the front plate 12 on the viewer side is insufficient, the switching behavior of the display element may not be observed and may not function sufficiently as a display. Examples of the front plate 12 include polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyamide, aromatic polyamide, polyamideimide, polyetherimide, polyethersulfone, polysulfone, polyetheretherketone, polyarylate, polycarbonate, and polyphenylene sulfide. , Polyphenylene oxide, polyparabanic acid and the like. Of these, polyesters such as polyethylene terephthalate and polyethylene naphthalate, polyethersulfone, polycarbonate, and polyarylate are preferably used from the viewpoint of heat resistance and transparency. The thickness of the transparent polymer film is preferably 25 to 200 μm.

  For example, in the case of a display that does not need to support moving images, such as electronic paper, a conductive polymer having a relatively high resistance value can be used instead of the conductive material used above. Examples of the conductive polymer include polyacetylene, poly (paraphenylene), polypyrrole, polythiophene, polyaniline, poly (paraphenylene vinylene), and the like. Among these, a polythiophene-based transparent conductive polymer is preferable from the viewpoints of transparency and conductivity. Examples of the polythiophene-based transparent conductive polymer include 3,4-polyethylenedioxythiophene, poly (3-hexyl) thiophene, poly (3-octyl) thiophene, poly (3-dodecyl) thiophene, and poly (3-octadecyl) thiophene And poly (3-icosyl) thiophene.

  Among these, 3,4-polyethylenedioxythiophene is preferably used in terms of transparency and conductivity. The thickness of the polythiophene-based transparent conductive polymer layer is preferably 0.03 to 5 μm, and more preferably 0.05 to 3 μm. Such a layer can be formed by a roll coater, a gravure coater, a bar coater or the like. If the thickness of the polythiophene-based transparent conductive polymer layer is less than 0.03 μm, sufficient bending resistance may not be obtained. On the other hand, if it exceeds 5 μm, the coating amount increases, the drying time becomes longer, the cost increases, and the transparent conductive film after coating may be colored.

  As shown in FIG. 4, a so-called In-Plane electrode in which two electrodes are provided on one electrode substrate can also be used. This is a system in which an electrode 41 for supplying electricity and an electrode 42 connected to ground are provided on the electrode substrate 1 of the present invention. When electricity is supplied to the electrode 41, the electricity is applied to the electrode 42 connected to the ground. That is, the direction in which electricity is applied is a direction parallel to the electrode substrate 1. In this case, it is not necessary to provide an electrode on the viewer 4 side, and a transparent plastic film or a glass substrate may be used when flexibility is not required. As long as the display element itself is sufficiently sealed, there may be nothing on the viewer 4 side.

  The electrode substrate of the present invention can also be employed in an active matrix system in which a field effect transistor portion is arranged for each pixel. Most modern flat panel displays employ an active matrix system. 5 and 6 are schematic views of the field effect transistor section. FIG. 5 shows a structure called a bottom contact system, and FIG. 6 shows a structure called a top contact system. A gate electrode 53 is provided as a conductive portion on the electrode substrate, and a gate insulating film 52 is provided thereon. A semiconductor layer 51 is provided so as to be in contact with the gate insulating film, and further, a source electrode 54 and a drain electrode 55 are provided as conductive materials.

  FIG. 7 shows an example in which a field effect transistor portion is arranged on the electrode substrate of the present invention. The electrode substrate 1 of the present invention is first provided with a horizontal scanning electric wire 71 called a gate line. A gate electrode 53 is arranged for each pixel in the horizontal scanning electric wire 71. A vertical scanning electric wire 72 called a data line is provided thereon. An insulating film is provided at the intersection so that the horizontal scanning wire 71 and the vertical scanning wire 72 do not contact each other. A gate insulating film 52 is provided on the gate electrode, and a semiconductor layer 51 is provided thereon. In the vertical scanning electric wire 72, the source electrode 54 is disposed for each pixel, and the source electrode 54 is disposed on the semiconductor layer 51. Further, there is a pixel electrode 73 that is in contact with the display element and directly transmits electricity, and the drain electrode 55 is in contact with the semiconductor layer 51 and the pixel electrode 73. Electricity applied to the display element from the pixel electrode 73 flows to the front plate 12 connected to the ground.

  As a semiconductor material used for the semiconductor layer 51, a known material can be used, and is not particularly limited. However, a material that can be formed at a heat resistant temperature of the electrode substrate of the present invention, that is, 300 ° C. or less, is preferably used. It is done. Examples of semiconductor materials that can be formed at 300 ° C. or lower include organic semiconductor materials such as pentacene, phthalocyanine metal complexes, polythiophene, poly (3-hexylthiophene), polypyrrole, polyacetylene, polythiophene vinylene, and polyphenylene hysenylene. And poly (9,9′-dioctylfluorocene-co-bithiophene), and pentacene is particularly preferably used because of its high mobility.

  In addition to dry processes such as vacuum deposition, sputtering, ion plating, pulsed laser deposition (PLD), or CVD, semiconductor materials are soluble in various solvents. If so, it can also be formed by a wet process such as a printing method. As the printing method, for example, an inkjet method, a gravure method, an intaglio method, a flexo method, a screen method, or the like can be used.

  Further, various metal oxides can also be used as the semiconductor material. As the metal oxide, a material exhibiting semiconductor characteristics is used. For example, indium oxide, gallium oxide, zinc oxide, or a mixed In-Ga-Zn-O-based oxide is used. In—Ga—Zn—O-based oxides having the best performance are used.

  When a metal oxide is used as a semiconductor material, a vacuum deposition method, a sputtering method, an ion plating method, a pulse laser deposition (PLD) method, a CVD method, or the like can be used as a film forming method. Among these, the PLD method is more preferably used because the composition of the target can be directly reflected on the substrate. However, when a material such as a metal oxide is used as a semiconductor material, a method for forming a film by a wet process such as a printing method has not been developed.

  Hydrogenated amorphous silicon or low-temperature polysilicon can be used as the semiconductor material, but in this case, it is impossible to form a film directly on the electrode substrate of the present invention because of heat resistance. In this case, a process is used in which hydrogenated amorphous silicon or low-temperature polysilicon is formed on a separately prepared glass substrate and then transferred to the electrode substrate of the present invention by a transfer method.

Examples of the gate insulating film 52 include inorganic dielectric materials such as SiO ₂ , Al ₂ O ₃ , Si ₃ N ₄ , TiO ₂ , and Y ₂ O ₃ , polyimide, mylar, polyvinylidene fluoride, and polymethyl methacrylate. Examples include organic polymer materials.

As the material of the gate electrode 53, the source electrode 54, the drain electrode 55, the horizontal scanning electric wire 71, and the vertical scanning electric wire 72, various conductive materials can be used. For example, metal thin film types such as gold (Au), silver (Ag), palladium (Pd), metal oxide thin film types such as In ₂ O ₃ , SnO ₂ , ITO, and zinc oxide (ZnO), and titanium oxide (TiO 2) ₂ ) Various types such as a multilayer thin film type of metal / metal oxide such as / Ag / TiO ₂ can be used. Of these, ITO is preferable from the viewpoint of transparency and conductivity.

  When the active matrix method is employed, the front plate 12 does not need to be patterned as shown in FIG. 3, and may be a solid electrode.

  Examples of the display element used for the electrode substrate of the present invention include twisted nematic (TN) liquid crystal, super twisted nematic (STN) liquid crystal, polymer dispersed liquid crystal in which these liquid crystals are dispersed in a polymer matrix, and organic EL. A display element usually used for a flat panel display, such as an element, an inorganic EL element, or a plasma display element in which a rare gas is sealed, can be used.

The electrode substrate of the present invention can be used for the flexible flat panel display as described above. However, by using it for a display called “electronic paper”, the characteristics of the electrode substrate of the present invention can be maximized. And a more paper-like display can be provided. As a method of electronic paper, for example, a microcapsule obtained by dispersing electrophoretic particles in an insulating liquid (see, for example, Patent Document 1), a so-called half surface is white and the other half surface is black. A method of displaying black and white by rotating dichroic particles (see, for example, Patent Document 2), in which a hollow cylindrical fiber encloses a cylindrical element in which one half is white and the other half is black ( For example, see JP-A-2002-202536), a method in which charged white and black particles fly in the air by an electric field, a memory type liquid crystal using cholesteric liquid crystal, a method using an electrochromic material, and a leuco dye. The method used (for example, refer to Japanese Patent Application Laid-Open No. 2004-309984) and the like are exemplified, and the method is not particularly limited.
As an example of a preferred embodiment of the present application, FIGS. 8 and 9 are schematic views of a display element and a display device in which the display element is arranged.

  EXAMPLES Hereinafter, although an Example is given and this invention is demonstrated in detail, this invention is not limited to these Examples. Unless otherwise specified, “%” and “parts” in the examples are “% by mass” and “parts by mass”.

<Manufacture of support (electrode substrate)>
(1) Support A
Coniferous bleached kraft pulp (NBKP) beaten to a freeness of 250 mL (JIS P 8121) and hardwood bleached kraft pulp (LBKP) beaten to a freeness of 250 mL were mixed at a mass ratio of 2: 8. A pulp slurry having a concentration of 0.5% was prepared. In this pulp slurry, cationized starch 2.0%, alkyl ketene dimer 0.4%, anionized polyacrylamide resin 0.1% and polyamide polyamine epichlorohydrin resin 0.7% are added to the pulp dry weight. The mixture was sufficiently stirred and dispersed.
The pulp slurry having the above composition was made with a long net machine, and passed through a dryer, a size press, and a machine calendar to produce a base paper having a basis weight of 180 g / m ² and a density of 1.0 g / cm ³ . The size press liquid used in the size press step was prepared by mixing carboxyl-modified polyvinyl alcohol and sodium chloride at a mass ratio of 2: 1, adding this to water and dissolving it by heating to prepare a concentration of 5%. This size press solution was applied to both sides of the paper in a total of 25 mL / m ² to obtain a support A.

(2) Support B
The support A was passed through a nip formed by a metal roll and a metal roll under the conditions of a linear pressure of 1000 kg / cm and a metal roll temperature of 170 ° C. to obtain a support B.

(3) Support C
After the corona discharge treatment was performed on the felt surface of the base paper of the support A, the following polyolefin resin composition was mixed and dispersed with a Banbury mixer, and this dispersion was applied to the felt surface side of the support A with a coating amount of 25 g / m ² . Thus, it apply | coated with the melt extruder (melting temperature of 320 degreeC) which has a T type | mold die, it solidified by cooling with the mirror surface cooling roll, and the support body C which coat | covered polyolefin resin was obtained.

(Polyolefin resin composition)
35 parts long chain low density polyethylene resin (density 0.926 g / cm ³ , melt index 20 g / 10 min), 50 parts low density polyethylene resin (density 0.919 g / cm ³ , melt index 2 g / 10 min), anatase Type titanium dioxide (trade name: A-220, manufactured by Ishihara Sangyo Co., Ltd.) 15 parts, zinc stearate 0.1 part, antioxidant (trade name: Irganox 1010, manufactured by Ciba Geigy) 0.03 parts, ultramarine (trade name) : Aoguchi Ultramarine NO.2000, manufactured by Daiichi Kasei Co., Ltd.) 0.09 part and fluorescent whitening agent (trade name: UVITEX OB, manufactured by Ciba Geigy Co., Ltd.) 0.3 part were mixed to obtain a polyolefin resin composition.

(4) Support D
After coating the following acrylate monomer-containing coating solution on one surface of the support A using a Mayer bar so that the coating amount after curing is 15 g / m ² , this coating layer is subjected to chromium plating on the surface. The double-side coated paper was bonded to the surface of the molded substrate (trade name: King, ferrotype plate, stainless steel, hard chrome plating finish, manufactured by Asanuma Shokai), and acceleration voltage was applied from the back side of the support A The support layer D was obtained by irradiating an electron beam at 200 kV and an absorbed dose of 4 Mrad to cure the coating layer to form an acrylate resin layer.

(Acrylate monomer-containing coating solution)
40 parts of urethane acrylate oligomer (trade name: Beamset 550B, manufactured by Arakawa Chemical Industries), 60 parts of hydroxypivalic acid neopentyl glycol ester diacrylate (trade name: MANDA, manufactured by Nippon Kayaku Co., Ltd., bifunctional acrylate monomer) are mixed, An acrylate monomer-containing coating solution was prepared.

(5) Support body E
As the support E, polypropylene resin-based synthetic paper (trade name: YUPO FPG-110, manufactured by YUPO Corporation, thickness 110 μm) was used.

(6) Support F
In the production of the support D, a support F was obtained in the same manner as the support D except that the support E was used instead of the support A.

(7) Support G
As the support G, a polyethylene terephthalate film (trade name: T60- # 188, manufactured by Toray) having a thickness of 188 μm was used.

(8) Support H
In the production of the support D, a support H was obtained in the same manner as the support D except that the support G was used instead of the support A.

Evaluation of the support The following evaluation was performed on the support prepared by the above method, and the results are shown in Table 1.
〔Surface roughness〕
The surface roughness of the surface of the prepared support on the side where the electrode is provided was measured based on the method of JIS P 8151. The measuring device for surface roughness was a Parker Print Surf Tester (Messmer), and the pressure between the measuring head and the packing was 0.5 MPa.

(Optical characteristics)
The light reflection characteristics of the produced support were measured using a goniophotometer (trade name: GP-1R, manufactured by Murakami Color Research Laboratory). The angle between the sample and the light source was fixed at 45 °, and the reflectance at three points of the light receiver angles of 40 °, 45 °, and 50 ° was measured.

＜前面板＞
支持体Ｇ上に、ＳｎＯ_２を５重量％含むＩＴＯを使用し、小型高周波スパッタリング装置（商品名：ＲＦＳ−２００、アルバック社製）を用いてスパッタリング法により透明導電膜を１５ｎｍの厚さに形成し、前面板とした。前面板のＩＴＯ蒸着面には、アースに接続したリード線をはんだ付けした。

<Front plate>
Using ITO containing 5% by weight of SnO ₂ on the support G, a transparent conductive film is formed to a thickness of 15 nm by a sputtering method using a small high-frequency sputtering apparatus (trade name: RFS-200, manufactured by ULVAC). The front plate was used. A lead wire connected to the ground was soldered to the ITO deposition surface of the front plate.

<Display element>
2.5 parts of rosin ester (trade name: Neotol 125H, manufactured by Harima Chemical Co., Ltd.) was mixed with 100 parts of Isopar G (Exxon) as a dispersion medium and stirred for 24 hours. Titanium oxide particles (trade name: R-980, manufactured by Ishihara Sangyo Co., Ltd.) and carbon black particles (trade name: MICROJET, manufactured by Orient Chemical Industry Co., Ltd.) are respectively added to this dispersion medium and stirred. A dispersion was obtained by mixing and dispersing with an apparatus. On the other hand, in another flask, 50 parts of a 5% aqueous solution of an ethylene-maleic acid alternating copolymer (Aldrich reagent), 2.5 parts of urea (reagent manufactured by Kanto Chemical), resorcinol (reagent manufactured by Kanto Chemical) 0.25 And 25 parts of pure water were mixed, and 12.5 wt% aqueous sodium hydroxide solution was added to adjust the pH of the mixed solution to 3.5.

  A homogenizer (trade name: Ultra Turrax DIXI Midi T18) was set in the flask, and 25 parts of the above dispersion was added while stirring at 6,000 rpm. After the dispersion state was stabilized by addition, 6.25 parts of a 35% formaldehyde aqueous solution (Kanto Chemical Co., Ltd.) was added, and the mixture was reacted at 55 ° C. for about 2 hours to perform microencapsulation. After completion of the reaction, the produced microcapsules were separated by filtration, washed repeatedly with pure water, and air-dried overnight. The average particle size of the resulting microcapsules was about 50 μm under digital microscope observation. To 10 parts of the dried microcapsules, 10 parts of a 10% aqueous solution of polyvinyl alcohol (trade name: PVA145, manufactured by Kuraray Co., Ltd.) is added as a binder component. And dried at 60 ° C. for 1 hour.

Example 1
A support B is used as an electrode substrate, and an ITO vapor deposition surface is formed on one side of the support in the same manner as the production of the front plate. A direct current power supply device (pulse generator (trade name: A lead wire connected to an amplifier (product name: A800, manufactured by Toyo Technica) connected to Generator 8026 (manufactured by Toyo Technica) was soldered. Apply the epoxy adhesive very thinly on the display element side of the display element-coated front plate, and paste it so that the display element side of the front plate and the ITO deposition surface of the support B are in contact with each other. A display device was obtained. The thickness of the display element layer sandwiched between the front plate and the support B was 60 μm.

Example 2
A display device was produced in the same manner as in Example 1 except that the support C was used instead of the support B as the electrode substrate, and the ITO vapor deposition surface was formed on the polyolefin resin coating layer surface of the support.

Example 3
A display device was produced in the same manner as in Example 1 except that the support D was used instead of the support B as the electrode substrate, and an ITO vapor deposition surface was formed on the surface of the acrylate resin layer of the support.

Example 4
In Example 1, a display device was obtained in the same manner as in Example 1 except that the support E was used instead of the support B.

Example 5
In Example 3, a display device was obtained in the same manner as Example 1 except that the support F was used instead of the support D.

Example 6
The support D was used as an electrode substrate, and an active matrix type electrode as shown in FIG. 7 was produced on the surface of the acrylate resin layer of the support. The procedure was as follows.
First, in order to form the gate electrode 53, the horizontal scanning wire 71, and the pixel electrode 73, the portions other than the gate electrode 53, the horizontal scanning wire 71, and the pixel electrode 73 are covered with a metal mask, and ITO containing 5% by weight of SnO ₂ is used. Using this, a transparent conductive film was formed to a thickness of 15 nm by the same sputtering method as in the production of the front plate. Next, an insulating film was formed by sputtering using Al ₂ O ₃ as an insulating material at a portion where the gate insulating film 52 intersects with the horizontal scanning wire 71 and the vertical scanning wire 72. Furthermore, pentacene (Tokyo Kasei Reagent) was used as a semiconductor material, and the semiconductor layer 51 was formed by a vapor deposition method using a vacuum vapor deposition apparatus (trade name: ELORA-100, manufactured by ULVAC). At this time, the temperature of the support C was controlled so as to be constant at 27 ° C.

Finally, in order to form the source electrode 54, the drain electrode 55, and the vertical scanning electric wire 72, the portions other than the gate electrode 53, the horizontal scanning electric wire 71, and the pixel electrode 73 are covered with a metal mask, and then gold (Au) is used. The conductive layer was formed by the same sputtering method as that for manufacturing the front plate. The width between the source and the drain was 1.5 mm, the length was 70 μm, and the mobility of the formed semiconductor layer 51 was 0.06 cm ² / V · sec. On the other hand, apply a very thin epoxy adhesive to the display element side of the front plate coated with the display element, and attach the front plate so that the display element side of the front plate and the electrode surface side of the support D are in contact with each other. A display device was obtained. The thickness of the display element layer sandwiched between the front plate and the support D was 60 μm.

Example 7
In Example 6, a display device was obtained in the same manner as in Example 6 except that a semiconductor layer was formed by a sputtering method using In—Ga—Zn—O-based oxide instead of pentacene as the semiconductor material. . Note that the mobility of the semiconductor layer was 1.0 cm ² / V · sec.

Comparative Example 1
A display device was obtained in the same manner as in Example 1 except that the support A was used instead of the support B in Example 1.

Comparative Example 2
A display device was obtained in the same manner as in Example 1 except that the support G was used instead of the support B in Example 1.

Comparative Example 3
In Example 3, a display device was obtained in the same manner as Example 3 except that the support H was used instead of the support D.

Evaluation of Display Device The display device manufactured by the above method was evaluated as follows, and the evaluation results are shown in Table 2.
[Operation check]
Using the manufactured display device, the operation state due to the electric field was visually observed.
The case where it operates without a problem was marked with ◯, and the case where it did not work was marked with ×.

[Evaluation of paper texture]
The appearance of the entire display device was sensoryly evaluated visually by visual inspection for similarity to commercially available paper.
The display device as a whole has a paper texture, and the display device does not have a paper texture.

[Contrast evaluation]
In Examples 1 to 5 and Comparative Examples 1 to 3, when a voltage of 100 V is applied between the front plate and the support (electrode substrate) and a positive voltage is applied to the front plate, The reflection density value when a negative voltage was applied to the face plate was measured with a Macbeth densitometer (trade name: RD-914 type, manufactured by Macbeth Co.), and the ratio of both reflection density values was taken as contrast. For Examples 6 and 7, when a voltage is applied to the horizontal scanning wire 71 and the voltage applied to the vertical scanning wire 72 is plus, hour, and minus, the respective reflection density values are measured with a Macbeth densitometer. The ratio of values was taken as contrast.

表２から明らかなように、本発明の請求項の範囲内である実施例１〜７の電極用基板は、紙の質感を持つ表示装置を提供することができる。実施例１〜５のような、単純マトリックス方式にのみならず、実施例６、７のようにアクティブマトリックス方式を用いることもできる。さらに、表示素子のコントラストも改善された。
一方、比較例１は、支持体Ａの表面粗さが大きいため、導電性材料を均一に製膜することができず、動作させることができなかった。また、比較例２と３は、透明な電極用基板を用いているために、紙のような質感は得られない。また、電極用基板が透明であるためか、表示素子が白を表示した時の反射濃度値が本発明の実施例と比較して高くなり、コントラストが低下している。

As is apparent from Table 2, the electrode substrates of Examples 1 to 7 within the scope of the claims of the present invention can provide a display device having a paper texture. Not only the simple matrix method as in the first to fifth embodiments but also the active matrix method as in the sixth and seventh embodiments can be used. Furthermore, the contrast of the display element was also improved.
On the other hand, in Comparative Example 1, since the surface roughness of the support A was large, the conductive material could not be uniformly formed and could not be operated. In Comparative Examples 2 and 3, since a transparent electrode substrate is used, a paper-like texture cannot be obtained. Also, because the electrode substrate is transparent, the reflection density value when the display element displays white is higher than that of the example of the present invention, and the contrast is lowered.

  According to the present invention, an electrode substrate capable of realizing a flat panel display having a paper-like texture can be provided. Therefore, the electrode substrate of the present invention has extremely high practical value.

It is a conceptual diagram of the apparatus which measures the optical characteristic used for this invention. It is an example of the graph which plotted the reflectance with respect to the angle of a light receiver. It is a conceptual diagram which shows an example of the simple matrix system using the board | substrate for electrodes of this invention. It is a conceptual diagram which shows an example of the In-Plane electrode using the electrode substrate of this invention. It is sectional drawing which shows an example of the bottom contact system of the active matrix system used for this invention. It is sectional drawing which shows an example of the top contact system of an active matrix system used for this invention. It is a conceptual diagram which shows an example of the active matrix system used for this invention. It is sectional drawing which shows an example of the microcapsule type display element used for this invention. It is a conceptual diagram which shows an example of the display apparatus which has arrange | positioned the display element to the board | substrate for electrodes of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate for electrodes 2 Light source 3 Light receiver 4 Observer 11 Electrode 12 Front plate 41 Electrode for supplying electricity 42 Electrode connected to ground 51 Semiconductor layer 52 Gate insulating film 53 Gate electrode 54 Source electrode 55 Drain electrode 71 Horizontal scanning Electric wire 72 Vertical scanning electric wire 73 Pixel electrode 81 Microcapsule 82 Carbo black particle 83 Titanium oxide particle 84 Dispersion medium 85 Microcapsule wall agent

Claims (9)

  In the electrode substrate which has an electrode on the surface and the display element is disposed thereon and is used in the display device, the electrode substrate is provided with a coating layer on paper, synthetic paper, paper or synthetic paper Surface roughness based on JIS P 8151 on the side where the electrode of the electrode substrate is provided, which is one type selected from coated paper and a laminated sheet bonded with paper and / or synthetic paper An electrode substrate characterized by the above.   The electrode substrate according to claim 1, wherein the electrode substrate is used in a display device including a transparent front plate on which electrodes are further arranged on the display element.   The electrodes for supplying electricity to the electrode substrate and the electrodes connected to the ground are alternately arranged so that the direction of the supplied electricity is parallel to the plane direction of the electrode substrate. Item 2. The electrode substrate according to Item 1.   The light reflection characteristic measured according to JIS Z 8741 on the surface of the electrode substrate is as a measurement condition that the light source and the light receiver are opposite to each other across the normal line at the measurement point on the electrode substrate, The angle with respect to the normal line of the incident light from the light source is set to 45 °, the angle with respect to the normal line at the measurement point of the receiver is R1 (%) at 45 °, and the reflectance at 50 ° is R2 ( %) And when the reflectance at 40 ° is R3 (%), the difference between R1 and R2 and the difference between R1 and R3 is less than 50%. The electrode substrate as described.   The electrode substrate according to claim 1, wherein the electrode substrate has a synthetic resin layer on the electrode side.   The electrode substrate according to claim 1, wherein the electrode is a transparent conductive laminate including a sintered body of indium oxide and tin oxide as a main component.   The electrode substrate according to claim 1, wherein the electrode is a conductive polymer.   The electrode substrate according to claim 2, wherein a transistor portion is provided on the electrode substrate so as to correspond to each pixel, and the transistor portion has a source contact, a drain contact, and a gate electrode. The electrode substrate according to claim 8, wherein the field effect transistor portion includes a semiconductor layer made of an organic material or a metal oxide as a main component.

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