JP2006066366A - Method for manufacturing display panel and apparatus for coating viscosity and moisture-absorbing member - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To properly coat on an organic EL panel, a viscosity and moisture-absorbing member for suppressing the effect of moisture and oxygen, and for maintaining light-emitting characteristics. <P>SOLUTION: A method for manufacturing a display panel manufactures a display panel having a first substrate, a second substrate, and a display element formed in a sealed space between the first and the second substrates, coats the member onto the first substrate, sprays gas against the member coated to the first substrate so as to make the thickness of the member small and seals the first and the second substrates with an adhesive so that the member is disposed inside the space. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a display panel manufacturing method and a viscous moisture-absorbing member coating apparatus, and more particularly to application of a viscous moisture-absorbing member on a substrate of a display panel.

  An organic EL (Electro Luminescence) element has a laminate structure in which an organic EL layer containing an organic light emitting compound is sandwiched between an anode and a cathode. When a voltage is applied between the anode and the cathode, holes from the anode and electrons from the cathode are injected into the organic EL layer to recombine, and the organic light-emitting property contained in the organic EL layer is generated by the energy generated at that time. The molecule of the compound is excited. A light emission phenomenon occurs in the process in which the excited molecules are deactivated to the ground state. An organic EL element is a self-luminous element utilizing this light emission phenomenon.

  The organic EL layer includes at least an organic layer called a light-emitting layer that emits light by recombination of holes and electrons. If necessary, an organic layer called a hole transport layer that is easy to inject holes and hardly move electrons. The layer has a single layer structure or a multilayer structure including one or both of an organic layer called an electron transport layer that is easy to inject electrons and hardly move holes.

  In general, an organic EL panel is formed by sequentially laminating a transparent electrode serving as an anode with ITO (Indium Tin Oxide), an organic EL layer, and an electrode serving as a cathode with aluminum or the like on a glass substrate. The organic EL element is formed, and a concave counter substrate made of glass or the like covering the laminated body is hermetically disposed on the substrate via an ultraviolet curable adhesive.

  One of the major problems of this organic EL panel is to improve the lifetime of the light emitting layer. One of the causes for shortening the lifetime is the occurrence of a non-light emitting portion called a dark frame. The non-light emitting portion grows with the lighting elapsed time, and the non-light emitting area gradually increases, and the light emission luminance of the light emitting portion decreases. The main cause of the generation of the non-light-emitting portion is a reaction between the organic EL layer constituting the organic EL element and moisture or oxygen in the sealed container. As a result, it is known that non-light emitting portions are generated and grown.

  Therefore, in the conventional organic EL panel, the lifetime of the organic EL element is improved by disposing a moisture absorbing member in an airtight space obtained by the substrate on which the organic EL element is disposed and the counter substrate. As this moisture absorbing member, an inorganic desiccant is known (see Patent Document 1).

  In addition, an organic metal compound that is highly reactive with moisture is formed into a film, and a water capturing layer is formed in an airtight space obtained between the substrate on which the organic EL element is disposed and the counter substrate, and an effect is obtained by utilizing a chemical reaction. In particular, a method for capturing moisture is known (see Patent Document 2).

Furthermore, a moisture absorbing member having a viscosity obtained by mixing a solid adsorbent in an inert liquid made of, for example, fluorine-based oil at a predetermined ratio is applied to the surface facing the laminate of the counter substrate, and the airtight space A structure that absorbs moisture is known (see Patent Document 3).
Japanese Patent Laid-Open No. 9-148066 JP 2002-33187 A JP 2003-163076 A

  As disclosed in Patent Document 3, an organic EL panel using a viscous moisture-absorbing member is manufactured by applying a moisture-absorbing member to a surface of the counter substrate facing the laminate. In this application step, the moisture absorbing member is applied at a predetermined position using an application device such as a dispenser. The viscous hygroscopic member can be disposed at a desired position by a dispenser, and is also an excellent hygroscopic member from the viewpoint of cost.

  However, when the hygroscopic member is applied, when the dispenser needle finishes discharging the hygroscopic member and leaves the hygroscopic member, a phenomenon occurs in which the hygroscopic member pulls a thread or leaves a horn due to the viscosity of the hygroscopic member. Due to the stringing of the hygroscopic member, the hygroscopic member enters the bonding portion between the substrate on which the organic EL element is laminated and the counter substrate on which the hygroscopic member is disposed, and there is a problem that a problem occurs in bonding. In addition, the horn of the hygroscopic member comes into contact with the organic EL element, thereby damaging the electrode, causing a phenomenon that the light emitting portion of the organic EL element does not partially emit light, and in some cases, a short circuit between the electrodes occurs. was there.

  In order to solve these problems, there is a method of stopping the discharge of the hygroscopic member from the needle before the end point of movement of the needle, and raising the needle after moving the needle to the end point of movement without discharging the hygroscopic member. It has been proposed (see Patent Document 3). Accordingly, it is possible to prevent the generation of horns of the hygroscopic member and prevent the stringed hygroscopic member from entering the bonded portion between the substrate on which the organic EL element is laminated and the counter substrate.

  However, in this method, the hygroscopic member cannot be applied between the application end point position (discharging stop position) and the needle movement end point position. For this reason, the application amount of the hygroscopic member is insufficient, and the hygroscopic performance necessary for improving the life of the organic EL element may not be satisfied. In particular, in the case of a small organic EL panel such as a mobile phone display, the application amount of the moisture absorbing member is insufficient due to the insufficient distance to apply the moisture absorbing member, and a predetermined amount cannot be applied, and the desired moisture absorption performance is obtained. There wasn't.

  The present invention has been made against the background described above, and a first object of the present invention is to prevent the occurrence of non-light-emitting portions or short-circuiting between electrodes due to adhesion of a viscous hygroscopic member. It is. The second object of the present invention is to increase the amount of the viscous moisture absorbing member applied to the substrate of the display panel.

  A method for manufacturing a display panel according to a first aspect of the present invention is formed in a sealed space between a first substrate, a second substrate, and the first substrate and the second substrate. A display panel having a display element, wherein a viscous moisture absorbing member is applied on the second substrate, and a gas is blown onto the viscous moisture absorbing member applied on the second substrate. The thickness of the moisture absorbing member is reduced, and the first substrate and the second substrate are sealed with an adhesive so that the viscous moisture absorbing member is disposed in the sealed space. Thereby, the thickness of the viscous hygroscopic member can be controlled effectively.

  In the display panel manufacturing method according to the second aspect of the present invention, the display element is formed on the first substrate, and the viscous moisture absorbing member faces the display element of the second substrate. It can be applied on the surface. Thereby, contact between the viscous hygroscopic member and the display element can be prevented.

  The display panel manufacturing method according to the third aspect of the present invention is applied to the second substrate such that the viscous moisture absorbing member has a thickness that does not contact the display element formed on the first substrate. It is preferable to blow a gas against the formed viscous hygroscopic member. Thereby, contact between the viscous hygroscopic member and the display element can be prevented.

  In the display panel manufacturing method according to the fourth aspect of the present invention, it is preferable that gas is blown so that the thickness of the application terminal portion of the viscous moisture absorbing member is reduced. Thereby, in the case of applying by a dispenser or the like, it is possible to eliminate an undesirable shape such as a protrusion at the application end portion.

  A manufacturing method of a display panel according to a fifth aspect of the present invention includes a first substrate, a second substrate, and a display element formed between the first substrate and the second substrate. A method for manufacturing a display panel, comprising: applying a viscous hygroscopic member on the second substrate; and blowing a gas onto the viscous hygroscopic member applied on the second substrate to deform the shape of the viscous hygroscopic member Then, the first substrate and the second substrate are fixed by an adhesive. Thereby, the shape of the viscous hygroscopic member can be controlled effectively.

  In the display panel manufacturing method according to the sixth aspect of the present invention, it is preferable that the application area of the viscous hygroscopic member is increased by blowing gas onto the viscous hygroscopic member. Thereby, the application amount of the viscous hygroscopic member can be increased.

  An application device for a viscous hygroscopic member according to a seventh aspect of the present invention includes: a stage on which a substrate is placed; a dispenser that moves relative to the stage and applies the viscous hygroscopic member to the substrate on the stage; And a nozzle that blows gas onto the viscous hygroscopic member coated on the substrate. Thereby, the shape of the viscous hygroscopic member can be controlled effectively.

  In the viscous moisture-absorbing member coating apparatus according to the eighth aspect of the present invention, the nozzle preferably ejects gas toward the discharge port of the dispenser. Thereby, it is possible to effectively eliminate an undesirable shape such as a protrusion at the application end portion of the viscous moisture absorbing member.

  In the display panel manufacturing method according to the ninth aspect of the present invention, a display element is formed on a first substrate, and a second substrate for sealing the display element is fixed to the first substrate. A method of manufacturing a display panel, wherein a viscous moisture absorbing member is linearly applied to the surface of the second substrate facing the display element, and a gas is sprayed onto an end of the viscous moisture absorbing member after application. The thickness is not more than a predetermined thickness. Thereby, in the case of applying by a dispenser or the like, it is possible to eliminate an undesirable shape such as a protrusion at the application end portion. Further, contact between the viscous moisture absorbing member and the display element can be prevented.

  In the manufacturing method of the display panel according to the tenth aspect of the present invention, the viscous moisture absorbing member is arranged so that the distance applied linearly when applying the viscous moisture absorbing member is 5 to 80 mm. Thereby, it is possible to arrange a viscous moisture absorbing member in an amount necessary for suppressing the deterioration of display characteristics of the display panel.

Method of manufacturing a display panel according to an eleventh aspect of the present invention, in a surface parallel to the inner surface of the second substrate, is intended for applying the viscous hygroscopic member to occupy an area of 100 to 2000 mm ^2. This makes it possible to dispose a viscous moisture-absorbing member necessary for suppressing deterioration of display characteristics of the display panel.

In the sealing substrate according to the twelfth aspect of the present invention, a recess having a depth of 0.55 to 0.35 mm is formed on one surface of a transparent substrate having a thickness of 1.1 to 0.7 mm, and a viscous member is formed in the recess. Is placed without contacting the inner surface of the recess, and the viscous moisture absorbing member is disposed so that the surface area of the viscous moisture absorbing member parallel to the inner surface of the transparent substrate is 100 to 2000 mm ^2. The By forming a display panel using this sealing substrate, display characteristics can be prevented from deteriorating.

  According to the present invention, it is possible to appropriately apply a viscous moisture absorbing member necessary for maintaining display characteristics to a substrate.

  Embodiments to which the present invention can be applied will be described below. The following description explains the embodiment of the present invention, and the present invention is not limited to the following embodiment.

  The configuration of the organic EL panel according to the present invention will be described with reference to FIG. FIG. 1 is a schematic cross-sectional view showing a part of the configuration of the organic EL panel 100. FIG. 1 schematically shows the configuration of the organic EL panel, and does not reflect the detailed configuration of the actual organic EL panel.

  The organic EL panel 100 has a configuration in which an organic EL element 110 is formed in an airtight space obtained by a substrate 101 made of glass or the like and a counter substrate 106. The substrate 101 and the counter substrate 106 are fixed with an adhesive 108. The organic EL element 110 formed on the substrate 101 includes an anode 102, an insulating layer 103, an organic EL layer 104, and a cathode 105. When a voltage is applied between the anode 102 and the cathode 105, holes are injected from the anode and electrons are injected from the cathode into the organic EL layer 104 to recombine, and energy generated at that time causes recombination in the organic EL layer 104. The molecule of the organic light emitting compound is excited. The excited molecules are deactivated to the ground state, and the organic EL layer 104 emits light in the process.

  As shown in FIG. 1, an anode 102 is formed on the lowermost layer on the substrate 101. The anode 102 is formed of a transparent conductive thin film such as ITO. On the anode 102, an insulating layer 103 made of polyimide or the like is formed. The insulating layer 103 has an opening at a position where the anode 102 and the cathode 105 intersect (that is, a position where a pixel is formed). An organic EL layer 104 is formed in the opening of the insulating layer 103.

  The insulating layer 103 plays a role of defining an opening where the organic EL layer 104 and the anode 102 are in contact with each other. Further, the insulating layer 103 is disposed so as not to cause a short circuit between the anode 102 and the cathode 105. The organic EL layer 104 typically has a laminated structure including a hole injection layer, a hole transport layer, a light emitting layer, an electron injection layer, and the like. However, it is possible to have a different layer structure.

  On the organic EL layer 104, a cathode 105 made of a metal having high light reflectivity is provided in order to increase the light emission luminance. Although not shown here, a partition wall (not shown) made of, for example, a novolak resin or the like is provided for separating the cathode 105.

  A plurality of organic EL elements 110 are provided on the substrate 101, and a region where the organic EL elements 110 are formed becomes a display region. On the substrate 101, auxiliary wiring for supplying a signal to each organic EL element 110 is further provided. In FIG. 1, a portion of the auxiliary cathode wiring 109 connected to the cathode 105 is illustrated. The anode 102 and the cathode 105 of the organic EL element 110 are connected to respective auxiliary wirings, and these auxiliary wirings are extended outside the adhesive 108. A driving circuit (not shown) is mounted on the end of the substrate 101, and the anode 102 and the cathode 105 are each connected to the driving circuit via auxiliary wiring. By supplying a current from the drive circuit to the organic EL element 110, the organic EL element 110 can emit light and display a desired image.

  The counter substrate 106 is provided so that moisture and oxygen do not enter the panel. As the counter substrate 106, in addition to metals such as stainless steel, aluminum, or an alloy thereof, one or two or more types such as glass and acrylic resin can be used. The counter substrate 106 and the substrate 101 are sealed with an adhesive 108, and a sealing space (region) is formed between the counter substrate 106 and the substrate 101. In addition to the organic EL element 110, a viscous moisture absorbing member 107 for suppressing the influence of moisture and oxygen on the organic EL element 110 and maintaining stable light emission characteristics is disposed in the sealed space. The viscous moisture absorbing member 107 is disposed on the counter substrate 106 and on the surface facing the organic EL element 110.

  The viscous hygroscopic member 107 of this embodiment is a hygroscopic member having a predetermined viscosity. The viscous hygroscopic member 107 has such a viscosity that the adsorbent does not flow. It adheres to the coated surface in the form of cream or gel. As the adsorbent, one that physically or chemically adsorbs moisture, such as activated alumina, molecular sieves, calcium oxide, and barium oxide, is used. For example, the viscous moisture absorbing member 107 is configured by mixing a predetermined amount of an adsorbent in an inert liquid made of fluorinated oil, or a predetermined amount of adsorbent is added to an inert gel-like member such as a fluorinated gel. It is obtained by mixing. Examples of the fluorine-based oil include poly-trifluoro-chloroethylene, poly-fluoroalkylene glycol, and the like. The viscous hygroscopic member 107 is disposed with a constant interval d so as not to contact the inner side surface of the recess formed in the counter substrate 106.

  For example, the viscous moisture absorbing member 107 can be configured by mixing a predetermined amount of adsorbent in an inert liquid or an inert gel-like member made of silicon-based oil. As this silicone oil, dimethylsilicones such as methylpolysiloxane, octamethyltrisiloxane, decamethyltetrasiloxane, cyclic dimethylsilicones such as decamethylcyclopentasiloxane, octamethylcyclotetrasiloxane, and polymethylsiloxane having a cyclic structure, There are methylphenyl silicons such as methylphenylpolysiloxane and polysiloxanes having a phenyl group in addition to a methyl group.

  Other silicone oils such as trimethylsiloxysilicic acid and methyl-modified polysiloxane, polyoxyethylene / methylpolysiloxane copolymer, poly (oxyethylene, oxypropylene) methylpolysiloxane copolymer, etc. There are silicon, methylhydrogen polysiloxane and the like. The mixing ratio of the silicon-based oil and the adsorbent can be, for example, about 25 to 60 wt% so that the silicon-based oil and the adsorbent are not separated. Preferably, the mixing ratio is about 40 to 60 wt%, and in this case, thixotropy can be enhanced. More preferably, the mixing ratio is about 50 to 60 wt% and can be stably applied by a dispenser. In this embodiment, as an example of the viscous moisture absorbing member 107 using silicon-based oil, a material in which 7.0 g of dimethylpolysiloxane (manufactured by Shin-Etsu Chemical Co., Ltd.) and 55 wt% of molecular sieves 8.5 g are mixed. Thus, it was possible to stably apply the viscous hygroscopic member 107 having high thixotropy without using a dispenser.

  Next, the manufacturing method of the organic EL display device according to the present invention will be described with reference to FIG. FIG. 2 is a flowchart showing a manufacturing process of the organic EL display device. The organic EL display device has a structure in which a plurality of organic EL elements 110 serving as pixels are arranged. The organic EL display device includes an organic EL panel 100 having an element substrate on which the organic EL element 110 is formed and a counter substrate for sealing the organic EL element, and a drive circuit that supplies a drive signal to the organic EL element 110. It has.

  First, a substrate 101 made of glass or the like for forming the organic EL element 110 is prepared (step S101). An anode material is deposited on the substrate 101 (step S102). The anode material is made of a transparent conductive thin film such as ITO. The anode material is formed on the substrate with good uniformity by, for example, vapor deposition or sputtering. Thereafter, it is patterned into a predetermined pattern shape by photolithography and etching (step S103), and this pattern becomes the anode 102.

  Next, an auxiliary wiring material (not shown) is formed on the anode 102 (step S104). As the auxiliary wiring material, a low-resistance metal material such as Al or an Al alloy is used, and can be formed by a vapor deposition method, a sputtering method, or the like. Further, in order to improve adhesion to the base or prevent corrosion, a barrier layer such as TiN or Cr may be formed in the lower layer or upper layer of the Al film to form the auxiliary wiring in a laminated structure. This barrier layer can also be formed by vapor deposition or sputtering.

  Next, this auxiliary wiring material is patterned by photolithography and etching to form an auxiliary wiring pattern (step S105). For the etching, an etching solution made of a mixed solution of phosphoric acid, acetic acid, nitric acid or the like can be used. It is also possible to form the anode material and the auxiliary wiring material in order, and then pattern the auxiliary wiring material and the anode material in order. The anode 102 and the cathode 105 to be formed later are connected to a drive circuit mounted on the end portion of the substrate through this auxiliary wiring pattern, and a signal is supplied.

  Next, the insulating layer 103 is formed on the anode 102 (step S106). The insulating layer 103 can be made of an insulating material such as polyimide. The insulating layer 103 is formed by spin coating, and then formed into a predetermined pattern by means such as photolithography. The insulating layer 103 is provided with an opening at a position where the anode 102 and a cathode 105 described later intersect (that is, a position where a display pixel is formed). An organic EL layer 104 is formed in the opening.

  Next, a partition is formed for separation of the cathode 105 (step S107). For example, a novolac resin is spin-coated on the partition walls, patterned by a photolithography process, and then subjected to a photoreaction to form a cathode partition wall. It is preferable to use a negative type photosensitive resin so that the cathode partition has an inversely tapered structure. With such a structure, the cathode 105 can be separated from the cathode 105 because the portion that is shaded when viewed from the deposition source is not evaporated. Further, oxygen plasma or ultraviolet light may be irradiated in order to modify the surface of the ITO layer in the opening.

  Next, the organic EL layer 104 is laminated on the anode 102 formed in the opening of the insulating layer 103 by vapor deposition, coating, or the like (step S108). The organic EL layer 104 is often composed of a hole injection layer, a hole transport layer, a light emitting layer, an electron injection layer, and the like. However, it may have a different layer structure. For example, copper phthalocyanine (CuPc) can be used as the hole injection layer. Further, N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine (α-NPD) can be used as the hole transport layer. Tris (8-quinolinolato) aluminum (Alq3) can be used as the light emitting layer, and LiF can be used as the electron injection layer.

  Next, the cathode 105 is formed on the organic EL layer 104 (step S109). The cathode 105 is often made of a metal having high light reflectance such as Mg, MgAg, MgIn, Al, and LiAl in order to increase the emission luminance. It can be formed by physical vapor deposition (PVD) such as sputtering or ion plating. Thus, the organic EL element 110 is formed by stacking the anode 102, the insulating layer 103, the organic EL layer 104, and the cathode 105.

  Through these steps, an element substrate having a plurality of organic EL elements 110 formed on the substrate 101 is manufactured. The above-described process is an example in the case of an element substrate used for a typical organic EL panel.

  Next, a manufacturing process of the counter substrate 106 for sealing the organic EL element 110 will be described. As the counter substrate 106, in addition to metals such as stainless steel, aluminum, or an alloy thereof, a substrate made of one kind or two or more kinds such as glass and acrylic resin is prepared (step S201). Next, a predetermined amount of the viscous moisture absorbing member 107 is disposed on the counter substrate 106. That is, first, the viscous moisture absorbing member 107 is applied on the counter substrate 106 in a dry atmosphere with an inert gas (for example, dry nitrogen) or dry air from which moisture has been removed as much as possible (step S202). Subsequently, gas is blown onto the viscous moisture absorbing member 107 applied on the counter substrate 106 (step S203). The gas to be sprayed is preferably an inert gas, particularly nitrogen gas. In addition, the arrangement | positioning method (S202, S203) of the viscous moisture absorption member 107 is explained in full detail later.

  Next, an adhesive 108 for fixing the substrate 101 and the counter substrate 106 is applied (step S204). The adhesive 108 is provided on the outside of the viscous moisture absorbing member 107 using a dispenser, and is provided on the counter substrate 106 so as to surround the entire periphery of the display area. As the adhesive 108, an epoxy resin adhesive having low permeability such as moisture, a photocurable resin, or the like can be used.

  Next, the counter substrate 106 provided with the viscous moisture absorbing member 107 and the substrate 101 on which the organic EL element 110 is formed are bonded and sealed (step S110). After aligning the two substrates, the adhesive 108 can be cured and the two substrates can be bonded together by irradiating UV light while applying pressure. In this way, the organic EL panel 100 is manufactured.

  Through the above-described process, the space between the substrate 101 and the counter substrate 106 is sealed with the adhesive 108. Since the viscous moisture absorbing member 107 is disposed in the sealed space defined by the adhesive 108, the deterioration of the organic EL element 110 due to moisture or the like can be suppressed.

  Thereafter, a drive circuit and the like are mounted (step S111). On the substrate 101, auxiliary wiring is extended from the region surrounded by the adhesive 108. A terminal portion is formed at an outer end portion of the auxiliary wiring, and an anisotropic conductive film (ACF) is attached to the terminal portion to connect a TCP (Tape Carrier Package) provided with a drive circuit. The organic EL panel 100 is attached to the housing, and the organic EL display device is completed (step S112).

  Here, the arrangement method (steps S202 and S203) of the viscous hygroscopic member 107 will be described with reference to FIGS. 3, 4, and 5. FIG. FIG. 3 is a schematic schematic view showing a coating device 200 for the viscous moisture absorbing member 107.

  The coating apparatus 200 includes a stage 201 on which the counter substrate 106 is mounted, and a dispenser 202 for applying a viscous hygroscopic member 107 having viscosity. The dispenser 202 includes a needle 203 that discharges the viscous hygroscopic member 107. ing. In addition, the coating apparatus 200 includes a nozzle 204 that blows gas onto the viscous moisture absorbing member 107 that is discharged from the discharge port of the needle 203. In addition, the coating apparatus 200 includes an XYZ moving unit 205 including an actuator, a servo motor, and the like, and can move the dispenser 202 and the nozzle 204 to an arbitrary position and height. Further, a control device 206 capable of controlling the discharge amount of the viscous moisture absorbing member 107, the position and moving speed of the dispenser 202, the gas blowing position, and the like is provided.

  First, the counter substrate 106 is placed on the stage 201. Then, the dispenser 202 is lowered by the XYZ moving means 205, and the needle 203 is disposed close to the counter substrate 106 so that the needle 203 and the counter substrate 106 are at a predetermined distance. Next, the viscous moisture absorbing member 107 having viscosity is discharged from the discharge port of the needle 203 and applied onto the counter substrate 106. Then, the viscous hygroscopic member 107 can be applied by moving the needle 203 parallel to the application end point position while keeping the distance from the counter substrate 106 substantially constant by the XYZ moving means 205.

  The position of the viscous moisture absorbing member 107 to be applied on the counter substrate 106, the discharge amount, the moving speed of the dispenser 202, and the like can be arbitrarily set by the control device 206, and are controlled by a control signal output from the control device 206. . The viscous hygroscopic member 107 is always discharged from the application start point position to the application end point position, and is continuously applied on the counter substrate 106. When moving to the application end point position, the discharge of the viscous moisture absorbing member 107 and the movement of the dispenser 202 are stopped. At the stop position, the dispenser 202 is raised and the viscous hygroscopic member 107 and the needle 203 are separated. Before starting the raising of the dispenser 202 or during the raising of the dispenser 202, a gas is blown from the nozzle 204 to the application end portion of the viscous moisture absorbing member 107.

  At this time, if the gas is not blown at the application end point position and is raised as it is, the viscous hygroscopic member 107 having viscosity is dragged to the tip of the needle 203, causing horns or stringing. If sealing is performed in this state, display defects such as unevenness are caused by contact between the horn portions of the organic EL element 110 and the viscous moisture absorbing member 107. Further, the sticking of the viscous hygroscopic member 107 to the bonding portion between the element substrate and the counter substrate may be caused by stringing due to stringing. Therefore, when the dispenser 202 is raised, gas is blown from the nozzle 204 toward the discharge port of the viscous hygroscopic member 107 of the needle 203, thereby preventing horn or stringing of the viscous hygroscopic member 107 having viscosity.

  The shape of the viscous hygroscopic member 107 will be described with reference to FIG. FIG. 4 is a diagram illustrating a state where the viscous moisture absorbing member 107 is applied to the counter substrate 106 using the coating apparatus 200. FIG. 4A is a diagram showing a cross-sectional shape of the viscous moisture absorbing member 107 when the needle 203 is raised without blowing gas at the application end point position and the viscous moisture absorbing member 107 and the needle 203 are separated. (B) is a figure which shows the cross-sectional shape of the viscous hygroscopic member 107 at the time of raising the needle 203, when gas is sprayed on the discharge port of the viscous hygroscopic member 107 of the needle 203. FIG.

  As shown in FIG. 4A, when the gas is not blown at the application end point position and is lifted as it is, the viscous hygroscopic member 107 having viscosity is dragged to the tip of the needle 203 to form a horn or to draw the string. Wake up. Therefore, gas is blown from the nozzle 204 when the dispenser 202 is raised. By blowing the gas, the thickness of the application end portion of the viscous hygroscopic member 107 is reduced, and the formation of horns or stringing can be prevented. (FIG. 4B).

  Conventionally, as a countermeasure for stringing and horning of a viscous hygroscopic member, discharge (supply) of the viscous hygroscopic member 107 is stopped at the application end point before the movement end point in the movement of the needle 203, and in this state the needle The dispenser 202 (needle 203) was raised after moving the 203 to the end point of movement. In particular, in the case of a small organic EL panel such as a display of a mobile phone, the distance for applying the viscous moisture absorbing member 107 is insufficient. The application amount of the viscous hygroscopic member 107 was insufficient, and a predetermined amount could not be applied, and the desired hygroscopic performance could not be obtained.

  In this embodiment, the thickness of the viscous moisture absorbing member 107 once applied is controlled by gas blowing. For this reason, the dispenser 202 (needle 203) can be raised as it is at the application end point position. That is, the movement end point position of the needle 203 can be made the same as the application end point position of the viscous moisture absorbing member 107. Therefore, the viscous hygroscopic member 107 can be applied from the application end point position of the conventional viscous hygroscopic member 107 to the movement end point of the needle 203, and the application amount of the viscous hygroscopic member 107 can be increased.

  Further, as shown in FIG. 4B, the thickness t of the viscous moisture absorbing member 107 is preferably 90 to 120% of the thickness T of the counter substrate 106. More preferably, it is 95 to 110%. As a result, contact with the organic EL element 110 can be reliably prevented, and deterioration of display characteristics associated therewith can be suppressed.

  The gas blowing from the nozzle 204 can also be performed after the viscous moisture absorbing member 107 and the needle 203 are separated. After the application of the viscous hygroscopic member 107 is completed, the dispenser 202 (needle 203) is raised without gas blowing at the application end point position. The viscous moisture absorbing member 107 is leveled by blowing gas to the horn at the application end of the viscous moisture absorbing member 107, and the thickness of the viscous moisture absorbing member 107 is reduced. Thereby, the thickness of the viscous moisture absorbing member 107 is made smaller than the distance between the inner surface of the counter substrate 106 and the organic EL element 110, that is, the maximum thickness of the viscous moisture absorbing member 107 is less than the distance between the counter substrate 106 and the organic EL element 110. And the viscous hygroscopic member 107 can be prevented from coming into contact with the organic EL element 110. In addition to the application terminal portion of the viscous hygroscopic member 107, gas can be blown to other portions of the viscous hygroscopic member 107 in order to control the thickness of the viscous hygroscopic member 107.

  Moreover, this gas spraying can be performed not only for preventing the horn and stringing at the application end point position but also for expanding the area of the viscous moisture absorbing member 107. FIG. 5 is a view for explaining a case where gas is sprayed on the entire applied viscous moisture absorbing member 107. FIGS. 5A and 5B are views when the shape of the viscous moisture absorbing member 107 is viewed from above the counter substrate 106. FIG. 5A shows the shape of the viscous moisture absorbing member 107 when the gas is sprayed only at the application end point position, and FIG. 5B shows the viscous moisture absorbing member when the gas is sprayed over the entire applied viscous moisture absorbing member 107. The shape of 107 is shown.

  As shown in FIG. 5A, when the viscous hygroscopic member 107 is applied linearly, when the length of the viscous hygroscopic member 107 is L, L is preferably 5 to 80 mm. By doing so, it is possible to dispose the viscous moisture absorbing member 107 in an amount necessary for maintaining display characteristics.

  When the area of the viscous hygroscopic member 107 is expanded by blowing gas on the viscous hygroscopic member 107, the thickness of the viscous hygroscopic member 107 decreases as the area increases, so the thickness of the viscous hygroscopic member 107 applied by the dispenser 202 is reduced. It can be enlarged and more viscous hygroscopic members 107 can be applied. By increasing the application amount of the viscous moisture absorbing member 107, the moisture absorption performance can be improved, and defects due to moisture and the like can be more effectively suppressed. Moreover, even if it is the same application quantity, since the thickness can be made small, the contact of the viscous moisture absorption member 107 and an organic EL element can be prevented more reliably.

When the area of the viscous hygroscopic member 107 is enlarged, for example, when the counter substrate 106 having a thickness of 1.1 to 0.7 mm is provided with a recess having a depth of 0.55 to 0.35, the viscosity is increased. It is preferable that the area S of the hygroscopic member 107 is 100 to 2000 mm ² . For example, when the area S of the viscous hygroscopic member 107 is 100 mm ² , the viscous hygroscopic member 107 can be arranged at 5 mm × 20 mm. In addition, it is preferable that the viscous moisture absorbing member 107 is provided with a certain distance d so as not to contact the inner side surface of the recess formed in the counter substrate 106. By doing so, the viscous moisture absorbing member 107 does not enter the position of the adhesive 108, and when the counter substrate 106 and the substrate 101 on which the organic EL element is formed are bonded together, the bonding can be reliably performed. it can.

  The gas is blown onto the viscous hygroscopic member 107 after the application of the viscous hygroscopic member 107 by the dispenser 202, or the gas is blown onto the viscous hygroscopic member 107 while the viscous hygroscopic member 107 is being applied by the dispenser 202. Is possible. From the viewpoint of manufacturing efficiency, it is preferable to spray gas onto the viscous moisture absorbing member 107 simultaneously with the application of the viscous moisture absorbing member 107. By performing the viscous moisture absorbing member 107 and the gas blowing in parallel, the time required for the viscous moisture absorbing member 107 installation process can be shortened.

  As described above, in the viscous hygroscopic member arrangement process of this embodiment, the shape of the viscous hygroscopic member is deformed by blowing gas to the applied viscous hygroscopic member. This makes it possible to prevent contact between the viscous hygroscopic member and the organic EL element, or to increase the application amount of the viscous hygroscopic member. In addition, the deformation of the viscous hygroscopic member due to the gas can avoid an undesirable shape change of the viscous hygroscopic member due to separation of the application means such as a needle from the viscous hygroscopic member.

  The shape of the discharge port of the needle 203 may be any shape such as a circular shape or a rectangular shape. Moreover, although this form showed the example which used the dispenser 202 for application | coating of the viscous moisture absorption member 107, it is also possible to apply this invention to the hand-painting application | coating etc. which used application | coating means, such as a medicine spoon. Application of the viscous hygroscopic member of this embodiment is particularly suitable for manufacturing an organic EL panel, but it can also be applied to application of a viscous hygroscopic member to a substrate of another display panel.

It is a typical sectional view of the organic EL panel concerning this embodiment. It is a flowchart which shows the manufacturing process of the organic electroluminescent panel concerning this embodiment. It is a typical schematic diagram of an application device which applies a viscous hygroscopic member of this embodiment. It is a figure explaining the application state of the viscous moisture absorption member of this embodiment. It is a figure explaining the application state of the viscous moisture absorption member of this embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Organic EL panel 101 Substrate 102 Anode 103 Insulating layer 104 Organic EL layer 105 Cathode 106 Opposite substrate 107 Viscous moisture absorbing member 108 Adhesive 109 Cathode auxiliary wiring 200 Coating device 202 Dispenser 203 Needle 204 Nozzle 205 Moving means 206 Control device

Claims (12)

A method for manufacturing a display panel, comprising: a first substrate; a second substrate; and a display element formed in a sealed space between the first substrate and the second substrate,
Applying a viscous hygroscopic member on the second substrate;
Blowing a gas against the viscous moisture absorbing member applied on the second substrate to reduce the thickness of the viscous moisture absorbing member;
Sealing the first substrate and the second substrate with an adhesive so that the viscous moisture absorbing member is disposed in the sealed space;
Manufacturing method of display panel. The display element is formed on the first substrate;
The viscous moisture absorbing member is applied on a surface of the second substrate that faces the display element.
The manufacturing method of the display panel of Claim 1.   The gas is blown against the viscous moisture absorbing member applied on the second substrate so that the viscous moisture absorbing member has a thickness that does not contact a display element formed on the first substrate. The manufacturing method of the display panel of description.   The display panel manufacturing method according to claim 1, wherein the gas is blown so that a thickness of an application terminal portion of the viscous moisture absorbing member is reduced. A method for manufacturing a display panel, comprising: a first substrate; a second substrate; and a display element formed between the first substrate and the second substrate,
Applying a viscous hygroscopic member on the second substrate;
The gas is blown onto the viscous moisture absorbing member applied on the second substrate to deform the shape of the viscous moisture absorbing member,
Fixing the first substrate and the second substrate with an adhesive;
Manufacturing method of display panel.   The method for manufacturing a display panel according to claim 1, wherein an application area of the viscous hygroscopic member is expanded by blowing a gas to the viscous hygroscopic member. A stage on which a substrate is placed;
A dispenser that moves relative to the stage and applies a viscous hygroscopic member to the substrate on the stage;
A nozzle for blowing gas to the viscous moisture absorbing member applied on the substrate;
A device for applying a viscous moisture absorbing member. The said nozzle ejects | emits gas toward the discharge outlet of the said dispenser, The coating device of the viscous moisture absorption member of Claim 7. A display panel is formed by forming a display element on a first substrate, and a second substrate sealing the display element is fixed to the first substrate.
Applying a viscous hygroscopic member linearly to the surface of the second substrate facing the display element;
A gas is blown to the end of the viscous moisture-absorbing member after being applied, so that the thickness is not more than a predetermined thickness.
Manufacturing method of display panel.   The method for manufacturing a display panel according to claim 9, wherein a distance applied linearly when applying the viscous moisture absorbing member is 5 to 80 mm. 11. The display panel manufacturing method according to claim 9, wherein the viscous moisture absorbing member is applied so as to occupy an area of 100 to 2000 mm ^{2 on} a surface parallel to the inner surface of the second substrate. A recess having a depth of 0.55 to 0.35 mm is formed on one surface of a transparent substrate having a thickness of 1.1 to 0.7 mm, a viscous member is placed in the recess, and the viscous moisture absorbing member is in contact with the inner surface of the recess. A sealing substrate in which the surface area of the viscous moisture-absorbing member that is arranged without any gap and is parallel to the inner surface of the transparent substrate is 100 to 2000 mm ² .

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