JP2009199851A - Repairing device and method of organic electroluminescent panel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a repairing device and method for a flexible organic EL panel enabled to suppress damage of a defective point from affecting the surroundings as much as possible. <P>SOLUTION: The repairing device 10 is provided with a laser irradiating device 12 and a heat-absorbing member 14. In the repairing method, (1) the heat-absorbing member 14 is arranged in front of a first film 22, (2) the laser irradiating device 12 is moved toward above the defective point 36, and laser is irradiated on the point 36. Because of the laser irradiation, a metal electrode 34 at the defective point 36 is evaporated, and the defective point ceases to emit light. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a repair device and a repair method for a flexible organic EL panel.

  In recent years, attention has been paid to the practical use of organic EL panels. Unlike the liquid crystal panel, the organic EL panel can be configured flexibly.

  A flexible organic EL panel 20 shown in FIG. 5 is formed between a light transmissive first film 22, a second film 24 facing the first film 22, and the first film 22 and the second film 24. And an organic EL element 26. The organic EL element 26 is laminated on the first film 22. In order to seal the organic EL element 26, the peripheral edges of the films 22 and 24 are bonded together with an adhesive 28. The 2nd film 24 and the organic EL element 26 are adhere | attached with an adhesive agent as needed. In FIG. 5, the number of the organic EL elements 26 is one, but actually, a large number of organic EL elements 26 are arranged vertically and horizontally.

  The organic EL element 26 has a structure in which a transparent electrode 30, an organic layer 32, and a metal electrode 34 are laminated in this order from the first film side. The transparent electrode 30 is ITO or the like, and the metal electrode 34 is Al or the like. The transparent electrode 30 becomes an anode and the metal electrode 34 becomes a cathode. In FIG. 5, the organic layer 32 is a single layer, but a structure in which a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, and an electron injection layer are stacked in order from the anode side may be used. In the light-emitting layer, electrons and holes are recombined, so that light is emitted when the electrons change from the ground state to the excited state and further return to the ground state. Since light is emitted from the first film side, the first film is light transmissive, and the second film is irrelevant whether light transmissive or not.

  Since the films 22 and 24 and the organic EL element 26 are flexible, the organic EL panel 20 becomes flexible. Unlike a liquid crystal panel, it can be arbitrarily curved and used.

  In addition, there is an organic EL panel 60 using a hard glass substrate 62 and a cap 64 instead of the films 22 and 24 (FIG. 6). The organic EL panel 60 cannot be arbitrarily curved like the liquid crystal panel. The glass substrate 62 has a thickness of about 700 μm, and the films 22 and 24 have a thickness of about 100 μm. The flexible organic EL panel 20 is considerably thinner.

  The organic EL panel 20 has a large number of organic EL elements 26 arranged vertically and horizontally, and it is quite difficult to manufacture all the organic EL elements 26 without defects. For example, the organic EL panel 20 is manufactured in a clean room, but there are cases where the electrodes are short-circuited or reduced in resistance due to dust generated in the manufacturing apparatus. The current leaks at the defective portion 36 and becomes a bright spot, degrading the display quality.

  For this reason, it is common to detect a defect during the manufacturing process of the organic EL panel 20 and perform repair. For example, a defect is detected from the first film side, and the defect portion 36 is irradiated with a laser L. The metal electrode 34 at the defective portion 36 is evaporated by the laser L, and the defective portion 36 is increased in resistance. The defective portion 36 does not emit light by the repair, and it becomes difficult for the user to recognize the defective portion 36.

  As shown in FIG. 7, it is assumed that the amount of heat for evaporating the metal electrode 34 is Q1. At the time of repair, the organic layer 32 is given a heat quantity Q2 that is much higher than the heat quantity Q1. This is because (1) it is necessary to increase the output of the laser L in consideration of the amount of heat absorbed by the organic layer 32 in addition to the amount of heat given to the metal electrode 34, and (2) the laser L passes through the organic layer 32. This is because the amount of heat applied to the metal electrode 34 is larger in the organic layer 32.

  In addition, since the flexible organic EL panel 20 is very thin and has a small amount of material for releasing heat, such as the glass substrate 62, a large amount of heat is also conducted around the defect portion 36. Specifically, in the case of the organic EL panel 60 of FIG. 6, heat conduction as indicated by the arrow Tb occurs in the glass substrate 62, but the heat conduction of the flexible organic EL panel 20 is only in the direction of the arrow Ta. (FIG. 5). The organic EL element 26 around the defective portion 36 may be damaged by heat. The non-light emitting area is widened by repair, and the display quality is lowered.

  If the output of the laser L is reduced so that heat is not transmitted to the periphery of the defective portion, repair cannot be performed.

  If the laser L is irradiated from the metal electrode side, the organic layer 32 is not irradiated with the laser L. It is considered that the amount of heat given to the organic layer 32 is small, and damage to the organic layer 32 can be reduced. However, the metal electrode 34 is opaque and the defective portion 36 cannot be recognized. Therefore, laser irradiation from the metal electrode side is not performed. When the second film 24 becomes opaque, the defective portion 36 cannot be recognized in the same manner, and the second film 24 is also damaged by the laser L.

  If the coordinates of the defective portion 36 are known and an alignment mark is provided at the corner of the organic EL panel 20, the laser irradiation device 52 is automatically moved to the defective portion 36 by computer control, and the laser L is irradiated from the metal electrode side. It can be thought of as possible. However, the organic EL element 26 is very fine, and the final laser irradiation position is visually confirmed, and the laser irradiation position is finely adjusted as necessary. Automatic laser irradiation from the metal electrode side is likely to fail because fine adjustment is not possible.

  Patent Document 1 discloses a repair method using a laser. However, the cited document 1 is a repair of an array substrate for a liquid crystal panel, not an organic EL panel. Cited Document 1 irradiates a laser from the transparent electrode side, and if it is simply applied to an organic EL panel, it also damages the periphery of the defect. Cited Document 1 is repairing an array substrate, and sealing is not performed. Since the organic EL element is deteriorated by oxygen or moisture, in order to perform the repair by the method of the cited document 1, it must be performed in an inert gas atmosphere, which is very difficult.

  Patent Document 2 discloses a method of forming an organic layer again after removing a defective portion with a laser. Cited Document 2 irradiates a laser having a wavelength specialized for cutting a molecular chain of an organic layer. However, in order to improve the light emission efficiency, the organic layer is generally a plurality of layers, and it is a problem whether all the plurality of layers made of different materials can be removed by the method of Patent Document 2. This point is not disclosed in Patent Document 2. In order to confirm the light emission of the organic layer, it is necessary to sandwich the organic layer between the two electrodes. However, according to the method of Cited Document 2, the upper electrode cannot be formed, and the light emission cannot be confirmed.

  Patent Document 3 discloses an organic EL panel repair device. However, it is an apparatus for an organic EL panel using a glass substrate, and is not a repair apparatus for a flexible organic EL panel. Note that Patent Document 4 is an apparatus that performs an inspection without damaging the organic EL panel, and does not relate to a repair after the inspection.

JP 2000-347217 A JP 2004-119243 A JP 2007-42498 A JP 2005-83951 A

  The objective of this invention is providing the repair apparatus and repair method which made the damage to the circumference | surroundings of a defective part as small as possible with respect to a flexible organic electroluminescent panel.

  As described above, the organic EL panel has an organic EL element between the light transmissive first film and the second film. In the organic EL element, a transparent electrode, an organic layer, and a metal electrode are sequentially laminated from the first film side. In order to seal the organic EL element, the peripheral portions of the first film and the second film are bonded with an adhesive.

  The repair device of the organic EL panel includes a heat absorbing member and a laser irradiation device that irradiates a defective portion with a laser. Laser irradiation is performed after attaching a heat absorbing member to the organic EL panel.

  A liquid that fills the gap between the organic EL panel and the heat absorbing member is included, and the liquid includes a fluorine-based inert liquid. The heat absorbing member includes a light transmissive glass plate.

  In the repair method using the repair device, (1) a heat absorbing member is arranged on the front surface of the organic EL panel, and (2) a laser is irradiated from the first film side to the defective portion through the heat absorbing member.

  Before the above (1), a liquid is applied to the front surface of the place where the heat absorbing member is to be disposed, and when the heat absorbing member is disposed, the gap between the heat absorbing member and the organic EL panel is filled with the liquid. Like that.

  According to the present invention, since heat generated by laser irradiation is conducted to the heat absorbing member, damage due to heat of the organic layer can be suppressed as much as possible. There is little risk of expanding the non-light emitting area by repair. By filling the space between the organic EL panel and the heat absorbing member with a liquid, heat conduction from the organic EL panel to the heat absorbing member can be efficiently performed. If the heat absorbing member is a light transmissive glass plate, the heat absorbing member does not interfere with laser irradiation. If the liquid is a fluorine-based inert liquid, the organic EL panel is not deteriorated by the liquid.

  Embodiments of the present invention will be described with reference to the drawings. The flexible organic EL panel to be repaired is the same as the organic EL panel described in the related art, and the description of the organic EL panel is omitted.

  The repair device 10 of the present invention is a device that performs repair with a laser L as in the conventional case (FIG. 1). The repair device 10 includes a laser irradiation device 12 and a heat absorption member 14.

The laser irradiation device 12 is various laser irradiation devices such as YAG, excimer, semiconductor, and gas. The wavelength of the laser L is about 200 to 1100 nm, and the output is about 2 × 10 ⁻³ to 4 × 10 ⁻² mJ. The metal electrode 34 at the defective portion 36 is evaporated by the laser L to increase the resistance of the defective portion 36.

  The heat absorbing member 14 uses a glass plate. The heat absorbing member 14 is disposed in contact with the front surface of the first film 22. In the present description, the front surface of the first film 22 is a surface opposite to the transparent electrode 20.

The heat absorbing member 14 is light transmissive so that the defective portion 36 can be visually recognized and the laser L can be transmitted. The thickness of the heat absorbing member 14 is about 700 μm, and the thermal conductivity is about 0.6 to ¹ Wm ⁻¹ K ⁻¹ . Since the thickness of the 1st film 22 is very thin, the structure which has arrange | positioned the heat absorption member 14 approximates the organic electroluminescent panel using a glass substrate. Therefore, the heat generated by the repair can be released to the heat absorbing member 14 as in the case of the organic EL panel using the glass substrate.

  When repairing, the organic EL panel 20 is arranged so that the first film 22 faces upward. This is because when the heat absorbing member 14 is disposed on the front surface of the first film 20, the heat absorbing member 14 is in close contact with the first film 22 by its own weight. When the heat absorbing member 14 and the first film 22 are in close contact with each other, heat conduction is improved. The first film 22 may be slightly inclined with respect to the upper side.

  Since the heat absorbing member 14 only needs to absorb heat at the defect portion 36 and its periphery, the heat absorbing member 14 does not need to have a size that covers the entire first film 22. The heat absorption member 14b which covers a part may be sufficient. If it is the heat absorption member 14 of the magnitude | size which covers all the 1st films 22, it can repair by placing the heat absorption member 14 on the 1st film 22 regardless of the position of the defect location 36, and work efficiency is high. good.

  In addition, the repair device 10 is a holder for the organic EL panel 20, a means for supporting the laser irradiation device 12, a means for moving the laser irradiation device 12 above the defective portion 36, a means for enlarging and displaying the defective portion 36, Includes computers that control operations. After the laser irradiation apparatus 12 is moved to the vicinity of the defect portion 36 by computer control, the defect portion 36 is enlarged and displayed, and the laser irradiation position is finely adjusted while visually observing. A robot that automatically arranges the heat absorbing member 14 may be provided. In addition, the repair device 10 includes means for lighting the organic EL panel 20. In order to adjust the irradiation position of the laser L, the organic EL panel 20 is turned on so that the defective portion 36 can be identified.

  Although it is necessary to detect the defective part 36 before performing repair, the detection method of the defective part 36 is not specifically limited in this invention. For example, the method disclosed in Patent Document 4 shown in the prior art may be used.

  The repair method using the repair device 10 is as follows: (1) the heat absorbing member 14 is disposed on the front surface of the first film 22; (2) the laser irradiation device 12 is moved over the defect portion 36; Laser irradiation. The metal electrode 34 at the defective portion 36 is evaporated by the laser irradiation, and the defective portion 36 does not emit light.

  Unlike the prior art, the heat absorbing member 14 is attached to the front surface of the first film 22. As a result, heat generated during laser irradiation can be conducted to the heat absorbing member 14, and the amount of heat conducted to the organic layer 32 can be reduced. Damage to the organic layer 32 can be suppressed as much as possible.

  Even if the surfaces of the first film 22 and the heat absorbing member 14 appear flat to the naked eye, they have fine irregularities on a macro scale. Further, the organic EL panel 20 is flexible, and may be curved macroscopically even if it looks flat with the naked eye. Therefore, it is quite difficult to bring the organic EL panel 20 and the heat absorption member 14 into close contact with each other. If the heat absorbing member 14 is simply disposed on the front surface of the first film 22, a fine gap may occur.

  Therefore, the liquid 16 is filled in the gap between the first film 22 and the heat absorbing member 14. Heat is efficiently generated from the first film 22 to the heat absorbing member 14 by the liquid 16. For convenience of explanation, the liquid 16 is layered in FIG. 1 but actually fills the gap between the first film 22 and the heat absorbing member 14.

  As the liquid 16, a fluorine-based inert liquid is used. Examples of the liquid 16 include Galden (trade name) and Florinato (trade name). These liquids 16 have higher thermal conductivity than air, and assist heat conduction to the heat absorbing member 14. Since it is a fluorine-based inert liquid, the organic EL panel 20 is hardly deteriorated.

  In order to fill the liquid 16 in the gap between the first film 22 and the heat absorbing member 14, the liquid 16 is applied to the front surface of the first film 22 before (1). The repair device 10 includes a dispenser for applying the liquid 16. The liquid 16 may be applied to the defective portion 36 and its periphery, and it is not necessary to apply the liquid 16 to the entire surface of the first film 22. The dispenser may automatically apply the liquid 16 to the defective portion 36 under computer control. If there are a plurality of defective portions 36, the liquid 16 is applied to all the defective portions 36. After the repair, the heat absorbing member 14 is removed and the liquid 16 is wiped off. A robot that automatically removes the heat absorbing member 14 and wipes the liquid 16 may be provided.

  By filling the gap between the first film 22 and the heat absorbing member 14 with the liquid 16, heat conduction from the first film 22 to the heat absorbing member 14 can be improved. Heat damage to the organic layer 32 can be minimized.

  As mentioned above, although embodiment of this invention was described, this invention is not limited to said embodiment. For example, the heat absorbing member 14 may be a heat absorbing member 14c in which a glass plate 15a and a metal plate 15b are combined (FIG. 3). There is a glass plate 15a in the center of the metal plate 15b. When the laser L is irradiated, the laser L passes through the glass plate 15a. The glass plate 15a should just have the magnitude | size which the laser L passes at least. The metal plate 15b has a higher thermal conductivity than the glass plate 15a and absorbs a lot of heat.

  The heat absorbing member 14 is attached after applying the liquid 16 on the first film 22 of the defective portion 36, but the heat absorbing member 14 is attached to the first film 22 after applying the liquid 16 to the heat absorbing member 14. May be.

  If only the peripheral edges of both films are bonded at the time of sealing, a gap is formed because the second film 24 and the metal electrode 34 are not bonded, and heat is not easily transmitted to the second film 24. However, if the second film 24 and the metal electrode 34 are bonded with an adhesive, the heat generated in the organic layer 32 and the metal electrode 34 is also conducted to the second film 24. Therefore, heat can be absorbed also from the second film 24. In this case, you may attach the heat absorption member 14 to the front surface of the 2nd film 24 like the repair apparatus 10c of FIG. Since the laser L is irradiated from the first film side, it is not necessary to make the heat absorbing member 14 on the second film side transparent, and a metal having high thermal conductivity may be used. The heat absorbing member 14 and the holding base for the organic EL panel 20 may be integrated. In this description, the front surface of the second film 24 is the surface opposite to the metal electrode 34.

  Similarly to the above embodiment, the gap between the second film 24 and the heat absorbing member 14 is filled with the liquid 16 to improve heat conduction. The heat absorbing member 14 may be attached to the second film 24 after the liquid 16 is applied to the heat absorbing member 14.

  The heat absorbing member 14 may be attached to both sides of the first film 22 and the second film 24 to absorb heat. The gap between the first film 22 and the heat absorbing member 14 and the gap between the second film 24 and the heat absorbing member 14 are filled with the liquid 16 to improve heat conduction.

  In addition to automatically applying the liquid 16 with a dispenser, the operator may apply it manually. As long as the organic EL panel 20 is not damaged, the organic EL panel 20 is not limited to a fluorine-based inert liquid, and a liquid having high thermal conductivity may be used. Metal fine powder may be mixed into the liquid 16 to increase the thermal conductivity of the liquid 16. Since the attenuation of the laser L increases when the amount of the metal fine powder is large, the amount of the metal powder is determined in consideration of the output and attenuation of the laser L.

  In addition, the present invention can be carried out in a mode in which various improvements, modifications, and changes are added based on the knowledge of those skilled in the art without departing from the spirit of the present invention.

It is a figure which shows the structure of a repair apparatus. It is the figure comprised so that a heat absorption member might cover a part of 1st film. It is the figure which comprised the heat absorption member with the glass plate and the metal. It is the figure which has arrange | positioned the heat absorption member in the front surface of the 2nd film. It is a figure which shows the structure of the conventional repair apparatus. It is the figure which applied the conventional repair apparatus to the organic electroluminescent panel using a glass substrate. It is the figure which showed the temperature change of the organic layer and metal electrode at the time of repair.

Explanation of symbols

10: Repair device 12: Laser irradiation device 14: Heat absorption member 16: Liquid 20: Organic EL panel 22, 24: Film 26: Organic EL element 28: Adhesive 30: Transparent electrode 32: Organic layer 34: Metal electrode 36: Defect location L: Laser

Claims (5)

A light transmissive first film;
A second film facing the first film;
An organic EL element formed between the first film and the second film, in which a transparent electrode, an organic layer, and a metal electrode are sequentially laminated from the first film side;
An organic EL panel repair device for repairing a defective portion of an organic EL panel including
A heat absorbing member disposed on the front surface of the first film, the second film, or both;
A laser irradiation device for irradiating the defect portion with a laser; and
Repair device including The repair apparatus of Claim 1 containing the liquid with which the clearance gap between the said organic electroluminescent panel and a heat absorption member is included. The repair device according to claim 2, wherein the heat absorbing member includes a light transmissive glass plate, and the liquid includes a fluorine-based inert liquid. A light transmissive first film;
A second film facing the first film;
An organic EL element formed between the first film and the second film, in which a transparent electrode, an organic layer, and a metal electrode are sequentially laminated from the first film side;
A method for repairing an organic EL panel in which a defective portion of an organic EL panel including a laser is repaired with a laser,
Disposing a heat absorbing member on the front surface of the first film, the second film, or both;
Irradiating the defect with a laser;
Including repair method. The repair method of Claim 4 including the step which fills the liquid into the clearance gap between a said 1st film, a 2nd film, or both, and a heat absorption member.

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