JP2010175680A - Method for producing display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a display device having excellent reliability that ensures attachment of a nonflexible display panel and a heat dissipation plate by suppressing generation of air bubbles caused by intrusion of air in the attachment, obtaining sufficient adhesive strength and also performs good heat conduction from the display panel to the heat dissipation plate. <P>SOLUTION: A method of producing the display device 1, in which the display panel 12 and the heat dissipation plate 11 are attached in an opposing position through a pressure sensitive adhesive sheet 20 having adhesiveness on both sides, has a first step of forming a plurality of channels 20a on the pressure sensitive adhesive sheet 20 and a second step of attaching the display panel 12 and the heat dissipation plate 11 through the pressure sensitive adhesive sheet 20 after forming the plurality of channels 20a on the pressure sensitive adhesive sheet 20. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a display device.

  Conventionally, there are flat panel displays (hereinafter referred to as display panels) such as liquid crystal displays, plasma display panels, and organic EL (Electro-Luminescent) displays. When fixing such a display panel to a holding member, for example, there is a method using a stopper such as a screw, but the display panel substrate is generally made of glass, and it is difficult to fix the display panel substrate so as not to be scratched or broken. It is. Therefore, when fixing the display panel to the holding member, a method using an adhesive sheet having adhesiveness on both sides is generally used. On the other hand, in order to dissipate heat generated when the display panel is driven, it is necessary to cool the display panel. The display panel is cooled by, for example, attaching a heat radiating plate that also serves as a holding function to the back surface of the display panel with an adhesive sheet having high thermal conductivity.

  FIG. 9 is a cross-sectional view showing a schematic configuration of a display device 1000 according to the prior art. The display device 1000 is configured such that the display panel 1012 and the heat radiating plate 1011 are bonded to each other via an adhesive sheet 1020 having adhesiveness on both sides. Between the display panel 1012 and the pressure-sensitive adhesive sheet 1020, air bubbles 1020a generated due to air entrainment at the time of bonding remain.

  In general, it is difficult to securely bond the display panel and the heat sink so that no bubbles remain because the display panel substrate and the heat sink are rigid and have no flexibility. Specifically, when one of the heat sink and the display panel substrate (one substrate) and the adhesive sheet are bonded together, since the adhesive sheet has flexibility, the space between the one substrate and the adhesive sheet. The pressure-sensitive adhesive sheet can be bent and pressed together so that air does not enter and bubbles remain. However, after laminating one substrate and the adhesive sheet, when laminating one substrate and the other substrate, the one substrate already bonded with the adhesive sheet cannot be bent. Air enters between them and bubbles are generated. If the generated bubbles remain without being removed, the bonding area between the display panel and the heat sink is reduced. When the adhesion area is thus reduced, sufficient adhesion strength cannot be obtained, and heat conduction from the display panel to the heat sink cannot be performed satisfactorily, and the reliability of the obtained display device is lowered.

  On the other hand, there is a method in which the bonding process is performed in a reduced-pressure atmosphere so that bubbles are not generated between the substrate and the adhesive sheet. However, the method performed in a reduced pressure atmosphere is not preferable in terms of productivity and cost because the manufacturing process is complicated and an apparatus is required.

  Various techniques for solving such a problem have been studied. For example, in Patent Documents 1 and 2, as a structure that suppresses the generation of bubbles due to the intrusion of air at the time of bonding, one surface of a substrate is used. An adhesive sheet is disclosed in which a plurality of grooves having a predetermined pattern are formed in the formed adhesive layer. Patent Documents 3 and 4 disclose a technique for forming a plurality of grooves for releasing air in a structure that is an adherend of an adhesive sheet. Patent Documents 5 and 6 disclose techniques for improving the wettability of the pressure-sensitive adhesive layer of the pressure-sensitive adhesive sheet and improving the adhesion by providing a hydrophilic film between the pressure-sensitive adhesive sheet and the adherend.

JP 2002-221905 A JP 2006-45297 A JP 2001-152100 A JP 2006-198917 A JP 2004-62055 A JP 2008-102229 A

In the techniques of Patent Documents 1 to 6, it is considered that the generation of bubbles due to the intrusion of air can be suppressed when members having inflexibility are bonded together, but there are also the following problems.
In Patent Documents 1 and 2, since the pressure-sensitive adhesive layer needs to be patterned, when the pressure-sensitive adhesive sheet is not a base material and only the pressure-sensitive adhesive layer is used, buttering becomes difficult, which is not preferable in terms of productivity. Moreover, since the groove | channel of a predetermined pattern is previously formed in the adhesive sheet, the adhesive sheet of arbitrary patterns may not be selected. Moreover, in patent document 3 and 4, since a fine groove | channel is formed in the structure itself used as the adhesion body of an adhesive sheet, it is unpreferable in terms of productivity or cost. Moreover, in patent document 5 and 6, the coating process of the hydrophilic film provided between an adhesive sheet and a to-be-adhered body, a drying process, and the management process of an application quantity are needed, and a manufacturing process will be complicated.

  The present invention has been made in view of such circumstances, and when bonding a non-flexible display panel and a heat dissipation plate, the generation of air bubbles due to the intrusion of air is suppressed and the bonding is performed sufficiently. An object of the present invention is to provide a display device with excellent reliability that can obtain a good adhesive strength and can conduct heat from a display panel to a heat sink.

In order to solve the above-described problems, a method for manufacturing a display device according to the present invention is a method for manufacturing a display device in which a display panel and a radiator plate are bonded to each other through an adhesive sheet having adhesiveness on both sides. A first step of forming a plurality of grooves in the pressure-sensitive adhesive sheet; and a second step of bonding the display panel and the heat dissipation plate through the pressure-sensitive adhesive sheet after forming the plurality of grooves in the pressure-sensitive adhesive sheet; It is characterized by having.
According to this manufacturing method, when a non-flexible display panel and a heat sink (adhered body) are bonded together, a plurality of air formed between the adhesive sheet and the adherend are formed on the adhesive sheet. It is discharged to the outside along the groove. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed, and a display panel and a heat sink can be bonded together reliably. Therefore, it is possible to obtain a display device with excellent reliability that can obtain sufficient adhesive strength and can conduct heat conduction from the display panel to the heat sink. Moreover, since the patterning of an adhesion layer is unnecessary like patent document 1 and 2, even when an adhesive sheet is a base materialless and it is only an adhesion layer, it does not affect productivity. Moreover, since the groove | channel of a predetermined pattern is not previously formed in the adhesive sheet, the groove | channel of arbitrary patterns can be formed. Moreover, since fine groove | channels are not formed in the structure itself used as the adherend of an adhesive sheet like patent document 3 and 4, there is no problem also in terms of productivity or cost. Moreover, since a hydrophilic film is not provided between the pressure-sensitive adhesive sheet and the adherend as in Patent Documents 5 and 6, the manufacturing process is not complicated. Therefore, a display device with low cost and excellent productivity can be obtained.

In this manufacturing method, you may have the process of bonding one surface of the said adhesive sheet to any one of the said heat sink and the said display panel before the said 1st process.
According to this manufacturing method, a plurality of grooves can be formed in the pressure-sensitive adhesive sheet with either the heat radiating plate or the display panel as a base. Therefore, it is not necessary to prepare a new base substrate when forming a plurality of grooves in the adhesive sheet, which is preferable in terms of productivity.

In this manufacturing method, you may have the process of bonding one surface of the said adhesive sheet to any one of the said heat sink and the said display panel after the said 1st process.
According to this manufacturing method, for example, when a release sheet is attached to the pressure-sensitive adhesive sheet, a plurality of grooves can be formed in the pressure-sensitive adhesive sheet using the release sheet as a base. Therefore, it is not necessary to prepare a new base substrate when forming a plurality of grooves in the adhesive sheet, which is preferable in terms of productivity.

In the manufacturing method, the plurality of grooves may be formed so as to open to the outside at at least one end of the pressure-sensitive adhesive sheet.
According to this manufacturing method, when the non-flexible display panel and the heat sink are bonded together, the air that has entered between the pressure-sensitive adhesive sheet and the adherend is released to the outside without stagnation. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and a display panel and a heat sink can be bonded together more reliably.

In the present manufacturing method, the plurality of grooves may be formed so as to communicate from one end of the pressure-sensitive adhesive sheet to the other end.
According to this manufacturing method, when the non-flexible display panel and the heat sink are bonded together, the air that has entered between the adhesive sheet and the adherend flows along the plurality of grooves without stagnation. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and a display panel and a heat sink can be bonded together more reliably.

In this manufacturing method, the plurality of grooves may be formed to be parallel to a vertical direction orthogonal to a normal direction of one surface of the display panel.
According to this manufacturing method, the pressure-sensitive adhesive sheet is not divided into a plurality in the vertical direction, which is the peeling direction, by the plurality of grooves. That is, the adhesion area in the peeling direction of the pressure-sensitive adhesive sheet can be sufficiently secured. Therefore, even when the display panel is used so as to be parallel to the vertical direction, a decrease in the adhesive strength between the display panel and the heat sink can be suppressed.

In this manufacturing method, the plurality of grooves may be formed to extend in parallel with a predetermined distance from each other.
According to this manufacturing method, when the non-flexible display panel and the heat radiating plate are bonded together, the air that has entered between the adhesive sheet and the adherend flows smoothly in a balanced manner along the plurality of grooves. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and a display panel and a heat sink can be bonded together more reliably.

In the manufacturing method, the plurality of grooves may be formed in a lattice shape.
According to this manufacturing method, when the non-flexible display panel and the heat radiating plate are bonded together, the air that has entered between the adhesive sheet and the adherend flows smoothly with a good balance along the plurality of grooves. . For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and a display panel and a heat sink can be bonded together more reliably.

In this manufacturing method, the plurality of grooves may be formed radially.
According to this manufacturing method, when the non-flexible display panel and the heat radiating plate are bonded together, the air that has entered between the adhesive sheet and the adherend flows smoothly with a good balance along the plurality of grooves. . For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and a display panel and a heat sink can be bonded together more reliably.

In the present manufacturing method, the plurality of grooves may be formed such that the depth of the plurality of grooves is smaller than the thickness of the pressure-sensitive adhesive sheet.
According to this manufacturing method, since the plurality of grooves are formed so as not to reach the base of the pressure-sensitive adhesive sheet, one surface of the pressure-sensitive adhesive sheet is flat without forming the plurality of grooves. Therefore, the adhesion area of the adherend can be sufficiently secured on one surface of the pressure-sensitive adhesive sheet, and the display panel and the heat radiating plate can be bonded together more reliably.

In the present manufacturing method, the plurality of grooves may be formed by pressing.
According to this manufacturing method, since a plurality of grooves having a predetermined pattern can be formed at a time by using a press die having a predetermined pattern, productivity can be improved.

It is a schematic diagram which shows schematic structure of the display apparatus in 1st Embodiment of this invention. It is a figure which shows the manufacturing process of the display apparatus in 1st Embodiment of this invention. FIG. 3 is a diagram showing a display device manufacturing process following FIG. 2. It is a schematic diagram which shows schematic structure of the display apparatus in 2nd Embodiment of this invention. It is a figure which shows the manufacturing process of the display apparatus in 2nd Embodiment of this invention. It is a figure which shows the manufacturing process of the display apparatus following FIG. It is a figure which shows the modification of the display apparatus in 2nd Embodiment of this invention. It is a figure which shows the difference in bubble distribution of the structure of the past and the structure of this invention. It is a schematic diagram which shows schematic structure of the conventional display apparatus.

  Embodiments of the present invention will be described below with reference to the drawings. This embodiment shows one aspect of the present invention, and does not limit the present invention, and can be arbitrarily changed within the scope of the technical idea of the present invention. Moreover, in the following drawings, in order to make each structure easy to understand, an actual structure and a scale, a number, and the like in each structure are different.

(First embodiment)
FIG. 1 is a schematic diagram showing an outline of an organic EL display device (display device) 1 according to the first embodiment of the present invention. Fig.1 (a) is sectional drawing along the BB line of FIG.1 (b). FIG.1 (b) is the top view seen from the direction of the AA line of Fig.1 (a). As shown in FIG. 1 (a) and FIG. 1 (b), the organic EL display device 1 of this embodiment includes an organic EL display (display panel) 12 via an adhesive sheet 20 having adhesiveness on both sides, The heat radiating plate 11 is bonded to the opposite position.

  The organic EL display 12 has a rectangular shape in plan view, and is made of a rigid body having no flexibility. Although not shown, the organic EL display 12 has a functional layer sandwiched between two electrodes, an anode and a cathode, and injects holes from the anode and electrons from the cathode into the functional layer. The organic EL device emits light when excited by recombination of holes and electric fields in the light emitting layer. The organic EL element generates excitons by recombining holes and electrons in the light emitting layer, emits energy to return from the excited state to the ground state, and extracts part of the emitted energy as light. It emits light.

  The adhesive sheet 20 is not bonded to the image display surface on the side from which the emitted light of the organic EL display 12 is emitted. That is, the adhesive sheet 20 is bonded to the surface (rear surface) opposite to the image display surface of the organic EL display 12, and the heat radiating plate 11 is fixed via the adhesive sheet 20.

  The pressure-sensitive adhesive sheet 20 has flexibility. The pressure-sensitive adhesive sheet 20 includes a filler that imparts thermal conductivity, and has high thermal conductivity. Thereby, the heat dissipation for cooling the organic EL display 12 can be performed efficiently. The adhesive sheet 20 is disposed in a region where the organic EL display 12 and the heat radiating plate 11 overlap. A plurality of grooves 20 a are formed on the side of the pressure-sensitive adhesive sheet 20 bonded to the back surface of the organic EL display 12. The plurality of grooves 20 a are open to the outside at both ends of the adhesive sheet 20. Further, the plurality of grooves 20 a communicate from one end of the adhesive sheet 20 to the other end.

  Next, each dimension is demonstrated. The dimension W is a distance between adjacent grooves in the plurality of grooves 20a (hereinafter referred to as a groove interval). The dimension D is the depth of the plurality of grooves 20a (hereinafter referred to as groove depth). The dimension T is the thickness of the adhesive sheet. The plurality of grooves 20a are formed to extend in parallel with a groove interval (predetermined interval) W therebetween. Moreover, the groove depth D is smaller than the thickness T of the adhesive sheet.

  The heat sink 11 has a rectangular shape in plan view and is made of a rigid body having no flexibility. The heat radiating plate 11 is made of a metal such as aluminum or copper having a high thermal conductivity, and has a cooling function for efficiently releasing the heat generated in the organic EL display 12 to the outside. In order to release the heat generated in the organic EL display 12 to the outside more efficiently, the heat radiating plate is not shown, for example, on the surface of the heat radiating plate 11 opposite to the surface fixed to the adhesive sheet 20. A plurality of thin plate-like heat radiation fins protruding from the surface of 11 can also be provided. The heat sink 11 also has a holding function for holding the organic EL display 12 via the adhesive sheet 20.

  The organic EL display 12 is held by the heat sink 11 and is erected so as to be parallel to the vertical direction. Similarly to the organic EL display 12, the plurality of grooves 20a formed to extend in parallel to the adhesive sheet 20 are also parallel to the vertical direction.

  Thus, even when the organic EL display 12 is used in a standing manner so as to be parallel to the vertical direction, the adhesive sheet 20 is not divided into a plurality in the vertical direction as the peeling direction by the plurality of grooves 20a. For this reason, the adhesive area of the adhesive sheet 20 in the vertical direction can be sufficiently secured, and a decrease in the adhesive strength between the organic EL display 12 and the heat sink 11 can be suppressed.

(Method for manufacturing organic EL display device)
Next, a method for manufacturing the organic EL display device 1 according to this embodiment will be described. 2 and 3 are process diagrams sequentially showing a method for manufacturing the organic EL display device 1. FIG. In this embodiment, after the process of bonding one surface of the pressure-sensitive adhesive sheet 20 to the heat radiating plate 11, the first process of forming the plurality of grooves 30 a in the pressure-sensitive adhesive sheet 20, and the formation of the plurality of grooves 20 a in the pressure-sensitive adhesive sheet 20 And a second step of bonding the organic EL display 12 and the heat radiating plate 11 via the adhesive sheet 20.

  When manufacturing the organic EL display device 1, first, as shown in FIG. 2A, a heat sink 11 manufactured by a method similar to the conventional method is prepared. Next, as shown in FIG. 2B, one surface of the pressure-sensitive adhesive sheet 20 is bonded to one surface (upper surface) of the heat radiating plate 11. Thereby, in the process of forming the plurality of grooves 20a in the pressure-sensitive adhesive sheet 20 described later, the plurality of grooves 20a can be formed in the pressure-sensitive adhesive sheet 20 with the radiator plate 11 as a base. Further, when one surface of the pressure-sensitive adhesive sheet 20 is bonded to the upper surface of the heat radiating plate 11, the pressure-sensitive adhesive sheet 20 is disposed so as not to protrude outside the heat radiating plate 11, in other words, within the heat radiating plate 11. .

  When one surface of the pressure-sensitive adhesive sheet 20 is bonded to the upper surface of the heat radiating plate 11, for example, a pressure roller 50 may be used. By using the pressure roller 50, the pressure-sensitive adhesive sheet 20 can be bent and bonded to the heat radiating plate 11 so as not to generate bubbles between the heat radiating plate 11 and the pressure-sensitive adhesive sheet 20. Here, a release sheet 21 is provided on the other surface of the pressure-sensitive adhesive sheet 20 so that the pressure roller 50 and the pressure-sensitive adhesive sheet 20 do not adhere when the pressure-sensitive adhesive sheet 20 is pressed using the pressure roller 50. Yes.

  Thereby, as shown in FIG.2 (c), the adhesive sheet 20 is bonded together on the upper surface of the heat sink 11, without generating a bubble between the heat sink 11 and the adhesive sheet 20. FIG. Next, as shown in FIG.2 (d), the peeling sheet 21 on the adhesive sheet 20 is peeled off. Thereby, the flat surface of the adhesive sheet 20 is exposed. Since a predetermined pattern of grooves is not formed in advance on the pressure-sensitive adhesive sheet 20 as in Patent Document 1, grooves of an arbitrary pattern can be formed.

  Next, as shown to Fig.3 (a), the some groove | channel 20a is formed in the adhesive sheet 20 bonded together on the upper surface of the heat sink 11. FIG. When forming the plurality of grooves 20a, for example, a cut roller 51 in which a plurality of circular blades 51b are provided on the rod-like member 51a with a predetermined interval W is used. Using this cut roller 51, a plurality of grooves 20a are formed in the pressure-sensitive adhesive sheet 20 so as to extend along the direction extending from one edge of the pressure-sensitive adhesive sheet 20 to the other edge (arrow in FIG. 3A). To do.

  Thereby, as shown in FIG.3 (b), the some groove | channel 20a is opened and formed in the both ends of the adhesive sheet 20. As shown in FIG. A plurality of grooves 20 a are formed so as to communicate from one end of the adhesive sheet 20 to the other end. The plurality of grooves 20a are formed to extend in parallel with each other with a groove interval W so as to correspond to a predetermined interval W between the plurality of circular blades 51b.

  Here, when the plurality of grooves 20 a are formed using the cut roller 51, the plurality of circular blades 51 b of the cut roller 51 are prevented from penetrating the adhesive sheet 20 and reaching the upper surface of the heat radiating plate 11. Thereby, the some groove | channel 20 is formed so that the groove depth D may become smaller than the thickness T of an adhesive sheet. For this reason, the surface of the pressure-sensitive adhesive sheet 20 on which the heat radiating plate 11 is bonded becomes a flat surface without the plurality of grooves 20 being formed.

  Next, as shown in FIG.3 (c), the organic EL display 12 is bonded together on the upper surface of the adhesive sheet 20 bonded by making the heat sink 11 into a base. A plurality of grooves 20 a are formed in the adhesive sheet 20 so as to open to the outside at both ends of the adhesive sheet 20. When the non-flexible organic EL display 12 and the heat radiating plate 11 are bonded together, from one end of the plurality of grooves 20a formed in the pressure-sensitive adhesive sheet 20 to the other end, the ends of the plurality of grooves 20a. It is preferable that the organic EL display 12 is stuck in the direction in which the organic EL display 12 extends. Thereby, the air that has entered between the pressure-sensitive adhesive sheet 20 and the organic EL display 12 is released to the outside without stagnation.

  In addition, since the plurality of grooves 20a are formed so as to communicate from one end of the pressure-sensitive adhesive sheet 20 to the other end, a plurality of air that enters between the pressure-sensitive adhesive sheet 20 and the organic EL display 12 does not stagnate. It flows along the groove 20. Further, since the plurality of grooves 20 a are formed to extend in parallel with each other with a groove interval W, the air that has entered between the adhesive sheet 20 and the organic EL display 12 extends along the plurality of grooves 20. It flows smoothly in a balanced manner. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed, and the organic EL display 12 and the heat sink 11 can be bonded together reliably. Through the above steps, the organic EL display device 1 of the present embodiment can be manufactured.

  According to the manufacturing method of the organic EL display device 1 of the present embodiment, the air that has entered between the pressure-sensitive adhesive sheet 20 and the organic EL display 12 when the non-flexible organic EL display 12 and the heat sink 11 are bonded together. Is discharged to the outside along the plurality of grooves 20 a formed in the pressure-sensitive adhesive sheet 20. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed, and the organic EL display 12 and the heat sink 11 can be bonded together reliably. Therefore, it is possible to obtain the organic EL display device 1 with excellent reliability that can obtain sufficient adhesive strength and can conduct heat from the organic EL display 12 to the heat sink 11 well. Moreover, since the patterning of an adhesion layer is unnecessary like patent document 1 and 2, even when the adhesive sheet 20 is a base material-less and only an adhesion layer, it does not affect productivity. Moreover, since the groove | channel of a predetermined pattern is not previously formed in the adhesive sheet 20, the groove | channel of arbitrary patterns can be formed. Moreover, since fine groove | channels are not formed in the structure itself used as the adherend of an adhesive sheet like patent document 3 and 4, there is no problem also in terms of productivity or cost. Moreover, since a hydrophilic film is not provided between the adhesive sheet 20 and the adherend as in Patent Documents 5 and 6, the manufacturing process is not complicated. Therefore, it is possible to obtain the organic EL display device 1 that is low in cost and excellent in productivity.

  Moreover, according to this manufacturing method, since it has the process of sticking one surface of the adhesive sheet 20 to the heat sink 11 before the 1st process, the several groove | channel 20a is carried out to the adhesive sheet 20 by using the heat sink 11 as a base. Can be formed. Therefore, it is not necessary to prepare a new base substrate when forming the plurality of grooves 20a in the adhesive sheet 20, which is preferable in terms of productivity.

  Moreover, according to this manufacturing method, since the several groove | channel 20a is formed so that it may open outside in the both ends of the adhesive sheet 20, when bonding the organic EL display 12 and the heat sink 11 which are not flexible, it bonds. The air that has entered between the adhesive sheet 20 and the organic EL display 12 is released to the outside without stagnation. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and the organic EL display 12 and the heat sink 11 can be bonded together more reliably.

  Moreover, according to this manufacturing method, since the some groove | channel 20a is formed so that it may connect from one edge part of the adhesive sheet 20 to the other edge part, the organic EL display 12 and the heat sink 11 which are not flexible, When sticking together, the air that has entered between the pressure-sensitive adhesive sheet 20 and the organic EL display 12 flows along the plurality of grooves 20a without stagnation. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and the organic EL display 12 and the heat sink 11 can be bonded together more reliably.

  Moreover, according to this manufacturing method, since the some groove | channel 20a is formed so that it may become in parallel with the perpendicular direction orthogonal to the normal line direction of one surface of the organic electroluminescent display 12, the adhesive sheet 20 has several The groove 20a is not divided into a plurality in the vertical direction, which is the peeling direction. That is, the adhesion area in the peeling direction of the pressure-sensitive adhesive sheet 20 can be sufficiently secured. Therefore, even when the organic EL display 12 is used so as to be parallel to the vertical direction, a decrease in the adhesive strength between the organic EL display 12 and the heat sink 11 can be suppressed.

  In addition, according to the present manufacturing method, the plurality of grooves 20a are formed so as to extend in parallel with each other with a groove interval W, so that the organic EL display 12 and the heat radiating plate 11 having no flexibility are bonded together. At this time, the air that has entered between the pressure-sensitive adhesive sheet 11 and the organic EL display 12 flows smoothly in a well-balanced manner along the plurality of grooves 20a. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and the organic EL display 12 and the heat sink 11 can be bonded together more reliably.

  Moreover, according to this manufacturing method, since the groove depth D is formed to be smaller than the thickness T of the pressure-sensitive adhesive sheet, the plurality of grooves 20a do not reach the heat radiating plate 11 serving as the foundation of the pressure-sensitive adhesive sheet 20. . For this reason, one surface of the pressure-sensitive adhesive sheet 20 becomes a flat surface without forming the plurality of grooves 20a. Therefore, the adhesion area of the heat sink 11 can be sufficiently secured on one surface of the pressure-sensitive adhesive sheet 20, and the organic EL display 12 and the heat sink 11 can be bonded more reliably.

  Note that the display panel according to the present embodiment uses the organic EL display 12, but is not limited thereto. For example, instead of the organic EL display 12, a liquid crystal display or a plasma display panel may be used.

  In addition, in the process of bonding one surface of the pressure-sensitive adhesive sheet 20 according to the present embodiment, the one surface of the pressure-sensitive adhesive sheet 20 and the heat radiating plate 11 are bonded together, but this is not a limitation. For example, the organic EL display 12 may be bonded to one surface of the adhesive sheet 20 instead of the heat radiating plate 11. That is, one surface of the pressure-sensitive adhesive sheet 20 may be bonded to one of the heat radiating plate 11 and the organic EL display 12.

  In addition, although the 1st process which concerns on this embodiment has mentioned the processing method using the cut roller 51 by which the some circular blade 51b was provided in the rod-shaped member 51a with the predetermined space | interval W, it does not restrict to this. Absent. For example, a processing method that does not use a blade such as laser processing or water processing may be used.

(Second Embodiment)
Next, the configuration of the organic EL display device 2 according to the second embodiment of the present invention will be described with reference to FIG. FIG. 4A is a cross-sectional view taken along the line DD in FIG. FIG.4 (b) is the top view seen from the direction of CC line of Fig.4 (a). As shown in FIG. 4A and FIG. 4B, the organic EL display device 2 of the present embodiment includes an organic EL display 12, a heat radiating plate 11, and an adhesive sheet 30 having adhesiveness on both sides. Are bonded to each other at opposite positions. The organic EL display device 2 of the present embodiment is described above in that the plurality of grooves 30a are formed in a lattice shape in the adhesive sheet 30 and the groove depth D is the same as the thickness T of the adhesive sheet. This is different from the organic EL display device 1 described in the first embodiment. Since the other points are the same as in the first embodiment, the same elements as those in FIG.

  As shown in FIG. 4B, the adhesive sheet 20 is formed in a lattice shape so that a plurality of grooves 20 a intersect each other with a groove interval W. Moreover, the groove depth D is the same as the thickness T of the adhesive sheet.

(Method for manufacturing organic EL display device)
Next, a method for manufacturing the organic EL display device 2 according to this embodiment will be described. FIG. 5 and FIG. 6 are process diagrams showing the manufacturing method of the organic EL display device 2 in order. In the present embodiment, a first step of forming a plurality of grooves 30 a in the pressure-sensitive adhesive sheet 30, a step of bonding one surface of the pressure-sensitive adhesive sheet 30 to the radiator plate 11 after the first step, and a pressure-sensitive adhesive sheet 30 A second step of bonding the organic EL display 12 and the heat dissipation plate 11 together.

  When manufacturing the organic EL display device 2, first, as shown in FIG. 5A, a pressure-sensitive adhesive sheet 30 having conventional release sheets 31 and 32 on both sides is prepared. Thereby, in the 1st process mentioned below, a plurality of slots 30a can be formed in adhesive sheet 30 by using release sheet 32 as a ground. Next, as shown in FIG.5 (b), the peeling sheet 31 on the adhesive sheet 30 is peeled off. Thereby, the flat surface of the adhesive sheet 30 is exposed.

  Next, as shown in FIG.5 (c), the some groove | channel 30a is formed in the adhesive sheet 30 which has the peeling sheet 32 in the foundation | substrate. When forming the plurality of grooves 30a, for example, it is performed by pressing using a press die 52 in which a plurality of lattice-shaped blades 52b are provided on the plate-like member 52a with a predetermined interval W. A plurality of grooves 30 a are formed in the pressure-sensitive adhesive sheet 30 by pressing in the vertical direction (the arrow in FIG. 5C) with respect to the upper surface of the pressure-sensitive adhesive sheet 30 using the press die 52.

  As a result, as shown in FIG. 5 (d), the plurality of grooves 30a are formed in a lattice shape with a groove interval W therebetween so as to correspond to the predetermined interval W of the plurality of lattice-like blades 52b. The Here, when forming the plurality of grooves 30 a using the press die 52, the plurality of grid-like blades 52 b of the press die 52 penetrate the adhesive sheet 30 and reach the upper surface of the release sheet 32. Thereby, the some groove | channel 30 is formed so that the groove depth D may become the same as the thickness T of an adhesive sheet. By using the grid-shaped pattern press die 52, a plurality of grid-shaped grooves 30a can be formed in a lump.

  Next, as shown in FIG. 6A, a heat radiating plate 11 manufactured by a method similar to the conventional one is prepared. Next, the pressure-sensitive adhesive sheet 30 is reversed so that the release sheet 32 used as a base when the plurality of grooves 30a are formed faces up. Next, one surface of the adhesive sheet 30 is bonded to the upper surface of the heat sink 11. When one surface of the pressure-sensitive adhesive sheet 30 is bonded to the upper surface of the heat radiating plate 11, the pressure-sensitive adhesive sheet 30 is disposed so as to fit inside the heat radiating plate 11.

  Further, when the one surface of the pressure-sensitive adhesive sheet 30 is bonded to the upper surface of the heat radiating plate 11, the pressure roller 50 is used as in the first embodiment. A release sheet 32 is provided on the other surface (upper surface) of the pressure-sensitive adhesive sheet 30. When the pressure-sensitive adhesive sheet 30 is pressed using the pressure roller 50, the pressure roller 50 and the pressure-sensitive adhesive sheet 30 do not adhere to each other. It is like that.

  Since the adhesive sheet 30 is formed with a plurality of lattice-shaped grooves 30a, air bubbles are formed on the upper surface of the radiator plate 11 between the radiator plate 11 and the adhesive sheet 30 as shown in FIG. The adhesive sheet 30 is bonded without generating. Next, as shown in FIG.6 (c), the peeling sheet 32 on the adhesive sheet 30 is peeled off.

  Next, as shown in FIG.6 (d), the organic electroluminescent display 12 is bonded together on the upper surface of the adhesive sheet 30 bonded together by using the heat sink 11 as a base. Since the adhesive sheet 30 has a plurality of lattice-shaped grooves 30a, when the organic EL display 12 and the heat dissipation plate 11 having no flexibility are bonded together, The air that has entered flows smoothly and in a well-balanced manner along the plurality of grooves 30a. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and the organic EL display 12 and the heat sink 11 can be bonded together more reliably. Through the above steps, the organic EL display device 2 of the present embodiment can be manufactured.

  According to the method for manufacturing the organic EL display device 2 of the present embodiment, after the first step, there is a step of bonding one surface of the pressure-sensitive adhesive sheet 30 to the heat radiating plate 11. When attached, a plurality of grooves 30 a can be formed in the adhesive sheet 30 with the release sheet 32 as a base. Therefore, it is not necessary to prepare a new base substrate when forming the plurality of grooves 30a in the adhesive sheet 30, which is preferable in terms of productivity.

  Moreover, according to this manufacturing method, since the some groove | channel 30a is formed in a grid | lattice form, when bonding the organic EL display 12 and the heat sink 11 which are not flexible, the adhesive sheet 30, the organic EL display 12, and The air that has entered between flows smoothly with a good balance along the plurality of grooves 30a. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and the organic EL display 12 and the heat sink 11 can be bonded together more reliably.

  Further, according to the present manufacturing method, since the plurality of grooves 30a are formed by press working, the plurality of grooves 30a having a predetermined pattern are collectively formed by using the press mold 52 having a predetermined pattern. Therefore, productivity can be improved.

  In the organic EL display device 2 according to the present embodiment, the plurality of grooves 30a are formed in the lattice shape in the adhesive sheet 30, but the present invention is not limited thereto. For example, a plurality of grooves 40a may be radially formed in the adhesive sheet 40 as in the modification shown in FIG.

(Modification 1)
FIG. 7A is a schematic diagram showing a schematic configuration of the organic EL display device 3 of the first modified example according to the present embodiment, corresponding to FIG. The organic EL display device 3 of this modification is different from the organic EL display device 2 described in the second embodiment in that a plurality of grooves 40a are formed radially on the adhesive sheet 40. Since the other points are the same as in the second embodiment, the same elements as those in FIG. 4B are denoted by the same reference numerals, and detailed description thereof is omitted.

(Method for manufacturing organic EL display device)
FIG. 7B is a process diagram showing a manufacturing process of the organic EL display device 3 of the first modification example according to this embodiment corresponding to FIG. This process diagram shows a process of bonding the organic EL display 12 and the heat sink 11 via the adhesive sheet 40. Since other processes are the same as those of the second embodiment, detailed description thereof is omitted.

  As shown in FIG. 7B, the organic EL display 12 is bonded to the upper surface of the pressure-sensitive adhesive sheet 40 bonded with the radiator plate 11 as a base. The adhesive sheet 40 has a plurality of radial grooves 40a. When the non-flexible organic EL display 12 and the heat radiating plate 11 are bonded together, it is preferable that the organic EL display 12 be bonded so that the radial grooves 40a are spaced from the smaller side to the larger side. Thereby, the air that has entered between the pressure-sensitive adhesive sheet 40 and the organic EL display 12 flows smoothly and in a particularly well-balanced manner along the plurality of radial grooves 40a. For this reason, generation | occurrence | production of the bubble by the penetration | invasion of air can be suppressed markedly, and the organic EL display 12 and the heat sink 11 can be bonded together more reliably.

  The inventor of the present application conducted an experiment to verify the effect of the manufacturing method of the organic EL display device of the present invention. Specifically, in the step of bonding the organic EL display and the heat sink through the adhesive sheet, it can be determined whether or not bubbles remain (the presence or absence of bubbles) between the adhesive sheet and the organic EL display. The organic EL display and the heat radiating plate were each replaced with transparent glass, and an experiment was conducted to bond them together. Hereinafter, the experimental results will be described with reference to FIG.

  In this example, a bonded structure 1b shown in FIG. 8B was manufactured by bonding two transparent glasses to positions facing each other through an adhesive sheet in which a plurality of grooves were formed. Moreover, in the comparative example, the pasting shown in FIG. 8 (a) is performed by pasting two transparent glasses to positions facing each other through a conventional adhesive sheet having a plurality of flat surfaces on which a plurality of grooves are not formed. The laminated structure 1a was produced.

  And the presence or absence of the bubble between an adhesive sheet and transparent glass was confirmed about the bonding structure of a present Example and a comparative example. As shown in FIG. 8A, when the result of the comparative example is observed, the remaining bubbles are confirmed. The bubbles are spread left and right mainly with reference to the upper and lower sides of the bonded structure 1a. On the other hand, as shown in FIG. 8B, when the results of the present example are observed, no bubbles remain.

  That is, in the step of bonding the organic EL display and the heat dissipation plate through the adhesive sheet, the bubbles due to the intrusion of air are formed by bonding the adhesive sheet and the organic EL display through the adhesive sheet in which a plurality of grooves are formed. It has been found that it is possible to suppress the occurrence of bubbles so that no bubbles remain.

1, 2, 3 ... Organic EL display device (display device), 11 ... Heat sink, 12 ... Organic EL display (display panel), 20, 30, 40 ... Adhesive sheet, 20a, 30a, 40a ... Groove, W ... Groove Interval (predetermined interval), D ... groove depth (groove depth), T ... thickness of adhesive sheet

Claims (11)

In the manufacturing method of the display device, in which the display panel and the heat radiating plate are bonded to each other through an adhesive sheet having adhesiveness on both sides,
A first step of forming a plurality of grooves in the adhesive sheet;
A method of manufacturing a display device, comprising: a second step of bonding the display panel and the heat dissipation plate through the adhesive sheet after forming the plurality of grooves in the adhesive sheet.   The method for manufacturing a display device according to claim 1, further comprising a step of bonding one surface of the pressure-sensitive adhesive sheet to one of the heat radiating plate and the display panel before the first step.   2. The method for manufacturing a display device according to claim 1, further comprising a step of bonding one surface of the pressure-sensitive adhesive sheet to one of the heat radiating plate and the display panel after the first step.   The method for manufacturing a display device according to claim 1, wherein the plurality of grooves are formed so as to open to the outside at at least one end of the pressure-sensitive adhesive sheet.   5. The method of manufacturing a display device according to claim 1, wherein the plurality of grooves are formed so as to communicate from one end portion to the other end portion of the pressure-sensitive adhesive sheet.   The said some groove | channel is formed so that it may become in parallel with the perpendicular direction orthogonal to the normal line direction of one surface of the said display panel. Manufacturing method of display device.   The method for manufacturing a display device according to claim 1, wherein the plurality of grooves are formed to extend in parallel with each other at a predetermined interval.   The method for manufacturing a display device according to claim 1, wherein the plurality of grooves are formed in a lattice shape.   The method for manufacturing a display device according to claim 1, wherein the plurality of grooves are formed radially.   The method for manufacturing a display device according to claim 1, wherein the plurality of grooves are formed such that a depth of the plurality of grooves is smaller than a thickness of the pressure-sensitive adhesive sheet.   The method for manufacturing a display device according to claim 1, wherein the plurality of grooves are formed by press working.

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