Method for manufacturing a light-emitting display panel

Abstract

To make it possible to easily manufacture a light-emitting display panel in which distortion of a light-emitting image is suppressed, by making a step of smoothing a front (surface on which light-emitting modules are arranged) side of a base panel require less labor.SOLUTION: A method for manufacturing a light-emitting display panel that displays a light-emitting image by switching light-emitting states of a plurality of light-emitting modules 2 arranged two-dimensionally on a front of a base panel 1, smooths a front side of the base panel 1 by going through [1] a heat-shrinkable film covering step of covering the front side of the base panel 1 with a light-transmitting heat-shrinkable film 3 and fixing the heat-shrinkable film 3 to a periphery of the base panel 1, and [2] a heat-shrinkable film heating step of stretching the heat-shrinkable film 3 along the base panel 1 by heating and shrinking the heat-shrinkable film 3.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to an emissive display panel that displays an emissive image by switching the luminous state of a plurality of light-emitting modules that are two-dimensionally arranged, and a method for manufacturing the same. [Background technology]

[0002] Illuminated display panels that display luminous images by switching the light-emitting state of a plurality of light-emitting modules (such as LEDs) arranged two-dimensionally on a base panel have come to be widely used as electronic billboards for advertising, etc. Various types of luminous display panels have been proposed so far (see, for example, Patent Documents 1 and 2). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2003-255862 A [Patent Document 2] JP 2012-089806 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, an emissive display panel can only display emissive images when its power supply is turned on and the emissive module is emitting light. Illuminant display panels installed as digital signage are generally turned off during the hours when there are few people around, from late at night to early in the morning, during which time the emissive surface of the emissive display panel (the display surface that displays the emissive image) is completely dark. This leads to a loss of scenery.

[0005] In view of this situation, the applicant has come up with the idea of ​​overlaying a translucent panel on which a pattern is printed on the front surface (the surface on which the light-emitting modules are arranged) of a base panel. This makes it possible to visually recognize the pattern printed on the translucent panel when the light-emitting modules are not emitting light. This solves the above problem. On the other hand, when the light-emitting modules are emitting light, the light emitted from the light-emitting modules passes through the translucent panel, allowing a person looking at the display surface of the light-emitting display panel to visually recognize the luminous image (the display image resulting from the light emission of the light-emitting modules). At this time, the pattern printed on the translucent panel becomes almost invisible due to being overshadowed by the luminous image.

[0006] However, as described above, in a light-emitting display panel in which a light-transmitting panel with a printed pattern is overlaid on a base panel, the light-emitting image can appear distorted. This is because if the light-transmitting panel is warped even slightly, the warped portion acts as a pseudo lens, causing the light-emitting image that overlays that portion to be distorted, and it is very difficult to overlay and fix a light-transmitting panel on the light-emitting display panel in a completely flat state without any warping.

[0007] Therefore, in order to solve the above problem, the applicant further investigated the matter and came up with the idea of ​​pouring a transparent resin into the front surface of the base panel (the surface on which the light emitting modules are arranged) and solidifying it to smooth the front surface of the base panel (filling in the unevenness caused by the light emitting modules and the like with transparent resin to make it smooth), and then printing a pattern on the smooth surface. This makes it possible to suppress the distortion of the light emitting image caused by the pseudo lens described above.

[0008] However, the above-mentioned method of smoothing the front side of the base panel by pouring in a transparent resin and solidifying it requires a lot of work to pour in the transparent resin and smooth out the surface of the transparent resin. Also, with this method, the transparent resin is completely integrated into the base panel. Therefore, if the design (the design visible when the light-emitting module is not emitting light) is to be changed, the entire light-emitting display panel must be replaced.

[0009] The present invention has been made to solve the above-mentioned problems, and makes it possible to easily manufacture an emissive display panel with reduced distortion of the luminous image by eliminating the labor-intensive process of smoothing the front surface of the base panel (the surface on which the light-emitting modules are arranged). [Means for solving the problem]

[0010] The above issues are: A method for manufacturing an emissive display panel that displays an emissive image by switching the emissive states of a plurality of emissive modules that are two-dimensionally arranged on a front surface of a base panel, comprising: a heat-shrinkable film covering step of covering the front surface side of the base panel with a light-transmitting heat-shrinkable film and fixing the heat-shrinkable film to a periphery of the base panel; A heat shrink film heating process in which the heat shrink film is heated and shrunk so that the heat shrink film is stretched along the base panel. The method for manufacturing a light-emitting display panel is characterized in that the front surface side of the base panel is smoothed by passing through the steps of: This is solved by providing

[0011] As a result, even if the heat shrink film placed on the front side of the base panel in the heat shrink film covering process is loose or wrinkled, the heat shrink film will shrink and become taut on the front side of the base panel in the heat shrink film heating process carried out afterwards. Therefore, the front side of the base panel can be smoothed by the simple task of fixing the heat shrink film to the base panel and heating it. Therefore, it is possible to easily manufacture an emissive display panel with reduced distortion of the emissive image.

[0012] In the method for producing a light-emitting display panel of the present invention, it is preferable to carry out a background image printing step of printing a background image on the front surface side of the heat shrinkable film.

[0013] This allows the light-emitting image to be seen when the light-emitting module is emitting light, and the background image to be seen when the light-emitting module is not emitting light. This makes it possible to make the light-emitting display panel look stylish even when the power supply to the light-emitting display panel is turned off. In addition, when changing the background image, it is possible to change it by only replacing the heat shrink film. When the light-emitting module is emitting light, the background image is almost invisible because it is overshadowed by the light-emitting image.

[0014] In the method for producing the luminous display panel of the present invention, it is also preferable to carry out a buffer sheet covering step of covering the front surface side of the base panel with a light-transmitting buffer sheet prior to carrying out the heat shrink film covering step.

[0015] This is because if the corners of the light-emitting module come into contact with the heat-shrinkable film, the heat-shrinkable film may get caught on the corners when it is heated and shrunk, causing wrinkles to form in the heat-shrinkable film or causing the heat-shrinkable film to break. In this regard, by disposing a buffer sheet between the base panel and the heat-shrinkable film, it is possible to prevent the corners of the light-emitting module from directly coming into contact with the heat-shrinkable film. In addition, the buffer sheet can appropriately diffuse the light emitted from the light-emitting module, making the light-emitting image look beautiful.

[0016] The above issues are: A base panel and A plurality of light-emitting modules are arranged two-dimensionally on the front surface of the base panel. Equipped with An illuminating display panel that displays an illuminating image by switching the illuminating states of a plurality of light emitting modules, A light-emitting display panel in which the front surface side of the base panel is covered with a heat-shrinkable film and smoothed. This can also be solved by providing

[0017] In the light-emitting display panel of the present invention, A plurality of spacer protrusions are repeatedly formed two-dimensionally on the front surface of the base panel; The heat shrink film is placed on the tip surfaces of the plurality of spacer protrusions. It is preferred.

[0018] This is because if the heat shrink film is placed directly on the upper side of the light emitting module, the shrink force generated when the heat shrink film is heated and shrunk may be transmitted to the light emitting module, causing the light emitting module to shift in orientation or position, or in the worst case, causing the light emitting module to break off. In this regard, by providing the spacer protrusions as described above, it is possible to make it difficult for the shrink force of the heat shrink film to be transmitted to the light emitting module. In addition, by providing an appropriate gap between the light emitting module and the heat shrink film, it is also possible to appropriately diffuse the light emitted from the light emitting module in the gap. Effect of the Invention

[0019] As described above, the present invention makes it possible to easily manufacture an emissive display panel with reduced distortion of the luminous image by eliminating the labor-intensive process of smoothing the front surface of the base panel (the surface on which the luminous modules are arranged). [Brief description of the drawings]

[0020] [Figure 1] 1 is a perspective view showing an entire emissive display panel according to a first embodiment; [Diagram 2] FIG. 2 is an exploded perspective view of the emissive display panel of the first embodiment. [Diagram 3] 1 is a cross-sectional view showing the emissive display panel of the first embodiment cut along a plane perpendicular to the y-axis. [Figure 4] 1 is a perspective view showing the luminous display panel of the first embodiment when a luminous image is not displayed (when a background image is displayed). FIG. [Diagram 5] FIG. 11 is a perspective view showing the entire emissive display panel of the second embodiment. [Figure 6] FIG. 11 is an exploded perspective view of a light-emitting display panel according to a second embodiment. [Figure 7] 11 is a cross-sectional view showing a state in which the emissive display panel of the second embodiment is cut along a plane perpendicular to the y-axis. FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0021] A preferred embodiment of the luminous display panel of the present invention will be described in more detail with reference to the drawings. In the following, the luminous display panel of the present invention will be described using two embodiments (first and second embodiments) as examples, but the technical scope of the luminous display panel of the present invention is not limited to these embodiments. The luminous display panel of the present invention and its manufacturing method can be modified as appropriate within the scope of the invention.

[0022] 1. First embodiment of the emissive display panel First, the luminous display panel of the first embodiment will be described. FIG. 1 is a perspective view showing the entire luminous display panel of the first embodiment. FIG. 2 is an exploded perspective view of the luminous display panel of the first embodiment. FIG. 3 is a cross-sectional view showing the luminous display panel of the first embodiment cut along a plane perpendicular to the y-axis. FIG. 4 is a perspective view showing the luminous display panel of the first embodiment when the luminous image is not displayed (when the background image α is displayed). FIGS. 1 to 4 show an orthogonal coordinate system consisting of an x-axis, a y-axis, and a z-axis. The directions of the x-axis, the y-axis, and the z-axis are common to different drawings.

[0023] 1.1 Structure of the emissive display panel according to the first embodiment As shown in FIG. 1, the light-emitting display panel of the first embodiment is a panel-shaped display device, and displays a light-emitting image on its front surface (the surface facing the z-axis direction positive side; the same applies below). This light-emitting display panel can be suitably used as an electronic signboard for advertising on street corners, in store parking lots, on the side of the road, etc. It can also be suitably used as an electronic display board for displaying traffic congestion information, etc. on roads. It can also be suitably used as an electronic guide board for providing information on departure times, flight times, etc. at transportation facilities such as stations and airports. It can also be suitably used as a large screen for displaying game progress, replay images, etc. in stadiums, etc. The light-emitting images displayed on the light-emitting display panel include not only still images but also videos.

[0024] As shown in FIG. 2, the light-emitting display panel of the first embodiment is composed of a base panel 1, a plurality of light-emitting modules 2, a heat-shrinkable film 3, and a buffer sheet 4. The light-emitting element modules 2 are arranged two-dimensionally (in the x-axis and y-axis directions) on the front surface (the surface facing the z-axis direction positive side; the same applies below) of the base panel 1. By controlling the light-emitting state of each light-emitting module 2, a predetermined light-emitting image can be displayed on the front surface (more precisely, the front surface 3a of the heat-shrinkable film 3) of the light-emitting display panel. The buffer sheet 4 and the heat-shrinkable film 3 are superimposed on the upper side (the z-axis direction positive side) of the light-emitting module 2. Both the buffer sheet 4 and the heat-shrinkable film 3 are translucent, so that the light-emitting image produced by the light emitted from the light-emitting module 2 passes through the buffer sheet 4 and the heat-shrinkable film 3 and is displayed on the front surface 3a of the heat-shrinkable film 3.

[0025] Light-emitting elements such as light-emitting diodes (LEDs) are normally used for the light-emitting modules 2. In the light-emitting display panel of the first embodiment, a full-color LED module that combines three colors of LEDs, namely red LEDs, green LEDs, and blue LEDs and allows the light output of each LED to be controlled, is used as each light-emitting module 2. This allows the light-emitting image displayed on the front surface 3a of the heat-shrinkable film 3 to be a full-color image. A power supply, wiring, and the like (not shown) that supplies power to the light-emitting modules 2 are provided on the back side of the base panel 1.

[0026] A background image α (FIG. 4) is printed on the heat shrink film 3 covering the front side of the base panel 1. In the example shown in FIG. 4, a brick pattern is displayed as the background image α, but other than this, a tile pattern, a wood grain pattern, or a plain pattern (including a gradation pattern) can also be displayed. Furthermore, photographs of landscapes, people, products, etc., illustrations of characters or products, letters or symbols showing product names, company names, etc., and guide signs showing "emergency exits" or "evacuation sites" can also be displayed as the background image α.

[0027] When the light-emitting module 2 (FIG. 2) is illuminated to display a luminous image (when the luminous image is displayed), this background image α is barely visible due to the luminous image, but when the light-emitting module 2 is not illuminated and a luminous image is not displayed (when the luminous image is not displayed), the background image α is visible. In other words, when the luminous image is not displayed, the background image α is displayed as shown in FIG. 4, so that the display surface of the luminous display panel does not become pitch black.

[0028] Therefore, in the luminous display panel of the first embodiment, the display surface can be made to look stylish when the luminous image is not displayed. In addition, the display surface can be used for advertising and guidance when the luminous image is not displayed. Furthermore, when the luminous display panel is installed on the wall of a building, the background image α can be made to have the same color and pattern as the wall of the building, so that the luminous display panel when the luminous image is not displayed can be made to blend in with the surrounding wall and become less noticeable.

[0029] 1.2 Manufacturing method of the emissive display panel of the first embodiment In this way, the luminous display panel of the first embodiment is capable of displaying the background image α even when the luminous image is not displayed, and can be devised in various ways that take into consideration the installation location, scenery, etc. This luminous display panel is manufactured through a buffer sheet covering process, a heat shrink film covering process, a heat shrink film heating process, and a background image printing process.

[0030] 1.2.1 Buffer sheet covering process As shown in FIG. 2, the buffer sheet covering step is a step of covering the front surface (the surface facing the positive side in the z-axis direction) of the base panel 1 with a buffer sheet 4. A light-transmitting sheet is used for the buffer sheet 4 so that the light-emitting image by the light-emitting module 2 is not blocked by the buffer sheet 4. In the luminous display panel of the first embodiment, a thin nonwoven fabric sheet is used as the buffer sheet 4. This buffer sheet 4 prevents the heat-shrinkable film 3, which will be described later, from directly contacting the base panel 1, the light-emitting module 2, etc. Also, the light emitted from the light-emitting module 2 can be appropriately diffused by the buffer sheet 4, making the light-emitting image look beautiful.

[0031] 1.2.2 Heat shrink film covering process After the buffer sheet covering step is completed, a heat shrink film covering step is performed. The heat shrink film covering step is a step of covering the front surface side of the base panel 1 with a heat shrink film 3, as shown in FIG. 2. The periphery of the heat shrink film 3 is fixed to the periphery of the base panel 1 (the side end surface of the base panel 1). A light-transmitting sheet is used for the heat shrink film 3 so that the light-emitting image by the light-emitting module 2 is not blocked by the heat shrink film 3. The heat shrink film 3 may be translucent or the like, but is usually transparent. This heat shrink film 3 is shrunk by a heat shrink film heating step described later, and is stretched along the front surface of the base panel 1.

[0032] The front surface of the base panel 1 has unevenness due to the arrangement of the light-emitting modules 2 (where the light-emitting modules 2 are located, they form convex portions, and the gaps between adjacent light-emitting modules 2 form concave portions), but by attaching a heat-shrinkable film 3 to the front surface of the base panel 1, it is possible to smooth the front surface of the base panel 1. This makes it possible to display the background image α (Figure 4) clearly and easily on the front surface of the base panel 1 (front surface of the light-emitting display panel). It is also possible to clearly project the light-emitting image produced by the light-emitting modules 2 onto the display surface (front surface) of the light-emitting display panel.

[0033] There are no particular limitations on the heat shrinkable film 3 as long as it shrinks (thermally shrinks) when heated. Examples of the heat shrinkable film 3 include polyolefin-based films, polyethylene-based films, polystyrene-based films, polyvinyl chloride-based films, and polyethylene terephthalate-based films.

[0034] Among them, polyolefin-based films have the drawback of being somewhat expensive, but have the advantages of [1] high shrinkage rate and good finish (less prone to wrinkles, etc.), [2] excellent puncture resistance, [3] high tear strength, and [4] the ability to shrink at a relatively low temperature without applying excess heat to the underlying light-emitting module 2, etc., and therefore can be suitably used as the heat-shrinkable film 3. A polyolefin-based film is also used as the heat-shrinkable film 3 in the light-emitting display panel of the first embodiment.

[0035] The heat shrinkage rate of the heat shrink film 3 is not particularly limited. However, if the heat shrinkage rate of the heat shrink film 3 is small, the heat shrink film 3 may not shrink as expected even when the heat shrink film heating step described later is performed, and wrinkles or the like may remain on the heat shrink film 3 after heating. For this reason, it is preferable to use a heat shrink film 3 having a heat shrinkage rate (shrinkage rate (%) measured in accordance with JIS-Z-1709; the same applies below) of 30% or more. The heat shrinkage rate of the heat shrink film 3 is more preferably 40% or more, and even more preferably 50% or more. There is no particular upper limit to the heat shrinkage rate of the heat shrink film 3, but it is usually up to about 70 to 80%. In the light-emitting display panel of the first embodiment, the heat shrinkage rate of the heat shrink film 3 is about 58 to 60%.

[0036] The thickness of the heat shrinkable film 3 is not particularly limited. However, if the heat shrinkable film 3 is too thin, the strength of the heat shrinkable film 3 decreases, and the puncture resistance and tear strength of the heat shrinkable film 3 cannot be maintained. For this reason, the thickness of the heat shrinkable film 3 is preferably 5 μm or more. The thickness of the heat shrinkable film 3 is more preferably 10 μm or more, and even more preferably 13 μm or more. However, if the heat shrinkable film 3 is too thick, the heat shrinkable film 3 may not easily shrink. For this reason, the thickness of the heat shrinkable film 3 is usually 500 μm or less. The thickness of the heat shrinkable film 3 is more preferably 100 μm or less, and even more preferably 50 μm or less. In the light-emitting display panel of the first embodiment, the thickness of the heat shrinkable film 3 is about 15 μm.

[0037] As already described, the heat shrink film 3 is fixed to the periphery of the base panel 1. This allows the heat shrink film 3 to be tensioned and kept taut when the heat shrink film 3 is heated and shrunk in a heat shrink film heating step described later. The method of fixing the heat shrink film 3 to the periphery of the base panel 1 is not particularly limited. In the light-emitting display panel of the first embodiment, as shown in FIG. 2, a double-sided adhesive tape 5 is attached along the side end surface of the base panel 1, and the heat shrink film 3 is adhered to the outer adhesive surface of the double-sided adhesive tape 5.

[0038] The double-sided adhesive tape 5 may be provided intermittently on the side end surface of the base panel 1, but in this case, the tension applied to the vicinity of the periphery of the heat shrinkable film 3 may become uneven, and wrinkles or the like may easily form near the periphery of the heat shrinkable film 3. For this reason, in the luminous display panel of the first embodiment, the double-sided adhesive tape 5 is provided continuously and seamlessly on the side end surface of the base panel 1.

[0039] To ensure a portion that will adhere to the double-sided adhesive tape 5 (a portion that will cover the side end face of the base panel 1), the heat shrink film 3 is cut to a size slightly larger than the front surface of the base panel 1. After the heat shrink film 3 is attached to the side end face of the base panel 1, it is preferable to cut off the portion of the heat shrink film 3 that protrudes beyond the double-sided adhesive tape 5 with a cutter, scissors, or the like. This can improve the appearance of the luminous display panel.

[0040] 1.2.3 Heat shrink film heating process After the heat shrink film covering step is completed, a heat shrink film heating step is performed. As shown in Fig. 3, the heat shrink film heating step is a step of heating and shrinking the heat shrink film 3 attached to the front surface side of the base panel 1. Even if wrinkles or the like are formed on the heat shrink film 3 immediately after the heat shrink film covering step, the heat shrink film 3 can be shrunk by this heat shrink film heating step, and the heat shrink film 3 can be stretched along the base panel 1. In other words, the front surface side of the base panel 1 can be smoothed.

[0041] In the heat shrink film heating step, the method of heating the heat shrink film 3 is not particularly limited. However, if the entire light-emitting display panel is heated, there is a risk of damaging the light-emitting module 2 and the wiring and electronic boards (not shown) provided on the back side of the base panel 1. For this reason, it is preferable to heat the heat shrink film 3 by blowing hot air onto the front surface side of the base panel 1 (the front surface 3a side of the heat shrink film 3). This makes it possible to make the light-emitting module 2 and the like located below the heat shrink film 3 (the negative side in the z-axis direction) less susceptible to damage from heat.

[0042] In the light-emitting display panel of the first embodiment, hot air is blown onto the front surface side (front surface 3a side of heat-shrinkable film 3) of base panel 1 using a dryer (heating gun) to heat heat-shrinkable film 3. The amount of hot air that is blown onto heat-shrinkable film 3 is not particularly limited, but is usually 0.15 to 0.25 m 3 It is said to be about / minute.

[0043] The temperature of the hot air blown onto the heat shrink film 3 (hereinafter referred to as the "heating temperature of the heat shrink film 3") varies depending on the type of heat shrink film 3, and is not particularly limited. However, if the heating temperature of the heat shrink film 3 is too low, the heat shrink film 3 may not heat shrink as expected. This problem can be solved by using a heat shrink film 3 that heat shrinks even at a low temperature.

[0044] However, in this case, when the light-emitting display panel is in use, the heat from the light-emitting module 2 (even when an LED is used as the light-emitting module 2, the light-emitting module 2 will heat up to about 40°C) or heat from the sun may cause the heat-shrinkable film 3 to shrink. For this reason, it is preferable to use a heat-shrinkable film 3 that does not shrink at heat of about 40 to 50°C, and to set the heating temperature of the heat-shrinkable film 3 in the heat-shrinkable film heating step to a temperature higher than this. The heating temperature of the heat-shrinkable film 3 is preferably 80°C or higher, more preferably 90°C or higher, and even more preferably 100°C or higher.

[0045] However, if the heating temperature of the heat shrink film 3 is too high, there is a risk of damaging the light emitting module 2 and the wiring and electronic boards (not shown) provided on the back side of the base panel 1. For this reason, it is also not good to heat the heat shrink film 3 too high. The heating temperature of the heat shrink film 3 is preferably 200°C or less, more preferably 170°C or less, and even more preferably 150°C or less. In the light emitting display panel of the first embodiment, the heating temperature of the heat shrink film 3 is set to about 100 to 120°C.

[0046] The heat shrink film 3 is heated until the heat shrink film 3 is taut and wrinkles etc. are removed. When the heat shrink film 3 is in a nicely taut state, the heat shrink film heating step is completed.

[0047] 1.2.4 Background image printing process After the heat shrink film heating step is completed, a background image printing step is subsequently performed. The background image printing step is a step of printing a background image α (a brick pattern in the example shown in FIG. 4) on the front side of the heat shrink film 3, as shown in FIG. 4. This allows the background image α to be displayed on the display surface of the emissive display panel when in a non-emissive state (the emissive display panel when not displaying a luminous image). When the background printing step is performed, the heat shrink film 3 is in a taut state on the front side of the base panel 1 after the heat shrink film heating step, so that the background image α can be neatly printed on the front side of the heat shrink film 3.

[0048] As already mentioned, the background image α can represent not only brick patterns, but also tile patterns, wood grain patterns, solid patterns (including gradation patterns), photographs of landscapes, people, products, etc., illustrations of characters or products, letters or symbols representing product names, company names, etc., and signs directing people to "emergency exits" or "evacuation shelters," etc.

[0049] The method of printing the background image α on the heat shrinkable film 3 is not particularly limited. Examples of the method of printing the background image α include inkjet printing, screen printing, and thermal transfer printing. However, printing that heats the heat shrinkable film 3, such as thermal transfer printing, may cause the heat shrinkable film 3 to unintentionally thermally shrink. For this reason, it is preferable to adopt inkjet printing or screen printing as the method of printing the background image α. In the light-emitting display panel of the first embodiment, the background image α is printed by inkjet printing. Inkjet printing allows for high-resolution printing. In addition, since it is possible to apply ink thickly, it is also possible to form minute irregularities in the background image α.

[0050] 2. Second embodiment of the emissive display panel Next, the luminous display panel of the second embodiment will be described. The luminous display panel of the second embodiment will be described mainly focusing on the configuration different from the luminous display panel of the first embodiment (FIGS. 1 to 4) described above. For the configuration of the luminous display panel of the second embodiment that is not specifically mentioned, the same configuration as that described for the luminous display panel of the first embodiment can be adopted.

[0051] Fig. 5 is a perspective view showing the entire emissive display panel of the second embodiment. Fig. 6 is an exploded perspective view of the emissive display panel of the second embodiment. Fig. 7 is a cross-sectional view showing the emissive display panel of the second embodiment cut along a plane perpendicular to the y-axis. Figs. 5 and 6 show an orthogonal coordinate system consisting of an x-axis, a y-axis, and a z-axis. The directions of the x-axis, the y-axis, and the z-axis are common to different drawings.

[0052] In the light-emitting display panel of the first embodiment described above, as shown in Fig. 2, nothing other than the light-emitting module 2 is attached to the front surface (the surface facing the z-axis direction positive side) of the base panel 1, and the portion of the front surface of the base panel 1 where the light-emitting module 2 is not arranged is flat. For this reason, as shown in Fig. 3, the buffer sheet 4 and the heat-shrinkable film 3 are directly placed on the light-emitting module 2. Therefore, when the heat-shrinkable film 3 is heated in the heat-shrinkable film heating step, the shrinkage force of the heat-shrinkable film 3 is transmitted to the light-emitting module 2, which may cause the light-emitting module 2 to shift in orientation or position, or may cause the light-emitting module to break off.

[0053] In contrast, in the light-emitting display panel of the second embodiment, as shown in Fig. 6, spacer convex portions 1a are formed on the front surface (surface facing the z-axis direction positive side) of the base panel 1. The spacer convex portions 1a are formed two-dimensionally and repeatedly in the gaps between adjacent light-emitting modules 2. The tip surface (end surface facing the z-axis direction positive side) of the spacer convex portion 1a protrudes higher toward the front side (the z-axis direction positive side) than the light-emitting surface (surface facing the z-axis direction positive side) of the light-emitting module 2. The height of each spacer convex portion 1a is all uniform.

[0054] For this reason, in the light-emitting display panel of the second embodiment, as shown in FIG. 7, the buffer sheet 4 and the heat-shrinkable film 3 are placed on the tip surface of the spacer convex portion 1a, not on the light-emitting surface of the light-emitting module 2. Therefore, when the heat-shrinkable film 3 is heated in the heat-shrinkable film heating process, the contraction force of the heat-shrinkable film 3 is not transmitted to the light-emitting module 2. This makes it possible to suppress deviation in the orientation and position of the light-emitting module 2 when the heat-shrinkable film 3 thermally shrinks. In addition, by forming a gap β on the light-emitting surface side of the light-emitting module 2, it is also possible to make it difficult for the heat of the hot air applied to the heat-shrinkable film 3 to be transmitted to the light-emitting module 2. In addition, the gap β allows the light emitted from the light-emitting module 2 to be appropriately diffused, making the light-emitting image look beautiful.

[0055] 3.Other In the luminous display panel of the first embodiment and the luminous display panel of the second embodiment described above, the background image α is provided by printing, but the background image α can also be provided by a method other than printing. For example, the background image α can also be handwritten. Also, in the luminous display panel of the first embodiment and the luminous display panel of the second embodiment, the background image α is represented on the heat shrinkable film 3, but the background image α can also be represented on something other than the heat shrinkable film 3. For example, the background image α can also be represented on the front surface 4a or back surface 4b of the buffer sheet 4. [Explanation of symbols]

[0056] 1 Base Panel 1a Spacer protrusion 2 Light Emitting Module 3. Heat shrink film 3a Front side of heat shrink film (display side) 3b Back side of heat shrink film 4. Cushioning Sheet 4a Front side of the cushioning sheet 4b Back side of the cushioning sheet 5 Double-sided adhesive tape Alpha background image β Gap

Claims

1. A method for manufacturing an emissive display panel that displays an emissive image by switching the emissive states of a plurality of emissive modules that are two-dimensionally arranged on a front surface of a base panel, comprising: a heat-shrinkable film covering step of covering the front surface side of the base panel with a light-transmitting heat-shrinkable film and fixing the heat-shrinkable film to a periphery of the base panel; A heat shrink film heating process in which the heat shrink film is heated and shrunk so that the heat shrink film is stretched along the base panel.

3. A method for manufacturing a light-emitting display panel, comprising the steps of: smoothing the front surface side of the base panel through a process comprising the steps of:

2. 2. The method for producing a light-emitting display panel according to claim 1, further comprising a background image printing step of printing a background image on the front surface side of the heat shrinkable film.

3. 3. The method for manufacturing a light-emitting display panel according to claim 1, further comprising the step of: covering the front surface side of the base panel with a light-transmitting buffer sheet prior to the step of covering with the heat-shrinkable film.

Images