Method of manufacturing display device for vehicle, display panel for vehicle, and display device for vehicle

Abstract

To provide a display panel for a vehicle with which it is possible to reduce leakage of light without compromising the strength and aesthetic appearance of the display panel for the vehicle and without generating abnormal noise in the display panel for the vehicle, and a display device for a vehicle that comprises the display panel for the vehicle.SOLUTION: In a groove formation step, a groove 23 is formed between display areas AR11, AR12 for performing display with light transmitted from a back side BS to a front side FS of a transparent resin molded body 21 and an end part 21E of the transparent resin molded body 21, and / or between the mutually adjacent display areas AR11, AR12, by cutting processing using computer numerical control along a prescribed shape so as to leave a thickness TH1 in a prescribed range. In a filling body formation step, the groove is filled with a colored resin that blocks light traveling in the transparent resin molded body 21, and a colored resin filling body 22 is formed in the groove.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a method for manufacturing an automotive display device, an automotive display panel, and an automotive display device. [Background technology]

[0002] An automobile's instrument panel is provided with a display device. The display device of the instrument panel includes, for example, a display of a navigation system as described in Patent Document 1 (Japanese Patent No. 7125713) and an icon on a heater control panel. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7125713 Summary of the Invention [Problem to be solved by the invention]

[0004] In an automobile display device, light propagates through the transparent resin molding of the automobile display panel and the heater control panel, and may leak from, for example, an end of the transparent resin molding. If light leaks from an end of the automobile display panel or the heater control panel inside a car at night, the leaked light is very noticeable. In order to reduce the leakage of light from the end of such a transparent resin molded body, it is possible to provide a means for blocking light at the location where the light leaks. However, if the shape of the transparent resin molded body is made complex in order to provide a means for blocking light, the surface of the transparent resin molded body of the automotive display panel may be spoiled by sink marks after molding. If the surface defect of the transparent resin molded body spoils the aesthetic appearance, the automotive display panel may become a defective product because it is located in front of the driver and passengers. In addition, since there is a high possibility that the driver or passengers will collide with the instrument panel in a traffic accident, etc., the automotive display panel arranged in the instrument panel is expected to contribute to protecting the driver and passengers in an emergency such as an accident. Furthermore, it is required to suppress the deterioration of the strength of the automotive display panel and the generation of abnormal noise caused by each part rubbing against each other.

[0005] The objective of the present invention is to provide an automotive display panel that does not reduce the strength and aesthetics of the automotive display panel, does not generate abnormal noise in the automotive display panel, and reduces light leakage, and an automotive display device equipped with such an automotive display panel. [Means for solving the problem]

[0006] In the following, several aspects will be described as means for solving the problems. These aspects can be arbitrarily combined as necessary. A manufacturing method of an automobile display device according to a first aspect of the present invention includes an injection molding step, a groove forming step, and a filler forming step. In the injection molding step, a transparent resin molded body having a predetermined shape and transmitting light is injection molded. In the groove forming step, a groove is formed by cutting using computer numerical control along a predetermined shape so as to leave a predetermined thickness between a display area where display is performed using light transmitted from the back surface to the front surface of the transparent resin molded body and an end of the transparent resin molded body, and / or between adjacent display areas. In the filler forming step, a colored resin that blocks light traveling through the transparent resin molded body is filled into the groove to form a colored resin filler in the groove. The manufacturing method of the first aspect of the automotive display device includes a groove forming step and a filler forming step, and therefore the groove does not need to be formed by injection molding, and therefore sink marks and warping during the formation of the groove can be prevented. In addition, the groove is filled with a colored resin to form a colored resin filler in the groove, so that the transparent resin molded body around the groove is integrated with the colored resin filler and the transparent resin molded body is reinforced by the colored resin filler, and the reduction in strength of the automotive display panel due to the formation of the groove is suppressed, and the generation of abnormal noise in the automotive display panel due to the vibration of the automobile can be prevented. The colored resin filler in the groove can reduce light leaking to the edge of the transparent resin molded body and / or to adjacent display areas.

[0007] A manufacturing method for an automotive display device according to a second aspect of the present invention is configured in such a way that, in the manufacturing method for an automotive display device according to the first aspect, the specified range is 0.5 mm or more and 2 mm or less, and is half or less of the thickness of the transparent resin molding on both sides of the groove. According to the manufacturing method of the second aspect of the invention, it is possible to appropriately adjust the reduction of light leakage and the suppression of a decrease in strength of the automotive display panel.

[0008] A manufacturing method for an automotive display device according to a third aspect of the present invention is the manufacturing method for an automotive display device according to the first or second aspect, further comprising a thinning step of processing a display area of ​​a transparent resin molded body into a thin shape according to a predetermined shape by cutting using computer numerical control. According to the manufacturing method of the third aspect of the present invention, the difficulty of molding due to the fluidity of resin, such as in injection molding, is eliminated, making molding easier. In addition, by thinning the display area by cutting using computer numerical control, the difficulty of molding due to the fluidity of resin is eliminated, and the occurrence of sink marks and warping in the display area can be prevented.

[0009] A manufacturing method for an automotive display device according to a fourth aspect of the present invention includes, in the manufacturing method for an automotive display device according to the third aspect, a lamination step of laminating a display to a portion that has been thinned by cutting in the thinning step using an optically transparent resin or an optically transparent adhesive. According to the fourth aspect of the manufacturing method for an automotive display device, the visibility of the display can be improved by attaching an optically transparent resin or an optically transparent adhesive to a portion of the transparent resin molding that has been thinned by cutting.

[0010] A manufacturing method for an automotive display device according to a fifth aspect of the present invention is configured in such a way that, in the manufacturing method for an automotive display device according to the fourth aspect, the refractive index of the optical transparent resin or the optical transparent adhesive is not less than a value obtained by subtracting 0.1 from the refractive index of the transparent resin molding and is not more than a value obtained by adding 0.1 to the refractive index of the transparent resin molding. According to the fifth aspect of the manufacturing method for an automotive display device, the refractive index of the optical transparent resin or the optical transparent adhesive is set to a value equal to or greater than the refractive index of the transparent resin molding 21 minus 0.1 and equal to or less than the refractive index of the transparent resin molding 21 plus 0.1, thereby improving the visibility of the display compared to when the refractive index is set outside this range.

[0011] A sixth aspect of the present invention provides an automobile display panel, comprising: a transparent resin molded body having a predetermined shape and a groove formed by cutting along the predetermined shape, and a colored resin filler made of a colored resin that fills the groove and blocks light traveling through the transparent resin molded body. The transparent resin molded body has a display area that displays with light transmitted from the back surface to the front surface. The groove is disposed between the display area and an end of the transparent resin molded body and / or between adjacent display areas. The thickness of the transparent resin molded body at the groove is 0.5 mm or more and 2 mm or less, and is half or less of the thickness of the transparent resin molded body on both sides of the groove. In the sixth embodiment, the grooves are formed by cutting, so that sink marks and warping during the formation of the grooves can be prevented. In addition, the grooves are filled with colored resin to form a colored resin filler in the grooves, so that the transparent resin molding around the grooves is integrated with the colored resin filler, and the transparent resin molding is reinforced by the colored resin filler, so that the reduction in strength of the automotive display panel due to the formation of the grooves is suppressed, and abnormal noises due to the vibration of the automobile can be prevented from occurring in the automotive display panel. The colored resin filler in the grooves can reduce light leaking to the end of the transparent resin molding and / or to the adjacent display areas. In addition, the reduction in light leakage and the suppression of the reduction in strength of the automotive display panel can be appropriately adjusted. An automobile display panel according to a seventh aspect of the present invention is the automobile display panel according to the sixth aspect, wherein the transparent resin molding has a display region that is thinner than the periphery of the display region due to cutting work. According to the seventh aspect of the automotive display panel, it is possible to prevent sink marks and warping from occurring in the display area, and to provide the display area with a good aesthetic appearance.

[0012] An automobile display device according to an eighth aspect of the present invention comprises a transparent resin molded body having a predetermined shape and a groove formed by cutting along the predetermined shape and transmitting light, a colored resin filler made of a colored resin that fills the groove and blocks light traveling through the transparent resin molded body, and a light source that is arranged on the back surface side of the transparent resin molded body and emits light that transmits through the transparent resin molded body. The transparent resin molded body has a display area that displays with light that transmits from the back surface to the front surface. The groove is arranged between the display area and an end of the transparent resin molded body and / or between adjacent display areas. The thickness of the groove part of the transparent resin molded body is 0.5 mm or more and 2 mm or less, and is half or less of the thickness of the transparent resin molded body on both sides of the groove. In the eighth aspect of the automotive display device, the groove is formed by cutting, so that sink marks and warping during the formation of the groove can be prevented. In addition, the groove is filled with a colored resin to form a colored resin filler in the groove, so that the transparent resin molded body around the groove is integrated with the colored resin filler and the transparent resin molded body is reinforced by the colored resin filler, and the reduction in strength of the automotive display device due to the formation of the groove is suppressed, and the generation of abnormal noise in the automotive display device due to the vibration of the automobile can be prevented. The colored resin filler in the groove can reduce light leaking to the end of the transparent resin molded body and / or to the display areas adjacent to each other. In addition, the reduction in light leakage and the suppression of the reduction in strength of the automotive display device can be appropriately adjusted. A ninth aspect of the present invention relates to an automobile display device according to the eighth aspect, and the transparent resin molding is provided with an optically transparent resin or an optically transparent adhesive for bonding a display that displays using a light source to the thin portion of the display area. According to the ninth aspect of the present invention, the display device for an automobile can prevent sink marks and warping from occurring in the display area, and can provide a good appearance to the display area. Also, the optical transparent resin or the optical transparent adhesive that is bonded to the part of the transparent resin molded body that has been thinned by cutting can improve the visibility of the display. Effect of the Invention

[0013] According to the manufacturing method of the display device for automobiles of the present invention, it is possible to provide a display device for automobiles that does not deteriorate the strength and aesthetics of the display panel for automobiles, does not generate abnormal noise in the display panel for automobiles, and reduces light leakage in the display panel for automobiles. According to the display panel for automobiles or the display device for automobiles of the present invention, it is possible to reduce light leakage while preventing deterioration of the strength and aesthetics and generation of abnormal noise. [Brief description of the drawings]

[0014] [Figure 1]FIG. 2 is a schematic front view of an instrument panel for explaining the arrangement of an automobile display device in the instrument panel; [Diagram 2] 1 is a perspective view showing an example of a configuration of an automobile display panel according to a first embodiment. [Diagram 3] 3 is a cross-sectional view of the automobile display panel taken along line II in FIG. 2. [Figure 4] 2. FIG. 3 is a cross-sectional view of the automobile display panel taken along line II-II in FIG. [Diagram 5] 4 is a flowchart showing an example of a manufacturing flow of the display device for an automobile according to the first embodiment. [Figure 6] FIG. 11 is a cross-sectional view showing an example of a configuration of an automotive display panel according to a second embodiment. [Figure 7] FIG. 11 is a cross-sectional view showing an example of a configuration of an automotive display panel according to a third embodiment. [Figure 8] 10 is a flowchart showing an example of a manufacturing flow of the display device for an automobile according to the third embodiment. [Figure 9] FIG. 11 is a cross-sectional view showing an example of a configuration of an automotive display panel according to a fourth embodiment. [Figure 10] FIG. 11 is a cross-sectional view showing an example of the configuration of an automotive display panel according to a fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0015] First Embodiment (1) Configuration of Automotive Display Devices 1 shows an instrument panel 10 of an automobile. Meters such as a speedometer 11 are mounted on the instrument panel 10. The instrument panel 10 also includes a dashboard 12. A steering wheel 90 is disposed in front of the instrument panel 10. An automobile display panel 20 is disposed in the center of the instrument panel 10. The automobile display panel 20 is, for example, a part of a navigation system. A heater control panel 30 is disposed below the automobile display panel 20. When controlling cooling, the term "air conditioning control panel" may be used instead of the term "heater control panel". The heater control panel 30 displays, for example, a temperature setting icon, a heater symbol, a mode switching icon, and a power icon. The temperature setting icon is, for example, an icon showing a number or an arrow indicating a temperature. The heater symbol is a symbol represented by a wavy line design. The heater symbol indicates, for example, that the heater is operating. The mode switching icon is an icon indicating switching of the heater mode (heating, cooling, fan). The power icon is an icon indicating whether the heater is powered on or off.

[0016] (1-1) Automotive display panel An example of an automobile display panel 20 is shown in Fig. 2. The automobile display panel 20 includes a transparent resin molded body 21 and a colored resin filler 22 shown in Fig. 3 and Fig. 4. Fig. 3 shows a cross-sectional shape cut along line II in Fig. 2, and Fig. 4 shows a cross-sectional shape cut along line II-II in Fig. 2. In the center of the automotive display panel 20, a trapezoidal transparent first display area AR11 of a transparent resin molding 21 is disposed when viewed from the front, and a substantially rectangular second display area AR12 and a third display area AR13 are disposed below the first display area AR11. An opening 25 in which, for example, a knob is disposed is disposed between the second display area AR12 and the third display area AR13. When viewed from the front, a light-shielding area AR2 that does not transmit light is disposed around the display areas AR11, AR12, and AR13. The transparent resin molding 21 has a predetermined shape. Here, the predetermined shape is a rectangle when viewed from the front, a cross section curved in an arch shape, and a shape having an opening 25. The transparent resin molding 21 has a groove 23 formed by cutting. The groove 23 follows the predetermined shape of the transparent resin molding 21. In other words, the groove 23 shown in FIG. 3 and FIG. 4 is curved in an arch shape along the surface of the transparent resin molding 21 that is curved in an arch shape. Here, the groove 23 follows a simple shape curved in an arch shape, but the predetermined shape along which the groove 23 follows may be a complex three-dimensional shape in which more curves and faces are combined than a simple basic shape such as a flat plate and a shape curved in an arch shape. The transparent resin molding 21 is made of a transparent resin and transmits light. The transparent resin molding 21 may be translucent.

[0017] The colored resin filler 22 is made of a colored resin filled in the groove 23. The colored resin filler 22 made of a colored resin can block light traveling through the transparent resin molding 21. Since such a colored resin filler 22 is arranged along the predetermined shape of the transparent resin molding 21, it is possible to reduce light leaking from the end 21E of the transparent resin molding 21. Since the colored resin filler 22 is filled in the groove 23, it is firmly bonded to the transparent resin molded body 21. In other words, the colored resin filler 22 is integrated with the transparent resin molded body 21. Since the colored resin filler 22 and the transparent resin molded body 21 are integrated, even if stress is applied to the transparent resin molded body 21 due to vibration of the automobile, no displacement occurs between the colored resin filler 22 and the transparent resin molded body 21, so that the generation of abnormal noise due to the vibration of the automobile is prevented. In addition, since the stress is distributed to the colored resin filler 22 and the transparent resin molded body 21, the stress is not concentrated on the part of the transparent resin molded body 21 that is thinned by the groove 23, so that even if the groove 23 is formed, the strength and aesthetics of the automotive display panel 20 of the transparent resin molded body 21 are prevented from being deteriorated. The display areas AR11, AR12, and AR13 of the transparent resin molding 21 are areas where display is performed using light transmitted from the back surface BS to the front surface FS. The grooves 23 are disposed between the display areas AR11, AR12, and AR13 and the end portion 21E.

[0018] A thickness TH1 of the transparent resin molding 21 at the portion of the groove 23 is 0.5 mm or more and 2 mm or less, and is set to half or less of a thickness TH2 of the transparent resin molding 21 on both sides of the groove 23. In addition, the width of the groove 23 is, for example, 1 mm or more and 5 mm or less. The automotive display panel 20 shown in FIG. 2 to FIG. 4 includes a partial light-shielding film 26. The partial light-shielding film 26 is transparent in the portions corresponding to the display areas AR11, AR12, and AR13, and is colored, for example, black in the portion corresponding to the light-shielding area AR1. The light-shielding area AR1 may be colored in a color other than black as long as it can block light from the back surface BS of the transparent resin molding 21 toward the front surface FS so as not to be emitted from the automotive display panel 20. The light-shielding area AR1 is formed, for example, by printing ink on the entire surface of the light-shielding area AR1. The partial light-shielding film 26 is, for example, a decorative film. The partial light-shielding film 26 is provided on the front surface FS of the transparent resin molding 21, for example, by insert molding during the injection molding of the transparent resin molding 21.

[0019] (1-2) Automotive display device The automotive display device 1 includes an automotive display panel 20, a liquid crystal display 2, and a light source 3. The liquid crystal display 2 and the light source 3 are arranged on the side of the back surface BS of the transparent resin molding 21. The light source 3 is a backlight for the liquid crystal display 2. Arranged on the side of the back surface BS means that it does not have to be in direct contact with the back surface BS of the transparent resin molding 21. Of course, they may be arranged so as to be in direct contact with the back surface BS of the transparent resin molding 21. The light emitted from the light source 3 passes through the liquid crystal display 2 and the transparent resin molding 21, and is emitted from the display areas AR11, AR12, and AR13 to the outside of the automotive display device 1. However, of the light emitted from the light source 3, the light that passes through the transparent resin molding 21 and heads toward the end 21E of the transparent resin molding 21 is blocked by the colored resin filler 22, and is therefore reduced compared to the case where the colored resin filler 22 is not present. A self-luminous display such as an organic light-emitting display (OLED) or a plasma display may be used instead of the liquid crystal display 2 and the light source 3. When an organic light-emitting display or a plasma display is used, since they are self-luminous and therefore function as a light source, there is no need to provide a separate light source.

[0020] (2) Manufacturing method of an automobile display device The manufacturing process of the above-mentioned display device 1 for an automobile will be described with reference to the flow chart of FIG. In the injection molding process (step S1), the transparent resin molded body 21 is injection molded. The transparent resin molded body 21 molded in the injection molding process does not yet have the grooves 23 formed therein. In other words, the predetermined shape of the transparent resin molded body 21 is the shape shown in Figs. 2 to 4 excluding the grooves 23. The transparent resin molded body 21 is molded from a transparent resin and transmits light. Examples of transparent resins include polycarbonate resin (PC) and polymethylmethacrylate resin (PMMA). In the injection molding step, the partial light-shielding film 26 may be placed in a mold, and the partial light-shielding film 26 may be provided on the surface FS of the transparent resin molded body 21 by insert molding at the same time as the injection molding. Alternatively, the partial light-shielding film 26 may be attached to the surface FS of the transparent resin molded body 21 after the injection molding. In the groove forming step (step S2), the groove 23 is formed by cutting along a predetermined shape of the transparent resin molding 21 using computerized numerical control (CNC) so as to leave a predetermined range of thickness TH1. By using computerized numerical control, it is possible to form the groove 23 along the three-dimensional shape of the transparent resin molding 21. In the transparent resin molding 21 shown in FIG. 3 and FIG. 4, the groove 23 is formed along a bow-shaped curved shape. For example, the thickness TH1 of the transparent resin molding 21 in the part where the groove 23 is formed is a constant thickness of, for example, 0.5 mm. Alternatively, the groove 23 may be formed so that the thickness TH1 of the transparent resin molding 21 in the part where the groove 23 is formed varies in the range of, for example, 0.5 mm to 1 mm, assuming that the thickness TH2 of the transparent resin molding 21 around the groove 23 is 3 mm. When the transparent resin molding 21 is used for an automobile display device 1, the thickness TH2 of the transparent resin molding 21 is, for example, 2 mm to 4 mm.

[0021] It is preferable that the thickness TH1 of the transparent resin molding 21 in the portion where the groove 23 is formed is 0.5 mm or more and 2 mm or less, and is equal to or less than half the thickness TH2 of the transparent resin molding on both sides of the groove 23. If the thickness TH1 of the transparent resin molding 21 in the portion where the groove 23 is formed is thick, more light will leak from the end 21E, etc. If the thickness TH1 of the transparent resin molding 21 in the portion where the groove 23 is formed is thin, the rigidity of the automotive display panel 20 will be reduced. The above-mentioned preferable range of the thickness TH1 is set in consideration of the balance between these two. When the grooves 23 are formed by injection molding, sink marks and warping may occur in the transparent resin molding 21. However, when the grooves 23 are formed by cutting using computer numerical control, the occurrence of sink marks and warping can be prevented. The grooves 23 are formed at least between the display regions AR11, AR12, AR13 and the end 21E of the transparent resin molding 21, and between the adjacent display regions AR11, AR12, AR13. In this first embodiment, for example, the grooves 23 are formed all around the display region AR11. However, for example, if measures are taken to prevent light leaking from the upper part of the automotive display panel 20 from being radiated into the vehicle interior using other sealing members, the formation of the grooves in the upper part of the display region AR11 may be omitted. In the filler formation step (step S3), a colored resin is filled into the grooves 23 to form a colored resin filler 22. The colored resin has the function of blocking light traveling through the transparent resin molding 21 from the display regions AR11, AR12, AR13 to the end 21E and / or toward the adjacent display regions AR11, AR12, AR13. The light traveling toward the adjacent display regions refers to the light traveling from the display region AR11 toward the display regions AR12, AR13, the light traveling from the display region AR12 toward the display regions AR11, AR13, and the light traveling from the display region AR13 toward the display regions AR11, AR12.

[0022] Colored resin is resin that has been colored by mixing a colorant into it. Examples of colorants include pigments and dyes. Examples of resins that make up colored resins include thermoplastic resins, thermosetting resins, and UV-curable resins. An example of a thermoplastic resin is polypropylene resin. An example of a thermosetting resin is urethane resin. An example of a UV-curable resin is acrylic resin. As a material for colored resins, thermoplastic resins are excellent in processability because they are softened by heat, pigments can be easily mixed in uniformly, making it easy to achieve a uniform color distribution, and they are suitable for recycling because they can be softened by heat and remolded. In the assembly process (step S4), the automotive display device 1 is assembled. In the assembly process, the automotive display panel 20 is combined with the liquid crystal display 2 and the light source 3. Alternatively, instead of the liquid crystal display 2 and the light source 3, another display and light source, for example, an organic EL display or a plasma display, can be used.

[0023] <Second embodiment> (3) Construction and manufacturing of automotive display devices In the first embodiment, various information and images are displayed using the liquid crystal display 2, the organic EL display, or the plasma display. However, some of the display devices 1 for automobiles display information by switching between on and off, such as the icons on the heater control panel 30. 6, the partial light-shielding film 26 of the display areas AR14, AR15, AR16, and AR17 of the automotive display device 1 according to the second embodiment is printed with icon patterns that transmit light only. On the back surface BS side, four LEDs 3L corresponding to the display areas AR14, AR15, AR16, and AR17 are arranged as light sources 3. A power icon is arranged in the display area AR14, and when the LED 3L corresponding to the display area AR14 is turned on, the power icon lights up. The light of the power icon conveys information to the driver that the heater is on. In the automobile display panel 20 of the automobile display device 1 of the second embodiment, similarly to the first embodiment, colored resin fillers 22 (grooves 23) are arranged between the mutually adjacent display areas AR14, AR15, AR16, and AR17. Also, colored resin fillers 22 (grooves 23) are arranged between the display areas AR14 and AR17 and the end 21E of the transparent resin molding 21. For example, even if the power icon is turned on, since the colored resin fillers 22 are arranged between the display area AR14 of the power icon and the adjacent display area AR15, leakage of light for turning on the power icon into the display area AR15 is suppressed. The display device 1 for an automobile according to the second embodiment can be manufactured using the same manufacturing flow as the display device 1 for an automobile according to the first embodiment, and therefore, a description of the manufacturing method for the display device 1 for an automobile according to the second embodiment will be omitted here.

[0024] <Third embodiment> (4) Construction and manufacturing of automotive display devices In the above-mentioned first embodiment of the display device for automobiles 1, the shape of the transparent resin molded body 21 at the location where the liquid crystal display 2 and the light source 3 are arranged remains the same as the shape formed by injection molding. An example of the configuration of the display device for automobiles 1 according to the third embodiment is shown in FIG. 7. As shown in FIG. 7, in the display device for automobiles 1 according to the third embodiment, the transparent resin molded body 21 of the display area AR11 corresponding to the location where the liquid crystal display 2 and the light source 3 are arranged is made thinner than the periphery RN1 of the display area AR11 by cutting processing using computer numerical control. In other words, the following equation is established: (thickness TH3 of the transparent resin molded body 21 at the thinned portion P1 corresponding to the display area AR11)<(thickness TH4 of the periphery RN1 of the display area AR11). The thickness TH4 of the periphery RN1 of the display region AR11 is, for example, 2 mm to 4 mm when the transparent resin molding 21 is used in the automotive display device 1. The difference (TH4-TH3) between the thickness TH3 of the transparent resin molding 21 at the thin portion P1 and the thickness TH4 of the periphery RN1 of the display region AR11 is, for example, 0.5 mm to 2 mm. 7, the wall between the periphery RN1 of the display area AR11 and the thinned portion P1 is depicted as being inclined, but this wall may be formed perpendicular to the surface of the thinned portion P1 or the surface of the periphery RN1. If the wall is vertical, it is convenient for storing the OCR, which is a fluid, and makes it easier to attach the liquid crystal display 2, for example. The manufacturing flow of the display device 1 for an automobile according to the third embodiment is shown in Fig. 8. The manufacturing flow of the display device 1 for an automobile according to the third embodiment is different from the manufacturing flow of the first embodiment shown in Fig. 5 in that a thinning process (step S2') is included. In the thinning step, similarly to the groove forming step (step S2), the display area AR11 of the transparent resin molding 21 is thinned by cutting using computer numerical control (CNC) to conform to a predetermined shape of the transparent resin molding 21. Here, the case where the thinning step (step S2') is performed after the groove forming step (step S2) has been described, but the order of performing these steps may be reversed. To thin a wide area such as the display area AR11, molding is difficult due to the fluidity of the resin because the transparent resin molded body 21 is originally thin, for example 3 mm. Thinning the display area AR11 by injection molding may cause sink marks and warping in the transparent resin molded body 21. In contrast, thinning the display area AR11 by cutting using computer numerical control eliminates the molding difficulties caused by the fluidity of the resin, and makes it possible to prevent sink marks and warping.

[0025] <Fourth embodiment> (5) Construction and manufacturing of automotive display devices In the third embodiment of the display device for automobiles 1, the liquid crystal display 2 and the light source 3 are arranged on the side of the back surface BS of the thinned transparent resin molding 21. In the third embodiment, the cutting traces remain on the back surface BS of the thinned transparent resin molding 21. In the display device for automobiles 1 of the third embodiment, the cut portion is polished to remove the cutting traces. Alternatively, in the display device for automobiles 1 of the third embodiment, a coating agent is applied to the cut portion to remove the cutting traces. However, in the display device for automobiles 1 of the third embodiment, an air layer is interposed between the liquid crystal display 2 and the light source 3 and the back surface BS of the transparent resin molding 21. In the fourth embodiment of the display device 1 for automobiles, an optical clear resin 41 or an optical clear adhesive 42 is disposed between the liquid crystal display 2 and the portion P1 that is thinner than the periphery of the display area AR11 by cutting (see FIG. 9). The optical clear resin 41 or the optical clear adhesive 42 disposed in the cutting trace penetrates into the unevenness of the cutting trace, preventing diffuse reflection caused by the cutting trace. Comparing the optical clear resin 41 and the optical clear adhesive 42, the optical clear resin 41 has higher fluidity and is more effective at filling the cutting trace, so that the optical clear resin 41 is preferable for use in the cut portion of the transparent resin molded body 21. However, the optical clear adhesive 42 is an adhesive processed into a tape shape, and is therefore superior in terms of workability. In addition, since the liquid crystal display 2 and the optical clear resin 41 or the optical clear adhesive 42 are in close contact with each other, no reflection occurs at the interface between the air and the resin, and a decrease in the amount of light directed from the liquid crystal display 2 to the surface FS of the display panel for automobiles 20 is suppressed. As a result, it is possible to prevent the visibility from being reduced due to cutting marks.

[0026] In order to prevent a decrease in visibility, it is preferable that the refractive index of the optical transparent resin 41 or the optical transparent adhesive 42 is within plus or minus 0.1 of the refractive index of the transparent resin molded body 21 (refractive index of the transparent resin molded body 21-0.1≦refractive index of the optical transparent resin 41 or the optical transparent adhesive 42≦refractive index of the transparent resin molded body 21+0.1). For example, when the transparent resin molded body 21 is a polycarbonate resin (refractive index 1.58), it is preferable to use an optical transparent resin 41 or an optical transparent adhesive 42 having a refractive index of 1.48 to 1.68 for bonding the transparent resin molded body 21 and the liquid crystal display 2. For example, when the transparent resin molded body 21 is a polymethyl methacrylate resin (refractive index 1.49), it is preferable to use an optical transparent resin 41 or an optical transparent adhesive 42 having a refractive index of 1.39 to 1.59 for bonding the transparent resin molded body 21 and the liquid crystal display 2. 8 (step S4), the optically transparent resin 41 or the optically transparent adhesive 42 is used to bond the liquid crystal display 2 to the thinned portion P1 of the optically transparent resin 41. The bonding step is a step of bonding the liquid crystal display 2 to the portion P1 that has been thinned by cutting in the thinning step using the optically transparent resin 41 or the optically transparent adhesive 42. After assembly, the optically transparent resin 41 or the optically transparent adhesive 42 is in close contact with the liquid crystal display 2 and the optically transparent resin 41. In addition, when an organic EL display or a plasma display is used instead of the liquid crystal display 2, the organic EL display or the plasma display can be bonded to the transparent resin molding 21 using the optical transparent resin 41 or the optical transparent adhesive 42.

[0027] <Fifth embodiment> (6) Construction and manufacturing of automotive display devices FIG. 10 shows an example of the configuration of the display device for an automobile according to the fifth embodiment. The display device for an automobile 1 shown in FIG. 10 is different from the display device for an automobile according to the fourth embodiment shown in FIG. 9 in that a boss 50 is provided on the back surface BS of the transparent resin molding 21, and the transmittance is adjusted to make the boss 50 difficult to see from the outside of the display panel for an automobile 20. The structure provided on the back surface BS of the transparent resin molding 21 may be other than the boss 50, for example, a rib or a clip seat. At least one of a pigment and a colorant is added to the transparent resin molding 21 in order to make the structure provided on the back surface BS of the transparent resin molding 21 difficult to see. The preferred range of the total light transmittance for making the structure provided on the back surface BS of the transparent resin molding 21 difficult to see is 20% or more and 70% or less. The total light transmittance is measured in accordance with JISK7375. The fifth embodiment of the automotive display device 1 can be manufactured using a similar manufacturing flow to the fourth embodiment of the automotive display device 1, except for the resin and mold used for the transparent resin molding 21. Therefore, a description of the manufacturing method for the fifth embodiment of the automotive display device 1 will be omitted here.

[0028] (7) Variations In the above-mentioned embodiments, the description has been focused on the case where the automobile display device 1 has a function of displaying only. However, the automobile display device 1 may be provided with a touch sensor and have a function as an input device as well as a display. The touch sensor is disposed at a position where the automobile display panel 20 can be touched to input. The touch sensor is disposed, for example, on the front surface FS or back surface BS of the transparent resin molding 21. When disposed on the front surface FS of the transparent resin molding 21, the touch sensor is disposed, for example, between the transparent resin molding 21 and the partial light-shielding film 26. When disposed on the back surface BS of the transparent resin molding 21, the touch sensor is disposed, for example, between the transparent resin molding 21 and the liquid crystal display 2.

[0029] (8) Features (8-1) The manufacturing method of the display device 1 for automobiles according to the first to fifth embodiments described above includes a groove forming step of forming the groove 23 by cutting using computer numerical control along a predetermined shape so as to leave a predetermined thickness between the display regions AR11 to AR17 and the end 21E of the transparent resin molded body 21 and / or between the display regions AR11 to AR17 adjacent to each other, and a filler forming step of filling the groove 23 with a colored resin to form the colored resin filler 22 in the groove 23. As a result, since the groove 23 is not formed by injection molding, it is possible to prevent sink marks and warping when forming the groove 23. In addition, since the colored resin is filled in the groove 23 to form the colored resin filler 22 in the groove 23, the transparent resin molded body 21 around the groove 23 is integrated with the colored resin filler 22, and the transparent resin molded body 21 is reinforced by the colored resin filler 22. As a result, it is possible to suppress the deterioration of the strength and aesthetics of the display panel for automobiles 20 caused by the formation of the groove 23 and to prevent the generation of abnormal noise caused by the vibration of the automobile. Moreover, the colored resin filler 22 in the groove 23 can reduce light leaking into the end portion 21E of the transparent resin molding 21 and / or the adjacent display regions AR11 to AR17.

[0030] (8-2) By setting the thickness TH1 (see Figure 4) of the transparent resin molding 21 left when forming the groove 23 to be between 0.5 mm and 2 mm and less than half the thickness TH2 (see Figure 4) of the transparent resin molding 21 on both sides of the groove 23, it is possible to appropriately adjust the reduction in light leakage and the suppression of a decrease in strength of the automotive display panel 20. (8-3) As explained in the third and fourth embodiments, when the display area AR11 of the transparent resin molded body 21 is thinned to a predetermined shape by cutting using computer numerical control, the difficulty of molding due to the fluidity of the resin, such as injection molding, is eliminated and molding becomes easier. Furthermore, by thinning the display area AR11 by cutting using computer numerical control, the difficulty of molding due to the fluidity of the resin is eliminated and it is possible to prevent sink marks and warpage from occurring in the display area AR11.

[0031] (8-4) As described in the fourth embodiment, by bonding, for example, a liquid crystal display 2, an organic EL display or a plasma display to the portion P1 of the transparent resin molding 21 that has been thinned by cutting using an optical transparent resin 41 or an optical transparent adhesive 42, it is possible to improve the visibility of the display. (8-5) The refractive index of the optical transparent resin 41 or the optical transparent adhesive 42 is preferably set to a value equal to or greater than the refractive index of the transparent resin molded body 21 minus 0.1 and equal to or less than the refractive index of the transparent resin molded body 21 plus 0.1. By setting the refractive index of the optical transparent resin 41 or the optical transparent adhesive 42 within such a range, the visibility of the display can be improved. Although the first to fifth embodiments of the present invention have been described above, the present invention is not limited to the above-mentioned embodiments, and various modifications are possible without departing from the gist of the invention. In particular, the multiple embodiments and modifications described in this specification can be arbitrarily combined as necessary. [Explanation of symbols]

[0032] 1 Automotive display device 2 LCD display 3 light source 3L LED 20 Automotive display panel 21 Transparent resin molding 21E End 22 Colored resin filling body 23 Groove 41 Transparent resin for optics 42 Optical transparent adhesive AR11~AR17 display area

Claims

1. an injection molding step of injection molding a transparent resin molded body having a predetermined shape and transmitting light; a groove forming step of forming a groove by cutting using computer numerical control along the predetermined shape so as to leave a predetermined thickness between a display area where display is performed using light transmitted from the back surface to the front surface of the transparent resin molding and an end portion of the transparent resin molding and / or between adjacent display areas; a filler forming step of filling the grooves with a colored resin that blocks light traveling through the transparent resin molding to form a colored resin filler in the grooves; A method for manufacturing a display device for an automobile, comprising:

2. The predetermined range is 0.5 mm or more and 2 mm or less, and is equal to or less than half the thickness of the transparent resin molding on both sides of the groove. The method for manufacturing the display device for an automobile according to claim 1 .

3. a thinning process for thinning the display area of ​​the transparent resin molded body according to the predetermined shape by cutting using computer numerical control; A method for manufacturing the display device for an automobile according to claim 1 or 2.

4. a bonding process of bonding a display to the portion thinned by cutting in the thinning process using an optical clear resin or an optical clear adhesive; The method for manufacturing the display device for an automobile according to claim 3 .

5. The refractive index of the optical transparent resin or the optical transparent adhesive is equal to or greater than the refractive index of the transparent resin molded body minus 0.1 and equal to or less than the refractive index of the transparent resin molded body plus 0.

1. The method for manufacturing the display device for an automobile according to claim 4 .

6. a transparent resin molding having a predetermined shape and a groove formed by cutting along the predetermined shape, the transparent resin molding being transparent and transmitting light; A colored resin filler that is filled in the groove and is made of a colored resin that blocks light traveling through the transparent resin molded body; Equipped with the transparent resin molding has a display area for displaying information by light transmitted from a rear surface to a front surface, The groove is disposed between the display area and an end of the transparent resin molding and / or between adjacent display areas, A display panel for an automobile, wherein the thickness of the groove portion of the transparent resin molding is 0.5 mm or more and 2 mm or less, and is half or less of the thickness of the transparent resin molding on both sides of the groove.

7. The transparent resin molding has a display area that is thinner than the surrounding area of ​​the display area by cutting.

7. The display panel for an automobile according to claim 6.

8. a transparent resin molding having a predetermined shape and a groove formed by cutting along the predetermined shape, the transparent resin molding being transparent and transmitting light; A colored resin filler that is filled in the groove and is made of a colored resin that blocks light traveling through the transparent resin molded body; a light source that is disposed on the back surface side of the transparent resin molding and emits light that passes through the transparent resin molding; Equipped with the transparent resin molding has a display area for displaying information by light transmitted from the back surface to the front surface, The groove is disposed between the display area and an end of the transparent resin molding and / or between adjacent display areas, A display device for an automobile, wherein the thickness of the groove portion of the transparent resin molding is 0.5 mm or more and 2 mm or less, and is half or less of the thickness of the transparent resin molding on both sides of the groove.

9. the transparent resin molding has a display area that is made thinner than the surrounding area of ​​the display area by cutting; An optical clear resin or an optical clear adhesive is provided for bonding a display that is displayed by the light source to a thin portion of the display area. The display device for an automobile according to claim 8.

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