Method for manufacturing automotive display device, automotive display panel, and automotive display device

Abstract

The invention relates to a method for manufacturing a display device for an automobile, a display panel for an automobile, and a display device for an automobile. Provided are a display panel for an automobile and a display device for an automobile provided with such a display panel for an automobile, the display panel for an automobile not reducing the strength and appearance of the display panel for an automobile, not generating abnormal sound in the display panel for an automobile, and reducing the leakage of light, and a display device for an automobile provided with such a display panel for an automobile. In the groove forming step, a groove is formed between display regions (AR11, AR12), which are displayed by light transmitted from the back surface (BS) to the front surface (FS) of the transparent resin molded body (21), and an end portion (21E) of the transparent resin molded body (21), and / or between display regions (AR11, AR12) adjacent to each other, by cutting using computer numerical control along a predetermined shape so as to leave a thickness (TH1) of a predetermined range. Thus, the groove (23) is formed. In the filling body forming step, the groove is filled with a colored resin that shields light traveling through the transparent resin molded body (21), and a colored resin filling body (22) is formed in the groove.

Description

Technical Field

[0001] This invention relates to a method for manufacturing a display device for automobiles, a display panel for automobiles, and a display device for automobiles. Background Technology

[0002] A display device is provided on the instrument panel of the car. On the display device on the instrument panel, for example, there is a display for a navigation system as described in Patent Document 1 (Japanese Invention Patent No. 7125713) and icons for a heater control panel.

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Invention Patent No. 7125713 Summary of the Invention

[0006] The technical problem that the invention aims to solve

[0007] In automotive display devices, light propagates through the transparent resin molded body of the automotive display panel and the heater control panel; for example, sometimes light leaks out from the ends of the transparent resin molded body. Inside a car at night, when light leaks out from the ends of the automotive display panel or heater control panel, the leaked light is very noticeable.

[0008] To reduce light leakage from the ends of such transparent resin molded bodies, light-blocking units can be installed at the light-leaking areas. However, when the shape of the transparent resin molded body becomes complex to accommodate these light-blocking units, the surface of the automotive display panel may sometimes be aesthetically unappealing due to shrinkage marks or other defects after molding. In cases where the surface of the transparent resin molded body is unsightly, the automotive display panel, located in front of the driver and passengers, may be deemed a defective product.

[0009] Furthermore, given the high likelihood of drivers or passengers colliding with the dashboard in traffic accidents, it is expected that automotive display panels located on the dashboard will help protect drivers and passengers in emergencies such as accidents. Moreover, efforts are being made to suppress abnormal noises caused by reduced strength and friction between various parts in automotive display panels.

[0010] The technical problem of the present invention is to provide an automotive display panel and an automotive display device having such an automotive display panel, wherein the automotive display panel does not reduce the strength and aesthetics of the automotive display panel, does not produce abnormal noise in the automotive display panel, and reduces light leakage.

[0011] Technical solutions for solving technical problems

[0012] The following describes various methods as technical solutions for addressing technical problems. These methods can be combined arbitrarily as needed.

[0013] The first aspect of the present invention relates to a method for manufacturing an automotive display device, comprising an injection molding process, a groove forming process, and a filler forming process. The injection molding process involves injection molding a transparent resin molded body having a predetermined shape and transmitting light. The groove forming process forms a groove along a predetermined shape by computer-controlled machining, leaving a predetermined thickness between the display area (which is displayed by light transmitted from the back side of the transparent resin molded body to its surface) and the ends of the transparent resin molded body, and / or between adjacent display areas. The filler forming process fills the groove with a colored resin that blocks light traveling within the transparent resin molded body, thus forming a colored resin filler within the groove.

[0014] Since the manufacturing method for the automotive display device of the first aspect includes a groove forming process and a filler forming process without forming the groove by injection molding, shrinkage marks and warping during groove formation can be prevented. Furthermore, since a colored resin filler is formed within the groove by filling it with colored resin, the transparent resin molded body surrounding the groove is integrated with the colored resin filler, and the transparent resin molded body is reinforced by the colored resin filler. This suppresses the reduction in strength of the automotive display panel caused by groove formation and prevents rattling noises in the automotive display panel caused by vehicle vibrations. The colored resin filler in the groove also reduces light leakage to the ends of the transparent resin molded body and / or adjacent display areas.

[0015] The manufacturing method of the automotive display device according to the second aspect of the present invention is configured such that, in the manufacturing method of the automotive display device of the first aspect, the specified range is 0.5 mm or more and 2 mm or less, and is less than half the thickness of the transparent resin molded body on both sides of the groove.

[0016] According to the manufacturing method of the automotive display device in the second aspect, it is possible to appropriately adjust the reduction of light leakage and the suppression of the decrease in intensity of the automotive display panel.

[0017] The third aspect of the present invention relates to a method for manufacturing an automotive display device, which, in the method for manufacturing an automotive display device of the first or second aspect, includes a thinning process, wherein the thinning process is performed by using computer numerical control cutting to process the display area of ​​a transparent resin molded body into a thin wall along a predetermined shape.

[0018] According to the manufacturing method of the automotive display device in the third aspect, molding difficulties caused by the fluidity of resin, such as in injection molding, can be eliminated, making molding easier. Furthermore, by using computer numerical control-based cutting to thin the display area, molding difficulties caused by resin fluidity can be eliminated, preventing shrinkage marks and warping in the display area.

[0019] The fourth aspect of the present invention relates to a method for manufacturing an automotive display device, which, in the third aspect of the method for manufacturing an automotive display device, includes a bonding step in which a display is bonded to a portion that has been thinned by cutting in a thinning process using an optically transparent resin or an optically transparent adhesive.

[0020] According to the manufacturing method of the automotive display device in the fourth aspect, the visibility of the display can be improved by bonding an optically transparent resin or an optically transparent adhesive to a portion of the transparent resin molded body that has been thinned by cutting.

[0021] The fifth aspect of the present invention relates to a method for manufacturing an automotive display device, wherein, in the method for manufacturing an automotive display device of the fourth aspect, the refractive index of the optical transparent resin or the optical transparent adhesive is a value obtained by subtracting 0.1 from the refractive index of the transparent resin molded body and a value obtained by adding 0.1 to the refractive index of the transparent resin molded body.

[0022] According to the fifth aspect of the manufacturing method for an automotive display device, by setting the refractive index of the optical transparent resin or the optical transparent adhesive to a value greater than or equal to the refractive index of the transparent resin molded body 21 minus 0.1 and less than the refractive index of the transparent resin molded body 21 plus 0.1, the visibility of the display can be improved compared to the case where the refractive index is set outside this range.

[0023] The sixth aspect of the present invention relates to an automotive display panel comprising: a transparent resin molded body having a predetermined shape and a groove formed by cutting along the predetermined shape, through which light is transmitted; and a colored resin filler filled in the groove, formed of a colored resin that blocks light traveling within the transparent resin molded body. The transparent resin molded body has a display area that is displayed by light transmitted from the back side to the surface. The groove is disposed between the display area and the ends of the transparent resin molded body, and / or between adjacent display areas, wherein the thickness of the groove portion of the transparent resin molded body is 0.5 mm or more and 2 mm or less, and is less than half the thickness of the transparent resin molded body on both sides of the groove.

[0024] Because the automotive display panel in the sixth aspect forms grooves through machining, shrinkage marks and warping during groove formation can be prevented. Furthermore, since coloring resin is filled into the grooves and a coloring resin filler is formed within them, the transparent resin molded body surrounding the grooves is integrated with the coloring resin filler, and the transparent resin molded body is reinforced by the coloring resin filler. This suppresses the reduction in strength of the automotive display panel caused by groove formation and prevents rattling noises in the automotive display panel caused by vehicle vibrations. The coloring resin filler in the grooves reduces light leakage to the ends of the transparent resin molded body and / or adjacent display areas. Moreover, the reduction in light leakage and the suppression of strength reduction in the automotive display panel can be appropriately adjusted.

[0025] The seventh aspect of the present invention relates to an automotive display panel, in which, in the automotive display panel of the sixth aspect, the display area of ​​the transparent resin molded body is made thinner than the surrounding wall of the display area by cutting.

[0026] According to the seventh aspect, the automotive display panel can prevent shrinkage and warping in the display area and give the display area a good aesthetic appearance.

[0027] The automotive display device according to the 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, through which light is transmitted; a colored resin filler filled in the groove, formed of a colored resin that blocks light traveling in the transparent resin molded body; and a light source disposed on one side of the back surface of the transparent resin molded body, emitting light transmitted through the transparent resin molded body. The transparent resin molded body has a display area that is displayed by light transmitted from the back surface to the surface. The groove is disposed between the display area and the end of the transparent resin molded body, and / or between adjacent display areas. The thickness of the groove portion of the transparent resin molded body is 0.5 mm or more and 2 mm or less, and is less than half the thickness of the transparent resin molded body on both sides of the groove.

[0028] Because the automotive display device of the eighth aspect forms grooves through machining, shrinkage marks and warping during groove formation can be prevented. Furthermore, since colored resin is filled into the groove and a colored resin filler is formed within it, the transparent resin molded body surrounding the groove is integrated with the colored resin filler, and the transparent resin molded body is reinforced by the colored resin filler. This suppresses the reduction in the strength of the automotive display device caused by groove formation and prevents abnormal noises in the automotive display panel caused by vehicle vibrations. The colored resin filler in the groove reduces light leakage to the ends of the transparent resin molded body and / or adjacent display areas. Moreover, the reduction in light leakage and the suppression of the reduction in the strength of the automotive display device can be appropriately adjusted.

[0029] The ninth aspect of the present invention relates to an automotive display device, in which, in the automotive display device of the eighth aspect, the display area of ​​the transparent resin molded body is made thinner than the surrounding wall of the display area through a cutting process. It includes an optically transparent resin or an optically transparent adhesive for bonding the display, which displays via a light source, to a portion of the thin wall of the display area.

[0030] According to the ninth aspect of the automotive display device, shrinkage marks and warping in the display area can be prevented, thus giving the display area a good aesthetic appearance. Furthermore, by using an optically transparent resin or optically transparent adhesive bonded to the thin-walled portion of the transparent resin molded body through machining, the visibility of the display can be improved.

[0031] Invention Effects

[0032] According to the manufacturing method of the automotive display device of the present invention, an automotive display device can be provided 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 in the automotive display panel. The automotive display panel or automotive display device according to the present invention can prevent the reduction of strength and aesthetics, prevent the generation of abnormal noise, and reduce light leakage. Attached Figure Description

[0033] Figure 1 This is a schematic front view of the instrument panel used to illustrate the configuration of the automotive display devices in the instrument panel.

[0034] Figure 2 This is a perspective view showing an example of the structure of an automotive display panel according to the first embodiment.

[0035] Figure 3 It is along Figure 2 A cross-sectional view of an automotive display panel cut along line II.

[0036] Figure 4 It is along Figure 2 A cross-sectional view of an automotive display panel cut along line II-II.

[0037] Figure 5 This is a flowchart illustrating an example of the manufacturing process of an automotive display device according to the first embodiment.

[0038] Figure 6 This is a cross-sectional view showing an example of the structure of an automotive display panel according to the second embodiment.

[0039] Figure 7 This is a cross-sectional view showing an example of the structure of an automotive display panel according to the third embodiment.

[0040] Figure 8 This is a flowchart illustrating an example of the manufacturing process of an automotive display panel according to the third embodiment.

[0041] Figure 9 This is a cross-sectional view showing an example of the structure of an automotive display panel according to the fourth embodiment.

[0042] Figure 10 This is a cross-sectional view showing an example of the structure of a display panel for automobiles according to the fifth embodiment. Detailed Implementation

[0043] <First Implementation Method>

[0044] (1) Structure of automotive display devices

[0045] exist Figure 1 The image shows an instrument panel 10 of a car. The instrument panel 10 includes gauges such as a speedometer 11. The instrument panel 10 also includes a dashboard 12. A steering wheel 90 is positioned near the front of the instrument panel 10.

[0046] A car display panel 20 is positioned in the center of the instrument panel 10. The car display panel 20 may be a component of a navigation system. Below the car display panel 20 is a heater control panel 30. When controlling cooling, the term "air conditioning control panel" may be used instead of "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 may be a number indicating the temperature or an arrow icon. The heater symbol is represented by a wavy line design. The heater symbol indicates that the heater is operating. The mode switching icon indicates switching between heater modes (heating, cooling, fan). The power icon indicates whether the heater's power is on or off.

[0047] (1-1) Automotive display panel

[0048] exist Figure 2 An example of an automotive display panel 20 is shown. The automotive display panel 20 has... Figure 3 as well as Figure 4 The transparent resin molded body 21 and the colored resin filler 22 are shown. Figure 3 The middle shows along Figure 2 The cross-sectional shape of the section cut along line II, in Figure 4 The middle shows along Figure 2 The cross-sectional shape of the section cut along line II-II.

[0049] Viewed from the front, a trapezoidal transparent first display area AR11, formed by a transparent resin molded body 21, is disposed in the center of the automotive display panel 20. Below the first display area AR11, a generally rectangular second display area AR12 and a third display area AR13 are disposed. An opening 25, for example, for accommodating a knob, is disposed between the second display area AR12 and the third display area AR13. Viewed from the front, a light-shielding area AR2 for preventing light transmission is disposed around the display areas AR11, AR12, and AR13.

[0050] The transparent resin molded body 21 has a predetermined shape. Viewed from the front, the predetermined shape is rectangular, with a cross-section bent into an arc shape and having an opening 25. The transparent resin molded body 21 has a groove 23 formed by cutting. The groove 23 follows the predetermined shape of the transparent resin molded body 21. In other words, Figure 3 as well as Figure 4 The groove 23 shown is curved into an arc shape along the surface of the transparent resin molded body 21. Here, the groove 23 follows a simple arc shape, but the predetermined shape along which the groove 23 follows can also be a complex three-dimensional shape obtained by combining curves and surfaces that are more complex than simple basic shapes such as a flat plate and an arc shape. The transparent resin molded body 21 is formed of transparent resin and transmits light. The transparent resin molded body 21 can also be translucent.

[0051] The colored resin filler 22 is formed from colored resin filled in the groove 23. The colored resin filler 22 formed from colored resin can block light traveling in the transparent resin molded body 21. Since such colored resin filler 22 is arranged along the predetermined shape of the transparent resin molded body 21, light leakage from the end 21E of the transparent resin molded body 21 can be reduced.

[0052] Since the colored resin filler 22 is filled within the groove 23, it is firmly bonded to the transparent resin molded body 21. In other words, the colored resin filler 22 and the transparent resin molded body 21 are integrated. Because 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 by vibrations of a vehicle, for example, there will be no shift between the colored resin filler 22 and the transparent resin molded body 21, thus preventing the generation of abnormal noises associated with vehicle vibrations. Furthermore, since stress is dispersed between the colored resin filler 22 and the transparent resin molded body 21, and stress does not concentrate on the thinned portion of the transparent resin molded body 21 within the groove 23, even with the formation of the groove 23, the transparent resin molded body 21 is prevented from reducing the strength and aesthetics of the automotive display panel 20.

[0053] The transparent resin molded body 21 has display areas AR11, AR12, and AR13, which are areas displayed by light transmitted from the back side BS to the surface FS. The groove 23 is disposed between the display areas AR11, AR12, and AR13 and the end 21E.

[0054] The thickness TH1 of the groove 23 portion of the transparent resin molded body 21 is 0.5 mm or more and 2 mm or less, and is set to be less than half of the thickness TH2 of the transparent resin molded body 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.

[0055] Figures 2-4 The automotive display panel 20 shown includes a partial light-shielding film 26. The portions of the partial light-shielding film 26 corresponding to display areas AR11, AR12, and AR13 are transparent, while the portion corresponding to the light-shielding area AR1 is, for example, colored black. Since the light-shielding area AR1 only needs to block light emitted from the back surface BS of the transparent resin molded body 21 towards the surface FS, it can also be colored with a color other than black. The light-shielding area AR1 is formed, for example, by printing ink on the front 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, for example, provided on the surface FS of the transparent resin molded body 21 by insert molding during injection molding of the transparent resin molded body 21.

[0056] (1-2) Automotive display devices

[0057] The automotive display device 1 includes an automotive display panel 20, a liquid crystal display (LCD) 2, and a light source 3. The LCD 2 and the light source 3 are disposed on the back side (BS) of the transparent resin molded body 21. The light source 3 is the backlight of the LCD 2. Distributing them on the back side (BS) means that they may not be in direct contact with the back side (BS) of the transparent resin molded body 21. Of course, they may also be in direct contact with the back side (BS) of the transparent resin molded body 21.

[0058] Light emitted from the light source 3 passes through the liquid crystal display 2, through the transparent resin molded body 21, and radiates from the display areas AR11, AR12, and AR13 to the outside of the automotive display device 1. However, since the light emitted from the light source 3 that passes through the transparent resin molded body 21 and is directed toward the end 21E of the transparent resin molded body 21 is blocked by the colored resin filler 22, the amount of light emitted is reduced compared to the case without the colored resin filler 22.

[0059] Alternatively, self-emissive displays such as OLEDs or plasma displays can be used to replace the LCD 2 and the light source 3. When using OLEDs or plasma displays, since they are self-emissive and become their own light source, there is no need to set up a separate light source.

[0060] (2) Manufacturing method of automotive display device

[0061] Along Figure 5 The flowchart above describes the manufacturing process of the automotive display device 1.

[0062] In the injection molding process (step S1), the transparent resin molded body 21 is injection molded. The groove 23 has not yet been formed in the transparent resin molded body 21 formed in the injection molding process. That is, the transparent resin molded body 21 has a predetermined shape. Figures 2-4 The shapes shown are all except for groove 23. The transparent resin molded body 21 is molded from transparent resin and transmits light. Examples of transparent resins include polycarbonate resin (PC) and polymethyl methacrylate resin (PMMA).

[0063] During the injection molding process, a portion of the light-shielding film 26 can be placed inside the mold, and simultaneously with injection molding, a portion of the light-shielding film 26 can be applied to the surface FS of the transparent resin molded body 21 through insert molding. Alternatively, a portion of the light-shielding film 26 can be bonded to the surface FS of the transparent resin molded body 21 after injection molding.

[0064] In the groove forming process (step S2), the groove 23 is formed along the predetermined shape of the transparent resin molded body 21, leaving a thickness TH1 within a specified range, using computer numerical control (CNC). By using computer numerical control, the groove 23 can be formed along the three-dimensional shape of the transparent resin molded body 21. Figure 3 as well as Figure 4 In the transparent resin molded body 21 shown, a groove 23 is formed along a curved, bow-shaped form. For example, the thickness TH1 of the transparent resin molded body 21 forming the groove 23 is a constant thickness of 0.5 mm. Alternatively, for example, when the thickness TH2 of the transparent resin molded body 21 surrounding the groove 23 is set to 3 mm, the thickness TH1 of the transparent resin molded body 21 forming the groove 23 can also be formed in a manner that varies within the range of 0.5 mm to 1 mm. When the transparent resin molded body 21 is used in an automotive display device 1, the thickness TH2 of the transparent resin molded body 21 is, for example, 2 mm to 4 mm.

[0065] The thickness TH1 of the transparent resin molded body 21 forming the groove 23 is preferably 0.5 mm or more and 2 mm or less, and is less than half the thickness TH2 of the transparent resin molded bodies on both sides of the groove 23. When the thickness TH1 of the transparent resin molded body 21 forming the groove 23 becomes thicker, more light leaks out from the end 21E, etc. When the thickness TH1 of the transparent resin molded body 21 forming the groove 23 becomes thinner, the rigidity of the automotive display panel 20 decreases. The preferred range of the thickness TH1 is set by considering the balance between the two.

[0066] When the groove 23 is formed by injection molding, shrinkage marks and warping may sometimes occur in the transparent resin molded body 21. However, when the groove 23 is formed by machining based on computer numerical control, shrinkage marks and warping can be prevented.

[0067] At least between the display areas AR11, AR12, AR13 and the end 21E of the transparent resin molded body 21, and between adjacent display areas AR11, AR12, AR13, a groove 23 is formed. In this first embodiment, for example, the groove 23 is formed around the entire periphery of the display area AR11. However, for example, if light leaking from the upper part of the automotive display panel 20 is prevented from radiating into the vehicle interior by other sealing members, the formation of the groove in the upper part of the display area AR11 may be omitted.

[0068] In the filler formation process (step S3), colored resin is filled into the groove 23 to form a colored resin filler 22. The colored resin has the function of shielding light traveling from the display areas AR11, AR12, AR13 toward the end 21E and / or adjacent display areas AR11, AR12, AR13 in the transparent resin molded body 21. Light toward adjacent display areas refers to light from display area AR11 toward display areas AR12, AR13, light from display area AR12 toward display areas AR11, AR13, and light from display area AR13 toward display areas AR11, AR12.

[0069] Coloring resins are resins that are colored by incorporating colorants. Examples of colorants include pigments and dyes. Examples of resins that constitute coloring resins include thermoplastic resins, thermosetting resins, and UV-curing resins. Examples of thermoplastic resins include polypropylene resins. Examples of thermosetting resins include polyurethane resins. Examples of UV-curing resins include acrylic resins. As materials for coloring resins, thermoplastic resins have excellent processability because they soften with heat; they are easy to uniformly mix with pigments, making it easy to achieve a uniform color distribution; and they are suitable for reuse because they can be reshaped by softening with heat.

[0070] In the assembly process (step S4), the automotive display device 1 is assembled. In this assembly process, the liquid crystal display 2 and the light source 3 are combined with the automotive display panel 20. Alternatively, other displays and light sources, such as organic EL displays or plasma displays, can be used instead of the liquid crystal display 2 and the light source 3.

[0071] <Second Implementation Method>

[0072] (3) Structure and manufacturing of automotive display devices

[0073] In the first embodiment, a liquid crystal display 2, an organic EL display, or a plasma display were used to describe the display of various information and images. However, in the automotive display device 1, there are also displays that are switched on and off, similar to the icons on the heater control panel 30.

[0074] exist Figure 6 In this embodiment, the light-shielding film 26 of the display areas AR14, AR15, AR16, and AR17 of the automotive display device 1 is printed with a graphic showing that only icons are transmitted through light. Four LED 3L light sources 3 corresponding to the display areas AR14, AR15, AR16, and AR17 are arranged on the back side BS. A power icon is arranged in the display area AR14; when the LED 3L corresponding to the display area AR14 is lit, the power icon illuminates. The illuminated power icon conveys the information that the heater is on to the driver.

[0075] In the automotive display panel 20 of the automotive display device 1 according to the second embodiment, similarly to the first embodiment, a colored resin filler 22 (groove 23) is also disposed between adjacent display areas AR14, AR15, AR16, and AR17. Furthermore, the colored resin filler 22 (groove 23) may also be disposed between display areas AR14 and AR17 and the end 21E of the transparent resin molded body 21. For example, even when the power icon is lit, since the colored resin filler 22 is also disposed between the power icon and the adjacent display area AR15, leakage of light used to light the power icon into the display area AR15 can be suppressed.

[0076] Since the automotive display device 1 of the second embodiment can be manufactured using the same manufacturing process as the automotive display device 1 of the first embodiment, the description of the manufacturing method of the automotive display device 1 of the second embodiment is omitted here.

[0077] <Third Implementation Method>

[0078] (4) Structure and manufacturing of automotive display devices

[0079] In the automotive display device 1 of the first embodiment described above, the transparent resin molded body 21 at the location where the liquid crystal display 2 and the light source 3 are disposed retains the shape formed by injection molding. Figure 7 An example of the structure of the automotive display device 1 according to the third embodiment is shown. For example... Figure 7 As shown, in the automotive display device 1 according to the third embodiment, the transparent resin molded body 21 of the display area AR11 corresponding to the part where the liquid crystal display 2 and the light source 3 are disposed is made thinner than the surrounding RN1 of the display area AR11 by using computer numerical control cutting. That is, the formula (the thickness TH3 of the transparent resin molded body 21 that becomes the thinner part P1 corresponding to the display area AR11) < (the thickness TH4 of the surrounding RN1 of the display area AR11) holds true.

[0080] When the transparent resin molded body 21 is used in the automotive display device 1, the thickness TH4 of the circumference RN1 of the display area AR11 is, for example, 2 mm to 4 mm. In addition, the difference between the thickness TH3 of the transparent resin molded body 21 of the thin-walled portion P1 and the thickness TH4 of the circumference RN1 of the display area AR11 (TH4-TH3) is, for example, 0.5 mm to 2 mm.

[0081] In addition, Figure 7 In the diagram, the wall between the surrounding RN1 of the display area AR11 and the thin-walled portion P1 is depicted as inclined, but this wall can also be formed perpendicularly to the surface of the thin-walled portion P1 or the surface of the surrounding RN1. If the wall is perpendicular, it facilitates the storage of fluids, i.e., OCR, for example, making it easier to attach to the liquid crystal display 2.

[0082] exist Figure 8 The manufacturing process of the automotive display device 1 according to the third embodiment is shown. The manufacturing process of the automotive display device 1 according to the third embodiment is similar to... Figure 5 The difference in the manufacturing process of the first embodiment shown is that it includes a thin-wall process (step S2').

[0083] In the thinning process, similar to the groove forming process (step S2), the display area AR11 of the transparent resin molded body 21 is thinned by cutting using computer numerical control (CNC) along the predetermined shape of the transparent resin molded body 21. Here, the case where the thinning process (step S2') is performed after the groove forming process (step S2) is described, but the order of these processes can also be replaced.

[0084] To achieve a thinner wall for a wide area like the display area AR11, the original transparent resin molded body 21, which is relatively thin (e.g., 3 mm), is difficult to mold due to the resin's fluidity. When the display area AR11 is thinned by injection molding, shrinkage marks and warping sometimes occur in the transparent resin molded body 21. In contrast, when the display area AR11 is thinned by machining based on computer numerical control, the molding difficulties caused by the resin's fluidity can be eliminated, and shrinkage marks and warping can be prevented.

[0085] <Fourth Implementation Method>

[0086] (5) Structure and manufacturing of automotive display devices

[0087] In the automotive display device 1 of the third embodiment, the case where the liquid crystal display 2 and the light source 3 are disposed on the back side BS of the thin-walled transparent resin molded body 21 is described. In the third embodiment, the back side BS of the thin-walled transparent resin molded body 21 has residual cutting marks from the cutting process. In the automotive display device 1 of the third embodiment, the cut portion is polished to eliminate the cutting marks. Alternatively, in the automotive display device 1 of the third embodiment, the cut portion is coated with a coating agent to eliminate the cutting marks. However, in the automotive display device 1 of the third embodiment, an air layer is disposed between the liquid crystal display 2 and the light source 3 and the back side BS of the transparent resin molded body 21.

[0088] In the automotive display device 1 of the fourth embodiment, an optically clear resin 41 or an optically clear adhesive 42 is disposed between the portion P1, which is made thinner than the surrounding wall of the display area AR11 by machining, and the liquid crystal display 2 (see reference). Figure 9 The optically transparent resin 41 or optically transparent adhesive 42, disposed on the cutting marks, penetrates into the unevenness of the cutting marks to prevent diffuse reflection generated in the cutting marks. When comparing the optically transparent resin 41 and the optically transparent adhesive 42, the optically transparent resin 41 has higher fluidity and a better effect in filling the cutting marks. Therefore, it is preferable to use the optically transparent resin 41 on the cutting parts of the transparent resin molded body 21. However, since the optically transparent adhesive 42 is processed into a strip, it is superior in terms of workability. In addition, since the liquid crystal display 2 is in close contact with the optically transparent resin 41 or optically transparent adhesive 42, reflection at the air-resin interface is not generated, and the reduction in the amount of light from the liquid crystal display 2 toward the surface FS of the automotive display panel 20 can be suppressed. As a result, the reduction in visibility due to cutting marks can be prevented.

[0089] To prevent a decrease in visibility, the refractive index of the optically transparent resin 41 or the optically transparent adhesive 42 is preferably within ±0.1 of the refractive index of the transparent resin molded body 21 (refractive index of transparent resin molded body 21 -0.1 ≤ refractive index of optically transparent resin 41 or optically transparent adhesive 42 ≤ refractive index of transparent resin molded body 21 +0.1). For example, when the transparent resin molded body 21 is polycarbonate resin (refractive index 1.58), it is preferable to use optically transparent resin 41 or optically transparent adhesive 42 with a refractive index of 1.48 to 1.68 for bonding the transparent resin molded body 21 to the liquid crystal display 2. For example, when the transparent resin molded body 21 is polymethyl methacrylate resin (refractive index 1.49), it is preferable to use optically transparent resin 41 or optically transparent adhesive 42 with a refractive index of 1.39 to 1.59 for bonding the transparent resin molded body 21 to the liquid crystal display 2.

[0090] exist Figure 8 In the assembly process (step S4), optically transparent resin 41 or optically transparent adhesive 42 is used to bond the liquid crystal display 2 to the thin-walled portion P1 that has been transformed into optically transparent resin 41. The process of bonding the liquid crystal display 2 to the thin-walled portion P1, which has been thinned through cutting in the thinning process, using optically transparent resin 41 or optically transparent adhesive 42 is a bonding process. After assembly, the optically transparent resin 41 or optically transparent adhesive 42 is firmly bonded to the liquid crystal display 2 and the optically transparent resin 41.

[0091] In addition, when using an organic EL display or a plasma display instead of a liquid crystal display 2, the organic EL display or plasma display can be bonded to the transparent resin molded body 21 using an optically transparent resin 41 or an optically transparent adhesive 42.

[0092] <Fifth Implementation Method>

[0093] (6) Structure and manufacturing of automotive display devices

[0094] exist Figure 10 An example of the structure of the automotive display device according to the fifth embodiment is shown. Figure 10 The automotive display device 1 shown is... Figure 9The difference in the fourth embodiment of the automotive display device 1 is that a boss 50 is provided on the back surface BS of the transparent resin molded body 21, and the transmittance is adjusted to make the boss 50 less visible from outside the automotive display panel 20. The structure provided on the back surface BS of the transparent resin molded body 21 can also be something other than the boss 50, such as having ribs or snap-fit ​​seats. To make the structure provided on the back surface BS of the transparent resin molded body 21 less visible, at least one of a pigment and a colorant is added to the transparent resin molded body 21. The preferred range for the total light transmittance to make the structure provided on the back surface BS of the transparent resin molded body 21 less visible is 20% or more and 70% or less. The total light transmittance is measured according to JIS K 7375.

[0095] Since the only difference between the automotive display device 1 of the fifth embodiment and the transparent resin mold 21 is the resin and the mold, it can be manufactured using the same manufacturing process as the automotive display device 1 of the fourth embodiment. Therefore, the description of the manufacturing method of the automotive display device 1 of the fifth embodiment is omitted here.

[0096] (7) Variations

[0097] In the above embodiments, the description focused on the case where the automotive display device 1 has a dedicated display function. However, the automotive display device 1 may also include a touch sensor, serving as both a display and an input device. The touch sensor is positioned at a location where input can be performed upon contact with the automotive display panel 20. The touch sensor is, for example, disposed on the surface FS or the back BS of the transparent resin molded body 21. When disposed on the surface FS of the transparent resin molded body 21, the touch sensor is disposed, for example, between the transparent resin molded body 21 and a portion of the light-shielding film 26. When disposed on the back BS of the transparent resin molded body 21, the touch sensor is disposed, for example, between the transparent resin molded body 21 and the liquid crystal display 2.

[0098] (8) Characteristics

[0099] (8-1) The manufacturing method of the automotive display device 1 according to the first to fifth embodiments described above includes: a groove forming step, in which a groove 23 is formed along a predetermined shape by computer numerical control machining, leaving a predetermined thickness between the display areas AR11 to AR17 and the end 21E of the transparent resin molded body 21, and / or between adjacent display areas AR11 to AR17; and a filler forming step, in which a colored resin is filled into the groove 23, and a colored resin filler 22 is formed in the groove 23. As a result, since the groove 23 is not formed by injection molding, shrinkage marks and warping during the formation of the groove 23 can be prevented. Furthermore, since the colored resin is filled into the groove 23 and the colored resin filler 22 is formed 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, the reduction in strength and aesthetics of the automotive display panel 20 caused by the formation of the groove 23 can be suppressed, and abnormal noises caused by vehicle vibration can be prevented. Furthermore, the colored resin filler 22 of the groove 23 can reduce the light leakage to the end 21E of the transparent resin molded body 21 and / or the adjacent display areas AR11 to AR17.

[0100] (8-2)

[0101] The thickness TH1 of the transparent resin molded body 21 left when forming the groove 23 (refer to) Figure 4 The thickness TH2 of the transparent resin molded body 22 on both sides of the groove 23 is set to be 0.5mm or more and 2mm or less (refer to...). Figure 4 This allows for appropriate adjustments to reduce light leakage and suppress the decrease in intensity of the automotive display panel 20, as the light leakage is less than half of that of the other two.

[0102] (8-3) As described in the third and fourth embodiments, when the display area AR11 of the transparent resin molded body 21 is processed into a thin wall along a predetermined shape using computer numerical control machining, molding difficulties caused by the fluidity of the resin, such as in injection molding, can be eliminated, making molding easier. Furthermore, by using computer numerical control machining to thin the display area AR11, molding difficulties caused by the fluidity of the resin can be eliminated, and shrinkage marks and warping in the display area AR11 can be prevented.

[0103] (8-4)

[0104] As described in the fourth embodiment, the visibility of the display can be improved by bonding the liquid crystal display 2, organic EL display or plasma display to the thin-walled portion P1 of the transparent resin molded body 21 through cutting by means of optical transparent resin 41 or optical transparent adhesive 42.

[0105] (8-5) The refractive index of the optical transparent resin 41 or the optical transparent adhesive 42 described above is preferably set to a value greater than or equal to the refractive index of the transparent resin molded body 21 minus 0.1, and less than or equal to 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.

[0106] The first to fifth embodiments of the present invention have been described above, but the present invention is not limited to the above embodiments, and various modifications can be made without departing from the spirit of the invention. In particular, the various embodiments and variations described in this specification can be arbitrarily combined as needed.

[0107] Explanation of reference numerals in the attached figures

[0108] 1: Automotive display device; 2: Liquid crystal display; 3: Light source; 20: Automotive display panel; 21: Transparent resin molded body; 21E: End; 22: Colored resin filler; 23: Groove; 41: Optical transparent resin; 42: Optical transparent adhesive; AR11~AR17: Display area.

Claims

1. A method for manufacturing an automotive display device, comprising: The injection molding process involves injecting a transparent resin molded body with a specified shape that transmits light. The groove forming process involves forming a groove along a predetermined shape using computer-controlled machining, between the display area (displayed by light transmitted from the back of the transparent resin molded body to the surface) and the ends of the transparent resin molded body, and / or between adjacent display areas, leaving a predetermined thickness; and In the filler forming process, a colored resin that shields light traveling in the transparent resin molded body is filled into the groove to form a colored resin filler in the groove.

2. The method for manufacturing an automotive display device according to claim 1, wherein, The specified range is 0.5 mm or more and 2 mm or less, and is less than half the thickness of the transparent resin molded body on both sides of the groove.

3. The method for manufacturing an automotive display device according to claim 1 or 2, wherein, The manufacturing method of the automotive display device includes a thin-wall process, in which the display area of ​​the transparent resin molded body is processed into a thin wall by using computer numerical control cutting along the predetermined shape.

4. The method for manufacturing an automotive display device according to claim 3, wherein, The manufacturing method of the automotive display device includes a bonding process, in which the display is bonded to the portion that has been thinned by cutting in the thinning process using optical clear resin or optical clear adhesive.

5. The method for manufacturing an automotive display device according to claim 4, wherein, The refractive index of the optical transparent resin or the optical transparent adhesive is greater than or equal to the value obtained by subtracting 0.1 from the refractive index of the transparent resin molded body, and less than or equal to the value obtained by adding 0.1 to the refractive index of the transparent resin molded body.

6. A display panel for automobiles, comprising: A transparent resin molded body having a defined shape and grooves, and the transparent resin molded body allowing light to pass through, the grooves being formed by cutting along the defined shape; and A colored resin filler is filled in the groove and is formed of a colored resin that blocks light traveling in the transparent resin molded body. The transparent resin molded body has a display area, which is displayed by light transmitted from the back side to the surface. The groove is disposed between the display area and the end of the transparent resin molded body, and / or between adjacent display areas. The thickness of the groove portion of the transparent resin molded body is 0.5 mm or more and 2 mm or less, and is less than half the thickness of the transparent resin molded body on both sides of the groove.

7. The automotive display panel according to claim 6, wherein, The display area of ​​the transparent resin molded body is made thinner than the surrounding wall of the display area by cutting.

8. A display device for automobiles, comprising: A transparent resin molded body having a defined shape and grooves, and the transparent resin molded body allows light to pass through, the grooves being formed by cutting along the defined shape; A colored resin filler is filled in the groove and is formed of a colored resin that shields light traveling in the transparent resin molded body; as well as A light source is disposed on one side of the back of the transparent resin molded body, emitting light that is transmitted through the transparent resin molded body. The transparent resin molded body has a display area, which is displayed by light transmitted from the back side to the surface. The groove is disposed between the display area and the end of the transparent resin molded body, and / or between adjacent display areas. The thickness of the groove portion of the transparent resin molded body is 0.5 mm or more and 2 mm or less, and is less than half the thickness of the transparent resin molded body on both sides of the groove.

9. The automotive display device according to claim 8, wherein, The display area of ​​the transparent resin molded body is made thinner than the surrounding wall by cutting. The automotive display device includes an optical clear resin or an optical clear adhesive, which adheres the display that is displayed by the light source to a portion of the thin wall of the display area.

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