JP2018205627A - Display panel film, method for manufacturing the same and lighting device - Google Patents

Abstract

To provide a display panel film excellent in quality and capable of suppressing bright spots; a method for manufacturing the same; and a lighting device.SOLUTION: A display panel film 8 entering and emitting light emitted from a light source 51 comprises a pattern layer 81, a diffusion layer 83, a base material 85 used as a light transmissive film and an ultraviolet absorption layer 87. In the display panel film 8, the pattern layer 81, the diffusion layer 83, the base material 85 and the ultraviolet absorption layer 87 are laminated in this order in a direction away from the side of the light source 51. The diffusion layer 83 includes a resin and light diffusion particles having a refractive index different from that of the resin, and the surface roughness is 0.5 μm or more and 3.0 μm or less. The ultraviolet absorption layer 87 has a transmittance of 50% or less at an optical wavelength of 380 nm and a transmittance of 60% or more at an optical wavelength of 400 nm.SELECTED DRAWING: Figure 2

Description

  The present disclosure relates to a display panel film, a method for manufacturing a display panel film, and an illumination device.

  Conventionally, a transflective display body in which a light diffusion film and a specular louver film having a transparent region are laminated has been disclosed (see, for example, Patent Document 1).

Japanese Patent Laying-Open No. 2015-69049

  In recent years, there has been a demand for a film for a display panel that is superior in quality to a transflective display and has reduced brightness spots.

  Then, this indication aims at providing the manufacturing method of a film for display panels, the film for display panels, and an illuminating device which are excellent in quality and can suppress a brightness spot.

  In order to achieve the above object, a film for a display panel according to one embodiment of the present invention is a film for a display panel in which light emitted from a light source is incident and emitted, and includes a pattern layer, a diffusion layer, and a translucent film. The pattern layer, the diffusion layer, the base material, and the ultraviolet absorption layer are laminated in this order in a direction away from the light source side, and the diffusion layer is a resin. And light diffusing particles having a refractive index different from that of the resin, having a surface roughness of 0.5 μm or more and 3.0 μm or less, and the ultraviolet absorbing layer has a transmittance of 50% for a light wavelength of 380 nm. Hereinafter, the transmittance for light having a wavelength of 400 nm is 60% or more.

  Moreover, in order to achieve the said objective, the manufacturing method of the film for display panels which concerns on 1 aspect of this invention is the film for display panels which manufactures the film for display panels by selectively performing gravure printing and screen printing at least. The method of manufacturing, wherein an ultraviolet absorbing layer is applied to the first surface of the substrate, the coated ultraviolet absorbing layer is dried, and the second surface of the substrate is opposite to the first surface. The diffusion layer is applied, the applied diffusion layer is dried, the pattern layer is further applied to the diffusion layer, and the applied pattern layer is dried.

  In order to achieve the above object, an illumination device according to one embodiment of the present invention includes a light source, a display panel film, and a light guide that guides light emitted from the light source and irradiates the display panel film. A light plate.

  According to the present disclosure, it is excellent in quality and luminance spots can be suppressed.

FIG. 1 is a perspective view showing a lighting device according to an embodiment. FIG. 2 is an exploded perspective view showing a light guide plate, a light emitting module, and a display panel film in the lighting apparatus according to the embodiment. FIG. 3 is a partially enlarged cross-sectional view showing a display panel film according to the embodiment taken along line III-III in FIG. 2. FIG. 4 is a flowchart showing the display panel film according to the embodiment. FIG. 5 is an explanatory view showing the process from the preparation process of FIG. 4 to the drying process of the ultraviolet absorbing layer. FIG. 6 is an explanatory view showing the process from the coating process for forming the diffusion layer shown in FIG. 4 to the completion of the display panel film. FIG. 7 is a diagram showing the evaluation results of the display panel film.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Each of the embodiments described below shows a preferred specific example of the present invention. Therefore, the numerical values, shapes, materials, components, arrangement positions and connection forms of the components shown in the following embodiments are merely examples, and are not intended to limit the present invention. Therefore, among the constituent elements in the following embodiments, constituent elements that are not described in the independent claims showing the highest concept of the present invention are described as optional constituent elements.

  Each figure is a schematic diagram and is not necessarily illustrated strictly. Moreover, in each figure, the same code | symbol is attached | subjected to the substantially same structure, The overlapping description is abbreviate | omitted or simplified.

(Embodiment)
[Constitution]
FIG. 1 is a perspective view showing a lighting device 1 according to an embodiment. FIG. 2 is an exploded perspective view showing the light guide plate 7, the light emitting module 5, and the display panel film 8 in the lighting device according to the embodiment. FIG. 3 is a partially enlarged cross-sectional view showing the display panel film 8 according to the embodiment taken along the line III-III in FIG. 2.

  In FIG. 1, in the lighting device 1, the longitudinal direction of the light emitting module 5 is defined as the X-axis direction, the alignment direction of the light guide plate 7 and the display panel film 8 is defined as the Y-axis direction, and the X-axis direction and the Y-axis direction. The direction that intersects with is defined as the Z-axis direction. A person whose power supply unit 91 side in the housing 3 is defined as an X-axis plus direction, and a side on which the display panel film 8 is disposed with respect to the light guide plate 7 is defined as a Y-axis plus direction. Is defined as the positive direction of the Z-axis. Then, each direction shown in each figure after FIG. 2 is displayed in correspondence with each direction shown in FIG.

  As shown in FIGS. 1 to 3, the lighting device 1 is a guide light device for guidance using an edge light type light guide plate 7 and is disposed on a construction material such as a ceiling or a wall. The illuminating device 1 is attached to construction materials, such as a house, an office, a warehouse, for example.

  The lighting device 1 includes a housing 3, a light emitting module 5, a display panel 6, and a power supply unit 91.

  The housing 3 is a box flat in the Y-axis direction, and is made of, for example, a metal such as aluminum or iron. The housing 3 is formed with an opening 3a that opens on the Y axis plus direction side. The housing 3 is fixed to the building material by a fixing member such as a bolt, for example. The housing 3 houses the light emitting module 5, the display panel 6, and the power supply unit 91.

  The light emitting module 5 is disposed on the inner wall surface on the Z axis plus direction side in the housing 3, and emits light to be emitted from the lighting device 1. The light emitting module 5 is a module having an LED (Light Emitting Diode). In addition, in this Embodiment, although the light emitting module 5 is arrange | positioned on the inner wall face of the Z-axis plus direction side in the housing | casing 3, the arrangement place is not specifically limited.

  The light emitting module 5 includes a light source 51 and a substrate on which the light source 51 is mounted.

  A light source 51 is mounted on the substrate. The board | substrate may be thermally connected to the housing | casing 3, for example so that the heat | fever which the light source 51 emitted may be thermally radiated. That is, the housing 3 may also serve as a heat sink. The substrate is electrically connected to the power supply unit 91 and supplied with power from the power supply unit 91.

  The light source 51 irradiates the incident surface 71 of the light guide plate 7 of the display panel 6 with light. That is, the light source 51 is disposed in the housing 3 such that the light emission direction is in the negative Z-axis direction. Specifically, the light source 51 is disposed in the housing 3 in a state of facing the incident surface 71 so that the optical axis is substantially orthogonal to the incident surface 71 of the light guide plate 7. In the present embodiment, a plurality of light sources 51 are arranged in the X-axis direction.

  A gap is provided between the light source 51 and the light guide plate 7 so that the light source 51 and the light guide plate 7 do not come into contact with each other. This is to prevent heat generated in the light source 51 from being conducted to the light guide plate 7 and damaging the light guide plate 7.

  The light source 51 is a so-called SMD (Surface Mount Device) type LED (Light Emitting Diode) element. Specifically, the SMD type LED element is a package type LED element in which an LED chip (light emitting element) is mounted in a resin-molded cavity, and a phosphor-containing resin is sealed in the cavity. The light source 51 is turned on and off by being controlled by a control circuit (not shown) provided in the power supply unit 91. The light source 51 is controlled by a control circuit provided in the power supply unit 91 to perform light adjustment and toning. For example, a surface-mounted LED element that emits white light by a combination of a blue LED chip and a yellow phosphor-containing resin is employed as the light source 51.

  The light source 51 is not limited to such a configuration, and may be used in a COB (Chip On Board) type light emitting module 5 in which an LED chip is directly mounted on a substrate. Further, the light emitting element included in the light source 51 is not limited to the LED. For example, the semiconductor light emitting element such as a semiconductor laser, or other solid light emitting elements such as an organic EL (Electro Luminescence) or an EL element such as an inorganic EL. It may be.

  The display panel 6 includes a light guide plate 7 and a display panel film 8.

  The light guide plate 7 guides the light emitted from the light source 51 and irradiates the display panel film 8. The light guide plate 7 is an optical member that has a rectangular flat plate shape in plan view and guides light from the light source 51. The light guide plate 7 is a translucent member such as a resin such as acrylic or polycarbonate, or glass, but may be formed of any other material as long as it has translucency. Note that the shape of the light guide plate 7 is not limited to a rectangular shape, and may be a disk shape or other shapes such as a polygonal shape.

  The light guide plate 7 is disposed on the Y axis plus direction side in the housing 3 so as to cover the opening 3 a of the housing 3. The light guide plate 7 is supported by a support member (not shown) of the housing 3 so as to be substantially parallel to a plane defined in the Y-axis direction and the Z-axis direction.

  The light guide plate 7 has an entrance surface 71, an exit surface 73, and a back surface 75.

  The incident surface 71 is a surface on which light from the light source 51 is incident, and is a substantially uniform plane. The incident surface 71 is a surface substantially perpendicular to the optical axis of the light source 51 so that the light emitted from the light source 51 is incident. The entrance surface 71 is a surface that intersects the exit surface 73 and the back surface 75. In the present embodiment, the incident surface 71 is a part of the side surface of the light guide plate 7 and is a surface on the Z axis plus direction side of the light guide plate 7. Note that the position of the incident surface 71 is not limited to the surface on the positive side of the Z axis, and varies depending on the position where the light emitting module 5 is disposed.

  The emission surface 73 is a surface from which the guided light is emitted. The exit surface 73 is a surface of the light guide plate 7 on the Y axis plus direction side substantially orthogonal to the entrance surface 71 and forms a substantially uniform plane.

  The back surface 75 is a surface on the opposite side facing the emission surface 73. The back surface 75 is a surface of the light guide plate 7 on the Y axis minus direction side substantially orthogonal to the incident surface 71 and forms a substantially uniform plane. A concave or convex prism is formed on the back surface 75. The shape of the prism is, for example, conical or hemispherical. When a convex prism is formed, a reflection sheet for specularly reflecting light may be provided on the back surface 75 of the light guide plate 7.

  The display panel film 8 is a translucent film through which light emitted from the light guide plate 7 enters and exits. The display panel film 8 has, for example, a rectangular shape in plan view. When the display panel 6 is viewed from the Y axis plus direction side, the display panel film 8 is disposed on the light exit surface 73 side of the light guide plate 7 so as to overlap the light guide plate 7. The display panel film 8 is disposed on the Y axis plus direction side of the light guide plate 7 so as to be substantially parallel to a plane defined by the Y axis direction and the Z axis direction. The display panel film 8 may be attached to the emission surface 73.

  The display panel film 8 includes a pattern layer 81, a diffusion layer 83, a base material 85, and an ultraviolet absorption layer 87. In the display panel film 8, a pattern layer 81, a diffusion layer 83, a base material 85, and an ultraviolet absorption layer 87 are laminated in this order in a direction away from the light source 51 side, specifically, the light guide plate 7 side.

  The picture layer 81 constitutes the picture of the display panel film 8. The pattern layer 81 is a green portion that mainly transmits green component light and has a transmittance of a predetermined ratio. For example, the pattern layer 81 diffuses light that is emitted from the emission surface 73 of the light guide plate 7 and incident on the pattern layer 81. The surface roughness of the pattern layer 81 is 1.0 μm or more and 5.0 μm or less. The pattern layer 81 is disposed so as to face the light exit surface 73 of the light guide plate 7 in the display panel 6.

  The diffusion layer 83 is laminated on the Y axis plus direction side of the pattern layer 81, in other words, on the opposite side of the pattern layer 81 from the light guide plate 7 side. The diffusion layer 83 has a light diffusion function for diffusing light. The diffusion layer 83 has a surface roughness of 0.5 μm or more and 3.0 μm or less. The diffusion layer 83 includes a resin and light diffusing particles having a refractive index different from that of the resin. The resin has translucency such as translucent acrylic or polyethylene terephthalate. Light diffusion particles are dispersed in the diffusion layer 83. The light diffusion material is, for example, benzoguanamine-based spherical resin particles.

  The base material 85 is a film having translucency that is the base of the display panel film 8. The base material 85 has a first surface 85a and a second surface 85b. The first surface 85a is a surface of the base material 85 on the Y axis plus direction side. An ultraviolet absorption layer 87 is laminated on the first surface 85a. The second surface 85b is a surface of the base material 85 on the Y axis minus direction side. A diffusion layer 83 is stacked on the second surface 85b.

  The base material 85 is made of, for example, a resin material such as acrylic or polyethylene terephthalate, or a material such as glass. The base material 85 is laminated on the Y axis plus direction side of the diffusion layer 83, in other words, on the surface of the diffusion layer 83 opposite to the surface on the light guide plate 7 side.

  The ultraviolet absorbing layer 87 is laminated on the first surface 85 a of the base material 85. The ultraviolet absorbing layer 87 has a function of absorbing ultraviolet rays. The ultraviolet absorbing layer 87 has a light transmittance of 50% or less for a light wavelength of 380 nm and a light transmittance of 60% or more for a light wavelength of 400 nm. More preferably, the ultraviolet absorption layer 87 has a light transmittance of 30% or less for a light wavelength of 380 nm and a light transmittance of 70% or more for a light wavelength of 400 nm.

The surface roughness of the ultraviolet absorbing layer 87 is not less than 0.5 μm and not more than 3.0 μm. The ultraviolet absorption layer 87 contains at least one of a surfactant, an ion conductive polymer, and a conductive metal oxide. According to this, the surface resistance value of the surface on the Y-axis direction side of the display panel film 8 is lowered. If the surface resistance value is, for example, 10 ⁻¹³ or less, dust or the like hardly adheres.

  The power supply unit 91 includes a control circuit that is driven by power from the outside, a lead wire that supplies power for causing the light source 51 to emit light, and the like. The power supply unit 91 supplies power to the light source 51 through a lead wire.

  In such an illuminating device 1, the light emitted from the light source 51 enters the incident surface 71 of the light guide plate 7, guides the light guide plate 7, is reflected by the back surface 75, and is emitted from the output surface 73. Exit. The light emitted from the emission surface 73 is incident on the display panel film 8. The light incident on the picture layer 81 of the display panel film 8 is diffused, and green light is emitted when passing through the picture layer 81. Naturally, light passes through the part of the picture layer 81 where no picture is drawn. The light transmitted through the pattern layer 81 is diffused by the light diffusing particles of the diffusion layer 83 and the surface roughness of the diffusion layer 83 and then emitted when passing through the diffusion layer 83. The light that has passed through the diffusion layer 83 passes through the ultraviolet absorption layer 87 and is emitted to the outside of the illumination device 1. When the light passes through the pattern layer 81, green light is emitted from a part of the display panel film 8 and white light is emitted from the other part of the display panel film 8. From, light corresponding to the pattern is emitted.

[Production method]
Next, the process of the manufacturing method of the display panel film 8 in this Embodiment is demonstrated using FIGS.

  FIG. 4 is a flowchart showing the display panel film 8 according to the embodiment. FIG. 5 is an explanatory view showing the process from the preparation process of FIG. 4 to the drying process of the ultraviolet absorbing layer 87. FIG. 6 is an explanatory view from the diffusion layer forming paint coating process of FIG. 4 to the completion of the display panel film 8.

  As shown in FIGS. 4-6, first, the base material 85 used as the base which manufactures the film 8 for display panels is prepared (S1: preparation process). Further, when the display panel film 8 is manufactured, an ultraviolet absorbing layer forming paint 87 ′ for forming the ultraviolet absorbing layer 87, a pressure roller R1 for applying the ultraviolet absorbing layer forming paint 87 ′, and a cylinder R2 are provided. Gravure printing machine capable of performing gravure printing, pattern layer forming paint 81 ', diffusion layer forming paint 83', ultraviolet absorbing layer forming paint 87 ', ink reservoir, squeegee S, mold for storing each of these paints Prepare a frame W and the like.

  Next, a UV-absorbing layer forming coating 87 ′ is applied to the first surface 85 a of the substrate 85 using a gravure printing machine. The pressure roller R1 rotates counterclockwise, and the cylinder R2 rotates clockwise. As a result, the ultraviolet absorbing layer forming coating 87 'in the ink reservoir attached to the cylinder R2 is applied to the first surface 85a of the substrate 85 (S2: UV absorbing layer forming coating application step).

  Next, the ultraviolet absorbing layer forming coating 87 ′ of the member obtained in step S2 is dried to obtain a laminate in which the ultraviolet absorbing layer 87 is laminated on the first surface 85a of the substrate 85 (S3: drying step). ).

  Next, using a gravure printing machine capable of performing gravure printing, the diffusion layer forming coating 83 ′ is applied to the second surface 85 b of the substrate 85 in the laminate obtained in step S <b> 3. As a result, the diffusion layer forming coating 83 'in the ink reservoir attached to the cylinder R2 is applied to the second surface 85b of the substrate 85 (S4: diffusion layer forming coating application step).

  Next, the diffusion layer forming coating 83 ′ obtained in step S <b> 4 is dried to obtain a laminate in which the diffusion layer 83 is laminated on the first surface 85 a of the substrate 85 (S <b> 5: drying step).

  Next, in the laminate obtained in step S5, a picture layer forming paint 81 'is further applied on the diffusion layer 83 by screen printing. The mold W is placed on the laminate obtained in step S5, the squeegee S is scanned in a predetermined direction, and the pattern layer forming paint 81 ′ is applied on the diffusion layer 83 (S6: pattern layer forming). Paint coating process).

  Next, by drying the pattern layer forming paint 81 ′ of the member obtained in step S6, for the display panel, which is a laminate in which the pattern layer 81, the diffusion layer 83, the base material 85, and the ultraviolet absorbing layer 87 are stacked. A film 8 is obtained (S7: drying step). And the manufacturing process of the film 8 for display panels in which the pattern layer 81, the diffused layer 83, the base material 85, and the ultraviolet absorption layer 87 were laminated | stacked in this order is complete | finished.

  In this way, the display panel film 8 can be manufactured by selectively performing at least gravure printing and screen printing. Therefore, for example, screen printing may be performed in steps S2 and S4, gravure printing may be performed in step S6, or all of steps S2, S4, and S6 may be performed by screen printing or gravure printing. If there is a known printing method other than gravure printing and screen printing without impairing the effects of the present invention, the display panel film 8 may be manufactured using the printing method.

[Evaluation results]
The evaluation result using the film for display panels of Experimental Examples 1-6 is shown.

  FIG. 7 is a diagram showing the evaluation results of the display panel film.

  In Experimental Examples 1 to 6, each display panel film prepared for each of Experimental Examples 1 to 6 was fixed on the exit surface of the light guide plate, and the light source was turned on. In this state, the luminance average value, weather resistance, yellowness, and visibility were evaluated on the light exit surface of the display panel film. The light emission surface of the display panel film is a surface on the Y axis plus direction side of the display panel film.

  First, these evaluations will be described. In Experimental Examples 1 to 6, the average luminance value L of light emitted from the light emission surface of the display panel film was measured. A flat luminance meter was used to measure the average luminance value. When the reference of the luminance average value L was 150 ≦ L <300 and the luminance average value L was within this range, it was evaluated that the luminance unevenness of the light emitted from the display panel film was suppressed.

Next, in Experimental Examples 1 to 6, the color difference ΔE was measured in order to evaluate the weather resistance of the display panel film. For the measurement of the color difference ΔE, a light resistance test was performed using a high energy xenon fade meter. In the light resistance test, the irradiation time was 135 hours, the temperature was 60 ° C., the relative humidity was 50%, and the irradiance was 162 W / m ² . When the reference of the color difference ΔE was ΔE <3 and the color difference ΔE satisfying this condition, the weather resistance of the display panel film was evaluated as good.

  Next, in Experimental Examples 1 to 6, in order to evaluate the yellowness of the film for a display panel, the yellowness b ′ in a certain state was measured with reference to the b value in the state without the ultraviolet absorbing layer, and b Yellowness Δb was measured from '-b. The standard of the yellowness Δb was set to Δb <3, and if the yellowness Δb satisfying this condition was satisfied, the yellowness of the display panel film was evaluated as good.

  Next, in Experimental Examples 1 to 6, in order to evaluate the visibility of the display panel film, the glossiness G on the light emission surface side of the display panel film was measured. When the standard of glossiness G at 60 degrees was G <20, and the glossiness G satisfying this condition, the glossiness of the display panel film was evaluated as good.

  Next, the display panel film used in Experimental Examples 1 to 6 will be described.

  In the diffusion layer of the display panel film of Experimental Example 1, 100 parts by weight of acrylic resin WAL-567 (refractive index 1.49 manufactured by DIC) and benzoguanamine resin particle posters (refractive index 1.66 manufactured by Nippon Shokubai, average particle size 2 μm). ) Was added, diluted with ethyl acetate so that the solid content was 30%, and stirred to obtain a diffusion layer forming coating material 1. In the pattern layer of the display panel film of Experimental Example 1, SG700 (Seiko Advance Green) was used as the pattern layer forming paint. In addition, in the ultraviolet absorbing layer of the display panel film of Experimental Example 1, 8.5 parts by weight of UV absorbing layer forming coating KEMISORB73 and light-resistant stabilizer KEMISTAB62 are added to 100 parts by weight of acrylic resin WDL-787 (manufactured by DIC). Add 5 parts by weight, add 20 parts by weight of silica particles (Silicia 356RC, average particle size 3.5 μm, manufactured by Fuji Silysia) to give surface irregularities, and dilute and stir with ethyl acetate to a solid content of 25%. This was designated as UV-absorbing layer-forming coating material 1.

  The diffusion layer in the display panel film of Experimental Example 1 was printed with a gravure printing machine so that the dry film thickness would be 3 μm on one side of a PET film (Toyobo A4300) having a thickness of 125 μm. Then, the diffusion layer forming paint 1 is printed on the opposite PET surface with a gravure printing machine so that the dry film thickness is 7 μm, and the dry film thickness is 3 μm on the diffusion layer by the pattern layer forming paint. It was printed and manufactured.

  The diffusion layer and the pattern layer in the display panel film of Experimental Example 2 are the same as the diffusion layer and the pattern layer in the display panel film of Experimental Example 1. In the ultraviolet absorbing layer of the display panel film of Experimental Example 2, 10 parts by weight of silica particle silicia 356RC (manufactured by Fuji Silysia average particle size 3.5 μm) is added to 100 parts by weight of acrylic resin G13 (manufactured by Nippon Shokubai Co., Ltd.). The UV absorbing layer-forming coating material 2 was diluted and stirred with ethyl acetate so that the ratio was 25%.

  The display panel film of Experimental Example 2 was manufactured using the ultraviolet absorbing layer forming coating 2 instead of using the ultraviolet absorbing layer forming coating 1 in the manufacture of the display panel film of Experimental Example 1.

  The pattern layer in the display panel film of Experimental Example 3 is the same as the pattern layer in the display panel film of Experimental Example 1. In the diffusion layer of the film for display panel of Experimental Example 3, 100 parts by weight of acrylic resin WAL-567 (refractive index 1.49 manufactured by DIC) and benzoguanamine resin particle poster M05 (refractive index 1.66 manufactured by Nippon Shokubai, average particle size 5 μm). ) Was added, diluted with ethyl acetate to a solid content of 30%, and stirred to obtain Diffusion Layer-Forming Paint 3. In the ultraviolet absorbing layer of the display panel film of Experimental Example 3, 20 parts by weight of acrylic particles MBX-2H (Sekisui Plastics Co., Ltd. average particle size 2.0 μm) are added to 100 parts by weight of acrylic resin G13 (manufactured by Nippon Shokubai). The coating material for forming an ultraviolet absorbing layer 3 was diluted and stirred with ethyl acetate so that the solid content was 25%.

  In the display panel film of Experimental Example 3, the UV absorbing layer-forming coating 3 is printed on one side of a 125 μm thick PET film (Toyobo A4300) with a gravure printing machine so that the dry film thickness is 3 μm, and vice versa. Print the diffusion layer forming coating 3 on the PET surface on the side with a gravure printing machine so that the dry film thickness becomes 7 μm, and print on the diffusion layer with the pattern layer forming paint so that the dry film thickness becomes 3 μm. Manufactured.

  The display panel film of Experimental Example 3 uses the diffusion layer forming paint 3 and the UV absorbing material instead of using the UV absorbing layer forming paint 1 and the diffusion layer forming paint 1 in the manufacture of the display panel film of Experimental Example 1. Manufactured with layer-forming paint 3. Moreover, it printed so that the film thickness of an ultraviolet absorption layer might be set to 5 micrometers. Except for these points, the display panel film of Experimental Example 3 was manufactured by the same manufacturing method as the display panel film of Experimental Example 1.

  The display panel film of Experimental Example 4 is the same as the display panel film of Experimental Example 1 except that the ultraviolet absorbing layer is not formed.

  The display panel film of Experimental Example 4 is the production of the display panel film of Experimental Example 1. A dry film of the diffusion layer forming paint 1 on one side of a 125 μm thick PET film (A4300, manufactured by Toyobo Co., Ltd.) using a gravure printer. The film was printed so as to have a thickness of 7 μm, and was printed on the diffusion layer with a paint for forming a picture layer so that the dry film thickness was 3 μm.

  In the display panel film of Experimental Example 5, the diffusion layer is the same as the diffusion layer of the display panel film of Experimental Example 3, and the pattern layer is the same as the pattern layer of the display panel film of Experimental Example 1. In the ultraviolet absorbing layer of the display panel film of Experimental Example 5, 25 parts by weight of UV absorbing layer forming coating TINUVIN477 and 5 parts by weight of light-resistant stabilizer KEMISTAB62 are added to 100 parts by weight of acrylic resin WDL-787 (manufactured by DIC). 20 parts by weight of acrylic particles MBX-2H (Sekisui Plastics Co., Ltd. average particle size 2.0 μm) were added, diluted with ethyl acetate so that the solid content was 25%, and stirred to form an ultraviolet absorbing layer. Paint 4 was obtained.

  The display panel film of Experimental Example 5 is the same as the display panel film of Experimental Example 1 except that the display panel film is manufactured using the diffusion layer forming paint 3 and the ultraviolet absorbing layer forming paint 4.

  The pattern layer and the ultraviolet absorption layer in the display panel film of Experimental Example 6 are the same as the pattern layer and the ultraviolet absorption layer in the display panel film of Experimental Example 1. In the display panel film of Experimental Example 6, the light diffusion layer is made of acrylic resin WAL-567 (refractive index 1.49 manufactured by DIC) in 100 parts by weight, and acrylic particles SSX-101 (refractive index 1.49 manufactured by Sekisui Plastics Co., Ltd.). Was added with 80 parts by weight, diluted with ethyl acetate so that the solid content was 30%, and the resulting mixture was stirred to obtain Diffusion Layer-Forming Paint 4.

  The display panel film of Experimental Example 6 is the same as the display panel film of Experimental Example 1 except that the display panel film is manufactured with the diffusion layer forming coating 4.

Surface roughness Ra (μm) of the diffusion layer using the display panel film of Experimental Examples 1 to 6, light transmittance% with respect to wavelength 380 nm, light transmittance% with respect to wavelength 400 nm, and surface roughness of ultraviolet absorbing layer Based on the thickness Ra (μm), the front luminance, weather resistance, yellowness, and visibility were evaluated. Visibility is a viewpoint of the glossiness of the film surface for display panels. Note that A shown in FIG. 7 indicates that the front luminance is less than 150 (cd / m ² ), and B shown in FIG. 7 indicates that the front luminance is 300 (cd / m ² ) or more.

  From the evaluation results of the front luminance, weather resistance, yellowness, and visibility, in this embodiment, the surface roughness Ra of the diffusion layer 83 is 0.5 μm or more and 3.0 μm or less, and the wavelength of light of the ultraviolet absorption layer 87 is 380 nm. The transmittance with respect to the wavelength of light of the ultraviolet absorbing layer 87 is not less than 60% and the surface roughness Ra of the ultraviolet absorbing layer 87 is not less than 0.5 μm and not more than 3.0 μm.

[Function and effect]
Next, the effect of the manufacturing method of the display panel film 8 and the display panel film 8 in this Embodiment is demonstrated.

  As described above, the light emitted from the light source 51 enters and exits the display panel film 8 according to the present embodiment. The display panel film 8 includes a pattern layer 81, a diffusion layer 83, a base material 85 that is a translucent film, and an ultraviolet absorption layer 87. Further, in the display panel film 8, the pattern layer 81, the diffusion layer 83, the base material 85, and the ultraviolet absorption layer 87 are laminated in this order in a direction away from the light source 51 side. The diffusion layer 83 contains a resin and light diffusing particles having a refractive index different from that of the resin, and has a surface roughness of 0.5 μm or more and 3.0 μm or less. The ultraviolet absorbing layer 87 has a light transmittance of 50% or less for a light wavelength of 380 nm and a light transmittance of 60% or more for a light wavelength of 400 nm.

  According to this, in the display panel film 8, the pattern layer 81, the diffusion layer 83, the base material 85, and the ultraviolet absorption layer 87 are laminated in this order in a direction away from the light source 51 side. The ultraviolet absorbing layer 87 has a light transmittance of 50% or less for a light wavelength of 380 nm and a light transmittance of 60% or more for a light wavelength of 400 nm. For this reason, it can suppress that the brightness | luminance of the light radiate | emitted from the film 8 for display panels falls.

  Moreover, since the ultraviolet absorption layer 87 is laminated | stacked on the outer side of the illuminating device 1 on the opposite side to the light source 51 side, the display panel film 8 suppresses deterioration of the display panel film 8 due to ultraviolet rays. Therefore, it is excellent in weather resistance. Moreover, deterioration, such as yellowing of the film 8 for display panels which arises by ultraviolet irradiation, can be suppressed. For this reason, the film 8 for display panels is excellent in quality.

  The diffusion layer 83 contains a resin and light diffusing particles having a refractive index different from that of the resin, and has a surface roughness of 0.5 μm or more and 3.0 μm or less. For this reason, the light emitted from the emission surface 73 of the light guide plate 7 is diffused by the diffusion layer forming coating 83 ′ and the surface roughness of the diffusion layer 83 and emitted from the display panel film 8. For this reason, the film 8 for display panels can radiate | emit the light by which the brightness spot was suppressed.

  Therefore, the display panel film 8 is excellent in quality and can suppress luminance unevenness.

  Moreover, the illuminating device 1 which concerns on this Embodiment is provided with the light source 51, the film 8 for display panels, and the light guide plate 7 which guides the light which the light source 51 emitted, and irradiates the film 8 for display panels.

  Moreover, the manufacturing method of the film 8 for display panels which concerns on this Embodiment manufactures the film 8 for display panels using selectively gravure printing and screen printing at least. In the manufacturing method of the film 8 for display panels, the ultraviolet absorption layer 87 is applied to the first surface 85a of the substrate 85, the coated ultraviolet absorption layer 87 is dried, and the opposite side of the substrate 85 from the first surface 85a. The diffusion layer 83 is applied to the second surface 85b, the applied diffusion layer 83 is dried, the pattern layer 81 is further applied to the diffusion layer 83, and the applied pattern layer 81 is dried.

  Also in these cases, the same effects as described above are obtained.

  In addition, in the display panel film 8 according to the present embodiment, the pattern layer 81 of the ultraviolet absorption layer 87, the diffusion layer 83, and the pattern layer 81 is applied last.

  According to this, as shown in step S5 of FIG. 6, if a laminated body in which the ultraviolet absorbing layer 87, the diffusion layer 83, and the pattern layer 81 are coated on the base material 85 is prepared, according to the demand and application. The pattern layer 81 can be applied to the laminate as appropriate. For this reason, the loss which arises by manufacture of the film 8 for display panels can be reduced compared with the case where the ultraviolet absorption layer 87 is applied last, for example.

  In the display panel film 8 according to the present embodiment, the ultraviolet absorbing layer 87 has a light transmittance of 30% or less for a light wavelength of 380 nm and a light transmittance of 70% or more for a light wavelength of 400 nm. .

  According to this, in the film 8 for display panels, the brightness | luminance of the light radiate | emitted from the film 8 for display panels can fall, or yellowing can be suppressed.

  In the display panel film 8 according to the present embodiment, the surface roughness of the ultraviolet absorbing layer 87 is not less than 0.5 μm and not more than 3.0 μm.

  Usually, when the display panel film 8 is viewed from the outside, visibility may be deteriorated due to reflection of external light. However, in the display panel film 8, since the surface roughness of the ultraviolet absorbing layer 87 is not less than 0.5 μm and not more than 3.0 μm, external light is diffused in the ultraviolet absorbing layer 87. For this reason, the fall of the visibility by reflection of external light can be suppressed. In the display panel film 8, the surface hardness and the sliding resistance on the light exit surface of the display panel film 8 are improved.

  In the display panel film 8 according to the present embodiment, the ultraviolet absorbing layer 87 contains at least one of a surfactant, an ion conductive polymer, and a conductive metal oxide.

  According to this, since the surface resistance value of the surface on the Y-axis direction side of the display panel film 8 can be reduced in the display panel film 8, the ultraviolet absorbing layer in contact with the outside of the display panel film 8 It is possible to suppress dust and the like from adhering to 87.

  In the display panel film 8 according to the present embodiment, the light diffusing particles are benzoguanamine-based spherical resin particles.

  According to this, since the film 8 for display panels can diffuse the light which permeate | transmits the diffusion layer 83, it is excellent in the luminance characteristic. For this reason, in the film 8 for display panels, the fall of visibility can be suppressed.

  In the display panel film 8 according to the present embodiment, the surface roughness of the pattern layer 81 is 1.0 μm or more and 5.0 μm or less.

  According to this, the display panel film 8 is capable of diffusing the light transmitted through the pattern layer 81, and thus has excellent luminance characteristics. For this reason, in the film 8 for display panels, the fall of visibility can be suppressed.

(Other variations)
The display panel film, the display panel film manufacturing method, and the lighting device according to the embodiment of the present disclosure have been described above, but the embodiment of the present disclosure is not limited to the above-described embodiment.

  For example, according to the above embodiment, the display panel film, the display panel film manufacturing method, and the lighting device are housed in the housing, but the present invention is not limited thereto. For example, it may be provided in a state of overlapping with and contacting the outer peripheral edge of the housing on the Y axis plus direction side.

  As described above, the display panel film, the display panel film manufacturing method, and the lighting device according to one or more aspects have been described based on the embodiments. However, the embodiments of the present disclosure are limited to the plurality of aspects. Is not to be done. Unless it deviates from the gist of the present disclosure, various modifications conceived by those skilled in the art have been made in this embodiment, and forms constructed by combining components in different embodiments are also within the scope of one or more aspects. May be included.

DESCRIPTION OF SYMBOLS 1 Illuminating device 7 Light guide plate 8 Film for display panels 51 Light source 81 Picture layer 83 Diffusion layer 85 Base material 87 Ultraviolet absorption layer

Claims (9)

A display panel film from which light emitted from a light source enters and exits,
A pattern layer, a diffusion layer, a base material that is a translucent film, and an ultraviolet absorption layer,
In the direction away from the light source side, the pattern layer, the diffusion layer, the base material and the ultraviolet absorption layer are laminated in this order,
The diffusion layer is
A resin and light diffusing particles having a refractive index different from that of the resin,
The surface roughness is 0.5 μm or more and 3.0 μm or less,
The ultraviolet absorbing layer has a transmittance of 50% or less for a light wavelength of 380 nm and a transmittance of 60% or more for a light wavelength of 400 nm. The display panel film according to claim 1, wherein the ultraviolet absorbing layer has a light transmittance of 30% or less for a light wavelength of 380 nm and a light transmittance of 70% or more for a light wavelength of 400 nm. The film for display panels according to claim 1, wherein the ultraviolet absorbing layer has a surface roughness of 0.5 μm or more and 3.0 μm or less. The display panel film according to claim 1, wherein the ultraviolet absorbing layer contains at least one of a surfactant, an ion conductive polymer, and a conductive metal oxide. The film for display panels according to claim 1, wherein the light diffusing particles are benzoguanamine-based spherical resin particles. The film for display panels according to claim 1, wherein the pattern layer has a surface roughness of 1.0 μm or more and 5.0 μm or less. It is a manufacturing method of the film for display panels which manufactures the film for display panels of any one of Claims 1-6 by selectively performing gravure printing and screen printing at least,
Applying the ultraviolet absorbing layer to the first surface of the substrate;
Dry the coated UV absorbing layer,
Coating the diffusion layer on the second surface opposite to the first surface of the substrate;
The coated diffusion layer is dried,
Further applying the pattern layer to the diffusion layer,
A method for producing a film for a display panel, wherein the coated image layer is dried. The manufacturing method of the film for display panels of Claim 7 which coats the said pattern layer last among the said ultraviolet absorption layer, the said diffusion layer, and the said pattern layer. The light source;
A film for a display panel according to any one of claims 1 to 6,
An illumination device comprising: a light guide plate that guides light emitted from the light source and irradiates the display panel film.

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