Light-blocking member, assembly sheet, and method for manufacturing light-blocking member

Abstract

A light-blocking member 1 comprises a metal core layer 2 and a resin layer 3. The resin layer 3 covers the entirety of both surfaces S11 and S12 of the core layer 2 in the thickness direction of the core layer 2. The 5° regular reflectance of visible light of the resin layer 3 is lower than the 5° regular reflectance of visible light of the surfaces S11, S12 of the core layer 2.

Description

Light-shielding member, assembly sheet, and method for manufacturing light-shielding member

[0001] The present invention relates to a light-shielding member, an assembly sheet, and a method for manufacturing the light-shielding member.

[0002] 2. Description of the Related Art Conventionally, a light-shielding member having an optical multilayer film on the surface of a substrate has been known (see, for example, Patent Document 1 below).

[0003] The substrate is made of resin. The optical multilayer film is composed of a light-absorbing layer and a dielectric layer. The light-absorbing layer and the dielectric layer are made of metal or metal oxide.

[0004] International Publication No. 2021 / 193652

[0005] In the light-shielding member described in the above-mentioned Patent Document 1, an optical multilayer film made of a metal or metal oxide is formed on the surface of a base material made of resin.

[0006] Therefore, it is difficult to achieve both rigidity and durability in the light blocking member.

[0007] The present invention provides a light-shielding member, an assembly sheet, and a method for manufacturing a light-shielding member that can achieve both rigidity and durability.

[0008] The present invention [1] includes a light-shielding member comprising a metal core layer and a resin layer covering the entire surfaces of both sides of the core layer in the thickness direction of the core layer, the resin layer having a 5° specular reflectance of visible light lower than that of the surfaces of the core layer.

[0009] According to this configuration, the core layer is made of metal.

[0010] Therefore, the rigidity of the light blocking member can be ensured.

[0011] Furthermore, the core layer is covered with a resin layer having a 5° specular reflectance of visible light lower than that of the surface of the core layer (i.e., a resin layer having lower reflectance than the core layer).

[0012] Therefore, the resin layer can protect the core layer and suppress light reflection.

[0013] As a result, it is possible to achieve both rigidity and durability of the light blocking member.

[0014] The present invention [2] includes the light-shielding member according to the above [1], wherein the resin layer has a 5° specular reflectance of visible light of 1.0% or less.

[0015] According to this configuration, the resin layer can reliably suppress light reflection.

[0016] The present invention [3] includes the light-shielding member according to the above [1] or [2], wherein the resin layer covers the side surface of the core layer in a direction perpendicular to the thickness direction.

[0017] According to this configuration, the resin layer can protect the side surfaces of the core layer while suppressing light reflection on the side surfaces of the light-shielding member.

[0018] The present invention [4] includes the light-shielding member according to the above [3], wherein the resin layer covers the entire side surface of the core layer.

[0019] According to this configuration, the resin layer can more reliably suppress the reflection of light on the side surfaces of the light-shielding member.

[0020] The present invention [5] includes the light-shielding member of the above [3], wherein the core layer has a main body portion having the surface and the side surface, and a protrusion portion protruding from the side surface of the main body portion in the perpendicular direction, and the protrusion portion is exposed from the resin layer.

[0021] The present invention [6] includes the light-shielding member according to any one of the above [1] to [5], wherein the resin layer contains a black pigment.

[0022] The present invention [7] includes the light-shielding member according to any one of the above [1] to [6], wherein the resin layer contains a filler.

[0023] The present invention [8] includes the light-shielding member of any one of the above [1] to [7], wherein the resin layer is an outermost layer that constitutes the surface of the light-shielding member.

[0024] The present invention [9] includes an assembly sheet comprising the light-shielding member of the above [5], a frame arranged at a distance from the light-shielding member, and a joint connecting the light-shielding member and the frame, wherein the joint is made of the same metal as the core layer and is continuous with the protrusion.

[0025] According to this configuration, the light blocking member can be handled while being supported by the frame via the joint, thereby improving the ease of handling of the light blocking member.

[0026] The present invention

[10] includes a method for manufacturing a light-shielding member according to any one of the above [1] to [8], which includes a core forming step of forming the core layer, and a coating step of coating the core layer with the resin layer by electrodeposition coating.

[0027] According to this method, the light-shielding member can be manufactured by a simple process of electrodeposition coating on the core layer.

[0028] According to the light-shielding member of the present invention, it is possible to achieve both rigidity and durability of the light-shielding member.

[0029] FIG. 1 is a perspective view of a light-shielding member according to one embodiment of the present invention. FIG. 2 is a cross-sectional view of the light-shielding member shown in FIG. 1 taken along the line A-A. FIGS. 3A to 3C are process diagrams illustrating the manufacturing process of the light-shielding member shown in FIG. 1 . FIG. 3A illustrates a process for preparing a metal substrate, FIG. 3B illustrates a process for etching the substrate to form a core layer (core formation process), and FIG. 3C illustrates a process for forming a resin layer on the surface of the core layer by electrodeposition coating (coating process). FIGS. 4A to 4C are process diagrams illustrating the manufacturing process of Modification (1). FIG. 4A illustrates a process for forming a seed layer on a metal substrate, FIG. 4B illustrates a process for forming a core layer on the seed layer by plating (core formation process), FIG. 4C illustrates a process for removing the substrate and seed layer by etching, and FIG. 4D illustrates a process for forming a resin layer on the surface of the core layer by electrodeposition coating (coating process). FIG. 5 is a perspective view of a light-shielding member according to Modification (2). FIG. 6A is a plan view of the light-shielding member shown in FIG. 5. Fig. 6B is a cross-sectional view of the light blocking member taken along line BB of Fig. 6A Fig. 7 is a plan view of an assembly sheet of modified example (3).

[0030] 1. Light-blocking member As shown in Figure 1, the light-blocking member 1 has a flat plate shape. The light-blocking member 1 has a surface S1 on one side and a surface S2 on the other side in the thickness direction. The light-blocking member 1 has a side surface S3 in an orthogonal direction perpendicular to the thickness direction. The light-blocking member 1 extends in the orthogonal direction. The light-blocking member 1 blocks at least visible light.

[0031] The light-shielding member 1 has a visible light transmittance (JIS K 7375:2008) in the thickness direction of, for example, 1.0% or less, preferably 0.01% or less, or more preferably 0%.

[0032] The 5° specular reflectance of visible light on each surface (surfaces S1, S2 and side surface S3) of the light-shielding member 1 is, for example, 1.0% or less, preferably 0.5% or less, and for example, 0% or more. The "5° specular reflectance of visible light" is the average value of the reflectance of visible light with a wavelength of 500 nm to 600 nm.

[0033] The flexural modulus (JIS K 7171:2022) of the light-shielding member 1 is, for example, 10 GPa or more, or preferably 50 GPa or more, and for example, 250 GPa or less.

[0034] The thickness T of the light-shielding member 1 is, for example, 10 μm or more, preferably 20 μm or more, more preferably 30 μm or more, and for example, 100 μm or less, preferably 50 μm or less, more preferably 40 μm or less. The thickness T of the light-shielding member 1 may be, for example, 10 μm to 100 μm, 20 μm to 50 μm, or 30 μm to 40 μm.

[0035] As shown in FIG. 2, the light-shielding member 1 includes a core layer 2 and a resin layer 3 .

[0036] (1) Core Layer The core layer 2 is disposed approximately in the center of the light-shielding member 1 in the thickness direction. The core layer 2 extends in the perpendicular direction. The core layer 2 has a flat plate shape. The core layer 2 has a surface S11 on one side and a surface S12 on the other side in the thickness direction. The core layer 2 has a side surface S13 in the perpendicular direction.

[0037] The thickness T1 of the core layer 2 is, for example, 5 μm or more, preferably 10 μm or more, and for example, 70 μm or less, preferably 30 μm or less. When the thickness T1 of the core layer 2 is equal to or more than the above lower limit, the rigidity of the light-shielding member 1 can be ensured. The thickness T1 of the core layer 2 may be 5 μm to 70 μm, or 10 μm to 30 μm.

[0038] When the thickness T of the light-shielding member 1 is taken as 100%, the thickness T1 of the core layer 2 is, for example, 30% or more, preferably 40% or more, and for example, 70% or less, preferably 50% or less. When the ratio of the thickness T1 of the core layer 2 to the thickness T of the light-shielding member 1 is equal to or greater than the above lower limit, the rigidity of the light-shielding member 1 can be ensured. The ratio of the thickness T1 of the core layer 2 to the thickness T of the light-shielding member 1 may be 30% to 70% or 40% to 50%.

[0039] The 5° specular reflectance of visible light on each surface (surfaces S11, S12 and side surface S13) of the core layer 2 is, for example, 10% to 90%.

[0040] The core layer 2 is made of a metal. Examples of materials for the core layer 2 include copper, copper alloys, stainless steel, aluminum, titanium, nickel, tantalum, and magnesium. Preferred materials for the core layer 2 include copper and stainless steel.

[0041] (2) Resin Layer The resin layer 3 covers the core layer 2. The resin layer 3 covers the surfaces S11 and S12 of the core layer 2 in the thickness direction. The resin layer 3 covers the entire surfaces S11 and S12 of the core layer 2. In other words, the resin layer 3 covers the entire surfaces S1 and S2 of the core layer 2 in the thickness direction of the core layer 2. The resin layer 3 covers the side surface S13 of the core layer 2 in the perpendicular direction. The resin layer 3 preferably covers the entire side surface S13 of the core layer 2. The resin layer 3 is preferably the outermost layer. The resin layer 3 constitutes the surfaces S1 and S2 and the side surface S3 of the light-shielding member 1.

[0042] The 5° specular reflectance of visible light of the resin layer 3 is lower than the 5° specular reflectance of visible light of the surface of the core layer 2. The 5° specular reflectance of visible light of the resin layer 3 is, for example, 1.0% or less, preferably 0.5% or less, and for example, 0% or more.

[0043] The thickness T2 of the resin layer 3 is, for example, 3 μm or more, preferably 5 μm or more, and for example, 20 μm or less, preferably 15 μm or less. When the thickness T2 of the resin layer 3 is equal to or greater than the above lower limit, the durability of the light-shielding member 1 can be improved. The thickness T2 of the resin layer 3 may be 3 μm to 20 μm, or 5 μm to 15 μm.

[0044] The thickness T2 of the resin layer 3 is thinner than the thickness T1 of the core layer 2. When the thickness T1 of the core layer 2 is taken as 100%, the thickness T2 of the resin layer 3 is in the range of, for example, 40% to 90%, or preferably 50% to 70%.

[0045] The surface roughness of the resin layer 3 is, for example, 0.1 μm or more, preferably 1.0 μm or more, and for example, 10.0 μm or less.

[0046] The resin layer 3 contains a resin, a pigment, and a filler.

[0047] Examples of the resin include acrylic resin, epoxy resin, polyimide, and polyamide, and preferably acrylic resin.

[0048] The proportion of the resin in the resin layer 3 is, for example, 20 mass % or more, preferably 30 mass % or more, and for example, 80 mass % or less, preferably 70 mass % or less.

[0049] Examples of the pigment include black pigments and gray pigments. Preferably, the pigment is a black pigment. Preferably, the black pigment is a black pigment and a black dye. Preferably, the black pigment is a carbon black or a titanium-based pigment. Preferably, the black dye is a mixture of dyes such as phthalocyanine blue, phthalocyanine green, monoazo yellow, disazo yellow, benzimidazolone yellow, quinacridone red, monoazo red, boriazo red, and perylene red. More preferably, the pigment is a black pigment, and even more preferably, carbon black.

[0050] The proportion of the dye in the resin layer 3 is, for example, 0.1 mass % or more, preferably 0.5 mass % or more, and for example, 20 mass % or less, preferably 10 mass % or less.

[0051] The number of parts of the dye per 100 parts by mass of the resin is, for example, 1 part by mass or more, preferably 5 parts by mass or more, and for example, 50 parts by mass or less, preferably 30 parts by mass or less.

[0052] Examples of the filler include acrylic microgel and silica, and preferably, acrylic microgel.

[0053] The average particle size of the filler is measured by a laser diffraction scattering method and is, for example, 1.0 μm or more, preferably 5.0 μm or more, and for example, 20.0 μm or less.

[0054] The proportion of the filler in the resin layer 3 is, for example, 1 mass % or more, preferably 5 mass % or more, and for example, 50 mass % or less, preferably 30 mass % or less.

[0055] The number of parts of the filler per 100 parts by mass of the resin is, for example, 5 parts by mass or more, preferably 10 parts by mass or more, and for example, 50 parts by mass or less, preferably 40 parts by mass or less.

[0056] 2. Manufacturing Method of Light-Shielding Member Next, a manufacturing method of the light-shielding member 1 will be described.

[0057] As shown in FIG. 3A, the method for manufacturing the light-shielding member 1 includes a core-forming step (see FIGS. 3A and 3B) and a coating step (see FIG. 3C).

[0058] (1) Core Forming Step As shown in Figures 3A and 3B, in the core forming step, the core layer 2 is formed. To form the core layer 2, for example, a substrate M made of the material of the core layer 2 described above is etched to obtain the core layer 2. More specifically, the portion where the core layer 2 is to be formed is covered with an etching resist, and the substrate M exposed from the etching resist is removed by etching. In this way, the core layer 2 is obtained.

[0059] (2) Coating Step Next, as shown in Fig. 3C, in the coating step, the core layer 2 obtained in the core formation step is coated with a resin layer 3. Methods for coating the core layer 2 with the resin layer 3 include, for example, electrodeposition coating and dipping. Preferably, in the coating step, the core layer 2 is coated with the resin layer 3 by electrodeposition coating, taking advantage of the fact that the core layer 2 is made of metal.

[0060] 3. Effects (1) As shown in FIG. 2 , the light-shielding member 1 includes a metal core layer 2 and a resin layer 3 that covers the core layer 2 .

[0061] Therefore, the core layer 2 can ensure the rigidity of the light blocking member 1 .

[0062] Furthermore, the core layer 2 is covered with a resin layer 3 having a 5° specular reflectance of visible light lower than that of the surface of the core layer 2 (i.e., a resin layer 3 having lower reflectance than the core layer 2).

[0063] Therefore, the resin layer 3 can protect the core layer 2 while suppressing light reflection.

[0064] As a result, the light blocking member 1 can have both high rigidity and durability.

[0065] (2) In the light-shielding member 1, the resin layer 3 has a 5° specular reflectance of visible light of 1.0% or less.

[0066] Therefore, the resin layer 3 can reliably suppress light reflection.

[0067] (3) According to the light-shielding member 1, as shown in FIG. 2, the resin layer 3 covers the side surface S13 of the core layer 2.

[0068] Therefore, the resin layer 3 can protect the side surface S13 of the core layer 2 while suppressing light reflection at the side surface S3 of the light-shielding member 1.

[0069] (4) According to the light-shielding member 1, as shown in FIGS. 1 and 2, the resin layer 3 covers the entire side surface S13 of the core layer 2.

[0070] Therefore, the resin layer 3 can more reliably suppress the reflection of light on the side surface S3 of the light-shielding member 1.

[0071] (5) As shown in Figures 3A to 3C, the manufacturing method of the light-shielding member 1 includes a core formation process (see Figures 3A and 3B) for forming a core layer 2, and a coating process (see Figure 3C) for coating the core layer 2 with a resin layer 3 by electrocoating.

[0072] Therefore, by taking advantage of the fact that the core layer 2 is made of metal, the light-shielding member 1 can be manufactured by a simple process of electrodeposition coating the core layer 2.

[0073] 4. Modifications Modifications will be described below. In the modifications, the same components as those in the above-described embodiment are denoted by the same reference numerals, and the description thereof will be omitted.

[0074] (1) As shown in FIGS. 4A to 4C, in the core formation step, the core layer 2 may be formed by electrolytic plating.

[0075] 4A, a seed layer M2 is first formed on a substrate M1 by, for example, sputtering. The substrate M1 is made of a metal that can be removed by etching. Examples of materials for the substrate M1 include stainless steel. Examples of materials for the seed layer M2 include chromium, copper, nickel, titanium, and alloys thereof.

[0076] Next, as shown in Figure 4B, a plating resist R having an opening where the core layer 2 will be formed is formed on the seed layer M2, and the core layer 2 is formed on the seed layer M2 exposed from the plating resist R by electrolytic plating.

[0077] 4C, the substrate M1 and the seed layer M2 are removed by etching, thereby obtaining the core layer 2.

[0078] 4D, in the same manner as in the above-described embodiment, in the coating step, the core layer 2 is coated with the resin layer 3. Preferably, the core layer 2 is coated with the resin layer 3 by electrodeposition coating.

[0079] This modification also provides the same effects as those of the above embodiment.

[0080] (2) As shown in FIGS. 5 and 6A, the core layer 2 may have a main body portion 21 and protrusions 22.

[0081] The main body 21 extends in the orthogonal direction. The main body 21 has a flat plate shape. The main body 21 has a surface S11 on one side and a surface S12 on the other side in the thickness direction. The main body 21 has a side surface S13 in the orthogonal direction.

[0082] The protrusion 22 protrudes perpendicularly from the side surface S13 of the main body 21. In the protruding direction of the protrusion 22, an end face S31 of the protrusion 22 is exposed from the resin layer 3. The end face S31 of the protrusion 22 may be flush with the surface of the resin layer 3. The end face S31 of the protrusion 22 does not have to be flush with the surface of the resin layer 3. The protrusion 22 may be a remaining part of a joint J, which will be described in Modification Example (3) below.

[0083] When the area of ​​the side surface S3 of the light-shielding member 1 is taken as 100%, the area of ​​the end surface S31 of the protrusion 22 is, for example, 75% or less, preferably 50% or less, and for example, 1.0% or more. If the ratio of the area of ​​the end surface S31 of the protrusion 22 to the area of ​​the side surface S3 of the light-shielding member 1 is equal to or less than the above upper limit, excessive increase in light reflection at the side surface S3 can be suppressed.

[0084] This modification also provides the same effects as those of the above embodiment.

[0085] (3) As shown in Fig. 7 , in the manufacturing of the light-shielding member 1 described above, an assembly sheet 100 having a plurality of light-shielding members 1 may be manufactured. The assembly sheet 100 includes a plurality of light-shielding members 1, a frame F, and a plurality of joints J.

[0086] The frame F is disposed at a distance from the light blocking members 1. The frame F has, for example, a frame shape. The frame F is disposed around the plurality of light blocking members 1.

[0087] The joint J is disposed between the light blocking member 1 and the frame F. The joint J connects the light blocking member 1 and the frame F. The joint J is made of the same metal as the core layer 2. As shown in FIG. 6A , the joint J is continuous with the protrusion 22.

[0088] This modification also provides the same effects as those of the above embodiment.

[0089] Furthermore, in this modified example, a plurality of light blocking members 1 can be handled while being supported by the frame F via the joints J, thereby improving the ease of handling of the light blocking members 1.

[0090] (4) In the above-described embodiment, the light-shielding member 1 is composed of the core layer 2 and the resin layer 3, but the configuration of the light-shielding member 1 is not limited to the above-described embodiment. The light-shielding member 1 may include components other than the core layer 2 and the resin layer 3. For example, the light-shielding member 1 may have an adhesion layer disposed between the core layer 2 and the resin layer 3. The light-shielding member 1 may also have a cover layer that covers the resin layer 3. The cover layer may be a black metal layer. Examples of materials for the black metal layer include titanium, nickel, and chromium. The black metal layer may be formed by, for example, physical vapor deposition. Examples of physical vapor deposition include vacuum deposition and sputtering.

[0091] The present invention will be described in more detail below with reference to examples and comparative examples. It should be noted that the present invention is in no way limited to these examples and comparative examples. The specific numerical values ​​of the blending ratios (content ratios), physical property values, parameters, etc. used in the following description can be replaced with the upper limit (a numerical value defined as "equal to or less than") or lower limit (a numerical value defined as "equal to or more than") of the corresponding blending ratios (content ratios), physical property values, parameters, etc. described in the "Description of the Invention" above.

[0092] 1. Production of Test Pieces (1) Example 1 First, a core layer (thickness: 15 μm) made of stainless steel was prepared.

[0093] Next, a resin layer (thickness: 10 μm) was formed on the surface of the core layer by electrodeposition coating.

[0094] In this manner, test specimens were produced.

[0095] (2) Example 2 A test piece was produced in the same manner as in Example 1, except that a core layer (thickness: 15 μm) made of copper was used instead of the core layer made of stainless steel.

[0096] (3) Comparative Example A test piece was manufactured by forming a plating layer (thickness: 10 μm) made of chromium on the surface of a core layer (thickness: 15 μm) made of stainless steel.

[0097] 2. Evaluation of Durability The resin layer or plating layer of the test piece obtained in each of the Examples and Comparative Examples was rubbed (load: 100 g) with a needle (stainless steel, tip diameter φ: 2 mm), and it was observed whether the resin layer or plating layer peeled off from the core layer.

[0098] In both Example 1 and Example 2, no peeling of the resin layer was observed.

[0099] On the other hand, in the comparative example, the plating layer peeled off from the core layer.

[0100] From the above results, it was evaluated that Examples 1 and 2 have higher durability against friction than Comparative Example. Note that the above invention is provided as an exemplary embodiment of the present invention, but this is merely an example and should not be interpreted as limiting. Modifications of the present invention that are obvious to those skilled in the art are included in the scope of the claims below.

[0101] The light-shielding member of the present invention can be used to block visible light, for example.

[0102] REFERENCE SIGNS LIST 1 Light blocking member 2 Core layer 21 Main body 22 Protrusion 3 Resin layer 100 Assembly sheet S11 Surface of core layer S12 Surface of core layer S13 Side surface of core layer F Frame J Joint

Claims

1. A light-shielding member comprising: a metal core layer; and a resin layer covering the entire surface of both sides of the core layer in the thickness direction of the core layer, the resin layer having a 5° specular reflectance of visible light lower than that of the surfaces of the core layer.

2. The light-shielding member according to claim 1, wherein the 5° specular reflectance of the resin layer for visible light is 1.0% or less.

3. The light-shielding member according to claim 1, wherein the resin layer covers the side surfaces of the core layer in a direction perpendicular to the thickness direction.

4. The light-shielding member according to claim 3, wherein the resin layer covers the entire side surface of the core layer.

5. A light-shielding member as described in claim 3, wherein the core layer has a main body portion having the surface and the side surface, and a protrusion portion protruding from the side surface of the main body portion in the perpendicular direction, the protrusion portion being exposed from the resin layer.

6. The light-shielding member according to claim 1, wherein the resin layer contains a black pigment.

7. The light-shielding member according to claim 1, wherein the resin layer contains a filler.

8. The light-shielding member according to claim 1, wherein the resin layer is an outermost layer that constitutes the surface of the light-shielding member.

9. An assembly sheet comprising: a light-shielding member according to claim 5; a frame arranged at a distance from said light-shielding member; and a joint connecting said light-shielding member and said frame, said joint being made of the same metal as said core layer and being continuous with said protruding portion.

10. A method for manufacturing a light-shielding member according to claim 1, comprising: a core forming step of forming the core layer; and a coating step of coating the core layer with the resin layer by electrodeposition coating.

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