High brightness reflective sheet and backlight module

Abstract

The invention discloses a high-brightness reflective sheet and a backlight module, wherein the high-brightness reflective sheet comprises: a base film; a first adhesive layer, which is arranged on the surface of the base film corresponding to the light incident surface of the high-brightness reflective sheet; a silver-plated film, which comprises a first substrate and a silver-plated layer arranged on the first substrate, wherein the first substrate is attached to the first adhesive layer; a second adhesive layer, which is arranged on the silver-plated layer; a light-transmitting film, which is attached to the second adhesive layer; wherein the first adhesive layer has a thickness of 3 to 5 μm, and the base film, the first adhesive layer and the silver-plated film are combined into a fixed stack film with a total thickness of 41 to 43 μm; the second adhesive layer has a thickness of 3 to 5 μm, and the refractive index of the second adhesive layer 400 is 1.482 to 1.523; the light-transmitting film has a thickness of 37 to 39 μm, and the haze value of the light-transmitting film 500 is not greater than 1.0%, and the light transmittance of the light-transmitting film is greater than 88%. The high-brightness reflective sheet of the invention has high brightness and good reflection effect.

Description

Technical Field

[0001] The present invention relates to the technical field of optical films, and in particular to a high-brightness reflective sheet and a backlight module. Background Art

[0002] The backlight module is an important component of the liquid crystal display device. After the light source of the backlight module enters the light guide plate, the light source is provided to the LCD module upward, and the light is hit into the reflective sheet downward, and then rebounds back to the LCD module through the light guide plate. Therefore, a very important factor affecting the quality and quality of the backlight module is the light reflection utilization rate, that is, the brightness of the reflective film of the backlight module. At present, among the reflective sheets on the market, 3M's ESR reflective sheet is a reflective sheet with higher brightness. It uses polyester lamination technology to improve the brightness of the reflective sheet. Specifically, it uses film layers with different refractive indices to stack to produce optical reflection and improve brightness.

[0003] Since light has the property of sine wave (orthogonal wave), when light encounters an optical material made of stacked materials with different refractive indices and thicknesses, the way the light travels will change, for example, Figure 1 At the same time, the light waveform will change the state of the light wave due to loss, for example, the displacement of 1 / 4λ ahead or behind the original normal light wave in the direction of movement. The change of the state of the light wave, that is, when the light reaches the reflective layer of the reflector, different losses will be generated in the reflection direction and the penetration direction, thus affecting the brightness of the reflector. The existing reflector design penetrates PET and touches the silver layer for reflection. There is no optimization plan for the optical light path design. The two-layer composite film structure can no longer further improve the brightness. Summary of the invention

[0004] The technical problem solved by the present invention is to provide a high-brightness reflector and backlight module in view of the defects existing in the above-mentioned prior art, so as to at least solve the problem that the related art does not consider using a film material with a fixed refractive index to reduce loss and enhance the reflection brightness.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is as follows: a high-brightness reflective sheet, comprising: a base film; a first adhesive layer, arranged on the surface of the base film corresponding to the light incident surface of the high-brightness reflective sheet; a silver-plated film, comprising a first substrate and a silver-plated layer arranged on the first substrate, wherein the first substrate is bonded to the first adhesive layer; a second adhesive layer, arranged on the silver-plated layer; a light-transmitting film, bonded to the second adhesive layer; wherein the thickness of the first adhesive layer is 3 to 5 μm, and the base film, the first adhesive layer and the silver-plated film are combined into a fixed stack film with a total thickness of 41 to 43 μm; the thickness of the second adhesive layer is 3 to 5 μm, and the refractive index of the second adhesive layer 400 is 1.482 to 1.523; the thickness of the light-transmitting film is 37 to 39 μm, and the haze value of the light-transmitting film 500 is not more than 1%, and the light transmittance of the light-transmitting film is greater than 88%.

[0006] In the above-mentioned high brightness reflector, by stacking a second adhesive layer of a single material with a specific refractive index on the silver-plated film, the reflected brightness gain of the light is adjusted, and the brightness of the reflector is enhanced on the basis of the existing reflector, which solves the problem that the related technical field does not consider using a film material with a fixed refractive index to reduce loss and enhance the reflected brightness, and achieves the beneficial effect of enhancing the brightness of the reflector. At the same time, by stacking the fixed base film, the first adhesive layer and the silver-plated film, the thickness of the fixed stacked film below the silver-plated film is fixed, and the loss of light in the fixed stacked film is fixed, so as to reduce the influence of the overall thickness of the reflector on improving the brightness of the reflector.

[0007] In some of the embodiments, in order to enhance the brightness gain of the high brightness reflective sheet, the second adhesive layer 400 is a UV light-cured pressure-sensitive adhesive layer.

[0008] In some embodiments, the thickness of the second glue layer is 5 μm, and the refractive index thereof is 1.510; or the thickness of the second glue layer is 3 μm, and the refractive index thereof is 1.513.

[0009] In some of the embodiments, in order to solidify the structure of the silver-plated film and fix the refractive efficiency of the fixed stack film, the silver-plated film also includes a first primer layer arranged between the first substrate and the silver-plated layer and a first protective layer arranged on the silver-plated layer, wherein the thickness of the silver-plated film is 26 μm, the first substrate includes a PET substrate layer, the first primer layer includes one of the following: a UV glue primer layer, a thermosetting resin primer layer, a polyester primer layer, a polyurethane primer layer, and / or the first protective layer includes one of the following: a polyester protective layer, a polyurethane protective layer.

[0010] In some embodiments, in order to achieve reflection of the silver-plated film, the silver-plated layer includes at least one of the following: a silver layer or a silver alloy layer, and the silver-plated layer is evaporated or sputtered on the first base coating layer.

[0011] In some embodiments, the first adhesive layer is a polyurethane resin adhesive layer.

[0012] In some embodiments, the light-transmitting film is a PET transparent film, and the thickness of the light-transmitting film is 38 μm.

[0013] In some of the embodiments, in order to achieve a fixed thickness of the stacked film below the fixed silver-plated film and a fixed refractive index of the stacked film, the thickness of the base film is 12 μm, and the base film includes one of the following: PET white film, PET black film, PET transparent film.

[0014] In some of the embodiments, in order to further achieve the fixed thickness of the stacked film below the fixed silver-plated film and the refractive index of the corresponding stacked film layer, the base film includes a second substrate, a second base coating layer provided on the second substrate, an aluminum layer evaporated or sputtered on the second base coating layer, and a second protective layer provided on the aluminum layer, wherein the thickness of the base film is 12 μm, the second substrate is a PET substrate, the second base coating layer includes one of the following: a UV glue base coating layer, a thermosetting resin base coating layer, a polyester base coating layer, a polyurethane base coating layer, and / or the second protective layer includes one of the following: a polyester protective layer, a polyurethane protective layer.

[0015] The present invention also provides a backlight module, comprising a back plate, a light source, a light guide plate and a high-brightness reflector sheet arranged in sequence, wherein the high-brightness reflector sheet is the high-brightness reflector sheet mentioned above. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A schematic diagram of the light traveling mode of an existing reflector;

[0017] Figure 2 is a structural schematic diagram of a high-brightness reflector according to an embodiment of the present invention;

[0018] Figure 3 Schematic diagram of the movement of a high brightness reflector according to an embodiment of the present invention

[0019] Figure 4 Schematic diagram of a high brightness reflector according to a preferred embodiment of the present invention Figure 1 ;

[0020] Figure 5 Schematic diagram of a high brightness reflector according to a preferred embodiment of the present invention Figure 2 .

[0021] Description of Reference Numerals

[0022] 100. Base film; 101. Second substrate; 102. Second base coating layer; 103. Aluminum layer; 104. Second protective layer;

[0023] 200. First gluing layer;

[0024] 300. Silver-plated film; 301. First substrate; 302. Silver-plated layer; 303. First primer layer; 304. First protective layer;

[0025] 400. First glue layer;

[0026] 500.Light-transmitting film. DETAILED DESCRIPTION

[0027] The present invention will be further described in detail below in conjunction with the accompanying drawings.

[0028] The embodiments described with reference to the accompanying drawings are exemplary and are intended to be used to explain the present application, and cannot be understood as limiting the present application. In the description of the present application, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise" and the like indicate the orientation or position relationship based on the orientation or position relationship shown in the accompanying drawings, which is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or component referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present application. In addition, the terms "first" and "second" are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present application, the meanings of "several" and "multiple" are two or more, unless otherwise clearly and specifically defined. In this application, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be a communication between two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances. In this application, unless otherwise clearly specified and limited, the first feature "above" or "below" the second feature can include the first and second features directly contacting, or it can include the first and second features not directly contacting but contacting through another feature between them. Moreover, the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply means that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly above and obliquely above the second feature, or simply means that the first feature is lower in level than the second feature.

[0029] Figure 2 1 is a schematic diagram of a structure of a reflector according to an embodiment of the present invention. The high brightness reflector shown in the figure adjusts the reflection brightness gain of light by stacking a second adhesive layer 200 of a specific refractive index and a single material on the silver-plated film 300, and fixes the thickness of the stacked film layer of the reflector below the silver-plated film and the loss on the stacked film layer, thereby reducing the influence of the loss of the stacked film layer on the brightness of the reflector.

[0030] Please see attached Figure 2A high brightness reflective sheet according to an embodiment of the present invention comprises: a base film 100; a first adhesive layer 200, disposed on the surface of the base film 100 corresponding to the light incident surface of the high brightness reflective sheet; a silver-plated film 300, comprising a first substrate 301 and a silver-plated layer 302 disposed on the first substrate 301, wherein the first substrate 301 is bonded to the first adhesive layer 200; a second adhesive layer 400, disposed on the silver-plated layer 302; a light-transmitting film 500, bonded to the second adhesive layer 400; wherein The thickness of the first adhesive layer 200 is 3 to 5 μm, and the base film 100, the first adhesive layer 200 and the silver-plated film 300 are combined into a fixed stack film with a total thickness of 41 to 43 μm; the thickness of the second adhesive layer 400 is 3 to 5 μm, and the refractive index of the second adhesive layer 400 is 1.482 to 1.523; the thickness of the light-transmitting film 500 is 37 to 39 μm, and the haze value of the light-transmitting film 500 is 0.8 to 1, and the transmittance of the light-transmitting film 500 is greater than 88%.

[0031] In the above-mentioned high brightness reflector, by stacking the second adhesive layer 400 of a specific refractive index and a single material on the silver-plated film 300, the reflected brightness gain of the light is adjusted, and the brightness of the reflector is enhanced on the basis of the existing reflector, which solves the problem that the related technical field does not consider using a film material with a fixed refractive index to reduce loss and enhance the reflected brightness, and achieves the beneficial effect of enhancing the brightness of the reflector. At the same time, by stacking the fixed base film 100, the first adhesive layer 200 and the silver-plated film 300, the thickness of the fixed stack film below the silver-plated film 300 is fixed, and the loss of light on the fixed stack film is fixed, so as to reduce the influence of the overall thickness of the reflector on improving the brightness of the reflector.

[0032] It should be noted that the reference Figure 3 When light reaches the silver-plated film 300, the high-brightness reflector of the embodiment of the present invention is reflected back, and the light wave shape and the moving direction of the light change at the same time, resulting in loss at point P. When the light is transmitted to the fixed stack film composed of the silver-plated film 300, the first adhesive layer 200 and the base film 100 below point P, the loss is fixed because the overall thickness of the silver-plated film 300, the first adhesive layer 200 and the base film 100 and the refractive index of the material are fixed, thereby achieving the fixation of the loss below point P, and the research object of improving the brightness gain only considers the brightness gain above point P.

[0033] In some of the embodiments, in order to enhance the brightness gain of the high brightness reflective sheet, the second adhesive layer 400 is a UV light-cured pressure-sensitive adhesive layer.

[0034] In this way, a single UV light-cured sub-sensitive adhesive layer is arranged on the high-brightness reflector, thereby solving the problem that the brightness gain adjustment of the reflector is difficult due to materials with different refractive indices.

[0035] In some embodiments, the thickness of the second glue layer 400 is 5 μm, and the refractive index thereof is 1.510; or, the thickness of the second glue layer 400 is 3 μm, and the refractive index thereof is 1.513.

[0036] The LB-8601 brightness box was used to measure the brightness (B) of the high brightness reflective sheet of the embodiment of the present invention with the second adhesive layer of different thickness (d) and different refractive index (n), as shown in the following table:

[0037]

[0038]

[0039] The high brightness reflector in the embodiment of the present invention with a size of 118x65mm is used to compare the brightness increase with a conventional reflector (the reflector is a reflector that has been commercially sold by the inventor of the present application). The test voltage of the test backlight module is 19V, the current is 0.04A, and the brightness increase = (brightness value - 8601) / 8601, as shown in the following table:

[0040]

[0041]

[0042] According to the above test data, in this embodiment, the thickness of the second adhesive layer 400 is set to 5 μm, and the refractive index n is selected to be 1.510, and the maximum brightness increase of the reflector luminance can be obtained. In other optional embodiments, the thickness of the second adhesive layer 400 is set to 3 μm, and the refractive index n is selected to be 1.513, and the maximum brightness increase of the reflector luminance can also be obtained.

[0043] In order to solidify the structure of the reflector and fix the refractive efficiency of the fixed stack film, refer to the attached Figure 4 In some embodiments, the silver-plated film 300 also includes a first primer layer 303 disposed between the first substrate 301 and the silver-plated layer 302 and a first protective layer 304 disposed on the silver-plated layer 302, wherein the thickness of the silver-plated film 300 is 26 μm, the first substrate 301 includes a PET substrate layer, the first primer layer 303 includes one of the following: a UV glue primer layer, a thermosetting resin primer layer, a polyester primer layer, a polyurethane primer layer, and / or the first protective layer includes one of the following: a polyester protective layer, a polyurethane protective layer.

[0044] In order to achieve reflection of the silver-plated film, in some embodiments, the silver-plated layer 302 includes at least one of the following: a silver reflection layer, a silver alloy reflection layer, and the silver-plated layer 302 is evaporated or sputtered on the first base coating layer 303 .

[0045] In some embodiments, the first adhesive layer 200 is a polyurethane resin adhesive layer.

[0046] In some embodiments, the light-transmitting film 500 is a PET transparent film, and the thickness of the light-transmitting film 500 is 38 μm.

[0047] In order to achieve a fixed silver film below 300, a fixed stack film thickness and a fixed stack film refractive index, refer to the attached Figure 2 and attached Figure 4 In some embodiments, the thickness of the base film 100 is 12 μm, and the base film 100 includes one of the following: PET white film, PET black film, and PET transparent film.

[0048] In order to further realize the fixed thickness of the stacked film below the silver-plated film 300 and the corresponding refractive index of the stacked film layer, refer to the attached Figure 5 In some embodiments, the base film 100 includes a second substrate 101, a second primer layer 102 disposed on the second substrate 101, an aluminum layer 103 evaporated or sputtered on the second primer layer 102, and a second protective layer 104 disposed on the aluminum layer 103, wherein the thickness of the base film 100 is 12 μm, the second substrate 101 is a PET substrate, the second primer layer 102 includes one of the following: a UV glue primer layer, a thermosetting resin primer layer, a polyester primer layer, a polyurethane primer layer, and / or the second protective layer 104 includes one of the following: a polyester protective layer, a polyurethane protective layer.

[0049] The present invention also provides an embodiment of a backlight module, which comprises a back plate, a light source, a conduit plate and a high-brightness reflector arranged in sequence. The high-brightness reflector is any one of the high-brightness reflectors in the above embodiments.

[0050] The above does not limit the technical scope of the present invention in any way. Any modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A high brightness reflective sheet, characterized in that: include: Base film (100); A first adhesive layer (200) is provided on the surface of the base film (100) corresponding to the light incident surface of the high brightness reflective sheet; A silver-plated film (300), comprising a first substrate (301) and a silver-plated layer (302) provided on the first substrate (301), wherein the first substrate (301) is adhered to the first adhesive layer (200); A second adhesive layer (400) is disposed on the silver-plated layer (302); A light-transmitting film (500) is attached to the second adhesive layer (400); wherein: The thickness of the first adhesive layer (200) is 3 to 5 μm, and the base film (100), the first adhesive layer (200) and the silver-plated film (300) are combined to form a fixed stacked film with a total thickness of 41 to 43 μm; the thickness of the second adhesive layer (400) is 3 to 5 μm, and the refractive index of the second adhesive layer (400) is 1.482 to 1.523; the thickness of the light-transmitting film (500) is 37 to 39 μm, and the haze value of the light-transmitting film (500) is not greater than 1.0%, and the light transmittance of the light-transmitting film (500) is greater than 88%; The thickness of the second glue layer (400) is 5 μm, and the refractive index thereof is 1.510, or the thickness of the second glue layer (400) is 3 μm, and the refractive index thereof is 1.

513. The silver-plated film (300) further comprises a first primer layer (303) disposed between the first substrate (301) and the silver-plated layer (302) and a first protective layer (304) disposed on the silver-plated layer (302), wherein the thickness of the silver-plated film (300) is 26 μm, the first substrate (301) comprises a PET substrate layer, the first primer layer (303) comprises one of the following: a UV glue primer layer, a thermosetting resin primer layer, a polyester primer layer, a polyurethane primer layer, and / or the first protective layer comprises one of the following: a polyester protective layer, a polyurethane protective layer.

2. The high brightness reflector according to claim 1, characterized in that: The second adhesive layer (400) is a UV light-cured pressure-sensitive adhesive layer.

3. The high brightness reflector according to claim 1, characterized in that: The silver-plated layer (302) comprises at least one of the following: a silver layer and a silver alloy layer, and the silver-plated layer (302) is evaporated or sputtered on the first base coating layer (303).

4. The high brightness reflector according to claim 1, characterized in that: The first adhesive layer (200) is a polyurethane resin adhesive layer.

5. The high brightness reflector according to claim 1, characterized in that: The light-transmitting film (500) is a PET transparent film, and the thickness of the light-transmitting film (500) is 38 μm.

6. The high brightness reflector according to claim 1, characterized in that: The thickness of the base film (100) is 12 μm, and the base film (100) comprises one of the following: a PET white film, a PET black film, or a PET transparent film.

7. The high brightness reflector according to claim 1, characterized in that: The base film (100) comprises a second substrate (101), a second primer layer (102) disposed on the second substrate (101), an aluminum layer (103) evaporated or sputtered on the second primer layer (102), and a second protective layer (104) disposed on the aluminum layer (103), wherein the base film (100) has a thickness of 12 μm, the second substrate (101) is a PET substrate, the second primer layer (102) comprises one of the following: a UV glue primer layer, a thermosetting resin primer layer, a polyester primer layer, a polyurethane primer layer, and / or the second protective layer (104) comprises one of the following: a polyester protective layer, a polyurethane protective layer.

8. A backlight module, comprising a back plate, a light source, a conduit plate, and a high-brightness reflector arranged in sequence, characterized in that: The high-brightness reflective sheet is the high-brightness reflective sheet according to any one of claims 1 to 7.

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