Optical structural plate and preparation method and application thereof

Abstract

The invention provides an optical structural plate and a preparation method and application thereof, and particularly relates to the technical field of backlight and illumination. The optical structural plate has a double-layer structure, and the double-layer structure comprises a lower substrate layer and an upper structural layer. The base material layer comprises polystyrene, a first compatilizer and a first additive. The structural layer comprises polypropylene, a second compatilizer and a second additive. According to the optical structural plate provided by the invention, polystyrene is used as a lower-layer base material, so that the optical structural plate has the advantages of low price and high light transmittance; meanwhile, polypropylene is used as a structural layer material, so that processing and forming are easy. In addition, the compatilizer is introduced into the upper layer and the lower layer, so that the interlayer bonding performance is improved, and the stability and the reliability of the double-layer structure are ensured. According to the optical structural plate, by means of scientific material selection and exquisite structural design, the follow-up production difficulty is remarkably reduced, and favorable conditions are created for large-scale industrial production.

Description

Technical Field

[0001] The present invention relates to the technical field of backlight and lighting, and particularly to an optical structure board, a preparation method thereof, and an application thereof. Background Art

[0002] In the prior art, a structure board of GPPS (GPPS is the English abbreviation for general polystyrene) is prepared by means of roll pressing, and an optical structure is prepared on the surface of the board. However, this method has some problems. On the one hand, it has certain requirements for the temperature of the board. The Tg of GPPS is usually 100°C. When the temperature of the board is too high, the strength of the GPPS board is insufficient, and it cannot be drawn and rolls are stuck; when the temperature of the board is too low, the GPPS board is not softened enough, and the structure cannot be pressed. On the other hand, due to continuous production, the structure is only formed on the contact surface of the two rolls, and the contact time is very short, so there are also certain requirements for the pressure between the pressing rolls.

[0003] In order to overcome these problems, the prior art mainly increases hydraulic equipment at the equipment end to increase the pressure to force the preparation of the structure. However, this method not only greatly increases the equipment cost, but also increases the difficulty of process operation. At the same time, the pressed structure cannot ensure integrity, and the structure replication rate is low.

[0004] In view of this, the present invention is specifically proposed. Summary of the Invention

[0005] One of the purposes of the present invention is to provide an optical structure board, aiming to solve at least one of the above technical problems in the prior art.

[0006] Another purpose of the present invention is to provide a preparation method of an optical structure board.

[0007] The third purpose of the present invention is to provide an application of an optical structure board.

[0008] In order to achieve the above purposes of the present invention, the following technical solutions are specifically adopted:

[0009] The first aspect of the present invention provides an optical structure board with a double-layer structure, and the double-layer structure includes a substrate layer in the lower layer and a structure layer in the upper layer.

[0010] The substrate layer includes polystyrene, a first compatibilizer, and a first additive.

[0011] The structure layer includes polypropylene, a second compatibilizer, and a second additive.

[0012] Further, the surface of the structure layer has a prism structure.

[0013] Preferably, the pitch of the prism structure is 49.0 - 52.5 μm, and the height is 23.0 - 26.0 μm.

[0014] Preferably, the thickness of the base material layer is 0.7 - 1.95 mm.

[0015] Preferably, the thickness of the structure layer is 0.075 - 0.125 mm.

[0016] Further, by weight parts, the base material layer includes 98 parts of polystyrene, 0.8 - 1.2 parts of a first compatibilizer, and 0.8 - 1.2 parts of a first additive.

[0017] Preferably, by weight parts, the structure layer includes 88 - 98 parts of polypropylene, 0.8 - 1.2 parts of a second compatibilizer, 0.8 - 1.2 parts of a second additive, and optionally 8 - 12 parts of a low - melting - point polymer.

[0018] Further, the melting point of the low - melting - point polymer is ≤160 °C.

[0019] Preferably, the low - melting - point polymer includes SEBS or POE.

[0020] Further, the first compatibilizer is maleic anhydride - grafted polystyrene.

[0021] Preferably, the grafting rate of the maleic anhydride - grafted polystyrene is 1.0 - 2.0%.

[0022] Preferably, the second compatibilizer is maleic anhydride - grafted polypropylene.

[0023] Preferably, the grafting rate of the maleic anhydride - grafted polypropylene is 1.0 - 2.0%.

[0024] Further, by weight parts, each of the first additive and the second additive independently includes 0.2 - 0.5 parts of an antioxidant, 0.2 - 0.5 parts of an ultraviolet absorber, and 0.1 - 0.3 parts of a flow aid.

[0025] Preferably, the grades of the antioxidant include antioxidant 1010, antioxidant 168, and antioxidant 1076.

[0026] Preferably, the grades of the ultraviolet absorber include ultraviolet absorber UV - P, ultraviolet absorber UV - 770, and ultraviolet absorber UV - 531.

[0027] Preferably, the flow aid includes zinc stearate, calcium stearate, and magnesium stearate.

[0028] In the second aspect of the present invention, a method for preparing the optical structure board is provided. After mixing the raw materials of the substrate layer and the raw materials of the structure layer, they are respectively fed into the first extruder and the second extruder through independent feeding ports, and are independently extruded into the gap between the No. 1 roller and the No. 2 roller. After being co-compressed, they enter the No. 3 cooling roller for cooling and shaping to obtain the optical structure board.

[0029] Among them, the surface of the No. 2 roller has a prism structure.

[0030] The pitch of the prism structure is 49.0 - 52.5 μm, and the height is 23.0 - 26.0 μm.

[0031] Furthermore, the substrate layer is attached to the roller surface of the No. 1 roller, and the structure layer is attached to the roller surface of the No. 2 roller.

[0032] Preferably, the extrusion temperature of the first extruder is 210 - 230 °C, and the feeding speed is 160 - 200 kg / h.

[0033] Preferably, the extrusion temperature of the second extruder is 160 - 200 °C, and the feeding speed is 15 - 25 kg / h.

[0034] Preferably, the roller surface temperature of the No. 1 roller and the No. 2 roller is 110 - 125 °C.

[0035] Preferably, the roller surface temperature of the No. 3 cooling roller is 80 - 100 °C.

[0036] Furthermore, the thickness of the substrate layer extruded by the first extruder is 0.7 - 1.95 mm.

[0037] Preferably, the thickness of the structure layer extruded by the second extruder is 0.05 - 0.1 mm.

[0038] In the third aspect of the present invention, an application of the optical structure board in preparing a display or a lighting device is provided.

[0039] Compared with the prior art, the present invention has at least the following beneficial effects:

[0040] The optical structure board provided by the present invention uses polystyrene as the lower substrate, which has the advantages of low price and high light transmittance; at the same time, polypropylene is used as the material of the structure layer, which is easy to process and form. In addition, a compatibilizer is introduced into the upper and lower layers to improve the interfacial adhesion performance, ensuring the stability and reliability of the double-layer structure. With scientific material selection and delicate structure design, the optical structure board significantly reduces the difficulty of subsequent production, creating favorable conditions for large-scale industrial production.

[0041] The preparation method of the optical structure plate provided by the present invention has higher process stability, better structure replication rate, and the light enhancement effect reaches 29-32%. At the same time, due to the lower requirements for equipment, it is easy to achieve mass production, reducing the production cost and the difficulty of process operation.

[0042] The application of the optical structure plate provided by the present invention, in view of the advantages of the above optical structure plate, can significantly improve the optical performance and structural stability of the display or lighting device, and at the same time has good process adaptability and cost-effectiveness, providing advanced technical support and solutions for the manufacture of display and lighting devices. Brief Description of the Drawings

[0043] In order to more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the following will briefly introduce the drawings required for the description of the specific embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0044] Figure 1 Among them, (a) is the 3D morphology diagram of the optical structure plate sample obtained in Example 1, Figure 1 Among them, (b) is the morphology diagram of the optical structure plate sample obtained in Example 1, Figure 1 Among them, (c) is the contour diagram of the optical structure plate sample obtained in Example 1;

[0045] Figure 2 Among them, (a) is the 3D morphology diagram of the optical structure plate obtained in Example 2, Figure 2 Among them, (b) is the morphology diagram of the optical structure plate sample obtained in Example 2, Figure 2 Among them, (c) is the contour diagram of the optical structure plate sample obtained in Example 2;

[0046] Figure 3 Among them, (a) is the 3D morphology diagram of the optical structure plate obtained in Example 3, Figure 3 Among them, (b) is the morphology diagram of the optical structure plate sample obtained in Example 3, Figure 3 Among them, (c) is the contour diagram of the optical structure plate sample obtained in Example 3;

[0047] Figure 4 Among them, (a) is the 3D morphology diagram of the optical structure plate obtained in Comparative Example 1, Figure 4 Among them, (b) is the morphology diagram of the optical structure plate sample obtained in Comparative Example 1, Figure 4 Among them, (c) is the contour diagram of the optical structure plate sample obtained in Comparative Example 1. Detailed Embodiments

[0048] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Apparently, the described embodiments are only a part rather than all of the embodiments of the present invention.

[0049] In the following text, the terms "comprising", "having" and their cognates that can be used in various embodiments of the present invention are only intended to represent specific features, numbers, steps, operations, elements, components or combinations of the foregoing items, and should not be construed as precluding the existence or adding the possibility of one or more other features, numbers, steps, operations, elements, components or combinations of the foregoing items first.

[0050] The first aspect of the present invention provides an optical structural plate having a double-layer structure, and the double-layer structure includes a substrate layer in the lower layer and a structural layer in the upper layer.

[0051] The substrate layer includes polystyrene, a first compatibilizer and a first additive.

[0052] The structural layer includes polypropylene, a second compatibilizer and a second additive.

[0053] The optical structural plate provided by the present invention uses polystyrene as the lower substrate, which has the advantages of low price and high light transmittance; at the same time, polypropylene is used as the structural layer material, which is easy to process and form. In addition, compatibilizers are introduced into the upper and lower layers to improve the interlayer bonding performance and ensure the stability and reliability of the double-layer structure. With scientific material selection and delicate structural design, the optical structural plate significantly reduces the difficulty of subsequent production and creates favorable conditions for large-scale industrial production.

[0054] Further, the surface of the structural layer has a prism structure.

[0055] Preferably, the pitch of the prism structure is 49.0 - 52.5 μm and the height is 23.0 - 26.0 μm.

[0056] Typically but not restrictively, the pitch of the prism structure can be, for example, 49.0 μm, 49.5 μm, 50.0 μm, 50.5 μm, 51.0 μm or 52.5 μm, or any value within the range of 49.0 - 52.5 μm; the height of the prism structure can be, for example, 23.0 μm, 23.25 μm, 23.5 μm, 23.75 μm, 24.5 μm or 26.0 μm, or any value within the range of 23.0 - 26.0 μm.

[0057] In the specific implementation process, the pitch and height of the prism structure are adjusted according to the requirements of the optical structural plate.

[0058] The pitch refers to the distance between the central points of adjacent peaks and valleys of the prism structure.

[0059] Preferably, the thickness of the base material layer is 0.7 - 1.95 mm.

[0060] Typical but non - limiting, the thickness of the base material layer can be, for example, 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm, 1.9 mm or 1.95 mm, or any value within the range of 0.7 - 1.95 mm.

[0061] Preferably, the thickness of the structure layer is 0.075 - 0.125 mm.

[0062] Typical but non - limiting, the thickness of the structure layer can be, for example, 0.075 mm, 0.085 mm, 0.095 mm, 0.105 mm, 0.115 mm or 0.125 mm, or any value within the range of 0.075 - 0.125 mm.

[0063] Further, by weight parts, the base material layer includes 98 parts of polystyrene, 0.8 - 1.2 parts of a first compatibilizer, and 0.8 - 1.2 parts of a first additive.

[0064] Typical but non - limiting, the weight parts of each component in the base material layer can be as follows: polystyrene is 98 parts, the first compatibilizer can be 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts or 1.2 parts, or any value within the range of 0.8 - 1.2 parts; the first additive can be 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts or 1.2 parts, or any value within the range of 0.8 - 1.2 parts.

[0065] Preferably, by weight parts, the structure layer includes 88 - 98 parts of polypropylene, 0.8 - 1.2 parts of a second compatibilizer, 0.8 - 1.2 parts of a second additive, and optionally 8 - 12 parts of a low - melting - point polymer.

[0066] Typical but non - limiting, the weight parts of each component in the structure layer can be as follows: polypropylene can be 88 parts, 90 parts, 92 parts, 94 parts, 96 parts or 98 parts, or any value within the range of 88 - 98 parts; the second compatibilizer can be 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts or 1.2 parts, or any value within the range of 0.8 - 1.2 parts; the second additive can be 0.8 parts, 0.9 parts, 1.0 parts, 1.1 parts or 1.2 parts, or any value within the range of 0.8 - 1.2 parts; the low - melting - point polymer (if added) can be 8 parts, 9 parts, 10 parts, 11 parts or 12 parts, or any value within the range of 8 - 12 parts.

[0067] Further, the melting point of the low-melting polymer is ≤ 160 °C.

[0068] Preferably, the low-melting polymer includes SEBS or POE.

[0069] Further, the first compatibilizer is maleic anhydride grafted polystyrene.

[0070] Preferably, the grafting rate of the maleic anhydride grafted polystyrene is 1.0 - 2.0%.

[0071] Typical but non-limiting, the grafting rate of the maleic anhydride grafted polystyrene can be 1.0%, 1.2%, 1.4%, 1.6%, 1.8% or 2.0%, or any value within the range of 1.0% - 2.0%.

[0072] Preferably, the second compatibilizer is maleic anhydride grafted polypropylene.

[0073] Preferably, the grafting rate of the maleic anhydride grafted polypropylene is 1.0 - 2.0%.

[0074] Typical but non-limiting, the grafting rate of the maleic anhydride grafted polypropylene can be 1.0%, 1.2%, 1.4%, 1.6%, 1.8% or 2.0%, or any value within the range of 1.0% - 2.0%.

[0075] Further, by weight parts, each of the first additive and the second additive independently includes 0.2 - 0.5 parts of antioxidant, 0.2 - 0.5 parts of ultraviolet absorber, and 0.1 - 0.3 parts of flow aid.

[0076] Typical but non-limiting, each of the first additive and the second additive independently includes: the antioxidant can be 0.2 parts, 0.3 parts, 0.4 parts or 0.5 parts, or any value within the range of 0.2 - 0.5 parts; the ultraviolet absorber can be 0.2 parts, 0.3 parts, 0.4 parts or 0.5 parts, or any value within the range of 0.2 - 0.5 parts; the flow aid can be 0.1 parts, 0.2 parts or 0.3 parts, or any value within the range of 0.1 - 0.3 parts.

[0077] "Independently" means that the formulation of the first additive can be the same as or different from that of the second additive, and there is no relationship between the material selection and value taking of the two.

[0078] Preferably, the grades of the antioxidant include antioxidant 1010, antioxidant 168, antioxidant 1076.

[0079] Preferably, the grades of the ultraviolet light absorber include ultraviolet light absorber UV-P, ultraviolet light absorber UV-770, and ultraviolet light absorber UV-531.

[0080] Preferably, the flow aids include zinc stearate, calcium stearate, and magnesium stearate.

[0081] In the second aspect of the present invention, there is provided a method for preparing the optical structure plate. The raw materials of the substrate layer and the raw materials of the structure layer are mixed and then respectively fed into a first extruder and a second extruder through independent feeding ports, and are independently extruded into the gap between a No. 1 roller and a No. 2 roller, and after being cooperatively pressed, they enter a No. 3 cooling roller for cooling and shaping to obtain the optical structure plate.

[0082] No. 1 roller (upper roller): The smooth roller presses downward to press the plate towards the No. 2 roller; No. 2 roller (lower roller): The prism protrusions on the surface of the structure roller are embedded in the upper PP melt to form a micro-structure. The plate with the micro-structure leaves the No. 2 roller and enters the gap between the No. 2 roller and the No. 3 cooling roller; No. 3 cooling roller: The 90°C smooth roller contacts the back surface of the plate (the lower layer PS substrate side), and the upper PP micro-structure is solidified and shaped by cooling; the prism structure changes from the molten state to the solid state, and the surface is smooth without rebound.

[0083] Among them, the surface of the No. 2 roller has a prism structure, and an optical micro-structure is imprinted through the surface prism structure.

[0084] The pitch of the prism structure is 49.0 - 52.5 μm, and the height is 23.0 - 26.0 μm.

[0085] Typical but non-limiting, the pitch of the prism structure can be, for example, 49.0 μm, 49.5 μm, 50.0 μm, 50.5 μm, 51.0 μm, or 52.5 μm, or any value within the range of 49.0 - 52.5 μm; the height of the prism structure can be, for example, 23.0 μm, 23.25 μm, 23.5 μm, 23.75 μm, 24.5 μm, or 26.0 μm, or any value within the range of 23.0 - 26.0 μm.

[0086] The method for preparing the optical structure plate provided by the present invention has higher process stability, better structure replication rate, and the light enhancement effect reaches 29 - 32%. At the same time, due to the lower requirements for equipment, it is easy to achieve mass production, reducing the production cost and the difficulty of process operation.

[0087] Furthermore, the substrate layer is attached to the roller surface of the No. 1 roller, and the structure layer is attached to the roller surface of the No. 2 roller.

[0088] Preferably, the extrusion temperature of the first extruder is 210 - 230 °C, and the feeding speed is 160 - 200 kg / h.

[0089] Typically but not restrictively, the extrusion temperature of the first extruder can be 210°C, 215°C, 220°C, 225°C or 230°C, or any value within the range of 210°C to 230°C. The feeding speed can be 160 kg / h, 170 kg / h, 180 kg / h, 190 kg / h or 200 kg / h, or any value within the range of 160 kg / h to 200 kg / h.

[0090] Preferably, the extrusion temperature of the second extruder is 160 - 200°C, and the feeding speed is 15 - 25 kg / h.

[0091] Typically but not restrictively, the extrusion temperature of the second extruder can be 160°C, 170°C, 180°C, 190°C or 200°C, or any value within the range of 160°C to 200°C; the feeding speed can be 15 kg / h, 17.5 kg / h, 20 kg / h, 22.5 kg / h or 25 kg / h, or any value within the range of 15 kg / h to 25 kg / h.

[0092] Preferably, the surface temperature of the No. 1 roller and the No. 2 roller is 110 - 125°C.

[0093] Typically but not restrictively, the surface temperature of the No. 1 roller and the No. 2 roller can be 110°C, 115°C, 120°C, 125°C, or any value within the range of 110°C to 125°C.

[0094] Preferably, the surface temperature of the No. 3 cooling roller is 80 - 100°C. Typically but not restrictively, the surface temperature of the No. 3 cooling roller can be 80°C, 85°C, 90°C, 95°C or 100°C, or any value within the range of 80°C to 100°C.

[0095] Furthermore, the thickness of the base material layer extruded by the first extruder is 0.7 - 1.95 mm. Typically but not restrictively, the thickness of the base material layer extruded by the first extruder can be 0.7 mm, 0.9 mm, 1.1 mm, 1.3 mm, 1.5 mm, 1.7 mm or 1.95 mm, or any value within the range of 0.7 mm to 1.95 mm.

[0096] Preferably, the thickness of the structural layer extruded by the second extruder is 0.05 - 0.1 mm.

[0097] Typically but not restrictively, the thickness of the structural layer extruded by the second extruder can be 0.05 mm, 0.06 mm, 0.07 mm, 0.08 mm, 0.09 mm or 0.1 mm, or any value within the range of 0.05 mm to 0.1 mm.

[0098] The third aspect of the present invention provides an application of the optical structure board in the preparation of a display or a lighting device.

[0099] Regarding the application of the optical structure board provided by the present invention, in view of the advantages of the above optical structure board, it can significantly improve the optical performance and structural stability of a display or a lighting device, and at the same time has good process adaptability and cost-effectiveness, providing advanced technical support and solutions for the manufacture of displays and lighting devices. The present invention will be further described below through specific examples and comparative examples. However, it should be understood that these examples are only for more detailed description and should not be construed as limiting the present invention in any form. For the raw materials used in the examples and comparative examples of the present invention, unless otherwise specified, they are carried out under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used without indicating the manufacturer are all conventional products that can be obtained through commercial purchase.

[0100] Example 1

[0101] This example provides an optical structure board, and the preparation method is as follows:

[0102] 1. By mass, put polystyrene substrate (PS133N - Tianjin Rantai, 98 parts), antioxidant (antioxidant 1010 is 0.3 parts, antioxidant 168 is 0.1 part), ultraviolet absorber (ultraviolet absorber UV-P is 0.3 parts, ultraviolet absorber UV-770 is 0.1 part), flow aid (zinc stearate 0.2 parts) and compatibilizer (PS-MAH is 1 part, and its grafting rate is 1.5%) into a blender, mix evenly, and then put it into the No. 1 feeding port for preparing the lower substrate.

[0103] 2. By mass, put polypropylene substrate (FL7632L - Singapore Polyolefins, 98 parts), antioxidant (antioxidant 1010 is 0.3 parts, antioxidant 168 is 0.1 part), ultraviolet absorber (ultraviolet absorber UV-P is 0.3 parts, ultraviolet absorber UV-770 is 0.1 part), flow aid (zinc stearate is 0.2 parts) and compatibilizer (PP-MAH is 1 part, and its grafting rate is 1.5%) into a blender, mix evenly, and then put it into the No. 2 feeding port for preparing the upper structure layer.

[0104] 3. Then use 2 single-screw extruders to extrude and form a board. Among them, the extrusion temperature of the No. 1 single-screw extruder is 220 °C, and the feeding speed is 180 Kg / h, which is used to extrude the lower substrate. The extrusion temperature of the No. 2 single-screw extruder is 180 °C, and the feeding speed is 20 Kg / h, which is used to extrude the upper structure layer. The total thickness of the board is controlled to be 1.0 mm.

[0105] 4. The sheet is pulled by 3 metal rollers, starting from between the 1st roller and the 2nd roller, and is pressed by the 1st roller and the 2nd roller to obtain the structure. Among them, the 1st roller is a smooth roller with a temperature set at 120 °C; the 2nd roller is a structured roller with a prism structure of pitch 50 μm and structure height 25 μm, and the temperature is set at 120 °C; the 3rd cooling roller is a smooth roller with a temperature set at 90 °C, obtaining the optical structure sheet.

[0106] Example 2

[0107] This example provides an optical structure sheet, and the preparation method is as follows:

[0108] 1. The same step as in Example 1.

[0109] 2. By mass fraction, put polypropylene base material (FL7632L - 88 parts of Singapore polyolefin), low - melting polymer (SEBS, 10 parts), antioxidant (0.3 parts of antioxidant 1010 and 0.1 part of antioxidant 168), ultraviolet absorber (0.3 parts of ultraviolet absorber UV - P and 0.1 part of ultraviolet absorber UV - 770), flow aid (0.2 parts of zinc stearate) and compatibilizer (1 part of PP - MAH with a grafting rate of 1.5%) into a blender, mix evenly and then put into the 2nd feeding port for preparing the upper structure layer.

[0110] 3. The same step as in Example 1.

[0111] 4. The same step as in Example 1.

[0112] Example 3

[0113] This example provides an optical structure sheet, and the preparation method is as follows:

[0114] 1. The same step as in Example 1.

[0115] 2. By mass fraction, put polypropylene base material (88 parts of FL7632L - Singapore polyolefin), low - melting polymer (POE, 10 parts), antioxidant (0.3 parts of antioxidant 1010 and 0.1 part of antioxidant 168), ultraviolet absorber (0.3 parts of ultraviolet absorber UV - P and 0.1 part of ultraviolet absorber UV - 770), flow aid (0.2 parts of zinc stearate) and compatibilizer (1 part of PP - MAH with a grafting rate of 1.5%) into a blender, mix evenly and then put into the 2nd feeding port for preparing the upper structure layer.

[0116] 3. The same step as in Example 1.

[0117] 4. The same step as in Example 1.

[0118] Example 4

[0119] This embodiment provides an optical structure board, and the preparation method is as follows:

[0120] 1. By mass, mix polystyrene substrate (PS133N - Tianjin Rantai, 98 parts), antioxidant (antioxidant 1076, 0.3 parts; antioxidant 168, 0.1 part), ultraviolet absorber (ultraviolet absorber UV - 531, 0.4 parts), flow aid (calcium stearate, 0.15 parts), and compatibilizer (PS - MAH, 1.2 parts, grafting rate 2.0%) evenly, and then put them into the No. 1 feeding port for preparing the lower substrate.

[0121] 2. By mass, mix polypropylene substrate (FL7632L - Singapore Polyolefins, 92 parts), low - melting polymer (POE, 8 parts), antioxidant (antioxidant 1076, 0.3 parts; antioxidant 168, 0.1 part), ultraviolet absorber (ultraviolet absorber UV - 531, 0.4 parts), flow aid (calcium stearate, 0.15 parts), and compatibilizer (PP - MAH, 1.2 parts, grafting rate 2.0%) evenly, and then put them into the No. 2 feeding port for preparing the upper structure layer.

[0122] 3. Use a twin - screw extruder to extrude and form the board. The extrusion temperature of the No. 1 extruder is 215°C, and the feeding speed is 170 kg / h; the extrusion temperature of the No. 2 extruder is 190°C, and the feeding speed is 18 kg / h. The total thickness of the board is 1.2 mm.

[0123] 4. Press through the No. 1 smooth roll (temperature 125°C) and the No. 2 structured roll (prism pitch 50 μm, height 25 μm, temperature 125°C), and then shape it through the No. 3 cooling roll (temperature 85°C) to obtain the optical structure board.

[0124] Example 5

[0125] This embodiment provides an optical structure board, and the preparation method is as follows:

[0126] 1. The same as this step in Example 1.

[0127] 2. The same as this step in Example 1.

[0128] 3. Then use 2 single - screw extruders to extrude and form the board. Among them, the extrusion temperature of the No. 1 single - screw extruder is 210°C, and the feeding speed is 180 Kg / h, which is used to extrude the lower substrate. The extrusion temperature of the No. 2 single - screw extruder is 200°C, and the feeding speed is 20 Kg / h, which is used to extrude the upper structure layer. The total thickness of the board is controlled to be 1.0 mm.

[0129] 4. The sheet is pulled by 3 metal rollers, starting from between the 1st roller and the 2nd roller, and is pressed by the 1st roller and the 2nd roller to obtain the structure. Among them, the 1st roller is a smooth roller with a temperature set at 125 °C; the 2nd roller is a structured roller with a prism structure of pitch 50 μm and structure height 25 μm, and the temperature is set at 125 °C; the 3rd cooling roller is a smooth roller with a temperature set at 80 °C, and the optical structured sheet is obtained.

[0130] Example 6

[0131] This example provides an optical structured sheet, and the preparation method is as follows:

[0132] 1. The same step as in Example 1.

[0133] 2. The same step as in Example 1.

[0134] 3. Then, use 2 single-screw extruders to extrude and form the sheet. Among them, the extrusion temperature of the 1st single-screw extruder is 230 °C, and the feeding speed is 180 Kg / h, which is used to extrude the lower substrate. The extrusion temperature of the 2nd single-screw extruder is 160 °C, and the feeding speed is 20 Kg / h, which is used to extrude the upper structure layer, and the total thickness of the sheet is controlled to be 1.0 mm.

[0135] 4. The sheet is pulled by 3 metal rollers, starting from between the 1st roller and the 2nd roller, and is pressed by the 1st roller and the 2nd roller to obtain the structure. Among them, the 1st roller is a smooth roller with a temperature set at 110 °C; the 2nd roller is a structured roller with a prism structure of pitch 50 μm and structure height 25 μm, and the temperature is set at 110 °C; the 3rd cooling roller is a smooth roller with a temperature set at 100 °C, and the optical structured sheet is obtained.

[0136] Comparative Example 1

[0137] This comparative example provides an optical structured sheet, and the preparation process is as follows:

[0138] 1. The same step as in Example 1.

[0139] 2. Then, use a single-screw extruder to extrude and form the sheet. Among them, the extrusion temperature of the single-screw extruder is 220 °C, and the feeding speed is 200 Kg / h, which is used to extrude the substrate, and the total thickness of the sheet is controlled to be 1.0 mm.

[0140] 3. The same as step 4 in Example 1.

[0141] Comparative Example 2

[0142] This comparative example provides an optical structured sheet, and the preparation process is as follows:

[0143] 1. The same step as in Example 1.

[0144] 2. Then, use a single-screw extruder to extrude and form the board. Among them, the extrusion temperature of the single-screw extruder is 220 °C, the feeding speed is 200 kg / h, which is used to extrude the substrate, and the total thickness of the board is controlled to be 1.0 mm.

[0145] 3. The board is tractioned through 3 metal rollers. The traction starts from the middle of roller No. 1 and roller No. 2. Among them, roller No. 1 is a smooth roller with a temperature set at 130 °C; roller No. 2 is a structured roller, and the structure of the structured roller is a prism structure with a pitch of 50 μm and a structure height of 25 μm, and the temperature is set at 130 °C; roller No. 3 cooling roller is a smooth roller with a temperature set at 90 °C. And the structure is pressed by roller No. 1 and roller No. 2, but there is a phenomenon of roll sticking, and the board cannot be prepared.

[0146] Comparative Example 3

[0147] This comparative example provides an optical structure board. Different from Example 1, in step 1, the compatibilizer (1 part of PS-MAH with a grafting rate of 1.5%) is not added; in step 2, the compatibilizer (1 part of PP-MAH with a grafting rate of 1.5%) is not added, and the remaining raw materials and preparation methods are the same as those in Example 1, which will not be elaborated here. However, due to the non-addition of the compatibilizer, the bonding between the boards is not good, and there is a delamination phenomenon in the board.

[0148] Characterization Example

[0149] Use the Keyence VK-X1000 / 1100 microscope to perform a structure scanning test on the optical structure boards obtained in Examples 1-3 and Comparative Example 1 to obtain the 3D sample morphology map (corresponding to a as shown in Figure 1 , a as shown in Figure 2 , a as shown in Figure 3 , a as shown in Figure 4 ) and the sample morphology map (corresponding to b as shown in Figure 1 , b as shown in Figure 2 , b as shown in Figure 3 , b as shown in Figure 4 ); and use the VK-X Series analysis software for profile analysis, respectively corresponding to select a suitable cross-section in Figure 1 , Figure 2 , Figure 3 , Figure 4 to obtain the sample profile map (corresponding to c as shown in Figure 1 , c as shown in Figure 2 , c as shown in Figure 3 , c as shown in Figure 4As shown by c in [reference], horizontal distance measurement and height difference measurement are carried out according to the contour map, and then the average values are calculated respectively to obtain the structural pitch value and structural height of the optical structure board. The closer the pitch of the board structure and the structural height are to the pitch (50 μm) and structural height (25 μm) of the roller structure, the higher the structural replication rate and the greater the luminance gain.

[0150] Test example

[0151] The pitch value, structural height and luminance gain of the surface structure of the optical structure boards obtained in the examples and comparative examples were tested.

[0152] By carrying out horizontal distance measurement and height difference measurement on the sample contour map, and then calculating the average values respectively, the pitch value and structural height of the surface structure of the optical structure board are obtained.

[0153] Luminance gain test method:

[0154] A 32-inch white light source is used, and its original structure is a white light source + a 32-inch diffusion plate. The luminance 1 is measured using a luminance meter CA-410. Then, the optical sheet prepared by extrusion is cut to 32 inches and placed above the 32-inch diffusion plate. At this time, the structure is a white light source + a 32-inch diffusion plate + a 32-inch optical structure board, and the luminance 2 is measured using a luminance meter. Luminance gain % = (luminance 2 / luminance 1) - 100%;

[0155] The results obtained are shown in Table 1 below.

[0156] Table 1

[0157]

[0158] As can be seen from Table 1, for the optical structure board provided by the present invention, by using polystyrene as the lower substrate and polypropylene as the structural layer material, it is easy to process and form. The structural replication rate is better, the structural height is closer to the theoretical value, and the luminance gain is significantly improved compared with the single-layer structure, reaching 29 - 32%.

[0159] Finally, it should be noted that the above-described embodiments are only specific embodiments of the present invention, used to illustrate the technical solutions of the present invention, rather than limiting it. The protection scope of the present invention is not limited thereto. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that any person skilled in the art within the technical scope disclosed by the present invention can still modify the technical solutions recorded in the foregoing embodiments or can easily think of changes, or perform equivalent replacements on some of the technical features; and these modifications, changes or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present invention, and should all be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims described.

Claims

1. An optical structural plate, characterized in that: It has a double-layer structure, which includes a lower substrate layer and an upper structural layer; The substrate layer includes polystyrene, a first compatibilizer and a first additive; The structural layer comprises polypropylene, a second compatibilizer and a second additive.

2. The optical structure plate according to claim 1, characterized in that: The surface of the structural layer has a prism structure; Preferably, the pitch of the prism structure is 49.0 to 52.5 μm, and the height is 23.0 to 26.0 μm; Preferably, the thickness of the substrate layer is 0.7 to 1.95 mm; Preferably, the thickness of the structural layer is 0.075-0.125 mm.

3. The optical structure plate according to claim 1, characterized in that: In terms of weight, the substrate layer includes 98 parts of polystyrene, 0.8 to 1.2 parts of a first compatibilizer, and 0.8 to 1.2 parts of a first additive; Preferably, in parts by weight, the structural layer comprises 88 to 98 parts of polypropylene, 0.8 to 1.2 parts of a second compatibilizer, 0.8 to 1.2 parts of a second additive and 8 to 12 parts of an optional low melting point polymer.

4. The optical structure plate according to claim 3, characterized in that: The melting point of the low melting point polymer is ≤160°C; Preferably, the low melting point polymer includes SEBS or POE.

5. The optical structural plate according to any one of claims 1 to 4, characterized in that: The first compatibilizer is maleic anhydride grafted polystyrene; Preferably, the grafting rate of the maleic anhydride grafted polystyrene is 1.0-2.0%; Preferably, the second compatibilizer is maleic anhydride grafted polypropylene; Preferably, the grafting rate of the maleic anhydride grafted polypropylene is 1.0-2.0%.

6. The optical structural plate according to any one of claims 1 to 4, characterized in that: In terms of weight, the first additive and the second additive each independently include 0.2 to 0.5 parts of an antioxidant, 0.2 to 0.5 parts of an anti-ultraviolet agent, and 0.1 to 0.3 parts of a flow aid; Preferably, the brands of the antioxidant include antioxidant 1010, antioxidant 168, and antioxidant 1076; Preferably, the brands of the anti-ultraviolet agent include anti-ultraviolet agent UV-P, anti-ultraviolet agent UV-770, and anti-ultraviolet agent UV-531; Preferably, the flow aid comprises zinc stearate, calcium stearate, and magnesium stearate.

7. A method for preparing an optical structure plate according to any one of claims 1 to 6, characterized in that: The raw materials of the substrate layer and the raw materials of the structural layer are mixed and fed into the first extruder and the second extruder respectively through independent feeding ports, and are independently extruded into the gap between roller No. 1 and roller No. 2, and after coordinated pressing, they enter the No. 3 cooling roller for cooling and shaping to obtain the optical structural plate.

8. The preparation method according to claim 7, characterized in that: The base material layer is laminated to the roller surface of the No. 1 roller, and the structural layer is laminated to the roller surface of the No. 2 roller; Preferably, the extrusion temperature of the first extruder is 210-230°C, and the feeding rate is 160-200kg / h; Preferably, the extrusion temperature of the second extruder is 160-200°C, and the feeding rate is 15-25kg / h; Preferably, the roller surface temperature of the No. 1 roller and the No. 2 roller is 110-125° C.; Preferably, the roller surface temperature of the No. 3 cooling roller is 80-100°C.

9. The preparation method according to claim 7, characterized in that: The surface of the No. 2 roller has a prism structure; Preferably, the pitch of the prism structure is 49.0 to 52.5 μm, and the height is 23.0 to 26.0 μm; Preferably, the thickness of the substrate layer extruded by the first extruder is 0.7 to 1.95 mm; Preferably, the thickness of the structural layer extruded by the second extruder is 0.05-0.1 mm.

10. Use of the optical structural plate according to any one of claims 1 to 6 in preparing a display or a lighting device.

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