High-strength light diffusion backboard and preparation method thereof

Abstract

The invention relates to the technical field of light diffusion plates, in particular to a high-strength light diffusion backboard and a preparation method thereof. The MS brittleness is high, and the flexibility, the heat resistance and the dimensional stability are poor when the MS is used as a light diffusion back plate. In order to solve the technical problems, the invention provides the high-strength light diffusion backboard, the MS is used as a resin matrix, the chopped glass fiber is used as a reinforcing agent, and the chopped glass fiber is added into the resin matrix in a side feeding manner, so that the obtained high-strength light diffusion backboard has excellent toughness, heat resistance and dimensional stability; good market application prospects are realized.

Description

Technical Field

[0001] The invention relates to the technical field of light diffusion plates, and in particular to a high-strength light diffusion back plate and a preparation method thereof. Background Art

[0002] In the prior art, polystyrene resin (PS), styrene-methyl methacrylate copolymer resin (MS), polymethyl methacrylate (PMMA), and polycarbonate resin (PC) can all be used as light diffusion backplanes. PS tends to turn yellow after continuous heating; PMMA has good weather resistance, but is easily deformed by moisture; PC has excellent performance, but is expensive and difficult to process. MS, as a copolymer of methyl methacrylate (MMA) and styrene (S), has good heat resistance and dimensional retention. However, MS is brittle, and its flexibility, heat resistance, and dimensional stability are poor when used as a light diffusion backplane.

[0003] With the development of the LED industry, the demand for LED lights in displays has increased, which has put forward higher requirements on the toughness, heat resistance and dimensional stability of the diffusion plate. At present, there is no report on the research on using glass fiber to modify MS and use it as a light diffusion backplane. Summary of the invention

[0004] The problem in the prior art is that MS is brittle and has poor flexibility when used as a light diffusion backplane. In view of the above technical problems, the present invention provides a high-strength light diffusion backplane, which comprises the following components by weight:

[0005] MS 50-90%;

[0006] MBS 0-20%;

[0007] Glass fiber 10-30%;

[0008] Antioxidant 0.1-0.5%;

[0009] Lubricant 0.1-0.3%.

[0010] Preferably, the weight ratio of MS is 65-85%.

[0011] Preferably, the weight ratio of the MBS is 0-15%.

[0012] Preferably, the weight ratio of the glass fiber is 10-20%.

[0013] Preferably, the glass fibers are chopped glass fibers, and the average chopped length is 1-3 mm.

[0014] Preferably, the antioxidant comprises one or a combination of two or more of aromatic amine antioxidants, hindered phenol antioxidants, and phosphite antioxidants.

[0015] Preferably, the aromatic amine antioxidant includes BHA, BHT, TBHA, DPHP or DPPD.

[0016] Preferably, the hindered phenol antioxidant includes antioxidant 1010, antioxidant 1076 or antioxidant 3114.

[0017] Preferably, the phosphite antioxidant includes antioxidant 168 or antioxidant 626.

[0018] Preferably, the lubricant includes at least one of fatty acid amides, fatty acids, hydrocarbons, alcohols, metal soaps, and composite lubricants.

[0019] Preferably, the high-intensity light diffusion backplane is obtained by extruding the raw materials by side feeding, and specifically comprises the following steps:

[0020] Under light-proof conditions, all raw materials except glass fiber are first mixed uniformly and added to a screw extruder. The mixed material is heated and melted by a screw, and then continuously extruded from a main feed port toward an extruder discharge port to obtain a composite material. The obtained composite material is cooled and solidified, melt-extruded, and roll-formed to obtain a high-strength light diffusion backplane. During the screw extrusion process, glass fiber is added through a side feeding port provided on a barrel of the screw extruder, the horizontal distance between the side feeding port and the main feeding port is 101-105 cm, the horizontal distance between the main feeding port and the extruder discharge port is 228-230 cm, and the screw diameter is 35-65 mm.

[0021] Preferably, the extrusion temperature is 200°C-240°C.

[0022] Preferably, the feeding speed of the main feeding port is 25-28 rpm, and the feeding speed of the side feeding port is 7-10 rpm.

[0023] The present invention has the following beneficial effects:

[0024] (1) The present invention adds chopped glass fibers to the MS resin matrix by side feeding, and the obtained high-strength light diffusion backplane has better toughness, heat resistance and dimensional stability;

[0025] (2) The present invention further improves the toughness, heat resistance and dimensional stability of the obtained high-strength light diffusion backsheet by preferably selecting the chopped glass fibers as ECS303W-1.7-K or ECS304A-1.7-K;

[0026] (3) The present invention further improves the comprehensive performance of the obtained high-strength light-diffusing backplane by optimizing the length of the chopped glass fibers to be about 1.7 mm. DETAILED DESCRIPTION

[0027] The present invention is described in detail below with reference to the examples. However, it should be understood that the following examples are only illustrative of the embodiments of the present invention, and are not intended to limit the scope of the present invention.

[0028] The high-intensity light-diffusing backsheets obtained in the following Examples 1-3 of the present invention are obtained by extruding the raw materials by side-feeding, and the specific steps are as follows:

[0029] Under light-proof conditions, the raw materials except the glass fiber are first mixed uniformly and added to the screw extruder. The mixed material is heated by the screw for melt blending and screw extruded from the main feed port toward the extruder discharge port to obtain a composite material. The obtained composite material is cooled and solidified, melt extruded, and roll-formed to obtain a high-strength light diffusion backplane with a thickness of 2 mm. During the screw extrusion process, the glass fiber is added through the side feeding port provided on the barrel of the screw extruder. The horizontal distance between the side feeding port and the main feeding port is 101 cm, and the horizontal distance between the main feeding port and the extruder discharge port is 228 cm. The screw diameter is 65 mm; the extrusion temperature is 200°C; the feeding speed of the main feeding port is 25 rpm, and the feeding speed of the side feeding is 7 rpm; the melting temperature is 200°C, and the three-roller roll forming temperatures are 100°C for the front roller, 120°C for the middle roller, and 100°C for the rear roller.

[0030] The chopped glass fibers ECS303W-1.7-K, ECS307AT-3-M4, and ECS304A-1.7-K in the following embodiments of the present invention are all purchased from Chongqing International Composite Materials Co., Ltd.

[0031] Example 1

[0032] A high-strength light-diffusing back sheet, which has the following components by weight:

[0033]

[0034] The glass fiber is chopped glass fiber ECS304A-1.7-K, and the average length is 1.7 mm.

[0035] The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1.

[0036] The lubricant is lubricant PETS.

[0037] Example 2

[0038] A high-strength light-diffusing back sheet, which has the following components by weight:

[0039]

[0040] The glass fiber is chopped glass fiber ECS304A-1.7-K, and the average length is 1.7 mm.

[0041] The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1.

[0042] The lubricant is lubricant PETS.

[0043] Example 3

[0044] A high-strength light-diffusing back sheet, which has the following components by weight:

[0045]

[0046] The glass fiber is chopped glass fiber ECS304A-1.7-K, and the average length is 1.7 mm.

[0047] The antioxidant is a mixture of antioxidant 1010 and antioxidant 168 in a mass ratio of 1:1.

[0048] The lubricant is lubricant PETS.

[0049] Example 4 is the same as Example 3, except that the glass fiber length of the chopped glass fiber ECS304A-1.7-K in Example 4 is 3 mm.

[0050] Example 5 is the same as Example 3, except that the glass fiber length of the chopped glass fiber ECS304A-1.7-K in Example 5 is 6 mm.

[0051] Example 6 is the same as Example 3, except that the glass fiber in Example 6 is chopped glass fiber ECS307AT-3-M4.

[0052] Example 7 is the same as Example 3, except that the glass fiber in Example 7 is chopped glass fiber ECS303W-1.7-K.

[0053] Example 8 is the same as Example 3, except that the glass fiber in Example 8 is ground glass fiber EMG11-100, the average particle size of the glass fiber is 9 μm, and it is purchased from Chongqing International Composite Materials Co., Ltd.

[0054] Comparative Example 1 is the same as Example 3, except that Comparative Example 1 is commercially available styrene-methyl methacrylate copolymer resin MS800 purchased from Nippon Electric Chemical Co., Ltd.

[0055] Comparative Example 2 is the same as Example 3, except that Comparative Example 2 is commercially available polystyrene resin PS535N purchased from Guo'en Yisu (Zhejiang) New Material Technology Co., Ltd.

[0056] Performance Testing

[0057] The high-intensity light diffusion backplanes obtained in the embodiments of the present invention and the comparative examples were tested for relevant performances. The specific test results are shown in Table 1 and Table 1.

[0058] Light transmittance: The test standard is ASTM D1003. Light transmittance ≥ 56% can meet the requirements for diffuser plates.

[0059] Flexural modulus, flexural strength: The test standard is ASTM D790.

[0060] Breaking strength: The test standard is ASTM D638.

[0061] Impact strength: The test standard is ASTM D256.

[0062] Heat Deflection Temperature: The test standard is ASTM D1525.

[0063] Table 1

[0064]

[0065] Table 1

[0066]

[0067] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A high-intensity light diffusion backplane, characterized in that: The composition includes the following ingredients by weight:

2. The high-intensity light diffusion backplane according to claim 1, characterized in that: The glass fibers are chopped glass fibers, and the average chopped length is 1-3 mm.

3. The high-intensity light diffusion backplane according to claim 1, characterized in that: The antioxidant comprises one or a combination of two or more of aromatic amine antioxidants, hindered phenol antioxidants and phosphite antioxidants.

4. The high-intensity light diffusion backplane according to claim 3, characterized in that: The aromatic amine antioxidant includes BHA, BHT, TBHA, DPHP or DPPD.

5. The high-intensity light diffusion backplane according to claim 3, characterized in that: The hindered phenol antioxidant includes antioxidant 1010, antioxidant 1076 or antioxidant 3114.

6. The high-intensity light diffusion backplane according to claim 3, characterized in that: The phosphite antioxidant includes antioxidant 168 or antioxidant 626.

7. The high-intensity light diffusion backplane according to claim 1, characterized in that: The lubricant includes at least one of fatty acid amides, fatty acids, hydrocarbons, alcohols, metal soaps, and composite lubricants.

8. A high-intensity light-diffusing backplane according to any one of claims 1 to 7, characterized in that: The raw materials are blended and extruded to obtain a sheet by side feeding, which specifically includes the following steps: Under light-proof conditions, all raw materials except glass fiber are first mixed uniformly and added to a screw extruder. The mixed material is heated and melted by a screw, and then continuously extruded from a main feed port toward an extruder discharge port to obtain a composite material. The obtained composite material is cooled and solidified, melt-extruded, and roll-formed to obtain a high-strength light diffusion backplane. During the screw extrusion process, glass fiber is added through a side feeding port provided on a barrel of the screw extruder, the horizontal distance between the side feeding port and the main feeding port is 101-105 cm, the horizontal distance between the main feeding port and the extruder discharge port is 228-230 cm, and the screw diameter is 35-65 mm.

9. The high-intensity light diffusion backplane according to claim 8, characterized in that: The extrusion temperature is 200°C-240°C.

10. The high-intensity light diffusion backplane according to claim 8, characterized in that: The feeding speed of the main feeding port is 25-28rpm, and the feeding speed of the side feed is 7-10rpm.

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