Single-layer skinning foaming diffusion plate and preparation method thereof

Abstract

The invention relates to the technical field of light diffusion plates, in particular to a single-layer skinning foaming diffusion plate and a preparation method thereof. The single-layer skinning foaming diffusion plate is formed by uniformly mixing and then extruding the following raw materials: 88-96% of a plastic base material, 1-20% of a toughening agent, 0.1-1% of an antioxidant, 0.1-1% of an organic silicon diffusion agent, 0.01-1% of a foaming agent and 0.01-0.15% of a nucleating agent, and the mass ratio of the toughening agent to the foaming agent is 1: (0.01-0.1). According to the present invention, the toughening agent is introduced into the raw materials of the single-layer skinning foaming diffusion plate, such that the brittleness of the diffusion plate can be reduced, the impact resistance of the diffusion plate can be improved, and the use amount ratio of the toughening agent to the foaming agent is strictly controlled within the range of 1: (0.005-0.01) through the matching modification of the toughening agent and the foaming agent so as to achieve the effect of the single-layer skinning foaming diffusion plate; the single-layer skinning foaming diffusion plate with a small thickness can be prepared by combining the raw materials with other raw materials such as an antioxidant and a nucleating agent, and the single-layer skinning foaming diffusion plate is good in mechanical property, low in manufacturing cost and excellent in foaming effect and optical performance.

Description

Technical Field

[0001] The present invention relates to the technical field of light diffusion plates, and in particular to a single-layer crusted foamed diffusion plate and a preparation method thereof. Background Art

[0002] Light diffusion materials are key components in LED lighting and display applications. Because LEDs are point light sources, concentrated light can produce glare. Therefore, light diffusion materials are needed to diffuse the point light source into a surface light source. Traditional light diffusion materials use organic or inorganic high-refractive index materials, such as titanium dioxide, calcium carbonate, silicone microspheres, and PMMA microspheres. These materials are added to the substrate to achieve the desired light diffusion effect.

[0003] However, these light-diffusing materials inevitably produce light absorption and scattering losses, reducing light extraction efficiency. To avoid these issues, gas-based light-diffusing bubble sheets have begun to be used. Because the refractive index of gas is 1, light undergoes total internal reflection at the solid-gas interface, changing the light's path without absorbing photons. Consequently, the light efficiency and uniformity of these bubble sheets are significantly improved compared to traditional light-diffusing sheets. Currently, commonly used foaming agents for these bubble sheets include carbonates, azodicarbonamides, and benzenesulfonylhydrazides.

[0004] However, this type of bubble board also has the following disadvantages: after the plastic substrate is foamed, there will be a problem of decreased mechanical properties. At present, a sandwich interlayer method is adopted, in which the foaming layer is sandwiched in the middle to prevent the plastic from being too brittle and breaking. For example, patent CN202210434579.7 "A multi-layer co-extruded foaming diffusion plate and its preparation method and application" is finally made into a foaming diffusion plate by a multi-layer co-extrusion process from a main base layer (containing a foaming agent) and a protective layer arranged on both sides of the main base layer. However, the existing sandwich interlayer process, since the thickness of the protective layer needs to be controlled at about 0.1mm, it is difficult to control the extrusion amount of the protective layer (epidermis) and the foaming layer in actual production, resulting in uneven thickness, and the problem of uneven optical properties will still occur. In addition, since the above-mentioned sandwich interlayer structure has a protective layer, a main base layer and a protective layer stacked in sequence, it is difficult to make the thickness of the material thin. Usually, the thickness of the entire bubble board is above 1.0mm, which increases the material cost. Summary of the Invention

[0005] The main purpose of the present invention is to provide a single-layer skinned foam diffuser plate and its preparation method, aiming to improve the problems of uneven thickness and uneven optical properties of existing multi-layer co-extruded foam diffuser plates. At the same time, it also solves the technical problems of large finished product thickness and high production cost of existing multi-layer co-extruded foam diffuser plates.

[0006] To achieve the above objectives, the present invention proposes a single-layer crust foam diffuser, which is extruded after mixing the following raw materials: 88-96% plastic base material, 1-20% toughening agent, 0.1-1% antioxidant, 0.1-1% silicone diffuser, 0.01-1% foaming agent, and 0.01-0.15% nucleating agent, wherein the mass ratio of the toughening agent to the foaming agent is 1:0.01-0.1.

[0007] Preferably, the toughening agent comprises at least one of styrene-butadiene-styrene block copolymer, styrene-butadiene resin, methyl methacrylate-butadiene-styrene terpolymer, thermoplastic elastomer or thermoplastic polyurethane.

[0008] Preferably, the foaming agent includes at least one of sodium bicarbonate, magnesium bicarbonate, calcium carbonate, azodicarbonamide, citric acid, and sodium citrate.

[0009] Preferably, the nucleating agent includes at least one of magnesium silicate, sodium citrate, sodium oxalate, alumina, nano-silicon dioxide, nano-titanium dioxide or silicone oil.

[0010] Preferably, the antioxidant includes at least one of butylated hydroxyanisole, butylated hydroxytoluene, tert-butylhydroquinone, diisodecylphenyl phosphite, pentaerythritol bisphosphite, bis(2,2,6,6-tetramethylpiperidinyl)sebacate, tris(2,4-di-tert-butylphenyl)phosphite, and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

[0011] Preferably, the thickness of the single-layer skinned foam diffuser plate is 0.6-3.0 mm.

[0012] Preferably, the plastic substrate is GPPS polystyrene.

[0013] In addition, the present invention also proposes a method for preparing a single-layer crust foam diffuser plate, comprising the following steps: uniformly mixing the raw materials of the single-layer crust foam diffuser plate according to a ratio to form a mixed material, extruding the mixed material through an extrusion device to obtain a polymer melt, and subjecting the polymer melt to three-roll molding, and then cooling, shaping, and post-processing to obtain the single-layer crust foam diffuser plate.

[0014] Preferably, the extrusion temperature of the extrusion equipment is 190-240°C, and the die outlet temperature of the extrusion equipment is 220-250°C.

[0015] Preferably, after the polymer melt is extruded from the extrusion equipment, it is sequentially passed through an embossing front roller, an embossing middle roller, and an embossing rear roller for three-roll forming;

[0016] The roughness Ra of the embossing front roller is 10-20 μm, and the roller temperature of the embossing front roller is 100-140° C.

[0017] The roughness Ra of the embossing roller is 7-12 μm, and the roller temperature of the embossing roller is 90-130° C.

[0018] The roughness Ra of the embossing roller is 20-40 μm, and the roller temperature of the embossing roller is 70-105° C.

[0019] Compared with the prior art, the single-layer skinned foamed diffuser plate and its preparation method of the present invention have the following advantages:

[0020] Beneficial effects:

[0021] 1. This solution introduces a toughening agent into the raw materials of the single-layer crust foamed diffuser plate to reduce the brittleness of the diffuser plate and improve the impact resistance of the diffuser plate. At the same time, through the coordinated modification of the toughening agent and the foaming agent, the usage ratio of the toughening agent and the foaming agent is strictly controlled within the range of 1: (0.005-0.01). In combination with other raw materials such as antioxidants and nucleating agents, a single-layer crust foamed diffuser plate with a smaller thickness can be produced, which has better mechanical properties, lower production costs, and excellent foaming effect and optical properties.

[0022] 2. In terms of the production method, this solution strictly controls the die outlet temperature of the extruder die head to 220-250°C, thereby controlling the foaming effect during extrusion of the single-layer skin-crusted foam diffuser sheet, ensuring that the bubbles generated are of appropriate size and are not prone to rupture, further improving the optical properties of the single-layer skin-crusted foam diffuser sheet. Furthermore, after exiting the die, the polymer melt passes through three embossing rollers: a front embossing roller, a middle embossing roller, and a rear embossing roller. This results in a matte finish for the single-layer skin-crusted foam diffuser sheet, which has excellent diffusion effects and superior optical properties. DETAILED DESCRIPTION

[0023] The following is a clear and complete description of the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of them. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are within the scope of protection of the present invention.

[0024] In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the fact that ordinary technicians in this field can implement them. When the combination of technical solutions is mutually contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0025] A single-layer crust foam diffuser plate is formed by mixing the following raw materials, calculated by mass percentage, and then extruding: 88-96% of a plastic base material, 1-20% of a toughening agent, 0.1-1% of an antioxidant, 0.1-1% of an organosilicon diffuser, 0.01-1% of a foaming agent, and 0.01-0.15% of a nucleating agent, wherein the mass ratio of the toughening agent to the foaming agent is 1:(0.01-0.1); the thickness of the single-layer crust foam diffuser plate is 0.6-3.0 mm.

[0026] The toughening agent includes at least one of styrene-butadiene-styrene block copolymer (SBS), styrene-butadiene resin, methyl methacrylate-butadiene-styrene terpolymer (MBS), thermoplastic elastomer (TPE) or thermoplastic polyurethane (TPU); the foaming agent includes at least one of sodium bicarbonate, magnesium bicarbonate, calcium carbonate, azodicarbonamide, citric acid, and sodium citrate; the nucleating agent includes at least one of magnesium silicate, sodium citrate, sodium oxalate, aluminum oxide, nano silicon dioxide, nano titanium dioxide or silicone oil; The antioxidant includes at least one of butylated hydroxyanisole, butylated hydroxytoluene, tert-butylhydroquinone, diisodecylphenyl phosphite, pentaerythritol bisphosphite, bis(2,2,6,6-tetramethylpiperidinyl)sebacate (antioxidant 770), tris(2,4-di-tert-butylphenyl)phosphite (antioxidant 168), and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate] (antioxidant 1010); the plastic substrate is GPPS (polystyrene) and has good optical properties and processing properties.

[0027] The single-layer crust foam diffuser in this solution can be applied to various display and lighting fields, and is particularly suitable for use as a light diffusion backplane for lamps or display screens.

[0028] Specifically, a toughening agent is introduced into the raw materials of the single-layer crust foamed diffuser plate, which can reduce the brittleness of the diffuser plate and improve the impact resistance of the diffuser plate. At the same time, through the coordinated modification of the toughening agent and the foaming agent, the usage ratio of the toughening agent and the foaming agent is strictly controlled within the range of 1: (0.01-0.1). In combination with the use of other raw materials such as antioxidants and nucleating agents, there is no need to adopt the sandwich structure of the existing multi-layer co-extruded foamed diffuser plate. A single-layer crust foamed diffuser plate can be made, which has good overall mechanical properties, low production cost, and thin thickness, which can be as low as 0.5 mm. At the same time, the single-layer crust foamed diffuser plate also has excellent foaming effect and optical properties.

[0029] In addition, the present invention also proposes a method for preparing a single-layer crust foam diffuser plate, comprising the following steps: uniformly mixing the raw materials of the single-layer crust foam diffuser plate according to a ratio to form a mixed material, extruding the mixed material through an extrusion device to obtain a polymer melt, and then subjecting the polymer melt to three-roll molding and cooling and shaping to obtain the single-layer crust foam diffuser plate.

[0030] Among them, the extrusion temperature of the extrusion equipment is 190-240°C, and the die outlet temperature of the extrusion equipment is 220-250°C; after the polymer melt is extruded from the extrusion equipment, it passes through an embossing front roller, an embossing middle roller, and an embossing rear roller in sequence for three-roll forming; the roughness Ra of the embossing front roller is 10-20 μm, and the roller temperature of the embossing front roller is 100-140°C; the roughness Ra of the embossing middle roller is 7-12 μm, and the roller temperature of the embossing middle roller is 90-130°C; the roughness Ra of the embossing rear roller is 20-40 μm, and the roller temperature of the embossing rear roller is 70-105°C.

[0031] In the preparation method, the raw materials of the single-layer crust foaming diffusion plate are mixed and first extruded through an extrusion device (extruder). The specific melting temperature is 190-240°C. The extruder includes one zone, two zones, three zones, four zones, five zones, six zones, eight zones, nine zones, a screen changer, a metering pump and a die head device. Among them, the heating temperature of zone one is 190°C-205°C, the heating temperature of zone two is 195°C-210°C, the heating temperature of zone three is 200°C-220°C, the heating temperature of zone four is 210°C-230°C, the heating temperature of zone five is 220°C-240°C, and the heating temperature of zone six is ​​220°C-2 The heating temperature of the seventh zone is 210-230°C, the heating temperature of the eighth zone is 210-230°C, the heating temperature of the ninth zone is 210-230°C, the heating temperature of the screen changer is 210-230°C, the heating temperature of the metering pump is 220-240°C, the heating temperature of the die device is 210-250°C, and this scheme strictly controls the die outlet temperature of the extruder die device to be 220-250°C, thereby controlling the foaming effect of the single-layer crust foam diffuser during extrusion, making the generated bubbles of appropriate size and not easy to break, and ultimately improving the optical properties of the single-layer crust foam diffuser.

[0032] After the polymer melt comes out of the die mouth, it passes through three embossing rollers, namely the embossing front roller, the embossing middle roller and the embossing rear roller. During three-roller forming, the roughness and roller temperature of the embossing front roller, the embossing middle roller and the embossing rear roller need to be controlled within an appropriate range. Specifically, the roughness Ra of the embossing front roller is 10-20μm, the roller temperature is 100-140℃, the roughness Ra of the embossing middle roller is 7-12μm, the roller temperature is 90-130℃, the roughness Ra of the embossing rear roller is 20-40μm, and the roller temperature of the embossing rear roller is 70-105℃. The Rz of the diffuser plate obtained after passing through this roller is about 20-50μm, so that the obtained single-layer crusted foam diffuser plate is matte, with better diffusion effect and excellent optical properties. In addition, the discharge speed and spacing of the embossing roller can also be controlled. Usually, the discharge speed is adjusted within the range of 1-30r / min according to the different thicknesses of the light diffuser plate, and the spacing can be adjusted within the range of 0.5 to 3.0mm.

[0033] The technical solutions of the present invention are further described in detail below in conjunction with specific embodiments. It should be understood that the following embodiments are only used to explain the present invention and are not used to limit the present invention.

[0034] Comparative Example 1

[0035] A method for preparing a single-layer foamed diffuser plate comprises the following steps: uniformly mixing, by weight, 100 parts of polystyrene, 0.02 parts of a foaming agent (sodium bicarbonate), 3 parts of a light diffuser, 7 parts of titanium dioxide, 2 parts of an anti-UV agent (UV531), and 1 part of an antioxidant to form a mixture; extruding the mixture through an extruder (at an extrusion temperature of 190-240° C. and a die outlet temperature of 220° C.) to obtain a polymer melt; and shaping the polymer melt through embossing rollers (with three rollers having roughnesses of 8 μm, 16 μm, and 20 μm and roller temperatures of 100° C., 100° C., and 100° C.); and then cooling, shaping, and post-processing to obtain a single-layer foamed diffuser plate with a thickness of 0.8 mm.

[0036] Example 1

[0037] The preparation steps and parameters in this embodiment are the same as those in Comparative Example 1, except that the raw materials of the single-layer crust foamed diffuser plate of this scheme specifically include: 95.37% GPPS, 3% toughening agent (SBS butadiene-styrene resin), 0.3% antioxidant - [3-(2,4-di-tert-butylphenyl) propionate] pentaerythritol ester and 0.3% tris(2,4-di-tert-butylphenyl) phosphite, 1% silicone diffuser, 0.02% foaming agent (sodium bicarbonate), and 0.01% nucleating agent (sodium citrate).

[0038] Example 2

[0039] A preparation method for a single-layer skinned foamed diffuser plate comprises the following steps: uniformly mixing 93.87% of GPPS, 5% of a toughening agent SEBS (styrene-butadiene-styrene block copolymer), 0.5% of an antioxidant (butylated hydroxytoluene), 0.5% of an organosilicon diffuser, 0.03% of a foaming agent (sodium bicarbonate), 0.05% of a nucleating agent light calcium carbonate, and 0.05% of nano-titanium dioxide to form a mixture; extruding the mixture through an extruder (extrusion temperature of 190-240° C., die outlet temperature of 245° C.) to obtain a polymer melt; and shaping the polymer melt through an embossing roller (roughness Ra of 10 μm, roller temperature of 70-120° C.). After cooling, shaping, and post-processing, a single-layer skinned foamed diffuser plate with a thickness of 0.8 mm is obtained.

[0040] Example 3

[0041] A preparation method for a single-layer skinned foamed diffuser plate comprises the following steps: forming a mixture of 93.82% GPPS, 5% toughening agent (thermoplastic polyurethane), 0.5% antioxidant (pentaerythritol diphosphite), 0.5% organosilicon diffuser, 0.03% foaming agent (sodium bicarbonate), and nucleating agent (0.1% nano-silicon dioxide and 0.05% nano-titanium dioxide); extruding the mixture through an extruder (extrusion temperature of 190-240° C., die outlet temperature of the extruder of 240° C.) to obtain a polymer melt; passing the polymer melt through an embossing roller (roughness Ra of 12 μm, roller temperature of 70-120° C.), and then cooling, shaping, and post-processing to obtain a single-layer skinned foamed diffuser plate with a thickness of 0.8 mm.

[0042] The single-layer foamed diffusion plates prepared in Examples 1-3 and Comparative Example 1 were subjected to the following performance tests, and the specific test results are shown in the following table:

[0043]

[0044] From the test results of Comparative Example 1 and Example 1 in the above table, it can be seen that directly using the existing foam diffuser material to make a single-layer foam diffuser, the corresponding finished product has poor impact resistance (bubble diameter greater than 240 μm, bubble number greater than 180 / cm 2 , impact strength less than 8 J / cm2), and a qualified diffuser plate product cannot be obtained. After using the single-layer crust foam diffuser plate raw materials of this solution in Example 1, due to the adjustment of the raw material components and ratios, and the strict restriction of the mass ratio of the foaming agent and the toughening agent, the impact resistance of the single-layer crust foam diffuser plate produced is improved, and a single-layer crust foam diffuser plate with a smaller thickness and better performance can be produced.

[0045] The performance test results of the single-layer crust foam diffuser obtained in Examples 1-3 show that the single-layer crust foam diffuser of this solution has a good foaming effect, with a bubble diameter of ≥100 μm and a bubble number of ≥150 / cm 2 , impact strength ≥11J / cm2, transmittance above 45%, haze around 93%, optical properties meet standard requirements, and mechanical properties are better.

[0046] Example 4

[0047] The preparation steps and parameters in this embodiment are the same as those in Example 2, except that the amount of toughening agent / foaming agent used, i.e., the mass ratio, is different. See the table below for details:

[0048]

[0049]

[0050] The performance of the diffuser plate prepared in Example 4 was tested, and the specific test results are shown in the following table:

[0051]

[0052]

[0053] From the test data in the above table, it can be seen that when the mass ratio of toughening agent to foaming agent is preferably 1:(0.01-0.1), products with an impact strength of more than 11 J / cm2 can be produced. The mass ratio of toughening agent to foaming agent is more preferably 1:(0.05-0.1). Within this range, the size of the bubbles generated in the diffuser plate is appropriate, and the number of bubbles is controlled at 150-270 / cm2. 2 range, has good light diffusion effect, and the impact strength can be maintained above 11J / cm2, with better mechanical properties.

[0054] Example 5

[0055] The preparation steps and parameters in this embodiment are the same as those in Example 1, except that the types of toughening agents are different, specifically:

[0056]

[0057] The single-layer skinned foamed diffuser plate prepared in Example 5 was subjected to performance testing, and the specific test results are shown in the following table:

[0058]

[0059]

[0060] As can be seen from the test data in the table above, the toughening agent of this solution is preferably a composite toughening agent of methyl methacrylate-butadiene-styrene terpolymer and thermoplastic polyurethane. The compounding effect of the toughening agent with the foaming agent is good, the size of the bubbles generated in the diffusion plate is appropriate, and the number of bubbles can be controlled at 189 / cm 2 It has a good light diffusion effect, and the impact strength can be maintained above 12J / cm2, with better mechanical properties.

[0061] Example 6

[0062] The preparation steps and parameters in this embodiment are the same as those in Example 1, except that the types and ratios of the foaming agents are different, specifically:

[0063]

[0064] The single-layer skinned foamed diffuser plate prepared in Example 6 was subjected to performance testing, and the specific test results are shown in the following table:

[0065]

[0066] As can be seen from the test data in the table above, the foaming agent of this solution is preferably a mixture of sodium bicarbonate, magnesium bicarbonate and azodicarbonamide. When used together with the toughening agent, the effect is better. The size of the bubbles generated in the diffusion plate is appropriate, and the number of bubbles can be controlled at 186 / cm 2 It has a good light diffusion effect, and the impact strength can be maintained above 12J / cm2, with better mechanical properties.

[0067] Example 7

[0068] The preparation steps and parameters in this embodiment are the same as those in Example 1, except that the die outlet temperature of the extruder is different, specifically:

[0069] Exit die temperature / ℃ Example 1 220 Example 7-1 210 Example 7-2 230 Example 7-3 240 Example 7-4 250

[0070] The single-layer skinned foamed diffuser plate prepared in Example 7 was subjected to performance testing, and the specific test results are shown in the following table:

[0071]

[0072] As can be seen from the test data in the table above, among the preparation parameters, the extruder outlet temperature of this solution is more preferably 240°C, the foaming effect is better, the bubble size generated in the diffusion plate is appropriate, the number of bubbles can be controlled at around 184 / cm2, it has a good light diffusion effect, the impact strength is close to 12J / cm2, and the mechanical properties are better.

[0073] Example 8

[0074] The preparation steps and parameters in this embodiment are the same as those in Example 1, except that the surface roughness of the embossing roller and the water cooling temperature of the roller are different. Specifically:

[0075] Front roller Ra Middle roller Ra Rear roller Ra Front roller water temperature Middle roller water temperature Rear roller water temperature Example 1 8μm 16μm 20μm 100℃ 100℃ 100℃ Example 8-1 16μm 8μm 20μm 130℃ 100℃ 90℃ Example 8-2 20μm 16μm 8μm 100℃ 100℃ 130℃ Example 8-3 16μm 20μm 8μm 100℃ 130℃ 100℃ Example 8-4 16μm 8μm 20μm 140℃ 130℃ 90℃

[0076] The single-layer skinned foamed diffuser plate prepared in Example 8 was subjected to performance testing, and the specific test results are shown in the following table:

[0077]

[0078] As can be seen from the test data in the above table, after the polymer melt of this scheme is extruded by the extruder, Examples 8-1 and 8-4 are preferred schemes, and are formed by three rollers, and the parameters of the embossing front roller, the embossing middle roller, and the embossing rear roller are preferably that the roughness Ra of the embossing front roller is 10-20 μm, and the roller temperature is 100-140°C; the roughness Ra of the embossing middle roller is 7-12 μm, and the roller temperature is 90-130°C; the roughness Ra of the embossing rear roller is 20-40 μm, and the roller temperature of the embossing rear roller is 70-105°C. At this time, the foaming effect is better, and the number of bubbles can be controlled at 150-200 / cm 2 The diffuser plate has a large surface Rz and is matte, which has a good light diffusion effect.

[0079] Example 9

[0080] A method for preparing a single-layer crust foaming diffusion plate comprises the following steps: 88.25%, 10% of a toughening agent (methyl methacrylate-butadiene-styrene terpolymer and styrene-butadiene-styrene block copolymer, and the mass ratio of the two is 1:1), 0.3% of an antioxidant - pentaerythritol [3-(2,4-di-tert-butylphenyl) propionate] and 0.3% of tris(2,4-di-tert-butylphenyl) phosphite, 0.5% of an organic silicon diffuser, 0.5% of a foaming agent (sodium bicarbonate, magnesium bicarbonate, azodicarbonamide and 2,2'-azobisisobutyronitrile, and the mass ratio of the three is 1:0.5:0.2), and a nucleating agent (0.1% of nano-silica and 0.05% of nano-titanium dioxide) are mixed uniformly to form a mixture, the mixture is extruded through an extruder to obtain a polymer melt, the polymer melt is formed by an embossing roller, and then cooled, shaped and post-treated to obtain a single-layer crusted foamed diffuser plate.

[0081] Among them, the extrusion temperature of the extruder is 190-240℃, and the die outlet temperature of the extruder is 240℃; after the polymer melt is extruded from the extrusion equipment, it passes through the embossing front roller, embossing middle roller, and embossing rear roller in sequence for three-roller forming; the roughness Ra of the embossing front roller is 16μm, and the roller temperature is 140℃; the roughness Ra of the embossing middle roller is 10μm, and the roller temperature is 100℃; the roughness Ra of the embossing rear roller is 20μm, and the roller temperature is 105℃.

[0082] The single-layer skinned foamed diffuser plate prepared in Example 9 was subjected to performance testing, and the specific test results are shown in the following table:

[0083]

[0084] The test results in the table above show that, in terms of formulation, by optimizing the types of toughening agents and foaming agents while strictly limiting the mass ratio of the two, and in terms of preparation process, by adjusting the extruder's die temperature and limiting the specific roughness and roller temperature of the embossing front roller, embossing middle roller, and embossing rear roller, the impact strength of the single-layer crusted foamed diffuser plate can reach over 12J / cm2 even when the thickness is reduced to 0.8mm. Even if the thickness is reduced to 0.6mm, the impact strength can still reach over 9J / cm2, indicating excellent mechanical properties. At the same time, the bubble diameter inside the diffuser plate is 150-190μm, and the number of bubbles is 140-260 / cm2. 2 , with excellent optical properties.

[0085] The above description is only a preferred embodiment of the present invention and does not limit the patent scope of the present invention. All equivalent structural transformations made by using the contents of the present invention specification under the inventive concept of the present invention, or direct / indirect application in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A single-layer crust foam diffuser plate, characterized in that: The single-layer skinned foam diffuser plate is formed by mixing the following raw materials and then extruding them: 88-96% of plastic base material, 1-20% of toughening agent, 0.1-1% of antioxidant, 0.1-1% of silicone diffuser, 0.01-1% of foaming agent, and 0.01-0.15% of nucleating agent, wherein the mass ratio of the toughening agent to the foaming agent is 1:(0.01-0.1).

2. The single-layer skinned foam diffuser plate according to claim 1, characterized in that: The toughening agent includes at least one of styrene-butadiene-styrene block copolymer, styrene-butadiene resin, methyl methacrylate-butadiene-styrene terpolymer, thermoplastic elastomer or thermoplastic polyurethane.

3. The single-layer skinned foam diffuser plate according to claim 1, characterized in that: The foaming agent includes at least one of sodium bicarbonate, magnesium bicarbonate, calcium carbonate, azodicarbonamide, citric acid, and sodium citrate.

4. The single-layer skinned foam diffuser plate according to claim 1, characterized in that: The nucleating agent includes at least one of magnesium silicate, sodium citrate, sodium oxalate, aluminum oxide, nano silicon dioxide, nano titanium dioxide or silicone oil.

5. The single-layer skinned foam diffuser plate according to claim 1, characterized in that: The antioxidant includes at least one of butylated hydroxyanisole, butylated hydroxytoluene, tert-butylhydroquinone, diisodecylphenyl phosphite, pentaerythritol bisphosphite, bis(2,2,6,6-tetramethylpiperidinyl)sebacate, tris(2,4-di-tert-butylphenyl)phosphite, and pentaerythritol tetrakis[β-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate].

6. The single-layer skinned foam diffuser plate according to claim 1, characterized in that: The thickness of the single-layer skinned foamed diffuser plate is 0.6-3.0 mm.

7. The single-layer skinned foam diffuser plate according to claim 1, characterized in that: The plastic substrate is polystyrene.

8. A method for preparing a single-layer skinned foamed diffuser plate according to any one of claims 1 to 7, characterized in that: The method comprises the following steps: uniformly mixing raw materials of a single-layer skinned foamed diffuser plate according to a proportion to form a mixed material; extruding the mixed material through an extrusion device to obtain a polymer melt; forming the polymer melt through three rollers; and cooling, shaping, and post-processing to obtain the single-layer skinned foamed diffuser plate.

9. The method for preparing a single-layer skinned foamed diffuser plate according to claim 8, characterized in that: The extrusion temperature of the extrusion equipment is 190-240°C, and the die outlet temperature of the extrusion equipment is 220-250°C.

10. The method for preparing a single-layer crusted foamed diffuser plate according to claim 8, characterized in that: After the polymer melt is extruded from the extrusion equipment, it is sequentially passed through an embossing front roller, an embossing middle roller, and an embossing rear roller for three-roll forming; The roughness Ra of the embossing front roller is 10-20 μm, and the roller temperature of the embossing front roller is 100-140° C. The roughness Ra of the embossing roller is 7-12 μm, and the roller temperature of the embossing roller is 90-130° C. The roughness Ra of the embossing roller is 20-40 μm, and the roller temperature of the embossing roller is 70-105° C.

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