Low-reflectivity full-dull black paint and preparation method thereof

Abstract

The invention relates to the technical field of paint, in particular to low-reflectivity full-dull black paint for a vehicle-mounted HUD system and a preparation method of the low-reflectivity full-dull black paint. The low-reflectivity full-dull black paint is used on a vehicle-mounted HUD light source cover (base material PC + PBT) to replace current mainstream black flocked cloth, the black paint selects resin with good chemical resistance and adhesive force and is matched with pigment and filler with high light absorption efficiency and large specific surface area to prepare the dull black paint with the reflectivity lower than 1.0, and the black paint is good in chemical resistance, good in aging resistance and good in weather resistance. And after being used for several years, the display definition cannot be reduced, and the performance can meet the requirements of customers.

Description

Technical Field

[0001] The invention relates to the technical field of coatings, and in particular to a low-reflectivity full-matt black paint for a vehicle-mounted HUD system and a preparation method thereof. Background Art

[0002] At present, the method of absorbing reflected light from the light source in the vehicle HUD (Head Up Display) system on the market mainly uses black flocking cloth. Because the black flocking cloth used in the vehicle has poor aging resistance, it will lose hair, age and become brittle after a few years of use, and finally become powdery, and the ability to absorb light will decrease, resulting in a decrease in the clarity of the HUD display and affecting the display effect. Therefore, it is necessary to develop a product that can replace the mainstream black flocking cloth currently used. Summary of the invention

[0003] The substrate of the vehicle-mounted HUD light source cover is generally PC+PBT. Therefore, the purpose of the present invention is to provide a low-reflectivity full-matt black paint for a vehicle-mounted HUD system and provide a preparation method thereof to replace the current mainstream black flocking cloth. The black paint has a reflectivity lower than 1.0, good chemical resistance and aging resistance, and the display clarity will not decrease after several years of use.

[0004] To achieve the above object, the present invention adopts the following technical solutions:

[0005] A low-reflectivity full-matt black paint is a two-component system, comprising an A component and a B component in a mass ratio of 10:(7-11), wherein the A component contains the following components in mass percentage: 25-38% of polycarbonate resin G3452, 10-15% of hydroxyl acrylic resin FS2451, 10-16% of propylene glycol methyl ether acetate, 20-30% of butyl ester, 3-6% of dispersant, 2-5% of high-pigment carbon black powder, 2-5% of carbon nanotubes, 5-10% of black elastic powder, 2-4% of matting powder, 2-5% of anti-settling agent, 0.3-0.8% of leveling agent, 0.2-0.5% of PU drying agent, 0.3-0.8% of ultraviolet light absorber, and 0.2-0.5% of ultraviolet light stabilizer; and the B component comprises a curing agent N3390 in a mass ratio of 1-3 and a diluent in an amount of 6-8.

[0006] Furthermore, the dispersant is S32500, the high-pigment carbon black powder is 5000, the carbon nanotube is TF210, the matting powder is OK520, the anti-settling agent is 4200-10, the leveling agent is BYK333, the PU drying agent is T-12, the ultraviolet absorber is TINUVIN 1130, and the ultraviolet stabilizer is INUVIN 292.

[0007] Furthermore, the diluent is a mixture of butyl acetate:ethyl acetate:propylene glycol methyl ether acetate = (45-55): (30-40): (10-20).

[0008] The preparation method of component A of the above-mentioned low-reflectivity full-matt black paint is as follows: polycarbonate resin, hydroxy acrylic resin, propylene glycol methyl ether acetate, a part of butyl ester, and dispersant are added in order, dispersed and stirred at 300 rpm for 5 minutes, and then high-pigment carbon black powder and carbon nanotubes are added in turn, stirred at 500 rpm for 30 minutes, and then transferred to a sand mill to grind to a fineness of less than 10 microns, and then black elastic powder and matting powder are added, dispersed and stirred at 600 rpm for 20 minutes, and finally anti-settling agent, leveling agent, PU drying agent, the remaining butyl ester, ultraviolet light absorber, and ultraviolet light stabilizer are added in turn, and dispersed and stirred at 300 rpm for 10 minutes.

[0009] The method of using the above-mentioned low-reflectivity full-matt black paint is: component A: curing agent: diluent = 10:1.5:6-8 oil opening ratio, viscosity: 8.5 seconds (Yantian 2# cup), spray on the surface of the substrate, bake at 70℃~80℃ for 30 minutes, and bake at 80℃*120 minutes after it comes off the line.

[0010] A substrate, the surface of which is coated with the above-mentioned low-reflectivity full-matt black paint, the substrate comprising PC+PBT material. The substrate is used for a light source cover of a vehicle-mounted head-up display system.

[0011] The present invention has the following beneficial effects:

[0012] The main polycarbonate resin G3452 used in the present invention has better weather resistance and chemical resistance, and better adhesion compared to other similar resins (such as: Bayer C1200 linear aliphatic polycarbonate polyester resin, Wanjie J-303 polycarbonate resin). The hydroxyl acrylic resin FS2451 used has improved performance, excellent interlayer adhesion, and excellent chemical resistance. High-pigment carbon black powder has good blackness and good light absorption effect. Carbon nanotubes have a high specific surface area, are porous, and have good light absorption effect. Black elastic powder has good blackness, good extinction effect, and good light absorption effect. The black paint adopts a two-component system. The resin system has strong adhesion to the substrate PC+PBT, as well as chemical resistance. It is matched with pigments and fillers with good weather resistance to ensure that the overall paint film has good chemical resistance and aging resistance.

[0013] The low reflectivity full matt black paint of the present invention is used on the vehicle HUD light source cover (substrate PC+PBT), replacing the current mainstream black flocking cloth. The black paint uses a resin with good chemical resistance and adhesion, and is matched with a pigment filler with high light absorption efficiency and large specific surface area to prepare a matt black paint with a reflectivity lower than 1.0. The black paint has good chemical resistance and aging resistance, and the display clarity will not decrease after several years of use, and the performance can meet the requirements of customers. Ordinary matt black paints on the market cannot meet the above requirements. DETAILED DESCRIPTION

[0014] The features and performance of the present invention are further described in detail below in conjunction with the embodiments. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments, and are not limitations of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0015] Unless otherwise specified, the test materials, reagents, methods and equipment used in the following examples are conventional test materials, reagents, methods and equipment in the technical field; unless otherwise specified, the test materials and reagents used in the following examples can be obtained from commercial channels.

[0016] Table 1 The dosage ratio of each component in Examples 1-3 (unit: weight parts)

[0017]

[0018] Among them, the formula table of component A in each embodiment is shown in Table 2.

[0019] Table 2 Formulation of component A of Examples 1-3 (unit: %)

[0020]

[0021] The preparation method of component A in the above embodiments is:

[0022] Add items 1 to 5 in order, stir at 300 rpm for 5 minutes, then add items 6 and 7 in order, stir at 500 rpm for 30 minutes, then grind to a fineness of less than 10 microns in a sand mill, then add items 8 and 9, stir at 600 rpm for 20 minutes, finally add items 10 to 15 in order, stir at 300 rpm for 10 minutes.

[0023] The diluent in each example of Table 1 is a mixture of butyl acetate:ethyl acetate:propylene glycol methyl ether acetate=50:35:15.

[0024] The method of using the above-mentioned low-reflectivity full-matt black paint is as follows: component A: curing agent: diluent are prepared in proportion, viscosity: 8.5 seconds (Yantian 2# cup), sprayed on the surface of the substrate, baked at 70℃~80℃ for 30 minutes, and baked at 80℃*120 minutes after it comes off the line to obtain samples of each embodiment.

[0025] The construction application of the samples of each embodiment is evaluated: the construction parameters are required to meet the needs of the customer's production site, the suitability of the production site, the compliance of the paint film appearance during construction, and the suitability of the baking and drying conditions of the production line.

[0026] 1. Appearance: The surface glossiness of the sample is less than 0.1°, which meets customer requirements.

[0027] 2. Adhesion test: Take 3 finished products or 3 150mm×100mm specimens, cut into 100 grids according to ISO 2409 standard, and quickly pull off the adhesive tape. If there is no peeling of the grids on the surface of the paint film and no obvious powdering, the adhesion is ≥ Grade 1.

[0028] 3. Chemical resistance test:

[0029] 2 square centimeters of 95% alcohol (room temperature, 10 minutes) were wiped on the sample. After the test, there was no abnormality such as fading, cracks, expansion, etc.

[0030] 2 square centimeters of interior cleaner were rubbed on the sample (room temperature, 2 hours). After the test, there was no abnormality such as fading, cracks, expansion, etc.

[0031] 4. High temperature storage test: The samples were stored and tested at a high temperature of 105°C for 300 hours. There was no obvious change in the appearance of the paint film, and the coating had no bubbling, shedding, cracking, etc. The adhesion was level 1.

[0032] 5. Low temperature storage test: The samples were stored and tested at a low temperature of -40℃ for 300 hours. There was no obvious change in the appearance of the paint film, and the coating had no bubbling, shedding, cracking, etc. The adhesion was level 1.

[0033] 6. High and low temperature impact test: Perform 50 cycles of high and low temperature alternating test (about 200 hours) under the following conditions. After the test, check that the sample has no abnormal appearance, and the coating has no blistering, shedding, cracking, etc. The adhesion is level 1.

[0034] (Test process description: temperature 25℃*50%RH humidity maintained for 30 minutes; temperature dropped from 25℃ to -40℃ for 30 minutes; maintained at -40℃ for 60 minutes; then heated to 65℃ for 30 minutes; then maintained at 65℃*50%RH for 60 minutes; cooled to 25℃*30%RH for 30 hours, which is one cycle.)

[0035] 7. High temperature and high humidity resistance test: The samples are stored in a high temperature and high humidity box at 65℃ / 80%RH*200 hours. There is no obvious change in the paint film, no bubbling, cracking, whitening and other abnormal phenomena, and the adhesion is level 1.

[0036] 8. Xenon lamp aging test (UV): Sample irradiation power: 0.55w / m2*340nm;

[0037] Under the experimental conditions of blackboard temperature of 38±3℃, box air temperature of 38±3℃, and relative humidity of 95±5%RH, run a 60-minute dark cycle, and spray water on the front and back sides at the same time; under the experimental conditions of blackboard temperature of 70±3℃, box air temperature of 47±3℃, and relative humidity of 95±5%RH, run a 40-minute light cycle: the alternating cycle of darkness and light runs for a total of 300 hours; the color change of the paint film before and after the test, the grayscale level is ≥4, there is no abnormal phenomenon such as bubbling, cracking, and falling off on the paint film surface, and the adhesion is level 1.

[0038] 9. Surface reflectivity: The light wave reflectivity of the sample surface is less than 1.0.

[0039] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0040] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

[0041] In addition, various embodiments of the present invention may be arbitrarily combined, and as long as they do not violate the concept of the present invention, they should also be regarded as the contents disclosed by the present invention.

Claims

1. A low reflectivity full matte black paint, characterized in that: It is a two-component system, including component A and component B in a mass ratio of 10:(7-11). The component A contains the following components in percentage by mass: 20-30% polycarbonate resin G3452, 10-15% hydroxy acrylic resin FS2451, 10-16% propylene glycol methyl ether acetate, 25-38% butyl ester, 3-6% dispersant, 2-5% high-pigment carbon black powder, 2-5% carbon nanotubes, 5-10% black elastic powder, 2-4% matting powder, 2-5% anti-settling agent, 0.3-0.8% leveling agent, 0.2-0.5% PU drying agent, 0.3-0.8% ultraviolet light absorber, and 0.2-0.5% ultraviolet light stabilizer; The B component includes 1-3 parts by weight of curing agent N3390 and 6-8 parts by weight of diluent.

2. The low reflectivity full matte black paint according to claim 1, characterized in that: The dispersant is S32500, the high-pigment carbon black powder is 5000, the carbon nanotube is TF210, the matting powder is OK520, the anti-settling agent is 4200-10, the leveling agent is BYK333, the PU drying agent is T-12, the ultraviolet light absorber is TINUVIN 1130, and the ultraviolet light stabilizer is INUVIN 292.

3. The method for using the low reflectivity full matte black paint according to claim 1, characterized in that: The diluent is a mixture of butyl acetate:ethyl acetate:propylene glycol methyl ether acetate=(45-55):(30-40):(10-20).

4. A method for preparing the low-reflectivity full-matt black paint according to any one of claims 1 to 3, characterized in that: The preparation method of the A component is as follows: polycarbonate resin, hydroxy acrylic resin, propylene glycol methyl ether acetate, a part of butyl ester and dispersant are added in order, dispersed and stirred at 300 rpm for 5 minutes, high-pigment carbon black powder and carbon nanotubes are added in turn, stirred at 500 rpm for 30 minutes, and then ground in a sand mill to a fineness of less than 10 microns, black elastic powder and matting powder are added, dispersed and stirred at 600 rpm for 20 minutes, and finally anti-settling agent, leveling agent, PU drying agent, remaining butyl ester, ultraviolet light absorber and ultraviolet light stabilizer are added in turn, and dispersed and stirred at 300 rpm for 10 minutes.

5. A method for using the low-reflectivity full-matt black paint according to any one of claims 1 to 3, characterized in that: Component A: curing agent: diluent = 10:1.5:6~8 oil ratio, viscosity: 8.5 seconds (Yantian 2# cup), spray on the surface of the substrate, bake at 70℃~80℃ for 30 minutes, and bake at 80℃*120 minutes after going offline.

6. A substrate, characterized in that The surface of the substrate is coated with the low-reflectivity full-matt black paint according to any one of claims 1 to 3, and the substrate comprises PC+PBT material.

7. The substrate according to claim 6, characterized in that The substrate is a light source cover of a vehicle-mounted head-up display system.

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