Method for improving stability of quantum dot optical film
The quantum dot optical film was prepared by mixing the silanized BN nanosheets with the quantum dot solution, which solved the problem of optical performance degradation caused by hydrolysis by silane coupling agent, and achieved the improvement of the stability and water oxygen resistance of the quantum dot optical film.
Patent Information
- Application Number
- CN202510288451.8
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-03-12
- Publication Date
- 2025-07-04
AI Technical Summary
In the prior art, when improving the water oxygen resistance of quantum dot optical films, the hydrolysis by-product of the silane coupling agent leads to a degradation of optical performance, making it difficult to balance the improvement between the two and maintain optical performance.
The BN nanosheets that were silanized were mixed with the quantum dot solution, and the quantum dot optical film was prepared by roll-on coating. The SiO2 shell was formed by silanized treatment of the BN nanosheets to isolate water and oxygen, and the optical properties were kept unchanged.
Without affecting optical performance, the water oxygen resistance and stability of the quantum dot optical film are significantly improved, extending the use time and maintaining the brightness without attenuation.
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Abstract
Description
Technical Field
[0001] The present invention belongs to the technical field of light-emitting devices, and particularly relates to a method for improving the stability of a quantum dot optical film. Background Art
[0002] The existence of the quantum confinement effect endows quantum dots with the property of tunable emission wavelength for a given chemical composition / structure, which is the first key advantage of quantum dots for display applications. The second key advantage is that they have a single-crystalline lattice stabilized by thousands to millions of thermodynamically equivalent bonds, which makes their emission color extremely pure (narrow emission peaks). The third key advantage is that they have good stability under strong light irradiation and heating. These advantages have led to a rapid increase in the market share of quantum dot optical films in recent years.
[0003] Currently, coating quantum dots with SiO2 can improve their resistance to water and oxygen. The main mechanism of SiO2 coating is as follows: through ligand exchange, a silane coupling agent is grafted onto the surface of the quantum dots. As the reaction proceeds, the silane coupling agent will further hydrolyze to form a SiO2 shell layer coating on the surface of the quantum dots, thereby improving the water and oxygen resistance of the quantum dots. However, the by-products of the hydrolysis of the silane coupling agent are often water or alcohol substances, and highly polar solvents often cause a significant decrease in the optical properties of the quantum dots.
[0004] Therefore, it is urgent to explore a solution that balances the two, which can not only improve the water and oxygen stability of the quantum dot optical film but also prevent a significant decrease in the optical properties of the quantum dot optical film. Summary of the Invention
[0005] Technical Problem to be Solved: In view of the above technical problems, the present invention provides a method for improving the stability of a quantum dot optical film. The method is simple and effective, with mild reactions and high repeatability. It can effectively improve the water and oxygen resistance of the quantum dot optical film on the premise of ensuring that the optical properties of the quantum dot optical film do not decrease significantly.
[0006] Technical Solution: A method for improving the stability of a quantum dot optical film, comprising the following steps: Step 1: Subject BN nanosheets to silanization treatment with a silane coupling agent, and then obtain silanized BN powder through centrifugation and drying; Step 2: Add the silanized BN powder and the quantum dot solution to an acrylic resin glue and stir; Step 3: Obtain the quantum dot optical film through roll-to-roll coating.
[0007] Preferably, in the step one, the silane coupling agent is selected from one or more of: tetraethoxysilane, tetrapropoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, diphenyldihydroxysilane, (3-mercaptopropyl)trimethoxysilane.
[0008] Preferably, in the step one, the dosage ratio of BN nanosheets to the silane coupling agent is 1 g : (5 - 30) mL.
[0009] Preferably, in the step one, the BN nanosheets are first dissolved in ethanol and ultrasonically mixed before the silanization treatment.
[0010] Furthermore, the dosage ratio of BN nanosheets to ethanol is 1 g : (100 - 150) mL, and the ultrasonic time is 5 - 30 min.
[0011] Preferably, in the step one, the silanization treatment conditions are: stirring in a sealed environment, the stirring speed is 300 - 500 r / min, and the stirring time is 12 - 48 h.
[0012] Preferably, in the step one, the centrifugation conditions are: the rotation speed is 12000 - 15000 r / min, and the time is 5 - 15 min.
[0013] Preferably, in the step one, the drying conditions are: vacuum drying, the temperature is 60 - 80 °C, and the time is 1 - 2 h.
[0014] Preferably, in the step two, the mass of the silanized BN powder is 0.25% - 5% of the mass of the quantum dots.
[0015] Preferably, in the step two, the stirring speed is 600 - 2500 r / min, and the time is 30 - 50 min.
[0016] Beneficial effects: The method of the present invention is simple and effective, the reaction is mild, and the repetition rate is high. It can effectively improve the water and oxygen resistance of the quantum dot optical film on the premise of ensuring that the optical performance of the quantum dot optical film does not decrease significantly.
[0017] The improved quantum dot optical film prepared by the present invention has two performance advantages: (1) The stability is improved, effectively extending the service time of the quantum dot optical film; (2) The brightness of the improved quantum dot optical film does not decay, ensuring the optical performance of the product. Specific embodiments
[0018] The present invention will be further described below in conjunction with specific embodiments. Example 1
[0019] A method for improving the stability of quantum dot optical films, comprising the following steps: Step 1: Dissolve 20 mg of BN nanosheets in 5 mL of ethanol, ultrasonicate for 5 min. After complete dissolution, add 5 mL of tetraethoxysilane (TEOS) as a silane coupling agent, stir in a sealed environment at a stirring speed of 250 r / min for 0.5 h. After the silanization treatment, centrifuge and dry to obtain silanized BN powder. Among them, the centrifugation conditions are: rotation speed 4000 r / min, time 2.0 min; the drying conditions are: vacuum drying oven, temperature 50 °C, time 2.0 h.
[0020] Step 2: Take 18.3 g of green light quantum dot solution (quantum dot mass ratio is 10%) and 6.9 g of red light quantum dot solution (quantum dot mass ratio is 10%), and 0.126 g (0.5% of the total mass of the quantum dot solution) of tetraethoxysilane (TEOS)-modified BN powder into the acrylic resin glue, and stir at 2000 r / min at room temperature for 35 min.
[0021] Step 3: Prepare a quantum dot optical film by high-precision roll-to-roll coating.
[0022] The optical result detection shows that the color dots of the quantum dot optical film are basically unchanged, and the stability is improved by 4.1%. Example 2
[0023] A method for improving the stability of quantum dot optical films, comprising the following steps: Step 1: Dissolve 30 mg of BN nanosheets in 10 mL of ethanol, ultrasonicate for 5 min. After complete dissolution, add 5 mL of (3-mercaptopropyl)trimethoxysilane (MPS) as a silane coupling agent, stir in a sealed environment at a stirring speed of 300 r / min for 1.0 h. After the silanization treatment, centrifuge and dry to obtain silanized BN powder. Among them, the centrifugation conditions are: rotation speed 4000 r / min, time 2.0 min; the drying conditions are: vacuum drying oven, temperature 50 °C, time 2.0 h.
[0024] Step 2: Take 18.3 g of green light quantum dot solution (quantum dot mass ratio is 10%) and 6.9 g of red light quantum dot solution (quantum dot mass ratio is 10%), and 1.26 g (5% of the quantum dot solution mass) of (3-mercaptopropyl)trimethoxysilane (MPS)-modified BN powder into the acrylic resin glue, and stir at 2500 r / min at room temperature for 35 min.
[0025] Step 3: Prepare a quantum dot optical film by high-precision roll-to-roll coating.
[0026] The optical result shows that the color points of the quantum dot optical film are basically unchanged, and the stability is improved by 2.9%. Example 3
[0027] A method for improving the stability of a quantum dot optical film, comprising the following steps: Step 1: Dissolve 25 mg of BN nanosheets in 15 mL of ethanol, ultrasonicate for 10 min. After dissolution, add 2.0 g of diphenyldihydroxysilane (DPSD) as a silane coupling agent, stir in a sealed environment at a stirring speed of 300 r / min for 1.5 h. After the silylation treatment, the silylated BN powder is obtained by centrifugation and drying. Among them, the centrifugation conditions are: rotation speed 4000 r / min, time 2.0 min; the drying conditions are: vacuum drying oven, temperature 50 °C, time 2.0 h.
[0028] Step 2: Take 18.3 g of green quantum dot solution (quantum dot mass ratio is 10%) and 6.9 g of red quantum dot solution (quantum dot mass ratio is 10%), and 0.252 g (1% of the quantum dot mass) of diphenyldihydroxysilane (DPSD)-modified BN powder into the acrylic resin glue, and stir at 1500 r / min for 40 min at room temperature.
[0029] Step 3: Prepare the quantum dot optical film by high-precision roll-to-roll coating.
[0030] The optical result shows that the color points of the quantum dot optical film are basically unchanged, and the stability is improved by 0.3%.
[0031] The present invention aims at the contradiction points of the prior art: the silylation of quantum dots helps to improve the water and oxygen resistance of quantum dots, while the by-products of the hydrolysis of the silane coupling agent will cause loss of the optical properties of quantum dots. Accordingly, the above technical problems are solved by directly preparing a quantum dot optical film by adding silylated BN powder.
[0032] Taking the non-addition of BN powder and the addition of unmodified BN powder as a comparison, the optical data of the prepared quantum dot optical film and the reliability data at 85 °C and 85% relative humidity (RH) for 500 hours are as follows:
[0033] The presence of BN nanosheets can retain the excellent fluorescence properties of quantum dots and enhance the optical stability of quantum dots. After the prepared quantum dot optical film is penetrated by water and oxygen, the silane coupling agent quickly forms a SiO2 shell layer when encountering water molecules, effectively isolating the further influence of water molecules on quantum dots. The presence of BN nanosheets effectively enhances the ability of the optical film to resist oxygen atom erosion. The combination of the two effectively improves the stability of the quantum dot optical film. Different from directly adding a liquid silane coupling agent, the influence of the dried silanized BN powder on the optical properties of quantum dots is reduced.
[0034] In summary, the addition of silanized BN powder effectively improves the stability of the quantum dot optical film without affecting the optical properties of the optical film.
Claims
1. A method for improving the stability of a quantum dot optical film, characterized in that, It includes the following steps: Step 1: Silanize BN nanosheets with a silane coupling agent, and then obtain silanized BN powder through centrifugation and drying; Step 2: Add the silanized BN powder and the quantum dot solution to an acrylic resin glue and stir; Step 3: Prepare a quantum dot optical film by roll-to-roll coating.
2. The method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 1, the silane coupling agent is selected from one or more of: tetraethoxysilane, tetrapropoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltriethoxysilane, γ-aminopropylmethyldimethoxysilane, γ-glycidoxypropyltrimethoxysilane, diphenyldihydroxysilane, (3-mercaptopropyl)trimethoxysilane.
3. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 1, the dosage ratio of BN nanosheets to the silane coupling agent is 1 g : (5~30) mL.
4. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 1, the BN nanosheets are first dissolved in ethanol and ultrasonically mixed before silanization treatment.
5. The method for improving the stability of a quantum dot optical film according to claim 4, wherein The dosage ratio of BN nanosheets to ethanol is 1 g : (100~150) mL, and the ultrasonic time is 5~30 min.
6. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 1, the silanization treatment conditions are: stirring in a sealed environment, the stirring speed is 300~500 r / min, and the stirring time is 12~48 h.
7. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 1, the centrifugation conditions are: the rotation speed is 12000~15000 r / min, and the time is 5~15 min.
8. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 1, the drying conditions are: vacuum drying, the temperature is 60~80°C, and the time is 1~2 h.
9. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 2, the mass of the silanized BN powder is 0.25%~5% of the mass of the quantum dots.
10. A method for improving the stability of a quantum dot optical film according to claim 1, characterized in that, In the said Step 2, the stirring speed is 600~2500 r / min, and the time is 30~50 min.