Optical thin film with high hardness, strong adhesive force and anti-wear function and preparation method thereof

Abstract

The invention discloses an optical thin film with high hardness, strong adhesive force and an anti-wear function and a preparation method thereof. The optical thin film comprises a substrate, a plurality of covering layers and a plurality of protective layers are arranged above the substrate, the covering layers and the protective layers are alternately arranged, and the uppermost layer of the optical thin film is the covering layer. The optical thin film is high in hardness, the problem that an outer-layer thin film is prone to being scratched is solved, meanwhile, the anti-reflection performance of thin film light rays is excellent, and the scratch-proof effect is good.

Description

Technical Field

[0001] This invention relates to the field of optical thin film preparation, and in particular to an optical thin film with high hardness, strong adhesion and wear resistance. Background Technology

[0002] Currently, smart terminals, especially mobile phones, tablets, laptops, projectors, instrument protective windows, and special lenses, often employ coating processes to improve product characteristics, ultimately creating a product with special optical functions (such as anti-reflection, beam splitting, and beam cutoff) and decorative effects. To address the scratches and wear caused by friction from dust particles, keys, and other hard objects in the environment during touch operation, the surface optical function or decorative coating must possess high hardness, scratch resistance, and wear resistance. To solve these problems, previous inventors disclosed a hard coating, an anti-reflective film, and an image display device. This hard coating, made from lipid compounds and organometallic catalysts, addresses the issue of easy scratching of the outer film. However, the addition of organometallic catalysts to this film structure affects light transmittance, and the scratch resistance effect remains unsatisfactory.

[0003] The above background information is provided only to aid in understanding the inventive concept and technical solution of this invention. It does not necessarily belong to the prior art of this patent application. In the absence of clear evidence that the above information was disclosed on the filing date of this patent application, the above background information should not be used to evaluate the novelty and inventiveness of this application. Summary of the Invention

[0004] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows:

[0005] An optical thin film with high hardness, strong adhesion and wear resistance includes a substrate; a plurality of cover layers and a plurality of protective layers are disposed on the substrate, the cover layers and protective layers are disposed alternately, and the uppermost layer of the optical thin film is a cover layer.

[0006] Preferably, the thickness of the substrate is greater than or equal to 5 μm and less than or equal to 1 mm.

[0007] Preferably, the substrate is one of silicon wafer, glass, ceramic, sapphire, polymer, or fused silica.

[0008] The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance includes the following steps:

[0009] 1) Dissolve cellulose, TEMPO and NaBr in water and stir to dissolve the cellulose. Add 5% NaClO solution dropwise to adjust the pH of the solution to 10. React at 25-30℃ for 3 hours to form a suspension.

[0010] 2) Centrifuge the formed suspension, wash the precipitate three times with 0.1M HCl, and dialyze to neutral; use sonication to prepare a 1wt% CNF suspension, and freeze-dry for later use;

[0011] 3) The obtained CNF was loaded into a reactor, supercritical CO2 was injected and kept for 1 h; perfluorooctyl iodide was injected, UV irradiation was turned on and the reaction was carried out for 2 h; CO2 was slowly released to atmospheric pressure, the product was washed 3 times with perfluorohexane and dried under vacuum at 60 °C to obtain the reactant.

[0012] 4) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the substrate to obtain a protective layer;

[0013] 5) Bi2Se3 nanoribbons and isopropanol were mixed and spin-coated onto the protective layer, and then annealed in an inert gas atmosphere to obtain the capping layer;

[0014] 6) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the cover layer to obtain a protective layer;

[0015] 7) Repeat steps 5) and 6) 4-5 times. The final top layer is the cover layer, which gives an optical film with high hardness, strong adhesion and wear resistance.

[0016] Preferably, in step 5), the inert gas is nitrogen, and the annealing temperature is 150°C for 30 minutes.

[0017] Preferably, in step 2), the suspension is centrifuged at 8000 rpm for 15 min; and the ultrasonic treatment is performed at 20 kHz for 30 min.

[0018] Preferably, in step 3), the supercritical CO2 injection temperature is 60°C and the pressure is 20 MPa; perfluorooctyl iodide (C8F) is injected. 17 I) 5 mL, UV irradiation intensity 50 mW / cm 2 .

[0019] Preferably, in step 4), the reactants are dispersed in supercritical CO2 at a weight percentage of 0.5 wt%, and the ultrasonic treatment frequency is 40 kHz for 30 min.

[0020] Preferably, the carrier gas for cold spraying is N2, the cold spraying pressure is 0.8MPa, the temperature is 25℃, the nozzle distance is 50mm, and the scanning speed is 10mm / s.

[0021] Preferably, the substrate is one of silicon wafer, glass, ceramic, sapphire, polymer, or fused silica.

[0022] Preferably, in step 4), pressure is applied immediately after spraying using a SiO2 nano-molding, with a groove size of 100 nm, a pressure of 5 MPa, and a time of 30 s. Applying pressure using a SiO2 nano-molding can enhance the hardness of optical films that possess high hardness, strong adhesion, and wear resistance.

[0023] Preferably, in step (5), Bi2Se3 nanoribbons are mixed with isopropanol at a mass ratio of 1:(100-200).

[0024] Preferably, in step (5), Bi2Se3 nanoribbons are mixed with isopropanol at a mass ratio of 1:200.

[0025] Preferably, the thickness of the Bi2Se3 nanoribbons is 20-50 nm.

[0026] Preferably, in step 1), the mass ratio of cellulose:TEMPO:NaBr is 6.17:0.12:1.23.

[0027] Compared with the prior art, the advantages and beneficial effects of the present invention are as follows:

[0028] The optical film of this invention has high hardness, which solves the problem of easy scratching of the outer film. At the same time, the film has excellent light transmittance and good scratch resistance. Detailed Implementation

[0029] The following embodiments can help those skilled in the art to more fully understand the present invention, but should not be construed as limiting the present invention in any way.

[0030] Example

[0031] An optical thin film with high hardness, strong adhesion and wear resistance includes a substrate; a plurality of cover layers and a plurality of protective layers are disposed on the substrate, the cover layers and protective layers are disposed alternately, and the uppermost layer of the optical thin film is a cover layer.

[0032] In one embodiment of the present invention, the thickness of the substrate is greater than or equal to 5 μm and less than or equal to 1 mm.

[0033] In one embodiment of the present invention, the substrate is one of silicon wafer, glass, ceramic, sapphire, polymer, or fused silica.

[0034] The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance includes the following steps:

[0035] 1) Dissolve cellulose, TEMPO and NaBr in water and stir to dissolve the cellulose. Add 5% NaClO solution dropwise to adjust the pH of the solution to 10. React at 25-30℃ for 3 hours to form a suspension.

[0036] 2) Centrifuge the formed suspension, wash the precipitate three times with 0.1M HCl, and dialyze to neutral; use sonication to prepare a 1wt% CNF suspension, and freeze-dry for later use;

[0037] 3) The obtained CNF was loaded into a reactor, supercritical CO2 was injected and kept for 1 h; perfluorooctyl iodide was injected, UV irradiation was turned on and the reaction was carried out for 2 h; CO2 was slowly released to atmospheric pressure, the product was washed 3 times with perfluorohexane and dried under vacuum at 60 °C to obtain the reactant.

[0038] 4) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the substrate to obtain a protective layer;

[0039] 5) Bi2Se3 nanoribbons and isopropanol were mixed and spin-coated onto the protective layer, and then annealed in an inert gas atmosphere to obtain the capping layer;

[0040] 6) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the cover layer to obtain a protective layer;

[0041] 7) Repeat steps 5) and 6) 4-5 times. The final top layer is the cover layer, which gives an optical film with high hardness, strong adhesion and wear resistance.

[0042] In one embodiment of the present invention, in step (1), the molar ratio of cellulose to TEMPO and NaBr is 1:(0.02-0.05):(0.1-0.5).

[0043] In one embodiment of the present invention, in step (1), the molar ratio of cellulose to TEMPO and NaBr is 1:0.03:0.2.

[0044] In one embodiment of the present invention, the inert gas in step 5) is nitrogen, and the annealing temperature is 150°C and the time is 30 minutes.

[0045] In one embodiment of the present invention, in step 2), the suspension is centrifuged at a speed of 8000 rpm for 15 min; the ultrasonic treatment is performed at a frequency of 20 kHz for 30 min.

[0046] In one embodiment of the present invention, in step 3), the supercritical CO2 injection temperature is 60°C and the pressure is 20 MPa; perfluorooctyl iodide (C8F) is injected. 17 I) 5 mL, UV irradiation intensity 50 mW / cm 2 .

[0047] In one embodiment of the present invention, in step 4), the reactants are dispersed in supercritical CO2 at a weight percentage of 0.5 wt%, and the ultrasonic treatment frequency is 40 kHz for 30 min.

[0048] In one embodiment of the present invention, the carrier gas for cold spraying is N2, the cold spraying pressure is 0.8MPa, the temperature is 25°C, the nozzle distance is 50mm, and the scanning speed is 10mm / s.

[0049] In one embodiment of the present invention, the substrate is one of silicon wafer, glass, ceramic, sapphire, polymer, or fused silica.

[0050] In one embodiment of the present invention, in step 4), immediately after spraying, pressure is applied using a SiO2 nano-molding tool with a groove size of 100 nm, a pressure of 5 MPa, and a time of 30 s. Applying pressure using a SiO2 nano-molding tool can enhance the hardness of the optical thin film, which possesses high hardness, strong adhesion, and wear resistance.

[0051] In one embodiment of the present invention, in step (5), Bi2Se3 nanoribbons are mixed with isopropanol at a mass ratio of 1:(100-200).

[0052] In one embodiment of the present invention, in step (3), the molar ratio of perfluorooctyl iodide to cellulose nanofibers is 2.5:1.

[0053] In one embodiment of the present invention, the thickness of the Bi2Se3 nanoribbon is 20-50 nm.

[0054] In one embodiment of the present invention, the thickness of the Bi2Se3 nanoribbon is 50 nm.

[0055] In one embodiment of the present invention, the thickness of the Bi2Se3 nanoribbon is 30 nm.

[0056] Example 1

[0057] The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance includes the following steps:

[0058] 1) Dissolve cellulose, TEMPO and NaBr in water and stir to dissolve the cellulose. Add 5% NaClO solution dropwise to adjust the pH of the solution to 10. React at 25-30℃ for 3 hours to form a suspension.

[0059] 2) Centrifuge the formed suspension, wash the precipitate three times with 0.1M HCl, and dialyze to neutral; use sonication to prepare a 1wt% cellulose nanofiber suspension, and freeze-dry for later use;

[0060] 3) The obtained cellulose nanofibers were loaded into a reaction vessel, supercritical CO2 was injected and maintained for 1 h; perfluorooctyl iodide was injected, UV irradiation was turned on and the reaction was carried out for 2 h; CO2 was slowly released to atmospheric pressure, the product was washed 3 times with perfluorohexane and dried under vacuum at 60 °C to obtain the reactant.

[0061] 4) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the substrate to obtain a protective layer;

[0062] 5) Bi2Se3 nanoribbons and isopropanol were mixed and spin-coated onto the protective layer, and then annealed in an inert gas atmosphere to obtain the capping layer;

[0063] 6) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the cover layer to obtain a protective layer;

[0064] 7) Repeat steps 5) and 6) 4-5 times. The final top layer is the cover layer, which gives an optical film with high hardness, strong adhesion and wear resistance.

[0065] Furthermore, in step 5), the inert gas is nitrogen, and the annealing temperature is 150°C for 30 minutes.

[0066] Furthermore, in step 2), the formed suspension is centrifuged at 8000 rpm for 15 min; and the ultrasonic treatment is performed at 20 kHz for 30 min.

[0067] Furthermore, in step 3), the supercritical CO2 injection temperature is 60°C and the pressure is 20 MPa; perfluorooctyl iodide (C8F) is injected. 17 I) 5 mL, UV irradiation intensity 50 mW / cm 2 .

[0068] Furthermore, in step 4), the reactants are dispersed in supercritical CO2 at a weight percentage of 0.5 wt%, and the ultrasonic treatment is performed at a frequency of 40 kHz for 30 min.

[0069] Furthermore, the carrier gas for cold spraying is N2, the cold spraying pressure is 0.8MPa, the temperature is 25℃, the nozzle distance is 50mm, and the scanning speed is 10mm / s.

[0070] Furthermore, the substrate is one of silicon wafers, glass, ceramics, sapphire, polymers, or fused silica.

[0071] Furthermore, in step 4), immediately after spraying, pressure is applied using a SiO2 nano-molding technique with a groove size of 100 nm, a pressure of 5 MPa, and a time of 30 seconds. This SiO2 nano-molding technique enhances the hardness of the optical film, which possesses high hardness, strong adhesion, and wear resistance.

[0072] Furthermore, the thickness of the Bi2Se3 nanoribbons is 50 nm.

[0073] Example 2

[0074] The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance includes the following steps:

[0075] 1) Dissolve cellulose, TEMPO and NaBr in water and stir to dissolve the cellulose. Add 5% NaClO solution dropwise to adjust the pH of the solution to 10. React at 25-30℃ for 3 hours to form a suspension.

[0076] 2) Centrifuge the formed suspension, wash the precipitate three times with 0.1M HCl, and dialyze to neutral; use sonication to prepare a 1wt% CNF suspension, and freeze-dry for later use;

[0077] 3) The obtained CNF was loaded into a reactor, supercritical CO2 was injected and kept for 1 h; perfluorooctyl iodide was injected, UV irradiation was turned on and the reaction was carried out for 2 h; CO2 was slowly released to atmospheric pressure, the product was washed 3 times with perfluorohexane and dried under vacuum at 60 °C to obtain the reactant.

[0078] 4) Disperse the reactants in supercritical CO2 and perform ultrasonic treatment. Heat the substrate to 60-78℃ and cold spray the reactants onto the substrate to obtain a protective layer. Immediately after spraying, apply pressure with a SiO2 nano-molding mold. The groove is 100nm, the pressure is 5MPa, and the time is 30s.

[0079] 5) Bi2Se3 nanoribbons and isopropanol were mixed and spin-coated onto the protective layer, and then annealed in an inert gas atmosphere to obtain the capping layer;

[0080] 6) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the cover layer to obtain a protective layer;

[0081] 7) Repeat steps 5) and 6) 4-5 times. The final top layer is the cover layer, which gives an optical film with high hardness, strong adhesion and wear resistance.

[0082] Furthermore, in step 5), the inert gas is nitrogen, and the annealing temperature is 150°C for 30 minutes.

[0083] Furthermore, in step 2), the formed suspension is centrifuged at 8000 rpm for 15 min; and the ultrasonic treatment is performed at 20 kHz for 30 min.

[0084] Furthermore, in step 3), the supercritical CO2 injection temperature is 60°C and the pressure is 20 MPa; perfluorooctyl iodide (C8F) is injected. 17 I) 5 mL, UV irradiation intensity 50 mW / cm 2 .

[0085] Furthermore, in step 4), the reactants are dispersed in supercritical CO2 at a weight percentage of 0.5 wt%, and the ultrasonic treatment is performed at a frequency of 40 kHz for 30 min.

[0086] Furthermore, the carrier gas for cold spraying is N2, the cold spraying pressure is 0.8MPa, the temperature is 25℃, the nozzle distance is 50mm, and the scanning speed is 10mm / s.

[0087] Furthermore, the substrate is one of silicon wafers, glass, ceramics, sapphire, polymers, or fused silica.

[0088] Furthermore, in step 4), the hardness of the optical thin film, which has high hardness, strong adhesion and wear resistance, can be enhanced by applying pressure through SiO2 nano-molding.

[0089] Furthermore, the thickness of the Bi2Se3 nanoribbons is 30 nm.

[0090] Example 3

[0091] The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance includes the following steps:

[0092] 1) Dissolve cellulose, TEMPO and NaBr in water and stir to dissolve the cellulose. Add 5% NaClO solution dropwise to adjust the pH of the solution to 10. React at 25-30℃ for 3 hours to form a suspension.

[0093] 2) Centrifuge the formed suspension, wash the precipitate three times with 0.1M HCl, and dialyze to neutral; use sonication to prepare a 1wt% CNF suspension, and freeze-dry for later use;

[0094] 3) The obtained CNF was loaded into a reactor, supercritical CO2 was injected and kept for 1 h; perfluorooctyl iodide was injected, UV irradiation was turned on and the reaction was carried out for 2 h; CO2 was slowly released to atmospheric pressure, the product was washed 3 times with perfluorohexane and dried under vacuum at 60 °C to obtain the reactant.

[0095] 4) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the substrate to obtain a protective layer;

[0096] 5) Bi2Se3 nanoribbons and isopropanol were mixed and spin-coated onto the protective layer, and then annealed in an inert gas atmosphere to obtain the capping layer;

[0097] 6) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the cover layer to obtain a protective layer;

[0098] 7) Repeat steps 5) and 6) 4-5 times. The final top layer is the cover layer, which gives an optical film with high hardness, strong adhesion and wear resistance.

[0099] Furthermore, in step 5), the inert gas is nitrogen, and the annealing temperature is 150°C for 30 minutes.

[0100] Furthermore, in step 2), the formed suspension is centrifuged at 8000 rpm for 15 min; and the ultrasonic treatment is performed at 20 kHz for 30 min.

[0101] Furthermore, in step 3), the supercritical CO2 injection temperature is 60°C and the pressure is 20 MPa; perfluorooctyl iodide (C8F) is injected. 17 I) 5 mL, UV irradiation intensity 50 mW / cm 2 .

[0102] Furthermore, in step 4), the reactants are dispersed in supercritical CO2 at a weight percentage of 0.5 wt%, and the ultrasonic treatment is performed at a frequency of 40 kHz for 30 min.

[0103] Furthermore, the carrier gas for cold spraying is N2, the cold spraying pressure is 0.8MPa, the temperature is 25℃, the nozzle distance is 50mm, and the scanning speed is 10mm / s.

[0104] Furthermore, the substrate is one of silicon wafers, glass, ceramics, sapphire, polymers, or fused silica.

[0105] Furthermore, the thickness of the Bi2Se3 nanoribbons is 60 nm.

[0106] Experimental Example

[0107] Table 1 shows the performance test results of the optical films prepared in Examples 1-3, which have high hardness, strong adhesion, and wear resistance, under the same conditions.

[0108] Example Hardness (nanoindentation (ISO 14577)) Light transmittance Environmental stability UV aging (QUV test, 1000h) Adhesion cross-cut test (ASTM D3359) Example 1 11GPa 92 ΔYI<1.5(ASTM G154) 5B Example 2 12 GPa 91 ΔYI<1.5(ASTM G154) 5B Example 3 9 GPa 90 ΔYI<1.5(ASTM G154) 4B

[0109] Table 1

[0110] As can be seen from the data in Table 1, in step 4), the SiO2 nano-molding is applied immediately after spraying. Applying pressure with the SiO2 nano-molding can enhance the performance of optical films with high hardness, strong adhesion and wear resistance.

[0111] The present invention has been described in detail above. However, modifications or improvements can be made to it, which will be obvious to those skilled in the art. Therefore, any modifications or improvements that do not depart from the spirit of the present invention are within the scope of protection of the present invention.

Claims

1. An optical thin film with high hardness, strong adhesion, and wear resistance, characterized in that: It includes a substrate; several cover layers and several protective layers are disposed on the substrate, with the cover layers and protective layers being disposed alternately, and the topmost layer of the optical film is the cover layer.

2. The optical thin film with high hardness, strong adhesion, and wear resistance as described in claim 1, characterized in that: The thickness of the substrate is greater than or equal to 5 μm and less than or equal to 1 mm.

3. The optical thin film with high hardness, strong adhesion, and wear resistance as described in claim 1, characterized in that: The substrate can be one of silicon wafer, glass, ceramic, sapphire, polymer, or fused silica.

4. A method for preparing an optical thin film with high hardness, strong adhesion, and wear resistance as described in any one of claims 1-3, characterized in that: Includes the following steps: 1) Dissolve cellulose, TEMPO and NaBr in water and stir to dissolve the cellulose. Add 5% NaClO solution dropwise to adjust the pH of the solution to 10. React at 25-30℃ for 3 hours to form a suspension. 2) Centrifuge the resulting suspension, wash the precipitate three times with 0.1M HCl, and dialyze until neutral; A 1wt% CNF suspension was prepared by ultrasonic treatment and then freeze-dried for later use. 3) The obtained CNF was loaded into a reactor, supercritical CO2 was injected and kept for 1 h; perfluorooctyl iodide was injected, UV irradiation was turned on and the reaction was carried out for 2 h; CO2 was slowly released to atmospheric pressure, the product was washed 3 times with perfluorohexane and dried under vacuum at 60 °C to obtain the reactant. 4) Disperse the reactants in supercritical CO2 and perform ultrasonic treatment. Heat the substrate to 60-78℃ and cold spray the reactants onto the substrate to obtain a protective layer. Immediately after spraying, apply pressure with a SiO2 nano-molding mold. The groove is 100nm, the pressure is 5MPa, and the time is 30s. 5) Bi2Se3 nanoribbons and isopropanol were mixed and spin-coated onto the protective layer, and then annealed in an inert gas atmosphere to obtain the capping layer; 6) Disperse the reactants in supercritical CO2, perform ultrasonic treatment, heat the substrate to 60-78℃, and cold spray the reactants onto the cover layer to obtain a protective layer; 7) Repeat steps 5) and 6) 4-5 times. The final top layer is the cover layer, which gives an optical film with high hardness, strong adhesion and wear resistance.

5. The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance as described in claim 4, characterized in that: In step 2), the resulting suspension is centrifuged at 8000 rpm for 15 min; the ultrasonic treatment is performed at 20 kHz for 30 min.

6. The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance as described in claim 4, characterized in that: In step 3), the supercritical CO2 injection temperature is 60℃ and the pressure is 20MPa; 5mL of perfluorooctyl iodide is injected, and the UV irradiation intensity is 50mW / cm². 2 .

7. The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance as described in claim 4, characterized in that: In step 4), immediately after spraying, apply pressure using a SiO2 nano-molding tool with a groove size of 100 nm, a pressure of 5 MPa, and a time of 30 s.

8. The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance as described in claim 4, characterized in that: The thickness of Bi2Se3 nanoribbons is 20-50 nm.

9. The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance as described in claim 4, characterized in that: In step 4), the reactants are dispersed in supercritical CO2 at a weight percentage of 0.5 wt%, and the ultrasonic treatment is performed at a frequency of 40 kHz for 30 min.

10. The method for preparing the optical thin film with high hardness, strong adhesion and wear resistance as described in claim 4, characterized in that: In step 5), the inert gas is nitrogen, and the annealing temperature is 150°C for 30 minutes.