Hydrophobic optical lens and preparation method thereof

Abstract

The invention relates to the technical field of coating, in particular to a hydrophobic optical lens and a preparation method thereof.The surface of the optical lens is coated with an antireflection film, and a substrate is prepared; the preparation method comprises the following steps: mixing FDTS and ethanol, uniformly stirring, and filtering to obtain a transparent FDTS ethanol solution; dropwise adding the FFDS ethanol solution to the center of the surface of the substrate, uniformly spreading the FFDS ethanol solution to the surface of the substrate by using a spin coater, and aging to form a stable hydrophobic membrane solution on the surface of the substrate; and transferring the substrate with the hydrophobic membrane solution into a drying oven for drying and curing, and forming a hydrophobic membrane on the surface of the substrate to prepare the hydrophobic optical lens. The preparation process is simple and easy to control, the quality of the film layer is easy to guarantee, the average transmittance is low, the water drop angle is 105-115 degrees, the performance such as friction resistance and temperature impact resistance is excellent, and the comprehensive performance such as hydrophobic performance, transmittance, firmness and reliability is good.

Description

Technical Field

[0001] This invention relates to the field of coating technology, specifically to a hydrophobic optical lens and its preparation method. Background Technology

[0002] To prevent fogging and glare on glass, optical glass is coated with an anti-reflective film to improve transmittance. At the same time, a smooth, dense, and transparent silicone hydrophobic film is coated to make the light emitted by the optical glass more uniform and softer. The hydrophobic film has important characteristics such as waterproofing, anti-fogging, anti-pollution, anti-corrosion, anti-adhesion, anti-oxidation, self-cleaning, and prevention of current conduction. It has extremely wide application prospects in many fields such as scientific research, production, and daily life.

[0003] Currently, the main methods for preparing transparent hydrophobic thin films include the sol-gel method, chemical vapor deposition (CVD), and physical vapor deposition (PVD). The methods most commonly used in glass applications both domestically and internationally are:

[0004] Physical vapor deposition (PVD) mainly evaporates fluorine-containing organic polymers, causing these organic substances to evaporate onto the surface of the object, thus making the object hydrophobic. However, the hydrophobic layer of this method is relatively soft and has poor resistance to ultraviolet aging, making it unsuitable for long-term outdoor use.

[0005] Chemical vapor deposition (CVD) mainly uses gaseous organosilanes (perfluorododecyltrichlorosilane FDTS) as raw materials. The hydrophobic organosilanes are deposited onto the substrate surface through plasma discharge, thereby giving the substrate hydrophobic properties. However, this method has high equipment costs and complex exhaust gas treatment systems, which is not conducive to its widespread application.

[0006] Sol-gel method: This is a relatively inexpensive method for depositing hydrophobic films, but the process is complex and difficult to control. Summary of the Invention

[0007] The purpose of this invention is to provide a hydrophobic optical lens with a simple manufacturing process and good overall performance, and the same method thereof.

[0008] To achieve the above objectives, the present invention provides the following technical solution:

[0009] This invention proposes a method for preparing a hydrophobic optical lens, comprising the following steps:

[0010] (1) A layer of antireflective coating is deposited on the surface of an optical lens to obtain a substrate;

[0011] (2) Mix FDTS and ethanol, stir well, filter, and obtain a transparent FDTS ethanol solution;

[0012] (3) Take an FDTS ethanol solution and drop it onto the center of the substrate surface. Use a spin coater to evenly spread the FDTS ethanol solution onto the substrate surface and let it age to form a stable hydrophobic film solution on the substrate surface.

[0013] (4) The substrate with the hydrophobic film solution is transferred to an oven to dry and cure, forming a hydrophobic film on the surface of the substrate, thus obtaining a hydrophobic optical lens.

[0014] Furthermore, the concentration of the FDTS ethanol solution in step (2) is 0.5% w / w.

[0015] Furthermore, the rotation speed of the spin coater in step (3) is 3000-3500 r / min.

[0016] Furthermore, the water droplet angle of the hydrophobic film solution on the substrate surface in step (3) is 105-115°.

[0017] Furthermore, the aging time in step (3) is 30 minutes.

[0018] Furthermore, the drying and curing temperature in step (4) is 180°C and the time is 3 hours.

[0019] Furthermore, the thickness of the hydrophobic film in step (4) is 4-6 nm.

[0020] The present invention also includes hydrophobic optical lenses prepared by any of the preparation methods described above.

[0021] Furthermore, it includes an optical lens, on which an anti-reflective coating and a hydrophobic coating are sequentially disposed.

[0022] Compared with existing technologies, the preparation process of this invention is simple and easy to control, and the quality of the film layer is easy to guarantee. The hydrophobic optical lens obtained has an average transmittance reduction of less than 0.2% in the range of 400-700nm, a water droplet angle of 105-115°, and excellent resistance to friction and temperature shock. It has good comprehensive performance in terms of hydrophobicity, transmittance, adhesion, and reliability. It solves the problems of poor adhesion in the original physical vapor deposition method and high equipment investment in the chemical vapor deposition method. It meets the product use requirements, improves product quality, and has great application value. Attached Figure Description

[0023] Figure 1 The droplet angle test diagram shows the test results for optical lenses and hydrophobic optical lenses.

[0024] Figure 2 This patent describes an atomic force microscope (AFM) mounted on optical glass coated with a hydrophobic film.

[0025] Figure 3 This is a profilometer scan image. Detailed Implementation

[0026] The technical solution of the present invention will be further described below with reference to specific embodiments. It should be understood that the following embodiments are merely illustrative and explanatory of the present invention and should not be construed as limiting the scope of protection of the present invention. All technologies implemented based on the above content of the present invention are covered within the scope of protection intended by the present invention.

[0027] Example 1

[0028] Prepare hydrophobic optical lenses using the following steps:

[0029] Step 1) On the optical lens (water droplet angle, such as...) Figure 1 As shown, an antireflective coating is deposited on the surface (<90°) to obtain the substrate (a conventional technique, which will not be described in detail).

[0030] Step 2) Mix perfluorododecyltrichlorosilane and ethanol, stir well, filter out the suspended matter with a filter to obtain a transparent FDTS ethanol solution with a concentration of 0.5% w / w.

[0031] Step 3) Use a plastic dropper to draw up FDTS ethanol solution and drop it onto the center area of ​​the substrate surface. Use a spin coater at 3000-3500 rpm to evenly spread the FDTS ethanol onto the substrate surface. Let it age at room temperature for 30 minutes to form a stable, transparent, hydrophobic film solution with a water droplet angle of 105-115° on the substrate surface. Figure 1 As shown, a hydrophobic optical lens was prepared.

[0032] It is worth mentioning that, in this step, the rotation speed of the spin coater, whether it is 3000 r / min, 3100, 3250 r / min, 3400 r / min, 3500 r / min, etc., as long as it is within the range of 3000-3500 r / min, will not affect the final hydrophobic optical lens to meet the test results mentioned below.

[0033] Step 4) Transfer the substrate with the hydrophobic film solution to an oven and dry it at 180°C for 3 hours to cure it, forming a hydrophobic film with a thickness of 4-6 nm on the substrate surface, thus obtaining a hydrophobic optical lens.

[0034] The test results of the prepared hydrophobic optical lens are as follows:

[0035] ① UV aging resistance: The test conditions were simulated natural UV light (340nm, irradiance 0.76W / m²). 2 Temperature 50±3℃, relative humidity 50±5%; can meet 500H.

[0036] ②Transmittance: the transmittance of glass in... The average transmittance decreased by less than 0.2% within the range.

[0037] ③ Abrasion resistance: 5N, velvet cloth, repeated 100 times. Excellent abrasion resistance; the water droplet angle of the hydrophobic film decreases by less than 5°, and the transmittance changes by less than 0.1%.

[0038] ④ Temperature shock resistance: A 72-hour high and low temperature cycle was performed, with each cycle consisting of 1 hour at low temperature (-40±2)℃ and 1 hour at high temperature (85±2)℃. No blistering, cracking, or peeling occurred on the lens surface coating, demonstrating good adhesion. The water droplet angle of the hydrophobic film decreased by less than 5°, and the transmittance changed by less than 0.1%.

[0039] Example 2

[0040] Hydrophobic film thickness test

[0041] Step 1) Deposit an anti-reflective coating on the surface of the optical lens to obtain a substrate, and cover half of the substrate with tape;

[0042] Step 2) Mix perfluorododecyltrichlorosilane and ethanol, stir well, filter out the suspended matter with a filter to obtain a transparent FDTS ethanol solution with a concentration of 0.5% w / w.

[0043] Step 3) Use a plastic dropper to draw up FDTS ethanol solution and drop it onto the center area of ​​the substrate surface. Use a spin coater at 3000-3500 r / min to evenly spread FDTS ethanol onto the substrate surface. Let it age at room temperature for 30 min to form a stable transparent hydrophobic film solution with a water droplet angle of 105-115° on the substrate surface.

[0044] Step 4) Transfer the substrate with the hydrophobic film solution to an oven and dry it at 180°C for 3 hours to cure. Then remove the tape.

[0045] See atomic force microscope (AFM) image for reference. Figure 2 As shown, the white particles in the lower left corner represent the area coated with FDTS solution. The difference between the two ends of the tape dividing line represents the film thickness, with a minimum value of -2nm and a maximum value of 3nm. See the profilometer scan image for reference. Figure 3 As shown, the optical non-contact profilometer displays the three-dimensional profile of the surface of the object being tested. The lowest value at both ends of the tape dividing line is 5nm, and the highest value is 10nm; it can be inferred that the film layer is around 5nm.

[0046] While specific embodiments of the present invention have been described above, those skilled in the art should understand that the specific embodiments described are merely illustrative and not intended to limit the scope of the invention. Modifications and variations made by those skilled in the art in accordance with the spirit of the invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A method for preparing a hydrophobic optical lens, characterized in that: Includes the following steps: (1) A layer of antireflective coating is deposited on the surface of an optical lens to obtain a substrate; (2) Mix FDTS and ethanol, stir well, filter, and obtain a transparent FDTS ethanol solution; (3) Take an FDTS ethanol solution and drop it onto the center of the substrate surface. Use a spin coater to evenly spread the FDTS ethanol solution onto the substrate surface and let it age to form a stable hydrophobic film solution on the substrate surface. (4) The substrate with the hydrophobic film solution is transferred to an oven to dry and cure, forming a hydrophobic film on the surface of the substrate, thus obtaining a hydrophobic optical lens.

2. The method for preparing a hydrophobic optical lens according to claim 1, characterized in that: The concentration of the FDTS ethanol solution in step (2) is 0.5% w / w.

3. The method for preparing a hydrophobic optical lens according to claim 1, characterized in that: The rotation speed of the spin coater in step (3) is 3000-3500 r / min.

4. The method for preparing a hydrophobic optical lens according to claim 1, characterized in that: In step (3), the water droplet angle of the hydrophobic film solution on the substrate surface is 105-115°.

5. The method for preparing a hydrophobic optical lens according to claim 1, characterized in that: The aging time in step (3) is 30 minutes.

6. The method for preparing a hydrophobic optical lens according to claim 1, characterized in that: The drying and curing temperature in step (4) is 180℃ and the time is 3h.

7. The method for preparing a hydrophobic optical lens according to claim 1, characterized in that: The thickness of the hydrophobic film in step (4) is 4-6 nm.

8. A hydrophobic optical lens prepared by any one of the preparation methods described in claims 1-7.

9. A hydrophobic optical lens according to claim 8, characterized in that: It includes an optical lens, on which an anti-reflective coating and a hydrophobic coating are sequentially disposed.

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