High-stability light-absorbing low-reflection film and preparation method thereof

Abstract

The invention discloses a high-stability light-absorption low-reflection film which comprises a substrate layer, an Al2O3 layer, Ti layers, SiO2 layers and a hydrophobic layer, wherein the Ti layers and the SiO2 layers are alternated with each other; wherein the sum of the total optical thicknesses of the Ti layers and the SiO2 layers which are alternated with each other is greater than 4.4726; the invention further discloses a preparation method of the high-stability light-absorption low-reflection film. According to the invention, the Ti layer with a higher refractive index is creatively selected to replace a traditional black film made of a high-refractive-index material, and the high-refractive-index material and the low-refractive-index material are mutually alternated, so that the effective refractive index of the film layer is close to the refractive index of the substrate layer; the problem that the spectral reflectivity is unstable due to the fact that a thin layer is too sensitive in the plating process of a traditional light-absorbing low-reflection film is solved, and the stability, compactness and other performance of the film layer are effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optical coating, and in particular to a high-stability light-absorbing and low-reflective film and a preparation method thereof. Background Art

[0002] At present, the traditional light-absorbing low-reflection film is a film formed by alternatingly depositing low-refractive index materials and high-refractive index materials on the surface of a PET substrate to achieve a spectroscopic anti-reflection effect. The traditional light-absorbing low-reflection film system in China is composed of alternating SiO2 layers and black film layers. The light-absorbing layer of the traditional light-absorbing low-reflection film is a specially made black film material. During the plating process, these black film materials are easily affected by the vacuum degree and other factors and are easily oxidized, thereby affecting the light absorption effect. That is, when the vacuum degree is lower than 2.0E-3Pa, the black film material is very easy to oxidize, resulting in low absorption rate, unstable reflection and other phenomena. Secondly, the average AR reflection value varies by 0.1% to 0.15%, and these errors often affect the reflection and light absorption effects of the light-absorbing low-reflection film. Summary of the Invention

[0003] In order to overcome the above technical problems, the present invention discloses a high-stability light-absorbing and low-reflective film and a preparation method thereof.

[0004] The technical solution adopted by the present invention to achieve the above-mentioned purpose is:

[0005] A high-stability light-absorbing and low-reflection film, which sequentially comprises a base layer, an Al2O3 layer, alternating Ti layers and SiO2 layers, and a hydrophobic layer;

[0006] The sum of the total optical thicknesses of the alternating Ti layers and the SiO2 layers is greater than 4.4726.

[0007] The above-mentioned high-stability light-absorbing and low-reflective film, wherein the single layer thickness of the Al2O3 is 50nm, the single layer thickness of the Ti layer is 14.64-200nm, the single layer thickness of the SiO2 layer is 75-105nm, and the single layer thickness of the hydrophobic layer is 10nm.

[0008] The above-mentioned high-stability light-absorbing and low-reflection film, wherein the light-absorbing and low-reflection film includes more than 8 layers in addition to the base layer.

[0009] In the above-mentioned high-stability light-absorbing and low-reflection film, the Ti layer includes at least 3 layers, and the SiO2 layer includes at least 3 layers.

[0010] The above-mentioned high-stability light-absorbing and low-reflection film, wherein the light-absorbing and low-reflection film includes 8 layers in addition to the base layer, namely, an Al2O3 layer, a first Ti layer, a first SiO2 layer, a second Ti layer, a second SiO2 layer, a third Ti layer, a third SiO2 layer and a hydrophobic layer.

[0011] The above-mentioned high-stability light-absorbing and low-reflective film, wherein the physical thickness of the Al2O3 layer is 50nm, the physical thickness of the first Ti layer is 200nm, the physical thickness of the first SiO2 layer is 102.72nm, the physical thickness of the second Ti layer is 28.96nm, the physical thickness of the second SiO2 layer is 75.44nm, the physical thickness of the third Ti layer is 14.56nm, the physical thickness of the third SiO2 layer is 76.82nm, and the physical thickness of the hydrophobic layer is 10nm.

[0012] The above-mentioned high-stability light-absorbing and low-reflection film, wherein the refractive index of the Al2O3 layer at a wavelength of 550nm is 1.65, the refractive index of the Ti layer at a wavelength of 550nm is 2.43, the refractive index of the SiO2 layer at a wavelength of 550nm is 1.46, and the refractive index of the hydrophobic layer at a wavelength of 550nm is 1.32.

[0013] In the above-mentioned high-stability light-absorbing and low-reflective film, the hydrophobic layer is a tetrafluoroethylene layer.

[0014] A method for preparing a high-stability light-absorbing and low-reflection film, wherein the method is used to prepare the above-mentioned high-stability light-absorbing and low-reflection film;

[0015] The preparation method comprises the following steps:

[0016] Step 1, pretreatment of the substrate layer;

[0017] Step 2, coating operation of the Al2O3 layer;

[0018] Step 3, coating operation of the Ti layer and the SiO2 layer;

[0019] Step 4: coating of the hydrophobic layer.

[0020] In the above-mentioned method for preparing a high-stability light-absorbing and low-reflective film, in steps 2 to 4, the coating conditions are:

[0021]

[0022]

[0023] The beneficial effects of the present invention are as follows: the present application innovatively selects the Ti layer with a higher refractive index (refractive index of 2.43 / 550nm) to replace the traditional high-refractive material black film (refractive index of 1.9 / 550nm), and the high and low refractive index materials are alternately used to make the equivalent refractive index of the film layer close to the refractive index of the substrate layer, so as to overcome the problem of unstable spectral reflectivity caused by excessive sensitivity of the thin layer during the plating process of the traditional light-absorbing low-reflective film, and effectively improve the stability, density and other properties of the film layer; wherein, using the Al2O3 layer as the base layer helps to improve The adhesion between the high film layer and the base layer, the Ti layer as a high refractive index material is mainly used to absorb visible light, and the SiO2 layer as a low refractive index material matching the Ti layer uses the interference effect to reduce the reflectivity, greatly optimizing the high light absorption and low reflection performance of the light-absorbing and low-reflection film, thereby effectively reducing light pollution. Secondly, the hydrophobic layer is added to effectively improve the surface hydrophobicity of the light-absorbing and low-reflection film, avoid energy loss caused by diffuse reflection caused by surface moisture, avoid stray light interference, and further optimize the high light absorption and low reflection performance of the light-absorbing and low-reflection film. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] The present invention will be further described below with reference to the accompanying drawings and examples.

[0025] Figure 1 Spectral curve reflectivity diagram of the light-absorbing and low-reflective films of Example 1 and Comparative Example 1 of the present invention;

[0026] Figure 2 Spectral curve transmittance diagram of the light-absorbing and low-reflective films of Example 1 and Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0027] The present invention is further described below by means of specific examples to make the technical solution of the present invention easier to understand and grasp, rather than to limit the present invention.

[0028] In this embodiment, unless otherwise specified, all reagents can be purchased on the market.

[0029] In this embodiment, unless otherwise specified, the methods used are all conventional methods.

[0030] The present invention provides a high-stability light-absorbing and low-reflective film, which sequentially comprises a base layer, an Al2O3 layer, alternating Ti layers and SiO2 layers, and a hydrophobic layer;

[0031] The sum of the total optical thicknesses of the alternating Ti layers and the SiO2 layers is greater than 4.4726.

[0032] Specifically, the present application innovatively selects the Ti layer with a higher refractive index (refractive index of 2.43 / 550nm) to replace the traditional high-refractive material black film (refractive index of 1.9 / 550nm), and the high and low refractive index materials are alternated to make the equivalent refractive index of the film layer close to the refractive index of the substrate layer, so as to overcome the problem of unstable spectral reflectivity caused by the excessive sensitivity of the thin layer during the plating process of the traditional light-absorbing low-reflective film, and effectively improve the stability, density and other properties of the film layer; wherein, using the Al2O3 layer as the base layer helps to improve the film layer The adhesion to the base layer, the Ti layer as a high refractive index material is mainly used to absorb visible light, and the SiO2 layer as a low refractive index material matching the Ti layer uses the interference effect to reduce the reflectivity, greatly optimizing the high light absorption and low reflection performance of the light-absorbing and low-reflection film, thereby effectively reducing light pollution. Secondly, the hydrophobic layer is added to effectively improve the surface hydrophobicity of the light-absorbing and low-reflection film, avoid energy loss caused by diffuse reflection caused by surface moisture, avoid stray light interference, and further optimize the high light absorption and low reflection performance of the light-absorbing and low-reflection film.

[0033] Preferably, the thickness of the single layer of Al2O3 is 50 nm, the thickness of the single layer of Ti layer is 14.64-200 nm, the thickness of the single layer of SiO2 layer is 75-105 nm, and the thickness of the single layer of the hydrophobic layer is 10 nm.

[0034] Preferably, the light-absorbing and low-reflective film includes more than 8 layers in addition to the base layer.

[0035] Preferably, the Ti layer includes at least 3 layers, and the SiO2 layer includes at least 3 layers.

[0036] In this embodiment, the light-absorbing low-reflection film includes 8 layers in addition to the base layer, namely, an Al2O3 layer, a first Ti layer, a first SiO2 layer, a second Ti layer, a second SiO2 layer, a third Ti layer, a third SiO2 layer and a hydrophobic layer.

[0037] Preferably, the physical thickness of the Al2O3 layer is 50nm, the physical thickness of the first Ti layer is 200nm, the physical thickness of the first SiO2 layer is 102.72nm, the physical thickness of the second Ti layer is 28.96nm, the physical thickness of the second SiO2 layer is 75.44nm, the physical thickness of the third Ti layer is 14.56nm, the physical thickness of the third SiO2 layer is 76.82nm, and the physical thickness of the hydrophobic layer is 10nm.

[0038] Preferably, the refractive index of the Al2O3 layer at a wavelength of 550nm is 1.65, the refractive index of the Ti layer at a wavelength of 550nm is 2.43, the refractive index of the SiO2 layer at a wavelength of 550nm is 1.46, and the refractive index of the hydrophobic layer at a wavelength of 550nm is 1.32.

[0039] Preferably, the hydrophobic layer is a tetrafluoroethylene (PTFE) layer.

[0040] The present invention also discloses a method for preparing a high-stability light-absorbing and low-reflection film, and the method is used to prepare the above-mentioned high-stability light-absorbing and low-reflection film;

[0041] The preparation method comprises the following steps:

[0042] Step 1, pretreatment of the substrate layer, including but not limited to ultrasonic cleaning, and the substrate layer is preferably but not limited to a glass substrate;

[0043] Step 2, coating operation of the Al2O3 layer: pre-melting Al2O3 on the surface of the base layer according to the coating conditions in Table 1, cooling and coating to obtain the Al2O3 layer;

[0044] Step 3, coating operation of the Ti layer and the SiO2 layer: according to the coating conditions in Table 1, Ti and SiO2 are pre-melted and cooled in sequence on the surface of the film layer obtained in Step 2, so as to obtain alternating Ti layers and SiO2 layers by coating;

[0045] Step 4, coating operation of the hydrophobic layer: coating a tetrafluoroethylene solution on the surface of the film layer obtained in step 2 to obtain the light-absorbing low-reflection film.

[0046] Preferably, in steps 2 to 4, the preparation conditions are shown in Table 1 below:

[0047] Table 1 Preparation conditions

[0048]

[0049]

[0050] The light-absorbing low-reflection film according to the present invention is now described in detail in the following embodiments:

[0051] Example 1: This example provides a high-stability light-absorbing and low-reflective film, which sequentially includes an Al2O3 layer, a first Ti layer, a first SiO2 layer, a second Ti layer, a second SiO2 layer, a third Ti layer, a third SiO2 layer, and a hydrophobic layer.

[0052] The physical thickness of the Al2O3 layer is 50 nm, the physical thickness of the first Ti layer is 200 nm, the physical thickness of the first SiO2 layer is 102.72 nm, the physical thickness of the second Ti layer is 28.96 nm, the physical thickness of the second SiO2 layer is 75.44 nm, the physical thickness of the third Ti layer is 14.56 nm, the physical thickness of the third SiO2 layer is 76.82 nm, and the physical thickness of the hydrophobic layer is 10 nm.

[0053] The refractive index of the Al2O3 layer at a wavelength of 550nm is 1.65, the refractive index of the Ti layer at a wavelength of 550nm is 2.43, the refractive index of the SiO2 layer at a wavelength of 550nm is 1.46, and the refractive index of the hydrophobic layer at a wavelength of 550nm is 1.32.

[0054] Comparative Example 1: This comparative example provides a light-absorbing low-reflection film, whose structure is the same as that of the light-absorbing low-reflection film in Example 1, except that the Ti layer in Example 1 is replaced by a black film layer of the same physical thickness; wherein the refractive index of the black film layer at a wavelength of 550 nm is 1.9.

[0055] The reflectivity and transmittance of the light-absorbing low-reflection films of Example 1 and Comparative Example 1 were measured. The detailed test results are shown in the figure. Figure 1 and Figure 2 shown.

[0056] like Figure 1 and Figure 2 As shown, the visible light reflectance of the light-absorbing low-reflection films of Example 1 and Comparative Example 1 in the 420-680 nm band is basically below 0.3%, and although the transmittance of the light-absorbing low-reflection films of Example 1 and Comparative Example 1 is both below 0.1%, the absorption rate of the light-absorbing low-reflection film of Example 1 to visible light is close to 99.9%.

[0057] The high-stability light-absorbing and low-reflection film of the present invention has the following advantages: the present application innovatively selects the Ti layer with a higher refractive index (refractive index of 2.43 / 550nm) to replace the traditional high-refractive material black film (refractive index of 1.9 / 550nm), and the high and low refractive index materials are alternately used to make the equivalent refractive index of the film layer close to the refractive index of the substrate layer, thereby overcoming the problem of unstable spectral reflectivity caused by the excessive sensitivity of the thin layer during the coating process of the traditional light-absorbing and low-reflection film, and effectively improving the stability, density and other properties of the film layer; wherein, the Al2O3 layer is used as the base layer , which helps to improve the adhesion between the film layer and the base layer. The Ti layer, as a high-refractive-index material, is mainly used to absorb visible light, and the SiO2 layer, as a low-refractive-index material matching the Ti layer, uses the interference effect to reduce the reflectivity, greatly optimizing the high light absorption and low reflection performance of the light-absorbing and low-reflection film, thereby effectively reducing light pollution. Secondly, the hydrophobic layer is added to effectively improve the surface hydrophobicity of the light-absorbing and low-reflection film, avoid energy loss caused by diffuse reflection caused by surface moisture, avoid stray light interference, and further optimize the high light absorption and low reflection performance of the light-absorbing and low-reflection film.

[0058] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Any person skilled in the art can, without departing from the scope of the present invention, utilize the above-disclosed technical means and technical content to make many possible variations and modifications to the present invention, or modify it into equivalent embodiments with equivalent variations. Therefore, any equivalent variations made in accordance with the shape, structure, and principle of the present invention that do not depart from the content of the present invention's technical solution should be included in the scope of protection of the present invention.

Claims

1. A high-stability light-absorbing and low-reflective film, characterized in that: It includes a base layer, an Al2O3 layer, alternating Ti layers and SiO2 layers, and a hydrophobic layer in sequence; The sum of the total optical thicknesses of the alternating Ti layers and SiO2 layers is greater than 4.4726.

2. The high-stability light-absorbing and low-reflective film according to claim 1, characterized in that: The single layer thickness of the Al2O3 is 50nm, the single layer thickness of the Ti layer is 14.64-200nm, the single layer thickness of the SiO2 layer is 75-105nm, and the single layer thickness of the hydrophobic layer is 10nm.

3. The high-stability light-absorbing and low-reflective film according to claim 2, characterized in that: The light-absorbing low-reflection film includes more than 8 layers except the base layer.

4. The high-stability light-absorbing and low-reflective film according to claim 3, characterized in that: The Ti layer includes at least 3 layers, and the SiO2 layer includes at least 3 layers.

5. The high-stability light-absorbing and low-reflective film according to claim 4, characterized in that: The light-absorbing low-reflection film includes 8 layers in addition to the base layer, which are an Al2O3 layer, a first Ti layer, a first SiO2 layer, a second Ti layer, a second SiO2 layer, a third Ti layer, a third SiO2 layer and a hydrophobic layer.

6. The high-stability light-absorbing and low-reflective film according to claim 5, characterized in that: The physical thickness of the Al2O3 layer is 50nm, the physical thickness of the first Ti layer is 200nm, the physical thickness of the first SiO2 layer is 102.72nm, the physical thickness of the second Ti layer is 28.96nm, the physical thickness of the second SiO2 layer is 75.44nm, the physical thickness of the third Ti layer is 14.56nm, the physical thickness of the third SiO2 layer is 76.82nm, and the physical thickness of the hydrophobic layer is 10nm.

7. The high-stability light-absorbing and low-reflective film according to claim 6, characterized in that: The refractive index of the Al2O3 layer at a wavelength of 550 nm is 1.65, the refractive index of the Ti layer at a wavelength of 550 nm is 2.43, the refractive index of the SiO2 layer at a wavelength of 550 nm is 1.46, and the refractive index of the hydrophobic layer at a wavelength of 550 nm is 1.

32.

8. The high-stability light-absorbing and low-reflective film according to claim 7, characterized in that: The hydrophobic layer is a tetrafluoroethylene layer.

9. A method for preparing a high-stability light-absorbing and low-reflective film, characterized in that: The preparation method is used to prepare the high-stability light-absorbing and low-reflective film as described in any one of claims 1 to 8; The preparation method comprises the following steps: Step 1, pretreatment of the substrate layer; Step 2, coating operation of the Al2O3 layer; Step 3, coating operation of the Ti layer and the SiO2 layer; Step 4, coating operation of the hydrophobic layer.

10. The method for preparing a high-stability light-absorbing and low-reflective film according to claim 9, characterized in that: In steps 2 to 4, the coating conditions are:

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