Anti-reflection film, assembly and device

Abstract

The invention discloses an anti-reflection film, an assembly and equipment, the anti-reflection film comprises a base material layer, and a hardened layer, a priming layer and an AR layer which are sequentially formed on one side of the base material layer, and plasma bombardment applied to a to-be-coated interface is kept at least during the preparation period of the hardened layer and / or the pretreatment period of the hardened layer and / or the preparation period of the priming layer. According to the method, the process adjustment of ion source bombardment is started in the pretreatment stage of the base material hardened layer and / or the base layer plating stage, so that the effect of enhancing the adhesion performance of the AR film is achieved.

Description

Technical Field

[0001] This invention belongs to the field of composite optical film technology, specifically relating to an anti-reflective film, component, and device. Background Technology

[0002] Existing products on the market have a large difference in interlayer stress and poor interlayer adhesion, which can cause them to peel off under certain destructive environments.

[0003] Therefore, in order to address the above-mentioned technical problems, it is necessary to provide an anti-reflective film, component, and device. Summary of the Invention

[0004] The purpose of this invention is to provide an anti-reflective film, component, and device.

[0005] To achieve the above objectives, a specific embodiment of the present invention provides the following technical solution:

[0006] An antireflective film includes a substrate layer and a hardening layer, a base layer and an AR layer sequentially formed on one side of the substrate layer, and maintains plasma bombardment applied to the interface to be coated at least during the preparation of the hardening layer and / or the pretreatment of the hardening layer and / or the preparation of the base layer.

[0007] In one or more embodiments of the present invention, the underlayer is deposited by ion sputtering with an inorganic material as the target material, and the inorganic material is selected from SiO2, Si, MgF2, SiO, HfO2, SnO2, Y2O3.

[0008] In one or more embodiments of the present invention, plasma bombardment is achieved by using graphite or tungsten as the ion source and argon as the auxiliary gas to bombard argon positive ions.

[0009] In one or more embodiments of the present invention, the parameters of plasma bombardment are set as follows: the ion source voltage is in the range of 300-1000V, the power is 300-400W, and the duty cycle is set to 100%.

[0010] In one or more embodiments of the present invention, the AR layer is obtained by alternating high-fold and low-fold layers, and the layer adjacent to the base layer is a high-fold layer.

[0011] In one or more embodiments of the present invention, the high-folding target material is selected from: niobium oxide, titanium oxide, zirconium oxide or zinc aluminum oxide.

[0012] In one or more embodiments of the present invention, the target material for the low-fold layer is selected from: silicon dioxide, aluminum oxide or magnesium fluoride.

[0013] In one or more embodiments of the present invention, the display component includes a carrier and an anti-reflective film disposed on the carrier.

[0014] In one or more embodiments of the present invention, a display device includes a display component.

[0015] In one or more embodiments of the present invention, the terminal device includes a display device and a power supply component.

[0016] Compared with existing technologies, the antireflective film, components, and equipment of this invention achieve enhanced adhesion performance of the AR film by adjusting the process of initiating ion source bombardment during the pretreatment of the substrate hardened coating surface and the undercoating stage. The key advantage lies in the novel coating process that simultaneously initiates ion source bombardment. The improved AR film has three major advantages: reduced stress and lower warpage; improved adhesion and better weather resistance; and stable antireflective and anti-reflective optical functions, with the film material's refractive index remaining unchanged despite the addition of ion source target material. Attached Figure Description

[0017] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0018] Figure 1 This is a schematic diagram of the structure of an antireflective film in one embodiment of the present invention; wherein 1 is a PET high-temperature protective film; 2 is a lower coating layer; 3 is a substrate layer; 4 is an upper coating layer / ion source treatment; 5 is a base coat / ion source treatment; 6 is a first high refractive index layer; 7 is a first low refractive index layer; 8 is a second high refractive index layer; and 9 is a second low refractive index layer.

[0019] Figure 2 This is a schematic diagram of three growth modes of magnetron sputtering;

[0020] Figure 3 The present invention provides a pair of proportion 1 reflection spectra in the visible light band: without ion source assistance;

[0021] Figure 4 The visible light reflectance spectrum of the antireflective film PET-AR film in Embodiment 1 of the present invention: pretreatment with a 300V ion source and bombardment of the underlying layer;

[0022] Figure 5 Comparison of the visible light reflectance spectra of the anti-reflection film of Comparative Example 1 after boiling in water for 1 hour with the HC surface of the substrate: no plasma bombardment (Comparative Example 1), HC surface of the substrate (blue line).

[0023] Figure 6This is a comparison of the visible light reflectance spectra of the anti-reflection film after boiling in water for 4 hours and the HC surface of the substrate in Embodiment 1 of the present invention: 300V ion source pretreatment and bombardment of the substrate (Example 1), HC surface of the substrate (blue line). Detailed Implementation

[0024] To enable those skilled in the art to better understand the technical solutions in this disclosure, the technical solutions of this invention will be clearly and completely described below in conjunction with the embodiments disclosed herein. Obviously, the described embodiments are only some embodiments of this disclosure, and not all embodiments. Based on the embodiments in this disclosure, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of this disclosure.

[0025] This invention relates to an anti-reflective film with superior adhesion performance and its preparation method, comprising a substrate layer, which can be a PET layer, a TAC layer, a transparent PI layer, or a PC layer, with a substrate thickness of 5.7-250 μm. An acrylic resin layer with a thickness of approximately 0.3-3.9 μm is coated onto the upper and lower surfaces of the substrate using a coating process. A 30-188 μm thick high-temperature protective film is adhered to the lower surface to prevent scratches from the film material by the rollers during the high-temperature coating process. Graphite material is used as the ion source target, and argon is used as the auxiliary gas. Before coating, a substrate hardening coating surface pretreatment process is performed, ionizing argon positive ions to bombard the substrate to be coated, reducing organic impurities such as moisture and improving coating quality. During the undercoating of inorganic materials such as SiO2 / Si / MgF2 / SiO / HfO2 / SnO2 / Y2O3 (2-10 nm), the graphite target ion source is turned on until the undercoating is completed. In this process, argon positive ions (plasma) bombard the film material, causing target atoms deviating from the layered growth to fill growth defects, increasing the adhesion between the hardened coating surface of the substrate and the coating layer. Subsequently, niobium pentoxide (Nb2O5, 10-150nm) and silicon dioxide (SiO2, 30-100nm) layers are repeatedly deposited on top of the underlayer. These four inorganic media are collectively referred to as the anti-reflection layer (AR layer). Due to the optical complementarity of the two media's special high and low refractive indices, high transmittance, and stable hardness and weather resistance, the reflected light between the coating layers interferes and cancels each other out, achieving the function of anti-reflection and anti-reflection. Finally, a layer of scratch-resistant and fingerprint-resistant liquid (mainly composed of perfluorocyclic ether, 2-80nm) is applied to the coating surface. Subsequent finished product testing results show that the adhesion time after boiling exceeds 4 hours; in terms of optical performance, the reflectivity in the main visible light band 400-700nm is below 1.0%.

[0026] like Figure 2As shown, magnetron sputtering deposition targets exhibit three atomic growth modes: island-like, columnar, and layered. These three growth modes can also lead to growth superposition, exacerbating growth defects in the coating, which in turn results in substandard coating adhesion. Reducing growth defects can improve important parameters of the coating, such as adhesion and stress.

[0027] Plasma enhancement can be used to reduce growth defects and improve adhesion. After plasma bombardment of islands and columnar structures, defects are filled, the interatomic spacing of the target material is reduced, the original layered structure is compacted, and the coating becomes smoother, enhancing the density and adhesion of the anti-reflective film. While adding an ion source target can effectively improve mechanical properties, overuse is not entirely beneficial. For example, it can complicate the coating process, place high demands on coating machinery, and increase production costs. Furthermore, a decrease in the optical performance of the anti-reflective coating is one of its drawbacks. The AR layer has very high requirements for material purity and thickness; even slight differences can lead to a sharp decline in optical performance. When the graphite ion source target is turned on, some carbon atoms from the graphite target may be sputtered onto the film material a second time, causing a change in the refractive index of the optical film. When the ion source target is turned on together with other sputtering targets, interactions between the targets may occur, causing changes in the original sputtering efficiency and thus altering the coating thickness. Therefore, these two reasons explain why the use of ion source targets can lead to a decrease in the optical performance of the anti-reflective film. Activating graphite ion target bombardment during the pretreatment stage of the substrate HC surface and during the undercoating stage can improve both mechanical properties and ensure stable optical performance. This is because the undercoating layer (such as SiO2, which is viscous at high temperatures) has a certain degree of viscosity and is very thin, so improving this layer will not affect the anti-reflective performance. On the other hand, this layer mainly exhibits mechanical functions. The difference in the coefficient of thermal expansion between organic substrates such as PET and inorganic layers such as Si is significant, resulting in high film warpage. Higher stress leads to easier coating peeling and poorer adhesion. Therefore, by activating graphite ion target bombardment enhancement only during the undercoating stage, excellent mechanical properties and stable optical performance can be guaranteed simultaneously.

[0028] This invention can be achieved through the following scheme:

[0029] A small-scale magnetron sputtering coating machine is used. The coating equipment has a cavity containing six planar targets and one graphite ion source target. Targets 1 and 2 are silicon metal targets, sharing the same magnetic flux (MF) power supply, while targets 5 and 6 are niobium pentoxide targets, also sharing a different MF power supply. The process involves: ② Placing the substrate on a roller and drawing a vacuum. Coating can begin when the vacuum reaches below 1.5E-5 Pa. ③ Sequentially blocking targets 1 and 2, targets 5 and 6, and the graphite ion source target with baffles, then sequentially energizing the targets. The process continues until the voltage, power, and other parameters stabilize, taking approximately 30 minutes. ④ After bombarding the substrate with the ion source, the ion source power is kept on to deposit the bottom layer of Si / SiO2. After this, the ion source target is turned off, and the remaining AR layers are deposited according to the film deposition process. ⑤ After coating, an anti-fingerprint liquid is sprayed using a sprayer. After baking and settling, an anti-reflective coating improved sample is obtained.

[0030] Step ④ of the process involved adjustments to the ion source enhancement. The pretreatment process and the initial undercoating did not utilize additional ion source enhancement measures. On one hand, enhanced plasma bombardment during the substrate HC surface pretreatment effectively removes moisture and other impurities from the substrate surface; residual substances negatively impact coating quality. On the other hand, plasma enhancement effectively improves the adhesion of the film material, increasing its lifespan. The ion source voltage range is approximately 300-1000V, with a duty cycle set to 100%.

[0031] Examples 1-3

[0032] In this embodiment, the substrate layer is a PET layer with a thickness of 50 μm. An acrylic resin layer with a thickness of 3 μm is coated onto both the upper and lower surfaces of the substrate using a coating process. A 50 μm thick high-temperature protective film is then bonded to the lower surface. A 0.2 nm thick SiO2 underlayer is deposited on the upper surface. Following this, a first layer of niobium pentoxide (Nb2O5, 30 nm) and silicon dioxide (SiO2, 50 nm) is deposited on top of the underlayer. A second layer of niobium pentoxide and silicon dioxide, with thicknesses of 100 nm and 110 nm respectively, is then deposited on top of this. Figure 1 As shown.

[0033] During preparation, the HC coating surface of the substrate was pretreated with plasma bombardment, and plasma bombardment was also maintained during the undercoating process. The plasma bombardment was achieved by using graphite as the ion source target and argon as the auxiliary gas. Examples 1-3 used ion source target voltages of 300V, 500V, and 700V respectively, thus obtaining samples one-three.

[0034] The only difference between Comparative Example 1 and Example 1 is that all plasma bombardment was eliminated.

[0035] The only difference between Comparative Example 2 and Example 1 is that the plasma bombardment in the undercoating stage is omitted.

[0036] The only difference between Comparative Example 3 and Example 1 is that tungsten material is used as the ion source target (power supply voltage is 300V).

[0037] The warpage test is a macroscopic representation of the interlayer stress in the micro / nano structure of optical films. Conventional PET-AR films and PET-AR films pretreated with the HC surface of graphite ion source substrates and bombarded with the underlayer are cut into A4 size along the same coating direction. After being placed on a flat table and left to stand for one minute, the warpage of the four corners of the AR film is compared.

[0038]

[0039] The average warpage values ​​of Comparative Examples 1-3 were 2.6 mm, 2.35 mm, and 2.02 mm, respectively. The average warpage values ​​of the three AR films pretreated with the HC surface of the graphite ion source substrate and bombarded with the underlayer were 1.92 mm, 1.47 mm, and 1.12 mm, respectively. Data shows that the warpage improvement is very significant after using the ion source; within the range of 300V-700V, the higher the voltage of the ion source, the better the improvement in warpage. A major reason for the high warpage is the huge difference in the coefficients of thermal expansion between the substrate and the AR layer. For example, the coefficient of thermal expansion of PET material is 8×E(-5) / ℃, while that of SiO2 material is 5×E(-7) / ℃, a difference of two orders of magnitude. Under the high temperature conditions of approximately 200℃ in the coating machine, the AR layer adheres to the HC surface of the PET substrate. As the coating temperature drops to room temperature at the end, the shrinkage of the PET substrate is much greater than that of the AR layer, leading to the risk of cracking and severe warpage of the optical film. Such warping causes significant damage to AR films, especially outdoors or under high-intensity friction, greatly shortening their lifespan. Experimental data shows that by increasing ion source bombardment of the substrate, this problem is effectively mitigated.

[0040] Boiled Hundreds of Cubes Experiment

[0041]

[0042] The water-boiling cross-cut adhesion test is a method to examine the coating adhesion performance of films under extreme high temperature and humidity environments. According to standard ISO 2409, the more stringent the requirement, the higher the cross-cut adhesion test score is from 0B to 5B. As shown in Table 2, Comparative Examples 1-2 achieved a 0B cross-cut adhesion score after 1 hour of boiling, with large areas of AR layer peeling off and significant color difference. Comparative Example 3 achieved a 0B cross-cut adhesion score after 2 hours of boiling, showing a significant improvement compared to Comparative Examples 1-2. Examples 1-3 maintained a 5B cross-cut adhesion score after 4 hours of boiling, with a smooth and clean cross-cut area and no signs of peeling. The samples with improved ion sources exhibited longer water-boiling resistance and better resistance to extreme environments, indicating that plasma pretreatment significantly enhanced the adhesion of the AR film.

[0043] Optical performance test after boiling

[0044] To more accurately understand the enhancing effect of plasma bombardment on the antireflective film, the optical performance of the samples before and after boiling in the visible light band will be measured using an Olympus reflectometer, with Comparative Example 1 and Example 1 as examples.

[0045] The use of ion source targets can lead to secondary sputtering of carbon atoms, contaminating the film material and altering its refractive index. Furthermore, interactions between targets can affect sputtering efficiency and film thickness, thereby reducing the optical performance of the antireflective film. Therefore, the process range for using ion source targets should be as close as possible to the underlayment stage, which should not compromise optical performance. Figure 3 and Figure 4 The visible light reflectance spectra are those of Comparative Example 1 and Example 1, respectively. Figure 3 The total light transmittance of Comparative Example 1 is 96.21%, and the reflectance in the main visible light band of 400nm-700nm is 0.48%. Figure 2 The total light transmittance of Example 1 is 95.84%, and the reflectance in the main visible light band of 400nm-700nm is 0.70%. Both reflectances are below 1%, indicating a stable anti-reflection effect. This demonstrates that using an ion source target in the pretreatment and undercoating stages will not cause distortion in the visible light reflectance spectrum.

[0046] Typical boiling water tests will always show hydrolysis because water has a certain degree of corrosiveness, and this phenomenon is particularly severe in boiling water at 100°C. Therefore, to determine whether the AR layer is peeling off or hydrolyzing, it is necessary to analyze it in conjunction with the reflectivity curve. Generally, it is considered that if the rate of peeling is slower than the rate of hydrolysis, the adhesion enhancement is effective. Figure 5 and Figure 6 The images show the optical reflectance of the 100-grid area after boiling for a period of time for the two antireflective films, Comparative Example 1 and Example 1. In Comparative Example 1, after boiling for 1 hour, the overall reflectance of the 100-grid area is very close to that of the substrate (blue line). This image indicates that the AR layer has completely detached, and the reflectance shows that the hardened HC layer beneath the AR layer has also detached to some extent. In contrast, [the image shows...] Figure 6 The overall reflectivity of Example 1 is significantly higher than that of the substrate (blue line). Calculations show that the AR layer in Example 1 exhibits partial hydrolysis in the second high-refractive-index layer, indicating that the underlying AR layer remains intact, demonstrating the stable presence of the SiO2 substrate and its adhesion-enhancing effect. Ion source bombardment of the PET-AR film substrate significantly improved its weather resistance and mechanical properties in the water-based cross-cut adhesion test, proving the effectiveness of this method in enhancing adhesion.

[0047] Graphite targets were used as the ion source. Graphite has a high secondary electron emission coefficient. High-energy argon ions bombarded the graphite target under an electric field, causing carbon atoms to be ejected with new free secondary electrons. These free secondary electrons were bound to the target surface by a magnetic field and continued to collide with argon atoms to generate even denser plasma. The plasma bombarded the film surface under the electric field, achieving the functions of cleaning, compacting, and re-arranging the atoms in the coating. After the plasma bombarded the AR layer islands and columnar structures, the defects were filled and compacted, increasing the density and adhesion of the anti-reflective coating. In this process, although the atomic sputtering efficiency of the graphite target is very low, some carbon atoms or the interactions between the target materials still have a significant impact on the refractive index of the film. Therefore, the ion source enhancement operation was limited to the pretreatment stage and the undercoat layer to enhance the adhesion between the organic and inorganic layers; at the same time, the refractive index of the AR layer was not contaminated to ensure stable anti-reflective performance.

[0048] The only difference between Examples 4-5 and Example 1 is that Example 4 uses a 300W RF power supply with a field frequency of 13.56MHz to power the Si target; Example 5 uses a 400W RF power supply with a field frequency of 13.56MHz to power the Si target.

[0049] Further investigation revealed that generating sufficient plasma is crucial for optimizing the adhesion process. Besides adding a graphite ion source, replacing the radio frequency (RF) power supply can achieve the same result. The RF power supply directly increases the plasma density; its field frequency is 13.56 MHz. Electrons oscillate at high frequencies under the electric field, significantly increasing the collision frequency with argon atoms and releasing more secondary electrons and plasma. The table below compares the water boiling tests of the antireflective film samples after adding the RF power supply. Example 4 achieved 1.5 hours of boiling (5B), and Example 5 achieved 2 hours (5B). This represents a significant improvement compared to the 1 hour (0B) of the original antireflective film sample. This demonstrates that adding the RF power supply is also an effective method for improving film adhesion.

[0050]

[0051] From a microscopic perspective, enhancing the density of the film material, besides the crucial factor of plasma density, is also related to the impact intensity of the plasma bombarding and filling coating defects, or in other words, the amount of momentum carried by the plasma. Adding an auxiliary anode at the roller end where the substrate is placed may achieve this goal. The roller end is connected to the negative terminal of the power supply, separated by a suitable insulating material such as ceramic to prevent damage to the film material from direct current. After energization, the potential at the substrate end is negative, and the positively charged plasma is accelerated under the auxiliary electric field until it impacts the substrate. In this process, the plasma is endowed with additional momentum, which can improve the filling efficiency of coating defects, macroscopically manifesting as improved film adhesion. The addition of a graphite ion source mentioned earlier actually increases plasma density and can also increase plasma momentum in the future. Combining the use of both a graphite ion source and an auxiliary anode may greatly benefit the optical film industry.

[0052] It will be apparent to those skilled in the art that this disclosure is not limited to the details of the exemplary embodiments described above, and that this disclosure can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of this disclosure is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within this disclosure. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0053] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. An antireflective film, comprising a substrate layer, and a hardening layer, a base layer, and an AR layer sequentially formed on one side of the substrate layer, characterized in that, Plasma bombardment applied to the interface to be coated is maintained at least during the preparation of the hardened layer and / or the pretreatment of the hardened layer and / or the preparation of the undercoat.

2. The antireflective film according to claim 1, characterized in that, The underlayer is deposited by ion sputtering using inorganic materials as the target material. The inorganic materials are selected from SiO2, Si, MgF2, SiO, HfO2, SnO2, and Y2O3.

3. The antireflective film according to claim 1, characterized in that, The plasma bombardment uses graphite or tungsten as the ion source and argon as the auxiliary gas.

4. The antireflective film according to claim 1, characterized in that, The parameters for plasma bombardment are set as follows: ion source voltage is 300-1000V, power is 300-400W, and duty cycle is 100%.

5. The antireflective film according to claim 1, characterized in that, The AR layer is obtained by alternating high-fold and low-fold layers, and the layer adjacent to the base layer is a high-fold layer.

6. The antireflective film according to claim 5, characterized in that, The target material for the high-folding layer is selected from: niobium oxide, titanium oxide, zirconium oxide, or zinc aluminum oxide.

7. The antireflective film according to claim 5, characterized in that, The target material for the low-fold layer is selected from: silicon dioxide, aluminum oxide, or magnesium fluoride.

8. A display component, comprising a carrier and an antireflective film disposed on the carrier according to any one of claims 1-7.

9. A display device, comprising the display component according to claim 8.

10. A terminal device, including the display device and power supply component according to claim 9.

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