Multifunctional display integrated black optical film and preparation method thereof

Abstract

The invention discloses a multifunctional display integrated black optical film and a preparation method thereof. The multifunctional display integrated black optical film comprises a pressure sensing type adhesive layer, an anti-impact layer, a transparent base material, a hardened layer, an anti-dazzle layer, a wide-angle optical antireflection layer and an anti-fingerprint layer which are sequentially stacked. Aiming at the defects that an existing wet-process antireflection film material is difficult to realize near-zero reflection of a visible light wave band, poor in color neutrality, greatly influenced by deformation and the like, design and improvement are performed from the aspects of design and regulation of a multi-layer antireflection optical structure, construction of a hydrophobic surface and the like; the preparation of the flexible display optical film which has an integrated black display effect and has high optical transmittance and mechanical stability and is hydrophobic and oleophobic is realized through an integrated manufacturing process. According to the wide-angle optical antireflection film, near-zero reflection of a visible light wave band can be achieved, good color neutrality is kept, and the influence of deformation on the wide-angle optical antireflection film is weak.

Description

Technical Field

[0001] The present invention relates to the field of antireflection, and particularly to a multifunctional integrated black display optical film and a preparation method thereof. Background Art

[0002] Optical antireflection technology is a light control technology that reduces or eliminates the interface reflection of light and enhances the light transmission by using the principle of destructive interference of light. According to the antireflection structure design, optical antireflection technology can be roughly divided into two categories: (1) Antireflection based on isotropic uniform single-layer or simple multi-layer dielectric films ( Figure 1 as shown in A), the principle of which is to make the reflected light from the upper and lower interfaces interfere destructively by selecting or constructing a thin film with appropriate optical parameters to achieve the purpose of antireflection and enhanced light transmission. This method has a simple principle, and through material design, artificial structures or materials with appropriate equivalent optical parameters can be screened out, and wide-band and omnidirectional antireflection can be achieved; (2) Antireflection based on refractive index gradient-varying media ( Figure 1 as shown in B), the principle of which is to utilize a multi-layer film system with refractive index gradient properties or construct a periodic micro-structure system with a gradient change in the structural scale along the light incident direction to form a refractive index gradient change. Since there is no abrupt interface, the reflectivity of the incident light is greatly reduced. However, the manufacturing of periodic micro-structures strongly depends on high-precision micro-nano processing technology, with a high technical barrier and it is difficult to achieve large-scale mass production.

[0003] In the field of OLED / LCD displays, antireflection technology is mainly used to reduce the reflection interference on the screen surface, improve the display image contrast, and significantly enhance the user viewing comfort under outdoor or strong light conditions, while reducing the power consumption of display devices. With the progress of science and technology, new display technologies represented by OLED flexible displays have attracted wide interest in the industrial and academic circles. However, the rigid transparent glass cover plate of its display device is replaced by a flexible and bendable polymer film. To ensure the contrast, brightness, and resolution of the device display image quality, higher requirements are put forward for aspects such as the optical transmittance and structural stability of the polymer film cover plate, and there is an urgent need to develop new antireflection technologies suitable for flexible displays. This patent aims at the technical pain points such as the difficulty in achieving near "zero" reflection in the visible light band, poor color neutrality, and large deformation influence in the preparation of antireflection film materials by the existing wet coating process. It is designed and constructed from aspects such as the development of optically viscoelastic nanocomposites, the design and regulation of multi-layer antireflection optical structures, and the construction of hydrophobic surfaces, and realizes the integrated black display effect through an integrated manufacturing process, and has a high optical transmittance, mechanical stability, and hydrophobic and oleophobic flexible display optical film.

[0004] The current anti-reflection structured film material for flexible displays is prepared by alternately wet-coating high refractive index (HR) and low refractive index (LR) resin coatings onto the surface of a flexible substrate. Limited by the narrow refractive index adjustment range of the resin, it can only achieve low reflection at a single wavelength (@550nm), and the average reflectance in the blue-violet and red light bands is >5%, showing a serious color deviation phenomenon. It is difficult to achieve near-zero reflection in the entire visible light band. Patent CN 118483774A can reduce or avoid the generation of interference fringes while ensuring the anti-reflection effect of the anti-reflection film by controlling the absolute value of the refractive index difference between the pre-coated bottom layer and the hard coating to ≤0.04, improving the clarity of the image presented on the display screen with the anti-reflection film. However, the overall residual light reflectance is still as high as 1.5%. Patent CN 118377071A uses SiAl rotary targets with different ratios to control the film layer thickness through roll-to-roll magnetron sputtering and combines wet etching and organic vapor deposition technologies to prepare a super-hydrophobic nanoporous silica wide-angle AR film. Its process flow is relatively complex, and the measured optical reflectance value remains at about 2%, unable to effectively achieve the "integration black" effect of the display.

[0005] In addition, due to the optical path differences at different incident angles and the sharp change in the refractive index between layers, the existing alternating coating structure can only achieve anti-reflection within a specific incident angle range (8°), and it is difficult to precisely control the light reflection behavior at large angles (45°). Summary of the Invention

[0006] The technical problem to be solved by the present invention is to provide a multi-functional integrated black optical film for displays and its preparation method in view of the above deficiencies in the prior art. Through the design of a multi-layer anti-reflection film system, the design and construction of a fused micro / nano-scale laminated system, and the integration of an "integrated" preparation process, the present invention not only enhances the full-band optical anti-reflection performance at an ultra-wide angle (45° viewing angle), but also further integrates impact resistance, fingerprint resistance, and anti-glare functions into the optical base film through integrated manufacturing.

[0007] To solve the above technical problems, the technical solution adopted by the present invention is: In the first aspect of the present invention, a multi-functional integrated black optical film for displays is provided, including a pressure-sensitive adhesive layer, an impact-resistant layer, a transparent substrate, a hardening layer, an anti-glare layer, a wide-angle optical anti-reflection layer, and a fingerprint-resistant layer that are sequentially laminated.

[0008] Preferably, the pressure-sensitive adhesive layer is prepared from an acrylic resin through a coating process.

[0009] Preferably, the impact-resistant layer is prepared from a transparent polyurethane through a coating process.

[0010] Preferably, the transparent substrate is a roll material composed of a mixture of one or more of the following materials: polyethylene naphthalate (PEN), polyethylene terephthalate (PET), triacetyl cellulose (TAC), cycloolefin copolymer (COP), cycloolefin polymer (COC), polycarbonate, and the thickness of the transparent substrate is 0.023 mm to 2 mm.

[0011] Preferably, the hardening layer is prepared by a coating process using a hexa-functional polyurethane acrylate resin oligomer as a raw material.

[0012] Preferably, the anti-glare layer is prepared by a coating process using an anti-glare coating solution as a raw material, and the anti-glare coating solution contains silica microparticles with a mass ratio of 0.1-1%.

[0013] Preferably, the wide-angle optical antireflection layer is formed by alternately stacking M first refractive index layers and M second refractive index layers in sequence starting from the side close to the transparent substrate, where M = 2, 3 or 4;

[0014] Both the first refractive index layer and the second refractive index layer are prepared by a magnetron sputtering process. The material of the first refractive index layer is Nb2O5, and the second refractive index material is SiO2.

[0015] Preferably, the anti-fingerprint layer is prepared by an organic evaporation process using perfluoropolyether as a raw material.

[0016] In the second aspect of the present invention, a method for preparing the multifunctional display integrated black optical film as described above is provided, including the following steps:

[0017] S1. Coating a hexa-functional polyurethane acrylate resin oligomer on the upper surface of the transparent substrate, and preparing a hardening layer after UV curing;

[0018] S2. Coating an anti-glare coating solution on the upper surface of the hardening layer, and preparing an anti-glare layer after UV curing;

[0019] S3. Using a magnetron sputtering process, starting from the upper surface of the anti-glare layer, alternately stacking M first refractive index layers and M second refractive index layers in sequence to prepare a wide-angle optical antireflection layer;

[0020] S4. Using perfluoropolyether as a raw material, preparing an anti-fingerprint layer on the upper surface of the wide-angle optical antireflection layer by an organic evaporation process;

[0021] S5. Coating transparent polyurethane on the lower surface of the transparent substrate, and preparing an impact-resistant layer after thermal curing;

[0022] S6. Coating an acrylic resin on the lower surface of the impact-resistant layer, and preparing a pressure-sensitive adhesive layer after thermal curing to finally obtain the optical film.

[0023] Preferably, the method for preparing the multifunctional display integrated black optical film comprises the following steps:

[0024] S1. Using a 150 - 250 mesh micro - gravure roll, coat a hexa - functional polyurethane acrylate resin oligomer on the upper surface of the transparent substrate, and form a hardened layer after UV curing. The coating line speed is 3 - 10 m / min, and the UV curing energy is 100 - 400 mJ / cm 2 ;

[0025] S2. Using a 150 - 250 mesh micro - gravure roll, coat an anti - glare coating solution on the upper surface of the hardened layer, and form an anti - glare layer after UV curing. The coating line speed is 3 - 10 m / min, and the UV curing energy is 100 - 400 mJ / cm 2 ;

[0026] S3. Using a magnetron sputtering process, starting from the upper surface of the anti - glare layer, alternately stack M first refractive index layers and M second refractive index layers in sequence to form a wide - angle optical antireflection layer; the magnetron sputtering process parameters are: working pressure 0.15 - 0.6 Pa, coating running speed 0.5 - 2 m / min; M = 2, 3 or 4;

[0027] S4. Using perfluoropolyether as the raw material, prepare an anti - fingerprint layer on the upper surface of the wide - angle optical antireflection layer by an organic vapor deposition process. The organic vapor deposition process parameters are: working pressure 2.5 - 10×10 -3 Pa, liquid flow rate 0.25 - 1 mL / min, evaporation temperature 300 - 350 °C;

[0028] S5. Using a 150 - 200 mesh micro - gravure roll, coat transparent polyurethane on the lower surface of the transparent substrate, and form an impact - resistant layer after thermal curing. The coating line speed is 3 - 10 m / min, and the thermal curing temperature is 90 - 120 °C;

[0029] S6. Using a 150 - 200 mesh micro - gravure roll, coat an acrylic resin on the lower surface of the impact - resistant layer, and form a pressure - sensitive adhesive layer after thermal curing to finally obtain the optical film. The coating line speed is 3 - 10 m / min, and the thermal curing temperature is 90 - 120 °C.

[0030] The beneficial effects of the present invention are:

[0031] The present invention provides a multifunctional display integrated black optical film and a preparation method thereof. Aiming at the deficiencies of existing wet anti-reflection film materials, such as difficulty in achieving near "zero" reflection in the visible light band, poor color neutrality, and large influence by deformation, the present invention designs and improves from aspects such as the design and regulation of a multilayer anti-reflection optical structure and the construction of a hydrophobic surface, and realizes the preparation of a display integrated black effect and a flexible display optical film with high optical transmittance, mechanical stability, and hydrophobic and oleophobic properties through an integrated manufacturing process. The wide-angle optical anti-reflection film of the present invention can achieve near "zero" reflection in the visible light band, maintain good color neutrality, and be slightly affected by deformation and other properties. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is the basic principle of optical anti-reflection technology;

[0033] Figure 2 is a schematic structural diagram of the multifunctional display integrated black optical film of the present invention;

[0034] Figure 3 is a flowchart of the preparation method of the multifunctional display integrated black optical film of the present invention;

[0035] Figure 4 are the test results of the structural thickness and reflectivity of the wide-angle optical anti-reflection layer in Examples 1 to 3;

[0036] Figure 5 are the test results of the core evaluation indexes of integrated black;

[0037] Figure 6 are the comparison results of the reflectivity curves between the dry process and the wet process. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] The following further describes the present invention in detail with reference to embodiments, so that those skilled in the art can implement it according to the description in the specification.

[0039] It should be understood that the terms such as "having", "comprising", and "including" used herein do not exclude the presence or addition of one or more other elements or their combinations.

[0040] Unless otherwise specified, the test methods used in the following embodiments are all conventional methods. The materials, reagents, etc. used in the following embodiments can all be obtained from commercial channels unless otherwise specified. Those not specified in the following embodiments are carried out according to conventional conditions or the conditions recommended by the manufacturer. Those reagents or instruments not indicating the manufacturer can all be conventional products that can be purchased commercially.

[0041] The present invention provides a multifunctional integrated display black optical film, which includes a pressure-sensitive adhesive layer L1, an impact-resistant layer L2, a transparent substrate L3, a hardening layer L4, an anti-glare layer L5, a wide-angle optical anti-reflection layer L6, and an anti-fingerprint layer L7 that are sequentially stacked.

[0042] In a preferred embodiment, the pressure-sensitive adhesive layer is made of acrylic resin and prepared by a coating process. This layer has good optical transmittance, achieving very good optical transmission and bonding characteristics, and the adhesive layer itself has excellent anti-aging performance.

[0043] In a preferred embodiment, the impact-resistant layer is made of transparent polyurethane and prepared by a coating process. The impact-resistant layer belongs to an optical non-Newtonian fluid adhesive layer. The material of this layer is transparent and very impact-resistant, and can effectively protect the display screen from external impact damage for a long time.

[0044] In a preferred embodiment, the transparent substrate is a roll made of a mixture of one or more of the following materials: polyethylene naphthalate (PEN), polyethylene terephthalate (PET), triacetyl cellulose (TAC), cycloolefin copolymer (COP), cycloolefin polymer (COC), polycarbonate. The thickness of the transparent substrate is 0.023 mm to 2 mm.

[0045] In a preferred embodiment, the hardening layer is made of a hexa-functional polyurethane acrylate resin oligomer and prepared by a coating process. A high-hardness optical viscoelastic nanocomposite material is used to strengthen the structural strength and wear resistance of the anti-reflection film.

[0046] In a preferred embodiment, the anti-glare layer is made of an anti-glare coating solution and prepared by a coating process. The anti-glare coating solution contains micron-sized silicon oxide particles with a mass ratio of 1% - 60%. Different anti-glare effects are achieved by adjusting the content of micron-sized silicon oxide particles in the coating solution.

[0047] In a preferred embodiment, the wide-angle optical anti-reflection layer is composed of M first refractive index layers and M second refractive index layers that are alternately stacked in sequence starting from the side close to the transparent substrate, where M = 2, 3, or 4;

[0048] Both the first refractive index layer and the second refractive index layer are prepared by a magnetron sputtering process. The material of the first refractive index layer is Nb2O5, and the second refractive index material is SiO2. The wide-angle optical anti-reflection layer uses a multi-layer composite structure dielectric film of high and low refractive index materials to achieve near "zero" reflection, low color deviation, and ultra-wide-angle anti-reflection in the visible light band.

[0049] In a preferred embodiment, the anti-fingerprint layer is made of perfluoropolyether and prepared by an organic vapor deposition process. An organic vapor deposition is used to construct a fluorine-containing organic molecular layer on the surface of the wide-angle optical anti-reflection layer to improve its hydrophobic, oleophobic, and anti-fingerprint properties.

[0050] The present invention also provides a method for preparing the multifunctional display integrated black optical film as above, comprising the following steps:

[0051] S1. Coating a hexa-functional polyurethane acrylate resin oligomer on the upper surface of a transparent substrate, and preparing a hardened layer after UV curing;

[0052] S2. Coating an anti-glare coating liquid on the upper surface of the hardened layer, and preparing an anti-glare layer after UV curing;

[0053] S3. Using a magnetron sputtering process, starting from the upper surface of the anti-glare layer, alternately stacking M first refractive index layers and M second refractive index layers in sequence to prepare a wide-angle optical anti-reflection layer;

[0054] S4. Using perfluoropolyether as a raw material, preparing an anti-fingerprint layer on the upper surface of the wide-angle optical anti-reflection layer by an organic evaporation coating process;

[0055] S5. Coating transparent polyurethane on the lower surface of the transparent substrate, and preparing an impact-resistant layer after thermal curing;

[0056] S6. Coating an acrylic resin on the lower surface of the impact-resistant layer, and preparing a pressure-sensitive adhesive layer after thermal curing to finally obtain the optical film.

[0057] In a preferred embodiment, the method for preparing the multifunctional display integrated black optical film comprises the following steps:

[0058] S1. Using a 150-250 mesh micro-embossing roll to coat a hexa-functional polyurethane acrylate resin oligomer on the upper surface of a transparent substrate, and preparing a hardened layer after UV curing, with a coating line speed of 3-10 m / min and a UV curing energy of 100-400 mJ / cm 2 ;

[0059] S2. Using a 150-250 mesh micro-embossing roll to coat an anti-glare coating liquid on the upper surface of the hardened layer, and preparing an anti-glare layer after UV curing, with a coating line speed of 3-10 m / min and a UV curing energy of 100-400 mJ / cm 2 ;

[0060] S3. Using a magnetron sputtering process, starting from the upper surface of the anti-glare layer, alternately stacking M first refractive index layers and M second refractive index layers in sequence to prepare a wide-angle optical anti-reflection layer; the magnetron sputtering process parameters are: working pressure 0.15-0.6 Pa, coating running speed 0.5-2 m / min; M = 2, 3 or 4;

[0061] S4. Using perfluoropolyether as the raw material, an anti-fingerprint layer is prepared on the upper surface of the wide-angle optical anti-reflection layer by an organic vapor deposition process. The parameters of the organic vapor deposition process are as follows: the working pressure is 2.5 - 10×10 -3 Pa, the liquid flow rate is 0.25 - 1 mL / min, and the evaporation temperature is 300 - 350 °C;

[0062] S5. Using a 150 - 200 mesh micro-embossed roll, a transparent polyurethane is coated on the lower surface of the transparent substrate, and an impact-resistant layer is prepared after thermal curing. The coating line speed is 3 - 10 m / min, and the thermal curing temperature is 90 - 120 °C;

[0063] S6. Using a 150 - 200 mesh micro-embossed roll, an acrylic resin is coated on the lower surface of the impact-resistant layer, and a pressure-sensitive adhesive layer is prepared after thermal curing, and finally an optical film is obtained. The coating line speed is 3 - 10 m / min, and the thermal curing temperature is 90 - 120 °C.

[0064] In terms of the preparation technology, the process of the present invention integrates micro / nano-scale coating, roll-to-roll magnetron sputtering, and organic vapor deposition "integrated" preparation technology, forming a low-cost and high-efficiency anti-reflection film production technology with the full-process roll-to-roll process as the core, which will subvert the traditional single-coating anti-reflection film manufacturing technology and achieve an overall leap in its comprehensive performance.

[0065] The above is the overall concept of the present invention. Hereinafter, detailed examples and comparative examples are provided on this basis to further illustrate the present invention.

[0066] The structures and preparation methods of the multifunctional display integrated black optical films provided in the following examples are generally similar, and the main difference lies in the wide-angle optical anti-reflection layer. The overall preparation process is as follows:

[0067] S1. Using a 200 mesh micro-embossed roll, a hexa-functional polyurethane acrylate oligomer is coated on the upper surface of the transparent substrate (PET, with a thickness of 0.1 mm), and a hardened layer is prepared after UV curing. The coating line speed is 5 m / min, and the UV curing energy is 250 mJ / cm 2 ; the thickness of the hardened layer is 4 microns;

[0068] S2. Using a 200 mesh micro-embossed roll, an anti-glare coating solution is coated on the upper surface of the hardened layer, and an anti-glare layer is prepared after UV curing. The coating line speed is 6 m / min, and the UV curing energy is 250 mJ / cm 2 ; the anti-glare coating solution contains 10% by mass of micron-sized silica particles, and the specific formula of the anti-glare coating solution is the same as the anti-glare coating solution in Example 1 of Patent CN116693912A. The thickness of the anti-glare layer is 4 microns.

[0069] S3. Starting from the upper surface of the anti-glare layer, use the magnetron sputtering process to alternately stack M first refractive index layers and M second refractive index layers in sequence to prepare a wide-angle optical anti-reflection layer. The magnetron sputtering process parameters are: working pressure 0.15 - 0.6 Pa, coating speed 0.5 - 2 m / min; M = 2, 3 or 4;

[0070] S4. Using perfluoropolyether as the raw material, use the organic evaporation coating process to prepare an anti-fingerprint layer (refractive index n = 1.40 at a wavelength of 550 nm) on the upper surface of the wide-angle optical anti-reflection layer. The organic evaporation coating process parameters are: working pressure 5×10 -3 Pa, liquid flow rate 0.5 mL / min, evaporation temperature 320 °C; the thickness of the anti-fingerprint layer is 8 nm;

[0071] S5. Use a 150-mesh micro-embossing roller to coat transparent polyurethane on the lower surface of the transparent substrate, and prepare an impact-resistant layer after thermal curing. The coating line speed is 5 m / min, and the thermal curing temperature is 110 °C; the thickness of the impact-resistant layer is 150 microns;

[0072] S6. Use a 150-mesh micro-embossing roller to coat acrylic resin on the lower surface of the impact-resistant layer, and prepare a pressure-sensitive adhesive layer after thermal curing to finally obtain an optical film. The coating line speed is 5 m / min, and the thermal curing temperature is 110 °C. The thickness of the pressure-sensitive adhesive layer is 50 microns.

[0073] Example 1

[0074] On the above basis, the wide-angle optical anti-reflection layer in this example has a 4-layer structure, that is, M = 2. Starting from the side close to the transparent substrate, the first refractive index layer and the second refractive index layer are stacked in sequence. Among them, the material of the first refractive index layer is Nb2O5 (n = 2.35); the material of the second refractive index layer is SiO2 ((n = 1.46); it should be noted that the refractive index mentioned here refers to the refractive index at a wavelength of 550 nm. Starting from the side close to the transparent substrate, the thicknesses of the 4-layer structure in the wide-angle optical anti-reflection layer are 9 nm, 34 nm, 111 nm, and 79 nm in sequence. The magnetron sputtering process parameters are: working pressure 0.3 Pa, coating speed 1 m / min.

[0075] Perform reflectivity tests on the optical film of this example. The test results show that the reflectivity at 550 nm is 0.1%, the average reflectivity from 420 - 680 nm is 0.16%, the average reflectivity from 400 - 700 nm is 0.23%; the average reflectivity from 380 - 780 nm is 0.83%. Under the condition of 0° incident light: a* = 0.2, b* = 0.4; under the condition of 30° incident light: a* = 2.8, b* = 1.1; under the condition of 45° incident light: a* = 6.4, b* = 1.8.

[0076] Among them, a* and b* represent the optical visual effects of the antireflection film layer. The closer the values of the two are to zero, the better the integrated black effect. The larger the positive value of a*, the redder the reflected color of the film; the larger the negative value of a*, the greener the reflected color of the film. The larger the positive value of b*, the yellower the reflected color of the film; the larger the negative value of b*, the bluer the reflected color of the film. The same applies hereinafter.

[0077] Example 2

[0078] On the basis of the above, the wide-angle optical antireflection layer in this example has a 6-layer structure, that is, M = 3. Starting from the side close to the transparent substrate, the first refractive index material and the second refractive index material are stacked in sequence. Among them, the material of the first refractive index layer is Nb2O5 (n = 2.35); the material of the second refractive index layer is SiO2 ((n = 1.46); it should be noted that the refractive index mentioned here refers to the refractive index at a wavelength of 550 nm. Starting from the side close to the transparent substrate, the thicknesses of the 6-layer structure in the wide-angle optical antireflection layer are 6 nm, 48 nm, 21 nm, 45 nm, 19 nm, and 103 nm in sequence, and the magnetron sputtering process parameters are: working pressure 0.3 Pa, coating speed 1 m / min.

[0079] The reflectivity of the optical film in this example was tested. The test results show that the reflectivity at 550 nm is 1.1%, the average reflectivity from 420 - 680 nm is 0.60%, the average reflectivity from 400 - 700 nm is 0.59%; the average reflectivity from 380 - 780 nm is 0.59%. Under the condition of 0° incident light: a* = 0.9, b* = 1.6; under the condition of 30° incident light: a* = -0.6, b* = 3.4; under the condition of 45° incident light: a* = 0.4, b* = 3.2.

[0080] Example 3

[0081] On the basis of the above, the wide-angle optical antireflection layer in this example has an 8-layer structure, that is, M = 4. Starting from the side close to the transparent substrate, the materials of the first refractive index layer and the second refractive index layer are stacked in sequence. Among them, the material of the first refractive index layer is Nb2O5 (n = 2.35); the material of the second refractive index layer is SiO2 ((n = 1.46); it should be noted that the refractive index mentioned here refers to the refractive index at a wavelength of 550 nm. Starting from the side close to the transparent substrate, the thicknesses of the 8-layer structure in the wide-angle optical antireflection layer are 6 nm, 41 nm, 25 nm, 19 nm, 70 nm, 11 nm, 30 nm, and 84 nm in sequence, and the magnetron sputtering process parameters are: working pressure 0.3 Pa, coating speed 1 m / min.

[0082] The reflectivity of the optical film of this embodiment was tested. The test results show that the reflectivity at 550 nm is 0.3%, the average reflectivity from 420 - 680 nm is 0.37%, the average reflectivity from 400 - 700 nm is 0.39%, and the average reflectivity from 380 - 780 nm is 0.46%. Under the condition of 0° incident light: a* = 1.1, b* = 1.3; under the condition of 30° incident light: a* = 2.5, b* = 4.5; under the condition of 45° incident light: a* = 2.5, b* = 9.5.

[0083] The test results of the thickness and reflectivity of the wide - angle optical antireflection layer structures in Examples 1 to 3 are as Figure 4 shown, Figure 4 The unit of thickness in Figure 5 is nm; the test results of the core evaluation indicators of the integrated black are as

[0084] shown. For the wet process Figure 5 Among them, for the convenience of explaining the present invention, the wide - angle optical antireflection layer structure prepared by the wet process was compared with the examples. As shown in

[0085] it, two wide - angle optical antireflection layer structures based on the wet process are provided. (1) Single - layer structure: Prepared by a coating process using a low - refractive - index optical coating solution, with a thickness of 100 nm; (2) Two - layer structure: A high - refractive - index coating with a thickness of 100 nm is prepared on the surface of the antiglare layer by a coating process using a high - refractive - index optical coating solution, and then a low - refractive - index coating with a thickness of 100 nm is prepared on the surface of the high - refractive - index coating by a coating process using a low - refractive - index optical coating solution.

[0086] The formulation of the high - refractive - index optical coating solution is the same as that of the high - refractive - index optical coating solution in Example 1 of Patent CN116904116B.

[0087] The formulation of the low - refractive - index optical coating solution is the same as that in Example 2 of Patent CN117700794A.

[0087] The wet process refers to the preparation of a nano - scale film layer through a precision coating process. The whole process is carried out in an atmospheric environment and involves solvents. The dry process (magnetron sputtering process) is adopted in the examples, with more excellent optical antireflection effect and more uniform hue.

[0088] Figure 6 It is the comparison result of the reflectivity curves of the dry process and the wet process. Figure 6It can be seen that for the wide-angle antireflection layer structures (4 layers, 6 layers, 8 layers) adopted in the embodiments, the average reflection values in the entire visible light band of 380 - 780 nm are 0.83%, 0.59%, and 0.46% respectively, which are much lower than 2.32% and 1.65% of the single-layer and two-layer structures by the wet process. Similarly, for the band of 400 - 700 nm, the average reflectance of the wide-angle antireflection layer structures (4 layers, 6 layers, 8 layers) in the embodiments are 0.23%, 0.59%, and 0.39% respectively, which are also much lower than 2.20% and 1.22% of the single-layer and two-layer structures by the wet process. Similarly, for the band of 420 - 680 nm, the average reflectance of the wide-angle antireflection layer structures (4 layers, 6 layers, 8 layers) in the embodiments are 0.16%, 0.60%, and 0.37% respectively, which are also better than 2.12% and 1.05% of the single-layer and two-layer structures by the wet process.

[0089] Particularly, for the single-point reflection values at the 550 nm band which is the most sensitive to the human eye, the reflectance of the wide-angle antireflection layer structures (4 layers, 6 layers, 8 layers) adopted in the embodiments are 0.1%, 1.1%, and 0.3% respectively, which are much lower than 1.78% and 0.60% of the single-layer and two-layer structures by the wet process. Moreover, as the number of layers of the antireflection structure increases, the reflectance curve gradually becomes flatter, and the advantage is that the optical effect shows better, and there is no serious color deviation phenomenon even at a large viewing angle. Comparing at a large viewing angle of 45°, the a* and b* values of the wide-angle antireflection layer structures (4 layers, 6 layers, 8 layers) adopted in the embodiments are (6.4, 1.8), (0.4, 3.2), and (2.5, 9.5) respectively, which are much better than the color deviation values of (18, -23) and (26, -34) of the single-layer and two-layer structures by the wet process.

[0090] Although the embodiments of the present invention have been disclosed as above, it is not limited to only the applications listed in the specification and embodiments. It can be fully applied to various fields suitable for the present invention. For those familiar with the field, additional modifications can be easily made. Therefore, without departing from the general concept defined by the claims and the equivalent scope, the present invention is not limited to specific details.

Claims

1. A multifunctional integrated display black optical film, characterized in that, It includes a pressure-sensitive adhesive layer, an impact-resistant layer, a transparent substrate, a hardening layer, an anti-glare layer, a wide-angle optical anti-reflection layer, and an anti-fingerprint layer that are sequentially stacked.

2. The multifunctional integrated black optical film according to claim 1, wherein The pressure-sensitive adhesive layer is prepared from an acrylic resin through a coating process.

3. The multifunctional integrated black optical film according to claim 1, wherein The impact-resistant layer is prepared from a transparent polyurethane through a coating process.

4. The multifunctional integrated display black optical film according to claim 1, wherein The transparent substrate is a coil composed of a mixture of one or more of the following materials: polyethylene naphthalate, polyethylene terephthalate, triacetate cellulose, cycloolefin copolymer, cycloolefin polymer, polycarbonate. The thickness of the transparent substrate is 0.023 mm to 2 mm.

5. The multifunctional integrated black optical film according to claim 1, wherein The hardening layer is prepared from a hexa-functional polyurethane acrylate resin oligomer through a coating process.

6. The multifunctional integrated black optical film according to claim 1, characterized in that, The anti-glare layer is prepared from an anti-glare coating solution through a coating process. The anti-glare coating solution contains micron-sized silica particles with a mass ratio of 0.1 - 1%.

7. The multifunctional integrated display black optical film according to claim 1, characterized in that, The wide-angle optical anti-reflection layer is formed by sequentially and alternately stacking M first refractive index layers and M second refractive index layers starting from the side close to the transparent substrate, where M = 2, 3, or 4. Both the first refractive index layer and the second refractive index layer are prepared through a magnetron sputtering process. The material of the first refractive index layer is Nb2O5, and the second refractive index material is SiO2.

8. The multifunctional integrated display black optical film according to claim 1, characterized in that, The anti-fingerprint layer is prepared from perfluoropolyether through an organic vapor deposition process.

9. A method for preparing a multifunctional integrated black optical film as described in any one of claims 1-8, characterized in that, It includes the following steps: S1. Coat a hexa-functional polyurethane acrylate resin oligomer on the upper surface of the transparent substrate, and prepare the hardening layer after UV curing. S2. Coat the anti-glare coating solution on the upper surface of the hardening layer, and prepare the anti-glare layer after UV curing. S3. Use the magnetron sputtering process to sequentially and alternately stack M first refractive index layers and M second refractive index layers starting from the upper surface of the anti-glare layer to prepare the wide-angle optical anti-reflection layer. S4. Use perfluoropolyether as the raw material and adopt the organic vapor deposition process to prepare the anti-fingerprint layer on the upper surface of the wide-angle optical anti-reflection layer. S5. Coat the transparent polyurethane on the lower surface of the transparent substrate and prepare the impact-resistant layer after thermal curing. S6. Coat the acrylic resin on the lower surface of the impact-resistant layer and prepare the pressure-sensitive adhesive layer after thermal curing to finally obtain the optical film.

10. The preparation method of the multifunctional display integrated black optical film according to claim 9, characterized in that, It includes the following steps: S1. Use a 150 - 250 mesh micro - embossed roll to coat a hexa - functional polyurethane acrylate resin oligomer on the upper surface of the transparent substrate. After UV curing, a hardened layer is prepared. The coating line speed is 3 - 10 m / min, and the UV curing energy is 100 - 400 mJ / cm 2 ; S2. Use a 150 - 250 mesh micro - concave roller to coat an anti - glare coating liquid on the upper surface of the hardened layer, and prepare an anti - glare layer after UV curing. The coating line speed is 3 - 10 m / min, and the UV curing energy is 100 - 400 mJ / cm 2 ; S3. Use the magnetron sputtering process to sequentially and alternately stack M first refractive index layers and M second refractive index layers starting from the upper surface of the anti-glare layer to prepare the wide-angle optical anti-reflection layer. The parameters of the magnetron sputtering process are: working pressure 0.15 - 0.6 Pa, coating running speed 0.5 - 2 m / min; M = 2, 3, or 4. S4. Using perfluoropolyether as the raw material, an anti-fingerprint layer is prepared and formed on the upper surface of the wide-angle optical antireflection layer by an organic vapor deposition process. The parameters of the organic vapor deposition process are: working pressure 2.5 - 10×10 -3 Pa, liquid flow rate 0.25 - 1 mL / min, evaporation temperature 300 - 350 °C; S5. Use a 150 - 200 - mesh micro - concave roller to coat the transparent polyurethane on the lower surface of the transparent substrate and prepare the impact-resistant layer after thermal curing. The coating line speed is 3 - 10 m / min, and the thermal curing temperature is 90 - 120 °C. S6. Use a 150 - 200 - mesh micro - concave roller to coat the acrylic resin on the lower surface of the impact-resistant layer and prepare the pressure-sensitive adhesive layer after thermal curing to finally obtain the optical film. The coating line speed is 3 - 10 m / min, and the thermal curing temperature is 90 - 120 °C.

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