Reflecting film and preparation method and application thereof

Abstract

The invention discloses a reflecting film and a preparation method and application thereof, and belongs to the technical field of optical reflecting films. The reflecting film comprises a base film and a coating arranged on the surface of the base film, the coating contains a modified tetraaza metalloporphyrin compound; the modified tetraaza-metalloporphyrin compound has a core-shell structure, the core is tetraaza-metalloporphyrin, and the shell is a zeolite imidazate framework; the chemical formula of the tetraaza metalloporphyrin is # imgabs0 #; r1-R8 independently comprise a hydrogen atom, a halogen element, a branched chain or cyclic aliphatic hydrocarbon group with 3-10 carbon atoms, an aromatic hydrocarbon group, a hydroxyl group, a sulfo group or an amino group; m is a divalent metal ion; the zeolite imidazate framework contains Zn < 2 + > used for being in coordination binding with N in the tetraaza-metalloporphyrin. The reflective film is resistant to illumination and has a wide color gamut. The reflective film can be further used in a display device.

Description

Technical Field

[0001] The present invention relates to the technical field of optical reflective films, and in particular to a reflective film and a preparation method and application thereof. Background Art

[0002] Currently, white light-emitting diodes (WLEDs) are commonly used as light sources for display lighting devices. These solutions combine blue LEDs with yellow phosphors, or mix blue LEDs with green and red phosphors. However, these solutions suffer from the problem of the phosphors' broad emission peaks, resulting in a high-intensity yellow tint in the 590nm region of the modulated white light, affecting color purity.

[0003] As display technology matures, major manufacturers are increasingly pursuing improved color reproduction capabilities in their displays. From the first generation of sRGB to the current mainstream DCI P3, color gamuts are constantly improving. However, insufficient color purity has always been a major factor restricting the improvement of display color gamuts.

[0004] Some technologies have adopted quantum dots to improve the brightness and color gamut of displays, but these quantum dots often contain toxic heavy metals such as Cd or Pb, and have extremely poor water and oxygen stability, requiring high packaging technology, which greatly increases the cost of display devices.

[0005] In view of this, the present invention is proposed. Summary of the Invention

[0006] The object of the present invention is to provide a reflective film and a preparation method and application thereof, so as to solve or improve the above-mentioned technical problems.

[0007] The present invention can be achieved like this: In a first aspect, the present invention provides a reflective film, comprising a base film and a coating disposed on a surface of the base film; The coating contains a modified tetraazametalloporphyrin compound; A modified tetraazametalloporphyrin compound having a core-shell structure, wherein the core is tetraazametalloporphyrin and the shell is a zeolite imidazole ester framework; The chemical formula of tetraazametalloporphyrin is: ; wherein R1 to R8 independently include: a hydrogen atom, a halogen element, a branched or cyclic aliphatic hydrocarbon group having 3 to 10 carbon atoms, an aromatic hydrocarbon group, a hydroxyl group, a sulfonic acid group or an amino group; M is a divalent metal ion; The zeolitic imidazolate framework contains Zn for coordination with the nitrogen in the tetraazametalloporphyrin. 2+ .

[0008] In an alternative embodiment, M comprises Cu 2+ 、Zn2+ 、Co 2+ Mg 2+ 、Be 2+ , Pb 2+ 、Sn 2+ 、Ba 2+ or Fe 2+ .

[0009] In an optional embodiment, the preparation method of the modified tetraazaporphyrin compound comprises the following steps: mixing a tetraazaporphyrin colloidal solution with zinc acetate to form a pre-coordination complex; adding a 2-methylimidazole dispersion dropwise to the pre-coordination complex to carry out a coordination reaction to form a shell, and drying to obtain a modified tetraazaporphyrin compound.

[0010] In an optional embodiment, the preparation of the modified tetraazametalloporphyrin compound includes at least one of the following features: Feature 1: Tetraazametalloporphyrin colloidal solution and Zn in zinc acetate 2+ The molar ratio is 1:18 to 1:22; Feature 2: The 2-methylimidazole dispersion comprises 2-methylimidazole and N,N-dimethylformamide in a mass ratio of 0.8:100 to 1.2:100; Feature 3: The volume ratio of the 2-methylimidazole dispersion to the pre-coordinated complex is 1.8:1 to 2.2:1; Feature 4: The drop rate of the 2-methylimidazole dispersion is 0.45 L / min~0.55 L / min; Feature 5: The dropping temperature is 20℃~30℃, and the dropping time is 6h~24h.

[0011] In an optional embodiment, the preparation of the metalloporphyrin colloidal solution comprises: dispersing the metalloporphyrin in a solvent, and subjecting the solution to ultrasonic treatment in an ice bath to form a colloid.

[0012] In an optional embodiment, the mass ratio of the tetraazametalloporphyrin to the solvent is 2.5:1 to 3.5:1; optionally, the solvent includes N,N-dimethylformamide (DMF).

[0013] In an optional embodiment, the frequency of the ultrasonic treatment is 35 kHz to 45 kHz, and the time of the ultrasonic treatment is 25 min to 35 min.

[0014] In an optional embodiment, the preparation of the tetraazametalloporphyrin comprises: dissolving phthalonitrile and metal chloride in a mixed solvent and refluxing under a protective atmosphere; Wherein, the metal chloride is the chloride of the element M in the chemical formula of the tetraazametalloporphyrin; and / or, the molar ratio of phthalonitrile to metal chloride is 3.5:1 to 4.5:1; and / or, the mixed solvent comprises 1,8-diazabicycloundec-7-ene and 1-pentanol in a volume ratio of 1:2.5 to 1:3.5; And / or, the reflux temperature is 155° C. to 165° C., and the reflux time is 4 h to 8 h.

[0015] In an optional embodiment, the coating further contains an adhesive; optionally, the refractive index of the adhesive is 1.43~1.53; optionally, the adhesive includes at least one of thermosetting acrylic glue, polyurethane resin, epoxy resin and polyvinyl acetal resin.

[0016] In an optional embodiment, the coating further contains organic coating particles; optionally, the particle size of the organic coating particles is 30 μm to 60 μm; optionally, the organic coating particles include at least one of PMMA particles, PBMA particles, PET particles and PA particles.

[0017] In an optional embodiment, the coating contains an additive; optionally, the additive includes at least one of a dispersant, a curing agent and an antistatic agent; optionally, the dispersant includes at least one of a polyurethane dispersant, a polyacrylate, a modified polyacrylate dispersant and a polyester dispersant; optionally, the antistatic agent includes at least one of a fatty alcohol phosphate antistatic agent, an alkyl phosphate antistatic agent and a fatty alcohol polyoxyethylene ether antistatic agent; optionally, the curing agent includes an isocyanate curing agent.

[0018] In a second aspect, the present invention provides a method for preparing a reflective film according to the aforementioned embodiment, comprising the following steps: preparing a coating on the surface of a base film.

[0019] In an optional embodiment, when the coating contains a modified tetraazametalloporphyrin compound, organic coating particles, an adhesive and an additive, the preparation of the coating includes the following steps: mixing the adhesive, organic coating particles, additives and a fatty acid ester solvent to obtain a first coating liquid; adding a dispersion of the modified tetraazametalloporphyrin compound to the first coating liquid, and ultrasonicating to obtain a final coating liquid; coating the final coating liquid on the surface of the base film, and thermally curing.

[0020] In an optional embodiment, the final coating solution contains 1 ppm to 20 ppm of the modified tetraazametalloporphyrin compound.

[0021] In an alternative embodiment, the reflectivity of the base film is >96%.

[0022] In an alternative embodiment, the base film includes at least one of foamed polyethylene terephthalate, polypropylene, and polycarbonate.

[0023] In an optional embodiment, the thermal curing temperature is 115° C. to 125° C., and the thermal curing time is 1 min to 3 min.

[0024] In an optional embodiment, the mass ratio of the adhesive, the organic coating particles, the auxiliary agent and the fatty acid ester solvent is 8:1:0.5:6 to 12:1:1.5:10.

[0025] In an optional embodiment, the mass percentage of the modified tetraazametalloporphyrin compound in the modified tetraazametalloporphyrin compound dispersion is 0.05% to 0.2%.

[0026] In an optional embodiment, the mass ratio of the first coating liquid to the dispersion of the modified tetraazametalloporphyrin compound is 1:1000 to 4:1000.

[0027] In an optional embodiment, the ultrasonic frequency is 35kHz~45kHz, and the ultrasonic time is 15min~25min.

[0028] In a third aspect, the present invention provides a display device comprising the reflective film according to the aforementioned embodiment.

[0029] The beneficial effects of the present invention include: The present invention proposes for the first time a reflective film containing a modified tetraazametalloporphyrin compound. The modified tetraazametalloporphyrin compound has a core-shell structure, wherein the core is the tetraazametalloporphyrin and the shell is a zeolite imidazolate framework. The chemical formula of the tetraazametalloporphyrin is: Wherein, R1 to R8 independently include: hydrogen atom, halogen element, branched or cyclic aliphatic hydrocarbon group with 3 to 10 carbon atoms, aromatic hydrocarbon group, hydroxyl group, sulfonic acid group or amino group; M is a divalent metal ion; the zeolite imidazolate framework contains Zn for coordinating with N in tetraazametalloporphyrin. 2+ .

[0030] This modified tetraazaporphyrin compound can absorb 580nm to 640nm stray light from backlight sources, improving its color purity. By using this modified tetraazaporphyrin compound to form a reflective film, the film can be made light-resistant and have a wide color gamut. This reflective film can be further used in display devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the embodiments. It should be understood that the following drawings only illustrate certain embodiments of the present invention and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other relevant drawings can be obtained based on these drawings without paying any creative work.

[0032] Figure 1 A schematic structural diagram of the reflective film provided by the present invention; Figure 2 TEM image of the sample tested by transmission electron microscopy in Experimental Example 1; Figure 3 The SEM image and EDS spectrum of CuTAP@ZIF-8 in Experimental Example 1; Figure 4 This is the reflectivity curve of the reflective film prepared in Example 4 in Experimental Example 2.

[0033] Icons: 10-base film; 20-coating; 21-adhesive; 22-modified tetraazametalloporphyrin compound; 23-organic coated particles. DETAILED DESCRIPTION

[0034] To make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention are described clearly and completely below. Where specific conditions are not specified in the embodiments, conventional conditions or conditions recommended by the manufacturer are used. Where the manufacturer of the reagents or instruments is not specified, all are conventional products that can be purchased commercially.

[0035] The reflective film provided by the present invention and its preparation method and application are described in detail below.

[0036] The present invention provides a modified tetraazametalloporphyrin compound 22 (combined with Figure 1 ), the modified tetraazametalloporphyrin compound 22 has a core-shell structure, wherein the core is tetraazametalloporphyrin and the shell is a zeolite imidazole ester framework.

[0037] The chemical formula of tetraazametalloporphyrin is: Wherein, R1-R8 independently include: a hydrogen atom, a halogen element, a branched or cyclic aliphatic hydrocarbon group having 3 to 10 carbon atoms, an aromatic hydrocarbon group, a hydroxyl group (-OH), a sulfonic acid group (-SH), or an amino group (-NH). The halogen element may illustratively include F, Cl, or Br.

[0038] M is a divalent metal ion, and for example, M may include Cu 2+ 、Zn 2+ 、Co 2+ Mg 2+ 、Be 2+ , Pb 2+ 、Sn 2+ 、Ba 2+ or Fe 2+ wait.

[0039] The zeolitic imidazolate framework contains Zn for coordination with the nitrogen in the tetraazametalloporphyrin.2+ .

[0040] The modified tetraazametalloporphyrin compound 22 provided by the present invention is designated MTAP@ZIF-8. The core is designated MTAP (tetraazametalloporphyrin). A zeolite imidazolate framework is grown on the surface of the core, improving MTAP's photostability. This modified tetraazametalloporphyrin compound 22 can absorb stray light from backlight sources in the 580-640 nm wavelength range, improving its color purity.

[0041] Accordingly, the present invention also provides a method for preparing the modified tetraazametalloporphyrin compound 22, which may include the following steps: S1: The tetraazametalloporphyrin colloidal solution is mixed with zinc acetate to form a pre-coordinated complex.

[0042] In some optional embodiments, the tetraazametalloporphyrin colloidal solution and the Zn in zinc acetate 2+ The molar ratio of the tetraazaporphyrin colloid solution to the zinc acetate is 1:18 to 1:22, such as 1:18, 1:19, 1:20, 1:21 or 1:22, or other values ​​within the range of 1:18 to 1:22. 2+ The molar ratio of the tetraazaporphyrin colloidal solution and the zinc acetate can be 1:20. The mixing time of the above-mentioned zinc acetate can be 30 minutes. The zinc acetate is Zn(OAc)2.

[0043] In some optional embodiments, the preparation of the metalloporphyrin colloid solution may include: dispersing the metalloporphyrin in a solvent, and ultrasonically treating the solvent in an ice bath to form a colloid.

[0044] The mass ratio of the tetraazametalloporphyrin to the solvent may be 2.5:1 to 3.5:1, such as 2.5:1, 2.8:1, 3:1, 3.2:1, or 3.5:1, or other values ​​within the range of 2.5:1 to 3.5:1. The solvent may illustratively include N,N-dimethylformamide (DMF).

[0045] The frequency of the ultrasonic treatment can be 35 kHz to 45 kHz, such as 35 kHz, 38 kHz, 40 kHz, 42 kHz, or 45 kHz, or other values ​​within the range of 35 kHz to 45 kHz. The duration of the ultrasonic treatment can be 25 min to 35 min, such as 25 min, 28 min, 30 min, 32 min, or 35 min, or other values ​​within the range of 25 min to 35 min.

[0046] A uniform colloid was obtained by ultrasonic treatment under the above ice bath conditions, and then undispersed particles were filtered out through a filter membrane (pore size of 0.22 μm) to obtain a uniformly dispersed MTAP colloidal solution.

[0047] In some optional embodiments, the preparation of the metallotetraazaporphyrin (MTAP) may include: dissolving phthalonitrile and metal chloride in a mixed solvent, and refluxing under a protective atmosphere (such as nitrogen atmosphere).

[0048] The metal chloride is the chloride of the element M in the chemical formula of the tetraazametalloporphyrin.

[0049] The molar ratio of phthalonitrile to metal chloride can be 3.5:1 to 4.5:1, such as 3.5:1, 3.8:1, 4:1, 4.2:1 or 4.5:1, or other values ​​within the range of 3.5:1 to 4.5:1. In some typical embodiments, the molar ratio of phthalonitrile to metal chloride is 4:1.

[0050] The mixed solvent may include 1,8-diazabicycloundec-7-ene (DBU) and 1-pentanol in a volume ratio of 1:2.5 to 1:3.5 (e.g., 1:2.5, 1:2.8, 1:3, 1:3.2, or 1:3.5). In some typical embodiments, the mixed solvent is obtained by mixing DBU and 1-pentanol in a volume ratio of 1:3.

[0051] In some optional embodiments, the reflux temperature may be 155°C to 165°C, such as 155°C, 158°C, 160°C, 162°C or 165°C, or other values ​​within the range of 155°C to 165°C.

[0052] The reflux time may be 4 hours to 8 hours, such as 4 hours, 5 hours, 6 hours, 7 hours or 8 hours, or other values ​​within the range of 4 hours to 8 hours.

[0053] Furthermore, the crude product obtained by reflux is rapidly cooled in an ice bath and then centrifuged. The precipitate is washed with ethanol and deionized water in sequence and dried in vacuo to obtain the tetraazametalloporphyrin.

[0054] S2: Add the 2-methylimidazole dispersion dropwise to the pre-coordinated complex to carry out coordination reaction to form a shell, and dry to obtain the modified tetraazametalloporphyrin compound 22.

[0055] In some optional embodiments, the 2-methylimidazole dispersion (2-MIM) may include 2-methylimidazole and N,N-dimethylformamide in a mass ratio of 0.8:100 to 1.2:100. The mass ratio of 2-methylimidazole to N,N-dimethylformamide may be 0.8:100, 0.9:100, 1:100, 1.1:100, or 1.2:100, or other values ​​within the range of 0.8:100 to 1.2:100. In some typical embodiments, the 2-methylimidazole dispersion (2-MIM) includes 2-methylimidazole and N,N-dimethylformamide in a mass ratio of 1:100.

[0056] The above-mentioned dropping process is carried out under a protective atmosphere, and the protective atmosphere here can be an argon atmosphere.

[0057] In some optional embodiments, the volume ratio of the 2-methylimidazole dispersion to the pre-coordinated complex can be 1.8:1 to 2.2:1, such as 1.8:1, 1.9:1, 2:1, 2.1:1, or 2.2:1, or other values ​​within the range of 1.8:1 to 2.2:1. In some more typical embodiments, the volume ratio of the 2-methylimidazole dispersion to the pre-coordinated complex is 2:1.

[0058] In some optional embodiments, the dropping speed of the 2-methylimidazole dispersion can be 0.45 L / min~0.55 L / min, such as 0.45 L / min, 0.48 L / min, 0.5 L / min, 0.52 L / min or 0.55 L / min, or other values ​​within the range of 0.45 L / min~0.55 L / min.

[0059] If the dripping speed of the 2-methylimidazole dispersion is less than 0.45 L / min, it is easy to cause local concentration imbalance in the reaction system, causing defects such as proliferation of free crystal nuclei, loose shell layer and even core-shell separation; if the dripping speed of the 2-methylimidazole dispersion is greater than 0.55 L / min, it is easy to cause incomplete reaction and uneven shell layer.

[0060] In some optional embodiments, the dropwise addition temperature may be 20° C. to 30° C., such as 20° C., 22° C., 25° C., 28° C., or 30° C., or other values ​​within the range of 20° C. to 30° C. The dropwise addition time may be 6 h to 24 h, such as 6 h, 10 h, 14 h, 18 h, 22 h, or 24 h, or other values ​​within the range of 6 h to 24 h.

[0061] If the addition time is shorter than 6 hours, the shell thickness will be too thin and the shell will not fully cover the core. If the addition time is longer than 24 hours, the shell will be too thick and the grain size will be too large, affecting the luminescence performance.

[0062] After the addition was completed, liquid nitrogen was added to quench the reaction.

[0063] Furthermore, the preparation of the reflective film may also include a post-processing process, which can also be understood as a purification process.

[0064] In some optional embodiments, the purification process may include: centrifuging the MTAP@ZIF-8 reaction solution obtained by the S2 reaction (the centrifugal speed can be, for example, 8000 rpm, and the centrifugal time can be, for example, 15 min), washing the precipitate (the washing solution used for washing can be, for example, methanol, and the number of washing times can be, for example, 3 times), soaking in methanol after washing to completely remove DMF (the soaking time can be, for example, 24 h), and then drying (the drying temperature can be, for example, 120°C).

[0065] In situ synthesis was used to grow a ZIF-8 shell on the surface of MTAP whose molecular skeleton is a macrocyclic organic molecular structure (Zn 2+ Coordinated with the N atoms in MTAP), it can inhibit photobleaching and improve light stability, which is conducive to the stable operation of the reflective film under long-term light conditions.

[0066] In addition, the present invention also provides a reflective film, such as Figure 1 As shown, the reflective film includes a base film 10 and a coating layer 20 disposed on the surface of the base film 10. The coating layer 20 contains a modified tetraazametalloporphyrin compound 22, organic coating particles 23 and an adhesive 21.

[0067] In some optional embodiments, the base film 10 is a white reflective base film 10 with a reflectivity greater than 96%. The base film 10 may illustratively include at least one of foamed polyethylene terephthalate (PET), polypropylene (PP), and polycarbonate (PC).

[0068] The coating layer 20 contains the modified tetraazametalloporphyrin compound 22 .

[0069] In some optional embodiments, the coating 20 further comprises an adhesive 21. The refractive index of the adhesive 21 may be 1.43 to 1.53, such as 1.43, 1.45, 1.47, 1.5, or 1.53, or may be other values ​​within the range of 1.43 to 1.53. For example, the adhesive 21 may include, but is not limited to, at least one of thermosetting acrylic glue, polyurethane resin, epoxy resin, and polyvinyl acetal resin.

[0070] In some optional embodiments, the coating layer 20 further comprises organic coating particles 23. The particle size of the organic coating particles 23 may be 30 μm to 60 μm, such as 30 μm, 35 μm, 40 μm, 45 μm, 50 μm, 55 μm or 60 μm, or other values ​​within the range of 30 μm to 60 μm.

[0071] If the particle size of the organic coating particles 23 is less than 30 μm, the organic coating particles cannot fully support the LGP on the reflective film, which may easily cause scratches on the LGP. If the particle size of the organic coating particles 23 is greater than 60 μm, the thickness of the backlight module will increase, which is not in line with the development trend of thinner displays.

[0072] For example, the organic coating particles 23 may include, by way of example but not limitation, at least one of PMMA particles, PBMA particles, PET particles, and PA particles.

[0073] In some optional embodiments, the coating 20 further contains an auxiliary agent.

[0074] The auxiliary agent may include at least one of a dispersant, a curing agent, and an antistatic agent. The dispersant may, by way of example but not limitation, include at least one of a polyurethane dispersant, a polyacrylate dispersant, a modified polyacrylate dispersant, and a polyester dispersant. The antistatic agent may, by way of example but not limitation, include at least one of a fatty alcohol phosphate antistatic agent, an alkyl phosphate antistatic agent, and a fatty alcohol polyoxyethylene ether antistatic agent. The curing agent may, by way of example but not limitation, include an isocyanate curing agent.

[0075] As mentioned above, the organic coating particles 23 contained in the reflective film can improve the scratching and adsorption problems between the reflective film and the light guide plate, and the modified tetraazametalloporphyrin compound 22 contained in the reflective film can absorb 580nm~640nm mixed color light in the backlight source to improve its color purity.

[0076] Correspondingly, the present invention also provides a method for preparing the above-mentioned reflective film, comprising the following steps: preparing a coating layer 20 on the surface of the base film 10 .

[0077] When the coating 20 contains a modified tetraazametalloporphyrin compound 22, organic coating particles 23, an adhesive 21, and an additive, the preparation of the coating 20 may include the following steps: mixing the adhesive 21, the organic coating particles 23, the additive, and a fatty acid ester solvent to obtain a first coating liquid; adding a dispersion of the modified tetraazametalloporphyrin compound 22 to the first coating liquid, and ultrasonicating to obtain a final coating liquid; coating the final coating liquid on the surface of the base film 10, and thermally curing.

[0078] In some optional embodiments, the mass ratio of the adhesive 21, the organic-coated particles 23, the auxiliary agent, and the fatty acid ester solvent can be 8:1:0.5:6 to 12:1:1.5:10. In some more typical embodiments, the mass ratio of the adhesive 21, the organic-coated particles 23, the auxiliary agent, and the fatty acid ester solvent can be 10:1:1:8. The fatty acid ester solvent can include at least one of ethyl acetate and butyl acetate. For example, the fatty acid ester solvent can include ethyl acetate and butyl acetate in a mass ratio of 1:1.

[0079] In some optional embodiments, the mass percentage of the modified tetraazametalloporphyrin compound 22 in the modified tetraazametalloporphyrin compound 22 dispersion can be 0.05% to 0.2%, such as 0.05%, 0.1%, 0.15% or 0.2%, or other values ​​within the range of 0.05% to 0.2%.

[0080] In some optional embodiments, the mass ratio of the first coating liquid to the dispersion of the modified tetraazametalloporphyrin compound 22 can be 1:1000 to 4:1000, such as 1:1000, 1.5:1000, 2:1000, 2.5:1000, 3:1000, 3.5:1000 or 4:1000, or other values ​​within the range of 1:1000 to 4:1000.

[0081] If the mass ratio of the first coating liquid to the dispersion of the modified tetraazaporphyrin compound 22 is less than 1:1000 (such as 1:1000), it is not conducive to improving the color gamut of the reflective film; if the mass ratio of the first coating liquid to the dispersion of the modified tetraazaporphyrin compound 22 is greater than 4:1000 (such as 5:1000), it will affect the backlight brightness.

[0082] In some optional embodiments, the final coating liquid contains 1 ppm to 20 ppm of a modified tetraazaporphyrin compound. If the amount of the modified tetraazaporphyrin compound 22 in the final coating liquid is less than 1 ppm, it is not conducive to its absorption of stray light in the 580 nm to 640 nm band, resulting in a less significant color gamut enhancement effect. If the amount of the modified tetraazaporphyrin compound 22 in the final coating liquid is greater than 20 ppm, the reflective film absorbs too much backlight, resulting in a reduction in display brightness. Furthermore, the final coating liquid may contain 1 ppm to 5 ppm of the modified tetraazaporphyrin compound.

[0083] In addition, if the content of organic coating particles 23 in the final coating liquid is too low, an air barrier layer cannot be completely formed between the reflective film and the light guide plate (LGP) above it, which can easily scratch the light guide plate; if the content of organic coating particles 23 in the final coating liquid is too high, the glossiness of the reflective film is too low, reducing the backlight brightness.

[0084] In some optional embodiments, the ultrasonic frequency can be 35 kHz to 45 kHz, such as 35 kHz, 38 kHz, 40 kHz, 42 kHz, or 45 kHz, or other values ​​within the range of 35 kHz to 45 kHz. The ultrasonic time can be 15 min to 25 min, such as 15 min, 18 min, 20 min, 22 min, or 25 min, or other values ​​within the range of 15 min to 25 min.

[0085] In some optional embodiments, the thermal curing temperature may be 115°C to 125°C, such as 115°C, 118°C, 120°C, 122°C or 125°C, or other values ​​within the range of 115°C to 125°C.

[0086] The heat curing time may be 1 min to 3 min, such as 1 min, 1.5 min, 2 min, 2.5 min or 3 min, or other values ​​within the range of 1 min to 3 min.

[0087] In addition, the present invention also provides a display device comprising the above-mentioned reflective film.

[0088] As for the reflective film provided by the present invention, yellow light at 590 nm can be effectively absorbed by the reflective film, that is, the reflective film provided by the present invention can improve the color purity of the light source and increase the color gamut of the display device.

[0089] The features and performance of the present invention are further described in detail below with reference to the embodiments.

[0090] Example 1 This embodiment provides a modified tetraazametalloporphyrin compound 22, the preparation method of which comprises: S1: The tetraazametalloporphyrin colloidal solution is mixed with zinc acetate to form a pre-coordinated complex.

[0091] S11: Preparation of tetraazametalloporphyrin.

[0092] 4 mmol of o-phthalonitrile and 1 mmol of CuCl2 were dissolved in 20 mL of a mixed solvent (5 mL of DBU and 15 mL of 1-pentanol). Under nitrogen, the mixture was refluxed at 160°C for 6 hours to obtain a crude CuTAP product. The crude CuTAP product was rapidly cooled in an ice bath and then centrifuged. The precipitate was washed with 40 mL of ethanol, then 40 mL of deionized water, and dried under vacuum to obtain the tetraazametalloporphyrin (CuTAP).

[0093] S12: preparing a tetraazametalloporphyrin colloidal solution.

[0094] 15 mg of CuTAP was dispersed in 5 mL of anhydrous DMF and treated in a 40 kHz ultrasonic instrument under ice bath conditions for 30 min to form a uniform colloid. The undispersed particles were then filtered through a 0.22 μm filter membrane to obtain a uniformly dispersed CuTAP colloidal solution.

[0095] S13: preparing a pre-coordinated complex.

[0096] 60 mg Zn(OAc)2 was added to the above CuTAP colloidal solution and stirred for 30 min to form a pre-coordinated complex. 2+ The molar ratio is 1:20.

[0097] S2: adding the 2-methylimidazole dispersion dropwise to the pre-coordinated complex to carry out coordination reaction to form the shell, and drying to obtain the modified tetraazametalloporphyrin compound 22.

[0098] Specifically, 0.1 g of 2-methylimidazole (2-MIM) was dissolved in 10 g of anhydrous DMF to obtain a 2-MIM dispersion. Under an argon atmosphere at 25°C, the 2-MIM dispersion was added dropwise to the pre-coordinated complex at a rate of 0.5 L / min (the volume ratio of 2-MIM dispersion to pre-coordinated complex was 2:1). After reacting for 6 hours, the reaction was terminated by adding liquid nitrogen to obtain a CuTAP@ZIF-8 reaction solution.

[0099] S3: Post-processing.

[0100] The CuTAP@ZIF-8 reaction solution obtained in step S2 was centrifuged at 8000 rpm for 15 min, and the precipitate was washed three times with 10 mL of methanol each time, then soaked in methanol for 24 h to completely remove DMF, and then vacuum dried at 12 °C to obtain the modified tetraazametalloporphyrin compound 22 (CuTAP@ZIF-8).

[0101] Example 2 This embodiment provides a modified tetraazametalloporphyrin compound 22, the preparation method of which comprises: S1: The tetraazametalloporphyrin colloidal solution is mixed with zinc acetate to form a pre-coordinated complex.

[0102] S11: Preparation of tetraazametalloporphyrin.

[0103] 3.5 mmol of o-phthalonitrile and 1 mmol of CuCl2 were dissolved in 20 mL of a mixed solvent (5 mL of DBU and 12.5 mL of 1-pentanol). Under nitrogen, the mixture was refluxed at 155°C for 8 hours to obtain a crude CuTAP product. The crude CuTAP product was rapidly cooled in an ice bath and then centrifuged. The precipitate was washed sequentially with 40 mL of ethanol and 40 mL of deionized water, and dried under vacuum to obtain the tetraazametalloporphyrin (CuTAP).

[0104] S12: preparing a tetraazametalloporphyrin colloidal solution.

[0105] 12.5 mg of CuTAP was dispersed in 5 mL of anhydrous DMF and treated in a 35 kHz ultrasonic instrument under ice bath conditions for 35 min to form a uniform colloid. The undispersed particles were then filtered out through a 0.22 μm filter membrane to obtain a uniformly dispersed CuTAP colloidal solution.

[0106] S13: preparing a pre-coordinated complex.

[0107] Zn(OAc)2 was added to the above CuTAP colloidal solution to make CuTAP and Zn in Zn(OAc)2 2+ The molar ratio of MTAP to Zn(OAc)2 was 1:18, and the mixture was stirred for 30 min to form a pre-coordinated complex. 2+ The molar ratio is 1:20.

[0108] S2: adding the 2-methylimidazole dispersion dropwise to the pre-coordinated complex to carry out coordination reaction to form the shell, and drying to obtain the modified tetraazametalloporphyrin compound 22.

[0109] Specifically, 80 mg of 2-methylimidazole (2-MIM) was dissolved in 10,000 mg of anhydrous DMF to obtain a 2-MIM dispersion. Under an argon atmosphere and at a constant temperature of 25°C, the 2-MIM dispersion was added dropwise to the pre-coordinated complex at a rate of 0.45 L / min (the volume ratio of 2-MIM dispersion to pre-coordinated complex was 1.8:1). After reacting for 24 hours, the reaction was terminated by adding liquid nitrogen to obtain a CuTAP@ZIF-8 reaction solution.

[0110] S3: Post-processing.

[0111] The CuTAP@ZIF-8 reaction solution obtained in step S2 was centrifuged at 8000 rpm for 15 min, and the precipitate was washed three times with 10 mL of methanol each time, then soaked in methanol for 24 h to completely remove DMF, and then vacuum dried at 12 °C to obtain the modified tetraazametalloporphyrin compound 22 (CuTAP@ZIF-8).

[0112] Example 3 This embodiment provides a modified tetraazametalloporphyrin compound 22, the preparation method of which comprises: S1: The tetraazametalloporphyrin colloidal solution is mixed with zinc acetate to form a pre-coordinated complex.

[0113] S11: Preparation of tetraazametalloporphyrin.

[0114] 4.5 mmol of o-phthalonitrile and 1 mmol of CuCl2 were dissolved in 20 mL of a mixed solvent (5 mL of DBU and 17.5 mL of 1-pentanol). Under nitrogen, the mixture was refluxed at 165°C for 6 hours to obtain a crude CuTAP product. The crude CuTAP product was rapidly cooled in an ice bath and then centrifuged. The precipitate was washed with 40 mL of ethanol, then 40 mL of deionized water, and dried under vacuum to obtain the tetraazametalloporphyrin (CuTAP).

[0115] S12: preparing a tetraazametalloporphyrin colloidal solution.

[0116] 17.5 mg of CuTAP was dispersed in 5 mL of anhydrous DMF and treated in a 45 kHz ultrasonic instrument under ice bath conditions for 25 min to form a uniform colloid. The undispersed particles were then filtered out through a 0.22 μm filter membrane to obtain a uniformly dispersed CuTAP colloidal solution.

[0117] S13: preparing a pre-coordinated complex.

[0118] Zn(OAc)2 was added to the above CuTAP colloidal solution to make CuTAP and Zn in Zn(OAc)2 2+ The molar ratio of 1:22 was 1:22, and the mixture was stirred for 30 min to form a pre-coordinated complex.

[0119] S2: adding the 2-methylimidazole dispersion dropwise to the pre-coordinated complex to carry out coordination reaction to form the shell, and drying to obtain the modified tetraazametalloporphyrin compound 22.

[0120] Specifically, 120 mg of 2-methylimidazole (2-MIM) was dissolved in 10,000 mg of anhydrous DMF to obtain a 2-MIM dispersion. Under an argon atmosphere at 25°C, the 2-MIM dispersion was added dropwise to the pre-coordinated complex at a rate of 0.55 L / min (the volume ratio of 2-MIM dispersion to pre-coordinated complex was 2.2:1). After reacting for 12 hours, the reaction was terminated by adding liquid nitrogen to obtain a CuTAP@ZIF-8 reaction solution.

[0121] S3: Post-processing.

[0122] The CuTAP@ZIF-8 reaction solution obtained in step S2 was centrifuged at 8000 rpm for 15 min, and the precipitate was washed three times with 10 mL of methanol each time, then soaked in methanol for 24 h to completely remove DMF, and then vacuum dried at 12 °C to obtain the modified tetraazametalloporphyrin compound 22 (CuTAP@ZIF-8).

[0123] Example 4 This embodiment provides a reflective film, the preparation method of which includes: Step (1): Prepare the first coating solution.

[0124] 16 g of adhesive (polyurethane resin), 2 g of PET organic coating particles 23 (particle size 45 μm), 1 g of additives (a modified polyacrylate dispersant, a fatty alcohol polyoxyethylene ether antistatic agent, and an isocyanate curing agent in a mass ratio of approximately 1:5:45), 6 g of ethyl acetate, and 6 g of butyl acetate were weighed and uniformly mixed to obtain a first coating solution.

[0125] Step (2): Prepare the final coating solution.

[0126] 0.12 mg of the CuTAP@ZIF-8 powder prepared in Example 1 was weighed and dispersed in ethyl acetate to obtain a 0.1 wt% CuTAP@ZIF-8 dispersion. The CuTAP@ZIF-8 dispersion was added to the first coating solution (the mass ratio of the first coating solution to the CuTAP@ZIF-8 dispersion was 1:1000). The solution was then sonicated at 40 kHz for 20 minutes to obtain a final coating solution with a CuTAP@ZIF-8 concentration of 1 ppm.

[0127] Step (3): coating and drying.

[0128] The final coating liquid was evenly coated on the surface of a white reflective base film 10 (specifically, the base film 10 was a base film 10 with a thickness of 225 μm and a reflectivity of approximately 97% and model FDX225 produced by Ningbo Changyang Technology Co., Ltd., China) using an OSP-80 wire rod. The wet film thickness was 80 μm, and the film was then thermally cured at 120° C. for 2 minutes to obtain a reflective film having a coating layer 20.

[0129] Example 5 This embodiment provides a reflective film, the preparation method of which includes: Step (1): Prepare the first coating solution.

[0130] 24 g of adhesive (epoxy resin), 2 g of PET organic coating particles 23 (particle size 30 μm), 3 g of additives (polyurethane dispersant, fatty alcohol phosphate antistatic agent, and isocyanate curing agent in a mass ratio of approximately 1:6:40), 10 g of ethyl acetate, and 10 g of butyl acetate were weighed and uniformly mixed to obtain a first coating solution.

[0131] Step (2): Prepare the final coating solution.

[0132] 0.12 mg of the CuTAP@ZIF-8 powder prepared in Example 2 was weighed and dispersed in ethyl acetate to obtain a 0.05 wt% CuTAP@ZIF-8 dispersion. The CuTAP@ZIF-8 dispersion was added to the first coating solution (the mass ratio of the first coating solution to the CuTAP@ZIF-8 dispersion was 2:1000). The solution was then sonicated at 35 kHz for 25 minutes to obtain a final coating solution with a CuTAP@ZIF-8 concentration of 1 ppm.

[0133] Step (3): coating and drying.

[0134] The final coating liquid was evenly coated on the surface of a white reflective base film 10 (specifically, the base film 10 was a 225 μm thick base film 10 produced by Ningbo Changyang Technology Co., Ltd., China, with a reflectivity of approximately 97%) using an OSP-80 wire rod. The wet film thickness was 80 μm, and the film was then thermally cured at 115° C. for 3 minutes to obtain a reflective film having a coating layer 20.

[0135] Example 6 This embodiment provides a reflective film, the preparation method of which includes: Step (1): Prepare the first coating solution.

[0136] 20 g of acrylic glue, 2 g of PA organic coating particles 23 (particle size 60 μm), 2 g of additives (polyacrylate, alkyl phosphate antistatic agent, and isocyanate curing agent in a mass ratio of approximately 1:8:36), 8 g of ethyl acetate, and 8 g of butyl acetate were weighed and uniformly mixed to obtain a first coating solution.

[0137] Step (2): Prepare the final coating solution.

[0138] 0.12 mg of the CuTAP@ZIF-8 powder prepared in Example 3 was weighed and dispersed in ethyl acetate to obtain a 0.2 wt% CuTAP@ZIF-8 dispersion. The CuTAP@ZIF-8 dispersion was added to the first coating solution (the mass ratio of the first coating solution to the CuTAP@ZIF-8 dispersion was 1:1000). The solution was then sonicated at 45 kHz for 15 minutes to obtain a final coating solution with a CuTAP@ZIF-8 concentration of 1 ppm.

[0139] Step (3): coating and drying.

[0140] The final coating liquid was evenly coated on the surface of a white reflective base film 10 (specifically, the base film 10 was a 225 μm thick base film 10 produced by Ningbo Changyang Technology Co., Ltd., China, with a reflectivity of approximately 97%) using an OSP-80 wire rod. The wet film thickness was 80 μm, and the film was then thermally cured at 125° C. for 1 minute to obtain a reflective film having a coating layer 20.

[0141] Example 7 The difference between this embodiment and embodiment 4 is that the concentration of CuTAP@ZIF-8 in the final coating solution is 3 ppm.

[0142] Example 8 The difference between this embodiment and embodiment 4 is that the concentration of CuTAP@ZIF-8 in the final coating solution is 5 ppm.

[0143] Example 9 The difference between this embodiment and embodiment 4 is that the concentration of CuTAP@ZIF-8 in the final coating solution is 10 ppm.

[0144] Example 10 The difference between this embodiment and embodiment 4 is that the concentration of CuTAP@ZIF-8 in the final coating solution is 20 ppm.

[0145] Comparative Example 1 The difference between this comparative example and Example 4 is that the first coating liquid is directly coated on the surface of the base film 10. That is, the coating layer 20 does not contain CuTAP@ZIF-8.

[0146] Comparative Example 2 The difference between this comparative example and Example 4 is that an equal amount of CuTAP@ZIF-8 powder is replaced by CuTAP powder that is not coated with ZIF-8.

[0147] Comparative Example 3 The difference between this comparative example and Example 7 is that an equal amount of CuTAP@ZIF-8 powder is replaced by CuTAP powder that is not coated with ZIF-8.

[0148] Comparative Example 4 The difference between this comparative example and Example 8 is that an equal amount of CuTAP@ZIF-8 powder is replaced by CuTAP powder that is not coated with ZIF-8.

[0149] Comparative Example 5 The difference between this comparative example and Example 9 is that an equal amount of CuTAP@ZIF-8 powder is replaced by CuTAP powder that is not coated with ZIF-8.

[0150] Comparative Example 6 The difference between this comparative example and Example 10 is that an equal amount of CuTAP@ZIF-8 powder is replaced by CuTAP powder that is not coated with ZIF-8.

[0151] Comparative Example 7 The difference between this comparative example and Example 4 is that the concentration of CuTAP@ZIF-8 contained in the final coating solution is 0.3 ppm.

[0152] Comparative Example 8 The difference between this comparative example and Example 4 is that the dropping speed of the 2-methylimidazole dispersion is 0.3 L / min.

[0153] Comparative Example 9 The difference between this comparative example and Example 4 is that the dropping speed of the 2-methylimidazole dispersion is 0.8 L / min.

[0154] Comparative Example 10 The difference between this comparative example and Example 4 is that the concentration of CuTAP@ZIF-8 contained in the final coating solution is 30 ppm.

[0155] Comparative Example 11 The difference between this comparative example and Example 4 is that the concentration of CuTAP@ZIF-8 contained in the final coating solution is 50 ppm.

[0156] Test Example 1 The CuTAP@ZIF-8 prepared in Example 1 was dispersed in toluene to prepare a transmission electron microscope (TEM) test sample. The TEM image is shown in FIG. Figure 2 shown.

[0157] Depend on Figure 2 It can be seen that the CuTAP@ZIF-8 crystal has an obvious core-shell structure, indicating that the ZIF-8 shell has been successfully grown on the CuTAP surface.

[0158] In addition, the CuTAP@ZIF-8 prepared in Example 1 was observed by scanning electron microscopy and energy spectrum detection. Figure 3As shown in (a), the EDS spectrum is as follows Figure 3 As shown in (b) and (c), Figure 3 (b) and (c) are the energy spectrum results of Cu and Zn corresponding to the dotted box in (a). Figure 3 It can be seen that Cu and Zn elements can be detected in the above samples, further confirming the successful growth of the ZIF-8 shell.

[0159] Test Example 2 The reflectivity test of the reflective film prepared in Example 4 was conducted: the reflectivity of the coated reflective film sample was tested in the range of 360nm to 740nm using the UltraScan VIS spectrophotometer from HunterLab. The reflectivity curve is shown in the results. Figure 4 As shown by Figure 4 It can be seen that there is an obvious depression at 590 nm, which is due to the absorption of yellow-orange light at this wavelength by CuTAP@ZIF-8 in the reflective film coating 20 .

[0160] Test Example 3 The reflective films prepared in Examples 4 to 10 and Comparative Examples 1 to 11 were subjected to performance tests in the following manner.

[0161] Luminance and color coordinate test: Assemble the reflective films into a backlight in the following order from bottom to top: KSF lamp → reflective film → light guide plate → diffuser → prism sheet (90°) → prism sheet (0°) → diffuser. Use a BM-7A luminance meter from TOPCON to perform luminance and color coordinate tests.

[0162] The reflectivity test is the same as that in Test Example 2.

[0163] The test results are shown in Table 1.

[0164] Table 1 Test results

[0165] As can be seen in Table 1, the color gamut enhancement effect increases with increasing concentration of the tetraazaporphyrin compound. However, the addition of a large amount of the tetraazaporphyrin compound also results in a significant loss of brightness. Therefore, it is necessary to balance the contradiction between color gamut enhancement and brightness loss during sample preparation.

[0166] Furthermore, the data in the table clearly show that under 800 hours of illumination, the reflectivity at 590 nm of the sample containing CuTAP significantly rebounded and approached that of Comparative Example 1, which did not contain CuTAP. This indicates that the CuTAP in Coating 20 decomposes under illumination. In contrast, the reflectivity of the sample containing CuTAP@ZIF-8 remained virtually unchanged before and after illumination, demonstrating that the ZIF-8 shell coating significantly enhances the photostability of CuTAP.

[0167] The reflectivity of the samples in Comparative Examples 8 and 9 at 590 nm before and after illumination showed a rebound similar to that in Comparative Examples 2 to 6, but the brightness loss was serious, indicating that excessive or slow droplet acceleration during the reaction process had an adverse effect on the growth of the shell.

[0168] In summary, the modified tetraazaporphyrin compound 22 provided by the present invention can absorb stray light in the 580nm-640nm wavelength range from backlight sources, improving its color purity. By preparing a reflective film from the modified tetraazaporphyrin compound 22, the reflective film can be made light-resistant and exhibit a wide color gamut. This reflective film can further be used in display devices.

[0169] The foregoing description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Those skilled in the art will readily appreciate that various modifications and variations of the present invention are possible. Any modifications, equivalent substitutions, or improvements made within the spirit and principles of the present invention are intended to be within the scope of protection of the present invention.

Claims

1. A reflective film, characterized in that: The reflective film includes a base film and a coating layer arranged on the surface of the base film; The coating contains a modified tetraazametalloporphyrin compound; The modified tetraazametalloporphyrin compound has a core-shell structure, wherein the core is tetraazametalloporphyrin and the shell is a zeolite imidazolate framework; The chemical formula of the tetraazametalloporphyrin is: ; wherein R1 to R8 independently include: a hydrogen atom, a halogen element, a branched or cyclic aliphatic hydrocarbon group having 3 to 10 carbon atoms, an aromatic hydrocarbon group, a hydroxyl group, a sulfonic acid group or an amino group; M is a divalent metal ion; The zeolite imidazolate framework contains Zn for coordinating with N in the tetraazametalloporphyrin. 2+ .

2. The reflective film according to claim 1, wherein M includes Cu 2+ 、Zn 2+ 、Co 2+ Mg 2+ 、Be 2+ , Pb 2+ 、Sn 2 + 、Ba 2+ or Fe 2+ .

3. The reflective film according to claim 1 or 2, wherein: The preparation method of the modified tetraazametalloporphyrin compound comprises the following steps: mixing a tetraazametalloporphyrin colloidal solution with zinc acetate to form a pre-coordination complex; dropping a 2-methylimidazole dispersion into the pre-coordination complex to carry out a coordination reaction to form the shell; and drying to obtain the modified tetraazametalloporphyrin compound.

4. The reflective film according to claim 3, wherein The preparation of the modified tetraazametalloporphyrin compound includes at least one of the following features: Feature 1: The tetraazametalloporphyrin colloidal solution and the Zn in the zinc acetate 2+ The molar ratio is 1:18 to 1:22; Feature 2: The 2-methylimidazole dispersion comprises 2-methylimidazole and N,N-dimethylformamide in a mass ratio of 0.8:100 to 1.2:100; Feature 3: The volume ratio of the 2-methylimidazole dispersion to the pre-coordinated complex is 1.8:1 to 2.2:1; Feature 4: The dropping speed of the 2-methylimidazole dispersion is 0.45 L / min to 0.55 L / min; Feature 5: The dropping temperature is 20℃~30℃, and the dropping time is 6h~24h.

5. The reflective film according to claim 3, wherein The preparation of the tetraazametalloporphyrin colloidal solution comprises: dispersing the tetraazametalloporphyrin in a solvent, and performing ultrasonic treatment under ice bath conditions to form a colloid.

6. The reflective film according to claim 5, wherein The preparation of the tetraazametalloporphyrin comprises: dissolving phthalonitrile and metal chloride in a mixed solvent and refluxing under a protective atmosphere.

7. The reflective film according to claim 6, wherein The metal chloride is a chloride of the element M in the chemical formula of the tetraazametalloporphyrin; The molar ratio of the phthalonitrile to the metal chloride is 3.5:1 to 4.5:1; The mixed solvent comprises 1,8-diazabicycloundec-7-ene and 1-pentanol in a volume ratio of 1:2.5 to 1:3.5; The reflux temperature is 155°C~165°C, and the reflux time is 4h~8h.

8. A method for preparing a reflective film according to any one of claims 1 to 7, characterized in that: The following steps are involved: The coating layer is prepared on the surface of the base film.

9. The preparation method according to claim 8, characterized in that When the coating contains a modified tetraazametalloporphyrin compound, organic coating particles, an adhesive and an auxiliary agent, the preparation of the coating includes the following steps: mixing the adhesive, the organic coating particles, the auxiliary agent and a fatty acid ester solvent to obtain a first coating liquid; adding a dispersion of the modified tetraazametalloporphyrin compound to the first coating liquid, and ultrasonicating to obtain a final coating liquid; coating the final coating liquid on the surface of the base film, and thermally curing.

10. A display device, characterized in that: The display device comprises the reflective film according to any one of claims 1 to 7.

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