OMTD photoelectric mapping transparent display film with adjustable light transmittance and preparation method of OMTD photoelectric mapping transparent display film

Abstract

The invention discloses an OMTD photoelectric mapping transparent display film with adjustable light transmittance and a preparation method, and belongs to the technical field of transparent display films. The transparent display film comprises an electric control dimming film layer, a fluorescent layer, an adhesive layer and a release material layer, wherein the fluorescent layer comprises the following raw materials in parts by weight: 80-100 parts of polyurethane resin, 2-5 parts of a fluorescent agent, 3-6 parts of a dispersing agent, 4-8 parts of a modified anti-aging agent, 1-10 parts of a curing agent and 200 parts of a solvent; according to the invention, p-phenylenediamine and 4-(diethylamino) salicylaldehyde react to prepare a fluorescent small molecule substance, and then the fluorescent small molecule substance is introduced into a polyurethane chain to finally prepare the fluorescent agent. The prepared transparent display film has excellent fluorescence performance, transparency and anti-aging performance.

Description

Technical Field

[0001] The present invention relates to the technical field of transparent display films, and in particular to an OMTD photoelectric mapping transparent display film with adjustable transmittance and a preparation method thereof. Background Art

[0002] OMTD (Opto-electronic mapping transparent display film) optoelectronic mapping transparent display film is a new type of functional optoelectronic film. Through the control of an external electric field, the optoelectronic film can be transformed between colorless and transparent and milky white opaque states. With the advancement of dimming film technology and the continuous improvement of its performance, optoelectronic mapping transparent display film has begun to be used in automobiles. In order to meet the market's demand for personalization and aesthetics, by adding fluorescent dyes of different wavelengths, the OMTD optoelectronic film can display different patterns, thus providing users with a more personalized choice. However, when the optoelectronic mapping transparent display film is applied to the car sunroof, there is a problem of insufficient transparency, which limits its performance in display clarity and visual experience; secondly, insufficient display brightness is also a problem, especially in an environment with strong natural light, the brightness of the transparent display is often difficult to compete with the background light, resulting in poor display effect. In addition, the existing technology still has certain haze problems and light aging phenomena, which affect the clarity and transparency of the display, especially in application scenarios with high transparency requirements, such as car windows and outdoor exhibitions, light aging will seriously affect the display effect. Therefore, it is particularly important to develop a photoelectric mapping transparent display film with high transparency, good fluorescence and anti-aging.

[0003] A Chinese invention patent with publication number CN108285746A discloses a transparent display film with a blue light protection function, a preparation method thereof, and a projection system with the transparent display film. The transparent display film includes a projection display layer, a substrate layer, an adhesive layer, and a release material layer stacked in sequence; the raw material formula of the projection display layer includes 70-99.4% of resin, 0.1%-5% of scattering particle material, 0.3%-9% of blue light absorber, 0.1%-6% of dispersant, and 0.1%-10% of curing agent. The transparent display film obtained by the invention contains a blue light absorber, so that the residual high-energy blue light is absorbed by the blue light absorber, but its transparency, fluorescent brightness, anti-aging and other properties are poor. Summary of the invention

[0004] In view of the deficiencies in the prior art, an object of the present invention is to provide an OMTD photoelectric mapping transparent display film with adjustable transmittance and a preparation method thereof.

[0005] To achieve the above object, the present invention is implemented through the following technical solutions: An OMTD photoelectric mapping transparent display film with adjustable transmittance, comprising an electrically controlled dimming film layer, a fluorescent layer, an adhesive layer, and a release material layer; The fluorescent layer comprises the following raw materials in parts by weight: 80-100 parts of polyurethane resin, 2-5 parts of fluorescent agent, 3-6 parts of dispersant, 4-8 parts of modified antioxidant, and 1-10 parts of curing agent; The fluorescent agent is prepared by the following method: S1: p-phenylenediamine reacts with 4-(diethylamino) salicylaldehyde under the action of glacial acetic acid as a catalyst to obtain a fluorescent small molecule substance. The reaction equation is as follows:

[0006] S2: Under nitrogen protection, 1,3-bis(2-isocyano-2-propyl)benzene and polytetrahydrofuran ether diol react under the action of dibutyltin dilaurate as a catalyst to obtain a polyurethane prepolymer. The reaction equation is as follows:

[0007] S3: The fluorescent small molecule substance, polyurethane prepolymer, and 2,2-dimethylol propionic acid are subjected to chain extension and cross-linking reaction, triethylamine is added for neutralization, and then deionized water is added for emulsification to obtain a fluorescent agent. The reaction equation is shown as follows:

[0008] in, represent:

[0009] represent:

[0010] m, p, q, s, and t are all natural numbers.

[0011] It should be noted that the above reaction equation is merely a schematic diagram and is only used to illustrate possible reaction examples between related functional groups.

[0012] The adhesive used in the adhesive layer is an acrylic adhesive.

[0013] The release material layer is a polyethylene release film.

[0014] The dispersant is one of Solsperse-32500, Solsperse-6000 and Solsperse-39000.

[0015] The modified antioxidant is prepared by copolymerizing 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol, glycidyl methacrylate and polyethylene glycol methyl ether acrylate.

[0016] The curing agent is one of Desmodur N3300, Desmodur N3390 and Desmodur N3600.

[0017] The solvent is one of xylene, methyl isobutyl ketone and tetrahydrofuran.

[0018] In the step S1, the mass ratio of p-phenylenediamine to 4-(diethylamino) salicylaldehyde is (3-5):(8-10); in the step S2, the mass ratio of 1,3-bis(2-isocyano-2-propyl)benzene to polytetrahydrofuran ether diol is (4-6):(6-10); in the step S3, the mass ratio of fluorescent small molecule substance, polyurethane prepolymer and 2,2-dihydroxymethylpropionic acid is (1-3):(10-15):(5-10).

[0019] A method for preparing an OMTD photoelectric mapping transparent display film with adjustable transmittance comprises the following steps: S1: Weigh by weight: 80-100 parts of polyurethane resin, 2-5 parts of fluorescent agent, 3-6 parts of dispersant, 4-8 parts of modified antioxidant, 1-10 parts of curing agent, and 200 parts of solvent; stir and mix evenly to obtain a fluorescent resin material; S2: Evenly apply the fluorescent resin material on one side of the electrically controlled dimming film layer using a micro-concave roller, and solidify and shape it to obtain a fluorescent layer; S3: coating an adhesive on the other side of the electrically controlled dimming film layer to obtain an adhesive layer; S4: Compounding the release material layer and the adhesive layer, and rolling them up to obtain a transparent display film.

[0020] Due to the adoption of the above technical solution, the beneficial effects of the present invention include: (1) The present invention prepares a fluorescent small molecule substance by reacting p-phenylenediamine with 4-(diethylamino) salicylaldehyde, and prepares a polyurethane prepolymer by reacting 1,3-bis(2-isocyano-2-propyl)benzene and polytetramethylene glycol. Subsequently, the fluorescent small molecule substance is introduced into the polyurethane chain by chain extension and cross-linking, and finally a fluorescent agent is prepared.

[0021] (2) The fluorescent agent of the present invention is prepared by a one-step reaction method to prepare a fluorescent small molecule substance with Schiff base, which has excellent coordination ability and photoelectric effect; the fluorescent small molecule is connected to the molecular chain of polyurethane by chemical bonding, and the fluorescent group is evenly dispersed in the polyurethane matrix, which solves the shortcomings of poor stability and poor solubility of the fluorescent small molecule substance. On the other hand, the salt-forming agent triethylamine added in the synthesis process of the polyurethane dispersion reacts with the carboxyl group on the side chain of the polyurethane to make the polyurethane chain carry a negative charge, so that the fluorescent agent molecular chain can curl into a group in different ways in the solution to form a double electron layer structure, which also plays a shielding role for the fluorescent small molecule substance embedded in the polyurethane chain, that is, the polymer chain plays a protective role for the fluorescent substance in the excited singlet state, which is conducive to the competition between the radiation deactivation process (fluorescence) and the non-radiation deactivation process and various quenching processes, thereby improving the fluorescence quantum yield and enhancing the fluorescence intensity.

[0022] (3) The modified antioxidant polymer prepared by the present invention contains epoxy groups provided by glycidyl methacrylate, which increases the compatibility between the modified antioxidant and polyurethane. 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol contains benzotriazole groups, which can be used as an ultraviolet absorber, which can not only broaden the absorption range but also increase the molar absorption coefficient; however, due to its small molecular weight, it is not resistant to migration; the modified antioxidant prepared by copolymerizing 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol, glycidyl methacrylate and polyethylene glycol methyl ether acrylate increases the molecular weight and improves the migration resistance. Therefore, adding the modified antioxidant to the photoelectric mapping transparent display film improves its anti-ultraviolet and anti-aging capabilities. DETAILED DESCRIPTION

[0023] The invention will be further described below in conjunction with the embodiments, but the invention is not limited to these embodiments.

[0024] Example 1 Preparation of fluorescent agent: S1: Add 200g of anhydrous ethanol, 30g of p-phenylenediamine, and 80g of 4-(diethylamino) salicylaldehyde into the reactor, stir to dissolve, heat to 50°C, then add 1ml of glacial acetic acid, reflux for 5h, and after the reaction is completed, let it stand and filter to obtain a brick-red solid, then wash it three times with anhydrous ethanol (using 30g of anhydrous ethanol each time), and vacuum dry it at 50°C for 5h to obtain a fluorescent small molecule substance.

[0025] S2: Under nitrogen protection, 200g DMSO and 40g 1,3-bis(2-isocyano-2-propyl)benzene were added into the reactor in sequence, stirred to dissolve, heated to 80°C, and then 60g polytetramethylene glycol (PTMG-1000) was slowly added dropwise for 20min. After the addition, 0.1g catalyst dibutyltin dilaurate was added and the reaction was carried out for 10h to obtain a polyurethane prepolymer.

[0026] S3: Add 500g DMSO, 10g fluorescent small molecule substance, 50g 2,2-dihydroxymethylpropionic acid, and 100g polyurethane prepolymer into the reactor, stir to dissolve, heat to 80°C, slowly add 0.5g dibutyltin dilaurate, react for 8h. After the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 40g triethylamine under high-speed stirring (3000r / min) to neutralize for 10min, and then add 200g deionized water for shear emulsification for 20min to obtain the fluorescent agent.

[0027] Example 2 Preparation of fluorescent agent: S1: Add 200g of anhydrous ethanol, 40g of p-phenylenediamine, and 90g of 4-(diethylamino) salicylaldehyde into the reactor, stir to dissolve, heat to 55°C, then add 1.5ml of glacial acetic acid, reflux for 4h, let stand after the reaction, filter to obtain a brick-red solid, then wash three times with anhydrous ethanol (30g of anhydrous ethanol each time), and dry under vacuum at 60°C for 4h to obtain a small molecule fluorescent substance.

[0028] S2: Under nitrogen protection, 200g DMSO and 50g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 80g polytetramethylene glycol (PTMG-1000) was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0029] S3: Add 500g DMSO, 20g fluorescent small molecule substance, 75g 2,2-dihydroxymethylpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, react for 6h, after the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0030] Example 3 Preparation of fluorescent agent: S1: Add 200g of anhydrous ethanol, 50g of p-phenylenediamine, and 100g of 4-(diethylamino) salicylaldehyde into the reactor, stir to dissolve, heat to 60°C, then add 2ml of glacial acetic acid, reflux for 3h, and after the reaction is completed, let it stand and filter to obtain a brick-red solid, then wash it three times with anhydrous ethanol (using 30g of anhydrous ethanol each time), and vacuum dry it at 70°C for 3h to obtain a small molecule fluorescent substance.

[0031] S2: Under nitrogen protection, 200g DMSO and 60g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 100°C, and then 100g polytetramethylene glycol (PTMG-1000) was slowly added dropwise for 20min. After the addition, 0.3g catalyst dibutyltin dilaurate was added and the reaction was carried out for 6h to obtain a polyurethane prepolymer.

[0032] S3: Add 500g DMSO, 30g fluorescent small molecule substance, 100g 2,2-dihydroxymethylpropionic acid, and 150g polyurethane prepolymer into the reactor, stir to dissolve, heat to 100℃, slowly add 1.0g dibutyltin dilaurate, react for 4h. After the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 60g triethylamine under high-speed stirring (3000r / min) to neutralize for 15min, and then add 250g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0033] Example 4 Preparation of modified antioxidant: Under nitrogen protection, 300g toluene and 70g 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol were added to the reactor, stirred, and heated to 80°C. At the same time, 60g glycidyl methacrylate, 1.5g AIBN and 110g polyethylene glycol methyl ether acrylate were slowly added dropwise for 20min. After the addition was completed, the reaction was carried out for 7h, cooled to room temperature, the supernatant was removed, washed with 200ml petroleum ether, and vacuum dried at 55°C for 3h to obtain a modified antioxidant with a number average molecular weight of 7520.

[0034] Example 5 Preparation of transparent display film: S1: Weigh 800 g of polyurethane resin, 20 g of fluorescent agent (prepared in Example 1), 30 g of dispersant (Solsperse-32500), 40 g of modified antioxidant (prepared in Example 4), 10 g of curing agent (Desmodur N3300), and 2000 g of xylene, stir and mix them evenly to obtain a fluorescent resin material; S2: The fluorescent resin material is evenly coated on one side of the electrically controlled dimming film by a micro-concave roller, and cured to obtain a fluorescent layer with a thickness of 50 μm; S3: using a glue coating machine to apply an acrylic adhesive on the other side of the electrically controlled dimming film to form an adhesive layer with a thickness of 30 μm; S4: Compounding the polyethylene release film with the adhesive layer and rolling them up to obtain a transparent display film.

[0035] Example 6 Preparation of transparent display film: S1: Weigh 900 g of polyurethane resin, 30 g of fluorescent agent (prepared in Example 2), 45 g of dispersant (Solsperse-6000), 60 g of modified antioxidant (prepared in Example 4), 50 g of curing agent (Desmodur N3390), and 2000 g of methyl isobutyl ketone, stir and mix them evenly to obtain a fluorescent resin material; S2: The fluorescent resin material is evenly coated on one side of the electrically controlled dimming film by a micro-concave roller, and cured to obtain a fluorescent layer with a thickness of 50 μm; S3: using a glue coating machine to apply an acrylic adhesive on the other side of the electrically controlled dimming film to form an adhesive layer with a thickness of 30 μm; S4: Compounding the polyethylene release film with the adhesive layer and rolling them up to obtain a transparent display film.

[0036] Example 7 Preparation of transparent display film: S1: Weigh 1000 g of polyurethane resin, 50 g of fluorescent agent (prepared in Example 3), 60 g of dispersant (Solsperse-39000), 80 g of modified antioxidant (prepared in Example 4), 100 g of curing agent (Desmodur N3600), and 2000 g of tetrahydrofuran, stir and mix them evenly, and prepare a fluorescent resin material; S2: The fluorescent resin material is evenly coated on one side of the electrically controlled dimming film by a micro-concave roller, and cured to obtain a fluorescent layer with a thickness of 50 μm; S3: using a glue coating machine to apply an acrylic adhesive on the other side of the electrically controlled dimming film to form an adhesive layer with a thickness of 30 μm; S4: Compounding the polyethylene release film with the adhesive layer and rolling them up to obtain a transparent display film.

[0037] Comparative Example 1 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced by an equal weight of 7-amino-4-trifluoromethylcoumarin.

[0038] Comparative Example 2 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced by an equal weight of fluorescein isothiocyanate.

[0039] Comparative Example 3 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced with an equal weight of a fluorescent agent prepared by the following method: S1: Add 200g of anhydrous ethanol, 40g of acridinium yellow hydrochloride, and 90g of 4-(diethylamino) salicylaldehyde into the reactor, stir to dissolve, heat to 55°C, then add 1.5ml of glacial acetic acid, reflux for 4h, let stand after the reaction, filter to obtain a brick-red solid, then wash three times with anhydrous ethanol (30g of anhydrous ethanol each time), and dry under vacuum at 60°C for 4h to obtain a small molecule fluorescent substance.

[0040] S2: Under nitrogen protection, 200g DMSO and 50g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 80g polytetramethylene glycol (PTMG-1000) was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0041] S3: Add 500g DMSO, 20g fluorescent small molecule substance, 75g 2,2-dihydroxymethylpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, react for 6h, after the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0042] Comparative Example 4 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced with an equal weight of a fluorescent agent prepared by the following method: S1: Add 200g of anhydrous ethanol, 40g of p-phenylenediamine, and 90g of 4-hydroxybenzaldehyde into the reactor, stir to dissolve, heat to 55°C, then add 1.5ml of glacial acetic acid, reflux for 4h, let stand after the reaction, filter to obtain a brick-red solid, then wash three times with anhydrous ethanol (30g of anhydrous ethanol each time), and vacuum dry at 60°C for 4h to obtain a small molecule fluorescent substance.

[0043] S2: Under nitrogen protection, 200g DMSO and 50g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 80g polytetramethylene glycol (PTMG-1000) was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0044] S3: Add 500g DMSO, 20g fluorescent small molecule substance, 75g 2,2-dihydroxymethylpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, react for 6h, after the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0045] Comparative Example 5 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced with an equal weight of a fluorescent agent prepared by the following method: S1: Add 200g of anhydrous ethanol, 40g of p-phenylenediamine, and 90g of 4-(diethylamino) salicylaldehyde into the reactor, stir to dissolve, heat to 55°C, then add 1.5ml of glacial acetic acid, reflux for 4h, let stand after the reaction, filter to obtain a brick-red solid, then wash three times with anhydrous ethanol (30g of anhydrous ethanol each time), and dry under vacuum at 60°C for 4h to obtain a small molecule fluorescent substance.

[0046] S2: Under nitrogen protection, 200g DMSO and 50g isophorone diisocyanate were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 80g polytetramethylene glycol (PTMG-1000) was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0047] S3: Add 500g DMSO, 20g fluorescent small molecule substance, 75g 2,2-dihydroxymethylpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, react for 6h, after the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0048] Comparative Example 6 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced with an equal weight of a fluorescent agent prepared by the following method: S1: Add 200g of anhydrous ethanol, 40g of p-phenylenediamine, and 90g of 4-(diethylamino) salicylaldehyde into the reactor, stir to dissolve, heat to 55°C, then add 1.5ml of glacial acetic acid, reflux for 4h, let stand after the reaction, filter to obtain a brick-red solid, then wash three times with anhydrous ethanol (30g of anhydrous ethanol each time), and dry under vacuum at 60°C for 4h to obtain a small molecule fluorescent substance.

[0049] S2: Under nitrogen protection, 200g DMSO and 50g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 80g polyethylene glycol (PEG-1000) was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0050] S3: Add 500g DMSO, 20g fluorescent small molecule substance, 75g 2,2-dihydroxymethylpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, react for 6h, after the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0051] Comparative Example 7 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced with an equal weight of a fluorescent agent prepared by the following method: S1: Dissolve 10.5g of ethanolamine and 10ml of salicylaldehyde in 50ml of methanol, reflux at 60℃ for 4 hours, and cool to room temperature after the reaction to obtain ethanolamine salicylaldehyde. Dissolve 11g of zinc acetate in 25mL of methanol and add dropwise to 14ml of ethanolamine salicylaldehyde solution dissolved in 50mL of methanol, heat and stir to reflux for 4h and then cool to room temperature. Remove methanol by rotary evaporation, dissolve the resulting yellow residue in 10mL of methanol and keep at room temperature for two days. After two days, collect the yellow crystals grown in the solution and recrystallize the appropriate crystals using methanol to obtain the fluorescent substance.

[0052] S2: Under nitrogen protection, 200g DMSO and 50g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 75g polytetrahydrofuran ether diol was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0053] S3: Add 500g DMSO, 20g fluorescent substance, 75g 2,2-dimethylolpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, react for 6h, after the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0054] Comparative Example 8 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the fluorescent agent in step S1 is replaced with an equal weight of a fluorescent agent prepared by the following method: S1: Under nitrogen protection, 200g DMSO and 50g 1,3-bis(2-isocyano-2-propyl)benzene were added to the reactor in sequence, stirred to dissolve, heated to 90°C, and then 75g polytetrahydrofuran ether diol was slowly added dropwise for 20min. After the addition, 0.2g catalyst dibutyltin dilaurate was added and the reaction was carried out for 8h to obtain a polyurethane prepolymer.

[0055] S2: Add 500g DMSO, 20g acridinium hydrochloride, 75g 2,2-dimethylolpropionic acid, and 120g polyurethane prepolymer into the reactor, stir to dissolve, heat to 90°C, slowly add 0.8g dibutyltin dilaurate, and react for 6h. After the reaction, add 100g acetone to adjust the viscosity, pour into an emulsification barrel, slowly add 50g triethylamine under high-speed stirring (3000r / min) to neutralize for 12min, and then add 230g deionized water to shear emulsify for 20min to obtain the fluorescent agent.

[0056] Comparative Example 9 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that no modified antioxidant is added to the fluorescent layer.

[0057] Comparative Example 10 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the modified antioxidant in step S1 is replaced by an equal weight of 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)-5-chlorobenzotriazole.

[0058] Comparative Example 11 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the modified antioxidant in step S1 is replaced by an equal weight of 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol.

[0059] Comparative Example 12 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the modified antioxidant in step S1 is replaced by an antioxidant prepared by the following method with an equal weight: Under nitrogen protection, 300g toluene and 70g 4-propyleneoxy-2-hydroxybenzophenone were added to the reactor, stirred, and heated to 80°C. At the same time, 60g glycidyl methacrylate, 1.5g AIBN and 110g polyethylene glycol methyl ether acrylate were slowly added dropwise for 20min. After the addition was completed, the reaction was carried out for 7h, cooled to room temperature, the supernatant was removed, washed with 200ml petroleum ether, and vacuum dried at 55°C for 3h to obtain a modified antioxidant.

[0060] Comparative Example 13 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the modified antioxidant in step S1 is replaced by an antioxidant prepared by the following method with an equal weight: Under nitrogen protection, add 300g toluene and 70g 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol into the reactor, stir, heat to 80°C, and slowly add 1.5g AIBN and 110g polyethylene glycol methyl ether acrylate at the same time, add for 20min, react for 7h after the addition is completed, cool to room temperature, remove the supernatant, wash with 200ml petroleum ether, and dry in vacuo at 55°C for 3h to obtain a modified antioxidant.

[0061] Comparative Example 14 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the modified antioxidant in step S1 is replaced by an antioxidant prepared by the following method with an equal weight: Under nitrogen protection, 300g toluene and 40g 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol were added to the reactor, stirred, and heated to 80°C. At the same time, 50g glycidyl methacrylate, 1g AIBN and 80g polyethylene glycol methyl ether acrylate were slowly added dropwise for 20min. After the addition was completed, the reaction was allowed to proceed for 5h, cooled to room temperature, the supernatant was removed, washed with 200ml petroleum ether, and dried under vacuum at 55°C for 3h to obtain a modified antioxidant with a number average molecular weight of 4370.

[0062] Comparative Example 15 An OMTD photoelectric mapping transparent display film with adjustable transmittance, the raw material composition and process are basically the same as those of Example 6, the difference being that the modified antioxidant in step S1 is replaced by an antioxidant prepared by the following method with an equal weight: Under nitrogen protection, 300g toluene and 100g 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol were added to the reactor, stirred, and heated to 80°C. At the same time, 80g glycidyl methacrylate, 2g AIBN and 150g polyethylene glycol methyl ether acrylate were slowly added dropwise for 20min. After the addition was completed, the reaction was carried out for 10h, cooled to room temperature, the supernatant was removed, washed with 200ml petroleum ether, and vacuum dried at 55°C for 3h to obtain a modified antioxidant with a number average molecular weight of 12650.

[0063] Comparative Example 16 A transparent display film with blue light protection function is prepared by using the raw material composition, proportion and method of Example 1 of the Chinese invention patent with publication number CN108285746A.

[0064] The electrically controlled dimming film layer used in the embodiments and comparative examples of the present application has a thickness of 0.5 mm and is purchased from Beijing Wendys New Material Technology Co., Ltd.; the acrylate adhesive model is DP810NS, purchased from Shenzhen Fusheng Loctite Glue Co., Ltd.; the polyethylene release film model is LPFM-G100, with a thickness of 0.15 mm, purchased from Nantong Lipeng New Materials Co., Ltd.; the polyurethane resin model is Leasys® 3979 (solid content 40wt%) produced by Wanhua Chemical; the number average molecular weight of polyethylene glycol methyl ether acrylate is 480.

[0065] The transparent display film prepared in the present application adjusts the transmittance through an electrically controlled dimming film. The electrically controlled dimming film is an intelligent light-control material. Its principle is to use electromagnetic action and conduction effect to adjust the luminous flux and achieve controllable light transmittance. This technology is an existing technology. The fluorescent brightness is adjusted through the fluorescent layer, so that the glass with the transparent display film can display personalized patterns, and the display effect can achieve high-definition and high-realism. The OMTD photoelectric mapping transparent display film can add a touch of romance to the interior environment of the car through unique light and shadow effects, and enhance the user's driving experience. For example, when driving at night, the OMTD photoelectric mapping transparent display film combined with the intelligent lighting system in the car can create a starry sky-like visual effect, giving the driver and passengers an immersive feeling and enhancing the fun of the driving process.

[0066] The photoelectric mapping transparent display films prepared in Examples 5-7 and Comparative Examples 1-16 of the present application and the aged photoelectric mapping transparent display films were tested for light transmittance according to the method of GB / T 2410-2008 "Determination of light transmittance and haze of transparent plastics".

[0067] The photoelectric mapping transparent display films prepared in Examples 5 to 7 and Comparative Examples 1 to 16 of the present application and the aged photoelectric mapping transparent display films were tested for fluorescence brightness by a fluorescence brightness meter.

[0068] The photoelectric mapping transparent display films prepared in Examples 5-7 and Comparative Examples 1-16 of the present application were subjected to UV aging tests, and the test method was carried out according to the method of GB / T 16422.3-2014 "Plastic Laboratory Light Source Exposure Test Method". The test results are shown in Table 1.

[0069] Table 1

[0070] It can be seen from Table 1 that the transparency of the photoelectric mapping transparent display film prepared by the present invention is greater than 96%, and the fluorescence brightness is greater than 170 cd / m 2 , the transmittance and fluorescence intensity are also high after aging, and it has excellent transparency, fluorescence brightness and anti-aging properties.

[0071] The raw material composition and process of Comparative Example 1 are basically the same as those of Example 6, except that the fluorescent agent is replaced by an equal weight of 7-amino-4-trifluoromethyl coumarin. It can be seen from the data in Table 1 that its transparency is 96.6% and the fluorescence brightness is 150.6 cd / m 2 After aging, the transmittance is 92.5% and the fluorescence brightness is 132.2cd / m 2 , the transparency is better after aging, but the fluorescence brightness is poor.

[0072] The raw material composition and process of Comparative Example 2 are basically the same as those of Example 6, except that the fluorescent agent is replaced by fluorescein isothiocyanate. From the data in Table 1, it can be seen that the transparency is 97.2% and the fluorescence brightness is 155.2 cd / m 2 After aging, the transmittance is 92.8% and the fluorescence brightness is 136.7cd / m 2 Although its transparency and anti-aging performance are good, its fluorescent brightness is average.

[0073] The raw material composition and process of Comparative Example 3 are basically the same as those of Example 6, except that p-phenylenediamine in step S1 of the fluorescent agent preparation process is replaced by acridinium yellow hydrochloride. It can be seen from the data in Table 1 that its transparency is 96.9% and its fluorescent brightness is 160.9 cd / m 2 After aging, the transmittance is 93.1% and the fluorescence brightness is 144.5cd / m 2 , its fluorescence brightness and transmittance after aging are not as good as those of the present application.

[0074] The raw material composition and process of Comparative Example 4 are basically the same as those of Example 6, except that 4-(diethylamino) salicylaldehyde in step S1 of the fluorescent agent preparation process is replaced by 4-hydroxybenzaldehyde. It can be seen from the data in Table 1 that its transparency is 96.1% and the fluorescent brightness is 165.7 cd / m 2 After aging, the transmittance is 89.2% and the fluorescence brightness is 145.4cd / m 2 , its transparency is better after aging, but its fluorescence brightness is average.

[0075] The raw material composition and process of Comparative Example 5 are basically the same as those of Example 6, except that 1,3-bis(2-isocyano-2-propyl)benzene in step S2 of the fluorescent agent preparation process is replaced by an equal weight of isophorone diisocyanate. It can be seen from the data in Table 1 that its transparency is 97.3% and the fluorescent brightness is 168.4 cd / m 2 After aging, the transmittance is 87.6% and the fluorescence brightness is 150.0cd / m 2 Although its transparency is good, its fluorescence brightness is average.

[0076] The raw material composition and process of Comparative Example 6 are basically the same as those of Example 6, except that the polytetrahydrofuran ether glycol in step S2 of the fluorescent agent preparation process is replaced by polyethylene glycol of equal weight. It can be seen from the data in Table 1 that its transparency is 97.8% and the fluorescent brightness is 170.0 cd / m 2 After aging, the transmittance is 85.3% and the fluorescence brightness is 152.7cd / m 2 , its transparency and fluorescent brightness after aging are not as good as those of the transparent display film prepared in Example 6 of the present application.

[0077] The raw material composition and process of Comparative Example 7 are basically the same as those of Example 6, except that different fluorescent small substances are added. It can be seen from the data in Table 1 that its transparency is 97.3% and its fluorescent brightness is 162.4 cd / m 2 After aging, the transmittance is 92.1% and the fluorescence brightness is 143.4cd / m 2 Although its transparency is good, its fluorescence brightness is poor.

[0078] The raw material composition and process of Comparative Example 8 are basically the same as those of Example 6, except that the preparation method of the fluorescent agent is different. It can be seen from the data in Table 1 that its transparency is 98.0% and the fluorescent brightness is 166.8 cd / m 2 After aging, the transmittance is 92.9% and the fluorescence brightness is 148.2cd / m 2 , indicating that the fluorescence brightness of the transparent display film prepared by this method is average.

[0079] The raw material composition and process of Comparative Example 9 are basically the same as those of Example 6, except that no modified antioxidant is added to the fluorescent layer. From the data in Table 1, it can be seen that the transparency is 97.4% and the fluorescent brightness is 169.9 cd / m 2 After aging, the transmittance is 75.3% and the fluorescence brightness is 141.7cd / m 2 , indicating that the transparent display film prepared without adding modified antioxidant in the fluorescent layer has a significant decrease in fluorescence brightness and transparency after aging test.

[0080] The raw material composition and process of Comparative Example 10 are basically the same as those of Example 6, except that the modified antioxidant added to the fluorescent layer is replaced by an equal weight of 2-(2′-hydroxy-3′,5′-di-tert-butylphenyl)-5-chlorobenzotriazole. It can be seen from the data in Table 1 that its transparency is 97.3% and the fluorescent brightness is 170.4 cd / m 2 After aging, the transmittance is 82.1% and the fluorescence brightness is 146.4cd / m 2 , small molecule antioxidants that simply have anti-aging functional groups have poor anti-aging performance.

[0081] The raw material composition and process of Comparative Example 11 are basically the same as those of Example 6, except that the modified antioxidant added to the fluorescent layer is replaced by an equal weight of 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol. It can be seen from the data in Table 1 that its transparency is 98.6% and the fluorescent brightness is 172.0 cd / m 2 After aging, the transmittance is 84.7% and the fluorescence brightness is 149.2cd / m 2 , the fluorescence brightness is better before aging, but worse after aging.

[0082] The raw material composition and process of Comparative Example 12 are basically the same as those of Example 6, except that the substrate 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol in the preparation process of the modified anti-aging agent in the fluorescent layer is replaced by 4-propyleneoxy-2-hydroxybenzophenone. It can be seen from the data in Table 1 that its transparency is 96.5% and the fluorescence brightness is 166.8 cd / m 2 After aging, the transmittance is 87.0% and the fluorescence brightness is 150.7cd / m 2 , the fluorescence brightness is poor after aging.

[0083] The raw material composition and process of Comparative Example 13 are basically the same as those of Example 6, except that glycidyl methacrylate is not added during the preparation of the modified antioxidant. It can be seen from the data in Table 1 that its transparency is 97.7% and its fluorescence brightness is 169.5 cd / m 2 After aging, the transmittance is 85.6% and the fluorescence brightness is 151.2cd / m 2 , indicating that when glycidyl methacrylate is not added during the preparation of the modified antioxidant, the anti-aging performance is general.

[0084] The raw material composition and process of Comparative Example 14 are basically the same as those of Example 6, except that the number average molecular weight of the modified antioxidant is 4370. It can be seen from the data in Table 1 that its transparency is 96.8% and its fluorescent brightness is 169.1 cd / m 2 After aging, the transmittance is 90.1% and the fluorescence brightness is 156.7cd / m 2 The number average molecular weight of the modified antioxidant has a certain influence on the anti-aging performance.

[0085] The raw material composition and process of Comparative Example 15 are basically the same as those of Example 6, except that the number average molecular weight of the modified antioxidant is 12650. It can be seen from the data in Table 1 that its transparency is 97.6% and its fluorescent brightness is 167.5 cd / m 2 After aging, the transmittance is 89.7% and the fluorescence brightness is 155.4cd / m 2 , the transparency is better, but the anti-aging performance is not as good as Example 6.

[0086] Comparative Example 16 is a transparent display film with blue light protection function prepared by using the raw material composition, ratio and method of Example 1 of the Chinese invention patent publication number CN108285746A. It can be seen from the data in Table 1 that its transparency is 93.1% and the fluorescent brightness is 155.7 cd / m 2 After aging, the transmittance is 87.0% and the fluorescence brightness is 143.7cd / m 2The transparency, fluorescent brightness and anti-aging performance are not as good as those of the transparent display film prepared in Example 6.

[0087] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. However, any equivalent changes, modifications and evolutions made by ordinary technicians in the field without departing from the scope of the technical solution of the present invention by using the technical content disclosed above are all equivalent embodiments of the present invention. At the same time, any equivalent changes, modifications and evolutions made to the above embodiments based on the essential technology of the present invention are still within the protection scope of the technical solution of the present invention.

Claims

1. An OMTD photoelectric mapping transparent display film with adjustable transmittance, characterized in that: It includes an electrically controlled dimming film layer, a fluorescent layer, an adhesive layer, and a release material layer; The fluorescent layer comprises the following raw materials in parts by weight: 80-100 parts of polyurethane resin, 2-5 parts of fluorescent agent, 3-6 parts of dispersant, 4-8 parts of modified antioxidant, 1-10 parts of curing agent, and 200 parts of solvent; The fluorescent agent is prepared by the following method: S1: p-phenylenediamine reacts with 4-(diethylamino) salicylaldehyde in the presence of glacial acetic acid to obtain a fluorescent small molecule substance; S2: Under nitrogen protection, 1,3-bis(2-isocyano-2-propyl)benzene and polytetrahydrofuran ether diol react under the action of a catalyst, dibutyltin dilaurate, to obtain a polyurethane prepolymer; S3: A fluorescent small molecule substance, a polyurethane prepolymer, and 2,2-dimethylol propionic acid are subjected to a chain extension and cross-linking reaction, triethylamine is added for neutralization, and then deionized water is added for emulsification to obtain a fluorescent agent.

2. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: The adhesive used in the adhesive layer is an acrylic adhesive.

3. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: The release material layer is a polyethylene release film.

4. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: The dispersant is one of Solsperse-32500, Solsperse-6000 and Solsperse-39000.

5. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: The modified antioxidant is prepared by copolymerizing 2-(2H-benzotriazole-2-yl)-4-methyl-6-(2-methyl-2-propylene-1-yl)-phenol, glycidyl methacrylate and polyethylene glycol methyl ether acrylate.

6. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: The curing agent is one of Desmodur N3300, Desmodur N3390 and Desmodur N3600.

7. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: The solvent is one of xylene, methyl isobutyl ketone and tetrahydrofuran.

8. The OMTD photoelectric mapping transparent display film with adjustable transmittance according to claim 1, characterized in that: In the step S1, the mass ratio of p-phenylenediamine to 4-(diethylamino) salicylaldehyde is (3-5):(8-10); in the step S2, the mass ratio of 1,3-bis(2-isocyano-2-propyl)benzene to polytetrahydrofuran ether diol is (4-6):(6-10); in the step S3, the mass ratio of fluorescent small molecule substance, polyurethane prepolymer and 2,2-dihydroxymethylpropionic acid is (1-3):(10-15):(5-10).

9. A method for preparing an OMTD photoelectric mapping transparent display film with adjustable transmittance according to any one of claims 1 to 8, characterized in that: The following steps are involved: S1: Weigh by weight: 80-100 parts of polyurethane resin, 2-5 parts of fluorescent agent, 3-6 parts of dispersant, 4-8 parts of modified antioxidant, 1-10 parts of curing agent, and 200 parts of solvent; stir and mix evenly to obtain a fluorescent resin material; S2: The fluorescent resin material is evenly coated on one side of the electrically controlled dimming film layer by a micro-concave roller, and cured to obtain a fluorescent layer; S3: coating an adhesive on the other side of the electrically controlled dimming film layer to obtain an adhesive layer; S4: Compounding the release material layer and the adhesive layer, and rolling them up to obtain a transparent display film.

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