阅读说明：本技术 量子点膜的制备方法及量子点膜和背光模组 (Preparation method of quantum dot film, quantum dot film and backlight module ) 是由 马卜 徐晓波 林怡 王允军 于 2019-09-26 设计创作，主要内容包括：本申请公开了一种量子点膜的制备方法,该方法包括：步骤一、提供量子点和高分子材料；步骤二、使所述高分子材料处于熔融状态后,向至少部分所述高分子材料中混入量子点；步骤三、挤压所述高分子材料,形成量子点基膜；步骤四、对所述量子点基膜进行电晕处理；步骤五、制得量子点膜。本申请在量子点膜的中间制作过程中对量子点基膜进行电晕处理,使得量子点基膜中的量子点与高分子材料重新排列组合,从而提高了量子点膜的发光亮度。(The application discloses a preparation method of a quantum dot film, which comprises the following steps: providing quantum dots and a high polymer material; step two, mixing quantum dots into at least part of the high polymer material after the high polymer material is in a molten state; extruding the high polymer material to form a quantum dot base film; step four, carrying out corona treatment on the quantum dot base film; and step five, preparing the quantum dot film. The application carries out corona treatment to quantum dot base film in the middle manufacture process of quantum dot film for quantum dot in the quantum dot base film and macromolecular material rearrangement combination have improved the luminous luminance of quantum dot film.)

1. A method of making a quantum dot film, comprising:

providing quantum dots and a high polymer material;

step two, mixing quantum dots into at least part of the high polymer material after the high polymer material is in a molten state;

extruding the high polymer material to form a quantum dot base film;

step four, carrying out corona treatment on the quantum dot base film;

and step five, preparing the quantum dot film.

2. The method for preparing quantum dot film according to claim 1, wherein the corona treatment time in the fourth step is 1-60 s.

3. The method for preparing quantum dot film according to claim 1, wherein the voltage of corona treatment in the fourth step is 5000V-15000V.

4. The method for preparing quantum dot film according to claim 1, wherein the thickness of the quantum dot-based film in the third step is 10 μm to 300 μm.

5. The method for preparing a quantum dot film according to claim 1, wherein the step three comprises extruding the polymer material in a multilayer coextrusion casting manner, the polymer material comprises a polymer material containing quantum dots and a polymer material without quantum dots, and the polymer material containing quantum dots and the polymer material without quantum dots are coextruded to form the quantum dot-based film.

6. The method for preparing a quantum dot film according to claim 1, wherein the polymer material is extruded in the third step by a single layer extrusion casting method, and the polymer material containing quantum dots is extruded to form the quantum dot-based film.

7. The method for preparing a quantum dot film according to claim 1, wherein the second step further comprises mixing light diffusing particles and/or a hydrocarbon additive into the polymer material, and the hydrocarbon additive has a boiling point higher than a melting point of the polymer material.

8. The method of manufacturing a quantum dot film according to claim 1, further comprising:

and step six, arranging a water-oxygen barrier layer on the quantum dot film.

9. A quantum dot film, wherein the quantum dot film is prepared by the preparation method of claim 1 to 8.

10. A backlight module comprising a quantum dot film, wherein the quantum dot film is the quantum dot film of claim 9.

Technical Field

The application relates to the field of fluorescent nano materials, in particular to a preparation method of a quantum dot film.

Background

The quantum dots have excellent optical properties, such as easy adjustment of emission peak, narrow half-peak width and the like, and can be applied to the fields of display, illumination and the like. When the quantum dot material is used for display, the color gamut and other aspects are obviously improved.

The quantum dots are generally dispersed in a polymer material and then prepared into a quantum dot film for use. In the prior art, the luminous brightness of the quantum dot film is not ideal.

In order to improve the luminance of the quantum dot film, at present, the following methods are generally adopted: 1) the quantum yield of the quantum dots is improved; 2) the light transmittance of the high polymer material (glue) is improved; 3) improving the light transmittance of the water-oxygen barrier layer in the quantum dot film; 4) the method of adding light diffusion particles and the like is realized, but the method greatly increases the manufacturing cost of the quantum dot film.

Therefore, there is an urgent need for a method for improving the luminance of quantum dot films without increasing the production cost of quantum dot films.

Disclosure of Invention

The application aims to provide a preparation method of a quantum dot film, which can improve the brightness of the quantum dot film.

One aspect of the present application provides a method of preparing a quantum dot film, the method including:

providing quantum dots and a high polymer material;

step two, mixing quantum dots into at least part of the high polymer material after the high polymer material is in a molten state;

extruding the high polymer material to form a quantum dot base film;

step four, carrying out corona treatment on the quantum dot base film;

and step five, preparing the quantum dot film.

Optionally, the time of the corona treatment in the fourth step is 1s to 60 s.

Optionally, the voltage of the corona treatment in the fourth step is 5000V-15000V.

Optionally, the thickness of the quantum dot matrix film in the third step is 10 μm to 300 μm.

Optionally, the mode of extruding the polymer material in the third step is a multilayer co-extrusion casting mode, the polymer material includes a polymer material containing quantum dots and a polymer material without quantum dots, and the polymer material containing quantum dots and the polymer material without quantum dots are co-extruded to form the quantum dot base film.

Optionally, the mode of extruding the polymer material in the third step is a single-layer extrusion casting mode, and the polymer material containing quantum dots is extruded to form the quantum dot base film.

Optionally, the second step further includes mixing light diffusion particles and/or a hydrocarbon additive into the polymer material, where a boiling point of the hydrocarbon additive is higher than a melting point of the polymer material.

Optionally, the preparation method further comprises:

and step six, arranging a water-oxygen barrier layer on the quantum dot film.

The application also provides a quantum dot film, and the quantum dot film is prepared by the preparation method of the quantum dot film.

This application another aspect still provides a backlight unit, and backlight unit includes the quantum dot membrane, and the quantum dot membrane is foretell quantum dot membrane.

The application has the following beneficial effects:

this application carries out corona treatment to quantum dot base film in the middle manufacture process of quantum dot membrane for macromolecular material's hydrocarbon chain and/or carbon-carbon chain fracture recombination in the quantum dot base film, quantum dot and macromolecular material rearrangement combination, thereby improved the luminous luminance of quantum dot base film. In addition, the quantum dot base film is subjected to corona treatment, and water vapor, oil stain, dust and the like on the surface of the quantum dot base film are removed, so that the luminous brightness of the quantum dot film can be improved. Moreover, the surface roughness of the quantum dot base film can be improved by carrying out corona treatment on the quantum dot base film, so that a water and oxygen blocking layer can be conveniently arranged on the quantum dot base film subsequently.

Drawings

Fig. 1 is a flow chart of a method for fabricating a quantum dot film according to an embodiment of the present disclosure;

FIG. 2 is a flow chart of a method of fabricating a quantum dot film according to another embodiment of the present application;

FIG. 3 is a schematic structural diagram of a quantum dot film according to an embodiment of the present disclosure;

FIG. 4 is a schematic structural diagram of another embodiment of a quantum dot film according to the present application;

fig. 5 is a schematic view of a backlight module according to an embodiment of the present application.

Detailed Description

The technical solutions in the examples of the present application will be described in detail below with reference to the embodiments of the present application. It should be noted that the described embodiments are only some embodiments of the present application, and not all embodiments.

Unless otherwise defined, all terms (including technical and scientific terms) in the specification may be defined as commonly understood by one of ordinary skill in the art. Terms defined in commonly used dictionaries should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and the present disclosure, and may not be interpreted in an idealized or overly formal sense unless expressly so defined. Furthermore, unless expressly stated to the contrary, the terms "comprises" and "comprising," when used in this specification, specify the presence of stated features, regions, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, regions, integers, steps, operations, elements, components, and/or groups thereof. Thus, the above wording will be understood to mean that the stated elements are included, but not to exclude any other elements.

As used herein, the term "and/or" includes any and all combinations of one or more of the associated listed items. The term "or" means "and/or". The expression "at least one of" when preceding or following a list of elements modifies the entire list of elements without modifying individual elements of the list.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise.

As shown in fig. 1, which is a flowchart of a method for manufacturing a quantum dot film according to an embodiment of the present application, the method for manufacturing a quantum dot film includes:

step S101, providing quantum dots and a high polymer material;

in the present application, quantum dots refer to nanoparticles having three-dimensional sizes within 1nm to 100 nm. The shape of the nanoparticles includes, but is not limited to, spherical, ellipsoidal, polyhedral, and the like.

In the application, the size of the quantum dots is preferably 1-15 nm. The quantum dots may be group IIB-VIA quantum dots, group IIIA-VA quantum dots, group IVA-VIA quantum dots, group IVA quantum dots, group IB-IIIA-VIA quantum dots, group VIII-VIA quantum dots, or perovskite quantum dots, but are not limited thereto.

In the application, the IIB-VIA quantum dots are not limited to a binary element structure composed of IIB elements and VIA elements, but may be a ternary element structure, such as two IIB elements and one VIA element or one IIB element and two VIA elements; or a four-element structure, such as two IIB elements and two VIA elements. The IIB-VIA group quantum dots can be of a single-shell or multi-shell structure, for example, when the single-shell is ZnS, the IIB-VIA group quantum dots can be CdSe/ZnS, CdSeS/ZnS and the like; for example, when the multi-shell layer is ZnSe/ZnS, the IIB-VIA group quantum dots can be CdSe/ZnSe/ZnS, CdSeS/ZnSe/ZnS and the like. Similar to the IIB-VIA group quantum dots, the IIIA-VA group quantum dots, the IVA-VIA group quantum dots, the IVA group quantum dots, the IB-IIIA-VIA group quantum dots and the VIII-VIA group quantum dots are not limited to be composed of one element or two or three elements.

In an exemplary embodiment, the quantum dots include, but are not limited to, CdSe, CdTe, ZnS, ZnSe, ZnTe, ZnO, HgS, PbS, HgSe, HgTe, MgSe, MgS, PbS, CdSeS, CdSeTe, CdSTe, ZnSeS, ZnSeTe, ZnSTe, HgSeS, HgSeTe, HgSTe, CdZnS, CdZnSe, CdZnTe, CdHgS, CdHgSe、CdHgTe、HgZnS、HgZnSe、HgZnTe、MgZnSe、MgZnS、HgZnTeS、CdZnSeS、CdZnSeTe、CdZnSTe、CdHgSeS、CdHgSeTe、CdHgSTe、HgZnSeS、HgZnSeTe、HgZnSTe、GaN、GaP、GaAs、GaSb、AlN、AlP、AlAs、AlSb、InN、InP、InAs、InSb、GaNP、GaNAs、GaNSb、GaPAs、GaPSb、AlNP、AlNAs、AlNSb、AlPAs、AlPSb、InNP、InNAs、InNSb、InPAs、InPSb、GaAlNP、GaAlNAs、GaAlNSb、GaAlPAs、GaAlPSb、GaInNP、GaInNAs、GaInNSb、GaInPAs、GaInPSb、InAlNP、InAlNAs、InAlNSb、InAlPAs、InAlPSb、CuInS₂C, Si, and SiC, but are not limited thereto.

In the present application, the quantum dots may be commercially available or may be synthesized by any method. For example, quantum dots of several nanometers in size can be synthesized by wet chemical processes. In wet chemical processes, the precursors react in an organic solvent to grow the nanocrystal particles, and the organic solvent or ligand compound can coordinate (or bind) to the surface of the nanocrystals, thereby controlling the growth of the nanocrystals.

The light emission wavelength of the quantum dot is not particularly limited and may be appropriately selected. The photoluminescence wavelength of the quantum dots may be present in a range from the ultraviolet region to the near infrared region. For example, the maximum peak wavelength of the quantum dot may exist in a range from about 420 to about 750nm, but it is not limited thereto.

The quantum dots may have a Full Width Half Maximum (FWHM) of less than or equal to about 45nm, such as less than or equal to about 40nm, or less than or equal to about 30 nm. While not wanting to be bound by theory, it is understood that within such a range, a device including quantum dots may have enhanced color purity or improved color reproducibility.

In the present application, the high molecular material may include at least one of an ethylene-based polymer, a propylene-based polymer, a thiolene-based polymer, an acrylate polymer, a urethane polymer, a carbonate polymer, an epoxy polymer, and a silicone polymer, but is not limited thereto. Specifically, the polymer material may be polyethylene, polyvinylidene fluoride, polyvinyl butyral, polyvinyl alcohol, polystyrene, polypropylene, polymethyl acrylate, polymethyl methacrylate (organic glass), polydecylformamide, polyhexamethylene sebacamide, polyethylene terephthalate glycol-modified polyethylene terephthalate, polyethylene naphthalate, polycarbonate, cellulose acetate butyrate, carnauba wax, polymethylphenylsilicone, polydimethylsiloxane, or the like.

Step S102, mixing quantum dots into at least part of the high polymer material after the high polymer material is in a molten state;

in this step, the quantum dots may be mixed into at least a part of the polymer material, or may be mixed into the entire polymer material, or may be mixed into a part of the polymer material.

In this application, the polymer material may be a mixture of a plurality of polymers, and to make the polymer material in a molten state, all the polymers in the polymer material are in a molten state.

In an embodiment of the application, in order to increase the mixing uniformity of the quantum dots and the polymer material, the quantum dot high-molecular composite material with better dispersion performance is prepared. In this step, the quantum dot and/or the polymer material further contains a solvent, and the solvent is removed under normal pressure or reduced pressure in a molten state of the polymer material. For example, the solvent is selected from C₆-C₂₂Amine compound, nitrogen-containing heterocyclic compound, and C₆-C₄₀Aliphatic hydrocarbons, C₆-C₃₀Aromatic hydrocarbons, C₆-C₂₂Phosphine oxide compound and C₁₂-C₂₂At least one aromatic ether. Specifically, C₆-C₂₂Primary alkylamines, e.g. hexadecylamine, C₆-C₂₂Secondary alkylamines, e.g. dioctylamine, C₆-C₄₀Tertiary alkyl amines, e.g. trioctylamine, nitrogen-containing heterocycles, e.g. pyridine, C₆-C₄₀Alkenes, e.g. octadecene, C₆-C₄₀Aliphatic hydrocarbons, e.g. hexadecane, octadecane, or squalane, with C₆-C₃₀Alkyl-substituted aromatic hydrocarbons, e.g. toluene, phenyldodecane, phenyltetradecane, or phenylhexadecane, substituted by C₆-C₂₂Alkyl-substituted phosphines, e.g. trioctylphosphine, substituted by C₆-C₂₂Alkyl-substituted phosphine oxides, e.g. trioctylphosphine oxide, C₁₂-C₂₂An aromatic ether such as phenyl ether, or benzyl ether, or a combination thereof.

In one embodiment of the present application, in order to improve the utilization rate of quantum dots in the quantum dot polymer composite material, in this step, light diffusion particles may be mixed into the polymer material. The light diffusion particles may be inorganic light diffusion particles or organic light diffusion particles, and the application is not limited thereto.

In an embodiment of the present application, the quantum dot and/or the polymer material further includes a hydrocarbon additive. Under normal pressure, the hydrocarbon additive is not volatilized when the high polymer material is in a molten state, namely the boiling point of the hydrocarbon additive is higher than that of the high polymer material. Thus, the hydrocarbon additive will remain in the quantum dot high molecular composite. By adding the hydrocarbon additive with proper content, the dispersibility of the quantum dots in the high polymer material can be effectively increased, and the quantum dots are kept from being greatly agglomerated, so that the stable luminescence performance is ensured. The hydrocarbon additive has the effects that for the condition that the surface of the quantum dot is generally modified with a ligand such as alkylamine, alkyl acid, mercaptan and the like, the quantum dot has stronger hydrophobicity, and the compatibility of the quantum dot and a high polymer material is extremely poor, namely the quantum dot can not be effectively dispersed in the high polymer material. The addition of the hydrocarbon additive can ensure that the quantum dots are well compatible with the high polymer material, so that the quantum dots do not need to be subjected to further surface coating and other steps to improve the dispersibility of the quantum dots in the high polymer material. In addition, special dispersing means such as ultrasound and the like can be avoided in the melting process, and the dispersibility of the quantum dots in the high polymer material can be improved. In one embodiment of the present application, the hydrocarbon additive may be a saturated or unsaturated hydrocarbon, such as white oil. It is to be noted that white oil, also known as paraffin oil or white oil or mineral oil, is obtained by subjecting a mixture of refined liquid hydrocarbons obtained from petroleum, mainly a mixture of saturated naphthenes and paraffins, and crude oil to atmospheric and vacuum fractionation, solvent extraction and dewaxing, and hydrorefining.

S103, extruding the high polymer material to form a quantum dot base film;

in this step, the extruded polymer material includes the polymer material containing the quantum dots in step S102; in addition, the extruded polymeric material may also include a polymeric material without quantum dots. That is, in this step, the quantum dot base film can be formed by directly extruding the polymer material containing quantum dots, and such an extrusion method is generally a single layer extrusion casting method. In addition, a quantum dot base film may be formed by co-extruding a polymer material without quantum dots and a polymer material containing quantum dots, and such an extrusion method is generally a multilayer co-extrusion casting method. Through the mode of multilayer coextrusion casting, the barrier layer is equivalently added on the quantum dot film directly, so that the water oxygen barrier capability of the quantum dot film is improved.

Specifically, quantum dot based films are made by extrusion casting equipment. If the single-layer extrusion casting mode is adopted, the extrusion casting equipment extrudes the molten high polymer material mixed with the quantum dots from a die head and performs casting molding, and the prepared quantum dot base film is of a film structure mixed with the quantum dots; if the multilayer coextrusion casting mode is adopted, for example, a three-layer coextrusion casting mode is taken as an example, the extrusion casting equipment is provided with three die heads, the middle die head is used for extruding the molten high polymer material containing quantum dots, the other two die heads are respectively arranged at two sides of the middle die head and are used for extruding the molten high polymer material without the quantum dots, and finally the high polymer materials extruded by the three die heads are cast and molded into a whole.

In short, the extrusion of the high polymer material is divided into two modes of single-layer extrusion casting and multi-layer co-extrusion casting, when the multi-layer co-extrusion casting mode is adopted, the high polymer material comprises a high polymer material containing quantum dots and a high polymer material without the quantum dots, and the high polymer material containing the quantum dots and the high polymer material without the quantum dots are co-extruded to form the quantum dot base film. When the method is a single-layer extrusion casting method, the high molecular material containing the quantum dots is directly extruded to form the quantum dot base film. The quantum dot high-molecular composite material is processed by an extrusion casting process, so that the water and oxygen blocking capability of the quantum dot film can be well improved, and the risk of destroying and quenching quantum dots in the quantum dot film is reduced. The specific process steps of the single-layer extrusion casting method and the multi-layer coextrusion casting method are common knowledge in the art and are not described herein again.

In the above-described embodiments, the quantum dot base film is formed by casting, but the present invention is not limited thereto, and the quantum dot base film may be formed by uniaxial stretching, biaxial stretching, blow molding, or the like.

In this step, the quantum dot base film is formed to have a thickness of generally 10 μm to 300. mu.m. Of course, the thickness of the specific quantum dot matrix film can be adjusted and set according to actual needs.

Step S104, carrying out corona treatment on the quantum dot base film;

the quantum dot base film formed in step S103 is subjected to corona treatment. In the application, the quantum dot base film is subjected to corona treatment in the middle manufacturing process of the quantum dot base film, so that the hydrocarbon chain and/or the carbon-carbon chain of the high polymer material in the quantum dot base film are broken and recombined, the quantum dot and the high polymer material are rearranged and combined, and the luminous brightness of the quantum dot base film is improved.

The application is different from the prior art in that the prior art only treats the surface of the chemical film by performing corona treatment on various chemical films, and the action is simply to improve the adhesive force of the surface of the chemical film so as to facilitate the subsequent chemical film to be attached to other film layers, while the application directly treats the intermediate product quantum dot base film by performing corona treatment on the intermediate product quantum dot base film so as to change the arrangement and combination structure of quantum dots and high molecular materials in the quantum dot base film, thereby finally improving the luminous brightness of the quantum dot film.

In addition, after the quantum dot base film is subjected to corona treatment, water vapor, oil stain, dust and the like on the surface of the quantum dot base film are removed, and the luminous brightness of the quantum dot film can be improved.

And moreover, the quantum dot base film is subjected to corona treatment, so that the surface roughness of the quantum dot base film is improved, and a water and oxygen blocking layer is conveniently arranged on the quantum dot base film in the follow-up process.

In this step, the time for the corona treatment is 1s to 60s, and specifically, the time for the corona treatment of the quantum dot base film may be determined depending on the thickness of the quantum dot base film and the polymer material.

In this step, the voltage for the corona treatment is generally 5000 to 15000V. Below this voltage range, corona treatment may be ineffective or take too long, while above this voltage range, corona treatment may be damaging to the polymeric material or the quantum dots.

And step S105, preparing the quantum dot film.

The brightness of the quantum dot film prepared by the preparation method is remarkably improved.

In the experimental test of the application, the light-emitting brightness of the quantum dot film which is not subjected to corona treatment in the comparative example is 6100 lumens; and the luminous brightness of the quantum dot film subjected to corona treatment in the embodiment is 7000 lumens, and the luminous brightness is improved by nearly 15%.

Fig. 2 is a flow chart of a method for fabricating a quantum dot film according to another embodiment of the present disclosure. The difference from the above-described method for manufacturing a quantum dot film is that a water-oxygen barrier layer is further provided on the quantum dot film after the quantum dot film is manufactured.

The manufacturing method of the quantum dot film specifically comprises the following steps:

step S201, providing quantum dots and a high polymer material;

in the present application, quantum dots refer to nanoparticles having three-dimensional sizes within 1nm to 100 nm. The shape of the nanoparticles includes, but is not limited to, spherical, ellipsoidal, polyhedral, and the like.

In the application, the size of the quantum dots is preferably 1-15 nm. The quantum dots may be group IIB-VIA quantum dots, group IIIA-VA quantum dots, group IVA-VIA quantum dots, group IVA quantum dots, group IB-IIIA-VIA quantum dots, group VIII-VIA quantum dots, or perovskite quantum dots, but are not limited thereto.

In the present application, the quantum dots may be commercially available or may be synthesized by any method. For example, quantum dots of several nanometers in size can be synthesized by wet chemical processes. In wet chemical processes, the precursors react in an organic solvent to grow the nanocrystal particles, and the organic solvent or ligand compound can coordinate (or bind) to the surface of the nanocrystals, thereby controlling the growth of the nanocrystals.

In the present application, the high molecular material may include at least one of an ethylene-based polymer, a propylene-based polymer, a thiolene-based polymer, an acrylate polymer, a urethane polymer, a carbonate polymer, an epoxy polymer, and a silicone polymer, but is not limited thereto. Specifically, the polymer material may be polyethylene, polyvinylidene fluoride, polyvinyl butyral, polyvinyl alcohol, polystyrene, polypropylene, polymethyl acrylate, polymethyl methacrylate (organic glass), polydecylformamide, polyhexamethylene sebacamide, polyethylene terephthalate glycol-modified polyethylene terephthalate, polyethylene naphthalate, polycarbonate, cellulose acetate butyrate, carnauba wax, polymethylphenylsilicone, polydimethylsiloxane, or the like.

Step S202, mixing quantum dots into at least part of the high polymer material after the high polymer material is in a molten state;

in this application, the polymer material may be a mixture of a plurality of polymers, and to make the polymer material in a molten state, all the polymers in the polymer material are in a molten state.

In an embodiment of the application, in order to increase the mixing uniformity of the quantum dots and the polymer material, the quantum dot high-molecular composite material with better dispersion performance is prepared. In this step, the quantum dot and/or the polymer material further contains a solvent, and the solvent is removed under normal pressure or reduced pressure in a molten state of the polymer material. For example, the solvent is selected from C₆-C₂₂Amine compound, nitrogen-containing heterocyclic compound, and C₆-C₄₀Aliphatic hydrocarbons, C₆-C₃₀Aromatic hydrocarbons, C₆-C₂₂Phosphine oxide compound and C₁₂-C₂₂At least one aromatic ether. Specifically, C₆-C₂₂Primary alkylamines, e.g. hexadecylamine, C₆-C₂₂Secondary alkylamines, e.g. dioctylamine, C₆-C₄₀Tertiary alkyl amines, e.g. trioctylamine, nitrogen-containing heterocycles, e.g. pyridine, C₆-C₄₀Alkenes, e.g. octadecene, C₆-C₄₀Aliphatic hydrocarbons, e.g. hexadecane, octadecane, or squalane, with C₆-C₃₀Alkyl-substituted aromatic hydrocarbons, e.g. toluene, phenyldodecane, phenyltetradecane, or phenylhexadecane, substituted by C₆-C₂₂Alkyl-substituted phosphines, e.g. trioctylphosphine, substituted by C₆-C₂₂Alkyl-substituted phosphine oxides, e.g. trioctylphosphine oxide, C₁₂-C₂₂An aromatic ether such as phenyl ether, or benzyl ether, or a combination thereof.

In one embodiment of the present application, in order to improve the utilization rate of quantum dots in the quantum dot polymer composite material, in this step, light diffusion particles may be mixed into the polymer material. The light diffusion particles may be inorganic light diffusion particles or organic light diffusion particles, and the application is not limited thereto.

In an embodiment of the present application, the quantum dot and/or the polymer material further includes a hydrocarbon additive. Under normal pressure, the hydrocarbon additive is not volatilized when the high polymer material is in a molten state, namely the boiling point of the hydrocarbon additive is higher than that of the high polymer material. Thus, the hydrocarbon additive will remain in the quantum dot high molecular composite. By adding the hydrocarbon additive with proper content, the dispersibility of the quantum dots in the high polymer material can be effectively increased, and the quantum dots are kept from being greatly agglomerated, so that the stable luminescence performance is ensured. The hydrocarbon additive has the effects that for the condition that the surface of the quantum dot is generally modified with a ligand such as alkylamine, alkyl acid, mercaptan and the like, the quantum dot has stronger hydrophobicity, and the compatibility of the quantum dot and a high polymer material is extremely poor, namely the quantum dot can not be effectively dispersed in the high polymer material. The addition of the hydrocarbon additive can ensure that the quantum dots are well compatible with the high polymer material, so that the quantum dots do not need to be subjected to further surface coating and other steps to improve the dispersibility of the quantum dots in the high polymer material. In addition, special dispersing means such as ultrasound and the like can be avoided in the melting process, and the dispersibility of the quantum dots in the high polymer material can be improved. In one embodiment of the present application, the hydrocarbon additive may be a saturated or unsaturated hydrocarbon, such as white oil. It is to be noted that white oil, also known as paraffin oil or white oil or mineral oil, is obtained by subjecting a mixture of refined liquid hydrocarbons obtained from petroleum, mainly a mixture of saturated naphthenes and paraffins, and crude oil to atmospheric and vacuum fractionation, solvent extraction and dewaxing, and hydrorefining.

Step S203, extruding the high polymer material to form a quantum dot base film;

in this step, the extruded polymer material includes the polymer material containing the quantum dots in step S202; in addition, the extruded polymeric material may also include a polymeric material without quantum dots. That is, in this step, the quantum dot base film can be formed by directly extruding the polymer material containing quantum dots, and such an extrusion method is generally a single layer extrusion casting method. In addition, a quantum dot base film may be formed by co-extruding a polymer material without quantum dots and a polymer material containing quantum dots, and such an extrusion method is generally a multilayer co-extrusion casting method. Through the mode of multilayer coextrusion casting, the barrier layer is equivalently added on the quantum dot film directly, so that the water oxygen barrier capability of the quantum dot film is improved.

Specifically, quantum dot based films are made by extrusion casting equipment. If the single-layer extrusion casting mode is adopted, the extrusion casting equipment extrudes the molten high polymer material mixed with the quantum dots from a die head and performs casting molding, and the prepared quantum dot base film is of a film structure mixed with the quantum dots; if the multilayer coextrusion casting mode is adopted, for example, a three-layer coextrusion casting mode is taken as an example, the extrusion casting equipment is provided with three die heads, the middle die head is used for extruding the molten high polymer material containing quantum dots, the other two die heads are respectively arranged at two sides of the middle die head and are used for extruding the molten high polymer material without the quantum dots, and finally the high polymer materials extruded by the three die heads are cast and molded into a whole.

In the above-described embodiments, the quantum dot base film is formed by casting, but the present invention is not limited thereto, and the quantum dot base film may be formed by uniaxial stretching, biaxial stretching, blow molding, or the like.

Step S204, carrying out corona treatment on the quantum dot base film;

the quantum dot base film formed in step S203 is subjected to corona treatment. In the application, the quantum dot base film is subjected to corona treatment in the middle manufacturing process of the quantum dot base film, so that the hydrocarbon chain and/or the carbon-carbon chain of the high polymer material in the quantum dot base film are broken and recombined, the quantum dot and the high polymer material are rearranged and combined, and the luminous brightness of the quantum dot base film is improved.

In addition, after the quantum dot base film is subjected to corona treatment, water vapor, oil stain, dust and the like on the surface of the quantum dot base film are removed, and the luminous brightness of the quantum dot film can be improved.

And finally, the quantum dot base film is subjected to corona treatment, so that the surface roughness of the quantum dot base film is improved, and the quantum dot base film is conveniently attached or coated with a water-oxygen barrier layer.

And S205, preparing the quantum dot film.

By the manufacturing method of the quantum dot film, the finally obtained luminous brightness of the quantum dot film is remarkably improved.

And S206, arranging a water-oxygen barrier layer on the quantum dot film.

In this step, a water and oxygen barrier layer is provided on the quantum dot film, thereby further improving the water and oxygen barrier capability of the quantum dot film. For example, a common water and oxygen barrier layer is a PET layer, and of course, an inorganic barrier layer including titanium oxide nanoparticles, silicon oxide nanoparticles, aluminum oxide nanoparticles, or the like may be further deposited on the quantum dot film before the PET layer is attached, and the inorganic barrier layer may be formed by evaporation. The formation of the inorganic barrier layer is well known to those skilled in the art and will not be described herein.

In one embodiment of the present application, an inorganic barrier layer may also be deposited on the PET layer to form a water-oxygen barrier layer in which the inorganic barrier is mixed with the organic barrier.

In an embodiment of the present application, in order to reduce the thickness of the quantum dot film, a water-oxygen barrier layer may be directly coated on the quantum dot film. Coating water oxygen barrier layer probably is poor than the ability of laminating PET layer or the oxygen of blocking water of deposit inorganic barrier layer, but what the processing procedure of quantum dot membrane adopted in this application is that the mode of melting curtain coating film-forming makes, and the oxygen ability of blocking water of quantum dot membrane itself has obtained fine promotion, therefore scribble the requirement that one deck water oxygen barrier layer can satisfy the oxygen of blocking water again on the quantum dot membrane to it glues technologies such as extra laminating and impression more need not carry out. The cost of the quantum dot film can also be greatly reduced by coating the water-oxygen barrier layer.

It can be understood that the quantum dot film is laminated with the barrier layer, and the water and oxygen barrier layer can be coated on the quantum dot film at the same time, so that the two layers are not in conflict with each other, and the laminated barrier layer and the coating water and oxygen barrier layer can be combined together for use according to actual needs.

As shown in fig. 3, which is a schematic structural diagram of a quantum dot film according to an embodiment of the present disclosure, the quantum dot film includes a quantum dot layer 102 and a water-oxygen barrier layer 101, and the quantum dot layer 102 is sandwiched between the two water-oxygen barrier layers 101 to form a "sandwich structure". The quantum dot film is obtained by a method for manufacturing a quantum dot film, the method for manufacturing the quantum dot film comprising: providing quantum dots and a high polymer material; step two, mixing quantum dots into the high polymer material after the high polymer material is in a molten state; extruding the high polymer material to form a quantum dot base film; step four, carrying out corona treatment on the quantum dot base film; step five, preparing a quantum dot film; and step six, attaching a water-oxygen barrier layer on the quantum dot film. In this embodiment, the quantum dot film is manufactured after the quantum dot base film is subjected to corona treatment, so that the luminance of the quantum dot film is obviously improved.

In the experimental test, the light-emitting brightness of the quantum dot film which is not subjected to the corona treatment in the comparative example is 6000 lumens; in the embodiment, the light-emitting brightness of the quantum dot film subjected to corona treatment is 6800 lumens, and the light-emitting brightness is improved by nearly 14%.

In this embodiment, the quantum dot layer 102 in the quantum dot film is formed by a single layer extrusion casting method, and the water and oxygen barrier layers 101 are attached to both sides of the quantum dot layer 102. In another embodiment of the present application, a material with water and oxygen barrier ability may also be disposed on the quantum dot layer 102 in a coating manner, so as to function as a water and oxygen barrier layer, which may reduce the thickness of the quantum dot film and reduce the cost of the quantum dot film.

As shown in fig. 4, which is a schematic structural diagram of a quantum dot film in another embodiment of the present application, the quantum dot film includes a quantum dot-containing polymer layer 202, a quantum dot-free polymer layer 203, and a water-oxygen barrier layer 201. The quantum dot film is obtained by a method for manufacturing a quantum dot film, the method comprising: providing quantum dots and a high polymer material; step two, mixing quantum dots into the high polymer material after the high polymer material is in a molten state; extruding the high polymer material to form a quantum dot base film; step four, carrying out corona treatment on the quantum dot base film; step five, preparing a quantum dot film; and sixthly, coating a water-oxygen barrier layer on the quantum dot film. In this embodiment, the quantum dot film forms an integral structure of the quantum dot-containing polymer layer 202 and the quantum dot-free polymer layer 203 by means of multilayer coextrusion casting, and then the water and oxygen barrier layers 201 are coated on the upper and lower sides of the integral structure, and the quantum dot-free polymer layer 203 is formed on the quantum dot-containing polymer layer 202 in advance by means of multilayer coextrusion casting, and the quantum dot-free polymer layer 203 plays a role in protecting the quantum dot from water and oxygen, thereby further improving the water and oxygen barrier capability of the quantum dot film.

As shown in fig. 5, which is a schematic structural diagram of a backlight module according to an embodiment of the present invention, the backlight module includes a blue light source (not shown), a light guide plate 301 and a quantum dot film 303, the light guide plate 301 outputs blue light 302, and after the blue light 302 enters the quantum dot film 303, the quantum dot film 303 converts the blue light into red light and green light, and mixes the red light and the green light with the unconverted blue light to form a white backlight. The quantum dot film 303 is prepared by the following preparation method of the quantum dot film, and the method comprises the following steps: providing quantum dots and a high polymer material; step two, mixing quantum dots into the high polymer material after the high polymer material is in a molten state; extruding the high polymer material to form a quantum dot base film; step four, carrying out corona treatment on the quantum dot base film; and step five, preparing the quantum dot film. In the middle manufacturing process of the quantum dot film, the quantum dot base film is subjected to corona treatment, so that the carbon-hydrogen chain and/or the carbon-carbon chain of the high polymer material in the quantum dot base film are broken and recombined, and the quantum dot and the high polymer material are rearranged and combined, so that the luminous brightness of the quantum dot base film is improved; in addition, after the quantum dot base film is subjected to corona treatment, water vapor, oil stain, dust and the like on the surface of the quantum dot base film are removed, the luminous brightness of the quantum dot film can be improved, and finally, the quantum dot base film is subjected to corona treatment, so that the roughness of the surface of the quantum dot base film is improved, and the quantum dot base film can be conveniently attached to or coated with a water-oxygen blocking layer.

Quantum dot films according to some exemplary embodiments of the present application are described in more detail with reference to the following examples; however, the exemplary embodiments of the present application are not limited thereto.