Display panel and manufacturing method thereof, and display device

Abstract

The present application discloses a display panel and a preparation method thereof, and a display device. The display panel includes a substrate and a light-emitting unit located on the substrate, the light-emitting unit includes a first primary color light-emitting unit, the first primary color light-emitting unit includes a first light-emitting element and a first light conversion unit located on the side of the first light-emitting element away from the substrate, the first light conversion unit includes a mixture of a first light conversion material and a thermal conductive material, and the first light conversion material and the thermal conductive material are adhered together by electrostatic attraction, then, in the process of the first light conversion material converting light, its own heat can be quickly spread through the adhered thermal conductive material, and then transferred to the packaging shell, that is, the heat transfer path from the inside of the first light conversion material to the packaging shell is strengthened, so that the display panel can dissipate heat efficiently.

Description

Technical Field

[0001] The present application relates to the field of display technology, and in particular to a display panel and a method for preparing the same, and a display device. Background Art

[0002] With the development of display technology, people's requirements for display quality are getting higher and higher. By integrating a large number of arrayed Micro-LED and other light-emitting devices on an active addressing drive substrate, each light-emitting device can be individually controlled and lit, so that the resolution of the image output by the display panel can reach the theoretical maximum. However, each light-emitting device generates heat, so the heat dissipation problem of the display panel is becoming more and more serious. Now there is an urgent need for a display panel that can dissipate heat efficiently. Summary of the invention

[0003] In order to solve the above technical problems, the embodiments of the present application provide a display panel and a method for manufacturing the same, and a display device, so as to provide a display panel capable of efficiently dissipating heat.

[0004] To achieve the above objectives, the present application provides the following technical solutions:

[0005] A display panel, comprising:

[0006] substrate;

[0007] A light-emitting unit, the light-emitting unit is located on the substrate, the light-emitting unit includes a first primary color light-emitting unit, the first primary color light-emitting unit includes a first light-emitting element and a first light conversion unit located on a side of the first light-emitting element away from the substrate, the first light conversion unit is used to convert light emitted by the first light-emitting element into first primary color visible light;

[0008] The first light conversion unit includes a mixture of a first light conversion material and a heat conductive material, and the first light conversion material and the heat conductive material adhere together through electrostatic attraction.

[0009] A method for preparing a display panel, comprising:

[0010] providing a substrate;

[0011] A light-emitting unit is formed on the substrate, the light-emitting unit includes a first primary color light-emitting unit, the first primary color light-emitting unit includes a first light-emitting element and a first light-converting unit located on a side of the first light-emitting element away from the substrate, the first light-converting unit is used to convert light emitted by the first light-emitting element into first primary color visible light;

[0012] The formation process of the first light conversion unit includes:

[0013] Processing the first photoconversion material so that the first photoconversion material carries a first type of charge;

[0014] The thermal conductive material is processed so that the thermal conductive material carries a second type of charge, and the second type of charge is opposite in electrical properties to the first type of charge;

[0015] Mixing the first photoconversion material carrying the first type of charge and the thermal conductive material carrying the second type of charge evenly, so that the first photoconversion material and the thermal conductive material adhere to each other through electrostatic attraction of positive and negative charges;

[0016] The first light conversion unit is formed by using the first light conversion material and the heat conductive material that are uniformly mixed.

[0017] A display device comprises the above-mentioned display panel.

[0018] Compared with the prior art, the above technical solution has the following advantages:

[0019] In the display panel provided in the embodiment of the present application, the first light conversion unit includes a mixture of a first light conversion material and a thermal conductive material, and the first light conversion material and the thermal conductive material are adhered together by electrostatic attraction. Then, in the process of the first light conversion material converting light, its own heat can be quickly spread through the adhered thermal conductive material, and then transferred to the packaging shell and dissipated. It can be seen that the display panel provided in the embodiment of the present application can dissipate heat efficiently.

[0020] Furthermore, the heat inside the first light conversion material is rapidly transferred to the packaging shell through the adhered thermal conductive material, thereby strengthening the heat transfer path from the first light conversion material to the packaging shell, thereby effectively alleviating the local heat accumulation of the first light conversion material and avoiding the problem of fluorescence quenching caused by internal heat accumulation in the first light conversion material, thereby affecting the light conversion efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0022] Figure 1 A schematic diagram of the structure of a display panel provided by an embodiment of the present application;

[0023] Figure 2 A schematic diagram of a display panel provided in an embodiment of the present application, in which a first light conversion material carrying a positive charge and a heat conductive material carrying a negative charge in a first light conversion unit are adhered together by electrostatic attraction;

[0024] Figure 3A schematic diagram of a display panel provided in an embodiment of the present application, in which a first light conversion material carrying a negative charge and a heat conductive material carrying a positive charge in a first light conversion unit are adhered together by electrostatic attraction;

[0025] Figure 4 A schematic diagram of the structure of a display panel provided in another embodiment of the present application;

[0026] Figure 5 A schematic diagram of the structure of a display panel provided in yet another embodiment of the present application;

[0027] Figure 6 A schematic diagram of the structure of a display panel provided in yet another embodiment of the present application;

[0028] Figure 7 A schematic diagram of a process for preparing a display panel provided in one embodiment of the present application;

[0029] Figure 8 A schematic flow chart of a process for forming a first light conversion unit in a method for manufacturing a display panel provided in an embodiment of the present application;

[0030] Fig. 9 A schematic diagram of the structure of a display device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0031] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0032] In the following description, many specific details are set forth to facilitate a full understanding of the present application, but the present application may also be implemented in other ways different from those described herein, and those skilled in the art may make similar generalizations without violating the connotation of the present application. Therefore, the present application is not limited to the specific embodiments disclosed below.

[0033] Secondly, the present application is described in detail with reference to the schematic diagram. When describing the embodiments of the present application in detail, for the sake of convenience, the cross-sectional diagrams showing the device structure will not be partially enlarged according to the general scale, and the schematic diagrams are only examples, which should not limit the scope of protection of the present application. In addition, in actual production, the three-dimensional dimensions of length, width and depth should be included.

[0034] As described in the background technology section, there is an urgent need for a display panel that can efficiently dissipate heat.

[0035] The inventors have found that current conventional heat dissipation technologies such as air cooling, liquid cooling, and thermal interface materials can only strengthen the heat transfer path from the packaging shell to the external heat dissipation device. However, in the light-emitting unit inside the display panel, its light conversion material will generate heat when converting the color of light. This heat will accumulate inside the light conversion material, which can easily cause local hot spots and induce fluorescence quenching, thereby affecting the light conversion efficiency of the light conversion material. Conventional heat dissipation technologies such as air cooling, liquid cooling, and thermal interface materials cannot strengthen the heat transfer path from the inside of the light conversion material to the packaging shell, that is, the heat inside the light conversion material cannot be quickly transferred to the packaging shell. This is the fundamental reason why heat accumulation inside the light conversion material causes fluorescence quenching.

[0036] In view of this, an embodiment of the present application provides a display panel, such as Figure 1 As shown, the display panel includes:

[0037] substrate 100;

[0038] A light-emitting unit 200, the light-emitting unit 200 is located on the substrate 100, and the light-emitting unit 200 includes a first primary color light-emitting unit 210, the first primary color light-emitting unit 210 includes a first light-emitting element 211 and a first light conversion unit 212 located on a side of the first light-emitting element 211 away from the substrate 100, and the first light conversion unit 212 is used to convert the light emitted by the first light-emitting element 211 into first primary color visible light;

[0039] Among them, Figure 2 and Figure 3 As shown, the first light conversion unit 212 includes a mixture of a first light conversion material 10 and a thermal conductive material 20, and the first light conversion material 10 and the thermal conductive material 20 are adhered together by electrostatic attraction.

[0040] Specific, combined Figure 1 , Figure 2 and Figure 3 As shown, in the first light conversion unit 212, the first light conversion material 10 is used to convert the light emitted by the first light emitting element 211 into the first primary color visible light. In the process of the first light conversion material 10 converting the light, its own heat can be quickly spread through the adhered thermal conductive material 20, and then transferred to the package shell to dissipate. It can be seen that the display panel provided by the embodiment of the present application can dissipate heat efficiently. In addition, the heat inside the first light conversion material 10 is quickly transferred to the package shell through the adhered thermal conductive material 20, that is, the heat transfer path from the first light conversion material 10 to the package shell is strengthened, thereby effectively alleviating the local heat accumulation of the first light conversion material 10, and avoiding the problem that the first light conversion material 10 causes fluorescence quenching due to its internal heat accumulation, thereby affecting the light conversion efficiency.

[0041] Optionally, the first primary color visible light may be any one of red light, green light and blue light. The present application does not limit the specific primary color visible light of the first primary color visible light, which depends on specific circumstances.

[0042] It should be noted that in the first light conversion unit 212, the mixed first light conversion material 10 and the thermal conductive material 20 are adhered together by electrostatic attraction, so that the heat generated by the first light conversion material 10 can be quickly spread through the thermal conductive material 20 and transferred to the packaging shell, which is safer, more reliable and less costly.

[0043] Optionally, in one embodiment of the present application, Figure 2 and Figure 3 As shown, the first photoconversion material 10 carries a first type of charge, and the thermal conductive material 20 carries a second type of charge, and the first type of charge and the second type of charge are electrically opposite, so that the first photoconversion material 10 and the thermal conductive material 20 adhere together through electrostatic attraction between positive and negative charges.

[0044] For example, Figure 2 As shown, the first photoconversion material 10 carries positive charge and the thermal conductive material 20 carries negative charge; or Figure 3 As shown, the first light conversion material 10 carries negative charges, and the thermal conductive material 20 carries positive charges.

[0045] According to the principle of electrostatic induction, when a charged object and an uncharged object are close to each other, the interaction between the charges will cause the two objects to adhere to each other through electrostatic attraction. Therefore, optionally, in another embodiment of the present application, the first photoconversion material 10 or the thermal conductive material 20 carries a charge, that is, one of the first photoconversion material 10 and the thermal conductive material 20 carries a charge, and the other material does not carry a charge. The material that does not carry a charge will be electrostatically induced by the charge carried by the charged material, causing the charge inside the material to be redistributed, thereby causing the first photoconversion material 10 and the thermal conductive material 20 to adhere to each other through electrostatic attraction.

[0046] It can be understood that when the first photoconversion material 10 carries the first type of charge and the thermal conductive material 20 carries the second type of charge, the electrostatic force between the two is greater than when one of the first photoconversion material 10 and the thermal conductive material 20 carries a charge and the other does not carry a charge, that is, when the first photoconversion material 10 carries the first type of charge and the thermal conductive material 20 carries the second type of charge, the electrostatic adhesion between the first photoconversion material 10 and the thermal conductive material 20 is stronger.

[0047] Optionally, in one embodiment of the present application, the particle size of the first photoconversion material 10 is 1 nm-10 nm, including the end value, that is, the particle size of the first photoconversion material 10 is less than or equal to the Bohr exciton radius. Figure 2 and Figure 3 As shown, if the particle size of the thermal conductive material 20 is too large, although the heat transfer from the inside of the first light conversion material 10 to the package shell can be enhanced, it is likely that the light absorption characteristics and scattering effect of the thermal conductive material 20 will cause the light conversion efficiency of the first light conversion material 10 to decay. Therefore, in this embodiment, the particle size of the thermal conductive material does not exceed 300nm to reduce the decay of the light conversion efficiency of the first light conversion material 10, thereby reducing the impact on optical performance while achieving efficient heat transfer. Preferably, the particle size of the thermal conductive material 20 does not exceed 100nm to further reduce the impact on optical performance while achieving efficient heat transfer.

[0048] Among them, the first light conversion material 10 can be a quantum dot material, and the quantum dot material can be a cadmium-based quantum dot material (such as CdSe, CdS, etc.), a cadmium-free quantum dot material (such as InP, ZnO, etc.) or a perovskite quantum dot material (APbX3, where X = Cl, Br, I, etc.). At this time, quantum dot materials with different particle sizes have different fluorescence effects and can laser visible light of different primary colors. Compared with traditional fluorescent dyes, the size of quantum dot materials is adjustable, and the emission and excitation bandwidths of fluorescence cover the spectral region from ultraviolet to infrared. The emission spectrum is narrow and symmetrical, has excellent light stability, and displays a wider color gamut.

[0049] The thermal conductive material may be boron nitride quantum dot material, graphene quantum dot material, nano pure copper powder material, nano aluminum oxide material, carbon nano tube material or nano diamond material.

[0050] It should be noted that nanodiamond materials have ultra-high thermal conductivity (2000W·m -1 ·K -1 ), the material particle size is 5nm-100nm, the light transmittance is high, and the stability is also good. Therefore, after the nano diamond material is filled into the first light conversion material 10 as the heat conductive material 20, efficient heat transfer can be achieved, and the light conversion efficiency of the first light conversion material 10 is almost not affected, that is, the optical performance is almost not affected. In addition, most of the nano diamond materials are single crystals, and their surface morphology is a relatively regular sphere or quasi-sphere, so that the nano diamond material has a large specific surface area, so that it has a strong surface activity, and can adsorb a large number of impurity atoms or groups, that is, it is easy for the nano diamond material to carry positive or negative charges, so as to adhere to the first light conversion material 10 through electrostatic attraction.

[0051] It should also be noted that the graphene material itself is black and has a large particle size. If it is directly filled in the first light conversion material 10, it may affect the light conversion efficiency of the first light conversion material 10 and affect the optical performance. Therefore, in this embodiment, the graphene material is used to make a graphene quantum dot material. Since the size of the graphene quantum dot material becomes nanometer level, the graphene quantum dot material is transparent, so it can be used as a thermal conductive material 20 to be filled into the first light conversion material 10 for heat transfer, thereby reducing the attenuation of the light conversion efficiency of the first light conversion material 10 and avoiding affecting the optical performance.

[0052] In addition, the sizes of boron nitride quantum dot materials, nano pure copper powder materials, nano aluminum oxide materials, and carbon nanotube materials are all below 300 nm. When they are filled into the first light conversion material 10 as thermal conductive materials 20, efficient heat transfer can be achieved while reducing the impact on optical performance.

[0053] Specifically, the formation process of the first light conversion unit 212 is described by taking the first light conversion material 10 as a quantum dot material and the thermal conductive material 20 as a nano-diamond material as an example. During the production process, the quantum dot material can be pre-coated with a surface ligand containing a cation (containing Cd 2+ / Zn 2+ / Ag + The method comprises the steps of: preparing a nano-diamond material with a positive charge and treating the nano-diamond material with an anionic surfactant (such as a carboxylate, a sulfonate, a sulfate ester, a phosphate ester, etc.) in advance so that the quantum dot material carries a positive charge, and treating the nano-diamond material with an anionic surfactant (such as a carboxylate, a sulfonate, a sulfate ester, a phosphate ester, etc.) in advance so that the nano-diamond material carries a negative charge; then, the quantum dot material carrying the positive charge and the nano-diamond material carrying the negative charge are uniformly mixed, for example, by stirring to make them uniformly mixed, so that the quantum dot material and the nano-diamond material are spontaneously adhered together by electrostatic attraction between the positive and negative charges; finally, the first light conversion unit is formed using the uniformly mixed quantum dot material and nano-diamond material.

[0054] To achieve efficient heat transfer while reducing the impact on optical performance, the particle size and material of the thermally conductive material in the first light conversion unit may be limited as described above, or the weight ratio of the thermally conductive material in the first light conversion unit may be limited.

[0055] Specifically, in one embodiment of the present application, in the first light conversion unit 212 , the weight ratio of the thermal conductive material is 0.01-0.2, including endpoint values.

[0056] In this embodiment, if the first light conversion unit is set to 100 parts by weight, the thermal conductive material is 1-20 parts by weight, and the first light conversion material is 80-99 parts by weight, so as to prevent the weight proportion of the thermal conductive material in the first light conversion unit from being too large, causing the light conversion efficiency of the first light conversion material to be attenuated and affecting the optical performance.

[0057] It should be noted that in the above embodiments, reference Figure 1 As shown, the first light conversion unit 212 is located on the side of the first light emitting element 211 away from the substrate 100. Optionally, in one embodiment of the present application, continue as Figure 1 As shown, the display panel also includes:

[0058] The color resist unit 300 includes a first color resist unit 310, which is located on a side of the first primary color light-emitting unit 210 facing away from the substrate 100. The first light conversion unit 212 in the first primary color light-emitting unit 210 is attached to the surface of the first color resist unit 310 facing the substrate 100 and is spaced apart from the first light-emitting element 211.

[0059] In this embodiment, the first light conversion unit 212 and the first light emitting element 211 are disposed separately, and the first light conversion unit 212 and the first color resist unit 310 are aligned and attached together.

[0060] Considering that the first light-emitting element 211 also generates heat, and the air between the first light-emitting element 211 and the first light-emitting element 212 is a poor conductor of heat, therefore, if the first light-emitting element 212 is close to the first light-emitting element 211 and the distance between the two is small, then the thermal conductive material 20 in the first light-emitting element 212 can not only transfer the heat of the first light-emitting element 10, but also transfer the heat of the first light-emitting element 211.

[0061] To this end, in one embodiment of the present application, Figure 4 As shown, the first light conversion unit 212 is no longer attached to the first color resist unit 310, but a distance d between the first light emitting element 211 and the first light conversion unit 212 is set to be no more than 5 μm in a direction perpendicular to the substrate 100, so that the thermal conductive material 20 in the first light conversion unit 212 can transfer the heat of the first light conversion material 10 and the heat of the first light emitting element 211 at the same time.

[0062] Preferably, in one embodiment of the present application, Figure 5As shown, the first light conversion unit 212 is directly integrated on the surface of the first light-emitting element 211 facing away from the substrate 100, that is, the surface of the first light conversion unit 212 facing the substrate 100 is in contact with the surface of the first light-emitting element 211 facing away from the substrate 100, that is, the first light conversion unit 212 and the first light-emitting element 211 are in close contact, which is more conducive to the thermal conductive material 20 in the first light conversion unit 212 to quickly transfer the heat of the first light-emitting element 211 to the packaging shell, that is, while strengthening the heat transfer path from the first light-emitting element 211 to the packaging shell, it also further strengthens the heat transfer path from the first light-emitting element 211 to the packaging shell.

[0063] We know that the current excitation light sources for incident quantum dot materials mainly use blue LEDs and ultraviolet LEDs. For the two primary colors of red and green, when using blue LEDs or ultraviolet LEDs as the excitation light sources, the emitted light of the excitation light source needs to be incident on the quantum dot material for color conversion. For the primary color blue, when using blue LEDs as the excitation light source, the emitted light of the excitation light source can be directly emitted without setting up quantum dot materials. When using ultraviolet LEDs as the excitation light source, the emitted light of the excitation light source needs to be incident on the quantum dot material for color conversion.

[0064] The inventors have found that when ultraviolet LEDs are used as excitation light sources, the laser efficiency of quantum dot materials is higher than when blue LEDs are used as excitation light sources, and the corresponding color gamut range is also larger. This is because when blue LEDs are excited, part of the light will pass through the quantum dot material and be emitted directly, while when ultraviolet LEDs are excited, less light is directly transmitted. Therefore, in order to achieve the same brightness, when blue LEDs are used as excitation light sources, more photons need to be emitted than when ultraviolet LEDs are used as excitation light sources, which means higher power consumption is required, and the corresponding quantum dot materials will generate more heat. However, when blue LEDs excite quantum dot materials, only red and green need to undergo color conversion through quantum dot materials, while blue can be emitted directly without the need to set up quantum dot materials, which means that the use of one type of quantum dot material can be reduced, and there will be no ultraviolet light leakage.

[0065] To this end, optionally, in one embodiment of the present application, Figure 1 As shown, the light-emitting unit 200 further includes a second primary color light-emitting unit 220, the second primary color light-emitting unit 220 includes a second light-emitting element 221 and a second light-converting unit 222 located on a side of the second light-emitting element 221 away from the substrate 100, and the second light-converting unit 222 is used to convert the light emitted by the second light-emitting element 221 into a second primary color visible light;

[0066] Wherein, the second light conversion unit 222 includes a mixture of a second light conversion material 30 and a heat conductive material 20, and the second light conversion material 30 and the heat conductive material 20 adhere together by electrostatic attraction;

[0067] The second light emitting element 221 is a blue light LED, the first light emitting element 211 is an ultraviolet light LED, and the weight proportion of the heat conductive material in the second light conversion unit 222 is greater than the weight proportion of the heat conductive material in the first light conversion unit 212 .

[0068] In the present embodiment, the second primary color light emitting unit 220 using a blue light LED as an excitation light source requires a higher power consumption of the blue light LED to achieve the same brightness compared to the first primary color light emitting unit 210 using an ultraviolet light LED as an excitation light source. As a result, the heat generated by the blue light LED is greater, and the heat generated by the second light conversion material 30 in the second light conversion unit 222 is also greater. Therefore, a larger weight proportion of the thermal conductive material in the second light conversion unit 222 is set so that when the blue light LED is used as a laser light source, more heat generated by the second light conversion material 30 in the second light conversion unit 222 is quickly transferred to the packaging shell, thereby effectively alleviating the internal heat accumulation of the second light conversion material 30.

[0069] Furthermore, if Figure 4 and Figure 5 As shown, the distance between the second light emitting element 221 and the second light conversion unit 222 may be set to be no more than 5 μm in the direction perpendicular to the substrate 100. Preferably, the second light emitting element 221 and the second light conversion unit 222 are arranged to be in contact with each other in the direction perpendicular to the substrate 100. At this time, the thermal conductive material 20 in the second light conversion unit 222 can also quickly transfer more heat generated by the blue LED to the package shell, further compensating for the disadvantages of the blue LED as a laser light source.

[0070] It can be seen that the display panel provided in the embodiment of the present application fills the thermal conductive material in the light conversion material, and the light conversion material and the thermal conductive material adhere together through electrostatic attraction, so that more heat generated by the blue light LED itself and more heat generated by its corresponding quantum dot material can be quickly transferred to the packaging shell, which makes up for the disadvantages of the blue light LED as an excitation light source, thereby making full use of the advantages of the blue light LED as a laser light source.

[0071] Considering that the thermal stability of red light Micro-LED is poor, when the temperature rises, the luminous efficiency of red light Micro-LED decreases more significantly than that of green light Micro-LED and blue light Micro-LED. Therefore, optionally, in another embodiment of the present application, Figure 1As shown, the light-emitting unit 200 further includes a second primary color light-emitting unit 220, the second primary color light-emitting unit 220 includes a second light-emitting element 221 and a second light-converting unit 222 located on a side of the second light-emitting element 221 away from the substrate 100, and the second light-converting unit 222 is used to convert the light emitted by the second light-emitting element 221 into a second primary color visible light;

[0072] Wherein, the second light conversion unit 222 includes a mixture of a second light conversion material 30 and a heat conductive material 20, and the second light conversion material 30 and the heat conductive material 20 adhere together by electrostatic attraction;

[0073] The second primary color visible light is red light, the first primary color visible light is green light or blue light, and the weight proportion of the thermal conductive material 20 in the second light conversion unit 222 is greater than the weight proportion of the thermal conductive material 20 in the first light conversion unit 212 .

[0074] In this embodiment, the weight proportion of the thermally conductive material 20 in the light conversion unit corresponding to red light (i.e., the second light conversion unit 222) is set to be greater than the weight proportion of the thermally conductive material 20 in the light conversion unit corresponding to green light or blue light (i.e., the first light conversion unit 212), so that the heat in the light conversion unit corresponding to red light can be transferred to the packaging shell faster and more, thereby improving the stability of the light conversion unit corresponding to red light.

[0075] Since the light-emitting unit corresponding to red light (i.e., the second primary color light-emitting unit 220) has poor thermal stability, and it can be known from the above that when a blue light LED is used as an excitation light source, the excitation heat generation of the quantum dot material is greater than when an ultraviolet light LED is used as an excitation light source, therefore, the second light-emitting element 221 in the red light-emitting unit (i.e., the second primary color light-emitting unit 220) is preferably an ultraviolet light LED. In this embodiment, the weight proportion of the heat-conducting material 20 in the light conversion unit corresponding to red light (i.e., the second light conversion unit 222) is set to be greater than the weight proportion of the heat-conducting material 20 in the light conversion unit corresponding to green light or blue light (i.e., the first light conversion unit 212), so that the heat in the light conversion unit corresponding to red light (i.e., the second light conversion unit 222) can be transferred to the package shell faster and more, therefore, the light-emitting element (i.e., the second light-emitting element 221) in the light conversion unit corresponding to red light (i.e., the second light conversion unit 222) can also be set to a blue light LED.

[0076] It is understandable that, in another embodiment of the present application, reference Figure 1 As shown, the light-emitting unit 200 further includes a second primary color light-emitting unit 220, the second primary color light-emitting unit 220 includes a second light-emitting element 221 and a second light-converting unit 222 located on a side of the second light-emitting element 221 away from the substrate 100, and the second light-converting unit 222 is used to convert the light emitted by the second light-emitting element 221 into a second primary color visible light;

[0077] Wherein, the second light conversion unit 222 includes a mixture of a second light conversion material 30 and a heat conductive material 20, and the second light conversion material 30 and the heat conductive material 20 adhere together by electrostatic attraction;

[0078] The weight ratio of the thermal conductive material 20 in the second light conversion unit 222 is equal to the weight ratio of the thermal conductive material 20 in the first light conversion unit 212 .

[0079] In this embodiment, the weight ratio of the heat conductive material 20 in the second light conversion unit 222 and the weight ratio of the heat conductive material 20 in the first light conversion unit 212 are set equal, so that the manufacturing process is simpler.

[0080] It should be noted that, in the present embodiment, the specific primary colors of the first primary color visible light and the second primary color visible light are not limited, that is, the first primary color visible light and the second primary color visible light can be red light and green light, or red light and blue light, or green light and blue light, or any other two colors of light.

[0081] In the above three embodiments, the first primary color light emitting unit 210 and the second primary color light emitting unit 220 are isolated from each other by a barrier 400 .

[0082] In the above three embodiments, the electrostatic attraction and adhesion between the second light conversion material 30 and the thermal conductive material 20 is the same as the electrostatic attraction and adhesion between the first light conversion material 10 and the thermal conductive material 20, which will not be described in detail here.

[0083] In the above three embodiments, the particle sizes of the first light conversion material 10 and the second light conversion material 30 can be 1 nm-10 nm, including end values; the particle size of the thermal conductive material 20 does not exceed 300 nm, preferably does not exceed 100 nm.

[0084] Specifically, the first light conversion material 10 and the second light conversion material 30 can both be quantum dot materials, and the quantum dot materials can be cadmium-based quantum dot materials (such as CdSe, CdS, etc.), cadmium-free quantum dot materials (such as InP, ZnO, etc.) or perovskite quantum dot materials (APbX3, where X = Cl, Br, I, etc.).

[0085] The heat conducting material 20 may be boron nitride quantum dot material, graphene quantum dot material, nano pure copper powder material, nano aluminum oxide material, carbon nano tube material or nano diamond material. Preferably, the heat conducting material 20 is nano diamond material.

[0086] In the above three embodiments, in the first light conversion unit 212 and the second light conversion unit 222 , the weight ratio of the thermal conductive material 20 can be 0.01-0.2, including end points.

[0087] In the above three embodiments, in the first primary color light emitting unit 210 and the second primary color light emitting unit 220 , the distance between the light conversion unit and the light emitting element in the direction perpendicular to the substrate 100 may be less than 5 μm, preferably in surface contact.

[0088] Optionally, in another embodiment of the present application, Figure 1 As shown, the light emitting unit 200 further includes:

[0089] A second primary color light emitting unit 220, the second primary color light emitting unit 220 comprises a second light emitting element 221 and a second light conversion unit 222 located on a side of the second light emitting element 221 away from the substrate 100, the second light conversion unit 222 is used to convert the light emitted by the second light emitting element 221 into a second primary color visible light;

[0090] Wherein, the second light conversion unit 222 includes a mixture of a second light conversion material 30 and a heat conductive material 20, and the second light conversion material 30 and the heat conductive material 20 adhere together by electrostatic attraction;

[0091] A third primary color light emitting unit 230, the third primary color light emitting unit 230 comprises a third light emitting element 231 and a third light conversion unit 232 located on a side of the third light emitting element 231 away from the substrate 100, the third light conversion unit 232 is used to convert the light emitted by the third light emitting element 231 into a third primary color visible light;

[0092] The third light conversion unit 232 includes a mixture of a third light conversion material 40 and a heat conductive material 20 , and the third light conversion material 40 and the heat conductive material 20 are adhered together by electrostatic attraction.

[0093] In this embodiment, the electrostatic attraction and adhesion between the second photoconversion material 30 and the thermal conductive material 20, and the electrostatic attraction and adhesion between the third photoconversion material 40 and the thermal conductive material 20 are the same as the electrostatic attraction and adhesion between the first photoconversion material 20 and the thermal conductive material 20, and will not be repeated here.

[0094] In this embodiment, the first primary color light-emitting unit 210, the second primary color light-emitting unit 220 and the third primary color light-emitting unit 230 are separated by a barrier 400, and the first primary color visible light, the second primary color visible light and the third primary color visible light can be red light, green light and blue light respectively. At this time, the first light-emitting element 211 and the second light-emitting element 221 can be blue light LEDs or ultraviolet light LEDs, and the third light-emitting element 231 is an ultraviolet light LED.

[0095] In this embodiment, the particle sizes of the first light conversion material 10, the second light conversion material 30 and the third light conversion material 40 can all be 1nm-10nm, including end values; the particle size of the thermal conductive material 20 does not exceed 300nm, preferably does not exceed 100nm.

[0096] Specifically, the first photoconversion material 10, the second photoconversion material 30 and the third photoconversion material 40 can all be quantum dot materials, and the quantum dot materials can be cadmium-based quantum dot materials (such as CdSe, CdS, etc.), cadmium-free quantum dot materials (such as InP, ZnO, etc.) or perovskite quantum dot materials (APbX3, where X = Cl, Br, I, etc.).

[0097] The heat conducting material 20 may be boron nitride quantum dot material, graphene quantum dot material, nano pure copper powder material, nano aluminum oxide material, carbon nano tube material or nano diamond material. Preferably, the heat conducting material 20 is nano diamond material.

[0098] In the present embodiment, in the first light conversion unit 212 , the second light conversion unit 222 , and the third light conversion unit 232 , the weight ratio of the thermal conductive material 20 may be 0.01-0.2, including end points.

[0099] It can be seen that in this embodiment, during the process of converting light by the light conversion materials in the first light conversion unit 212, the second light conversion unit 222 and the third light conversion unit 232, the heat generated by themselves can be quickly spread out through the adhered thermal conductive material and then transferred to the packaging shell, which strengthens the heat transfer path from the inside of the light conversion material to the packaging shell, so that the display panel can dissipate heat efficiently, and at the same time effectively alleviate the local heat accumulation of the light conversion material, thereby avoiding the problem of fluorescence quenching caused by the internal heat accumulation of the light conversion material, thereby affecting the light conversion efficiency.

[0100] Optionally, in another embodiment of the present application, Figure 6 As shown, the light emitting unit 200 further includes:

[0101] A second primary color light emitting unit 220, the second primary color light emitting unit 220 comprises a second light emitting element 221 and a second light conversion unit 222 located on a side of the second light emitting element 221 away from the substrate 100, the second light conversion unit 222 is used to convert the light emitted by the second light emitting element 221 into a second primary color visible light;

[0102] Wherein, the second light conversion unit 222 includes a mixture of a second light conversion material 30 and a heat conductive material 20, and the second light conversion material 30 and the heat conductive material 20 adhere together by electrostatic attraction;

[0103] The third primary color light emitting unit 230 includes a third light emitting element 231 and a light scattering unit 233 located on the side of the third light emitting element 231 away from the substrate 100. The light scattering unit 233 is used to change the emission angle of the light emitted by the third light emitting element 231 to improve the light utilization rate.

[0104] In this embodiment, the electrostatic attraction and adhesion between the second light conversion material 30 and the thermal conductive material 20 is the same as the electrostatic attraction and adhesion between the first light conversion material 20 and the thermal conductive material 20, which will not be described in detail herein.

[0105] In this embodiment, the first primary color light-emitting unit 210, the second primary color light-emitting unit 220 and the third primary color light-emitting unit 230 are separated by a barrier 400, and the first primary color visible light, the second primary color visible light and the third primary color visible light can be red light, green light and blue light respectively. At this time, the first light-emitting element 211 and the second light-emitting element 221 can be blue light LEDs or ultraviolet light LEDs, and the third light-emitting element is a blue light LED.

[0106] In this embodiment, the particle sizes of the first light conversion material 10 and the second light conversion material 30 can both be 1 nm-10 nm, including end values; the particle size of the thermal conductive material 20 does not exceed 300 nm, preferably does not exceed 100 nm.

[0107] Specifically, the first light conversion material 10 and the second light conversion material 30 can both be quantum dot materials, and the quantum dot materials can be cadmium-based quantum dot materials (such as CdSe, CdS, etc.), cadmium-free quantum dot materials (such as InP, ZnO, etc.) or perovskite quantum dot materials (APbX3, where X = Cl, Br, I, etc.).

[0108] The heat conductive material 20 may be boron nitride quantum dot material, graphene quantum dot material, nano pure copper powder material, nano aluminum oxide material, carbon nano tube material or nano diamond material. Preferably, the heat conductive material 20 is nano diamond material.

[0109] In the first light conversion unit 212 and the second light conversion unit 222 , the weight ratio of the thermal conductive material 20 may be 0.01-0.2, including end points.

[0110] It can be seen that in the present embodiment, during the process of light conversion by the light conversion materials in the first light conversion unit 212 and the second light conversion unit 222, the heat generated by the light conversion materials themselves can be quickly spread out through the adhered thermally conductive material and then transferred to the packaging shell, thereby strengthening the heat transfer path from the inside of the light conversion material to the packaging shell, so that the display panel can dissipate heat efficiently, and at the same time effectively alleviate the local heat accumulation of the light conversion material, thereby avoiding the problem of fluorescence quenching caused by the internal heat accumulation of the light conversion material, thereby affecting the light conversion efficiency.

[0111] Based on the above two embodiments, Figure 1 and Figure 6 As shown, the display panel also includes:

[0112] The color resist unit 300 is located on the side of the light-emitting unit 200 away from the substrate 100. The color resist unit 300 includes a first color resist unit 310, a second color resist unit 320 and a third color resist unit 330, wherein the first color resist unit 310 covers the first primary color light-emitting unit 210, the second color resist unit 320 covers the second primary color light-emitting unit 220, and the third color resist unit 330 covers the third primary color light-emitting unit 230.

[0113] Optionally, in one embodiment of the present application, Figure 1 and Figure 6 As shown, for a light-emitting unit provided with a light conversion unit, the light conversion unit in the light-emitting unit and the color resist unit corresponding to the light-emitting unit are aligned and bonded.

[0114] Optionally, in another embodiment of the present application, Figure 4 As shown, for a light-emitting unit provided with a light-conversion unit, in a direction perpendicular to the substrate 100, the distance between the light-conversion unit in the light-emitting unit and the light-emitting element in the light-emitting unit does not exceed 5 μm. Figure 5 As shown, for a light-emitting unit provided with a light conversion unit, in a direction perpendicular to the substrate 100, the light conversion unit in the light-emitting unit and the light-emitting element in the light-emitting unit are in contact, so that the thermal conductive material in the light conversion unit can simultaneously transfer the heat of the light conversion material and the heat of the light-emitting element.

[0115] Based on any of the above embodiments, the first primary color visible light is red light, the second primary color visible light is green light, and the third primary color visible light is blue light. The weight proportion of the thermal conductive material in the first light conversion unit 212 is greater than the weight proportion of the thermal conductive material in other light conversion units, so that the heat in the light conversion unit corresponding to the red light can be transferred to the packaging shell faster and more, thereby improving the stability of the light conversion unit corresponding to the red light.

[0116] Based on any of the above embodiments, Figure 1 , Figure 4-Figure 6 As shown, the display panel also includes:

[0117] The shielding layer 500 is located on a surface of the barrier 400 facing away from the substrate 100 , and adjacent color-resist units 300 are separated and arranged by the shielding layer 500 .

[0118] Continue as Figure 1 , Figure 4-Figure 6As shown, the display panel further includes: a protective glass or film 600 .

[0119] The present application also provides a method for preparing a display panel. Figure 7 As shown, the method includes:

[0120] S100: providing a substrate;

[0121] S200: forming a light-emitting unit on a substrate, the light-emitting unit comprising a first primary color light-emitting unit, the first primary color light-emitting unit comprising a first light-emitting element and a first light-converting unit located at a side of the first light-emitting element away from the substrate, the first light-converting unit being used to convert light emitted by the first light-emitting element into first primary color visible light;

[0122] The first light conversion unit includes a mixture of a first light conversion material and a heat conductive material, and the first light conversion material and the heat conductive material adhere together through electrostatic attraction.

[0123] In this embodiment, if Figure 8 As shown, the formation process of the first light conversion unit includes:

[0124] S10: processing the first photoconversion material so that the first photoconversion material carries a first type of charge;

[0125] S20: processing the thermal conductive material so that the thermal conductive material carries a second type of charge, and the second type of charge is opposite in electrical properties to the first type of charge;

[0126] S30: uniformly mixing the first photoconversion material carrying the first type of charge and the thermal conductive material carrying the second type of charge, so that the first photoconversion material and the thermal conductive material adhere to each other through electrostatic attraction of positive and negative charges;

[0127] S40: forming a first light conversion unit by using the first light conversion material and the heat conductive material that are evenly mixed.

[0128] For example, the first light conversion material carries positive charge and the thermal conductive material carries negative charge; or the first light conversion material carries negative charge and the thermal conductive material carries positive charge.

[0129] Optionally, the first light conversion material is a quantum dot material, and the process of processing the first light conversion material so that the first light conversion material carries the first type of charge includes:

[0130] Pre-coat the quantum dot material with a cationic surface ligand (containing Cd 2+ / Zn 2+ / Ag + The quantum dot material carries a positive charge.

[0131] Optionally, the thermal conductive material is a nano-diamond material, and the process of processing the thermal conductive material so that the thermal conductive material carries the second type of charge includes:

[0132] The nano-diamond material is treated in advance with an anionic surfactant (carboxylate, sulfonate, sulfate ester, phosphate ester, etc.) so that the nano-diamond material carries a negative charge.

[0133] It can be seen that in the present embodiment, in the first light conversion unit, the first light conversion material is used to convert the light emitted by the first light emitting element into first primary color visible light. In the process of the first light conversion material converting the light, its own heat can be quickly spread through the adhered thermal conductive material, and then transferred to the packaging shell, that is, the heat transfer path from the inside of the first light conversion material to the packaging shell is strengthened, so that the display panel can dissipate heat efficiently, and at the same time effectively alleviate the local heat accumulation of the first light conversion material, thereby avoiding the problem of the first light conversion material causing fluorescence quenching due to its internal heat accumulation and thus affecting the light conversion efficiency.

[0134] Among them, nanodiamond materials have ultra-high thermal conductivity (2000W·m -1 ·K -1 ), the material particle size is 5nm-100nm, the light transmittance is high, and the stability is also good. Therefore, after the nano diamond material is filled into the first light conversion unit as a heat conductive material, efficient heat transfer can be achieved, and the light conversion efficiency of the first light conversion material is almost not affected, that is, the optical performance is almost not affected. In addition, most of the nano diamond materials are single crystals, and their surface morphology is a relatively regular sphere or quasi-sphere, so that the nano diamond material has a large specific surface area, so that it has strong surface activity and can adsorb a large number of impurity atoms or groups, that is, it is easy for the nano diamond material to carry positive or negative charges, so as to adhere to the first light conversion material through electrostatic attraction.

[0135] In order to achieve efficient heat transfer while reducing the impact on optical performance, it is necessary to limit the weight ratio of the thermally conductive material in the first light conversion unit. Specifically, in one embodiment of the present application, in the first light conversion unit, the weight ratio of the thermally conductive material is 0.01-0.2, including endpoint values.

[0136] The present application also provides a display device 700, such as Fig. 9 As shown, the display panel 800 includes any of the above items. Since the display panel has been described in detail in the above embodiments, it will not be repeated here. The display device can be any electronic device with a display function, such as a touch screen, a mobile phone, a tablet computer, a laptop, an e-book or a TV.

[0137] In summary, in the display panel provided in the embodiment of the present application, the first light conversion unit includes a mixture of a first light conversion material and a thermally conductive material, and the first light conversion material and the thermally conductive material are adhered together by electrostatic attraction. Therefore, in the process of the first light conversion material converting light, its own heat can be quickly spread through the adhered thermally conductive material, and then transferred to the packaging shell, that is, the heat transfer path from the inside of the first light conversion material to the packaging shell is strengthened, so that the display panel can dissipate heat efficiently, and at the same time effectively alleviate the local heat accumulation of the first light conversion material, thereby avoiding the problem of fluorescence quenching caused by the internal heat accumulation of the first light conversion material and affecting the light conversion efficiency.

[0138] The various parts in this manual are described in a combination of parallel and progressive ways. Each part focuses on the differences from other parts, and the same or similar parts between the various parts can be referenced to each other.

[0139] With respect to the above description of the disclosed embodiments, the features described in the embodiments in this specification may be replaced or combined with each other, so that professionals in the field can implement or use the present application. Various modifications to these embodiments will be apparent to professionals in the field, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present application. Therefore, the present application will not be limited to the embodiments shown herein, but will conform to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A display panel, characterized in that: include: substrate; A light-emitting unit, the light-emitting unit is located on the substrate, the light-emitting unit includes a first primary color light-emitting unit, the first primary color light-emitting unit includes a first light-emitting element and a first light conversion unit located on a side of the first light-emitting element away from the substrate, the first light conversion unit is used to convert light emitted by the first light-emitting element into first primary color visible light; Wherein, the first light conversion unit comprises a mixture of a first light conversion material and a heat conductive material, and the first light conversion material and the heat conductive material adhere together by electrostatic attraction; The particle size of the first light conversion material is 1 nm-10 nm, including the endpoint value; the particle size of the thermal conductive material does not exceed 300 nm; In the first light conversion unit, the weight ratio of the thermal conductive material is 0.01-0.2, including endpoint values; the weight ratio of the first light conversion material is 0.8-0.99, including endpoint values.

2. The display panel according to claim 1, characterized in that: The first photoconversion material carries a first type of charge, and the thermal conductive material carries a second type of charge, and the first type of charge and the second type of charge are opposite in electrical properties.

3. The display panel according to claim 1, characterized in that: The heat-conducting material is boron nitride quantum dot material, graphene quantum dot material, nano pure copper powder material, nano aluminum oxide material, carbon nano tube material or nano diamond material.

4. The display panel according to claim 1, characterized in that: The first light conversion material is a quantum dot material, and the quantum dot material is a cadmium-based quantum dot material, a cadmium-free quantum dot material or a perovskite quantum dot material.

5. The display panel according to claim 1, characterized in that: In a direction perpendicular to the substrate, a distance between the first light emitting element and the first light conversion unit does not exceed 5 μm.

6. The display panel according to claim 1, characterized in that: The light-emitting unit further includes a second primary color light-emitting unit, the second primary color light-emitting unit including a second light-emitting element and a second light conversion unit located at a side of the second light-emitting element away from the substrate, the second light conversion unit being used to convert light emitted by the second light-emitting element into second primary color visible light; Wherein, the second light conversion unit comprises a mixture of a second light conversion material and a heat conductive material, and the second light conversion material and the heat conductive material adhere together by electrostatic attraction; The second light emitting element is a blue light LED, the first light emitting element is an ultraviolet light LED, and the weight proportion of the heat conductive material in the second light conversion unit is greater than the weight proportion of the heat conductive material in the first light conversion unit.

7. The display panel according to claim 1, characterized in that: The light-emitting unit further includes a second primary color light-emitting unit, the second primary color light-emitting unit including a second light-emitting element and a second light conversion unit located at a side of the second light-emitting element away from the substrate, the second light conversion unit being used to convert light emitted by the second light-emitting element into second primary color visible light; Wherein, the second light conversion unit comprises a mixture of a second light conversion material and a heat conductive material, and the second light conversion material and the heat conductive material adhere together by electrostatic attraction; The second primary color visible light is red light, the first primary color visible light is green light or blue light, and the weight proportion of the heat conductive material in the second light conversion unit is greater than the weight proportion of the heat conductive material in the first light conversion unit.

8. The display panel according to claim 1, characterized in that: The light-emitting unit further includes a second primary color light-emitting unit, the second primary color light-emitting unit including a second light-emitting element and a second light conversion unit located at a side of the second light-emitting element away from the substrate, the second light conversion unit being used to convert light emitted by the second light-emitting element into second primary color visible light; Wherein, the second light conversion unit comprises a mixture of a second light conversion material and a heat conductive material, and the second light conversion material and the heat conductive material adhere together by electrostatic attraction; The weight ratio of the heat-conducting material in the second light conversion unit is equal to the weight ratio of the heat-conducting material in the first light conversion unit.

9. A method for preparing a display panel, characterized in that: include: providing a substrate; A light-emitting unit is formed on the substrate, wherein the light-emitting unit includes a first primary color light-emitting unit, wherein the first primary color light-emitting unit includes a first light-emitting element and a first light-converting unit located at a side of the first light-emitting element away from the substrate, wherein the first light-converting unit is used to convert light emitted by the first light-emitting element into first primary color visible light; The formation process of the first light conversion unit includes: Processing a first photoconversion material so that the first photoconversion material carries a first type of charge; Processing the thermally conductive material so that the thermally conductive material carries a second type of charge, wherein the second type of charge is opposite in electrical property to the first type of charge; Mixing a first photoconversion material carrying a first type of charge and a thermally conductive material carrying a second type of charge evenly, so that the first photoconversion material and the thermally conductive material adhere to each other through electrostatic attraction of positive and negative charges; The first light conversion unit is formed by mixing a uniformly first light conversion material and a thermal conductive material; the particle size of the first light conversion material is 1nm-10nm, including endpoint values; the particle size of the thermal conductive material does not exceed 300nm; in the first light conversion unit, the weight proportion of the thermal conductive material is 0.01-0.2, including endpoint values; the weight proportion of the first light conversion material is 0.8-0.99, including endpoint values.

10. The method according to claim 9, characterized in that The first light conversion material is a quantum dot material, and the process of processing the first light conversion material so that the first light conversion material carries the first type of charge includes: The quantum dot material is pre-coated with surface ligands containing cations so that the quantum dot material carries a positive charge.

11. The method according to claim 10, characterized in that The thermal conductive material is a nano-diamond material, and the process of processing the thermal conductive material so that the thermal conductive material carries the second type of charge includes: The nano-diamond material is treated with an anionic surfactant in advance, so that the nano-diamond material carries a negative charge.

12. A display device, characterized in that: A display panel comprising any one of claims 1 to 8.

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