WO2021174753A1 - 发光复合膜层、背光模组及显示装置 - Google Patents

发光复合膜层、背光模组及显示装置 Download PDF

Info

Publication number
WO2021174753A1
WO2021174753A1 PCT/CN2020/104769 CN2020104769W WO2021174753A1 WO 2021174753 A1 WO2021174753 A1 WO 2021174753A1 CN 2020104769 W CN2020104769 W CN 2020104769W WO 2021174753 A1 WO2021174753 A1 WO 2021174753A1
Authority
WO
WIPO (PCT)
Prior art keywords
film layer
light
quantum dot
mass
diffusion
Prior art date
Application number
PCT/CN2020/104769
Other languages
English (en)
French (fr)
Inventor
周淼
宋自航
白雪
李吉
张鑫
Original Assignee
Tcl华星光电技术有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Tcl华星光电技术有限公司 filed Critical Tcl华星光电技术有限公司
Priority to US17/051,448 priority Critical patent/US20230161094A1/en
Publication of WO2021174753A1 publication Critical patent/WO2021174753A1/zh

Links

Classifications

    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133606—Direct backlight including a specially adapted diffusing, scattering or light controlling members
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G02B6/0056—Means for improving the coupling-out of light from the light guide for producing polarisation effects, e.g. by a surface with polarizing properties or by an additional polarizing elements
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/88—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing selenium, tellurium or unspecified chalcogen elements
    • C09K11/881—Chalcogenides
    • C09K11/883—Chalcogenides with zinc or cadmium
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/02—Use of particular materials as binders, particle coatings or suspension media therefor
    • C—CHEMISTRY; METALLURGY
    • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
    • C09K—MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE
    • C09K11/00—Luminescent, e.g. electroluminescent, chemiluminescent materials
    • C09K11/08—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials
    • C09K11/70—Luminescent, e.g. electroluminescent, chemiluminescent materials containing inorganic luminescent materials containing phosphorus
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/02—Diffusing elements; Afocal elements
    • G02B5/0205—Diffusing elements; Afocal elements characterised by the diffusing properties
    • G02B5/0236—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element
    • G02B5/0242—Diffusing elements; Afocal elements characterised by the diffusing properties the diffusion taking place within the volume of the element by means of dispersed particles
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B5/00—Optical elements other than lenses
    • G02B5/20—Filters
    • G02B5/206—Filters comprising particles embedded in a solid matrix
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0033—Means for improving the coupling-out of light from the light guide
    • G02B6/005—Means for improving the coupling-out of light from the light guide provided by one optical element, or plurality thereof, placed on the light output side of the light guide
    • G02B6/0051—Diffusing sheet or layer
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B6/00—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings
    • G02B6/0001—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems
    • G02B6/0011—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form
    • G02B6/0066—Light guides; Structural details of arrangements comprising light guides and other optical elements, e.g. couplings specially adapted for lighting devices or systems the light guides being planar or of plate-like form characterised by the light source being coupled to the light guide
    • G02B6/0073—Light emitting diode [LED]
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133602—Direct backlight
    • G02F1/133603—Direct backlight with LEDs
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B82—NANOTECHNOLOGY
    • B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
    • B82Y20/00—Nanooptics, e.g. quantum optics or photonic crystals
    • G—PHYSICS
    • G02—OPTICS
    • G02B—OPTICAL ELEMENTS, SYSTEMS OR APPARATUS
    • G02B2207/00—Coding scheme for general features or characteristics of optical elements and systems of subclass G02B, but not including elements and systems which would be classified in G02B6/00 and subgroups
    • G02B2207/101—Nanooptics
    • G—PHYSICS
    • G02—OPTICS
    • G02F—OPTICAL DEVICES OR ARRANGEMENTS FOR THE CONTROL OF LIGHT BY MODIFICATION OF THE OPTICAL PROPERTIES OF THE MEDIA OF THE ELEMENTS INVOLVED THEREIN; NON-LINEAR OPTICS; FREQUENCY-CHANGING OF LIGHT; OPTICAL LOGIC ELEMENTS; OPTICAL ANALOGUE/DIGITAL CONVERTERS
    • G02F1/00—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics
    • G02F1/01—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour 
    • G02F1/13—Devices or arrangements for the control of the intensity, colour, phase, polarisation or direction of light arriving from an independent light source, e.g. switching, gating or modulating; Non-linear optics for the control of the intensity, phase, polarisation or colour  based on liquid crystals, e.g. single liquid crystal display cells
    • G02F1/133—Constructional arrangements; Operation of liquid crystal cells; Circuit arrangements
    • G02F1/1333—Constructional arrangements; Manufacturing methods
    • G02F1/1335—Structural association of cells with optical devices, e.g. polarisers or reflectors
    • G02F1/1336—Illuminating devices
    • G02F1/133614—Illuminating devices using photoluminescence, e.g. phosphors illuminated by UV or blue light

Definitions

  • the present invention relates to the field of semiconductor technology, and more specifically, the present invention relates to a light-emitting composite film layer, a backlight module and a display device.
  • Quantum Dot is a semiconductor nanocrystalline material composed of dozens of atoms. Its three dimensions are all within 100 nanometers. It can generate light of a specific wavelength from an electronically excited state; different materials are composed Quantum dots of different sizes emit light at different wavelengths. Because the particle size of quantum dots is small—smaller than or close to the Bohr radius of exciton, the electron transport inside it is restricted, the electron limitation and coherence are enhanced, the quantum confinement effect is significant, and the continuous band structure becomes It has a discrete energy level structure with molecular characteristics, so quantum dots of different sizes, electrons and holes are quantum confined to different degrees, so after being excited by external energy, electrons will undergo transitions and emit fluorescence.
  • Quantum dots of different sizes Different colors of light will be emitted. The larger the size, the greater the peak position of the emitted light. At the same time, it is precisely because the energy level band gap of a quantum dot is greatly affected by its size, it is possible to excite light of different wavelengths by adjusting the size of the quantum dot or using quantum dots of different compositions.
  • quantum dots such as narrow half-peak width, high luminous purity, and adjustable emission wavelength with size
  • quantum dots have been widely used in the field of lighting and display.
  • the development of display technology has generally undergone continuous transformation from thick to thin, from black and white to color, from general definition to high definition, including the early cathode ray tube imaging technology and plasma display technology, as well as the mainstream organic light emitting diode display.
  • Technology and LCD technology The information that people get from the display device is no longer limited to simple numbers and images, but also requires the display device to have excellent color performance capabilities.
  • quantum dot technology to convert light emitted from various light sources (such as LCD backlights, light-emitting diodes (LED) and OLED light-emitting layers) has become the focus of display development.
  • quantum dots were formally applied to liquid crystal display (LCD), which can easily expand the color gamut of LCD and have the same or better "brightness” as organic EL (OLED).
  • OLED organic EL
  • QD OLED the blue emitting material is evaporated onto the high mobility thin film transistor (TFT) panel stack.
  • TFT thin film transistor
  • the QD material is used to convert blue light into RG to produce RGB sub-pixels; QD Compared with other OLED display technologies, OLED has similar or stronger performance in terms of high contrast, true black, fast response time, wide viewing angle, and wide color gamut.
  • Quantum dots are used in the field of display technology. They can use quantum dots to emit highly pure, high-quality red/green monochromatic light with concentrated energy spectrum, which surpasses the phosphor luminescence characteristics of traditional LED backlights. Display devices using this technology can be efficiently improved The color threshold of the display screen makes the colors more pure and vivid.
  • Quantum dot film is excited by blue LED backlight and mixed with blue light to form a white backlight is the most common application of quantum dot display technology.
  • the brightness viewing angle of blue LEDs is quite different from that of red and green, which ultimately leads to the use of QD-film in displays.
  • the phenomenon of large-scale role-biasing occurs.
  • the embodiment of the present invention provides a light-emitting composite film layer, a backlight module and a display device.
  • the light-emitting composite film layer includes a quantum dot film layer and a diffusion film layer covering at least one surface of the quantum dot film layer. Green light quantum dots, red light quantum dots and light diffusion particles are dispersed, and light diffusion particles are dispersed in the diffusion film layer.
  • the light diffusion effect of the light diffusion particles is used to diverge the blue light type to achieve the same brightness viewing angle as the red and green light of the quantum dots. The color shift even eliminates the color shift to solve the problem of large visual role shift when the existing quantum dot film (QD-film) is applied to the display.
  • a luminescent composite film layer in the first aspect of the present invention, includes a quantum dot film layer and a diffusion film layer.
  • the diffusion film layer is disposed on at least one surface of the quantum dot film layer.
  • Quantum dots and light diffusion particles are dispersed in the quantum dot film layer, and the quantum dots include green light quantum dots and red light quantum dots,
  • Light diffusion particles are dispersed in the diffusion film layer
  • the light diffusion particles are inorganic nano materials with a refractive index greater than 2.0.
  • the green light quantum dots include: one or more of ZnCdSe 2 , InP, Cd 2 SSe as a luminescent core, and one of CdS, ZnSe, ZnCdS 2 , ZnS, and ZnO as an inorganic protective shell layer Or more, and one or more of amines, organic acids, mercapto alcohols, and organic phosphorus as surface ligands;
  • the red light quantum dots include: one of CdSe, Cd 2 SeTe, and InAs as luminescent nuclei Or more, one or more of CdS, ZnSe, ZnCdS 2 , ZnS, ZnO as an inorganic protective shell, and one or more of amine, organic acid, mercapto alcohol, and organic phosphorus as a surface ligand kind.
  • the light diffusion particles are one or more of TiO 2 , ZnS, and ZrO 2.
  • the quantum dot film layer is obtained by adding quantum dots, light diffusion particles, a dispersant and a first diluent into the first dispersion medium and mixing uniformly, and the mass of the quantum dots accounts for the total quantum dot film layer.
  • the mass of the light diffusion particles in the quantum dot film layer accounts for 0.02 ⁇ 2.0wt% of the total mass of the quantum dot film layer
  • the mass of the first dispersion medium accounts for the quantum dot film 30 ⁇ 70wt% of the total mass of the layer
  • the mass of the dispersant accounts for 30 ⁇ 70wt% of the total mass of the quantum dot film
  • the mass of the first diluent accounts for 30 ⁇ 70 wt% of the total mass of the quantum dot film 70wt%.
  • the first dispersion medium is pressure-sensitive adhesive or resin
  • the dispersant is alkane, alkene, toluene, chloroform or propylene glycol methyl ether acetate
  • the first diluent is ethyl acetate.
  • the diffusion film layer is obtained by adding light diffusion particles and a second diluent to the second dispersion medium and mixing uniformly, and the mass of the light diffusion particles in the diffusion film layer accounts for 0.02 of the total mass of the diffusion film layer. ⁇ 2.0wt%, the mass of the second diluent accounts for 30 ⁇ 70wt% of the total mass of the diffusion film layer, and the mass of the second dispersion medium accounts for 30 ⁇ 70wt% of the total mass of the diffusion film layer.
  • the second dispersion medium is polyvinyl alcohol, polysulfone amide or resin, and the second diluent is water or alkane.
  • a water and oxygen barrier layer is also arranged between the quantum dot film layer and the diffusion film layer.
  • a backlight module which includes the light-emitting composite film layer described in the first aspect.
  • a display device which includes the backlight module described in the second aspect.
  • the luminescent composite film layer provided by the present invention includes a quantum dot film and a diffusion film layer covering at least one surface of the quantum dot film, in which green light quantum dots, red light quantum dots and light diffusion particles are dispersed
  • Light diffusion particles are dispersed in the diffusion film layer, and the light diffusion effect of the light diffusion particles is used to diverge the blue light type, achieving the same brightness viewing angle as the red and green light of the quantum dots, reducing color shift or even eliminating color shift.
  • FIG. 1 is a schematic structural diagram of an embodiment of a light-emitting composite film layer provided by the present invention.
  • FIG. 2 is a schematic structural diagram of another embodiment of the light-emitting composite film layer provided by the present invention.
  • FIG. 3 is a schematic structural diagram of a third embodiment of the light-emitting composite film layer provided by the present invention.
  • Figure 4a shows the red, green, and blue type of the quantum dot film in the prior art after being excited by the blue LED backlight.
  • Figure 4b shows the red, green, and blue light-emitting composite film layers of the present invention after being excited by the blue LED backlight.
  • FIG. 5 is a comparison diagram of the color point of the quantum dot film and the light-emitting composite film layer of the prior art after being excited by the blue LED backlight as a function of the viewing angle.
  • Fig. 6 is a comparison diagram of the color shift between the QD POL using the quantum dot film of the prior art, the QD POL using the light-emitting composite film layer of the present invention, and the LCD.
  • the word "exemplary” is used to mean “serving as an example, illustration, or illustration.” Any embodiment described as “exemplary” in the present invention is not necessarily construed as being more preferable or advantageous than other embodiments.
  • the present invention sets out details for the purpose of explanation. It should be understood that those of ordinary skill in the art can realize that the present invention can be implemented even without using these specific details. In other examples, well-known structures and processes will not be elaborated to avoid unnecessary details to obscure the description of the present invention. Therefore, the present invention is not intended to be limited to the illustrated embodiments, but should be consistent with the widest scope that conforms to the principles and features disclosed in the present invention.
  • first”, “second”, “third”, etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of indicated technical features. Therefore, the features defined with “first”, “second”, and “third” may explicitly or implicitly include one or more features.
  • “plurality” means two or more than two, unless otherwise specifically defined.
  • the present invention provides an optical multilayer composite film, which disperses a certain concentration of light diffusion particles in an organic polymer, coats them to form a film to form a diffusion film layer, and then covers the same dispersed light diffusion particles. On the dot film layer, it is used to improve the light type difference between the red and green light of the quantum dots and the blue backlight, and reduce or even eliminate the large visual deviation.
  • the embodiment of the present invention provides a light-emitting composite film layer.
  • the light-emitting composite film layer includes a quantum dot film layer 1 and a diffusion film layer 2.
  • the diffusion film layer 2 is disposed on On at least one surface of the quantum dot film layer 1, quantum dots and light diffusion particles are dispersed in the quantum dot film layer.
  • the quantum dots include green light quantum dots and red light quantum dots, and light diffusion particles are dispersed in the diffusion film layer, and the light diffusion particles are refractive Inorganic nanomaterials with a rate greater than 2.0.
  • FIG. 1 is a schematic structural diagram of an embodiment of the light-emitting composite film layer provided by the present invention, and the diffusion film layer 2 covers the upper surface of the quantum dot film layer 1.
  • FIG. 2 is a schematic structural view of another embodiment of the light-emitting composite film layer provided by the present invention.
  • the diffusion film layer 2 covers the lower surface of the quantum dot film layer 1.
  • Fig. 3 is a schematic structural diagram of a third embodiment of the light-emitting composite film provided by the present invention.
  • the upper and lower surfaces of the quantum dot film 1 are covered with a diffusion film layer, so that the diffusion particles can diverge the blue light type. The effect is better, and it can effectively reduce or even eliminate the role bias.
  • Quantum dots mainly have the following three characteristics: quantum size effect, surface effect and quantum tunneling effect.
  • Quantum size effect also known as quantum confinement effect, refers to the energy level at which the movement of electrons is constrained when the size of quantum dots is reduced to less than or close to the Bohr radius of excitons in semiconductor nanomaterials. Phenomena such as splitting and band gap enlargement.
  • Surface effect refers to the phenomenon that as the size of semiconductor nanoparticles decreases, the specific surface area (surface area/volume) increases significantly, and the ratio of the number of atoms on the surface of the nanoparticle to the total number of atoms increases sharply, which leads to the phenomenon that the properties of quantum dots change and the bond Increase, the surface activity and surface energy of the nanoparticles increase rapidly, which will increase the surface defects of the nanoparticles and increase their activity, which makes them easy to combine with other atoms; the generation of surface defects often leads to the quenching of the quantum dots' luminescence and destroys them.
  • Luminous efficiency when preparing quantum dots, surface modification is usually required on them, such as using wide band gap semiconductor materials to coat the particles, repairing surface dangling bonds, and eliminating non-radiative recombination centers; therefore, the present invention
  • the quantum dot adopts a structure of a light-emitting core, a conductive shell, and a ligand composed of a wide band gap organic compound on the outside of the shell to prevent the increase of unsaturated dangling bonds on the surface of the quantum dot, resulting in non-radiative recombination and reducing luminous efficiency.
  • Quantum tunneling effect It is assumed that a particle with a certain energy moves from the left side to the right side of the barrier.
  • quantum dots In addition to the above three characteristics, quantum dots also exhibit some other characteristics, such as Coulomb blocking effect, quantum interference effect, multi-body correlation and nonlinear effects, etc. The present invention is based on these characteristics of quantum dots, The component selection and preparation method are specially designed to ensure the excellent optical properties of the quantum dot film.
  • green light quantum dot can also be called “green quantum dot”, which emits green light when excited;
  • red light quantum dot can also be called “red quantum dot”, when excited Glows red light.
  • the shell and layer of quantum dots have a great influence on the luminescence properties of quantum dots (such as fluorescence peak position, fluorescence quantum yield, light stability, fluorescence half-height width, etc.). In the preparation process of the core/shell structured quantum dots, it is necessary to consider the degree of mismatch of lattice constants between the core material and the shell material.
  • the shell layer grows in epitaxial growth mode; when the lattice constant gap is relatively large, epitaxial growth is difficult to proceed, and the shell layer will lead to the formation of lattice dislocations and defects, destroying the shape and structure of the quantum dots , And lead to a decrease in fluorescence yield.
  • the quantum dots also often cause changes in the fluorescence peak position during the shell coating process, and the increase in the thickness of the shell will also broaden the size distribution of the quantum dots, which in turn causes the fluorescence half-height width of the quantum dots to broaden.
  • Green light quantum dots include: one or more of ZnCdSe 2 , InP, and Cd 2 SSe as the luminescent core, one or more of CdS, ZnSe, ZnCdS 2 , ZnS, and ZnO as the inorganic protective shell, and One or more of amines, organic acids, mercapto alcohols, and organic phosphorus as surface ligands; red light quantum dots include: one or more of CdSe, Cd 2 SeTe, and InAs as luminescent nuclei, as inorganic protection One or more of CdS, ZnSe, ZnCdS 2 , ZnS, and ZnO of the shell layer, and one or more of amines, organic acids, mercapto alcohols, and organic
  • the light diffusion particles are inorganic nanomaterials with a refractive index greater than 2.0.
  • the type of inorganic nanomaterials can be set according to actual needs, preferably one or more of TiO 2 , ZnS, and ZrO 2.
  • the above-mentioned preferred inorganic nanomaterials The material can transmit red and green light more effectively, and scatter blue light, eliminate the light type difference between blue backlight and quantum dot red and green light, and reduce or even eliminate the large visual role deviation.
  • the light diffusion particles may be spherical or irregularly shaped particles.
  • the particle size of the light diffusion particles can be set by those skilled in the art according to actual needs.
  • the particle size of the inorganic nanomaterial is less than 50 nm, more preferably less than 20 nm.
  • the light diffusion particles may also be micron-sized inorganic materials.
  • the quantum dot film layer is obtained by adding quantum dots, light diffusion particles, dispersant and first diluent into the first dispersion medium and mixing uniformly.
  • the mass of quantum dots accounts for 0.05 ⁇ 2.0wt% of the total mass of the quantum dot film, more preferably 1.0wt%.
  • the molar ratio of red quantum dots to green quantum dots is preferably 1:1. Those skilled in the art can also according to actual needs.
  • the mass of light diffusion particles in the quantum dot film layer accounts for 0.02 ⁇ 2.0wt% of the total mass of the quantum dot film layer, more preferably 1.0wt%
  • the mass of the first dispersion medium It accounts for 30-70wt% of the total mass of the quantum dot film
  • the mass of the dispersant accounts for 30-70wt% of the total mass of the quantum dot film
  • the mass of the first diluent accounts for 30-70wt% of the total mass of the quantum dot film.
  • the concentration of quantum dots ensures that the quantum dot film layer has excellent optical properties.
  • the quantum dot itself is an inorganic nanocrystalline material and needs to be uniformly dispersed to achieve uniform light emission.
  • the dispersion of quantum dots in the embodiment of the present invention is divided into two steps: the first step is to ultrasonically disperse the quantum dots in a dispersion medium. Ultrasound-cooling-continue to sonicate, the solution is clear and there is no precipitation or agglomeration when placed; in the second step, the dispersion medium and quantum dots are continuously mixed and sonicated until the dispersion is uniform and there is no agglomeration.
  • the preparation method of the quantum dot film layer includes: in the first step, the red quantum dots are ultrasonically dispersed in a dispersion medium, and ultrasonic-cooling-continuous ultrasonication, the solution is clear, and there is no precipitation or agglomeration when placed;
  • the green quantum dots are ultrasonically dispersed in the dispersion medium.
  • Ultrasound-cooling-continue ultrasonication the solution is clear, and there is no precipitation or agglomeration when placed.
  • the second step is to disperse the red quantum dots fully dispersed in the dispersion medium and the red quantum dots fully dispersed in the dispersion medium.
  • the green quantum dots, the dispersant and the first diluent are continuously mixed and sonicated until they are uniformly dispersed without agglomeration to obtain a quantum dot solution with a preset concentration, and the quantum dot solution is coated into a quantum dot film.
  • the preparation method of the quantum dot film layer includes: in the first step, the red quantum dots and the green quantum dots are simultaneously ultrasonically dispersed in a dispersion medium, and ultrasonic-cooling-continued ultrasonication, the solution is clear, and there is no precipitation when placed.
  • the red quantum dots and green quantum dots, dispersant and first diluent that are fully dispersed in the dispersion medium are mixed and sonicated until the dispersion is uniform without agglomeration, and a quantum dot solution with a preset concentration is obtained.
  • the quantum dot solution is coated on the substrate to form a quantum dot film.
  • the first dispersion medium is pressure-sensitive adhesive or resin.
  • the type of pressure-sensitive adhesive can be set by those skilled in the art according to actual needs. It is preferably a resin-based pressure-sensitive adhesive, and more preferably an acrylic pressure-sensitive adhesive. , Silicone pressure sensitive adhesive or polyurethane pressure sensitive adhesive.
  • the dispersant is alkane, alkene, toluene, chloroform or propylene glycol methyl ether acetate, and the dispersant promotes the red quantum dots and green quantum dots to be better dispersed in the dispersion medium.
  • the first diluent is ethyl acetate, which dilutes the quantum dot solution to a preset concentration.
  • the diffusion film layer is obtained by adding the light diffusion particles and the second diluent to the second dispersion medium and mixing uniformly. Specifically, the inorganic nano material with a refractive index greater than 2.0 and the second diluent are ultrasonically dispersed in the second dispersion medium, Continue to sonicate until the dispersion is uniform.
  • the mass of light diffusion particles in the diffusion film layer accounts for 0.02 ⁇ 2.0wt% of the total mass of the diffusion film layer
  • the mass of the second diluent accounts for 30 ⁇ 70wt% of the total mass of the diffusion film layer
  • the mass of the second dispersion medium accounts for the diffusion film layer. 30 ⁇ 70wt% of the total mass.
  • the concentration of light diffusion particles ensures effective divergence of blue light type, reduces the difference between blue light type and red light and green light, makes blue light type and QD excitation light red and green light unified, and eliminates color shift.
  • the second dispersion medium is polyvinyl alcohol, polysulfone amide or resin, and the second diluent is water or alkane.
  • the quantum dot film and the diffusion film layer are respectively prepared and then combined to obtain a light-emitting composite film layer.
  • a water and oxygen barrier layer is also provided between the quantum dot film layer and the diffusion film layer. Since quantum dots are easily quenched when encountering water and oxygen, the provision of a water-oxygen barrier layer can effectively overcome this defect of quantum dots and ensure the optical stability of the light-emitting composite film layer.
  • the material of the water and oxygen barrier layer can be set according to actual needs.
  • the material of the water and oxygen barrier layer is an inorganic oxide or an organic oxide. More preferably, the water and oxygen barrier layer is aluminum oxide, silicon oxide or silicon oxide/chromium composite, which has a good barrier effect on moisture and oxygen.
  • the light-emitting composite film layer of this embodiment can be used in QD POL (quantum dot polarizer) or QD EF (quantum dot enhancement film) backlight.
  • QD EF is an optical film added with two kinds of quantum dots. Dots can produce red and green light under blue light, and then mix with part of the blue light to get white light.
  • the quantum dot film in the prior art includes red quantum dots and green quantum dots.
  • the light pattern of the quantum dot film in the prior art is excited by a blue LED backlight, as shown in FIG. 4a.
  • the light pattern of the light-emitting composite film layer of the present invention is excited by a blue LED backlight, as shown in FIG. 4b.
  • R is the red light type
  • G is the green light type
  • B is the blue light type. Comparing Figures 4a and 4b, in Figure 4a, the blue light type is quite different from the red and green light types, while the blue light type in Figure 4b almost overlaps with the red and green light types.
  • the light-emitting composite film layer is used in display technology, which effectively improves the light type difference between the red and green light of the quantum dots and the blue backlight, and basically eliminates the color shift.
  • View Angle is the viewing angle
  • Intensity is the light intensity.
  • FIG 5 is a perspective of the color point over prior art quantum dot thin film layer and the light emitting compound is excited blue LED backlight (View Angle) change chart, improving the previous figure ⁇ x, ⁇ y improved to prior art quantum dots of color shift film changes with viewing angle curve, ⁇ x improve the light emission of the composite film of the present invention to improve ⁇ y color shift with viewing angle curve, will be apparent from the figure, the composite of the present invention, the light emitting After the ⁇ x of the film is improved, after the ⁇ y is improved, the two curves almost overlap, and the curve is flat, and the color point is almost unchanged with the increase of the viewing angle. Partial.
  • Figure 6 is a comparison diagram of QD POL using a quantum dot film of the prior art, QD POL using the luminescent composite film layer of the present invention, and LCD (Liquid Crystal Display) color shift.
  • ⁇ x is improved
  • ⁇ y Before the improvement , the color shift curve of QD POL using the quantum dot film of the prior art
  • ⁇ x LCD is an LCD color shift curve, apparent from the figure, ⁇ x improvement after The curve is closer to the ⁇ x LCD curve, and the improved ⁇ y curve is closer to the ⁇ y LCD curve, indicating that the optical performance of the QD POL machine using the luminescent composite film layer of the present invention is basically the same as that of the LCD.
  • mini LED+QLED QLED is the abbreviation of Quantum Dot Light Emitting Diodes, which is a self-luminous technology that does not require additional light sources
  • QD POL QD POL
  • LCD traditional LCD display technology
  • the embodiment of the present invention also provides a backlight module, the backlight module includes any one of the light-emitting composite film layers in the above-mentioned embodiments, the backlight module further includes an excitation device, the excitation device may be a blue LED, which is composed of blue The blue light emitted by the color LED excites the red quantum dots in the quantum dot film layer to emit red light, and at the same time excites the green quantum dots to emit green light, and the red light, green light and blue light are mixed to form a white backlight with no color shift.
  • the excitation device may be a blue LED, which is composed of blue The blue light emitted by the color LED excites the red quantum dots in the quantum dot film layer to emit red light, and at the same time excites the green quantum dots to emit green light, and the red light, green light and blue light are mixed to form a white backlight with no color shift.
  • An embodiment of the present invention also provides a display device, which includes the backlight module of the foregoing embodiment.
  • the light-emitting composite film layer provided by the present invention includes a quantum dot film and a diffusion film layer covering at least one surface of the quantum dot film.
  • the quantum dot film is dispersed with green light quantum dots, red light quantum dots and light diffusion particles, and the diffusion film layer is dispersed
  • the light diffusion particles use the light diffusion effect of the light diffusion particles to diverge the blue light, achieving the same brightness and viewing angle as the red and green light of the quantum dots, reducing color shift or even eliminating color shift. It solves the problem that the existing quantum dot film (QD-film) is applied to the display, which will cause a large visual role deviation.

Abstract

本发明公开了发光复合膜层、背光模组及显示装置，发光复合膜层包括量子点膜层和扩散膜层，扩散膜层设置在量子点膜层的至少一个表面上，量子点膜层内分散有量子点和光扩散粒子，量子点包括绿光和红光量子点，扩散膜层内分散有光扩散粒子。本发明将蓝光光型发散，使蓝光达到与红绿光相同的亮度视角，降低甚至消除色偏。

Description

发光复合膜层、背光模组及显示装置 技术领域
本发明涉及半导体技术领域，更为具体来说，本发明涉及一种发光复合膜层、背光模组及显示装置。
 背景技术
量子点（Quantum Dot，QD）是一种由数十个原子所构成的半导体纳米晶体材料，其三个维度的尺寸都在100纳米以内，能从电子激发态产生特定波长的发光；不同材料组成大小的量子点，放光波长不同。由于量子点的粒径较小—小于或者接近激子波尔半径，其内部的电子输运受到限制，电子的局限性和相干性增强，量子限域效应显著，且连续的能带结构变成具有分子特性的分立能级结构，所以不同尺寸的量子点，电子和空穴被量子限域的程度不一样，故在受到外来能量激发后，电子会发生跃迁，发射荧光，不同尺寸的量子点将发出不同颜色的光，尺寸越大，发出的光峰位也越大。同时，正是由于量子点的能级带隙受其尺寸影响较大，可以通过调控量子点的尺寸或使用不同成分的量子点来激发出不同波长的光。
正是由于量子点的半峰宽窄、发光纯度高、发射波长随尺寸可调等优异性能，量子点已经被广泛应用于照明和显示领域。显示技术的发展大致经历了从厚到薄、从黑白到彩色、从普清到高清的不断蜕变，其中包括了早期的阴极射线管成像技术和等离子体显示技术，以及如今主流的有机发光二极管显示技术和液晶显示技术。人们从显示设备到得到的讯息不再仅仅局限于简单的数字和图像，同时也需要显示设备具有极佳的色彩表现能力。使用量子点技术转换从各种光源发出的光（例如LCD背光、发光二极管（LED）和OLED发光层）已经成为显示器开发的焦点。2013年，量子点被正式应用于液晶显示屏（LCD），其可以轻松扩大LCD的色域，具有与有机EL（OLED）同等或更好的“鲜艳度”。 2018年初，三星开始开发QD OLED，在QD OLED中，蓝色发射材料被蒸发到高迁移率薄膜晶体管（TFT）面板叠层上，QD材料用于将蓝光转换为RG以产生RGB子像素；QD OLED与其他OLED显示技术相比，在高对比度、真实的黑色、快速响应时间、宽视角、宽色域等方面具有类似或更强的性能。量子点用于显示技术领域，可以借助量子点发出能谱集中、非常纯正的高质量红/绿单色光，超越传统LED背光的荧光粉发光特性，应用这种技术的显示设备可以高效地提升显示屏的色阈值、让色彩更加纯净鲜艳。
量子点薄膜（QD-film）被蓝色LED背光激发后与蓝光混合成白色背光是量子点显示技术最常见的应用。但是，由于量子点激发光红色和绿色（R/G）的亮度视角极大，蓝色LED的亮度视角与红色和绿色差异较大，最终导致量子点薄膜（QD-film）应用于显示中会发生大视角色偏的现象。
 技术问题
本发明实施例提供了一种发光复合膜层、背光模组及显示装置，该发光复合膜层包括量子点薄膜层和覆在量子点薄膜层至少一个表面上的扩散膜层，量子点薄膜内分散有绿光量子点、红光量子点和光扩散粒子，扩散膜层内分散有光扩散粒子，利用光扩散粒子的光扩散作用将蓝光光型发散，达到与量子点红绿光相同的亮度视角，降低色偏甚至消除色偏，以解决现有量子点薄膜（QD-film）应用于显示中会发生大视角色偏的问题。
 技术解决方案
为此，本发明实施例提供了如下技术方案：
本发明第一方面，提供了一种发光复合膜层，该发光复合膜层包括量子点膜层和扩散膜层，所述扩散膜层设置在所述量子点膜层的至少一个表面上，
所述量子点膜层内分散有量子点和光扩散粒子，所述量子点包括绿光量子点和红光量子点，
所述扩散膜层内分散有光扩散粒子，
所述光扩散粒子为折射率大于2.0的无机纳米材料。
进一步地，所述绿光量子点包括：作为发光核的ZnCdSe 2、InP、Cd 2SSe中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种；所述红光量子点包括：作为发光核的CdSe、Cd 2SeTe、InAs中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种。
进一步地，所述光扩散粒子为TiO 2、ZnS、ZrO 2中的一种或几种。
进一步地，所述量子点膜层通过将量子点、光扩散粒子、分散剂和第一稀释剂加入到第一分散介质中混合均匀得到，所述量子点的质量占所述量子点膜层总质量的0.05~2.0wt%，所述量子点膜层中光扩散粒子的质量占所述量子点膜层总质量的0.02~2.0wt%，所述第一分散介质的质量占所述量子点膜层总质量的30~70wt%，所述分散剂的质量占所述量子点膜层总质量的30~70wt%，所述第一稀释剂的质量占所述量子点膜层总质量的30~70wt%。
进一步地，所述第一分散介质为压敏胶或树脂，所述分散剂为烷烃、烯烃、甲苯、氯仿或丙二醇甲醚醋酸酯，所述第一稀释剂为乙酸乙酯。
进一步地，所述扩散膜层通过将光扩散粒子和第二稀释剂加入到第二分散介质中混合均匀得到，所述扩散膜层中光扩散粒子的质量占所述扩散膜层总质量的0.02~2.0wt%，所述第二稀释剂的质量占所述扩散膜层总质量的30~70wt%，所述第二分散介质的质量占所述扩散膜层总质量的30~70wt%。
进一步地，所述第二分散介质为聚乙烯醇、聚砜酰胺或树脂，所述第二稀释剂为水或烷烃。
进一步地，所述量子点膜层和所述扩散膜层之间还设置有水氧阻隔层。
本发明第二方面，提供了一种背光模组，该背光模组包括上述第一方面所述的发光复合膜层。
本发明第三方面，提供了一种显示装置，该显示装置包括上述第二方面所述的背光模组。
 有益效果
本发明的有益效果为：本发明提供的发光复合膜层包括量子点薄膜和覆在量子点薄膜至少一个表面上的扩散膜层，量子点薄膜内分散有绿光量子点、红光量子点和光扩散粒子，扩散膜层内分散有光扩散粒子，利用光扩散粒子的光扩散作用将蓝光光型发散，达到与量子点红绿光相同的亮度视角，降低色偏甚至消除色偏。
 附图说明
为了更清楚地说明本发明实施例中的技术方案，下面将对各个实施例描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域技术人员来讲，在不付出创造性劳动的前提下，还可以根据本发明下面具体描述中的这些附图获得其他的附图。
图1为本发明提供的发光复合膜层一个实施例的结构示意图。
图2为本发明提供的发光复合膜层另一个实施例的结构示意图。
图3为本发明提供的发光复合膜层第三个实施例的结构示意图。
图4a为现有技术的量子点薄膜被蓝色LED背光激发后的红、绿、蓝光型。
图4b为本发明的发光复合膜层被蓝色LED背光激发后的红、绿、蓝光型。
图5为现有技术的量子点薄膜与发光复合膜层被蓝色LED背光激发后的色点随视角变化对比图。
图6为采用现有技术的量子点薄膜的QD POL、采用本发明的发光复合膜层的QD POL与LCD色偏的对比图。
 本发明的实施方式
下面结合说明书附图对本发明提供的发光复合膜层、背光模组及显示装置的技术方案进行清楚、完整地描述，显然地，所描述的实施例仅是本发明一部分实施例，而不是全部的实施例。基于本发明中的实施例，本领域技术人员在没有作出创造性劳动前提下所获得的所有其他实施例，都属于本发明保护的范围。
在本发明中，“示例性”一词用来表示“用作例子、例证或说明”。本发明中被描述为“示例性”的任何实施例不一定被解释为比其它实施例更优选或更具优势。为了使本领域任何技术人员能够实现和使用本发明，给出了以下描述。在以下描述中，本发明为了解释的目的而列出了细节。应当明白的是，本领域普通技术人员可以认识到，即使在不使用这些特定细节的情况下也可以实现本发明。在其它的实例中，不会对公知的结构和过程进行详细阐述，以避免不必要的细节使本发明的描述变得晦涩。因此，本发明并非旨在限于所示的实施例，而是应与符合本发明所公开的原理和特征的最广范围相一致。
应理解本发明中所述的术语仅仅是为描述特别的实施方式，并非用于限制本发明。另外，对于本发明中的数值范围，应理解为具体公开了该范围的上限和下限以及它们之间的每个中间值。在任何陈述值或陈述范围内的中间值以及任何其他陈述值或在所述范围内的中间值之间的每个较小的范围也包括在本发明内。这些较小范围的上限和下限可独立地包括或排除在范围内。本发明中的“%”如无特殊说明，代表质量百分比。
除非另有说明，否则本文使用的所有技术和科学术语具有本发明所述领域的常规技术人员通常理解的相同含义。虽然本发明仅描述了优选的方法和材料，但是在本发明的实施或测试中也可以使用与本文所述相似或等同的任何方法和材料。本说明书中提到的所有文献通过引用并入，用以公开和描述与所述文献相关的方法和/或材料。在与任何并入的文献冲突时，以本说明书的内容为准。
此外，术语“第一”、“第二”、“第三”等仅用于描述目的，而不能将其理解为指示或暗示相对重要性或者隐含指明所指示的技术特征的数量。由此，限定有“第一”、“第二”、“第三”的特征可以明示或隐含地包括一个或者更多个特征。在本发明的描述中，“多个”的含义是两个或两个以上，除非另有明确具体的限定。
现有技术中，将量子点薄膜（QD-film）应用于显示领域时，其原理为：量子点被蓝色LED背光激发后的红光和绿光与蓝光混合成白色。但是，由于量子点激发光红色和绿色的亮度视角极大，蓝色LED的亮度视角与红光和绿光差异较大，会发生大视角色偏。针对此问题，本发明提供一种光学多层复合膜，其将一定浓度的光扩散粒子分散于有机聚合物中，涂布成膜形成扩散膜层，然后覆在同样分散有光扩散粒子的量子点膜层上，用于改善量子点红绿光与蓝色背光的光型差异，降低甚至消除大视角色偏。
具体的，请参阅图1、图2和图3，本发明实施例提供了一种发光复合膜层，该发光复合膜层包括量子点膜层1和扩散膜层2，扩散膜层2设置在量子点膜层1的至少一个表面上，量子点膜层内分散有量子点和光扩散粒子，量子点包括绿光量子点和红光量子点，扩散膜层内分散有光扩散粒子，光扩散粒子为折射率大于2.0的无机纳米材料。
如图1所示，图1是本发明提供的发光复合膜层一个实施例的结构示意图，扩散膜层2覆在量子点膜层1的上表面。
如图2所示，图2是本发明提供的发光复合膜层另一个实施例的结构示意图，扩散膜层2覆在量子点膜层1的下表面。
如图3所示，图3是本发明提供的发光复合膜层第三个实施例的结构示意图，量子点膜层1的上下表面均覆有扩散膜层，使扩散粒子对蓝光光型的发散效果更优，有效降低甚至消除大视角色偏。
量子点主要具有以下三个特性：量子尺寸效应、表面效应和量子遂穿效应。量子尺寸效应，也称作量子限域效应，指的是在半导体纳米材料中，当量子点的尺寸减少到小于或接近于激子波尔半径时，电子的运动因受到约束而出现的能级分裂和带隙增大等现象。表面效应指的是随着半导体纳米颗粒尺寸的减小，比表面积（表面积/体积）明显增加，纳米颗粒表面原子数与其总原子数之比急剧增加，从而导致量子点性质变化的现象和键的增加，纳米颗粒的表面活性和表面能迅速增加，这些都会使得纳米颗粒的表面缺陷增多且活性增强，极易与其他原子进行结合；表面缺陷的产生往往会导致量子点发光的淬灭，破坏其发光效率；因此，在制备量子点时，通常需要在其上进行表面修饰，如使用宽禁带半导体材料对颗粒进行壳层包覆，修复表面悬键，消除非辐射复合中心；因此，本发明的量子点采用发光核、导体壳、壳外包覆有宽带隙有机物构成的配体的结构，防止因为量子点表面不饱和悬挂键增多，导致非辐射复合，降低发光效率。量子遂穿效应：假定具有一定能量的粒子由势垒的左侧向右侧运动。在经典力学中，只有能量大于势垒的粒子能够越过势垒到达右侧，而能量小于势垒的粒子则被反射回去，不能透过壁垒。但在量子力学中，情况则不同，由于此时粒子表现出明显的波动性，因而不仅能量大于势垒的粒子能够通过，能量小于势垒的粒子也有一定的概率穿过势垒到达右侧。此时，将能量小于势垒高度的粒子仍然能够穿透势垒的现象称为量子遂穿效应。除上述的三种特性外，量子点还表现出一些其他的特性，如库伦阻塞效应，量子干涉效应，多体相关和非线性效应等等，本发明基于量子点的这些特性，对量子点的成分选择和制备方法进行了特殊的设计，保证量子点薄膜优异的光学性能。
在本发明中，术语“绿光量子点”也可称作“绿色量子点”，在被激发时发出绿色的光；术语“红光量子点”也可称作“红色量子点”，在被激发时发出红色的光。量子点的壳、层对量子点的发光性能（如荧光峰位、荧光量子产率、光稳定性、荧光半高宽等）有着较大的影响。在核/壳结构量子点的制备过程中，需要考虑核材料和壳材料之间的晶格常数的失配程度。如果晶格常数差距较小，则壳层以外延生长模式进行生长；当晶格常数差距比较大时，外延生长难以进行，壳层会导致晶格位错和缺陷形成，破坏量子点的形状结构，并导致荧光产率下降。量子点在壳层包覆过程中还往往会引起荧光峰位的变化，壳层厚度的增加也会使得量子点的尺寸分布变宽，进而导致量子点的荧光半高宽变宽。因此，本发明综合考虑以上因素，设定的绿光量子点和红光量子点的发光壳、无机保护壳层材料使最终制得的量子点薄膜具有优良的光学性能。绿光量子点包括：作为发光核的ZnCdSe 2、InP、Cd 2SSe中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种；红光量子点包括：作为发光核的CdSe、Cd 2SeTe、InAs中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种。
光扩散粒子为折射率大于2.0的无机纳米材料，其中，无机纳米材料的种类可以根据实际需求进行设定，优选为TiO 2、ZnS、ZrO 2中的一种或几种，上述优选的无机纳米材料能够更有效地透过红光和绿光，并对蓝光产生散射作用，消除蓝色背光与量子点红绿光的光型差异，降低甚至消除大视角色偏。光扩散粒子可以为球形或者不规则形状粒子。光扩散粒子的粒径本领域技术人员可以根据实际需求进行设定，优选的，无机纳米材料的粒径小于50nm，更优选小于20nm。光扩散粒子也可以为微米级无机材料。
量子点膜层通过将量子点、光扩散粒子、分散剂和第一稀释剂加入到第一分散介质中混合均匀得到。量子点的质量占量子点膜层总质量的0.05~2.0wt%，更优选为1.0wt%，红色量子点与绿色量子点的摩尔比优选为1:1，本领域技术人员也可以根据实际需要设定红色量子点与绿色量子点的摩尔比，量子点膜层中光扩散粒子的质量占量子点膜层总质量的0.02~2.0wt%，更优选为1.0wt%，第一分散介质的质量占量子点膜层总质量的30~70wt%，分散剂的质量占量子点膜层总质量的30~70wt%，第一稀释剂的质量占量子点膜层总质量的30~70wt%。量子点的浓度保证量子点膜层具有优良的光学性能。
量子点本身是一种无机的纳米晶体材料，需要保持分散均匀才可实现发光均匀，本发明实施例中量子点的分散分为两步：第一步，将量子点超声分散在分散介质中，超声-降温-继续超声，溶液呈澄清，放置无沉淀和团聚；第二步，将分散介质和量子点继续混合并超声，直至分散均匀无团聚。
在一些实施例中，量子点膜层的制备方法包括：第一步，将红色量子点超声分散在分散介质中，超声-降温-继续超声，溶液呈澄清，放置无沉淀和团聚；同时，将绿色量子点超声分散在分散介质中，超声-降温-继续超声，溶液呈澄清，放置无沉淀和团聚，第二步，将充分分散于分散介质中的红色量子点、充分分散于分散介质中的绿色量子点、分散剂和第一稀释剂继续混合并超声，直至分散均匀无团聚，得到预设浓度的量子点溶液，将量子点溶液涂布成量子点薄膜。
在另一些实施例中，量子点膜层的制备方法包括：第一步，将红色量子点和绿色量子点同时超声分散在分散介质中，超声-降温-继续超声，溶液呈澄清，放置无沉淀和团聚；第二步，将充分分散于分散介质中的红色量子点和绿色量子点、分散剂和第一稀释剂继续混合并超声，直至分散均匀无团聚，得到预设浓度的量子点溶液，将量子点溶液涂布在基材上形成量子点薄膜。
在本实施例中，第一分散介质为压敏胶或树脂，压敏胶的种类本领域技术人员可根据实际需求进行设定，优选为树脂型压敏胶，更优选为丙烯酸类压敏胶、有机硅类压敏胶或者聚氨酯类压敏胶。分散剂为烷烃、烯烃、甲苯、氯仿或丙二醇甲醚醋酸酯，分散剂促进红色量子点和绿色量子点更好地分散于分散介质中。第一稀释剂为乙酸乙酯，将量子点溶液稀释至预设浓度。
扩散膜层通过将光扩散粒子和第二稀释剂加入到第二分散介质中混合均匀得到，具体的，将折射率大于2.0的无机纳米材料和第二稀释剂超声分散于第二分散介质中，持续超声直至分散均匀。扩散膜层中光扩散粒子的质量占扩散膜层总质量的0.02~2.0wt%，第二稀释剂的质量占扩散膜层总质量的30~70wt%，第二分散介质的质量占扩散膜层总质量的30~70wt%。光扩散粒子的浓度保证对蓝光光型的有效发散，降低蓝光光型与红光和绿光的差异，使蓝光光型与QD激发光红光和绿光统一，消除色偏。
在本实施例中，第二分散介质为聚乙烯醇、聚砜酰胺或树脂，第二稀释剂为水或烷烃。
将分别制得量子点薄膜和扩散膜层后复合得到发光复合膜层。
在某些实施例中，量子点膜层和扩散膜层之间还设置有水氧阻隔层。由于量子点遇到水和氧容易发生猝灭，设置水氧阻隔层能有效克服量子点这一缺陷，保证发光复合膜层的光学稳定性。水氧阻隔层的材料可以根据实际需要进行设定，优选的，水氧阻隔层的材料为无机氧化物或者有机氧化物。更优选的，水氧阻隔层为氧化铝、氧化硅或氧化硅/铬复合物，对水气及氧气具有很好的阻隔作用。
本实施例的发光复合膜层可以用于QD POL（量子点偏光片），或QD EF（量子点增强膜）背光中，QD EF是一种添加了两种量子点的光学薄膜，两种量子点可以在蓝光照射下产生红光和绿光，与一部分透过的蓝光混合之后得到白光。
现有技术中的量子点薄膜包括红色量子点和绿色量子点，将现有技术的量子点薄膜用蓝色LED背光激发的光型图，如图4a所示。将本发明的发光复合膜层用蓝色LED背光激发的光型图，如图4b所示。图中R为红光光型，G为绿光光型，B为蓝光光型。对比图4a和4b，图4a中，蓝光光型与红光和绿光光型相差较大，而图4b中蓝光光型几乎与红光和绿光光型重合，由此可知，本发明的发光复合膜层应用于显示技术中，有效改善了量子点红绿光与蓝色背光的光型差异，基本消除了色偏。图中，View Angle为视角，Intensity为光强。
图5为现有技术的量子点薄膜与发光复合膜层被蓝色LED背光激发后的色点随视角（View Angle）变化对比图，图中△x 改善前，△y 改善前为现有技术的量子点薄膜的色偏随视角变化曲线，△x 改善后，△y 改善后为本发明的发光复合膜层的色偏随视角变化曲线，从图中可以明显看出，本发明的发光复合膜层的△x 改善后，△y 改善后两条曲线几乎重合，而且曲线平缓，随视角的增加色点几乎不变，说明本发明的发光复合膜有效发散了蓝光光型，几乎消除了色偏。
图6为采用现有技术的量子点薄膜的QD POL、采用本发明的发光复合膜层的QD POL与LCD（Liquid Crystal Display，液晶显示器）色偏的对比图，图中△x 改善前，△y 改善前为采用现有技术的量子点薄膜的QD POL的色偏曲线，
△x 改善后，△y 改善后为采用本发明的发光复合膜层的QD POL的色偏曲线，△x LCD，△y LCD为LCD色偏曲线，从图中明显看出，△x 改善后曲线更接近于△x LCD曲线，△y 改善后曲线更接近于△y LCD曲线，说明采用本发明的发光复合膜层的QD POL整机的光学性能与LCD基本相同。
将mini LED搭配现有技术的QLED（以下称为mini LED+QLED）（QLED是Quantum Dot Light Emitting Diodes的缩写，是不需要额外光源的自发光技术）、现有技术QD POL（以下称为QD POL技术改善前）和采用本发明发光复合膜层的QD POL（以下称为QD POL技术改善后）、传统LCD显示技术（以下称为LCD）整机色偏和亮度视角进行对比，如下表所示。
方案 视角亮度（1/2） 视角色偏（60°，△y）
Mini LED+QDEF 125° 0.11
QD POL技术改善前 130° 0.21
QD POL技术改善后 125° 0.05
LCD 55° 0.04
从表中可以看出，QD POL技术改善前（现有技术QD POL）、QD POL技术改善后（采用本发明发光复合膜层的QD POL）的光学规格与Mini LED+QDEF（mini LED搭配现有技术的QLED）、传统LCD显示技术对比：视角技术改善后的QD POL（采用本发明发光复合膜层的QD POL）整机保持了1/2亮度视角的优势，色偏与传统LCD接近，兼顾Mini LED技术与传统LCD显示技术的优点。
本发明实施例还提供了一种背光模组，该背光模组包括上述实施例中的任一种发光复合膜层，该背光模组还包括激励器件，激励器件可以为蓝色LED，由蓝色LED发出的蓝光激发量子点膜层中的红色量子点使其发出红光，并同时激发绿色量子点使其发出绿光，红光、绿光和蓝光混合成无色偏的白色背光。
本发明实施例还提供了一种显示装置，该显示装置包括上述实施例的背光模组。
以上所述仅为本发明的较佳实施例而已，并不用以限制本发明，凡在本发明实质内容上所作的任何修改、等同替换和简单改进等，均应包含在本发明的保护范围之内。
 工业实用性
本发明提供的发光复合膜层包括量子点薄膜和覆在量子点薄膜至少一个表面上的扩散膜层，量子点薄膜内分散有绿光量子点、红光量子点和光扩散粒子，扩散膜层内分散有光扩散粒子，利用光扩散粒子的光扩散作用将蓝光光型发散，达到与量子点红绿光相同的亮度视角，降低色偏甚至消除色偏。解决了现有量子点薄膜（QD-film）应用于显示中会发生大视角色偏的问题。

Claims (18)

  1. 发光复合膜层，其中，该发光复合膜层包括量子点膜层和扩散膜层，所述扩散膜层设置在所述量子点膜层的至少一个表面上，
    所述量子点膜层内分散有量子点和光扩散粒子，所述量子点包括绿光量子点和红光量子点，
    所述扩散膜层内分散有光扩散粒子，
    所述光扩散粒子为折射率大于2.0的无机纳米材料。
  2. 根据权利要求1所述的发光复合膜层，其中，所述绿光量子点包括：作为发光核的ZnCdSe 2、InP、Cd 2SSe中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种；所述红光量子点包括：作为发光核的CdSe、Cd 2SeTe、InAs中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种。
  3. 根据权利要求1所述的发光复合膜层，其中，所述光扩散粒子为TiO 2、ZnS、ZrO 2中的一种或几种。
  4. 根据权利要求1所述的发光复合膜层，其中，所述量子点膜层通过将量子点、光扩散粒子、分散剂和第一稀释剂加入到第一分散介质中混合均匀得到，所述量子点的质量占所述量子点膜层总质量的0.05~2.0wt%，所述量子点膜层中光扩散粒子的质量占所述量子点膜层总质量的0.02~2.0wt%，所述第一分散介质的质量占所述量子点膜层总质量的30~70wt%，所述分散剂的质量占所述量子点膜层总质量的30~70wt%，所述第一稀释剂的质量占所述量子点膜层总质量的30~70wt%。
  5. 根据权利要求4所述的发光复合膜层，其中，所述第一分散介质为压敏胶或树脂，所述分散剂为烷烃、烯烃、甲苯、氯仿或丙二醇甲醚醋酸酯，所述第一稀释剂为乙酸乙酯。
  6. 根据权利要求1所述的发光复合膜层，其中，所述扩散膜层通过将光扩散粒子和第二稀释剂加入到第二分散介质中混合均匀得到，所述扩散膜层中光扩散粒子的质量占所述扩散膜层总质量的0.02~2.0wt%，所述第二稀释剂的质量占所述扩散膜层总质量的30~70wt%，所述第二分散介质的质量占所述扩散膜层总质量的30~70wt%。
  7. 根据权利要求6所述的发光复合膜层，其中，所述第二分散介质为聚乙烯醇、聚砜酰胺或树脂，所述第二稀释剂为水或烷烃。
  8. 根据权利要求1所述的发光复合膜层，其中，所述量子点膜层和所述扩散膜层之间还设置有水氧阻隔层。
  9. 一种背光模组，其中，该背光模组包括权利要求1~8任一项所述的发光复合膜层。
  10. 一种显示装置，其中，该显示装置包括权利要求9所述的背光模组。
  11. 根据权利要求10所述的显示装置，其中，所述发光复合膜层包括量子点膜层和扩散膜层，所述扩散膜层设置在所述量子点膜层的至少一个表面上，
    所述量子点膜层内分散有量子点和光扩散粒子，所述量子点包括绿光量子点和红光量子点，
    所述扩散膜层内分散有光扩散粒子，
    所述光扩散粒子为折射率大于2.0的无机纳米材料。
  12. 根据权利要求11所述的显示装置，其中，所述绿光量子点包括：作为发光核的ZnCdSe 2、InP、Cd 2SSe中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种；所述红光量子点包括：作为发光核的CdSe、Cd 2SeTe、InAs中的一种或多种，作为无机保护壳层的CdS、ZnSe、ZnCdS 2、ZnS、ZnO中的一种或多种，以及作为表面配体的胺、有机酸、巯醇、有机磷中的一种或多种。
  13. 根据权利要求11所述的显示装置，其中，所述光扩散粒子为TiO 2、ZnS、ZrO 2中的一种或几种。
  14. 根据权利要求11所述的显示装置，其中，所述量子点膜层通过将量子点、光扩散粒子、分散剂和第一稀释剂加入到第一分散介质中混合均匀得到，所述量子点的质量占所述量子点膜层总质量的0.05~2.0wt%，所述量子点膜层中光扩散粒子的质量占所述量子点膜层总质量的0.02~2.0wt%，所述第一分散介质的质量占所述量子点膜层总质量的30~70wt%，所述分散剂的质量占所述量子点膜层总质量的30~70wt%，所述第一稀释剂的质量占所述量子点膜层总质量的30~70wt%。
  15. 根据权利要求14所述的显示装置，其中，所述第一分散介质为压敏胶或树脂，所述分散剂为烷烃、烯烃、甲苯、氯仿或丙二醇甲醚醋酸酯，所述第一稀释剂为乙酸乙酯。
  16. 根据权利要求11所述的显示装置，其中，所述扩散膜层通过将光扩散粒子和第二稀释剂加入到第二分散介质中混合均匀得到，所述扩散膜层中光扩散粒子的质量占所述扩散膜层总质量的0.02~2.0wt%，所述第二稀释剂的质量占所述扩散膜层总质量的30~70wt%，所述第二分散介质的质量占所述扩散膜层总质量的30~70wt%。
  17. 根据权利要求16所述的显示装置，其中，所述第二分散介质为聚乙烯醇、聚砜酰胺或树脂，所述第二稀释剂为水或烷烃。
  18. 根据权利要求11所述的显示装置，其中，所述量子点膜层和所述扩散膜层之间还设置有水氧阻隔层。
PCT/CN2020/104769 2020-03-06 2020-07-27 发光复合膜层、背光模组及显示装置 WO2021174753A1 (zh)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US17/051,448 US20230161094A1 (en) 2020-03-06 2020-07-27 Light-emitting composite film layer, backlight module, and display device

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202010150047.1 2020-03-06
CN202010150047.1A CN111458930A (zh) 2020-03-06 2020-03-06 发光复合膜层、背光模组及显示装置

Publications (1)

Publication Number Publication Date
WO2021174753A1 true WO2021174753A1 (zh) 2021-09-10

Family

ID=71684227

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2020/104769 WO2021174753A1 (zh) 2020-03-06 2020-07-27 发光复合膜层、背光模组及显示装置

Country Status (3)

Country Link
US (1) US20230161094A1 (zh)
CN (1) CN111458930A (zh)
WO (1) WO2021174753A1 (zh)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113437196A (zh) * 2021-06-24 2021-09-24 深圳市华皓伟业光电有限公司 一种大发散角smd封装成型方法
CN115991887A (zh) * 2021-10-19 2023-04-21 北京航空航天大学合肥创新研究院(北京航空航天大学合肥研究生院) 一种光转换薄膜及其制备方法和显示器件
CN114019721A (zh) * 2021-11-03 2022-02-08 惠州视维新技术有限公司 扩散板、背光模组及显示装置
CN114035378B (zh) * 2021-11-25 2023-06-27 深圳市华星光电半导体显示技术有限公司 显示装置
CN115167031A (zh) * 2022-06-15 2022-10-11 湖南鸿阳光电科技有限公司 液晶电视mini量子点背光模组

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103487857A (zh) * 2013-10-11 2014-01-01 张家港康得新光电材料有限公司 量子点薄膜及背光模组
JP2017019971A (ja) * 2015-07-14 2017-01-26 大日本印刷株式会社 量子ドットシート、バックライト及び液晶表示装置
CN108828836A (zh) * 2018-07-25 2018-11-16 惠州市华星光电技术有限公司 复合型偏光片和液晶显示器
CN110780488A (zh) * 2019-11-13 2020-02-11 Tcl华星光电技术有限公司 一种显示面板及显示装置
CN110794503A (zh) * 2019-11-25 2020-02-14 Tcl华星光电技术有限公司 量子点偏光片及其制作方法、显示装置
CN111103727A (zh) * 2018-10-25 2020-05-05 三星显示有限公司 显示装置
CN111435206A (zh) * 2019-01-14 2020-07-21 三星显示有限公司 显示设备

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20140027673A1 (en) * 2012-07-25 2014-01-30 Qd Vision, Inc. Method of making components including quantum dots, methods, and products
CN105759491B (zh) * 2016-05-06 2019-08-02 深圳市华星光电技术有限公司 液晶显示器、液晶显示模组及其液晶单元
CN106848079B (zh) * 2017-02-20 2019-08-27 纳晶科技股份有限公司 发光-电荷传输复合物、含有其的墨水、其制备方法及qled器件

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103487857A (zh) * 2013-10-11 2014-01-01 张家港康得新光电材料有限公司 量子点薄膜及背光模组
JP2017019971A (ja) * 2015-07-14 2017-01-26 大日本印刷株式会社 量子ドットシート、バックライト及び液晶表示装置
CN108828836A (zh) * 2018-07-25 2018-11-16 惠州市华星光电技术有限公司 复合型偏光片和液晶显示器
CN111103727A (zh) * 2018-10-25 2020-05-05 三星显示有限公司 显示装置
CN111435206A (zh) * 2019-01-14 2020-07-21 三星显示有限公司 显示设备
CN110780488A (zh) * 2019-11-13 2020-02-11 Tcl华星光电技术有限公司 一种显示面板及显示装置
CN110794503A (zh) * 2019-11-25 2020-02-14 Tcl华星光电技术有限公司 量子点偏光片及其制作方法、显示装置

Also Published As

Publication number Publication date
US20230161094A1 (en) 2023-05-25
CN111458930A (zh) 2020-07-28

Similar Documents

Publication Publication Date Title
WO2021174753A1 (zh) 发光复合膜层、背光模组及显示装置
US10345642B2 (en) Manufacturing method for color film substrate and LCD apparatus
US20180122613A1 (en) Quantum dot based lighting
CN106195923B (zh) 光转化膜以及具有所述光转化膜的背光单元和显示装置
Kim et al. Enhancement of optical efficiency in white OLED display using the patterned photoresist film dispersed with quantum dot nanocrystals
US10852584B2 (en) Method for quantum dot-polymer composite, quantum dot-polymer composite, light conversion film comprising same, backlight unit, and display device
US10175527B2 (en) Display panel and liquid crystal display
TWI442139B (zh) 液晶顯示裝置
US10263220B2 (en) Manufacturing method for QLED display
WO2017012133A1 (zh) 一种显示面板
US11397347B2 (en) Color filter substrate, manufacturing method thereof, and display device
US20200073169A1 (en) Optical member and display device including the same
CN105704869B (zh) 电致光致混合发光显示器件及其制作方法
JPWO2005115740A1 (ja) 面発光体
TW201703308A (zh) 電子元件中之半導體性粒子
US20170328539A1 (en) Color conversion film and plane light source using the same
WO2022011829A1 (zh) 一种量子点膜及其制备方法、显示装置
KR101114412B1 (ko) 나노 양자점이 분산된 광학시트 및 이를 포함하는 백라이트 유닛
JP2024037888A (ja) 表示装置
CN111416052A (zh) 显示面板和显示装置
US20220357618A1 (en) Backlight module and quantum dot display device
TW202018997A (zh) 發光元件及其製造方法
WO2020124865A1 (zh) 一种量子点偏光片
CN114106814B (zh) 量子点光致发光膜及其制备方法、显示装置
WO2004084323A1 (de) Organische leuchtdiode mit verbesserter lichteffizienz

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 20922895

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 20922895

Country of ref document: EP

Kind code of ref document: A1