CN210379051U - OLED light-emitting panel and display device - Google Patents

Abstract

The embodiment of the utility model discloses OLED luminescent panel and display device. The OLED light emitting panel includes: a substrate; the light-emitting unit comprises a first electrode, an organic functional layer and a second electrode, the first electrode is positioned on the substrate, the organic functional layer is positioned on one side, away from the substrate, of the first electrode, the second electrode is positioned on one side, away from the substrate, of the organic functional layer, the first electrode is a reflecting electrode, and the second electrode is a semitransparent electrode; the pre-packaging layer is positioned on one side, away from the substrate, of the light-emitting unit and wraps all the light-emitting units; the pre-packaging layer has water and oxygen barrier capability; and the transparent cover plate is positioned on one side of the pre-packaging layer, which is far away from the substrate, so that the packaging effect of the OLED light-emitting panel is stable, and the service life of the OLED light-emitting panel is prolonged.

Description

OLED light-emitting panel and display device

Technical Field

The embodiment of the utility model provides a relate to organic light emitting technology, especially relate to an OLED luminescent panel and display device.

Background

The flat display panel has many advantages of thin body, power saving, no radiation, etc., and is widely used. The conventional flat Display panel mainly includes a Liquid Crystal Display (LCD) panel and an Organic Light Emitting Display (OLED) panel. The OLED panel has excellent characteristics of self-luminescence, no need of a backlight source, high contrast, thin thickness, wide viewing angle, fast response speed, applicability to a flexible panel, wide temperature range, simple structure and process, etc., and is well recognized as a mainstream technology for next generation display, and is popular among various large display panel manufacturers.

For OLED light emitting panels, moisture and oxygen are the primary causes of failure of OLED light emitting panels. This is because, on the one hand, when the OLED light-emitting panel operates, electrons need to be injected from the cathode, which requires that the work function of the cathode is as low as possible, and the metal material (such as Al, Ag, or Ca) generally used as the cathode is more reactive than the active metal material, and is prone to oxidation reaction with the moisture and oxygen permeating into the metal material, so that an insulating layer is formed between the cathode and the organic functional layer, and the OLED light-emitting panel cannot emit light. On the other hand, the organic material in the organic functional layer can generate irreversible chemical reaction with water vapor and oxygen, so that the structures of organic molecules and polymers are damaged, and the luminous efficiency of the organic functional layer is reduced.

Currently, OLED light emitting panels usually adopt a thin film encapsulation method to block water and oxygen. Because the light-emitting unit and the thin film encapsulation layer need to be formed in different devices, during manufacturing, the light-emitting unit is formed in a vacuum evaporation chamber by evaporation, and then the light-emitting unit is transferred to other devices (such as a CVD device) from the vacuum evaporation device for encapsulation, so that the thin film encapsulation layer is formed. In the process of transferring it from the vacuum evaporation apparatus to another apparatus (e.g., a CVD apparatus), water and oxygen in the air adhere to the light emitting unit. During working, the existence of water vapor can induce electrochemical reaction between the anode and the cathode and electrolytic gas release of water, black spots are formed on the film packaging layer, the film packaging layer is bubbled, and the film packaging effect is lost. Undoubtedly, after the thin film encapsulation layer loses the encapsulation effect, along with the invasion of water oxygen, the OLED luminescent panel can lose efficacy, can't give out light normally, and the OLED luminescent panel is short-lived.

SUMMERY OF THE UTILITY MODEL

The utility model provides a OLED luminescent panel and display device to make the encapsulation effect of OLED luminescent panel stable, prolong OLED luminescent panel life-span.

In a first aspect, an embodiment of the present invention provides an OLED light-emitting panel, including:

a substrate;

the light-emitting unit comprises a first electrode, an organic functional layer and a second electrode, the first electrode is positioned on the substrate, the organic functional layer is positioned on one side, away from the substrate, of the first electrode, the second electrode is positioned on one side, away from the substrate, of the organic functional layer, the first electrode is a reflecting electrode, and the second electrode is a semitransparent electrode;

the pre-packaging layer is positioned on one side, away from the substrate, of the light-emitting unit and wraps all the light-emitting units; the pre-packaging layer has water and oxygen barrier capability;

and the transparent cover plate is positioned on one side of the pre-packaging layer, which is far away from the substrate.

Further, the material of the pre-encapsulation layer is at least one of the following materials:

NPB、C₆₀、CBP、Alq₃、MgF₂and ZnS.

Further, the cover plate is made of glass.

Further, the light extraction device also comprises a light extraction layer;

the light extraction layer is located between the pre-encapsulation layer and the light emitting unit.

Further, the sum of the thicknesses of the pre-encapsulation layer and the light extraction layer is greater than or equal to 200nm and less than or equal to 500 nm.

Further, the material of the light extraction layer is at least one of the following materials:

TPTE, TPPE, 2TNATA, NPB and TAPC.

Further, the adhesive also comprises an adhesive layer;

the adhesive layer is located between the cover plate and the substrate so as to bond the cover plate and the substrate into a whole, and the vertical projection of the adhesive layer on the substrate surrounds the vertical projection of all the light-emitting units on the substrate.

Further, the adhesive layer is made of epoxy resin.

In a second aspect, an embodiment of the present invention further provides a display device, including any one of the OLED light-emitting panel provided by the embodiments of the present invention.

The embodiment of the utility model provides a through setting up the pre-packaging layer that is located the luminescence unit and deviates from the side of substrate, all the luminescence units are wrapped up in the pre-packaging layer; the pre-packaging layer has water and oxygen barrier capability; lie in the prepackage layer deviates from the transparent cover plate of substrate one side has solved current OLED luminescent panel that adopts the film encapsulation and has lost efficacy easily because of water oxygen corrodes, can't normally give out light, the short-lived problem of OLED luminescent panel, realizes making the encapsulation effect of OLED luminescent panel stable, the effect of extension OLED luminescent panel life-span.

Drawings

Fig. 1 is a schematic structural diagram of an OLED light-emitting panel according to an embodiment of the present invention;

fig. 2 is a schematic structural diagram of another OLED light-emitting panel according to an embodiment of the present invention;

fig. 3 is a schematic structural diagram of a display device according to an embodiment of the present invention.

Detailed Description

The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.

Fig. 1 is a schematic structural diagram of an OLED light-emitting panel according to an embodiment of the present invention. Referring to fig. 1, the OLED light emitting panel includes: a substrate 10; at least one light-emitting unit 20 located on the substrate 10, wherein the light-emitting unit 20 includes a first electrode 21, an organic functional layer 22 and a second electrode 23, the first electrode 21 is located on the substrate 10, the organic functional layer 22 is located on a side of the first electrode 21 facing away from the substrate 10, the second electrode 23 is located on a side of the organic functional layer 22 facing away from the substrate 10, the first electrode 21 is a reflective electrode, and the second electrode 22 is a semitransparent electrode; the pre-packaging layer 30 is positioned on one side of the light-emitting units 20, which faces away from the substrate 10, and the pre-packaging layer 30 wraps all the light-emitting units 20; the pre-encapsulation layer 30 has water-oxygen barrier capability; a transparent cover plate 40 on the side of the pre-encapsulation layer 30 facing away from the substrate 10.

With continued reference to fig. 1, in operation of the OLED light-emitting panel, a bias voltage is applied between the first electrode 21 and the second electrode 23, and holes and electrons break through the interface energy barrier and migrate from both sides of the organic functional layer 22 to the organic functional layer 22, and the electrons and holes recombine to generate excitons on the organic functional layer 22, which are unstable and release energy that is transferred to molecules of the light-emitting material in the organic functional layer 22 to transition from the ground state to the excited state. The excited state is unstable, and excited molecules return to the ground state from the excited state, and radiation transitions to produce a light emission phenomenon. Alternatively, in the above scheme, the first electrode 21 may be set as an anode, and the second electrode 23 may be set as a cathode; the first electrode 21 may be a cathode and the second electrode 23 may be an anode.

The OLED light-emitting panel is a top-emission type light-emitting panel. Specifically, the light emitted from the organic functional layer 22 includes two sub-beams, namely a first sub-beam and a second sub-beam, wherein the first sub-beam is transmitted in a direction from the organic functional layer 22 to the second electrode 23. Since the second electrode 22 is a semi-transparent electrode, the cover plate is also a transparent cover plate, which allows light to pass through, so that the first part of the sub-beams can directly pass through the second electrode 23 and the cover plate. While the second part of the sub-beams is transmitted in a direction directed by the organic functional layer 22 towards the first electrode 21. Since the first electrode 21 is a reflective electrode, it has a high reflectance to light. The second part of the sub-beams will be reflected at the first electrode 21, forming reflected light, which will exit after passing through the organic functional layer 22, the second electrode 22 and the cover plate 40 in sequence.

According to the technical scheme, the pre-packaging layer 30 is arranged on one side, away from the substrate 10, of the light emitting unit 20, the pre-packaging layer 30 is arranged to wrap all the light emitting units 20, the pre-packaging layer 30 has water and oxygen blocking capacity, and the transparent cover plate 40 is arranged on the pre-packaging layer 30. During manufacturing, the light emitting unit 20 can be formed by using a vacuum evaporation device, and then the pre-encapsulation layer 30 can be formed by using the same vacuum evaporation device, so that the pre-encapsulation layer does not need to be transferred to other devices, and the risk of water and oxygen invasion in the transfer process is avoided. After the light emitting unit 20 and the pre-encapsulation layer 30 are completely fabricated, they are transferred from the vacuum evaporation apparatus to another apparatus for encapsulation (e.g., bonding the cover plate 40). Therefore, when the packaging material is transferred from a vacuum evaporation device to other devices for packaging, the pre-packaging layer 30 is formed, and the light-emitting unit 20 cannot be influenced by permeation of oxygen and water vapor in the air under the water and oxygen blocking effect of the pre-packaging layer 30, so that the failure probability of the OLED light-emitting panel can be reduced, and the service life of the OLED light-emitting panel can be prolonged.

On the basis, the transparent cover plate 40 is arranged in the OLED light-emitting panel, so that the sealing effect of the light-emitting unit 20 can be further improved, the failure probability of the OLED light-emitting panel is reduced, and the service life of the OLED light-emitting panel is prolonged.

Compared with the scheme of packaging by using the thin film packaging layer, the technical scheme provided by the application does not need to adopt an ion bombardment method to form the thin film packaging layer, so that the damage of the ion bombardment to the light-emitting unit can be reduced.

In addition, because the pre-packaging layer 30 can be formed in the same vacuum evaporation equipment with the light-emitting unit 20, the pre-packaging layer 30 can have a better packaging effect on the light-emitting unit 20, a drying sheet does not need to be mounted between the cover plate 40 and the light-emitting unit, the drying sheet can not absorb light emitted from the light-emitting unit, the bad phenomenon that the overall light transmittance of the OLED light-emitting panel is low can be caused, the cover plate 40 can be kept transparent, and the top-emitting OLED light-emitting panel can be guaranteed to be packaged by the cover plate. Meanwhile, because a drying sheet is not needed, the packaging method is simple, and the cost is reduced.

On the basis of the above technical solution, optionally, the material of the pre-encapsulation layer 30 is at least one of the following materials: NPB, C60, CBP, Alq3, MgF2 and ZnS. These materials have natural hydrophobicity that can meet the requirement that the pre-encapsulation layer 30 has water and oxygen barrier capability. These materials are translucent optical films, and have less absorption of light emitted from the light-emitting unit and less influence on the overall light-emitting effect of the OLED light-emitting panel. In addition, the materials have certain resistance capacity to thermal and mechanical movement, have good stability and can be suitable for different working environments.

In each of the above technical solutions, optionally, the material of the cover plate 40 is glass. The glass has high strain point, good thermal stability and stable chemical performance, and can adapt to various severe conditions (such as high temperature and the like) in the manufacturing process of the OLED light-emitting panel.

Fig. 2 is a schematic structural diagram of another OLED light-emitting panel according to an embodiment of the present invention. Referring to fig. 2, the OLED light-emitting panel further includes a light extraction layer 50; the light extraction layer 50 is positioned between the pre-encapsulation layer 30 and the light emitting unit 20. When light emitted from the organic functional layer 22 propagates outward, an spp (surface plasmon polariton) effect exists near the metal/dielectric interface. The spp effect causes the light emitting unit 20 to have a reduced light emitting efficiency. The light extraction layer 50 can suppress the spp effect. In addition, between the upper and lower metal electrodes (i.e., the first electrode 21 and the second electrode 23), the OLED also forms a fabry-perot optical resonant cavity. The light extraction layer 50 is adjusted to adjust the resonant cavity, thereby adjusting the light extraction efficiency and selecting the spectrum.

Optionally, the sum of the thicknesses of the pre-encapsulation layer and the light extraction layer is greater than or equal to 200nm, less than or equal to 500 nm. The arrangement can meet the requirement of the existing process precision on the premise that the light-emitting unit has a better packaging effect. Compared with the existing OLED light-emitting panel, the whole thickness of the OLED light-emitting panel cannot be increased, and the OLED light-emitting panel is favorably thinned.

Optionally, the material of the light extraction layer is at least one of the following materials: TPTE, TPPE, 2TNATA, NPB and TAPC. The materials have higher refractive index, which is beneficial to inhibiting the total reflection of light rays at the interface of the second electrode and the light extraction layer, thereby improving the transmittance of the light rays.

Optionally, with continued reference to fig. 2, the OLED lighting panel further includes an adhesive layer 60; the adhesive layer 60 is located between the cover plate 40 and the substrate 10 to bond the cover plate 40 and the substrate 10 together, and a vertical projection of the adhesive 60 layer on the substrate 10 surrounds vertical projections of all the light emitting units 20 on the substrate 10. This makes the cover plate 40 and the substrate 10 form a stable whole, which can give the light emitting unit 20 all-round protection, on one hand, the OLED light emitting panel has high water and oxygen blocking capability, and on the other hand, the light emitting unit 20 is prevented from being damaged by external force during use.

Optionally, the material of the adhesive layer 60 is epoxy resin. The epoxy resin has stable chemical property and good water and oxygen blocking capability, and can be suitable for different working environments.

The following is an exemplary method for fabricating an OLED light-emitting panel, but is not intended to limit the present application. The manufacturing method of the OLED light-emitting panel comprises the following steps:

firstly, providing the ultrathin glass, cleaning the ultrathin glass, and taking the cleaned ultrathin glass as a substrate.

Illustratively, the method for cleaning the ultrathin glass can comprise ① manually rubbing the surface of the glass by using a hundred-grade dust-free Bucadiken cleaning agent to remove organic matters on the surface, washing the surface of the glass by pure water to be hydrophilic, ② two times of Dicang and one time of pure water ultrasound for 20 minutes, and ③ alcohol is placed in an oven for drying after being washed by alcohol.

Second, a first electrode is formed on the substrate.

Optionally, a magnetron sputtering technique is used to sputter TiN/Al/TiN or other composite stack material as the first electrode.

And thirdly, evaporating a functional layer and a second electrode on the first electrode in a vacuum evaporation device.

And fourthly, evaporating and plating the light extraction layer and the pre-packaging layer of the OLED light-emitting panel on the second electrode in vacuum evaporation equipment.

Fifthly, taking the OLED light-emitting panel out of the vacuum evaporation equipment, and bonding a cover plate.

Fig. 3 is a schematic structural diagram of a display device according to an embodiment of the present invention. Referring to fig. 3, the display device 101 includes any one of the OLED light-emitting panels 201 provided in the embodiments of the present invention.

Since the display device 101 includes any one of the OLED light-emitting panels 201 provided by the embodiments of the present invention, it has the same or corresponding beneficial effects as the OLED light-emitting panel 201 included therein, and the description thereof is omitted here.

It should be noted that the foregoing is only a preferred embodiment of the present invention and the technical principles applied. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments described herein, but is capable of various obvious modifications, rearrangements, combinations and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail with reference to the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the scope of the present invention.

Claims (9)

1. An OLED light-emitting panel, comprising:

a substrate;

the light-emitting unit comprises a first electrode, an organic functional layer and a second electrode, the first electrode is positioned on the substrate, the organic functional layer is positioned on one side, away from the substrate, of the first electrode, the second electrode is positioned on one side, away from the substrate, of the organic functional layer, the first electrode is a reflecting electrode, and the second electrode is a semitransparent electrode;

the pre-packaging layer is positioned on one side, away from the substrate, of the light-emitting unit and wraps all the light-emitting units; the pre-packaging layer has water and oxygen barrier capability;

and the transparent cover plate is positioned on one side of the pre-packaging layer, which is far away from the substrate.

2. The OLED lighting panel of claim 1, wherein the material of the pre-encapsulation layer is at least one of:

NPB、C₆₀、CBP、Alq₃、MgF₂and ZnS.

3. The OLED lighting panel according to claim 1, characterized in that the material of the cover plate is glass.

4. The OLED light-emitting panel according to claim 1, further comprising a light-extraction layer;

the light extraction layer is located between the pre-encapsulation layer and the light emitting unit.

5. OLED light-emitting panel according to claim 4,

the sum of the thicknesses of the pre-encapsulation layer and the light extraction layer is greater than or equal to 200nm and less than or equal to 500 nm.

6. OLED light-emitting panel according to claim 4,

the material of the light extraction layer is at least one of the following materials:

TPTE, TPPE, 2TNATA, NPB and TAPC.

7. The OLED lighting panel according to claim 1, further comprising an adhesive layer;

the adhesive layer is located between the cover plate and the substrate so as to bond the cover plate and the substrate into a whole, and the vertical projection of the adhesive layer on the substrate surrounds the vertical projection of all the light-emitting units on the substrate.

8. OLED light-emitting panel according to claim 7,

the adhesive layer is made of epoxy resin.

9. A display device comprising the OLED light-emitting panel according to any one of claims 1 to 8.

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