CN113707832A

CN113707832A - Display device and manufacturing method thereof

Info

Publication number: CN113707832A
Application number: CN202010434716.8A
Authority: CN
Inventors: 孙明晓; 金南德; 乔明胜
Original assignee: Hisense Visual Technology Co Ltd
Current assignee: Hisense Visual Technology Co Ltd
Priority date: 2020-05-21
Filing date: 2020-05-21
Publication date: 2021-11-26

Abstract

The invention discloses a display device and a manufacturing method thereof.A luminescent layer material in an organic light-emitting diode device adopts an electrochemical coupling polymer which is an electrochemical coupling product prepared by adopting electrochemical oxidative dehydrogenation reaction. The luminescent layer is prepared by adopting an electrochemical method, so that an evaporator and an ink-jet printer which are high in cost are not needed, and complicated processes of firstly printing a luminescent material and then drying a solvent in an ink-jet printing process are not involved. The light-emitting layer is deposited on the anode in situ along with the electrochemical oxidative dehydrogenation reaction, and the deposited film has good compactness and uniformity, thereby being beneficial to improving the light-emitting performance of the OLED device. The electrochemical solution processing method utilizes a closed circuit, and the electrochemical oxidative dehydrogenation reaction can be carried out only on the surface of the anode as an electrode, so that the upper light-emitting layer can be deposited only on the surface of the anode, and the method has higher precision.

Description

Display device and manufacturing method thereof

Technical Field

The invention relates to the technical field of display, in particular to a display device and a manufacturing method thereof.

Background

The Organic Light Emitting Diode (OLED) display technology has the advantages of low power consumption, fast response speed, wide viewing angle, Light weight, flexibility, and the like, and is a display technology with great potential.

The conventional OLED manufacturing methods are mainly classified into evaporation methods and solution methods. The organic functional layer film prepared by the evaporation method has the characteristics of uniformity, flatness and clear interface. The OLED manufactured by the evaporation method has relatively excellent luminous performance, but the method has huge investment cost and low material utilization rate, so that the OLED product cost is very high.

The solution method, especially the OLED prepared by the ink-jet printing method has the characteristics of low investment cost, high material utilization rate, capability of preparing large-size and flexible devices and the like. The preparation of the flexible OLED panel with low cost and large area is facilitated. However, the ink jet printing method has a limited preparation viscosity and is difficult to prepare when the resolution of the panel is high.

Disclosure of Invention

In some embodiments of the present invention, the display device includes an organic light emitting diode device, and the material of the light emitting layer in the organic light emitting diode device uses an electrochemical coupling polymer, which is an electrochemical coupling product prepared by an electrochemical oxidative dehydrogenation reaction. The luminescent layer is prepared by adopting an electrochemical method, so that an evaporator and an ink-jet printer which are high in cost are not needed, and complicated processes of firstly printing a luminescent material and then drying a solvent in an ink-jet printing process are not involved. The light-emitting layer is deposited on the anode in situ along with the electrochemical oxidative dehydrogenation reaction, and the deposited film has good compactness and uniformity, thereby being beneficial to improving the light-emitting performance of the OLED device. The electrochemical solution processing method utilizes a closed circuit, and the electrochemical oxidative dehydrogenation reaction can be carried out only on the surface of the anode as an electrode, so that the upper light-emitting layer can be deposited only on the surface of the anode, and the method has higher precision.

In some embodiments of the present invention, the substituent of the electrochemical coupling polymer used in the light-emitting layer is substituted with an electron-withdrawing group and an electron-donating group, and the light-emitting layer can have a property of emitting light of different colors by substituting different electron-withdrawing groups and electron-donating groups.

In some embodiments of the present invention, the electron-withdrawing group in the electrochemically coupled polymer used in the light-emitting layer comprises: triazine groups, thioxanthene tetraoxide groups, oxadiazole groups, triphenylboron groups, naphthalimide groups, dicyanopyrazine groups and diboronathracene groups.

In some embodiments of the present invention, the electron donating groups in the electrochemically coupled polymers used in the light-emitting layer include: an m-benzenedicarbazole group, a dicarbazole group, a t-butylcarbazole group, a tricarbazole group, a dihydrophenazine group, an acridine group, a phenothiazine group, a phenoxazine group, and a diphenylamine group.

In some embodiments of the present invention, the light emitting layer comprises: a red light emitting layer, a green light emitting layer, and a blue light emitting layer.

In some embodiments of the present invention, the precursor material used for manufacturing the red light emitting layer is any one of the following materials:

correspondingly, the materials of the red light-emitting layer formed after the electrochemical oxidative dehydrogenation reaction are as follows:

in some embodiments of the present invention, the precursor material used for manufacturing the green light emitting layer is any one of the following materials:

correspondingly, the materials of the green light-emitting layer formed after the electrochemical oxidative dehydrogenation reaction are as follows:

in some embodiments of the present invention, the precursor material used for manufacturing the blue light emitting layer is any one of the following materials:

correspondingly, the materials of the blue light-emitting layer formed after the electrochemical oxidative dehydrogenation reaction are as follows:

in some embodiments of the present invention, the forming of the light emitting layer by an electrochemical method comprises:

placing a substrate base plate with an anode pattern in a luminescent material precursor solution and connecting an electrochemical workstation;

and controlling the electrochemical workstation to apply scanning voltage so as to enable the luminescent material precursor to generate oxidative dehydrogenation reaction on the surface of the anode and form an electrochemical coupling product on the surface of the anode.

In some embodiments of the present invention, a luminescent material precursor solution comprises: a solvent, a luminescent material precursor, and an electrolyte.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings needed to be used in the embodiments of the present invention will be briefly described below, and it is obvious that the drawings described below are only some embodiments of the present invention, and it is obvious for those skilled in the art that other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic cross-sectional structure diagram of a display device according to an embodiment of the present invention;

fig. 2 is a schematic cross-sectional view of an organic light emitting diode device according to an embodiment of the present invention;

fig. 3 is a second schematic cross-sectional view illustrating an organic light emitting diode device according to an embodiment of the invention;

fig. 4 is a flowchart of a method for manufacturing a display device according to an embodiment of the invention;

fig. 5 is a schematic diagram of an electrochemical reaction according to an embodiment of the present invention.

11-substrate, 12-organic light emitting diode device, 121-anode, 122-cathode, 123-light emitting layer, 124-hole injection layer, 125-hole transport layer, 126-electron transport layer, 21-electrochemical cell, 22-electrochemical workstation, 23-auxiliary electrode, 24-reference electrode.

Detailed Description

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, the present invention is further described with reference to the accompanying drawings and examples. Example embodiments may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of example embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and thus their repetitive description will be omitted. The words expressing the position and direction described in the present invention are illustrated in the accompanying drawings, but may be changed as required and still be within the scope of the present invention. The drawings of the present invention are for illustrative purposes only and do not represent true scale.

The OLED display device has the advantages of being light and thin, high in brightness, low in power consumption, fast in response, high in definition, good in flexibility, high in luminous efficiency and the like, and occupies an increasingly important position in the display field.

The OLED display device comprises an array substrate and an encapsulation cover plate.

The array substrate comprises a substrate and a Thin Film Transistor (TFT) driving circuit formed on the substrate, wherein the OLED device is formed on the TFT driving circuit and is electrically connected with the TFT circuit.

The packaging cover plate is arranged opposite to the array substrate and used for packaging the OLED device.

The OLED device includes an anode, a light emitting layer, and a cathode. The anode, the light-emitting layer and the cathode form a sandwich structure, after an electric field is generated between the anode and the cathode, electrons and holes can move to the light-emitting layer and are combined into excitons in the light-emitting layer, and the excitons excite light-emitting molecules to finally generate visible light.

At present, the most mature OLED preparation technology is a fine metal mask evaporation method, but the evaporation method has low material utilization rate and high equipment investment, so that the OLED panel manufacturing cost is high, and the further expansion of the OLED product market share is severely restricted. In addition, the evaporation technique is greatly limited in the field of preparing large-sized, high-resolution and flexible OLED displays.

The OLED panel prepared by the ink-jet printing technology has high material utilization rate and low production cost, and has huge application prospect particularly in the field of large-size and flexible OLED display. However, the uniformity of the OLED film prepared by the ink-jet printing method is poor, and no better solution is available at present. Meanwhile, the ink jet printing method has limited preparation precision and is difficult to prepare when the resolution of the panel is high.

In view of this, the embodiment of the present invention provides a method for preparing an OLED light-emitting layer by an electrochemical method, and compared with the conventional solution processing technology, the electrical preparation method has the advantages of good film forming property, high process precision, simplified process, low production cost, and the like, and can realize the manufacture of a high-resolution OLED display panel.

Fig. 1 is a schematic cross-sectional structure diagram of a display device according to an embodiment of the present invention.

Referring to fig. 1, a display device according to an embodiment of the present invention includes: a substrate 11 and an organic light emitting diode device 12 located on the substrate 11.

The substrate base plate 11 is generally located at the bottom of the display device for supporting and carrying all the elements in the display device. The shape of the substrate 11 is adapted to the shape of the display device, and the display devices currently applied to the fields of televisions, mobile terminals, and the like are all rectangular, so that the substrate 11 can also be rectangular; in addition, if the display device is applied to a special-shaped display device such as a smart watch, the substrate base plate can be correspondingly set to be in a shape of a circle or the like, which is not limited herein.

The display device in the embodiment of the invention can be a rigid display device or a flexible display device. When the substrate 11 of the rigid display device is made of a rigid material such as glass, the substrate 11 of the flexible display device is made of a flexible material such as Polyimide (PI).

Before the OLED is fabricated on the substrate 11, a driving circuit needs to be fabricated on the substrate, and a thin film transistor array may be formed on the substrate 11 by a thin film fabrication process to form the driving circuit. In the embodiment of the present invention, the OLED may be driven by a passive driving method or an active driving method.

The organic light emitting diode device 12 is located on the substrate base plate 11. The organic light emitting diode device 12 serves as a sub-pixel in the display device for image display.

Fig. 2 is a schematic cross-sectional view of an organic light emitting diode device according to an embodiment of the present invention.

Referring to fig. 2, the organic light emitting diode device 12 includes at least an anode 121, a cathode 122, and an emission layer 123.

The anode 121 is located above the substrate 11 and electrically connected to a driving circuit on the substrate 11.

The sub-pixels in the display panel are OLEDs, and the area of each anode electrode 121 defines a light emitting area of the OLED, i.e., an opening area of the sub-pixel. The size of the anode 121 may be determined according to the design and resolution of the display device, and is not limited herein. The anode may be generally rectangular in shape. The anode is made of Indium Tin Oxide (ITO) or the like.

The cathode 122 is located on a side of the anode 121 facing away from the substrate base plate 11, the cathode 122 is disposed opposite to the anode 121, and an electric field is generated between the cathode 122 and the anode 121 when an electric signal is applied.

The cathode 122 is typically disposed over the entire surface, and need not be individually disposed for each sub-pixel. The cathode 122 has a shape corresponding to the shape of the base substrate 11, and may be generally rectangular. The size of the cathode is determined by the footprint of all the OLEDs, with cathode 122 overlying all the OLEDs. The cathode is made of silver Ag or aluminum Al and the like.

The light-emitting layer 123 is located between the anode 121 and the cathode 122, and when an electric signal is applied to the anode 121 and the cathode 122 to form an electric field between the anode 121 and the cathode 122, electrons and holes move to the light-emitting layer 123 and combine into an excitation in the light-emitting layer 123, so that the light-emitting material is excited to emit light.

Fig. 3 is a second schematic cross-sectional view of an organic light emitting diode device according to an embodiment of the invention.

Referring to fig. 3, the organic light emitting diode device 12 according to the embodiment of the present invention further includes: a hole injection layer 124, a hole transport layer 125, and an electron transport layer 126.

A hole injection layer 124 is located on the surface of the anode 121 on the side facing away from the substrate base 11.

The hole injection layer 124 may be provided as a whole layer or may be provided only over the anode 121.

The entire layer of the hole injection layer 124 may provide holes for all OLED devices, and the process of disposing the hole injection layer 124 entirely is relatively simple.

However, only holes injected to the position of the anode 121 contribute to light emission of the OLED device, and thus the hole injection layer 124 may be formed only on the anode 121, which saves cost.

According to the embodiment of the invention, the hole injection layer 124 is arranged on the anode 121, so that the hole injection capability of the device can be improved, the stability of the device is increased, and the service life is prolonged.

The hole injection layer 124 is formed by a solution method using a polymer material. For example, poly (3, 4-ethylenedioxythiophene): poly (styrenesulfonic acid) (PEDOT: PSS) and other materials can be used for the hole injection layer 124.

Hole transport layer 125 is located on the surface of hole injection layer 124 on the side facing away from anode 121.

The hole transport layer 125 may be provided as a whole layer, or may be provided only at a position corresponding to the anode 121.

The hole transport layer 125 can improve hole transport ability, and facilitate transport of carriers to the light emitting layer 123. Meanwhile, the hole transport layer 125 also has the function of blocking electrons, so that the transport of carriers can be balanced, and the efficiency of the device can be improved.

The hole transport layer 125 is formed by a solution method using a polymer material. For example, Poly-bis (4-phenyl) (4-butylphenyl) amine (Poly-TPD) or the like can be used as the hole transport layer 125.

The electron transport layer 126 is located on the surface of the light-emitting layer 123 on the side facing away from the hole transport layer 125.

The electron transport layer 126 may be provided as a whole layer, or may be provided only at a position corresponding to the anode 121.

The electron transport layer 126 is used for injecting and transporting electrons, which is beneficial for transporting carriers to the light emitting layer 123, and the arrangement of the electron transport layer 126 can improve the efficiency of the device.

The electron transport layer 126 is made of an N-type semiconductor with a wide bandgap, and can ensure a strong carrier transport capability and a high carrier concentration. The material of the electron transport layer 126 may be 3,3'- [5' - [3- (3-pyridyl) phenyl ] [1,1':3',1 '-terphenyl ] -3, 3' -diyl ] bipyridine (TmPyPB) or 1,3, 5-tris (1-phenyl-1H-benzimidazol-2-yl) benzene (TPBi).

In the embodiment of the invention, the material of the light-emitting layer adopts an electrochemical coupling polymer, and the electrochemical coupling polymer is an electrochemical coupling product prepared by adopting an electrochemical oxidative dehydrogenation reaction.

Specifically, the anode 121 is patterned on the base substrate, and the base substrate on which the anode 121 is formed is placed in an electrochemical cell and connected to an electrochemical station. The anode 121 on the substrate base plate serves as one electrode in an electrochemical cell with a precursor solution of the light-emitting material. When the electrochemical workstation applies a voltage, the precursor of the luminescent material will undergo an oxidative dehydrogenation reaction on the surface of the anode 121 and form an electrochemical coupling product, the solubility of the formed electrochemical coupling product is low, and the electrochemical coupling product is deposited on the surface of the anode 121 based on the intermolecular interaction force to form a luminescent layer.

The electrochemical method provided by the embodiment of the invention is adopted to prepare the luminescent layer in the organic light-emitting diode device, so that an evaporator and an ink-jet printer which are high in cost are not needed, and complicated processes such as printing luminescent materials first and drying solvents in an ink-jet printing process are not involved.

The light-emitting layer 123 is deposited on the anode 121 in situ along with the electrochemical oxidative dehydrogenation reaction, and the deposited film has good compactness and uniformity, thereby being beneficial to improving the light-emitting performance of the OLED device. The electrochemical solution process uses a closed circuit, and an electrochemical oxidative dehydrogenation reaction occurs only on the surface of the anode 121 as an electrode, and thus, the upper light emitting layer 123 is deposited only on the surface of the anode 121. The high-selectivity deposition method avoids the problem of crosstalk caused by spraying printing ink to a place except the anode by the traditional ink-jet printing method, has higher precision, and can be applied to the manufacture of high-resolution and high-precision OLEDs based on the high selectivity.

In the embodiment of the present invention, the substituent of the electrochemical coupling polymer adopted in the light emitting layer 123 is substituted by an electron withdrawing group and an electron donating group, and by substituting different electron withdrawing groups and electron donating groups, the light emitting layer 123 can have a property of emitting light rays with different colors, and accordingly, the light emitting layers emitting light rays with different colors are sequentially formed on the surface of the anode 121, and thus, sub-pixels for image display can be formed.

The electron-withdrawing group in the electrochemical coupling polymer used in the light-emitting layer 123 includes, but is not limited to:

electron donating groups in the electrochemically coupled polymers employed in light-emitting layer 123 include, but are not limited to:

in order to prepare organic light emitting diode devices of different colors as sub-pixels, the light emitting layer 123 may include a red light emitting layer, a green light emitting layer, and a blue light emitting layer. Wherein the red light emitting layer can emit red light, and the organic light emitting diode device including the red light emitting layer serves as a red sub-pixel; the green light emitting layer may emit green light, and the organic light emitting diode device including the green light emitting layer serves as a green sub-pixel; the blue light emitting layer may emit blue light, and the organic light emitting diode device including the blue light emitting layer serves as a blue sub-pixel.

The electrochemical coupling polymer adopted by the red light-emitting layer is any one of the following polymers:

when red light emitting layer adopts

When the precursor used in the electrochemical cell in the preparation process is

The precursor material is subjected to a peroxide deoxidation reaction in an electrochemical cell solution to form an electrochemical coupling product, and the electrochemical coupling product is deposited on the surface of the anode to form a red light-emitting layer.

When red light emitting layer adopts

When red light emitting layer adopts

The electrochemical coupling polymer adopted by the green light-emitting layer is any one of the following polymers:

when the green luminescent layer adopts

The precursor material is subjected to a peroxide deoxidation reaction in an electrochemical cell solution to form an electrochemical coupling product, and the electrochemical coupling product is deposited on the surface of the anode to form a green light-emitting layer.

When the green luminescent layer adopts

When the green luminescent layer adopts

The precursor material is subjected to a peroxide deoxidation reaction in an electrochemical cell solution to form an electrochemical coupleAnd the combined product is deposited on the surface of the anode to form a green light-emitting layer.

The electrochemical coupling polymer adopted by the blue light-emitting layer is any one of the following polymers:

when a blue light-emitting layer is used

The precursor material is subjected to a peroxide deoxidation reaction in an electrochemical cell solution to form an electrochemical coupling product, and the electrochemical coupling product is deposited on the surface of the anode to form a blue light-emitting layer.

When a blue light-emitting layer is used

When a blue light-emitting layer is used

The following is a detailed description of a method for manufacturing a display device according to an embodiment of the present invention. Fig. 4 is a flowchart of a method for manufacturing a display device according to an embodiment of the invention.

Referring to fig. 4, a method for manufacturing a display device according to an embodiment of the present invention includes:

s10, forming a pattern of an anode on the substrate base plate;

s20, forming a light-emitting layer on the substrate with the anode pattern by adopting electrochemical oxidative dehydrogenation reaction;

and S30, forming a cathode on the light-emitting layer.

The light-emitting layer is deposited on the anode in situ along with the electrochemical oxidative dehydrogenation reaction, and the deposited film has good compactness and uniformity, thereby being beneficial to improving the light-emitting performance of the OLED device. The electrochemical solution process uses a closed circuit, and an electrochemical oxidative dehydrogenation reaction occurs only on the surface of an anode as an electrode, and thus, an upper light-emitting layer is deposited only on the surface of the anode. The high-selectivity deposition method avoids the problem of crosstalk caused by spraying printing ink to a place except the anode by the traditional ink-jet printing method, has higher precision, and can be applied to the manufacture of high-resolution and high-precision OLEDs based on the high selectivity.

Specifically, a pattern of an anode is formed on a substrate having a driving circuit formed thereon, the anode may be formed by an etching process, and the anode may be formed of Indium Tin Oxide (ITO).

After the pattern for forming the anode is prepared, the substrate with the anode needs to be washed and dried.

After cleaning the substrate base plate, a hole injection layer is formed on the anode by a solution method. The hole injection layer adopts poly (3, 4-ethylenedioxythiophene) and poly (styrene sulfonic acid) (PEDOT: PSS), and the thickness is 10nm-40 nm.

After the hole injection layer is formed, the substrate is vacuum-dried and baked, and then a hole transport layer is formed over the hole injection layer using a solution method. The hole transport layer adopts Poly-bis (4-phenyl) (4-butylphenyl) amine (Poly-TPD) with the thickness of 10nm-40 nm.

After the hole transport layer is formed, the substrate is vacuum-dried and baked.

Referring to fig. 5, in the preparation of the light emitting layer, the base substrate 11 on which the pattern of the anode is formed is placed in an electrochemical cell 21 containing a light emitting material precursor solution, and connected to an electrochemical workstation 22. Wherein, the anode on the substrate base plate 11 is used as a working electrode to be connected with the electrochemical workstation 22, the electrochemical cell 21 also comprises an auxiliary electrode 23 and a reference electrode 24, one end of the auxiliary electrode 23 is arranged in the solution of the electrochemical cell, and the other end is connected with the electrochemical workstation 22; a reference electrode 24 is placed in the solution of the cell at one end and connected to the electrochemical workstation 22 at the other end.

The reaction system is provided with two loops, wherein one loop consists of a working electrode (namely an anode on a substrate) and a reference electrode 24 and is used for testing the electrochemical reaction process of the working electrode; the other circuit consists of the working electrode and the auxiliary electrode 23 for transporting electrons to allow the electrochemical reaction to take place.

The luminescent material precursor solution contained in the electrochemical cell is electrolyte and consists of a solvent, a luminescent material precursor and electrolyte. Wherein, the solvent can adopt dichloromethane, chlorobenzene, dichlorobenzene and other organic solvents; the electrolyte can ensure that the electrolyte has enough conductivity; the concentration of the luminescent material precursor is typically less than 20 mg/ml.

And (2) placing the substrate base plate 11 with the anode pattern in the electrochemical cell, connecting corresponding electrodes, controlling the electrochemical workstation 22 to apply scanning voltage, and scanning by adopting cyclic voltammetry, wherein the scanning voltage range is 0-1.55V, so that the luminescent material precursor generates oxidative dehydrogenation reaction on the anode surface of the substrate base plate to form an electrochemical coupling product, the electrochemical coupling product has low solubility, and a luminescent layer is formed on the anode surface by deposition under the driving of intermolecular force.

When the light emitting layers with different colors are formed, the substrate base plate with the anode patterns is required to be placed in electrochemical cells with different electrolyte systems, and only voltage needs to be applied to the anodes for forming the corresponding light emitting layers, so that the corresponding light emitting layers can be formed on the surfaces of the anodes.

Specifically, when the red light-emitting layer is formed, the light-emitting material precursor in the electrochemical cell may employ any one of:

the luminescent material precursor is subjected to electrochemical oxidative dehydrogenation reaction in electrolyte, and an electrochemical coupling product is deposited on the surface of the anode to form a red luminescent layer. The luminescent material precursor correspondingly forms the following products (namely materials of a red luminescent layer) after electrochemical oxidative dehydrogenation reaction:

when forming the green light-emitting layer, the light-emitting material precursor in the electrochemical cell may employ any one of the following:

the luminescent material precursor is subjected to electrochemical oxidative dehydrogenation reaction in electrolyte, and an electrochemical coupling product is deposited on the surface of the anode to form a green luminescent layer. The luminescent material precursor correspondingly forms the following products (namely materials of a green luminescent layer) after electrochemical oxidative dehydrogenation reaction:

when forming the blue light emitting layer, the light emitting material precursor in the electrochemical cell may employ any one of:

the luminescent material precursor is subjected to electrochemical oxidative dehydrogenation reaction in electrolyte, and an electrochemical coupling product is deposited on the surface of the anode to form a blue luminescent layer. The luminescent material precursor correspondingly forms the following products (namely materials of a blue luminescent layer) after electrochemical oxidative dehydrogenation reaction:

after the light-emitting layer is formed, an electron transporting layer is deposited over the light-emitting layer, and the electron transporting layer is made of 3,3'- [5' - [3- (3-pyridyl) phenyl ] [1,1':3',1 '-terphenyl ] -3, 3' -diyl ] bipyridine (TmPyPB) or 1,3, 5-tris (1-phenyl-1H-benzimidazol-2-yl) benzene (TPBi).

After the electron transport layer is formed, a cathode is deposited over the electron transport layer, and the cathode may have a LiF/Al stacked structure.

After the organic light emitting diode device is manufactured, the display panel is packaged.

According to the first inventive concept, a display device includes an organic light emitting diode device in which a light emitting layer material employs an electrochemically coupled polymer that is an electrochemically coupled product prepared using an electrochemical oxidative dehydrogenation reaction. The luminescent layer is prepared by adopting an electrochemical method, so that an evaporator and an ink-jet printer which are high in cost are not needed, and complicated processes of firstly printing a luminescent material and then drying a solvent in an ink-jet printing process are not involved. The light-emitting layer is deposited on the anode in situ along with the electrochemical oxidative dehydrogenation reaction, and the deposited film has good compactness and uniformity, thereby being beneficial to improving the light-emitting performance of the OLED device. The electrochemical solution processing method utilizes a closed circuit, and the electrochemical oxidative dehydrogenation reaction can be carried out only on the surface of the anode as an electrode, so that the upper light-emitting layer can be deposited only on the surface of the anode, and the method has higher precision.

According to the second inventive concept, the substituent group of the electrochemical coupling polymer adopted by the light-emitting layer is substituted by the electron-withdrawing group and the electron-donating group, the light-emitting layer can have the property of emitting different color light rays by substituting different electron-withdrawing groups and electron-donating groups, and correspondingly, the light-emitting layers emitting different color light rays are sequentially formed on the surface of the anode, so that the sub-pixels for image display can be formed. Wherein, the electron-withdrawing group in the electrochemical coupling polymer adopted by the luminous layer comprises: triazine groups, thioxanthene tetraoxide groups, oxadiazole groups, triphenylboron groups, naphthalimide groups, dicyanopyrazine groups and diboronathracene groups. The electron donating groups in the electrochemically coupled polymers used in the light-emitting layer include: an m-benzenedicarbazole group, a dicarbazole group, a t-butylcarbazole group, a tricarbazole group, a dihydrophenazine group, an acridine group, a phenothiazine group, a phenoxazine group, and a diphenylamine group.

According to the third inventive concept, the forming of the light emitting layer using the electrochemical method specifically includes: placing a substrate base plate with an anode pattern in a luminescent material precursor solution and connecting an electrochemical workstation; and controlling the electrochemical workstation to apply scanning voltage so as to enable the luminescent material precursor to generate oxidative dehydrogenation reaction on the surface of the anode and form an electrochemical coupling product on the surface of the anode. Wherein the luminescent material precursor solution comprises: a solvent, a luminescent material precursor, and an electrolyte.

According to the fourth inventive concept, the precursor material used for manufacturing the red light emitting layer is any one of the following materials:

according to the fifth inventive concept, the precursor material used for manufacturing the green light emitting layer is any one of the following materials:

according to the sixth inventive concept, the precursor material used for manufacturing the blue light emitting layer is any one of the following materials:

while preferred embodiments of the present invention have been described, additional variations and modifications in those embodiments may occur to those skilled in the art once they learn of the basic inventive concepts. Therefore, it is intended that the appended claims be interpreted as including preferred embodiments and all such alterations and modifications as fall within the scope of the invention.

It will be apparent to those skilled in the art that various changes and modifications may be made in the present invention without departing from the spirit and scope of the invention. Thus, if such modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include such modifications and variations.

Claims

1. A display device, comprising:

a substrate base plate having a bearing function;

the organic light-emitting diode device is positioned on the substrate base plate and used for displaying images;

the organic light emitting diode device includes:

an anode located over the substrate base plate;

the cathode is positioned on one side of the anode, which is far away from the substrate base plate;

a light emitting layer between the anode and the cathode;

the material of the light-emitting layer adopts electrochemical coupling polymer.

2. The display device of claim 1, wherein the electrochemically coupled polymer is an electrochemically coupled product produced using an electrochemical oxidative dehydrogenation reaction.

3. The display device of claim 1, wherein the light-emitting layer employs an electrochemically coupled polymer having electron-withdrawing groups comprising: triazine groups, thioxanthene tetraoxide groups, oxadiazole groups, triphenylboron groups, naphthalimide groups, dicyanopyrazine groups and diboronathracene groups.

4. The display device of claim 1, wherein the light-emitting layer employs an electrochemically coupled polymer in which the electron-donating group comprises: an m-benzenedicarbazole group, a dicarbazole group, a t-butylcarbazole group, a tricarbazole group, a dihydrophenazine group, an acridine group, a phenothiazine group, a phenoxazine group, and a diphenylamine group.

5. The display device according to claim 1, wherein the light-emitting layer comprises: a red light emitting layer, a green light emitting layer, and a blue light emitting layer.

6. The display device according to claim 5, wherein the red light emitting layer uses an electrochemically coupled polymer which is any one of:

7. the display device according to any one of claims 1 to 6, wherein the organic light emitting diode device further comprises:

a hole injection layer between the anode and the light emitting layer;

and the electron transport layer is positioned between the cathode and the light-emitting layer.

8. A method for manufacturing a display device, comprising:

forming a pattern of an anode on a substrate;

forming a light-emitting layer on a substrate with an anode pattern by adopting an electrochemical oxidative dehydrogenation reaction;

and forming a cathode on the light emitting layer.

9. The method of claim 8, wherein the electrochemically forming the light-emitting layer comprises:

and controlling the electrochemical workstation to apply a scanning voltage so that the luminescent material precursor generates oxidative dehydrogenation reaction on the surface of the anode to form an electrochemical coupling product on the surface of the anode.

10. The fabrication method of claim 9, wherein the luminescent material precursor solution comprises: a solvent, a luminescent material precursor, and an electrolyte;

the luminescent material precursor includes: