CN108878689B - A substrate and its preparation method, and a display device - Google Patents

Abstract

The embodiment of the invention provides a substrate, a preparation method thereof and a display device, relates to the technical field of display, and can solve the problem that the thickness of a light-emitting function layer formed in an opening area of an existing pixel definition layer is not uniform. The preparation method of the substrate comprises the following steps: forming a pixel defining layer film on a substrate; the material of the pixel defining layer film comprises photoresist, and a hydrophilic material, an elastic material and auxiliary particles which are doped in the photoresist; the auxiliary particles are used for releasing gas when being decomposed, and the elastic material is used for expanding the pixel defining layer film when the auxiliary particles release the gas; the molecular weight of the hydrophilic material, the photoresist and the elastic material is larger than that of the auxiliary particles; heating the pixel defining layer film to enable the auxiliary particles to move in a direction far away from the substrate; and processing the pixel defining layer film to form a pixel defining layer, and decomposing the auxiliary particles to release gas. For the preparation of the pixel defining layer.

Description

A substrate and its preparation method, and a display device

technical field

The present invention relates to the field of display technology, and in particular, to a substrate, a preparation method thereof, and a display device.

Background technique

Organic Electro-luminescent Display (OLED) has many advantages such as self-luminescence, high luminous efficiency, low operating voltage, lightness, flexibility, and simple manufacturing process. It has been widely used in display, lighting and other fields. application.

At present, there are two ways to form the light-emitting layer in OLED devices, one is the evaporation process, which is suitable for the production of small-sized OLED devices; the other is the solution process, which includes spin coating, inkjet printing or screen printing, etc. The method of film formation using the solution process is widely used in the production process of OLED devices due to its advantages of low cost, high productivity, and suitability for the production of large-sized OLED devices.

The existing pixel definition layer (Pixel Definition Layer, PDL for short) is composed of retaining walls. As shown in FIG. 1 , the width of the retaining walls gradually decreases along the direction from close to the base substrate 10 to the direction away from the base substrate 10 , that is, the pixel The cross section of the defining layer 20 perpendicular to the base substrate 10 is a normal trapezoid. Since the material forming the pixel defining layer 20 has affinity (the material of the pixel defining layer 20 includes photoresist and an affinity material), when a solution process such as ink-jet printing is performed in the opening area of the pixel defining layer 20 , referred to as IJP) to form the luminescent functional layer (Electroluminescent, referred to as EL) 30, and when the ink includes a hydrophilic material, the ink will climb along the sidewall of the pixel defining layer 20 during the drying process, so that the pixel defining layer 20 is formed. The light-emitting functional layer 30 formed in the opening area is thin in the middle and thick at the edges, that is, the thickness of the light-emitting functional layer 30 is uneven, which affects the light-emitting effect of the OLED device, resulting in poor brightness uniformity of the OLED device, which in turn affects the life of the OLED device.

SUMMARY OF THE INVENTION

Embodiments of the present invention provide a substrate, a method for manufacturing the same, and a display device, which can solve the problem of uneven thickness of the light-emitting functional layer formed in the opening area of the existing pixel definition layer.

To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

In a first aspect, a method for preparing a substrate is provided, comprising: forming a pixel definition layer film on a base substrate; wherein, the material of the pixel definition layer film includes photoresist and a material doped in the photoresist. a hydrophilic material, an elastic material and auxiliary particles; the auxiliary particles are used to release gas when decomposing, and the elastic material is used to expand the pixel definition layer film when the auxiliary particles release gas; the affinity The molecular weights of the elastic material, the photoresist and the elastic material are all larger than the molecular weight of the auxiliary particles; heating the pixel definition layer film to make the auxiliary particles move in a direction away from the base substrate; The pixel definition layer film is processed to form a pixel definition layer, and the auxiliary particles are decomposed to release gas.

Preferably, the pixel-defining layer film is processed to form a pixel-defining layer, and the auxiliary particles are decomposed to release gas, which specifically includes: exposing and developing the pixel-defining layer film to form a pixel-defining layer; The auxiliary particles in the pixel-defining layer are decomposed, so that the auxiliary particles are decomposed to release gas; or, the pixel-defining layer film is exposed and developed to form a pixel-defining layer, and the auxiliary particles are decomposed Gas is released.

Further preferably, decomposing the auxiliary particles in the pixel-defining layer to decompose the auxiliary particles to release gas, specifically comprising: heating the auxiliary particles in the pixel-defining layer or The light treatment decomposes the auxiliary particles to release gas.

Preferably, the pixel-defining layer includes an opening area and a pixel-defining area for defining the opening area; after the pixel-defining layer film is processed to form a pixel-defining layer, the preparation method further includes: in the pixel The opening area of the defining layer forms a light-emitting functional layer.

Further preferably, forming the light-emitting functional layer in the opening area of the pixel defining layer includes: printing ink containing the material of the light-emitting functional layer in the opening area of the pixel defining layer by using an inkjet printing method.

Preferably, the auxiliary particles are azo compound particles.

Preferably, the elastic material includes at least one of thermoplastic polyester elastomer, thermoplastic polyurethane elastomer or thermoplastic EPDM dynamic vulcanization elastomer.

Preferably, the affinity material includes at least one of polyimide, bisphenol A polycarbonate, a polymer containing an alkyl group in the main chain, and a polymer containing a cyclic rigid structure in the main chain.

In a second aspect, a substrate is provided, and the substrate is prepared and formed by the above-mentioned preparation method.

In a third aspect, a display device is provided, including the above-mentioned substrate.

Embodiments of the present invention provide a substrate, a method for preparing the same, and a display device. When a pixel defining layer is prepared on the base substrate, since the material of the pixel defining layer film includes not only photoresist and affinity material, but also auxiliary particles and elastic material, after heating the pixel definition layer film, the auxiliary particles in the pixel definition layer film will move away from the base substrate, so that the distribution density of auxiliary particles in the direction from close to the base substrate to away from the base substrate Gradually increase, so when the pixel definition layer film is processed and the auxiliary particles are released gas, the distribution density of auxiliary particles gradually increases in the direction from approaching the base substrate to the direction away from the base In the direction away from the base substrate, the amount of gas released by the decomposition of the auxiliary particles gradually increases, so the expansion degree of the pixel defining layer gradually increases. In the direction away from the base substrate, the width of the retaining wall gradually increases (ie, the cross-section of the formed pixel defining layer perpendicular to the base substrate is an inverted trapezoid). Based on this, when the light-emitting functional layer is formed in the opening area of the pixel definition layer, since the width of the retaining wall gradually increases in the direction from close to the base substrate to the direction away from the base substrate, the sidewall of the retaining wall will affect the material of the light-emitting functional layer. Apply stress toward the base substrate, so that when the light-emitting functional layer is formed by the solution process, the material of the light-emitting functional layer is prevented from climbing along the sidewall of the retaining wall during the drying process, so that the thickness of the formed light-emitting functional layer is reduced. uniform. When the substrate is used in an OLED device, the uniformity of light emission of the OLED device is ensured, and the lifespan of the OLED device is improved.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

1 is a schematic structural diagram of forming a pixel definition layer on a base substrate provided by the prior art;

FIG. 2 is a schematic flowchart of a method for preparing a substrate according to an embodiment of the present invention;

3 is a schematic structural diagram 1 of forming a pixel definition layer film on a base substrate according to an embodiment of the present invention;

FIG. 4 is a second structural schematic diagram of forming a pixel definition layer film on a base substrate according to an embodiment of the present invention;

FIG. 5 is a schematic structural diagram 1 of a substrate according to an embodiment of the present invention;

FIG. 6 is a second structural schematic diagram of a substrate provided by an embodiment of the present invention;

FIG. 7( a ) is a schematic structural diagram 1 of forming a pixel defining layer on a base substrate according to an embodiment of the present invention;

FIG. 7( b ) is a second structural schematic diagram of forming a pixel defining layer on a base substrate according to an embodiment of the present invention.

Reference number:

10-substrate; 20-pixel defining layer; 30-light-emitting functional layer; 40-pixel defining layer film; 50-auxiliary particles; 60-TFT driving circuit; 70-flat layer; 80-electrode layer; 801-sub-electrode .

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

An embodiment of the present invention provides a method for preparing a substrate, as shown in FIG. 2 , including:

S100 , as shown in FIG. 3 , a pixel definition layer film 40 is formed on the base substrate 10 ; wherein, the material of the pixel definition layer film 40 includes photoresist, and a hydrophilic material, an elastic material, and a photoresist doped in the photoresist. Auxiliary particles 50; the auxiliary particles 50 are used to release gas during decomposition, and the elastic material is used to expand the pixel defining layer film 40 when the auxiliary particles 50 release gas; the molecular weights of the affinity material, photoresist and elastic material are all greater than The molecular weight of the auxiliary particles 50 .

It should be noted that, first, the material of the base substrate 10 is not limited. For example, the material of the base substrate 10 may be at least one of silicon nitride (SiN _x ), silicon oxide (SiO _x ), or silicon oxynitride (SiO _x N _y ).

Second, how to form the pixel definition layer film 40 on the base substrate 10 is not limited, for example, the pixel definition layer film 40 may be formed on the base substrate 10 by spin coating or spray coating.

Third, the material of the auxiliary particles 50 is not limited, as long as it can release gas during decomposition. In addition, there is no limitation on how to decompose the auxiliary particles 50. The auxiliary particles 50 can be decomposed to release gas during heating. At this time, the auxiliary particles 50 are thermally decomposed materials. The materials of the auxiliary particles 50 can be, for example, azo compounds, wherein the The general structural formula of the compound is R-N=N-R', R can be a hydrocarbon group or an alkali metal, and the hydrocarbon group can specifically be an organic group such as aliphatic hydrocarbon group, acyl group, sulfonyl group, etc. In addition, the thermal decomposition of the auxiliary particles 50 does not affect the pixel defining layer film 40. In the case of other components, the material of the auxiliary particles 50 can also be selected from azide compounds; the auxiliary particles 50 can also be decomposed to release gas when exposed to light, at this time the auxiliary particles 50 are photodecomposition materials, and the material of the auxiliary particles 50 can be, for example, adjacent to each other. nitrogen naphthoquinone compounds.

On this basis, the type of gas released by the auxiliary particles 50 is not limited. In order to prevent the gas released by the auxiliary particles 50 from reacting with the film layer on the substrate and affecting the performance of the film layer on the substrate, the auxiliary particles 50 are preferred in the present invention. The decomposition releases nitrogen (N ₂ ), argon (Ar) or carbon monoxide (CO) and other stable gases. Further preferably, since nitrogen has stable performance and is not easy to react with other materials, the auxiliary particles 50 in the embodiment of the present invention are decomposed to release nitrogen.

The specific material of the elastic material is not limited. Since the elastic material can expand the pixel definition layer film 40 when the auxiliary particles 50 release gas, the elastic material should be a highly elastic material. Exemplarily, the elastic material may include at least one of thermoplastic polyester elastomer, thermoplastic polyurethane elastomer (Thermoplastic polyyrethane, TPU for short) or thermoplastic ethylene propylene diene propylene dynamic vulcanizate (Thermoplastic Vulcanizate, TPV for short). Among them, thermoplastic polyester elastomer (TPEE), also known as polyester rubber, is a kind of linear type containing PBT (polybutylene terephthalate) polyester hard segment and aliphatic polyester or polyether soft segment block copolymer.

The material of the photoresist is not limited, for example, it can include polyimide (Polyimide, PI for short). In addition, the photoresist can be either positive photoresist or negative photoresist.

Here, the hydrophilic material may be a hydrophilic material or a lipophilic material. The affinity material is a rigid polymer, and the specific material of the affinity material is not limited. For example, the affinity material may include polyimide, bisphenol A polycarbonate, a polymer containing an alkyl group in the main chain, and a main At least one of the polymers containing a cyclic rigid structure in the chain. Among them, the polymer containing an alkyl group in the main chain can be, for example, polymers such as polyacrylic acid, polyacrylamide, polyvinyl alcohol, polyurethane, and polyamide, and derivatives thereof. In addition, it should be noted that since polyimide can be used as both a photoresist material and an affinity material, both the photoresist material and the affinity material can be selected from polyimide. When polyimide is selected as the material and the affinity material, the elastic material and auxiliary particles 50 can be added to the polyimide.

Based on the above, the materials of the pixel defining layer film 40 provided by the implementation of the present invention include but are not limited to photoresist, the hydrophilic material doped in the photoresist, the elastic material and the auxiliary particles 50, and may also include other materials such as solvents .

S101 , as shown in FIG. 4 , heating the pixel definition layer film 40 to move the auxiliary particles 50 away from the base substrate 10 .

Wherein, since the molecular weight of the auxiliary particles 50 is smaller than the molecular weight of the photoresist, the elastic material and the affinity material in the material of the pixel definition layer film 40 , when the pixel definition layer film is heated, the auxiliary particles 50 will move away from the base substrate 10 . In this way, as shown in FIG. 4 , the distribution density of the auxiliary particles 50 gradually increases along the direction from approaching the base substrate 10 to the direction away from the base substrate 10 (as shown by the arrow in FIG. 4 ).

Here, when the material of the auxiliary particles 50 is a thermally decomposable material, since the auxiliary particles 50 move in a direction away from the base substrate 10 during the heating process of the pixel defining layer film 40, the auxiliary particles 50 cannot be decomposed. The selected temperature for heating the PDL film 40 should be lower than the thermal decomposition temperature of the auxiliary particles 50 . Preferably, in the embodiment of the present invention, the heating temperature for heating the pixel definition layer film 40 is 30-40°C.

S102 , as shown in FIG. 5 , the pixel definition layer film 40 is processed to form the pixel definition layer 20 , and the auxiliary particles 50 are decomposed to release gas.

Here, when the pixel defining layer film 40 is processed, the auxiliary particles 50 can be decomposed to release gas while the pixel defining layer 20 is formed; the pixel defining layer 20 can also be formed first, and then the auxiliary particles 50 can be decomposed to release gas. Gas, which is not limited.

It should be noted that, since the distribution density of the auxiliary particles 50 gradually increases in the direction from approaching the base substrate 10 to the direction away from the base substrate 10 , the auxiliary particles 50 are released from the direction close to the base substrate 10 to the direction away from the base substrate 10 . The amount of the gas released gradually increases, and the elastic material in the pixel definition layer film 40 can expand the pixel definition layer film 40 when the auxiliary particles 50 release gas. The greater the degree of expansion of the thin film 40 , the greater the degree of expansion of the pixel defining layer 20 in the direction from closer to the base substrate 10 to the direction away from the base substrate 10 . Based on this, when the pixel-defining layer 20 is constituted by a retaining wall, the width of the retaining wall gradually increases along the direction from close to the base substrate 10 to the direction away from the base substrate 10 , that is, the cross-section of the pixel-defining layer 20 perpendicular to the base substrate 10 is Inverted ladder shape.

An embodiment of the present invention provides a method for manufacturing a substrate. When the pixel defining layer 20 is prepared on the base substrate 10, the pixel defining layer thin film 40 includes, in addition to photoresist and affinity material, auxiliary particles 50 and The elastic material, after heating the pixel definition layer film 40, the auxiliary particles 50 in the pixel definition layer film 40 will move in the direction away from the base substrate 10, so that in the direction from close to the base substrate 10 to away from the base substrate 10, The distribution density of the auxiliary particles 50 is gradually increased. Therefore, when the pixel defining layer film 40 is processed and the auxiliary particles 50 are made to release gas, the auxiliary particles 50 are distributed in a direction close to the base substrate 10 and away from the base substrate 10 . The distribution density gradually increases, so the amount of gas released from the decomposition of the auxiliary particles 50 gradually increases along the direction from close to the base substrate 10 to away from the base substrate 10 , so the expansion degree of the pixel defining layer 20 gradually increases. When the pixel defining layer 20 is constituted by a retaining wall, the width of the retaining wall gradually increases along the direction from approaching the base substrate 10 to the direction away from the base substrate 10 (that is, the formed pixel defining layer 20 has an inverted cross section perpendicular to the base substrate 10 ). trapezoid). Based on this, when the light-emitting functional layer 30 is formed in the opening area of the pixel defining layer 20, since the width of the barrier wall gradually increases in the direction from approaching the base substrate 10 to the direction away from the base substrate 10, the sidewalls of the barrier wall will The material of the light-emitting functional layer 30 exerts a stress toward the base substrate 10 (as shown by the arrow in FIG. 5 ), so that when the light-emitting functional layer 30 is formed by a solution process, the material of the light-emitting functional layer 30 is prevented from drying during the drying process. Climb along the side wall of the retaining wall, so that the thickness of the formed light-emitting functional layer 30 is uniform. When the substrate is used in an OLED device, the uniformity of light emission of the OLED device is ensured, and the lifespan of the OLED device is improved.

Based on the above, it should be noted that, before forming the pixel defining layer film 40 on the base substrate 10, as shown in FIG. , a flat layer 70 is formed on the TFT driving circuit 60, the flat layer 70 covers the TFT driving circuit 60, and then an electrode layer 80 is formed on the flat layer 70. The electrode layer 80 includes a plurality of mutually independent sub-electrodes 801, and the sub-electrodes 801 pass through the flat layer. The via holes on 70 are connected to the TFT driving circuit 60 , and each sub-electrode 801 is located in an opening area of the pixel defining layer 20 . Here, the thickness of the flat layer 70 is not limited. Preferably, the thickness of the flat layer 70 is 1 to 10 μm. In addition, how to form the electrode layer 80 is not limited. For example, a conductive film may be sputtered on the flat layer 70, and then a plurality of sub-electrodes 801 may be formed by exposing, developing and etching the conductive film. The material of the sub-electrode 801 may be, for example, a transparent material such as ITO (Indium Tin Oxide, indium tin oxide).

Preferably, step S102 includes:

S200 , exposing and developing the pixel defining layer film 40 to form the pixel defining layer 20 .

It should be noted that, when the photoresist material in the pixel defining layer film 40 is positive photoresist, the exposed positions of the positive photoresist are dissolved after development, and the unexposed positions are retained after development. The defining layer 20 is not exposed to light, so regardless of whether the material of the auxiliary particles 50 is a photodecomposition material or a thermal decomposition material, when preparing the substrate, step S101 can be performed first, as shown in FIG. 4 , and then step S200 can be performed. The pixel defining layer 20 is shown in FIG. 7( a ), that is, after first moving the auxiliary particles 50 in the pixel defining layer film 40 , the distribution density of the auxiliary particles 50 along the direction from close to the base substrate 10 to away from the base substrate 10 Gradually increase, and then expose and develop the pixel-defining layer film 40 to form the pixel-defining layer 20; the step S200 can also be performed first, and the obtained pixel-defining layer 20 is shown in FIG. 7(b), and then the step S101 is performed to obtain the The pixel definition layer shown in 7(a), that is, the pixel definition layer film 40 is first exposed and developed to form the pixel definition layer 20, and then the auxiliary particles 50 in the pixel definition layer 20 are moved, and the auxiliary particles 50 in the pixel definition layer 20 are moved along the direction from the base substrate 10 to the distance away from the substrate. The distribution density of the auxiliary particles 50 gradually increases in the direction of the base substrate 10 .

When the photoresist material in the pixel defining layer film 40 is negative photoresist, the unexposed position of the negative photoresist will be dissolved after development, and the exposed position will remain after development, because the exposed position photoresist will be cured. In this way, the auxiliary particles 50 are not easy to move during heating. Therefore, in the embodiment of the present invention, when the photoresist is a negative photoresist, when the substrate is prepared, step S101 is performed first, and then step S200 is performed.

Here, after the pixel definition layer film 40 is exposed and developed to form the pixel definition layer 20, as shown in FIG. 7(a) and FIG. From the base substrate 10 to the direction away from the base substrate 10 , the widths of the retaining walls are the same, that is, the cross section of the pixel defining layer 20 perpendicular to the base substrate 10 is a rectangle.

S201 , decomposing the auxiliary particles 50 in the pixel defining layer 20 , so that the auxiliary particles 50 are decomposed to release gas.

Here, the decomposition treatment is not limited, as long as the auxiliary particles 50 can be decomposed to release gas. Specifically, the decomposition treatment may be heat treatment or light treatment. When the material of the auxiliary particles 50 is a thermally decomposable material, the auxiliary particles 50 in the pixel defining layer 20 are subjected to heat treatment to decompose the auxiliary particles 50 to release gas. The decomposition temperature is selected accordingly; when the material of the auxiliary particles 50 is a photodecomposition material, the auxiliary particles 50 in the pixel defining layer 20 are subjected to light treatment to decompose the auxiliary particles 50 to release gas. Here, when the auxiliary particles 50 in the pixel defining layer 20 are subjected to illumination treatment, the selected light is related to the auxiliary particles 50. For example, if the auxiliary particles 50 can be decomposed and release gas under ultraviolet light irradiation, then the illumination treatment selects ultraviolet light Light; if the auxiliary particles 50 can be decomposed to release gas under the irradiation of visible light, visible light is selected for the irradiation treatment.

When the photoresist material in the pixel definition layer film 40 is a negative photoresist, the exposed position of the negative photoresist remains after development. If the auxiliary particles 50 in the pixel definition layer film 40 are photodecomposable materials and can Visible light, such as yellow light, decomposes and releases gas, then step S102 includes:

S300 , exposing and developing the pixel defining layer film 40 to form the pixel defining layer 20 , and decomposing the auxiliary particles 50 to release gas.

Since the photoresist material in the pixel defining layer film 40 is a negative photoresist, the exposed position of the negative photoresist remains after development. When the negative photoresist is exposed, the auxiliary particles 50 will be separated when exposed to visible light. The released gas is explained, so when the pixel defining layer 20 is formed, the auxiliary particles 50 will decompose and release the gas, so the auxiliary particles 50 do not need to be decomposed.

Preferably, the pixel defining layer 20 includes an opening area and a pixel defining area for defining the opening area.

After the pixel-defining layer film 40 is processed to form the pixel-defining layer 20 , the above-mentioned preparation method further includes: forming the light-emitting functional layer 30 in the opening area of the pixel-defining layer 20 .

The light-emitting functional layer 30 may further include at least one of a hole injection layer, a hole transport layer, an electron transport layer and an electron injection layer in addition to the light-emitting layer.

In addition, the material of the light-emitting layer is not limited, and it may be an organic light-emitting layer or a quantum dot light-emitting layer.

On this basis, there is no limitation on which process is used to form the light-emitting functional layer 30 in the opening area of the pixel definition layer 20 . For example, a screen printing process or an inkjet printing process may be used to form the light emitting functional layer 30 in the opening area of the pixel definition layer 20 . The light-emitting functional layer 30 .

It should be noted that, when the processing of the pixel defining layer film 40 to form the pixel defining layer 20 includes steps S200 and S201, the light-emitting functional layer 30 may be formed in the opening area of the pixel defining layer 20 after the step S200 and before the step S201. ; or after step S201 , the light-emitting functional layer 30 may be formed in the opening area of the pixel defining layer 20 . Since the light-emitting functional layer 30 is formed first, and then the auxiliary particles 50 in the pixel defining layer 20 are decomposed, so that the auxiliary particles 50 are decomposed to release gas. The process of the expansion of the layer 20 can better inhibit the material of the light-emitting functional layer 30 from climbing along the sidewall of the pixel defining layer 20; The heating treatment is performed to decompose the auxiliary particles 50 to release gas, and at the same time, the light-emitting functional layer 30 is baked, which simplifies the manufacturing process of the substrate. Therefore, in the embodiment of the present invention, preferably, after step S200 and before step S201, in the pixel The opening region of the defining layer 20 forms the light-emitting functional layer 30 . On this basis, after step S200 and before step S201, when the light-emitting functional layer 30 is formed in the opening area of the pixel defining layer 20, when the auxiliary particles 50 are thermally decomposed, the thermal decomposition temperature of the auxiliary particles 50 and For the material of the light-emitting functional layer 30, an appropriate heating temperature of the heating treatment is selected. In addition, the heating treatment may be normal pressure heating or low pressure heating.

Further preferably, forming the light-emitting functional layer 30 in the opening area of the pixel defining layer 20 includes: printing ink containing the material of the light-emitting functional layer in the opening area of the pixel defining layer 20 by using an inkjet printing method.

Since the inkjet printing method has the advantages of high precision and material saving compared with other solution processes such as screen printing, the embodiment of the present invention preferably uses the inkjet printing method to print the ink containing the material of the light-emitting functional layer in the opening area of the pixel defining layer 20, to form the light-emitting functional layer 30 .

An embodiment of the present invention provides a substrate, which is prepared and formed by the above-mentioned preparation method.

It should be noted that when the substrate is prepared and formed by the above-mentioned substrate preparation method, the formed pixel defining layer 20 is as shown in FIG. When the 20 is constituted by a retaining wall, the width of the retaining wall gradually increases along a direction from approaching the base substrate 10 to a direction away from the base substrate 10 .

An embodiment of the present invention provides a substrate. When the pixel defining layer 20 on the substrate is constituted by a retaining wall, the width of the retaining wall gradually increases along the direction from approaching the base substrate 10 to the direction away from the base substrate 10 . When the light-emitting functional layer 30 is formed in the opening area of the defining layer 20 , the sidewall of the retaining wall will exert stress on the material of the light-emitting functional layer 30 toward the base substrate 10 . The material of the light-emitting functional layer 30 climbs along the sidewall of the retaining wall during the drying process, so that the formed light-emitting functional layer 30 has a uniform thickness. When the substrate is used in an OLED device, the uniformity of light emission of the OLED device is ensured, and the lifespan of the OLED device is improved.

Embodiments of the present invention provide and further provide a display device including the above-mentioned substrate.

Wherein, the display device provided by the embodiment of the present invention may be any device that displays an image regardless of motion (eg, video) or fixed (eg, still image), and regardless of text or picture. More specifically, it is contemplated that the embodiments may be implemented in or associated with a wide variety of electronic devices, such as, but not limited to, mobile phones, wireless devices, personal data assistants (PDAs) , handheld or portable computers, GPS receivers/navigators, cameras, MP4 video players, camcorders, game consoles, watches, clocks, calculators, TV monitors, flat panel monitors, computer monitors, automotive monitors (e.g., odometer displays, etc.), navigators, cockpit controls and/or displays, displays of camera views (eg, displays of rear-view cameras in vehicles), electronic photographs, electronic billboards or signs, projectors, building structures, packaging and aesthetic structures (eg, a display for an image of a piece of jewelry), etc. In addition, the display device provided by the embodiment of the present invention may also be a display panel.

Here, when the light-emitting functional layer 30 formed on the substrate includes an organic light-emitting layer, the display device is an organic electroluminescent display device; when the light-emitting functional layer 30 formed on the substrate includes a quantum dot light-emitting layer, the display device is quantum dot light-emitting Display device (Quantum Dot Light Emitting Diodes, referred to as QLED).

It should be noted that, in addition to the above-mentioned substrate, the display device may further include an encapsulation layer or an encapsulation substrate formed on the substrate.

Embodiments of the present invention also provide a display device, the display device includes the above-mentioned substrate, and the substrate in the display device has the same structure and beneficial effects as the substrate provided by the above-mentioned embodiment, because the above-mentioned embodiment has already improved the technical characteristics and beneficial effects of the substrate. The effect has been described in detail, so it will not be repeated here.

The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art can easily think of changes or substitutions within the technical scope disclosed by the present invention. should be included within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (10)

1. A method of preparing a substrate, comprising:

forming a pixel defining layer film on a substrate; wherein, the material of the pixel defining layer film comprises photoresist and hydrophilic material, elastic material and auxiliary particles doped in the photoresist; the auxiliary particles are used for releasing gas when being decomposed, and the elastic material is used for expanding the pixel defining layer film when the auxiliary particles release gas; the molecular weight of the hydrophilic material, the photoresist and the elastic material is larger than that of the auxiliary particles; the hydrophilic material is a hydrophilic material or a lipophilic material;

heating the pixel defining layer film to enable the auxiliary particles to move in a direction away from the substrate base plate;

and processing the pixel defining layer film to form a pixel defining layer, and decomposing the auxiliary particles to release gas.

2. The method according to claim 1, wherein the processing of the pixel defining layer film to form a pixel defining layer and the decomposition of the auxiliary particles to release a gas comprises:

exposing and developing the pixel defining layer film to form a pixel defining layer;

decomposing the auxiliary particles in the pixel defining layer to decompose the auxiliary particles to release gas;

or,

and exposing and developing the pixel defining layer film to form a pixel defining layer, and decomposing the auxiliary particles to release gas.

3. A method according to claim 2, wherein the decomposing treatment of the auxiliary particles in the pixel defining layer to decompose the auxiliary particles to release a gas comprises:

and carrying out heating treatment or light irradiation treatment on the auxiliary particles in the pixel defining layer to decompose the auxiliary particles to release gas.

4. The production method according to claim 1, wherein the pixel defining layer includes an opening region and a pixel defining region for defining the opening region;

after the pixel defining layer thin film is processed to form a pixel defining layer, the preparation method further comprises the following steps: and forming a light emitting function layer in an opening region of the pixel defining layer.

5. The production method according to claim 4, wherein forming a light-emitting function layer in an opening region of the pixel defining layer comprises:

and printing ink containing the material of the luminous function layer on the opening region of the pixel defining layer by using an ink-jet printing method.

6. The production method according to claim 1, wherein the auxiliary particles are azo compound particles.

7. The method of claim 1, wherein the elastomeric material comprises at least one of a thermoplastic polyester elastomer, a thermoplastic polyurethane elastomer, or a thermoplastic ethylene-propylene-diene dynamically vulcanized elastomer.

8. The method according to claim 1, wherein the hydrophilic material comprises at least one of polyimide, bisphenol a polycarbonate, a polymer having an alkyl group in a main chain, and a polymer having a cyclic rigid structure in a main chain.

9. A substrate produced by the production method according to any one of claims 1 to 8.

10. A display device comprising the substrate according to claim 9.

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