KR20170062856A - Organic light emitting display - Google Patents

Abstract

There is provided an organic light emitting display in which the reliability of the sealing layer according to an exemplary embodiment of the present invention is improved. An encapsulation layer comprising an organic light-emitting device on a substrate on which a display area and a non-display area are defined, the encapsulation layer including at least one organic material layer and at least one inorganic material layer, And an organic material control layer surrounding the rim. The organic material layer and the organic material control layer control the surface energy to efficiently arrange the organic material layer in the intended region, thereby improving the reliability of the sealing layer.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to an organic light-

The present invention relates to an organic light emitting diode (OLED) display, and more particularly, to an OLED display including an organic layer for protecting an organic light emitting diode and an organic layer for controlling an arrangement of organic layers in an encapsulation layer of an inorganic layer .

The organic light emitting diode (OLED) is a self-emissive type display device, and unlike a liquid crystal display (LCD), a separate light source is not required, so that it can be manufactured in a light and thin shape. Further, the organic light emitting display device is not only advantageous from the viewpoint of power consumption by low voltage driving, but also excellent in color implementation, response speed, viewing angle, and contrast ratio (CR), and is being studied as a next generation display.

Organic light emitting display devices are very vulnerable to oxygen, moisture and the like because organic materials are used as the light emitting layer. Accordingly, various techniques for sealing the organic light emitting device have been used to minimize penetration of oxygen, water, etc. from the outside into the organic light emitting layer.

Recently, the front bag sealing technique is widely used. The front encapsulation technique is a technique for disposing an encapsulation layer for protecting the organic light emitting element on the substrate on the organic light emitting element and bonding the upper substrate on the encapsulation layer to block the moisture permeation path. An encapsulating layer having a different thickness and a laminated structure may be used.

An encapsulating layer having a structure in which an inorganic material layer made of an inorganic material and an organic material layer made of an organic material are alternately stacked is used as an encapsulating layer mainly used for a front encapsulating technique.

The inorganic layer made of an inorganic material may be composed of an aluminum (Al) -based or silicon (Si) -based carbonized compound, a nitrated compound, or an oxidized compound, and mainly functions to block the penetration path of oxygen and moisture.

The organic material layer made of an organic material may be made of an epoxy-based or acrylic-based polymer. The organic absorber layer blocks the penetration path of oxygen and moisture but functions to cover the particles on the substrate while compensating the rigidity of the inorganic layer while slowing the penetration speed.

The inorganic layer may be disposed by using a chemical vapor deposition method such as CVD, and the organic layer may be disposed by a method of applying in a vacuum state using a mask.

In the case of using a sealing technique comprising the inorganic layer and the organic material layer, a moisture permeation path may occur when a crack of the inorganic material layer occurs on the side surface, and a moisture permeation path through the organic material layer may occur on the side surface of the substrate.

Accordingly, recently, a technique has been used in which an inorganic layer is disposed, an organic layer is disposed narrower than an inorganic layer, and an additional inorganic layer is disposed so as to cover the organic layer to block the moisture permeation path through the side surface of the organic layer.

A sealing technique using an inorganic layer and an organic material layer is used as a front sealing technique that seals an organic light emitting element to minimize penetration of oxygen and moisture.

The encapsulating layer of the front encapsulation technique is thin and has an excellent effect of effectively preventing the penetration of oxygen and moisture.

The inorganic layer included in the encapsulation layer is deposited using a chemical vapor deposition method such as CVD as described above and the organic layer is formed by a method of applying an organic substance such as a polymer on the inorganic layer by using a mask in a vacuum .

At this time, the organic material such as the polymer used as the organic material layer has a relatively low viscosity, and it is very difficult to apply the organic material in a uniform thickness in the process of coating.

In order to uniformly form such a polymer, a dam structure for controlling the flow property is disposed on the edge of the organic light emitting display device. The dam structure is made of the same material as that of the flat layer or the bank layer included in the organic light emitting display And is placed in the border area.

However, as the organic light emitting display device has grown in size, the organic material deposition method of the inkjet method has been introduced, and organic materials having a lower viscosity have been used. As a result, it is difficult to control the flowability of the organic material by the dam structure alone. Accordingly, the inventors of the present invention have invented a new structure of an organic light emitting display capable of improving the reliability of the sealing layer by more effectively controlling the fluidity of the organic material.

An object of the present invention is to provide an organic light emitting diode (OLED) display device capable of improving the lifetime reliability by efficiently controlling the arrangement of organic layers and minimizing the moisture permeation path that can be generated in the side.

An object of the present invention is to provide an organic light emitting diode (OLED) display device capable of minimizing screen unevenness because the organic material layer can have a low viscosity because organic materials having low viscosity can be used as an organic material layer.

The solutions according to one embodiment of the present invention are not limited to the above-mentioned problems, and other problems not mentioned can be clearly understood by those skilled in the art from the following description.

There is provided an organic light emitting display device capable of efficiently controlling the arrangement of organic layers according to one example of the present invention. There are a plurality of organic light emitting elements on a substrate, and a display area and a non-display area are defined. An encapsulation layer having at least one inorganic layer and at least one organic layer for protecting the organic light emitting element is disposed on the front surface to cover the organic light emitting element. At this time, since the organic material layer is made of a material having a lower surface energy than the inorganic material layer, the organic material layer can be uniformly arranged on the substrate while minimizing the aggregation of the organic material layers on the substrate. In addition, when the organic material control layer made of a material having a surface energy higher than that of the inorganic material layer is disposed in the non-display region, the flowability of the organic material is controlled by the energy difference when the organic material layer of the sealing layer is formed, .

The inorganic layer may be composed of a silicon (Si) -based or aluminum (Al) -based carbonized compound, a nitrated compound or an oxidized compound.

The organic material layer may be an epoxy-based or acrylic-based polymer.

The organic material layer may have a functional group that lowers the surface energy in consideration of the material of the inorganic material layer.

At this time, the functional group may be an OH group.

The organic material layer may be made of a material having an inorganic material layer and a contact angle of 5 to 40 degrees.

The viscosity of the organic layer may be 8 to 30 cp.

The organic layer may be a material that is cured by methods such as UV curing, thermal curing, or UV-thermal hybrid curing.

The organic material control layer may be an epoxy-based or acrylic-based polymer.

The thickness of the organic material control layer may be substantially the same as the thickness of the organic material layer, or the error range may be within 30%.

The organic material control layer may have a functional group that increases the surface energy in consideration of the material of the inorganic layer.

Here, the functional group may be a functional group selected from a C group or an H group.

The organic material control layer may be made of a material having a contact angle of at least 50 degrees with the inorganic material layer.

The width of the organic material control layer may be 50 占 퐉 or more.

The organic light emitting display may further include a dam structure in a non-display area.

The dam structure may be a polyimide-based material.

There is provided an organic light emitting display device having a sealing layer with improved reliability according to an embodiment of the present invention. There is an organic light emitting element on a substrate, and a sealing layer which forms a front sealing with respect to the organic light emitting element. The sealing layer includes an organic sealing layer composed of an organic substance layer composed of a polymer having a low viscosity capable of using an inkjet method and an organic substance control layer surrounding the organic substance layer, A display device can be provided.

The organic sealing layer may be an epoxy-based or acrylic-based polymer.

The organic layer may have a functional group that lowers the surface energy.

The organic material control layer may have a functional group that increases the surface energy.

The organic light emitting diode display may further include an inorganic encapsulation layer forming a front encapsulation with respect to the organic light emitting element.

According to the embodiment of the present invention, there is an effect that the reliability of the sealing layer can be improved by providing the organic substance control layer capable of effectively controlling the flowability of the organic substance layer.

Also, since the organic light emitting display has the organic material control layer, the uniformity of the thickness of the organic material layer can be controlled more effectively, thereby minimizing the screen unevenness of the organic light emitting display device.

The effects of the present invention are not limited to the effects mentioned above, and other effects not mentioned can be clearly understood by those skilled in the art from the following description.

The scope of the claims is not limited by the matters described in the contents of the invention, as the contents of the invention described in the problems, the solutions to the problems and the effects to be solved do not specify essential features of the claims.

FIG. 1 is a schematic plan view illustrating an organic light emitting display device having an organic material control layer according to an embodiment of the present invention. Referring to FIG.
FIG. 2 is a schematic cross-sectional view according to AA 'of FIG. 1 for illustrating an organic light emitting display device having an organic material control layer and an organic material layer according to an embodiment of the present invention.
3 is a schematic cross-sectional view of an organic light emitting diode display having a plurality of inorganic layers and a plurality of organic layers according to an embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The advantages and features of the present invention and the manner of achieving them will become apparent with reference to the embodiments described in detail below with reference to the accompanying drawings. The present invention may, however, be embodied in many different forms and should not be construed as being 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 scope of the invention to those skilled in the art. Is provided to fully convey the scope of the invention to those skilled in the art, and the invention is only defined by the scope of the claims.

The shapes, sizes, ratios, angles, numbers, and the like disclosed in the drawings for describing the embodiments of the present invention are illustrative, and thus the present invention is not limited thereto. Like reference numerals refer to like elements throughout the specification. In the following description, well-known functions or constructions are not described in detail since they would obscure the invention in unnecessary detail. Where the terms "comprises", "having", "done", and the like are used in this specification, other portions may be added unless "only" is used. Unless the context clearly dictates otherwise, including the plural unless the context clearly dictates otherwise.

In interpreting the constituent elements, it is construed to include the error range even if there is no separate description.

In the case of a description of the positional relationship, for example, if the positional relationship between two parts is described as 'on', 'on top', 'under', and 'next to' Or " direct " is not used, one or more other portions may be located between the two portions.

It is to be understood that each of the features of the various embodiments of the present invention may be combined or combined with each other, partially or wholly, technically various interlocking and driving, and that the embodiments may be practiced independently of each other, It is possible.

Various embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

FIG. 1 is a schematic plan view illustrating an organic light emitting display device having an organic material control layer according to an embodiment of the present invention. Referring to FIG.

1, an organic light emitting diode display 100 includes a substrate 110 having a display region 120 and a non-display region 130 defined therein, an encapsulation layer 140 disposed on the substrate 110, A connection electrode 160, a pad electrode 170, and a driver IC 180.

1, a plurality of pixels (not shown) are disposed in a display region 120 defined in the substrate 110, and organic light emitting devices (not shown) are disposed for each pixel.

An organic light emitting device (not shown) is connected to the driver IC 180 and the pad electrode 170 to receive driving signals and current for driving individual pixels.

The substrate 110 may be a glass substrate or a flexible substrate composed of polyimide, but is not limited thereto. The substrate 110 may further include a barrier layer.

An organic light emitting device (not shown) disposed on the substrate 110 uses an organic material as a light emitting layer and emits light by receiving current through two electrodes. Here, the organic material used as the light emitting layer may cause oxidation phenomenon at the interface with the electrode due to oxygen and moisture, which may cause defects such as a dark spot, and a progressive dark spot where defects such as generated spot can be enlarged have.

In order to minimize such defects, the permeation of oxygen and moisture should be minimized, and the sealing layer 140 is disposed on the substrate 110 to minimize permeation of oxygen and moisture.

The sealing layer 140 may be an encapsulation layer 140 including an organic material layer made of an organic material and an inorganic material layer made of an inorganic material, and may have a multi-layer structure of a repeating structure of an organic material and an inorganic material.

Materials that can be used as the inorganic layer include silicon-based or aluminum-based materials such as silicon nitride (SiNx) and aluminum oxide (AlOx), which have good step coverage and are dense in density and can minimize penetration of oxygen and moisture. , A nitrifying compound or an oxidizing compound may be used.

Epoxy-based or acrylic-based polymers may be used as the organic material layer. The organic layer functions to slow the penetration rate of oxygen and hydrogen, and may include a getter capable of adsorbing oxygen and hydrogen therein.

The inorganic layer that can be used as the sealing layer 140 can be disposed by a method such as CVD or the like. In the case of the organic layer, the inorganic layer can be disposed by a printing method using a mask.

In recent years, it is preferable to use an organic material having a viscosity of 8 to 30 cp (centipoise) in order to arrange the organic material layer using an inkjet process in accordance with the trend toward enlargement and refinement.

In the case of an organic material having a low viscosity, a droplet phenomenon may occur due to a surface tension due to a difference in surface energy when the organic material is disposed on the substrate 110, and organic materials may not be uniformly arranged. Therefore, an organic material having a functional group that lowers the surface energy can be used in consideration of the surface on which the organic material is disposed (for example, when the organic material is disposed on the inorganic material layer or on the organic light emitting device).

Since the organic material having such a low viscosity is used, the organic material disposed on the substrate 110 may undergo a phenomenon such as flow due to gravity. Accordingly, the organic material control layer 150 may be disposed on the substrate 110 to control the placement of organic materials in unintended areas.

The organic material control layer 150 may be disposed in the non-display area 130, which is an area other than the display area 120 defined in the substrate 110, in consideration of a margin considering a uniform arrangement of the organic materials.

The sealing layer 140 including the inorganic layer and the organic material layer and the organic material control layer 150 will be described in detail below.

2 is a schematic cross-sectional view taken along line A-A of FIG. 1 for illustrating an organic light emitting display device having an organic material control layer and an organic material layer according to an embodiment of the present invention.

2, the OLED display 200 includes an encapsulation layer 240 that encapsulates the organic light emitting device 211 on a substrate 210 on which a display region 220 and a non-display region 230 are defined. . The sealing layer 240 includes an inorganic layer 241 made of an inorganic material and an organic layer 242 made of an organic material. Since the organic light emitting diode display 200 includes the dam 290 configured to control the arrangement area of the organic layer 242 and the arrangement area of the organic layer 242 can not be effectively controlled only by the dam 290, 290 and an organic material control layer 250 disposed adjacent to the organic material layer.

The substrate 210 may be a glass substrate or a flexible substrate composed of polyimide, but is not limited thereto.

A barrier layer may be disposed on the upper or lower surface of the substrate 210 to further block oxygen and moisture permeating through the substrate 210.

2, the organic light emitting device portion 211 disposed on the substrate 210 may include a driving device for driving the organic light emitting device and an organic light emitting layer disposed between the two electrodes.

As described with reference to FIG. 1, the organic light emitting device including the organic light emitting layer is vulnerable to oxygen and moisture, so that when oxygen and hydrogen penetrate, defects such as a dark spot or a progressive dark spot may occur.

In order to minimize such defects, a sealing layer 240 sealing the organic light emitting element portion 211 is disposed.

The sealing layer 240 includes an inorganic material layer 241 made of an inorganic material and an organic material layer 242 made of an organic material to minimize penetration of oxygen and moisture.

The inorganic layer 241 may be made of silicon-based, aluminum-based carbonization, nitriding, or an oxidation compound. The inorganic layer 241 is disposed so as to cover the entire surface of the display region 220 of the substrate 210 so as to seal the organic light emitting element portion 211 from penetration of oxygen and hydrogen, As shown in Fig.

The inorganic layer 240 made of an inorganic material is vulnerable to impact and pressure, which can cause micro cracks when impact and pressure are applied.

The fine cracks develop into progressive cracks over time, and the cracks progress to the display area 220 of the organic light emitting display 200, so that an infiltration path that allows oxygen and hydrogen to penetrate can be generated.

Thus, an organic material layer 242 made of an organic material is disposed on the inorganic material layer 241.

The organic material layer 242 may be made of an epoxy-based or acrylic-based polymer and disposed at a uniform height on the inorganic layer 241. That is, the organic material layer 242 can uniformly planarize the upper surface of the substrate 210.

The organic material layer 242 is disposed using an organic material having a viscosity of 8 to 30 cp so that the organic material layer 242 can be disposed by an inkjet method.

In general, when an organic material having a low viscosity is arranged by an inkjet method, it is difficult to arrange the organic material layer 242 so as to have a uniform thickness due to the flowability of the organic material and the surface tension. Therefore, the organic material used for the inorganic material layer 241 Organic materials with functional groups that lower energy are used. That is, the organic material layer 242 is made of a material whose surface energy is lower than that of the inorganic material layer 241.

As a functional group for lowering the surface energy, a polymer having a functional group such as OH can be used.

The organic material layer 242 has a contact angle of 5 to 40 degrees with the inorganic material layer 241 when the organic material whose surface energy is lowered in consideration of the material of the inorganic material layer 241 is disposed on the inorganic material layer 241. [

Accordingly, the organic material layer 242 has hydrophilicity on the inorganic material layer 241 and the organic material layer 242 having a uniform height can be disposed according to the surface energy having a relatively low contact angle.

However, when the organic material layer 242 having hydrophilicity is disposed on the inorganic material layer 241, the organic material is disposed over the dam 290 of the non-display area 230 including the display area 220 because the flowability of the organic material is high. .

However, if the organic material control layer 250 is disposed on the inorganic material layer 241 at a width of 50 μm or more adjacent to the dam 290 by using an organic material whose surface energy is increased in consideration of the material of the inorganic material layer 241, (242) is not disposed beyond the organic material control layer (250).

The inorganic layer 241 and the hydrophilic organic layer 242 are disposed on the inorganic layer 241 and the inorganic layer 241 and the organic material control layer 250 composed of the hydrophobic organic layer are formed on the inorganic layer 241, The organic material layer 242 has a low surface energy and the organic material control layer 250 has a high surface energy so that the organic material layer 242 is not disposed over the organic material control layer 250.

The organic material control layer 250 is made of a polymer having a functional group having a surface energy higher than that of the inorganic material layer 241 so that the organic material control layer 250 has a contact angle of 50 ° or more with the inorganic material layer 241, Layer.

As the functional group for increasing the surface energy of the organic material control layer 250, a polymer having a functional group selected from the group C or H can be used. The thickness of the organic substance control layer 250 may be substantially equal to the thickness of the wet season water layer 242, or the error range may be within 30%.

Accordingly, the organic material layer 242 is disposed on the inorganic layer 241 in an ink-jet manner on a region intended to have a uniform height, and is formed by UV curing, thermal curing or UV-thermal hybrid curing By weight.

In summary, in order to uniform the height of the organic material layer 242 while controlling the flowability of the organic material in the arrangement of the sealing layer 240 using the organic material having a low viscosity as described above, the organic material control layer 250 is formed in the organic material layer The organic material layer 242 is disposed to surround the organic material layer 242 by using a polymer having a functional group such as an OH group so that the organic material layer 242 has hydrophilicity by lowering surface energy. Or an H group, so that the organic light emitting display 200 having the highly reliable sealing layer 240 can be provided.

3 is a schematic cross-sectional view of an organic light emitting diode display having a plurality of inorganic layers and a plurality of organic layers according to an embodiment of the present invention.

3, the organic light emitting diode display 300 includes an organic light emitting diode part 311 and an encapsulation layer 340 on a substrate 310 on which a display area 320 and a non-display area 330 are defined do.

Hereinafter, substantially the same or similar components as those of FIG. 2 will be omitted.

The sealing layer 340 includes an inorganic material layer 341 made of an inorganic material and an organic material layer 342 made of an organic material. The sealing layer 340 is disposed in a repeated stacked structure in which an inorganic material and an organic material are repeatedly laminated.

At this time, the organic material control layer 350 for controlling the arrangement of the organic materials is disposed so as to surround the rim of each organic material layer 342. Thus, each organic material layer 342 can be controlled in its arrangement region by the organic material control layer 350.

Although the embodiments of the present invention have been described in detail with reference to the accompanying drawings, it is to be understood that the present invention is not limited to those embodiments and various changes and modifications may be made without departing from the scope of the present invention. . Therefore, the embodiments disclosed in the present invention are intended to illustrate rather than limit the scope of the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. Therefore, it should be understood that the above-described embodiments are illustrative in all aspects and not restrictive. The scope of protection of the present invention should be construed according to the claims, and all technical ideas within the scope of equivalents should be interpreted as being included in the scope of the present invention.

100, 200, 300: organic light emitting display
110, 210 and 310:
120, 220, 320: display area
130, 230, 330: non-display area
140, 240, 340: sealing layer
150, 250, 350: organic control layer

Claims (21)

A substrate having an organic light emitting element and defining a display region and a non-display region;
An organic material control layer in the non-display area; And
An encapsulant comprising at least one inorganic layer and at least one organic layer,
Wherein the organic material layer is made of a material having a surface energy lower than that of the inorganic material layer,
Wherein the organic material control layer is made of a material having a higher surface energy than the inorganic material layer. The method according to claim 1,
Wherein the inorganic layer is made of a silicon (Si) -based or aluminum (Al) -based carbon compound, a nitride compound or an oxide compound. The method according to claim 1,
Wherein the organic material layer is an epoxy-based or acrylic-based polymer. The method of claim 3,
Wherein the organic material layer has a functional group that lowers the surface energy in consideration of the material of the inorganic material layer. 5. The method of claim 4,
Wherein the functional group is an OH group. 5. The method of claim 4,
Wherein the organic material layer is made of a material having a contact angle of 5 to 40 占 with the inorganic material layer. The method of claim 3,
And the viscosity of the organic material layer is 8 to 30 cp. The method of claim 3,
Wherein the organic material layer is a material that is cured by a method of UV curing, thermal curing, or UV-thermal hybrid curing. The method according to claim 1,
Wherein the organic material control layer is an epoxy-based or acrylic-based polymer. 10. The method of claim 9,
Wherein the thickness of the organic material control layer is substantially equal to or less than the thickness of the organic material layer. 10. The method of claim 9,
Wherein the organic material control layer has a functional group that increases the surface energy in consideration of the material of the inorganic material layer. 12. The method of claim 11,
Wherein the functional group is a functional group selected from the group C or the group H. 12. The method of claim 11,
Wherein the organic material control layer is made of a material having a contact angle of 50 DEG or more with the inorganic material layer. 10. The method of claim 9,
Wherein the organic material control layer has a width of 50 mu m or more. The method according to claim 1,
And a dam structure in the non-display area. 16. The method of claim 15,
Wherein the dam structure is a polyimide-based material. A substrate having an organic light emitting device;
And an organic sealing layer composed of an organic material layer made of a low viscosity polymer of an inkjet method forming a front encapsulation with respect to the organic light emitting device and an organic material control layer surrounding the organic material layer. 18. The method of claim 17,
Wherein the organic sealing layer is an epoxy-based or acrylic-based polymer. 19. The method of claim 18,
Wherein the organic layer has a functional group that lowers the surface energy. 19. The method of claim 18,
Wherein the organic material control layer has a functional group for increasing surface energy. 18. The method of claim 17,
And an inorganic encapsulation layer forming a front encapsulation with respect to the organic light emitting device.

Images