KR100300425B1 - Plastic base plate used in organic electro luminescence display - Google Patents

Abstract

PURPOSE: This invention relates to a plastic substrate for organic electroluminescent devices of a novel structure in which a variety of functional films are laminated to reduce chemical deformation and improve moisture resistance and breathability.

Composition: a base layer to which one of polymers such as PET, PEN, PES, PC and PAR is applied, and a layer laminated on the upper front surface of the base layer and to which at least one of a solvent barrier, a hard coat, an overcoat and a smooth film is applied It is a multilayer structure which consists of a 1st protective layer and the 1st gas barrier layer laminated | stacked on the upper whole surface of the said 1st protective layer, and to which the gas barrier of organic substance or inorganic substance is applied. In addition, the inside of the cell is used as a rear substrate to remove impurities remaining and generated in the cell, and may further include a structure in which a getter layer is stacked on the first gas barrier layer.

Effect: As described above, the present invention improves breathability, moisture resistance, chemical resistance, and the like, and can remove impurities in the cell, thereby improving the life of the organic EL device, and advantageous for flattening the film. Can improve the reliability.

Description

Plastic base plate used in organic electroluminescence display

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic substrate for organic electroluminescent devices, and more particularly to a plastic substrate for organic electroluminescent devices having a novel structure formed by stacking various functional films which can reduce chemical deformation and improve moisture resistance and breathability.

As is well known, the organic electroluminescent device uses an organic phosphor as the center of light emission using an organic thin film, and it is possible to realize high luminance with a low voltage of about V compared to the inorganic electroluminescent device and to improve luminous efficiency. On the other hand, it has the disadvantage of short life and narrow operating temperature range.

In the organic EL device, as shown in FIG. 3, the transparent electrode 21 is stacked on the front substrate 12, and the hole transport layer 23a, the light emitting layer 23b, and the electron transport layer 23c are disposed thereon as the organic light emitting layer. ), The metal electrode 25 and the protective layer 27 are sequentially stacked, and the back substrate 14 having the gas injection holes 142 formed thereon is epoxy molded and shielded, and then argon gas is passed through the gas injection holes 142. After injection, the cover 144 is molded.

In the organic EL device having such a structure, when a predetermined potential difference is provided between the transparent electrode 21 and the metal electrode 25, holes injected into the hole transport layer 23a and electrons injected into the electron transport layer 23c are recombined. The remaining energy is emitted as light.

As the front substrate 12 and the shield substrate of the organic EL device, a glass substrate or a plastic substrate is used.

The plastic substrate is mainly formed of a synthetic resin such as PET, PEN, PES, and is advantageous in thinning the display device compared to the glass substrate, and in particular, when the front substrate 12 is made of plastic, the flexible characteristics of the plastic material can be utilized. It has the advantage of being able to manufacture the display device by a roll to roll process.

However, in the related art, when the plastic substrate is applied to the front substrate 12 and the rear substrate 14 of the organic electroluminescent device, the plastic film itself is poor in breathability and moisture resistance, thereby deteriorating the life of the organic electroluminescent device. Because of the softness, damage may occur easily during the process or during use, and the front substrate 12 may be easily broken by the pressure applied from the outside of the transparent electrode 21 stacked thereon.

In addition, there is a problem that some deformation occurs in the plastic substrate by the chemicals used in the process, such as the film forming process of the transparent electrode 21 and the metal electrode 25 or the cleaning of the substrate.

On the other hand, the conventional organic electroluminescent device has a problem in that impurities such as polymer and gas are generated in the cell interior (G) space shielded in the rear substrate 14 during the light emission reaction, which shortens the life of the product. .

The present invention devised to solve such a conventional problem is an object of the present invention to provide a plastic substrate of an organic EL device laminated with a multi-functional film that can solve the conventional problems described above.

According to the present invention for achieving the above object is a base layer to which one of the polymers, such as PET, PEN, PES, PC and PAR is applied, laminated on the upper front surface of the base layer and the solvent barrier, hard coat, overcoat and An organic electroluminescent device comprising a multi-layered structure comprising a first protective layer to which one of the smoothing films is applied, and a first gas barrier layer to which a gas barrier of an organic material or an inorganic material is applied and stacked on the entire upper surface of the first protective layer. A plastic substrate is provided.

In the structure of the present invention, a second protective layer to which at least one of a solvent barrier and a hard coat is applied is further formed below the base layer, or between the base layer and the second protective layer. The gas barrier layer may be formed by stacking a second gas barrier layer to which a gas barrier of the same material as the gas barrier of the first gas barrier layer is applied. The plastic substrate of such a structure can be used as a front substrate.

On the other hand, the present invention can be used as a back substrate of the organic electroluminescent device by manufacturing a plastic substrate having a structure in which a getter layer is further laminated on the plastic substrate having the above-described structure. That is, the inside of the cell is used as a rear substrate for absorbing and removing impurities remaining in the cell and generated. The getter layer may be stacked on the first gas barrier layer.

1A-1C are tomographic views of a plastic substrate in accordance with various embodiments of the present invention.

2 is a tomogram of a plastic substrate according to another embodiment of the present invention;

3 is a single-layer structure diagram of a general organic EL device to which the present invention is applied

Explanation of symbols on the main parts of the drawings

12-front substrate 12a-base layer

12b-first protective layer 12c-first gas barrier layer

12d-second protective layer 12e-second gas barrier layer

14-back substrate 14f- getter layer

21-transparent electrode 23a-hole transport layer

23b-emitting layer 23c-electron transport layer

25-metal electrode 27-protective layer

Hereinafter, the present invention will be described in more detail with reference to the accompanying drawings.

1A to 1C are tomographic views showing the configuration of various embodiments of the present invention. For reference, the upper side shown is the rear side and the lower side corresponds to the front side.

The reference numeral 14 is a transparent electrode 21 used as an anode of the organic electroluminescent device, the organic electroluminescent device is a hole transport layer 23a, the light emitting layer 23b shown in FIG. ), The electron transport layer 23c, the metal electrode 25 and the protective layer 27 are laminated, and the back substrate 14 is epoxy molded and shielded for tight maintenance such as vacuum thereon. In addition, a gas injection hole 142 for argon gas injection is formed in the rear substrate 14, and a cover 144 for sealing after gas injection is epoxy molded.

In this way, it serves as a base substrate for forming the metal electrode 25 from the transparent electrode 21, the plastic substrate is moisture-resistant to the base layer 12a to which PET, PEN, PES, PC and PAR can be applied. It is made by stacking a plurality of layers having respective functionalities that can achieve air resistance, breathability, chemical resistance, and hardness enhancement.

The structure can be implemented in the following three embodiments.

First embodiment

Referring to FIG. 1A, a base layer 12a to which one of PET, PEN, PES, PC, and PAR is applied may have a first protective layer 12b to which one of a solvent barrier, a hard coat, an overcoat, and a smooth film is applied. ), And then, the plastic substrate according to the embodiment of the present invention so as to have a structure in which a first gas barrier layer 12c to which a gas barrier of an organic material or an inorganic material is applied is stacked on the entire upper surface of the first protective layer 12b. To prepare.

Referring to the operation and effect of the first embodiment configured as described above, the solvent barrier of the first protective layer 12b prevents chemical invasion of the transparent electrode 21 and other films that are stacked on top to prevent chemical invasion. The hard coat prevents the upper transparent electrode 21 from being broken by contact with the outside, and the overcoat and the smoothing film function to planarize the upper transparent electrode 21. .

The gas barrier of the first gas barrier layer 12c serves to prevent oxidation of the upper metal electrode 25 by preventing the invasion of moisture, oxygen, etc. from the outside. It may be formed by sputtering in the case of an inorganic substance.

On the other hand, the present invention can be configured to further complement the structure of the plastic substrate according to the first embodiment.

Second embodiment

That is, the plastic substrate according to the second embodiment of the present invention is manufactured by further laminating a second protective layer 12d to which one of a solvent barrier and a hard coat is applied below the base layer 12a of the first embodiment. do.

Referring to the effect of the second embodiment configured as described above, the solvent barrier of the second protective layer 12d prevents the bay layer from being deformed by chemicals, and the hard coat has a base layer ( 12a) to prevent damage.

In addition, according to the present invention, the plastic substrate may be manufactured by further supplementing the functionality as in the following third embodiment.

Third embodiment

That is, between the base layer 12a and the second protective layer 12d, a second gas barrier layer 12e to which a gas barrier of the same material as that of the gas barrier of the first gas barrier layer 12c is applied is applied. It can form in the structure interposed.

Referring to the operation and effect of the third embodiment configured as described above, the gas barrier of the second gas barrier layer 12e is to enhance the function of the gas barrier of the first gas barrier layer 12c. Forming the gas barrier of the barrier layer 12e with the same material as the gas barrier of the first gas barrier layer 12c is to prevent deformation of the substrate such as bending due to a difference in thermal expansion coefficient.

The structure of the three embodiments described above is a structure of the front plastic substrate on which the transparent electrode 21 is formed, but the present invention can be applied to the back substrate 14 without being limited thereto.

A structure capable of implementing a function for removing impurities inside the cell G may be used as the back substrate 14 described above with reference to FIG. 3. This will be described through the following fourth embodiment.

Fourth embodiment

FIG. 2 shows a structure in which the getter layer 14f is further stacked on the same multilayer 14a, 14b, and 14c structure as the structure of the first embodiment with reference to FIG. 1A of the above three embodiments.

The getter layer 14f functions to remove outgassing impurities such as polymer and gas remaining and generated in the cell G during the light emission reaction due to the recombination of electrons and holes. And V may be used as a single material or a composite material.

Meanwhile, the present invention combines the plastic substrates 12 and 14 according to the four embodiments described above with the cells provided with the transparent electrodes 21 to the metal electrodes 25. Without limiting the direction, the organic electroluminescent display device can be manufactured by attaching it opposite to the directions of the four embodiments described above.

As described above, the present invention improves air resistance, moisture resistance, chemical resistance, and the like, and can remove impurities in the cell, thereby improving the lifespan of the organic EL device, and advantageous in flattening the film, thereby improving product reliability. There is an effect to improve the.

On the other hand, the present invention is not limited to the specific preferred embodiment, it is a matter of course that a variety of applications are possible by ordinary knowledge in the art within the technical rights described in the claims.

Claims (5)

A base layer 12a to which one of polymers such as PET, PEN, PES, PC, and PAR is applied; A first protective layer 12b laminated on the entire upper surface of the base layer 12a and to which at least one of a solvent barrier, a hard coat, an overcoat, and a smooth film is applied; The plastic substrate of the organic electroluminescent device, characterized in that the multi-layer structure consisting of a first gas barrier layer (12c) is laminated on the entire upper surface of the first protective layer (12b) is applied a gas barrier of organic or inorganic. 2. The plastic substrate of the organic electroluminescent device according to claim 1, wherein the second protective layer 12d to which at least one of a solvent barrier and a hard coat is applied is stacked below the base layer 12a. . The second gas barrier layer 12e of claim 2, wherein a gas barrier made of the same material as the first gas barrier layer 12c is applied between the base layer 12a and the second protective layer 12d. A plastic substrate of an organic light emitting device, characterized in that the laminated structure via a). The plastic substrate of an organic electroluminescent element according to any one of claims 1 to 3, which is for the front substrate (12) in the viewing-side direction in which the film of the transparent electrode (21) as an anode is formed. The method according to any one of claims 1 to 3, wherein the inside of the cell G is used as a back substrate 14 for shielding impurities, and the impurities remaining and generated in the inside of the cell G are removed. A plastic substrate of an organic electroluminescent device, characterized in that the getter layer (14f) is laminated on the gas barrier layer (12c).