WO2009028762A1 - Surface treatment material, a film coated with the surface treatment material, and an organic light emitting diode having the film - Google Patents
Surface treatment material, a film coated with the surface treatment material, and an organic light emitting diode having the film Download PDFInfo
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- WO2009028762A1 WO2009028762A1 PCT/KR2007/005558 KR2007005558W WO2009028762A1 WO 2009028762 A1 WO2009028762 A1 WO 2009028762A1 KR 2007005558 W KR2007005558 W KR 2007005558W WO 2009028762 A1 WO2009028762 A1 WO 2009028762A1
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B33/00—Electroluminescent light sources
- H05B33/02—Details
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B33/00—Electroluminescent light sources
- H05B33/10—Apparatus or processes specially adapted to the manufacture of electroluminescent light sources
-
- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05B—ELECTRIC HEATING; ELECTRIC LIGHT SOURCES NOT OTHERWISE PROVIDED FOR; CIRCUIT ARRANGEMENTS FOR ELECTRIC LIGHT SOURCES, IN GENERAL
- H05B33/00—Electroluminescent light sources
- H05B33/12—Light sources with substantially two-dimensional radiating surfaces
- H05B33/22—Light sources with substantially two-dimensional radiating surfaces characterised by the chemical or physical composition or the arrangement of auxiliary dielectric or reflective layers
Definitions
- the present invention relates to a surface treatment material for reacting with a glass substrate of a display device, a surface treatment film coated with such a surface treatment material, and an organic light emitting diode with such a surface treatment film. More particularly, the present invention relates to a surface treatment material for attaching to a surface of a glass substrate of a display device, such as an organic light emitting display (OLED) , and reacting with a component of the glass substrate to form fine projections or grooves on the surface, a surface treatment film, one side of which is coated with such a surface treatment material for a glass substrate, and an OLED that minimizes loss of light emitted through a glass substrate by means of such a surface treatment film adhered to the glass substrate, and thereby can provide light of high luminance .
- OLED organic light emitting display
- an OLED is a self- luminescent display device using a phenomenon that electrons and holes injected from negative and positive electrodes are recombined with each other in an organic film to generate excitons, and energy from the excitons leads to emission of light of a specific wavelength.
- This OLED has advantages in that it requires no additional surface light source, such as a backlight unit, because of its self-luminescence, and have a wide viewing angle, a high response speed, and a small thickness.
- FIG. 1 illustrates the structure of a typical OLED.
- the typical OLED is fabricated by depositing an ITO metal in a given pattern on a glass substrate 1 to form an anode electrode 2 to which a positive power supply is applied, depositing a specific chromophore-containing organic material on the anode electrode 2 to form an organic electroluminescent unit 3 that emits light by a flow of current, and then depositing a cathode-forming material, that is, an electrode material, such as aluminum (Al) , magnesium (Mg) and so forth, on an upper surface of the organic electroluminescent unit 3 to form a cathode electrode 4.
- an electrode material such as aluminum (Al) , magnesium (Mg) and so forth
- the organic material forming the organic electroluminescent unit 3 comes into contact with moisture or oxygen in air, its performance and lifetime significantly deteriorate.
- a sealing cover 5 with a built-in getter 6 is adhered to one side of the glass substrate 1 by means of an adhesive 7 in such a manner as to hermetically seal the side on which the organic material is formed. In this way, the OLED is completed.
- the OLED with the above-mentioned structure emits light from the organic electroluminescent unit 3 by the applied power supplies.
- the conventional OLED has a problem in that when light emitted from the organic electroluminescent unit 3 goes out, light loss is caused by total reflection occurring inside of the glass substrate.
- light emitted from the organic electroluminescent unit 3 is incident into the glass substrate 1, and then goes out through a front exit surface Ia of the glass substrate 1.
- some light beams of light transmitted through the glass substrate 1 travel at an angle greater than the critical angle of the glass substrate 1, they fail to exit through the front exit surface Ia of the glass substrate 1, and are reflected inside of the glass substrate 1.
- the reflected light beams travel laterally while being re- reflected at an incident surface Ib 1 and finally are emitted to the outside, which results in light loss.
- an object of the present invention is to provide a surface treatment material for a glass substrate, which minimizes the amount of light totally reflected inside of a glass substrate of an OLED by reacting with a component constituting the glass substrate to form fine projections or grooves on a surface of the glass substrate, thereby making it possible to emit a large amount of light through an exit surface and thus provide light of high luminance, a surface treatment film coated with the surface treatment material, and an OLED with the surface treatment film attached thereto.
- a surface treatment material for a glass substrate including: an adhesive component for providing an adhesive force; and a surface treatment component, mixed with the adhesive component, for reacting with a component of the glass substrate to form a large number of projections or grooves functioning as fine lenses on a surface of the glass substrate.
- a surface treatment film for a glass substrate at least one side of which is coated with the above surface treatment material.
- an organic light emitting diode including: a glass substrate containing silicon (Si) as a main component; a transparent anode electrode formed on a backside of the glass substrate; an organic electroluminescent unit formed by depositing an organic material on a backside of the anode electrode; a cathode electrode formed on a backside of the organic electroluminescent unit; and a surface treatment film coated on at least one side thereof with a surface treatment film and adhered to a light exit surface of the glass substrate, the surface treatment material including an adhesive component for providing an adhesive force, and a surface treatment component, mixed with the adhesive component, for reacting with a silicate component of the glass substrate to form a large number of projections or grooves functioning as a fine lens on a surface of the glass substrate.
- Si silicon
- the adhesive component of the surface treatment material coated on the surface treatment film may include a UV- curable adhesive consisting of an acrylated polymer that can be cured by UV.
- the surface treatment component reacting with the silicon (Si) component of the glass substrate preferably includes at least one selected from the group consisting of chloro group- containing chlorosilane (R 3 -Si-Cl) compounds, -OH group- containing polysiloxanol (R 3 -Si-OH, R 2 -Si-(OH) 2 , or R-Si-(OH) 3 ) compounds, alkoxy group-containing alkoxysilane compounds, Si compounds having a cyclo structure, polymethylsiloxane (PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (-ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds (epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds, silicone cop
- a surface treatment film is firmly adhere to the exit surface of a glass substrate of a display device, in particular, an OLED, and fine convex projections or concave grooves are formed on the exit surface of the glass substrate by a surface treatment material provided on the surface treatment film, total reflection inside of the glass substrate can be minimized, and thus light of high luminance can be provided owing to an increase in the amount of light exiting through the exit surface.
- the glass substrate when the surface of the glass substrate is treated with the surface treatment film attached thereto, the glass substrate can be prevented from being weakened in strength by a surface treatment (in particular, etching) because the strength of the glass substrate is reinforced by the surface treatment film, and additionally the surface of the glass substrate can be simply treated without the damage of the glass substrate.
- a surface treatment in particular, etching
- FIG. 1 is a sectional view illustrating an exemplary structure of an essential part of a conventional organic light emitting diode
- FIG. 2 is a sectional view illustrating a structure of an organic light emitting diode in accordance with a preferred embodiment of the present invention
- FIG. 3 is a partial enlarged view of portion A of FIG. 2;
- FIG. 4 is a view similar to FIG. 3, but illustrating etched grooves formed on a glass substrate surface of the organic light emitting diode
- FIG. 5 illustrates 150-times-magnified photographs of glass substrate surfaces of a conventional organic light emitting diode and the inventive organic light emitting diode with a surface treatment film attached thereto, and their surface roughness graphs
- FIG. 6 is a graph illustrating a comparison between light exit efficiencies of a conventional organic light emitting diode and the inventive organic light emitting diode with a surface treatment film attached thereto.
- FIG. 2 illustrates an organic light emitting diode with a surface treatment film attached thereto according to a preferred embodiment of the present invention.
- the organic light emitting diode of the present invention includes a glass substrate 10 with a surface treatment film 80 adhered to a front light exit surface thereof, an anode electrode 20 formed in a given pattern on one side of the glass substrate 10, an organic electroluminescent unit 30 that is formed by depositing a specific chromophore- containing organic material on the anode electrode 20 and emits light by a flow of applied current, a cathode electrode 40 formed on the organic electroluminescent unit 30, and a sealing cover 50 adhered to the glass substrate 10 in such a manner as to hermetically seal the anode electrode 20, the organic electroluminescent unit 30, and the cathode electrode 40.
- the glass substrate 10 is mainly made of silicon (Si) .
- the anode electrode 20 is a transparent electrode made of an ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) , and may be deposited using various deposition techniques, such as sputtering, vapor deposition, or the like, while a mask with a given pattern is placed on the glass substrate 10.
- ITO Indium Tin Oxide
- IZO Indium Zinc Oxide
- the organic electroluminescent unit 30 includes an electron injection layer, an electron transfer layer, an emitting layer, a hole transfer layer, and a hole injection layer, and a plurality of such organic electroluminescent units 30 are arranged at regular intervals on the anode electrode 20 to thereby constitute individual pixel regions respectively.
- the cathode electrode 40 is formed by depositing aluminum (Al), magnesium (Mg), etc. in the shape of a band on the organic electroluminescent unit 30.
- the sealing cover 50 is adhered to the glass substrate 10 by means of an adhesive 70, and is internally provided with a getter 60 for absorbing moisture.
- the surface treatment film 80 is seat on the glass substrate 10, and then is cured and adhered thereto.
- the adhered surface treatment film 80 undergoes an aging process during which it performs a surface treatment function, that is, a function of forming projections or grooves in the form of a fine lens on the light exit surface of the glass substrate 10, and a function of reinforcing the strength of the surface-treated glass substrate 10.
- the surface treatment film 80 is coated on its side facing the glass substrate 10 with a mixture of an adhesive component and a surface treatment component, that is, a surface treatment material of the present invention.
- a surface treatment component that is, a surface treatment material of the present invention.
- the surface treatment material coated on the surface treatment film 80 has a composition in which a UV curable adhesive containing an acrylated polymer, and a surface treatment agent containing organic silicon (Si) reacting with the silicon (Si) component of the glass substrate 10 are mixed with each other.
- this embodiment proposes the UV curable adhesive, capable of being cured by UV radiation, as the adhesive component of the surface treatment material, any other adhesives that are spontaneously cured at room temperature may be used as the adhesive component.
- the acrylated polymer constituting the adhesive or bonding agent includes a reactive oligomer, a reactive diluent, an additive, a photopolymerization initiator, and so forth.
- the reactive oligomer of the adhesive may consist of a modified acrylic oligomer (epoxy, polyester, urethane, etc.), and an acrylate-based monomer that may be used as the reactive diluent acts as a solvent for the additive and the initiator, and simultaneously has an effect on postreactive physical properties.
- a takifier, a filler, a thermosetting catalyst, a colorant, etc. may be selectively used as the additive according to applications .
- the photopolymerization initiator may be the effective wavelength region, that is, the visible light region from 300 to 500nm, and the kinds of the photopolymerization initiator may be a benzophenone series, alpha-naphthol, trimethylbenzoyl, diphenylsufoxide, and the like, each of which is prepared based on an available wavelength region and the required amount according to the specification of each manufacturer .
- a modified urethane-acrylate prepolymer or modified epoxy-acrylate prepolymer-based high molecular polymer with a glass transition temperature (Tg) of 10 to -40 ° C may be used as the UV curable adhesive, but the present invention is not particularly limited to this glass transition temperature (Tg) .
- the acrylate-based monomer that may be used as the reactive diluent includes typical (meth) acrylic acid, a butyl
- the surface treatment component of the surface treatment material may be prepared in such a manner as to include at least one organic silicon (Si) compound selected from the group consisting of chloro group-containing chlorosilane (R 3 -Si-Cl) compounds, -OH group-containing polysiloxanol (R 3 -Si-OH, R 2 ⁇ Si- (OH) 2r or R-Si-(OH) 3 ) compounds, alkoxy group-containing alkoxysilane compounds, Si compounds having a cyclo structure, polymethylsiloxane (PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (- ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds (epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds,
- triethoxysilane, trimethoxymethylsilane, trimethoxy (octyl) silane, trimethoxy (2-phenylethyl) silane, trimethoxyphenylsilane, trimethoxysilane, tris (2-methoxyethoxy) silane, vinyltrimethoxysilane may be selectively used for preparing the surface treatment component.
- the silicon (Si) compounds having the cyclo structure have the following molecular structure:
- vinyl group-containing silicon (Si) compounds have the following molecular structure:
- FIG. 3 illustrates projections 11 functioning as a fine microlens, which are formed on the surface of the glass substrate 10 by the surface treatment material of the surface treatment film 80.
- the projections 11 that are formed integrally with the glass substrate 10 without any interface by the surface treatment component of the surface treatment material 5 increase the surface roughness of the glass substrate 10, thereby remarkably reducing the possibility of total reflection of light incident into the glass substrate 10.
- the surface treatment material may increase the surface roughness by forming concave
- the surface treatment component of the surface treatment material may consist of a hydrochloric acid lfi (HCl) -based organic silicate compound.
- HCl hydrochloric acid lfi
- Such an organic silicate compound has the action of etching the glass surface with a constant and uniform height through a chemical etching method in which the glass surface is made hydrophilic by cleaning with an organic/inorganic cleaner, and then the organic silicate compound 0 is induced to react with organic silicon (Si) .
- the surface treatment film 80 may consist of a simple light-transmissive film.
- a lens film with a specific lens pattern formed on a surface thereof, a color filter film, a polarizer film, or an AR (Anti-Reflection) film may be 5 coated on its one side with the above-mentioned surface treatment material, so that a surface treatment function can be added to the use of each film.
- the surface treatment film 80 preferably has the same area as that of the glass substrate 10.
- the front light exit surface 11 of the glass substrate 10 is treated with the surface treatment material of the surface treatment film 80 in such a manner as to be rough.
- the surface treatment material of the surface treatment film 80 in such a manner as to be rough.
- FIG. 5 illustrates 150-times-magnified photographs of glass substrate surfaces of a conventional OLED and the inventive OLED with a surface treatment film 80 attached thereto, and their surface roughness graphs.
- FIG. 6 graphically illustrates a comparison between light exit efficiencies of the conventional OLED and the inventive OLED with the surface treatment film 80 attached thereto.
- the glass substrate of the conventional OLED is provided with a very smooth surface, and exhibits relatively low light exit efficiency. This is because the light exit surface of the conventional glass substrate forms a smooth mirror surface, which leads to the lowering of light exit efficiency due to an increase in internal total reflection.
- the inventive glass substrate 10 with the surface treatment film 80 attached thereto are formed with a large number of random-shaped projections or grooves for increasing surface roughness, and thus has relatively improved light exit efficiency.
- the surface treatment film 80 of the present invention is firmly adhered to one side of the glass substrate 10 to thereby provide an additional advantage of reinforcing the strength of the glass substrate 10, the strength of the glass substrate 10 is significantly increased as compare to a simple surface treatment in which the surface of the glass substrate 10 is impregnated or sprayed with a surface treatment solution.
- the glass substrate 10 is surface-treated by adhering the surface treatment film 80 coated with the surface treatment material of the present invention to the surface of the glass substrate 10 in the OLED according to the aforementioned embodiment of the present invention, it is alternatively possible to surface-treat the glass substrate 10 only by coating the surface of the glass substrate 10 with the surface treatment material of the present invention without adhering the surface treatment film thereto.
- the process of coating the surface of the glass substrate 10 with the surface treatment material may be followed by a process of uniformly cutting the coated surface.
- the present invention is applicable to all products employing a silicon (Si) -containing glass substrate, and particularly can be advantageously applied to a display device, such as an OLED.
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Abstract
Disclosed are a surface treatment material for surface-treating a glass substrate of a display device, such as an OLED, by attaching to a surface of the glass substrate and reacting with a component of the glass substrate to form fine projections or grooves on the surface, a surface treatment film coated with such a surface treatment material, and an OLED that minimizes loss of light emitted through a glass substrate by means of such a surface treatment film adhered to the glass substrate, and thereby can provide light of high luminance. The surface treatment film is coated on at least one side with the surface treatment material including an adhesive component for providing an adhesive force, and a surface treatment component, mixed with the adhesive component, for reacting with a component of the glass substrate to form a large number of projections or grooves functioning as fine lenses on the surface of the glass substrate.
Description
[DESCRIPTION]
[invention Title]
SURFACE TREATMENT MATERIAL, A FILM COATED WITH THE SURFACE TREATMENT MATERIAL, AND AN ORGANIC LIGHT EMITTING DIODE HAVING THE FILM
[Technical Field]
The present invention relates to a surface treatment material for reacting with a glass substrate of a display device, a surface treatment film coated with such a surface treatment material, and an organic light emitting diode with such a surface treatment film. More particularly, the present invention relates to a surface treatment material for attaching to a surface of a glass substrate of a display device, such as an organic light emitting display (OLED) , and reacting with a component of the glass substrate to form fine projections or grooves on the surface, a surface treatment film, one side of which is coated with such a surface treatment material for a glass substrate, and an OLED that minimizes loss of light emitted through a glass substrate by means of such a surface treatment film adhered to the glass substrate, and thereby can provide light of high luminance .
[Background Art] As generally known in the art, an OLED is a self- luminescent display device using a phenomenon that electrons and holes injected from negative and positive electrodes are recombined with each other in an organic film to generate
excitons, and energy from the excitons leads to emission of light of a specific wavelength.
This OLED has advantages in that it requires no additional surface light source, such as a backlight unit, because of its self-luminescence, and have a wide viewing angle, a high response speed, and a small thickness.
FIG. 1 illustrates the structure of a typical OLED. The typical OLED is fabricated by depositing an ITO metal in a given pattern on a glass substrate 1 to form an anode electrode 2 to which a positive power supply is applied, depositing a specific chromophore-containing organic material on the anode electrode 2 to form an organic electroluminescent unit 3 that emits light by a flow of current, and then depositing a cathode-forming material, that is, an electrode material, such as aluminum (Al) , magnesium (Mg) and so forth, on an upper surface of the organic electroluminescent unit 3 to form a cathode electrode 4.
When the organic material forming the organic electroluminescent unit 3 comes into contact with moisture or oxygen in air, its performance and lifetime significantly deteriorate. Thus, after the anode electrode, the electroluminescent unit 3, and the cathode electrode 4 are deposited in sequence on the glass substrate 1, a sealing cover 5 with a built-in getter 6 is adhered to one side of the glass substrate 1 by means of an adhesive 7 in such a manner as to hermetically seal the side on which the organic material is formed. In this way, the OLED is completed.
If power supplies are applied to the cathode electrode 4 and the anode electrode 2, the OLED with the above-mentioned
structure emits light from the organic electroluminescent unit 3 by the applied power supplies.
However, the conventional OLED has a problem in that when light emitted from the organic electroluminescent unit 3 goes out, light loss is caused by total reflection occurring inside of the glass substrate.
More specially, light emitted from the organic electroluminescent unit 3 is incident into the glass substrate 1, and then goes out through a front exit surface Ia of the glass substrate 1. However, since some light beams of light transmitted through the glass substrate 1 travel at an angle greater than the critical angle of the glass substrate 1, they fail to exit through the front exit surface Ia of the glass substrate 1, and are reflected inside of the glass substrate 1. The reflected light beams travel laterally while being re- reflected at an incident surface Ib1 and finally are emitted to the outside, which results in light loss.
[Disclosure] [Technical Problem]
Accordingly, the present invention has been made to solve the above-mentioned problems occurring in the prior art, and an object of the present invention is to provide a surface treatment material for a glass substrate, which minimizes the amount of light totally reflected inside of a glass substrate of an OLED by reacting with a component constituting the glass substrate to form fine projections or grooves on a surface of the glass substrate, thereby making it possible to emit a large amount of
light through an exit surface and thus provide light of high luminance, a surface treatment film coated with the surface treatment material, and an OLED with the surface treatment film attached thereto.
[Technical Solution]
In accordance with an aspect of the present invention, there is provided a surface treatment material for a glass substrate, the surface treatment material including: an adhesive component for providing an adhesive force; and a surface treatment component, mixed with the adhesive component, for reacting with a component of the glass substrate to form a large number of projections or grooves functioning as fine lenses on a surface of the glass substrate. In accordance with another aspect of the present invention, there is provided a surface treatment film for a glass substrate, at least one side of which is coated with the above surface treatment material.
In accordance with yet another aspect of the present invention, there is provided an organic light emitting diode including: a glass substrate containing silicon (Si) as a main component; a transparent anode electrode formed on a backside of the glass substrate; an organic electroluminescent unit formed by depositing an organic material on a backside of the anode electrode; a cathode electrode formed on a backside of the organic electroluminescent unit; and a surface treatment film coated on at least one side thereof with a surface treatment film and adhered to a light exit surface of the glass substrate, the
surface treatment material including an adhesive component for providing an adhesive force, and a surface treatment component, mixed with the adhesive component, for reacting with a silicate component of the glass substrate to form a large number of projections or grooves functioning as a fine lens on a surface of the glass substrate.
Preferably, the adhesive component of the surface treatment material coated on the surface treatment film may include a UV- curable adhesive consisting of an acrylated polymer that can be cured by UV.
Also, the surface treatment component reacting with the silicon (Si) component of the glass substrate preferably includes at least one selected from the group consisting of chloro group- containing chlorosilane (R3-Si-Cl) compounds, -OH group- containing polysiloxanol (R3-Si-OH, R2-Si-(OH)2, or R-Si-(OH)3) compounds, alkoxy group-containing alkoxysilane compounds, Si compounds having a cyclo structure, polymethylsiloxane (PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (-ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds (epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds, silicone copolymers, polycarbosilane compounds, polysilanzane compounds, polysiloxane compounds, silyl compounds, and siloxy compounds.
[Advantageous Effects]
According to the present invention, since a surface treatment film is firmly adhere to the exit surface of a glass substrate of a display device, in particular, an OLED, and fine convex projections or concave grooves are formed on the exit surface of the glass substrate by a surface treatment material provided on the surface treatment film, total reflection inside of the glass substrate can be minimized, and thus light of high luminance can be provided owing to an increase in the amount of light exiting through the exit surface. Further, when the surface of the glass substrate is treated with the surface treatment film attached thereto, the glass substrate can be prevented from being weakened in strength by a surface treatment (in particular, etching) because the strength of the glass substrate is reinforced by the surface treatment film, and additionally the surface of the glass substrate can be simply treated without the damage of the glass substrate.
[Brief Description of the Drawings]
The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings, in which:
FIG. 1 is a sectional view illustrating an exemplary structure of an essential part of a conventional organic light emitting diode;
FIG. 2 is a sectional view illustrating a structure of an organic light emitting diode in accordance with a preferred embodiment of the present invention;
FIG. 3 is a partial enlarged view of portion A of FIG. 2;
FIG. 4 is a view similar to FIG. 3, but illustrating etched grooves formed on a glass substrate surface of the organic light emitting diode; FIG. 5 illustrates 150-times-magnified photographs of glass substrate surfaces of a conventional organic light emitting diode and the inventive organic light emitting diode with a surface treatment film attached thereto, and their surface roughness graphs; and FIG. 6 is a graph illustrating a comparison between light exit efficiencies of a conventional organic light emitting diode and the inventive organic light emitting diode with a surface treatment film attached thereto.
[Best Mode]
Hereinafter, preferred embodiments of a surface treatment material for a glass substrate, a surface treatment film coated with such a surface treatment material, and an organic light emitting diode with such a surface treatment film according to the present invention will be described with reference to the accompanying drawings .
FIG. 2 illustrates an organic light emitting diode with a surface treatment film attached thereto according to a preferred embodiment of the present invention. The organic light emitting diode of the present invention includes a glass substrate 10 with a surface treatment film 80 adhered to a front light exit surface thereof, an anode electrode 20 formed in a given pattern on one side of the glass substrate 10, an organic electroluminescent
unit 30 that is formed by depositing a specific chromophore- containing organic material on the anode electrode 20 and emits light by a flow of applied current, a cathode electrode 40 formed on the organic electroluminescent unit 30, and a sealing cover 50 adhered to the glass substrate 10 in such a manner as to hermetically seal the anode electrode 20, the organic electroluminescent unit 30, and the cathode electrode 40.
The glass substrate 10 is mainly made of silicon (Si) .
The anode electrode 20 is a transparent electrode made of an ITO (Indium Tin Oxide) or IZO (Indium Zinc Oxide) , and may be deposited using various deposition techniques, such as sputtering, vapor deposition, or the like, while a mask with a given pattern is placed on the glass substrate 10.
The organic electroluminescent unit 30 includes an electron injection layer, an electron transfer layer, an emitting layer, a hole transfer layer, and a hole injection layer, and a plurality of such organic electroluminescent units 30 are arranged at regular intervals on the anode electrode 20 to thereby constitute individual pixel regions respectively. The cathode electrode 40 is formed by depositing aluminum (Al), magnesium (Mg), etc. in the shape of a band on the organic electroluminescent unit 30.
The sealing cover 50 is adhered to the glass substrate 10 by means of an adhesive 70, and is internally provided with a getter 60 for absorbing moisture.
The surface treatment film 80 is seat on the glass substrate 10, and then is cured and adhered thereto. The adhered surface treatment film 80 undergoes an aging process during which
it performs a surface treatment function, that is, a function of forming projections or grooves in the form of a fine lens on the light exit surface of the glass substrate 10, and a function of reinforcing the strength of the surface-treated glass substrate 10.
In order to these functions, the surface treatment film 80 is coated on its side facing the glass substrate 10 with a mixture of an adhesive component and a surface treatment component, that is, a surface treatment material of the present invention. Thus, when the surface treatment film 80 is seated on the glass substrate 10, it is adhered to the glass substrate 10 by the adhesive component, and in this state, the surface treatment component of the surface treatment film 80 reacts with the surface of the glass substrate 10 to form convex lens-like projections or concave etched grooves, as a result of which the surface of the glass substrate 10 becomes rough.
More specially, the surface treatment material coated on the surface treatment film 80 has a composition in which a UV curable adhesive containing an acrylated polymer, and a surface treatment agent containing organic silicon (Si) reacting with the silicon (Si) component of the glass substrate 10 are mixed with each other.
Although this embodiment proposes the UV curable adhesive, capable of being cured by UV radiation, as the adhesive component of the surface treatment material, any other adhesives that are spontaneously cured at room temperature may be used as the adhesive component.
The acrylated polymer constituting the adhesive or bonding
agent includes a reactive oligomer, a reactive diluent, an additive, a photopolymerization initiator, and so forth.
The reactive oligomer of the adhesive may consist of a modified acrylic oligomer (epoxy, polyester, urethane, etc.), and an acrylate-based monomer that may be used as the reactive diluent acts as a solvent for the additive and the initiator, and simultaneously has an effect on postreactive physical properties. Also, a takifier, a filler, a thermosetting catalyst, a colorant, etc. may be selectively used as the additive according to applications .
Further, the photopolymerization initiator may be the effective wavelength region, that is, the visible light region from 300 to 500nm, and the kinds of the photopolymerization initiator may be a benzophenone series, alpha-naphthol, trimethylbenzoyl, diphenylsufoxide, and the like, each of which is prepared based on an available wavelength region and the required amount according to the specification of each manufacturer .
As an example, a modified urethane-acrylate prepolymer or modified epoxy-acrylate prepolymer-based high molecular polymer with a glass transition temperature (Tg) of 10 to -40 °C may be used as the UV curable adhesive, but the present invention is not particularly limited to this glass transition temperature (Tg) .
Further, the acrylate-based monomer that may be used as the reactive diluent includes typical (meth) acrylic acid, a butyl
(meth) acrylate system, an ethyl (meth) acrylate system,
(methyl)methacrylate, 2-ethylhexyl acrylate, glycidyl methacrylate, lauryl methacrylate, dimethylaminoethyl
methacrylate, cyanoacrylate, and so forth. In addition to such an acrylate-based monomer, all (meth) acrylate-based materials that have a vinyl group double bond may be used as the reactive diluent . The surface treatment component of the surface treatment material may be prepared in such a manner as to include at least one organic silicon (Si) compound selected from the group consisting of chloro group-containing chlorosilane (R3-Si-Cl) compounds, -OH group-containing polysiloxanol (R3-Si-OH, R2~Si- (OH) 2r or R-Si-(OH)3) compounds, alkoxy group-containing alkoxysilane compounds, Si compounds having a cyclo structure, polymethylsiloxane (PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (- ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds (epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds, silicone copolymers, polycarbosilane compounds, polysilanzane compounds, polysiloxane compounds, silyl compounds, and siloxy compounds. For example, triethoxysilane, trimethoxymethylsilane, trimethoxy (octyl) silane, trimethoxy (2-phenylethyl) silane, trimethoxyphenylsilane, trimethoxysilane, tris (2-methoxyethoxy) silane, vinyltrimethoxysilane may be selectively used for preparing the surface treatment component.
From among the organic silicon compounds, the silicon (Si) compounds having the cyclo structure have the following molecular structure:
Also, the vinyl group-containing silicon (Si) compounds have the following molecular structure:
HC—CH2
Compounds that may be used as the surface treatment component of the surface treatment material according to the present invention are listed in Table 1.
Table 1
-SiMe2- (CH2) 3-COOH
-SiMe2- (CH2) 3-NH2
-SiMe2- (CH2) 3-NH-CH3
-SiMe2- (CH2) 3-OH
-SiMe2- (CH2) 4 -OH
-SiMe2- (CH2) 3-0-CH2-CH-CH2O
-SiMe2- (CH2) 3 -0-CH2 -CHOH-CH2OH
-SiMe2- (CH2) 2!-C6H4CH2Cl
-SiMe2- (CH2) 2-C6H5→-SiMe2- (CH2) 2-C6H4-CH2Cl
-SiMe2- (CH2) 3-C6H5-OH
-SiMe2-R
-SiMe2- (CH2) 10-C-R
-SiMe2- (CH2) 3-C6H4-CHO
-SiMe2- (CH2) 4-CH=CH2→-SiMe2- (CH2J4-CHO
Cl-PDMS-Cl (PDMS-PC)n
HOCO-DMS-OOH (PDMS-PC)n
H2N-PDMS-H2 (PDMS-PE)n
H2N-PDMS-H2 (PDMS-PE)n
H2N-PDMS-H2 (PDMS-PA)n
H2N-PDMS-H2 (PDMS-polyurea)n
H2N-PDMS-H2 (PDMS-PI)n
Anhydride-PDMS-anhydride (PDMS-PI)n
HO-DMS-H (PDMS-PU)n
Cl-PDMS-Cl (PDMS-UPE)n
Cl-PDMS-Cl (PDMS-PE)n
Me2N-PDMS-NMe2 (PDMS-PSU)n
Me2N-PDMS-NMe2 (PDMS-PC)n
Me2N-PDMS-NMe2 (PDMS-PE)n
Me2N-PDMS-NMe2 (PDMS-PaMS)n
Me2N-PDMS-NMe2 (PDMS-PPO)n
HOCO-DMS-OOH (PDMS-PA)n
H2N-PDMS-H2 (PDMS-PA)n
H2N-PDMS-H2 (PDMS-PU)n
H2N-PDMS-H2 (PDMS-polyurea)n
H2N-PDMS-H2 (PDMS-polyimide) n
R-PDMS-R (PDMS-UPE)n
R-PDMS-R (PDMS-PSU)n
R-PDMS-R (PDMS-PSU)n
Anhydride-PDMS-anhydride (PDMS-PEEK)n
OHC-Ph-PDMS-Ph-CHO (PDMS-Pa)n
H-PDMS-H (PDMS-polyethylene) n
H-PDMS-H (PDMS-PSU)n
(PDMS-PS)n
(PDMS-PMS)n
(PDMS-PSU)n
(PDMS-POE)n
(PDMS-PLLA)n
(PDMS-iPP)n
FIG. 3 illustrates projections 11 functioning as a fine microlens, which are formed on the surface of the glass substrate
10 by the surface treatment material of the surface treatment film 80. In this way, the projections 11 that are formed integrally with the glass substrate 10 without any interface by the surface treatment component of the surface treatment material 5 increase the surface roughness of the glass substrate 10, thereby remarkably reducing the possibility of total reflection of light incident into the glass substrate 10.
Also, as illustrated in FIG. 4, the surface treatment material may increase the surface roughness by forming concave
10 grooves 12 on the surface of the glass surface 10, rather than the projections.
When the surface treatment material is intended to act as an echant in this way, the surface treatment component of the surface treatment material may consist of a hydrochloric acid lfi (HCl) -based organic silicate compound. Such an organic silicate compound has the action of etching the glass surface with a constant and uniform height through a chemical etching method in which the glass surface is made hydrophilic by cleaning with an organic/inorganic cleaner, and then the organic silicate compound 0 is induced to react with organic silicon (Si) .
The surface treatment film 80 may consist of a simple light-transmissive film. Alternatively, a lens film with a specific lens pattern formed on a surface thereof, a color filter film, a polarizer film, or an AR (Anti-Reflection) film may be 5 coated on its one side with the above-mentioned surface treatment material, so that a surface treatment function can be added to the use of each film.
Further, the surface treatment film 80 preferably has the
same area as that of the glass substrate 10.
As mentioned above, in the organic light emitting diode of the present invention, the front light exit surface 11 of the glass substrate 10 is treated with the surface treatment material of the surface treatment film 80 in such a manner as to be rough. Thus, as illustrated in the drawings, when light emitted from the organic electroluminescent unit 30 in each pixel region is incident into the glass substrate 10, and then strikes the exit surface, a large amount of light beams that have traveled at an angel greater than the critical angle can goes out through the exit surface without suffering from total reflection by the projections 11 or grooves 12 on the surface.
FIG. 5 illustrates 150-times-magnified photographs of glass substrate surfaces of a conventional OLED and the inventive OLED with a surface treatment film 80 attached thereto, and their surface roughness graphs. Also, FIG. 6 graphically illustrates a comparison between light exit efficiencies of the conventional OLED and the inventive OLED with the surface treatment film 80 attached thereto. As seen from FIGS. 5 and 6, the glass substrate of the conventional OLED is provided with a very smooth surface, and exhibits relatively low light exit efficiency. This is because the light exit surface of the conventional glass substrate forms a smooth mirror surface, which leads to the lowering of light exit efficiency due to an increase in internal total reflection.
However, the inventive glass substrate 10 with the surface treatment film 80 attached thereto are formed with a large number of random-shaped projections or grooves for increasing surface
roughness, and thus has relatively improved light exit efficiency.
Also, since the surface treatment film 80 of the present invention is firmly adhered to one side of the glass substrate 10 to thereby provide an additional advantage of reinforcing the strength of the glass substrate 10, the strength of the glass substrate 10 is significantly increased as compare to a simple surface treatment in which the surface of the glass substrate 10 is impregnated or sprayed with a surface treatment solution. In addition, although the glass substrate 10 is surface- treated by adhering the surface treatment film 80 coated with the surface treatment material of the present invention to the surface of the glass substrate 10 in the OLED according to the aforementioned embodiment of the present invention, it is alternatively possible to surface-treat the glass substrate 10 only by coating the surface of the glass substrate 10 with the surface treatment material of the present invention without adhering the surface treatment film thereto. Of course, the process of coating the surface of the glass substrate 10 with the surface treatment material may be followed by a process of uniformly cutting the coated surface.
[industrial Applicability]
The present invention is applicable to all products employing a silicon (Si) -containing glass substrate, and particularly can be advantageously applied to a display device, such as an OLED.
Claims
[CLAIMS] [Claim 1]
A surface treatment material for a glass substrate, the surface treatment material comprising: an adhesive component for providing an adhesive force; and a surface treatment component, mixed with the adhesive component, for reacting with a silicon (Si) component of the glass substrate to form a large number of projections or grooves functioning as fine lenses on a surface of the glass substrate.
[Claim 2]
The surface treatment material as claimed in claim 1, wherein the adhesive component of the surface treatment material comprises a UV-curable adhesive that consists of an acrylated polymer capable of being cured by UV.
[Claim 3]
The surface treatment material as claimed in claim 1, wherein the surface treatment component of the surface treatment material comprises a silicon (Si) compound reacting with a silicon (Si) compound of the glass substrate.
[Claim 4]
The surface treatment material as claimed in claim 3, wherein the surface treatment component is prepared using at least one selected from the group consisting of chloro group- containing chlorosilane (R3-Si-Cl) compounds, -OH group- containing polysiloxanol (R3-Si-OH, R2-Si-(OH)2, or R-Si-(OH)3)
compounds, alkoxy group-containing alkoxysilane compounds, Si compounds having a cyclo structure, polymethylsiloxane
(PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (-ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds
(epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds, silicone copolymers, polycarbosilane compounds, polysilanzane compounds, polysiloxane compounds, silyl compounds, and siloxy compounds.
[Claim 5]
A surface treatment film for a glass substrate, at least one side of which is coated with the surface treatment material as claimed in claim 1 and which is securely adhered to a surface of the glass substrate.
[Claim β] The surface treatment film as claimed in claim 5, wherein the adhesive component of the surface treatment material comprises a UV-curable adhesive that consists of an acrylated polymer capable of being cured by UV.
[Claim 7]
The surface treatment film as claimed in claim 5, wherein the surface treatment component of the surface treatment material comprises a silicon (Si) compound reacting with a silicon (Si)
compound of the glass substrate.
[Claim 8]
The surface treatment film as claimed in claim 7, wherein the surface treatment component is prepared using at least one selected from the group consisting of chloro group-containing chlorosilane (R3-Si-Cl) compounds, -OH group-containing polysiloxanol (R3-Si-OH, R2-Si-(OH)2, or R-Si-(OH)3) compounds, alkoxy group-containing alkoxysilarie compounds, Si compounds having a cyclo structure, polymethylsiloxane (PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (-ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds (epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds, silicone copolymers, polycarbosilane compounds, polysilanzane compounds, polysiloxane compounds, silyl compounds, and siloxy compounds.
[Claim 9]
The surface treatment film as claimed in claim 5, wherein the surface treatment film comprises any one selected from the group consisting of a lens film with a specific lens pattern formed on a surface thereof, a color filter film, a polarizer film, and an anti-reflection (AR) film.
[Claim 10]
An organic light emitting diode comprising: a glass substrate containing silicon (Si) as a main component; a transparent anode electrode formed on a backside of the glass substrate; an organic electroluminescent unit formed by depositing an organic material on a backside of the anode electrode; a cathode electrode formed on a backside of the organic electroluminescent unit; and a surface treatment film as claimed in claim 5, which is adhered to a light exit surface of the glass substrate.
[Claim 11]
The organic light emitting diode as claimed in claim 10, wherein the adhesive component of the surface treatment material comprises a UV-curable adhesive that consists of an acrylated polymer capable of being cured by UV.
[Claim 12] The organic light emitting diode as claimed in claim 10, wherein the surface treatment component of the surface treatment material comprises a silicon (Si) compound reacting with a silicon (Si) compound of the glass substrate.
[Claim 13]
The organic light emitting diode as claimed in claim 12, wherein the surface treatment component is prepared using at least one selected from the group consisting of chloro group-
containing chlorosilane (R3-Si-Cl) compounds, -OH group- containing polysiloxanol (R3-Si-OH, R2-Si-(OH)2, or R-Si-(OH)3) compounds, alkoxy group-containing alkoxysilane compounds, Si compounds having a cyclo structure, polymethylsiloxane (PMS) /polydimethylsiloxane (PDMS) -containing Si compounds, disiloxane-containing compounds, alcohol group (-ROH) -containing Si compounds, Si compounds containing a hydrogen group as a functional group (-Si-H) , vinyl group-containing Si compounds, chemical reactive functional group-containing Si compounds (epoxy-, urethane-, acrylic-) , colloidal silicate compounds, silica sol compounds, silicone copolymers, polycarbosilane compounds, polysilanzane compounds, polysiloxane compounds, silyl compounds, and siloxy compounds.
[Claim 14]
The organic light emitting diode as claimed in claim 10, wherein the surface treatment film comprises any one selected from the group consisting of a lens film with a specific lens pattern formed on a surface thereof, a color filter film, a polarizer film, and an anti-reflection (AR) film.
Applications Claiming Priority (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR20070088518 | 2007-08-31 | ||
| KR10-2007-0088518 | 2007-08-31 | ||
| KR10-2007-0108900 | 2007-10-29 | ||
| KR1020070108900A KR100919281B1 (en) | 2007-08-31 | 2007-10-29 | surface treatment, film coated with the surface treatment, and Organic Light Emitting Diode having the film |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2009028762A1 true WO2009028762A1 (en) | 2009-03-05 |
Family
ID=40387454
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/KR2007/005558 WO2009028762A1 (en) | 2007-08-31 | 2007-11-05 | Surface treatment material, a film coated with the surface treatment material, and an organic light emitting diode having the film |
Country Status (2)
| Country | Link |
|---|---|
| KR (1) | KR100919281B1 (en) |
| WO (1) | WO2009028762A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR101760849B1 (en) | 2011-03-04 | 2017-07-25 | 삼성디스플레이 주식회사 | Liquid crystal display |
| KR101658903B1 (en) * | 2012-03-23 | 2016-09-23 | 주식회사 엘지화학 | Substrate for organic electronic device |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05319869A (en) * | 1992-05-25 | 1993-12-03 | Nissan Motor Co Ltd | Sol-gel film and its formation |
| JPH06157076A (en) * | 1992-11-13 | 1994-06-03 | Central Glass Co Ltd | Low reflecting glass and its production |
| JP2004292194A (en) * | 2003-03-26 | 2004-10-21 | Mitsuboshi Belting Ltd | Method for manufacturing glass plate having low reflective film, and glass plate having low reflective film |
| JP2006269328A (en) * | 2005-03-25 | 2006-10-05 | Seiko Epson Corp | Light emitting device |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7122958B2 (en) * | 2003-05-16 | 2006-10-17 | Kabushiki Kaisha Toyota Jidoshokki | Light-emitting apparatus and method for forming the same |
-
2007
- 2007-10-29 KR KR1020070108900A patent/KR100919281B1/en not_active IP Right Cessation
- 2007-11-05 WO PCT/KR2007/005558 patent/WO2009028762A1/en active Application Filing
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH05319869A (en) * | 1992-05-25 | 1993-12-03 | Nissan Motor Co Ltd | Sol-gel film and its formation |
| JPH06157076A (en) * | 1992-11-13 | 1994-06-03 | Central Glass Co Ltd | Low reflecting glass and its production |
| JP2004292194A (en) * | 2003-03-26 | 2004-10-21 | Mitsuboshi Belting Ltd | Method for manufacturing glass plate having low reflective film, and glass plate having low reflective film |
| JP2006269328A (en) * | 2005-03-25 | 2006-10-05 | Seiko Epson Corp | Light emitting device |
Also Published As
| Publication number | Publication date |
|---|---|
| KR100919281B1 (en) | 2009-09-30 |
| KR20090022990A (en) | 2009-03-04 |
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