KR100592279B1 - Screen printing methode, manufacturing methode of organic light emitting display device, and organic light emitting display device - Google Patents

Abstract

According to an aspect of the present invention, there is provided a screen printing method for uniformly applying a desiccant to a sealing substrate having an inlet, wherein the screen mask member is printed by printing a mixture in a predetermined pattern. And a support member having a screen mask having a screen portion to be formed in contact with the screen mask and having an opening provided in an area larger than an area of the screen portion, wherein the screen mask member is disposed so that the support member faces the substrate. A screen printing method, a method of manufacturing an organic light emitting display device using the same, and manufacturing the same, by pressing a squeeze on the screen mask and printing the mixture on the screen mask to form a mixture pattern corresponding to the screen part. An organic electroluminescent display is provided.

Description

Screen printing method, manufacturing method of organic electroluminescent display, and organic electroluminescent display device {Screen printing methode, manufacturing method of organic light emitting display device, and organic light emitting display device}

1 and 2 are cross-sectional views showing a state in which a desiccant is applied by a screen printing method to a sealing substrate on which an inlet is formed;

3 is a cross-sectional view showing a screen printing method according to an embodiment of the present invention;

4 is a cross-sectional view showing a state in which a desiccant is applied by a screen printing method to a sealing substrate on which an inlet is formed according to an exemplary embodiment of the present invention;

5 and 6 are cross-sectional views illustrating different embodiments of a flat panel display device according to the present invention.

<Brief description of the main parts of the drawing>

40: screen mask member 41: screen mask

42: screen portion 43: support member

44: opening 45: squeeze

50: sealing substrate 51: inlet

51a: flat part 51b: side wall part

52: desiccant 53: sealant

60: substrate 61: display portion

The present invention relates to a screen printing method, a method of manufacturing an organic light emitting display device, and an organic light emitting display device, and more particularly, a screen printing method capable of precise printing, a method of manufacturing an organic light emitting display device using the same, and organic The present invention relates to an electroluminescent display.

In general, the organic light emitting display device is ultra-thin and flexible due to its driving characteristics, and many studies have been conducted.

However, such an organic light emitting display device is deteriorated by the penetration of moisture. Therefore, a sealing structure is needed to prevent the penetration of moisture.

Conventionally, metal cans or glass substrates are processed into caps so as to have grooves to form sealing members, and in the grooves, desiccants for absorption of moisture are mounted in powder form or in the form of films. After manufacturing and adhering with a double-sided tape, a method of joining the sealing member to a substrate on which an element was formed using a UV curing sealant or a thermosetting sealant was used.

In this manner, there is a method disclosed in US Pat. No. 5,882,761, which is a laminate having a structure in which an organic light emitting material layer of an organic compound is placed between a pair of electrodes facing each other, An organic electroluminescent display device having an airtight container for blocking and a drying means disposed in the airtight container, wherein the drying means adsorbs water and retains a solid state even when adsorbed thereon. Alkali metal oxides, sulfates, etc. are proposed as a drying means.

In the case of the organic light emitting display device employing such a method, as shown in FIGS. 1 and 2, the sealing substrate 10 of glass material in which the inlet portion 11 having a predetermined depth is etched on the surface thereof. Use

The lead portion 11 is provided with a flat portion 11a and a side wall portion 11b. The side wall portion 11b is inclined at a predetermined angle with respect to the flat portion 11a. A desiccant 12 is applied to the lead portion 11.

By the way, in the case of the desiccant applied to the inlet portion 11 is applied by the screen printing method, there is a problem that the application area of the desiccant 12 is uneven in the conventional screen printing method.

As can be seen in FIGS. 1 and 2, the screen mask member 30 used in the screen printing method includes a screen mask 31 having a screen portion 22 on which a desiccant can be printed, and a support having an opening 24. It is provided with the member 33.

However, as shown in FIG. 1, the ends 22a and 24a are inward from the edge of the inlet 11 in a state where the end 22a of the screen portion 22 and the end 24a of the opening portion 24 are coincident with each other. In the case that the support member 23 is supported by the screen portion 22, the phenomenon occurs that the printing is not properly performed even on the flat portion 11a of the inlet portion 11.

And, as shown in Fig. 2, the ends 22a and 24a of the screen portion 22 and the ends 24a of the opening 24 coincide with the edges of the inlet portion 11. Even in the case of alignment, the support member 23 is supported by the screen portion 22, so that not only the side wall portion 11b of the inlet portion 11 but also the flat portion 11a may not print properly. do.

In this case, when the desiccant 12 is not properly applied to the inlet 11, the portion of the desiccant 12 and the non-coated portion of the front emission type structure in which an image is realized in the direction of the sealing substrate 10 is implemented. There is a problem that the visibility of the screen is poor due to the step difference.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and includes a screen printing method capable of uniformly applying a desiccant to a sealing substrate having an inlet, a method of manufacturing an organic electroluminescent display, and an organic electroluminescent display manufactured therefrom The object is to provide a device.

In order to achieve the above object, the present invention,

In the screen printing method of screen printing a mixture on a substrate using a screen mask member,

The screen mask member,

A screen mask having a screen portion on which a mixture is printed in a predetermined pattern; And

And a support member in contact with the screen mask, the support member having an opening having a width larger than that of the screen portion.

Screen printing, characterized in that to form a mixture pattern corresponding to the screen portion by pressing a squeeze on the mixture on the screen mask in the state in which the screen mask member is disposed so that the support member faces the substrate. Provide a method.

An end portion of the screen portion may be spaced apart from an end portion of the opening portion by a predetermined distance toward the center of the opening portion.

When the end of the screen portion is a distance from the end of the opening is referred to as L, and the thickness of the support member T, the L and T may satisfy L> = T.

The substrate may include a predetermined inlet, and the screen may correspond to the inlet.

In order to achieve the above object, the present invention provides a method of manufacturing an organic electroluminescent display device which screen-prints a desiccant with a screen mask member on a sealing substrate having an inlet.

The screen mask member,

A screen mask having a screen portion on which the desiccant is printed; And

And a support member in contact with the screen mask, the support member having an opening having a width larger than that of the screen portion.

In a state where the screen mask member is disposed so that the support part faces the sealing substrate, the desiccant placed on the screen mask is pressurized with a squeeze to form a desiccant pattern corresponding to the screen part. A method of manufacturing an organic light emitting display device is provided.

An end portion of the screen portion may be spaced apart from an end portion of the opening portion by a predetermined distance toward the center of the opening portion.

When the distance between the end of the screen portion and the end of the opening is referred to as L and the thickness of the support member as T, L and T may satisfy L> = T.

The substrate may include a predetermined inlet, and the screen unit may correspond to the inlet.

In order to achieve the above object,

An organic electroluminescent display device comprising a substrate, a display unit disposed on one surface of the substrate, and a sealing substrate bonded to the substrate to seal the display unit.

An inlet portion having a flat portion and a sidewall portion, which is drawn into the surface of the sealing substrate toward the substrate with a predetermined depth; And

The organic light emitting display device of claim 1, wherein the at least one desiccant is coated to extend along at least one of the flat portion and the sidewall portion of the lead portion.

The desiccant may extend from the flat portion to the sidewall portion, and an end thereof may extend along an end portion of the sidewall portion.

The display unit may have an end portion located inside the end portion of the desiccant.

The desiccant may be transparent.

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

3 illustrates a screen printing method according to an exemplary embodiment of the present invention, which uses a screen mask member 40 having a screen mask 41 and a support member 43.

The screen mask 41 of the screen mask member 40 is provided with a screen portion 42 which allows the mixture placed thereon to penetrate and be patterned onto the substrate 30. The screen portion 42 is usually formed of a member such as a nylon cloth so as to penetrate the mixture of a predetermined particle size, and except for the screen portion 42 is formed by blocking the hole of the cloth using a curing agent. In addition to the screen mast 41, a polyester material, stainless steel, or the like may be used.

The support member 43 is bonded to the lower surface of the screen mask 41, but the support member 43 may be an oil, but is not limited thereto, and may support the screen mask 41. Anything is OK.

The support member 43 is provided with an opening 44 which is formed wider than the screen portion 42 of the screen mask 41. The screen mask 41, which is elastic with the opening 44, is squeezed 45. To release the mixture.

In the present invention, the end portion 42a of the screen portion 42 is spaced apart from the end portion 44a of the opening portion 44 by a predetermined distance toward the center of the opening portion 44. This separation distance is referred to as L, and when the thickness of the support member 43 is referred to as T, L is made to be T or more.

3, due to the thickness of the support member 43 when the elastically formed screen mask 41 is pressed by the squeeze 45 to reach the upper surface of the substrate 30, It is for not disturbing pattern formation.

If the separation distance L is made too long, the effect of supporting the screen mask 41 from the support member 43 is reduced, and it is discharged from the screen portion 42 of the screen mask 41 on the substrate 30. Since the applied admixture may diffuse and the boundary may be disturbed, an appropriate length may be used to prevent this. However, since the screen mask 41 is already under sufficient tension, the L may be set to about 10 of the thickness T of the supporting member 43 depending on the degree of tension applied to the screen mask 31.

According to the screen mask member 40 as described above, the support member 43 for adjusting the thickness of the mixture applied to the substrate 30, and for supporting the screen mask 41, the screen mask 41 and the substrate 30 In the case of intervening between), the amount of the mixture pattern corresponding to the screen portion 42 of the screen mask 41 can be obtained accurately.

In the present invention, the desiccant 52 may be applied to the sealing substrate 50 having the predetermined inlet portion 51 as shown in FIG. 4 using the screen mask member 40 as described above.

That is, as shown in FIG. 4, in the sealing substrate 50 having the flat portion 51a and the side wall portion 51b, the outer edges of the end portion 42a of the screen portion 42 and the lead portion 51 are formed. After the alignment, the desiccant is applied to the upper part of the screen mask 41 and pushed with a squeeze 45 to push the desiccant into the inlet 51 through the screen part 42.

At this time, the end portion 42a of the screen portion 42 enters inward from the opening portion 44 end portion 44a of the support member 43 by L, and thus the support member ( 43) does not act as an obstruction. Accordingly, the desiccant 52 can be applied to the flat portion 51a of the lead portion 51 accurately, and the desiccant 52 can be applied accurately to the side wall portion 51b if desired.

FIG. 5 illustrates an example of an organic light emitting display device manufactured by the manufacturing method. The substrate 60 having the display unit 21 and the sealing substrate 50 coated with the desiccant 52 are sealed. It is joined by the 53.

The substrate 60 may be a glass material, but is not limited thereto, and a plastic material, a film, or the like may also be used.

The display unit 61 may be an organic light emitting display unit, and the organic electroluminescent display unit may include a pair of electrodes facing each other and an organic layer disposed between the electrodes and including at least an organic light emitting layer. have. In this case, the organic light emitting display may be applied whether the driving scheme is a passive matrix or an active matrix.

The organic light emitting display is disposed such that an anode electrode for supplying holes and a cathode electrode for supplying electrons are opposed to each other, and the anode and cathode electrodes It consists of an organic layer arrange | positioned in between and emitting light. An anode electrode is formed on the substrate 60, an organic layer is formed thereon, and a cathode electrode is formed on the organic layer, but the present invention is not limited thereto, and the positions of the anode and cathode electrodes are reversed. It may be. In the case of an active driving type, the substrate 60 includes a plurality of thin film transistors, and the anode electrode is connected to the thin film transistors.

When the image is a rear emitting type implemented toward the substrate 60, the anode electrode may be formed as a transparent electrode, and the cathode electrode may be formed as a reflective electrode. In the case of a front emitting type in which an image is formed on the opposite side of the substrate 60, the anode electrode may be formed as a reflective electrode, and the cathode electrode may be formed as a transmissive electrode.

The anode electrode and the cathode electrode may be formed in a predetermined pattern, in the case of the active emission type, the cathode electrode may be entirely deposited. However, the present invention is not necessarily limited thereto and may be patterned.

As the organic layer interposed between the anode electrode and the cathode electrode, a low molecular or polymer organic layer may be used. When the low molecular organic layer is used, a hole injection layer (HIL), a hole transport layer (HTL), An organic emission layer (EML), an electron injection layer (EIL), an electron injection layer (ETL), and the like may be formed by stacking a single or a composite structure. Phthalocyanine (CuPc: copper phthalocyanine), N, N-di (naphthalen-1-yl) -N, N'-diphenyl-benzidine (N, N'-Di (naphthalene-1-yl) -N, N'- Diphenyl-benzidine (NPB), tris-8-hydroxyquinoline aluminum (Alq3), and the like can be applied in various ways. These low molecular weight organic layers can be formed by vacuum deposition.

In the case of the polymer organic layer, the structure may include a hole transporting layer (HTL) and a light emitting layer (EML). In this case, PEDOT is used as the hole transporting layer, and polyvinylvinylene (PPV) and polyfluorene are used as the light emitting layer. Polymer organic materials such as (Polyfluorene) are used and can be formed by screen printing or inkjet printing.

In such an organic layer, at least the light emitting layer EML may be patterned for each pixel of red (R), green (G), and blue (B) colors to implement a full color.

In the organic light emitting display unit, as anode and cathode voltages are applied to the anode electrode and the cathode electrode, holes injected from the anode electrode are moved to the light emitting layer, and electrons are injected from the cathode electrode to the light emitting layer. In this light emitting layer, electrons and holes recombine to generate excitons, and as the excitons change from an excited state to a ground state, fluorescent molecules in the light emitting layer emit light to form an image. In the case of a full color organic light emitting display device, a full color is realized by including pixels emitting three colors of red (R), green (G), and blue (B).

A passivation film made of an inorganic material, an organic material, or an organic-inorganic composite laminate may be further provided on the upper surface of the upper electrode of the display unit 61 manufactured as described above.

The sealant 53 is applied to the edge of the display portion 61, the sealing substrate 50 is bonded onto the sealant 53, and then the sealant 53 is cured to seal the display portion 61.

The sealing substrate 50 may be a transparent glass substrate or a plastic substrate, and is provided with an inlet portion 51 drawn in a predetermined depth on a surface facing the substrate 60.

The lead portion 51 is provided with a larger area than the area of the display portion 61, and may be provided to overlap the display portion 61, the edge boundary of which is located inside the portion where the sealant 53 is applied. do. The edge boundary of the lead portion 51 may be provided to extend along the sealant 53. The lead portion 51 may be provided in a substantially rectangular shape according to the shape of the display device.

The lead portion 51 may be provided with a flat portion 51a and a side wall portion 51b, but the side wall portion 51b may be inclined as shown in the figure, but is not limited thereto, and the flat portion 51a may be provided. It may be formed to be approximately perpendicular to the.

The wet and dry agent 52 is applied to the inlet portion 51 by using the screen mask member 40 in the same manner as in FIG. 4. At this time, the desiccant 52 is formed along the boundary of the flat portion 51a.

The desiccant 52 may be applied to any desiccant capable of absorbing moisture. More preferably, the desiccant 52 may maintain a transparent state even after absorbing moisture.

As the desiccant 52, a transparent nanoporous oxide layer including nano-sized porous oxide particles and containing nano-sized pores may be used.

The porous oxide particles may be at least one selected from the group consisting of alkali metal oxides, alkaline earth metal oxides, metal halides, metal sulfates and metal perchlorates having an average particle diameter of 100 nm or less.

In this case, the alkali metal oxide is lithium oxide (Li 2 O), sodium oxide (Na 2 O) or potassium oxide (K 2 O), and the alkaline earth metal oxide is barium oxide (BaO), calcium oxide (CaO), or magnesium oxide (MgO). And the metal sulfate is lithium sulfate (Li2SO4), sodium sulfate (Nai2SO4), calcium sulfate (CaSO4), magnesium sulfate (MgSO4), cobalt sulfate (CoSO4), gallium sulfate (Ga2 (SO4) 3), titanium sulfate (Ti) (SO4) 2), or nickel sulfate (NiSO4), and the metal halide is calcium chloride (CaCl2), magnesium chloride (MgCl2), strontium chloride (SrCl2), yttrium chloride (YCl2), copper chloride (CuCl2), Cesium fluoride (CsF), tantalum fluoride (TaF5), niobium fluoride (NbF5), lithium bromide (LiBr), calcium bromide (CaBr3), cerium bromide (CeBr4), selenium bromide (SeBr2), vanadium bromide (VBr2) (MgBr 2), barium iodide (BaI 2), or magnesium iodide (MgI 2), and the metal perchlorate is barium perchlorate (Ba (ClO 4) 2) or magnesium perchlorate Nesium (Mg (ClO 4) 2).

The average diameter of pores in the transparent nanoporous oxide film may be 100 nm or less.

In addition, the transparent nanoporous oxide film may be a transparent nanoporous calcium oxide (CaO) film.

The transparent nanoporous oxide film is a sol mixture obtained by dispersing nano-sized porous oxide particles in a solvent and an acid is applied to the inlet 51 of the sealing substrate 50 by using a screen printing method, as shown in FIG. This can be obtained by drying and heat treatment.

It is preferable that the said heat processing temperature is 250 degrees C or less, especially 100-200 degreeC. If the heat treatment temperature exceeds 250 ℃, the moisture absorption characteristics due to the reduction of the specific surface area by pre-sintering between particles is deteriorated, which is undesirable.

In the process of mixing the nano-sized porous oxide particles with a solvent and an acid, it is preferable to proceed in the following order in terms of dispersibility.

Solvent and acid are added to adjust the pH to a range of 1-8, especially about 2, followed by addition of nano-sized porous oxide particles. At this time, the acid may be optionally added.

The acid is an optional component, with the added advantage of improving dispersibility. Examples of the acid include nitric acid, hydrochloric acid, sulfuric acid, acetic acid and the like. And the content of the acid is preferably 0.01 to 0.1 parts by weight based on 100 parts by weight of the porous oxide particles.

The solvent may be used as long as it can disperse the porous oxide particles. Specific examples thereof include ethanol, methanol, propanol, butanol, and isopropanol. One or more selected from the group consisting of methyl ethyl ketone, pure water, propylene glycol (mono) methyl ether (PGM), isopropyl cellulose (IPC), methylene chloride (MC), ethylene carbonate (EC), and the content thereof Silver is 60 to 99 parts by weight based on 100 parts by weight of the porous oxide particles.

The transparent nanoporous oxide film formed by the manufacturing method of the present invention as described above is a thin film having a thickness of 0.1 µm to 12 µm, has sufficient moisture absorption and oxygen adsorption characteristics, and has an excellent function of sealing the display unit 51.

As described above, after preparing the sealing substrate 50 on which the transparent nanoporous oxide film is formed, the sealant 53 is formed on the sealing substrate 50 and a portion corresponding to the outside of the display portion 61 of the substrate 60. Apply. Subsequently, the organic light emitting display device of the present invention is completed by bonding the sealing substrate 50 and the substrate 60 together.

In some embodiments, the sealant may be further cured by using ultraviolet light, visible light, or heat after being vacuumed or filled with an inert gas in the internal space of the organic light emitting display device formed according to the above manufacturing process.

The transparent nanoporous oxide film formed by the above-described method has pores formed therein, and the film is kept transparent before or after absorbing the moisture. The pore should have an average diameter of 100 nm or less, preferably 70 nm or less, and more preferably 20 to 60 nm. If the average diameter of the pores exceeds 100nm it is not preferable because it does not have sufficient hygroscopic properties.

The transparent nanoporous oxide film formed by this method has the property of being kept transparent before or after absorbing moisture.

FIG. 6 illustrates an organic light emitting display device according to another exemplary embodiment of the present invention, in which a desiccant 52 extends to the sidewall portion 51b of the lead portion 51 so that an end thereof is at the sidewall. It is formed to extend along the end of the portion (51b). Other than that is the same as the above-mentioned embodiment.

5 and 6, when the organic electroluminescent display is formed, the desiccant 52 is formed wider than the area of the display 61 so that the end of the display 61 is inside the end of the desiccant 52. In this case, even when an image is realized in the direction of the sealing substrate 50, it is possible to solve the problem that the visibility of the screen is lowered due to the non-uniform shape of the desiccant 52 and the step of the end thereof.

As described above, the present invention is not necessarily limited to the organic light emitting display device, but may be applied to various flat panel display devices such as a liquid crystal display device and an inorganic electroluminescent display device.

According to the present invention made as described above can obtain the following effects.

First, in the screen printing method, a pattern corresponding to the screen portion of the screen mask can be obtained.

Second, in the board | substrate with an inlet part, when printing a mixture agent in an inlet part, it can print correctly inside an inlet part.

Third, the desiccant is formed wider than the area of the display portion so that the end portion of the display portion is positioned inside the end portion of the desiccant, so that even when an image is realized in the direction of the sealing substrate, the screen can be formed by the non-uniform shape of the desiccant and the step of the end thereof. This can solve the problem of poor visibility.

Although the present invention has been described with reference to one embodiment shown in the drawings, this is merely exemplary and will be understood by those of ordinary skill in the art that various modifications and variations can be made therefrom.

Claims (12)

In the screen printing method of screen printing a mixture on a substrate using a screen mask member, The screen mask member, A screen mask having a screen portion on which a mixture is printed in a predetermined pattern; And And a support member in contact with the screen mask, the support member having an opening having a width larger than that of the screen portion. Screen printing, characterized in that to form a mixture pattern corresponding to the screen portion by pressing a squeeze on the mixture on the screen mask in the state in which the screen mask member is disposed so that the support member faces the substrate. Way. The method of claim 1, And an end portion of the screen portion spaced apart from an end portion of the opening portion toward a center of the opening portion by a predetermined distance. The method of claim 2, The distance between the end of the screen portion is the distance from the end of the opening is referred to as L, the thickness of the support member T, the screen printing method, characterized in that L and T satisfy the following formula (1). L> = T The method of claim 1, The substrate is provided with a predetermined inlet, And the screen unit corresponds to the inlet unit. In the manufacturing method of the organic electroluminescent display device which screen-prints a desiccant with a screen mask member on the sealing substrate which has an inlet part, The screen mask member, A screen mask having a screen portion on which the desiccant is printed; And And a support member in contact with the screen mask, the support member having an opening having a width larger than that of the screen portion. In a state where the screen mask member is disposed so that the support part faces the sealing substrate, the desiccant placed on the screen mask is pressurized with a squeeze to form a desiccant pattern corresponding to the screen part. Method of manufacturing an organic electroluminescent display. The method of claim 5, And an end portion of the screen portion spaced apart from an end portion of the opening portion toward the center of the opening portion by a predetermined distance. The method of claim 6, The distance between the end of the screen portion and the end of the opening is referred to as L and the thickness of the support member as T, wherein the L and T satisfy the following equation (2). Manufacturing method. L> = T The method of claim 5, The substrate is provided with a predetermined inlet, And the screen unit corresponds to the lead-in unit. An organic electroluminescent display device comprising a substrate, a display unit disposed on one surface of the substrate, and a sealing substrate bonded to the substrate to seal the display unit. An inlet portion having a flat portion and a sidewall portion, which is drawn into the surface of the sealing substrate toward the substrate with a predetermined depth; And And a desiccant coated on the inlet, the ends of which are coated so that an end thereof extends at least along a boundary between the flat and sidewall portions of the inlet. The sealing substrate is provided transparently, The desiccant is a transparent organic electroluminescent display. The method of claim 9, And the desiccant extends from the flat portion to the sidewall portion, and an end portion thereof extends along an end portion of the sidewall portion. The method of claim 9 or 10, And the end portion of the display portion is positioned inside the end portion of the desiccant. delete

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