WO2016080719A1 - Metal-organic coordination polymer electroluminescent device - Google Patents

Abstract

The present invention relates to a metal-organic coordination polymer electroluminescent device and, more specifically, to an electroluminescent device comprising: a transparent electrode and a rear electrode provided so as to be spaced from each other at a predetermined interval; and a light emitting layer, or a light emitting layer and a dielectric layer, provided between the transparent electrode and the rear electrode, wherein the light emitting layer comprises a compound represented by the following chemical formula 1. The metal-organic coordination polymer compound of the present invention complements the advantages and compensates for the disadvantages of an organic phosphor and an inorganic phosphor, thereby exhibiting high reliance and efficiency while ensuring a wide color gamut (particularly red), and thus an excellent inorganic light emitting device can be implemented. [Chemical formula 1] [(A_x1,R_x2)(phen)₂(L)₃2(H₂O)]_n A is one selected from the group consisting of Y, La, Ga, Lu and Gd trivalent cation metals; R is one selected from the group consisting of Eu, Sm, Dy and Tb; phen is phenanthroline; and L is a compound represented by chemical formula 2.

Description

Metal-Organic Coordination Polymer Electroluminescent Devices

The present invention relates to a metal-organic coordination polymer electroluminescent device.

An electroluminescent element is roughly divided into two types, an organic electroluminescent element and an inorganic electroluminescent element whose luminescent compound is an inorganic substance.

 Among these, organic light emitting diodes (OLEDs) are applied to surface emitting displays with a rich color gamut and low power consumption, and are commercially available devices. However, organic electroluminescent devices (OLEDs) are characterized by having a light emitting mechanism centered on organic materials. Lifespan characteristics can be a major problem.

In contrast, the ELD has excellent reliability and lifespan characteristics, but has a disadvantage in that the color gamut is limited.

In addition, organic light emitting diodes (OLEDs) require a deposition technique due to the device structure, and thus, there is a problem in that the cost and defect rate thereof are high. Inorganic electroluminescent devices (ELDs) are a silk screen method, which is a printing technique. Simple lamination techniques such as printing method, spin coating method, and doctor blade coating method can be applied, resulting in high mass production rate. However, most electroluminescent high-luminescent phosphors are susceptible to moisture resistance due to sulfide composition. .

Accordingly, there is a demand for the development of phosphors capable of complementing the advantages and disadvantages of the organic phosphor and the inorganic phosphor as phosphors of the electroluminescent device.

An object of the present invention is to provide a complex hybrid type metal-organic coordination polymer compound that can complement the advantages and disadvantages of an organic phosphor and an inorganic phosphor.

The present invention has been made to solve the problems of the prior art,

Transparent electrodes and rear electrodes provided spaced apart from each other at predetermined intervals,

It comprises a light emitting layer, or a light emitting layer and a dielectric layer provided between the transparent electrode and the back electrode,

The light emitting layer provides an electroluminescent device characterized in that it comprises a compound represented by the following formula (1).

[Formula 1]

[(A _x1 , R _x2 ) (phen) ₂ (L) ₃ 2 (H ₂ O)] _n

A is one selected from the group consisting of Y, La, Ga, Lu, and Gd trivalent cation metals, R is one selected from the group consisting of Eu, Sm, Dy, and Tb, phen is phenanthroline, and L Is a compound represented by the following Chemical Formula 2, 0 < x1 + x2 <2 and n> 0.

[Formula 2]

Wherein R 1 is a carboxy residue having 2 to 5 carbon atoms, R 2 is hydrogen, a carboxy residue having 2 to 5 carbon atoms, or NR 3 R 4, and R 3 and R 4 are each independently hydrogen, oxygen, or a hydrocarbon having 1 to 10 carbon atoms, m is an integer from 2 to 4, and each of R1 may be the same or different from each other.

In the present invention, L is an electroluminescent device, characterized in that at least one residue selected from isophthalic acid, 5-aminoisophthalic acid, and 5-nitro isophthalic acid.

In addition, in the present invention, the light emitting layer provides an electroluminescent device, characterized in that having a thickness within the range of 100 to 1,000nm.

In the present invention, the light emitting layer further comprises a binder in the compound represented by the formula (1), the compound represented by the formula (1): binder = 4 to 6: electroluminescent, characterized in that having a weight ratio of 6 to 4 Provided is an element.

In the present invention, the dielectric layer is selected from PVDF (Poly-VinyliDene Fluoride), PVDF-Trfe, Polyvinylpyrrolidine, aluminum oxide (Al ₂ O ₃ ), and barium titanate (BaTiO ₃ ) It provides an electroluminescent device characterized in that it comprises at least one compound.

In addition, in the present invention, the transparent electrode, ITO (Indium Tin Oxide) is provided comprising an electroluminescent device, characterized in that made.

In addition, in the present invention, the rear electrode is provided with an electroluminescent device, characterized in that made of silver.

The metal-organic coordination polymer compound of the present invention has the effect of complementing the advantages and disadvantages of the organic phosphor and the inorganic phosphor, thereby ensuring a rich color gamut (especially red), and exhibiting high reliability and efficiency. It is possible to implement an excellent inorganic light emitting device.

1 is a PXRD graph of Example 1 of the present invention.

2 and 3 are SEM images of Example 1 of the present invention. 2 is a x2000 magnification, and FIG. 3 is a x5000 magnification.

4 is a diagram showing the structure of the electroluminescent element of the present invention.

5 is a photograph showing the electroluminescence phenomenon of the embodiment of the present invention.

6 is a graph showing the electroluminescence characteristics of the comparative example of the present invention.

7 is a graph showing the electroluminescence characteristics of Example 1 of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is demonstrated in detail.

4 is a diagram showing the structure of the electroluminescent element of the present invention.

As shown in Figure 4, the present invention,

Transparent electrodes and rear electrodes provided spaced apart from each other at predetermined intervals,

A light emitting layer is provided between the transparent electrode and the back electrode, or comprises a light emitting layer and a dielectric layer, the light emitting layer includes a light emitting compound.

In particular, the light emitting compound included in the light emitting layer is a metal-organic coordination polymers, and is a red light emitting material having a narrow half-width and a high luminance as compared with a conventional phosphor. In the conventional inorganic electroluminescent device, mainly as a sulfide-based phosphor, only blue, green, orange, and the like could be implemented, and red did not exist.

The light emitting compound of the present invention has a light emission wavelength of 600 to 630 nm and is a compound based on a structure in which Eu ₂₊ is added as an activator, more specifically, represented by the following formula (1).

[Formula 1]

[(A _x1 , R _x2 ) (phen) ₂ (L) ₃ 2 (H ₂ O)] _n

A is one selected from the group consisting of Y, La, Ga, Lu, and Gd trivalent cation metals, R is one selected from the group consisting of Eu, Sm, Dy, and Tb, phen is phenanthroline, and L Is a compound represented by the following Chemical Formula 2, 0 < x1 + x2 <2 and n> 0.

[Formula 2]

Wherein R 1 is a carboxy residue having 2 to 5 carbon atoms, R 2 is hydrogen, a carboxy residue having 2 to 5 carbon atoms, or NR 3 R 4, and R 3 and R 4 are each independently hydrogen, oxygen, or a hydrocarbon having 1 to 10 carbon atoms, m is an integer from 2 to 4, and each of R1 may be the same or different from each other.

L is preferably at least one residue selected from isophthalic acid, 5-aminoisophthalic acid, and 5-nitro isophthalic acid.

The light emitting layer preferably has a thickness within the range of 100 to 1,000 nm. If the thickness of the light emitting layer outside the above range is too thin, electroluminescence may not occur well, or there may be a possibility of not generating a sufficient amount of photons. Outside of the above range, if the thickness of the light emitting layer is too thick, the driving voltage is increased. There may be a problem.

The light emitting layer may be formed by mixing a compound represented by Formula 1 and a binder. At this time, it is appropriate to have a weight ratio of the compound represented by the formula (1): binder = 4-6: 6-4. The binder may preferably be a cellulose binder.

The dielectric layer is at least one compound selected from PVDF (Poly-VinyliDene Fluoride), PVDF-Trfe, Polyvinylpyrrolidine, Aluminum Oxide (Al ₂ O ₃ ), and Barium Titanate (BaTiO ₃ ). It may be to include.

The transparent electrode may be made of indium tin oxide (ITO), but the transparent conductive material is not particularly excluded.

The back electrode may be made of silver, but does not specifically exclude materials having good reflectivity and conductivity, such as copper and aluminum.

Hereinafter, an Example is given and this invention is demonstrated in detail. The following examples are only for the detailed description of the invention, it is made clear that it is not intended to limit the scope by this.

Example

Example 1

1.37 g of phenanthroline, 2.30 g of YCl ₃ · 6H ₂ O, 0.30 g of Eu (NO ₃ ) ₃ · 5H ₂ O, and 0.642 g of isophthalic acid were weighed and mixed in a H ₂ O 0.1 L solvent.

Thereafter, the mixture was reacted at a temperature of 130 ° C. to finally obtain a light emitting compound having a composition of [(Y _1.9 Eu _0.1 ) (phen) ₂ (L1) ₃ 2 (H ₂ O)] n (where phen is phenanthroline, L1 is a residue of isophthalic acid, n> 0).

In summary, the process is shown in Scheme 1.

A cellulose binder was kneaded with the luminescent compound (a luminescent compound: a cellulose binder = 4: 6 weight ratio), and a light emitting layer was formed by coating and drying the same on a ITO transparent electrode with a doctor blade. Thereafter, a dielectric layer including barium titanate and a silver back electrode were sequentially formed and stacked on the light emitting layer to finally manufacture an inorganic light emitting device. That is, the light emitting layer was laminated using ITO PET as a substrate using a silk screen technique using a slurry in which an appropriate amount of the present light emitting compound was mixed using a cellulose binder. After drying was carried out. Next, a dielectric layer was laminated and dried using a barium titanate slurry for dielectric layer deposition. Finally, the electrode was laminated using silver paste. When laminating by the above method, as shown in Table 1 below, a mesh was used to have an appropriate thickness, and the EL device was fabricated by repeating lamination with a silk screen method.

Table 1

Example 2

1.37 g of phenanthroline, 2.30 g of YCl ₃ · 6H ₂ O, 0.30 g of Eu (NO ₃ ) ₃ · 5H ₂ O, and 0.706 g of 5-amino isophthalic acid were weighed and mixed in a H ₂ O 0.1 L solvent.

Thereafter, the mixture was reacted at a temperature of 130 ° C. to finally obtain a light emitting compound having a composition of [(Y _1.9 Eu _0.1 ) (phen) ₂ (L2) ₃ 2 (H ₂ O)] n (where phen is phenanthroline, L2 is a residue of 5-amino isophthalic acid, n> 0).

In summary, the process is shown in Scheme 2.

Except for kneading the cellulose-based binder to the light-emitting compound (light-emitting compound: cellulose-based binder = 4: 6 weight ratio), except that the light emitting layer was formed by applying and drying it with a doctor blade on the ITO transparent electrode, all In the same manner as in Example 1, an inorganic light emitting device was manufactured.

Example 3

1.37 g of phenanthroline, 2.30 g of YCl ₃ · 6H ₂ O, 0.30 g of Eu (NO ₃ ) ₃ · 5H ₂ O, and 0.823 g of 5-nitro isophthalic acid were weighed and mixed in a H ₂ O 0.1 L solvent.

Thereafter, the mixture was reacted at 130 ° C. to finally obtain a light emitting compound having a composition of [(Y _1.9 Eu _0.1 ) (phen) ₂ (L3) ₃ 2 (H ₂ O)] n (where phen is phenanthroline, L3 is a residue of 5-nitro isophthalic acid, n> 0).

In summary, the process is shown in Scheme 3.

Except for kneading the cellulose-based binder to the light-emitting compound (light-emitting compound: cellulose-based binder = 4: 6 weight ratio), except that the light emitting layer was formed by applying and drying it with a doctor blade on the ITO transparent electrode, all In the same manner as in Example 1, an inorganic light emitting device was manufactured.

Comparative example

In Example 1, except that only the light-emitting compound included in the light-emitting layer was used for EuY, all of the light-emitting device was finally manufactured. (In fact, the electroluminescent property of EuY is not known in the prior art. It was used as a reference to compare the electroluminescent performance of

Experimental Example

Luminescent Compound Properties

The PXRD graph and the SEM image of Example 1 prepared above were the same as FIGS. 1 and 2 to 3, respectively.

Electroluminescence test

The inorganic electroluminescent devices of Examples 1 to 3 prepared above were tested for electroluminescence by applying power. The power used was 1.5kV, DC and 500V, 400Hz, and the red electroluminescence was confirmed in both. The results were as shown in the photograph shown in FIG.

Electroluminescence measurement

The inorganic electroluminescent devices of Examples 1 to 3 and Comparative Examples prepared above were tested for electroluminescence by applying power. When the power source used 1.5 kV, DC, 500 V, and 400 Hz, the electroluminescent element using EuY as a light emitting layer was optically measured.

The results are shown in FIGS. 6 and 7. FIG. 6 shows a comparative example (light emitting layer compound EuY), and FIG. 7 shows a Example 1 (light emitting layer compound EuY isophthalic acid).

As can be seen by comparing FIG. 6 and FIG. 7, in the case of the light emitting layer compound of the present invention, it was found that the light emitting performance was good while showing sharper peak characteristics.

Claims (7)

1. Transparent electrodes and rear electrodes provided spaced apart from each other at predetermined intervals,

   It comprises a light emitting layer, or a light emitting layer and a dielectric layer provided between the transparent electrode and the back electrode,

   The light emitting layer is characterized in that it comprises a compound represented by the formula (1).

   [Formula 1]

   [(A _x1 , R _x2 ) (phen) ₂ (L) ₃ 2 (H ₂ O)] _n

   A is one selected from the group consisting of Y, La, Ga, Lu, and Gd trivalent cation metals, R is one selected from the group consisting of Eu, Sm, Dy, and Tb, phen is phenanthroline, and L Is a compound represented by the following Chemical Formula 2, 0 < x1 + x2 <2 and n> 0.

   [Formula 2]

   

   Wherein R 1 is a carboxy residue having 2 to 5 carbon atoms, R 2 is hydrogen, a carboxy residue having 2 to 5 carbon atoms, or NR 3 R 4, and R 3 and R 4 are each independently hydrogen, oxygen, or a hydrocarbon having 1 to 10 carbon atoms, m is an integer from 2 to 4, and each of R1 may be the same or different from each other.
2. The electroluminescent device according to claim 1, wherein L is at least one residue selected from isophthalic acid, 5-aminoisophthalic acid, and 5-nitro isophthalic acid.
3. The electroluminescent device according to claim 1, wherein the light emitting layer has a thickness within a range of 100 to 1,000 nm.
4. The electroluminescent device according to claim 1, wherein the light emitting layer further comprises a binder in the compound represented by Chemical Formula 1, wherein the compound represented by Chemical Formula 1 has a weight ratio of: binder = 4 to 6: 6 to 4. .
5. The method of claim 1, wherein the dielectric layer is selected from Poly-VinyliDene Fluoride (PVDF), PVDF-Trfe, Polyvinylpyrrolidine, Aluminum Oxide (Al ₂ O ₃ ), and Barium Titanate (BaTiO ₃ ). The electroluminescent device is characterized in that it comprises at least one compound.
6. The electroluminescent device according to claim 1, wherein the transparent electrode comprises indium tin oxide (ITO).
7. The electroluminescent device according to claim 1, wherein the back electrode is made of silver.

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