KR20120084614A - Dispersion type inorganic electroluminescence lamp for low power and high brightness - Google Patents

Abstract

PURPOSE: A method for manufacturing a dispersion inorganic electroluminescent lamp with low power and high brightness is provided to decrease a driving voltage and improve brightness by promoting the movement of electrons near a fluorescent substance by a dielectric substance. CONSTITUTION: A fluorescent substrate emits light by receiving a voltage and exciting electrons. A dielectric substance(40) helps the electrons of the fluorescent substance to move. The fluorescent dielectric mixed ink includes dielectric substances of 2 to 20 weight%, fluorescent substances of 60 to 65 weight%, a binder of 30 to 35 weight%, defoamer of 0.1 to 0.2 weight%, and wetting and dispersing additives of 0.1 to 0.2 weight%.

Description

Low power high brightness decentralized inorganic electroluminescent lamp {DISPERSION TYPE INORGANIC ELECTROLUMINESCENCE LAMP FOR LOW POWER AND HIGH BRIGHTNESS}

The present invention relates to a low-power, high-brightness distributed inorganic electroluminescent lamp, and more particularly, to form a distributed inorganic electroluminescent lamp in which a substrate, a front electrode, a light emitting layer, a dielectric layer, and a back electrode are sequentially stacked. It is not composed of only the phosphor ink, but is composed of a phosphor dielectric mixed ink, so that the dielectric can help the electrons move in the vicinity of the phosphor, thereby lowering the driving voltage and improving luminance, and preventing the degradation of the phosphor. It relates to a low power high brightness distributed inorganic electroluminescent lamp that can improve the.

Electroluminescence (EL) is largely divided into organic or inorganic light emitting diodes (LEDs) such as organic light emitting diodes (OLEDs) and polymer organic light diodes (PLEDs), and diode-type pn junctions. It is divided into two types, one type of injection EL and a high field EL mainly composed of inorganic materials.

Inorganic ELs belonging to the high-level EL are divided into inorganic thin film EL (TFEL) and inorganic powder EL (Inorganic powder EL).

Among them, the distributed inorganic EL lamp technology, which was developed in 1936, was put to market in the 1950s, and was used in the market. However, its distributed inorganic EL lamp technology was poorly used due to low luminous brightness, high power driving device, and short lifetime of phosphor. . Zinc sulfide (ZnS) sulfide phosphors are mainly used, which has a long-standing problem of shortening lamp life due to low moisture, oxygen and thermal stability. Since the late 1980s, a method of coating phosphor surfaces with inorganic materials such as silicon dioxide (SiO₂) and aluminum oxide (Al₂O₃) has been developed and used successfully. With the spread of phosphors with a practical lifespan of more than 3,000 hours, lamps are being developed that can expand new markets.

FIG. 1 illustrates a conventional technology. Referring to the drawings, a distributed inorganic electroluminescent lamp according to the related art includes a substrate 10 ', a front electrode 20', a light emitting layer 30 'made of a phosphor, and a dielectric layer 40'. And a back electrode 50 'is sequentially stacked.

When voltage is applied to the front electrode 20 'and the back electrode 50', the phosphor constituting the light emitting layer 30 'is excited and emits light.

However, the distributed inorganic electroluminescent lamp according to the related art requires a high driving voltage in order to implement high brightness, which leads to an increase in power consumption.

That is, there is a problem that a high voltage must be applied to implement high luminance in electroluminescence because a smooth relationship cannot be formed between the load and electron movement at the interface level and the collision between the electron and the phosphor.

In addition, the dispersion type inorganic electroluminescent lamp according to the prior art has a problem that the competitiveness of the product due to the degradation of the phosphor and deterioration of life due to the high driving voltage as described above.

Despite the problems of the prior art as described above, except for a distributed inorganic electroluminescent lamp, nothing can be manufactured by the printing method, and although it is an old technology, the front electrode, the phosphor, the dielectric, and the back electrode of the lamp are old. All of these inks have been developed and have the possibility of printing production as a flexible flat panel display in the future. Therefore, there is a demand for technology development for improving luminance and power efficiency for a distributed inorganic electroluminescent lamp.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to construct a distributed inorganic electroluminescent lamp in which a substrate, a front electrode, a light emitting layer, a dielectric layer and a back electrode are sequentially stacked The light emitting layer is not composed of only the phosphor ink as in the prior art, but is composed of a phosphor dielectric mixed ink so that the dielectric can help the electrons move in the proximity of the phosphor, thereby lowering the driving voltage and improving luminance, and deteriorating the phosphor. To provide a low-power high-brightness distributed inorganic electroluminescent lamp that can improve the life by preventing the.

In order to achieve the above object, a low-power high-brightness distributed inorganic electroluminescent lamp according to the present invention, in a distributed inorganic electroluminescent lamp in which a substrate, a front electrode, a light emitting layer, a dielectric layer and a back electrode are sequentially stacked, the light emitting layer is And a phosphor dielectric mixed ink including a phosphor to which electrons are excited by applying a voltage to emit light, and a dielectric to help move electrons of the phosphor, and is printed and stacked on the front electrode.

In addition, the low-power high-brightness dispersion type inorganic electroluminescent lamp according to the present invention, the phosphor dielectric mixed ink, phosphor 60-65% by weight, binder 30-35% by weight, defoamer 0.1-0.2% by weight, wetting dispersant 0.1 Characterized by the addition of 2 to 20% by weight of the dielectric in relation to the total weight of the phosphor ink to the phosphor ink consisting of a composition ratio of ~ 0.2% by weight.

In addition, the low-power high-brightness dispersion type inorganic electroluminescent lamp according to the present invention, the dielectric material contained in the phosphor dielectric mixed ink, barium titanate (BaTiO ₃ ) is added to the phosphor ink 6% by weight relative to the total weight of the phosphor ink. It is characterized by.

In addition, the low-power high-brightness dispersion type inorganic electroluminescent lamp according to the present invention, wherein the light emitting layer is 30 ~ 60㎛ of the phosphor dielectric mixed ink on the front electrode by two consecutive printing to perform continuous printing before the ink is dried It is characterized in that laminated to the thickness.

In addition, the low-power high-brightness dispersion type inorganic electroluminescent lamp according to the present invention, wherein the dielectric layer is made of a dielectric ink containing a dielectric, the ink is dried after two consecutive printing before continuous printing, after the continuous printing The dielectric ink is laminated on the light emitting layer by a thickness of 20 to 40 μm by three times of repeated printing for additional printing.

According to the above configuration, the low-power, high-brightness distributed inorganic electroluminescent lamp according to the present invention is composed of a phosphor dielectric mixed ink rather than a light emitting layer not only composed of phosphor inks as in the prior art, so that the dielectric moves electrons in the proximity of the phosphor. It can help to reduce the driving voltage and at the same time improve the brightness, and to prevent the deterioration of the phosphor to improve the lifetime, and the light emitting layer is printed and compacted by the two times continuous printing method which continuously prints before the ink dries. By minimizing the pinhole (pore) by one density, there is an effect having a stable electrical characteristics.

1 is a structural diagram of a distributed inorganic electroluminescent lamp according to the prior art
Figure 2 is a structural diagram of a low power high brightness distributed inorganic electroluminescent lamp according to an embodiment of the present invention
FIG. 3 is a graph showing the calculated electric field intensity while changing the dielectric constant of the surrounding dielectric medium when the dielectric constant of the ZnS phosphor is 8.5 (at 2MHz).
Figure 4 is a graph showing the change in thickness of the light emitting layer according to the printing method and the number of printing
5a is a photograph at a magnification of 500 times after printing a light emitting layer once
5B is a photograph at a magnification of 500 times after printing the light emitting layer twice consecutively.
5c is a photograph in which the light-emitting layer is enlarged to 500x magnification after one additional printing in a dried state after printing the light emitting layer once
Figure 6a is a photograph showing the printing surface after printing the dielectric layer once
Figure 6b is a photograph showing the printing surface after two consecutive printing of the dielectric layer
Figure 6c is a photograph showing the printing surface of the dielectric layer repeated two times after repeated printing two times
Figure 6d is a photograph showing the printing surface of the dielectric layer repeated two times after repeated printing three times
7 is a graph showing the thickness change according to the printing method and the number of printing of the dielectric layer
8A is a graph showing luminance according to the content (%) of barium carbonate contained in the light emitting layer when the light emitting layer is continuously printed twice and the dielectric layer is printed twice after the continuous printing.
8B is a graph showing luminance according to the content (%) of barium carbonate contained in the light emitting layer when the light emitting layer is continuously printed twice, the dielectric layer is printed twice, and then repeatedly printed.
8C is a graph showing luminance according to the content (%) of barium carbonate contained in the light emitting layer when the light emitting layer is continuously printed twice, the dielectric layer is printed twice, and then repeatedly printed three times.
9A is a graph showing the capacitance according to the number of printing of the dielectric layer and the content of barium carbonate contained in the light emitting layer (%) when the light emitting layer is continuously printed twice.
9B is a graph showing the capacitance according to the number of printing of the dielectric layer and the content of barium carbonate contained in the light emitting layer (%) when the light emitting layer is additionally printed once after drying and printing once
Figure 10a is a graph showing the power consumption according to the method of printing the light emitting layer and the content (%) of barium carbonate contained in the light emitting layer when the dielectric layer is repeated twice after the continuous printing
Figure 10b is a graph showing the power consumption according to the method of printing the light emitting layer and the content (%) of barium carbonate contained in the light emitting layer when the dielectric layer is printed twice and then repeated twice
10c is a graph showing the power consumption according to the method of printing the light emitting layer and the content (%) of barium carbonate contained in the light emitting layer when the dielectric layer is repeatedly printed three times after two consecutive printings.

Hereinafter, a low power high brightness distributed inorganic electroluminescent lamp according to the present invention will be described in detail with reference to the embodiment shown in the drawings.

2 is a structural diagram of a low power high brightness distributed inorganic electroluminescent lamp according to an embodiment of the present invention.

Referring to the drawings, a low-power, high-brightness distributed inorganic electroluminescent lamp according to an embodiment of the present invention is a substrate 10, the front electrode 20, the light emitting layer 30, the dielectric layer 40 and the back electrode 50 are sequentially stacked Has a structure.

The substrate 10 may be a transparent glass substrate or a plastic substrate, which may serve as a base for stacking the front electrode 20, or a PET film for a flexible transparent substrate.

Meanwhile, in the exemplary embodiment of the present invention, the indium tin oxide (ITO) layer is sputtered on a PET film to remove the change factor caused by the conductive polymer. A film was used.

The front electrode 20 is formed by coating an indium tin oxide (ITO) layer on the substrate 10 by sputtering. In the case of using a flexible PET film as the substrate 10, The front electrode 20 is generally formed by printing and applying a polymer conductive ink, which is a transparent material.

In addition, since the front electrode 20 is located in front of the light emitting layer 30 and the emitted light must be emitted to the surface, it must be excellent in transmittance and electrical conductivity, and distributed inorganic electroluminescence according to the difference in surface resistance and conductivity. It is preferable to use a conductive material having a low resistance as much as possible because it causes the electric resistance in the lamp.

In the embodiment of the present invention, the light emitting layer 30 is configured to emit light by applying a voltage. In an embodiment of the present invention, the phosphor 60-65 wt%, the binder 30-35 wt%, the antifoaming agent 0.1-0.2 wt%, and the wet dispersion agent 0.1-0.2 It is composed of a phosphor dielectric mixed ink made by adding 2 to 20 wt% of a dielectric with respect to the total weight of the phosphor ink to a phosphor ink having a composition ratio of wt%.

The phosphor has a configuration in which electrons are excited to emit light by applying a voltage. In one embodiment of the present invention, a zinc sulfide (ZnS) phosphor is one of ZnS: Cu, Cl (or Al) that emits green light. In the phosphor, a blue green phosphor having a particle size distribution D50% of 25 to 26 μm was used.

The dielectric is configured to help the electrons move in the phosphor. In one embodiment of the present invention, a barium titanate having a size of 0.2 to 1.0 μm, which is a ferroelectric having a high dielectric constant to help the electrons move in the proximity of the phosphor ( BaTiO ₃ ) was adopted.

That is, the light emitting layer 30 ′ of the prior art illustrated in FIG. 1 is composed of only phosphors, and there is a problem of a distributed inorganic electroluminescent lamp requiring a high driving voltage in order to realize high brightness. The phosphor dielectric mixed ink constituting the light emitting layer 30 includes the dielectric capable of assisting the movement of electrons in the proximity of the phosphor, thereby enabling high brightness even at low voltage.

The emission luminance of the distributed inorganic electroluminescent lamp depends on the type and concentration of the phosphor, the type of insulator and conductor, the concentration of the emission center, the thickness of the insulating layer and the fluorescent layer, the applied voltage and frequency, and the following mathematical development It can be expressed as Equation 1.

Where L is the luminous intensity, η is the luminous efficiency, n ₀ is the electron density in the phosphor, Nc is the concentration of the emission center, λ is the electron free stroke, d is the relative thickness of the insulating and fluorescent layers, and E is the field strength in the fluorescent layer. , f is the frequency of the applied voltage.

In order for the phosphor to excite, the electric field strength throughout the lamp is not important, but the electric field strength at each ZnS phosphor particle position is rather important. The electric field surrounding one phosphor particle may be concentrated on the phosphor as shown in Equation 2 below by the surrounding medium having a high dielectric constant.

If the dielectric constant of the dielectric around the phosphor is εr₂ and the relative dielectric constant of the phosphor is εr₁, the local field strength E _ZnS in the concentrated phosphor can be calculated. Where Em is the average field strength and φ is the volume ratio of the ZnS grains.

In FIG. 3, when the dielectric constant of the ZnS phosphor is 8.5 (at 2 MHz), the intensity of the electric field generated while changing the dielectric constant of the surrounding dielectric medium is shown.

Looking at the drawings, it can be seen that the higher the dielectric constant value of the dielectric medium, the higher the field strength.

Therefore, in one embodiment of the present invention, instead of adopting a ferroelectric polymer resin having a low dielectric constant as a dielectric medium, barium titanate (BaTiO ₃ ), which is a ferroelectric having a high dielectric constant, is used to enhance the electric field strength concentrated on the phosphor. By doing so, the luminous luminance and luminous efficiency are improved.

On the other hand, the binder is configured to firmly attach the phosphor and the dielectric, and the dispersing agent is configured to uniformly disperse the phosphor and the dielectric.

The phosphor dielectric mixed ink according to an embodiment of the present invention includes a vehicle composition step, a phosphor ink composition step, and a phosphor dielectric mixed ink composition step.

The vehicle composition step is to pulverize the fluorine rubber FC2211 in the solid state to less than 10 × 10㎜ to make 35-40%, and then put in a beaker and weighed 60-65% of the dilution solvent to make a binder, the antifoaming agent 0.1 ~ 0.2% and a wet dispersant were added in a 0.1 ~ 0.2% weight ratio, and then stirred for about 15 hours to dissolve in a completely liquid phase. The filter was filtered through a filter to remove foreign substances that penetrated during the dissolution process and to filter out undissolved particles. Proceeded.

In the phosphor ink composition step, in forming the phosphor ink having a single phosphor added to the filtered binder, the ink aptitude was dried at 130 ° C. for 30 minutes to provide the required printability, and the filtered binder was placed in an empty container. 35% by weight, antifoaming agent 0.1-0.2% by weight, wetting and dispersing agent 0.1-0.2% by weight, fluorescent substance 60-65% by weight, and mixed, and then diluted 1.5 ~ 2% by weight of the diluent solvent was mixed for the first stirring 5 minutes at a rotational speed of 600rpm, and was dispersed for 10 minutes at 600rpm in a co-rotator.

In the phosphor dielectric mixing ink composition step, the phosphor ink composed of only phosphor powder by large and coarse powder particles, as in the prior art, increases power consumption, decreases luminance, and insulates due to the occurrence of pinholes and uneven thickness of the printing surface when the phosphor layer is printed. In one embodiment of the present invention is determined to provide a cause of the life degradation due to destruction in order to improve the printing density of the light emitting layer 30 evenly and the pinhole without the pinhole barium titanate (BaTiO ₃₎ as a dielectric in the composition of the conventional phosphor ink ) Was added to 2-20% by weight in 2% increments to confirm the change of printing characteristics and electrical characteristics according to the added conditions, and the ink suitability for each step to ensure printability after drying at 130 ℃ for 30 minutes. It is to create.

In addition, in one embodiment of the present invention, the light emitting layer 30 has 30 fluorescent dielectric mixed inks formed on the front electrode 20 by the above two steps by continuous printing before the ink is dried. It is characterized by being laminated to a thickness of ~ 60㎛.

In one embodiment of the present invention, in order to print the light emitting layer 30, a heavy squeegee having a hardness of 70 ° as a urethane material was rounded to a polished surface in the form of a 0.5 mm round to increase the transfer amount of ink. In order to prevent ink tack and backing due to the increase in amount, the plate making interval was set to 5 mm, the plate making interval was 5 mm, and the plate making time setting was changed to 3.0 sec. Printing speed 20cm / sec, coating speed 25cm / sec, printing pressure 5.20 kgf / cm 2, coating pressure 5.0 kgf / cm 2, printing angle 70 °, printing stop time 2sec after one printing was set.

In addition, in one embodiment of the present invention, if the phosphor dielectric mixed ink is printed once and then dried and the next printing proceeds, the pinhole generated during the first printing is formed as it is and the additional thickness is increased, but after the first printing In the second continuous printing in which wet is printed one more time, additional printing pressure is applied to the pinhole portion generated at the time of one printing, thereby increasing the transfer rate of the ink to make the pinhole portion very cumulative. By leveling the thickness and distributing it evenly, the unit density is increased to minimize the pinhole, so that two consecutive printings are performed to have stable electrical characteristics.

Figure 4 shows the thickness change of the light emitting layer 30 according to the printing method and the number of prints, in the drawing 1C is a one-time printing, 2C is a continuous printing two times, that is, a state that is not dried after one printing ( One additional printing in wet state), 1C1P is one additional printing in dry state after one printing, and% of horizontal axis is barium titanate as dielectric contained in light emitting layer 30 The content of (BaTiO ₃ ) is shown in the rest of the drawings.

Referring to the drawings, the thickness of the light emitting layer 30 showed a slight difference of 32 to 35 µm for one printing (1C) and 33 to 35 µm for two consecutive printings (2C). The additional printing pressure in the wet state proves the effectiveness of pinholes in one printing (1C), and the thickness of 50 ~ 54㎛ for one printing (1C1P) after one printing and drying. It can be confirmed that the additional thickness (1P) is laminated on an additional thickness on the dried surface after the first printing (1C).

5A to 5C show a photograph in which the printing surface according to the printing method and the number of times of printing of the light emitting layer is enlarged at a magnification of 500. Referring to the drawings, the opening of the mesh does not pass as shown in FIG. 5A during one printing (1C). Due to the solid particles, pinholes were generated, and in the case of two continuous printings (2C), as shown in FIG. 5B, the pinholes were reduced in one printing (1C), and the distribution of particles per unit area was increased to obtain an even printing surface. In the case of one-time additional printing (1C1P) after printing and drying once, as shown in FIG. You can see the phenomenon.

The dielectric layer 40 is configured to insulate the light emitting layer 30 and the back electrode 50 from each other and to facilitate the movement of electrons when power is applied. The dielectric constant is high for maintaining electrical properties. In one embodiment of the present invention, a ferroelectric barium titanate (BaTiO ₃ ) is adopted as the dielectric included in the light emitting layer 30.

Dielectric layer 40 according to an embodiment of the present invention is made of a dielectric ink, the dielectric ink is a high dielectric material such as barium titanate (BaTiO ₃ ), not to use only a polymer resin, a ferroelectric having a low dielectric constant, as a dielectric medium. By mixing a solid ferroelectric having a dielectric constant value, an electric field intensity concentrated on the light emitter 30 was further enhanced to improve the light emission luminance and light emission efficiency. The preparation of the dielectric ink is similar to that of the phosphor ink described above. After measuring 45-50% of the filtered fluororubber binder in an empty container, the defoaming agent 0.1-0.2%, the wet dispersant 0.8-1.0%, the dielectric 50-55% After diluting and mixing, dilute solvent was added 1.0 ~ 1.5% and proceeded for 5 minutes at a rotation speed of 600rpm in the stirrer for the first stirring, and dispersed for 10 minutes at 600rpm in a co-rotating disperser and dried at 130 ° C for 30 minutes. It was designed to have printability.

In addition, in one embodiment of the present invention, the dielectric layer 40 is subjected to two consecutive printings (2C) for continuous printing before the ink is dried, and to three repeated printings (3P) for additional printing after the ink is dried. The dielectric ink is laminated on the light emitting layer 30 to have a thickness of 20 to 40 μm.

In one embodiment of the present invention, to print the dielectric layer 40, a heavy squeegee having a hardness of 70 ° as a urethane material was rounded to a polished surface in the form of a 0.5 mm circle to increase the transfer amount of ink. In order to prevent ink tack and backing due to the increase of the amount, the plate making interval was set to 6 mm, the plate making interval was 7 mm, and the plate making time setting was changed to 4.0 sec. Printing speed 20cm / sec, coating speed 25cm / sec, printing pressure 5.20 kgf / cm 2, coating pressure 5.0 kgf / cm 2, printing angle 70 °, printing stop time 2sec after one printing was set.

6A to 6D illustrate the printing surface of the dielectric layer according to the printing method and the number of printing times. Referring to the drawings, in the case of one-time printing (1C) of the dielectric ink, as shown in FIG. 6A, the surface is rough and the ink is rough. In the case of two consecutive printings (2C), the pinholes are filled as shown in FIG. 6B as in the case of printing the light emitting layer 30, and the number of times of printing is shown in FIGS. 6C and 6D. It can be seen that the printing surface becomes uniform as it increases.

7 shows the thickness variation according to the printing method and the number of printing of the dielectric layer. Referring to the drawings, there was a slight difference of 8 μm in one printing (1C) and 9 μm in two consecutive printings (2C). The additional printing pressure in the wet state where the surface is not dried proves the effect of pinholes in one printing (1C), and as the number of printing increases, the amount of ink transfer due to the printing pressure increases. It can be seen that the thickness is increased.

8A to 8C illustrate the luminance according to the number of prints of the dielectric layer 40 and the content of barium carbonate contained in the light emitting layer 30 after the continuous printing 2C of the light emitting layer 30. Referring to the drawings, the luminance was increased when the applied voltage and frequency were adjusted upward, and the luminance of the ink composition having a content of barium carbonate (BaTiO ₃ ), which is a dielectric contained in the light emitting layer 30, was 6% compared to the same applied voltage and frequency. It was found that the characteristics were excellent, and that the content of barium carbonate (BaTiO ₃ ) is again downward at a content of 6% or more.

According to the experimental results as described above, the dielectric material included in the phosphor dielectric mixed ink constituting the light emitting layer 30 in the dispersion type inorganic electroluminescent lamp according to the embodiment of the present invention is barium titanate (BaTiO ₃ ). It is characterized in that 6% by weight is added to the total weight of the phosphor ink.

9A to 9B, the capacitances of the respective ink compositions are shown. Referring to the drawings, the light emitting layer 30 is measured twice according to the number of times the dielectric layer 40 is printed after the continuous printing 2C. After the one-time printing and drying after one additional printing (1C1P) and the change in the ink composition under the same conditions according to the number of printing of the dielectric layer 40 was measured, the result is the continuous printing of the light emitting layer 30 twice (2C ), The capacitance was high, the capacitance increases as the content of barium titanate (BaTiO ₃ ) contained in the light emitting layer 30 increases, and the capacitance increases as the number of times of printing of the dielectric layer 40 increases. You can see that it appears low.

Meanwhile, FIGS. 10A to 10C illustrate power consumption according to the method of printing the light emitting layer and the dielectric layer, the number of printing times, and the content (%) of barium titanate contained in the light emitting layer.

Referring to the drawings, the number of times of printing the dielectric layer 40 is twice, depending on the case where the light emitting layer 30 is continuously printed twice (2C) and when the light emitting layer 30 is once printed and dried once (1C1P). After continuous printing, printing was repeated by one-time printing (2C1P) and measured by applying voltage and frequency at 100 V 400 니. As shown in FIG. Is 0.97 ~ 1.25 W and the average power consumption was 1.13 W. When the light-emitting layer 30 was printed and dried once, one additional printing (1C1P) was 0.40 to 0.58 W and the average power consumption was 0.50 W. .

In addition, the number of prints of the dielectric layer 40 was continuously printed twice, followed by two repeated printings (2C2P), and a result of measuring the voltage and frequency at 100 V 400 Hz and measuring the light emitting layer 30 as shown in FIG. In the case of continuous printing (2C), the power consumption was 0.79 to 1.06 W, and the average power consumption was 0.96 W, and 0.37 to 0.52 W in the case of additional printing (1C1P) after printing and drying the light emitting layer 30 once. As a result, the average power consumption is 0.46 W.

 In addition, the number of prints of the dielectric layer 40 was continuously printed twice, and then repeated three times (2C3P), and the result of measurement by applying a voltage and a frequency at 100 V 400 는 was obtained. In the case of continuous printing (2C), the power consumption was 0.72-0.93 W, and the average power consumption was 0.82 W, and in the case of additional printing (1C1P) once after printing and drying the light emitting layer 30, it was 0.36-0.47 W. It can be seen that the average power consumption is 0.42 W.

In summary, when the light emitting layer 30 is continuously printed twice (2C), it is possible to obtain an even printing surface by reducing the pinhole and increasing the particle size distribution per unit area. This is because the printing surface is not wet. It can be confirmed that the additional printing pressure in the state has the effect of pinholes in one printing (1C), and the pinhole of the dielectric layer 40 and the protrusion of the printing surface of the light emitting layer 30 are the main factors of breakdown. As a result, the formation of a flat surface without pinholes can reduce the occurrence of quality defects due to insulation breakdown within a shorter period of time than the service life.

In addition, as a result of comparing the characteristics of the respective ink compositions, the dispersed inorganic electroluminescence in which the light emitting layer 30 was composed of a phosphor dielectric mixed ink in which barium titanate (BaTiO ₃ ) was mixed with 6% as a dielectric in a phosphor layer ink made of only a vehicle and a phosphor. When the lamp was driven under the same driving conditions, the average power consumption was reduced by 12.1%, the capacitance by 2.4%, and the brightness by 10.0%.

The back electrode 50 is configured to form an electrode in pairs with the front electrode 20. In one embodiment of the present invention, in forming the back electrode 50 with a conductive ink, the resistance is lowered and the conductivity is increased. To produce a paste that has excellent ink dissipation and transferability on the plate making process and does not generate cracks after printing, Ag particles are pulverized in a ball mill to 1 ~ 2㎛ or less and the solid content ratio is 70 ~ 75%. Organic solids containing 8% and organic solvents containing 19% of diethylene glycol monoethyl ether acetate as a main component were mixed and dried to obtain printability after drying at 130 ° C. for 30 minutes.

On the other hand, the back electrode 50 in the embodiment of the present invention to increase the transfer amount of the ink by rounding the polishing surface in the form of a 0.5mm circular squeegee with a hardness of 70 °, In order to prevent ink tack and backing, the plate making interval was set to 6 mm, the plate making interval was 8 mm, and the plate making time was changed to 5.0 sec. Printing was performed at a printing speed of 20 cm / sec, a coating speed of 25 cm / sec, a printing pressure of 5.20 kgf / cm 2, a coating pressure of 5.0 kgf / cm 2, and a printing angle of 70 °.

The distributed inorganic electroluminescent lamp described above and shown in the drawings is only one embodiment for carrying out the present invention, and should not be construed as limiting the technical idea of the present invention. The scope of protection of the present invention is defined only by the matters set forth in the claims below, and the embodiments which have been improved and changed without departing from the gist of the present invention will be apparent to those skilled in the art. It will be said to belong to the protection scope of the present invention.

10 substrate
20 front electrode
30 light emitting layer
40 dielectric layers
50 back electrode

Claims (5)

In a distributed inorganic electroluminescent lamp in which a substrate, a front electrode, a light emitting layer, a dielectric layer, and a back electrode are sequentially stacked,
The light emitting layer is a low-power, characterized in that the phosphor is mixed with a phosphor dielectric mixed ink containing a fluorescent material that is excited and emits light by applying a voltage, and a dielectric material to help the electrons of the phosphor is printed and laminated on the front electrode High brightness decentralized inorganic electroluminescent lamp. The method of claim 1,
The phosphor dielectric mixed ink is composed of 60 to 65% by weight of a phosphor, 30 to 35% by weight of a binder, 0.1 to 0.2% by weight of an antifoaming agent, and 0.1 to 0.2% by weight of a wet dispersion agent. Low-power high-brightness distributed inorganic electroluminescent lamp, characterized in that by adding 2 to 20% by weight of a dielectric in preparation. The method of claim 2,
The dielectric material included in the phosphor dielectric mixed ink is barium titanate (BaTiO ₃ ), wherein the phosphor ink is added to the phosphor ink by 6 wt% based on the total weight of the phosphor ink. 4. The method according to any one of claims 1 to 3,
The light emitting layer is a low-power, high-intensity dispersion type inorganic electroluminescent lamp, characterized in that the phosphor dielectric mixed ink is laminated on the front electrode in a thickness of 30 ~ 60㎛ by two continuous printing before the ink is dried. . 4. The method according to any one of claims 1 to 3,
The dielectric layer is made of a dielectric ink containing a dielectric material, and the dielectric ink is applied to the light emitting layer by two repetitive printings in which continuous printing is performed before the ink is dried, followed by three repetitive printings after the ink is dried. Low-power high-brightness distributed inorganic electroluminescent lamp, characterized in that is laminated to a thickness of 20 ~ 40㎛.

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