KR20030030605A - Electrochromic display and method for fabricating the same - Google Patents

Abstract

PURPOSE: An electrochromic display and a method for manufacturing the same are provided to remove problems of the image diffusion in the electrochromic display by a partition structure using a photoresist. CONSTITUTION: A plurality of first electrode lines are formed on a first glass substrate(50). A counter electrode stabilizing an electrochromic display is formed on the first electrode lines. A photoresist is applied on the counter electrode to form partitions(53). A plurality of second electrode lines(62a,62b,62c) formed of an ITO film are formed on a second glass substrate(63). A plurality of pixels(61a,61b,61c) formed of an electrochromic material film are formed on the second electrode lines. Ion conductive thin films are deposited on the plurality of pixels and electrolytes are accumulated on the ion conductive thin films, so that the ion conductive thin films form high threshold voltage to prevent crosstalk.

Description

Electrochromic display and method for manufacturing the same {Electrochromic display and method for fabricating the same}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrochromic display (ECD) and a method of manufacturing the same, and more particularly, to an electrochromic display and a method of manufacturing the same, which can remove an image diffusion by installing a partition structure using a photoresist. .

In general, electrochromic displays are used for controlling light transmittance or reflectivity of windows or mirrors by using a principle that the color of an electrochromic material is changed when an electric field is applied. It is applied to the production of electronic books.

The electrochromic material is classified into an inorganic electrochromic material and an organic electrochromic material, and representative inorganic electrochromic materials are WO ₃ , NiO _x H _y , Nb ₂ O ₅ , V ₂ O ₅ , TiO ₂ , MoO _3, and the like, and typical organic electrochromic materials include polyaniline.

Taking the example of the inorganic electrochromic material WO ₃ will be described the principle of discoloration when applied to the electric field. WO ₃ reacts with ions or electrons in the electrolyte and discolors through the following process.

Formula

WO ₃ (transparent ^{color) + xe - + xM + ⇔} M x WO 3 ( dark blue)

Where x is the reaction constant and M is lithium (Li) or calcium (Ca) Ions are mainly used, and lithium is most commonly used, and lithium ion is WO₃By reacting with, the electrochromic effect is exhibited in this way.

In order to supply the lithium ions, an electrolyte is required, and the electrolyte includes a liquid and a solid polymer electrolyte. Solid polymer electrolyte is a material that can transfer ions in the solid state, unlike liquid electrolyte, there is no problem such as leakage of liquid when manufacturing the device, it is environmentally friendly, thin film is possible, it has the advantage that it can be manufactured in the desired form. .

Due to these advantages, development of a polymer electrolyte membrane having high ionic conductivity, excellent shape, chemical stability, and mechanical strength as well as a separator as well as a fuel cell or a secondary battery has emerged as the most important key issue.

1 is a basic configuration diagram of a conventional electrochromic display, in which upper and lower electrodes 2 and 5 are formed on one surface of each of upper and lower glass substrates 1 and 6, and an upper surface of the lower electrode 5 is formed. The electrochromic material 4 is coated to position the electrodes 2 and 5 of the upper and lower glass substrates 1 and 6 so as to form a predetermined space in a direction orthogonal to the upper and lower glass substrates. The sides of 1,6 are sealed with epoxy, leaving enough space to inject the solution, and when the electrolyte is injected into the space left by the epoxy, the most basic passive matrix display structure is obtained. It is finished.

The conventional electrochromic display may be applied to a display by applying a voltage to the upper and lower electrodes 2 and 5 to generate a corresponding dot of a portion where two electrodes cross at right angles.

FIG. 2 is a plan view illustrating a state in which an electrochromic color is displayed on an electrochromic display, wherein a fifth horizontal line 12 and a vertical line 11 intersect the second horizontal line 12 on a display using an electrochromic device having a pixel number of 3 × 3. When + 3V is applied to the second horizontal line 12 and 0V is applied to the second vertical line 11 so as to generate color to the pixel 25, the fifth pixel 25 is applied with a voltage of 2.5V. It changes to the desired color. However, 1.06V and 0.95V are applied to the fourth and sixth pixels 24 and 26 present in the second horizontal line 12 to generate color, and the second and eighth pixels present in the second vertical line 11. Voltages of 0.96 V and 1.06 V are also applied to (22, 28), which causes color problems.

Color development occurs in the above adjacent pixels is called a cross talk phenomenon.

The cause of the crosstalk phenomenon is firstly related to the threshold voltage of the interface between the electrochromic material and the electrolyte, and when the threshold voltage is low, a voltage is applied to the neighboring pixels, resulting in an electrochromic effect.

Such a threshold voltage is a voltage at which a small current flows until a constant voltage is reached, but a large current flows when the threshold voltage is higher than a predetermined voltage. In the case of an electrochromic display using a threshold voltage, the color does not appear when a small current flows. If a lot flows, the color appears.

Second, due to the image diffusion caused by the electrolyte between the upper and lower substrates connected to all the pixels.

Due to the crosstalk phenomenon, the electrochromic display has no choice but to be applied to simple devices such as smart windows or rear mirrors that do not require patterning.

Accordingly, an object of the present invention is to provide an electrochromic display that can eliminate crosstalk in a partition structure using photoresist.

Another object of the present invention is to provide a manufacturing method of an electrochromic display that can improve the color development characteristics by applying a solid electrolyte having a predetermined thickness and a partition wall made of a photoresist.

A preferred aspect for achieving the above object of the present invention comprises: first electrode lines arranged under the first glass substrate;

A second electrode line formed on the second glass substrate facing the first glass substrate so as to cross and face the first electrode lines;

A plurality of pixels on the upper portions of the second electrode lines, each of which includes an electrochromic material film which discolors the intersection of the first and second electrode lines according to an electric field, and has a separation space between the respective pixels;

A photoresist barrier rib formed to protrude below the first electrode lines and inserted into a space between the plurality of pixels;

An electrochromic display is provided, comprising a solid polymer electrolyte formed between an upper portion of the plurality of pixels and the first electrode lines.

According to another aspect of the present invention, there is provided a method of forming a first electrode line on a lower portion of a first glass substrate;

Forming a partition wall using photoresist on the first electrode lines;

Forming second electrode lines on the second glass substrate facing the first organic substrate;

Forming a plurality of pixels of an electrochromic material film on top of the second electrode lines such that each pixel has a separation space therebetween;

Forming a solid polymer electrolyte on the plurality of pixels;

The barrier rib of the first glass substrate is inserted into the separation space of the pixels of the second glass substrate, the electrolyte contacts the second electrode lines, and the first electrode line intersects the second electrode line. Provided is a method of manufacturing an electrochromic display comprising the step of assembling a first glass substrate and a second glass substrate at a constant pressure.

1 is a basic configuration diagram of a conventional electrochromic display.

2 is a plan view illustrating a state in which electrochromic colors appear on an electrochromic display.

3A to 3D are process diagrams for forming a partition on a first glass substrate of an electrochromic display according to the present invention.

Figures 4a to 4d is a process chart laminated on the second glass substrate of the electrochromic display according to the present invention.

5 is a perspective view illustrating a state in which a partition wall of a first organic substrate of the electrochromic display according to the present invention is fastened to a second organic substrate.

6 is a cross-sectional view illustrating a state in which a partition is positioned on a second glass substrate of the electrochromic display according to the present invention.

7 is a cross-sectional view showing a state in which the electrochromic display according to the present invention is completed.

<Description of the symbols for the main parts of the drawings>

50,63: first and second glass substrates 51 ,: first electrode line

52 counter electrode 53 partition wall

60a, 60b, 60c: ion conductive thin film 61a, 61b, 61c: pixel

62a, 62b, 62c: second electrode line 70a, 70b, 70c: electrolyte

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

3A to 3D are process diagrams for forming a partition on a first glass substrate of an electrochromic display according to the present invention, wherein a plurality of first electrode lines 51 are formed on the first glass substrate 50 (FIG. 3a), a counter electrode 52 is formed on the first electrode lines 51.

Meanwhile, the counter electrode 52 functions as a counter electrode with the first electrode lines 51 made of a transparent indium tin oxide (ITO) film, and functions as TiO ₂ + 0.25 CeO ₂ (with TiO ₂ at a composition ratio). TiO ₂ +0.25 CeO ₂ thin film having CeO ₂ of 1: 0.25) is formed on the first electrode lines 51. When the electrochromic display is operated, the counter electrode 52 may serve to store electrons that are moved during oxidation and reduction reactions associated with electrochromic, thereby stabilizing the device.

As shown in FIGS. 3C and 3D, a photoresist 53 is coated on the counter electrode 52, and a partition is formed using the photoresist.

The process of forming the partition wall using the photoresist is optimized in two types, namely, the partition wall is formed on the counter electrode 52 and the partition wall is formed on the first electrode line made of the ITO film. You can.

1) A method of forming partition walls with photoresist on the counter electrode

① Spin coating the upper portion of the counter electrode 52 at 1500 rpm for 30 seconds. Spin coating may be performed at 250 rpm to 1500 rpm, and may be performed for 5 to 30 seconds to form a photoresist film.

② Soft Baking is performed at 65 ° C. for 3 minutes in the first step and 10 minutes at 95 ° C. in the second step.

③ Exposure is performed on the photoresist film on which the soft baking is completed for 30 seconds through the mask on which the partition pattern is formed.

(4) Post Exposure Baking (PEB) is performed at 65 ° C. for 1 minute in the first step and 3 minutes at 115 ° C. in the second step.

⑤ After 5 minutes of development, the partition remains and the photoresist other than the partition is removed.

⑥ After washing in alcohol for 1 minute, dry it.

⑦ Hard baking for a total of 30 minutes, such as 10 minutes at 100 ℃, 10 minutes at 150 ℃ and 10 minutes at 200 ℃ is to form a partition on the counter electrode 52.

2) a method of forming a partition on the first electrode line made of an ITO film

① Spin coating the upper portion of the first electrode lines 51 at 1000 rpm for 30 seconds. Spin coating may be performed at 250 rpm to 1000 rpm, and may be performed for 5 to 30 seconds to form a photoresist film.

② Soft Baking is performed at 65 ° C. for 10 minutes in the first step and at 60 ° C. for 60 minutes in the second step.

③ Exposure is performed on the photoresist film on which the soft baking is completed for 60 seconds through the mask on which the partition pattern is formed.

(4) Post Exposure Baking (PEB) is performed at 65 ° C. for 5 minutes in the first step and 10 minutes at 115 ° C. in the second step.

⑤ When the development is carried out for 10 minutes, the partition wall remains, and the photoresist other than the partition is removed.

⑥ After washing in alcohol for 1 minute, dry it.

⑦ Hard baking for a total of 30 minutes such as 10 minutes at 100 ° C., 10 minutes at 150 ° C., and 10 minutes at 200 ° C. is to form a barrier rib on the top of the first electrode line made of ITO film.

4A to 4D illustrate a process of stacking an upper surface of a second glass substrate of the electrochromic display according to the present invention, wherein second electrode lines 62a, 62b, and 62c are formed of an ITO film on the second glass substrate 63. 4A, and a plurality of pixels 61a, 61b, and 61c formed of an electrochromic material film are formed on the second electrode lines 62a, 62b, and 62c (FIG. 4B).

In FIG. 4C, ion conductive thin films 60a, 60b and 60c are deposited on the plurality of pixels 61a, 61b and 61c, and an electrolyte is formed on the ion conductive thin films 60a, 60b and 60c. Stacking of the fields 70a, 70b, 70c completes the stacking of the electrochromic display components on top of the second glass substrate 63 (FIG. 4D).

The ion conductive thin films 60a, 60b, and 60c may have a high threshold voltage between the plurality of pixels 61a, 61b, and 61c of the electrochromic material film and the electrolytes 70a, 70b, and 70c. To prevent crosstalk.

The ion conductive thin films 60a, 60b, and 60c may preferably use a 0.2LiO ₂ -0.2CeO ₂ -0.6SiO ₂ single layer thin film containing a silicon oxide (SiO ₂ ) component.

However, the ion conductive thin films 60a, 60b, and 60c are thin films which can be formed as necessary, and are not necessarily required.

FIG. 5 is a perspective view illustrating a state in which a partition wall of the first glass substrate of the electrochromic display according to the present invention is fastened to the second organic substrate, and FIG. 4D illustrates the first glass substrate of FIG. 3D in which the partition wall 53 is formed. Stacked upside down on the second glass substrate shown in Figure 1, the partition wall 53 is inserted between the electrolyte 70a and the other electrolyte 70b, a predetermined pressure in the shape that the first electrode line and the second electrode line intersect When the mounting is applied, the assembly of the electrochromic display of the present invention is completed.

And, in order to prevent the penetration of moisture from the outside, around the two bonded substrates is sealed with a silicone-based UV sealing agent. Then, when ultraviolet rays are cured by irradiating ultraviolet rays at 40 mJ for 200 seconds, the electrolyte can be maintained in a solidified form.

When the electrolyte is solidified in this way, stable ion exchange is performed between the solidified electrolyte and the electrochromic material according to the voltage applied to the electrode line.

The electrolyte applied in the present invention is most preferably a solid polymer electrolyte, the solid polymer electrolyte is Poly-AMPS (2-Acrylamino-2-methylpropane sulfonic acid), PEO (Poly (ethylene oxide)), Poly (VAP (Vivilacochol- phosphoric acid) and LiCF ₃ SO ₃ can be applied.

FIG. 6 is a cross-sectional view illustrating a state in which a partition is positioned on a second glass substrate of an electrochromic display according to the present invention, and a partition is formed in a space between electrolytes 70a, 70b, and 70c formed on the plurality of pixels. 53 is positioned.

7 is a cross-sectional view showing a state in which an electrochromic display according to the present invention is completed, and includes first electrode lines 51 arranged under the first glass substrate 50; Second electrode lines 62 formed on an upper portion of the second glass substrate 63 opposite to the first glass substrate 50 so as to cross and face the first electrode lines 51; The second electrode lines 62a, 62b, and 62c are formed to be separated from each other between the first and second glass substrates 50 and 63 so as to be separated from each other, and when the electric field is applied, the first and second electrode lines ( A plurality of pixels 61a, 61b, 61c made of an electrochromic material film in which the portions where the cross points 51, 62 intersect are discolored; Electrolytes (70a, 70b, 70c) formed below the first electrode line (51) and above the plurality of pixels (61a, 61b, 61c); An electrochromic display may be formed of barrier ribs 53 protruding below the first electrode line 51 and inserted into a space between the plurality of pixels 60a, 60b, 60c.

And, as shown in Figure 7, between the first electrode line 51 and the electrolyte to store the electrons that are moved during the oxidation and reduction reaction due to electrochromic, TiO ₂ in the composition ratio And a counter electrode 52 made of a TiO ₂ +0.25 CeO ₂ thin film having CeO ₂ of 1: 0.25.

In addition, ion conductive thin films 60a, 60b, and 60c may be further provided as necessary to form a high threshold voltage between the electrolytes and the second electrode lines to prevent image diffusion.

In addition, a partition wall 53 is inserted into each of the neighboring spaces of the electrolytes 70a, 70b, 70c, the ion conductive thin films 60a, 60b, 60c, and the plurality of pixels 60a, 60b, 60c. The partition wall 53 may be mounted to extend to a space between the second electrode lines 62a, 62b, and 62c.

In Table 1, the voltage of each pixel was measured after applying voltage to the fourth electrode line vertically and the fourth electrode line horizontally in the electrochromic display when the partitions existed and the partitions did not exist.

Here, the first voltage value of each pixel is the measured voltage of the electrochromic display in which no partition is present, and the second voltage value is the measured voltage of the electrochromic display forming the partition.

-1.18V-0.06V -0.83V-0.03V -0.54V-0.01V 3.18V0.11V -0.24V-0.01V -0.20V-0.01V -0.18V-0.01V -1.26V-0.06V -0.89V-0.03V -0.59V-0.01V 3.43V0.11V -0.27V-0.01V -0.22V-0.01V -0.20V-0.01V -1.30V-0.06V -0.93V-0.03V -0.63V-0.01V 4.0V0.12V -0.28V-0.01V -0.23V-0.01V -0.20V-0.01V 9.45V0.79V 7.34 V 0.46 V 5.78V0.24V 10 V 3.86V0.12V 3.35V0.11V 3.10V0.11V -1.62V-0.12V -1.25V-0.06V -0.97V-0.03V 5.96V0.24V -0.64V-0.01V -0.55V-0.11V -0.51V-0.01V -1.89V-0.20V -1.56V-0.12V -1.33V-0.06V 7.51V0.46V -1.00V-0.03V -0.89V-0.03V -0.83V-0.03V -2.17V-0.30V -1.89V-0.20V -1.73V-0.12V 10.1V0.79V -1.42V-0.06V -1.26V-0.06V -1.18V-0.06V

As shown in Table 1 above, in an electrochromic display in which there is no partition, the fourth line pixels vertically are 3.18V, 3.43V, 4.0V, 10V, 5.96V, The voltages of 7.51V and 10.1V were measured, and horizontally the fourth line pixels were measured from 9.45V, 7.34V, 5.78V, 10V, 3.86V, 3.35V and 3.10V in the order from left to right pixel. .

Therefore, if voltage is applied to the fourth line pixels vertically and horizontally to generate electrochromic color at the fourth pixel horizontally and the fourth pixel vertically, only 10V electrical is applied to the fourth pixel horizontally and the fourth pixel vertically. Rather than discoloration, the pixels of the line to which the voltage is applied are also affected by the voltage more than the surrounding pixels.

In addition, the fourth line pixels perpendicular to the electrochromic display in which the partition wall of the present invention is present have voltages of 0.11V, 0.11V, 0.12V, 10V, 0.24V, 0.46V and 0.79V, and the fourth line horizontally. The pixels were measured at 0.79V, 0.46V, 0.24V, 10V, 0.12V, 0.11V and 0.11V.

Therefore, when voltage was applied to the fourth line pixel vertically and horizontally, the pixels of the line were measured almost equal to the voltage measured at the surrounding pixels, and no electrochromic change was made.

Therefore, it can be seen that the electrochromic display in which the partition is present can significantly reduce image diffusion than the electrochromic display in which the partition is not present, and the electrochromic display in which the partition is formed can be applied for information transfer. Do.

As described in detail above, the present invention can eliminate the problem of image diffusion, which is one of the most problematic crosstalk phenomena in electrochromic displays, with a barrier rib structure using photoresist, and can be applied to an information transmission display. It is effective.

Although the invention has been described in detail only with respect to specific examples, it will be apparent to those skilled in the art that various modifications and variations are possible within the spirit of the invention, and such modifications and variations belong to the appended claims.

Claims (14)

First electrode lines arranged under the first glass substrate; A second electrode line formed on the second glass substrate facing the first glass substrate so as to cross and face the first electrode lines; A plurality of pixels on the upper portions of the second electrode lines, each of which includes an electrochromic material film which discolors the intersection of the first and second electrode lines according to an electric field, and has a separation space between the respective pixels; A photoresist barrier rib formed to protrude below the first electrode lines and inserted into a space between the plurality of pixels; And a solid polymer electrolyte formed between the upper portions of the plurality of pixels and the first electrode lines. The method of claim 1, And a plurality of ion conductive thin films for preventing image diffusion between the upper portion of the plurality of pixels and the electrolyte. The method of claim 2, The ion conductive thin film is an electrochromic display, characterized in that the 0.2LiO ₂ -0.2CeO ₂ -0.6SiO ₂ single-layer thin film containing a silicon oxide (SiO ₂ ) component. The method of claim 1, The solid polymer electrolyte may be any one selected from Poly-AMPS (2-Acrylamino-2-methylpropane sulfonic acid), PEO (Poly (ethylene oxide)), Poly (VAP (Vivilacochol-phosphoric acid)) and LiCF ₃ SO ₃ Featuring an electrochromic display. The method of claim 1, The first and second electrode lines are ITO film, When the voltage of the first and second electrode lines is applied to the first electrode lines between the first electrode lines and the electrolyte, it may serve to store electrons that are moved during the oxidation and reduction reactions associated with electrochromic change. Electrochromic display, characterized in that the counter electrode is further provided. The method of claim 5, The counter electrode is an electrochromic display, characterized in that consisting of a TiO ₂ + 0.25 CeO ₂ thin film having a composition ratio of TiO ₂ and CeO ₂ 1: 0.25. Forming first electrode lines under the first glass substrate; Forming a partition wall using photoresist on the first electrode lines; Forming second electrode lines on the second glass substrate facing the first organic substrate; Forming a plurality of pixels of an electrochromic material film on top of the second electrode lines such that each pixel has a separation space therebetween; Forming a solid polymer electrolyte on the plurality of pixels; The barrier rib of the first glass substrate is inserted into the separation space of the pixels of the second glass substrate, the electrolyte contacts the second electrode lines, and the first electrode line intersects the second electrode line. 1. A method of manufacturing an electrochromic display comprising the steps of assembling a glass substrate and a second glass substrate at a constant pressure. The method of claim 7, wherein The first and second electrode lines are formed by depositing an ITO film. The method of claim 7, wherein Between the step of forming the first electrode line on the lower portion of the first glass substrate and the step of forming the partition wall using the photoresist on the upper portion of the first electrode line, When the voltage of the first and second electrode lines is applied, further comprising forming a counter electrode on the upper portion of the first electrode lines that can serve to store the electrons that are moved during the oxidation and reduction reaction associated with electrochromic The manufacturing method of the electrochromic display characterized by the above-mentioned. The method of claim 9, The counter electrode is a method of manufacturing an electrochromic display, characterized in that formed in a TiO ₂ + 0.25 CeO ₂ thin film having a composition ratio of TiO ₂ and CeO ₂ 1: 0.25. The method of claim 7, wherein Between forming a plurality of pixels made of an electrochromic material film so that each pixel has a separation space therebetween on the second electrode lines, and mounting an electrolyte on top of the plurality of pixels, And forming a plurality of ion-conducting thin films to prevent image diffusion by forming a high threshold voltage in the relationship between the plurality of pixels, which are electrochromic films, and an electrolyte. The method of claim 11, And the ion conductive thin films form a 0.2LiO ₂ -0.2CeO ₂ -0.6SiO ₂ single layer thin film containing a silicon oxide (SiO ₂ ) component. The method of claim 7, wherein The solid polymer electrolyte is equipped with any one selected from Poly-AMPS (2-Acrylamino-2-methylpropane sulfonic acid), PEO (Poly (ethylene oxide)), Poly (VAP (Vivilacochol-phosphoric acid)) and LiCF ₃ SO ₃ The manufacturing method of the electrochromic display characterized by the above-mentioned. The method of claim 7, wherein After the assembling step, Sealing around the assembled first and second glass substrates with a sealant to prevent the penetration of moisture from the outside, The electrochromic display further comprises the step of solidifying the electrolyte by irradiating UV light at 40 mJ for 200 seconds to allow safe ion exchange with the electrochromic material according to the voltage applied to the electrode line. Method of preparation.