JPS63280223A - Method for serial driving of plural ec elements - Google Patents

Abstract

PURPOSE:To contrive the coincidence of responses with each other by serially connecting and driving respective elements at the time of coloring operation, and at the time of maintaining a coloring state, driving respective elements in parallel. CONSTITUTION:An ITO electrode layer is formed on a glass substrate 1 and a groove is formed between an upper electrode 6 fetching part 6a and a lower electrode layer 2 by etching or cutting. Then, 2nd oxide coloring EC layer 2 consisting of mixture of iridium oxide and zinc oxide, a tantalum oxide layer as an ion conductive layer 4 and a tungsten oxide layer as a 1st reduction coloring EC layer 5 are successively formed and Al is vapor-deposited as an upper electrode layer 6. Finally, epoxy resin sealant 7 is applied and stuck to a sealing glass plate 8 to obtain a light quantity control element ECD. Consequently, coloring responses are made to coincide with each other.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for simultaneously driving a plurality of electrochromic devices. Hereinafter, electrochromic will be abbreviated as rEcJ.

[Conventional technology]

Electrochromism is a phenomenon in which a reversible electrolytic oxidation or reduction reaction occurs when a voltage is applied, resulting in reversible coloring. Using an EC material that exhibits this phenomenon, ECD is a light amount control element that can be colored or erased by voltage manipulation. For example, as shown in FIG.
, an ion conductive layer 4, a first EC layer 5 (reduced color forming layer), and a reflective film/metal electrode or a transparent electrode layer (upper electrode layer 6) are laminated together, and an ECD is known as an all-solid-state ECD. This ECD becomes colored when a coloring voltage obtained from a dry battery is applied between a pair of electrode layers, and disappears and returns to its original colorless and transparent state when a decoloring voltage of the opposite polarity is applied.

Therefore, if the upper electrode layer 6 is reflective or transmissive and a reflective layer is provided above, the incident light on the substrate 1 side will be absorbed by the coloring of the EC layer, so the reflected light will be attenuated. do. In other words, the reflectance can be changed electrically.

Therefore, reflective ECDs are currently being developed as anti-glare mirrors for automobiles and the like.

By the way, there are cases where it is desired to drive not only anti-glare mirrors but also a plurality of 0ECDs at the same time. In this case, considering space, number of electrical parts, cost, etc., it is preferable to use one circuit. Therefore, conventionally, when driving multiple 0ECDs at the same time, it is not possible to drive them in parallel using one common circuit. It was considered.

However, this is especially true in the case of anti-glare mirrors, as well as interior rearview mirrors and exterior side mirrors (or door mirrors).
When driving a total of 2 or 3 at the same time, each ECD
The ambient temperature is different.

In general, the coloring response of ECD becomes slower as the ambient temperature becomes lower.

[Problem that the invention seeks to solve]

Therefore, if the ambient temperatures of the ECDs differ, the responses of the ECDs will not match even if they are driven at the same time, leading to the first problem that the observer will feel uncomfortable.

In addition, in ECD, at least one of the pair of electrode layers is a transparent electrode, and as of now, as a transparent electrode material,
Snow, In, O, ITO (1n20. and SnO,
(a mixture of It is relatively slow at 5 seconds. For the same reason, if multiple ECDs with the same display area but different shapes (excluding mirror-symmetric shapes) are driven in parallel, even if the ambient temperature is the same, the responses of each ECD will not match, making observation difficult. The second problem is that the person feels uncomfortable.
There was a problem.

Therefore, when multiple ECDs are driven simultaneously by the same circuit, the objects of the present invention are: (1) to match the responses even when the ambient temperature of each ECD is different; and (2) to make the display shape consistent even when the ambient temperature of each ECD is the same. The purpose is to match the responses even when they are different.

[Means for solving problems]

As a result of intensive research, the inventors of the present invention have determined that the first and second problems can be solved by driving the ECDs in series only when the display area of each ECD is equal or almost equal. I found it.

But generally E CD! Although it has a property (memory property) of retaining the colored state even if the application of the coloring voltage is stopped after being colored, if the ECD is left in the colored state for too long without applying the coloring voltage, Discolors naturally.

Therefore, when maintaining the colored state, it is necessary to apply a coloring voltage continuously or intermittently.

However, due to factors that cannot be controlled during manufacturing, each ECD has different memory properties and different discoloration tendencies.

Therefore, if a coloring maintenance voltage is applied in series, the coloring density will vary between ECDs. Therefore, the inventors conducted further research and found that when a coloring maintenance voltage is applied in parallel,
Second, it was discovered that an autobalance effect works between each ECD, so that the appearance of memory properties can be made to match.

The present invention was made based on the first knowledge and the second knowledge, and provides the following driving method.

That is, the present invention provides a method for simultaneously driving a plurality of electrochromic elements having the same or almost equal display area using the same circuit. During coloring operation, each element is connected in series and driven to maintain the colored state. When doing so, the present invention provides a method for driving a plurality of electrochromic devices in series, characterized in that each device is driven in parallel.

In addition, the coloring operation is not only coloring to the maximum color density (,
It also includes coloring operations to intermediate densities.

[For production]

In the present invention, (1) Since the coloring operation is performed in series, the injection speed and amount of charge injected into each ECD are necessarily the same, and (1) Even if the ambient temperature of each ECD is different, ■ Even if the ambient temperature is the same but the display shape is different, the coloring response can be matched, and (2) - After mutually coloring, coloring maintenance voltages are applied in parallel, The amount of stored charge is automatically balanced between ECDs with different memory properties, and the memory properties match.

Incidentally, during the color erasing operation, the first and second problems mentioned above are not as serious as during the coloring operation, so parallel driving may be used.
If anything, series driving is preferable, and if a short circuit or a decoloring maintaining voltage is to be applied to maintain decoloring, in the latter case, parallel driving is preferable.

The laminated structure of the ECD in the present invention is not particularly limited, but the structure of the solid-state ECD includes, for example, a four-layer structure such as (1) electrode layer/EC layer/ion conductive layer/electrode layer; Examples include a five-layer structure such as electrode layer/reduction colored EC layer/ion conductive layer/reversible electrolytic oxidation layer or oxidation colored EC layer/electrode layer. In this case, one of the electrode layers must be transparent, and the electrode layer through which the colored state cannot be seen may be an opaque layer or a reflective layer.

However, the present invention is particularly suitable for driving an ECD with a large colored area.

As the material of the transparent electrode, for example, SnO, 1 nt O
, ITO, etc. are used. Such an electrode layer is generally formed by vacuum thin film forming techniques such as vacuum evaporation, ion blasting, and sputtering. (Reduction coloring property) As the EC layer, WOx, MO02, etc. are used.

As the ion conductive layer, for example, silicon oxide, tantalum oxide, titanium oxide, aluminum oxide, niobium oxide, zirconium oxide, hafnium oxide, lanthanum oxide, magnesium fluoride, etc. are used. Due to the manufacturing method, these thin films of materials are insulators for electrons, but they are insulators for protons (
It is a good conductor for Ho) and hydroxy ions (OH-). Cations are required for the coloring and decoloring reaction of the EC layer, and it is necessary to contain H′″ ions and L1° ions in the EC layer and other parts. Sometimes it is only necessary to generate H9 ions, and therefore water may be included instead of H'''ions; very little of this water is sufficient, and often even moisture that naturally enters from the atmosphere is sufficient for quenching. color.

・The EC layer and the ion conductive layer may be placed on top or bottom, and the EC layer is sandwiched between the ion conductive layer and the reversible electrolytic oxidation layer (or oxidation-colored EC layer or catalyst). layer) may be provided.

Such layers include, for example, iridium oxide or hydroxide, nickel, chromium, vanadium, ruthenium, rhodium, etc. These substances are dispersed in the ionically conductive layer or the transparent electrode. They may contain these constituent substances, or they may be dispersed and contained.

The opaque electrode layer may also serve as a reflective layer, and for example, metals such as gold, silver, aluminum, chromium, tin, zinc, nickel, ruthenium, rhodium, and stainless steel are used.

〔Example〕

A glass substrate (1) of length B cta A groove was formed between the electrode layer (2) and the electrode layer (2). This formed a lead-out portion (6a), a lower electrode layer (2), and a lead-out portion of the lower electrode that continued therefrom.

Note that these patterns may be directly formed by depositing ITO using a mask.

Next, a second EC layer (3) with oxidation coloring properties made of a mixture of iridium oxide and tin oxide, a tantalum oxide layer as an ion conductive layer (4), and a tungsten oxide layer as the first EC layer (5) with reduction coloring properties are formed. formed in sequence.

Next, A2 was deposited as the upper electrode layer (6).

At this time Aj! One end is brought into contact with the take-out portion (6)a already formed on the substrate (1).

Finally, apply the epoxy resin sealant (7) to the sealing glass plate (8).
) was applied to the ECD, and the epoxy resin was cured by leaving it to stand, thereby producing the ECD shown in FIG. 2. FIG. 2 is partially deformed and does not have accurate dimensional ratios.

In this ECD, since the upper electrode layer (6) is Affi and also serves as a reflective layer, the light incident from the substrate 1 side is reflected by the upper electrode layer (6), so the reflectance R is maintained in the decolorized state. When measured, R=60%. However, in the colored state, the reflected light passes through the first EC layer (5) and the second EC layer (3) twice on the way, so when those EC layers are in the colored state, it is absorbed and the amount of reflected light decreases. However, as a result, the anti-load resistance R also decreases.

In fact, when a DC coloring voltage Vc-+1.35V was applied from the drive power source (Su) to the 20ECD, the R-15% was reduced.

When the two 0ECDs (10) were assembled into a circuit as shown in Figure 1, the interlocking switch (9) was turned to the series (A) side, and a voltage of +2.7V (coloring voltage) was applied in the coloring direction. The reflectance of both ECDs decreased from 60% to 15% after 5 seconds.

Next, in this state, the interlocking switch (9) was turned to the parallel (B) side, a coloring maintenance voltage of +1.2 V was applied, and it was left for 24 hours, but no change in reflectance was observed in either case. Note that the drive power supply (Su) is ON.

It is shown in FIG. 1 that it is possible to freely select OFF, voltage direction, and voltage value.

Also, keep one ECD (10) at room temperature and the other at -20°.
When held at C and driven in the same way, these two EC
No difference in response was observed for D(10).

[Comparative example]

When one ECD (10) was held at room temperature and the other at -20°C, the interlocking switch (9) was turned to the parallel side, and a DC voltage of +1.35 V was applied in the coloring direction, reflections were observed throughout. The former took 5 seconds and the latter 10 seconds for the rate to drop to 15%. The coloring response is two times different.

Also, turn the interlock switch (9) to the series side,
When a DC voltage of -1,35V was applied in the decoloring direction for 5 seconds at -20°C and 2 seconds at room temperature, it took 2 seconds for the former (room temperature) and 2 seconds for the latter (- 20°C)5
It took seconds.

〔Effect of the invention〕

As described above, according to the present invention, since the coloring responses match, the observer does not feel discomfort, and even if the memory properties of each ECD are different when maintaining coloring, the appearance is the same. Looks good.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an ECD drive circuit used in an embodiment of the present invention. FIG. 2 is a schematic vertical sectional view of the ECD used in the same example. [Explanation of symbols of main parts] 1...Substrate 2...Lower electrode layer (transparent electrode) 3...
Oxidation color-forming second EC layer 4...Ion conductive layer 5...Reduction color-forming first EC layer 6...
Upper electrode 1m (reflective electrode) 7...Sealant 8...Glass plate for sealing 9...Interlocking switch

Claims (1)

[Claims] In a method for simultaneously driving a plurality of electrochromic elements having equal or substantially equal display areas using the same circuit, each element is connected in series and driven during a coloring operation, and the colored state is A method for driving multiple electrochromic devices in series, characterized in that each device is driven in parallel when maintaining the same.