JP2753275B2 - Liquid crystal display - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid crystal display, and more particularly to a reflector and an operation power supply thereof.

[Problems to be Solved by Conventional Techniques and Inventions] In our daily lives, a liquid crystal display (hereinafter, referred to as an LCD) is a battery-powered, portable and familiar display.
That. ). LCD is thin, lightweight, low power consumption,
Watches, personal computers,
It is widely used in various application fields such as word processors and LCD TVs, and it is expected that the range of use will further expand in the future.

However, the biggest problem with LCDs is visibility, especially the dependence on viewing angle. In other words, there is an angle that cannot be seen well due to the reflection of light.
It is necessary to provide a reflecting plate such as aluminum foil on the back of the device.
In addition, instead of an aluminum foil reflector, a method has been adopted in which a fluorescent lamp or the like is inserted on the back to eliminate unevenness in light (a so-called backlight method for LCDs such as word processors). However, this backlight method is lightweight. It is not suitable for battery-powered LCD because it is out of the demand for low cost.

On the other hand, dry batteries, button batteries, and the like are used as batteries for driving the LCD, but a battery box must be provided for these batteries, and there has been a limit to thinning and miniaturizing the device. Further, such a battery may cause liquid leakage or the like.

The present invention has been made in order to solve the above-mentioned conventional problems. In a battery-driven liquid crystal display, a battery storage box is not required, and the liquid crystal display and the entire device are made very thin and lightweight, and have high safety. It is an object to provide a liquid crystal display driven by a battery.

[Means for Solving the Problems] A liquid crystal display of the present invention that achieves the above object is a battery-driven liquid crystal display laminated on a driving circuit board, and uses a paper battery that also serves as a power supply as a reflector. The paper battery is folded such that a part of one of the positive electrode and the negative electrode formed on both sides thereof is on the same plane as the other, and both electrodes on the same plane are each a pair of the circuit board. It is characterized by being arranged so as to face the power supply terminal.

Here, the battery paper battery also serving as the reflector is preferably a current collecting layer of the positive electrode, an active material layer of the positive electrode, a polymer solid electrolyte layer,
It is formed by sequentially laminating aluminum foil layers.

As a substance forming the current collecting layer of the positive electrode, mainly carbon or a metal oxide is used. In this case, carbon in which carbon particles, carbon fibers or graphite are dispersed in a polymer compound is used. Metal oxides include ITO (indium tin oxide), indium oxide,
Tin oxide, mercury oxide, copper oxide, lead dioxide and the like,
These may be used alone or dispersed in a polymer compound.

As a polymer compound for dispersing carbon or metal oxide, urethane resin, bratyl resin, acrylic resin, vinyl chloride / vinyl acetate copolymer, polycarbonate resin, AB
S resin, Teflon resin, natural rubber, polyester resin,
Alkyd resin, polyamide resin, polyimide resin, epoxy resin, phenol resin, melamine resin, styrene resin, acetal resin, nylon resin, polyolefin resin, cellulose resin, polyvinyl alcohol, polypropylene, polyacrylamide, and the like.

The surface resistance of the current collecting layer of the positive electrode is preferably not more than 10 ³ Ωcm ⁻¹ , more preferably not more than 5 × 10 ² Ωcm ⁻¹ by a four-terminal method in order to enhance the current collection effect.

The active material layer of the positive electrode is composed of a polymer compound in which manganese dioxide is dispersed.

This high molecular compound is a urethane resin, a butyral resin, an acrylic resin, a vinyl chloride / vinyl acetate copolymer, a polycarbonate resin, like the high molecular compound used for the current collecting layer of the positive electrode.
ABS resin, Teflon resin, natural rubber, polyester resin, alkyd resin, polyamide resin, polyimide resin,
Epoxy resin, phenol resin, melamine resin, styrene resin, acetal resin, nylon resin, polyolefin resin, cellulose resin, polyvinyl alcohol,
Polypropylene, polyacrylamide and the like are used. Since manganese dioxide is the active material of the positive electrode,
From the viewpoint of battery capacity and practical physical properties, it is desirable that the content be 50 parts by weight or more and 80 parts by weight or less based on the total amount of the active material layer of the positive electrode.

The polymer solid electrolyte layer includes a non-crystalline polymer compound and an alkali metal salt.

Amorphous polymer compounds are those whose glass transition point is lower than room temperature and under vigorous molecular motion at room temperature, such as polyethylene oxide (PEO), polymethoxy polyethylene glycol methacrylate, polyvinyl pyridine, and polysiloxane. , Polypropylene oxide, segmented polyurethane, polyurethane urea,
Examples include polyphosphazene, cellulose, polystyrene, and polypeptide. In particular, polymers of monoester methacrylates of the formula I In the case of using, a battery having a high energy density can be obtained.

Further, as the alkali metal salt used in the polymer solid electrolyte, a lithium salt is preferable, and LiClO ₄ , LiBr, LiSC
N, LiCl, LiBF ₄ , LiPF _{6 and the} like. The amount of the alkali metal salt in the polymer solid electrolyte varies depending on the polymer compound used, and is preferably 1 to 99 parts by weight, more preferably 1 to 30 parts by weight of the whole polymer solid electrolyte layer.

The aluminum foil layer serves as a negative electrode and also serves as a reflector of a liquid crystal display. The thickness of the aluminum foil layer is preferably 10 μm or more and 50 μm in handling, more preferably 30 μm.
It is desirably at least 50 μm.

A paper battery was prepared by mixing each layer-forming substance with an appropriate solvent and dispersant as a coating solution, sequentially applying and drying the support 1 as shown in FIG. 1, and further laminating an aluminum foil layer. The laminate 6 can be formed by peeling the laminate 6 from the support 1. At this time, the current collecting layer 2 of the positive electrode and the active material layer 3 of the positive electrode are sequentially coated and dried on the support 1 as a coating liquid obtained by mixing a layer forming substance with water, alcohol, other organic solvent and dispersant. It forms by doing.

The polymer solid electrolyte layer 4 is formed by applying a mixture of a non-crystalline polymer compound and an alkali metal salt with an appropriate solvent on the active material layer of the positive electrode and drying the mixture.

Further, after laminating the aluminum foil layer 5 on the polymer solid electrolyte layer 4, the laminate 6 is peeled off from the support 1 to obtain a paper battery.

Each of the positive electrode current collector layer 2, the positive electrode active material layer 3, and the solid polymer electrolyte layer 4 can have a dry film thickness of not more than 20 μm, and can have a dry film thickness of about 1 μm. In addition, the thickness of the entire battery can be reduced to 0.01 mm.

The paper battery configured as described above can be used by cutting a required area according to a required capacity with scissors, a cutter, or the like, and a necessary voltage can be obtained by overlapping according to a required voltage.

As shown in FIG. 2, for example, a liquid crystal display (LCD) is provided with a glass plate 11 having a deflector 10 adhered to one surface and a molecular alignment layer 12 and a transparent electrode 13 on the other surface. , 11 'are adhered to each other with a peripheral sealing material 14 so that the electrodes 13 are opposed to each other, and a liquid crystal 15 is sealed between the two electrodes 13. The aluminum foil layer 5 of the voltage paper battery 16 is bonded with an appropriate adhesive or adhered without an adhesive.

FIG. 3 shows an embodiment of a liquid crystal timepiece to which the LCD of the present invention is applied.
Further, the driving circuit board 21 is stacked and housed in the cases 30 and 31. Here, the LCD 20 has a structure as shown in FIG. 2, and has a connection terminal 20a at an end. The drive circuit board 21 includes a drive IC 23 and a conductor pattern 24. The conductor pattern 24 includes a connection terminal 22 connected to the connection terminal 20a of the LCD 20, and power supply terminals 25 and 26. or,
In the paper battery 16, the aluminum foil layer 5 is in close contact with the back side of the LCD 20 and acts as a reflector of the LCD 20, and a part of the end of the aluminum foil layer is folded back to the positive current collecting layer 2 side. 21 is opposed to one power supply terminal 26. on the other hand,
The current collecting layer 2 of the positive electrode faces another power supply terminal 25. An insulating spacer 40 having holes 45 and 46 corresponding to the terminals 25 and 26 is interposed between the circuit board 21 and the paper battery 16 so that portions other than the terminals are not short-circuited.

As described above, since the reflective plate and the battery for the battery are used as the reflective plate of the LCD, the case 31 does not need the storage space for the battery which was conventionally required, and the liquid crystal display device itself is very thin. It is possible to reduce the weight.

[Example] Example 1 A polyester film (thickness: 50μ) was used as the insulator 1, and a coating solution having the following formulation was applied using a Mayer bar so that the dry film thickness became 20μ, and dried at 100 ° C for 5 minutes. Thus, the current collecting layer 2 of the positive electrode was obtained.

Conductive carbon black (product of Vulcan XC-72 Cabot) 6 parts by weight Dispersant (product of Roma PW Sannopco) 1 part by weight Water 81 parts by weight Water-based polyurethane resin (product of Neoretz R966 Polyvinyl Chemicals) 12 parts by weight Formulation of the above composition The product was dispersed and mixed by a ball mill for 24 hours to obtain a coating solution.

When the surface resistance of the current collecting layer 2 of the positive electrode was 15 cm × 15 cm, it was 5 × 10 ² Ωcm ⁻¹ by the four-terminal method.

On the current-collecting layer 2 of the positive electrode, a coating solution having the following formulation was applied using a Mayer bar so as to have a dry film thickness of 20 μm, and dried at 100 ° C. for 5 minutes to obtain a positive electrode active material layer 3.

Manganese dioxide 24 parts by weight Dispersant (Roma PW Sannopco) 1 part by weight Isopropyl alcohol 5 parts by weight Water 60 parts by weight Water-based polyurethane resin (Permarin UA500 Sanyo Chemical Industries, Ltd.) 10 parts by weight The mixture was mixed for 24 hours to obtain a coating solution.

A mixture of a monoester methacrylate polymer of the formula I (where n = 4) and LiClO ₄ is uniformly applied on the positive electrode active material layer 3, dried, and dried to obtain a polymer solid electrolyte layer. And 4.

First, monoester methacrylate was polymerized as follows.

Monoester methacrylate (NK
The solution in which the ester M-40G (Shin-Nakamura Chemical Co., Ltd.) was dissolved was stirred in a polymerization tube under a nitrogen stream.

Thereafter, 1 g of azoisobutylnitrile was added to 10 g of methylene chloride.
The solution dissolved in g was added dropwise, and the mixture was stirred at 50 ° C. for 45 minutes.

After the reaction solution was allowed to cool at room temperature, it was added to 500 ml of methanol with stirring to precipitate the desired polymer. The polymer was redissolved in methylene chloride, purified by repeating reprecipitation with methanol again, and dried at 70 ° C. in vacuo to obtain a purified polymer.

The viscosity of a 70% by weight solution of this polymer in methylene chloride was 500 cp (25 ° C.) in a B-type viscosity form.

25.5 g of the polymer and 4.5 g of LiClO ₄ , 70 g of methyl ethyl ketone
Was uniformly mixed so as to have a dry film thickness of 5 μm as a coating solution, and dried at 100 ° C. for 2 minutes to obtain a polymer solid electrolyte layer 4.

An aluminum foil having a thickness of 30 μm (manufactured by Toyo Aluminum Co., Ltd.) was laminated on the polymer solid electrolyte layer 4 at a laminating pressure of 0.5 kgf / cm ² .

As described above, the positive electrode current collecting layer 2, the positive electrode active material layer 3, the polymer solid electrolyte layer 4, and the aluminum foil layer 5 sequentially laminated on the insulator 1 are peeled off from the insulator 1 to form a 0.075 mm thick. I got a paper battery.

 FIG. 3 shows the discharge characteristics of the paper battery.

 The capacity at this time is calculated as follows.

Size 6 cm × 12 cm Capacity (Ah) 10 mAh (Calculated based on the time when the super power drops to 0.5 V) The paper battery was cut into 2 cm × 6 cm with a cutter, and three sheets of the same size were prepared.

An LCD watch (Kaho Radio Co., Ltd., Chibide Clock HT-22,
External dimensions 57 x H32 x D11m / m, liquid crystal display size 4.7cm x 2.1c
m, driven by a button-type battery (LR43) and used as a reflector, the battery operated for one year as well as a liquid crystal watch driven by a conventional button-type battery (LR43). The contrast intensity of the liquid crystal display visually observed was almost the same.

Further, when the reflection plate / battery is used for the liquid crystal watch,
The thickness could be reduced from 11m / m to 7m / m. In addition, the weight was reduced from 19.98g to 14.19g.

Example 2 The same paper battery as in Example 1 was cut into a piece of 10 cm × 4.5 cm with a cutter, and three pieces of the same size were prepared. A large liquid crystal watch (Omron Quartz CQ70, manufactured by Tateishi Electric Co., Ltd.)
0, external dimensions W143 × H80 × D14m / m, liquid crystal display size 10cm ×
When used as a reflector and a battery (4.5 cm, powered by AAA batteries), it operated for one year as much as a liquid crystal watch driven by conventional AAA batteries. The contrast intensity of the liquid crystal display visually observed was almost the same.

Further, when the reflection plate / battery is used for the liquid crystal watch,
The thickness could be reduced from 14m / m to 6m / m. In addition, the weight was reduced from 134.95g to 41.0g.

[Effects of the Invention] In the battery-driven liquid crystal display of the present invention, since the reflector of the liquid crystal display also serves as a battery, there is no need for a battery storage space, and the liquid crystal display and the entire device are extremely thin and lightweight. It is possible and extremely valuable in industry.

In addition, since the battery-driven liquid crystal display of the present invention uses a paper battery using a polymer solid electrolyte as a battery, there is no danger of liquid leakage and the safety is high. In addition, since the structure in which the electrode and the electrolyte layer are sequentially formed, the manufacturing is easy, and therefore, the manufacturing can be performed at low cost.

Further, replacement of the reflector / battery can be easily performed simply by peeling off the rear glass substrate of the liquid crystal display and attaching a new reflector / battery.

[Brief description of the drawings]

FIG. 1 is a view showing the structure of one embodiment of a paper battery applied to the liquid crystal display of the present invention, FIG. 2 is a cross-sectional view of the structure of one embodiment of the liquid crystal display of the present invention, and FIG. FIG. 4 is an exploded perspective view of an embodiment of a liquid crystal timepiece to which the liquid crystal display of the present invention is applied, and FIG. DESCRIPTION OF SYMBOLS 1 ... Support body 2 ... Current collecting layer of positive electrode 3 ... Active material layer of positive electrode 4 ... Solid polymer electrolyte layer 5 ... Aluminum foil layer 16 ... Paper battery 20 ... Liquid crystal display

Claims (3)

(57) [Claims] 1. A liquid crystal display driven by a battery laminated on a driving circuit board, comprising a paper battery serving also as a power supply as a reflection plate, wherein the paper battery has one of a positive electrode and a negative electrode formed on both surfaces thereof. A liquid crystal, wherein a part of the liquid crystal is folded so as to be on the same plane as the other, and both electrodes on the same plane are respectively arranged so as to face a pair of power supply terminals of the circuit board. display. 2. The paper battery according to claim 1, wherein the paper battery is a thin primary battery in which a current collecting layer of a positive electrode, an active material layer of a positive electrode, a solid polymer electrolyte layer, and an aluminum foil layer are sequentially laminated. LCD display. 3. The liquid crystal display according to claim 2, wherein said aluminum foil serves as a reflector of the liquid crystal display.