JPH11242198A - Stamping material for liquid crystal board - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an image in short contact time as well as to form a sharp image, and to prevent scratching of a liquid crystal board by constituting a stamping material of a resin formed body containing a plasticizer and having specified volume resistivity. SOLUTION: This stamping material 1 for a liquid crystal board consists of a resin formed body containing a plasticizer and having 1×10<7> to 1×10<12> Ω.cm volume resistivity. The resin formed body preferably consists of a resin selected from vinyl chloride resin and/or vinyl chloride-vinyl acetate copolymer resin and contains a plasticizer in the resin. The amt. of the plasticizer is preferably 15 to 50 wt.%. As for the plasticizer, one or more kinds selected from 2,2,4-trimethyl-1,3-pentanediol diisobutylate, phthalic acid esters and dibasic acid esters are preferably used together. The resin formed body is produced by dispersing the plasticizer, heating to dissolve, and then formed into a stamp shape. The plasticizer is uniformly blended in the resin to give flexibility to the resin formed body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a stamp material for a liquid crystal board. More specifically, the present invention relates to a stamp material for a liquid crystal board which forms a desired image by applying or removing an electrostatic charge from the outside.

[0002]

2. Description of the Related Art Conventionally, a stamp material capable of forming an image on a liquid crystal board on which an image is formed by applying or removing an electrostatic charge from the outside is described in Japanese Patent Application Laid-Open No. 5-281530. Examples of the material used for the conventional stamp material include various metals, metal oxides, conductive polymers, graphite, and carbon fibers, and the stamp material has a volume resistivity of 10 ¹² Ω · cm or less. It is disclosed that a high contrast image can be formed by smoothly applying or removing an electrostatic charge to the display surface of a liquid crystal board. However, as a necessary condition for the stamp material, there is a need to form a clear image with excellent adhesion to the display surface,
Therefore, those having flexibility are preferably used. or,
In order to obtain a stamp material having flexibility and a low volume resistivity, for example, as a conductive powder, a metal powder dispersed in rubber can be exemplified.
Uniformly dispersing the metal powder is difficult to manufacture, and furthermore, the display surface may be finely scratched due to contact with the metal powder, which may cause problems such as impairing the performance and quality of the liquid crystal board.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to solve the drawbacks of a stamp material that can be used for a conventional liquid crystal board, that is, to include a plasticizer and
By using a stamp material composed of a resin molded product having a specific volume resistivity, an image can be formed in a short contact time, and a clear printed image can be formed because of excellent flexibility, and It is an object of the present invention to provide a stamp material that does not damage a liquid crystal board.

[0004]

According to the present invention, an electrostatic charge is externally applied to a display surface of a liquid crystal board provided with a conductive layer and a liquid crystal dispersed polymer layer in which a liquid crystal is finely dispersed in a polymer matrix on the conductive layer. Alternatively, a stamp material capable of forming or erasing an image by changing the light scattering state of the liquid crystal by removing the stamp material, wherein the stamp material contains a plasticizer and has a volume resistivity of 1 × 10 ⁷ to 1 ×. A stamp material for liquid crystal boards, which is a resin molded product of 10 ¹² Ω · cm, is required. Furthermore, the resin molded product contains a plasticizer in a resin selected from a vinyl chloride resin and / or a vinyl chloride-vinyl acetate copolymer resin, and the plasticizer is contained in an amount of 15 to 50% by weight.
Wherein the plasticizer is 2,2,4-trimethyl-
It is a requirement that the plasticizer be a combination of one or more selected from 1,3-pentanediol diisobutyrate, phthalate esters, and dibasic ester esters.

[0005] The resin molded product used as the stamp material is obtained by dispersing a plasticizer in the resin, heating the resin to make it compatible with each other, and appropriately molding the resin into a stamp shape. Any of a polymer, a grafted product, and a mixture may be used. Examples of the resin include a vinyl chloride resin, a copolymer containing a vinyl chloride resin such as a vinyl chloride-vinyl acetate copolymer resin, and a cellulosic resin such as acetyl cellulose.In order to obtain a highly flexible stamp material, A vinyl chloride resin, a vinyl chloride-vinyl acetate copolymer resin, or a mixture thereof is suitably used.

[0006] The plasticizer is uniformly blended in the resin to impart flexibility to the resin molded product. Examples thereof include triethyl phosphate, tributoxyethyl phosphate, tri (chloroethyl) phosphate, and phosphoric acid. Phosphate plasticizers such as tributyl, tri (2-ethylhexyl) phosphate, octyl diphenyl phosphate, triphenyl phosphate, tri (isopropylphenyl) phosphate, tricresyl phosphate, cresyl diphenyl phosphate, etc., and dimethyl phthalate ,
Diethyl phthalate, dibutyl phthalate, diheptyl phthalate, di-n-octyl phthalate, di (2-ethylhexyl) phthalate, diisononyl phthalate, octyl decyl phthalate, diisodecyl phthalate, ditridecyl phthalate, dicyclohexyl phthalate, phthalate Phthalate plasticizers such as butyl benzylate, di (2-butoxyethyl) phthalate, dibutyl adipate, di-n-adipate
-Adipate ester plasticizers such as hexyl, di (2-ethylhexyl) adipate, diisononyl adipate, diisodecyl adipate, dibutyl glycol adipate, di (2-ethylhexyl) azelate, dihexyl azelate, diisooctyl azelate, etc. Azelaic acid ester plasticizers, sebacic acid ester plasticizers such as dibutyl sebacate, di (2-ethylhexyl) sebacate, methylphthalylethyl glycolate, ethylphthalylethyl glycolate, butylphthalylbutyl glycolate, etc. Glycolic acid ester plasticizers, ricinoleic acid ester plasticizers such as methyl acetyl ricinoleate and butyl acetyl ricinoleate, triethyl citrate, acetyl triethyl citrate, and acetyl tributyl citrate. Phosphate ester plasticizers, other,
2,2,4-trimethyl-1,3-pentanediol diisobutyrate, butyl oleate, glycerin monooleate, diethylene glycol dibenzoate, triethylene glycol di (2-ethylbutyrate), trimellitate plastic Agent, polyester plasticizer, epoxy plasticizer, polyester plasticizer,
Chlorinated paraffin, chlorinated biphenyl and the like can be mentioned.
Further, the plasticizer imparts flexibility to the resin molded product, reduces the resistivity of the resin having a relatively high volume resistivity, and easily forms an image on the display screen of the liquid crystal board with a short contact time. It is also used for the purpose of forming. Therefore, among the above plasticizers, dimethyl phthalate, diethyl phthalate, dibutyl phthalate, di (2-butoxyethyl) phthalate, dibutyl adipate, di-n-hexyl adipate, di (2-ethylhexyl) adipate Didiisononyl adipate, diisoisodecyl adipate, dibutyl glycol adipate, di (2-ethylhexyl) azelate, dibutyl sebacate, di (2-ethylhexyl) sebacate, 2,2,4-trimethyl-1,3- A plasticizer such as pentanediol diisobutyrate is suitably used to obtain flexibility and a desired volume resistivity. or,
The plasticizer is preferably contained in the resin in an amount of 15 to 50% by weight. If the amount is less than 15% by weight, desired flexibility and volume resistivity are hardly obtained. If the amount exceeds 50% by weight, a plasticizer is transferred to the liquid crystal board, and a clear image may be formed and image erasability may be impaired.

The stamp material formed as described above has a volume resistivity of 1 × 10 ⁷ to 1 × 10 ¹² Ω · cm. As a device for measuring volume resistivity, DC voltage 50
0V dry cell or accumulator, or a rectified AC power source that maintains a constant DC voltage, a standard resistor of 1M ohm manganin or a standard resistor machine with an accuracy equal to or better than that, for adjusting the deflection and measuring range of the galvanometer , Consisting of a precision all-purpose shunt meter, a suitably insulated and protected switch,
The resin molded product used as the test piece is 100 mm in diameter and 2 mm in thickness
What was formed into a disk of the above. The measurement method is as follows. The thickness of the test piece is accurately measured to 0.01 mm with the outer micrometer specified in JIS B7502, and the conductive rubber is crimped to the electrode. The outer diameter of the inner circle was measured with a vernier caliper to 0.02 mm), and charged for 1 minute to measure the volume resistance. The volume resistivity was calculated from the obtained value of the volume resistivity by the following equation. ^{_{ρ v = (πd 2 / 4t}} ) × R v ρ v: volume resistivity (MΩ · cm) d: outer diameter of the inner circle of the surface electrodes (cm) t: thickness of the test piece (cm) R _v: volume resistance

[0008] The shape of the stamp material is not particularly limited, and examples thereof include those formed in an arbitrary outer shape and those provided with an appropriate convex or concave image. An image may be formed on a curved surface of a roller-shaped stamp, and the roller may be rotated to form a plurality of images or a continuous image. Examples of the shape of the image include letters, numbers, symbols, various geometric patterns, and designs.

The liquid crystal board is capable of forming or erasing an image by applying or removing an electrostatic charge on a screen, and applies an electrostatic charge to a liquid crystal display element having a liquid crystal dispersed polymer layer provided on a conductive layer. And a power source for generating a surface potential on the screen. In order to form an image on the liquid crystal board, one terminal of a power supply is connected to a conductive layer of a liquid crystal display element, the other terminal is connected to a stamp material, and the stamp material is brought into contact with a display, By generating a surface potential between the surface and the conductive layer, the liquid crystal molecules in the liquid crystal dispersed polymer layer are aligned in the direction of the electric field, and the image is formed by the difference in contrast between the aligned portions of the liquid crystal molecules and the unaligned portions. Is visually recognized. When erasing the image, an erasing material electrically connected to the conductive layer is brought into contact with the portion of the liquid crystal display element where the image is formed to bring the image and the conductive layer to the same potential, thereby reducing the electrostatic charge. Remove and erase. In the liquid crystal board, a human body can be interposed in an electrical connection between one terminal of the power supply and the stamp material.

[0010] Even if the conductive layer is made of a metal or a material having poor conductivity, the surface resistivity of a film formed of a highly conductive material such as a metal or a conductive plastic is 10 ⁷ Ω / □ or less. Layer. As the liquid crystal dispersed polymer layer provided on the conductive layer, a liquid crystal in which liquid crystals are dispersed in an independent droplet form in a polymer is preferably used, and
It is preferable that the volume resistivity is 10 ¹³ Ω · cm (20 ° C., 90% RH) or less. The polymer may be any polymer that is hardly compatible with the liquid crystal, and the material is not particularly limited. Further, by including a crosslinking agent in the polymer, the polymer and the liquid crystal can be made hardly compatible. As the liquid crystal, a nematic liquid crystal having a positive dielectric anisotropy is preferably used, and a liquid crystal phase of -10 to 100 ° C.
And a birefringence (Δn) of 0.2 or more is preferably used. Examples of the method of dispersing the liquid crystal in the polymer include a method of microencapsulating the liquid crystal and dispersing it in the polymer, a polymerization phase separation method, a melt cooling phase separation method, a polymer-liquid crystal common solvent evaporation phase separation method, and the like. . A transparent insulator layer may be provided on the liquid crystal dispersed polymer layer to prevent decay of electrostatic charge and improve image preservability, and to physically protect the liquid crystal dispersed polymer layer. The transparent insulator layer has a volume resistivity of 1
This is a layer formed of a polymer having a resistance of 0 ¹³ Ω · cm (20 ° C., 90% RH) or higher. As the power source, a dry battery is suitably used in terms of versatility, and if necessary, a switch,
An electric circuit to which a transistor, a resistor, and the like are added is incorporated. The liquid crystal display element produced as described above is appropriately fitted into a frame to form a liquid crystal board.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The stamp material for a liquid crystal board of the present invention is applied to a display screen of a liquid crystal board to apply or remove an electrostatic charge, thereby making it possible to use hiragana, katakana, romaji, numerals,
It forms images of stars, maps, flora and fauna, food, vehicles, buildings, roads, railway tracks, etc.

[0012]

Examples are shown below. The parts in the examples are parts by weight. Example 1 (see FIGS. 1 and 2) 50 parts of vinyl chloride resin (trade name: Zeon 121, manufactured by Zeon Corporation), di (2-ethylhexyl) phthalate
[Trade name: Sansosizer DOP, manufactured by Shin Nippon Rika Co., Ltd.] A plastic sol composed of 50 parts of a dispersion was formed into a cylindrical shape having a diameter of 6 cm and a height of 2 cm, and a diameter of 2 cm at the center upper part of the cylinder. Place at 140 ° C. for 10
After heating for 1 minute, stamp material 1 was obtained. When the volume resistivity of the stamp material was measured, it was 3.7 × 10 ⁸ Ω · cm.
(23 ° C., 50% RH).

A liquid crystal-dispersed polymer solution was applied onto a conductive layer on which aluminum was vapor-deposited on the PET film, and dried to form a liquid crystal-dispersed polymer layer. The display body is fitted into the frame body 22, and one terminal of the power supply housed in the frame body 22 is connected to the conductive layer, and the other terminal is exposed to a part of the frame body 22 to form the contact portion 23. The liquid crystal board 2 was formed.

Holding the grip 11 of the stamp material 1 with one hand and pressing the image forming portion 12 of the stamp material 1 on the display 21 while touching the contact portion of the liquid crystal board with the other hand, the display 21 A surface potential was generated at a portion where the image forming portion 12 was in contact, and the liquid crystal in the liquid crystal dispersed polymer layer was oriented by an electrostatic field, whereby a circular image 3 could be formed. The circular image 3 was formed when the image forming portion of the stamp material was brought into contact with the display body of the liquid crystal board in a short contact time, and a clear circular image was obtained because of excellent flexibility. .

Example 2 (see FIG. 3) 56 parts of vinyl chloride resin (trade name: Zeon 131, manufactured by Zeon Corporation), di (2-ethylhexyl) adipate [trade name: Sansosizer DOA, Shin Nippon Rika Co., Ltd.] A stamp material 1 was obtained by placing a plastisol comprising 44 parts of a dispersion in a mold having a height of 6 cm and a cross section of a heart shape and heating at 140 ° C. for 10 minutes. When the volume resistivity of the stamp material was measured, it was 2.8 × 1
^{0 7 Ω · cm (23 ℃} , RH 50%) was.

While holding the stamp material 1 with one hand and touching the same contact portion of the liquid crystal board as in the first embodiment with the other hand,
When one end face of the stamp material is pressed onto the display body 21,
A surface potential was generated at a portion where the display body 21 and one end face of the stamp material were in contact with each other, and the liquid crystal in the liquid crystal dispersed polymer layer was oriented by an electrostatic field, whereby a heart-shaped imprint 3 could be formed. The heart-shaped image 3 is formed by the image forming portion of the stamp material contacting the display body of the liquid crystal board in a short contact time, and a clear heart-shaped image is obtained because of its excellent flexibility. Was done.

Example 3 63 parts of vinyl chloride resin (trade name: Zeon 25, manufactured by Nippon Zeon Co., Ltd.), 2,2,4-trimethyl-1,3-pentanediol diisobutyrate (trade name: Kyowanol D, A plastisol consisting of 37 parts of a dispersion (manufactured by Kyowa Hakko Kogyo Co., Ltd.) was placed in a mold having a cylindrical shape having a diameter of 3 cm and a height of 5 cm, and heated at 140 ° C. for 10 minutes to obtain a stamp material. One end face of the stamp material was cut to provide an image forming portion for the letter “A” having a convex shape. When the volume resistivity of the stamp material was measured, it was 5.7 × 10 ⁷ Ω.
Cm (23 ° C., 50% RH).

Holding the stamp material with one hand and pressing the image forming portion of the stamp material on the display while touching the contact portion of the liquid crystal board with the other hand, the surface of the stamp member contacts the image forming portion. An electric potential was generated, and the liquid crystal in the liquid crystal dispersed polymer layer was oriented by an electrostatic field, whereby an image of the letter "A" could be formed. The image of the letter "A" is formed by the image forming portion of the stamp material contacting the display body of the liquid crystal board in a short contact time, and has a sharp "A" because of its excellent flexibility. An image was obtained.

Example 4 70 parts of vinyl chloride resin (trade name: ZEST PQHB, manufactured by Shin Daiichi Vinyl Co., Ltd.), di (2-butoxyethyl phthalate) [trade name: Plasizer M-170, Kyowa Hakko Kogyo Co., Ltd.] Plastisol consisting of 30 parts of a dispersion is projected on each side of a regular hexahedron having a side of 2 cm, and each of the figures has a convex shape of "1", "2", "3", "4", "5", "6". At 140 ° C. in a mold configured to form
Heated for a minute to obtain a stamp material. When the volume resistivity of the stamp material was measured, it was 1.0 × 10 ⁹ Ω · cm.

While holding the stamp material with one hand and touching the contact portion of the liquid crystal board with the other hand, "1"
When the surface on which the number is formed is pressed down on the display, a surface potential is generated in a portion where the display and the image forming portion are in contact, and the liquid crystal in the liquid crystal dispersed polymer layer is oriented by an electrostatic field,
An imprint of the number "1" could be formed. In addition, when the stamp material was changed and the surface on which the number "2" was formed was pressed on the display body, an image of the number "2" could be formed. Further, by holding the stamp material and pressing it down on the display body, it was possible to form an image having a number of 3 to 6. The imprints of the numbers 1 to 6 are formed when the image forming portion of the stamp material comes into contact with the display body of the liquid crystal board in a short contact time, and have excellent flexibility because of excellent flexibility. A numerical image was obtained.

Example 5 70 parts of a vinyl chloride resin (trade name: Zeon 121, manufactured by Nippon Zeon Co., Ltd.) and a plasticizer (trade name: Plasizer M-
170, manufactured by Kyowa Hakko Kogyo Co., Ltd.) A plastisol composed of 30 parts of a dispersion can be formed so that concave “O”, “X”, and “△” symbols can be formed on the side surface of a cylinder having a diameter of 3 cm and a height of 2 cm. It was placed in a mold and heated at 140 ° C. for 10 minutes to obtain a stamp material. When the volume resistivity of the stamp material was measured, it was 1.0 × 10 ⁹ Ω · cm. A hole communicating from the circular central portion at one end to the circular central portion at the other end of the stamp material was provided, and both ends of a U-shaped metal member were bent and inserted into the hole to obtain a rotary stamp material.

Holding the metal member of the stamp material with one hand,
When the stamp material is rotated on the display while touching the contact portion of the liquid crystal board with the other hand, a surface potential is generated at the portion where the display and the image forming portion are in contact, and the liquid crystal in the liquid crystal dispersed polymer layer is statically reduced. Orientation was performed by the electric field, and an imprint (cutout image) of the symbols “O”, “X”, and “△” could be formed. The images of the symbols “○”, “×”, and “△” are formed by the image forming portion of the stamp material contacting the display body of the liquid crystal board in a short contact time, and have excellent flexibility. As a result, clear images of “、”, “X”, and “△” were obtained.

Comparative Example 1 A chloroprene rubber (trade name: Skyprene B-30, manufactured by Tosoh Corporation) was heated at 140 ° C. to obtain a stamp material similar to that of Example 2. The stamp material has a volume resistivity of 3
Shows a value of × 10 ¹¹ Ω · cm, but lacks flexibility.
The outline of the image formed on the liquid crystal board was not clear.

[0024]

According to the present invention, a stamp which satisfies repeated use can be formed in a short time on a liquid crystal board, and a display image of the liquid crystal board is not damaged. Material can be provided.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a stamp material for a liquid crystal board according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a state in which the stamp material for a liquid crystal board of FIG. 1 is used for a liquid crystal board.

FIG. 3 is a perspective view showing a state in which a stamp material for a liquid crystal board according to another embodiment of the present invention is used for a liquid crystal board.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Stamp material for liquid crystal boards 11 Holding part 12 Image forming part 2 Liquid crystal board 21 Display body 22 Frame body 23 Contact part 3 Image

Claims (4)

[Claims] 1. An externally applied or removed electrostatic charge to a liquid crystal board display surface provided with a conductive layer and a liquid crystal dispersed polymer layer in which liquid crystal is finely dispersed in a polymer matrix on the conductive layer. A stamp material capable of forming or erasing an image by changing its state, said stamp material comprising a plasticizer and having a volume resistivity of 1 × 10 ⁷ to 1 × 10 ^7.
A stamp material for a liquid crystal board, which is a resin molded product of × 10 ¹² Ω · cm. 2. The stamp material for a liquid crystal board according to claim 1, wherein the resin molded product contains a plasticizer in a resin selected from a vinyl chloride resin and / or a vinyl chloride-vinyl acetate copolymer resin. 3. The stamp material for a liquid crystal board according to claim 1, wherein the plasticizer is contained in an amount of 15 to 50% by weight. 4. The plasticizer is 2,2,4-trimethyl-
The stamp for a liquid crystal board according to any one of claims 1 to 3, wherein the plasticizer is a plasticizer using one or more selected from 1,3-pentanediol diisobutyrate, a phthalate ester type, and a dibasic ester type. Wood.