JP3292703B2 - Method for manufacturing panel for magnetophoretic display - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a magnetophoretic display panel for displaying images by using magnetophoresis.

[0002]

2. Description of the Related Art Generally, as a drawing board for infants,
A paper honeycomb core having a large number of hexagonal cells is sealed between a transparent or translucent drawing surface plate (substrate) and a surface material opposed thereto, and a plastic dispersion liquid containing magnetic particles is filled in each of the cells. Enclosed magnetic picture plates are known.

[0003] In this method, a magnetic field is applied to a dispersion liquid by bringing the tip of a magnetic pen into contact with a drawing surface to cause magnetic particles to float on the drawing surface, and a difference in contrast between the dispersion medium and the magnetic particles is applied to the drawing surface. By displaying pictures and characters and moving the eraser bar under the substrate, the floating magnetic particles are submerged again to erase the pictures and characters.

Conventionally, the paper honeycomb core of such a magnetophoretic display panel is made of vinyl chloride. However, the present inventors have developed a paper honeycomb core made of paper instead. Paper honeycomb cores have the advantages of less showing the honeycomb shape on the drawing surface, low cost, light weight, etc., and they can be disposed of safely, so they also clear the recent problem of environmental hormones. be able to.

[0005] By the way, in order to manufacture a paper honeycomb core, a large number of strips of paper are stretched from a stacked state, and each cell is fixed to a state in which each cell is almost exactly hexagonal, that is, a state in which a honeycomb is formed. Must. The conventional honeycomb core made of vinyl chloride paper has almost no problem since the expanded state is maintained even after the force is released after the expansion.

[0006]

However, in the case of a paper honeycomb core made of paper, when the force is released after the paper core is expanded, the paper honeycomb core contracts in a direction to return to the original shape due to the inherent elasticity of the paper. Therefore, even if the central cell is a regular hexagon, the shapes of the cells on both sides are easily collapsed. If the cell shape is non-uniform, the drawing line becomes non-uniform or bleeding occurs, so that the drawing quality is impaired and the amount of paper honeycomb cores per unit is also increased. . Therefore, it is necessary to use a special jig or device to maintain the shape of the paper honeycomb core after the expansion, but in this case, it is not possible to prepare a large number of paper honeycomb cores in advance. However, there is a problem that it cannot be mass-produced.

[0007] The present invention solves the above-mentioned problems, and can maintain the cell shape of the expanded paper honeycomb core without using a special device so that the cell shape becomes uniform. An object of the present invention is to provide a method for manufacturing a magnetophoretic display panel capable of mass-producing a honeycomb core.

[0008]

In order to solve the above problems, a method for manufacturing a magnetophoretic display panel according to the present invention comprises:
It is characterized by comprising the following steps. (A) A core material obtained by polymerizing and bonding a large number of strip-shaped paper pieces made of pulp material such as glassine paper and parchment paper via an adhesive applied at regular intervals alternately to the front and back surfaces facing each other. The process of spreading. (B) a step of humidifying the core material; (C) a step of drying the core material. (D) A step of forming a paper honeycomb core by cutting into a predetermined size after drying. (E) A step of bonding the panel to one of the front and back surfaces of the paper honeycomb core after cutting. (F) A step of filling a plastic dispersion liquid containing magnetic particles inside each cell of the paper honeycomb core.

The humidification in the step (b) may be humidification by spraying steam or water.

In addition, instead of the humidifying step in the above step (b), a step of spraying a binder liquid obtained by mixing a binder and a solvent may be performed.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 is an explanatory view schematically showing the method of the present invention. In carrying out the method of the present invention, a paper honeycomb core is first manufactured as shown in FIGS. For this purpose, first, the core material 1 shown in FIG. 2 is stretched as shown in FIG. As shown in FIGS. 3 (a) and 3 (b), the core material 1 is produced by polymerizing and bonding a large number of strip-shaped paper pieces 2 via an adhesive 3 which is alternately applied to the front and back surfaces facing each other at regular intervals. I do. The material of the paper piece 2 is oil-resistant pulp raw paper. Usually, it is preferable to use glassine paper (for example, "Glasin (trade name)" and "Chrislap (trademark)" manufactured by Oji Paper). Glassine paper is made from carefully selected pulp,
The feature is high transparency. In addition, it is 30 times the thickness of the conventional honeycomb core made of vinyl chloride paper (about 60μ).
The thickness can be about μ to 40 μ. Other features include high resistance to oils and fats, and exceptionally high strength and tensile strength.

The weight of glassine paper is 25 to 65 g / m ^2.
Those in the range are suitable. The reason is that if it is 25 g / m ² or less, the thickness becomes 25 μ or less, the overall strength is insufficient,
If it is 65 g / m ² or more, the strength is sufficient, but the thickness is increased, and there is a disadvantage that it appears on the drawing surface. The optimum is 35.5 ± 2.0 to 41.0 ± 2.0 g / m ² .

Note that parchment paper having similar characteristics may be used. In this case, 30.0 to 60.0 g / m ² is suitable, but 35.0 to 45.0 g / m ² is optimal.

In the case of glassine paper, for example, the adhesive 3 is mainly composed of a mixture of 49 to 51% of ethyl acetate and 49 to 51% of a urethane resin, and is a mixture of 75% of a polyisocyanate prepolymer and ethyl acetate. Things as curing agents,
What is necessary is to use a two-liquid mixture type in which 10 parts of a curing agent is blended with 100 parts of a main agent. The adhesive may be selected from vinyl acetate-based, acrylic-based, and UV-curable adhesives.

Further, as shown in FIG. 4 (a), an adhesive 5 is applied to the front and back surfaces of a large number of paper sheets 4 alternately at regular intervals in a strip shape. ), The two paper sheets 4a of the same size are sandwiched between two paper sheets 4a and polymerized, and the paper sheets that have been polymerized by heating, pressing, etc. are bonded to each other, and then the direction perpendicular to the adhesive application direction as shown in FIG. Can also be obtained by cutting like a line P at a predetermined width.

Next, the core material 1 is processed in the following steps to form a paper honeycomb core in which each cell has a substantially uniform shape. (a) Stretching Step The core material 1 is stretched by pulling the core material 1 from both ends in the forward and backward direction of the strip 2. With proper expansion, each cell becomes approximately a regular hexagon. In order to extend the core material 1 in this manner, a manual method in which two workers pull each end may be used, but in this case, after the extension, the pin 20 is pulled as shown in FIG.
, And fixed to the support member 21, and then proceed to the subsequent steps.

The extension of the contact arm member 1 is shown in FIG.
8 may be performed by the stretching device shown in FIG. In these figures, reference numeral 6 denotes a frame. Rail means 7 are provided on both upper sides of the frame body 6, and two core material holders 8 are movably bridged along the rail means 7 on the rail means 7 on both sides. The mechanism for moving the core material holder 8 may be any mechanism that moves the core material holder 8 along the rail means, and a configuration in which wheels provided below the core material holder 8 roll on a normal rail. It is not limited to. For example, a configuration in which a number of rollers are arranged in parallel on both sides of the upper portion of the frame body, and the bottom surface of the core material holding body is slid along the rollers on both sides may be adopted.

A hollow portion 10 is formed inside the core material holding member 8, and a suction hole 11 is formed on a surface facing the other core material holding member 8. A horizontal support piece 13 is formed at the lower part on the outside. The bottom is connected to a common air pump 15 via an air tube 14. A pressing plate 16 is disposed above the suction hole 11 so as to be able to move up and down, and is urged by a spring 17 so as to be always at an upper position. A pressing means 18 for pressing the pressing plate 16 downward against the force of the spring 17 of the spring 17 is attached to the upper part of the core material holding member 8. The height from the support piece 13 to the upper end of the suction hole 11 is set to be smaller than the width of the strip 2 of the paper honeycomb core. The thickness of the pressing plate 16 is also 2
The thickness is set to about three sheets.

Further, the core material holder 8 is provided with the rail means 7.
At the same time, approach the same amount of movement while keeping the top parallel,
It is connected to an appropriate operating mechanism so as to be separated.

In the above configuration, when the core material 1 is stretched, first, the lower end of the band-shaped paper piece 2 at each end of the core material 1 is placed on the support piece 13 of each core material holding member 8, and the end of the band-shaped paper piece is placed. 2 is applied to the suction surface 12. Further, the pressing plate 16 is lowered to be brought into contact with the upper surface of the strip 2 and the pressing means 18 is pressed.
Press and press. Then, when the air pump 15 is operated, the air in the hollow portion 10 is exhausted to the outside through the air tube 14, so that the pressure in the hollow portion 10 is reduced,
The strip 2 is strongly sucked by the suction surface 12. After the strip-shaped paper pieces 2 at both ends are suction-pressed to the core material holders 8 on both sides, the core material holder 8 is moved in the opposite direction along the rail means 7 by the operating mechanism. Thereby, the strip 2 of the core material 1
Is stretched by being pulled forward. In addition, depending on the selection of the thickness of the material, etc., air may flow from the gap between the paper fibers into the hollow portion 1.
0, it is difficult to reduce the internal pressure of the hollow portion 10, but the core material 1 can be simultaneously pressed by the pressing plate 16, so that the end portion is sufficiently held and fixed to the core material holding body 8, and the core material 1 is surely fixed. And a good paper honeycomb core can be manufactured. The above-mentioned humidification and drying may be performed in a state where the above-mentioned stretched state is maintained.

Incidentally, one core material holding member 8 may be fixed to one end of the rail means 7, and only the other core material holding member 8 may move along the rail means 7. Further, the core material holding member 8 is not limited to the one that moves horizontally. You may comprise so that it may move vertically. (b) Humidifying Step (Binder Liquid Spraying Step) Thereafter, the expanded core material 1 is humidified as shown in FIG. 1 (b). The humidification may be performed by heating the water or humidifying by the steam 22 obtained by subjecting the water to ultrasonic treatment.
The water may be atomized and sprayed by a spray means.

Humidification by steam is suitable when the core material is thin and can be humidified in a small amount, and the degree of the humidification can be easily adjusted.
According to the humidification, adverse effects such as generation of wrinkles are small. The humidification by spraying is suitable when the core material is thick and more humidification is required.

[0023] Instead of the humidifying step, a binder liquid obtained by mixing a binder and a solvent may be sprayed.
Basically, any binder may be used, but a fiber-based resin binder, an unsaturated polyester resin-based binder, an acid-cured amino alkyd resin-based binder, and a polyurethane resin-based material having a good affinity for wood, pulp, and paper. A binder, a vinyl butyrase resin binder, a ceramic binder, a nitrocellulose binder, or the like may be used. Also, in consideration of adhesiveness with a core housing body and a face plate, which will be described later, which are adhered to the front and back surfaces of the paper honeycomb core, an acrylic resin-based binder having excellent adhesiveness with polycarbonate, acrylic, or the like, or with polypropylene or the like. A chlorinated polypropylene resin-based binder having excellent properties may be employed.

The solvent may be basically any solvent. Examples of the hydrocarbon solvent include pentane, hexane, heptane, petroleum ether, petroleum benzene, kerosene, cyclohexane, toluene, xylene, and the like.
Ethylbenzene, chloroform, methylene chloride, carbon tetrachloride and the like can be mentioned. As a solvent for alcohols,
Methanol, ethanol, propanol, butanol,
Examples of the amino alcohol and ether solvents include ethyl ether, butyl ether, and isoamyl ether. Further, as a solvent for ketones, acetone,
There are methyl ethyl ketone, meryl isobutyl ketone and the like, and as solvents for esters, ethyl acetate and butyl acetate are known.

The mixing ratio between the solvent and the binder may be such that the binder is about 5 to 10% or less when the binder liquid is 100.

In the above steps, water and liquid molecules infiltrate the fibers of the paper of the core material 1, so that the elasticity is reduced, the fibers are stretched and the stretched state is maintained. (c) Drying process After the humidifying process, the core material 1 is removed from the air 23 as shown in FIG.
Spray to dry. The fibers of the paper are stretched by the humidifying step or the binder liquid spraying step, but by drying the fibers, the fiber state is stabilized, and the contraction of the paper honeycomb core can be temporarily stopped. In particular, in the case of the binder liquid, after the solvent evaporates, as shown in FIG.
5 and acts to hold the shape by entering the recess 26. For this reason, it is more effective than stabilization of the expanded state by humidification. Drying is not limited to air blowing, but may be natural drying.

It is preferable that the size of each cell 27 of the core material 1 is usually such that its maximum width is inscribed in a circle having a maximum width of 2.0 to 8.0 mm. It is technically difficult to form a paper having a maximum width of 2.0 mm or less on paper, and it is unnecessary to use a fine drawing for drawing for infants. It is difficult to control the rise and settling of all the magnetic particles in 27, and there is a possibility that the drawing may be uneven. The optimal value is between 3.0 and 4.0 mm.

The thickness of the core material 1 is preferably about 0.5 mm to 5.0 mm. If the thickness is smaller than 0.5 mm, the magnetic particles can be seen through the outside of the drawing surface in a state of sinking at the bottom of the cell 24, and if the thickness is larger than 5.0 mm, the magnetic force of the magnetic pen or eraser will be unnecessarily large. Because you have to do it. The optimum value is between 0.8 mm and 2.0 mm. (d) Cutting Step Next, the dried core material 1 is removed by appropriate means as shown in FIG.
As shown by a dashed line in FIG. 10, a paper honeycomb core A is cut out from a predetermined size. As shown in FIG. 1 (d), it is efficient to extract a plurality of paper honeycomb cores A at once. For example, the number of laminated core material pieces is 887, and the dimension of the core material before stretching is 500 mm in length.
× Width 40mm × Height 1mm, after expansion 375mm × 1
It is 330 mm × 1 mm, and even if a margin is left, five rectangular paper honeycomb cores having a diameter of one cell of 3 mm and a size of 320 × 230 (mm) in width and length can be cut out. However, as shown in FIG. 10, the number of paper honeycomb cores A to be taken out from one core material 1 may be one.

Next, after the paper honeycomb core was die-cut as described above, one of the front and back surfaces of the paper honeycomb core A was bonded to the dish-shaped panel 28 as shown in FIGS. 1 (e) and 11. Then, the interior of each cell 27 of the paper honeycomb core A is filled with a plastic dispersion liquid containing magnetic particles, and the sheet-like honeycomb core A is opened at the opening of the paper honeycomb core A as shown in FIG. To seal the plastic dispersion liquid 30. In this case, it is desirable to place a weight 31 from above the planar panel as shown in FIG. 1 (h) so that the panels 28 and 29 are not deformed.

When the time elapses after drying, the shape of the paper honeycomb core may change due to temperature, humidity, and the like. Therefore, immediately after the cutting, the dish-shaped panel 28
It is even better to bond to
The process from the expansion of the core material 1 to the die cutting of the paper honeycomb core A in the cutting process and the bonding to the dished panel 28 are continuous, and the production efficiency is improved. From the above,
A panel for magnetophoretic display as shown in FIG. 12 is completed.

The one panel 28 constitutes a drawing surface, and is made of a transparent or translucent olefin synthetic resin, for example, a polyethylene synthetic resin such as PET or a polypropylene synthetic resin such as polypropylene. Is formed into a dish shape so that the concave portion 8 is formed inside by making the peripheral portion higher by vacuum molding or the like. The other panel 29 is planar and is also made of an olefin-based synthetic resin. If the panel is the drawing surface,
This planar panel 29 is made transparent or translucent.

The panels 28 and 29 are not necessarily made of an olefin resin, but may be made of a vinyl chloride resin as in the prior art. Vinyl chloride is excellent in terms of good workability and adhesiveness. Even when vinyl chloride is used, the effect on the environment can be reduced because the paper honeycomb core A is made of paper.

Panels 2 are provided on the front and back surfaces of the paper honeycomb core A.
When bonding 8 and 29, first,
One surface of the honeycomb core A made of paper is bonded thereon. After filling the inside of each cell 27 of the paper honeycomb core A with a milky white plastic dispersion liquid 30 containing magnetic particles, the planar panel 29 is further adhered to the upper portion of the paper honeycomb core A. Thereby, the plastic dispersion liquid 30 is sealed inside.

As the plastic dispersion liquid 30, a magnetic field is applied to the plastic dispersion liquid 30 by bringing the tip of a magnetic pen into contact with the drawing surface or moving the eraser bar to float magnetic particles on the drawing surface or draw. Any device can be used as long as it can sink or move away from the surface to display or delete pictures and characters on the drawing surface. As such a plastic dispersion liquid, a liquid in which magnetic particles, a fine particle thickener, and a colorant are mixed in a dispersion medium is known.

Examples of the dispersion medium include polar dispersion media such as water and glycols, and nonpolar dispersion media such as organic solvents and oils. As the magnetic particles, particles of an oxide magnetic material such as black magnetite, γ-hematite, chromium dioxide, and ferrite, and particles of an alloy-based metallic magnetic material such as iron, cobalt, and nickel may be used. Examples of the fine particle thickener include silicic acid anhydride, hydrous calcium silicate, hydrous aluminum silicate, silica powder, diatomaceous earth, kaolin, clay, benite, etc. Ultra-fine calcium carbonate,
There are ultra-fine activated calcium carbonate, heavy calcium carbonate, hydrated basic magnesium carbonate, barium sulfate and the like, and further, as a coloring agent, there are white pigments and dyes.

As the adhesive for bonding the panel, the dish-shaped panel 3, and the paper honeycomb core A, an acrylic resin-based adhesive that cures at room temperature or an ultraviolet-curable adhesive is preferable.
However, when the dish-shaped panel 3 and the panel are made of an olefin resin, the water absorption is small,
Usually, adhesion is difficult. However, as a result of the experiment,
It was found that the vinyl acetate-based adhesive had good adhesiveness with paper. The reason is that since the solidification of the vinyl acetate resin-based adhesive is performed by the disappearance of the contained solvent, it is necessary that at least one of the adherends is porous.
This is probably because the paper honeycomb core A is made of paper and the fibers of the paper eliminate the contained solvent.

As shown in FIG. 13, the tip of the magnet pen 32 is brought into contact with the drawing surface of the magnetophoretic display panel manufactured as described above, or an eraser slidably arranged on the back side of the panel. By moving 33 to the left and right, a magnetic field is applied to the plastic dispersion liquid 30 to cause the magnetic particles 30a to float on the drawing surface or to settle away from the drawing surface to display or erase pictures and characters on the drawing surface. be able to.

[0038]

According to the first aspect of the present invention, the paper core material is stretched into a paper honeycomb core shape and then humidified, whereby water molecules are added to the paper fibers of the core material. Is infiltrated, the elasticity is reduced, and the fiber is maintained in a stretched and expanded state. Then, by drying, the fibers are stabilized in that state, and the contraction of the paper honeycomb core can be temporarily stopped. This makes it possible to obtain a paper honeycomb core in which each cell is stably held in a hexagonal form without using a special device. Therefore, the paper honeycomb core can be mass-produced, and the mass production of the magnetophoretic display panel having the paper honeycomb core can be realized.

According to the second or third aspect of the present invention, the core material can be humidified by spraying steam or water.

According to the fourth aspect of the invention, since the binder liquid in which the binder and the solvent are mixed is sprayed instead of the humidification step, the binder enters the fiber recess after the solvent evaporates. Act to hold.
Therefore, it is possible to stabilize the form more strongly than in the humidification step.

[Brief description of the drawings]

1 (a) to 1 (h) are explanatory views of the entire process according to the present invention.

FIG. 2 is a perspective view of a core material.

FIGS. 3 (a) and 3 (b) are explanatory views of a manufacturing mode of a core material.

FIGS. 4 (a) and 4 (b) are explanatory views of another embodiment of the core material.

FIG. 5 is a perspective view of a state where the expanded core material is fixed with a pin.

FIG. 6 is a schematic perspective view of the stretching device.

FIG. 7 is an enlarged perspective view of a main part of the stretching device.

FIG. 8 is a cross-sectional view of the stretching device.

FIG. 9 is a partially enlarged view of a paper honeycomb core when a binder liquid is used.

FIG. 10 is a perspective view of a paper honeycomb core.

FIG. 11 is an exploded perspective view showing a state where both surfaces of a paper honeycomb core are bonded to a panel.

FIG. 12 is a completed perspective view of a panel for magnetophoretic display.

FIG. 13 is an enlarged sectional view showing a mode of use of the magnetophoretic display panel.

[Explanation of symbols]

 A Honeycomb core made of paper 1 Core material 2 Strip-shaped paper piece 27 Cell 30 Plastic dispersion liquid

Claims (4)

(57) [Claims] 1. A method for manufacturing a magnetophoretic display panel, comprising the following steps. (A) A core material obtained by polymerizing and bonding a large number of strip-shaped paper pieces made of pulp material such as glassine paper and parchment paper via an adhesive applied at regular intervals alternately to the front and back surfaces facing each other. The process of spreading. (B) a step of humidifying the core material; (C) a step of drying the core material. (D) A step of forming a paper honeycomb core by cutting into a predetermined size after drying. (E) A step of bonding the panel to one of the front and back surfaces of the paper honeycomb core after cutting. (F) A step of filling a plastic dispersion liquid containing magnetic particles inside each cell of the paper honeycomb core. 2. The method for manufacturing a magnetophoretic display panel according to claim 1, wherein the humidification in the step (b) is humidification by steam. 3. The method for manufacturing a magnetophoretic display panel according to claim 1, wherein the humidification in the step (b) is humidification by spraying water. 4. A method for manufacturing a panel for a magnetophoretic display according to claim 1, wherein a step of spraying a binder liquid in which a binder and a solvent are mixed is performed instead of the humidifying step of the step (b). .