JP2007179079A - Air bubble sheet type electronic paper - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently and inexpensively manufacture a display element comprising a cell in which a display medium is enclosed. <P>SOLUTION: A manufacturing apparatus 100 manufactures the display element 204 composed of the air bubble type cell 206 in which the display medium 203 is enclosed by embossing a first film 201 by an embossing roll 111 while continuously and simultaneously producing the first film 201 and a second film 202 by using two extruding dies 141 and 151, transferring the display medium 203 to a display element formation target place of the second film 202, and sticking both the films 201 and 202 together. The sheet 205 on which the display element 204 is formed is wound in a rolled shape. Here, PET films are used as the films 201 and 202. Electron powder fluid (R) is used as the display medium 203. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to information display means (elements, panels, devices) and manufacturing techniques thereof. For example, it relates to the following techniques (1) to (5).
(1) A non-volatile display device, that is, a display device capable of holding an image displayed at the time of power supply even after the power supply is stopped. (2) Between two films at least one of which transmits one or more kinds of display media. And a display device that can display an arbitrary image by changing the appearance of the display medium (the amount to be seen and the type of the visible display medium) for each pixel, and (3) exhibits a first display color and At least one of the first type display medium having a charge of the first polarity and the second type display medium having a second display color and having the charge of the second polarity transmits two pieces of visible light. The positional relationship between the two display media with respect to the observation surface by moving the first type display medium and the second type display medium in opposite directions to each other by the electric field generated between the films and generated in the direction intersecting the two films. To change (4) Display device using particles or powder fluid as a display medium (5) Electronic powder fluid (registered trademark) as a display medium (registration number: 4636931) : Display device using Bridgestone Corporation

  2. Description of the Related Art There is known a display device that uses a particle group or a powdered fluid as a display medium and can display an arbitrary image by changing the amount and type of the display medium that can be seen for each pixel. This type of display device includes cells arranged in an orderly manner along the observation surface and partition walls that partition the cells. A display medium is enclosed in each cell.

  Photolithography, extrusion molding, injection molding, or press molding is used as a method for forming the partition wall for partitioning the cells on the substrate (display medium holder).

JP 2007-65571 A JP 2007-65537 A JP 2007-57788 A JP 2007-57558 A JP 2007-45025 A JP 2007-11227 A JP 2006-337503 A JP 2006-330707 A JP 2006-330233 A JP 2006-317622 A JP 2006-317621 A JP 2006-317613 A JP 2006-317608 A JP 2006-317607 A JP 2006-243169 A JP 2006-221169A JP 2005-321492 A JP 2005-37851 A JP 2006-235220 A JP 2003-279866 A JP 2003-167238 A JP 2002-169190 A JP 2006-235220 A

  As described above, the partition wall for partitioning and forming the cell is conventionally formed on the substrate (display medium holder) by photolithography, extrusion molding, injection molding, or press molding. A substrate (display medium holding body) having the above could only be manufactured by single wafer processing. For this reason, a display element comprising a substrate (display medium holder) and thus a cell enclosing the display medium, a display element sheet having a plurality of cells enclosing the display medium, and a display device including the display element sheet are efficiently produced. It could not be manufactured at a low cost.

  The subject of this invention is providing the manufacturing technique which can manufacture these display elements, a display element sheet | seat, and a display apparatus efficiently and cheaply.

In order to solve the above problems, the present invention employs the following means.
1. Display element manufacturing method 1-1. This is a method of manufacturing a display element by bonding a first film and a second film to each other and enclosing a display medium between the films, and sucking a display element formation target portion of the first film (vacuum suction, vacuum) An embossing step of forming a plurality of convex portions on one surface of the film by simultaneously deforming the first film and the second film, and forming the same number of concave portions as the convex portions on the other surface; After undergoing a display medium supply step of supplying at least one type of display medium to a display element formation target location on at least one of the bonding surfaces of the films, the embossing step, and the display medium supply step And a cell-like cell forming step for forming cell-like cells enclosing a display medium by bonding a second film to the other surface of the first film. Production method.

  According to the manufacturing method 1-1, it is possible to manufacture a display element by a roll-to-roll method. That is, an embossing process, a display medium supplying process, and a cellular cell forming process while continuously running the film using the roll-wound film as the first film and / or the second film. To produce a display element (bubble cell), and the strip-shaped film laminate after forming the display element (bubble cell) can be wound into a roll.

  In addition, according to the manufacturing method 1-1, it is possible to manufacture a display element by a die-to-roll method. “Die-to-roll method” means that a continuous film is continuously produced using a flat die while the film is used as the first film and / or the second film continuously. The embossing process, the display medium supply process, and the bubble cell forming process are carried out while running, and a display element (bubble cell) is manufactured, and the band-shaped film laminate after forming the display element (bubble cell) is rolled. It is a production method (method) that winds up into a shape. Instead of or in addition to the flat die method (T die method), an inflation method or a multilayer (lamination) molding method can also be used. For details on the film molding method, see “Patent Map by Technology Field” on the JPO website (https://www.jpo.go.jp/shiryou/s_sonota/map/kagaku06/4/4-7-1.htm) (As of February 8, 2007).

1-2. The display medium supplying step is a step of supplying at least one type of display medium to the concave portion of the first film, or a portion overlapping the concave portion of the bonding surface of the second film with the first film. A display element manufacturing method, which is a step of supplying at least one type of display medium.
1-3. The display medium supplying step includes a latent image forming step of forming an electrostatic latent image of a predetermined pattern on the surface of the image carrier, a developing step of developing the electrostatic latent image with a display medium, and the developed pattern. And a transfer step for transferring the first film and the second film to at least one of the bonding surfaces of the first film and the second film.
1-4. A display element manufacturing method, wherein the display medium is an electronic powder fluid (registered trademark).

2. Display element manufacturing apparatus 2-1. A device that manufactures a display element by laminating a first film and a second film and enclosing a display medium between the two films, and sucking a display element formation target location on the first film (vacuum suction, vacuum) Forming a plurality of convex portions on one surface of the film by simultaneously deforming the first film and the second film, and embossing means for forming the same number of concave portions as the convex portions on the other surface; Display medium supply means for supplying at least one type of display medium to a display element formation target location on at least one of the bonding surfaces of the films, and a second film on the other surface of the first film A display element manufacturing apparatus comprising bubble cell forming means for forming bubble cells in which a display medium is sealed by bonding together.
2-2. A display element manufacturing apparatus comprising first film supply means for feeding a first film from a film roll (film supply source) formed by winding the first film into a roll shape and supplying the film to embossing means.
2-3. A display element manufacturing apparatus comprising second film supply means for feeding a second film from a film roll (film supply source) obtained by winding the second film into a roll shape and supplying the second film to the cellular cell forming means.

  According to the manufacturing apparatus of 2-2 and / or 2-3, it is possible to manufacture a display element by a roll-to-roll method. That is, an embossing process, a display medium supplying process, and a cellular cell forming process while continuously running the film using the roll-wound film as the first film and / or the second film. To produce a display element (bubble cell), and the strip-shaped film laminate after forming the display element (bubble cell) can be wound into a roll.

2-4. A display element manufacturing apparatus comprising a first film supply means for supplying an embossing means while continuously producing a strip-shaped first film using an extrusion die as a film supply source.
2-5. A display element manufacturing apparatus comprising first film supply means for supplying a cell-like cell forming means while continuously producing a strip-like second film using an extrusion die as a film supply source.

  According to the manufacturing apparatus 2-4 and / or 2-5, it is possible to manufacture a display element by a die-to-roll method. That is, while a belt-like film is continuously generated using a flat die, the film is used as the first film and / or the second film, or the film is continuously run, that is, an embossing process, display A display element (bubble cell) is manufactured by performing the medium supply step and the bubble cell forming step, and the band-shaped film laminate after forming the display element (bubble cell) can be wound into a roll.

2-6. The display medium supply means is a means for supplying at least one kind of display medium to the concave portion of the first film, or a portion overlapping the concave portion of the bonding surface of the second film with the first film. A display element manufacturing apparatus which is means for supplying at least one type of display medium.
2-7. The display medium supply means includes a latent image forming means for forming an electrostatic latent image having a predetermined pattern on the surface of the image carrier, a developing means for developing the electrostatic latent image with a display medium, and the developed pattern. The display element manufacturing apparatus which has the transfer means which transcribe | transfers to the display element formation target location of at least one surface among the mutual bonding surfaces of a 1st film and a 2nd film.
2-8. A display element manufacturing apparatus, wherein the display medium is an electronic powder fluid (registered trademark).

3. Display element 3-1. A display element formation target portion of the thermoplastic resin film is sucked (vacuum suction, vacuum suction) and deformed to form a convex portion on one surface and at the same time a concave portion is formed on the other surface. A film, a planar second film (that does not have a concavo-convex portion like the first film) bonded to the other surface of the first film, and the concave portion is formed by the second film. A display element comprising: a bubble cell formed by being closed; and at least one type of display medium enclosed in the bubble cell.
3-2. A display element in which the display medium is an electronic powder fluid (registered trademark).

4). Display element sheet 4-1. A plurality of convex portions are formed on one surface by sucking (depressurizing suction, vacuum suction) and deforming the display element formation target portion of the thermoplastic resin film, and at the same time, the same number of the convex portions on the other surface. A first film in which a concave portion is formed, a second film having a planar shape (that is, not having an uneven portion like the first film) bonded to the other surface of the first film, and A display element sheet comprising a bubble cell formed by closing the recess with a second film, and at least one type of display medium enclosed in the bubble cell.
The display element sheet of 4-1 can be continuously manufactured by a roll-to-roll method or a die-to-roll method.
4-2. A display element sheet, wherein the display medium is an electronic powder fluid (registered trademark).
4-3. A display element sheet in which a cell-shaped cell is expanded in the arrangement direction so that adjacent cell walls are close to each other, and a flat liner film of synthetic resin is attached to the first film. In this display element sheet, the most desirable state is a state in which the walls of adjacent bubble cells are in contact with each other.

5. Display device 5-1. A display device comprising the display element sheet of the present invention and configured to display information by moving the display medium in each bubble cell by applying an electric field to the display medium in the display element sheet.
5-2. A display device in which the display element sheet is held in a compressed state by being sandwiched between two opposing plates, at least one of which is transparent.
5-3. The compressed state is a state in which the bubble cells are pressed between the two plates and deformed, that is, expanded in the cell arrangement direction, so that the adjacent cell walls are closer to each other than before the deformation. Display device. In this display device, the most desirable state is a state where the walls of adjacent bubble cells are in contact with each other.
5-4. The display device in which the plate arranged on the first film side of the display element sheet among the two plates is a transparent plate.

  According to the present invention, a display element including a cell enclosing a display medium, a display element sheet having a plurality of cells enclosing a display medium, and a display device including the display element sheet are efficiently and inexpensively manufactured. Can do.

The best mode for carrying out the present invention will be described.
[Manufacturing equipment, manufacturing method]
FIG. 1 is an apparatus configuration diagram conceptually showing an example of a manufacturing apparatus according to the present invention. The manufacturing apparatus 100 is an apparatus for manufacturing a display element 204 by laminating a first film 201 and a second film 202 to each other and enclosing a display medium 203 between the films 201 and 202 by the manufacturing method according to the present invention. It is.

  The manufacturing apparatus 100 includes embossing means 110, display medium supply means 120, bubble cell forming means 130, first film supply means 140, and second film supply means 150.

  The embossing means 110 includes an embossing roll (embossing cylinder) 111. The embossing roll 111 has a large number of suction portions (holes) arranged in an orderly manner in conformity with the formation conditions of the display elements on the outer peripheral surface thereof, and the embossing roll 111 of the first film 201 supplied from the first film supply means 140. A plurality of convex portions are formed on one surface of the film 201 by simultaneously sucking and deforming the display element formation target location while being gradually cooled while forming the same number of concave portions as the convex portions on the other surface. To do.

  The display medium supply means 120 is connected to the first film 201 and the first film by a series of processes (primary charging, exposure, development, transfer, separation, charge removal, cleaning) similar to the processes performed on the photosensitive drum in the dry copying machine. The display medium 203 is supplied to the display element formation target location of the second film 202 among the bonding surfaces of the two films 202. In this example, the display medium supply unit 120 includes a display medium charge supply device 121, a display medium carrying roller 122, a photosensitive drum 123, an electrostatic latent image forming device 124, and a transfer device 125. . The display medium charge supply device 121 supplies the charged display medium 203 to the display medium carrying roller 122. The electrostatic latent image forming device 124 forms an electrostatic latent image of a predetermined pattern (a pattern composed of a large number of dots arranged in order according to the arrangement of display elements to be formed) on the surface of the photosensitive drum 123. The display medium carrying roller 122 rotates while carrying the display medium 203 on the surface thereof, and supplies the display medium 203 to the surface of the photosensitive drum 123 that rotates in the reverse direction at the same peripheral speed in the vicinity thereof. Thus, the electrostatic latent image on the photosensitive drum 123 is developed (visualized) on the display medium 203. The photosensitive drum 123 rotates while carrying a predetermined pattern formed of the display medium 203 on the surface thereof. The transfer device 125 is provided in the vicinity of the lower side of the photosensitive drum 123 with the passage region of the second film 202 supplied from the second film supply unit 150, and the display medium 203 on the photosensitive drum 123. The predetermined pattern consisting of is transferred (supplied) to the second film 202.

  The cellular cell forming unit 130 has a pressure-bonding roll 131 that is in pressure contact with the embossing roll 111 and rotates in the opposite direction at the same peripheral speed. Then, when the embossed first film 201 and the display medium supplied second film 202 pass between the embossing roll 111 and the pressure-bonding roll 131 (pressure-bonding portion) in a state where they overlap each other. Both the films 201 and 202 are pressure-bonded to the embossing roll 111 with the pressure-bonding roll 131 and bonded to each other by heat-sealing with each other on the surface of the embossing roll 111, thereby forming the bubble cell 206 in which the display medium 203 is enclosed. A number of holes are formed on the outer peripheral surface of the pressure-bonding roll 131 in accordance with the arrangement and dimensions of the suction portions formed on the outer peripheral surface of the embossing roll 111, and only the peripheral portion of the display element formation target location is heated and heated. The two films 201 and 202 can be bonded together by pressing.

  The first film supply unit 140 supplies the band-shaped first film 201 to the embossing unit 110 while continuously generating the band-shaped first film 201 using the extrusion die 141.

  The second film supply means 150 supplies the cell-like cell forming means 130 while continuously generating the band-shaped second film 202 using the extrusion die 151. In this example, the second film 202 passes through the display medium supply unit 120 via the guide roller 152 and is then supplied to the bubble cell forming unit 130.

  The manufacturing apparatus 100 configured as described above uses the two extrusion dies 141 and 151 to simultaneously generate the first film 201 and the second film 202 at the same time while running both the films 201 and 202. The display element 204 can be manufactured by performing an embossing process, a display medium supply process, and a bubble cell forming process. And the strip | belt-shaped film laminated body after the display element formation, ie, the display element sheet | seat 205, can be wound up in roll shape. That is, the manufacturing apparatus 100 can efficiently and inexpensively manufacture the display element sheet 205 by a die-to-roll method.

  In the manufacturing apparatus 100, instead of the extrusion die 141 of the first film supply means 140, a film roll formed by winding the first film 201 into a roll shape is used, and the first film 201 is fed out from the film roll. It is also possible to configure the apparatus to supply to the embossing means 110. Moreover, it replaces with the extrusion shaping | molding die 151 of the 2nd film supply means 150, uses the film roll formed by winding the 2nd film 202 in roll shape, pays out the 2nd film 202 from the said film roll, and is a cellular cell. It is also possible to configure the apparatus to supply the forming means 130. According to these device configurations, the display element sheet 205 can be efficiently and inexpensively manufactured by a hybrid method of the die-to-roll method and the roll-to-roll method.

Moreover, it replaces with the extrusion die 141,151 of both film supply means 140,150, uses a film roll, and unwinds the film 201,202 from each film roll, and supplies it to the embossing means 110 and the bubble cell formation means 130 The device can also be configured to do so. According to this device configuration, the display element sheet 205 can be efficiently and inexpensively manufactured by the roll-to-roll method.

  FIG. 2 is an apparatus configuration diagram conceptually showing another example of the manufacturing apparatus according to the present invention. The manufacturing apparatus 300 attaches the first film 201 and the second film 202 to each other by the manufacturing method according to the present invention, exhibits a first display color between the films 201 and 202, and has a first polarity charge. The display element 207 is manufactured by enclosing the first-type display medium 203B having the second display color and the second-type display medium 203W having the second display color and having the second polarity charge. The first type display medium 203B is a display medium that exhibits a first display color (for example, black) and has a charge of a first polarity (for example, negative). The second type display medium 203W is a display medium that exhibits a second display color (for example, white) and has a charge of the second polarity (for example, positive).

  The manufacturing apparatus 300 includes an embossing means 310, a first display medium supply means 320B, a second display medium supply means 320W, a bubble cell forming means 330, a first film supply means 340, a second Film supply means 350.

  The embossing means 310 includes an embossing roll (embossing cylinder) 311. The embossing roll 311 has a large number of suction portions (holes) arranged in order on the outer peripheral surface in conformity with the formation conditions of the display elements, and the first film 201 supplied from the first film supply means 340. A plurality of convex portions are formed on one surface of the film 201 by simultaneously sucking and deforming the display element formation target location with a suction portion while gradually cooling the display element formation target location, and the same number of concave portions as the convex portions are formed on the other surface. Form.

  The first display medium supply means 320B is the first of the bonding surfaces of the first film 201 and the second film 202 by a series of processes similar to those performed on the photosensitive drum in the dry copying machine. The first type display medium 203B is supplied to the display element formation target location of the second film 202. In this example, the first display medium supply unit 320B includes a display medium charge supply device 321B, a display medium carrying roller 322B, a photosensitive drum 323B, an electrostatic latent image forming device 324B, and a transfer device 325B. is doing. The display medium charge supply device 321B supplies the charged first type display medium 203B to the display medium carrying roller 322B. The electrostatic latent image forming apparatus 324B forms an electrostatic latent image having a predetermined pattern (a pattern composed of a large number of dots arranged in order according to the arrangement of display elements to be formed) on the surface of the photosensitive drum 323B. The display medium carrying roller 322B rotates while carrying the first type display medium 203B on the surface thereof, and the first type display is provided on the surface of the photosensitive drum 323B which is rotated in the reverse direction at the same peripheral speed in the vicinity thereof. By supplying the medium 203B, the electrostatic latent image on the photosensitive drum 323B is developed (visualized) with the first type display medium 203B. The photosensitive drum 323B rotates while carrying a predetermined pattern formed of the first type display medium 203B on the surface thereof. The transfer device 325B is provided in the vicinity of the lower portion of the photosensitive drum 323B with a passage area of the second film 202 supplied from the second film supply means 350, and is the first type on the photosensitive drum 323B. By transferring a predetermined pattern composed of the display medium 203B to the second film 202, the first type display medium 203B is supplied to the display element formation target location of the second film 202.

  The second display medium supply means 320W uses a series of processes similar to the processes performed on the photosensitive drum in the dry copying machine, and the second display medium supply means 320W uses the first display medium among the bonding surfaces of the first film 201 and the second film 202. The second type display medium 203 </ b> W is supplied to the display element formation target location of one film 201. In this example, the second display medium supply unit 320W includes a display medium charge supply device 321W, a display medium carrying roller 322W, a photosensitive drum 323W, an electrostatic latent image forming device 324W, and a transfer device 325W. is doing. The display medium charge supply device 321W supplies the charged second type display medium 203W to the display medium carrying roller 322W. The electrostatic latent image forming device 324W forms an electrostatic latent image having a predetermined pattern (a pattern composed of a large number of dots arranged in order according to the arrangement of display elements to be formed) on the surface of the photosensitive drum 323W. The display medium carrying roller 322W rotates while carrying the second type display medium 203W on the surface thereof, and the second type display is provided on the surface of the photosensitive drum 323W that rotates in the reverse direction at the same peripheral speed in the vicinity thereof. By supplying the medium 203W, the electrostatic latent image on the photosensitive drum 323W is developed (visualized) with the second type display medium 203W. The photosensitive drum 323W rotates while carrying a predetermined pattern formed of the second type display medium 203W on the surface thereof. The transfer device 325 </ b> W includes a transfer voltage application device 326 and an embossing roll 311. The transfer voltage applying device 326 applies a voltage necessary for transferring the second type display medium 203 </ b> W carried on the photosensitive drum 323 </ b> W to the first film 201 to the embossing roll 311. That is, the transfer device 325W transfers the second type display medium 203W to the first film 201W by transferring a predetermined pattern made of the second type display medium 203W on the photosensitive drum 323W to the first film 201 on the embossing roll 311. The film 201 is supplied to a recess which is a display element formation target location.

  The cellular cell forming means 330 has a pressure-bonding roll 331 that rotates in the opposite direction at the same peripheral speed while being pressed against the embossing roll 311. The first film 201 that has been embossed and supplied with the second type display medium and the second film 202 that has already been supplied with the first type display medium are placed between the embossing roll 311 and the press roll 331 (crimping part). When passing in a state where they are overlapped vertically, the two films 201 and 202 are pressure-bonded to the embossing roll 311 by the pressure-bonding roll 331, and are heat-sealed to each other on the surface of the embossing roll 311 so that two kinds of displays are displayed. Bubble cells 209 in which the media 203B and 203W are enclosed are formed. A large number of holes are formed on the outer peripheral surface of the pressure-bonding roll 331 in accordance with the arrangement and dimensions of the suction portions formed on the outer peripheral surface of the embossing roll 311, and only the peripheral portion of the display element formation target location is heated and heated. The two films 201 and 202 can be bonded together by pressing.

  The first film supply unit 340 supplies the band-shaped first film 201 to the embossing unit 110 while continuously generating the band-shaped first film 201 using the extrusion die 341. In this example, the first film 201 extruded from the extrusion molding die 341 is supplied to the embossing roll 311 via the guide roller 342.

  The second film supply means 350 supplies the cell-like cell forming means 330 while continuously producing the band-like second film 202 using the extrusion die 351. In this example, the second film 202 passes through the first display medium supply unit 320 </ b> B via the guide roller 352 and is then supplied to the bubble cell forming unit 330.

  The manufacturing apparatus 300 configured as described above uses the two extrusion dies 341 and 351 to simultaneously generate the first film 201 and the second film 202 at the same time while running both the films 201 and 202. The display element 207 can be manufactured by performing an embossing process, a display medium supplying process, and a bubble cell forming process. And the strip | belt-shaped film laminated body after the display element formation, ie, the display element sheet | seat 208, can be wound up in roll shape. That is, the manufacturing apparatus 100 can efficiently and inexpensively manufacture the display element sheet 208 by a die-to-roll method.

  In the manufacturing apparatus 300, instead of the extrusion die 341 of the first film supply means 340, a film roll formed by winding the first film 201 into a roll shape is used, and the first film 201 is fed out from the film roll. It is also possible to configure the apparatus to supply to the embossing means 310. Moreover, it replaces with the extrusion shaping | molding die 351 of the 2nd film supply means 350, uses the film roll formed by winding the 2nd film 202 in roll shape, pays out the 2nd film 202 from the said film roll, and is a cellular cell. It is also possible to configure the apparatus to supply the forming means 330. According to these device configurations, the display element sheet 208 can be efficiently and inexpensively manufactured by a hybrid method of the die-to-roll method and the roll-to-roll method.

  Further, instead of the extrusion dies 341 and 351 of the both film supply means 340 and 350, film rolls are used, and the films 201 and 202 are fed out from the respective film rolls and supplied to the embossing means 310 and the bubble cell forming means 330. The device can also be configured to do so. According to this device configuration, the display element sheet 208 can be efficiently and inexpensively manufactured by the roll-to-roll method.

  In the above embodiment, the manufacturing apparatus 300 is configured to supply the display medium 203W to the display element formation target portion of the first film 201 after embossing, but the display medium 203W is supplied to the display element formation target portion. The manufacturing apparatus 300 may be configured to emboss the later first film 201.

[Display element sheet]
FIG. 3 is a cross-sectional view illustrating the structure of the display element sheet 205 manufactured by the manufacturing apparatus 100 of FIG. The display element sheet 205 is formed by sucking (depressurizing suction, vacuum suction) and deforming a display element formation target portion of the thermoplastic resin film, thereby forming a plurality of convex portions on one side and simultaneously on the other side. A first film 201 having the same number of concave portions as the convex portions, and a planar shape bonded to the other surface of the first film 201 (that is, having an uneven portion like the first film). The second film 202, the bubble cell 206 formed by closing the concave portion with the second film 202, and the display medium 203 enclosed in the bubble cell 206. .

  FIG. 4 is a cross-sectional view illustrating the structure of the display element sheet 208 manufactured by the manufacturing apparatus 300 of FIG. The display element sheet 208 is formed by sucking (depressurizing suction, vacuum suction) and deforming the display element formation target portion of the thermoplastic resin film, thereby forming a plurality of convex portions on one surface and simultaneously on the other surface. A first film 201 having the same number of concave portions as the convex portions, and a planar shape bonded to the other surface of the first film 201 (that is, having an uneven portion like the first film). The second film 202, the bubble cell 209 formed by closing the concave portion with the second film 202, and two types of display media 203 </ b> B and 203 </ b> W enclosed in the bubble cell 209. And.

  FIGS. 5A to 5D are partial plan views illustrating the arrangement and cell shapes of the bubble cells 206 and 209 in the display element sheet manufactured by the manufacturing apparatus 100 of FIG. 1 or the manufacturing apparatus 300 of FIG. .

[Display device]
FIG. 6 is a partial cross-sectional view showing an embodiment of the display device of the present invention. The display device 410 includes the display element sheet 205 manufactured by the manufacturing apparatus 100 of FIG. 1, and the electric field E is applied to the display medium 203 in the display element sheet 205 to cause the display medium 203 to be in the bubble cells 206. It is configured to display the information by moving it within. The display element sheet 205 is sandwiched and compressed between two plates 411.412 facing each other, at least one of which is transparent. Each bubble cell 206 of the display element sheet 205 is pressed between the two plates 411.412 and deformed, that is, expanded in the arrangement direction of the cells 206, so that the walls of the adjacent bubble cells 206 are in contact with each other. It has become. As described above, the display element sheet 205 is pressed and deformed between the two plates 411.412, and the walls of the adjacent bubble cells 206 are in contact with each other.

  Of the two plates 411.412, the plate 411 disposed on at least the first film side is a transparent plate. A large number of pixel electrodes 413F and 413R that are opposed to each other with the display element sheet 205 in between are arranged in an orderly manner on the inner surface or outer surface of both plates 411.412. In this example, pixel electrodes 413F and 413R are provided on the inner surfaces of both plates 411.412. Of the pixel electrodes 413F and 413R, at least the pixel electrode 413F on the first film 201 side is a transparent electrode.

  In the display device 410 configured as described above, the polarity of one pixel electrode 413F and the other pixel electrode 413R is switched for each electrode pair 413P composed of two pixel electrodes 413F and 413R facing each other. The direction of the electric field E acting on the medium 203 can be switched for each electrode pair 413P to display an image. Therefore, according to the display device 410, high resolution display is possible by making the pixel electrodes 413F and 413R fine and high in density. Since the display element sheet 205 is pressed and deformed between the two plates 411.412 and the walls of the adjacent bubble cells 206 are in contact with each other, the arrangement, dimensions, and The shape has little effect on the resolution. Further, since the display element sheet 205 is sandwiched between the two plates 411.412 and compressed, the internal pressure of each cellular cell 206 is higher than before compression. Less susceptible to changes in environmental temperature and pressure.

  FIG. 7 is a partial sectional view showing another embodiment of the display device of the present invention. The display device 420 includes a display element sheet 208 manufactured by the manufacturing apparatus 300 of FIG. 2, and an electric field E is applied to the two types of display media 203B and 203W in the display element sheet 208 to display the display medium 203B, Information is displayed by moving 203 W in each bubble cell 209. The display element sheet 208 is compressed by being sandwiched between two opposing plates 421.422, at least one of which is transparent. Each bubble cell 209 of the display element sheet 208 is pressed and deformed between the two plates 421.422 so that the walls of the adjacent bubble cells 209 are in contact with each other.

  Of the two plates 421.422, the plate 421 disposed at least on the first film side is a transparent plate. A large number of pixel electrodes 423F and 423R that are opposed to each other with the display element sheet 208 in between are arranged in an orderly manner on the inner or outer surfaces of both plates 421.422. In this example, pixel electrodes 423F and 423R are provided on the inner surfaces of both plates 421.422. Of the pixel electrodes 423F and 423R, at least the pixel electrode 423F on the first film 201 side is a transparent electrode.

  The display device 420 configured as described above displays a display by switching the polarity of one pixel electrode 423F and the other pixel electrode 423R for each electrode pair 423P composed of two pixel electrodes 423F and 423R facing each other. An image can be displayed by switching the direction of the electric field E acting on the media 203B and 203W for each electrode pair 423P. Therefore, according to the display device 420, the pixel electrodes 423F and 423R can be finely and highly densified to display with high resolution. Since the display element sheet 208 is pressed and deformed between the two plates 421.422 and the walls of the adjacent bubble cells 209 are in contact with each other, the arrangement, dimensions, and The shape has little effect on the resolution. Further, since the display element sheet 208 is sandwiched between the two plates 421.422 and compressed, the internal pressure of each cellular cell 209 is higher than before compression. Less susceptible to changes in temperature and pressure in the environment.

  FIG. 8 is a partial sectional view showing still another embodiment of the display device of the present invention. The display device 430 includes a display element sheet 205 manufactured by the manufacturing apparatus 100 of FIG. The display element sheet 205 is housed in a bag body 431 made of a thin transparent film made of resin, with at least one of the sheets being sandwiched between two transparent plates 411.412 facing each other. The bag body 431 is sealed with its inside being evacuated and decompressed. When the internal space of the bag body 431 is evacuated and depressurized, each bubble cell 206 of the display element sheet 205 is pressed between the two plates 411.412 (pressed by atmospheric pressure) and the inside of the cell 206. Due to the expansion of the gas, the cells 206 swell in the arrangement direction of the cells 206, and the walls of the bubble cells 206 adjacent to each other are in contact with each other. In the display device 430, the display element sheet 208 manufactured by the manufacturing apparatus 300 in FIG. 2 can be used instead of the display element sheet 205 manufactured by the manufacturing apparatus 100 in FIG.

[Display medium]
Next, as an example of the display method used in the manufacturing method, manufacturing apparatus, display element, display element sheet, and display apparatus of the present invention, an electronic powder fluid (registered trademark) can be cited. The following explanation regarding the electronic powder fluid (registered trademark) is quoted from Japanese Patent Application Laid-Open No. 2006-330707 (Applicant: Bridgestone Co., Ltd.). Alternatively, it can be read as a display device and is consistent with the present invention.

The “powder fluid” in the present invention is a substance in an intermediate state of both fluid and particle characteristics that exhibits fluidity by itself without borrowing the force of gas or liquid. For example, liquid crystal is defined as an intermediate phase between a liquid and a solid, and has fluidity that is a characteristic of liquid and anisotropy (optical properties) that is a characteristic of solid (Heibonsha: Encyclopedia) . On the other hand, the definition of particle is an object with a finite mass even if it is negligible, and is said to be affected by gravity (Maruzen: Physics Encyclopedia). Here, even in the case of particles, there are special states of gas-solid fluidized bed and liquid-solid fluids. When gas is flowed from the bottom plate to the particles, upward force is applied to the particles according to the velocity of the gas. Is a gas-solid fluidized bed that is in a state where it can easily flow when it balances with gravity, and it is also called a liquid-solid fluidized state that is fluidized by a fluid (ordinary) Company: Encyclopedia). As described above, the gas-solid fluidized bed body and the liquid-solid fluid are in a state of using a gas or liquid flow. In the present invention, it has been found that a substance in a state of fluidity can be produced specifically without borrowing the force of such gas and liquid, and this is defined as powder fluid.
That is, the pulverulent fluid in the present invention is in an intermediate state having both the characteristics of particles and liquid, as in the definition of liquid crystal (liquid and solid intermediate phase), and is the characteristic of the above-mentioned particles. It is a substance that is extremely unaffected and exhibits a unique state with high fluidity. Such a substance can be obtained in an aerosol state, that is, in a dispersion system in which a solid or liquid substance is stably suspended as a dispersoid in a gas, and the solid substance is regarded as a dispersoid in the information display panel of the present invention. To do.
The information display panel of the present invention encloses a powder fluid exhibiting high fluidity in an aerosol state in which solid particles are stably suspended as a dispersoid, for example, in a gas between opposing substrates, at least one of which is transparent. Yes, such a pulverulent fluid exhibits a state that is so fluid that it does not form an angle of repose, which is an index indicating the fluidity of the powder. Coulomb force is generated by an electric field formed by applying a low voltage, etc. It can be easily and stably moved.
As described above, for example, the powder fluid used as a display medium in the present invention is a substance in an intermediate state between fluid and particles that exhibits fluidity by itself without borrowing the force of gas or liquid. It is. This powder fluid can be in an aerosol state in particular, and in the information display panel of the present invention, it is used as a display medium that can easily create a state in which a solid substance floats relatively stably as a dispersoid in a gas. .
Next, display medium particles (hereinafter also referred to as particles) constituting the display medium in the information display panel of the present invention will be described. The display medium particles are composed of the display medium particles as they are to form a display medium, or are combined with other particles to form a display medium, or adjusted and configured to become a powder fluid to form a display medium. Or used.
The particles can contain a charge control agent, a colorant, an inorganic additive, and the like, if necessary, in the resin as the main component, as in the conventional case. Examples of resins, charge control agents, colorants, and other additives will be given below.
Examples of the resin include urethane resin, urea resin, acrylic resin, polyester resin, acrylic urethane resin, acrylic urethane silicone resin, acrylic urethane fluororesin, acrylic fluororesin, silicone resin, acrylic silicone resin, epoxy resin, polystyrene resin, styrene Acrylic resin, polyolefin resin, butyral resin, vinylidene chloride resin, melamine resin, phenol resin, fluororesin, polycarbonate resin, polysulfone resin, polyether resin, polyamide resin and the like can be mentioned, and two or more kinds can be mixed. In particular, acrylic urethane resin, acrylic silicone resin, acrylic fluororesin, acrylic urethane silicone resin, acrylic urethane fluororesin, fluororesin, and silicone resin are suitable from the viewpoint of controlling the adhesive force with the substrate.
The charge control agent is not particularly limited. Examples of the negative charge control agent include salicylic acid metal complexes, metal-containing azo dyes, metal-containing oil-soluble dyes (including metal ions and metal atoms), and quaternary ammonium salt systems. Examples thereof include compounds, calixarene compounds, boron-containing compounds (benzyl acid boron complexes), and nitroimidazole derivatives. Examples of the positive charge control agent include nigrosine dyes, triphenylmethane compounds, quaternary ammonium salt compounds, polyamine resins, imidazole derivatives, and the like. In addition, metal oxides such as ultrafine silica, ultrafine titanium oxide, ultrafine alumina, nitrogen-containing cyclic compounds such as pyridine and derivatives and salts thereof, various organic pigments, resins containing fluorine, chlorine, nitrogen, etc. are also charged. It can also be used as a control agent.
As the colorant, various organic or inorganic pigments and dyes as exemplified below can be used.
Examples of the black colorant include carbon black, copper oxide, manganese dioxide, aniline black, activated carbon and the like.
Examples of blue colorants include C.I. I. Pigment blue 15: 3, C.I. I. Pigment Blue 15, Bituminous Blue, Cobalt Blue, Alkaline Blue Lake, Victoria Blue Lake, Phthalocyanine Blue, Metal-free Phthalocyanine Blue, Phthalocyanine Blue Partial Chlorides, Fast Sky Blue, Indanthrene Blue BC, and the like.
Examples of red colorants include bengara, cadmium red, red lead, mercury sulfide, cadmium, permanent red 4R, risor red, pyrazolone red, watching red, calcium salt, lake red D, brilliant carmine 6B, eosin lake, rhodamine lake B, Alizarin Lake, Brilliant Carmine 3B, C.I. I. Pigment Red 2 etc.
Yellow colorants include chrome yellow, zinc yellow, cadmium yellow, yellow iron oxide, mineral first yellow, nickel titanium yellow, navel yellow, naphthol yellow S, Hansa Yellow G, Hansa Yellow 10G, Benzidine Yellow G, Benzidine Yellow GR, Quinoline Yellow Lake, Permanent Yellow NCG, Tartrazine Lake, C.I. I. Pigment Yellow 12 etc.
Examples of green colorants include chrome green, chromium oxide, pigment green B, C.I. I. Pigment Green 7, Malachite Green Lake, Final Yellow Green G, etc.
Examples of the orange colorant include red chrome yellow, molybdenum orange, permanent orange GTR, pyrazolone orange, Vulcan orange, indanthrene brilliant orange RK, benzidine orange G, indanthrene brilliant orange GK, C.I. I. Pigment Orange 31 etc.
Examples of purple colorants include manganese purple, first violet B, and methyl violet lake.
Examples of white colorants include zinc white, titanium oxide, antimony white, and zinc sulfide.
As extender pigments, barite powder, barium carbonate, clay, silica, white carbon,
There are talc and alumina white. Examples of various dyes such as basic, acidic, disperse, and direct dyes include nigrosine, methylene blue, rose bengal, quinoline yellow, and ultramarine blue.
Examples of inorganic additives include titanium oxide, zinc white, zinc sulfide, antimony oxide, calcium carbonate, lead white, talc, silica, calcium silicate, alumina white, cadmium yellow, cadmium red, cadmium orange, titanium yellow, Examples include bitumen, ultramarine blue, cobalt blue, cobalt green, cobalt violet, iron oxide, carbon black, manganese ferrite black, cobalt ferrite black, copper powder, and aluminum powder.
These pigments and inorganic additives can be used alone or in combination. Of these, carbon black is particularly preferable as the black pigment, and titanium oxide is preferable as the white pigment.
The above colorant can be blended to produce display medium particles having a desired color.
Further, the particles of the present invention preferably have an average particle diameter d (0.5) in the range of 0.1 to 20 μm, and are uniform and uniform. If the average particle diameter d (0.5) is larger than this range, the display is not clear. If the average particle diameter d (0.5) is smaller than this range, the cohesive force between the particles becomes too large, which hinders movement as a display medium.
Furthermore, in the present invention, regarding the particle size distribution of the particles for each display medium, the particle size distribution Span represented by the following formula is less than 5, preferably less than 3.
Span = (d (0.9) −d (0.1)) / d (0.5)
(However, d (0.5) is a numerical value expressing the particle diameter in μm that 50% of the particles are larger than this and 50% is smaller than this, and d (0.1) is a particle in which the ratio of the smaller particles is 10%. (Numerical value expressed in μm, and d (0.9) is a numerical value expressed in μm for a particle diameter of 90% or less.)
By keeping Span within a range of 5 or less, the size of each particle is uniform, and uniform movement as a display medium is possible.
Furthermore, regarding the correlation between the particles for each display medium, the ratio of d (0.5) of the particles having the minimum diameter to d (0.5) of the particles having the maximum diameter among the used particles is 50 or less, preferably 10 or less. It is important to do. Even if the particle size distribution Span is reduced, particles with different charging characteristics move in opposite directions, so that the particle size is close to each other and each particle can be easily moved in the opposite direction by the equivalent amount. This is within this range.
When the information display panel manufactured according to the present invention is used as a dry information display panel for driving a display medium in an air space, the gas in the space surrounding the display medium (that is, the gas in the bubble cell) is managed. It is important and contributes to improved display stability. Specifically, it is important that the relative humidity at 25 ° C. is 60% RH or less, and preferably 50% RH or less for the humidity of the gas in the gap.
The gas in the gap is not limited as long as it is in the humidity region described above, but dry air, dry nitrogen, dry argon, dry helium, dry carbon dioxide, dry methane, and the like are preferable. This gas needs to be sealed in an information display panel so that the humidity is maintained, for example, filling a display medium, assembling an information display panel in a predetermined humidity environment, It is important to apply a sealing material and a sealing method that prevent moisture from entering from the outside.

[Sheet]
Next, the production method, production apparatus, display element, display element sheet, and film (first film, second film) used in the display apparatus of the present invention will be described.

As a film material, a known thermoplastic resin can be used. Examples of the thermoplastic resin include polyethylene (low density polyethylene, high density polyethylene, ethylene / α-olefin copolymer), polypropylene, olefin polymer having 2 to 10 carbon atoms such as 4-methylpentene-1, and polyvinyl chloride. Polycondensation products such as halogenated polymers such as polyvinylidene chloride and polyvinyl fluoride, addition polymers such as polystyrene, amide polymers such as nylon 6 and nylon 12, polyester polymers such as polyethylene terephthalate and polybutylene terephthalate, Biodegradable resins such as polylactic acid and polylactone can be used. In particular, an olefin polymer is preferable because it has good airtightness, processability, and mechanical properties and is inexpensive.
It is preferable to use a film such as a thermoplastic resin produced by extrusion molding such as inflation molding or T-die molding. In particular, the manufacturing process can be simplified by adopting a system in which the film is supplied directly from the T-die to the embossing cylinder.
Examples of the olefin polymer include low density polyethylene, high density polyethylene, a copolymer of ethylene and an α-olefin having 3 to 10 carbon atoms, an ethylene-vinyl acetate copolymer, an ethylene-alkyl acrylate copolymer, ethylene. It is preferable to use a phenyl acrylate copolymer, an ethylene-benzyl acrylate copolymer, polypropylene, a copolymer of propylene and an α-olefin having 4 to 10 carbon atoms, and a mixture thereof.

  Moreover, as a film used with the manufacturing method of this invention, a manufacturing apparatus, a display element, a display element sheet | seat, and a display apparatus, it is for electronic paper as described in Unexamined-Japanese-Patent No. 2007-45025 (Applicant: Mitsubishi Chemical Polyester Film Co., Ltd.). It is also possible to use a polyester film. This film has an easy-adhesion layer or a hard coat layer on at least one surface, has a haze value of 1.5% or less, an average value of Ra values on the front and back surfaces is 0.004 to 0.015 μm, and 150 The film has a feature that the absolute value of the heat shrinkage in the machine direction and the transverse direction after treatment at 1 ° C. for 1 hour is 0.7% or less. The polyester here is obtained by polycondensation of an aromatic dicarboxylic acid and an aliphatic glycol, for example. Examples of the aromatic dicarboxylic acid include terephthalic acid and 2,6-naphthalenedicarboxylic acid, and examples of the aliphatic glycol include ethylene glycol, diethylene glycol, and 1,4-cyclohexanedimethanol. A typical and cheapest polyester is polyethylene terephthalate (PET).

[Other Embodiments]
2, the embossing roll 311 forms part of the transfer device 325W of the second display medium supply unit 320W. Like the first display medium supply unit 320B, the embossing roll 311 is photosensitive. The transfer drum may be provided in the vicinity of the lower portion of the photoconductive drum 323W with the photoconductive drum 323W being arranged away from the embossing roll 311 and the passage area of the first film 201 being separated.

  In the example of FIG. 6, each bubble cell 206 is kept inflated in the arrangement direction by sandwiching the display element sheet 205 between the two plates 411.412. The state may be maintained by attaching a flat liner film of synthetic resin to the first film 201 in a state where the method is simultaneously pressed and expanded in the arrangement direction. The same applies to FIG.

  In the above description, a manufacturing method, a manufacturing apparatus, a display element, a display element sheet, and a display device using an electronic powder fluid (registered trademark) as a display medium have been described. However, the display medium used in the present invention is an electronic powder fluid ( (Registered trademark). For example, a dispersion composed of dispersed particles and a colored solution may be used as the display medium. Further, a display medium that is a microcapsule of a dispersion composed of dispersed particles and a colored solution may be used. If this type of display medium is used, an electrophoretic display means can be realized. As a method of supplying the dispersion liquid into the cell, an ink jet method can be exemplified.

Apparatus configuration diagram conceptually showing an example of a manufacturing apparatus according to the present invention Apparatus configuration diagram conceptually showing another example of the manufacturing apparatus according to the present invention. Sectional drawing which illustrates the structure of the display element sheet | seat manufactured with the manufacturing apparatus of FIG. Sectional drawing which illustrates the structure of the display element sheet | seat manufactured with the manufacturing apparatus of FIG. (A)-(d) is a partial top view which illustrates arrangement | positioning and cell shape of a bubble cell in the display element sheet | seat manufactured with the manufacturing apparatus of FIG. 1, or the manufacturing apparatus of FIG. The fragmentary sectional view which shows the example of a form of the display apparatus of this invention The fragmentary sectional view which shows another example of a form of the display apparatus of this invention The fragmentary sectional view which shows another example of a form of the display apparatus of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 100 Manufacturing apparatus 110 Embossing means 111 Embossing roll 120 Display medium supply means 121 Display medium charge supply apparatus 122 Display medium carrying roller (developing means)
123 Photosensitive drum (image carrier)
124 Electrostatic latent image forming apparatus (latent image forming means)
125 Transfer device (transfer means)
DESCRIPTION OF SYMBOLS 130 Cell-like cell formation means 131 Pressure bonding roll 140 1st film supply means 141 Extrusion die (film supply source)
150 Second film supply means 151 Extrusion die (film supply source)
201 First film 202 Second film 203 Display medium

203B Type 1 display medium 203W Type 2 display medium 204 Display element 206 Bubble cell

207 Display element 208 Display element sheet 209 Bubble cell

DESCRIPTION OF SYMBOLS 300 Manufacturing apparatus 310 Embossing means 311 Embossing roll 320B 1st display medium supply means 320W 2nd display medium supply means 321B Display medium charge supply apparatus 321W Display medium charge supply apparatus 322B Display medium support roller (development means)
322W display medium carrying roller (developing means)
323B Photosensitive drum (image carrier)
323W Photosensitive drum (image carrier)
324B Electrostatic latent image forming device (latent image forming means)
324W electrostatic latent image forming device (latent image forming means)
325B transfer device (transfer means)
325W transfer device (transfer means)
326 Transfer voltage application device 330 Cell-like cell forming means 331 Pressure-bonding roll 340 First film supply means 341 Extrusion die (film supply source)
350 Second film supply means 351 Extrusion die (film supply source)
410 display device 411.412 plate 413F, 413R pixel electrode 413P electrode pair 420 display device 421.422 plate 430 display device 431 bag body E electric field

Claims (16)

A method of manufacturing a display element by laminating a first film and a second film together and enclosing a display medium between the two films,
An embossing step of forming a plurality of convex portions on one surface of the film by sucking and deforming the display element formation target portion of the first film and simultaneously forming the same number of concave portions as the convex portions on the other surface When,
A display medium supply step of supplying at least one type of display medium to a display element formation target location on at least one of the bonding surfaces of the first film and the second film;
After passing through the embossing step and the display medium supplying step, a bubble cell forming step of forming a bubble cell in which the display medium is sealed by bonding a second film to the other surface of the first film A display element manufacturing method comprising: The display medium supply step includes
Supplying at least one type of display medium to the concave portion of the first film, or at least one type of display medium at a position overlapping the concave portion of the bonding surface of the second film to the first film The method of manufacturing a display element according to claim 1, wherein The display medium supply step includes
A latent image forming step of forming an electrostatic latent image of a predetermined pattern on the surface of the image carrier;
A developing step of developing the electrostatic latent image with a display medium;
The display element manufacturing method according to claim 1, further comprising a transfer step of transferring the developed pattern to at least one of the bonding surfaces of the first film and the second film.   The display element manufacturing method according to claim 1, wherein the display medium is an electronic powder fluid (registered trademark). An apparatus for manufacturing a display element by laminating a first film and a second film together and enclosing a display medium between the two films,
Embossing means for forming a plurality of convex portions on one surface of the film by sucking and deforming the display element formation target portion of the first film and simultaneously forming the same number of concave portions as the convex portions on the other surface When,
Display medium supply means for supplying at least one type of display medium to a display element formation target location on at least one surface of the bonding surfaces of the first film and the second film;
A display element manufacturing apparatus, comprising: a cellular cell forming unit configured to form a cellular cell in which a display medium is sealed by bonding a second film to the other surface of the first film. The display medium supply means includes
Means for supplying at least one type of display medium to the concave portion of the first film, or at least one type of display medium at a position overlapping the concave portion of the bonding surface of the second film to the first film The display element manufacturing apparatus according to claim 5, wherein the display element manufacturing apparatus is a means for supplying the above. The display medium supply means
Latent image forming means for forming an electrostatic latent image of a predetermined pattern on the surface of the image carrier;
Developing means for developing the electrostatic latent image with a display medium;
7. A display element according to claim 5 or 6, further comprising transfer means for transferring the developed pattern to a display element formation target location on at least one of the bonding surfaces of the first film and the second film. Manufacturing equipment.   The display element manufacturing apparatus according to claim 5, wherein the display medium is an electronic powder fluid (registered trademark). A first film in which a convex portion is formed on one surface thereof by simultaneously sucking and deforming a display element formation target portion of the thermoplastic resin film, and a concave portion is formed on the other surface;
A planar second film bonded to the other surface of the first film;
A cellular cell formed by closing the recess by the second film;
A display element comprising: at least one type of display medium enclosed in the bubble cell.   The display element according to claim 9, wherein the display medium is an electronic powder fluid (registered trademark). A plurality of convex portions are formed on one surface by sucking and deforming the display element formation target portion of the thermoplastic resin film, and at the same time, the same number of concave portions as the convex portions are formed on the other surface. And the film
A second film having a planar shape (that is, not having an uneven portion like the first film) bonded to the other surface of the first film;
A cellular cell formed by closing the recess by the second film;
A display element sheet comprising: at least one type of display medium enclosed in the cellular cell.   The display element sheet according to claim 11, wherein the display medium is an electronic powder fluid (registered trademark).   A display device comprising the display element sheet according to claim 11 or 12 and configured to display information by moving the display medium in each bubble cell by applying an electric field to the display medium in the display element sheet. .   The display device according to claim 13, wherein the display element sheet is held in a compressed state by being sandwiched between two opposing plates, at least one of which is transparent.   15. The display according to claim 14, wherein the compressed state is a state in which the cell walls adjacent to each other are brought closer to each other as a result of the cell being pressed and deformed between the two plates. apparatus.   The display device according to claim 14 or 15, wherein a plate disposed on the first film side of the display element sheet among the two plates is a transparent plate.