JP4696535B2 - Probe contact mechanism for front plate inspection in electrophoretic display - Google Patents

Description

  The present invention relates to a probe contact mechanism used in an inspection of a front plate which is one of components of an electronic paper display as an electrophoretic display device.

  Various methods are being developed as technologies for realizing an electronic paper display having high visibility, rewritable characteristics and low power consumption. A display using an electrophoretic phenomenon uses a phenomenon in which charged particles in a solvent move by an electric field. As one of the techniques, a microcapsule type electrophoresis system has been put into practical use. In this method, positively and negatively charged white particles and black particles are placed in a microcapsule filled with a transparent liquid, and an image is formed by pulling up each particle to the display surface by applying an external voltage. Since the microcapsule size (φ) is as small as several tens μm to several hundreds μm, when the microcapsules are dispersed in a transparent binder, they can be coated like ink. This ink is called electronic ink because an image can be drawn by applying a voltage from the outside. When this electronic ink is coated on a transparent film on which a transparent electrode layer is formed and bonded to a substrate on which an electrode circuit for driving an active matrix is formed, an active matrix display panel can be formed. Here, a component in which electronic ink is coated on a film in which a transparent electrode is formed on a transparent film is referred to as a “front plate”, and a substrate on which an active matrix driving electrode circuit is formed is referred to as a “back plate”. Various defects occur in the front plate. However, if the defect inspection is performed after the two are bonded together, a loss of discarding a normal product of the expensive back plate occurs due to a defect in the front plate. Therefore, it is desired to perform defect inspection at the component stage of each of the front plate and the back plate.

  However, when performing a defect inspection of the front plate, there is a problem that an electrode for applying a voltage to the microcapsule is only on one side. Therefore, the release film of the adhesive layer on the back side of the front plate attached to the back plate is made a conductive film, this conductive release film is used as an electrode instead of the back plate, and the transparent electrode on the surface By applying a voltage between them, the particles in the microcapsule are moved, the front plate is made into three states of white, black, and gray, and all microcapsules can be driven normally. Is called.

  Here, since both the transparent electrode of the front plate and the conductive portion of the release film are in the inner layer, a portion for taking out the voltage is necessary to apply a voltage. The transparent electrode side is called an “electrode extraction portion”, and this portion is also used as an electrode extraction portion when bonded to the back plate. On the other hand, the conductive part side of the release film is called an “inspection tab”.

  By contacting the probe to each of the electrode extraction part and the inspection tab and applying a driving voltage, the particles in the microcapsule can be moved to make the front plate completely white, all black, and all gray. Conventionally, a front plate that does not drive is generated with a frequency of about several percent. It was considered that the front plate that was not driven was caused by a subtle difference in probe contact under the condition that it was driven when driven by another inspection device.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a probe contact mechanism that can stably probe contact and reliably drive the front plate.

In order to solve the above-mentioned problems, the invention according to claim 1 is composed of at least a substrate, a transparent electrode or a driving element by peeling off the release film of the front plate comprising at least a substrate, an electrode, a display material, an adhesive layer and a release film A probe contact mechanism for inspecting the front plate used when inspecting the front plate before peeling the release film of the electrophoretic display device formed by bonding a back plate ,
The release film includes a base film, a conductive layer, and a release layer.
The front plate has a protrusion at a part of its end,
The protruding portion is formed with an inspection tab portion only of a release film, and an electrode extraction portion only of a front plate substrate and a transparent electrode,
The front plate inspection probe contact mechanism is:
A transparent electrode probe capable of contacting the electrode take-out part;
A peeling film side electrode probe capable of contacting the inspection tab part;
A probe holder capable of holding the release film side electrode probe and moving up and down, and covering the vicinity of the electrode take-out portion on the substrate side surface of the front plate;
A probe contact mechanism for inspecting a front plate of an electrophoretic display device, comprising: a stopper capable of adjusting and limiting the height of the probe holder and a stopper adjusting screw .

The invention according to claim 2 is the probe contact mechanism for inspecting a front plate according to claim 1,
In the probe holder, contact between the end portion of the front plate and the peeling film does not occur in the inspection tab portion, and peeling between the front plate and the peeling film in the electrode take-out portion occurs inside the protruding portion. A probe contact mechanism for inspecting a front plate of an electrophoretic display device, the position of which can be adjusted by the stopper and the stopper adjusting screw so as to be disposed at a height that can be accommodated .

  According to the present invention, in front of a display formed by peeling off a release film on a front plate comprising at least a substrate, an electrode, a display material, an adhesive layer and a release film, and bonding a back plate comprising at least a substrate, an electrode or a drive element. In the face plate, by using a conductive film as a peeling film for the front plate, an electric signal for driving the display material can be applied to inspect the presence or absence of display defects before being bonded to the back plate. In the inspection of the front plate, the probe to the peeling film is used by using the probe contact mechanism for inspecting the front plate, wherein the tip shape of the contact probe for applying a voltage to the conductive portion of the peeling film is a sword mountain shape. Contact can be made reliably. In addition, at the end of the push-down height of the block holding the contact probe for applying a voltage to the conductive portion of the release film, the transparent electrode does not contact the conductive portion of the release film, and the effective portion of the front plate By stopping at a height at which peeling does not reach until the transparent electrode part of the front plate and the conductive part of the peeling film are prevented from short-circuiting. Therefore, reliable probe contact is possible. Driving troubles due to imperfect contacts can be prevented.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. First, the configuration of the display will be described.

  For display, a display having a sufficient contrast can be suitably used without a backlight. This is because electroluminescent materials, polymer-dispersed liquid crystals (PDLC), polymer-stable liquid crystals, smectic liquid crystals, ferroelectric liquid crystals, display devices using a microcapsule type electrophoresis system, etc. on a thin flexible substrate. It can be realized by combining. In particular, when a display body using a microcapsule type electrophoresis system is used, an image close to that of conventional paper can be displayed.

  The case where a film-type microcapsule type electrophoresis display is used as the display will be described in detail.

  A cross-sectional view of the display 41 is shown in FIG. An electrode film 41d, an image display layer 41c, an electrode film 41b, and a surface protective layer 41a for protecting the display portion are laminated on a flexible base material 41e such as paper or plastic.

  In this description, the base material 41e corresponds to the substrate described in claims 1 and 2, the electrode film 41d corresponds to the electrode described in claims 1 and 2, and the image display layer 41c is charged. The display material according to Items 1 and 2 corresponds to the display material, and the state in which the electrode film 41d and the image display layer 41c are provided on the base material 41e corresponds to the front plate described in the claims. The surface protective layer 41a can be omitted.

  The electrode film 41b is formed by forming an electrode on a transparent plastic film having excellent dimensional stability such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyimide. The electrode film 41d is also formed by forming a similar base electrode, but transparency is not necessarily required.

  Any electrode method can be selected. However, when the following microcapsule electrophoresis method is used, the electrode film 41b is a common electrode to which the same potential is applied over the entire surface, and the electrode film 41d is active. An electrode such as a matrix electrode or a segment electrode can be employed.

  A configuration when the image display layer 41c is used in a microcapsule electrophoresis method will be described.

  An example of the microcapsule 110 is shown in FIG. The microcapsule 110 has a capsule shell 111 made of methacrylic acid resin, urea resin, gum arabic, or the like. Inside, white particles 113 made of titanium oxide and black particles 114 made of carbon black are highly viscous such as silicone oil. It is dispersed and enclosed in a dispersion medium. White particles of titanium oxide are positively charged, while black particles of carbon black are negatively charged.

  For this reason, as shown in FIG. 6B, when an electric field is applied to the two electrode films 41b and 41d, the electrode film 41b becomes a negative electrode and the electrode film 41d becomes a positive electrode, positively charged white particles Since 113 is drawn to the electrode film 41b side and black particles 114 are drawn to the electrode film 41d side, at least the electrode film 41b is set as a transparent electrode, and when observed from above the electrode film 41b side, the portion looks white.

  Conversely, when the electrode film 41b is a positive electrode and the electrode film 41d is a negative electrode, positively charged white particles 113 are drawn to the electrode film 41d side, and black particles 114 are drawn to the electrode film 41b side. When observed from above the electrode film 41b, the portion looks black.

  The image display layer 41c has a large number of such microcapsules 110. By controlling the electric field of each address electrode of the electrode films 41b and 41d, the letter “A” in FIG. As displayed, a desired character or figure can be displayed with white and black pixels.

In the above example, the microcapsule is a monochrome (black and white) display containing two types of black and white particles, but by adjusting the position of the particles in multiple steps by applying the potential, It is possible to perform display, color display by containing particles of different colors, or two or more kinds of particles.

  The above microcapsules contain two types of black and white particles, but monochrome (black and white) display can also be realized by using one type of particles and coloring the dispersion medium black.

  That is, as shown in FIG. 7, using a microcapsule in which white particles of titanium oxide are positively charged and dispersed in a black dispersion medium 115, an electric field is applied to the two electrode films 41b and 41d. Thus, when the electrode film 41b is a negative electrode and the electrode film 41d is a positive electrode, the positively charged white particles 113 are drawn to the electrode film 41b side, and the dispersion medium 115 colored in black is necessarily the electrode film of 41d. Since it is pushed down to the side, the part looks white when observed from above the electrode film 41b side. Conversely, when the electrode film 41b is a positive electrode and the electrode film 41d is a negative electrode, the positively charged white particles 113 are drawn toward the electrode film 41d, and the dispersion medium 115 colored black is inevitably generated. Since it is pushed up to the side, when viewed from above the electrode film 41b side, the portion looks black.

  When the microcapsule is driven by the active matrix driving method, the electrode film 41d is independently patterned for each pixel as a pixel electrode, and is provided with a thin film transistor, a signal electrode, and a scanning electrode (not shown), and the electrode film 41b is light transmissive. A transparent common electrode is formed uniformly on the substrate. In this case, if the electrode film 41b is a common electrode, the entire surface has the same potential. Therefore, by controlling the electric field of each address electrode on the electrode film 41d side, the particles in the microcapsule at the electrode position can be moved based on the above principle. A desired image can be displayed.

  Similarly, the electrode film 41d is used as a common electrode (the potential is set to zero), and the electric field of each address electrode on the electrode film 41b side is controlled (giving a positive or negative potential), so that the inside of the microcapsule at the electrode position A desired image may be displayed by moving the particles.

  In the case of time-division driving, the electrode films 41b and 41d are composed of transparent electrodes made of transparent conductors such as line-shaped ITO (Indium Tin Oxide) that are orthogonal to each other, and microcapsules are placed in areas where both electrodes intersect. Form.

Of course, the driving method is not limited to that described above, and an optimal driving method may be selected according to the application.

  Various diameters of the microcapsules can be adopted, but sufficient resolution and responsiveness can be obtained when a diameter of about 40 μm to about 100 μm is employed. The resolution of the displayed image mainly depends on the arrangement (resolution) of the electrode in the electrode film. However, if the diameter of the microcapsule is small, the moving speed of the microcapsule in the dispersion medium increases, and as a result, the response at the time of display is increased. There is an advantage that it is excellent (response speed is fast).

  A paper-like electronic display is made of a flexible material, and patterning of electrodes and the like can be formed on a plastic film by a printing method or a vapor deposition method. The display screen size can be created in any size according to the application and demand. In addition, since it is manufactured using a film, it is a light display medium that is not bulky and can be suitably used as the display medium of the present invention.

In the image display layer 41c, there is no problem in display even if the position of the microcapsules 110 varies slightly. Therefore, it is possible to bend and use it by attaching it to a curved surface.

  Each particle is dispersed in a highly viscous dispersion medium, and once the electric field is applied, the position of the particle does not change even when the power is turned off. In this way, the display image does not disappear even when the display is turned off. It has non-volatility (memory property), so it is only necessary to apply an electric field at the time of initial display or rewriting, and it is necessary for display compared to a normal display device. It requires less power and can save a lot of power.

  Further, in the display 41, there is no problem in display even if the position of the microcapsule 110 is slightly changed. Therefore, by using a material that makes the entire display 41 including the electrode sheets 41b and 41d thin and flexible, it is possible to provide flexibility such as paper.

  Further, since the carbon black of the black particles 114 is the same material as the ink for performing normal printing, it is possible to perform a natural display that is very close to a printed matter on paper.

In FIG. 2, the external view (top view) of the front plate 1 before becoming a display is shown. The front plate 1 of FIG. 2 has a shape having a protruding portion (a portion surrounded by a dotted line in FIG. 2) at an end portion, and an inspection tab portion 18 (described later) and an electrode extraction portion 19 (described later) are formed on the protruding portion. ing.

FIG. 3 shows a cross-sectional view of a portion surrounded by a dotted line in FIG. Since it is not yet bonded, it is in a state with a release material layer 16 and a release film 17 that are unnecessary in the state of the display. In the post-process, the release material layer 16 and the release film 17 are removed and bonded to the back plate by the adhesive material layer 15. The release film 17 includes polyethylene terephthalate as a base material, ITO or aluminum is vapor-deposited as a conductive layer on one side, and a release material layer 16 is formed thereon . An aluminum vapor deposition film is preferable at the point. Laminate in such a direction that the aluminum deposition surface is on the inside. Moreover, as the thickness, 50-300 micrometers is preferable. In FIG. 3, the aluminum layer is denoted by 17a, and the base polyethylene terephthalate is denoted by 17b.

The electrode lead-out portion 19 is formed by inserting a hole-like cut into a part of the protruding portion of the front plate 1 from the release film 17 side, the release film 17 (the aluminum layer 17a and the polyethylene terephthalate base material 17b), the release layer 16, and adhesion. The agent layer 15 and the electronic ink layer 14 are removed so that the transparent electrode 13 is exposed . In the inspection tab portion 18 , the front plate 1 is removed, and only the release film 17 (the aluminum layer 17a and the polyethylene terephthalate substrate 17b) and the release layer 16 are taken out. These are cut out of the outer periphery using a laser, cutter, etc. from a roll or sheet state, and the electrode take-out portion 19 and inspection tab portion 18 are half-cut and then scraped and removed unnecessary portions using a nonwoven fabric or the like. It is formed through. Further, the inspection tab portion 18 is wiped with alcohol for cleaning the surface and removing the peeling layer 16.

  Hereinafter, a probe contact mechanism for driving the front plate of such a display will be described.

  FIG. 1 shows an embodiment of the probe contact mechanism of the present invention. After positioning with a positioning pin or the like so that the centers of the electrode take-out portion 19 and the inspection tab portion 18 of the front plate 1 are respectively located at the centers of the transparent electrode probe 2 and the release film side electrode probe 5, the probe is moved by the spring mechanism 7. When the holder 3 is lowered, the release film side electrode probe 5 breaks the release layer 16 and contacts the conductive layer 17a. Further, the transparent electrode probe 2 contacts the transparent electrode 13. The release film side electrode probe 5 uses a sword-shaped type so as to break the release layer 16 and to contact the conductive layer 17a with certainty. On the other hand, the transparent electrode probe 2 in contact with the transparent electrode 13 has a hemispherical tip so as not to damage the transparent electrode 13.

Both probes are contacted by a spring with an appropriate contact pressure. And the stopper 4 which restrict | limits the height of the slide probe holder 3 is provided so that the contact of the transparent electrode 13 and the peeling film conductive layer 17a may not occur at the end when contacting. The height of the stopper 4 is finely adjusted by using the height adjusting screw 6 so that the contact between the transparent electrode 13 and the release film conductive layer 17a does not occur at the end, and the effective part of the front plate 1 does not peel off. I do.

  FIG. 8 shows a conventional method. The tip of the release film side electrode probe 5 is needle-shaped, and contact may be insufficient unless the contact pressure is increased. Further, at the boundary portion between the inspection tab portion 18 and the base material 12 to the adhesive layer 15, the adhesive layer 15 and the electronic ink layer 14 at the end portion are dropped off in the cutting step and the step of removing the unnecessary portion and cleaning the alcohol, and are transparent. The electrode 13 may protrude. In the alcohol cleaning, the release material layer 16 of the release film also falls off. Here, since the probe holder 3 is lowered by the spring mechanism 7 until it comes into contact with the front plate 1, there is a rare case where the transparent electrode 13 and the conductive layer 17 a of the release film 17 are contacted at the end, and the drive voltage is applied. Even if it did not drive.

It is a contact probe mechanism schematic diagram showing an example of the present invention. It is an external view of the front board before adhesion | attachment. It is sectional drawing of the electrode extraction part and test | inspection tab part of the front plate before adhesion | attachment. It is a display sectional view. It is a schematic sectional drawing of the microcapsule used for a front board. It is a related explanation perspective view of the drive state and display of a microcapsule. FIG. 7 is an explanatory perspective view of a driving state when a microcapsule different from the microcapsule of FIG. 6 is used. It is the conventional contact probe mechanism schematic.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Front plate 2 Transparent electrode probe 3 Probe holder 4 Stopper 5 Release film side electrode probe 6 Height adjustment screw 7 Spring mechanism 12 Base material transparent film 13 Transparent electrode 14 Electronic ink 15 Adhesive layer 16 Release material layer 17a Release film ( Conductive layer)
17b Release film (base film)
41 Display 41b Electrode film 41d Electrode film 41e Base material 41f Color filter 110 Microcapsule 111 Capsule shell 113 White particles 114 Black particles 115 Dispersion medium

Claims (2)

The electrophoretic display device formed by peeling off the release film of the front plate made of at least a substrate, a transparent electrode, a display material, an adhesive layer, and a release film, and bonding the back plate made of at least the substrate, the electrode or the drive element , A probe contact mechanism for inspecting the front plate used when inspecting the front plate before peeling the release film ,
The release film includes a base film, a conductive layer, and a release layer.
The front plate has a protrusion at a part of its end,
The protruding portion is formed with an inspection tab portion only of a release film, and an electrode extraction portion only of a front plate substrate and a transparent electrode,
The front plate inspection probe contact mechanism is:
A transparent electrode probe capable of contacting the electrode take-out part;
A peeling film side electrode probe capable of contacting the inspection tab part;
A probe holder capable of holding the release film side electrode probe and moving up and down, and covering the vicinity of the electrode take-out portion on the substrate side surface of the front plate;
A probe contact mechanism for inspecting a front plate of an electrophoretic display device, comprising: a stopper capable of adjusting and limiting the height of the probe holder and a stopper adjusting screw . A probe contact mechanism for inspecting a front plate according to claim 1,
In the probe holder, contact between the end portion of the front plate and the peeling film does not occur in the inspection tab portion, and peeling between the front plate and the peeling film in the electrode take-out portion occurs inside the protruding portion. A probe contact mechanism for inspecting a front plate of an electrophoretic display device, wherein the position can be adjusted by the stopper and the stopper adjusting screw so as to be disposed at a height that can be accommodated .

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