JP2011000535A - Discharge device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a discharge device capable of uniformly discharging ink while a substrate is passed below a head holding part.SOLUTION: The discharge device has the head holding part 30 and a substrate moving part 20 movable in the y-axial direction. In the head holding part 30, a plurality of heads 32 constitute a head set and a plurality of the head sets constitute a head group. The heads 32 in one head set are arranged so that the intervals among positions where a plurality of the discharge ports 35 are orthographically projected on the x-axis are equal to each other and in one head group, the discharge ports 35 of the other head lot are positioned between two adjacent discharge ports 35 in one head set and the discharge ports in the plurality of the head sets are arranged with the equal interval in a positional relation of the discharge ports orthographically projected on the x-axis. After the substrate 50 in which the width of an area to be discharged is equal to or below the width of the row of the discharge ports 35 included in one head group in the x-axial direction is aligned on the substrate moving part 20, the ink is uniformly discharged on the substrate by discharging the ink while passing the substrate below the head holding part 30.

Description

  The present invention relates to a discharge device.

  With the development of the information society in recent years, the demand for larger liquid crystal display devices has increased, and improvement in productivity has been desired. In a color liquid crystal display device, a color filter is used to color a display image. The color filter is created by arranging inks of three colors R (red), G (green), and B (blue) in a predetermined pattern on a predetermined region on the substrate. An ink jet method is often used for ink ejection.

2. Description of the Related Art Conventionally, many ejection apparatuses have a pedestal that is horizontally placed on a reference surface, a substrate moving unit that can move in one direction on the pedestal, and a head holding unit that can move in a horizontal direction perpendicular to the moving direction. have.
The apparatus described in Patent Document 1 employs a system in which the head holding unit is reciprocated so as to scan on the substrate and ejects the ink. In this system, however, a longer time is required for ejecting ink in proportion to the increase in size of the substrate. In addition, it is difficult to control the ink head in order to land ink at predetermined intervals without unevenness.

  In contrast to the above method, the apparatus described in Patent Document 2 or Patent Document 3 employs a system in which a head holding unit that is stationary with respect to a pedestal holds a number of heads and ejects ink onto a substrate that passes thereunder However, both of the apparatuses described in Patent Document 2 and Patent Document 3 assume a case where an image is printed on a recording medium such as paper, and are more ejected. However, it is inconvenient for manufacturing a liquid crystal display device that requires high accuracy.

Japanese Patent Laid-Open No. 11-248925 Japanese Patent Laid-Open No. 08-174808 JP 11-277734 A

  The present invention was created to solve the above-described disadvantages of the prior art, and the object thereof is to uniformly distribute a large substrate at a predetermined interval while passing under the head holding portion once. Another object of the present invention is to provide a discharge device that can apply ink to the ink.

In order to solve the above-described problems, the present invention provides a pedestal that is stationary with respect to a reference surface, a head set including a plurality of heads each provided with a plurality of discharge ports, and a head group including a plurality of the head sets. And a head holding portion that is fixed to the pedestal and holds the head, and a substrate moving portion that is movable relative to the pedestal in a first direction parallel to the reference plane, from the discharge port A discharge device that discharges a discharge liquid toward a substrate disposed on the substrate moving unit and causes droplets of the discharge liquid to land on the substrate, wherein the plurality of heads in one head set include: The plurality of ejection openings are arranged so that the intervals between the positions projected in parallel on the axis in the second direction parallel to the reference plane and perpendicular to the first direction are equal, and in one head group Orthographically projected on the axis in the second direction In the positional relationship of the discharge ports, the discharge ports of the other head set are positioned between two adjacent discharge ports in one head set, and the discharge ports in the plurality of head sets are It is the discharge apparatus arrange | positioned at equal intervals.
The present invention is a discharge device, and includes a substrate rotation mechanism that rotates the substrate parallel to the reference plane on the substrate moving unit.
The present invention is an ejection device, wherein the plurality of heads are attached to a mounting plate in the head holding portion, and the plurality of heads are joined together by moving the mounting plate in the second direction. And a discharge device having a head moving mechanism that moves in the second direction.
In the present invention, the width in the second direction of the row of the discharge ports included in the head group is the same or larger than the width of the discharge range on the substrate.
The present invention uses the above-described discharge device, and is a plurality of landing positions set on the substrate, and the distance between the centers of the landing positions respectively positioned at both ends of the landing position in one direction on the substrate. Is equal to or less than the distance between the centers of the ejection ports located at both ends of the second direction of the ejection ports in one head group, and the one direction of the landing position is the second direction. Parallel to the direction and between the centers of the discharge ports respectively positioned at both ends of the second direction of the discharge ports in one head group with respect to the second direction. After aligning so that the centers of the landing positions located at both ends of the one-direction array are both positioned, while passing the substrate moving part under the head holding part in the first direction, The discharged liquid is discharged at the landing position. A discharge how to.

Since ink is ejected from a plurality of ejection ports arranged at equal intervals, the ink can be uniformly applied at a predetermined interval, and a high-quality liquid crystal substrate can be obtained.
Since ink is applied while the substrate passes under the head holding portion in one direction, the time required for ejection can be shortened.

Side view of an example of a discharge device that can be used in the present invention The top view of an example of the discharge device which can be used for this invention Schematic diagram of the fixed camera image when the images of the first and second fixed cameras are placed on one plane coordinate. Diagram for explaining the arrangement of the head and the discharge port The figure explaining arrangement | positioning of a head and a discharge port when several discharge ports are located in a staggered arrangement | sequence and the 1 discharge port row | line | column is formed.

A case where the discharge device is used for manufacturing an RGB color filter will be described as an example.
<Discharge device structure>
FIG. 1 shows a side view of a discharge device 10 used in the present invention, and FIG. 2 shows a plan view.

  The discharge device 10 includes a pedestal 70 that is stationary with respect to a horizontal reference plane, a long rail 71, a substrate moving unit 20, and a head holding unit 30. The rail 71 is arranged on the pedestal 70 so that the upper surface thereof is horizontal. The substrate moving unit 20 is disposed on the rail 71. The head holding unit 30 is supported by a column 72 fixed to the base 70 and is fixed at a position higher than the height of the substrate moving unit 20 on the rail 71.

The board moving unit 20 has an on-rail moving mechanism 41. The board moving unit 20 is disposed on the on-rail moving mechanism 41.
The on-rail moving mechanism 41 receives the signal transmitted from the control device 92 and moves the substrate moving unit 20 on the rail 71. For example, a motor is used for the on-rail moving mechanism 41.

  The substrate moving unit 20 is configured to reciprocate under the head holding unit 30 by moving on the rail 71.

Hereinafter, the moving direction of the substrate moving unit 20 moving along the rail 71 is referred to as the y-axis direction (first direction), and the horizontal direction (alignment direction) perpendicular thereto is referred to as the x-axis direction (second direction).
The head holding unit 30 includes an attachment plate 33 and a plurality of heads 32 attached to the attachment plate 33.

FIG. 4 is a schematic diagram for explaining the arrangement of the head 32 and the discharge ports 35.
Each head 32 has a plurality of ejection openings 35. The plurality of discharge ports 35 of one head 32 form a discharge port array side by side on one surface of the head 32.
The discharge ports 35 in one head 32 are arranged at equal intervals in one direction. If the interval is the discharge port interval (distance between the centers of the discharge ports) D, the discharge port intervals D of the heads 32 are also the same. It is the same value.

In the present invention, as long as the plurality of ejection ports 35 of one head 32 are arranged at equal intervals in one direction, it is not necessarily arranged in a straight line. For example, as shown in FIG. Thus, one discharge port array may be formed.
Here, each head 32 is attached to the attachment plate 33 in such an orientation that the one direction is parallel to the x-axis direction.

  In each head 32, the length in the one direction of the head 32 is a length obtained by adding the discharge port interval D to the length of the discharge port array (the distance in the one direction between the centers of the discharge ports 35 at the end). Therefore, when a plurality of heads 32 are arranged in a line parallel to the x axis and the positions on the y axis are the same, the discharge ports 35 located at the end of the discharge port array of one head 32 are arranged. And the distance of the x-axis direction between the discharge ports located in the discharge port row | line | column edge part of an adjacent head will be spaced apart by the distance larger than the discharge port space | interval D. FIG.

  In the present invention, the discharge ports 35 of the adjacent heads are arranged such that the plurality of heads 32 arranged along the x-axis direction have a discharge-port interval D between the discharge ports at the ends of different heads. They are arranged at different positions on the y-axis, the ends of adjacent heads overlap on the x-axis, and each discharge port 35 includes a discharge port interval D on the x-axis, including between the discharge ports of different heads. They are arranged so that they are lined up (so that the intervals between the positions projected on the x-axis are equal).

  In this case, the discharge ports 35 of the plurality of heads 32 arranged along the x-axis can be arranged at two types of positions on the y-axis, and the discharge port arrays of the adjacent heads 32 alternate at two types of positions. Are arranged in a staggered manner so that one head set 38 is formed.

A plurality of sets of head sets 38 are arranged on the mounting plate 33.
A predetermined number n of head sets 38 constitute a head group, and in one head group, two adjacent ones in one head set 38 in the positional relationship of the ejection ports 35 projected on the x-axis. Between the discharge ports 35, the discharge ports 35 of the other head groups are arranged one by one so as to be equally spaced D / n in the x-axis direction.

The head holding unit 30 has an ink tank (not shown), and one ink of the three colors R, G, and B is stored in the ink tank. Each head 32 is connected to an ink tank.
Each ejection port 35 has an ink chamber filled with ink (ejection liquid) inside, and a pressure generator is arranged in each ink chamber. Each pressure generator receives a signal transmitted from the external control device 92, generates a predetermined pressure in the ink chamber, and discharges a predetermined amount of ink from the discharge port 35.

  When the head holding unit 30 has three or more head groups, each head 32 is connected to an ink tank of a different color for each head group, so that one head holding unit 30 can eject ink of three colors. .

The substrate moving unit 20 has a substrate suction plate 24. The substrate suction plate 24 is disposed on the substrate moving unit 20.
The surface of the substrate suction plate 24 facing upward has a suction port (not shown), and the suction port is connected to a vacuum pump (not shown). When the substrate 50 is placed on the substrate suction plate 24 and then evacuated by a vacuum pump, the substrate 50 is vacuum-sucked and held on the substrate suction plate 24.

  On the substrate 50, discharge ranges (landing positions) of R, G, and B colors are defined. The substrate 50 has a grid-like black matrix in a direction parallel to a direction perpendicular to the moving direction, and each landing position is arranged in a region partitioned by the black matrix.

The distance between the centers of the landing positions (the width of the discharged range) located at both ends of the arrangement in the direction perpendicular to the moving direction of the landing positions on one substrate 50 is the discharge port array in one head group. It is formed below the distance in the x-axis direction between the centers of the discharge ports 35 located at both ends (the width in the x-axis direction of the row of the discharge ports 35).
The interval between the landing positions adjacent to each other in the horizontal direction perpendicular to the moving direction of the substrate 50 is the same as the interval between the discharge ports adjacent in the x-axis direction in one head group or an integral multiple of the interval between the discharge ports adjacent in the x-axis direction. It is formed in the length.

<Ink ejection process>
An ink ejection process on the substrate 50 will be described.
It is assumed that the plurality of heads 32 are aligned in advance with respect to the coordinates on the pedestal 70 by an alignment operation in a first alignment process described later. The plurality of heads 32 aligned with the coordinates on the pedestal 70 are collectively referred to as a head array hereinafter.

First, the substrate moving unit 20 is moved to the movement start position and stopped. The substrate 50 is placed on the substrate suction plate 24 so that the line segment connecting the two substrate reference points 51 of the substrate 50 is substantially along the x-axis direction, and vacuum suction is performed to place the substrate 50 on the substrate suction plate 24. Hold by adsorption.
Next, the substrate 50 is moved together with the substrate moving unit 20, and is stopped at a position where the substrate 50 and the head array are aligned. Here, after the substrate 50 and the head array are aligned by the movable camera 21 and the fixed camera 31 as in the alignment operation in the second alignment step described later, the substrate 50 is fixed to the head holding unit 30. Pass below.

  In a state where the alignment of the plurality of heads 32 with respect to the coordinates on the pedestal 70 and the alignment of the substrate 50 and the head array are performed, while the substrate 50 passes under the head holding unit 30, The landing position passes through at least one discharge port 35, and the control device 92 discharges ink from one discharge port 35 to one landing position. One color ink lands.

  When the substrate 50 passes under the head holding unit 30 and arrives at the removal position, ink has landed at each landing position on the substrate 50. After drying at the removal position, the vacuum suction is released and the substrate is released. The substrate 50 is removed from the suction plate 24.

<First alignment process>
In the following, a first alignment process including an origin alignment operation, a head array alignment operation, and a camera reference point position measurement operation of a fixed camera will be described.
The substrate moving unit 20 includes a moving camera 21 and a camera moving mechanism (not shown). The moving camera 21 is disposed at the end of the substrate moving unit 20 in the y-axis direction. The moving camera 21 has a lens at the upper end, and an image taken by the moving camera 21 is subjected to image processing by the observation device 91. For example, a computer is used as the observation device 91.

  When the horizontal direction perpendicular to the moving direction of the substrate moving unit 20 in the coordinate system fixed to the substrate moving unit 20 is referred to as the X direction, the camera moving mechanism receives a signal transmitted from the control device 92 and moves the moving camera. 21 is moved in the X direction. For example, a motor is used for the camera moving mechanism.

<Home position alignment work>
First, the moving camera 21 and the origin are aligned so that the xy coordinates of one point on the image taken by the moving camera 21 can be known.
The external measuring device 93 includes an x-axis direction distance measuring device that measures the movement amount of the moving camera 21 on the x coordinate with a ± sign, and a y-axis direction distance that measures the movement amount on the y coordinate with a ± sign. A measuring device is provided, and when the moving camera 21 moves between two points, the x component and the y component of the vector connecting the start point and the end point of the movement can be known. Since the distance to be measured is signed, the measured value when it moves back and forth and returns to the starting point is zero.
In the field of view that is a range that can be photographed by the mobile camera 21, a movement reference point that is immovable within the field of view is defined.

In the discharge device 10, the origin of the xy coordinates stationary with respect to the pedestal 70 is determined.
When it is assumed that the moving camera 21 is moved and the origin or a perpendicular passing through the origin is captured by the moving camera 21, a perpendicular passing through the origin is photographed, and the image of the origin or the image of the perpendicular passing through the origin is the movement reference. When coincident with the point, the values of the x-axis direction distance measuring device and the y-direction distance measuring device are set to zero.
When the moving camera 21 moves from this state, the xy coordinates of the position overlapping the movement reference point on the image taken by the moving camera 21 can be known.

<Head array alignment work>
Next, the moving camera 21 is positioned under one discharge port 35 by moving the substrate moving unit 20 in the y-axis direction and moving the moving camera 21 in the X direction. When the image of the moving camera 21 is viewed and the movement reference point coincides with the center of the image of the discharge port 35, the xy coordinates of the discharge port 35 are obtained from the value of the measuring device 93.
Such a measurement operation of the xy coordinates of the discharge ports 35 is repeated for all the discharge ports.
A set value is predetermined for the xy coordinates of each discharge port 35. If the measured value of the xy coordinate is different from the set value, it is matched with the set value by the individual head fine adjustment means (fine adjustment screw) of each head 32.

<Fixing camera reference point position measurement work>
The head holding unit 30 has two fixed cameras 31. The two fixed cameras 31 are fixed to one end of the head holding unit 30 in the y-axis direction. Since the fixed camera 31 has a lens at the lower end, the substrate 50 moving under can be photographed.
The arrangement of the two fixed cameras 31 is such that the distance between two camera reference points set for each camera is the same as the distance between the two substrate reference points 51 of the substrate 50. The line segment connecting the reference points is designed to be parallel to the x-axis direction.

However, in reality, the two fixed cameras 31 are arranged at positions deviated from the design values due to mounting errors when being fixed to the mounting plate 33.
The fixed camera 31 has a mark at which the camera reference point on the lens can be photographed by the moving camera 21 from the outside. The moving camera 21 is moved and positioned below one fixed camera 31. When the image of the mark of the fixed camera 31 coincides with the movement reference point on the image taken by the moving camera 21, the xy coordinates of the camera reference point of the fixed camera 31 are measured from the value of the measuring device 93. Similarly, the xy coordinates of the camera reference point of the other fixed camera are measured and stored.

<Second alignment step>
Hereinafter, a second alignment process for performing the alignment operation between the substrate 50 and the head array will be described.
The image captured by the fixed camera 31 is subjected to image processing by the observation device 91 so that the coordinates of a desired position in the image can be known.
First, the substrate moving unit 20 is moved in the y-axis direction so that the two substrate reference points 51 of the substrate 50 are positioned one by one under the two fixed cameras 31.

FIG. 3 shows a schematic diagram 80 of fixed camera images when the images 85a and 85b of the first and second fixed cameras are placed on one plane coordinate.
Reference numerals 81a and 81b in FIG. 3 indicate camera reference points of the first and second fixed cameras, and reference numerals 82a and 82b indicate respective design values (first and second design values). Reference numerals 83a and 83b indicate images (first and second substrate reference points) of the substrate reference point 51 taken by the first and second fixed cameras, respectively.

The observation device 91 determines the value of the angle θ formed by the straight line passing through the two points of the first and second design values 82a and 82b and the straight line passing through the two points of the first and second substrate reference points 83a and 83b. It is obtained by calculation from the coordinates of each point and transmitted to the control device 92.
The substrate moving unit 20 has a rotation moving mechanism 42. The rotational movement mechanism 42 receives the signal transmitted from the control device 92 and moves the substrate suction plate 24 by rotating the substrate at an angle horizontally around its central axis. At the same time, the substrate 50 held on the substrate suction plate 24 is also horizontally rotated. For the rotational movement mechanism 42, for example, an air spindle that is rotationally driven by compressed air is used.

When the control device 92 receives the value of the angle θ formed by the two straight lines from the observation device 91, the control device 92 transmits a control signal for rotating the angle θ to the rotational movement mechanism 42. When the substrate 50 is rotated by an angle θ, the two straight lines are in a parallel positional relationship.
The two substrate reference points 51 after the rotational movement are subjected to image processing by the observation device 91, and the respective xy coordinates are known.

Since the relative positions of the two substrate reference points 51 and the respective landing positions on the substrate 50 are set in advance, if the xy coordinates of the substrate reference point 51 are known, the xy coordinates of the respective landing positions can be known.
Since each discharge port 35 is aligned by the first alignment process described above, the xy coordinates are known.

The head holding unit 30 has a head moving mechanism (not shown). The head moving mechanism receives a signal transmitted from the control device 92 and moves the mounting plate 33 in the x-axis direction. At the same time, all the heads 32 are moved in the x-axis direction while the relative positions of the heads are maintained. For example, a motor is used for the head moving device.
All the heads are moved by a predetermined distance in the x-axis direction by the head moving mechanism so that the x-coordinates of the predetermined discharge ports 35 coincide with the x-coordinates of the predetermined landing positions.

The second alignment process is completed by the above procedure. In this state, there is no x-coordinate difference between the predetermined discharge port 35 and the predetermined landing position, and the y-coordinate distance difference is known.
The present invention is not limited to the manufacture of RGB color filters, and includes, for example, the manufacture of EL (electroluminescence) display elements and liquid crystal display devices.

DESCRIPTION OF SYMBOLS 10 ... Discharge device 20 ... Board | substrate moving part 30 ... Head holding part 32 ... Head 35 ... Discharge port 38 ... Head assembly 50 ... Board | substrate 70 ... Base

Claims (5)

A pedestal placed stationary with respect to the reference plane;
A head set having a plurality of heads each having a plurality of ejection openings;
A head group having a plurality of the head sets;
A head holding part fixed to the base and holding the head;
A substrate moving part movable in a first direction parallel to the reference plane with respect to the pedestal;
A discharge device that discharges a discharge liquid from the discharge port toward a substrate disposed on the substrate moving unit, and causes droplets of the discharge liquid to land on the substrate,
A plurality of the heads in one head set have equal intervals between positions where the plurality of ejection ports are orthographically projected on an axis in a second direction parallel to the reference plane and perpendicular to the first direction. Arranged to be
In one head group, in the positional relationship of the ejection ports that are orthographically projected on the axis in the second direction, between the two adjacent ejection ports in one head set, the other An ejection device in which the ejection ports of a head set are positioned and the ejection ports in the plurality of head groups are arranged at equal intervals.   The discharge apparatus according to claim 1, further comprising a substrate rotation mechanism configured to rotate the substrate parallel to the reference plane on the substrate moving unit. The plurality of heads are attached to a mounting plate in the head holding portion,
The ejection device according to claim 1, further comprising a head moving mechanism that moves the plurality of heads together in the second direction by moving the mounting plate in the second direction.   4. The ejection according to claim 1, wherein a width of the ejection port array included in the head group in the second direction is the same as or larger than a width of an ejection range on the substrate. 5. apparatus. Using the discharge device according to any one of claims 1 to 4,
A plurality of landing positions set on the substrate, and the distances between the centers of the landing positions respectively positioned at both ends of the landing position in one direction on the substrate are the same in one head group. Is less than or equal to the distance between the centers of the discharge ports located at both ends of the second direction of the discharge ports,
The one direction of the landing position is parallel to the second direction, and is positioned at each end of the second direction of the ejection ports in one head group with respect to the second direction. After aligning the center of the landing positions located at both ends of the unidirectional arrangement of the landing positions between the centers of the discharge ports to be positioned,
An ejection method for ejecting the ejection liquid to the landing position while passing the substrate moving unit under the head holding unit in the first direction.

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