WO2009099051A1

WO2009099051A1 - Application device and application method

Info

Publication number: WO2009099051A1
Application number: PCT/JP2009/051765
Authority: WO
Inventors: Takashi Iwade; Junichi Uehara; Shigeru Tohno; Satoshi Tomoeda
Original assignee: Toray Engineering Co., Ltd.
Priority date: 2008-02-04
Filing date: 2009-02-03
Publication date: 2009-08-13
Also published as: CN101932958B; CN101932958A; KR20100119857A; JP2009211058A; TW200950889A

Abstract

Provided are an application device and application method which use a small number of nozzles and do not produce irregularities at borders. An application device for manufacturing colour filters by applying a number (N) of primary colour inks using a plurality of inkjet heads (51) is characterized in that head modules (52) consist of one or more inkjet heads (51) for supplying ink of the same colour, said head modules (52) being arranged with a pitch P in the scanning direction such that at least the two ends of the head modules (52) in the ink ejection width direction are adjacent or located one on top of the other. The head modules (52) of the head block (50) are arranged in continuous rows of length L at a right angle to the scanning direction, ink of different colours is supplied successively to the head modules (52) of said head block (50), and L is the following equation with respect to the application width W which is necessary for the colour filter. [Equation] L ≥ W + (N - 1) x P (N = 1, 2, 3..)

Description

Coating apparatus and coating method

The present invention relates to a coating apparatus and a coating method. Specifically, a coating apparatus and a coating that discharge a predetermined amount of ink from a plurality of inkjet nozzles at a predetermined position while relatively moving (scanning) the plurality of inkjet nozzles and a substrate to be coated facing each other. The method is particularly suitable for application to a color filter manufacturing apparatus.

The color liquid crystal display is composed of a color filter, a TFT array substrate, and the like. Among them, the color filter is formed by regularly dividing each pixel bordered by a grid-like black matrix on a glass substrate into three colors of R (red), G (green), and B (blue). Thus, it is a member that forms the center of color formation of a color liquid crystal display.

This color filter is usually 1) after forming a black photoresist material coating film on a glass substrate, and then processing the black coating film into a grid by photolithography (formation of a grid-like black matrix), 2) Once the R coating film is formed on the entire surface, the R coating film is left only on the R pixels between the lattices by photolithography (R pixel formation). After the coating films of G and G are formed on the entire surface, the B and G coating films are left only on the B and G pixels (B and G pixel formation). In forming the R, G, and B pixels by the above-described photolithography method, many processes such as R, G, and B whole surface coating film formation, exposure, and development are required.

In recent years, in order to simplify this, only R, G, and B inks are directly applied to the pixel portion formed by a black matrix lattice by an inkjet head to form R, G, and B color pixels. The technique has come to be industrially performed (for example, refer to Patent Document 1). This method of forming R, G, and B pixels using an inkjet head does not require steps such as exposure and development, and uses only an amount of ink necessary for color pixel formation, thereby enabling significant cost reduction in color filter manufacturing. (See

Patent Documents

1, 2, 3, and 4).

This patent document 1 discloses specifications that are optimized for the properties of the inks of R, G, and B inks by inkjet.

Patent documents

2 and 3 disclose a color filter that uses an inkjet head. A manufacturing apparatus and a manufacturing method are disclosed.

As an example of main components of a color filter manufacturing apparatus using an inkjet head, an inkjet head having a plurality of inkjet nozzles, a holding stage that holds a substrate, and a moving unit that relatively moves the inkjet head and the holding stage Some have This apparatus discharges a predetermined amount of ink from a plurality of inkjet nozzles at a predetermined timing while relatively moving (scanning) in the horizontal direction X in a state where the plurality of inkjet nozzles and the substrate are opposed to each other. A color filter is formed.

Since the color filter generally has a small pixel size of about 100 microns, it is necessary to increase the resolution (array density) of the inkjet head in the color filter manufacturing apparatus. In order to improve production efficiency, the time required for coating is preferably as short as possible.

Therefore, in Patent Document 4, as shown in FIG. 10, a plurality of (two in the figure) inkjet heads 510 are arranged in series in the scan direction X to configure the head 520 to increase the resolution (array density). Yes. In addition, by arranging a plurality of heads 520 in parallel in the direction Y orthogonal to the scan direction X, the number of scans of the inkjet head 510 is reduced. As a result, the coating time required for coating all the portions to be coated of the substrate K is shortened.

In the head arrangement of the color filter manufacturing apparatus, the heads 520 are arranged in a staggered manner as shown in FIG. This is due to the following reason. That is, since the head 520 has a width of the casing 52A larger than the arrangement width W0 of the inkjet nozzles 540, there is a space T between the end portion 512 of the casing 52A and the end portion 511 of the nozzle group. For this reason, when scanning in the X direction with a plurality of head modules 520 arranged in a line in the Y direction, a nozzle non-passing region in which the ink jet nozzle 540 does not pass at all is formed due to the presence of the interval T. The width of the nozzle non-passing region is twice the width T. Therefore, the heads 520 are arranged in a staggered manner to cancel the nozzle non-passing area.

In video equipment such as liquid crystal displays, there is always a demand for high-definition and high-definition video. On the other hand, the size of video equipment is also increasing, and it is necessary to manufacture color filters for large-size video equipment. Therefore, there is an increasing demand for a reliable and low-cost apparatus that can accurately apply ink to fine pixels over the entire effective pixels of the color filter.

Therefore, in Patent Document 2, a liquid droplet discharge head in which nozzle rows are formed is linearly arranged to form a head row, and a plurality of head rows are connected in parallel so that the ends of the liquid droplet discharge heads are connected to each other. Or the configuration of one nozzle row is not linear, and the end portions of the droplet discharge heads are arranged so as to overlap each other to form a head unit in which a plurality of the droplet discharge heads are combined to form ink. It is said that color unevenness and stripe unevenness are avoided by applying.

On the other hand, in the color filter manufacturing method and apparatus of Patent Document 3, the positional accuracy by accurately ejecting ink onto display dots as filter elements is specified by specifying the nozzle pitch and the arrangement and movement amount between a plurality of heads. The problem is solved. In addition, when the filter material (ink) is ejected by one head formed by a plurality of nozzles, the occurrence of characteristic variations (ejection distribution characteristics) in the ink ejection amount for each nozzle is detected. It is said that the problem has been solved by correcting the amount by optimizing the amount and overcoming the two problems of vertical streaks due to variations in light transmission in the main scanning direction of the filter element.

JP 2006-209140 A Japanese Patent No. 3925525 JP 2003-84125 A Japanese Patent Application No. 2006-134514

However, as in Patent Document 3,
A method of applying ink to a color filter substrate by moving the head several times in the sub-scanning direction by repeatedly moving the head in the main scanning direction by applying the ink to the color filter substrate by moving the head in the main scanning direction. When producing color filters for large video equipment as described above, the head scans the area of the color filter substrate where ink is applied and the head scans and applies ink after the next time. There is a difference in the time for applying the ink to the adjacent application region between the adjacent regions of the color filter substrate (see FIG. 25 of Patent Document 3).

The present inventors indicate that a difference occurs in the surface shape after drying of the ink applied to the pixel due to this time difference, and the color filter is used as an optical component in the ink application method to the pixel by the ink jet method. In particular, when used for high-definition video equipment, it has been found that “streak unevenness” is visible and quality is reduced.

When the ink is applied to the entire area of the effective pixels of the color filter by moving (scanning) the head divided multiple times in the direction orthogonal to the scanning direction and the dried ink surface is observed in cross section The cross-sectional shape of the ink surface of the pixel applied in a divided manner is different from the cross-sectional shape of the ink surface of the pixel where the periphery of the other pixel is simultaneously applied with ink. When observed with reflected light, streaks generated vertically in the direction of movement of the inkjet head during coating can be confirmed.

This vertical streak causes the ink at the end of the applied region generated at the boundary between the coated region and the uncoated region to dry faster on the uncoated region side. Since the density of the ink on the non-applied region side becomes high, the cross-sectional shape after drying becomes thicker on the non-applied region side.

Furthermore, it demonstrates in detail using FIG. Here, FIG. 14 is a diagram showing a case where the head 101 is applied by scanning twice with respect to the required application width W of the color filter substrate 100 (also referred to as a substrate). That is, ink is applied to a plurality of pixels arranged in the Y direction by ejecting ink from the head 101, and ink is sequentially applied to the plurality of pixels arranged in the X direction by scanning the head 101 in the X direction. Is applied. In this way, the head 101 performs the first scan to apply the left side of the necessary application width W (referred to as region A) (FIG. 14B), and then performs the second scan to perform the required application. The right side of width W (referred to as region B) is applied (FIG. 14C). The color filter substrate 100 is a base material from which a product color filter is obtained by being finally cut, and a plurality of required application widths W from one color filter substrate 100 are obtained. A color filter can be obtained.

As shown in FIG. 14, in the state (FIG. 14 (b)) in which the region A is applied by the first scanning of the head 101 from the color filter substrate 100 (FIG. 14 (a)) before application, the region The dry state is different between the pixel at the center of A and the pixel at the end of region A. That is, since the pixel in the central portion of the region A has pixels around which ink is applied, the amount of ink evaporation (drying speed) is constant throughout the area. Accordingly, the pixels in the central portion themselves are dried at a constant drying speed as a whole, and the dried ink thickness when the attention is paid to one pixel is dried in a uniform state.

However, the pixel at the end of the region A, that is, the pixel adjacent to the boundary α between the region A and the region B is a pixel on the region B side, although there are pixels to which the ink is applied on the region A side. The ink has not been applied yet. Therefore, the amount of ink evaporation by other pixels is large on the region A side of the pixel at the end of the region A, and there is no ink evaporation amount on the region B side. A phenomenon occurs in which the drying speed is slow in a portion close to, and the drying speed is fast in a portion close to region B. Therefore, the pixel at the end of the area A after drying is dried in a state where the ink is thick on the area A side and the ink is thin on the area B side. Such pixels are formed in a line along the vicinity of the boundary α. Similarly, in the region B, pixels in which the ink is thin on the region A side and the ink is thick on the region B side are formed along the vicinity of the boundary α.
Therefore, when used as a product color filter in such a state, due to the difference in the thickness of the ink, the rate of light transmission near the boundary α is larger than the other parts, and this is visually recognized as “streaks unevenness”. Problem arises.

On the other hand, in the configuration of the apparatus of Patent Document 2, in order to prevent such vertical streaks due to the difference in transmitted light amount or the difference in external light reflection, the moving direction of the inkjet head 101 is prevented so that the above-described boundary portion does not occur. It is necessary to prepare nozzles having a necessary arrangement density over the entire width of the color filter in the direction orthogonal to the width of the color filter. That is, the ejection width of the head 101 is provided to extend to the required application width W of the color filter substrate 100 (see Patent Document 2, FIG. 2), and the application is completed by scanning the head 101 once with respect to the required application width W. Let As a result, it is possible to eliminate the cause of the boundary α becoming “streak unevenness”. However, in such a configuration, as the head 101 becomes longer, a large amount of expensive discharge nozzles are required, and thus there is a problem that the entire apparatus becomes expensive. Further, since the color filter is composed of at least three colors of red (R), green (G), and blue (B), the total number of nozzles is tripled, and there is a problem that the number becomes enormous.

The present invention has been made in view of the above-described problems, and provides a coating apparatus and a coating method that do not cause unevenness at the boundary with a small number of nozzles.

In order to solve the above-described problems, a coating apparatus according to the present invention includes a head block that is provided with a plurality of head modules that eject ink of a single color and can apply N-color (N = 1, 2, 3,...) Ink. A coating apparatus for producing a color filter by ejecting N color ink from the head block while relatively moving the head block and the substrate in a scanning direction. The head modules are arranged with a length L at a predetermined pitch P in a direction orthogonal to the scan direction at a predetermined cycle by sequentially changing the colors of the N colors, and this length L and a color filter are formed. The relationship with the required coating width W in the direction orthogonal to the scanning direction in the color filter forming region is L ≧ W + (N−1) × P (N = 1, 2, 3,...)
It is characterized by satisfying.

According to this configuration, the head module is provided at a predetermined pitch P in a direction orthogonal to the scan direction at a predetermined cycle by sequentially changing the colors of each of the N colors. In this scanning, the same color or different color inks can be continuously applied in the direction orthogonal to the scanning direction. Therefore, when viewed with respect to one applied pixel, since the applied pixel exists in a position adjacent to the direction orthogonal to the scan direction in one scan, the dried state of the applied pixel is almost the same. It can be made uniform. That is, although the applied pixels are formed continuously in the scan direction as in the conventional case, the difference in drying speed is not applied to the pixels adjacent to the direction orthogonal to the scan direction until the next scan. It was difficult to make the dried state uniform, but in the present invention, pixels of the same color or different colors exist in almost the same pattern around the applied pixels in one scan. As a result, the amount of ink evaporated from the surrounding pixels becomes substantially the same, and the drying speed of one applied pixel becomes substantially constant. Thereby, the dried state of the applied pixels can be made substantially uniform. Since the head module is provided longer than the required coating width W by (N−1) pitches or more, the dry state can be made substantially uniform over the required coating width W. Therefore, it is possible to suppress the formation of “streaks” due to the dry state.

Further, since the head modules are provided with the N colors sequentially changed, it is not necessary to provide a single-color head module over the required coating width W as in the prior art, and the total number of head modules can be reduced.
Further, the plurality of head modules are arranged in a staircase by arranging head modules arranged in a direction orthogonal to the scanning direction at a pitch P, and arranging these head modules adjacent to each other in the scanning direction. A group of head modules arranged side by side may be formed, and the head module group may be repeatedly arranged in a direction orthogonal to the scanning direction on the head block.

According to this configuration, since the number of head modules can be reduced as compared with the case where the head modules are continuously arranged in a line in a direction orthogonal to the scanning direction, the cost of the apparatus can be reduced.

Further, the head module is provided with a plurality of ink jet nozzles for ejecting ink, and the head modules arranged in a direction orthogonal to the scan direction are arranged so that the ink ejection area of the ink jet nozzle is viewed from the scan direction. It is good also as a structure arrange | positioned in the overlapping state.

According to this configuration, since the ink discharge region can be continued continuously over the length L, the ink can be applied to the pixels without application unevenness over the required application width W.

In order to solve the above problems, the coating method according to the present invention provides a head capable of applying N color (N = 1, 2, 3,...) Ink by providing a plurality of head modules that eject single color ink. A coating method for manufacturing a color filter by ejecting N color ink from the head block while relatively moving the head block and the substrate in a scanning direction. The head module is arranged with a length L at a predetermined pitch P in a direction orthogonal to the scanning direction at a predetermined cycle by sequentially changing the colors of each of the N colors. The relationship between the required coating width W in the direction orthogonal to the scanning direction in the color filter forming region to be formed is L ≧ W + (N−1) × P (N = 1, 2, 3,...)
By ejecting ink from the head module while moving the head block and the substrate relative to each other in the scanning direction, pixels coated with different color inks are orthogonal to the scanning direction. And a scanning process in which coating is performed so that N colors are sequentially changed over the necessary coating width W at positions adjacent to each other in the scanning direction.

According to this configuration, the dry state of the pixels can be made substantially uniform by having the scanning step. That is, when ink is ejected from the head module of the head block having the above relationship, pixels applied in a direction perpendicular to the scan direction and in a position adjacent to the scan direction exist in one scan. Applied. As a result, the same color or different color pixels exist in the same pattern around the applied pixel in one scan, and the amount of ink evaporation from the surrounding pixels becomes substantially the same. The dried state of the applied pixels can be made substantially uniform. Therefore, compared to the conventional application method in which the pixel adjacent to the applied pixel is not applied until the next scan, the dry state can be made uniform over the color filter region, resulting in the dry state. The formation of “streaks” can be suppressed.

In addition, by sequentially repeating the scanning step, the shifting step of moving the head block in the direction orthogonal to the scanning direction, and the scanning step again, the pixels to which the ink of the specific color is applied in the previous scanning step are applied. The adjacent pixels may be formed by applying the same color ink in the next scanning step so that the pixels to which the same color ink is applied extend in a direction perpendicular to the scan direction.
According to this configuration, it is possible to form a color filter in which pixels applied with the same color ink extend in a direction orthogonal to the scan direction in a substantially uniform dry state.

In order to achieve the above object, the present invention provides a coating apparatus for manufacturing a color filter by applying a number of primary colors (N) with a plurality of inkjet heads (51).
One or more inkjet heads (51) for supplying ink of the same color constitute a head module (52), and at least both ends of the ink discharge width of the head module (52) are adjacent or overlap each other. Are arranged in the scanning direction at a pitch P, and a head block (50) in which these head modules (52) are continuously arranged in the direction orthogonal to the scanning direction by a length L is formed, and the head of the head block (50) A coating apparatus which supplies ink by changing the color sequentially for each module (52), and L is the following formula with respect to the required coating width W of the color filter.
[Formula 1] L ≧ W + (N−1) × P
Also, every scan, the pitch P is shifted in the direction orthogonal to the scan direction, and scanning is performed N times.

Further, the arrangement pitch P of the modules (52) is set to the following formula.
[Formula 2] P ≦ (1 / N) × W
In addition, the reference numerals in parentheses attached to each component in each column of “Claims” and “Means for Solving the Problems” indicate correspondence with specific means described in the embodiments described later. is there.

According to the present invention, in the color filter that is the object to be coated, the transmitted light amount, which is the main optical characteristic, is averaged over the entire effective pixel, and the surface shape after the ink is dried is also flattened, and the color filter is achieved. Provided are a coating apparatus and a coating method capable of manufacturing a high-quality color filter with a small-sized apparatus in which external light reflection on the surface of the filter is uniform over the entire surface and there is no partial uneven distribution of brightness and darkness.

Further, the required number of nozzles for ejecting each color is (1 / N) or (1 / N + 1) with respect to the necessary application width “W”, where the number of inkjet nozzles 54 that eject ink of the number of colors to be applied is required. Therefore, it is sufficient to apply the width having the above value, so that the equipment cost as a coating apparatus can be suppressed.

It is a perspective view which shows the color filter manufacturing apparatus which concerns on this invention. It is a top view which shows the principal part of the color filter manufacturing apparatus which concerns on this invention. FIG. 3 is a schematic plan view illustrating a part of an ink discharge unit. It is a plane schematic diagram of a head block. It is a top view of the glass substrate used as the formation object of a color filter. It is a flowchart which shows the operation | movement outline | summary of the color filter manufacturing apparatus which concerns on this invention. It is a flowchart which shows the application | coating operation | movement in FIG. 6 in detail. It is a figure for demonstrating the scanning operation | movement at the time of application | coating. The figure for demonstrating the ink application state to the pixel by one scan. It is the plane schematic diagram of the conventional head block. The figure which shows the measurement data of the stylus type height meter of the ink surface which is applied to the pixel The figure which shows head module arrangement | positioning of the manufacturing apparatus by the ink of four colors The figure for demonstrating the ink application state to the pixel in a direction different from FIG. It is the schematic which shows the conventional coating method. It is a figure which shows the application state when the 1st scanning process is complete | finished. It is a figure which shows the application state when the 2nd scanning process is complete | finished. It is a figure which shows the application state when the 3rd scanning process is complete | finished.

Explanation of symbols

1 Color filter manufacturing equipment (coating equipment)
45 Second linear motor (head block shift means)
50 Head Block 51 Inkjet Head 52 Head Module 54 Inkjet Nozzle gs Pixel (Applicable Location)
K glass substrate (substrate)
X direction (scan direction)
Y direction (scan orthogonal direction)
W Required coating width A Color filter formation area

Hereinafter, an apparatus and a method for producing a color filter using three colors of red (R) green (G) blue (B) ink will be described with reference to the accompanying drawings.
FIG. 1 is a perspective view illustrating a color filter manufacturing apparatus according to the present invention, FIG. 2 is a plan view illustrating a main part of the color filter manufacturing apparatus according to the present invention, and FIG. 3 is a schematic plan view illustrating a part of an ink ejection unit. FIG. 4 is a schematic plan view of the head block 50. In each of these drawings, the three axes of the orthogonal coordinate system are X, Y, and Z, the XY plane is the horizontal plane, the Z-axis direction is the vertical direction, and the rotation direction around the vertical axis is the θ direction. Further, the operation from the upstream to the downstream in FIG. 1 is the forward movement, and the operation from the downstream to the upstream is the backward movement.

In the present embodiment, the X direction of the orthogonal coordinate system is a direction in which an application gantry 4 (described later) travels (scan direction), and the Y direction orthogonal to the direction is the direction in which the ink discharge unit 5 travels (shift direction). .

As shown in FIG. 1, a color filter manufacturing apparatus 1 (coating apparatus of the present invention) according to the present invention includes a machine base 2, an adsorption stage 3, a coating gantry 4, an ink discharge unit 5, a camera gantry 6, an alignment camera 7, A scan camera 8, a substrate transfer robot 9, and a control device 10 are provided.

The machine base 2 functions as a pedestal that movably supports the main components (the suction stage 3, the coating gantry 4, and the camera gantry 6) of the color filter manufacturing apparatus 1.

As shown in FIG. 2, the suction stage 3 has a mounting surface 31 on which a glass substrate K (also simply referred to as a substrate K) to be coated with color ink can be mounted with sufficient flatness. A plurality of vacuum suction holes 32 and a plurality of lift pin holes 33 are formed in the mounting surface 31. The vacuum suction hole 32 is connected to a suction pump through a pipe and a three-way valve. From the lift pin hole 33, a lift pin 34 for supporting the glass substrate K can be projected and retracted. The suction stage 3 can be driven to rotate in the θ direction by a stage rotation driving means (not shown).

Note that the color filter is formed on a part of the substrate K, and in this embodiment, one color filter is formed on one substrate K. At that time, ink is applied to a predetermined region of the substrate K on which the color filter is formed, that is, the color filter formation region R. In this embodiment, the Y-direction dimension of the color filter formation region R is set as the required application width W. (See FIGS. 2 and 15 to 17).

The coating gantry 4 has a portal shape that can span the suction stage 3. The coating gantry 4 has at least two struts 41 that are erected with a width interval between the suction stages 3 and between the two struts 41. And an erected horizontal frame portion 42. The pair of first linear motors 43 are supported on the machine base 2 so as to be able to travel in the X-axis direction while straddling the suction stage 3. The pair of first linear motors 43 are attached to both sides in the Y-axis direction of the machine base 2 so as to be parallel to each other along the X-axis.

The horizontal frame portion 42 can be moved up and down in the Z direction by servo motor mechanisms 44 respectively provided on the two support column portions 41. The servo motor mechanism 44 can be constituted by, for example, a linear motor provided along the Z-axis direction. Alternatively, a ball screw shaft disposed along the Z-axis direction, a rotation servo motor that drives the ball screw shaft to rotate forward and backward about its axis, and a ball screw shaft that is engaged with the ball screw shaft to move forward and backward in the Z-axis direction. You may comprise with a ball nut etc. The horizontal frame portion 42 is provided with the ink discharge portion 5 so that the second linear motor 45 can travel in the Y-axis direction. The second linear motor 45 is attached to the horizontal frame portion 42 along the longitudinal direction (Y direction).

The head module 52 mounted on the ink discharge unit 5 is arranged in the Y direction as shown in FIGS. Each head module 52 includes an inkjet head 51 that is arranged in D stages (D = 5 in this figure) in the X direction as shown in FIG. FIG. 3 shows only a part of the ink discharge unit 5, that is, the red head module 52.

Each inkjet head 51 is composed of J (J = 10 in this figure) inkjet nozzles 54 arranged at equal intervals in the Y direction, and the ink discharge width is H. The J inkjet nozzles 54 can discharge the same color. For example, red ink is ejected from the inkjet nozzles 54 corresponding to the red ink head module 52.

The head module (52) is arranged in the scanning direction at a pitch P so that at least both ends of the ink ejection width of the head module (52) are adjacent or overlap. A head block (50) in which these head modules (52) are arranged in a length L continuously in a direction orthogonal to the scanning direction is configured, and the color is sequentially changed for each head module (52) of the head block (50). Supply ink.

More specifically, the head block 50 is provided with a plurality of head modules 52. In the present embodiment, as shown in FIG. 4, all the head modules 52 are arranged side by side at a pitch P in the Y direction. Has been. Specifically, along the X direction, three head modules 52 are arranged in a staircase pattern, and a plurality of structural units arranged in a staircase pattern are repeatedly arranged in the Y direction as a head module group. .

This head module group is configured as one head module 52 that ejects red (R), green (G), and blue (B) ink along the X direction. They are adjacent to each other in the X direction and arranged at a pitch P in the Y direction. In other words, the adjacent head modules 52 are arranged side by side in a stepped manner by being arranged apart in the X direction and the Y direction. By repeatedly arranging the head module group in the Y direction, when viewed in the Y direction, the head modules 52 are arranged in a predetermined cycle (in this embodiment, a three-color cycle) by sequentially changing the colors of the three colors. Note that 52 (R), 52 (G), and 52 (B) in FIG. 4 indicate the head modules 52 that discharge red, green, and blue inks, respectively.

The head module 52 includes a plurality of ink jet heads 51 that eject ink of a single color, and the head module 52 alone can apply a single color of ink. That is, the inkjet head 51 has a plurality of inkjet nozzles 54, and single color ink is ejected from the inkjet nozzles 54. The inkjet nozzles 54 are arranged in the Y direction, and an area in the Y direction where ink can be ejected by the inkjet nozzle 54 is an ink ejection area. In the present embodiment, the pitch P is set such that the ink ejection regions overlap when viewed from the X direction. As a result, all the head modules 52 adjacent to each other in the Y direction (for example, the head module 52 that discharges red ink and the head module 52 that discharges green ink) are arranged in a state where the discharge regions overlap when viewed from the X direction. ing. The head modules 52 adjacent in the Y direction are head modules 52 that are shifted by one in the Y direction. That is, for example, in FIG. 4, the head module 52 adjacent to the red head module 52 (upper left in the figure) is the green head module 52.

Here, as shown in FIG. 4, the plurality of head modules 52 are arranged with a length L at a pitch P in this embodiment.
And with respect to the required application | coating width W of a color filter, L is following Formula.
[Formula 1] L ≧ W + (N−1) × P (N = 1, 2, 3,...)
The arrangement pitch P of the head modules (52) is given by the following equation.
[Formula 2] P ≦ (1 / N) × W (N = 1, 2, 3,...)

That is, for a color filter having a certain vertical and horizontal size, the required coating width in the direction orthogonal to the scanning direction of the head block 50 for coating when the color filter is mounted on the coating apparatus is as shown in FIG. In the case of “W”, the number “N” of inks to be applied is 3, and the ink discharge widths of the respective colors are shifted by a pitch “P” so as to be adjacent or overlapped with each other. The head block 50 is arranged by a length “L” that is equal to or greater than (W + 2P).

That is, the overall Y-direction dimension of the plurality of head modules 52 provided in the head block 50 is set to be longer than the necessary coating width W by 2P. When the head block 50 and the substrate K face each other, the two head modules 52 is located outside the required coating width W in the Y direction.

Further, the arrangement pitch “P” of the head modules 52 of each color is set to 1 / N of the required coating width “W”, that is, 1/3 or less, more preferably so that the number of inkjet nozzles 54 provided in the head block 50 is reduced. The width is less than the width of the inkjet head. When the pitch P is the same as the width of the ink-jet head, the width of the head module is one ink-jet head, and the number of ink-jet heads mounted on the head block is the minimum.

Similarly to the coating gantry 4, the camera gantry 6 mounted on the machine base 2 has a portal shape with a size that can straddle the suction stage 3, and is provided with two at least spaced apart by the width of the suction stage 3. And a horizontal frame 62 constructed between the two support columns 61. The pair of first linear motors 43 are supported on the machine base 2 so as to be able to travel in the X-axis direction while straddling the suction stage 3.

The horizontal frame 62 is provided with two alignment cameras 7 so that the third linear motor 63 can travel in the Y-axis direction. The substrate transport robot 9 for loading and unloading the glass base material K on the machine base 2 includes a motor 91, an arm 92, and a movable support base 93. The movable support base 93 has a fork shape on which the glass substrate K can be placed, and is configured to be movable in each direction of XYZθ through an arm 92 by driving a motor 91.

The control device 10 of this apparatus is configured to cause the color filter manufacturing apparatus 1 to perform a series of operations. Specifically, when the inkjet nozzle 54 of the head module 52 is positioned on a predetermined pixel gs of the substrate K, it can be appropriately controlled so that ink is ejected from the inkjet nozzle 54.

Next, the operation of the color filter manufacturing apparatus 1 configured as described above will be described with reference to FIGS. FIG. 5 is a plan view of a glass substrate on which a color filter is to be formed, FIG. 6 is a flowchart showing an outline of the operation of the color filter manufacturing apparatus according to the present invention, FIG. 7 is a flowchart showing in detail the application operation in FIG. FIG. 9 is a diagram for explaining a scanning operation at the time of application, and FIG. 9 is a diagram for explaining an ink application state to the pixel gs by one scanning operation.

As shown in FIG. 5, a black matrix BM, which is a color ink application section, and an alignment mark M1 are formed in advance on the surface of the glass substrate K to be formed with a color filter. “R”, “G”, and “B” in the figure indicate the pixels gs corresponding to the respective target colors of red, green, and blue. The color filter manufacturing apparatus 1 is in the following initial state. That is, the suction stage 3 is in a non-adsorption state, the coating gantry 4 is in the most upstream position, the ink ejection unit 5 is in a non-ejection state, and the camera gantry 6 is in the most downstream position. A glass substrate K is placed on the movable support base 93 in the substrate transport robot 9.

[Glass substrate loading (step S1)]
First, the substrate transfer robot 9 drives and controls the movable support base 93 so that the glass substrate K is located directly above the suction stage 3. Subsequently, the lift pin 34 protrudes from the lift pin hole 33 and is raised to the uppermost position as the glass receiving position. Subsequently, the substrate transfer robot 9 gradually lowers the movable support base 93 and places the glass substrate K on the tip of the lift pin 34. After placing the glass substrate K on the lift pins 34, the substrate transport robot 9 retracts the movable support base 93. Subsequently, the suction stage 3 lowers the lift pins 34 that support the glass substrate K. When the glass substrate K descends and reaches the placement surface 31, the suction stage 3 generates a vacuum pressure in the vacuum suction holes 32 and holds the glass substrate K on the placement surface 31 by vacuum suction.

[Glass substrate positioning (step S2)]
First, the first linear motor 43 drives and controls the camera gantry 6 so that the alignment camera 7 is positioned above the alignment mark M1. Subsequently, the alignment camera 7 images the alignment mark M1, and sends the obtained image data to the control device 10. The control device 10 calculates the amount of deviation of the glass substrate K from a predetermined position by performing appropriate image processing on the sent image data. The glass substrate K is positioned by driving and controlling the stage rotation driving means based on the deviation amount.

[Preparation before application (step S3)]
First, the first linear motor 43 drives and controls the application gantry 4 so that the ink discharge unit 5 comes to the upstream application start position on the glass substrate K. Subsequently, the servo motor mechanism 44 lowers the ink ejection unit 5 so that the gap between the ejection port of the inkjet nozzle 54 and the surface of the glass substrate K is a minute distance of about 0.5 mm to 1.0 mm.

Next, the operation of the apparatus including such a coating operation will be described in detail.
[Ink application (step S4)]
A series of operations for applying the target color ink to all the pixels gs on the glass substrate K of the color filter manufacturing apparatus 1 according to the present invention is performed by moving (scanning) the application gantry 4 indicated by the arrow X as shown in FIG. Thus, the ink is ejected from the inkjet head 51 onto the glass substrate K by three times of application and two lateral movements of the ink application part 5 indicated by the Y arrow at a predetermined pitch, and the application operation is completed. This will be described in more detail below.

[Application by the first forward movement]
First, the scanning process is started. Specifically, the first linear motor 43 moves the application gantry 4 forward. As a result, the ink application unit 5 moves forward in a state where the discharge port of the inkjet nozzle 54 and the surface of the glass substrate K face each other with a slight distance therebetween, as indicated by an arrow X1 in FIG. The control apparatus 10 sends a command to the ink ejection unit 5 so that the target color gs is ejected to the target color gs. As a result, the ink ejection unit 5 that is moving forward ejects a predetermined amount of ink at a predetermined timing. Then, an ink liquid of a target color is applied to each pixel gs in the black matrix BM of the glass substrate K (see steps S42 and S43 in FIG. 7). 9 and 15 show a case where the coating is performed for three pixels gs by one head module 52 for convenience. In a state where the application is started, that is, in a state where the head block 50 and the substrate K face each other, the head module 52 is disposed so as to protrude beyond the color filter formation region R by 2 pitches P in the Y direction. That is, the overall length L of the plurality of head modules 52 in this embodiment is set to be longer than the required coating width W by two pitches of the head module 52.

In this first application during forward movement, the arrangement of the pixels gs to which ink has been applied by the ejection of ink from the ink jet nozzle 54 of the ink jet head 51 according to a command from the control device 10 is as shown in FIG. The width is adjacent or overlapped by the distance in the Y direction. In other words, the pixels gs that are sequentially colored in three colors are applied in a state of being arranged in positions adjacent to each other in the Y direction (direction orthogonal to the scanning direction) and the X direction (scanning direction). In the example shown in FIGS. 9 and 15, three pixels gs of the same color are applied in the Y direction, and pixels gs of different colors are separated in the X direction and the Y direction (three pixels apart in the Y direction, and X (Position shifted by one pixel in the direction). That is, the different color pixels gs are applied so as to extend in the Y direction while being shifted by one step in the X direction, and are applied in a substantially staircase shape. Such an application state is formed over the required application width W.

Therefore, when the pixel gs around the pixel gs to which the color filter ink of the glass substrate K is applied is seen, the pixel gs of the same color is at least one side in the pixel gs adjacent to the scan direction or the direction orthogonal to the scan direction. Are filled with ink in the same manner, and with respect to the pixel gs at the edge of the applied region, the diagonally horizontal pixel gs is filled with ink of other colors.

In other words, except for the end portion of the effective pixel gs as a color filter, pixels to which ink has been applied by ejecting ink from the inkjet nozzle 54 of the inkjet head 51 by a single scan in response to a command from the control device 10 of the head block 50. With regard to gs, the ink is applied once with the distance to the other pixel gs filled with the adjacent ink being at most the distance to the diagonally horizontal pixel gs.

Thereby, the progress of drying of the ink surface in the pixel gs applied with ink becomes substantially the same in all the pixels gs applied with ink in the effective pixel gs region of the color filter forming portion of the glass substrate K.

This is due to the following reason.
As can be seen from the arrangement of the head module in FIG. 4, the color filter applied in the first scan is applied once between the RGB colors as shown in FIG. 9 or FIG. 13 depending on the direction of the pixel gs at the time of application. Since the regions are close to each other, the pixel gs in which the ink of another color (for example, green G or blue B) is applied around the pixel gs to which the ink of a certain color (for example, red R) is applied is applied. As a result, there is an application area of another color around the edge of the application area of one color at a time.

Thereby, the progress of drying of the ink of the pixel gs to which the applied ink of a certain color (for example, red R) is applied is suppressed. This is because the ink of a certain color is applied to the adjacent pixel gs of the pixel gs. This is the same as when the drying proceeds in the same atmosphere.

That is, in any one of the applied pixels gs by a single scanning process, the pixels gs of the same color or different color are always present in the same pattern, so that the ink from the surrounding pixels gs is present. The amount of evaporation is almost the same. Thereby, drying progresses uniformly in any pixel gs after application. Since the head modules 52 are arranged in the head block 50 with the length L at the equal pitch P, the application state is constant over the required application width W. Therefore, drying of all the applied pixels gs proceeds uniformly over the necessary application width W in the color filter forming region R. In addition, the pixels gs of different colors adjacent in the Y direction are shifted by one step in the X direction. However, since the size of one pixel gs is about 100 μm, the adjacent pixels gs are applied with a delay of one scan. Compared to the case, since the influence of the deviation in the X direction is small, it can be ignored and the drying can be considered to proceed uniformly. In the present invention, the direction orthogonal to the scanning direction and the position adjacent to the scanning direction is a position adjacent to the Y direction and shifted by one step in the X direction.

When the ink ejection unit 5 reaches the downstream application end position on the glass substrate K (Yes in step S44), the first linear motor 43 stops the forward movement of the application gantry 4. Thereby, the ink application part 5 stops (refer to the dashed-dotted line in FIG. 8). Then, the shift process is started. That is, the second linear motor 45 shifts the width 5 for ejecting ink by a predetermined pitch P in the Y direction as shown by an arrow Y1 in FIG. 8 (see the two-dot chain line in FIG. 8). The predetermined pitch amount may be the same as the effective application width (discharge area) of one head module 52 or a value smaller by several nozzles than that (see step S45).

[Application by first rebound]
Next, the first linear motor 43 moves the application gantry 4 backward through the scanning process again (step S41). As a result, the ink discharge section 5 moves backward as indicated by an arrow X2 in FIG. The control apparatus 10 sends a command to the ink ejection unit 5 so that the target color gs is ejected to the target color gs. As a result, the ink discharge unit 5 that is moving backward applies a predetermined amount of ink to each pixel gs in the black matrix BM of the glass substrate K by discharging a predetermined amount of ink at a predetermined timing. (See steps S42 and S43 in FIG. 7).

Also in this scanning process, as shown in FIG. 16, the pixels gs that are sequentially colored in three colors are arranged in the Y direction (direction perpendicular to the scanning direction) and the X direction (scanning direction), as in the previous scanning process. The pixels gs applied in this scanning process are shown in a dark color. Three pixels gs of the same color are applied in the Y direction, and pixels gs of different colors are applied at positions separated in the X direction and the Y direction (positions separated in the combined direction of the X direction and the Y direction). . That is, the different color pixels gs are applied so as to extend in the Y direction while being shifted by one step in the X direction, and are applied in a substantially staircase shape. Such an application state is formed over the required application width W. Therefore, any pixel gs applied in this scanning step always has the same color or different color pixels gs in the same pattern, and the amount of ink evaporated from the surrounding pixels gs. Are almost the same. Thereby, drying progresses uniformly in any pixel gs after application.

When the ink discharge unit 5 reaches the upstream application end position on the glass substrate K (Yes in step S44), the first linear motor 43 stops the application gantry 4 from traveling in the backward movement direction. Thereby, the ink application part 5 stops. The second linear motor 45 shifts the ink ejection part 5 by a predetermined pitch P in the Y direction as indicated by an arrow Y2 in FIG. 8 (shift process). This pitch amount is the same predetermined pitch P as that at the end of the forward movement. (See step S45).

[Application by the second forward movement]
Similar to the application operation by the first forward movement, the scanning process is started again, and the ink application portion 5 is applied while moving forward as indicated by an arrow X3 in FIG. The state after application is shown in FIG. As shown in FIG. 17, ink is applied to all the pixels gs in the color filter forming region R by this scanning process. In other words, since the head module 52 is provided by two pitches longer than the required coating width W, even if the ink discharge portion 5 moves two pitches in the Y direction by two shift steps, the entire color filter forming region R Ink is applied to the pixel gs without any excess or deficiency. It should be noted that the pixels other than the color filter forming region R (the left side in FIGS. 15 to 17) can be prevented from being applied by stopping the ink ejection to the head module 52.

As described above, the first forward movement (see arrow X1 in FIG. 8), the first backward movement (see arrow X2 in FIG. 8), and the second forward movement (see arrow X3 in FIG. 8) By performing the scan three times, the application process of the target color ink is completed.

In this way, all the pixels gs are filled in the color filter in which ink is applied to the entire area of the effective pixels gs by scanning the color filter formed on the glass substrate K of the head block 50 by the movement of the coating gantry several times. The cross-sectional shape of the surface of the ink after drying can be made equivalent.

That is, even if the reflection of external light is observed on the entire surface of the color filter, the shape of the applied ink surface after drying is equivalently formed, and the cross-sectional shape of the surface becomes similar. In the color filter thus produced, the entire area of the effective pixels gs is obtained. A high-quality color in which the amount of transmitted light, which is the main optical characteristic, is averaged, and the external light reflection on the surface of the color filter is made uniform over the entire surface, and there is no partial uneven distribution of light and darkness in the external light reflected light. It becomes a filter.

In addition, during each of the above-described application operations, the ink droplets applied as a test pattern are imaged while the scan camera 8 moves in the XY directions by driving the camera gantry 6 and the third linear motor in accordance with the ink application operation. Data is sent to the control device 10. The control device 10 evaluates the landing state of the ink by appropriate image processing based on the sent image data. If the defective portion is remarkable, the glass substrate K is excluded as a defective product in a subsequent process.

[Post-treatment (Step S5)]
First, the servo motor mechanism 44 raises the ink discharge portion 5 by driving the horizontal frame portion 42 upward. Thereby, the discharge port of the inkjet nozzle 54 and the surface of the glass substrate K are separated. Subsequently, the first linear motor 43 controls the application gantry 4 to move backward to retract the ink discharge unit 5 to the upstream end (origin) of the suction stage 3.

[Substrate unloading (step S6)]
The suction stage 3 breaks the vacuum pressure generated in the vacuum suction hole 32. The lift pins 34 protrude from the lift pin holes 33 and ascend to the uppermost position while supporting the glass substrate K. The substrate transfer robot 9 receives the glass substrate K on which ink has been applied by the movable support base 93 and delivers it to the next step, for example, a reduced pressure drying step.

According to the color filter manufacturing apparatus 1 of the present invention, by applying to a color filter that is an application target of ink as a coating material, averaging the amount of transmitted light that is a main optical characteristic over the entire effective area, and The surface shape of the ink after drying is flat and averaged, and the reflection of external light on the surface of the color filter is made uniform over the entire surface, so that a high-quality color filter free from partial unevenness of light and dark can be realized.

Measurement results obtained by measuring the unevenness of the surface of the pixel gs of the color filter coated with ink with a stylus type surface roughness meter using this apparatus as an indication of the stability of the cross-sectional shape of the pixel gs coated with ink as a color filter. FIG. 11A shows the measurement results when applied by another method. The graph of the measurement result of the cross section of the color filter according to the present invention, FIG. 11A, has an average shape, and is clearly different from the graph of FIG. 11B of the measurement result of the cross-sectional shape of another method.

As mentioned above, although embodiment of this invention was described, embodiment disclosed above is an illustration to the last, Comprising: The scope of the present invention is not limited to this embodiment. The scope of the present invention is defined by the terms of the claims, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

As an embodiment of the present invention, a color filter for a liquid crystal color TV having a 37-inch size will be described as an example.
When the screen size of this 37-inch video device has an aspect ratio of 16: 9, the screen is 820 mm wide and 460 mm long. In this case, the required application width “W” of the color filter is 460 mm.

The head block 50 has a red (R), green (G), and blue (B) “N” where the “N” is 3, the effective application width of the ink jet head 51 is “P”, and the length is 36 mm. Then, 15 inkjet modules are arranged for the required application width “W” of the color filter. The head block 50 is moved by a pitch of 36 mm in the Y direction before the second and subsequent coating operations following the first forward movement (movement in the X1 arrow direction) of the head block 50.

With regard to the primary colors of color filters, filters that use three colors, cyan, magenta, and yellow, in addition to the three colors of red, green, and blue are also appearing due to various demands such as recent color reproducibility. Now, a head block 50 for manufacturing a color filter with four colors in which “N” is 4 will be described as another embodiment.

FIG. 12 shows the total width of the pixel gs and the arrangement of the head blocks 50 of each color (in this example, red (R), green (G), blue (B), and yellow (Y)) in this case. As shown in FIG. 12, each color is applied to the color filter by scanning the pitch P of yellow (Y) increased by one color in addition to the application of three colors of red (R), green (G), and blue (B). The effective length gs of the color filter is increased by the operation of the coating apparatus in which the length L of the head block increases in the direction and the shift process in the direction orthogonal to the scanning direction increases once to complement the increased one color. Application to can be completed.

In this four-head configuration, as can be seen from FIG. 12, the increased yellow (Y) arrangement can be arranged in the middle of other colors, and the head module 1 can be changed without changing the size of the apparatus in the scanning direction. There is an advantage that only the width of each piece needs to be increased.

Claims

A plurality of head modules that eject ink of a single color are provided, and a head block that can apply N-color (N = 1, 2, 3,...) Ink is provided. The head block and the substrate are relative to each other in the scanning direction. A coating device for manufacturing a color filter by ejecting N color ink from the head block,
In the head block, the head modules are arranged by a length L at a predetermined pitch P in a direction orthogonal to the scan direction at predetermined intervals by sequentially changing the colors of each of the N colors.
The relationship between this length L and the required coating width W in the direction perpendicular to the scanning direction in the color filter forming region for forming the color filter is L ≧ W + (N−1) × P (N = 1, 2, 3,.・)
A coating apparatus characterized by satisfying
The plurality of head modules are arranged stepwise by arranging head modules arranged in a direction orthogonal to the scanning direction at a pitch P and arranging these head modules adjacent to each other in the scanning direction. 2. The coating apparatus according to claim 1, wherein a head module group arranged side by side is formed, and the head module group is repeatedly arranged in the direction orthogonal to the scanning direction on the head block.
The head module is provided with a plurality of ink jet nozzles for ejecting ink. In the head modules arranged in a direction perpendicular to the scanning direction, the ink ejection areas of the ink jet nozzles overlap when viewed from the scanning direction. The coating apparatus according to claim 1 or 2, wherein the coating apparatus is arranged in a state.
A plurality of head modules that eject ink of a single color are provided, and a head block that can apply N-color (N = 1, 2, 3,...) Ink is provided. The head block and the substrate are relative to each other in the scanning direction. An application method for producing a color filter by ejecting N color ink from the head block,
In the head block, the head modules are arranged by a length L at a predetermined pitch P in a direction orthogonal to the scan direction at predetermined intervals by sequentially changing the colors of each of the N colors.
The relationship between this length L and the required coating width W in the direction perpendicular to the scanning direction in the color filter forming region for forming the color filter is L ≧ W + (N−1) × P (N = 1, 2, 3,.・)
Is formed to satisfy
By ejecting ink from the head module while relatively moving the head block and the substrate in the scanning direction, pixels coated with different color inks are adjacent to each other in the direction orthogonal to the scanning direction and in the scanning direction. A coating method comprising: a scanning step of coating so that N colors are sequentially changed over a necessary coating width W at a matching position.
By sequentially repeating the scan process, the shift process for moving the head block in a direction perpendicular to the scan direction, and the scan process again, the pixel is adjacent to the pixel to which the ink of the specific color is applied in the previous scan process. 5. The pixel according to claim 4, wherein the pixel is formed by applying the same color ink in the next scanning step so that the pixel to which the same color ink is applied extends in a direction perpendicular to the scanning direction. Application method.
In a coating apparatus for manufacturing a color filter by applying a number of primary colors (N) with a plurality of inkjet heads (51),
One or more inkjet heads (51) for supplying ink of the same color constitute a head module (52), and at least both ends of the ink discharge width of the head module (52) are adjacent or overlap each other. Are arranged in the scanning direction at a pitch P, and a head block (50) in which these head modules (52) are continuously arranged in the direction orthogonal to the scanning direction by a length L is formed, and the head of the head block (50) A coating apparatus which supplies ink by changing the color sequentially for each module (52), and L is the following formula with respect to the required coating width W of the color filter.
[Formula 1]
L ≧ W + (N−1) × P (N = 1, 2, 3,...)
The coating apparatus according to claim 6, wherein the arrangement pitch P of the head modules (52) is:
[Formula 2]
P ≦ (1 / N) × W (N = 1, 2, 3,...)
In a coating apparatus for manufacturing a color filter by applying a number of primary colors (N) with a plurality of inkjet heads (51),
One or more inkjet heads (51) for supplying ink of the same color constitute a head module (52), and at least both ends of the ink discharge width of the head module (52) are adjacent or overlap each other. Are arranged in the scanning direction at a pitch P, and a head block (50) in which these head modules (52) are continuously arranged in the direction orthogonal to the scanning direction by a length L is formed, and the head of the head block (50) For each module (52), the color is sequentially changed and ink is supplied, and for the required application width W of the color filter, L is the following equation [Equation 1]
L ≧ W + (N−1) × P (N = 1, 2, 3,...)
A coating method characterized by shifting by a pitch P in a direction orthogonal to the scanning direction for each scan and scanning N times.
The coating method according to claim 8, wherein the arrangement pitch P of the head modules (52) is:
[Formula 2]
P ≦ (1 / N) × W (N = 1, 2, 3,...)