JP4710258B2 - Color filter forming method and forming apparatus - Google Patents

Description

  The present invention relates to a method of forming a color filter such as a liquid crystal color display device using an ink jet printer, and a forming apparatus therefor.

Conventionally, a color filter has three colors of red (R), green (G), and blue (B) as color filter constituent colors, and a color layer composed of these three colors and a black light-shielding pattern is made of a transparent substrate. It is comprised by providing on the board | substrate for filters (for example, glass substrate). In forming this color filter, it has been proposed to form a colored layer by a dyeing method or a pigment dispersion method using photolithography, or by a transfer method which is one of printing methods.
In addition, with the improvement in performance of ink jet printers, attempts have been made to produce color filters using the ink jet printer. Each of the nozzles is provided with a piezoelectric element (piezo element) that is deformed by applying a voltage in the ink jet print head, and the nozzle scans the pixel forming portion divided by the light shielding pattern in the width direction. However, it has been proposed to form a color filter by supplying ink to the pixel forming portion for each color filter constituent color.
JP 2001-228320 A

By the way, in general, when printing is performed by an ink jet printer using an ink jet print head having a piezoelectric element in a nozzle, ink droplets (droplets) are ejected from the nozzle. After ejecting a single amount (for example, 12 pl) of droplets, the ink is discharged in a cycle of “discharge-pause-discharge-pause-...” (The pause is to secure the time when the vibration of the ink discharge surface is settled).
However, when this ink jet printer is used for forming a color filter, the following points need to be considered. That is, in an ink jet printer, ink for an ink jet having a high solvent content is ejected, so that ink is supplied in a state where the amount of ink is increased in each pixel forming portion. In forming a color filter using an ink jet print head composed of the above, a large volume of droplets is ejected intermittently. It is necessary to make an action take place. Therefore, when the ink supply amount is controlled in this way, the scanning speed becomes slow, and there is a disadvantage that an efficient color filter cannot be formed. Further, in the case of single ejection, there is also a disadvantage that it is difficult to control the ink supply amount.
SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to enable control of an ink supply amount without affecting the scanning speed of a nozzle, and an object of the invention is to efficiently form a color filter using an ink jet printer. To do.

(Claim 1)
In consideration of the above problems, the present invention is an ink that discharges ink droplets by applying a voltage to each piezoelectric element of a nozzle on a color filter substrate in which a pixel forming portion is divided by a light shielding pattern. The jet print head is scanned relative to the pixel forming portion, and the ink of the color filter constituting color corresponding to the pixel forming portion is applied to each of the pixel forming portions of the color filter substrate. In order to form a color filter on the color filter substrate,
Each time a plurality of nozzles correspond to each of the pixel forming portions, a predetermined amount of ink is supplied to a scanning portion of the nozzle in the pixel forming portion, and a droplet having a volume set by voltage control to the piezoelectric element. A method for forming a color filter, characterized in that the number of drops or the volume of droplets from one nozzle and the droplets from another nozzle to the pixel formation portion are different from each other. Provided to solve the above problems.

(Claim 2)
In the present invention, the landing position of all the droplets ejected when the nozzle corresponds to the pixel forming portion can be set as a substantially central region in the scanning direction of the pixel forming portion.

(Claim 3)
Also, in the present invention, the light shielding pattern of the color filter substrate or the mark row provided on the surface plate on which the color filter substrate is arranged and fixed, and the marks are arranged at a fine pitch narrower than the scanning direction pitch of the light shielding pattern. It is possible to determine the discharge position and the ink supply amount based on a signal obtained by reading the mark associated with the light shielding pattern therein, and to discharge the droplets from the nozzle to the pixel forming portion. .

(Claim 4 )
According to another aspect of the present invention, an ink jet print head that discharges ink droplets by applying a voltage to the piezoelectric element of each nozzle is provided on a pixel for a color filter in which a pixel forming portion is divided by a light shielding pattern. The ink of the color filter corresponding to the pixel forming portion is supplied as a droplet from the nozzle of the ink jet print head to each of the pixel forming portions of the color filter substrate. In the apparatus for forming a color filter on the color filter substrate,
A plurality of nozzles correspond to each of the pixel forming portions, and the plurality of nozzles are supplied with a predetermined amount of ink set in advance at the nozzle scanning portion by one voltage droplet set by voltage control to the piezoelectric element. A color which is supplied by discharging a small volume of droplets, wherein the number of droplets discharged from one nozzle and the droplets from the other nozzles are different from each other in the number of pixels or the volume. This is a filter forming apparatus, and this color filter forming apparatus is provided to solve the above problems.

(Claim 5 )
In the forming apparatus of the above invention, the landing position of all droplets ejected when the nozzle corresponds to the pixel forming portion can be set as a substantially central region in the scanning direction of the pixel forming portion.

(Claim 6 )
Further, in the forming apparatus of the invention, the nozzle is provided on a light shielding pattern of the color filter substrate or a surface plate on which the color filter substrate is fixed and is finer than a pitch in the scanning direction of the light shielding pattern. A discharge position and an ink supply amount are determined based on a signal obtained by reading a mark associated with the light shielding pattern in a mark row in which marks are arranged at a pitch, and droplets are discharged to a pixel forming unit. It is possible.

(Delete)

(Delete)

( Effect of the invention of claim 1)
A nozzle that discharges ink as droplets by the operation of the piezoelectric element continuously discharges small droplets (for example, a volume of 6 droplets of one droplet). Therefore, according to the present invention, each time the nozzle corresponds to each pixel forming portion, the volume of ink set in advance to the scanning portion of the nozzle in the pixel forming portion is set by voltage control to the piezoelectric element. If the droplets are supplied by discharging a droplet, a droplet having a small droplet volume (for example, a volume of 6 pl) can be discharged to the pixel forming portion in a number of, for example, 1 to 5, and a multiple of the volume of the one droplet. The ink supply amount to the pixel forming portion can be controlled, and the scanning speed is not affected.
For example, when the voltage related to the operation of the piezoelectric element is changed by 1 V, the volume of one droplet changes by 1 pl. Therefore, by controlling the voltage, the volume of one droplet itself can be controlled, and the amount of ink supplied to the pixel forming portion becomes accurate.
In the present invention, since there are a plurality of nozzles and the number of droplets or the volume of droplets from one nozzle and the droplets from another nozzle are different from each other, the ink supply to each pixel formation unit Can be adjusted more finely.

( Effect of the invention of claim 2)
In the present invention, by setting the landing position of all droplets ejected when the nozzle corresponds to the pixel formation portion as the substantially central region in the scanning direction of the pixel formation portion, pixel formation is performed regardless of the number of ejections. The droplets land on the substantially central region of the part, and the ink is uniformly filled from the central part in the pixel forming part. On the other hand, when ejecting from the nozzles of a normal ink jet print head, the landing positions of each of the multiple droplets are fixed in the form of being aligned in the scanning direction within the pixel formation section. In addition, the ink may not be uniformly filled in the pixel forming portion. If the number of ejections is large, ink may overflow.

( Effect of the invention of claim 3)
Also, in the present invention, the light shielding pattern of the color filter substrate or the mark row provided on the surface plate on which the color filter substrate is arranged and fixed, and the marks are arranged at a fine pitch narrower than the scanning direction pitch of the light shielding pattern. If droplets are ejected from the nozzle to the pixel formation portion based on a signal obtained by reading the mark associated with the light shielding pattern in the inside, it is more effective without being affected by fluctuations in the pitch of the pixel formation portion. Ink can be reliably supplied to the pixel forming portion.

(Delete)

(Effect of the invention of claim 4 )
According to the invention of claim 4 , every time a nozzle corresponds to each pixel forming portion, a supply amount of ink set in advance in the scanning portion of the nozzle in the pixel forming portion is set by voltage control to the piezoelectric element. Since the droplets are supplied by discharging droplets of the same volume, droplets having a small volume of one droplet can be discharged to the pixel forming portion in the number of 1 to 5, for example, and the number of pixels is a multiple of the volume of the one droplet The amount of ink supplied to the forming part can be controlled, and the scanning speed is not affected.
In addition, for example, by controlling the voltage, the volume of one droplet itself can be controlled, and the amount of ink supplied to the pixel forming portion becomes accurate.
According to the forming apparatus of the present invention, there are a plurality of nozzles, and the number of discharges or the volume of droplets from one nozzle and the droplets from other nozzles to the pixel forming portion are different from each other. In addition, the ink supply to each pixel forming portion can be adjusted more finely.

(Effect of the invention of claim 5 )
According to the invention of claim 5 , by setting the landing position of all droplets discharged when the nozzle corresponds to the pixel forming portion as the substantially central region in the scanning direction of the pixel forming portion, it does not depend on the number of discharges. The droplets land on the substantially central region of the pixel forming portion, and the ink is uniformly filled from the central portion in the pixel forming portion. On the other hand, when ejecting from the nozzles of a normal ink jet print head, the landing positions of each of the multiple droplets are fixed in the form of being aligned in the scanning direction within the pixel formation section. In addition, the ink may not be uniformly filled in the pixel forming portion. If the number of ejections is large, ink may overflow.

(Effect of the invention of claim 6 )
According to a sixth aspect of the present invention, the nozzle is provided on a light shielding pattern of the color filter substrate or a surface plate on which the color filter substrate is arranged and fixed, and is finer than a pitch in the scanning direction of the light shielding pattern. A discharge position and an ink supply amount are determined based on a signal obtained by reading a mark associated with the light shielding pattern in a mark row in which marks are arranged at a pitch, and droplets are discharged to a pixel forming unit. As a result, the ink can be supplied more reliably to the pixel forming portion without being affected by the fluctuation of the pitch of the pixel forming portion.

(Delete)

Next, the present invention will be described in detail based on the embodiment shown in FIGS.
FIG. 1 schematically shows a color filter forming apparatus 1. As shown in the figure, the color filter forming apparatus 1 is transparent to a color filter substrate 2 made of a glass base material and provided with a light shielding pattern in advance. The base plate 4 can be placed and fixed on the unit 3 and moved in the scanning direction a and the sub-scanning direction b, and can be moved in the sub-scanning direction of the base plate 4 on a pedestal installed across the base plate 4. And three ink jet print heads 5 corresponding to the color filter constituent colors R, G and B.
Each of the heads 5 moves relatively in the scanning direction and the sub-scanning direction when the surface plate 4 moves in the scanning direction a and the sub-scanning direction b, and each head 5 is placed and fixed on the surface plate 4. The surface of the color filter substrate 2 on which the light shielding pattern is provided is scanned, and at the time of scanning, the color filter constituent color ink set in the pixel forming portion is applied to the pixel forming portion divided by the light shielding pattern. If the head 5 corresponds, ink is ejected from the head 5 as droplets, and ink is supplied to each pixel forming portion by landing the droplet on the pixel forming portion and filling the ink.

In each of the ink jet print heads 5, nozzles 6 that discharge ink as droplets are arranged by the operation of the piezoelectric elements, and a plurality of red nozzles 6 are arranged in the pixel forming portion 7 that forms, for example, a red color filter constituent color during scanning. Correspondingly, ink is supplied from each nozzle 6. In the following, for ease of explanation, ink supply is exemplified by a red nozzle, but the same applies to the other two colors of ink supply.
In the present invention, by using this ink jet print head, the coating thickness when dried after ink supply is set to the same color filter configuration according to the pitch of the stripe-shaped pixel forming portion 7 for each color filter configuration color. The color pixel forming portions are designed to be the same. That is, droplets are discharged by the nozzle 6 and the volume of one droplet is reduced.
For example, the volume of one droplet in the nozzle 6 is 6 pl, and this is discharged at a discharge number of 1 to 5. As a result, the discharge amount per nozzle can be controlled by an amount which is n times 6 pl, and discharge is performed at the time of one scanning of one pixel formation unit, so that the pitch of the pixel formation unit is temporarily widened or narrowed. Even in such a case, by adjusting the volume of one droplet, the condition for making the coating thickness constant can be satisfied, and there is no need to slow down the scanning speed.
Further, in a nozzle that discharges droplets using the operation of the piezoelectric element, for example, when the voltage is changed by 1 V, the discharge amount changes by 1 pl. It becomes possible to control, and the discharge amount from the nozzle can be finely adjusted according to the pitch of the pixel forming portion.

The nozzle 6 continuously discharges a plurality of droplets. As shown in FIG. 2, when each nozzle 9 corresponds to the pixel forming unit 7 during scanning, the landing positions of all the droplets 8 to be discharged Is the center of the pixel forming portion 7 in the scanning direction (see FIG. 3). As a result, the ink is filled from the central portion in the pixel forming portion 7, and a high ink supply can be realized.
The discharge of the droplet 8 is performed by controlling the piezoelectric element in the nozzle 6, and in particular, in the case of a plurality of discharges, the droplet 8 of the intermediate discharge is the center line position c in the scanning direction in the pixel forming unit 7. It is set to be. For example, as shown in FIG. 3, when seven droplets having a volume of 6 pl of one droplet are shot, the fourth droplet 8 is controlled to land at the center line position c.

Although ink supply described above is a case of forming a color filter pixel formation portion is in the striped shape, forming method of the color filter of the present invention is not limited thereto, the pixel formation portion blackout The present invention can also be implemented in the case of a cell shape surrounded by a pattern.
As shown in FIG. 4, the pixel forming portion 7 has a cell shape, and when the head scans and moves, the scanning position of the nozzle 6 may overlap the position of the line segment 10 along the scanning direction of the light shielding pattern 9. In this case, in the present invention, ink is supplied as follows.
First, it is set in advance that the ink supply amount of each cell-like pixel forming unit 7 corresponding to the same color filter constituent color is made constant. Then, in order to eject ink with the constant ink supply amount to each of the pixel forming portions 7 as a droplet at the time of one scanning, the droplet discharge number is preset as an ink supply amount (constant). Calculation is based on the volume of one droplet. This is the calculated droplet discharge number.
Further, the light shielding pattern position that is known in advance is associated with the nozzle scanning position, and the nozzle at which the nozzle scanning position overlaps the position of the line segment 10 of the light shielding pattern during scanning is grasped in advance. Then, ejection / non-ejection of the nozzle is preset so that the ejection operation is not performed when the nozzle overlaps the line segment 10 during scanning.
Various information such as the calculated number of droplet discharges, the shape of the light-shielding pattern, the nozzle scanning position, and the pre-setting of nozzle discharge / non-discharge are handled as data input to the control device of the color filter forming apparatus 1. It is. Then, the droplets of the calculated droplet discharge number are discharged from the nozzles 6 corresponding to the pixel forming unit 7 at the time of one scan based on the preset discharge / non-discharge of the nozzles. For example, if 15 shots (number of ejections) per pixel forming portion, 3 nozzles are equally set to 5 shots × 3. When one nozzle is positioned at the line segment 10 of the light shielding pattern 9, the other two nozzles are provided so as to have 7 shots and 8 shots. Note that the volume of one droplet is set in advance by the method described above.
In this way, even when the scanning position of the nozzle overlaps the line segment in the scanning direction of the light shielding pattern, the required number of droplets is discharged from the other nozzles, so that the head itself is used in the conventional method. There is no need to adjust the inclination of the.
Even in the case of a striped light shielding pattern, if a nozzle that cannot be ejected is generated, it can be compensated by increasing the number and volume of droplets from neighboring nozzles.

  In the above example, the pixel forming unit 7 has a cell shape, and is a countermeasure when the line segment 10 at the position along the scanning direction of the light shielding pattern 9 overlaps the nozzle scanning position. This countermeasure can be applied as follows when the shape is a stripe or stripe. In other words, if there is a defective nozzle in the head and there is a difference in the ink supply amount in the pixel formation section, the shape of the light-shielding pattern and the nozzle scanning position including the defective nozzle are matched in the same way as described above. In addition, it is possible to select other nozzles in each pixel forming portion corresponding to the scanning position of the defective nozzle and discharge droplets corresponding to the ink supply amount set in advance from these nozzles.

The discharge positions of the nozzles of the ink jet print heads 5 in the color filter forming apparatus 1 described above are adjusted using the mark rows 11 provided on the surface plate 4 on which the color filter substrate 2 is arranged. The mark row 11 is located on the side surface of the surface plate 4 along the scanning direction, and the marks are arranged at a fine pitch narrower than the pitch of the light shielding pattern 9 in the scanning direction. Each position in the scanning direction of the light shielding pattern is associated. An encoder signal can be extracted from the mark row 11 by a reading device (not shown).
Based on the information obtained by reading the mark row 11 during scanning when ink is supplied, droplet discharge is performed from the head 6 to the corresponding pixel forming portion 7. In this way, position information is obtained as a pulse signal from the mark row 11 provided on the surface plate 4, and the droplets are discharged by performing synchronous control based on the pulse signal. Thus, droplet discharge can be appropriately performed on the pixel forming portion 7 without being affected.

Further, it is assumed that the mark cycle of the mark row 11 does not match the cycle of the pixel formation portion pitch (position pitch of the light shielding pattern in the scanning direction). In such a case, a frequency for controlling the piezoelectric element is obtained after frequency conversion of the pulse signal obtained by reading the mark row 11 is performed.
Further, there may be a case where the pitch of the pixel forming portion varies due to the aberration of the exposure machine. In such a case, the position information is directly read from the light shielding pattern, or the signal for reading the mark row 11 is addressed, the address of the ejection position of each light shielding pattern is stored, and the stored address is stored. Discharge synchronization and discharge control are performed every time. At this time, it is necessary to increase the ink supply amount when the pitch of the pixel forming portions 7 is wide, and to decrease the ink supply amount when the pixel forming portion 7 is narrow. And voltage adjustment.

  Further, the color filter forming apparatus 1 includes a technique for facilitating alignment of the discharge start position and the like. In order to implement this, an inverted microscope 12 is provided below the transparent portion 3 of the surface plate 4 in the color filter forming apparatus 1, and the position of the light-shielding pattern and the head of the color filter substrate 2 to which ink is supplied. Match the position of the nozzle in. Since the positional relationship between the two is directly adjusted in this way, the error is small.

When droplets are discharged from the nozzle 6, the time from when each nozzle receives a discharge signal (waveform) until it pops out of the nozzle plate (tip surface with nozzle holes) and the discharge speed after the discharge are determined by the channel ( Differences occur due to mechanical accuracy and electrical delay of the liquid chamber, and the landing position is slightly shifted. Therefore, it is preferable to change the synchronization frequency for each nozzle in consideration of the amount of deviation, and this improves the accuracy of the landing position.
In addition, there is a share wave method for three-phase divided discharge in the nozzle discharge method, but even in this case, the landing position for each phase is slightly shifted due to the above reason. For this reason, even in a nozzle using this method, changing the frequency for each phase is effective in improving the accuracy of the landing position.

  Further, the method for forming a color filter of the present invention can be applied to a method for forming a functional liquid film (for example, EL). In the case of an EL display device, an EL material may be discharged onto an EL substrate by an ink jet print head. In this case, a light shielding pattern is provided on the EL substrate as necessary.

It is explanatory drawing which shows schematically the color filter formation apparatus which enforces an example of the formation method of the color filter which concerns on this invention. It is explanatory drawing which shows the pixel formation part in an inkjet print head and the board | substrate for color filters. It is explanatory drawing which shows the state which made the droplet land in the center of a pixel formation part. It is explanatory drawing which shows the pixel formation part which is a cell form, and a nozzle scanning position.

DESCRIPTION OF SYMBOLS 1 ... Color filter formation apparatus 2 ... Color filter substrate 4 ... Surface plate 5 ... Inkjet print head 6 ... Nozzle 7 ... Pixel formation part 8 ... Droplet 9 ... Light-shielding pattern 10 ... Line segment 11 ... Mark row 12 ... Inverted microscope

Claims (6)

An ink jet print head that discharges ink droplets by applying a voltage to the piezoelectric element of each nozzle relative to the pixel forming portion relative to the color filter substrate in which the pixel forming portion is divided by a light shielding pattern. The color filter substrate is scanned and supplied to each of the pixel forming portions of the color filter substrate as ink droplets of the color filter constituting color corresponding to the pixel forming portion from the nozzle of the ink jet print head. In forming a color filter on
Each time a plurality of nozzles correspond to each of the pixel forming portions, a predetermined amount of ink is supplied to a scanning portion of the nozzle in the pixel forming portion, and a droplet having a volume set by voltage control to the piezoelectric element. A method for forming a color filter, characterized in that the number or volume of droplets discharged from one nozzle and the droplets from another nozzle to the pixel formation portion are different from each other.   The method for forming a color filter according to claim 1, wherein landing positions of all droplets ejected when the nozzle corresponds to the pixel forming portion are set to a substantially central region in the scanning direction of the pixel forming portion.   The light-shielding pattern of the color filter substrate or the light-shielding pattern in a mark row provided on a surface plate on which the color filter substrate is arranged and fixed and arranged with a fine pitch narrower than the pitch in the scanning direction of the light-shielding pattern. The method for forming a color filter according to claim 1 or 2, wherein a discharge position and an ink supply amount are determined based on a signal obtained by reading a corresponding mark, and droplets are discharged from the nozzle to the pixel forming portion. An ink jet print head that discharges ink droplets by applying a voltage to the piezoelectric element of each nozzle relative to the pixel forming portion relative to the color filter substrate in which the pixel forming portion is divided by a light shielding pattern. The color filter substrate is scanned and supplied to each of the pixel forming portions of the color filter substrate as ink droplets of the color filter constituting color corresponding to the pixel forming portion from the nozzle of the ink jet print head. In an apparatus for forming a color filter in
A plurality of nozzles correspond to each of the pixel forming portions, and the plurality of nozzles are supplied with a predetermined amount of ink set in advance at the nozzle scanning portion by one voltage droplet set by voltage control to the piezoelectric element. A color which is supplied by discharging a small volume of droplets, wherein the number of droplets discharged from one nozzle and the droplets from the other nozzles are different from each other in the number of pixels or the volume. Filter forming device. The landing positions of all droplets ejected when the nozzle corresponding to the pixel formation portion, forming device of a color filter according to claim 4 in which the substantially central region of the scanning direction of the pixel formation portions. The nozzle is provided in a light shielding pattern of the color filter substrate or in a mark row in which marks are arranged at a fine pitch narrower than the pitch in the scanning direction of the light shielding pattern. The color according to claim 4 or 5 , wherein a discharge position and an ink supply amount are determined based on a signal obtained by reading a mark associated with the light shielding pattern, and droplets are discharged to a pixel forming portion. Filter forming device.

Images