JP4586373B2 - Droplet ejection method - Google Patents

Description

  The present invention relates to a droplet discharge method.

2. Description of the Related Art Conventionally, a method of applying a material to a region partitioned for each pixel using an ink jet device (droplet discharge device) is known. For example, Patent Document 1 discloses a method for forming filter elements of a color filter substrate using an ink jet device or light emitting portions arranged in a matrix in a matrix display device.
JP 2003-127343 A

  In the above-mentioned Patent Document 1, a method of applying a coloring material, for example, to a region (discharged portion) partitioned for each pixel is disclosed, but the head of an ink jet apparatus is particularly driven for conditions for increasing the discharge efficiency. The conditions for reducing power consumption are not described. An object of the present invention is to provide a droplet discharge apparatus and a droplet discharge method that can reduce power consumption during droplet discharge.

  In order to solve the above problems, a droplet discharge device of the present invention is a droplet discharge device for drawing a drawing pattern of a predetermined pitch, and includes a plurality of heads arranged in parallel, and discharge is performed for each head. It is possible to have a configuration in which the ejection timing between the heads is different. According to such a droplet discharge device, since the discharge timing between the heads is different, it is possible to reduce power consumption for driving the head. In other words, if the ejection is performed between the heads simultaneously, the individual heads must be driven at the same time, resulting in an increase in power consumption. However, by changing the ejection timing between the heads as in the present invention, the head drive It was possible to reduce the power consumption.

  The pitch between the columns of the heads may be configured to be a non-integer multiple of the pitch of the drawing pattern. In this case, since the pitch between the rows of the heads is not an integral multiple of the pitch of the drawing pattern, it is preferable to discharge the heads at different timings while scanning the heads according to the pitch of the drawing patterns. It is also possible to contribute to the reduction of power consumption.

  Further, in the present invention, the drawing pattern is a coloring pattern of three colors constituting a color filter, and the pitch between the columns of the heads is configured to be a non-integer multiple of the pitch between common colors in the coloring pattern. Can be. In this case, since the pitch between the rows of the heads is not an integral multiple of the pitch between the common colors, it is preferable to discharge the heads at different timings while scanning the heads according to the pitch between the common colors. Thus, it is possible to contribute to reduction of power consumption for driving the head.

  Furthermore, in the present invention, the head may include at least one nozzle row arranged in a row, and the head may be configured to scan along a direction substantially perpendicular to the nozzle row. In this case, simultaneous ejection can be performed in the row direction of the nozzles, and such a pattern extending in the longitudinal direction can be drawn more efficiently.

  Next, in order to solve the above problems, a droplet discharge method of the present invention is a droplet discharge method for drawing a drawing pattern of a predetermined pitch, and is a droplet discharge method including heads arranged in a plurality of rows. The apparatus is characterized in that the ejection is performed for each head and the ejection timing is different for each adjacent head. According to such a droplet discharge method, since the discharge timing between the heads is made different, it is possible to reduce power consumption for driving the head.

  The ejection can be performed by setting the pitch between the rows of the heads to a non-integer multiple of the pitch of the drawing pattern. In this case, since the pitch between the rows of the heads is not an integral multiple of the pitch of the drawing pattern, it is preferable to discharge the heads at different timings while scanning the heads according to the pitch of the drawing patterns. By adopting such a method, it is possible to reduce power consumption for driving the head.

  Further, in the present invention, the three-color coloring pattern constituting the color filter is used as the drawing pattern, and ejection is performed with the inter-column pitch of the heads being a non-integer multiple of the common color pitch in the coloring pattern. Can do. In this case, since the pitch between the rows of the heads is not an integral multiple of the pitch between the common colors, the heads are scanned in accordance with the pitch between the common colors, and the ejection is performed at different timings between the heads. It is preferable, and the power consumption for driving the head can be reduced by adopting such a method.

  Furthermore, in the present invention, a head having at least one nozzle row arranged as the head can be used, and ejection can be performed by scanning the head along a direction substantially perpendicular to the nozzle row. In this case, simultaneous ejection can be performed in the row direction of the nozzles, and such a pattern extending in the longitudinal direction can be drawn more efficiently.

(A. Overall configuration of droplet discharge device)
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
As shown in FIG. 1, an ink jet device (droplet discharge device) 100 includes a tank 101 that stores ink (liquid material) 111, a tube 110, and a discharge scanning unit 102 connected to the tank 101 via the tube 110. And.

  The ejection scanning unit 102 can support a carriage 103 including a plurality of heads 114 (see FIG. 2), a first position control device 104 that controls the position of the carriage 103, and a base 10A that is an object to which ink is applied. A stage 106, a second position control device 108 that controls the position of the stage 106, and a control unit 112 are provided. A plurality of heads 114 (see FIG. 2) provided in the carriage 103 and the tank 101 are connected by a tube 110, and the ink 111 is supplied from the tank 101 to each head 114 (see FIG. 2) by compressed air.

  The first position control device 104 moves the carriage 103 along the X-axis direction and the Z-axis direction orthogonal to the X-axis direction in response to a signal from the control unit 112. Further, the first position control device 104 also has a function of rotating the carriage 103 around the Z axis. In the present embodiment, the Z-axis direction is a direction parallel to the vertical direction (that is, the direction of gravitational acceleration).

  The second value control device 108 moves the stage 106 along the Y-axis direction orthogonal to both the X-axis direction and the Z-axis direction in response to a signal from the control unit 112. Further, the second position control device 108 also has a function of rotating the stage 106 around the Z axis. In the present specification, the first position control device 104 and the second position control device 108 may be referred to as “scanning unit”.

  The stage 106 has a plane parallel to both the X-axis direction and the Y-axis direction. Further, the stage 106 is configured to fix or hold the base body 10A having an ejected portion to which ink is applied on the plane.

  In this specification, the X-axis direction, the Y-axis direction, and the Z-axis direction coincide with the direction in which one of the carriage 103 and the stage 106 moves relative to the other. The virtual origin of the XYZ coordinate system that defines the X-axis direction, the Y-axis direction, and the Z-axis direction is fixed to the reference portion of the inkjet apparatus 100. In this specification, the X coordinate, the Y coordinate, and the Z coordinate are coordinates in such an XYZ coordinate system. Note that the above virtual origin may be fixed not only to the reference portion but also to the stage 106 or to the carriage 103.

  In the present embodiment, the carriage 103 is configured to be movable in the Y-axis direction by the first position control device 104, and the stage 106 is configured to be movable in the X-axis direction by the second position control device 108. That is, the first position controller 104 and the second position controller 108 change the relative position of the head 114 with respect to the stage 106. More specifically, by these operations, the carriage 103 moves relatively in the Y axis direction while maintaining a predetermined distance in the Z axis direction with respect to the discharge target portion positioned on the stage 106, that is, Scan relatively. Note that “relative movement” or “relative scanning” includes moving at least one of the side from which the ink 111 is ejected and the side from which the ejected material is landed (the side to be ejected) with respect to the other. Meaning.

  Furthermore, the relative movement of the carriage 103 means that the relative position of the carriage 103 with respect to the stage 106 changes. For this reason, in this specification, it is described that the carriage 103 moves relative to the stage 16 even when the carriage 103 is stationary with respect to the ink jet apparatus 100 and only the stage 106 moves. In addition, a combination of relative scanning or relative movement and material discharge may be referred to as “application scanning”. The carriage 103 and the stage 106 further have a degree of freedom of translation and rotation other than those described above. However, in the present embodiment, descriptions relating to degrees of freedom other than the above degrees of freedom are omitted for the purpose of simplifying the explanation.

  On the other hand, the control unit 112 is configured to receive ejection data representing a relative position at which the ink 111 should be ejected from, for example, an external information processing apparatus.

(B. Carriage)
FIG. 2 is a view of the carriage 103 observed from the stage 106 side, and the direction perpendicular to the paper surface of FIG. 2 is the Z-axis direction. In FIG. 2, the illustrated horizontal direction is the X-axis direction, and the illustrated vertical direction is the Y-axis direction.

  As shown in FIG. 2, the carriage 103 holds a plurality of heads 114 each having substantially the same structure. In the present embodiment, the number of heads 114 held by the carriage 103 is 24. Each head 114 has a plurality of nozzles 118 (see FIG. 3) on the bottom surface as ejection openings for the ink 111. The bottom shape of each head 114 is a polygon having two long sides and two short sides. As shown in FIG. 2, the bottom surface of the head 114 faces the stage 106, and the long side direction and the short side direction of the head 114 are parallel to the X-axis direction and the Y-axis direction, respectively.

(C. Head)
FIG. 3 shows the bottom structure of the head 114. The head 114 has a plurality of nozzles 118 arranged in the X-axis direction. The plurality of nozzles 118 form a row while maintaining a predetermined pitch in the X-axis direction, and one nozzle row is formed for each head 114 in the present embodiment. The head 114 is configured to be able to scan along a direction (Y-axis direction) perpendicular to the direction in which the nozzles 118 are arranged. Note that the number of nozzle rows included in one head 114 is not limited to one, and may be a plurality of rows.

  In the present embodiment, a nozzle row is constituted by 90 nozzles 118, that is, one head 114 has 90 nozzles. However, 5 nozzles at both ends of the nozzle row are set as “pause nozzles”, and the ink 111 is not ejected from these 10 “pause nozzles”. For this reason, of the 90 nozzles 118 in the head 114, 80 nozzles 118 may be referred to as “ejection nozzles”.

  Further, the number of nozzles 118 in one head 114 is not limited to 90. One head 114 may be provided with 180 nozzles or 360 nozzles. In the present invention, the number of discharge nozzles is not limited to 80. One head 114 may have P ejection nozzles. Here, P is a natural number equal to or greater than 2, and may be equal to or less than the total number of nozzles in the head 114.

  On the other hand, FIG. 4 is a perspective view (a) and a cross-sectional view (b) showing the configuration of the ejection portion of the head 114. As shown in FIGS. 4A and 4B, the head 114 includes a diaphragm 126 and a nozzle plate 128. Between the vibration plate 126 and the nozzle plate 126, a liquid reservoir 129 that is always filled with the ink 111 supplied from the tank 101 (see FIG. 1) through the hole 131 is disposed.

  A plurality of partition walls 122 are arranged between the diaphragm 126 and the nozzle plate 128. A portion surrounded by the diaphragm 126, the nozzle plate 128, and the pair of partition walls 122 is a cavity 120. Since the cavities 120 are provided corresponding to the nozzles 118, the number of the cavities 120 and the number of the nozzles 118 are the same. The ink 111 is supplied from the liquid reservoir 129 to the cavity 120 via the supply port 130 positioned between the pair of partition walls 122.

  On the diaphragm 126, vibrators 124 are arranged corresponding to the respective cavities 120. The vibrator 124 includes a piezo element 124C and a pair of electrodes 124A and 124B sandwiching the piezo element 124C. By applying a driving voltage between the pair of electrodes 124A and 124B, the ink 111 is ejected from the corresponding nozzle 118. The shape of the nozzle 118 is adjusted so that a liquid material is discharged from the nozzle 118 in the Z-axis direction.

  Here, the control unit 112 (FIG. 1) may be configured so as to give a signal to each of the plurality of vibrators 124 independently of each other. That is, the volume of the ink 111 ejected from the nozzle 118 may be controlled for each nozzle 118 according to a signal from the control unit 112. In such a case, the volume of the ink 111 ejected from each of the nozzles 118 is variable between 0 pl to 42 pl (picoliter). The control unit 112 can also set the nozzle 118 that performs the ejection operation during the application scan and the nozzle 118 that does not perform the ejection operation.

  In this specification, a portion including one nozzle 118, a cavity 120 corresponding to the nozzle 118, and a vibrator 124 corresponding to the cavity 120 may be referred to as “ejection unit 127”. According to this notation, one head 114 has the same number of ejection units 127 as the number of nozzles 118. The discharge unit 127 may include an electrothermal conversion element instead of the piezo element. That is, the discharge unit 127 may have a configuration for discharging a material by utilizing thermal expansion of the material by the electrothermal conversion element.

(D. Control unit)
Next, the configuration of the control unit 112 will be described. As shown in FIG. 5, the control unit 112 includes an input buffer memory 200, a storage unit 202, a processing unit 204, a scan driving unit 206, and a head driving unit 208. The buffer memory 202 and the processing unit 204 are connected so that they can communicate with each other. Further, the processing unit 204 and the storage unit 202 are connected to be able to communicate with each other, the processing unit 204 and the scan driving unit 206 are connected to be able to communicate with each other, and further, the processing unit 204 and the head driving unit 208 are connected to each other. Are connected so that they can communicate with each other. The scanning drive unit 206 is connected to the first position control unit 104 and the second position control unit 108 so as to be able to communicate with each other. Similarly, the head driving unit 208 is connected to each of the plurality of heads 114 so as to communicate with each other.

  The input buffer memory 200 receives ejection data for ejecting droplets made of ink 111 from an external information processing apparatus. The ejection data includes data representing the relative positions of all the ejected portions on the substrate 10A and data indicating the number of relative scans required to apply the ink 111 to all the ejected portions to a desired thickness. And data specifying the nozzle 118 functioning as an on-nozzle and data specifying the nozzle 118 functioning as an off-nozzle. The input buffer memory 200 supplies the ejection data to the processing unit 204, and the processing unit 204 stores the ejection data in the storage unit 202. In FIG. 5, the storage means 202 is a RAM.

  The processing unit 204 gives data indicating the relative position of the nozzle 118 to the discharge target unit to the scan driving unit 206 based on the discharge data in the storage unit 202. The scanning drive unit 206 gives a drive signal corresponding to this data and the ejection cycle EP (see FIG. 7) to the first position control unit 104 and the second position control unit 108. As a result, the head 114 performs relative scanning with respect to the discharge target portion. On the other hand, the processing unit 204 gives a selection signal SC for designating ON / OFF of the nozzle 118 at each ejection timing to the head driving unit 208 based on the ejection data stored in the storage unit 202 and the ejection cycle EP. The head driving unit 208 gives the ejection signal ES necessary for ejecting the ink 111 to the head 114 based on the selection signal SC. As a result, the ink 111 is ejected as droplets from the corresponding nozzle 118 in the head 114.

  The control unit 112 may be a computer including a CPU, a ROM, and a RAM. In this case, the function of the control unit 112 is realized by a software program executed by a computer. Of course, the control unit 112 may be realized by a dedicated circuit (hardware).

Next, the configuration and function of the head driving unit 208 in the control unit 112 will be described.
As shown in FIG. 6, the head drive unit 208 includes one drive signal generation unit 203 and a plurality of analog switches AS. Further, as shown in FIG. 7, the drive signal generation unit 203 generates a drive signal DS. The potential of the drive signal DS changes with respect to the reference potential L over time. Specifically, the drive signal DS includes a plurality of ejection waveforms P that are repeated at the ejection cycle EP. Here, the discharge waveform P corresponds to a drive voltage waveform to be applied between the pair of electrodes of the vibrator 124 in order to discharge one droplet from the nozzle 118.

  The drive signal DS is supplied to each input terminal of the analog switch AS. Each of the analog switches AS is provided corresponding to each of the ejection units 127. That is, the number of analog switches AS and the number of ejection units 127 (that is, the number of nozzles 118) are the same.

  The processing unit 204 supplies a selection signal SC (SC1, SC2,...) Indicating ON / OFF of the nozzle 118 to each analog switch AS. Here, the selection signal SC can take either a high level or a low level independently for each analog switch AS. On the other hand, the analog switch AS supplies the ejection signal ES (ES1, ES2,...) To the electrode 124A of the vibrator 124 in accordance with the drive signal DS and the selection signal SC. Specifically, when the selection signal SC is at a high level, the analog switch AS propagates the drive signal DS as the ejection signal ES to the electrode 124A. On the other hand, when the selection signal SC is at a low level, the potential of the ejection signal ES output from the analog switch AS becomes the reference potential L. When the drive signal DS is applied to the electrode 124A of the vibrator 124, the ink 111 is ejected from the nozzle 118 corresponding to the vibrator 124. A reference potential L is applied to the electrode 124B of each vibrator 124.

  In the example shown in FIG. 7, the high-level period in each of the two selection signals SC <b> 1 and SC <b> 2 so that the discharge waveform P appears in each of the two discharge signals ES <b> 1 and ES <b> 2 with a period 2EP that is twice the discharge period EP. And a low level period are set. As a result, the ink 111 is ejected from each of the two corresponding nozzles 118 at a cycle of 2EP. Further, a common drive signal DS from the common drive signal generation unit 203 is given to each of the vibrators 124 corresponding to these two nozzles 118. For this reason, the ink 111 is ejected from the two nozzles 118 at substantially the same timing.

  With the above configuration, the inkjet apparatus 100 performs application scanning of the ink 111 according to the ejection data given to the control unit 112.

  Next, the ejection timing of the ink 111 will be described with reference to FIG. FIG. 8A to FIG. 8C are explanatory diagrams showing the discharge timing of the heads (HEAD1, HEAD2, HEAD3) arranged in parallel in three rows, and the drawing directions shown in the drawings are the heads (HEAD1 to 3). The direction of scanning simultaneously, that is, the direction of scanning of the carriage 103 (see FIG. 2) is shown.

  In the present embodiment, the base 10A to be coated on which the drawing is performed by the ink jet apparatus 100 is a color filter substrate for forming a color filter, and an area partitioned for each pixel is used as an ejection target 301. A plurality of inks 111 are provided, and ink 111 is selectively applied to the ejected portion 301 to perform drawing. On the color filter substrate 10A, there are R, G, B discharge target portions 301 for different colors of R (red), G (green), and B (blue) along the scanning direction of the heads (HEAD1 to HEAD3). , R, G, B... Here, the discharged portion 301 is configured by a pattern having a predetermined pitch P1 between the same colors.

  On the other hand, in the ink jet apparatus 100, each head (HEAD1 to 3) can be ejected, and the ejection timing of each head (HEAD1 to 3) is different. That is, as shown in FIG. 8A, HEAD1 is positioned on the R (red) ejection target 301, and at the timing when the ink 111 is ejected to the R (red) ejection part 301, HEAD2 And HEAD3 are located on the G (green) and B (blue) discharged portions 301, respectively, and are not discharged. Further, as shown in FIG. 8B, HEAD3 is positioned on the R (red) ejected portion 301, and at the timing when the ink 111 is ejected to the R (red) ejected portion 301, HEAD1 And HEAD2 are located on the G (green) and B (blue) discharged portions 301, respectively, and are not discharged. Further, as shown in FIG. 8C, HEAD2 is positioned on the R (red) ejection target 301, and at the timing when the ink 111 is ejected to the R (red) ejection part 301, HEAD3 And HEAD1 are positioned on the G (green) and B (blue) discharged portions 301, respectively, and are not discharged.

  In the present embodiment, the pitch between the rows of heads (for example, the distance between HEAD1 and HEAD2) is a non-integer multiple (here, about 1.3 times) of the pitch P1 between the same colors on the substrate 10A described above. It is configured as follows. The HEADs 1 to 3 configured with such an inter-column pitch are scanned in the direction in which the pattern of the base body 10A is arranged, and are positioned on a common pattern element, here, on the R (red) discharge target 301. Discharge is selectively performed from HEAD.

  The discharge timing as described above is shown in FIG. FIG. 9B shows the timing at which each of the HEADs 1 to 3 ejects the substrate 10A having the pattern as shown in FIG. In the present embodiment, when HEAD is positioned at the R (red) ejection target 301 shown in FIG. 9A, an ON signal is generated, and ejection is performed in the order of HEAD1 → HEAD3 → HEAD2. .

  According to the ink jet apparatus 100 of this embodiment, since the ejection timing between the heads (HEAD 1 to 3) is different, it is possible to reduce power consumption for driving the head. That is, if ejection is simultaneously performed between the heads (HEAD 1 to 3), the power consumption of the head drive increases, but the head drive can be performed by changing the ejection timing between the heads (HEAD 1 to 3) as in the present invention. It is possible to reduce power consumption.

  Hereinafter, an example in which the above-described inkjet device 100 is applied to manufacture of a color filter substrate will be described. A base body 10A shown in FIG. 10 is a base material for manufacturing a color filter substrate, and has a plurality of discharged portions 18R, 18G, and 18B arranged in a matrix. The planar arrangement of the discharged portions 18R, 18G, and 18B is a stripe arrangement like the color filter substrate 10A shown in FIG.

  The base 10 </ b> A includes a support substrate 12 having optical transparency, a black matrix 14 formed on the support substrate 12, and a bank 16 formed on the black matrix 14. The black matrix 14 is made of a light-shielding material. The black matrix 14 and the bank 16 on the black matrix 14 are arranged on the support substrate 12 so as to define a plurality of matrix-like light transmission portions, that is, a plurality of matrix-like pixel regions.

  In each pixel region, the recesses defined by the support substrate 12, the black matrix 14, and the bank 16 correspond to the discharged portions 18R, 18G, and 18B. The discharged portion 18R is a region where a filter layer that transmits only light in the red wavelength region is formed, and the discharged portion 18G is a region where a filter layer that transmits only light in the green wavelength region is formed. Yes, the discharged portion 18B is a region where a filter layer that transmits only light in the blue wavelength region is formed.

  Ink (here, each coloring material) is applied to each of the discharged portions 18R, 18G, and 18B using the above-described inkjet device 100. In this case, as described above, the ejection timing between the heads arranged in parallel is made different to reduce the power consumption for driving the head.

  In addition, as another example of the target portion to be ejected shown in the present embodiment, a region for forming a wiring (for example, a metal wiring) having a pattern with a predetermined pitch can be exemplified. That is, the ink jet apparatus 100 of the present embodiment can also be applied to a wiring manufacturing apparatus that manufactures metal wiring by discharging a liquid wiring material. Further, for example, when manufacturing a matrix type display device, the present embodiment is also applied to the case where a component (for example, a light emitting layer forming material) of each pixel is selectively applied to a region partitioned for each pixel. Inkjet apparatus 100 can also be applied.

  Further, in the above-described embodiment, an example in which a color filter having a stripe arrangement is manufactured has been described. However, for example, the inkjet device 100 of the present embodiment can be applied to a color filter having a delta arrangement or a mosaic arrangement.

1 is a conceptual diagram illustrating a configuration of an inkjet device as an example of a droplet discharge device of the present invention. FIG. 2 is a bottom view illustrating a configuration of a carriage provided in the ink jet apparatus of FIG. 1. FIG. 3 is an explanatory diagram illustrating a configuration of a head provided in a carriage and a configuration of a discharge target portion. FIG. 4 is a perspective view and a cross-sectional view illustrating a configuration of a discharge unit provided in the head. The block diagram which shows the structure of the control part with which the inkjet apparatus of FIG. 1 was equipped. The block diagram which shows the structure of a head drive part. 6 is a timing chart showing a drive signal, a selection signal, and an ejection signal in the head drive unit. Explanatory drawing which shows the discharge timing of each head with respect to a base | substrate. Explanatory drawing which shows the discharge timing of each head with respect to a base | substrate with a drive waveform. Sectional drawing which shows the structure of the base | substrate for manufacturing a color filter substrate.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 100 ... Inkjet apparatus (droplet discharge apparatus), 103 ... Carriage, 106 ... Stage, 114 ... Head, 118 ... Nozzle (discharge nozzle), 301 ... To-be-discharged part

Claims (4)

Prescribed portions of the first color, the discharged area between the second prescribed portions of the color and the third of the discharge portion the prescribed portions of the same color in one direction of the colors are periodically arranged in a first pitch A droplet discharge method for discharging droplets to
Each of the plurality of nozzles has a plurality of nozzles, and simultaneously faces the different color discharged portions of the first color discharged portion, the second color discharged portion, and the third color discharged portion. As described above, the first color, the second color, and the second color are arranged in the one direction with respect to the first head, the second head, and the third head arranged at a second pitch that is a non-integer multiple of the first pitch. And supplying the droplet of one color of the third color and the third color,
The first head, the second head, and the third head, the first color discharged portion, the second color discharged portion, and the third color discharged portion; Facing each other,
Of the first head, the second head, and the third head, the droplets of the one color are ejected from a head that faces the ejection target corresponding to the supplied one color. A droplet discharge method characterized by the above. The droplet discharge method according to claim 1 , wherein the second pitch is obtained by adding a pitch between the discharge target portions of different colors adjacent to the first pitch . The droplets are ejected in a state in which the plurality of nozzles provided in the first head, the second head, and the third head are arranged in a line perpendicular to the one direction. 3. The droplet discharge method according to claim 1 , wherein the method is performed while scanning one head, the second head, and the third head in the one direction . 4. The liquid droplets are discharged every time the second pitch and the first pitch are differentially scanned.
The droplet discharge method according to claim 3.

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