JP2007275808A - Pattern forming method, droplet discharging device and liquid crystal display device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pattern forming method and a droplet discharging device capable of avoiding positional deviation of a discharged droplet and thermal damage of a substrate and improving uniformity of a pattern made from droplets, and to provide a liquid crystal display device having liquid crystal discharged by the droplet discharging device. <P>SOLUTION: A first heater H1 and a second heater H2 are respectively disposed in the main scanning direction (anti X-arrow direction) of a discharging head 40 and in the direction (X-arrow direction) opposite to the main scanning direction. Therein, the first heater H1 heats a first heating region HA1 up to a first heating temperature (near the discharging temperature) and the second heater H2 heats a second heating region HA2 opposite to the first heating region HA1 up to the second heating temperature. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a pattern forming method, a droplet discharge device, and a liquid crystal display device.

  In general, a manufacturing process of a liquid crystal display device includes a sealing process in which a liquid crystal material is discharged to a discharge region provided on a substrate and the discharge region is sealed with a counter substrate. In this sealing process, in order to stabilize the discharge capacity of the liquid crystal material, an ink jet method is used in which the liquid crystal material is discharged as a plurality of droplets.

In the ink jet method, a liquid material interface (meniscus) formed on a discharge head is forcibly vibrated to form droplets. Therefore, when discharging a highly viscous liquid (for example, liquid crystal material), the flow path of the liquid is heated in advance to reduce the viscosity of the liquid (for example, Patent Document 1). As a result, the droplet discharge operation is stabilized and the droplet discharge capacity becomes uniform.
JP 2004-347695 A

However, when the heated liquid material is ejected as droplets, the following problems are caused due to temperature fluctuations of the liquid material or droplets.
That is, in the above-described ink jet method, the distance (platen gap) between the ejection head and the substrate is narrowed to about 1 mm in order to ensure the droplet landing accuracy. For this reason, when the ejection head is scanned with respect to the substrate, the heated liquid material releases the amount of heat to the substrate side, thereby changing the temperature. As a result, there is a problem in that the viscosity of the liquid to be discharged increases or decreases and the uniformity of the discharge capacity is impaired.

  Further, when the heated liquid material lands on the substrate as droplets, the amount of heat of the droplets is immediately taken away by the substrate, increasing its viscosity. Therefore, when forming a pattern of a liquid film composed of droplets, the discharged droplets thicken immediately after landing, making it difficult to bond the droplets, that is, the pattern thickness uniformity is impaired. there were.

  It is considered that these problems can be avoided by always heating the entire substrate in the step of ejecting droplets and suppressing the heat radiation of the ejected liquid or landed droplets. However, when the entire substrate is heated, the substrate may be thermally expanded to reduce the droplet landing accuracy. In addition, the heating time of the substrate becomes long, and various members (for example, a sealing member for enclosing a liquid crystal material) formed on the substrate may be thermally damaged.

  The present invention has been made to solve the above problems, and its purpose is to avoid the positional deviation of the ejected droplets and the thermal damage of the substrate, and to improve the uniformity of the pattern composed of the droplets. A pattern forming method, a droplet discharge device, and a liquid crystal display device.

According to the pattern forming method of the present invention, a discharge head that discharges a heated liquid into droplets and discharges it to the substrate is main-scanned relative to the substrate along the main scanning direction, and the discharge head scans the substrate. In the pattern forming method in which a pattern made of the liquid material is formed in an area, when the main scanning is performed, the pre-discharge scanning area located in the main scanning direction of the discharge head is close to the temperature of the heated liquid material In addition, the post-discharge scanning region located on the opposite side of the main scanning direction of the discharge head is locally heated to a temperature lower than the temperature of the pre-discharge scanning region.

  According to the pattern forming method of the present invention, the scanning area when facing the ejection head (scanning area before ejection) and the area of the liquid droplets landed on the scanning area (scanning area after ejection) are each localized. The temperature rises to Therefore, the scanning region when facing the ejection head suppresses the heat radiation of the liquid material in the ejection head and stabilizes the volume of the liquid material to be ejected. Further, the droplets that have landed on the scanning region are bonded while maintaining their fluidity, and the film thickness of the pattern made of the liquid material is made uniform. Then, the temperature rise over the entire substrate can be suppressed by the amount that the scanning region after ejection is set to a lower temperature than the scanning region before ejection. As a result, it is possible to avoid misalignment of the ejected droplets and thermal damage of the substrate, and to improve the capacity and shape uniformity of the pattern made of the droplets.

  In the pattern forming method, the ejection head is sub-scanned relative to the substrate along a sub-scanning direction orthogonal to the main scanning direction, and a plurality of the patterns are adjacent to each other along the sub-scanning direction. When the main scanning is performed, a boundary region between the scanning region after ejection and the pattern formed in advance adjacent to the scanning region after ejection is a temperature lower than the temperature of the scanning region before ejection. You may make it heat locally.

  According to this pattern formation method, it is possible to avoid displacement of the discharged droplets and thermal damage of the substrate, and to improve the uniformity of the film thickness and shape of the liquid material bonded in the sub-scanning direction.

  In the pattern forming method, when the main scanning is performed, the pre-ejection scanning area adjacent to the main scanning direction side of the ejection head is locally heated and the ejection head is opposite to the main scanning direction. The scanning area after ejection adjacent to the surface may be locally heated.

  According to this pattern forming method, it is possible to locally heat the scanning region immediately before facing the ejection head. As a result, heat dissipation from the liquid material of the ejection head can be more reliably suppressed by the amount of heat from the scanning region. In addition, local heating can be performed on the region of the droplet immediately after landing. As a result, the droplets can be efficiently bonded with a lower heating amount.

In the pattern forming method, when the main scanning is performed, the region to be heated may be main scanned relative to the substrate along the main scanning direction.
According to this pattern forming method, the area to be heated per unit time can be reduced with respect to the scanning area facing the ejection head and the area of the droplet that has landed on the scanning area. Therefore, it is possible to increase the temperature increase rate and the temperature decrease rate of the scanning region facing the ejection head and the droplet region landed on the scanning region. Therefore, the heating for each region can be controlled with higher accuracy. As a result, it is possible to more reliably avoid displacement of the discharged droplets and thermal damage to the substrate, and to improve the uniformity of the pattern made of the droplets more reliably.

A droplet discharge device according to the present invention includes a discharge head that discharges a heated liquid material to a substrate as a droplet, and main-scans the discharge head relative to the substrate along a main-scanning direction. And a main scanning means for forming a pattern made of the liquid material in a scanning region of the ejection head with respect to the liquid ejection device, disposed in the main scanning direction of the ejection head so as to face the substrate, A first heating unit that is main-scanned relative to the substrate together with the ejection head and locally heats the opposed scanning area before ejection near the temperature of the heated liquid material; and opposed to the substrate. As described above, the temperature of the scanning region before the ejection is set to be opposite to the main scanning direction of the ejection head, and the main scanning is performed relative to the substrate together with the ejection head. than A second heating means for locally heating the stomach temperature, with a.

  According to the liquid droplet ejection apparatus of the present invention, the scanning area when facing the ejection head (the scanning area before ejection) and the area of the liquid droplets landed on the scanning area (the scanning area after ejection) are each localized. Heated. Therefore, the scanning region which opposes suppresses the heat radiation of the liquid material in the discharge head and stabilizes the volume of the discharged liquid material. Further, the droplets that have landed on the scanning region are bonded while maintaining their fluidity, and the film thickness of the pattern made of the liquid material is made uniform. Then, the temperature rise over the entire substrate can be suppressed by the amount that the scanning region after ejection is set to a lower temperature than the scanning region before ejection. As a result, it is possible to avoid misalignment of the ejected droplets and thermal damage of the substrate, and to improve the capacity and shape uniformity of the pattern made of the droplets.

  In the droplet discharge device, the discharge head, the first heating unit, and the second heating unit may be relatively arranged with respect to the substrate along the sub-scanning direction orthogonal to the main scanning direction. A plurality of patterns that are adjacent to each other along the sub-scanning direction, and the second heating unit extends from the region of the ejection head to the opposite side of the sub-scanning direction when viewed from the main scanning direction. The boundary region between the scanning region after ejection and the pattern formed in advance adjacent to the scanning region after ejection is locally at a temperature lower than the temperature of the scanning region before ejection. You may make it heat to.

  According to this droplet discharge device, it is possible to avoid displacement of the discharged droplet and thermal damage to the substrate, and to improve the uniformity of the film thickness and shape of the pattern bonded in the sub-scanning direction.

  In the droplet discharge device, the first heating unit is adjacent to the main scanning direction side of the discharge head when viewed from the sub-scanning direction, and the second heating unit is the discharge head viewed from the sub-scanning direction. May be adjacent to the opposite side of the main scanning direction.

  According to this droplet discharge device, local heating can be performed on the scanning region immediately before facing the discharge head. As a result, heat dissipation from the liquid material of the ejection head can be more reliably suppressed by the amount of heat from the scanning region. In addition, local heating can be performed on the region of the droplet immediately after landing. As a result, the fluidity of the landed droplets can be maintained with a lower heating amount.

  Further, in this droplet discharge device, the substrate is a substrate that absorbs light in an infrared region, and the liquid material is a liquid material that absorbs light in an infrared region, and the first heating means The second heating unit may include a heater for irradiating light in the infrared region.

  According to this droplet discharge device, the substrate and the pattern can be heated in a non-contact manner by the light in the infrared region irradiated from the infrared heater. Therefore, the heating of the substrate and the pattern can be controlled with higher accuracy.

Moreover, in this droplet discharge device, the liquid material may be a liquid crystal material.
According to this droplet discharge device, it is possible to avoid displacement of the discharged droplets and thermal damage to the substrate, and to improve the uniformity of the pattern made of the liquid crystal material.

The liquid crystal display device of the present invention includes the liquid crystal material ejected by the droplet ejection device.
According to the liquid crystal display device of the present invention, it is possible to provide a liquid crystal material with improved capacity and shape uniformity.

  Hereinafter, an embodiment embodying the present invention will be described with reference to FIGS. First, the liquid crystal display device 10 of the present invention will be described. FIG. 1 is a perspective view of the liquid crystal display device 10, and FIG. 2 is a cross-sectional view taken along line AA of FIG.

  In FIG. 1, the liquid crystal display device 10 includes a square plate-like backlight 12 having LEDs 11 on the lower side thereof. Above the backlight 12, there is provided a liquid crystal panel 13 that is formed in a substantially the same square plate shape as the backlight 12 and is irradiated with light from the backlight 12.

  In FIG. 2, the liquid crystal panel 13 includes an element substrate 14 and a counter substrate 15 that face each other. The element substrate 14 and the counter substrate 15 are colorless and transparent glass substrates, and are bonded together by a rectangular frame-shaped sealing material 16 made of an ultraviolet light curable resin. A liquid crystal layer 17 made of a liquid crystal material F as a liquid is formed in the gap between the element substrate 14 and the counter substrate 15. The liquid crystal layer 17 is formed by the droplet discharge device of the present invention, and is uniformly filled without mixing bubbles or making the surface uneven. The liquid crystal material F has a viscosity at room temperature of 50 cP to 100 cP, absorbs light in the infrared region, and lowers the viscosity to less than 20 cP.

  An optical substrate 18 made of a polarizing plate, a retardation plate, or the like is bonded to the lower surface (side surface on the backlight 12 side) of the element substrate 14. The optical substrate 18 converts the light from the backlight 12 into linearly polarized light and emits it to the liquid crystal layer 17.

  On the upper surface of the element substrate 14 (side surface on the counter substrate 15 side: element formation surface 14a), as shown in FIG. ing. Each scanning line Lx is electrically connected to a scanning line driving circuit 19 formed on one side of the element substrate 14, and a scanning signal generated by the scanning line driving circuit 19 is input at a predetermined timing. A plurality of data lines Ly extending in the other direction (Y arrow direction) orthogonal to the X arrow direction are arranged on the element formation surface 14a. Each data line Ly is electrically connected to a data line driving circuit 21 formed on the other side of the element substrate 14, and a data signal generated by the data line driving circuit 21 is input at a predetermined timing.

  A plurality of pixels 22 connected to the corresponding scanning lines Lx and data lines Ly and arranged in a matrix are formed on the element formation surface 14a at positions where the scanning lines Lx and the data lines Ly intersect. . Each pixel 22 includes a control element such as a TFT and a light transmissive pixel electrode 23 made of a transparent conductive film. The control elements of each pixel 22 are selected one by one at a predetermined timing and turned on based on the line sequential scanning of the corresponding scanning line Lx. A data signal based on display data is input to each pixel electrode 23 when the control element of the corresponding pixel 22 is turned on.

  As shown in FIG. 2, an alignment film 24 subjected to an alignment process is stacked on the entire upper side of each pixel 22 (each pixel electrode 23). The alignment film 24 is formed of an alignment polymer such as alignment polyimide, and sets the alignment of liquid crystal molecules in a predetermined direction in the vicinity of the corresponding pixel electrode 23.

A polarizing plate 25 that emits linearly polarized light orthogonal to the light from the optical substrate 18 outward (upward in FIG. 2) is attached to the upper surface of the counter substrate 15. On the entire lower surface (electrode forming surface 15a) of the counter substrate 15, a counter electrode 26 made of a light-transmitting conductive film formed so as to face each pixel electrode 23 is laminated. The counter electrode 26 is electrically connected to the data line driving circuit 21 and receives a predetermined common potential generated by the data line driving circuit 21. An alignment film 27 that has been subjected to alignment treatment is laminated on the entire lower surface of the counter electrode 26, and the alignment of liquid crystal molecules is set in a predetermined direction in the vicinity of the counter electrode 26.

  The polarization state of light passing through the liquid crystal layer 17 is modulated for each pixel 22 based on a potential difference between each pixel electrode 23 and the counter electrode 26 when a data signal is input to each pixel electrode 23. . The modulated light in the polarization state displays an image based on the display data on the upper side of the liquid crystal panel 13 depending on whether or not it passes through the polarizing plate 25.

  In the displayed image, since the liquid crystal layer 17 is formed uniformly, that is, the distance (cell gap) between each pixel electrode 23 and the counter electrode 26 is formed uniformly, the luminance due to the variation in the cell gap. The display image quality is maintained without causing unevenness or color unevenness.

Next, a method for manufacturing the liquid crystal panel 13 will be described with reference to FIG. FIG. 3 is an explanatory diagram for explaining a method of manufacturing the liquid crystal panel 13.
As shown in FIG. 3, first, a sealing material 16 is provided on one side surface of the mother substrate MA from which the four counter substrates 15 can be cut out (side surface on the alignment film 27 side: ejection surface MAa) using a dispenser device or the like. Form. That is, a rectangular frame-shaped sealing material 16 made of an ultraviolet light curable resin is discharged and formed on the outer edge of a region corresponding to each counter substrate 15 formed on the discharge surface MAa. When each sealing material 16 is formed, a plurality of liquid droplets Fb are ejected to regions (each ejection region S) surrounded by each sealing material 16 using an inkjet device 30 as a droplet ejection device. Then, the droplets Fb that have landed on the discharge regions S are joined together, and a liquid film pattern made of a predetermined volume of the liquid crystal material F is formed in each discharge region S.

  When the pattern of the liquid crystal material F is formed in each ejection region S, the mother substrate MA is transported in a reduced-pressure atmosphere, and the mother substrate MB on which the four element substrates 14 can be cut out on the ejection surface MAa side of the mother substrate MA. to paste together. When the mother substrate MB is bonded to the mother substrate MA, the mother substrate MA and the mother substrate MB are opened to the atmosphere, and each sealing material 16 is irradiated with ultraviolet rays and cured, and the liquid crystal material F is sealed in each discharge region S. . When the liquid crystal material F is sealed, the mother substrate MA and the mother substrate MB are diced to form each liquid crystal panel 13. In the present embodiment, the width in the Y arrow direction of the discharge region S is defined as the discharge width WS.

Next, the ink jet apparatus 30 for discharging the liquid crystal material F will be described with reference to FIGS. FIG. 4 is a perspective view showing the inkjet device 30.
In FIG. 4, the ink jet apparatus 30 includes a base 31 formed in a rectangular parallelepiped shape. A pair of guide grooves 32 extending along the longitudinal direction (X arrow direction) is formed on the upper surface of the base 31. Above the guide groove 32, a transport table 33 is provided as main scanning means that moves forward and backward along the guide groove 32 in the X arrow direction and the counter X arrow direction. In the present embodiment, the anti-X arrow direction in FIG. 4 is defined as the main scanning direction.

  On the upper surface of the transfer table 33, there is formed a mounting portion 34 for mounting the mother substrate MA with each discharge region S on the upper side. The placement unit 34 positions and fixes the placed mother substrate MA with respect to the transport base 33, and transports the mother substrate MA in the X arrow direction and the counter X arrow direction.

  On both sides of the base 31 in the Y arrow direction, guide members 35 formed in a gate shape are installed so as to straddle the base 31. A storage tank 36 that extends in the direction of the arrow Y is disposed on the upper side of the guide member 35. The storage tank 36 stores the liquid crystal material F and guides the liquid crystal material F to the discharge head 40 disposed below at a predetermined pressure.

A pair of upper and lower guide rails 37 extending in the Y arrow direction is formed on the lower side of the guide member 35 over substantially the entire width in the Y arrow direction. A carriage 38 is attached to the pair of guide rails 37 as sub-scanning means that moves forward and backward along the guide rails 37 in the directions of the Y arrow and the anti-Y arrow. In the present embodiment, the Y arrow direction in FIG. 4 is defined as the sub-scanning direction.

  A first heater H1 as a first heating unit, a discharge head 40, and a second heater H2 as a second heating unit are mounted on the lower side of the carriage 38 in order from the side opposite to the arrow X. . FIG. 5 is a perspective view of the discharge head 40, the first heater H1, and the second heater H2 as viewed from the lower side (mother substrate MA side). 6 is a cross-sectional view taken along line AA in FIG. 7 and 8 are explanatory diagrams for explaining the scanning region of the ejection head 40 with respect to the mother substrate MA.

  As shown in FIG. 5, the ejection head 40 is formed in a rectangular parallelepiped shape extending in the Y arrow direction. A nozzle plate 41 is provided below the discharge head 40 (on the mother substrate MA side: the upper side in FIG. 5) so as to face the mother substrate MA. The nozzle plate 41 is formed in a plate shape extending in the Y arrow direction, and the width in the Y arrow direction is approximately half the size of the ejection width WS. In the present embodiment, the width of the nozzle plate 41 in the Y arrow direction is defined as the scanning width WH.

  As shown in FIGS. 5 and 6, a nozzle forming surface 41 a exposed to the mother substrate MA side is formed on the lower surface (upper surface in FIG. 5) of the nozzle plate 41. When the mother substrate MA is located immediately below the ejection head 40, the nozzle formation surface 41a has a predetermined distance (1 mm in this embodiment) between the nozzle formation surface 41a and the ejection surface MAa. To. On the nozzle forming surface 41a, a plurality of nozzles N are arranged at equal intervals over substantially the entire width in the Y arrow direction. Each nozzle N is formed penetrating in the normal direction of the nozzle forming surface 41a. In the present embodiment, in FIG. 6, positions on the ejection surface MAa of the mother substrate MA to be conveyed and positions facing each other directly below the nozzles N are defined as landing positions P, respectively.

  A head heater 42 is disposed on the outer periphery of the discharge head 40. The head heater 42 heats the liquid crystal material F from the storage tank 36 to a predetermined temperature (discharge temperature: 70 ° C. in the present embodiment), and lowers the viscosity (in this embodiment, reduced to 20 cP). Supply to the discharge head 40.

  As shown in FIG. 6, cavities 43 communicating with the storage tanks 36 are formed above the nozzles N, respectively. The cavity 43 supplies the liquid crystal material F from the storage tank 36 to the corresponding nozzle N. A vibration plate 44 is attached to the upper side of each cavity 43 to vibrate in the vertical direction so that the volume in the cavity 43 can be enlarged or reduced. A plurality of piezoelectric elements PZ corresponding to the nozzles N are disposed on the upper side of the vibration plate 44. Each piezoelectric element PZ contracts and expands in the vertical direction to vibrate the corresponding region of the vibration plate 44 in the vertical direction, and discharges the droplet Fb of the liquid crystal material F from the corresponding nozzle N. The discharged droplets Fb fly along the anti-Z arrow direction of the corresponding nozzle N and land at the corresponding landing position P. At this time, the ejection head 40 stabilizes the ejection operation as much as the head heater 42 sets the liquid crystal material F to the ejection temperature, and equalizes the volume of each droplet Fb to be ejected. Further, the ejection head 40 maintains the landing accuracy of each droplet Fb ejected from the nozzle forming surface 41a as much as the platen gap is maintained at a predetermined distance.

  In FIG. 7, when the mother substrate MA is transported in the X arrow direction, the ejection head 40 first faces in the main scanning direction (anti-X arrow direction) while facing the opposite Y arrow direction side of each ejection region S. A relatively scan (main scan) is performed. That is, the ejection head 40 forms a trajectory (the first scanning area SA1 constituting the scanning area) in which the width in the Y arrow direction is the scanning width WH with respect to the opposite Y arrow direction side of each ejection area S.

  Further, the ejection head 40 contracts and expands each piezoelectric element PZ when each landing position P is positioned at each lattice point defined in the ejection area S (first scanning area SA1), and the corresponding nozzle N From the liquid crystal material F. That is, the ejection head 40 forms a pattern (first liquid film LF1) of the liquid crystal material F composed of a plurality of droplets Fb in the region where the first scanning region SA1 and the ejection region S overlap.

  In FIG. 8, the ejection head 40 is relatively scanned (sub-scanned) by the scanning width WH in the sub-scanning direction after the mother substrate MA is transported in the X arrow direction (forming the first liquid film LF1). Thereafter, the main scanning is performed again. In other words, the ejection head 40 forms a locus (second scanning area SA2 constituting the scanning area) having the same size as the first scanning area SA1 adjacent to the first scanning area SA1 on the Y arrow direction side of each ejection area S. To do.

  The ejection head 40 contracts and expands each piezoelectric element PZ when each landing position P is located at each lattice point defined in the ejection area S (second scanning area SA2), and the corresponding nozzle N. From the liquid crystal material F. That is, the ejection head 40 forms a pattern (second liquid film LF2) of the liquid crystal material F in which a plurality of droplets Fb are joined in a region where the second scanning region SA2 and the ejection region S overlap.

  As shown in FIG. 5, the first heater H <b> 1 is formed in a rectangular parallelepiped shape that is substantially the same size as the ejection head 40. The first heater H1 is disposed in the anti-X arrow direction (main scanning direction) of the ejection head 40 so as to overlap the ejection head 40 when viewed from the main scanning direction.

  As shown in FIG. 6, the first heater H1 has a first irradiation surface H1a opposite to the mother substrate MA. The first irradiation surface H1a is disposed at the same height as the nozzle formation surface 41a. The first irradiation surface H1a locally irradiates light L1 in the infrared region having a high absorptivity with respect to the mother substrate MA toward the region of the mother substrate MA (first heating region HA1) facing each other. The first heating area HA1 is heated to a predetermined temperature (first heating temperature: 70 ° C. in the present embodiment).

The first heating temperature is set in the vicinity of the discharge temperature and suppresses heat radiation from the liquid crystal material F of the discharge head 40 to the mother substrate MA.
As shown in FIG. 7 and FIG. 8, the first heater H1 precedes the main scanning direction of the ejection head 40 when the ejection head 40 forms the first scanning area SA1 and the second scanning area SA2. Scanned relative to MA. That is, the first heater H1 locally raises the temperature of the first scanning area SA1 or the second scanning area SA2 (scanning area before ejection) immediately before reaching the landing position P (set to the first heating temperature).

  For this reason, the liquid crystal material F of the ejection head 40 has its mother substrate MA locally heated to the first heating temperature (near the ejection temperature) when the droplet Fb is ejected. Heat dissipation to the substrate MA is suppressed. That is, the liquid crystal material F of the discharge head 40 maintains its viscosity and makes the discharge capacity uniform. Furthermore, each droplet Fb that lands on the mother substrate MA lands on the ejection surface MAa in the vicinity of the ejection temperature, so that thickening after landing is suppressed and spreads wet along the surface direction of the ejection surface MAa. As a result, a predetermined volume of the first liquid film LF1 and the second liquid film LF2 in which a plurality of droplets Fb are joined to each other are uniformly formed at different timings in the first scanning area SA1 and the second scanning area SA2.

As shown in FIG. 5, the second heater H2 is formed in a rectangular parallelepiped shape whose width in the Y arrow direction is longer than the width of the first heater H1 in the Y arrow direction. The second heater H2 overlaps with the entire ejection head 40 when viewed from the main scanning direction, and extends in the direction of the arrow Y opposite to the ejection head 40 (the direction opposite to the sub-scanning direction). It is disposed on the opposite side of the main scanning direction.

  As shown in FIG. 6, the second heater H2 has a second irradiation surface H2a opposite to the mother substrate MA. The second irradiation surface H2a is disposed at the same height as the nozzle formation surface 41a. The second irradiation surface H2a locally irradiates the light L2 in the infrared region having a high absorptivity with respect to the liquid crystal material F toward the region of the mother substrate MA facing (second heating region HA2). The second heating area HA2 is heated to a predetermined temperature (second heating temperature: 40 ° C. in the present embodiment).

  The second heating temperature is a temperature set in advance based on a test or the like, and the second heating temperature is around the boundary between the first liquid film LF1 formed in advance and the second liquid film LF2 just after formation. (Boundary area JA) is joined uniformly. That is, the second heating temperature is a temperature that imparts fluidity to the previously formed first liquid film LF1 again and enables bonding with the second liquid film LF2 immediately after formation. Therefore, the second heating temperature is lower than the discharge temperature (first heating temperature), and is set to a lower temperature by the amount that the second liquid film LF2 is preheated to the first heating temperature. .

  As shown in FIG. 7, the second heater H2 is scanned relative to the first liquid film LF1 along the main scanning direction when the ejection head 40 forms the first scanning region SA1. That is, the second heater H2 follows the ejection head 40 and locally raises the temperature of the first liquid film LF1 (scanned area after ejection) immediately after formation (set to the second heating temperature). Therefore, the first liquid film LF1 immediately after the formation retains the fluidity immediately after the landing by the heating amount of the second heater H2, and further spreads out in the surface direction of the discharge surface MAa.

  As shown in FIG. 8, the second heater H2 is scanned relative to the second liquid film LF2 along the main scanning direction when the ejection head 40 forms the second scanning region SA2. That is, the second heater H2 follows the ejection head 40 and locally raises the temperature of the second liquid film LF2 (scanning area after ejection) immediately after formation (set to the second heating temperature). Therefore, the second liquid film LF2 immediately after the formation retains the fluidity immediately after the landing by the heating amount of the second heater H2, and further wets and spreads along the surface direction of the ejection surface MAa. In addition, the second heater H2 is scanned relative to the boundary area JA between the first liquid film LF1 and the second liquid film LF2 along the main scanning direction. That is, the second heater H2 locally heats the first liquid film LF1 adjacent to the second liquid film LF2 immediately after formation (heats to the second heating temperature), and the first liquid film LF1 The fluidity for joining with the second liquid film LF2 is imparted.

  As a result, the first liquid film LF1 and the second liquid film LF2 immediately after the formation can be uniformly bonded by the second heating temperature lower than the first heating temperature, and the second heating temperature is lowered. Only the temperature rise throughout the mother substrate MA is suppressed.

Next, the electrical configuration of the inkjet apparatus 30 configured as described above will be described with reference to FIG.
In FIG. 9, the control device 50 includes a CPU, a RAM, a ROM, and the like, reciprocates the carriage 33 and the carriage 38 according to various stored data and various control programs, and controls the driving of each piezoelectric element PZ. And heating control of the first heater H1 and the second heater H2.

  An input device 51 having operation switches such as a start switch and a stop switch is connected to the control device 50, and the position coordinates of each discharge region S and the discharge capacity for each discharge region S are input as discharge data Ia in a predetermined format. Is done. The control device 50 receives the ejection data Ia from the input device 51 and generates bitmap data BMD.

  Bitmap data BMD defines ON or OFF of each piezoelectric element PZ according to the value (0 or 1) of each bit, and droplets are applied to respective positions on the two-dimensional drawing plane (ejection surface MAa). This is data defining whether or not to discharge Fb. That is, the bitmap data BMD is for discharging the droplets Fb to the respective lattice points defined in each discharge region S.

  An X-axis motor drive circuit 52 is connected to the control device 50 and outputs a drive control signal corresponding to the X-axis motor drive circuit 52. In response to the drive control signal from the control device 50, the X-axis motor drive circuit 52 rotates the X-axis motor MX for reciprocating the transport table 33 in the forward or reverse direction. The control device 50 conveys the mother board MA in the X arrow direction and the counter X arrow direction via the X-axis motor drive circuit 52.

  A Y-axis motor drive circuit 53 is connected to the control device 50 and outputs a drive control signal corresponding to the Y-axis motor drive circuit 53. In response to the drive control signal from the control device 50, the Y-axis motor drive circuit 53 rotates the Y-axis motor MY for reciprocating the carriage 38 in the forward or reverse direction. The control device 50 performs sub-scanning on the carriage 38 via the Y-axis motor drive circuit 53.

  A substrate detection device 54 capable of detecting the edge of the mother substrate MA is connected to the control device 50, and the position of the mother substrate MA with respect to each landing position P is calculated based on a detection signal from the substrate detection device 54. Used for.

  The control device 50 is connected to an X-axis motor rotation detector 55 and receives a detection signal from the X-axis motor rotation detector 55. Based on the detection signal from the X-axis motor rotation detector 55, the control device 50 calculates the movement direction and the movement amount of the transport table 33 (mother substrate MA). The control device 50 outputs a discharge timing signal LP to the discharge head drive circuit 57 every time each landing position P is positioned at each grid point of the discharge region S.

  The control device 50 is connected to a Y-axis motor rotation detector 56 and receives a detection signal from the Y-axis motor rotation detector 56. The control device 50 calculates the movement direction and movement amount of the carriage 38 (each nozzle N) in the Y arrow direction based on the detection signal from the Y-axis motor rotation detector 56. The control device 50 arranges each landing position P on the main scanning path of each lattice point of the ejection region S.

  A discharge head drive circuit 57 is connected to the control device 50 and outputs a discharge timing signal LP. The control device 50 outputs a signal (piezoelectric element drive voltage COM) for driving the piezoelectric element PZ to the ejection head drive circuit 57 in synchronization with the ejection timing signal LP. The control device 50 generates a discharge control signal SI synchronized with a predetermined clock signal based on the bitmap data BMD corresponding to one main scan of the discharge head 40, and uses the discharge control signal SI as the discharge head. Serial transfer to the drive circuit 57 is performed. The ejection head drive circuit 57 sequentially converts the ejection control signal SI from the control device 50 into serial / parallel conversion corresponding to each piezoelectric element PZ. Each time the ejection head drive circuit 57 receives the ejection timing signal LP from the control device 50, the ejection head drive circuit 57 supplies the piezoelectric element drive voltage COM to the piezoelectric element PZ selected based on the ejection control signal SI subjected to serial / parallel conversion.

  A heater drive circuit 58 is connected to the control device 50 and outputs a heater drive signal SL for driving the first heater H1 and the second heater H2. The heater drive circuit 58 receives the heater drive signal SL from the control device 50 and starts heating by the first heater H1 and the second heater H2 before the ejection head 40 is main-scanned.

Next, a method for discharging the liquid crystal material F using the inkjet device 30 will be described.
First, as shown in FIG. 4, the mother substrate MA is placed on the transport table 33 so that the ejection surface MAa is on the upper side. At this time, the mother substrate MA is arranged on the side opposite to the X arrow direction from the carriage 38.

  From this state, the discharge data Ia is input from the input device 51 to the control device 50, and the control device 50 generates and stores bitmap data BMD based on the discharge data Ia. Next, when the mother substrate MA is transported in the X arrow direction, the control device 50 moves the carriage 38 via the Y-axis motor drive circuit 53 so that the ejection head 40 forms the first scanning region SA1. The discharge head 40, the first heater H1, and the second heater H2 are disposed. Further, the control device 50 outputs a heater drive signal SL to the heater drive circuit 58, and starts heating the first heater H1 and the second heater H2.

  When the heating state of the first heater H1 and the second heater H2 is stabilized, the control device 50 starts the main scan of the discharge head 40 via the X-axis motor drive circuit 52, and the discharge control signal SI corresponding to the main scan. Is output to the ejection head drive circuit 57. Further, the control device 50 determines whether or not each lattice point of the ejection region S is located at the corresponding landing position P based on detection signals from the substrate detection device 54 and the X-axis motor rotation detector 55. That is, the control device 50 outputs the ejection timing signal LP to the ejection head drive circuit 57 every time each grid point of the ejection area S is located at the corresponding landing position P. When the ejection timing signal LP is output, the ejection head drive circuit 57 supplies the piezoelectric element drive voltage COM to each piezoelectric element PZ selected based on the ejection control signal SI, and the liquid is simultaneously supplied from the selected nozzles N. The droplet Fb is discharged.

  While each droplet Fb is being discharged, the first heater H1 locally precedes the region of the mother substrate MA that opposes the discharge head 40 in the main scanning direction and immediately before the discharge operation. Heat (heat to the first heating temperature). As a result, the liquid crystal material F of the ejection head 40 suppresses heat radiation to the mother substrate MA, and makes the ejection capacity of each ejected droplet Fb uniform. Further, each droplet Fb ejected with a uniform volume lands on the mother substrate MA having substantially the same temperature as the temperature at the time of ejection and spreads.

  Further, while each droplet Fb is ejected, the second heater H2 follows on the opposite side of the ejection head 40 in the main scanning direction and locally heats the first liquid film LF1 immediately after formation (second heating). Rise to temperature). As a result, a uniform first liquid film LF1 in which the droplets Fb are joined is formed in the first scanning region SA1.

  Next, when the first liquid film LF1 is formed, the control device 50 ends the main scanning of the ejection head 40, transports the mother substrate MA in the direction of the anti-X arrow, and again moves the mother substrate MA to the carriage 38. It arranges on the anti-X arrow direction side. Further, when the controller 50 moves the carriage 38 via the Y-axis motor drive circuit 53 and transports the mother substrate MA in the X arrow direction, the ejection head 40 forms the second scanning region SA2. The ejection head 40, the first heater H1, and the second heater H2 are sub-scanned.

  Next, the control device 50 starts the main scanning of the ejection head 40 again via the X-axis motor driving circuit 52 and outputs the ejection control signal SI corresponding to the main scanning to the ejection head driving circuit 57. Further, the control device 50 causes the droplets Fb to be ejected simultaneously from the nozzles N selected based on the ejection control signal SI every time each lattice point of the ejection region S is located at the corresponding landing position P. As a result, a uniform second liquid film LF2 in which the droplets Fb are joined is formed on the side of the sub-scanning direction of each ejection region S along the main scanning direction, like the first liquid film LF1.

  While the second liquid film LF2 is formed, the second heater H2 follows the anti-main scanning direction of the ejection head 40, and the second liquid film LF2 just formed and the first formed in advance corresponding to the boundary area JA. One liquid film LF1 is locally heated (heated to the second heating temperature). As a result, a pattern in which the first liquid film LF1 and the second liquid film LF2 are uniformly bonded is formed in the ejection region S.

In addition, at this time, the temperature increase over the entire mother substrate MA is suppressed by the amount that the second heating area HA2 is heated to a temperature lower than the temperature of the first heating area HA1.
Thereafter, similarly, the control device 50 repeats the main scanning and the sub scanning relative to the mother substrate MA of the ejection head 40, the first heater H1, and the second heater H2. At this time, the controller 50 scans both the first heating area HA1 and the second heating area HA2 along the main scanning direction when the ejection head 40 is main scanned. As a result, the first liquid film LF1 and the second liquid film LF2 adjacent to each other are uniformly bonded, and a pattern of the liquid crystal material F having a uniform film thickness is formed in the entire ejection region S.

Next, effects of the embodiment configured as described above will be described below.
(1) According to the above embodiment, the first heater H1 and the second heater H2 are disposed in the opposite direction of the main scanning direction and the main scanning direction of the ejection head 40, respectively. Then, the first heater H1 raises the temperature of the opposing first heating area HA1 to the first heating temperature (near the discharge temperature). In addition, the second heater H2 raises the temperature of the opposing second heating area HA2 to a second heating temperature lower than the first heating temperature.

  Therefore, before discharging the droplet Fb to the first scanning area SA1 (second scanning area SA2), the corresponding first scanning area SA1 (second scanning area SA2) is locally increased to the first heating temperature in advance. Can be warmed. Therefore, the viscosity of the liquid crystal material F can be stabilized, and the capacity uniformity of the first liquid film LF1 (second liquid film LF2) can be improved.

  Further, after ejecting the droplet Fb to the first scanning area SA1 (second scanning area SA2), the corresponding first scanning area SA1 (second scanning area SA2) is locally heated to the second heating temperature. be able to. Therefore, the landed droplet Fb can be wetted and spread in the first scanning region SA1 (second scanning region SA2), and the film thickness uniformity of the first liquid film LF1 (second liquid film LF2) can be improved. it can.

  And the temperature increase over the whole mother board | substrate MA can be suppressed by the part which sets 1st heating temperature lower than 2nd heating temperature. As a result, it is possible to avoid misalignment of the discharged droplets Fb and thermal damage of the mother substrate MA, and to form the uniform liquid crystal layer 17 over the entire discharge region S.

  (2) Furthermore, the second heater H2 is formed so as to extend in the anti-Y arrow direction (the direction opposite to the sub-scanning direction) of the ejection head 40, and the boundary area JA between the first liquid film LF1 and the second liquid film LF2. Is heated locally to raise the temperature to the second heating temperature. Therefore, the first liquid film LF1 formed in advance and the subsequent second liquid film LF2 can be uniformly bonded at the second heating temperature lower than the first heating temperature.

  As a result, it is possible to avoid misalignment of the discharged droplets Fb and thermal damage of the mother substrate MA, and to form a more uniform liquid crystal layer 17 over the entire discharge region S.

(3) According to the above embodiment, the first heater H1 is adjacent to the main scanning direction side of the ejection head 40, and the second heater H2 is adjacent to the opposite side of the ejection head 40 in the main scanning direction. for that reason,
Immediately before forming the first liquid film LF1 and the second liquid film LF2, the corresponding first scanning area SA1 and second scanning area SA2 can be heated to the first heating temperature. Further, immediately after forming the second liquid film LF2, the region of the first liquid film LF1 joined to the second liquid film LF2 can be raised to the second heating temperature.

As a result, the first liquid film LF1 and the second liquid film LF2 that are bonded to each other can be made more efficient and uniform.
(4) According to the above embodiment, the first heater H <b> 1 and the second heater H <b> 2 are mounted on the same carriage 38 as the ejection head 40. Therefore, when the ejection head 40 is main-scanned relatively with respect to the mother substrate MA, the first heater H1 and the second heater H2 respectively pass the first heating area HA1 and the second heating area HA2 to the ejection area S. The main scanning is performed relatively to Therefore, the temperature increase rate and the temperature decrease rate for the mother substrate MA, the first liquid film LF1, and the second liquid film LF2 can be increased by the amount of main scanning of the local heating region.

  As a result, the temperatures of the mother substrate MA, the first liquid film LF1 and the second liquid film LF2 can be controlled with higher accuracy, and the positional deviation of the discharged droplets and the thermal damage of the mother substrate MA can be further reduced. It can be surely avoided.

  (5) According to the above-described embodiment, the first heater H1 and the second heater H2 irradiate the light L1 and the light L2 in the infrared region to the first heating region HA1 and the second heating region HA2 that face each other. Therefore, the mother substrate MA, the first liquid film LF1, and the second liquid film LF2 can be heated in a non-contact manner. Therefore, the temperatures of the mother substrate MA, the first liquid film LF1, and the second liquid film LF2 can be controlled with higher accuracy.

In addition, you may change the said embodiment as follows.
In the above embodiment, the width of the second heater H2 in the Y arrow direction is made smaller than the width of the first heater H1 in the Y arrow direction. Not limited to this, the width of the second heater H2 in the Y arrow direction is made smaller than the width of the first heater H1 (discharge head 40) in the Y arrow direction, and only the boundary region JA is heated to the second heating temperature. It may be configured.

According to this, the bonding between the first liquid film LF1 and the second liquid film LF2 can be made uniform by a smaller heating region.
In the above embodiment, the case where the pattern of the liquid crystal material F (the first liquid film LF1 and the second liquid film LF2) is formed in each ejection region S by two main scans has been described. For example, the pattern of the liquid crystal material F may be formed by three or more main scans. That is, any structure may be used as long as the previously formed liquid pattern is locally heated and the pattern is joined to another adjacent pattern.
In the above embodiment, the sealing material 16 is formed on the mother substrate MA, and the droplet Fb of the liquid crystal material F is discharged onto the mother substrate MA. For example, the sealing material 16 may be formed on the mother substrate MB, and the droplet Fb may be discharged onto the mother substrate MB.
In the above embodiment, the bitmap data BMD is generated based on the ejection data Ia. However, the present invention is not limited to this, and the configuration may be such that bitmap data BMD previously generated by an external device is input from the input device 51 to the control device 50.
In the above embodiment, the ejection head 40, the first heater H1, and the second heater H2 are arranged and fixed, and the mother substrate MA is moved. For example, the mother substrate MA may be arranged and fixed, and the ejection head 40, the first heater H1, and the second heater H2 may be moved. That is, it is sufficient if the ejection head 40, the first heater H1, and the second heater H2 are configured to perform main scanning relative to the substrate along the main scanning direction. Further, the discharge head 40, the first heater H1, and the second heater H2 may be configured to perform sub-scanning relative to the substrate along the sub-scanning direction.
In the above embodiment, the first heating means and the second heating means are each embodied as an infrared heater. Not limited to this, for example, the first heating means and the second heating means may be embodied as a resistance heater, as long as the corresponding liquid can be reduced in viscosity by local heating.
In the above embodiment, the case where the liquid crystal material F of 50 cP to 100 cP is discharged has been described. However, the present invention is not limited to this, and a liquid crystal material F of less than 50 cP or a liquid crystal material F higher than 100 cP may be discharged. Furthermore, the structure which discharges the metal ink containing a metal microparticle may be sufficient. That is, the liquid material of the present invention may be a liquid material that can be bonded by reducing the viscosity by local heating.
In the above embodiment, the liquid crystal display device 10 is embodied as an active matrix transmissive liquid crystal display device. For example, the liquid crystal display device 10 may be embodied as a reflection / transmission liquid crystal display device or a passive liquid crystal display device. That is, the liquid crystal display device only needs to enclose the liquid crystal layer 17 between the element substrate 14 and the counter substrate 15.
In the above embodiment, the liquid crystal layer 17 (the liquid crystal display device 10) is manufactured by discharging the liquid crystal material F. For example, the liquid material may be embodied in metal ink, and various metal wirings of the liquid crystal display device 10 may be formed. In addition, a planar electron-emitting device may be provided, and various metal wirings of a field effect device (FED, SED, etc.) using light emission of a fluorescent material by electrons emitted from the device may be formed. . In other words, any structure may be used as long as the pattern is formed by liquid droplets.
In the above embodiment, the droplet discharge device is embodied in the inkjet device 30. However, the present invention is not limited to this, and may be embodied in a dispenser device as long as the device forms a pattern on a substrate by discharging liquid droplets.

The perspective view of the liquid crystal display device of this embodiment. Similarly, sectional drawing of a liquid crystal display device. Similarly, explanatory drawing explaining the manufacturing method of a liquid crystal display. Similarly, the perspective view of a droplet discharge device. Similarly, the perspective view of an ejection head. Similarly, the sectional side view of an ejection head. Similarly, an explanatory view for explaining a scanning region of the ejection head. FIG. Similarly, an explanatory view for explaining a scanning region of the ejection head. FIG. Similarly, the electric block circuit diagram for demonstrating the electrical structure of a droplet discharge apparatus.

Explanation of symbols

  H1 ... first heater as first heating means, H2 ... second heater as second heating means, JA ... boundary region, L1, L2 ... light, MA ... mother substrate as substrate, F ... liquid crystal as liquid material Material, Fb ... droplet, SA1 ... first scanning area constituting the scanning area, SA2 ... second scanning area constituting the scanning area, 10 ... liquid crystal display device, 17 ... liquid crystal layer as a pattern, 30 ... droplet ejection Inkjet device as a device, 40... Discharge head.

Claims (10)

A pattern formed of the liquid material in a scanning region of the discharge head with respect to the substrate is subjected to main scanning with respect to the substrate along a main scanning direction in a main scanning direction. In the pattern forming method for forming
During the main scanning, the pre-ejection scanning region located in the main scanning direction of the ejection head is locally heated near the temperature of the heated liquid material, and on the opposite side of the ejection head to the main scanning direction. A pattern forming method, wherein a scanning region after ejection that is positioned is locally heated to a temperature lower than the temperature of the scanning region before ejection. In the pattern formation method of Claim 1,
The ejection head is sub-scanned relatively to the substrate along a sub-scanning direction orthogonal to the main scanning direction, and a plurality of the patterns are adjacent along the sub-scanning direction,
When performing the main scanning, a boundary region between the scanning region after the ejection and the pattern formed in advance adjacent to the scanning region after the ejection is set to a temperature lower than the temperature of the scanning region before the ejection. A pattern forming method characterized by heating locally. In the pattern formation method of Claim 1 or 2,
When the main scanning is performed, the pre-ejection scanning region adjacent to the main scanning direction side of the ejection head is locally heated, and the post-ejection scanning is adjacent to the opposite side of the ejection head in the main scanning direction. A pattern forming method, wherein a region is locally heated. In the pattern formation method as described in any one of Claims 1-3,
A pattern forming method characterized in that, during the main scanning, the region to be heated is subjected to main scanning relatively to the substrate along the main scanning direction. A discharge head for discharging the heated liquid into droplets and discharging it to the substrate;
A liquid comprising: main scanning means for performing main scanning relative to the substrate along the main scanning direction with respect to the discharge head, and forming a pattern made of the liquid material in a scanning region of the discharge head with respect to the substrate. In the droplet ejection device,
The liquid material is disposed in the main scanning direction of the ejection head so as to face the substrate, and is subjected to main scanning relative to the substrate together with the ejection head, and the opposed scanning region before ejection is heated. First heating means for locally heating in the vicinity of the temperature of
The discharge head is disposed on the opposite side of the main scanning direction of the discharge head so as to face the substrate, and the main scanning is performed relative to the substrate together with the discharge head, and a scanning region after discharge facing the discharge head is discharged. Second heating means for locally heating to a temperature lower than the temperature of the previous scanning region;
A droplet discharge apparatus comprising: In the droplet discharge device according to claim 5,
The ejection head, the first heating unit, and the second heating unit are sub-scanned relative to the substrate along a sub-scanning direction orthogonal to the main scanning direction, and a plurality of the patterns are formed. Sub-scanning means adjacent along the sub-scanning direction,
The second heating means is formed so as to extend from the area of the ejection head to the opposite side of the sub-scanning direction when viewed from the main scanning direction, and in the scanning area after ejection and the scanning area after ejection A droplet discharge apparatus, wherein a boundary region between adjacent adjacent patterns is locally heated to a temperature lower than a temperature of a scanning region before discharge. The droplet discharge device according to claim 6,
The first heating means is adjacent to the main scanning direction side of the ejection head as viewed from the sub-scanning direction,
The liquid droplet ejection apparatus, wherein the second heating unit is adjacent to the opposite side of the main scanning direction of the ejection head as viewed from the sub-scanning direction. In the droplet discharge device according to any one of claims 5 to 7,
The substrate is a substrate that absorbs light in the infrared region,
The liquid is a liquid that absorbs light in the infrared region,
The liquid droplet ejection apparatus, wherein each of the first heating unit and the second heating unit includes a heater that irradiates light in an infrared region. In the droplet discharge device according to any one of claims 5 to 8,
A liquid droplet ejection apparatus, wherein the liquid material is a liquid crystal material. A liquid crystal display device comprising a liquid crystal material ejected by the droplet ejection device according to claim 9.

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