WO2006118088A1 - Paste application device and paste application method - Google Patents

Abstract

A paste application device (10) has a pump means (32) for discharging, from a nozzle (33), a paste of a quantity according to the rotation speed of a motor (41); movement devices (17, 18) for moving, relative to each other, the nozzle (33) and a substrate (31) along a substrate surface; and a control device for controlling the motor (41) of the pump means (32) and the movement devices (17, 18).

Description

 Specification

 Paste coating apparatus and paste coating method

 Technical field

 TECHNICAL FIELD [0001] The present invention relates to a paste coating apparatus and a paste coating method for applying a paste for sealing a liquid substance such as liquid crystal between glass substrates such as a liquid crystal display panel.

 Background art

 As a technique for drawing a pattern with a paste on a glass substrate, a pattern is drawn by moving one of the substrate and the nozzle in a horizontal plane parallel to the other while discharging nozzle force paste. The method is known.

 [0003] In the above method, the conventional paced coating apparatus discharges a paste-like sealant from a nozzle (needle) by applying a gas pressure of a preset pressure in a syringe as disclosed in Patent Document 1. And apply onto the substrate. At this time, the stage holding the substrate on the upper surface is moved in parallel with the nozzle.

 Patent Document 1: Japanese Patent Laid-Open No. 11-119232

 Disclosure of the invention

 [0004] In the method in which the paste-like sealant is discharged from the nozzle by gas pressure while the force is applied, if the gap between the upper surface of the substrate and the nozzle fluctuates, the discharge resistance of the sealant from the nozzle fluctuates and seals. The discharge amount of the agent changes. Also, when the viscosity of the sealant changes due to changes in ambient temperature, the discharge rate from the nozzle changes. As a result, there is a problem that the base cannot be applied to the target portion with the necessary amount.

 [0005] Also, as shown in FIG. 6, when the drawing speed of the pattern 109, that is, the moving speed of the stage or the head becomes high, the head or the head moves up and down due to the sudden acceleration / deceleration of the stage or the head near the corner. Vibration occurs, which causes a gap between the substrate and the nozzle to fluctuate, resulting in a pattern cut 110 and a coating amount variation 111.

[0006] For this reason, it is conceivable to reduce the head vibration near the corner by reducing the drawing speed in front of the corner in advance, thereby preventing pattern cuts and coating amount variation 111. However, in order to keep the amount of sealant discharged per unit time constant, If the drawing speed is slowed because the pressure gas is supplied inside, the coating amount of the slowed portion 112 increases as shown in FIG.

 [0007] Therefore, when a liquid crystal display panel is made by bonding two substrates together, the sealant of the portion 112 of the pattern 109 where the coating amount is partly large is not sufficiently crushed, and the interval between the two substrates is not sufficient. The width of the sealant that becomes non-uniform or is crushed in that part becomes wider than in other parts, causing problems such as protruding beyond a predetermined location.

 In order to prevent these problems, it is conceivable to reduce the gas pressure in the syringe at the same time as reducing the drawing speed near the corner of the pattern 109. In general, however, gas has a large compressibility (the volume is likely to decrease when pressure is applied, which is a property), and therefore the responsiveness from when the gas pressure is changed until the discharge rate changes is poor. The response time also varies depending on the remaining amount of sealant in the syringe. In addition, due to poor responsiveness, there is a problem that the application amount becomes too small at the application start point 113 and the application amount becomes excessive at the application end point 114.

 [0009] An object of the present invention is to apply a paste in a necessary amount to a target portion on a substrate.

 [0010] The present invention relates to a cylinder having a nozzle in a paste coating apparatus that discharges a paste for sealing a liquid substance between two substrates from a nozzle and applies the paste to at least one substrate, and the cylinder A pump means having a screw which is rotatably provided in the nozzle and discharges a paste of an amount corresponding to the rotation amount from the nozzle, a motor for rotating the screw, and the nozzle and the substrate on the substrate surface. A moving device that relatively moves along the motor, a motor of the pump means, and a control device that controls the moving device.

[0011] The present invention relates to a paste application method in which a paste for sealing a liquid substance between two substrates is ejected from a nozzle and applied to at least one of the substrates, depending on the amount of rotation of the screw. When the paste is applied to the substrate by discharging the paste from the nozzle by a pumping means for discharging a predetermined amount of paste from the nozzle, the paste is applied to the substrate with a predetermined application amount. The rotation of the screw is controlled. Brief Description of Drawings

 FIG. 1 is an overall view showing a paced coating apparatus.

 FIG. 2 is an enlarged schematic view of the discharge pump of FIG.

 FIG. 3 is a schematic diagram for explaining a coating operation.

 FIG. 4 is a diagram showing the relationship between the application position and the speed of the motor of the discharge pump.

 FIG. 5 is a schematic diagram for explaining a coating pattern of a sealing agent in a concave portion of a conventional example.

 FIG. 6 is a schematic diagram showing an application pattern of a sealing agent of a conventional example.

 FIG. 7 is a schematic view showing a coating pattern of a conventional sealing agent.

 FIG. 8 is a schematic view showing another example of a cylinder and a screw in the discharge pump. BEST MODE FOR CARRYING OUT THE INVENTION

 A paste coating apparatus 10 according to the present invention shown in FIG. 1 has a square plate-like base 11, and the base 11 is fixed on four legs 12. A feed table 13 in the X-axis direction (left-right direction in FIG. 1) is provided on the upper surface of the base 11 so as to be movable in the left-right direction via the feed mechanism 14. The Y-axis is placed on the feed table 13 in the X-axis direction. A feed table 15 in the direction (front-rear direction in FIG. 1) is provided so as to be movable in the front-rear direction via a feed mechanism 16.

 [0014] A gate-shaped column 20 is fixed on the base 11, and two heads 22 are arranged in the left-right direction on a linear guide 21 fixed to the front portion of the horizontal beam portion 20A extending in the X-axis direction of the column 20. The two heads 22 are provided so as to be movable in the X-axis direction (left-right direction) via the feed mechanism 23. As a result, the distance in the X-axis direction between the two heads 22 can be matched to the arrangement distance in the X-axis direction of a plurality of patterns formed on the substrate 31 described later.

 [0015] The feed mechanisms 14, 16, and 23 each include a feed screw and a nut (not shown), and servo motors 24, 25, and 26 for driving that rotate the feed screw. The feeding mechanism may be a linear stator and a linear motor having a mover force that moves on the stator.

 A square plate-like stage 30 is fixed on the feed table 15 in the Y-axis direction, and a glass substrate 31 of a liquid crystal display panel is held on the stage 30.

[0017] Each of the two heads 22 has a discharge pump 32 (pump means) not shown in the Z-axis direction. The moving device (Z-axis moving device) is provided. As shown in FIG. 2, the discharge pump 32 is provided in parallel with a hollow cylinder 34 having a nozzle 33 at the tip and a screw 36 and a cylinder 34 that are rotatably provided in the cylinder 34 via a connecting member 35. 40 storage container.

 [0018] The screw 36 has a screw portion 36A on the outer periphery, and is connected to a servo motor 41 for driving fixed to the base end portion of the cylinder 34. A liquid sealing agent 44 (paste) is stored in the storage container 40, and a pressure gas chamber 45 is provided above the sealing agent 44. The pressure gas chamber 45 is connected to a gas pressure source (not shown) via a hose 46. Connected.

 [0019] In the pressure gas chamber 45, the supply of the pressure gas from the gas pressure source is started at a timing earlier than the timing at which the rotation of the screw 36 is started, and the rotation of the screw 36 is stopped. It stops at the timing.

 [0020] The bottom of the storage container 40 is connected to an opening 43 in the upper part of the cylinder 34 via a noise 42, and the opening 43 in the upper part of the cylinder 34 opens toward the outer periphery of the upper end of the screw part 36A of the screw 36. A spiral liquid chamber filled with a sealant is formed between the inner periphery of the cylinder 34 and the upper and lower screw portions 36A. Here, in order to fill the liquid chamber with the sealant, the following is performed as a preliminary discharge operation.

 That is, the pressure gas is supplied into the pressure gas chamber 45, and the screw 36 is rotated in this state. The screw 36 continues to rotate until the liquid chamber is filled with the sealant and the sealant is discharged from the nozzle 33. At this time, it is preferable that the screw 36 is continuously rotated for a set time after the sealant is discharged from the nozzle, so that the sealant can be filled in the liquid chamber without leaving air in the liquid chamber.

 The discharge pump 32 has a distance measuring device such as a laser displacement meter (not shown) provided integrally with the nozzle 33. The control device described later controls the gap between the nozzle 33 and the surface of the substrate 31 so as to keep a predetermined gap by feedback control based on the measured value of the distance to the surface of the substrate 31 by the distance measuring device (gap Control.

[0023] When the motor 41 of the discharge pump 32 is rotated, the screw 36 rotates, and the sealant between the inner periphery of the cylinder 34 and the screw portion 36A on the outer periphery of the screw 36 is discharged from the nozzle 33, and the rotation amount of the motor 41 An amount of the sealing agent corresponding to the amount is discharged from the nozzle 33. [0024] For example, when the screw 36 rotates, a sealant corresponding to the pitch of the screw portion 36A is discharged from the nozzle 33. Since the discharge amount per unit time of the sealant from the nozzle 33 is proportional to the rotation speed of the motor 41 (rotation amount per unit time), the sealant from the nozzle 33 can be changed by changing the rotation speed of the motor 41. The amount of discharge per unit time can be changed.

 [0025] In the discharge pump 32, the screw 36 does not push out the sealing agent by the pressure gas as in the prior art, and the screw part 36A directly mechanically pushes out the liquid sealing agent. A proportional discharge rate is obtained.

 [0026] The moving devices 17 and 18 including the feed tables 13 and 15 and the feeding mechanisms 14 and 16 in the X-axis direction and the Y-axis direction of the stage 30 and the moving device 19 including the two heads 22 and the feeding mechanism 23 The nozzle 33 of the pump 32 and the substrate 31 on the stage 30 are relatively moved in parallel along the substrate 31 surface.

 [0027] The paste coating apparatus 10 includes a control device (not shown), and the control device has a relative movement speed in the direction along the substrate surface between the nozzle 33 and the substrate 31, that is, a relative movement speed in the X-axis direction, a Y-axis The rotation speed of the motor 41 of the discharge pump 32 is controlled according to the relative movement speed in the direction and the relative movement speed obtained by combining the relative movement speed in the X-axis direction and the relative movement speed in the Y-axis direction.

 Next, the operation of applying the sealing agent to the peripheral edge of the glass substrate 31 for the liquid crystal display panel held on the stage 30 by the coating apparatus 10 having the above configuration will be described with reference to FIGS. Will be described with reference to FIG. Note that here, since the two heads 22 draw the same coating pattern P in parallel, only the coating operation by one head 22 of the two heads 22 will be described for the sake of simplicity. To do.

 The coating apparatus 10 draws a rectangular coating pattern P by coating a sealing agent along the peripheral edge of the rectangular glass substrate 31 in a clockwise direction in FIG.

First, the control device moves the nozzle 33 directly above the application start point O. The gap between the nozzle 33 and the surface of the substrate 31 becomes a preset gap by feedback control based on the measured value of the distance measuring device while lowering the nozzle 33 by controlling the Z-axis moving device. To control. [0031] After that, the control device rotates the motor 24 of the X-axis direction moving device 17 composed of the feed table 13, and moves the substrate 31 to the right of the X-axis in FIG. . At the same time, the control device rotates the motor 41 of the discharge pump 32 in synchronization with the motor 24 of the moving device 17 in the X-axis direction (hereinafter described as moving the feed table 13 in the X-axis direction), and the nozzle 33 The sealant is discharged from.

 FIG. 4 shows the application position on the substrate in the process of reaching the application start point O force application end point F on the horizontal axis, and the rotational speed of the motor 41 of the discharge pump 32 on the vertical axis.

 [0033] At the application start point O, the motor 24 of the moving device 17 in the X-axis direction accelerates the stop state force to the rotational speed Vs set corresponding to the straight line portion S, so that the control device moves in the X-axis direction. The rotation of the motor 41 of the discharge pump 32 is accelerated from the stop state to the first rotation speed V 1 corresponding to the rotation speed Vs in synchronization with the change in the rotation speed of the motor 24 of the moving device 17.

 [0034] In the vicinity of the coating start point O (indicated by W1 in FIG. 4), the moving speed of the moving device 17 is lower than the moving speed of the linear portion S (shown in FIG. 4) of the coating pattern P. . In the low-speed movement area near the application start point O, the discharge amount per unit time of the sealant is made smaller than the discharge amount in the high-speed movement area corresponding to the straight line portion S, so that the application amount per unit length is high. It should be the same as the application amount in the moving area. As a result, the application amount is prevented from increasing near the application start point O, and the expansion of the line width and thickness of the application pattern is prevented.

 [0035] Next, when approaching the left front corner C1, the control device sets the motor 24 of the X-axis direction moving device 17 corresponding to the low speed moving area near corner C1 (indicated by W2 in FIG. 4). Decelerate to the specified rotation speed Vw. Synchronizing with the deceleration of the motor 24 of the movement device 17 in the X-axis, the control device rotates the rotation of the motor 41 of the discharge pump 32 from the first rotation speed VI to the second rotation speed V2 corresponding to the rotation speed Vw. To slow down.

[0036] Next, when reaching the left front corner C1, the control device decelerates and stops the motor 24 of the moving device 17 in the X-axis direction. The controller starts the rotation of the motor 25 of the moving device 18 in the Y-axis direction simultaneously with the start of the deceleration, and the relative movement of the substrate 31 and the nozzle 33 in the direction along the substrate 31 surface during the drawing of the corner C1 portion. The rotation speed is controlled so that the speed is constant. As shown in FIG. 4, the control device operates during this period with the motor 41 of the discharge pump 32. Is maintained at the second rotation speed V2.

[0037] In the vicinity of this corner C1 (indicated by W2 in FIG. 4), the moving speed of the moving device 17 is lower than the moving speed of the linear portion S of the coating pattern P. In the low-speed moving area near W1 at corner C1, the amount of sealant dispensed per unit time is less than the amount discharged in the high-speed moving area, and the amount applied per unit length is the same as the amount applied in the high-speed moving area. To be.

 [0038] As a result, the application amount is prevented from increasing in the vicinity of corner C1, W2, and the expansion of the line width and thickness of the application pattern is prevented. In addition, since the relative movement speed between the substrate 31 and the nozzle 33 is lower than the movement speed of the linear part S near the corner C1, the head 22 caused by the acceleration / deceleration of the moving devices 17 and 18 at the corner C1. By preventing vertical vibrations, it is possible to prevent the occurrence of pattern breakage and variation in coating amount at corner C1 and near W2.

 [0039] Next, in the same manner as the left front corner C1, the left end corner C2, the right rear corner C3, and the right front corner C4 are reached before the application end point F. In the low-speed moving area near corners C2, C3, and C4, the discharge rate per unit time is reduced so that the coating amount per unit length is the same as the high-speed moving area, as in the case of corner C1 above.

 [0040] In the vicinity of the application end point F, the control device gradually slows down the rotation of the motor 41 of the discharge pump 32 in synchronism with the deceleration of the motor 24 of the moving device 17 in the X-axis direction, and the sealing agent. Reduce the discharge amount. As a result, the application amount is prevented from increasing in the vicinity of the application end point F, and the expansion of the coating pattern in the line width direction and thickness is prevented.

 [0041] Next, the nozzle 33 is moved to the application start point O of the next pattern. When this pattern is the last pattern to be formed on the substrate 31, it is not necessary to move the application end point F force to the application start point O. Thus, one cycle of applying the sealing agent on the glass substrate 31 is completed.

[0042] When the sealant is applied to the substrate 31 with the rectangular application pattern P as described above, in the vicinity of the application start point O, during application of corners C1 to C4 (hereinafter referred to as corner C), and in the vicinity of the application end point F Then, since the relative moving speed of the nozzle 33 and the substrate 31 is slower than that of the straight line portion S, the rotational speed of the motor 41 is slowed down to reduce the discharge amount of the sealant from the nozzle 33. As a result, a coating pattern P having a uniform coating amount power can be drawn on the substrate 31. Further, as shown in FIG. 5, when there is a step or a recess G on the flat substrate 31 A due to the film thickness of the surface of the substrate 31 A, the configuration of the circuit, etc., the motor 41 for discharging the sealing agent from the nozzle 33 Increase the rotational speed and partially increase the amount of sealant applied from other parts I than the recesses G.

 [0044] When the sealant is applied to the substrate 31A with the rectangular coating pattern P so that the coating amount per unit length is constant, if there is a recess G on the surface of the substrate 31A, the recess G will The application height becomes low. In this case, the rotational speed of the motor 41 is increased so that the discharge amount per unit time of the sealing agent from the nozzle 33 is increased in the recess G. In this way, the height of the applied sealant (not the relative height of the surface force of the substrate 31A but the absolute height) is controlled to be constant.

 As a result, a coating pattern having a uniform height is drawn on the surface of the substrate A31, and when the two substrates 31A and 31B are bonded together, a gap H is generated between the substrates 31A and 31B. As a result, it is possible to prevent the liquid crystal sealed by the sealing agent from leaking between the two substrates 31A and 31B that are bonded together, or the air from entering the region surrounded by the sealing agent. Thereby, the quality of the manufactured liquid crystal display panel can be improved.

 [0046] Although the example in which the concave portion is formed on the surface of the substrate 31A has been described, even when the convex portion is formed, the discharge amount of the sealing agent from the nozzle 33 is reduced at the position corresponding to the convex portion. It is possible to cope with this by reducing the rotation speed of the motor 41.

 [0047] Further, the position of the concave portion or the convex portion formed on the surface of the substrate 31A can be obtained by using design data of the substrate 31A or by measuring height data of the surface of the substrate 31A in advance. .

 [0048] According to the present embodiment, the following operational effects are obtained.

 [0049] (a) The discharge pump 32 mechanically pushes out an amount (volume) of the sealant proportional to the amount of rotation of the motor 41 by rotating the screw 36 with the motor 41. Even if the viscosity of the agent changes or the remaining amount of the sealant in the cylinder 34 of the discharge pump 32 decreases, the rotational speed of the motor 41 of the discharge pump 32 is kept constant so that the sealant from the nozzle 33 The discharge amount per unit time can be kept constant.

[0050] Further, in the case of discharge by gas pressure, the gap between the nozzle 33 and the substrate 31 varies. And the discharge resistance of the sealant from the nozzle 33 fluctuates, and this influences the discharge amount of the sealant.

 [0051] While applying the force, according to the coating apparatus 10 or the coating method of the present embodiment, the amount of the sealing agent extruded by the mechanical extrusion by the screw portion 36A of the screw 36 accompanying the rotation of the screw 36 is set to the nozzle. Since it is discharged from the nozzle 33, the amount of the sealing agent pushed out by the threaded portion 36A can be discharged from the nozzle 33, and the discharge amount of the sealing agent at the nozzle 33 force of the discharge pump 32 is less susceptible to fluctuations in the gap. Always mechanically extrude a certain amount of sealant.

 As a result, the sealing agent can be applied on the substrate 31 in a uniform application amount, and the application accuracy of the sealing agent to the substrate 31 can be improved. Therefore, it is possible to manufacture a high quality liquid crystal display panel in which liquid crystal leakage and air intrusion are prevented.

 [0053] Further, as described above, control (gap control) for maintaining a constant gap between the nozzle 33 and the substrate 31, which is essential when the nozzle force is also discharged by the gas pressure, is unnecessary, or the frequency is increased. It is possible to reduce the number and simplify the control. This also eliminates or reduces the time required for the gap control process, thereby reducing the time required for applying the sealant and improving the efficiency.

 [0054] (b) When the sealing agent is applied to the substrate 31 with the rectangular application pattern P, the nozzle 33 and the base are compared in the vicinity of the application start point O, in the vicinity of the corner C, and in the application end point F as compared with the straight line portion S. Since the relative movement speed with respect to the plate 31 becomes slow, the rotational speed of the motor 41 of the discharge pump 32 is slowed down, and the discharge amount of the sealant from the nozzle 33 per unit time is reduced.

 At this time, the discharge amount of the sealant from the nozzle 33 per unit time is controlled with good responsiveness by mechanical extrusion by the rotation of the screw 36. As a result, a coating pattern having a uniform coating amount force can be drawn on the substrate 31.

 [0056] (c) When the relative movement speed between the nozzle 33 of the discharge pump 32 and the substrate 31 is reduced near the application end point F during application near the application start point O and corner C, the substrate 31 moving device 1 Decreased by synchronizing the rotation speed of the motor 41 of the screw 36 of the discharge pump 32 with the rotation speed of the motor 24, 25 of the motors 7 and 18.

[0057] As a result, as before, during application near the coating start point O and corner C, and at the end of coating It is possible to prevent the application amount of the sealant from increasing near the point F, and to draw an application pattern on the substrate 31 with a uniform application amount.

 (D) By synchronously controlling the rotational speeds of the motor 24 of the X-axis moving device 17 or the motor 25 of the Y-axis direction moving device 18 and the motor 41 of the discharge pump 32, the coating start point O The timing at which a single agent is discharged from the nozzle 33 and the timing at which the stage 30 or the head 22 starts to move can be made the same each time as set.

 Similarly, at the application end point F, the timing at which the stage 30 or the head 22 stops and the timing at which the sealing agent is stopped from being discharged from the nozzle 33 can be made the same each time. As a result, it is possible to draw with good reproducibility as the shapes of the sealing agent application start point O and the application end point F are set.

 [0060] (e) Since the sealing agent is mechanically pushed out from the nozzle 33 by the rotation of the screw 36, the amount of discharge of the sealing agent per unit time can be changed by changing the rotation speed of the motor 41 that rotates the screw 36. Can be increased or decreased with good responsiveness.

 Therefore, when the substrate 31 has a step or a recess G due to the film thickness of the surface of the substrate 31 or a circuit configuration, the rotational speed of the motor 41 that discharges the sealant from the nozzle 33 according to the step or the recess G. By changing the gas pressure applied to the cylinder 34 by changing the gas pressure applied to the cylinder 34, it is easier to change the amount of the sealant applied. The coating pattern P can be drawn with good reproducibility by the coating amount.

 (0062) (D) The pressure gas is supplied into the pressure gas chamber 45 of the storage container 40 while the screw 36 is rotating, and the supply of the pressure gas is stopped at the timing when the rotation of the screw 36 is stopped. Since the gas presses the sealant in the storage container 40 toward the opening 43 while the screw 36 is rotating, the gas is surely inserted into the cylinder 34 without causing insufficient suction of the sealant at the opening 43 part. A sealing agent can be supplied.

[0063] As a result, the sealing agent can be discharged stably from the nozzle cover, preventing problems such as variations in the amount of the sealing agent applied and disconnection of the drawn sealing agent application pattern P. can do. This is particularly effective when the viscosity of the sealant is high or when the rotational speed of the screw 36 is high. [0064] Further, by stopping the supply of the pressure gas at the timing of stopping the rotation of the screw 36, the application of the pressing force to the sealant by the pressure gas is stopped while the screw 36 is stopped. Prevents the sealant from leaking out of the nozzle 33

[0065] As a result, at the next application of the sealant onto the substrate 31, the sealant that leaks from the nozzle 33 and accumulates at the tip of the nozzle 33 adheres to the application start position on the substrate 31, and that portion. It is possible to prevent the application amount from becoming excessive in minutes. This also makes it possible to apply the sealing agent with a uniform application amount and high quality.

 As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration of the present invention is not limited to these embodiments, and design changes and the like within a scope not departing from the gist of the present invention are possible. Any case is included in the present invention. For example, in the embodiment, a force in which the rotational speed of the motor 41 of the discharge pump 32 is controlled according to the relative moving speed between the nozzle 33 and the substrate 31 is discharged so that the coating amount per unit length of the sealant is constant. It is possible to control the rotation speed of the motor 41 of the pump 32.

 Further, although an example in which the relative movement speed between the substrate 31 and the nozzle 33 is decelerated in the vicinity of the corner C has been described, the relative movement speed of the straight line portion S may be left as it is. In this case, even if the head 22 oscillates vertically due to acceleration / deceleration of the moving devices 17 and 18 at the corner C, and the discharge resistance of the sealant from the nozzle 33 fluctuates, the screw 36 Since the sealing agent extruded by the mechanical extruding by the thread portion 36A is discharged from the nozzle 33, it is possible to prevent the paste discharge amount from the nozzle from changing.

 [0068] Therefore, the paste can be applied to the substrate with the required application amount, and even in the vicinity of the corner C, the paste can be applied linearly with a uniform application amount, with high accuracy. A coating pattern can be formed.

 [0069] The force gap control described in the example of performing the gap control may be omitted. In this case, the gap control may not be performed at all, or the gap control may be performed only when the nozzle 33 is positioned at the coating start point O, and the gap control may be omitted during pattern drawing.

[0070] Further, as shown in FIG. 2, the screw 36 is provided with a nozzle 33 having a cylinder 34 at its lower end. The example has been described so as to reach the bottom (tip) formed, but it may be arranged so as to provide a space 47 between its lower end and the bottom of the cylinder 34 as shown in FIG.

 That is, the screw 48 is provided in the cylinder 34, the upper end portion is connected to the rotating shaft of the motor 41 via the connecting member 35, and the lower end portion is a free end. The screw 48 has a larger gap between its free end and the bottom of the cylinder 34 where the nozzle 33 is provided, than the distance between the free end of the screw 36 and the cylinder 34 shown in FIG. In the meantime, the sealant can be stored.

[0072] In addition, the screw portion 36A of the screw 34 may be a plurality of strips having a force of two or more as described in the example of one strip. As described above, when a plurality of thread portions 36A having the pitch P are provided (n-row), the lead L is L = nP. In the case of the screw 36 having the _n- thread thread 36A at the same pitch P as the screw 36 having the single thread 36A, in order to obtain the same discharge amount as that of the screw 36 having the single thread 36A. The number of rotations of the motor 41 required for this is 1 / n.

 [0073] For this reason, the rotational speed of the motor 41 that drives the screw 36 to rotate is only lZn. It is possible to suppress the curing and deterioration of the agent due to heat generation, and it is possible to prevent the loss caused by discarding the expensive sealant.

 Industrial applicability

[0074] According to the present invention, the paste can be applied to a target location on the substrate in a necessary amount, and the accuracy of applying the paste to the substrate can be further improved. Therefore, when the two substrates are glass substrates for manufacturing a liquid crystal display panel and the liquid material is liquid crystal, the liquid crystal display panel is manufactured with good quality in which liquid crystal leakage and air intrusion are prevented. It can be done.

Claims

The scope of the claims  [1] In a paste application apparatus that discharges a paste for sealing a liquid substance between two substrates from a nozzle and applies the paste to at least one substrate.  A pump unit having a cylinder having a nozzle, a screw that is rotatably provided in the cylinder, and discharges an amount of paste from the nozzle according to the rotation amount; and a motor that rotates the screw;  A paste coating apparatus comprising: a moving device that relatively moves the nozzle and the substrate along the substrate surface; a motor of the pump means and a control device that controls the moving device.  [2] The paste application apparatus according to [1], wherein the control device controls a motor of the pump means in accordance with a relative movement speed between the nozzle and the substrate. [3] The paste applicator according to claim 2, wherein the control device controls the motor of the pump means so that the amount of the paste applied to the substrate per unit length is constant.  [4] The control device controls the motor of the pump means so as to vary the coating amount per unit length of the paste on the substrate based on the relative position information between the nozzle and the substrate. The paste application apparatus according to claim 1. [5] The control device may be configured so that the coating amount per unit length in the concave portion is larger than the coating amount per unit length in other portions other than the concave portion on the substrate having the concave portion. 5. The paste application device according to claim 4, which controls a motor of the pump means. [6] The cylinder has the nozzle at the tip thereof,  2. The screw according to claim 1, wherein an end of the screw opposite to a connection end with the motor is opposed to the tip, and a predetermined interval is provided between the end and the tip. The paste applicator. 7. The paced coating apparatus according to claim 1, wherein the two substrates are glass substrates for manufacturing a liquid crystal display panel, and the liquid substance is a liquid crystal. [8] A storage container connected to the cylinder and storing the paste; A gas pressure source for supplying gas pressure into the storage container; The gas pressure source is configured to supply pressure gas into the storage container when the screw rotates, and to stop supplying pressure gas when the screw stops. The paste application apparatus according to claim 1. [9] The paste application device according to [1], wherein the screw has a plurality of thread portions.  [10] In a paste application method in which a paste for sealing a liquid substance between two substrates is ejected from a nozzle, and the paste is applied to at least one substrate.  When the paste is applied to the substrate by discharging the paste from the nozzle by a pump unit that discharges an amount of paste corresponding to the amount of rotation of the screw from the nozzle, the paste is applied to the substrate at a predetermined application amount. A paste application method for controlling the rotation of the screw so that the paste is applied.  11. The paste application method according to claim 10, wherein rotation of the screw is controlled according to a relative moving speed between the nozzle and the substrate. 12. The paced coating method according to claim 11, wherein the rotation of the screw is controlled so that a coating amount per unit length of the paste on the substrate is constant. [13] The rotation of the screw according to claim 10, wherein the rotation of the screw is controlled so as to vary the amount of application per unit length of the paste with respect to the substrate based on the relative position information between the nozzle and the substrate. Paste application method. [14] The rotation of the screw is controlled so that the coating amount per unit length in the concave portion is larger than the coating amount per unit length in other portions other than the concave portion on the substrate having the concave portion. The paste application method according to claim 13.