KR101735893B1 - Electrostatic application method and electrostatic application apparatus - Google Patents

Abstract

An object of the present invention is to realize uniform application of a pattern width with high edge linearity.
In this electrostatic application method, a potential difference is applied to form a liquid plumb portion extending toward the object to be coated at the tip of the nozzle, and the tip end of the needle disposed in the nozzle is projected to the liquid plumb portion, And the liquid contained in the nozzle is applied to the object to be coated.

Description

TECHNICAL FIELD [0001] The present invention relates to an electrostatic coating method and an electrostatic coating apparatus,

TECHNICAL FIELD The present invention relates to an electrostatic coating method for forming a fine pattern on a base material by elongating various liquids from the tip of a nozzle by an electric force.

BACKGROUND ART Conventionally, as a method of forming fine droplets and applying a fine pattern onto a substrate, there is known a method using electrostatic suction as described in Patent Document 1, for example.

Fig. 12 shows the method of Patent Document 1. Fig.

This method is a method in which a nozzle 2 is disposed opposite to the surface of an object to be coated 4 and a pulse voltage is applied between the object 4 and the nozzle 2 from a power source 30, The liquid 1 of the droplet 31 is attracted toward the object 4 by the electrostatic force to drop the droplet 31 onto the object 4 to be coated.

Patent Document 2 is not applied to an object to be coated, but a method of discharging a minute droplet having a uniform particle diameter into a solution using a needle is also known. In Patent Document 2, the same electrostatic force as in Patent Document 1 is not used.

Patent Document 1: Japanese Patent Application Laid-Open No. 2001-038911 Patent Document 2: Japanese Patent Application Laid-Open No. 2006-320795

In the case where the solution attached to the tip of the needle is to be applied as an object to be coated using the technique of Patent Document 2, the following applies.

The needle 32 disposed in the nozzle 2 is lowered as shown in Fig. 13 (a) until the tip thereof protrudes from the nozzle tip 3, as shown in Fig. 13 (b). At this time, a small amount of the droplet 33 of the liquid 1 in the nozzle 2 is attached to the front end of the needle 32. Thereafter, as shown in Fig. 13 (c), the needle 32 descends until the droplet 33 attached to the tip contacts the object 4 to be coated. Thereby, the droplet 33 attached to the tip of the needle 32 can be applied to the object 4 to be coated.

However, in the conventional method shown in Fig. 12 and the method shown in Fig. 13, when a fine linear pattern is formed on the surface of the object to be coated 4 by coating, the linearity of the edge of the coating result is poor, There is a problem that this uniform application can not be realized.

The application state in this case is shown in Fig.

Fig. 14 (a) shows a state immediately after continuously applying small droplets. Fig. 14 (b) shows a state in which drying of the applied droplet is completed. Thus, leveling between neighboring droplets proceeds in the drying step after coating, but since traces left as droplets remain, it is difficult to obtain the linearity of the edges. This is because the ejected minute liquid has a large surface area, and drying is promoted before it reaches the object 4 after it is discharged from the nozzle 2 and reaches the object 4. This is because leveling after reaching the object 4 becomes difficult.

From this, it is considered that, in order to realize coating with a high linearity of the edge and a uniform pattern width, it is preferable not to attach the droplet, but to continuously apply the droplet without cutting off the droplet.

15, the liquid holding portion 34 is formed at the tip of the nozzle 2, and the liquid 1 is continuously applied to the surface of the object 4 to be coated However, in the case of continuous application by the liquid fastening portion 34, since it takes time to form an abutment end which involves the elongation and contraction of the liquid fastening portion 34 by the electrostatic force, There is a problem that the application state tends to be disturbed.

Figs. 16 (a) to 16 (d) show the formation state of the liquid retaining portion 34 at the beginning of the application when the liquid 1 is continuously applied by the liquid retaining portion.

16 (a) shows a state before voltage application to the nozzle 2 in which the liquid 1 is placed.

Next, when a voltage is applied between the nozzle 2 and the object 4 to be coated, as shown in Figs. 16B and 16C, the liquid holding portion 34 is extended toward the object 4 due to the electrostatic force, 16 (c), the liquid immersion part 34 finally reaches the object 4 to be coated as shown in Fig. 16 (d) through the unstable liquid immersion part 34 state before reaching the object 4 .

16 (c), it takes time to shift from the unstable state in Fig. 16 (c) to the stable state in Fig. 16 (d), so that the relative movement of the nozzle 2 for application and the object 4 to be coated And the position at which the liquid holding portion 34 reaches the object 4 may be different from the target. As a result, as shown in Fig. 17 (a), a necessary amount of the liquid 1 is applied at the beginning of coating and a thick liquid portion 35 is formed on the line width, or conversely, There is a problem that the application amount of the liquid 1 is insufficient to cause the broken portion 36 as shown in Fig.

18 (a) to 18 (d) show a contracted state of the liquid holding portion 34 at the end of coating.

18 (a)) before the voltage application to the nozzle 2 containing the liquid 1 (Fig. 18 (a)), 18 (c) and (d), finally under the state of being unstably held without being separated from the object 4 to be coated due to the influence of electric charges.

In this suction by the electrostatic force, since the unstable state of Fig. 18 (b) continues even after the application of the voltage is stopped, the relative movement of the nozzle 2 and the object 4 for stopping the application is stopped The timing control becomes very difficult and the position where the liquid holding portion 34 is separated from the object 4 to be coated is different from the target. As a result, as shown in Fig. 19 (a), more liquid than necessary is applied to the end of coating, resulting in a thick liquid portion 35 in the line width, or conversely, There is a problem that the cut portion 36 is formed due to a shortage of the application amount of the substrate 1.

An object of the present invention is to provide an electrostatic coating method which does not require time for forming an abutment edge, and which is free from confusion of shape, has high edge linearity, and achieves uniform application of a pattern width.

An electrostatic coating method of the present invention is a method of electrostatic coating a liquid containing a liquid, which is arranged so that the nozzle tip of a nozzle is opposed to an object to be coated and a potential difference is applied between the liquid and the object to be coated, And the distal end of the needle disposed in the nozzle is protruded toward the liquid droplet so that the tip of the liquid droplet is brought into contact with the object to be coated.

An electrostatic applicator according to the present invention is an electrostatic applicator for applying a potential difference between a liquid in a nozzle and an object to be coated to draw out the liquid from the nozzle and applying the electric potential to the object to be coated, A needle driving part for vertically driving the needle; and a control part for controlling the power source part to form the liquid droplet extending toward the object to be coated on the nozzle tip at the time of application, And a control section for driving the needle driving section so as to project the tip of the needle toward the liquid droplet so as to bring the leading end of the liquid droplet into contact with the object to be coated.

According to the electrostatic application method of the present invention, a potential difference is applied to form a liquid droplet extending toward the object to be coated at the tip of the nozzle, and the tip of the needle disposed in the nozzle is protruded toward the liquid droplet, It is possible to increase the responsiveness of the liquid droplet at the tip of the nozzle, thereby preventing disturbance at the end of the coating and shortening the tact time. Further, since the liquid can be continuously applied, a pattern with high linearity can be precisely formed.

1 is a schematic view of an electrostatic coating device in an embodiment of the present invention,
Figs. 2 (a) to 2 (c) are a coating flow chart at the coating start point in the above embodiment,
3 (a) to 3 (c) are a coating flow chart at the coating end in the above embodiment,
4 is an enlarged cross-sectional view of the nozzle tip of Condition 1 of the electrostatic coating apparatus in the above embodiment,
5 is an enlarged view showing the contact angles? 1 to? 3 of the needles in the condition 1,
Fig. 6 is an explanatory diagram of the application results of the conditions 1 to 8 of the present invention
7 is an enlarged cross-sectional view of the nozzle tip of Condition 3 of the electrostatic coating apparatus in the above embodiment,
8 is an enlarged view showing the contact angles? 4 and? 5 of the needles in the condition 3,
Fig. 9 is an enlarged cross-sectional view of the nozzle tip of Condition 5 of the electrostatic coating device in the embodiment,
10 is an enlarged cross-sectional view of the nozzle tip of Condition 7 of the electrostatic coating device in the above embodiment,
11 is an enlarged view showing the contact angles? 6 and? 7 of the needle in condition 7,
12 is an explanatory diagram of Patent Document 1 by electrostatic suction by pulse voltage,
Figs. 13 (a) to 13 (c) are a coating flow chart when referring to Patent Document 2,
Figs. 14 (a) and 14 (b) are explanatory views of problems in the case of applying the coating flow of Fig. 13,
Fig. 15 is a diagram of a continuous application state by a liquid gauge stretched by an electrostatic force according to Patent Document 1,
16 (a) to 16 (d) are views showing a state in which the liquid is formed in the beginning of application by the liquid medium in Patent Document 1,
17 (a) and 17 (b) are plan views of coating defects at the coating start time according to Patent Document 1,
Figs. 18 (a) to 18 (d) are diagrams of a state in which the liquid is formed in the coating end according to Patent Document 1,
19 (a) and 19 (b) are plan views of coating defects at the coating end according to Patent Document 1. Fig.

Hereinafter, the electrostatic application method of the present invention will be described based on the electrostatic application device of the embodiment.

1 to 3 show an electrostatic coating apparatus for realizing the electrostatic coating method of the present invention.

In Fig. 1, the electrostatic coating apparatus is constructed as follows.

The nozzle 2 in which the liquid 1 is placed is arranged so that the tip end 3 of the nozzle faces the object 4 to be coated. A voltage is applied between the liquid 1 and the object 4 by the power supply unit 5. Inside the nozzle 2, a vertically movable needle 6 is disposed. The liquid (1) is supplied from the liquid supply part (7) to the inside of the nozzle (2).

In the case of using the nozzle 2 formed of an insulating material, since the voltage can not be applied through the nozzle 2, the electrode plate 8 contacting the liquid 1 inside the nozzle 2 And a voltage is applied from the power supply unit 5 through the electrode plate 8. [ When the nozzle 2 is formed of a conductive material, a voltage can be applied via the nozzle 2, so that the electrode plate 8 may be omitted.

The nozzle 2 is held by the nozzle driving unit 9 and movement control of the vertical position with respect to the object 4 is performed. The needle 6 is held by the needle driver 10 and its vertical position is controlled.

The stage 11 is positionally controlled by a stage driving unit 12 that moves the object 4 in a horizontal direction at the time of application while holding and holding the object 4 to be coated.

A voltage is applied between the object 4 to be coated and the liquid 1 contained in the nozzle 2 by the power source unit 5. The nozzle driving unit 9, the needle driving unit 10, and the stage driving unit 12 are controlled by the control unit 13.

Although the stage driving unit 12 is provided to relatively move the nozzle 2 and the object 4 in the horizontal direction at the time of coating, the stage driving unit 12 may be provided in the nozzle horizontal driving unit (not shown) for moving the nozzle 2 in the horizontal direction And the stage driving unit 12 may be provided to relatively move the nozzle 2 and the object 4 in the horizontal direction at the time of application.

Figs. 2 (a) to 2 (c) show a coating flow chart at the coating start end. FIG. 2 (a) shows the state before the application of voltage at the application start time, FIG. 2 (b) shows the state immediately after the application of voltage to the application start time, and FIG. 2 (c) shows the time at which the liquid reaches the application object. Fig. 3 (a) shows the normal coating at the coating end, Fig. 3 (b) shows the needle moving up at the coating end, and Fig. 3 (c) shows the needle moving end at the coating end.

This is explained based on the coating flow.

2 (a), the object 4 to be coated is placed on the stage 11, and the nozzle 2 is aligned with the application start position. At this time, the tip of the needle 6 is positioned by the needle driver 10 such that the tip of the needle 6 is located inside the nozzle 2 rather than the tip 3 of the nozzle.

Next, the height of the nozzle 2 is controlled by the nozzle driving unit 9 so that the gap between the nozzle tip 3 and the object 4 becomes a desired distance.

2 (b) and 2 (c), a voltage is applied between the liquid 1 and the object 4 by the power supply unit 5, and the needle 6 is moved to the needle driving unit 10 To the object 4 side until the tip reaches the desired position toward the object 4 side of the object 4 than the tip end 3 of the nozzle.

This causes the liquid 1 to be attracted toward the object 4 by the electrostatic force and the center portion of the liquid holding portion 14 at the nozzle tip 3 It is possible to selectively extend to the side of the object 4 and the time during which the object to be coated 4 reaches an unstable state during the process of extending the liquid adhesive portion 14 toward the object 4 can be significantly shortened .

As a result, timing control for starting the relative movement of the nozzle 2 and the object 4 to be coated can be facilitated, and the position at which the liquid holding portion 14 reaches the object 4 to be coated, It becomes possible. Thereby, even at the initial stage of coating, it is possible to obtain an effect that precise application can be realized without causing the line width to be thick or broken. Further, since the time required for coating at the starting end can be shortened, the effect of shortening the production tact can be obtained.

Thereafter, the nozzle 2 and the object 4 to be coated are relatively moved in the horizontal direction at a desired timing and applied after the finely stretched liquid fastener 14 reaches the object 4 to be coated.

The timing of starting the relative movement between the nozzle 2 and the object 4 in this case is confirmed by experiments in the prior art, so that stable application can be easily reproduced. This is because the central portion of the liquid holding portion 14 at the nozzle tip 3 is selectively extended toward the object 4 to be coated by the descent of the needle 6 so that the liquid holding portion 14 contacts the object 4 to be coated, It is possible to remarkably shorten the time in which the object 4 is in an unstable state before it reaches the object 4. [

3 (b) and 3 (c), at the application terminating position, the liquid 1 and the object 1 to be coated 4), and the needle 6 is raised to the nozzle 2 side until the tip reaches the desired position inside the nozzle tip 3, as shown in FIG.

As the needle 6 is lifted up like this, it is possible to selectively return the central portion of the liquid holding portion 14 to the nozzle 2 side at the nozzle tip end 3, It is possible to drastically shorten the period of time in which the object 14 remains unstable without being separated from the object 4 due to the influence of the residual charge retained by the mother portion 14. [ As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG.

Thereby, an effect of precisely coating can be realized even at the coating end, without causing the thickness of the line width or the stitching portion. In addition, since the time required for coating at the end can be shortened, the effect of shortening the production tact can be obtained.

The timing of stopping the power supply unit 5 and raising the needle 6 in this case is confirmed by experiments in the prior art, so that stable application can be easily reproduced. This is because it is possible to selectively return the center portion of the liquid holding portion 14 at the nozzle tip 3 to the nozzle 2 side by the rise of the needle 6, It is possible to drastically shorten the period of time in which the object 14 remains unstable without being separated from the object 4 due to the influence of the residual charge retained by the mother 14.

As described above, according to the present invention, it is possible to increase the responsiveness of the liquid droplet at the tip of the nozzle by vertically moving the needle 6, to prevent disturbance at the end of the application, Shortening can be realized. Further, since the liquid can be continuously applied, a pattern with high linearity can be precisely formed.

The above electrostatic coating apparatus will be described in detail based on conditions 1 to 8.

- Condition 1-

A fine linear pattern was applied using the electrostatic coating apparatus shown in Fig. The details of condition 1 are as follows.

Here, the nozzle 2 is made of glass, and as shown in Fig. 4, a tip inner diameter 15 of 200 mu m is used. For the liquid 1, a nano-Ag ink 16 having a center particle diameter of 200 nm was used. The solid concentration of the nano-Ag ink was 80 wt% and the viscosity of the ink was 1500 mPa · s. The needle 6 was made of tungsten, and a circular rod whose diameter 17 was constant at 50 占 퐉 was used. As the object 4 to be coated, a glass substrate having a thickness of 1.7 mm was used. The distance between the nozzle tip face 18 and the object 4 was set to 400 mu m. As shown in Fig. 5, the contact angle [theta] 1 of the nano Ag ink 16 in the nozzle tip end face 18 is 20 [deg.], The contact angle [theta] 2 of the nano Ag ink 16 in the needle side face 16 is 15 [ The contact angle? 3 of the nano Ag ink 16 at the tip 19 was set at 15 degrees.

The needle tip end face 19 is held at a position of 500 mu m from the nozzle tip end face 18 toward the inside of the nozzle 2 at the non-sparking position, and the needle tip end face 19 is held from the nozzle tip end face 18 toward the coating target object 4 The needle tip end face 19 was held at a position of 200 mu m toward the needle tip end face. The gap 21 between the inner wall of the nozzle 2 and the needle side 20 in the nozzle tip end face 18 is 75 m and is larger than 50 m which is the diameter 17 of the needle 6 Respectively. Further, the moving speed of the needle 6 was 15 mm / s, and the power supply unit 5 applied a DC voltage of 1.5 kV. At this time, the side of the nozzle 2 was set to +.

At the beginning of the application, a voltage was applied and the falling of the needle 6 was started. After 100 ms from the application of the voltage, the relative movement (speed 50 mm / s) between the nozzle 2 and the object 4 was started. In the coating end, the voltage application was stopped 100 ms before reaching the coating end position, and the needle 6 was started to rise. The rising speed at that time was set at 15 mm / s.

Thus, 30 coatings having a line width of 8 탆, a coating thickness of 0.5 탆 and a coating length of 100 mm were formed, and the coating start end and the coating ending end in the range of 20 mm from the coating end were evaluated. The results are shown in Fig.

The evaluation indexes of the line widths at the starting and ending points in Fig. 6 were evaluated as " o " when all the samples were contained in the range of 8 mu m +/- 3%, and " x " With respect to the broken portion, it was evaluated as & cir & if there was no broken portion in all samples, and & cir & With regard to the coating position accuracy at the end of the stage, the amount of displacement of the position with respect to the target position is? When the sample is within 100 占 퐉, and when the position is displaced beyond 100 占 퐉 at one position, the result is?. About line width of start and end,

If all the samples are included in the range of 8 mu m +/- 2.8%

If all the samples are included in the range of 8 μm ± 2.5%

If all the samples are in the range of 8 mu m + - 2.3%

If all the samples are included in the range of 8 mu m +/- 2.0%

Respectively. The results of evaluating the conditions 2 to 8 and Comparative Example 1 described below on the same basis as the condition 1 are shown in Fig.

- Comparative Example 1 -

As comparative example 1, it was applied by a method accompanied by elongation and contraction of the liquid vowel part only by the electrostatic force according to the conventional method shown in Fig.

The nozzle 2 of Comparative Example 1 was made of glass and had an inner diameter of the nozzle tip of 200 mu m. As the liquid 1, a nano Ag ink having a center particle diameter of 200 nm was used. The solid concentration of the nano-Ag ink was 80 wt% and the viscosity of the ink was 1500 mPa · s. The object 4 to be coated was a glass substrate having a thickness of 1.7 mm. And the distance between the nozzle tip surface and the object 4 was set to 400 mu m. The contact angle &thetas; 1 of the nano Ag ink on the nozzle line section was set to 20 DEG. The power supply unit 5 applies a DC voltage of 1.5 kV (+ on the nozzle side). The relative movement (speed 50 mm / s) between the nozzle 2 and the object 4 was started 100 ms after the application of the voltage at the application start time. In the coating end, the voltage application was stopped 100 ms before reaching the coating end position.

In the electrostatic application of Comparative Example 1 according to the conventional method, the liquid adhesion portion 14 is stretched toward the object 4 by the electrostatic force immediately after the voltage is applied and the liquid immersion portion (not shown) before reaching the object 4 14 finally reach the object 4 to be coated through the unstable state. Since the conventional method of sucking by electrostatic force requires a long time from the unstable state to the stable state before reaching the object 4 of the liquid holding portion 14, the nozzle 2 for application and the object 4 to be coated, And the position at which the liquid holding portion 14 reaches the object to be coated 4 is different from the target. As a result, there has been a problem that the application amount is applied to the application beginning amount more or the line width becomes thick, or conversely, the coating amount is shortened and the application amount is shortened.

In the coating end, even after the voltage application is stopped, the liquid remains in unstable state without being separated from the object 4 due to the influence of the residual charge retained by the liquid holding portion 14, The liquid condensate 14 was separated. As described above, in the conventional suction by the electrostatic force, since the unstable state continues after stopping the voltage application, it is very difficult to control the timing of stopping relative movement of the nozzle 2 and the object 4 to finish the application The position where the liquid holding portion 14 is separated from the object to be coated 4 is different from the target. As a result, an excessive amount of coating is applied to the coating end, resulting in a problem that the line width becomes thick, or conversely, the coating amount is shortened.

On the other hand, under Condition 1, as the needle 6 descends at the application start, the central portion of the liquid holding portion 14 at the tip of the nozzle can be selectively extended toward the object 4 to be coated, It is possible to remarkably shorten the time in which the untreated state before reaching the object 4 in the course of the pregnant women 14 extending toward the object 4 to be coated. As a result, timing control for starting the relative movement of the nozzle 2 and the object 4 to be coated can be facilitated, and the position at which the liquid holding portion 14 reaches the object 4 to be coated, It becomes possible. Thus, precise application can be realized even at the beginning of coating, without causing the line width to be thick or broken.

Further, since it is possible to shorten the time required for coating at the starting end, shortening of the production tact can be realized.

Since the contact angle? 1 of the nano Ag ink 16 in the nozzle tip end face 18 is larger than the contact angle? 2 in the needle side face 20 and the contact angle? 3 in the needle tip end face 19, It is possible to prevent the liquid holding portion 14 drawn out from the nozzle 2 from getting wet by the nozzle front end face 18 due to the descent of the liquid holding portion 6 and to prevent the liquid holding portion 14 . As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

As the needle 6 rises at the end of coating, it is possible to selectively return the central portion of the liquid holding portion 14 at the nozzle tip to the nozzle side, so that even at the end of the voltage application, 14 can be kept unstable without being separated from the object 4 due to the influence of the residual charge. As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

- Condition 2 -

In condition 1, θ1 = 20 °, θ2 = 15 °, and θ3 = 15 °. In this condition 2, θ3 = 10 ° is changed. Fig. 6 shows the evaluation results of the coating step state using the same index as in condition 1.

In the condition 2, since the contact angle of the needle tip end face 19 is the smallest, the velocity of the elongation and contraction of the liquid needle portion 14 in the needle tip end face 19 is the same as in the case of Condition 1 Speed operation can be realized by comparison, and stable continuous coating can be realized without the liquid holding portion 14 being disconnected.

In addition, since the needle contact surface 19 has the smallest contact angle, it is possible to improve the responsiveness in separating the liquid holding portion 14 from the needle tip end surface 19 as compared with the condition 1 at the coating end . As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

- Condition 3 -

In the condition 2, the portion of the needle 6 positioned inside the nozzle 2 protrudes to the outside of the nozzle 2 as shown in Fig. 4 and the portion protruding to the outside of the nano Ag ink 16 of the needle side 20 7 and 8, in this condition 3, the contact angle of the side surface of the needle 6 that is projected toward the object 4 to be coated is smaller than the contact angle of the nozzle tip surface 18 And has two different regions 22 and 23. The contact angle? 4 of the area 22 on the nozzle side is 15 degrees and the contact angle? 5 of the area 23 on the tip side of the needle 6 is 13 degrees. The other conditions were the same as those of condition 2. Fig. 6 shows the results of evaluation of the coating step state using the same index as in condition 1.

In this condition 3, since the needle contact surface 19 has the smallest contact angle, it is possible to improve the effect of holding the liquid holding member 14 in the needle tip end surface 19 as compared with the condition 1. The contact angle? 4 of the area 22 on the nozzle side is smaller than the contact angle? 4 on the tip side region 23 of the needle 6 on the side of the needle 6 that is closer to the object 4 than the tip of the nozzle line 18 ), It is possible to improve the effect of holding the nano Ag ink 16 at the tip of the nozzle as compared with the case of the condition 2. As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

In addition, since the needle contact surface 19 has the smallest contact angle, the effect of holding the liquid holding portion 14 in the needle tip end surface 19 is improved as compared with the condition 1, 14 are separated from each other.

The contact angle? 4 of the nozzle-side region 22 in the nozzle side region 22 of the needle side face portion that is projected toward the object 4 side of the coating object 4 at the time of application is smaller than the contact angle? , It is possible to improve the effect of holding the nano Ag ink 16 in the needle tip end face 19 as compared with the case of the condition 2. As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. As a result, even at the coating end, it was possible to realize precise coating without causing line width or breakage. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

In this condition 3, θ2 = θ4, but by making θ2> θ4, stable liquid supply to the liquid holding portion 14 formed at the tip of the nozzle from inside the nozzle becomes possible as compared with the case of θ2 = θ4. As a result, stable continuous coating can be realized without cutting off the liquid holding portion 14.

- Condition 4 -

In condition 3, the needle 6 was set at? 5 =? 3 in the condition 4, while? 4 = 15,? 5 = 13, and? The other conditions were the same as in condition 3.

The contact angle? 4 of the nozzle side region 22 of the needle side face portion that protrudes toward the object 4 toward the object 4 side relative to the nozzle face face 18 at the time of liquid application is 15 degrees and the area 23 at the tip side of the needle 6, The contact angle &thetas; 5 was 10 DEG smaller than the contact angle &thetas; 4. Fig. 6 shows the evaluation results of the coating step state using the same index as in condition 1.

In the electrostatic application under Condition 4, since the needle contact surface 19 has the smallest contact angle, it is possible to improve the effect of holding the liquid holding portion 14 in the needle tip end surface 19 as compared with the condition 1. The contact angle? 5 of the tip end side region 23 of the needle side face portion that is projected toward the object 4 side of the nozzle tip face 18 at the time of application is made equal to the contact angle? 3 of the end face of the needle tip, The effect of holding the nano Ag ink 16 at the tip of the nozzle can be improved. As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

Since the needle contact surface 19 has the smallest contact angle at the coating end, the effect of holding the liquid holding portion 14 in the needle tip end surface 19 as compared with the condition 1 can be improved, It may lead to an improvement in the responsiveness in separating the stay 14. The contact angle? 5 of the tip end side region 23 of the needle side face portion that is projected toward the object 4 side of the nozzle line end face 15 at the time of application is made equal to the contact angle? 3 of the end face of the needle line, The effect of holding the nano Ag ink 16 at the tip of the nozzle can be improved. As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

- Condition 5 -

The needle 6 of each condition described above uses a circular rod whose diameter is constant up to the tip. In this condition 5, the tip of the needle 6 is formed in a thin tapered shape as shown in Fig. 9 And is different from the case of each condition of FIG.

A needle tapered portion 24 having a needle diameter of 50 mu m to 25 mu m is formed in the tip end portion of the needle 6 under Condition 5 within a range of 20 mm from the needle tip. Fig. 6 shows the results of evaluation of the coating step state using the same index as in condition 1.

In this condition 5, since the needle taper portion 24 is provided, it is possible to suppress increase in the flow resistance of the nano Ag ink 16 at the tip of the nozzle as compared with the case of Condition 1, Stable liquid supply to the liquid holding portion 14 formed at the nozzle tip from inside the nozzle becomes possible. As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

In addition, since the needle tapered portion 24 is provided, it is possible to suppress increase in the flow resistance of the nano Ag ink 16 at the tip of the nozzle as compared with the case of Condition 1 at the end of coating, , The needle holder 10 is operated by the control unit 13 so that the start position P1 of the needle tapered portion 24 is located inside the tip of the nozzle 2 It is possible to improve the responsiveness at the time of the operation. As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

- Condition 6 -

In condition 5, the contact angle of the nano-Ag ink on the side surface of the needle 6 was 15 deg. And the contact angle of the nano-Ag ink on the needle tip surface 19 was 15 deg. 19) was set at 10 degrees. The other conditions were the same as in condition 5. Fig. 6 shows the evaluation results of the coating step state using the same index as in condition 1.

In this condition 6, since the needle contact surface 19 has the smallest contact angle, the effect of holding the liquid holding member 14 in the needle tip end surface 19 can be improved as compared with the case of the condition 5. [ As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

In addition, since the needle contact surface 19 has the smallest contact angle, it is possible to improve the effect of holding the liquid holding member 14 at the tip end 19 of the needle at the application end as compared with the case of the condition 5 Therefore, it is possible to improve the responsiveness in separating the liquid holding portion 14. As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since it is possible to shorten the time required for application at the termination, shortening of the production tact can be realized.

- Condition 7 -

The contact angle of the nano-Ag ink of the needle tapered portion 24 was single in the conditions 5 and 6, but in this condition 7, as shown in Fig. 10, Only the regions 25 and 26 in which the contact angle of the nano Ag ink is different are formed on the side surface portion of the needle 6 projecting to the side of the needle 6. The other conditions were the same as in condition 6.

11, the contact angle of the region 25 on the nozzle side is θ6 = 15 ° and the contact angle of the region 26 on the needle tip side is θ7 = 13 °. Fig. 6 shows the results of evaluation of the coating step state using the same index as in condition 1.

In this condition 7, since the needle contact surface 19 has the smallest contact angle, it is possible to improve the effect of holding the liquid holding portion 14 at the tip of the needle as compared with the case of the condition 5. [ The contact angle? 6 of the nozzle-side region 25 in the needle tapered portion 24 which is projected toward the object 4 toward the object 4 at the time of application is smaller than the contact angle? It is possible to improve the effect of holding the nano Ag ink 16 on the needle tip end surface 19 as compared with the case of the condition 6. [ As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

Since the needle contact surface 19 has the smallest contact angle, it is possible to improve the effect of holding the liquid holding portion 14 at the needle tip end surface 19 as compared with the case of the condition 5 at the coating end , Leading to an improvement in responsiveness in separating the liquid holding portion 14. The contact angle? 6 of the nozzle-side region 25 in the needle taper portion 24 that is projected toward the object 4 to be coated 4 from the nozzle tip end face 15 at the time of application is set to a contact angle? It is possible to improve the effect of holding the nano Ag ink 16 on the needle tip end surface 19 as compared with the case of the condition 6. [ As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

- Condition 8 -

In condition 7, θ6 = 15 ° and θ7 = 13 °. In this condition 8, θ6 = 15 ° and θ7 = 10 °. The other conditions were the same as in condition 7. Fig. 6 shows the evaluation results of the coating step state using the same index as in condition 1.

In this condition 8, since the needle contact surface 19 has the smallest contact angle, the effect of holding the liquid holding portion 14 at the tip of the needle as compared with the condition 5 can be improved. The contact angle? 7 of the tip end side region 26 of the needle tapered portion that is projected toward the object 4 side of the nozzle tip face 18 at the time of application is made equal to the contact angle? 3 of the needle tip end face 19, It is possible to improve the effect of holding the nano Ag ink 16 at the tip of the nozzle as compared with the case of Fig. As a result, it is possible to achieve a high speed of elongation and contraction of the liquid holding portion 14, and to achieve stable continuous coating without breaking the liquid holding portion 14.

Since the needle contact surface 19 has the smallest contact angle, it is possible to improve the effect of holding the liquid holding portion 14 at the tip end of the needle as compared with the case of Condition 5 at the coating end. The contact angle? 7 of the tip end side region 26 of the needle tapered portion 24 which is projected toward the object 4 side of the object to be coated 4 from the nozzle tip end face 18 at the time of application is made equal to the contact angle? 3 of the needle tip end face 19 It is possible to improve the effect of holding the nano Ag ink 16 at the tip of the nozzle as compared with the case of the condition 7. As a result, the timing control for stopping the relative movement of the nozzle 2 and the object 4 for ending the application becomes easy, and the position at which the liquid holding portion 14 is separated from the object 4 is the target As shown in FIG. Thus, even at the coating end, the coating can be precisely performed without causing the line width to be thick or broken. In addition, since the time required for application at the termination can be shortened, the production tact can be shortened.

(Industrial availability)

It is an object of the present invention to provide an organic EL or plasma display, a liquid crystal display, a touch panel, a circuit board, a semiconductor, a solar cell, a lithium The present invention can be applied to a printing production process for producing a device such as a secondary battery.

1: liquid
2: Nozzle
3: Nozzle tip
4: object to be coated
5:
6: Needle
7:
8: Electrode plate
9:
10: Needle driver
11: stage
12:
13:
14: liquid collection section at the nozzle tip
15: nozzle inner diameter at nozzle tip
16: Nano Ag ink
17: Needle diameter at nozzle tip
18: nozzle cross section
19: Needle cross section
20: Needle side
21: Clearance between the inner wall of the nozzle and the side surface of the needle at the nozzle line end face
22: area of the contact angle? 4 on the side surface of the needle projecting from the nozzle line end face
23: area of the contact angle &thetas; 5 on the side surface of the needle projecting from the nozzle line end face
24: Needle taper part
25: Area of contact angle? 6 on the nozzle side in the side portion of the needle taper portion
26: Area of contact angle? 7 on the tip side in the side surface of the needle taper portion

Claims (9)

Wherein a nozzle tip of a nozzle in which a liquid is contained is disposed to face the object to be coated and a potential difference is applied between the liquid and the object to be coated to form a liquid gathers extending toward the object to be coated at the tip of the nozzle, Wherein a tip end of a needle disposed in the nozzle is protruded to the liquid holding portion so that a tip end of the liquid holding portion is brought into contact with the object to be coated, Is relatively moved in the horizontal direction, and the liquid is continuously applied to the object to be coated
Electrostatic application method.
The method according to claim 1,
At the end of application, the potential difference is made smaller than that in the application, and when a predetermined time has elapsed, the tip of the needle is retracted to the inside of the nozzle from the tip of the nozzle
Electrostatic application method.
An electrostatic coating apparatus for applying a potential difference between a liquid in a nozzle and an object to be coated to draw out the liquid from the nozzle and apply the liquid onto an object to be coated,
A power source for applying a predetermined voltage between the liquid and the object to be coated;
A needle capable of moving up and down in the nozzle,
A needle driver for vertically driving the needle,
The controller controls the power source unit so as to form the liquid gaseous portion extending toward the object to be coated at the tip of the nozzle at the time of application and drives the needle driver to project the tip of the needle into the liquid gore A control part for relatively moving the object to be coated and the nozzle in a horizontal direction and continuously applying the liquid to the object to be coated after a predetermined time has passed after the tip of the liquid holding part is brought into contact with the object to be coated, Having
Electrostatic application device.
The method of claim 3,
Wherein the control unit is configured to raise the needle until the tip is positioned inside the nozzle when a predetermined time has elapsed after the potential difference is made smaller in the non-spreading of the liquid than during the application
Electrostatic application device.
The method of claim 3,
The needle has a tapered portion that gradually tapers towards the tip
Electrostatic application device.
6. The method of claim 5,
The control section may be configured to operate the needle driving section so that the starting position of the tapered section of the needle is located at a position inside the tip of the nozzle at the non-
Electrostatic application device.
6. The method of claim 5,
Wherein a contact angle of the liquid at an end face of the nozzle is? 1, a contact angle of the liquid at a side face of the needle is? 2, and a contact angle of the liquid at the tip of the needle is? And? 1>? 3.
Electrostatic application device.
8. The method of claim 7,
A region having a contact angle of the liquid of? 4 at the tip side of the needle is smaller than a region where the contact angle of the liquid at the side of the needle is? 2 at a portion which is closer to the object to be coated than the tip of the nozzle at the time of application of the liquid, , And? 2? 4
Electrostatic application device.
9. The method according to any one of claims 3 to 8,
Wherein the gap between the inner wall of the nozzle and the outer wall of the needle is larger than the diameter of the needle at the tip of the nozzle at the time of applying the liquid
Electrostatic application device.

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