JP2009196248A - Method for cleaning screen printing plate - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for cleaning, capable of removing a residual paste or a foreign object stuck to the backside of a screen plate even for a highly thixotropic paste. <P>SOLUTION: In the method 19 for cleaning a screen printing plate, by simultaneously moving a screen plate 5 and an adhesive film 1 held between a squeegee 7 and a drawer roll 3 by the elevation means 14 of the squeegee 7 and the elevation means 11 of the drawer roll 3 while applying pressure to apply shearing force on a paste, thereby achieving low viscosity. At the same time, the adhesive film 1 is taken up by a fixed taking-up tension so as to be folded via the drawer roll 3. Thus, the adhesive film 1 is taken up in the tangential direction of the drawer roll 3 and quickly peeled off from the screen plate 5 when the paste is low in viscosity, and even for a highly thixotropic paste, a residual paste or a foreign object 17 stuck to the backside of the screen plate 5 is removed. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a method for cleaning a screen printing plate used in a screen printing machine.

When screen printing is performed, the screen plate is repeatedly used. However, the adhesion of the paste in the pores of the screen plate 5 causes bleeding on the printing material, which adversely affects the printing accuracy. In addition, foreign matter may adhere to the screen plate, base material, etc., which is unacceptable in terms of quality. Therefore, for each printing cycle, the remaining paste or foreign matter 17 on the back surface of the screen plate 5 (printed material side) is adhered and removed with an adhesive film or the like.

FIG. 1 shows the operation procedure of the prior art. In the prior art, after spreading the adhesive film 1 so as to cover the entire back surface of the screen plate 5, as shown in FIG. 1 (a), the screen plate 5 and the adhesive film 1 are sandwiched so that the squeegee 6 and the support roll 2 The screen plate 5 and the adhesive film 1 are brought into close contact with each other by moving synchronously while applying pressure.

Next, as shown in FIG. 1 (b), after returning the squeegee 6 and the support roll 2 to the cleaning start position, as shown in FIG. 1 (c), the winding roll 4 and the drawing roll 3 are used to remove the screen plate 5 from the screen plate 5. There is a cleaning method in which the adhesive film 1 is peeled off and wound to remove the remaining paste or foreign matter 17. This is disclosed in the following patent document.
JP2001-18367

However, when performed with the above-mentioned conventional technology, when the paste having a high thixotropy used in the present invention is moved synchronously while sandwiching the screen plate and the adhesive film with a squeegee and a pulling roll, The shearing force is applied to the paste, resulting in a low viscosity, but the original viscosity returns to a high state over time.
Therefore, at the stage of peeling the adhesive film from the screen plate, the viscosity of the paste is high, and there may be a case where residual paste or foreign matter remains on the screen plate and cannot be cleaned.

Thixotropy is a thixotropic property, which is a non-Newtonian substance that has a flow characteristic that depends on the time when the apparent viscosity decreases with time at a constant shear rate and gradually recovers when the shear force is removed. is there.

In order to solve the above-described problems, the cleaning method of the present invention includes an unwinding roll for unwinding an adhesive film while adjusting a tension by a driving unit having a torque control function and a brake function, and a drive having a torque control function and a brake function. A winding roll for winding the pressure-sensitive adhesive film while adjusting the tension by means, a drawing roll that winds the pressure-sensitive adhesive film and moves along the back surface of the screen plate, and a drawing roll that comes into contact with the screen plate In a cleaning device for a screen printing plate, comprising: a drawing roll raising / lowering means for raising; a squeegee facing the drawing roll with the screen plate and the adhesive film interposed therebetween; and a squeegee raising / lowering means for pushing a squeegee into the screen plate. The screen plate and the screen plate by the squeegee and the drawing roll. Wearing film are held, in the step of performing the synchronous movement, and wherein the wound into the winding roll while peeling immediately PSA film from the screen plate.

Further, in the cleaning method of the present invention, the unwinding roll, the winding roll, and the drawing roll are arranged on the lower outside of the back side of the screen printing plate, and the drawing roll is placed on the back side of the screen printing plate. A cleaning start point position, wound the adhesive film, covered the cleaning portion on the back side of the screen printing plate, and then returning the drawing roll to the origin position of the drawing roll, It is characterized by performing.

As described above, according to the present invention, the screen plate and the adhesive film are sandwiched between the squeegee and the pulling roll and moved synchronously while being pressed, whereby the shearing force is applied to the paste and the viscosity is reduced. At the same time, the pressure-sensitive adhesive film is wound with a constant winding tension so as to be folded back through the drawing roll. As a result, the adhesive film is wound in the tangential direction of the drawing roll, and immediately peels off from the screen plate when the paste is low in viscosity, and adheres to the back side of the screen plate even for highly thixotropic pastes. Residual paste or foreign matter can be removed.

First, the outline of the screen printing plate cleaning method according to the present invention will be described. Since well-known techniques can be applied to the drive means, guide means, and elevating means described below, illustration or description thereof will be omitted. For example, an electric motor such as a servo motor, an air cylinder, or a hydraulic cylinder can be applied as the driving means, the guide means, and the lifting means.

FIG. 2 (a) shows an initial state of the screen printing plate cleaning apparatus. The screen printing plate cleaning method 19 includes a driving means 12 for unwinding the adhesive film 1 and an unwinding roll 10 having a powder clutch 20, a driving means 13 for winding the adhesive film 1, and a winding roll 4 having a powder clutch 21. A drawing roll 3 having a guide means 16 that moves along the back surface of the screen plate 5, a drawing roll lifting / lowering means 11 for bringing the drawing roll 3 into contact with the screen plate 5, and a drawing roll 3 with the screen plate 5 and the adhesive film 1 interposed therebetween And a squeegee lifting / lowering means 14 for pushing the squeegee 7 into the screen plate 5.

The drawing roll lifting / lowering means 11 and the squeegee lifting / lowering means 14 may be any one of an air cylinder, a hydraulic cylinder, a linear motion motor, and the like. Further, the drive means 12, 13 are provided with a motor having a brake function, and the powder clutches 20, 21 are magnitudes of power (rotational force) transmitted from the drive means 12, 13 to the unwinding roll 10 and the winding roll 4. Can be adjusted freely. The operation of the powder clutches 20 and 21 may be achieved based on an electrical signal sent from a computer or the like. The torque control means comprising the drive means 12 and 13 and the powder clutches 20 and 21 can be realized by replacing with a servo motor or torque motor. The guide means 16 is driven and transmitted by a servo motor and a ball screw, and is guided by a linear guide.

Next, the operation of the screen printing plate cleaning method of the present invention will be described with reference to FIGS. 2 (b) and 2 (c). FIG. 2 (b) shows a state where the adhesive film 1 is unwound. In the unwinding roll 10, the driving means 12 is rotated in the F direction opposite to the direction in which the adhesive film 1 is unwound, and the input voltage of the powder clutch 20 is adjusted so as to obtain a desired tension. On the other hand, using the brake function of the driving means 13, the powder clutch 21 is applied with an input voltage of 100% to stop the rotation of the winding roll 4. In this state, by moving the drawing roll 3 arranged on the lower outer side of the screen plate 5 to the cleaning start position in the direction of arrow D along the back surface of the screen plate 5 by the guide means 16, the adhesive film 1 has a certain tension. Covers the cleaning site 15 while being unwound.

FIG. 2 (c) shows how the screen printing plate is cleaned and how the adhesive film 1 is wound up. Using the brake function of the driving means 12, the powder clutch 20 is applied with an input voltage of 100% to stop the rotation of the unwinding roll 10. On the other hand, in the winding roll 4, the driving means 13 is rotated in the F ′ direction in which the adhesive film 1 is wound, and the input voltage of the powder clutch 21 is adjusted so as to obtain a desired tension. In this state, the adhesive film 1 is wound with a constant tension by performing the synchronous movement in the direction of the arrow D ′ while holding and pressing the screen plate 5 and the adhesive film 1 by the squeegee lifting means 14 and the drawing roll lifting means 11. Taken.

By the above operation, when the paste is reduced in viscosity, the adhesive film is wound in the tangential direction of the drawing roll and is immediately peeled off from the screen plate. The residual paste or foreign matter 17 adhering to the back side of the screen plate can be removed.

3 and 4 are schematic views showing other embodiments. Both figures show the case where the cleaning operation can be performed in a reciprocating manner. FIG. 3 (a) shows a case where the unwinding roll 10, the winding roll 4 and the drawing roll 3 are provided on one side. In the example of FIG. 2, the configuration is complicated because there are guide rolls 8 and 9 in addition to the above-described rolls. However, in the case shown in FIG. 3, the configuration can be simplified.

Next, the operation of FIG. 3 will be described.
As shown in FIG. 3 (b), similar to the operation shown in FIG. 2, after the screen plate 5 and the adhesive film 1 are gripped by the squeegee lifting means 14 and the pulling roll lifting means 11 of the squeegees 6 and 7, the synchronous movement is performed. The adhesive film 1 is immediately peeled off from the screen plate 5 while performing. Here, the squeegee 6 is used in the forward cleaning operation, and the squeegee 7 is used in the reverse cleaning operation.

Further, after the cleaning operation once, the adhesive film 1 with the remaining paste or foreign matter 17 attached thereto is prevented from adhering to the screen plate 5 in the next cleaning operation by the driving means 12 and 13 and the powder clutches 20 and 21. Has a function to send 1 out.

Finally, when the cleaning operation is finished, as shown in FIG. 3A, the various rolls and squeegees 6 and 7 return to the initial positions.

By continuously performing the above operations, the cleaning time can be shortened because the screen plate 5 can be reciprocated when cleaning the screen plate 5 twice or more.

FIG. 4 shows a case where the unwinding roll 10 and the winding roll 4 are provided on both sides of the drawing roll 3 with respect to FIG. The operation and effect of FIG. 4 are the same as those of FIG.

     The present invention is a useful technique capable of cleaning even a screen plate printed with a paste having no thixotropy or a paste having low thixotropy.

Conventional screen printing plate cleaning operation Screen printing plate cleaning operation according to an embodiment of the present invention Screen printing plate cleaning operation according to another embodiment of the present invention Screen printing plate cleaning operation according to another embodiment of the present invention

Explanation of symbols

1: Adhesive film
2: Support roll
3: Drawing roll
4: Winding roll
5: Screen version
6, 7: Squeegee
8, 9: Guide roll
10: Unwinding roll
11: Pulling roll lifting means
14: Squeegee lifting means
12, 13: Drive means
15: Cleaning part
16: Guide means
17: Residual paste, foreign matter
18: Cleaning direction
19: Screen printing plate cleaning method
20, 21: Powder clutch

Claims (2)

A winding roll for unwinding the adhesive film while adjusting the tension by a driving means having a torque control function and a brake function, and a winding roll for winding the adhesive film while adjusting the tension by a driving means having a torque control function and a brake function A roll, a draw roll wound around the adhesive film and moved along the back surface of the screen plate, a draw roll lifting means for raising the draw roll so as to contact the screen plate, the screen plate and the adhesive film A screen printing plate cleaning device having a squeegee opposed to the drawing roll and a squeegee lifting means for pushing the squeegee into the screen plate, wherein the screen plate and the adhesive film are moved by the squeegee and the drawing roll. In the process of gripping and performing synchronous movement, Screen printing plate of the cleaning method characterized by winding the down plate to said winding roll while peeling immediately PSA film. The unwinding roll, the winding roll, and the drawing roll are arranged on the lower outside of the back side of the screen printing plate, and the drawing roll is moved along the back surface of the screen printing plate to the cleaning start position. The cleaning operation is performed in a step of winding the adhesive film and covering the cleaning portion on the back surface of the screen printing plate, and then returning the drawing roll to the origin position of the drawing roll. The method for cleaning a screen printing plate as described in 1.

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