JP3549705B2 - Printing method and printing apparatus - Google Patents

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a printing method for transferring a printing paste held on a plate to a printing medium, and a printing apparatus for performing the printing method.
[0002]
[Prior art]
Conventionally, for example, in flat plate stencil (screen) printing in which cream solder is printed on lands of a printed circuit board, as shown in FIGS. 18A and 18B, corresponding to the lands 5 of the printed circuit board 4. A screen mask (metal mask) 1 having through holes 1a arranged in a predetermined pattern is positioned at a predetermined position on the substrate 4 and brought into contact therewith. Next, as shown in FIGS. 18C and 19A and 19B, the cream solder 2 is supplied to one end of the screen mask 1 and the squeegee 3 removes the cream solder 2 from one end of the screen mask 1 to a predetermined position. The cream solder 2 is filled in the through holes 1a of the screen mask 1 by moving the solder mask 2 in the direction shown in FIG. Next, as shown in FIG. 18 (D), by removing the screen mask 1 from the substrate 4, the cream solder 2 in the through-hole 1a of the screen mask 1 is moved onto the land 5 of the substrate 4, and as shown in FIG. The cream solder layer 2a is formed on the land 5 of the substrate 4 as shown in FIG.
[0003]
However, in the above structure, as shown in FIG. 19C, when the screen mask 1 is separated from the substrate 4, a part of the cream solder 2 is formed in the through hole 1a of the screen mask 1 due to the viscosity of the cream solder itself. A phenomenon occurs in which the cream solder spreads between the remaining cream solder 2 and the cream solder 2 placed on the land 5 of the substrate 4. As a result, as the screen mask 1 moves away from the substrate 4, the relative deformation (shear speed gradient) of the above-mentioned straddle cream solder increases, and the cream solder is torn off at an arbitrary portion between the screen mask 1 and the substrate 4 and torn off. As shown in FIG. 19D, a part of the cream solder adheres to the portion other than the land 5 on the substrate 4 and adheres to the periphery of the through hole 1a on the back surface of the screen mask 1 on the substrate side, and the next time printing is performed. This causes printing bleeding, a bridge that erroneously adheres to the adjacent cream solder layer 2a on the substrate 4, or the cream solder adheres to the screen mask side, so that a sufficient cream solder layer is not formed on the substrate. There was a problem.
[0004]
[Problems to be solved by the invention]
Therefore, the object of the present invention is to solve the above problems, it is possible to accurately tear the printing paste between the plate and the substrate holding the printing paste, without causing a bridge, It is an object of the present invention to provide a printing method and a printing apparatus in which the printing paste does not remain on the plate side to cause printing bleeding and the supply of the printing paste to the substrate does not become insufficient.
[0005]
Means for Solving the Problems and Effects of the Invention
In order to achieve the above object, the present invention increases the temperature of a portion near a portion of a printing plate that holds a printing paste, reduces the viscosity of the printing paste attached to the printing paste holding portion, and reduces the printing paste. Is configured to be easily separated from the holding portion to facilitate printing on a printing medium.
According to the first aspect of the present invention, a printing paste having a property of decreasing the viscosity with increasing temperature is held on the plate,
Portion of the plate where the printing paste is heldIs heated by electromagnetic induction heating.Raise the temperature of the printing paste that comes into contact with the held portion to reduce the viscosity of the printing paste to facilitate separation of the printing plate and the printing paste,
Separate the printing paste held by the plate from the plate and print it on the printing substrateAnd
After the printing paste is printed on the printing medium, a printing state is detected, and the condition of the electromagnetic induction heating of the plate or the separation condition of the printing plate and the printing medium is controlled based on the detection result. A printing method is provided.
[0006]
According to a second aspect of the present invention, in the first aspect, the plate has an opening having a predetermined pattern for holding the printing paste, and the plate contacts the printing medium after the plate contacts the printing medium. A printing method for printing the printing paste in the opening on the printing medium by relatively separating the printing medium from the printing medium.
According to a third aspect of the present invention, there is provided the printing method according to the second aspect, wherein the electromagnetic induction heating device for performing the electromagnetic induction heating performs the electromagnetic induction heating on the plate in a non-contact manner.
According to a fourth aspect of the present invention, in the third aspect, an interval between the electromagnetic induction heating device and the printing plate is set to a size such that a predetermined induction current flows through the printing plate by the electromagnetic induction heating device. Provide a printing method.
According to a fifth aspect of the present invention, in the second aspect, there is provided a printing method in which the electromagnetic induction heating device for performing the electromagnetic induction heating contacts the plate to perform the electromagnetic induction heating.
[0007]
According to a sixth aspect of the present invention, there is provided the printing method according to any one of the second to fifth aspects, wherein the electromagnetic induction heating is performed after the holding of the printing paste in the opening of the plate is completed. .
According to a seventh aspect of the present invention, in any one of the second to sixth aspects, the opening is a through hole, the printing plate is a screen mask, and the printing paste is moved into the through hole by moving a squeegee. A printing method for filling is provided.
According to an eighth aspect of the present invention, in any one of the second to seventh aspects, the electromagnetic induction heating causes the printing paste to have a high temperature at a portion in contact with a portion held by the plate, Provided is a printing method having a temperature gradient such that the temperature gradually decreases as the distance from the part increases.
According to a ninth aspect of the present invention, there is provided the printing method according to any one of the second to eighth aspects, wherein the induction current for generating the electromagnetic induction heating flows along a longitudinal direction of the opening of the plate.
[0008]
According to the tenth aspect of the present invention, a printing plate is placed on and contacted with a printing medium, a printing paste is supplied to the printing plate, and the printing paste is moved in a predetermined direction from one end of the printing plate by a squeegee. By filling the printing paste in the opening of the plate, and removing the plate from the printing medium, the printing paste in the opening of the plate is moved onto the printing medium to form a printing paste layer. In a printing apparatus formed on a printing medium,
A plate having an opening of a predetermined pattern for holding a printing paste having a property of decreasing viscosity with increasing temperature,
The temperature of the portion where the printing paste is held in the plate is increased by electromagnetic induction heating to reduce the viscosity of the printing paste that comes into contact with the held portion and facilitate separation of the printing paste from the plate. An electromagnetic induction heating device,
After the printing plate comes into contact with the printing medium, the printing plate and the printing medium are relatively separated from each other, and the printing paste held in the opening of the printing plate is separated from the printing plate and printed on the printing medium. Printing paste separating device,
After the printing paste is printed on the printing medium, a printing state is detected, and control for controlling conditions of the electromagnetic induction heating of the plate or separation conditions of the printing plate and the printing medium based on the detection result is performed. Department
The present invention provides a printing apparatus provided with:
[0009]
The present invention11According to the aspect, the second10In an embodiment, the electromagnetic induction heating device for performing the electromagnetic induction heating provides a printing device that performs the electromagnetic induction heating on the plate in a non-contact manner.
According to a twelfth aspect of the present invention,11In an aspect, the present invention provides a printing apparatus configured such that a distance between the electromagnetic induction heating device and the printing plate is set to a size such that a predetermined induction current flows through the printing plate by the electromagnetic induction heating device.
The present inventionThirteenAccording to the aspect, the second10In another aspect, the present invention provides a printing apparatus configured to perform the electromagnetic induction heating by contacting the plate with the electromagnetic induction heating apparatus that performs the electromagnetic induction heating.
The present invention14According to the aspect, the tenth to the tenthThirteenIn any of the aspects, there is provided a printing apparatus configured so that the electromagnetic induction heating is performed after the holding of the printing paste in the opening of the plate is completed.
The present inventionFifteenAccording to the aspect, the tenth to the tenth14In any one of the embodiments, a printing device is provided in which the opening is a through hole, and the plate is a screen mask, and the printing paste is filled in the through hole by moving a squeegee.
[0010]
The present invention16According to the aspect, the tenth to the tenthFifteenIn any one of the aspects, by the electromagnetic induction heating, the printing paste has a temperature gradient such that the temperature of a portion in contact with a portion held by the plate is high, and the temperature gradually decreases as the distance from the portion increases. And a printing device having the same.
The present invention17According to the aspect, the tenth to the tenth16In any of the aspects, there is provided a printing device wherein the induction current for generating the electromagnetic induction heating flows along a length of the plate opening.
[0011]
According to the configuration of the above aspect of the present invention, as a result of heating the plate itself by induction heating, the portion of the printing paste held by the plate (the portion in contact with the inner wall surface of the through hole of the printing paste plate and its vicinity) The temperature rises and its viscosity decreases as compared with the inner part. As a result, the adhesive strength of the printing paste between the plate and the printing paste is reduced, the resistance when the printing paste is easily separated from the plate is reduced, and the plate separating operation can be performed well. Therefore, since the printing paste does not remain on the printing plate side, it does not cause printing bleeding at the time of next printing, and supplies the printing paste to the printing medium side in a predetermined amount, that is, a predetermined shape and a predetermined position, and prints the printing paste layer. Can be formed. Further, according to the above aspect of the present invention, the resistance of the printing paste on the inner wall surface portion of the through hole of the plate is reduced, so that the printing paste is separated from the conventional plate separation speed (eg, 0.1 mm / s or more and less than 1 mm / s). A good printing result can be obtained even if the speed is set to a high speed (for example, 1 mm / s or more and 3 mm / s or less) or without speed control.
[0012]
Further, according to the induction heating, the plate itself generates heat, so that the plate can be radiated immediately after the induction heating operation is stopped, and other parts other than the plate are not heated, and the next printing operation or the like is performed. And the devices around the plate are not adversely affected. On the other hand, in a method of heating the plate by radiating heat from the outside of the plate such as hot air, radiant heating (infrared heating), or conduction heating, the members and air around the plate are also heated, Since the heating device itself also becomes hot, the members and air surrounding the heating device are also heated, which may adversely affect the next printing operation and the like and the devices around the plate. Further, such a method of transferring heat from the heating device to the plate has a disadvantage that the heat is transmitted not only to the plate but also to members around the heating device, the plate, and air, resulting in poor heating efficiency.
In addition, when induction heating is performed in a non-contact manner without bringing the induction heating device into contact with the plate, the induction heating device does not contact the printing paste on the surface of the plate, so that the induction heating device is not stained by the printing paste. In addition, by making it non-contact, when there is an electronic component on the lower surface of the printing medium, the distance from the electronic component is increased, and it is possible to prevent the electronic component from being adversely affected during induction heating. it can.
[0013]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, an embodiment according to the present invention will be described in detail with reference to FIGS. 1 (A) to 17, 20, 21, and 22. FIG.
As shown in FIGS. 1A to 1D, a printing method according to an embodiment of the present invention is a flat-plate stencil (screen) printing method for printing a printing paste, for example, cream solder, on a land of a printed circuit board. It is about. The printing method according to this embodiment is as follows. First, as shown in FIG. 1A, a screen mask (metal mask) 11 having through holes 11a arranged in a predetermined pattern corresponding to lands 15 of a printed circuit board 14 is positioned at a predetermined position on the substrate 14. Contact. Next, the cream solder 12 is supplied to one end of the screen mask 11, and the squeegee 13 moves the cream solder 12 from one end of the screen mask 11 in a predetermined direction, thereby filling the cream solder 12 into the through holes 11a of the screen mask 11. I do. Next, as shown in FIG. 1B, the temperature of the inner wall surface of the through hole 11a of the screen mask 11 is increased by induction heating. At this time, the temperature of the inner wall surface is increased until the viscosity of the cream solder 12 to be used decreases to a level that makes it difficult to adhere to the inner wall surface of the through-hole 11 a of the screen mask 11. Next, as shown in FIG. 1C, by removing the screen mask 11 from the substrate 14, the cream solder 12 in the through hole 11 a of the screen mask 11 is moved onto the land 15 of the substrate 14. The cream solder layer 12a is formed on the land 15 of the substrate 14 as shown in FIG. At this time, since the viscosity of the cream solder 12 is reduced by the induction heating, the cream solder 12 in the through hole 11a of the screen mask 11 hardly adheres to the inner wall surface of the through hole 11a. Therefore, even if the screen mask 11 is removed from the substrate 14, the cream solder 12 in the through hole 11a remains formed on the land 15 of the substrate 14 as it is, and the cream solder layer 12a having a predetermined shape can be formed at a predetermined position. it can.
[0014]
The printing method according to the above embodiment can be carried out by the printing apparatus according to the embodiment of the present invention shown in FIGS. A more specific operation of the printing method performed by the printing apparatus is shown in a flowchart of FIG. In FIG. 2, the printing device includes a substrate loading / unloading device 21 having a loading device 21a and a loading / unloading device 21b, a substrate support device 22, a screen mask 11, a squeegee head driving device 24, an XYθ position correcting device 25, and a plate separation. The stage unit 20 including the device 26 and the screen mask heating device 27 including the induction heating unit 28 and the timer 29 are driven under the control of the control unit 34. The control unit 34 receives the board position recognition correction information from the board position recognition and correction unit 30 including the processing calculation unit 31 and the recognition camera unit 32, and also processes the processing calculation unit 39 and the print state detection unit 40. The print inspection information is input from a print inspection unit 38 having an inspection reference storage unit 41. Further, process information is input and output between the control unit 34 and the process control unit 35 having the processing calculation unit 36 and the non-defective print database 37, and information on the printing state is input from the print inspection unit 38. , Process control. Further, the control unit 34 displays information such as the state of the printed cream solder 12 on the display unit 33 as a result of the operation and inspection as needed.
[0015]
The substrate 14 is carried into the stage unit 20 by the carry-in device 21a of the substrate carry-in / carry-out device 21, is moved to the print position after being corrected in position by the stage unit 20, and is printed at the print position. Is carried out of the printing apparatus by the carry-out device 21b of the substrate carry-in / carry-out device 21.
In the stage section 20, first, the substrate 14 is held in position by the substrate support device 22 disposed on the stage section 20. The method of holding the position of the substrate 14 includes, for example, a method of vacuum-suctioning the substrate 14 with a large number of suction holes opened on the surface of the substrate support device 22 and a method of supporting the lower surface of the substrate 14 with a large number of backup pins. . In the position holding state of the substrate 14, the recognition camera unit 32 of the substrate position recognition / correction unit 30 recognizes a position correction mark (not shown) of the substrate 14. The processing operation unit 31 calculates a position shift between the recognized position of the substrate 14 and the position of the screen mask 11 and calculates a position correction amount of the substrate 14 for correcting the position shift. The calculation result is input to the XYθ position correction device 25 of the stage unit 20. Based on the input position correction information, the position of the substrate 14 with respect to the screen mask 11 is corrected by the XYθ position correction device 25 of the stage unit 20. That is, the XYθ position correcting device 25 corrects the position of the substrate 14 in the orthogonal XY directions along the horizontal plane of the printing device and in the θ direction around the vertical Z axis with respect to the screen mask 11 based on the position correction information. Be done. The XYθ position correcting device 25 places a Y-direction table 25b movable in the Y direction on an X-direction table 25a movable in the X direction (substrate loading / unloading direction), and further places the Y-direction table 25b thereon. A rotatable θ-direction table 25c is mounted on the substrate 14, and each table is moved by a position correction amount in each direction to correct the position of the substrate 14. Note that the position correction in the X direction is performed after the position correction in the Y direction and the θ direction is completed and before the substrate 14 comes into contact with the screen mask 11 after the substrate 14 is moved to the printing position and stopped. This is performed by the X-direction table 25a.
[0016]
FIG. 20 shows an X-direction drive device 20x also serving as the X-direction position correction device. In FIG. 20, an X-direction table 25a is arranged movably in the X direction along a pair of linear guides 25m extending in the X direction, and the screw shaft 25n is rotated forward and reverse by a forward and reverse rotation drive of a drive motor 25p. An X-direction table 25a fixed to a nut 25r screwed with the screw shaft 25n is moved back and forth along the X direction.
The substrate 14 held by the substrate support device 22 is moved to a printing position in the X direction by the X direction driving device 20x of the stage unit 20. In this printing position, the substrate 14 is located below the screen mask 11 and is raised by the plate separating device 26 until the upper surface of the substrate 14 contacts the lower surface of the screen mask 11. Then, while the lower surface of the screen mask 11 is in contact with the upper surface of the substrate 14, the cream solder 12 is supplied to one end of the screen mask 11 in the X direction, and the squeegee 13 The cream solder 12 is filled in the through-hole 11a of the screen mask 11 by moving along the X direction from the one end to the other end in the direction.
The screen mask 11 is formed by, for example, forming an opening formed of a through hole 11 a corresponding to a copper conductive pattern portion (land) 15 of the substrate 14 on a nickel or stainless steel plate having a thickness of about 150 μm. .
[0017]
The squeegee head driving device 24 moves the squeegee 13 for filling the cream solder 12 into the through hole 11 a of the screen mask 11 on the screen mask 11. The squeegee 13 is formed of a flat plate or a plate having a sword-shaped (substantially pentagonal) cross-sectional side shape. The squeegee head 24a is screwed to the ball screw 24b by driving the motor 24c to rotate the ball screw 24b in the normal or reverse direction. Is moved back and forth along the axial direction of the ball screw 24b to move the squeegee 13 on the screen mask 11. The squeegee head 24a can move up and down by forward and reverse rotation of a motor 24d. The inclination angle of the squeegee 13 with respect to the screen mask 11 can also be adjusted by the cylinder 24f. That is, the squeegee 13 is rotatably supported at a portion (not shown), and the inclination of the squeegee 13 can be adjusted by rotating the one end of the squeegee 13 by driving the cylinder 24f to rotate the squeegee 13 about the support point.
The lower end surface of the cream solder 12 filled in the through hole 11a of the screen mask 11 is in contact with the land 15 of the substrate 14 corresponding to the through hole 11a. Is separated from the substrate 14 so that the cream solder layer 12 a is formed on the land 15 of the substrate 14.
[0018]
FIG. 21 shows an example of the plate separating device 26. In FIG. 21, the drive nut 25v is rotated forward and reverse through a belt 25u by forward and reverse rotation drive of an AC servomotor 25t, and a screw shaft 25w screwed with the nut 25v is moved up and down. Is moved up and down to move the substrate 14 up and down. Therefore, when the substrate 14 is moved along the X direction from the substrate position correcting operation position to the printing position below the screen mask 11 by the X direction driving device 20x of the stage section 20, the AC servo motor 25t of the plate separating device 26 is operated. By driving, the substrate 14 is raised until the upper surface of the substrate 14 contacts the lower surface of the screen mask 11. On the other hand, after printing is completed, the substrate 14 is lowered with respect to the screen mask 11 by driving the AC servomotor 25t of the plate separating device 26 in order to perform the plate separating operation. The substrate 14 separated from the plate is carried out of the printing apparatus by the substrate carrying-out device 21b.
[0019]
FIG. 22 shows another plate separating device. 22, reference numeral 402 denotes a stage (substrate support device); 417, an AC servo controller; 414, an AC servo motor controlled by the AC servo controller 417; 408, a ball screw rotated forward and reverse by the AC servo motor 414; The upper bearing of the ball screw 408, 410 is the lower bearing of the ball screw 408, 411 is a pulley on the ball screw 408 side, 412 is a pulley on the AC servomotor 414 side, 413 is a timing belt, and 415 is a linear guide for raising and lowering the stage 402. It is a guide. In this plate separating device, a stage (substrate support device) 402 can be moved up and down at an arbitrarily set speed and range by an AC servo controller 417, an AC servo motor 414, and a ball screw 408. Eleven plate separation speeds can be arbitrarily adjusted.
[0020]
Immediately before performing the above-described plate separating operation, in other words, immediately after printing of the cream solder 12 is completed, the screen mask 11 is heated by induction heating by the screen mask heating device 27. As shown in FIGS. 5 and 6, the screen mask heating device 27 arranges the ring-shaped induction coil 28a of the induction heating unit 28 on the screen mask 11 at a predetermined distance. Then, when the cream solder 12 is filled in the through hole 11a of the screen mask 11, a current is applied to the induction coil 28a for a time set by the timer 29, for example, for a time within several msec to several seconds, and an induction magnetic field is generated. Then, the screen mask 11 itself is directly heated by induction heating by passing an induced current through the screen mask 11 itself. As an example of the induction coil 28a, a circular donut shape having an inner wire diameter of 50 mm, an outer diameter of 170 mm, and a thickness of 2 mm has a low electric resistance (such as Joule heat) of 35 enameled wires or copper wires. The conductor is wound with a winding number h = 21 to form an induction coil. As the induction heating conditions, at a voltage of 100 V and 60 Hz, an electric power of 1400 W is supplied for only a few seconds to perform the induction heating. In the present embodiment, the induction coil 28a is arranged in a non-contact state apart from the upper surface of the screen mask 11 by a predetermined distance as shown in FIG. At the time of printing the cream solder 12, it may be retracted from above the screen mask 11 so as not to hinder the printing of the cream solder 12, while at the time of induction heating, it may be moved above the screen mask 11 to enable induction heating. The distance between the induction coil 28a and the screen mask 11 is preferably set to a size such that a predetermined induction current flows through the screen mask 11 by the induction coil 28a.
[0021]
In the above induction heating, the screen mask 11 is made of a conductive material such as stainless steel, so that an induction current flows. However, stainless steel or the like has a higher resistance than copper, so that the screen mask itself generates heat. The cream solder 12 has a small solder particle diameter or is creamy due to flux and is not conductive, so that no induced current flows and no heat is generated. Therefore, as shown in FIG. 7, when the screen mask 11 is heated by induction heating, the temperature of the inner wall surface of the through hole 11 a of the screen mask 11 rises. While the temperature rises in the contacting part and the surrounding area, the temperature does not rise in the central part of the cream solder 12, and the central part of the cream solder 12 and the outer peripheral part (the part in contact with the through hole 11a). A temperature gradient is formed between them as shown in FIG. That is, the temperature of the portion of the cream solder 12 that contacts the inner wall surface of the through hole 11a is high, and the temperature gradient gradually decreases from the portion toward the center of the cream solder 12. . As a result, as shown in FIG. 7A, the viscosity of the cream solder 12 is lower at the outer peripheral portion than at the central portion. This is because the cream solder 12 has the characteristic as shown in FIG. 8, that is, the characteristic that the viscosity decreases as the temperature increases. By this induction heating, the viscosity of the cream solder 12 between the inner wall surface of the through hole 11a of the screen mask 11 and the cream solder 12 contacting the inner wall surface decreases, and the cream solder 12 It becomes easy to separate from the through-hole 11a, and the separation of the plate can be performed well.
[0022]
As one example of the material of the cream solder 12, a material containing 90% by weight of metal powder and 10% by weight of flux is preferable. About 62% by weight of the metal powder is tin, the remainder is lead, and the particle size is 20 to 40 μm. The flux contains 75 to 40% by weight of alcohol or the like as a solvent, and the remaining solid content is 25 to 60% by weight. This solid contains rosin, activator, and thixotropic agent. A specific example of a cream solder product is a Panasonic solder cream with a product number MR7125 of 63% by weight of tin and 37% by weight of lead.
As a material of the screen mask 11, a stainless steel (eg, SUS304) such as nickel-chromium or a metal such as nickel is preferable. Further, a screen mask in which a conductive vapor-deposited film or a plated film is formed on the surface of a synthetic resin such as polyimide and the inner wall surface of the through hole can be used. In this case, electromagnetic induction can be generated at a portion of the conductive deposition film or plating film on the inner wall surface of the through hole.
[0023]
Further, when the substrate 14 as the printing medium is made of copper having excellent conductivity, the substrate 14 hardly generates heat due to electromagnetic induction, and does not adversely affect electronic components and the like on the substrate.
The print inspection unit 38 determines the state of the cream solder layer 12 a formed on the land 15 of the substrate 14, that is, the shape and position of the cream solder layer 12 a, as a camera or a laser length measuring device as an example of the print state detection unit 40. The volume of the cream solder layer 12a and the amount of displacement are calculated by the processing calculation unit 39 based on the measurement result. The laser length measuring device irradiates a laser to the cream solder layer 12a and calculates the height and the like of the cream solder layer 12a from the position of the reflected light. The above calculation result is compared with the inspection standard stored in the inspection standard storage unit 41 to determine whether the printing is good or not, and the determination result is output to the control unit 34. Is numerically represented, and the numerical value is also output to the control unit 34. This determination operation is performed, for example, by calculating the height, width, volume, and the like of the cream solder layer 12a from an image captured by the camera of the printing state detection unit 40 or position data measured by a laser length measuring device, and storing the inspection reference. This is performed by comparing the determination data such as the height, width, and volume of the cream solder layer stored in the section 41 with the calculated values in the processing operation section 39 to determine whether the printing is good.
[0024]
The process control unit 35 changes the setting of the parameters of the printing apparatus based on the data of the printing state of the cream solder layer 12 after printing by the print inspection unit 38. Here, the above-mentioned parameters are, for example, parameters of each equipment stored in the non-defective print database 37 (for example, printing speed, inclination angle of the squeegee 13, ambient temperature at the time of printing (for example, squeegee in the order of importance). , The temperature of the screen mask, the temperature of the substrate, and the temperature of the air around them), the printing pressure, in other words, the pressure at which the squeegee 13 is pressed against the screen mask 11, the profile of the plate release speed and acceleration of the substrate 14. Etc.) and induction heating conditions (eg, heating output, heating time, heating start timing, etc.). The relationship between these parameters and print quality is stored as a database, and the processing operation unit 36 of the process control unit 35 calculates the optimal parameters.
[0025]
Next, the printing method performed by the printing apparatus will be described with reference to the flowchart of FIG. Note that this series of operations is controlled by the control unit 34.
In step S <b> 1, the substrate 11 is loaded into the stage unit 20 by the loading device 21 a of the substrate loading / unloading device 21.
Next, in step S2, the substrate 14 carried into the stage unit 20 is held by the substrate support device 22.
Next, in step S <b> 3, the position of the substrate 14 held by the substrate support device 22 is recognized by the substrate position recognition / correction unit 30, and the position correction amount of the substrate 14 with respect to the screen mask 11 is calculated.
Next, in step S4, the position of the substrate 14 in the XYθ direction with respect to the screen mask 11 is corrected by the XYθ position correction device 25 of the stage unit 20 based on the calculated position correction amount.
Next, in step S5, the substrate 14 is positioned at a printing position below the screen mask 11 by the stage unit 20, and the substrate 14 is raised by the stage unit 20 so that the screen mask 11 contacts the upper surface of the substrate 14. .
[0026]
Next, in step S6, the squeegee 13 is moved on the screen mask 11 to fill the cream solder 12 into the through holes 11a of the screen mask 11.
Next, in step S7, it is determined whether or not the screen mask 11 is to be induction-heated. When the induction heating is not performed, for example, when the cream solder 12 is easily separated from the through hole 11a, the process proceeds to step S8. In the case of induction heating, the process proceeds to step S9, in which a timer 29 is set to a predetermined heating time, and the screen mask 11 is set by the induction coil 28a of the induction heating unit 28 immediately after the printing of the cream solder 12 in step S10. Induction heating.
In step S8, when the induction heating is performed, the plate separating operation is performed immediately after the induction heating. That is, by driving the plate separating device 26 of the stage unit 20, the substrate 14 is lowered with respect to the screen mask 11 to separate the substrate 14 from the screen mask 11, and the cream solder 12 is removed from the through hole 11 a of the screen mask 11. The image is transferred onto the land 15 of the substrate 14. When the induction heating is not performed, the above-described separating operation is performed after the printing of the cream solder 12, and the cream solder 12 is transferred from the through hole 11 a of the screen mask 11 onto the land 15 of the substrate 14.
[0027]
Next, in step S12, the shape and position of the cream solder layer 12a formed on the substrate 14 are inspected by the print inspection unit 38.
Next, in step S13, as a result of the inspection, it is determined whether the printing state is good. When it is determined that the printing state is good, the process proceeds to step S14, and in step S14, the substrate 14 is unloaded from the printing device by the unloading device 21b, and a series of printing operations is completed. If it is determined in step S13 that the printing state is defective, the process proceeds to step S15, where the process control unit 35 changes the design of the process parameters, and ends a series of printing operations. The next cream solder 12 is printed based on the information on the optimum conditions whose design has been changed in step S15, and the plate separating process in step S8 after the printing and the induction heating process of the screen mask 11 in step S10 are performed. I have to. In some cases, the cream solder layer determined to be defective in printing is removed, a new printing operation is performed again under the conditions changed in step S15, and the plate separation step and step S8 in step S8 after printing. The induction heating step of the screen mask 11 in S10 may be performed.
In this flowchart, as an example, a case where the plate separation condition is changed in design and the plate separation process in step S8 is performed, and a case where the induction heating condition is changed in design and the induction heating process in steps S9 and S10 is performed are illustrated. . The design change of the parameters does not change the design of all the parameters at the same time, but changes the design of only the parameters appropriately selected according to the printing state.
[0028]
According to the above-described embodiment, as a result of heating the screen mask 11 by induction heating, the temperature of the outer peripheral portion of the cream solder 12 contacting the inner wall surface of the through hole 11a of the screen mask 11 rises as compared with the central portion thereof. The viscosity will decrease. As a result, the adhesive strength between the inner wall surface of the through-hole 11a of the screen mask 11 and the cream solder 12 is reduced, and the cream solder 12 is easily separated from the screen mask 11, so that the plate separating operation can be performed satisfactorily. It can be carried out. Therefore, the cream solder 12 does not remain on the screen mask 11 side, so that the printing bleed does not occur at the next printing, and the cream solder 12 is supplied to the substrate 14 side in a predetermined amount, that is, in a predetermined shape and a predetermined position. The solder layer 12a can be formed by printing.
[0029]
According to the induction heating, since the screen mask 11 itself generates heat, the heat of the screen mask 11 can be released immediately after the induction heating operation is stopped, and other members other than the screen mask 11 are not heated. In addition, there is no adverse effect on the next printing operation or the like and the devices around the screen mask 11. On the other hand, in a method of heating the screen mask 11 by simply radiating heat from the outside of the screen mask 11 such as hot air, radiant heating (infrared heating), or conduction heating, members or air around the screen mask 11 are heated. Is also heated, and the heating device itself is also heated, so that the members and air surrounding the heating device are also heated, which may adversely affect the next printing operation and the like and the devices around the screen mask 11. is there. Further, in the method of transferring heat from the heating device to the screen mask 11 as described above, since heat is transferred not only to the screen mask 11 but also to the heating device, members around the screen mask 11 and air, there is a disadvantage that heating efficiency is poor. is there.
[0030]
Further, when induction heating is performed without contacting the induction heating unit 28 with the screen mask 11, the induction coil 28 a of the induction heating unit 28 does not contact the cream solder 12 remaining on the surface of the screen mask 11. The coil 28a is not stained by the cream solder 12. In addition, by making it non-contact, when there is an electronic component on the lower surface of the substrate 14, the distance from the electronic component becomes large, and it is possible to prevent the electronic component from being adversely affected during induction heating. .
Here, an experiment was conducted to determine how finely the cream solder 12 having a fine pattern can be well separated from the through hole 11a by induction heating. The diameter of the through hole was about 0.1 mm, and the distance between the centers of the through holes, that is, the pitch between adjacent through holes was 0.2 mm. The ambient temperature of air, cream solder, screen mask and the like was 23 ° C. The experimental results are shown in FIGS. As shown in FIGS. 11A and 11B, in this experiment, when the shearing force of the cream solder 12 filled in the through hole 11a of the screen mask 11 at the time of releasing the plate, the pitch of the through hole is 0. No reduction in the shearing force is observed in a portion of 0.2 mm or less, and the pitch of 0.2 mm is the limit of the fine printing. When the distance d from the inner wall surface of the through hole is 0.05 mm or less, a large reduction in the shearing force is observed. It seemed impossible.
Therefore, in the present invention, by using induction heating, fine printing with a pitch of 0.3 mm, which was conventionally difficult, can be sufficiently performed, and fine printing with a pitch of about 0.2 mm may be performed depending on conditions such as cream soldering. Can also be done.
[0031]
Further, as the induction heating condition, by supplying 1400 W of electric power for 1 to 2 seconds, the screen mask 11 can be raised to about 50 to 70 ° C. with a gap of 1 mm. Further, by setting the supplied power to about 2000 W, the same temperature rise can be achieved within one second, so that the cream solder in the through hole 11a becomes larger between the inner wall surface of the through hole 11a and the center thereof. A temperature difference can be realized. Further, by bringing the induction coil into contact with the screen mask 11, a more efficient temperature rise can be achieved.
Further, in the above-described induction heating plate separating method, the temperature difference between the inner wall surface of the through hole 11a and the central portion of the through hole 11a depends on the width of the through hole. Therefore, in a screen mask having a plurality of types of through-hole widths, the conditions may be set according to the smallest through-hole size among the plurality of through-holes to be subjected to induction heating. That is, if the minimum through-hole width is about 0.15 mm, as described above, rapid control is required such that the power supply to the induction coil is 2000 W and the supply time is about 1 second. In the case of a plurality of relatively rough through holes having a minimum through hole width of 1 mm, the supply power may be 1000 W and the supply power may be 2 to 3 seconds. Therefore, the heating condition of the induction coil can be determined in advance based on the pattern of the screen mask (in other words, the arrangement and size of the through-holes). In this case, the heating condition of the induction coil corresponding to the size of the through-hole is determined based on the pre-measured characteristic values of the cream solder (viscosity with respect to temperature, shear stress value, yield value), and separation of the plate from each through-hole. A heating condition close to the optimum characteristic value may be selected.
[0032]
It should be noted that temperature control by induction heating can also be performed when performing the mask cleaning of the screen mask 11. Thereby, the cream solder remaining in the screen mask through-hole and on the back surface can be more efficiently removed. The conditions at that time do not need to be controlled as strictly as when the plate is separated, and it is sufficient that the solder can be heated to such an extent that the fluidity of the cream solder is improved. For example, heating may be performed at 1000 W during the cleaning time.
Note that the present invention is not limited to the above embodiment, and can be implemented in other various modes.
[0033]
For example, in the above embodiment, in order to relatively separate the screen mask 11 and the substrate 14, the substrate 14 is lowered while the screen mask 11 is kept still. However. The present invention is not limited to this. The screen mask 11 may be moved while the substrate 14 is stationary, and both the screen mask 11 and the substrate 14 may be moved in a direction to separate them from each other. Good.
The printing paste is not limited to the cream solder 12, but may be any material as long as the present invention is applicable. For example, instead of cream solder, a metal powder having a fine particle diameter of about 200 μm or less and a flux may be used. Examples of the metal powder include silver and copper.
In the case of screen printing, induction heating is performed after the scraping operation of the printing paste by the squeegee. However, the invention is not limited to this, and the induction heating is started simultaneously with the scraping operation. Heating may be performed at a temperature lower than the heating temperature, and after the scraping operation is completed, the peripheral portion of the printing paste may be raised to the above-mentioned predetermined temperature by induction heating to reduce the viscosity thereof.
[0034]
In addition, the screen mask 11 is not limited to one that is uniformly induction-heated, but the induction coil 28a is partially opposed only to a portion of the circuit pattern of the cream solder 12 where the plate separation is poor, and the portion is not heated. Only the induction heating may be performed.
The present invention is not limited to the case where the induction heating is performed in a non-contact manner. The induction heating may be performed by bringing the induction heating unit 28 into contact with the upper surface of the screen mask 11 as shown in FIG. In this case, since the distance between the induction coil 28a of the induction heating unit 28 and the screen mask 11 is reduced, the induction heating can be performed efficiently and locally concentrated. In FIG. 9, reference numeral 28b denotes an induction magnetic field.
In addition, in a through-hole that is long along the direction in which the induction current of induction heating flows, the inner wall surface is easily subjected to induction heating, but the inner wall surface of the through-hole that is long in the direction orthogonal to the direction in which the induction current flows is difficult to be induction-heated Tend. Therefore, as shown in FIG. 10 (A), the through-hole 11a long along the X direction has the induction coil 28c arranged along the longitudinal direction of the through-hole 11a, and the line shown by 28c in FIG. It is preferable from the viewpoint of heat generation efficiency to generate an induced current by passing a current through the induction coil. Therefore, as shown in FIG. 10B, the induction coil 28c is also arranged along the longitudinal direction of the through hole 11a long in the Y direction, and a current is applied to the induction coil as indicated by a line 28c in FIG. 10B. It is preferable to generate the induced current by flowing. In FIG. 10B, if an induction coil is arranged in the direction of arrow 28e and a current flows through the induction coil, the inner wall surface of the through hole 11a along the Y direction does not generate much heat. In a QFP (Quad Flat Package) as shown in FIG. 10D, since the longitudinal directions of the through holes 11a on adjacent sides intersect at 45 degrees, a V-shape is formed as shown in FIG. From the viewpoint of heat generation efficiency, it is preferable to dispose an induction coil and apply an electric current to the induction coil as shown by a line 28c in FIG. 10C to generate an induction current.
[0035]
For example, as shown in FIG. 10A, a first induction coil for flowing current in the X direction and a second induction coil for flowing current in the Y direction as shown in FIG. It can also be used as a heating unit. In the induction heating unit configured by stacking two induction coils in this manner, power is alternately applied to one of the first induction coil and the second induction coil or to the first induction coil and the second induction coil. By supplying, even if the pattern of the through-holes is different, the same induction heating unit can flow a current through the induction coil only in the X-direction for the through-holes along the X-direction as shown in FIG. 10B, a current flows through the induction coil only in the Y direction for a through hole along the Y direction as shown in FIG. 10B, or an X direction and a Y direction as shown in FIGS. 10C and 10D. The current can flow through the two induction coils alternately in the X direction and the Y direction through the through holes in both directions. As a result, with respect to the through-holes of FIGS. 10C and 10D, both the through-hole 11a along the X direction and the through-hole 11a along the Y direction can be substantially uniformly induction-heated. Also, even if the patterns of the through-holes are different as shown in FIGS. 10A, 10B, 10C, and 10D, the same induction heating section allows a current to flow through the induction coil only in the X direction, or A current can be supplied to the induction coil only in the Y direction, or a current can be supplied to the induction coil alternately in the X direction and the Y direction, so that the versatility of the induction heating unit can be improved.
[0036]
FIGS. 12A and 12B show an embodiment of the present invention in which the cream solder 12 is filled by using a filling roller 100 instead of a squeegee in a screen printing method. In this embodiment, the printing material, for example, the cream solder 12 is rolled up by rotating the cylindrical filling roller 100, and the cream solder 12 is forcibly filled in the through hole 11 a of the screen mask 11. The cylindrical shape of the filling roller 100 may be a saw-shaped and spiral-shaped groove 100a shown in FIG. In FIG. 12A, reference numeral 101 denotes a scraper for scraping cream solder.
Further, in an embodiment in which the present invention is applied to a dispensing method, a nozzle 111 having a pushing function by a piston 110 as shown in FIG. 13A or a pushing function by compressed air as shown in FIG. It is also possible to forcibly fill the through hole 11a of the screen mask 11 with a printing material 112 such as cream solder. In FIG. 13B, reference numeral 112 denotes a scraper for scraping the cream solder at the tip of the nozzle 111.
[0037]
Further, the present invention is not limited to screen printing, and can be applied to other printing methods.
For example, FIG. 14 shows an embodiment in which the present invention is applied to a direct printing planographic planographic transfer printing system. Here, the printing material 122 supplied in a predetermined pattern to the planographic plate 120 is directly transferred to a predetermined position 115 of a substrate 114 as a printing medium. In FIG. 14, by inductively heating the surface of the printing material 122 that is in close contact with the lithographic plate 120, the adhesive force between the lithographic plate 120 and the printing material 122 is reduced, and transferred to a predetermined position 115 of the printing medium 114. This has the effect of making it easier.
FIGS. 15A and 15B show an embodiment in which the present invention is applied to an offset printing method. The printing material 142 is supplied from the tank 139 storing the printing material 142 to the recess 136a of the plate cylinder 136 by three rollers 140, and the printing material 142 in the recess 136a is transferred onto the blanket cylinder 137. The printing material 142 on the blanket cylinder 137 is transferred to a paper 135 as a printing medium sandwiched between the impression cylinder 138 and printing. In this embodiment, the adhesive force between the printing material 122 and the inner wall surface of the recess 136a of the plate cylinder 136 is reduced by induction heating the inner wall surface of the recess 136a where the printing material 122 is in close contact with the plate cylinder 136. In addition, there is an effect that the image can be easily transferred to the paper 135.
[0038]
FIG. 16 shows an embodiment in which the present invention is applied to a lithographic intaglio transfer printing method. In this embodiment, similarly to the screen printing method, by inductively heating the intaglio 150 and raising the temperature of the intaglio 150 itself, the shearing force of the printing material such as the cream solder 152 on the inner wall surface of the recess 150a is reduced, The effect of improving transferability to a predetermined position 155 such as a land of the substrate 154 is obtained.
FIG. 17 shows an embodiment in which the present invention is applied to an intaglio transfer printing method (gravure printing method). The printing material in the tank 165, for example, the cream solder 162, is supplied to the concave portion 163 a of the plate cylinder 163 by the supply roller 166, and the printing material 162 of the concave portion 163 a is supplied to the base material 160 sandwiched between the plate cylinder 163 and the impression cylinder 161. It is designed to be transferred and printed. In FIG. 17, reference numeral 164 denotes a doctor. The doctor 164 scrapes off an excessive amount of the printing material 162 filled in the recess 163a. In this embodiment, as in the screen printing method, the plate cylinder 163 is induction-heated to raise the temperature of the plate cylinder 163 itself, so that the shearing force of the printing material 162 on the inner wall surface of the concave portion 163a is reduced. The effect that the transfer property to the material 160 is improved is obtained.
[0039]
FIG. 23 is a perspective view of an induction coil according to another embodiment of the present invention. The induction coil is not limited to an annular coil, and may be a square frame-shaped or rectangular frame-shaped induction coil 728. Good.
FIG. 24 shows two induction coils 728 of 728a and 728b prepared in FIG. 23 and arranged on two opposite corners on the substrate on which the QFP is to be positioned. FIG. 11 is a perspective view showing a state in which an induced current 729 flows along the longitudinal direction of FIG. Preferably, the two induction coils 728a and 728b are operated simultaneously.
FIG. 25 shows four induction coils 728 of FIG. 23 of 728c, 728d, 728e, and 728f, which are respectively arranged on four corners of the substrate on which the QFP is to be positioned. It is a perspective view showing the state where induction current 729 was made to flow along the longitudinal direction. Also in this case, the four induction coils 728c to 728f are operated simultaneously.
FIG. 26 shows a case where one induction coil 728g of FIG. 23 is prepared, arranged above the portion of the substrate where the QFP is to be positioned, and one of the induction coils 728g is arranged in the arrangement direction of the through holes 11a. FIG. 11 is a perspective view showing a state where the side edges are arranged in a form inclined at 45 degrees and the same amount of induced current 729 flows through each through hole 11a.
[Brief description of the drawings]
FIGS. 1A to 1D are explanatory views for explaining a printing method according to an embodiment of the present invention; FIG.
FIG. 2 is a block diagram of a printing apparatus according to an embodiment of the present invention.
FIG. 3 is a perspective view of the printing apparatus of FIG. 2;
FIG. 4 is a flowchart of a printing operation of the printing apparatus in FIG. 2;
FIG. 5 is a cross-sectional view of a state where the screen mask is heated by the screen mask heating device of the printing apparatus.
FIG. 6 is a perspective view of an induction coil of the screen mask heating device of FIG.
FIGS. 7A to 7C are explanatory diagrams showing a graph of a viscosity distribution of a cream solder by induction heating, a graph of a temperature distribution, and a state of the cream solder in a through hole of a screen mask, respectively.
FIG. 8 is a graph showing the relationship between the temperature and the viscosity of cream solder.
FIG. 9 is a cross-sectional view of one embodiment of the present invention in which the screen mask heating device is in direct contact with the screen mask.
FIGS. 10A to 10D are explanatory views showing a state in which through-holes of a screen mask are arranged at 45 degrees along the X direction and along the Y direction, respectively, and FIGS. FIG. 2 is a perspective view of a QFP using a pattern of through holes as shown in FIG.
FIGS. 11A and 11B are a graph and a diagram illustrating a relationship between a distance from an inner wall surface of a through hole of a screen mask and a shearing force, respectively.
12A and 12B are a perspective view of a filling roller according to an embodiment of the present invention using a cylindrical filling roller instead of a squeegee, and a partial cross section of a printing state by the filling roller. FIG.
FIGS. 13A and 13B are explanatory views of an embodiment of the present invention using a pushing function by a piston instead of a squeegee, and an embodiment of the present invention using a pushing function by compressed air, respectively. It is explanatory drawing of a form.
FIG. 14 is an explanatory diagram of one embodiment of the present invention when the present invention is applied to a direct printing planographic transfer printing method.
FIGS. 15A and 15B are explanatory diagrams of an embodiment of the present invention when the present invention is applied to an offset printing method.
FIG. 16 is an explanatory diagram of an embodiment of the present invention when the present invention is applied to a planographic intaglio transfer printing method.
FIG. 17 is an explanatory diagram of an embodiment of the present invention when the present invention is applied to an intaglio transfer printing method (gravure printing method).
FIGS. 18A to 18E are explanatory diagrams each showing a conventional screen printing method.
FIGS. 19A to 19D are explanatory views showing a conventional screen printing method.
FIG. 20 is a perspective view of the X-direction drive device according to the embodiment of the present invention.
FIG. 21 is a perspective view of a plate separating device (Z-direction driving device) according to the embodiment of the present invention.
FIG. 22 is a perspective view of another plate separating device (Z-direction driving device) according to the embodiment of the present invention.
FIG. 23 is a perspective view of a rectangular induction coil according to another embodiment of the present invention.
24 is a perspective view showing a state in which two induction coils of FIG. 23 are prepared and arranged on two corners located at diagonal sides of the QFP, and an induction current flows along the longitudinal direction of each through hole. FIG.
FIG. 25 is a perspective view showing a state in which four induction coils of FIG. 23 are prepared and arranged on four corners of the QFP, and an induction current flows along the longitudinal direction of each through hole.
26 shows a case where one induction coil of FIG. 23 is prepared and arranged above the QFP, and is arranged at a 45-degree angle to the pattern of the through-holes; It is a perspective view which shows the state which made it flow.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 11 ... Screen mask, 11a ... Through-hole, 12 ... Cream solder, 12a ... Cream solder layer, 13 ... Squeegee, 14 ... Board, 15 ... Land, 20 ... Stage part, 21 ... Board loading / unloading apparatus, 22 ... Board support Device, 24: squeegee head driving device, 25: XYθ position correcting means, 26: plate separating means, 27: screen mask heating device, 28: induction heating section, 28a: induction coil, 28b: induction magnetic field, 28c: induction current, 29: timer, 30: substrate position recognition and correction unit, 31: processing operation unit, 32: recognition camera unit, 33: display unit, 34: control unit, 35: process control unit, 36: processing operation unit, 37: non-defective printing Database 38 print inspection unit 39 processing operation unit 40 print state detection unit 41 inspection reference storage unit 100 filling roller 101 Cream solder scraper, 110: piston, 111: nozzle, 112: cream solder scraper, 114: base material, 115: predetermined position, 120: planographic plate, 122: printing material, 135: paper, 136: plate Cylinder, 136a recess, 137 rubber cylinder, 138 impression cylinder, 139 tank, 140 supply roller, 142 printing material, 150 intaglio, 150a recess, 152 printing material, 154 base material, 155 Predetermined positions, 160: base material, 161: impression cylinder, 162: printing material, 163: plate cylinder, 163a: concave portion, 164: doctor, 165: tank, 166: supply roller.

Claims (17)

Holding a printing paste having the property of decreasing the viscosity with the temperature rise on the plate,
The portion of the plate where the printing paste is held is heated by electromagnetic induction heating to increase the temperature and reduce the viscosity of the printing paste in contact with the held portion to reduce the viscosity of the printing paste and the printing paste. Easy to separate,
Printing paste held on the plate is separated from the plate and printed on a printing medium,
After the printing paste is printed on the printing medium, a printing state is detected, and printing for controlling the electromagnetic induction heating condition of the plate or the separation condition between the printing plate and the printing medium based on the detection result is performed. Method. The printing plate has an opening having a predetermined pattern for holding the printing paste, and after the printing plate comes into contact with the printing medium, the printing plate and the printing medium are relatively separated from each other to form an opening in the opening. The printing method according to claim 1, wherein the printing paste is printed on the printing medium. The printing method according to claim 2, wherein the electromagnetic induction heating device that performs the electromagnetic induction heating performs the electromagnetic induction heating on the plate in a non-contact manner. 4. The printing method according to claim 3, wherein a distance between the electromagnetic induction heating device and the printing plate is set to a size such that a predetermined induction current flows through the printing plate by the electromagnetic induction heating device. The printing method according to claim 2, wherein the electromagnetic induction heating device that performs the electromagnetic induction heating contacts the plate to perform the electromagnetic induction heating. The printing method according to any one of claims 2 to 5, wherein the electromagnetic induction heating is performed after holding of the printing paste in the opening of the plate is completed. 7. The printing method according to claim 2, wherein the opening is a through hole, and the printing plate is a screen mask, and the printing paste is filled in the through hole by moving a squeegee. By the electromagnetic induction heating, the printing paste has a temperature gradient such that the temperature of the portion in contact with the portion held by the plate is high, and the temperature gradually decreases as the distance from the portion increases. Item 8. The printing method according to any one of Items 2 to 7. The printing method according to any one of claims 2 to 8, wherein the induction current for generating the electromagnetic induction heating flows along a longitudinal direction of the opening of the plate. The printing paste is supplied into the opening of the printing plate by placing the printing plate on the printing medium and bringing the printing paste into contact with the printing plate, supplying the printing paste to the printing plate, and moving the printing paste in one direction from one end of the printing plate with a squeegee. Filling and removing the plate from the printing medium, a printing apparatus that moves the printing paste in the opening of the plate onto the printing medium to form a printing paste layer on the printing medium. ,
A plate having an opening of a predetermined pattern for holding a printing paste having a property of decreasing viscosity with increasing temperature,
The temperature of the portion where the printing paste is held in the plate is increased by electromagnetic induction heating to reduce the viscosity of the printing paste that comes into contact with the held portion and facilitate separation of the printing paste from the plate. An electromagnetic induction heating device,
After the printing plate comes into contact with the printing medium, the printing plate and the printing medium are relatively separated from each other, and the printing paste held in the opening of the printing plate is separated from the printing plate and printed on the printing medium. Printing paste separating device,
After the printing paste is printed on the printing medium, a printing state is detected, and control for controlling conditions of the electromagnetic induction heating of the plate or separation conditions of the printing plate and the printing medium based on the detection result is performed. And a printing device. The printing apparatus according to claim 10 , wherein the electromagnetic induction heating device that performs the electromagnetic induction heating performs the electromagnetic induction heating on the plate in a non-contact manner. 12. The printing apparatus according to claim 11 , wherein a distance between the electromagnetic induction heating device and the printing plate is set to a size such that a predetermined induction current flows through the printing plate by the electromagnetic induction heating device. The printing apparatus according to claim 10 , wherein the electromagnetic induction heating device that performs the electromagnetic induction heating contacts the plate to perform the electromagnetic induction heating. The printing apparatus according to any one of claims 10 to 13 , wherein the electromagnetic induction heating is performed after the holding of the printing paste in the opening of the plate is completed. The opening is a through hole, the plate is printing apparatus according to any one of claims 10 to 14 for the printing paste by the movement of the squeegee a screen mask so as to fill in the through hole. By the electromagnetic induction heating, the printing paste has a temperature gradient such that the temperature of the portion in contact with the portion held by the plate is high, and the temperature gradually decreases as the distance from the portion increases. Item 16. The printing device according to any one of Items 10 to 15 . The printing apparatus according to any one of claims 10 to 16 , wherein the induction current for generating the electromagnetic induction heating flows along the longitudinal direction of the opening of the plate.

Images