JP6630919B2 - Screen printing apparatus and screen printing method - Google Patents

Description

  The present invention relates to a screen printing device and a screen printing method.

  2. Description of the Related Art A screen printing apparatus has been widely used as an apparatus for printing a paste such as solder on a pattern to be printed (a combination of electrode patterns of individual substrates) of a printing object, which is one or a plurality of aligned substrates. ing. When printing a paste on a print target pattern of a printing target by a screen printing apparatus, a mask having an opening pattern corresponding to the print target pattern is prepared in advance. Then, the printed object conveyed is brought into contact with the lower surface of the mask, the paste is pressed into the opening pattern, and then the printed object is separated from the mask (plate separation). Thereby, the paste is deposited on the pattern to be printed corresponding to the opening pattern.

  In such a screen printing apparatus, the printing target and the mask need to be brought into contact with each other with high accuracy so that the pattern to be printed and the opening pattern are vertically overlapped. For this reason, a mark (mask-side mark) is provided on the mask, and a mark (substrate-side mark) is also provided on the substrate constituting the printing object, and the mask-side mark and the substrate-side mark are aligned, and The printing object and the mask are brought into contact. Here, when the substrate to be printed has an in-plane expansion / contraction deformation, for example, because the substrate is a film-shaped substrate, the pattern to be printed and the opening pattern do not completely overlap with each other, but the displacement between the two does not occur. The printing target pattern and the opening pattern are overlapped as a whole (in an average sense) with an accuracy within an allowable range. Patent Document 1 below discloses a technique in which three or more marks provided on a substrate are respectively imaged so that a shift between a pattern to be printed and an opening pattern can be accurately recognized.

Japanese Patent No. 4619896

  However, in the above-described conventional screen printing apparatus, when the degree of expansion and contraction deformation of the printing target is large, even if the deviation between the printing pattern and the opening pattern is accurately recognized, the printing pattern and the opening pattern are Cannot be superimposed with an accuracy within an allowable range, and there is a problem that the printing failure of the paste on the printing target may occur.

  Therefore, an object of the present invention is to provide a screen printing apparatus and a screen printing method in which printing failure is unlikely to occur even when the degree of expansion and contraction of a printing object is large.

The screen printing apparatus of the present invention is a screen printing apparatus that prints a paste on a pattern to be printed on a printing object, which is a plurality of substrates, and a mask provided with a plurality of opening patterns having different sizes, and a mask below the mask. A transport unit that transports the printing target, an imaging unit that captures a pair of substrate-side marks of one of the plurality of substrates that constitute the printing target, and an imaging unit that captures the mark. A deformation degree calculating unit that calculates a degree of expansion and contraction deformation of the printing target based on a ratio of the obtained measured value of the distance between the pair of substrate side marks and a design value of the distance between the pair of substrate side marks. A selecting unit that selects one opening pattern from the plurality of opening patterns based on a degree of expansion and contraction deformation of the printing target object calculated by the deformation degree calculating unit; A contact mechanism for contacting the printing object and the mask conveyed below the mask, the contact mechanism so that the opening pattern selected by the selection unit and the pattern to be printed overlap. The mask and the substrate are relatively moved.

The screen printing method of the present invention is a screen printing method for printing a paste on a pattern to be printed on a printing target, which is a plurality of substrates, wherein the printing target is provided below a mask provided with a plurality of opening patterns having different sizes. A transporting step of transporting an object, an imaging step of imaging a pair of substrate-side marks of one of the plurality of substrates constituting the printing target, and the imaging step obtained by the imaging in the imaging step. A deformation degree calculating step of calculating a degree of expansion and contraction deformation of the printing object based on a ratio between an actually measured value of the distance between the pair of substrate side marks and a design value of the distance between the pair of substrate side marks; A selection step of selecting one opening pattern from the plurality of opening patterns based on the degree of expansion / contraction of the printing object calculated in the calculation step; A contact step of contacting the mask with the object to be printed conveyed below a mask, wherein the mask and the mask are contacted in the contacting step so that the opening pattern selected in the selecting step and the pattern to be printed overlap. The substrate is relatively moved.

  ADVANTAGE OF THE INVENTION According to this invention, even if the degree of expansion-contraction deformation of a printing target is large, printing failure does not easily occur.

FIG. 1 is a plan view of a screen printing apparatus according to an embodiment of the present invention. FIG. 2 is a plan view of an operation target input in the screen printing apparatus according to the embodiment of the present invention. (A) Plan view (b) Front view of the screen printing apparatus in one embodiment of the present invention FIG. 1 is a side view of a screen printing apparatus according to an embodiment of the present invention. FIG. 1 is a plan view of a mask included in a screen printing apparatus according to an embodiment of the present invention. (A) (b) (c) Side view of a part of the screen printing apparatus in one embodiment of the present invention. 1 is a block diagram illustrating a control system of a screen printing apparatus according to an embodiment of the present invention. (A) (b) Operation explanatory view of the screen printing apparatus in one embodiment of the present invention (A) (b) Operation explanatory view of the screen printing apparatus in one embodiment of the present invention

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 shows a screen printing apparatus 1 according to an embodiment of the present invention. The screen printing apparatus 1 is an apparatus that screen-prints a paste such as solder on a print pattern 3P (FIG. 2) of a print target 3 which is one or a plurality of aligned substrates 2. Here, the term “a plurality of aligned substrates 2” refers to a substrate in which a plurality of substrates 2 are manufactured from one base substrate and are connected to each other in a screen printing stage, or a plurality of independently manufactured substrates. Reference numeral 2 denotes a substrate or the like that is mounted in a predetermined position on the carrier. In the present embodiment, as shown in FIG. 2, two substrates 2 aligned and attached to the carrier 4 are used as the print target 3, and the entirety including the two substrates 2 and the carrier 4 is referred to as a work target 5. explain. The “pattern 3P to be printed on the printing object 3” refers to a combination of the electrode patterns 2P of the individual substrates 2 constituting the printing object 3 (FIG. 2). The substrate 2 is assumed to be a film-like substrate.

  1, 3A, 3B, and 4, the screen printing apparatus 1 includes a loading unit 12, a target holding and moving mechanism 13, and a discharging unit 14 on a base 11. A pair of beam members 15 are provided at both ends in the left-right direction (X-axis direction) of the base 11 as viewed from the operator OP, and extend in the front-rear direction (Y-axis direction) as viewed from the operator OP. Have been. A mask 16 is installed between the pair of beam members 15 in a horizontal posture. The pair of beam members 15 are provided with a squeegee unit 17 that moves above the mask 16 and an imaging unit 18 that moves below the mask 16.

  The loading unit 12, the target holding and moving mechanism 13, and the unloading unit 14 are provided in this order from the left as viewed from the operator OP. The carry-in section 12 is composed of a pair of conveyors, and carries in the work object 5 supplied from outside (that is, the print object 3). The target holding / moving mechanism 13 receives and holds the work target 5 from the loading unit 12, and transfers the work target 5 to the discharge unit 14 when the screen printing on the print target 3 is completed. The unloading section 14 is composed of a pair of conveyors, and unloads the work target 5 received from the target holding and moving mechanism 13 to the outside.

  In FIG. 4, the target holding / moving mechanism 13 includes a target holding unit 21 and a moving mechanism unit 22 for moving the target holding unit 21 in a horizontal plane direction and in a vertical direction. The target holding unit 21 includes a transport unit 31, a lower receiving member 32, and a pair of clampers 33 (see also FIGS. 3A and 3B).

  The transport unit 31 includes a pair of conveyors, transports the work object 5 received from the loading unit 12 in the X-axis direction, and positions the work target 5 at a predetermined clamp position below the mask 16. The lower receiving member 32 supports the lower surface of the work target 5 positioned at the clamp position by the transport unit 31. The pair of clampers 33 clamp and hold the work object 5 supported by the lower receiving member 32 in the Y-axis direction. In the present embodiment, of the pair of clampers 33, the one located on the side (front) of the worker OP is referred to as the front clamper 33F, and the one located on the side (rear) opposite to the worker OP is the rear clamper. 33R (FIGS. 3A and 4).

  In FIG. 5, the mask 16 has a rectangular flat plate shape extending and extending in the XY plane. The outer periphery of the mask 16 is supported by a frame member 16w. The mask 16 is provided with three (three types) opening patterns 40 corresponding to the pattern to be printed 3P. The three opening patterns 40 are similar to each other and have different sizes, and are provided side by side in the Y-axis direction.

  In FIG. 5, the three opening patterns 40 include a central opening pattern 41, a front opening pattern 42, and a rear opening pattern 43. The center opening pattern 41 is formed at the center of the mask 16 in the Y-axis direction. The front opening pattern 42 is formed in front of the mask 16, and the rear opening pattern 43 is formed behind the mask 16.

  The central opening pattern 41 is provided in a size corresponding to the pattern to be printed 3P when the printing object 3 has not undergone in-plane expansion and contraction deformation. The front opening pattern 42 is provided in a size corresponding to the pattern 3P to be printed when the printing object 3 has undergone in-plane extension deformation. The rear opening pattern 43 is provided in a size corresponding to the pattern to be printed 3P when the printing object 3 has undergone in-plane contraction deformation. Assuming that the enlargement ratio of the size of the central opening pattern 41 (the sign is H) is H = 1, the enlargement ratio H of the front opening pattern 42 is H> 1, and the enlargement ratio H of the rear opening pattern 43 is H <1. is there. In the present embodiment, it is assumed that the enlargement ratio of the front opening pattern 42 is H = 1.1, and the enlargement ratio H of the rear opening pattern 43 is H = 0.9. It should be noted that the enlargement ratio is not limited to the above numerical value, but is determined by the material of the substrate 2 or a numerical value selected by an operator.

  The movement mechanism unit 22 moves the target holding unit 21 to a position below the central opening pattern 41 (referred to as a first position), a position below the front opening pattern 42 (referred to as a second position), and a rear opening position. It is selectively located at one of the positions below the pattern 43 (referred to as a third position). The carry-in part 12 and the carry-out part 14 form a transport path for the work target 5 that is continuous in the X direction with the transport part 31 of the target holding part 21 located at the first position (FIG. 3A).

  In FIG. 2, each of the two substrates 2 is provided with a pair (two) of substrate-side marks 2m. On the other hand, four mask-side marks 16m corresponding to the four substrate-side marks 2m provided on the two substrates 2 (that is, the print target 5) are provided in the vicinity of each opening pattern 40 of the mask 16 (FIG. 1). 5).

  The moving mechanism unit 22 moves the target holding unit 21 to one of the first position, the second position, and the third position, and then raises the target holding unit 21 (that is, the work target 5). The upper surface of the printing target 3 can be brought into contact with the lower surface of the mask 16. In a state where the upper surface of the printing target 3 is in contact with the lower surface of the mask 16, the upper surfaces of the pair of clampers 33 that clamp the printing target 3 also contact the lower surface of the mask 16.

  FIG. 6A illustrates a state in which the moving mechanism unit 22 raises the target holding unit 21 from the first position and causes the upper surface of the printing target 3 to contact the lower surface of the mask 16. In this state, the pattern 3P to be printed overlaps the central opening pattern 41, the front clamper 33F abuts on the lower surface of the mask 16 in front of the central opening pattern 41 (the rear area of the front opening pattern 42), and the rear clamper 33R is in contact with the mask 16 In contact with the rear area of the central opening pattern 41 on the lower surface of.

  FIG. 6B illustrates a state in which the moving mechanism unit 22 raises the target holding unit 21 from the second position to bring the upper surface of the printing target 3 into contact with the lower surface of the mask 16. In this state, the pattern 3P to be printed overlaps the front opening pattern 42, the front clamper 33F contacts the front area of the front opening pattern 42 on the lower surface of the mask 16, and the rear clamper 33R is behind the front opening pattern 42 on the lower surface of the mask 16. It contacts the area (the area in front of the central opening pattern 41).

  FIG. 6C illustrates a state in which the moving mechanism unit 22 raises the target holding unit 21 from the third position and brings the upper surface of the printing target 3 into contact with the lower surface of the mask 16. In this state, the pattern to be printed 3P and the rear opening pattern 43 overlap, the front clamper 33F contacts the front area of the rear opening pattern 43 on the lower surface of the mask 16 (the rear area of the central opening pattern 41), and the rear clamper 33R In contact with the rear area of the rear opening pattern 43 on the lower surface of the substrate.

  In the present embodiment, when the pattern to be printed 3P and the front opening pattern 42 are overlapped with the area where the upper surface of the front clamper 33F contacts the lower surface of the mask 16 when the pattern to be printed 3P and the center opening pattern 41 are overlapped. The area where the upper surface of the rear clamper 33R contacts the lower surface of the mask 16 is the same (FIGS. 6A and 6B). Further, when the printed pattern 3P and the central opening pattern 41 overlap, the upper surface of the rear clamper 33R contacts the lower surface of the mask 16, and when the printed pattern 3P and the rear opening pattern 43 overlap each other, the front clamper 33F The area where the upper surface contacts the lower surface of the mask 16 is the same (FIGS. 6A and 6C).

  In FIGS. 5 and 6A, a certain area in front of the central opening pattern 41 (a certain area behind the front opening pattern 42) in the area on the upper surface of the mask 16 is a front paste supply area E1, and A certain area behind the opening pattern 43 is a rear paste supply area E2. The paste Pst is supplied to both the front paste supply area E1 and the rear paste supply area E2 in advance.

  3A, 3B, and 4, the squeegee unit 17 includes a squeegee base 51 that extends in the X-axis direction and has both ends supported on upper surfaces of a pair of beam members 15. Two squeegee elevating cylinders 52 are arranged side by side in the Y-axis direction at the center in the X-axis direction on the upper surface side of the squeegee base 51, and two squeegees 53 are arranged below the two squeegee elevating cylinders 52. ing. The two squeegees 53 are respectively connected to the squeegee elevating cylinders 52. When the two squeegee elevating cylinders 52 are individually operated, the two squeegees 53 are independently raised and lowered below the squeegee base 51 in response thereto.

  Each of the two squeegees 53 extends in the X-axis direction, and two surfaces opposed to each other in the Y-axis direction serve as a scraping surface of the paste Pst. In the present embodiment, of the two squeegees 53 provided side by side in the Y-axis direction, the one located at the front (right side in FIG. 4) is referred to as front squeegee 53F, and the one located behind (left side in FIG. 4). The one located is referred to as a rear squeegee 53R. The squeegee base 51 is driven by a squeegee base driving mechanism 15A (FIG. 3A) provided on the pair of beam members 15 and moves in the Y-axis direction, whereby the two squeegees 53 move above the mask 16 in the Y-axis direction. Move in the direction.

  3A, 3B and 4, both ends of an X-axis beam 61 extending in the X-axis direction are attached to the lower surfaces of the pair of beam members 15. A moving plate 62 is provided on the X-axis beam 61, and the imaging unit 18 is attached to the moving plate 62. The imaging unit 18 includes a lower imaging camera 71 whose imaging field of view is directed downward, and an upper imaging camera 72 whose imaging field of view is directed upward (FIG. 4).

  The X-axis beam 61 is driven by an X-axis beam driving mechanism 15B (FIG. 3A) provided on the pair of beam members 15, and moves in the Y-axis direction. The moving plate 62 is driven by a moving plate driving mechanism 61M (FIG. 3A) provided on the X-axis beam 61 and moves in the X-axis direction. Therefore, the imaging unit 18 moves the X-axis beam 61 with respect to the pair of beam members 15 in the Y-axis direction by the X-axis beam driving mechanism 15B, and moves the X-axis of the moving plate 62 with respect to the X-axis beam 61 by the moving plate driving mechanism 61M. With the movement in the direction, the mask 16 is moved horizontally below the mask 16.

  In FIG. 7, the control device 80 included in the screen printing apparatus 1 is configured to carry in the work target 5 by the carry-in unit 12, transport the work target 5 by the transport unit 31 of the target holding unit 21, and hold and move the work target 5 by the clamper 33. The operation of the movement of the object holding unit 21 by the mechanism unit 22 and the operation of unloading the work target 5 by the unloading unit 14 are controlled. The control device 80 also controls the movement of the squeegee base 51 by the squeegee base driving mechanism 15A, the lifting and lowering of the squeegee 53 by the squeegee lifting cylinder 52, and the movement of the imaging unit 18 by the X-axis beam driving mechanism 15B and the moving plate driving mechanism 61M. Do.

  In FIG. 7, the control device 80 controls each of the imaging by the lower imaging camera 71 and the imaging by the upper imaging camera 72. Image information obtained by imaging by the lower imaging camera 71 and image information obtained by imaging by the upper imaging camera 72 are respectively input to the control device 80. Further, an input / output device 81 such as a touch panel is connected to the control device 80. The operator OP inputs necessary information to the screen printing apparatus 1 through the input / output device 81, and obtains various information about the screen printing apparatus 1 through the input / output device 81.

  Next, an execution procedure of the screen printing operation by the screen printing apparatus 1 will be described. When the work object 5 is supplied to the carry-in unit 12 of the screen printing apparatus 1, the carry-in unit 12 carries in the work object 5, and transfers the work object 5 to the transport unit 31 of the object holding unit 21 previously positioned at the first position. Hand over. The transport unit 31 transports the work target 5 to a clamp position below the mask 16 (transport step). When the transport unit 31 transports the work target 5 below the mask 16, the lower receiving member 32 rises to support the lower surface of the work target 5 located at the clamp position, and the pair of clampers 33 clamp the work target 5. (FIG. 8A, arrow A shown in the figure).

  When the pair of clampers 33 hold the work target 5, the X-axis beam driving mechanism 15B and the moving plate driving mechanism 61M operate in conjunction to move the imaging unit 18 to cause the lower imaging camera 71 to image the substrate side mark 2m (imaging). Process). At this time, the lower imaging camera 71 captures an image of the substrate-side mark 2m corresponding to one predetermined substrate 2 among the two substrates 2 forming the printing target 3. Image information of the board side mark 2m captured by the lower imaging camera 71 is sent to the control device 80.

  When the image information of the board side mark 2m is sent from the lower imaging camera 71, the control device 80 causes the deformation degree calculator 80a (FIG. 7) to set the substrate side of the one substrate 2 sent from the lower imaging camera 71 The degree of deformation of the printing target 3 is calculated based on the imaging result of the mark 2m (that is, the imaging result by the imaging unit 18) (a deformation degree calculating step). Here, the “degree of deformation of the printing target 3” refers to a deviation between a design value and a measured value with respect to the mounting surface of the printing target 3, and the surface area of the printing target 3 is larger than the design value or It refers to the degree of reduced deformation. The deviation between the design value and the actually measured value with respect to the mounting surface of the printing target 3 is determined from a specific side, a diagonal line, a surface area, and the like. The degree of deformation includes the case where the printing target 3 is warped and the surface area is reduced on the captured image.

  In the calculation of the degree of deformation of the print target 3, the control device 80 first determines a pair of pairs of the substrate 2 based on the image recognition result of the substrate side mark 2 m of one substrate 2 sent from the lower imaging camera 71. The distance between the substrate side marks 2m (actually measured value M) is calculated. Then, the ratio of the calculated actual measurement value M to the design value L of the distance between the pair of substrate-side marks 2m is defined as the degree of deformation P (= M / L) of the printing object 3.

  As described above, in the present embodiment, the imaging unit 18 captures an image of the pair of substrate-side marks 2 m of one substrate 2, and the deformation degree calculation unit 80 a outputs the pair of substrate-side marks obtained by the imaging of the imaging unit 18. The degree of expansion and contraction of the print target 3 is calculated based on the distance of 2 m. Note that the calculation method of the degree of deformation P shown here is merely an example, and another calculation method may be used.

  When the imaging unit 18 captures an image of the substrate-side mark 2m of one substrate 2, if the measured value M of the substrate 2 is equal to the design value L, the degree of deformation P becomes P = 1, but the substrate 2 is extended. When the measured value M exceeds the design value L, the degree of deformation P is P> 1. When each substrate 2 is reduced and the measured value M is smaller than the design value L, the deformation degree P is P <1.

  After the deformation degree calculating unit 80a calculates the deformation degree P of the printing target 3, the selecting unit 80b (FIG. 7) of the control device 80 provides the mask 16 based on the deformation degree P calculated by the deformation degree calculating unit 80a. One of the three opening patterns 40 (central opening pattern 41, front opening pattern 42, and rear opening pattern 43) is selected (selection step). The selection unit 80b selects based on which of the three opening patterns 40 provided in the mask 16 the printing pattern 3P of the printing target 3 is brought into contact with the print pattern 3P to minimize the printing deviation.

  A selection criterion for selecting the opening pattern 40 by the selection unit 80b can be determined in advance. In the present embodiment, a region of the degree of deformation based on the enlargement ratio (H = 1.0) of the center opening pattern 41 (a first degree of deformation region; for example, 0.95 ≦ P ≦ 1.05), Deformation area (second deformation degree area; for example, 1.05 <P <1.15) based on the enlargement ratio (H = 1.1) of front opening pattern 42 and enlargement of rear opening pattern 43 An area of the degree of deformation based on the ratio (H = 0.9) (third degree of deformation area, for example, 0.85 <P <0.95) is defined. Then, the selection unit 80b selects the opening pattern 40 according to which of the three deformation degree regions the value of the deformation degree P calculated by the deformation degree calculation unit 80a belongs to.

  In the above example, when the calculated deformation degree P of the printing target 3 is, for example, P = 1.02, the selection unit 80b determines that the value of the deformation degree P belongs to the first deformation degree area. Therefore, the opening pattern 40 with the enlargement ratio H = 1.0, that is, the center opening pattern 41 is selected. When the calculated degree of deformation P of the print target 3 is, for example, P = 1.12, the selecting unit 80b determines that the enlargement ratio is high because the degree of deformation P belongs to the second degree of deformation area. H selects the opening pattern 40 where H = 1.1, that is, the front opening pattern 42. When the calculated deformation degree P of the printing target 3 is, for example, P = 0.92, the selection unit 80b determines that the enlargement ratio H is high because the deformation degree P belongs to the third deformation degree area. Selects the opening pattern 40 of H = 0.9, that is, the rear opening pattern 43. If the calculated degree of deformation P of the print target 3 does not belong to any of the first to third deformation degree regions, the selecting unit 80b causes the print target 3 to have an abnormal deformation. And an error is determined.

  After selecting the opening pattern 40 as described above, the control device 80 causes the moving mechanism unit 22 to move the target holding unit 21 so that the work target 5 is located below the selected opening pattern 40. Specifically, when the center opening pattern 41 is selected, the target holding unit 21 is positioned at the first position, and when the front opening pattern 42 is selected, the target holding unit 21 is positioned at the second position. When the rear opening pattern 43 is selected, the target holding unit 21 is positioned at the third position.

  When the target holding unit 21 is positioned below the selected opening pattern 40, the X-axis beam driving mechanism 15B and the moving plate driving mechanism 61M operate in conjunction to move the imaging unit 18, and the upper imaging camera 72 sets the mask side mark 16m. Is imaged. Here, the mask-side marks 16m captured by the upper imaging camera 72 are a plurality of mask-side marks 16m (FIG. 5) corresponding to the selected opening pattern 40. More specifically, when the center opening pattern 41 is selected, four mask-side marks 16m corresponding to the center opening pattern 41 are imaged, and when the front opening pattern 42 is selected, the four mask-side marks 16m are selected. The four mask side marks 16m corresponding to the rear opening pattern 43 are selected, and when the rear opening pattern 43 is selected, the four mask side marks 16m corresponding to the rear opening pattern 43 are imaged. Image information of the mask-side mark 16m captured by the upper imaging camera 72 is sent to the control device 80.

  When the upper imaging camera 72 images the mask-side mark 16m, the X-axis beam driving mechanism 15B and the moving plate driving mechanism 61M operate in conjunction with each other to move the imaging unit 18 and cause the lower imaging camera 71 to image the substrate-side mark 2m. At this time, the board-side mark 2m imaged by the lower imaging camera 71 is the board-side mark 2m of each of the boards 2 constituting the printing target 3.

  When the lower imaging camera 71 images the substrate-side mark 2m of each substrate 2 constituting the print target 3, the control device 80 determines the position of each mask-side mark 16m and the position of each substrate-side mark 2m based on the imaging result. Then, the target holding unit 21 is moved in the horizontal plane direction by the movement mechanism unit 22 so that the plurality of mask-side marks 16m and the plurality of substrate-side marks 2m match in plan view. At this time, unless the size of the pattern to be printed 3P corresponds to one of the sizes of the three opening patterns 40, the plurality of mask-side marks 16m and the plurality of substrate-side marks 2m completely match in plan view. However, it is only necessary that the plurality of mask-side marks 16m and the plurality of substrate-side marks 2m match as a whole (in an average sense).

  When the plurality of mask-side marks 16m and the plurality of substrate-side marks 2m match in plan view as described above, the control device 80 operates the moving mechanism unit 22 to raise the target holding unit 21 ( 8B, the printing object 3 is brought into contact with the lower surface of the mask 16 (FIG. 8B, contact step). As a result, the selected opening pattern 40 and the pattern to be printed 3P are overlaid. In this contact step, the moving mechanism section 22 functions as a contact mechanism for bringing the printing target 3 into contact with the mask 16.

  The screen printing apparatus 1 according to the present embodiment has the mask 16 provided with a plurality of opening patterns 40 which are similar to each other and have different sizes, and the degree of deformation (the degree of deformation P) of the printing target 3 is calculated. One of the opening patterns 40 selected from the plurality of opening patterns 40 based on the printing pattern 3P is overlapped. Therefore, even when the degree of expansion and contraction of the printing target 3 is large, the probability that the printing target pattern 3P can be overlapped with one of the plurality of opening patterns 40 with an accuracy within an allowable range in the contact step. Will be higher.

  When the printing object 3 is brought into contact with the mask 16, the control device 80 deposits the paste Pst on the pattern to be printed 3P via the mask 16 that has been brought into contact with the printing object 3 (printing step). In this printing step, first, the squeegee elevating cylinder 52 is operated to lower one of the two squeegees 53 provided in the squeegee unit 17 with respect to the squeegee base 51, and the lower end of the squeegee 53 is brought into contact with the mask 16. Then, the squeegee base driving mechanism 15A moves the squeegee base 51 in the Y-axis direction, and slides the squeegee 53 on the opening pattern 40 (the selected opening pattern 40) of the mask 16 that is in contact with the printing object 3. . Thereby, the squeegee 53 scrapes the paste Pst supplied to the front paste supply area E1 or the rear paste supply area E2 on the mask 16 and fills the opening pattern 40 with the paste Pst.

  In filling the paste Pst into the central opening pattern 41, first, the front squeegee 53F moves backward from the front paste supply area E1 and slides on the central opening pattern 41 (arrow C1 shown in FIG. 9A). Then, the paste Pst on the front paste supply area E1 is raked up to the area behind the central opening pattern 41. Then, this time, the rear squeegee 53R moves forward from the rear area of the central opening pattern 41 and slides on the central opening pattern 41 (arrow C2 shown in FIG. 9B), and the paste Pst is transferred to the front paste supply area. Raise to E1.

  In filling the paste Pst into the front opening pattern 42, first, the rear squeegee 53R moves forward from the front paste supply area E1 and slides on the front opening pattern 42 (arrow C2 shown in FIG. 9B). Then, the paste Pst on the front paste supply area E1 is raked up to the front area of the front opening pattern 42. Then, this time, the front squeegee 53F moves backward from the front area of the front opening pattern 42 and slides on the front opening pattern 42 (arrow C1 shown in FIG. 9A), and transfers the paste Pst to the front paste supply area. Raise to E1.

  In filling the paste Pst into the rear opening pattern 43, first, the front squeegee 53F moves rearward from the rear paste supply area E2 and slides on the rear opening pattern 43 (arrow C1 shown in FIG. 9A). Then, the paste Pst on the rear paste supply area E2 is scraped to the rear area of the rear opening pattern 43. Then, the rear squeegee 53R moves forward from the rear area of the rear opening pattern 43 and slides on the rear opening pattern 43 (arrow C2 shown in FIG. 9B), and the paste Pst is moved to the rear paste supply area. Scratch to E2.

  When the paste Pst is filled in the opening pattern 40 as described above, the paste Pst is deposited on the pattern to be printed 3P, and the printing process ends. In this printing process, the squeegee unit 17 functions as a printing unit that deposits the paste Pst on the pattern to be printed 3P via the mask 16 that is in contact with the printing target 3.

  When the printing process is completed, the moving mechanism unit 22 operates to lower the target holding unit 21 to separate the work target 5 (that is, the print target object 3) from the mask 16 (plate separation). Then, after the pair of clampers 33 are opened and the holding of the work object 5 is released, the transport unit 31 and the unloading unit 14 operate in conjunction with each other, and unload the work object 5 to the downstream process side.

  As described above, the screen printing apparatus 1 (screen printing method) according to the present embodiment includes the mask 16 provided with the plurality of opening patterns 40 that are similar to each other and have different sizes. One of the opening patterns 40 selected from the plurality of opening patterns 40 based on the degree of deformation (the degree of deformation P) and the pattern to be printed 3P overlap each other. Even in the case of a large size, the probability that the pattern 3P to be printed can be overlapped with one of the plurality of opening patterns 40 with an accuracy within an allowable range is high, and printing failure is unlikely to occur.

  Although the embodiments of the present invention have been described, the present invention is not limited to the above-described embodiments. For example, in the above-described embodiment, the number of the substrates 2 attached to the carrier 4 is two, but this is an example, and any number of substrates including one may be used. In the above-described embodiment, three opening patterns 40 (central opening pattern 41, front opening pattern 42, and rear opening pattern 43) having a similar size and different sizes are provided, but this is an example. The number of the opening patterns 40 provided in the mask 16 may be any number as long as it is plural.

  In the above-described embodiment, the plurality of opening patterns 40 are provided in a size corresponding to the pattern to be printed 3P when the printing target 3 has not undergone in-plane expansion / contraction deformation (enlargement ratio H = 1). And one provided at a size corresponding to the pattern to be printed 3P when the print object 3 has undergone in-plane elongation deformation (having an enlargement ratio H> 0), and One combination (enlargement ratio H <0) provided in a size corresponding to the pattern to be printed 3P when the target object 3 has undergone in-plane contraction deformation, but this is merely an example. The plurality of opening patterns 40 can be combined in various sizes.

  Further, in the above-described embodiment, in the contact mechanism (or contact step) for bringing the print target 3 into contact with the mask 16, the print target 3 is moved with respect to the mask 16 so that the print target 3 and the mask 16 are moved. However, the mask 16 may be moved with respect to the printing target 3 so that the printing target 3 and the mask 16 are in contact with each other. That is, in the above-described embodiment, the target holding unit 21 is moved to the moving mechanism unit 22 so that the printing target 3 is located below the selected opening pattern 40, but the mask 16 is moved in the horizontal direction. A mask moving mechanism may be further provided to move the mask 16 so that the printing target 3 is located below the selected opening pattern 40. Further, when the printing object 3 is selected in advance by the operator OP according to the degree of deformation, the degree of deformation or the opening pattern 40 to be selected may be input to the input / output device 81 to omit the above-described imaging step. .

  Provided are a screen printing apparatus and a screen printing method in which printing failure is unlikely to occur even when the degree of expansion and contraction of a printing target is large.

DESCRIPTION OF SYMBOLS 1 Screen printing apparatus 2 Substrate 3 Printed object 3P Printed pattern 16 Mask 18 Imaging part 22 Moving mechanism part (contact mechanism)
31 transport section 40 opening pattern 80a deformation degree calculating section 80b selecting section Pst paste

Claims (4)

A screen printing apparatus that prints a paste on a pattern to be printed on a printing object that is a plurality of substrates,
A mask provided with a plurality of opening patterns having different sizes,
A transport unit that transports the print target below the mask,
An imaging unit configured to image a pair of substrate-side marks included in one of the plurality of substrates constituting the printing target,
Based on the ratio between the measured value of the distance between the pair of substrate-side marks obtained by the imaging of the imaging unit and the design value of the distance between the pair of substrate-side marks, the degree of expansion and contraction of the print target is determined. A deformation degree calculating unit for calculating,
A selection unit that selects one opening pattern from the plurality of opening patterns based on a degree of expansion and contraction deformation of the printing target object calculated by the deformation degree calculation unit;
A contact mechanism for bringing the printing object and the mask conveyed below the mask by the conveyance unit into contact with each other,
A screen printing apparatus, wherein the mask and the substrate are relatively moved by the contact mechanism so that the opening pattern selected by the selection unit and the pattern to be printed overlap.   The screen printing apparatus according to claim 1, wherein the substrate is a film-shaped substrate.   The screen printing apparatus according to claim 1, wherein the plurality of opening patterns having different sizes are similar to each other. A screen printing method for printing a paste on a pattern to be printed on a printing object, which is a plurality of substrates,
A conveyance step of conveying the printing target below a mask provided with a plurality of opening patterns having different sizes,
An imaging step of imaging a pair of substrate-side marks included in one of the plurality of substrates constituting the printing target,
Based on the ratio between the measured value of the distance between the pair of substrate-side marks obtained by the imaging in the imaging step and the design value of the distance between the pair of substrate-side marks, the degree of expansion and contraction of the print target is determined. Calculating the degree of deformation,
A selecting step of selecting one opening pattern from the plurality of opening patterns based on a degree of expansion and contraction deformation of the printing target object calculated in the deformation degree calculating step;
A contact step of contacting the mask with the print target transferred below the mask in the transfer step,
A screen printing method, wherein the mask and the substrate are relatively moved in the contacting step so that the opening pattern selected in the selecting step and the pattern to be printed overlap.

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