JP2014200935A - Screen printer and screen printing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a screen printer and a screen printing method that can form a flat printed surface on a printed object with a dent part and transcribe clearly a shape of a non-opening part on a part of the flat printed surface.SOLUTION: After a mesh-like mask 13 is arranged above a substrate 2 as a printed object separately from the substrate 2, a paste pressing-out head 15 is moved in an opposite direction of a blade 15a while pressing the mask 13 against the substrate 2 by the blades 15a, and the blade 15a is slid on the mask 13. During the sliding, paste Pst is pressed out from between two blades 15a of the paste pressing-out head 15 and the paste Pst is pressed out from an opening 13h formed in the mask 13 toward the substrate 2 so as to transcribe the paste Pst on the substrate 2. The interval D between the two blades 15a is set to be smaller than dimension H in a travelling direction of the paste pressing-out head 15 in a non-opening part 13K of the mask 13.

Description

  An object of the present invention is to provide a screen printing machine and a screen printing method for transferring a paste to a printing material using a mesh-like mask.

  Conventionally, a gap type screen printing machine is known as a screen printing machine for transferring a paste to a substrate or other printed material. In this gap type screen printing machine, a photosensitive emulsion is applied to a mesh-like member made of metal fibers, and a mask (mesh-like mask) in which an opening is formed by printing a pattern on the photosensitive emulsion is formed above the printed material. After placing the paste on the mask and moving it while pressing the mask against the substrate with a squeegee, the paste is extruded from the opening of the mask into a pattern A paste having a corresponding shape is transferred onto the substrate. In the gap type screen printing machine, the squeegee pushes down the mask and advances on the substrate, and the mask is separated from the mask by the elastic restoring force of the mask itself immediately after the paste contacts the substrate and the paste is pushed out from the opening. The plate is released (see, for example, Patent Document 1).

  In the above-described plate separation, the area where the non-opening portion of the mask (the portion where the photosensitive emulsion is not removed) is in contact with the printing material moves according to the movement of the squeegee, but the non-opening that exists in an island shape within the opening of the mask. As for the portion, if the entire area of the non-opening portion is in contact with the printing material at the same time, bleeding and sagging are likely to occur in subsequent plate separation. In this respect, the edge of the lower edge of the squeegee is straight and sharp, and the mask is pressed against the substrate by line contact with a very narrow interval, so that the transfer of the non-opening portion of the mask can be performed satisfactorily.

Japanese Patent Laid-Open No. 2001-221935

  However, there is a limit to the amount of paste that can be pushed out of the mask opening by the squeegee, and there is a dent in the substrate, and the dent is sufficiently filled with the paste to form a flat printing surface on the substrate. However, when it is necessary to transfer the shape of the non-opening portion that exists in an island shape in the opening of the mask to a part of the flat printing surface, the non-opening portion can be transferred well, but the depression The part had a problem that the amount of paste filling was insufficient and it was difficult to form a flat printed surface.

  Therefore, the present invention provides a screen printing machine and a screen printing method capable of forming a flat printing surface on a substrate having a depression and transferring the shape of the non-opening portion to a part of the flat printing surface. The purpose is to provide.

  The screen printing machine according to claim 1, wherein the paste is pressed out from between a mesh-like mask placed above the printing material and spaced apart from the printing material, and between two blades provided facing each other. A paste press-out head that moves the paste press-out head in a direction opposite to the blade while pressing the mask against the substrate by the blade, and a slider that moves the blade on the mask; With the blade sliding on the mask, the paste is pressed out from between the two blades of the paste pressing head, and the paste is pushed out from the opening formed in the mask onto the substrate. A paste pressing means, and the distance between the two blades is smaller than the dimension of the non-opening portion of the mask in the traveling direction of the paste pressing head. There.

  The screen printing method according to claim 2, wherein a paste is applied from between an installation step of installing a mesh-like mask above the substrate to be separated from the substrate, and between two blades provided facing each other. The paste pressing head is moved in the direction opposite to the blade while the mask is pressed against the substrate by the two blades of the paste pressing head to be pressed, and the blade is slid on the mask. During sliding, the paste is squeezed out from between the two blades of the paste squeezing head, and the paste is transferred to the substrate by pushing out the paste from the opening formed in the mask. A screen printing method including a transfer step, wherein the distance between the two blades is such that the paste pressing head of the non-opening portion of the mask The direction of travel of less than the dimension.

  In the present invention, since the paste is supplied onto the substrate by the paste pressing head, even if the substrate has a depression, the depression can be sufficiently filled with the paste, and a flat printing surface can be formed on the substrate. . In this case, the dimension in the advancing direction of the paste press-out head in the region where the non-opening portion of the mask is in contact with the substrate is a size corresponding to the distance between the two blades, but the size is the paste of the non-opening portion of the mask. Since it is smaller than the dimension in the advancing direction of the extruding head, even if the non-opening portion exists in an island shape in the opening of the mask, the entire area of the non-opening portion does not contact the printing material at the same time, The shape of the non-opening portion can be clearly transferred to a part of the flat printing surface.

The side view of the screen printer in one embodiment of the present invention The top view of the mask with which the screen printing machine in one embodiment of this invention is equipped The partial expanded side view of the screen printer in one embodiment of this invention The block diagram which shows the control system of the screen printer in one embodiment of this invention The side view of the screen printer in one embodiment of the present invention (A) (b) (c) The partial side view of the screen printer in one embodiment of this invention (A) (b) The partial expanded sectional view of the board | substrate with which the paste was printed by the screen printer in one embodiment of this invention (A) (b) (c) The partial side view of the screen printer in one embodiment of this invention The partial side view of the screen printer in one embodiment of this invention

  Embodiments of the present invention will be described below with reference to the drawings. A screen printing machine 1 shown in FIG. 1 is a device that prints a paste Pst such as solder on the upper surface (printing surface 2 a) of a substrate 2 that is a printing object, and a moving table 11 that is movably provided with respect to a base 10. The holding table 12 is provided so as to be movable up and down. The holding table 12 is raised and lowered by driving the moving table 11, and the substrate 2 is held on the upper surface of the holding table 12. For convenience of explanation, the direction perpendicular to the paper surface of FIG. 1 is the X-axis direction, and the left-right direction of FIG. 1 is the Y-axis direction. Further, the vertical direction of the paper surface of FIG.

  Above the holding table 12, a mesh-like mask 13 having four sides supported by a rectangular mask frame 13W is installed in a horizontal posture. The mask 13 has a flat plate shape extending in the XY plane as shown in FIG. 2, and an opening 13h for defining the shape of the pattern for transferring the paste Pst to the printing surface 2a of the substrate 2 at the center. Is formed. The mask 13 is made of a mesh-like member made of metal fibers. After the photosensitive emulsion is applied to the mesh-like member, a photomask (pattern original) on which the pattern to be printed is drawn is brought into close contact with the photosensitive emulsion surface and exposed to printing. The opening 13h is formed by removing the portion of the photosensitive emulsion corresponding to the pattern. In the embodiment, the opening 13h has a rectangular shape for transferring the paste Pst to the printing surface 2a of the substrate 2 by solid coating, and a non-opening portion 13K ( The portion formed without removing the light-sensitive emulsion is present in the form of islands.

  In FIG. 1, a paste pressing head 15 is provided above a mask 13 so as to be movable by a head moving means 16. The head moving means 16 drives the first ball screw 16a extending in the Y-axis direction above the mask 13 by the first motor 16b, thereby moving the paste press-out head 15 in the horizontal direction and extending in the Z-axis direction. By driving the two-ball screw 16c by the second motor 16d, the paste pressing head 15 is moved in the vertical direction.

  In FIG. 1, the paste pressure head 15 accommodates the paste Pst therein, and has two blades 15a disposed at the lower end thereof so as to face each other in the Y-axis direction (that is, the movement direction of the paste pressure head 15). doing. The two blades 15a are inclined downward toward the lower portion of the center portion of the paste pressing head 15, and the tip portions thereof are close to each other and have a predetermined distance D in the horizontal direction (Y-axis direction). (FIG. 3). The distance D is a dimension H (FIG. 2 where the non-opening portion 13K is the non-opening portion 13K) of the non-opening portion 13K of the mask 13 in the direction of travel of the paste press-off head 15 (here, the Y-axis direction; When there are a plurality of dimensions, the dimension in the traveling direction of the smallest non-opening portion 13K is set smaller than the dimension in the traveling direction).

  The paste pressure head 15 is provided with paste pressure means 15b such as a cylinder. The paste pressure head 15 pressures the paste Pst from between the two blades 15a by the operation of the paste pressure means 15b. .

  The moving table 11 raises the holding table 12 holding the substrate 2, and brings the upper surface of the substrate 2 into contact with the lower surface of the mask 13.

  In FIG. 4, the lifting and lowering of the holding table 12 is performed by the control device 20 included in the screen printing machine 1 controlling the operation of the moving table 11, and the movement of the paste pressing head 15 in the horizontal direction and the vertical direction is controlled by the control device 20. Is performed by controlling the operation of the head moving means 16. Also, the operation of pressing the paste Pst by the paste pressing head 15 is performed by the control device 20 controlling the operation of the paste pressing means 15b.

  Next, a procedure (screen printing method) for printing the paste Pst on the substrate 2 by the screen printer 1 will be described. First, the control device 20 carries in the substrate 2 supplied from the outside by carrying-in means (not shown) and holds it on the upper surface of the holding table 12 (holding step). Then, the movable table 11 is operated to raise the holding table 12 until the upper surface of the substrate 2 is separated from the lower surface of the mask 13 by an arbitrary distance Sd (arrow A shown in FIG. 5). A mesh-like mask 13 is placed in a state of being separated from the substrate 2 above (FIG. 5: installation step).

  When the control device 20 installs the mask 13 above the substrate 2, the control device 20 controls the operation of the head moving means 16, and the blade 15 a of the paste press-out head 15 is moved to a region outside the Y axis direction of the opening 13 h of the mask 13. It is located above one end side. Then, the paste press-out head 15 is lowered, and the mask 13 is pressed down by the blade 15a of the paste press-out head 15 to press it against the printing surface 2a of the substrate 2 (FIG. 6A, arrow B shown in the figure). .

  When the controller 13 pushes down the mask 13 with the blade 15a of the paste press-out head 15 and presses it against the printing surface 2a of the substrate 2, the paste press-out head 15 is opposed to the blade 15a while maintaining the pressed state. The blade 15a is slid on the mask 13 by moving in the direction parallel to the mask 13 (Y-axis direction), and the paste Pst is applied from between the two blades 15a of the paste pressing head 15 during the sliding. The paste Pst is transferred to the substrate 2 by extruding the paste Pst from the opening 13h formed in the mask 13 to the substrate 2 which is the printing object (transfer process). Specifically, when the control device 20 pushes down the mask 13 with the blade 15a of the paste press-out head 15 and presses it against the printing surface 2a of the substrate 2, the paste press-out head 15 is moved in a direction parallel to the mask 13 (Y While moving in the axial direction (arrow C shown in FIG. 6B), the paste pressing means 15b is controlled so that the paste Pst is pressed between the two blades 15a of the paste pressing head 15. When the blade 15a reaches the other end side of the region outside the opening 13h in the Y-axis direction, the movement of the paste press-out head 15 is stopped (FIG. 6C), and from the paste press-out head 15 Stop pressing the paste Pst.

  As described above, the screen printer 1 according to the present embodiment slides the blade 15a on the mask 13 by moving the paste pressing head 15 in the direction opposite to the blade 15a while pressing the mask 13 against the substrate 2 by the blade 15a. While the head moving means 16 and the blade 15 a are sliding on the mask 13, the opening 13 h formed in the mask 13 by pressing the paste Pst from between the two blades 15 a of the paste pressing head 15. The paste pressing means 15b for extruding the paste Pst onto the substrate 2 is provided.

  By the transfer step, the paste Pst discharged from the paste pressing head 15 passes through the mesh member in the opening 13 h of the mask 13 and is supplied to the printing surface 2 a of the substrate 2. For this reason, as shown in the enlarged view of FIG. 2, when the printing surface 2a of the substrate 2 has a depression 2b, a sufficient amount of paste Pst is also supplied into the depression 2b, and the depression 2b is sufficiently filled (FIG. 7A), and a flat printing surface 2c is formed on the substrate 2 (FIG. 7B).

  Further, when the blade 15a passes through the non-opening portion 13K existing in an island shape in the opening 13h of the mask 13, first, the leading side in the traveling direction of the paste press-out head 15 (arrow C shown in FIG. 8). The blade 15a (the right side in FIG. 8) rides on the non-opening portion 13K from one end side (the left side in FIG. 8) (FIG. 8A). Then, the blade 15a on the trailing side (left side of the paper in FIG. 8) of the traveling direction before the blade 15a on the leading side in the traveling direction descends from the other end side (the right side of the paper in FIG. 8) of the non-opening portion 13K. It rides on the opening portion 13K, and the non-opening portion 13K starts separating from the one end side (FIG. 8B). Such a situation is caused by the fact that the distance D between the two blades 15a of the paste pressing head 15 facing in the traveling direction is smaller than the dimension H in the traveling direction of the non-opening portion 13K.

  As described above, when the trailing blade 15a in the traveling direction rides on the non-opening portion 13K, the leading blade 15a in the traveling direction descends from the other end side of the non-opening portion 13K (FIG. 8C), Thereafter, when the trailing blade 15a in the traveling direction descends from the other end side of the non-opening portion 13K, the entire area of the non-opening portion 13K is separated from the substrate 2 (FIG. 9), and the plate separation of the non-opening portion 13K is completed. The transfer portion 2K of the non-opening portion 13K is formed on the substrate 2.

  Thus, when the transfer portion 2K of the non-opening portion 13K is formed on the substrate 2, the dimension in the traveling direction of the region where the non-opening portion 13K of the mask 13 is in contact with the substrate 2 is the distance between the two blades 15a. Although the dimension corresponds to D, the dimension is smaller than the dimension H in the advancing direction of the non-opening portion 13K of the mask 13, and therefore the non-opening portion 13K exists in an island shape in the opening 13h of the mask 13. Even if it exists, the whole area of the non-opening portion 13K is not brought into contact with the substrate 2 at the same time, and the non-opening portion 13K can be clearly transferred (printed) without causing bleeding or sagging.

  When the paste pressing head 15 is moved in the Y-axis direction and printing of the paste Pst on the substrate 2 is executed as described above, the control device 20 lowers the holding table 12, and the substrate 2 is screened by unillustrated unloading means. Unload from the printer 1. Thereby, the screen printing per sheet of the substrate 2 is completed.

  As described above, in the screen printer 1 and the screen printing method according to the present embodiment, the paste Pst is supplied onto the substrate 2 by the paste pressing head 15, so that even if the substrate 2 has the recess 2 b, the recess The portion 2b can be sufficiently filled with the paste Pst, and a flat printing surface 2c can be formed on the substrate 2. In this case, the dimension in the advancing direction of the paste pressing head 15 in the region where the non-opening portion 13K of the mask 13 is in contact with the substrate 2 is a dimension corresponding to the distance D between the two blades 15a. Since the non-opening portion 13K is smaller than the dimension H in the traveling direction of the paste pressing head 15, the non-opening portion 13K is formed even when the non-opening portion 13K exists in the opening 13h of the mask 13 in an island shape. The shape of the non-opening portion 13K can be transferred cleanly to a part of the flat printing surface 2c without simultaneously contacting the entire area of the substrate 2 with the substrate 2.

  Provided are a screen printing machine and a screen printing method capable of forming a flat printing surface on a substrate having a depression and transferring the shape of a non-opening portion to a part of the flat printing surface.

1 Screen printer 2 Substrate (substrate)
13 Mask 15 Paste Pressing Head 15a Blade 15b Paste Pressing Unit 16 Head Moving Unit D Interval H Size Pst Paste

Claims (2)

A mesh-like mask installed above the substrate to be separated from the substrate;
A paste extruding head for extruding the paste from between two blades provided facing each other;
A head moving means for sliding the blade on the mask by moving the paste pressing head in a direction opposite to the blade while pressing the mask against the substrate by the blade;
While the blade is sliding on the mask, the paste is pressed out from between the two blades of the paste pressing head, and the paste is pushed out from the opening formed in the mask onto the substrate. Paste extruding means
The screen printing machine, wherein a distance between the two blades is smaller than a dimension of the non-opening portion of the mask in the traveling direction of the paste pressing head. An installation step of installing a mesh-like mask in a state of being separated from the printing material above the printing material;
While pressing the mask against the substrate by the two blades of the paste pressing head for pressing the paste from between the two blades provided opposite to each other, the paste pressing head is moved in the opposite direction of the blade. The blade is slid on the mask while being moved, and during the sliding, the paste is squeezed out from between the two blades of the paste squeezing head to open the cover from the opening formed in the mask. A screen printing method comprising a transfer step of transferring the paste to the substrate by extruding the paste on the printed material,
2. The screen printing method according to claim 1, wherein a distance between the two blades is smaller than a dimension of the non-opening portion of the mask in the traveling direction of the paste pressing head.

Images