JP2003191434A - Screen process printer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a screen process printer capable of securing a sufficient ink transition amount and thereby, performing a rapid printing process. <P>SOLUTION: The screen process printer 10 comprises a rotary screen 26 with an internally arranged ink supply pipe 33, an impression cylinder 39 which is disposed opposite to the rotary screen 26 and feeds a printing paper P, a squeegee 35 which is disposed inside the rotary screen 26 and supplies ink I to screen meshes A and a doctor 37 juxtaposed with the squeegee 35. The doctor 37 preliminarily feeds the ink I to not only the screen meshes A but also the squeegee 35. <P>COPYRIGHT: (C)2003,JPO

Description

Description: BACKGROUND OF THE INVENTION [0001] 1. Field of the Invention [0002] The present invention relates to a screen printing apparatus, and more particularly, to a screen printing apparatus capable of performing printing with a large amount of ink to be transferred. . [0002] Conventionally, a screen printing apparatus has been known as an apparatus for printing braille or the like. The screen printing apparatus includes a rotary screen, an impression cylinder facing the rotary screen, and a squeegee disposed in the rotary screen. The squeegee is made to pass printing paper between the rotary screen and the impression cylinder. Thus, the ink extruded from the fine plate holes formed on the outer peripheral surface of the rotary screen is transferred. That is, as schematically shown in FIG.
The rotary screen 50 includes, for example, a stainless steel layer 50A having a thickness of about 150 μm in which a predetermined number of small holes 51 are formed for each plate hole A having a diameter of about 1.5 mm, and a stainless layer 50A excluding the plate hole A. Thickness of about 200 provided on the surface
and a photosensitive layer 50B made of a μm emulsion.
The ink I pushed out from the small hole 51 by the squeegee 53 inside the stainless steel layer 50A (upper side in FIG. 5) is transferred to the printing paper P. [0005] However, in the conventional screen printing apparatus, the maximum height H of the ink I transferred to the printing paper P is at most as shown in FIG. The height is about 100 μm to 150 μm, and there is a disadvantage that the height in Braille printing cannot be sufficiently secured. This is because the squeegee 53 cannot supply ink sufficiently during high-speed printing. Therefore, in order to supply ink sufficiently, the printing speed must be reduced, which is a factor that hinders high-speed printing. SUMMARY OF THE INVENTION The present invention has been made in view of such inconveniences, and has as its object to provide a screen capable of performing a high-speed printing while ensuring a sufficient amount of ink transfer. A printing device is provided. In order to achieve the above object, the present invention provides a rotary screen, an impression cylinder facing the rotary screen, and an ink supply pipe extending through the rotary screen. A screen printing apparatus, comprising: a squeegee for guiding ink to the inner peripheral surface side of the rotary screen; and printing on the printing paper by passing printing paper between the rotary screen and the impression cylinder. In addition, at least one doctor is juxtaposed and provided so that the ink can be preliminarily supplied to the plate hole by the doctor. With such a configuration, the ink is additionally supplied by the squeegee after the ink is supplied to the plate hole by the doctor, and the amount of the ink to be transferred can be increased. Therefore, as a result of an increase in the amount of ink extruded from the plate hole of the rotary screen,
High-speed printing can be performed while securing a large amount of transfer to printing paper. Therefore, for example, when applied to Braille printing, it is possible to make the protruding height of the Braille sufficient. [0006] In this specification, "printing paper" is used for a sheet containing paper. An embodiment of the present invention will be described below. FIG. 1 shows an overall configuration diagram in which a screen printing apparatus 10 is incorporated in a flexographic printing press 11. In this figure, the flexographic printing press 1
1, a plurality of printing units 12 are provided, and the screen printing apparatus 10 is arranged above the first printing unit 12 located on the left side. Each printing unit 12 has an ink pan 15
And a fountain roll 16 disposed in the ink pan 15, an anilox roll 17 to which ink is transferred via the fountain roll 16, a plate cylinder 18 facing the anilox roll 17, and a printing paper P.
And an impression cylinder 19 that faces each other. On the upstream side (the left side in FIG. 1) of the printing unit 12, an original fabric 20 obtained by winding a printing paper P on which a label substrate is stuck on a release liner in a roll shape is disposed. The printing paper P sent from the material web 20 (unwinder) passes through each printing unit 12 in a state of being wound around a number of rollers, so that desired printing is performed. On the downstream side (right side in FIG. 1) of the printing unit 12, a film F
, A die-cutting device 22A, 22B for hollowing out the laminated printing paper P into a predetermined planar shape, and an outer peripheral portion F of the printing paper P hollowed out by the die-cutting device 22A or 22B. Scrap winding devices 23A and 23B and winding devices 24A and 24B (winders) for winding the final product are arranged. Here, the die cutting devices 22A and 22B, the scrap winding devices 23A and 23B, and the winding devices 24A and 24B are selectively used, so that continuous processing can be performed without stopping the operation of the entire device. Is possible. The screen printing apparatus 10 is provided so as to be adjustable in position along a rail R provided above the printing unit 12. In the present embodiment, the screen printing apparatus 10 is arranged above the first printing unit 12. I have. As shown in FIGS. 2 and 3, the screen printing apparatus 10 has a cylindrical rotary screen 26 having both ends opened in the axial direction.
A pair of lid members 27, 27 (see FIG. 2) fitted to both ends of the rotary screen 26;
Four free rollers 29 that are arranged on the outer peripheral surfaces of the outer peripheral surfaces of the outer peripheral surfaces 7 and 27 at intervals of approximately 90 degrees in the circumferential direction and contact the lid members 27 and 27, and a fourth free roller 29 fixed to the outer peripheral surface of each lid member 27. A first gear 30 and a second gear 31 for transmitting a rotational driving force of a motor (not shown) to the first gear 30
An ink supply pipe 33 extending into the rotary screen 26 so as to penetrate between the lid members 27, 27; a squeegee 35 supported on the ink supply pipe 33 via a pair of brackets 34; Supply pipe 33
And a doctor 37 supported via a pair of brackets 36, 36. Each free roller 29 is supported by a predetermined support shaft, and the rotary screen 26 is rotatably supported via these free rollers 29. On the other hand, the ink supply pipe 33 has a shaft end fixedly supported via a support device (not shown). The rotary screen 26 is shown in FIG.
As schematically shown in (A), a stainless steel layer 26A in which a number of small holes 38 (mesh) are formed in a plate hole A formed for each predetermined region, and the plate hole A is formed in the stainless layer 26A. And a photosensitive layer 26B made of an emulsion provided on the surface except for the photosensitive layer 26B. Each of these layers 26
The layer thicknesses of A and 26B are substantially the same as in the conventional example, but such layer thicknesses do not limit the present invention in any way. As shown in FIG. 3, the squeegee 3
Reference numeral 5 denotes a plate-like member, which is provided with a resin material 35A at its tip. The squeegee 35 is provided such that the resin material 35A is located in a contact area between the rotary screen 26 and the impression cylinder 39. The doctor 37 also has a similar plate shape, and is provided with a resin material 37A at its tip. This doctor 37, with respect to the squeegee 35,
The ink I collected in the doctor 37 is arranged in a row immediately before the rotary screen 26 in the rotation direction V.
Is preliminarily supplied to the small hole 38 (mesh), and can also be supplied to the squeegee 35 through a hole 41 provided in the middle of the doctor 37. An ink supply hole 33A having a substantially elliptical opening is formed in the middle of the ink supply pipe 33, and the squeegee 3 is provided through the ink supply hole 33A.
5 and the doctor 37 are supplied with ink. Also,
The ink supply pipe 33 is provided with an ink supply port 42 at one end thereof, and the ink I is supplied into the ink supply pipe 33 from the ink supply port 42. Next, the overall operation of this embodiment will be described. The printing paper P to be printed is sent out from the unwinder of the raw material 20, passed through each printing unit 12, the screen printing device 10, and the die cutting device 22A, and the lead end thereof is fixed to the winder of the winding device 24A or 24B. Make initial settings. When a predetermined power is turned on, the printing paper P is sequentially fed out, and ink of a preset color is printed in each printing unit 12, while printing or printing of each set color is performed in the screen printing apparatus 10. Braille (dots) are printed. In the screen printing apparatus 10, the rotary screen 10 rotates, and the ink supply pipe 3 extending inside is rotated.
The ink I flows out from the ink supply hole 33A of the third nozzle 3, and the ink I flows along the surface of the doctor 37, and the resin material 37A at the tip end.
Are collected on the side close to the inner wall surface of the rotary screen 10. Further, the ink I flows along the opening 41 on the surface of the doctor 37 and is collected in the squeegee 35 area, and also flows out toward the resin material 35A at the tip of the squeegee 35. Therefore, the small hole 3 is located near the distal end of the doctor 37.
8 (mesh), the ink I can be preliminarily supplied (see FIG. 4 (A)).
The ink I extruded from the small holes 38 formed in the stainless steel layer 26A of the rotary screen 26 inscribed with the resin material 35A at the tip of No. 5 is extruded into the plate holes A (see FIG. 4B). Thereby, the transfer amount to the printing paper P passing between the rotary screen 26 and the impression cylinder 39 can be reduced by the conventional squeegee 53 only in FIG.
The amount of the ink I can be increased more rapidly than the method (B), and the transferred thickness, that is, the height H of Braille can be increased as compared with the conventional method. Therefore, after the ink is transferred to the printing paper P through the plate hole A, almost no ink I remains in the plate hole A from the start of the initial printing (FIG. 4).
(C)). On the printing surface of the printing paper P that has passed through the printing unit 12 located at the most downstream, if necessary, the film F
Are laminated, and then the die-cutting device 22A or 2A is moved along the contour corresponding to the preset label shape.
The printing paper P is die-cut by 2B. Then, the outer part E (waste) of the printing paper P is taken up by the take-up device 23A or 23B, while the final product is taken up by the take-up device 24A or 24B. In the above-described embodiment, the case where the number of the doctor 37 is one has been shown and described. However, the present invention is not limited to this, and can be further increased. In short, the present invention only needs to have a structure capable of eliminating insufficient transfer by supplying the ink I to the plate hole A in advance through the small holes 38 (mesh). As described above, according to the present invention,
Since a doctor can be side-by-side with the squeegee and ink can be preliminarily supplied to the plate holes by the doctor, the doctor can preliminarily supply ink to the plate holes of the rotary screen, and the ink pushed out by the squeegee is As a result, the amount of ink extruded from the plate hole can be increased. Therefore, it is possible to secure a large amount of transfer to printing paper. For example, when the present screen printing apparatus is applied to Braille printing, it is possible to realize high-speed printing while making the amount of ink protrusion sufficient. Becomes possible.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a front view showing the entire configuration of a flexographic printing press to which a screen printing device is applied. FIG. 2 is an enlarged side view of the screen printing apparatus. FIG. 3 is a cross-sectional view of the screen printing apparatus as viewed in the direction of arrows in FIGS. FIG. 4A is a schematic cross-sectional view showing a state where ink is preliminary discharged into a plate hole by a doctor, and FIG. 4B is a schematic cross-sectional view showing a state where ink is further discharged and supplied to a plate hole by a squeegee. (C) is a sectional view showing a state in which the ink is transferred to the printing paper. FIGS. 5A and 5B are cross-sectional views showing a transfer operation in a conventional screen printing apparatus. [Description of Signs] 10 Screen printing device 26 Rotary screen 33 Ink supply tube 35 Squeegee 37 Doctor 39 Impression cylinder A Plate hole I Ink P Printing paper

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Akira Ichikawa             23-23 Honcho, Itabashi-ku, Tokyo Lintec stock             In the company F term (reference) 2C035 AA11 RA25 RA29 RA35 RA37

Claims (1)

Claims 1. A rotary screen having a plate hole formed on an outer peripheral surface thereof, an impression cylinder facing the rotary screen, and an ink supplied through an ink supply pipe extending into the rotary screen. A screen printing apparatus comprising: a squeegee for guiding an inner peripheral surface side of a rotary screen, and printing on the printing paper by passing a printing paper between the rotary screen and the impression cylinder. A screen printing apparatus, wherein one doctor is juxtaposed and said ink can be preliminarily supplied to said plate hole by said doctor.