JPH0684068B2 - Screen frame and screen printing machine using the screen frame - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is provided with a gauze frame used in screen printing used for manufacturing printed wiring, thick film ICs, hybrid circuits, and the like, and a gauze frame. Screen printing machine.

[Conventional technology]

Screen printing is a gauze (screen) stretched over a gauze frame.
Then, a screen printing plate was produced by forming a figure and a pattern consisting of an opening and a non-opening mainly by a photoengraving method, printing ink was placed on the screen printing plate, and a squeegee was slid on the gauze surface. By pushing out the ink from the opening, the figure on the surface to be printed placed under the gauze,
This is a printing method that transfers a pattern.

This screen printing is widely used in various industrial fields because it can transfer ink thickly to the surface to be printed, can print on hard objects and curved surfaces, and has a wide range of ink selection. It is also used in the industry to form printed wiring and hybrid circuits. And
Particularly in the electronic industry, there is a demand for improvement in printing quality as the circuit becomes higher in density. The factors that determine the quality of print quality are the figure and pattern cumulative dimensional accuracy (the degree of misalignment at each coordinate position between the printing plate and the printed material, which is caused by the sliding resistance when the squeegee slides on the mesh). The line width accuracy (fineness) of the print pattern, the thickness accuracy of the print pattern, and the resolution are considered, and some or all of them are required to be highly accurate and fine in the electronic industry. In the past, it has been attempted to meet the above demands by selecting and improving the material and structure of the gauze, optimizing the gap between the gauze and the printing object, optimizing the printing conditions, and the like.

FIG. 3 shows the configuration of a conventional gauze frame. The conventional gauze frame has a structure in which a gauze 2 is attached to a rectangular frame body 1 made of wood or metal by bonding the gauze 2 while pulling its four sides so as to have a prescribed tension (tension). . When printing is performed, as shown in the schematic side view of FIG. 4, the space between the printing object 4 and the gauze 2 placed and fixed on the printing object table (stage) 3 by vacuum suction or another method. A gap (gap) d is taken in, the frame 1 is fixed, and the gauze frame is set in the printer main body. At this time, the gauze 2 is in a state of being stretched horizontally as shown by a chain double-dashed line. In this state, the ink 5 is applied onto the gauze 2, and then the squeegee 6 is brought into pressure contact with the gauze 2 to press the gauze 2 against the surface of the material 4 to be printed. At this time, the gauze 2 is stretched to the state shown by the solid line. In this state, the squeegee 6 is moved in the direction shown by the arrow, and the ink 5 is transferred to the printing object 4 through the opening of the gauze 2. Then, as the squeegee 6 moves, the gauze 2 is gradually separated by the tension thereof, so-called plate separation, and the printed material 4 is removed.
The contact position of moves, and printing is performed.

By the way, the gauze 2 is formed of either a woven fabric using fibers such as nylon or polyester, or etching metal such as stainless steel, or made by a plating method. In general, the gauze made of chemical fiber has elasticity, so that the gap d can be increased, and since the elasticity is large and the gap is large, plate separation is good. Therefore, the dimensional accuracy of the line width of the printing pattern is good. Is good. On the other hand, the metallic gauze has a small amount of elongation with respect to the pressing force of the squeegee, and therefore the gap d cannot be small (about 0.5 to 1 mm), but the elongation is small and the gap is small. Has a characteristic that the cumulative dimensional accuracy of is good.

Further, as shown in FIG. 5, the metal mesh 7 and the elastic coating 8 such as polyester mesh are partially overlapped with each other at the peripheral edge of the metal mesh 7, and the both are joined by an adhesive or the like at the overlapping portion 9. There is a combination type gauze frame configured by forming one gauze as a single piece and attaching the gauze to a rectangular frame body 1 ′ while pulling the elastic coating 8 to give tension. This combination type gauze frame has both the characteristics of the chemical fiber gauze and the characteristics of the metal gauze described above.

[Problems to be Solved by the Invention]

However, since the gauze frame using the gauze made of chemical fiber has a large gap in order to improve the plate separation,
The amount of elongation of the gauze during printing becomes large, and the restoring force of the gauze decreases and the creep (gradual extension) phenomenon is observed during repeated printing. When the gauze is permanently stretched in this way, the plate separation is not constant, the dimensional accuracy of the line width of the print pattern changes, and the quality of the printed matter changes.

In addition, a gauze frame using a metal gauze has the advantage that the cumulative dimensional accuracy of figures and patterns is good as described above, but the elasticity of the gauze is extremely small and the gap must be small. Since the plate separation is poor, the quality of the printed matter cannot be said to be good in terms of the line width accuracy of the print pattern among the quality determination factors.

Furthermore, the combination type gauze was developed to have the advantages of the chemical fiber gauze and the metal gauze, but since the polyester mesh is used for the elastic coating, printing is not possible. As it is repeated, permanent elongation still occurs in that portion, and the same problem as in the case of the above-mentioned chemical fiber gauze remains. Moreover, in this type of gauze, since the overlapping portion 9 has a laminated structure including an elastic coating, a metal mesh and the both, for example, an adhesive layer, the rigidity of the overlapping portion 9 is different from that of the other metal mesh 7. Since it is higher than that of the elastic coating 8 and the portion of the elastic coating 8, unnecessary deformation occurs at the boundary portion between the overlapping portion 9 and the metal mesh 7 and the elastic coating 8, and as a result, the dimensional accuracy of the line width of the print pattern is adversely affected. There is also the possibility that a new problem such as an impact will occur.

This invention has been made in view of the above circumstances,
When using a gauze made of chemical fiber, the permanent elongation of the gauze can be minimized to keep the plate separation as constant as possible, and when a metal gauze is used,
(EN) Provided is a gauze frame in which the gap can be set to an appropriate value in order to improve plate separation, and which does not have the above-mentioned problems in a gombination type gauze frame, and a screen printing machine using the gauze frame. This is a technical issue.

[Means for Solving the Problems]

As a means for achieving the above-mentioned object, the present invention does not use a rectangular frame body such as a conventional gauze frame, but disposes a pair of mounting frame bodies so as to be spaced apart from each other and arranged in parallel with each other. A gauze is stretched between the frame bodies, and both mounting frame bodies are vertically engaged or engaged with one end portions of the mounting frame bodies by guide means such as a pair of guide rods. The attachment frame body is attached to the guide rods so that the other end portions of the attachment frame body are vertically and slidably engaged with the respective guide rods so as to be connected to each other and further slidably engaged with the guide means. The gist is that the gauze frame is constructed by attaching elastic means to the.

The gauze is made of chemical fiber or metal mesh.
Also, the spring constant of the elastic means may be set smaller than the spring constant of the gauze.

Then, while fixing one of the attachment frame bodies of the gauze frame having the above-mentioned structure to a frame body holding portion formed in the machine body, each tip end of guide means such as a pair of guide rods in the gauze frame is formed in the machine body. The elastic means is fixed to the guide means holding portion, and the elastic means is attached to the mounting frame body slidably engaged with the guide means.
The screen printing machine according to the present invention is configured by attaching the attachment frame body so as to urge the gauze of the gauze frame in the direction of applying tension.

[Action]

When setting the gauze frame with the above-mentioned configuration in the printing machine body as described above and printing with the screen printing machine,
When a gauze made of chemical fibers is used, the gauze stretches when the squeegee is pressed against the gauze and the gauze is brought into contact with the material to be printed, but due to the increase in tension generated in the gauze, it is slidably engaged with the guide rod. The mounting frame body is slightly moved to the other mounting frame body against the elastic force of the elastic means, and the tension of the gauze and the elastic force of the elastic means oppose each other. And gauze are retained. In this way, as compared with the conventional gauze frame in which the frame body is fixed, the amount of expansion of the gauze during printing is reduced by the movement distance of the mounting frame body, so that the permanent elongation of the gauze is minimized. Therefore, the plate separation can be kept as constant as possible. The above effect is enhanced as the spring constant of the elastic means is set smaller than that of the chemical fiber gauze.

Also, when the gauze is formed of a metal mesh, the gauze has extremely low elasticity and the amount of elongation of the gauze itself is very small, but when the squeegee is pressed against the gauze during printing, the gauze will be deformed at that time. , The mounting frame slidably engaged with the guide bar is pulled through the gauze against the elastic force of the elastic means, and the mounting frame is separated by the distance excluding the extension of the gauze. It can be moved towards the mounting frame. In this way, since one of the frames can be moved, the gap can be set large even if the amount of elongation of the gauze itself during printing is extremely small. Because it is given, the plate separation is improved. Also in this case, the plate separation becomes better as the spring constant of the elastic means is set smaller than that of the gauze.

Then, when printing is completed and the pressing force of the squeegee applied to the gauze is released, the mounting frame body slidably engaged with the guide rod returns to its original position by the restoring force of the elastic means.

Further, since both mounting frame bodies are respectively engaged with and held by the pair of guide bars, the work of stretching the mounting frame body can be performed relatively easily.

〔Example〕

A preferred embodiment of the present invention will be described below with reference to FIGS.
Description will be given with reference to the drawings.

FIG. 1 is a plan view showing a main part of a printing machine main body to which a gauze frame according to an embodiment of the present invention is attached, and FIG. 2 is a front view thereof. The gauze frame 10 includes a fixed side mounting frame body 12 and a movable side mounting frame body 14, which are arranged in parallel with each other with a gap, a gauze 16 stretched between the pair of mounting frame bodies 12 and 14, and a pair. The guide rods 18, 18 and the tension coil spring 20 attached to the movable side mounting frame body 14 are included. Pair of guide bars
18 and 18 are arranged in parallel, one end of each of which is fitted and fixed to both ends of the fixed-side mounting frame 12. In addition, each one end of the guide rods 18, 18 and the fixed side mounting frame body
Since the other ends of the guide rods 18 and 18 are fixed to the guide rod holding portion 28 as described later, the guide rod 12 may be loosely fitted without being fixed. Further, the movable side mounting frame body 14 has the other ends of the guide rods 18 and 18 inserted therethrough, and the movable side mounting frame body 14 is fixed to the fixed side mounting frame body 12 at both ends thereof via the bearing 22. The guide rods 18, 18 are slidably engaged in parallel with each other. In addition, the movable side mounting frame body 14 has guide rods 18, 18
If it can slide smoothly and move smoothly, the movable side mounting frame
It is not necessary to provide a bearing on 14 in particular. The gauze 16 is made of chemical fiber such as nylon or polyester, or metal mesh such as stainless steel.

In order to attach the gauze frame 10 having the above structure to the main body of the printing machine, first, the fixed side attachment frame body 12 is formed into the frame body holding section 24 formed on the machine body.
It is fixed with a fixing screw 26. Next, while the guide rods 18, 18 are inserted into the movable side mounting frame body 14, one end portion is attached to the fixed side mounting frame portion 12, and the other end portion is held by the guide rod formed on the machine body. It is fixed to the portion 28 by a mounting screw 30. Then, one end of the tension coil spring 20 is fixed to the movable side mounting frame body 14, and the other end is fixed to the fixed portion 32 of the machine body. The tension coil spring 20 pulls the movable-side mounting frame body 14 in a direction away from the fixed-side mounting frame body 12 to apply tension to the gauze 16. Here, the spring force of the tension coil spring 20 is set so that the gauze tension required for screen printing is given. When the spring constant of the gauze 16 is Ks and the spring constant of the tension coil spring 20 is K, The spring constant of the tension coil spring 20 is set so that the condition of Ks ≧ K is satisfied. Of course, even if Ks <K, this invention does not mean that it does not hold true. The states shown by the solid lines in FIGS. 1 and 2 are the positions of the movable side mounting frame body 14 and the gauze 16 before printing.

Next, the state of the movable side mounting frame body 14 and the gauze 16 in the case where the printing object 36 is placed and fixed on the stage 34 by means such as vacuum suction and screen printing is performed will be described. Now, when a squeegee (not shown) is pressed against the upper surface of the gauze 16, the gauze 16 contacts the material 36 to be printed and bends as shown by the chain double-dashed line in FIG. Here, when the gauze 16 is formed of chemical fibers, the gauze 16 expands, but the tension of the gauze 16 increases accordingly. Due to the increase in the tension, the movable-side mounting frame body 14 slightly moves in the arrow direction along the guide rods 18 and 18 against the force of the tension coil spring 20 and reaches the position shown by the chain double-dashed line. . Since the movable side mounting frame body 14 moves in the direction of the arrow in this way, the expansion amount of the gauze 16 decreases by the movement distance. When the spring constant between the gauze 16 and the tension coil spring 20 is set to Ks> K, and the difference between them is increased,
The moving distance of the movable side mounting frame body 14 becomes larger, and the amount of expansion of the gauze 16 also becomes smaller accordingly.

When the gauze 16 is made of a metal mesh,
Since the elasticity of the gauze is extremely small and the amount of expansion of the gauze itself is extremely small, when the gauze 16 is bent as shown by the chain double-dashed line in FIG. 2, the movable side mounting frame body 14 is forced by the force of the tension coil spring 20. It is pulled by gauze 16 and moves in the direction of the arrow.
In this way, since the movable side mounting frame body 14 is movable,
Even if the gauze 16 itself has an extremely small amount of expansion, it is possible to set a large gap.
Since it is tensioned by, the plate separation is good.

When printing is finished and the pressing force of the squeegee on the gauze 16 is released, the movable side mounting frame body 14 moves along the guide rods 18, 18 in the direction opposite to the arrow by the restoring force of the tension coil spring 20, and Return to the position.

The configuration of the present invention is as described above, but the scope of the present invention is not limited by the above description and the contents of the drawings, and various modifications can be included without departing from the scope of the invention. For example, in the above-described embodiment, the mounting frame and the guide rod that is the guide means are provided with through holes in the mounting frame,
Although the guide rod is engaged by inserting it through the through hole, the guide rod is a square rod, and a groove is formed on the lower surface of the mounting frame body so that the groove and the square rod are engaged with each other. May be. Further, the guide means may be a rod-shaped body having a guide groove formed in its longitudinal direction, and in this case, both ends of the movable side mounting frame may be configured to slidably engage with the guide groove. . Further, the fixing means of each mounting frame body to the printer main body is not limited to screwing, and various methods can be adopted. Further, a compression coil spring is used in place of the tension coil spring, and the compression coil spring is wound between the two mounting frames of the guide rod or is interposed between the fixed part of the printing press main body and the movable side mounting frame. You may also wear it.

〔The invention's effect〕

Since the present invention is configured and operates as described above, when the gauze frame according to the present invention is set in a screen printing machine for printing, when a gauze made of chemical fiber is used, the gauze of the gauze frame is used. Since the permanent elongation of the printing pattern can be minimized and the plate separation can be kept as constant as possible, the dimensional accuracy of the line width of the printing pattern can be kept constant for a long period of time, and the quality of the printed matter can be improved. Stabilize. And
When the spring constant of the elastic means is set smaller than the spring constant of the gauze, the life of the gauze is extended.

In addition, when a metal mesh gauze is used, the plate separation can be improved, so that the dimensional accuracy of the line width of the printed pattern can be improved as well as the cumulative dimensional accuracy of the figure and pattern, and the quality of the printed matter can be improved. It can be increased overall.

Moreover, in the gauze frame according to the present invention, there is no problem as in the gauze frame of the conventional combination system.

[Brief description of drawings]

FIG. 1 is a plan view showing a main part of a printing press main body to which a gauze frame according to an embodiment of the present invention is attached, FIG. 2 is a front view of the same, and FIG. 3 shows a structure of a conventional gauze frame. FIG. 4 is a schematic side view showing a state when screen printing is performed using a conventional mesh frame, and FIG. 5 is a plan view showing another configuration example of the conventional mesh frame. 10 …… gauze frame, 12 …… fixed side mounting frame body 14 …… movable side mounting frame body, 16 …… gauze, 18 …… guide rod, 20 …… tension coil spring, 24 …… frame body holding part, 28 …… Guide bar holding part, 32 …… Fixing part.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Makoto Sawada Makoto Sawada, Kyoto Prefecture, Kyoto City, Horikawa-dori Teranouchi 1-chome, Tenjin Kitamachi 1-chome, Dainippon Screen Mfg. Co., Ltd. (72) Inventor Hideki Adachi Kyoto 1 Nihon screen manufacturing Co., Ltd., 1-chome Tenjin Kitamachi 4-chome, Horikawa-dori Teranouchi, Kamigyo-ku, Kyoto, Japan (56) Reference JP-A-1-275139 (JP, A) JP-B-4014636 ( JP, B2)

Claims (3)

[Claims] 1. A pair of mounting frame bodies arranged in parallel with each other to stretch a gauze, and one end of each of the mounting frame bodies is engaged with or engaged with one of both end portions of the mounting frame body. A pair of guide means slidably engaged with the other ends of the mounting frame body, and a resilient member attached to the mounting frame body slidably engaged with the guide means. A gauze frame made up of means. 2. The gauze frame according to claim 1, wherein the spring constant of the elastic means is set smaller than the spring constant of the gauze. 3. One of the attachment frame bodies of the gauze frame according to claim 1 or 2 is fixed to a frame body holding portion formed on the machine body, and each tip portion of the pair of guide means of the gauze frame is fixed. The elastic means is fixed to the guide means holding portion formed on the machine body, and the elastic means is attached to the attaching frame body slidably engaged with the guide means in the direction of applying tension to the gauze of the gauze frame. A screen printing machine in which the frame is attached so as to urge it.