JP2003010763A - Method and apparatus for applying masking agent and masking method apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reliably prevent the sticking of a masking agent on a non-coating part even when a circuit is made dense and the distance between a coating part and the non-coating part of the masking agent becomes narrow. SOLUTION: The tip surface 1a of a coating apparatus 1 including a discharge port 2 for the masking agent is formed flat to face the surface of a plate like member 3 such as a printed circuit board and is arranged to be provided with a prescribed gap (d) where the capillary action is caused between the tip surface and the surface of the plate like member to cover the coating surface 3a of the plate like member and the coating surface of the plate like member is coated with the masking agent by injecting the masking agent from the discharge port to the space. A projecting part 1b can be disposed on the outer circumferential edge of the tip surface.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a masking agent coating method and a masking device which can prevent the masking agent from adhering to a non-soldered portion when a moisture-proof masking agent is coated on a printed circuit board or the like.

[0002]

2. Description of the Related Art In general, a printed circuit board or the like measures the insulation of the circuit board by coating (masking) a gap between conductors of a circuit. A conventional method of applying a masking agent to a printed circuit board or the like is, as shown in FIG. 5 (a) a spray type nozzle and (b) a dot type nozzle,
Since there was a sufficient distance between the coated part and the non-coated part, the masking agent was discharged and applied to the coated part such as a printed circuit board by a nozzle. However, when the circuit on the printed circuit board becomes dense and the distance between the masking agent application part and the non-application part becomes narrow, the droplets of the masking agent ejected and applied to the application part adhere to the non-application part, There was a problem that the strength was insufficient and stains were caused due to the influence of adhesion (in the subsequent process).

[0003]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and an object thereof is to provide a dense circuit,
Provided are a masking agent applying method and a device thereof, and a masking method and an apparatus thereof, which surely prevent the masking agent from adhering to the non-application part even if the distance between the masking agent application part and the non-application part is narrowed. That is.

The present invention provides, as means for solving the above-mentioned problems, a masking agent application method and its apparatus, a mask method and its apparatus described in each of the claims. The masking agent application method according to claim 1, wherein the tip end surface of the application device including the discharge port, which is formed flat so as to face the surface of the flat plate-shaped member, covers the application surface of the flat plate-shaped member. A predetermined gap that causes a capillary action is provided between the surface of the flat plate-like member and the masking agent is injected from the discharge port into this gap.
As a result, the injected liquid masking agent can be reliably applied to the application surface of the flat plate-shaped member covered by the application device by the capillary action, and the masking agent can be prevented from adhering to the non-application surface due to splashes or the like. .

According to a second aspect of the present invention, there is provided a masking agent coating method, wherein a projection is formed on the outer peripheral edge of the tip end surface of the coating device, and the projection surface and the tip end are formed by bringing the projection into contact with the surface of the flat plate member. The masking agent is injected into the gap between the surfaces, which allows the gap between the coating device and the coating surface to be easily set to a predetermined gap, and the amount of masking agent injected can be controlled. It is possible to prevent reliable application to the coated surface and to prevent the non-coated surface from protruding. The masking agent application device according to claim 3 and claim 4
The inventions of the methods 2 and 2 are replaced with the inventions of the apparatus which are the product inventions, respectively, and the operation and effect thereof are the same as those of the method invention.

In the mask method according to a fifth aspect of the present invention, the mask device covers the non-coated surface of the flat plate-shaped member, and the protruding portion formed on the outer peripheral edge of the surface of the mask device facing the flat plate-shaped member, The masking agent is injected into the application surface of the flat plate-shaped member in a state of being held below a gap that causes a capillary action between the flat plate-shaped member and the surface of the flat plate-shaped member. The droplets of the masking agent that have flown between the plate-shaped members will enter between the protruding part and the flat plate-shaped member by the capillary action, and the masking agent will be pooled to ensure that the masking agent adheres to the non-coated surface. It can be prevented.
A mask device according to a sixth aspect is obtained by rewriting the invention of the method of the fifth aspect into a device invention which is a product invention, and its operation and effect are almost the same as those of the invention of the method.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION A masking agent application method and apparatus, a mask method and apparatus thereof according to an embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of a masking applicator according to a first embodiment of the present invention. A coating device 1 for coating a liquid masking agent on the surface of a flat plate-shaped member 3 such as a printed circuit board is provided with a discharge port 2 for discharging the masking agent so as to penetrate the substantially central portion thereof. Tip surface 1 facing flat member 3 of coating apparatus 1
a is formed flat so as to cover the application surface 3a of the flat plate-shaped member 3, and when the masking agent is applied to the application surface 3a, the front end surface 1a of the application device 1 and the flat-plate-shaped member 3 are applied. The coating device 1 is arranged so as to form a gap d between the surface 3a and the masking agent which causes a capillary action. Reference numeral 3b is a surface of the flat plate-shaped member 3 on which the masking agent is not applied. Further, as the masking agent, for example, an epoxy-based or polyurethane-based resin is used,
It is supplied by a known supply mechanism.

The operation of the masking agent coating device of the present invention having the above structure will be described. First, the flat plate member 3 such as a printed circuit board is positioned and held at a predetermined position. Next, the application device 1 covers the masking agent application surface 3 a of the flat plate-shaped member 3. At this time, the gap d between the tip surface 1a of the coating device 1 and the surface of the flat plate-shaped member 3 is such that the liquid masking agent causes a capillary action, for example, a gap of about 0.1 to 0.5 mm. Held in. Next, the masking agent is discharged from the discharge port 2 of the coating device 1 into the gap d. The discharged masking agent is applied to the tip surface 1a of the coating device 1 and the flat plate-shaped member 3
The gap d formed between the coated surface 3a and the coated surface 3a is spread to every corner by the capillary action, and the coated surface 3a is coated with the coating thickness h by the masking agent. At this time, by controlling the injection amount of the masking agent, the masking agent is held in the gap d, so that the masking agent is prevented from reaching the non-coated surface 3b of the flat plate-shaped member 3 by its surface tension. it can. The coating thickness h is substantially equal to the gap d.

FIG. 2 is a partially enlarged view of the masking agent coating device according to the second embodiment of the present invention. In this embodiment,
A protrusion 1 b that projects toward the surface of the flat plate-shaped member 3 is formed on the outer peripheral edge of the tip end surface 1 a of the coating device 1 that faces the coating surface 3 a of the flat-plate member 3. The height of this protrusion 1b is
It is formed to have the same length as the above-mentioned gap d. Therefore, by disposing the protrusion 1b in contact with the surface of the flat plate-shaped member 3, a gap d can be stably obtained between the tip surface 1a of the coating device 1 and the surface of the flat plate-shaped member 3, and the masking agent The application range and thickness become stable. Further, the protrusion 1b more effectively prevents the masking agent from protruding from the coated surface 3a to the non-coated surface 3b.

FIG. 3 is a schematic configuration diagram of a mask device according to a third embodiment of the present invention. The mask device 4 is provided to cover the non-coated surface 3b of the flat plate-shaped member 3 such as a printed circuit board. Flat plate-shaped member 3 of mask device 4
The front end portion 4a facing the surface of the plate 4 is formed with a protruding portion 4b on the outer peripheral edge thereof so as to protrude toward the surface of the flat plate-shaped member 3. When the mask device 4 is positioned so as to cover the non-coated surface 3b of the flat plate-shaped member 3, the gap d'between the end face of the protrusion 4b and the surface of the flat plate-shaped member 3 causes the masking agent to cause a capillary action. Below the gap, eg about 0.5
The mask device 4 is configured to be arranged on the surface of the flat plate-shaped member 3 so as to be equal to or less than mm. Naturally, the thickness (width) of the protruding portion 4b has a thickness required to cause a capillary action. In this case, the masking agent supplied to the coating surface 3a of the flat plate-shaped member 3 by a coating device (not shown) is not applied to the non-coating surface 3b due to the gap formed between the protruding portion 4b of the mask device 4 and the surface of the flat plate-shaped member 3. Prevented from going to. That is, the masking agent accumulates in the gap due to the capillary action, and the surface tension of the masking agent causes the non-application surface 3b to pass through the gap.
Prevented from going to. The protruding portion 4 of the mask device 4
You may arrange so that b may contact the surface of the flat plate-shaped member 3.

The operation of the mask device having the above structure will be described. First, the flat plate member 3 such as a printed circuit board is positioned and held at a predetermined position. Next, the mask device 4 covers the non-coated surface 3 b of the flat plate-shaped member 3. At this time, the mask device 4 is held on the flat plate-shaped member 3 so that the gap d ′ formed between the protruding portion 4b of the mask device 4 and the surface of the flat-plate-shaped member 3 is about 0.5 mm or less. . Next, a masking agent is supplied onto the coating surface 3a of the flat plate-shaped member 3 by a coating device (not shown) to coat the coating surface 3a. The masking agent that has been splashed as a droplet when the masking agent is applied is not applied to the non-applied surface 3 by the mask device 4 and its protrusion 4b.
Adhesion to b is prevented. In particular, the masking agent that jumps between the protrusion 4b and the surface of the flat plate-shaped member 3 is
The gap d'formed between the protrusion 4b and the surface of the flat plate-like member 3 enters by a capillary action and is held there by surface tension to be in a liquid storage state.
It can be surely prevented from adhering to.

FIG. 5 is a perspective view of a printed circuit board 3 which is a preferred example of the flat plate-shaped member 3 to which masking is applied. 3a indicates a coated surface and 3b indicates a non-coated surface.

As described above, in the masking agent application method and apparatus of the present invention, a predetermined gap that causes a capillary action is provided between the surface of the flat plate-like member and the application surface is covered by the application device. Then, by injecting a liquid masking agent into the gap between the coating surface and the coating device, and providing a protrusion on the coating device and bringing the protrusion into contact with the surface of the planar member, in a planar member such as a printed circuit board. Even if the circuit becomes dense and the distance between the masking agent application surface and the non-application surface becomes narrow, it is possible to reliably prevent the masking agent from adhering to the non-application portion. Similarly, in the mask method and the apparatus thereof according to the present invention, a protrusion having a predetermined thickness (width) is provided on the outer peripheral edge of the tip end surface of the mask device, and the gap between the protrusion and the surface of the flat plate-shaped member is maintained within a predetermined dimension. By doing so, in a flat plate-like member such as a printed circuit board, even if the circuit becomes dense and the distance between the masking agent application surface and the non-application surface becomes narrow, the masking agent will not be removed when the masking agent is applied. It can be surely prevented from adhering to the coated surface.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of a masking agent application device according to a first embodiment of the present invention.

FIG. 2 is a partially enlarged view of a masking agent application device according to a second embodiment of the present invention.

FIG. 3 is a schematic configuration diagram of a mask device according to a third embodiment of the present invention.

FIG. 4 is a diagram for explaining the operation of the mask device of the present invention.

FIG. 5 is a perspective view of a printed circuit board that is a preferred example of a flat plate member on which masking is applied.

FIG. 6 shows a conventional coating device of (a) spray type nozzle and (b) dot type nozzle.

[Explanation of symbols]

1 ... (masking agent) coating device 1a ... Tip surface 1b ... protrusion 2 ... Discharge port 3 ... Plate-shaped member (printed circuit board) 3a ... Application surface 3b ... Non-coated surface 4 ... Mask device 4a ... Tip 4b ... projection

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) B05D 1/32 B05D 1/32 A 5E314 H05K 3/28 H05K 3/28 B EF term (reference) 4D073 AA01 BB03 CA16 DB03 DB10 DB12 DB32.

Claims (6)

[Claims] 1. A masking agent application method for applying a liquid masking agent to the surface of a flat plate-shaped member such as a printed circuit board, wherein a tip end surface of a coating device including a masking agent discharge port faces the surface of the flat plate-shaped member. And is formed flat so that the tip end surface covers the application surface of the flat plate-like member and is arranged with a predetermined gap between the flat plate-like member and the surface of the flat plate-like member to cause a capillary action. A masking agent applying method, which comprises injecting a masking agent into the gap from the discharge port. 2. A projection is formed on the outer peripheral edge of the tip end surface of the coating device, and a gap is formed between the coating surface and the tip end surface formed by bringing the projection into contact with the surface of the flat plate-shaped member. The masking agent application method according to claim 1, wherein a masking agent is injected from the discharge port. 3. A masking agent coating device for coating a liquid masking agent on the surface of a flat plate-shaped member such as a printed circuit board, wherein the tip end surface of the coating device including a masking agent discharge port is flat. It is formed to be flat so as to face the surface, and has a structure in which the tip end surface covers the application surface of the flat plate-like member and causes a capillary action between the tip end surface and the application surface. A masking agent application device characterized in that 4. The masking agent application device according to claim 3, wherein a protrusion is formed on an outer peripheral edge of the tip surface. 5. A masking method for preventing a masking agent from adhering to a non-coated surface of a flat plate-shaped member when the liquid masking agent is applied to the surface of a flat plate-shaped member such as a printed circuit board. While covering the non-coated surface of the flat plate-like member, the projection formed on the outer peripheral edge of the surface of the mask device facing the flat plate-like member causes a capillary action between the surface of the flat plate-like member. A masking method, wherein a masking agent is injected into the coated surface of the flat plate-shaped member in a state where the masking agent is held below a gap that causes it. 6. A mask device for preventing the masking agent from adhering to a non-coated surface of the flat plate-shaped member when the liquid masking agent is applied to the surface of the flat plate-shaped member such as a printed circuit board. A projecting portion is formed on an outer peripheral edge of a surface of the mask device facing the flat plate-like member, and when the masking agent is applied to the flat plate-like member, a non-application surface of the flat plate-like member is applied by the mask device. A mask device characterized by covering.