JP2000100838A - Printing mask - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely form a protection film for protecting an integrated circuit and the like, which are mounted on a printed board by making the opening part of a printing mask to be mesh structure. SOLUTION: Epoxy resin 8 moves on a base part 3 by a stage 9, and an opening part 2 is filled with it. The stage 9 is depressed to a printing mask 1 with prescribed pressure and drops lower than a main face 1a of the base part 3 in the opening part 2, when the stage moves above the opening part 2. Since a net-like part 4 is made in the opening part 2 in the printing mask 1, the stage 9 is prevented from dropping lower than the net-like part 4 even if it drops into the recessed part 2. Thus, the stage 9 moves above the opening part 2, in a state where it is not brought into contact with an integrated circuit 5 and gold wires 7, which are positioned in the opening part 2. Consequently, a protective film can be formed surely without damaging the integrated circuit 5 and the gold wires 7, which are mounted on a printed board 6.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing mask used for printing an epoxy resin or the like on a desired area on a printed circuit board.

[0002]

2. Description of the Related Art Generally, an integrated circuit or the like is mounted on a printed circuit board using gold wires. On a printed circuit board on which such an integrated circuit or the like is mounted, the integrated circuit or the like may be covered with an epoxy resin or the like to protect the integrated circuit or the like. That is, when a printed circuit board is manufactured, a protective layer is formed by covering the integrated circuit with an epoxy resin in order to protect the integrated circuit from a solvent, an unexpected impact, or the like. Also, a protective layer may be formed on a manufactured printed circuit board by covering the integrated circuit with an epoxy resin or the like.

In forming the protective layer of the epoxy resin, a so-called printing method is used. In this printing method, a printing mask 100 as shown in FIG. 4 is used. This printing mask 100 is formed on a substantially flat plate,
It has an opening 101 formed substantially in the center.

In this printing method, first, a printing mask 100 is placed on a printed substrate 102 which is a printing object.
At this time, the printing mask 100 is placed on the printed circuit board 102 such that the integrated circuit faces the opening 101. Then, the squeegee 103 is moved in the direction of arrow a in FIG. 4 to fill the opening 101 formed in the printing mask 100 with the epoxy resin 104. After that, the printing mask 100 is removed from the printed board 102, and the epoxy resin 104 is cured.

[0005]

When a protective layer is formed using the above-described printing mask 100, a squeegee 103 is required to fill the opening 101 with the epoxy resin 104 or the like without fail. Is pressed against the printing mask 100 with a predetermined pressure, and the squeegee 103 is moved in the direction of arrow a in FIG. However, squeegee 1
03 is made of an elastic material such as rubber, and is moved while being pressed against the printing mask 100 with a predetermined pressure. was there.

As described above, when the squeegee 103 falls into the opening 101 of the printing mask 100, the squeegee 103 may come into contact with the integrated circuit.
Further, when the squeegee 103 comes into contact with the gold wire connecting the printed circuit board 102 and the integrated circuit, the gold wire may be cut.

As described above, conventionally, when a protective layer is formed using the printing mask 100, the printed circuit board 102
In some cases, an integrated circuit, a gold wire, or the like mounted on the device may be damaged. For this reason, the conventional printing mask 100 has a problem that a protective film that covers the integrated circuit cannot be reliably formed.

In view of the above, the present invention has been made in view of the above-mentioned problems, and has a printing mask capable of reliably forming a protective film for protecting an integrated circuit or the like mounted on a printed circuit board. The purpose is to provide.

[0009]

SUMMARY OF THE INVENTION A printing mask according to the present invention which has solved the above-mentioned problems has an opening, and the printing mask is positioned and placed on a printing area of a substrate to be printed. In the mask for use, the opening has a mesh structure.

[0010] In the printing mask according to the present invention configured as described above, since the openings have a mesh structure,
A squeegee or the like is prevented from falling into the opening.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of a printing mask according to the present invention will be described below in detail with reference to the drawings.

As shown in FIG. 1, a printing mask 1 according to the present embodiment is formed in a substantially plate shape, and has a substantially rectangular opening 2 at a substantially central portion thereof. In other words, the printing mask 1 has a base portion 3 having one main surface 1a formed as a flat surface.
An opening 2 is formed substantially at the center. In the printing mask 1, the inside of the opening 2 has a mesh structure. That is, the printing mask 1 includes a mesh portion 4 formed inside the opening 2.

In the printing mask 1, the mesh portion 4 having a mesh structure is formed integrally with the base portion 3, as shown in FIG. That is, the printing mask 1
In the example, the mesh portion 4 having a mesh structure is formed by forming a plurality of minute holes in a matrix.

The printing mask 1 according to the present embodiment configured as described above is used when forming a protective film on an integrated circuit mounted on a printed board. At this time,
The printing mask 1 is used by being mounted on a printed circuit board 6 on which an integrated circuit 5 is mounted, as shown in FIG. Here, the integrated circuit 5 is connected to the printed circuit board 6 with gold wires 7.
Has been implemented via More specifically, the integrated circuit 5 is mounted on a printed circuit board 6, and one end of a gold wire 7 is connected to the upper surface 5a.

The above-described printing mask 1 is placed on a printed circuit board 6 so as to house the integrated circuit 5 in the opening 2. At this time, the printing mask 1 is
And the gold wire 7 is accurately positioned and placed so as not to contact the gold wire 7. Therefore, in the printing mask 1, the opening 2 is preferably formed to be slightly larger than the integrated circuit 5.

As described above, by making the opening 2 slightly larger than the integrated circuit 5, when the printing mask 1 is placed at a predetermined position, the wall surface constituting the opening 2 and the gold wire 7 are formed.
Can reliably be prevented from coming into contact with the object.

The printing mask 1 is connected to the printed circuit board 6.
The epoxy resin 8 is dropped on one end of the base 3 while being placed on the base. Thereafter, the squeegee 9 is pressed against the printing mask 1 with a predetermined pressure, and the squeegee is moved in this state as shown in FIG.
Move in the direction of the middle arrow a. As a result, the epoxy resin 8
Is moved on the base 3 by the squeegee 9 and is filled in the opening 2.

At this time, since the squeegee 9 is pressed against the printing mask 1 with a predetermined pressure, the squeegee 9 falls below the main surface 1 a of the base 3 in the opening 2 when moving on the opening 2. However, in this printing mask 1, the opening 2
, The squeegee 9 does not fall below the mesh 4 even if the squeegee 9 falls into the opening 2. Therefore, this printing mask 1
In, the squeegee 9 moves on the opening 2 in a state of not contacting the integrated circuit 5 and the gold wire 7 located in the opening 2.

As described above, when the above-described printing mask 1 is used, the protective film is formed without the squeegee 9 coming into contact with the integrated circuit 5 or the gold wire 7. Therefore, with this printing mask 1, it is possible to reliably form the protective film without damaging the integrated circuit 5 and the gold wires 7 mounted on the printed board 6.

When the printing mask 1 is used, the stress applied to the gold wire 7 can be greatly reduced when the particle size of the material forming the epoxy resin 8 becomes small. . In other words, in the printing mask 1, since the stress applied to the gold wire 7 can be reduced, the epoxy resin 8 made of a material having a small particle size can be used. in this case,
In particular, the protective film can be printed uniformly.

The printing mask according to the present invention comprises:
The present invention is not limited to the printing mask 1 shown in the above-described embodiment. For example, the mesh 4 in the opening 2 may be formed as a separate member. That is, the printing mask 1 includes, for example, a net-like portion 4 made of metal or the like.
May be mounted in the opening 2 formed in the base 3. In this case, the printing mask 1
Can be formed, for example, by insert-molding a metal net-like portion 4.

Even when the printing mask 1 is used, the squeegee 9 does not come into contact with the integrated circuit 5 or the gold wire 7,
A protective film can be formed. Therefore, even with this printing mask 1, it is possible to reliably form the protective film without damaging the integrated circuit 5 and the gold wires 7 mounted on the printed board 6.

Further, as described above, the printing mask according to the present invention is not limited to the mask used when forming the protective film using the epoxy resin 8, but may be, for example, a solder paste. It can also be used when printing solder paste on an area.

[0024]

As described in detail above, since the printing mask according to the present invention has a mesh structure in the opening, a squeegee falls into the opening, and an integrated circuit or the like arranged in the opening is removed. Damage is reliably prevented. Therefore, with this printing mask, a protective film or the like can be reliably formed by printing.

[Brief description of the drawings]

FIG. 1 is a plan view of a printing mask shown as an embodiment of the present invention.

FIG. 2 is an enlarged plan view showing a main part of a mesh structure of a printing mask.

FIG. 3 is a cross-sectional view showing a state in which a protective film is formed using a printing mask.

FIG. 4 is a perspective view showing a state in which a protective film is formed using a conventional printing mask.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Printing mask 2 Opening 3 Base part 4 Net-like part 5 Integrated circuit 6 Printed circuit board 7 Gold wire 8 Epoxy resin 9 Squeegee

Claims (1)

[Claims] 1. A printing mask having an opening, wherein the opening is positioned on a printing area of a substrate to be printed and placed thereon, wherein the opening has a mesh structure. For mask.