JPH11307890A - Printed wiring board - Google Patents

Abstract

(57) [Problem] To provide a printed wiring board provided with a mark capable of visually confirming a shift between a wiring pattern of the printed wiring board and a solder resist on the wiring pattern. SOLUTION: Cross-shaped metal patterns 3a to 3e and a cross-shaped solder resist 4 on the metal patterns 3a to 3e are formed at corners of the printed wiring board where no wiring pattern is formed.
A shift confirmation mark 2 composed of individual confirmation marks 2a to 2e formed by a to 4e is provided. The metal pattern 3a depends on the degree of displacement between the wiring pattern and the solder resist.
3e are exposed from the solder resists 4a to 4e. By visually observing the exposed portions, a shift between the metal pattern and the solder resist can be confirmed.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printed wiring board for easily confirming a wiring pattern of a printed wiring board or a displacement between a land and a solder resist.

[0002]

2. Description of the Related Art As a pre-treatment when soldering a component to a printed wiring board, a solder resist is formed at a place where soldering is unnecessary in order to prevent a flow of solder to a place where soldering is not required. Is done. Normal,
A solder resist is formed by a printing method or a photoresist method so that the wiring pattern is not exposed on the wiring pattern except for the lands to which the components of the printed wiring board are soldered, thereby protecting the wiring pattern. Therefore, it is necessary to ensure that the wiring pattern is not exposed and that the displacement of the solder resist to the land (land fog) does not exceed an allowable range.

[0003]

Conventionally, the displacement between the wiring pattern and the solder resist has been confirmed with a microscope. In this confirmation work, a plurality of printed wiring boards with solder resist formed on the wiring pattern were sampled and the deviation between the wiring pattern and the solder resist was confirmed, and the tendency of the deviation dimension and deviation direction was grasped, Actually, this is an operation that requires time and effort on a production line. In particular, for high-density mounting printed wiring boards,
Since the allowable range of the displacement dimension is narrow, it is more difficult to confirm the displacement.

An object of the present invention is to provide a printed wiring board in which a deviation between a wiring pattern and a solder resist can be easily confirmed visually or the like.

[0005]

According to the present invention, there is provided a printed wiring board comprising a metal pattern and a solder resist formed on the metal pattern in a region where the wiring pattern is not formed. A shift confirmation mark for checking the shift is provided. If there is a shift between the wiring pattern and the solder resist, the metal pattern of the shift check mark and the solder resist also shift and the metal pattern is exposed, so that the shift can be confirmed by the metal color of the exposed metal pattern.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described with reference to FIGS. FIG. 1 shows a displacement confirmation mark 2 (hereinafter referred to as a confirmation mark 2) disposed at a predetermined position of a printed wiring board 1, at least two corners, for example, four corners.
). As shown in FIG. 1, when manufacturing the printed wiring board 1, a cross-shaped metal pattern is printed on the printed wiring board 1 in advance at the same time when the lands to which the electronic components are soldered and the wiring pattern are printed. The cross-shaped metal patterns constituting the confirmation mark 2 are, for example, five sets of metal patterns 3a, 3b, 3c, 3d as shown in the figure.
And 3e are printed in a line at a corner on the printed wiring board 1. Below each metal pattern, a numerical range 7 of the displacement dimension is described by a metal pattern or silk paint as described later.

Here, the metal patterns 3a to 3e are:
When printed at the same time as the wiring pattern, the wiring pattern is made of the same material as the wiring pattern, but a metal such as silver or aluminum that can be visually confirmed in a good color can be printed and printed in a later step. You can also. These cross-shaped metal patterns 3a to 3e are connected to the metal patterns 3a to 3e in a later step as shown in FIG.
Solder resists 4a, 4b, 4c, 4 formed thereon
The individual confirmation marks 2a to 2e are formed by d and 4e, and constitute a confirmation mark 2 for visually confirming a displacement dimension and a displacement direction between the metal pattern and the solder resist on the metal pattern. The deviation between the wiring pattern and the solder resist formed on the wiring pattern can be known only by checking the deviation between the metal pattern and the solder resist formed on the metal pattern.

Here, the solder resist forming method is roughly divided into two methods, a printing method and a photoresist method. In particular, in a printing method, a printing screen mask, and in a photoresist method, expansion and contraction of a photosensitive film and displacement of a mounting position occur, so that a positional displacement at both ends of a printed wiring board may become remarkable. Therefore, if the metal pattern is arranged on at least two corners of the printed wiring board 1 at large intervals, for example, four corners, the positional deviation can be confirmed with high accuracy by visual inspection or the like.

[0009] The metal patterns 3a to 3
By visually confirming the displacement between the solder resist 3e and the solder resists 4a to 4e, the displacement of the solder resist on the land from the allowable range, the displacement amount between the solder resist and the wiring pattern on the wiring pattern and The direction of the shift can be confirmed. The metal patterns 3a to 3a
e, the solder resists 4a to 4e are surrounded by a frame line 5 of pattern data or silk paint, so that a place where the confirmation mark 2 is present can be easily searched.

Next, FIG. 2A shows a cross-shaped solder resist 4 having a width A formed on the metal pattern 3 having a width B, and showing a state where there is no misalignment between them. I have. As shown in FIG. 2A, the width A of the solder resist
Is set to be larger than the width B of the metal pattern 3, if there is no displacement between the two, the metal pattern 3 is completely covered with the solder resist 4, and the metal color of the metal pattern 3 cannot be visually confirmed.

On the other hand, FIG. 2B shows a state in which the metal pattern 3 and the solder resist 4 are shifted. FIG.
As shown by hatching in (B), the metal pattern exposed portion 6 where the metal pattern 3 protrudes from the solder resist 4 is:
Since the metal pattern 3 is not covered with the solder resist 4, the metal pattern 3 shines in a metal color. By visually checking the exposed portion 6, it is possible to check in which direction and how much the solder resist 4 is displaced from the metal pattern 3.

Hereinafter, a specific example of confirming the direction of the shift and the degree of the shift visually will be described with reference to FIGS. As shown in FIG. 3, the width A of the solder resist,
With the width A of the solder resist fixed as the width B of the metal pattern, the one with A = B = 1.0 mm is individually confirmed at the position of the individual confirmation mark 2a, and the one with B = A−0.1 mm = 0.9 mm. At the position of the mark 2b, B = A−0.2 mm =
0.8 mm at the position of the individual confirmation mark 2c, B =
A-0.3mm = 0.7mm individual confirmation mark 2
At the position of d, the one with B = A-0.4 mm = 0.6 mm is arranged at the position of the individual confirmation mark 2e, and the confirmation mark 2 is constituted by the individual confirmation marks as a whole.

In the following, a method for confirming the displacement and the direction of displacement of the solder resists 4a to 4e when the solder resists 4a to 4e are formed with the above-mentioned dimensions respectively on the metal patterns 3a to 3e will be described. For example, assume that the metal pattern 3 and the solder resist 4 are shifted by 0.15 mm.

In the confirmation mark 2, when the solder resist formed on each metal pattern is displaced by 0.15 mm when the solder resist is applied to the printed wiring board, the individual confirmation marks 2a, 2b, and 2c become three. Are
Since the metal patterns 3a, 3b, and 3c are exposed from the solder resists 4a, 4b, and 4c, the exposed portions can be visually confirmed. Therefore, the range of the misalignment dimension can be confirmed by which individual confirmation mark of the individual confirmation marks 2a, 2b, 2c, 2d, and 2e is exposed.

When the widths of the metal patterns 3a to 3e and the solder resists 4a to 4e are set as described above (paragraph number 0012), specific deviation dimensions can be visually confirmed as follows. (1) When the exposure of the metal pattern is not confirmed to the individual confirmation marks 2a to 2e, the shift amount is 0.0 mm. (2) When the exposure of the metal pattern can be confirmed only with the individual confirmation mark 2a, the shift amount is larger than 0.0 mm and 0.0
5 mm or less. (3) When the exposure of the metal pattern of the individual confirmation marks 2a and 2b can be confirmed, the deviation amount is larger than 0.05 mm and 0.1 mm or less. (4) When the exposure of the metal pattern of the individual confirmation marks 2a to 2c can be confirmed, the shift amount is larger than 0.1 mm and 0.15 mm or less. (5) When the exposure of the metal pattern of the individual confirmation marks 2a to 2d can be confirmed, the deviation amount is larger than 0.15 mm and 0.2 mm or less. (6) When the exposure of the metal pattern of the individual confirmation marks 2a to 2e can be confirmed, the deviation amount is larger than 0.2 mm.

As described above, the amount of deviation between the metal pattern of each individual confirmation mark and the solder resist can be confirmed. If the actual deviation is as shown in FIG. It is clear that the direction can be confirmed. In the case of FIG. 2B, it can be seen that the direction of displacement of the solder resist 4 with respect to the metal pattern 3 is obliquely on the upper left.

In the above embodiment, the plurality of individual confirmation marks have the same solder resist width as each other and the configuration in which the widths of the metal patterns are different from each other. It is also possible to change the widths of the solder resists.

Although the cross shape is adopted as the shape of the metal pattern and the solder resist of the confirmation mark, any shape can be adopted as long as it can confirm the positional deviation and the direction of the deviation. For example, a circle can be adopted as another shape that can confirm the position shift and the direction of the shift.

In the case of a circular shape, the confirmation mark may be composed of a plurality of individual confirmation marks formed of a circular metal pattern having the same radius as each other and a circular solder resist having a radius different from each other, or different from each other. The present invention can also be implemented by a plurality of individual confirmation marks each formed of a circular metal pattern having a radius and a circular solder resist having the same radius.

Also, if the difference between the width and the radius of the metal pattern and the solder resist is reduced, the deviation can be confirmed in finer steps, and if the difference is increased, the deviation can be confirmed in larger steps. If the confirmation mark is created by using the method, it is possible to support a printed wiring board from low-density mounting to high-density mounting.

[0021]

According to the present invention, the shift between the wiring pattern and the solder resist can be easily checked simply by checking the shift between the metal pattern of the check mark and the solder resist, and the checking work efficiency is improved. .

[Brief description of the drawings]

FIG. 1 is a plan view of a main part of a confirmation mark of the present invention.

FIG. 2 is an explanatory diagram of a check mark according to the present invention with and without shift.

FIG. 3 is an explanatory diagram of an individual confirmation mark constituting the confirmation mark of the present invention.

[Explanation of symbols]

1. Printed wiring board 2. Misalignment confirmation mark 2a ~
2e ··· Individual confirmation mark 3,3a-3e ·· Metal pattern 4,4a-4e ·· Solder resist

Claims (8)

[Claims] 1. A shift confirmation mark for confirming a shift between a metal pattern and a solder resist, which is formed by a metal pattern and a solder resist on the metal pattern, in a region of the printed wiring board where the wiring pattern is not formed. A printed wiring board, comprising: 2. The printed wiring board according to claim 1, wherein the misalignment confirmation marks are arranged at at least two corners on the printed wiring board. 3. The printed wiring board according to claim 1, wherein the metal pattern and the solder resist forming the misalignment confirmation mark are a cross-shaped metal pattern and a cross-shaped solder resist. 4. The printed wiring board according to claim 1, wherein the metal pattern and the solder resist forming the misalignment confirmation mark are a circular metal pattern and a circular solder resist. 5. The shift confirmation mark comprises a plurality of individual confirmation marks formed by a cross-shaped metal pattern having the same width as each other and a cross-shaped solder resist having a width changed from each other. The printed wiring board according to claim 3. 6. The shift confirmation mark comprises a plurality of individual confirmation marks respectively formed of a cross-shaped metal pattern having a width changed from each other and a cross-shaped solder resist having the same width as each other. The printed wiring board according to claim 3. 7. The shift confirmation mark comprises a plurality of individual confirmation marks respectively formed by a circular metal pattern having the same radius as each other and a circular solder resist having a radius different from each other. Item 4. The printed wiring board according to Item 4. 8. The shift confirmation mark comprises a plurality of individual confirmation marks formed of a circular metal pattern having a radius different from each other and a circular solder resist having the same radius as each other. Item 4. The printed wiring board according to Item 4.