JPS5930545Y2 - printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a printed wiring board, and particularly to marking printing for clearly indicating the position, shape, etc. of electronic components on which electronic components are mounted.

Conventionally, on printed wiring boards, where it is necessary to specify the mounting position of electronic components, directionality measurement terminals, etc., symbols of a specific shape or alphanumeric characters are placed on the surface of the printed wiring board in the vicinity of the positions where they should be specified. The remaining characters may be displayed as a screen-printed pattern in blue, etc., or by etching the symbols as part of the wiring conductor pattern.
Or, it is usually displayed as a pattern.

On the other hand, when soldering electronic components, etc., a heat-resistant organic film commonly known as solder resist is used to protect the surface of wiring boards in order to improve workability during mounting. In advance, the solder resist is printed on a printed wiring board, and printed characters or patterns are printed on the layer using ink of a different tone from that of the underlying solder resist.

Otherwise, the actual situation as shown in Figure 1
740, which has a reddish-brown base material such as Bakelite as a base material, in order to reduce the number of steps required for two-time printing, a solder with a color composition that stands out in color contrast with the base material, such as green solder resist 1, is used. There is also a method commonly known as cut-out characters that uses resist ink to display numbers 2, arrows 3, English letters 4, or designated patterns on the solder resist 1 in the shape of the unprinted parts of the solder resist. .

However, in the conventional method described above, when character printing and solder resist printing are separately printed twice, the number of man-hours is increased in both the pre- and post-processing and printing steps of solder resist printing, which inevitably increases the number of man-hours.

In addition, in the second method, when symbols are displayed using cutout letters or cutout patterns of solder resist, the reddish-brown tone of Bakelite, etc. of the printed wiring board base material, and the green tone of solder resist, etc. are used. As in the example,
If there is a fairly clear difference in color tone, there is not much of a problem in distinguishing between the two, but in recent years, with the improvement in component mounting density of printed wiring boards, epoxy glass and other materials such as through-hole plating printed wiring boards and multilayer through-hole plating printed wiring boards have improved. When using a base material, the color tone of the base material itself is pale green, and furthermore, display characters and the like must be displayed using thin lines.

For this reason, with the cut-out character method, there is almost no difference in color tone,
Difficult to distinguish unless observed very carefully.

In addition, characters tend to disappear due to printing fog or bleeding, and it is particularly difficult to print fine line characters of Q and 1 mm or less.

Furthermore, when components are mounted on a printed wiring board, the characters are recessed below the surface of the solder resist, so flux tends to accumulate in the soldering parts, making the characters difficult to read.

An object of the present invention is to provide a printed wiring board that eliminates such drawbacks.

That is, the printed wiring board according to the present invention has a single or a plurality of non-printing openings in a solder resist baton applied to the surface of the board, and alphanumeric characters or display elements of a certain shape are formed in the solder resist in the openings. It is characterized by having been established.

An embodiment of the present invention will be described below with reference to FIG.

FIG. 2 is an embodiment of the present invention, and shows the pattern shape after screen printing with heat-resistant epoxy resin ink is performed on the surface of a printed wiring board manufactured by a conventional printing and etching method.

As is clear from FIG. 2, the present invention provides a window frame-shaped non-printing part 5 of a fixed shape in the solder resist pattern,
A symbol for displaying parts, that is, a display element is written into the window frame-like non-printing part 5 using solder resist, and the shape of the display element makes it readable as a positive pattern, that is, a pattern protruding from the substrate surface. It is in.

According to the present invention, this display element becomes a distorted plate printed character, so
Even fine lines with a width of 0.05 to Q, 1Q mm can be faithfully printed, resulting in a fine pattern with no printing fog.

Furthermore, a window frame part of a certain shape is provided, and there is a gap between the solder resist of the display part and the display element, so that the operator can place the part where the display element is located between the base material and the solder resist. Even if the colors are similar, they have the advantage that they can be easily distinguished because of the window frame-like steps.

In addition, since the display elements (characters) are not stuck to the surface of the solder resist, even when components are mounted on a printed wiring board, soldering flux does not accumulate in the display elements, and the display elements do not become difficult to read.

Furthermore, since solder resist and symbol printing can be performed simultaneously, it is advantageous in terms of manufacturing man-hours.

Furthermore, the window frame-shaped solder resist also prevents the display element from being damaged by external forces or becoming unreadable due to wear and tear, and it is important to note that it achieves a long-life display function. There is no advantage.

The content of the present invention has been explained above with reference to an embodiment of the present invention.The present invention has an extremely simple configuration, greatly reduces the number of manufacturing steps, and has printed wiring with display elements that are extremely free from human error. It has the effect of providing a board.

[Brief explanation of drawings]

FIG. 1 is a plan view of the main parts of a conventional printed wiring board, and FIG. 2 is a plan view of the main parts of an embodiment of the present invention. Codes in the diagram 1: Solder register), 2, 12: Number,
3.13: Symbols such as arrows, 4, 14: English letters, 5:
Non-printed part shaped like a window frame.

Claims (1)

[Scope of utility model registration request] For soldering, a non-printed part in the shape of a window frame of a certain shape is provided in the solder resist pattern applied to the wiring conductor pattern and the surface of the board, except for the parts, and a predetermined display element made of the solder resist is placed in the non-printed part. A printed wiring board characterized by being provided so as to protrude from the surface of the substrate.