JPS63175495A - Printed wiring board and manufacture of the same - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] [Industrial application field] The present invention relates to a printed wiring board and a method for manufacturing the same.

[Conventional technology]

Conventionally, the external shape and shape of insulating substrates have been When processing the end face of the elongated hole into a smooth surface, the end face of the elongated hole is punched out one by one using a punching fin method using a press, leaving the finished dimensions of the outer shape.
Second. The third mold is divided into several batches to gradually form the finished size, or the finished size is formed by cutting using a router bit or the like.

[Problem that the invention seeks to solve]

As mentioned above, the conventional processing of printed wiring boards involves recessing, so the glass fibers of the insulating substrate become whiskers and remain on the outer shape of the insulating substrate and the end faces of the long holes during the various finishing treatments performed after forming. Dust adheres during the process of mounting electronic components and causes poor contact between electronic components. Furthermore, since several punches are required during the fin removal process, the mold cost is high. Furthermore, when machining is performed using a router bit, etc., it requires a lot of machining time to uniformly raise each end face to create a smooth surface. There were problems such as that it was not suitable for printed wiring boards that required portions to have rounded corners.

An object of the present invention is to provide a printed wiring board that is suitable for wiring, which eliminates poor contact between electronic components, is inexpensive, requires less processing time, and is suitable for wiring by coating photoresist on the outer shape of an insulating substrate and the end faces of long holes, and a method for manufacturing the same. Our goal is to provide the following.

[Means for solving problems]

The printed wiring board of the present invention includes an insulating substrate, a plurality of long holes for dividing into individual pieces that penetrate the insulating substrate and are provided at intervals parallel to one side, and that are formed in the insulating substrate by a through-hole method. In the printed wiring board, the printed wiring board includes a connecting land provided on both sides of the insulating substrate, a component mounting pad provided on both sides of the insulating substrate, and wiring connected to the connecting land and the component mounting pad. A photoresist is coated on the end face of the elongated hole.

The method for manufacturing a printed wiring board of the present invention includes a step of forming connection lands on an insulating substrate by a through-hole method, and forming a component mounting pad on both sides of the insulating substrate and wiring connected to the component mounting pad and the connection land. a step of punching out a plurality of elongated holes for dividing the insulating substrate into individual pieces in a direction parallel to the outer shape of the insulating substrate and one side; and a step of applying photoresist to both sides and end surfaces of the insulating substrate and the end surfaces of the elongated holes. and a step of irradiating the insulating substrate and the end faces of the long holes with ultraviolet rays through an exposure mask, and then performing a development process to coat the end faces of the insulating substrate and the end faces of the long holes with photoresist. It is made up of.

〔Example〕

Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing a first embodiment of the printed wiring board of the present invention.

The printed wiring board 1 has long holes 3 and V grooves 8 to separate it into individual pieces.
is provided. Photoresist is applied to the outer shape of the printed wiring board 1 and the end faces of the elongated holes 3, forming a smooth outer end face 2 and a smooth elongated hole end face 4, exposing whisker-like glass fibers to prevent poor contact between electronic components. The structure is such that it can be done.

FIGS. 2(a) and 2(b) are cross-sectional views of a printed wiring board shown in order of steps for explaining one embodiment of the method for manufacturing a printed wiring board of the present invention.

An insulating substrate 11 made of glass epoxy resin is perforated and plated to form connection lands 5, component mounting pads 6, and wiring 7.
After providing the insulating substrate 11, the outer shape of the insulating substrate 11 and the elongated holes 3 are punched out by pressing or the like to form the printed wiring board 1. A photoresist 8 is applied to both the front and back surfaces and the entire end surface of the formed printed wiring board 1, and after being irradiated with ultraviolet rays through an exposure mask, it is developed, and the outer shape of the printed wiring board 1, the end face of the long hole 3, and the component mounting are formed. By depositing photoresist 8 between the connection pad 6, the connection land 5 and the component mounting pad 6, and the connection land 5 and the component mounting pad 6, there is no contact failure of electronic components, the cost is low, and the processing time is reduced. A printed wiring board 1 suitable for wiring can be obtained.

FIG. 3 is a sectional view showing an example of a photoresist coating apparatus used in manufacturing the printed wiring board of the present invention.

A lift 14 is installed at the upper center of the dipping tank 22 to which the printed wiring board 1 pressed can be attached, and has a structure that allows it to be moved in the vertical direction. The immersion tank 22 is filled with a photoresist liquid 17, and the liquid level of the photoresist liquid 17 is kept constant by a liquid level partition plate 16.

The liquid level of the photoresist liquid 17 can be automatically adjusted by a circulation pump 18, and the photoresist liquid 17 that overflows and returns to the immersion tank 22 is treated with a diluent to keep the viscosity of the photoresist liquid 17 constant. Since it is necessary to mix, stir, and dilute, the liquid is introduced into the stirring tank 19. The stirring tank 19 has a diluent cup 20 for supplying a diluent, and the diluent is automatically supplied according to the viscosity type instruction in the dipping tank 22, and the stirring pump 21 operates to supply the diluent in the stirring tank 19. A photoresist solution 17 having a constant viscosity is obtained and circulated to the immersion tank 22 in conjunction with the circulation pump. To apply photoresist 8 to printed wiring board 1, several printed wiring boards 1 that have been pressed in advance are set in a vertical line on wiring board mounting portion 15 provided on lift 14. Next, when the lift 5 is lowered into the immersion tank 22 and stopped at a predetermined position, the circulation pump 18 is activated and the photoresist solution 17 is introduced into the immersion tank 22. When the photoresist solution 17 flows out from the liquid level partition plate 16, The lift 14 rises from the immersion bath 22 and the entire printed wiring board 1 is immersed in the photoresist solution 17. After dipping, the lift 14 is moved 90 degrees so that the photoresist solution 17 is evenly applied to the entire surface of the printed wiring board 1.
° Rotate and return to restoring position for a few minutes. After the operation of the lift 14 is completed, by removing the wiring board attachment part 15 attached to the lift 14, the printed wiring board 1 can be taken out all at once without touching it. Printed wiring board 1 taken out
The photoresist liquid 17 can be hardened by putting it in a drying oven and drying it while it is attached to the wiring board attachment part 15. In addition, for products with small production volumes and short delivery times, printed wiring boards 1 and long holes 3 should be punched out using press processing, etc.
It is also possible to apply the photoresist solution manually to the end surface of the substrate using a brush or brush.

〔Effect of the invention〕

As explained above, the present invention provides a printed wiring board by applying photoresist to the outer end face of the printed wiring board and the end face of the long hole after forming the outer frame and the elongated hole by recess processing by press punching or the like. This has the advantage that there is no contact failure of electronic components due to the exposure of whisker-like glass fibers peculiar to insulating substrates, and that a printed wiring board that is inexpensive, requires less processing time, and is suitable for wiring can be obtained.

[Brief explanation of the drawing]

FIG. 1 is a perspective view showing a first embodiment of the printed wiring board of the present invention, and FIGS. 2(a) and (b) are for explaining an embodiment of the method of manufacturing the printed wiring board of the present invention. FIG. 3 is a sectional view showing an example of a photoresist coating apparatus used in manufacturing the printed wiring board according to the present invention. DESCRIPTION OF SYMBOLS 1...Printed wiring board, 2...Smooth outer shape end surface, 3...
Elongated hole, 4... Smooth elongated hole end surface, 5... Connection land, 6
... Pad for mounting components, 7... Wiring, 8... V groove, 9... Photoresist, 10... Mask, 11...
- Insulating substrate, 12... Rough surface outer shape end surface, 13... Rough surface long hole end surface, 14... Lift, 15... Printed wiring board mounting portion, 16... Liquid level partition plate, 17. ...Photoresist solution, 18...Circulation pump, 1...Stirring tank, 20.
... Diluent cup, 21... Stirring pump, 22...
Soaking tank. l5 super sales attack department $ 3 diagram

Claims (2)

[Claims] (1) an insulating substrate, a plurality of long holes for dividing into individual pieces that penetrate the insulating substrate and are provided at intervals parallel to one side;
A printed wiring board including a connection land provided on the insulating substrate by a through-hole method, component mounting pads provided on both sides of the insulating substrate, and wiring connected to the connection land and the component mounting pad. . A printed wiring board, characterized in that a photoresist is applied to an outer end face of the printed wiring board and an end face of the elongated hole. (2) a step of forming a connection land on an insulating substrate by a through-hole method; a step of forming a component mounting pad and wiring connected to the component mounting pad and the connection land on both sides of the insulating substrate; a step of punching out a plurality of long holes for dividing into individual pieces in a direction parallel to the outer shape of the board and one side;
A step of applying photoresist to both sides and end surfaces of the insulating substrate and an end surface of the elongated hole, and a step of irradiating ultraviolet rays to the insulating substrate and the end surface of the elongated hole through an exposure mask, followed by a development process, A method for manufacturing a printed wiring board, comprising the step of applying photoresist to an end face and an end face of the elongated hole.