Wired circuit board and production method thereof

Abstract

A wired circuit board includes an insulating base layer, a conductive pattern formed on the insulating base layer, and an insulating cover layer formed on the insulating base layer for covering the conductive pattern. The conductive pattern includes terminal portions for connecting with external terminals. The insulating cover layer has an opening formed correspondingly for the respective terminal portions. A position determining zone for determining whether or not a margin of the insulating cover layer facing the opening is located in a proper position is provided in proximity of the terminal portions.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

In the drawings:

FIG. 1( a) is an enlarged plan view showing a mounting area of an embodiment of a wired circuit board of the present invention (in the state that terminal portions of an insulating cover layer are placed in position determining zone), and FIG. 1(b) is an enlarged sectional view of the mounting area of the wired circuit board taken along line A-A shown in FIG. 1(a),

FIG. 2 is a production process drawing showing a producing method of the wired circuit board shown in FIG. 1(b),

(a) showing the process of preparing an insulating base layer,

(b) showing the process of forming both a conductive pattern and determining mark simultaneously on the insulating base layer,

(c) showing the process of forming an insulating cover layer on the insulating base layer so that an insulating cover layer is formed with an opening in the insulating cover layer, and

(d) showing the process of forming a metal plating layer on terminal portions exposed from the opening of the insulating cover layer, on their respective wires, and on each pair of determining marks,

FIG. 3 is an enlarged plan view of a marginal portion of the insulating cover layer on a side of the opening in the wired circuit board shown in FIG. 1(a),

FIG. 4 is an enlarged plan view corresponding to FIG. 3, showing another embodiment of the pair of determining marks (determining marks in a square form, as viewed from top, formed on dedicated wires),

FIG. 5 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a square form, as viewed from top, separated from the wires),

FIG. 6 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a triangular form, as viewed from top, separated from the wires),

FIG. 7 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a plus sign shape, as viewed from top, separated from the wires),

FIG. 8 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a minus sign shape, as viewed from top, separated from the wires),

FIG. 9 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a T shape extending along a longitudinal direction of the wire, as viewed from top, separated from the wires),

FIG. 10 is an enlarged plan view corresponding to FIG. 3, showing a still another embodiment of the pair of determining marks (determining marks in a T-shape extending along a margin of the insulating cover layer, as viewed from top, separated from the wires),

FIG. 11 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in an L-shape, as viewed from top, separated from the wires),

FIG. 12 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a circular form, as viewed from top, separated from the wires),

FIG. 13 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks in a generally rectangular form, as viewed from top, extending continuously with the wires),

FIG. 14 is an enlarged plan view corresponding to FIG. 3, showing still another embodiment of the pair of determining marks (determining marks extending continuously with the wires and cut off in a square form as viewed from top), and

FIG. 15 is an enlarged plan view showing the mounting area of the embodiment of the wired circuit board shown in FIG. 1(a) (in the state that margins of the insulating cover layer are not placed in the position determining zone).

Claims

1. A wired circuit board comprising: an insulating base layer; a conductive pattern formed on the insulating base layer; andan insulating cover layer formed on the insulating base layer for covering the conductive pattern,wherein the conductive pattern includes terminal portions for connecting with external terminals;the insulating cover layer has an opening formed correspondingly for the respective terminal portions; anda position determining zone for determining whether or not a margin of the insulating cover layer facing the opening is located in a proper position is provided in proximity of the terminal portions.

2. The wired circuit board according to claim 1, wherein the position determining zone is formed to extend along a direction of the margin of the insulating cover layer, and the position determining zone is defined by a pair of determining marks which are disposed opposite to each other in a direction intersecting with the direction along the margin of the insulating cover layer and are spaced apart by an amount to allow tolerance to an area where the margin of the insulating cover layer is formed.

3. The wired circuit board according to claim 2, wherein a plurality of terminal portions are arranged in parallel along the direction of the margin of the insulating cover layer, the conductive pattern includes wires extending from the terminal portions in the direction intersecting with the direction along the margin of the insulating cover layer correspondingly to the respective terminal portions, and the determining marks are located outside of the wires arranged at outermost sides of the direction extending along the margin of the insulating cover layer.

4. The wired circuit board according to claim 2, wherein the determining marks are projected outward from the wires arranged at both outermost sides of the direction extending along the margin of the insulating cover layer.

5. A production method of a wired circuit board, comprising the steps of: forming a conductive pattern including terminal portions for connecting with external terminals on an insulating base layer;forming an insulating cover layer on the insulating base layer to cover the conductive pattern so that an insulating cover layer is formed with an opening from which the terminal portions are exposed;forming a position determining zone for determining whether or not a margin of the insulating cover layer facing the opening is located in a proper position; anddetermining whether or not the margin of the insulating cover layer is located in a proper position,wherein in the step of determining whether or not the margin of the insulating cover layer is located in a proper position, when the margin of the insulating cover layer is within the position determining zone, the wired circuit board is determined to be non-defective, while when the margin of the insulating cover layer is out of the position determining zone, the wired circuit board is determined to be defective.

6. The production method of the wired circuit board according to claim 5, wherein in the steps of forming the conductive pattern and forming the position determining zone, the conductive pattern and the position determining zone are formed simultaneously.