METHOD OF INSULATING WIRING PATTERN OF PRINTED CIRCUIT BOARD AND FIRE SENSOR HAVING PRINTED CIRCUIT BOARD, WHOSE WIRING PATTERN BEING INSULATED BY THE SAME

摘要

PROBLEM TO BE SOLVED: To improve insulation of a cut portion of a wiring line and to prevent adhesion of moisture and corrosion on the cut surface. SOLUTION: On a surface of an insulation base 101 wiring lines 102 are formed, which are made of copper foil and connected with each other at a connection branch 104, and solder resist 103 protecting the wiring lines 102 is laminated to compose a printed circuit board 100. A desired wiring pattern is obtained by punching a portion including a certain connection branch 104 to provide a through-hole 105 penetrating the printed circuit board 100 and cutting unnecessary wiring lines 102. Circuit components and the through-hole 105 are simultaneously sealed by sealing material 106 made of synthetic resin having insulation property, and the cutting portion and cutting surface of the wiring lines 102 exposed to the through-hole 105 are protected by the sealing material 106. Therefore, insulation property of the cutting portion of the wiring lines 102 is improved and adhesion of moisture and corrosion on the cut surface can be prevented. COPYRIGHT: (C)2008,JPO&INPIT