Photosensitive elements used for making a printed circuit board usually have a form of a laminated film in which a layer of photosensitive resin composition is sandwiched between a support film and a protective film. Upon their use, the layer of photosensitive resin composition is laminated on a circuit-forming substrate while peeling off the protective film. After being selectively irradiated with ultraviolet rays by way of a predetermined mask, the layer is subjected to a development process, so as to form an image on the printed circuit board.
USPTO Backgrounds
USPTO Backgrounds