1. Field of the Invention
This invention relates to a plastic film capacitor.
2. Prior Art
Miniaturization of electric and electronic instruments depends largely the high packaging density of the circuit. Developments in chip electronic components have positively been promoted for the purpose of high density packaging and standardization of process. Various chip capacitors have also been developed, especially in the field of ceramic capacitors. However, no chip film capacitors capable of withstanding soldering have been put into practical use, because the plastic film constituting the dielectric has a lower heat resistance. The films used now in film capacitors will entirely be molten or extremely deformed at a high temperature of 220.degree. C. to 260.degree. C. Hence, such fatal defects were inherent in that, during the soldering, an element is largely deformed, a short circuit occurs between the electrodes, and capacity remarkably varies. On the other hand, commercially available films are so large in thickness that the element will be large-sized in order to get the necessary electric capacity, and too large in dielectric tangent or too high in manufacturing cost to be used alone as a capacitor.
A laminated capacitor conventionally has been proposed in U.S. Pat. No. 3,654,532, which targets a usual package system having lead wires, but no considerations have been taken concerning the heat resistance of the capacitor which has no lead wire and is soldered directly onto the substrate. Hence, the heat resistance of the film and dielectric are not at all referred to.