In late years, CO2 released into the atmosphere is required to reduce for prevention of global warming. There is a suggestion on adoption of a solar system using a silicon based solar battery of pn junction type as one embodiment of electronic devices. However, monocrystal silicon, polycrystal silicon and amorphous silicon as materials of a silicon based solar battery need high temperature and high vacuum processes in production thereof.
In contrast, for an organic film solar battery containing an organic layer containing a polymer compound, high temperature and high vacuum processes used for production of a silicon based solar battery can be omitted, thus, the organic film solar battery can possibly be produced at low cost via only an application process, and is attracting attention recently. As a polymer compound used in an organic film solar battery, a polymer compound composed of a repeating unit (A) and a repeating unit (B) is known (Patent document 1).

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