Abstract: A capacitor element (10) fabricated by winding an anode foil (1) and a cathode foil (2) via a separator (3) is impregnated with a 3,4-ethylenedioxythiophene and an oxidizing agent to form poly(ethylenedioxythiophene) by chemical polymerization. A nonwoven fabric composed chiefly of a synthetic fiber is used as a separator, enabling a solid electrolyte to be favorably formed without being reacted with the oxidizing agent. Preferably, the capacitor element is dipped in water at 80 to 100° C. for 1 to 20 minutes to dissolve and remove the binder in the separator in order to preclude adverse effects on the electric characteristics caused by the binder. The oxidizing agent is used at a concentration in excess of 40% by weight with respect to the solvent, so that the degree of polymerization is high and a dense and homogeneous solid electrolytic layer is formed.

Abstract: A solid electrolyte layer of dense and uniform conductive polymer is formed with a capacitor element of the wound type in order to provide a solid electrolytic capacitor of improved electric characteristics and large capacity and a process for manufacturing the same. The capacitor element (10) in which an anode foil (1) and a cathode foil (2) are wound by means of a separator (3) is impregnated with a solution mixture of 3,4-ethylendioxythiophene and an oxidizing agent so that the solution mixture is penetrated into the inside of the capacitor element (10) for the gentle polymerization reaction of 3,4-ethylendioxythiophene with an oxidizing agent during and after the impregnation in order to produce polyethylenedioxythiophene for forming a solid electrolyte layer within the capacitor element. Further, a solid electrolytic capacitor in which an electrolytic layer is sufficiently achieved with a low impedance is obtainable.

Abstract: A composition for a protective film, which comprises the following components (A), (B), (C) and (D), wherein the proportions of the main components (A) and (B) are substantially from 5 to 60 wt % of (A) and from 35 to 90 wt % of (B), based on the total amount of the composition: (A) a photopolymerizable polyfunctional (meth)acrylate monomer and/or oligomer; (B) an oligomer or polymer of a non-acrylic epoxide; (C) a photopolymerization initiator; and (D) an epoxy-curing agent.