Patent ID: 6995223

Claim:
An aqueous dispersion of a copolymer of at least one 3,4-alkylenedioxythiophene compound with a solubility in water at 25° C. of less than 2.2 g/L with at least one 3,4-alkylenedioxythiophene compound with a solubility in water at 25° C. of at least 2.2 g/L and a polyanion, wherein said 3,4-alkylenedioxythiophene compound with a solubility in water at 25° C. of at least 2.2 g/L is selected from the group consisting of: 3,4-dihydro-2H-thieno[3,4-b][1,4]dioxin-2-yl)methanol, 3,4-dihydro-2H-thieno[3,4-b][1,4]dioxepin-3-ol, (2,3-dihydro-thieno[3,4-b][1,4]dioxin-2-yl-methoxy)-acetic acid ethyl ester, (2,3-dihydro-thieno[3,4-b][1,4]dioxin-2-yl-methoxy)-acetic acid, 2-{2-[2-(2-methoxy-ethoxy)-ethoxy]-ethoxymethyl}-2,3-dihydro-thieno[3,4-b][1,4]dioxine and 4-(2,3-dihydro-thieno[3,4-b][1,4]dioxin-2-ylmethoxy)-butane-1-sulfonic acid sodium salt.