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WO 93/15510 discloses also xylenol orange and sulfor› hodamines which all are also sulphonic acids. According to Comparative Example la the sulphodyes of WO 93/15510 (being sulphonic acids) are solvents of sulphonic acid doped PANI (taken that the particular sulfodyes melt at all). 

Note that all sulphonic acids are strong acids with typi› cally pKa<l. thus being strongly corrosive. Henceforth their technological value is questionable. Therefore in this patent application the inventors searched for substantially less acidic solvents. 

It is known from previous art that solubility of high polymers to solvents is augmented by strong specific inter› actions between the solvent and polymer molecules. If one exposes emeraldine base to sulphonic acid, one of the expected specific interactions is protonation of the iminic nitrogens. The essential protonation is known in the previous art to take place only if the acid is sufficiently acidic with pKa less than about 3. Therefore in the following the inventors search for novel solvents which are not able to protonate i.e. are less acidic i.e. pKa is greater than about 3. 

According to the teachings of WO 92/22911. DBSA and CSA were selected to be the protonating acids to prepare PANl(DBSA)o.s and PANI(CSA)$_{0 }$$_{5}$. Outside WO 92/22911. MSA was selected as the most simple sulphonic acid dopant to form PANl(MSA)$_{0}$ _ 5 . The protonations were performed according to Method A2. Further more, typical solvents of WO 92/22911 were selected: 3-methoxy phenol. 2-methyl- 4-methyl phenol, m-cresol and p-cresol. The solubility of 10 parts by weight of PANl(DBSA)$_{0}$ _ 5 • PANI(CSA)$_{05 }$ and PANI(MSA)$_{0}$ _ 5 to 90 parts by weight of 3-methoxy phenol. 2-methyl-4-methyl phenol. m-cresol and p-cresol was stud› ied according to Method B using mixing temperature of 200°-210° C. 

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One concludes that the high solubility to 3-methoxy phenol. 2-methyl-4-methyl phenol. m-cresol and p-cresol. as taught by WO 92/22911, is limited to PANI protonated by selected i.e. specific sulphonic acid counter ions, such as CSA. 

In particular WO 92/22911 does not teach how to render PANI doped by any sulphonic acid (such as the simplest sulphonic acid MSA) or in general organic acid highly soluble. 

PANI(DBSA)o_$_{5}$• PANI(CSA)$_{0}$ _$_{5 }$and PANl(MSA)$_{0}$ _ $_{5 }$were prepared using Method A-2. The solubility of 10 parts by weight of PANI(DBSA)$_{0}$ _ 5 • PANI(CSA)o_ $_{5}$and PANI(MSA) 0 _ $_{5 }$to 90 parts by weight of hydroquinone (HQ) or Methyl hydroquinone MeHQ was studied according to Method B using mixing temperature of 200°-210° C. 

## Comparative Example Illa (Outside of the Invention) 

## Comparative Example la 

