| abstract |
1. A polymer which is insoluble in water, but soluble in aqueous alkaline solutions and which contains repeating units of the general formula I see diagramm : EP0212439,P15,F1 in which R is a hydrogen or halogen atom, a cyanide group or an alkyl group of 1-4 carbon atoms, R**1 , R**2 and R**3 are identical or different and denote hydrogen or halogen atoms, alkyl, alkoxy or alkoxy-carbonyl groups, R**4 is a hydrogen atom or a divalent organic group which is intermolecularly or intramolecularly linked to a further unit of the formula I, on average at least one R**4 of each polymer unit corresponding to formula I being hydrogen, A denotes the atoms required for completing a mononuclear or dinuclear carbocyclic or heterocyclic aromatic ring system and m is 2 or 3. |