Water-soluble reactive polymer mixture

A water-soluble reactive binder, characterised by a combination of at least three of the components

• (a) at least one halogen-free polycarboxylic acid compound;
• (b) at least on salt-forming substance selected from the group consisting of alkali metal, alkaline earth metal and quaternary ammonium salts, organic bases and ammonia;
• (c) at least one component selected from the group consisting of
• (c1) a polymer containing OH groups;
• and
• (c2) an epoxide compound,
• wherein the components (a) to (c2) are present as such or at least partially in chemically bonded form, which binder contains at least one reaction product of one of the formulae ##STR12## based on at least three of the components (a) to (c2), wherein R.sup.1 represents a group derived from at least one component (c1) selected from the group consisting of (.alpha.) a polymer containing OH groups, in the form of (.alpha.1) polyesters, (.alpha.2) polymers, both with an OH number of 20 to 300, (.alpha.3) phenolic resins with an OH number of 100 to 800, and (c2) an epoxide compound;
• R.sup.2 represents a group derived from an at least tetrabasic carboxylic acid with a COOH group in the o-position relative to the ester group;
• R.sup.5 represents a group derived from an at least dibasic carboxylic acid with a COOH group in the o-position relative to the ester group, and R.sup.5 may have the same meaning as R.sup.2 ;
• and the anhydride groups in formulae (I) and (Ia) are present as such or are at least partially replaced by at least one of the groups COOH and ester groups and the COOH groups are present as such or are replaced at least partially by ester groups, and wherein the free COOH groups are present in an amount of from 1 to 100% in the form of a salt of component (b).