abstract |
A process for the preparation of aqueous epoxy resin dispersions comprising (1) 20 to 75% by weight, based on the total dispersion, of an epoxy resin constituting a condensation product of a) epoxy compounds having at least one epoxy group per molecule and an epoxide equivalent weight of 90 to 3000 g/mol, and b) aromatic polyols; (2) 3 to 20% by weight, based on the total dispersion, of an emulsifier comprising a) a condensation product of an aliphatic polyol and an epoxy compound having at least two epoxy groups per molecule and an epoxide equivalent weight of 90 to 3000 g/mol, the equivalent ratio of the OH groups to the epoxy groups being 1:0.85 to 1:1.5 and the epoxide equivalent weight of this condensation product being between 5000 and 400,000 g/mol, b) an organic solvent, and c) water; (3) up to 10% by weight, based on the total dispersion, of organic solvents; and (4) water in an amount to make up to 100% by weight, which comprises stirring the epoxy resin (1) firstly with the emulsifier (2) and, if appropriate, organic solvents corresponding to (3), and then with water. |