Use in a machine dishwashing and rinsing composition of an amphoteric copolymer as soil antiredeposition agent

Use in a two-in-one or three-in-one washing and rinsing composition for the machine cleaning of kitchen- and tableware of a water-soluble or water-dispersible amphoteric copolymer comprising in the form of polymerized units

• (a) at least one monomeric compound of general formula I
• 3
• in which
• R1 and R4 represent independently of one another a hydrogen atom or a linear or branched C1-C6 alkyl group;
• R2 and R3 represent independently of one another an alkyl, hydroxyalkyl or aminoalkyl group in which the alkyl group is a linear or branched C1-C6 chain, preferably a methyl group;
• n and m are integers of between 1 and 3;
• X represents a counterion compatible with the water-soluble or water-dispersible nature of the polymer;
• (b) at least one hydrophilic monomer which carries an acidic function, is copolymerizable with (a) and is capable of undergoing ionization in the application medium,
• (c) where appropriate, at least one ethylenically unsaturated hydrophilic monomeric compound of neutral charge which carries one or more hydrophilic groups and is copolymerizable with (a) and (b),
• wherein the a/b molar ratio is between 15/85 and less than 50/50, preferably between 25/75 and 45/55, as a soil antiredeposition agent.