Patent ID: 6840991

Claim:
A method for obtaining an asphalt emulsifier composition comprising the steps of mixing 0.01 to 10% by weight of a kraft lignin (A) having a weight average molecular weight of 4000 to 60000, 0.01 to 10% by weight of at least one polyamine (B) selected from the group consisting of polyamines represented by the formula (1) and polyamines represented by the formula (2): wherein R represents a saturated or unsaturated, straight-chain or branched hydrocarbon having 8 to 22 carbon atoms, m denotes a number from 2 to 10, X denotes a number from 1 to 5 and Y and Z denote a number from 0 to 5, provided that Y and Z are not 0 at the same time, and water; and adding an acid to convert (B) into an amine salt thereof before or after the mixing step, thereby producing said asphalt emulsifier composition.