| 摘要 |
PROBLEM TO BE SOLVED: To provide a binder for a magnetic recording medium, excellent in dispersibility of magnetic powder and enabling magnetic properties of the magnetic recording medium to be improved.SOLUTION: There is provided a resin (P) binder consisting of polyol (A) containing diol (a1) having a sulfonic acid (sulphate) group represented by the general formula (1) and a polyisocyanate component (B), where Ris a C2 to C12 bivalent hydrocarbon, Ris H, a methyl group or a group represented by -R-O-R-SOM, Ris H, a methyl group, an ethyl group or a group represented by -R-O-R-SOM, Ris a direct bond or a methyl group, Ris a direct bond, a methylene group, an ethylene group or a propylene group, Ris a propylene group or a 2-methyl-1,3-propylene group, L is C or a specific tetrafunctional group, Mis a specific action and m and n are integers of 1 to 10. |
