| 摘要 |
<p>PROBLEM TO BE SOLVED: To obtain a carbon black dispersion that can give an ink having improved storage stability, not plugging the nozzles of an ink recording apparatus, and stably giving a good image by using a first carbon black highly dispersible in water and a second carbon black lowly dispersible in water. SOLUTION: The first carbon black highly dispersible in water is obtained by making hydrophilic the surface of the second carbon black lowly dispersible in water. The treatment for making the surface hydrophilic is exemplified by a treatment comprising bonding hydrophilic groups to the surface of the second carbon black. The hydrophilic group is exemplified by -OL, -N+R1R2R3X-, -COOM, -SO3M, -(CH2CH2O)nR4, -YOL, or -YCOOM (wherein L is H, Na or K; X- is Br or the like; M is H, Na, K or the like; (n) is 1 or greater; Y is an alkylene or the like; and R1 to R4 are each H, an alkyl, an aralkyl or the like).</p> |
