| 摘要 |
PROBLEM TO BE SOLVED: To provide ink composition without deteriorating plastic material in an ink jet recorder using the material. SOLUTION: It is discovered that one of causes of deteriorating plastic material in an ink jet recorder is free ammonia concentration in the ink composition. Accordingly, in the recorder in which the composition is brought into contact with the plastic in an ink supply system and/or ink jet recording head, the composition having 2000 ppm or less of the free ammonia concentration is used. |
