PROBLEM TO BE SOLVED: To provide an ink for ink jet which can maintain preferable quality without causing failure such as discharge defect in printing, even when using a black iron oxide which has heavy specific gravity and cannot be easily held in an ink in a uniform and stable manner and which easily causes pigment sedimentation.SOLUTION: There is provided an ink for ink jet which contains at least a black iron oxide, carboxymethyl cellulose neutralization salt whose weight average molecular weight is 20000 or smaller and an acid substance, and the ink for ink jet comprises a pH value of 7.0 to 12.0.SELECTED DRAWING: NoneCOPYRIGHT: (C)2020,JPO&INPIT【課題】 比重が重くインク中に均一に安定し保持させることが難しく顔料沈降を起こし易い黒酸化鉄を用いても、印字の際に吐出不良等のの不具合を起こすこともなく良好な品質を保つインクジェット用インクを提供する。【解決手段】 少なくとも黒酸化鉄、重量平均分子量が２００００以下のカルボキシメチルセルロース中和塩及び酸物質を含有し、ｐH値が７．０～１２．０であることを特徴とするインクジェット用インク。【選択図】なし
