DYE DISPERSANT

To provide a lignin-based dye dispersant having excellent storage stability of a disperse dye.SOLUTION: A disperse dye composition using a dye dispersant containing a sulfomethylated lignin produced by reacting lignin such as kraft lignin with a sulfite and aldehydes was prepared and the storage stability was compared. There is provided a dye dispersant containing a sulfomethylated lignin, wherein a dye dispersant in which the organic S content contained in the sulfomethylated lignin is 1.0 mass% or more and 6.0 masa% or less had excellent storage stability with almost no change in viscosity even after standing for 7 days, compared to the condition in which the dye dispersant was prepared from N material kraft lignin.SELECTED DRAWING: None 【課題】分散染料の貯蔵安定性に優れるリグニン系染料分散剤を提供する。【解決手段】クラフトリグニン等のリグニンに亜流酸塩、及びアルデヒド類を反応させて製造したスルホメチル化リグニンを含有する染料分散剤を用いた分散染料組成物を調製し、貯蔵安定性について比較した。スルホメチル化リグニンを含有する染料分散剤であって、前記スルホメチル化リグニンに含まれる有機態Ｓ含量が１．０質量％以上６．０質量％以下である染料分散剤は、Ｎ材クラフトリグニンを染料分散剤にした条件と比較して、7日間静置してもほとんど粘性が変化することなく、貯蔵安定性に優れていた。【選択図】なし