PROBLEM TO BE SOLVED: To provide a technique of producing an iridoid compound-derived red dye composition having light resistance, being a technique suitable in the points of safety and production cost.SOLUTION: Provided is a method for producing an iridoid compound-derived red dye composition comprising a process where red coloring going with an action between iridoid aglycon having a carboxyl group at the fourth place of an iridoid skeleton and an amino group-containing compound is performed with a solution containing dicarboxylic acid having a specified structure of succinic acid, malic acid or the like to the total mol equivalence of the iridoid compound, a compound similar to the same and two or more compounds selected therefrom by a 5 mol equivalence or more to produce a red dye compound having light resistance.SELECTED DRAWING: Figure 9COPYRIGHT: (C)2018,JPO&INPIT【課題】安全性及び製造コストの点で好適な技術であり、耐光性を備えたイリドイド化合物由来赤色素組成物を製造する技術の提供。【解決手段】イリドイド骨格の4位にカルボキシル基を有するイリドイドアグリコンとアミノ基含有化合物との作用を伴う赤色発色を、イリドイド化合物の総モル当量に対してコハク酸又はリンゴ酸等の特定構造を有するジカルボン酸、その類似化合物、又はこれらから選ばれる2以上の化合物、を5モル当量以上含有する溶液にて行って、耐光性を備えた赤色素化合物を生成する工程、を含む、イリドイド化合物由来赤色素組成物の製造方法。【選択図】図9
