HEAT ACCUMULATING MATERIAL

To provide a heat accumulating material capable of suppressing super-cooling only with one kind of an organic heat accumulating material.SOLUTION: A heat accumulating material contains a viologen compound represented by the following formula (1), The R is preferable to be an aliphatic alkyl group having 3 to 18 carbons. The heat accumulating material preferably has a melting point-freezing temperature difference ΔTm-Tf that is a temperature difference obtained by subtracting a freezing point Tf where an isotropic liquid freezes during cooling from a melting point Tm that is a temperature where the heat accumulating material becomes the isotropic liquid by melting during heating is preferable to be 30°C or smaller. The heat accumulating material is preferable not to contain a supercooling inhibitor. Formula 1 (in the formula (1), R represents an aliphatic alkyl group, and X represents a halogen element or bis(trifluoromethanesulfonyl)imide.)SELECTED DRAWING: Figure 5 【課題】１種類の有機蓄熱材のみで過冷却を抑制可能な蓄熱材を提供する。【解決手段】蓄熱材は、下記式（１）で表されるビオロゲン系化合物を含む。前記Ｒは炭素数３〜１８個の脂肪族アルキル基であることが好ましい。蓄熱材は、加熱時に融解して等方性液体になる温度である融点Ｔｍから、冷却時に等方性液体が凝固する温度である凝固点Ｔｆを差し引いた温度差である融点−凝固点温度差ΔＴｍ−Ｔｆが３０℃以下であることが好ましい。蓄熱材は、過冷却抑制剤を含まないことが好ましい。【化１】（式中、Ｒは脂肪族アルキル基、Ｘはハロゲン元素又はビス（トリフルオロメタンスルホニル）イミド、を表す。）【選択図】図５