Such cells may be used over a wide temperature range, and have good capacity.

Wide temperature range where the liquid temperature and the ambient temperature are independent of each other.

The process for producing the coloring compositions employs a lower temperature range than the prior art; this reduces the need for equipment heating and enables the equipment to be more readily cleaned.

A fluorinated aromatic compound represented by formula (I), utilizable for preparing a magnetic fluid having a wide heat-resistant temperature range and a high water resistance.

The inventive heat-storing medium for a very low temperature range consists of a set (22) of pourable, gas tight, closed, hollow bodies (30).