Diphyl DT is a mixture of isomeric ditolyl ethers (dimethyl diphenyloxides). It boils in the temperature range between 284 and 294 ° C at 1.013 bar. It can be operated under pressure, in liquid phase up to 330 ° C.
Special mention should be made of the low viscosity of Diphyl DT even at low temperatures. With a pour point of -54 ° C, Diphyl DT can be operated even at temperatures as low as -30 ° C.

Its autoignition temperature is 545 ° C, meaning Diphyl DT is classified as T1 temperature class. Unlike water, the conversion from a liquid to a solid state reduces the volume. Device and pipelines are not damaged as a result of solidification of Diphyl DT filling. The typical natural scent of Diphyl DT allows leaks to be identified quickly. The level of production-related impurities such as chlorine and sulfur compounds is so low that the likelihood of corrosive damage caused by HTF is low.