Abstract: Unique heat transfer fluid media include (methylbenzyl)xylene or a composition comprising admixture of the compounds (A): ##STR1## in which n.sub.1 +n.sub.2 =0 or 1, wherein a fraction of such compounds (A) n.sub.1 +n.sub.2 =0 and further wherein another fraction of such compounds (A) n.sub.1 +n.sub.

Abstract: Unique heat transfer fluid media include (methylbenzyl)xylene or a composition comprising admixture of the compounds (A): ##STR1## in which n.sub.1 +n.sub.2 =0 or 1, wherein a fraction of such compounds (A) n.sub.1 +n.sub.2 =0 and further wherein another fraction of such compounds (A) n.sub.1 +n.sub.

Abstract: Novel heat-sensitive recording media include a support substrate, e.g., paper or a synthetic polymer film, having a thermosensitive recording layer deposited thereon, such thermosensitive recording layer comprising a colorant precursor, a heat-sensitive developer therefor and at least one polyphenylmethane of the formula (A1): ##STR1## in which R.sub.1 and R.sub.2, which may be identical or different, are each a halogen atom, NO.sub.2, CN, OCH.sub.3, H or an alkyl radical having up to 5 carbon atoms; n is 3, 4 or 5; p is 1, 2 or 3; g is 0 or 1 and the maximum value of p+g is 2; and the melting point of which polyphenylmethane being at least 50.degree. C.