Method for production of a liquid composition of an ortho-dihydroxybenzyl compound of high purity and said composition

A process for the preparation of a liquid composition of an ortho-dihydroxybenzyl compound of high purity comprising the consecutive steps of:

• a) purifying the initial ortho-dihydroxybenzyl compound by distillation,
• b) condensing the purified ortho-dihydroxybenzyl compound obtained in step a) in an apparatus resistant to corrosion by the latter,
• c) recovering the condensed ortho-dihydroxybenzyl compound obtained in step b) closest to its distillation point,
• d) mixing the recovered ortho-dihydroxybenzyl compound in step c) with an organic solvent in a storage tank which is lined or made of a material which does not lead to metallic pollution, and, then
• e) obtaining the liquid composition of the ortho-dihydroxybenzyl compound having less than 100 ppb metallic elements,
• wherein the distillation step a) and the condensation step b) of the purified ortho-dihydroxybenzyl compound take place in an apparatus made of stainless steel 304, 304 L, 316, or 316 L, and
• wherein the steel has at most 22% by weight of nickel.