Case T-176/19: Judgment of the General Court of 16 December 2020 — 3V Sigma v ECHA (REACH — Substance evaluation — UVASORB HEB — Decision of the ECHA requesting further information — Article 46(1) of Regulation (EC) No 1907/2006 — Request seeking to identify potential transformation or degradation products of the substance — Proportionality — Need for the additional study requested — Relevant conditions and realistic conditions — Study temperature — Manifest error of assessment)