Phase A: Dissolve L-Ascorbic Acid in distilled water via agitation and gentle heating (warm, never hot or you will denature the ascorbic acid). Eng. 0000002585 00000 n In another embodiment of the invention, hydroquinone and a protected retinoid are both combined in the composition. Availability. 0000085850 00000 n Formula of hydroquinone is . It is highly soluble in water (70 g/litre at 25 C) and the log n-octanol/water partition coefficient is 0.59. Hope it helps 6 yrs later. Forms of retinoids have been developed wherein the retinoid is protected by a protective system. Other properties of hydroquinone are given in Table 1. 0000002544 00000 n Google Scholar, W. J. Weber Jr, Y.-P. Chin, C. P. Rice, Water Res. Also in this embodiment is a cationic salt of acidic ascorbyl esters, which further helps to maintain the acceptable color desired in the hydroquinone composition. Correspondence to EP2047846A2 - Process for stabilizing hydroquinone - Google Anyone you share the following link with will be able to read this content: Sorry, a shareable link is not currently available for this article. Chemically, hydroquinone is designated as p-dihydroxybenzene; the empirical formula is C 6 H 6 O 2; molecular weight is 110.0. Hydroquinone can be made through several routes. Since hydroquinone has a tendency to discolor through oxidation, these antioxidants are used because they have greater tendencies to oxidize than hydroquinone. [21][25][23] NTP evaluation showed some evidence of long-term carcinogenic and genotoxic effects[26], While hydroquinone remains widely prescribed for treatment of hyperpigmentation, questions raised about its safety profile by regulatory agencies in the EU, Japan, and USA encourage the search for other agents with comparable efficacy. Crit. Calorim. Remove contact lenses, if present and easy to do. INCI HydroquinoneEastman Hydroquinone, USP is a skin care ingredient used to produce effective skin- lightening applications for depigmentation. HMkA+"c>jZ^ho=81NW;]Ib;+i#iFArHpz). `9F6~qg3]0,#!V9Q> p=|h| 420, 2429 (2016), W. E. Acree Jr, Thermochim Acta 189, 3756 (1991), F. L. Nordstrm, . C. Rasmuson, J. Chem.