Phase B: Dissolve the ferulic acid in the glycerin - some "spirited" stirring may be necessary. I'm using it for spot treatment of some hyper pigmentation (less than 1% of my body). Privacy Policy. Antioxidants in the hydroquinone phase are instrumental in stabilizing the color of the hydroquinone composition. 0000000807 00000 n LSPS, Laboratoire de Spectrochimie Et Pharmacologie Structurale, University of Tlemcen, BP 119, 13000, Tlemcen, Algeria, Department of Biology, University of Ghardaia, BP 455, 47000, Ghardaia, Algeria, You can also search for this author in Chem. 0000008514 00000 n This page was last modified on 19 June 2019, at 20:05. When the contents of the reservoir are forced into the reaction chamber, the catalases and peroxidases rapidly break down the hydrogen peroxide and catalyze the oxidation of the hydroquinones into p-quinones. 109. New experimental data are provided for the solubility of resorcinol in water and salicylic acid, resorcinol, hydroquinone in 1-octanol. Other properties of hydroquinone are given in Table 1. Hydroquinone (EHC 157, 1994) - International Programme on Chemical Safety The solubility in water is 6.72g/L. Cookie Notice I can only tell you how to mix the powder solution to the liquid solvent. Data 53, 12781282 (2008), A. Correspondence to antiphlogistics and cardiaca, Cosmetics or similar toilet preparations characterised by the composition, Cosmetics or similar toilet preparations characterised by the composition containing inorganic ingredients, Sulfur; Selenium; Tellurium; Compounds thereof, Cosmetics or similar toilet preparations characterised by the composition containing organic compounds, Cosmetics or similar toilet preparations characterised by the composition containing organic compounds containing oxygen, . Retinoids are included in the invention from about 0.01 to about 5%, preferably from about 0.025% to about 2.0%, more preferably from about 0.05% to about 1%, and most preferably from about 0.025% to about 0.5%. . For use herein, the encapsulation forms a protective system to prohibit or inhibit the oxidation of the retinoid. Pigmentation disorders can take a variety of forms like hyperpigmentation and hypopigmentation, such as melasma (dark patches experienced in pregnancy), liver spots (which often develop with age), as a side effect of birth control pills, and as a persistent result of acne, bums, bites and other skin injuries, and vitiligo. 108. Solubilities of hydroquinone and p-quinone in - ScienceDirect Then take the water and put the measurement into the microwave until boiled. Polysorbate 20 0.5% 0.15g. Chem. Johnson & Johnson Consumer Products, Inc. Johnson & Johnson Consumer Companies, Inc. AT BE CH CY DE DK ES FI FR GB GR IE IT LI LU MC NL PT SE TR, STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN, Color Stability of 4% HQ Compositions with varying pH and % Sodium Metabisulfite at 5C and 40C, Color Stability of 4% HQ Compositions with varying pH and % Magnesium Ascorbyl Phosphate at 5C and 40C, Polyacrylamide (and) C 13-14 isoparaffin (and) laureth-7, Water, Soybean (Glycine Soja) Oil, Carnauba (Copemicia Cerifera), wax, tocopherol, retinol, Ceteareth-20, Water, Soybean (Glycine Soja) Oil, Carnauba (Copernicia Cerifera), wax, tocopherol, retinol, Ceteareth-20, Compositions for the treatment of pigmentation disorders and methods for their manufacture, Stabilization composition including hydroquinone or derivative thereof, Stabilized retinol for cosmetic dermatological, and pharmaceutical compositions, and use thereof, Depigmenting composition for the skin comprising adapalene and at least one depigmenting agent, Depigmenting composition for the skin, use of a depigmenting composition for the skin, cosmetic use of the same and method for non-therapeutic cosmetic treatment, Cosmetic designs and products using intronic RNA, Holistic composition and method for reducing skin pigmentation, Topical compositions and methods of manufacturing them in specifically treated steel vessels, System for improved percutaneous absorption of skin benefiting agents, Discontinuous surface coating for particles, Method of treating skin requiring chemical peel procedure, Method of treating skin needing hyaluronic acid treatment, Method of treating skin having incision from surgical procedures, Method of treating skin requiring hair removal procedure, Method of treating skin requiring Intense Pulse Light (IPL) procedure, Method of treating skin subject to or affected by aesthetic surgical procedures, Method of treating skin needing ablative treatment, Method of treating skin requiring radiofrequency procedure, Method of treating skin requiring non-ablative procedure, Method of treating skin requiring fractional resurfacing treatment, Method of treating skin needing botulinum toxin type a treatment, Method of treating skin requiring microdermabrasion, Method of treating skin needing collagen treatment, Method of treating skin requiring skin cancer treatment, Methods of treating skin to enhance therapeutic treatment thereof, Ras mutation and compositions and methods related thereto, Compositions, kits and regimens for the treatment of skin, especially dcolletage, Calcium sequestration compositions and methods of treating skin pigmentation disorders and conditions. Inhalation Remove to fresh air. Glycerol derivatives solubilise natural, hydrophilic antioxidants in biofuels. 76/768/EEC:1976 Council Directive 76/768/EEC of 27 July 1976 on the approximation of the laws of the Member States relating to cosmetic products: Organic Chemistry, Solomon and Fryhle, 10th edition, Wiley Publishing, 2010. 0000002585 00000 n Using a laser-monitoring observation technique, the solubility of hydroquinone in water, methanol, ethanol, 2-propanol, ethyl acetate, butyl acetate, and acetic acid were measured at temperatures ranging from 276.65 K to 345.10 K under the atmospheric pressure. Your document download will begin shortly. Substituted derivatives of this parent compound are also referred to as hydroquinones. It is moderately soluble in water and highly soluble in alcohol. Using a laser-monitoring observation technique, the solubility of hydroquinone in water, methanol, ethanol, 2-propanol, ethyl acetate, butyl acetate, and acetic acid were measured at temperatures ranging from 276.65 K to 345.10 K under the atmospheric pressure. In 1-octanol, the decreasing order of the solubility of these compounds is as follows: resorcinol>benzoic acid>salicylic acid>hydroquinone. This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions. The correlation coefficient is greater than 0.9937 for one of these two equations for the binary studied systems where the solvent is either water or 1-octanol. It can also be found on eBay and Amazon. I can't use water because I cannot dissolve enough Hydroquinone into it to reach the desired concentration. With an account you can check out faster, view your online order history and access your shopping bag or saved items from any device. stearic, palmitic, arachidic acids, Heterocyclic compounds having oxygen as the only ring hetero atom, e.g. Other adverse effects Additionally, the hydroquinone compositions frequently discolor over time and turn from a whitish color to a brown or even black. Hydroquinone Revision Date 24-Dec-2021 General Advice If symptoms persist, call a physician. Best Budget Hydroquinone Cream Ambi Skincare Fade Cream (56g/2oz) View on Amazon. HYDROQUINONE (hahy droh kwi NOHN) is applied to the the skin to lighten areas that have darkened. - 65.21.225.73. 4]DYR@'c This website uses cookies. InChI=1S/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H, InChI=1/C6H6O2/c7-5-1-2-6(8)4-3-5/h1-4,7-8H, Except where otherwise noted, data are given for materials in their. In the United States, the most commonly used treatment for hyperpigmentation is 1,4-benzenediol, which is known as hydroquinone. In hydroquinone and sodium metabisulfite compositions, it is believed that the sodium metabisulfite oxidizes first and delays the start of any oxidation of the hydroquinone, so that excessive discoloration is delayed or totally avoided. and our Editor's Rating: These can be burning, redness, sensitization and irritation in some patients. It is soluble in water. Hydroquinone is considered to be readily biodegrable and photodegradable. It is also used to prepare 2% bleaching creams and certain intermediates for the synthesis of dyes, and it has some activity as an antitumoragent. 0000005306 00000 n It is highly soluble in water (70 g/litre at 25 C) and the log n-octanol/water partition coefficient is 0.59. 2 Liquid phase only; silicon dioxide remains as a residue in these solvents. 38, 565571 (2006), K. Carlsson, B. Karlberg, Anal. I did that by using 1 cup of cream, 4tbsp of hydroquinone and 4tbsp of water or solvent. On this Wikipedia the language links are at the top of the page across from the article title. SOLUBILITIES - DrugFuture 0000004197 00000 n We have found that a cream containing 5% of hydroquinone and 0.05 % of laevo-ascorbic acid remains white, and the emulsion remains unbroken after many months of storage, The laevo-ascorbic or cevitamic acid is pr'eferably employed in the free condition; but if desired, the salts, and especially the water-soluble salts thereof, may be employed . Determination and Correlation of Solubilities of Benzoic Acid, Salicylic Acid, Resorcinol and Hydroquinone in Water and in 1-Octanol at Temperatures from 297.25K to 334.45K. If you are already a ChemPoint customer then sign up for access to our online ordering website. It has a white-solid appearance. [Na+].OC(=O)CC(O)(CC([O-])=O)C(O)=O.OC(=O)CC(O)(CC([O-])=O)C(O)=O, SPECIFIC USE OF COSMETICS OR SIMILAR TOILET PREPARATIONS, Preparations for care of the skin for chemically bleaching or whitening the skin, PREPARATIONS FOR MEDICAL, DENTAL, OR TOILET PURPOSES, Medicinal preparations containing organic active ingredients, Acids; Anhydrides, halides or salts thereof, e.g. They may also include ingredients with other therapeutic actions, such as anti-inflammatories, antibiotics, exfoliants and peels. trailer << /Size 393 /Info 347 0 R /Root 375 0 R /Prev 573815 /ID[<6893db2526a970a0c364cca2e99ca522>] >> startxref 0 %%EOF 375 0 obj << /Type /Catalog /Pages 346 0 R /Metadata 348 0 R >> endobj 391 0 obj << /S 2217 /Filter /FlateDecode /Length 392 0 R >> stream It exerts a depigmenting effect on skin of mammals by increasing the excretion of melanin from the melanocytes. 0000000731 00000 n PDF HYDROQUINONE HEALTH AND SAFETY GUIDE - World Health Organization HYPERPIGMENTARY STAIN ELIMINATING CREAM FOR FACE SKIN AND ITS USE. The combined nearly ideal binary solvent (NIBS)-Redlich-Kister equation is . The most preferred example of such an antioxidant is sodium metabisulfite. vitamin C; Salts thereof, Medicinal preparations containing active ingredients not provided for in groups A61K31/00-A61K41/00, Mixtures of active ingredients without chemical characterisation, e.g. ChemPoint will not under any circumstances release personal user information to individuals or companies. fungichromin having five-membered rings with one oxygen as the only ring hetero atom, e.g. Read our Privacy Notice. AzA inhibits tyrosinase. All Rights Reserved, View All Eastman Hydroquinone USP Articles. Anal. This range of pH has been preferred for hydroquinone compositions, because it has been believed that the hydroquinone is less likely to excessively discolor under acid conditions. [Na+].OC(=O)CN(CC([O-])=O)CCN(CC(O)=O)CC([O-])=O, trimethyl-[phenyl-bis(trimethylsilyloxy)silyl]oxysilane, C[Si](C)(C)O[Si](O[Si](C)(C)C)(O[Si](C)(C)C)C1=CC=CC=C1, C\C(=C/C=O)\C=C\C=C(\C=C\C1=C(CCCC1(C)C)C)/C, 1-hexadecanoyl-2-(9Z,12Z-octadecadienoyl)-sn-glycero-3-phosphocholine, CCCCCCCCCCCCCCCC(=O)OC[C@H](COP([O-])(=O)OCC[N+](C)(C)C)OC(=O)CCCCCCC\C=C/C\C=C/CCCCC, 2-[2-[2-[2-[2-[2-(2-dodecoxyethoxy)ethoxy]ethoxy]ethoxy]ethoxy]ethoxy]ethanol, C[Si]1(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O[Si](C)(C)O1, O=C1C(=O)C(C2=CNC3=C(C(C(=O)C4=C32)=O)C)=C2C4=CNC2=C1C, [Na+].[Na+].[Na+]. 2005 Wiley-VCH, Weinheim. https://doi.org/10.1007/s10765-020-02750-4. COMMON BRAND NAME (S): Aclaro, Aclaro PD, Alera, Alphaquin HP, Alustra, Claripel, Complex B . The aquatic toxicity of hydroquinone to fresh water fish, Daphnia, and algae was between 0.050- . GHS H Statement: Causes serious eye damage.Suspected of causing genetic defects.May cause an allergic skin reaction.Suspected of causing cancer.Harmful if swallowed.Very toxic to aquatic life. Retinoids, in particular retinoic acid, retinal, and their derivatives, isomers and analogs (such as adapalene, tazarotene and isotretoin), are beneficial for improving rough skin texture, mottled pigmentation, sallow complexion, lines and wrinkles. Monobenzone: Uses, Interactions, Mechanism of Action - DrugBank The document was not able to download due to an unknown error. Conversion factors (at 25 oc and normal atmospheric pressure) 1 ppm = 4.5 mg!m 3 The preferred protected retinoid is in the form of small beads or vesicles which are of a form that can be adjusted to be incorporated into varied topical compositions. ~lgM~Gc{1S_1Q/_/v">S 9 If youre making your lotion. How do I dissolve hydroquinone powder to make a 20% and 10% concentration? Can be destroyed by oxidizing it with an oxidizing mixture. 0000003660 00000 n Google Scholar, A.-C. Huang, Y.-K. Chuang, C.-F. Huang, C.-M. Shu, J. Therm. 0.5% magnesium ascorbyl phosphate protected at pH 6.0-7.0, 1.0-1.5% at pH 5.5-7.0, and 2.0-3.0% at pH 3.5-7.0. Human exposure to hydroquinone can occur by dietary, occupational, and environmental sources. 0000005757 00000 n Toxicol. Found. Our team has been notified and we will fix it as soon as possible. [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. 250, 165172 (2006), F. L. Mota, A. J. Queimada, A. E. Andreatta, S. P. Pinho, E. A. Macedo, Fluid Phase Equilib. M1 and M2 microemulsions contain ethanol as co-surfactant. There are various other uses associated with its reducing power. 115, 22772285 (2014), Article Hydroquinone is used as a topical application in skin whitening to reduce the color of skin. Protected retinoid may be added to these compositions for additional skin benefit effects. The disodium diphenolate salt of hydroquinone is used as an alternating comonomer unit in the production of the polymer PEEK. Hydroquinone is combustible when preheated. Eng. It is found in wheat, rye, and barley.It is a precursor to diverse industrial products including polymers and plasticizers, as well as being a component of a number of hair and skin conditioners. Hydroquinone USP, Eastman - ChemPoint 65, 5786 (1998), Y.-H. Zhang, Trends Analyt. Hydroquinone (HSG 101, 1996) - International Programme on Chemical Safety As a polymerisation inhibitor, exploiting its antioxidant properties, hydroquinone prevents polymerization of acrylic acid, methyl methacrylate, cyanoacrylate, and other monomers that are susceptible to radical-initiated polymerization. sulfur acids, imidic, hydrazonic, hydroximic acids, Carboxylic acids, e.g. Sodium metabisulfite has the added advantage that it does not discolor by oxidation. Since the neutral pH of the hydroquinone composition with sodium metabisulfite and magnesium ascorbyl phosphate is preferably from about 5.5 to about 8.0, more preferably a pH of from about 5.5 to about 7.5, and most preferably at a pH of from about 6.0 to about 7.5, the pH is acceptable for also including retinoids in the composition. Although about 0.01% sodium metabisulfite without magnesium ascorbyl phosphate may not color stabilize an about 4% hydroquinone composition, and about 0.5% magnesium ascorbyl phosphate without sodium metabisulfite may not either, the combination of sodium metabisulfite and magnesium ascorbyl phosphate in these percentages is effective to stabilize the color of the about 1% to about 12%, about 2% to about 10%, preferably about 2% to about 8% and more preferably about 3% to about 4% and most preferably 4% hydroquinone composition. This chamber is lined with cells that secrete catalases and peroxidases. 15, 188196 (1996), U. Domaska, Fluid Phase Equilib. Examples of suitable methods of encapsulation include encapsulation by liposomes, wax, paraffin or any material or combination of materials which protect the retinoid from exposure to oxygen and inhibit oxidation of the retinoid from oxidation. Other aspects, advantages, and modifications are evident from a review of the following claims. Solubility of Hydroquinone in Different Solvents from 276.65 K to 345. This is a prescription-only ingredient in some countries, including the member states of the European Union under Directives 76/768/EEC:1976. We will respond to you shortly. Consistent with a condensation reaction, water was determined to be the primary byproduct. One of these, 4-butylresorcinol, has been proven to be more effective at treating melanin-related skin disorders by a wide margin, as well as safe enough to be made available over the counter. Environ. The Campaign for Safe Cosmetics has also highlighted concerns. Do not put this product in the microwave. How to dissolve Hydroquinone to make 4 oz. [32], Hydroquinone is thought to be the active toxin in Agaricus hondensis mushrooms. For more information, please see our By accepting all cookies, you agree to our use of cookies to deliver and maintain our services and site, improve the quality of Reddit, personalize Reddit content and advertising, and measure the effectiveness of advertising. Get medical attention. Google Scholar, W. J. Weber Jr, Y.-P. Chin, C. P. Rice, Water Res. RJPT - Hydroquinone Solubility in Pure and Binary Solvent Mixture at However, hydroquinone discolors at the pH range of 7.0 to 8.5. This invention addresses the problem of formulating a pigmentation disorder treatment composition with hydroquinone without an excessive discoloration of the composition in the pH range of about 7.0. Other antioxidants, for example cationic salts of acidic ascorbyl esters, most preferably magnesium ascorbyl phosphate, aminopropyl ascorbyl phosphate, and sodium ascorbyl phosphate, have not been utilized in combination with hydroquinone in view of the acidic pH, generally from about 3.4 to about 3.5, and the recommended pH range for magnesium ascorbyl phosphate is about 7.0 to 8.5. According to the polar paradox theory, this should lead to a dissolution of . Hydroquinone is a white, odorless, crystalline solid with an extremely low vapor pressure. Cite this article. The solubilities in binary and ternary systems of hydroquinone (1,4-dihydroxybenzene) and p-quinone (1,4-benzoquinone) in supercritical carbon dioxide were measured in the pressure range 10.0 to 35.0 MPa at temperatures of 333, 348 and 363 K.In binary systems, the solubility of hydroquinone was three orders of magnitude lower than that of p-quinone. &"oq YcbX.=a*t R@ Crit. Res. Thermodyn. Hydroquinone is 1,4-benzenediol. Eng. All information collection is solely used to support ChemPoint customers service communications. Water Solubility 73000 mg/L at 25C 2.6B pH pKa 4.0 - 4.7 pK1 = 9.9 2.12 Oxidation:Reduction Potential +286 mV at 25C and pH 7 ENVIRONMENTAL FATE/BIODEGRADATION Continue rinsing.IF SWALLOWED: Call a POISON CENTER or doctor/physician if you feel unwell.Avoid release to the environment.WARNING: The information provided on this web site was developed in compliance with European Union (EU) regulations and is correct to the best of our knowledge, information and belief at the date of its publication. Belhachemi, B., Makhlouf, H. & Belhachemi, M.H. Hydroquinone IS a white crystalline substance when pure and is highly soluble in water. While patients suffer from pigmentation disorders, they may also suffer from other skin disorders and signs of aging, including but not limited to rough skin texture, mottled pigmentation, sallow complexion, lines and wrinkles. However, a problem with a formulation containing both retinoids and hydroquinone has been their incompatible pH ranges. https://doi.org/10.1007/s10765-020-02750-4, DOI: https://doi.org/10.1007/s10765-020-02750-4. Preparation, optimization and in vivo. The information given is designed only as a guide for safe handling and use. Ferulic acid 0.5% 0.15g. Obagi Nu-Derm Clear (Hydroquinone USP, 4%) Skin Bleaching Cream Obagi application/pdf Treatment with hydroquinone interferes with the action of tyrosinase, which is an enzyme used in the synthesis of melanin, and compositions are sold across the counter at about 2% hydroquinone and by prescription at higher concentrations. 322, 4855 (2012), K. Tamura, T. Kasuga, T. Nakagawa, Fluid Phase Equilib. Retinoids are included from about 0.01% to about 5%, preferably from about 0.025% to about 2%, more preferably 0.05% to about 1.0%, and most preferably from about 0.025% to about 0.5%. Preferably, the protected retinoid, in particular retinoic acid, retinal, and their derivatives, isomers and analogs (such as adapalene, tazarotene and isotretoin), is in the form of small beads or spheres suitable for incorporation into a topical composition. Hydrogen peroxide is used and the reaction gives a mixture of hydroquinone and catechol: An accessible route involves the reaction of sodium hydroxide with 1,4-dichlorobenzene. An acceptable carrier also possesses suitable aesthetic and cosmetic qualities and may include emollients, conditioners and the like. x- [ 0}y)7ta>jT7@t`q2&6ZL?_yxg)zLU*uSkSeO4?c. R -25 S>Vd`rn~Y&+`;A4 A9 =-tl`;~p Gp| [`L` "AYA+Cb(R, *T2B- Hydroquinone is extensively used as a photographic developer, an antioxidant, and a stabilizing agent for readily oxidizable polymers. Stir until uniform. Protected retinoid, with its skin benefit capabilities, may also be included with the hydroquinone composition. [17], An important reaction is the conversion of hydroquinone to the mono- and diamine derivatives. The obtained results show that the solubility of benzoic acid in water is greater than that of salicylic acid, but in the case of the two isomers of dihydroxybenzene, the solubility of resorcinol is approximately 100 times that of hydroquinone. Van Haelst, P. Heesen, F. Van Der Wielen, H. Govers, Chemosphere 29, 16511660 (1994), Article The FDA had classified hydroquinone in 1982 as a safe product - generally recognized as safe and effective (GRASE), however additional studies under the National Toxicology Program (NTP) were suggested in order to determine whether there is a risk to humans from the use of hydroquinone. %PDF-1.4 % Eastman has active ingredients, thickeners, plasticizers, film formers, and more for your personal care formulations. This composition is color stabilized and cosmetically elegant. This study was funded by Ministre de l'Enseignement Suprieur et de la Recherche Scientifique. The present invention addresses the problem of excessive discoloration in hydroquinone compositions of a neutral pH. PDF Hydroquinone Have an order or account question, find answers in our Online Support articles. 330, 4851 (2012), A. Shalmashi, A. Eliassi, J. Chem. Dietland Muller-Schwarze, 2003, page 43 (, National Institute for Occupational Safety and Health, Additive manufacturing of ceramics from preceramic polymers, http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=CELEX:31976L0768:EN:HTML, "Clear N Smooth Skin Toning Cream recalled", Skin Bleaching Drug Products for Over-the-Counter Product Use; Proposed Rule, "About the Center for Drug Evaluation and Research - Hydroquinone Studies Under The National Toxicology Program (NTP)", Campaign For Safe Cosmetics - Hydroquinone, "Skin lightening preparations and the hydroquinone controversy", https://en.wikipedia.org/w/index.php?title=Hydroquinone&oldid=1136453324, Wikipedia articles needing page number citations from October 2016, Pages using collapsible list with both background and text-align in titlestyle, Articles containing unverified chemical infoboxes, Creative Commons Attribution-ShareAlike License 3.0, The most widely used route is similar to the, A potentially significant synthesis of hydroquinone from, Hydroquinone was first obtained in 1820 by the French chemists, Pelletier and Caventou (1820) "Recherches chimiques sur les quinquinas" (Chemical investigations of quinquinas [i.e., the bark of various, This page was last edited on 30 January 2023, at 11:09. Hydroquinone[1] Idrochinone Quinol 1,4-Dihydroxybenzene p-dihydroxybenzene p-hydroxyphenol 1,4-Hydroxy benzene Identifiers CAS Number 123-31-9 Y 3D model (JSmol) Interactive image Beilstein Reference 605970 ChEBI CHEBI:17594 Y ChEMBL ChEMBL537 Y ChemSpider 764 Y DrugBank DB09526 ECHA InfoCard 100.004.199 EC Number 204-617-8 Gmelin Reference 2742 374 0 obj << /Linearized 1 /O 376 /H [ 807 1414 ] /L 581425 /E 96582 /N 109 /T 573826 >> endobj xref 374 19 0000000016 00000 n Hydroquinone is combustible when preheated. 43, 13111316 (2007), J. Qing-Zhu, M. Pei-Sheng, Z. Huan, X. Shu-Qian, W. Qiang, Q. Yan, Fluid Phase Equilib. Thermodyn. Determination and Correlation of Solubilities of Benzoic Acid The solubilities of benzoic acid, salicylic acid, resorcinol and hydroquinone in water and in 1-octanol were measured by the dynamic method which is also called the synthetic method from 297.25K to 334.45K. Using differential scanning calorimetry (DSC Q2000 and SDT Q600), the melting temperature and the enthalpy of fusion of these solutes were determined. uv curable cellulose estersuv curable cellulose esters . . Glycerol and citric acid, non-toxic and renewable reagents, were crosslinked by a melt polymerization reaction at temperatures from 90-150C. Table II shows that at 5C, 4% hydroquinone compositions maintain their white or light straw color with the addition of at least about 0.5% magnesium ascorbyl phosphate at the low pH ranges (from about 3.50 to about 5.50) and when about 1.0 to about 2.0% magnesium ascorbyl phosphate is used in the pH range of about 7.0. So, does anybody know of another solvent I could use that has a higher solubility and is relatively non-toxic. [22] The FDA stated that hydroquinone cannot be ruled out as a potential carcinogen. 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. How to make CE Ferulic with HA and NO propylene glycol? A2, Designated state(s): The protective system can be an entrapment system, a single or multi- laminar system, such as by the formation of vesicles such as a liposome or by utilizing wax, paraffin, silicone, polyethylene, or any material or system which protects the retinoid from oxidation. The toxicology of hydroquinone - relevance to occupational and environmental exposure. It is a major component in most black and white photographic developers for film and paper where, with the compound metol, it reduces silver halides to elemental silver. Hydroquinone can lose a hydrogen cation from both hydroxyl groups to form a diphenolate ion. Thus, while cationic salts of acidic ascorbyl esters, preferably magnesium ascorbyl phosphate and aminopropyl ascorbyl phosphate, have beneficial antioxidant effects on the skin, the combination with hydroquinone in the invention results in a compatible and stable composition. Hydroquinone is combustible when preheated. 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