388, 7381 (2010), H. Li, G. Hu, F. Guo, L. Zhao, J. Zhu, Y. Zhang, Can. 338, 217223 (2013), S. H. Ali, F. S. Al-Mutairi, M. A. Fahim, Fluid Phase Equilib. The aquatic toxicity of hydroquinone to fresh water fish, Daphnia, and algae was between 0.050- . - 65.21.225.73. The obtained results show that the . Compositions according to this invention may include dermatologically acceptable carriers. The protective system can be an entrapment system, a single or multi-laminar system, such as by formation of vesicle, such as a liposome, or by utilizing wax, paraffin, silicone, polyethylene or any material or system which protects the retinoid from oxidation. This complex dissolves in hot water, where the two molecules dissociate in solution. 57, 295300 (2013), R. F. Pires, M. R. Franco Jr, Fluid Phase Equilib. Glycerol and citric acid, non-toxic and renewable reagents, were crosslinked by a melt polymerization reaction at temperatures from 90-150C. [21] The FDA officially banned hydroquinone in 2020 as part of a larger reform of the over-the-counter drug review process. ;O,1Y+%8#oKT^VWtew4>@V.SR :hmBZ>#ey!UC5! / /n Except where otherwise noted, data are given for materials in their, Hydroquinone oxidation with V2O5/NaClO3/H2SO4, http://www.sciencemadness.org/smwiki/index.php?title=Hydroquinone&oldid=11523, Articles containing unverified chemical infoboxes, GNU Free Documentation License 1.3 or later. I understand the concentrations are high but I have used them before, its just too expensive to keep buying from a compounding pharmacy. 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. vz >I d50dwp?i4,H3. On this Wikipedia the language links are at the top of the page across from the article title. Reference Tables: SOLUBILITIES - uspbpep.com A further embodiment of the invention includes a method for stabilizing a hydroquinone composition (with about 1% to about 12% hydroquinone, preferably about 2% to about 10%, more preferably about 2% to about 8%, and most preferably about 3% to about 4%) with a neutral pH of 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, by adding a water-soluble antioxidant, preferably sulfite, including but not limited to sulfites, bisulfites, metabisulfites, their salts and their derivatives, most preferably sodium metabisulfite, and a cationic salt of acidic ascorbyl esters, preferably sodium ascorbyl phosphate, more preferably aminopropyl ascorbyl phosphate, most preferably magnesium ascorbyl phosphate. N')].uJr . 58 / Monday, March 26, 2012 / Rules and Regulations 10/31/2017 EN (English US) 6/8 12.3. Gravimetric method is used to measured hydroquinone solubility in water, ethanol and in water+ethanol binary mixtures at temperatures (293.15, 295.15, 298.15, 300.15, 303.15, 305.15, 308.15, 310.15 and 313.15)K. Mole fractions solubility of hydroquinone are correlated with temperature by using the Apelblat equation. Some hydroquinone compositions include antioxidants, such as ascorbyl palmitate. Cookie Notice Hydroquinone is a white crystalline solid, poorly soluble in water, but more soluble in organic solvents. It does not have the same predisposition to cause dermatitis as metol does. Some documentation and label information may refer to the legacy brand. This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions. 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. 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. S.C. Gad, T. Pham, in Encyclopedia of Toxicology (Third Edition), 2014 Environmental Fate and Behavior. Phase A is added to the tank, which is held at a temperature of from about 70 to about 75 C, and in which a CO. Substituted derivatives of this parent compound are also referred to as hydroquinones. 115, 22772285 (2014), Article [31], Hydroquinones are one of the two primary reagents in the defensive glands of bombardier beetles, along with hydrogen peroxide (and perhaps other compounds, depending on the species), which collect in a reservoir. The combined nearly ideal binary solvent (NIBS)-Redlich-Kister equation is . Some may double boil the hydroquinone and ester, I was too scared of the possibility of combustion. If youre making your lotion. HlRMo0WB:NnVCnE4(i0 (1* )@NzHR!>i;8XaXnsO0LNT0l$B%"NAb0I9V *6/-\vn0W"fKF:AAgl:psRZ?k`&eB IUQ0ET;W#vL=@XwRG{-LHlTz]^s%OB(GF 11'I https://doi.org/10.1007/s10765-020-02750-4. We apologize! Hydroquinone, like phenols are very weak acids and can be deprotonated. Canon 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. In 1-octanol, the decreasing order of the solubility of these compounds is as follows: resorcinol>benzoic acid>salicylic acid>hydroquinone. Color stability improvement is evident at all levels. %PDF-1.4 % [Na+].OC[C@H](O)[C@H]1OC([O-])=C(OP([O-])([O-])=O)C1=O, N1=CC(C(=O)OCC)=CC=C1C#CC1=CC=C(SCCC2(C)C)C2=C1, C1=C(C(O)=O)C=CC2=CC(C3=CC=C(C(=C3)C34CC5CC(CC(C5)C3)C4)OC)=CC=C21, CC(=O)OC1=C(C)C(C)=C2O[C@@](CCC[C@H](C)CCC[C@H](C)CCCC(C)C)(C)CCC2=C1C, disodium;2-[2-[carboxylatomethyl(carboxymethyl)amino]ethyl-(carboxymethyl)amino]acetate, [Na+]. 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 . PDF Solubilityof Eastman hydroquinone andderivatives All Rights Reserved, View All Eastman Hydroquinone USP Articles. [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+]. 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 Stir until uniform. 0000002585 00000 n This is a prescription-only ingredient in some countries, including the member states of the European Union under Directives 76/768/EEC:1976. Calorim. The composition is preferably formulated in separate phases as designated below. One skilled in the art is familiar with the known protective system technologies, such as encapsulation and entrapment methodologies. These phases (described below) are combined in a mixing tank with an in-line homogenizer as follows. [24], Numerous studies have revealed that hydroquinone, if taken orally, can cause exogenous ochronosis, a disfiguring disease in which blue-black pigments are deposited onto the skin; however, skin preparations containing the ingredient are administered topically. Additionally, the hydroquinone compositions frequently discolor over time and turn from a whitish color to a brown or even black. The Boiling Point of hydroquinone is 287C Also, the Melting Point of hydroquinone is 172C. 0 7 r @ &. I've been presented with the problem of trying to dissolve Hydroquinone in a solvent other than water. Eastman Hydroquinone, USP Grade is for skin-lightening products to address hyperpigmentation. [23] This conclusion was reached based on the extent of absorption in humans and the incidence of neoplasms in rats in several studies where adult rats were found to have increased rates of tumours, including thyroid follicular cell hyperplasias, anisokaryosis (variation in nuclei sizes), mononuclear cell leukemia, hepatocellular adenomas and renal tubule cell adenomas. 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. Hydroquinone (EHC 157, 1994) - International Programme on Chemical Safety 108. hydroquinone, 1,4-benzenediol, quinol, 1,4-dihydroxybenzene, p-benzenediol, 4-hydroxyphenol, p-hydroquinone, p-hydroxyphenol, p-dihydroxybenzene, benzoquinol, Electrophoresis, Western Blotting and ELISA, Chromatography and Mass Spectrometry Reagents, Laboratory Syringe Needles and Accessories, Lab Coats, Aprons, and Other Safety Apparel, Sharps Disposal Containers and Accessories, Classroom Laboratory Supplies and Consumables, Applied Biosystems TaqMan Assay and Arrays Search Tool, Applied Biosystems TaqMan Custom Assay Design Tools, Applied Biosystems Custom qPCR Primers and TaqMan Probes Tool, Chemical Storage and Management Resource Center, Solubility in water: 70g/L in water (20C). 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. The experimental solubility data was well-correlated with the data, calculated by . The solubility in water is 6.72g/L. 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. 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. Environ. The 10 Best Hydroquinone Creams to Buy in 2023 - Beauty Mag However, a problem with a formulation containing both retinoids and hydroquinone has been their incompatible pH ranges. An acceptable carrier also possesses suitable aesthetic and cosmetic qualities and may include emollients, conditioners and the like. Fill out the form below, and we will send you the document as soon as we can! Data 53, 199200 (2008), N. Sunsandee, S. Suren, N. Leepipatpiboon, M. Hronec, U. Pancharoen, Fluid Phase Equilib. [17], An important reaction is the conversion of hydroquinone to the mono- and diamine derivatives. 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%. Google Scholar, A.-C. Huang, Y.-K. Chuang, C.-F. Huang, C.-M. Shu, J. Therm. https://doi.org/10.1007/s10765-020-02750-4, DOI: https://doi.org/10.1007/s10765-020-02750-4. 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%. . Exceptional antioxidant qualities are seen at 0.10% (all percentages in the application are weight percent) and above, preferably from about 0.05% to about 0.5% for sodium metabisulfite. application/pdf Azelaic acid (AzA) is a organic compound with the formula HOOC(CH 2) 7 COOH. For more information, please see our 0000053439 00000 n 0000003430 00000 n Can be destroyed by oxidizing it with an oxidizing mixture. 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. 250, 165172 (2006), F. L. Mota, A. J. Queimada, A. E. Andreatta, S. P. Pinho, E. A. Macedo, Fluid Phase Equilib. Sodium metabisulfite has the added advantage that it does not discolor by oxidation. Hydroquinone is an aromatic organic compound which is currently used in two main sectors: . With respect to organic solvents, the solubility varies from 57% in ethanol to less than 0.1% in benzene. RJPT - Hydroquinone Solubility in Pure and Binary Solvent Mixture at For a shipping quote, check the box and the bottom and provide us your shipping information. Variations in pH have proven to result in excessive discoloration ranging from brownish to black. 2017-02-16T10:10:56+01:00 The Molecular Weight is 110.11 g/mol. 420, 2429 (2016), W. E. Acree Jr, Thermochim Acta 189, 3756 (1991), F. L. Nordstrm, . C. Rasmuson, J. Chem. One embodiment of the invention is a composition which comprises hydroquinone (about 1% to about 12%, preferably about 2% to about 10%, more preferably about 2% to about 8%, more preferably with about 2% to about 4%, and most preferably about 3% to about 4%) and has a neutral pH of 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. Solute (1 g) Water Boiling Water Alcohol Chloroform Ether Other Acenocoumarol 67,000 280 130 1800 Acetaminophen 20 10 1 N sodium hydroxide, 15 Acetohexamide 230 210 Acetylcysteine 5 4 Acetyldigitoxin 6100 62.5 12 >10,000 Ammonium Alum 7 0.5 Aluminum Chloride 0.9 4 Aluminum Sulfate 1 Amantadine Hydrochloride 2.5 5.1 18 polyethylene glycol 400, 70 You can expect to hear back from a ChemPoint product specialist within 1 business hour. V)gB0iW8#8w8_QQj@&A)/g>'K t;\ $FZUn(4T%)0C&Zi8bxEB;PAom?W= C6H4O2) is formed. Solubility of Hydroquinone. valproic acid having a carboxyl group bound to a chain of seven or more carbon atoms, e.g. Without being limited to the mechanism of this discoloration, it is believed that the discoloration may be caused at least in part by oxidation of the hydroquinone. Eng. 88, 161164 (2010), J. Delgado, Int. 20grams ofhydroquinonein 20oz is liquid is 10%. We have discovered that a hydroquinone composition (with about 1 to about 12% hydroquinone, preferably with about 2% to about 10%, more preferably with about 2% to about 8%, more preferably with about 2% to about 4%, most preferably with about 3% to about 4% hydroquinone) with preferably a pH of 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, can include cationic salts of acidic ascorbyl esters, preferably sodium ascorbyl phosphate, more preferably aminopropyl ascorbyl phosphate, most preferably magnesium ascorbyl phosphate as an antioxidant and the color destabilization problems are appreciably less as compared to hydroquinone compositions without such a cationic salt of acidic ascorbyl esters in the neutral pH range: preferably a pH of 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. Tests, which results are detailed in the following two tables, are performed at 5C and 40C for certain percentages of magnesium ascorbyl phosphate at specific pHs. Hydroquinone can be made through several routes. COMMON BRAND NAME (S): Aclaro, Aclaro PD, Alera, Alphaquin HP, Alustra, Claripel, Complex B . Thanks to the added vitamin E, it leaves your skin feeling smooth and soft, too. It exerts a depigmenting effect on skin of mammals by increasing the excretion of melanin from the melanocytes. Classical photo shops also sell hydroquinone. AzA inhibits tyrosinase. EP2047846A2 - Process for stabilizing hydroquinone - Google In the United States, the most commonly used treatment for hyperpigmentation is 1,4-benzenediol, which is known as hydroquinone. . I'd like the consistency to be thin like a gel so that it absorbs quicker. Place an order online, track your orders, download SDS and TDS, and see your quotes, all in one secure place. However, hydroquinone discolors at the pH range of 7.0 to 8.5. The toxicology of hydroquinone - relevance to occupational and environmental exposure. It would be desirable to combine the pigmentation disorder treatment with this skin benefit ingredient in one composition. The reservoir opens through a muscle-controlled valve onto a thick-walled reaction chamber. What is Hydroquinone: Properties, Uses and Applications, Examples Conversion factors (at 25 oc and normal atmospheric pressure) 1 ppm = 4.5 mg!m 3 Determination and Correlation of Solubilities of Benzoic Acid As utilized herein, the inhibition of the retinoid oxidation should be sufficient to prohibit browning of the composition for its shelf life, preferably greater than about six months, more preferably greater than about twelve months, and most preferably greater than about eighteen months. So, does anybody know of another solvent I could use that has a higher . endstream endobj 382 0 obj << /Type /FontDescriptor /Ascent 891 /CapHeight 656 /Descent -216 /Flags 34 /FontBBox [ -558 -307 2034 1026 ] /FontName /BCGJCE+TimesNewRoman,Bold /ItalicAngle 0 /StemV 160 /XHeight 0 /FontFile2 389 0 R >> endobj 383 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 181 /Widths [ 250 0 0 0 0 0 0 278 333 333 500 0 250 333 250 278 500 500 500 500 500 500 500 500 500 500 333 333 0 570 0 0 0 722 667 722 722 667 611 778 778 389 500 778 667 944 722 778 611 778 722 556 667 722 722 1000 722 722 0 333 0 333 0 0 0 500 556 444 556 444 333 500 556 278 333 556 278 833 556 500 556 556 444 389 333 556 500 722 500 500 444 0 0 0 0 0 0 0 0 0 0 0 500 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 500 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 576 ] /Encoding /WinAnsiEncoding /BaseFont /BCGJCE+TimesNewRoman,Bold /FontDescriptor 382 0 R >> endobj 384 0 obj << /Type /FontDescriptor /Ascent 929 /CapHeight 0 /Descent -249 /Flags 32 /FontBBox [ -184 -249 1037 929 ] /FontName /BCGKAB+ImprintMT-Shadow /ItalicAngle 0 /StemV 0 /FontFile2 390 0 R >> endobj 385 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 122 /Widths [ 250 0 0 0 0 0 0 0 323 323 0 0 0 375 240 0 510 427 510 510 0 510 0 510 510 510 0 0 0 0 0 0 0 729 0 729 0 698 0 0 854 0 0 0 0 927 802 813 0 0 0 604 0 0 0 0 802 0 0 0 0 0 0 0 0 448 552 0 552 448 0 0 573 271 0 0 271 875 573 500 0 552 375 0 323 573 0 0 0 500 448 ] /Encoding /WinAnsiEncoding /BaseFont /BCGKAB+ImprintMT-Shadow /FontDescriptor 384 0 R >> endobj 386 0 obj << /N 3 /Alternate /DeviceRGB /Length 2575 /Filter /FlateDecode >> stream English, J.C. and Deisinger, P.J. 0000004433 00000 n Please sign in to view account pricing and product availability. Chem. Hydroquinone IS a white crystalline substance when pure and is highly soluble in water. Hydroquinone - an overview | ScienceDirect Topics Google Scholar, W. J. Weber Jr, Y.-P. Chin, C. P. Rice, Water Res. 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. This chamber is lined with cells that secrete catalases and peroxidases. Correspondence to Do not put this product in the microwave. This compound is gathered from the beaver's castor sacs.[35]. 2y.-;!KZ ^i"L0- @8(r;q7Ly&Qq4j|9 I can't use water because I cannot dissolve enough Hydroquinone into it to reach the desired concentration. 2008-2023 ChemPoint. Hydroquinone is combustible when preheated. Thank you for your inquiry and interest in ChemPoint. Hydroquinone is sold by chemical suppliers. sulfur acids, imidic, hydrazonic, hydroximic acids, Carboxylic acids, e.g. Int J Thermophys 42, 1 (2021). Hydroquinone is combustible when preheated. The drug is freely soluble in water and in alcohol. Data 53, 12781282 (2008), A. A common route involves hydroxylation of phenol. Hydroquinone, 99.5%, Thermo Scientific Chemicals Hydroquinone - an overview | ScienceDirect Topics Antioxidants, preferably sulfites, including but not limited to sulfites, bisulfites, metabisulfites, their salts, and their derivatives, most preferably sodium metabisulfite, have been used to stabilize certain compositions, which have included hydroquinone. This is a preview of subscription content, access via your institution. GHS P Statement: Wear protective gloves/protective clothing/eye protection/face protection.Call a POISON CENTER or doctor/physician if you feel unwell.IF ON SKIN: Gently wash with plenty of soap and water.IF IN EYES: Rinse cautiously with water for several minutes. Additionally, a water-soluble antioxidant, preferably a sulfite, including but not limited to sulfites, bisulfites, metabisulfites, their salts and their derivatives, most preferably sodium metabisulfite, may be helpful in stabilizing the hydroquinone composition. It is a reducing agent that is reversibly oxidized to semiquinone and quinone. An improvement in the color stability of the 4% hydroquinone compositions is seen at and above 2.0% magnesium ascorbyl phosphate in the 6-7 pH range. endstream endobj 277 0 obj <>stream Why we like it: This affordable cream contains 2 percent hydroquinone, sunscreen, and costs around five dollars. Hydroquinone undergoes oxidation under mild conditions to give benzoquinone, process which is reversible. : Metabolism and disposition of hydroquinone in Fischer 344 rats after oral or dermal administration. 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. Solubility of Hydroquinone in Different Solvents from 276.65 K to 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. :hS-g"s2Sj Ij=x'V]gPV8tt~qkAVXi|u}5;#.pl-/4JFQ.EP3&F.qa2hI{N qBmG(z#n [GN.}aazN(~8kux9#tnYwIHFuxW v9UNj&ffNW_\\Tc""8=_"7wC>svwQy\^4gF H][QzmlOI(B@ U4[Xb0,|m0*D"/#$\u(QI)RYg\;8 Yjh Hydroquinone Revision Date 24-Dec-2021 General Advice If symptoms persist, call a physician. D7VJV//KZ&t}JSW/L@,l@^ D@ @8 i W `^;V rD}25p>.Bv1}\_E p9 endstream endobj 392 0 obj 1303 endobj 376 0 obj << /Type /Page /Parent 350 0 R /Resources 377 0 R /Contents 381 0 R /MediaBox [ 0 0 595 842 ] /CropBox [ 0 0 595 842 ] /Rotate 0 >> endobj 377 0 obj << /ProcSet [ /PDF /Text ] /Font << /TT2 379 0 R /TT4 383 0 R /TT6 385 0 R >> /ExtGState << /GS1 387 0 R >> /ColorSpace << /Cs6 378 0 R >> >> endobj 378 0 obj [ /ICCBased 386 0 R ] endobj 379 0 obj << /Type /Font /Subtype /TrueType /FirstChar 32 /LastChar 252 /Widths [ 250 0 408 500 0 833 778 180 333 333 500 564 250 333 250 278 500 500 500 500 500 500 500 500 500 500 278 278 564 564 564 444 921 722 667 667 722 611 556 722 722 333 389 722 611 889 722 722 556 722 667 556 611 722 722 944 722 722 611 333 0 333 0 500 0 444 500 444 500 444 333 500 500 278 278 500 278 778 500 500 500 500 333 389 278 500 500 722 500 500 444 0 0 0 541 0 0 0 0 0 0 0 500 0 0 0 0 0 0 0 0 0 0 0 333 0 0 0 500 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 400 0 0 0 0 576 0 0 0 0 0 0 0 750 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 722 0 0 0 0 0 722 0 0 500 444 0 0 0 444 0 0 0 444 444 0 0 0 0 0 0 0 0 0 0 500 0 500 0 0 0 0 0 500 ] /Encoding /WinAnsiEncoding /BaseFont /BCGIOE+TimesNewRoman /FontDescriptor 380 0 R >> endobj 380 0 obj << /Type /FontDescriptor /Ascent 891 /CapHeight 656 /Descent -216 /Flags 34 /FontBBox [ -568 -307 2028 1007 ] /FontName /BCGIOE+TimesNewRoman /ItalicAngle 0 /StemV 94 /XHeight 0 /FontFile2 388 0 R >> endobj 381 0 obj << /Length 462 /Filter /FlateDecode >> stream Methylaminophenol, used in photography, is produced in this way:[8]. 0000002379 00000 n 230, 176183 (2005), A. Apelblat, E. Manzurola, N. A. Balal, J. Chem. The preferred form of protected retinol is manufactured by SunSmart (also known as Particle Sciences, Inc. of Bethlehem, PA) under the brand name of SunCaps A-1283. While the hydroquinone is effective for the pigmentation disorder treatment, retinoid is used for its skin treatment benefits. Magnesium ascorbyl phosphate (also called magnesium ascorbityl phosphate or magnesium L-ascorbyl-2-phosphate) has a chemical formula of C. In another embodiment, sodium metabisulfite and magnesium ascorbyl phosphate are used in about 0.01% (preferably from about 0.05% to about 0.5%, most preferably at least about 0.1%,) and about 0.5% (preferably from about 0.25% to about 3%, more preferably from about 0.25% to about 1%, and most preferably at least about 0.5%) respectively in a composition with about 4% hydroquinone. Methods and products for nucleic acid production and delivery, Nucleic acid product and its administration method, Nucleic acid product and method of administration thereof, Compositions and systems for the treatment of hyperpigmentation, Methods for prevention of post-inflammatory hyperpigmentation, Skin care compositions containing retinoids, Improved method for stability of ageing comprising thirosinase inhibitor activity, Use of ascorbic acid to reduce irritation of topically applied active ingredients, COSMETIC COMPOSITIONS WITH ANTIMICOTIC PROPERTIES, EFFECTIVE AGAINST PSORIASIS AND HAIR LOSS AND COSMETIC METHOD FOR, Treatment or prevention of undesired skin pigmentation, Skin care compositions and method of improving skin appearance, Ultrasound enhancement of percutaneous drug absorption, Skin whiteners containing hydroxytetronic acid, Stabilized retinoid-containing skin care compositions, Retinoid compositions containing a water soluble antioxidant and a chelator, Composition and method for treating rosacea and sensitive skin with free radical scavengers, Skin care compositions containing imidazoles and retinoids, Stable compositions containing a retinoid and an enzyme based antioxidant system, Self-tanning compositions containing dha and propolis extract, Composition and process for stabilizing oxygen-unstable species, Bleaching preparation and cosmetic for preventing and improving aging of skin, Composition and method for the treatment of pigmentation disorders, Composition for cosmetic or pharmaceutical use, Remedies for pigmentation and melanocyte proliferation inhibitors, Public reference made under article 153(3) epc to a published international application that has entered the european phase, Divisional application: reference to earlier application, Information on the status of an ep patent application or granted ep patent.