(12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT)

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1 (12) INTERNATIONAL APPLICATION PUBLISHED UNDER THE PATENT COOPERATION TREATY (PCT) (19) World Intellectual Property Organization International Bureau (10) International Publication Number (43) International Publication Date WO 2017/ Al 16 March 2017 ( ) P O P C T (51) International Patent Classification: Sanjay; Hindustan Unilever Ltd, Research Centre 64, A61Q 5/06 ( ) A61K 8/98 ( ) Main Road, Whitefield, Bangalore (IN). (21) International Application Number: (74) Agent: WARNER, Guy, Jonathan; Unilever Patent PCT/EP20 16/ Group Olivier van, Noortlaan 120, 3133 AT Vlaardingen (22) International Filing Date: (NL). 30 August 2016 ( ) (81) Designated States (unless otherwise indicated, for every (25) Filing Language: English kind of national protection available): AE, AG, AL, AM, AO, AT, AU, AZ, BA, BB, BG, BH, BN, BR, BW, BY, (26) Publication Language: English BZ, CA, CH, CL, CN, CO, CR, CU, CZ, DE, DK, DM, DO, DZ, EC, EE, EG, ES, FI, GB, GD, GE, GH, GM, GT, (30) Priority Data: HN, HR, HU, ID, IL, IN, IR, IS, JP, KE, KG, KN, KP, KR, September 2015 ( ) EP KZ, LA, LC, LK, LR, LS, LU, LY, MA, MD, ME, MG, (71) Applicant (for all designated States except AE, AG, AU, MK, MN, MW, MX, MY, MZ, NA, NG, NI, NO, NZ, OM, BB, BH, BN, BW, BZ, CA, CY, EG, GB, GD, GH, GM, IE, PA, PE, PG, PH, PL, PT, QA, RO, RS, RU, RW, SA, SC, IL, IN, KE, KN, LC, LK, LS, MT, MW, MY, NA, NG, NZ, SD, SE, SG, SK, SL, SM, ST, SV, SY, TH, TJ, TM, TN, OM, PG, QA, RW, SA, SC, SD, SG, SL, SZ, TT, TZ, UG, TR, TT, TZ, UA, UG, US, UZ, VC, VN, ZA, ZM, ZW. US, VC, ZA, ZM, ZW): UNILEVER N.V. [NL/NL]; (84) Designated States (unless otherwise indicated, for every Weena 455, 3013 AL Rotterdam (NL). kind of regional protection available): ARIPO (BW, GH, (71) Applicant (for AE, AG, AU, BB, BH, BN, BW, BZ, CA, GM, KE, LR, LS, MW, MZ, NA, RW, SD, SL, ST, SZ, CY, EG, GB, GD, GH, GM, IE, IL, IN, KE, KN, LC, LK, TZ, UG, ZM, ZW), Eurasian (AM, AZ, BY, KG, KZ, RU, LS, MT, MW, MY, NA, NG, NZ, OM, PG, QA, RW, SA, SC, TJ, TM), European (AL, AT, BE, BG, CH, CY, CZ, DE, SD, SG, SL, SZ, TT, TZ, UG, VC, ZA, ZM, Z W only): UNI DK, EE, ES, FI, FR, GB, GR, HR, HU, IE, IS, IT, LT, LU, LEVER PLC [GB/GB]; a company registered in England LV, MC, MK, MT, NL, NO, PL, PT, RO, RS, SE, SI, SK, and Wales under company no of Unilever House, SM, TR), OAPI (BF, BJ, CF, CG, CI, CM, GA, GN, GQ, 100 Victoria Embankment, London, Greater London EC4Y GW, KM, ML, MR, NE, SN, TD, TG). 0DY (GB). Declarations under Rule 4.17 : (71) Applicant (for US only): CONOPCO, INC., D/B/A UNI as to applicant's entitlement to apply for and be granted a LEVER [US/US]; 800 Sylvan Avenue AG West, S. Wing, patent (Rule 4.1 7(H)) Englewood Cliffs, New Jersey (US). as to the applicant's entitlement to claim the priority of the (72) Inventors: PAUL, Prem, Kumar, Cheyalazhagan; Uni earlier application (Rule 4.1 7(in)) lever R&D Port Sunlight Quarry Road East, Bebington, Wirral Merseyside CH63 3JW (GB). PYE, Susan; Uni of inventorship (Rule 4.17(iv)) lever R&D Port Sunlight Quarry Road East, Bebington, Published: Wirral Merseyside CH63 3JW (GB). RAUT, Janhavi, with international search report (Art. 21(3)) (54) Title: USE OF SILK PROTEINS FOR HAIR CARE (57) Abstract: Disclosed is a new use of silk proteins in a hair care composition for straightening hair. It has been determined that use of silk proteins, in particular sericin, leads to significant reduction in hair volume.

2 USE OF SILK PROTEINS FOR HAIR CARE Field of the invention The invention relates to hair care products, especially products for straightening hair. Background of the invention The current hair market has a wide range of products meant for temporarily straightening hair. In this context temporarily would mean products, which keep the hair straight for a few days or upto a few weeks and the effect usually wears off gradually. Several hairsprays, mousses, gels, lotions and waxes are commercially available for such purpose. Such materials are generally film forming agents, resins, gums, and/or adhesive polymers. On the other hand, hair straightening compositions meant for permanently straightening the hair are based on the chemical treatment of the hair in a two-step process using thiol-based or hydroxide-based reducing agents followed by neutralisation or oxidation. The natural shape of hair is determined genetically during a keratinisation stage. The hair follicle wall shapes the cells that are produced by hair papilla. These cells are converted into a hard keratin making it difficult to alter the characteristic structure. Any process of curling, waving or straightening hair involves a transformation step in which the hair keratin is softened, reshaped to the desired form or shape, then rehardened to the new desired shape. Permanent straightening results in breaking or disruption of keratin disulphide bonds or linkages. This occurs when hair is treated with an alkali or reducing agent. The extent of straightening depends on the strength and concentration of the reducing agent compound, the contact time and other variable physical parameters

3 like temperature and stress applied to hair during such process. Silk proteins in general, and sericin in particular,have been used in hair care products for several years for diverse applications. Sericin is a type of protein obtained from silk cocoons. This silk cocoons contain two types of proteins; one is sericin and other is fibroin. Typically the amount of sericin in a Bombyx mori cocoon is 25-30% and the balance is fibroin. Silk protein is a kind of protein like collagen, elastin, keratin, fibroin and sporgin which is an essential constituent of cocoon filament. The silk fibre protein is synthesized by silk gland cells and stored in the lumen of the silk glands. Subsequently, it is converted into silk fibres. JP A (Nakano Seiyaku KK, 2010) discloses hair care compositions which keep the hair straight for longer time. The compositions contain sericin which is heat treated and para 25, in particular, discloses that such sericin has a technical effect of imparting antioxidant power to hair. Para 3 1 discloses that a protein composition of hydrolysed keratin with average molecular weight is effective for improving the straight form retention of hair and hair repair effect.. JP A (Nakano Seiyaku KK, 2008) discloses permanent hair straightening composition which has a protein and a silylated hydrolysed protein derived from silk. JP A (Kanebo, 2007) discloses a hair cosmetic which suppresses hair swelling, prevents elution of protein inside the hair, controls roughness and dryness of the hair, improves setting properties and wiriness. The composition inter-alia contains sericin having number-average molecular weight of 5,000-20,000 Da. US A (Somang Cosmetics) discloses a solvent composition for one-step permanent wave and hair straightener comprising amino acid, protein, a reducing agent; an alkaline agent; an amino acid-based surfactant; organic acid; alcohol; and

4 urea. The solvent composition improves the efficiency of curling and straightening hair and the ability to maintain the curled and straightened hair. JP A (Nakano Siyaku, 201 1) discloses hair wax with style-retaining power and good conditioning effects. The hair wax comprises sericin or sericin which is prior hear treated. US A (Chemunion, 2012) discloses the use of sericin nanoparticles prepared in a certain way in cosmetic hair care products for gloss and softness and to promote maintenance of coloration in dyed hair. This publication also backwardly cites several patents which disclose some other use of sericin/silk proteins in hair care products like setting ability, moisture resistance of curl retention, providing a natural feel, protection against environmental, chemical, and grooming associated damage, improvement of hair structure and physical-optical hair properties. The nanoparticles are prepared by coating the particles with cetyltrimethylammonium chloride and behenyltrimethylammonium chloride to change it load surface. The long chain alkyl groups are responsible for deposition on hair surface. Quaternized guar gum is used to prepare the nanoparticles. Therefore, in summary, this application does not disclose that sericin has any technical effect; rather it discloses a technical effect of sericin coated with cationic surfactants. JP A (Seirin) discloses hair treatment composition which ameliorates electrification of the hair without damaging the touch feeling of the hair by improving water retention of hair. The composition contains hydrolyzed sericin. Kerasoin Professional K Liss Spray Protector (Thermal Protector Straightening Spray with Keratin) is a commercially available product which is said to repair and nourish hair tips, assuring good straightening results and shiny hair. According to the manufacturer, keratin interacts with silk protein resulting in smooth, soft hair and an upgraded hair straightening quality, leaving hair smooth and silky. Jequiti Fyo Professional Post-Chemical Reconstruction Conditioner contains a blend of nano-protein sericin, essential amino acids and UV filters. According to the

5 manufacturer, it reconstructs straightened and colour-treated hair to provide elasticity, reduce frizz, prevent hair fall from breakage, hydrate, and give shine and natural balance to the hair. Schwarzkopf's got2b Play It Straight Straightening Blow Dry Kit offers a two-step system to control and tame frizz, and provide easier blow-drying. The product has a smoothing serum which is formulated with keratin, silk and wheat proteins to smooth and straighten the hair whilst making the style more manageable. It also contains a sealing cream having active agents to seal in the straightening effect and long-lasting smoothness for up to ten washes after application. Some of the well-known hair straightening agents include Citric acid and Maltotetraose. EP B 1 (Unilever, 2014) discloses use of a sugar comprising maltotriose and/or maltotetraose to straighten and decrease volume of hair. JP A (Safety Company Ltd) discloses treatment of hair with sericin hydrolysate followed by transglutaminase leads to better wave efficiency and wave retention. It is pertinent to note that the composition of sericin hydrolysate (which can be obtained by alkaline hydrolysis of sericin) is not the same as that of sericin. Both are assigned distinct CAS numbers which indicates that the two are not same. Therefore, this Japanese application discloses an effect of hydrolysed form of sericin, rather than sericin. DE A 1 (Beiersdorf AG) discloses hair cosmetic compositions and cosmetic bath additives containing sericin which provide substantive behaviour towards human hair and human skin a pronounced skin-smoothing effect. The following website explains the difference between smoothening and softening. (

6 Hair smoothing is a hair care treatment that leaves hair smoother and silkier than before without changing the natural hair type. It is mostly just an alignment technique. Hair straightening is primarily a styling method that also untangles unruly locks. This treatment not only makes hair more manageable, but also gives desired straight hair look. However, there is need for newer and better agents for straightening hair. Surprisingly, we have now found a new use of silk proteins, in particular sericin, for hair straightening benefits. This technical effect has been observed on naturally wavy hair swatches that were subjected to hair swatch volume studies during the course of in-vitro assays. Such a use of silk protein and in particular, of sericin, is believed to be new. Summary of the invention In accordance with a first aspect is disclosed use of silk proteins in a hair care composition for straightening hair. In accordance with a second aspect is disclosed a method of straightening hair by applying thereto a hair care composition comprising silk proteins. Detailed description of the invention Silk means the fibers of the cocoon of mulberry silk worm (Bombyx mori). The crude silk fiber consists of a double thread of fibroin. The cementing substance holding these double fibers together is sericin. Silk consists of 70-80% by weight of fibroin, 19-28% by weight of sericin, 0.5-1% by weight of fat and 0.5-1% by weight of dyes and mineral constituents.

7 Sericins represent a family of proteins with a range of molecular weight. They are characterized by a high serine content, -35 mol %. Sericins are soluble in hot water, this property is used to degum the silk fibroin threads. Two genes encode sericins, Ser1 and Ser2. The essential amino acids of sericin are serine (Ser, 37% by weight), aspartate (Asp, 26% by weight), glycine (Gly, 17% by weight), alanine (Ala), leucine (Leu) and tyrosine (Tyr). Silk proteins have been used in hair care compositions for variety of applications. W e have now found a new use for silk proteins. In accordance with a first aspect is disclosed use of silk proteins in a hair care composition for straightening hair, in particular, and preferably, the naturally wavy hair. It is preferred that silk proteins comprise at least 5 % by weight sericin, more preferably at least 25 % sericin. Further preferably, substantially all of said silk proteins is sericin. It is particularly preferred that relative molecular mass (molecular weight) of sericin is from 1 KDa to 50 KDa. Some hair care compositions are designed for therapeutic or medicinal purposes. However, it is preferred that the hair care composition is a cosmetic composition. Nonlimiting examples thereof include hair colouring compositions, shampoos, hair conditioners, styling gels and other products. It is preferred that ph of the compositions is 2.5 to 7. It has been observed that particularly good results are obtained when the composition or the medium in which sericin is applied to hair, has ph in the range of 2.5 to 7. The amount of silk proteins in the composition could be varied to suit the needs of consumers of such products and the extent of hair straightening that is required. However, it is preferred that the amount of silk proteins in the hair care compositions is from 0.5 to 20 wt% and more preferably from 0.5 wt% to 10 wt%. Usually, hair straightening regimen includes a step of application of heat to untreated hair either during or after application of a hair treatment composition. We have found that the use of sericin does not necessarily need application of heat in any manner and

8 nor is this use dependent on the use of any additional excipients. Therefore it is preferred that upon application to the hair to be straightened, the composition is allowed contact time of 2 minutes to 30 minutes therewith. During this time, the ingredient is allowed to interact with hair. It is preferred if the composition is left on hair after application and not immediately washed off (at least for 60 minutes after application). Such products are called "leave on" formulations. Preferred product forms are leave on formulations such as gels, mousses, sprays, creams and aerosols. Creams and mousses are particularly preferred. It is preferred that the ph at 30 C of the composition is from 2.5 to 7. It has been determined that the extent of straightening is inversely proportional to ph. In other words, there is greater straightening at lower ph. It is further particularly preferred that during or after the application, the hair to be straightened are not subjected to any form of heat treatment. Use of hair straightening compositions lead to reduction in hair volume. This is an indicator of the extent of straightening. In other words, straighter hair occupy lesser volume. Usually the volume of wet uncombed hair is lesser than completely dry hair or partially wet but combed hair. We have observed that within the disclosed ph range, even the volume of dry and combed hair is significantly lower than untreated (control) hair. Preferably the volume of straightened hair is not more than 30 % as compared to the volume of un-straightened hair. Un-straightened hair refers to hair which are subjected to straightening by application of silk proteins, preferably in the form of a hair care composition. In other words, the use in accordance with the invention brings about substantial reduction in hair volume. In accordance with a second aspect is disclosed a method of straightening hair by applying thereto a hair care composition comprising silk proteins. It is preferred that the method is a cosmetic method.

9 In accordance with a third aspect is disclosed silk proteins for use in a hair care composition for straightening the hair. In accordance with a fourth aspect is disclosed a hair care composition comprising silk proteins for use in straightening the hair. The compositions may include common conditioning materials such as surfactants, cationic conditioners suitable for hair, quaternary silicone polymers, silicone based conditioners and their emulsions, and amino functional silicones and their emulsions. Silicone based products are particularly preferred. The hair care composition may preferably take the form of a shampoo or hair conditioning composition, or a 2-in-1 conditioning shampoo composition or even any leave-on composition known in the art. Shampoo Compositions Shampoo compositions will nearly always comprise a cleansing surfactant component in an aqueous base. The cleansing surfactant may consist of a single surfactant, usually an anionic surfactant (to provide foam) such as sodium lauryl ether sulphate, or more commonly a mixture of sodium lauryl ether sulphate with a co-surfactant to provide mildness. The most preferred co-surfactant is cocoamidopropyl betaine. The total amount of cleansing surfactant and co-surfactant in a shampoo composition may be from 1 to 50, preferably from 2 to 40, more preferably from 10 to 25 wt%. Compositions comprising more than 25 wt% cleansing surfactant and co-surfactant are considered concentrated shampoos. Examples of suitable anionic cleansing surfactants are the alkyi sulphates, alkyi ether sulphates, alkaryl sulphonates, alkanoyl isethionates, alkyi succinates, alkyi sulphosuccinates, alkyi ether sulphosuccinates, N- alkyl sarcosinates, alkyi phosphates, alkul ether phosphates, and alkyi ether carboxylic acids and salts thereof, especially their sodium, magnesium, ammonium and mono-, di-

10 and triethanolamine salts. The alkyl and acyl groups generally contain from 8 to 18, preferably from 10 to 16 carbon atoms and may be unsaturated. The alkyl ether sulphates, alkyl ether sulphosuccinates, alkyl ether phosphates and alkyl ether carboxylic acids and salts thereof may contain from 1 to 20 ethylene oxide or propylene oxide units per molecule. Specific anionic cleansing surfactants for use in shampoo compositions include sodium oleyl succinate, ammonium lauryl sulphosuccinate, sodium lauryl sulphate, sodium lauryl ether sulphate, sodium lauryl ether sulphosuccinate, ammonium lauryl sulphate, ammonium lauryl ether sulphate, sodium dodecylbenzene sulphonate, triethanolamine dodecylbenzene sulphonate, sodium cocoyl isethionate, sodium lauryl isethionate, lauryl ether carboxylic acid and sodium N-lauryl sarcosinate. Preferred anionic cleansing surfactants are selected from sodium lauryl sulphate and sodium lauryl ether sulphate(n)eo, (where n = 1 to 3); more preferably sodium lauryl ether sulphate(n)eo, (where n = 1 to 3); most preferably sodium lauryl ether sulphate(n)eo where n = 1. The total amount of anionic cleansing surfactant in shampoo compositions I generally ranges from 0.5 to 45, more preferably from 1.5 to 20 wt%. Preferably a shampoo composition comprises a suspending agent. Suitable suspending agents are selected from polyacrylic acids, cross-linked polymers of acrylic acid, copolymers of acrylic acid with a hydrophobic monomer, copolymers of carboxylic acid-containing monomers and acrylic esters, cross-linked copolymers of acrylic acid and acrylate esters, heteropolysaccharide gums and crystalline long chain acyl derivatives. The long chain acyl derivative is desirably selected from ethylene glycol stearate, alkanolamides of fatty acids having from 16 to 22 carbon atoms and mixtures thereof. Ethylene glycol distearate and polyethylene glycol 3 distearate are preferred long chain acyl derivatives, since these impart pearlescence to the composition. Polyacrylic acid is available commercially as Carbopol 420, Carbopol 488 or Carbopol 493. Polymers of acrylic acid cross-linked with a polyfunctional agent may also be used; they are available commercially as Carbopol 910, Carbopol 934,

11 Carbopol 941 and Carbopol 980. An example of a suitable copolymer of a carboxylic acid containing monomer and acrylic acid esters is Carbopol Carbopol 980 is the commonly used suspending agent though there is a growing desire to find an alternative. Suitable cross-linked polymers of acrylic acid and acrylate esters are Pemulen TR1 or TR2. A suitable heteropolysaccharide gum is xanthan gum. Mixtures of any of the above suspending agents may be used. Preferred is a mixture of cross-linked polymer of acrylic acid and crystalline long chain acyl derivative. Suspending agent will generally be present in a shampoo compositions at levels of from 0.1 to 10, preferably from 0.5 to 6, more preferably from 0.9 to 4 wt% of the composition. Generally such suspending agents are present at around 2 wt% of the composition. Shampoo compositions of the invention are generally aqueous, i.e. they have water or an aqueous solution or a lyotropic liquid crystalline phase as their major component. Suitably, the composition will comprise from 50 to 98, preferably from 60 to 90 wt%. Typically, shampoo compositions have ph of around 5.5. The shampoo compositions may also contain conditioning agents. Conditioning agents fall into three classes; silicones, (and cationic deposition polymers to assist in silicone deposition) cationic surfactants and non-silicone oils. Where silicones are included, the composition is likely to also contain a cationic deposition polymer for enhancing deposition of the silicone. Further, a siliconecontaining composition is likely to be lamellar as opposed to isotropic. Isotropic compositions do not deposit silicone effectively. Suitable silicones include polydiorganosiloxanes, in particular polydimethylsiloxanes which have the CTFA designation dimethicone. Also suitable for use in the compositions of the invention are polydimethyl siloxanes having hydroxyl end groups, which have the CTFA designation

12 dimethiconol. A further preferred class of silicones for inclusion in shampoos and conditioners of the invention are amino functional silicones. By "amino functional silicone" is meant a silicone containing at least one primary, secondary or tertiary amine group, or a quaternary ammonium group. Examples of suitable amino functional silicones include polysiloxanes having the CTFA designation "amodimethicone". The total amount of silicone is preferably from 0.01 to 10, more preferably from 0.1 to 5, most preferably 0.5 to 3 % w/w of the composition of the invention. Cationic deposition polymers are used to deposit the silicone to the hair surface and hence enhance performance. Suitable cationic polymers may be homopolymers which are cationically substituted or may be formed from two or more types of monomers. The weight average (Mw) molecular weight of the polymers is generally to 2 million Daltons. The polymers will have cationic nitrogen containing groups such as quaternary ammonium or protonated amino groups, or a mixture thereof. If the molecular weight of the polymer is too low, then the conditioning effect is poor. If too high, then there may be problems of high extensional viscosity leading to stringiness of the composition when it is poured. The cationic nitrogen-containing group will generally be present as a substituent on a fraction of the total monomer units of the cationic polymer. Thus when the polymer is not a homopolymer it can contain spacer non-cationic monomer units. The ratio of the cationic to non-cationic monomer units is selected to give polymers having a cationic charge density in the required range, which is generally from 0.2 to 3.0 meq/g. Suitable cationic polymers include, for example, copolymers of vinyl monomers having cationic amine or quaternary ammonium functionalities with water soluble spacer monomers such as (meth)acrylamide, alkyl and dialkyl (meth)acrylamides, alkyl (meth)acrylate, vinyl caprolactone and vinyl pyrrolidine. The alkyl and dialkyl substituted monomers preferably have C1-7 alkyl groups, more preferably C1-3 alkyl groups. Other suitable spacers include vinyl esters, vinyl alcohol, maleic anhydride, propylene glycol and ethylene glycol. The cationic amines can be primary, secondary

13 or tertiary amines, depending upon the particular species and the ph of the composition. In general secondary and tertiary amines, especially tertiary, are preferred. The cationic polymers can comprise mixtures of monomer units derived from amineand/or quaternary ammonium-substituted monomer and/or compatible spacer monomers. Suitable cationic polymers include, for example cationic diallyl quaternary ammoniumcontaining polymers including dimethyldiallylammonium chloride homopolymer and copolymers of acrylamide and dimethyldiallylammonium chloride, referred to in the industry (CTFA) as Polyquaternium 6 and Polyquaternium 7, respectively; mineral acid salts of amino-alkyl esters of homo-and co-polymers of unsaturated carboxylic acids having from 3 to 5 carbon atoms; and cationic polyacrylamides. Other cationic polymers that can be used include cationic polysaccharide polymers, such as cationic cellulose derivatives, cationic starch derivatives, and cationic guar gum derivatives. Cationic cellulose derivatives include the polymeric quaternary ammonium salts of hydroxyethyl cellulose reacted with lauryl dimethyl ammonium-substituted epoxide, referred to in the industry (CTFA) as Polyquaternium 24. Other suitable cationic polysaccharide polymers include quaternary nitrogen-containing cellulose ethers, and copolymers of etherified cellulose and starch. A particularly suitable type of cationic polysaccharide polymer that can be used is a cationic guar gum derivative, such as guar hydroxypropyltrimethylammonium chloride (commercially available from Rhodia in their JAGUAR series). Examples of such materials are JAGUAR C 13S, C 14, C 15, C17, C16, CHT and C162. Mixtures of any of the above cationic polymers may be used. Cationic polymer will generally be present in shampoo compositions at levels of from 0.01 to 5, preferably from 0.05 to 1, more preferably from 0.08 to 0.5 wt%. Cationic surfactants may be used in 2-in-1 shampoos to provide conditioning benefit. However, since a shampoo composition is likely to also comprise anionic cleansing surfactants, the use of cationic surfactants is limited to compositions where the cationic surfactant is separated from

14 the anionic phase by way of a stable conditioning gel phase made separately from the rest of the formulation and then incorporated afterwards. A fatty alcohol is nearly always included in a conditioning composition and often included in 2-in-1 shampoos. Cetearyl alcohol is one of the preferred examples. Fibre actives are provided to repair or coat the hair fibres. Examples are trehalose (a disaccharide), adipic acid (dicarboxylic acid) and gluconolactone. There are two classes of anti-dandruff actives, namely the azoles and the pyrithiones. Both are active against the target fungi Malassezia spp. The azoles include ketoconazole and climbazole which are fat soluble actives. The pyrithiones include zinc pyrithione (ZPTO) which is insoluble and delivered as a particle to the scalp. Preferably, the anti-dandruff active is present at from 0.01 to 5, more preferably from 0.1 to 2.5 % w/w of the composition of the invention. The compositions may also be hair conditioning compositions (also known as conditioners). Hair conditioning compositions may also be left on the head, i.e. not rinsed off after application. The main ingredients in a hair conditioner are the conditioning actives described above, the main actives being a cationic surfactant (e.g. behenyltrimmonium chloride), a silicone conditioning agent (e.g. aminosilicone (DC 7134)) and a non-silicone oil, and usually a fatty alcohol (e.g. cetearyl alcohol). Antidandruff actives may also be included therein. Suitable cationic surfactants for use in conditioner compositions include cetyltrimethylammonium chloride, behenyltnmethylammonium chloride, cetylpyridinium chloride, tetramethylammonium chloride, tetraethylammonium chloride, octyltrimethylammonium chloride, dodecyltrimethylammonium chloride, hexadecyltrimethylammonium chloride, octyldimethylbenzylammonium chloride, decyldimethylbenzylammonium chloride, stearyldimethylbenzylammonium chloride, didodecyldimethylammonium chloride, dioctadecyldimethylammonium chloride, tallowtnmethylammonium chloride, dihydrogenated tallow dimethyl ammonium chloride (eg, Arquad 2HT/75 from Akzo Nobel), cocotrimethylammonium chloride, PEG-2- oleammonium chloride and the corresponding hydroxides thereof. Further suitable

15 cationic surfactants include those materials having the CTFA designations Quaternium 5, Quaternium 3 1 and Quaternium 1 8. Mixtures of any of the foregoing materials may also be suitable. A particularly useful cationic surfactant for use in conditioners is cetyltrimethylammonium chloride. Another particularly useful cationic surfactant for use in conditioners according to the invention is behenyltrimethylammonium chloride. The level of cationic surfactant will generally range from 0.01 to 10, more preferably 0.05 to 7.5, most preferably 0.1 to 5 wt%. The compositions may contain emulsified droplets of a silicone condition agent, for enhancing conditioning performance as previously described. The cosmetic compositions may also comprise a dispersed, nonvolatile, waterinsoluble, non-silicone oily conditioning agent. Preferably such non-silicone oily conditioning agents are present in the hair conditioning compositions of the invention. By "insoluble" is meant that the material is not soluble in water (distilled or equivalent) at a concentration of 0.1 wt% at 25 C. Suitable non-silicone oils are selected from hydrocarbon oils, fatty esters and mixtures thereof. Straight chain hydrocarbon oils will preferably contain from about 12 to about 30 carbon atoms. Also suitable are polymeric hydrocarbons of alkenyl monomers, such as C2-C6 alkenyl monomers. Specific examples of suitable hydrocarbon oils include paraffin oil, mineral oil, saturated and unsaturated dodecane, saturated and unsaturated tridecane, saturated and unsaturated tetradecane, saturated and unsaturated pentadecane, saturated and unsaturated hexadecane, and mixtures thereof. Branched-chain isomers of these compounds, as well as of higher chain length hydrocarbons, can also be used. Suitable fatty esters are characterised by having at least ten carbon atoms, and include esters with hydrocarbyl chains derived from fatty acids or alcohols, Monocarboxylic acid esters include esters of alcohols and/or acids of the formula R'COOR in which R' and R independently denote alkyl or alkenyl radicals and the sum of carbon atoms in R' and R is at least 10, preferably at least 20. Di- and trialkyl and alkenyl esters of carboxylic acids can also be used. Particularly preferred fatty esters are mono-, di- and

16 triglycerides, more specifically the mono-, di-, and tri-esters of glycerol and long chain carboxylic acids such as C 1 -C22 carboxylic acids. Preferred materials include cocoa butter, palm stearin, sunflower oil, soya bean oil and coconut oil. The oily conditioning agent is suitably present at a level of from 0.05 to 10, preferably from 0.2 to 5, more preferably from about 0.5 to 3 wt%. Hair conditioning compositions typically also incorporate a fatty alcohol. The combined use of fatty alcohols and cationic surfactants in conditioning compositions is believed to be especially advantageous, because this leads to the formation of a lamellar phase, in which the cationic surfactant is dispersed. Representative fatty alcohols comprise from 8 to 22 carbon atoms, more preferably 16 to 22. Fatty alcohols are typically compounds containing straight chain alkyl groups. Examples of suitable fatty alcohols include cetyl alcohol, stearyl alcohol and mixtures thereof. The use of these materials is also advantageous in that they contribute to the overall conditioning properties of compositions of the invention. The level of fatty alcohol in the hair conditioning compositions of the invention will generally range from 0.01 to 10, preferably from 0.1 to 8, more preferably from 0.2 to 7, most preferably from 0.3 to 6 wt%. The weight ratio of cationic surfactant to fatty alcohol is suitably from 1: 1 to 1:10, preferably from 1: 1.5 to 1:8, optimally from 1:2 to 1:5. If the weight ratio of cationic surfactant to fatty alcohol is too high, this can lead to eye irritancy from the composition. If it is too low, it could make the hair feel squeaky. When the cosmetic composition is a hair colour composition, it may be in the form of a gel, cream, mask, ointment, mousse or lotion. The following non-limiting examples further illustrate the preferred embodiments of the invention. All percentages referred to in the examples and throughout this specification are by weight based on total weight unless otherwise indicated. Examples Example 1: Hair orientation done by the RUMBA technique

17 RUMBA is a technique for quantifying orientation of hair fibers and is performed on hair swatches. It measures the orientation of hair fibres using polarization imaging for each pixel of the image. Single fibre imaging is also possible. At the level of single pixel level, each hair fibre can be locally decomposed into a linear direction defined by an angle versus the vertical direction that can be colour coded. A software allows the measurement, followed by complete analysis (numerical data, histogram and images). RUMBA acquires multiple polarization images in less than one second which makes it easy to extract the hair fibres from the background, thereby allowing the volume to be calculated. More information is available from the website The test procedure is summarized below. Dark brown European wavy #6 swatches (2 g weight and 25 cm length) were soaked for twenty minutes in a 2% aqueous solution of sericin followed by rinsing the treated swatches with water for thirty seconds. They were then dried at room temperature. The alignment coefficients were measured for each swatch following the RUMBA method. The data is summarised in table 1. A higher coefficient implies more alignment. When compared to untreated hair, this would mean straighter hair. Table 1 Note: Sericin-1 was procured from Seidecosa, India. Its relative molecular mass (molecular weight) was in the range of 2 to 3 KDa. Sericin-2 was procured from Xintiansi Bio-Tech, China and its molecular weight was 5 KDa.

18 The data in table 1 clearly indicates that hair swatches treated with sericin were straighter than untreated hair. Example 2 : Volume of treated hair swatches before and after combing Here volume refers to the projection of the swatch image on to the screen and is represented in mm 2. Dark brown European wavy #6 swatches (2 g weight and 25 cm length) were dipped in 2% aqueous solution of sericin for 20 minutes. This experiment was conducted using two different grades of sericin as done earlier. After treating the swatches for 20 minutes, the swatches were rinsed with cold water, dried and combed. The swatches were not exposed to any form of heart during or after the application of sericin. The results are summarised in table 2. Table 2 Note: * % reduction compared to the respective before and after combing data of untreated The data in table 2 clearly indicates the extent of reduction in the volume of hair brought about by sericin as compared to untreated hair. Even after combing the hair, where usually there is an increase in hair volume, the volume of hair treated with sericin from either source remained much less than the corresponding volume of untreated uncombed hair. Example 3 : Hair swatch volume study (rice protein v/s sericin-2)

19 In this example, sericin-2 was compared against rice protein in the manner described earlier. The results are summarised in table 3. Table 3 Note: * %reduction compared to the respective before and after combing data of untreated hair The data in table 3 clearly indicates the extent of reduction in volume brought about by rice protein as compared to untreated hair. The data also indicates the extent of reduction brought about by sericin (sericin-2). Example 4 : Effect of ph The ph of medium plays an important role. In order to find out the precise effect of ph, some experiments using the same Dark brown European wavy #6 swatches were done at various ph. The results are summarised in table 4. The ph of native sericin was 5.5. This was lowered by adding dilute hydrochloric acid to the aqueous solution.

20 Table 4 Note: * % reduction compared to the respective before and after combing data of untreated The data in table 4, in general, further reinforces the effect of sericin. There is more straightening at lower ph. In other words, there is more reduction in hair volume when compared to untreated hair.

21 Claims 1. Use of silk proteins in a hair care composition for straightening hair. 2. Use as claimed in claim 1 wherein said silk proteins comprise at least 5% by weight sericin. 3. Use as claimed in claim 2 wherein substantially all of said silk proteins is sericin. 4. Use as claimed in claim 2 or 3 wherein relative molecular mass of said sericin is from 1 KDa to 50 KDa. 5. Use as claimed in any one of the preceding claims 1 to 4 wherein said hair care composition is a cosmetic composition. 6. Use as claimed in claim any one of the preceding claims 1 to 4 wherein ph of said composition is 2.5 to Use as claimed in any one of the preceding claims 1 to 6 wherein the amount of silk proteins in said composition is 0.2 to 20 wt%. 8. Use as claimed in any one of the preceding claims 1 to 7 wherein, upon application to the hair to be straightened, said composition requires a contact time of 2 minutes to 30 minutes therewith. 9. Use as claimed in claim 8 wherein during or after said application, said hair to be straightened are not subjected to any form of heat treatment. 10. Use as claimed in any one of the preceding claims 1 to 9 wherein said use brings about at least 30 % reduction in volume of un-straightened hair A method of straightening hair by applying thereto a hair care composition comprising silk protein.

22 A. CLASSIFICATION O F SUBJECT MATTER INV. A61Q5/06 A61K8/98 ADD. According to International Patent Classification (IPC) or to both national classification and IPC B. FIELDS SEARCHED Minimum documentation searched (classification system followed by classification symbols) A61Q A61K Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched Electronic data base consulted during the international search (name of data base and, where practicable, search terms used) EPO-Internal, WPI Data, CHEM ABS Data C. DOCUMENTS CONSIDERED TO B E RELEVANT Category* Citation of document, with indication, where appropriate, of the relevant passages Relevant to claim No. X J P A (SAFETY CO LTD) 1-8, 10, 17 March 2005 ( ) 11 exampl e 1 page 11 X DE Al (BEI ERSD0RF AG [DE] ) March 1984 ( ) c l aims 1, 2 tabl e on page 3 page 5, paragraph 2 page 6, paragraph 4 exampl e s 1-9 X J P A (NAKAN0 SEIYAKU KK) September 2010 ( ) c i ted i n the appl i cati on paragraphs [0018], [0028], [0029] -/-- X Further documents are listed in the continuation of Box C. See patent family annex. * Special categories of cited documents : "A" document defining the general state of the art which is not considered to be of particular relevance "T" later document published after the international filing date or priority date and not in conflict with the application but cited to understand the principle or theory underlying the invention "E" earlier application or patent but published o n or after the international "X" document of particular relevance; the claimed invention cannot be filing date considered novel or cannot be considered to involve an inventive "L" documentwhich may throw doubts on priority claim(s) orwhich is step when the document is taken alone cited to establish the publication date of another citation or other "Y" document of particular relevance; the claimed invention cannot be special reason (as specified) considered to involve an inventive step when the document is "O" document referring to an oral disclosure, use, exhibition or other combined with one o r more other such documents, such combination means being obvious to a person skilled in the art "P" document published prior to the international filing date but later than the priority date claimed "&" document member of the same patent family Date of the actual completion of the international search Date of mailing of the international search report 27 September /10/2016 Name and mailing address of the ISA/ Authorized officer European Patent Office, P.B Patentlaan 2 NL HV Rijswijk Tel. (+31-70) , Fax: (+31-70) Lenzen, Achim

23 C(Continuation). DOCUMENTS CONSIDERED TO BE RELEVANT Category* Citation of document, with indication, where appropriate, of the relevant passages Relevant to claim No. US 2012/ Al (VELAZQUEZ PEREDA MARIA 1-11 DEL CARMEN [BR] ET AL) 28 June 2012 ( ) c i ted i n the appl i cati on paragraphs [0017], [0042] - [0048]

24 Patent document Publication Patent family Publication cited in search report date member(s) date J P NONE DE A l DE A l P S A P A NONE US A l EP A l US A l O A l