Hair care composition

Abstract

1. A hair care composition comprising: a) a piroctone compound; and 5b) a cationic homopolymer and / or copolymer comprising an acrylamidopropyltrimonium moiety, wherein the homopolymer and / or copolymer has a charge density of at least 3.5 meq / g.

Description

[Technical Field]

[0001] This invention relates to hair care compositions, particularly anti-dandruff shampoo compositions. [Background technology]

[0002] Hair care compositions generally provide cleansing or conditioning benefits, or a combination of both. Such compositions typically contain one or more cleansing surfactants that generally help to cleanse hair and scalp free of undesirable dirt, particles, and grease.

[0003] Dandruff is a problem affecting many people around the world. This condition manifests as clumps of dead skin cells shedding from the scalp. These are white and give an aesthetically unpleasant appearance. Factors contributing to dandruff include certain members of Malassezia yeast. To combat these, hair treatment compositions containing various active substances for dandruff prevention have been developed. Piroctone compounds, such as piroctone olamine, are one such active substance.

[0004] A common problem with piroctone compounds is their difficulty in deposition onto hair or scalp during the washing process. This is especially true when effective anionic cleansing surfactants, such as sodium laureth sulfate, are present in the composition. During excessive rinsing, most of the piroctone is easily washed away along with the surfactant. Poor deposition correlates with low anti-dandruff activity, and therefore little mitigation of the adverse effects of dandruff. To date, there have been attempts to compensate for this drawback by increasing the amount of piroctone olamine in hair treatment compositions. Such methods lead to various problems, including increased costs, potential instability of the formulation, and potential adverse effects on the feel of the hair. Therefore, it is not a preferred method in the industry.

[0005] Cationic polymers are used to enhance the deposition of conditioning agents and / or anti-dandruff agents on the hair and / or scalp. These polymers may be synthetic or natural polymers modified with cationic substituents.

[0006] This invention relates to improving the deposition of piroctone compounds (Octopirox) using a cationic polymer having a specified charge density. [Overview of the Initiative] [Means for solving the problem]

[0007] In the first embodiment, the present invention is a) Piroctone compounds and, b) Homopolymers and / or copolymers comprising an acrylamidopropyltrimonium moiety, wherein the polymer and / or copolymer has a charge density of at least 3.5 meq / g and a weight-average molecular weight (g / mol) of 100,000 to 500,000 at pH 7. This relates to a hair care composition containing [specific components].

[0008] In a second aspect, the present invention relates to a cosmetic method for depositing an anti-dandruff agent on the scalp, comprising the step of applying a hair care composition of any embodiment of the first aspect of the present invention to the surface of the scalp of an individual. This method is for non-therapeutic benefits. [Modes for carrying out the invention]

[0009] The term "hair care composition" refers to a composition for topical application to the hair and / or scalp of mammals, particularly humans. Such compositions can generally be classified as leave-on or rinse-off. The compositions of the present invention may be in the form of a liquid, lotion, cream, foam, scrub, gel, or bar. Non-limiting examples of such compositions include leave-on hair lotions and creams, and rinse-off shampoos, conditioners, shower gels, or toilet bars. The compositions of the present invention are preferably rinse-off compositions, particularly preferably shampoos or conditioners, and most preferably shampoos.

[0010] The cation charge density refers to the number of cation charges per unit weight of a given polymer. As used herein, the term “charge density” refers to the ratio of the positive charge on 20 monomer units containing the polymer to the molecular weight of said monomer units. Multiplying the charge density by the polymer molecular weight determines the number of positively charged sites on a given polymer chain. The cation charge density can be calculated from the degree of substitution described in International Publication No. 2013 / 011122, the entire disclosure, particularly pages 8-17, is incorporated herein by reference.

[0011] The cation charge density of a polymer can also be appropriately determined under chemical testing for nitrogen determination by the Kjeldahl method, as described in the United States Pharmacopeia, and is expressed in milliequivalents per gram (meq).

[0012] The cation charge density is measured at pH 7.

[0013] Water insolubility refers to a material whose solubility in water at 25°C and atmospheric pressure is 0.1% by weight or less.

[0014] Molecular weight refers to the weight average molecular weight of a given polymer. The weight average molecular weight (WAVG MW) of a given polymer is determined by SEC (size exclusion chromatography) analysis using absolute calibration (universal calibration). Polysaccharide standards pullulan and dextran were used for calibration.

[0015] Unless otherwise indicated by way of example or explicitly stated otherwise, all numbers in this specification indicating amounts of materials or conditions of reactions, physical properties of materials, and / or uses may be understood to be modified by the term "about".

[0016] All amounts are by weight of the final hair care composition unless otherwise specified.

[0017] Note that when specifying any range of values, any particular upper value can be associated with any particular lower value.

[0018] When features are disclosed with respect to particular aspects of the invention (e.g., compositions of the invention), such disclosure should be considered to apply, with the necessary modifications, to any other aspect of the invention (e.g., methods of the invention).

[0019] Polymers suitable for use in the compositions of the invention include acrylamidopropyltrimonium chloride. Preferably, the copolymer also includes acrylamide in addition to acrylamidopropyltrimonium chloride. A particularly preferred copolymer is a copolymer of acrylamidopropyltrimonium chloride and acrylamide.

[0020] The polymers and / or copolymers according to the invention have a charge density of at least 3.5 meq / g, more preferably 4 meq / g or more, and most preferably 4.3 - 5.3 meq / g at pH 7.

[0021] The homopolymers and / or copolymers preferably have a weight average molecular weight of 100,000 - 500,000, more preferably 150,000 - 400,000.

[0022] A suitable homopolymer example is commercially available from Ashland under the trade name N-DurHance A-1000 (registered trademark) (a cationic homopolymer of acrylamidopropyltrimethylammonium chloride). A suitable copolymer example is commercially available from Ashland under the trade name N-DurHance AA2000 (registered trademark) (a cationic copolymer of acrylamidopropyltrimonium chloride / acrylamide copolymer).

[0023] Typically, the cationic polymer is present in an amount of 0.01 to 5% by weight, preferably 0.05 to 2% by weight, and more preferably 0.1 to 1% by weight of the total composition.

[0024] In addition to homopolymers / copolymers, additional cationic deposition polymers may be included, but these are undesirable.

[0025] A preferred form of the composition is an anti-dandruff shampoo. The anti-dandruff shampoo may appropriately contain 50-90%, preferably 60-80% by weight, of water in the total shampoo.

[0026] Cleansing phase The cleansing phase comprises one or more cleansing surfactants. Cleansing surfactants are those that act to cleanse the hair and / or scalp. The total amount of cleansing surfactants is preferably 3-45%, more preferably 5-25%, and most preferably 7-20% by weight of the total composition.

[0027] Preferably, the cleansing surfactant includes an anionic surfactant. The anionic surfactant includes ethoxylated alkyl sulfate anionic surfactants.

[0028] The preferred alkyl ether sulfate is of formula (I), RO-(CH2CH2-O) n -SO3 - M + (I) In the formula, R is a linear or branched alkyl chain having 8 to 18 (preferably 12 to 18) carbon atoms; n is the average degree of ethoxylation, ranging from 0.5 to 3 (preferably 1 to 3); and M is a solubilizing cation such as sodium, potassium, ammonium, or substituted ammonium. One example is sodium lauryl ether sulfate (SLES). The most preferred example is SLES having an average degree of ethoxylation of 0.5 to 3, preferably 1 to 3.

[0029] A preferred amount of such surfactant is 2 to 20% by weight of the total composition, more preferably 7 to 15% by weight.

[0030] Other surfactants, such as alkyl sulfates, may be present in the composition. Preferred alkyl sulfates are C 8-18 Alkyl sulfates, more preferably C 12-18 These are alkyl sulfates, preferably in the form of salts with solubilizing cations such as sodium, potassium, ammonium, or substituted ammonium. Examples include sodium lauryl sulfate (SLS) or sodium dodecyl sulfate (SDS).

[0031] The cleansing phase may contain one or more further anionic surfactants that are cosmetically acceptable and suitable for topical application to hair and / or scalp. Examples of further anionic surfactants include alkyl sulfonates, alkyl succinates, alkyl sulfosuccinates, alkyl ether sulfosuccinates, N-alkyl sarcosinates, alkyl phosphates, alkyl ether phosphates, and alkyl ether carboxylic acids and their salts, particularly their sodium, magnesium, ammonium, and mono-, di-, and triethanolamine salts. Alkyl ether sulfosuccinates, alkyl ether phosphates, and alkyl ether carboxylic acids and their salts may contain 1 to 20 ethylene oxide or propylene oxide units per molecule.

[0032] Typical anionic cleansing surfactants for use in the shampoo composition according to the present invention include sodium oleylsuccinate, ammonium lauryl sulfosuccinate, sodium lauryl ether sulfosuccinate, sodium dodecylbenzenesulfonate, triethanolamine dodecylbenzenesulfonate, lauryl ether carboxylic acid and sodium N-lauryl sarcosinate, sodium lauryl monoglyceride sulfate, sodium lauryl sulfate, sodium laureth sulfate, sodium cosyl sulfate, sodium cocoyl isethionate, and mixtures thereof.

[0033] The composition may contain co-surfactants to help impart aesthetic, physical, or cleaning properties to the composition. Co-surfactants are preferably included in the cleansing phase of the composition. Examples of co-surfactants are nonionic surfactants, which may be included in amounts ranging from 0.5 to 10%, preferably 2 to 8%, and more preferably 1 to 5% by weight of the total composition.

[0034] For example, typical nonionic surfactants that can be included in a treatment composition, preferably the shampoo composition of the present invention, include aliphatic (C8-C) surfactants. 18 These include condensation products of primary or secondary linear or branched alcohols or phenols with alkylene oxides, usually ethylene oxide, and generally have 6 to 30 ethylene oxide groups. Other representative nonionic surfactants include mono- or di-alkylalkanolamides. Examples include coco-mono- or di-ethanolamides and coco-mono-isopropanolamides.

[0035] Further nonionic surfactants that may be included are alkyl polyglycosides (APGs). Typically, APGs contain alkyl groups bonded (may be via crosslinking groups) to a block of one or more glycosyl groups. Preferred APGs are defined by the following formula (II): R ’ O-(G) k (II) In the formula, R’ is a branched or straight-chain alkyl group which may be saturated or unsaturated, and G is a sugar group. R ’ represents an average alkyl chain length of about C5 to about C 20 and may represent an average alkyl chain length of about C8 to about C 12 Most preferably, the value of R' is about 9.5 to about 10.5. G may be selected from C5 or C6 monosaccharide residues and is preferably a glucoside. G may be selected from the group including glucose, xylose, lactose, fructose, mannose and their derivatives. Preferably, G is glucose. The degree of polymerization k may have a value of about 1 to about 10 or more, preferably the value of k is about 1.1 to about 2, and most preferably the value of m is about 1.3 to about 1.5. Alkyl polyglycosides suitable for use in the present invention are commercially available, and examples include materials specified as Oramix NS10 of Seppic, Plantaren 1200 and Plantaren 2000 of Henkel.

[0036] Other sugar-derived nonionic surfactants that can be included in the compositions (preferably shampoos) of the present invention include C 10 -C 18 N-alkyl (C1-C6) polyhydroxy fatty acid amides, such as C 12 -C 18 N-methylglucamide, and N-alkoxy polyhydroxy fatty acid amides, such as C 10 -C 18 N-(3-methoxypropyl) glucamide.

[0037] Preferred examples of the co-surfactant are amphoteric or zwitterionic surfactants and may be included in amounts in the range of 0.5 to about 10% by weight, preferably 2 to 8, more preferably 1 to 5% by weight of the total composition.

[0038] Examples of amphoteric or zwitterionic surfactants include alkylamine oxide, alkyl betaine, alkylamidopropyl betaine, alkyl sulfobetaine (sultaine), alkyl glycinate, alkyl carboxyglycinate, alkyl amphoacetate, alkyl amphopropionate, alkyl amphoglycinate, alkylamidopropyl hydroxysultaine, acyl taurate, and acyl glutamate, where the alkyl and acyl groups have 8 to 22 carbon atoms. Typical amphoteric and zwitterionic surfactants for use in the shampoo of the present invention include laurylamine oxide, cocodimethylsulfopropyl betaine, lauryl betaine, cocamidopropyl betaine, and sodium cocoamphoacetate.

[0039] Particularly preferred amphoteric or zwitterionic surfactants are amidobetaine amphoteric surfactants of general formula (III), [ka] In the formula, m is 2 or 3, and R 1 C(O) is selected from linear or branched, saturated or unsaturated acyl groups having 8 to 22 carbon atoms and mixtures thereof, R 2 and R 3 Each of these is independently selected from alkyl, hydroxyalkyl, or carboxyalkyl groups having 1 to 6 carbon atoms and mixtures thereof. One example is cocamidopropyl betaine. A preferred amount of such surfactant is 0.5 to 10% by weight, more preferably 2 to 8% by weight, and most preferably 1 to 5% by weight of the whole composition.

[0040] Optional but preferred further surfactants are alkylglycinates and / or alkylcarboxyglycinates. If present, they are present in an amount of 1-8% by weight, preferably 2-6% by weight.

[0041] Preferably, alkylglycinates and / or alkylcarboxyglycinates are in the form of salts with solubilizing cations such as sodium, potassium, ammonium, or substituted ammonium, C 8-22 It has an alkyl group of 1 carbon atom. Preferred glycinates are sodium cocoglycinate and sodium cocoylglycinate.

[0042] A mixture of any of the aforementioned amphoteric or zwitterionic surfactants may also be suitable. A preferred mixture is a mixture of cocamidopropyl betaine and one of the further amphoteric or zwitterionic surfactants described above. A preferred further amphoteric or zwitterionic surfactant is sodium cocoamphoacetate.

[0043] In preferred embodiments, the cleansing phase comprises an alkyl sulfate and / or ethoxylated alkyl sulfate anionic surfactant and a betaine surfactant, preferably alkylamidopropyl betaine.

[0044] The total amount of surfactants (including co-surfactants) in a hair treatment composition is generally 1 to 50% by weight of the total composition, preferably 2 to 40% by weight, and more preferably 10 to 25% by weight.

[0045] Piroctone compounds The piroctone compounds used in the present invention may include piroctonic acid, primary, secondary, and tertiary olamine salts of piroctonic acid (such as diethanolamine and triethanolamine salts), and mixtures thereof, preferably piroctonic acid, primary olamine salts of piroctonic acid (i.e., piroctone olamine, also known as Octopirox®), and mixtures thereof.

[0046] Piroctone compounds useful in the present invention typically include a structure defined by formula (IV), [ka] In the formula, R4 is selected from C1-C17 hydrocarbon groups, R5 is selected from C1-4 alkyl, C2-4 alkenyl or alkynyl, hydrogen, phenyl or benzyl, and M1 is selected from hydrogen, monoethanolamine (MEA), diethanolamine (DEA) or triethanolamine (TEA). A preferred R4 group is (CH3)3CCH2CH(CH3)CH2- and a preferred R5 is methyl. More preferably, R4 is (CH3)3CCH2CH(CH3)CH2-, R5 is methyl, and M1 is hydrogen or MEA. Most preferably, R4 is (CH3)3CCH2CH(CH3)CH2-, R5 is methyl, and M1 is hydrogen.

[0047] Piroctone olamine is particularly preferred.

[0048] The typical amount of the piroctone compound is 0.01 to 5% by weight of the total composition, preferably 0.05 to 2% by weight, and more preferably 0.1 to 1.5% by weight.

[0049] Preferably, the weight ratio of homopolymer / copolymer to piroctone compound is preferably 2:1 or more preferably 1.5:1 or less, and most preferably 0.3:1 to 1.1:1.

[0050] Preferably, the piroctone compound constitutes at least 50% by weight, more preferably at least 70% by weight, of the total amount of the anti-dandruff agent in the composition.

[0051] Oil-in-water emulsion The composition according to the present invention may include an oil-in-water emulsion.

[0052] The aqueous phase of the emulsion contains water. Ideally, the emulsion contains 25-85%, preferably 40-70%, and more preferably 45-60% by weight of water.

[0053] Silicones are present in oil-in-water emulsions. Silicones are conditioning agents intended to deposit on hair that remains after rinsing with water.

[0054] Silicone in water-in-oil emulsion (D 3,2 The droplet size is preferably 10 nm to 10 microns, more preferably 50 nm to 5 microns, and most preferably 100 nm to 5 microns. 3,2 It has an average droplet diameter. D 3,2 The average droplet diameter can be measured using laser light scattering techniques, for example, with a Malvern Instruments 2600D Particle Sizer.

[0055] The typical amount of silicone is 0.1 to 5% by weight of the total composition, preferably 0.3 to 3% by weight, and more preferably 0.5 to 2.5% by weight.

[0056] Typical silicones include polyalkylsiloxanes, polyarylsiloxanes, polyalkylarylsiloxanes, polyethersiloxane copolymers, and mixtures thereof.

[0057] Silicones may include functionalized silicones. Suitable functionalized silicones include, for example, hydroxyl-, amino-, carboxy-, betaine-, quaternary ammonium-, carbohydrate-, hydroxy-, and alkoxy-substituted silicones. Functionalized silicones may also contain multiple substitutions. Preferably, the functionalized silicone is an aminosilicone, in particular when a priloctone compound is solubilized in the silicone.

[0058] The aminosilicone described in European Patent No. 455185 comprises trimethylsilylamodimethicone as shown below and is sufficiently water-insoluble for use in emulsions. Si(CH3)3-O-[Si(CH3)2-O-]x-[Si(CH3)(R6-NH-CH2CH2-NH2)-O-]y-Si(CH3)3 In the formula, x+y is a number from approximately 50 to approximately 500, the weight percentage of the amine functional group is from approximately 0.03% to approximately 8%, and R6 is an alkylene group having 2 to 5 carbon atoms. Preferably, the number x+y is from 100 to 300, and the weight percentage of the amine functional group is from approximately 0.5% to 4%. As expressed herein, the weight percentage of the amine functional group is measured by titrating a sample of aminosilicone with alcoholic hydrochloric acid to the bromocresol green endpoint. The weight percentage of the amine is calculated using a molecular weight of 45 (corresponding to CH3-CH2-NH2).

[0059] Other cationic polymers include polygalactomannan and polysaccharide polymers, such as cationic cellulose derivatives and cationic starch derivatives.

[0060] Suspensioning agent The suspending agent is a desirable feature of the composition. Suitable suspending agents are selected from polyacrylic acid, crosslinked polymers of acrylic acid, copolymers of acrylic acid and hydrophobic monomers, copolymers of carboxylic acid-containing monomers and acrylic acid esters, crosslinked copolymers of acrylic acid and acrylate esters, heteropolysaccharide gums, and crystalline long-chain acyl derivatives. The long-chain acyl derivatives are preferably selected from ethylene glycol stearate, fatty acid alkanolamides having 16 to 22 carbon atoms, and mixtures thereof. Ethylene glycol distearate and polyethylene glycol 3-distearate are preferred long-chain acyl derivatives because they impart a pearly luster to the composition. Polyacrylic acid is commercially available as Carbopol 420, Carbopol 488, or Carbopol 493. Polymers of acrylic acid crosslinked with polyfunctional agents may also be used. These are commercially available as Carbopol 910, Carbopol 934, Carbopol 941, and Carbopol 980. A suitable copolymer of carboxylic acid-containing monomers and acrylate esters is Carbopol 1342. All Carbopol® materials are available from Goodrich. Suitable crosslinking polymers of acrylic acid and acrylate esters are Pemuren TR1 or Pemuren TR2. Suitable heteropolysaccharide gums are xanthan gums, available as e.g., Kelzan mu.

[0061] A mixture of any of the above suspending agents may be used. A mixture of acrylic acid and a crosslinked polymer of a crystalline long-chain acyl derivative is preferred.

[0062] The most preferred example is a cross-linked polyacrylate polymer.

[0063] If present, the suspending agent is generally found in the shampoo composition of the present invention in an amount of 0.01 to 5% by weight, preferably 0.1 to 2.5% by weight, and more preferably 0.25 to 1% by weight.

[0064] The viscosity of the composition, when measured at 30°C using a Brookfield V2 viscometer (spindle RTV5, 1 min, 20 rpm), is preferably in the range of 3,000 to 10,000 mPa.s, more preferably 4,000 to 8,000 mPa.s, and more preferably 5,000 to 7,000 mPa.s.

[0065] The pH of the composition of the present invention is preferably in the range of 3 to 9, more preferably 4 to 7, and even more preferably 4.5 to 6.5.

[0066] Other optional components The composition may optionally contain one or more components for use in hair treatment products, provided that the optional components are physically and chemically compatible with the essential components described above herein and otherwise do not excessively impair the feel, rheology, and conditioning performance of the formulation. The individual concentrations of such optional components may range from 0.001% to 10% by weight, preferably 0.01% to 5% by weight, of the whole composition. Such components may include fragrances, dyes and pigments, pH adjusters, pearlescent or opaque agents, viscosity modifiers, preservatives, and natural hair nutrients such as plant and fruit extracts, sugar derivatives, and amino acids. The composition may also contain additional silicones not present in the oil-in-water emulsion phase. The additional silicones may be the same as or different from the silicones present in the emulsion phase. The composition may also contain further anti-dandruff and / or antimicrobial agents such as pyridinethione salts, pine tar, sulfur, salicylic acid, azole, selenium sulfide, or mixtures thereof.

[0067] How to use The composition is used in a method of treating a surface. An effective amount of the composition is applied to a desired surface, preferably selected from hair and / or scalp, which is wet with water. The composition can remain on the surface for a given time, preferably in combination with massage, to exert its effect before being rinsed off with water. The given time is preferably 20 seconds to 2 minutes, more preferably 30 seconds to 1 minute. The effective amount is typically in the range of 1 g to 20 g, preferably 2.5 g to 10 g.

[0068] The compositions of the present invention are primarily intended to be either rinse-off or leave-on compositions, preferably rinse-off compositions such as shampoos, and are intended for topical application to at least a portion of the scalp and / or hair of an individual.

[0069] The following examples are provided to facilitate understanding of the present invention. The examples are not provided to limit the scope of the claims. Examples of the present invention are indicated by numbers, and comparative examples by letters.

[0070] [Examples] The following examples were prepared.

[0071] [Table 1]

[0072] 0.1 g of the example composition / g of hair was uniformly applied to a hairpiece. The hairpiece was washed twice. After washing, the hairpiece was placed in a drying cabinet (50°C) until dry. After drying, the hairpiece was transferred to a bottle containing 10 ml of ethanol. The bottle was sealed and placed on a bottle roller for a known time. Using the HPLC-UV methodology, samples of appropriate size for analysis were taken from the bottle using a syringe and filtered into a vial for analysis against a known set of standards containing a known amount of Octopirox (μg / ml) in ethanol.

[0073] [Table 2]

[0074] The embodiments of the present invention deposit octopirox into hair more effectively than the comparative examples.

Claims

1. a) Piroctonic acid, primary, secondary and tertiary olamine salts of piroctonic acid, and a compound represented by the following formula (IV): 【Chemical 1】 (In the formula, R ４ is C １ -C １７ R is selected from hydrocarbon groups; ５ is C1-4 alkyl, C ２－４ selected from alkenyl or alkynyl, hydrogen, phenyl or benzyl; M １ is selected from hydrogen, monoethanolamine (MEA), diethanolamine (DEA) or triethanolamine (TEA). a piroctone compound selected from the group of compounds comprising compounds comprising a structure defined by b) cationic homopolymers and / or copolymers comprising acrylamidopropyltrimonium moieties, said homopolymers and / or copolymers having a charge density of at least 3.5 meq / g at pH 7 and a weight average molecular weight (g / mol) of 100,000 to 500,000; A hair care composition comprising: The hair care composition further comprises an anionic surfactant.

2. 10. The hair care composition of claim 1, wherein the weight ratio of homopolymer / copolymer to piroctone compound is 2:1 or less.

3. 3. The hair care composition of claim 1, wherein the piroctone compound is piroctone olamine.

4. 4. A hair care composition according to any one of claims 1 to 3, wherein the copolymer is an acrylamidopropyltrimonium chloride / acrylamide copolymer.

5. 5. The hair care composition of claim 4, wherein the weight ratio of acrylamidopropyltrimonium chloride to acrylamide in said copolymer is greater than 2:

1.

6. 6. A hair care composition according to any one of claims 1 to 5, wherein the amount of the cationic polymer is from 0.001 to 2% by weight of the total composition.

7. The hair care composition of claim 1 , wherein the composition is a shampoo.

8. 8. A hair care composition according to any one of claims 1 to 7, wherein the piroctone compound is present in an amount of 0.01 to 5% by weight of the total composition.

9. A hair care composition according to any preceding claim, wherein the cationic polymer is present in an amount of from 0.01 to 5% by weight of the total composition.

10. 10. The hair care composition of claim 1, further comprising a silicone emulsion.

11. 11. The hair care composition of claim 1, wherein the piroctone compound is piroctone olamine.

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