WO2000018863A1 - Polymer compounds and compositions comprising them - Google Patents

Abstract

A water-soluble or water-dispersible compound is provided. The compound is the reaction product of: (i) an at least sparingly water soluble polymer having an extinction coefficient of less than 2000 1 mol-1 cm-1 at wavelengths in the range 220-300 nm with (ii) at least one sunscreen molecule and/or singlet oxygen quencher molecule. Compositions comprising the compounds, and, a method of reducing the photofading of substrates by the use of the compounds or compositions are also provided.

Description

POLYMER COMPOUNDS AND COMPOSITIONS COMPRISING THEM

Technical Field

The present invention relates to a compound which is a polymer substituted with at least one sunscreen or singlet oxygen quencher (SOQ) in particular to such a compound comprising a polymer which prior to substitution exhibits little or no UV radiation absorption at wavelengths in the range 220-300 nm.

Background of the Invention

Polymeric compounds are known to act as aids for the deposition of benefit agents to substrates such as fabrics. Polymeric deposition aids are, for example, known as delivery vehicles in fabric treatment compositions (typically fabric washing and rinsing compositions) for depositing benefit agents, such as anti-dye transfer agents and fabric conditioning agents, onto fabrics.

Polymeric deposition aids have also been used to deposit active compounds, such as sunscreens, onto a substrate. The harmful effects of UV radiation, especially solar UV radiation, upon skin are well documented as are the detrimental effects upon the colour longevity of a substrate e.g. fabric exposed to UV radiation. In the latter photofading of the substrate occurs. Typically this occurs as photofading of a dye applied to, or incorporated in, the substrate.

However, known polymeric deposition aids may unfortunately increase the tendency for photofading of the substrate to occur (e.g. when the substrate is dried by exposure to sunlight, or, during exposure by wearing of a fabric). This reduces the benefit obtained by the use of the benefit agents or introduces an undesirable side effect from the use of the deposition aid. This increased photofading can also lead to loss of fabric integrity or strength and a less attractive appearance over a period of time. This can occur even when an anti-photofading benefit agent is deposited by the polymeric deposition aid.

US 5,243,021 (Langer et al) discloses water-dispersible or water-soluble co-polymers which contain active compounds i.e. at least one UVA radiation absorbing monomer (sunscreen), one UVB radiation absorbing monomer (sunscreen), and also one hydrophilic monomer and optionally, one hydrophobic monomer component as a deposition aid. The products of Langer are obtained by reacting together the aforementioned monomers to produce a block co-polymer product containing sunscreen monomers.

The effectiveness of such known co-polymers in delivering active compounds, such as sunscreens, to a substrate is adequate during the laundry process, especially upon a cotton substance. However, on exposure to UV radiation a detrimental effect on the colour longevity of the substrate may result.

Thus according to the known art whilst a broad-spectrum sunscreen is effectively delivered to a substrate there is frequently a concurrent detrimental effect upon the colour longevity of the substrate, such as a coloured fabric garment, upon exposure to UV radiation.

US-A-5 217 806 discloses UV-stabilised formed structures from aromatic polyether ketones. The object is to safeguard structures formed from aromatic polyether ketones from ultraviolet light damage. The structures include filaments and fibres, knitted, woven or non-woven structures. The treatment consists of applying a polymer film comprising an ultraviolet stabiliser dissolved or dispersed therein. The film is described as capable of absorbing ultraviolet radiation. The film-forming polymer is a polyaryl sulfone or copolymer thereof. The present invention is distinguished from this disclosure in that there is no bond between the UV absorber and the water-soluble polymer. Further, there is no disclosure at all of applying any such material as a sunscreen in a fabric laundering or a fabric care process. US-A-3 749 699 discloses a light-sensitive film forming polymer. The backbone may optionally be polyvinylalcohol onto which light-sensitive components are grafted. However, all of the examples require the product to be dissolved in organic solvents and they can be precipitated using water. Therefore, these materials are not in fact water-soluble. Further, there is, however, no disclosure at all of using these compounds to deposit sunscreen in a method of fabric washing or fabric care and they are not at all suitable for that purpose.

The present invention is directed towards overcoming the disadvantages associated with the above technical problems, and in particular, to overcoming the technical problem of increasing the resistance of a substrate to photofading whilst providing good deposition of the relevant benefit agent.

The references herein to "photofading" include the yellowing of white substrate, especially a fabric, such as cotton, due to the action of UV radiation. The term "coloured" substrates therefore includes a white substrate which is prone to yellowing in this manner.

Statement of Invention

A soluble or water-dispersible compound which is the reaction product of: (i) an at least sparingly water soluble polymer having an extinction coefficient of less than 2000 1 mol^"1 cm^"1 at wavelengths in the range 220-300 nm, with (ii) at least one sunscreen molecule and/or singlet oxygen quencher molecule.

The invention further provides a composition comprising at least one active ingredient and a compound of the present invention. Furthermore, the present invention provides a method of reducing photo fading by UV radiation of a substrate and/or increasing the sun protection factor of a substrate by treatment with a compound or composition of the present invention.

The compounds and compositions of the present invention provide the advantages of effective deposition onto a substrate, particularly a fabric such as cotton, combined with effective reduction of photofading of the substrate caused by exposure to UV radiation. Typically an increase in the sun protection factor (SPF) of the substrate is also provided.

It has been found that prior art sunscreen containing compounds, eg those of Langer et al, which use monomers having a high extinction co-efficient in the range 220-300 nm do not provide the advantages of the present invention. The monomers of Langer have high extinction co-efficients in the wavelength range 200-250 nm eg 3600 1 mol^" cm^" .

Detailed Description of the Invention

The compounds of the invention are water soluble or water dispersible. As used herein the reference to "water-soluble compounds" refers to compounds which have a solubility in water at 20°C of at least 1 g/1, preferably at least 5 g/1.

By water-dispersible what is meant is a compound having at least a k/s (function of reflectance) of 0.2 on cotton at lambda of absorption from a mixture of water plus polymer (polymer present at an activity of 10^" moles litre^" ).

The compounds usually have the polymer forming a 'backbone' thereof. By 'backbone' what is meant is the part of the compound that consists of a chain of monomer units used to make up the polymer upon which the sunscreen and/or SOQ groups can be attached, typically, in a pendant or terminal position. The compounds of the present invention, i e the above polymer substituted with at least one sunscreen molecule or SOQ molecule, have an extinction co-efficient of greater than 2000 1 mol^"1 cm^"1 at the wavelength of maximal absorption in the wavelength range 275-380 nm, preferably greater than 3000 1 mol^" cm^" , more preferably greater than 5000 1 mol^" cm^" eg greater than 10,000 1 mol^" cm^"

References herein to sunscreens and/or SOQs refers to the sunscreen or SOQ molecules used to produce the compound and those molecules after substitution onto the polymer More than one type of sunscreen/SOQ molecule can be used

Typically compounds comprising sunscreen molecules have higher extinction coefficients than compounds comprising SOQ molecules The extinction co-efficient refers to the highest absorption of a 1 molar solution at any wavelength in a 1 cm cell at 20°C When the polymer is substituted with a sunscreen and/or SOQ the extinction co- efficient measured is that of the substituted polymer i e as the compound Otherwise the extinction co-efficient refers to the polymer before substitution

The compounds of the invention may be described as "polymer/sunscreen and/or SOQ complexes" as the polymer and the sunscreen and/or SOQ are reacted together to form the compound Other components may also be reacted with the polymer in addition to the essential sunscreen and SOQ

The polymer and the sunscreen and/or SOQ may be attached directly to each other, i e reacted directly together so as to be chemically linked without an 'interrupting' group present between the polymer and sunscreen and/or SOQ Alternatively, the polymer and sunscreen and/or SOQ attachment may be interrupted or substituted by one or more interrupting groups that do not have sunscreen or SOQ properties Suitable interrupting groups include S-triazine, β-sulphone, alkyl groups and ethylene oxide residues

The sunscreen and/or SOQs may be attached in a pendent position on the polymer and/or may be present in the polymer 'backbone' i e in an arrangement as found in a random or block copolymer. In the latter, more unusual arrangement, a compound of the invention having a terminal sunscreen and/or SOQ would be further reacted with a suitable polymer to result in the arrangement.

References herein to a polymer includes suitable co-polymers and homopolymers provided that the present specified extinction co-efficient values are met.

The compounds of the present invention are formed from the unsubstituted polymer having an extinction co-efficient of less than 2000 1 mol ^" cm ^" at wavelengths in the range 220 to 300 nm. The unsubstituted polymers have the extinction co-efficient of less than 2000 1 mol-1 cm-1 at all wavelengths in the range 220 to 300 nm. Preferably the unsubstituted polymer has an extinction co-efficient of less than 1000 1 mol^" cm^" , most preferably less than 500 1 mol^" cm^" , e.g. less than 100 mol^' cm^" . The extinction co-efficient is measured by a 1 molar solution of the polymer in a 1 cm curvette.

The polymer used according to the invention is at least sparingly water-soluble at 20°C. Any at least sparingly water-soluble polymer, as herein defined, may be used according to the present invention. Preferably the polymer has a water-solubility at 20°C of at least 0.00001 moles/litre, preferably at least 0.001 moles/litre, more preferably at least 0.005 moles/litre, e.g. at least 0.05 moles/litre prior to substitution with the sunscreen or SOQ.

The polymer used typically has a molecular weight in the range 1,000 - 200,000 g/mol, preferably 2,000 - 280,000 g/mol more preferably 10,000 - 25,000 g/mol.

It is especially preferred if the polymers have a low polydispersability, with preferably, more than 80%, especially more than 95% of the sample eluted within 90-110% of the mean average molecular mass. Therefore, the polymers preferably have a high non- dispersibility. The polymers which may be used to produce the claimed compounds are those defined by the claimed extinction co-efficient (prior to substitution), which are suitable chemical species for depositing onto a substrate and which are reactive with the sunscreen and/or SOQ Suitable polymers have multiple sites for substrate recognition and no, or little, character carbon in the structure PVA satisfies this requirement fully whilst examples of SCMC have good surface recognition but include a low, but acceptable, percentage of sp2 hydridised carbon

Particular polymers which may be used include, amongst others, poly vinyl alcohol (PVA), sodium carboxymethyl celluloses ( e g SCMC), polysaccharides and other carbohydrates, natural and synthetic gums (such as guar gum etc ), cellubioses polyalkylene glycols (e g polyethylene glycols) pyrollidones, (meth)acylates and (meth)acrylamides and polyacids In particular PVA and SCMC polymers are suitable

The sunscreens and/or SOQs typically occupy 0 1-15% by moles of the available substitution sites on the polymer, this is referred to herein as the degree of substitution Preferably the degree of substitution is 0 2% to 10% by moles, more preferably 0 4% to 8%> by moles

Any sunscreens or SOQs as hereindefined may be used according to the present invention More than one type of sunscreen or SOQ may be present in the compounds Accordingly compounds comprising at least one sunscreen and at least one SOQ are within the scope of the present invention

The term "sunscreen" as used herein refers to a molecule with an extinction co-efficient greater than 2000 1 mol^" cm^" at a wavelength of maximal absorption Typically for a sunscreen maximal absorption occurs at wavelengths of 290-370 nm, more usually 310- 350 nm, especially 330-350 nm Any suitable 'sunscreen' may be used according to the present invention Examples of suitable sunscreens are given in Cosmetic Science and Technology Series, Vol. 15; Sunscreens; 2nd edition; edited by Lowe, Shoath and Pathak; Cosmetics and Toiletries; Vol. 102; March 1987; pages 21-39; and Evolution of Modern Sunscreen Chemicals; pages 3-35 both by N.A. Saarth.

In particular, suitable sunscreens include carboxylic acids or carboxylic acid derivatives, for example acrylates, cinnamates and benzoates or derivatives thereof, such as 4-methoxy cinnamate salicylates, PABA, 4-acetoxy benzoate dibenzoylmethanes, phenyl benzoimidazoles, aminobenzoates, benzotriazoles and benzophenones.

The term "singlet oxygen quencher" (SOQ) as used herein refers to compounds having a rate constant of greater than 1 x 10 1 mol ^" s^" with O₂, preferably a rate constant greater than 1 x 10 mol^" s^" . The rate constant is measured by the method as defined by Wilkinson et al in "Journal of Physical and Chemical" reference Data 1995, Vol. 24, No. 2, page 668. The rate constant of the singlet oxygen quencher is measured by using the phosphorescence at 1270 nm as a function of quencher concentration. The correlation between quencher concentration and lifetime of the singlet oxygen gives the quenching constant for that quencher.

Suitable SOQs include, amongst others, benzofurans, coumeric acids or derivatives thereof, for example 2-carboxy benzofuran and bis(p-amine sulphonates) triazine, DABCO derivatives, tocopherol derivatives, tertiary amines and aromatic substituted alcohols eg BHT.

The polymer and the sunscreen and/or SOQ may be joined in a linear arrangement with the sunscreen and/or SOQ forming part of the polymer backbone. Alternatively, and preferably, the sunscreen and/or SOQ may be a pendant or terminal group on the polymer 'backbone'. A mixture of the two arrangements is also possible. The compound of the present invention may be incorporated into compositions comprising an active ingredient. The compound is typically included in said compositions at levels of from 0.005% to 5% by weight, preferably 0.01% to 2%, most preferably 0.025% to 1%.

The active ingredient in the compositions is preferably a surface active agent or a fabric conditioning agent. More than one active ingredient may be included. For some applications a mixture of active ingredients may be used.

The compositions of the invention may be in any physical form e.g. a solid such as a powder or granules, a solid bar, a paste, gel or liquid, especially, an aqueous based liquid. In particular the compositions may be used in laundry compositions, especially in liquid or powder laundry composition.

The compositions of the present invention are preferably laundry compositions, especially main wash (fabric washing) compositions or rinse-added softening compositions. The main wash compositions may include a fabric softening agent and rinse-added fabric softening compositions may include surface-active compounds, particularly non-ionic surface-active compounds, if appropriate.

The detergent compositions of the invention may contain a surface-active compound (surfactant) which may be chosen from soap and non-soap anionic, cationic, non-ionic, amphoteric and zwitterionic surface-active compounds and mixtures thereof. Many suitable surface-active compounds are available and are fully described in the literature, for example, in "Surface- Active Agents and Detergents", Volumes I and II, by Schwartz, Perry and Berch.

The preferred detergent-active compounds that can be used are soaps and synthetic non-soap anionic and non-ionic compounds. The compositions of the invention may contain linear alkylbenzene sulphonate, particularly linear alkylbenzene sulphonates having an alkyl chain length of C₈-C₁₅ It is preferred if the level of linear alkylbenzene sulphonate is from 0 wt% to 30 wt%, more preferably 1 wt% to 25 wt%, most preferably from 2 wt% to 15 wt%

The compositions of the invention may contain other anionic surfactants in amounts additional to the percentages quoted above Suitable anionic surfactants are well-known to those skilled in the art Examples include primary and secondary alkyl sulphates, particularly C₈-C₁₅ primary alkyl sulphates, alkyl ether sulphates, olefin sulphonates, alkyl xylene sulphonates, dialkyl sulphosuccinates, and fatty acid ester sulphonates Sodium salts are generally preferred

The compositions of the invention may also contain non-ionic surfactant Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, especially the c_s-c₂₍₎ aliphatic alcohols ethoxylated with an average of from 1 to 20 moles of ethylene oxide per mole of alcohol, and more especially the C₁₀-C₁₅ primary and secondary aliphatic alcohols ethoxylated with an average of from 1 to 10 moles of ethylene oxide per mole of alcohol Non-ethoxylated nonionic surfactants include alkylpolyglycosides, glycerol monoethers, and polyhydroxyamides (glucamide)

It is preferred if the level of non-ionic surfactant is from 0 wt% to 30 wt%, preferably from 1 wt% to 25 wt%, most preferably from 2 wt% to 15 wt%

The choice of surface-active compound (surfactant), and the amount present, will depend on the intended use of the detergent composition In fabric washing compositions, different surfactant systems may be chosen, as is well known to the skilled formulator, for handwashing products and for products intended for use in different types of washing machine

The total amount of surfactant present will also depend on the intended end use and may be as high as 60 wt%, for example, in a composition for washing fabrics by hand In compositions for machine washing of fabrics, an amount of from 5 to 40 wt% is generally appropriate Typically the compositions will comprise at least 2 wt% surfactant e g 2-60%, preferably 15-40% most preferably 5-35%

Detergent compositions suitable for use in most automatic fabric washing machines generally contain anionic non-soap surfactant, or non-ionic surfactant, or combinations of the two in any suitable ratio, optionally together with soap

Any conventional fabric conditioning compound may be used in the compositions of the present invention The conditioning compounds may be cationic or non-ionic If the fabric conditioning compound is to be employed in a main wash detergent composition the compound will typically be non-ionic The term fabric conditioning compound as used herein includes fabric softening compounds or agents

The fabric conditioning compound is suitably a substantially water insoluble quaternary ammonium material comprising a single alkyl or alkenyl long chain having an average chain length greater than or equal to C₂₀ or, more preferably, a compound comprising a polar head group and two alkyl or alkenyl chains having an average chain length greater than or equal to C₁₄

Preferably the fabric conditioning compound has two long chain alkyl or alkenyl chains each having an average chain length greater than or equal to C₁₆ Most preferably at least 50%> of the long chain alkyl or alkenyl groups have a chain length of C₁₈ or above It is preferred if the long chain alkyl or alkenyl groups of the fabric conditioning compounds are predominantly linear

The fabric conditioning compounds used in the compositions of the invention are preferably compounds that provide excellent softening, and are characterised by a chain melting Lβ to Lα transition temperature greater than 25 C, preferably greater than 35 C, most preferably greater than 45°C This Lβ to Lα transition can be measured by DSC as defined in " Handbook of Lipid Bilayers, D Marsh, CRC Press, Boca Raton, Florida, 1990 (pages 37 and 337)

Substantially insoluble fabric conditioning compounds in the context of this invention are defined as fabric conditioning compounds having a solubility less than 1 x 10^" wt % in deminerailised water at 20°C Preferably the fabric softening compounds have a solubility less than 1 x 10^" wt %, most preferably less than 1 x 10^" to 1 x 10^"

Preferred fabric conditioning compounds are quaternary ammonium compounds It is especially preferred if the fabric conditioning compound is a water insoluble quaternary ammonium material which comprises a compound having two C₁₂.ι₈ alkyl or alkenyl groups connected to the molecule via at least one ester link It is preferred if the quaternary ammonium material has two ester links present An especially preferred ester-linked quaternary ammonium material can be represented by the formula,

R¹

R¹ N⁺ _(CH₂)_n-T-R 2

Wherein each R group is independently selected from C_1-4 alkyl, hydroxyalkyl or C_2-4 alkenyl groups, and wherein each R group is independently selected from C_8-28 alkyl or alkenyl groups, O O

T is -O-C- or -C-O-, and n is an integer from 0-5

Di (tallowowyloxyethyl) dimethyl ammonium chloride is especially preferred

A second preferred type of quaternary ammonium material can be represented by the formula, (CH₂)_nOOCR²

(R¹)₃N^{^}-(CH₂)_n CH

(CH₂)_nOOCR²

wherein R , n and R are as defined above.

It is advantageous if the quaternary ammonium material is biologically biodegradable.

Preferred materials of this class such as 1,2 bis (hardened tallowoyloxy) -3- trimethylammonium propane chloride and their methods of preparation are, for example, described in US 4 137 180 (Lever Brothers). Preferably these materials comprise small amounts of the corresponding monoester as described in US 4 137 180, for example, 1- hardened tallowoyloxy-2-hydroxy-3-trimethylammonium propane chloride. Lecithins are also suitable.

The compositions of the invention, when used as main wash fabric washing compositions, will generally also contain one or more detergency builders. The total amount of detergency builder in the compositions will typically range from 5 to 80 wt%, preferably from 10 to 60 wt%.

Inorganic builders that may be present include sodium carbonate, if desired in combination with a crystallisation seed for calcium carbonate, as disclosed in GB 1 437 950 (Unilever); crystalline and amorphous aluminosilicates, for example, zeolites as disclosed in GB 1 473 201 (Henkel), amorphous aluminosilicates as disclosed in GB 1 473 202 (Henkel) and mixed crystalline/amorphous aluminosilicates as disclosed in GB 1 470 250 (Procter & Gamble); and layered silicates as disclosed in EP 164 514B (Hoechst). Inorganic phosphate builders, for example, sodium orthophosphate, pyrophosphate and tripolyphosphate are also suitable for use with this invention. The compositions of the invention preferably contain an alkali metal, preferably sodium, aluminosilicate builder. Sodium aluminosilicates may generally be incorporated in amounts of from 10 to 70% by weight (anhydrous basis), preferably from 25 to 50 wt%.

The alkali metal aluminosilicate may be either crystalline or amorphous or mixtures thereof, having the general formula: 0.8-1.5 Na₂O. Al₂O₃. 0.8-6 SiO₂

These materials contain some bound water and are required to have a calcium ion exchange capacity of at least 50 mg CaO/g. The preferred sodium aluminosilicates contain 1.5-3.5 SiO₂ units (in the formula above). Both the amorphous and the crystalline materials can be prepared readily by reaction between sodium silicate and sodium aluminate, as amply described in the literature. Suitable crystalline sodium aluminosilicate ion-exchange detergency builders are described, for example, in GB 1 429 143 (Procter & Gamble). The preferred sodium aluminosilicates of this type are the well-known commercially available zeolites A and X, and mixtures thereof.

The zeolite may be the commercially available zeolite 4A now widely used in laundry detergent powders. However, according to a preferred embodiment of the invention, the zeolite builder incorporated in the compositions of the invention is maximum aluminium zeolite P (zeolite MAP) as described and claimed in EP 384 070A (Unilever). Zeolite MAP is defined as an alkali metal aluminosilicate of the zeolite P type having a silicon to aluminium ratio not exceeding 1.33, preferably within the range of from 0.90 to 1.33, and more preferably within the range of from 0.90 to 1.20.

Especially preferred is zeolite MAP having a silicon to aluminium ratio not exceeding 1.07, more preferably about 1.00. The calcium binding capacity of zeolite MAP is generally at least 150 mg CaO per g of anhydrous material. Organic builders that may be present include polycarboxylate polymers such as polyacrylates, acrylic/maleic copolymers, and acrylic phosphinates; monomeric polycarboxylates such as citrates, gluconates, oxydisuccinates, glycerol mono-, di and trisuccinates, carboxymethyloxy succinates, carboxymethyloxymalonates, dipicolinates, hydroxyethyliminodiacetates, alkyl- and alkenylmalonates and succinates; and sulphonated fatty acid salts. This list is not intended to be exhaustive.

Especially preferred organic builders are citrates, suitably used in amounts of from 5 to 30 wt%, preferably from 10 to 25 wt%; and acrylic polymers, more especially acrylic/maleic copolymers, suitably used in amounts of from 0.5 to 15 wt%, preferably from 1 to 10 t%.

Builders, both inorganic and organic, are preferably present in alkali metal salt, especially sodium salt, form.

Compositions according to the invention may also suitably contain a bleach system. Fabric washing compositions may desirably contain peroxy bleach compounds, for example, inorganic persalts or organic peroxyacids, capable of yielding hydrogen peroxide in aqueous solution.

Suitable peroxy bleach compounds include organic peroxides such as urea peroxide, and inorganic persalts such as the alkali metal perborates, percarbonates, perphosphates, persilicates and persulphates. Preferred inorganic persalts are sodium perborate monohydrate and tetrahydrate, and sodium percarbonate.

Especially preferred is sodium percarbonate having a protective coating against destabilisation by moisture. Sodium percarbonate having a protective coating comprising sodium metaborate and sodium silicate is disclosed in GB 2 123 044B (Kao).

The peroxy bleach compound is suitably present in an amount of from 0.1 to 35 wt%, preferably from 0.5 to 25 wt%. The peroxy bleach compound may be used in conjunction with a bleach activator (bleach precursor) to improve bleaching action at low wash temperatures. The bleach precursor is suitably present in an amount of from 0.1 to 8 wt%, preferably from 0.5 to 5 wt%.

Preferred bleach precursors are peroxycarboxylic acid precursors, more especially peracetic acid precursors and pernoanoic acid precursors. Especially preferred bleach precursors suitable for use in the present invention are N,N,N',N.-tetracetyl ethylenediamine (TAED) and sodium noanoyloxybenzene sulphonate (SNOBS). The novel quaternary ammonium and phosphonium bleach precursors disclosed in US 4 751 015 and US 4 818 426 (Lever Brothers Company) and EP 402 971 A (Unilever), and the cationic bleach precursors disclosed in EP 284 292A and EP 303 520A (Kao) are also of interest.

The bleach system can be either supplemented with or replaced by a peroxyacid. examples of such peracids can be found in US 4 686 063 and US 5 397 501 (Unilever). A preferred example is the imido peroxycarboxylic class of peracids described in EP A 325 288, EP A 349 940, DE 382 3172 and EP 325 289. A particularly preferred example is phtalimido peroxy caproic acid (PAP). Such peracids are suitably present at 0.1 - 12%, preferably 0.5 - 10%.

A bleach stabiliser (heavy metal sequestrant) may also be present. Suitable bleach stabilisers include ethylenediamine terra-acetate (EDTA), the polyphosphonates such as Dequest (Trade Mark) and non-phosphate stabilisers such as EDDS (ethylene diamine di-succinic acid). These bleach stabilisers are also useful for stain removal especially in products containing low levels of bleaching species or no bleaching species.

An especially preferred bleach system comprises a peroxy bleach compound (preferably sodium percarbonate optionally together with a bleach activator), and a transition metal bleach catalyst as described and claimed in EP 458 397A ,EP 458 398A and EP 509 787A (Unilever).

The compositions according to the invention may also contain one or more enzyme(s). Suitable enzymes include the proteases, amylases, cellulases, oxidases, peroxidases and lipases usable for incorporation in detergent compositions Preferred proteolytic enzymes (proteases) are, catalytically active protein materials which degrade or alter protein types of stains when present as in fabric stains in a hydrolysis reaction They may be of any suitable origin, such as vegetable, animal, bacterial or yeast origin.

Proteolytic enzymes or proteases of various qualities and origins and having activity in various pH ranges of from 4-12 are available and can be used in the instant invention. Examples of suitable proteolytic enzymes are the stabilisins which are obtained from particular strains of B Subtilis B licheniformis. such as the commercially available subtilisins Maxatase (Trade Mark), as supplied by Gist Brocades N V., Delft, Holland, and Alcalase (Trade Mark), as supplied by Novo Industri A/S, Copenhagen, Denmark

Particularly suitable is a protease obtained from a strain of Bacillus having maximum activity throughout the pH range of 8-12, being commercially available, e.g. from Novo Industri A/S under the registered trade-names Esperase (Trade Mark) and Savinase (Trade-Mark). The preparation of these and analogous enzymes is described in GB 1 243 785 Other commercial proteases are Kazusase (Trade Mark obtainable from Showa-Denko of Japan), Optimase (Trade Mark from Miles Kali-Chemie, Hannover, West Germany), and Superase (Trade Mark obtainable from Pfizer of U.S.A.).

Detergency enzymes are commonly employed in granular form in amounts of from about 0.1 to about 3.0 wt% However, any suitable physical form of enzyme may be used.

The compositions of the invention may contain alkali metal, preferably sodium carbonate, in order to increase detergency and ease processing. Sodium carbonate may suitably be present in amounts ranging from 1 to 60 wt%, preferably from 2 to 40 wt% However, compositions containing little or no sodium carbonate are also within the scope of the invention.

Powder flow may be improved by the incorporation of a small amount of a powder structurant, for example, a fatty acid (or fatty acid soap), a sugar, an acrylate or acrylate/maleate copolymer, or sodium silicate One preferred powder structurant is fatty acid soap, suitably present in an amount of from 1 to 5 wt%

Other materials that may be present in detergent compositions of the invention include sodium silicate, antiredeposition agents such as cellulosic polymers, inorganic salts such as sodium sulphate, lather control agents or lather boosters as appropriate, proteolytic and lipolytic enzymes, dyes, coloured speckles, perfumes, foam controllers, fluorescers and decoupling polymers This list is not intended to be exhaustive

It is often advantageous if soil release polymers are present

The detergent composition when diluted in the wash liquor (during a typical wash cycle) will typically give a pH of the wash liquor from 7 to 10 5 for a main wash detergent

Particulate detergent compositions are suitably prepared by spray-drying a slurry of compatible heat-insensitive ingredients, and then spraying on or post-dosing those ingredients unsuitable for processing via the slurry The skilled detergent formulator will have no difficulty in deciding which ingredients should be included in the slurry and which should not

Particulate detergent compositions of the invention preferably have a bulk density of at least 400 g/1, more preferably at least 500 g/1 Especially preferred compositions have bulk densities of at least 650 g/litre, more preferably at least 700 g/litre

Such powders may be prepared either by post-tower densification of spray-dried powder, or by wholly non-tower methods such as dry mixing and granulation, in both cases a hiqh-speed mixer/granulator may advantageously be used Processes using high-speed mixer/granulators are disclosed, for example, in EP 340 013A, EP 367 339A, EP 390 251A and EP 420 317A (Unilever) Liquid detergent compositions can be prepared by admixing the essential and optional ingredients thereof in any desired order to provide compositions containing components in the requisite concentrations Liquid compositions according to the present invention can also be in compact form which means it will contain a lower level of water compared to a conventional liquid detergent

Any suitable method may be used to produce the compounds of the present invention In particular polymerisation of the sunscreen and/or SOQ and polymer as described in the examples may be used

The compounds of the invention may be produced either by reacting monomers to produce a polymer having an extinction co-efficient as recited in claim 1 with subsequent reaction with the sunscreen and/or SOQ to produce the compound Alternatively, and preferably, a preformed polymer having an extinction co-efficient as recited in claim 1 may be reacted with the sunscreen and/or SOQ to produce the compound

The compositions comprising the compounds of the present invention may be produced by any suitable method depending upon the physical form of the composition

The substrate may be any substrate that is prone to photofading on exposure to UV radiation including coloured substrates and white substrates that exhibit 'yellowing' on exposure For example the substrate may be a fabric, woven or non-woven, or other textile material Typically the substrate will be a fabric used for clothing manufacture Cotton fabrics, and cotton containing fabrics, have been found to give particularly advantageous results

Examples

The present invention will be further described with reference to the following examples Further modifications within the scope of the present invention will be obvious to the skilled man The examples according to the invention are denoted by a number Comparative examples are denoted by a letter

In Examples 1, 2 and 4 to 9 the unsubstituted polymers used to prepare the compound by reaction with the stated sunscreen and/or SOQ had an extinction co-efficient of

35 1 mol^" cm^" at wavelengths in the range 220-300 nm In Example 3 the unsubstituted polymer had an extinction co-efficient of 15 1 mol^" cm^" at wavelengths in this range

Example 1; Synthesis of PVA, 4-methoxy cinnamate (sunscreen) compound.

Polyvinyl alcohol, referred to herein as PVA (mwt 25K, 88% hydrolysed, 1 g) was dissolved in DMF (dimethyl formamide) (100 ml) and pyridine (0 5 ml) was added To the solution 4-methoxycinnamoyl chloride (0 44 g) in DMF (20 ml) was added The solution turned yellow and the stirring was continued at 20°C for 14 hours The solution was reduced in volume ( under reduced pressure) and acetone added to precipitate the ester which had been formed This was filtered, extracted with ethyl acetate (100 ml) The sample was dissolved in water (200 ml) and freeze dried to give a slightly off-white powder

The ester product was dissolved in water and the polymer was pressure dialysed for 2 days with a 10,000 molecular weight cut-off filter The identity of the product was confirmed by C and H NMR A UV visible spectrum for the compound was obtained in water showing the cinnamate peak at 310 nm, but no absorption above 400 nm and little absorption between 250 and 280 nm The degree of substitution of the 4- methoxycinnamate sunscreen onto the PVA polymer was found to be 1% by moles

The sunscreen groups were pendent on the PVA The compound was soluble in water aatt 2200°°CC aanndd hhaadd aann eexxttiinnccttiioonn coefficient of 7100 1 mol ^" cm ^" at the wavelength of maximal absorbance, 308 nm Example 2; synthesis of PVA 4-methoxy cinnamate (sunscreen) compound

The synthesis of Example 1 was repeated using the Scotten and Baumann method as given in Example 4 with sodium hydrogen carbonate as the base. The degree of substitution of the 4-methoxycinnamate (sunscreen) onto the PVA polymer was found to be 2% by moles with this method.

The sunscreen groups were pendent on the PVA, the compound was water-soluble at 20°C and had an extinction coefficient of 14,660 1 mol ^" cm ^" at the wavelength of maximal absorbance, 308 nm.

Example 3; synthesis of SCMC-4-methoxy cinnamate (sunscreen) compound

Following the preparation method of Example 1 high viscosity, sodium carboxy methyl cellulose (SCMC) was dissolved and reacted with 4-methoxy cinnamoyl chloride. The resultant solution was freeze-dried. A sample of the compound was dissolved in water and UV visible spectrum obtained. An absorption peak at 310 nm was obtained but no absorption above 400 nm was observed. The degree of substitution of the sunscreen on to the SCMC polymer was found to be 1% by moles.

Again the sunscreen groups were pendent, the compound was water-soluble at 20°C and hhaadd aann eexxttiinnccttiioonn ccoo<efficient of 24,900 1 mol ^" cm ^' at the wavelength of maximal absorbance, 311 nm.

Example 4; synthesis of PVA; 2-carboxy benzofuran compound (SOQ). (Schotten and Baumann synthesis).

2-Carboxy benzofuran chloride (2 g) was dissolved in dichloromethane (30 ml) and slowly added to PVA (1.5 g) in a water (50 ml) triethylamine (1 ml) mixture at 0°C. The reaction was stirred vigorously for 3 hours at 0°C over an ice bath. The water layer was separated and extracted with dichloromethane (2x50 ml) and the solution freeze dried to a white powder. The degree of substitution of the SOQ on the polymer was found to be 1%> by moles.

The SOQ groups were pendent, the compound was water-soluble at 20°C and had an extinction coefficient of 2,300 1 mol ^" cm ^" at the wavelength of maximal absorbance, 281 nm.

Example 5; synthesis of PVA-4-methoxy cinnamate sunscreen)-2-carboxy benzofuran (SOQ) compound

PVA (mwt 25K, 2g) was dissolved in DMF (200 ml) with warming. Triethylamine (2 ml) was added with stirring at 0°C to the solution. Separately, 4-methoxy cinnamoyl chloride (sunscreen; 0.45g) and 2-carboxy benzofuran (SOQ; O. lg) were dissolved in DMF (10 ml). The acid chloride solutions were slowly added at 0°C to the PVA. The reaction mixture was stirred overnight. The solution was filtered, reduced in volume (to 50 ml under reduced pressure), and precipitated with acetone (500 ml). The filtered solid was dissolved in water and pressure filtered with a molecular filter (cut off 10,000 Daltons). The dialysed solution was freeze dried. The white solid was submitted for NMR analysis.

The total degree of substitution of the SOQ and the sunscreen on the PVA was found to be 1% by moles. The SOQ and sunscreen groups were pendent and the compound was water-soluble at 20°C and had an extinction coefficient of 7,300 1 mol ^"' cm ^"' at the wavelength of maximal absorbance, 307 nm. Example 6; synthesis of PVA-4-acetoxy benzoate (sunscreen) compound

4-acetoxy benzoyl chloride (1 g) was dissolved in dichloromethane (30 ml) and slowly added to PVA (1 5 g) in a mixture of water (50 ml) at 0°C containing sodium hydrogen carbonate (1 g) at 0°C The reaction was stirred vigorously for 3 hours at 0°C over an ice bath The water layer was separated and extracted with dichloromethane (2 x 50 ml) and the solution freeze dried to a white powder

The degree of substitution of the sunscreen on the PVA was found to be 1 5% by moles The sunscreen groups were pendent and the compound was water-soluble at 20°C and had an extinction coefficient of 2,600 1 mol ^" cm ^" at the wavelength of maximal absorbance, 282 nm

Example 7; synthesis of PVA-bis(p-aminosulphonate)-triazine (SOQ) compound

Cyanuric chloride (10 g) was dissolved in acetone (100 ml) P-aminobezenesulphonic acid (19 g) was dissolved in water (200 ml) and the pH adjusted to 4 with hydrochloric acid The cyanuric chloride solution was slowly added to the aqueous phase with pH monitoring to maintain the pH 4-6 After the complete addition of cyanuric chloride the solution was stirred at 20°C for 2 hours. The pH was adjusted to pH 9 with sodium hydroxide solution keeping the solution below 10°C A white powder was precipitated with the addition of acetone which was bis(p-aminobenzene)-sulphonic acid cyanuric chloride The bis(p-aminobenzenesulphonic acid) cyanuric chloride (2 g) was dissolved in cold water and slowly added to PVA (mwt 25K 2 g) in water at 60°C with sodium hydroxide (0 01 M) The solution was stirred for three hours and cooled and then neutralised, reduced in volume and precipitated with acetone The white powder was freeze dried and NMR analysis carried out The degree of substitution of the sunscreen was found to be 0.8% by moles. The SOQ groups were pendent and the compound was water-soluble and had an extinction coefficient of 11,200 1 mol ^" cm ^" at the wavelength of maximal absorbance, 309 nm.

Example 8; synthesis of PVA-PABA (sunscreen)-2-carboxy benzofuran (SOQ) compound

PVA (mwt 25K, 2g) was dissolved in DMF (200 ml) with warming. Triethylamine (2 ml) was added with stirring to the solution at 0°C. Separately, 4-N, N- dimethylaminobenzoyl chloride (0.45g) (PABA) and 2-carboxy benzofuran (0. Ig) were dissolved in DMF (10 ml). The acid chloride solutions were slowly added at 0°C to the PVA solution. The reaction mixture was stirred overnight. The solution was filtered, reduced in volume to 50 ml at reduced pressure and precipitated with acetone (500 ml). The filtered solid was dissolved in water and pressure filtered with a molecular filter (cut off 10,000 Daltons). The dialysed solution was freeze dried. The white solid was analysed by NMR.

The degree of substitution of the PABA/SOQ on the polymer was found to be 3% by moles. The SOQ groups were pendent, the compound was water-soluble and had an extinction coefficient of 22,000 1 mol ^" cm ^" at the wavelength of maximal absorbance, 308 nm.

Example 9; Synthesis of PVA benzotriazole

2-(4-(Propel acid chloride) phenol) benzotriazole (0.25g) was dissolved in N-methyl pyrrolidone with stirring. A solution of PVA (100% hydrolysed, mwt 14,000, 2g) in N- methyl pyrrolidone (200 ml) was prepared and treated with the benzotriazole solution, pyridine (lg) and N-dimethyl amino pyridine (O. lg). The resultant solution was heated to 50°C and maintained at that temperature for 3 hours after which time it was cooled and filtered. The filtrate was evaporated to dryness and exhaustively extracted with acetone The solid so recovered was washed in a little warm water, dried, and analysed by NMR

The degree of substitution of the benzotriazole ester on the PVA polymer was found to be 0 78%) by moles The benzotriazole ester groups were pendant and had an extinction co-efficient of 29,000 1 mol^" cm^" at the wavelength of maximal absorbance, 340 nm

Example 10; Evaluation of Examples 1-9 of the Invention in the Reduction of the Photoloading of Dyes.

The reflectance value of several lOg samples of a coloured control cloth was measured by flash reflectance and imaging using a "spectroflash 500" reflectance meter to give an initial reflectance value

The cloth samples were placed in individual pots in a "Rotawash Linitest" machine, with 100 ml of wash solution comprising 1% linear alkyl benzene sulphonate (LAS) and (0 5%) sodium tripolyphosphate (STP), added to each pot To each pot, one of Examples 1-9 was added (0 04 g) to provide 0 04% of the polymer compound in the washing solution All the examples dissolved easily in the wash solution

The cloth samples were washed in the "Linitest" pots for 30 minutes at 40°C, then removed from the pots, rinsed twice with clean water and dried on a line The washed coloured cloths were subjected to simulated solar radiation treatment in an 'Atlas Weatherometer' for 20 hours After irradiation, the test cloths were measured again for reflectance and the reflectance reading and Δε results were used to assess the change in colour of the test cloths

Δε is the colour as defined by the CIELAB colourspace protocol A control experiment (A) using another 10 g test cloth of the same composition and washed in 1% LAS with 0 5% STP but with no compound of the present invention (control Example A) was carried out using the same washing conditions Control Example B, PVA (polymer with an extinction co-efficient of 35 1 mol^" cm^" in wavelength range 200-250 nm) without a sunscreen or SOQ attached was included in a repeat of Example A Control Example C (2-ethyl-hexyl(4-methoxy) cinnamate), i e the equivalent to 4-methoxy cinnamate used in Example 1 but without any polymer present, was used in a repeat of Example A control Control Example D (polyester substituted with the sunscreen of Example 1, mwt of polymer 2000, pre-substitution extinction co-efficient of 10,800 1 mol^" cm^" at wavelengths of 200-300 nm) was used in a repeat of Example A

The effects on the prevention of dye fading are given in Table 1 below The results are expressed, for each example of the invention, as the change in Δε with respect to the 'control' Example A

Table 1 , evaluation of the sun-fading benefit of Examples 1-9

The above results show that the complexes of Examples 1-9 exhibit a good anti- photofading effect when compared to the control A which did not contain a complex according to the invention or when compared to Control B which contained a polymer as according to the invention but not substituted with a sunscreen The higher is the value for the change in Δε, the better the anti-photofading effect i e less colour fading has occurred It can be seen that all the compounds of the invention inhibited photofading whereas the comparative examples only exhibited a very minor, or even detrimental, effect

It can be seen that when a polymer not having the presently claimed extinction coefficient is used (Example D) more colour fading on exposure to UV radiation occurred than with any of Examples 1-8, and indeed control Examples A-C Further the use of either a polymer (as according to the types recited herein) or a sunscreen alone (control experiments A-C) resulted in a negligible colour fading of the substrate

Example 11 fabric washing compositions comprising a compound of the invention

A granular laundry washing composition was prepared and a compound of the invention added as given below -

% by weight

Sodium alkylsulphate 7 80

Alkyl ether sulphate 1 90 nonionic (7EO) 9 50

C₁₆-C,₈ glucamide 1 60

Zeolite 20 00

Acrylic/maleic copolymer 6 90

Sodium citrate 2H₂O 11 50

Sodium silicate 8 00

Sodium carbonate and sesquicarbonate 8 00

Sodium sulphate 4 00

Minor ingredients 12 07

Soap 1 00

Minor ingredients include perfume, antifoam, functional polymers, enzymes etc Examples 10a - 0 25g of Example 1 was added 10b - 0 5g of Example 1 was added

10c - 0 75g of Example 1 was added lOd - 1 Og of Example 1 was added All products were stable on storage

Claims

CLAIMS:

1 A water-soluble or water-dispersible compound which is the reaction product of (i) an at least sparingly water soluble polymer having an extinction coefficient of less than 2000 1 mol^" cm^" at wavelengths in the range 220-300 nm with

(ii) at least one sunscreen molecule and/or singlet oxygen quencher molecule

2 A compound according to claim 1, wherein the polymer has an extinction co- efficient of less than 500 1 mol^" cm^"

3 A compound according to either of claims 1 or 2, wherein at least one sunscreen and/or singlet oxygen quencher is attached directly to the polymer

4 A compound according to any of claims 1 to 3, wherein at least one of the sunscreens and/or singlet oxygen quenchers are in a pendent group position on the polymer

5 A compound according to any one of the preceding claims, wherein the polymer is a homopolymer or copolymer of polyvinyl alcohols and/or carboxymethyl celluloses

A compound according to any one of the preceding claims, wherein the extinct iioonn ccooeeffffiicciieenntt ooff ttlhe compound is greater than 250 1 mol ^" cm ^" at wavelengths in the range 300-400 nm.

7 A compound according to anyone of the preceding claims, wherein the compound comprises at least one sunscreen and at least one singlet oxygen quencher

8 A compound according to anyone of the preceding claims, wherein the sunscreen is a carboxylic acid or carboxylic acid derivative 9 A compound according to claim 8, wherein the carboxylic acid or carboxylic acid derivative is a cinnamate or benzoate or derivative thereof

10 A compound according anyone of the preceding claims, wherein the singlet oxygen quencher has a rate constant of greater than 1 x 10 1 mol^" s^" with O

11 A compound according to claim 10, wherein the singlet oxygen quencher is a benzofuran, coumeric acid or derivative thereof

12 A compound according to any preceding claim, having a degree of substitution of sunscreen and/or singlet oxygen quencher on the polymer of 0 1% to 15% by moles

13 A composition comprising at least one active ingredient and a compound as defined in any one of the preceding claims

14 A composition according to claim 13 wherein the active ingredient is a surface active agent and/or fabric conditioning compound

15 A method of reducing photofading by UV radiation of a substrate and/or increasing the sun protection factor of a substrate by treatment with a compound or composition as defined in any one of the preceding claims

16 A method according to claim 15, wherein the substrate is a fabric