Abstract:
The present invention relates to compositions comprising a photosensitizer that can be used to provide aqueous fluids with bleaching capabilities, aqueous fluid photobleaching compositions having bleaching capabilities and processes of making and using same. Such compositions can provide bleaching and/or cleaning benefits that are similar to or better than hydrogen peroxide bleaching systems.

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS  
       [0001]     This application claims priority under 35 U.S.C. § 119(e) to U.S. Provisional Application Ser. No. 60/582,705 filed Jun. 24, 2004. 
     
    
     FIELD OF THE INVENTION  
       [0002]     The present invention relates to photobleaching compositions having bleaching capabilities, and processes of making and using same.  
       BACKGROUND OF THE INVENTION  
       [0003]     Conventional bleaching compositions typically employ hydrogen peroxide as a bleaching species or as an intermediate that is converted into a peracid. Such systems can provide effective bleaching. Unfortunately it is difficult to formulate stable versions of such systems and such systems are not volume efficient as the requisite bleaching components make up a large volume of any formulation. While photobleaching systems do not suffer from the formulation and volume issues of hydrogen peroxide systems, photobleaching systems tend to be less effective as the short life of the bleaching species requires that photosensitizer, oxygen, light and the situs to be bleach be present simultaneously. In addition, the choice of effective photobleaches used in traditional photobleaching systems is limited as photobleaches generally must be capable of being adsorbed on the soiled portion of the situs. As a result, photobleach systems would be attractive if the life of the bleaching species could be extended to permit diffusion of such species in wash liquor.  
       SUMMARY OF THE INVENTION  
       [0004]     The present invention relates to photobleaching compositions comprising a photosensitizer that can be used to provide an aqueous fluid with bleaching capabilities, aqueous fluid cleaning compositions having photobleaching capabilities and processes of making and using same.  
         [0005]     These and other aspects, features and advantages will become apparent to those of ordinary skill in the art from a reading of the following detailed description and the appended claims. 
     
    
     DETAILED DESCRIPTION OF THE INVENTION  
       [0000]     Definitions  
         [0006]     As used herein, the term “photobleaching composition” includes, unless otherwise indicated, granular or powder-form all-purpose or “heavy-duty” washing agents, especially cleaning detergents; liquid, gel or paste-form all-purpose washing agents, especially the so-called heavy-duty liquid types; liquid fine-fabric detergents; hand dishwashing agents or light duty dishwashing agents, especially those of the high-foaming type; machine dishwashing agents, including the various tablet, granular, liquid and rinse-aid types for household and institutional use; liquid cleaning and disinfecting agents, including antibacterial hand-wash types, cleaning bars, mouthwashes, denture cleaners, car or carpet shampoos, bathroom cleaners; hair shampoos and hair-rinses; shower gels and foam baths and metal cleaners; as well as cleaning auxiliaries such as bleach additives and “stain-stick” or pre-treat types.  
         [0007]     The term “fabrics” and “fabric” used herein the term encompasses articles of clothing, linen, drapery, and clothing accessories. The term also encompasses other items made in whole or in part of fabric, such as tote bags, furniture covers, tarpaulins and the like.  
         [0008]     The term “soil” means any undesirable substance on a fabric. By the terms “water-based” or “hydrophilic” soils, it is meant that the soil comprised water at the time it first came in contact with the fabric article, or the soil retains a significant portion of water on the fabric article. Examples of water-based soils include, but are not limited to beverages, many food soils, water soluble dyes, bodily fluids such as sweat, urine or blood, outdoor soils such as grass stains and mud.  
         [0009]     As used herein, “aqueous fluid” means any liquid or mixture of liquids that comprises greater than 5%, greater than 25%, greater than 50% or alternatively greater than 90% water.  
         [0010]     As used herein the word “soluble” when used to describe one or more “photosensitizers” means capable of forming a solution at a concentration of at least 1×10 −8  molar in water at an in-use pH of from 10 to 8.  
         [0011]     As used herein, the articles a and an when used in a claim, for example, “an emulsifier” or “a photosensitizer” is understood to mean one or more of the material that is claimed or described.  
         [0012]     Unless otherwise noted, all component or composition levels are in reference to the active level of that component or composition, and are exclusive of impurities, for example, residual solvents or by-products, which may be present in commercially available sources.  
         [0013]     All percentages and ratios are calculated by weight unless otherwise indicated. All percentages and ratios are calculated based on the total composition unless otherwise indicated.  
         [0014]     All temperatures are in degrees Celsius (° C.) unless otherwise specified. All measurements are in SI units unless otherwise specified.  
         [0015]     It should be understood that every maximum numerical limitation given throughout this specification includes every lower numerical limitation, as if such lower numerical limitations were expressly written herein. Every minimum numerical limitation given throughout this specification will include every higher numerical limitation, as if such higher numerical limitations were expressly written herein. Every numerical range given throughout this specification will include every narrower numerical range that falls within such broader numerical range, as if such narrower numerical ranges were all expressly written herein.  
         [0016]     All documents cited are, in relevant part, incorporated herein by reference; the citation of any document is not to be construed as an admission that it is prior art with respect to the present invention.  
         [0000]     Photobleaching Compositions  
         [0017]     Applicants have discovered that certain photosensitizer compositions are unexpectedly suitable for incorporation into aqueous fluids. Suitable photosensitizer compositions typically contain a photosensitizer, and an extender, and may contain optional ingredients such as anionic, cationic, nonionic, and zwitterionic surfactants. Solid compositions, based on total weight of said composition, may comprise from about 0.1% to about 50%, from about 1% to about 25%, or even from about 5% to about 20% of a photosensitizer; from about 1% to about 99.9%, from about 5% to about 90%, or from even from about 10% to about 50% of an extender with the balance of said compositions being a an optional/adjunct. Such solid compositions include, but are not limited to, powders and granules.  
         [0018]     Fluid photosensitizer compositions may comprise, based on the total weight of said composition, from about 0.1% to about 50%, from about 1% to about 25%, or even from about 5% to about 20% of a photosensitizer; from about 1% to about 99.9%, from about 5% to about 90%, or from even from about 10% to about 50% of an extender with the balance of said compositions with the balance of said photobleaching compositions being an aqueous fluid or a mixture of an aqueous fluid and an optional/adjunct ingredient.  
         [0019]     The aforementioned solid photosensitizer compositions and fluid photosensitizer compositions may be packaged in a kit containing instructions for use.  
         [0020]     Unlike common photobleaching compositions, the aforementioned compositions do not require that the photosensitizer, oxygen, light and the situs to be present simultaneously as it is believed that the bleaching species is formed in solution and, due to the use of an extender, such species has sufficient life to diffuse to the soiled portion of the situs. In addition, the use of an extender increases the formulator&#39;s choice of photosensitizers, as such photosensitizers need not be capable of being adsorbed on the soiled portion of the situs.  
         [0000]     Process of Making  
         [0021]     While not being bound by theory, Applicants believe that formation and concentration of bleaching species other than singlet oxygen is a function of at least 4 variables: reactant concentration, time, oxygen concentration of the reactant mixture, and photon flux. As a result, while Applicants, photobleaching compositions may be made by combining a photosensitizer, and extender, any aqueous fluid solvent and any optional ingredients, light energy coming from light having a wavelength that can be absorbed by that of the photosensitizer is minimized and/or the oxygen amount of oxygen in the composition or to which the composition is exposed is minimized. For the purposes of the present invention the wavelength of light that any photosensitizer will absorb is determined by the Light Absorbance Test found in the Test Methods Section of the present specification. For purposes of the present invention the minimization of light energy that can be absorbed by the photosensitzer means that during processing such compositions are generally exposed to such wavelength of light at one of the following levels: less than about 1 milliwatt per square meter of solution surface exposed to said light, less than about 1×10 −4  watts per square meter of solution surface exposed to said light, or even less than about 1 microwatt per square meter of solution surface exposed said light. For purposes of the present invention the minimization of oxygen means that during processing the compositions comprise less than about 1×10 −2  moles of oxygen per liter, less than about 1×10 −3  moles of oxygen per liter, and even less than about 1×10 −4  moles of oxygen per liter.  
         [0022]     In use photobleaching compositions may be made by exposing the photobleaching compositions described herein to light having a wavelength that can be absorbed by that of the photosensitizer and sufficient oxygen to provide said composition with a dissolved oxygen content of greater than about 1×10 −9  moles per liter, greater than about 1×10 −6  moles per liter, or even greater than about 1×10 −3  moles per liter. The amount of such light energy that is required to produce such in use compositions is typically greater than about 1×10 −4  milliwatts per square meter of solution surface exposed to said light, greater than about 1 milliwatt per square meter of solution surface exposed to said light, or even greater than 1×10 −2  watts/square meter of solution surface exposed to said light. Said light energy may be provided by any suitable source, including but not limited a light source located in a domestic appliance, said appliance being suitable for cleaning and/or fabrics.  
         [0000]     Method of Using  
         [0023]     A situs inter alia a surface or fabric, may be bleached by contacting at least a portion said situs with a liquid version of Applicants&#39; photobleaching compositions wherein the extender and photosensitizer are dissolved in an aqueous fluid or dissolve while in contact with the situs. Such compositions may be in neat form or diluted in a wash liquor. As will be appreciated by the skilled artisan, contacting includes but is not limited to, immersion and spraying. After such contacting step, the situs may be optionally washed and/or rinsed Such in use composition may be made during the time that they are in contact with the item or items that are to be cleaned.  
         [0000]     Suitable Materials  
         [0024]     Suitable materials for making Applicants&#39; photobleaching compositions include any known photosensitizer or mixture of photosensitizers that generate singlet oxygen or superoxide and that are soluble in an aqueous fluid. Suitable singlet oxygen photosensitizers include water-soluble porphyrins and phthalocyanines and their complexes with a photoactive metal/non-metal selected from Sn, Ge, Pt, Pd, Pb, Si, Zn, Al. For example, sulfonated zinc phthalocyanine, sulphonated aluminum phthalocyanine, silicon phthaolcyanine-di-isoPEG 384 and other water soluble phthalocyanines described in U.S. Pat. No. 5,916,481, zinc-5,10,15,20-tetra(4-pyridyl)-21H, 23H-porphine tetrakis(methochloride), porphine tetrakis benzoic acid sodium salt. Other suitable photosensitizers include water-soluble aromatic and heteroaromatic singlet oxygen photosensitizers such as, acridine carboxylic acid, perylene tetracarboxylic acid, pyrenesulfonic acid, 9-Fluorenone-1-carboxylic acid. Water-soluble photosensitizers such as methylene blue, rose Bengal, riboflavin. Examples of superoxide photosensitizers include triethanolamine substituted silicon phthalocyanines described in U.S. Pat. No. 6,225,273 and curcumin. Suitable water-soluble photosensitizers may be obtained from Sigma-Aldrich of Milwaukee, Wis. U.S.A., Ciba Specialty Chemicals Inc. of Basel, Switzerland or prepared by literature procedures.  
         [0025]     Suitable extenders include species that form adducts with singlet oxygen or superoxide. For example, suitable singlet oxygen extenders include extenders selected from the group consisting of furan, substituted furans, polyethoxylates, alkyl polyethoxylates, polynuclear aromatics, imidazole, substituted imidazoles, pyrrole, substituted pyrroles, and mixtures thereof. Examples of suitable extenders include: Furfuryl alcohol, 2-Furoic acid, 3-Furoic acid, 3-Furanmethanol, 2-benzofurancarboxylic acid, 1,4-Dimethylnaphthalene, Furfural, 2,5 dimethyl furan and mixtures thereof. Such materials may be obtained from Sigma-Aldrich of Milwaukee, Wis. U.S.A. Additional materials that may be useful as extenders include surfactants, such as alkyl ethoxylates, for example, Neodol™ 91-2.5 which is supplied Shell Chemicals of Houston, Tex. U.S.A. Such surfactants can function as cleaning adjuncts and as extenders.  
         [0000]     Optional/Adjunct Ingredients  
         [0026]     While not essential for the purposes of the present invention, the non-limiting list of adjuncts illustrated hereinafter are suitable for use in the instant photobleaching compositions and may be desirably incorporated in preferred embodiments of the invention, for example to assist or enhance cleaning performance, for treatment of the substrate to be cleaned, or to modify the aesthetics of the photobleaching composition as is the case with perfumes, colorants, dyes or the like. The precise nature of these additional components, and levels of incorporation thereof, will depend on the physical form of the composition and the nature of the cleaning operation for which it is to be used. Suitable adjunct materials include, but are not limited to, additional bleach activators, surfactants, builders, chelating agents, dye transfer inhibiting agents, dispersants, enzymes, and enzyme stabilizers, catalytic metal complexes, polymeric dispersing agents, clay and soil removal/anti-redeposition agents, brighteners, suds suppressors, dyes, perfumes, structure elasticizing agents, fabric softeners, carriers, hydrotropes, processing aids and/or pigments. In addition to the disclosure below, suitable examples of such other adjuncts and levels of use are found in U.S. Pat. Nos. 5,576,282, 6,306,812 B1 and 6,326,348 B1.  
         [0027]     Additional Bleach Activators—Suitable bleach activators that may be used in conjunction with Applicants&#39; organic activator include, but are not limited to, tetraacetyl ethylene diamine (TAED), benzoylcaprolactam (BzCL), 4-nitrobenzoylcaprolactam, 3-chlorobenzoylcaprolactam, benzoyloxybenzenesulphonate (BOBS), nonanoyloxybenzenesulphonate (NOBS), phenyl benzoate (PhBz), decanoyloxybenzenesulphonate (C 10 -OBS), benzoylvalerolactam (BZVL), octanoyloxybenzenesulphonate (C 8 —OBS), perhydrolyzable esters, perhydrolyzable carbonates, perhydrolyzable imides and mixtures thereof.  
         [0028]     Surfactants—Preferably, the photobleaching compositions of the present invention comprise a surfactant or surfactant system wherein the surfactant can be selected from nonionic and/or anionic and/or cationic surfactants and/or ampholytic and/or zwitterionic and/or semi-polar nonionic surfactants.  
         [0029]     The surfactant or surfactant system is typically present at a level of from about 0.1%, preferably from about 1%, more preferably from about 5% by weight of the photobleaching compositions to about 99.9%, preferably about 80%, more preferably about 35%, most preferably about 30% by weight of the photobleaching composition.  
         [0030]     Builders—The photobleaching compositions of the present invention preferably comprise one or more detergent builders or builder systems. When present, the compositions will typically comprise at least about 1% builder, preferably at least about 5%, more preferably from about 10% to about 80%, preferably to about 50%, more preferably to about 30% by weight of the photobleaching composition.  
         [0031]     Builders include, but are not limited to, the alkali metal, ammonium and alkanolammonium salts of polyphosphates, alkali metal silicates, alkaline earth and alkali metal carbonates, aluminosilicate builders polycarboxylate compounds, ether hydroxypolycarboxylates, copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1,3,5-trihydroxy benzene-2,4,6-trisulphonic acid, and carboxymethyloxysuccinic acid, the various alkali metal, ammonium and substituted ammonium salts of polyacetic acids such as ethylenediamine tetraacetic acid and nitrilotriacetic acid, as well as polycarboxylates such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene 1,3,5-tricarboxylic acid, carboxymethyloxysuccinic acid, and soluble salts thereof.  
         [0032]     Chelating Agents—The photobleaching compositions of the present invention may also optionally contain one or more copper, iron and/or manganese chelating agents.  
         [0033]     If utilized, chelating agents will generally comprise from about 0.1%, more preferably from about 3.0% to about 15% by weight of the photobleaching composition.  
         [0034]     Dye Transfer Inhibiting Agents—The photobleaching compositions of the present invention may also include one or more dye transfer inhibiting agents. Suitable polymeric dye transfer inhibiting agents include, but are not limited to, polyvinylpyrrolidone polymers, polyamine N-oxide polymers, copolymers of N-vinylpyrrolidone and N-vinylimidazole, polyvinyloxazolidones and polyvinylimidazoles or mixtures thereof.  
         [0035]     When present in the photobleaching compositions of the present invention, the dye transfer inhibiting agents are present at levels from about 0.0001%, more preferably from about 0.01%, most preferably from about 0.05% by weight of the photobleaching compositions to about 10%, more preferably about 2%, most preferably about 1% by weight of the photobleaching composition.  
         [0036]     Dispersants—The photobleaching compositions of the present invention can also contain dispersants. Suitable water-soluble organic salts are the homo- or co-polymeric acids or their salts, in which the polycarboxylic acid comprises at least two carboxyl radicals separated from each other by not more than two carbon atoms.  
         [0037]     Enzymes—The photobleaching compositions can comprise one or more enzymes that provide cleaning performance and/or fabric care benefits. Examples of suitable enzymes include, but are not limited to, hemicellulases, peroxidases, proteases, cellulases, xylanases, lipases, phospholipases, esterases, cutinases, pectinases, keratanases, reductases, oxidases, phenoloxidases, lipoxygenases, ligninases, pullulanases, tannases, pentosanases, malanases, β-glucanases, arabinosidases, hyaluronidase, chondroitinase, laccase, and known amylases, or mixtures thereof.  
         [0038]     Enzyme Stabilizers—Enzymes for use in detergents can be stabilized by various techniques including the use of water-soluble sources of calcium and/or magnesium ions in the photobleaching compositions.  
         [0039]     Bleach Boosting Compounds—The photobleaching compositions herein may comprise one or more bleach boosting compounds such as a dioxirane, an oxaziridine, or an oxaziridinium or compounds capable of forming such species in situ.  
         [0040]     Among suitable bleach boosting compounds for use in accordance with the present invention are cationic imines, zwitterionic imines, anionic imines and/or polyionic imines having a net charge of from about +3 to about −3, and mixtures thereof. These imine bleach boosting compounds of the present invention include those of the general structure:  
                         
        where for Formula I above, R 1 -R 4  may be a hydrogen or an unsubstituted or substituted radical selected from the group consisting of phenyl, aryl, heterocyclic ring, alkyl and cycloalkyl radicals. 
 
 Among preferred bleach boosting compounds are zwitterionic bleach boosters, which are described in U.S. Pat. Nos. 5,576,282 and 5,718,614. Other bleach boosting compounds include cationic bleach boosters such as those described in U.S. Pat. Nos. 5,360,569, and 5,370,826. 
       
 
         [0042]     Catalytic Metal Complexes—Applicants&#39; photobleaching compositions may include catalytic metal complexes. One type of metal-containing bleach catalyst is a catalyst system comprising a transition metal cation of defined bleach catalytic activity, such as copper, iron, titanium, ruthenium, tungsten, molybdenum, or manganese cations, an auxiliary metal cation having little or no bleach catalytic activity, such as zinc or aluminum cations, and a sequestrate having defined stability constants for the catalytic and auxiliary metal cations, particularly ethylenediaminetetraacetic acid, ethylenediaminetetra (methylenephosphonic acid) and water-soluble salts thereof. Such catalysts are disclosed in U.S. Pat. No. 4,430,243.  
         [0043]     If desired, the photobleaching compositions herein can be catalyzed by means of a manganese compound. Such compounds and levels of use are well known in the art and include, for example, the manganese-based catalysts disclosed in U.S. Pat. No. 5,576,282.  
         [0044]     Cobalt bleach catalysts useful herein are known, and are described, for example, in U.S. Pat. No. 5,597,936, U.S. Pat. No. 5,595,967.  
         [0045]     Compositions herein may also suitably include a transition metal complex of a macropolycyclic rigid ligand—abbreviated as “MRL”. As a practical matter, and not by way of limitation, the photobleaching compositions and cleaning processes herein can be adjusted to provide on the order of at least one part per hundred million of the active MRL species in the aqueous washing medium, and will preferably provide from about 0.005 ppm to about 25 ppm, more preferably from about 0.05 ppm to about 10 ppm, and most preferably from about 0.1 ppm to about 5 ppm, of the MRL in the wash liquor.  
         [0046]     Preferred transition-metals in the instant transition-metal bleach catalyst include manganese, iron and chromium. Preferred MRL&#39;s herein are a special type of ultra-rigid ligand that is cross-bridged such as 5,12-diethyl-1,5,8,12-tetraazabicyclo[6.6.2]hexadecane.  
         [0047]     Suitable transition metal MRLs are readily prepared by known procedures, such as taught for example in WO 00/332601, and U.S. Pat. No. 6,225,464.  
       Test Methods  
       [0000]     Light Absorbance Test (Process for determining wavelength of light absorbed by a photosensitizer)  
         [0000]    
       
          1.) Dissolve a sufficient amount of photosensitizer of choice in the solvent of choice to obtain a maximum absorbance, between 250 nanometers and 700 nanometers, of 1.  
          2.) For purposes of this invention, any wavelength of light wherein such photosensitizer has an absorbance of 0.01 is considered to be a wavelength that is absorbed by the photosensitizer  
       
     
       EXAMPLES  
     Example 1  
       [0050]     The following bleach composition is prepared by combining sulphonated zinc phthalocyanine, imidazole and the cleaning adjuncts while avoiding exposure to light.  
                                                       Sulphonated zinc phthalocyanine   0.1%           Imidazole     1%           Cleaning adjuncts   Balance                      
 
 100 grams of the above described bleach composition is added to 30 liters of aqueous wash liquor in a suitable washing machine and the wash liquor is illuminated with a light source emitting in at least one of the absorbance peaks of the sulphonated zinc phthalocyanine while being agitated for a period of 15 minutes. The wash liquor is removed and the fabrics are rinsed. 
 
       Example 2  
       [0051]     The following bleach composition is prepared by combining silicon phthalocyanine-di-isoPEG 384, benzofuran carboxylic acid and the cleaning adjuncts while avoiding exposure to light.  
                                                       Silicon phthalocyanine-di-isoPEG 384   0.01%           Benzofuran carboxylic acid    0.5%           Cleaning adjuncts   Balance                      
 
 100 grams of the above described bleach composition is added to 30 liters of aqueous wash liquor in a suitable washing machine and the wash liquor is illuminated with a light source emitting in at least one of the absorbance peaks of the silicon phthalocyanine-di-isoPEG 384 while being agitated for a period of 15 minutes. The wash liquor is removed and the fabrics are rinsed. 
 
       Example 3  
       [0052]     The following bleach composition is prepared by combining acridine carboxylic acid, 2-furoic acid and the cleaning adjuncts while avoiding exposure to light.  
                                                       Acridine carboxylic acid   0.5%           2-furoic acid     5%           Cleaning adjuncts   Balance                      
 
 100 grams of the above described bleach composition is added to 30 liters of aqueous wash liquor in a suitable washing machine and the wash liquor is illuminated with a light source emitting in at least one of the absorbance peaks of the acridine carboxylic acid while being agitated for a period of 15 minutes. The wash liquor is removed and the fabrics are rinsed. 
 
       Example 4  
       [0053]     The following bleach composition is prepared by combining 9-fluorenone-1-carboxylic acid, 5-benzimidazolecaboxylic acid and the cleaning adjuncts while avoiding exposure to light.  
                                                       9-fluorenone-1-carboxylic acid   0.1%           5-benzimidazolecaboxylic acid     1%           Cleaning adjuncts   Balance                      
 
 100 grams of the above described bleach composition is added to 30 liters of aqueous wash liquor in a suitable washing machine and the wash liquor is illuminated with a light source emitting in at least one of the absorbance peaks of the 9-fluorenone-1-carboxylic acid while being agitated for a period of 15 minutes. The wash liquor is removed and the fabrics are rinsed. 
 
         [0054]     While particular embodiments of the present invention have been illustrated and described, it would be obvious to those skilled in the art that various other changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore intended to cover in the appended claims all such changes and modifications that are within the scope of this invention.