HK1195095A - Calcium sequestering composition - Google Patents

Abstract

This invention relates to compositions which are capable of sequestering calcium ions and are derived in part from renewable carbohydrate feedstocks. The calcium sequestering compositions are mixtures containing one or more hydroxycarboxylic acid salts, one or more oxoacid anion salts, and one or more citric acid salts.

Description

Calcium sequestering compositions

Cross Reference to Related Applications

This application claims priority to united states provisional patent application No. 61/477,774, filed on 21/4/2011, the contents of which are incorporated herein by reference in their entirety.

Technical Field

The present invention relates to compositions capable of sequestering calcium ions and derived in part from renewable carbohydrate feedstocks. The calcium sequestering compositions comprise one or more salts of hydroxycarboxylic acids, including hydroxymonocarboxylic acids and hydroxydicarboxylic acids, one or more salts of suitable oxoacid anions, and one or more salts of citric acid.

Background

Hydroxycarboxylic acids and salts of hydroxycarboxylic acids are described as chelating agents capable of chelating metal ions in solution (Mehltretter,1953; Abbadi, 1999). Hydroxycarboxylic acid salts generally perform poorly as chelating agents for metal ions such as calcium and magnesium compared to common chelating agents such as Sodium Tripolyphosphate (STPP), Ethylenediaminetetraacetate (EDTA) or Nitrilotriacetate (NTA). In spite of having a low chelating capacity, hydroxycarboxylic acid salts can be of interest because they are generally biodegradable, non-toxic, and derived from renewable resources such as carbohydrates. Therefore, it would be advantageous to utilize hydroxycarboxylic acid salts as alternative chelating agents to STPP and EDTA, especially in applications where the compounds may be emitted to the environment. The performance of the hydroxycarboxylic acid salts as chelating agents for hard water ions can be enhanced by the addition of suitable oxoacid anion compounds, such as borates and aluminates. The improvement in performance results from the formation of a diester complex between two adjacent hydroxyl groups of a salt of a hydroxycarboxylic acid and a borate or aluminate, as described by van Duin et al (Carb. Res.1987,162,65-78and J. chem. Soc. Dalton trans.1987,8, 2051-. Work by van Duin et al shows that diester complex formation occurs with compounds containing two vicinal hydroxyl groups that are preferably present in the threo configuration. The stability of the complex is pH dependent and increases at higher pH values. Complexes formed between salts of hydroxycarboxylic acids and sodium borate or sodium aluminate are described as calcium chelators for detergent applications (Hessen, U.S. Pat. No. 4,000,083; Tumerman, U.S. Pat. No. 3,798,168; and Miralles et al, U.S. Pat. No. 8,153,573). Thus, complexes formed between salts of polyhydroxycarboxylic acids and salts of suitable oxoacid anions, such as sodium aluminate and sodium borate, are known to be useful as divalent metal ion chelators for applications such as detergents. Surprisingly, we have found that the calcium sequestering properties of complexes formed between polyhydroxycarboxylates and suitable salts of oxoacid anions can be improved by the addition of certain chelating agents, such as citrates. Our findings were unexpected in view of the fact that van Duin et al described that the performance of citrate was not improved by the addition of sodium aluminate or sodium borate (carb. res.1987,162, 65-78).

Many of the compounds traditionally used as metal chelators are phosphorus-based. The use of phosphorus compounds in applications where the material is discharged into surface water is still limited by environmental regulations. These regulations have prompted the need for environmentally acceptable materials that can be used as metal chelators for a variety of applications.

One application in which metal chelating agents are useful is in detergent formulations. Detergents are cleaning mixtures consisting essentially of surfactants, builders, bleaching agents, enzymes and fillers. The two main components are surfactant and builder. Surfactants are responsible for emulsifying oils and greases, while adjuvants are added to extend or enhance the cleaning performance of the surfactants. Builders can be a single substance or a mixture of substances and typically serve multiple functions. One important builder function is to sequester metal cations, typically calcium and magnesium cations in hard water. The adjunct acts as a water softener by sequestering calcium and magnesium cations, thereby preventing the formation of water-insoluble salts between cationic and anionic ingredients in wash solutions such as surfactants and carbonates. In the case of laundry detergents, builders also help to prevent the main cause of grime retention on cationic bonded cotton, cotton. Other functions of the adjunct include increasing alkalinity of the detergent solution, anti-surfactant micelle flocculation, and corrosion inhibition.

Builders first used in commercial detergents were phosphates and phosphate derivatives. Sodium Tripolyphosphate (STPP) was once the most common builder in consumer and industrial detergents. Phosphate builders are also marketed as corrosion inhibitors for metal surfaces in washing machines and dishwashers. Phosphate has been phased out of detergents over the last 40 years, mainly due to environmental problems related to eutrophication and eventual oxygen deficit caused by discharge of phosphate-rich wastewater into surface waters (Lowe, 1978). High performance alternatives to phosphates in detergents are still being sought.

Conventional detergents used in the vehicle care, food and beverage (e.g., dairy, cheese, sugar, meat, food and brewery and other beverage industries), warewashing, and laundry industries include alkaline detergents. Alkaline detergents, especially for institutional and commercial use, typically contain phosphates, nitrilotriacetic acid (NTA) and ethylenediaminetetraacetic acid (EDTA). Phosphates, NTA and EDTA are components commonly used in detergents to aid in detergency and to chelate metal ions such as calcium, magnesium and iron.

In particular, NTA, EDTA or polyphosphates such as sodium tripolyphosphate and their salts are used in detergents because of their ability to dissolve inorganic salts and/or soils that are already present. When calcium, magnesium and iron salts precipitate, crystals may adhere to the cleaned surface and cause adverse effects. For example, calcium carbonate precipitation on the surface of ware can adversely affect the aesthetic appearance of the ware and produce an unclean appearance. In the laundering area, if calcium carbonate precipitates and adheres to the surface of fabrics, the crystals can make the fabrics feel harder and rougher to the touch. In the food and beverage industry, calcium carbonate residues can affect the acidity level of foods. By preventing hardness precipitation, the ability of NTA, EDTA and polyphosphates to remove metal ions can promote detergency of the solution, aid in soil removal and/or prevent redeposition of soil into the wash liquor or wash water.

Although effective, phosphate and NTA are subject to government regulations due to environmental and health concerns. Although EDTA is currently unregulated, it is believed that government regulations may be enforced due to environmental persistence. There is therefore a need in the art for alternative, and preferably environmentally friendly, cleaning compositions that can replace the performance of phosphorus-containing compounds such as phosphate, phosphonate, phosphinate and propionate phosphinate polymers, as well as non-aminocarboxylates such as NTA and EDTA.

Summary of The Invention

The present invention provides a calcium sequestering composition comprising: a combination of at least one salt of a hydroxycarboxylic acid selected from the group consisting of at least one salt of a hydroxymonocarboxylic acid, at least one salt of a hydroxydicarboxylic acid, a combination of at least one salt of a hydroxymonocarboxylic acid and at least one salt of a hydroxydicarboxylic acid, at least one suitable salt of an oxoacid anion such as, for example, a borate or aluminate, and at least one salt of a citric acid. Generally, the salt of the hydroxymonocarboxylic acid may include at least one salt of glycolic acid, at least one salt of gluconic acid, and at least one salt of 5-keto-gluconic acid. In one embodiment, the at least one salt of glycolic acid comprises sodium glycolate, potassium glycolate, lithium glycolate, zinc glycolate, ammonium glycolate, or mixtures thereof. In another embodiment, the at least one salt of gluconic acid may include sodium gluconate, potassium gluconate, lithium gluconate, zinc gluconate, ammonium gluconate or mixtures thereof. In further embodiments, the at least one salt of a 5-keto-gluconic acid comprises sodium 5-keto-gluconate, potassium 5-keto-gluconate, lithium 5-keto-gluconate, zinc 5-keto-gluconate, ammonium 5-keto-gluconate, or a mixture thereof.

In addition, the hydroxy dicarboxylate salt may generally comprise at least one salt of glucaric acid, at least one salt of tartaric acid, at least one salt of tartronic acid, at least one salt of xylaric acid, at least one salt of galactaric acid, or mixtures thereof. In one embodiment, the at least one salt of glucaric acid comprises disodium glucarate, sodium potassium glucarate, dipotassium glucarate, zinc glucarate, diammonium glucarate, dilithium glucarate, lithium sodium glucarate, lithium potassium glucarate, or mixtures thereof. In another embodiment, the at least one salt of tartaric acid comprises disodium tartrate, sodium potassium tartrate, dipotassium tartrate, dilithium tartrate, lithium sodium tartrate, lithium potassium tartrate, zinc tartrate, diammonium tartrate, or mixtures thereof. In another embodiment, the at least one salt of tartronic acid comprises disodium tartronate, sodium potassium tartronate, dipotassium tartronate, dilithium tartronate, lithium sodium tartronate, lithium potassium tartronate, zinc tartronate, diammonium tartronate, or mixtures thereof.

It is recognized that the at least one salt of a hydroxycarboxylic acid is selected from the group consisting of at least one hydroxymonocarboxylic acid salt, at least one hydroxydicarboxylic acid salt, a combination of at least one hydroxymonocarboxylic acid salt and at least one hydroxydicarboxylic acid salt, which may include a mixture of at least one glucarate salt, at least one gluconate salt, at least one 5-keto-gluconate salt, at least one tartrate salt, at least one tartronate salt, and at least one glycolate salt. In one embodiment, the mixture of hydroxycarboxylic acids may include about 30% to about 75% of the at least one glucarate salt, about 0% to about 20% of the at least one gluconate salt, about 0% to about 10% of the at least one 5-keto-gluconate salt, about 0% to about 10% of the at least one tartrate salt, about 0% to about 10% of the at least one tartronate salt, and about 0% to about 10% of the at least one glycolate salt. The mixture includes about 40% to about 60% of at least one glucarate salt, about 5% to about 15% of at least one gluconate salt, about 3% to about 9% of at least one 5-keto-gluconate salt, about 5% to about 10% of at least one tartrate salt, about 5% to about 10% of at least one tartronate salt, and about 1% to about 5% of at least one glycolate salt. In another embodiment, the mixture comprises about 45% to about 55% of the at least one glucarate salt, about 10% to about 15% of the at least one gluconate salt, about 4% to about 6% of the at least one 5-keto-gluconate salt, about 5% to about 7% of the at least one tartrate salt, about 5% to about 7% of the at least one tartronate salt, and about 3% to about 5% of the at least one glycolate salt. In another embodiment, the mixture comprises about 50% of the at least one glucarate salt, about 15% of the at least one gluconate salt, about 4% of the at least one 5-keto-gluconate salt, about 6% of the at least one tartrate salt, about 6% of the at least one tartronate salt, and about 5% of the at least one glycolate salt.

The calcium sequestering composition typically comprises from about 25% to about 75% by weight of the at least one salt of hydroxycarboxylic acid, from about 1% to about 50% by weight of the at least one citric acid salt, and from about 1% to about 50% by weight of the at least one suitable oxoacid anion salt. In one embodiment, the composition comprises from about 40% to about 60% by weight of the at least one salt of hydroxycarboxylic acid, from about 10% to about 35% by weight of the at least one citric acid salt, and from about 10% to about 35% by weight of the at least one suitable oxoacid anion salt. In a further embodiment, the composition comprises about 50% by weight of the at least one salt of hydroxycarboxylic acid, about 20% by weight of the at least one suitable oxoacid anion salt, and about 30% by weight of the at least one citric acid salt.

Suitable salts of oxoacid anions include sodium and potassium salts of borates, aluminates, stannates, germanates, molybdates, antimonates or mixtures thereof. It is further recognized that the aluminum salt of the at least one calcium sequestering composition can comprise sodium aluminate, aluminum chloride, or mixtures thereof. The at least one citrate salt may comprise sodium citrate, potassium citrate, calcium citrate, magnesium citrate, or mixtures thereof.

In another aspect, the present invention provides a method of sequestering calcium ions from a medium comprising administering a composition having a combination of: at least one salt of a hydroxycarboxylic acid selected from the group consisting of at least one salt of a hydroxymonocarboxylic acid, at least one salt of a hydroxydicarboxylic acid, and a combination of at least one salt of a hydroxymonocarboxylic acid and at least one salt of a hydroxydicarboxylic acid, at least one suitable salt of an oxoacid anion, and at least one salt of a citric acid. The at least one salt of a hydroxycarboxylic acid may include a salt of glucaric acid, a salt of gluconic acid, a salt of 5-keto-gluconic acid, a salt of tartaric acid, a salt of tartronic acid, a salt of glycolic acid, a salt of glyceric acid, a salt of xylaric acid, a salt of galactaric acid, or mixtures thereof. Additionally, the at least one salt of a hydroxycarboxylic acid may include a mixture of at least one glucarate salt, at least one gluconate salt, at least one 5-keto-gluconate salt, at least one tartrate salt, at least one tartronate salt, and at least one glycolate salt. Suitable salts of oxoacid anions include sodium and potassium salts of borates, aluminates, stannates, germanates, molybdates, antimonates or mixtures thereof. Additionally, the at least one aluminum salt may include sodium aluminate, aluminum chloride, or mixtures thereof. The at least one citrate salt may comprise sodium citrate, potassium citrate, calcium citrate, magnesium citrate, or mixtures thereof.

In another aspect, the present invention provides a detergent composition comprising a calcium sequestering composition comprising at least one salt of a hydroxycarboxylic acid, at least one salt of an oxoacid anion, and at least one salt of citric acid selected from the group consisting of at least one hydroxymonocarboxylic acid salt, at least one hydroxydicarboxylic acid salt, and a combination of at least one hydroxymonocarboxylic acid salt and at least one hydroxydicarboxylic acid salt. The detergent composition may further comprise one or more additional functional materials such as, for example, rinse aids, bleaches, disinfectants/antimicrobials, activators, detergent adjuncts or fillers, pH buffers, fabric relaxants, fabric softeners, soil release agents, anti-foam agents, anti-redeposition agents, stabilizers, dispersants, optical brighteners, antistatic agents, anti-wrinkle agents, odor capture agents, fiber protectants, color protection agents, dyes/odorants, UV protectants, anti-pilling agents, water repellents, hardeners/solubility modifiers, glass and metal corrosion inhibitors, enzymes, detergents, oxidizing agents, solvents and insect repellents.

Detailed description of the invention

The present invention describes novel calcium sequestering compositions comprising a mixture of a salt of a hydroxycarboxylic acid, at least one salt of a suitable oxoacid anion, and at least one salt of citric acid. Hydroxycarboxylic acids are compounds that contain one or more hydroxyl groups and one or more carboxylic acid functionalities. A hydroxymonocarboxylic acid can be defined as a compound having only one carboxyl group. A hydroxydicarboxylic acid can be defined as a compound having two carboxyl groups. The hydroxyl groups of these compounds are capable of forming metal ion chelate complexes when combined with suitable oxoacid anion salts. In contrast to hydroxycarboxylic acids, which typically form water-insoluble salts with many metal ions alone, it has been shown that these complexes can form stable, water-soluble complexes with metal ions such as calcium and magnesium, thereby providing metal chelating properties.

As used herein, the term "hydroxycarboxylic acid" can be generally considered to be any oxidized derivative of a carbohydrate or other polyol, and should not be construed to include primarily hydroxymonocarboxylic acids and hydroxydicarboxylic acids. Mixtures of hydroxycarboxylic acids suitable for use in the present invention may also be conveniently prepared by oxidation of carbohydrate or other polyol compounds. The oxidation of carbohydrate compounds can be carried out by a variety of known methods including oxidation with nitric acid, oxidation with nitrogen dioxide, oxidation with air or oxygen over metal catalysts and oxidation with tetraalkylnitroxyl compounds such as TEMPO. The term polyol is generally defined as any organic compound bearing two or more alcoholic hydroxyl groups. Suitable carbohydrates or polyols for oxidation include: simple aldoses and ketoses, such as glucose, xylose or fructose; simple polyols such as glycerol, sorbitol or mannitol; reducing disaccharides such as maltose, lactose or cellobiose; reducing oligosaccharides, such as maltotriose, maltotetraose or maltotetralose; non-reducing carbohydrates, such as sucrose, trehalose and stachyose; mixtures of mono-and oligosaccharides (which may include disaccharides); glucose syrups having different glucose equivalent values; polysaccharides such as, but not limited to, starch, cellulose, arabinogalactans, xylans, mannans, fructans, hemicelluloses; mixtures of carbohydrates and other polyols including one or more of the carbohydrates or polyols listed above. Specific examples of hydroxycarboxylic acids that may be used in the present invention include, but are not limited to, glucaric acid, xylaric acid, galactaric acid, gluconic acid, tartaric acid, tartronic acid, glycolic acid, glyceric acid, and combinations thereof. In one embodiment, the hydroxycarboxylic acids include glucaric acid, xylaric acid, and galactaric acid. In addition, it will be understood by those skilled in the art that the hydroxycarboxylic acids of the present invention include all conceivable stereoisomers, including diastereomers and enantiomers in substantially pure form and mixed in any mixing ratio, including racemates of hydroxycarboxylic acids.

The calcium sequestering compositions of the present invention include the salt forms of the hydroxycarboxylic acids discussed herein. It will be appreciated by those skilled in the art that salts are generally compounds resulting from the neutralization of acids and bases. Any oxidized derivative of a carbohydrate or other polyol may be incorporated into the present invention in its salt form. Non-limiting examples of hydroxycarboxylic acid salts include: disodium glucarate, potassium sodium glucarate, dipotassium glucarate, dilithium glucarate, sodium lithium glucarate, potassium lithium glucarate, zinc glucarate, diammonium glucarate, disodium xylarate, potassium sodium xylarate, dipotassium xylarate, dilithium xylarate, sodium lithium xylarate, potassium lithium xylarate, zinc xylarate, ammonium xylarate, sodium gluconate, potassium gluconate, lithium gluconate, zinc gluconate, ammonium gluconate, disodium galactarate, potassium sodium galactarate, dipotassium galactarate, dilithium galactarate, sodium lithium galactarate, potassium lithium galactarate, diammonium galactarate, disodium tartrate, potassium sodium tartrate, dipotassium tartrate, dilithium tartrate, sodium lithium tartrate, potassium lithium tartrate, zinc tartrate, diammonium tartrate, disodium tartronate, potassium sodium tartronate, potassium lithium tartrate, Dipotassium tartronate, dilithium tartronate, sodium lithium tartronate, potassium lithium tartronate, zinc tartronate, diammonium tartronate, sodium glycolate, potassium glycolate, lithium glycolate, zinc glycolate, ammonium glycolate, sodium glycerate, potassium glycerate, lithium glycerate, zinc glycerate, ammonium glycerate, and combinations of the foregoing. In another embodiment, hydroxycarboxylic acids may include, but are not limited to, disodium glucarate, sodium potassium glucarate, dipotassium glucarate, zinc glucarate, disodium xylarate, sodium potassium xylarate, dipotassium xylarate, zinc xylarate, disodium galactarate, sodium potassium galactarate, dipotassium galactarate, zinc galactarate, ammonium dimoxylanate, and combinations thereof.

As used herein, the term "oxoacid anion salt" is defined as any water-soluble salt form of an acid containing at least one oxygen atom. Salts of oxoacid anions may include, but are not limited to, borates, aluminates, stannates, germanates, molybdates, antimonates, and combinations thereof. In one embodiment, the at least one suitable oxoacid anion salt comprises sodium borate, potassium borate, disodium octaborate, sodium metaborate, sodium molybdate, potassium molybdate, aluminum sulfate, aluminum nitrate, aluminum chloride, aluminum formate, sodium aluminate, aluminum bromide, aluminum fluoride, aluminum hydroxide, aluminum phosphate, aluminum iodide, aluminum sulfate, sodium stannate, potassium stannate, sodium germanate, potassium germanate, sodium antimonite, potassium antimonite, and combinations thereof. In another embodiment, the aluminum salt comprises sodium aluminate and aluminum chloride.

As used herein, the term "citrate salt" is defined to include any salt form of citric acid known in the art. Typically, citrate salts are water soluble. Citrate salts are known to have metal chelating properties and, therefore, any citrate salt known in the art may be included in the compositions of the present invention. Suitable examples of citrate salts may include, but are not limited to, sodium citrate, potassium citrate, calcium citrate, magnesium citrate, ammonium citrate, and combinations thereof.

The calcium sequestering composition typically comprises from about 25% to about 75% by weight of at least one salt of a hydroxymonocarboxylic acid or hydroxydicarboxylic acid, from about 1% to about 50% by weight of at least one suitable oxoacid anion salt, and from about 1% to about 50% by weight of at least one citric acid salt. The specific percentages of the at least one hydroxycarboxylic acid, the at least one suitable oxoacid anion salt, and the at least one citric acid salt may vary depending on the desired characteristics of the composition. Generally, compositions having different concentrations of one or more hydroxycarboxylic acid salts, suitable oxoacid anion salts, and suitable citric acid salts have different abilities to bind metal ions depending on the pH of the medium in which the metal ions are bound. In view of this, the relative percentages of hydroxycarboxylic acid, suitable oxoacid anion salts, and suitable citrate salts may vary depending on the pH of the desired medium to be treated with the calcium chelating agent. The calcium sequestering composition typically comprises from about 25% to about 75% by weight of the at least one salt of hydroxycarboxylic acid, from about 1% to about 50% by weight of the at least one suitable oxoacid anion salt, and from about 1% to about 50% by weight of the at least one citric acid salt. In one embodiment, the composition comprises from about 40% to about 60% by weight of the at least one salt of hydroxycarboxylic acid, from about 10% to about 35% by weight of the at least one suitable oxoacid anion salt, and from about 10% to about 35% by weight of the at least one citric acid salt. In one embodiment, the composition comprises from about 45% to about 55% by weight of the at least one salt of hydroxycarboxylic acid, from about 15% to about 25% by weight of the at least one suitable oxoacid anion salt, and from about 15% to about 35% by weight of the at least one citric acid salt. In other embodiments, the composition comprises about 55% by weight of the at least one salt of hydroxycarboxylic acid, about 25% by weight of the at least one suitable oxoacid anion salt, and about 35% by weight of the at least one citric acid salt. In other embodiments, the composition comprises about 50% by weight of the at least one salt of hydroxycarboxylic acid, about 20% by weight of the at least one suitable oxoacid anion salt, and about 30% by weight of the at least one citric acid salt. In other embodiments, the composition comprises about 45% by weight of the at least one salt of hydroxycarboxylic acid, about 15% by weight of the at least one suitable oxoacid anion salt, and about 25% by weight of the at least one citric acid salt.

It will be understood by those skilled in the art that other additives may be included in the calcium sequestering compositions of the present invention so long as the additives do not adversely affect the ability of the calcium sequestering composition to sequester metal ions. Typical additives may include, but are not limited to, organic detergents, cleaners, rinse aids, bleaches, disinfectants/antimicrobials, activators, detergent builders or fillers, defoamers, anti-redeposition agents, optical brighteners, dyes/odorants, additional hardening/solubility modifiers, surfactants or any other natural or synthetic agent capable of modifying the properties of the calcium sequestering composition.

The calcium sequestering compositions of the present invention may be used in any application where it is desirable to sequester or capture metal ions. Suitable examples of industrial applications in which the compositions of the present invention may be utilized include, but are not limited to, detergent builders, detergents for industrial water treatment purposes and as renewable replacements for ethylenediaminetetraacetic acid (EDTA), nitrilotriacetic acid (NTA), Sodium Tripolyphosphate (STPP), and other commonly used chelants.

The hydroxycarboxylic acids of the present invention may be produced according to any method currently known in the art. The currently employed commercial processes for preparing common hydroxycarboxylic acids or salts thereof are primarily biologically induced transformations or fermentations, for example in the preparation of tartaric acid (U.S. Pat. No. 2,314,831) and gluconic acid (U.S. Pat. No. 5,017,485). Chemical methods for oxidation also exist, although they are not as popular as in commercial production. Some chemical oxidation processes suitable for polyol feedstocks include: oxidation with oxygen over a metal catalyst (U.S. patent No. 2,472,168) and oxidation mediated with a tetraalkylnitroxyl compound such as TEMPO (U.S. patent No. 6,498,269). Other methods employ nitric acid as the oxidizing agent in aqueous solution and have been described (Kiely, U.S. Pat. No. 7,692,041). The skilled person will appreciate that any of the methods described herein, as well as any combination of these methods, may be used to obtain the hydroxycarboxylic acid.

The oxidation of a polyol feedstock such as glucose typically produces a mixture of oxidation products. For example, oxidation of glucose by any of the methods listed above will produce glucaric acid as well as other oxidation products, including gluconic acid, glucaric acid, tartaric acid, tartronic acid, and glycolic acid, all of which are hydroxycarboxylic acids, and are within the scope of the invention. One ubiquitous hydroxycarboxylic acid produced by these oxidation processes includes glucaric acid. It is known in the art that glucaric acid product in salt form can be selectively isolated from a mixture of other hydroxycarboxylic acids by titration with a basic compound such as potassium hydroxide and subsequently used as the hydroxycarboxylic acid component of the calcium sequestering compositions of the present invention. Such compositions prepared by oxidation processes comprising glucaric acid as the hydroxycarboxylic acid, separated from the remaining hydroxycarboxylic acids, may be referred to as "purified" glucaric acid compositions. Alternatively, a mixture of hydroxycarboxylic acids produced by oxidizing glucose may be used as the hydroxycarboxylic acid component of the composition of the present invention without isolation of the glucaric acid component. Such mixtures are referred to as "unpurified" glucaric acid compositions. Thus, the unrefined glucaric acid composition comprises a mixture of one or more hydroxycarboxylic acids produced by oxidation of a donor material, and may include gluconic acid, 5-keto-gluconic acid, glucaric acid, tartaric acid, tartronic acid, and glycolic acid. The use of an unpurified glucaric acid mixture as the hydroxycarboxylic acid component of the present compositions provides a number of advantages over the art, including cost-effectiveness due to a reduced number of processing steps and increased product yield.

The invention also includes methods of sequestering calcium from different media having different pH levels. The skilled artisan will appreciate that any medium, including but not limited to liquids, gels, semisolids, and solids, can be treated with the calcium sequestering compositions of the present invention. In general, the compositions of the present invention are effective due to the fact that at least one hydroxycarboxylic acid and at least one oxoacid anion salt can form a complex suitable for chelating metal ions. The formation of the hydroxycarboxylic acid salt/oxoacid anion complex is dependent on pH so that the complex can form more readily with increasing pH, and calcium sequestration generally improves with increasing pH. In addition, glucaric acid is believed to provide the best choice for chelating calcium ions due to the structural characteristics of the compound. In addition, citrate can chelate metal ions from a variety of mediators; however, the chelating ability of citric acid in the presence of oxoacid anions cannot be improved as observed with glucaric acid, probably due to the fact that it has only one hydroxyl group and cannot form diester complexes. Surprisingly, it has been found that a combination of one or more salts of hydroxycarboxylic acids, one or more salts of suitable oxoacid anions, and one or more salts of citric acid can synergistically bind metal ions. In particular, the calcium sequestering compositions of the present invention can bind calcium ions to a degree that is significantly greater than would be predicted if the sequestering capacity of the hydroxycarboxylate/aluminate and the sequestering capacity of the citrate were additive only.

It should be noted that the calcium sequestering compositions of the present invention can be used to sequester calcium ions from media having a variety of pH levels. Generally, the composition can be used to sequester calcium ions from a medium having a pH of about 6 to about 14. In one embodiment, the present invention provides a method of sequestering calcium ions from a medium having a pH of about 8.5 to about 11.5, comprising applying a composition comprising a combination of: at least one salt of a hydroxycarboxylic acid, at least one suitable oxoacid anion salt, and at least one suitable citric acid salt. The at least one salt of a hydroxycarboxylic acid can include a salt of glucaric acid, a salt of gluconic acid, a salt of 5-keto-gluconic acid, a salt of tartaric acid, a salt of tartronic acid, a salt of glycolic acid, a salt of xylaric acid, a salt of galactaric acid, and combinations thereof. In one embodiment, the at least one salt of a hydroxycarboxylic acid may include a mixture of at least one glucarate salt, at least one gluconate salt, at least one 5-keto-gluconate salt, at least one tartrate salt, at least one glycolate salt, and at least one tartronate salt.

In one embodiment, the mixture of hydroxycarboxylic acids may include about 30% to about 75% of the at least one glucarate salt, about 0% to about 20% of the at least one gluconate salt, about 0% to about 10% of the at least one 5-keto-gluconate salt, about 0% to about 10% of the at least one tartrate salt, about 0% to about 10% of the at least one tartronate salt, and about 0% to about 10% of the at least one glycolate salt. In another embodiment, the mixture comprises about 40% to about 60% of the at least one glucarate salt, about 5% to about 15% of the at least one gluconate salt, about 3% to about 9% of the at least one 5-keto-gluconate salt, about 5% to about 10% of the at least one tartrate salt, about 5% to about 10% of the at least one tartronate salt, and about 1% to about 5% of the at least one glycolate salt. In another embodiment, the mixture comprises about 45% to about 55% of the at least one glucarate salt, about 10% to about 15% of the at least one gluconate salt, about 4% to about 6% of the at least one 5-keto-gluconate salt, about 5% to about 7% of the at least one tartrate salt, about 5% to about 7% of the at least one tartronate salt, and about 3% to about 5% of the at least one glycolate salt. In another embodiment, the mixture comprises about 50% of the at least one glucarate salt, about 15% of the at least one gluconate salt, about 4% of the at least one 5-keto-gluconate salt, about 6% of the at least one tartrate salt, about 6% of the at least one tartronate salt, and about 5% of the at least one glycolate salt. It should be noted that all percentages of the salt of hydroxycarboxylic acid are based on the total weight of the hydroxycarboxylic acid salt components in the calcium sequestering composition, and do not include additional weights of suitable oxoacid anion salts and citrate salts.

Generally, a method of sequestering calcium ions from a medium having a pH of about 6 to about 14 comprises using a calcium sequestering composition comprising about 25% to about 75% by weight of at least one salt of a hydroxycarboxylic acid, about 1% to about 50% by weight of at least one suitable oxoacid anion salt, and about 1% to about 50% by weight of at least one citric acid salt. In one embodiment, the composition comprises from about 40% to about 60% by weight of the at least one salt of hydroxycarboxylic acid, from about 10% to about 35% by weight of the at least one suitable oxoacid anion salt, and from about 10% to about 40% by weight of the at least one citric acid. In further embodiments, the composition comprises from about 45% to about 55% by weight of the at least one salt of hydroxycarboxylic acid, from about 15% to about 25% by weight of the at least one suitable oxoacid anion salt, and from about 25% to about 35% by weight of the at least one citric acid. In other embodiments, the composition comprises about 50% by weight of the at least one salt of hydroxycarboxylic acid, about 20% by weight of the at least one suitable oxoacid anion salt, and about 30% by weight of the at least one citric acid salt.

The present invention also includes detergent compositions comprising the calcium sequestering compositions of the present invention, and as described above. The detergent composition may contain one or more functional materials which provide the detergent composition with the desired properties and functions. For the purposes of this application, the term "functional material" includes materials that, when dispersed or dissolved in a use solution, such as an aqueous solution, and/or a concentrated solution, can provide advantageous properties in a particular application. Examples of such functional materials include, but are not limited to: organic detergents, cleaners; a rinse aid; a bleaching agent; disinfectants/antimicrobials; an activator; detergent builders or fillers; defoaming agents, anti-redeposition agents; an optical brightener; dyes/odorants; secondary hardeners/solubility modifiers; insecticides, etc., for pest control applications, or a variety of other functional materials, depending on the desired characteristics and/or functionality of the detergent composition.

The functional material may be a rinse aid composition, such as a rinse aid formulation containing a wetting agent or a sheeting agent in combination with other optional ingredients in a solid composition made using a binder. The rinse aid component can reduce the surface tension of the rinse water to facilitate the sheeting action and/or to prevent spotting or streaking caused by beaded water after rinsing is complete, such as during a ware wash. Examples of covering agents (sheeting agents) include, but are not limited to: polyether compounds prepared from ethylene oxide, propylene oxide or mixtures of the homopolymer or block copolymer or mixed copolymer structures. Such polyether compounds are known as polyethylene oxide polymers, polyoxyalkylene polymers or polyolefin glycol polymers. Such capping agents require regions of relative hydrophobicity and regions of relative hydrophilicity to provide surfactant properties to the molecule.

The functional material may be a bleaching agent that brightens or whitens the substrate and may include a material that releases, for example, Cl under conditions typically encountered during rinsing₂、Br₂-OCl-and/or-OBr-, etc. Examples of suitable bleaching agents include, but are not limited to: chlorine-containing compounds, such as chlorine, hypochlorite or chloramine. Examples of suitable halogen-releasing compounds include, but are not limited to: alkali metal dichloroisocyanurates, alkali metal hypochlorites, monochloramine and dichloramine. Encapsulated chlorine sources may also be used to enhance incorporationStability of chlorine source in the material. Bleaching agents may also include preparations that contain or act as a source of active oxygen. The active oxygen compound serves to provide a source of active oxygen and may release active oxygen in an aqueous solution. The active oxygen compound may be inorganic, organic or a mixture thereof. Examples of suitable active oxygen compounds include, but are not limited to: peroxy compounds, peroxy compound adducts, hydrogen peroxide, perborates, sodium carbonate peroxyhydrate, phosphate peroxyhydrate, potassium hydrogen peroxymonosulfate, and sodium perborate monohydrate and sodium perborate tetrahydrate, with and without activators such as tetraacetylethylenediamine.

The functional material may be a sanitizer (or an antimicrobial). Sanitizers, also known as antimicrobial agents, are chemical compositions that can be used to prevent microbial contamination and deterioration of material systems, surfaces, and the like. Typically, these materials fall into specific classes, including phenolics, halogen compounds, quaternary ammonium compounds, metal derivatives, amines, alkanolamines, nitro derivatives, anilides, organosulfur and thiazepine compounds, and hybrid compounds.

The antimicrobial agent applied, depending on the chemical composition and concentration, may simply limit further spread of many microorganisms or may destroy all or part of the microbial community. The terms "microorganisms" and "microorganisms" generally refer primarily to microorganisms of the bacterial, viral, yeast, spore and fungal types. In use, the antimicrobial agent is typically formulated as a solid functional material, which optionally, for example, when diluted and dispersed with an aqueous stream, can form an aqueous disinfectant or sanitizer composition that can be contacted with a variety of surfaces to produce a growth-inhibiting or killing portion of the microbial population. A 3 log reduction in microbial population results in a disinfectant composition. Antimicrobial agents may be encapsulated, for example, to increase their stability.

Examples of suitable antimicrobial agents include, but are not limited to, phenolic antimicrobial agents, such as pentachlorophenol; o-phenylphenol; chloro-p-phenylphenol; p-chloro-m-xylenol; quaternary ammonium compounds, such as alkyl dimethyl benzyl ammonium chloride; alkyl dimethyl ethyl benzyl ammonium chloride; octyl decyl dimethyl ammonium chloride; dioctyl dimethyl ammonium chloride; and didecyl dimethyl ammonium chloride. Examples of suitable antimicrobial-containing halogens include, but are not limited to: sodium trichloroisocyanurate, sodium dichloroisocyanate (anhydrous or dihydrate), iodine-poly (vinylpyrrolidone) complexes, bromides such as 2-bromo-2-nitropropane-l, 3-diol, and quaternary (quaternary) antimicrobials such as benzalkonium chloride, didecyldimethylammonium chloride, diiodocholine chloride, and tetramethylphosphonium tribromide. Other antimicrobial compositions, such as hexahydro-l, 3, 5-tris (2-hydroxyethyl) -s-triazine, dithiocarbamates such as sodium dimethyldithiocarbamate, and a variety of other materials are known in the art for their antimicrobial properties.

It should also be understood that active oxygen compounds, such as those discussed in the bleach section above, may also be used as antimicrobial agents, and may even provide disinfecting activity. Indeed, in some embodiments, the ability of the active oxygen compound to act as an antimicrobial agent reduces the need for additional antimicrobial agents within the composition. For example, percarbonate compositions have been shown to provide excellent antimicrobial activity.

In some embodiments, the antimicrobial or bleaching activity of the detergent composition may be enhanced by the addition of such materials, which may react with active oxygen to form an activated component when the detergent composition is used. For example, in some embodiments, a peracid or a peracid salt is formed. For example, in some embodiments, tetraacetylethylenediamine may be included in the detergent composition to react with active oxygen and form a peracid or persalt that acts as an antimicrobial agent. Other examples of active oxygen activators include transition metals and their compounds, compounds containing a carboxyl, nitrile, or ester moiety, or other such compounds known in the art. In embodiments, the activator comprises tetraacetylethylenediamine; a transition metal; a compound comprising a carboxyl, nitrile, amine or ester moiety; or mixtures of the above. In some embodiments, an activator of an active oxygen compound is combined with active oxygen to form an antimicrobial agent.

The functional material may be a detergent filler, which does not necessarily function as a detergent per se, but may cooperate with a detergent to enhance the overall cleaning ability of the composition. Examples of suitable fillers include, but are not limited to: sodium sulfate, sodium chloride, starch, saccharides and C₁-C₁₀Alkylene glycols, such as propylene glycol.

The detergent composition may be formulated for use in rendering the wash water to have a desired pH during aqueous operations, such as in water washing operations. For example, the composition may be formulated to provide a pre-preg composition such that, during use in a water wash operation, the wash water has a pH of about 6.5 to about 12, and in some embodiments, a pH of about 7.5 to about 11. In some embodiments, the liquid product formulation has a pH (10% dilution) of about 7.5 to about 11.0, and in some embodiments, a pH of about 7.5 to about 9.0.

For example, an acid treatment agent may be added to the detergent composition so that the pH of the fabric approximately matches the appropriate treatment pH. The acid treatment agent is a weak acid that serves to neutralize residual alkaline materials and reduce the pH of the fabric so that the fabric does not irritate the skin when the garment comes into contact with the skin. Examples of suitable acid treatment agents include, but are not limited to: phosphoric acid, formic acid, acetic acid, hydrofluorosilicic acid, saturated fatty acids, dicarboxylic acids, tricarboxylic acids, and any combination thereof. Examples of saturated fatty acids include, but are not limited to: saturated fatty acids having 10 or more carbon atoms, such as palmitic acid, stearic acid and arachidic acid (C20). Examples of dicarboxylic acids include, but are not limited to: oxalic acid, tartaric acid, glutaric acid, succinic acid, adipic acid, and sulfamic acid. Examples of tricarboxylic acids include, but are not limited to: citric acid and tricarballylic acids.

The functional material may be a fabric relaxant added to the detergent composition to increase the slippery feel of the fabric surface. Fabric softeners may be added to the detergent composition to increase the softness of the fabric surface.

The functional material may be a soil release agent that may be provided to coat the fibers of the fabric to reduce the tendency of soil to adhere to the fibers.

The functional material may be an antifoaming agent for reducing bubble stability. Examples of suitable anti-foaming agents include, but are not limited to: silicone compounds such as silica dispersed in polydimethylsiloxane, fatty amides, hydrocarbon waxes, fatty acids, fatty acid esters, fatty alcohols, fatty acid soaps, ethoxylates, mineral oils, polyethylene glycol esters, and alkyl phosphate esters such as monostearyl phosphate.

The functional material may be an anti-redeposition agent that can promote the maintenance of soil in suspension in the rinse solution and prevent the redeposition of the removed soil onto the substrate being cleaned. Examples of suitable anti-redeposition agents include, but are not limited to: fatty acid amides, fluorocarbon surfactants, complex phosphate esters, polyacrylates, styrene maleic anhydride copolymers and cellulose derivatives such as hydroxyethyl cellulose, hydroxypropyl cellulose.

The functional material may be a stabilizer. Examples of suitable stabilizers include, but are not limited to: borate, calcium/magnesium ions, propylene glycol, and mixtures thereof.

The functional material may be a dispersant. Examples of suitable dispersants that can be used in the detergent composition include, but are not limited to: maleic acid/olefin copolymers, polyacrylic acid and mixtures thereof.

The functional material may be an optical brightener, also known as fluorescent brightener or optical brightener, and may provide optical compensation for yellow color disposed in the fabric substrate.

Fluorescent compounds belonging to the family of optical brighteners are generally aromatic or aromatic heterocyclic materials which often contain fused ring systems. These compounds are characterized by the presence of a continuous chain of conjugated double bonds associated with the aromatic ring. The number of such conjugated double bonds depends on the substituents and the planarity of the fluorescent portion of the molecule. Most brightener compounds are derivatives of stilbenes or 4,4' -diaminostilbenes, biphenyl, five-membered heterocycles (triazoles, oxazoles, imidazoles, etc.) or six-membered heterocycles (naphthamides, triazines, etc.). The choice of whitening agent for use in the composition will depend on a number of factors such as the type of composition, the nature of the other components present in the composition, the temperature of the wash water, the degree of agitation and the ratio of material washed to the size of the container. Brightener selection also depends on the type of material to be washed, e.g., cotton, synthetic, etc. Because most laundry detergent products are used to rinse a wide variety of fabrics, the detergent composition may contain a mixture of whitening agents that are effective on a wide variety of fabrics. Preferably, the individual components of such brightener mixtures are compatible.

Examples of suitable optical brighteners are commercially available and are understood by those skilled in the art. At least some commercial whitening agents may be divided into subgroups, including but not limited to: stilbenes, pyrazolines, carboxylic acids, methinecyanines, dibenzothiophene-5, 5-dioxides, azoles, derivatives of 5-and 6-membered ring heterocycles, and other miscellaneous agents. Examples of particularly suitable optical brighteners include, but are not limited to: diphenylethylene bisdiphenylsulfonic acid sodium salt and cyanuric chloride/diaminostilbene disulfonic acid sodium salt.

Suitable stilbene derivatives include, but are not limited to: di (triazinyl) amino-stilbene derivatives, stilbene diamido derivatives, stilbene triazole derivatives, stilbene oxadiazole derivatives, stilbene oxazole derivatives and stilbene styryl derivatives.

The functional material may be an antistatic agent such as those materials commonly used in the laundry drying industry to provide antistatic properties. The antistatic agent can produce a percent static reduction of at least about 50% when compared to untreated fabric. The static reduction percentage may be greater than 70% and it may be greater than 80%. Examples of antistatic agents include, but are not limited to, formulations containing quaternary groups.

The functional material may be an anti-wrinkle agent to provide anti-wrinkle properties. Examples of suitable formulations for anti-wrinkle include, but are not limited to: a siloxane or silica gel comprising a compound and a quaternary ammonium compound. Particularly suitable examples of anti-wrinkle agents include, but are not limited to: polydimethyl siloxane diquaternary ammonium, silicone copolyol fatty quaternary ammonium, and polydimethyl siloxane with polyoxyalkylene.

The functional material may be an odor capture agent. In general, odor capture agents are believed to function by capturing or blocking certain molecules that provide odor. Examples of suitable odor capture agents include, but are not limited to: cyclodextrin and zinc ricinoleate.

The functional material may be a fiber protectant that coats the fibers of the fabric to reduce or prevent degradation and/or degradation of the fibers. Examples of fiber protectants include, but are not limited to, fiber polymers.

The functional material may be a color fixative for coating the fibers of the fabric to reduce the tendency of the dye to escape the fabric into the water. Examples of suitable color fixatives include, but are not limited to: quaternary ammonium compounds and surfactants.

Various dyes, odorants including perfumes, and other aesthetic enhancers may also be included in the detergent composition. Examples of suitable flavorants or aromas include, but are not limited to: terpenes such as citronellol, aldehydes such as amyl cinnamaldehyde, jasmine such as cis-jasmine or jasmine pyran (jasmal), and vanillin.

The functional material may be a UV protectant that provides added UV protection to the fabric. In garments, it is believed that by applying UV protection agents to the garment, it is possible to reduce the adverse effect of ultraviolet radiation provided under the garment on the skin. As the weight of the garment becomes lighter, UV light has a greater tendency to penetrate the garment, and the skin underneath the garment may be sunburned.

The functional material may be an anti-pilling agent acting on the part of the fibres protruding or leaving the fibres. The anti-pilling agent may be used as an enzyme such as cellulase.

The functional material may be a water repellent that may be applied to the fabric to improve water repellency. Examples of suitable water repellents include, but are not limited to: a perfluoroacrylate copolymer, a hydrocarbon wax, and a polysiloxane.

The functional material may be a hardener. Examples of suitable hardeners include, but are not limited to: such as stearylmonoethanolamide or lauryldiethanolamide, amides of alkylamides, solid polyethylene glycols, solid EO/PO block copolymers, starches made water-soluble by acid or base treatment procedures, and different inorganics that impart curing properties to heated compositions by cooling. Such compounds may also modify the solubility of the composition in aqueous media during use so that the detergent and/or other active ingredient may be dispersed from the solid composition over an extended period of time.

The functional material may be a metal corrosion inhibitor present in an amount of up to about 30%, up to about 6%, and up to about 2%. The corrosion inhibitor is included in the detergent composition in an amount sufficient to provide a use solution exhibiting a glass corrosion and/or etch rate less than the glass corrosion and/or etch rate of an otherwise identical use solution except for the absence of the corrosion inhibitor. Examples of suitable corrosion inhibitors include, but are not limited to: an alkali metal silicate or a hydrate thereof.

An effective amount of an alkali metal silicate or hydrate thereof can be used in the compositions and methods of the present invention to form stable solid detergent compositions having metal protection capabilities. Silicates useful in the compositions of the present invention are those conventionally used in solid detergent formulations. For example, typical alkali metal silicates are those which are anhydrous or preferably contain water of hydration (about 5% to about 25%, especially about 15% to about 20% water of hydration), in powder, granular or granular form. These silicates are preferably sodium silicate and have Na of about 1:1 to about 1:5, respectively₂O:SiO₂And typically contains water available in an amount of about 5% to about 25%. Typically, the silicate has a Na of about 1:1 to about 1:3.75₂O:SiO₂A ratio, specifically from about 1:1.5 to about 1:3.75, and most specifically from about 1:1.5 to about 1: 2.5. Silicate utensilHas about 1:2 Na₂O:SiO₂Ratios, and from about 16% to about 22% water of hydration are most preferred. For example, such silicates are available from PQ Corporation, Valley Forge, Pa, where GD silicate is available in powder form and Britesil H-20 is available in granular form. These ratios can be obtained using a combination of monosilicate compositions or silicates, based on the combined results of the preferred ratios. It has been found that a preferred ratio of hydration of the silicate, Na, of about 1:1.5 to about 1:2.5₂O:SiO₂In contrast, excellent metal protection can be provided and solid detergents can be formed quickly.

Silicates may be included in detergent compositions to provide metal protection, but are otherwise known to provide alkalinity and provide additional functionality as anti-redeposition agents. Exemplary silicates include, but are not limited to: sodium silicate and potassium silicate. Silicate is not present but can provide a detergent composition when present, and is included in an amount that provides the desired metal protection. The concentrate may comprise silicate in an amount of at least about 1%, at least about 5%, at least about 10%, and at least about 15%. Additionally, in order to provide sufficient room for the other components in the concentrate, the silicate component may be provided at a level of less than about 35%, less than about 25%, less than about 20%, and less than about 15%.

The functional material may be an enzyme. Enzymes that may be included in the detergent composition include those that aid in the removal of starch and/or protein contamination. Exemplary types of enzymes include, but are not limited to: protease, alpha-amylase and mixtures thereof. Exemplary proteases that can be used include, but are not limited to: those derived from Bacillus licheniformis (Bacillus licheniformis), Bacillus lentus (Bacillus lentus), Bacillus alcalophilus (Bacillus alcalophilus) and Bacillus amyloliquefaciens (Bacillus amyloliquefaciens). Exemplary alpha-amylases include species derived from Bacillus subtilis, Bacillus amyloliquefaciens, and Bacillus licheniformis. The concentrate does not necessarily comprise an enzyme, but when the concentrate comprises an enzyme, the enzyme may be included in an amount that provides the desired enzyme activity when the detergent composition is provided as a use composition. Typical ranges for the enzyme in the concentrate include up to about 10%, up to about 5%, and up to about 1%.

The functional material may be a detergent. In one embodiment, the detergent comprises from about 0.25wt% to about 10wt% of the detergent composition. In some embodiments, the detergent composition comprises from about 2wt% to about 5 wt%. In other embodiments, the detergent comprises from about 0.5wt% to about 1.5wt% of the detergent composition. It is to be understood that all values and ranges between these values and ranges are encompassed by the present invention.

In some embodiments, an effective amount of a detergent is applied to industrial food processing equipment so that the scale on the equipment is substantially removed. In some embodiments, at least about 10% of the fouling is removed from the equipment. In other embodiments, at least about 25% of the scale is removed. In other embodiments, at least about 50% of the scale is removed. In some embodiments, about 90% of the scale is removed.

In some embodiments, an effective amount of a detergent is applied to industrial food processing equipment to substantially prevent the formation of scale on the equipment. In some embodiments, at least about 10% of fouling is prevented. In other embodiments, at least about 25% of fouling is prevented. In other embodiments, at least about 50% of fouling is prevented. In some embodiments, about 90% of fouling is prevented.

The functional material may be an oxidizing agent, such as a peroxide or a peroxyacid. Suitable components are oxidizing agents such as chlorites, bromine, bromates, bromine monochloride, iodine monochloride, iodates, permanganates, nitrates, nitric acid, borates, perborates, and gaseous oxidizing agents such as ozone, oxygen, chlorine dioxide, chlorine, sulfur dioxide, and derivatives of the above. Peroxide-containing and different percarboxylic peroxide compounds containing percarbonates are suitable.

Peroxycarboxylic acids (orPercarboxylic acids) generally have the formula R (CO)₃H)_nWherein, for example, R is alkyl, aralkyl, cycloalkyl, aryl, or heterocyclyl, and n is 1, 2, or 3, and is named by prefixing the parent acid with a peroxy acid. The R groups may be saturated or unsaturated and substituted or unsubstituted. The medium chain peroxycarboxylic acids (or percarboxylic acids) may have the formula R (CO)₃H)_nWherein R is C₅-C₁₁Alkyl radical, C₅-C₁₁Cycloalkyl radical, C₅-C₁₁Aralkyl radical, C₅-C₁₁Aryl or C₅-C₁₁A heterocyclic group; and n is 1, 2 or 3. The short chain fatty acids may be of the formula R (CO)₃H)_nWherein R is C₁-C₄And n is 1, 2 or 3.

Examples of suitable peroxycarboxylic acids include, but are not limited to: peroxyvaleric acid, peroxycaproic acid, peroxyheptanoic acid, peroxyoctanoic acid, peroxynonanoic acid, peroxyisononanoic acid, peroxydecanoic acid, peroxyundecanoic acid, peroxydodecanoic acid, peroxyascorbic acid, peroxyadipic acid, peroxycitric acid, peroxyheptanoic acid, peroxysuberic acid, mixtures thereof, and the like.

Examples of suitable branched peroxycarboxylic acids include, but are not limited to: peroxyisovaleric acid, peroxyisononanoic acid, peroxyisocaproic acid, peroxyisoheptanoic acid, peroxyisooctanoic acid, peroxyisononanoic acid, peroxyisodecanoic acid, peroxyisoundecanoic acid, peroxyisododecanoic acid, peroxypivalic acid, peroxyneohexanoic acid, peroxyneoheptanoic acid, peroxyneooctanoic acid, peroxyneononanoic acid, peroxyneodecanoic acid, peroxyneoundecanoic acid, peroxyneododecanoic acid, mixtures thereof, and the like.

Typical peroxygen compounds include hydrogen peroxide (H)₂O₂) Peracetic acid, peroctanoic acid, persulphate, perborate or percarbonate.

The amount of oxidizing agent, if present, in the detergent composition is up to about 40 wt%. Acceptable levels of oxidizing agent are up to about 10wt%, with up to about 5% being particularly suitable levels.

The functional material may be a solvent to enhance soil release properties or to adjust the viscosity of the final composition. Suitable solvents useful in removing hydrophobic soils include, but are not limited to: oxygenated solvents such as lower alkanols, lower alkyl ethers, glycols, aryl glycol ethers and lower alkyl glycol ethers. Examples of other solvents include, but are not limited to: methanol, ethanol, propanol, isopropanol and butanol, isobutanol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, mixed ethylene-propylene glycol ethers, ethylene glycol phenyl ethers and propylene glycol phenyl ethers. Substantially water-soluble glycol ether solvents include, but are not limited to: propylene glycol methyl ether, propylene glycol propyl ether, dipropylene glycol methyl ether, tripropylene glycol methyl ether, ethylene glycol butyl ether, diethylene glycol methyl ether, diethylene glycol butyl ether, ethylene glycol dimethyl ether, ethylene glycol propyl ether, diethylene glycol ethyl ether, triethylene glycol methyl ether, triethylene glycol ethyl ether, triethylene glycol butyl ether, and the like.

When a solvent is included in the detergent composition, the amount of solvent included can be up to about 25wt%, specifically up to about 15 wt%, and more specifically up to about 5 wt%.

The functional material may be an insecticide, such as a mosquito repellent. One example of a commercially available insecticide is DEET. In addition, the aqueous carrier solution may contain mold inhibitors to remove mold and anti-allergenic agents (allergicides) that reduce the likelihood of allergies being present on certain fabrics and/or provide pathogen protection.

A variety of other ingredients useful in providing a particular detergent composition formulated to include a desired performance or function may also be included. For example, the detergent composition may contain other active ingredients, cleaning enzymes, carriers, processing aids, solvents for liquid formulations or others.

Detergent compositions may be used, for example, in automotive care applications, warewashing applications, laundry applications, and food and beverage applications. Such applications include, but are not limited to: machine and hand ware washing, pre-soaking, laundry and fabric cleaning and destaining, carpet cleaning and destaining, vehicle cleaning and care applications, surface cleaning and destaining, kitchen and bathroom cleaning and destaining, floor cleaning and destaining, clean-in-place operations, general purpose cleaning and destaining, and industrial or household cleaners.

The compounds and methods of the present invention may be better understood by reference to the following examples, which are intended as an illustration of the invention and not as a limitation on the scope of the invention. Each example illustrates at least one method of preparing different intermediate compounds and further illustrates each intermediate used in the overall process. These are certain preferred embodiments, which are not intended to limit the scope of the invention. On the contrary, the invention covers all alternatives, modifications and equivalents, which may be included within the scope of the claims and routine experimentation.

Example 1: sequestering calcium from water

The calcium-chelating capacity of various compounds and mixtures was determined by an established turbidity titration protocol (Wilham, 1971). Specifically, the chelating agent (1.0g dry weight) was dissolved in deionized water to provide 50g total solution. After addition of 2% aqueous sodium oxalate (3mL), the pH was adjusted accordingly using dilute HCI or 1M sodium hydroxide solution. The test solution was titrated with 0.7% calcium chloride aqueous solution to begin to become turbid. The addition of 0.7% calcium chloride per ml l equates to 2.53mg of chelated Ca. The combined chelating agent (c) exhibits a synergistic effect in those compositions in which calcium chelation exceeds the value of either composition alone.

The calcium-chelating ability of composition (a) and composition (b) was measured separately. Subsequently, the chelating ability of the mixed composition (c) prepared by combining the composition (a) and the composition (b) in a given ratio was measured using turbidity titration under the same conditions.

As indicated above, the combination of composition (a) and composition (b) is considered to be synergistic if the chelating capacity is greater than that of either composition (a) or composition (b) alone. In addition, an unrefined glucarate/aluminate composition refers to a composition comprising glucarate, gluconate, 5-ketogluconate, tartrate, tartronate, glycolate, and aluminate, while a refined glucarate/aluminate component refers to a composition comprising only glucarate and aluminate. The results of this experiment are given in tables 1-13 below. In all cases, the amount of anionic chelating agent used was calculated as the sodium salt.

TABLE 1

TABLE 2

TABLE 3

TABLE 4

TABLE 5

TABLE 6

TABLE 7

TABLE 8

TABLE 9

Watch 10

TABLE 11

TABLE 12

Watch 13

As demonstrated from the data in the tables above, the purified glucarate/aluminate and citrate, the unpurified glucarate/aluminate and citrate, and the unpurified glucarate/borax and citrate compositions exhibit an unexpected synergistic increase in calcium chelating capacity over that provided by either chelating agent alone. The chelating abilities of the unpurified glucarates and citrates and aluminates and citrates provided in tables 10 and 12 are predictable, demonstrating that the synergistic performance does not depend on these combinations alone. Rather, the synergistic performance depends on the action exerted by all three types of chelating agents together (constancy), namely hydroxymonocarboxylates and/or hydroxydicarboxylates, oxyacid anions and citrates. It is additionally noted in tables 7 and 8 that this phenomenon is specific to citrate and does not extend to other common chelating agents such as EDTA and NTA.

Claims (36)

1. A calcium sequestering composition comprising a combination of:

(a) at least one salt of a hydroxycarboxylic acid selected from the group consisting of a salt of a hydroxymonocarboxylic acid, a salt of a hydroxydicarboxylic acid, and mixtures thereof;

(b) at least one salt of an oxoacid anion; and

(c) at least one citrate salt.

2. The calcium sequestering composition of claim 1, wherein the hydroxymonocarboxylic acid salt comprises a salt of glycolic acid, a salt of gluconic acid, a salt of 5-keto-gluconic acid, or a mixture thereof.

3. The calcium sequestering composition of claim 2, wherein the salt of glycolic acid comprises: sodium glycolate, potassium glycolate, lithium glycolate, zinc glycolate, ammonium glycolate or a mixture thereof.

4. The calcium sequestering composition of claim 2, wherein the at least one salt of a hydroxymonocarboxylic acid comprises at least one salt of gluconic acid.

5. The calcium sequestering composition of claim 4, wherein the at least one salt of gluconic acid comprises: sodium gluconate, potassium gluconate, lithium gluconate, zinc gluconate, ammonium gluconate or mixture thereof.

6. The calcium sequestering composition of claim 2, wherein the at least one salt of a hydroxymonocarboxylic acid comprises at least one salt of 5-keto-gluconic acid.

7. The calcium sequestering composition of claim 6, wherein the at least one salt of 5-keto-gluconic acid comprises: 5-ketone-sodium gluconate, 5-ketone-potassium gluconate, 5-ketone-lithium gluconate, 5-ketone-zinc gluconate, and 5-ketone-ammonium gluconate or their mixture.

8. The calcium sequestering composition of claim 1, wherein the hydroxy dicarboxylate salt comprises at least one salt of glucaric acid, at least one salt of tartaric acid, at least one salt of tartronic acid, at least one salt of xylaric acid, at least one salt of galactaric acid, or a mixture thereof.

9. The calcium sequestering composition of claim 8, wherein the at least one salt of glucaric acid comprises: disodium glucarate, sodium potassium glucarate, dipotassium glucarate, zinc glucarate, diammonium glucarate, dilithium glucarate, lithium sodium glucarate, lithium potassium glucarate or a mixture of the above.

10. The calcium sequestering composition of claim 8, wherein the at least one salt of tartaric acid comprises disodium tartrate, sodium potassium tartrate, dipotassium tartrate, dilithium tartrate, lithium sodium tartrate, lithium potassium tartrate, zinc tartrate, diammonium tartrate, or a mixture thereof.

11. The calcium sequestering composition of claim 8, wherein the at least one salt of tartronic acid comprises: disodium tartronate, sodium potassium tartronate, dipotassium tartronate, dilithium tartronate, lithium sodium tartronate, lithium potassium tartronate, zinc tartronate, diammonium tartronate, or mixtures thereof.

12. The calcium sequestering composition of claim 1, wherein the at least one salt of a hydroxycarboxylic acid comprises a mixture of at least one glucarate salt, at least one gluconate salt, at least one 5-keto-gluconate salt, at least one tartrate salt, at least one tartronate salt, and at least one glycolate salt.

13. The calcium sequestering composition of claim 1, wherein the composition comprises about 30% to about 75% by weight of the at least one glucarate salt, about 0% to about 20% by weight of the at least one gluconate salt, about 0% to about 10% by weight of the at least one 5-keto-gluconate salt, about 0% to about 10% by weight of the at least one tartrate salt, about 0% to 10% by weight of the at least one tartronate salt, and about 0% to 10% by weight of the at least one glycolate salt.

14. The calcium sequestering composition of claim 1, wherein the composition comprises about 40% to about 60% by weight of the at least one glucarate salt, about 5% to about 15% by weight of the at least one gluconate salt, about 3% to about 9% by weight of the at least one 5-keto-gluconate salt, about 5% to about 10% by weight of the at least one tartrate salt, about 5% to 10% by weight of the at least one tartronate salt, and about 1% to 5% by weight of the at least one glycolate salt.

15. The calcium sequestering composition of claim 1, wherein the composition comprises about 45% to about 55% by weight of the at least one glucarate salt, about 10% to about 15% by weight of the at least one gluconate salt, about 4% to about 6% by weight of the at least one 5-keto-gluconate salt, about 5% to about 7% by weight of the at least one tartrate salt, about 5% to 7% by weight of the at least one tartronate salt, and about 3% to 5% by weight of the at least one glycolate salt.

16. The calcium sequestering composition of claim 1, wherein the mixture comprises about 50% by weight of the at least one glucarate salt, about 15% by weight of the at least one gluconate salt, about 4% by weight of the at least one 5-keto-gluconate salt, about 6% by weight of the at least one tartrate salt, about 6% by weight of the at least one tartronate salt, and about 5% by weight of the at least one glycolate salt.

17. The calcium sequestering composition of claim 1, wherein the salt of an oxoacid anion comprises a borate, an aluminate, a stannate, a germanate, a molybdate, an antimonate, or a mixture thereof.

18. The calcium sequestering composition of claim 1, wherein the at least one salt of an oxoacid anion comprises: sodium borate, potassium borate, disodium octaborate, sodium metaborate, sodium molybdate, potassium molybdate, sodium aluminate, potassium aluminate, sodium aluminum stannate chloride, potassium stannate, sodium germanate, potassium germanate, sodium antimonite, potassium antimonite or a mixture thereof.

19. The calcium sequestering composition of claim 1, wherein the at least one citrate salt comprises: sodium citrate, potassium citrate, calcium citrate, magnesium citrate or their mixture.

20. The calcium sequestering composition of claim 1, wherein the calcium sequestering composition comprises from about 25% to about 75% by weight of the at least one salt of a hydroxycarboxylic acid, from about 1% to about 50% by weight of the at least one oxoacid anion salt, and from about 1% to about 10% by weight of the at least one citric acid salt.

21. The calcium sequestering composition of claim 1, wherein the composition comprises from about 40% to about 60% by weight of the at least one salt of hydroxycarboxylic acid, from about 10% to about 35% by weight of the at least one oxoacid anion salt, and from about 10% to about 35% by weight of the at least one citric acid salt.

22. The calcium sequestering composition of claim 1, wherein the composition comprises about 50% by weight of the at least one salt of hydroxycarboxylic acid and about 20% by weight of the at least one oxoacid anion salt, and about 30% by weight of the at least one citric acid salt.

23. A method of sequestering calcium ions from a medium comprising applying a composition comprising a combination of at least one salt of a hydroxycarboxylic acid selected from the group consisting of: hydroxy monocarboxylates, hydroxy dicarboxylates and mixtures thereof.

24. The method of claim 23, wherein the at least one salt of a hydroxycarboxylic acid comprises a mixture of at least one glucarate salt, at least one gluconate salt, at least one 5-keto-gluconate salt, at least one tartrate salt, at least one tartronate salt, and at least one glycolate salt.

25. The method of claim 24, wherein the at least one salt of a hydroxycarboxylic acid comprises about 30% to about 75% by weight of the at least one glucarate salt, about 0% to about 20% by weight of the at least one gluconate salt, about 0% to about 10% by weight of the at least one 5-keto-gluconate salt, about 0% to about 10% by weight of the at least one tartrate salt, about 0% to 10% by weight of the at least one tartronate salt, and about 0% to 10% by weight of the at least one glycolate salt.

26. The method of claim 24, wherein the at least one salt of a hydroxycarboxylic acid comprises about 40% to about 60% by weight of the at least one glucarate salt, about 5% to about 15% by weight of the at least one gluconate salt, about 3% to about 9% by weight of the at least one 5-keto-gluconate salt, about 5% to about 10% by weight of the at least one tartrate salt, about 5% to 10% by weight of the at least one tartronate salt, and about 1% to 5% by weight of the at least one glycolate salt.

27. The method of claim 24, wherein the at least one salt of a hydroxycarboxylic acid comprises about 45% to about 55% by weight of the at least one glucarate salt, about 10% to about 15% by weight of the at least one gluconate salt, about 7% to about 9% by weight of the at least one 5-keto-gluconate salt, about 4% to about 6% by weight of the at least one tartrate salt, about 5% to 7% by weight of the at least one tartronate salt, and about 3% to 5% by weight of the at least one glycolate salt.

28. The method of claim 24, wherein the at least one salt of a hydroxycarboxylic acid comprises about 50% by weight of the at least one glucarate salt, about 15% by weight of the at least one gluconate salt, about 4% by weight of the at least one 5-keto-gluconate salt, about 6% by weight of the at least one tartrate salt, about 6% by weight of the at least one tartronate salt, and about 5% by weight of the at least one glycolate salt.

29. The method of claim 23, wherein the salt of an oxoacid anion comprises: borate, aluminate, stannate, germanate, molybdate, antimonate or mixtures thereof.

30. The method of claim 23, wherein the at least one salt of an oxoacid anion comprises: sodium borate, potassium borate, disodium octaborate, sodium metaborate, sodium molybdate, potassium molybdate, sodium aluminate, potassium aluminate, sodium aluminum stannate chloride, potassium stannate, sodium germanate, potassium germanate, sodium antimonite, potassium antimonite or a mixture thereof.

31. The method of claim 23, wherein the at least one citrate salt comprises: sodium citrate, potassium citrate, calcium citrate, magnesium citrate or their mixture.

32. The method of claim 23, wherein the calcium sequestering composition comprises from about 25% to about 75% by weight of the at least one salt of hydroxycarboxylic acid, from about 1% to about 50% by weight of the at least one oxoacid anion salt, and from about 1% to about 10% by weight of the at least one citric acid salt.

33. The method of claim 23, wherein the composition comprises from about 40% to about 60% by weight of the at least one salt of hydroxycarboxylic acid, from about 10% to about 35% by weight of the at least one oxoacid anion salt, and from about 10% to about 35% by weight of the at least one citric acid salt.

34. The method of claim 23, wherein the composition comprises about 50% by weight of the at least one salt of hydroxycarboxylic acid and about 20% by weight of the at least one oxoacid anion salt, and about 30% by weight of the at least one citric acid salt.

35. A detergent composition comprising:

(a) at least one salt of a hydroxycarboxylic acid selected from the group consisting of a salt of a hydroxymonocarboxylic acid, a salt of a hydroxydicarboxylic acid, and mixtures thereof;

(b) at least one salt of an oxoacid anion; and

(c) at least one citrate salt.

36. The detergent composition of claim 35, further comprising one or more additional functional materials each independently selected from rinse aids, bleaches, disinfectants/antimicrobials, activators, detergent builders or fillers, pH buffers, fabric relaxants, fabric softeners, soil release agents, defoamers, anti-redeposition agents, stabilizers, dispersants, optical brighteners, antistatic agents, anti-wrinkle agents, odor capture agents, fiber protection agents, color protection agents, dyes/odorants, UV protectants, anti-pilling agents, water repellents, hardeners/solubility modifiers, glass and metal corrosion inhibitors, enzymes, soil release agents, oxidizing agents, solvents and insect repellents.