Title:
Detergent formulations containing alkaline peroxide salts and organic acids
Kind Code:
A1


Abstract:
The invention provides particulate detergent compositions containing alkaline peroxide salts and organic peracid precursors, methods of treating stains with these compositions and methods of making the compositions. The compositions have long term storage stability imparted by a coating to the alkaline peroxide salt. The methods of formulating the compositions to include this coating are relatively easy and inexpensive.



Inventors:
Manske, Scott D. (Pleasanton, CA, US)
Holzhauer, Frederick W. (Edgewater, CO, US)
Baker, Laura Windsor (Charlotte, NC, US)
Application Number:
10/856743
Publication Date:
03/24/2005
Filing Date:
05/27/2004
Assignee:
MANSKE SCOTT D.
HOLZHAUER FREDERICK W.
BAKER LAURA WINDSOR
Primary Class:
Other Classes:
510/446
International Classes:
C11D3/20; C11D3/39; C11D17/00; D06L1/00; (IPC1-7): D06L1/00
View Patent Images:
Related US Applications:
20090241266WASHER AND DRYER SHEET WITH VISUAL INDICATOROctober, 2009Thielke et al.
20010001783RETINOL STABILIZED CLEANSING COMPOSITIONSMay, 2001Nystrand et al.
20080234161Solid Detergent BarSeptember, 2008Iyer et al.
20040152618Particles containing fabric conditionerAugust, 2004Mistry et al.
20090008806REACTION VESSEL FOR AN OZONE CLEANING SYSTEMJanuary, 2009Lynn
20040147423Dual-compartment laundry composition containing peroxyacidsJuly, 2004Scialla et al.
20020183230Enzymatic liquid cleaning composition exhibiting enhanced alpha-amylase enzyme stabilityDecember, 2002Song et al.
20030176307Enzyme containing tabletsSeptember, 2003Housmekerides et al.
20060293210Desalting of hydrocarbonsDecember, 2006Ortega et al.
20090301996FORMULATIONS FOR REMOVING COOPER-CONTAINING POST-ETCH RESIDUE FROM MICROELECTRONIC DEVICESDecember, 2009Visintin et al.
20100022428ANTI-GREY DETERGENTJanuary, 2010Warkotsch et al.



Primary Examiner:
HARDEE, JOHN R
Attorney, Agent or Firm:
Sheridan Ross PC (Denver, CO, US)
Claims:
1. A particulate solid detergent composition having increased storage stability, comprising: a. an alkaline peroxide salt coated with a surfactant; and b. a peracid precursor selected from the group consisting of carboxylic acids and salts thereof.

2. The detergent composition of claim 1, wherein the alkaline peroxide salt is selected from the group consisting of sodium percarbonate and sodium perborate.

3. The detergent composition of claim 1, wherein the alkaline peroxide salt is present in an amount from about 20% to about 80% by weight.

4. The detergent composition of claim 1, wherein the peracid precursor is selected from the group consisting of dicarboxylic and tricarboxylic acids.

5. The detergent composition of claim 1, wherein the peracid precursor is selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, tannic acid, tartaric acid and citric acid and combinations thereof.

6. The detergent composition, as claimed in claim 5, wherein the peracid precursor is tartaric acid.

7. The detergent composition of claim 1, wherein the peracid precursor is present in an amount from about 0.1% to about 10% by weight.

8. The detergent composition of claim 1, wherein the peracid precursor is present in an amount from about 0.7% to about 2% by weight.

9. The detergent composition of claim 1, wherein the surfactant comprises at least one non-ionic surfactant.

10. The detergent composition of claim 9, wherein the non-ionic surfactant comprises an 11 to 16 carbon alcohol ethoxylate.

11. The detergent composition of claim 10, wherein the alcohol ethoxylate is selected from the group consisting of GENOPOL LA060™, GENOPOL UD-030™ and combinations thereof.

12. The detergent composition of claim 1, wherein the composition further comprises a surfactant substrate.

13. The detergent composition of claim 12, wherein the surfactant substrate is selected from the group consisting of sodium carbonate, sodium sulfate and combinations thereof.

14. The detergent composition of claim 1, wherein the composition further comprises a metals protectant.

15. The detergent composition, as claimed in claim 12, wherein the metals protectant is sodium metasilicate.

16. The detergent composition of claim 1, wherein the composition further comprises a dispersive agent.

17. The detergent composition, as claimed in claim 16, wherein the dispersive agent is selected from the group consisting of acrylic derived polymers and rosin soaps.

18. The detergent composition of claim 16, wherein the dispersive agent is a maleic/acrylic acid copolymer.

19. The detergent composition of claim 1, wherein the composition further comprises a water soluble solvent.

20. The detergent composition, as claimed in claim 19, wherein the water soluble solvent is selected from the group consisting of dipropylene glycol methyl ether, ethylene glycol butyl ether and combinations thereof.

21. A process for the treatment of a stain on a fabric, comprising contacting the stained fabric with a detergent composition comprising an alkaline peroxide salt coated with a surfactant and a peracid precursor selected from the group consisting of carboxylic acids and salts thereof.

22. The process of claim 21, wherein the alkaline peroxide salt is selected from the group consisting of sodium percarbonate and sodium perborate.

23. The process of claim 21, wherein the alkaline peroxide salt is selected from the group consisting of sodium percarbonate and sodium perborate.

24. The process of claim 21, wherein the alkaline peroxide salt is present in an amount from about 20% to about 80% by weight.

25. The process of claim 21, wherein the peracid precursor is selected from the group consisting of dicarboxylic and tricarboxylic acids.

26. The process of claim 21, wherein the peracid precursor is selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, tannic acid, tartaric acid and citric acid and combinations thereof.

27. The process of claim 26, wherein the peracid precursor is tartaric acid.

28. The process of claim 21, wherein the peracid precursor is present in an amount from about 0.1% to about 10% by weight.

29. The process of claim 21, wherein the peracid precursor is present in an amount from about 0.7% to about 2% by weight.

30. The process of claim 21, wherein the surfactant comprises at least one non-ionic surfactant.

31. The process of claim 30, wherein the non-ionic surfactant comprises an 11 to 16 carbon alcohol ethoxylate.

32. The process of claim 31, wherein the alcohol ethoxylate is selected from the group consisting of GENOPOL LA060™, GENOPOL UD-030™ and combinations thereof.

33. The process of claim 21, wherein the composition further comprises a surfactant substrate.

34. The process of claim 33, wherein the surfactant substrate is selected from the group consisting of sodium carbonate, sodium sulfate and a combination thereof.

35. The process of claim 21, wherein the composition further comprises a metals protectant.

36. The process of claim 35, wherein the metals protectant is sodium metasilicate.

37. The process of claim 21, wherein the composition further comprises a dispersive agent.

38. The process of claim 37, wherein the dispersive agent is selected from the group consisting of acrylic derived polymers and rosin soaps.

39. The process of claim 38, wherein the dispersive agent is a maleic/acrylic acid copolymer.

40. The process of claim 21, wherein the composition further comprises a water soluble solvent.

41. The process of claim 40, wherein the water soluble solvent is selected from the group consisting of dipropylene glycol methyl ether, ethylene glycol butyl ether and a combination thereof.

42. A detergent composition, comprising: a. about 50% to about 60% by weight of an alkaline peroxide salt, wherein said alkaline peroxide salt is coated with a surfactant; b. about 0.7% to about 2% by weight of a peracid precursor selected from the group consisting of carboxylic acids and salts thereof.

43. The detergent composition, as claimed in claim 42, further comprising: a. about 30% to about 40% by weight of sodium carbonate; b. about 0.7% to about 2% by weight of sodium metasilicate; c. about 0.2% to about 5% by weight of maleic/acrylic acid copolymer; d. about 0.3% to about 0.5% by weight of dipropylene glycol methyl ether; e. about 0.2% to about 5% by weight of linear 10-14 carbon alcohol ethoxylate; and f. about 0.2% to about 5% by weight of an 11 carbon alcohol ethoxylate.

44. A method of making a particulate solid detergent comprising: a. contacting an alkaline peroxide salt with a solution comprising a surfactant to form a coated alkaline peroxide salt; and, b. adding a peracid precursor to the coated alkaline peroxide salt to form a particulate solid composition having enhanced storage stability.

45. The method of claim 44, wherein the surfactant is a non-ionic surfactant.

46. The method of claim 45, wherein the non-ionic surfactant comprises an 11 to 16 carbon alcohol ethoxylate.

47. The process of claim 46, wherein the alcohol ethoxylate is selected from the group consisting of GENOPOL LA060™, GENOPOL UD-030™ and combinations thereof.

48. The method of claim 44, wherein the solvent is water soluble.

49. The method of claim 44, wherein the solvent is dipropylene glycol methyl ether.

50. The method of claim 44, wherein the contacting step comprises: a. contacting a surfactant substrate with the solution; and, b. mixing an alkaline peroxide salt with the surfactant substrate, wherein the alkaline peroxide salt absorbs the solution from a surface of the surfactant substrate.

51. The method of claim 44, wherein the alkaline peroxide salt is selected from the group consisting of sodium percarbonate and sodium perborate.

52. The method of claim 44, wherein the alkaline peroxide salt is present in the particulate solid detergent in an amount from about 20% to about 80% by weight.

53. The method of claim 44, wherein the peracid precursor is selected from the group consisting of dicarboxylic and tricarboxylic acids.

54. The method of claim 44, wherein the peracid precursor is selected from the group consisting of oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, tannic acid, tartaric acid and citric acid and combinations thereof.

55. The method of claim 54, wherein the peracid precursor is tartaric acid.

56. The method of claim 44, comprising the additional step of adding an ingredient selected from the group consisting of nonionic surfactants, surfactant substrates, metal protectants, dispersants, enzymatic stain removers, fluorescent whiteners, optical brighteners, buffers, colorants, fragrances, detergency builders, peroxide stabilizers and bulking agents to the coated alkaline peroxide salt following the addition of the peracid precursor.

57. A dry particulate detergent composition comprising an alkaline peroxide salt, a solvent and a peracid precursor selected from the group consisting of carboxylic acids and salts thereof made by the method comprising: a. combining a surfactant with a solvent to form a solution; b. contacting an alkaline peroxide salt with the solution to form an alkaline peroxide salt; c. adding a peracid precursor to the coated alkaline peroxide salt to form a particulate solid composition having enhanced storage stability.

Description:

CROSS REFERENCE TO RELATED APPLICATIONS

This application claims priority to U.S. Provisional Patent Application Ser. No. 60/475,020, filed May 30, 2003, which is incorporated herein in its entirety by this reference.

FIELD OF THE INVENTION

The invention resides in the field of cleaning compositions having a combination of alkaline peroxide salts and peracid precursor activators in a formulation having long term storage stability.

BACKGROUND OF THE INVENTION

Chlorine-containing fabric bleaching agents have superior cleaning properties but are limited to the cleaning of compatible fabrics and cannot be used to clean colored or figured fabrics. Additionally, these agents have a peculiar smell that may be imparted to certain fabrics when used in high concentrations. For these reasons, there has been great interest in the development of oxygen-containing bleaching agents that do not suffer from these limitations.

Among the oxygen-containing bleaching agents, sodium percarbonate and sodium perborate are particularly useful by virtue of their bleaching capacity and stability. Peroxygen bleaches are safe to fabric colors and are relatively nonyellowing to white fabric. They are nondestructive to the physical strength of the fabric and impart a good handle and absorbency to fabric. Such peroxygen bleaches have been used primarily for stain and soil removal in two distinct laundry settings. The first setting employs high wash temperatures, particularly over 185° F. often found in commercial laundries and in some European domestic laundries. At these high temperatures, a peroxygen material such as hydrogen peroxide or sodium perborate or percarbonate can be added to the wash mixture and will give effective bleaching. Lower temperatures are typically found in United States domestic washing machines. For these lower temperatures, the combination of hydrogen peroxide with activators have been used successfully. A range of materials have been proposed as activators for peroxygen bleaches to enhance bleaching at low to moderate temperatures.

The selection of peroxygen bleach-activator combinations is a complex balancing of two contradictory characteristics. The combination must be storage-stable and not undergo a significant loss of its activity (e.g., no more than 10-20% over a 90 day period at 59° F.-86° F.). On the other hand, the combination must be reactive enough that it will react within 1-2 minutes of being added to a cold water (50° F.-86° F.) laundry solution so as to be effective through most of the 10-12 minute wash period of a residential automatic washer cycle. Thus, a peroxygen compound-activator combination must exhibit a reaction rate in the washing machine that is 10,000 to 100,000 times as fast as the decomposition rate which is tolerable during storage.

U.S. Pat. No. 3,833,506 to Fries et al. teaches a stabilized bleaching assistant suitable for addition to washing and bleaching compositions containing an activator for active oxygen and a mixture of fatty acids and polyethylene glycol. The activators disclosed are carboxylic acid derivatives which react with the percompounds to form peracids and therefore increase the bleaching action of the mixtures or make it possible to bleach at low washing temperatures. The bleaching assistant formulation is stabilized by spraying a combination of the activator, a fatty acid and polyethylene glycol into a solidification zone to form particles having a diameter less than 1 mm. However, the stability testing conducted with this product showed the active bleaching ingredient perborate fell below 90% efficacy after storage for 21 to 28 days and dropped below 40% efficacy after six weeks. Thus, this formulation method is technically complex and expensive and the resulting product still shows insufficient stability for storage, shipping and customer use.

U.S. Pat. No. 5,702,635 to Trani and Ricci discloses a granular laundry detergent containing percarbonate coated or agglomerated with hydrophobic acylated esters of citric acid having increased stability. The acylated esters of citric acid coat the detergent particles to stabilize the percarbonate during storage, while acting as a bleach activator during aqueous washing conditions. The composition is formed by spraying the acylated esters of citric acid onto the granular percarbonate particles or onto the completed composition including percarbonate and other additives after all other ingredients have been combined. However, these acylated esters of citric acid are strongly hydrophobic which limits the formulation options and negatively impacts dissolution rates of the coated product into water.

U.S. Pat. No. 5,716,923 to MacBeath teaches a laundry detergent having a percarbonate bleach coated with a mixed salt containing an alkali metal carbonate and an alkali metal sulfate salt. The detergent also contains a peroxyacid bleach precursor, an acidification agent and a means for delaying the release of the acidification agent. The coated percarbonate is storage stable while the delayed acidification lowers the pH of the laundry below pH 9.5 in the final wash solution. The coating that effects the delayed release of the acidification agent is a dual coating of an inner wax and an outer silica produced in a functional multi-layered coating process that makes the coating and formulation of these dry detergents complex and expensive.

Thus, there exists a need for fabric detergent formulations that combine the cleaning activity of peroxygen bleaches and peroxygen bleach activators in a storage stable composition that is relatively easy and inexpensive to formulate.

SUMMARY OF THE INVENTION

The present invention provides particulate detergent compositions that combine peroxygen bleaches having a surfactant coating and peroxygen bleach activators as well as methods of easily and inexpensively formulating these detergent compositions to have long term storage stability and methods of using these detergent compositions to treat fabric stains. The compositions contain an alkaline peroxide salt coated with a surfactant and a peracid precursor consisting of carboxylic acids and salts thereof. Preferably, the alkaline peroxide salt is sodium percarbonate or sodium perborate present in an amount of about 20% to about 80% of the composition by weight. Preferably, the peracid precursors are dicarboxylic or tricarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, tannic acid, tartaric acid or citric acid or combinations thereof present in an amount from about 0.1% to about 10% of the composition by weight. The preferred surfactant is at least one non-ionic surfactant, particularly an 11 to 16 carbon alcohol ethoxylate or mixtures of these alcohol ethoxylates.

The composition optionally contains other wash aids including surfactant substrates such as sodium carbonate and/or sodium sulfate, metals protectants such as sodium metasilicate, dispersive agents such as acrylic derived polymers and rosin soaps, water soluble solvents such as dipropylene glycol methyl ether and/or ethylene glycol butyl ether, enzymatic stain removers, fluorescent whiteners, optical brighteners, buffers, colorants, fragrances, detergency builders, peroxide stabilizers and bulking agents

The processes of formulating the solid detergent compositions of the present invention provide inexpensive methods of combining and coating the detergent components to form compositions having increased storage stability. These methods include combining a surfactant with a solvent to form a solution and coating an alkaline peroxide salt with the solution to form a coated alkaline peroxide salt. A peracid precursor is then added to the coated alkaline peroxide salt. Preferably, the composition contains a surfactant substrate which is first coated with the solution and then mixed with an alkaline peroxide salt such that the alkaline peroxide salt absorbs the solution from the surface of the surfactant substrate.

BRIEF DESCRIPTION OF THE DRAWINGS

FIGS. 1(a-c) show the results of the fabric cleaning test described in Example 1 comparing a one-hour, three-hour and a five-hour presoak with a detergent composition of the present invention.

FIGS. 2(a-c) show the results of the fabric testing described in Example 2 comparing detergent compositions of the present invention having a peracid precursor additive with similar compositions having no peracid precursor on various fabric stains.

FIG. 3 is a graphical representation of total Delta E for different stains on cotton and poly/cotton comparing treating with compositions of the present invention and commercially available detergents.

FIG. 4 is a graphical representation of total Delta E for different stains treated with detergent compositions of the present invention compared to compositions lacking a peracid precursor.

FIG. 5 is a graphical representation of total Delta E for different stains on cotton or cotton blend fabrics comparing formulations of the present invention having different peracid precursors with commercially available detergents.

FIG. 6 shows a graphical representation of total Delta E for different standard dye types on fabrics treated with detergent compositions of the present invention having different peracid precursors compared to commercially available detergents.

FIG. 7 is a graphical representation comparing the oxidation-reduction potential developed by detergent compositions of the present invention with similar compositions lacking peracid precursors with curve fitting done exponentially.

DETAILED DESCRIPTION OF THE INVENTION

The present invention provides detergent formulations containing alkaline peroxide salts and organic acid bleach activators that have long shelf life and high stability, and are particularly useful in cleaning fabrics. These formulations contain an alkaline peroxide salt and a peracid precursor coated with a surfactant.

The alkaline peroxide salts are oxygen-containing bleaching agents including sodium percarbonate and sodium perborate. Preferably, the peroxide salt is sodium percarbonate. As used herein, the term “alkaline peroxide salts” refers to hydrates and other cations of the alkaline peroxide salts. The alkaline peroxide salt can comprise a single chemical species or a combination of different chemical species. The peroxide salt is present in the formulation in a range of about 1% to about 99% of the formulation by weight. Preferably, the peroxide salt is present in a range of about 20% to about 80% by weight. More preferably, the peroxide salt is present in a range of about 40% to about 60% by weight. Even more preferably, the peroxide salt is present in a range of about 50% to about 60% by weight. Most preferably, the peroxide salt is present at about 56% by weight.

The peracid precursor activates the alkaline peroxide salts in solution to produce organic peroxides. The peracid precursor can comprise a single chemical species or a combination of different chemical species. The peracid precursor of the invention is selected from organic acids and their salts. For peracid precursors having different isomeric forms, all isomers may be functional in the compositions of the present invention. Preferred dicarboxylic acids include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, tannic acid and tartaric acid. A functional tricarboxylic acid is citric acid. More preferably, peracid precursors include tartaric acid, adipic acid and/or citric acid, with tartaric being most preferred. The peracid precursors are typically present in the formulation in a range of about 0.1% to about 10% of the formulation by weight. Preferably, the peracid precursor is present in a range of about 0.5% to about 5% by weight. More preferably, the peracid precursor is present in a range of about 0.7% to about 2% by weight. Most preferably, the peracid precursor is present at about 1% by weight.

While other peracid precursors are known in the art (such as tetraacetylethylenediamine (TAED) and nonanoyloxybenzene sulfonate (NOBS)), the peracid precursors of the present invention have significant advantages over known peracid precursors. In contrast to TAED and NOBS, many organic acid peracid precursors of the present invention occur widely in nature and are recognized as being benign to the environment. In addition, many organic acid peracid precursors are inexpensive and can be economically used at concentrations identified above, thereby providing a more cost effective system.

Formulations of the present invention can also include a water soluble solvent. While many water soluble solvents are known to those in the field, preferred water soluble solvents include dipropylene glycol methyl ether (1-(2-methoxyisopropoxy)-2-propanol) and ethylene glycol butyl ether (2-butoxyethanol). The water soluble solvent is typically present in the formulation in a range of about 0.1% to about 10% by weight. Preferably, the water soluble solvent is present in a range of about 0.2% to about 5% by weight. More preferably, the water soluble solvent is present in a range of about 0.3% to about 0.5% by weight. Most preferably, the water soluble solvent is present at about 0.4% by weight.

Formulations of the present invention can also include a surfactant or surfactants to aid in the solubilization of non-water soluble materials. For example, useful nonionic surfactants include linear 10 to 14 carbon alcohol ethoxylates or 11 carbon alcohol ethoxylates. The surfactant(s) may vary widely in concentration within the formulations of the present invention. Typically, the surfactants are present in the formulation in a range of about 0.1% to about 20% by weight. Preferably, the surfactants are present in a range of about 0.2% to about 5% by weight. More preferably, the surfactants are present in a range of about 0.6% to 3% by weight.

Previously, it has been difficult to incorporate alkaline peroxide salts in effective levels in dry particulate laundry detergents due to the instability of these bleaches in storage. Sodium percarbonate loses its available oxygen at a significant rate in the presence of ions or heavy metals such as iron, copper and manganese and most importantly in the presence of moisture; these effects being accelerated at temperatures in excess of about 85° F.

Moisture and ions are unavoidable components of conventional granular laundry treatment compositions. Also decomposition of alkaline peroxide salts due to moisture becomes more of an issue during storage as laundry treatment products are often stored in humid environments in which the product picks up moisture resulting in only marginally acceptable bleach stability for laundry detergents containing alkaline peroxide salts shipped to warm and humid regions.

Such temperature-accelerated percarbonate decomposition also occurs during the manufacture of the finished product. Under some conditions, as individual ingredients are mixed together the temperature of the mixture may increase, accelerating the decomposition of the alkaline peroxide salt. Furthermore, the temperature increase is greater if the mixing occurs in humid conditions.

Additionally when an alkaline peroxide salt is combined with a bleach activator, stability during storage and production becomes an even greater problem. Indeed, mixing of an alkaline peroxide salt with a bleach activator during formulation of a dry particulate detergent can cause a rapid decomposition during the manufacture or the storage if the detergent composition is subjected to humid environments.

It is therefore an unexpected and advantageous discovery that a dry particulate detergent containing an alkaline peroxide salt and a carboxylic acid peracid precursor can be formulated to have a relatively long stable shelf life by coating the an alkaline peroxide salt particles with a surfactant. Surfactants normally function as surface active agents by bridging the interface between hydrophilic and hydrophobic compounds. Thus, given the difficulty in using alkaline peroxide salts in particulate detergents due to their reactivity with water and especially due to their reactivity with the combination of water and peracid precursors, it is unexpected that combining the alkaline peroxide salt with a substance that can enhance contact with water would stabilize the formulation. However, it has been found that coating the alkaline peroxide salt with a surfactant leads to greatly enhanced stability and therefore increased shelf life of the particulate detergent compositions of the present invention. This allows for the production of a stable particulate bleaching composition comprising an alkaline peroxide salt source of hydrogen peroxide together with a peracid bleach activator.

Stability testing conducted with detergent compositions of the present invention that measures the available oxygen content of the detergents immediately following formulation and at times points during storage of the detergent formulations shows that the compositions can retain greater than about 90% of their available oxygen after 60 days of storage under 50% humidity at 96° F. Preferably, the detergent compositions of the present invention are stable enough to retain greater than about 60% of their available oxygen after 60 days of storage under these conditions. More preferably, the detergent compositions of the present invention are stable enough to retain greater than about 70% of their available oxygen after 60 days of storage under these conditions. More preferably, the detergent compositions of the present invention retain greater than about 80% of their available oxygen after 60 days of storage under these conditions. More preferably, the detergent compositions of the present invention retain greater than about 90% of their available oxygen after 60 days of storage under these conditions. Most preferably, the detergent compositions of the present invention retain greater than about 95% of their available oxygen after 60 days of storage under these conditions.

For the purposes of this disclosure, coating the alkaline peroxide salt component of the detergent refers to contacting the alkaline peroxide salt with a surfactant such that at least one surface of the alkaline peroxide salt is in contact with the surfactant in the final detergent composition following formulation. Preferably, the surfactant coats or agglomerates at least half of each alkaline peroxide salt particle. Most preferably, the surfactant coats or agglomerates the entire surface of each alkaline peroxide salt particle.

The coated particulate particles of the present invention may be obtained by different methods known in the art, such as for instance, spraying or agglomerating or coating methods. For example, the surfactant or a combination of surfactants may be used either as an agglomerating or a coating agent to agglomerate or coat the particles of alkaline peroxide salt. A preferred method of coating the alkaline peroxide salt particles is to mix the chosen surfactants with a solvent to form a surfactant solution which is then combined with the alkaline peroxide salt to agglomerate or coat each alkaline peroxide salt particle. After the coating or agglomerating, the surfactant takes on a non-flowable consistency that acts as a barrier to water. To prepare the coated or agglomerated alkaline peroxide salt particles in this way, the solvent must be chosen for the characteristics of combining with the surfactant to form a solution and undergoing a change in consistency during or after formulation of the coated particles.

After the alkaline peroxide salt is added and sufficiently mixed to obtain a coating, the surfactant solution takes on a “gummy” non-flowable consistency believed to enhance the protection of the alkaline peroxide salt particles. Without intending to be bound by any theory, it is believed that the solvent present in the surfactant solution partially evaporates and is partially absorbed by the surfactant substrate thereby causing the change in the consistency of the surfactant solution which forms the non-flowable protectant barrier on the surface of the alkaline peroxide salt particles.

The most preferred method of forming the detergent compositions of the present invention is to form a solution of one or more non-ionic surfactants with a water soluble solvent. This solution is then mixed with a surfactant substrate in a proportion that results in the surfactant substrate coated with the surfactant solution with a residual amount of the surfactant solution remaining. Immediately thereafter, the alkaline peroxide salt is added to the mixture and mixed until the alkaline peroxide salt particles become coated by absorption of any residual surfactant solution from the surface of the surfactant substrate onto the surfaces of the alkaline peroxide salt. This method of mixing these ingredients assures an easy and inexpensive method of obtaining a light coating of at least one surfactant on the alkaline peroxide salt sufficient to protect the alkaline peroxide salt from water while remaining thin enough to allow full activity of the alkaline peroxide salt when the detergent composition is added to residential laundry water. Any other desired ingredients can then be added to the mixture to form detergent formulations of the present invention.

The preferred surfactant substrate for use in compositions of the present invention is sodium carbonate (soda ash) and the most preferred coating solution comprises a mixture of non-ionic surfactants including a linear 12-16 carbon alcohol ethoxylate such as GENOPOL LA060™ and an 11 carbon alcohol ethoxylate such as GENOPOL UD-030™ mixed with the water soluble solvent dipropylene glycol methyl ether. This surfactant solution is mixed and used to coat the sodium carbonate. An alkaline peroxide salt is then added to the mixture and blended until a light coating of the surfactant solution has been absorbed onto the surface of the alkaline peroxide salt particles. During this mixing and thereafter, the consistency of the coating changes from a liquid to a non-flowable form. Any additional wash aids desired are then added and blended with the mixture.

This combination of an alkaline peroxide salt coated with a surfactant is additionally advantageous in that the surfactant has well known functions in aiding in the cleaning of fabrics when the surfactants are introduced into the laundry water. Thus, the surfactant acts to protect and stabilize the particulate detergents of the present invention comprising alkaline peroxide salts and peracid precursors during formulation and storage while acting to liberate the alkaline peroxide salt and peracid when introduced into the laundry water and then functions separately to the activated bleaching compounds to aid in cleaning and stain removal of the fabrics present. These dual functions enhance the cleaning power of the detergents of the present invention while easing manufacturing, shipment and handling conditions for the dry formulations.

Formulations of the present invention can also include a substrate for surfactants, which will also function as a bulking agent. For example, the surfactant substrate can be sodium carbonate (soda ash) or sodium sulfate. Sodium carbonate functions as a buffer and is more absorptive than sodium sulfate and therefore, is preferred. Typically, the surfactant substrate is present in a range of about 1% to about 60% by weight. Preferably, surfactant substrate is present in a range of about 10% to about 50% by weight. More preferably, surfactant substrate is present in a range of about 30% to about 40% by weight. Most preferably, surfactant substrate is present at about 37% by weight.

Formulations of the present invention can also include a metals protectant that can also function as a soils dispersing agent and/or a buffer for pH. For example, the metals protectant can be sodium metasilicate, a polymeric metals protectant or a cationic metals protectant. Sodium metasilicate is more preferred because of ease of formulation compared to a polymeric or cationic metals protectant. Sodium metasilicate is typically present in the formulation in a range of about 0.1% to about 10% of the formulation by weight. Preferably, the sodium metasilicate is present in a range of about 0.5% to about 5% by weight. More preferably, the sodium metasilicate is present in a range of about 0.7% to about 2% by weight. Most preferably, the sodium metasilicate is present at about 1% by weight.

Formulations of the present invention can also include a dispersive agent. While many dispersive agents are known to those in the field, preferred dispersive agents include acrylic derived polymers, such as acrylic acid copolymers, and rosin soaps. Preferred acrylic acid copolymers are maleic/acrylic acid copolymers. The dispersive agent is typically present in the formulation in a range of about 0.1% to about 10% by weight. Preferably, the dispersive agent is present in a range of about 0.2% to about 5% by weight. More preferably, the dispersive agent is present at about 0.25% by weight. A preferred formulation of the present invention is shown in Table 1.

TABLE 1
ComponentWt. %CAS #Name
Surfactant substrate37.17  497-19-8Sodium carbonate
Non-ionic2.95 68551-12-2GENOPOL LA060 ™;
surfactantlinear C12-C16 alcohol
ethoxylate (6 moles
EO); Clariant
Corporation
Non-ionic0.65127036-24-2GENOPOL UD-030 ™;
surfactantC11 alcohol ethoxylate
(3 moles EO); Clariant
Corporation
Water soluble0.40 34590-94-8Dipropylene glycol
solventmethyl ether (1-(2-
methoxyisopropoxy)-2-
propanol); Lyonell
Alkaline peroxide56.58 15630-89-4Sodium percarbonate;
saltSolvay-Interox
Dispersive agent0.25 68479-09-4acrylic acid copolymer
˜4500 mole wt.,
sodium neutralized;
Rohm and Haas
Peracid precursor1.00  133-37-9D,L-Tartaric Acid;
Shengyu Chemical
Metals1.00 6834-92-0Blue Meta; Sodium
protectant/dispersiveMetasilicate,
agentanhydrous 100.00; PQ
Corporation

The composition of the present invention can optionally include additional wash aids. Representative wash aids include enzymatic stain removers. Such materials include enzymes capable of hydrolyzing substrates, e.g., fabric stains. Under the International Union of Biochemistry, accepted nomenclature for these types of enzymes is hydrolases. Hydrolases include, but are not limited to, proteases, amylases (carbohydrases), lipases (esterases), cellulases, and mixtures thereof. Proteases, especially so-called alkaline proteases, are commonly employed as wash aids, since they attack protein substrates and digest them, e.g., troublesome stains such as blood and grass. In various formulations of the present invention, enzymatic stain removers can optionally be included if dilution of the composition is great enough to reduce the pH of the solution to a range that does not inactivate the enzyme.

Another class of wash aid that can benefit from the practice of the invention is the fluorescent whiteners or optical brighteners although, as a rule, these materials take effect more quickly than enzyme stain removers and thus are less prone to attack by rapid onset of active oxygen. Representative fluorescent whitening agents include the naphtholtriazol stilbene and distyryl biphenyl fluorescent whitening agents sold by the Ciba-Geigy Corporation under the names Tinopal™ RBS and Tinopal™ CBS-X respectively, and the stilbene materials also marketed by Ciba-Geigy under the name Tinopal™ 5BMX. The Tinopal™ CBS-X brightner is the most peroxide stable brightner and is therefore the preferred brightening agent additive in formulations of the present invention. Other useful whiteners are disclosed in U.S. Pat. No. 3,393,153 which is incorporated herein by this reference and further useful whiteners are disclosed in ASTM publication D-553A, List of Fluroescent Whitening Agents for the Soap and Detergent Industry.

The compositions of the present invention may, if desired, contain additional components such as buffers, colorants, fragrances, primary cleansing agents (surfactants), detergency builders and bulking agents. In addition, peroxide stabilizers, such as heavy metal chelating ligands, for example EDTA, can be added, if desired.

Representative surfactants include conventional nonionic, cationic, anionic, amphoteric surfactant materials as are described in the art. Examples of suitable surfactants for use in these formulations may be found in Kirk-Othmer, Encyclopedia of Chemical Technology, 3rd Edition, volume 22, pages 247-387 (1983) and McCutcheon's Detergents and Emulsifiers, North American Edition (1983). One generally preferred group of surfactants are the nonionic surfactants such as are described at pages 360-377 of Kirk-Othmer. Nonionic materials include alcohol ethoxylates, alkyl phenol ethoxylates, carboxylic acid esters, glycerol esters, polyoxyethylene esters, anhydrosorbitol esters, ethoxylated anhydrosorbitol esters, ethoxylates of natural fats, oils and waxes, glycol esters of fatty acids, carboxylic amides, diethanolamine condensates, monoalkanolamine condensates, polyoxyethylene fatty acid amides, polyalkylene oxide block copolymers, poly(oxyethylene-co-oxypropylene) nonionic surfactants and the like. A wide range of such materials are available commercially, including the Shell Chemical Neodols™, the Union Carbide Tergitols™, the ICI Tween's™ and Spans™ and the like.

Detergency builders which may optionally be added to the bleach compositions can be selected from the detergency builders commonly added to detergent formulations. Useful builders include any of the conventional inorganic and organic water-soluble builder salts. Useful inorganic builder salts include, for example, water-soluble salts of phosphates, pyrophosphates, orthophosphates, polyphosphates, silicates, carbonates, and the like. Organic builders include water-soluble phosphonates, polyphosphonates, polyhydroxysulfonates, polyacetates, carboxylates, polycarboxylates, succinates, and the like.

Specific examples of inorganic phosphate builders include sodium and potassium tripolyphosphates, pyrophosphates, and hexametaphosphates. The organic polyphosphonates specifically include, for example, the sodium and potassium salts of ethane-1-hydroxy-1,1-diphosphonic acid and the sodium and potassium salts of ethane-1,1,2-triphosphonic acid. Examples of these and other phosphorous builder compounds are disclosed in U.S. Pat. Nos. 3,213,030; 3,422,021; 3,422,137; and 3,400,176. Pentasodium tripolyphosphate and tetrasodium pyrophosphate are especially preferred water-soluble inorganic builders.

Specific examples of nonphosphorous inorganic builders include water-soluble inorganic carbonate, bicarbonate, and silicate salts. The alkali metals, for example, sodium and potassium, carbonates, bicarbonates, and silicates are particularly useful in the formulations of the present invention.

Water-soluble organic builders are also useful. For example, the alkali metal, ammonium and substituted ammonium polyacetates, carboxylates, polycarboxylates, and polyhydroxysulfonates are useful builders for the compositions and processes of the invention. Specific examples of polyacetate and polycarboxylate builders include sodium, potassium, lithium, ammonium, and substituted ammonium salts of ethylene diaminetetraacetic acid, nitrilotriacetic acid, benzene polycarboxylic (i.e., penta- and tetra-) acids, carboxymethoxysuccinic acid and citric acid.

Water-insoluble builders may also be used, particularly the complex sodium alumino silicates such as zeolites, e.g., zeolite 4 A, a type of zeolite molecular sieve wherein the univalent cation is sodium and the pore size is about 4 Å. The preparation of a zeolite of this type is described in U.S. Pat. No. 3,114,603. The zeolite may be amorphous or crystalline and have waters of hydration as is known in the art.

Fillers or bulking agents may also be included in the bleaching compositions of the invention. A common filler salt is an alkali metal sulfate, such as potassium or sodium sulfate, the latter being preferred. The most preferred filler for use in compositions of the present invention is sodium carbonate (soda ash).

Compositions of the present invention are useful on a broad spectrum of stain types, including spaghetti, mustard, salad dressing, dirty motor oil, blood, grass, makeup, wine, juices, condiments, fruit filling, and fruit preserves.

Cleaning compositions of the present invention can be formulated in a variety of cleaning products, particularly for fabrics, including laundry cleaners, carpet cleaners, upholstery cleaners, and car interior cleaners. Those skilled in the art can formulate the compositions disclosed herein into a variety of product types.

Additional objects, advantages, and novel features of this invention will become apparent to those skilled in the art upon examination of the following examples thereof, which are not intended to be limiting.

EXAMPLES

Example 1

This example demonstrates the improved efficacy of the detergent composition described in Table 1 (hereinafter denoted as the “Improved Formulation”) in the removal of various types of stains from cotton, poly/cotton and cotton knit fabrics during a one-, three- or five-hour pre-soak.

Six-inch square swatches of prewashed, cut cotton cloth, polyester/cotton cloth, and cotton knit cloth were obtained from Testfabrics, Inc. (West Pittston, Pa.) Five different stains were tested: spaghetti, mustard, salad dressing, dirty motor oil, and blood. For each time point, duplicate swatches were used.

Stains were applied in the following manner. For spaghetti, 0.25 mL of RAGU™ Original was applied to each fabric swatch. For mustard, KROGER™ Traditional Yellow was applied to each fabric swatch by placing a small quantity of the mustard to the back of a rubber pipette bulb, then rubbing the mustard onto the fabric swatch. To approximate salad dressing stains, 0.25 mL KRAFT FREE™ Catalina dressing was applied to each swatch. For the dirty motor oil stain, 2 drops of used motor oil was applied to each swatch. Finally, for blood stains, 0.25 mL of cow blood was applied to each swatch.

After application of the stains, the swatches were allowed to age overnight. To each five-gallon soaking bucket, two gallons of water at 115° F. (±2°) was added along with 29.6 cc of the Improved Formulation. After the solution was stirred and the solid dissolved, the fabric swatches were added. The buckets were soaked for one hour, three hours, or five hours depending on their designations. Each bucket was agitated by hand after fifteen minutes and again at thirty minutes. After the designated time, the buckets were drained, and each group of swatches was washed using three-quarters cup Ultra Concentrated PUREX™ Laundry detergent and a ballast load, using a KENMORE™ 80 series 3.2 Cu. ft. washing machine and dried in a KENMORE™ Elite dryer.

After drying, all of the swatches were rated by two different raters. The following ratings procedure was used. Swatches from the three hour soak time were compared with swatches from the one hour soak time, and swatches from the five hour soak time were compared with swatches from the one hour soak time. The following ratings system was used. 4=Significantly better; 3=Noticeably better; 2=Better; 1=Slightly better; 0=Equal to control (Star if stain is completely removed); −1=Slightly poorer; −2=Poorer; −3=Noticeably Poorer; and −4=Significantly poorer. Table 3 shows three-hour soak results on cotton, poly/cotton, and cotton knit compared to one-hour soak times, and Table 4 shows five-hour soak results on cotton, poly/cotton, and cotton knit compared to one-hour soak times. FIGS. 1(a)-(c) provide a graphical representation of the results in Tables 2 and 3.

The results indicated that the performance of the Improved Formulation is increased over a longer soaking time. A soaking time of three hours compared to one hour showed some improvement for every stain type on poly/cotton, and for every stain type except for blood on cotton and cotton knit. Further improvement in stain removal performance was seen at five hours presoak time. However, for most stains, the most dramatic improvement in stain removal occurred between the one and three hour soak time, as compared to the one and five hour soak time. These results illustrated that formulations of the present invention having a peracid precursor generally provide improved cleaning results compared to formulations without a peracid precursor for most of the stain types evaluated.

TABLE 2
Removal of stains by the Improved Formulation from various
types of fabric during a three-hour presoak treatment
compared with a one-hour presoak treatment.
SpaghettiDirty MotorSalad
sauceMustardBloodOilDressing
poly/cotton0.87510.751.751.5
Cotton0.3751.25−1.37511
Cotton knit10.75−0.8751.750.25

TABLE 3
Removal of stains by the Improved Formulation from various
types of fabric during a five-hour presoak treatment
compared with a one-hour presoak treatment.
SpaghettiDirty MotorSalad
sauceMustard BloodOilDressing
poly/cotton2.252.125222.5
Cotton22.875−1.751.252.25
Cotton knit1.8751.50.6252.51.25

Example 2

This example compares the stain removal efficacy of two detergent formulations of the present invention containing different peracid precursors, with a formulation that does not contain peracid precursors that is described in Table 4 (hereinafter the “Comparison Formulation”).

TABLE 4
Components of the Comparison Formulation
ComponentWt. %CAS #Name
Surfactant38.17  497-19-8Sodium carbonate
substrate
Non-ionic2.95 68551-12-2GENOPOL LA060 ™; linear
surfactantC12-C16 alcohol ethoxylate (6
moles EO); Clariant Corporation
Non-ionic0.65127036-24-2GENOPOL UD-030 ™; C-11
surfactantalcohol ethoxylate (3 moles EO);
Clariant Corporation
Water0.40 34590-94-8DPM; Dipropylene glycol methyl
solubleether (1-(2-methoxyisopropoxy)-
solvent2-propanol); Lyonell
Alkaline56.58 15630-89-4Sodium percarbonate; Solvay-
peroxide saltInterox
Dispersive0.25 68479-09-4acrylic acid copolymer ˜4500
agentmole wt., sodium neutralized;
Rohm and Haas
Metals1.00 6834-92-0Blue Meta; Sodium Metasilicate,
protectant/anhydrous 100.00; PQ
dispersiveCorporation
agent

Six-inch square swatches of prewashed, cut cotton cloth, polyester/cotton cloth, and cotton knit cloth were obtained from Testfabrics, Inc. Four different stains were tested: spaghetti, mustard, dirty motor oil, and blood. Each stain was applied to six swatches of each fabric as described in Example 1. Two of the same-stain swatches were treated with the Comparison Formulation to which tartaric acid (Sigma Corp., St. Louis, Mo.) was added in a final weight percent equivalent to 1 wt. % tartrate, and two of the same-stain swatches were treated with the Improved Formulation to which potassium sodium tartrate (Sigma Corp., St. Louis, Mo.) was added in a final weight percent equivalent to 1 wt. % tartrate. The peracid precursors were added using standard industry procedures.

After application of the stains, the swatches were allowed to rest overnight. To each five-gallon soaking bucket, two gallons of water at 115° F. (±2°) was added along with 29.6 cc of the appropriate detergent additive. After the solution was stirred and the solid dissolved, the fabric swatches were added. The buckets were soaked for one hour, and each bucket was agitated by hand after fifteen minutes and again at thirty minutes. After the designated time, the buckets were drained, and each group of swatches were washed and dried as described in Example 1.

The detergent formulations containing either tartaric acid or potassium sodium tartrate were compared against the Comparison Formulation and rated as described in Example 1. Table 5 provides the results of the comparison with the detergent formulation containing tartaric acid on various stain types, and Table 6 provides the results of the comparison with the formulation containing potassium sodium tartrate on the same stain types. FIGS. 2(a) through (c) provide a graphical presentation of the results shown in Tables 5 and 6. These results demonstrate the improved performance of the detergent formulations having a peracid precursor additive compared with the Comparison Formulation for most stain types on all fabrics tested. Additionally, these results demonstrate that no significant differences are seen between using tartaric acid and using potassium sodium tartrate as a source of the tartrate peracid precursor in solution.

TABLE 5
Removal of stain from various types of fabric by the Comparison
Formulation with tartaric acid additive.
Spaghetti sauceMustardBloodDirty Motor Oil
Poly/cotton1.5−0.2502
Cotton0.750.7521
cotton knit1−0.1251.251

TABLE 6
Removal of stain from various types of fabric by the Comparison
Formulation with potassium sodium tartrate additive.
Spaghetti sauceMustardBloodDirty Motor Oil
Poly/cotton1.750.87502
Cotton0.75121
cotton knit1−0.3750.751.25

Example 3

This example compares the stain removal performance of the Improved Formulation, the Comparison Formulation and several commercially available laundry pretreatments.

Six inch square swatches of prewashed, cut cotton cloth and polyester/cotton cloth were obtained from Testfabrics, Inc. Nine different stains were tested: coffee, grape, spaghetti, blood, dressing, grass, makeup, mustard, and pie filling. Each stain was applied to duplicate swatches of each fabric for each pretreatment type. To apply the stains, the following staining procedures were used. Starting materials for each stain were those generally used in the laundry additive arts. The starting materials for grass and pie filling were homogenized. All stains were applied in an amount sufficient to create a saturated, 1-inch circle of stain on each fabric. Stained fabric swatches were allowed to age overnight, after which the fabric swatches were treated with the indicated treatments. Treatment conditions were as follows. For the Improved Formulation, the Comparison Formulation and SHOUT™, 8 grams of detergent was dissolved per 1 liter of water. CLOROX™ was used at 10 g/L water. The water was applied at a temperature of 104° F., and 150 ppm hardness. Soaking time was sixty minutes. After the designated time, the buckets were drained, and each group of swatches was washed and dried as described in Example 1.

After drying, the swatches were evaluated for stain removal. The color difference was described as a Delta E value. Spectrophometric values were obtained using an industry standard colorimeter (Minolta Corp, Ramsey, N.J.), and Delta E was computed using a method which measures L* (lightness), a*, (green-magenta axis), and b*, (yellow-blue axis), where Delta E describes the vector difference between the points in this space. The smallest color difference has the smallest Delta E value. Delta E values reported are relative to unstained cloth.

The results are shown in Tables 7-8 and FIG. 3. Tables 7 and 8 show the performance of each treatment type on each stain per fabric type, reported as Delta E units. The “Total” column is the sum of the Delta E measurement across all stain types, indicating the overall stain removal performance of each treatment type. FIG. 3 is a graphical representation showing the sum of total Delta E for each stain for cotton plus the total Delta E for each stain obtained for both poly/cotton and cotton. These results demonstrate that the Improved Formulation has the best overall stain-removal performance relative to the Comparison Formulation, SHOUT™ and CLOROX™.

TABLE 7
Comparison of the removal of various types of stains on
cotton cloth by several fabric pretreatment compositions
measured by Delta E
CottonCoffeeGrapeSpaghettiBloodDressingGrassMakeupMustardPie fillingTotal
CLOROX ™1.170.9125.344.259.479.297.9514.092.3974.87
SHOUT ™0.880.1822.783.258.497.257.3117.142.1169.41
Improved0.890.2520.183.438.755.225.4516.461.8962.52
Formulation
Comparison0.850.2620.724.458.897.637.7715.502.0768.14
Formulation

TABLE 8
Comparison of the removal of various types of stains on poly/cotton
cloth by several fabric pretreatment compositions measured by Delta E.
Poly CottonCoffeeGrapeSpaghettiBloodDressingGrassMakeupMustardPie fillingTotal
CLOROX ™1.471.6629.662.547.418.817.0210.643.0872.29
SHOUT ™1.31.2424.92.046.837.445.6810.72.3962.7
Improved1.411.0821.922.046.274.644.1910.782.4054.73
Formulation
Comparison1.380.7626.642.737.127.555.8111.052.1165.15
Formulation

Example 4

This Example compares the stain removal performance of detergent compositions of the present invention containing different peracid precursors.

Test fabrics, stains, and their application procedures were described in Example 3 above, with the addition of a dirty motor oil (DMO) stain to the stains tested here. The detergent formulation shown in Table 1 was prepared in bulk without the addition of the peracid precursor. Each of the different peracid precursors was then added to separate batches of this detergent formulation as follows: citric acid (Sigma Corp., St. Louis, Mo.) was added to a final concentration of 1 wt %. Adipic acid (Sigma Corp., St. Louis, Mo.) was added to a final concentration of 0.8 wt %. Tartaric acid (Sigma Corp., St. Louis, Mo.) was added to a final concentration of 1 wt %. One aliquot of the detergent formulation remained free of peracid precursor for comparison as a “no acid” added formulation.

After application of the stains, the swatches were allowed to rest overnight. Treatment conditions were as follows. For all treatments, 8 grams of each cleaner was dissolved in 1 liter of water. Water was at 104° F., 150 ppm hardness. Soaking time was sixty minutes. After the designated time, the buckets were drained, and each group of swatches was washed and dried as described in Example 1.

After drying, the swatches were evaluated for stain removal as described in Example 3. The results are shown in Tables 9 and 10 and FIG. 4. Tables 9 and 10 show the performance of each treatment type on each stain, reported as Delta E units. The “Total” column is the sum of the Delta E measurement across all stain types, indicating the overall stain removal performance of each treatment type. FIG. 4 is a graphical representation showing the sum of total Delta E for each stain for cotton plus the total Delta E for each stain obtained for both poly/cotton. These results demonstrate that all peracid precursor types tested improve the ability of the detergent formulations described in Table 1 to remove stains.

TABLE 9
Comparison of removal of stains on cotton cloth by detergent
formulations containing various or no peracid precursors as
measured by Delta E.
CottonCoffeeGrapeSpaghettiBloodDressingGrassMakeupMustardPie fillingDMOTotal
Citric Acid2.841.6419.314.829.869.2410.2119.284.0220.64101.85
No Acid2.811.5922.204.4410.4310.5310.2422.454.0019.53108.23
Adipic2.761.5121.054.399.818.968.6918.093.6819.5198.48
Acid
Tartaric2.671.5322.015.139.519.659.0219.453.8119.55102.34
Acid

TABLE 10
Comparison of removal of various types of stains on poly/cotton
cloth by detergent formulations containing various or no peracid
precursors as measured by Delta E.
Poly CottonCoffeeGrapeSpaghettiBloodDressingGrassMakeupMustardPie fillingDMOTotal
Citric Acid0.680.8223.930.867.145.206.0913.462.7629.2290.17
No Acid0.810.8223.531.736.975.715.5413.342.4629.5090.43
Adipic0.770.7821.531.157.275.245.9912.522.7429.2087.17
Acid
Tartaric0.690.8422.841.046.995.166.6312.833.0729.9089.98
Acid

Example 5

This example compares the stain removal performance demonstrated by formulations of the present invention containing adipic acid, tartaric acid, and L-tartaric acid and the commercial formulations SHOUT™, OXYPOWER™ and CLOROX™ Oxygen Action.

Test fabrics, treatment conditions, stains, and their application procedures were described in Example 3, with the difference that only spaghetti, blood, grass, makeup and mustard were tested in this Example. Adipic acid was tested in 1% and 0.8% concentrations in detergent compositions formulated as described in Example 4. Both the tartaric acid and the L-tartaric acid treatments consisted of the detergent formulation shown in Table 1 with the additives mixed to a final concentration of 1 wt. % tartrate.

After application of the stains, the swatches were allowed to age overnight. Treatment conditions were as follows. For all treatments, 8 grams was dissolved in 1 liter of water, except for CLOROX™, where 10 g was dissolved per liter of water. Water was at 104° F., 150 ppm hardness. Soaking time was sixty minutes. After the designated time, the buckets were drained, and each group of swatches was washed and dried as described in Example 1.

After drying, the swatches were evaluated for stain removal as described in Example 3.

The results are shown in Tables 11 and 12 and FIG. 5. Tables 11 and 12 show the performance of each treatment type on each stain, reported as Delta E units. The “Total” column is the sum of the Delta E measurement across all stain types, indicating the overall stain removal performance of each treatment type. FIG. 5 is a graphical representation showing the sum of total Delta E for each stain for cotton plus the total Delta E for each stain obtained for both poly/cotton. These results demonstrate that all types of peracid precursors, when used in the detergent formulations of Table 1 at the indicated concentrations, show increased stain removal relative to SHOUT™ Oxy Power and CLOROX™ Oxygen Action.

TABLE 11
Comparison of removal of various types of stains on cotton cloth
by detergent formulations containing various peracid precursors,
compared with SHOUT ™ Oxy Power and
CLOROX ™ Oxygen Action, as measured by Delta E.
CottonSpaghettiBloodGrass MakeupMustardTotal
SHOUT ™21.954.4119.1113.4814.5373.48
Oxy Power
CLOROX ™23.575.6819.6114.0413.6576.54
Oxygen Action
1% Adipic20.634.4910.036.8412.2354.21
0.8% Adipic20.584.4110.107.2412.2654.60
1% Tartaric21.514.4310.337.2912.5256.06
1% L-tartaric20.644.4610.567.1312.5855.37

TABLE 12
Comparison of removal of various types of stains on poly/cotton
cloth by detergent formulations containing various peracid
precursors, compared with SHOUT ™ Oxy Power and
CLOROX ™ Oxygen Action, as measured by Delta E
Poly CottonSpaghettiBloodGrass MakeupMustardTotal
SHOUT ™26.061.5917.3512.4211.3668.77
Oxy Power
CLOROX ™29.592.0918.0612.2212.1374.09
Oxygen Action
1% Adipic24.301.506.595.6310.3648.39
0.8% Adipic24.071.536.595.4211.1648.76
1% Tartaric24.301.436.765.6610.9449.09
1% L-tartaric24.981.547.345.9210.5250.30

Example 6

This example compares the dye fading performance demonstrated by formulations of the present invention containing adipic acid and tartaric acid, compared with the Comparison Formulation and commercial formulations SHOUT™ Oxypower, TIDE™ With Bleach and CLOROX™ Oxygen Action.

Pre-dyed test fabrics were obtained from Testfabrics, Inc., and consisted of swatches dyed with the following industry standard dyes: Acid Blue 113 on Polyamide, Direct Blue 71 on cotton, Reactive Blue 225 on cotton, Reactive Brown 7 on cotton, Sulphur Blue 19 on cotton, Direct Blue 1 on cotton, Direct Red 80 on cotton, and Acid Red on Nylon. Adipic acid was added to the Comparison Formulation to a final weight percent of 1%. Tartaric acid was added to the Comparison Formulation at a final weight percent equivalent to 1 wt % tartrate.

Treatment conditions for the dyed swatches were as follows. For all treatments, 8 grams of each cleaner was dissolved per 1 liter of water, except for CLOROX™, where 10 g was dissolved per liter of water. Water was at 104° F., 150 ppm hardness. Soaking time was sixty minutes. After the designated time, the buckets were drained, and each group of swatches was washed and dried as described in Example 1.

After drying, the swatches were evaluated for dye removal. The color difference was described as a Delta E value as described in Example 3. The smallest color difference has the smallest Delta E value, i.e. the lower the Delta E, the less fading observed. Delta E values reported are relative to dyed, non-treated cloth.

The results are shown in Table 13 and FIG. 6. Table 13 shows the fading performance of each treatment type for each dye, reported as Delta E units. The “Total” column is the sum of the Delta E measurement across all dye types, indicating the overall dye fading performance of each treatment type. FIG. 6 is a graphical representation showing the sum of total Delta E for each dye type. These results demonstrate that the addition of peracid precursors adipic acid and tartaric acid to the Comparison Formulation show only a small increase of dye fading relative to the Comparison Formulation, and cause less fading than TIDE™ with Bleach.

TABLE 13
Comparison of dye fading by detergents containing various
peracid precursors, compared with the Comparison
Formulation, SHOUT ™ Oxy Power, TIDE ™ With
Bleach and CLOROX ™ Oxygen Action,
as measured by Delta E
DirectReactiveReactiveSulphurDirectDirect
AcidBlue 71Blue 225Brown 7Blue 19Blue 1Red 80
Blue 113ononononononAcid Red
on Polyamidecottoncottoncottoncottoncottoncottonon NylonTotal
CLOROX ™0.590.960.812.083.512.967.480.9319.32
Adipic0.630.891.121.815.124.116.780.8221.28
Acid
Tartaric0.740.951.121.794.844.015.250.8819.58
Acid
Improved0.721.011.381.633.453.126.111.1318.55
Formulation
SHOUT ™0.580.471.142.214.112.126.320.9517.89
TIDE ™0.720.961.062.299.204.605.270.6024.71
with
Bleach

Example 7

This example compares the oxidation potential developed in water with the addition of the Comparison Formulation compared with the Improved Formulation. For both the Comparison Formulation and the Improved Formulation, 8 grams of each detergent composition was dissolved per 1 liter of water at 104° F., with 150 ppm hardness. The pH was approximately 10.8. Measurement of ORP (Oxidation Reduction Potential) in millivolts (mV) was made with an ORP electrode (Beckman Instruments, Fullerton, Calif.).

The results are shown in FIG. 7 which is a graphical representation comparing the ORP developed by both the Comparison Formulation and the Improved Formulation with curve fitting done exponentially. FIG. 7 demonstrates that the Improved Formulation increases ORP developed in water compared with the Comparison Formulation, indicating increased bleaching power.

Example 8

This example demonstrates the storage stability of particulate detergent formulations of the present invention. Two detergent formulations were prepared for stability testing having a composition described in Table 14. Additional sodium carbonate was included in one of the formulations to compensate for the absence of the sodium metasilicate metals protectant.

TABLE 14
Formulation for storage stability testing.
ComponentWt. %CAS #Name
Surfactant substrate36.75  497-19-8Sodium carbonate
Non-ionic2.95 68551-12-2GENOPOL LA060 ™;
surfactantlinear C (12-16)
alcohol ethoxylate (6
moles EO); Clariant
Corporation
Non-ionic0.65127036-24-2GENOPOL UD-030 ™;
surfactantC (11) alcohol
ethoxylate (3 moles
EO); Clariant
Corporation
Water soluble0.40 34590-94-8Dipropylene glycol
solventmethyl ether (1-(2-
methoxyisopropoxy)-2-
propanol); Lyonell
Alkaline peroxide56.58 15630-89-4Sodium percarbonate;
saltSolvay-Interox
Dispersive agent0.25 68479-09-4acrylic acid copolymer
˜4500 mole wt.,
sodium neutralized;
Rohm and Haas
Peracid precursor1.00  133-37-9Tartaric Acid;
American International
Metals1.42 6834-92-0Blue Meta; Sodium
protectant/dispersiveMetasilicate,
agentanhydrous 100.00; PQ
Corporation

The two formulations were prepared by blending a sodium carbonate surfactant substrate with a solution containing two non-ionic surfactants and a water-soluble substrate for less than one minute. The formulation was mixed for an additional 7 minutes to achieve a smooth, consistent material in which most of the liquid was absorbed by the powder. The remainder of the materials were then added and the mixture was blended for an additional 3.5 minutes until a uniform mixture was obtained.

Each of the two formulations were split into two batches that were measured for their available oxygen content and then stored at 50% humidity and either 72° F. or 96° F. for a period of 60 days. FIG. 8 shows the results of the stability testing as the exponential decay in the available oxygen content of the two formulations over the 60 day storage period.

Example 9

This example compares the reaction of two detergent formulations of the present invention having either an acidic or neutral source of peracid precursor. Two detergent formulations were prepared for testing having a composition described in Table 15.

TABLE 15
ComponentWt. %Name
Surfactant substrate31.5Sodium carbonate
Non-ionic surfactant2.75GENOPOL 26-L-45;
Clariant Corporation
Non-ionic surfactant1.0Acusol 445N
Water soluble solvent0.50Dipropylene glycol methyl
ether (1-(2-
methoxyisopropoxy)-2-
propanol); Lyonell
Alkaline peroxide salt62.0Sodium percarbonate;
Solvay-Interox

To this composition, tartaric peracid precursors were added in either an acidic form (tartaric acid) or a neutralized form (potassium sodium tartrate) to a concentration equivalent to 1.5 wt % acid (i.e. 1.5 wt. % tartaric acid and 2.15 wt. % sodium potassium tartrate). Both formulations were tested for their ability to clean stains on different fabrics in the testing protocols described in the preceding Examples. In each case, there was no significant difference in the cleaning ability of the two formulations having either an acidic or neutral form of the tartaric peracid precursor.

The foregoing discussion of the invention has been presented for purposes of illustration and description. The foregoing is riot intended to limit the invention to the form or forms disclosed herein. Although the description of the invention has included description of one or more embodiments and certain variations and modifications, other variations and modifications are within the scope of the invention, e.g., as may be within the skill and knowledge of those in the art, after understanding the present disclosure. It is intended to obtain rights which include alternative embodiments to the extent permitted, including alternate, interchangeable and/or equivalent structures, functions, ranges or steps to those claimed, whether or not such alternate, interchangeable and/or equivalent structures, functions, ranges or steps are disclosed herein, and without intending to publicly dedicate any patentable subject matter.