US 3159581 A
Description (OCR text may contain errors)
1964 F. L. DIEHL 7 3,159,581
' DETERGENCY COMPOSITION Filed April 15, 1962 -TRISOD|UM ETHANE-I-HYDROXY-l, l- DIPHOSPHONATE """SODTUM TRIPOLYPHOSPHATE CLEANING GRADE I l I l l l .9 L0 Ll L2 1.3 L4
DETERGENT USAGE EXPRESSED AS MILLIMOLAR CONCENTRATION OF BUILDER IN WASH WATER FIGURE 1 FORMULA 20% TALLOW ALKYL SULFATE 50% SODIUM TRl-POLYPHOSPHATE or MOLAR EQUIVALENT OF EHDP 6% SODIUM SILICATE SOLIDS 24 SODIUM SULFATE Francis L. Diehl INVENTOR.
ATTORNEY 3,159,5S1 DETERGENCY CUI /ilQSlTlON Francis lb. Dichi, Wyoming, Qhio, assignar to The Procter g Gamble Company, Cincinnati, @hio, a corporation of bio Filed Apr. 113, i962, Ser. No. 187,327 6 t'llaims. Cl. 252-152) This invention relates to detergent compositions, and more particularly detergent compositions containing socalled builder materials that serve to enhance the cleaning capacity of detergent compounds.
The use of builders as adjuncts to soap and synthetic detergents, and the property which some materials have of improving detergency levels of such detergent compounds are well known phenomena. The phenomena are widely appreciated but the exact behavior and mechanics of how builders perform their function has never been fully explained. While many explanations for the behavior of builders may be found, there still has not been determined a set of criteria which would permit one to accurately predict which compounds actually possess builder properties.
This may be explained, in part, by the complex nature of detergency itself and the countless factors which are conceptually involved. Among the many facets of built detergency systems in which builder materials are thought to have some effect are such factors as stabilization of solid soil, suspensions, emulsification of soil particles,the surface activity of the aqueous detergent solution, sol'ubilization of water-insoluble materials, foaming or suds producing characteristics of the washing solutions, peptization of soil agglomerates, neutralization of acid soil and sequestration of mineral constituents present in the washing solution tending to harden it. There might be mentioned many other areas in which a builder material might be of some assistance. The point is that no general basis has been found either as regards physical properties or chemical structure on which one might predict the behavior of chemical materials as overall detergency builders.
Among the builder materials described in the prior art, are water-soluble inorganic alkaline builder salts which are used alone or in combination. Examples are alkali metal carbonates, borates, phosphates, polyphosphates, bicarbonates and silicates.
Examples of organic builder compounds known heretofore and which also can be used alone and in. combination are alkali metal, ammonium or substituted ammonium aminopolycarboxylates, e.g., sodium'and potassium ethylenediaminetetraacetate, sodium and potassium N-(2- hydroxyethyl)-ethylenediaminetriacetate, sodium and potassium nitrilotriacetate and sodium, potassium and tri- United States Patent v sess builder properties to an exceptional degree.
3,l5d,58l Patented Dec. 1, 1964 ice builders and, in fact, form undesirable precipitates in the aqueous washing solution. Such lower forms include orthoand pyrophosphates.
- It has now been surprisingly discovered that watersoluble salts of ethane-bhydroxy-l,l-diphosphonate pos- Moreover, it has also been discovered that these compounds can be used to build detergent compositions containing a broad range of known detergent active materials. For instance, these compounds can build detergent compositions containing as active ingredients anionic, nonionic, ampholytic and zwitterionic detergent compounds.
It is, therefore, a primary object of this invention to provide new and improved builder compounds having increased efiiciency over previously known builders. Another object is to provide improved detergent compositions containing as the builder material, a water-soluble salt of ethane-l-hydroxy-l,l-diplrosphonate. A yet further object is to provide improved built detergent compositions in which the builder material is a water-soluble salt of ethane-bhydroxy-l,l-diphosphonate and which built compositions are surprisingly effective in cool Water washing situations.
Still further objects and the entire scope of applicability of the present invention will become apparent from the detailed description given hereinafter; it should be understood, however, that the detailed description and specific examples, while indicating preferred embodiments of the invent-ion, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
The attached drawing, FIGURE 1, is a graph showing washing grades obtained as a function of the molar concentration of two builder materials as hereinafter more fully described.
The water-soluble builder salts of this invention are derivatives of ethane -l-hydroxy-l,l-diphosphonic acid which has the following molecular formula CHSU a 2h hydrogens are replaced by sodium. Hence, the salt comethanolammonium N (2 hydroxyethyl)-nitrilodiacetate. Alkali metal salts of phytic acid, e.g.,' sodium phytate are also suitable asorganic builders.
An ever increasing interest in builder materials has resulted in an expanding list'of compounds which when used in conjunction'with known cleaning agents serve to enhance the cleaning performance of such detergents. This increased interest has brought about the fuller appreciation that improved builders are highly desirable to avoid certain limitations and disadvantages of prior art builder materials. I v
One of the more well known of the disadvantagesis associated with probably the most widely usedg roup of builder materials. This would be the series of condensed inorganic poly phosphate compounds such as alkali metal tripolyphosphates and higher condensed phosphates. These compounds have a strong tendency to hydrolyze when usedin detergent compositions into less condensed phosphorus compounds which are relatively inferior monly prepared is the trisodium salt, which gives a pH near 9.5 in distilled water. The anhydrous trisodium salt has the structure It crystallizes normally as the hexahydrate, which loses some water during air-drying to yield a mixture of the hexaand monohydrate averaging 3 to 4 molecules of water of hydration. It is much more stable toward hydrolysis than ordinary condensed polyphosphates.
While any alkali metal or ammonium or substituted ammonium salt form can be used as the builder in this invention, the tetrasodium salt, the trisodium salt and mixtures thereof are the preferred forms. Mixtures of the tetrasodium and trisodium salts give a pH in water solution from about 9.5 to 11.5. Each of the lesser neutralized forms such as monosodium and disodium derivatives or the free acid have comparable builder capacity to the trisodium and tetrasodium salt forms'provided that additional alkali is added to adjust the pH of the washing solution to about 9 to about 12. The standard alkaline materials can be used for this purpose, such as alkali metal silicates, phosphates, borates and carbonates.
3 Free alkali materials such as sodium and potassium hydroxides can also be used.
Hereinafter in this specification the novel builder compound is referred to as EHDP and is intended to broadly cover the acid as well as all of the various neutralized salt forms thereof.
As mentioned above, it has already been suggested to combine synthetic detergent compounds with various builder salts to produce built detergent compositions. As far as is known, however, no one prior to this invention has discovered the particular combination of compounds and proportions described herein that offer as advantages, stability against deterioration during storage and use, high detergent power, and outstanding performance in hard water. As illustrated hereinafter in more detail, the detergent compositions of this invention offer extraordinary results in the important area of whiteness maintenance or whiteness retention.
These and other advantages are obtained according to this invention by providing cleaning and laundering compositions consisting essentially of a synthetic non-soap detergent surfactant compound and as a builder, a watersoluble salt of ethane-l-hydroxy-l,l-diphosphonate, such as the sodium or potassium salts, the ratio by weight of the builder to the detergent surfactant compound being in the range of about 1:2 to about 10:1, said composition providing in solution a pH of about 9 to 12. The preferred ratio of diphosphonate builder to said detergent surfactant compound is in the range of about 1:1 to about 5:1 and the optimum pH range is 9.5 to 11.5.
In view of the complex functions and behavior of builders and built systems, it is difiicult to explain exactly why superior results are obtained with an EHDP-built detergency system, be it granular, tablet or liquid.
The fact is, however, that now it surprisingly has been discovered that the complex formed between EHDP and the hardness imparting ingredients of water possesses builder effectiveness per se while the complex formed between sodium tripolyphosphate and the hardness imparting ingredients does not possess such capabilities. This phenomenon has not been known or described prior to this invention.
One possible explanation of the superior laundering performance of EHDP-built compositions over STP-built compositions may lie in the different behavior of the complexes which each builder forms with the hardness imparting ingredients contained in the water. The EHDP complex forms a highly soluble compound in water whereas the ST? complex forms a sodium salt which is substantially less soluble and tends to precipitate out on the articles being washed. The insoluble complex which precipitates out on the articles firmly adheres to such articles. During the rinsingcycle the precipate is ex posed to an excess of hardness imparting ingredients which proceed to react with the precipitated complex salt and transform it to an even more insoluble adherent form. Thus, the washing process can be complicated by the complex forming properties of an STP built detergent composition where the active STP builder is consumed and bound up in an insoluble complex. In contradistinction, EHDP when used as a detergency builder is bound up in a solubiliz ed form which allows it to participate in and carry on the many other builder functns.
It is not intended that the invention should be limited by the foregoing since it is proffered merelyas one possible explanation for the superior performance obtained by EHDP over STP in the areas of cleaning, whiteness and whiteness maintenance.
Among the synthetic organic detergent surfactant compounds which can be successfully built by EHDP and which are clearly within the contemplation of this invention are the following examples:
(a) Anionic synthetic detergents: This class of synthetic detergents can be broadly described as the watersoluble salts, particularly the alkali metal salts of organic sulfuric reaction products having in their molecular structure an alkyl radical containing from about 8 to about 22 carbon atoms and a radical selected from the group consisting of sulfonic acid and sulfuric acid ester radicals. (Included in the term alkyl is the alkyl portion of higher acyl radicals.) Important examples of the synthetic detergents which form a part of the preferred compositions of the present invention are the sodium alkyl sulfates, especially those obtained by sulfating the higher alcohols (C C carbon atoms) produced by reducing the glycerides of tallow or coconut oil; sodium or potassium alkylbenzenesulfonates, in which the alkyl group contains from about 9 to about 15 carbon atoms, especially those of the types described in United States Letters Patent Numbers 2,220,099, and 2,477,383; sodium alkylglycerylethersulfonates, especially those ethers of the higher alcohols derived from tallow and coconut oil; sodium coconut oil fatty acid monoglyceride sulfates and sulfonates; sodium or potassium salts of sulfuric acid esters of the reaction product of one mole of a higher fatty alcohol (e.g., tallow or coconut oil alcohols) and about 1 to 6 moles of ethylene oxide; sodium or potassium salts of alkylphenol ethylene oxide ether sulfate with about 1 to about 10 units of ethylene oxide per molecule and in which the alkyl radicals contain about 9 to about 12 carbon atoms; the reaction product of fatty acids esterified with isethionic acid and neutralized with sodium hydroxide, where, for example, the fatty acids are derived from coconut oil; sodium or potassium salts of fatty acid amide of a methyltauride in which the fatty acids, for example, are derived from coconut oil; and others known in the art, a number being specifically set forth in United States Letters Patent Numbers 2,486,921, 2,486,922 and 2,396,278.
(b) Nonionic synthetic detergents: This class of synthetic detergents may be broadly defined as compounds aliphatic or alkyl aromatic in nature which do not ionize in water solution.
For example, a well known class of nonionic synthetic detergents is made available on the market under the trade name of Pluronic. These compounds are formed by condensing ethylene oxide with an hydrophobic base formed by the condensation of propylene oxide with propylene glycol. The hydrophobic portion of the molecule which, of course, exhibits water insolubility has a molecular weight of from about 1200 to 2500. The addition of polyoxyethylene radicals to this hydrophobic portion tends to increase the water solubility of the molecule as a whole and the liquid character of the product is retained up to the point where polyoxyethylene content is about 50% of the total weight of the condensation product.
Other suitable nonionic synthetic detergents include:
(1) The polyethylene oxide condensates of alkylphenols, e.g., the condensation products of alkylphenols or dialkylphenols wherein the alkyl group contains from about 6 to 12 carbon atoms in either a straight chain or branched chain configuration, with ethylene oxide, the said ethylene oxide being present in amounts equal to 10 to 25 moles of ethylene oxide per mole of alkylphenol. The alkyl substituent in such compounds may be derived from polymerized propylene, diisobutylene, n-octene, or
'n-nonene, for example.
(2) Those derived from the condensation of ethylene oxide with the product resulting from the reaction of propylene oxide and ethylenediamine. For example, compounds containing from about 40% to about polyoxyethylene by weight and having a molecular weight of from about 5000 to about 11,000 resulting from the (3) The condensation product of aliphatic alcohols having from 8 to 18 carbon atoms, in either straight chain or branched chain configuration, with ethylene oxide, e.g., a coconut alcohol-ethylene oxide condensate having from to 30 moles of ethylene oxide per mole of coconut alcohol, the coconut alcohol fraction having from 10 to 14 carbon atoms.
(4) Long chain tertiary amine oxides corresponding to the following general formula, R R R N O, wherein R is an alkyl radical of from about 8 to 18 carbon atoms, and R and R are each methyl or ethyl radicals. The arrow in the formula is a conventionalrepresentation of a semi-polar bond. Examples of amine oxides suitable for use in this invention include dimethyldodecylarnine oxide, dimethyloctylamine oxide, dimethyldecylamine oxide, dimethyltetradecylamine oxide, dimethylhexadecylamine oxide.
(5) Long chain tertiary phosphine oxides correspond ing to the following general formula RRR"P O wherein R is an alkyl, alkenyl or monohydroxyalkyl radical ranging from 10 to 18 carbon atoms in chain length and R and R are each alkyl or monohydroxyalkyl groups containing from 1 to 3' carbon atoms. The arrow in the formula is a conventional representation of a semi-polar bond. Examples of suitable phosphine oxides are:
about 8 to 18 carbon atoms, and an'anionic water solubilizing group, e.g., carboxy, sulfo, or sulfato. Examples of compounds falling Within this definition are sodium-3- dodecylaminopropionate and sodium-3-dodecylaminopropanesulfonate.
(d) Zwitterionic synthetic detergents: This class of synthetic detergents can be broadly described as'derivatives of aliphatic quaternary ammonium compounds, in which the aliphatic radical may be straight chain or branched andwherein one of the aliphatic substituents contains from about 8 to 18 carbon atoms and one contains an anionic water solubilizing group, e.g., car'boxy,
life of delicate fabrics and materials (synthetics such as nylon, Dacron as well as woolens and silks) which cannot tolerate the harsh treatment of severe hot water washing. It is well known that certain fabrics have a pronounced tendency to shrink, wrinkle, or draw up when washed in very hot water. In addition to the fabrics and materials already mentioned, other wash-wear fabrics such as 'Creslan, resin-treated cottons and fabrics made from Kodel polyester fibers are also adversely affected when washed at hot water temperatures.
The anionic, nonionic, ampholytic and zwitterionic detergent surfactants mentioned above can be used singly or in combination in the practice of the present invention. The above examples are merely specific illustrations of the numerous detergents which can find application within the scope of thisinvention.
'T he foregoing synthetic organic detergent compounds can be built into any of the several commercially desirable composition forms, for example, granular, fiake, liquid and tablet forms.
Granular detergent compositions according to one embodiment of this invention can contain the EHDP builder and the detergent active in the ratio of about'lzZ to about 10: 1. The preferred ratio of builder to active is about 1:1 to aboutSzl.
Another embodiment of this invention is a liquid detergent composition also containing the EHDPbuilder and the detergent active in the ratio of about 1:2 to about about 1:2 to about 3:1.
10: 1; On the other hand, the preferred ratio and optimum results in such compositions are obtained when Ei-IDP and the detergent active are mixed in ratiosby weight of The detergent compositions described by this invention employing EHDP as a builder can have special and unusually outstanding applicability in the area of built liquid detergents. This area presents special problems to the 'formulator in view of the peculiarities inherent in aqueous systems and the special requirements of solubility of the 40. ingredients and, more especially, their stability in such mediums. It iswell known, for instance, that sodium tripolyphosphate, while outstanding in its behavior in granular compositions, is generally regarded as being unsuited for built liquid detergents. It has a strong propensity to hydrolyze into orthoand pyro-forrns of phosphates. Thus, as a practical consideration there has been a necessity ofresorting to'alkali metal pyrophosphates such as Na P O or K P O in order to prepare a built liquid detergent. This has been true notwithstanding the known inferiority of pyrophosphates to sodium tripolyphosphate, for example, as a builder for heavy duty detergency.
In view of the increasing acceptance by the general I public of built liquid detergents for virtually all Washing sulfo or sulfato. Examples of compounds falling within 1 this definition are 3-(N,N-dimethyl-N-hexadecylarnmohim-propane and 3 (N,N-dirnethyl-N-hexadecylammonio) Z-hydrbxypropyane-l-sulfonate.
It has been unexpectedly discovered that the zwitterronlc detergent surfactant compounds mentioned above when and cleaning situations including laundering and dishwashing, it is a very significant contribution of this invention that an improved built liquid detergent product is :made possible that will provide detergency levels comparable to and in some aspects superior to a sodium tripolyphosphate built liquid'product without the troublesome stability problem presented by sodium tripolyphosphate.
Most of the built liquid detergents commercially available at the present time are either water based or have a mixture of water and alcohol as the liquid vehicle. Such vehicles can be employed in formulating an EHDP built A liquid detergent without fear of encountering stability Washing-water which general household laundering situae tions have required the past. Suchf'conventional wash-f I ingtemperatureslare in the range offlllSOiYFgloabout 140 Fraud 14 5 Cool water as usedfher ein is in the temperature rangeofabout 40? F; to about 100? F. I I V V V V V there will aofte'n be added in minor amounts materials A detergent formul'ationgpossessing high cleansing per formance at such low temperatures ha s -obvious advan- 'which make the productmore effective or more attractive. The following are mentioned by way of example. A sol- :1uble sodium vcarho);ymethylcellulose may be added, in
problems. Accordingly, a'sample'built detergent composition' of this invention can consist essentially of EHDP and a detergent surfactant in: the ratios above described and the balance beinga vehiclemediurn, for example, water, a, g V "water-alcohol mixture, nonionic. surfactant compounds, 7'0 a In a finished detergent formulation ofthis invention F minor amounts to inhibit soil redeposition. A tarnish inhibitor such as benzotriazole or ethylenethiourea may also be added in amounts up to about 2%. Fluorescers, perfume and color while not essential in the compositions of the invention, may be added in amounts up to about 1%. An alkaline material or alkali such as sodium hydroxide or potassium hydroxide can be added in minor amounts as supplementary pH adjusters. There might also be mentioned as suitable additives moisture, brightening agents, sodium sulfate, and sodium carbonate.
Corrosion inhibitors generally are also added. Soluble silicates are highly effective inhibitors and can be added to certain formulas of this invention at levels of from about 3% to about 8%. Alkali metal, preferably potassium or sodium, silicates having a weight ratio of SiO M O of from 1.0:1 to 28:1 will be used. M in this ratio refers to sodium and potassium. A sodium silicate having a ratio of SiO :Na O of about 1.6:1 to 2.45:1 is especially pre ferred for economy and effectiveness.
In the embodiment of this invention which provides for a built liquid detergent, a hydrotropic agent may at times be found desirable. Suitable hydrotropes are water-soluble alkali metal salts of toluenesulfonate, benzenesulfomate, and xylenesulfonate. The preferred hydrotropes are the potassium or sodium toluenesulfonatcs. The hydrotrope salt may be added, if desired, at levels of to about 12%. While a hydrotrope will not ordinarily be found necessary, it can be added if so desired for any reason such as to produce a product which retains its homogeneity at a low temperature.
The following compositions will serve to illustrate this facet of the invention. gent formulation according to this invention has the following composition, in which the percentages are by weight.
6.0% sodium dodecylbenzenesulfonate (the dodecyl radical being a polypropylene, predominantly tetrapropylene averaging 12 carbon atoms) 6.0% dimethyldodecylamine oxide 20.0% trisodium ethane-l-hydroxy-1,1-diphosphonate 8.0% potassium toluenesulfonate 3.8% sodium silicate (ratio SiO :Na O of 2.45: 1)
0.3% carboxymethyl hydroxyethyl cellulose Balance water 7 Performance of this detergent composition was excellent in laundry tests as well as dishwashing evaluations. Its resistance to hydrolysis made possible cleaner washes as well as longer shelf life since EHDP builder remained in its active form through the complete washing cycle notwithstanding the large amounts of water present.
An excellent granular detergent composition giving outstanding cleaning and whiteness maintenance results in washing situations was prepared-having the following ingredients in the percentages indicated:
17.5% sodium dodecylbenzenesulfonate (dodecyl group derived from tetrapropylene) 2.0% potassium toluenesulfonate 47.0% trisodium ethane-l-hydroxy-l,l-diphosphonate 6.0% sodium silicate (ratio siO zNa O of 2:1)
13.8% sodium sulfate 2.7% coconut fatty acid ethanolamide Balance moisture A granular detergent composition was prepared having Condensation products of ethylene oxide with a hydrophobic oase formed by the condensation of propylene oxide avitlz propylene glycol and having molecular weights of approximately 3000 and 8000 respectively.
Washing performance characteristics of this composition are exceptionally good from the point of view of general cleaning and whiteness maintenance performance.
An excellent built liquid deter Another highly effective granular detergent offering equally good laundering performance in the area of whiteness, cleaning and whiteness maintenance was prepared having the following formulation:
20.0% sodium dodecylbenzenesulfonate (dodecyl group derived from tetrapropylene) 2.0% potassium toluenesulfonate .5 trichlorocarbanilide (as a bacteriostat) 30.0% trisodium ethane-1-hydr0x -1,1-diphosphonate 6.0% sodium silicate (ratio SiO :Na O of 2:1)
:and one deep rinse) and then dried.
32.3% sodium sulfate 1.6% coconut fatty acid ethanolamide 1.6% miscellaneous 6.0% water An effective cool water built liquid detergent which also performs exceptionally well as a heavy duty detergent composition, especially in the areas of cleaning and whiteness maintenance, has the following composition:
12.0% 3(N,N-dimethyl-N hexadecylammonio) 2 hydroxypropane-l-sulfonate 20.0% trisodium ethane-l-hydroxy-1,1-diphosphonate 3.8% sodium silicate (SiO :Na O=1.6:1)
8.5% potassium toluenesulfonate .3% sodium carboxymethyl hydroxyethyl cellulose .12% fluorescent dye .15 perfume .02% benzotriazole 55.11% water An effective cool water built granular composition according to this invention has the following composition:
17.0% 3-(N,N dimethyl N hexadecylammonio) propane-l-sulfonate 45.0% trisodium ethane-l-hydroxy-1,1-diphosphonate 6.0% sodium silicate (Na O:SiO =1:2.5)
.3% sodium carboxymethyl cellulose 28.0% sodium sulfate 3.5% water Balance miscellaneous Excellent whiteness maintenance and cleaning performance results are obtained by laundering with this composition.
Wash-wear tests using standardized detergent compositions, described below, were conducted to determine the relative builder effectiveness of EHDP. Sodium tripolyphosphate was used as a standard builder due to its current wide use in the industry. Surprisingly, EHDP consistently performed as a superior builder in virtually all cleaning characteristics which were graded.
The test employed was conducted in the following manner. White dress shirts, cotton T-shirts and other fabrics were distributed among various individuals. Each dress shirt and T-shirt was worn for one normal working day under uniform conditions and the other articles were used for their generally intended purposes. The soiled clothes and fabrics were then washed in an automatic agitating type washer, for a period of ten minutes, with detergent solutions at F. temperature. The wash water was at a pH of 10 and had a hardness of 7 grains per gallon.
After washing, the clothes were rinsed (six spray rinses (No fluorescers or bleaches were used).
Direct comparisons were made by a panel of five graders between pairs of, shirts and fabrics worn and soiled by the same individual. The dress shirts, T-shirts' and other fabrics used, were graded on the degree of whiteness and the degree of cleaningobtained, paying particular attention on this latter feature to the dress shirt collars and formulation scored, in all cuffs. For purposes of this invention, the term cleaning or cleanliness measuresthe ability of a washing comures the ability of a cleaning composition to whiten areas which are, only slightly or moderately soiled. Clean washcloth size swatches of cotton terry cloth and muslin were washed along with the soiled clothes to arrive at an independent evaluation of the whiteness maintenance ,or whiteness retention property of the particular cleaning compositions. The relative cleaning eiiectiveness of each detergent composition in each area was graded on a raw score under U.V.-free'artificial light, averaged, and then translated onto a -10 scale wherein the highest grade of was assigned to the relatively best performance obtained. Generally a grade-of 0 to l was indicative of washing results obtained when soiled clothes were washed in water alone without any detergent composition at all. Intermediate grades accordingly represented relative performances between these limits. p
The detergent composition employed during the tests consisted of 20% sodium tallow alkyl sulfate asthe detergent active, (the alkyl chain length distribution of tallow alkyl sulfate was approximately 66% C 30% C and 4% others), 50% sodium tripolyphosphate or a molar equivalent of EHDP, 6% sodium silicate and 24% sodium sulfate. On a total basis of 100%, a molar equivalent of 50% sodium tripolyphosphate is 37.0% EI-IDP (as trisodium salt). In this instancewhen EHDP was employed,
the difference between the lesser percentage of EHDP 10 even as the molar concentration of the STP builder and theEHDP builder was'decreased from about 1.4 to .9 gram moles l0- per liter, and simultaneously as the weightconcentr-ation of EHDP (as trisodiurn salt) was decreased from 037% to .024% and of STP was decreased from .()50% to 033%. This is evidence of the fact that EHDP is a very markedly more eflicient builder at lower concentrations thanis STP. This constitutes an important novel feature of this invention for according to this invention it is now possible for consumers to obtain superior washing performance in' household washing situations with EHDP-built formulations using considerably less of an EHDP builder material than would generally be thought necessary based on conventional builders and STP can be made up with 13% water. The pH of the washing solution was 10.
The grading results obtained in the manner described above were charted on a graph and are here presented in FIGURE 1. It will be notedfrom this figure that the dress shirt and T-shirt whiteness and cleaning results obtained by the EHDP formulation are surprisingly and markedly superior to sodium tripolyphosphate (STP) over virtually the full range of molar concentrations tested. It will also be noted that the whiteness mainte- Y nance results obtained by washing with the. compositions of this invention are greatly improved over those obtained by washing with a conventional builder material such as sodium tripolyphosphate. Whiteness maintenance measures the capacity of the washing composition to prevent the redeposition of .soil which has been removed from soiled areas of the washed articles. fact, the prevention of redeposition of suspended soil in washing processes is so important that it frequently is characterized as a fundamental phenomenon, on a par with the removal of soil itself from the fabrics. .It is, therefore, a valuable and unpredictable feature'of the compositions of the present invention that they are superior to conventional builders in this important area of detergency. The concentrations of FIGURE 1" are millimoles of EHDP or STP per liter of wash water. concentration of the builder detergent in solution was varied from about 033% to .050% of STPiand..024% to 037% of EHDP (as trisodiumsalt) to provide the molar concentration of builder in the wash water set of'the builder materials. p I
As-seen in FIGURE 1, the articles washed with the EHDPabuilt formulation scored :grades in the range of 6.7 tof9.7 in each characteristic'that was graded. On
the ,otherhanifthe. article's washed with *the STP-builtbut one instance, grades rang ;ingfrom 0.5 to about 7.
In point of t dimethyl-N-hexadecylammonio) 2 hydroXypropane-lsuch as STP. Wash-wear tests have established that washing performances obtained with a 0.03% concentration of EHDP in a washing solution can only be obtained with STP-built compositions when about double the EHDP concentration is employed or in the neighborhood of .06 to .07% of STP. This increased efiiciency is illustrated by FIGURE l where it will be noted that the grading curves for EHDP are relatively flat over the range of concentrations tested whereas the grading curves for STP fall off precipitously as the concentration of builder in 'the washing solution is decreased toward the left hand'side of the graph. As established earlier in this specification, the exceptional builder property of EHDP could not have been predicted from any data previously known.
The foregoing description of the invention has been presented describing certain operable and preferred em.- bodiments. It is not intended that the invention should be'so limited since variations and modifications thereof will be obvious to those skilled in the art, all of which are within the spirit and scope of this invention.
What is claimed is: 1
1. An improved cleansing and laundering composition consisting essentially of a water-soluble trisodium salt of ethane-l-hydroxy-l,l-diphosphonate as a builder and. an organic water-soluble non-soap synthetic detergent surfactant having pronounced detergent power selected from the group consisting of anionic, nonionic, zwitterionic, ampholyrtic detergent surfactants, and mixtures thereof, the ratio, by weight, of said disph'osphonate builder to said detergent surfactant being in the range of about 1:2 to about 10:1, said composition providing in aqueous solution a pH between about 9 and about 12.
2. The composition of claim 1 wherein the ratio, by
consisting essentially of a water-soluble trisodiurn salt of eth-ane-l-hydroXy-l,l-diphosphonate as'a builder and as a detergent active an organic water-soluble zwitterionic detergent surfactant having pronounced detergent power selected from the group consisting of 3-(N,N-dimethyl- N-hexadecylammouio)-propane-l-sulfonate, and 3-(N,N-
sulfonate, the ratio of said diphosphonate builder to said detergent active being in the range of about 1:2 to about ;10:1, said composition providing in aqueous solution a pH between about 9.and about 12.
5. An improved cleansing and laundering composition consisting essentially of awater-soluble trisodium salt of ethane-l-hydroxy-1,1-diphosphonateas a builder and as a detergent active. an anionic Water-solublealkali metal salt Yof an organic sulfuric reaction product having in its jmolccular structure an alkyl radical having 8 to '22 carbon atoms and'a radical selecte d from the group consisting of Itwill benoted from FIGURE 1 that this snperiority i of *the .EHDP formulation was l, consistently maintained sulfonicacid and sulfuric acid/ester radicals, the ratio of said diphosphonate builder to said detergentfactive being inthe range of 5 about.-1. 2 to about 10:1,. said.
composition providing in aqueous solution a pH between References Cited in the file of this patent abOutg UNITED STATES PATENTS 6. The cleansing and laundering compositlon of claim 5 wherein the anionic detergent active is selected from 2,491,920 Emsberger 1949 the group consisting of alkali metal alkyl sulfates in 5 which the alkyl substituent contains from about 8 to 18 FOREIGN PATENTS carbon atoms, alkali metal alkylbenzenesulfonates in 1,010,965 Germany May 8, 1956 which the alkyl group contains from about 9 to about 15 1,072,346 Germany Dec. 31, 1959 carbon atoms, and alkali metal alkylglycerylethersulfo- 1,082,235 Germany May 25, 1960 mates in which the alkyl is derived from the higher alcohols 10 1 107,207 Germany May 25, 19 1 obtained from tallow and coconut oil.