US 3817863 A
Description (OCR text may contain errors)
3,817,863 DETERGENT FORMULATIONS Chung Yu Shen, St. Louis, Mo., assignor to Monsanto Company, St. Louis, M0. N Drawing. Filed Aug. 23, 1972, Ser. No. 283,013 Int. Cl. C11d 3/20 US. Cl. 252-89 5 Claims ABSTRACT OF THE DISCLOSURE Detergent formulations comprising a surfactant and tetrasodium or tetrapotassium tetrahydrofuran-2,2,5,5- tetracarboxylate or hydrates thereof as a builder exhibit effective cleaning action.
BACKGROUND OF THE INVENTION Detergent formulations generally comprise a surfactant in combination with a material which serves as an adjuvant, reinforcer, supplement, augmentor, potentiator and/ or benefactor, such material being generally referred to as a detergency builder.
The selection of materials which are effective detergency builders is a complex matter empirical in nature and not accurately predictable from known characteristics of the materials.
Many known materials employed as detergency builders have been characterized by high phosphorus content such as the alkali metal tripolyphosphates. In view of suggestions by some researchers that phosphorus containing materials may accelerate eutrophication processes in some aquatic environments where other factors essential to the eutrophication process are present, extensive interest has developed in providing detergent formulations free of phosphorus or characterized by a significantly reduced phosphorus content.
SUMMARY OF THE INVENTION It is an object of this invention to provide novel detergent formulations containing a novel phosphorus free detergency builder. Generally, the formulations of this invention comprise a detergent surfactant in combination with tetrasodium or tetrapotassium tetrahydrofuran-2,2, 5,5-tetracarboxylates or their hydrates. The formulations of this invention will be understood from the following description of the preferred embodiments.
DESCRIPTION OF THE PREFERRED EMBODIMENTS The essential ingredients of the formulations of this invention are a detergency builder and a surfactant.
The builders characterizing the formulations of this invention are tetra alkali metal 2,2,5,5 tetracarboxylates represented by the formula MOOO/ \COOM COOM United States Patent "ice cyanotetrahydrofuran is known to those skilled in the art, its preparation being described, for example, in US. Pat. 3,317,567. The use of the colorless crystalline form of the builder such as obtained by addition of the nitrile to an aqueous solution of sodium hydroxide or potassium hydroxide wherein the concentration of the base is maintained in excess of that stoichiometrically required to hydrolyze the nitrile is preferred. (If the carboxylate is prepared by addition of the hydroxide to the nitrile, undesirable color formation occurs.)
The detergent formulations of this invention will contain from 1 to by weight, preferably from 5 to 50% by weight, of the tetra alkali metal tetrahydrofuran-2,2, 5,5-tetracarboxylate. These compounds can be utilized as the sole detergency builder or employed in combination with other known detergency builders such as water soluble inorganic builder salts, for example, alkali metal carbonates, borates, phosphates, polyphosphates, bicarbonates, silicates or organic builders such as salts of nitrilotriacetic acid, phytic acid, sodium citrate, water soluble polymeric polycarboxylates such as described in US. Pat. 3,308,067 and the like.
The detergent formulations will additionally contain at least 8% by weight of a surfactant. Any of the numerous well known anionic, nonionic, zwitterionic or ampholytic surfactants can be employed.
Examples of suitable anionic surfactants include alkyl ether sulfonates, alkyl sulfates, acyl sarcosinates; acyl esters of isocyanates, acyl N-methyl taurides, and alkyl aryl sulfonates. The foregoing materials are used in the form of their water-soluble sodium, potassium, ammonium and alkyl ammonium salts. Specific examples include sodium lauryl sulfate; sodium N- methyl lauryl tauride; sodium dodecyl benzene sulfonate; and triethanol amine undecanol benzene sulfonate.
Examples of suitable nonionic detergents include alkyl phenol and alcohol alkoxylates including condensates of l-decanol or l-undecanol with from 3 to 5 molecular proportions of ethylene oxide; condensates of monohydroxy or polyhydroxy alcohols such as oleyl alcohol or l-tridecanol with from 9 to 15 molecular proportions of ethylene oxides; alkyl internal vicinal dialkoxy or hydroxy alkoxy compounds as described in US. patent application Ser. No. 197,504 filed Nov. 10, 1971 and copending herewith; and condensates of alkylene oxides with organo amines, for example, ethylene diamine and amides such as N-octadecyl diethanol amide.
Suitable ampholytic surfactants include the amido alkene sulfonates such as sodium C-pentadecyl, N-methyl amido ethyl sulfonate potassium C-octyl N-naphthalene amido propyl sulfonate; ammonium C-decyl, N-cyclo propyl amido butyl sulfonate, and aliphatic amine derivatives in which the aliphatic substituent contains an anionic watersolubilizing substituent such as a carboxy, sulfo, phosphato, or phosphino group, for example, sodium-3-dodecyl amino propionate and sodium-3-dodecyl amino propane sulfon'ate.
Examples of zwitterionic surfactants include derivatives of quaternary ammonium phosphonium and sulfonium compounds such as 3 (N,N-dimethyl-N-hexadecyl ammonio) propane-l-sulfonate and 3-(N,N-dimethyl-N-hexadecyl ammonio-Z-hydroxy propane-l-sulfonate).
It will be understood that the above examples of sup plementary surfactants are by no means comprehensive. Numerous other surfactants are known to those skilled in the art and are set forth in such familiar references as Surface Active Agents by A. M. Schwartz and James W. Perry. It will be further understood that the use of such surfactants will be in accordance with conventional, well-understood practices of detergent formulation. For example, cationic and anionic detergents will not normal- 1y be employed in combination due to recognized problems of precipitation of insoluble products.
In accordance with general practice, the ratio of the detergency building components to the surfactant components will be in the range of from 1:2 to about 12:1 by Weight.
In addition to surfactant and builder components, the detergent formulations may contain fillers such as sodium sulfate and minor amounts of bleaches, dyes, optical brighteners, soil anti-redeposition agents, perfumes and similar conventional detergent formulation additives.
The invention is further illustrated by the following examples wherein all parts and percentages are by weight unless otherwise indicated.
EXAMPLE I About 172 grams of 2,2,5,S-tetracyanotetrahydrofuran is added to 1000 grams of a stirred 27% by weight aqueous sodium hydroxide solution maintained at 75 C. and the reaction medium is maintained at such temperature until NI-I evolution ceases.
Colorless crystalline product is separated by filtration, washed with a saturated solution of the salt and dried.
The product, after drying at 60 C., is analyzed as being tetrasodium-2,2,5,S-tetrahydrofurantetracarboxylate containing 1.5-2 moles water of hydration. Drying the product for about 4 hours at 200 C. yields anhydrous tetrasodim-2,2,5,5-tetrahydrofurantetracarboxylate.
EXAMPLE II The procedure described in Example I above is repeated with the exception that potassium hydroxide is substituted for sodium hydroxide. The corresponding tetrapotassium salt products are obtained.
EXAMPLE III Detergent formulations containing 12% linear alkylbenzene sulfonate having an average-alkyl chain length of about 12 carbon atoms; from 5 to 75% of the product produced by the procedures of Examples I and H; 12% sodium silicate having an SiO to Na O ratio of about 2:4; and a quantity of sodium sulfate sufiicient to equal 100% are found, in conventional laundry operations, to clean soiled samples of cotton and polyester/cotton broadcloth substantially better than otherwise identical formulations containing no builder.
EXAMPLE IV The tests of Example III above are repeated using a detergent formulation in which Neodol 45-11 (a nonionic surfactant which is an adduct of a modified oxo type C -C alcohol with an average of 11 moles of ethylene oxide) is substituted for the alkylbenzene sulfonate. Comparable results are obtained.
EXAMPLE V The tests of Example III are repeated with a detergent formulation wherein sodium hydroxyalkyl (C -C alkyl chain length) N-methyl laurate; an ampholytic surfactant, is substituted for the alkylbenzene sulfonate. Comparable results are obtained.
EXAMPLE VI The tests of Example III are repeated with a detergent formulation wherein cocodimethylsulfopropylbetaine, a zwitterionic surfactant is substituted for the alkylbenzene sulfonate. Comparable results are obtained.
What is claimed is:
1. A detergent composition consisting essentially of at least 8% by weight of a surfactant selected from the group consisting of anionic, nonionic, zwitterionic, ampholytic and amphoteric surfactants and from 1% to by weight of a detergency builder compound represented by the formula M000 0 000M \C/ \C/ mooon: $90001 UNITED STATES PATENTS 2,264,103 11/1941 Tucker 252-89 3,308,067 3/1967 Diehl 252-89 3,580,852 5/1971 Yang 260347.3
WILLIAM E. SCHULZ, Primary Examiner US. Cl. X.R. 252-435