US3689418A - Detergent formulations - Google Patents

Abstract

DETERGENT FORMULATIONS COMPRISING TETRA ALKALI METAL ETHENE TETRACARBOXYLATE AS A DETERGENCY BUILDER IN COMBINATION WITH CONVENTIONAL SURFACTANTS PROVIDE EFFECTIVE CLEANING ACTION.

Description

United States Patent 3,689,418 DETERGENT FORMULATIONS Russell D. Harken, St. Louis, Mo., assignor to Monsanto Company, St. Louis, M0. N0 Drawing. Filed Jan. 18, 1971, Ser. No. 107,468

Int. Cl. Clld 1/12 US. Cl. 252-89 '3 Claims ABSTRACT OF THE DISCLOSURE BACKGROUND OF THE INVENTION This invention relates to novel detergent formulations characterized by the use therein of tetra alkali metal ethene-1,l,2,2-tetracarboxylate as a detergency builder in combination with conventional surfactants.

The basic and essential ingredient of any detergent formulation is a surfactant which by reason of its surface active characteristics in solution, wetting properties, foaming properties, emulsifying action and/or other properties is effective in removal of soil or dirt.

Detergent formulations commonly contain at least one other ingredient serving as a adjuvant, re-enforcer, supplement, augmentor, potentiator and/or beneficator which serves to improve or enhance the cleansing ability of the formulation in various applications. Such other ingredients are usually referred to as detergency builders.

In addition to providing adequate functional charac-' teristics, it is desirable that the ingredients of detergent formulations be free of adverse ecological effects, at least in those instances where the ingredients will be released into the environment. For example, it is desirable that organic ingredients of detergent formulations be capable of bio-degradation in conventional sewage processing operations. Further, it has been suggested that the quantities of phosphorus contained in detergency builders may contribute to eutrophication processes. Accordingly, it may be ecologically desirable to provide detergency builders of reduced phosphorus content.

SUMMARY OF THE INVENTION It is object of this invention to provide novel detergent formulations.

These formulations comprise a surfactant and tetra alkali metal ethene 1,1,2,2 tetracarboxylate. The tetra alkali metal ethene-l,1,2,2-tetracarboxylate in addition to providing detergency builder function is free from phosphorus and substantially totally bio-degradable in activated sludge treatment such as utilized in many sewage processing operations.

The invention will be better understood from the following description of the preferred embodiments.

DESCRIPTION OF THE PREFERRED EMBODIMENTS The detergent formulations of this invention will contain from 1% to 60% by weight, preferably from 5% to 40% by weight, of tetra alkali metal ethene-1,l,2,2-tetracarboxylate. The tetra sodium salt is generally preferred.

The tetra alkali metal ethene-1,l,2,2-tetracarboxylate can be prepared by treating diethyl bromomalonate with sodium carbonate followed by basic hydrolysis of the tetraethyl ester according to procedures such as described by Malachowski and Sienkiewiczowa, Ber., 68, 33 (1935) and in Organic Synthesis, coll. vol. II, p. 273 (1943).

Patented Sept. 5, 1972 The tetra alkali metal ethene-l,1,2,2-tetracarboxylate can be utilized as the sole detergency builder in the compositions of this invention or in combination with other known detergency builders such as water-soluble, inorganic builder salts, for example, alkali metal carbonates, borates, phosphates, polyphosphates, bicarbonates and silicates or organic builders, for example, alkali metal, ammonium or substituted ammonium, aminopolycarboxylates, salts of pyhtic acid, sodium citrate, water-soluble polymeric polycarboxylates as described in US. Pat. 3,308,067 and the like. Examples of such other known builders which have been extensively utilized commercially include sodium tripolyphosphate and sodium nitrilotriacetate.

The detergent formulations of this invention 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 ethyl sulfonates, alkyl sulfates, acyl sarcosinates; acyl esters of isethionates, 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 such as described in US. patent application Ser. No. 707,480 filed Feb. 23, 1968 and copending herewith; condensates of monohydroxy or polyhydroxy alcohols such as oleyl alcohol or 1 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. 852,898 filed Aug. 25, 1969 and copending herewith; and condensates of alkylene oxides with organo amines, for example, ethylene diamine and amides such as N-octadecyl diethanol amide.

Examples of cationic surfactants include octadecyl ammonium chloride; straight chain fatty amines having 8 to 18 carbon atoms; and quaternary ammonium compounds such as octadecyl trimethyl ammonium chloride.

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 water-solubilizing substituent such as a carboxy, sulfo, phosphato, or phosphino group, for example, sodium-3-dodecyl amino propionate and sodium-3-dodecyl amino propane sulfonate,

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 supplementary surfactants are by no means comprehensive. Numerous other surfactants are known to those skilled in the art are set forth in such familiar references as Surface Active Agents by A. M. Schwarz and James W. Perry. It will be further understood that the use of such surfactants will be in accordance with conventional, wellunderstood practices of detergent formulation. For example, cationic and anionic detergents will not normally be employed in combination due to recognized problems of precipitation of insoluble products.

Since the alkali metal ethene tetracarboxylate builder is substantially totally bio-degradable, preferably the surfactant chosen will be similarly bio-degradable.

In accordance with general practice, the ratio of the deter'gency builder 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 of this invention 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 ex ample wherein all parts and percentages are by weight unless otherwise indicated.

EXAMPLE Detergent formulations are prepared containing about 17 parts linear sodium alkylbenzene sulfonate having an average molecular weight of about 230; 8.5 parts silicate having a 1:2 ratio of Na O:SiO 24.5 parts sodium sulfate and 50 parts tetra sodium ethene-1,1,2,2-tetracarboxylate. This composition is compared in cleaning effectiveness on polyester/cotton and cotton fabrics with an otherwise identical composition containing no tetra sodium ethene- 1,1,2,2-tetracarboxylate. Detergency performance of the formulations containing the builder as determined by measurement of the difference in reflectance of washed and unwashed samples averages more than 30% better 30 tained with formulations containing 25 parts and 38 parts tetra sodium ethene-l,1,2,2-tetracarboxylate. I

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, and ampholytic surfactants and from 1% to 60% by weight tetra alkali metal ethene-l,1,2,2-tetracarboxylate.

2. The composition of claim 1 wherein said tetra alkali metal ethene-1,l,2,2-tetracarboxylate is tetra sodium ethene-l,1,2,2-tetracarboxylate.

3. The composition of claim 2 wherein said tetra sodium ethene-1,1,2,2-tetracarboxylate is present in an amount of from 5% to 40% by weight.

References Cited UNITED STATES PATENTS 2,264,103 11/ 1941 Tucker 21023 2,311,008 2/1943 Tucker 21023 3,459,670 8/ 1969 Carter 252-99 3,580,582 5/1971 Yang 252-135 OTHER REFERENCES Chem. Absts., vol. 52, p. 16192.

LEON D. ROSDOL, Primary Examiner P. E. WILLIS, Assistant Examiner US. Cl. X.R.