US 3684723 A
Description (OCR text may contain errors)
Aug. 15, 1972 P. BEST ETAL 3,684,723
DETERGENT COMPOSITION Original Filed May 14, 1968 4 Sheets-Sheet l Aug. 15, 1972 P. BEST ETAL 3,684,723
DETERGENT COMPOSITION Original Filed May 14, 1968 4 Sheets-Sheet 2 FIG. 3.
20 1.0 do an t FIG. 4.
2'0 in 60 do "c FIG.5.
20 1.0 s'n an 'r;
Aug. 15, 1972 P. BEST ETAL DETERGENT COMPOSITION 4 Sheets-Sheet 5 Original Filed May 14, 1968 Aug. 15, 1972 BEST ET AL 3,684,723
DETERGENT COMPOSITION Original Filed May 14, 1968 4 Sheets-Sheet &
2'0 1.0 5'0 an "r United States Patent 3,684,723 DETERGENT COMPOSITION Peter Best and Othmar Friedrich Schweigl, Vlaardingen, Netherlands, assignors to Lever Brothers Company, New York, N.Y.
Continuation-impart of abandoned application Ser. No. 729,120, May 14, 1968. This application Feb. 11, 1971, Ser. No. 114,728
Int. Cl. Clld 9/22 U.S. Cl. 252-132 3 Claims ABSTRACT OF THE DISCLOSURE A low-foaming detergent composition containing an anionic detergent, a builder salt and either a C fatty acid soap, a foam-depressant nonionic detergent or a mixture of the soap and the nonionic detergent is improved by the addition of 0.5 to 10% by weight of the composi tion of certain diethers of polyalkylene oxide diols that have a high-temperature foam depressant action. The composition can also contain a perborate bleach.
This application is a continuation of Ser. No. 729,120, filed May 14, 1968, now abandoned.
The invention relates to detergent compositions. More particularly the invention relates to built detergent compositions which are suitable for use in drum-type washing machines as well as in other types of washing machines.
In many types of washing machines, notably in automatic drum-type machines, a high lather volume should be avoided, since this not only adversely affects the washing performance owing to its cushioning effect, but it also causes overfoaming, particularly at higher temperatures. On the other hand, however, certain amount of foam is allowed and even desirable, especially in the low temperature range.
An ideal detergent composition for this purpose, therefore, would be one which is low-foaming to very low foaming at high temperatures, i.e. above about 80 C., and has acceptable foaming characteristics at temperatures of up to about 60 C. Such a detergent composition would be very suitable for use in drum-type washing machines and in any other type of washing machine, because in spite of its reasonable foaming capacity overfoaming at higher temperatures would be avoided. The present invention provides a process of preparing such detergent compositions.
Various attempts have been made to provide detergent compositions having reduced foaming characteristics in order to avoid the problem of overfoaming in drum-type washing machines. It is known, for example, that lather formation can be suppressed by the addition of general foam suppressors, such as liquid hydrocarbons or hydrocarbons which are solid at room temperature, such as paraflins or waxes. A drawback of these additives however, is that they reduce lathering bluntly, without regard to temperature.
Foam suppression has also been obtained by the use of so-called mixed-active detergent compositions. Such compositions usually contain about 5 to 30% by weight of anionic detergent, such as alkylbenzene snlphonate, alkyl sulphate, fatty alcohol sulphate and the like, as well as builder salt. The compositions are called mixed-active since they contain a minor proportion, about 1 to preferably 1 to 5% by weight of the composition, of soap, foam depressant nonionic detergent or a mixture of soap and the nonionic detergent. By soap is meant an alkali metal or ammonium salt of a C fatty acid. Suitable nonionic detergents include the alkylene oxide condensation products or alkyl alcohols, of alkyl phenols and of polyoxypropylene and of other organic hydrophobic compounds.
Detergent compositions of this type, the so-called mixed-active detergent compositions, can contain an oxygen-liberating bleaching agent, such as perborate, further silicate and small amounts of optical brighteners and soilsuspending agents, such as carboxymethylcellulose. The builder salt can be, for example, a salt of an organic acid such as nitrilotriacetic acid, ethane-l-hydroxy-1,1-diphosphonic acid or a polymeric carboxylic acid, or a salt of a polyphosphate such as sodium tripolyphosphate. The weight ratio of anionic detergent to builder salt is between 1:1 and 1:5. By weight of the composition the amount of perborate will be between 0 and 30% and of silicate between 0 and 15%.
Although the foam depressant action provided by the soap component in such detergent compositions is stronger according as the soap has a higher content of saturated molecules with at least 20 carbon atoms, such as soap from hardened marine oils or certain vegetable oils, it was established that these soaps still provide a distinct foam-- suppressing effect at low and medium temperatures, which in many respects is undesirable.
It has now surprisingly been found that controlling the foaming capacity of such mixed-active detergent compositions at different temperatures can be achieved better and more accurately than by conventional methods, by adding to the detergent composition a high-temperature foam suppressant of the general formula:
in which R and R are alkyl groups having a total number of 2 to 30 carbon atoms, R and R are each H or CH and n is variable over a wide range.
These compounds are thus diethers of polyalkylene oxide diols, the polyalkylene oxide groups of which are naturally not restricted to those consisting of equal alkylene oxides but may also be a mixed polymer of different alkylene oxides.
The invention provides a detergent composition containing an organic anionic detergent, as well as soap and/ or a nonionic detergent, characterised in that a compound is incorporated which is a diether of a polyalkylene oxide diol of the following general formula:
R;O CHOH-O R2 in which R and R are alkyl groups having a total number of 2 to 30 carbon atoms, R' and R" may each be H or CH and n is a number which is variable over a wide range.
It is remarkable that the monoethers of polyalkylene oxide diols, such as for example the monobntylethers of polybutylene glycol or of polypropylene glycol, do not give the desired effect, as is clearly shown by the graph in FIG. 8. With regard to the use of one representative from this group of monoether compounds in detergent compositions reference is made to U.S. patent specification No. 3,009,882.
The lather controlling effect of the diethers meant by the present invention increases with their molecular weight and reaches an optimum value. In general those compounds are very effective in which n is within the range from 2 to about 40, particularly, if the functional groups in the molecule are properly selected. A selection of the suitable functional groups within the specified ranges can be easily made by determining the Hydrophylic-Lipophylic Balance Value of the compound, which value should lie within the range of approximately 1.0 to approximately 4.0.
A suitable method for determining the HLB value of these compounds is the one developed by I. T. Davies, (I. T. Davies, Proceedings of the 2nd 'Int. Congress of Surface Activity, I. Butterworth Scientific Publications, London, 1957, p. 426). In this method use is made of the so-called group values, which makes it possible to calculate the HLB values of surface-active substances direct from the chemical formula.
Preferred compounds are those of which the polyalkylene oxide group is mainly or completely built up from propylene oxide groups. As such may be men tioned:
C H O--(PO) -C H --Butyl-polypropylene glycol ethyl ether/ 7 PO C H O(PO) -C H -Butyl-polypropylene glycol ethyl ether/ 12 PO C H (PO) --C H --Butyl-polypropylene glycol ethyl ether/ 18 PO C H O--(PO) C H -Hexyl-polypropylene glycol butyl ether/20 PO C H O-(PO) -C H -Butyl-polypropylene glycol ethyl ether/23 PO etc.
These compounds include those which are already conimercially available as a number of products under the UCON Lubricant trademark. They are usually prepared by reacting an aliphatic alcohol with alkylene oxide(s) in the presence of an alkaline catalyst, followed by etherification of the hydroxyl groups according to any of the various known methods, as described in US. patent specification No. 2,520,612.
Further compounds which may be mentioned within the scope of the invention are:
(PO) =propylene oxide (E0)=ethylene oxide (BO) =butylene oxide The ability of the aforesaid compounds to control the foaming capacity of detergent compositions at diiferent temperatures is so remarkable that small amounts of them already have the desired effect. The compounds concerned can be employed in the detergent compositions in an amount of about 0.5% to about by weight thereof; generally an amount of 0.5 to 5% is quite sufficient. In many cases it is suflicient according to the invention to use 1 to 3% of the compound in the composition in order to produce the desired foaming characteristics at low and medium temperatures, i.e. at temperatures up to about 60 0, whereas at elevated temperatures the foam suppressing eifect is practically complete. The detergent such as optical brighteners or other colorants, perborate stabilisers, bleach enhancers, perfumes, germicides, inorganic salts (0 to such as sodium sulphate, etc.
The use of the diether compounds according to the invention is not restricted to the washing of laundry, but they may also be advantageously applied in any other 4 cleaning process in which it is desired that at elevated temperature far less foam is produced in the low and medium temperature ranges.
The invention will now be illustrated by the following examples.
EXAMPLE 1 The effectiveness of the compounds as high-temperature foam suppressants is shown by the graph in FIG. 1, which was obtained by means of comparative tests made with the following detergent compositions in the dynamic foam meter at concentrations of 5 g./litre and using water having a hardness of 15 DH. In this and in the other graphs in the figures to be mentioned below the foam height of the relevant detergent compositions on the vertical axis is set against the temperature on the horizontal axis.
Parts by weight A prod- B produet uct Straight-chain alkybenzeno sulphouate 10 10 Soap from hardened tallow 2 2 Tallow fatty alcohol-25 E0 2 2 Sodium tripolyphosphate.. 30 30 Sodium pyrophosphate 8 8 Sodium orthophosphate 2 2 Sodium sulphate 10 10 Sodium metasilicate 10 10 Sodium perborate 20 20 Sodium carboxymethylcellulose 1 1 Butyl-polypropylene glycol ethyl ether/7 PO O 2 EXAMPLE 2 The foaming behaviour of the following detergent compositions was investigated in the dynamic foam meter under the same conditions as described before, viz:
Concentration g./litre 5 Water hardness DH 15 Parts by weight A prod- B prodnot not was determined in the same way as described in Example 1.
Parts by weight C D E prodprodprodnot not not Straight-chain alkylbenzene sulphonato 12 12 12 Soap from hardened tallow 2 2 2 Tallow fatty a1cohol25 E0 4 4 4 Sodium tripolyphosphate.. 3O 30 30 Sodium pyrophosphate. 8 8 8 Sodium orthophosphate 2 2 2 Sodium sulpha 10 10 10 Sodium metasilicate. 10 10 10 Sodium perborate 20 20 20 Sodium carb oxymethylcellulose 1 1 1 Butyl-polypropylene glycol ethyl ether/13 PO. 1 O 0 Butyl-polypropylene glycol ethyl ether/18 PO 0 1 0 Butyl-polypropylene glycol ethyl other/23 PO- 0 0 1 The results are shown by the graphs in FIG. 3 for the C product, in FIG. 4 for the D product and in FIG. 5 for the E product.
5 EXAMPLE 4 The foaming behaviour of the following detergent compositions was determined in the same way as described in Example 1.
Parts by weight F prod- G prodduct duct Dodecyl benzene sulphonate 12 12 Soap from hardened tallow 3 2 Sodium tripolyphosphate.. 30 30 Sodium pyrophosphate. 8 8 Sodium orthophosphate. 2 2 Sodium metasilicate 10 10 Sodium snlnhntn 5 5 Sodium perborate 20 20 Sodium carboxymethylcellulose 1 1 Butyl-polypropylene glycol ethyl ether/18 PO 1 The graphs in FIG. 6 show the result of these tests.
EXAMPLE The foaming behaviour of the following detergent compositions was determined in the same way as described in (Example 1. The results of these tests are shown by the graphs in FIG. 7.
All the above-mentioned examples distinctly show the foam controlling eifect of the addition of small amounts of the diether compound according to the invention, viz the slight to very slight foam-suppressing activity in the low to medium temperature ranges and the remarkable foam depression in the high temperature range.
For comparison the foaming behaviour is determined-- in the same way as described in Example lof a com position corresponding with that of Product C of Example 2, in which butyl-polypropylene glycol ethyl ether/ 13 PO has been replaced by the commercial product UCON Fluid DA 1905 (monobutylether of polypropylene glycol) known from US. patent specification No. 3,009,882. The results are shown by the graph in FIG. 8.
What is claimed is:
1. A built detergent composition with controlled foaming characteristics consisting, by weight, essentially of from 5 to 30% of an anionic non-soap synthetic detergent; from 1 to 10% of an alkali metal soap of fatty acids having from 8 to 25 carbon atoms; 0 to 10% of a nonionic synthetic detergent; 0 to 30% of sodium perborate; 0* to 15% of sodium silicate; and as a foam controlling agent about 0.5 to 10% of a compound of the general formula (l 1'. in which R and --R are alkyl groups having a total number of 2 to 30 carbon atoms, --R' is CH R" is a radical selected from the group consisting of H and CH and n is a number from 2 to 40, the Hydrophylic- Lipophylic Balance Value of the compound being from 1.0 to 4.0.
2. The detergent composition according to claim 1 in which R' is CH;, and R" is H.
3. The detergent composition according to claim 2, containing from 1 to 3% of the foam controlling agent.
References Cited UNITED STATES PATENTS 3,009,882 11/1961 Clarke et al. 252-121 X 3,281,475 10/ 1966 Boettner et al 252358 MAYER WEINBLATT, Primary Examiner US. Cl. X.R.