Low-foaming, liquid cleaning compositions containing paraffin and fatty acid salt

A liquid composition comprising a solubilized hydrophilic oil, a first surfactant which forms a calcium salt which is no more than sparingly soluble in an aqueous solution and a second surfactant which is foaming, different from the first surfactant and in weight excess over the first surfactant is described.

TECHNICAL FIELD 
The present invention relates to surfactant containing, liquid compositions 
which show a reduced tendency to form a stable foam. Such compositions are 
of particular utility in the cleaning of hard surfaces such as floors, 
walls, kitchen or bathroom surfaces and in cleaning soft furnishings such 
as upholstery, carpets, curtains etc. 
While other and broader use of such compositions is not excluded, such as 
use of the compositions in the manufacture of wood pulp and paper and 
generally in chemical processing, the compositions will be described with 
particular reference to hard surface cleaners. 
BACKGROUND 
The tendency to form a stable foam is a known problem with known hard 
surface cleaning compositions. While the formation of foam is desirable 
with many personal washing products, such as shampoos, bath additives and 
bar soaps, the presence of foam is often undesirable in fabric washing and 
surface cleaning operations. As a consequence, considerable effort has 
been directed toward the investigation of antifoaming systems for fabric 
washing powders (so-called `Automatic` powders) and in low-foaming carpet 
and hard surface cleaners. 
Antifoaming surfactant compositions are known which comprise mixtures of 
hydrophobic oils, such as silicone oils, together with particles, such as 
hydrophobic silica particles or occasionally alumina or titania particles. 
A large number of patents have been filed in this technical field. In 
practice antifoaming components are either added to the surfactant 
compositions during manufacture or shortly before use of said 
compositions. The step of adding the antifoam component just prior to use 
is more common with carpet cleaning compositions (which tend to be 
liquids) than with fabric washing powders. In washing powder technology it 
is virtually unknown in practice to mix components shortly before use. One 
reason for the late addition of the antifoam systems to liquid 
compositions is believed to be the tendency for insoluble particulate 
matter to settle out of solutions on storage. However, it has also been 
suggested, in GB 1407997 (P&G), that silicone antifoams are progressively 
deactivated if allowed to contact surfactants during processing and 
storage and complex encapsulation routes have been proposed to overcome 
these difficulties. 
The use of hydrocarbons and calcium sensitive, fatty acid soaps as antifoam 
systems for powder compositions has been disclosed in GB 1099562 
(Unilever: 1964). In that citation are disclosed powdered detergent 
compositions which comprise anionic sulphate or sulphonate detergents, 
alkaline polyphosphates and a `suds-depressant` mixture of a hydrocarbon 
and a fatty acid having from 12 to 31 carbon atoms. The hydrocarbon is 
broadly defined, as including straight or branched chain alkanes (liquid 
paraffin oils in 1:1 admixture with high melting paraffin waxes having a 
boiling point above 90.degree. C.), alkenes, alkylated benzene, condensed 
aromatics such as naphthalene and anthracene and their alkylated 
derivatives and alicyclic hydrocarbons, including terpenes and like 
compounds. Preferred hydrocarbons include those materials having a boiling 
point above 90.degree. C., such as the aforementioned mixtures of paraffin 
oils and waxes, dodecyl benzene and turpentine oil. 
The use of the combination of solvents, soaps and selected terpene solvents 
as antifoam systems for liquid hard surface cleaning compositions is 
further disclosed in EP 0080749 (P&G: 1982). In these compositions, unlike 
the carpet cleaning compositions mentioned above, it is particularly 
desirable that the product can be used at will without the step of adding 
a separate antifoam component. More specifically, EP 0080749 teaches the 
use of mono (two isoprene units) or sesqui- (three isoprene unit) terpenes 
in combination with both a specified solvent (2-(2-butoxy-ethoxy) ethanol: 
available in the marketplace as BUTYL CARBITOL [RTM]) and 0.05-2% wt of 
one or more of the alkali, ammonium and alkanol-ammonium soaps of C13-C24 
fatty acids as an antifoam system. In this citation, these three 
components are said to interact so as to have an antifoaming activity. The 
preferred terpenes as disclosed in this citation are the mono and 
bi-cyclic terpenes of the `hydrocarbon class` of terpenes such as 
terpinenes, terpinolenes, limonenes, pinenes and the so-called `orange` 
terpenes as obtained from the skins of oranges. Other terpenes including 
the terpene alcohols, aldehydes and ketones are less preferred. 
Terpenes and related compounds suffer from the general disadvantage that 
they are odiferous compounds and generally lend a pine-like or lemon-like 
odour to products. It is desirable that the base formulation of cleaning 
compositions should have a low odour or be odour free. Moreover, it is 
advantageous for some uses that compositions should also be free of 
solvents such as butyl carbitol. 
SUMMARY OF THE INVENTION 
According to the present invention there is provided a liquid composition 
comprising a solubilised hydrophobic oil and a first surfactant 
CHARACTERISED IN THAT: 
a) the hydrophobic oil is a saturated hydrocarbon with a 50% wt loss 
boiling point in the range 170.degree.-300.degree. C., 
b) the first surfactant forms a calcium salt which is no more than 
sparingly soluble in aqueous solutions of a second foaming surfactant, 
and, 
c) the composition comprises, in weight excess over the first surfactant, a 
second, foaming surfactant which is different from the first surfactant.

DETAILED DESCRIPTION OF THE INVENTION 
Without wishing to be bound by any theory of operation, it is believed that 
the concentrated compositions of the present invention comprise the 
hydrocarbon oil solubilised in micelies. As the composition is diluted 
with water of a hardness &gt;1 French at least a part of the saturated 
hydrocarbon is dissolubilised of solution along with at least a part of 
the calcium sensitive surfactant. 
It is further believed that the synergistic interaction of hydrophobic 
particles formed on dilution (i.e. the insoluble portion of the calcium 
salt of the first surfactant) and the hydrocarbon droplets lead to an 
effective foam control as regards the second surfactant. 
Accordingly, a further aspect of the present invention subsists in the use, 
as an antifoaming additive in a liquid cleaning composition comprising at 
least one foaming surfactant of a mixture of saturated hydrocarbon with a 
50% wt loss boiling point in the range 170.degree.-300.degree. C., and a 
surfactant other than the first above-mentioned surfactant which forms a 
calcium salt which is no more than sparingly soluble in aqueous solution. 
A particular advantage of such use of a hydrocarbon and a calcium sensitive 
surfactant, as an antifoam system for addition to or incorporation in a 
foaming cleaning composition, is that no particles are present in the 
initial system prior to dilution and consequently settling or other phase 
separation of these particles does not lead to the separation on storage 
difficulties mentioned above. 
Consequently, compositions according to the present invention are generally 
isotropic. An advantage of isotropic compositions, in which the 
hydrocarbon is initially solubilised, is that they need not be shaken or 
prepared by mixing shortly before use, whereas previous products either 
needed to be shaken before use, or, where suspensions of relatively large 
(silicone or fatty) oil droplets were employed, prior products required a 
high viscosity with the associated disadvantages of opacity and poor 
dosing/mixing properties. Isotropic compositions are also believed to have 
an improved temperature stability as compared with non-isotropic 
compositions. 
In the context of the present invention, a surfactant which forms an 
insoluble or sparingly soluble calcium salt in aqueous solution of foaming 
surfactants is generally one where the Krafft temperature of the calcium 
salt is above 45.degree. C. and the solubility product of the calcium salt 
is generally less than 10.sup.-8 Moles.sup.3 Liter.sup.-3. It is not 
intended that this limitation should be held to indicate that all 
surfactants with a solubility product in an aqueous solution of less than 
10.sup.-8 Moles.sup.3 Liter.sup.-3 are suitable, but only those 
surfactants which form a calcium salt which will still precipitate from a 
solution of foaming surfactant. It is believed that surfactants which form 
an insoluble or sparingly soluble calcium salt having a solubility product 
in a aqueous solution of foaming surfactant is greater than 10.sup.-8 
Moles.sup.3 Liter.sup.-3 would be unsuitable. 
Preferably, compositions according to the present invention are 
transparent. 
Hydrocarbon 
As mentioned above, the hydrophobic oil is a saturated hydrocarbon with a 
50% wt loss boiling point in the range 70.degree.-300.degree. C. 
In the context of the present invention the term 50% loss boiling point is 
intended to indicate that 50% of the weight of the paraffin can be 
distilled-off at a temperature within this range under a pressure of one 
atmosphere. 
Preferably the hydrocarbon is a paraffin. 
In general, the limits of boiling points of hydrocarbons, preferably 
paraffins, suitable for use in the composition of the present invention 
lie between 171.degree. and 250.degree. C. 
We have found that the isoparaffins, i.e. branched chain paraffins, are 
particularly effective. 
A further advantage associated with formulations based on the isoparaffins 
is that the compositions are essentially odour free. 
The hydrocarbon content of compositions embodying the present invention is 
typically in the range 0.2-10wt %, more preferably, 0.5-5% wt, most 
preferably 0.5-2.0wt %. 
Compositions according to the present invention can be free of terpenes and 
related aromatic compounds. 
First Surfactant 
As mentioned above, it is essential that the first surfactant forms a 
calcium salt which is no more than sparingly soluble in aqueous solutions 
of foaming surfactants. 
The insoluble or sparingly soluble calcium salt-forming surfactant content 
of embodiments of the invention is preferably 0.2-45% wt on product: the 
upper levels of this range being used for more highly concentrated 
compositions. 
Preferably the insoluble calcium salt-forming surfactant content is in the 
range 0.2-3.0% wt, most preferably in the range 0.6-2.0% wt. 
Surfactants which form insoluble or sparingly soluble calcium salts as 
hereinbefore defined include carboxylates and their salts, preferably 
fatty acids, soluble salts of fatty acids (traditional `soaps`) with a 
suitable cation, preferably derived from fatty acids having an average 
carbon chain length in the range 8-24. 
More preferably, the first surfactant is an alkali metal salt of saturated 
fatty acids having an average carbon chain length in the range 12-16. The 
sodium and potassium salts are most preferred. 
Alternative calcium-sensitive surfactants include calcium sensitive 
surfactant phosphates, sulphates and sulphonates. These share the common 
feature that they are anionic surfactants of which the calcium salt has a 
Krafft temperature above typical product use temperature. 
The use of carboxylates as the first surfactant, preferably fatty acids, 
and/or phosphates as the first surfactant is particularly preferred, with 
the fatty acid soaps being the most preferred first surfactant. 
The preferred ratio of insoluble calcium salt forming surfactant to the 
hydrocarbon is in the range 0.4-2:1. The most preferred ratios being in 
the range 0.9:1-1:0.9. 
Second Surfactant 
It is essential that the second surfactant, which can be a mixture of 
surfactant species is a foaming surfactant (or contains at least one 
foaming surfactant) and is different from the first surfactant. 
Typically, the second surfactant is selected from the group comprising, 
primary and secondary alcohol sulphate, alkyl aryl sulphonates, 
alkoxylated alcohols, primary and secondary alkane sulphonates, 
lactobionamides, alkyl polyglucosides, polyhydroxyamides, alkyl 
glucamides, alkoxylated carboxylates, mono- or di- alkyl sulphosuccinates, 
alkyl carboxylic acid ester sulphonates, alkyl isethionates and 
derivatives thereof and mixtures thereof. 
Preferably the second surfactant comprises one or more of the group 
comprising: primary alcohol sulphates, alkoxylated alcohols, alkane 
sulphonates and alkyl aryl sulphonates. More preferably the second 
surfactant comprises a mixture of primary alcohol sulphates and 
alkoxylated alcohols. More preferably the primary alcohol sulphates and 
alkoxylated alcohols are present in a ratio of from 3:1 to 1:1 with a 
ratio of around 2:1 being particularly preferred. 
The preferred primary alcohol sulphate (PAS) comprises a mixture of 
materials of the general formulation: 
EQU RO--SO.sub.3 X 
wherein R is a C.sub.8 to C.sub.18 primary alkyl group and X is a 
solubilising cation. Suitable cations include sodium, magnesium, 
potassium, ammonium and mixtures thereof. 
Particularly preferred PAS molecules are those with a major proportion of 
C.sub.10 -C.sub.14 alkyl residues. 
These surfactants can be obtained by forming the primary alcohol sulphate 
from fatty acids obtained from renewable resources such as coconut oil 
although they can also be obtained from synthetic alcohol sources. These 
surfactants show very acceptable biodegradation behaviour. 
The preferred alkoxyalated alcohols are selected from the group comprising 
ethoxylated alcohols of the general formula: 
EQU R.sub.1 --(OCH.sub.2 CH.sub.2).sub.m --OH 
wherein R.sub.1 is straight or branched, C.sub.8 to C.sub.18 alkyl and the 
average degree of ethoxylation m is 1-14, preferably 3-8. 
The starting materials for the synthesis of these ethoxylated alcohols are 
available from both natural and synthetic sources. 
Solvents 
Compositions according to the present invention can further comprise a 
solvent, preferably, when present, at level of 5-15% wt on product. 
It is believed that the presence of the solvent assists in the 
solubilisation of the hydrocarbon into micelies. However, as will be shown 
hereinafter by way of example, the presence of solvents is not a necessary 
feature of the compositions according to the present invention. 
Preferably, any solvent present is selected from: propylene glycol mono 
n-butyl ether, dipropylene glycol mono n-butyl ether, propylene glycol 
mono t-butyl ether, dipropylene glycol mono t-butyl ether, diethylene 
glycol hexyl ether, ethyl acetate, methanol, ethanol, isopropyl alcohol, 
ethylene glycol monobutyl ether, di-ethylene glycol monobutyl ether and 
mixtures thereof. 
Most, preferably the solvent is a glycol ether or C.sub.2 -C.sub.5 alcohol 
solvent. 
Particularly preferred solvents are selected from the group comprising 
ethanol (preferably as industrial methylated spirits), propylene glycol 
mono n-butyl ether (available as `Dowanol PnB` [RTM]) and di-ethylene 
glycol monobutyl ether (available in the marketplace both as `Butyl Digol` 
[RTM] or `Butyl Carbitol` [RTM]). 
Minors 
The compositions of the invention can further comprise other components 
selected from the group comprising: perfumes, colours and dyes, hygiene 
agents, viscosity modifying agents, antioxidants, buffers and mixtures 
thereof. These minor components are not essential for the performance of 
the invention but the presence of one or more of these components is 
preferred in practical embodiments of the invention. 
It is preferable, where primary alcohol sulphate is present as surfactant 
that compositions according to the invention comprise a potassium salt as 
a minor ingredient. It is believed that the presence of such salts 
improves the low temperature stability of the products. 
Particularly preferred compositions according to the present invention 
comprise: 
a) 15-30% wt primary alcohol sulphate (i) and 5-15% nonionic surfactant 
(ii) wherein the ratio of (i):(ii) falls in the range 3:1 to 1:1, 
b) 1-5% wt potassium carbonate, 
c) 5-15% wt glycol ether or C.sub.2 -C.sub.5 alcohol solvent, 
d) 0.2-5% wt of a paraffin with a 50% wt loss boiling point in the range 
170-300 Celsius, and, 
e) 0.2-5% wt of a salt of saturated fatty acids having an average carbon 
chain length in the range 12-16. 
EXAMPLES 
In order that the present invention may be further understood it will be 
illustrated hereafter by way of non-limiting examples. 
EXAMPLES 1-14 
In the following examples the effectiveness of an antifoaming composition 
was evaluated against comparative examples both by a `cylinder shaking` 
test method and a `bowl-filling` test method. 
In the `cylinder-shaking` test method, 1.5 ml of product was introduced 
into 50 mls of water in a 100 ml stoppered measuring cylinder and shaken 
vigorously 40 times by hand. In order to maintain the vigour of the 
action, the hand was changed after 20 shakes. Each shake involved a 
vertical up/down motion of 30 cm and, on average, twenty shakes occurred 
every 5 seconds. After shaking the stoppers were removed and the initial 
foam height was measured. The maximum foam volume could be calculated from 
this. The `decay time`, i.e. the time taken for the foam to collapse to a 
level at which less than 5 ml remained was also determined and recorded. 
The source of water used was varied and is noted below. 
The `bowl-filling` test method approximates the process of filling a bucket 
for floor cleaning. 5 liters of water was fed into a 10 liter bowl 
containing 30 mls of product from a 60.degree. semi-angle funnel through a 
20 cm by 13 mm diameter pipe with its end 30 cm above the floor of the 
bowl. Local well water (12-15 French) was used. Foam collapse as 
`half-life` was measured by the time taken for the foam volume to fall 
such that 50% by area of the air water interface was clear of foam. 
The bowl filling test is considered to be a more accurate test of the 
performance of the products in actual use than the cylinder shaking test. 
As a comparative example, paired comparison examples were repeated with a 
control formulation and a commercially available floor cleaning 
composition (AJAX CITRON VERT) [RTM], which is believed to employ a 
terpene-perfume/soap based antifoam system stabilised as a microemulsion 
in the concentrated (neat) product. In addition comparative examples were 
performed with terpenes and similar perfume components replacing the 
hydrocarbon. 
The BASE formulation as used in the following examples employed linear 
alkylbenzene sulphonate (sodium salt of DOBS [RTM] 102) and alcohol 
ethoxylate (IMBENTIN [RTM] 91-35 OFA) as a surfactant system. The base 
formulation was as follows: 
TABLE 1 
______________________________________ 
C10-Cl2 LABS 4.6% wt 
C9-C11 Alcohol 5EO 3.5% wt 
Butyl Digol 5.0% wt 
Sodium Carbonate 0.5% wt 
Perfume 0.6% wt 
Formaldehyde 0.03% wt 
Distilled water to 100% 
______________________________________ 
It will be noted that the BASE composition is free of both hydrophobic 
hydrocarbon oil and the calcium sensitive surfactant. 
For the CONTROL used in the experiments, 0.4% Coconut Soap (Sodium Salt) 
was added to the BASE formulation. Coconut soap is a calcium sensitive 
surfactant. 
In the SOLVENT BASE formulation mentioned below the formulation of the 
composition was as given above for the BASE, except that 1.0% ISO-L 
(RTM, ex Exxon), commercially available, odour free, branched hydrocarbon 
with a boiling point range of 171.degree.-191.degree. C. was added to the 
BASE formulation. This was solubilised by the surfactant present to form a 
clear solution. 
Various levels of Coconut soap were added to the SOLVENT BASE as detailed 
in the tables below, in order that the synergistic effects of the calcium 
sensitive soap and the hydrophobic oil could be demonstrated. 
The formulation of EXAMPLE 2 comprised 0.5% ISO-L added to the CONTROL 
formulation (i.e. 0.5% oil plus 0.4% soap). 
In EXAMPLE 3 mentioned below, the formulation of the composition was as 
given above for the CONTROL, except that 1% ISO-M (RTM, ex Exxon), a 
branched hydrocarbon with a boiling point range of 207.degree.-256.degree. 
C. was added to the CONTROL formulation (i.e. 1% oil plus 0.4% wt soap). 
In EXAMPLE 4, 0.25% ISO-M was added to the CONTROL formulation (i.e. 
0.25% oil plus 0.4% soap). 
In EXAMPLE 5, 1.0% n-decane (boiling point 174.degree. C.) was added to the 
CONTROL formulation (i.e. 1.0% oil plus 0.4% soap). 
In EXAMPLE 6, 1.0% n-tetradecane (boiling point 254.degree. C.) was added 
to the CONTROL formulation (i.e. 1.0% oil plus 0.4% soap). 
In EXAMPLE 7, 1.0% of ISO-G (RTM ex. Exxon), a branched hydrocarbon with 
a boiling point range of 155.degree.-175.degree. C. was employed. 
In EXAMPLES 8-14, 1.0% of one of the following odiferous essential oils and 
similar compounds, each commonly used as a perfume or perfume ingredient 
in cleaning compositions was substituted for the hydrocarbon: 
TABLE 2 
______________________________________ 
EXAMPLE INGREDIENT TYPE 
______________________________________ 
8 Limonene Monoterpene 
9 Linalool Terpenoid 
10 Citronellal Terpenoid 
11 Cyclohexanol Cycloalkanol 
12 Benzyl alcohol Aromatic alcohol 
13 Menthol Terpenoid 
14 Glycerol triacetate 
Triglyceride 
______________________________________ 
The following averaged or ranged results were obtained with the controls 
and formulations given below in repeated experiments taking the average of 
4-5 duplicates in each instance: 
TABLE 3 
______________________________________ 
CYLINDER-SHAKING 
MAX. 
VOLUME DECAY TIME 
______________________________________ 
25 French Water at 21.degree. C. 
CONTROL (soap, no solvent) 
45 3 min 33 sec 
`AJAX` 24 0 min 31 sec 
SOLVENT BASE + 0.4% SOAP 
32 0 min 21 sec 
Demineralised water 
CONTROL (soap, no solvent) 
-- &gt;20 min 
(stable) 
`AJAX` -- &gt;20 min 
(stable) 
SOLVENT BASE + 0.4% SOAP 
-- 3-4 min 
______________________________________ 
From the results given in Table 3 it can be seen that the embodiments of 
the present invention show an improvement over controls with hard water 
and a very significant improvement with `very soft` water. 
In particular, the hydrocarbon-based systems of the present invention show 
a significant improvement over the terpene-based systems of the prior art 
under the worst possible, (i.e. using de-ionised water) circumstances. 
TABLE 4 
______________________________________ 
BOWL FILLING 
Foam `half-life` 
______________________________________ 
BASE (no HC, no soap) &gt;300 sec 
CONTROL (soap, no HC) &gt;300 sec 
`AJAX` (terpene, soap) 102-201 sec 
SOLVENT BASE (HC, no soap) 
&gt;300 sec 
SOLVENT BASE + 0.1% soap 
&gt;300 sec 
SOLVENT BASE + 0.2% soap 
&gt;300 sec 
SOLVENT BASE + 0.4% soap 
32-108 sec 
SOLVENT BASE + 0.6% soap 
19-34 sec 
SOLVENT BASE + 0.8% soap 
27-37 sec 
SOLVENT BASE + 1.0% soap 
51-55 sec 
EXAMPLE 2 (half solvent level) 
c. 60 sec 
EXAMPLE 3 (Isopar M) 26-34 sec 
EXAMPLE 4 (Isopar M) 120-180 sec 
EXAMPLE 5 (n-decane) 60-120 sec 
EXAMPLE 6 (n-tetradecane) 
60-120 sec 
EXAMPLE 7 (isododecane) 
&gt;300 sec 
EXAMPLE 8 (Limonene) &gt;200 sec 
EXAMPLE 9 (Linalool) &gt;200 sec 
EXAMPLE 10 (Citronellal) 
&gt;200 sec 
EXAMPLE 11 (Cyclohexanol) 
&gt;200 sec 
EXAMPLE 12 (Benzyl alcohol) 
&gt;200 sec 
EXAMPLE 13 (Menthol) &gt;200 sec 
EXAMPLE 14 (Glycerol Triacetate) 
&gt;200 sec 
______________________________________ 
From the results given in Table 4 can be seen that under these harsher test 
conditions that significant effects were obtained with additions of 
upwards of 0.4% soap to the control formulation. In the presence of 
neither solvent or soap, in the presence of solvent without soap or in the 
presence of soap without solvent, foam control was inadequate. 
In the presence of around 0.5-1.0% wt soap, with 1 wt % hydrocarbon in 
formulations according to the present invention, product performance in 
12-15 French water was comparable with the commercial product based on 
terpenes. From Table 4 it can also be seen that where other hydrocarbons 
were used (see comparative EXAMPLE 7) or terpene or related compounds were 
used (comparative EXAMPLES 8-14) product performance was poor as compared 
with embodiments of the present invention (EXAMPLE 2-6 and examples with 
SOLVENT BASE plus 0.4-1.0% wt soap). Limonene, while showing acceptable 
behaviour in cylinder-shaking tests, showed poor behaviour in the bowl 
filling test (EXAMPLE 8). 
EXAMPLE 15 
The following formulation was prepared by mixing of the components as 
listed in Table 5. The components are identified as follows: 
Sodium PAS: LIAL-123S (RTM ex. Enichem), a sodium salt of primary alcohol 
sulphate having an average alkyl chain length in the range C.sub.12 
-C.sub.13 ; 
Nonionic: BIODAC L5-S52 (RTM: ex DAC), alcohol ethoxylate; 
Solvent: Butyl Carbitol (RTM: ex Union Carbide); 
TABLE 5 
______________________________________ 
COMPONENT EXAMPLE 
______________________________________ 
Sodium PAS 18.5% wt 
Nonionic 9.5% wt 
Coconut fatty acid 1.4% wt 
Solvent 8.0% wt 
Perfume 1.5% wt 
Isoparaffin 1.5% wt 
Potassium Carbonate 3.0% wt 
Sodium Hydroxide to pH 11 
Distilled water to 100% wt 
______________________________________ 
The product showed excellent cleaning performance and low foaming. In 
addition when the formulation of EXAMPLE 15 was cooled to 0.degree. C. and 
stored for 24 hours at that temperature, before re-heating to room 
temperature, the composition formed a semi-liquid slurry when cold, but 
when re-heated to room temperature the slurry became liquid without any 
phase separation. Even after multiple freeze/thaw cycles or prolonged 
storage at -15.degree. C. there was no irreversible phase separation. 
EXAMPLES 16-23 
The formulations of Examples 16-23, as given in Table 6, illustrate the 
behaviour of the antifoaming compositions according to the present 
invention in the absence of the solvents/hydrotroping agents mentioned in 
EP 0080749. Components are identified as follows: 
SAS: SAS-30 [RTM]; secondary alkyl sulphonate, anionic surfactant ex. 
Hoechst. 
AEO: IMBENTIN 91-35 [RTM]; alcohol ethoxylate, nonionic surfactant. 
Soap: Coconut soap, sodium salt of coco fatty acids. 
Compositions were prepared by simple mixing of the components. All were 
clear, isotropic liquids. 
Results are given for foam collapse time in a bowl filling experiment as 
described above. 
TABLE 6 
______________________________________ 
COM- 
PO- EXAMPLE 
NENT 16 17 18 19 20 21 22 23 
______________________________________ 
SAS 4 4 4 4 -- -- -- -- 
AEO 8 8 8 8 16 16 16 16 
Soap 1 1 -- -- 1.2 -- 1.2 -- 
Isopar-L 
1 -- 1 -- 2 2 -- -- 
Collapse 
20 150 &gt;300 &gt;300 5 &gt;300 120 &gt;300 
time 
(sec) 
______________________________________ 
Examples 16-19 employ a SAS/Alcohol ethoxylate surfactant system whereas 
examples 20-21 employ a main surfactant system consisting solely of 
alcohol ethoxylate. 
From Table 6 it can be seen that compositions which comprise both the 
paraffin hydrocarbon and the fatty acid soap (Examples 16 and 20) show a 
very acceptable foam collapse time in the absence of the solvent 
component, whereas the omission of either the hydrocarbon (Examples 17 and 
22) or the soap (Examples 18 and 21), or both soap and hydrocarbon 
(Examples 19 and 23) resulted in an unacceptably long foam collapse time. 
All percentages are by weight.