Note: Descriptions are shown in the official language in which they were submitted.
~, 2173137
O9~/27034 PCT~5/~90
DETERGENT COMPO5ITIONS
T~CHNIC~T, FT~r,n
The present invention relates to ~ ergent comp~sitions
containing a surfactant and a solvent in the form of an oil-
in-water microemulsion.
R~CKGROUND AND PRIOR A~T
Li~uid detergent and cleaning compositions in the form
of microemulsions, both oil-in-water and water-in-oi~, have
been disclosed in the prior art.
EP 137 616A (Procter & Gamble) discloses liquid
detergent compositions prepared from conventional detersive
surfactants and other conventional detergent ingredie~ts,
plus a grease-cutting solvent. The compositions contain
fatty acids or soaps (5-50 wt%) as detergency builders and
are formulated as stable oil-in-water microemulsions. The
preferred surfactant systems comprise sulphonate or s~lphate
type anionic surfactants with minor amounts of ethoxylated
nonionic surfactants such as Cl4l5 alcohol ethoxylate~ ~7EO).
Detergency builders may be present in amounts of 0.5-1~ wt%,
citrates being preferred.
EP 164 467A (Procter ~ Gamble) discloses laundry
detergents and hard surface cleaners comprising oil-~n-water
microemulsions, containing alkylbenzene and olefin so~vents,
plus surfactants and substantial amounts of fatty acid soap.
The compositions may contain ethoxylated nonionic
surfactants, for example, Cl4l5 alcohol ethoxylate (7E~.
Compositions containing sodium citrate as builder are
disclosed. ~ -
C3580PCl 2 ~ 73 ~ 3 7
- 2 -
In "Evaluation of Textile Detergent Efficiency of
Microemulsions in Systems of Water, Nonionic Surfactant and
Hydrocarbon at Low Temperature", J Dispersf on Science and
Technology, 6(5), 523-537 (1985), Marcel Dekker Inc, C
Solans, J Garcia Dominguez and S E Friberg describe the use
of such microemulsions for washing under conditions of
minimum mechanical energy and at low temperatures. The
systems studied contain CL7 alkyl ethoxylate (4EO) nonionic
surfactant, water and hexadecane, and optionally small
amounts of cosurfactant (sodium dodecyl sulphate), or
electrolyte (sodium tripolyphosphate or sodium citrate).
GB 2 194 547A (Colgate-Palmolive) discloses a clear
single-phase liquid pre-spotting composition in the form of
a microemulsion (oil-in-water or water-in-oil), solution or
gel, comprising 10-70 wt% alkane (solvent), 4-60 wt%
nonionic surfactant, optional cosurfactants and/or
cosolvents, and 1-80 wt% water. It is suggested that
builders such as sodium sesquicarbonate might be included,
preferably at levels of 5 wt% and above. Unbuilt water-
in-oil microemulsions are specifically disclosed which
contain the short-chain nonionic surfactant Neodol 91-6
alone or in conjunction with a longer-chain (Cl4ls)
ethoxylated nonionic surfactant.
CA 2 013 431A (Pennzoil Products Company) discloses
unbuilt microemulsion cleaners for engine cleaning and
degreasing, containing solvents and nonionic surfactants.
GB 2 259 518A (Shell) discloses unbuilt microemulsion
cleaning compositions for use in seawater, containing
anionic and nonionic surfactants, aromatic hydrocarbon and
water.
A.~ L~S~EET
C3580PC1 2 ~ 73 ~ 3 7
DEFINITION OF THE IMVEMTIOM
The present invention provides a fabric washing
detergent composition comprising an organic surfactant
system and a non-aqueous solvent which together with water
form a stable oil-in-water microemulsion, the composition
comprising:
(i) from 2 to 40 wt% of an organic surfactant system
comprising:
(a) 50-100 wt% of ethoxylated alcohol nonionic
surfactant having an average alkyl chain length of
less than Cl~ and a content of Cl~ material (based on
the alcohol) of at least 45 wt%;
(b) optionally up to 50 wt% of co-surfactant other
than ethoxylated alcohol nonionic surfactant,
(ii) from 0.5 to 55 wt% of non-aqueous solvent,
(lii) from 0.1 to 5 wt% of water-saluble detergency
builder selected from sodium tripolyphosphate and
polymeric detergency builders,
(iv) water and optional minor ingredients to 100 wt%,
DETAILED DESCRIPTIOM OF THE INVENTIOM0
The present inventors have now discovered that built
detergent compositions in oil-in-water microemulsion form,
formulated with specific nonionic surfactants having short
alkyl chains and specific builders, are capable of
sufficiently rapid cleaning and stain removal to render
them useful as pretreatment products as well as main wash
products.
A~E~3~ ~SHEET
2173137
os~/27034 PCT~95/oo~o
Rapidity of cleaning effect is of critical importance
for a pretreatment product which is required to work w~thin
a short time period. The present invention enables
detergent compositions to be formulated which are highly
effective main wash products and yet wh;ch also offer a
potent pretreatment facility.
The compositions are also suitable for use in machine
washing employing automatic dosing systems, for example, as
described and claimed in US 4 489 455 (Procter ~ Gam~
This patent describes and claims apparatus and process for
washing textiles based on utilising strictly limited o~
controlled ~uantities of an aqueous wash liquor, ransi~g
from (at least) just enough to be distributed evenly a~
completely over the whole wash load, to (at most) about five
times the dry weight of the washload.
In the compositions of the invention, which are
preferably liquid, the ethoxylated nonionic surfactant and
the solvent are so chosen, and are present in amounts such
that, together with water, they form a stable oil-in-water
microemulsion in which the solvent is within the micelles of
the surfactant.
The ethoxvlated nonionic surfactant
The ethoxylated nonionic surfactant has an average
alkyl chain length which is less than 12 carbon atom~
Preferably the average alkyl chain length is within the
range of from 9 to 11 carbon atoms, and most preferably the
average alkyl chain length is about C10.
The ethoxylated nonionic surfactant is also
characterised by a high content of C10 material: at least
45 wt%, preferably at least 50 wt% and most preferably at
least 70 wt% (all based on the alcohol).
.~
2~73137
~NO 9~/27034 PCT/EP95/00~0
The remainder of the ethoxylated nonionic surfactant
may be of predominantly shorter or longer chain length, but
advantageously the total content of C10 and shorter-chain
material is at least 60 wt%, and more preferably at least
75 wt~ (all based OIl 'he alcohol).
Suitable materials are the Novel (Trade Mark) 1012
series ex Vista, which are narrow-range-ethoxylated
materials consisting mainly of C1O ch~- ns, available in
various average degrees of ethoxylation. The chain length
distribution of these materials ~based on the alcohol) is
typically C1O 84 + 4%, Cl2 8.5 + 2~, Cl4 6.5 + 2%.
A class of broader-range-ethoxylated materials suitable
for use in the invention is the Dobanol (Trade Mark) 91
series ex Shell, which consist mainly of C9, C1O and Cll
chains. The chain length distribution of these materials
(based on the alcohol) is typically Cg 18%, C1O 50%, Cll 32%.
Other short chain nonionic surfactants are described in
detail in WO 94 11~87A (Unilever). These include the
Lialet (Trade Mark) 91 series ex Enichem, the Synperonic
(Trade Mark) 91 series ex ICI, and a C1O Inbentin (Trade
Mark) material ex Kolb.
Commercial ethoxylated nonionic surfactants are
generally mixtures containing a spread of chain lengths
about an average value. If desired, a mixture of two or
more commercial materials may be used provided that the
overall average chain length of all nonionic surfactant
present is less than Cl2 and provided that sufficient C10
material is present in the overall mixture.
The average degree of ethoxylation may suitably range
from 2 to 8, and preferably from 2 to 6, in order to give
optimum HLB (hydrophilic-lipophilic balance) values
corresponding to optimum oily soil detergency.
2173137
woss/27034 6 PcT~Pss/oosso
The HLB value sultably ranges from 8 to 14, preferably
from 8 to 12.5, and more preferably from 9 to 10.
l~e o~tional cosurf~ct~nt
If desired, a cosurfactant which is not an ethoxylated
alcohol may be present, provided that at least 50 wt% of the
surfactant system is constituted by ethoxylated nonionic
surfactant. The co-surfactant may be, for example, a
nonionic surfactant other than an ethoxylated alcohol, or an
anionic sulphate or sulphonate type detergent, such as
alkylbenzene sulphonate or primary alcohol sulphate. It is
generally preferred that the surfactant system should
contain not more than 40 wt% of anionic surfactant.
The surfactant system as a whole constitutes from 2 to
40 wt% of the composition, preferably from 5 to 40 wt%, more
preferably from 5 to 30 wt% and advantageously from 5 to
25 wt%, of the composition.
The non-~aueous solvent
The non~aaueous solvent, which constitutes from 0.5 to
55 wt%, preferably from 0.5 to 20 wt%, of the composition,
may be any solvent valuable in the removal of oily soil
which exhibits a sufficiently low interfacial tension
towards the ethoxylated nonionic surfactant to form a stable
oil-in-water microemulsion.
The solvent may range from wholly non-polar paraffinic
materials, for example, alkanes, to more polar materials
such as esters. Preferred solvents are Cl2l6 alkanes, for
example, dodecane, tetradecane and hexadecane, hexadecane
being especially preferred.
~ C3580PCl 2~ 73137
When the solvent is an alkane, the optimum amount
present depends on the chain length. For hexadecane, from
0.5 to 20 wt%, preferably from 5 to 15 wt% and more
preferably from 7.5 to 15 wt%, is suitable; for
tetradecane, 15 to 30 wt% is preferred, and for dodecane,
25 to 55 wt% is preferred.
The weight ratio of non-aqueous solvent (alkane) to
ethoxylated nonionic surfactant is also dependent on chain
length. For hexadecane, it lies suitably within the range
of from 0.5:1 to 2:1, and is advantageously about 1:1.
The deteraencY builder
It has been found that the detergency of the
microemulsion system, as compared to the detergency of the
same amount of surfactant alone, is significantly increased
if there is also present a detergency builder selected from
sodium tripolyphosphate and polymeric detergency builders.
` The amount of builder that can be incorporated without
destabilising the microemulsion is not, however, unlimited.
Suitably, the builder may be present in an amount of from
0.1 to 5 wt~, preferably from 0.2 to 3 wt~, more preferably
from 0.5 to 3 wt%.
Preferred polymeric builders for use in the present
invention are polymeric polycarboxylate builders, for
example, acrylic, maleic and itaconic acid polymers.
AME~ S~EET
~ C358GPC1 2 ~ 7~ 1 37
-- 8 --
Polymers that may be used include polyacrylates,
acrylic/maleic copolymers such as Sokalan (Trade Mark) CP5
and CP7 ex BASF, and the polyvinyl acetate/polyitaconic
acid polymers described and claimed in WO 93 23444A
(Unllever). These polymers are highly weight-effective
builders which can be used in amounts that give significant
building without destabilising the microemulsion.
The invention is further illustrated by the following
non-limiting Examples, in which parts and percentages are
by weight unless otherwise stated.
~XAMPLES
Deteraencv assessment
Oily soil detergencies were assessed by measuring the
percentage removal of radio-labelled model soils by means
of a scintillation counter.
Soiled cloths (5 cm x 5 cm squares of knitted
polyester) carrying a mixture of radiolabelled triolein and
radiolabelled palmitic acid were prepared as follows.
Each cloth was soaked in 0.18 ml of a toluene solution
containing 3.33 g 95% triolein (radiolabelled) and 1.67 g
99~ palmitic acid (radiolabelled) per 100 ml. The cloths
were than allowed to equilibrate for 3 hours.
AMENDED SHEET
C3580PC1 . 2 1 73 1 37
Each composition under test was applied to a fabric
square at ambient temperature at a level designed to give a
liquor to cloth ratio of 1:1. The contact time was varied
from 5 to 30 minutes to examine kinetic effects. The
cloth was then transferred, using tweezers, to an open
bottle containing 15 ml of water (20 French hard) held
within a shaker bath maintained at 25C. The cloth was
then rinsed for 2 minutes at a 100 rpm setting of the
shaker bath (this gave a gentle to and fro motion to the
rinse liquor within the bottle).
After rinsing the liquor was sampled with an automatic
pipette (3 x 1 ml aliquots). These aliquots were
transferred to plastic vials and were then mixed with 10 ml
quantities of scintillator solution prior to being counted
on a liquid scintillation counter. The counts
(disintegrations per minute, "DPMs") were used to calculate
the percentage removal for each soil component under each
condition examined. Standards were taken during the -
initial soiling procedure to give an average figure for theDPMs added in 0.18 ml of soiling solution.
Com~ositions
Liquid detergent compositions were prepared to the
formulations (in parts by weight) given in the tables that
follow. Soil removal (detergency) results are shown after
the tables of compositions.
The compositions of Examples ~ to 3 and Comparative
Examples A, X, P, D, M, N and H containing a solvent
(hexadecane) were in microemulsion form, while the
compositions of Comparative Examples B, Y, C, Q, E, F and
G, which did not contain a solvent, were not.
rJ~S\~
2173137
~0 95/27034 PCT/EP95/00990
The ingredients used may be identified as follows:
Novel (Trade Mark) 1012-52 ex Vista Chemicals: chain
length distribution as described previously, 4EO
2Dobanol (Trade Mark) 91-2.5 ex Shell: chain length
distribution as described previously, 2.5EO.
These two nonionic surfactants were used together in a
weight ratio of 3:1. The combined nonionic surfactant
contained about 75 wt% (based on the alcohol) of C10
material, and about 80 wt% (based on the alcohol) of ClO and
shorter-chain material. The HLB value was about 9.5.
3Novel (Trade Mark) 1412-4.4EO ex Vista Chemicals:
C12-144.4Eo.
~Sodium tripolyphosphate.
5Ethylenediamine tetracetic acid, tetrasodium salt.
6Copolymer of maleic and acrylic acids, sodium salt:
Sokalan (Trade Mark) CP5 ex BASF.
7Copolymer of polyvinyl acetate and itaconic acid, sodium
salt, as described and claimed in WO 93 23444A (Unilever~.
~ C3580PC1 , 21 7~37
Comparative Exam~les A, B, X and Y:
no builder
Example A B X Y
Nonionic:
CloEO41 7.5 7 5
CgllEO2.s 2.5 2.5
Cl2 l4Eo4 43 _ 10 . O 10 . O
Hexadecane 10.0 - 10.0
Water (20FH) 80.0 90.0 80.0 90.0
100.O 100.O 100.O 100.0
The soil removal results for Examples A and B
containing short-chain nonionic surfactant were as follows:
Soak/contact time Soil removal ($~
(minutes) Triolein Palmitic acid
A B A B
32.0 9.8 28.7 21.2
34.6 11.9 32.6 25.4
33.7 15.0 30.3 31.6
33.8 15.1 31.4 30.4
26.9 14.4 25.6 39.6
AMENDE~ SH~ET
21 73137
Ivo 95/27034 1 2 PCTIEP95/00990
These results show that, ln the absence of builder, in
the removal of triolein the microemulsion gave substantially
better soil removal throughout the 30-minute test period.
The microemulsion also offered a significant kinetic
ad~ntage over the non-microemulsion system. With palmitic
acid, the advantage was kinetic only.
The corresponding results for Comparative Examples X
and Y using longer-chain nonionic surfactant were as
~0 follows:
Soak/contact time Soil removal (~)
(minutes) Triolein Palmitic acid
X Y X Y
9.4 9.4 29.2 14.2
14.6 9.5 33.1 15.2
19.7 11.3 34.4 20.5
25.5 13.6 37.3 23.5
31.9 17.0 37.8 29.4
On triolein, the microemulsion system X finally gave
results comparable with those obtained from microemulsion
system 1, but required the full 30 minutes to do so; the
use of short-chain nonionic surfactant clearly gives a
significant kinetic advantage. The non-microemulsion
system Y was poor, comparable to the non-microemulsion
system A.
On palmitic acid, however, the longer-chain nonionic
surfactant apparently benefited more than the shorter-chain
material from microemulsification.
2 1 73 1 37
C3580PCl
Exam~le 1, Com~arative Exam~les C, P and O:
sodium tri~olY~hos~hate builder
Example 1 C P Q
Nonionic:
CloEO4l 7.5 7.5
CgllEO2.s- 2.5 2.5
Cl2-l~E4.4-' ~ 10.0 10.0
Hexadecane 10.0 - 10.0
STP4 0.8 0.9 0.8 0.9
Water (20FH) 80.0 90.0 80.0 90.0
100.8 100.9 100.8 100.9
The soil removal results for Examples 1 and C
containing short-chain nonionic surfactant were as follows:
Soak/contact time Soil removal (%)
(minutes) Triolein Palmitic acid
C 1 C
36.2 22.2 49.6 47.3
50.7 26.3 60.1 50.7
58.7 26.9 60.7 50.0
60.8 28.5 63.6 54.7
63.8 26.1 63.5 55.6
AMENDr~ SH,ET
~ C3580PC1 , 2 1 73 1 37
- 14 -
Comparison of these results with those of Comparative
Examples A and B shows that both systems performed better
in the presence of the highly efficient builder, sodium
tripolyphosphate. However, the difference in performance
between the microemulsion and the non-microemulsion was
substantially increased, very high figures being obtained
with the microemulsion. Also, palmitic acid removal was
always better with the microemulsion system than with the
comparative system.
The corresponding results for Comparative
Examples P and Q using longer-chain nonionic surfactant
were as follows:
Soak/contact time Soil removal (~)
(minutes) Triolein Palmitic acid
P Q P Q
7.5 20.8 46.5 37.1
12.3 26.0 51.6 42.0
17.7 31.1 51.7 44.8
22.9 33.1 54.8 49.0
39.5 34.8 55.9 53.8
On triolein, the microemulsion P gave significantly
worse results than the microemulsion 1, and was also slow
to reach the maximum value. Of the four systems only 1
gave really high values. The non-microemulsion systems Q
and C gave similar results, showing no benefit for the use
of short-chain nonionic surfactant in the non-microemulsion
system.
On palmitic acid, little difference was observed
between the various systems.
~EN~ S~LF~
~ C3580PC1 . 2 1 73 ~ 37
- IS -
Com~arative Exam~les D and E: EDTA builder
Example D E
Nonionic:
CloEO41 7.5 7 5
CgllEO2.s 2.5 2.5
Hexadecane 10.0
EDTA5 0.8 0.9
Water (20FH) 80.0 90.0
100.8 100.9
Soil removal results were as follows:
Soak/contact time Soil removal (%)
(minutes) TrioleinPalmitic acid
D E D E
32.0 16.4 44.5 39.7
45.0 17.0 48.7 40.7
45.6 19.3 46.2 45.7
48.4 21.2 47.4 46.2
36.0 18.8 44.3 53.4
These results show a similar pattern to that seen with
sodium tripolyphosphate builder, but the benefit was
smaller. With palmitic acid, only a kinetic advantage was
seen.
AMENDED SHEET
~ C3580PC1 2 1 73 1 37
The following Examples show that much better
detergency could be achieved using polymeric builders.
S ~xam~le 2, Com~arative Exam~les F and M:
acrvlate/maleate co~olvmer builder
Example 2 F M
10Nonionic:
C1oEO41 7.5 7.5
CgllEO2s 2.5 2.5
C1~-l4EOq. 43 - - 1 0 . O
Hexadecane 10.0 - 10.0
AA/MA6 0.8 0.9 0.8
Water (20FH) 80.0 90.0 80.0
, ---- ~~~~
100.8 100.9 100.8
The soil removal results were as follows:
.
Triolein Palmitic acid
2 F M 2 F M
41.4 12.5 6.0 49.4 27.2 39.0
10 53.4 16.5 8.5 54.1 34.3 41.6
15 56.2 17.1 12.6 56.4 36.4 45.6
20 59.8 18.6 18.6 59.8 37.4 49.6
30 58.7 19.2 33.6 62.1 42.7 55.0
These Examples show the benefits of a microemulsion
system and of the use of short-chain nonionic surfactant.
A~E~ Ds~EFT
C3580PC1 2 1 73 ~ 37
~xam~le 3, Com3arative Exam~les G and N:
~olY(vinvl acetate/itaconate) builder
Example 3 G N
Nonionic:
C1oEO41 7.5 7 5
Cg llE02 52 2.5 2.5
C12l~EO4.43 - - 10.0
Hexadecane 10.0 - 10.0
PVA/IA' 0.8 0.9 0.8
~ater (20FH) 80.0 90.0 80.0
____ ____ ____
100.8 100.9 100.8
The soil removal results were as follows:
Triolein Palmitic acid
3 G N 3 G N
32.3 16.0 3.4 52.3 33.9 41.4
45.5 17.9 5.3 61.6 41.4 43.8
50.3 20.7 7.9 63.4 45.3 47.1
58.2 20.213.6 67.0 47.4 49.5
64.3 20.230.1 64.7 48.4 53.8
These Examples show the benefits of a microemulsion
system and of the use of short-chain nonionic surfactant.
AMENDE~ SHFEJ
~ C3580PC1 2 i 73 1 37
~g
Com~arative Exam~le H: sodium citrate builder
Example H
Nonionic:
CloEO~1 7 5
Cg_ llE2 . 52 2.5
Hexadecane 10.0
Sodium citrate 0.8
Water (20FH) 80.0
100.8
Soil removal results were as follows:
Soak/contact time Soil removal (%)
(minutes) TrioleinPalmitic acid
42.0 31.6
41.9 33.0
39.7 35.1
40.8 35.9
38.3 38.9
These results, when compared with Examples 1-3, show
some benefit over an unbuilt system, but demonstrate
citrate to be a very much less effective builder in these
systems than are sodium tripolyphosphate or polymeric
builders.
Alf.E~.D SHE~
