Cleaning compositions for solid surfaces – auxiliary compositions – Cleaning compositions or processes of preparing – For cleaning a specific substrate or removing a specific...
Reexamination Certificate
2000-05-18
2001-10-09
Ogden, Necholus (Department: 1751)
Cleaning compositions for solid surfaces, auxiliary compositions
Cleaning compositions or processes of preparing
For cleaning a specific substrate or removing a specific...
C510S153000, C510S155000, C510S156000
Reexamination Certificate
active
06300297
ABSTRACT:
BACKGROUND OF THE INVENTION
This invention relates to new bar soaps which contain anionic surfactants of the fatty acid polyglycol ester sulfate and fatty acid salt type as key components.
Modern bar soaps, more especially toilet soaps, are normally based on mixtures of bovine tallow and coconut oil in a ratio of about 9:1. This fatty mixture is hydrolyzed by addition of sodium hydroxide to the basic soap to which other additives, for example moisturizers, fillers and binders, superfatting agents, dyes and perfumes, etc., are added. Standard toilet soaps contain about 80% fatty acid salts, 10% water and auxiliaries and additives to 100%. The large number of products available to the consumer reflect the keen market interest, but nevertheless make it clear that there is a constant need among consumers for further improved products which are distinguished in particular by improved dermatological compatibility, greater foaming power, greater creaminess, improved refatting, rinse-off behavior, skin feel and the like. By contrast, soap manufacturers are looking for soap formulations which lead, for example, to bars with greater fracture resistance or which allow certain surfactants, for example alkyl sulfates, to be incorporated without difficulty. An overview on this subject can be found, for example, in J. Am. Oil. Chem. Soc. 59, 442 (1982).
So far as the manufacture of bar soaps is concerned, it is possible to look back on a very large number of processes from the prior art. A distinction has to be made in this regard between synthetic “soap-free” soaps, so-called syndets, and in particular combinations of fatty acid salts and synthetic surfactants (“combination bars”). According to EP-A 0 176 330 (Unilever) for example, combination bars are produced by combining fatty acid soaps with salts of isethionic acid. The use of fatty acid isethionates as a synthetic constituent of combination bars is known from EP-A 0 189 332, EP-A 0 472 320 and EP-A 0 508 006 (Unilever).
However, there is a constant need on the market for products with improved properties. In particular, there is a demand for bar soaps which produce a richer and creamier foam than known products and which, in addition, show improved dermatological compatibility. In addition, the soaps should leave the skin with an improved feel and should have a reduced tendency to take up water and to develop cracks. Accordingly, the problem addressed by the present invention was to provide bar soaps that would satisfy the complex requirement profile mentioned above.
DESCRIPTION OF THE INVENTION
The present invention relates to bar soaps containing
(a) 1 to 60, preferably 5 to 15% by weight fatty acid polyglycol ester sulfates,
(b) 10 to 35, preferably 5 to 30% by weight fatty acid salts,
(c) 0 to 40, preferably 1 to 30% by weight anionic, nonionic or amphoteric co-surfactants,
(d) 0 to 10, preferably 1 to 8% by weight fatty acids and
(e) 0 to 40, preferably 1 to 30% by weight water-soluble structurants,
with the proviso that the quantities shown add up to 100% by weight, optionally with water and other typical auxiliaries and additives.
It has surprisingly been found that the bar soaps according to the invention not only produce a particularly stable and creamy foam, they also show improved dermatological compatibility, have an increased water retention capacity on the skin (skin moisture) and a reduced tendency to take up water. The invention includes the observation that the combination of the fatty acid polyglycol ester sulfates with other surfactants, more particularly of the alkyl and/or alkenyl oligoglycoside, fatty add-N-alkyl poly-hydroxyalkyl amide, monoglyceride (ether) sulfate or betaine type or mixtures thereof, leads to bar soaps with further improved properties.
Fatty Acid Polyglycol Ester Sulfates
Fatty acid polyglycol ester sulfates, which form component (a) and preferably correspond to formula (I):
R
1
COO(AO)
x
SO
3
X (I)
in which R
1
CO is a linear or branched, saturated or unsaturated acyl group containing 6 to 22 carbon atoms, x has an average value of 1 to 3 and AO is a CH
2
CH
2
O—, CH
2
CH(CH
3
)O— and/or CH(CH
3
)CH
2
O group and X is an alkali and/or alkaline earth metal, ammonium, alkylammonium, alkanolammonium or glucammonium, are known anionic surfactants and are produced by sulfation of the corresponding fatty acid polyglycol esters which, in turn, are obtainable by the relevant preparative methods of organic chemistry. To this end, ethylene oxide, propylene oxide or a mixture thereof is added—in random or block distribution - onto the corresponding fatty acids in the presence of an acid as catalyst, but preferably in the presence of bases, for example sodium methylate or calcined hydrotalcite. If a degree of alkoxylation of 1 is required, the intermediate products may also be prepared by esterification of the fatty acids with a corresponding alkylene glycol. The sulfation of the fatty acid polyglycol esters may be carried out in known manner with chlorosulfonic acid or, preferably, gaseous sulfur trioxide, the molar ratio of fatty add glycol ester to sulfating agent being in the range from 1:0.95 to 1:1.2 and preferably in the range from 1:1 to 1:1.1 and the reaction temperature being in the range from 30 to 80° C. and preferably in the range from 50 to 60° C. The fatty acid polyglycol esters may also be undersulfated, i.e. the sulfating agent may be used in far less than the quantity which would be stoichiometrically necessary for a complete reaction. If, for example, the fatty acid polyglycol ester and sulfating agent are used in a molar ratio of 1:0.5 to 1:0.95, mixtures of fatty acid polyglycol ester sulfates and fatty acid polyglycol esters, which are also advantageous for a whole range of applications, are obtained. In order to avoid hydrolysis, it is very important to carry out the neutralization step at a pH value in the range from 5 to 9 and preferably in the range from 7 to 8. Typical examples of suitable starting materials are the addition products of 1 to 3 moles of ethylene oxide and/or propylene oxide, but preferably the addition products of 1 mole of ethylene oxide or 1 mole of propylene oxide with caproic acid, caprylic acid, 2-ethylhexanoic add, capric acid, lauric acid, isotridecanoic acid, myristic acid, palmitic add, palmitoleic acid, stearic acid, isostearic acid, oleic acid, elaidic acid, petroselic acid, linoleic acid, linolenic add, elaeostearic acid, arachic acid, gadoleic acid, behenic acid and erucic acid and technical mixtures thereof, which are then sulfated and neutralized as described above. A preferred embodiment of the invention is characterized by the use of fatty acid polyglycol ester sulfates corresponding to formula (I), in which R
1
CO is an acyl group containing 12 to 18 carbon atoms, x has an average value of 1 or 2, AO represents a CH
2
CH
2
O group and X is sodium or ammonium, such as for example lauric acid+1EO sulfate sodium salt, lauric acid+1EO sulfate ammonium salt, cocofatty add+1EO sulfate sodium salt, cocofatty acid+1EO sulfate ammonium salt, tallow fatty acid+1EO sulfate sodium salt, tallow fatty acid+1EO sulfate ammonium salt and mixtures thereof.
Fatty Acid Salts
Suitable fatty acid salts, which form component (b), are the alkali metal salts of fatty acids containing 6 to 22 and preferably 12 to 18 carbon atoms. Typical examples are the sodium or potassium salts of lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid and technical mixtures thereof such as, for example, cocofatty acid, palm kernel fatty acid, palm oil fatty acid and tallow fatty acid.
Alkyl and/or Alkenyl Oligoglycoside
Alkyl and alkenyl oligoglycosides, which may be present as optional surfactant component (c2), are known nonionic surfactants corresponding to formula (II ):
R
2
O—[G]
p
(II)
in which R
2
is an alkyl and/or alkenyl radical containing 4 to 22 carbon atoms, G is a sugar unit containing 5 or 6 carbon atoms and p is a number of 1 to 10. They may be obtained by the relevant methods of preparat
Fabry Bernd
Hensen Hermann
Seipel Werner
Cognis Deutschland GmbH
Drach John E.
Ogden Necholus
Trzaska Steven J.
LandOfFree
Hard soap containing fatty acid polyglycol ester sulphates does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hard soap containing fatty acid polyglycol ester sulphates, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hard soap containing fatty acid polyglycol ester sulphates will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2611418