EP1775338B1 - Solid soap with reduced cracking - Google Patents

Abstract

Solid soap piece (I) comprises thiosulfate salts (greater than 0.2%, preferably 0.5% and less than 5%), fatty acid salt (50-90%) and water (greater than 1%).

Description

The present invention relates to solid soaps having reduced cracking.

The desire for a clean and well-groomed appearance is probably as old as humanity. Impure skin and a neglected hair costume provide ideal breeding ground and home to pathogens and parasites of all kinds. The desire for personal hygiene was steadily strengthened, as in the 60s of the 20th Century in addition to the "classic" soap and liquid detergents formulated with newly developed synthetic surfactants could become. Since then, bathing and showering have become an indispensable part of our daily lives, and consumers nowadays have a multitude of products available for cleaning the various body parts. Despite the variety of products offered soap bars claim a not insignificant market share.

Surface-active substances - most prominently the alkali salts of higher fatty acids, ie the classic "soaps" - are amphiphilic substances that can emulsify organic non-polar substances in water.

In the body cleansing bar soaps play a major role, which are nowadays industrially produced by continuous saponification of free fatty acids with alkalis, concentrating the base soaps and spray drying. A distinction is made between real alkali soaps containing exclusively fatty acid salts and optionally still free fatty acids and so-called "combibars", bar soaps which in addition to fatty acid salts have other synthetic surfactants, usually fatty alcohol ether sulfates or fatty acid isethionates. A special position, however, take the Syndetstückseifen, so-called "Syndetbars", which are free of impurities except for fatty acid salts and contain only synthetic surfactants.

In Germany alone, several million pieces of soaps are sold every year for personal hygiene. However, the requirements of the market for these mass consumables are becoming ever higher: bar soaps not only have to cleanse the skin but also care for it, ie prevent it from drying out, degrease it and provide protection against outside influences.

Of course, it is expected that the soap is particularly gentle to the skin, but it should still give as much and creamy foam in the application and be characterized by a pleasant feeling on the skin during and after the application. In this context, manufacturers of bar soaps are constantly looking for new ingredients that meet this increased requirement profile.

In addition, soap bars tend to crack in the soap body during use many times and the edges of the cracks are often gray or dark discolored. While this does not affect the cleansing and care performance of the soaps, it does affect the visual and skin feel of using the soap bar. The aim is to remedy these evils and throughout the use optically aesthetic and sensory pleasant, i. provide smooth soap surfaces.

Main constituents are the alkali salts of the fatty acids of natural oils and fats, preferably the chain length C ₁₂ -C ₁₈ . Since lauric acid soaps foam particularly well, the lauric acid-rich coconut and palm kernel oils are preferred raw materials for the production of fine soap. The sodium salts of the fatty acid mixtures are solid, the potassium salts soft-pasty. For saponification, the dilute sodium hydroxide or potassium hydroxide solution is added to the fatty raw materials in a stoichiometric ratio so that an alkali excess of at most 0.05% is present in the finished soap. In many cases, the soaps are no longer produced directly from the fats, but from the fatty acids obtained by lipolysis.

Common soap supplements are fatty acids, fatty alcohols, lanolin, lecithin, vegetable oils, partial glycerides and other fat-like substances to restore the cleansed skin, antioxidants such as ascorbyl palmitate or tocopherol to prevent auto-oxidation of the soap (rancidity), complexing agent nitrilotriacetate to bind heavy metal traces that are the auto-oxidative Spoilage spoilage, perfume oils to obtain the desired scents, dyes for coloring the soap bars and, if desired, special additives.

• Toilettenseifen mit 20 - 50 % Kokosöl im Fettansatz, bis 5 % Rückfetter-Anteil und 0,5 - 2 % Parfümöl, sie bilden den größten Anteil der Feinseifen;
• Luxusseifen mit bis zu 5 % besonders kostbarer Parfümöle;
• Deoseifen mit Zusätzen desodorierender Wirkstoffe, wie z. B. 3,4,4'-Trichlorcarbanilid (Triclocarban);
• Cremeseifen mit besonders hohen Anteilen rückfettender und die Haut cremender Substanzen;
• Babyseifen mit guter Rückfettung und zusätzlich pflegenden Anteilen wie z. B. Kamille-Extrakten, allenfalls sehr schwach parfümiert;
• Hautschutzseifen mit hohen Anteilen rückfettender Substanzen sowie weiteren pflegenden und schützenden Zusätzen, wie z. B. Proteinen;
• Transparentseifen mit Zusätzen von Glycerin, Zucker u. a., welche die Kristallisation der Fettsäuresalze in der erstarrten Seifenschmelze verhindern und so ein transparentes Aussehen bewirken;
• Schwimmseifen mit einer Dichte < 1, hervorgerufen durch bei der Herstellung kontrolliert eingearbeitete Luftbläschen;
• Seifen mit abrasiven Zusätzen zur Reinigung stark verschmutzter Hände.

The most important types of fine soap are:

• Toilet soaps with 20 - 50% coconut oil in the fat mixture, up to 5% Rückfetter share and 0.5 - 2% perfume oil, they form the largest proportion of fine soaps;
• Luxury soaps with up to 5% of particularly precious perfume oils;
• Deo-soaps with additives of deodorizing agents such. B. 3,4,4'-trichlorocarbanilide (triclocarban);
• Cream soaps with particularly high levels of moisturizing and creaming substances;
• Baby soaps with good moisturizing and additional nourishing shares such. B. chamomile extracts, at best very poorly perfumed;
• Skin protection soaps with high levels of moisturizing substances as well as other nourishing and protective additives, such as: Proteins;
• Transparent soaps with additions of glycerine, sugar, etc., which prevent the crystallization of the fatty acid salts in the solidified soap melt and thus produce a transparent appearance;
• Floating soaps with a density <1, caused by air bubbles which are controlled during manufacture;
• Soaps with abrasive additives to clean heavily soiled hands.

When washing with soap, the pH in the wash liquor is 8-11. This alkalinity alters the natural acid mantle of the skin (pH 5 - 6). Although this is regenerated relatively quickly in normal skin, it can cause irritation in sensitive or damaged skin. The basis of syndet soaps are synthetic anionic surfactants, which can be processed with builders, backfats and other additives to soap-like pieces. Their pH can be varied within wide limits and is usually adjusted to neutral pH 7 or the acid mantle of the skin adjusted to pH 5.5. They have excellent cleaning power, foam in any water hardness, even in seawater, the proportion of lubricating additives must be much higher than normal soaps because of their intensive cleaning and degreasing effect. Their disadvantage is the relatively high price.

The font DE 103 18 325 A1 discloses a solid cleaning piece containing a combination of surfactants and elastomeric polymers.

The font EP 1 174 493 A1 discloses a molded soap product containing talc, certain fatty acid alkalis and moisturizing agents, which products are free of alkyl (oligo) glycosides.

The font DE 512428 discloses solid soaps with low fatty acid content below 80% with ammonium thiosulfate.

The font WO 03/085077 A1 discloses a molded soap product containing certain alkali fatty acid salts and pre-gelatinized, crosslinked starch derivatives.

A very large phenomenon that is often criticized by consumers for solid soaps is their tendency to form cracks in the soap bar during use. This can go into several small pieces until it decays.

1. Anlage:

Aufhängevorrichtung mit Drahthaken oder Fäden zum Aufhängen der zu prüfenden Seifenstücke.
Mit frischem Leitungswasser gefülltes Kunststoffrohr.
Auf eine Temperatur zwischen 21°C und 22°C und eine relative Luftfeuchtigkeit von 50 - 55 % klimatisierte(r) Raum/Kammer.
Es sind ausschließlich repräsentative Seifenstücke für die Prüfung einzusetzen. Die Seifenstücke müssen mindestens 24 Stunden alt sein.

Vorgehensweise:

Seifen mit Prägung müssen mit der glatteren Seite in das Wasser getaucht werden.
In eine der Flachseiten ist vertikal ein Loch zu bohren. Der Abstand zwischen dem Loch und einer der Breitseiten hat etwa 2 cm zu betragen. Der Abstand zwischen dem Loch und den beiden Schmalseiten sollte gleich groß sein.
Bei Rundseifen hat das Loch ebenfalls etwa 2 cm von der Kante beabstandet zu sein (siehe Figur 1)
Die Seife ist mit einem Drahthaken oder einem Faden an der Aufhängevorrichtung zu befestigen. Eine Hälfte der Seife muss im Wasser eingetaucht sein. Es ist sicherzustellen, dass die Breitseite der Seife parallel zur Wasseroberfläche ausgerichtet ist.
Prüfzeitraum: 12 Tage.
Tag 1: Die Seife muss vier Stunden lang bei Raumtemperatur im Wasser bleiben. Nach vier Stunden ist die Seife aus dem Wasser zu nehmen und an der Aufhängevorrichtung abtropfen zu lassen.
Trocknungszeitraum von 44 Stunden. Danach erste Bewertung.
Tag 3: Die Seife muss vier Stunden lang bei Raumtemperatur im Wasser bleiben. Nach vier Stunden ist die Seife aus dem Wasser zu nehmen und an der Aufhängevorrichtung abtropfen zu lassen.
Trocknungszeitraum von 44 Stunden. Danach zweite Bewertung.
Tag 5: Die Seife muss vier Stunden lang bei Raumtemperatur im Wasser bleiben. Nach vier Stunden ist die Seife aus dem Wasser zu nehmen und an der Aufhängevorrichtung abtropfen zu lassen.
Trocknungszeitraum von 68 Stunden. Danach dritte Bewertung.
Tag 8: Die Seife muss vier Stunden lang bei Raumtemperatur im Wasser bleiben. Nach vier Stunden ist die Seife aus dem Wasser zu nehmen und an der Aufhängevorrichtung abtropfen zu lassen.
Trocknungszeitraum von 44 Stunden. Danach vierte Bewertung.
Tag 10: Die Seife muss vier Stunden lang bei Raumtemperatur im Wasser bleiben. Nach vier Stunden ist die Seife aus dem Wasser zu nehmen und an der Aufhängevorrichtung abtropfen zu lassen.
Trocknungszeitraum von 44 Stunden. Danach fünfte und letzte Bewertung.

The cracking can be measured as follows:

1st plant:

Suspension device with wire hook or threads for suspending the soap bars to be tested.
Plastic pipe filled with fresh tap water.
At a temperature between 21 ° C and 22 ° C and a relative humidity of 50 - 55% air-conditioned room / chamber.
Only representative soap bars are to be used for the test. The soap bars must be at least 24 hours old.

Procedure :

Embossed soaps should be dipped in the water with the smoother side.
In one of the flat sides is to drill a hole vertically. The distance between the hole and one of the broad sides should be about 2 cm. The distance between the hole and the two narrow sides should be the same size.
For round soaps, the hole should also be spaced about 2 cm from the edge (see FIG. 1 )
The soap should be attached to the suspension device with a wire hook or a thread. One half of the soap must be submerged in the water. Make sure that the broad side of the soap is aligned parallel to the water surface.
Test period: 12 days.
Day 1: The soap must remain in the water for four hours at room temperature. After four hours, the soap should be removed from the water and drained on the suspension device.
Drying period of 44 hours. After that first rating.
Day 3: The soap must remain in the water for four hours at room temperature. After four hours, the soap should be removed from the water and drained on the suspension device.
Drying period of 44 hours. Then second rating.
Day 5: The soap must remain in the water for four hours at room temperature. After four hours, the soap should be removed from the water and drained on the suspension device.
Drying period of 68 hours. Afterwards third rating.
Day 8: The soap must remain in the water for four hours at room temperature. After four hours, the soap should be removed from the water and drained on the suspension device.
Drying period of 44 hours. Afterwards fourth rating.
Day 10: The soap must remain in the water for four hours at room temperature. After four hours, the soap should be removed from the water and drained on the suspension device.
Drying period of 44 hours. After that fifth and last rating.

2. Evaluation

The use of thiosulphate in concentrations up to 0.2% as a color stabilizer in solid soaps is common, but could have no way to solve the problem.

It was therefore the object of the present invention to eliminate the deficiencies of the prior art and to develop alkaline cleaning preparations with low cracking and a particularly good skin feel.

Surprisingly, it was found that by using thiosulfate in concentrations greater than 0.2% long-term stable soaps can be produced with significantly reduced cracking. An embodiment of the invention is therefore a solid soap bar containing more than 0.2% of a thiosulfate salt, preferably more than 0.3%, more preferably more than 0.5% and less than 5%, 50-90% fatty acid salt, water in an amount from 5 to 35% by weight and additional anionic surfactants less than 10%.

Even for the skilled person, predictions about the long-term stability of such systems and, in particular, influences on the cracking behavior of sticks are difficult to give, and thus the properties of this formulation are astonishing.

It is preferred if the pH of a 1% aqueous solution is greater than 8. This causes a soap-like skin feel after use.

It is preferred if the fatty acids from 50 to 95 wt .-% C ₁₆ -C ₁₈ fatty acids and from 5 to 50 wt .-% C ₁₂ -C ₁₄ fatty acids, particularly preferably from 50 to 85 wt .-% C ₁₆ -C ₁₈ fatty acids and from 10 to 50 wt .-% C ₁₂ -C ₁₄ fatty acids are composed. This gives soft, cosmetically pleasant soap bars with good foaming behavior.

It is preferred if in addition 1-10 wt .-% of free fatty acids having 12 to 22 carbon atoms are contained therein.

The soap bar according to the invention contains additional anionic surfactants in proportions by weight of less than 10%, preferably less than 5%, particularly preferably less than 2.5%. This causes a better foaming in hard water.

It is preferred if a soap bar according to the invention contains 1 to 99% by weight of fatty acids having 12 to 22 carbon atoms, in the form of their alkali soaps, in particular a basic soap, for example one whose soap components are composed of sodium tallowate, sodium cocoate and / or sodium Palmkernfettsäuresalz put together. This can be a nesonders inexpensive, yet high-quality soap produced. As fatty acids for the preparation of the basic soap are the linear fatty acids having 12 to 22 carbon atoms, eg. As the lauric, myristic, palmitic, stearic, arachin and behenic acid, but also the unsaturated fatty acids, eg. B. Palmitolein, oleic, linoleic, linolenic, arachidonic and erucic acid used. Preference is given to technical mixtures, such as are available from vegetable and animal fats and oils used, for. As coconut oil fatty acid and tallow fatty acid.

Particular preference is given to mixtures of coconut oil and tallow fatty acid slices, in particular a mixture of 50-95% by weight C ₁₆ -C ₁₈ tallow fatty acid and 5-50% by weight C ₁₂ -C ₁₄ keto fatty acid. Very particular preference is given to a mixture of 50-80% by weight of C ₁₆ -C ₁₈ tallow fatty acid and 20-50% by weight of C ₁₂ -C ₁₄ coconut fatty acid.

The fatty acids are used in the form of their alkali soap, usually as sodium soaps. The soaps can also be produced from the fats and oils directly by saponification (hydrolysis) with sodium hydroxide solution and separation of the glycerol. The shaped soap products according to the invention preferably contain an additional amount of 1-10% by weight of free fatty acids having 12-22 C atoms. These can be identical to the fatty acids of the basic soap and can be introduced into the basic soap by an appropriate alkali deficiency during saponification. Preferably, however, the free fatty acids are added after saponification and after concentration, before drying.

The soap bar contains water in an amount of 5-35% by weight. The water content is partly due to the manufacturing process, on the other hand, it has a favorable effect on the performance characteristics of the soap.

It is preferred if the soap bar has a melting point of more than 45 ° C. Thus, the soap bar is also suitable for the tropics.

It is further preferred if the thiosulfate salt or salts are selected from the group of inorganic alkali metal thiosulfates, preferably sodium thiosulfate.

Further, it is preferred if the soap bar according to the invention additives and / or auxiliaries, such. As synthetic surfactants, oil, emulsifiers, superfatting agents, fats, waxes, glycerol, stabilizers, film formers, cationic polymers, talc, pigments, vitamins, biogenic agents, preservatives, dyes and fragrances, inter alia, in a concentration of less than 10%, preferably smaller 5% more preferably less than 1% in the soap product. The invention also includes a soap bar according to the invention enclosed in a cushion made of water-insoluble non-woven, mesh or perforated foil, which is thus used. As a result, a completely new product form can be provided.

The invention also encompasses the use of thiosulfate salts to reduce soaps cracking.

Exemplary measurement results for soap bars containing 0.2% and 0.6% sodium thiosulfate:

Soap with 0.6% sodium thiosulfate:

• Neben den Pflege- und/ oder Reinigungseigenschaften stellt die Handhabung eines kosmetischen Produktes einen für den Verbraucher sehr wichtigen Punkt dar. Die hier beschriebene Formulierung verfügt über sehr gute Anwendungseigenschaften. Sie lässt sich auf die Haut gut aufbringen und nach der Anwendung einfach abspülen.
• Das Produkt weist eine sehr gute Langzeitstabilität auf. Diese garantiert über den gesamten Verwendungszeitraum eine gleich bleibende Produktqualität und Produktleistung.
• Sehr gute Schaum- und sehr gute Reinigungsleistung des Produktes.

The preparation according to the invention also has many advantages:

• In addition to the care and / or cleaning properties, the handling of a cosmetic product is a very important point for the consumer. The formulation described here has very good application properties. It can be applied to the skin well and simply rinse off after use.
• The product has a very good long-term stability. This guarantees consistent product quality and product performance over the entire period of use.
• Very good foam and very good cleaning performance of the product.

According to the invention may be included in the solid cleaning pieces such as "real" alkali soaps or Combibars elastomeric polymers.

For the purposes of the present invention, it is advantageous if the product according to the invention contains one or more complexing agents in a total concentration of 0.1 to 2.0% by weight and more preferably in a concentration of 0.2 to 1.0% by weight. , in each case based on the total weight of the preparation contains.

The complexing agent (s) can advantageously be selected from the group of the customary compounds, preference being given to at least one substance selected from the group consisting of tartaric acid and its anions, citric acid and its anions, aminopolycarboxylic acids and their anions (such as, for example, ethylenediaminetetraacetic acid (EDTA) and their anions, Tetrasodium iminodisuccinate (IDS), nitrilotriacetic acid (NTA) and their anions, hydroxyethylenediaminotriacetic acid (HOEDTA) and its anions, diethylenetaminopentaacetic acid (DPTA) and their anions, trans-1,2-diaminocyclohexanetetraacetic acid (CDTA) and their anions).

According to the invention, it is particularly preferred to use hydroxyethylenediaminotriacetic acid and, in particular, the sodium salt of hydroxyethylenediaminotriacetic acid (Na ₃ HEDTA) as complexing agent.

It is inventively advantageous if the product according to the invention one or more skin moisturizing agents in a concentration of 0.5 to 10 wt .-% and preferably in a concentration of 2.0 to 6.0 wt .-%, each based on the total weight of Preparation containing.

Skin moisturizing agents which are advantageous according to the invention are, for example, glycerol, lactic acid and / or lactates, in particular sodium lactate, butylene glycol, propylene glycol, biosaccharide gum-1, glycine soya, ethylhexyloxyglycerol, pyrrolidonecarboxylic acid and urea. Furthermore, it is particularly advantageous to use polymeric moisturizers from the group of water-soluble and / or water-swellable and / or water-gellable polysaccharides. Hyaluronic acid, chitosan and / or a fucose-rich polysaccharide, for example, which are filed in the Chemical Abstracts under the registration number 178463-23-5 and z. B. under the name Fucogel®1000 from the company SOLABIA S.A. is available.

Particularly preferred according to the invention is the use of glycerol as a skin moisturizer.

It is advantageous according to the invention if the product according to the invention contains abrasives (eg polyethylene scrubbing particles), glitter substances, effect substances, color streaks, gas bubbles (in particular air bubbles), pearlescent pigments, effect pigments, optical brighteners, mica, oil and / or emulsion blends ,

It is also advantageous for the purposes of the present invention if the cleaning piece according to the invention contains one or more dyes. In this case, in particular all known, water-soluble and approved for the cosmetics dyes can be added to the preparation.

Particularly advantageous preparations are also obtained when antioxidants are used as additives or active ingredients.

Further advantageous active ingredients in the context of the present invention are natural active ingredients and / or derivatives thereof, such as. Alpha-lipoic acid, phytoene, D-biotin, coenzyme Q10, alpha-glucosylrutin, carnitine, carnosine, natural and / or synthetic isoflavonoids, creatine, creatinine, taurine and / or β-alanine, and 8-hexadecene-1,16- dicarboxylic acid (dioic acid, CAS number 20701-68-2, provisional INCI name octadecenedioic acid), licochalcone A, ascorbic acid and its derivatives, vitamin E and its derivatives, vitamin A and its derivatives, y-oryzanol, panthenol and / or niacinamide ,

Another advantageous active ingredient according to the invention is, for example, polidocanol.

The amount of active ingredients (one or more compounds) in the preparations according to the invention is preferably 0.001 to 30 wt .-%, particularly preferably 0.05 to 20 wt .-%, in particular 0.1 to 10 wt .-%, based on the Total weight of the preparation.

Finally, the shaped soap products according to the invention may contain fragrances and other customary auxiliaries and additives in an amount of up to 5% by weight. Suitable auxiliaries are z. As binders or plasticizers. As such, e.g. Glycerol, fatty acid partial glycerides or fatty alcohols with 12 - 22 C atoms. The fatty alcohols may, for. B. as a byproduct of alkyl (oligo) glucosides are added together with these, if one uses the alkyl (oligo) glucosides as a crude product with a content of up to 50 wt .-% free fatty alcohol.

The preparation of solid cleaning pieces according to the invention can be carried out in the usual way for soaps. First of all, a base soap having a solids content of 25-50% by weight is prepared from fatty acid batch and sodium hydroxide solution and concentrated to a solids content of 50-70% by weight. In this z. B. 60% Grundseife can already, if desired or necessary, free fatty acid, an anionic surfactant and a complexing agent are mixed. Thereafter, the basic soap z. B. in a vacuum expansion dryer at 120 ° C to 130 ° C further dehydrated. During expansion, the soap spontaneously cools to temperatures below 60 ° C and solidifies. This fall soap noodles with a solids content of 73 - 85 wt .-% of.

The further processing of this basic soap then represents the finishing of fine soap.

It takes place in a soap mixer, in which a slurry of the alkyl (oligo) glucoside and the other auxiliaries and additives is mixed into the soap noodles. The basic soap noodles and the slurry of alkyl (oligo) glucoside and z. As fragrances, dyes, pigments and other auxiliaries in a screw mixer with perforated screens intensively mixed and finally discharged via an extruder and optionally supplied to a piece press when soap bars are to be produced.

However, solid cleaning items in the sense of the invention can also be present as noodles, needles, granules, extrudates, flakes and in any other form usual for soap products.

The soap products according to the invention are distinguished by a particularly pleasant feeling on the skin during and after the wash. The cracking that often occurs during use is significantly reduced in the soap products according to the invention. These two advantageous properties meet consumer needs and represent a significant improvement in daily hygiene for the end user.

Examples Soap making:

The basic soap noodles are dosed with the other components in a conventional soap mixer (screw mixer with perforated sieve), homogenized by repeated mixing, discharged via an extruder, cut and processed in the usual way to pieces.

Basic soaps:

Wt .-% Wt .-% Wt .-% Wt .-% Wt .-% Wt .-% Wt .-% sodium tallowate 68.0 68.0 65.0 0 68.0 72,25 76.5 sodium cocoate 0 17.0 17.0 82.0 17.0 12.75 8.5 Sodium palm kernel oil 17.0 0 0 0 0 0 0 water 11.0 11.0 12.0 12.0 11.0 11.0 11.0 sodium chloride 0.5 0.5 0.5 0.5 0.5 0.5 0.5 ethylenediaminetetraacetic 0 0 0.2 0 0 0 0 Natriumetidronat 0.1 0.1 0 0.1 0.1 0.1 0.1 glycerin 2.5 2.5 0.5 2.5 2.5 2.5 2.5 Sodium palm kernel fatty acid salts ad 100.0 ad 100.0 ad 100.0 ad 100.0 ad 100.0 ad 100.0 ad 100.0

Bars of soap:

Comparative Examples Weight% Comparative Examples Weight% Comparative Examples Weight% Comparative Examples Weight% Comparative Examples Weight% Wool alcohol 0.10 0.10 0.10 0.00 0.10 basic soaps 93,50 96,40 85.90 91.00 92,50 paraffin oil 1.50 1.00 0.50 1.00 1.00 Polyethylene glycol-150 0.00 0.00 0.00 2.00 0.00 talc 0.00 0.00 5.00 0.00 0.00 Perfume 1.00 1.00 0.70 2.00 0.50 sodium thiosulfate 0.30 0.40 1.00 0.40 0.40 Natural oils 0.20 0.20 0.10 0.00 0.20 Titanium dioxide 0.40 0.40 0.40 0.20 0.40 dye 12:01 0.00 0.05 0.00 0.00 Disteardimoniumhectorit 0.03 0.03 0.05 0.00 0.03 octyldodecanol 0.00 0.50 0.50 0.50 0.50 polyethylene 0.00 0.00 0.10 0.00 0.20 Licorice extract 0.00 0.10 0.00 0.20 0.00 water ad 100.0 ad 100.0 ad 100.00 ad 100.0 ad 100.0 Comparative Examples Weight% Comparative Examples Weight% Comparative Examples Weight% Comparative Examples Weight% Comparative Examples Weight% Wool alcohol 0.10 0.10 0.10 0.00 0.10 basic soaps 83,50 94,40 87,00 93,00 92,50 paraffin oil 1.50 1.00 0.50 1.00 1.00 zeolite 3.00 0.00 0.00 2.00 0.00 talc 5.00 0.00 5.00 0.00 0.00 Perfume 1.00 1.00 0.70 2.00 0.50 sodium thiosulfate 2.0 0.40 1.00 0.40 0.40 Natural oils 0.20 0.20 0.10 0.00 0.20 Titanium dioxide 0.80 0.40 0.00 0.20 0.40 dye 0.00 0.10 0.00 0.00 0.05 Disteardimoniumhectorit 0.03 0.03 0.05 0.00 0.03 octyldodecanol 0.50 0.50 0.50 0.50 0.50 niacinamide 0.00 0.50 1.00 0.00 0.20 zinc oxide 0.00 0.00 1.00 0.00 0.50 Hydroxypropyl starch phosphate 0.00 0.00 0.00 0.00 3.00 Sodium lauryl ether sulfate 2.00 0.00 0.00 0.00 0.00 water ad 100.0 ad 100.0 ad 100.00 ad 100.0 ad 100.0

Claims (9)

1. Solid soap bar comprising more than 0.2% of a thiosulphate salt, 50 - 90% of fatty acid salt, water in an amount of 5 - 35% by weight and additional anionic surfactants less than 10 %.
2. Soap bar according to Claim 1, characterized in that the pH of a 1 % strength aqueous solution is greater than 8.
3. Soap bar according to one of the preceding claims, characterized in that the fatty acids are composed of 50 - 95% by weight of C₁₆-C₁₈-fafty acids and of 5 - 50% by weight of C₁₂-C₁₄-fatty acids, preferably characterized in that the fatty acids are composed of 50 - 85% by weight of C₁₆-C₁₈-fatty acids and of 10 - 50% by weight of C₁₂-C₁₄-fatty acids.
4. Soap bar according to one of the preceding claims, characterized in that additionally 1 - 10% by weight of free fatty acids having 12 to 22 carbon atoms are present.
5. Soap bar according to one of the preceding claims, characterized in that it comprises 1 - 99 % by weight of fatty acids having 12-22 carbon atoms in the form of their alkali soaps.
6. Soap bar according to one of the preceding claims, characterized in that the melting point is greater than 45°C.
7. Soap bar according to one of the preceding claims, characterized in that the thiosulphate salt or salts are selected from the group of inorganic alkali metal thiosulphates, preferably sodium thiosulphate.
8. Soap bar according to one of the preceding claims, characterized in that it is enclosed in a pad made of water-insoluble nonwoven, netting or perforated film.
9. Use of thiosulphate salts for reducing cracking in soaps according to one of the preceding claims.

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