SE439646B - COMPOSITION FOR THE PREPARATION OF TOILET SOAPS IN PIECE AND PROCEDURE FOR PREPARING THE COMPOSITION - Google Patents

Description

7807559-5 foam and which gives an extremely comfortable feeling both during use and after use. When comparing commercial greased toilet soaps, which are believed to be made according to the instructions given in U.S. Pat. No. 3,576,749, it was found that the new soaps of the present invention are highly preferred by consumers with respect to the nature of the foam. and other properties.

The soaps are solid and have a high ability not to become sticky or sticky without the need to incorporate added sodium chloride and without the need to use high rolling temperatures.

The composition according to the invention is characterized in that it essentially comprises sodium soap of higher fatty acids having 8 to 20 carbon atoms, 6 to 12% of higher fat fatty acids having 8 to 20 carbon atoms, 1 to 4% of poly- (ethylene oxide) having a molecular weight in the range from 100,000 to 5,000,000, and 5 - 18% water.

It has also been found that poly- (ethylene oxide) -containing overfat soaps, which have a particularly good ability not to stick or smear, comprise a sodium soap of about equal proportions of coconut fatty acids and tallow fatty acids overfat with about equal amounts of coconut fatty acids and stearic acid as is apparent, for example, from the information provided in Example 1 below.

Soap is prepared in a conventional manner by saponification of fatty acids or fatty esters (eg fats and oils) by either a "kettle" process or a continuous saponification technique as specified in the "Encyclopedia of Chemical Technology" (2nd edition) vol . 18 sidorna 415 - 425, som uppger att "the end product of both the kettle and continuous saponi- fication procedures is a neat soap containing approximately 30% water ...... The 30% water content of neat soap must be reduced to 10 - 15% before shaping into bars ..... 3 7807559-5 Soaps or soap bars have been produced commercially by adding powdered poly- (ethylene oxide) to soap flakes in a soap mixer, such addition requiring special precautions to avoid the formation The use of high molecular weight poly- (ethylene resin) in synthetic detergent rods, which may contain some amount of soap component, has been described and it has been suggested that the resin may be melted in combination with soap, detergent base or other constituents, after which the other material is incorporated into the melt (see Davidson and Sittig "Water Soluble Resins" published 1962, pages l97- -l98). When attempts were made to incorporate about 2% powdered poly (ethylene oxide) in a pure soap containing about 30% water ("kettle soap"), a mixture was obtained which was lumpy and poorly dispersed and not pumpable.

According to another aspect of the present invention, it has been found that an excellent or superior mixture is obtained by incorporating poly- (ethylene oxide), suitably in powder form, in a melt of all or part of the amount of the higher fatty acids used for greasing of the soap. The best results are obtained when this mixture also contains a small amount of water. As shown in Example 3 below, the presence of water has a marked effect on the nature of the mixture of fatty acid and high molecular weight poly- (ethylene oxide), which significantly reduces its viscosity, and the presence of water tends to opacify the mixture, which may indicate that a dispersion of type water-in-oil is formed. The aqueous mixture can be pumped with ease and its viscosity is well below the upper viscosity limit (which is about 7,000 or 8,000 cps for materials that can be easily and simply handled with standard reciprocating pumps. It can thus be easily pumped to blend with the kettle soap. The poly (ethylene oxide) -containing bars of soap prepared according to this method have excellent properties, they foam well, have a particularly pleasant feeling during and after use, have a good ability not to become sticky and an ability to resist wet cracking. The application of the present invention makes it possible to produce toilet soaps which give a rich and creamy, but only moderately lathery foam and which are solid and have the ability to resist sticking and cracking during use.

The following examples are provided to further illustrate the present invention. In the specification and claims, all amounts and proportions are by weight unless otherwise indicated.

Example 1 (a) 4.5 parts of stearic acid and 4.5 parts of coconut fatty acids were melted together at a temperature of 80 ° C in a vessel equipped with a stirrer. 1.8 parts of a high molecular weight poly- (ethylene oxide) ("Polyox WRS N-750" sold by Union Carbide and having a molecular weight of about 300,000, a viscosity - measured for a 5% solution in water - of about 550-900 eps at 2 ° C and a melting point in the vicinity of 65%) are added to the melt with stirring while keeping the mixture at a temperature of about 80 ° C. This mixture is then mixed with a cauldron soap (with a temperature of 70 ° C) in such proportions that the resulting mixture contains about 75 parts of sodium soap (expressed as anhydrous soap), 4.5 parts of the added stearic acid, 4.5 parts of the added coconut fatty acids and 1.8 parts of the poly (ethylene oxide) caustic soap are prepared by saponifying a 50/50 mixture of coconut oil and tallow with sodium hydroxide solution, extracting the resulting glycerin, "washing" with electrolyte solution and removal of high-electrolytic black soap layers, which measures are entirely conventional in the production of cauldron soaps. The kettle soap produced contains about 27 - 32% (eg 30%) water, up to about 1% (eg 0.5%) glycerol, up to about 0.3% (eg 0.1%) NaOH, up to about 1% (eg 0.7%) NaCl. The ingredients are stirred together for a few minutes and the mixture is then formed into dried soap flakes containing about 10% moisture by pumping the hot soap mixture onto a cooled roll, forming a thin film on the roll, shaking off slices, flakes or strips. and then dry these. The slices or flakes are then mixed with paint and perfume (e.g. 0.7% TiO 2 and 1.5% perfume) in a conventional manner in a soap mixer at about room temperature, after which they are rolled to be homogenized (e.g. at a temperature of about 15 - 35 ° C), and the rolled product is then sprayed in bar form by means of a conventional soap extruder (eg at a temperature of about 20 - 5000, (eg 40 ° C), which strand is then cut into cakes The surfaces of these cakes are cooled and the cakes are pressed to the desired shapes (eg in a mandrel press). (B) Section (a) is repeated except that instead of using 4.5 parts of stearic acid and 4.5 parts of coconut fatty acids 9 parts of stearic acid (c) Section (a) is repeated except that instead of using 4.5 parts of stearic acid and 4.5 parts of coconut fatty acids, 9 parts of coconut fatty acids were used.

When testing the soaps (after aging for at least 3 days) the following results were obtained: Mushroom foam Loose layer Removal- Hydration Cracking (17 hours) Ice (2 hours) Loss in.% 35% 37, s ° c increase in f. .

Number of strokes Index (a) 60 1.5 2.6 16.1 12.5 18 (b) 80 3.5 2.2 l8.8 11.6 15 (c) 68 5.2 l8.7 19.6 10.8 0 In the sponge foam test, which measures the speed of foam formation, the flat surface of the soaps is rubbed alternately with a sponge and dipped in a bowl of water (with a hardness level of 125 ppm and a temperature of 35oC). The up and down movement of the foaming machine provides the number of strokes required to form a continuous ring of foam in the bowl. The smaller the number of strokes 7so1559-s 6 obtained, the faster the foam is formed. In the experiment with a loose layer, the soap pieces are placed flat with one side immersed in a petri dish for 17 hours, after which time the soft, mushy soap is removed with the fingers. The percentage weight loss as a loose layer is stated. In the abrasion test, the bar of soap is immersed in water with 260 strokes (about 10 minutes) on the lathering machine, and the amount of soap lost is measured. In the hydration test, the soaps are completely immersed in tap water for two hours and the weight gain is determined. The crack index value is an estimate based on the number and severity of cracks in an experiment, in which the soap bars are planed off on one side to half their original sizes, after which they are placed under tap water (about 100 ppm hardness) for one hour, remove and hang to dry in air until no sign of free water remains on the surfaces of the soap bars (usually overnight).

The bar of soap according to section (a) shows unexpectedly rapid foam formation, unexpectedly low loss in the loose layer test and unexpectedly low abrasion loss and a fairly acceptable value for crack formation.

Example 2 Soaps are prepared according to Example 1 (a) except that they also contain 0.5% lanolin with and without 0.5% sodium caseinate in solid form, these ingredients being incorporated into the hot mixture of fatty acid and poly- ( ethylene oxide) before its mixing with the caustic soap.

Example 3 Example 1 (a) is repeated except that the following procedure is used in the manufacture of the mixture mixed with the cauldron soap. Five parts of commercial stearic acid (melting point 54 ° C) and five parts of coconut fatty acids (melting point ZSOC, iodine value 6) were melted together at a temperature of about 10 ° C. A portion of the powdered high molecular weight poly (ethylene oxide) ("Polyox WSR N-750", m.p. about 65 DEG C.) is added to the melt with stirring. The viscosity of the mixture at 10 ° C is about 750 cps, at 88 ° C it is about 4,000 eps and at 54 ° C it is about 5,000 eps (as determined by a Brookfield viscometer).

An additional portion of the same Polyox material is then added with stirring. The viscosity of the mixture is about 18,000 cps at 94 ° C, about 19,000 cps at 88 ° C, about 33,500 cps at 66 ° C and about 42,500 eps at 54 ° C.

Then 0.5 parts of lanolin are added with stirring. The resulting mixture now has a viscosity of about 15,000 cps at 94 ° C and a similar viscosity at 70 ° C.

As the next measure, some water is added. As a result of this addition, the previously clear mixture becomes cloudy or opaque. Its viscosity is about 5,000 cps at 77 ° C, about 4,000 cps at 71 ° C and about 3,250 cps at 50-63 ° C.

Then some more water is added with stirring.

The resulting mixture has a viscosity of about 2,250 eps at s4 ° c, 1,500 eps at s1 ° c, 930 eps at 71 ° c, 470 eps at 67 ° c, 234 eps at 60 ° c and 114 eps at 52 ° c.

Then 2.5 parts of a solution of sodium caseinate (containing 20% casein) are added. The resulting mixture is white. Its viscosity is about 2,900 cps at 81 ° C, 2,520 cps at 71 ° C, 1,700 eps at ae ° c and 1,800 eps at e0 ° c.

It appears that the addition of the water gives a mixture whose viscosity at, for example, 70 ° C has been reduced to a large extent (eg to well below half the value of the mixture before the addition of the water). The mixtures containing water also show a remarkable decrease in the viscosity with decreasing temperature (eg when the temperature is lowered, from 70 ° C or 80 ° C, with 10 ° C the viscosity drops well above 10%). The mixture obtained above is pumped at a temperature of about 60-85 ° C into a mixing vessel containing cauldron soap (having a temperature of 70 ° C) in such proportions that the resulting mixture contains about 75 parts of sodium. the soap unshaken as anhydrous soap), 4.5 parts of the added stearic acid, 4.5 and 1.8 parts of the poly (ethylene oxide).

Example 4 Example 1 (a) is repeated except that in the preparation of said resulting mixture 10 parts of stearic acid are melted and 2 parts of the poly (ethylene oxide) of Example 1 are added to the melt, after which 1.5 parts of water are added while stirring the mixture and maintained at about 70-90 ° C.

Example 5 Example 4 is repeated except that coconut fatty acids are used instead of stearic acid.

In the aqueous mixture of poly (ethylene oxide) and higher fatty acids there are preferably about 2 to 20 (more preferably about 4 to 8) parts of the fatty acids per part of poly (ethylene oxide) and about 0.5 to 5 (more preferably about 1 - 2) parts water per part poly- (ethylene oxide).

It is preferred that the amount of moisture in the ingredients added to the kettle soap be such that the moisture soap ratio is maintained below about 33:67 (such as about 27:73 - 32:68) to minimize the formation of less desirable gel phase in gel form.

It is desirable, especially in formulations containing relatively large amounts of coconut fatty acids (as in Example 1a), to perform drying to a moisture content below about 18%, preferably from about 5% to 12%, to reduce the tendency to stickiness. during later mixing (eg in the mixer) or processing. For the same reason, it is desirable to use relatively low extruder temperatures, to cool and dry the outside of the soap bars before pressing in the press and to lubricate the press (eg with an aqueous solution containing 16% NaCl and 25% glycerol, which is then blown off). from the surfaces of the pressed pieces of soap).

The high molecular weight poly (ethylene oxide) has an average molecular weight of at least about 100,000. Examples of such compounds are those sold by the Union Carbide Company under the trademark "Polyox".

These polymers are nonionic materials that are soluble in water and their molecular weights range from about 100,000 to about 5,000,000 or more. It is preferred to use polymers having average molecular weights below 1,000,000, more preferably not exceeding about 600,000, such as about 300,000-400,000.

For the material that has an average molecular weight of about 300,000, a proportion close to 2% has given excellent results. This material with a molecular weight of 300,000 (sold as Polyox WSR N-750) has a viscosity at 25 ° C, for a 2% aqueous solution, of about 40 centipois (Brookfield Spindle No. 1 VR110 rpm) and for a 5% In solution, this viscosity is about 600 - 1,000 centipois. The use of, for example, 2% of extremely high molecular weight poly (ethylene oxide), for example with an average molecular weight of 4,000,000, causes the foam to become slimy, which is less desirable. According to the manufacturer, the Polyox materials typically have a pH of about 10 (eg in 5% solution). Soap typically has a pH of about 10 (eg 10.2) in 1% aqueous solution, while the greased soaps of the present invention generally have lower pH values, such as about 9.5.

The poly (ethylene oxide) is generally supplied as a powder and typically has the following particle size distribution when a sample of the powder is sieved through a series of sieves, expressed as weight percent of retained material on the designated numbered sieves according to US Sieve Series Standard: No. 20 - 5.2%, no. 40 - 31.2%, no. 60 - 20.7%, no. 10 - 16.7%, the remainder passing through sieve No. 100. It is often preferred to use a poly- (ethylene oxide) having a finer particle size and having the following distribution measured as above: 20 - 0.5 z, 7807559-5 10 O '51 No. 40 - 13%, no. 60 - 13 No. 100 - 13.9%, the remainder passing through No. 100-sole.

The best results have thus far been obtained using a soap prepared by saponifying a mixture of about equal parts of tallow and coconut oil. In general, it is preferred to use a ratio of tallow to coconut oil in the range of from about 2: 1 to 1: 2, such as 3: 2 or 2: 3.

Before mixing the cauldron soap with the various constituents, it is preferred to stabilize the cauldron soap by incorporating, for example, about 0.06% SnCl 4 and 0.024% tetrasodium salt of ethylenediaminetetraacetic acid, these constituents being added as aqueous solutions.

As far as the fatty acid is concerned, the best results have so far been obtained when it comprises approximately equal proportions of stearic acid and coconut fatty acids. In general, it is preferred to use these acids in a ratio ranging from about 2: 1 to 1: 2, such as 3: 2 or 2: 3. The total amount of fatty acids in the soap is generally less than about 15%.

It is to be understood that cation exchange of Na and H may occur during the preparation of the mixture of the soap and fatty acids and that it is most appropriate to express the distribution of the chain lengths in the mixture in terms which combine the saponified and unsaponified fatty acids. Typical distributions expressed in this way in soaps according to the present invention are given in the table below: / f '11 7807559-5 Number of carbon atoms in the fatty acid Percent (the fatty acid is saturated unless otherwise stated) ab 8 3.1 2.8 10 2, 9 2.6 12 24.3 21.5 14 11.0 10.5 14 monounsaturated 0.2 0.5 15 0.2 0.3 15 monounsaturated - - 16 19.0 18.6 16 monounsaturated 1.0 1 .7 17 0.6 0.4 17 monounsaturated 0.3 - 18 13.4 12.6 18 monounsaturated 21.6 25.9 18 diounsaturated 2.1 2.1 18 triunsaturated 0.3 * 0.3 Summary up to C12 30.3 26.9 C16 - C14 31.4 31.6 C - C 38.3 41.3 l8 17 7307559-5 12 As regards the moisture content below about 12% during preparation, it should be noted that during use or during storage after the preparation, the moisture content can increase (see, for example, the hydration values in Example 1). Preliminary results, however, indicate that the soaps have a significantly lower tendency to hydrate than commercial greased soaps.

Conventional kettle soap contains up to about 1% (eg 0.7%) sodium chloride. The products of the present invention have a good ability not to become smeary without the need to add sodium chloride, although it is to be understood that such additives (as in U.S. Pat. No. 3,576,749) do not fall outside the further scope of the invention. The soaps of the present invention have good hardness comparable to or greater than the hardness of ordinary toilet soap at 32.2 ° C, when the rolling is performed at conventional relatively low temperatures (i.e. the dietary hardness of the soaps at 32.2 ° C is above about 85, e.g., 90-92), and there is no need to use the higher rolling temperatures disclosed in the said U.S. patent, although it is to be understood that the use of such rolling temperatures does not fall outside the further scope of the invention.

The fatty acids in the soap and superfat and the relative proportions of the various acids may be of the type described in U.S. Pat. No. 3,576,749. These fatty acids may thus contain about 8 to 20 carbon atoms. The fatty acid may contain fatty acids that have an odd number of carbon atoms. Thus, a fatty acid mixture containing equal proportions (one third of each) of C11-, C12- and C13-saturated fatty acids (Monsanto CR-1157) can be used.

The soap bars of the present invention may contain conventional ingredients such as opacifying agents (eg 0.4% titanium dioxide added to the soap mixer), lanolin (eg 0.5% added to the pure soap, preferably in admixture with excess fat), glycerin (eg 1% added to the soap blender or to the pure soap), soap perfume (eg 1 - 3%, such as 1.5 - 2%, which is added to the soap blender), antioxidants (t eg 0.02% di-t-butyl-p--cresol or BHT added to the pure soap), protein (eg 0.5% sodium caseinate added to the pure soap or as an aqueous solution in the soap mixer) . Antibacterial agents or germicides such as those mentioned in U.S. Pat. Nos. 3,576,749 and 3,598,746 may be incorporated. It is within the further scope of the invention to aerate the soaps in a manner well known in the art for obtaining soaps with lower density (liquid), such as those having a specific gravity of about 0.8 g / cm 3.

The toilet soaps have a size that extends from the relatively small hotel size (weighing about 20 - 30 g) to the regular size (about 100 g) up to the bath size (about 150 g) and further up to the extra large size (about 200 g). The soaps of the present invention may be of such sizes, especially in the range of from about 100 to 200 g.

As mentioned above, the poly (ethylene oxide) can be incorporated in two steps, one part (such as about half or two thirds of the total amount of the polymer) being incorporated into the pure soap and the other part being added to the soap slices in the soap mixer. To reduce the tendency to crack when the latter addition is made in the soap mixer, it is desirable to add the polymer in the form of very finely ground material (such as a material of which 98% passes through a No. 100 sieve according to the US Sieve Series Standard and to carefully distribute the powdered polymer on the surfaces of the slices or flakes in the soap blender before the addition of the other ingredients, such as the pigment.When a significant part of the total amount of polymer is incorporated in the pure soap, the soap becomes less sticky during the addition of the rest of the polymer in the soap blender and According to one embodiment of the invention, the sodium soap is a mixture of about equal parts of tallow and coconut oil soaps.The greasing acids according to a suitable embodiment comprise a mixture of about equal parts of stearic and coconut fatty acids.

In the preparation of the composition, it is convenient to use a mixture of specified components containing 0.5 - 5 parts of water per part of poly- (ethylene oxide), and in a preferred embodiment a mixture of specified components containing about 4-8 parts is used. of said superfat fatty acids and about 1 -12 parts water per part poly- (ethylene oxide).

It is to be understood that the above detailed description is provided only to illustrate the invention and that variations may be made therein without departing from the spirit of the invention.

Claims (7)

7807559-5 15 P a t e n t k r a v Composition for the preparation of toilet soap in piece form, characterized in that it essentially comprises sodium soap of higher fatty acids having 8 to 20 carbon atoms, 6 to 12% of higher fat fatty acids having 8 to 20 carbon atoms, 1 - 4% poly- (ethylene oxide), which has a molecular weight in the range from 100,000 to 5,000,000, and 5 - 18% water. Toilet soap composition according to claim 1, characterized in that said molecular weight is 300,000 to 600,000 and that the proportion of poly (ethylene oxide) is 1.5 - 3%. Toilet soap composition according to claim 1 or 2, characterized in that said sodium soap is a mixture of tallow and coconut oil soaps in a ratio of 1: 2 - 2: 1. Toilet soap composition according to any one of claims 1 - 3, characterized in that said fatty acids comprise a mixture of stearic and coconut fatty acids in a ratio of 2: 1 - 1: 2. Process for the preparation of a composition for the production of toilet soap in one piece according to any one of claims 1 to 4, characterized in that a molten mixture of polyethylene oxide having a molecular weight in the range 100,000 to 5,000,000 in an amount of 1 4%, and overfat higher fatty acids with 8 - 20 carbon atoms in an amount of 6 - 12%, it is achieved that this mixture is mixed with pure soap containing said sodium soap and about 27 - 32% moisture, and that the resulting mixture is subjected to drying conditions. 7807559-5 16 6. A process according to claim 5, characterized in that said mixture contains 2 - 20 parts of said superfat fatty acids per part of poly- (ethylene oxide). 7. A process according to claim 5 or 6, characterized in that said mixture contains a smaller proportion of dispersed water which is sufficient to reduce the viscosity of said mixture.