CLIAMS:1. A low total fatty matter (TFM) soap bar comprising:
f) between 40% and 55% of TFM;
g) between 22% and 27% weight by weight of TFM of at least one water insoluble inorganic particle;
h) between 1% and 9% of binders wherein at least two binders are silica and lauric acid;
i) between 1% and 10% of at least one polyol;
j) between 0.01% and 0.1% of at least one polyethylene oxide resin; and

wherein the weight ratio of polyol to lauric acid is between 2:1 and 5:1 and the weight ratio of silica to polyethylene oxide resin is between 3:0.1 to 15:0.1 and the weight ratio of lauric acid to water insoluble inorganic particulates is between 0.2:3 and . 1.2.

2. The soap bar as claimed in claim 1, wherein the weight ratio of polyol to lauric acid is 4:1.

3. The soap bar as claimed in claim 1, wherein the weight ratio of silica to polyethylene oxide resin is 3:0.1.

4. The soap bar as claimed in claim 1, wherein the weight ratio of lauric acid to water insoluble inorganic particulates is 1:5.

5. The soap bar as claimed in claim 1, wherein the polyethylene oxide is within the range of 0.1% to 2% of the total polyols.

6. The soap bar as claimed in claim 1, wherein binder is selected from lauric acid, myristic acid, C8-C10 fatty acids, hydrated silica, silica and combination thereof.

7. The soap bar as claimed in claim 1, wherein water insoluble inorganic particulates are selected from talc, clays, phosphates, aluminates, silicates, dolomites and combination thereof.

8. The soap bar as claimed in claim 1, wherein polyols are selected from glycerine, propylene glycol, sorbitol, low molecular weight PEG and combinations thereof.

9. The soap bar as claimed in any of the preceding claims, wherein the soap bar further comprises surfactant and water.

10. The soap bar as claimed in claim 9, wherein surfactants are selected from anionic surfactants.
,TagSPECI:FIELD OF INVENTION

The present invention relates to the high filler low TFM soap with superior lather and high moisture retention.

BACKGROUND OF THE INVENTION AND PRIOR ART
Traditional soap bars are made from soap noodles, with 70 wt% or more of total fatty material (TFM), 10-14 wt% water, and include other additives. These bars are mainly produced by mixing the soap noodles with other additives, followed by steps of milling, extruding and stamping. Soap bars with such high amounts of TFM provide sufficient cleaning and good bar integrity, however during storage and use, it is to be cost extensive to manufacture, mainly due to the high cost associated with the raw material. It is known that that high amounts of TFM is not a requisite for cleaning purposes. Sufficient cleaning can be achieved even with lower amounts of TFM, however such low amounts of TFM often result in negatively impacting other user desirable properties like bar integrity, in-use and post wash performance, softness and smoothness.
Usually high amounts of fillers are potential alternatives to make make low TFM soap bars. However, the addition of large amounts of water or fillers affects the cleansing and sensory feel of the soap as well as the processing conditions. Low TFM soaps having high amount of fillers like talc, clays, oxides, silicates, Ca-Mg carbonates and dolomites often have the followingproblems:
· High amount of inorganic fillers in soap reduces the plasticity of the mass and it will ultimately lead to development of cracks on both the surfaces of the soap tablet.
· High fillers will lead to inferior in-use and post use properties like poor surface smoothness of the bar during use (grainy or powdery feel), poor bar glide on skin & these properties lead to dry skin post application of soap.
· Moisture content of these soaps, in general is very less and inadequate to maintain the binding efficiency in the presence of high amount of fillers this leads to very dry soap with poor aesthetics (very hard soap during use)
WO2011080101discloses and describes low TFM personal washing bar comprising 20% to 50% fatty acid soap; a structuring system comprising of 10% to 45% polysaccharides; 6.0% to 30%polyols; 0 to 15 % continuous phase of awater insoluble particulate material; 0.5% to less than 3% an anticracking agent. However use of polysaccharides in structuring system from 10-45% and anticraking agent in formulation thereby allowing maximum fillers upto 0 -15 % of continuous phase of fillers.

WO2010089269 discloses and describes soap bars with polyethylene oxide resins and polyol, silica, lauric acid, water insoluble particles. It particularly describes a low TFM extruded personal soap bar having a continuous phase comprising: a. 20% to less than 45% fatty acid soap in which the fatty acid soap comprises at least 30% saturated fatty acid soaps based on the total weight of the soap and wherein the fatty acid soap has a ratio ROL, defined as the total weight of oleic fatty acids soaps divided by the total weight of the lauric fatty acid soaps which satisfies Eq (1); ROL = (-0.00063(TS2)+0.297(TS)-1.95) ± 15% (1) where TS is the weight % fatty acid soap in the composition; b. a structuring system comprising: i) from 10% to 40% by weight of continuous phase of a polysaccharide structurant selected from the group consisting of starch, cellulose and a mixture thereof ii) from 8.0% to 30% by weight of continuous phase of a polyol selected from the group consisting of glycerol, sorbitol and their mixtures, and iii) 0 to 15% by weight of continuous phase of water insoluble particulate material, wherein the weight of polysaccharide structurant divided by the weight of polyol, designated Rsp, is in the range from 0.3 to 5.0 and wherein continuous phase is an extrudable mass having a penetrometer hardness of 3 to 8 kg and a yield stress of 350 to 2000 kPa measured at a temperature of 40°C.

CN101554357 discloses and describes soap bars having polyethylene oxide resins, polyol, water-insoluble particles (0-10%), silica, lauric acid. According to CN’357 compositions containing starch - structured system polyol extruded soap bar is provided including: a) 45% -60% of a fatty acid soap; b) 0.3% - less than 1.5% of one or more of adding a soluble salt of a monovalent cation; c ) is less than 5.0% of the fatty acids; and d) a structured system comprising: i) 5.0% -14% of a polyol selected from glycerol, sorbitol, and mixtures thereof, ii) 6% -25% of the starch, and iii) 0-10% of a water-insoluble particles, wherein the polyol, starch and inorganic particles by weight of the sum of the weights which share at least about 20% but not more than 30%; section and wherein the composition is extrudable material, in 40°C temperature measurement between a 350-2000kPa yield stress.

While use of lower amount of filler leads to increase in amount of soap for the processability thus contributing for the overall TFM content and increases the cost of final product.

However, prior art do not teach soap bars with reduced crack which are commercially processable and feasible when fillers are used at higher dosage without use of polysaccharide structuring agent like starch, cellulose or anticracking agents. Use of polysaccharides leads to very dry mass due to absorption of high amount of water apart from causing poor binding while processing of soap bar.

Therefore, there continues to be a need for improved soap bars with an increased amount of water or fillers wherein the soap bars are able to provide effective cleansing property with lowered TFM and renders the use of structuring agents, like polysaccharides, and anticracking agents unnecessary.

Accordingly, the present inventors have provided a low TFM soap bar formulation without polysaccharides and anti-cracking agents.

OBJECTS OF THE INVENTION

It is an object of the present invention to overcome the disadvantages of existing soap bars containing low amounts of TFM.

It is another object of the present invention to provide soap bars containing low TFM and high amounts of fillers while exhibiting improved in-use and post use properties.

It is a further object of the present invention to provide low TFM soap bars without structuring agents, like polysaccharides, or anti-cracking agents.

It is yet another object of the present invention to provide low TFM soap bars with superior aesthetics and in-use properties like superior lather, retention of product moisture, excellent bar glide properties during application and no skin dryness post application of the soap.

SUMMARY OF THE INVENTION
In one aspect the present invention provides a low total fatty matter (TFM) soap bar comprising:
a) between 40% and 55% of TFM;
b) between 22% and 27% weight by weight of TFM of at least one water insoluble inorganic particle;
c) between 1% and 9% of binders wherein at least two binders are silica and lauric acid;
d) between 1% and 10% of at least one polyol;
e) between 0.01% and 0.1% of at least one polyethylene oxide resin; and

wherein the weight ratio of polyol to lauric acid is between 2:1 and 5:1 and the weight ratio of silica to polyethylene oxide resin is between 3:0.1 to 15:0.1 and the weight ratio of lauric acid to water insoluble inorganic particulates is between 0.2:3 and . 1.2.

BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS

FIG. 1 illustrates the side view of soap without cracks
FIG. 2 illustrates the top view of soap without cracks
FIG. 3 illustrates the side view of cracked soap
FIG. 4 illustrates the top view of cracked soap

DETAILED DESCRIPTION OF THE INVENTION

The present invention relates to a low TFM soap with superior bar aesthetics and in-use properties like superior lather, retention of product moisture, excellent bar glide properties during application and no skin dryness post application of the soap which comprises water insoluble particulate matter, referred as fillers, greater than 22% of the continuous phase along with other raw materials.

In particular, it provides a soap bar with lower TFM and higher amount of water insoluble particulate matter referred as fillers more than 15 % of the total composition to achieve desired benefits in a cost effective way.

The present invention provides a low TFM soap bar comprising total fatty matter in an amount between 40% and 55% and fillers in form of water insoluble inorganic particles in an amount ranging between 22% and 27% of the continuous phase by weight said continuous phase being the total fatty matter present in the formulation using conventional soap manufacturing line assembly.

The present invention describes soap bars comprising low TFM and higher amount of fillers with reduced crack and being commercially processable and feasible when fillers are used at higher dosage without use of polysaccharide structuring agents like starch, cellulose or anticracking agents. Further the soap bar is devoid of anti-cracking agent or structuring agents like starch or cellulose, which were believed and known to be essential for smooth and easy manufacturing of soap bar. Use of polysaccharides leads to very dry mass due to absorption of high amount of water and poor binding while processing. Besides bar has poor aesthetics and develops cracks during use.

In the present invention, surfactants can be selected from Alfa Olefin Sulfonate, SLES 70%. The anionic surfactant can be selected from an aliphatic sulfonate such as a primary alkane (e.g., C8-C22) sulfonate, primary alkane (e.g., C8-C22) disulfonate, C8-C22 alkene sulfonate, C8-C22 hydroxyalkanesulfonate or alkylglyceryl either sulfonate (AGS); or an aromatic sulfonate such as alkyl benzene sulfonate and used in an amount ranging from 4% to 8% by weight of the total composition. Humectants can be selected from polyols including glycerin, sorbitol, propylene glycol, low Mw PEG, and the like or mixtures thereof and used in an amount ranging from 2.5% to 6% by weight of the total composition. Binders can be selected from lauric acid, C8-C10 fatty acids, myristic acid, silica, and used in an amount ranging from 18% to 28% by weight of the total composition.

The present inventors have surprisingly found that a unique combination of high molecular weight polyethylene oxide and the binder particularly silica maintains bar slipperiness property of the low TFM soap bars. The weight ratio of high molecular weight silica to polyethylene oxide ranges between 3: 0.1 and 15: 0.1. Use of silica and polyethylene oxide at these ratios also result in retention of higher amount of product moisture in the finished soap.

“Water insoluble inorganic particles” are selected from comprising of talc, clays, phosphates, aluminates, silicates, dolomites and the like and mixtures thereof.

“High molecular weight” polyethylene oxide resins means resins having molecular weight between 100000 and 4500000. Such polyethylene oxide resins include polyox WSR 301, Polyox WSR 3000N.

The high molecular weight polyethylene oxide resin is dispersed homogeneously in aqueous media in the soap amalgamation step along with polyols. The amount of such resin is between 0.005 and 0.04% w/w in the final product.

The present inventors surprisingly found that when the amount of polyethylene oxide is within the range of 0.1% to 2% of the total polyols in the low TFM soap bar, it provides improved skin slipperiness & skin smoothness post application of the soap bar. The weight ratio of polyol to lauric acid between 2:1 and 5:1 also results in surprisingly superior bar properties.

The inventors further found that when the ratio is between lauric to the water insoluble particle ranges between 0.2:3 and1:2, it leads to better binding and plasticity for superior surface finish.
The present invention also overcomes issues of poor surface finish, cracking of soap bar, inferior in-use and post wash performance of the soap. It further has improved moisture retention capacity of the soap which in turn helps to maintain the soap softness property & density profile.

The examples are intended to be purely exemplary of the invention and should therefore not be considered to limit the invention in any way. Efforts have been make to ensure accuracy with respect to numbers used, but some experimental errors and deviations should be accounted for.

Examples

These examples illustrates an opaque soap formulation containing water insoluble matter more than 22% of the continuous phase with a unique ratio of polyoxides: polyols, having superior in-use properties and good bar aesthetics.

Example 1: Preparation of the low TFM

The soap bar of the present invention was prepared according to the below method
Add the 53gm of soap noodles with 15gm water to Sigma mixer and crush the noodles to powder form. –The composition of the soap noodles used can be 85:15 or 80:20 blend of fatty acids
· Add 0.48 gm of salt and 0.5 gm of soda ash and mix the mass for 2 min
· To the homogenous mass add the 6 gm of surfactants (Alfa Olefin Sulfonate,SLES 70%) and mix for 2 min
· Add 5 gm of the Polyols and mix for 2 min
· Add all the filler step wise (as the quantity of the material is high) and mix for 4 min
· Dose 0.02 gm PolyOX pre-mix(PolyOX dispersed homogeneously in aqueous medium) and allow the mass to mix for 3 min
· Add 1 gm of fragrance and mix for 1 min

The working range of the formulation is tabulated below.
Table 1
Materials w/w% Range Function
Soap 40-55 Surfactant
Lauric Acid 2-4 Binder
Alfa Olefin Sulfonate 2-5 Surfactant
SLES 70% 1-5 Surfactant
Hydrated Silica 1-5 Binder
PolyOX WSR 301 0.01-0.1 Plasticizer
Talc 9 -22 Filler
Glycerin 1-10 Humectant
Sorbitol 1-4 Humectant
Soda Ash 0.3-1
Salt 0.3-1
Water 8 - 20 Binder
Fragrance 0.8-1.5

Example 1(a)
A soap bar was prepared having the ingredients tabulated in Table 2 below

Materials w/w% Function
Soap 55 Surfactant
Lauric Acid 2.5 Binder
Alfa Olefin Sulfonate 2.5 Surfactant
SLES 70% 3.5 Surfactant
Hydrated Silica 3 Binder
PolyOX WSR 301 0.02 Plasticizer
Talc 9.5 Filler
Glycerin 3 Humectant
Sorbitol 2 Humectant
Soda Ash 0.5
Salt 0.48
Water 17 Binder
Fragrance 1

In this example a soap bar was prepared according to the method of example 1 having the ingredients as specified in table 2. As seen, the ratio of silica to polyethylene oxide is 15:0.1, the ratio of polyol to lauric acid is 2:1 and the ratio of lauric acid to water insoluble particle is 1:3.8. The polyethylene oxide ratio is within 0.1% to 2% of total polyols. The resultant soap bar was stable without any cracks and had good bar aesthetics with a lather volume of >300 ml in kitchen blender method.

Example 1(b)
A soap bar was prepared having the ingredients tabulated in Table 3 below

Materials w/w% Function
Soap 53 Surfactant
Lauric Acid 2.5 Binder
Alfa Olefin Sulfonate 2.5 Surfactant
SLES 70% 3.5 Surfactant
Hydrated Silica 3 Binder
PolyOX WSR 301 0.02 Plasticizer
Talc 12.5 Filler
Glycerin 3 Humectant
Sorbitol 2 Humectant
Soda Ash 0.5
Salt 0.48
Water 16 Binder
Fragrance 1

In this example a soap bar was prepared according to the method of example 1 having the ingredients as specified in table 3. As seen, the ratio of silica to polyethylene oxide is 15:0.1, the ratio of polyol to lauric acid is 2:1 and the ratio of lauric acid to water insoluble particle is 1:5. The resultant soap bar was stable without any cracks and had good bar aesthetics with a lather volume of >300 ml in kitchen blender method.

Figures 1 and 2 illustrate the bars of examples 1 and 2 that have better superior surface finish and do not develop cracks.

Example 1(c): Formulation with polysaccharide
A soap bar was prepared having the ingredients tabulated in Table 4 below

Materials w/w% Function
Soap 53 Surfactant
Lauric Acid 2.5 Binder
Alfa Olefin Sulfonate 3 Surfactant
SLES 70% 3 Surfactant
Hydrated Silica 2 Binder
Starch 14 Filler
Glycerin 5 Humectant
Sorbitol 3 Humectant
Soda Ash 0.5 Builder
Salt 0.5 Filler
Water 10 Binder
Fragrance 1

In this example a soap bar was prepared according to the method of example 1 having the ingredients as specified in table 4. The resultant soap bar was not stable, dry and developed cracks on both the soap surfaces, which rendered it aesthetically unappealing. The bar had very less surface smoothness during use.
Figures 3 and 4 illustrate these bars.

Example 1(d)
A soap bar was prepared having the ingredients tabulated in Table 5 below

Materials w/w% Function
Soap 48.75 Surfactant
Lauric Acid 1.25 Binder
Alfa Olefin Sulfonate 3 Surfactant
SELS 70% 3 Surfactant
Hydrated Silica 2 Binder
Talc 22 Filler
Glycerin 5 Humectant
Sorbitol 3 Humectant
Soda Ash 0.5 Builder
Salt 0.5 Filler
Water 10 Binder
Fragrance 1

In this example a soap bar was prepared according to the method of example 1 having the ingredients as specified in table 5. The resultant soap bar was not stable, dry and it developed cracks, which also rendered it aesthetically unappealing. Due to absence of plasticizer and high amount of fillers in the bar, it had a drag feel during use with less plasticity.

Example 1(e)
A soap bar was prepared having the ingredients tabulated in Table 6.
Materials w/w% Function
Soap 54.29 Surfactant
Lauric Acid 6 Binder
Alfa Olefin Sulfonate 3 Surfactant
SLES 70% 7 Surfactant
Hydrated Silica 0.2 Binder
PolyOX WSR 301 0.01 Plasticizer
Talc 5 Filler
Glycerin 2 Humectant
Sorbitol 2 Humectant
Soda Ash 0.5
Salt 0.5
Water 18.5 Binder
Fragrance 1

In this example a soap bar was prepared according to the method of example 1 having the ingredients as specified in table 6. As seen the ratio of silica to polyethylene oxide is 2:0.1, the ratio of polyol to lauric acid is 0.66:1 and the ratio of lauric acid to water insoluble particle is 1:0.83, which are lesser than the inventive ratios. The resultant soap bar had poor processability along with inferior bar surface finish and aesthetics. Also, the bar was not stable and became very soft during use.

Example 1(f)
A soap bar was prepared having the ingredients tabulated in Table 7 below
Materials w/w% Function
Soap 48.75 Surfactant
Lauric Acid 1.25 Binder
Alfa Olefin Sulfonate 3 Surfactant
SLES 70% 3 Surfactant
Hydrated Silica 2 Binder
PolyOX WSR 301 0.01 Plasticizer
Talc 22 Filler
Glycerin 5 Humectant
Sorbitol 3 Humectant
Soda Ash 0.5
Salt 0.49
Water 10 Binder
Fragrance 1

In this example a soap bar was prepared according to the method of example 1 having the ingredients as specified in table 7. As seen the ratio of silica to polyethylene oxide is 20:0.1, the ratio of polyol to lauric acid is 6.4:1 and the ratio of lauric acid to water insoluble particle is 1:17.6, which are higher than the inventive ratios. The resultant soap bar was not stable and developed cracks, which rendered it aesthetically unappealing. The bar also had a drag feel during use.

Comparison of soap bar properties
Table 8
Formulation Physical bar property Bar plasticity Bar Surface finish Processability
Example 1(c) Crack Poor Poor Difficult( Less binding)
Example 1(a) No Crack Good Good Good