TECHNICAL FIELD
The present invention relates to the process of making low-density soap formulation and the method of its preparation thereof.
BACKGROUND
When soap is used for washing purposes, the soap becomes slippery and can be easily dropped from the hands of the user and gets sunk to the bottom of the water reservoir. Retrieving the soap from the bottom of the bathtub or other water body is often difficult, inconvenient and time-consuming. Although low-density soaps prepared by entrapment of small air bubbles are available, they are less dense and more prone to quick dissolution in the water, thereby depleting rapidly.
Floating soaps currently available are produced by introducing a hollow cavity inside, or whipping air into the liquids. This makes the soap have weak consistency, weak structural integrity and also dissolves quickly. Due to its higher density than water, the soap slips and get sunk in water, which leads to the undue loss of the soap.
There are many ways of producing a floating soap e.g. by injecting air or specific gas into liquid or semi solid soap mass and allowing solidification. Prior art search reveals various patents related to floating soap and its process of preparation thereof.
EP0713526 discloses an aerate/honeycombed soap product that is self-skinning and of a density less than that of water formed from the application of microwaves to a soap piece produced by a conventional soap-making process.
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US5972860discloses a framed soap composition comprising:
(a) 20 to 50% by weight of a fatty acid soap;
(b) 1-15% by weight of a nonionic surfactant; and
(c) 0.1-5% by weight of an inorganic salt.
A framed soap composition incorporated with air bubbles is produced by melting a mixture containing these components while heating the mixture in the presence of water, subjecting the resultant molten material to aeration treatment to incorporate air bubbles, and pouring the resultant molten material incorporated with air bubbles, into a frame followed by cooling to harden the molten material.
WO 96/25480 describes a buoyant soap bar produced from raw soap by grinding, adding water, kneading, heating, cooling and optionally shaping or moulding.
WO 99/66022 aims at providing a method for producing floating soap and a mixing system enabling production of different floating soaps in a continuous method using charges of any given size.
US 2295594 and US 3835580 describes the making of "ivory soap" by whipping air into liquid which is poured into a mould which is altowed to solidify into a buoyant, rectangular or cubic product. US 3835058 further exposes the possibility of injecting compatible gas which is not air in to liquid / semi solid soap to make it float.
US 5194172 discloses an aerated and/or freezer soap bar composition, which contains a substantial amount of sucrose, has improved processability, improved physical and/or improved skin mildness characteristics.
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US 52X9487 discloses aerated soap bar compositions that contain a limited amount of free fatty acid and salt having improved processing and physical characteristics if the fatty acid soap comprises only a limited amount of trans fatty acids. Superior wet crack and bar feel grades are found, as opposed to similar bars having higher trans fatty acid content. Higher amounts of fatty acid require less inorganic salt for proper viscosity of the crutcher mix.
US 6770606, discloses an aerated, ultra low-density cast-dehydrated syndet detergent bars for use in personal wash, fabric wash and hard surface cleaning. A process is also provided for preparing aerated, ultra low-density cast-dehydrated detergent bar wherein the air is entrained in the bars after rigidification and shaping the product.
US 5602088 and 5895780 discloses the art of making the overall physical density of the soap having the hollow recess by adding 98% of soap base, 1% fragrance and 1% of colour and extruded into soap billet which has the hollow concavity. The hollow centre may remain empty or filled with substances having light density water and sealed.
The prior art which provide a process comprising whipping air or other gases in to liquid gives weak consistency, structural weakness and quick dissolving of soap than the conventional soaps for regular use and the process of injecting compatible gas into liquid is also an expensive process.
Further, the art of making the overall physical density of soap through extruding the soap into hollow cavity billet and sealing may cause the soap to drown once the sealing gets opened.
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OBJECT AND SUMMARY
The principal object of the present invention is to provide a floating soap with low density.
Another object of the present invention is to provide a floating soap which can be produced without an aeration step.
Still another object of the present invention is to provide a floating soap which is useful for its integrity and is less prone to get sunk in water.
Yet another object of the present invention is to provide a floating soap which can be produced easily.
Still another object of the present invention is to provide a floating soap which can be made in various forms and shapes.
Yet another object of the present invention is to provide a floating soap which dissolves at slower rate.
Still another object of the present invention is to provide a floating soap which is cost-effective.
Yet another object of the present invention is to provide a floating soap which is less acidic as compared to conventional soap.
Still another object of the present invention is to provide a floating soap which has reduced less slippery.
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Yet another object of the present invention is to provide a floating soap which retains its oily nature.
Still another object of the present invention is to provide a floating soap which also has a provision of mixing various additives to get desired effects.
Yet another object of the present invention is to provide a floating soap in which plants / plant extracts can be added during the preparation.
The present invention relates to a floating soap formulation comprising:
a. 5 % to 15% of caustic lye;
b. 35% - 45% of coconut/vegetable oil;
c. 8% - 12% of fatty acid;
d. 8% -12% by weight of glycerin;
e. 10%-15% fatty acid; and
f. 20% - 30% of water.
The present invention further relates to a process for the preparation of a floating soap formulation comprising the steps of:
a. mixing 5 % to 15% by weight of caustic Lye, 20% - 30% by weight
of water, 35% - 45% by weight of coconut oil/vegetable oil, 8% -
12% by weight of fatty acid; 8-12% by weight of glycerin and
sodium chloride.
b. adding colour and fragrance to said mixture and agitating the same
at 100-130 rpm for 25-35 min; and
c. cooling the mixture of step b. overnight.
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DETAILED DESCRIPTION
The present invention provides a floating soap formulation that has less density than water and other liquids.
The present invention relates to a formulation of floating soap, prepared using sodium hydroxide (caustic soda) and coconut/vegetable oil. The modifications are made to make the soap density lesser than water or other liquids of like density, by interfering with the normal process of saponification.
The proposed innovation has the unique process of making overall physical density lesser than the water by adding vegetable oil i.e. fat which makes the soap to float without any practical disturbances.
The floating soap formulation comprises:
b. 5 % to 15% of caustic lye;
c. 20% - 30% of water;
d. 35% - 45% of coconut/vegetable oil;
e. 8% -12% of stearic acid;
f. 8% to about 12% by weight glycerin; and
g. 10%-15% fatty acid.
The floating soap formulation can be prepared as follows:
1. Mixing of caustic Lye, water, coconut oil, stearic acid and other fatty acids, in required proportions.
2. Agitation by addition of colour and fragrance at 120 rpm for 30 min.
3. Allowing natural cooling over-night.
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This process makes the density of the components lighter than water and makes the soap float on water. The resulting formulation acquires the following physical characteristics
(a) density of 0.878;
(b) TFM 73%;
(c) Foaming stability 0.1 cms; and
(d) Foaming power 0.2 cms.
The composition is comparatively easy to manufacture and is cheaper than the available products
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