CLIAMS:NONE ,TagSPECI:Field of invention
The present invention relates to a composition for improved surface finish of casted syndet base bathing bar. More particularly, the present invention relates to specific ratio of inorganic: organic structurants. The present invention further provides a process for producing improved surface finish casted syndet base bathing bar.
Background and prior art
Synthetic surfactant-based personal cleansing bars have attracted much interest because they can be selected to be milder to the skin than soap-based products. This mildness however, comes with negative to both the manufacturer and the consumer. The bar soap manufacturer experiences difficulties in the processibility while the consumer experiences the properties of poor lather, messy smear, bar softness and high wear rates.
WO2011/080101 teaches personal washing bar which includes a continuous phase which is substantially free of a water soluble detergent builder, the continuous phase comprising:
a. 20% to 50%, preferably 25% to 40%, more preferably 30% to 37% fatty acid soap, wherein the fatty acid soap comprises less than 39% of an unsaturated fatty acid soap by weight of the fatty acid soap;
b. A structuring system comprising:
i) From 10% to 45%, preferably 20% to 40% by weight of the of the continuous phase of a polysaccharide structurants selected from the group consisting of starch, cellulose and a combination thereof,
ii) From 6.0% to 30%, preferably 10% to 20%, by weight of continuous phase of a polyol selected from the group consisting of glycerol, sorbitol and their mixtures, and
iii) 0 to 15%, preferably 4% to 10% by weight of continuous phase of a water insoluble particulate material;
c. 0.5% to less than 3%, preferably 0.5% to less than 2.5%, of an anticracking agent selected from the group consisting of carboxymethyl cellulose, polyacrylates and mixtures thereof;
d. From 10% to 20%, preferably 15% to 18% water

wherein the 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. Conveniently the bar has a Cracking Index of 1 or less.

US 6849585 relates to soap/free fatty acid bars in which high amounts of free fatty acid (i.e., greater than 35%, preferably greater than 40% and ratio of FFA to soap greater than 1:1) and low levels of synthetic may be used. In the bar, the free fatty acid is believed to form a complex which is believed to act as a structurant, thereby allowing less use of synthetic surfactant. The bar should require less synthetic surfactant. Total amount of unsaturated material in soap and fatty acid should be no higher than 15%. Specifically, compositions of the invention comprise:
(1) at least about 65% by wt., preferably at least 66%, more preferably at least 68%, more preferably at least 70% mixture of fatty acid soap and free fatty acid wherein at least 35%, preferably at least 37%, more preferably at least 40% by wt. more preferably more than 40% by weight of bar is free fatty acid and wherein said fatty acid soap in the bar is preferably although not necessarily produced when FFA mixes with less than 50 mol % caustic (Also preferably the ratio of FFA to soap is at least 1:1 and preferably greater than 1:1);
(2) less than 25%, preferably less than 24%, more preferably less than 20% non-soap synthetic surfactant (preferably amount of the FFA is greater than level of synthetic);
(3) less than 15%, preferably less than 14% (e.g., 2-14%) water; wherein said bar has lather of at least 50 ml, measured by BLAM, as referenced test;
wherein said bar is preferably prepared by an extrusion process; and
wherein the hardness of the extrusion bar is at least 90 kPa, preferably at least 100 kPa, as measured by cheese wire method.
However, the present invention provides a composition for improving surface finish of casted syndet bar using unique ratio of inorganic:organic structurants. The present invention relates to syndet rich personal washing bar. Further the present invention provides a process for producing improving surface finish of casted syndet bar.
Object of the invention
It is object of the present invention to overcome the disadvantages of the prior arts.
It is another object of the present invention to provide a composition for improved surface finish of casted syndet bar.
It is another object of the present invention to provide a process for producing improved surface finish of casted syndet bar.
It is yet another object of the present invention to provide a composition for producing improved surface finish of casted syndet bar having a specific ratio of inorganic:organic structurants.
It is yet another object of the present invention to provide a process for producing improved surface finish of casted syndet bar having a specific ratio of inorganic:organic structurants.
Description of the invention
The present invention relates to a process for improving surface finish of casted syndet bar by using unique combination of structurants, e.g., organic or natural structurants such as starches (like maize, tapioca, rice etc), inorganic natural structurants (kaolin, bentonite, fuller earth etc), inorganic synthetic structurants such as sodium/magnesium/calcium aluminium silicate, silica etc. The essential feature of the present invention resides in the ratio of inorganic:organic ratio (1:4 to 1:1). The said ratio is required to achieve the following results:
- No or reduce bubble formation at the surface of bar, hence improve bar aesthetics.
- Balance moisture content to remove any cracking on surface
- Smooth and even surface
- Improved bar glide during application

The process for the preparation of the syndet bar of the present invention comprises the steps of:
I. Mixing all fatty acids (4-12% w/w) , polymers (1-7% w/w) , waxes (5-16% w/w) , oil (0.5-3% w/w), emulsifier(1-10% w/w) in mixer at 65-750C
II. Post melting and mixing for sufficient time (20-30mins), add soap at 85-900C
III. Post soap melting add pH regulator (citric acid-0.2 -1.5% w/w) followed by surfactants (SCI 65%-40-55% w/w). Maintain temperature between 90-950C
IV. Addition of other additives like TiO2 (0.1-0.4%w/w), EDTA (0.025-0.1%w/w), on complete mixing of soap and surfactants
V. adding structurant (organic (1-8 %w/w)/Inorganic(2-8%w/w)) at high mixing speed followed by homogenization.
VI. add emollients(0.5-2%w/w) once all the powders are mixed into the mass properly.
VII. Mixing till achieve homogenous flow able mass, then cast into desired moulds for solidification

Preferred emulsifier used are AOS, SLES [1EO, 2EO], preferred pH regulator used are citiric acid, lactic acid, preferred surfactant used are SCI 65%, CAPB, preferred inorganic structurant used are aluminum silicate, sodium silicate and preferred organic structurant used is maize, preferred emollients used are glycerine, PEG-400.
Further, the formulation of the present invention can be made and casted at temperature less than 1000C in the mixing system which is crutcher or any planetary mixer having homogenizer. Moreover, the composition of the present invention does not require any plodding to achieve bar.
The present invention is now described by way of non-limiting illustrating examples.
Example 1
4-10 wt% of C16 to C18 fatty acid in the ratio of 1:1, waxes (11%), oil (4%) and emulsifier (5%) are mixed at 65°C for 25 mins. To this mixture 15 wt% soap is added at a temperature of 85°C. After soap is melted, pH regulator is added followed by 43wt% of surfactants and maintained at a temperature of 95°C. Other additives like TiO2, EDTA are added on complete mixing of soap and surfactants. To this mixture 4wt% inorganic and 4wt% organic structurants is added at high mixing speed followed by homogenization. 1wt% of emollients are added once all the components are mixed into the mass. The components are mixed until a homogeneous flowable mass is achieved. The mixture obtained is then cast into desirable moulds for solidification.

Example 1: (Working example)
S.No. Ingredient Wt / wt %
1 Surfactant 40-65
2 Free Fatty Acid/ plasticizer 4-12
3 Emulsifiers 0.5-10%
4 Polymer 1-7
5 Soap 10-20
6 Binders 0.5-4
7 Oil 0-5
8 Emollient 0-2
9 Preservatives 0.01-0.5
10 Color / Fragrance / Emotive 0-1.5
11 pH Regulator 0.5-2
12 Wax 2-20
13 Minerals 0-5
14 Organic Structurant 1-10
15 Inorganic Structurant 1-8

Example 2: (best working example)
S.No. Ingredient Wt / wt %
1 Surfactant 40-46
2 Free Fatty Acid/ plasticizer 4-8
3 Emulsifiers 2-5
4 Polymer 2-5
5 Soap 10-16
6 Binders 0.5-4
7 Oil 0-2
8 Emollient 1-2
9 Preservatives 0.01-0.5
10 Color / Fragrance / Emotive 0-1.5
11 pH Regulator 0.5-2
12 Wax 13-15
13 Minerals 0-5
14 Organic Structurant 4-8
15 Inorganic Structurant 2-6

Example 3: (Non working example)
S.No. Ingredient Wt / wt %
1 Surfactant 25-35
2 Free Fatty Acid/ plasticizer 4-8
3 Emulsifiers 0.5-1
4 Polymer 2-5
5 Soap 30-45
6 Binders 0.5-4
7 Oil 5-8
8 Emollient 1-2
9 Preservatives 0.01-0.5
10 Color / Fragrance / Emotive 0-1.5
11 pH Regulator 0.5-2
12 Wax 13-15
13 Minerals 0-5
14 Organic Structurant 1-2
15 Inorganic Structurant 0-0.2

According to table 3, it is demonstrated that the desired bar smoothness is not achieved outside the specific ratio of inorganic:organic structurants.