Presented by Mahesh A. Kesalkar

1. RHEOLOGICAL ADDITIVES IN COSMETICS
PRESENTED BY
MAHESH A. KESALKAR
{PHARMACEUTICS}
Institute of Pharmaceutical Education And Research, Borgaon
(Meghe), Wardha
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2. CONTENT
 Introduction
 Cosmetics And Rheology
 Classification of Rheological additives
 Applications
 References
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3. Introduction
 Todays successful cosmetics products need the right rheological properties and the
correct choice of rheological additives enhances the product in production, storage
stability and application.
 Rheological additives for aqueous and non-aqueous formulations are valuable and
proven tools for you to use,
 Personal care
 Skin care
 Sun care
 Decorative cosmetics
 All can benefit from rheological additives.
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4. Cosmetics And Rheology
 Rheology is the science of flow.
 Every time a lotion is poured, a cream squeezed from a tube or a lipstick
applied, rheology is involved.
 Even when products are at rest, it plays an important part in controlling stability
and suspension.
 Understanding a formulations rheological needs enables you to create the best
possible products.
 The rheology of a system is described in terms of its viscocity. Viscocity is the
resistance to flow and defined as:
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5.  Shear stress is the force per unit area applied and shear rate is the resulting velocity
gradient.
 Cosmetics experience shear rates varying from 0.001 s-1, from gravitational forces to
over 20,000 s-1, when a cream is spread or an aerosol antiperspirant sprayed.
 The way and the viscocity, regardless of shear rate greatly influences the overall produc
stability and performance.
 A material which maintains a constant viscocity, regardless of shear rate, has Newtonian
flow.
 Dilatant flow is a form where viscocity increases with shear.
5VISCOCITY= shear stress / shear rate

6.  Pseudoplastic flow, also known as shear thinning behaviour, and topical of many
commercial systems, is when viscocity decreases with increasing shear rate.
 Viscocity can be temperature dependent, correct choice of rheological additive
allows you to create the ideal flow characteristics and also achieve thermostable
rheology.
S
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7. Classification of rheological additives
 A)Aqueous phase additives
1) Rheoluxe associate thickeners
2) Hectorite
3) Bentone hydrophilic clays
 B)Non-aqueous phase additives
1) Bentone organophilic clays
2) Bentone Gel
3) Thixcin R rheological additive
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8. A) Aqueous phase additives
1)Rheological associate thickeners:
 The rheoluxe family of rheology modifiers are non-ionic polymeric thickeners designed
specificity for the personal care market.
 Rheoluxe consist of urethane based and polyether Polyol based associate thickeners with
superior performance in difficult system such as those containing high salt levels or with
extremes in pH.
 Due to its structure, Rheoluxe is soluble in water, but associates with lipophilic materials
to build viscocity.
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2) Hectorite:
 Is a unique swelling clay which contain higher swelling capacity ,greeter gel
strength, no crystalline silica .
 Hectorite is able to form a strong ,stable viscous gels.
 Hectorite is a very effective thickener of water.
 Hectorite is a unique swelling clay offering several advantages.

11. o Hectorite’s special properties, compared with bentonite, are:
• Lower iron content
• Lighter colour
• Higher swelling capacity
• Greater gel strength
• No crystalline silica
Due to its small size, platelet shape and large surface area, hectorite is able to form
strong, stable viscous gels.
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12. 3)Bentone hydrophilic clays :
 Bentone MA, EW, and LT rheological additives provide thixotropy and suspension control to the aqueous
phase.
 Bentone MA and EW additive form gels by producing an open, 3-dimensional network of the individual clay
platelets.
 The two products are stable across the range pH 6-11 and offer good tolerance to electrolytes.
 Bentone LT forms a similar network, but it is strengthened by the presence of a special cellulose, greatly
enhancing stability and thickening characteristics.
 Bentone LT is stable across a broader range, pH 3-11, and is also the least electrolyte sensitive product.
 Bentone MA and EW are in compliance with ECOCERT; The ecological and organic cosmetics standards.
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13. B) Non aqueous phase additives
1) Bentone organophilic clays:
 Hectorite is now reacted with special vegetable quaternary ammonium salts to
produce organoclays able to thicken and gel organic liquids.
 The correct choice of Bentone additive is determined largely by the polarity of the
system to be thickened.
 Bentone additives need to be efficiently dispersed using high-shear equipment and
then to be activated with the optimum level of a chemical activator, such as
propylene carbonate.
 Bentone organoclays form thixotropic gels by developing hydrogen bond bridges
between the edges of adjacent platelets.
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16. 2)Bentone Gel:
 Bentone gel additives are optimally dispersed and activated predispersions.
 Benefits include:
• Optimally dispersed.
• High-shear dispersion not necessary
• No polar activation required
• Easy to handle and use
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17. • can be added at any appropriate and convenient stage in manufacture.
 A wide range of gels made from various cosmetics oils, esters and solvents are
available.
 The use of a Bentone gel enables you, the formulator, to achieve the maximum
efficiency from the organoclay without the need for careful shearing and
activation.
 On the production scale, time is saved and the highest degree of reproducibility
attained, leading to potential cost savings.
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18. 3)Thixcin R rheological additives:
 For the highest degree of thixotropy in aliphatic liquids, Thixcin R additive is the product to
use.
 In addition to its effective rheological properties, it gives water repellency, stabilises
emulsions and acts as a stiffening agent in lipsticks and ointments.
 It can also be used as a dry binder in pressed powder systems.(Where high-temperature
resistance is needed, Bentone or Bentone gel additives are recommended).
 Thixcin R is a castor oil derivative. It requires temperature-controlled activation within the
range 55-60°C (130-140°F) and high-shear mixing to develop its full structure.
 Thixcin R is in compliance with ECOCERT; The ecological and organic cosmetics standards.
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19. Applications
 Stick products (lipstick and antiperspirant)
•Maintain homogeneity in molten and setting stages
• Gain improved pay-out
• Increase high-temperature integrity
• Eliminate oil migration
• Reduce “creasing” around lips and eyes
 Mascara
• Improve film-build
• Increase water-resistance
• Eliminate oil migration
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20.  Emulsions
• Elevate drop-point temperature of water-in-oil creams
• Eliminate syneresis
• Improve emulsion stability
• Enable cold-process emulsification
• Create novel viscosity effects
 UV Sunscreen
• Eliminate ultrafine Ti02 skin-whitening problems
• Enhance sun protection factor (SPF)
• Optimise use of sunscreen actives
• Reduce separation and settlement
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21.  Antiperspirant Aerosols
• Uniform distribution of active ingredients
• Soft and dry skin feel
• Significant less whitening
• Reduced separation and settlement
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24. References
 Rheology cosmetic brochure Dec 2013
 BYK BR CO rheological additives Web 1
 www.wikipedia.co.in
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