Controlled-release Mechanisms of Fragrances

Aug 1, 2010 | Contact Author | By: Nitika U. Bhargava, Vijayanand P. Magar and Shamim A. Momin, Institute of Chemical Technology
Your message has been sent.
(click to close)
Contact the Author
Save
This item has been saved to your library.
View My Library
(click to close)
Save to My Library
Title: Controlled-release Mechanisms of Fragrances
controlled releasex encapsulationx wall materialx corex
  • Article
  • Media
  • Keywords/Abstract

Keywords: controlled release | encapsulation | wall material | core

Abstract: Fragrances are volatile and susceptible to oxidation, and can escape from a finished product over time. This limited longevity has led to the development of encapsulation and controlled-release techniques. The present article reviews methods for controlling the release of fragrance in personal care products, and describes their mechanisms of action.

View citation for this article

NU Bhargava, VP Magar and SA Momin, Controlled-release mechanisms of fragrances, Cosm & Toil 125(8) 42-49 (Aug 2010)

Excerpt Only This is a shortened version or summary of the article you requested. To view the complete article, please log in or create an account. Registration is Free!

Fragrance is a significant part of personal care products such as creams, lotions, body powders and shaving creams. It is formulated into nearly every personal care product via either a single raw material or a blend of two or three materials. Fragrance also plays a minor role in other cosmetics such as depilatories and hair-waving lotions, where it primarily masks malodorous ingredients. Fragrances are volatile; they react with other components and are susceptible to heat, moisture and various other factors. Therefore, it is important to control the release of fragrance raw materials over a desired site and at a desired rate.

Before a fragrance is incorporated into a cosmetic preparation, it is blended by a perfumer who mixes a variety of natural and synthetic raw materials to create a perfume compound with a multitude of chemical functional groups such as alcohols, aldehydes, ketones, esters, lactones, ethers and nitriles. In some cases, natural ingredients are less potent than their synthetic counterparts but on the other hand, only low levels of synthetic ingredients are permitted. In either case, it may be difficult to achieve the desired fragrance in a final product without adding high levels of ingredients. To increase the efficacy of fragrance raw materials, controlled release may be used. This novel technology improves the performance of natural ingredients, thereby offering a viable alternative to less accepted synthetic ingredients.


Lab Practical: Using Controlled-release Systems

  • Choose the appropriate wall material: one that is compatible with the formulation's ingredients.
  • The proper wall to core ratio must be selected, as it determines the encapsulation efficiency. 
  • The core and wall material should be non-reactive to one another. 
  • Formulators should decide up front the mechanism of release and the controlled-release technique. 
  • Adding colors to the encapsulates can impart interesting effects in formulations.

Excerpt Only This is a shortened version or summary of the article you requested. To view the complete article, please log in or create an account. Registration is Free!

 

Close

Table 1. Controlled-release mechanisms of encapsulation

Table 1. Controlled-release mechanisms of encapsulation

The choice of appropriate encapsulation technique depends upon the end use of the product and processing conditions involved in the manufacturing process.

Figure 1. Controlled release of a profragrance volatile molecule

Figure 1. Controlled release of a profragrance volatile

The release of a profragrance organic volatile molecule is shown here. Once released, the fragrance has its original characteristics.

Formula 1. Deodorant stick19

A.
Cyclomethicone (VS-7158, Momentive), 23.50% w/w
Hydrogenated Polydecene (Silkflo 364 NF, Ineos Oligomers), 20.00
Polyethylene Homopolymer (A-C 617, Honeywell), 3.00
Hydrogenated Castor Oil (Castorwax NF, CasChem), 2.00
PPG-Myristyl Ether (Promyristyl PM-3, Croda), 8.00
PEG-8 Distearate (Protamate 400-DS, Protameen Chemicals), 3.00

B.
Stearyl Alcohol (Lanette 18, Henkel Co.), 15.00
Aluminium Zirconium Tetrachlorohydrox Gly (Reach AZP-908, SummitReheis), 22.00
Silica (Cab-O-Sil M-5, Cabot Co.), 1.00
Encapsulated Dry Powder (Polycap, Haarmann and Reimer), 1.50
Fragrance (parfum) (Haarmann and Reimer), 1.00

Procedure: In a suitable vessel, combine A and heat to 75°C with mixing. Allow to cool during continued mixing at 70°C. Add B to A while mixing at 65°C. Pour AB into a suitable container and allow to cool.

Formula 2. Hair shampoo and conditioner22

Ammonium Laureth-3 Sulphate, 14.00% w/w
Cocamidopropyl Betaine, 2.70
Polyquaternium-10, 0.15
Light Mineral Oil, 0.05
Cocamide MEA, 0.80
Cetyl Alcohol, 0.42
Stearyl Alcohol, 0.18
Ethylene Glycol Distearate, 1.50
Dimethicone, 1.00
DMDM Hydantoin, 0.37
Fragrance (parfum), 0.60
Conjugate*, 0.50
Water (aqua), qs to 100.00%

*Prepared according to instructions in US Patent No. 7,534,157 from P&G

Formula 3. Detergent composition24

Monoethanolammonium salt of Alkyl Benzene Sulphonate, 18.00% w/w
Condensation product of 7 moles of Ethylene Oxide with 1 mole of C14-15 Alkanol, 33.00
Monoethanolamine, 2.00
Oleic Acid, 1.00
Ethanol, 5.00
Colloidal Silica, 2.00
Perfume microcapsules, 0.50
Water (aqua), other builders and fillers, qs to 100.00%

Next image >