Giorgiana Giancola PhD – Kobo Products, US COLOUR COSMETICS Overview of colour dispersions in cosmetics Colour cosmetics are a ubiquitous element of personal care products, owing to the diversity of applications in which colour can be used. End-use applications include liquid and powder foundations, m o BB creams, concealer, blush, eye liner, c . e l i eye shadow, lipstick, mascara, skin care f e u g and sunscreens. The colouring material r o m . in a particular formulation depends on the w w desired colour effect. For example, in the w case of a shimmering eye shadow, a one- hundred micron interference flake type help reduce the aggregates to make are fully dispersed. By using dispersions, material could be used, whereas in the smaller size pigments. Treatments reduce the internal forces are reduced thus limiting case of a foundation, pigments less than the friction and adsorption on pigments re-agglomeration and reduced settling for one micron are used for a skin tone match. so more concentrated dispersions can be the most effective product. To formulate with pigments in powdered achieved. In addition to the previously mentioned form requires proper handling and Pigmentary grade pigments encompass pigmentary grade pigments are transparent processing prior to and during formulation. titanium dioxides (TiO2), iron oxides, and iron oxides. These useful materials exhibit Using colour dispersions alleviates these lakes which are useful materials for a a natural finish on the skin (Fig. 1). types of intermediate steps and offers chemist to employ in colour formulations. Additionally, they are known to contribute benefits of colour development with Typically, particle sizes of these materials to UV attenuation by boosting SPF and consistency of batches. Dispersions of are greater than 0.2 microns suffering the adding UVA protection in sunscreens. metal oxides and organic pigments in common drawback of agglomeration within These materials provide a tint to a formula multiple carriers are typically available. formulation. Particle size of the aggregates for the purpose of reducing the appearance Only homogenisation may be required to is an important parameter since it has of whitening, and chalkiness. In ethnic have a successful, final product based direct correlation to colour strength, gloss, products, transparent iron oxides provide on a colour dispersion. and opacity. In theory, the highest colour a natural look through the balance of intensity generates more opaqueness and transparency and coverage. Dispersions of Dispersion overview is achieved when the dispersion particle transparent iron oxides tend to agglomerate A material defined as a dispersion is size in formulation is at a size closest to more than the traditional type due to characterised as particles that are their primary state. Colour dispersion their smaller size resulting in difficulty in dispersed in a continuous phase of a materials boast small size particles which dispersing these particles. The solution different composition. Dispersions are is to use dispersions and surface treated structured to include a pigment, a vehicle, FAF4OTRR FAS55ERSI powders of transparent iron oxides for easy and a dispersant. First is the vehicle. incorporation into formulation. Suitable This is essentially the liquid that the vehicles of these particle materials include particulate medium is dispersed in. silicone emulsifiers, esters, and volatile The next element is the dispersant. non-D5 silicones. The dispersant functions to assist in wetting out the pigment, prevent settling, The motivation for and stabilise the pigments by ensuring using dispersions pigment separation in the dispersion. There is a large motivation behind using Wetting out the pigment is important to colour dispersions in formulations in increase the concentration of the pigment lieu of powdered pigments. Using a in the chosen vehicle. Often the pigment dispersed material alleviates the need for includes a surface treatment. This is the grinding, providing for reduced handling. solid being dispersed. The treatment aids These types of materials facilitate high in helping to wet out the pigment, achieve loading levels of solids in formulations. a uniform dispersion, and allows for With that said, a noteworthy achievement Figure 1: Drawdowns displaying the highly a higher solid content. Additionally, natural appearance of transparent iron oxide of these dispersions is the ability to obtain treatments can help to neutralise a charge dispersions (left) versus a traditional colour full colour development in formulations. on the outer surface of a pigment and to dispersion (right). Using a dispersion that imparts higher May 2014 PERSONAL CARE 29 COLOUR COSMETICS colour strength of pigments provides (ITT) treatment. Furthermore such as liquid and cream more room in a formula for other materials. these pigments impart gloss. foundation, cream-to-powder A highlighted feature particularly for the Pigments prepared in this makeup, lipstick and blush. formulator is that these dispersions are manner include TiO2, iron A noteworthy dispersion easy to incorporate with mixing and oxides, and organic lakes. in this category is the homogenising. Since batches are These types of dispersions octyldodecanol (OD) with consistent this will eliminate some colour have preferred use in jojoba ester treatment (Fig. 3) correcting issues and generally colour emulsions (W/S, W/O, S/W, for natural formulations. This dispersions offer better stability in a and O/W). They may also be natural pigmentary dispersion formula. Finished products offer improved used in anhydrous, non-volatile series is Ecocert approved for wear and pleasing aesthetics such as and volatile systems. Finished 2014. Solids content is high better skin feel since incorporated pigments emulsion formulations include ranging from 55%-75%. are treated. Dispersions are also easy liquid and cream foundation, These materials are applicable to use for colour correcting and better cream-to-powder make-up, in emulsions, and hot pours. batch consistency of colour or concealer, mascara, lipstick, transparency. Colour consistency between and blush. In anhydrous Dispersions in batches for reproducible results means systems these colour silicone emulsifiers global plants will have uniformity since dispersions can be successfully Falling under the category of there is access to the same materials. used in eyeshadow, concealer, dispersions in silicone With these materials, there are fewer and lipsticks. Synthetic wax emulsifiers is a range of issues with streaking and better mass dispersions using organic products ideal in emulsion tone to skin as in the case of foundation lake pigments possess higher systems (W/S, and W/O). formulations. From a manufacturing colour strength compared to These materials can also perspective these dispersions are highly non-dispersed lakes. Their be used in anhydrous non- cost effective. These products eliminate preferred use is in anhydrous volatile and volatile systems. the need for labour, equipment, and time non-volatile and volatile Preferred emulsion-based to plan processing and to make the actual systems. Also use can be applications are liquid and grind. This in turn contributes towards found in emulsions (W/S, W/O, cream foundation, cream-to- energy conservation in the manufacturing S/W, O/W). Anhydrous systems Figure 2: Displays the powder makeup, concealer, process. Furthermore, many incoming where these colour dispersions possibility to create a full mascara, lipsticks, and quality control checks on pre-shipments find applicability are in lipstick range of shades using a blushes. In anhydrous systems, are eliminated by utilising these materials. and blush. Emulsion systems single dispersion series. these are ideal in eyeshadow, Pigments such as iron oxides/transparent that are suitable are liquid and concealer, and lipsticks. grade iron oxides, TiO2, ultramarines, cream foundations, cream-to-powder FAS Dispersions [INCI: Pigment (and) organic lakes, and carbon black, in treated makeup as well as lipstick and blush. Cyclopentasiloxane (and) PEG/PPG-18/18 and untreated form, are typically used in Dispersions in isononyl isononoate Dimethicone] (Fig. 4) have good coverage, colour cosmetic formulation for enhanced and treated with isopropyl titanium very low odour, are very stable, have high skin feel and high colour intensity of the triisostearate (INBP) have hydrophobic solids content, and strong colour strength. pigments. The available pigmentary grade traits and are dispersible in oil. A full line An alternative to the traditionally defined dispersions on the market are plentiful of pigments and lakes are available on FAS dispersions is utilising a hybrid TTB with key emphasis on the varying carriers the market prepared in this way giving treatment in conjunction with FAS. This TTB available namely water/glycol, silicone the possibility to create a full range of treatment is a crosspolymer formed at the fluids, esters, hydrocarbons, natural oils, shades using a single series (Fig. 2). surface of the pigment offering versatility and volatile non-D5: ethyl trisiloxane, These types of materials are excellent to this dispersion by adding benefits such trimethyl siloxane, dimethicone and when applied to anhydrous non-volatile as super dispersibililty in silicone-based trisiloxane. This variety essentially allows and volatile systems such as lipsticks, systems, a hydrophobic and lipophilic for dispersion products to be used in blush, and other