What Is the Importance of Viscosity in Cosmetics?
With so many products now available on the market, consumers expect certain properties and a certain level of performance from the cosmetics and personal care products they use every day. It is expected that these products will be effective, skin-friendly and enjoyable to use, with a pleasant sensory profile. As a result, manufacturers are seeking high-quality ingredients to help them meet these customer demands.
One crucial property for cosmetics and personal care items, from color makeup to shampoo and skin care products, is viscosity. But what is viscosity, and why is it so important?
What Is Viscosity?
In short, viscosity refers to a product’s thickness and a measurement of its rheological behavior. In particular, it refers to a product’s resistance to deformation, impacting how a material behaves when force or pressure is applied to it (for example, how the product flows when squeezed out of a bottle and how it feels when applied to the skin).
Why Is Viscosity Important in Cosmetics and Personal Care Products?
Viscosity is tremendously important in cosmetics and personal care products because it plays a role in determining everything from a product’s sensory profile to its stability. Understanding how viscosity works is key to being able to modify these properties to create the desired profile for any particular product.
If an emulsion is too thin, it is likely to destabilize, meaning the oil and water will separate. This can result in a product that needs to be shaken to remix or is simply too unstable to be effective. Viscosity is also important in formulations in which particles are suspended, such as color cosmetics with powdered pigments and mineral sunscreens. Without the proper viscosity to keep these suspensions in place, major stability issues will occur.
Viscosity is important for virtually every product within the cosmetics and personal care space. Products from toothpaste to color cosmetics to shampoo and conditioner are all impacted by viscosity. It affects not just the ways that a product can be used but also the overall consumer experience in using the product.
How Is Viscosity Measured in Cosmetics?
In our laboratories here at Applechem, we have two critical pieces of equipment that help us measure and monitor the viscosity of products. The first is a viscometer, which measures viscosity at a fixed shear rate. (Shear rate refers to the rate of deformation of the liquid.)
The second is a more advanced machine called a rheometer, which uses dynamic oscillatory measurement techniques to allow us to very slightly manipulate materials and then measure their feedback. This allows us to manipulate materials without disrupting their structure or to intentionally disrupt their structure and then measure their flow properties.
These tools are a crucial part of the quality-control process and are used on every batch of end-use products, ensuring they adhere to the fixed parameters required. We also use these tools to measure our various test formulations, working closely with our clients to design consistent, stable, and user-friendly products using our ingredients.
How to Enhance the Consistency, Volume, and Viscosity of Cosmetic Products
When designing and formulating any kind of cosmetic or personal care product, using the right rheological modifier can help to ensure the finished product has the viscosity, consistency, and sensory profile required.
Here at Applechem, we offer a number of quality rheological modifiers that can be added to your formulations to manipulate their viscosity as required.
Applecare PDS-300 is an advanced dispersing system for uncoated, hydrophilic color pigments designed to help formulators disperse these ingredients into oil for the purpose of creating color cosmetics. It also has a significant impact on a product’s viscosity and other rheological properties.
When trying to disperse high amounts of color pigments in a cosmetic formulation, PDS-300 prevents those pigments from sticking together again. This makes it easier to blend the entire formulation, resulting in a pleasant serum-like texture with highly homogenous color dispersion. Even a small amount of a quality dispersing aid like Applecare PDS-300 can make a big difference to the quality of finished color cosmetic products. Applecare PDS-300 is also ideal for dispersing active ingredients such as zinc oxide or titanium oxide in mineral sunscreens.
Sensogel NOVUS is an oil and water acrylate thickener designed to help thicken oil-in-water emulsions (the least costly and easiest type of emulsion to make and very common across the cosmetics and personal care industry).
Many natural thickeners, such as xanthan gum, can cause issues in these products, leading to an undesirable “gummy” texture. Sensogel NOVUS offers a clean and fresh sensory profile to any type of oil-in-water emulsion, regardless of its overall viscosity. It is an easy and versatile tool for formulators of many different types of cosmetics products.
Sorbithix L-100 is an associative nonionic thickener for cleansing products such as shampoos. When soap is added to water to create these formulations, the resulting product is thin and watery. Sorbithix joins to structures called micelles, linking them together and preventing them from flowing, thereby changing the viscosity of the product. The resulting product is less water-like and more resembles a typical shampoo, flowing smoothly but with plenty of body. Moreover, Sorbithix is designed to work with modern sulfate-free surfactant systems, allowing formulators to thicken the milder surfactants preferred by current consumers.
If you would like to learn more about any of the products we have discussed in this post—or about any of our other rheological modifiers, such as our G-GEL and OleoFLEX lines—please feel free to reach out anytime. We believe in being generous with product samples, and we would be happy to provide any you require. Our team can also advise you on the best ways to use our products in your cosmetics and personal care product formulations.
Contact Applechem today or request a sample to learn more about how we can help increase the effectiveness and efficiency of your personal care or cosmetic product lines!