Foams bring lightness to any product, including cosmetic creams. Rich creams for the ideal sun protection, for faster wound healing or for concealing skin impurities are often very thick and difficult to apply. Either certain skin areas are forgotten or are treated irregularly, or the wound is rubbed even more. In a joint project between the Swiss dispersing equipment manufacturer Kinematica and a test laboratory for cosmetic and pharmaceutical products, the influence of foaming a cream on the application properties was elaborated. The application onto the skin and the absorption into the skin were investigated in detail. The results of the test are interesting for customers and manufacturers.
Air-foamed cream for the tests in the test laboratory.
How creams can be foamed?
The cream was foamed using Kinematica's membrane technology MEGATRON® MT-MM. This is a special unit to produce a very fine foam (or emulsions), based on a dynamically enhanced membrane. The desired gas, in this case air, is forced through the porous membrane into the product. The dynamic shaft of the MT-MM allows the controlled detachment of the air bubbles and thus their size and size distribution. This membrane technology has a low energy input which is ideal for heat- or shear-sensitive materials often found in cosmetic products. It leads to an improved cream quality and properties. In addition, the introduction of air through the membrane allows the production of a very stable foam without the addition of additives.
A water-based cream was used for the experiments. The cream was tested unprocessed, without foaming, and on the other hand, a test was made with an air input of 45%. The two creams were tested and analysed in the test laboratory for pharmaceutical and cosmetic products.
Dynamically enhanced air bubble detachment on ultra-fine porous membrane.
Foaming improves quality
In a first test, the force required to apply cream onto the skin was measured. It was found that the foamed cream needed about 10% less force than the reference (non-foamed) cream. This means that applying the cream to a wound is easier and the risk of rupturing the wound is minimized. A homogenous application of the cream is guaranteed to maximize sun protection and avoid cream-free areas on the skin. In addition to this, penetration through a plaster pad was measured. Cream was applied to a Derma Plast wound dressing patch simulating the skin. The mass loss was measured after 4 h of action at an ambient temperature of 37 °C and 20% humidity. The results show that the foamed cream loses more mass, which can be equated with improved penetration capacity.
Application specialist at Kinematica, Ruedi Wuffli, is enthusiastic: "By simply introducing tiny air bubbles, we improve the spreading of the cream on the skin and, even more, its absorption into the skin. So not only manufacturers benefit by saving material, but also the consumers with improved cream properties."
Measurement of the force for application to the skin and wound dressing plaster filled with cream for penetration measurements. (Source: Gausstech Ingenieurbüro GmbH)
More tests to be planned
"The results are promising," says project manager and initiator of the project Lea Meier-Pokorny. "We now have the first proof-of-concept, but now we would like to do the endurance test with cosmetics manufacturers and test with their products. I can also well imagine that this application in pharmaceutical creams/ointments could be very interesting."
In order to continue the tests, the project team is dependent on the willingness of cosmetics and ointment manufacturers to test this process on existing or new products. Companies or individuals interested in testing or the results can contact Kinematica directly.