Clay masks are a great addition to any product range for intensive treatment, salon (or salon-at-home) experiences and addition of innovative actives. However, masks do have additional formulation and stability needs to ensure you get a suitable shelf life…
We’ll take a look at some of the common issues, and how to solve them, here.
First, let’s take a quick look at why you would want to use charcoal or clays in masks, and their inherent properties (and formulation risks!)
− Charcoal is a great carbon source, and commonly obtained from bamboo. Charcoal provides detoxifying benefits to the skin and is able to absorb many times its weight in oil, making it a fantastic purifying ingredient. But, it is also a carbon rich source of nutrients for micro-organisms. It is also a very large particle, which means it needs significant stabilizing to stay homogenous throughout a formulation.
− Clays are mined from the ground and a naturally rich source of a variety of minerals. In fact, one of the reasons for selecting various clays is often for the specific minerals they contain, not just whether they are green, red or another color!
However, as they are mined from the ground, they should be treated before use otherwise they can contain some very deadly micro-organisms. Treatment may be using irradiation or heat treatment; if you want to use your clay in a certified natural or organic product, you need to avoid irradiation so will need to check with your supplier about the treatment method they use before purchasing if this is important for your brand.
Even when treated and delivered to you in a sterile state, they are mineral rich and a great food source for micro-organisms if exposed to contamination. Clay powders are also very large particles, so need significant stabilizing in formulas for a good shelf life.
So, the issues you face when formulating with these materials are ensuring:
− Good source of materials to begin with
− Good preservation
− Stabilizing the particles to ensure homogenous distribution throughout the shelf life
Now let’s take a look at how you can achieve these in more detail…
1. Start Pure
Activated charcoal is obtained by slow heating of bamboo or other selected timbers, in the absence of oxygen. Once the charcoal is created, it is then oxygenated to form activated charcoal and quality checked before being used in cosmetics. This means it should be supplied with a Certificate of Analysis (CofA) and an absent micro-organism count. Make sure any supplier you use to provide activated charcoal can provide you with this assurance and make sure you check the microbial content of every batch when it is supplied.
Clays MUST be treated by either irradiation or heat treatment. Find out the exact method your supplier uses by asking for it, as well as their CofA with each batch. It is also good manufacturing practice to check the microbial content of every batch when it is supplied to you too.
Once you’ve established every patch of your charcoal or clay is free from micro-organisms, make sure they are stored in dry conditions in the warehouse and dispensed from, using properly sanitized equipment in the presence of appropriately controlled air. In other words, dispense under Good Manufacturing Practice (GMP) conditions. Remember, these materials are potential food sources for micro-organisms so if they arrive sterile and are accessed in a sterile manner, they’ll remain sterile. But, given just enough water (even humidity!) and the introduction of even one micro-organism, and you’ll have a real problem, real fast.
» Continue reading to learn the potential solutions to overcome the issues while formulating clay masks!