How to Get Better Pigment Dispersions for Cosmetics
Colored pigments are used in numerous cosmetics products that many of us use every day. Foundation, blush, eyeshadow, lipstick, and many skin care and hair care products are just some of the common use cases for pigments in cosmetics.
In order to formulate these products, manufacturers must disperse these color pigments in with other ingredients. Dispersion is a process by which a dry ingredient is mixed into a liquid until the dry particles are completely and homogenously distributed throughout the liquid medium. The ideal result is an even, consistent, and long-lasting color. On the other hand, poorly dispersed color pigments can lead to issues with streaking, poor color stability, difficulty with color matching, and can even negatively influence formulation sensory and viscosity.
In today’s post, we will share some of our essential tips for getting better pigment dispersions for cosmetics products.
Know Your Pigments!
A great color dispersion for a cosmetic product begins with a strong understanding of available pigment options and their suitability for different formulation environments. Without this knowledge, your product may inadvertently be set up to fail no matter what you do later in the process. Here are some pigment properties to pay attention to when selecting your color blend:
Pigments may be organic (containing carbon) or inorganic (derived from natural minerals and ores). Whether a pigment is organic or inorganic can have a pronounced effect on your ability to properly disperse them into your formulation. As a general rule, organic pigments tend to be more difficult to disperse effectively and will usually require additional help in the form of coating treatments or wetting agents.
Pigments can be described in a number of ways. Hue refers to the color itself (e.g. red), luminosity refers to how bright or dark the shade is, and saturation describes the purity or intensity of the hue. Developing an understanding of how these attributes are visually represented from one end of the spectrum to another will go a long way toward making the task of color matching less tedious. For example, with organic lake pigments, the luminosity is a static value, meaning that adding more or less organic pigment will not change the brightness nor the darkness of the shade.
As previously mentioned, the dispersibility of a given pigment can be adjusted with specialty coatings (otherwise known as surface treatments). These coatings can affect the solubility of a pigment in oil or water or even the dispersibility in specific types of oil classes like silicones or natural esters. Making sure that your color pigment blends are compatible with the rest of your formulation will set you up for success.
In other words, it is a very good idea to research pigments thoroughly and explore different options before selecting the ones you will use.
Choose the Right Wetting Agent
Scientifically speaking, a wetting agent reduces the surface tension of a liquid. Wetting agents are also known as surfactants and are used to help spread a liquid over a solid surface and enable water and oil molecules to adhere to one another.
Poor pigment wetting can lead to shade matching issues as well as causing colors to shift post-processing. The result? A cosmetic product that is not the color you intended or which has an inconsistent or weak hue. The right wetting agent, on the other hand, offers more consistent color matching, reduces color shifting, and improves the stability of your product.
Choose the Right Dispersant Aid
Dispersing a pigment into your cosmetic formulation also requires a dispersant aid. A dispersant aid helps to improve the separation of the dry ingredient particles. Ensuring proper pigment separation in the dispersion enhances the stability of the finished product by preventing pigment particles from clumping back together again (a process called “agglomeration”). A good dispersant aid can be crucial to creating color-stable, lower viscosity products, especially when dealing with oil-soluble organic pigments. Different dispersant aids work well with different types of pigments, so pay attention again to overall compatibility. Ensure you are using the best one for the particular pigment you have chosen.
Find the Best Processing Conditions
Once you have chosen your pigment and other ingredients, it is time to apply mechanical force to combine the ingredients and refine particle distribution in your finished product. It will likely take some experimentation to get the most optimal heating time, grind time, and the exact steps to get the best possible end result. Dispersions containing fewer pigment particles will only require simple blending equipment like propeller mixers, while ones with high pigment content will require more powerful machinery like homogenizers or 3-roll mills to refine effectively. Don’t be surprised if this process needs to be repeated multiple times, as a good dispersion grind will need to have pigment particles in that sub-20 micron range for optimal color strength, homogeneity, and sensory.
Taking the time to find the best process at this stage will speed things up substantially when you are ready to bring the product to market.
Choose a Single Ingredient Solution
As you can see, the science of color can be tricky, and there are many steps involved in creating a quality color cosmetic product. One great way to ensure you are using the best possible combination of ingredients in your pigment dispersions (and save time!) is to choose an all-in-one solution that combines the functionality of a good wetting agent, surface treatment, and dispersant aid. This can eliminate many of the most common formulation issues discussed in this article, and even provide additional benefits like speeding up your development schedule, increasing space within your formulation for additional functional ingredients, and even making your entire sourcing and development process more cost-effective.
Using an all-in-one solution can also reduce the amount of heating, milling, and grinding time required. This not only speeds up your overall process but also decreases your heating and energy costs, saving you money and boosting your eco-friendly credentials.
In the next section, we will introduce you to our all-in-one pigment dispersion solution, Applemol PTIS Plus, and how it can help you to get better pigment dispersion in your cosmetics formulations.
What is Applemol PTIS Plus and How Can It Help?
Applemol PTIS Plus is our cutting-edge new pigment dispersal system for the cosmetics industry. Designed to solve several common formulation problems that can hold up development and release schedules, it is designed to help you make the best possible products and bring them to market in the shortest possible time.
Applemol PTIS Plus is an all-in-one dispersing emollient system that improves upon the known benefits of using pentaerythrityl tetraisostearate (otherwise known as PTIS, a popular wetting emollient used in color applications) with a powerful polymeric wetting-dispersant compound.
Benefits include providing for greater control of product viscosity, boosting the sensory profile, and eliminating the drag and cakey texture issues that customers dislike. It provides more consistent color matching and greater stability. It is highly flexible, universally suitable for use with all pigment types, and has a non-greasy, high shine emollient profile with a high level of water resistance.
Applemol PTIS Plus is also compatible with all standard emollient classes including natural oils, esters, hydrocarbons, and volatile silicones.
Extensive testing has shown that Applemol PTIS Plus performs consistently across pigment types and gives significantly improved viscosity control when compared with common single-function wetting agents. The data also show that Applemol PTIS Plus is so highly effective in wetting and dispersing pigments that particle size consistency and viscosity were improved right from the first step of the dispersion process.
How to Get the Most From Applemol PTIS Plus
Applemol PTIS Plus is easy to use and designed to make your product development and manufacturing easier. There are a few useful things to know to help you get the most out of it. In this section, we will share a few tips for using Applemol PTIS Plus to its full potential.
The amount of PTIS Plus you use will be proportional to the amount of pigment you are using. We recommend starting at around a one-to-one ratio between PTIS Plus and your pigment phase.
We recommend a maximum usage rate of 70% for Titanium Dioxide pigments, 60% for Iron Oxides, and 65% for organic pigments.
A heating step can improve the overall quality of your dispersion. However, this is not strictly necessary for organic pigments.
If you are using inorganic pigments, a heating step is required and a temperature of around 50C (122F) is recommended as a baseline. If possible, the optimal temperature range would be around 70C.
Learn More and Try Applemol PTIS Plus
We believe in being generous with samples as we understand that clients like to try out several options before settling on their final formulation. If you would like to try Applemol PTIS Plus for yourself, simply get in touch and a member of our team will be pleased to assist you.
If you have any questions about this or any other Applechem products, you are also welcome to contact us and we will assist you in any way we can.
We look forward to working with you and supporting you to keep creating the kinds of fantastic products your customers expect.