Liquid Makeup Brush Cleaner (Free Formulation)

First, what is a brush cleaner?
Brush cleaners are a surfactant-based product that cleanses various types of makeup product as well as cleanse dirt, oil. and bacteria from your brushes. Brushes can be synthetic and also natural hair bristles. Form my understanding, it should be formulated to a shampoo with great cleansing power. Let's review the ASMs of different products.
ASM of Different Products:

• face wash: <10% 

• detergent for intimate use: <10% 

• shampoo: 10%-15%

• shower gel: 15%-20% 

• bubble bath: 20%-25%

Brushes can be synthetic or they can be natural hair because of that I am going to be formulating the ASM to of that of a shampoo. I am going to go with the high end as we are really trying to cleanse makeup from the brush. I am going to use a combination of
Sodium Lauryl Sulfate (SLS) and Cocomidopropyl Betaine. The ASM of both Sodium Lauryl Sulfate and Cocomidopropyl Betaine is 30%. Since SLS is really good at cleansing, I am going to formulate that to 5% ASM. While the Cocomidopropyl Betaine, I am formulating to 10% ASM. Blending the two surfactant will make the product more mild. SLS can be thickened with salt. It is important to know the salt content of your amphoteric surfactant. The one I have from making cosmetic has a salt content of 5%. I have included the calculation of the ASM and of the Salt in the calculation section. For some hydration, I want to include 5% glycerin. For some conditioning, I want to include 2% Polyquaterium-7. The combination of glycerin and polyquaternium-7 will ensure that this formulation will not strip natural hair brushes. You could also add 1% of a hydrolyzed protein. This is a high foam formulation. A little goes a lot way. I really like to wash my brushes with a brush mat. I got mine from Amazon. 

Calculations:
100-(2+5+16.67+33.34+0.50)=42.49
ASM Calculations:

• Sodium Lauryl Sulfate 5% ASM

  • 30*0.1667=5.001 

• Cocomidopropyl Betaine

  • 30*0.3334=10.002 

• 5*0.3334=1.667 Salt Content

Method:
Sanitize all your equipment, containers, and workspace. Gather all your ingredients and make sure that your notebook is set up. In a glass beaker, add all your phase A ingredients. In a separate, larger beaker. Weigh out phase B. Gently pour phase A into B to create phase A/B. Stir gently until everything is homogeneous. I would check and adjust the pH at this point to 5.5. Add phase C as needed. You can also add salt 0.10% at a time to decrease the viscosity if it is too thick. Stir until the ingredients are uniform. Pour into the final packaging. Be sure to label and date your latest formulation.
Adjusting pH:
Adjusting pH (Dilution Method): Get two beakers; one will be used as our washing beaker, and the other will be used to make the dilutions. The main thing with making dilutions is you want to make enough that the probe can be covered. You can weigh out 1 gram of product and 9 grams of distilled water to make a 10% dilution. Or you can weigh out 2 grams of product and then 18 grams of distilled water. Get your pH meter out and rinse with distilled water into the other beaker I had you get. Dry off the meter with a lint-free product. Mix it well and take the pH. If you are using strips, do not make a diluted solution no matter the viscosity; or the pH will be way off. Do not put the strips directly into the product. Even if you are taking the pH of the product directly, you want to add your product into a separate beaker. Wait for the reading to be stable, take a note of the pH, and discard the Sample after. Then put the product on the scale and tare it. Add 0.10g either the 50:50 citric acid solution (to lower the pH), the sodium hydroxide (to raise the pH), or TEA (to raise the pH of the product). Stir well, then wait at least 1 minute before making another dilution. Keep repeating the process until you get the desired pH. You will be surprised how much it may take. I recommend making a bigger batch than you want so you can account for that.
Substitutions and Alterations:
Substituting ingredients will change the final feel, viscosity, and overall effect of final product. percentages and formulating procedure may need to change with substitutions. These substitution suggestions are just suggestions and have not been tested to work.
To find out where to purchase ingredients check out the ingredient suppler page. 
Any alteration that you make, ensure that the total formulation is 100%. 

• You can replace 10%  of the distilled 

• You can replace the SLS with SLES. The SLES that I have  is the same ASM. So just make sure the ASM is the same, if not you will need to calculate it. 

• You can replace the hydrolyze protein with another one. 

• You can replace the cocamidopropyl betaine with another amphoteric surfactant. 

• You can use Crothix to thicken this instead of salt.