In the last post, what is a moisturizer and what goes into them were discussed in detail. There’s a considerable amount of science that go into moisturizers. Of course, that was just an extensive overview into the nature of moisturizers. A question you may have now is how you make them? In this post, I’ll go over how to formulate a moisturizing cream, how to set up the two immiscible phases, when to add the additives, and some pointers to enhance stability of these emulsions. If you’re ready, let’s begin part 2 of this journey.
Let’s recap on the purpose of a moisturizer: to hydrate the hair or skin and/or help retain moisture. Three broad classes of moisturizing agents function in these regards: emollients, humectants, and occlusives. Together, along with DI water, fragrances, stabliziers, preservatives, and actives, they constitute the moisturizing products you buy online or in stores. For this experiement, you’ll need the following equipments and materials:
- Lab mixer w/ clamp
- Hotplate x2
- Scale
- Beakers (5): 800mL, 400mL, 100mL, 50mL, 25mL
- Spatulas
- Pipettes
- Tongue depressors
- pH meter or strips
- Ingredients
- Lab notebook and pens/pencils; a standard notebook will do too
- Weigh boats/papers
Now, for our hypothetical moisturizing cream; here’s the IL for this product:
Ingredients: Water (aqua) (1), behenyl alcohol, sunflower oil (3), glycerin (2), capric/caprylic triglycerides (3), squalane (3), meadowfoam seed oil (3), cetearyl alcohol (3), sodium levulinate (4), glyceryl stearate (3), stearic acid (3), parfum (4), sodium pca (1), tocopherol (3), ceasalpinia spinosa gum (2), shea butter, mango butter (2), potassium sorbate, pomegranate extract (4), kale extract (4), sage leaf extract (4), sodium hyaluronate (2), aloe vera leaf juice (1), citric acid (5)
For the sake of relevance and simplicity, this cream is called Green Seasons Face Cream. It has a variety of moisturizing agents, a stabilizer, preservative, fragrance, emulsifiers, and pH adjuster. You’re free to take this formula and see if it works. The chemistry is there for a heavier cream. The percentages are can be random so long as you keep in mind that for a heavier cream, DIW will be 60-70% DIW, about 20-30% oil phase, and about 5% additives, 1-2% preservatives, and 1% fragrance (unless you want to be the next BBW). Only hitting the bench will determine whether this chassis will work. This is how the IL would be organized to formulate:
Phase 1: Add DIW to main container and begin high speed mixing, then add the rest of phase 1 materials to MCT. Mix well until batch is uniform (10 mins. minimum).
Phase 2: In a separate container, add gum and sodium hyaluronate in glycerin until solids are uniformly dispersed. Once phase 2 premix is uniform, add to MCT and mix until batch hydrates (20 mins. minimum). Heat MCT to 80-85C.
Phase 3: In a separate container, add phase 3 items and heat to 80-85C with mixing. Mix well until all solids have melted and premix is uniform. When MCT and phase 3 are at 80-85C, add phase 3 to MCT and mix well (20 mins. minimum). Cool batch to 40-45C.
Note: If you have a homogenizer, add phase 3 to MCT while homogenizing at 3500rpm for 5 mins.
Phase 4: At 40-45C, add phase 4 items to MCT one by one, mixing well between each addition. Mix until uniform (15 mins. minimum). Cool batch to 30-35C.
Phase 5: In a separate container, premix citric acid in DIW and mix until solids completely dissolve. At 30-35C, add phase 5 premix to MCT and mix well (10 mins. minimum).
Note: Depending on the pH already, it may not need to be adjusted. For a pH-balanced cream, aim for pH= 5.00-6.00.
There you have it. I present to you your moisturizing cream for the hands and body. Hope you had fun and I’m looking forward to the next class session. If you have any questions, feel free to reach out to me with the information provided on the contact page. Until next time everyone.
Greengen Labs 