How to make a lotion: EMULSIFIERS pt.1 – THEORY

LAB NOTES & SAFETY NOTICE
These are personal experiments for educational use only— not instructions and not for commercial or consumer use. By proceeding, you assume all risks related to safety, testing, and regulatory compliance.
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My Lab Notes: Emulsifiers and the HLB Mystery

Hello Hello! 😀

I’ve been spending a lot of time thinking about the “matchmakers” in my beakers: Emulsifiers. I’ve learned that since water and oil naturally want to stay apart, I need a substance that acts like a bridge—something that grabs the water with one hand and the oil with the other to keep them combined.

The “Double Personality” Discovery

I’ve documented that these molecules work because they have a dual nature:

• One part is Hydrophilic (water-loving).

• One part is Lipophilic (oil-loving).

The HLB Scale (My Reference Guide)

I used to find the HLB (Hydrophilic-Lipophilic Balance) scale a bit intimidating, but I’ve simplified it in my notes. It’s just a scale from 0 to 20 that tells me which side the emulsifier “leans” toward.

[If I feel like skipping the technical parts today… I can! 😄 But for my records, I’m keeping this summary here:]

• HLB 3–6 (The Oil-Lovers): In my experiments, these usually create W/O (Water-in-Oil) systems. I’ve noticed these are great for heavy, protective ointments.

• HLB 8–16 (The Water-Lovers): These are my go-to for O/W (Oil-in-Water) lotions. Most of the creams I make fall into this category.

My Emulsifier “Cheat Sheet”:

I’ve compiled this list of values for the materials I have in my cupboard so I don’t have to look them up every time:

• 4.0 – Lecithin (I’ve even tried the food-grade kind from the supermarket!)

• 5.0 – Cetyl alcohol (I record this as a lipophilic co-emulsifier to add “body”)

• 10.0 – Montanov 68 (A self-emulsifier that I’ve found works well on its own)

• 12.0 – Methylglucose sesquistearate (One of my favorites for light lotions)

• 16.7 – Polysorbate 20 (I use this mainly when I need to dissolve essential oils into water)

What the Numbers Don’t Tell Me

My biggest takeaway from these experiments is that the HLB number is just the beginning.

• Thermal requirements: My notes show that the number won’t tell me if I need to hit 70°C or if it’s a cold process.

• The “Feel”: I still have to get my hands in the beaker to see if the final cream feels “waxy” or “silky.”

(to be continued… 😄)