Formulate his and hers Valentine's day cleansers

This is where I purchased my key ingredients:

Nikura ‘Energy’ essential oil blend — used for the charcoal bar.

Nikura ‘Sweet Dreams’ essential oil blend — used for the pink bar.

Check your usual suppliers for the remaining ingredients. Cetearyl alcohol, SCI, SLSA, glycerin, Lamesoft PO65, and tocopherol are all widely available from cosmetic ingredient suppliers.

Method:

1. 1. Weigh Phase A in a milk pan (if you have an electric hob) or use a double boiler. Follow the order of ingredients. 

2. 2. Start heating Phase A. When almost molten, add in Phase B ingredients.

3. 3. Stir slowly, avoid creating bubbles. 

4. 4. Remove from heat and allow to cool slightly.

5. 5. Add Phase C ingredients and pour into your chosen mould.

6. Allow the cleanser to harden overnight before demoulding. 

Use the remainder in the pan to check the pH. Create a 10% solution (1g cleanser and 9g distilled water) and check the pH. My charcoal bar has a pH of 4.96.

This formula covers more practical ground than it might look like at first glance. Here’s what you’re learning when you make it:

Working with anionic surfactant powders — SCI and SLSA are the two most commonly used surfactants in solid bars, and learning how they behave when melted and combined is a skill you’ll use again and again in shampoo bars, body bars, and other syndet solids.

Understanding the melt-and-press method — this formula uses a method where the cetearyl alcohol is melted, and the surfactant powders are incorporated into the melt. Getting a feel for the right temperature and consistency at each stage is something that only comes from doing it, and this formula is a forgiving one to practise with.

Balancing cleansing with conditioning — a cleanser that strips the skin isn’t a good cleanser, no matter how well it foams. This formula teaches you how superfatting agents like Lamesoft PO65 and emollient oils work alongside surfactants to leave the skin feeling clean but comfortable.

Checking the pH of a solid product — pH adjustment is a core formulation skill, and solid products require a slightly different approach (the 10% solution method). Practising it here, where the formula is simple, builds the habit before you move on to more complex systems.

Customising a base formula — by making two variations from one base, you’re already practising the principle of adapting a formula to different purposes. That’s the thinking that separates a formulator from someone who follows recipes.

By the time you’ve finished both bars, you’ve covered five foundational skills in a single session. That’s a productive afternoon.

Once you’ve made the base version and you’re confident with the method, try some swaps:

Macadamia or jojoba oil → sweet almond oil, avocado oil, or olive oil. They are all skin-friendly emollients that work well in solid bars. Olive oil gives a slightly heavier feel, whilst sweet almond is light and well tolerated. Keep the total oil percentage the same.

SLSA + SCI → adjust the ratio. If you find the lather too fluffy, increase the SCI and reduce the SLSA. SCI produces a creamier, denser foam. If you want more bubbles, alter the balance the other way. The total surfactant percentage should stay around 40%.

Mica or charcoal → other colourants. Cosmetic-grade clays, such as kaolin or French green clay, can replace the colourant and provide gentle cleansing or soothing benefits. Some clays also contribute a natural colour. Soap-safe colourants are another option if you want bolder shades.

Add a conditioning extra. Panthenol (provitamin B5) at 0.5 to 1%, hydrolysed proteins (silk, oat, or rice) at 0.5 to 2%, or colloidal oatmeal at 0.5 to 3% can all be added to Phase B. If you add these, reduce the oil percentage by the same amount to keep the formula balanced.

The principle is the same as always: once you understand the structure, you can adapt the individual ingredients to suit your skin, your preferences, or what you have on hand. If you’re not sure which essential oils to pair or how to build a blend that works for a rinse-off product, Fiona, our AI Lab Assistant, can help you work that out.

SAFETY NOTE

This formula is designed for personal use as a rinse-off body cleanser. It’s best suited to normal or oily skin. If you have sensitive or dry skin, this may not be the right formula for you due to the surfactant concentration, as Timi has noted in the comments on the original post.

If you’re using essential oils, check the IFRA guidelines for maximum safe usage levels in rinse-off products and be aware of any known sensitisers in your chosen blend. The 1.5% essential oil level in this formula is within typical safe ranges for rinse-off use, but always verify with the specific oils you’re using.

Always perform a patch test before using a new formulation on your body. Apply a small amount of lather to the inside of your wrist, leave for 24 hours, and check for any irritation.

When sourcing your ingredients, make sure you purchase from reputable suppliers that provide proper documentation, including Certificates of Analysis (COAs) and Safety Data Sheets (SDS). If you’re using any fragrance materials, request the IFRA certificate.

This blog post is for educational purposes only and is not intended to replace cosmetic safety assessments required for commercial sales. If you plan to sell products, a formal safety assessment by a qualified assessor is a legal requirement in the UK and EU.