I’m quite happy with my shampoo bar. However, it’s only available from 1 shop and they’ve been known to change their formulation.
The current formulation uses the following ingredients: SODIUM COCOYL ISETHIONATE, AQUA (WATER), GLYCERIN, COCAMIDOPROPYL BETAINE DODECANOIC ACIDS, PARFUM (FRAGRANCE), OLEA EUROPAEA (OLIVE) FRUIT OIL, SIMMONDSIA CHINENSIS (JOJOBA) SEED OIL, PRUNUS AMYGDALUS DULCIS (SWEET ALMOND) OIL, PERSEA GRATISSIMA (AVOCADO) OIL, CHONDRUS CRISPUS EXTRACT, URTICA DIOICA (NETTLE) EXTRACT, RUBUS IDAEUS (RASPBERRY) FRUIT EXTRACT.
The formulation clearly uses SCI in noodle/needle form to give the soap bar some texture, which really works well to get the soap into my hair so I want to replicate this. I’ll have to look up how to make a formulation without melting the SCI.
A similar recipe using SCI and Cocamidopropyl betaine can be found here although they use SCI powder. Also they add BTMS-25 which is what I already was going to get for my conditioner. Humblebeeandme also has a recipe including BTMS. Wait, this is what I was looking for! Humblebeeandme figured out how to leave the noodles intact. They use SCI/SCS/glycerin/oil instead of SCI/coco beatine/glycerin oil, and probably quite a bit less glycerin, but it’s close enough. The idea is that they use just enough water to dissolve the surfactants together but not enough to dissolve them completely. Alternatively, the secondary phase can be melted separately and mixed with the cold surfactants to melt them together but not melt them completely.
The 3 formulations I could find use about 90% surfactants, 2-4% humectant/binder, 4-6% oil.
Surfactants
- Sodium Cocoyl Isethionate (SCI) noodles
- Cocamidopropyl betaine
- BTMS-25
Humectants / binders
- Glycerin – in original formulation probably used to keep the bar from cracking
- Hydrolyzed protein – but I don’t want protein
- Agar
- Carrageenan
Oils
I’d like to use some lighter oils than the Kruidvat bar:
- Sunflower oil
- Almond oil
- Argan oil
Formulation
Taking the savvyhomemade formulation and the humblebeeandme one as inspiration, this is the formulation I would like to try:
- Primary phase
- 50% SCI noodles
- 29% Cocamidopropyl Betaine
- Secondary phase
- 2% HEC
- 4% BTMS-25
- 5% glycerin
- 1% panthenol
- 2.75% water
- 0.25% citric acid 50% – aim for pH 4.5-5.5
- Tertiary phase
- 5% light oil (sunflower, almond, argan, includes fragrance oils)
- 0.025% vitamin E
- 1% Geoguard
Would need to get/build myself some sort of soap press though.