I love adapting conditioner bars to be shaving bars! It doesn't take much...just look! (Originally from this post.) We add silk protein instead of oat protein for extra glide, and remove the cetrimonium chloride as it really isn't doing much for our skin.
SOLID SHAVING BAR
60% Incroquat BTMS (or 30% BTMS, 30% Incroquat CR)
10% cetyl alcohol
10% butter of choice - 5% cocoa butter, 5% something else, if you wish
5% oils - I like shea oil (2.5%) and fractionated coconut oil (2.5%)
2% hydrolyzed silk protein
2% hydrolyzed oat protein (or more silk protein, if you want)
COOL DOWN PHASE
3% cationic polymer like honeyquat or polyquat 7
2% hydrolyzed protein
2% fragrance or essential oil
Weigh into a heat proof container the Incroquat BTMS, cetyl alcohol, butter, cationic polymer, oils, silk protein, and hydrolyzed protein and place into a double boiler until they melt. Add the panthenol, dimethicone, cyclomethicone, hydrolyzed protein, and essential oil, mix well, then put into a mould and pop into the freezer or fridge until solid.
You can choose any oils you like. I chose shea and fractionated coconut oil as they are both very light and glidy on your skin, and have a very long shelf life. This is a huge consideration for making a product like this - these bars seem to last forever, so you want to choose oils with a long shelf life. If you are using something with 9 to 12 month shelf life - like sesame, olive, rice bran, and avocado (although avocado might be too dry) - you want to add 1% Vitamin E in the cool down stage. I would not recommend using any oils with a 6 month or lower shelf life as they will go rancid long before the bar is used up completely!
I find these are best made in 33 gram (1 ounce) to 45 gram (1.5 ounce) gram moulds as they seem to last forever and the larger bars are kind of annoying to swipe across your legs or face.
Join me tomorrow for fun formulating a liquid conditioner suitable as a shaving product!