Like everyone else i want to use a preservative system for my cleansing products that is as gentle as possible. But as you may have experienced in business, if you use an inexpensive ingredient for some time, it is impossible to replace it with a more expensive product to get the same result.
I have used formalin 0.15%+ EDTA 0.2% pH <5 for some time without problem. But i want to make it more gentle without reducing the effectiveness and increasing the cost.
So i decided to add some CMIT MIT and reduce the amount of formalin.
My current plan is
Ingredients are water, SLES, CAPB, APG, cationic guar, Amodimethicone, fragrance NACL, citric acid.
What do you think about effectiveness of this combo this combo?
At what ratio and amount would formalin+ CMIT MIT has maximum effectiveness and be the least irritating?