Total Surfactant Load - Shampoo Bars

AdmiralRedBeard

Hi,
I was wondering if someone that has experience in creating shampoo bars can answer a question regarding surfactants. I have read that the total surfactant load for hair care products should be formulated at around 30 to 40%. I found a formula from the Swift Crafty Monkey blog that I was trying to make my own adjustments to. The blog states that the powdered surfactants should range from 50 to 65% and the liquid surfactants should range from 10 to 26%. When I created my version, I have about 47% powdered surfactants and about 22% liquid surfactants. Based on the active level of my surfactants, I have a total surfactant load of 51%. The only way to reduce that number (closer to 40%) is to reduce the total % of the surfactants from 70% to 55% but I think that will also reduce the hardness of the shampoo bar.
Here is my formula:

Ingredient	% in Formula	Actives	Total Surfactant Load
Sodium Cocoyl Isethionate	27.27%	84%	22.91%
Sodium Lauroyl Sarcosinate	20.00%	95%	19.00%
Cocamidopropyl Betaine	13.64%	30%	4.09%
Coco Glucoside	9.09%	55%	5.00%
Shorea Robusta (Sal) Seed Butter	6.35%
Orbignya Oleifera (Babassu) Seed Butter	5.20%
Behentrimonium Methosulfate (AND) Cetearyl Alcohol	4.90%
Cetyl Alcohol	3.00%
Stearic Acid	3.00%
Gluconolactone (AND) Sodium Benzoate	1.50%
Panthenol	1.50%
Hydrolyzed Quinoa Protein	1.01%
Propanediol	1.00%
Fragrance	1.00%
Hydrolyzed Baobab Protein	0.66%
Glycine Betaine (Beta vulgaris (Beet)) Sugar Extract	0.55%
Hydrolyzed Rice Protein	0.34%
TOTALS	100%		51%

Can you tell me if this formula is acceptable? Are there better alternatives? The shampoo bar formula requires refrigeration to harden the bar. I haven't had a chance to see if it remains hard in normal conditions.

Thank you in advance for any tips, help or pointers that you can provide.

Bobzchemist

The surfactant load for shampoo bars should be 80-100%. The 30-40% number is only for liquid shampoos. The increased surfactant level is why there's a market for shampoo bars to begin with, so consumers don't have to pay for the 60% water that's in a typical liquid shampoo.

AdmiralRedBeard

Thank You, Bob! I really appreciate your reply. I need to tweak my formula a bit because the bars soften a bit too much when left out in room temperature.

bobter6

Thought I would chime in here since I do have experience with shampoo bars.

I agree with Bob. The total of the surfactant should be 80 to 100 percent. You probably need more powdered surfactants. Try 30% SCI and 30% Sodium Coco Sulfate Needles or powder, or SLSA with your liquid surfactant. If you melt down just your surfactants and they harden at room temp, then you will know that it is something in your other ingredients that is making them soft.

In your final formulation, you might also reduce the butters as that may be the reason for the softness at room temperature. 

AdmiralRedBeard

Thank you, bobter6. I really appreciate your advice. I have modified my formula to include your suggestions and will give it a try. I am finding that cosmetic chemistry is very fascinating and frustrating at the same time. In the end if I can get a product that performs as expected then it is all worth it. 

bobter6

I hope it works for you.