Home Cosmetic Science Talk Formulating Advanced Questions Comparison of two shampoos with same ingredients ratio but different amounts

• # Comparison of two shampoos with same ingredients ratio but different amounts

Posted by on February 1, 2022 at 7:49 am

If we compare these two shampoos that the ratio of ingredients are the same, only one has double the amount of ingredients compared to another

A: in active percentage
SLES 6%
CAPB 1%
APG 1%
EDTA 0.1%
Cationic guar 0.1%
Amodimethicone in emulsion 0.15%
Formalin 0.15%
Citric acid
NACL
water
pH 5

B: in active percentage
SLES 12%
CAPB 2%
APG 2%
EDTA 0.2%
Cationic guar 0.2%
Amodimethicone in emulsion 0.3%
Formalin 0.15%
Citric acid
NACL
Water
pH 5

Viscosity of both about the same

1. woud micelles shape and size be the same in both or different?

2. In theory would cleaning power, conditioning and mildness of both be the same if we use B in half amount of A?
2 Members · 4 Replies
• 4 Replies
• ### OldPerry

Member
February 1, 2022 at 1:57 pm

1. Different
2. In theory, yes. In practice maybe not because B might never fully hydrate to reach those half concentrations.

• ### Abdullah

Member
February 1, 2022 at 2:12 pm

@Perry thanks
If we use only one surfactant, would the micelle shape be different between 6% and 12% surfactant concentration?

because B might never fully hydrate to reach those half concentrations.”
Sorry i didn’t get the idea from this point. Can you explain it a bit more.

• ### OldPerry

Member
February 1, 2022 at 2:18 pm

would the micelle shape be different between 6% and 12% surfactant
I don’t know. You would have to do a phase diagram to determine the substructure of the solution.

Can you explain it a bit more
All I was trying to point out is that when you put solution B in your hand and mix it with water, it will take some time to dilute completely so that it matches the concentration of A.

Suppose you took a sample of B, put it in your hand, poured water on it. The water would initially be on top of the sample and none of the concentrations will change except at the very surface of the sample. The middle of the sample will still have the same concentration as when it started. Only as the water migrates through the sample will the concentrations start to match B with A. But if you don’t give it enough time to dilute, the concentration across the sample will be inconsistent. It is this inconsistency that might matter (or maybe not).

• ### Abdullah

Member
February 1, 2022 at 2:53 pm

Perry said:

would the micelle shape be different between 6% and 12% surfactant
I don’t know. You would have to do a phase diagram to determine the substructure of the solution.

Can you explain it a bit more
All I was trying to point out is that when you put solution B in your hand and mix it with water, it will take some time to dilute completely so that it matches the concentration of A.

Suppose you took a sample of B, put it in your hand, poured water on it. The water would initially be on top of the sample and none of the concentrations will change except at the very surface of the sample. The middle of the sample will still have the same concentration as when it started. Only as the water migrates through the sample will the concentrations start to match B with A. But if you don’t give it enough time to dilute, the concentration across the sample will be inconsistent. It is this inconsistency that might matter (or maybe not).

Got it

Thanks a lot