Shampoo is making hair rough and dry
I have recently formulated this shampoo. It contains
Sles (70%) 8%
Tween 60 1.5%
Tea tree oil and tocopherol 1.5%
Polyquartenium 7 3%
Quartenized panthenol 1%
Hydantoin 1% as preservative
Now the issue here is that i have had very few complaints recently which say that their hair become dry and rough after the using the shampoo. These complaints represent like 3 out of a 100 people who have used this product nevertheless i would like to resolve this issue.
Kindly suggest any tweaks or substitutions i can make to this issue go away.
Thanks in advance.