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What can be the cause of scalp irritation one or two days after washing hair with this shampoo?
I have used this formula of shampoo for about 3 months. The cleaning, foam and conditioning effect is good. At first everything was good but recently my scalp starts stinging one or two days after washing my hair and when i wash it again the stinging is gone but after one or two days it starts stinging again.
Also When i start exercising and my body start sweating that stinging increases and then decrease.
what can be the problem?
over conditioning
Not good cleaningAny of the ingredients
Or something elseShampoo ingredients:
water
active SLS 2%
active SLES 8.8%
active CAPB 1.8%
Active lauryl Glucoside 1.3%
Active decyl Glucoside 0.5%
Amodimethicone emulsion 2.5%(0.75% silicone)
PQ10 0.1%
Quar Hydroxypropyltrimonium Chloride 0.1%
Xanthan gum 0.3%
Phenoxyethanol 0.9%
Caprylyl Glycol 0.1%
Citric acid 2%
Rose fragrance oil 0.3%
pH 5.1Decyl Glucoside i use has expired on march 2021😉.
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15 Replies
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You probably have an allergy to one of the ingredients (contact dermatitis). https://www.webmd.com/allergies/chemical-allergies
According to WebMD, those reactions appear 24-48 hrs after application. -
@Syl thanks a lot.
Of course i will check each ingredient but any idea which one to check first?
I think decyl Glucoside, fragrance and xanthan gum would be the cause.
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Rose Fragrance is likely, phenoxyethanol, Caps. It can be something you have been using for a while without problems. Good luck
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Its seem amodimethicone, its build up
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@Syl @ariepfadli thanks.
I i did check preservative and surfactants at currently amount and ratio and the problem was not there. I will check the rose fragrance oil tomorrow and the remaining ingredients after that.I feel too that Amodimethicone had caused buildup.
I did use it at 2.5%(0.75% active Amodimethicone). What percentage du you suggest for it to not cause buildup? Or it is going to cause buildup anyway in any percentage?Does only buildup of Amodimethicone cause irritation or any silicone and polymer?
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I just add 0.2-0.5 if its full amodimethicone , or up to 2 % if its emulsion with active 30%, its always cause build up onhair, but most annoying if its build up on your head skin
You need to refresh your hair each week with sles shampoo, without any silicone in their ingredient to remove build up -
@ariepfadli thanks for the information.
when i think deeply i can’t understand why and how this buildup from Shampoo ingredients happens and what ingredients can cause buildup and how.
As i know in theory ingredients remain in hair by two mechanism. Having positive charge and dilution/deposition.
If Amodimethicone or cationic guar or PQ10 attach to hair because of the cationic charge then when all the negative charges from hair surface are saturated with these ingredients and there is no more negative chare, why more of these ingredients get attached to hair and cause buildup?
If they stay in hair by dilution/disposition mechanism and not their positive charge then why other ingredients like xanthan gum or regular guar gum don’t stay on hair and cause buildup from Shampoo?
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Cationic side, yes by ionic interaction, but hydrophobic side, build up with another hydrophobic side van der walls interaction, and collection another hydrophobic part , make you hair seem slightly tacky, just try with lower concentration amodimethicone you will feel what i mean
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@Abdullah Even though Amodimethicone and Guar/PQ-10 have cationic charge, they deposit through different mechanisms. Guar and PQ’s form a coacervate with the anionic surfactants, and it’s this neutral complex that deposits on hair in an uneven way (during dilution), and that’s why these materials thend to build-up on hair. Amodimethicone on the other hand deposits in an even way, so once a layer it’s formed, it’ll repel any additional Amodimethicone due to repulsive (cationic-cationic) interaction.
I do believe the anionics (ang glucosides) you have in your formulas are more likely to cause the irritation, since they are actually used (especially the anionics) to denature proteins.
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@ariepfadli thanks. Very good explanation for Amodimethicone.
Now i see why when i washed my hair with only surfactants and preservative to find the irritation cause, my hair felt better 😃. That may be because the load of Amodimethicone was removed from my hair because i have used it for several months in shampoo.Now how does polymers like guar Hydroxypropyltrimonium Chloride cause buildup in hair? This one doesn’t have hydrophobic side.
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@ketchito if cationic guar makes neutral complex with anionic surfactant and deposit this way, does regular guar gum which is also neutral deposit in hair this way and cause buildup?
Does buildup happens because of uneven deposition or because of regular deposition on top of each other?
i have used anionic surfactant in different percentages with other surfactants from 1% anionic up to 12%. In my experience if the anionic surfactant is less than 10% i need to use more shampoo and still the hair doesn’t feel clean or good as high anionic no mater what amount of other surfactants i use.
I will make a sample with half that non-ionic surfactant and see how it works. -
SleS and SLS are both very strong surfactants and they both have high pH which may be bothering your scalp.
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@linne1gi - When you formulate a shampoo with SLS or SLES the pH is typically adjusted such that it is around pH 5.0 - 5.5. It is not particularly problematic for skin. In fact, the SLS in that formula is pretty low. I think the bigger problem is the glucosides which can cause allergic reactions or irritation.
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@Abdullah Keep in mind that guar gum, unlike cationic guar gum, is not positively charged, so it doesn’t have that driving force for deposition, only the molecular wight.
Build-up from coacervates happen due to both overdeposition of the coacervate, and how difficult it is to remove it completely from hair, even for stronger surfactants.
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Thank Perry and Ketchito
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