Home Cosmetic Science Talk Formulating Innovation How this color changing hand wash works?

  • How this color changing hand wash works?

    Posted by karlyip on December 16, 2020 at 9:05 am

    I saw a product on this webpage and wondering how this handsoap work

    https://puttyworld.com/collections/hypercolor-foaming-handsoap

    As far as I know, there is no water-soluble color-changing dye on the FDA color additive list. Therefore, it probably just an optical illusion instead of the color change of pigment.

    To prove my assumption is correct, I tried mixing blue food dye with foaming soap and I found the foam color really became paler and close to white when I scrubbing the foam. However, when I tried to add more dye to make it as deep as the ad is shown, the color of the foam is still so deep and doesn’t turn paler with scrubbing. I think that the combination of surfactant might matter, more foam generated might make the foam whiter. In my experiment, I mixed 3.5% of SDS with 4% of CAPB. Is there any combination of surfactant could generate more white foam? Is decyl glucoside with CAPB a good combination? Thank you. 

    Bill_Toge replied 3 years, 11 months ago 7 Members · 16 Replies
  • 16 Replies
  • MarkBroussard

    Member
    December 16, 2020 at 11:37 pm

    Ha! … It’s a really cool idea to get children to wash their hands for a long enough period of time.

    Do you happen to have a list of ingredients?

  • karlyip

    Member
    December 17, 2020 at 3:30 am

    Ha! … It’s a really cool idea to get children to wash their hands for a long enough period of time.

    Do you happen to have a list of ingredients?

    Hi Sir, I don’t have it in my hand…

  • MarkBroussard

    Member
    December 17, 2020 at 3:32 am

    Without the list of ingredients, it is not possible to get any insight into how they may have achieved this effect.

  • jemolian

    Member
    December 17, 2020 at 7:44 am

    Looking at the website, the marketing message mentions Hypercolor technology? The color seems to change to white due to heat. 

    https://en.wikipedia.org/wiki/Hypercolor

  • AuroraBorealis

    Member
    December 18, 2020 at 12:28 am

    My guess is something encapsulated. Reminds me of the color changing toothpastes for kids. 

  • karlyip

    Member
    December 18, 2020 at 9:01 am

    jemolian said:

    Looking at the website, the marketing message mentions Hypercolor technology? The color seems to change to white due to heat. 

    https://en.wikipedia.org/wiki/Hypercolor

    I also thought about that kind of technology.
    I had gone through the EPA regulation and found that should not be utilized in this kind of product. My friend told me that the hypercolor actually is kind of very small particle and I’m not sure it can pass through the mesh of the foaming dispenser without clotting it. 

  • karlyip

    Member
    December 18, 2020 at 9:04 am

    My guess is something encapsulated. Reminds me of the color changing toothpastes for kids. 

    I am still wondering is there any foaming dispenser allowing the microcapsule passing through without clotting it?

  • jemolian

    Member
    December 18, 2020 at 9:15 am

    I guess the only way is to look at the ingredients list if any is available online or i guess someone will have to look at it in stores or purchase it. Makes me curious as well. 

    I’m assuming the Itzazu® Color Changing Hand Soap is similar but the actives are encapsulated in a bead form? 

    https://www.tropicalseas.com/products/itzazu-color-changing-hand-soap

  • karlyip

    Member
    December 18, 2020 at 9:22 am

    jemolian said:

    I guess the only way is to look at the ingredients list if any is available online or i guess someone will have to look at it in stores or purchase it. Makes me curious as well. 

    I’m assuming the Itzazu® Color Changing Hand Soap is similar but the actives are encapsulated in a bead form? 

    https://www.tropicalseas.com/products/itzazu-color-changing-hand-soap

    Yea, I also saw that on the internet, it obviously contains some pigment beads but I’m not sure if we can apply it into a foam soap

  • karlyip

    Member
    December 22, 2020 at 6:42 am

    Without the list of ingredients, it is not possible to get any insight into how they may have achieved this effect.


    I finally found the ingredients on the internet! It just playing a trick using optical illusion. However, I can’t make the color as deep as it.  :/

    I tried mixing Decyl Glucoside and SLS in around 1:1 to make it generate more foam by scrubbing action. Pale blue is okay, the foam could turn into nearly white, but it cannot deeper than that kind of pale blue.   :#

  • Bill_Toge

    Member
    December 23, 2020 at 1:08 am
    given that castile soap is alkaline, I’d suspect it’s due to a dye that’s coloured in alkaline conditions and colourless in neutral to acidic conditions; as the soap is lathered more and more, it becomes increasingly diluted and neutralised, therefore losing its colour
    the most likely candidate for the pink variant is phenolphthalein, and the most likely candidate for the blue variant is thymolphthalein
    not sure about the green though, it may well be a mixture of 3-nitrophenol (yellow/red) and thymolphthalein (blue)
    the one that goes from white to blue is almost certainly due to an encapsulated pigment; Daito Kasei, among others, specialise in this kind of technology
  • OldPerry

    Member
    December 23, 2020 at 2:13 pm

    @Bill_Toge - I remember using a lot of phenolphthalein in organic chemistry! Never used it in formulating though.

  • em88

    Member
    December 27, 2020 at 1:28 pm

    There is a small problem with phenolphthalein. It is carcinogenic and it is prohibited in cosmetic products in the EU. 

  • karlyip

    Member
    December 28, 2020 at 2:53 am

    em88 said:

    There is a small problem with phenolphthalein. It is carcinogenic and it is prohibited in cosmetic products in the EU. 

    Yea, it isn’t on the list of FDA-approved pigments list as well, so it is supposed can’t be sold in the US. 

  • karlyip

    Member
    December 28, 2020 at 3:18 am

    Bill_Toge said:

    given that castile soap is alkaline, I’d suspect it’s due to a dye that’s coloured in alkaline conditions and colourless in neutral to acidic conditions; as the soap is lathered more and more, it becomes increasingly diluted and neutralised, therefore losing its colour
    the most likely candidate for the pink variant is phenolphthalein, and the most likely candidate for the blue variant is thymolphthalein
    not sure about the green though, it may well be a mixture of 3-nitrophenol (yellow/red) and thymolphthalein (blue)
    the one that goes from white to blue is almost certainly due to an encapsulated pigment; Daito Kasei, among others, specialise in this kind of technology

    I searched pigments you mentioned on the ECHA, it seems that none of them could be used in rising products… I still believe that they use some optical trick like you described, as the soap is lathered more and more, the pigment becomes diluted and nearly invisible. 

    BTW, I found another foaming hand wash claiming “color-changing” in Japan. 

    https://pop.inquirer.net/88723/this-pokemon-themed-hand-soap-changes-its-color-everytime-you-wash-your-hands

    Actually, I got one in hand and found the blue color is… very pale at all and hardly found any color change after lathering… 

    I also noticed that, in both AD, they all show the color changing effect of the purple or reddish foam rather than blue foam… I think purple and red are “warmer” than blue, so it can easily create an illusion when it turns very very pale, conceiving the user that the foam turned into white. But for blue, we can still recognize it when it turns very very pale after lathering, so the color changing effect is not good at all. 

    https://pop.inquirer.net/88723/this-pokemon-themed-hand-soap-changes-its-color-everytime-you-wash-your-hands 

    Please correct me if I have something incorrect. 

  • Bill_Toge

    Member
    January 8, 2021 at 4:54 pm

    the fact it’s not permitted won’t stop an unscrupulous brander from using it anyway

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