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  • Q: How can I get started using the YUKO Hair Straightening system?
    A: In order to begin, we will first need a copy of your cosmetology license and you must purchase our starter kit. The starter kit includes 2 sets of straightening solutions, our YUKO pre treatments, tools, shampoo, treatment and hair styling product.
  • Q: What is the main active ingredient in YUKO hair straightening solutions?
    A: The main active ingredient used in YUKO hair straightening solutions is Ammonium Thioglycolate, or “Thio.” Thio works by physically changing the structure of the hair through the application of heat from a flat iron.
  • Q: Is Ammonium Thioglycolate safe?
    A: The safety of Ammonium Thioglycolate has been assessed by the Cosmetics Ingredient Review (CIR) Expert Panel, “Ammonium Thioglycolate is safe for use in hair straighteners, permanent waves, hair styling products…at concentrations up to 15.2%.” YUKO Hair Straightening solutions contain a concentration of less than 10%, as documented in our Material Safety Data Sheet.
  • Q: Do YUKO solutions contain Formaldehyde or any carcinogens?
    A: No. YUKO solutions do not contain Formaldehyde or any carcinogens (cancer-causing substances.) The CIR Expert Panel assessed that cosmetic products should not exceed 0.2% concentration of Formaldehyde. Getting treatments done that use carcinogens over this set standard can cause airway irritation, allergic-type reactions, and, in worse cases, can possibly lead to leukemia, according to studies done by the National Cancer Institute and American Cancer Society.
  • Q: How is YUKO Japanese hair straightening different from Brazilian treatment methods?
    A: YUKO Japanese hair straightening permanently straightens hair by physically changing the internal structure of hair. Brazilian/Keratin treatments temporarily coat hair with keratin to smooth hair. Brazilian/Keratin treatments will wash out after an average of 3 months, so you must visit a salon often to re-coat the hair with this method. Brazilian/Keratin treatments may contain hazardous chemicals which release highly carcinogenic gas. For more information on the danger of chemicals, please check OSHA Safety and Regulations.
  • Q: How is YUKO Japanese hair straightening different from other Japanese hair straightening methods?
    A: In addition to being a state-of-the-art hair straightening system, YUKO hair straightening is also a recognized technique of restoring health to the hair. The YUKO Hair Straightening procedure holds a patent in the US, as well as in Japan, New Zealand, Turkey and other countries.
  • Q: What are some points I should be careful of to get the desired results of YUKO hair straightening?
    A: When shampooing, make sure to remove the excess build up on the surface of the hair before applying solution. Apply appropriate amount of Pre-Treatment. Pre-Treatment will help chemicals to penetrate the hair more evenly and effectively. Use enough solution so hair is saturated. This will help shorten the processing time. Check the temperature of the room before and during the chemical process (processing time is longer in cooler ambient temperature).
  • Q: Can I have YUKO hair straightening and color at the same time?
    A: No. Color clients’ hair at least 2 weeks before or after the straightening procedure. Applying both chemical treatments simultaneously will result in hair damage, so do them separately to avoid undesirable results.
  • Q: Can I do YUKO hair straightening over hair that has a different brand of Japanese hair straightening?
    A: If the previous hair straightening procedure uses the same chemical (Ammonium Thioglycolate) as YUKO straightening solutions, applying YUKO will not be a problem. Please contact both companies to make sure chemicals are the same. Even if both uses same chemicals, the YUKO hair straightening process may not fully work if the hair is badly damaged already.
  • Q: Can I do YUKO hair straightening over hair that has relaxer/Brazilian/Keratin Treatment?
    A: No. We do not recommend doing YUKO hair straightening except on new growth. Please wait 3-4 months until the relaxer/Brazilian/Keratin Treatment coating is completely off clients’ hair to do YUKO hair straightening.
  • Q: What does the YUKO pre treatments do?
    A: The pre-treatments are a unique system specifically designed for hair straightening and hair color. Applying the pre treatments before the straightening procedure adds moisture, protein and keratin to prepare the hair for even straightening results. Give your client straightening and Deep Conditioning Treatment at same time – you will see a marked difference in the end result.
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