What Are the Results of Comparing Two Different Dyeing Shampoos Based on Dyeing Principles?

Chung-Ang University Hospital Professors Kim Beomjun and Seokjun Research Team
Comparison of Modamoda and Amorepacific Products
"Confirmed Advantages and Disadvantages of Browning and Coating Methods"

A study comparing 'coloring shampoos' developed to reduce the hassle of hair dyeing according to their coloring principles has drawn attention. In conclusion, each has its own advantages and disadvantages.

The research team led by Professors Kim Beom-jun and Seok Jun from the Department of Dermatology at Chung-Ang University Hospital recently announced on the 28th that they published a research paper in an international journal comparing the coloring effects and impacts on hair of two coloring shampoos with different coloring principles.

Professor Beomjun Kim (left) and Professor Seokjun at the Department of Dermatology, Chung-Ang University Hospital.

The team compared two shampoos: Modamoda's 'Pro Change Black Shampoo,' which uses a browning method, and Amorepacific's 'Ryeo Double Effector Black Shampoo,' which uses a coating method. The Modamoda product contains patented polyphenol ingredients that react with oxygen and sunlight to gradually turn gray hair into dark brown, while the Amorepacific product uses a patented gray hair cover ingredient that accumulates coating on the hair to provide a gray hair cover effect.

To evaluate the effects of the two coloring shampoos, the research team measured changes in hair brightness, color retention, strength, softness, elasticity, gloss, moisture content, protein content, and hair structure after 10 washes with each shampoo.

In the case of the coating method shampoo, it dyed hair darker compared to the browning method shampoo and reduced the lifting phenomenon between hair cuticles, improving hair roughness. Professor Seok explained, "The cuticle is a scale-like layer on the surface of the hair that protects hair from physical and chemical stimuli to prevent damage, playing an important role in hair damage levels," adding, "Hair tensile strength, gloss, and elasticity showed similar effects in both types of shampoos."

Modamoda 'Pro Change Black Shampoo' (left), Amorepacific 'Ryo Double Effector Black Shampoo' [Image source=each company]

Meanwhile, the browning method shampoo was found to increase the 'hydroxyl radical' in hair more than the coating method shampoo. Hydroxyl radicals are reactive oxygen species generated by external factors such as ultraviolet rays and fine dust, as well as aging, inducing oxidative stress. Reactive oxygen species are known to cause damage to skin cells and tissues and can weaken the skin's defense system.

Professor Seok stated, "Both shampoos with different coloring principles are expected to maintain gray hair coverage well with continuous use, but it is also necessary to consider that hair damage may vary with long-term use depending on the coloring method or principle," adding, "The coating method shampoo improved hair coloring effects and roughness, while the browning method shampoo may have the advantage of longer color retention but showed some indicators of potential damage to the hair cuticle protective layer."

Additionally, Professor Kim said, "Through this study, we confirmed the different pros and cons of the browning method shampoo and the coating method shampoo according to their coloring principles," and added, "In the future, various studies and long-term clinical research will be necessary not only to verify the efficacy of newly developed hair color shampoos but also to conduct long-term repeated clinical studies related to safety issues such as allergies, scalp itching, and hair damage."

This study was published in the latest issue of the SCIE-level international journal Skin Research and Technology.