An essential substance in L'Oréal 's Youth Code or Code of Youth.

Pro-Cysteine, an essential ingredient in L'Oréal's Youth Code, or Code of Youth.

Pro-Cysteine is synthesized by structural modifications of Cysteine, a precursor to the body's production of glutathione.

Pro-Cysteine is currently under a patent of L'Oréal, if used in any cosmetic formula. Please follow the requirements as follows In order not to breach the patent requirements of L'Oréal

1. Cannot claim the action of Pro-Cysteine in whitening, anti-aging, moisturizing can be (patent: L-2-oxothiazolidine-4-carboxylic acid derivatives and use thereof for skincare )

2. I cannot claim that I use a mixture of L'Oréal.

The results of the experiments working in various fields of Pro-Cysteine please check the following link patent: L-2-oxothiazolidine-4-carboxylic acid derivatives and use thereof for skincare

Pro-Cysteine is highly acidic, the formula used requires the use of an alkali to adjust the pH.

If using Pro-Cysteine in a proportion of more than 2%, Sodium Hydroxide is recommended for pH adjustment as it has sufficient alkalinity.

If using Pro-Cysteine in the proportion of 1-2%, Triethanolamine is recommended. To help adjust the pH

Usage: For Whitening, Anti-Aging products in any form

Mixing method: Mix in water and adjust pH using alkali such as Sodium Hydroxide or Triethanolamine Because the mixture is acidic

Rate of use: 1-5% (recommended 1-2%)

Product characteristics: White powder, low pH, high acidity.

Solubility: Can dissolve in water

Storage: Can be stored in the refrigerator Covered from sunlight, heat, the product is at least 2 years old.

INCI Name : L-2-oxothiazolidine-4-carboxylic acid

Examples of products using Pro-Cysteine

Vichy IDÉALIA EYES EYE CONTOUR IDEALIZER

LANCOME BIENFAIT MULTI-VITAL SPF 30 DAY CREAM

LA ROCHE-POSAY Active C10

L'OREAL Youth Code Dark Spot Correcting & Illuminating Serum Corrector