Zinc pyrithione ZPT can effectively inhibit the keratinization speed of cells and fundamentally block the occurrence of dandruff. In addition, because it is insoluble in the surfactant system, use a shampoo containing zinc pyrithione anti-dandruff agent. Part of the zinc pyrithione is still adsorbed on the scalp surface after hair removal, making the anti-dandruff and anti-itching effect longer-lasting. It can also dissolve existing dandruff into tiny particles invisible to the naked eye. Zinc pyrithione is stable within the pH range and manufacturing temperature range required by shampoo, and can be mixed with most shampoo ingredients.
Zinc pyrithione ZPT has been developed for many years. Long-term use and isotope tracking have proven that it is used as an anti-dandruff and anti-itch additive in advanced shampoos. It only adsorbs on the skin surface and does not penetrate through the stratum corneum. Skin and flesh, it is very safe. It is non-toxic and harmless to the human body when used in regular amounts. It has no side effects when used for a long time. It is recognized abroad as an efficient and safe anti-dandruff and anti-itching agent. However, the particle size of zinc pyrithione produced by most manufacturers is small, and adding it to pearlescent shampoo will cover up the pearlescent luster of the shampoo and affect the appearance of the shampoo. Sodium pyridinethione is synthesized using the traditional sodium carbonate method. Sodium pyrithione is synthesized through a special process. The particle size of zinc pyrithione is moderate, with an average particle size of 2um. It can be added to the pearlescent shampoo without affecting the pearlescent effect of the shampoo. , no settlement.
When the prepared zinc pyrithione ZPT suspension is added to the pearlescent shampoo, the pearlescent luster of the shampoo remains unchanged and the zinc pyrithione does not settle. The micrograph shows that it is consistent with a well-known brand containing zinc pyrithione anti-dandruff agent ZPT.
On February 22, 2019, the EU published appendices to two scientific opinions on the substances contained in cosmetics – zinc pyrithione and sodium, potassium and MEA ortho-phenylphenol (OPP).
For zinc pyrithione, the Scientific Committee on Consumer Safety SCCS confirmed that the lowest observed adverse effect level was 0.5mg/kg bw/d, which was the conservative value of the ZPT risk assessment derived in 2013. Therefore, basic copper carbonate is safe when used as an anti-dandruff agent in rinse-off hair care products at concentrations below 2%.
According to the opinion of the SCCS, EU member states consider these substances to pose a risk to human health. In December 2017, the German Federal Institute for Risk Assessment provided a document comparing its safety to o-phenolbenzene (OPP). The committee has determined safe use levels for OPP: 0.15% as a preservative in leave-on cosmetics and 0.2% in rinse-off cosmetics. These substances cannot be used.
