COSMETICS & PERSONAL CARE
Figure 2 – Mechanism of antibacterial action
Microbiology & Infectious Diseases at Nara Medical University showed that it inactivated SARS-CoV-2 , the virus that causes COVID-19 , by 99 % at a treatment time of 60 minutes and 99.9 % at 120 minutes , with a polymer concentration of 0.1 % ( Figure 1 ). In addition , the new polymer shows good antibacterial performance against a variety of microorganisms . It outperformed the conventional antibacterial agents methylparaben and phenoxyethanol when used against the environmental bacteria E . coli , S . aureus and P . aeruginosa ( Table 1 ). Tests also showed it to have good activity against C . acnes and M . furfur . According to antibacterial tests , the polymer has a broad-range antibacterial spectrum and the mechanism of both antibacterial and antiviral action was considered to express itself by disrupting the cell membranes ( Figure 2 ). The polymer is expected to keep the surface of both skin and hair cleaner . The new polymer also has an adhesion prevention effect on fine particles . We tested adhesion of false pollen ( Lycopodium powder ) to the surface of polyurethane and
of a surface covered by this polymer and found the adhesion rate for the polymer was 54 % lower ( Figure 2 ). Its adhesion prevention effect on false PM2.5 was also confirmed . Tests were also carried out on the effect of the multi-functional polymer on the water content of the stratum corneum before and after application . First , the multi-functional polymer was applied to the skin , then it was rinsed off . The measurement was completed 60 minutes later . The water content increased by about 30 %, suggests that the new polymer has an excellent moisture retention effect . It is thus expected to enhance the skin barrier function . Cosmetics containing this polymer are also expected to protect the skin and hair from the damage and improve skin conditions .
Conclusion
The human skin covering the outer layer of human body has an important role as skin barrier against external factors such as viruses , microorganisms , pollen , PM2.5 , etc . These external factors have affected the variety of human health .
Therefore , it is important to keep the skin healthy . If the adhesion of external factors to the skin is prevented and skin barrier properties are enhanced , skin trouble can be prevented . So , we believe that one of the solutions for leading a healthy lifestyle is to protect the skin against external factors by cosmetics containing this multi-functional polymer . •
Tadayoshi Nomura
MANAGER , COSMETICS BUSINESS OFFICE
NIPPON SHOKUBAI CO ., LTD . k + 81-6-6223-9252 J tadayoshi _ nomura @ shokubai . co . jp j www . shokubai . co . jp / en /
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