Dyeing Performance and Anti-Superbacterial Activity of Cotton Fabrics Dyed with Chamaecyparis obtusa .

In hospitals, doctors' and patients' uniforms, as well as bedding and textiles, can be carriers of superbacteria. This study was conducted to test the anti-superbacterial activity of cotton fabrics dyed with extracts of Chamaecyparis obtusa ( C. obtusa ). The dye was extracted by boiling C. obtusa in water. The test cotton was mordant-dyed three times with the solution at a 1:17 dyeing bath ratio and at an 8.69% (o.w.f) dye concentration for 15 min at 40 °C. C. obtusa dyeing demonstrated a high dyeing affinity in the absence of mordant (K/S value = 14.62). The K/S value of the dyed fabric increased in the order of Cu-mordanted, Fe-mordanted, non-mordanted, and Al-mordanted cotton. Dry cleaning, perspiration and rubbing fastness were determined to be good (Grade 4-5). The dyed fabrics appeared to have a high deodorizing ability compared to the control fabric. They showed not only antibacterial activity against Staphylococcus aureus ( S. aureus) and Klebsiella pneumoniae ( K. pneumoniae ), known to be frequently found in fabrics, but also higher antibacterial activity against the superbacteria methicillin-resistant Staphylococcus aureus (MRSA) (reduced by 99.7%). These results suggest that fabric dyed with C. obtusa extract may be used in clothes and bed linens for inpatients, given its high anti-superbacterial activity. Furthermore, such fabrics may contribute to inhibiting pathogenic infections when used in hospital uniforms or operation gowns for doctors or nurses in hospitals.