Gray scale image analysis was used to investigate visual relaxation behavior of randomly wrinkled cloths including wrinkles like ripple and irregularly folded creases. Randomly and irregularly wrinkled plain cloths of acetate, polyester, cotton, flax, wool and silk were formed by firstly grasping in both hands, after then by applying a load of 5kgf for 30 min. Images of randomly wrinkled cloths were measured in the fixed every time using color scanner. The contrast, correlation and entropy extracted from the gray level co-occurrence matrix were measured as visual feature parameters. The fractal dimension was determined from the fractal analysis of the relief of the curved surface of the gray level image. These image information parameters were found to be useful for characterizing the visual recovery of randomly wrinkled cloths. A parameter ratio was calculated by dividing an image information parameter at some time by one at time zero. Most of parameter ratios decreased more or less exponentially with the increase of time. A parameter of visual wrinkle recovery index was obtained to describe the visual relaxation behavior of wrinkle recovery from the analogy of mechanical stress relaxation behavior. The evaluation for visual recovery of randomly wrinkled cloths was established in this study.
The detergency of the mixture of dodecyl sulfate (SDS) and hexadecyl trimethylammonium bromide (HTAB) was studied using cotton and polyester fabrics. The critical micelle concentration (cmc) of the mixture of mixing ratio 1 : 1 determined by surface tension method was 1×10-4 mol/dm3. Removal of polystyrene latex particles and sterilization of staphylococcus were examined through SEM observation and culture testing. The effect of the mixing ratio of the surfactants on the detergency was investigated. At mixing ratio of about 1 : 1, the removal efficiency of particles had the maximum, and the minimum surface tension of the solution was achieved. This removal efficiency was lager than that at cmc of SDS and HTAB considerably. Sterilization increased with HTAB mixing ratio in the range of the mixing ratio below 0.5 and it was 100% at HTAB mixing ratio more than 0.6. These results suggested the existence of free HTAB molecules in the mixture. The cmc of the mixture was 1/160 and 1/20 of the one for SDS and HTAB respectively.
Shirting fabrics were treated with green tea and tourmaline and their antibacterial activities against Staphylococcus aureus and generating behavior of negative ions were investigated. The boiled down liquid of dry green tea was diluted 4- and 8-fold, A liquid and B liquid, to be used for dyeing. The number of the colonies of Staphylococcus aureus and the generated negative ions were counted after the cloths dyed with A liquid and B liquid were treated with tourmaline and by heating at two different temperatures (80-90℃, 145-155℃). The number of the colonies and the negative ions increased with concentration of tourmaline. The thermal treatment at higher temperature promoted higher generation of negative ions. The cloths treated with not more than 0.2 % of tourmaline after dyeing A and B liquid and the ones only dyed with B liquid almost came up to the standard of bacteriostatic activity of 2.2. It is concluded that these experimental conditions are applicable to clothing life.