Influence of Optical Brightening Agent Concentration on Properties of Cotton Fabric Coated with Photochromic Microcapsules Using a Pad-Dry-Cure Process

The weak photostability of photochromic dyes applied to textile substrates is one of the disadvantages of the broader use of photochromic dyes in the textile industry. Therefore, the influence of optical brightener concentration on both the photocoloration and photostability of cotton fabric coated with photochromic microcapsules using a pad-dry-cure process, as well as the physical-mechanical properties and colorfastness properties, were studied in this research. Coated samples were subjected to different tests according to valid EN ISO standards; namely mass per unit area, fabric stiffness, breaking force and elongation, air permeability, and different colorfastness properties (rubbing, domestic and commercial laundering, and light). Results showed that the coated fabric had higher mass per unit area, stiffness, breaking force and elongation and lower air permeability compared to uncoated fabric, irrespective of the padding bath composition. Coated fabric has better colorfastness to wet than dry rubbing. The colorfastness to washing decreases with the increased number of washing cycles. The use of optical brightener decreases the photocoloration of coated fabric and increases the photostability of coated fabric after the exposure of samples to a Xenotest apparatus for longer than 12 h.

Preparation and Properties of Chitosan/Graphene Modified Bamboo Fiber Fabrics

Chitosan (CS) and graphene (Gr) were used to modify bamboo fiber fabrics to develop new bamboo fiber fabrics (CGBFs) with antimicrobial properties. The CGBFs were prepared by chemical crosslinking with CS as binder assistant and Gr as functional finishing agent. The method of firmly attaching the CS/Gr to bamboo fiber fabrics was explored. On the basis of the constant amount of CS, the best impregnation modification scheme was determined by changing the amount of Gr and evaluating the properties of the CS/Gr modified bamboo fiber fabrics. The results showed that the antibacterial rate of CGBFs with 0.3 wt% Gr was more than 99%, and compared with the control sample, the maximum tensile strength of CGBF increased by 1% in the longitudinal direction and 7.8% in the weft direction. The elongation at break increased by 2.2% in longitude and 57.3% in latitude. After 20 times of washing with WOB (without optical brightener) detergent solution, the antimicrobial rate can still be more than 70%. Therefore, these newly CS/Gr modified bamboo fiber fabrics hold great promise for antibacterial application in home decoration and clothing textiles.

Concept Evaluation of Predicting UPF Values for Artificial Cellulose Fabrics by Varying the Optical Brightener Chemical Structure Applied

The publication presents investigation results and statistical analysis showing that by varying the chemical structure of optical brighteners from the derivative group of stilbene used for fabrics of artificial cellulose fibre modification, resulting in a different manufacturing process, it is possible to predict the level of the UPF value of the index of such modified fabric. In addition, statistically it was confirmed by results from early research that both the fibre finish (in this case, roughening the pigment TiO2 ) used for fabric manufacture as well as the FBA concentration used for fabric modification influence their UPF index value. Fabric UV -barrier studies also showed that despite a partial decrease in UPF values for such finished fabrics, the dependence of such an index on subtle differences in the chemical structure of the FBAs is maintained. Primarily the possibility and range of improving textile barriers against UV radiation through the use of the UV-absorption abilities of optical brighteners with subtle differences in their chemical structure was recognised, creating a premise to elaborate a mathematical control concept to steer a textile UV-barrier.

Associations between fecal indicator bacteria prevalence and demographic data in private water supplies in Virginia

Over 1.7 million Virginians rely on private water sources to provide household water. The heaviest reliance on these systems occurs in rural areas, which are often underserved with respect to available financial resources and access to environmental health education. This study aimed to identify potential associations between concentrations of fecal indicator bacteria (FIB) (coliforms, Escherichia coli) in over 800 samples collected at the point-of-use from homes with private water supply systems and homeowner-provided demographic data (household income and education). Of the 828 samples tested, 349 (42%) of samples tested positive for total coliform and 55 (6.6%) tested positive for E. coli. Source tracking efforts targeting optical brightener concentrations via fluorometry and the presence of a human-specific Bacteroides marker via quantitative real-time polymerase chain reaction (qPCR) suggest possible contamination from human septage in over 20 samples. Statistical methods implied that household income has an association with the proportion of samples positive for total coliform, though the relationship between education level and FIB is less clear. Further exploration of links between demographic data and private water quality will be helpful in building effective strategies to improve rural drinking water quality.