The influence of yarn parameters on the ultraviolet protection of yarns

 Improving ultraviolet (UV) protection of textiles is essential to protect wearers against UV radiation induced risks. In addition to fabric parameters, yarn parameters are important factors affecting UV protection of textiles. This work is to examine the influence of yarn parameters on UV protection in order to set up a statistical model for predicting the UV protection of yarns. Wool yarns with different variables were used to test the ultraviolet protection factor (UPF) values for data analysis and the model verification. The model provides the optimized parameters for the UV protective fabric design. This work is helpful as a pre-cursor to the development of a more advanced optical model, which will look at understanding the penetration of UV light through fibres, yarns and fabrics.

Effects of fibre parameters on the ultraviolet protection of fibre assemblies

Ultraviolet (UV) radiation protection is becoming increasingly necessary for human health, and textiles play an important role. The interaction between UV light and textiles is a complex one, involving fibre, yarn and fabric parameters. In this study, an optical model is presented for examining the influences of fibre parameters on the UV protection offered by a bundle of fibres with a given mass. The effects of mean fibre diameter and fibre type on UV absorption were examined. The model was verified with results of UV–visible diffuse reflectance measurements on natural and synthetic fibres. When the mass of fibres was kept constant, within the measurement range in this study, a bundle of fibres with coarser fibres had a lower UV reflectance than that with finer ones. The model accurately predicted factors influencing UV protection, including fibre diameter, fibre transmittance, porosity and refractive index.

UV protection performance of textiles affected by fiber cross-sectional shape

Abstract
In this study, a model was set up for simulating the effects of varying fiber cross-sectional shapes on ultraviolet protection of fibers. The fiber diameter and fiber type were also involved in the model setting. Experiments of diffuse reflectance spectra measurement on natural (wool, cotton, silk), regenerated (bamboo viscose) and synthetic (polyester, nylon) fibers were conducted to verify the model predicted results. When a more complex shape was assumed as the fiber cross-section for model calculation, the predicted results have a better agreement with the actual results. The effects on ultraviolet absorption from fibers with different cross-sectional shapes were investigated at a single fiber, fiber bundle and yarn levels. With the same material, when the fiber cross-sectional area and the areal coverage of a single fiber were constant, the triangular shape had the lowest ultraviolet transmittance and the highest ultraviolet reflectance for a single fiber and also for a fiber bundle. The difference of fiber cross-sectional shapes was also significant in the ultraviolet protection of a single yarn.

Research on the influence of yarn parameters on the ultraviolet protection of yarns

Considering both the yarn parameters and the light interaction (reflectance and transmittance) between two adjacent yarns, an optical model was presented to understand the ultraviolet (UV) light penetrating a single undyed yarn and a lot of yarns. The optical model was verified with results of diffuse reflectance spectra measurement on wool yarn samples. This optical model was used to predict the factors influencing UV protection, including fibre diameter, yarn linear density, yarn twist, transmittance index and refractive index. The statistical predictive model was also set up to show the relationship between the yarn parameters and the UV protection (UPF values) of the yarns. Yarns with the fine diameter, large yarn linear density and low yarn twist had the high UV protection.

Oceanic protection of prebiotic organic compounds from UV radiation

It is frequently stated that UV light would cause massive destruction of prebiotic organic compounds because of the absence of an ozone layer. The elevated UV flux of the early sun compounds this problem. This applies to organic compounds of both terrestrial and extraterrestrial origin. Attempts to deal with this problem generally involve atmospheric absorbers. We show here that prebiotic organic polymers as well as several inorganic compounds are sufficient to protect oceanic organic molecules from UV degradation. This aqueous protection is in addition to any atmospheric UV absorbers and should be a ubiquitous planetary phenomenon serving to increase the size of planetary habitable zones.

Barrier textiles for protection against microbes

The presence or growth of microbes on textiles may result in a series of problems such as unpleasant odors, cross infection, disease transmission, or discoloration and deterioration of textiles. Imparting textiles with antimicrobial property can effectively eliminate these adversities and thus has been attracting great attention. This chapter summarizes the commonly used antimicrobial agents such as silver, metal oxides, photoactive dyes, quaternary ammonium compounds, N-halamines, triclosan, polybiguanides, chitosan, and plant-derived bioactive agents, their characteristics, toxicity, antimicrobial ability, ecological acceptability, and related textile finishing techniques and evaluation methods. Since durability to repeated washing is the major challenge for the practical use of antimicrobial textiles, the chapter provides details on the technique to immobilize antimicrobial agents onto fibers. In addition, impacts of using antimicrobial textiles on the environment and health are discussed in the last section.

Protection of silica-coated ZnO nanoparticles on pre-dyed polyester fabrics against photofading

This work was designed to investigate the ability of silica-coated ZnO (ZnO&SiO2) nanoparticles (NPs) as ultraviolet (UV) absorbers for protecting pre-dyed polyester fabrics against photofading. Despite that ZnO NPs are excellent UV absorbers, their strong photocatalytic activity limits the application in UV protection. In this study, a silica layer was coated onto ZnO NPs to form a physical barrier between the ZnO and a polyester substrate, which allowed effective UV shielding while minimising the harmful effects of photocatalytic activity on the substrate. The structure and optical proprieties of ZnO&SiO2 NPs were observed. The bare ZnO and ZnO&SiO2 NPs were, respectively, applied to polyester fabrics coloured with three kinds of dyes by a dip coating method. The photofading level of treated fabrics after exposure under simulated sunlight was evaluated. The ZnO&SiO2 NPs exhibited excellent protection on pre-dyed polyester fabrics against photofading.

Changes in skin protection behaviors, attitudes, and sunburn: In a population with the highest incidence of skin cancer in the world

This study describes changes in skin protection attitudes and outdoor behaviors of adults in Queensland, Australia, using two cross-sectional telephone surveys conducted in 1988/89 (N = 1699) and 1991/92 (N = 2317). After adjustment for potential confounders, there were significant improvements in some skin protection attitudes, time spent outside, hat wearing, sunscreen use, overall skin protection (p < 0.01) and shade use (p < 0.05) between 11:00 AM and 3:00 PM on the previous Sunday. The degree of attitudinal and behavioral change varied with age, gender, region, and reported skin type. However, recent sunburn experience remained unchanged. A similar study in Victoria, Australia, observed changes in skin protection attitudes, behaviors, and recent sunburn. We speculate on possible explanations for the lack of improvement in recent sunburn experience despite the improvement in skin protection attitudes, and behaviors, and suggest that part of the explanation may be environmental differences. This has implications for generalizability of such studies outside the geographical region in which they were conducted. Article in Cancer Detection and Prevention 20(6):566-75 · January 1996

Misunderstanding or Misdirection?: Whistleblower Protection in Queensland

In his report into corruption in Queensland, Fitzgerald listed whistleblower protection as a necessary part of a strong governance regime. "What is required is an accessible, independent body to which disclosures can be made, confidentially (at least in the first instance) and in any event free from fear of reprisals." It was one of the reforms studied by the Electoral and Administrative Review Committee, the report of which resulted in the Whistleblowers Protection Act 1994 (WPA). The need for whistleblower protection was supported by all sides of Parliament. The Premier, Wayne Goss, in his Second Reading Speech on the Public Sector Ethics Bill , said that that Act and the WPA would form a package with the former outlining required behaviour and the WPA encouraging staff to report wrongdoing. The WPA was subsequently passed and has remained virtually unamended for over a decade. Such consistency is either an indication of skilled drafting and effectiveness or the fact that the Act has been neglected. It is the hypothesis of this paper that the latter is the case. This hypothesis will be tested by examining the sincerity and diligence with which the Act has been treated during, and following, its passage.