High Ultraviolet Protection Factor Research Articles

Dyeing of Cotton and Wool Fibers with the Aqueous Extract of Alnus glutinosa: Evaluation of Their Ultraviolet Protection Factor, Their Color fastness and the Antioxidant Activity of the Aqueous Extract

The aim of the present study is to evaluate the dyeing properties and behavior of the aqueous extract of Alnus glutinosa leaves when applied on cotton and wool fibers. The antioxidant activity and the total phenolic content of the aqueous extract were calculated. The colorfastness of the dyed samples such as washing, acid and alkali perspiration, wet and dry fastness and light fastness was performed. The ultraviolet protection factor (UPF) which is a measurement of the protection offered by the dyed fabric substrates against ultraviolet radiation was also assessed. It was found that Alnus glutinosa aqueous extract shows exceptionally high antioxidant activity and high phenolic content. The dyed samples showed astonishingly high light fastness approaching the light fastness of synthetic dyes such as the vat dyes or metal complex dyes. The conferred protection of the dyed samples against the distractive ultraviolet radiation is exceptionally high as this is demonstrated by the high UPF measurements of the dyed samples.

Combination of bio-based tannic acid, sophora flower extract and metal salts: A facile route towards improving durable flame retardancy and UV resistance of silk fabrics

Environmental engineering placed green demands on the functional modification of textiles. Here, the combination of bio-based tannic acid, sophora flower extract and metal salts was used to manufacture silk fabrics with flame retardancy and UV resistance via a facile impregnation strategy. With different metal salts treated, the modified silk fabrics named silk/TA/SFE-TE, silk/TA/SFE-Fe and silk/TA/SFE-Cu achieved self-extinguishing in the vertical burning test, with limiting oxygen index values of 31.7 ± 0.4 %, 30.2 ± 0.2 % and 30.9 ± 0.3 %, respectively. In the cone calorimetry test, the peak heat release rate values of the three silk fabrics modified with metal salts were all significantly suppressed, and the total smoke production values of silk/TA/SFE-TE and silk/TA/SFE-Fe were reduced from the original 0.178 m2 to 0.126 m2 and 0.138 m2, respectively. Furthermore, silk/TA/SFE-TE, silk/TA/SFE-Fe and silk/TA/SFE-Cu displayed high ultraviolet protection factor values and thus had good UV resistance, owing to the presence of tannic acid and sophora flower extract. Most importantly, the flame retardancy and UV resistance of the three silk fabrics modified with metal salts were still superior to those of the original silk fabrics after 30 washing cycles. In short, this facile route for the preparation of functionalized silk fabrics provides a novel idea for the development of advanced textiles.

Assessment of UV Protection for Children's Summer Clothing.

Excess ultraviolet (UV) radiation exposure during childhood poses a particular long-term risk of developing skin cancer later in life however recent studies have called attention to the absorption of chemical sunscreen ingredients into the bloodstream with unclear significance.This has led to recommendations to consider sun protection in the form of clothing to reduce the need for sunscreen products. Ten brands of routine summer clothing not labeled as sun protective from five distributors marketed for children were identified with varying price ranges.Summer clothing items consisting of T-shirts and tops were evaluated for fiber composition, cost, and UPF testing was performed to determine UVA and UVB transmittance. Results: Around 88.2% of blended textile compositions compared to 60% of 100% cotton textiles offered adequate UV protection with an Ultraviolet Protection Factor (UPF) greater than 15. 58% of blended fabrics compared to 50% of cotton textiles offered a UPF greater than 30. There was no correlation between brand and cost with UPF values. Conclusions: In the absence of regulations for testing and labeling of all children's garments for UV protection, guidelines for the pediatric population for choosing clothing for the summer should reflect the information available to consumers that is easy to understand and more likely to result in higher UPF values.Based on fiber composition, blended textiles are more likely to have adequate UV protection compared to 100% cotton or 100% polyester.

Silica Modified Natural Dye of Caesalpinnia sappan l. on Cotton Fabrics

Sappana (Caesalpinnia sappan L.) has been known as a natural dye in textiles and food. This research aimed to develop a sappan-based natural dye for fabrics dyeing by SiO2 modification as the UV protection agent. The sappan dye and its color were measured by colorimetric methods on UV-Vis spectrophotometry. The testing of the material includes a standard color detection test on the solution and washing resistance on cotton fabrics. The product is the prototype of a stable natural dye product of SiO2 modified - sappan (Si-Cs) which will be performed consistently on cotton fabrics. The result showed that SiO2-modified sappan dye had a higher absorbance in UV-Vis Spectrometer. The performance of the coloring product was also better than the standard sappan dye, indicated by the higher Ultraviolet Protection Factor and the fastness value. Variations of coloring products affected by the mordant agents varied from orange-red-purple caused by non-mordant–alum acetate and iron mordant respectively.

Development of photochromic poly(azobenzene)/PVDF fibers by wet spinning for intelligent textile engineering

Compared to azobenzene (AB) mono-molecule, the as-synthesized AB polymer showed better photochromic ability and chemical resistance. An intelligent fiber with photochromic properties can be successfully developed with the as-synthesized AB polymer and polyvinylidene fluoride (PVDF) via a facile wet spinning process. The doping of AB polymer in intelligent fiber showed little effect on intrinsic properties of PVDF fiber but significantly altered the surface performances like aesthetics, UV sensing and shielding. The intelligent fiber could reversibly change the color from pale yellow to orange red under UV irradiation, conferring a potential to be used as a flexible UV indicator. As a functional embroidery thread on fabric, the photochromic PVDF fiber displayed stable photochromic responses, reversible optical contrast and good photo-coloration kinetics, greatly improving the appearance and functionality of the substrate fabric. Moreover, the fabric knitted with this photochromic fiber could offer UV shielding property verified with the high ultraviolet protection factor. Furthermore, the functional fiber had good resistance to different solvents, thus, it exhibited qualities to be used under harsher conditions. Compared with the extensive research of spiropyrans (SPs) and spirooxazines (SOs) in color-changing textile, this study would be a complementary research for the application of azobenzenes (ABs) in intelligent textiles.

GRAFTING OF BORON-NITROGEN-DOPED CARBON QUANTUM DOTS ON COTTON FABRIC FOR IMPARTING ANTI-ULTRAVIOLET PROPERTIES

"In order to improve the anti-ultraviolet property and laundering durability of cotton fabrics, the cotton fabrics were cationized with epoxy propyl trimethylammonium chloride, and then boron-nitrogen-doped carbon quantum dots (BN-CQDs) were grafted onto the cationized cotton fabrics by the chemical reaction between the quaternary ammonium cation on the cotton fabrics and the carboxyl functional group on the surface of BN-CQDs. The structure, the ultraviolet protection performance and washing durability of the cotton fabrics grafted with BN-CQDs were characterized and tested. The results showed that the resultant cotton fabrics modified with BN-CQDs exhibited a very high ultraviolet protection factor (UPF). Even after 20 consecutive washings, the UPF value was still as high as 75.3, suggesting the promising potential of the modified fabrics as UV protective materials and their excellent laundering durability."

Importance of Protocol Design for Suitable Green In Situ Synthesis of ZnO on Cotton Using Aqueous Extract of Japanese Knotweed Leaves as Reducing Agent

This work presents two protocols for the green in situ synthesis of zinc oxide nanoparticles (ZnO-NP) on cotton with the aim to develop sustainable cotton fabric with an ultraviolet protection factor (UPF). The protocols differed in the order of immersing cotton fabric in reactive solutions of three batches, i.e., precursor (0.1 M zinc acetate dihydrate), reducing agent (aqueous extract of Japanese knotweed leaves) and alkali (wood ash waste). The scanning electron microscope (SEM) results showed that ZnO-NP were successfully synthesised on cotton using both protocols; however, only the protocol where cotton was first immersed in alkali, then in the precursor and, lastly, in the reducing agent enabled very high UPF and higher amount of Zn present on the sample. Due to the different order of cotton fabric immersion in the reactive solutions, dissimilar morphology of the ZnO particles was observed, which resulted in different UV blocking abilities of the samples. The antioxidant analysis (DPPH) showed that the natural reducing agent prepared from Japanese knotweed leaves has very high antioxidant activity, which is attributed to phenolic compounds present in the plant. The reflectance spectroscopy results confirmed that the colour yield and colour of the samples did not influence the UPF value. This protocol is an example of green circular economy where waste materials of invasive alien plant species and pellet heating was used as a natural source of phytochemicals, for the direct synthesis of ZnO-NP to develop cotton fabric with UV-protective properties.

Functionalization of cotton fabric with ZnO nanoparticles and cellulose nanofibrils for ultraviolet protection

A simple impregnation method was employed to obtain functional cotton fabric based on a zinc oxide (ZnO) and cellulose nanocomposite. The cellulose nanofibril suspension was utilized to reduce the agglomeration of ZnO nanoparticles (ZnO NPs) and bind them to the surface of the fiber. Scanning electron microscopy and inductively coupled plasma mass spectrometry were used to confirm the presence of ZnO NPs on the surface of the fiber. The treated cotton fabrics exhibited high ultraviolet protection factor values, which were still higher than 50 even after 30 standard washing cycles. Furthermore, the treated samples showed a modest antibacterial effect due to the presence of ZnO NPs. Meanwhile, the treated cotton fabrics showed a decrease (less than 30%) in air permeability.

A molecularly engineered bioderived polyphosphate for enhanced flame retardant, UV-blocking and mechanical properties of poly(lactic acid)

Polylactic acid (PLA) represents one of most promising bioplastics in response to the increasing global microplastics pollution issue facing the entire ecosystem. Nevertheless, PLA is inherently flammable and also prone to UV-light attack, significantly restricting its wide applications in packaging, fibers and electronics industry. Despite high effectiveness in PLA, existing polyphosphate-based flame retardants are usually synthesized mainly from non-degradable petrochemical compounds and their functions are limited to improving flame retardancy of the polymeric matrix. We, herein, report the synthesis of a novel multifunctional bioderived polyphosphate (PPD) for PLA by using plant-derived diphenolic acid as a starting material. Our results reveal that the addition of 6 wt% of PPD enables PLA to achieve a desirable UL-94V-0 rating and a high LOI value of 27.1% due to its high gas-phase activity, which means that the final PLA fully meets the demanding flame retardancy requirement in industry. Moreover, the resultant flame-retardant PLA shows a high ultraviolet protection factor (UPF) value of 403, which indicates its excellent UV protection capability. Because of the fine and uniform dispersion of PPD within the resin matrix and their strong interfacial interactions, the PLA/6% PPD shows a 31% increase in impact toughness and a slight improvement in tensile strength compared to the bulk PLA. This work provides a strategy to synthesize a multifunctional bio-based polyphosphate flame retardant, which holds great promise for extending the practical applications of PLA with excellent flame retardancy, UV-blocking and mechanical performances.

Intumescent flame‐retardant and ultraviolet‐blocking coating screen‐printed on cotton fabric

Herein, we report an interlayer-confined strategy to intercalating two-dimensional zirconium phosphate (ZrP) within reduced graphene oxide (RGO) interlayers, generating the hierarchical ZrP–RGO hybrids. The hybrids were then blended with ammonium polyphosphate to fabricate an intumescent flame-retardant coating on cotton fabric through an automatic screen printing. The resulting cotton fabric shows an excellent self-extinguishing performance when subjected to a butane flame. During combustion, its peak heat release rate and total heat release are significantly decreased by 92.1% and 61.8% in contrast with control cotton fabric, and a flame-retardant mechanism is reasonably proposed by the condensed and gaseous analysis. Furthermore, the flame-retardant cotton fabric exhibits an excellent ultraviolet-blocking performance with the high ultraviolet protection factor of 201.51. Even after 300 cycles of abrasion, the coated cotton fabric retains the superior flame-retardant and ultraviolet-blocking properties. This work provides a simple and feasible strategy to prepare the multifunctional fabrics.

Rapid synthesis of strawberry microcapsules via Pickering emulsion photopolymerization for use in multifunctional fabric coatings

Multifunctional microcapsules with osmanthus fragrance oil (OFO) as core materials and hexanediol diacrylate (HDDA)/modified titanium dioxide (TiO2) as shell materials were prepared via Pickering emulsion photopolymerization. The microcapsules are strawberry and core-shell structure and then blended with waterborne silicone resin to form multifunctional fabric coatings. The preparation process is rapid and environmentally friendly. The coated fabric can keep fragrance releasing for 85 days at room temperature condition, which showed slow releasing performance of fragrance. Meanwhile, due to perfluorooctyltriethoxysilane and ultraviolet absorbers Tinuvin 1130 grafting on the TiO2 nanoparticles in the shell of microcapsules, the coated fabric not only exhibits excellent superhydrophobicity with high water contact angle (WCA) (158.6°) and low sliding angle (SA) (9.0°), but also possesses Ultraviolet (UV) protection property with high Ultraviolet Protection Factor (UPF) value (210.5).

Enhancing long-term biodegradability and UV-shielding performances of transparent polylactic acid nanocomposite films by adding cellulose nanocrystal-zinc oxide hybrids

We investigated UV-shielding performances and biodegradation abilities under controlled hydrolytic, soil burial, and thermal conditions of transparent polylactic acids (PLA) nanocomposite films embedded with cellulose nanocrystal-zinc oxide (CNC-ZnO) hybrids. By adding high content of 15wt %CNC-ZnO hybrids into the PLA matrix, the highest UV radiation was blocked out by (85.31%) of UV-A and (95.90%) of UV-B. It is found that the weight loss of PLA nanocomposites after being hydrolytic degraded for 70 days increased from 9% for PLA to 25% with 15 wt% CNC-ZnO hybrids. Meanwhile, in soil burial test, pure PLA shows smallest degradation rate with only 8% weight loss after 110 days, while the PLA nanocomposite film with 15 wt% CNC-ZnO hybrids was degraded by about 28%. Besides, the resultant degradation byproducts from the thermally-decomposed catalysis have been identified by Fourier transform infrared spectroscopy (FT-IR). Moreover, the morphologies and appearances changes during the hydrolytic and soil degradation of PLA nanocomposite films were evaluated. This study is expected to provide meaningful insights into nanocomposite films embedded with CNC-ZnO hybrids as a result of contourable degradation and high ultraviolet protection factor value (UPF).

Durable antibacterial and UV-protective Ag/TiO2@ fabrics for sustainable biomedical application.

A facile method was developed to endow cotton fabric with remarkable antibacterial and ultraviolet (UV)-protective properties. The flower-like TiO2 micro-nanoparticles were first deposited onto cotton fabric surface via hydrothermal deposition method. Then, the Ag NPs with a high deposition density were evenly formed onto TiO2@cotton surface by sodium hydroxide solution pretreatment and followed by in situ reduction of ANO3. This work focused on the influence of different hydrothermal reaction durations and the concentration of AgNO3 on antibacterial activity against relevant microorganisms in medicine as well as on the UV-blocking property. Ag NPs-loaded TiO2@cotton exhibited high antibacterial activity with an inhibition rate higher than 99% against Staphylococcus aureus and Escherichia coli bacteria. Moreover, the as-prepared cotton fabric coated with Ag NPs and TiO2 NPs demonstrated outstanding UV protective ability with a high ultraviolet protection factor value of 56.39. Morphological image of the cells revealed a likely loss of viability as a result of the synergistically biocidal effects of TiO2 and Ag on attached bacteria. These results demonstrate a facile and robust synthesis technology for fabricating multifunctional textiles with a promising biocidal activity against common Gram-negative and Gram-positive bacteria.

Influence of yarn folding on UV protection properties of hemp knitted fabrics

In the last years the media have highlighted the damage of the ozone layer and the resulting increase of ultraviolet radiation (UVR) reaching the earth?s surface. Prolonged and repeated, both occupational and recreational, sun exposure of the population causes some detrimental effects. Clothing is considered to be one of the most important tools for UV protection. It is generally accepted that synthetic fibres provide a high UV protection capability of textiles, while cellulose fibres (cotton, linen, hemp, viscose) have a low UV absorption capacity. However, natural pigments, pectin and waxes in natural cellulose fibers, and lignin in hemp fibers, act as UV absorbers having a favorable effect on UPF of grey-state fabrics. Bearing in mind the trend of reintroduction of hemp fibers as a source of eco-friendly textiles, there is a serious lack of study about the potential of hemp materials in terms of UV protection. Folded yarn is a complex yarn composed of two or more component yarns arranged parallel and twisted together to make a ?new quality? yarn. Folding of yarns is an operation undertaken in order to modify single-yarn properties to an appreciable degree. There are very few investigations concerning the relationship between the yarn properties and UV protection effectiveness of the fabric made there from. In addition, there is no any result in the scientific literature about the influence of yarn folding on UV protection properties of textile materials. Having this in mind, for our research the idea was to evaluate the effect of yarn folding in this regard. The plain knitted fabrics composed of single or two-folded hemp yarn were compared in terms of UV protection properties. The Ultraviolet Protection Factor (UPF), as the quantitative measurement of the material effectiveness to protect the human skin against UVR, was determined for the textile materials by in vitro test method according to the European standard EN 13758. The knitted fabrics construction and physical properties were also determined. Bearing in mind that plain knitted fabrics are particularly susceptible to relaxation, they were subjected to relaxation and shrinkage by wetting process, and testing procedure was repeated on the water-treated samples. The results obtained indicated that the folding operation influences UV protection properties of knitted fabrics through an influence on a loop configuration, i.e. the fabric openness. Relaxation and shrinkage of the knitted fabrics due to wet relaxation caused the reduction of macro-porosity increasing the UPF of the knitted fabrics. Although the knitted fabric produced from single hemp yarn was characterized by higher UPF, the UVR transmittance of the folded hemp yarn knitted fabric after wet relaxation placed it in the ?excellent UV protection category? (according to European Standard EN 13758-2). This fact together with the better thermal comfort manifested itself in higher air permeability, confirmed the potential of folding operation in terms of UV protection properties of textile materials.

A new development for determining the ultraviolet protection factor

Ultraviolet radiation has become an increasing problem in recent years. It causes many injuries in humans giving rise to the need for protection against ultraviolet radiation, which can be provided by textiles with a high ultraviolet protection factor. This factor can be determined by a variety of established methods. This work focuses on establishing a new methodology for determining the ultraviolet protection factor value using an ultraviolet lamp and a detector. The fabric is to be tested is placed between the ultraviolet lamp and the detector. The new method has the advantages of the existing systems but also minimizes the disadvantages. This will involve a major statistical study using linear regression. The statistical study will be completed with the analysis of residuals using the Shapiro–Wilks test, Gauss–Markov theorem, simple Analysis of variance (ANOVA) procedures, and autocorrelation and partial autocorrelation plots. The measurement error and the deviation of the samples is less than the measurement error committed by the spectrophotometric technique.

Development of a Reproducible Rating System for Sun Protective Clothing That Incorporates Body Surface Coverage

Sunlight is a known skin carcinogen. Skin cancer is the most common form of cancer in humans, and typically affects sun-exposed parts of the body. Sunny Australia and New Zealand have the highest incidence of skin cancer globally. Clothing provides a protective barrier that reduces the amount of ultraviolet radiation (UVR) reaching the skin. Australia pioneered the development of a relative ranking of the sun-protective capabilities of clothing based on the transmission of UVR through fabric. Standardized Ultraviolet Protection Factor (UPF) measurement procedures and associated labeling specifications are documented in the Australian and New Zealand Standard, AS/NZS 4399:1996. The standard was intended to enable consumers to make informed choices. Since its introduction, this standard has been adopted almost universally by the textile industry, and is still in use almost two decades on, with plans to revise it only commencing recently. However, AS/NZS 4399:1996 does not consider garment design, particularly in relation to body surface coverage. Although swim-shirts have grown in popularity in Australia since the late 1990s, particularly among children, clothing remains under-utilized as a form of sun-protection in contemporary society. Skin cancer prevention campaigns should emphasize the sun-protective benefits of clothing and collaboration with the fashion industry is urgently needed to improve the aesthetic appeal, comfort, durability and affordability of sun-protective clothing to increase its popularity in skin cancer prone populations. In light of recent evidence showing that high UPF clothing which covers more of the body surface reduces pigmented mole development in children (major risk factor for melanoma), the rating system for sun-protective clothing should incorporate body surface covered as well as the UPF of the fabric. We discuss progress towards developing a protocol for measuring the extent of coverage of sun-protective garments. Once fully evaluated and refined, the testing protocol developed from this research may influence future revisions of international standards for evaluating and classifying sun-protective clothing.

Creating cellulose fibres with excellent UV protective properties using moist CF4 plasma and ZnO nanoparticles

Weakly ionised gaseous plasma created in a moist tetrafluoromethane gas at a low pressure with an electrodeless radiofrequency discharge was applied to modify the surface properties of cellulose fibres. The plasma was used to increase the adsorption of zinc oxide (ZnO) nanoparticles such that cellulose fibres with good ultraviolet (UV) protective properties could be created. The UV protection factor (UPF) values of the ZnO-functionalised fibres were determined as a function of the plasma treatment time. The chemical and physical surface properties of the plasma-treated fibres were examined using scanning electron microscopy, X-ray photoelectron spectroscopy, and wettability tests. The quantity of zinc on the fibres was determined using inductively coupled plasma mass spectroscopy. The results indicated that 30 s of plasma treatment resulted in ZnO-functionalised samples with lower UPF values than samples without plasma treatment due to the creation of fluorine-rich functional groups on cellulose fibres and the agglomeration of ZnO nanoparticles. The highest UPF values (50+) were obtained when samples were treated with plasma for 10 s. These high UPF values were a result of the increased adsorption of uniformly distributed ZnO nanoparticles caused by fibres surface functionalization and roughening upon plasma treatment. Furthermore, the mechanical properties of textiles treated with moist CF4 plasma for 10 s were slightly improved.

UV protective textiles by the deposition of functional ethylcellulose nanoparticles

Ethylcellulose (EC) nanoparticles have been widely investigated for their use as drug delivery systems. However, their application on the textile field has been hardly studied. In this work, the use of EC nanoparticles as nanocarriers of active or lipid soluble compounds and their subsequent deposition on cotton textile is proposed in order to obtain functional textiles. A UV protective textile has been obtained after deposition of EC nanoparticles loaded with a liposoluble UV filter on cotton fabrics. The EC/cotton affinity and the attachment mechanism of EC nanoparticles on cotton substrate was studied by means of thermal behaviour evaluation, estimation of adhesion work (WA) and wash resistance tests. It is proposed that during EC nanoparticles deposition on cotton fabric, entanglement of polymeric chains is favoured, thus improving adhesion of EC nanoparticles on cotton substrate. The functionality of cotton textile was assessed by ultraviolet protection factor (UPF) measurements, showing a high UPF value (UPF = 45). Evaluation of UPF as a function of washing cycles were carried out on treated cotton fabrics. Washed fabrics still provided good UV protection (UPF ≥ 25), evidencing the presence of nanoparticles after washing cycles and the durability of the conferred functionality.

Enhancement of UV Property on Cotton Fabric by TiO2 Nanorods

TiO2 nanoparticles were prepared at low temperature using TiCl3. Rutile phase TiO2 agglomerated nanoparticles showed a rod-like morphology. Diameter of TiO2 nanorods was controlled by varying acidic catalyst and calcination temperature. At 1073 and 1273 K, nanorod was deformed to elliptical like morphology with unagglomerated particles. TiO2 nanoparticles were padded on surface of cotton fabric using silica sol and characterized comprehensively. The effect of ultraviolet protection on TiO2 nanorods coated cotton fabric was determined. High ultraviolet protection factor indicates that the TiO2 nanoparticles coated on cotton fabrics show good ultraviolet protection efficiency.

Comparative analysis of in vitro ultraviolet radiation protection of fabrics woven from cotton and bamboo viscose yarns

Ultraviolet protection factor (UPF) of fabrics made of 100% cotton and 100% bamboo viscose yarns were studied and a comparative analysis carried out using curve fitting technique. Bamboo viscose fabrics showed higher shrinkage, cover percentage, areal density and UPF compared to its cotton counterpart woven with identical yarn counts and fabric sett. However, the predictive model of cotton fabric UPF using fabric areal density as the input was able to estimate the UPF of bamboo viscose fabrics with very good accuracy. Furthermore, the 100% cotton and 100% bamboo viscose fabrics showed the same UPF if their cover percentage and areal density is similar. It is inferred from the analysis that the apparently higher UPF of bamboo viscose fabrics can be attributed to their higher cover percentage and areal density instead of bamboo’s inherent UV protective property which has been claimed in various literatures.