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The article is an invitation to the Autex 2022 - 21st World Textile Conference, which is organized by the Faculty of Material Technologies and Textile Design, Lodz University of Technology, Lodz, Poland. The conference will be held ONLINE on the 7th to the 10th June 2022, under the motto Passion for innovation. The conference will be focused on the latest scientific and technical achievements in the field of textiles.

In this work, a method for the measurement of one-dimensional (1D) UV radiation dose is described. It comprises a new tablet dosimeter that measures the dose using reflectance spectrophotometry. The tablet dosimeter elaborated is a solid structure with a cylindrical form and has been manufactured with polycaprolactone (PCL) doped with a representative of tetrazolium salts: 2,3,5−triphenyltetrazolium chloride (TTC). The PCL used makes the dosimeter biodegradable and therefore proecological. The TTC dopant is distributed uniformly in the whole PCL tablet, and the whole tablet changes color to red under UVC irradiation. The intensity of this color increases if the PCL–TTC tablet absorbs higher doses. The color of the tablet is stable for at least 30 days after irradiation. It is proposed that the PCL-TTC tablet be used for measurement with reflectance spectrophotometry in order to determine the reflectance of light versus the absorbed dose in a fast and easy manner. On this basis, the PCL-TTC tablet could be characterized by providing information on its dose range, which amounted to 0–2 J/cm2. Moreover, other parameters were derived, such as dose sensitivity, quasilinear dose range, and dose threshold. The morphology of the tablets studied using scanning electron microscopy revealed their high porosity, which however did not influence the reflectance measurements with the aid of the chosen instrument. UVC irradiation at a dose (15 J/cm2) much above the PCL-TTC tablets’ dose range did not alter the morphology of the tablets. The PCL-TTC tablet read with reflectance spectrophotometry is shown to be a promising and fast method for 1D UV dose measurements.

This work reports a modification of a fibrous cellulose material (paper) by the addition of polyacrylonitrile (PAN) fibres doped with 10,12–pentacosadiynoic acid (PDA). The fibres are sensitive to ultraviolet (UV) light. When the paper containing PAN–PDA is irradiated with UV light it changes colour to blue as a consequence of interaction of the light with PDA. The colour intensity is related to the absorbed dose, content of PAN–PDA fibres in the paper and the wavelength of UV radiation. The features of the paper are summarised after reflectance spectrophotometry and scanning microscopy analyses. All the properties of the modified paper were tested in accordance with adequate ISO standards. Moreover, a unique method for assessing the unevenness of the paper surface and the quality of printing was proposed by using a Python script (RGBreader) for the analysis of RGB colour channels. The modification applied to the paper can serve as a paper security system. The modified paper can act also as a UV radiation indicator.

This work reports on the surface-modified woven fabrics for use as UV radiation sensors. The cotton and polyamide fabrics were printed with radiochromic hydrogels using a screen-printing method. The hydrogels used as a printing paste were composed of water, poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (Pluronic F-127) as a gel matrix and nitro blue tetrazolium chloride as a radiation-sensitive compound. The development of the hydrogels’ colour occurs after exposure to UV radiation and its intensity increases with increasing absorbed dose. The features of the NBT-Pluronic F-127 radiochromic hydrogels and the fabrics printed with the hydrogels were examined using UV-Vis and reflectance spectrophotometry as well as scanning electron microscopy (SEM). The effects of NBT concentration and UV radiation type (UVA, UVB, UVC) on dose responses of the hydrogels and printed fabrics were also examined. The results obtained reveal that the fabrics printed with NBT-Pluronic F-127 hydrogels can be potentially useful as UV radiation sensors.

In this work, we propose a novel method for the preparation of polypyrrole (PPy) layers on textile fabrics using a reactive inkjet printing technique with direct freezing of inks under varying temperature up to −16 °C. It was found that the surface resistance of PPy layers on polypropylene (PP) fabric, used as a standard support, linearly decreased from 6335 Ω/sq. to 792 Ω/sq. with the decrease of polymerization temperature from 23 °C to 0 °C. The lowest surface resistance (584 Ω/sq.) of PPy layer was obtained at −12 °C. The spectroscopic studies showed that the degree of the PPy oxidation as well as its conformation is practically independent of the polymerization temperature. Thus, observed tendences in electrical conductivity were assigned to change in PPy layer morphology, as it is significantly influenced by the reaction temperature: the lower the polymerization temperature the smoother the surface of PPy layer. The as-coated PPy layers on PP textile substrates were further assembled as the electrodes in symmetric all-solid-state supercapacitor devices to access their electrochemical performance. The electrochemical results demonstrate that the symmetric supercapacitor device made with the PPy prepared at −12 °C, showed the highest specific capacitance of 72.3 F/g at a current density of 0.6 A/g, and delivers an energy density of 6.12 Wh/kg with a corresponding power density of 139 W/kg.

In this work we discuss UV and ionising radiation induced processes in the flat foils (films). The foils were made from poly(vinyl alcohol) (PVA) and either 10,12-pentacosadiynoic acid (PDA) or a representative of tetrazolium salts − 2,3,5-triphenyl tetrazolium chloride (TTC). Also, we proposed a very attractive modification of the surfaces of the foils by vapour deposition of parylene C. This lead to an alteration of the UV dose response of the foils and improved their water-resistance thus making them potentially useful for radiation dose measurements when immersed in water. The TTC- and PDA-containing foils were shown to respond to ionising radiation in a high dose range of up to 3 kGy. The PDA foils were of a higher dose sensitivity and much lower dose threshold than those containing TTC. Whereas the TTC-containing foils were of irreversible character, those containing PDA showed high reversibility both to UV and ionising radiation. Basic features of such reversible-foil dosimeters are presented. Additionally, the mechanism of radiation induced changes in the TTC- and PDA-PVA films is analysed by using UV–vis spectrophotometry and Raman spectroscopy techniques.

The subject of this work are microfibres that are made of polyacrylonitrile (PAN) doped with nano-particles of 10,12-pentacosadiynoic acid (PDA) with a mean hydrodynamic diameter of ca. 22 nm, as measured by dynamic light scattering (DLS). Two kinds of microfibres were obtained from a DMF solution (multifilaments – a bunch of 250 microfibres): glossy (diameter: ~ 11–15 µm) and lustreless (diameter: ~ 27–31 µm). The fibres responded to ionising radiation by colour changing from white to dark blue or dark blue-brown thanks to the PDA nanoparticles; the colour intensity was related to the absorbed dose of radiation. The chemical changes inside the fibres were followed with the aid of Raman spectroscopy. Reflectance spectrophotometry was chosen for characterisation of the fibres by reflectance [%] versus absorbed dose [Gy] relations, which revealed that the lustreless fibres were more susceptible to irradiation. The fibres responded to high-dose ranges and were saturated at about 8 and 15 kGy, for lustreless and glossy fibres, respectively. The fibres were very stable; they did not change their colour after irradiation within at least 30 days. The dose response of the fibres was independent of the dose rate and the way the dose was delivered: in fractions or non-fractioned. The PAN-PDA fibres were used for flat woven textile preparation to serve as 2D radiation dosimeter. An approach to 2D dose distribution analysis using the PAN-PDA textile samples is presented.

In this work a method of preparing UV-sensitive fibres is presented. The fibres are made of polyacrylonitrile by wet spinning and 2,3,5-triphenyltetrazolium chloride (TTC), 4,4′,4″-tri-di-β-hydroxyethyloaminotriphenyloacetonitrile (HHEVC) and 10,12-pentacosadiyonic acid (PENTA) are used as dopants. Preparing the fibres is a two-step process, allowing for the preparation of two kinds of fibres with different characteristics: glossy and lustreless. When the fibres are UV irradiated they change colour, to yellow for TTC and blue for HHEVC. Those with the PENTA dopant undergo a complex colour change since at lower doses blue colour formation is initiated but at higher absorbed doses a red colour appears that finally leads to a brown colour in the fibres. The colour formation and its intensity are related to the absorbed dose and the wavelength of UV radiation. The fibres possess different morphologies and mechanical properties that depend on the preparation method. XRD analysis revealed a distinct difference between the glossy and lustreless fibres in that the former are of higher crystallinity that translates into better mechanical properties of the fibres. The impact of the dopants on the crystallinity and mechanical properties of the fibres is also discussed. One possible application of the fibres is for UV absorbed dose detection. Nevertheless, they were designed to serve as elementary units to be further manufactured into a flat textile as a 2D radiation dosimeter.

In this work, a reactive inkjet printing (RIP) has been proposed as an useful method for the deposition of reduced graphene oxide (RGO) layers on different textile fabrics - polyacrylonitrile, poly(ethylene terephthalate), and polypropylene. Under the RIP process, the RGO layers were grown on fabrics by printing of graphene oxide (GO) suspension and simultaneously reduced by L-ascorbic acid. This strategy is a simple and one step process to grow conductive layers of RGO on textile substrates at large scale without any post treatment and does not require any corrosive reagent during the process. Thus, obtained binder-free RGO on textile fabrics can be readily used directly as an electrode material. The applicability of the selected textile fabrics modified by RIP deposition of RGO for energy storage application was tested. For this, a flexible all-solid-state supercapacitor was constructed using two RGO coated textile fabrics as electrodes separated by gel electrolyte (poly(vinyl alcohol)/H3PO4 electrolyte). The as-obtained supercapacitor exhibited an area specific capacitance of 13.3 m F/cm2 (79.9 F/g) at a current density of 0.1 mA/cm2, and delivered an energy density of 1.18 mW h/cm2 and the power density of 4.6 mW/cm2.

Flat woven polyamide textiles were chosen for modification with nitro blue tetrazolium chloride (NBT) or 2,3,5-triphenyltetrazolium chloride (TTC). Such samples change colour from white to blue (NBT) or red (TTC) if exposed to ionizing radiation or UV light. When inhomogenously irradiated, a clear pattern of the absorbed dose distribution is visible to the naked eye. Performance of quantitative 2D analysis with the aid of a flat-bed document scanner was proposed. Most importantly, the application of a scanner is an easy method for the assessment of irradiated samples. Therefore, scanning parameters such as resolution, sharpness, scanning reproducibility and sample preparation were assessed in this work; and optimal parameters were chosen. The cause of uncertainty in the measurements is discussed.

The development of flat woven fabric-based ionizing radiation 2D dosimeters is reported in this work. Polyamide fabric was surface modified with radiation-sensitive 2,3,5-triphenyltetrazolium chloride (TTC) or nitro blue tetrazolium chloride (NBT). These samples responded to gamma radiation of 60 Co through a colour change: red and blue for TTC and NBT, respectively. The tinge intensity was observed to depend on the absorbed dose, which allowed for the reflectance of light ( R ) measurements and calculation of the calibration parameters: dose range, quasi-linear range, threshold dose and sensitivity. Oxygen was shown to be an important factor determining the dose response of the samples. For this reason, a range of additional modifications to the TTC- and NBT-polyamide fabric was proposed which lead to a decrease in the threshold dose and increase in the sensitivity to irradiation of the samples. For instance, a dosimeter made of polyamide fabric modified with 10 g/dm 3 TTC, 0.5 mol/dm 3 tert-butyl alcohol, 7.5% gelatine hydrogel at pH 10 (vacuum packed) showed the lowest dose threshold (50 Gy), dose range up to 2.8 kGy and the highest sensitivity to irradiation (−0.0396%/Gy) among the compositions studied. In consequence, this dosimeter was examined in terms of response to inhomogeneous irradiation from a 192 Ir brachytherapy radiation source. The relative dose distribution profiles across the source's longitudinal axis were calculated. This showed potential of the textile dosimeters for 2D dose distribution measurements; however, further modifications towards improvement of the dosimeter's low dose response can be considered.

A range of fabrics was selected for examination as material for construction of 2D radiation dosimeters as a consequence of previously obtained results confirming the possibility of radiation dose measurement with the modified polyamide textiles. These fabrics were surface finished with either 2,3,5-triphenyltetrazolium chloride (TTC) or nitrotetrazolium blue chloride (NBT). Under UV light irradiation the fabrics change colour to reddish (TTC) or bluish (NBT). The tinge intensity depends on the absorbed dose, which was analysed through the reflectance of light measurements. Some parameters of the samples are discussed in this work, such as dose sensitivity, quasi-linear and dynamic dose response, which allowed the samples that were potentially attractive for 2D dosimetry to be selected. The textile samples were assessed in terms of 2D measurements with the application of a computer operated scanner. The accuracy of 2D measurements was found to depend on the type and structure of fabric and tinge distribution after irradiation as well as additional polymer finishing of the textiles.

An approach to printing of flat textiles is presented in this work. A screen-printing method was applied on a cotton fabric. An aqueous printing paste was prepared from thickening and crosslinking agents and an ultraviolet-sensitive tetrazole ring-based compound of 2,3,5-triphenyltetrazolium chloride or nitrotetrazolium blue chloride. After the printing process, a pattern was just visible with the naked eye. The development of colour occurred after exposure of the textile to ultraviolet light of 253.7 nm and was caused by the transformation of 2,3,5-triphenyltetrazolium chloride or nitrotetrazolium blue chloride salts into the corresponding formazans, which are insoluble in water. The printed designs were resistant to washing. The stability of the colour of the samples is discussed in the case of prolonged irradiation, both with ultraviolet light of 253.7 nm and with daylight. This method of printing is a recent proposition for creative textile designing. It also seems to indicate a likely type of dye that may be further developed as potentially attractive for ultraviolet-assisted printing or dyeing of textiles.

This paper reports on the preparation and features of a UV light dosimeter composed of nitro blue tetrazolium chloride (NBT) and polyamide woven fabric. This textile dosimeter is based on the conversion reaction of NBT into formazan, which was initially examined in aerated aqueous solutions through steady state UV irradiation. Irradiated solutions change their colour as a consequence of the formation of polydisperse NBT formazan particles. This was analysed in relation to the absorbed dose of UV light through UV–VIS spectrophotometry and dynamic laser light scattering measurements. When NBT substrate molecules are embedded in polyamide textile, UV irradiation leads to similar effects as in solution. However, the tinge intensity changes at much lower absorbed doses. The dependence of the tinge intensity on the absorbed dose was followed by measurements of the remission of light from the NBT-polyamide samples. Consequently, the calibration parameters were calculated such as the dose sensitivity, dose range, and quasi-linear dose range. An improvement of the NBT-polyamide samples by application of a colour levelling agent and improvement of their resistance to humidity is presented. Finally, the samples were used for estimation of absorbed UV energy distribution showing their capability as new dosimeters for in-plane high resolution radiation dose measurements.

In this paper, results on the construction of a new flat textile-based UV light dosimeter are reported. As a textile support polyamide woven fabric was chosen, which was surface-modified with 2,3,5-triphenyltetrazolium chloride (TTC). At first, spectrophotometric and dynamic laser light scattering results on the steady-state UV irradiation of aqueous TTC solutions in the presence of oxygen are discussed. If irradiated, TTC converts to the corresponding formazan molecules of red colour. The size and size distribution of the particles is related to the absorbed radiation and pH of the solution. When TTC molecules reside on polyamide textile, UV irradiation causes a colour change from white to deep red. The tinge intensity depends on the absorbed energy per unit surface area. On this basis, the calibration parameters of the detectors, such as dose sensitivity, dose range, quasi-linear dose range, were calculated. Furthermore, the improvement of the dosimeters’ resistance to atmospheric conditions was achieved and assessed through washing fastness tests. Finally, the detectors were proved to be adequate for measurements of the 2D distribution of absorbed UV energy. A simple method of UV dose distribution measurements was proposed. The textile-based systems show promise as dosimeters.

In this study, we present facile antimicrobial finishing of cotton textiles. Screen printing was used for surface-finishing of cotton using a printing paste containing silver nitrate. UVC irradiation was applied to convert silver nitrate into a color product, thus also changing the color of the textiles. The color, its strength and stability of samples, depend on absorbed UVC energy and the formula of the printing paste. Scanning electron microscopy with the energy dispersive X-ray spectrometry revealed formation of silver particles on cotton threads; X-ray diffraction analysis and the time-of-flight secondary ion mass spectrometry did not provide clear information on these products. Microbiological studies revealed that the samples inhibited proliferation of Escherichia coli, Bacillus subtilis and Staphylococcus aureus. Washing fastness tests confirmed resistance of the samples to at least 50 washings. Additionally, the inhibition zones increased as the number of washing cycles increased, which is unique for such samples. This work also presents an approach to the design of antimicrobially finished workwear.