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SummaryPhotochromic compounds change colour due to exposure to light while the reversion may be due either to radiation or may be thermal. The use of photochromism on fabrics can provide new opportunities to develop smart textiles, e.g. sensors and active protective clothes. Ethyl cellulose-1, 3,3,4,5 (and 1,3,3,5,6)]oxazine] composites were prepared by an oil-in-water emulsion, solvent evaporation method in order to form easily suspendable and fatigue resistant photochromic nanoparticles in screen printing paste. Their size was well below 1 m and did not change substantially in a wide range of dye concentration. After screen printing a homogenous photochromic layer was built on a cotton substrate surface, which represented substantial blue colour development in CIELAB colour space measurements due to UV light even at a dye concentration of 0.045 % w/w. The addition of a photodegradation inhibitor, Tinuvin 144 further increased the colouration of the printed fabric.

Laundering is a complex process that takes place in a water medium and is influenced by temperature, duration, washing agents (consisting of surfactants, builders, bleaching, whitening and auxiliary agents), disinfecting agents as well as mechanical treatment [1]. It is important to maintain hygiene and the quality of textile cleaning by successfully taking advantage of the beneficial interactions occurring between well-chosen detergent ingredients, using professional and responsible methods to deliver superior performance with a minimum amount of active ingredients and choosing the most optimal laundering procedure. When these factors are taken into consideration the product cost and the quantity of materials released into the environment is reduced and, at the same time, an appropriate level of quality and hygiene is maintained [2,3]. 1 Cotton fabrics have been widely used in the textile industry, representing more than 50% of the world textile production [4]. For this reason, the secondary laundering effects are usually evaluated on cotton fabrics. Secondary laundering effects consist of changes in the oxidation state, degree of polymerization, breakdown of molecular structure, loss of tensile strength, discoloration and overall change in appearance. The causes of these effects are the use of low-quality textiles and improper use of detergents, hard water, microbial growth etc. [5][6][7]. The wear and tear of cotton fabrics due to washing were primarily tested in 1908 by Leimhöfer [8]. According to Kind [9] the loss of the tearing strength of cotton fabrics after 50 laundering processes using soap, soda and perborate, varied between 30 and 85%. In 1930, Häuptli [10] gave an account of extensive Abstract Every laundry is determined to maintain or constantly improve the quality of its services. This quality is defined by parameters that are determined by standard methods. With the help of different industrial laundries some research on the influence of laundering procedure on the quality of laundered fabrics was conducted. For this purpose standard cotton fabrics were laundered 50 times or 25 times, respectively, by certain procedures. After laundering, the quality was assessed by determining the decrease in breaking strength, chemical wear, incineration residue, Ganz degree of whiteness, lightness and the Ganz-Griesser tint deviation. It was found that higher chemical and mechanical damage was mainly due to higher concentrations of hydrogen peroxide used at higher temperatures in longer laundering procedures with lower bath ratios. The quality of the investigated laundering procedures could be improved by adapting the dose of detergents, bath ratio, temperature and duration as well as the sorting before laundering.

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Cellulose nanofibrils (CNFs) were surface functionalized with hexamethylenediamine (HMDA) and, further, integrated with native CNFs in various weight mass ratios to fabricate water-stable films by the solvent casting method, to be used for the removal of tri-chromatic and anionic black reactive dye with the highest bleeding effect in the very first minutes of textile laundering, and in a weight mass compared to a commercial color-catcher sheet (Delta Pronatura (DP)). The effects of CNF-HMDA content on film bath absorption, surface potential and contact angle properties, as well as dye removal kinetics from different laundering baths (A – without and B – with a detergent) in up to 140 min were studied at 20℃ versus 60℃ and using different dye concentrations (0.1–1 g/L). It was found that bath absorption is decreased significantly (up to 60%) by increasing the CNF-HMDA content in the films, as compared to using a DP color-catcher sheet, due to a morphologically denser structure with surface-positioned hydrophobic ethylene moieties of HMDA, as well as reducing electrostatic attraction groups of CNF and HMDA. Such a surface interacts kinetically faster with anionic and hydrophobic dye molecules already at 20℃, reaching up to 37–80% removal of all dye colorants in the first 20 min. In contrast, the dye removal efficacy of the DP color-catcher sheet is due to it interacting with a cationic polymer being released from the surface, which is better only for a bluish color, and at 60℃, while being between 30% and 48%, as its release is hindered and reduced by the deposition of surfactants from the detergent.