Mercerisation changes the fine structure, morphology and conformation of cotton cellulose chains (cellulose I to cellulose II), resulting in a variation in fibre strength and lustre as well as adsorption properties. Recently it has been shown that mercerisation also changes the electrokinetic behaviour of cotton. The aim of the work presented here is to study the behaviour in unmercerised and mercerised cotton. The zeta potential of cotton fibres was measured by the streaming current method, using an EKA electrokinetic analyser. The relationships between zeta potential and the pH of a potassium chloride solution on the one hand and the point of zero charge (PZC) on the other, determined by titration with a cationic surfactant (cetylpyridinium chloride), were investigated.

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Surfactants as organic compounds are widely used in the processes of textile finishing and care with regard to different variations and specific hydrophilic/hydrophobic character. Specific behaviour of these compounds is partly based on the adsorption process. In this study the adsorption and desorption of ionic surfactants have been studied upon the influence of fibre composition and surfactant ionogenity as well as variation of hydrophobic chain length and hydrophilic group in the molecule. Textile fibres were characterized through electrokinetic potential, sorption characteristics and swelling capacity expressed by moisture regain and water retention value (WRV). Different types of cationic and anionic surfactants were adsorbed on cotton, wool, polyester and polypropylene fibres at 20°C during 60 minutes. The quantity of adsorbed surfactants on textile fibres was determined by potentiometric titration. The textile fibres were centrifuged afterwards and the amount of surfactants was determined in the centrifugate, respectively. Drying followed at 60°C. The desorption of surfactants was performed at 20°C during 30 minutes. The results showed a correlation between amount of adsorbed, desorbed and residual surfactants and swelling capacity expressed through WRV.

The influence of wet cleaning, as a promising process compared to washing, on the physical and chemical properties of functional cotton fabrics with high added value is presented. Fabric characterization before and after durable press finishing and after 10 cycles of washing and wet cleaning is made using standard methods – measuring dimensional stability, construction characteristics, crease resistance, tensile properties, swelling properties, appearance with coefficient of friction and geometrical roughness, surface characterization by scanning electron microscopy and electrokinetic potential. It can be seen that wet cleaning, which has been used in practice, together with adequate pretreatment, as a substitute for dry cleaning, can also be successfully implemented as a process to substitute washing, particularly when high-value-added articles are concerned.

Bleached cotton and polyester/cotton blend fabrics were laundered at 60°C and 90°C with standard ECE detergent with addition of selected fluorescent compounds through 10 cycles. As fluorescent whitening agents for cellulosic materials are most often used in detergents, two types of these were selected – stilbene and biphenyl. UV absorber, a stilbene derivative, as a separate type of fluorescent compounds, was added on its own and in a combination with both types of fluorescent whitening agents. After each laundering cycle cotton and PES/cotton blend fabrics were exposed to artificial light for 60 and 180 minutes. Obtained optical and protective effects were monitored through whiteness degree, remission and Ultraviolet Protection Factor (UPF). Optical effects of cotton fabrics laundered in a detergent containing fluorescent whitening agents of stilbene and biphenyl type exhibit considerable sensitivity to light. It was not found that irradiation reduces the UPF meaning that even decomposition products of fluorescent compounds, created by irradiation, absorb UV radiation as well.

Textile metal threads were used to decorate historical Croatian textiles. There are three basic types of metal threads usually used on historical textiles in Croatia. These are narrow stripes, wires, and combined metal textile yarn called “srma”, made of metal thread spirally wrapped around the nonmetal textile yarn. Textile yarns were made of silk, linen, wool, or cotton. Metal threads were primarily made of gold, silver, and copper, and different alloys of these metals or threads are layered in the structure. Analysis of metal threads with three different methods was made and the most adequate method for the analysis of metal threads from historical textiles was established. Metal thread analysis was performed with scanning electron microscopy with an energy-dispersive X-ray detector (SEM-EDX), which was determined to be the most suitable for the analysis of historical textiles if cross-section analysis of metal threads is also performed. Textile threads from combined metal textile threads were analysed with a light microscope. This information of the metal threads’ content and structure as well as the composition of textile thread can lead to an understanding of the technology of production threads and also temporal and spatial dating of textile objects which is helpful to conservators and restorers of valuable historical textiles.

Cellulases are enzymes that are used for the surface modifi cations of cellulosic materials primarily during fi nishing. It is a multi-component enzymatic system which hydrolyzes cellulose chains, on the surface of the fi bres, to glucose. During their applications in the fi nishing of textiles, surface fi bres are removed and the surfaces of the treated textiles become smooth. The most important application is in the processing of denim for providing special eff ects without signifi cant fabric loss of strength. Enzymes are eff ective over mild conditions of pH and temperatures and are easily biodegradable.Izvleček Celulaze so encimi, namenjeni površinski modifi kaciji celuloznih tekstilij, predvsem pri plemenitenju tekstilij. Večkomponentni sistem encimov hidrolizira celulozne makromolekule na površju vlaken do glukoze. Z uporabo celulaz pri plemenitenju tekstilij se odstranijo štrleča vlakna na površju tekstilije, s čimer postane obdelano površje gladko. Med najpomembnejše vrste uporabe celulaz spada plemenitenje denim jeansa, kjer dosežejo posebne učinke brez bistvenega znižanja trdnosti tkanine. Encimi so učinkoviti v blagih pogojih vrednosti pH in temperature in so enostavno biorazgradljivi.

The influence of iron ions at concentrations of 0.2, 0.5, and 1.0 g/L on optical brighteners of the groups stilbene and biphenyl in solution and on cotton fabric was investigated. Both groups of optical brighteners are intended for detergent formulations. The influence of iron ions was studied by absorption and fluorescence spectra in solution and by whiteness degree, identifying color differences using CIEL*a*b* coordinates and Ultraviolet Protection Factor (UPF) of cotton fabrics. The obtained results in solutions and cotton fabrics showed different behavior of optical brighteners stilbene and biphenyl in the presence of iron. Stilbene compounds with metal ions produced new species capable of absorbing in the UV-B region of the spectrum. A biphenyl compound in combination with iron had no effect on the absorption properties. Both optical brighteners were influenced by iron ions in the sense of fluorescence quenching. The influence of iron ions in single- and two-bath treatments of cotton fabrics after one cycle on whiteness degree and UPF was negligible.