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This study was aimed to investigate the influence of low-pressure RF plasma (gas, treatment time and power) and atmospheric pressure corona (number of passages and power) parameters on decolourisation of indigo dyed denim fabrics. CIEL*a*b* colourimetric system was used for determination of colour difference between untreated and differently plasma treated denim fabrics. The morphology of plasma treated fibres was assessed by SEM analysis. The results showed that decolourisation was highly affected by plasma parameters and desired "worn look" effects could be designed by adequate control of plasma processing.

In order to study the influence of low-temperature air plasma and enzymatic treatment on the dyeing properties of hemp, "cold dyeing" of hemp fabric with acid dye (C.I. acid blue 113) and direct dye (C.I direct red 81) was performed. In addition to the determination of dyeing kinetics, colour yield and colourfastness, assessment of weight loss, water retention and whiteness degree, as well as SEM analysis of differently treated samples was carried out. Low-temperature plasma treatment of hemp fabric caused an increase in the dyeing rate, final dye exhaustion and colour yield of dyed samples. The positive effect of plasma treatment was explained by plasma etching and oxidation effect on the hemp fibre surface. Enzymatic treatment led to a decrease in the dyeing rate in the case of C.I acid blue 113 and slight increase in the case of C.I. direct red 81, whereas the final exhaustion of both dyes decreased. This behaviour has been attributed to a more pronounced digestion of amorphous fibre areas. All samples showed similar and low colourfastness values, which were considered as satisfactory, taking into account that the cold dyeing procedure was carried out.

Praćenje promena morfoloških svojstava površine vlakana nastalih modifikovanjem netkanog sorpcionog materijala na bazi vune kao sekundarne sirovine biopolimerom hitozanom i/ili niskotemperaturnom plazmom je od velike važnosti za sagledavanje mogućeg mehanizma sorpcije pojedinih zagađivača iz vodenog mediju- ma. U ovom radu su prikazani rezultati karakterizacije površine vlakna korišćenjem SEM, AFM i WLSI tehnika. An assessment of morphological properties after the modification of recycled wool-based non-woven sorbent with biopolymer chitosan and/or low-temperature plasma is of great importance for study on possible sorption mechanism for different contaminants from water medium. The results of fibre characterization using the SEM, AFM and WLSI techniques are presented in this paper. It was established that modification of sorbent material brought about changes of surface topography. Plasma treatment (LTP) caused the formation of pits and striations on the fibre surface, while chitosan (CHT) and plasma+chitosan (LTP+CHT) treatments resulted in masking the scales with biopolymer. These results are in accordance with surface roughness parameters arising from WLSI analysis.

Low-temperature plasma treatment causes modification of specific wool properties (felting shrinkage, wettability, dyeability, printability, pilling) as a result of interaction between active plasma particles and fibre surface. The formation of new functional groups on the fibre surface, physical sputtering and reactive plasma etching occur during the plasma treatment. The changes are confined to the wool surface, leaving the fibre bulk properties unchanged. Adequate choice of plasma treatment parameters provides options to achieve specific plasma-chemical reactions and consequently, the desired effects on the wool. This paper considers the influence of low-temperature plasma on the changes of chemical composition, morphological and electrokinetical properties of wool.

Obrada niskotemperaturnom plazmom povećava brzinu iscrpljenja boje, završno iscrpljenje i intenzitet obojenja tkanine od konoplje. Poboljšanja posle obrade plazmom su izraženija kod bojenja bojom C.I. acid blue 113 nego kod C.I. direct red 81. Promena ponašanja prilikom bojenja je posledica nagrizanja i oksidacije površine vlakna konoplje plazmom. Low-temperature plasma treatment of hemp fabric causes an increase in dyeing rate, final dye exhaustion and dyeing strength of dyed samples. The positive effect of plasma treatment is more prominent in case of dyeing with C.I. acid blue 113 than with C.I. direct red 81. The observed changes in dyeing behavior could be explained by plasma etching and oxidation effect on the hemp fiber surface.

Savremena obrada tekstilnog materijala ima za cilj postizanje zahtevanog efekta uz ograničavanje modifikovanja samo na površinu vlakna. U poslednje vreme se znatna pažnja poklanja fizičkim postupcima obrade, medu kojima se niskotemperaturna plazma smatra veoma pogodnom za obradu površine vlakana. Takode, postoje i veoma efikasni hemijski postupci obrade, kao što je obrada vodonik peroksidom, biopolimerima Hi enzimima. U ovom radu su pri-kazane neke interesantne kombinacije ovih fizičkih i hemijskih metoda, kojima se modifikuje topografija površine tekstilnih vlakana i na taj način se regulišu tzv. površinska svojstva tekstilnih vlakana. Dobijena svojstva su diskutovana na bazi fizičko-hemijskih promena u površinskom sloju vlakna koje su ocenjivane preko sposobnosti kvašenja i ugla kvašenja, kao i primenom FTIR/ATR i XPS analize. SEM i AFM tehnika su korišćene za odredivanje promena u topografiji površine vlakna, kako bi se one dovele u vezu sa efikasnošću, ravnomernošću i intenzitetom obrade kod postupaka za obradu površine tekstilnih vlakana. The modern textile fibre treatments aim to obtain the required level of beneficial effect while attempting to confine the modification to the fibre surface. Recently, much attention has been focused on different physical methods of fibre surface modification, cold plasma treatment being considered as very useful. Moreover, there are efficient chemical methods available, such as peroxide, biopolymer and enzyme treatment. Some interesting combinations of these physical and chemical surface modification methods as means to modify fibre surface topography and thus controlling the surface-related properties of the fibre are presented in this paper. The properties obtained are discussed on the basis of the physico-chemical changes in the surface layer of the fibre, being assessed by wettability and contact angle measurements, as well as by FTIR-ATR and XPS analysis. The SEM and AFM technique are used to assess the changes in the fibre surface topography and to correlate these changes to the effectiveness, uniformity and severity of the textile fibre surface modification treatments.