No abstract

The aim of the paper was to test the changes of thermo-physiological properties of fabrics occuring during the clothing maintenance, i.e. washing. Hot plate measurements were used. The test results were not observed separately but in terms of interrelatedness of the material properties. The obtained results show that certain yarn properties have a substantial impact on the change of water vapour resistance of the fabrics (Ret), and were used to establish a mathematical model for predicting thermophysiological comfort of woven structures while being used, i.e. cared for. The conducted research enabled the description, classification and definition of the elements of relatedness of fabric parameters with thermophysiological properties of a cloting item, based on which the comfort parameters of similar fabrics, as well as the usage properties of the products made of them can be predicted.

The infl uence of using formic, oxalic, citric, tartaric, hydrochloric, nitric, sulphuric and phosphoric acid for dyebath pH adjustment was investigated upon the dyeing of polyester fabric with CI Disperse Yellow 60. The positions of colour in CIELab coordinates of the samples dyed with the addition of tested acids were assessed and compared to those dyed with the addition of acetic acid. It was found that the differences in dyeabilities obtained with the addition of citric, oxalic, hydrochloric, nitric and sulphuric acid are entirely acceptable according to both M&S 83A and CMC (2:1) standards in comparison to the dyeability obtained with the addition of acetic acid.

In the false twist texturing process, due to the action of mechanical forces and heat, a disorientation of structural elements happens at all levels of the supramolecular structure. These changes are related to changes in the texturing parameters and mechanical properties of yarn. In this paper, investigated is the effect of technical-technological texturing parameters in the false twist texturing process on the structure of PA6.6 yarns. POY multifilament PA6.6 with a fineness of 22f07x1 dtex was used as experimental material. The yarn was textured on a friction texturing machine - ICBT model FT 15 E3. The exiting yarn speed (Vi) changed as 600, 700, 800 and 900 m/min; the heater temperature (T) was 200, 210 and 220 °C, and the ratio of the disk surface speed to the linear yarn speed (D/Y) was 1.9 and 2.1. The values of strain were kept constant at 1.305 (tension in texturing zone) and 0,954 in the winding zone. Analysed were the density, degree of crystallinity, degree of orientation, single filament diameter, the content of -NH2 and -COOH end groups, and the total content of end groups. From the results obtained it can be seen that the effect of the heater temperature is more significant than that of Vi and D/Y on the structural characteristics analysed. Analysing the experimental results it was found that linear positive correlations were established between the texturing speed and end (-NH2) groups, the texturing speed and end (-COOH) groups and the texturing speed and the total content of end groups. The correlation factor between the process parameters and yarn structural characteristics analysed is determined.

The variation of texturing process parameters within the limits of the industrial texturing machine brings about substantial structural changes of yarn characteristics. To obtain required characteristics of textured PA6.6 yarns for specific purposes, it is necessary to adjust the optimum process parameters. For that reason, in addition to modification of the quality of textured polyamide yarns, the aim of this work is to define the limit values of the texturing process. In this work, the influence of technical-technological parameters in the false twist texturing process on structural characteristics of polyamide yarns was studied. Partially oriented POY multifilament of 22f07×1 dtex fineness was textured under production conditions on the friction texturing machine ICBT, model FT 15 E3. Using low temperature long heaters, the influence of variations of the heater temperature, texturing speed and D/Y ratio on the properties of the textured yarn (filament density, the crystallinity degree, the orientation degree of individual filaments, end -NH 2 group content, -COOH group content and the total content of end groups) was investigated. Thereby, the values for the tension in the texturing zone (stretching) of 1.305 and in the winding zone of 0.954 were kept constant. The studied texturing parameters affect the change of above mentioned characteristics to a varying degree. For heater temperatures of 200, 210 and 220 °C, and D/Y ratio of 1.7, 1.9, 2.1 and 2.3, negative linear correlations were found between the speed of texturing -filament density, the speed of texturing -the degree of crystallinity and the speed of texturing -the degree of orientation of individual filaments. The correlation factor between the texturing process parameters and the analyzed properties of the yarn was determined. Based on the analysis of the obtained results, it can be concluded that with the established correlation between the speed of texturing and the investigated properties of the yarn, the correlation factor generally increases with the increase of D/Y ratio to 1.9 and 2.1, for the heater temperature up to 210 °C. However, in most cases the correlation factor decreases at the temperatures above 220 °C and higher values of the D/Y ratio. Therefore, in this study, the optimum temperature of the heater is 210 °C and D/Y ratio from 1.9 to 2.1, taking into account the selection of other values of texturing speed parameters and stretching.