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Leather is a material that has been used in different applications for centuries. Today, living in the era of high-tech¬nology, we are surrounded by smart products. For this reason, traditional products must be changed or im¬proved in order to support and make us more comfortable while using them. For instance, the touch screen display in electronics products is a smart phone’s or a tablet computer’s primary input device. Still, traditional leather will not function properly in a cold climate or other specific conditions. To make it conductive in such conditions, the double in-situ polymerization of the pyrrole coating method was used. The aim of this study was to observe the electrical properties of conductive leather. At the same time, it stands up to a wide range of different air temperatures, and relative and absolute humidity. These properties are essential because de¬signers and textile engineers should be familiar with them when they decide to use materials in different smart products. Electricity conductivity tests were carried out in year-round temperatures from 7.5 °C to 28.1 °C, with a relative humidity from 18% to 77% and a vapor air concentration from 2.77 g/kg to 12.46 g/kg. The so-called “multiple-step method” was used to test leather’s electrical resistivity for the first time. The method considers a material’s compressional properties and provides an indicator inherent for a material’s electrical properties, regardless of the mass and shape of samples. The results showed a strong dependence between water vapor air concentration and electrical resistivity, described using the formula ρ = 1.3103 H−1.04 Ωm, with a correlation coefficient of 0.87. There was no relation between relative humidity and electrical resistivity, and resistivity and air temperature. Also, the results confirmed again that changes in the shape of the sample used during tests did not influence the measurement’s results, but supported the appropriateness of the measuring method.

A new multiple-step method for measuring the electrical resistance of textile assem blies is proposed that takes the compressional properties of the assembly into consid eration. A new parameter is introduced to describe the electrical resistivity of textile materials as the limit resistivity of a compressed fiber assembly. This new definition approaches the measured resistance of the textile assembly as something similar to the volume resistivity of a rigid homogeneous material. Experiments with different kinds of fiber assemblies clearly show that the electrical resistivity so defined is an inherent characteristic reflecting the electrical properties of fiber material and is independent of sample form (fabric, yarn, and fiber).

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Determining the surface resistance of electro conductive refined natural leather materials is in the focus of this paper. Natural leather samples are initially transformed to conductive by applying chemical treatment process known as polymerization. Due to the existence of various techniques for measuring electrical resistance of conductive materials, we are focused on measuring surface resistance by arranging four electrodes in the edges of square leather samples, also known as Van der Pauw method. Improving the results accuracy, we use a multi-variant electrode placement over the sample edges. The result is the average of all results gained for different placements. Moreover, we use this electrode placement technique to analyse the anisotropy of conductive samples. The results of this research provide important knowledge about leather chemical treatment and its electrical proprieties.