## 3 Results of the Metallization of Textiles  
After the \(Cu\) and \(Ni\) electroless plating, the textiles show a metallic appearance, like copper and nickel. A homogeneous coating of \(Cu\) or \(Ni\) is realized on the non-conductive fibers also around the full fiber diameter. The micrograph images are shown in Figure 1.  
The scanning electron microscopy (SEM) images in Figures 2 and 3A-C show that there are some nanostructures on top of the homogeneous copper layer, while the nickel coated samples show a very smooth surface, almost without such nanostructures.  
Figure 1: Micrograph images of copper-plated textiles NL-VL-S-016 (**A**), NL-WE-S-056 (**B**) and NL-WE-S-045 (**C**) and the corresponding textiles with \(Ni\) plating in (**a–c**).  
The energy-dispersive x-ray spectroscopy (EDX) of the copper layer shows that copper is the main element in this layer (Figure 4). The C and O peaks could be due to surface contamination or the fibers. In the nickel-coated layer, except for the main element of nickel, a small part of phosphorus is detected. The C and O peaks may be also due to surface contamination or the fibers. The phosphorus comes from the plating bath containing sodium hypophosphite monohydrate (\(NaH_{2}PO_{2}\cdot H_{2}\)O).  
Figure 3: High magnification SEM images at the cross-section prepared by focused ion beam (FIB) for the determination of the coated layer thickness. Fabrics produced by 55% of viscose and 45% polyester (**A**), by 100% polyestersulfone (**B**), a taffeta lined and calendered polyamide textile (**C**) coated with copper, respectively. The corresponding fabrics coated with nickel are presented in (**a–c**), respectively. Scale bar for all samples: 2 \(\upmu\)m.  
Figure 2: SEM images of copper-plated textiles consisting of 55% of viscose and 45% polyester (**A**), 100% polyestersulfone (**B**), a taffeta lined and calendered polyamide textile (**C**) and the corresponding fabrics (A-a, B-b and C-c) with Ni plating in (**a–c**). Scale bar for all the images: 100 \(\upmu\)m.  
The average thicknesses of the metal layers deposited on the fabrics have been measured at the cross-section of the fabrics prepared by focused ion beam (FIB). The high magnification of SEM images shows a layer thickness of 175 nm (fabric produced with 55% of viscose and 45% polyester), 177 nm (100% polyestersulfone), and around 200 nm (taffeta lined and calendered polyamide textile) for the Cu-plated samples, and 375-398, 180, and 226 nm for the corresponding nickel-plated fabrics, respectively.  
For experimental studies of the emissivity of reflective textiles, the standard test methods for measuring and compensating for emissions using infrared imaging radiometers (ASTM E1933) were utilized, taking into account the recommendations \"Condition monitoring and diagnostics of machines-Thermography--Part 1: General procedures. Reflector method\" (International standard ISO 18434-1). Selected results of the textile metallization using both Cu and Ni plating are given in Table 1. As seen, the utilization of Cu plating for the textile NL-WE-S-056 allowed us to attain an emissivity of 0.13. The lining thickness is very small (0.05 mm) and, therefore, the lining is neglected in the heat and humidity transport models described below. The data presented in Table 1 show the range of variations of emissivity, which is used in numerical study in Section 6.