## 4 Conclusions  
(1) In this study a novel multi-functional, antimicrobial polyester-copper \"hybrid\" composite material, PETE-Cu\({}^{(0)}\), has been produced by one-step magnetron copper sputtering on PETE knitwear fibers (composed of poly(ethylene terephthalate) knitted textiles, PET (95%) and elastane, EA (5%)).  
(2) The structural characterizations of the new PETE-Cu\({}^{(0)}\) polymer composites obtained, were characterized by Scanning Electron Microscopy (SEM) and UV/VIS transmittance. The chemical compositions of the PETE-Cu\({}^{(0)}\) composites obtained were achieved using Energy-Dispersive X-ray Spectroscopy, EDS (C, O, Cu surface analysis) and Atomic Absorption Spectrometry with Flame Excitation, FAAS (Cu content in the bulk).  
(3) The application utility of the PETE-Cu\({}^{(0)}\) composites was established by determination of their technical parameters, including filtration parameters, tensile strength, thickness, thermal and steam resistance, steam permeability, the barrier properties against UV radiation and also antimicrobial tests against _Escherichia coli_, _Staphylococcus aureus_ and _Chaetomium globosum_ fungus species.  
(4) SEM images of PETE-Cu\({}^{(0)}\) composites revealed that the applied magnetron sputtering of the starting PETE textile did not exhibit substantial destruction of the textile structure. Moreover, the described PETE-Cu\({}^{(0)}\) composites have shown improvement of the technical parameters, including air permeability and thermal and steam resistance. PETE-Cu\({}^{(0)}\) composites exhibited improvement of barrier properties against UV radiation in comparison with the unmodified PETE sample.  
Figure 9: The PETE-Cu\({}^{(0)}\) composites antimicrobial activity tests against _Chaetomium globosum_. Inhibition properties of fungal growth on Petri dishes: (**a**) PETE, (**b**) PETE-Cu\({}^{(0)}\)-1; (**c**) PETE-Cu\({}^{(0)}\)-2.  
\begin{table}
\begin{tabular}{c c} \hline \hline
**Sample Name** & **Fungal Average Inhibition Zone (mm)** \\ \hline PETE & 0 & Visible growth on sample surface \\ \hline PETE-Cu\({}^{(0)}\)-1 & 3 & No visible growth on sample surface \\ PETE-Cu\({}^{(0)}\)-2 & 3 & \\ \hline \end{tabular} Inoculum concentration, number of fungal spores in 1 ml; [CFU/mL] = \(22\times 10^{6}\) (determined using a Thoma chamber).  
\end{table}
Table 9: Results of tests on the antifungal activity of PETE-Cu\({}^{(0)}\) composites, procedure in accordance with the PN EN 14119: 2005 point 10.5 (B2) [120].  
(5) Determined antimicrobial properties of PETE-Cu(\({}^{0}\)) composites revealed the significant antibacterial action of both PETE-Cu(\({}^{0}\))-1 as well as PETE-Cu(\({}^{0}\))-1 composites against _Escherichia coli_, _Staphylococcus aureus_ and _Chaetonium globosum_ fungus species.  
(6). Recapitulating, the PETE-Cu(\({}^{0}\)) composites obtained, due to exhibited beneficial antibacterial and also technical properties, can find an application in a medical sector, for example, as a microbial barrier material.  
[PERSON] developed the concept and designed experiments, performed experiments, analyzed data and wrote the paper; [PERSON] performed experiments, analyzed the data and participated in the publication preparation; [PERSON] performed experiments, analyzed the data and participated in the publication preparation; [PERSON] participated in the publication preparation. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the Polish Ministry of Science and Higher Education within statutory research work carried out at The Lukasiewicz Research Network -Textile Research Institute, Lodz, Poland.  
This work was partly supported by National Science Centre, Poland via Grant: Miniatura 2, No. 2018/02/X/ST8/01775. The authors would like to thank [PERSON], for performing SEM and EDS analyses and [PERSON], for providing the FAAS facilities.  
The authors declare no conflict of interest.