Low Cost Embedded Copper Mesh Based on Cracked Template for Highly Durability Transparent EMI Shielding Films  
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radio navigation, mobile and satellite communications, TV and radio broadcasting, Wi-Fi, etc. For the correct operation of high-precision electronic devices, human life support systems, as well as information protection, it is crucial to effectively protect such devices from parasitic radio emission, which is implemented mainly through the use of materials, design and technological solutions based on them providing radio shielding in various frequency ranges. At the same time, at the moment, there is an increasing demand for materials that, in addition to shielding, have a different combination of such performance properties as flexibility, transparency in various spectral ranges, low weight and thickness, air permeability, etc.  
To date, significant progress has been made in developing shielding materials. In particular, such lightweight, durable and affordable materials as carbon nanotubes, graphene, MXene paper [1; 2; 3; 4], aerogels [5; 6; 7; 8] and polymer composites [9; 10] and copper nanosheets films [11] with a shielding coefficient \(SE\) not less than 60-100 dB have been developed. At the same time, these materials are opaque in the visible range. They are not suitable for solving problems of shielding transparent objects: displays of smartphones, computers and measuring instruments, glazing elements of special-purpose buildings, etc.  
The best balance between optical transparency and shielding is metallic micro and nanostructures. In the context of transparent, high-performance coatings with \(SE\) more than 30 dB, it is advisable to consider layers based on highly conductive metals, for example, Ag nanowires [12; 13; 14; 15] and Cu nanowires [16]. Additional electroless deposition of Cu on Ag nanowire seed contributes to a dramatic increase in \(SE\) for a wide frequency range [17]. Lithographic micro and nanomeshes, also widely presented in the literature, demonstrate high optoelectronic parameters and \(SE\): Ag ring micromesh [18], Cu square nanomesh [19], Cu-Ni square micromesh [20] and Ag-Ni stochastic micromesh [21]. Recently, much attention has been paid to obtaining micro and nanomesh coatings based on self-organization processes. Such methods can significantly reduce the cost of coating production and achieve high optoelectronic parameters and \(SE\). The following solutions can be cited as example: cracked template Ag mesh [22] and Cu-Ag; Ni-Ag meshes [23]; and Ag nanoparticle mesh emulsion template [24]. An important feature of the cracked template is the non-periodic mesh structure; therefore, in a multilayer version, the system will not have a moire pattern [21; 23], which is typical for the imposition of periodic meshes [19].  
This paper proposes a simple strategy for producing embedded Cu meshes obtained by electroplating copper on a Cu seed mesh formed based on a cracked template, followed by embedding in a photocurable resin (Figure 1).  
Figure 1: Technological process for obtaining an embedded Cu mesh transparent conductive coating.  
From an economic point of view, Cu seed mesh is more profitable than Ag seed mesh, which we used in [23]. The technological process of embedding a mesh into a photocurable resin layer contributes to a significant increase in the mechanical adhesion properties of the coating.  
We believe that in solving the problem of shielding transparent objects, these materials will become an excellent alternative to micro and nanomeshes obtained by lithography methods, since these methods significantly limit the possibility of scaling the technology over large areas and increase the cost of such materials.