Silver-Gelatine Metal-Dielectric Composites Made From Developed X-Ray Films

The artificial dielectric properties of developed silver-gelatine X-ray film have been evaluated at microwave frequencies. The density of the silver particles in the thin films on the surface of the plastic substrate determines the real and imaginary parts of the complex permittivity. The resulting metamaterial was evaluated between 5 and 20 GHz using the split-post dielectric resonator technique. The real part of the relative permittivity of silver-gelatine mixtures varies in the range 4-170 depending on the concentration of silver. The dielectric loss tangent for such materials is in the range 0.06-0.25 and is largest for the highest permittivity samples .