Changes

To obtain certain desired physical properties of preparations, the dispersed precious metals in flat flake-like particles (generally called "flakes") are needed. These are produced by milling fine metal powders in the presence of milling additives or agents. The properties of these metal flakes, i.e. silver flakes (ability to disperse easily, flow characteristics, electrical conductivity) are strongly dependent on the particle shape and size as well as on the type of milling agents used. (<xr id="fig:SEM photos of silver flakes a fine grain b large flat"/><!--Fig. 8.5-->) illustrates through SEM photos a type of rather fine silver flake (medium particle size 4 – 6 µm) (a) and another one with relatively large flat but thin flake shapes (particle size 8 – 11 µm) (b). Typical commercial silver flake types are listed with their respective properties in (<xr id="tab:Typical Commercial Silver Flake Types"/><!--(Tab. 8.4)-->). Gold and platinum can also be produced as powder flakes. However, in terms of the quantities used, they are of lesser economic importance.