Nano Particles and Nano Coatings

recently the nano coating technology is used in mobile devices, for example, mobile phone covers, bluetooth headsets, MP4 etc.. , as the word " Nano" , i presumed that the particles is very small, in nanometer, to be employed for coating process.

1) what coating process that able to coat such " nano particles" ?

2) does this coating for decoration propose or functional ?

thank you

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