Apple files for “Oleophobic coating on sapphire” patent application and this further proofs that the Cupertino, Calif. company is planning to use a sapphire glass display on future iPhone’s.
Oleophobic or oil-repelling coatings were first used on the iPhone 3GS and Apple has been using it on iPhone’s and iPad’s since. The document notes that sapphire glass doesn’t react the same way to this coating the way Gorilla Glass does due to its crystal structure. So it is believed that Apple will be using a sapphire-transitional layer(gorilla glass)-surface layer sandwich to help keep the sapphire’s hardness while also having a functional oleophobic coating.
There have been several clues in the past that have pointed to Apple working on a sapphire glass display for the iPhone 6 and in November the company partnered with sapphire producer GTA Technologies which have lead many to believe that this will lead to sapphire displays in the near future.