Patent page:
LINK
PS: I am really not an Apple fan ...
Update (21.2.2016.)
Autodesk has patented color 3d printing also. Maybe it is the beginning of color patent wars.
http://3dprint.com/74984/autodesk-patent-multi-color/
Update (19.3.2016.):
Apple has filed for a new patent connected to 3d printing and molding technologies:
Apple’s patent application covers a method for 3D printing investment molds to be filled with molten amorphous alloy. These alloys are configured to form a bulk metallic glass (BMG) on cooling. BMGs, (also known as Bulk Amporhous Alloys) are a new class of metallic alloys that are extremely strong, with superior elastic strain limits and resistance under shock impact. They are therefore ideal for the manufacturing of electronic device housings and cases.Here is a patent page: LINK
Looks like Apple is going into transformable and liquid metals!!! Remember Terminator ...
Source and ore info:
http://www.3ders.org/articles/20160310-apple-files-patent-application-for-3d-printing-investment-molds.html