Apple filed a patent in the US describing a keyboard that resists crumbs. The patent includes two different strategies for how a keyboard could keep dirt out: either by sealing gaps or by a membrane under each key, ie e would blow air out with each press of the button to push out unwanted foreign matter. This is in line with the principle of a bellows.
The numbers shown in the patent make it clear that Apple is considering many different approaches and alternatives to create a crumb resistant keyboard. The patent was filed on September 8, 2016, just one day after the company officially announced the iPhone 7 and iPhone 7 Plus.
Apple states that the moving elements of a keyboard are damaged by liquids or solid particles that are present in the user's environment. In particular, it should be noted that "residues from such liquids, such as sugar, can corrode or block electrical contacts."
Of course, the patent does not guarantee that Apple will actually work on such a keyboard. With the new MacBook Pro, which are on the market since the end of 2016, but also with the MacBook 12 inch, a mechanism is used which gives a very precise typing feeling, because the keys do not tilt anymore. Many mechanical keyboards on notebooks have a scissor-like guide underneath the keycap that collapses like a lounge chair when pushed down and is also called a scissor mechanism.
The technology works a little differently on Apple's new keyboard model. The most important element is a guide that simply looks like two butterfly wings. When pressed, it is flattened and triggers the contact. The mechanism is larger than a scissors mechanism and prevents the keys from tipping at the edges. When the button is pressed on the new model, its entire surface moves down evenly.
Apple has developed this keyboard not only for supposedly better usability, but also to save space in the case. The installation depth should be lower than with traditional keyboards and this simply means that more space in the housing remains for the battery and thus the running time can be increased.
The disadvantage of these keyboards must not be concealed. So it is hardly possible to remove dirt that has once fallen between these keys. Apple recommends a compressed air spray, but cleaning the key spaces efficiently is more than difficult.