When we first started to see leaks of the Xperia Z2, many were surprised to see a design that in many respects looked almost identical to the Xperia Z1. We know now that there were a number of changes including stereo speakers, SoC, higher RAM but what is less talked about are the small design changes between the Xperia Z1 and Z2.
One of the big changes internally in the Xperia Z2 was the use of insert molding to create a seamless structure of polycarbonate resin and metal. These parts were separate in the Xperia Z1. By integrating these together in the Xperia Z2, it allowed Sony engineers greater space leading to a larger display (5.0 ? 5.2-inch), larger battery (3000 ? 3200mAh) as well as a lighter (170 ? 163 grams) and narrower body (74.0 ? 73.3 mm). All of this was thanks to insert molding.
This structure also enabled a more waterproof structure with less points needed to be sealed. It’s fascinating to see how what seems like a small change can make a big difference. We’re very intrigued to see how Sony has moved its flagship series onwards with the Xperia Z3, even though right now, on the face of it, the changes look small.
Why Sony used Insert Molding in the Xperia Z2
The diagram below shows that the Xperia Z1 had to make sure that there were two water sealing points. The use of injection molding in the Xperia Z2 however, meant a simpler waterproof structure.
Xperia Z1 – You will notice a slight groove between the polycarbonate and metal.
Xperia Z2 – The use of insert molding leads to no-gap between the polycarbonate resin and metal.
Compare the Xperia Z1 (bottom) to the Xperia Z2 (top)