zsas, it's beyond just a descriptor to highlight a factually different aspect, they use it to strongly imply its superior. Like saying, this car is red. Red cars run better and last longer.

"SILVERMAX has an increased silver-content compared to regular films.
This enables him to built up more DMAX and reproduce up to 14 zones in our dedicated SILVERMAX Developer.
This way SILVERMAX catches it all for you: brightest highlights and deepest shaddows."