Kryptek is apparently just hydrographic printing.
Kryptek is a pattern- not a process. Far as I know, it's trademarked- genuine Kryptek camo vinyl is crazy expensive (like $50 for a rifle), most are "knock-offs".
There are hydrographic films with the pattern inked on it.
There are also stencils with the pattern, just like many other camo patterns.
It makes practical sense that the Sig may done with hydrographics- it's the only way I could see it being done in a production environment.
Hydrographics has it's place- but certainly not on a pistol that will be holstered and especially not an EDC. These are inks- and the durability comes from the quality of the clearcoat used over it. Not as durable as high-end coatings- but much more versatile (tons of crazy patterns available) and not a bad choice for rifle stocks that won't see much abuse.
I've full supplies to do it- but have never had the time to give it a try. You can "dip" anything from ashtrays, to the dash in your car/truck, to an entire ATV...
JMO, YMMV.