The Cannon printer in the earlier post does not use the same technology as the Alps does other than it is a dye sublimation capable printer. Not all Alps printerers are Dye sub capable either. The basic print function of an alps is similar to a dot matrix printer. The print head passes over a ribon. When it is in the position for the image it has small pins that press down on the ribon and transfers the wax "ink" onto the paper. There is a small amount of heat involved but, no where near the amount needed to sublimate the "ink". The dye sub capable alps printers have a setting that allows the head temp to go higher when the dye sub inks are loaded. Unfortunatly the temps produced in dye sub mode are way too high for decal paper and will melt the carrier film creating a mess in the machine. The dye sub cannon machine uses a liquid ink that is sublimated onto the paper. How they are doing this is unclear to me as I have never messed with one.
The whole white ink issue is one that has been beat around on the web for years. I doubt that anyone is going to comercially produce a suitable white ink for the inkjet/laser market any time soon. The coment about someone producing it and making a killing is wishfull thinking at best. Think about the numbers. There are over 300,000,000 of us in the States alone. How many of that number do you think would want to buy a printer capable of printing white. The only ones I can think of are us Car, Plane, Truck, Wargame, Train, Etc modelers that want to produce their own decals. Maybe 100,000 of us and I think that is a fairly generous number. As a manufacturer I can't think that is a very enticing number.
Now lets get to the biggest problem with white ink for printers. It needs to opaque. The entire inkjet/laser industry has designed their equipment to work with transparent ink formulas over white paper. The technology to print white ink over a color is not there. The ink would have to be a heavy bodied material with enough fillers to make a solid opaque coating. This is the achillies heel of inkjets. They can't move that viscous a fluid thru the spray heads.
If, someday, this problem can be overcome, the next hurdle would be the driver software for the printers. The alps printers, with their unique printing method, have a feature that is imperative to printing a white layer under color s. It is the overlay feature. This feature allow the paper to be fed back into the machine in perfect registration so a second, third or more layers can be printed.