When you buy a card printing machine to make cards for ID or security purposes, you must consider some technical aspects of the machine before you make a decision. Each of these factors plays an important role in how you print cards and for what you can use them.
Security cards often have magnetic stripes and tags that are placed on the card to provide a unique identification number. You can find out about Machine Sales via Inkjet Monkey.
These numbers are attached to certain people and are loaded into a central security system where their access is monitored for attendance and keeping time.
The access system also controls which IDs can enter certain areas of the complex. Is that just for the front gate to housing or is it limited access for IT people in their own department to give a few examples.
If you plan to print images on your card you will need a resolution that is good enough to make sure the image comes out clear and visible. 300dpi is standard on most printers today, but you can buy higher resolution or variable ones.
Printed images and text use thermal transfer resin and dye sublimation to burn images and words onto the surface of the card. You might want to consider printing on PVC cards or polyester cards because they are durable and can have a security tag for ID purposes.