Glass promotional mugsare a really fun way to add a interesting twist on an old marketing standby. Everyone knows about the promotional mug, they are very popular at the office and a great thing to give out at company events or even non-company events where you are looking to a drum up some publicity.
Because promotional mugs are so unbelievably popular adding a new twist is a great way to bring visibility to a product that may be overlooked by some people due to the fact that they are used to seeing them in large numbers.
Since a product like promotional mugs, however while the mug is sitting on a shelf overly busy graphics will become unreadable.
To avoid both of these problems on your glass promotional mugs you're going to want to keep the graphics simple and the color palettes minimal. Printing an actual background to help with the visibility of your graphics is a bad idea because it works against the entire reason why you chose glass promotional mugs in the first place; that is to say the glass clarity.
