This was again a custom requirement by one of the client based in Singapore who requested to add a print button in the document library’s display form ribbon to print the display form. And again I developed a custom feature in Visual Studio 2010 starting with an Empty SharePoint Project template.
created Image folder. If you do not have a 32x32 print icon then you may download it from here: http://www.softicons.com/free-icons/toolbar-icons/32x32-free-design-icons-by-aha-soft/print-icon
This will automatically add the print icon image to IMAGES folder of 14 hive