All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad is His slave and Messenger. We ask Allaah to exalt his mention as well as that of his family and all his companions.
There is no harm in inviting people with the use of invitation cards provided these cards do not contain pictures of living creatures or other forbidden things.
Allaah Knows best.