I am in the process of developing some digital scrapbooking pages. Am I able to copy images of the plaids to use as background "paper" or embed into objects (embellishments) such as a thistle design I created without copyright infringement?

I checked the Scottish Tartan Registry very thoroughly looking to see if there was any statement to this effect, since digital scrapbooking has some very specific regulations regarding digital scrapbooking copyright infringement. I have spent many hours trying to find specific information and thought this forum might be helpful.