A few things worth knowing and to consider when printing onto brown kraft paper board and uncoated paper board materials.
Kraft brown paper board and uncoated boards will impact the way that colours appear when printed. Lighter colours may not be very visible when printed whilst medium to heavy ink shades tend to appear darker. You can print a white background behind some colours to create a truer and more full colour which as always, is a subjective design decision.
The image below gives you an indication of how printed colour will appear on a Brown Kraft paper board stock both with and without a white base. The white base is the obvious way to keep the colours more full and vibrant, but applying a white base behind very fine detailed design can be tricky so you should ask repro and printer
for advice on this option.
There is another option worth consideration when printing without a white base and that is to print the product on a UV curing printing press. This means the ink is instantly cured and dried as soon as the ink is on the uncoated surface and therefore maintains more vibrancy on the uncoated surface.
Brown Kraft paper board is 100% recycled material and therefore the base brown colour can vary in its tones quite a lot throughout the material batch / print run. Imperfections will also be visible and this may impact the final print. These are things that are out of our control and are part of the use of Brown Kraft paper board.
Kraft paper is a natural texture – it is an uncoated card stock.
When printing on uncoated materials you should think of the material as textured and ‘absorbing like a sponge’ as the surface of the board is more porous because it is uncoated, so the printed ink soaks into the stock more. Colours will not appear as vibrant and fine detail cannot be held as well as they would if printed onto a coated paper board surface. This can vary a little, but as a guideline, the finest detail recommended on uncoated surfaces is 1pt line-weight