We provide customers with a preview of the bag with their graphics for approval before production. We place the graphics on the bag template and send it in .pdf for confirmation. All free of charge. However, we have customers who want to place the graphics into the template themselves. This is of course possible, just a few placement rules need to be followed.

We print 2 cm from the edge

When placing the preview, it is necessary to maintain a distance from the edges and bottom of the bag, at least 2 cm.

Template with guides – margins from the sides and bottom of the bag
The templates have predefined guides showing the printable area

From the top of the bag, a distance of approximately 7–9 cm must be maintained. This is due to handle adhesions, see photos below. Not all bags have handle adhesions, but for example bags with cotton handles finished with knots create bumps when printing on the bag, so the graphics need to be moved lower.

Glued handle patches inside an ExtraTWIST bag
Handle adhesion inside the bag
Template with guides – margin from the top edge of the bag
Guides are only displayed in the latest versions of Illustrator from the .AI file

Positioning preview over bag fold

The bag fold is the place where it is bent for folding the bottom on the back side. With silkscreen, where the bag is unfolded and placed on the printing palette, this doesn't matter. However, it's different with flexography, where the bag is printed folded. The cylinders in flexography roll over the (bumps) fold of the bag, and it's precisely in these places where the print may be imperfect.

Mounting a bag on a screen printing pallet
Inserting bag onto printing palette for silkscreen
Bag mounted on a screen printing pallet
Bag on silkscreen
Feeding a folded bag into a flexographic printing machine
Loading the bag into the flexographic printing press. Here, the bag is fed into the press whilst folded.
Folds of a paper bag
Example of bag folds (creases)

In flexographic printing, therefore, we position the artwork on the stencil so that it encroaches as little as possible on these folds. With flexographic printing on the reverse side, the print area is limited due to the bag’s gusseted base. We position designs on the reverse side of the bags above the folded base; see the previous article on flexo printing here.

Double-sided printing on laminated bags

Glossy laminated bags must be heat-sealed after printing, otherwise the print would be scraped off the slippery surface. The bags pass through a heat-sealing machine whilst folded. The rear side is exposed to a sufficient temperature for heat-sealing, but problems can arise at the folded base of the bag. The temperature may not always reach this area sufficiently, meaning the ink may not be fully heat-sealed. Although this is a rather rare occurrence, we prefer to avoid this area.

Laminated bags on the conveyor of the curing oven
Bags are placed on the belt and pass through the oven.
Detail of the fold on the back of a Pálava bag
Detail of the bag where you can see the small space in the fold of the bag on the back side, where it is difficult to get sufficient temperature for baking.

Conclusion

We check the submitted artwork from customers in our template to ensure they follow these three basic rules. If necessary, we adjust them and send them for approval. We will send you the template for a specific bag upon request by email.