We encourage our customers to be creative with their art! It's always exciting to see new and different techniques that create awesome designs. We also understand the restrictions of printing on bags.

You want your customer’s bags to look great, so having the knowledge to properly evaluate designs is very important. Below are tips for properly preparing art, and common errors that cause printing issues that may require revisions. 

Simplify designs

Avoid small details, small fonts, thin lines, and gradients. We print halftones at 35 LPI, which results in fairly sizable dots when printed. For larger images this can work fine, but lines, fonts, and intricate designs generally won’t look very good with halftones.

Plastic bags are printed with Flexographic plates – similar to thin rubber stamps mounted on cylinders. Because of the non-porous nature of plastic film and elasticity of flexographic plates, ink tends to spread more than it would when printing paper. Because of dot gain and the large line screen, halftoned text can be difficult to read.

Thin straight lines less than 0.5pt can develop bends and wiggles as the plate hits the film. Areas with small details can blend together. The subtlety of complex gradients and drop shadows can become completely lost.

To prevent issues, keep longer lines at 1pt width or wider and shorter lines (under an inch) to no thinner than 0.5pt. If at all possible, convert gradient images to a solid color, and avoid drop shadows.

Choose colors wisely

On white film, all colors print very well, but most inks darken significantly on colored films. Results can be hard to predict and can’t be guaranteed.

Most inks are somewhat transparent, so the film color shows through, basically combining the two colors. Color matching on colored film is very difficult; especially on darker films. 

We only guarantee matching the color of the ink, not the color of the final print. If you have questions about specific color combination, please contact us, we’re happy to provide guidance.

Trapping and Color Order

For jobs with multiple colors, consider the areas where ink colors touch, and the order the inks will be applied. The lightest color always print first and darker colors always print last. We recommend a minimum trap between colors of at least 4pt (1/16”).

As plastic film is printed, it stretchs and slips slightly between print cylindars, causing alignment of colors to shift slightly.  Adding as much trap as possible will keep your art looking good, even if it does shift.

Trapping issues can be avoided by adding a white (or knockout) border between colors so that no colors touch.

Save on Printing Plates

Save $$$ on plates by smart sizing – When creating art, keep plate size in mind. Plates can get expensive, and are charged in full square inches. Sizes are rounded up to the next full inch. To get the most for your money, size art in full 1” increments. This can become costly on larger plates.  For instance, if art is sized at dimensions are 10.1” x 20.1”, instead of 10”x20”, plates are charged at 11” x 21” – adding over 30 square inches! 

Don’t judge the size of the art based on looks alone. Adjust sizes of different design elements, or use less space between lines of text.  We can usually resize art at no charge.

File Formats and Submitting Art

To make the art approval process as smooth as possible, save time on revisions, and to make sure your art prints correctly, follow a few simple rules. Pass this information on to the your designer or whoever is preparing your art.

Submit art as a vector drawing in one of the following file formats listed below.

• PDF – Unlocked
• AI – Adobe Illustrator version CS5 or earlier
• EPS
• CDR – Corel Draw version X5 or earlier

Convert all lines and fonts to outlined objects.  Lines defined in point sizes are commonly used to create borders or to make fonts bolder. White lines can be used as borders to separate one area of art from another. Before submitting art, it’s important to convert these lines to outlined objects.  

Different design programs handle outlines differently; especially with dashed or dotted lines, corner angles, and size scaling. Converting lines to objects ensures that your art will print as designed.  Outlines can also affect the size of your art, as dimensions may be calculated based on the center of the line, instead of on the outside edge of the line.

Fonts should also be converted to objects. If we don’t have the fonts used on your art, text will display incorrectly. Even a font with the same name could have differences in spacing or character shapes.

• Convert Fonts to Outlines:
  • Illustrator – select text, from Type menu select “Create Outlines”
  • Corel Draw – Select text, from Arrange menu, “Convert to Curves”.
• How to convert lines (strokes) to outlined objects:
  • Illustrator – select object, from Object menu select “Path” and then “Outline Stroke”
  • Corel Draw – Select object, from Arrange menu select “Convert Outline to Object.”

Don’t include bitmap images if at all possible. Convert bitmapped images to vector format if possible. Bitmaps can be included in PDF, EPS, AI, and CDR files, but that doesn’t convert them to vector format. Please see our FAQ page for more information.

Converting bitmaps to vector images can be tricky, and is best left to professional designers. Results from tracing programs vary – straight lines can become curved, corners rounded, and round areas can become squares. Designers use a combination of tracing and drawing to convert bitmaps to vector images. If you don’t have access to original vector art, we can convert bitmaps to vector format for you, but we do charge an art fee for that service.