How to Prepare Print-Ready Files for Custom Packaging

Getting your print-ready files for custom packaging right the first time saves you money and avoids the pain of reprinting. A print-ready packaging file means the artwork that was already reviewed and compared to the dieline, exact dimensions, color separation, and finishing of the packaging manufacturing. Missing one of these details will mean having problems with your box not folding right, having poor colors, or even misplacement of your graphics. 

Set Up Your Packaging Artwork Correctly

Before handling the dieline or considering bleeding, the creation of the art needs to be done properly. This is the step where many designers neglect, and this is also where reprints begin.

• Use the Correct Color Mode

Packaging printing runs on CMYK instead of RGB. RGB is designed to be used for monitors, and once a printer tries to convert an RGB file to a CMYK file at the last moment, there is a possibility that the colors would change. Set your file to CMYK from the start so what you see on your monitor is closer to what actually comes off the press.

If the branding of your company depends on a certain color, like a special blue or shade of red. Check with the printer if they are able to use Pantone or spot colors on your project. Using spot colors will help you ensure the consistency of the result when using CMYK is not enough. 

Do not forget that you should never send your work to the printer in RGB format. It is the quickest way to get yourself into trouble. It is important for packaging projects because of their specific requirements for large solid color areas, backgrounds, and gradients.

• Use 300 PPI Images

Any raster image in your packaging design file, product images, textures, and logos that have not been vectorized need to be a minimum of 300 PPI in their final printed form.  Not 300 PPI when it was originally shot and then stretched larger, but 300 PPI in their final printed form.

Images which may appear nice on the computer monitor when they are lower resolution will become fuzzy and pixelated once they are scaled up to fill a box panel. Make sure that each of your images is at 100% zoom and evaluate whether or not it is sharp enough for printing before exporting your designs. 

This is true for any stock photography and product images supplied by clients, because many times they were originally taken for use on a website and are only 72 PPI in size.

• Set Correct Line Thickness

Fine lines and thin strokes can disappear or print inconsistently when not thick enough for the printing press to grab onto properly. Try to keep all strokes at least 0.25 pt thick as a rule of thumb unless the specification sheet from your printer says otherwise. 

Lines used for decoration, thin strokes in letters, and thin border decorations are the usual culprits, so it is worth a quick scan through your file specifically looking for anything that thin. 

Work with the Packaging Dieline

The dieline is your printer’s guide to cutting and folding your box. There is nothing more important in the file than that. 

• Use the Manufacturer’s Exact Dieline

Never resize, stretch, or eyeball-adjust the dieline your manufacturer has provided to you. It was designed according to the cutting machines they use and according to the structure of your specific box. So a slight adjustment can affect your box’s folding and closing. You need to align your artwork according to the template they gave you, panel by panel. 

Do not try to modify the dieline your manufacturer has sent to you in case you need to make some size or structure adjustments; instead, request a new one. It takes a little more time, but it is much cheaper. 

• Keep the Dieline on a Separate Layer

The dieline should live on its own layer without being flattened and must be named with something simple like Dieline. This will make it easier for the printer to switch it on to view alignment or turn it off when viewing the artwork separately. Keeping the dieline within a design layer that has been flattened will only create difficulties in the process. 

• Separate Special Finishes

Each speciality finishing technique requires its own separate layer that is clearly defined to ensure that nothing goes unnoticed. These include:

• Foil Stamping
• Embossing/Debossing
• Spot UV
• And any other specialty finishing that your box requires

This ensures that each specific finishing technique used on your box is clearly visible without the printer having to guess where to apply them.  

Add Bleed and Safe Zones

Bleed and safe zones exist because cutting is not always perfectly precise, and this section is where a lot of “almost right” files fall apart.

• Set the Correct Bleed

Bleed is additional artwork going beyond the trim line so that in case there is a small movement in the cutting process, you will not have a thin white strip in place of the supposed artwork. Create an extension of your background and full bleed artwork by 3 mm beyond the cut line, which is common for most packaging projects, though make sure to double-check with the printer beforehand. 

The cutting machine for custom packaging is more demanding than a regular guillotine cutting machine, and die-cut structures requiring multiple folds are especially sensitive to it.

• Keep Important Elements Inside the Safe Zone

The safe zone keeps the inner parts safe while bleed covers your borders. The items to be kept away from trim lines, folds, glue sections, and other structural sections of the box include:

• Logo
• Text
• Product information
• Barcodes

Any items put close to folds or glued flaps run the risk of being cut off or distorted when the box is folded up. Running a simple check for each text or logo in relation to the safe zone guidelines is sufficient to avoid this problem.

Outline Fonts

Make sure that you outline all of the fonts in your document before you submit it. You will be turning your fonts into vector graphics that are not live anymore. The software on the printer’s end will no longer need the correct font in order to display your file. 

• Embed or Package Linked Images

When your design program uses a linking system for the images rather than importing the images within the design itself, ensure that all of these images travel along with the file when it comes time to export. The result can be a box or nothing at all without a certain linked image. This is definitely something you do not want to discover midway through the printing process. This type of function exists in almost any design program.

Export the Final Print-Ready File

The final document should be exported with proper dimensions, bleed, color mode, dieline, font usage, and finishing information to facilitate accurate printing and packaging.

• Choose the Correct File Format

The PDF document at high resolution will be most preferred by manufacturers because this format retains your layers, colors, and dimensions as well as is convenient to view. Certain manufacturers may require an AI document if they have to make any changes to the dieline design. Always confirm which format your specific printer wants before you export.

Use your design software’s print or press-quality export preset when exporting a PDF rather than the standard web export. These presets typically preserve CMYK values, embed fonts and images automatically, and keep crop marks intact.

• Check Bleed, Crop Marks, and Artwork Before Export

Before you hit export, run through the file one more time and verify:   

• Correct dimensions
• CMYK or Pantone colors set up properly
• Bleed extended correctly
• Dieline present and aligned
• Fonts outlined
• Images embedded or packaged
• Finishing layers separated and labeled

Catching an issue here takes a few extra minutes. Catching it after the file is already at the printer costs a lot more.

Print-Ready Packaging File Checklist

Before sending out your file for printing, here is the checklist that will allow you to double-check everything one last time. All issues with delivery, delays, and additional prints in customized packaging arise from the neglect of one of these points.

• Correct dieline and dimensions
• CMYK/Pantone colors settings
• 300 PPI images
• Sufficient line weight
• 3 mm bleed or as specified by the printer
• Safe zones are honored
• Dieline on separate layer
• Layers of finishing are on separate layers
• Outlining fonts
• Embedding images or packaging them
• Exporting a press-ready PDF file

Going through this list before every file submission will be the easiest way to prevent delays, unexpected expenses, and misprints in your design.