Bleed (printing)

In printing, bleed refers to the portion of a printed image that extends beyond the final trim size of the page. It's an essential design consideration to prevent white edges from appearing along the edges of the finished product when the paper is cut to its final size.

Purpose:

The primary purpose of bleed is to ensure that any images, colors, or design elements intended to reach the edge of the printed piece do so completely, without leaving a visible unprinted border. This is because commercial printing processes can have slight variations in the cutting accuracy during the trimming phase.

How it Works:

During the design phase, images and colors are extended beyond the intended trim lines. This extra area, the bleed, provides a buffer for potential cutting inaccuracies. After printing, the printed sheets are trimmed down to the final desired size. Any slight misalignments during the cutting process will only remove the bleed area, leaving the desired edge-to-edge appearance.

Standard Bleed Size:

While specific bleed requirements can vary depending on the printer and the type of project, a common standard for bleed is 1/8 inch (0.125 inches or 3mm) on all sides. This means that images or colors should extend 1/8 inch beyond the trim lines of the document.

Consequences of Not Using Bleed:

If bleed is not used when designing a document that requires edge-to-edge printing, there is a high risk of thin white lines appearing along one or more edges of the finished piece after trimming. This can detract from the overall quality and professional appearance of the printed product.

Importance in Design Software:

Most professional design software (such as Adobe InDesign, Illustrator, and QuarkXPress) provides options for setting bleed margins when creating a new document. It is crucial to define these bleed settings at the beginning of the design process and to ensure that all relevant design elements extend into the bleed area.

Submitting Files to a Printer:

When submitting files to a commercial printer, it is essential to include the bleed in the final PDF or native file format. The printer will use this bleed information to properly prepare the file for printing and trimming. Clear communication with the printer regarding bleed requirements is always recommended.