Bleed is one of the most important parts to design any attractive artwork for print. In this regard, Professional designers are using expand background images as well as elements beyond the ends of the text by using additional 3mm or more as per the requirement. It is also avoiding unnecessary white borders and side of the printed document.
For example if you had a document which had a solid background colour printing from edge to edge, to print it without bleed means that it only has to move a fraction of a millimetre and it will result in an unsightly slither on one or more edges.
A designer needs a few hours to design a masterpiece that looks and appears perfect on screen. But it’s a very poor final result if there is a tiny even less than 1mm white unprinted border around the edge.
Its not the printing which is the problem, it’s the awkward task which the guillotine operator has trying to cut the document to size, if this was being done on a single sheet using a scalpel, which is normally how the designer would proof it to their client. A guillotine trims 1000’s at a time, and there is no machine in the world which can avoid part of the pile of sheets having some movement, the tolerance can be up to 0.25mm.
To manage this problem, all print companies use a slightly bigger sheet paper to print your design and cut it with perfect measurement in the perfect size. In this regard, you can get some perfect design that you are looking for.
This extra is called ‘bleed’. When the deign is created its made slightly bigger than its needed, especially any background colurs or images which meet the edge of the page.
Alternatively we could print the whole document 1% larger in order to create bleed, but this tends to cause problems with important information which is close to the edge of the original page size, this can result in a messy final document which has altered the original design created by the designer.
So by adding the correct bleed this issue is resolved.
The designer needs to increase the edge of the document by 3mm on all edges. This means that an A5 document which is normally sized at 148.5mm wide x 210mm high, needs to be increased to 154.5mm wide x 216mm high. This is printed and then trimmed back to the original A5 size and therefore any movement on the guillotine is not noticed in the final printed sheets.
A word of warning however, if you are asked to re-supply artwork to include the bleed edge, its not always possible to just increase the document size to make up the bleed. As mentioned before this can cause the important elements of the design to run very close the edge of the trim, and in some cases be trimmed off all-together.
Ideally its best to keep important elements of your design at least 5mm away from the trim edge. This is only to avoid the design looking cramped and unprofessional but also increase the risk of image or text being lost when its trimmed.
Due to all the reasons mentioned above, the guillotine operator is required to know the perfect measurement and area of the sheet to cut up the paper. This they do by using ‘crop marks’ or ‘trim marks’ to indicate the edge of any printing documents. These are thin and short black lines are a visual reference for where the deign ends, especially a design with bleed, which will be difficult to see where the intended design finishes and where the bleed begins. Crop marks are usually placed slightly away from the bleed area, this is so they do not print. Crop marks which join together propose a similar problem to that of no bleed, if the document moves either on the press or on the guillotine then its likely the crop marks will be printed and show in the final design, so by offsetting them its possible to allow for tolerance in the movement of the paper.