You might be thinking, “Printing is printing”, right? Well, yes and no. Printing processes are pretty much the same regardless of the material. You’re laying ink (or toner) on top of paper, cardboard, cloth, plastic or many other possible substrates.
However, as you can imagine, printing a T-shirt is quite a bit different than, say, printing a paper label.
In the world of printing, envelopes can present some unique challenges requiring some forethought and a bit of knowledge about how the process works in order to achieve the best result.
So, here are some of the most common errors. Try to avoid them if you can!
1.) Selecting or Assuming the Wrong Printing Process - As I’ve laid out in previous posts (see here and here) there are a number of different ways to print an envelope. Each method has its own unique characteristics as well as limitations. Factors such as the size of the envelope, the amount of colors and ink coverage and the quantity will tend to dictate the best process be it offset, litho, digital or flexo. For a complete explanation of each of those processes, click on either or both of the links at the beginning of this paragraph.
Two examples of how the wrong envelope printing process can lead to bad results are the heavy, dark ink solid and printing up to the window. On the former, some envelopes will feature a large area of solid dark ink. Maybe some copy is knocked out of the box, maybe not. If this type of a design is being printed on a stock envelope, it will most likely cause smudging on the back of the adjacent envelope. This happens as the envelopes come off the press onto the moving belt before they are put in the box. The heavily printed part can actually rub off a bit onto the back of the next envelope. The technical term for this is “offsetting”. An envelope like this either needs to have the solid portion cut back or lightened with a screen effect. If the heavy solid needs to stay, then the envelope will likely have to be printed on flat sheets and converted after the fact. This will add considerable cost to the job.
Printing right up to the window cut-out can only work if the job is converted after printing. If you want to print that design on a stock envelope, you have to leave a white border of at least 1/8” all around the window in order to account for print variation and to avoid ink on the window.
2.) Improper Design – Envelopes can be printed in a myriad of different ways with lots of color and coverage. However, sometimes the design that looks great on a computer screen will not be the most practical. One of the most common examples of this is the flap that is covered with ink right up to where it folds. That looks really sharp and it can definitely be done but there is a caveat. This type of design can only be accomplished by printing on a flat sheet and then converting into an envelope. The converting process includes some inevitable variation. This means that the ink on the flap will only hit the fold exactly about 20% of the time at the most. The rest of the envelopes will either show some white on the front or the ink will wrap over a bit to the back. That inconsistency is generally not anticipated by the customer. At Elite, we will always warn a customer about this in advance but that’s not always the case with other companies. The best way to avoid this is to design the ink coverage on the envelope flap to wrap around to the front of the envelope by ¼”. You’ll show some ink on the front but at least it will be consistent although still with a little variation.
Another common example of an impractical design is when heavy ink solids are placed on top of where the envelope folds or where the flap sits. Envelope presses rely on the pressure of rubber rollers to impart the ink and image. Because of the numerous folds in the back of an envelope, there is a slightly uneven surface on which to print. Placing a heavy coverage of ink, especially a dark color like blue directly over these uneven areas can result in small white lines through the printing. These are what’s known as “seam marks”. Moving that portion of the graphic image to another spot on the envelope or, as in #1 above, lightening the image with a screen effect can usually solve the problem.
In all cases, your best approach would be to deal with a company that specializes in envelopes who would be able to advise you on the best way to print your particular job.