When it comes to package printing, there are four main technologies utilized by printers and label makers: flexo, digital, gravure and offset.
This post is designed to focus on the key differences between flexo and offset, which are two of the most popular printing methods used in packaging when it comes to quality, consistency, and long-run printing jobs.
Flexo Printing vs Offset Printing: The Similarities
But before we get into the key differences, let's first take a look at the similarities between flexo and offset:
- Each involves the creation and use of a printing plate or other image carrier.
- Both processes work with wet inks.
- Both are able to print on a wide variety of substrates.
- Because of lengthy setup times and plate/ other image carrier creation, both processes are ideal for long-run jobs.
However, these two methods differ in process and various other factors.
Flexo Printing: The Basics
Flexo typically utilizes a polymer or elastomer image carrier such as sleeves, cylinders, and plates. The image carrier is engraved to create the raised design of the final desired print. Ink is then transferred from the inkwell via an anilox roller onto the image carrier, where it is then printed onto the substrate.
Flexo printing is more commonly associated with uses in flexible plastics and other non-porous materials such as film, labels, foil, and other packaging.
Offset Printing: The Basics
Offset also uses a plate, but it works in a different manner than flexo. Offset plates are usually made of metal, and the printing ink is transferred via the plate to a rubber piece of material (often this is called a "blanket") and then to the printing surface.
Offset is most commonly used to print on paper (think: newspapers and magazines), as a flat and smooth surface is required for printing.
Offset Printing vs Flexo Printing: Key Differences
There are a few additional factors where these two printing methods differ greatly.
Flexo is able to operate with many more types of inks.
Offset generally works with inks that are oil-based along with using some water-based and UV curable inks.
One thing to consider about offset is that the plates used in the process are susceptible to oxidation if they're not cared for properly. For this reason, extra maintenance is often necessary to ensure plate quality.
Flexo image carriers are generally a bit cheaper to create, and they also are typically more durable than the plates used for offset -- meaning they can be re-used a few times before replacement is necessary.
What's more is the wider range of inks that flexo works with (notably the faster drying times with low viscosity inks and UV inks) can accelerate print jobs and increase job profit.
As noted briefly above, offset printing can only be accomplished on a smooth, flat surface. Flexo, on the other hand, can print on a wide variety of substrates, making it a more convenient choice for many.
Combine this with Flexo’s ability to use many more types of ink and the ease of printing more large-scale tasks, it is often hailed as the superior choice.
So what process is right for you? It largely depends on the job, substrate and a variety of other factors of the job you're printing.