Among the various printing methods employed by printing presses around the world, flexo printing and offset printing are quite popular. Both these methods of printing make use of good quality printing plates and wet ink. However, their printing technique differs. Flexo printing should be your first preference for a variety of materials as well as tasks while offset printing is suitable for several others. The amount of print outs you require also plays an important part in determining the suitable printing method. In this article, you will learn the key differences between flexo printing and offset printing methods. So, read on!
What is Flexo Printing?
In flexo printing method, the ink is directly transferred from the plate to the substrate. This printing technology is quite old but has seen improvisations over time. It is a reliable printing method that delivers high quality and ensures brilliant speed.
What is Offset Printing?
Offset printing makes use of a printing plate for transferring an image to an intermediate carrier which is a rubber blanket and thereafter to the substrate that needs to be printed. It uses a flat image carrier. It is a popular printing method mainly because it offers high print quality consistently and is comparatively economical too.
Key Differences between Flexo Printing and Offset Printing
Flexo and offset printing methods may appear similar because they make use of similar equipment for the purpose of printing; however the two are quite different from each other in terms of the techniques they employ. Here is a look at the key differences between flexo printing and offset printing to help you decide which one is more suitable for your task:
1. The Use of Ink
Process colours as well as spot colours come handy in flexo printing machines. Spot colours are usually pre-mixed however many printing presses mix them in-house too. Flexo inks are UV curable or water-based as well as solvent based. You can achieve higher running speed with UV inks. You don’t have to empty and clean the print station frequently when you use this ink. You can leave it inside the machine even when it is not in use however you cannot do the same with the water-based inks. It is essential to remove this type of ink from the press to avoid it from drying in the tray or on the roller when it is not in use.
Offset printing comprises four process colours including magenta, yellow, cyan and black. All these colours contain an exclusive printing station. The offset printing machines also make use of spot colours. Process colours are combined to create spot colours.
2. The Use of Printing Plates
Flexo printing machines make use of flexible plates made of photopolymer compound. Earlier, these plates were made of rubber. They wrap around the printing cylinder with ease and print the surface as they rotate at high speed. The image on the plate is fixed with a laser imagesetter and the ink is transferred via a rotating roller on the flexo plate. Thereafter, the image is printed to the substrate. The polymer in the non-print spaces washes away during the process. It dissolves into the water solution.
While using this method, you need to use a different flexo plate and printing station for each and every colour. However, the good news is that the plates are durable. You can re-use them multiple times before replacing them.
Offset printing machine transfers ink to the printing plate using a series of rollers. Thereafter, the image is transferred to a blanket and then to the substrate. The machine can use both rotary as well as flatbed processes for printing. The process depends on the type of offset press. The plates in an offset printing machine are usually made of aluminium and are quite durable.
3. Materials Suitable for Printing
Flexo printing method is apt for printing various kinds of materials. You can print absorbent as well as non-absorbent materials using this printing method. It works best on foil, fabric, thin films, cardboard, different kinds of metals, plastic and cellophane. It is suitable for any flexible surface. This is why sweet papers, label stock, retail bags and envelopes are printed using this method.
Offset printing method is best used on materials such as metal, paper, cardboard, vinyl and cellophane. However, unlike flexo printing here the surface should be flat to ensure smooth printing. Newspapers, magazines, books, brochures and other such items are printed using this method.
Which Method to Choose – Flexo or Offset?
You should choose the printing method depending on your particular need. Here are few points to help you choose one:
Flexo printing method is an ideal choice for long printing runs. It runs at high speed, prints different kinds of materials mentioned above and helps carry out additional tasks including varnishing, laminating and die cutting in one pass. The flexo printing machine is available at a cost-effective price and is low maintenance. Its printing plates are expensive in comparison to those used in other printing methods however they last long if you clean and maintain them properly. Offset printing plates also offer sharp, high quality images. Its printing plates are quite durable. They last long because they do not come directly in contact with the printing surface. Besides, this method of printing is quite economical. So, if you are low on budget then this method can be a good choice for you depending on the printing material.
We are sure this has given you a clear idea about how flexo printing and offset printing work and the factors that set them apart from each other. Both come with their own set of advantages and are suitable for different materials and purposes. You shall be able to determine which one is best suitable as per your need by going through the differences as well as the details about both these printing methods. Do let us know if you require further information regarding these methods or need help choosing among the two. We shall be glad to guide you.