- High Quality: Due to the print process, offset print produces the sharpest images making it ideal for color accuracy or those looking for high-quality print.
- Cost-Effectiveness for Large Runs: While the initial setup costs can be high, offset printing becomes cost-effective for large production runs due to its ability to produce high volumes quickly and efficiently after the original print plate is produced.
- Versatility: Offset print is flexible to accommodate a variety of substrates making it suitable for various packaging types, such as boxes, labels, and cartons.
- Consistent Color: Offset printing is able to accommodate spot colors and therefore will allow for the most precise color matching to ensure consistency across multiple print runs, which is crucial for branding.
- Accommodates Many Inks and Finishes: Offset printing allows for the use of a wide variety of inks, such as eco-friendly options. It also allows for many finishes and enhancements, such as adding UV coatings, which you may want to take advantage of to spruce up your packaging.
Offset Printing
What is offset printing?
Offset printing is a printing technique that allows for the highest quality output. Offset printing, also called lithography or offset-litho, is a printing process where ink is transferred from a metal plate to a rubber sheet, which is then rolled onto the substrate paper. Offset printing includes 3 layers of material, 2 of which are printed on and 'laminated' (glued) onto either sides of the third.
- Substrate (outside layer that is printed on)
- Corrugated cardboard (board + fluting)
- Substrate (inside layer that is printed on)
Ink rollers along with water rollers help transfer the ink onto the printing plate which then transfers it onto the substrate. This layer is then laminated (e.g. glued) to the corrugated board. Offset printers usually have ink in the CMYK color system, and using the CMYK color system would require 4 plates, one for each of the CMYK colors. Offset printers can also work with PMS colors and combinations.
Printing on a smooth substrate as opposed to corrugated cardboard results in higher quality print. The downside, though, is that it makes the box a bit thicker/heavier given the layers. Generally, offset printing is suitable for large printing jobs and the price tends to go down with the increase in the number of printing jobs. Offset printing also yields the highest quality print in terms of color, sharpness, and crispness, making it a great choice for those looking to create exceptional packaging.
To learn more about other types of printing for packaging, check out digital printing or flexographic printing.
Offset Printing Process
1. Design preparation: Packaging designs are made using graphic design software and checked for offset printing specifications such as color separations and bleeds.
2. Plate Production: Printing plates are produced by transferring designs to large plates (often aluminum) using chemical processes or computer-to-plate technology.
3. Print Press Setup: The offset printer is set up including the mounting of print plates and adjusting the printer’s ink settings according to the chosen substrate to ensure correct color output.
4. Ink Preparation: Depending on if you will be using processed or spot colors, the ink will be prepared to ensure any custom colors are accurate.
5. Printing: During the print process, ink is applied to the metal plate which transfers the image to a rubber blanket. When the substrate is passed through the press, this rubber blanket then transfers the ink onto the substrate. Each print tower is only able to print one color, therefore this process is repeated for every color required. In the case of CMYK coloring, the substrate will repeat this process with the 4 colors of cyan, magenta, yellow, and black (key). During this process, quality control occurs to ensure the color and print remain consistent and accurate with adjustments being made as needed.
6. Drying: After printing, the ink dried quickly either through air drying or using a UV light depending on the ink used.
7. Finishes: After printing, the packaging may undergo any other finishing processes such as die-cutting, folding, laminating, foil-stamping, or any other additions needed.
