6 Factors to affect Printed Image and its Quality in Offset Printing
When discussing offset printing, you will find printing engineers often involved in the debate about the factors that influence the final output achieved by a particular printing method. Most of the time, this discussion focuses on the relevant press and the printing process since this is where all the components required in the printing come together. There are a number of factors in offset printing machines, which influence the final print results. All the necessary components like printing plates, ink and substrate have a considerable impact on the final upshots.
How is print quality influenced by offset printing press?
The print quality does not depend on a single factor. Instead, there are so many factors associated with the cause. Some of them are listed below:
1. Register-defined printed image
Precisely align the inks printed in the production units to ensure register accuracy during the printing course, in the case of a detailed printed image that has to be printed in the exact position throughout the run. Remember, register differences may result in color variations.
2. Color fluctuations
Unlike other printing methods, offset printing is more vulnerable to color fluctuations and therefore need to be minimized during the production process. Color fluctuations are basically a result of all the parameters that can disturb the balance between ink and damping medium. To achieve desirable end results, it is important to have all the settings precise in the printing unit and must be checked on a regular basis.
3. Low dot gain
Go with a lower dot gain in the production run to achieve a larger range of tonal values that can be reproduced. You can reduce dot gain on the press through a number of ways, including the precise setting of rollers; correct unrolling of printing cylinders and optimizing printing pressure adjustment. Materials like blanket, inks, printing plates and the substrate can also hamper the end results.
4. No image slur
Production units must not result in image slur as it further causes dot gain and color variations in the printed image. Image slur is typically the transfer between blanket cylinders and plate that must always take place at the same position.
5. Ghosting
The printed image must not be prone to any reactions including the transfer of ink from the rollers to the printed paper. The setting of the wetting unit, as well as the amount of wetting medium also, plays a vital role in the printing process.
6. High reproducibility
High reproducibility determines how quickly the exact colors (just like the original image) in the printed image can be attained or how quickly the coloring as for the first print can be attained with repeated jobs. Many offset printing machines have automatic functions to simplify the process. Some of them include the inking-up program, ink zone remote control, ink/water profiles, stored color profiles, etc.
These are some of the points that influence the image and its quality. This is why; the materials needed in the printing process must precisely coordinate with each other.