Printability Adjustment of Printing Materials III

Printing plate

When discussing printing plates, it is necessary to separate the printing of the carton from the printing of labels, flexo packages, and corrugated cardboard. The overall trend is to use thinner plate systems in order to improve the printability of inks and substrates.

In flexo printing, the pressure setting is often higher than the pressure in pressure-sensitive printing. Therefore, the deformation of the photosensitive resin plate in the Enamel Plate is unavoidable, resulting in a relatively large dot gain value and the necessity of changing the plate. In order to improve the resolution of the outlets, reduce the spread of outlets, and increase the operating speed of machines, thin plates are now widely used for printing.

In order to obtain an acceptable printing effect, some kind of printing plate system is currently selected as a standard in order to ensure that the printability of the printing material is improved, and that the ink achieves the best performance.

Print on corrugated cardboard

This field has always been the focus of discussion. Here is a brief introduction of a standard plate system for corrugated board printing. This system can provide ideal printing properties.

Printing on Kraft/Whiteboard (B-Watts)

In order to reduce the dot gain when printing on corrugated cardboard, to obtain the appropriate printability, and to save costs, it is necessary to install a 3.94 mm (0.155 inch) thick plate on the backing paper, and then install them on the On the printer pressurizes the liner. Some printers mount the plate directly on the bracket. Plates of this thickness are commonly used on brownboards with a corrugation thickness of 1.5 mm (0.059 in.) to 3 mm (0.118 in.). The adjustment of the plates depends not only on the weight of the paper, the structure of the surface, and the quality of the backing material. , but also consider the structure of the printing press. There are a variety of printing plates, tapes, and holders on the market that vary in thickness, compressibility, and hardness. Commonly used are plates with a thickness of 3.94 mm and a hardness of 32-34 Sh°A or 40-42 Sh°A. More and more printers now prefer to use harder and thinner photosensitive polyester panels and place them on a special bracket that provides high compressibility. The market needs higher definition prints, lower dot gain rates, and easier handling and installation of photosensitive polyester panels, but the printing pressure must be set carefully, or the corrugations will be flattened.

Coated/Semi-Coated Paperboard (E-Watts)

Printing on coated and semi-coated white paperboard material (180-220 g/m2, E-Watt) using a thinner plate with a thickness of 2.84 mm (0.111 in) or 2.54 mm (0.1 in) )between. The hardness is 44-46 Sh°A, the dot gain is low, and the UPC code can be successfully generated. Modern printing presses reduce the part of the roll above the surface of the roll, which is particularly suitable for this thin plate technology. They have even become popular in Southeast Asia and China. In order to make full use of this thinner photosensitive polyester plate system, it is recommended to mount the plate directly on the adjustable bracket system. The adjustability of the stent is provided by an open polyurethane foam that absorbs the printing pressure and automatically reduces the pressure on the image on the photopolymer plate, resulting in a higher definition of the print. There are many types of adjustable brackets. The mixing of the plate hardness and the type of foam support has a major influence on the final print result, and the different combinations may vary in compressibility, thickness, cartridge grip, and PU foam stand stiffness. It is therefore very important to carefully test the performance of different combinations before changing the system or upgrading. If special printing characteristics or need to improve printability, it is recommended to invite manufacturers of printing plates, inks, tapes, brackets or corrugated papers to conduct joint medical consultations to discuss solutions.

in conclusion:

The printability is determined by the quality of the printing material used, the quality of the printing ink, the metal cylinder, the machine parameters and the printing plate system consisting of a photosensitive polyester plate and an adjustable support.