Three Problems Frequently Occurring in the Printing of Tinplate and Their Solutions

The following problems occur in tinplate printing:

1. The accuracy of overprinting of printed products is not critical to product quality. With the application of multi-color printing presses, higher requirements are imposed on the accuracy of overprinting, even if partial overprinting is not allowed, the quality of the prints will be affected. The overprint error of the printed version, the deformation of the plate, the irrationality of the cylinder liner, the poor quality of the blanket, the poor elasticity, and the possibility of deformation; Improper adjustment of the printing machine, poor precision of the machine parts, etc. may cause overprinting. Not allowed.
According to the requirements of India Railway, the first printing plate must have a positioning crosshair, and the crosshairs of the printing plate are coincident with this crosshair. The following principles should be mastered when adjusting:

(1) The positioning force is able to stretch and fall, which is easy to adjust;
(2) The position of the printing plate to adjust the direction and how much to seek consistency;
(3) Schools shall adopt the method of loosening and pulling less to prevent the disadvantages of separation or deformation caused by excessive force when the printing plate is adjusted;
(4) The adjustment range of the printing plate should be advanced so that it can leave allowance for the printing plate and the roller attachment;
(5) The regulation of the side rules should grasp two points: First, according to the thickness of the tinplate, the size of the spring force should be properly adjusted; second, the distance between the rules and the tinplate should be generally 4-5 mm.

2. The solution of sticking phenomenon between tinplate and rubber roller when full-size products are printed:
(1) Reduce the viscosity of the ink and add some varnish.
(2) Check if the tinplate and printing pressure are reasonable.
(3) Adjust the proper speed of the printing machine.
(4) control the amount of ink.

3, the imprint is not correct, the solution to the phenomenon of lightening:
(1) Check whether the blankets, cushions are reasonable or have changes and displacement phenomena;
(2) control the layout of water consumption;
(3) Appropriate adjustment of the amount of ink delivery;
(4) Check the printing plate for the ink adsorption and the formation of the remaining ink layer.

Reprinted from: Chen Yi