Speaking of glass printing, with the rapid development of technology, it is no longer a simple black matrix + LOGO, many novel designs can be realized.
When you get the finished product, it may seem simple from appearance, but in fact it is the hard work of the printing masters for half a month.
I guess that our fellows also feel the same way about the glass panels.
These are really headache for many printers, like “white,” “silver,” “red,” “colorless” .Finally finished the samples, the customer said “with the original sample color difference”, “ink is easy to peel off”…… It’s always in trouble during sampling.
Printing Difficulties at A Glance
- White
The whole side white printing is quite challenging.First of all, after receiving customers’ drawings, do NOT to print at once,please ask customers’ detailed requires for white printing. For example, apple white, cold white, warm white, or let the customer provide a piece of other accessories to match the color.
Secondly, soda lime glass is not suitable for printing white. Because the glass has a greenish tint, and the white edge will also show green, easily to be not accepted by customers. So low iron glass/aluminosilicate glass + white printing solution should be recommended at the beginning of the project evaluation.
Thirdly, white belongs to the semi-transparent ink, and it cannot be printed 2 layers like black.Usually we print 3 times white + 1 time gray printing to make sure its high opacity. Sometimes,even 4 times white + 1 time gray printing are needed according to customers’ requirements.
Finally, there is the problem of white color difference. Film thickness, ink consistency and the difference in the ratio of each batch of ink affects ink color.These are the most difficult to control. It is recommended to control with a chroma meter.(Our model no. is Konica Minolta CR-400)
- Semi-transparent ink series
Example 1: Red, which is a kind of semi-transparent ink , and like white, is easy to produce black and white dots, debris, and color differences during the printing. This color is an eye-catching color, and easily to be found these defects visually.
If it is a small area of LOGO printing, the yield rate is relatively easy to be controlled. However if it is a large area or frame printing, the requirements for a dust-free environment are quite strict.In addition, this semi-transparent ink also required to add one more layer, usually white layer will not affect the brightness of the color.
Example 2: Semi-transparent black (Dead Front Effect)
It can be realized through printing within 30*30mm. For larger areas, it is recommended to use “gray-glass one” Black” (For more introduction, please click the link:
https://www.gelivableglass.com.cn/help/201912249412510.html
- Metal Series Ink
“Easy to peel off” is the fatal weakness of metal series ink.
Silver and mirror silver are the most common metal ink, even if it is a small LOGO, the metal ink will peel off after ultrasonic cleaning, not to mention large area printing.
Our solution is to print a layer of varnish on the back, so that the ink is safe and won’t fall off.
These are some difficult printings. Whether you encounter them or not, it is recommended to collect them first, and it’ll be helpful when you meet these issues in the future. Please follow us, and leave a message if any interested.