The same surface spraying and printing, why are the final effects so different?

After working in the water cup industry for so long, I thought I would encounter fewer and fewer problems. Unexpectedly, I encountered another puzzling problem. At the same time, this problem also tortured me to death. Let me briefly talk about the content of this project. I hope experienced friends or colleagues can contact me professionally to help me clarify my doubts.

We undertook a customization project for a stainless steel water cup. The inside and outside of this water cup are made of 304 stainless steel. In one project, the customer’s quantity was divided into two. Half of the quantity was black on the surface, and the other half was white on the surface. The surface of the water cup is sprayed with powder of the same fineness. When the spraying was completed, all the processes could be described as perfect, and there were no problems. However, when it came time to print the customer’s logo, problems arose.

The customer chooses to print the black logo on the white water cup and the white logo on the black water cup. The first thing we printed was this sports water cup with a black surface. The process used was roll printing. As a result, problems arose. We printed multiple water cups repeatedly and debugged the printing machine many times, but the same problem could not be solved. He would say When printing white ink on the surface of a black water cup, there will always be a phenomenon of see-through. In severe cases, it makes people feel that the customer’s logo is incomplete. Even if it is slightly, it feels like the logo has been washed. In order to achieve the effect that the customer needs, in order to reflect For perfect results, the roller printing machine was debugged for 6 hours. In the end, the roller printing master had to admit that this process was not suitable for printing on this water cup and needed to be changed to pad printing. Sure enough, after switching to the pad printing process, many achieved the results that customers wanted. Seeing this, everyone must have thought that the story ends here. There is nothing special about this story, but it is not over yet.

After the black water cup was printed, we started printing the white water cup. Since the effect of pad printing on the black color was satisfactory, and roller printing could not solve the printing problem, we naturally still used pad printing when printing the white water cup. Technology, as a result, a problem arises. The printing process that shows perfect printing effects on black water cups cannot be realized on white water cups no matter what. The bottom-through phenomenon is more serious than when black water cups are roller-printed. Some water cups even need to be printed 7 , 8 times can be used to ensure that the bottom is not see-through, but due to too many times of printing, the logo was seriously deformed, which suddenly confused the printing master. He thought inertly, and it was confirmed before that the roller printing could not be used, and the pad printing did not work, so he changed the water The sticker can indeed achieve the effect that the customer needs, but neither the cost nor the production efficiency can be satisfied by this project. We kept trying, over and over again, for nearly 6 hours, but the difference is that the problem has never been solved. .

Having said that, among the readers who have read our article, are there any experts who can give some advice as to why this happens?

The black changing process has been solved, can the white changing process be solved? Black can be changed from roller printing to pad printing, but can white be changed from pad printing to roller printing? Although the printing master said it could be solved in this way, we were still quite uneasy when doing it. I won’t go into details about the process, but in the end the problem was solved perfectly. But I still want to ask everyone for advice. I hope friends with experience can share it.