So, it has come to my attention that most of you have no clue as to who I am and more importantly, what I know about printing. There is too much to say and I don’t want to toot my own horn, so I will write this intro by way of discussing an issue or lack of one that has been popping up lately.
Is this ink cured?
There have been statements saying that you cannot over cure ink. In reality it depends on your definition.
Take a cake for example:
If you do everything correctly the cake is perfect. Moist, full of flavor, it’s good to eat.
Cook it a little too long and it is dry, has no flavor and although still eaten, not as good as if it was cooked correctly. Can you over cook a cake? Yes.
The same happens with ink. Very few ink issues are under cured. When an ink is under cured, it will fade away. That is the clue of under curing. Every other issue is “over curing”
You are technically correct in saying that the shirt would catch fire if you heated plastisol ink to the chemical level of over cure. However, like our cake, an ink can be over heated enough to not do what we want it to do.
Inks have 4 distinct temperature zones. These are not the correct names for these zones. They are what I use to help explain what they do.
Flash Point
Flash Gel
Cure Point
Cure Gel
The first and third are the goals.
The second and fourth are where we encounter problems.
Inks are built to have ranges of temperature that fall in each category. The “Gel” categories are where the problems arise. Each color as well as base has specific ranges. Back in the day, we had a “Flash” white and a “Finish” white. They were built to accomplish different things. The issue with using a “finish” white in the day was that the flash temp was too close to the flash temp of colors. The “flash” white was not bright enough and usually the printer would use the wrong white in the screen.
It is 100% about temperature environment control.
“Why” is the question we need to ask.
Why do we have the ink chemistry we have today?
Why do we need tight screens?
Why do I need to expose a screen for …?
Why is the ink doing this?
Why is the screen doing this?
Understanding where we were is crucial to understanding where we are.
These are some of the things that I teach when I come to your shop and train on “The Physics of Screen Printing” Trouble shooting the “Why”
There are a lot of other things I can train you on as well.
