PVC printing with blotchy spots?

[jmcnicoll]

Can anyone say what is causing this? Is it the board? Environment?

 

[Jack Knight1979]

board contamination.

 

[jmcnicoll]

Would that be in the board and can not be cleaned? We've tried cleaning with various liquids, and methods. Is it a manufacturing defect? Will we ever get rid of it?

Printing direct with AGFA Anapurna M.

 

[Gino]

That could be board contamination or happen even after it's done and you handle it too quickly.

We generally clean the board for dust and other solids and then we wipe it down with 91% alcohol before printing... even if they're masked.


The cheaper substrates tend to have more of these problems. When price means everything and you buy the cheapest.... you generally have more of this/these problems.

 

[jmcnicoll]

happening during printing, boards being dusted and wiped with denatured alcohol, but have tried 70% isopropyl as well. Seems to come in bunches.

Is it a manufacturing defect in the board? Will we ever get rid of it while printing with our agfa?

 

[WB]

we use 99% alcohol on our boards.. I find PVC's are the worse.

Also I don't spray the boards directly, I spray the towel and then wipe the boards.

 

[mygraphicsshop]

Also, make sure you are wearing latex or cotton gloves while handling the boards. This issue seems to happen to pvc and foamboards the most. Id assume due to their porousness.

 

[Gino]

91% is 20% better. Try it. It will make a huge difference.

We still get it from time to time, but the ink coverage usually covers it up. It generally only happens in our lighter colors. If you see it in your darker colors, you need to use more elbow grease for sure.

 

[miker]

We have the same issue. It is in the manufacturing process. Any extremely light coverage and it will come and go as it pleases. We usually just end up printing a layer of white ink.

Doesn't matter what brand or supplier. We buy full skids of 3mm and 6mm and we have it come and go randomly. Cleaning with alcohol can help but it can also leaves streaks that will show through light coverage.

 

[Jack Knight1979]

Frustrating isn't it. Seems like we cant catch a break. Expensive equipment, nice boards, pre-flight cleaning, still bad prints. doh.

 

[jmcnicoll]

Would you say this problem as gotten worse over the last few years, or has it always been a big issue?

 

[WYLDGFI]

We just had same type of issue on board today. Sucked...in the trash it went.

 

[Dave Rowland]

only profile i find that works best on board is
720 Double pass bi-dir 4pass on an Anapurna M2050
A single pass would not cover enough

 

[ezposter]

Try Palight

We switched to Palight which is masked and ultra white. Consistent output and quality. Piedmont Plastics sells it here.

 

[miker]

We switched to Palight which is masked and ultra white. Consistent output and quality. Piedmont Plastics sells it here.

We've tried that in the past on our gandi flatbed before we upgraded to the Vuteks. We found that removing the liner created a large amount of static that produced other print problems. Glad it is working for you.