When Ink Is Not the Problem with Digital Printing, Part II

Beyond dust and dirt, several factors impact the ink’s ability to stick to the substrate. The carrier ­ aqueous-based or solvent-based ­ is another key factor in the final outcome. Then there’s calibration.

Discover media issues that could ruin an otherwise picture perfect print job.

Ink is pivotal to every printed image. After all, you can invest in a printer that costs multiple thousands of dollars, but if your ink is low-quality you won’t get maximum results.

By the same token, you can invest in a printer that costs multiple thousands of dollars and run into a major learning curve that sends your quality down the tubes. Or it could even be some simple calibration issues that lead you to less than desirable results.

But your high-dollar printer and your brand-named ink can’t bear all the reproach of poor quality prints ­ if you aren’t using the right media.

Indeed, as we discussed in part one of this article, your printer, ink and media have to be harmonized in order to get optimal outputs. With that said, it’s time to explore media issues that could ruin your otherwise picture perfect job.

“If your media is bad, your print is going to be bad ­ bottom line,” says Xerox digital imaging spokesperson Sandra Mauceli. “Optimizing the print has a lot to do with surface coatings, surface texture, how the media has been finished and even how the media has been cut. If you don’t cut the media correctly, you are going to end up with a lot of dust and dirt. That will hinder the ink’s ability to stick to the media for the long haul.”

Making Ink Stick
Beyond dust and dirt, several factors impact the ink’s ability to stick to the substrate. The carrier ­ whether water-based, aqueous-based or solvent-based ­ is another key factor in the final outcome.

“If you have the wrong carrier on the wrong media, your images could turn out blurry,” Mauceli explains. “Or if you have too much carrier and not enough ink, you could end up with light images. So choosing the right ink is more than just picking one that is compatible with your printer. The media also plays a critical role.”

Indeed, one of the biggest mistakes is using cheap media. Because there are so many new people in the industry and because they are struggling to compete and survive as they learn, a lot of people make the mistake of using cheaper vinyls and cheaper inks trying to use price as a market advantage to land business instead of relying on their own quality and service.

The inexperienced or overly frugal sign guy may try to work with products that are, in some cases, not suited to the application, like using calendared vinyl on vehicles. That’s a no-no. These guys don’t give themselves a fair shake if they are using the cheapest products. They probably end up wondering why they are having trouble. If you work with better products you’ll find that they cut easier and install easier.

Have You Calibrated Lately?
How does the ink look when you print it out? In terms of media, there are three factors that determine how ink appears on the final print: brightness, absorption and reflectance. These characteristics describe the media coatings receptiveness to ink.

Not to get too technical, but your RIP software needs data about the color properties of both your ink and your media so it can offer up the right instructions to the print engine. Without this information, you could wind up with too much ink or not enough ink getting jetted onto the substrate with each pass and have some of the problems Mauceli described. Either way, you are losing quality and in some cases you may have to file the printed image into the circular file.

It’s one thing for colors to look different on your computer screen than they do in print. But it’s quite another to print a second copy of the same file a month after the first and discover the colors look markedly different. If that happens, it’s a sign that you need to calibrate ­ or recalibrate, as it were, your printer.

Calibrating your printer helps align the various aspects of your system so that you can get optimal results. If you are saying to yourself, “Well, I’ve already done that. So I’m in good shape”, then here are some issues you may not have considered…

First, if your printheads are getting on the old side, they may not hold the calibration. Second, if your shop is in a humid region of the country, it could adversely affect your printheads. These are just a couple of the X-factors.

The good news is, your printer’s firmware or RIP software can make it an easy task. So don’t ignore this simple, yet potentially dramatic element of printing perfection.

Do You Have a Drying System?
This may sound like a stupid question, but if you don’t have a drying system, then you’ll be glad I asked. A drying system is generally a row of small fans. If you didn’t choose this option when you bought your wide-format printer, or if you didn’t even have the option, then just get some fans and make your own drying system. Why? I’m just about to tell you…

You can do everything in the world right. You can buy the right media, get the most expensive ink, calibrate your printer, and optimize your printheads. You can do it all and still ruin your print when it comes off the line wet.

When your print comes out, you need to make sure it doesn’t touch anything. Whatever you do, don’t roll it up prematurely. Let it dry for at least 30 minutes, preferably even longer, because the prints surface tends to be somewhat sticky.

Here’s another tip: Don’t print on the first foot or so of your media or you will wind up with some funky issues in the areas where the outer plastic wrap was taped to hold the roll in place. The tape strips the coating off the media and deters the ink from sticking to it.

Hands Off!
And if you haven’t already noticed, your fingerprints can do plenty of damage of their own, no matter how dry you think your hands are. Everybody’s skin has at least a little oil, whether you can feel it or not. Wear gloves when you handle your media so that you don’t wind up with spots where the ink doesn’t absorb properly.

Keep your shop clean, too. If your shop is dusty and dirty you can’t expect to get optimal results on your print. One way or another ­ either before the media makes its way through the printer or after it comes out wet ­ if your shop has dust flying around you are going to reduce the quality of the prints.

Finally, don’t put media through your printer that is curled up. Humidity can cause this phenomenon and this phenomenon can cause what’s known as a head strike. You don’t want to experience this because it can ruin your head and it could cost you hundreds of dollars to get a new one. Better to sacrifice a few feet of curled media than a printhead that will shut you down until you get a new one.

So, as you can see, there are definitely some ink issues, definitely some media issues, but absolutely some common sense issues, too. Of course, these common issues wouldn’t have made sense to you if no one told you. Now that you are equipped with this practical know-how, go ahead, start printing!

As seen on signindustry.com