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Why is ink and media combination so important? Ink “globbing”

Issue #0931/1 – Inkjet printer manufacturers are always going on about how important it is to use their own original supplies in our inkjet (or laser) printers. But, do we take any notice of them? After all, ink is just ‘coloured water’ isn’t it? And, photo papers aren’t that different are they? Right?? Wrong!! This article looks at just one implication of ink and media mismatch that will seriously damage a user’s pocket and ‘health’ (mental).

So why? What is this “globbing”?

Full image - matched ink and mediaImage as it should be with matched ink and media

Inkjet photo paper comes in two basic compositions but every paper formulation is different and printer manufacturers spend a great deal of time and money developing the chemistry of their inks and papers to make sure that they complement one another perfectly and react to one another in the best possible way. It is rather like strawberries and cream or what marriage is supposed to be.

As soon as this perfect combination is disturbed in any way, the balance is destroyed and the relationship fails – rather like oil and water or Britney Spears and Jason Alexander (marriage dissolved after only 55 hours!).

“Ink globbing” is my terminology for what can happen when a disastrously mismatched ink set and glossy photo paper are used together. It means that the ink effectively coagulates into globules on the surface of the paper, resulting in an image that is neither attractive, nor accurate. And, just to make matters worse, because of the nature of the fault, the ink does not dry quickly enough, resulting in severe transfer of the ink from the front of one photo to the back of another as they are deposited in to the output tray of the printer. Handling the photos then becomes a very delicate operation to avoid smudging the image.

On one occasion, I printed some posters for a charity using the printer manufacturer’s original inks but a third party silk media. The black text took more than a week to reach a state of dryness that allowed the posters to be used!

This leads me to make it clear that globbing is most pronounced in dark areas where the volume of ink placed on the paper is highest. The paper cannot handle the ink, meaning that it sits on the surface of the paper, surface tension draws the ink into globules and there they sit until they eventually dry.

By contrast, the paper in a matched ink and paper pair will receive the ink in the precise position that it was placed, absorb it instantly and protect it from further movement and damage.

Good image - matched ink and mediaGood image – matched ink and media
Pitted surface - mismatched ink and mediaPitted surface – mismatched ink and media

To bring in an example, quite clearly, the paint surface of a car should show as a smooth surface in any photograph. In this example below, however, we see a smooth surface with well-defined edges on the print made with the matched OEM paper but, on the mismatched paper, the surface is horrendously pitted and the edges looking like they have been sculpted by a blind rhinoceros wielding a flame thrower!

Severe ink ‘globbing’ - mismatched ink and mediaSevere ink ‘globbing’ – mismatched ink and media

Zooming in, the loss of image becomes even more pronounced. Indeed, so much detail is lost that, even looking at the photo from a normal viewing distance (around 45cm) the image can easily be seen to be seriously flawed – to the extent that any self-respecting snap-shooter would reject it, let alone a discerning photo enthusiast.

This flaw is present on every one of the 12 photos in the CharisCo Photo test suite, regardless of the subject matter.

Unfortunately, the story doesn’t even end here. Because the ink is sitting on the surface of the paper, and not allowed to dry, when the next print falls on top of it as it is ejected onto the output tray of the printer, it collects a significant smear of ink on its reverse side and there is a danger that the two prints might stick together as the ink eventually dries.

I allowed the set of 12 prints to fall into the output tray with no interference and let them sit there for 10 minutes after the print run had finished. This scanned image shows what the back of each and every photo typically looks like.

Dirty photo back - mismatched ink and mediaDirty photo back – mismatched ink and media

Clearly, dirt on the back of a photo is not a huge problem in itself but – where has that dirt come from? It comes from the front of another photo!! Meaning – the image of that other photo has been compromised by losing ink.

Needless to say, the back of every photo in the set printed on OEM original paper was perfectly clean.

Not every mismatched ink and paper combination will demonstrate such severe flaws. However, by definition, every mismatched pair is incapable of producing an image of an equal quality to the matched pair.

Taking this a little further, when an inkjet owner buys a set of inks or a pack of paper that results in printing with a combination that is not matched, that owner takes a risk. The risk is that the pairing will be so bad that the printed images will be unusable. If this is the case, the owner has wasted the money spent on the ink or paper because it will be necessary to return to a combination that is suitably matched.

But, worse than this, the prints made will need to be reprinted. So, even if the owner bought only a mismatched paper while using original inks, the ink used to print the first set of photos has been wasted and the whole pack of paper is effectively wasted even if it hasn’t been used.

In the end then, it is a question of whether the owner is prepared to take the risk of wasting money for the sake of attempting to save money. The risks and scale of wastage are significant.

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