Interesting phenomenon with Platinum dyestuff Black ink in Water Test

[arcfide]

I was testing some water resistance, and I discovered this interesting behavior in Platinum's dyestuff black ink. I noted that Platinum's box for the stuff says, "Contains special resin component for improved water and light resistance...." Given the classic translation difficulties that I usually see on such boxes, I wasn't sure whether this was just a mislabeled reference to the Platinum Carbon Black ink or something else. When I tested it, however, it definitely behaves differently than other dye-based black inks that I have. I have tested it against the following:

 

• Waterman Black
• Herbin Perle Noire
• Jacques Herbin Noir Abyssal
• Jacques Herbin Noir Inspiration
• Sailor Black
• Lamy Black
• Parker Quink Black
• Pilot Iroshizuku Take-sumi

 

The behavior of all the other inks behaved exactly like you would expect a dye-based ink to behave which isn't explicitly waterproof. The ink tends to lift off and what amount managed to sink into the paper (less for ink resistant papers) will leave some left over residual ink/staining in the paper fibers. Importantly, the "darkness" of the residual mark usually correlates pretty well with the quantity of how much ink made it onto the page in that spot, so the end result tends to be a faded copy of what was there before, usually with some color shift towards a warm or cool tone. 

 

For the sample below, I tested on LIFE L Writing Paper using a cotton swab in a single pass to get a wet and dry application across the single line from a single dip to get a feel for how the ink will behave with wet and dry applications. I swabbed the following inks in order:

 

1. Waterman Black
2. Herbin Perle Noire
3. Platinum Dyestuff Black
4. Jacques Herbin Noir Abyssal
5. Jacques Herbin Noir Inspiration
6. Platinum Blue Black
7. Herbin Bleu Nuit
8. Waterman Mysterious Blue
9. Jacques Herbin Bleu de Minuit

 

I wanted to have a selection of various inks that were both standard and that I knew had certain behaviors. The Jacques Herbin Noir Abyssal and Bleu de Minuit represent high saturation, very wet inks. The Noir Inspiration represents a "super penetrator" with how wet it is. The Platinum Blue Black is iron gall. Waterman's inks represent a known standard, and Herbin's Perle Noire and Bleu Nuit represent the equivalent "standard" in a different brand with different compositions, but without the "boutique" level properties. Perle Noire is generally well respected for its relative water resistance given that it's a very traditional ink. 

 

This time around, I was weird and took the sheet into the shower with me and let the paper get sprayed down for a while. This meant that it was less intense than you would get from a multi-hour soak, but more than your typical few minutes soak. 

 

 

The interesting thing here is how the Platinum Black just kind of has this uniform blackness across the whole line without any of the typical features you would expect, as you see from the black inks just above and below it.

[lapis]

Great! Most surprising (to me) is that their blue-black IG doesn't seem to be as water-resistant as their black!!

[arcfide]

7 hours ago, lapis said:

Great! Most surprising (to me) is that their blue-black IG doesn't seem to be as water-resistant as their black!!

 

In practice, one big difference is that Blue Black tends to "stay" with much less observed run off. It's color stays blue for a remarkably long time, and overall it "feels" more water resistant, even though in the end it washes out to the IG grey/black. The Black is, I think, less immediately permanent IME. It also bleeds off more ink when you first put it under water, which can cause less clarity to the letters if you just get a drop on the page. 

 

Of course, they're two different colors, so they're kind of competing in different spaces, but even so, unless you make them wetter, both Platinum inks are "drier" and have more shading than many other inks of the same color range, and that can have a practical impact on daily writing and water resistance, because some inks can put down so much dye compared to the Platinum that they can stay water resistant for a while out of sheer volume of dye on the page (such as the Noir Inspiration ink above). 

[amberleadavis]

Thank you for this illustration of water fastness.  Only on FPN can you discuss taking paper into the shower.  I admit, I've washed papers with soap and let them dry.