EFNIR: Platinum Chou Kuro

[LizEF]

Extra Fine Nib Ink Review: Platinum Chou Kuro

This is review #280 in my series. Here's the YouTube video:

Post-recording notes: Most reviews focus on the blackness, waterproofness, and cleaning. Precious few actually talk about how it writes or behaves in the pen. So, I'll comment on everything I can think of about this ink.

I pre-cleaned with distilled water and the ultrasonic cleaner, then allowed everything to dry *before* I inked the pen. Given the images others have posted of the ink's reaction with tap vs distilled water, I thought it might give my pen a little better chance if any residue from tap water was cleaned off ahead of time.

When put on thin enough, this is a warm dark grey (see microscope smear). That surprised me - I thought it would be a black hole even in thin applications, but no. When enough is applied, it is blacker than my darkest inks (see video comparisons). In heaviest application, it looks wet - sort of shiny or almost silvery sheen (see video). My other blacks were mostly cooler, and quite a few turn grey in comparison. A few still seemed black, but not as black. Of note is the Pilot Black for Parallel pens - historically, that swatch has seemed solid black to me. Now it seems solid, darkest cool grey.

Also of note are De Atramentis Document Black, Noodler's Heart of Darkness, and Noodler's Black (when applied heavily). These three held up best against Chou Kuro. And Noodler's Black was most similar in color and in how much blacker it is in heavy application.

This ink was gifted to me by an Instagram friend. In the sample vial, it sloshes around easily and stays together. It doesn't cling to or try to stain the walls. There was no sign of settling as some other pigmented inks do. It does form quite a lot of bubbles when you shake it up. Some dried to a solid on the threads, but it did re-wet, so it may not be the end of the world if it dries in a pen, but you'd have a hard time cleaning it out, so I highly recommend against that - use a pen that seals well.

When writing in my journal (generally in cursive and constant writing), I had no flow problems, but the longer the pen was inked, the less the pen liked to start writing - the first strokes were not as solid (you can see this in some images).  Doing logic puzzles (about 48 hours after inking), the pen ran dry. The paper was thick copy paper. I was making dots, Xs, and lines, and writing constantly - it was a simpler puzzle, so no need for pauses and capping. Wiping the back of the nib on the paper and then scribbling some lines brought it back to life, only to happen a second time. After repeating the process, it flowed better. So, it seems like this ink won't take very long pauses without drying on the nib. A wetter nib might not have this problem. The problem did not recur on subsequent days, even when doing more logic puzzles. I did have flow problems near the end of the doodle and flossed the tines to get it flowing well again (that doodle was a demanding task for the ink).

Cleaning was not bad. I put some distilled water in a stainless steel measuring cup and dropped the nib and feed in there with the disc and agitator ball from the cartridge. I rinsed the section and cartridge with a couple syringe-fulls of distilled water, then put everything into an ultrasonic cleaner with a little distilled water and ran it once. I don't think that was needed, it was just easiest. The cartridge seemed stained (sort of a warm brownish grey), but nothing else. The ink seems to come off non-porous surfaces quite easily, though with agitation (e.g. I had to wipe it off my stainless steel sink when I got some on it). It also comes quite easily off skin (more easily than many even non-permanent inks)!

NOTE: Given the claim of blackest black, I went ahead and compared not only swatches, but also the review pages from all my former blacks to see if one can distinguish this from other blacks in writing from a Japanese EF.  There were so many blacks that looked just as black to me that I didn't bother to try to capture comparison photos - any differences are likely too subtle to distinguish. There were also many that looked distinctly greyish.  But IMO, if you're using a Japanese EF nib, this ink may not be different enough to justify the cost.

Note on Shading and Sheen: Though I put "None", technically, it will shade in a dry-enough application, but I'm not sure a normal nib will get it that thin.  The circular/disc dip nib I use for making swatches these days can do it.  As to sheen, mostly, there's nothing, but in heavy application, when held at an angle to the light, you see what looks like sheen, or maybe like the ink is wet. I think it's just light reflecting off thick ink. I've seen this in some writing in my Hobonichi (52gsm Tomoe River paper) and on the swatch card. (See the video for an example from my doodle.)

All in all, if you want the blackest black and don't choke on the price or the distilled water for cleaning, this is your ink!

This is a very cool PDF from Platinum about this ink.

Zoomed in photo (I think the broken lines are because the ink sometimes dries on the nib. Once it gets going, the lines aren't quite as broken.)

Screenshot

Scan of Completed Review

Absorbent Paper Close-up (top is puzzle paper like thick newsprint, bottom is old 20lb copy paper)

Line width ("1" in "10" in dry-time test. Magnification is 100x. The grid is 100x100µm. The scale is 330µm, with eleven divisions of 30µm each. The line width for this ink is roughly 248µm. With 280 inks measured, the average line width is 296µm.) (Holy opacity, Batman! Note the red spots - that usually means sheen.  I used a different line because the usual ones weren't representative (drying on the nib, I think), but it's still thin!)

Microscope image (100x. Looks very much like pretty much all pigmented inks look - granular, pattern that looks like the edges of clouds or the build-up of multiple layers of mineral deposits at a hot spring.)

Water Test Results

Other (Toward the end of this doodle (the curves at the top), the pen was struggling and needed a bit of flossing and rest to refill the feed - not sure we can fault pen or ink - I was putting down a lot of ink in a short time.)

Previous Review: Pilot Mixable Colour Light-green.

Images also available on Instagram: @zilxodarap.

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View a list of my inks, complete with review results in a google sheet.

Need to catch up on The Adventures of Quin and Makhabesh? Find the whole story here.

Hope you enjoy. Comments appreciated!

[yazeh]

Wow, wow, wow 👍

This must he the holy Chou Kuro of ink reviews 🖖

The amount of work which had gone into this review. BRAVO🙀

I don't know where to start. The thinnest line, the video scroll of darkness at the end or the solar eclipse / mineral deposit microscopic image or the mystery at the palace of the fake/ real high wizard?

Amazing review. No wonder you had sleepless nights 🤣

[LizEF]

54 minutes ago, yazeh said:

Wow, wow, wow 👍

This must he the holy Chou Kuro of ink reviews 🖖

The amount of work which had gone into this review. BRAVO🙀

Thank you!

 

54 minutes ago, yazeh said:

I don't know where to start. The thinnest line, the video scroll of darkness at the end or the solar eclipse / mineral deposit microscopic image or the mystery at the palace of the fake/ real high wizard?

 

54 minutes ago, yazeh said:

Amazing review.

Thanks!

 

55 minutes ago, yazeh said:

No wonder you had sleepless nights 🤣

I don't think this ink can be held accountable for that.  Hopefully it provides some additional information on top of all the "really black and hard to clean" reviews out there....

[Sailor Kenshin]

Holy Mud Monster, Quin!  

 

The mystery deepens.  Like, wowsville, duude.  So like who's really the High Wizard?  (Sorry for going all Beatnik there).  

 

To the tune of rattlesnakes and groans!

 

@LizEF, thanks so much for the Tuesday Treat, and for reviewing an ink I surely do not want in my arsenal.  

 

Fascinating and thorough, nevetheless!  I do not have any of the comparison inks this time.  Love your Zentangles, too.

 

And I absolutely love the story.  It was welcome after Eclipse Day, followed by this morning's heavy yard work.

 

[Penguincollector]

    Thanks for demystifying this ink, Liz.  It seems like there’s an almost ritualistic quality to using it, with all of the preparation due to its ability to form precipitates with tap water and other contaminants. I feel about black inks like you do about blues, so while I’m probably not going to buy it for myself, it’s nice to know how it behaves just in case. Your doodle (Zentangles! Thanks for supplying the word I was looking for pre coffee, @Sailor Kenshin!) is gorgeous, really engaging with all of the little details; I stared at it for awhile. I have to go to your website and read the last few chapters of the story, because I am somewhat confused, this happens every couple of reviews so I reread to become au courant.

[LizEF]

10 minutes ago, Sailor Kenshin said:

Holy Mud Monster, Quin!  

 

11 minutes ago, Sailor Kenshin said:

The mystery deepens.  Like, wowsville, duude.  So like who's really the High Wizard?  (Sorry for going all Beatnik there).  

 

11 minutes ago, Sailor Kenshin said:

To the tune of rattlesnakes and groans!

 

11 minutes ago, Sailor Kenshin said:

@LizEF, thanks so much for the Tuesday Treat, and for reviewing an ink I surely do not want in my arsenal.  

You're very welcome!

 

12 minutes ago, Sailor Kenshin said:

Fascinating and thorough, nevetheless!  I do not have any of the comparison inks this time.  Love your Zentangles, too.

Thank you!

 

12 minutes ago, Sailor Kenshin said:

And I absolutely love the story.  It was welcome after Eclipse Day, followed by this morning's heavy yard work.

Thanks!  Yes, it's that season again - away with the snow shovel and out with the mower...

[LizEF]

10 minutes ago, Penguincollector said:

Thanks for demystifying this ink, Liz.

You're very welcome!

 

11 minutes ago, Penguincollector said:

It seems like there’s an almost ritualistic quality to using it, with all of the preparation due to its ability to form precipitates with tap water and other contaminants. I feel about black inks like you do about blues, so while I’m probably not going to buy it for myself, it’s nice to know how it behaves just in case.

Yep, no black inks for me, either.  I suspect my pre-cleaning was overkill, but I didn't want to deal with cleaning issues - those Pilot grip sections can be very hard to clean.

 

12 minutes ago, Penguincollector said:

Your doodle (Zentangles! Thanks for supplying the word I was looking for pre coffee, @Sailor Kenshin!) is gorgeous, really engaging with all of the little details; I stared at it for awhile.

Thanks!  I enjoy doing them when I can.

 

13 minutes ago, Penguincollector said:

I have to go to your website and read the last few chapters of the story, because I am somewhat confused, this happens every couple of reviews so I reread to become au courant.

I'm long past the point of wanting to just tell the story and not be limited by one scene per week - it's too slow and too easy to forget in between...  But, it is what it is (as they say).  And I am getting practice at being concise...  And as you say, one can always catch up / remind oneself via the website.

[InesF]

Despite being black, this ink has some element of surprise in it!

Thank you, @LizEF, for doing such a precise review of an ink that is nothing else than black.    <all told about colour, appearance on paper and suitability for routine use>

As told already elsewhere, I love your doodle!

 

The ink reveals its secrets not at first sight. In the combination of line structure in the magnified images, from the microscopy photo and what you tell in the (comprehensive) notes, I expect this ink to have very high surface tension (maybe above pure water) and some chemical reactivity with paper cellulose. The uneven line width may not come from unsteady flow alone, it looks like if the wet line is contracting under the surface tension during the time the pigment binds to the paper surface. It would not be a line (it would be more like pearls on a string) if the reaction time would be slower than the set time. You know, the water (or other liquids) can't evaporate within 10 seconds, it must be sucked into the paper structure without pulling (and distributing) essential amounts of pigment with it.

So or something alike.

 

My summary: boring colour 🙄, interesting ink , great review 😁!

 

[yazeh]

5 hours ago, InesF said:

My summary: boring colour 🙄, interesting ink , great review 😁!

 

and indepth analysis of the data by@InesF

[LizEF]

5 hours ago, InesF said:

Despite being black, this ink has some element of surprise in it!

 

5 hours ago, InesF said:

Thank you, @LizEF, for doing such a precise review of an ink that is nothing else than black. 

You're very welcome!

 

5 hours ago, InesF said:

As told already elsewhere, I love your doodle!

Thank you!

 

5 hours ago, InesF said:

The ink reveals its secrets not at first sight. In the combination of line structure in the magnified images, from the microscopy photo and what you tell in the (comprehensive) notes, I expect this ink to have very high surface tension (maybe above pure water) and some chemical reactivity with paper cellulose. The uneven line width may not come from unsteady flow alone, it looks like if the wet line is contracting under the surface tension during the time the pigment binds to the paper surface. It would not be a line (it would be more like pearls on a string) if the reaction time would be slower than the set time. You know, the water (or other liquids) can't evaporate within 10 seconds, it must be sucked into the paper structure without pulling (and distributing) essential amounts of pigment with it.

So or something alike.

Love reading these things!  So instructional!

 

5 hours ago, InesF said:

My summary: boring colour 🙄, interesting ink , great review 😁!

  Thank you!

[LizEF]

38 minutes ago, yazeh said:

and indepth analysis of the data by@InesF

[Sailor Kenshin]

On 4/9/2024 at 11:36 AM, Penguincollector said:

    Thanks for demystifying this ink, Liz.  It seems like there’s an almost ritualistic quality to using it, with all of the preparation due to its ability to form precipitates with tap water and other contaminants. I feel about black inks like you do about blues, so while I’m probably not going to buy it for myself, it’s nice to know how it behaves just in case. Your doodle (Zentangles! Thanks for supplying the word I was looking for pre coffee, @Sailor Kenshin!) is gorgeous, really engaging with all of the little details; I stared at it for awhile. I have to go to your website and read the last few chapters of the story, because I am somewhat confused, this happens every couple of reviews so I reread to become au courant.

 

You're welcome, @Penguincollector.  I had no idea this ink generated so much interest!

[arcfide]

Love the review! I continue to go through my black inks trying to find my favorite, and I've yet to do so. I really would enjoy picking up a bottle of this stuff, but for the very warm tone. 

 

It seems to me that the warm toned blacks can come off darker than anything else when applied heavily enough, but if they go on light enough to show off the color tone, I tend to not like them at all. *sigh* 

[LizEF]

25 minutes ago, arcfide said:

Love the review!

Thank you!

 

25 minutes ago, arcfide said:

I continue to go through my black inks trying to find my favorite, and I've yet to do so. I really would enjoy picking up a bottle of this stuff, but for the very warm tone.

Pretty sure the warm tone is only on microscope slides and when it's spread thin.  In normal writing, it's just black.  I don't think any other reviewer has commented on it.

 

26 minutes ago, arcfide said:

It seems to me that the warm toned blacks can come off darker than anything else when applied heavily enough, but if they go on light enough to show off the color tone, I tend to not like them at all. *sigh* 

You'd need a dry, broad-ish nib to spread this stuff thin, I think...

[arcfide]

4 hours ago, LizEF said:

You'd need a dry, broad-ish nib to spread this stuff thin, I think...

 

This is, in fact, always the problem. I use very broad nibs (Pelikan's Broad nib size is my "normal writing size" nib, and I've used Platinum and Sailor Coarse/Zoom nibs for regular writing before), and they always tend to spread the ink out more than other nibs, which tends to make every ink shade or otherwise appear paler than what people get with fine or medium nibs. I can see shading from all of Sailor, Pilot, Platinum, Waterman, Pelikan, Herbin, Iroshizuku, and Diplomat black inks, for instance, in my normal pens, including the very wet writing ones. Platinum's Carbon ink is probably the least likely to shade, but it's also the highest maintenance, and I'm sure I'd get still a little shading in the Italic Broad Pelikan. 

[LizEF]

9 minutes ago, arcfide said:

This is, in fact, always the problem. I use very broad nibs...

Ah, yes, that would be a challenge.  Of course, Pelikan are wet, so I'd think they'd do a good job of giving you a solid line, even if the Japanese nibs don't...

[Lithium466]

So, despite pushing the boundaries of what can be done with suspending particules, the mighty EF can only get dark-warm-dark-grey-that-looks-dark-enough but not the marketed and expected literal liquid void? 
That looks like an excellent ink to me, dark enough, waterproof, excellent lubrication, super skinny thin lines (yes!), no feathering (skinny lines and feathering being Platinum carbon black's nemesis) 😍

Oh it dries on the nib. Ah, you can't have it all. And the price, ouch!

 

Maybe a Platinum Carbon black+ could be a happy medium? The pros of both inks, minus the cons. That sounds like a speech from a 2000's French politician.

 

In any case, thank you @LizEF for that impressive review!

[LizEF]

3 hours ago, Lithium466 said:

So, despite pushing the boundaries of what can be done with suspending particules, the mighty EF can only get dark-warm-dark-grey-that-looks-dark-enough but not the marketed and expected literal liquid void?

From the EF nib itself, the ink is black as anyone could hope.  It's only in the swatch and microscope slide where it didn't.  But yeah, not always liquid void.  (Which is fine by me - I prefer my furry void. )

 

3 hours ago, Lithium466 said:

That looks like an excellent ink to me, dark enough, waterproof, excellent lubrication, super skinny thin lines (yes!), no feathering (skinny lines and feathering being Platinum carbon black's nemesis) 😍

Oh it dries on the nib. Ah, you can't have it all. And the price, ouch!

Yes, very good ink, if it's something you want / need...  I think a hooded nib and wet-flowing pen are probably best for it - or perhaps just a non-arid environment...

 

3 hours ago, Lithium466 said:

Maybe a Platinum Carbon black+ could be a happy medium? The pros of both inks, minus the cons. That sounds like a speech from a 2000's French politician.

  I wonder what would happen if you mixed them.....

 

3 hours ago, Lithium466 said:

In any case, thank you @LizEF for that impressive review!

You're very welcome!  And thank you!

[liapuyat]

I looked up this review because I was gifted a bottle last March. It's already December and I've only gotten around to thinking I want to try it now. So I've identified a sacrificial Jinhao 82 pen with an F nib that's easily disassembled for cleaning. I am hoping the writing experience won't be frustrating - I hope there won't be much skipping once it gets going. Do you suggest a dip in distilled water in case it dries out on the nib? Or should I just wipe the nib on tissue to get it going again? Well, we'll see. Thank you so much for the review. 

[LizEF]

24 minutes ago, liapuyat said:

Do you suggest a dip in distilled water in case it dries out on the nib?

That's the safest option.

 

26 minutes ago, liapuyat said:

Or should I just wipe the nib on tissue to get it going again?

I would worry about it picking up fibers from the tissue.

 

27 minutes ago, liapuyat said:

Thank you so much for the review. 

You're most welcome! Hope the ink works well for you.