Ink and pH Levels

Acid & Alkaline Levels

What about the acidity of ink? This seems to be a point of ongoing talk on various discussion sites. Is it really important? On one hand I am told it is not that much of an issue. The compatibility of inks and dyes used in the particular inks is more of an issue.

In 1996 Gregory Clark had an article published in Pen World giving the pH levels of a wide variety of inks. A low pH reading indicates the relative level of acid to a high pH reading that indicates the level of alkaline. Some brands/colours are listed with two different readings. That is because Gregory included both the pH levels found through his testing and those reported by the pen manufactures.

Readings that have been previously reported for the pH levels of inks include:

  • 1.7 for OMAS Blue-Black, OMAS Royal Blue, Visconti, Lapis Blue;
  • 2.2 for Montblanc Blue-Black, Montblanc Bordeaux, Pelikan Blue-Black, Visconti Turquoise;
  • 2.6 for Caron d'Ache Imagine in Blue Sky
  • 2.7 for Pelikan 4001 Blue, Visconti Permanent Blue-Black, Pelikan 4001 Turquoise, Quink Washable Blue, Waterman Purple;
  • 2.8 for Caran d'Ache Escape in Caribbean Sea
  • 3.0 for Montblanc Emerald Green, Quink Permanent Black, Waterman Blue-Black, Waterman Blue;
  • 4.0 for Sheaffer Brown, Emerald Green, Peacock Blue;
  • 5.5 for Caran d'Ache Dream in Blue Night
  • 5.6 for Caran d'Ache Protect in Storm
  • 6.1 for Caron d'Ache Travel in Grand Canyon
  • 6.3 for Parker Penman Emerald;
  • 6.5 for OMAS Sepia;
  • 6.6 for Parker Penman Ebony;
  • 6.8 for Herbin Green, OMAS Vespucci Red, Parker Penman Mocha, Parker Penman Sapphire;
  • 7.0 for Waterman Havana
  • 7.2 for OMAS Permanent Black;
  • 7.5 for Parker Penman Ruby; Pelikan Brilliant Green;
  • 7.8 for Visconti Black
  • 7.9 for Rotring black, Waterman red, Caran d'Ache Explain in Carbon
  • 8.2 for Pelikan brilliant red, turquoise, violet
  • 9.0 for Sheaffer jet black

Noodler's Ink has also promoted their ink, and as a basic foundation of their product, as being a pH neutral ink.

The Noodler's Site includes an extensive write-up with photos about pH levels and the effect of inks with corrosive levels on metal.

Noodler's advances that rather than the danger of the dye content of ink it is the pH level that pen users should pay greater attention to in considering their purchase of inks. The dye used to colour inks is important in setting the intensity in colour and how it will fade or not fade.

The Noodler's article suggests that inks with a pH level of between 1.5 and 4 tend to be corrosive.

Confused? Well as a reference point, water has a pH of 7. When buying inks consider a number of factors. In terms of pH levels do not become paranoid. For example, Gregory Clark notes in one of his reviews of ink is that a range of 5.4 to 8.1 was reasonable in his view for pen inks. Noodler's ink notes their inks are "pH neutral" having a range of 6.2 to 7.9.

I'm not a scientist, but my understanding is that the pH level measures the acidity or alkalinity. Where the pH level is less than 7, the solution is acidic, where the pH level is greater than 7 the solution is basic or alkaline. The ranking of 7 is made as that is what is considered a neutral - as that is the pH of pure water at 25 °C.

What does all that really mean? Most modern inks are safe to use in pens. Pens with piston or vacuum fillers would be subject to staining of some inks. This is less of an issue for pens with converters but ink does seep from the nib, and it won't take long for some of the semitransparent pen caps to "show" the staining of ink.

Use your inks and enjoy the colour range. If you are leaving your pen unused for period of time, simply expel the ink and rinse the pen with water.