Have you ever wondered what the scientifically optimal writing utensil is to use in your lab notebook? No? Well, this post contains the answer to a record-keeping question you never thought to ask.
The answer comes from one of my favorite books on managing laboratory records, Writing the Laboratory Notebook by Howard Kanare. It was published in the 1980’s (making the section on electronic record keeping highly entertaining) by the ACS and thoroughly covers the how’s and why’s of keeping a proper notebook.
This book is so thorough, in fact, that it spends 6 pages (p. 11-16) on the proper type of paper and ink to use. Kanare even conducts experiments with 15 different types of pens to determine the most colorfast and solvent-fast inks. I found his experiments so interesting that I thought it worth sharing the highlights with you.
Just say no to pencils
First, I should say that pencils are right out. They’re erasable, they smudge, and they don’t copy well when you’re backing up your notebook. If you want to be sure that data hasn’t been changed or lost to illegibility, it’s better to stick with a pen.
Ink color
The choice of ink color comes down to lightfastness, since modern inks no longer contain the harsh acids that eat through paper over time–a historic problem. Kanare tested ink under both fluorescent light and sunlight and found that red inks fade most easily, blue ink fades some (the amount of fading depends on the pen type), and black inks fade the least.
Pen type
Felt-tip pens have a few things going against them from the start. Their inks are water based, making the ink more likely to bleed and less permanent. On the positive side, these porous-tip pens held up to Kanare’s solvent tests (using water, hexane, HCl, acetone, and methanol) about as well as the ballpoint pens.
The other main option, a ballpoint pen, does pretty well under Kanare’s solvent tests and the pen’s solvent-based ink makes writing more permanent. Kanare’s only warning about these pens is that the ink can coagulate or settle during long-term storage, leading to performance problems in older pens.
Kanare also brings up the option of using archival quality pens, but it’s not clear without testing if it’s worth the added expense over the long term.
And the winner is…
You can’t go wrong with a humble black ballpoint pen when writing in your lab notebook. This ink will stand up the most to fading and spills and provide good permanence, making your records readable for a long time.
