Reason for black gel pen refills leaking in winter

[Wrichik Basu]

I mainly use black gel pens for writing. Every year in winter, I notice an awkward incident - almost every black gel pen refill that I have, start leaking! And it leaks regardless of the position in which I keep the pen - upright, slanting, horizontally on a table or upside down. For example, I unpack a new refill, and put it in the pen. After about 20 minutes, the cap is full of ink leaking out of the refill.

The interesting fact is that, this is not happening with refills of only one company. Till date, I've tried five different companies, and black refills from each of them are leaking in the same manner. It's leaking so much that I have had to throw the full refill most of the time.

However, none of the blue pens are leaking. They are kept under the same physical conditions as the black refills, but they're not leaking at all.

This makes me think that there is some physical phenomena associated with it. I've seen pens leaking at high altitudes. But I'm living in Kolkata, India, which is on the plains, and the altitude is barely 9m from the sea level.

This started mainly from last winter. Nothing like this happened in summer, and it has again started this year. The minimum temperature this year has dropped to 11°C in Kolkata.

The pictures are:

Can anyone account for this? And is there any way by which I can prevent it?

 

[jedishrfu]

http://www.penturners.org/forum/f18/what-causes-ballpoint-leak-ink-122378/

One poster suggested that maybe the refills are broken when you get them from someone storing them outside in the cold.

 

[Wrichik Basu]

http://www.penturners.org/forum/f18/what-causes-ballpoint-leak-ink-122378/

One poster suggested that maybe the refills are broken when you get them from someone storing them outside in the cold.

I've added two pics.

The refills are definitely not broken in my case.

 

[phinds]

I've added two pics.

The refills are definitely not broken in my case.

Of course they are "broken" in at lease some sense. They DO leak after all. The "breakage" could well be in a seal at the point you indicate and this could be cause by expansion due to cold storage as the robot suggested.

 

[Wrichik Basu]

@phinds I'm changing the picture for clarification. The ink is leaking from the tip of the nib and not the joint.