Transparent Celluloid Ambering

[SilverPearlVacumatic]

Hello Everyone,

 

Does anyone know or have any idea what causes transparent celluloid to amber? I previously figured it was a combination of ink stains and sunlight damage, but I noticed even the plastic plungers of some Parker vacumatics are more ambered than others, despite being sheilded from sunlight and protected from ink equally.

[Pickwick]

Unfortunately it comes with aging. I'm unsure whether any restoration can be done. Other members may be able to pass on to you their own experiences.

Edited July 25, 2015 by Pickwick

[SilverPearlVacumatic]

It would be interesting to know if some environments age the plastic more than others or if there are just some bad batches. It is interesting to note that black vacumatics have better transparency.

[pen2paper]

till the experts arrive edit: which they are, so exit stage left...

Basically early plastic plus metal requires reasonable care.

Edited July 26, 2015 by pen2paper

[ac12]

Also outgasing from ink sacs. I've seen a LOT of older pens where the cap is nice, but the body around the ink sac has darkened considerably.

[pen2paper]

p2p, (ever the student), has been corrected (thanks with cheerful smile), so read on below.

Edited July 26, 2015 by pen2paper

[FarmBoy]

ac12 I immediately thought the same thing, but realized we were discussing a Parker Vac. Which, sort of goes past the rubber outgassing issue? Correct? That's why I posted, it seemed pertinent to the no sac involvement issue??? Vacs are not my specialty, is there rubber used with a Vac?

A sac in a vac is the same material as a sac in a not vac.

[SilverPearlVacumatic]

Often the back end of a vacumatic (where the diaphragm is), is the last place to amber completely. Would the ambering patterns lead us to conclude temperature swings affect it greatly (everything on a single pen affected at a constant rate) and contact with rubber is a major variable?