Do Ebonite and Celluloid Mix?

[BerneseMtDogEatsArco]

Hi All,

 

I'm wondering if I have a pen body made of celluloid and a cap made of ebonite, will there be problems cause by:

 

Unequal change in material properties from heat or through time?

Chemical reactions? They both smell, so there's gotta be some chemical mixes.

 

If there are issues, then would a celluloid and acrylic pen be OK?

 

Thank you all for your expertise and assistance!

 

Michael (Berner)

[grimakis]

Not really. Old Pelikans were Celluloid and HR. You might have some discolouring... Such is evident in in Sheaffer Flattops and Balances, where the barrel is celluloid and the section is rubber. Modern cellulose acetate shouldn't discolour however...

[nyawn]

Plenty of pens in the 20's and 30's had an ebonite section in a celluloid body (Sheaffer flat-tops and Balance pens, for one major example). I'm not aware of any cracking endemic to these models, or discoloration due to the different materials (that doesn't rule out the possibility...I just never heard of it). Discoloration in Sheaffer celluloid is often attributed to the sac rubber, and many examples actually show less discoloration near the section, suggesting the ebonite section is not the cause of the discoloration.

[bgray]

I'm glad to see this thread.

 

I know that this myth has appeared here a couple of times.

 

I think that someone posted pics of some pens that were stored for like 10 years in a pen box and never touched. There were ebonite and celluloid pens in the same box. The celluoid pens "melted" for some reason, and everyone assumed that the ebonite out-gassed, destroying the celluloid. I think that this was what started the myth. I have no idea what caused the celluloid damage, but it wasn't the ebonite.

 

There is no danger in mixing these materials. In addition to the pens mentioned above, there are also depression era Parkers that were celluloid with ebonite sections.

 

No harm in it.

[grimakis]

I'm glad to see this thread.

 

I know that this myth has appeared here a couple of times.

 

I think that someone posted pics of some pens that were stored for like 10 years in a pen box and never touched. There were ebonite and celluloid pens in the same box. The celluoid pens "melted" for some reason, and everyone assumed that the ebonite out-gassed, destroying the celluloid. I think that this was what started the myth. I have no idea what caused the celluloid damage, but it wasn't the ebonite.

 

There is no danger in mixing these materials. In addition to the pens mentioned above, there are also depression era Parkers that were celluloid with ebonite sections.

 

No harm in it.

 

Yes, some Vacumatics had the HR section as well.

 

~George

[Ernst Bitterman]

This is based on things I've picked up lurking around here-- I can't document it, but I believed it when I read it:

 

The sulfur in ebonite causes ambering in celluloid. The long the ebonite had been about, the less sulfur it's going to lose, and the less of an issue it is in proximity with celuloid. A 1940s Vacumatic, for example, is as effected as it will ever be by it's HR parts. While unsightly, it doesn't really affect the stability of the material. I've a brand new Indian HR eyedropper that gets to live on its own, very far from the rest of my pens, but I don't mind a Waterman 52 sharing digs with my Geometric Duofold.

 

Celluloid when not quite generated properly tends to crystalize and fragment. This sucks in the case of the particular item (button collectors also fear this effect), but since it releases vinegary vapours which act somewhat as an enzyme it can actually spread from one pen to another, seemingly a communicable disease, which REALLY sucks. If one had a case of collapsing celluloid pens, it's not the HR that's the blame, but probably one of the pens.

[ZeissIkon]

Celluloid when not quite generated properly tends to crystalize and fragment. This sucks in the case of the particular item (button collectors also fear this effect), but since it releases vinegary vapours which act somewhat as an enzyme it can actually spread from one pen to another, seemingly a communicable disease, which REALLY sucks. If one had a case of collapsing celluloid pens, it's not the HR that's the blame, but probably one of the pens.

 

Vinegar vapors are a sign of "vinegar syndrome" which affects acetate, not celluloid. The equivalent celluloid degradation doesn't have a catchy name, AFAIK, but is the condition responsible for deterioration of old photographic films (only if stored in nearly airtight containers, like, say, film reel cans). The decomposing celluloid releases nitric oxide, which accelerates decomposition of celluloid, a cycle that can, as a worst case, run away and cause spontaneous ignition (film storage warehouses have burnt down as a result of this).

 

So far as I know, there's no effect from sulfur related to this, though an acidic environment (as from sulfur dioxide reacting with moisture) can promote decomposition of both celluloid and acetate.

[rwilsonedn]

If there were a problem with outgassing from ebonite discoloring or damaging celluloid, wouldn't the caps on pretty much all celluloid pens show damage, since they would be sealing in the vapors from an ebonite feed? But in my limited experience, it's the barrel, not the cap, that usually discolors on an old celluloid pen.

ron

[ZeissIkon]

If there were a problem with outgassing from ebonite discoloring or damaging celluloid, wouldn't the caps on pretty much all celluloid pens show damage, since they would be sealing in the vapors from an ebonite feed? But in my limited experience, it's the barrel, not the cap, that usually discolors on an old celluloid pen.

ron

 

The latex of the sac, while of lower percentage sulfur content, has a lot more area to outgas sulfur compounds, and it in close proximity, if not direct contact, with the barrel, while the ebonite feed is well separated from the cap (and has the inner cap to protect the visible cap).

[Vintagepens]

Going back to addressing the original query:

Hard rubber and celluloid are highly compatible materials, short-term and long-term.

 

There is a large amount of misinformation in circulation about both materials, unfortunately.

Please note that one does not have to cast about for examples of vintage pens made using both hard rubber and celluloid -- this was the norm for pen construction from the mid-1920s through the 1940s (which is to say, the norm for pens made of celluloid!). It is very much the exception for a vintage celluloid pen NOT to have a hard rubber section, and many that did have celluloid sections actually had the section lined with hard rubber.

 

I still find it puzzling that some regard hard rubber as a culprit in the discoloration of old celluloid pens. As noted above, it is quite clear that discoloration is primarily caused by the deterioration of ink sacs, and secondarily by the ink itself. Hard rubber components often shield celluloid from these discoloring agents, so it is quite obvious that they are not causing any problems -- quite the opposite.

 

 

[grimakis]

Going back to addressing the original query:

Hard rubber and celluloid are highly compatible materials, short-term and long-term.

 

There is a large amount of misinformation in circulation about both materials, unfortunately.

Please note that one does not have to cast about for examples of vintage pens made using both hard rubber and celluloid -- this was the norm for pen construction from the mid-1920s through the 1940s (which is to say, the norm for pens made of celluloid!). It is very much the exception for a vintage celluloid pen NOT to have a hard rubber section, and many that did have celluloid sections actually had the section lined with hard rubber.

 

I still find it puzzling that some regard hard rubber as a culprit in the discoloration of old celluloid pens. As noted above, it is quite clear that discoloration is primarily caused by the deterioration of ink sacs, and secondarily by the ink itself. Hard rubber components often shield celluloid from these discoloring agents, so it is quite obvious that they are not causing any problems -- quite the opposite.

 

I have seen Jade Sheaffers that had no sac, but discolouration only around the section. This would be an area protected from the out gassing of sacs, no? There is no denying the main culprit is the ink sac, but I wouldn't go as far as to say that rubber sections will have no negative effect on colour and clarity. I think it is possible that with the addition of light, and heat, hard rubber parts will out gas. At least that is my theory.

[pen2paper]

http://www.plastiquarian.com/deterio.htm

celluloid, ebonite, Metal, ink residue-heat, light, airless environment... humidity/lack of..stored with what other materials?

[BerneseMtDogEatsArco]

Thanks for your advice! I, too, had seen the post about the 10 Omas pens that had disintegrated, which was the impetus behind the post.

 

Many regards for clearing this up!