Cellulose nitrate vs. acetate

[MarcShiman]

Giovanni,

 

This raises some good questions. Celanese Corporation bought The Celluloid Company in 1927 and started work on Lumarith, their brand of cellulose Acetate. Apparently a rod showed up of Lumarith in a Sheaffer museum.

 

However, I can't really find any literature on when pen manufacturers actually adopted it. Who was the first pen company? Who used Rhodoid in their pens?

 

Someone forwarded me an article from 1941 stating that if you use a recently made pen, its most likely made from celluloid acetate. That isn't what I expected.

 

Marc

[tryphon]

Most of the info I have came from Mazzucchelli. They were among the first companies in Europe to manufacture celluloid and rhodöid.

[Vintagepens]

Giovanni, was the trade name Rhodöid used at all in the USA?

 

I have researched this issue. What I found is that cellulose acetate should be called by its original name, which was Rhodoïd.

It will avoid confusion if we stick to: celluloid for cellulose nitrate pens and Rhodoïd for cellulose acetate pens.

[Vintagepens]

Esterbrook had gone to cellulose acetate by then, at least in the USA. As we all know, the top-line American penmakers were still using either celluloid or sometimes acrylic in 1941, with acetate widely adopted only after the war. That article could well have had a rather different perpective, though, and may have been focusing on pens for the masses. There are certainly lots of now-horribly-distorted cheapies from the era that were not made from celluloid, and likely did make use of acetate instead.

 

Synthetic camphor smells the same as natural camphor, by the way.

 

Someone forwarded me an article from 1941 stating that if you use a recently made pen, its most likely made from celluloid acetate. That isn't what I expected.

 

Marc

[tryphon]

Giovanni, was the trade name Rhodöid used at all in the USA?

 

 

I believe it was, for instance for aircraft windows and similar. The name clearly comes from Rhone-Poulenc, but it became commonly used for this type of plastic here in Europe (including the UK), just like it had happened before with celluloid. In Italian, it was sometime called rodoide.

[MarcShiman]

One of the problems of trying to come up with a generic name for CA is that there were so many different formulations for it. While Celluloid pretty much had one formula (perhaps with some variation on how it was made), camphor was the plasticizer.

 

They tried camphor as a plasticizer in CA and it wasn't effective. There were over two hundred different agents used as plasticizers used in different formulations of CA.

[Carl Fisher - F3 Pens]

Great discussion and if I might ask the opinion of the material experts.

 

I try to work with vintage materials whenever I can when making pens. However some materials are either incorrectly described by the seller or just flat out unable to be 100% identified accurately.

 

One of my favorites is what I had considered to be celluloid. Typically flat sheets that are spiral wrapped into hollow tubes of varying thickness. It has a distinctive smell that is not the menthol smell or the smell of the cellulose acetate (that one I can identify quickly) and it's one that I really can't describe. Since I don't know exactly what camphor smells like I can't identify it with that or not.

 

Another recent material I've started working with comes in larger patterned blocks that I slice up into pen sized blanks. The most recent material gives off fine hairs when cutting and has a distinctive menthol or sports creme smell to it.

 

Any thoughts would help me accurately identify some of the materials to customers that I work with regularly, Many have been coming out of France and claim anywhere from the 1920's - 1950's

 

Thanks!

[Jamesbeat]

If you want to identify if it is celluloid, try carefully burning a small piece.

Hold a small piece in an old pair of pliers, and ignite it outside over a bucket of water. Drop it in the water if it gets too intense.

Use welding gloves and a face shield.

You'll know instantly if it is real celluloid, because it will burn vigorously.

 

I have been looking into various plastics recently, as I am going to be making a few pens soon.

 

Many sellers fraudulantly refer to any plastic as 'acrylic', but can be anything from PMMA (actual acrylic) to crappy polyester resin.

 

I have found some blanks at Bear Tooth Woods that they refer to as 'acrylic acetate', which is meaningless as far as I can tell.

I presume they are acetate, and that they put the word 'acrylic' in there because of all the dumb people who think acrylic is a generic term for plastic.

 

I won't be using celluloid, because, while it is not as flammable as cellulose nitrate specifically made as a propellant, it is still flammable enough to make easily ignited chips when machined.

I don't want finely-divided cellulose nitrate all over my shop!

Edited February 1, 2016 by Jamesbeat

[Vintagepens]

For a flame test, you don't need a big chunk, just a shaving.

It's much easier to ignite celluloid when it's finely divided, whether as chips or as swarf. When turning celluloid, it's best not to let the swarf build up. It makes a great cement when dissolved in alcohol, MEK, or acetone.

In comparison, solid celluloid takes some effort to ignite.