Topic: Mosser paperweights and the details of transfer printing

[Wuff]

Recently the following - not identified - paperweight was offered on ebay (pictures reproduced with the seller's permission):
(click on images)
It looks to me like the picture paperweights made by Thomas R. Mosser, the founder of Mosser Glass, from the mid 70's to the early 90's: slightly irregular "frosted" base, double frit layer, white glass with the image - and an "M" as identification (arrow). I informed the seller - and a correspondence arose from this. Main point: there doesn't seem to be an "M" but just two "metall bubbles".
This is where you experts come in. I assume the image was created by some sort of transfer printing - correct? What would be the exact procedure, and what would be the dye? Could the dye contain some metal oxide - which came off to form the bubbles - and nothing (or only very little) left to form the "M" as intended?
Or are there other suggestions for a maker of this paperweight?

[David E]

I imagine it is an enamel transfer, which was placed onto the white ground? One of these things that really need examining close-up, Wolf.

[Wuff]

Thank you, David! In an article on Glass Decoration by Guy Massé I find the following

Inorganic inks
Enamels High Temperature
- Frit-ink (enamel) direct decoration: applied ceramic labeling (ACL)
Frit inks comprise of ground glass or ceramic plus organic or inorganic pigments. They are very durable. When properly fired, they are as long-lasting as the glass or ceramic substrate on which they are fired. Some of the drawbacks to decoration with frit inks are considerable energy consumption, slow throughput times, and difficulties in matching colours, amongst others. Frit inks can be based in oil, hot-melt wax, or UV-curable carriers.
- Frit-ink (enamel) transfer applications («chromos»)
In this process, frit inks are printed onto water-slide or heat-release transfer paper and then transferred to the substrate and subsequently fired. Where the contour of the substrate prohibits direct decorating, this process is used. To transfer multicolour prints intact, a final cover coat needs to be applied on the image. The cover coat is usually solvent based, even though the actual inks can be oil based, wax based or UV-carrier based.

The article is mainly about decorating glass on the outside (like drinking glasses) - would the same also apply as an intermediate step for paperweights - and is it what you meant?
What would a lay person have to look for to help decide this question? The weight has been sold in the meantime - but possibly we can get the winning bidder involved.

[David E]

The article is mainly about decorating glass on the outside (like drinking glasses) - would the same also apply as an intermediate step for paperweights - and is it what you meant?
What would a lay person have to look for to help decide this question? The weight has been sold in the meantime - but possibly we can get the winning bidder involved.

Yes, I suppose the same principle applies - the transfer was fixed to the ground and the paperweight was then completed. Difficult to know how to tell it is a transfer when it is encased, but a slight raising of the edges might be evident if viewed carefully.

Frank or Ivo might be able to expand on this a little further.

[Frank]

Just guessing but you could not print it on as an intermediate stage as the glass would need to cool first and then be reheated to finish. More likely it was printed onto the white material, could be plaster or glass and this introduced into the weight making as with any sulphide. Look at the various sequences of paperweight making shown in Reflections on Scotland's glass and note how the weights are made from top to bottom, in general... with some pre-stages.

[Derek]

Hi all

I recently acquired a paperweight with the "M" signature at the base of a picture. It has the same double frit base as Wuffs although my slightly uneven base is polished. See attachment

My research led me to Variety Glass of Ohio and Tom Mosser. According to  Melvins " American Glass paperweights and their makers" the plaques - presumably ceramic - were hand painted by a Ray Bichard of Cambridge before the glass maker encased the plaque. Ray also made plaques for the Degenharts - these have a "D" signature.

However this leaves me with a problem - hand painted?? looking closely at mine it clearly is NOT hand painted - the surface under close inspection resembles a picture in a newspaper made up of dots.

I am inclined to think that these are Mosser weights and that the description in the book is at fault - maybe Bichard hand painted master pictures that were then transferred to the plaques using some sort of process from the printing industry.

Incidently Mosser glass is still runnning  - www.mosserglass.com

Best regards

Derek

[Frank]

They could printed in black and white and then hand coloured, this would be virtually undetectable embedded in glass.

[Wuff]

Incidently Mosser glass is still running  - www.mosserglass.com

Yes - I know they are still in business: I got the information about the maker and the time frame from them - but they were rather reluctant to provide any further information .

Just guessing but you could not print it on as an intermediate stage as the glass would need to cool first and then be reheated to finish.

It would obviously not be printed on the molten glass - but whenever the printing/painting took place on whatever material, it would still be an intermediate step, i.e. one single step of the entire procedure between getting all the material ready and the finished product .

But ... the above comments just bring me to two questions even more basic:

What is the white material?
So far I have always assumed it would be glass - but ceramic ("sulphide material") might be an alternative. What about Murano weights with images on a white ground, or Chinese Whites? Glass or ceramic?

Hand painted or printed?
Recently Nadine offered a Murano weight on ebay (300201474836 - look quickly as long as the images are still online) which looked hand painted to me, and was also described as such. But with more complicated images - like this Whitefriars flower bouquet - I always assumed the images were printed, and for anything after 1960 I would certainly assume colour printed, not b/w and hand coloured. BTW - in the description of this weight it actually states "made by transfer printing onto a cooled white disk of glass".

So now this really gets interesting - thank you to all contributing to this therad!

[Frank]

Transfer printing is the process of transferring the image to the item. The preparation of the transfer itself can be by any process including hand painting - depending on how many you want to produce: Lithography (various) for large volumes, Silk-Screen for short runs, Lino-cut, hand etc.

[alpha]

One of the speakers at Paperwegiht Fest 2008 (May 14-17, 2008 in Wheaton Village) will be speaking on this topic. The fellow's name is Tony Glander, and If you google his name you can find books and CD's that he has on the process.