Frit-bonding as a possible joining method for feldspathic earthenware

Johannes H Stephensen
Tværfagligt kandidatprogram

Danish feldspathic earthenware from the post war period and forward has a special chalenge in connection with restoration. It is still considered primarily as a users object, but as this type of earthenware is no longer in production, it becomes increasingly rare as the damaged parts are discarded.

The thesis has three focus areas:
On the background of a historical-technological review of Danish post war feldspathic earthenware, and a historical, cultural and ethical review of restoration methods, a series of experiments is set up. The tests endeavour to identify a glass frit bonding, mixed with organic glue, which will pre-glue broken faience together, and in a subsequent burning at low temperature achieve that the frit will melt and tie the sherds together
The tests introduces at frit especially developed for the electronic industry. With Frit 14019/DG from Ferro Ltd. mixed with Universal glue from Danalim (cellulose nitrate) it is possible to make a suitable strong binding. Test specimens cut from above mentioned faience was glued with the frit glue, was tested for strength and shock heat tests according to the Harkorts method. The frit recipe showed good results but needs continued development.