135 - Albert UNGERER

UNGERER was a chemist resident in Pforzheim;   he invented a number of chemical processes which were protected by patents in some of the German states. 

On 22 March 1872 UNGERER, in association with his business partner Carl Julius MAUERSBERGER, had obtained a patent in Dresden (Sachsen) for a new method for producing paper pulp. [1] They set up a factory for implementing this process in Buchholz.

UNGERER  also obtained patents for the same invention in the USA [2] and in Great-Britain [3].

In the middle of 1872 he moved to Simmering near Vienna where he helped to set up a factory for putting his invention into practice.  

From his address in Austria he applied on 23 July 1872 for a brevet d’importation for his paper pulp making process in Luxembourg, under the tile of:

Méthode de préparation chimique des pâtes à papier

In the corresponding US patent [2] UNGERER explained:

Although my process can be employed for isolating the cells of plants generally, when­ever such is desirable for different purposes, I consider it particularly useful for the purpose of manufacturing pulp, for the use of papermakers, from wood or from the fibres of plants …

The main features of my process are as fol­lows: I put the wood, after cutting it up in small pieces, (preferably as dye-woods are pre­pared or separated,) into closed vessels, in which it is treated at a gradually-increasing pressure, and at a temperature corresponding to the same, with a caustic-soda lye several times renewed and heated beforehand. After being thus treated said woody matter is also thor­oughly washed in the same vessels. This deprives the wood or vegetable matter of incrustating substances, and the connections between the single cells is severed …

The pressure, the duration of the action, and the concentration of the lye must be regulated according to the particular kind of wood, and the degree of bleaching required. For wood from trees, with deciduous leaves, it is sufficient to use a lye containing two or three per cent, of an hydrous caustic soda, the pressure of which rises at the close to three or four atmospheres, and the action ought to last five or six hours.

The Chambre de commerce appointed a commission composed of Jules LAMORT and François REUTER for examining the invention. LAMORT drafted a short report:

Après avoir pris connaissance des procédés de fabrication et avoir examiné les plans, la commission a pu se convaincre de l'importance de l'invention. Jusqu'à présent l'appareil est resté inconnu, sa description n’ayant figuré dans aucun ouvrage, ce qui a été confirmé par les fabricants de papier du Grand-Duché. 

La commission déclare que rien ne s'oppose à donner suite à la demande du sieur Albert Ungerer. 

The Chambre de commerce reported to the Government on 14 January 1872:

La Chambre de commerce a reçu communication d'un rapport présenté par M.M. Jules Lamort et François Reuter, sur la demande du sieur Albert Ungerer, chimiste à Pforzheim, tendant à lui faire obtenir un brevet d'invention et de perfectionnement de 10 ans pour une nouvelle méthode de préparation chimique de la pâte à papier. 

Ce rapport conclut à l’admission de la demande et l'assemblée, dans sa séance d'hier, a déclaré s’y rallier en proposant toutefois de réduire la durée du brevet à 5 ans.

The patent was granted on 30 January 1873 for a period of 5 years only, as recommended by the Chambre de commerce.

It would appear that UNGERER’s process was not successful at the time; a German magazine reported the following in 1876 [4]:

Das sehr interessante, aber etwas complicirte Verfahren von Ungerer nach dem in einer österreichischen Fabrik Cellulose bereitet werden sollte, entzieht sich leider der Beurtheilung, da die betreffende Fabrik, kaum vollendet, bis auf den Grund niedergebrannt ist.


[1] Neue Apparate und Einrichtungen zur Herstellung von Papierstoff aus Holz auf chemischem Wege

[2] US patent No 143,546 (Process of treating fibrous substances for paper pulp)

[3] GB patent No 257/1872 (Improved process or method and apparatus for preparing plants to render them useful in the manufacture of paper pulp)

[4] Dingler’s Polytechnisches Journal, 1876, Volume 219, section 1,  page 435