Bull's Head and Mermaid - The Bernstein Project - Österreichische ...
Bull's Head and Mermaid - The Bernstein Project - Österreichische ...
Bull's Head and Mermaid - The Bernstein Project - Österreichische ...
You also want an ePaper? Increase the reach of your titles
YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.
ine bleaching needed control <strong>and</strong> was not easy to dose.<br />
<strong>The</strong> printers were particularly afraid of the chemically active<br />
residual chlorine, because of the damages caused by aggressive<br />
halogen which could also effect corrosion. In the<br />
first half of the 19 th century there existed a series of further<br />
approaches for the industrial bleaching of papermaker’s<br />
raw materials. Hypochlorite liquids <strong>and</strong> bleaching powder<br />
became accepted for the treatment of raw materials step by<br />
step until the middle of the 19 th century, but they were not<br />
able to solve finally the problem of the shortage of raw materials.<br />
Gottlob Friedrich Keller from Hainichen who became interested<br />
in the raw materials problem of the papermakers<br />
through publications of the years 1839/40 wrote down in<br />
his ‘Poecketbook of Ideas’ in 1841/42: “To produce paper<br />
by wooden fibres, which are manufactured by friction.”<br />
Presumably without knowledge of Schäffer’s studies, he<br />
started his wood grinding experiments in December 1843.<br />
Adding 20 percent rags in the paper Mill of Carl Friedrich<br />
Gottlob Kühn at Alt-Chemnitz 5–6 reams of paper from<br />
mechanically processed wood pulp were produced. Afterwards<br />
calendered in a cotton mill at Hainichen <strong>and</strong> on October<br />
11 th , 1845 printed at the print shop of Carl Gottlob<br />
Rossberg in Frankenberg for the number 41 of the ‘Intelligenz-<br />
und Wochenblattes für Frankenberg mit Sachsenburg<br />
und Umgebung’, published at November 1 st , 1845 as the<br />
first print product worldwide on mechanical wood pulp paper.<br />
Subsequently, Keller signed a contract with Heinrich Voelter<br />
(1817–1887) to the effect of the economic exploitation<br />
of the process. Voelter had to go systematically after applications<br />
for Patens in the German countries <strong>and</strong> abroad,<br />
which due to the multitude of the German countries <strong>and</strong><br />
their own patent laws which caused a lot of costs <strong>and</strong><br />
which were not in a well balanced relation to the attainable<br />
profit, since the duration of the protection often lasted only<br />
for five years. <strong>The</strong> invention did not pay off for Keller <strong>and</strong><br />
so additional two decades passed, during which the machine<br />
manufacturer Heinrich Voelter began first alone later<br />
on together with the engine builder Johann Matthäus Voith<br />
(1803–1874) from Heidenheim to make efforts concerning<br />
technological development <strong>and</strong> commercialisation. Voith<br />
build 21 wood grinders in the period 1852–1860, which<br />
Voelter supplied to buyers at home <strong>and</strong> abroad. <strong>The</strong> world<br />
exhibition of 1867 in Paris alone brought the breakthrough<br />
(Ill. 14). Voelter exhibited there a complete furnished wood<br />
grinding mill inclusively all auxiliary machines <strong>and</strong> samples<br />
of the finished paper. From that time on the raw materials<br />
shortage for the developing paper industry was solved <strong>and</strong><br />
one not depend any more alone on textile remains, which<br />
till then the ragmen could get hold of in towns <strong>and</strong> in the<br />
countryside.<br />
While Keller had cleared the way for making paper of<br />
wood by mechanical means, others tried to use chemical<br />
dissolving methods. <strong>The</strong> English chemists Hugh Burgess<br />
(1825–1892) <strong>and</strong> Charles Watt produced sodium pulp from<br />
cottonwood <strong>and</strong> hemlock wood in 1851. According to this<br />
method at first in America pulp has been produced in industrial<br />
scale since 1863, but without any commercial success.<br />
Already before Mellier in France invented a method to<br />
produce straw pulp in 1854. Benjamin Chew Tilghman<br />
(1821–1903) tested the influence of sulphur dioxide on fats<br />
Ill. 14: Title page of Voelter’s advertising brochure from 1867 on<br />
the world exhibition in Paris. In the cartouche Voelter’s wood<br />
grinder is reproduced.<br />
in 1857 <strong>and</strong> observed on this occasion how it affected <strong>and</strong><br />
softened wood. Tilghman had experimented with that sulphur<br />
method for two years, but in spite investing a lot of<br />
money he was not able to avoid the failures in sealing the<br />
digester <strong>and</strong> resigned at the end. It was not until 1871 the<br />
Swede Carl Daniel Ekman (1845–1904) succeeded to boil a<br />
usable sulphite pulp using magnesium bisulphite. A<br />
Swedish mill produced using this process starting in 1874.<br />
Concurrently with Ekman the German chemist Alex<strong>and</strong>er<br />
Mitscherlich (1836–1918) conducted long test series in order<br />
to find usable digester materials for preparing sulphite<br />
pulp. Only an acid resistant stone coating proved to be a<br />
sustainable solution for the problem which Tilghman<br />
fought with. Alex<strong>and</strong>er Mitscherlich <strong>and</strong> his brother Richard<br />
received a series of domestic <strong>and</strong> international patents<br />
within the years 1874 to 1878, e.g. the first German patent<br />
dated February 5 th , 1875. Alex<strong>and</strong>er Mitscherlich was able<br />
already in the year 1877 to supply by wagonloads the paper<br />
industry with his chemically prepared pulp. <strong>The</strong> sulphite<br />
process needed wood with low resin content <strong>and</strong> was very<br />
well applicable to the digestion of spruce wood. <strong>The</strong> pulp<br />
prepared herefrom had already after the digestion a high<br />
degree of whiteness <strong>and</strong> was well bleachable.<br />
On the other h<strong>and</strong> the sulphate method developed by<br />
Card F. Dahl in Danzig in 1879 was well applicable to all<br />
23