İM- A com- PROVEMENTS IN THE MANUFACTURE OF ENAMELLED IRONWARE
Year: 1878

page_text: LETTERS PATENT to William Robert Lake, of the Firm of Haseltine, Lake, &
Co., Patent Agents, Southampton Buildings, London, for the Invention of "İM-
A com-
PROVEMENTS IN THE MANUFACTURE OF ENAMELLED IRONWARE."
munication from abroad by Frederick Gottlieb Niedringhaus and William
Frederick Niedringhaus, both of St. Louis, Missouri, United States of America,
Manufacturers
COMPLETE SPECIFICATION filed by the said William Robert Lake at the
Office of the Commissioners of Patents on the 20th March 1878.
WILLIAM ROBERT LAKE, of the Firm of Haseltine, Lake, & Co., Patent Agents,
Southampton Buildings, London. "IMPROVEMENTS IN THE MANUFACTURE OF
ENAMELLED IRONWARE." A communication from abroad by Frederick Gottlieb
Niedringhaus and William Frederick Niedringhaus, both of St. Louis, Missouri,
United States of America, Manufacturers.
Heretofore in enamelling ironware difficulty has been experienced in making the
enamel when fused entirely cover the metallic base. The enamel would separato
entirely from the base in spots, causing the base to appear in the form of black
specks, and the enamel throughout was not always reliably adhesive to the base.
It has been ascertained by experience that the difficulty referred to is due to the
presence of carbon in the metallic base. If any carbon remains therein the
following result occurs in forming the enamel, namely:-After the paste has been
applied to the ware, and the latter has been placed in the baking oven, just before
the fusing point of the enamel is reached the carbon assumes a gaseous form, and
endeavours to escape from beneath the enamel; it bursts through in places, leaving
the base bare, and forming the spots above described, and weakens the attachment
of the enamel generally.

page_text: This Invention affords the means for overcoming this difficulty by thoroughly
expelling the carbon from the metallic base before the application of the enamelling
paste. The latter is then applied, and the enamel is fused in the ordinary manner.
Not only is the appearance of the enamel greatly improved by its entire freedom
from blemishes, but the adhesion of the enamel to the base is increased.
The preferable manner of expelling the carbon from the metallic base is as
follows, that is to say-The various articles of the ware, after having been properly
shaped, are enclosed with lime in a suitable box or receptacle, so as to exclude thé
air; they are then heated nearly to a white heat, and then allowed to cool slowly.
The carbon leaves the iron during the heating, and combines with the lime.
The carbon, however, can be expelled from the iron when the latter is in the
form of bars, and before it has been rolled into sheet iron.
Having thus fully described the said Invention as communicated to me by my
foreign correspondents, and the manner of performing the same, I wish it understood
that I claim,-
First. The herein-described improved mode of enamelling iron ware, which consists
in expelling the carbon from the metallic base before the formation of the enamel
thereon for the purpose specified.
Second. The improved enamelled sheet iron, in which the enamel is fused upon
a decarbonized metallic base.
In witness whereof, I, the said William Robert Lake, have hereunto set my
hand and seal, this Twentieth day of March, in the year of our Lord One
thousand eight hundred and seventy-eight.