AN IMPROVED MANUFACTURE OF LIGNEOUS COMPOUND AND OF ARTICLES MOULDED THEREFROM IN IMITATION OF WOOD AND OTHER CARVINGS
Year: 1883

page_text: PROVISIONAL SPECIFICATION left by Charles Denton Abel at the Office of
the Commissioners of Patents on the 30th January 1883. Communicated to
me from Abroad by Bruno Harrass of Böhlen near Grossbreitenbach, Thüringia,
Germany.
CHARLES DENTON ABEL of N° 28 Southampton Buildings, Chancery Lane in the
County of Middlesex "AN IMPROVED MANUFACTURE OF LIGNEOUS COMPOUND AND
OF ARTICLES MOULDED THEREFROM IN IMITATION OF WOOD AND OTHER CARVINGS
"
[communicated to me from Abroad by Bruno Harrass of Böhlen near Grossbreitenbach,
Thüringia, Germany.]
The artificial wood compound hereinafter described differs in its preparation from
those heretofore employed in that the mixture and treatment of the materials is
effected at the ordinary temperature (15° to 20° Cent.), the use of a water bath in
which the materials required to be boiled, being obviated. By this means the
compound is much more susceptible to being moulded into the required forms and
is consequently capable of receiving great sharpness of configuration. The following
composition, which consists mainly of sawdust or other small woody fibre, bullocks
blood, and glutinous flour, has given good results. Two to four parts by weight of
ground wood (woody fibre) are mixed with from 4 to 12 parts of sawdust, and this
is then mixed with from 4 to 12 parts of blood, preferably bullocks blood, but the
blood of calves, pigs and other animals may be used, or albumin, animal glue, all
kinds of resin or starch, may be used. To this compound is then added from
one fourth part to two parts of glutinous flour and the whole is thoroughly
incorporated. In certain cases there may be used in place of the glutinous flour,
other substances having similar properties, in the same proportions, such for instance
as potato flour, albumin, fibrine, caseine or dextrine. The thoroughly incorporated
compound is then dried at ordinary temperature or at a moderate heat to
accelerate the process.
Before the employment of the finished mass which is dry and has not been
boiled, it must be slightly moistened. For this purpose the inass, prepared of the
proportions above specified, is mixed with from 1/, to 6 parts by weight of blood,
and afterwards with '/th part to 2 parts of glutinous flour, or a similar proportion

page_text: of its above named equivalents, the whole being again thoroughly mixed. The
addition of a moderate quantity of glycerine or of animal or vegetable fats, or wax
is advisable if the moulded articles are to have a smooth shining surface, but this
addition is not essential.
The finished mass is now pressed in a moist condition in metal moulds, heated to
from 150° to 300° Cent. The heating of the moulds may be effected either by
red hot plates, or directly by fire, or by superheated steam, passed through hollow
spaces in the mould.
In order to produce from the above mass ornaments with great sharpness of
outline, it is of advantage to place on the under surfaces thereof paste board in such
manner that this is intimately combined with the mass during the pressing.
By this means also a smooth back surface is obtained, requiring no subsequent
preparation; also, the paste board absorbs the moisture of the mass, so that this
dries more quickly, and lastly the crust which is obtained by the pressing in
heated moulds adheres to the mass effectually and renders the moulded object
more durable, besides being of improved appearance, and prevents the warping
thereof.
To, obtain these advantages, paste board of a loose or absorbent texture is by
preference employed, prepared of cellulose or other fibre, which is saturated with
an aqueous solution of animal or vegetable gum, or with a solution of water-glass,
or of other similar glutinous materials or mixtures thereof. After the paste board
thus prepared, has been perfectly dried, it may be coated with glue or other
glutinous material on the side which is to be applied to the wood compound so
as to insure its perfect adhesion to the latter; this is however not essentially
necessary, nor is the previous impregnation of the paste board, as this is only to
insure a smooth back surface and a more intimate adhesion to the moulded article.
The sheet of paste board of a size somewhat larger than the base of the
ornament to be moulded is laid upon a suitable base and upon it is placed as much
of the moist cold mass as is requisite for producing the ornament. The heated
mould is then pressed on the said mass until the sharp lower edges of the mould
cut into the paste board foundation. As the edges of the mould come in contact
with the pasteboard, the compound cannot further escape, and is consequently
subject to the greater compression, the more the mould penetrates into the paste
board.
After the moulded object has become dry, under alternate opening and closing of
the press, it is taken out of the mould and the fins which may adhere thereto are
removed by a file, whereupon the article is ready for polishing or varnishing.
The impregnated paste board foundation will, as above described, become
intimately connected to the moulded article, and forms a perfectly smooth clean
back surface, and being cut by the edges of the mould, it will receive the same
sharp outline as the compound, which will also be strengthened thereby.
It will be readily understood that ornaments and other objects prepared from the
above described compound can be coated with veneer during the pressing by placing
thin sheets of veneer coated with glue in the heated mould and pressing the compound
directly against. The moulded objects may also be used without veneer, and the
compound can be colored before moulding by admixing the required coloring matter
with the other ingredients.