Improvements in the Manufacture of Pressed Wood or Wood and Composition Panels, Brackets and the like.
Year: 1898

page_text: Improvements in the Manufacture of Pressed Wood or Wood and
Composition Panels, Brackets and the like.
I, WILLIAM PHILLIPS THOMPSON, Patent Agent of Engraved Wood Limited,
Midghall Street, Liverpool, do hereby declare the nature of this invention to be
as follows:-
This invention has for its object the improvement of the manufacture of pressed
wood ornamentation.
In order to enable a greater relief to be obtained than at present practicable
by this process, I adopt a combination of carving and pressure, carving out the
design very roughly (but with smoothed surface) on the wood either along grain
("longwood") or across grain, or a combination of the two, and then press.
Where it is cross cut wood or ingrain it is preferably veneered before pressing,
the lower portions being veneered and where the veneer cannot be stretched so
as to cover projecting parts a separate piece of veneer is placed on these projecting
parts. In some instances the panel is required to stand alone and to stand con-
siderable cross pressure. In such case if I do not place a metallic backing or
skeleton in the panel, I form the panel with long wood back of sufficient thick-
ness and cement the ingrain pressed pattern on the long wood back before or
after it is pressed. In some instances the long wood back can be cut or hollowed
out so as to receive the in grain or pressed panel in recess. This panel can then
be pressed either before or after insertion in the long wood preferably before
insertion, in which case it is trimmed up afterwards to fit the hollow in the
long wood. In my previous patents in which I have mentioned having an iron
or other metal backing or strengthening for a panel I omitted to mention that
this strengthening can be formed of long wood, that is grain running the length
of the pattern instead of the metal and the strengthening can be placed on or
in the panel before or after pressure. If after pressure the edges of the two
panels placed on each side of the wood and the long wood itself can be cut to a
suitable pattern so that the long wood shall project be recessed or be moulded
differently from the two panels one on each side. This is especially valuable
for brackets and the like. The glue solution which has hitherto been used for
saturating the surfaces to be pressed is liable to imbibe water in damp places.
To avoid this it has been proposed in my previous patents to use tanning, solu-
tions, such as tannin bichromate of potash and the like. I now find that a solu-
tion of glue mixed with formaline very useful for this purpose. In my previous
patents I have also mentioned using a plastic material such as resin and sawdust.
I now propose to use a material consisting of whiting or other neutral finely
pulverised insoluble material mixed up to the consistency of dough with a jelly
composed of glue, resin and linseed oil, the whiting being previously dyed to
the colour of the vencer which I propose to use. This material is spread over

page_text: an ordinary piece of long wood and covered with veneer, great care being taken
that no air bubbles be enclosed within. When it is set or nearly set it is placed
under the press and the cement is displaced thus bringing the veneer up to the
required height. Where this material is required to be exposed to damp a little
formaline or in some cases bichromate is added to the jelly. In some cases the
cement is pressed first and afterwards the veneer pressed on to it.
Other cements can be used for this purpose containing resin, sawdust, india
rubber solution, linseed oil, albumen and soda, solvents or other materials used
for forming plastic cements capable of setting hard.
Dated this 21st day of Sentember 1898.
WM. P. THOMPSON & Co.,
Of 6, Lord Street, Liverpool, Patent Agents for the Applicant.
Improvements in the Manufacture of Pressed Wood or Wood and
Composition Panels, Brackets and the like.
I, WILLIAM PHILLIPS THOMPSON, Patent Agent of Engraved Wood Limited,
Midghall Street, Liverpool, do hereby declare the nature of this invention and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
This invention has for its object the improvement of the manufacture of
pressed wood ornamentation and is an improvement on the process patented in
Patents 4355 of 1893, 2292 of 1896, 11182 of 1896, 12436 of 1896, 23941 of 1896
and 5061 of 1898.
In order to enable a greater relief to be obtained than at present practicable
by this process, I adopt a combination of carving and pressure, carving out the
design very roughly (but with smoothed surface) on the wood either along grain
("langwood") or across grain, or a combination of the two, and then press.
Where the wood is cut across the grain it is preferably veneered, before pressing,
the lower portions being veneered and where the veneer cannot be stretched so
as to cover projecting parts a separate piece of veneer is placed on these project-
ing parts. In some instances the panel is required to stand alone and to stand
considerable cross pressure. In such case if I do not place a metallic backing
or skeleton in the panel as set forth in Patent No. 23941 of 1896 and 5061 of 1898
I form the panel with long wood back of sufficient thickness and cement the
ingrain pressed pattern on the long wood back before or after it is pressed. This
is set forth in Figure 1 a section in which A is veneer, B wood cut across grain
and C a piece of wood long grain cemented thereto the whole forms a blank ready
for pressing. It should be rather larger in area than the die and the margin of
the long wood is preferably gradually chamfered off as shown all round so as to
make the outer edge less compressed than any other part and thus less punished
in pressing and more easily cut when required. The dotted line indicates the
surface after pressing. In some instances the long wood back can be cut or
hollowed out so as to receive the ingrain or pressed panel in recess.
This panel
can then be pressed either before or after insertion in the long wood preferably
before insertion, in which case it is trimmed up afterwards to fit the hollow in
the long wood. Both long grain panel and cross grained setting should be
well seasoned in this case before being assembled. This is set forth in Figures 2
and 3 showing section and plan respectively in which D is a frame hollowed

page_text: out in the centre of long wood E a panel of wood cut across grain and veneered
fitted to the recess. The outer part of D is chamfered off so as to more easily
be cut to fit the panel where it is to be placed.
In my previous patents aforesaid in which I have mentioned having an iron
or other metal backing or strengthening for a panel I omitted to mention that
this strengthening can be formed of long wood, (that is grain running the length
of the pattern) instead of the metal and the strengthening can be placed on or
in the panel before or after pressure. If after pressure the edges of the panel
or panels placed on one or each side of the long wood and the long wood itself
can be cut to a suitable pattern so that the long wood shall project be recessed
or be moulded differently from the side panel or panels. This is especially
valuable for brackets and the like. An illustration of this is shown in Figure 4,
in which G is one cross grain panel veneered, H the central long wood support.
A similar panel to G is generally placed on the other side of H. Where there
in a single ornamented side crossgrain, I prefer to chamfer off the edges of the
long wood back as shown in Figure 1 blank so that less pressure may come on
the edges of the panel. The glue solution which has hitherto been used for
saturating the surfaces to be pressed is liable to imbibe water in damp places.
To avoid this it has been proposed in my previous patents to use tanning solu-
tions, such as tannin, bichromate of potash and the like. I now find that a
solution of glue mixed with formaline very useful for this purpose. In practice
the panel is boiled in the glue solution as set forth in Patent No. 4355 of 1893
or is treated with vacuum or exhaustion with or without boiling, but in any
case the glue or gelatine solution is hot (being nearly insoluble cold.) Then
when the wood is impregnated with glue or gelatine or after the glue or gelatine
solution has cooled to below the boiling point of water I add the formaline
(formic aldehyde or solution of trioxymethylene) either to the solution or to the
impregnated wood in sufficient quantity to make the gelatine insoluble say
5 per cent. of formaline to 100 gelatine. In my previous patents I have also
mentioned using a plastic material such as resin and sawdust. I now propose
to use a material consisting of say about 30 pounds whiting or other neutral
finely pulverised insoluble material mixed up to the consistency of dough with
a jelly composed of 3 pounds of glue, previously steeped in water for 24 hours,
2 pounds of resin and 1 pint of linseed oil, (the whiting or other body powder
being previously dyed to the colour of the veneer which I propose to use.) The
three last are melted together with heat & a little water and then the whiting
mixed up with them. This material is spread in a thin layer over an ordinary
piece of long wood and covered with veneer, or a thin sheet say inch of cross
grain wood (preferably impregnated with glue) and veneer, great care being
taken that no air bubbles be enclosed within. When it is set or nearly set it
is placed under the press and the plastic material is displaced thus bringing the
veneer or cross grain wood and veneer up to the required height. Where this
material is required to be exposed to damp a little formaline or in some cases
bichromate is added to the jelly. Where a very white composition is to be used
the resin and linseed oil are omitted and the whiting or other white neutral
powder, white or light coloured glue or gelatine and formaline are alone used.
In some cases the cement is pressed first and afterwards the veneer pressed on
to it.
Other cements can be used for this purpose containing resin, sawdust, india-
rubber solution, linseed oil, albumen and soda, solvents or other materials used
for forming plastic cements capable of setting hard.
Having now particularly described and ascertained the nature of my said in-
vention and in what manner the same is to be performed, I declare that what
I claim is: -
1. The improvements in the invention set forth in the above recited Letters
Patent which consists in roughly carving and smoothing the wood to the required

page_text: shape and then pressing under the die substantially as described, whereby a
greater relief can be obtained than otherwise by pressure.
2. The device for strengthening end grained panels which consists in using a
backing or centering of long grain wood differently moulded or shaped, or other-
wise from the cross grain substantially as described.
3. The combination of a long grain panel chamfered on the outside and having
an end grain and veneer panel let into a recess in same and glued or cemented
in whereby there is less chance of warping and the edges can be more easily
trimmed to suit the panelling or furniture.
4. The improvement in the process more especially described in Patents 4355
of 1893 and 5061 of 1898, in which a solution of gelatinous matter such as glue
is used to impregnate the wood which consists in the addition of formaline (solu-
tion of formic aldehyde) whereby the gluey matter is rendered hard and insoluble
or non-hygroscopic.
5. The plastic composition for use in the manufacture of panels and other
goods formed under heavy pressure with or without formaline substantially as
described.
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WM. P. THOMPSON & Co.,
Patent Agents, of Liverpool, Manchester, Birmingham, and London.