Improvements in the Process for the Treatment of Wood for the Purpose of Hardening and Rendering the same Fire and Water Proof.
Year: 1899

page_text: Date of Application, 19th May, 1899
Complete Specification Left, 19th Feb., 1900-Accepted, 7th Apr.,
1900
Improvements in the Process for the Treatment of Wood for the
Purpose of Hardening and Rendering the same Fire and Water
Proof.
I, SIGMUND WILLNER, of 10, Walbrook, in the City of London, Engineer,
do hereby declare the nature of this invention to be as follows:-
This invention relates to an improved process for hardening wood and also for
treating it so as to render it fire and water proof to enable it to be used in
positions where ordinary wood cannot be so conveniently employed where there
is a danger of fire or liability to injury by damp.
In carrying my invention into effect 1 employ an apparatus consisting of a
heater or other vessel into which I place the wood, carrying the same on racks
or frames shaped suitably for the particular sizes of wood or material that is
to be introduced. I heat the vessel preferably by means of steam or hot air
pipes or coils carried within it, or I may jacket the vessel or chamber by means
of a surrounding or external casing into which the heated medium can enter
so as to maintain a uniform temperature within the interior of the vessel when
the wood is under treatment.
I prefer to heat the wood to a temperature gradually introduced up to that
of the boiling point of water and I maintain this higher temperature until all
the moisture has been expelled from the wood. Having thus expelled the mois-
ture from the fibres of the wood I hermetically close the chamber and by means
of an air pump or exhauster I form a complete vacuum within the chamber
containing the wood, preferably employing a pressure of from 5 to 10 atmospheres
depending upon the nature of the wood which is under treatment.
In connection with my heating chamber I employ a boiler or vessel heated in any
ordinary manner and in which vessel I make a solution from ingredients com-
bined in the proportions of 15 parts of tungstate of soda and 10 parts of white
gelatine, this being mixed with water, the solution not being too dilute, but of
a consistency suitable to enter the finest tissues or fibres of the wood that may
be under treatment. I heat this solution to the boiling point and I convey it or
the vapour from the same through suitable pipes and valve and cock connections
to spray pipes formed or carried within the wood chamber, the spray pipes being
arranged within the chamber in a manner to cause the spray which travels from
the heated solution to thoroughly permeate the whole of the wood which is
within the chamber and to pass through the fibres of the same, the vacuum
maintained within the chamber assisting to draw the fluid or vapour into the
spray tubes, so that it may enter readily into the wood fibres. When the wood
within the chamber has become saturated with the solution I apply pressure
to the liquid within it through the medium of the air pipes which previously

page_text: have been in use for exhausting the air from within and I cause pressure to
be placed upon the liquid within by means of air or hydraulic pumps so as to
compress the liquid within the chamber and to force it into thorough contact
with the whole of the wood fibres and I maintain this pressure for some hours,
varying the extent from 5 to 10 or more atmospheres as may be desirable to
suit the kind of wood under treatment.
Having thus saturated and compressed the solution within the wood fibres I
shut off the communication from the air pressure pumps and break the vacuum
within the chamber and allow the surplus solution contained within it to return
to the boiler or furnace vessel. Having then withdrawn the remaining unused
or superfluous quantity of the solution from the chamber I form a vacuum again
within it and then open_communication through suitable pipes and valves to
a third vessel in which I store formic aldehyde. I allow this formic aldehyde
to be sprayed on to the material within the chamber through the spray pipes
which have been employed before for spraying the original solution as before
described, applying pressure gradually to the spray pipes so as to slowly per-
'meate the whole of the fibres of the wood but at a speed and pressure which
will not force out the first solution which has been introduced to the fibres. I
keep this pressure up upon the wood for some hours and then having exhausted
the chamber allow the wood to slowly dry.
I find it preferable to employ tungstate of soda in my original solution
although it is possible to obtain less efficient conditions by using ammonia and
soluble glass or mica.
I do not limit the application of my invention to any particular form of
apparatus or chamber for carrying the wood which is to be treated, nor to any
special manner of heating or introducing the solutions to the material which is
to be carried or operated upon within the chamber, but I modify the form of
vessel together with the connections to the vessels for containing my hardening
and my fire and water proofing solution to suit the extent of the treatment which
is necessary and the particular size and form of timber, logs, or slabs which
are to be operated upon. I prefer, however, to arrange the connections with
the solution chambers so that the one set of spraying or permeating pipes may
be employed alternately for admitting the hardening and the fire-proofing and
water-proofing solution to within the chamber.
D
·
100
e
1000
Improvements in the Process for the Treatment of Wood for the
Purpose of Hardening and Rendering the same Fire and Water
Proof.
I, SIGMUND WILLNER, of 10, Walbrook, in the City of London, Engineer,
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 relates to an improved process for hardening wood and also for
treating it so as to render it fire and water proof to enable it to be used in

page_text: positions where ordinary wood cannot be so conveniently employed where there
is danger of fire or liability to injury by damp.
In carrying my invention into effect I employ an apparatus consisting of a
heater or other vessel into which I place the wood, carrying the same on racks
or frames shaped suitably for the particular sizes of wood or material that is
to be introduced. I heat the vessel preferably by means of steam or hot air
pipes or coils carried within it, or I may jacket the vessel or chamber by means
of a surrounding or external casing into which the heated medium can enter
so as to maintain a uniform temperature within the interior of the vessel when
the wood is under treatment.
I prefer to heat the wood to a temperature gradually introduced up to that
of the boiling point of water and I maintain this higher temperature until all
the moisture has been expelled from the wood. Having thus expelled the mois-
ture from the fibres of the wood I hermetically close the chamber and by means
of an air pump or exhauster I form a complete vacuum within the chamber
containing the wood preferably employing an exhaustion equivalent to from
5 to 10 atmospheres depending upon the nature of the wood which is under
treatment.
In connection with my heating chamber I employ a boiler or vessel heated in any
ordinary manner and in which vessel I make a solution from ingredients com-
bined in the proportions of 15 parts of tungstate of soda and 10 parts of white
gelatine, this being mixed with water, the solution not being too dilute, but of
a consistency suitable to enter the finest tissues or fibres of the wood that may
be under treatment. I heat this solution to the boiling point and I convey it, or
the vapour from the same, through suitable pipes and valve and cock connections
to spray pipes formed or carried within the wood chamber, the spray pipes being
arranged within the chamber in a manner to cause the spray which travels from
the heated solution to thoroughly permeate the whole of the wood which is
within the chamber and to pass through the fibres of the same, the vacuum
maintained within the chamber assisting to draw the fluid or vapour into the
spray tubes, so that it may enter readily into the wood fibres. When the wood
within the chamber has become saturated with the solution I apply pressure
to the liquid within it through the medium of the air pipes which previously
have been in use for exhausting the air from within, and I cause pressure to
be placed upon the liquid within by means of air or hydraulic pumps so as to
compress the liquid within the chamber and to force it into thorough contact
with the whole of the wood fibres and I maintain this pressure for some hours,
varying the extent from 5 to 10 or more atmospheres as may be desirable to
suit the kind of wood under treatment.
Having thus saturated and compressed the solution within the chamber to the
wood fibres I shut off the communication from the air pumps and break the vacuum
within the chamber and allow the surplus solution contained within it to return
to the boiler or furnace vessel. Having then withdrawn the remaining unused
or superfluous quantity of the solution from the chamber I form a vacuum again
within it and then open communication through suitable pipes and valves to
a third vessel in which I store formic aldehyde. I allow this formic aldehyde
to be sprayed on to the material within the chamber through the spray pipes
which have been employed before for spraying the original solution as before
described, applying pressure gradually to the spray pipes so as to slowly per-
meate the whole of the fibres of the wood, but at a speed and pressure which
will not force out the first solution which has been introduced to the fibres. I
keep this pressure up upon the wood for some hours and then having exhausted
the chamber allow the wood to slowly dry.
I find it preferable to employ tungstate of soda in my original solution
although it is possible to obtain less efficient conditions by using ammonia and
soluble glass or mica.
I do not limit the application of my invention to any particular form of

page_text: .
apparatus or chamber for carrying the wood which is to be treated, nor to any
special manner of heating or introducing the solutions to the material which is
to be carried or operated upon within the chamber, but I modify the form of
vessel together with the connections to the vessels for containing my hardening
and my fire and water proofing solution to suit the extent of the treatment which
is necessary and the particular size and form of timber, logs or slabs which
are to be operated upon. I prefer, however, to arrange the connections with
the solution chambers so that the one set of spraying or permeating pipes may
be employed alternately for admitting the hardening and the fire-proofing and
water proofing solution to within the chamber.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I wish it to be
understood that I am aware that processes have been in use for the treatment of
wood in the manner set forth in the Specifications of Patents Nos. 4355 of 1893,
5061 of 1898 and 20115 of 1898 and I make no claim to anything therein
described and claimed but I declare that what I claim is:-
1.) In a process for the treatment of wood for the purpose of hardening and
rendering it fire and water proof the use of a chamber or vessel into which the
wood can be introduced and to which external heat can be applied, this vessel
being subsequently exhausted of air or placed under a vacuum for the purpose
of enabling a solution composed of 15 parts of tungstate of soda and 10 parts
of white gelatine diluted with water to be sprayed, preferably under pressure,
into the fibres of the wood while in a heated or dried condition substantially as
herein before described.
2.) In a process for the treatment of wood in the manner described in the
First Claim, subjecting the wood while within the vacuum chamber to a spray
of formic aldehyde delivered under pressure to the chamber, substantially as
and for the purpose herein before described.
3.) In a process for the treatment of wood the use of a solution containing
ammonia and soluble glass or mica instead of tungstate of soda as a spraying
solution substantially as and for the purpose herein before described.
Dated this 10th dov of W 1000
MARKS & CLERK,
18, Southampton Buildings, London, W.C.,
13, Temple Street, Birmingham, and 25, Cross Street, Manchester,
Agents.