Improved Method of and Apparatus for Softening and otherwise Treating Wood for the Manufacture therefrom of Textile Fibres, Wood Pulp, Wood Stoppers for Bottles and the like, and for other purposes.
Year: 1891

page_text: Date of Application, 4th July, 1891
Complete Specification Left, 22nd Mar., 1892-Accepted, 21st May. 1892
PROVISIONAL SPECIFICATION.
Improved Method of and Apparatus for Softening and otherwise
Treating Wood for the Manufacture therefrom of Textile Fibres,
Wood Pulp, Wood Stoppers for Bottles and the like, and for
other purposes.
I, ALEXANDER MITSCHERLICH, Professor of Chemistry and Doctor of
Philosophy, residing at Friburg, Grand Duchy of Baden, German Empire, do
hereby declare the nature of this invention to be as follows:-
Wood or woody parts of plants consist of cellulose fibres which are held together
in their longitudinal and transverse direction by substances comprised under the
term incrusting substances;" hitherto it has been possible only to remove the
incrusting matter by boiling the material with chemical substances and to decom-
pose by this means the wood into fine fibres. But it was not known how to loosen
the adhesion of the wood by mechanical means so that it may be disintegrated into
fibres capable of being spun, nor was it known that the wood can be rendered so
brittle, that it may easily be ground and pulverized.
My invention consists in processes and apparatus for effecting such mechanical
disintegration, as I will proceed to describe.
In the course of the mechanical disintegration of the wood, the latter arrives at
a preliminary stage of the transformation which may be termed the softening
operation. This preliminary stage and the working of the softened wood and of
the refuse of the whole process afford valuable by-products.
The wood to be disintegrated is first prepared in a suitable manner.
Wood stocks are sawn into comparatively large pieces and these are divided
parallel with the fibre into sheets of small thickness (small boards) for which
purpose it is advantageous to use wood which is as free from knots as possible, and
freed from the branches grown in, by the well known way of boring out the same.
Woody parts having naturally a smaller cross-section, such as branches, are
subjected to the hereinafter described process either in an unsplit condition, or
according to the thickness, in a more or less split condition.
For carrying out the process it is advantageous (but not necessary) to impregnate
the thin wood sheets with a liquid.
The thin wood sheets are fed (as shown in Figure 1 of the accompanying
drawings) to a tool which has for its purpose to exert frequently repeated and
rapidly successive pressures (in particular by means of rolling) on the wood to be
worked and to bend the latter between two supports. Owing to the frequently
repeated pressures exerted on the same place and along the whole surface of the
wood, the lateral adhesion of the fibres is eventually loosened and the fibres are
isolated from each other. The tool employed for this purpose is preferably
constructed in such a manner, that the part touching the wood is furnished with a
broad surface which is not too thick and is laterally rounded off and which acts
perpendicularly to the fibre in a transverse direction over the wood (see
Figure 1).
The intensity of the pressure to be exerted on the wood, which is dependent on
the nature and the cross section of the latter, is suitably calculated in such a
manner, that the work-piece is bent or cranked beyond its limit of clasticity, close
to its limit of fracture, but always still within the latter (which in German is
designated by the word "Knicken ").
The effect of this sufficiently often repeated pressure consists in loosening and
separating by the numerous bendings or crackings the lateral adhesion of the

page_text: several longitudinal fibres from each other in such a manner, that the wood is
converted first into a soft pliant mass which can casily be divided in its transverse
direction but is torn with difficulty in its longitudinal direction, and is then
transformed into a partially soft and fibrous mass, or finally into a perfectly fibrous
mass.
It is advisable to continue the treatment by means of the rollers only to such an
extent that the fibres can be separated with the fingers but that the adhesion of the
small boards is still well preserved. From these boards the fibrous masses are
then drawn off by means of machines in thinner or thicker bundles and the fibres
so obtained are spun either directly or after having been worked by means of cards,
with or without the addition of other fibres.
When faults have been made in these operations, i.e. when the wood at certain
places has been bent too far so as to become broken, or when the wood has not the
prescribed thickness with respect to the tool as will hereinafter be more fully
explained, and so on, the separation of the fibres will not have taken place in
these parts and the wood remains for the most part in the form of flat small
particles.
These small wood particles may easily be removed if necessary during the further
working by means of cards. These wood particles as well as other refuse of wood
may be hardened by impregnation and then pulverised.
The distance of the supports from each other between which the work piece is
treated, depends on the properties and on the thickness of the wood to be
worked.
When the small boards are too thick with respect to the distance of the
supports, say; usually more than 10 m.m.; also when the supports are large, it is
not possible to obtain a fine disintegration throughout the whole mass and a
separation in layers will take place rendering the further effectual disintegration
of the wood difficult. When the wood is too thin, even for small distances of the
supports, say less than 02 m.m. thick, the disintegration will not take place.
because in this case the wood, owing to its elasticity, bends without changing its
structure.
The carrying out of this process shall now be more fully explained by a definite
example.
The wood to be disintegrated, fir wood, for instance, freed from its knots or
branches, is radially split into small boards of 2 or 3 m.m. thickness. 250 m.m.
length and 50 m.m. width, it is then placed into a dilute aqueous solution of
sulphurous acid preferably 0'25% and 01% of lime, and it remains therein at
least during 8 days at ordinary temperature, and is then worked by means of
fluted rollers. The sulphurous acid produces, in addition to a lighter colour of the
wood, a softening of the incrusting matter without causing any other perceptible
chemical action, and in consequence thereof a slight disintegration of the wood is
produced.
The machinery hereinafter described and shown in Figures 2, 3 and 4 may very
advantageously be employed.
The machinery consists of a framing A A A capable of receiving about from
10 to 30 or even more sets of rollers C C having a diameter of about 35 m.m. and
supported in stationary bearings B B. These rollers are provided with ribs D D
arranged parallel to the axis of the rollers and well rounded off at their bottom
and top ends, the thickness of the ribs as well as the height being 2 m.m. and they
are 3 m.m. apart from each other. The ribs may also have interruptions and they
may also be provided with recesses or the like extending in a curve round the
rollers, this however does not afford any essential advantage. These rollers are
actuated by bevil gear E E secured to the main shaft F which is rotated by a
driving wheel G and pulley gearing.
Above these first rollers are quite similar rollers M M, which are supported by
bearings H H moveable in sliding blocks capable of being raised and which may

page_text: be pressed at will with elastic pressure to a greater or less extent against the
lower rollers by means of the inserted pieces of caoutchouc K K and the screw
spindles L L.
The small wood boards introduced between the suitably adjusted rollers are
repeatedly bent or cracked at numerous places, or, to speak more exactly, they are
bent or cracked a little beyond the limit of elasticity, but always within the limit
of fracture, and they are worked upon by repeated passages through the rollers
with bendings or crackings in a direction essentially transverse to that of the fibre.
At first, so long as the wood is still brittle, the bending is made quite feeble in
order to prevent as much as possible the longitudinal fibre from being broken, and
the wood from being disintegrated into parallel layers; for this purpose the
pressure exerted on the upper rollers is rendered as exactly as possible of such
intensity that a fracture of the wood cannot take place, this depending upon the
thickness, quality and width of the wood to be worked.
The bendings must be as great as possible. without causing cracks in the wood.
The elastic material inserted between the screws and the upper roller bearing,
such as the piece of caoutchouc above mentioned, offers in addition the advantage
that, when the difference in thickness and quality of the small boards is but small,
a uniform conversion is obtained.
The height and distance of the ribs should not be chosen at will, in particular at
the commencement of working. The farther the ribs are distant from each other,
the thicker remain the fibre bundles, but the thicker may be the woody parts
employed in the above stated limits. The nearer the ribs are together the more
the fine disintegration is favoured, until a limit is reached in which the ribs of the
rollers are no longer capable of effecting the bending, and consequently also the
conversion, throughout the whole woody mass.
Under the given circumstances, at a rapid rate of working, it is difficult to avoid
entirely fractures of the small boards. To prevent such fractures the hereinafter
described application of the machines has given satisfactory results.
At the commencement of the rolling. small boards are placed together two by
two and are then worked in the following manner:
On the small boards split in the above described manner it can for the most part
be observed, that on one side the darker parts of the annular rings project while on
the other side they are recessed. When the latter are subjected to the pressure of
the ribs they receive cracks, whilst this is far less easily the case with the former.
For this reason the small boards are placed together in such a manner, that the
sides having the darker parts of the annular rings projecting come in contact with
the ribs, while the other sides are turned inside. These superposed small boards
are subjected at a proportionally strong pressure to the rolling operation until they
have been somewhat softened; then only are they separated from each other and
rolled again in such a way, that they are passed consecutively two by two through
the slowly revolving rollers in leaving between them an intermediate space
which is as small as possible and so that two small boards do not finish
simultaneously.
For the above mentioned thickness and width of the small boards a pressure of
130 kilos. when the boards are superposed, and a pressure of 90 kilos. when they are
single, has been found advantageous.
For uniformly thin small boards, easy to be disintegrated, a passage through
8 sets of rollers when the boards are superposed, and a passage through 16 sets of
rollers, when the boards are single has been found sufficient, but usually a greater
number of passages is more advantageous. Any impregnation during this operation
is superfluous. The numerous repetitions of the cracking effect the gradual
separation of the fibres from each other over the whole small board; this is shown
first by the softening and afterwards by the disintegration of the small board.
The rolling process is continued until the fibres can be separated from each other
with the fingers throughout the whole small board. By continuing the rolling

page_text: operation the single fibres may be still more uncovered, but for the further working
this is not necessary.
For the further immediate working by means of cards, the slightly moistened rolled
small boards are impregnated with oil and subjected to the action of flexible cards
made of thin wire, so that the single though somewhat short fibres may be nearly
completely separated from each other. The moistening with oil or with other
substances of similar action has proved beneficial, as by these means it is possible to
obtain from the wood longer and thinner fibres.
In this condition of the wood the work done by the cards is however relatively
small, and the latter often tear at the same time the naturally weak fibres which
only receive strength by the spinning, i.e. twisting process. But for some operations
for instance when fibres are to be obtained from a partly fibrous and partly soft
woody mass, it is difficult to replace the cards on account of the good removal of
the fibres.
Such a woody mass is produced when small boards of coniferous trees are rolled
during a somewhat long time under a feeble pressure, in which case the darker parts
of the annular rings are converted into a fibrous mass, while the clearer parts remain
soft. But for combining the totality of the disintegrated wood, it is advantageous to
employ first, prior to the working by means of cards, an intermediate operation, or
to omit the former entirely.
To carry out this intermediate operation narrow bodies having sharp or blunt
edges provided with longitudinal roughness are pushed with slight pressure over
the softened or disintegrated wood in the direction of the fibre in such a way that
for the most part fresh parts of the tool enter into contact with the wood.
This is necessary because the tool works only when the edge entering the contact
is free from fibres. To this tool adhere usually fibrous particles which in continuing
their movement pull off from the wood the fibres which are in connection with them:
under certain circumstances the latter are separated by the said tools from the wood
also by the shaving process. According to the pressure, the quality of the tool and
the advanced disintegration of the wood, a separation of coarser or finer fibres will
take place.
The above mentioned operation may be carried out with various kinds of
apparatus, which, after their action has been determined by me, can be modified in
the most different way.
In first place the machine shewn in Figures 5 and 6 may advantageously be
employed.
A vertical shaft a carries a certain number of arms b composed of two parts
connected with each other by means of a hinge joint d turning upwards. On the ends
of these arms are provided sliding carriages c the two extremities of which are
rounded off. To these carriages are secured knives e arranged at a distance of
about 20 m.m. from each other. This distance is so determined, that the long fibres
adhering to the knives only seldom come under the following knife.
The knives are held in the same way as in planes, by wedges and can easily be
adjusted so as to project more or less beyond the lower surface of the sliding
carriages. The latter which, owing to the joints, are moveable upwards, and may
be lifted off separately from their support, rest by their own weight, (which may be
increased by means of metal plates placed upon them,) on a round plate h moveable
round the shaft a. This plate is put in motion by means of a pulley i fastened
thereto and is carried by the projection . The parts of the plate entering into
contact with the sliding carriages, are provided with cards which are inclined in
the direction of the movement of the plate.
This machine is employed in the following manner;
The small wood boards m worked by the rollers are placed separately and
consecutively over the whole plate, upon the cards, in such a way, that the knives
passing over them act in the direction of the disintegration. The plate h is then
put in motion, as indicated above, whereupon each single knife pulls off fibres

page_text: from the surface of the small board. Owing to the circular movement of the
carriage fresh parts of the knives enter generally into contact with the small boards
and take off fibres from the different parts of the same.
As soon as the knives arrive at the parts where the cards are not provided with
small boards, the fibres are always removed by the cards from the knives and the
latter are thus rendered fit for further pulling off fibres. The small boards them-
selves are held fast by the cards underneath them in such a manner that they yield
elastically downwards and sideways, when too strong a pressure would produce
injury.
From the cards on the plate the fibres are removed by other cards as soon as the
whole quantity of fibres cannot be taken up by them. On the degree of projection
of the knife blades from the carriage faces and on the more or less strong pressure
exerted by the latter depends the degree of fineness of the fibre, but also the less or
greater quantity of the same. A good impregnation of the wood with water alone
or first with water and then with oil has been found very advantageous.
The thin small boards operated upon last by this machinery are badly worked by
the latter and for this purpose the following machine is more advantageously
employed. But the process of separating the fibres alone may be carried out by
each of these two machines.
In the same housing A as above described and shown in Figures 2, 3, 4, the
bottom of which has large openings for letting fall through the product obtained,
about 40 sets of rollers are arranged, one set of which having sharp ribs is made to
alternate with a set of rollers having the ribs rounded off. The rollers having the
ribs rounded off lead the small boards slowly (about 4 decimetres a minute) through
the machine in exerting the same pressure on the small boards as the above described
apparatus.
The sets of rollers having sharp ribs revolve at the entrance of the small boards,
in the same direction as the travel of these: at the place of disintegration, in the
reverse direction, and in that case four times as quick as the former: they are
advantageously actuated by a particular shaft. F by means of toothed wheels. The
upper rollers receive a proportionately low pressure but act as uniformly as possible.
with a pressure of about 3 kilogrammes on the width of 100 m.m. of the small
boards. But the rollers of these sets, owing to the size of their bearings always
remain at such a distance from each other, that the sharp parts can never touch
each other. From time to time brushes are passed underneath and above the sets
of rollers over the edges in order to remove the fibres which are there deposited and
interfere with the action of the edges.
The small boards first enter these machines as follows:-
While the sets of rollers having sharp ribs revolve in the same direction as the
others, the worked small boards are brought in the following manner under the first
set of rollers.
On each board exists a direction in which the fibre can easily be separated; this
direction is readily found by scratching slightly with the finger nail. (I call this
direction the disintegrating direction.) On the other side of the small board the
disintegrating direction is in the inverse sense. Four small boards are superposed,
two by two, and so introduced into the first set of rollers, the disintegrating direction
of the small board being turned against the direction of the movement.
As soon as the small boards have entered nearly to the extent of the half of their
length, two other pairs having the same disintegrating direction, are pushed as far
as possible between the former small boards; as soon as this second pair of boards
is nearly half between the rollers, a third pair is introduced in the same manner;
this arrangement is continued without any interruption. As soon as there are
small boards between all the rollers, the sharpened rollers revolve as said above, in
the inverse direction.
The disintegration takes place now relatively rapidly, as the fibre masses fall
through the openings of the bottom.
The number of the rollers or the pressure exerted by them is so determined

page_text: that the small boards coming out of the machine are disintegrated to such an
extent that, at the places where the sharp ribs have worked, they are quite as
thin as shavings. Should this not be the case they are passed again in the same
order through the machine. According to the pressure exerted on the upper
rollers, finer fibres are drawn off in smaller quantity and coarser one in larger
quantity. These thin places of the small boards, after they have passed once
through the machine are introduced inversely always anew into the latter, so that
the thicker parts of the small boards are now exposed in the disintegrating
direction to the action of the sharp rollers, and by the time they leave the
machine arc also converted nearly entirely into a fibrous mass. Instead of a
whole range of rollers, only three may be employed, the middle of which moving
the small board to and fro while the two end rollers pull off the fibres.
The better the disintegration of the small boards has been effected, the finer are
the fibres produced by the above described machinery. It is immaterial whether
the preparatory disintegration has taken place in a purely mechanical or chemical
or in a combined chemical and mechanical way. By means of these machines
longer fibres can be produced even from raw wood,, which fibres however cannot be
compared with those obtained from prepared wood.
Any kind of wood or any ligneous part of plants treated in the same manner
with the fluted rollers and the machinery furnishes fibres fit for use. Any refuse
of wood of sufficient thickness and having longer fibres such as boughs, branches,
outside planks and the like may be used.
The final fineness and strength of the fibre is dependent on the raw material as
well as on the working.
As regards Germany, pine-, fir-, and red pine-wood are particularly suitable for
this manufacture.
The above described method is capable of numerous variations as will be shown
in the following examples.
In lieu of the bendings by means of the said rollers the loosening of the adhesion
of the fibres may also be obtained by a repeated, gradually increased pressure of
long duration on plates furnished with ribs above a furrowed base, where the recess
of one plate corresponds to a rib of the other.
When in the first described machine, in lieu of two fluted rollers, only one fluted
and one smooth roller are employed, the ribs produce in very thin small boards
(shavings) a partial pressure without any remarkable bending and in consequence
disintegration of the wood. If however not very thin small boards but thicker
wood pieces are employed, so that, owing to the pressure of the ribs and the
clasticity of the wood which is below, bendings are produced, a softening and
final disintegration will take place on the surface, where the fluted rollers are
acting.
Each single rib penetrates at the contact place into the wood, but the wood
particles adjacent to these ribs and not exposed to the pressure of the ribs, remain
essentially in their original condition.
For this reason bendings are produced on the surface by the pressure of the ribs,
but owing to the elasticity of the wood, which is below, these bendings disappear
nearly entirely again, after the pressure has ceased.
The clastic effect. which is produced here by the thicker layer of the wood may
of course be obtained also by a peculiar elastic base plate.
The effects which are produced, will take place on the surface in the same
manner as also in small boards or wood picces in which the bendings do not take
place through the whole thickness of the same, when instead of one fluted roller,
two fluted rollers are used.
Only as far as the ribs of the rollers effect a stronger bending, a disintegration
will take place, and it is immaterial whether in the case of two fluted rollers the
ribs of one roller are opposite to the ribs or to the grooves of the other roller.
provided that there is a sufficient quantity of wood between the two rollers for
allowing the bendings owing to the elasticity of the wood. As with these pressures

page_text: only smaller bendings of the wood are produced, the softening and disintegrating
process will go on much slower, than when the ribs act as above described upon the
intermediate spaces.
In thicker wood pieces the fluted rollers press upon the deeper layers only in
such a manner, that they compress the wood a little, whilst owing to the elasticity
of the wood, the ribs do not produce any effect, and in consequence cannot produce
any softening and disintegration.
When, in lieu of the fluted rollers, fluted plates are used, essentially the same
results are produced; one plate may in this case also be replaced by clastic wood
or any other elastic body. The so called soft woods are particularly suitable for
this working of the surface, while hard wood offers. on account of the smaller
amount of elasticity, greater difficulties.
The softened and still more the disintegrated wood does no longer adhere
firmly together sidewise by the action of the increasing substances as does
the original wood, but it will have received everywhere cracks and fine interstices.
These interstices cause the wood when moistened with liquids to take up the
latter by capillary attraction in an exceedingly rapid and abundant manner, which
properly is not shown by the ordinary wood not having these interstices.
When the softened woody parts have been impregnated with waterproof liquids.
such as tar, the treated wood. owing to its great absorbing capacity, receives a
proportionately thick layer, capable of resisting the influence of the weather and
affording protection to the wood which is below.
.
The wood softened on its surface may be used in cylindrical shape in place of
cork for closing bottles and the like.
The obtained fibrous mass shows in comparison with the hitherto known fibre
used in the textile industry quite peculiar properties which can be recognised in
part already with the naked eye. Whilst in the finer textile fibres an insulation
as complete as possible of the cell is desired and obtained, a separation to such an
extent is not advantageous in the above described process for manufacturing textile
fibres, because the wood cells in the insulated condition are too short for being
spun. These wood fibres consist therefore of bundles of cells and have, owing to
the separation of single or more cells from the bundles, a strange appearance
showing the form of ramifications. By means of the microscope the wood cells
separately or in bundles are always distinctly recognisable and they can be
distinguished at once from the cells of wood cellulose as the former appear as full
tubes and the latter as empty collapsed ones.
The soft masses obtained by the first operation by means of the fluted rollers or
the soft parts of the wood remaining therefrom or formed in other mechanical or
chemical ways are very advantageously impregnated with a liquid transforming
the hitherto soft masses into brittle hard bodies, which is suitably obtained for
instance by a saturated solution of salts (sodium sulphate, mineral-salt and the
like).
The wood is converted by these means from the tough mass difficult to be
transformed into a pulverulent condition. into a brittle body easily pulverised, and
it is capable now of being rubbed, stamped, ground or crushed with a proportionately
small amount of power into a fine powder. The good absorption of the impregnating
liquid is favored by the numerous produced cracks and by the fact. that by the
latter the numerous cavities of the wood have become accessible for the absorption
of the liquid.
i
The salts are removed by means of lixiviating apparatus in using reversed
currents, and they are recovered in a solution fit for being used again. The wood
powder which is impregnated with water is used after the water has been partially
or entirely removed. in a wet or dry state, in place of mechanically prepared wood
pulp in the manufacture of paper and so on.
In the same manner as above described the whole waste resulting from the modes
of working wood, is treated, such as not-disintegrated wood shavings, saw dust and
the like. But it is here to be taken into consideration, that the not-softened woody

page_text: mass does not absorb a proportionately large quantity of impregnating liquid and
that for this reason it is not reduced as casily as the softened mass.
is suitable to repeat the impregnation several times.
Datad this 4th dor of I.... 1001
In this case it
ABEL & IMRAY,
Agents for the Applicant.
COMPLETE SPECIFICATION.
Improved Method of and Apparatus for Softening and otherwise
Treating Wood for the Manufacture therefrom of Textile Fibres,
Wood Pulp, Wood Stoppers for Bottles and the like, and for
other purposes.
I. ALEXANDER MITSCHERLICH, Professor of Chemistry and Doctor of
Philosophy, residing at Friburg. Grand Duchy of Baden, German Empire, 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:
Wood or woody parts of plants consist of cellulose fibres which are held together
in their longitudinal and transverse direction by substances comprised under the
term incrusting substances:" hitherto it has been possible only to remove the
incrusting matter by boiling the material with chemical substances and to decompose
by this means the wood into fine fibres. But it was not known how to loosen the
adhesion of the wood by mechanical means so that it may be disintegrated into
fibres capable of being spun, nor was it known that the wood can be rendered so
brittle, that it may easily be ground and pulverised.
My invention consists in processes and apparatus for effecting such mechanical
disintegration, as I will proceed to describe.
In the course of the mechanical disintegration of the wood, the latter arrives at
a preliminary stage of the transformation which may be termed the softening
operation. This preliminary stage. and the working of the softened wood and of
the refuse of the whole process afford valuable by-products.
The wood to be disintegrated is first prepared in a suitable manner.
Wood stocks are sawn into comparatively large pieces and these are divided
parallel with the fibre into sheets of small thickness (small boards) for which pur-
pose it is advantageous to use wood which is as free from knots as possible, and
freed from the branches grown in, by the well known way of boring out the same.
Woody parts having naturally a smaller cross section, such as branches, are sub-
jected to the hereinafter described process either in an unsplit condition, or according
to the thickness, in a more or less split condition.
For carrying out the process it is advantageous (but not necessary) to
impregnate the thin wood sheets with a liquid.
The thin wood sheets are fed (as shewn in Fig. 1 of the drawings accompanying
my Provisional Specification) to a tool which has for its purpose to exert
frequently repeated and rapidly successive pressures (in particular by means of
rolling) on the wood to be worked and. to bend the latter between two supports.
Owing to the frequently repeated pressure exerted on the same place and along the
whole surface of the wood, the lateral adhesion of the fibres is eventually loosened
and the fibres arc isolated from cach other. The tool employed for this purpose is
preferably constructed in such a manner, that the part touching the wood is furnished
with a broad surface which is not too thick and laterally rounded off and which acts
perpendicularly to the fibre in a transverse direction over the wood (see Fig. 1).
The intensity of the pressure to be exerted on the wood, which is dependent on
the nature and the cross section of the latter, is suitably calculated in such a manner.
that the work-piece is bent or cracked beyond its limit of elasticity, close to its limit
of fracture, but always still within the latter (which in German is designated by
the word "Knicken ").

page_text: The effect of this sufficiently often repeated pressure consists in loosening and
separating by the numerous bendings or crackings the lateral adhesion of the several
longitudinal fibres from each other in such a manner that the wood is converted first
into a soft pliant mass which can easily be divided in its transverse direction but is
torn with difficulty in its longitudinal direction, and is then transformed into a
partially soft and fibrous mass or finally into a perfectly fibrous mass.
It is advisable to continue the treatment by means of the rollers only to such an
extent that the fibres can be separated with the fingers but that the adhesion of the
small boards is still well preserved. From these boards the fibrous masses are then
drawn off by means of machines in thinner or thicker bundles and the fibres so
obtained are spun either directly or after having been worked by means of cards,
with or without the addition of other fibres.
When faults have been made in these operations, i.c. when the wood at certain
places has been bent too far so as to become broken, or when the wood has not the
prescribed thickness with respect to the tool as will hereinafter be more fully
explained, and so on, the separation of the fibres will not have taken place in
these parts and the wood remains for the most part in the form of flat small
particles.
These small wood particles may easily be removed if necessary during the
further working by means of cards. These wood particles as well as other refuse
of wood may be hardened by impregnation and then pulverised.
The distance of the supports from each other between which the work piece is
treated, depends on the properties and on the thickness of the wood to be worked.
When the small boards are too thick with respect to the distance of the supports,
say, usually more than 10"; also when the supports are large it is not possible to
obtain a fine disintegration throughout the whole mass and a separation in layers
will take place rendering the further effectual disintegration of the wood difficult.
When the wood is too thin, even for small distances of the supports, say less
than 0'2 thick, the disintegration will not take place, because in this case the
wood, owing to its elasticity. bends without changing its structure.
The carrying out of this process shall now be more fully explained by a definite
example.
The wood to be disintegrated, fir wood, for instance, freed from its knots or
branches is radially split into small boards of 2 or 3m thickness. 250m length
and 50" width, it is then placed into a dilute aqueous solution of sulphurous acid
preferably 0'25% and 01% of lime, and it remains therein at least during 8 days at
ordinary temperature, and is then worked by means of fluted rollers The
sulphurous acid produces, in addition to a lighter colour of the wood, a softening
of the incrusting matter without causing any other perceptible chemical action,
and in consequence thereof a slight disintegration of the wood is produced.
The machinery hereinafter described and shewn in Figures 2, 3 and 4 may very
advantageously be. employed.
The machinery consists of a framing A. A. A. capable of receiving about from 10
to 30 or even more sets of rollers C C having a diameter of about 35m and sup-
ported in stationary bearings B B. These rollers are provided with ribs D D
arranged parallel to the axis of the rollers and well rounded off at their bottom and
top ends, the thickness of the ribs as well as the height being 2" and they are 3"/m
apart from each other. The ribs may also have interruptions and they may also be
provided with recesses or the like extending in a curve round the rollers, this how-
ever does not afford any essential advantage. These rollers are actuated by bevil
gear E E secured to the main shaft F which is rotated by a driving wheel G and
pulley gearing.
Above these first rollers are quite similar rollers M M, which are supported by
bearings HH moveable in sliding blocks capable of being raised and which may
be pressed at will with elastic pressure to a greater or less extent against the
lower rollers by means of the inserted pieces of caoutchouc K K and the screw
spindles L L.

page_text: The small wood boards introduced between the suitably adjusted rollers are
repeatedly bent or cracked at numerous places or to speak more exactly, they
are bent or cracked a little beyond the limit of elasticity, but always within the
limit of fracture and they are worked upon by repeated passages through the rollers
with bendings or crackings in a direction essentially transverse to that of the fibre.
At first, so long as the wood is still brittle, the bending is made quite feeble in order.
to prevent as much as possible the longitudinal fibre from being broken and the wood
from being disintegrated into parallel layers; for this purpose the pressure exerted
on the upper rollers is rendered as exactly as possible of such intensity that a
fracture of the wood cannot take place, this depending upon the thickness, quality
and width of the wood to be worked.
The bendings must be as great as possible without causing cracks in the wood.
The elastic material inserted between the screws and the upper roller bearing,
such as the piece of caoutchouc above mentioned, offers the advantage that when the
difference in thickness and quality of the small boards is but small a uniform
conversion is obtained.
The height and distance of the ribs should not be chosen at will, in particular at
the commencement of working. The farther the ribs are distant from each other,
the thicker remain the fibre bundles, but the thicker may be the woody parts
employed in the above stated limits. The nearer the ribs are together the more the
fine disintegration is favoured, until a limit is reached in which the ribs of the
rollers are no longer capable of effecting the bending, and consequently also
the conversion throughout the whole woody mass.
Under the given circumstances, at rapid rate of working, it is difficult to avoid
entirely fractures of the small boards. To prevent such fractures, the hereinafter
described application of the machines has given satisfactory results.
At the commencement of the rolling, small boards are placed together two by two
and are then worked. in the following manner.
On the small boards split in the above described manner it can for the most part
be observed, that on one side the darker parts of the annual rings project while on
the other side they are recessed. When the latter are subjected to the pressure
of the ribs they receive cracks, whilst this is far less easily the case with the
former. For this reason the small boards are placed together in such a manner
that the sides having the darker parts of the annual rings projecting come in
contact with the ribs, while the other sides are turned inside.
These superposed small boards are subjected at a proportionally strong pressure
to the rolling operation until they have been somewhat softened then only are they
separated from each other and rolled again in such a way that they are passed con-
secutively two by two through the slowly revolving rollers in leaving between them
an intermediate space which is as small as possible and so that two small boards do
not finish simultaneously.
For the above mentioned thickness and width of the small boards a pressure of
130 kilos. when the boards are superposed, and a pressure of 90 kilos. when they are
single has been found advantageous.
For uniformly thin small boards, easy to be disintegrated, a passage through 8 sets
of rollers when the boards are superposed, and a passage through 16 sets of rollers,
when the boards are single has been found sufficient, but usually a greater number
of passages is more advantageous. Any impregnation during this operation is
superfluous. The numerous repetitions of the cracking effect the gradual separation
of the fibres from each other over the whole small board; this is shown first by the
softening and afterwards by the disintegration of the small board.
The rolling process is continued until the fibres can be separated from each other
with the fingers throughout the whole small board. By continuing the rolling
operation the single fibres may be still more uncovered, but for the further working
this is not necessary.
For the further immediate working by means of cards the slightly moistened
rolled small boards are impregnated with oil and subjected to the action of flexible

page_text: cards similar to those of carding machines made of thin wire, so that the single.
though somewhat short fibres may be nearly completely separated from each other.
The moistening with oil or with other substances of similar action has proved
beneficial as by these means it is possible to obtain from the wood longer and
thinner fibres.
In this condition of the wood the work done by the cards is however relatively
small and the latter often tear at the same time the naturally weak fibres which,
only receive strength by the spinning, i.e. twisting process. But for some operations
for instance when fibres are to be obtained from a partly fibrous and partly soft
woody mass, it is difficult to replace the cards on account of the good removal of
the fibres.
Such a woody mass is produced when small boards of coniferous trees are rolled
during a somewhat long time under a feeble pressure, in which case the darker
parts of the annual rings are converted into a fibrous mass, while the clearer parts
remain soft. But for combing the totality of the disintegrated wood, it is
advantageous to employ first, prior to the working by means of cards, an inter-
mediate operation, or to omit the former entirely.
To carry out this intermediate operation narrow bodies having sharp or blunt
edges provided with longitudinal roughnesses are pushed with slight pressure over
the softened or disintegrated wood in the direction of the fibre in such a way that
for the most part fresh parts of the tool enter into contact with the wood.
This is necessary because the tool works only when the edge entering into
contact is free from fibres. To this tool adhere usually fibrous particles which in
continuing their movement pull off from the wood the fibres which are in connection
with them, under certain circumstances the latter are separated by the said tools
from the wood also by the shaving process. According to the pressure, the quality
of the tool and the advanced disintegration of the wood a separation of coarser or.
finer fibres will take place.
The above mentioned operation may be carried out with various kinds of
apparatus, which, after their action has been determined by me, can be modified in.
the most different ways.
In first place the machine shown in Figures 5 and 6 may advantageously be
employed.
A vertical shaft a carries a certain number of arms b composed of two parts
connected with each other by means of a hinge-joint d turning upwards. On the
ends of these arms are provided sliding carriages c the two extremities g of which
are rounded off.
To these carriages are secured knives e arranged at a certain distance of
about 20 from each other. This distance is so determined, that the long fibres
adhering to the knives only seldom come under the following knife.
The knives are held in the same way as in planes, by wedges and can easily be
adjusted so as to project more or less beyond the lower surface of the sliding
carriages. The latter, which owing to the joints are moveable upwards, and may
be lifted off separately from their support, rest by their own weight, which may be
increased by means of metal plates placed upon them on a round plate moveable
round the shaft a. This plate is put in motion by means of a-pulley i fastened
thereto and is carried by the projection . The parts of the plate entering into
contact with the sliding carriages, are provided with cards which are inclined in
the direction of the movement of the plate.
This machine is employed in the following manner. The small wood boards m
worked by the rollers are placed separately and consecutively over the whole plate
upon the cards, in such a way that the knives passing over them act in the
direction of the disintegration. The plate is then put in motion, as indicated
above, whereupon each single knife pulls off fibres from the surface of the small
board: Owing to the circular movement of the carriage fresh parts of the knives
enter generally into contact with the small boards and take off fibres from the
different parts of the same.

page_text: As soon as the knives arrive at the parts where the cards are not provided with
small boards, the fibres are always removed by the cards from the knives and the
latter are thus rendered fit for further pulling off fibres. The small boards
themselves are held fast by the cards underneath them in such a manner that
they yield elastically downwards and sideways, when too strong a pressure would
produce injury.
From the cards on the plate the fibres are removed by other cards as soon as the
whole quantity of fibres cannot be taken up by them. On the degree of projection
of the knife blades from the carriage faces and on the more or less strong pressure
exerted by the latter depends the degree of fineness of the fibre, but also the less
or greater quantity of the same. A good impregnation of the wood with water
alone or first with water and then with oil has been found very advantageous.
The thin small boards operated upon last by this machinery are badly worked
by the latter and for this purpose the following machine is more advantageously
employed. But the process of separating the fibres alone may be carried out by
cach of these two machines.
In the same housing A as above described and shown in Figures 2, 3, 4, the
bottom of which has large openings for letting fall through the product obtained,
about 40 sets of rollers are arranged, one set of which having sharp ribs is made
to alternate with a set of rollers having the ribs rounded off. The rollers having
the ribs rounded off lead the small boards slowly (about 4 decimetres a minute)
through the machine in exerting the same pressure on the small boards as the
above described apparatus.
The sets of rollers having sharp ribs revolve at the entrance of the small boards
in the same direction as the travel of these; at the place of disintegration, in the
reverse direction, and in that case four times as quick as the former; they are
advantageously actuated by a particular shaft F by means of toothed wheels. The
upper rollers receive a proportionately low pressure but act as uniformly as
possible, with a pressure of about 3 kilogrammes on the width of 100% of the
small boards. But the rollers of these sets, owing to the size of their bearings
always remain at such a distance from each other, that the sharp parts can never
touch each other. From time to time brushes are passed underneath and above
the sets of rollers over the edges in order to remove the fibres which are there
deposited and interfere with the action of the edges.
The small boards first enter these machines as follows. While the sets of rollers
having sharp ribs revolve in the same direction as the others, the worked small
boards are brought in the following manner under the first set of rollers.
On cach board exists a direction in which the fibre can easily be separated; this
direction is readily found by scratching slightly with the finger nail (I call this
direction the disintegrating direction). On the other side of the small board the
disintegrating direction is in the inverse sense. Four small boards are superposed,
two by two, and so introduced into the first set of rollers, the disintegrating
direction of the small board being turned against the direction of the movement.
As soon as the small boards have entered nearly to the extent of the half of
their length, two other pairs having the same disintegrating direction, are pushed
as far as possible between the former small boards; as soon as this second pair of
boards is nearly half between the rollers, a third pair is introduced in the same
manner this arrangement is continued without any interruption. As soon as there
are small boards between all the rollers, the sharpened rollers revolve as said above,
in the inverse direction.
The disintegration takes place now relatively rapidly, as the fibre masses fall
through the openings of the bottom.
The number of the rollers or the pressure exerted by them is so determined that
the small boards coming out of the machine are disintegrated to such an extent
that, at the places where the sharp ribs have worked, they are quite as thin as
shavings. Should this not be the case they are passed again in the same order
through the machine.

page_text: According to the pressure exerted on the upper rollers, finer fibres are drawn
off in smaller quantity and coarser ones in larger quantity. These thin places of
the small boards, after they have passed once through the machine are introduced
inversely always anew into the latter, so that the thicker parts of the small boards
are now exposed in the disintegrating direction to the action of the sharp rollers,
and by the time they leave the machine are also converted nearly entirely into a
fibrous mass. Instead of a whole range of rollers, only three may be employed,
the middle of which moving the small board to and fro while the two end rollers
pull off the fibres.
The better the disintegration of the small boards has been effected, the finer are
the fibres produced by the above described machinery. It is immaterial whether
the preparatory disintegration has taken place in a purely mechanical or chemical
or in a combined chemical and mechanical way. By means of these machines
longer fibres can be produced even from raw wood, which fibres however cannot be
compared with those obtained from prepared wood.
Any kind of wood or any ligneous parts of plants treated in the same manner
with, the fluted rollers and the machinery furnishes fibres fit for use. Any refuse
of wood of sufficient thickness and having longer fibres such as boughs, branches,
outside planks and the like may be used.
The final fineness and strength of the fibre is dependent on the raw material as
well as on the working.
As regards Germany, pine, fir- and red pine-wood are particularly suitable for
this manufacture.
The above described method is capable of numerous variations as will be shown
in the following examples.
In lieu of the bendings by means of the said rollers the loosening of the adhesion
of the fibres may also be obtained by a repeated, gradually increased pressure of
long duration on plates furnished with ribs above a furrowed base, where the recess
of one plate corresponds to a rib of the other.
When in the first described machine, in lieu of two fluted rollers, only one
fluted and one smooth roller are employed, the ribs produce in very thin small
boards (shavings) a partial pressure without any remarkable bending and in
consequence disintegration of the wood. If however not very thin small boards
but thicker wood pieces are employed, so that owing to the pressure of the ribs
and the elasticity of the wood which is below, bendings are produced, a softening
and final disintegration will take place on the surface, where the fluted rollers
arc acting.
Each single rib penetrates at the contact place into the wood, but the wood
particles adjacent to these ribs and not exposed to the pressure of the ribs, remain
essentially in their original condition.
For this reason bendings are produced on the surface by the pressure of the
ribs, but owing to the elasticity of the wood, which is below, these bendings
disappear nearly entirely again, after the pressure has ceased.
The elastic effect, which is produced here by the thicker layer of the wood may
of course be obtained also by a peculiar clastic base plate.
The effects which are produced, will take place on the surface in the same
manner as also in small boards or wood pieces in which the bendings do not take
place through the whole thickness of the same, when instead of one fluted roller,
two fluted rollers are used.
Only as far as the ribs of the rollers effect a stronger bending, a disintegration
will take place, and it is immaterial whether in the case of two fluted rollers the
ribs of one roller are opposite to the ribs or to the grooves of the other roller,
provided that there is sufficient quantity of wood between the two rollers for
allowing the bendings owing to the elasticity of the wood. As with these pressures
only smaller bendings of the wood are produced, the softening and disintegrating
process will go on much slower than when the ribs act as above described upon
the intermediate spaces.

page_text: In thicker wood pièces the fluted rollers press upon the deeper layers only in
such a manner, that they compress the wood a little, whilst owing to the elasticity
of the wood, the ribs do not produce any effect, and in consequence cannot
produce any softening and disintegration.
When in lieu of the fluted rollers, fluted plates are used, essentially the same
results are produced; one plate may in this case also be replaced by elastic
wood or any other elastic. body. The so called soft woods are particularly suit-
able for this working of the surface, while hard wood offers, on account of the
smaller amount of elasticity, greater difficulties.
The softened and still more the disintegrated wood does no longer adhere
firmly together sidewise by the action of the incrusting substances as does the
original wood, but it will have received everywhere cracks and fine interstices.
These interstices cause the wood when moistened with liquids to take up the latter
by capillary attraction in an exceedingly rapid and abundant manner, which
property is not shown by the ordinary wood not having these interstices.
When the softened woody parts have been impregnated with waterproof liquids,
such as tar, the treated wood, owing to its great absorbing capacity, receives a
proportionately thick layer, capable of resisting the influence of the weather and
affording protection to the wood which is below.
The wood softened on its surface may be used in cylindrical shape in place of
cork for closing bottles and the like.
The obtained fibrous mass shows in comparison with the hitherto known fibre
used in the textile industry quite peculiar properties which can be recognised in
part already with the naked eye.
Whilst in the finer textile fibres an insulation as complete as possible of the
cell is desired and obtained, a separation to such an extent is not advantageous
in the above described process for manufacturing textile fibres, because the wood
cells in the insulated condition are too short for being spun. These wood fibres
consist therefore of bundles of cells and have, owing to the separation of single
or more cells from the bundles, a strange appearance showing the form of
ramification.
By means of the microscope the wood cells separately or in bundles are
always distinctly recognisable and they can be distinguished at once from the cells
of wood cellulose as the former appear as full tubes and the latter as empty
collapsed ones..
The soft masses obtained by the first operation by means of the fluted rollers or
the soft parts of the wood remaining therefrom or formed in other mechanical-or
chemical ways are very advantageously impregnated with a liquid transforming the
hitherto soft masses into brittle hard bodies, which is suitably obtained for instance
by a saturated solution of salts (sodium sulphate, mineral salt, and the like).
The wood is converted by these means from the tough mass difficult to be
transformed into a pulverulent condition, into a brittle body easily pulverised, and
it is capable now of being rubbed, stamped, ground or crushed with a pro-
portionately small amount of power into a 'fine powder.
The good absorption of the impregnating liquid is favoured by the numerous
produced cracks and by the fact, that by the latter the numerous cavities of the
wood have become accessible for the absorption of the liquid.
The salts are removed by means of lixiviating apparatus, and they are recovered
in a solution fit for being used again. The wood powder which is impregnated
with water is used after the water has been partially or entirely removed, in a wet
or dry state, in place of mechanically-prepared wood pulp in the manufacture of
paper and so on.
In the same manner as above described the whole waste resulting from the
modes of working wood is treated, such as not-disintegrated wood shavings, saw
dust and the like. But it is here to be taken into consideration, that the not-
softened woody mass does not absorb a proportionately large quantity of
impregnating liquid and that for this reason it is not reduced as easily as the

page_text: softened mass. In this case it is suitable to repeat the impregnation several
times.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is-
:
1. The treatment of wood or woody parts of plants for obtaining soft wood or
fibres capable of being spun consisting in working thin small wood boards or small
particles of wood either in a dry condition or impregnated with liquids in particular
with diluted sulphurous acid, by means of rollers having continuous or interrupted
ribs in the direction of their length, the said rollers working together in pairs so
arranged that the ribs of one roller are mainly opposite to the intermediate spaces
of the ribs of the other roller, so that the longitudinal fibres of the wood are bent
or cracked with an undulating action substantially as described.
2. For carrying out the process referred to in Claim 1, a rolling machine such
as herein described with reference to Figures 2, 3 and 4 of the drawings consisting
of pairs of rollers having longitudinal ribs rounded off, the lower roller being
actuated by a driving shaft F common to all and bevil wheels E, while the upper
roller is pressed downwards by an elastic medium K.
3. In combination with the process referred to in Claim 1, the substitution for
the longitudinally fluted rollers referred to in Claim 1, of pairs of plates having
parallel ribs which may also be interrupted, the ribs and grooves being also situated
opposite to each other substantially as described.
4. In combination with the process referred to in Claim 1, the substitution for
the action of longitudinally fluted roller or of the plate having parallel ribs
according to Claims 1 and 3 of the elastic counter-pressure of deeper wood layers
or other elastic base plate arranged under the wood to be worked, substantially as
described.
5. The simultaneous manufacture of a soft woody mass and of fibres capable
of being spun from coniferous trees by loosening the lateral adhesion of the
fibres by means of rolling, so that the clearer wood parts difficult to be disintegrated
of the annual rings still remain soft, while the darker parts are disintegrated,
substantially as described.
6. The method of preventing on the surface of the small wood boards fractures
which may be produced in carrying out the process referred to in the Claims 1, 3,
4 and 5, by placing one or more small wood boards one above the other while
putting the projecting darker parts of the annual rings towards the outside
substantially as described.
7. The detaching of the fibres from wood either worked according to the
processes referred to in Claims 1, 3, 4, 5, and 6 or otherwise softened or also
from unprepared wood, by means of tools having on the working faces sharp or
blunt but rough edges by causing the said tools to travel mainly in the direction
of the fibres, over the wood and by separating by these means a portion of the
fibres of the surface, substantially as described.
8. For carrying out the method of operating in Claim 7, the use either of a
machine consisting of a carriage c having knives e moving over a plate furnished
with cards, or of a machine consisting of advancing rollers and of rollers having
sharp ribs effecting the detaching of the fibres substantially as described.
9. The further working of the fibrous masses obtained according to Claims 1
to 8 in a somewhat wet condition by means of cards, if desired in moistening with
oil, for manufacturing textile fibres substantially as described.
10. The product obtained by the described process, characterised by long fibres
having ramifications consisting of short cells arranged side by side and showing
when seen through the microscope, the wood cells in their original condition.
11. The conversion of the woody product either softened according to the
Claims 1 to 5 or only of the woody residues of the same or of other chemically
or mechanically softened or not softened woody parts of plants, in particular of

page_text: wood waste, into a pulverulent, mass by impregnating the said substances with
liquids capable of being converted into brittle bodies and by subjecting this
impregnated wood after it has become brittle, to a mechanical reducing process,
substantially as described..
"
:
ABEL & IMRAY,
Agents for the Applicant.