Year: 1898

page_text: I, WILLIAM PHILLIPS THOMPSON, FCS., MIME, of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Birmingham, in the County of
Warwick, and 322, High Holboin, in the County of Middlesex, Civil Engineer, do
hereby declare the nature of this invention to be as follows
-
In making cane chains and the like it has become customary for some time to dye
the cane employed in order to thereby obtain special artistic effects As however
the natural cane is very variously coloured it must be bleached before being dyed,
at least with the exception of the very clearest solis In the natural Bengal
oi lattan cane three different layers exist, namely, fist the inner core, the 60-called
pith, consisting of woody substances, secondly a layer only partially composed
of organic substance and strongly impregnated with silicic acid, the so-called bast or
bark, and finally a smooth polished or glazed outer course composed almost
exclusively of pure silicic-acid
Seeing that in the bleaching of the cane it has been found that the outer lay".
of silica as well as the bast which is thoroughly permeated with silicic-acid in
a natural condition are practically unattackable in the bleaching bath, the con-
clusion was arrived at that in the manufacture of coloured goods the treatment
must always commence with the complete removal of the silicic acid
The present invention starts from the point of view that the removal of the
silicic-acid in the processes hither to employed must be regarded as a necessary
evil, not only because it offers great technical difficulties, but above all things
because the layer of silica must be regarded as a very valuable constituent of the
cane, as owing to its fine natural polish and its capability of resisting almost all
chemical and mechanical influences it adds not inconsiderably to the beauty and
durability of the cane While therefore the process of treatment hither to adopted
for the cane has been limited, after the removal of the layer of silica, to bleaching
superficially the layer of hast lying immediately beneath the same, the inventoi
of the present process has endeavoured to leave the natural layer of silica un-
attacked or unaffected, and to produce the bleaching and dyeing in such a way
C
037

page_text: that the whole thickness of the layer of bast lying beneath it is entuely bleached
and dyed through, which was hitherto regarded as impossible
The measures adopted for this must be varied according to whether it 18 a
question of making the so-called weaving cane, that is to say, the mechanically
diawn off upper layer of the cane or 10d, or of treating the natural law product
Even in the latter case it is not dithcult to bring the bleaching liquid from the
interior in contact with the layer of last, because the Bengal cane as is well known
1s longitudinally extremely porous and may be comparatively easily filled with
liquid with the use of slight pressure It however this process 18 followed, the
result is that precisely the upper layers which are permeated with silicic-acid arc
not attacked by the bleaching substance It the bleaching process be continued
long enough a thorough bleaching can be obtained, but as the bleaching fluid
exeits a disintegrating action on the fibies, those parts of the woody fibie in which
the bleaching action has already started at the commencement of the operation
are entirely decomposed when the treatment is continued for too long a period
The bleaching must thus be cared on for a given time and therefore care must
be taken that a bleaching action may be exerted simultaneously on all parts of the
cane from the start of the operation.
Sometimes the cane 18
For this object the inventor employs various means
brought in closed vessels into the bleaching bath and exposed to great vanations
of pressure in order to saturate it thoroughly from the commencement
As however the layer of bast permeated with silicic-acid 16 very slightly permeable
in a transverse direction it has been found to be preferable to subject the cane to a
chemical treatment in addition to the mechanical treatment by variations of
pressure, the object of the chemical treatment being to open the pores of the cane
in such a way that they allow free access to the subsequent bleaching
For this object a treatment with alkaline solutions, preferably solutions of
potash compounds has been found particularly suitable, but care must be taken
that the concentrations and temperatures of these solutions are not made so great
that a solution of the layer of silica itself takes place if for artistic reasons it
be desired to obtain intentionally a dull surface, the layer of silica may be easily
attacked to any desired degree by a suitable raising of the temperatures or the
concentrations in the preliminary treatment
The following proportions have been found particularly suitable for the solutions
for this preliminary treatment of the cane: -
1. A 6-10 % solution of potash, which is allowed to act fiom 2-24 hours at
a temperature of about 600.
2. A 10-50% solution of silicate of potash which 18 allowed to act from
2-24 hours at a temperature of about 60
3 An approximate 6% solution of hydrate of potash which is allowed to act cold
for about 12-24 hours.
If so-called weaving cane is to be made by the present process it 18 preferable
to first split the cane and then subject it to the above mentioned preliminary
tieatment in which case a mechanical treatment by variations of pressure may be
entirely dispensed with Said alkaline solutions may also be added directly to the
bleaching bath
First,
The inventor has found that the treatment of Bengal cane with alkaline solutions
This process 89
has already been described with the object of removing the silica
18 well known has not been worked practically mainly for two reasons
the energetic treatment with soda necessary for removing the silica had a deleterious
action on the mechanical properties of the fibres, and secondly, any alkalme
treatment produced a strong brown colouring of the cane which in the bleaching
processes hither to employed could not be entirely removed but imparted a yellowish
effect to the subsequent dyeing which did not aut the taste of the market If
the bleaching was then further continued the colour of the cane took on a greyish
tone which was also undesirable
The inventor has found that on the one hand a treatment with weak alkali, which

page_text: as necessary in order to open the pores, does not appreciably affect the mechanical
properties of the cane, and on the other hand the formation of the undesirable
Eo-called yolk-of-egg colour is to be essentially described to an unequal bleaching
of the different layers, as the laver lying under the surface is essentially more
slowly attacked than the other layers
If however on the other hand care be taken, as is intended in the present process,
hat the bleaching liquid from the start can simultaneously attack all layers of
the cane, a corresponding complete and even bleaching through is obtained, and
the formation of the yolk-of-egg colom is avoided The inventor has also observed
that in the use of potash compounds instead of the soda hitherto employed in the
alkaline removal of the silica, the deleterious yolk-of-egg colour did not arise to the
same extent although at first a somewhat considerable browning of the cane
was obtained
By the means herein before described the possibility is thus afforded, which was
hitherto not recognised, of completely bleaching through the desilicated cane
and a new technical effect is thereby produced in that any sort of cane of no matter
how dark a natural colour, may he bleached through to the same degree of cleaness
so that any subsequent soiting may be entirely dispensed with
Dated this 6th day of June 1898
An Improved Process for Bleaching and Dyeing Glazed or Smooth
Cane.
A communication by II C MEYER, Junior, of Harbuig, in the Empire of Germany
I, WILLIAM PHILLIPS THOMPSON, FCS, MIME., of the Agency for Foreign
Patent Solicitors, 6, Lord Street, Liverpool, and 6, Bank Street, Manchester, both
in the County of Lancaster, 118, New Street, Bumingham, in the County of
Wai wick, and 322, High Holborn, in the County of Middlesex, Civil 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 -
In making cane chairs and the like it has become customary for some time to dye
the cane employed in order to thereby obtain special artistic effects As however
the natural cane is very variously coloured it must be bleached before being dyed,
at least with the exception of the very clearest bolts In the natural Bengal
or 1attan cane three different layers exist namely, first the inner core, the so-called
pith, consisting of woody substances, secondly a layer only partially composed
of organic substance and strongly impregnated with silicic acid, the so-called bast or
bark, and finally a smooth polished or glazed outer course composed almost
exclusively of puie silicic-acıd
Seeing that in the bleaching of the cane it has been found that the outer layer
of silica as well as the bast which is thoroughly permeated with silicic-acid in
à natural condition are practically unattackable in the bleaching bath, the con-
clusion was arrived at that in the manufacture of coloured goods the treatment
must always commence with the complete removal of the silicic acid.

page_text: 1
وام
The present invention starts from the point of view that the removal of the
silicic-acid in the processes hither to employed must be regarded as a necessary
evil, not only because it offers gicat technical difficulties, but above all things
because the layer of silica must be regarded as a very valuable constituent of the
cane, as owing to its fine natural polish and its capability of resisting almost all
chemical and mechanical influences it adds not inconsiderably to the beauty and
durability of the cane. While therefore the process of treatment hitherto adopted
tor the cane has been limited, after the removal of the layer of silica, to bleaching
superficially the layer of bast lying immediately beneath the same, the inventor
of the present process has endeavoured to leave the natural layer of silica un-
attacked or unaffected, and to produce the bleaching and dyeing in such a way
that the whole thickness of the layer of bast lying beneath it is entuely bleached
and dyed through, which was hitherto regarded as impossible.
The measures adopted for this must be varied according to whether it 18 a
question of making the so-called weaving cane, that is to say, the mechanically
diawn off upper layer of the cane or 1od, or of treating the natural law product
Even in the latter case it is not difficult to bring the bleaching liquid fiom the
interior in contact with the layer of bast because the Bengal cane as is well known
18 longitudinally extremely porous and may be comparatively easily filled with
liquid with the use of slight pressure It however this process is followed, the
result is that precisely the upper layers which are permeated with silicic-acid aie
not attacked by the bleaching substance If the bleaching process be continued
long enough a thorough bleaching can be obtained, but as the bleaching fluid
exeits a disintegrating action on the fibres, those parts of the woody fibre in which
the bleaching action has already started at the commencement of the operation
are entirely decomposed when the treatment is continued for too long a period
The bleaching must thus be carried on for a given time and therefore care mist
be taken that a bleaching action may be exerted simultaneously on all parts of the
cane from the start of the operation
"
ני
Sometimes the cane 18
For this object the inventor employs various means
brought in closed vessels into the bleachung bath and exposed to great variations
of pressure in order to saturate it thoroughly from the commencement.
By the term variations of pressure," an increase of pressure and a return to
the normal pressure is to be understood The pressure may be increased up to
6 atmospheres, thus, an increase of pressure takes place, the pressure is then again
suspended and once more increased The frequency of this change and the time to
which the material is exposed to it depends on the quality of the cane. In thick
cane and cane having a thick layer of silica a longer time is necessary for the action
than is the case with thin canes and such canes as have only a thin layer of
silica
With cane of the ordinary constitution with an average quality such as 18
generally sold commercially, the pressure is raised to 5 atmospheres for which about
half an hour is necessary, until the pressure of the air has risen to the amount
indicated The pressure is maintained at this height for about 3 or 4 hours,
when the pressure is then suspended and allowed to descend to the ordinary
atmospheric pressure The time occupied for reducing the pressure of 5 atmo-
spheres to the ordinary atmospheric pressure usually amounts to a quarter of an
hour. The pressure is then again raised to about 5 atmospheres and maintained
at that for about three hours, and it is then again allowed to descend This increase
and decrease of the pressure is repeated as many times as is necessary until the cane
18 thoroughly bleached through The whole process requires for ordinary
commercial cane about 18 hours
The colour of the original cane is also an influencing cause, as dark coloured
The necessary conclusions
canes require a more thorough treatinent than pale ones
as to what pressure is to be employed may thus be easily ascertained by the
workmen taking from time to time a sample of the cane out of the vat and
examining it to see whether the thorough bleaching or colouring has taken place.

page_text: As however the layer of bast permeated with silicic-acid is very slightly permeable
in a transverse direction it has been found to be preferable to subject the cane to
a chemical treatment in addition to the mechanical treatment by variations of
pressure, the object of the chemical treatment being to open the pores of the cane
in such a way that they allow free access to the subsequent bleaching
For this object a treatment with alkaline solutions, preferably solutions of
potash compounds has been found particularly suitable, but care must be taken
that the concentrations and temperatures of these solutions are not made so great
that a solution of the layer of silica itself takes place If for artistic reasons it
be desired to obtain intentionally a dull surface, the layer of silica may be easily
attacked to any desired degree by a suitable raising of the temperatures or the
concentrations in the preliminary treatment
An approximate 6% solution of hydrate of potash which is allowed to act cold
for about 12-24 hours has been found particularly suitable.
If so-called weaving cane is to be made by the present process it is preferable
to first split the cane and then subject it to the above mentioned preliminary
treatment, in which case a mechanical treatment by variations of pressure may be
entnely dispensed with Said alkaline solutions may also be added directly to the
bleaching bath.
The addition of the alkaline solutions to the bleaching bath varies according to
circumstances from 15 to 2 per cent
The inventor has found that the treatment of Bengal cane with alkaline solutions
has already been described with the object of removing the silica This process 89
is well known has not been worked practically mainly for two reasons First,
the energetic treatment with soda necessary for removing the silica had a deleterious
action on the mechanical properties of the fibres, and secondly, any alkaline
treatment produced a strong brown colouring of the cane which in the bleaching
processes hitherto emploved could not be entirely removed, but imparted a yellowish
effect to the subsequent dreing which did not suit the taste of the market
If
the bleaching was then further continued the colour of the cane took on a greyish
tone which was also undesirable
The inventor has found that on the one hand a treatment with weak alkali, which
is necessary in order to open the pores, does not appreciably affect the mechanical
properties of the cane, and on the other hand the formation of the undesirable
so called yolk-of-egg colour is to be essentially ascribed to an unequal bleaching
of the different layers, as the layer lying under the surface is essentially more
slowly attacked than the other lavers
If however on the other hand care be taken as is intended in the present process,
that the bleaching liquid from the start can simultaneously attack all layers of
the cane, a corresponding complete and even bleaching through is obtained, and
the formation of the yolk-of-egg colour is avoided The inventor has also observed
that in the use of potash compounds instead of the soda hitherto emploved in the
alkaline removal of the silica, the deleterious volk-of-egg colour did not arise to the
same extent although at first a somewhat considerable browning of the cane
was obtained
By the means herein before described the possibility 18 thus afforded, which was
lutherto not recognised, of completely bleaching through the non-desilicated cane
and a new technical effect is thereby produced in that any sort of cane of no matter
how dark a natural colour, may be bleached through to the same degree of clearness
so that any subsequent sorting may be entirely dispensed with
Having now particularly described and ascertained the nature of the said
invention and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is..
1 A process for bleaching and dyeing cane, characterised by the non-desilicated
cane being entirely bleached through by the bleaching fluid having equal access
simultaneously to all layers of the cane by the use of variations of pressure or by

page_text: a preliminary chemical treatment preferably with alkaline solutions or by the use
of both means combined, substantially as herembefore set forth.
2 In a process such as described for bleaching and dyeing cane, subjecting the
non-desilicated cane before bleaching and dyeing to a 12-24 hours treatment with
an approximate 6% cold solution of hydrate of potash and then completely
bleaching and dyeing it through, substantially as set forth
3 In a process such as described for bleaching and dyeing cane, bleaching and
dyeing the non-desilicated cane entuely through in a bleaching and dyeing bath
to which an alkaline solution has been added
Dated 13 1041. 1...
N11000