Improvements in the Manufacture of Cellulose Pulp.
Year: 1893

page_text: Date of Application, 20th Jec., 1993
Complete Specifcation Left, 15th Sept., 1894-Accepted, 20th Oct.,
1894
PROVISIONAL SPECIFICATION.
Improvements in the Manufacture of Cellulose Pulp.
I, JAMES YATE JOHNSON, of 47 Lincoln's Inn Fields, in the County of
Middlesex, Gentleman, do hereby declare the nature of this invention (which
has been communicated to me from abroad by Paul Sohège, of 58 bts Chaussee
d'Antin, Paris, in the Republic of France, Manufacturer,) to be as follows:-
The employment of gelatine in the manufacture of paper or card for the purpose
of causing the fibres of the cellulose to adhere presents several disadvantages of
which the principal are the following viz. :-
Pulps sized with a large proportion of gelatine in order to obtain hard or stiff cards
are subject to rapid fermentation, which prevents them from being preserved in
good condition and when the manufactured card is dry it loses its hardness and is
liable to putrefaction if exposed to damp.
The sizing with gelatine of a cellulose intended for the manufacture of card can
only be effected in warm receivers and the state of fluidity of the solution of
gelatine varying according to the season at the time of the drainage of the sheets
of pulp, the liquid extracted carries with it variable quantities of gelatine which
produces an unequal sizing of the cellulose.
The compression to which the sheets or articles are subjected not being uniform
this also produces inequalities in the sizing of the manufactured goods.
The liquids resulting from drainage and pressing in the methods employed
heretofore may be used for the sizing of fresh pulps, but although the waste of the
gelatine may thus be obviated the products possess the same tendency to
fermentation and present the same irregularities of sizing.
The method of treatment forming the subject of the present invention has for its
object obviating the disadvantages herein before described.
The said method or process consists in sizing a cellulose pulp containing tannin
with gelatine whereby the following results are obtained viz. :
Under the influence of tannic acid the gelatine is precipitated in insoluble flakes
on the fibres of the cellulose and there is obtained an imputrescible pulp not liable
to fermentation and not liable to be injuriously affected by the action of moisture.
The gelatine adhering to the fibres of cellulose and covering them at the time
of its precipitation, the whole of the size employed adheres to the pulp and the
exact amount of sizing required is obtained and the sizing is uniformly
effected.
At the time of the pressing of the pulp there is produced the same phenomena
as when the pulp is coloured with insoluble colours precipitated on the fibres. The
drainage water and that expelled by pressing are discharged clear and free from
gelatine, the packet of sheets or the pressed articles preserving the required weight
of gelatine uniformly in all parts.
Alum may be added to the gelatine in order to hasten the precipitation of the
gelatine and economise the tannic acid.
Resin soap, colours, or other substances usually employed may be added to the
pulps if desired.
Certain kinds of cellulose especially those obtained from tanning barks naturally
contain tannic acid and are capable of precipitating the gelatine in the soluble and
imputrescible state. Spent tan contains sufficient tannic acid to effect this
precipitation and this tan having already undergone operations which facilitate the
removal of its fibres it may be employed with advantage with a view to
manufacturing sheets or articles of card according to this invention.

page_text: In case the spent tan contains an insufficient amount of tannic acid or when it is
desired to add a proportion of non-tannic cellulose to the cellulose consisting of tan
deprived of fibre there may be added to the previously mentioned materials afresh
supply of spent tan or a certain proportion of new tan, or a certain proportion of
the liquid obtained by the systematic exhaustion of tans in order to obtain pulps 5
containing a sufficient quantity of tannic acid to precipitate all the gelatine
necessary for the sizing of the cards or other articles to be manufactured.
Dated this 20th day of December 1893.
COMPLETE SPECIFICATION.
Improvements in the Manufacture of Cellulose Pulp.
1, JAMES YATE JOHNSON of 47 Lincoln's Inn Fields in the County of
Middlesex Gentleman do hereby declare the nature of this invention (which has
been communicated to me from abroad by Paul Sohége of 58 Chaussee d'Antin
Paris in the Republic of France Manufacturer) and in what manner the same
is to be performed to be particularly described and ascertained in and by the
following statement :-
The employment of gelatine in the manufacture of paper or card for the purpose
of causing the fibres of the cellulose to adhere presents several disadvantages of
which the principal are the following vizt. :-
Pulps sized with a large proportion of gelatine in order to obtain hard or stiff
cards are subject to rapid fermentation which prevents them from being preserved
in good condition and when the manufactured card is dry notwithstanding the
insolubility of the gelatine which it contains it loses its hardness and is liable to
putrefaction if exposed to damp on account of the property which the gelatine
possesses of swelling in the presence of cold water. The sizing with gelatine of a
cellulose intended for the manufacture of card, can only be effected in warm
receivers and the state of fluidity of the solution of gelatine varying according to
the season at the time of the drainage of the sheets of pulp, the liquid extracted
carries with it variable quantities of gelatine which produces an unequal sizing of
the cellulose.
The compression to which the sheets or articles are subjected not being uniform
this also produces inequalities in the sizing of the manufactured goods. The liquids
resulting from drainage and pressing in the methods employed heretofore may be
used for the sizing of fresh pulps but although the waste of the gelatine may thus
be obviated the products possess the same tendency to fermentation and present the
same irregularities of sizing.
The method of treatment forming the subject of the present invention has for its
object obviating the disadvantages hereinbefore described.
The said method or process consists in sizing a cellulose pulp containing tannin
with gelatine whereby the following results are obtained vizt.: Under the influence
of tannic acid the gelatine is precipitated in insoluble flakes on the fibres of the
cellulose and there is obtained an imputrescible pulp not liable to fermentation and
not liable to be injuriously affected by the action of moisture.
The gelatine adhering to the fibres of cellulose and covering them at the time of
its precipitation, the whole of the size employed adheres to the pulp the exact
amount of sizing required is obtained and the sizing is uniformly effected notwith-
standing changes in the external temperature or in the pulp itself arising from the
variable time occupied by the operations.
At the time of the pressing of the pulp there is produced the same phenomena as
when the pulp is coloured with insoluble colours precipitated on the fibres. The
drainage water and that expelled by pressing are discharged clear and free from

page_text: gelatine, the packet of sheets or the pressed articles preserving the required weight
of gelatine uniformly in all parts.
Alum may be added to the gelatine in order to hasten the precipitation of the
gelatine and economise the tannic acid.
Resin soap, colours, or other substances usually employed may be added to the
pulps if desired.
Certain kinds of cellulose especially those obtained from tanning barks naturally
contain tannic acid and are capable of precipitating the gelatine in the soluble and
imputrescible state. Spent tan contains sufficient tannic acid to effect this
precipitation and this tan having already undergone operations which facilitate the
removal of its fibres it may be employed with advantage with a view to
manufacturing sheets or articles of card according to this invention.
"
In case the spent tan contains an insufficient amount of tannic acid either after the
extraction of the " ooze
or by being uncovered for a long time and exposed to
the action of rain, or if it is desired to add a proportion of non-tannic cellulose to
the cellulose consisting of tan deprived of fibre there may be added to the
previously mentioned materials a fresh supply of spent tan, or a certain proportion
of new tan, or a certain proportion of the liquid obtained by the systematic
exhaustion of tans in order to obtain puips containing a sufficient quantity of tannic
acid to precipitate all the gelatine necessary for the sizing of the cards or other
articles to be manufactured.
Having now particularly described and ascertained the nature of the said inven-
tion and in what manner the same is to be performed I declare that what I
claim is.-
The addition of tannic acid to the cellulose intended for sizing the fibres of
cellulose with gelatine and the employment of celluloses naturally containing tannin
either in a natural state or in the state of tan for making pulp intended for the
production of paper, or card, or articles in card pulp, in which gelatine is insoluble,
imputrescible and very slightly liable to swell and soften by the action of damp
substantially as hereinbefore described.
Dated this 15th day of September 1894..