Improvements in the Process of Making Soaps.
Year: 1892

page_text: Date of Application, 18th May, 1892
Complete Specification Left, 18th Mar., 1893-Accepted, 18th May, 1893
PROVISIONAL SPECIFICATION.
Improvements in the Process of Making Soaps.
ROBERT HUGH FORSYTHE FINLAY of Willesden, Holywood, in the County
of Down in Ireland do hereby declare the nature of this invention to be as
follows:-
My invention consists in the manufacture of common & toilet soaps without the
use of caustic soda or potash except what may be added to bring the soaps to a
desired strength.
For the purpose of making soda soap I act on the ammonium salts of fatty or
other similar acids, which I may call ammonium soap, with sodium chloride or other
salt of sodium by boiling and so inducing a chemical reaction whereby are formed
soda soap and at the same time ammonium chloride or other salt of ammonia
corresponding with the salt of sodium first employed.
The soda soap, glycerine, and ammonia may be separated from the liquid by any
of the ordinary methods.
I may in some cases combine the process of making ammonium soap with that
for its conversion into soda soap by boiling tallow or other similar material with
ammonia and sodium chloride or other salt of sodium in a closed vessel, under
pressure, and I may also combine therewith the process for the recovery of the
ammonia by the use of lime or other base in which case a salt of ammonium may
be used instead of ammonia.
For the purpose of making potash soap I employ a similar process substituting a
salt of potassium for salt of sodium.
Dated this 17th dor of Mov 1900
HYNDMAN & DICKSON,
6, Chichester Street, Belfast, Agents for Applicant.
COMPLETE SPECIFICATION.
Improvements in the Process of Making Soaps.
1, ROBERT HUGH FORSYTHE FINLAY, of Willesden Holywood, in County
Down, Ireland, 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 :-
My invention relates to soap making and has for its chief object to manufacture
soaps from salts of sodium and potassium other than the hydrates, caustic soda or
caustic potash except what may in some cases be added of these latter to bring the
soaps to the desired strength.
According to my invention I act on the ammonium salts of fatty acids or the
like, which salts I will call ammonium soap, with any cheap soluble salt of sodium.
A chemical action then takes place in which the sodium displaces the ammonium
forming a sodium soap and a salt of ammonium corresponding to the sodium salt
employed. The soda soap and ammonia may then be separated from the liquid by
any well known method.
As an example, a suitable ammonium soap for my purpose is formed by acting
on oleic acid with an aqueous solution of aminonia. I then according to my
invention boil this ammonium oleate with sodium chloride, whereupon sodium
oleate that is to say a soda soap, and ammonium chloride are formed.
I sometimes combine the process of making the ammonium soap with that of
converting it into soda soap by boiling tallow or other soap-producing substance

page_text: with ammonia and a sodium salt.
I find it advantageous to carry on this operation
in a closed vessel, or in a series of pipes, and in some cases under pressure.
For example, I boil tallow and sodium chloride or other sodium salt with an
aqueous solution of ammonia in a closed vessel under a pressure of about
9 atmospheres at a temperature of about 350° Fah. If a less pressure is used the
saponification takes a longer time. I have found the following proportions suitable.
namely,
namely,
100 lbs. tallow
30 lbs. sodium chloride and
40 lbs. to 80 lbs. of commercial ammenia, containing about 20% of NH³.
If other salts of sodium are used the amount required will be different depending
on the proportion of sodium in the salt employed.
I
may also usc, instead of a sodium salt, a mixture of sodium and potassium salts,
or a mixture of a sodium salt with any inactive substance.
When I desire to make a potash soap, I use a common soluble potassium salt
instead of a sodium salt for acting on the ammonium soap or upon the soap
producing substance in presence of ammonia as hereinbefore described.
In some cases I use alcohol or other suitable solvent to facilitate the chemical
reactions.
The sodium and potassium soaps thus produced by my process contain no free
caustic soda or potash but may contain some unconverted ammonium soap or free
fat, that is to say, the saponification of the soap-making substance may not be
complete. In order to complete the saponification, and render the soap alkaline if
desired, I may treat the same with caustic soda or caustic potash or their
carbonates.
In potash soaps obtained by my improved process no glycerine is found; this is,
in general, not the case with ordinary potash soaps.
By my processes of soap-making I avoid altogether or to a large extent the use
of caustic soda or caustic potash which are expensive forms of the alkalies, and
make use of ordinary salts such as sodium or potassium chloride or sulphate, for
instance, thereby lessening considerably the cost of production.
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. Converting an ammonium soap into a sodium or a potassium soap, by acting
on the same with a salt of sodium or potassium as the case may be, substantially as
described, for the purpose specified.
2. The manufacture of soda or potash soap by. acting on a fat or soap-making
substance with a sodium or potassium salt, aud ammonia, with or without other
substances, substantially as described.
3. The improved processes of making soaps as hereinabove described.
Dated this 18th day of March 1893.
ROBERT FINLAY.
Haseltine, Lake & Co.,
45, Southampton Buildings, London, Agents for the Applicant.