IMPROVEMENTS IN THE METHOD OF SHAPING SOAP INTO BARS
Year: 1884

page_text: I CHARLES ROMLEY ALDER WRIGHT Doctor of Science, Consulting Chemist, of
3 Castillain Road, Maida Vale in the County of Middlesex do hereby declare the
nature of my invention for IMPROVEMENTS IN THE METHOD OF SHAPING SOAP
INTO BARS to be as follows:-
"
"
This invention relates to improved devices and machinery for the purpose of.
shaping soap and more especially the better kinds of soap used for toilet purposes,
into bars and tablets.
It is well known that freshly prepared ordinary soap is almost fluid when hot,
but becomes thicker and more stiff on reducing the temperature, and almost solid
on completely cooling and standing. I find that at some particular temperature
somewhat variable with the nature of the soap and with the amount of water
contained therein, melted soap that has been subsequently partially cooled possesses
a convenient degree of plasticity so that by applying pressure to the soap in a
suitable receptacle it can be made to issue in the form of a continuous stream of
substance sufficiently firm in texture to retain its shape and becoming still more
firm on exposure to air and standing. I make use of this observation for the
purpose of devising appliances whereby soap rendered almost fluid by heat can at
one operation be moulded into bars of any required length and of any required
shape in cross section whereby much time is saved as compared with the ordinary
process of casting the soap into blocks and subsequently cutting them up into bars
after cooling and solidifying..
-
In order to effect this purpose I force the soap rendered almost fluid by heat by.
means of any convenient machine adapted for the purpose through one or more
cooling pipes preferably constructed of metal (and more especially of copper on
account of its high power of conducting heat) and cooled either by simple exposure
to air or preferably by being surrounded by a jacket or trough containing water
renewed or otherwise kept constant in temperature as required. The molten soap
is thus cooled and thickened in texture to an extent dependent on the speed with
which the soap is passed through the cooling tubes, their length and diameter, and
the nature and original temperature of the soap. When these circumstances are
duly attended to the cooled soap issues at the far end in a sufficiently firin state to
keep its shape so that the cross section of the bar or rod of soap that issues can be
determined by suitably shaping the orifice or mouth piece from which it issues.
In most cases I find it desirable to employ several cooling tubes of small bore
•

page_text: arranged parallel with one another and communicating at one end with the
reservoir of molten soap to which pressure is applied and at the other with the
wide end of a bell or funnel shaped chamber to the further end of which is affixed
the mouthpiece through which the shaped bar issues: with proper attention to the
speed with which the soap passes through the cooling tubes the different streams of
cooled plastic soap that issue from the different cooling tubes respectively com-
pletely unite and as it were weld together into one uniform mass in the funnel
shaped chamber.
In some cases I find it advantageous to force the molten soap through the cooling
tubes intermittently, just so much fresh molten soap being introduced as will
suffice to displace and move onwards the partially cooled soap contained in the
tubes which are thus refilled with molten soap at each continuance of the forcing
operation, the soap thus introduced remaining stationary in the tubes whilst the
forcing operation is discontinued. A more complete cooling and a greater degree
of solidification is thus brought about by reason of the increased length of time
during which the soap is subjected to cooling influences. When this method of
operating is adopted two or more sets of cooling tubes may conveniently be con-
nected with the forcing arrangement by means of appropriate cocks or valves so
that fresh molten soap can be forced into one set of tubes whilst that in the other
sets of tubes is-stationary and so on alternately.
.
The long bars or rods of soap issuing from the mouth piéces are finally cut into
pieces of suitable length which if required may be further shaped and moulded
into cakes or tablets by any of the well known machines for that purpose.

page_text: "
°
I CHARLES ROMLEY, ALDER WRIGHT; Doctor of Science, Consulting Chemist, of
3 Castillain Road Maida Vale in the County of Middlesex do hereby declare the
nature of my invention for IMPROVEMENTS IN THE METHOD OF SHAPING SOAP.
INTO BARS" and in what manner the same is to be performed to be particularly
described and ascertained in and by the following statement :-
This invention relates to the method of shaping soap and more especially the
better kinds of soap used for toilet purposes, into bars and tablets.
.
It is well known that ordinary soaps when freshly prepared and not dried are
almost fluid when hot, but become thicker and more stiff on reducing the tempera-
ture and almost solid on completely cooling and standing. I find that when hot and
fluid soap is partially cooled to some particular temperature, which varies with the
nature of the soap and with the amount of water contained therein, it thickens in
texture so as to become a semi-solid plastic mass possessing sufficient consistency to
retain any shape into which it may be moulded and becoming still more firm on
complete cooling and standing; and that in consequence it is possible to mould
hot nearly fluid soap into bars by allowing it to pass into a hollow mould or
pipe to which proper cooling agencies are, applied so as to reduce the temperature
of the soap to the necessary extent, the operation being carried on continuously,
that is to say hot nearly fluid soap being from time to time made to flow into the
pipe at one end and passing out at the other end in the form of a thick rod or bar
cooled sufficiently to enable it to retain its shape and rapidly becoming more firm
and "set" on further standing so as to cool completely.
In order to effect this result I force the hot and almost fluid soap by means of
any convenient machine adapted for the purpose through a pipe, preferably made
of metal and as thin in the walls as possible consistent with due strength, this pipe
being cooled by any convenient means, but preferably by being surrounded by
water contained in one or more troughs or jackets and constantly maintained at
such temperatures as may be most suitable to the particular kind of soap employed;
being cooled as required by running in streams of cold water passing out again by
overflow pipes and being warmed if at any time it should be found necessary by
similarly running in hot water or by passing in steam; or heating or cooling
arrangements of any other convenient kinds may be applied; the length of the
pipe, the temperatures of the jackets and the average speed with which the soap
passes through the pipe being so proportioned to one another as just to suffice to
cool the soap to the required extent before emerging. The exact temperatures
length of pipe and speed may vary much according to the nature of the soap and
the amount of water in it. The precise dimensions and shape of the cross section,
of the issuing bar are conveniently regulated by means of a smoothly polished
mouth piece or nozzle attached to the pipe and preferably similar in shape to but,
slightly smaller than the bore of the pipe, so as to constrict and compress the bar.

page_text: of soap a little as it issues. Too great a difference in size between the bore of the
pipe and the orifice of the nozzle should be avoided, otherwise with certain kinds
of soap the bar may become flawed or cracked. When suitable adjustments are
made the moulding of soap into bars in this way is carried out with a saving of
much time and labour and a great diminution in the amount of waste in cuttings
and scraps as compared with the process ordinarily in use, viz, casting the molten
soap into large blocks, which after standing one or more days to solidify are cut up
into slabs and bars either by hand or by cutting and shaping machines devised for
the purpose. The long bars of soap issuing from the mouthpiece are finally cut
into short lengths and stamped or otherwise moulded into tablets by means of any
of the well known devices for the purpose in ordinary use.
In order to effect a due amount of cooling and especially_ with bars exceeding an
inch or thereabouts in thickness it is usually necessary to make the cooling tube
several feet in length; to facilitate internal cleansing the tube may be constructed
not in one piece but in several lengths connected together in any of the ways in
which continuous pipes are ordinarily constructed such as by. socketted junctions or
by flanges bolted together in such fashion that the junctions can readily be undone
as required. Further the separate lengths may each be constructed in two longi-
tudinal halves bolted or otherwise fastened together in such fashion that when
required each length can be taken to pieces and thus every part of the interior of
the tube can be readily accessible for cleansing or polishing if required.
In some cases I find it convenient to employ a compound cooling tube consisting
of a number of tubes of comparatively small bore, that is from say to inch
across at the widest part, arranged parallel with one another in a water trough or
jacket and all cominunicating at one end with the chamber or vessel out of which
the hot nearly fluid soap issues and at the other end with the wider part of a
tapering chamber or portion of the compound tube terminating in a single moulding
-pipe passing through another trough or jacket and supplied with a suitably sized
mouth piece or nozzle to determine the precise shape and cross sectional dimensions
of the bar of soap ultimately formed. The temperature of the trough in which
the series of parallel smaller tubes is immersed is so regulated that the streams of
hot nearly fluid soap made to pass through the tubes emerge therefrom into the
tapering chamber thickened in consistency by partial cooling but still sufficiently
soft to coalesce completely together into one semi-fluid mass in this chamber; this
semi-fluid mass being then further cooled and partially solidified in the single
moulding pipe so as to emerge from the nozzle as a bar of sufficient consistence to
retain its shape; if the temperature of the trough surrounding the series of parallel
pipes is too low, not only is a far greater degree of forcing power requisite to cause
the soap to pass through the tubes, but further in certain cases the streams of
partially cooled soap issuing from the series of tubes are not soft enough to coalesce
thoroughly whilst passing through the rest of the apparatus, so that the-bar finally
produced is liable to crack or break asunder when submitted to the further
operation of stamping. Instead of a series of parallel tubes of smaller bore, an
annular tube may be used surrounded by water externally and supplied also with
water in the central portion or space within the annular tube.
In some cases I find it convenient to force the molten soap through a cooling
tube in a steady continuous stream of nearly constant speed; in other cases it is
preferable to make the stream an intermittent one, molten soap being at more or
less regular intervals allowed to flow into the tube thus displacing and forcing out
before it the partially cooled and solidified soap that had been admitted into the
tube at the previous time when the stream was made to flow. In this way the
soap is alternately stationary in the tube and moving onwards according as the flow
of the stream is broken off or established; a much greater degree of solidification
can be thus effected owing to the longer time during which the soap is subjected to
cooling influences. When intermittent streams are employed it is convenient for
the saving of time to employ two or more similar cooling tubes connected with

page_text: the same receptacle or chamber holding the melted soap by means of cocks or
valves so arranged that the molten soap can at pleasure be made to pass into any
one of the cooling tubes which are then used alternately in regular order; the
melted soap being allowed to pass into the first tube for awhile, then into the
second, that which had already passed into the first tube remaining stationary
therein and so on' in regular order.
The accompanying drawings exemplify arrangements constructed according to
my invention for the purpose of carrying it into effect. Figure I represents a plan
and Figure II a vertical section of a single moulding tube. The tube is constructed
in two nearly equal lengths united together by flanges screw bolts and nuts and
may in the arrangement shown by the drawings be 3 inches in internal diameter,
the diameter of the orifice in the nozzle being 23 inches. Each length of pipe
passes through a trough to hold water; the melted soap enters at the end A being
forced out under the requisite pressure from any convenient receptacle by any
convenient means, such for example as a pump; or a "squirting" arrangement
consisting of a barrel furnished with a piston actuated by manual, steam or
hydraulic power; or an Archimedean screw, or any other machine in ordinary use
capable of propelling a stream of hot fluid matter. This apparatus should be
capable of applying a pressure of say 50 lbs per square inch to the soap although
when the machine is working properly a much less pressure will suffice. The speed at
which the forcing apparatus sends the soap forward should be completely under
control. After passing through the entire length of the cooling pipe the soap
emerges at B through the shaping nozzle or mouthpiece affixed at that end for the
purpose of determining the cross section of the bar. The temperatures of the two
troughs C and D are known by placing thermometers therein or determined in any
other convenient way and are regulated and kept constant by admitting streams of
cold or hot water or steam as may be required.
In working the machine if it be found that the soap as it issues from the orifice
is too stiff so that too much force is required to carry it forward, the temperatures
of the jackets are somewhat raised either by running in hot water or steam or by
lessening the supply of cold water, and the forcing apparatus is caused to work
somewhat faster. If on the other hand the soap presents itself at the orifice in too
soft a condition the forcing apparatus is temporarily stopped and the temperature
of this jacket is somewhat lowered by running in cold water.
Figure III represents a plan of a compound cooling tube consisting of a number
of parallel tubes A. A. A. surrounded by water contained in a trough B and com-
municating at the end C with the receptacle from which the soap issues, and at the
end D with a tapering chamber E to the narrower end of which is attached the
single moulding tube F surrounded by water in a second trough G and terminating
in a nozzle H as before.
By my invention much time and labour is saved as compared with the ordinary¯
process of casting the soap into blocks and subsequently after cooling and solidi-
fying cutting the blocks up first into slabs, & then into bars, and subsequently
shaping these bars to any required cross section by hand or by machines devised
for the purpose.
Also the production of scrap required to be remitted and thereby involving loss
of time labour and quality is reduced from a large fraction of the whole in the
ordinary way of working to an amount practically inconsiderable when my
invention is properly carried into effect.
Having now described the nature of my said Invention and-in what manner
the same is to be performed I desire it to be understood that I do not claim as
my invention the use of forcing or moulding appliances for the purpose of squeezing
by means of great pressure solid soap into bars without the aid of heat or the
application of cooling appliances but what I claim is
(1.) The method herein described of shaping soap into bars by the aid of heat
and by cooling the soap being forced when in an almost fluid state into a passage

page_text: :
in which it is cooled and being so caused to issue from the passage through an
orifice in a cooled-condition and sufficiently firm and set to retain its form:
(2) Shaping soap into bars substantially as herein described:
Dated this 31st day of March 1803
+
CARPMAEL & Co.,
Agents for the Applicant.