Powders to Remove Paint and Organic Matters from Wood, Iron, Stone, and other Materials.
Year: 1895

page_text: Date of Application, 8th Mar., 1895
Complete Specification Left, 7th Dec., 1895-Accepted, 11th Jan., 1896
PROVISIONAL SPECIFICATION.
New Powders to Remove Paint and Organic Matters from Wood,
Iron, Stone, and other Materials.
I, GUILLAUME JOSEPH CONRAD MARIE BARON DE LIEBHABER, Engineer,
of 30, Crondace Road Fulham S.W. in the County of London, do hereby declare
the nature of this invention to be as follows :-
The object of this invention is to remove paint & other organic deposits from
wood, iron, stone & other materials. This is done by means of powders, inert
when dry, but which when made into paste of a proper consistency become
caustic by the action of water & act as a substitute for sada or alcali. I have
given the name of "Natrogen to these powders which though differing in their
composition, all generate soda in a caustic state.
"
The first of these powders is made of cryolithe finely ground & slaked lime to
which is added an absorbing inert matter such as china clay or pipe clay or some
other clay, with or without chalk. The proportions should be about 170 parts of
slaked lime to 100 of cryolithe, and absorbing matter more or less according to
the quantity of water desired in the paste & the degree of causticity to result
therefrom.
Another powder is made of fluoride of sodium finely ground or in a pulverulent
state & slaked lime in about equal parts carefully mixed, with the addition of
china or other clay, chalk or some other absorbing matter as aforesaid.
The last kind of powder is made of carbonate of soda, slaked lime & clay or
chalk or a mixture of both. Its efficiency is founded on a curious property of
hydrated soda which I have discovered or noticed, & which is this: Caustic soda
diluted in a quantity of water less than 24 equivalents decomposes carbonate of
lime & consequently, when itself carbonated, is not acted upon by lime. But when
the quantity of water is increased to 24 equivalents i.e. about 7 times the weight
of anhydrous soda it forms a definite compound (NaO 24 HO) with other pro-
perties one, among others, being that when put in contact with carbonate of lime.
it does not act on it, & on the contrary if carbonated (NaO CO, 24 HO), it is
deprived of its carbonic acid & becomes caustic. Water added to this definite
compound does not modify this affinity; on the contrary it makes it more
energetic.
The consequence is that for a mixture of carbonate of soda & lime to become
caustic by the addition of water, the condition is that the quantity of water be a
little over four times the quantity of carbonate of soda (NaO CO₂) & of course
the presence of at least one equivalent of lime is necessary. But I find it generally
more advantageous to bring the proportion of water to 5 times the weight of the.
carbonate or about; for although the caustic soda thus produced is in a more
diluted state (under 16° Beaumé, the maximum corresponding to a little over
4 parts of water to one part of carbonate of soda) the action is more complete &
rapid.
To obtain these proportions a certain quantity of absorbing inert matter like
china clay or other clay with or without chalk has to be added to the mixture, the
quantity to be ascertained for each kind of clay empirically & to be greater or
smaller according to the required degree of concentration of soda. For that
purpose after having intimately mixed dry carbonate of soda (such as
the

page_text: anhydrous carbonate in the ammonia process) with slaked lime in the proportion
of about three parts of carbonate to two of slaked lime, I add water in the pro-
portion of five (more or less as required for the final result) & I mix the china or
other clay or absorbing matter, noting carefully the quantity used until it produces
a rather light paste. I leave it 2 or 3 hours. If it does not thicken or become
firm, I add some more & leave it to itself & so on until I have a paste of the proper
consistency & not thickening. If it does become thick & hard it is a proof that
the quantity of absorbing matter is in excess & I try with a smaller proportion
until I hit upon the proper point. I thus ascertain the exact quantity of absorbing
matter to be added to the mixture of carbonate of soda & lime in order to obtain
a paste of the proper consistency & the exact proportion of water, & I have
only to mix the ingredients in the proportions thus determined as intimately as
possible.
'
This last powder differs from similar powders of an analogous composition by
the mode of preparation which insures mathematically the proportions of the com-
ponents, & particularly of the water in the paste, a condition essential to its
efficiency; & also by the fact that when used (on wood for example) there remains
no lime in a free state, which could injure the material itself or the new paint
afterwards.
Besides this last powder can be improved by mixing it with one of the preceding
powders.
The pastes made with these powders are generally to be applied on the surface
to be cleaned by means of a painter's brush (made of vegetable matter) though
sometimes they may be laid with a trowel or a putty knife.
As soon as the paste has acted on the paint or deposit, particularly on wood, it
is to be removed, sometimes to be used again a second time or even a third time,
& the surface carefully washed.
These powders can be used to remove paint or organic impurities from wood
(doors shop-fronts, furniture etc.) from iron (in iron bridges, railings, ships, railway
carriages etc.) & for household purposes; & generally whenever the application of
caustic soda in a liquid state is inefficient or objectionable.
* Dated this Eighth day of March 1895.
COMPLETE SPECIFICATION.
New Powders to Remove Paint and Organic Matters from Wood,
Iron, Stone, and other Materials..
I GUILLAUME JOSEPH CONRAD MARIE BARON DE LIEBHABER of
30 Crondace Road Fulham in the County of London 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 :-
The object of the invention is to remove paint and other organic deposits from
wood, iron stone and other materials and to cleanse generally. This is done by
means of powders inert when dry, which when made into paste of a proper con-
sistency become caustic under the influence of water and act as a substitute for
soda or alcali. 1 have given the name of Natrogen to these powders which though
differing in their composition all generate when mixed with water, soda in a
caustic state.
The first of these powders is made of cryolithe finely ground and slaked lime
more or less carbonated by exposure to the air. The proportion should be for
two parts of cryolithe, three parts of slaked lime if fresh, more if the lime is
partially carbonated; and five if the lime has been a long time in the air and the
half of it transformed into carbonate..

page_text: Another powder possessed of a great caustic power, and intended to supersede
caustic soda for many purposes, is made of fluoride of sodium finely ground and
slaked lime carefully mixed, about equal parts when lime is fresh, or more and
up to two parts if the lime has been carbonated by its exposure to the air.
Fluoride of potassium may be partially or wholly substituted to fluoride of
sodium, in which case the proportion of lime should be a little less.
The last sort of powder is made of anhydrous carbonate of soda, such as is
produced by the ammonia process, and slaked lime. Its efficiency is conditional
on certain exact proportions and is founded on a curious property of hydrated
soda which I have discovered or noticed, and which is this: Caustic soda diluted
in a quantity of water less than 24 equivalents decomposes carbonate of lime and
consequently, when itself carbonated is not acted upon by lime. But when the
quantity of water is increased to 24 equivalents, a definite compound is formed
(NaO 24 HO) endowed with other properties, one among them being that brought
in contact with carbonate of lime it does not act on it, and on the contrary if
carbonated (NaO CO* 24 HO) it is deprived of its carbonic acid and recovers its
causticity. Water added to that definite compound does not modify this affinity
rather makes it more energetic.
The consequence is that for a mixture of carbonate of soda and lime to become
caustic by the addition of water, the condition is that the quantity of that water
be a little over four times the quantity of carbonate of soda (NaO CO³); and of
course the presence of at least one equivalent of lime is necessary. I find
generally more advantageous to bring the proportion of water to five times the
quantity of carbonate of soda or about: for though the caustic soda thus produced
is in a more diluted state, the action is more complete and rapid, and besides for
the purpose of cleansing, a little lower degree is preferable. An excess of lime
has also been found useful. The preparation of the powder is made to fulfil
those conditions.
Lime is first slaked as usual and abandoned to the air, and stirred at intervals,
for a certain time say a month or more until it is about half carbonated and has
become in fact an hydrocarbonate of lime. It has then increased in weight and
has become more pulverulent. It is then deprived of its stony parts and other
impurities by proper means or sifted if necessary. But this operation is easier
than when lime is freshly slaked. With this carbonated lime, more properly
bydrocarbonate of lime, anhydrous carbonate of soda is intimately mixed, and a
small quantity of permanganate of potash finely ground is added. The proportious
should be, the carbonate of soda supposed entirely dry,
or permanganate or potash.
If, as frequently happens, the carbonate of soda contains hygrometric or
combined water (which should be ascertained by dessication) the quantity of lime
has to be reduced in proportion, and for a salt long exposed to the air and
containing for example to of its weight of water, the quantity of lime must be
brought down to 300 parts for of salt (100 parts). But as the absorbing power
of the lime varies with the quality, degree of fineness, and other circumstances,
it is necessary to submit a sample of the mixture to a direct test, and ascertain that
the actual proportion of water is the right one, generally five to one of salt, and in
case of excess or deficience lessen or increase the quantity of lime.
The proportions of the ingredients being thus determined, they are intimately
mixed, so that no part of the mass be richer or poorer in salt than the other ones,
which is known to be the case when the coloured specks produced by the.
permanganate, on the addition of water, are uniformly spread in the mass.
To use these powders, they are mixed with water and well stirred until a paste
of the proper consistency is obtained and then left to themselves, until the paste.

page_text: thickens and becomes firm, which happens after a short time for the cryolithe and
carbonate powder. For this last a very small quantity of water is sufficient to
restore its fluidity, and it does not generally harden a second time: if it does
another small quantity of water is added until the paste is saturated. For the
cryolithe powder many such additions are necessary and in larger quantities: and
the paste must be left to digest some hours at least.
Fluoride powders are treated in the same manner, water being added until the
paste is saturated.
To remove paint and other thick or hard deposits the paste is applied by means
of a painter's knife or a trowel: for coarse work or thin deposits with a brush.
It is left a sufficient time on the surface, until the matters are either eaten up or
disaggregated the paste is then taken off as completely as possible and the surface
scraped or washed.
:
It is sometimes sufficient to rub the dirty or greasy surface with paste and wash
or wipe off directly; in which case the paste used should be thicker and more
sticking.
When the object is not to remove paint or other deposits, wax, varnish or the
like, but only to cleanse the surface without injuring the paint itself or the soiled
article which ever it may be, or when the deposit is very thin, the powder is placed
in a bag of linen or cotton, or simply wrapped up in a piece of linen or cotton
cloth: The side which is to be held by the hand is introduced in a cover of
india rubber in the form of a cone attached to a handle and protecting the
fingers when moving and pressing the bag. The bag filled with powder is
immersed in water, or the powder may be made into a paste before closing it.
The surface is then rubbed gently with the bag and washed or wiped off
directly with a sponge or a rag, no solid matter being left. The bag has to
be moistened from time to time and the paste renewed when it has become too
hard.
This process will be found useful in a great variety of cases, and constitutes one
of the chief features of the invention.
Those powders can be used in the same way for the purpose of alcalizing water
either for washing, bathing or with any other object. A bag filled with powder
has only to be dipped or squeezed out in the water, before using it.
In
Sometimes the purchaser prefers to have the paste made ready for use.
that case I prepare it at once without going through the stage of powder, which
is a great saving. For that purpose I take a certain quantity of soda (anhydrous),
I dissolve it in five times its weight of water and add slaked lime more or less
carbonated until it makes a paste of the proper consistency. If using crystals of
soda the quantity of water must be one and a quarter that of the crystals or a
little more according to the temperature.
Another method consists in taking
:
12 parts of water
mixing them in an ordinary tub or vat and stirring until the hydratation of the
lime is completed and a proper paste is produced. This paste as well as the
preceding one is forced through a sieve with iron meshes put in wooden casks and
well covered.
Those powders and pastes can be used:
To remove paint and other deposits on wood iron, plaster, stone and other
material:
To cleanse paint or varnish, or any other coating without injuring the paint
itself to cleanse and restore soiled articles as marble and sculpture, iron grates,
furniture, floors railway and other carriages, and to cleanse generally for
household or other purposes:

page_text: To alcalise water as aforesaid, and generally to supersede soda or potash,
whenever their use in a liquid state is insufficient or objectionable.
Having now particularly described and ascertained the nature of my inven-
tion and in what manner the same is to be performed I declare that what I
claim is:
1. The mixture of cryolithe or fluoride of sodium or potassium with hydrated
lime partially carbonated or not.
2. The mixture of anhydrous carbonate of soda, and partially carbonated lime
or hydrocarbonate of lime; the exact proportions of water and soda, and the
mode of preparation insuring those exact proportions, and the addition of
permanganate of potash.
3. The use of those powders and pastes to cleanse painted varnished or otherwise
covered surface without injuring the coating or objects themselves and cleansing
generally by rubbing the surface with a bag or wrapper filled with paste and
leaving no solid residuum.
4. The direct preparation of an alcaline paste as aforesaid.
5. Alcalizing the water with such powders or pastes enclosed in a bag, and
generally superseding soda or potash, to produce alcaline reactions.
Dated this Seventh day of December 1895.
BN. DE LIEBHABER.