Improvements in the Treatment of Gums and the Preparation of Varnishes therefrom.
Year: 1891

page_text: Date of Application, 23rd Apr., 1891
Complete Specification Left, 13th Jan., 1892-Accepted, 20th Feb., 1892
PROVISIONAL SPECIFICATION.
Improvements in the Treatment of Gums and the Preparation of
Varnishes therefrom.
I GEORGE HAND SMITH of 71 Edith Road West Kensington in the County
of Middlesex, Doctor of Medicine do hereby declare the nature of this invention
to be as follows :-
This invention has for its object the treatment of gums in order to obtain varnishes
therefrom without employing separate fusion of those gums previous to their
solution in the solvent medium.
In carrying out my invention I design to utilize the property which I have
discovered by experiment-that gums of greater solubility, or more easily solved
gums, are in different, or relative, degrees available for use, as solvents-or aids to
solution or completer solution of harder or more refractory gums; or one class
of gum is used as an aid in solution of another class or description of gum in the
presence of a suitable solvent medium-such as linseed oil or other oil, turpentine-
capable of holding the gums (including gum resins) in solution or combination,
whilst conducting the operation at low degrees of temperature-that is to say at
temperatures sufficiently low not to cause injury in colour or texture, or loss of
weight to the gums to any serious extent in the resultant production. For instance
this combination or reduction of gums may be effected at a temperature as low as
(say) about 250° Fahr.
As instances of soft gums, or resins I may employ, gum damar and ordinary
commercial resins of ready solubility; or a small quantity of the products of
distillation of those gums and resins, now very commonly wasted, or allowed to
pass off unutilised in course of manufacturing varnishes as at present carried on.
As harder gums or gum resins kauri, copal, anime, amber or other like gums.
Supposing kauri gum to be desired to be reduced to solution for use in making a
varnish a small quantity of gum damar, so relatively insignificant in quantity as
not to have any prejudicial effect on the resultant varnish, is dissolved in, say,
linseed oil. This solution is then added in a suitable vessel to a quantity of kauri
gum and the desired quantity of, say linseed oil suitable for forming the solution of
the gum is added, and upon sufficient heat, say about 300° to 450° Fahr. being
applied, solution will be found to be induced by the presence in the oil of the first
mentioned solution.
In place of a solution of gum damar being used as the inducing means to solution
of the resistent gum in the oil I may employ a small quantity of the liquid from
condensed vapour which is given off upon the treatment by fusion of gums as now
practised in order to fit them for varnish making and which liquid is now practically
a waste product as regards that manufacture.
Or, I may employ a small quantity of a solution of one class or description of
gum, in the manner described for damar as an agent for the reduction of a quantity
of another gum in a body of oil either with, or without, the addition of napthaline,
or like coal tar distillate solvent, suited to the purpose.
Dated the 23rd day of Anvil 1801

page_text: COMPLETE SPECIFICATION.
Improvements in the Treatment of Gums and the Preparation of
Varnishes therefrom.
I, GEORGE HAND SMITH of 71 Edith Road, West Kensington in the County
of Middlesex, Doctor of Medicine, 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 :-
This invention has for its object the treatment of gums in order to obtain varnishes
therefrom without employing fusion of those gums previous to their solution in the
solvent medium.
In the expression gums I include gums, gum resins, fossiliferous gums and
the like.
In carrying out my invention I design to utilize the property which I have
discovered by experiment-that gums of greater solubility, or more easily dissolved
gums, are in different, or relative, degrees available for use, as solvents or aids to
solution, or completer solution, of harder, or more refractory, gums; or one class of
gum is used as an aid in solution of another class or description of gum in the
presence of a suitable solvent medium-such as linseed or other oil-capable of
holding the gums, in solution or combination whilst conducting the operation at
low degrees of temperature, that is to say at temperatures sufficiently low, not to
cause injury to commercial value, or loss of weight to the gums to any serious extent
in the resultant production.
For instance this combination, or reduction of gums may be effected at as low a
temperature as (say) 250° Fahr. to commence with raising the temperature as the
operation proceeds.
As instance of soft gums, or resins, I may employ gum damar and ordinary
commercial resins of ready solubility.
As harder gums kauri, copal, anime, amber and other like gums or gum
resins.
In place of soft gums in solution as a reducing agent I sometimes employ a small
quantity of a distillate of any suitable gums and resins, produced by fusion by the
ordinary methods of varnish making.
As an example of my process I give the following: Supposing kauri gum to be
desired to be reduced to solution for use in making a varnish-a small quantity of
gum damar, so relatively insignificant in quantity as not to have any prejudicial
effect on the resultant varnish, is dissolved in, say, linseed oil. This solution is
then added in a suitable vessel to a quantity of kauri gum and thoroughly mixed
and the desired quantity of say linseed oil suitable for forming the solution of the
gum is added, and upon sufficient heat say about 300° to 450° Fahr. being applied,
solution will be found to be induced by the presence in the oil of the first mentioned
solution.
As an instance of proportions relatively of the foregoing matters I find that 1 lb.
of damar gum to 16 lbs. of kauri gum will give a good result with ordinary qualities
and the amount of oil used would be somewhat greater than in ordinary varnish
making the quantity being dependent on the quality of the result desired.
The soft gum may be added in the vessel containing the harder gums and a
small quantity of oil or solvent caused to combine with that soft gum therein and
as soon as that union is effected the soft gum solution upon the addition of the
solvent for the harder gums acts as an aid to its solution.
In place of the gum damar as the inducing means to solution of the resistant gum
in the oil I may employ a small quantity of the liquid products of distillation of
these gums and resins, such as is given off upon the treatment by fusion of gums in
ordinary processes of varnish making as now practised, and which liquid products
of distillation are now practically wasted.

page_text: The harder gums so fitted for solution are further or completely dissolved in oil
or other ordinary solvent.
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 In the manufacture of varnishes, the reduction of the relatively hard or
refractory gums or resins to a state fitting them for fuller solution by oil or ordinary
solvent by the aid of a small quantity of dissolved softer gum or resin (the softer
gum being dissolved either separately from or in the presence of the harder gum)
as set forth.
2: In the manufacture of varnishes effecting the solution at a low temperature
of varnish gums relatively hard and refractory to solution by the addition thereto
of a small quantity of the products of distillation of gums or resins admixed in a
body of suitable solvent as set forth.
Deted the 13th day of January 1892.
WM. BROOKES & SON,
55 & 56, Chancery Lane, London, Agents for the Applicant.