Substitutes for the Resins or Gums usually Employed in the Manufacture of Varnishes and Lacquers.
Year: 1886

page_text: Substitutes for the Resins or Gums usually Employed in the
Manufacture of Varnishes and Lacquers.
I, DR EUGEN SCHAAL of Feuerbach near Stuttgart in the Kingdom of Wur-
temberg, Chemist 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 resin-acids combine very readily both with the lower and the higher alcohols,
also with hydrocarbons, Phenoles, Naphtholes, and similar aromatic hydroxyl
derivatives, to form, with separation of water, ether-like compounds or true resin-
acid esters, baving the common property of non-solubility in carbonate of soda, in
contradistinction to the solubility of most natural resins in the same reagent. The
resin-acid esters are partly soft partly very hard resinous bodies which may be
used with greater advantage for the manufacture of varnishes than the natural
resins.
For the conversion into resin-acid esters may be used natural resin-acids as also
artificially produced resin-acids, and hitherto I have employed for this purpose the
resin-acids of Conifers, for instance, Colophonium Firwood resin &c, as also earth
resins, resins such as result from the oxidation of Petroleum and the hydrocarbons
from the distillation of coal, lignite, shale and peat.
As alcohols I have employed members of almost all the series: Methyl, Ethyl,
Lutyl, Amyl, Cetyl, Ceryl-alcohol and alcohol-like compounds from Petroleum, also,
single and multiple acid Phenoles, Naphtholes, Phenanthrole, Anthrole, Resorcine,
Glycerine, Hydrocarbons and Mannite and mixtures thereof.
For the production of resin-acid esters all methods may be employed with greater
or less success that are otherwise used for the production of esters; the most usual
methods are as follows:
a. The substances, mixed in the proportion of their equivalents, are heated
to a high temperature with or without pressure, and with or without addition of
substances such as acids, acid salts &c that take up water.

page_text: Example. 100 parts of Colophonium, Firwood resin &c are mixed with 17 parts
of Resorcine and are heated under a pressure of several atmospheres and at a
temperature of about 280° Cent, until the pressure perceptibly increases; the
steam produced is then allowed to escape and the heating and discharge of steam
is repeated until the formation of ester has been completed, which may be readily
ascertained by agitation of a solution thereof in Benzine or Ether together with
Soda.
In this way most of the resin-acid esters may be produced. If the alcohols &c
are not of a permanent nature, a correspondingly lower temperature must be
maintained.
b. The substances are heated while neutral gases are passed through for the
removal of the formed water, with or without the addition of water-absorbing
substances.
Example. 100 parts of resin-acids such for instance as Colophonium are heated
together with 44 parts of Naphthole to from 250° to 280° Cent and from time to
time a current of a neutral gas such as Carbonic acid is passed over the mixture in
order to remove the steam; and Naphthole that has passed off is made good. The
heating is continued until the ester is formed. This method is also pretty generally
applicable for all alcohols of a high boiling point.
c. The resin-acids are dissolved in an anhydrous alcohol or a mixture of resin-
acids and an alcohol or Phenole is dissolved in anhydrous Ethyl alcohol, and dry
hydrochloric acid is passed through, or the solution is boiled with sulphuric acid,
acid-salts, or other water absorbing substances.
Example. 100 parts of resin acids are dissolved in about 100 parts of anhydrous
Amyle Alcohol and from 40 to 50 parts of strong sulphuric acid are added; this is
boiled for a short time or dry hydrochloric acid is led into the alcohol solution and
this is allowed to stand. The formed esters soon separate out, and a further
quantity can be obtained from the supernatant lyes by distilling off the alcohol or
by mixing with water.
This method is applicable for all esters the components of which are soluble in
alcohol.
d. Mannite esters can be prepared in three different ways, but the method
employed by preference is to dissolve the Mannite in an equal quantity of Glycerine
or in sufficient glacial acetic acid, and then to treat it according to the process
described under (a).
Example. 100 parts of resin acids are mixed with a solution of five parts of
Mannite in five parts of glycerine or a solution of 10 parts of Mannite in about
20 parts of glacial acetic acid, and the mixture is then treated as at (a). Mixed
esters are produced by this means. In like manner sugar esters can be prepared.
The simple or mixed esters produced according to the one or the other method
are freed from foreign substances if necessary, by washing with water, carbonate
of Soda, &c, or by distillation, and they are then distilled in vacuo.
The liquid and soft distillates are first separated, after which come the solid
distillable esters, which serve as substitutes for mastic, Dammar, Sandarak &c
according to their origin and hardness. Those esters that remain in the still after
a temperature of from 300° to 320° has been reached are hard resins which replace
Copal and Amber.
The resin acid esters, like the natural resins, are applicable partly to fatty
varnishes, partly to turpentine, benzine and alcohol varnishes, and they may be
rendered more pliable by the addition of wax, linseed oil and the like.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is :-
"
1. The method substantially as herein described of preparing resin-acid esters
by first condensing the resin acids to esters by treatment with alcohols, phenoles,

page_text: and hydrocarbons under heating; with or without pressure and with or without
the addition of substances that facilitate the reaction, and then separating the
product by distillation into soft and hard resinous bodies.
2. An improved manufacture of varnishes or lacquers from resin acid esters,
consisting of a combination of resin-acid esters with volatile or fatty oils, hydro-
carbons or alcohols, substantially as herein described.
ABEL & IMRAY,
Agents for the Applicant.