PROCESS FOR PRODUCTION OF THE ACID ETHERS OF RESINOUS GUMS, SUCH AS COPAL AND THE LIKE
Year: 1884

page_text: I, JOHN IMRAY of No. 28 Southampton Buildings, Chancery Lane, in the
county of Middlesex, Consulting Engineer and Patent Agent do hereby declare
the nature of my said invention for "PROCESS FOR PRODUCTION OF THE ACID
ETHERS OF RESINOUS GUMS, SUCH AS COPAL AND THE LIKE" to be as follows:-
The resin acids freely combine with the lower and higher alcohols, hydrocarbons,
phenols, naphthols and similar aromatic hydroxylic derivatives by separation of
water to form compounds analogous in constitution to ethers or genuine resin-
acid-ethers, which have the common property of being insoluble in soda thus
differing from most of the natural gum resins, which are soluble in soda.
The resin-acid-ethers are partly soft and partly very hard resinous bodies, which
can be advantageously employed as the natural resins for varnishing and such like
purposes. For conversion into resin-acid-ethers are suited not only the natural
resin acids but also those artificially extracted from the gum resins which have.
been freed from their softer portions. This separation of volatile ingredients not of
the resin-acid class can be effected,
1, By distilling in vacuo at 300° to 350° C, or by superheated steam or neutrál
gas.
2. By extracting the mixture of resin acid and neutral ingredients by solvents
such as dilute spirits of wine.
Thus are converted into resin acid ethers, the resins of conifers such as colophon
and bitumens, as by the oxidation of the petroleum and hydrocarbon, they resulted
from distillation of coal, shale, peat and the like.
Almost all classes of alcohols were employed including the methyl, ethyl, butyl,
cetyl and ceryl alcohols, and alcoholic substances from petroleum, and the simple
or multiple acid phenols, naphthols, phenanthrols, anthrols, glycerine, hydrocarbons,
mannite.
The resin-acid-ethers result from their compounds :—
(a) by heating to high temperature the materials mixed in the proportions of
their equivalents with or without pressure, and with or without addition of
substances. absorbent of water such as acids or acid salts ;-
(b) by heating by means of neutral gases so as to drive off the water that is
formed;-
(c) by heating the metallic salts of the resin acids with the haloid or sulpho-
combinations of the phenols and their homologues.

page_text: The production of resin-acid-ether is advantageously effected from resin acids
and hydrocarbons with addition of glacial acetic acid or glycerine, mixed ethers
being the final product of the reaction. When these are formed, the superfluous
alcohol &c, are then removed by treatment with water or distillation &c. The
residoal mass is then by distilling in vacuo at 240° to 350° C., separated into a
more volatile ether, which can take the place of mastic, dammara or sandarac, and
a very hard ether, which can be used instead of copal and amber.
Example. By distilling colophon in vacuo to 350° C, the volatile ingredients are
driven off and the hard resin-acid residue, being weighed, has added to it 10 per
cent of anhydrous glycerine. The mixture is heated with agitation and under a
pressure of several atmospheres to 250° C. After some time the pressure is raised by
farmation of water vapor and evolution of neutral gases which are allowed to
escape. When the separation of water is complete, the operation is stopped, the
raw resin-acid-ether being then distilled by which it is separated into the softer
and the very hard resins.
The treatment of other materials can be readily understood from the above
example, it being suited to their peculiar properties without altering the general
character of the process.
Like the natural guin resins, the resin-acid-ethers are convertible partly into fats
and partly into turpentine, benzene and spirit varnishes, and, when required, may
be rendered more plastic by admixture of wax, paraffin, palmitone and other similar
substances.
COMPLETE SPECIFICATION.
I, JOHN IMRAY of No 28 Southampton Buildings, Chancery Lane in the
County of Middlesex, Consulting Engineer and Patent Agent do hereby declare
the nature of my invention for "PROCESS FOR THE PRODUCTION OF THE ACID
ETHERS OF RESINOUS GUMS, SUCH AS COPAL AND THE LIKE" and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement:--
The rosin acids freely combine with the lower and higher alcohols as also with
bydrocarbons, phenols, naphthols, and similar aromatic hydroxyle derivatives by
separation of water, to form ether-like compounds or genuine resin acid esters,
which possess the common property of not dissolving in soda, in contradistinction
to the solubility of most natural resins in this substance.

page_text: The resin acid esters are partly soft partly very hard resinous bodies, which may
be applied with more advantage than the natural resins to the preparation of lacs
and varnishes. For conversion into resin acid esters, are suited, both ready prepared
resin acids as also artificial acids prepared from resins, which have been separated
from softer components. This removal of volatile bodies, not belonging to the class
of hard resins, can be effected, firstly by distilling in vacuuo at from 300° to
350° Cent, by distilling with superheated steam or in a current of neutral gases;
secondly also by extraction of the mixtures of the resin acids and neutral bodies by
solvents such as dilute alcohol
Hitherto the resins of conifers (colophonium), also earth resins, resins such as
are obtained by oxidation of petroleum and hydrocarbons, from the distillation of
lignite and coal, shale and peat, 'have been employed by my correspondent for the
formation of esters.
For alcohols have been employed members of almost all groups, ethyl, butyl,
cetyl, ceryl,-alcohols, and-bodies aimilar to alcohols from petroleum, also 'mono- or
multiple acid phenoles, naphtoles, phenanthol, anthrole, glycerine, hydrocarbons
and mannite. For the production of resin acids esters may be employed with more
or less success all methods that are employed for the production of esters.
The most suitable modes of operating are as follows:-
a. Heating the bodies, mixed in the proportion of their equivalents, to high
temperatures, with or without pressure, and with or without addition of dehydrating
substances, such as acids, acid salts, &c.
Example. Colophonium is distilled in vacuo at 350° Cent. to remove the volatile
constituents and the residue, consisting mainly of solid resin acids, is mixed with
17 per cent of resorcin and heated under a pressure of several atmospheres and at
a temperature of about 280° Cent, until the pressure increases perceptibly; the
steam is then allowed to escape and the heating and discharge of steam are
repeated until the formation of ester has been completed, this being at once
indicated by shaking up a solution in benzine or ether with soda.
In this way most resin acids esters may be obtained. If the alcohols are not
permanent, a corresponding lower temperature must be employed.
b. Heating combined with passing neutral gases through the mass in order to
remove the water with or without the addition of dehydrating substances.
Example.. 100 parts distilled colophonium (as in a) are treated with 44 parts of
naphthol to from 250° to 280° Cent, and periodically a current of neutral gas, for
example, carbonic acid, is led over it in order to remove the steam, any naphthol
that may be carried off is replaced. The beating is continued until the ether is
formed.
This method also is pretty generally applicable for alcohols &c of higher boiling
point.
c. A mixture is dissolved in absolute alcohol, and dry hydrochloric acid is
introduced, or the solution is boiled with sulphuric acid, acid salts and other
dehydrating substances.
Example. 100 parts of solid petroleum acid, such as is obtained in the oxidation
of petroleum and other similar bydrocarbons, are dissolved in about 200 parts of
absolute alcohol, and from 40 to 50 parts of strong sulphuric acid are added, and
the mixture boiled for some hours, or dry hydrochloric acid is let into the alcoholic
solution until saturation, and the mixture is allowed to stand.
The greater part of the ester formed will then soon separate and the alcohols of
the supernatant liquid being distilled off or the latter being mixed with water, a
further quantity of ester is obtained.
This method is applicable for all esters the components of which are soluble in
alcohol.
d. Mannite ester can be prepared according to either of the above described
methods, but it is advisable to dissolve the manite in equal quantities of glycerine
or in sufficient glacial acetic acid and then to treat it according to "a"

page_text: Example. To 100 parts of distilled colophonium are added 5 parts of mannite
dissolved in 5 parts of glycerine or a solution of 10 parts of mannite in about
20 parts of glacial acetic acid, and the compound is treated, as at “a.” Mixed
esters are produced by this means. In a similar manner sugar esters are
prepared.
:
The resin acid esters prepared by the one or the other of the above described
methods, are when necessary freed from foreign impurities, either by washing with
water, Boda &c or by distillation and are then distilled off in vacuuo.
The constituents passing away at from 240° to 350° Cent, are collected separately,
these are the colorless softer asters, such as serve as substitutes for mastic, dammar
sandrake &c, the remaining esters are hard resins that serve as substitute for copal
and amber.
The resin acid esters, similarly to the natural resins, are partly applicable to fatty
lacs, and varnishes and partly to turpentine oil, benzine, and alhbolic lacs and
varnishes, and when necessary they are rendered more plastic by the additions of
wax, paraffin, palmiton (C 81 H 62 O) linseed oil and similar bodies.
The boiling of the resin acid esters with linseed oil at about 300° Cont can be
effected with advantage in closed vessels with the addition of a percentage of a
hyperoxide, for instance, of lead or of barium hyperoxide, instead of in open
vessels a current of a neutral gaa, for instance, carbonic acid being led through.
By this means varnishes of lighter color are obtained.
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 method of preparing resin acid esters by freeing raw resin acids in the
first instance from volatile or soft constituents, by distillation or extraction, the
hard resin acid residues being then condensed to esters by treatment with alcohola
or phenole in the presence of heat, with or without pressure, and with or without
addition of substances favoring the reaction, and lastly by separating the resin acid
esters into softer and harder resin like bodies by distilling them ip vacuo.
2. The method. substantially as herein described of preparing varuishes from
resin acid esters, by treating them with volatile or fatty oils, with hydrocarbons or
with alcohols in a similar manner to natural resins.