Improvements in Vulcanized Kerite Compounds and in Processes for the Manufacture of the same.
Year: 1885

page_text: Improvements in Vulcanized Kerite Compounds and in Processes
for the Manufacture of the same.
"
I, HERBERT JOHN ALLISON, of the firm of Allison Brothers, of 52 Chancery
Lane, London, in the County of Middlesex, Patent Agents, do hereby declare
the nature of said invention for IMPROVEMENTS IN VULCANIZED KERITE
COMPOUNDS AND IN PROCESSES FOR THE MANUFACTURE OF THE SAME," (a com-
munication to me from abroad by Austin Goodyear Day, of the City and County
of New York, in the State of New York, and United States of America), and
in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement:-
Letters Patent of even date herewith have been granted for improvements mado
by the said Austin Goodyear Day in vulcanized kerite compounds, and the present
invention consists in the combination of certain vegetable astringents with the
cotton-seed oil and linseed-oil or their equivalents and the other ingredients which
compose the kerite, and the object of it is to impart to the latter an improved
fibrous character, thereby increasing its toughness and elasticity and enabling a
larger proportion of it to be employed whenever it is desired to be mixed with
india rubber, and also better adapting it for use in some cases as a substitute for
rubber.
The chief part of this new process is the same as that set forth in letters patent
number 36 of the year 1878 granted to the said Austin Goodyear Day in Great
Britain, and a portion of the description of the treatment therein directed to be
followed will suffice for this specification.
The essential ingredients in carrying out the present process are in addition to
the vegetable astringents, cotton-seed oil and linseed-oil or equivalent vegetable
oils, together with coal-tar, or bitumen, and sulphur in its ordinary form, or in
place of the latter the said Austin Goodyear Day may, in accordance with letters
patent of even date herewith, employ the sulphide of antimony or other suitable
sulphide, or both sulphur in its ordinary form and a sulphide combined; and the
Price 1

page_text: substance of the method by which he unites the said ingredients with each other
to make the kerite product, is, to first mix together and heat the cotton-seed oil
and coal-tar or bitumen or equivalent, and after they have properly combined to
add the linseed-oil to the heated mixture, and then introduce the astringent, and
afterwards put in the sulphur or sulphide or both combined, and increase the
temperature of the whole to such extent and for such length of time as will produce
vulcanization of the mass.
In putting this process into practice, the said Austin Goodyear Day first mixes
the cotton-seed oil and coal-tar or bitumen together in a suitable kettle or boiler,
under a suitable heat and for a sufficient length of time to cause them to unite
together freely and thoroughly. The temperature ordinarily required for this
purpose will be about 300° to 330° Fahrenheit, and the time generally from three
to five hours. The mixture is then cooled down to, say, from 200° to 220°, or
sometimes to only 240°, Fahrenheit or thereabouts, and then the linseed-oil may
be added.
To obtain the best result, however, the said Austin Goodyear Day lets the
cotton-seed oil and coal-tar or bitumen stand over night to cool. If this course be
adopted, they will be found in the morning to be thoroughly combined, and he then
heats them up to the above-specified temperature of from 200° to 220°, or some-
times 240°, Fahrenheit, and adds the requisite quantity of linseed-oil. When the
linseed-oil has become thoroughly incorporated with the other ingredients, which
usually takes from one to two hours, and preferably a little while before or at about
the time when he is ready to add the sulphur or sulphide, which he generally
commences to do when the mixture is at a temperature of say 230° Fahrenheit, he
introduces a small quantity of some suitable vegetable astringent such as tannin or
tannic acid, extract of gambia, extract of hemlock bark, extract of pine, spruce or
oak bark, extract of nut galls, sumac or the like, and then put in the sulphur
or sulphide, adding the latter gradually, and as it combines with the other
ingredients, he usually raises the temperature to about 275° to 300° Fahrenheit,
or in that vicinity, the degree of temperature depending largely upon the length of
heating-time employed.
The heating of the compound may be continued until vulcanization of the mass
takes place, say, in the case of a usual working batch of about one hundred pounds
for from five to ten hours, or sometimes longer.
When the vulcanization is complete the compound is finished, and it may then
be poured into moulds or pans of any desired dimensions, and allowed to cool for
use or for the market.
The said Austin Goodyear Day sometimes adds the astringents after the sulphur
or sulphide, and this may always be done if desired.
The proportions of all these ingredients may be greatly varied, but be recom-
mends, as adapted to produce a compound suitable for most ordinary purposes,
twenty-seven pounds of cotton-seed oil mixed with say twenty pounds of coal-tar,
or fifteen to twenty-five pounds of bitumen, to which may be added twenty-seven
pounds of linseed-oil, one-half pound tannin or tannic acid, and from twelve to
sixteen pounds or thereabouts of sulphur, or if a sulphide is employed, say the
sulphide of antimony or sulphide of zinc, from six to eight pounds or thereabouts
of sulphur in the ordinary form and about the same quantity of the sulphide..
The proportions which are preferred of the vegetable astringents other than
tannic acid which are named above, are as follows:-
Extract hemlock bark, about pound;
Extract pine bark, about
pound;
Extract spruce bark, about pound;
Extract oak bark, about pound;
Extract nut galls, about pound;
Extract gambia, six to eight ounces;
Et

page_text: The said Austin Goodyear Day does not confine himself to the astringents named
in this specification, as there are others which may be used. Tannic acid is the
active principle of all or most of the vegetable astringents, and any of them which
contain a sufficient amount of it will answer a good purpose.
The effect of these new ingredients is to give the product a better fibrous
character than has been ever before obtained, and it will be obvious that the
greater the extent to which the crude kerite can be caused to possess this property,
the greater will be its value for all purposes in the arts. Especially for such uses
as mixing it with india rubber in order to cheapen the cost of the raw material, or
in some cases substituting it for india rubber, the increased cohesiveness and the
superior elasticity which the astringents impart to it will be found of much
importance. The astringents also improve the capacity of the crude kerite to
combine with india rubber, and render the product more solid and durable.
In practice, whenever desired, gum camphor, as well as sulphuric, nitric or
muriatic acid, or oxide of iron, may be added to the present compound in the same
manner as described in the said 1878 patent, but the proportions in which they are
used should preferably be considerably larger than there specified.
In addition to employing vegetable astringents with the oils in combination with
coal-tar or bitumen and with or without sulphur, the said Austin Goodyear Day
believes he is the first to combine them with vegetable oils without the other
ingredients, as a step in the manufacture of rubber substitutes and analogous
compounds. For such purposes, his experience has shown him that so used alone
they have a decided value.
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
First. The herein described process of manufacturing crude kerite compounds,
consisting of combining one or more vegetable astringents with vegetable oils, coal-
tar or bitumen, and sulphur or a sulphide or both the latter together, substantially
in the manner set forth.
Second. The combination of one or more vegetable astringents with vegetable
oils, and subjecting them, without the admixture of coal-tar or bitumen, and either
with or without sulphur or a sulphide or both the latter together to the treatment
herein described for the purpose specified.
Third. The within described new product consisting of a crude kerite compound
formed by the mixture of vegetable astringents with cotton-seed oil, linseed-oil, and
coal-tar or bitumen, substantially as set forth.