Improvements in the Manufacture of Artificial Asphalt.
Year: 1889

page_text: COMPLETE SPECIFICATION.
Improvements in the Manufacture of Artificial Asphalt.
I, JACOB ERSLEV, of No. 11, Compagniestraede, Copenhagen, in the Kingdom of
Denmark, Merchant, 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 :-
Many attempts have been made to produce artificial asphalt, so as to be cheaper and
better than natural asphalt but up to the present time no one has been able to over-
come the difficulties connected therewith.
Artificial asphalt, as is well known, cannot, as heretofore made, withstand great
differences in temperature, for example, under the action of the sun it becomes soft
and even liquid, while under the influence of cold it becomes brittle and cracks. For
this reason it can only be used for floorings in places which are not submitted to
extremes of temperature but it cannot be used in the open air for pavements, streets
or roads, only natural asphalt being capable of standing the wear and weather; the
use of this latter, however, is somewhat restricted, in consequence of its relatively
high price.
From a hygienic point of view asphalt paving is an absolute protection as it is not
liable to harbour or develop Bacilli which are the cause of many epidemic diseases
and on this account alone it would be a great advantage if asphalt could be used
instead of ordinary paving, but natural asphalt is, as already stated, so costly that
it cannot be employed in all cases. After numerous experiments I have succeeded in
producing an artificial asphalt which possesses all the good qualities of natural asphalt
without its defects.
According to my invention I prepare artificial asphalt in the following manner :-
In a suitable metal pot I melt a mixture of coal-tar (pyroleum lithanthracis) and
resin (resina pini flava) in about the following proportions, viz. :-
80 to 90 parts of resin to 20 to 10 parts of coal-tar. After the mass is thoroughly
melted mix therewith 100 parts of pulverized sand or silicious earth or ordinary
dry clay (argillaceous earth) or any other suitable finely sifted earth or chalk in a
completely pulverized form together with 200 to 400 parts of rough gravel. After
the whole mass is melted together it is for ned into blocks in a mould so as to
facilitate transport. The asphalt thus prepared is employed in the same way as natural
asphalt.
It will be found to be absolutely proof against all temperatures as well as against
blows. It will not yield under a heavy pressure or load and it will not crack under a
powerful blow, it will not be effected by hot water and can be exposed to steam
without effecting any change in its condition.
Moreover my artificial asphalt makes better connection with the bed underneath it
than natural asphalt and thus prevents damp and water from lodging between the
asphalt and the bed; the said connection is nevertheless not strong enough to prevent
the asphalt from being broken up without destroying the bed. It will withstand the
action of acids and will wear longer than natural asphalt.
It is therefore evident that it is in every respect superior, as regards quality, to
natural asphalt; it is besides much cheaper than any known paving material and is
only half the price of natural asphalt.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed 1 declare that what I
claim is
A1
fan-s
Boxing
streets
roads and other places.

page_text: manufactured by melting together resin (resina pini flava) and coal-tar (pyroleum
lithanthracis) with an addition of pulverized sand or earth in a pulverized condition
such as finely sifted clay or chalk in about the proportions named.
Dated the 5th day of October 1889.
G. F. REDFERN & Co..
4, South Street, Finsbury, London, Agents for the Applicant,