Improvements in the Method of and in Preparations for Protecting Gilt or Bright Metallic Surfaces.
Year: 1887

page_text: Improvements in the Method of and in Preparations for Protecting
Gilt or Bright Metallic Surfaces.
I SAMUEL CHALLONER of 21 Regent Road Salford, in the County of Lancaster,
Gilder and Picture Frame Manufacturer, do hereby declare the nature of this
Invention to be as follows:
My Invention relates to gilded articles and to articles coated with leaf metal or
with films of metal and generally to metal articles or to articles or objects having
metallic surfaces which it is desirable to protect from the deteriorating effects of the
atmosphere or of vapours or gases contained therein. In order to obtain such
protection I provide such articles with a coating or enamel which admits of being
washed and which whilst acting as a preservative adds to the lustre or appearance of
the object to which it is applied. To avoid repetition I will suppose the article to be
treated to be an ordinary gilt or so called gilt picture frame. The gilt surface of the
frame having been cleaned or prepared in the ordinary or in any suitable manner
receives a preliminary coating which serves as a substratum for the enamel coating
which will be subsequently applied. The liquid preparation used for this preliminary
coating contains gelatine or gelatine and a soluble alkaline silicate such as what is
sometimes termed water glass. I do not allow this coating to become quite hard
before applying the coating of enamel. In the preparation of the enamel I dissolve
pale African Copal in methylated alcohol of a suitable strength without previously
fusing the copal as is done when making varnishes, and powdered glass is then added
to the other ingredients. The solution is aided by agitation and when the solution is
completed and the glass has settled the clear solution is decanted. To this I add
alkaline silicate and if desirable colour the mixture to any required tint.
preparation is then applied to the article or object which has been coated as aforesaid
and has been dried until a brush charged with the enamel preparation will pass over
the surface freely without dragging or adhesion of the brush. The article or object
is then subjected to a suitable temperature in a stove in order to cause the enamel to
set hard and brilliant.
Dated this 4th day of February 1887
The
JULIUS ALLMANN & Co.,
70, Deansgate, Manchester,
Agents.

page_text: COMPLETE SPECIFICATION.
Improvements in the Method of and in Preparations for Protecting
Gilt or Bright Metallic Surfaces.
I SAMUEL CHALLONER of 21 Regent Road, Salford, in the County of Lancaster,
Gilder and Picture Frame Manufacturer 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 that is to say :-
My Invention relates to gilded articles and to articles coated with leaf metal or
with films of metal and generally to metal articles or to articles or objects having
metallic surfaces which it is desirable to protect from the deteriorating effects of the
atmosphere or of vapours or gases contained therein.
In order to obtain such protection I provide the surfaces which it is intended to
protect with a coating or enamel consisting of copal and a soluble alkaline silicate
such as what is sometimes termed water glass. This enamel admits of being washed
and while acting as a preservative to the surface below adds to the lustre or
appearance of the object to which it has been applied.
For the purposes of description I will suppose the article to be treated to be an
ordinary gilt or so called gilt picture frame. The gilt surface of the frame having
been cleaned or prepared by the ordinary or by any suitable method receives a
preliminary coating which serves as a substratum for the enamel coating which will
be subsequently described.
I prepare this substratum in the following manner :-In one kilogramme of water
I dissolve 4 grammes of gelatine and to this solution I add 1 Kilogramme of a
solution of water glass of the usual commercial strength say having a specific gravity
compared with water of 1.256.
The object of using gelatine in this solution is simply to enable the preliminary
coating to be applied more evenly than would be the case without it and in the case
of surfaces which are not repellant of an aqueous solution of water glass the gelatine
may be dispensed with.
I do not allow this preliminary coating or substratum to become quite dry before
the application of the enamel coating but only to such an extent as that a brush
charged with the enamel preparation will pass over the surface freely without
dragging or adhesion of the brush.
In the preparation of the second or what I term the enamel coating I make a
saturated solution of pale African copal in methylated alcohol of suitable strength
without previously fusing, pulverising or oxidising the copal and without subjecting
the vessel containing the methylated alcohol and copal to the action of heat. The
solution is however aided by agitation. To such a solution of copal I add very finely
powdered glass and after having shaken or otherwise agitated the mixture
allowed to stand until the coarser part of the glass powder has settled and the clear
1S

page_text: supernatant solution is then decanted. For some purposes the copal solution is
coloured by the addition of such colouring matters as may be soluble or can be held
in suspension in the solution.
If such a saturated solution of copal is found to give too thick a coating for the
particular article to which it is applied it may be diluted to any desirable extent by
the addition of methylated alcohol.
To the solution of copal prepared as above described I add varying proportions of
a solution of water glass diluted with hot water. The quantity of water glass to be
added varies according to the nature of the surface to be protected and the effect
which it is sought to obtain. Under some circumstances the water glass contained in
the substratum is sufficient and in such cases the copal solution is used without the
addition thereto of water glass.
The enamel preparation above described is applied in any convenient manner to
the surface which has already been coated with the substratum before mentioned
as for instance by means of a brush or by dipping the article into the enamel
preparation.
The article is then dried either in the open air or in a stove according to the degree
of brilliancy which it is desired to obtain.
In place of the application of waterglass and an alcoholic solution of copal
successively to the surface to be protected I in some cases use a single preparation
containing a solution of waterglass and an alcoholic solution of copal in combination
and which may be employed without any substratum. In the production of such
preparation 1 dilute or dissolve 1 kilogramme of water glass of the strength herein-
before mentioned in 2 kilogrammes of hot water and to each kilogramme of an
alcoholic solution of copal prepared as hereinbefore described I add 125 grammes of
this hot solution of waterglass. The mixture is then shaken or otherwise agitated so
as to produce an emulsion which is applied at once to the article the surface of which
it is desired to protect.
I do not confine myself to the exact proportions of ingredients mentioned but
may vary them according to the nature of the surface or article to be protected.
Having now particularly described and ascertained the nature of the said invention
and in what manner the same is to be performed I declare that what I claim is :—
(1.) The application of an alcoholic solution of copal in combination with a soluble
alkaline silicate to metallic surfaces or to the surfaces of metallic coatings for the
purpose set forth.
(2.) The successive application of preparations containing waterglass and an alcoholic
solution of copal substantially as and for the purpose set forth.
(3.) The preparation and application in the form of an emulsion of copal and
waterglass prepared and applied substantially as and for the purpose set forth.
Dated this 6th day of September 1887.
JULIUS ALLMANN & Co.,
70, Deansgate, Manchester,
Agents.