Improvements in and relating to the Production of Iridescent Surfaced Articles.
Year: 1892

page_text: te of Application. 26th Jan., 1892-Accepted, 27th Feb., 1892
COMPLETE SPECIFICATION.
[Communicated from abroad by JOHN JACOBSON, of Boston, County of Suffolk,
Massachusetts, United States of America, Artist.]
Improvements in and relating to the Production of Iridescent
Surfaced Articles.
I, HENRY HARRIS LAKE, of the firm of Haseltine Lake & Co., Patent Agents
45 Southampton Buildings, in the County of Middlesex, 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 object of this invention is to produce articles having an iridescent surface
adapted for use as buttons jewels or for other articles which may be made more
ornamental by having a surface that is iridescent or capable of decomposing the
light reflected from them.
It is well known that the iridescence or decomposition of light produced by
mother of pearl, for example, is caused by minute striations or numerous minute
parallel lines or ridges which naturally exist on the surface, and a similar decom-
position of light is produced by an artificially prepared optical surface sometimes
called a grating which is made by engraving numerous fine parallel lines upon a
suitable surface.
Such lines have to be carefully made and the optical gratings which have been
heretofore used for producing this phenomenon of dispersion or decomposition of
light have been very expensive, it being necessary to rule or engrave each surface
with great care by special appliances.
The present invention is based on the discovery that an engraved grating can be
employed as a die or form from which surfaces having the same optical effect can
be produced directly at very moderate expense, and without injury to the original
form which may thus be used to produce an indefinite number of articles having the
desired iridescent surface.
The specific manner of obtaining the desired surface from the engraved die,
depends largely on the nature of the article to which the surface is to be applied.
When the said article is composed of plastic material or material that is plastic
in some stages of its manufacture, as for example hard rubber, or celluloid, it may
be caused to receive the striated light dispersing surface by being pressed against
the surface of the die, or such striations may be produced upon a metallic surface
by stamping the metal with the die so as to impress the grooves or ridges in the
surface of the piece of metal that is stamped.
The specific mode which has been followed for producing buttons or similar
articles which may be used as a substitute of mother of pearl, although giving a
more brilliant iridescence is illustrated in the accompanying drawings in which:
Figure 1 is a plan view of an optical grating having a conventional representation
of its ruled surface.
Figure 2 is a longitudinal sectional view of a portion thereof, representing the
surface of the grating greatly magnified and also illustrating the formation of a
grating from the original ruled grating as a form or die.
Figure 3 is a perspective view illustrating a modified form of die.
Figure 4 is a face view, of a jewel or article composed of transparent material
having its surface striated in accordance with this invention.
Figure 5 is a sectional view of the dies employed in making such jewel, and
Figure 6 is a side elevation of a die which may be employed in producing the
dies shown in Figure 5.
In producing gratings or other articles having the same light effecting surface,

page_text: in accordance with this invention, an optical grating a Figure 1, is produced in the
usual manner by having its surface ruled or engraved with fine parallel lines
sufficiently closely ruled to produce the desired color decomposition of light.
In order to produce a similar light dispersing surface see Figure 2, on any
piece of material or article c that it is desired to have iridescent, the said article c is
pressed firmly against the striated surface of the grating a or the said grating is
stamped or pressed against the article e so that the surface of the latter is provided
with ridges and grooves or lines which are a counterpart of those on the grating a
and consequently have the same effect in decomposing the color that falls upon
the said surface b when the article is removed from the die, or in other words in
giving the said article c a striated or iridescent surface.
When the said article c is of soft metal it can be caused to receive the iridescent
surface by direct pressure of the surface of the die, and when the article is of
plastic material, such for example as celluloid or hard rubber, the striations may be
impressed in its surface from the striated surface of the die a when the said material
is in plastic condition or if the article has been previously hardened it may
generally be made sufficiently plastic to receive the striations from the surface of
the die by having the die somewhat warm when the material is pressed against it.
In some cases it may be necessary to apply pressure of greater intensity than can
be readily produced when the entire surface is acted upon at once, as is the case
when a die or grating of the form shown in Figure 1 is employed.
In such cases the dic may be of the form shown in Figure 3 in which the
striations are produced upon the curved or cylindrical surface which is applied to
the article that is to receive the corresponding surface with a rolling action so that
only comparatively small portions of the surface are acted upon at each moment
and greater intensity of pressure along the line of contact is afforded than when
the entire surface is acted upon at once.
In some cases the striated surface may be transferred directly to the surface of a
transparent material in which case the striations will disperse the light transmitted
through the article causing the dispersion of the transmitted light, as well as of the
light that is reflected from such surfaces.
For example, the brilliancy of jewels composed of glass, paste, or like material
having facets corresponding to those of a cut gem may be greatly increased by
providing the said facets or portions thereof with minute striations as indicated in
Figure 2, where the striations are greatly magnified in order to more clearly show
the same.
In practice the striations or lines formed on the facets of the gem should be at
least three thousand to the inch, and preferably more than ten thousand, and there
may be two or more sets of striations on each facet the lines of one set being all
parallel and equally distant, while those of the different sets may be at any desired
angle to one another.
A jewel having a striated surface of this kind may be produced by moulding the
glass or paste in dies of the form shown in Figure 5, which are properly shaped to
give the faceted shape to the jewel and have their facet producing surface provided
with the striations which may be ruled or engraved directly thereon or may be
produced by an impression from a properly prepared die such as represented in
Figure 6, on which the lines will have to be produced by ruling or engraving.
Having now particularly described and ascertained the nature of-this inven-
tion and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :-
1st. The herein before described improvement in the method of producing articles
having a striated light dispersing surface, which consists in forming the said surface
on the article by an impression from the surface of a form or die having a ruled or
engraved striated light dispersing surface, substantially as described.
Second. The herein described jewel or body of light transmitting material 'having

page_text: its surface made up of facets some or all of which are provided with striations,
substantially as and for the purpose described.
Dated this 26th day of January 1892.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.