IMPROVEMENTS RELATING TO THE PREPARATION OF LITHOGRAPHIC PRINTING SURFACES
Year: 1884

page_text: I HENRY HARRIS LAKE, of the firm of Haseltine, Lake & Co, Patent Agents,
Southampton Buildings, in the County of Middlesex-do hereby declare the
nature of my invention for "IMPROVEMENTS RELATING TO THE PREPARATION OF
LITHOGRAPHIC PRINTING SURFACES" to be as follows:-
This invention relates to an improved method of preparing lithographic printing
surfaces.
There are in lithography the following distinct methods of preparation.
1st by engraving 2nd by transferring in which the drawing or writing appears
elevated on the stone 3rd by drawing or writing is directly drawn upon the stone
4th by drawing with a crayon on a grained stone 5th by transferring from a
granulated paper upon stone and 6th by etching in the stone In all the preceding
methods with the exception of the engraving the drawing or other design was
etched directly upon the stone by means of nitric acid or phosphoric acid, or the
like, mixed with gum and water in order to obtain impressions from the same.
The engraving, on the other hand was rubbed with linseed-oil in order to cause
the adhesion of the fatty printing ink.
According to this invention the drawing writing or other design produced upon
the stone by any of the methods hitherto employed and having been covered with
printing ink is gently rubbed with very fine colophony by means of cotton.
As soon as the colophony has combined with the printing-ink, the drawing,
writing, or other design is caused to melt lightly by applying an open flame to it.
The stone is then left to cool, it being subsequently brushed over with strong
caustic gum (generally composed of 1 part of nitric acid, 10 parts of dissolved
gum of the usual strength, and 20 parts of water, the solution being stronger or
weaker as required) until, the design has acquired the desired height.
This very simple process produces a much better effect, as regards beauty and
durability of the design, than heretofore.
The impression may be produced on dry paper even if the latter is not smooth
and as many as 100,000 reproductions may be taken without the design losing in
beauty or distinctness but on the contrary, increasing in this respect.
Dated this 11th day of Inl. 1884
HASELTINE, LAKE & Co.,
For the Applicant.

page_text: COMPLETE SPECIFICATION.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake, & Co, Patent Agents,
Southampton Buildings, in the County of Middlesex, do hereby declare the
nature of my invention for "IMPROVEMENTS RELATING TO THE PREPARATION OF
LITHOGRAPHIC PRINTING SURFACES and in what manner the same is to be
performed, to be particularly described and ascertained in and by the following
statement:-
"
This invention relates to an improved method of preparing lithographic printing
surfaces.
By the term lithographic surface I denote any surface to which the materials
used in lithography are applicable for the purpose of my invention.
There are in lithography the following distinct methods of preparation, viz :-
1st Engraving. 2nd Transferring, in which the drawing or writing. appears in
relief upon the stone. 3rd Drawing or writing directly upon the stone. 4th Drawing
with a crayon on a grained stone. 5th Transferring from a granulated paper onto
stone. 6th Etching the stone.
In all the preceding methods, with the exception of the engraving, the drawing
or other design is produced directly upon the stone by etching, by means of nitric
acid or phosphoric acid, or the like, mixed with gum and water, in order to enable
impressions to be obtained from the said stone.
In the case of engraving, the design is rubbed with linseed-oil, in order to cause
the adhesion of the fatty printing-ink.
In carrying the present invention, into practice, the drawing, writing or other
design is produced upon the printing surface by any of the methods hitherto
employed, the printing-ink is then applied thereto and is gently rubbed with very
fine colophony by means of cotton or other suitable material.
As soon as the colophony has combined with the printing-ink, the drawing,
writing or other design is dusted with powdered gypsum or other suitable material.
I then apply an open flame to the printing surface to burn, melt or fuse the
colophony, the printing ink and the gypsum or other material and thus cause these
substances to amalgamate and produce an enamelled design in relief upon the said
surface. In the case of a stone surface, these materials will also amalgamate with
the chalk or lime of the stone. The printing surface is then left to cool, and is
subsequently brushed over with a strong caustic solution of gum (composed, for
example, of nitric acid, sulphuric acid and phosphoric acid, or other acids and
dissolved gum) the solution being stronger or weaker as required.
This solution serves to clean the printing surface and remove any undesirable or
unnecessary products that may be formed in the process of burning.
This very simple process produces a much better effect as regards beauty
and durability of the design than has ever been obtained by the most skilful
artists.
The impression may be produced on dry paper even if the latter is not smooth,
and as many as 100,000 impressions may be taken from the design without its
losing in beauty or distinctness, but on the contrary gaining advantages in this
respect.

page_text: Lithographic stones treated by this process may be used on an ordinary printing
machine; the use of stones in this manner has hitherto been impracticable.
In conclusion the defects which so frequently occur in lithographic processes are
without exception successfully removed with this process.
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
In the preparation of printing surfaces on which designs have been produced in
the ordinary manner, the above described process which consists in applying to the
said designs printing ink, colophony and gypsum or other suitable material and
amalgamating these materials by melting or fusing the same by means of an open
flame to form enamelled designs in relief, as above specified.
HASELTINE, LAKE & Co.,
For the Applicant.