The technique of etching

Aqua fortis is the name traditionally given to nitric acid, well known for its corrosive qualities.
Consequently the artistic prints produced using a metal plate engraved by means of an acid solution are known by the same name.

The aqua fortis production process begins with an initial series of operations performed on the metal printing plate; after this the plate is inked and a copperplate press is used to press the moistened sheet of paper against it to produce the etching.

The etching phase consists of the following procedures:

• The plate, normally made of copper, is spread with an even layer of waxy acidresistant paint.
• The design is then made using steel tipped instruments of varying gauges to remove the paint tracing the lines of the desired image.
• Once the design is complete, the “bite” is performed. The plate is immersed in a bath of acid. In the areas where the paint has been removed, the acid etches grooves in the underlying metal

To obtain different tones and nuances, or to highlight the various planes and depths of the design, different bile times are used; generally dark tones require a longer period of immersion in the acid. Once the last dip is complete, the paint is removed from the plate, which is thoroughly cleaned and prepared for printing.

Printing is performed with the help of a copperplate press. This is usually composed of a metal surface, which passes between two cylinders, which press down upon it, manoeuvred manually by special gears.

The printing phase consists of the following procedures:

• The first phase consists of spreading the ink evenly over the plate, so that it fully penetrates all the grooves. The excess ink then has to be removed so that the engraved lines emerge with completely clean profiles.
• The plate is then placed on the surface of the press with the design facing upwards; a sheet of paper, previously moistened to soften it, is then placed over the plate.
• The revolving cylinders of the press exert pressure on the plate and the paper, thus transferring the ink from the plate to the paper, these are then carefully separated, the paper being peeled off delicately, holding the edges.
• The inked paper must then be dried under pressure so that the sheet retains a smooth and even form.

In this way a limited number of prints can be made from the same plate, before the latter deteriorates and becomes unusable. All the prints made from the same plate are rigorously signed and numbered by the artist. Of the two numbers (1/100, 2/100 etc.), the first indicates the number of the individual print and the second the overall number of prints in the series   

L’Ippogrifo Stampe d’Arte produces and sells only and exclusively original graphic Pieces of art.

Each work sold it is accompained by its certificate of authenticity:

• It guarantees that the matrix was created by hand by the author who signs the pieces
• It guarantees that each piece was printed by hand by the author with the press machine.
• It guarantiees that each colouring was in watercolour.
• It guarantiees the progressive numbering which mark the limited run.

Every etching carries a dry mark depicting a Hippogriff