Restoration of the mural paintings of the IES Ramiro de Maeztu

The paintings are made with the tempera technique on a plaster support. The letters are made in gold glitter except the initial of each word that is tempera in red. 

These are four panels made on the longest walls of the Mathematics department, a large elongated room with large windows located on the short walls. All of them are framed with a plaster molding. Two of them, "Primitive Mathematical Culture up to the XNUMXth Century" and "XNUMXth Century Modern Period and Contemporary XNUMXth Century" are located on the wall of the access door that is inside, while the other two, "XNUMXth Century Ancient Greece Period and Rome VII Century» and «VII Century Medieval Period and Renaissance XVII Century» are on the contrary, which is exterior. This determines certain aspects of its state of conservation, those located on the outer wall, present a greater degree of dirt due to humidity and temperature changes to which they are exposed. 

Each panel covers a historical stage in mathematical discoveries and its discoverers that are titled thus: 

• PRIMITIVE MATHEMATICAL CULTURE BEFORE THE VI CENTURY
• VII CENTURY PERIOD ANCIENT GREECE AND ROME VII CENTURY
• VII CENTURY MEDIEVAL ERA AND RENAISSANCE XVII CENTURY
• XNUMXTH CENTURY MODERN AND CONTEMPORARY ERA XNUMXTH CENTURY

The date of execution of the paintings in the Mathematics classroom is the year 1946, all the panels are signed and dated by the author in the lower part, with dark earth-colored paint: "ANTONIO / COBOS / 46".

The author: 

Antonio Cobos (1908-2001), was born in Guadalajara into a wealthy family. In 1915 he moved to Madrid. He studied at the Jesuits where he began to excel in drawing. Later, while studying law, he will do his first jobs as an advertising cartoonist and book illustrator, work that he will continue after graduating. 

After the Civil War, he began to teach Art History classes at the Ramiro de Maeztu Institute, where he made a series of mural paintings in different rooms of the center: in the assembly hall, the chapel and, those that concern us, in the Department of Mathematics.

The paintings showed various damages such as generalized dirt due to dust and environmental pollution, small fissures in the walls, flaking of the pictorial layer with slight losses of polychrome, cracking in areas with greater filling and shine, as well as scratches and faults due to impacts on the upper part. bottom, accidentally produced by the daily use of the Mathematics room where they are located.

Before the restoration, stains, halos of dirt and oxidation of the golden letters on the cartouches were observed. The frames had small blows with losses and cracks in some areas and oxidation of some of the nails that anchor them to the wall.

The restoration work began with a previous detailed study of the state of conservation of the work, as well as consistency tests of the paintings and humidity measurements to verify that the walls were dry.

The interventions carried out have been carried out in the following steps:

• Cleaning:

Fundamentally dry and mechanically. after which a cleaning of the pollution and adhering dirt was carried out with sponges type Wishab. The fragile parts and those in poor condition are reserved for consolidation and fixation. The most encrusted dirt and stains due to inadequate cleaning, located mainly in the lower parts of the panels, were tried to be minimized as far as possible, with different soft erasers. 

• Temper Fixation:

Specifically, in the areas with crackles, before the polychromy was settled, it was determined that the paint had to be fixed and, after various tests, it was done by applying resin Paraloid B-72 in 3% toluene. This very low concentration allows the paint to be fixed without saturating it and thus not changing the appearance of the tempera, which is completely matte. In the rest of the surface this fixation was not necessary. 

• Consolidation and settlement of polychromy:

After various tests, it was determined that the best product for consolidation and punctual settlement in areas with lack of adhesion, cracking and flaking of the polychrome was the resin Acrylic 33 3% in distilled water. Due to the high porosity of the tempera, it had to be applied with great care so as not to saturate the paint and change its appearance. Controlled pressure was then applied with cotton moistened with acetone. Once the treated areas were dry, the surface remains of resin were removed with acetone to remove shine and saturation spots. 

• Filling of gaps. Coated:

The gaps in the panels, being very superficial, were filled with Modostuc. The cracks in the moldings of the plaster frames were filled with Standard waterplast. 

Both the application of plaster and stucco as well as the removal of stucco were carried out with great care so as not to invade the edges of the gaps since the fragility of the tempering makes the procedure difficult. 

The stripping was done with fine-grain sandpaper and the edges with a curved-blade scalpel, slightly moistening the burrs beforehand to level with the pictorial surface. The use of grazing light for this process is essential to leave the gaps as level as possible with the pictorial surface. 

• Chromatic reintegration:

The gaps and areas with wear were reintegrated with watercolors. Stains that could not be removed were reintegrated on top with soft, pastel, and watercolor pastel pencils. 

The outer frame has been glazed with acrylic paint similar in color to the original. Despite having been able to clean a lot, the lower areas presented dirt that was highly consolidated from previous cleanings with damp cloths. 

• Elimination of overpainting:

The overpainting of the panel «S. VI ancient Greece and Rome S.VII» was removed with acetone and controlled humidity, finishing mechanically removing it at the point of a scalpel. 

The reintegration has been done with acrylic colors, in a mimetic way.

With the treatments described, the restored wall paintings have recovered their original expressiveness.

^{Primitive Mathematical Culture Prior to SVI}

^{XNUMXth century Ancient Times, Greece and Rome XNUMXth century}

^{XNUMXth century Medieval Period and Renaissance XNUMXth century}

^{XNUMXth century Modern and Contemporary Period XNUMXth century}