Presentation on theme: "LINEA GRAFFI’ v5.1. Antigraffiti protection Antigraffiti protection Diagnostics preparation of intervention preparation of intervention In most cases."— Presentation transcript:
Antigraffiti protection Antigraffiti protection Diagnostics preparation of intervention preparation of intervention In most cases the damage is done on unprotected surfaces. Graffiti problem is faced by means of empirical methods and unsuitable techniques. The proper solution must come from a series of steps which will give the antigraffiti system. Cleaning graffitis Cleaning graffitis From protected surfaces Schema generale Anti-graffiti Treatment Removal of graffitis Removal of graffitis Identification of graffiti Characteristics of materials Operative tests Site logistics Physical-mechanical methods Sandblasting, pressure washing, waterjet sandblsting, low-pressure centrifuge washing, laser, etc. Chemical methods Solvents, paints removers, poultices, cleaners
The identification of graffiti to be removed is the complement to the most efficient removal methos: this can be determined with preliminary testing. The features of the material (stone, marble, bricks, plaster, wallpaints, etc) are critical at the same way: - physical properties of the surface (roughness, porosity) - resistance to washing (water absorption, sensitivity to alkaline/acid detergents, sensitivity to solvents) - mechanical properties (hardness, resistance to high-pressure waterjet) These features must be related to the state of conservation and to the possible artistic relevance: this will affect the operative logistics and the choice of cleaning technique and of protection needed. diagnosticaDiagnostics
Interventi Antigraffiti: Proposte e progressi sulla ripulitura e protezione delle superfici. Il punto della situazione sulla ricerca e sulle tecniche antigraffiti. A.Granato et al., GEAL srl, Incontri Tecnici Restauro 1999 e 2000, Ferrara – in collaborazione con CNR Firenze e Syremont spa Protezione Antigraffiti, studio preliminare. S.Galbiati e C.Garavelli, Politecnico di Milano, Incontri Tecnici Restauro 2001, Ferrara – in collaborazione con Geal srl e Istituto Centrale di Restauro, Roma Protezione Antigraffito, una ricerca sperimentale. S.Galbiati e C.Garavelli, Recupero e Conservazione, 2001, n.40-41 diagnostica Literature * *Issues are in Italian language
Materials and surfaces Porous and absorbing stone Cleaning volcanic tuffstone, extremely absorbing, can result very difficult. Cleaning unprotected surfaced could be almost impossible without causing damage to the stone. It is always needed to clean perfectly the surface before applying antigraffiti protection. Photo: wall covering made of Vicenza Stone (calcareous sandstone) with topical deposits of dark mildew. TECHNICAL REMARK Travertine is not an absorbing stone, but natural cavities present on unfilled surfaces will make extremely hard its cleaning. In some particular cases it is not possible to wash intensively with waterjet, like here in the historic centre of Florence, Italy. The stone is teh traditional Pietraforte sandstone in a façade of a 16th century florentine palace. Heavy encrustations of altered material and urban pollution deposits can be easily removed by an extracting poultice. Left: result after one application only.
Materials and surfaces Mixed materials Up and left: 2 very common cases of graffitis overlapping and/or drawn on different materials (bricks, concrete, painted metal, glass). Correct management of the working site must foresee preliminary tests to determine products and cleaning steps. Down: glass-tessera mosaic. Cleaning of tesseras is generally very simple, but could be difficult to clean light-coloured grouts without damaging.
Materials and surfaces Plaster and concrete Cleaning graffitis could result the most expensive intervention in terms of manpower, equipment, products. It is absolutely needed to carry out prelimary tests in order to determine the practical effectiveness and costs. In many cases re-making plaster is the most acceptable economic solution, when the antigraffiti protection was not made before. Up: uncontrolled use of aggressive detergents can make it worse, with colour casting and absorption of dissolved paints. Down: damage caused by a normal high-pressure washer on a traditional plaster surface
solvents : liquid and gel detergents and bleaches Sandblasting,sabbiatura, idrolavaggio, idrosabbiatura, etc. laser : its use is limited to some artwork only CHEMICAL METHODS MECHANICAL METHODS MIXED METHODS Removal of graffitis must be carried out by non-hazardous products and techniques to the operators and environment, neither destructive for the material Packs with absorbant poultices made with a substratum (natural clay, paper pulp, etc.) + detergent Various techniques : e.g. detergent + pressure washer Removal Low-pressure centrifuge washing
Low-impact mechanical methods Traditional pressure washing machines and sandblasters can provoke irreversible mechanical damage to the surfaces, caused by direct impact of abrasive with high pressure. Present trend is to subsitute traditional abrasives with those of low hardness and utilize equipments which generate variable helical-shaped jet, in order to get minimum pressure tangent to the surface and thus obtaining a controlled action. This market is expandind by reducing the costs of equipmet and of site management. Damages caused by high-pressure sandblaster on a sandstone wall cladding
Chemical cleaning methodologies When tested to be effective, the chemical cleaning is the best method to avoid damages to the surfaces. Of course it should be recommended to respect operation sequence and products determined by prelimary testing. In the pictures 2 examples of intervention with liquid deter-solvents. In some particular cases and on porous materials it is advised to use chemical extracters with absorbing power, in order not to diffuse the dissolved colour into the material. Generally the use of extracters (poultices based on natural clay) is alternated with liquid detergents.
Technical features Avoids grip of graffitis Discouraging effect Reversibility Not filming Easy and unexpensive maintenance saves the permeability to water vapour (breathing) of the protective treatment, can be used on monuments and artworks does not produce chromatic alteration after its application and after long exposure makes the adhesion of colours and paints difficult ANTIGRAFFITI PROTECTION Products are not hazardous No visual impact many competitors’ products are classified toxic or noxious, or use solvents with heavy environmental impact makes cleaning faster and easier the removal of graffiti can be carried out with fast non-hazardous cleaners Versatility 2 products only to protect all materials
Practical examples of application ANTIGRAFFITI PROTECTION No sophisticated tool is required for the application of GEAL’s antigraffiti protectives
ANTIGRAFFITI TREATMENT Before A step of removal with GRAFFÍ ESTRATTORE Piazza Mercadante Naples, Italy End of the work, after cleaning and protection with GRAFFÍ SCUDO Statue and basement made of white Carrara marble Examples of intervention
A step of cleaning with GRAFFÍ TERGENT Surface had been protected with GRAFFÍ DEFEND Covering of a façade made of Pietra Serena sandstone ANTIGRAFFITI TREATMENT Examples of intervention
Underpass Fortezza da Basso, Florence, Italy – opened to traffic in september, 2004 Wall covering of a tunnel made of Santafiora sandstone Santafiora is a siliceous sandstione, coarse, rich in fossils and imprints of mud- eaters, with medium-high absorption Some prelimary tests were carried out, in order to determine dosages and products to be applied. Accepted working proposal involved a preliminary washing with SERVICE ACIDO diluted, a protective impregnation with GRAFFÍ FOND, and a final antigraffiti protection with GRAFFÍ DEFEND This treatment will allow an easy maintenance and an immediate renovation of protection. The underpass tunnel as it looked before the work. Stone covering is laid both on the internal walls and on side exterior walls. Total stone surface is 3600 sqm ca. It was quoted to complete the job in 7 working days with 4 operators, in the optimum weather conditions. ANTIGRAFFITI TREATMENT Examples of intervention
La pulizia preliminare con SERVICE ACIDO diluito al 20%, per eliminare le tracce di polvere di lavorazione della pietra, di posa, di pulviscolo atmosferico. Questo lavaggio è necessario per migliorare le prestazioni della protezione, come evidenziato dai test. L’applicazione a spruzzo di GRAFFÍ FOND seguita dall’uniformazione. Una squadra di 2 operatori è sufficiente per coprire grandi superfici in tempi brevi. Il tunnel dopo l’apertura al traffico veicolare a 2 mesi dall’intervento, durato materialmente 5 giorni lavorativi. L’aspetto naturale della pietra è rimasto intatto Underpass Fortezza da Basso, Florence, Italy – opened to traffic in september, 2004 Wall covering of a tunnel made of Santafiora sandstone ANTIGRAFFITI TREATMENT Examples of intervention
Total surface is about 20000 sq.mts of stone and 4000 sq.mts ca of porphyry: Both materials need preliminary cleaning to remove alterations. Application tests of protection by means of GRAFFÍ FOND and GRAFFÍ DEFEND, to verify the absence of chromatic effect Museum of Contemporary Art MART of Rovereto, Trento Exterior wall made of Pietra di Vicenza (soft limestone) ANTIGRAFFITI TREATMENT Examples of intervention For the whole outdoor covering a yellow variety of Pietra di Vicenza was used. The stone is a fossiliferous biocalcarenite (porous limestone) with a high absorption. Outdoor pavement is made of Tridentin Porphyry (hard stone, similar to granite).
GRAFFI’ ESTRATTORE In some situations removal can be made easier by using other Geal’s products: Estrattore Sverniciante, to remove thick paints and enamels Service Linfosolv, to remove graffiti from wood Estrattore Alcale, to remove uncommon graffiti made with lipstick, wax paints, etc. for the complete removal from porous materials and residual spots (“ghosts”) GRAFFÍ TERGENT For the removal from painted surfaces or delicate surfaces, not resistant to acids, alkalis, solvents Physical-mechanical methods also used REMOVAL OF GRAFFITIS BY CHEMICALS
GRAFFI’ TERGENT Neutral selective detergent Rinse can be manual or by pressure washer Carry out preliminary tests REMOVAL FROM TREATED SURFACES
Graffì FOND Graffì TERGENT Graffì DEFEND PROTECTION ON TREATED SURFACES Antigraffiti Treatment Not needed on hard surfaces such as polished marble, ceramic tiles, etc For maintenance reapply GRAFFÍ DEFEND After any washing