Plasma And Nano for New Age “soft” conservation
Objective: to investigate the potential of atmospheric pressure plasmas on the market, and use them as a non-contact cleaning method for artworks. Once the advantages and limitations have been acquired, the aim of the project is to design and manufacture a dedicated atmospheric plasma device for the cultural heritage and restoration field.
The main objective is to develop a novel atmospheric plasma technique for surface cleaning and coating deposition as well as two innovative coatings: a self-diagnostic protective coating and a coating provided with identification marker.
The project aims at integrating the new plasma cleaning/deposition technique and the new coatings in a “full-life” protocol spanning surface cleaning and pre-treatment, deposition of protective and identification coatings, and complete removal of coatings.
The plasma technique is proposed for surface cleaning and coating removal as alternative or complementary to the other non-contact techniques such as laser. This technique is characterized by no thermal heating, selectivity, chemical reduction of oxides, applicability on all substrates and competitive costs.
The self-diagnostic coatings provide a long-lasting solution with an added value of easy and instant diagnostic of coating functionality through a nano-technological approach, reducing monitoring costs and time with no impact on tourist accessibility.
The identification marker coating allows using nanotechnologies to obtain a transparent authenticity proof and cataloguing label.
The compatibility of the new materials with the substrates is guaranteed intrinsically by their integration in the “full-life” protocol because it ensures its complete reversibility. The protocol is applicable on all substrate materials principally as preventing conservation, in the project its validation is proposed on metal substrates (silver and bronze) and on mural paintings, limestone and sandstone.
The project also aims at implementing a demonstrator of the entire “full-life” protocol, which will be used for training cultural operators in organised events and fairs.
An added value is also the strong participation of SME’s as conservation operators and as technological companies, which ensures the possibility of scaling up and placing the new products on the market.
The project tested and validated cultural heritage applications, particularly for stones, metals and mural paintings. Work began with testing five commercially available plasma torches for cleaning applications. The results showed the dangers of excessive heat. Arc discharge plasmas are capable of producing drops of molten metal, verifying that high substrate temperatures or excessively long treatments can also cause damages.
For these reasons the Nadir team built up an innovative portable plasma jet, enabling the removal of organics or the reconversion of oxides and sulfides to metal. The non-contact plasma was environmentally friendly, and did not cause any thermal, mechanical or chemical damage to the artifacts. The same device is also capable of depositing invisible identification marks and protective coatings.
In the subsequent years Nadir successfully patented, certified and commercialized the technology that is now available for similar purposes.