why we need to conserve cultural...
TRANSCRIPT
11/8/2011
1
New Tools for Conservation of Cultural Heritage
Piero Baglioni
Chemistry Department & CSGI y pUniversity of Florence Italy
Why we need to Conserve Why we need to Conserve Cultural Heritage?Cultural Heritage?
Why we need to Conserve Why we need to Conserve Cultural Heritage?Cultural Heritage?
•The conservation of our Cultural Heritage is fundamentalf i t f t ti lt t ditifor conveying to future generations our culture, traditions, and ways of thinking and behaving.•Conservation has an impressive impact on our society from a political, sociological and anthropological points of view.•It is not restricted to ART (paintings) but comprises:
paper documentswood conservationwood conservationstone conservationmagnetic and optical data storage supports, etc.
•Tourism is the largest industrial activity [email protected]
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Modern Conservation Science
It is well accepted that modern Conservation Science
originated from the tragic floods that devastated Florence and
Venice in 1966, imposing the search for new methodologies to
restore and conserve the immense Cultural Heritage heavily
damaged by the flood.
FlorenceFlorence’’s flood s flood -- 19661966
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Ultima Cena - Taddeo Gaddi (14th century), Santa Croce Refectory, Florence
What was conservation before Florence flood?
serendipity and “trial and error” have been the most frequent design principles of formulations for either
cleaning or consolidation of works of artg
What were the consequences?
the past has witnessed a number of actively detrimental treatments, such as the application of inappropriatetreatments, such as the application of inappropriate materials to wall paintings, which can irreversibly jeopardize the appearance (or even the continued
existence) of irreplaceable works of art
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The new Science for Conservation hasdeveloped following two main streams:
(i) the analytical characterization of the materials( ) yconstituting the works of art, the characterization of thepictorial technique used by the artists, and the chemicalreactions involved in their degradation
(ii) the search for new scientific methods for therestoration/conservation, that would allow thetransfer of our Cultural Heritage to futuregenerations
CONSERVATION SCIENCE
Diagnostics and analysesfor conservation and restauration
Material Sciences
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DIAGNOSTICS
Chemical, physical, mineralogical, biological techniques
MicroscopyMicroscopy
FT-IR
SEM-EDX
IBA techniques (PIXE, PIGE)
XRF
XRD
Chromatographyg p y
Colorimetry
Imaging techniques
PCR
DNA genome…
DIAGNOSTICS
The diagnostic protocol
- Preliminary evaluation of the artwork conservative issue
- Choice of the appropriate analytical techniques
- Sampling (if needed)
- Analysis and results interpretation
- Scientific report with guidelines for possible conservation intervention on the artwork
- Evaluation of the intervention results
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ANALYSES FOR CONSERVATION AND RESTAURATION
Monitoring of the environmental and microclimatic parameters.
Archeometric dating, determination of the provenience and evaluation of the authenticity of artworks.
Classical scientific methods for the Classical scientific methods for the restoration/conservationrestoration/conservation
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The search for new scientific methods for the restoration/conservation
A combination of different technologies allows today’s
conservators to provide, in each restoration step, interventions
respectful of the physicochemical characteristics of the
materials used by artists.
Examples are related to systems belonging to soft
matter/nanoscience :1)1) NanoparticlesNanoparticles2)2) MicellesMicelles3)3) MicroemulsionsMicroemulsions4)4) Physical and chemical gelsPhysical and chemical gels5)5) Responsive gelsResponsive gels6)6) NanoNano--spongessponges
CSGICSGICONSORZIO
INTERUNIVERSITARIO PER LO SVILUPPO DEI SISTEMI
A GRANDE INTERFASEest. 1993
Piero Baglioni
[email protected]@csgi.unifi.it
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www.csgi.unifi.itUniversities and Associated LaboratoriesUniversities and Associated Laboratories
Bergamo – U.O. CSGIBologna - Associated LaboratoryCagliari U O CSGICagliari – U.O. CSGICampobasso - U.O. CSGICatania - U.O. CSGIFlorence – Sede, U.O. CSGIMilan-Politecnico - Associated LaboratoryMilan-University - Associated LaboratoryNanomaterials Laboratory - CSGI LaboratoryNaples - U.O. CSGIPavia - U.O. CSGPisa (SNS) - U O CSGIPisa (SNS) U.O. CSGIPerugia - Associated LaboratoryRome - Associated LaboratorySiena - U.O. CSGIUdine - U.O. CSGIVenice - Associated Laboratory
Research Activity of CSGIResearch Activity of CSGIResearch Activity of CSGIResearch Activity of CSGI
The main goal of CSGI is the preparation and study of new SUPRAMOLECULAR and COLLOIDAL SYSTEMS, and the
development of their industrial applications in pharmaceutics, bio-medical, inks and paintings, oil and energy, metallurgic, detergents,
cosmetics, textile, paper, food industry, de-polluting procedures, conservation of works of art, and so forth.
CSGI is also intended to provide Industrial Companies with the BASICCSGI is also intended to provide Industrial Companies with the BASIC SCIENTIFIC AND TECHNOLOGICAL KNOWLEDGE to improve and
optimize specific industrial processes .
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Academic Partners
The CSGI Research is particularly devoted to the The CSGI Research is particularly devoted to the development of the following research areas:development of the following research areas:
The CSGI Research is particularly devoted to the The CSGI Research is particularly devoted to the development of the following research areas:development of the following research areas:
• Nanotechnologies– Grafting on textiles– Nanomaterials (peculiar mechanical, electronic and catalytic properties)- Magnetic Fluids (seals, lubricants, etc.) - Nanobiomedicine (nanoparticles, ibrid systems..)
• Soft Matter ( Micelles, Emulsions, Vesicles, etc.)– Colloidal Dispersions (Fuels, Drugs, Inks, Metals, Coal, etc.)– Micro and Nano-compartmentalized Reaction Sites (Micelles, Vesicles, etc.)– Polymerization in Emulsions, Mini-Emulsions and Micro-emulsions– Interfacial and Structural Properties of Bio-surfactants– Controlled Release of Pharmacological and Non-pharmacological Products
G l F ti f G l d S l G l T iti– Gels, Formation of Gels and Sol-Gel Transition– Inclusion Compounds and Host-Guest Systems
• Conservation of Cultural Heritage– Restoration of paintings– Protection against aging of paper
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Soft Matter in Florence• Self-assembly of biomimetic, responsive
surfactants and of biomacromolecules
M ti it• Magnetic nanocomposites (Core-shell nanostructures with tunable
magnetic properties )
• Nanomaterials and polymers for the conservation of cultural heritage (25% of our activity)
• Nanostructured surfaces for biosensing and LED• Nanostructured surfaces for biosensing and LED Applications
• Additives for cements (with MIT)
• Hydration properties in confined [email protected]
We have ALL the competences for a complete conservation process: from diagnosis of degrade to the conservation intervention
CSGI-actual network
the conservation intervention. CSGI is mainly concentrated in the formulation of new methodologies for conservation. However, diagnostic and virtual reality are active from partners that cooperates with CSGI. We cooperate for the diagnostic with CNR (also laser cleaning and subsequent reconsolidation with nanoparticles) and INFN (PIXE, 14C, etc..).
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•• Virtualization for cultural heritageVirtualization for cultural heritage
•• IDEA ExpertiseIDEA Expertise•• IDEA ExpertiseIDEA Expertise
•• Web Interfaces for Cultural HeritageWeb Interfaces for Cultural Heritage
•• Databases for Cultural HeritageDatabases for Cultural Heritage
•• HardwareHardware
Virtual RealityVirtual Reality•• Virtual RealityVirtual Reality
•• Computational spectroscopyComputational spectroscopy
•• Analysis of compoundsAnalysis of compounds
Virtualization for cultural heritage
Computational modeling recently received significantattention also in the cultural heritage field, withrelation to restoration and conservation of artworksthanks to its capability to offer insights into the naturethanks to its capability to offer insights into the natureand composition of the artistic materials as well as todescribe the physical and chemical changes thatbrings to degradation processes responsible for theartworks modifications.
Chemical characterization of the constitutingmaterials allows researchers to unravel the richinformation enclosed in a work of art, providingan insight into the manufacturing techniquesand revealing aspects of artistic, chronological,historical, and sociocultural significance.
New emerging technologies as virtual reality, storage techniques for heterogeneous data, and the sharing of information about different domains of expertise allow new approaches in studying and handling the cultural heritage.
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•• Immersive virtual gallery providing CAVE Immersive virtual gallery providing CAVE 3D technology:3D technology:
Virtual Reality
3D technology:3D technology:– Different wall positioning;
– Operated through the GPU cluster;
– Stereoscopic projection;
– Software per VR Immersive systems.
•• 3D as an interface for visualization of3D as an interface for visualization of•• 3D as an interface for visualization of 3D as an interface for visualization of cultural heritage data:cultural heritage data:– Enabling interactivity on data: virtual reading,
comparisons between items;
– Augmented reality environments.
Our contribution to the Conservation of Cultural
Heritage (new methods):
Mural paintings: Ferroni-Dini method
C l i H d id ( ti l )
Our contribution to the Conservation of Cultural
Heritage (new methods):
Mural paintings: Ferroni-Dini method
C l i H d id ( ti l )
Conservation of Cultural Heritage
Calcium Hydroxide (nanoparticles)
Paper Deacidification and Cavas Conservation (nanoparticles)
Polymers Removal from artefacts usually damaged from
previous restorations
Wood: Vasa warship in Stockholm (nanoparticles)
Organ pipes conservation (nanoparticles)
Calcium Hydroxide (nanoparticles)
Paper Deacidification and Cavas Conservation (nanoparticles)
Polymers Removal from artefacts usually damaged from
previous restorations
Wood: Vasa warship in Stockholm (nanoparticles)
Organ pipes conservation (nanoparticles)
Oil and easel paintings (chemical gels and microemulsions)
Basically we have developed the methodologies to restore and
conserve most of the cultural heritage
Oil and easel paintings (chemical gels and microemulsions)
Basically we have developed the methodologies to restore and
conserve most of the cultural heritage
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01/26/2003 7:46 PMNanotechnology restores flaking frescos. 01/26/2003 7:46 PMNanoparticles save paper
NANOPARTICLES FOR CONSOLIDATION NANOPARTICLES FOR CONSOLIDATION AND DEACIDIFICATIONAND DEACIDIFICATION
updated at midnight GMT today is sunday, january 26
search nature science update go advanced search
Nanotechnology restores flaking frescos.An off-the-wall application of tiny particles re-unites paintand plaster.11 July 2001
PHILIP BALL
Had Leonardo da Vinci known about nanotechnology, his Last Supper might not be in its present sorry state. Italian chemists have shown that particles of slaked lime - a staple of the Renaissance palette - just a few millionths of a millimetre across can rescue old frescoes from decay.
Leonardo's painting is one of the worst affected by the ravages of time. The
•Nanotechnology solders on22 June 2001
•Circuit training28 February 2001
• Cross winds dirty Med25 October 2002
• Infrared reveals Old Masters' hidden intentions25 October 2002
• Wine buffs tongue-tied25 October 2002
• Palm-tops to guide tourists24 October 2002
updated at midnight GMT today is sunday, january 26
search nature science update go advanced search
Nanoparticles save paper
A sprinkling of slaked lime conserves old documents.22 October 2002
PHILIP BALL
Tiny particles of a strong alkali are helping preserve historical documents.
Piero Baglioni of the University of Florence and his coworkers have treated manuscripts dating back to the fourteenth century with a sprinkling of calcium hydroxide grains just 200 millionths of a millimetre across.
The nanoparticles of what is commonly called slaked
li t t b t ' fib Th b t th
•Physicists tell ripping yarns15 October 2002
•New fight over old map1 August 2002
•Nanotechnology restores flaking frescos.11 July 2001
• Cross winds dirty Med25 October 2002
• Infrared reveals Old Masters' hidden intentions25 October 2002
• Wine buffs tongue-tied
Acids slowly break down the cellulose fibres in paper.© GettyImages
damage was largely the result of ill-informed experimentation withmaterials - Leonardo was no chemist. Similar fresco deterioration is a commonproblem for conservators.
Piero Baglioni and colleagues from the University of Florence havesalvaged a lesser-known
work: Gli Angeli Musicanti painted in the sixteenth century by Santi di Tito in the Santa Maria del Fiore Cathedral in Florence. This image is disfigured where flakes of paint-impregnated plaster, having lifted off the wall below, are threatening to fall off, damaging the painting irreparably.
Before Italian painters began to use canvas in the fifteenth century, many made frescoes. They applied pigment directly to damp plaster on a wall, so that it bound fast as the plaster dried. Giotto and Michelangelo were masters of this technique.
Done skilfully, the results were robust. Unfortunately half a
24 October 2002
• Physicists flip a qubit24 October 2002
A beautiful bottom - thanks to the restorative effects of nanotechnolgoy.
Page 1 of 2http://www.nature.com/nsu/010712/010712-8.html
lime penetrate between paper's fibres. They combat the ravages of acids introduced when paper is made, without altering documents' apperance . The technique is cheap and green and could also be used on canvas.
1
The researchers subjected one nineteenth-century sample to accelerated ageing by keeping it in a hot, moist environment for three weeks. Untreated, the paper turned a deep brown because of acid damage. A treated sample showed very little discolouration.
Neutral territory
Before the nineteenth century, paper was made primarily from shredded rags; thereafter wood pulp has been used. Acids slowly break down the cellulose fibres in paper, making it yellow, brittle and weak.
Currently museum conservators and librarians use chemical treatments to prevent or retard this degradation. A common method, the Book-keeper process, involves scattering grains of magnesium oxide over the paper. These stick to the fibres and react with water to form an alkali that neutralizes acids.
25 October 2002
• Palm-tops to guide tourists24 October 2002
• Physicists flip a qubit24 October 2002
Page 1 of 2http://www.nature.com/nsu/021021/021021-1.html
RESTORING THE CONSERVEDRESTORING THE CONSERVEDRESTORING THE CONSERVEDRESTORING THE CONSERVED
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RESTORING THE CONSERVEDRESTORING THE CONSERVEDRESTORING THE CONSERVEDRESTORING THE CONSERVED
RESTORING THE CONSERVEDRESTORING THE CONSERVEDRESTORING THE CONSERVEDRESTORING THE CONSERVED
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1)1) Nanoparticles for consolidation and Nanoparticles for consolidation and deacidificationdeacidification (frescoes paper and wood)(frescoes paper and wood)
Nanoscience for ConservationNanoscience for Conservation
deacidificationdeacidification (frescoes, paper and wood)(frescoes, paper and wood)
2) How soft materials can be modified to obtain 2) How soft materials can be modified to obtain responsive materials, to confine molecules, to responsive materials, to confine molecules, to upload or release soft/hard materials:upload or release soft/hard materials:
ii) ) MicroemulsionsMicroemulsions and and micellarmicellar solutionssolutions
ii) Physical, Chemical and Responsive Gelsii) Physical, Chemical and Responsive Gels
Nanoparticles contribution to the conservation of Cultural Heritage:
• Mural paintings: Calcium Hydroxide Nanoparticles (strontium and
barium)
Nanoparticles contribution to the conservation of Cultural Heritage:
• Mural paintings: Calcium Hydroxide Nanoparticles (strontium and
barium)barium)
• Paper de-acidification and Canvas conservation (calcium,
magnesium, strontium hydroxide and carbonate nanoparticles)
• Wood - VASA warship, Stockholm (calcium and magnesium
hydroxide and carbonate nanoparticles)
O i ti ( l i d i h d id
barium)
• Paper de-acidification and Canvas conservation (calcium,
magnesium, strontium hydroxide and carbonate nanoparticles)
• Wood - VASA warship, Stockholm (calcium and magnesium
hydroxide and carbonate nanoparticles)
O i ti ( l i d i h d id• Organ pipes conservation (calcium and magnesium hydroxide
and carbonate nanoparticles)
• Organ pipes conservation (calcium and magnesium hydroxide
and carbonate nanoparticles)
11/8/2011
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01/26/2003 7:46 PMNanotechnology restores flaking frescos. 01/26/2003 7:46 PMNanoparticles save paper
NANOPARTICLES FOR CONSOLIDATION NANOPARTICLES FOR CONSOLIDATION AND DEACIDIFICATIONAND DEACIDIFICATION
NANOPARTICLES FOR CONSOLIDATION NANOPARTICLES FOR CONSOLIDATION AND DEACIDIFICATIONAND DEACIDIFICATION
updated at midnight GMT today is sunday, january 26
search nature science update go advanced search
Nanotechnology restores flaking frescos.An off-the-wall application of tiny particles re-unites paintand plaster.11 July 2001
PHILIP BALL
Had Leonardo da Vinci known about nanotechnology, his Last Supper might not be in its present sorry state. Italian chemists have shown that particles of slaked lime - a staple of the Renaissance palette - just a few millionths of a millimetre across can rescue old frescoes from decay.
Leonardo's painting is one of the worst affected by the ravages of time. The
•Nanotechnology solders on22 June 2001
•Circuit training28 February 2001
• Cross winds dirty Med25 October 2002
• Infrared reveals Old Masters' hidden intentions25 October 2002
• Wine buffs tongue-tied25 October 2002
• Palm-tops to guide tourists24 October 2002
updated at midnight GMT today is sunday, january 26
search nature science update go advanced search
Nanoparticles save paper
A sprinkling of slaked lime conserves old documents.22 October 2002
PHILIP BALL
Tiny particles of a strong alkali are helping preserve historical documents.
Piero Baglioni of the University of Florence and his coworkers have treated manuscripts dating back to the fourteenth century with a sprinkling of calcium hydroxide grains just 200 millionths of a millimetre across.
The nanoparticles of what is commonly called slaked
li t t b t ' fib Th b t th
•Physicists tell ripping yarns15 October 2002
•New fight over old map1 August 2002
•Nanotechnology restores flaking frescos.11 July 2001
• Cross winds dirty Med25 October 2002
• Infrared reveals Old Masters' hidden intentions25 October 2002
• Wine buffs tongue-tied
Acids slowly break down the cellulose fibres in paper.© GettyImages
damage was largely the result of ill-informed experimentation withmaterials - Leonardo was no chemist. Similar fresco deterioration is a commonproblem for conservators.
Piero Baglioni and colleagues from the University of Florence havesalvaged a lesser-known
work: Gli Angeli Musicanti painted in the sixteenth century by Santi di Tito in the Santa Maria del Fiore Cathedral in Florence. This image is disfigured where flakes of paint-impregnated plaster, having lifted off the wall below, are threatening to fall off, damaging the painting irreparably.
Before Italian painters began to use canvas in the fifteenth century, many made frescoes. They applied pigment directly to damp plaster on a wall, so that it bound fast as the plaster dried. Giotto and Michelangelo were masters of this technique.
Done skilfully, the results were robust. Unfortunately half a
24 October 2002
• Physicists flip a qubit24 October 2002
A beautiful bottom - thanks to the restorative effects of nanotechnolgoy.
Page 1 of 2http://www.nature.com/nsu/010712/010712-8.html
lime penetrate between paper's fibres. They combat the ravages of acids introduced when paper is made, without altering documents' apperance . The technique is cheap and green and could also be used on canvas.
1
The researchers subjected one nineteenth-century sample to accelerated ageing by keeping it in a hot, moist environment for three weeks. Untreated, the paper turned a deep brown because of acid damage. A treated sample showed very little discolouration.
Neutral territory
Before the nineteenth century, paper was made primarily from shredded rags; thereafter wood pulp has been used. Acids slowly break down the cellulose fibres in paper, making it yellow, brittle and weak.
Currently museum conservators and librarians use chemical treatments to prevent or retard this degradation. A common method, the Book-keeper process, involves scattering grains of magnesium oxide over the paper. These stick to the fibres and react with water to form an alkali that neutralizes acids.
25 October 2002
• Palm-tops to guide tourists24 October 2002
• Physicists flip a qubit24 October 2002
Page 1 of 2http://www.nature.com/nsu/021021/021021-1.html
CONSOLIDATION OF WALL PAINTINGS CONSOLIDATION OF WALL PAINTINGS AND CARBONATIC STONESAND CARBONATIC STONES
Ca(OH)2 + CO2 CaCO3 +
H2O
Ch i l D d ti
CaCO3 + H2SO4 + H2O CaSO4.2H2O + CO2
Chemical Degradation
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Beato Angelico
Pre-restoration Without restoration
BeatoBeato AngelicoAngelico
PrePre--restorationrestoration PostPost--restorationrestoration
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Beato AngelicoPre-restoration
Post-restoration
De-sulphation of frescoesSan Marco in Florence
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nanoparticles application
nanoparticles application
11/8/2011
20
NANOPARTICLE APPLICATIONNANOPARTICLE APPLICATION
Ca(OH)2 + CO2 CaCO3 + H2O
A new setting process
Portion of a wall painting in the “Cappellone degli Spagnoli” (Chiostro Verde in Santa Maria Novella, Florence). Before (left) and after (right) the restoration
PrePre--consolidation of frescoconsolidation of frescoby limeby lime--propanpropan--11--ol dispersionol dispersion
PrePre--consolidation of frescoconsolidation of frescoby limeby lime--propanpropan--11--ol dispersionol dispersion
, ) ( ) ( g )
[email protected]@csgi.unifi.it
11/8/2011
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Portion of a wall painting in the “Cappellone degli Spagnoli” (Chiostro Verde in Santa Maria Novella Florence) Before (left) and after (right) the restoration
PrePre--consolidation of frescoconsolidation of frescoby limeby lime--propanpropan--11--ol dispersionol dispersion
Maria Novella, Florence). Before (left) and after (right) the restoration
[email protected]@csgi.unifi.it
WallWall paintingspaintings byby SantiSanti didi TitoTito
Calcium hydroxide nanoparticles applied on frescoes
WallWall paintingspaintings byby SantiSanti didi TitoTito(XVI(XVI century)century) ‘Gli‘Gli AngeliAngeliMusicanti’Musicanti’ onon thetheCounterfaçadeCounterfaçade ofof thethe SantaSantaMariaMaria deldel FioreFiore CathedralCathedral ininFlorenceFlorence.. TheThe regionregion inin thetheboxbox hashas beenbeen treatedtreated withwithnanonano particlesparticles;; (top)(top) beforebeforethethe restoration,restoration, (bottom)(bottom) afterafter
thethe restoration,restoration, (bottom)(bottom) afterafterthethe restorationrestoration..
11/8/2011
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The city was inhabited for more thantwelve centuries starting around 400 b.C.(Pre Classic period) and was slowlyabandoned until the year 900 A.D. (PostClassic period) reaching its maximum
CALAKMUL
Classic period), reaching its maximumdevelopment between 600-800 A.D. (LateClassic period).
MESOAMERICAN PAINTINGSMESOAMERICAN PAINTINGS
MAYA AT CALAKMULMAYA AT CALAKMUL
May 2005
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Nanoparticles application in Calakmul
Consolidation of powdered paints, showing decorative glyphs, ubicated in the basement of columns in the structure XX of the Gran
Acropolis.
Fase 1
Step 3
“Estructura 1-4”Recently excavated wall paintings
[email protected] May 2005 September 2005
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Red box shows area where nanoparticles were used to fix the colors
Wiew of the “Murales” after complete excavation
[email protected] Arqueologo Ramon Carrasco Vargas
11/8/2011
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CHOLULA
Proceso de consolidación con hidróxido ce calcio antes y después
CHOLULA CHOLULA --MEXICOMEXICO
POLYMERS REMOVAL + NANOPARTICLESPOLYMERS REMOVAL + NANOPARTICLESPOLYMERS REMOVAL + NANOPARTICLESPOLYMERS REMOVAL + NANOPARTICLES
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The paintings discovered in 2005 in Calakmul,
and treated with NANORESTORE®Acropolis Chik Naab
Building 1
Arqueologo Ramon Carrasco Vargas
Conservation of Paper
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Degradation of paper
VerbaVerba volantvolant, , scriptascripta manentmanent . . . . . .
THE VASATHE VASATHE VASATHE VASA
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Alkaline nanoparticles for PAPER DEACIDIFICATION
acidification
pH=7 pH=3.5
Hydrolysis of glycosidic bonds(cellulose depolymerization)
Mg(OH)2
PAPER(cellulose) DEGRADATION
HYDROLYSIS OXIDATION
acids Light, pollution, metals impurities
Changes in the mechanical properties
C iColor change
Corrosion
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TM ions - formation of peroxides in ACIDIC MEDIUM:
Fe2+ + O2 + H+ → Fe3+ + HOO.
Fe2+ + HOO. + H+ → Fe3+ + H2O2
Homolytic decomposition of peroxides by TM ions:
Fe2+ + H2O2 → Fe3+ + HO- + OH. Fenton reaction
Cu+ + H2O2 → Cu2++ HO- + OH. Fenton-related reaction
- OH. (H+(aq): E0=+2.8 V)
- Peroxides formation in ALKALINE MEDIUM, in presence of O2 , favoured by TM ions according to a not well defined mechanism
- Regeneration of TM by reducing substances: Superoxide O2
.- , gallic acid, reducing end groups of [email protected]
2) Peroxides decomposition (Fenton reaction)
3) Hydroxy radical formation
Oxidation reaction pathways
) y y(OH)
OH + RH H2O + RR + O2 ROO
ROO + R’H ROOH + R’
Metal ions catalytic activity depending on pH
1) Peroxides formation(ROOH) following reactionof cellulose (RH) with O2
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1 METAL
2. RADICAL SCAVENGERS
Act as a‘sacrificial anode’ for cellulose, scavenginghydroxyl radicals and forming stable products
ANTIOXYDANTS
1. METAL DEACTIVATORS
3. PEROXIDE DECOMPOSERS
Reduce the amount of peroxides
Stop the catalytic activity of the transition metal ion by blocking all the active
sites
Quaternary amonium halides
Phytates
Strlic et al, Ageing and stabilisation of paper. National and Library, Ljubiana (2005), 126
TBABr BBABr
Why solid nanoparticles dispersed in propanol?
SIZE Low polar solventHigh carbonatation rate
High penetration and adhesion Compatible with most of
hydro-soluble material
A B
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C
SEM images of a 19th century sample treatedwith calcium hydroxide obtained byhomogeneous phase reaction. Some calcium
C
g phydroxide particles bound to the cellulosefibres are shown. A) bar = 5 �m; B) bar = 5�m; C) bar = 50 �m
Not treated Preventive deacidification
Very goodVery good elasticityweakness
Ink browningNo color change
Aging time 48 [email protected]
11/8/2011
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Can we use the same approach to conserve wood?
AN EXAMPLE FROM DETERGENCY:AN EXAMPLE FROM DETERGENCY:
HOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAINHOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAIN
AN EXAMPLE FROM DETERGENCY:AN EXAMPLE FROM DETERGENCY:
HOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAINHOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAIN
RESTORING THE CONSERVEDRESTORING THE CONSERVED
HOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAIN HOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAIN
RESPONSIVE MATERIALS TO CONFINE MOLECULES TO UPLOAD RESPONSIVE MATERIALS TO CONFINE MOLECULES TO UPLOAD
OR RELEASE SOFT/HARD MATERIALSOR RELEASE SOFT/HARD MATERIALS
Examples from Cultural Heritage ConservationExamples from Cultural Heritage Conservation
HOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAIN HOW THE SOFT MATERIALS CAN BE MODIFIED TO OBTAIN
RESPONSIVE MATERIALS TO CONFINE MOLECULES TO UPLOAD RESPONSIVE MATERIALS TO CONFINE MOLECULES TO UPLOAD
OR RELEASE SOFT/HARD MATERIALSOR RELEASE SOFT/HARD MATERIALS
Examples from Cultural Heritage ConservationExamples from Cultural Heritage Conservation
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Conservation of Cultural Heritage
Conservation of Cultural Heritage
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Since the half of last century conservators have been applying polymeric materials on wall paintings as consolidant and protective coatings.
Polymers In Wall Paintings Conservation
Acrylics (Paraloid, Primal, Elvacite)
Vynil (PVA)
Acrylic/Vynil (Mowilith)
Siliconic resins
30 70
Mural paintings in “Templo de los Nichos Pintados” in Mayapan (Yucatan).
Since the half of the last century conservators have been applying polymeric materials on wall paintings as consolidant and protective
coatings.
POLYMERS IN WALL PAINTINGS CONSERVATION
Acrylics (Paraloid, Primal, Elvacite)
Vynil (PVA)
Acrylic/Vynil (Mowilith)
Siliconic resins
•Easy to use
STRENGHTSSTRENGHTS
•Alteration of the
WEAKNESSESWEAKNESSES
y
•Cheap
•Give immediate aesthetic results
physical-chemical properties of the
material
•Instability to ageing
•Irreversibilty of the treatment (loss of
solubility)[email protected]
11/8/2011
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Since the half of the last century conservators have been applying polymeric materials on wall paintings as consolidant and protective
coatings.
POLYMERS IN WALL PAINTINGS CONSERVATION
Acrylics (Paraloid, Primal, Elvacite)
Vynil (PVA)
Acrylic/Vynil (Mowilith)
Siliconic resins
•Easy to use
STRENGHTSSTRENGHTS
•Alteration of the
WEAKNESSESWEAKNESSES
LOSS OF the WORK LOSS OF the WORK OF ART OF ART in a time in a time scale depending scale depending from the climatic from the climatic
conditions (from 10 conditions (from 10 to 50/60 yrs)to 50/60 yrs)
y
•Cheap
•Give immediate aesthetic results
physical-chemical properties of the
material
•Instability to ageing
•Irreversibilty of the treatment (loss of
solubility)[email protected]
CHOLULA - polymers
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Removal of acrylic resins Removal of acrylic resins applied in previous restoration applied in previous restoration
workshops (Venice)workshops (Venice)
Removal of acrylic resins Removal of acrylic resins applied in previous restoration applied in previous restoration
workshops (Venice)workshops (Venice)
Fresco by Lorenzo di Pietro called “Vecchietta”; Spedale di S. Maria della Scala (Siena). Detail of the paint after the application of an o/w microemulsion applied to remove a surface layer of an acrylic polymer
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Fresco by Francesco Vecellio (Tiziano’s cousin, XVI century); S. Salvador Church Sacristy (Venezia). Detail of the paint before (left) and after (right) the restoration. The removal of the surface layer of an
acrylic polymer has been carried out by means of application of a o/w microemulsion
Archaeological site of Mayapan
Mowilith DM5
CEANING WITH [email protected]
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Archaeological site of Mayapan
Taormina, 27 Settembre 2010
Archaeological site of Mayapan
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AEPC/Annunciation grotto- Nazareth Basilica
Innovative gelswith confined solvents
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Gel visco-elastici di PVA/borace
Emiliano Carretti, Scilla Grassi, Manuela Cossalter, Irene Natali, Gabriella Caminati, Richard G. Weiss, Piero Baglioni and Luigi Dei,Weiss, Piero Baglioni and Luigi Dei, “Poly(vinyl alcohol)−Borate Hydro/Cosolvent Gels: Viscoelastic Properties, Solubilizing Power, and Application to Art Conservation”, Langmuir, 2009, 25), 8656-8662.
New Nanomagenetic gels for polymer or New Nanomagenetic gels for polymer or organics removalorganics removal
New Nanomagenetic gels for polymer or New Nanomagenetic gels for polymer or organics removalorganics removal
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Playing with gel structure: diffusion of the confined phase
soft gelhard gel
No micellar solution - microemulsion spreading fromthe hard gel
Cleaning tests: Mowilith DM5
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Cleaning tests: Plexisol P550
Partlycleaned
hard gel (sol. mic.) on vacuum table (left) and before cleaning (right)
not cleaned
Conclusions
We developed several methods using the Nanoscience framework for the conservation of
the Cultural Heritage g
Micelles, microemulsions, gels, responsive gels, nanoparticles are the most important (and the
most powerful systems) so far exploited.
Alth h th th d l th iAlthough these methods are complex, their use and application are simple and can be safely
applied even in areas without scientific infrastructures