[PDF]    http://dx.doi.org/10.3952/lithjphys.47206

Open access article / Atviros prieigos straipsnis

Lith. J. Phys. 47, 221–228 (2007)


CLEANING OF CONTAMINATED PAPER WITH THE SUBNANOSECOND Nd : YAG LASER PULSES
V. Švedas, A.S. Dement’ev, E. Murauskas, and N. Slavinskis
Laboratory of Nonlinear Optics and Spectroscopy, Institute of Physics, Savanorių 231, LT-02300 Vilnius, Lithuania
E-mail: svedas@ktl.mii.lt

Received 20 April 2007; revised 18 May 2007

Laser cleaning and restoration of documents on the paper base offer advantages over traditional mechanical and chemical cleaning methods. In this work, the office-type paper artificially contaminated for research purposes was cleaned with subnanosecond laser pulses. Laser cleaning recovered more than 80% of the paper initial brightness observed in the visible range, whereas chemical modifications of the paper studied by the FTIR spectrometer were below the spectrometric noise level. The laser fluences above the optical breakdown threshold of the paper surface resulted in the uplift of the paper surface and thinning-out of cellulose fibres in the breakdown zone. This type of morphological modification is accompanied by the FTIR detected compositional changes of the substrate – the intensity of three CaCO3 infrared peaks decreases after laser treatment.
Keywords: paper, laser cleaning, Fourier Transform Infrared (FTIR) spectroscopy, photoacoustic spectroscopy
PACS: 82.80.Gk, 82.80.Kq


UŽTERŠTO POPIERIAUS VALYMAS SUBNANOSEKUNDINIAIS Nd : YAG LAZERIO IMPULSAIS
V. Švedas, A.S. Dementjev, E. Murauskas, N. Slavinskis
Fizikos institutas, Vilnius, Lietuva

Tirtas anglies milteliais užteršto rašomojo popieriaus valymas aktyvios kokybės moduliacijos Nd : YAG lazeriu su priverstinės Brijueno sklaidos impulsų spūda (0,15 ns impulso trukmė ir >10 mJ energija). Valant popierių nefokusuota spinduliuote (impulso energijos tankis ~0,1 J/cm2), valymo būdas yra švelnus. Šiuo būdu nuvaloma anglis ir lazerio spinduliuote atstatoma daugiau nei 80 % popieriaus pirminio baltumo. Švelnų valymą lydintys cheminiai popieriaus pokyčiai yra žemiau FTIR spektroskopijos aptikimo ribos. Veikiant popierių fokusuota spinduliuote (impulso energijos tankis ~5 J/cm2), gaunamas stiprus poveikis, kuris sukelia popieriaus paviršiaus pakilimą ir celiuliozės skaidulų išretėjimą. FTIR pralaidos, atspindžio bei fotoakustiniams matavimams paruošiamas ~1 cm2 popierius plotas, atliekant kompiuteriu valdomą X–Y skenavimą. Stipraus poveikio sukelti morfologiniai popieriaus pakitimai yra lydimi cheminių pokyčių. Skaidulų išretėjimą lydi CaCO3 spektrinių smailių ties 1793 ir 874 cm–1 bei 2514 cm–1 juostos intensyvumų sumažėjimas, kurį galima paaiškinti kalcio karbonato koncentracijos sumažėjimu. 1650–1627 cm–1 intervalo spektrinių juostų intensyvumų kitimai siejami su popieriuje adsorbuoto vandens kiekiu.
Fotoakustinė spektroskopija leidžia atlikti cheminės sudėties spektrinę analizę, įskaitant pasiskirstymą bandinio gylyje. Stipraus lazerio poveikio sukelti sandaros pokyčiai suteikia popieriui savybių, palankių fotoakustinei spektroskopijai – signalas padidėja nuo 3 iki 10 kartų, pagerėja modifikuoto popieriaus atsparumas fotoakustinio signalo įsisotinimo reiškiniui.


References / Nuorodos

[1] M. Alava and K. Niskanen, The physics of paper, Rep. Prog. Phys. 69, 669–723 (2006),
http://dx.doi.org/10.1088/0034-4885/69/3/R03
[2] W. Kautek, S. Pentzien, P. Rudolph, J. Krüger, and E. König, Laser interaction with coated collagen and cellulose fibre composites: Fundamentals of laser cleaning of ancient parchment manuscripts and paper, Appl. Surf. Sci. 127–129, 746–754 (1998),
http://dx.doi.org/10.1016/S0169-4332(97)00735-6
[3] J. Kolar, M. Strlič, S. Pentzien, and W. Kautek, Near-UV, visible and IR pulsed laser light interaction with cellulose, Appl. Phys. A 71, 87–90 (2000),
http://dx.doi.org/10.1007/PL00021097
[4] J. Kolar, M. Strlič, and M. Marinček, IR pulsed laser light interaction with soiled cellulose and paper, Appl. Phys. A 75, 673–676 (2002),
http://dx.doi.org/10.1007/s003390201309
[5] K. Ochocińska, A. Kamińska, and G. Śliwiński, Experimental investigation of stained paper documents cleaned by the Nd: YAG laser pulses, J. Cult. Heritage 4, 188s–193s (2003),
http://dx.doi.org/10.1016/S1296-2074(02)01197-4
[6] C. Pérez, M. Barrera, and L. Díez, Positive findings for laser use in cleaning cellulosic supports, J. Cult. Heritage 4, 194s–200s (2003),
http://dx.doi.org/10.1016/S1296-2074(02)01198-6
[7] P. Rudolph, F.J. Pedersoli JR, H. Scholten, D. Schipper, J.B.G.A. Havermans, H.A. Aziz, V. Quillet, M. Kraan, B. Van Beek, S. Corr, H.-Y. Hua-Ströfer, J. Stokman, P. Van Dalen, and W. Kautek, Laser-induced alteration of contaminated papers, Appl. Phys. A 79, 941–944 (2004),
http://dx.doi.org/10.1007/s00339-004-2574-5
[8] M. Strlič, V.S. Šelf, J. Kolar, D. Kočar, B. Pihlar, R. Ostrowski, J. Marczak, M. Strzelec, M. Marinček, T. Vuorinen, and L.S. Johansson, Optimization and online acoustic monitoring of laser cleaning of soiled paper, Appl. Phys. A 81, 943–951 (2005),
http://dx.doi.org/10.1007/s00339-005-3268-3
[9] Lasers in the Conservation of Artworks. LACONA V Proceedings, Osnabruck, Germany, September 15–18, 2003, eds: K. Dickmann, C. Fotakis, and J.F. Asmus (Springer-Verlag, Berlin–Heidelberg, 2005)
[10] P. Pregowski, J. Marczak, and A. Koss, Thermal effects on artwork surfaces cleaned with laser ablation method, Proc. SPIE 5146, 226–235 (2003),
http://dx.doi.org/10.1117/12.500118
[11] A. Koss and J. Marczak, Application of Lasers in Conservation of Monuments and Works of Art (Warsaw, 2005)
[12] M. Bicchieri, S. Ronconi, F.P. Romano, L. Pappalardo, M. Corsi, G. Cristoforetti, S. Legnaioli, V. Palleschi, A. Salvetti, and E. Tognoni, Study of foxing stains on paper by chemical methods, infrared spectroscopy, micro-X-ray fluorescence spectrometry and laser induced breakdown spectroscopy, Spectrochim. Acta B 57, 1235–1249 (2002),
http://dx.doi.org/10.1016/S0584-8547(02)00056-3
[13] G. Bitossi, R. Giorgi, M. Mauro, B. Salvadori, and L. Dei, Spectroscopic techniques in cultural heritage conservation: A survey, Appl. Spectrosc. Rev. 40, 187–228 (2005),
http://dx.doi.org/10.1081/ASR-200054370
[14] J.F. McClelland, R.W. Jones, and S.J. Bajic, in: Handbook of Vibrational Spectroscopy, vol. 2, eds. J.M. Chalmers and P.R. Griffiths (John Wiley & Sons, Chichester, 2002) pp. 1231–1251
[15] K.H. Michaelian, Photoacoustic Infrared Spectroscopy (John Wiley & Sons, New Jersey, 2003),
http://dx.doi.org/10.1002/0471721190
[16] J. Łojewska, P. Miśkowiec, T. Łojewski, and L.M. Proniewicz, Cellulose oxidative and hydrolytic degradation: In situ FTIR approach, Polymer Degr. Stab. 88, 512–520 (2005),
http://dx.doi.org/10.1016/j.polymdegradstab.2004.12.012
[17] J. Łojewska, A. Lubańska, P. Miśkowiec, T. Łojewski, and L.M. Proniewicz, FTIR in situ transmission studies on the kinetic of paper degradation via hydrolytic and oxidative reaction paths, Appl. Phys. A 83, 597–603 (2006),
http://dx.doi.org/10.1007/s00339-006-3529-9
[18] L. Jacinavičius, A. Michailovas, and E. Murauskas, Generator of short laser pulses, Patent of Republic of Lithuania, LT 5168 B (2004) [in Lithuanian]
[19] A. Dement'ev, R. Buzelis, E. Kosenko, E. Murauskas, and R. Navakas, Solid-state lasers with pulse compression by transient stimulated Brillouin and Raman scattering, Proc. SPIE 4415, 92–97 (2001),
http://dx.doi.org/10.1117/12.425476
[20] A.C. Tam, Applications of photoacoustic sensing techniques, Rev. Mod. Phys. 58, 381–427 (1986),
http://dx.doi.org/10.1103/RevModPhys.58.381
[21] E. Martin, The role of thermal properties in periodic time-varying phenomena, Eur. J. Phys. 28, 429–445 (2007),
http://dx.doi.org/10.1088/0143-0807/28/3/005
[22] J. Coates, in: Encyclopedia of Analytical Chemistry, ed. R.A. Meyers (John Wiley & Sons Ltd, Chichester, 2000) pp. 10815–10837
[23] NIST Chemistry WebBook. Calcium carbonate (precipitated),
http://webbook.nist.gov/chemistry/,
http://dx.doi.org/10.18434/T4D303
[24] J.M. Olinger, P.R. Griffiths, and T. Burger, in: Handbook of Near-Infrared Analysis, eds. D.A. Burns and E.W. Ciurczak (Marcel Dekker, New York, 2001) pp. 19–51
[25] P. Geladi, D. MacDougall, and H. Martens, Linearization and scatter-correction for near-infrared reflectance spectra of meat, Appl. Spectrosc. 39, 491–500 (1985),
http://dx.doi.org/10.1366/0003702854248656
[26] T. Isaksson and T. Naes, The effect of multiplicative scatter correction (MSC) and linearity improvement in NIR spectroscopy, Appl. Spectrosc. 42, 1273–84 (1988),
http://dx.doi.org/10.1366/0003702884429869