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Sandra Dejvison, FIIC ACRKonzervacija i restauracijastaklenih predmetaČinjenica da je stakleni predmet lepljen i restauriranne može se sakriti. Ovaj činilac ugrožava izgled finalnogrezultata i to uvek treba objasniti vlasnicima ikustosima pre nego što se započne tretman. Materijalipotrebni za konzervaciju stakla su Scotch Magic Tape810® (lepljiva traka), aceton, dejonizovani deterdžent,npr. Synperonic A 7®, destilovana ili dejonizovana voda,lepkovi - Superglue® (cijanoakrilat, tzv. superlepak),HMG® (nitrat celuloze), Paraloid B72® (kopolimer etilmetakrilata i metil metakrilata) i prozirna epoksi smola– Araldite 2020®, Fynebond®, Hxtal-Nyl-1® ili Epotek-301® (za uporednu analizu ovih smola videti S. Davison,Conservation and Restoration of Glass (2003), Butterworth-Heinemann,Slika 5.2, strana 210).Kao i kod drugih materijala, priroda i stanje predmetaodređuju vrstu tretmana. U slučaju stakla, arheološki(iskopani) predmeti mogu da se konzerviraju (madane mogu uvek da se restauriraju), a s druge strane,orošeno staklo i staklo prekriveno mrežom sitnih pukotinasuviše je osetljivo da bi se tretiralo.Većina staklenih predmeta u privatnom vlasništvukoji se daju na tretman restauratorima su antikviteti ilisavremeni predmeti, koji često imaju više sentimentalnunego istorijsku ili ekonomsku vrednost. Neki od njih suprozirni (ponekad se nazivaju «vodenobelim» u konzervatorskojliteraturi). Uz uobičajenu dodatnu pažnju koddelikatnih i dekorisanih površina, ivice preloma se čisteacetonom, kako bi se otklonila prašina i masnoća od rukovanja.Fragmenti se, zatim, spajaju uskim komadimalepljive trake, koje se postavljaju, po mogućnosti, naizmeničnona suprotne strane suda, ali tako da se ne nađujedna nasuprot druge. Korisno je ponekad blago zagrejatistaklo, ali to treba učiniti jako pažljivo. Nakon togase postepeno nanose kapi prozirne smole i razvlače dužpukotine uz pomoć drvenog štapića. Potrebno je sasvimmalo smole. Ona ulazi u pukotine uz pomoć kapilarnesile i u većini slučajeva će prodreti i u deo ispod lepljivetrake. Ako se to ne desi, moguće je smolu naneti još jednom,kada se prva količina stegne. Opšte uzevši, smolubi trebalo nanositi samo sa jedne strane stakla, jer senanošenjem sa obe strane pospešuje stvaranje mehurića.Lepljiva traka nikako ne sme da se uklanja dok se smolane stegne. Takođe ne bi trebalo koristiti vatu natopljenuacetonom za uklanjanje viška smole, osim u slučajukad ona curi, jer aceton može da spreči stezanje. Kadase smola stegne, višak lako može da se ukloni malim144Sandy Davison, FIIC ACRConservation and restorationof glass objectsRepairs and restoration of glass objects cannot normallybe made invisible. This factor limits the appearanceof the final result, and needs to be explained toowners and curators before work is begun. Materials requiredfor glass repair are Scotch Magic Tape 810®, acetone,non –ionic detergent such as Synperonic A7®, distilledor deionised water, adhesives - Superglue® (cyanoacrylate),HMG® (cellulose nitrate and Paraloid B72®(a copolymer of ethyl methacrylate and methyl methacrylate),and an optically clear epoxy resin, Araldite2020®, Fynebond®, Hxtal-Nyl-1® or Epotek - 301®. Fora comparative table of these resins, see Davison, S.(2003). Conservation and Restoration of Glass (Butterworth-Heinemann),Table 5.2 on page 210.As in the case of other types of object, it is the natureand condition of the object that dictates the treatment.In the case of glass it isn’t the case that archaeological(excavated) objects cannot be repaired (althoughit may not be possible to restore it), and at the other endof the spectrum, weeping or crizzling historical glass istoo weak to repair.The majority of privately owned glass objects whichrestorers are asked to treat are likely to be historic orcontemporary, and often have a sentimental rather thanhistoric or financial value. Of these, some will be opticallyclear (sometimes referred to as “water-white” inconservation literature). With the usual caveats concerningdelicate or decorative surfaces, break edges arecleaned with acetone to remove dust and grease fromhandling. The fragments are then held together withnarrow strips of MagicTape, placed where possible onalternate sides of the vessel and staggered i.e. so that thetape are not opposite each other. It may help to warmthe glass gently, but great care must be taken. Drops ofan optically clear resin are then placed at intervalsalong the crack and then drawn together along thecrack with a cocktail stick.Very little adhesive is required.It is drawn into the cracks by capillary action, andin most cases will seep beneath the tapes. If it does not,a second application of adhesive can be applied once thefirst has cured. In general, adhesive should be applied toone side of the glass only, as applying it from both sidesencourages the formation of air bubbles. On no accountmust the tapes be moved until the resin has cured. Neithershould acetone on swabs be used to remove excessresin – except for runs – as this will prevent the resinfrom curing. Once the resin has cured, excess can be carefullyremoved with frequently changed small cottonwool swabs moistened with acetone and/or a blunt scalpelblade, taking care not to scratch the glass. As the resinpenetrates the cracks it will displace the air withinthe cracks, thus rendering less visible. The cracks willthen appear as hairlines in both glass surfaces, unlessthere are tiny chips along the break edges.Resin can also be introduced by capillary action intotraveling cracks. It may help to warm the glass gently,unless the glass has sprung out of alignment inwhich case the crack may lengthen dramatically! Tinychips that do not penetrate through the glass, can be carefullyfilled with drops of resin at a later stage, placingthe glass in such a position that the chip lies uppermostso that the resin finds its own level.Tiny holes can be filledby first backing them with Magic Tape, before applyingresin in a slightly thickened state.