Notice bibliographique du personnel « Silver and Acid-thiourea Silver Dips: Rinsing and Aging Monitored by Electrochemistry »
- Titre
- Silver and Acid-thiourea Silver Dips: Rinsing and Aging Monitored by Electrochemistry
- Auteur ou éditeur
- Selwyn, Lyndsie S.
- McKinnon, W Ross.
- Date de publication
- 2020
- Collation
- online
- Titre de la source
- Studies in conservation
- Résumé
- Many conservators are reluctant to use silver dips based on thiourea because of reported
- problems such as yellowing and retarnishing as well as brown spots on daguerreotypes.
- Silver dips are reported to leave a surface layer, which is blamed for these problems. Here, acid-thiourea silver dips (1 M thiourea, pH 2) were studied with samples of pure silver to see whether extensive rinsing can remove the surface layer, and what consequences the layer produces. It was shown that potentiodynamic scans can detect the presence of the surface layer. The electrochemical measurements were used to study the effects of rinsing (different times, different pH) and the effects of aging (28 days, 60°C, 100% relative humidity) on silver samples after immersion in a silver dip. The surface layer is partly modified, but not completely removed, even after 24 h of rinsing. The electrochemical signal of the surface layer is gone after aging. Moreover, dipped silver samples after rinsing do not tarnish more rapidly than samples of clean, polished silver. The problems reported with silver dip may be
- due to thiourea trapped in porosity rather than adsorbed on the surface
- Langue
- English = Anglais
- Sujet
- Silver;
- tarnish;
- dip;
- thiourea;
- rinse;
- aged;
- electrochemistry
- Argent;
- ternir;
- tremper;
- thiourée;
- rincer;
- vieilli;
- électrochimie
- ISBN/ISSN
- 00393630
- Pays
- United Kingdom
- Type de document
- Journal Article = Article de périodique
- Localisation
- #16693
- Clé
- 2130
- Collection
- Staff Bibliography