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A study of West Sumatran textiles embellished with metal-wrapped weft yarns sampled textiles woven in 14 weaving centers of the highlands. The two general categories to which the textiles belonged were textiles that had threads with metal wires or strips wound around the fiber core and textiles that had threads with the metallic surface applied with adhesive to a cellulosic wrapping wound around the fiber core. Optical microscopy demonstrated significant differences in the construction of the threads. Among the properties described were the fiber type, color, and twist of the core, the thread diameter in microns, the outer surface appearance, the wrapping width, the substrate adhesive color, and the wrapping twist. Elemental analysis of the metal threads measured types and/or ratios of the metals present in the wrapping exterior surface, interior surface, and core.

Several aspects of the biodeterioration of stone are reviewed, including general deterioration mechanisms, deterioration attributed to specific biological organisms, conservation case histories, and treatment options. The literature is cited with emphasis on historic monuments.

Microbiological agents, such as bacteria, actinomycetes, and fungi, degrade cellulose. The most severe deterioration in indoor environments is primarily caused by cellulolytic fungi, resulting in loss of fiber strength and actual material failure. Other microbial spoilage can occur as a result of the permanent staining from pigmentation and mycelial penetration by both cellulolytic and non-cellulolytic fungi, the latter using food sources ranging from starch sizing to surface dirt, and oils. Much has been written concerning biocidal testing against these microfungal agents from an industrial point of view; less from a conservation standpoint. This paper submits a limited review of current literature (c. 25 years) focusing on the information and its relevance for the conservator. The following topics related to cellulosic deterioration by fungal microbes are covered; 1. current theories about the mechanism of cellulolytic attack; 2. biocides which may be employed in fungal control; and 3. choice of environmental conditions as a means of static control of fungal biodegradative agents. An annotated reference list is provided.

In previous studies from the Metropolitan Museum laboratories, metal-wrapped textile specimens were examined by scanning electron microscopy-energy dispersive X-ray spectrometry (SEM-EDS) as well as light microscopy. Pitfalls and difficulties in describing the specimens were enumerated.1 In the present study, samples were taken from Indian textiles in Indian Museums for the sake of describing them in detail. Table I ·lists categories of metal inclusion in textiles which offer guidelines for the description of specimens. Other studies have also defined categories with varying degrees of completeness.2 Among the Indian textiles observed, only categories I, II, and III were noted. This report includes principally examples of categories II and III.

Scanning electron microscopy and energy dispersive x-ray spectrometry (SEM-EDS) has been employed along with the light microscope to describe some metal threads taken from some late Medieval and Renaissance textiles attributed to Italy in the collection of the Metropolitan Museum of Art, New York. Comparisons are made within the group studied and to those descriptions of metal threads found in recent literature. The results are discussed in terms of geographic and historic markers of the metal thread technology employed.

Seven ternary mixtures of gold(80-95%)-silver(4-15%)-copper(1-15%) were prepared as standards for the determination of elemental composition by energy dispersive X-ray spectrometry (EDS). Two geometric forms (flat and oblate) of the standards were prepared for comparison to the analyses of historic gold objects. Surface analyses were performed. Polished sections of the standards were also analysed Comparison between two methods for collecting EDS data is reported. The analyses are discussed in terms of developing a generalized methodology for estimating elemental composition of museum artifacts.

Twelve mordanted and cochineal dyed modem wool samples were subjected to scanning electron microscopy and energy dispersive X-ray spectrometry (SEM-EDS) analysis. The analyses for metallic elements matched in all cases those actually used in the preparation. The mordants detected contained the metallic ele- ments: aluminum, chromium, copper, iron, and tin. SEM photomicrographs were also examined for the effects of mordanting on fiber surfaces. Atomic absorption (AA) analysis of the samples is also reported.

Five commercially available materials were tested as impregnating agents for paper. They were Elvanol 5105, Kelgin LV, Klucel G, Methocel A15C and Viscarin GP209. Whatman no. 1 chromatography was used as support and solutions o.1% and 1% w/v used. Dry oven ageing was at 100 C. For upto 14 days. At the lower concentration none of the solutions increased paper strength, at 1% Kelgin, Methocel and Viscarin only. After ageing Methocel was best, Viscarin the worst (for folding endurance). Colour changes, ph changes were small for all materials. All the materials were completely soluble in water, partially soluble in toluene, after 16 hours at 120 C. Tables, references.

The effects of dry oven accelerated aging on samples of three kinds of paper (Whatman Chromatography #1, Arches Cover Infinity, and Aquabee Newsprint Rough 887-R), washed in three qualities of water (New York City tap water, deionized, and distilled), were observed. Changes in folding endurance, tensile strength, reflectance, color, and pH are reported. Results support findings reported by other researchers that greater purity of wash water is not necessarily beneficial to paper. However, the findings presented here suggest that the acidity of the wash water and the composition of the paper are also factors influencing the effects of the washing treatments.

The cleavage of poly(vinyl alcohol) in dimethyl sulfoxide at 42°C has been measured viscometrically in the presence of tert-butyl hydroperoxide and metal complexes. Phthalocyanine complexes of copper(II), iron(III), cobalt(II), and vanadium as VO(II) as well as hemin, hematin, chlorophyllin, and cytochrome c were used. The rates of decomposition of tert-butyl hydroperoxide in the presence of these metal complexes were measured idometrically. These data are compared to results obtained with other metal complexes in similar reactions.

In the first part of this investigation, the composition and aging behavior of four dry cleaning products (Opaline Pad, Pink Pearl, Magic Rub, and Kneaded Rubber erasers) are studied. The second part consists of an examination of the effects on paper of eraser treatments performed with these products. Changes in folding endurance, tensile strength, surface pH, color, texture, and wettability of aged and unaged samples of Whatman Chromatography paper treated with the four dry cleaning products were observed and are compared with results for untreated controls.Conclusions are that the dry cleaning procedures performed with these products alter surface characteristics but not mechanical properties of the paper. Pink Pearl and Kneaded Rubber erasers altered the paper surface the most while the Magic Rub eraser altered it the least. The Magic Rub eraser was determined to have substantially different organic constituents from the other three products, which have similarities in composition.

(1988). The Evaluation of Metal Wrappings from Medieval Textiles Using Scanning Electron Microscopy-Energy Dispersive X-Ray Spectrometry. Textile History: Vol. 19, No. 1, pp. 3-22.

Thirteen silk fibers from seven different historical silk textiles were subjected to EDS analysis. The major metallic elements detected were aluminum, iron, calcium, silicon and potassium. No evidence for copper, chromium, tin or zinc was found. These results were compared to analyses of known mordanted silk samples.

Scanning electron microscopy and energy dispersive X-ray spectrometry (SEM-EDS) have been employed along with the light microscope to describe some metal threads made of proteinaceous substrates taken from museum textile collections. The textiles are said to originate in Central Asia, Western Asia, and Syria or Egypt, thirteenth/fifteenth century AD. This study extends the set of data obtained in an earlier study of threads from the same time-period. A general methodology for the examination of these types of metal threads is proposed.

Data for the tert-butyl hydroperoxide-initiated polymerization of styrene in dilute benzene solution at 126°C. are presented. These data are discussed in terms of Tobolsky's limiting conversion kinetics. Several rate laws are considered. Simple unimolecular decomposition of the peroxide appears to be unimportant under these conditions, as does solvent interaction.

2-Aryl-N,N'-dimethyl-1,3-imidazolidines and 2-aryl-1,3-dioxolanes were subjected to 70 eV spectral analysis. Fragmentation pathways for both series of compounds are suggested. Aryl vs. benzylic hydrogen fragmentations were subjected to Hammett σ+ ρ plots. Incipient charge on the benzyl carbonium ion was stabilized by electron donating groups in both series of compounds. Dioxolanes were more sensitive to substituent effects (ρ = −0.639) than the imidazolidines (ρ = −0.251) implying that the positive charge on the fragmenting ion is more localized at the benzylic position of the imidazolidines than of the dioxolanes.

An evaluation is presented of a newly formulated impregnating agent, denoted as Regnal “7”, as applied to embrittled book pages. Whole books were treated by dip-impregnation in the World Patent Development laboratories. The treated book pages were cut into strips in both the cross-print and the with-print directions. Tests showed that no significant improvement of deteriorated book-pages was obtained by dip-impregnation with Regnal. Some factors causing difficulty in performing evaluations on book pages are discussed.

The affects of accelerated aging at temperatures of 21°, 60°, 80°, 100°C on Whatman #1 chromatography paper treated with four commercially available glues and paper cements have been observed. Folding endurance, reflectance, objective color and pH of the systems have been measured as well as reversibility in water and toluene of the adhesives applied to glass plates. None of these adhesive materials is recommended for use in paper conservation on the basis of observed properties upon accelerated aging. Conclusions reached on the basis of observations at higher temperatures support results obtained at lower temperatures and longer aging times.

(1972). THE CHEMISTRY AND HISTORY OF THE PIGMENT INDIAN YELLOW. Studies in Conservation: Vol. 17, Lisbon Congress 1972: Conservation of Paintings and the Graphic Arts, pp. 401-408.

Stress relaxation master curves were obtained for polystyrene, polymethyl methacrylate, and polyvinyl chloride, all plasticized with dioctylphthalate. The plasticized polyvinyl chloride results were quite different from the others, and this was tentatively ascribed to borderline crystallinity.

(1971). An Evaluation of Adhesives for use in Paper conservation. International Institute for Conservation of Historic and Artistic Works: Vol. 11, No. 2, pp. 58-75.

A large number of valuable paintings in museum collections are thinly painted on delicate open-weave canvases and are sensitive to solvents ordinarily used in conservation treatments. Environmental stresses cause the paint layer to crack and flake. To save the paintings from disintegration they often must be reinforced by a lining and the paint layer must be readhered. Traditional lining adhesives (wax-resin or glue) may penetrate the paint layer and change its appearance.

The effects of dry oven ageing on Whatman no. Chromatography paper treated with methylcellulose of different viscosities and at different concentrations are reported. The viscosities were 15, 400, 1500 and 4000 cP and the concentrations ranged from 1% w/v to 10% w/v. All treated papers were found to be stronger than untreated papers, with increases related to both increased MW and increased concentration. Factors related to actual use of methyl celluloses on papers of different types and for different needs have not been taken into consideration. Graphs, tables, references.

Samples of modern wool, silk and cotton woven fabrics were mordanted with five common dyeing mor- dants: potassium aluminum sulfate, cupric sulfate, ferrous sulfate, stannous chloride and potassium dichromate. Samples were observed by scanning electron microscopy (SEM) and metallic elements detected by energy disper- sive X-ray spectrometry (EDS). The results and limitations of the detection process are discussed and compared to other analytical procedures. The application of this proce- dure to historical textiles for analysis of metallic mordants and certain dyes is discussed.

A new gas trap has been devised that is easier to construct and more efficient than standard gas traps used in organic laboratories.