Carole Dignard

BEVA 371 AND ITS USE AS AN ADHESIVE FOR SKIN AND LEATHER REPAIRS: BACKGROUND AND A REVIEW OF TREATMENTS

Abstract Since its introduction in the 1970s, the use of BEVA 371 (solution and film) has expanded from the field of paintings conservation into textiles and objects conservation. During the development of BEVA 371 solution, initial testing was conducted to determine its strength, compatibility, effectiveness, reversibility, and aging qualities in accordance with its intended use in paintings conservation. Its use beyond the treatment of paintings is widespread; however, no comprehensive testing has been accomplished for these specific uses. This article presents a summary of published analyses and testing of BEVA 371 and a review of skin and leather treatments using BEVA 371 solution and film, focusing on the versatility of the adhesive and the variables that affect bond strength. Also presented is a historic overview of the uses of BEVA 371 solution and film on skin and leather. The condition of a group of skin objects that were treated with these BEVA products at the American Museum of Natural History (AMNH) from the mid-1980s through the 1990s was assessed.

A study of the light sensitivity of birch bark

ABSTRACT Birch bark is commonly found in indigenous collections in Canadian museums. It is empirically known that light can cause the cambium side of birch bark to change colour. The purpose of this research is to better assess the light sensitivities of various colours of birch barks, and the manner, degree, and rate of colour change during light exposure. Six barks with different colours were used: beige, yellow, orange, orange-brown, red, and brown. Samples were exposed to daylight through a north-facing window (window), LED light from an enclosed chamber (LED), and the Newport-Oriel microfade tester (MFT). Window and MFT samples received a total light dose of approximately 25 Mlux-hours, and LED samples, 182 Mlux-hours. Colour monitoring of the samples showed that almost all barks initially darkened and then faded. Daylight through window caused the most rapid and extensive darkening and fading. Bluewool (BW) ratings for window samples were the lowest (most light sensitive). The MFT and LED samples showed a similar degree of colour change, with the same dose, despite the difference in intensity. Ratings of MFT samples are within one BW step difference compared to LED samples. The rate and extent of initial darkening depended on the colour of the bark; the middle range orange-toned barks showed the most rapid and extensive darkening followed by fading.