THE QUANTITATIVE TESTING AND COMPARISONS OF PEEL AND LAP/SHEAR FOR LASCAUX 360 H.V. AND BEVA 371
Kenneth B. Katz
THE TECHNOLOGIES OF LINING PICTURES to auxiliary supports appear to be headed away from penetrating adhesives, towards nonpenetrating adhesives with lower heat activations or no heat activation at all. Most comparisons and “testing” have been individual efforts using intuitive assessments to evaluate the results. Gustav Berger began quantitative tests (lap shear and peel) of adhesives specific to conservation in the 60's,1 and the latest results of Alan Phenix and Gerry Hedley2 produce more relevent data. Empirically, in the laboratory, I have seen that the bond strengths produced by heat activation of Lascaux 360 H. V. were less than solvent activation of the same adhesive. It also appeared that these strengths were in the same ranges as flock nap bonds of Beva 371.3 Furthermore, I had seen the impregnation of original canvas with B-724 done routinely in Italy when performing cold linings, and wanted to see if that affected the strengths of the bonds produced. The purpose, therefore, of my testing was to measure and record the results of lap/shear and peel tests ofof a relatively new adhesive, Lascaux 360 H. V. and compare it to the bond strengths of BEVA 371 when the two adhesives were used in relatively the same manner, that is, when the adhesives were solvent activated or heat activated. Sizing on the reverser of the original canvas was performed on half the samples to see the effect sizing had on the strengths of the bonds.