Estudo de caso de degradação química de papéis ácidos

Abstract

This research presents a comparative analysis of the suffered degradations for the produced acid paper, trying to characterize the aging of the paper that stayed conditioned by a certain period of time.Printed documents were chosen for the research to avoid influences by other elements as, for instance, the ink gall ink, used in the manuscripts of that period, and whose degradations demand an own evaluation. The study object is part of the collection entitled "Presidentes da Província (Presidents of the Province) that is under the guard of the Arquivo Público Mineiro (State of Minas Gerais Archives). Theperiod of production of papers, chosen for this study, it embraces those produced from 1850 to 1889, for being that a transition time among the rag papers, paper predecessor of superior quality, and the one that would come dominate to the market, the papers produced by wood.Starting from a previous knowledge of factors of interference in the permanence of the paper, experiments were accomplished to show own characteristics of the material and the treatment to which the paste was submitted, presence of components as lignin and nature of addictive as glues. And, also, physical research as tensile strength, bursting strength , and water absorption Cobb method.The results indicate that the characteristics of natural aging specific of each process of production of the paper should be considerate when the restoration procedures will be establish.