Foxing, which manifests as small, circular spots of yellow, brown, or reddish-brown hues on paper-based materials like drawings, books, and printed matter, is an unwanted form of damage. This deterioration is prevalent across various papers, from anci...
Foxing, which manifests as small, circular spots of yellow, brown, or reddish-brown hues on paper-based materials like drawings, books, and printed matter, is an unwanted form of damage. This deterioration is prevalent across various papers, from ancient ones with profound historical and cultural importance to contemporary productions. It's not merely an aesthetic issue that diminishes their value; in severe cases, it can lead to structural damage, weakening the paper's strength. As a result, preservation efforts become necessary.
This paper seeks to offer a foundational comprehension of foxing and its ongoing research trends by reviewing past studies from active overseas research. Additionally, it aims to propose conservation strategies specifically tailored for addressing foxing issues in Korea. Despite extensive studies on foxing over time, its causative factors and formation processes remain unclear. In recent years, investigations have linked foxing to oxidation and discoloration phenomena. These common traits of foxing induce paper damage irrespective of its origin. Hence, this paper concentrates on elucidating the repercussions of foxing and furnishes practical directives for mitigating these effects through experimental methodologies. Experiments examining oxidation and discoloration revealed that foxing undergoes greater oxidation compared to the surrounding paper. Moreover, the discoloration observed in foxing can be
influenced by the oxidation of cellulose. Using these findings as a foundation, we investigated preservation techniques aimed at alleviating oxidation and discoloration. In traditional Korea, ancient writings and drawings were commonly crafted using paper or fabric as their primary materials, often involving a process known as lining, which includes affixing multiple layers of paper to the back. When these writings or drawings face damage, traditional methods and materials are employed to enhance their preservation. The experiment involved two types of samples. The first type encompassed foxing observed on each page resembling books or documents. The second type involved foxing found within pictures resembling traditionally lined paintings. To effectively address the primary issues of oxidation and discoloration caused by foxing on damaged paper, the main methods used in foxing treatment currently involve cleaning and bleaching. Therefore, in the experiments, we conducted treatment tests based on preservation methods such as wet cleaning, wet cleaning with
suction, wet cleaning with bleaching, and standalone bleaching. Subsequently, degradation experiments were carried out to confirm the effectiveness and stability of these preservation techniques. In all experimental samples, both the acidity and the extent of discoloration in the foxing stains were effectively reduced. Discoloration was successfully removed using the traditional preservation method of washing treatment. Washing treatment with suction, alongside suction, proved more effective in removing discoloration from the cellulose structure. Washing treatment with bleaching and standalone bleaching significantly contributed to a more effective discoloration removal compared to samples treated solely with deionized water. While subsequent artificial degradation tests aiming to assess stability didn't exhibit significant alterations, both types of bleached samples showcased additional damage attributed to stains that weren't initially present. This was particularly evident in the case of lining painting samples, which displayed further harm due to fresh stains on the replaced backing paper. Despite the considerable efficacy of bleaching compared to using deionized water alone, the conducted artificial degradation tests aimed to affirm result stability ended up causing additional damage due to previously non-existent stains, indicating the advisability of avoiding bleaching. Once foxing appears on paper, it becomes difficult to reverse. Hence,
prioritizing preventive measures against foxing before it manifests on paper surfaces is crucial. Additionally, continuous research is essential to develop methods for treating paper affected by foxing.