Curling edges: a problem that has plagued scrolls for millennia.
Qi-Wa refers to the up curl on the lengths of hand scrolls and hanging scrolls, which has troubled Chinese artisans and emperors for as long as the art of painting and calligraphy has existed. This warp is unwelcome not only for aesthetic reasons, but its potential damage to the fiber and ink. Although it is generally treated as a part of the cockling and curling due to moisture, consistency of paste, and defects from the mounting procedures, we demonstrate that the spontaneous extrinsic curvature incurred from the storage is in fact more essential to understanding and curing Qi-Wa. In contrast to the former factors whose effects are less predictable, the plastic deformation and strain distribution on a membrane are a well-defined mechanical problem. We study this phenomenon by experiments, theoretical models, and molecular dynamics simulation, and obtain consistent scaling relations for the Qi-Wa height. This knowledge enables us to propose modifications on the traditional mounting techniques that are tested on real mounted paper to be effective at mitigating Qi-Wa. By experimenting on polymer-based films, we demonstrate the possible relevance of our study to the modern development of flexible electronic paper.
Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China.
Ming-Han
MH
Chou
Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China.
Wei-Chao
WC
Shen
Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China.
Yi-Ping
YP
Wang
Department of Registration and Conservation, National Palace Museum, Taipei 11143, Taiwan, Republic of China.
Sun-Hsin
SH
Hung
Department of Physics, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China and Center for Fundamental Science Research, National Tsing Hua University, Hsinchu 30013, Taiwan, Republic of China.
Tzay-Ming
TM
Hong