Oil-soluble Dye Writing Reinforcement Can Be Evaluated

Preservation and reinforcement of paper-based relics is a comprehensive and interdisciplinary subject which crosses material science,environment science,history,chemistry,archive,etc.This subject is so complicated because of diversity of the raw material,the additive in paper-making and storage environment of archives and various inks on manuscripts.Particularly,it is easy for characters on manuscripts written by the ballpoint pen to fade and diffuse.If these archives cannot be protected well,they may lose all the valuable history information.The reinforcement solution made and designed by our laboratory has gone through the test of time and natural environment.This dissertation used different types of paper as the research object to characterize and compare the physical and chemical property of paper and ink.By this way,the mechanism of this reinforcement solution can be revealed to give theoretical support for paper-based relics conservation.The main contents are listed as follows:1.The reinforcement solution was designed to protect the color of characters written by the ballpoint pen and carbon paper."A component" includes mixed phosphotungstic acid,phosphoric acid,ethyl alcohol and distilled water,and "B component" includes barium hydroxide and methyl alcohol.The color precipitation formed by reinforcement solution and oil-soluble dyes can solve problems about color fading and diffusion of characters written by the ballpoint pen and carbon paper.In this way,durability of paper and ink can be improved significantly.2.The UV radiation,dry-heat and moist-heat accelerated ageing were applied on five different papers and ink to test aging resistance of paper samples before and after reinforcement.The tensile strength,elongation percentages,folding strength and tearing strength were measured to evaluate physical properties of paper samples.Color changes were tested to explore the color of paper and ink and pH was used to determine the alkali residue on paper.It was concluded that the reinforced paper samples all presented better physical properties and alkalescency.After UV radiation,the color changes of the reinforced ink samples were less than the untreated.3.The UV-vis spectra was used to test and compare the reinforced paper and ink before and after UV radiation to verify photochromic effect on samples.Phosphotungstic acid barium in the reinforcement solution could form heteropoly blues under UV radiation,which was accordant to XPS results.In this way,paper could be protected well from the damage of light.To further explore effects of the reinforcement solution on paper,five different kinds of paper were still used as object of study.ATR-FTIR could confirm that reinforcement solution did no harm on paper,SEM pictures could observe morphology of cellulose,and contact angle measurement showed that paper had better hydrophobicity.TG curves illustrated that the reinforced paper showed better ageing resistance.4.Based on comparison of untreated and reinforced paper samples from macroscopic and microscopic views,the reinforcement mechanism could be obtained.The reinforcement solution can protonize oil-soluble dyes,and then form color precipitation with barium hydroxide methanol saturated solution.The dye precipitation can adhere to cellulose of paper to realize solidification of ink and cellulose.After that,characters will not fade,diffuse and be damaged by light.As we all know,the main component of paper is cellulose which includes a great deal of O-H,so oxygen atom in the reinforcement solution can form hydrogen bonds with cellulose.Also,the acidic material can be neutralize,which means that this reinforcement solution can deacidify and reinforce paper.Hydrogen bonds can bond cellulose macromolecule closely.In this way,cellulose binding is stronger with showing better mechanical properties.