Study On Inking Performance Of Xuan Paper With Different Ripening Degree

As an excellent cultural paper,Xuan paper has been widely used in art creation,calligraphy and painting mounting,cultural relics protection and restoration.Because of its excellent ink,Xuan paper is loved by the literati.But at present,there is still no unified ink-wetting performance standard for Xuan paper.The so-called Xuan paper on the market is not unified and standardized in the market because of the large number of manufacturers and different ingredients,and the cooked Xuan obtained from the raw Xuan to the sizing alum water is different in their respective processes and sizing processes.This will undoubtedly increase the customer’s choice of different degree of maturity Xuan paper difficulty,and is not conducive to Xuan paper as a special high-end cultural paper use norms.Based on this,this study aims to quantify the ink-wetting performance of Xuan paper from the perspective of the ink-wetting performance of Xuan paper with different curing degrees,and explore the mechanism of alum-water curing Xuan paper and its influence on the ink-wetting performance.Firstly,the development history of Xuan paper was reviewed.According to previous studies,the factors affecting the ink wetting performance of Xuan paper were summarized,and the sizing process of Xuan paper was systematically discussed.Secondly,the previous research methods were summarized.The contact angle,the diffusion area of a certain volume of ink droplets,the roundness and aspect ratio of ink droplets and the gray image of ink droplets were used to quantify the ink wettability of Xuan paper.By comparing and analyzing the ink-wetting effects of raw,semi-cooked and cooked Xuan samples produced by five manufacturers,it can be found that the ink-wetting effects of Xuan paper with the same maturity are different due to different manufacturers.The ink-wetting effects of Xuan paper with different maturity do not show regular changes.Then,the Xuan paper from a representative manufacturer is customized,and the inkability of the obtained raw Xuan,3-cooked Xuan,4-cooked Xuan,6-cooked Xuan,8-cooked Xuan and cooked Xuan is analyzed.It was found that the contact angle of Xuan paper increased with the increase of aging degree,and the area of absorption and diffusion of a certain volume of ink droplets on the paper decreased.The ink lubricity of Xuan paper with different curing degree produced by the manufacturer can change regularly,which is mainly caused by different sizing concentration.Finally,different concentrations of alum aqueous solution were prepared to ripen the Xuan paper,and the ink wetting performance was tested after natural drying.The results showed that gelatin was the main reason affecting the ink-washability,while alum did not play a major role in the ink-washability of Xuan paper.Gelatin mass concentration gradient between 0 ～ 1.2wt.%,the ink performance change is obvious,ink droplet halo area gradually reduced,can present regular change.In order to explore the mechanism of action of alum water on Xuan paper,the Xuan papers with different curing degrees obtained by applying different concentrations of alum water were analyzed by SEM and FTIR.The results showed that alum water could fill the gap between fibers,weaken the capillary effect of fibers,and form a hydrophobic film on the surface of paper,thus improving the hydrophobicity and mechanical properties of Xuan paper.With the increase of gelatin concentration,the number of gelatin particles bound to fibers increased.The hydroxyl,some amino and carboxyl groups of gelatin collagen can form many intermolecular hydrogen bonds with the hydroxyl and carboxyl groups of non-ionic regions on the surface of plant fibers,which can reduce the hydrophilic groups on the fiber surface and make the paper obtain hydrophobic properties,thus affecting the ink lubricity of Xuan paper.The main reason for the regular change of ink performance is that the film formed on the surface of Xuan paper cannot completely cover the fiber at low gelatin concentration,resulting in the film between the paper surface and the fiber gap does not exist in a continuous and uninterrupted state,and the ink droplets can still be dispersed between the fibers.With the increase of gelatin concentration,the adhesion between Xuan film between Xuan paper fiber and fiber is more uniform and compact,which can block the penetration and diffusion of ink droplets,thereby affecting the halo area and shape of ink droplets.