Research On Deacidification And Reinforcement Of Diazonium Salt Drying Drawing Files

Paper archives protection has always been an important subject in cultural relics protection technology.Paper files are prone to serious diseases such as acidification,yellowing,mildew,moth-eaten,and fading of writing because of the paper itself and the improper storage environment for a long time.Over time,if these precious paper files are not protected by appropriate methods,they will lose their historical information and cultural value.Therefore,it is essential to protect paper archives.As a kind of paper file,blueprints have been widely used in research institutes,design institutes,construction companies and other fields since their invention.In particular,the diazo salt blueprints are cheaper and can be mass-produced,which makes them basically used in China.However,the azo dyes on the diazonium salt drawings are relatively unstable and are very susceptible to the impact of the preservation environment.Some of the diazonium salt drawings have been acidified and the writing has faded.The existing protection method only protects the diazonium salted drawings from the perspective of archives storage,and does not solve the problems of acidification and handwriting discoloration of diazonium salted drawings in the real sense,and lacks preventive measures.This paper mainly studies the serious acidification,decay,handwriting fading and other diseases of diazonium salt blueprints,and develops a diazonium salt blueprints reinforcement.The physical and chemical properties of the diazonium salt blueprint samples before and after the reinforcement were strengthened were analyzed To analyze its deacidification and strengthening effects.Accelerated aging was performed on unreinforced and reinforced drawing simulation samples,and the effect of the reinforcing agent on the durability of the drawings was analyzed.The main work from the following five points of view:The development history of diazo salt blueprints,detailed production methods,and the current status of research on the protection of blueprints were learned by consulting data and literature research.Through field inspections of archives and units'collection of diazo salt blueprints,disease investigation and disease cause analysis were carried out:UV light,air pollution,and special characteristics of blueprints were the main reasons for acidification and handwriting discoloration.The composition and color rendering principle of diazonium salt blueprints were explored The study found that the diazonium salt blueprint is mainly composed of blueprint paper and photosensitizer liquid(coupling agent,and other auxiliaries.),The photosensitizer in the photosensitive liquid can be mixed with the coupling agent to form a diazo compound,which can generate an azo dye in an alkaline environment.Accordingly,a photosensitizing liquid was configured to simulate the process of preparing a diazonium salt blueprint by the primitive method,and a diazonium salt blueprint simulation sample was produced.Aiming at the special properties of diazonium salt blueprints and the main causes of diseases,a diazonium salt blueprint reinforcement was developed.First,the solvents required for the reinforcing agent were screened,and borax boric acid buffer solution was selected for deacidification treatment.Secondly,the diazo salt blueprint handwriting was fixed,and several materials that could be used as ultraviolet resistance were selected for comparison.UV-531 was selected as a UV absorber in the reinforcing agent and formed into a film.Finally,it is determined that this reinforcing agent is mainly divided into two parts:component A is made of borax boric acid buffer solution and aqueous fluorine in a certain ratio,and component B is made of UV-53 land ethyl cellulose in a certain ratio.The deacidification effects and mechanical properties were evaluated.Use dry-heat,wet-heat,ultraviolet three kinds of artificial accelerated aging to carry out aging resistance test on diazo salt blueprint samples before and after strengthening,and compare the pH,folding resistance,tearing strength and tensile strength of the blueprint paper before and after aging to deacidify the paper.The results show that the reinforcing agent can have a good deacidification effect on the diazo salt blueprint,and after the aging of the strengthened samples,the retention rate of various mechanical properties is significantly higher than unreinforced samples.It shows that the reinforcing agent has the effect of deacidifying and strengthening the diazo salt blueprints,and improves the durability of the blueprints.The strengthening effect of the diazo salt blueprint reinforcing agent was further verified The color difference analysis and contact angle test were carried out on the diazonium sheet before and after strengthening.The results showed that the color change of the diazonium sheet did not change significantly after strengthening,and the color difference changed little after ultraviolet light,and the hydrophilicity was also reduced.Further exploring the principle of deacidification of the diazo salt blueprint reinforcing agent,and comparing the micromorphology of the samples before and after strengthening,it was found that this reinforcing agent can strengthen the paper by forming a protective film on the surface of the blueprint paper.Finally,ATR-FTIR was used to analyze the functional groups of the diazonium salt before and after strengthening,and the comparison showed that the paper structure before and after strengthening did not change significantly.