This study employed vanillin-modified gelatin to develop a vanillin/gelatin-based leather finishing agent with effective antibacterial properties (GGV). The film structure was systematically characterised using Fourier Transform Infrared Spectroscopy (FTIR) and X-ray Diffraction (XRD), while the antibacterial efficacy and key application performance of the coated leather were comprehensively evaluated. FTIR and XRD results confirmed the successful formation of crosslinks between vanillin and gelatin, indicating effective chemical interaction. Experimental data demonstrated that leather samples coated with the GGV solution (test diameter: 3mm) produced an inhibition zone of approximately 8mm, reflecting strong antimicrobial activity. Moreover, the incorporation of GGV not only increased the tensile strength from 623N/mm to 687N/mm but also improved the leather's softness, resistance to yellowing, and abrasion resistance, thereby enhancing its overall performance .
This study successfully synthesised a polysiloxane modified waterborne polyurethane (SiWPU) emulsion using double-ended hydroxypropyl silicone oil (HP-PDMS) as the silicon-modified monomer for waterborne polyurethane (WPU). Citric acid-modified chitosan (CAMC) was prepared via the acylation reaction of citric acid with chitosan. Layer-by-layer assembly technology produced a CAMC/SiWPU leather finishing agent. FTIR and XPS analyses confirmed the successful incorporation of the organic silicon monomer into the WPU chain segments. FTIR and SEM characterisation demonstrated that citric acid successfully modified chitosan. Analysis results confirm that the silicon monomer has been successfully incorporated into the WPU segments, and chitosan has also been successfully modified by citric acid. Performance testing indicates that the latex film exhibits an excellent water contact angle of 121.95 degrees, demonstrating outstanding hydrophobicity. Leather samples (test specimen diameter 5mm) treated with the CAMC/SiWPU emulsion exhibited a bacterial inhibition zone diameter of approximately 15mm against E. coli, demonstrating good antibacterial properties. Furthermore, the incorporation of CAMC and silicon monomer significantly improved the tensile strength, softness, rubbing fastness and yellowing resistance of the leather samples.
This paper addresses the issue of revealing industry structural differentiation and development trends through the economic performance evaluation of listed companies. Based on the "Brand Evaluation Index System for the Leather Industry" and combined with macroeconomic and importexport data of the leather industry from 2022 to 2024, 12 representative listed companies were selected as research subjects. Using the weighted comprehensive scoring method and linear interpolation method, a comprehensive economic performance evaluation system was constructed for systematic analysis. The study indicates that China's leather industry has moved away from extensive scale expansion and entered a new stage of high-quality development guided by "efficiency and value." The industry chain exhibits a significant differentiation of "strong intermediate goods and weak end products," with the value focus structurally shifting toward high-value segments in the mid-to-upstream. Leading companies dominate industry standards and profit margins, mid-tier companies focus on niche segments, and low-efficiency production capacity at the tail end is being gradually eliminated, forming a "three-layer competitive ecosystem" that continues to solidify. Green low-carbon practices and digitalisation have become key competitive factors in the industry, serving as the core driving forces for companies to achieve differentiated breakthroughs and for the restructuring of value along the industrial chain.
The stains and subsequent treatment of leather are important considerations for conservators in museums, libraries, and archaeological sites. Blood staining is of particular concern because it can weaken the leather fibres underneath and lead to discolouration of historical leather. This study aims to evaluate traditional materials and different gels in the cleaning process of blood stains found on the surfaces of historical leather. Leather samples stained with blood were prepared and exposed to thermal ageing at 80 degrees C to simulate historical stained leather samples. Ethyl alcohol diluted with distilled water at 50% and 70%, and sodium hydroxide at 3% and 5%, were prepared for the study. Additionally, gels such as gellan, laponite and magnetic gels were prepared for evaluation in the cleaning process. The evaluation process for cleaning involved visual assessment, digital USB microscope examination, scanning electron microscope analysis, colour change measurement, pH measurement, and Attenuated Total Reflection Fourier Transform Infrared Spectroscopy (ATR-FTIR). The results of visual examination and various microscopes showed that mechanical cleaning removes part of the blood stain and does not completely remove it, and sometimes causes scratches. Cleaning with different gels significantly improved the surface appearance of the skin compared to chemical or mechanical cleaning. The results also showed that there was a significant change in colour differences in chemical and mechanical cleaning, and less in cleaning with gels. ATR-FTIR results showed that the use of magnetic gel significantly improved the chemical stability of the treated samples better than traditional cleaning methods. This study recommends using cleaning gels, especially magnetic gel, to clean blood stains from archaeological leather artifacts.
Based on the constructed natural suede moisture permeability visualisation model, the backward elimination method was employed for iterative term screening, resulting in an optimised model containing 10 key terms. Through systematic statistical validation, mechanistic interpretation, and parameter optimisation, a closed-loop validation of the model was completed, and its predictive performance and generalisation ability were comprehensively evaluated. The response surface model is shown to maintain excellent fitting characteristics (R-2 = 0.7706, Predicted R-2 = 0.7372). Analysis of variance indicates the model is highly significant (P < 0.0001). Contribution rate analysis identifies temperature as the most influential factor affecting moisture permeability (contribution rate 16.37%), followed by thickness (14.89%). The dominant role of the temperature factor is successfully validated by this method, and the interaction effect between temperature and thickness is confirmed to be the most significant, reflecting the synergistic mechanism of thermal driving force and diffusion path resistance. Based on model interpretation, the optimal process parameters for suede are determined as a thickness of 0.90mm, a temperature of 60 degrees C, and a time of 1.00 hour, with an optimal moisture permeability rate of 12.5436kg/m(2)& centerdot;24h. Validation experiments indicate that the relative error between predicted and measured values is less than 5%, and under conditions of parameter fluctuation, the optimised solution maintains 96.45% performance stability. Through a complete statistical modelling-optimisation-validation workflow, rigorously verified process conditions and a theoretical basis for regulating the moisture permeability performance of suede are provided. The established response surface model validation and optimisation methodology is considered to offer reference value for the process development of functional porous materials
Today, increasing numbers of chemical elements are presenting very important problems and threatening environmental health. The main part of the pollution load in aquatic systems comes from industrial wastes. The leather industry, which emerges as one of the important industries, is considered in terms of its potential for pollution. Unlike the physical, chemical and advanced treatment methods used for the removal of micro-contaminants that are released during the transformation from the raw skin to the finished leather, the use of immobilisation polymers with enzymes known as catalysts is suitable for waste water removal in the leather industry or in other sectors, in order to reduce the effects of environment pollution. In this case, the covalent immobilisation method between the Trametes versicolor laccase enzyme and the epoxy group containing p(HEMA-AGE) was optimized, and the degradation conditions of Acid Black 210 dye were investigated. The results were compared with waste dye water which was released after dyeing in the leather industry.
It was found that the type of adhesive used to bond the shavings affected the hot pressing process and the properties of the finished product. The neoprene adhesive is directly poured into the chrome leather shavings, and the slab needs to be dried and activated in the oven at 60 degrees C for 2 similar to 4min. The optimal hot pressing process conditions are 20% sizing, 7 degrees C, 5min, 3MPa. Pure water should be added to the natural latex adhesive to dilute it, and then the chrome leather shavings are added into the emulsion, the slab does not need to be dried and activated, the best hot pressing process conditions are 21% sizing, water application ratio of 2.5:1, 100 degrees C, 4min, 5MPa. Due to the obvious differences in molecular weight, chemical composition, glass transition temperature, surface free energy and microscopic morphology of the two adhesives, the water absorption and surface wettability of RL (leather fibres) /Natural Latex are higher than that of RL/Neoprene Adhesive but the air permeability and water vapour permeability are lower than that of RL/NA. The mechanical strength of RL/NA is better than that of RL/NL (regenerated leather / Natural Latex) .
With the rapid development of the tanning industry, a large amount of chrome-containing filter residues produced by the utilisation of chrome-containing leather scraps has become an urgent problem needing to be solved. It is imperative to develop an environmentally friendly and efficient In this study, a combination of high-temperature pyrolysis and chemical leaching was performed to resource utilisation of chrome-containing filter residue, and the leaching behaviour and kinetics mechanism of chrome extraction were investigated in detail. Under the following conditions: H2SO4 mass fraction of 40%, liquid-solid ratio of 8mL/g, leaching temperature of 90 degrees C and leaching time of 5 hours, the leaching rate of chrome could reach 87.86%. In addition, sour (pickled) skins tanned with a regenerated chrome tanning agent, which was produced from the leached chrome liquid, could reach a shrinkage temperature of 100.1 degrees C. The results of kinetic analysis showed that the leaching process and pyrolysis filter residue were controlled by product layer diffusion and surface chemical reaction. The activation energy of the chrome leaching reaction was calculated to be 73.79 kJ/mol. This study provides a theoretical basis for the effective utilisation of chrome-containing filter residue in the leather industry.
This investigation deals with purely physical techniques which are employed in utilising leather wastes. Usually such work involves treatment of waste liquors and part processed skin wastes whilst here, In this case, we are dealing with the re-use and re-valuation of partly or completely processed solid chrome leather waste. The scheme involves the mechanical disruption of the waste by various grinding techniques followed by blending with adhesive to re-form a product which may possibly be referred to as a leather composite It is found that the grinding method, and the detailed shape and size of the chromium leather shavings has a direct effect on the physical and mechanical properties of the composite materials which are prepared from the shavings. In this paper, the ball grinding method of chromium leather chips was chosen and designed by orthogonal experiment and the influence of the ball grinding method on the mechanical properties of the chromium leather chips composite made using natural latex as adhesive was analysed. The results showed that the degree of influence of the grinding was highly significant. On this basis, the influence mechanism of ball grinding of chromium leather chips on the mechanical properties of the composite was further analysed.
Aiming at the Carbon Peaking and Carbon Neutrality goals which were clearly put forward after the China leather products import and export volume values change problem, this article adopts a theoretical analysis, statistical data analysis and numerical visualization method from the China leather industry main products import and export trade volumes value analysis of the "Dual Carbon" goal formulation. Following the leather products trade development characteristics, we arrive at the China leather industry import and export trade response and assist with the "Dual carbon" target conclusion. The research shows that: taking the import and export amounts as a benchmark, China's leather main products as a whole showed a trade surplus trend. The travel categories of goods and bags and the shoes and boots products export volumes have been growing steadily. The two categories of China's leather products export amounts accounted for the largest proportion. China's leather industry import and export trade actively responded to the national "Dual carbon" goal, the import and export product structure, market share and import and export trade mode optimization and upgrading and the accompanying series of measures. China's leather industry import and export trade development situation is basically stable, the future will adhere to the green low-carbon development scheme to boost the industry's green upgrading and transformation, so as to enhance the added value of Chinese leather products and market competitiveness.
This paper mainly analyzes the tear strength of different parts of cattle and sheep leather, and analyzes the reasons for the differences in tear strength from a microscopic perspective. The sampling of cattle and sheep leather in different parts was carried out and the tear strength data of different parts of cattle and sheep leather were obtained based on the unilateral tear experiment, and the mechanical properties were further analyzed. After the study, it was found that the tear strength of the cattle in the direction parallel to the spine was: neck> belly> back> butt, and the tear strength of sheepskin was: belly> neck> back> butt. Perpendicular to the spine, the tear strength of the cowhide is: neck> back> belly> butt, and the tear strength of sheepskin is: belly> back> neck> butt. The tear strength of sheepskin is generally less than that of cowhide. SEM images and collagen fibre weaving analysis showed that the tear strength of cowhide was greater than that of sheepskin due to differences in collagen orientation, porosity, and fibre bundle diameter. The proportion of the corium and the tightness of the collagen fibres make the tear strength difference between different parts of the cowhide, and tanning will have a greater impact on the parts with tighter fibre weaving. The proportion of the grain, the direction and tightness of collagen fibre weaving affect the difference in tear strength of each part of the sheepskin to a certain extent.
In this study, "correlation analysis" was used to calculate the physical and mechanical property index data of the prepared composite materials. After preparing such composites with neoprene/chromium leather fillings and adding 15% of pineapple leaf fibre, we examined the properties of RL/NA/PLF tensile strength and elongation at break, tensile strength and collapse strength, elongation at break and collapse height, permeability and 15min water absorption, permeability and 24h water absorption, 15min and 24h water absorption, 24h water absorption and surface wetting, tensile strength and 15min water absorption, tensile strength and 24h water absorption, tensile strength and 24h water absorption, resistance. The results showed that the correlations between tensile strength and surface wettability, collapse strength and permeability, collapse strength and 15min water absorption, collapse strength and surface wettability are opposite to the corresponding indexes of RL/NA. This result is due to the pineapple leaf fibre itself having high strength, low elongation, good water absorption and good air permeability characteristics, which give these results when coupled with the interaction with neoprene adhesive and chrome tanned leather collagen fibre.
A novel fluoro-silicone modified waterborne polyurethane emulsion was synthesized by using alcohol hydroxy-fluorosiloxane as the fluoro-silicone modified monomer of WPU (water-based polyurethane), and the GO/FSiWPU leather finishing agent was prepared by blending with graphene oxide (GO). The structure of FSiWPU emulsion and latex film was analyzed by FT-IR and XPS. The water contact angle, bacteriostatic and other application properties of the coated leather were also tested. FT-IR and XPS analysis showed that the fluorine silicon monomer was successfully introduced into the WPU chain segment. The contact angle of latex film to water is 121.95 degrees. The antibacterial experiment showed that the diameter of Escherichia coli inhibition zone was about 10 mm in the leather sample coated with GO/FSiWPU emulsion (leather sample test diameter was 5 mm), indicating that the coated leather sample had excellent antibacterial performance. At the same time, the addition of GO and fluorosilicon monomer also improved the tensile strength, softness, yellowing resistance and wear resistance of the leather sample..
Based on the concept of waste utilization, pineapple leaf was added in the preparation of chromium leather shavings composite material. The extraction and treatment methods of pineapple leaf fibre, the blending and compatibility with chromium leather shavings, and the influence mechanism on the physical and mechanical properties of the composite material were discussed. The results showed that the pineapple leaf fibre must be soaked with degumming before use; Pineapple leaf fibre molecules contain a large number of hydroxyl groups, a small number of carboxyl and aldehyde groups, which are homogenous with collagen fibre. These groups make the two macromolecules which have strong adsorption and affinity, and can form hydrogen bonds, ionic bonds, covalent bonds, van der Waals forces, electrostatic attraction, coordination and so on. When properly added, longer pineapple leaf fibres can play a physical entanglement and "bridging" role in the component system, reduce the aggregation of collagen fibres, and thus improve the performance of the composite.
In this study, the delimed and bated cattle hide was pre-tanned with 2% TWS tanning agent, after salt-free pickling the pre-tanned leather was combination-tanned using TWLZ tanning agent. The results showed that, with this combined tanning system, the shrinkage temperature of the TWSTWLZ tanned leather increased with increasing the amount of TWLZ tanning agent. When the amount of TWLZ was 6%, the moisture and heat resistance of the crust leather tended to be balanced, and the shrinkage temperature reached the peak of 84.5 degrees C. Compared with conventional TWLZ tanning, the shrinkage temperature of the combined-tanned leather increased by 12.1 degrees C; the dispersion of TWLZ was much more even in the cross-section of leather, showing an increasing uptake rate as well, thus leading to a flat and fine grain surface, full body, no loose fibres, and higher mechanical strength of the combined-tanned leather. The TWS-TWLZ stepwise combined-tanning system represents a clean chrome-free tanning process. Details of the products used are restricted for commercial reasons but the detailed manner in which the process results are examined add to the presentation. Some details are given in the appendix.
On the basis of full macroscopic experiments this paper, further combined with microscopic testing methods was used to analyse the tear strength,of different parts, of top grain leather and genuine leather both of natural cow leather origin, and we also studied the real reasons for the differences in their tear strength. The unilateral tear test was used to obtain values for the tear strength of different layers of cowhide, the cross-sectional microscope images of the different layers of cowhide were obtained by SEM microscopy. After the study, it was found that the strength of top grain leather was greater than that of genuine leather, except for the back, which showed higher tear strength in the direction perpendicular to the spine. The tear strength of cowhide is affected by the superposition of the proportions of corium, fibre density and fibre weave direction, resulting in differences in tear strength between different parts and directions. The tear strength of the corium layer is inversely correlated with the fibre density The order of cowhide tear strength for different layers is: grain layer + corium layer> corium layer> grain layer. Note: The descriptions "Top Grain Leather" and "Genuine Leather" only refer to the two different leather types - Top Grain Leather is the whole substance of the hide grain layer + corium whilst Genuine Leather is corium only i.e. with the grain layer split off.
ln recent decades anc ent parchment study has rece ved much attent on A though the number of i parchment studies has increased, there is currently no bib liometric perspective addressing this topic. The purpose of this study was to analyse the intellectua l base and academic research frontier using C iteSpace , a b ib liometr ic v isua lisat ion and ana lys is software . We retr ieved 164 art ic les pub lished in print or online as early-access articles between 2008 and 2023 from the Web of Science through a , topic search related to parchment. Then, we analysed synthesised networks of co-authorship , , (authors, institutions, countries), co-citation (authors, documents, journals), and co-occurring keywords were analysed. The annua l publication output has trended upward since 2008. Authors , , based in Italy accounted for 29.3% of the tota l publications, followed by England (16.5%), and overall, publications from Europe were the most influentia l. Such evidence also hints at the historical , trajectory of the spread and use of parchments. Based on keyword analysis, micro-Raman , , spectroscopy, Paleolithic bone surface microtopography, European cultura l heritage, non-invasive molab investigation and art forgeries are among the most studied methods. The major research themes identified included the characterisation of parchment samples using spectroscopic techniques, the ageing mechanism and protection of parchment paper, the conservation and anti- counterfeiting of cultura l heritage objects. Emerging themes included proteomic studies and molecular biology analysis. It is foreseeable that future research on parchment or even cultural , heritage w ill be characterised by the tendency toward non-destruction and digitalisation, as we ll as multidisciplinary intersection and parallelism of multiple means to deepen our understanding of ancient parchment.
In view of the economy of China's leather industry after the COVID-19, this paper uses data statistics and numerical visualisation to explore the changes of profit income, import and export volume, industrial sales income and sales market share of China's leather industry in recent years, and analyses the measures taken by China's leather industry to expand domestic demand and stimulate consumption to promote market recovery in response to the economic fluctuations caused by the epidemic. The research shows that: during the epidemic period from 2019 to 2020, the economy of China's leather industry experienced a sharp decline, and then although it rebounded, the industry status continued to be sluggish, and the industry faced huge pressure challenges. In international trade, the Belt and Road has opened a new business path for China's leather industry. In 2020, the industry 's exports exceeded 100 billion US dollars for the first time, and the trade surplus has been widening to form an advantage. At the same time, the proportion of imported industrial structure in China's leather industry gradually shows the trend of China's import market shifting to consumption-oriented; in the future, China's leather industry needs to adjust its industrial structure, promote the innovation and upgrading of industry technology products to expand its advantages, and constantly expand overseas emerging markets to reduce the negative impact of international trade barriers.
This work was aimed at establishing the measuring method for determination of Nhydroxymethylacrylamide and acrylamide in leather by liquid chromatography-mass spectrometry. Methanol was used as the extraction solvent and water bath oscillation extraction was used to extract NMA and AM in the,analysed leather, the limitations of determining two substances using gas chromatography-mass spectrometry, were to optimize the instrument analysis conditions and set the sample pre-treatment conditions .The results showed that the linear range of the method was 0.10 mu g/mL-1.50 mu g/mL. The method's detection limit was at the range of 1.35mg/Kg-1.68mg/Kg, the recoveries ranged from 94.1% to 97.0%, and the relative standard deviation was in the range of 3.4%-5.1%, characterization of positive samples was by using Fourier transform infrared spectroscopy. 60 batches of real leather samples were tested, and the results of this method show that it is suitable for the detection of NMA and AM in leather.
China is a major tanning country. The tanning industry has been presented with new challenges as carbon reduction targets are set. There are three main types of tanning processes in China: traditional chrome tanning, reverse process tanning and chrome-free tanning. In order to better study the environmental impact assessment of the tanning process, this thesis adopts the eFootprint software and uses the PEF evaluation indexes to carry out a qualitative and quantitative environmental impact assessment of the three tanning processes. The results show that the chromium-free tanning process has a relatively low environmental impact. Conventional chrome tanning has the greatest environmental impact on ET. The reverse chrome tanning process has the highest environmental impact on EP.
