Journal of The American Leather Chemists Association最新文献

{"title":"Application of Acid Protease for Eco-friendly Pre-treatment of Goat Skin to Improve Antimicrobial Finish Using Herbal Natural Extracts","authors":"Mona Vajpayee, Mumal Singh, Hemen Dave, Lalita Ledwani","doi":"10.34314/jalca.v118i6.7588","DOIUrl":"https://doi.org/10.34314/jalca.v118i6.7588","url":null,"abstract":"Due to its moisture retention capacity and huge surface area, leather is highly prone to microbial proliferation and biodeterioration; hence, leather products desired have an antimicrobial finish. In this study, acid protease enzyme pre-treatment of goat skin was utilized as an eco-friendly substitute for conventional wet-chemical processing. The treatment can impart the desired surface properties to improve the antimicrobial finish with natural extracts obtained from leaves of Azadirachta indica (Neem Tree), Ocimum sanctum (Holy Basil, Tulsi), and Camellia sinensis (Green Tea). The procedure was optimized for different process parameters, including enzyme concentration, pH, material to liquor ratio (MLR), treatment time, and temperature. The effect of the treatment on bulk and surface properties of the skin was characterized by weight loss analysis, X-Ray Diffraction (XRD), Thermal Gravimetric Analysis (TGA), and Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (ATR-FTIR), X-Ray Photoelectron Spectroscopy (XPS), Water contact angle measurement, Scanning Electron Microscopy (SEM) respectively. The effect of the enzymatic treatment on organoleptic properties and the mechanical strength of the skin was also studied. The enzymatic treatment resulted in weight loss, and removal of non-collagen components, thus opening the fibrous collagen matrix of the skin. Hence, the skin treated with acid protease enzyme provides better affinity and accessibility for phytoactive compounds from the natural extracts and better attachment by electrostatic attachment due to an increase in surface functional groups after the enzymatic treatment compared to untreated skin. The effectiveness of the antimicrobial finish was measured as a zone of inhibition and with a modified Hohenstein test against test microorganisms E. coli and S. aureus.Azadirachta indica (Neem Tree) extract showed the highest inhibitory activity (97%) against E. coli, while the Ocimum sanctum (Holy Basil, Tulsi) extract exhibited the highest inhibitory activity (95%) against S. aureus.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"95 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2023-06-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"139372073","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Calcium in Delimed Hide on Leather Quality","authors":"Chao Lei, Xunsen Chen, Yunhang Zeng, Bi Shi","doi":"10.34314/jalca.v118i3.6814","DOIUrl":"https://doi.org/10.34314/jalca.v118i3.6814","url":null,"abstract":"The efficient removal of calcium from delimed hide is essential to leather quality, but few reports have elaborated on how residual calcium in delimed hide affects leather quality. In this study, four delimed hides containing different calcium content were first prepared by using ammonium sulfate and sodium gluconate. Energy dispersive X-ray spectrometry results showed that the atomic percentages of calcium on the grain surfaces of the four delimed hides were 8.17%, 4.82%, 2.34%, and 0.25%, respectively. The bating, chrome tanning, and post-tanning performances of the four delimed hides were then analyzed to evaluate the effect of calcium in delimed hide on leather quality. Results showed that the removal efficiency of non-collagenous protein from hide in enzymatic bating, the evenness of chromium distribution, the shrinkage temperature of wet blue, and the physical properties of crust leather all increased as the calcium content of delimed hide decreased. Furthermore, efficient calcium removal from the grain surface of delimed hide played a key role in the color brightness and uniformity of wet blue and crust leather. The results draw our attention to the importance of considering the effectual removal of calcium from delimed hide for obtaining high-quality leather.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"118 3","pages":"109-116"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://journals.uc.edu/index.php/JALCA/article/download/6814/5462","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147916992","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"An Improved Method for Accurately Determining Total Content of Four Fungicides (TCMTB, OIT, OPP And PCMC) in Leather","authors":"Xuan LEI, He-Wei Ma","doi":"10.34314/jalca.v118i3.6813","DOIUrl":"https://doi.org/10.34314/jalca.v118i3.6813","url":null,"abstract":"Determination of total contents of four fungicides (TCMTB, OIT, OPP and PCMC) in leather is required by Ecolabels due to health risks. Thus, an improved analytical procedure based on the current Standard ISO 13365-1-2020, was investigated to accurately test the total contents of the four fungicides in leather. It was verified that the ultrasonic assisted acetonitrile extraction described in this Standard is only effective for extracting TCMTB, but inefficient for PCMC, OPP and OIT. The extraction efficiency by acetonitrile was 93% for PCMC, 95% for OPP and 89% for OIT, respectively. Methanol was proven to be an optimal alternative of acetonitrile for sample extraction and presented satisfactory extraction efficiencies (~100%) for eluting the four fungicides at a wide content range (80-470 mg/kg). The detection limits were evaluated and well satisfy the requirement by the Ecolabels. Results of HPLC chromatograms from commercial leather samples demonstrated no obvious matrix interferences from methanol extraction. Series of leather samples from different origins were analyzed. TCMTB was found in 86% and OIT in 30% of the total tested samples, which were higher in content than the allowable limits by Ecolabels.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"118 3","pages":"102-108"},"PeriodicalIF":0.0,"publicationDate":"2023-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://journals.uc.edu/index.php/JALCA/article/download/6813/5461","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147905851","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Superhydrophobic Modification of Collagen Fiber","authors":"Shuangfeng Xu, Ya-nan Wang, Bi Shi","doi":"10.34314/jalca.v117i10.6182","DOIUrl":"https://doi.org/10.34314/jalca.v117i10.6182","url":null,"abstract":"Tanning is considered to be the crosslinking reaction between collagen fibers and tanning agents, and a majority of tanning reactions result in suppressed water absorption and enhanced hydrophobicity of leather. However, extensive use of tanning agents may bring a burden to the environment. Herein, to facilitate a sustainable leather manufacturing industry, we propose a revolutionary strategy of “tanning” without tanning agents. Based on this strategy, superhydrophobic collagen fibers (FAS-CFs) were fabricated through dehydration, followed by superhydrophobic modification. Dehydration aimed to eliminate the “sticky” effect of water on collagen fiber to obtain a dispersed hierarchical structure. Superhydrophobic modification not only dispersed and stabilized the fiber structures, but also protected the fiber dispersity from water immersion. Compared with chrome-tanned collagen fibers (Cr-CFs) and glutaraldehyde-tanned collagen fibers (G-CFs), FAS-CFs showed higher hydrophobicity, lower water absorption, and superior mechanical properties. Meanwhile, FAS-CFs exhibited a high thermal denaturation temperature of 92.5°C and retained their original shape after being heated to 100°C. Therefore, our proposed strategy is expected to be a potential substitute for conventional tanning and might contribute to cleaner and sustainable leather manufacturing.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"117 10","pages":"422-431"},"PeriodicalIF":0.0,"publicationDate":"2022-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://journals.uc.edu/index.php/JALCA/article/download/6182/4945","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147915308","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Effect of Pickling Materials on Leather Quality from a Hide Surface Charge Perspective","authors":"Tianqi Yang, Yunhang Zeng, Qingyong Sun, Chao Lei, Bi Shi","doi":"10.34314/jalca.v117i7.5962","DOIUrl":"https://doi.org/10.34314/jalca.v117i7.5962","url":null,"abstract":"Salt-free pickling technology has recently received increased attention because it produces much lower salt pollution than the conventional pickling technology using formic acid, sulfuric acid, and sodium chloride. However, the existing salt-free pickling materials, for instance, aromatic sulfonic acids (ASAs), lead to reduced leather quality and the reason behind this phenomenon is unclear. In this study, we explored how ASAs affect the properties of tannedleather. Results showed that typical ASAs, such as 5-sulfosalicylic acid, 1,5-naphthalenedisulfonic acid, and 2-naphthalenesulfonic acid, penetrated cattle hide more slowly compared with formic and sulfuric acids because of their large molecular weight and strong intermolecular interactions with hide collagen. ASAs decreased the positive charge of the pickled hide via interactions with their sulfonic acid groups, resulting in the increased adsorption rate of chrometanning agent to the hide surface. Rapid tanning agent adsorption could impede the deep penetration and uniform distribution of the agent in the ASA-pickled hide. Thus, the properties of wet blues and crust leathers pickled with ASAs are inferior to those of wet blue and crust leather pickled using conventional pickling materials. Our results indicate that a strongly positive charge of the pickled hide is vital to obtaining high-quality leather and provide insights into salt-free pickling materials from a hide surface charge perspective.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"117 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://journals.uc.edu/index.php/JALCA/article/download/5962/4823","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147888593","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Optimization of Dehairing/Fiber Opening using Ammonium Chloride/Dispase by Response Surface Methodology","authors":"Chao Tang, Hui Liu, Yadi Hu, Fang Wang, Keyong Tang, Jide Zhong","doi":"10.34314/jalca.v117i7.5964","DOIUrl":"https://doi.org/10.34314/jalca.v117i7.5964","url":null,"abstract":"A great number of pollutants including sulfides, suspended solids, and ammonia nitrogen compounds are generated by dehairingand fiber opening with the traditional use of sodium sulfide, calcium hydroxide, and ammonium salt. In this work, ammoniumchloride (NH4Cl)/dispase system was used for the dehairing and fiber opening as an alternative of sodium sulfide/lime system tosimplify the beamhouse operations, as well as to ease environmental pollution. It was found that the removing effect of interfibrillar substance is highly related to the factors such as enzyme catalysis time, temperature and the salt usage. Therefore, the mathematical models of enzyme activity, protein content, polysaccharide content and hydroxyproline content were established by response surface methodology (RSM) with the enzyme catalysis time, temperature and the salt usage as independent variables. It was found that the dehairing/fiber opening effect is the best with 2 % NH4Cl (base onhide weight) at 32.5°C for 15h, and only 3.5 h is needed for dehairing. This work might provide a reference for green leather making with enzymes.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"117 7","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-07-06","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://journals.uc.edu/index.php/JALCA/article/download/5964/4825","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147901202","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Research on the Production of Parchment from Turkey Skin and its Decorative Use","authors":"E. E. Bayramoğlu","doi":"10.34314/jalca.v117i5.4916","DOIUrl":"https://doi.org/10.34314/jalca.v117i5.4916","url":null,"abstract":"In this study, parchment was made of waste turkey skin and some tests were done. These tests were: Determination of thickness (TS 4117 EN ISO 2589), Determination of tensile strength and elongation (TS EN ISO 3376), Determination of tear load - Part 2: (Double edge tear) (TS 4118-2 EN ISO 3377-2), Leather - of distension and strength of grain (TS 4137 EN ISO 3379), Color fastness to water spotting (TS EN ISO 15700). Due to the low strength properties of turkey skin, a different usage area was tried to be created by making a decorative flower design. In this research, it has been tried to show how a waste material can be transformed into a product with a very high added value.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"AES-20 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84584943","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Application of L-Ascorbic Acid as an Antioxidative Colorment in Leather Finishing","authors":"Sultan Çivi, E. E. Bayramoğlu","doi":"10.34314/jalca.v117i5.4909","DOIUrl":"https://doi.org/10.34314/jalca.v117i5.4909","url":null,"abstract":"In this study, chrome tanned bovine crust leathers were dyed white during finishing process. Experiments with 1%, 2%, 3%, 4% and 5% L-ascorbic acid addition were performed on the finishing layer of the finishing application. L-ascorbic acid was not added to the control group and processed according to the standard method. After these processes, color measurement analyzes were performed on Konica Minolta CM 3600d spectrophotometer. In order to investigate the effects of L-ascorbic acid on other performance properties of leather, light fastness test according to TS 1008 EN ISO 105-B02 (2001 TS EN ISO 11640 2001) and dry rub fastness test according to standard method were performed. The results of the study were statistically evaluated according to the NCSS (Number Cruncher Statistical System) method. As a result of the research, it was observed that L-ascorbic acid gave a pearly pink color to the leathers. It was found that the dry rubbing fastness of the leathers treated with L-ascorbic acid improved. In the light fastness tests, the results of the experimental group leathers were recorded better by the blue scale.","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"10 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"74353184","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Silica-Embedded Polyurea Microspheres with Rough Surface for Matte Leather Finishing","authors":"Liang Jia, Li Duo Wang, Jing Li, Jun Xiang, Yi Chen, H. Fan","doi":"10.34314/jalca.v117i5.4913","DOIUrl":"https://doi.org/10.34314/jalca.v117i5.4913","url":null,"abstract":"A type of polyurea microspheres with rough surfaces and different sizes (1-12 μm), which was used for waterborne polyurethane matte leather coating, were prepared by precipitation polymerization in H 2 O/acetonitrile system, using isophorone diisocyanate as polymerized monomer, 2,4-diaminobenzenesulfonic acid sodium salt as hydrophilic monomer and nano-SiO 2 as surface roughener. The effect of the loading of isophorone diisocyanate and 2,4-diaminobenzenesulfonic acid sodium salt, the volume ratio of H 2 O/acetonitrile and the addition stage of nano-SiO 2 on the particle size and surface roughness were investigated so as to achieve the excellent matte effect of the coating. The results indicated that the adding of hydrophilic monomer can reduce the particle size of microspheres and improve its re-dispersibility in water, while the increase of the proportion of acetonitrile in the mixed solvent and the loading of polymerized monomer can enlarge the size of the polyurea microspheres. As surface roughener, with the increase of nano-SiO 2 loading, the surface roughness and the particle size of microspheres increase. When nano-SiO 2 is added at the stage of the reaction system getting turbid, the maximum surface roughness of polyurea microspheres can be achieved. Polyurea microspheres with particle size (1-2 μm) and high surface roughness have better matting effect, and the gloss of the prepared waterborne polyurethane coating can be adjusted to less than 1.6° (60°-incident Angle).","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"308 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85719603","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"ACLA Spring Council Meeting Minutes","authors":"Jalca Editor","doi":"10.34314/jalca.v117i5.4923","DOIUrl":"https://doi.org/10.34314/jalca.v117i5.4923","url":null,"abstract":"ACLA Spring Council Meeting Minutes","PeriodicalId":17201,"journal":{"name":"Journal of The American Leather Chemists Association","volume":"22 1","pages":""},"PeriodicalIF":0.9,"publicationDate":"2022-04-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81790832","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"工程技术","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}