Bating is one of the important stages in the tanning process that has a role as a determinant of leather properties. It is commonly carried out with the assistance of protease enzymes such as papain. By using surfactants, sorbitol and Sodium Dodecyl Sulfate (SDS), it can help the penetration of enzymes into the skin or hides. Thereby, the study aimed to evaluate the use of papain on the bating process of kacang goat skin by assisted surfactants. Accordingly, three different concentrations (1, 1.5, & 2%) of enzymes were added with two different types of surfactants (SDS and Sorbitol) for the bating process. For the result, the leather was evaluated based on physical properties and histology studies. The presence of surfactant in the bating process improves the absorption of papain towards the hydrolysis of non-collagenous proteins. Based on the physical properties and histology studies, they perform better than leather without surfactant agents. Cleary, the surfactant agents can be used as bating auxiliary.
{"title":"Evaluation of Physical Properties of Leather on the Bating Process by Combination of Papain Enzyme with Surfactant","authors":"M. Z. Abidin, R. Yuliatmo, G. Griyanitasari","doi":"10.24264/lfj.22.2.3","DOIUrl":"https://doi.org/10.24264/lfj.22.2.3","url":null,"abstract":"Bating is one of the important stages in the tanning process that has a role as a determinant of leather properties. It is commonly carried out with the assistance of protease enzymes such as papain. By using surfactants, sorbitol and Sodium Dodecyl Sulfate (SDS), it can help the penetration of enzymes into the skin or hides. Thereby, the study aimed to evaluate the use of papain on the bating process of kacang goat skin by assisted surfactants. Accordingly, three different concentrations (1, 1.5, & 2%) of enzymes were added with two different types of surfactants (SDS and Sorbitol) for the bating process. For the result, the leather was evaluated based on physical properties and histology studies. The presence of surfactant in the bating process improves the absorption of papain towards the hydrolysis of non-collagenous proteins. Based on the physical properties and histology studies, they perform better than leather without surfactant agents. Cleary, the surfactant agents can be used as bating auxiliary.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41582823","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Leather products are affected by the quality of the raw hide, the pre-treatment, and the tanning process. Furthermore, some leather products use quality goatskins with the right determination as raw materials. This study aims to determine the quality of goatskin through the use of Fuzzy Logic science. It was conducted using the Sugeno Fuzzy Inference System (FIS), while data analysis was carried out through the Matlab R2018a program. The criteria for using this method were the factors that affected the quality of raw goatskin such as thickness, length of the backline, skin area, number of scratches on the skin, number of holes, presence of boils, lice bumps, and hair loss. The results of the analysis showed that Sugeno FIS could be used to help determine the quality of goatskin with a good accuracy level with a MAPE value of 18%. Furthermore, the FIS method could be used as an appropriate modeling system for determining the quality of goatskin as a raw material for the leather tanning industry.
{"title":"The Use of the Fuzzy Inference System in Determining the Quality of Goatskin as Raw Material for the Leather Industry","authors":"S. Mutiar, A. Kasim, E. Emriadi, A. Asben","doi":"10.24264/lfj.22.2.4","DOIUrl":"https://doi.org/10.24264/lfj.22.2.4","url":null,"abstract":"Leather products are affected by the quality of the raw hide, the pre-treatment, and the tanning process. Furthermore, some leather products use quality goatskins with the right determination as raw materials. This study aims to determine the quality of goatskin through the use of Fuzzy Logic science. It was conducted using the Sugeno Fuzzy Inference System (FIS), while data analysis was carried out through the Matlab R2018a program. The criteria for using this method were the factors that affected the quality of raw goatskin such as thickness, length of the backline, skin area, number of scratches on the skin, number of holes, presence of boils, lice bumps, and hair loss. The results of the analysis showed that Sugeno FIS could be used to help determine the quality of goatskin with a good accuracy level with a MAPE value of 18%. Furthermore, the FIS method could be used as an appropriate modeling system for determining the quality of goatskin as a raw material for the leather tanning industry.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43071450","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Adhesives based on collagen extracted from the skin, tendons, cartilage, bones of animals and fish have been widely used over time as binders and consolidating agents for various organic and inorganic materials. The use of these types of adhesives or glues or gelatins in the restoration activity has been practiced by restorers due to their properties, but also to the special requirements of reversibility of treatments that are stipulated in national and international norms specific to the restoration of heritage objects. For this purpose, the technology of gelatin extraction from bovine hide was studied, and then gelatins were characterized in terms of chemical properties (ash, total nitrogen, amino nitrogen, dermal substance, pH of analytical solution) and gluing experiments were conducted on collagen substrates (leather and parchment, newly made specifically for the restoration activity and some samples of historical parchment, pieces of parchment detached from the back of a heritage object) and characterized in terms of physical-mechanical properties (shear strength and peel strength). Gelatins made from bovine hide were also compared to a commercial product, rabbit glue, a material frequently used in the field of restoration.
{"title":"Preliminary Study on the Adhesiveness Properties of Hide Glue","authors":"L. Miu, M. Niculescu","doi":"10.24264/lfj.22.2.7","DOIUrl":"https://doi.org/10.24264/lfj.22.2.7","url":null,"abstract":"Adhesives based on collagen extracted from the skin, tendons, cartilage, bones of animals and fish have been widely used over time as binders and consolidating agents for various organic and inorganic materials. The use of these types of adhesives or glues or gelatins in the restoration activity has been practiced by restorers due to their properties, but also to the special requirements of reversibility of treatments that are stipulated in national and international norms specific to the restoration of heritage objects. For this purpose, the technology of gelatin extraction from bovine hide was studied, and then gelatins were characterized in terms of chemical properties (ash, total nitrogen, amino nitrogen, dermal substance, pH of analytical solution) and gluing experiments were conducted on collagen substrates (leather and parchment, newly made specifically for the restoration activity and some samples of historical parchment, pieces of parchment detached from the back of a heritage object) and characterized in terms of physical-mechanical properties (shear strength and peel strength). Gelatins made from bovine hide were also compared to a commercial product, rabbit glue, a material frequently used in the field of restoration.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41569576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This work is intended to reveal the most important physico-chemical and physico-mechanical characteristics of the fur skins that determine their quality. Values of these characteristics are discussed as depending on the semifinished product related to technological significance and consequence for the user. The main characteristics and values for fine furs are proposed, thus providing some guidelines in evaluating their quality. Investigations in this field can lead to the determination of some new quality characteristics of woolen sheepskins and fine furs. A case study on fine and common furskins is presented and reveals the uniqueness and versatility of the combination of two protein layers, represented by natural furs, composed of collagen and keratin, unmatched by any synthetic material.
{"title":"Fur Skin – A Valuable Material, Considerations on Quality Assessment","authors":"C. Gaidău, Elisavet Amanatidou, Stoica Tonea","doi":"10.24264/lfj.22.2.5","DOIUrl":"https://doi.org/10.24264/lfj.22.2.5","url":null,"abstract":"This work is intended to reveal the most important physico-chemical and physico-mechanical characteristics of the fur skins that determine their quality. Values of these characteristics are discussed as depending on the semifinished product related to technological significance and consequence for the user. The main characteristics and values for fine furs are proposed, thus providing some guidelines in evaluating their quality. Investigations in this field can lead to the determination of some new quality characteristics of woolen sheepskins and fine furs. A case study on fine and common furskins is presented and reveals the uniqueness and versatility of the combination of two protein layers, represented by natural furs, composed of collagen and keratin, unmatched by any synthetic material.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41425830","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
This paper presents the method and results of developing a shoe last sizing system on the basis of the foot parameter system, designing shoe lasts for men with diabetes in Vietnam. Diabetic patients often have foot complications and need to use extra depth shoes or custom shoes to protect their feet and prevent foot ulcers. The parameters of 5 shoe last sizes by length and 3 sizes by width according to the French sizing system have been developed. The results show that the shoe last parameters for men with diabetes are much larger than those for healthy men, especially the ball girth and width are larger by about 20 mm and 5 mm, respectively. Afterward, shoe lasts were designed and modified using 3D CAD tools for style, fit and comfort specifically suited for men with diabetes. Using shoe last design software, 3D printing technology to design and fabricate a shoe last, the proposed approach proved the viability of designing and manufacturing extra depth shoes for men with diabetes in Vietnam.
{"title":"Research on Developing a Size System and Designing Shoe Lasts for Men with Diabetes in Vietnam","authors":"Van-Huan Bui, Thi-Kien-Chung Cao, Duy-Nam Phan","doi":"10.24264/lfj.22.2.1","DOIUrl":"https://doi.org/10.24264/lfj.22.2.1","url":null,"abstract":"This paper presents the method and results of developing a shoe last sizing system on the basis of the foot parameter system, designing shoe lasts for men with diabetes in Vietnam. Diabetic patients often have foot complications and need to use extra depth shoes or custom shoes to protect their feet and prevent foot ulcers. The parameters of 5 shoe last sizes by length and 3 sizes by width according to the French sizing system have been developed. The results show that the shoe last parameters for men with diabetes are much larger than those for healthy men, especially the ball girth and width are larger by about 20 mm and 5 mm, respectively. Afterward, shoe lasts were designed and modified using 3D CAD tools for style, fit and comfort specifically suited for men with diabetes. Using shoe last design software, 3D printing technology to design and fabricate a shoe last, the proposed approach proved the viability of designing and manufacturing extra depth shoes for men with diabetes in Vietnam.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43542786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Designing and manufacturing personalized lasts are the first steps in obtaining the right fitted footwear for various users, especially for sports or/and medical purposes. The accurate dimensional relationship between foot and last represents the key element for this activity. The critical shape of the last should always be determined by the shape of the foot and the cumulative relationship between lengths, widths, heights and girths, whatever method is used. Some corrections and constraints must always be considered because the shoe-last is not identical to the foot. The foot anthropometric measurements are modified based on biomechanical constraints and technological limitations and they are interactively transformed into last’s dimensions by using 3D modelling. The present study brings together the modern scanning technique with the new methodology for modifying a reference last, and it is aimed to explore the philosophy of re-designing functional lasts. It also tests and highlights the limits of the actual methodology for shoe-last virtual prototyping based on anthropometric data acquired from a commercially available 3D foot scanning system.
{"title":"3D Modelling of Customized Lasts Based on Anthropometric Data Acquired from 3D Foot Scanning – One Case Study","authors":"Maria Costea, A. Mihai, A. Seul","doi":"10.24264/lfj.22.2.2","DOIUrl":"https://doi.org/10.24264/lfj.22.2.2","url":null,"abstract":"Designing and manufacturing personalized lasts are the first steps in obtaining the right fitted footwear for various users, especially for sports or/and medical purposes. The accurate dimensional relationship between foot and last represents the key element for this activity. The critical shape of the last should always be determined by the shape of the foot and the cumulative relationship between lengths, widths, heights and girths, whatever method is used. Some corrections and constraints must always be considered because the shoe-last is not identical to the foot. The foot anthropometric measurements are modified based on biomechanical constraints and technological limitations and they are interactively transformed into last’s dimensions by using 3D modelling. The present study brings together the modern scanning technique with the new methodology for modifying a reference last, and it is aimed to explore the philosophy of re-designing functional lasts. It also tests and highlights the limits of the actual methodology for shoe-last virtual prototyping based on anthropometric data acquired from a commercially available 3D foot scanning system.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41982404","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
A. Nugraha, O. Suparno, N. S. Indrasti, H. Hoerudin
Enzyme is one of the ingredients used in several tanning processes such as bating. Bating is generally conducted under alkaline conditions, but it can also be carried out under acidic conditions. This study aimed to evaluate mechanical and physical properties of wet blue following bating conducted under acidic conditions treated with enzymes synthesized by R. oligosporus compared to those of the conventional process. This study was arranged on a completely randomized design with a single factor, i.e., five levels of enzyme activity (0, 2.5, 5, 7.5, and 10 U mL-1). The results showed that the use of enzymes from R. oligosporus influenced positively mechanical properties of the wet blue produced. Increasing levels of enzyme activity produced significantly higher tear strength and lower elongation at break values. No significant differences in tensile strength were observed following applications of both the synthesized and conventional enzymes. The synthesized enzyme was best applied at an activity level of 5 U mL-1 producing leather with good tear strength (55.40 ± 5.49 N mm-1) and elongation at break (45.63 ± 4.17 %) values, which were significantly different from those of 0 U mL-1, but not significantly different from those of 10 U mL-1 and the conventional process. Mechanical properties of the leather produced met the standard values for goat/sheep leather jacket as specified in Indonesian National Standard (SNI) 4593:2011. The results suggest that the synthesized enzyme from R. oligosporus can potentially replace the conventional enzyme commonly used in the bating process.
酶是几种制革工艺中使用的成分之一,如蜡染。击球通常在碱性条件下进行,但也可以在酸性条件下进行。本研究旨在评估在酸性条件下用寡孢R.oligosporus合成的酶处理蜡染后的湿蓝与传统工艺相比的机械和物理性能。本研究采用完全随机设计,采用单一因素,即五个酶活性水平(0、2.5、5、7.5和10 U mL-1)。结果表明,寡孢R.oligosporus酶的使用对所生产的湿蓝的机械性能产生了积极影响。酶活性水平的增加产生显著更高的撕裂强度和更低的断裂伸长率。在应用合成酶和常规酶之后,没有观察到拉伸强度的显著差异。合成的酶在5 U mL-1的活性水平下应用效果最好,可生产出具有良好撕裂强度(55.40±5.49 N mm-1)和断裂伸长率(45.63±4.17%)的皮革,与0 U mL-1有显著差异,但与10 U mL-1和常规工艺无显著差异。生产的皮革的机械性能符合印度尼西亚国家标准(SNI)4593:2011中规定的山羊/绵羊皮夹克的标准值。结果表明,由寡孢R.oligosporus合成的酶有可能取代蜡染过程中常用的传统酶。
{"title":"Mechanical Properties of Wet Blue Following Acid Bating Process Treated with Crude Enzyme from Rhizopus oligosporus","authors":"A. Nugraha, O. Suparno, N. S. Indrasti, H. Hoerudin","doi":"10.24264/lfj.22.2.6","DOIUrl":"https://doi.org/10.24264/lfj.22.2.6","url":null,"abstract":"Enzyme is one of the ingredients used in several tanning processes such as bating. Bating is generally conducted under alkaline conditions, but it can also be carried out under acidic conditions. This study aimed to evaluate mechanical and physical properties of wet blue following bating conducted under acidic conditions treated with enzymes synthesized by R. oligosporus compared to those of the conventional process. This study was arranged on a completely randomized design with a single factor, i.e., five levels of enzyme activity (0, 2.5, 5, 7.5, and 10 U mL-1). The results showed that the use of enzymes from R. oligosporus influenced positively mechanical properties of the wet blue produced. Increasing levels of enzyme activity produced significantly higher tear strength and lower elongation at break values. No significant differences in tensile strength were observed following applications of both the synthesized and conventional enzymes. The synthesized enzyme was best applied at an activity level of 5 U mL-1 producing leather with good tear strength (55.40 ± 5.49 N mm-1) and elongation at break (45.63 ± 4.17 %) values, which were significantly different from those of 0 U mL-1, but not significantly different from those of 10 U mL-1 and the conventional process. Mechanical properties of the leather produced met the standard values for goat/sheep leather jacket as specified in Indonesian National Standard (SNI) 4593:2011. The results suggest that the synthesized enzyme from R. oligosporus can potentially replace the conventional enzyme commonly used in the bating process.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-06-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"43371577","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
M. Nițuică, M. Stelescu, M. Sönmez, L. Alexandrescu, M. Georgescu, D. Gurau, Mirela Pantazi-Băjenaru
Waste is a material that occurs as a result of a biological or technological process that can no longer be used as such. Recycling and reusing waste make it possible to contribute to environmental protection and, of course, to the protection of human health by eliminating toxins during waste incineration. The purpose of this paper is to process and characterize polymer composites based on NBR rubber (butadiene-co-acrylonitrile rubber) and rubber waste functionalized with potassium oleate in terms of rheological characteristics (to determine the optimal vulcanization time), Brabender diagrams and physico-mechanical properties in normal state and after accelerated ageing at 70°C, for 168 h (using elastomer-specific equipment). Functionalized rubber waste (with potassium oleate up to 20% at 60°C) is introduced into the mixture in proportions of 10; 20; 30; 50%. The polymeric composites based on butadiene-co-acrylonitrile elastomer and rubber waste (ground with a cryogenic mill at 10,000 rpm, at the size of 0.35 mm) were compounded on a mixer with a capacity of 350 cm3 according to the working recipes. The mixtures were supplemented with vulcanization activators and accelerators on an electric roller, resulting in formulations in the form of 4 mm thick sheets, which are then subjected to the relevant characterizations according to the standards in force for the footwear industry.
{"title":"Polymer composite based on NBR rubber compounded with rubber waste functionalized with potassium oleate","authors":"M. Nițuică, M. Stelescu, M. Sönmez, L. Alexandrescu, M. Georgescu, D. Gurau, Mirela Pantazi-Băjenaru","doi":"10.24264/lfj.22.1.5","DOIUrl":"https://doi.org/10.24264/lfj.22.1.5","url":null,"abstract":"Waste is a material that occurs as a result of a biological or technological process that can no longer be used as such. Recycling and reusing waste make it possible to contribute to environmental protection and, of course, to the protection of human health by eliminating toxins during waste incineration. The purpose of this paper is to process and characterize polymer composites based on NBR rubber (butadiene-co-acrylonitrile rubber) and rubber waste functionalized with potassium oleate in terms of rheological characteristics (to determine the optimal vulcanization time), Brabender diagrams and physico-mechanical properties in normal state and after accelerated ageing at 70°C, for 168 h (using elastomer-specific equipment). Functionalized rubber waste (with potassium oleate up to 20% at 60°C) is introduced into the mixture in proportions of 10; 20; 30; 50%. The polymeric composites based on butadiene-co-acrylonitrile elastomer and rubber waste (ground with a cryogenic mill at 10,000 rpm, at the size of 0.35 mm) were compounded on a mixer with a capacity of 350 cm3 according to the working recipes. The mixtures were supplemented with vulcanization activators and accelerators on an electric roller, resulting in formulations in the form of 4 mm thick sheets, which are then subjected to the relevant characterizations according to the standards in force for the footwear industry.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"45769158","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
In the leather tanning industry, decision-makers act resolutely to eliminate chrome as a tanning agent due to its negative effect on human health and the natural environment. Considering this, it makes sense to research opportunities to use chrome-free leather as a substitute for chrome-tanned leather. This paper demonstrates research on the mechanical and hygienic properties of leather tanned with glutaraldehyde as well as chrome-tanned leather, intended for shoe uppers. The results of the tensile strength and percentage extension measurements made by the Instron tensile machine, and the results of water vapour permeability measurements made by a moisture analyser, have been analysed using Statistica. The statistical data analysis has been performed using the following tests: Kolmogorov-Smirnov with Lilliefors correction, Shapiro-Wilk, T, Levene, Brown and Forsythe, Fisher-Snedecor, and Cochran-Cox. Regarding mechanical parameters, no statistically significant difference has been observed between chrome-free and chrome-tanned leather in dry conditions. However, such differences have been observed in wet samples. The tests showed higher stability of mechanical parameters of leather tanned with modified glutaraldehyde compared to chrome-tanned leather. Leather tanned with a chrome tanning agent, tested in both dry and wet conditions, showed significant differences between them, considering their tensile strength and percentage extension. The hygienic properties of both types of leather being researched are more or less similar – the research has not found any statistically significant differences for water vapour permeability.
在皮革制革行业,由于铬对人体健康和自然环境的负面影响,决策者坚决采取行动,以消除铬作为制革剂。考虑到这一点,研究使用无铬皮革作为铬鞣皮革的替代品是有意义的。本文对戊二醛鞣革和铬鞣革的机械性能和卫生性能进行了研究。用Instron拉伸机测量拉伸强度和拉伸百分率的结果,以及用水分分析仪测量水蒸气渗透性的结果,用Statistica进行了分析。统计数据分析使用以下检验:Kolmogorov-Smirnov with Lilliefors correction, Shapiro-Wilk, T, Levene, Brown and Forsythe, Fisher-Snedecor和Cochran-Cox。关于机械参数,在干燥条件下,无铬皮革和铬鞣皮革之间没有统计学上的显著差异。然而,这种差异已在湿样品中观察到。试验结果表明,改性戊二醛鞣制皮革的力学参数稳定性优于铬鞣制皮革。用铬鞣剂鞣制的皮革,在干湿两种条件下进行测试,考虑到它们的拉伸强度和伸长率,两者之间存在显着差异。被研究的两种皮革的卫生性能或多或少是相似的——研究没有发现水蒸气渗透性有任何统计学上的显著差异。
{"title":"Comparison and assessment of selected parameters of chrome-free and chrome-tanned leather","authors":"E. Bielak, G. Zielińska","doi":"10.24264/lfj.22.1.1","DOIUrl":"https://doi.org/10.24264/lfj.22.1.1","url":null,"abstract":"In the leather tanning industry, decision-makers act resolutely to eliminate chrome as a tanning agent due to its negative effect on human health and the natural environment. Considering this, it makes sense to research opportunities to use chrome-free leather as a substitute for chrome-tanned leather. This paper demonstrates research on the mechanical and hygienic properties of leather tanned with glutaraldehyde as well as chrome-tanned leather, intended for shoe uppers. The results of the tensile strength and percentage extension measurements made by the Instron tensile machine, and the results of water vapour permeability measurements made by a moisture analyser, have been analysed using Statistica. The statistical data analysis has been performed using the following tests: Kolmogorov-Smirnov with Lilliefors correction, Shapiro-Wilk, T, Levene, Brown and Forsythe, Fisher-Snedecor, and Cochran-Cox. Regarding mechanical parameters, no statistically significant difference has been observed between chrome-free and chrome-tanned leather in dry conditions. However, such differences have been observed in wet samples. The tests showed higher stability of mechanical parameters of leather tanned with modified glutaraldehyde compared to chrome-tanned leather. Leather tanned with a chrome tanning agent, tested in both dry and wet conditions, showed significant differences between them, considering their tensile strength and percentage extension. The hygienic properties of both types of leather being researched are more or less similar – the research has not found any statistically significant differences for water vapour permeability.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"41925436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Nowadays, one of the most critical health problems among young people is obesity. Because teenagers are still in the growing process, the foot shape and plantar footprints are very important to be analysed and potential problems to be identified. Young adulthood is a risky period for the development of obesity. This study aims to analyse the plantar footprints, the biomechanical parameters obtained through plantar pressure measurements, and the 3D shape of the foot and anthropometrical parameters obtained from scanning. By comparing the results, both feet have been demonstrated to be high arched, as well as high pressures were identified and differences from left to the right foot. With these results, prophylactic footwear and components can be designed, adapted to the subject’s feet.
{"title":"Plantar footprints and 3D foot shape digital analysis for overweight teenager – one case study","authors":"Maria Costea, A. Seul, A. Mihai","doi":"10.24264/lfj.22.1.3","DOIUrl":"https://doi.org/10.24264/lfj.22.1.3","url":null,"abstract":"Nowadays, one of the most critical health problems among young people is obesity. Because teenagers are still in the growing process, the foot shape and plantar footprints are very important to be analysed and potential problems to be identified. Young adulthood is a risky period for the development of obesity. This study aims to analyse the plantar footprints, the biomechanical parameters obtained through plantar pressure measurements, and the 3D shape of the foot and anthropometrical parameters obtained from scanning. By comparing the results, both feet have been demonstrated to be high arched, as well as high pressures were identified and differences from left to the right foot. With these results, prophylactic footwear and components can be designed, adapted to the subject’s feet.","PeriodicalId":38857,"journal":{"name":"Leather and Footwear Journal","volume":" ","pages":""},"PeriodicalIF":0.0,"publicationDate":"2022-03-31","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"47445105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}