Dépouillements

Combined organic tanning based on mimosa and oxazolidine : development of a semi-industrial scale process for high-quality bovine upper leather / A. d'aquino in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 2 (03-04/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 2 (03-04/2004) . - p. 47-55 Titre : Combined organic tanning based on mimosa and oxazolidine : development of a semi-industrial scale process for high-quality bovine upper leather Type de document : texte imprimé Auteurs : A. d'aquino, Auteur ; N. Barbani, Auteur ; G. d'Elia, Auteur ; D. Lupinacci, Auteur ; Biagio Naviglio, Auteur ; Maurizia Seggiani, Auteur Année de publication : 2004 Article en page(s) : p. 47-55 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Caractérisation Cuirs et peaux de bovins Mimosa et constituants Oxazolidine Réticulants Tannage combiné Le tannage combiné se dit des tannages qui allient deux familles ou genre de tannage pour obtenir un résultat additionnant les qualités complémentaires des tannins mis en œuvre par exemple Chrome-Végétal ou Chrome-Synthétique Tannage organique Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : In this study we present an industrial-scaled tanning process intended to replace chrome tanning in the production of high quality bovine shoe upper leathers using a combined tannage based on a mimosa and oxazolidine as crosslinking agent. This paper reports the best recipe developed and the properties of the leather obtained. The various test results and scanning electron microscopy (SEM) observations which were used as investigative methods to follow the tanning process steps and to better understand the cross-linking mechanisms, are detailed together with the characterisation of the effluents. The leather obtained is characterised by a good hydrothermal stability coupled with good physical and technical properties which allow it to easily comply with the standards required for high quality chromium-tanned bovine upper leather. The results obtained suggest that this tannage is a promising alternative to traditional chrome tanning. Note de contenu : - Interactions between the collagen structure, mimosa, and oxazolidine - Laboratory scale investigation - Semi-industrial scale investigation and properties of the crust leather - SEM analysis - Characterization of the exhaust bath of the mimosaoxazolidine tannage - Table 1 : Pre-tanning and tanning agents used - Table 2 : Steps of fatliquoring/dyeing process (offers: wt.% based on tanned weight) - Table 3 : Steps of the Mimosa-Oxazolidine tanning process - Table 4 : Steps of the Oxazolidine-Mimosa tanning process - Table 5 : Pollutants in the exhaust bath of the mimosa-oxazolidine tannage compared with a typical chromium exhaust bath En ligne : https://drive.google.com/file/d/18RDaXSoVzI-3FZsq97w_hp0jR9_xLdOu/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39641 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Extension and recovery of cervine garment leather / S. E. Gore in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 2 (03-04/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 2 (03-04/2004) . - p. 56-62 Titre : Extension and recovery of cervine garment leather Type de document : texte imprimé Auteurs : S. E. Gore, Auteur ; R. M. Laing, Auteur ; D. J. Carr, Auteur ; B. E. Niven, Auteur Année de publication : 2004 Article en page(s) : p. 56-62 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Propriétés mécaniques Cuirs et peaux de cervidés Statistique Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The objective of this study was to examine the extension and recovery behaviour of cervine garment leather. Cervine leather was more extensible than both ovine leather and conventional woven textiles for outerwear. The load and work required for a given extension decreased and stiffness increased during uniaxial and multiaxial extension/recovery cycling. The number of cycles and the extension level affected load, work and stiffness of the first four cycles only (in particular the first cycle). The number of cycles, the direction, and the level of extension did not greatly affect recovery, most of which occurred within 24 hours. For a given extension, the load, work, and stiffness were greater for specimens cut at 0° to the approximate backbone line than those cut at 90°. All differences attributable to direction were small, sometimes not statistically significant, and thus unlikely to affect garment manufacture, or wear. The minimal observed changes after extended periods of uniaxial cyclic testing suggests cervine leather to be a reasonably stable material. Note de contenu : - EXPERIMENTAL METHODS : Source of leather - Experimental design and procedures - Data collection and statistical analysis - RESULTS : Extension/recovery cycling and rate of change - Slopes - Work - Recovery - Appearance - DISCUSSION : Experimental methods - Cervine leather as a garment material - - Table 1 : Significance of differences in variables En ligne : https://drive.google.com/file/d/19cFg-wQVLnzV0BJXXtMuMMiheQkn-YGk/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39642 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Determination of water vapour permeability of leather / Hans-Jürgen Kellert in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 2 (03-04/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 2 (03-04/2004) . - p. 63-65 Titre : Determination of water vapour permeability of leather : A report of the VGCT commission for leather testing and evaluation Type de document : texte imprimé Auteurs : Hans-Jürgen Kellert, Auteur Année de publication : 2004 Article en page(s) : p. 63-65 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Croûte (cuir) On entend par "cuir en croûte" des cuirs ayant subi les opérations jusqu'au tannage, à l'exclusion de toute opération de corroyage ou de finissage, mais qui, par opposition aux wet-blue ont été séchés. Cuir Cuir dans les automobiles Cuirs et peaux -- Analyse Perméabilité Vapeur d'eau Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : This is the first report of an irregular series providing information on the performance capability of test methods used for many years in the leather industry. The reason and purpose of the series is to provide the reader with an impression of the range and variability of the measured values which result from the use of the test methods on leather. Anyone concerned with the testing of leather over a period of time will be aware of the problem of agreement of results between two testers. Despite sampling according to DIN, the results agree only to a limited extent. Reasons for this come readily to mind, there is the variability of the leather itself or, the actual location of the specimen may not be known. As a rule these differences are not understood by the customer. In customer specifications the requirements are often stated in the form of “greater than”, “less than” or as a range “from...to”. These do not provide a problem provided that the achieved values are markedly in excess or below the stipulated values and within the confidence limits of the test method. Problems can arise however when the average value for the delivery conforms to the requirement but is close to the defined limit. It is then possible for individual results to be outside the required values. A recheck by the customer may indicate a failure whereas the producer had achieved compliance in his tests. In order to avoid the possibility of rejection or claims for compensation, it is of considerable importance to know the likely deviations of the test method used. The determination of water vapour permeability according to DIN 53333 is one of those test methods where considerable differences in the determined values can occur. Not only are these variations due to the leather but also to the method itself and the interpretation of the method details. In order to determine the variability of the test method, a round robin test is ideal as unrelated practitioners test a common material by the same method. The resultant standard deviations of the average values provide a good means of characterising the test method. Disadvantages of this approach are the large amount of material required, as sampling is from the official sampling position and the rapidly increasing number of samples required with an increase in the number of participants. Note de contenu : - Table 1 : Water vapour permeability values for the FOC crust leather - Table 2 : Water vapour permeability values of the finished FOC leather En ligne : https://drive.google.com/file/d/1hvOjwJtXbm18sj0NjLS0T885yV28PfL7/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39643 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Physiological and cell biological properties in vitro of collagen isolated from calf limed splits / G. I. Ly in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 2 (03-04/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 2 (03-04/2004) . - p. 66-71 Titre : Physiological and cell biological properties in vitro of collagen isolated from calf limed splits Type de document : texte imprimé Auteurs : G. I. Ly, Auteur ; Shigeharu Fukunaga, Auteur ; K. Takenouchi, Auteur ; F. Nakamura, Auteur Année de publication : 2004 Article en page(s) : p. 66-71 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cellules -- Adhésivité Cellules -- Prolifération Collagénases Les collagénases sont des enzymes capables de rompre les liaisons peptidiques du collagène. Elles facilitent la destruction des structures extracellulaires lors de la pathogenèse bactérienne. Ce sont des exotoxines. La production de collagénases peut être induite lors d'une réponse immunitaire, par les cytokines qui stimulent les cellules telles que les fibroblastes et les ostéoplastes et occasionnent indirectement des lésions tissulaires. Collagène -- Analyse Collagène -- Solubilité Cuirs et peaux de veaux Fibrilles de collagène La fibrille de collagène est une structure constituée d'un assemblage de fibres de tropocollagène (assemblage de 3 protéines de collagène alpha (alpha 1 - alpha 1 - alpha 2) en une hélice droite. Kératinocytes Les kératinocytes sont des cellules constituant 90 % de la couche superficielle de la peau (épiderme) et des phanères (ongles, cheveux, poils, plumes, écailles). Ils synthétisent la kératine (kératinisation), une protéine fibreuse et insoluble dans l'eau, qui assure à la peau sa propriété d'imperméabilité et de protection extérieure. L'épiderme est divisé en 4 couches basées sur la morphologie des kératinocytes (de l'intérieur vers l'extérieur) : 1. stratum germinativum (couche basale à la jonction avec le derme) 2. stratum spinosum 3. stratum granulosum 4. stratum lucidum 5. stratum corneum Les kératinocytes passent progressivement de la couche basale vers les couches supérieures par différenciation cellulaire jusqu'au stratum corneum ou ils forment une couche de cellules mortes nommées squames, par apoptose. Cette couche constitue une barrière de protection et réduit la perte d'eau de l'organisme. Les kératinocytes sont en perpétuel renouvellement. Ils mettent environ 1 mois pour aller de la couche basale au stratum corneum mais ce processus peut être accéléré en cas d'hyperprolifération de kératinocyte (psoriasis). Systèmes auto-assemblés Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Experiments on self-assembly, susceptibility to collagenase degradation and activity for cell adhesion were carried out to determine the differences between collagen isolated from calf limed splits with acetic acid, alkali or pepsin treatment and commercial type I collagen produced from fresh bovine skins with acetic acid. Self-assembly was observed in all collagen solutions; however, fibril formation of acetic acid-treated collagen and pepsin-treated collagen was observed at neutral pH, as was that of commercial type I collagen whereas, alkali-treated collagen lost its ability of assembly at neutral pH but was able to form fibrils under acidic conditions. Scanning electron microscopy showed that the assembled fibrils from acetic acid-treated collagen had a major fibrous and minor membranous structure similar to that of commercial type I collagen but that reconstructed fibrils from pepsin-treated collagen were more rectilinear and evenly dispersed than were those of other collagens. Analysis by sodium dodecyl sulphatepolyacrylamide gel electrophoresis revealed that matrix metalloproteinase (MMP-1) cleaved collagen isolated from limed splits at a similar locus to that of commercial type I collagen. Keratinocytes cultured on collagen showed increased rates of attachment and proliferation. Moreover, pepsin-treated collagen had more significant effects on cell attachment and proliferation than commercial acetic acid-extracted type I collagen. Note de contenu : - EXPERIMENTAL METHODS : Preparation of limed splits and solubilized collagen - Collagen fibril formation - Scanning electron microscopy - Collagen digestion with collagenase - Isolation and culture of keratinocytes - Cell adhesive assay - Cell viability and proliferation assay - RESULTS AND DISCUSSION : Collagen self-assembly - Susceptibility to MMP-1 collagenase digestion - Cell adhesion to collagen En ligne : https://drive.google.com/file/d/1oyUIZqFKFf7bHK5bSlsnMk8zFL2wJeYM/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39644 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Combination tannage of tannic acid and rare earth / Shan Zhihua in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 2 (03-04/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 2 (03-04/2004) . - p. 72-75 Titre : Combination tannage of tannic acid and rare earth Type de document : texte imprimé Auteurs : Shan Zhihua, Auteur ; Wang guowei, Auteur Année de publication : 2004 Article en page(s) : p. 72-75 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Poudre de peaux Tanins végétaux Tannage combiné Le tannage combiné se dit des tannages qui allient deux familles ou genre de tannage pour obtenir un résultat additionnant les qualités complémentaires des tannins mis en œuvre par exemple Chrome-Végétal ou Chrome-Synthétique Tannage minéral Tannage dans lequel interviennent différents minéraux. Le plus répandu est le tannage aux sels de chrome, mais aussi à l’aluminium Tannage végétal Terres rares Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The mechanism of the combination tannage of a rare earth (Ce) bound with tannic acid is described in the paper. Based on the potentiometric titration in aqueous solution of Ce, Gallic acid (Ga) and Glycyl Glycine (GG), we found that that the formation constant of the complex CeGa increased with increasing temp, from 9°C to 30°C, lgkCeGa rose from 11.55 to 11.92, while the formation constant of complex CeGG decreased with increasing temperature, from 6.35 to 3.08. Complex CeGa and mixed ligand complexes CeGaGG in the solid state display a stronger resistance to thermal decomposition than uncombined CeCl3, Ga and GG. When reacting Ce(III) and tannic acid with hide powder or modified hide powder either together or separately, it was found that Ce coordinated on tannins, while tannic acid combined with collagen, and this manner of combination played a important role in the combination tannage. Based on these studies, the paper proposed the concept “Poly--Strut Firm Structure” to explain the synergistic effect in rare earth-vegetable tannins combination tannage. Note de contenu : - EXPERIMENTAL PROCEDURE : Chemicals and instruments - Stability of rare earth complexes - RE action with hide powder or modified hide powder - RE+T action with hide powder or modified hide powder - RE+T action with other groups of protein - RESULTS : The stability of RE complexes - RE action on hide powders or modified hide powders - RE and T action on hide powders or modified hide powders - RE+T action on substitutes - DISCUSSIONS : Ts as the judgment of tanning effect - The concept of tanning power of tanning agents - Poly-strut firm structure deduction - Table 1 : Formation constants of CEGa, CeGG, CeGaGG at different temperatures - Table 2 : Weight loss values of CeGa, CeGG, CeGaGG (Rate : 20°C./min, at 300°C) - Table 3 : Reaction of RE with hide powders (based on hide powder weight) - Table 4 : RE+T action on hide powder sor modified hide powders - Table 5 : RE bonded with substitutes (based on substitutes weight En ligne : https://drive.google.com/file/d/1da0QhJ0FNoXVBxQHcxkOILrjfQji9zzW/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39645 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire

Combination of white minerals with natural tannins : chrome-free tannage for garment leathers / Subramanian Saravanabhavan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 88, N° 2 (03-04/2004)  

[article]  inJOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 88, N° 2 (03-04/2004) . - p. 76-81 Titre : Combination of white minerals with natural tannins : chrome-free tannage for garment leathers Type de document : texte imprimé Auteurs : Subramanian Saravanabhavan, Auteur ; N. N. Fathima, Auteur ; J. R. Rao, Auteur ; B. U. Nair, Auteur Année de publication : 2004 Article en page(s) : p. 76-81 Note générale : Bibliogr. Langues : Anglais (eng) Catégories : Cuirs et peaux -- Propriétés physiques Liqueurs de tannage -- Analyse Silice La silice est la forme naturelle du dioxyde de silicium (SiO2) qui entre dans la composition de nombreux minéraux. La silice existe à l'état libre sous différentes formes cristallines ou amorphes et à l'état combiné dans les silicates, les groupes SiO2 étant alors liés à d'autres atomes (Al : Aluminium, Fe : Fer, Mg : Magnésium, Ca : Calcium, Na : Sodium, K : Potassium...). Les silicates sont les constituants principaux du manteau et de l'écorce terrestre. La silice libre est également très abondante dans la nature, sous forme de quartz, de calcédoine et de terre de diatomée. La silice représente 60,6 % de la masse de la croûte terrestre continentale. Tanins Tannage minéral Tannage dans lequel interviennent différents minéraux. Le plus répandu est le tannage aux sels de chrome, mais aussi à l’aluminium Température de retrait Zinc Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : There is a growing need for eco-benign tanning systems owing to stringent environmental regulations. In this present study, a new combination tanning system using zinc, tannic acid and silica has been explored for the manufacture of garment leathers. The amounts of zinc, tannic acid and silica used have been optimised as 10, 10 and 5% respectively. The shrinkage temperature of the leathers obtained is 85°C. The impact of this tanning system on the environment has been assessed by analysing the effluent liquor for zinc, sulphate, BOD, COD and TDS. A significant reduction in BOD, COD and TDS loads has been achieved and the exhaustion of zinc is about 90%. The organoleptic and the strength properties of the garment leathers made using this combination system are generally comparable to those of conventional chrome tanned leather. Note de contenu : - EXPERIMENTAL METHODS : Materials - Optimization of the amount of zinc, tannic acid and silica for pickle-less tanning - TANNING TRIALS : Physical examination - Analysis of spent tan liquor - Scanning Electron Microscopic examination - RESULTS AND DISCUSSION : Optimization of zinc, tannic acid and silicate for pickle-less tanning - ECO-BENIGN IMPACT - Table 1 : Optimization of tannic acid - Table 2 : Optimization of zinc sulphate with and without 10% tannic acid - Table 3 : Shrinkage temperature of leathers tanned using zinc sulphate (10%), tannic acid (10%) with varying amount of sodium metasilicate - Table 4 : Shrinkage temperature of leathers tanned using sodium metasilicate (5%), tannic acid (10%) with varying amount of zinc sulphate - Table 5 : Shrinkage temperature of leathers tanned using sodium metasilicate (5%), zinc sulphate (10%) with varying amount of tannic acid - Table 6 : Physical testing data of control (C) and experimental (E) leathers - Table 7 : Characteristics of spent tan liquor En ligne : https://drive.google.com/file/d/1tbULNTNE_NwX8bvsqtGw7SPm7W0fS3ZM/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=39646 [article]

Exemplaires

Code-barres	Cote	Support	Localisation	Section	Disponibilité
aucun exemplaire