Dépouillements

A study of yeasts in chrome tanning and processing / Waldo E. Kallenberger in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 7-21 Titre : A study of yeasts in chrome tanning and processing Type de document : texte imprimé Auteurs : Waldo E. Kallenberger, Auteur Année de publication : 1978 Article en page(s) : p. 7-21 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Croissance microbienne 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. Cuirs et peaux Fongicides Levure (Agent de fermentation) Levures (botanique) Microbiologie Tannage au chrome Wet-blue (tannage) Peau tannée au chrome (le chrome donne une couleur bleue) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Yeasts have previously been associated with stains and color imper-fections in blue chrome stocks and finished leathers. In this work several yeasts were isolated from chrome tanned crust leathers, wet blue stock, reducing sugars and syrups, and scrapings from tannery drums. Three of these different yeasts were maintained on dextrose, tartaric acid sup-plemented nutrient agar media for study. The primary objective of the study was to establish concentrations at which various fungicidal agents were effective in controlling the growth of the three yeasts. Mold was also introduced into test cultures with the yeasts in order to arrive at a comparative fungicide concentration effective in controlling their growth. In addition to the primary effect of the fungicide type and concentration on the yeasts, a number of other observations about the yeasts were noted during the course of the study. Through sugar assimi¬lation and fermentation tests, three yeasts were classified into their genera, Rhodotorula, Cladosporium, and Torulopsis. Note de contenu : - EXPERIMENTAL MATERIALS AND METHODS : Sources of organisms - Identification methods - Fungicide test methods - RESULTS OF EXPERIMENTS : Identification of the pink colonies - Identification of black colonies - Identification of white colonies - RESULTS OF THE FUNGICIDE TESTS - Table 1 : Fermentation and assimilation test results - Table 2 : Organism growth and fungicide concentration - Table 3 : Active ingredients and effective concentration of test fungicides En ligne : https://drive.google.com/file/d/1C2R5dgbYzdLrnqj9ujw73PamAMjkZglY/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41142 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Aqueous topcoats for leather / Charles E. Cluthe in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 22-29 Titre : Aqueous topcoats for leather Type de document : texte imprimé Auteurs : Charles E. Cluthe, Auteur ; Fred A. Desiderio, Auteur ; William C. Prentiss, Auteur Année de publication : 1978 Article en page(s) : p. 22-29 Langues : Américain (ame) Catégories : Cuirs et peaux -- Finition Durée de vie (Ingénierie) Formulation (Génie chimique) Polyacryliques Solidité de la couleur Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Raw material shortages, cost escalation, and restrictions on the use of organic solvents (safety and pollution control) have stimulated a demand for all water based finish systems. Aqueous acrylic topcoat products have been developed to replace the traditional nitro-cellulose lacquers and lacquer emulsions in intermediate and final topcoats. Although not identical, the acrylic topcoating products can be easily formulated to yield aesthetic and performance properties comparable to the traditional nitro-cellulose products. Performance factors discussed in comparing the new topcoat with other systems include : Durability Shoe factory ironability Block Resistance tactile aesthetics plateability Color fastness Formulation guidelines including descriptions of and need for auxilliary materials are included. Note de contenu : - Comparison of topcoat materials - Formulations and application parameters - Properties of finished - Table 1 : Ranges of typical property values for products as supplied - Table 2 : Tensile properties of free films - Table 3 : Examples of topcoat formulation (ingredients in percent by weight) - Table 4 : Leather topcoat performance parameters En ligne : https://drive.google.com/file/d/1KA44OvLz0iK62RXtDnOoJ-xarXqC43te/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41143 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

A statistical comparison of synthetic retanning materials / William C. Prentiss in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 30-39 Titre : A statistical comparison of synthetic retanning materials Type de document : texte imprimé Auteurs : William C. Prentiss, Auteur ; Charles R. Sigafoos, Auteur ; H. A. Tetreault, Auteur Année de publication : 1978 Article en page(s) : p. 30-39 Langues : Américain (ame) Catégories : Agents de tannage Essais (technologie) Plan d'expérience Retannage Statistique Syntans Tannage synthétique Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : A number of synthetic retanning materials differing in chemical type are used regularly in leather manufacture, and each imparts its own characteristics to the final leather. Because of the nature of leather manufacture, it is difficult to compare these characteristics on a systematic hasis and to identify the relative magnitude of contribution to leather quality by each of a number of syntans. Using a randomized sampling procedure and a computerized statistical analysis program, such a comparison has been made. Included in the study to be discussed are chmeical type, percent tans applied and temperature of application. Note de contenu : - EXPERIMENTAL : Sampling procedure - Syntan selection - Retan formula - Retan procedure - Experimental design - Tests methods - Statistical procedure - EVALUATION OF DATA : Thickness ratio - Weight ratio - Yield - Grain crack - Elongation at crack - Ball burst - Elongation at ball burst En ligne : https://drive.google.com/file/d/1oGDVdKlR-X6iy2oEAF-Nk43gxOrrmmcU/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41144 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Radiation curing and its potential for leather coatings / Peter R. Buechler in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 56-69 Titre : Radiation curing and its potential for leather coatings Type de document : texte imprimé Auteurs : Peter R. Buechler, Auteur Année de publication : 1978 Article en page(s) : p. 56-69 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Cuirs et peaux -- Finition Revêtements -- Séchage sous rayonnement Revêtements organiques Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : In the last ten years there has heen a strong development of radiation-curable coatings. These coatings consist of low molecular weight polymers dissolved in monomers capable of addition polymerization. When exposed to electron beams or to ultraviolet radiation, the system is converted to a solid crosslinked coating within a fraction of a second. Instead of evaporating like other solvents,the monomers are incorporated into the coating. Hence radiation cured coatings are 100 percent active systems. All of the materials employed are used. There is no waste, no air pollution and hecause the cure rate is so rapid, it makes possible line speeds up to 1,000 feet per minute (1), faster than a conventional coating can be applied hy any existing method. In addition to these general advantages of high speed and low pollution, other advantages particularly applicable to leather are available with radiation curable coatings. These are energy savings, improved leather quality, tougher coatings, probable greater arec yield of product, close control of the depth of polymer impregnation and probable applicahility of impregnation to full grain leathers. These potentialities are discussed in this paper. Note de contenu : - Electron beam curing - Potential advantages of EB curing in leather coatings - Ultraviolet curing - Potential advantages of U.V. curing in leather coatings En ligne : https://drive.google.com/file/d/167nZXLZGDK6gubuwISPi_HgaQrgX5VCe/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41145 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

The practice of pasted leather drying / Thomas E. Greene in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 102-111 Titre : The practice of pasted leather drying Type de document : texte imprimé Auteurs : Thomas E. Greene, Auteur Année de publication : 1978 Article en page(s) : p. 102-111 Langues : Américain (ame) Catégories : Cuir -- Collage Cuir -- Séchage Cuir pleine fleur Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : A practical, non-theoretical presentation of the pasting operation, including best accepted methods and techniques, time and money saving tips, basic trouble shooting in problem areas, and maintenance for the tanner to get the most out of his equipment, his men and his leather, with special emphasis on full grain leathers. Covered are the pasting operation itself, the dryer and associated equipment, and skin washing techniques and machines. Note de contenu : - Pre-wet station - Plate washers - Paste application - Slicking technique - Drying - Trouble shooting - Maintenance En ligne : https://drive.google.com/file/d/1tsCmvKMx30M_pXDuhi09NALr5OBHf_bB/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41146 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Investigations on the chromium-aminoacid complexes / Gheorghe Chirita in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 112-118 Titre : Investigations on the chromium-aminoacid complexes Type de document : texte imprimé Auteurs : Gheorghe Chirita, Auteur ; M. K. Pesheva, Auteur ; A. Chirita, Auteur Année de publication : 1978 Article en page(s) : p. 112-118 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Acides aminés Les acides aminés (ou aminoacides) sont une classe de composés chimiques possédant deux groupes fonctionnels : à la fois un groupe carboxyle –COOH et un groupe amine –NH2. Parmi ceux-ci, les acides α-aminés se définissent par le fait que leur groupe amine est lié à l'atome de carbone adjacent au groupe acide carboxylique (le carbone α), ce qui leur confère la structure générique H2N–CHR–COOH, où R représente la chaîne latérale, qui identifie l'acide α-aminé. Les acides α-aminés jouent un rôle fondamental en biochimie comme constituants élémentaires des protéines : ils polymérisent en formant des liaisons peptidiques qui aboutissent à de longues chaînes macromoléculaires appelées peptides. Caractérisation Chrome Composés complexes Floculation Tannage au chrome Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The basic chromium salts give complex compounds with the amino-acids, by reatcions similar to those taking place in the tanning processes, between the reactive groups of the skin and the basic chromium salts. The present paper investigates the compounds formed between the aminoacids : glycine, serine, proline, lysine, asparagine, and aspartic acid, and the basic chromium salt from chrome alum. The electric charge, flocculation index, pH, and tanning ability were studied. Note de contenu : - EXPERIMENTAL : The electric charge - The flocculation index - Tanning behavior - DISCUSSION : Glycine - Serine - Proline - Lysine - Asparagine - Aspartic acid - Table 1 : Characterization of aminoacid complexed basic chromium salts En ligne : https://drive.google.com/file/d/1ehEZgUG2_AzHX5p21YaTS6JbR8Px0jVl/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41147 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Correlation of chrome and fat content with leather strength / E. H. Bitcover in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 121-125 Titre : Correlation of chrome and fat content with leather strength Type de document : texte imprimé Auteurs : E. H. Bitcover, Auteur ; A. L. Everett, Auteur Année de publication : 1978 Article en page(s) : p. 121-125 Note générale : Bibliogr. Langues : Américain (ame) 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 -- teneur en chrome Cuirs et peaux -- Propriétés physiques Cuirs et peaux -- Teneur en matières grasses Cuirs et peaux de bovins Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : In a previous study a variety of physical properties and sorting character-istics of combat boot leathers made from comparable bullhides and steerhides were closely compared. The cattle involved had similar genetic and management backgrounds as well as similar ages and slaughter weights. That study anticipated a possible trend towards raising young bulls for beef because of potential economic advantages. Results of the study indicated that leather from bullhide was significantly stronger by a number of standard tests than leather from steer-hide. Since the leathers had been processed in three different tannery lots, there was latex some question as to whether this had produced differences in chemical composition which could result in differences in physical properties. Note de contenu : - Table 1 : Average chemical composition of crust leathers (percent) - Table 2 : Average physical test results for crust leathers - Table 3 : Correlation of physical test results with chrome and fat content of 39 crust sides En ligne : https://drive.google.com/file/d/1t4ffoRfjm_dOE5pXSaxVgV8bDBGFBZB3/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41148 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Mini-symposium on modern beamhouse practices & problems / Eduardo V. Diharce in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 140-162 Titre : Mini-symposium on modern beamhouse practices & problems : held at Seventy-third annual meeting of the American Leather Chemists Association Type de document : texte imprimé Auteurs : Eduardo V. Diharce, Auteur ; Robert Sayers, Auteur ; Bruce D. Miller, Auteur ; Klaus H. Klein, Auteur ; Charles J. Cares, Auteur Année de publication : 1978 Article en page(s) : p. 140-162 Langues : Américain (ame) Catégories : Cuirs et peaux Travail de rivière (cuir) Index. décimale : 675 Technologie du cuir et de la fourrure Note de contenu : - INTRODUCTION - Eduardo V. Diharce - The versatility of the hide processor in conventional beamhouse operations - Robert Sayers - Low-lime unhairing - Bruce D. Miller - Sulfide recycling - Klaus H. Klein - A lime free unhairing system - Charles J. Cares En ligne : https://drive.google.com/file/d/1PNykaA1xbR2R3jggc6NA2jS9neN6Z1d2/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41149 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Water repellency / Thomas C. Thorstensen in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 196-203 Titre : Water repellency Type de document : texte imprimé Auteurs : Thomas C. Thorstensen, Auteur Année de publication : 1978 Article en page(s) : p. 196-203 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Acides gras Chrome Cuir -- Protection Dimère, Acide Hydrophobie Imperméabilisation Métaux Siloxanes Les siloxanes sont une classe de composés du silicium dont la formule empirique est R2SiO, où R est un groupe radical qui peut être organique. Des exemples représentatifs sont [SiO(CH3)2]n (diméthylsiloxane) et [SiO(C6H5)2]n (diphénylsiloxane), où n est typiquement supérieur à 4. Ces composés peuvent être des hybrides organiques et inorganiques. Les chaînes organiques confèrent au composé des propriétés hydrophobes alors que la chaîne principale -Si-O-Si-O- est purement inorganique. Le mot siloxane est dérivé de Silicium, Oxygène et alkane. Des siloxanes peuvent être trouvés dans des produits tels que des cosmétiques, des déodorants, des enduits hydrophobes pour pare-brise, des peintures et certains savons. Les siloxanes polymérisés (polysiloxanes) sont appelés silicones1,2. Le siloxane est massivement utilisé dans l'industrie cosmétique (rouges à lèvre, conditionneurs et shampooings, déodorants, etc.). Une application récente du Siloxane D5 (2001) a été trouvée dans le nettoyage à sec des textiles en remplacement du perchloroéthylène. Ce procédé est très répandu aux États-Unis et au Royaume-Uni. Il devient de plus en plus courant en Europe continentale dont la France, afin de promouvoir l'usage de procédés écologiques et respectueux de la santé humaine. Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The search for water repellency, comfort and durability of leather has led to the development of a wide variety of treatments for leather. These treatments differ in their theoretical basis, practical application, performance, and cost effectiveness. Note de contenu : - Fig. 1 : Symbols used to illustrate surface-active phenomena - Fig. 2 : a. A double layer produced by attraction of hydrophobie ends of fatty acids toward each other. b. Spewing of soap on surface under acid conditions - Fig. 3 : Water-repellent material based on the combination of fatty acid with a metal - Fig. 4 : a. Basic chromium stearato chloride. b. Chromium reacts with leather binding the fatty acid - Fig. 5 : Water-repellent systems based on fluoro fatty acids in combination with metals - Fig. 6 : A dimer acid derived from two unsaturated long-chain fatty acids possesses a cyclic nucleus with two hydrophobic chains and two carboxyl groups - Fig. 7 : Water repellency based on alkenyl succinic acids (ASA) - Fig. 8 : Schematic illustration of water repellency produced by ASA - Fig. 9 : General formula of siloxanes used in waterproofing leather En ligne : https://drive.google.com/file/d/1C1wUIg-hRzhAi9WYxgJPmCfzuu9VfBPZ/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41150 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Influence of animal factors and processing treatments on grain layer and total thickness of cattlehides / A. L. Everett in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 207-221 Titre : Influence of animal factors and processing treatments on grain layer and total thickness of cattlehides Type de document : texte imprimé Auteurs : A. L. Everett, Auteur ; Mary V. Hannigan, Auteur Année de publication : 1978 Article en page(s) : p. 207-221 Note générale : Bibliogr. Langues : Américain (ame) 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. Cuirs et peaux -- Epaisseur Cuirs et peaux de bovins Peau -- Histologie Wet-blue (tannage) Peau tannée au chrome (le chrome donne une couleur bleue) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Differences in physical structure between the grain (papillary) and corium (reticular) layers of cattlehides, and especially their final thickness ratio, have important effects on the physical properties of leather. Tanners need more data on the extent of variability of grain layer thickness in rawstock from different sources. The effects of cattle breed, sex, and age on 221 fresh hide biopsy samples from known sources and the effect of body location in seven identified hides were evaluated. While total thickness varied considerably with all factors, depth of grain layer increased very gradually with age and was essentially constant (1.5 to 2.0 mm) after one year. Breed and sex were also minor factors. Extensive data later found in the literature (summarized here) confirm and supplement our results and show that the grain is slightly deeper in colder climates and seasons. Information was also obtained on the changes in depth of grain layer induced by upper leather processing. Measurements from 168 wet-blue sides and 148 crust sides from 13 different commercial suppliers indicate that grain depth decreases from about 1.7 mm in rawstock to about 1.0 mm at the blue stage, and then to about 0.7 mm in dry leather. Certain retannages and finishing procedures may further modify this value. Correlations between grain and total thickness were relatively weak in rawstock, but stronger and more useful in unsplit blue stock. Note de contenu : - EXPERIMENTAL : Rawstock samples - Wet-blue samples - Crust leather samples - Histology - Measurements - RESULTS AND DISCUSSION : Rawstock measurements - Variation with body location - Wet-blue measurements - Crust measurements - Succession of changes - Correlation of grain and total thickness - Table 1 : Variation in fresh hide thickness with breed and age - Table 2 : Variation in fresh hide thickness with sex - Table 3 : Variation in salted hide thickness (mm) with body location - Table 4 : Variation in commercially processed side thickness with type of process - Table 5 : Regression of grain thickness on total thickness - Appendix table A : Survey of adult european cattle depth of grain - Appendix table B : Survey of asian, african, and south american cattle depth of grain En ligne : https://drive.google.com/file/d/1Ayqe_KSY6m-NyYX7ZEtZbERE42iFnXZp/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41151 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Studies on development and applications of a chemically modified glutaraldehyde / Peter M. Alford in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 250-267 Titre : Studies on development and applications of a chemically modified glutaraldehyde Type de document : texte imprimé Auteurs : Peter M. Alford, Auteur Année de publication : 1978 Article en page(s) : p. 250-267 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Chaulage Cuir -- Propriétés tinctoriales Cuir blanc Cuir nappa Cuirs et peaux -- Propriétés physiques Douceur (toucher) Glutaraldéhyde Matériaux -- Modifications chimiques Retannage Tannage Tannage au chrome Tannage végétal Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : With the development of a chemically modified glutaraldehyde, numerous new methods have been developed for its application in chrome tannage and improvement of the leather quality. Although it does not give quite the same fullness to the leather in retannage that glutaraldehyde does, the modified product is distinctly superior in its effect on the grain pattern, the softness and the dyeing properties of the resultant leather. Processes and results are discussed in some detail. Note de contenu : - RETANNAGE WITH MODIFIED GLUTARALDEHYDE : Chrome tannage - Vegetable tanning of lime split hides - White leather - Some aspects of tanning with modified glutaraldehyde - RETANNAGES WITH MODIFIED GLUTARALDEHYDE - Table 1 : distribution of ash and chromium oxide in the leather - Table 2 : Properties of lime split hides pretanned with modified glutaraldehyde and vegetable tanned by two methods - Table 3 : Effect of pH on chrome-tanned nappa leather pretanned with modified glutaraldehyde - Table 4 : Effect of adding salts in the chrome tanning of nappa leather - Table 5 : Influence of modified glutaraldehyde on fatliquor exhaustion En ligne : https://drive.google.com/file/d/1FA8ay_kgTRU0lOlIxPkF-5sK0TEM84jW/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41152 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Urethanes in leather finishing / Jon Bouchard in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 280-289 Titre : Urethanes in leather finishing Type de document : texte imprimé Auteurs : Jon Bouchard, Auteur Année de publication : 1978 Article en page(s) : p. 280-289 Langues : Américain (ame) Catégories : Cuirs et peaux -- Finition Isocyanates Polymères -- Propriétés physiques Polymérisation Polymérisation en émulsion Polyuréthanes Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Urethanes achieved commercial importance in the 1950's. Since that time, their growth has been phenomenal. Last year 5.3 billion pounds of isocyanates alone were used, and by 1983 the figure is expected to reach 8 billion pounds. The first use of urethanes in the leather industry was in the early 1960's when they replaced linseed oil as the patent leather topcoat. Today, urethanes are being tailor-made to solve a variety of leather finish problems. These new developments are expected to lead to increased volumes of urethanes in leather finishes. Note de contenu : - General chemistry - Primary isocyanate reactions : Amines - Water - Carboxylic acide - Substituted ureas - Urethane - Amides - Isocyanate polymerization : Dimerization - trimerization - Reaction rates and polymerization : Reactivity - Polymerization - Types of isocyanates ande alcohols : Isocyanates - Diols and polyols - Prepolymer types : Prepolymer - Fully reacted urethanes - Uretanes emulsions - Reactive urethanes - Table 1 : Physical properties of urethanes versus nitrocellulose lacquers En ligne : https://drive.google.com/file/d/1RCVW8UJCbFUTTXCNmuT1mx9VBq8Gr6gl/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41153 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

A comparative analysis of the comfort of leather and substitute materials, especially for footwear / Wilfried Diebschlag in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 307-332 Titre : A comparative analysis of the comfort of leather and substitute materials, especially for footwear Type de document : texte imprimé Auteurs : Wilfried Diebschlag, Auteur Année de publication : 1978 Article en page(s) : p. 307-332 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Chaussures -- Matériaux Confort Cuir Etudes comparatives Modèles mathématiques Pied Thermocinétique Transpiration Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : To develop the most satisfactory concept on which ta base the requirements for materials to he used for garments or footwear, the following data about man (which can vary among the different races) must be known : 1. Heat emission of different areas of the skin and heat distribution in the body, and 2. Water vapor and sweat emission from different areas of the skin. Both these factors must he considered under various conditions of stress and strain (physical or mental exercise, expressed in watts or joules per hour) ; under different climatic conditions (temperature, humidity, air movement) ; and with a variety of types of clothing. For 14 combinations of these factors, the basic data were established in tests over several years with subjects wearing different clothing under various conditions. At the same time, the physical properties of the materials worn were measured by test instruments, in particular such properties as their behavior towards water, water vapor, and heat, and their drying time. Note de contenu : - 1. INTRODUCTION : Wilson, the man who paved the way - The range of application of leather - 2. THE THERMOPHYSIOLOGICAL SURVEY OF MAN : THE BASIS FOR IMPROVED FOOTWEAR : Foot-sock-shoe as a microclimate functional system - Distribution of sweat glands and rate of sweat secretion - The influence of footwear on the microclimate in the shoe - Recommendations of the physiologist for shoe manufacturers - 3. THERMODYNAMIC PROGRAM FOR CALCULATION OF HEAT TRANSFER : Mechanisms of heat transfer from the body to the environment - Dry heat transfer - Evaporative heat transfer - Calculation for steady state - Examples of calculation fo r the functional system foot-shoe - Table 1 : Skin temperatures and heat and vapor flow under different conditions of activity, dress, and climate - Table 2 : Perspiration of man's body and foot compared to the water vapor characteristics of footwear materials - Table 3 : Constants for the calculation of variables Bi and Ti for various areas of the body - Table 4 : Physical characteristics of footwear - Table 5 : Physiological data of the foot when sitting or walking En ligne : https://drive.google.com/file/d/1MtcWd6Uqy4_IIWFlBxRmxcQWkyETU-UV/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41154 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Leather washfastness - the stabilizing effect of sulphate / D. E. Peters in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 333-342 Titre : Leather washfastness - the stabilizing effect of sulphate Type de document : texte imprimé Auteurs : D. E. Peters, Auteur Année de publication : 1978 Article en page(s) : p. 333-342 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Composés complexes Cuirs et peaux de moutons Peau lainée pH Résistance au lavage Sulfate de chrome Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The washfastness of leather in medical sheepskins (shearlings) decreases with use until it is insufficient to withstand a normal laundering cycle. The decrease in washfastness is normally attributed to loss of chrome from the leather, but it is found that the decrease is better correlated with loss of sulphate from the chrome complex. Improvements in washfastness can be achieved hy control of the pH during washing and by the addition of soluble sulphate to the wash liquor. Note de contenu : - Table 1 : Standard washfastness tests on medical shearlings at pH 8.5 - Table 2 : Washfastness tests on shearlings - effect of pH and sulphate concentration (wash test temperature 90°C) - Table 3 : Washfastness tests on shearlings - effect of sulphate concentration at optimum pH range (wash test temperature 90°C) En ligne : https://drive.google.com/file/d/1YO1Y_eBIkcjwm6d0dbXFfai1M8h0D8Yj/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41155 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

The environmental effects of chromium in tannery effluents / Stephen A. J. Shivas in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 370-377 Titre : The environmental effects of chromium in tannery effluents Type de document : texte imprimé Auteurs : Stephen A. J. Shivas, Auteur Année de publication : 1978 Article en page(s) : p. 370-377 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Boues résiduaires Chrome trivalent Chrome trivalent -- Oxydation Cuirs et peaux -- Industrie -- Aspect de l'environnement Eaux usées -- Teneur en chrome trivalent Environnement -- Etudes d'impact Membranes échangeuses d'ions Sols -- Chimie Sols -- Teneur en chrome Solubilité Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The chrome in tannery effluents is in the relatively nontoxic trivalent state, and not in sufficient concentrations to inhibit municipal sewage treatment. Municipal sludges applied to agricultural land could safely contain up to 500 ppm chrome. The final limitation of 112 ppm of chrome in soif is not realistic, since natural agricultural soils throughout the world contain more chrome than this. Adding chrome to the soil may even be beneficial, since many animal diets are chrome-deficient. Most leather is now tanned with chromium salts or vegetable and synthetic tannins and combinations of these (although considerable amounts of zirconium, alum, and glutaraldehyde are also in use). Since chromium is so widely used, it is important to consider the effects on the environment of the chemical state and concentrations in which it is discharged in tannery effluents and sludges. Note de contenu : - Chrome valencies - Properties of trivalent chrome - Solubility - Membrane permeability - Form of trivalent chrome in tannery effluent - Safe levels of trivalent chrome in biological oxidation - Effect of trivalent chrome in the soil - Chrome content in soils throughout the world - An alernative to tannery sludge disposal on agricultural land - Table 1 : Chromum content of digestedsludge from municipal sewage in sweden and Denmark En ligne : https://drive.google.com/file/d/1YWuHS1ywkVdcWCklq73zuP3ladianXaG/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41156 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Effect of finish thickness on the gloss of coated leathers / B. Lokanadam in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 378-386 Titre : Effect of finish thickness on the gloss of coated leathers Type de document : texte imprimé Auteurs : B. Lokanadam, Auteur ; N. Ramanathan, Auteur Année de publication : 1978 Article en page(s) : p. 378-386 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Brillance (optique) Cuirs et peaux -- Finition Polyacryliques Polymères en émulsion revêtements -- Epaisseur Revêtements organiques Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The gloss of the surface of finished leathers was found to increase with the thickness of the finish film. It also increased with the plating pressure up to a limit, beyond which the gloss decreased, probably due to the development of microcracks. The gloss was found to increase with the smoothness of the leather surface as seen in photomicrographs of the surface and of surface contour observed in cross-sections of the leathers. Phase-contrast optics used in conjunction with darkfield illumination revealed details flot seen by other optical microscopical methods. Note de contenu : - MATERIALS AND METHODS : Preparation of leathers for finishing - EXPERIMENTAL : Measurement of finish thickness - Reflected light microscope - Phase contrast microscop - RESULTS AND DISCUSSION - Table 1 : Characteristics of the acrylic resin emulsion - Table 2 : Amount of resin plus pigment coating material applied on corrected grain impregnated leathers En ligne : https://drive.google.com/file/d/1ceOF3QxTcWWoS1Q-ESD-8OKaHyhv3iQ-/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41157 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

The mechanical properties of collagen fibers / A. Rajaram in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 387-393 Titre : The mechanical properties of collagen fibers Type de document : texte imprimé Auteurs : A. Rajaram, Auteur ; R. Sanjeevi, Auteur ; N. Ramanathan, Auteur Année de publication : 1978 Article en page(s) : p. 387-393 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Cuirs et peaux Fibres de collagène -- Propriétés mécaniques Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The mechanical properties of collagen fibers, like stress-strain, hysteresis, work recovery, and stress relaxation, were studied as a function of length. It was found that there was a marked difference in behavior between fibers of short lengths as compared to those of longer oncs. This is explained on the basis of internat friction and probable length of fibrils. En ligne : https://drive.google.com/file/d/1z2e0JKAu243gCoRiTVrHD30mY5D1-Kmt/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41158 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Graft polymerization VI. Studies on proof of grafting and molecular weights of the isolated poly(methyl methacrylate) grafts / Helen A. Gruber in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 410-421 Titre : Graft polymerization VI. Studies on proof of grafting and molecular weights of the isolated poly(methyl methacrylate) grafts Type de document : texte imprimé Auteurs : Helen A. Gruber, Auteur ; Edward H. Harris, Auteur ; Stephen H. Feairheller, Auteur Année de publication : 1978 Article en page(s) : p. 410-421 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Acides aminés Les acides aminés (ou aminoacides) sont une classe de composés chimiques possédant deux groupes fonctionnels : à la fois un groupe carboxyle –COOH et un groupe amine –NH2. Parmi ceux-ci, les acides α-aminés se définissent par le fait que leur groupe amine est lié à l'atome de carbone adjacent au groupe acide carboxylique (le carbone α), ce qui leur confère la structure générique H2N–CHR–COOH, où R représente la chaîne latérale, qui identifie l'acide α-aminé. Les acides α-aminés jouent un rôle fondamental en biochimie comme constituants élémentaires des protéines : ils polymérisent en formant des liaisons peptidiques qui aboutissent à de longues chaînes macromoléculaires appelées peptides. Chimie analytique Copolymères greffés Cuirs et peaux de moutons Détérioration enzymatique Extraction (chimie) Homopolymères Polyméthacrylate de méthyle Le poly(méthacrylate de méthyle) (souvent abrégé en PMMA, de l'anglais Poly(methyl methacrylate)) est un polymère thermoplastique transparent obtenu par polyaddition dont le monomère est le méthacrylate de méthyle (MMA). Ce polymère est plus connu sous son premier nom commercial de Plexiglas (nom déposé), même si le leader global du PMMA est Altuglas International9 du groupe Arkema, sous le nom commercial Altuglas. Il est également vendu sous les noms commerciaux Lucite, Crystalite, Perspex ou Nudec. Tannage au chrome Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Chromium-tanned sheepskins were grafted with methyl methacrylate by a redox initiation system. The grafted product was exhaustively extracted to remove homopolymer, enzymatically degraded to remove the bulk of the protein, solvent fractionated to obtain a soluble fraction, and chromatographed on a controlled-pore glass column. Viscosity studies and amino acid analyses of the resulting material indicated that there were from one to three amino acids left in the peptide attached to the synthetic polymer chain. A single peak was obtained from the chromatographic column; however, the polydispersity of the polymer is demonstrated by the average molecular weights of 1,218,000 for the first half of the peak and 559,000 for the remainder. Molecular weights of the extracted homopolymers were somewhat less than those of the graft copolymers and were affected by the duration and temperature of the solvent extraction. Note de contenu : - EXPERIMENTAL : Chemicals and materials - Graft polymerization procedure - Total nitrogen determination - Homopolymer extraction - Isolation of the synthetic graft - Gel permeation chromatography - Viscosity determinations for molecular weight calculations - Amino acid analyses - IR spectra - RESULTS AND DISCUSSION : Characterization of the product of the polymerization - Characterization of the isolated graft copolymers - Results of molecular weight studies of graft copolymers - Results of molecular studies of extracted homopolymers - Fig. 1 : Properties of methyl methacrylate graft copolymer - Fig. 2 : Enzyme degradation procedure - Fig. 3 : Fractionation of enzyme degraded residue En ligne : https://drive.google.com/file/d/1biyf1Nlf_iELvtnw2UaOx7BdHPZKDSLk/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41159 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Effect of demodectic mange on the leather-making quality of indian goatskins / R. A. Venkatesan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 422-432 Titre : Effect of demodectic mange on the leather-making quality of indian goatskins Type de document : texte imprimé Auteurs : R. A. Venkatesan, Auteur ; M. Sugumar, Auteur ; S.-C. Nandy, Auteur Année de publication : 1978 Article en page(s) : p. 422-432 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Cuirs et peaux -- Analyse Cuirs et peaux -- Défauts Cuirs et peaux de chèvres Démodécie Parasitoses Peau -- Maladies chez les animaux Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Caprine demodecosis is causing great concern to the Indian leather trade as goatskins are considerably affected in quality by this defect. Demodectic mange mites were found to be lodged within subsurface nodules of the skin surrounded by dense fibrous tissue. In raw skin the nodules were bulged out on the flesh side only. The changes in appearance, variations in the number and distribution of nodules, and the effect on pelt and leather quality were studied af ter liming and after chrome or vegetable tanning for comparison with fresh skins. Histo¬pathological study revealed fibrous encapsulation around the nodules with no secondary bacterial infection. A few cases of the acute (squamous) form of demodecosis were noted in raw skin resembling sarcoptic mange infestation. Variations in number of nodules at different anatomical locations were significant. Amino acid composition of the skin in the affected area was compared with that in the unaffected area. Note de contenu : - MATERIALS AND METHODS : Vegetable tanning - Chrome tanning - Histopathology - Microscopical study of the etiological agent - Counts of demodectic nodules - Variation in anatomical distribution of nodules - Amino acid analysis - Procedure for analysis of nodule contents - RESULTS : Observations on demodecosis in untanned skins - Observations on crust leathers - Histopathological observations on demodectic nodules - Counts of demodectic nodules in skin sduring processing - Amino acid composition - Table 1 : Counts of demodectic nodules on 35 goatskins during lether processing - Table 2 : Anatomical distribution of demodectic nodules on limed pelts En ligne : https://drive.google.com/file/d/1dKtcFZCzGPOFg3b9vbRrmaGT4F8cDFhM/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41160 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

The vertical fiber hide defect : Transmission to progeny and relation to reproductive failures in crossbreding test / A. L. Everett in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 458-470 Titre : The vertical fiber hide defect : Transmission to progeny and relation to reproductive failures in crossbreding test Type de document : texte imprimé Auteurs : A. L. Everett, Auteur ; Mary V. Hannigan, Auteur Année de publication : 1978 Article en page(s) : p. 458-470 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Bovins -- Races Croisement de races Cuirs et peaux -- Analyse Cuirs et peaux -- Défaut de fibre verticale Cuirs et peaux -- Défauts Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Studies over the past 20 years have shown that the vertical fiber bide defect, which causes moderate to extreme weakness in leather, occurs much more frequently in Herefords than in the other two major cattle breeds examined so far. Evidence from several tests, including a recent hide biopsy study of twin Hereford and Holstein cows, supports the theory that this defect is a genetically controlled trait. We have now extended the biopsy study to include 76 progeny of these same cows, produced by reciprocal crossbreeding through three calvings, to test the incidence of the defect in known crossbreds. Although 13 of the Hereford dams and one of the Hereford sires carried the defect, only one of the calves was found to be defective. Samples were not available from three of the eight sires. Apparently the defect does not commonly occur from this type of crossbreeding. Analysis of the calving records from the crossbreeding test revealed preliminary evidence which, if confirmed by further testing on a larger scale, may have serious economic implications to the beef cattle industry. The Holstein cows produced a live calf crop of 86 percent of expected pregnancies and the normal Herefords produced 90 percent. However, the 13 defective Herefords produced only 70 percent and the five with extreme defect only 53 percent. Most of the Hereford failures were due to stillborn calves, especially from one pair of defective twins. Note de contenu : - EXPERIMENTAL : Test design - Biopsy procedure - Histology - Test hides and leather - RESULTS : Biopsy results for progeny - Analysis of calving records - Analysis of calving records - Incidence of calving failures - Pathological abnormalities - Table 1 : Evaluation of fiber structure in selected progeny of hereford cows with defect - Table 2 : Evaluation of fiber structure in selected progeny of hereford cow without defect - Table 3 : Evaluation of fiber structure in selected progeny of Holstein cows without defect - Table 4 : Calving records of hereford cows with defect - Table 5 : Calving records of hereford cows without defect - Table 6 : Calving records of Holstein cows without defect - Table 7 : Summary of reproductive performance data - Table 8 : Incidence of failures by breed, fiber, and feed groups En ligne : https://drive.google.com/file/d/1Tb6WU2S8hgp8eUAkNGSlZA3KqCc_1ueb/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41161 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Leather finishing by precision roll coating / William C. Prentiss in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 471-483 Titre : Leather finishing by precision roll coating Type de document : texte imprimé Auteurs : William C. Prentiss, Auteur ; Charles E. Cluthe, Auteur Année de publication : 1978 Article en page(s) : p. 471-483 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Cuirs et peaux -- Finition Enduction au rouleau Formulation (Génie chimique) Héliogravure Nitrocellulose Solutions (chimie) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Coatings for film, sheet, or strip metal and building products have been applied by roll or gravure for some time. In recent vears, the application of these techniques to leather finishing has been studied to improve finish utilization and reduce solvent emission. These benefits are substantiated by the results of this work. Finishing can be achieved with about one-half the solids add-on of spray application and without the over-spray waste. Further, the solids of applied coatings can be more than twice those of spray finishes, thus reducing solvent emission further. However, precision roll coating appears to be less than ideal, since at best there is a compromise between face, fill and uniformity as influenced by the tracking pattern. The same lacquers as applied by roll coatings, but reduced with thinner and sprayed generally produce excellent face, fill, and uniformity of leather appearance. In general, the technology and mechanics of precision roll coating require, for trouble-free production, someone who is skilled in finish formulation and has a good understanding of the equipment. Note de contenu : - EXPERIMENTAL : Precision gravure roll coater - Formulations and finishing procedures - RESULTS AND DISCUSSION : Performance of nitrocellulose solutions - Machine parameters - Table 1 : Effect of gap dimension between feed and applicator rolls on finish add-on and tracking - Table 2 : Influence of roll speed on finish add-on and tracking - Table 3 : Influence of gravure foll engraving on relative add-on En ligne : https://drive.google.com/file/d/10EHjtmqh1NXeWK3HOhAYz7bo4LW_4W8p/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41162 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Controlling fungal growth on leather : correlation of TCMTB uptake and duration of mold resistance / John M. van Deren in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 498-507 Titre : Controlling fungal growth on leather : correlation of TCMTB uptake and duration of mold resistance Type de document : texte imprimé Auteurs : John M. van Deren, Auteur ; Edward F. Weiss, Auteur Année de publication : 1978 Article en page(s) : p. 498-507 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Absorption Champignons microscopiques Croissance microbienne Cuirs et peaux -- Conservation Fongicides Résistance à la moisissure Thiocyano-méthylthiobenzotiazole Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The compound, 2- (thiocyanomethylthio) benzothiazole (TCMTB) has proven effective for controlling fungal growth on leather. Good protection of the hides requires addition of the fungicide in a manner that assures its maximum transfer to the hide from the liquor to which it is added. Experiments with TCMTB labeled with radioactive carbon-14 showed that uptake of the fungicide by the hides was greatest when the TCMTB was added as soon as practical in the tanning process. When TCMTB was added to the chrome liquor at the beginning of tanning, over 90 percent of it was taken up by the hides, while adding the fungicide three hours af ter the start of tanning reduced the uptake to 77 percent. Exposure of treated hides in a tropical chamber showed that the duration of mold resistance was directly related to TCMTB uptake. Hides containing 100 ppm of TCMTB remained free of any visible fungal growth for over 25 days under these severe conditions. Note de contenu : - Fungal growth on leather - Controlling fungal growth - Correlation of TCMTB uptake and mold resistance - Table 1 : Effect of contact time on TCMTB uptake of hides - Table 2 : TCMTB uptake by leather vs. time after addition - Table 3 : Extraction of TCMTB-14C from hide samples En ligne : https://drive.google.com/file/d/1giu_jzhyyq-FqdfQqINITk6Vn9iQ_fka/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41163 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Vegetable tan wastage in typical sole leather processes / Stanley G. Shuttleworth in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 508-514 Titre : Vegetable tan wastage in typical sole leather processes Type de document : texte imprimé Auteurs : Stanley G. Shuttleworth, Auteur ; Neville P. Slabbert, Auteur ; David A. Boast, Auteur ; Thomas Eberle, Auteur Année de publication : 1978 Article en page(s) : p. 508-514 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Cuirs et peaux Gaspillage -- Lutte contre Prétannage Semelles Tanins végétaux Tannage végétal Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : In view of the high oxygen demand and resistance to biodegradation of vegetable tannins, tightening effluent standards require processes which minimize vegetable tan wastage in sole leather production. A study is made of typical modem processes, including bleach and wash liquors, in order to ascertain optimum methods of minimizing vegetable tannins in the effluent. It is concluded that the Liritan process can give 95 percent tan utilization if the color vat operates alternately as a tempering vat to eliminate bleach and wash liquors. Next in order of economy is a weak liquor suspender system followed by a powder drum tannage. Unacceptably high tan wastage appears to occur in an all-drum tannage with syntan pretannage or an all-pit counter current process. Note de contenu : - Water gain in vegetable tanning - Comparison of various processes : Countercurrent all-pit processes - The all-drum process - Weak suspender plus drum processes - The liritan process - Finishing processes - General notes on the economics of pretanning systems - General conclusions En ligne : https://drive.google.com/file/d/1OvEhTMdCvY_0HYNsY3bRzgkTUxlxE47n/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41164 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Graft polymerization VIII. Effect of changes in the initiating system on the molecular weight of the graft copolymer in polyretanned leather / Helen A. Gruber in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 530-536 Titre : Graft polymerization VIII. Effect of changes in the initiating system on the molecular weight of the graft copolymer in polyretanned leather Type de document : texte imprimé Auteurs : Helen A. Gruber, Auteur ; Maryann M. Taylor, Auteur ; Edward H. Harris, Auteur ; Stephen H. Feairheller, Auteur Année de publication : 1978 Article en page(s) : p. 530-536 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Copolymères greffés Cuirs et peaux de moutons Oxydoréduction Poids moléculaires Polymérisation Polyméthacrylate de méthyle Le poly(méthacrylate de méthyle) (souvent abrégé en PMMA, de l'anglais Poly(methyl methacrylate)) est un polymère thermoplastique transparent obtenu par polyaddition dont le monomère est le méthacrylate de méthyle (MMA). Ce polymère est plus connu sous son premier nom commercial de Plexiglas (nom déposé), même si le leader global du PMMA est Altuglas International9 du groupe Arkema, sous le nom commercial Altuglas. Il est également vendu sous les noms commerciaux Lucite, Crystalite, Perspex ou Nudec. Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Research was conducted to determine the effects of changes in the initiation system on the grafting of methyl methacrylate onto chromium-tanned sheepskins. The molar ratio of reductant ( NaHS03) to oxidant (K2S208) was varied over the range of 0.05:1 to 2:1 to study the effect on the molecular weight of the isolated grafted synthetic polymer. This produced a striking effect in tertres of bound polymer and its molecular weight. A definite correlation, relating to the grafting efficiency of the leather, was found between the amount of reductant used and the percent polymer bound and extractable homopolymer. The grafted leathers were exhaustively extracted with ethyl acetate to remove homopolymer, then acid hydrolyzed to remove essentially all of the collagen substrate. Viscosity studies on the isolated grafted synthetic polymers indicated that there is an inverse relationship between the average molecular weight of the graft and the amount of reductant used for grafting at a fixed level of oxidant. The molar ratio giving the highest grafting efficiency was 0.2:1.0, reductant to oxidant. Note de contenu : - Table 1 : Effects of molar ratio of redox system on graft copolymers En ligne : https://drive.google.com/file/d/1i79nku2hS3nGn0YAPaQYGSmW3abVpGb2/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41165 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt

Hide puller damage and the vertical fiber defect / A. L. Everett in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXIII (Année 1978)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXIII (Année 1978) . - p. 537-542 Titre : Hide puller damage and the vertical fiber defect Type de document : texte imprimé Auteurs : A. L. Everett, Auteur ; David G. Bailey, Auteur ; Mary V. Hannigan, Auteur Année de publication : 1978 Article en page(s) : p. 537-542 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Analyse de dommages (matériaux) Peaux brutes -- Détérioration Peaux brutes -- Extraction -- Appareils et matériels Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : One of the many ways of increasing efeciency in the meat packing industry has been the substitution of hide pulling machines for the old method of hand flaying with knives. Several distinctly different types of machines and procedures have been developed for bide removal. It was estimated in 1972 that 75 percent of United States hides were removed with pullers. This has resulted in a general improvement in hide quality due to a significant decrease in hutcher cuts. However, this procedure, especially with the newer "clown puller," can exert so much force that it could cause considerable grain-crack damage at various hide locations. This damage ("grain break") was described and illustrated in a pamphlet issued by the Tanners' Hide Bureau in 1972. Tancous also pointed out that, while hide pulling machines greatly reduced the damage from flay cuts, they may introduce new damage from grain cracks. Proper handling and adjustment of machines have been shown to minimize this problem. Some packers and hide dealers feel that hides identified as Hereford hy their hair color may be the most troublesome in this respect. If so, then perhaps the weakness caused by the vertical liber defect, which occurs most frequently in these Hereford-type hides, may be responsible. A packer with this thought in mind offered to cooperate with us to obtain further information. Note de contenu : - Table 1 : Defective sides : puller damage and leather strength - Table 2 : Normal sides : puller damage and leather strength - Table 3 : Leather from selected hides : puller damage and defect En ligne : https://drive.google.com/file/d/1uU6sW3_aUHT6N7rrsuowqYWmNsu30awB/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=41166 [article]

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
011628	-	Périodique	Bibliothèque principale	Documentaires	Exclu du prêt