Assessment of vegetable tannin extracts by colorimetry / Timothy D. Stilwell in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCVI, N° 6 (06/2001)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. XCVI, N° 6 (06/2001) . - p. 192-204 Titre : Assessment of vegetable tannin extracts by colorimetry Type de document : texte imprimé Auteurs : Timothy D. Stilwell, Auteur ; Bruce W. Buehrig, Auteur ; Robert J. Harvey, Auteur ; L. Shepley Hermann, Auteur ; Jean J. Tancous, Auteur Année de publication : 2001 Article en page(s) : p. 192-204 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Spray-dried, untreated wattle and treated quebracho extracts were tested for color by four laboratories equipped with Lovibond Tintometers. A comparison of color readings was conducted at the U.S.H.S.L.A. Laboratory where more reasonably priced meters, a Jenway Colorimeter and a Milton-Roy Spectrophotometer, were used. Time for testing was shortened considerably because preliminary tannin analyses were not done and the meters were simpler to operate. Samples of extracts were weighed, dissolved in distilled water, heated to 82oC, cooled and read immediately. A ratio, constructed by dividing yellow readings by red readings, was found to be a valuable method for understanding factors that influence color such as pH and addition of reagents. En ligne : https://drive.google.com/file/d/149LW5NP9yrPYRBQMilRHVQ4FIsZpsm8H/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4371 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001564	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Evaluation of modifications to the alca standard method for tannin analysis in tannery liquors / Robert J. Harvey in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCVIII, N° 4 (04/2003)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. XCVIII, N° 4 (04/2003) . - p. 147-152 Titre : Evaluation of modifications to the alca standard method for tannin analysis in tannery liquors Type de document : texte imprimé Auteurs : Robert J. Harvey, Auteur ; Bruce W. Buehrig, Auteur ; Timothy D. Stilwell, Auteur ; L. Shepley Hermann, Auteur Année de publication : 2003 Article en page(s) : p. 147-152 Note générale : Biliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The American Leather Chemists Association (ALCA) Standard Method for tannin analysis was developed to provide tanners with a way to monitor the relative strength of tan liquors in their process. Although it took full advantage of existing technology in the early 1900's, that method is very restrictive, laborious and time consuming. Advances in filtering technology allow modern researchers to process materials much more efficiently than in the past. Several filtration methodologies were incorporated into existing ALCA methods, and modifications were evaluated for time efficiency, effectiveness, and comparability to the Standard Methods. Direct determination of solids on undiluted tan liquor was evaluated against the Standard Method procedures. En ligne : https://drive.google.com/file/d/1cvdwHw345S9jYb8pXl0tTH9-JDzA_-Vb/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4117 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001586	-	Périodique	Bibliothèque principale	Documentaires	Disponible

Pratical evaluation of ethylenediaminetetra-acetic acid for controlling iron stains on vegetable tanned leather / Timothy D. Stilwell in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCVI, N° 12 (12/2001)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. XCVI, N° 12 (12/2001) . - p. 481-490 Titre : Pratical evaluation of ethylenediaminetetra-acetic acid for controlling iron stains on vegetable tanned leather Type de document : texte imprimé Auteurs : Timothy D. Stilwell, Auteur ; Mark W. Armstrong, Auteur ; Jean J. Tancous, Auteur ; L. Shepley Hermann, Auteur ; W. Buehrig, Auteur Année de publication : 2001 Article en page(s) : p. 481-490 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Tanners of vegetable tanned leather have observed that when iron contacts moist or wet leather it causes gray to black stains. For years, the chelating agent, ethylenediaminetetraacetic acid (EDTA), has been added to dry tannin extracts and to tanning liquors to prevent iron stains. This study was conducted to find out how much iron is present in tannins and in tan liquors and to find out how much iron, in the absence of EDTA, would be needed to cause iron stains. Analytical analyses and color determinations, using sheepskin skivers and colorimetry, showed that EDTA, an expensive chemical, did not need to be added during tanning and retanning of vegetable tanned leather. En ligne : https://drive.google.com/file/d/1Zchpl1gke9tqq6d_aIsFmVsiVU6Zxp7U/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4347 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
001569	-	Périodique	Bibliothèque principale	Documentaires	Disponible

A study of various types of soaks on the rehydratation of brine cured hides used for vegetable tanned leather / Jean J. Tancous in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. LXXXIX, N° 8 (08/1994)  

[article]  inJOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA) > Vol. LXXXIX, N° 8 (08/1994) . - p. 241-259 Titre : A study of various types of soaks on the rehydratation of brine cured hides used for vegetable tanned leather Type de document : texte imprimé Auteurs : Jean J. Tancous, Auteur ; Waldo E. Kallenberger, Auteur ; Bruce W. Buehrig, Auteur ; L. Shepley Hermann, Auteur Année de publication : 1994 Article en page(s) : p. 241-259 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Six different soaking methods (three enzyme and three older, conventional methods) were compared for their effectiveness in rehydrating the center portion of brine cured hides used for vegetable tanned leather. An enzyme method, which employed the use of a protease plus surfactant was the best of the six methods tried. Added advantages of the protease plus surfactant method were found, such as a significant reduction in the number of center hard spots in the leather, a cleaning of the grain and underlying hair pocket region that has eliminated the bating procedure, a 45 percent reduction in soaking time over conventional methods, and a 40 percent reduction in the amount of sulfides used for unhairing. En ligne : https://drive.google.com/file/d/1Iebj7wthRAx23zBWa4-_EGgIRAoQB5k3/view?usp=drive [...] Format de la ressource électronique : Pdf Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=8059 [article]

Réservation

Réserver ce document

Exemplaires (1)

Code-barres	Cote	Support	Localisation	Section	Disponibilité
006921	-	Périodique	Bibliothèque principale	Documentaires	Disponible

---

1 (1 - 4 / 4)