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Correlation of visual and instrumental color measurements to establish color tolerance using regression analysis / Malathy Jawahar in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CX, N° 12 (12/2015)
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Titre : Correlation of visual and instrumental color measurements to establish color tolerance using regression analysis Type de document : texte imprimé Auteurs : Malathy Jawahar, Auteur ; Swarna Vinodh Kanth, Auteur ; R. Venba, Auteur ; Chandra Babu Narasimhan Kannan, Auteur Année de publication : 2015 Article en page(s) : p. 409-419 Note générale : Bibliogr. Langues : Américain (ame) Catégories : Colorimétrie
Couleur -- Analyse
Cuirs et peaux -- Teinture
Evaluation visuelle
Statistique
vision des couleursIndex. décimale : 675 Technologie du cuir et de la fourrure Résumé : Color is one of the important parameter considered in the determination of quality for fashion materials like leather. The color variation in each piece of leather sample in a batch should be within the acceptable range. Visual assessment is currently used in leather industry for quality control and color sorting. The current method used is subjective and often leads to disagreement between buyer and seller. Color measurement using reflectance spectrophotometer evaluates color consistently and is an objective assessment system. However, there is always an apprehension that the instrumental color assortment may not agree with the human perception of color difference. Hence, in the present investigation, an attempt was made to screen four color difference formulae, viz., CIELAB76, CMC (2:1), CIE94 and CIE2000 for their suitability in obtaining pass/fail decisions, which would be in conformity with that of the average human observer. Regression analysis was performed to find a correlation between visual and instrumental color assessments and the results indicate that CM (2:1) formula may be the most suited for the purpose. A detailed analysis of visual and instrumental color values revealed visual non uniformity towards sensitivity to hue, chroma and lightness. This difference in sensitivity was also taken into consideration in instrumental color sorting and pass/fail tolerance was established that led to closer conformity between visual and instrumental methods. Note de contenu : - MATERIALS AND METHODS : Materials - Methods : Visual assessment of color tolerance - Instrumental color analysis - Curve fitting and statistical analysis
- RESULTS AND DISCUSSION : Statistical color analysis - Analysis on instrument and visual color perception - Color sorting with two dimensional groupingEn ligne : https://drive.google.com/file/d/1XyT_llW7hzfrkDAGx7oDogTiBBBGc40h/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=25051
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Code-barres Cote Support Localisation Section Disponibilité 17652 - Périodique Bibliothèque principale Documentaires Disponible Effect of different retanning systems on surface properties of leather / Swarna Vinodh Kanth in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CII, N° 4 (04/2007)
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Titre : Effect of different retanning systems on surface properties of leather Type de document : texte imprimé Auteurs : Swarna Vinodh Kanth, Auteur ; A. Ipe, Auteur ; Balaraman Madhan, Auteur ; R. Venba, Auteur ; Aruna Dhathathreyan, Auteur Année de publication : 2007 Article en page(s) : p. 135-142 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : The present work attempts to analyze the surface properties of crust leathers processed using different syntans of the type phenol-naphthalene formaldehyde condensate, phenol formaldehyde, melamine formaldehyde, gluteraldehyde, styrene maleic anhydride, acrylic polymer, sulphone and heterocyclic N-methylol. Contact angles of liquid drops on the leather surfaces have been used to evaluate surface energy, acidity, basicity, polarity, work of adhesion and surface roughness. The surface energy component showed that the control crust leather without retanning is practically monopolar basic with S- = 13.02 mN/m. Acrylic polymer retanned crust leather exhibited high basic character (carreS- = 33.15 mN/m), while phenol formaldehyde retanned crust leather had the least values (S- = 1.03 mN/m). The surface behavior towards rub fastness and adhesion of finish has been significantly altered by the retanning systems in leathers and showed a good correlation with the surface properties like surface charge, polarity, roughness and work of adhesion. En ligne : https://drive.google.com/file/d/1G00lD6GLJORh9mU-qS1cQEpc3mcY2SYZ/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3362
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Code-barres Cote Support Localisation Section Disponibilité 007154 - Périodique Bibliothèque principale Documentaires Disponible Elimination of hexavalent chromium in leather using reducing agents / Chandra Babu Narasimhan Kannan in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. C, N° 9 (09/2005)
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Titre : Elimination of hexavalent chromium in leather using reducing agents Type de document : texte imprimé Auteurs : Chandra Babu Narasimhan Kannan, Auteur ; R. Venba, Auteur ; G. Jothi, Auteur ; B. Ramanaiah, Auteur Année de publication : 2005 Article en page(s) : p. 354-359 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : The presence of hexavalent chromium, Cr(VI) in leather and leather products has become a source of concern to the leather industry. Consequently research efforts are being made to identify the source of Cr(VI) and eliminate it in finished leathers. This paper deals with the study on the use of reducing agents based on sulfur and phosphonium compounds for elimination of hexavalent chromium in the leathers. Sodium bisulfite and tetrakis-hydroxymethylphosphonium sulfate were found to eliminate hexavalent chromium well below the detectable limit. The performance of these two compounds has also been studied by the external addition of dichromate in processing. En ligne : https://drive.google.com/file/d/1YfoHwIlwzd-Vdq-P7cHMIOIG_2qZ5fQS/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4057
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Code-barres Cote Support Localisation Section Disponibilité 003081 - Périodique Bibliothèque principale Documentaires Disponible Instrumental assessment of levelness of dyed materials / Malathy Jawahar in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. XCIX, N° 6 (06/2004)
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Titre : Instrumental assessment of levelness of dyed materials Type de document : texte imprimé Auteurs : Malathy Jawahar, Auteur ; G. Jyothi, Auteur ; R. Venba, Auteur ; M. Jinandra Doss, Auteur ; Chandra Babu Narasimhan Kannan, Auteur Année de publication : 2004 Article en page(s) : p. 233-241 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675 Technologie du cuir et de la fourrure Résumé : Levelness in dyeing is assessed traditionally in leather industry by subjective visual method or grading using a grey scale. In the present investigation, an attempt has been made to develop a reliable objective method for the assessment of levelness based on instrumental techniques. Three methods based on Mean Delta ECIE (color difference based on method of Commission International de I'Eclairage), Mean Delta ECMC (color difference based on method of Color Measurement Committee of the Society of Dyers and Colorists, U.K) and Relative Unlevelness Index (RUI) were screened for use on leather substrate and compared with the visual assessment method. The study was carried out for 13 shades on goat upper leathers. Results show that the method based on Mean Delta ECMC is the most suitable for all the shades and has a good correlation with the visual assessment rating. En ligne : https://drive.google.com/file/d/1H-JxLuux1DgvA8DJeZOqVgnd2G7GBhJd/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=4196
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Code-barres Cote Support Localisation Section Disponibilité 001603 - Périodique Bibliothèque principale Documentaires Disponible Novel approach towards high exhaust chromium tanning - Part I : role of enzymes in the tanning process / R. Venba in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CIII, N° 12 (12/2008)
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Titre : Novel approach towards high exhaust chromium tanning - Part I : role of enzymes in the tanning process Type de document : texte imprimé Auteurs : R. Venba, Auteur ; Chandra Babu Narasimhan Kannan, Auteur ; Swarna Vinodh Kanth, Auteur Année de publication : 2008 Article en page(s) : p. 401-411 Note générale : Bibliogr. Langues : Américain (ame) Index. décimale : 675.2 Préparation du cuir naturel. Tannage Résumé : Stringent environmental regulations on the discharge of pollutants from various industries have prompted researchers to seek the development of eco-benign technologies and process innovations aimed at low-waste and high exhaust chrome tanning systems. However, an effective biotechnological solution for reducing chromium pollution that is cost effective, commercially adaptable high exhaustion chrome tanning process has not been explored. In the present investigation, an attempt has been made to bring about enzyme assisted chrome tanning process using acid protease. The effect of varying conditions of enzyme treatment on the exhaustion of the chrome tanning agent have been studied and the conditions optimized. Three different control chrome tanning systems have been chosen with and without float in the tanning process. In order to have a comparative study, chrome tanning at an offer of 6% and 8% basic chromium sulphate (BCS) in experimental processes has also been performed. It has been observed that the penetration and distribution of chromium is much better for enzyme assisted chrome tanning process at pH 4.5 compared to other systems. There is no surface deposition of chromium in the experimental leathers, although chrome tanning has been carried out at higher pH of 4.5. This has been substantiated through scanning electron microscopic analysis. Chromium exhaustion greater than 95% has been achieved in optimized enzyme assisted chrome tanning systems. The amount of chromium present in these leathers has been relatively higher compared to conventional chrome tanned leathers. The performance characteristics assessed by physical and tactile evaluation of the enzyme assisted leathers has been on par with conventional leathers. En ligne : https://drive.google.com/file/d/16ylAk4UqoEkocabwiRiWInyAsONnQAnM/view?usp=drive [...] Format de la ressource électronique : Permalink : https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=3253
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Code-barres Cote Support Localisation Section Disponibilité 010910 - Périodique Bibliothèque principale Documentaires Disponible Studies on solubilized sulfur dyes for coloring leather / R. Venba in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CX, N° 6 (06/2015)
PermalinkStudies on the influence of proteolytic enzymes in leather dyeing / Swarna Vinodh Kanth in JOURNAL OF THE AMERICAN LEATHER CHEMISTS ASSOCIATION (JALCA), Vol. CI, N° 12 (12/2006)
PermalinkStudy on compatibility of acid dyes : assessment using a computer colour matching system / Chandra Babu Narasimhan Kannan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 81, N° 3 (05-06/1997)
PermalinkThe renaissance of Fe(III) as self-tanning agent / R. Karthikeyan in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC), Vol. 95, N° 4 (07-08/2011)
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