Titre : |
Tannage/retannage methods for reduction of between-skin colour variation |
Type de document : |
texte imprimé |
Auteurs : |
John R. Barlow, Auteur |
Année de publication : |
1977 |
Article en page(s) : |
p. 121-128 |
Note générale : |
Bibliogr. |
Langues : |
Anglais (eng) |
Catégories : |
Colorimétrie Cuirs et peaux Retannage Tannage au chrome
|
Index. décimale : |
675.2 Préparation du cuir naturel. Tannage |
Résumé : |
Full chrome leathers were prepared, using the same total amount of tanning agent for all samples but varying the proportions offered in the initial tannage and in the retannage (after storage). Quantitative measurements showed that those batches which received a low level of initial tannage and a substantial retannage had less colour variation than those given a fuller initial tannage and smaller retannage. The improvement was seen even after dyeing to a medium brown. Only after dark, surface dyeing were colour differences of the batches brought to a similar level.
Chrome retan leathers were also made, with the chrome tanning being carried out in either one step or as a low-level initial process with a retannage to the required Cr2O3 content immediately before subsequent processing. Batches of skins from the latter method were move level than those from the one-step chrome tanning process, with the improvement still being considerable after vegetable retanning and dyeing to a medium brown. Bleaching, by the use of a proprietary Syntan, only marginally reduced the variation of colour within any pack. |
Note de contenu : |
- Instrumental measurement of colour variation and its relevance to visual assessments
- Colour measurement
- Fig. 1 : Mean ΔE for individual batches at different stages of processing full-chrome leathers
- Fig. 2 : Mean ΔE for paired batches at different stages of processing full-chrome leathers
- Fig. 3 : Percentage of skins differing from mean by more than 1.0 ANLAB unit (full-chrome leathers)
- Fig. 4 : Mean ΔE at different stages of processing chrome retan leathers
- Fig. 5 : Percentage of skins differing from mean by more than 1.0 units. Chrome retan leathers
- Table 1 : Processing for full-chrome leathers
- Table 2 : Processing of chrome retan leathers
- Table 3 : Processing of chrome retan leathers - Details
- Table A : Results of subjective testing - Numbers of assessors seeing difference
- Table B : Statistical significance of colour assessments
- Table C : Results of colour measurements of commercial leathers
- Appendix 1 : Instrumental measurement of colour variation
- Appendix 2 : Relationship between visual assessment and instrumental ΔE values
- Appendix 3 and 4 : Results of colour measurements of commercial leathers |
En ligne : |
https://drive.google.com/file/d/1ZVrm05-hhU61Rgx4fHY2rH5i4yHL5juJ/view?usp=drive [...] |
Format de la ressource électronique : |
Pdf |
Permalink : |
https://e-campus.itech.fr/pmb/opac_css/index.php?lvl=notice_display&id=34122 |
in JOURNAL OF THE SOCIETY OF LEATHER TECHNOLOGISTS & CHEMISTS (JSLTC) > Vol. 61, N° 6 (11-12/1977) . - p. 121-128