Studies on the influence of power ultrasound on dye penetration in leather dyeing using photomicrographic analysis

Abstract

SummaryThe use of power ultrasound in enhancing diffusion rate in various chemical as well as physical processes is gaining in importance. The influence of power ultrasound in the leather dyeing process on enhancing the penetration of dye through the leather matrix was studied. The penetration of dye through a leather cross-section for a given time in the presence and absence of an ultrasonic field (33 kHz, 150 W) was studied by photomicrographic analysis using a stereomicroscope. Different types of black dyes, such as Acid black 1, Metal complex black 194 and Direct black 155, were used for dyeing leather in the present study. Photomicrographic analysis of a cross-section of dyed leather indicated better penetration of dyes through the leather matrix with the use of ultrasound than without it. Therefore, the results indicate that ultrasound helps to improve the diffusion of dye and to reduce diffusional resistance in the leather dyeing process.

Power ultrasound in fatliquor preparation based on vegetable oil for leather application

“…In this paper, fatliquor emulsion preparation based on castor oil using ultrasound has been discussed. The use of ultrasound for enhancing the fatliquoring process has also been studied [12]. Due to the growing demand for the good quality leather auxiliary chemicals, newer processing techniques are gaining importance.…”

Amphiphilic acrylate copolymer fatliquor for ecological leather: Influence of molecular weight on performances

“…Photomicrographs were taken under 403 magnification, suitable for examining the whole cross-section under the microscope. 18 Total organic carbon (TOC) is an important indicator characterizing the residual chemicals in effluents. The absorption ratio of leather chemicals can be approximately equal to the TOC removal ratio from post-neutralization to post-fatliquoring.…”

Sustainable Ultrasound-Assisted Ultralow Liquor Ratio Dyeing of Wool Textiles with an Acid Dye

“…In the case of leather dyeing, it was observed that ultrasound influenced the penetration of dye through the leather matrix. 16 Sanislav et al observed lower agglomeration of dye in the ultrasound-assisted dyeing of wool with reactive dyes compared to the classic dyeing of wool with the same dyes. 17 However, none of these studies deal with the problems needed to overcome dye agglomeration at ultralow liquor ratios.…”

“…Leather is composed of polypeptides containing amino acids similar to wool fiber (but without any sulfur linkage) and is dyed with the same class of dyes used in wool fiber dyeing. In the case of leather dyeing, it was observed that ultrasound influenced the penetration of dye through the leather matrix . Sanislav et al observed lower agglomeration of dye in the ultrasound-assisted dyeing of wool with reactive dyes compared to the classic dyeing of wool with the same dyes .…”