Investigations on the general properties of biomass-based aldehyde tanned sheep fur for its selective post-tanning processing

Dialdehyde sodium alginate(DSA)is an alternative chrome-free tanning material for fur production.To obtain satisfactory resultant fur and provide suggestions for the usage of DSA in fur making,the general properties of DSA tanned sheep fur were systematically investigated.The tanning mechanism of DSA was analyzed and it was verified that DSA was mainly combined with collagen fiber by forming Schiff base covalent bonds while supplemented by a small number of hydrogen bonds and ionic bonds.Due to the acid sensitivity of Schiff base structure,DSA tanned fur had poor resistance to acid rinsing but had excellent resistance to washing and good fatliquoring performance.Also,it had good resistances to yellowing and reductant.After being retanned by chrome tanning agent,the fur was capable of enduring a high-temperature dyeing process(68°C for 8 h).Overall,DSA tanned sheep fur had favorable properties under appropriate post-tanning processing conditions to manufacture light-colored or dark-colored fur products with desirable physical properties.

Application of amphoteric polymers in the process of leather post-tanning

With the characteristics of controllable charge and environmental friendliness,amphoteric polymers can be used in post-tanning process to solve the problems that arise during leather making and are caused by the low absorption rate of single-charge chemicals,incompatibility with new tanning methods,and complex operation process.In this review,the structure,performance,and preparation of amphoteric polymers are reported.Then,the charge change of collagen during different tanning and pH treatments is introduced.Finally,the application and development of amphoteric polymers during the post-tanning process of leather making are discussed.This review has certain guiding significance to the preparation and application of amphoteric polymers for tanning system.

An insight into artisanal leather making in Ghana

The production of leather from animal skins and hides through tanning processes began in the pre-historic ages.Despite the origination of new leather making techniques such as chrome tanning which is being employed extensively today,the traditional method of leather production primarily through vegetable tanning is still being practised mostly in artisanal tanneries in developing nations including Ghana.Artisanal leather making,thus,contributes beneficially to rural livelihood.Nevertheless,the growth of this sector has been stifled by the lack of innovative technologies to enhance productivity.This challenge could be partly linked to the knowledge gap on the scientific principles governing artisanal leather production processes.This study,therefore,elaborates on various process steps and materials employed in traditional leather making in Ghana and the scientific principles underlying each of the processes.It also makes a comparison between traditional and modern leather manufacturing processes and identifies knowledge and technological gaps which would inspire in-depth scientific research into artisanal leather making.