Japanese angelshark is eaten and the rough skin is made into a type of leather called shagreen for use in wood finishing. Angel sharks in general are highly threatened by commercial trawl fisheries due to their susceptibility to capture and low rate of reproduction, and angel shark species elsewhere are known to have declined markedly under fishing pressure. Trawling activity in the Yellow Sea and other parts of the northwestern Pacific is intense and, coupled with pollution, has had a serious impact on the local ecosystem. The Japanese angelshark population is suspected to have declined by up to 50% or more under
Liming (leather processing) weight also needs to take into consideration that proteins (especially the hair) have been removed, and the fleshing operation is often performed after liming. The action of liming, in particular the swelling of the skin, results in the splitting of the fibre bundle sheath. Owing to the fibre diameter increasing, the bundle sheath cannot contain the thicker fibres, and it bursts open. This allows increased access to the fibres, which allows better tanning, retanning, dyeing and fatliquoring. Liming (leather processing) Liming is a process used for parchment or leather processing, in which hides are soaked in an alkali solution. It