If your 1/6 scale black pleather leather flaking,one thing you can try is to remove all the flakes and apply new layer of black adhesive silicone sealant.It takes a while for the silicone to dry,when first applied,the silicone might look shiny,wait a few minutes,and then rub the layer using the edge of a plastic spoon,or end of paintbrush to make it look matt,once it look matt,leave it to dry.Not sure if this will last long,just an experimental way of preserving toy figures with flaking leather pleather,But overall it won't look as good and smooth.
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