Lime wash is not suitable for cargo like Sulphur loading

Lime wash does not stop the acid attack on steel plates as hard sulphur easily penetrates the soft lime wash and is not suitable for sulphur. And another limitation of lime wash on the ship is Lime wash is always applied to a dampened surface (use a small hand-pumped spray) rather than directly to a dry substrate. It should not be applied in very cold, hot or wet conditions. It is also essential to wear protective gloves and goggles. 

Slip Barrier Coat Hold Block contains polymer which forms inert polymer and unreactive layer between cargo hold surface and Sulphur. Pentration through hard sulphur edge on Polymer film is absolutely not possible, this is the reason why, the use of SLIP Barrier coat is more effective against protection of hazardous cargo.
And another rumour behind lime coating and lime wash ( Traditional Method ) is more economical and approximately costs 1000 US$ only. While slip Barrier coat's unit price is approx 1.5 US$ / Ltr. Here I want to clarify that total costing of slip Barrier coat for 5 Hold can be minimized upto 1000 US$, As this product is highly concentrated and can be diluted with fresh water before the  application. And its using procedure is also very simple, as it can applied through a simple sprayer machine or by brush.