Explanatory notes
… silica. In the absence of fillers, pigments and cellular structures, hard rubber is a hard, brownish‑black (or … inflexible and inelastic and can be moulded, sawn, drilled, turned, polished, etc. Many hard rubbers acquire a highly … in other Chapters. It includes vats, troughs, articles of tubing, knife handles and knobs, grip‑handles and the like …