| 摘要 |
1324049 Coated sheet material H-J DAUSSAN 15 Sept 1971 [25 Feb 1971] 43018/71 Heading B2E [Also in Division B3] A foundry mould seal comprises a layer of compressible substance which can be destroyed by heat or fire and at least a partial coating on one side thereof of a metal-containing substance melting at or above 500‹C. The compressible substance may be smooth or corrugated paper board, moulded or dried paper pulp, or a fabric of natural or synthetic fibres. The metal-containing substance may be a metal or alloy and may be in the form of a sheet, which is glued to the compressible substance or in the form of particles which are either sprayed as molten droplets directly on to the compressible substance (where they solidify) or are solid particles, e.g. iron filings, held to a layer of binder spread on the compressible substance. Sodium silicate, phenolic resin, polyvinyl acetate and starchy substances can be used as binders. The metal-containing substance may be an oxide and a seal with a composite coating of iron filings and iron oxide is disclosed. Both sides of the compressible material may be coated. Aluminium, its alloys and alumina are also mentioned as coating materials. |
