Producing glazed roof tile using a thin glaze layer which allows passage of gases, released from the clay tile body during firing, to form pores

摘要

Glazed roof tile (1) production uses a thin glaze layer (4) which allows passage of gases released during firing to form pores (3). A glazed roof tile (1) is produced by coating one side of a blank, formed of clay (2) containing a gas-evolving mineral, with a glaze slip layer (4) which is sufficiently thin to allow gases, released from the clay, to pass through the molten glaze layer, formed during firing, for forming pores. Independent claims are also included for: (i) a clay roof tile with a glaze layer having pores (3) connecting the tile with the atmosphere; and (ii) a glazed roof tile produced by the above process.