| 摘要 |
<p>A process for the manufacture of building products, viz. concrete roof tiles comprising using a colourant feed means for supplying two or more colourants to a mortar mixer (18) the feed means comprising two or more supplies (52, 54, 56) of colourant and control means (62, 64, 66) downstream of said supplies for controlling in a random manner the flow and duration of flow of each colourant or colourants from each supply thereof; the colourant feed means also comprising a flow control device (61) downstream of said control means (62, 64, 66) for maintaining a flow of colourant to said mortar mixer (18) commensurate with the amount of mortar in the mixer (18). Use of the colourant feed means enables an infinitely variable range of colour blends to be obtained thereby providing the means for an enhanced range of multicoloured tiles of exceptional aesthetic appeal.</p> |
