Floor coverings

A method of manufacturing a resilient floor covering including the steps of:

• laminating together in sequential order (a) a transparent or translucent wear layer, and (b) a backing layer comprising at least one backing film, whereby the film is made by:
• (i) coextruding a first polymer composition, a masking polymer composition and a third polymer composition to form a laminate to serve as a first backing film;
• wherein said masking polymer composition comprises a masking colour which minimises the visual effect of matter beneath it;
• (ii) changing the formulation of the third polymer composition to provide a new color prior to stopping the supply of colour to the formulation of the first polymer composition whereby the colour of the first coloured polymer composition is changed;
• and
• turning over the laminate so that the third polymer composition forms a face ply layer for the floor covering.

A method of reducing the amount of waste produced during continuous manufacturing of a resilient floor covering when a color in a backing film is changed, said floor covering having a wear layer and a backing layer comprising at least one backing film, the method comprising:

• co-extruding a first colored polymer composition, a first masking polymer composition, and a third colored polymer composition to form a first backing film, with said first masking polymer composition comprising a masking color which minimizes the visual effect of matter beneath it;
• changing the formulation of the first colored polymer from an original color through intermediate shades to a new color;
• and
• laminating together the wear layer and the backing layer such that (1) the first colored polymer composition is positioned between the wear layer and the first masking polymer composition and is visible through the wear layer when the first colored polymer composition is either the original or the new color;
• or (2) the third colored polymer composition is positioned between the wear layer and the first masking polymer composition so that the first colored polymer composition is not visible through the wear layer when the first colored polymer composition comprises intermediate shades.

A method of reducing the amount of waste produced when the colour of a face ply is changed in a resilient floor covering having a wear layer and a backing layer comprising at least one backing film wherein said backing film comprises a laminate of at least three polymer compositions comprising the steps of:

• supplying a first coloured polymer composition from a first hopper to a first screw extruder, melting the first polymer composition in the first screw extruder, feeding the molten first polymer composition to a feed block;
• supplying a black polymer composition from a second hopper to a second screw extruder, melting the black polymer composition in the second screw extruder, feeding the molten black polymer composition to the feed block;
• supplying a third polymer composition from a third hopper to a third screw extruder, melting the third polymer composition in the third screw extruder, feeding the molten third polymer composition to the feed block;
• combining the first coloured, the black and the third molten polymer compositions and extruding them through a die to produce a coextruded laminate having a first coloured layer a black layer and a third layer;
• changing the formulation of the third polymer composition supplied from the third hopper to the third screw extruder to provide a new colour prior to the emptying of the supply of existing formulation of the first polymer composition from the first hopper and the first screw extruder such that the colour of the third polymer is well established before the existing formulation of the first coloured polymer composition runs out;
• turning the coextruded laminate over so that the third polymer composition forms the upper layer of the backing film when used in the resilient floor covering.