Above:      Ozark PD300D system at Bonar Floors during installation
Above right: PD300D dispense head incorporating Ozark MF4 valves

Colour Controller

BONAR Floors has recently commissioned an Ozark Systems PD300D print paste dispensing system at its Ripley, Derbyshire UK plant. Part of the Low and Bonar Group, the Bonar factory specialises in the production of Flotex™, a floorcovering product involving the printing of nylon 6.6 fibre pile electrostatically flocked onto the backing material. The Flotex™ backing is essentially a glass fibre and PVC composite layer to which an adhesive coating is applied. The pile is made from durable nylon 6.6 fibres precut to a standard length of 2mm and pre-dyed to the requisite wash and light-fast base colour.

Conductive
Part of this intermediate fibre dyeing process involves the fibres (known as flock) being treated to make them electrically conductive. The next stage involves the charged fibres being electrostatically applied to the backing. The flock then forms a permanent molecular bond with the base adhesive layer by discharging to earth on impact. The floorcovering is thus physically formed with a highly durable and waterproof surface that will not delaminate from the base material.

A rotary print machine is used to overprint the multicolour design onto the dyed and bonded flock web. Printing is followed by high temperature steaming to fix the pre-metallised dyes to the nylon fibres. Bonar offers commercial and domestic customers the option of a range of designs in many colourways, plus the choice of using Flotex™ as flat sheet or individual cut floor tiles.

Prior to the installation of the new Ozark Systems automatic colour kitchen, Bonar had been using a colour-tanking kitchen which involved making bulk quantities of dyes before a print run commenced. The new installation allows operatives to automatically estimate consumption of each screen colour and to dispense the components directly into plastic barrels.

Ground level
A tub ticket is produced for each finished barrel, which identifies both the recipe and the destination rotary screen. An important feature is that the whole installation is at ground level, giving much improved materials handling compared with the previous double height mezzanine arrangement.

The Ozark Systems PD300D system uses a combination of driven belt and driven stainless steel roller conveyors to transport barrels through the sequential functions. Empty barrels (of three sizes up to 250Kg capacity) are delivered in turn to the first dispense head which is fitted with six Ozark MF4 patented multi-stage dispense valves for thickeners, and then to the second dispense head for the required colorants.

The high-resolution scales used in this gravimetric system are KCC300 Mettler scales. One barrel can be receiving the colorants at the second dispense position while another barrel is accepting the maize or guar thickeners at the first dispense position. Once dispensing is complete, the conveyor moves the barrel to one of two mix stations. A twin head mix station, fitted with two 7.5hp Ozark stator/rotor mixers and two wash positions, is automatically selected for larger barrels of colour mix. Smaller barrels are automatically moved to the second mix station which is fitted with a single 5hp mixer and wash position. Once dispensed and mixed, the barrels are conveyed towards the print machine.

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Roundhill • Hollins Road • Waterhead • Oldham OL4 3SG • England
Telephone: +44 (0) 161 627 4479
Fax:            +44 (0) 161 678 8750
e-mail:        dispense@ozark.co.uk