Flame-retardant materials

Abstract: Coloured plastics materials having flame-retardant properties include an additive comprising (a) a masterbatch containing red phosphorous and (b) a masterbatch containing one or more colouring agents. Such materials have special application as moulded seating components, eg, for seating in vehicles, stadia, theatres and the like.

Description: This invention relates to flame-retardant materials and in particular to coloured plastics materials having flame-retardant properties. Plastics materials, especially thermoplastic plastics materials, are frequently used in applications such as moulded seating components, e.g. for seating in vehicles, stadia, theatres and the like. Thus, it is imperative that such seating be made flame-retardant. In the event of a fire, many of the hitherto-used plastics materials have been found to exacerbate the fire either by their inherent flammability or, if not inherently flammable, by the evolution of toxic gases under the influence of both direct and radiant heat. Whilst it is well-known in the art to use red phosphorus either on its own or in conjunction with other additives as an effective flame-retardant, it has been recognised that there are significant deficiencies associated with said use, for example, the characteristically dull appearance of red phosphorus, and its possible adverse reactions with other colouring agents. We have now found that it is possible to incorporate colouring agents into thermoplastic plastics materials without impairing the flame-retardant effect of red phosphorus or having the available range of colours of the product restricted by the masking effect of the colour of the red phosphorus. Accordingly, the present invention provides a coloured plastics material having flame-retardant properties, characterised in that said plastics material including an additive comprising (a) a masterbatch containing red phosphorus and (b) a masterbatch containing one or more colouring agents, and in that said plastics material consists essentially of one or more polyolefins selected from the group consisting of high density polyethylene and polypropylene. Preferably, the additive may comprise from 1 to 20% by weight of the masterbatch containing red phosphorus and from 0.5 to 20% by weight of the masterbatch containing one or more colouring agents. The present application further provides a fabricated article comprising a flame-retardant plastics material as described hereinabove. The colour of the flame-retardant plastics material may be, for example, bright red, brown, black, blue or dark blue. Colours described herein are classified with reference to the RAL CHART standard, a German Standard: Farbregister Verkehrssarben. Suitably, the additive may comprise from 8 to 24% by weight of the masterbatch containing red phosphorus and from 1 to 12% by weight of the masterbatch containing one or more colouring agents. Typically, the additive may comprise 14% by weight of a masterbatch containing red phosphorus and 8% by weight of the masterbatch containing one or more colouring agents. Preferably, the plastics material may consist essentially of high density polyethylene (HDPE). Alternatively, the plastics material may consist essentially of polypropylene. The materials made according to the present invention may be adapted to be fabricated by means of a blow-moulding, compression moulding, injection-moulding or extrusion process, Fabricated articles made according to the present invention may include components for seating and panelling, e.g. for surface tops and the like. The invention will be illustrated by way of the following examples: EXAMPLES 1 TO 5 Examples 1 to 5 are formulations for flame-retardant materials imparting various hues to High Density Polyethylene (HDPE). Percentages given in the TABLE below represent the amounts of colour and of red amorphous phosphorus (by weight of the total formulation). EXAMPLES 1 2 3 4 5 Colour Bright Red Brown Black Blue Dark Blue RAL CHART REF 2002 8912 9004 5010 5011 Component % Composition HDPE 72.25 83.625 82.125 74.25 77.25 AMGARD CPC 105 14.0 14.0 14.0 14.0 14.0 COLOUR (1) - 0.5 2.0 - - COLOUR (2) 10.0 - - - - U V Stabilizer (1) - 1.875 1.875 - 3.75 U V Stabilizer (2) 3.75 - - 3.75 - COLOUR (3) - - - 10.0 - COLOUR (4) - - - - 5.0 The formulations were prepared as follows: High density polyethylene (HDPE) (a) and red amorphous phosphorus in polyethylene (b) together with one or more of components (c), (d), (e), (f), (g) and (h) [see above] were dry-blended in a high-speed blender prior to compounding in a twin-screw compounder. The compounder was maintained at 190°C for all zones and run at 150 r.p.m. The product was then blow-moulded into seat backs and bases. These were then fitted to a metal frame for testing. The flammability of the moulded articles was then assessed in accordance with BS5852 PART 5 : 1990 : Crib Standard Test No. 5, the results of which are given in TABLE 2 below: No. 5 Crib Example 1 Pass Example 2 Pass Example 3 Pass Example 4 Pass Example 5 Pass

Claims: A coloured plastics material having flame-retardant properties, characterised in that said plastics material includes an additive comprising (a) a masterbatch containing red phosphorus and (b) a masterbatch containing one or more colouring agents, and in that said plastics material consists essentially of one or more polyolefins, selected from the group consisting of high density polyethylene and polypropylene. A material according to Claim 1, characterised in that the additive comprises from 1 to 20% by weight of the masterbatch containing red phosphorus and from 0.5 to 20% by weight of the masterbatch containing one or more colouring agents. A material according to Claim 1, characterised in that the additive comprises from 8 to 24% by weight of the masterbatch containing red phosphorus and from 1 to 12% by weight of the masterbatch containing one or more colouring agents. A material according to Claim 1, 2 or 3, characterised in that the additive comprises 14% by weight of the masterbatch containing red phosphorus and 8% by weight of the masterbatch containing one or more colouring agents. A material according to any one of the preceding claims, characterised in that the plastics material consists essentially of high density polyethylene (HDPE). A material according to any one of Claims 1 to 4, characterised in that the plastics material consists essentially of polypropylene.

Inventors: AGUNLOYE FRANCIS FEMI, CHILLES COLIN ANDREW, DAVIDSON PAUL, WHELAN DECLAN NOEL, AGUNLOYE, FRANCIS 'FEMI, CHILLES, COLIN ANDREW, DAVIDSON, PAUL, WHELAN, DECLAN NOEL
Applicants: CLARIANT FINANCE BVI LTD, CLARIANT FINANCE (BVI) LIMITED
Application year: 1995
Main classification: C08K3
IPC codes: C08K5, C08L75, C08K3, C08J3, C08L23