BACKGROUND In the manufacture of car mats for example, it is known to embellis the mats by applying designs printed on fibrous felt or flock material which is secured by stitching. However, the quality of printing which can be obtained using such materials is comparatively poor, and the nature of the material does not allow the formation of intricate embossed profiles. The use of stitching can also detract from the design.

SUMMARY OF THE INVENTION The present invention provides an article comprising : - a flexible backing layer carrying a pile formed of thermoplastics material, and - a sheet of thermoplastics material superimposed on an area of the pile, said sheet being bonded to the pile by high frequency welding applied to selected areas of said sheet which are recessed into the pile during the welding process.

The invention further provides a method of embellishing an article having a flexible backing layer carrying a pile formed of thermoplastics material, comprising : - superimposing a sheet of thermoplastics material on an area of the pile ; and - bonding selected areas of the sheet to the pile by high frequency welding such that the bonded areas become recessed into the pile.

The invention thus allows high quality decorative designs to be applied which can incorporate intricate embossed shapes and profiles without prominent areas of attachment.

For the avoidance of doubt the term"thermoplastics materia !"as used herein is intended to embrace any plastics material which is softened by heat such that it can be welded using high frequency heating. Thermoplastics materials which are suitable for forming a pile include polyamide and polypropylene. In the case of the superimposed sheet material polyvinyl chloride (PVC) has been found to give consistently outstanding results in respect of welding and shaping properties, wear-resistance and general quality of finish, although other thermoplastics sheet materials may be used in some applications.

BRIEF DESCRIPTION OF THE DRAWINGS The following description and the accompanying drawings referred to therein are included by way of non-limiting example in order to illustrate how the invention may be put into practice. In the drawings : Figure 1 is a plan view of a car mat in accordance with the invention ; Figure 2 is a transverse section II-II taken through the mat of Fig. 1 ; and Figure 3 is a general view of a harness pad in accordance with the invention.

DETAILED DESCRIPTION OF THE DRAWINGS Referring firstly to Fig. 1, a small vehicle mat 1 is shown by way of example.

The mat may be of any peripheral profile and is typically edged with a fabric tape 2 which is sown or otherwise applied to the mat in known manner. As can be seen in Fig. 2, the mat has a flexible backing layer 3 of rubberised hessian or the like, which carries a pile 4 of a known thermoplastics material such as polyamide or polypropylene. By way of example, the pile may typically be up to 5mm thick and the fibres making up the pile may be cut-off or formed into loops. Mats having a deeper pile are generally of polyamide whereas polypropylene is used in shorter pile mats, both materials being waterproof and very hard-wearing.

The mat is embellished by applying a decorative design to a discreet area of the mat by means of PVC sheet 5. The sheet is relatively thin and flexible, e. g. about 0. 3mm thick. A design may be printed on the upper surface of the sheet by a conventional printing technique, leaving a margin around the design, or the sheet may be self-coloured or have a surface texture to reflect light with different colours or patterns. The sheet is bonded to the mat using a brass high frequency welding die which is shaped to correspond to the desired outline of the design. In the case of a printed design the die is placed in careful registration with the design. The die incorporates a cutting edge which, on contact with the sheet, removes marginal portions of the sheet around the design.

In addition to cutting the sheet to the shape of the design, the die is also formed such as to bond the sheet to the backing layer through the pile using high frequency energy which softens the area of the sheet in the high current regions and melts the part of the pile in contact with the said area so that the sheet and backing layer become welded together. In the case of small designs the sheet is bonded to the mat around the peripheral margin of the design as indicated by the shaded area 7 in Fig. 1, although the sheet could additionally be bonded in other areas, particularly in the case of designs which cover a large area.

Although a plain rounded rectangle is shown by way of illustration it will be appreciated that the shape could be of any desired size and profile which covers less the total upper area of the mat. A larger rectangular sheet could be applied to form a heel pad. A particular advantage of the present invention is that it allows very intricate shapes to be produced, so that small and very intricate shapes can be applied in addition to large and relatively plain heel pads. Individual letters could be formed from a single sheet for example.

In the case of a pile formed of a high melting point plastic such as polypropylene it may be necessary to interpose a thin thermoplastic bonding film between the PVC sheet and the pile to ensure that a good bond is achieved. One such material is available under the trade name"Bondex".

This adds little to the cost, and since the addition bonding layer is very thin compared with the thickness of the PVC sheet all the advantages of the invention will still be obtained.

During the welding process the non-bonded areas of the PVC sheet may also be contoured to take on an embossed shape. Since the PVC sheet material is relatively thin very intricate embossed profiles can be produced.

For example, the outline of individual letters can be raised above the non- bonded areas to make them stand out still further, e. g. the letters of the word "VIlilliams"shown in Fig. 1.

It will be noted in Fig. 2 that the embedding of the welded areas 7 into the pile results in compression of the pile behind the non-bonded areas so that the sheet is firmly supported by the pile over the entire non-bonded area, even including any narrow raised areas such as that indicated at 8 in Fig. 2.

As a result, the embossed design is strong enough to resist compression during normal use yet is still sufficiently flexible not to significantty stiffen the mat.

Fig. 3 shows a pad 10 which is also embellished by application of a design 11. The pad may be used to prevent abrasion from a seat belt or the strap of a shoulder bag for example. The pad comprises a front area 12 with a pair of opposed rearwardly-folded flaps 13 and 14 which can be secured around the belt by means of a strip of hook material 15 for example. The pad again comprises a flexible backing layer which carries a short pile (e. g. about 0. 5mm thick) of a known thermoplastics material such as polypropylene which may be formed in loops for engagement by the hook material 15. The pad is embellished by a decorative design applied using a piece of polyvinyl chloride (PVC) sheet 16. The sheet is thin and flexible, e. g. about 0. 3mm thick and is bonded by high frequency welding around the periphery of the sheet as described above. Again, marginal portions of the sheet may be removed and the sheet may be embossed during the welding process.

Articles incorporating an embellishment as set forth above are inexpensive to manufacture yet are hard-wearing and flexible. Clearly the effects which can be produced must be seen to be fully appreciated, but they represent a vast improvement on the range of embellishments which have hitherto been achieved.

It will be appreciated that the features disclosed herein may be present in any feasible combination. Whilst the above description lays emphasis on those areas which, in combination, are believed to be new, protection is claimed for any inventive combination of the features disclosed herein.