It is common to apply labels to plastics products. These either peel off unintentionally or are deliberately removed by the purchaser. It is also known to print markings on a surface of plastics products but surface printing onto plastics materials has not proved satisfactory because it tends to rub or wear off or become faint during use of the article. Consequently, manufacturers often resort to the age-old method used for metal castings, namely engraving or embossing a negative version of the desired marking or markings onto or into the moulding tool so that the moulded product will have the desired positive version of the marking permanently formed in or on it. This method works well but is, of course, associated with the disadvantage that new expensive moulding tools have to be produced every time that the marking on the product is to be changed. This is most uneconomical for otherwise cheaply producible plastics products.

By way of example, a trade mark with which a product is marked may need to be changed by the manufacturer for the same or a different wholesale customer or an originally unregistered trade mark on the product identified by the letters TM may need to be changed subsequently to (8) to indicate registration. Again, markings indicating pending patent or design protection may need to be altered to registration markings. In many cases, the name of the merchant of a particular product may even need to be changed by the manufacturer when he sells the very same product for re-sale by a different merchant. There has therefore been a real need to devise a method and means by which otherwise relatively inexpensive moulded plastics products can be produced with markings without the need for re- tooling simply because the identification or other markings on the products need to be changed.

According to the present invention, the or each marking for a plastics product is applied to the underface of a transparent or translucent plastics marker in mirror image, the said marker being prefabricated as a member separate from the product, and the said member is subsequently moulded to the product or part thereof so that the or each marking is readable from the top of said member through the marker material and through a window formed in the product during moulding.

The invention also extends to a marker made from transparent or translucent plastics material having a marking applied to its underface in mirror image of the marking to be viewed from its top.

If, in the finished product, the underface of the marker rests on and is protected by a part of the product located beneath the aforementioned window, the marking can be applied to the underface of the marker by a simple printing process because the printing will not be exposed to wear and tear or fading. However, etching or embossing is also possible.

The invention further extends to a moulded plastics product having the aforementioned marker moulded to it to be visible through a window in the product.

A preferred example of the invention will now be described with reference to the accompanying drawings, wherein: Fig. 1 is an underneath perspective view of a marker according to the invention; Fig 2. Is a top perspective view of a moulded plastics product according to the invention incorporating a marker according to Fig. 1; and Fig. 3 is an exploded top perspective view of the Fig. 2 product.

The product as illustrated in Fig. 2 is the removable plastics lid 1 of a toddler's trainer tumbler or cup or mug (not shown). The lid 1 is made in three parts, namely first a relatively hard plastics domed lid portion 2 which is a sealing push fit or screwthreaded connection over the rim or mouth of the tumbler and can be made, for example, of polypropylene and, second, a relatively soft plastics spout portion 3 which carries a spout 5 with holes 10 and gives a soft touch to a part that comes most into contact with a child's face. The portion 3 may be a moulded thermoplastic elastomer and is moulded onto the portion 2 so as to exhibit the spout 5, a circumferential skirt 20 bonded to the rim of the lid portion 2 and an apron 21 bonded to the domed part 12 of the lid portion 2. The third part is a marker 4 of which the underface is provided with the mirror image of a trade mark 6 (Fig. 1) or merchant's name or any other marking that is intended to remain in view for as long as the product lasts. The marker can be made of a clear polypropylene. Although the marker 4 is also visible in Figs. 2 and 3, the markings on its underface have been omitted but would be visible through the transparent or translucent marker material. In fact, the top 7 of the marker is desirably convex so that it magnifies the markings on its underface.

As already mentioned, the portion 3 is moulded to the portion 2, namely by a known technique which produces a chemical water and air-tight bond between the two portions, that is to say between the skirt 20 as well as the apron 21 and the portion 2. During moulding of the portion 3 to the portion 2, the marker 4 rests on the domed lid portion 2. To ensure proper positioning of the marker on the domed portion 2 during moulding of the portion 3, the portion 2 is preferably formed with an emplacement (not shown) such as a recess moulded into the portion 2 or defined by a rib on the portion 2. The apron 21 of the lid portion 3 is moulded to trap the periphery of the marker 4 and to define a window 15 through which the markings on the marker 4 can be read. The marker 4 becomes trapped between the window surrounds, that is to say the material bounding the window 15, and the surface of the domed part 12 on which the emplacement for the marker is formed and in which the marker rests with its labelled underface. The markings 6 are therefore protected from wear.

During production, the spout 5 is moulded so as to be disposed over an aperture 11 in the portion 2 and thereby allow the flow of liquid from the tumbler to the spout holes 10. The rim of portion 2 is provided with at least one handle 13 to facilitate lifting the lid off the mouth of the tumbler or screwing the lid on and off the tumbler. Other details of the product are not really pertinent to the present invention.

It should be understood that the illustrated plastics lid is very much an example of an application of the invention to a host of possible products that are invariably marketed under different brand names or other markings but for which the same moulds can now be used, the only difference being the inexpensive transparent or translucent marker which can be of any suitable shape and bears the markings in any suitable manner, for example by printing in black or in colour.