WO2003033817A1

WO2003033817A1 - Paving tile

Info

Publication number: WO2003033817A1
Application number: PCT/EP2002/011415
Authority: WO
Inventors: Jeffrey Ernest Hope
Original assignee: Jeffrey Ernest Hope
Priority date: 2001-10-11
Filing date: 2002-10-11
Publication date: 2003-04-24
Also published as: GB2380743A; GB0124458D0

Abstract

A paving tile formed of an aggregate and resin mix wherein the tile is formed to have a top surface which is aggregate-rich and bottom surface which is resinrich.

Description

PAVING TILE

The present invention relates to a paving tile or replica flagstone for a wide variety of applications, and suitable for both indoor and outdoor use.

Many methods and products are known for providing surfaces, e. g. on roads, pavements, drives, floors and other surfaces such as walls, etc. Different criteria apply, depending upon the nature of the surface required. In some cases, the aesthetic effect is important. In other cases, either instead or in addition, the durability, weather-proofing etc. of the surface is important.

Commonly, tiles or paving stones or flagstones are used to form a floor surface or to replace an existing floor surface, either where the existing surface has become worn or damaged, etc. or where a new effect is desired.

Such paving stones are available in a wide variety of materials, colours, patterns and sizes.

As floor surfaces generally have to be practical and hard-wearing, particularly those outdoors, most paving slabs and stones are made of stone. This provides a durable and weather-proof surface. Stones are available in many shapes and colours and different effects can be provided.

In order to ensure that the paving stone sits correctly and remains in place, the base onto which the stone is to be placed needs to be prepared. The surface onto which the stone is to be placed needs to be excavated to the required level. A granular fill material is then spread over the surface and compacted. A geotextile is then arranged in place, to provide stability. A bedding layer of kiln dried sand should be provided. The paving stones are then arranged in place, in the desired pattern and must then be vibrated and compacted to provide a firm, final surface . Concrete supports need to be placed around all edges, to prevent lateral spread of the paved area.

Thus, the installation of such paving requires a great deal of time and cost-consuming preparation work, by skilled labourers, in preparing the site and positioning and securing the slabs.

The aim of the present invention is to provide a paving stone which can be used to form a desired surface without the need for such time and cost-consuming preparation, and without the need for excavation, etc. of the site.

According to the present invention, in one aspect, there is provided a paving tile formed of an aggregate and resin mix, wherein the tile is formed such that the top surface is aggregate-rich relative to the bottom surface and the bottom surface is resin-rich relative to the top surface.

According to a second aspect, the invention provides a method of manufacturing a paving tile comprising pouring a mix of aggregate and resin into a mould; vibrating the mould such that one surface of the resulting tile becomes aggregate-rich relative to the other surface and the other surface is thus resin-rich relative to the first surface.

Preferred embodiments of the present invention will now be described, by way of example only, with reference to accompanying drawings. Figure 1 shows a sectional view of the preferred embodiment of the paving tile of the present invention;

Figure 2 shows a sectional view of the bottom, resin- rich surface of the tile, onto which an aggregate is broadcast to provide a mechanic bond with the adhesive;

Figures 3, 4 and 5 show different possible layouts using tiles according to the present invention.

The paving stone is in the form of a tile manufactured from a mixture of polymer resin and crushed, graded stone, sand or other aggregate. Coloured pigments may also be included to provide a desired colour or colour combination.

The tile is manufactured using a mould which may be formed with a cast surface impression to provide a desired surface appearance, including a brick appearance, cobbles, asphalt, terracotta or quarry tile surfaces, etc.

In the preferred embodiment, the edges of the tiles are serrated or, at least, not straight lines so that when the tiles are laid together, the join between adjacent tiles is less apparent. Certain tiles can be formed as border tiles, having at least one straight edge to form the boundary of the paved area.

The paving stones according to the present invention are manufactured by pouring the mixture of polymer resin and stone into a mould. The mould is then vibrated such that the stone components interlock and fall to the bottom of the mould, resulting in a stone-rich top surface of the tile when it is removed from the mould. The back of the tile, when removed from the mould, therefore is resin-rich. The preferred process of manufacture will now be described in more detail .

The paving stones are formed in a mould and are made such that as- the material is poured in to the mould, the bottom surface of the mould defines what, in the end product, will be the top surface of the tile.

The moulds used have a deep textured surface which is the negative of the upper surface finish of the paving stone. The moulds are formed such that the end product has a high slip resistance and has the visual appearance of the traditional stone being replicated, e.g. cobblestones, etc..

The paving stone is formed from an aggregate, together with coloured pigments, chopped mineral fibres and polyurethane resin mix and is preferably formed from a carefully controlled blend of up to three aggregates, having predetermined particle size, grading and hardness, together with chopped mineral fibres and polyurethane resin. This is all then mixed to a predetermined consistency.

The mixed medium is then poured in to the moulds, ensuring that mixing continues so that all aggregate particles are kept in suspension in the material, and allowing for a consistent concentration of aggregate throughout the product .

The moulds are then vibrated, preferably at a specified frequency and for a specified time interval, such that the aggregate particles interlock and migrate towards the bottom of the mould, which, in the end product, forms the upper surface of the paving stone. This stone-rich upper surface produces the required surface skid resistance. As a consequence of the aggregate components of the mixture tending towards the bottom of the mould (the top of the resulting stone) , the top of the mould, which is then the bottom surface of the resulting paving stone, is resin rich and this surface then allows a good chemical bond between the paving stone and the adhesive applied thereto, during installation.

The product is then left in the mould until it is cured to a desired consistency. Stones of a relatively large particle size are then scattered over the upper surface (which will be the bottom, resin-rich surface of the end product) , and allowed to sink in to the partially set mix. In the preferred embodiment, this large particle aggregate layer is allowed to sink up to 50 percent of its diameter in to the mix. This allows a good mechanical bond to be formed between the stone and the adhesive on installation.

The resin-rich surface thus provides a surface which ensures a good mechanical and chemical bond with an adhesive.

The tiles can then be placed onto an existing surface, by use of an adhesive, without the need to excavate or remove any existing surface. The existing surface only needs to be smoothed, if necessary, to ensure a smooth profile onto which the stones or tiles of the present invention can be laid.

The tiles are then adhered to the surface by means of an adhesive applied to the surface substrate, into which the tile is bedded. The adhesive is preferably a polymer-based adhesive which is fully compatible with the resin used in the tile material, to ensure a good chemical and mechanical bond. The preferred installation method is as follows.

The existing surface must be sound and all loose materials should be removed. The surface should be levelled by grinding off high spots and filling in low spots with, for example, mortar or other suitable compounds .

The preferred adhesive is a two-component polyurethane adhesive. Predetermined quantities of the two components are mixed together until a uniform colour is achieved and the adhesive is then spread on to the prepared surface to form a uniform adhesive layer of, for example, around 0.5mm.

The tiles are then bedded into the adhesive, before the adhesive sets (preferably within 30 minutes of mixing) . The large particle aggregate layer forms a good mechanical bond with the adhesive and the resin-rich bottom surface of the tile forms a good chemical bond.

On installation, preferably, the border tiles are put into place first, and then the area defined by them is filled in with tiles in the desired pattern.

The preferred type of stone for such tiles, due to its hard-wearing properties, is flint and the preferred type of polymer resin is polyurethane resin. However, any type of hard-wearing stone or sand material can be used and other polymer resins are also suitable.

Thus, the tile of the present invention provides an economic, hard-wearing and widely applicable alternative to existing stone paving and, in fact, laboratory tests have shown that the stones made according to the present invention last five times longer than standard concrete paving. Because of the moulding process and materials used, the stones of the present invention can be formed to replicate any type of texture or surface, e.g. cobbles, granite, brick, etc. in any composition.

Because the tile is made of a combination of stone and resin, it is, compared to existing paving slabs much lighter. The tile is relatively thin, but equally or more hard-wearing than existing paving stones.

As the laying of the tiles according to the present invention requires no excavation, preparation, etc., the tiles can be laid by unskilled persons and are, therefore, suitable for DIY use, e. g. for laying driveways etc.

Claims

CLAIMS :

1. A paving tile formed of an aggregate and resin mix, wherein the tile is formed such that the top surface is aggregate-rich relative to the bottom surface and the bottom surface is resin-rich relative to the top surface .

2. A tile according to claim 1 wherein the resin is a polymer resin.

3. A tile according to claim 1 or 2, wherein the aggregate is crushed graded stone or sand.

4. A tile according to any preceding claim further comprising coloured pigments.

5. A tile according to any preceding claim having at least one non-straight edge.

6. A tile according to any preceding claim wherein the top surface is textured.

7. A method of manufacturing a paving tile comprising pouring a mix of aggregate and resin into the mould; vibrating the mould such that one surface of the resulting tile becomes aggregate-rich relative to the other surface and the other surface is resin-rich relative to the first surface.

8. A method according to claim 7 wherein the mould has a cast surface impression to provide a textured surface appearance .

9. The method according to claim 7 or 8, comprising pouring the mixture of resin and aggregate into the mould; vibrating the mould such that the aggregate components interlock and fall to the bottom of the mould, resulting in an aggregate-rich top surface of the tile when it is removed from the mould and a resin-rich back surface of the tile when it is removed from the mould.

10. The method according to claim 9 wherein the mould is vibrated at a specified frequency for a specified time interval .

11. The method of any of claims 7 to 10 wherein the mixture is left in the mould until it is cured to a desired consistency.

12. The method according to claim 11 wherein larger particle aggregate is scattered over the mixture in the mould and sinks partially into the mixture.