for an Artificial Climbing Wall

Technical Field

The invention relates to improvements in or relating to a coating for an artificial climbing wall, and in particular but not exclusively, to a method of applying a coating for an artificial climbing wall.

Background

Artificial climbing walls are typically made of plywood or reinforced plastic panels. The panels may be manufactured in a factory and then transported to where the climbing wall is to be constructed. The panels are attached in-situ to a pre-constructed frame, and then climbing holds are bolted onto the panels at the required locations. A surface of the panels typically has a non-slip coating comprising a resin based mix having aggregates held in suspension within the resin, which is applied to the panels in the factory. The non-slip coating is applied and allowed to cure when the panels are horizontal. Such horizontal application and curing is required to avoid sagging of the coating as the resin cures.

Climbers typically wear climbing shoes which are made of a soft rubber compound to assist with grip. Furthermore climbers often use chalk on their hands to assist with grip. The soft rubber is usually black, which stains the artificial climbing wall over time thereby degrading its appearance. Furthermore, the chalk may also stain the wall. Such staining may be permanent, and cannot be removed by cleaning the climbing wall. It is known to re-coat an existing artificial climbing wall when in-situ. Such re-coating is usually undertaken after the climbing wall has been used for a number of years, and is required to be refurbished or refreshed. The in-situ climbing wall may be coated with a paint coating without aggregate or sand to provide a fresh appearance. The paint can become marked easily by the climbing shoes or chalk, and it may wear off quickly exposing the previous old coating of the climbing wall. Furthermore the paint may reduce the grip afforded to the artificial climbing wall because the resin and aggregate layer underneath it is covered up. Alternatively the in-situ climbing wall may be coated with a mixture of paint and sand, which is typically a non-slip floor paint whereby the sand is held in suspension within the paint. The paint can become marked easily by climbing shoes or chalk, and may wear off quickly exposing the sand, which may subsequently fall off the climbing wall and reduce the grip afforded to the artificial climbing wall. In addition, the mixture of paint and sand is difficult to paint onto a vertical or overhanging surface because the floor paint it intended to be applied to a horizontal floor. Furthermore, once applied to the vertical or overhanging surface the mixture of paint and sand may sag due to the weight of the sand, which is unsightly. Less sand may be used in the mixture of paint and sand to reduce sagging, but this may result in a reduced amount of grip for the climbing wall surface.

The non-slip floor paint is typically only available in a limited range of colours, i.e. "factory floor" colours, which may not be very attractive in appearance. Whereas it is possible to overpaint the non-slip floor paint with a further cosmetic paint finish to improve the colour or appearance, the grain size of the sand in the non-slip floor paint is typically small and will not accept a further cosmetic paint finish without reducing the grip provided by the sand. This is because the further cosmetic paint finish fills in the spaces between the sand, and has a smoothing effect on the finished climbing surface. Overall the known ways of providing the non-slip coating for an artificial climbing wall presents a significant problem regarding staining due to climbing shoes or chalk, obtaining the required texture for grip, and providing the required colour and appearance. Such problems are typically made worse when re-coating an existing artificial climbing wall in-situ, which have vertical or overhanging wall surfaces.

It is broadly an object of the present invention to address one or more of the above mentioned disadvantages of the previously known climbing wall coatings.

Summary

What is required is a climbing wall coating and a method of applying a coating for an artificial climbing wall which may reduce or minimise at least some of the above- mentioned problems.

According to a first aspect of the invention, there is provided a method of applying a coating for an artificial climbing wall, the method including:

applying a resin coat;

applying a granular material onto the resin coat when the resin coat is wet;

waiting for the resin coat to dry; and

applying a sealing coat onto the granular material and the resin coat. Such a method has the advantage that the coating is resistant to marking or staining due to the sealing coat which bonds and seals the granular material to the resin coat The Applicant has realised that the sand used on the prior art climbing wall is porous, and the soft rubber from the climbing shoes and the chalk used by climbers penetrates the sand causing the marking or staining, which may be permanent. Furthermore the Applicant has discovered that the soft rubber of climbing shoes may chemically attach the sand causing the marking or staining, and the sealing coat of the invention provides a protective layer to avoid or reduce such marking or staining. The sealing coat has the combined advantage of sealing the granular material to avoid or reduce staining, and also bonding the granular material to the resin coat It will be appreciated that the coating is a surface coating for an artificial climbing wall, and the combination of the layers i.e. coats provides an advantageous combination. Applying the granular material after the resin coat has been applied avoids the requirement to mix the granular material into the resin prior to applying it to the artificial climbing wall surface, which may be difficult to achieve when large amounts of granular material are required to be mixed into the resin. The coating of the invention is less likely to sag when applied to the artificial climbing wall surface because the resin coat is applied first and then the granular material is applied to the wet resin material. The Applicant has discovered that applying the granular material onto the wet resin material assists with drying or curing of the resin material because the granular material absorbs moisture, which also means that the coating of the invention is less likely to sag. The coating can be applied in-situ to a pre-constructed climbing wall or to panels manufactured in a factory and then transported to where the climbing wall is to be constructed. Whereas the resin coat is allowed to dry before applying the sealing coat this may include being substantially dry, and may include being cured or substantially cured. Whereas the resin coat is wet when the granular material is applied to it this may include being substantially wet, and may include being substantially uncured.

Preferably said applying the resin coat comprises applying a first resin coat and then applying a second resin coat. Preferably the second resin coat is applied when the first resin coat is wet. Preferably the first and second resin coats are the same type of resin coat. Such arrangements provide the advantage that the first resin coat acts as a base coat or primer coat for the second resin coat, and assists with coverage. Furthermore such an arrangement provides a suitable base upon which to apply the granular material.

Preferably the method includes using a pre-polymer for the resin coat. Preferably the pre- polymer is an epoxy. Such a plastics material is hard wearing, which is advantageous for the climbing wall. Furthermore, such a plastics material resists flexing, chipping and cracking which may be caused by movement of the underlying structure of the climbing wall. The method may include using a water based or a solvent based resin coat. Preferably the resin coat is thinned prior to applying it. The resin coat may be thinned with 5 to 25 % water, and in one embodiment with 10 % water. Such an arrangement provides an increased time to work with the resin coat to apply the first and second resin coats, and to apply the granular material. Furthermore, a water based resin coat is advantageous because it produces less fumes after it is applied.

Preferably said applying the granular material comprises spraying the granular material onto the resin coat Such spraying onto the wet resin coat is more readily achieved, and assists with embedding the granular material into the resin coat.

Preferably the granular material is sprayed onto the resin coat by suspending it in a stream of air. Preferably a compressor apparatus is used for spraying the granular material onto the resin coat. Preferably the compressor apparatus is operated at a low pressure within the range 20 to 50 psi (i.e. 0.14 to 0.34 MPa). Using a compressor apparatus assists with handling of the granular material, and using a low pressure avoids or reduces blowing away or removing the wet resin coat Preferably the method includes using sand or other aggregate material for the granular material. Preferably the method includes using granular material having a grit size in the range 0.1 mm to 3 mm. Such an aggregate material is readily available, and is porous which provides the advantage that the sealing coat is at least partially absorbed into it which further assists with sealing the granular material to avoid or reduce staining and with bonding the granular material to the resin coat.

Preferably the method includes applying the granular material onto the resin coat so that it has a percentage by volume of the coating of between 20 to 50 %, and in one embodiment so that it is substantially 40 %. Preferably the method further includes using a sealing coat having a low solid content. The method may further include using a water based or a solvent based sealing coat. Preferably the sealing coat is thinned prior to applying it The sealing coat may be thinned with 5 to 30 % solvent, and in one embodiment with 15 % solvent. Such an arrangement provides the advantage that the sealing coat conforms to the granular material so that it retains a degree of definition from the surface of the climbing wall to provide the required texture. Preferably the method further includes using a pre-polymer for the sealing coat Preferably the method further includes using a polyurethane for the pre-polymer. The sealing coat may be a clear or an opaque sealing coat Such a plastics material is hard wearing and also anti-marking, which is advantageous for the climbing wall. The method may include using a coloured resin coat. The method may include using a coloured granular material. The method may include using a coloured sealing coat. Preferably the method further includes using at least two of the coloured resin coat, the coloured granular material and the coloured sealing coat which are substantially of the same colour. Such arrangements help to build up a required colour for the coating, and improve the coverage thereof, which may be an advantage when covering a pre-existing artificial climbing wall. A coloured sealing coat may assist with application because it is easier to see if the granular material has been covered. Furthermore, such arrangements may provide for an improved wear of the overall coating over time. Preferably the method includes applying the coating in-situ to a pre-constructed artificial climbing wall. The method is particularly advantageous in such a situation because the Applicant has discovered that the coating resists sagging due to the resin layer and the granular material that is subsequently applied due to the drying effect that the granular material has on the resin layer when it is applied.

Preferably the method further includes applying the coating so that it has a total thickness of between 1.0 to 3.0 mm. According to a second aspect of the invention there is provided an artificial climbing wall having a coating produced using the method of the first aspect of the invention.

According to a third aspect of the invention there is provided a coating for an artificial climbing wall comprising a resin coat, a granular material on the resin coat, and a sealing coat on the granular material and the resin coat.

Such a coating has the advantage that it is resistant to marking or staining due to the sealing coat which bonds and seals the granular material to the resin coating, and provides a protective layer to avoid or reduce such marking or staining. The sealing coat has the combined advantage of sealing the granular material to avoid or reduce staining, and also bonds the granular material to the resin coat The coating can be applied in-situ to a pre- constructed climbing wall or to panels manufactured in a factory and then transported to where the climbing wall is to be constructed. Preferably the resin coat comprises a first resin coat and a second resin coat. Preferably the first and second resin coats are the same type of resin coat Such arrangements provide the advantage that the first resin coat acts as a base coat or primer coat for the second resin coat, and assists with coverage. Furthermore such an arrangement provides a suitable base for the granular material.

Preferably the resin coat is a pre-polymer. Preferably the pre-polymer is an epoxy. Such a plastics material is hard wearing, which is advantageous for the climbing wall. Furthermore, such a plastics material resists flexing, chipping and cracking which may be caused by movement of the underlying structure of the climbing wall.

The resin coat may be water based or solvent based. Preferably the resin coat is thinned prior to being applied. Such an arrangement provides an increased time to work with the resin coat to apply the first and second resin coats, and to apply the granular material. Furthermore a water based resin coat is advantageous because it produces less fumes after it is applied.

Preferably the granular material is sprayed onto the resin coat Such spraying onto the wet resin coat is more readily achieved, and embeds the granular material into the resin coat

Preferably the granular material is sprayed onto the resin coat with a compressor apparatus. Preferably the compressor apparatus is operated at a low pressure within the range 20 to 50 psi (i.e.0.14 to 0.34 MPa). The compressor apparatus assists with handling of the granular material, and using a low pressure avoids or reduces blowing away or removing the wet resin coat.

Preferably the granular material is sand or other aggregate material. Preferably the granular material has a grit size in the range 0.1 mm to 3 mm. Such an aggregate material is readily available, and is porous which provides Ihe advantage that the sealing coat is at least partially absorbed into it which further assists with sealing the granular material to avoid or reduce staining and with bonding the granular material to the resin coat Preferably the granular material has a percentage by volume of the coating of between 20 to 50 %, and in one embodiment substantially 40%.

Preferably the sealing coat has a low solid content. The sealing coat may be water based or a solvent based. Preferably the sealing coat is thinned prior to being applied. Such an arrangement provides the advantage that the sealing coat conforms to the granular material so that it retains a degree of definition from the surface of the climbing wall to provide the required texture.

Preferably the sealing coat is a pre-polymer. Preferably the pre-polymer is a polyurethane. The sealing coat may be a clear or an opaque sealing coat. Such a plastics material is hard wearing and also anti-marking, which is advantageous for the climbing wall.

The resin coat may be a coloured resin coat. The granular material may be a coloured granular material. The sealing coat may be a coloured sealing coat Preferably the coating comprises at least two of the coloured resin coat, the coloured granular material and the coloured sealing coat which are substantially of the same colour. Such arrangements help to build up a required colour for the coating, and improve the coverage thereof, which may be an advantage when covering a pre-existing artificial climbing wall. A coloured sealing coat may assist with application because it is easier to see if the granular material has been covered. Furthermore, such arrangements may provide for an improved wear of the overall coating over time.

Preferably the coating has a total thickness of between 1.0 to 3.0 mm.

According to a fourth aspect of the invention there is provided an artificial climbing wall having a coating according to the third aspect of the invention.

According to an alternative characterisation of the invention there is provided a method of applying a coating to an artificial climbing wall, the method including:

applying a resin coat;

applying a granular material onto the resin coat when the resin coat is wet, or at least partially wet;

waiting for the resin coat to dry, or at least partially dry; and

applying a sealing coat onto the granular material and the resin coat.

According to another alternative characterisation of the invention there is provided a method of applying a coating to an artificial climbing wall, the method including: applying a curable resin coat comprising a first resin coat and a second resin coat, the second resin coat being applied when the first resin coat is wet or uncured;

spraying a granular material onto the resin coat when the resin coat is wet or uncured;

waiting for the resin coat to cure or at least substantially cure; and

applying a sealing coat onto the granular material and the resin coat, the sealing coat having a low solid content so that it conforms to the granular material.

According to other characterisations of the invention there is provided a coating for an artificial climbing wall, or an artificial climbing wall having a coating according to the alternative characterisations of the invention.

Any preferred or optional features of one aspect or characterisation of the invention may be a preferred or optional feature of other aspects or characterisations of the invention.

Brief Description of the Drawings

Other features of the invention will be apparent from the following description of preferred embodiments shown by way of example only with reference to the accompanying drawings, in which;

Figure 1 shows a cross section through a climbing wall panel according to an embodiment of the invention; and Figure 2 shows a cross section through a climbing wall panel according to another embodiment of the invention; and

Figure 3 shows steps of a method according to an embodiment of the invention.

S Detailed Description

Figure 1 shows a cross section through a climbing wall panel according to an embodiment of the invention, generally designated 10. The climbing wall panel 10 comprises a sheet 12 which may be of plywood or reinforced plastic. A first coat 14 comprising an epoxy is applied to the sheet 12, for example with a roller, a brush, or by spraying. A second

10 coat 16 comprising the same epoxy is applied to the sheet 12, for example with a roller, a brush, or by spraying. Application of the first and second coats 14, 16 with a roller or a brush is more preferred than by spraying. The first coat 14 and the second coat 16 are of the same type/batch of epoxy. The second coat 16 is applied to the first coat whilst the first coat 14 is still wet. The first coat 14 being wet when the second coat 16 is applied to l 5 it may mean that the first coat 14 is partially cured. An aggregate such as sand 18 is then sprayed onto the second coat 16 whilst the second coat 16 is still wet so that the sand 18 becomes embedded, or partially embedded, in a surface of the second coat 16. The second coat 16 being wet when the sand 18 is applied to it may mean that the second coat 16 is partially cured. After the first and second coats 14, 16 have dried a polyurethane coat 20 0 is then applied over the first coat 14, the second coat 16, and the sand, for example with a roller, a brush, or by spraying. The polyurethane coat 20 is a sealing coat.

A detailed section of tile surface of the climbing wall panel 10 is shown at 22. In the detailed section the sand 18 can be seen to be embedded into the second coat 16. Furthermore the polyurethane coat 20 can be seen over the sand 18 so that the sand 18 is covered by the polyurethane 20. It is envisaged that the first coat 14 has a thickness of around 1mm, as shown at 24. It is envisaged that the second coat 16, the sand 18 and the polyurethane coat 20 has a thickness of around 1mm, as shown at 26. Alternatively the first and second coats 14, 16 have a thickness of around 1 mm, the sand 18 has a thickness of around 0.8mm, and the polyurethane coat 20 has a thickness of around 0.2mm to provide an overall thickness of the coating 14, 16, 18, 20 of about 2mm. Alternatively the overall total thickness of the coating 14, 16, 18, 20 may be between 1.0 to 3.0 mm. The second coat 16 is applied to the first coat 14 when the first coat 14 is still wet. This may be, for example, after about 10 to 20 minutes after applying the first coat 14. The benefit of applying the first coat in this manner is that the first coat 14 acts as a base coat or primer coat to provide a surface pre-treatment to the sheet 12. The sheet 12 may absorb moisture from the first coat 14 when applied. After the second coat 16 is applied it remains wet for an increased period of time and accepts the sand 18 more readily. The second coat 16 acts as a tack coat to accept the sand 18. This 'double-coat' technique allows for the first coat 14 to partially dry out whilst retaining sufficient moisture so that the second coat 16 becomes very tacky and supports the sand 18. Another advantage is that any runs and drips from the initial application of the first coat 14 can be over-rolled or brushed with the second coat 16. Overall the 'double-coat' technique provides good and even coverage for the sheet 12.

Figure 2 shows a cross section through a climbing wall panel according to another embodiment of the invention. In Figure 2 like features to the arrangements of Figure 1 are shown with like reference numerals. In Figure 2 it can be seen that the epoxy comprises only the first coat 14, and the sand 18 is applied to the first coat 14. The first coat 14 is then allowed to cure and then the polyurethane coat 20 is applied to cover the sand 18. The first coat 14, the sand 18 and the polyurethane coat 20 has a thickness of around 2mm, as shown at 28, and may be between 1.0 to 3.0 mm. Application of the first coat 14 with a roller or a brush is more preferred than by spraying.

Referring to Figure 1 and 2, the epoxy of the first and second coats 14, 16 is a two-part epoxy (e.g. an adhesive epoxy), also known as a two-pack epoxy, comprises an epoxy resin and a hardener or curative, which are mixed together to react them prior to application to the sheet 12. The epoxy has a relatively high viscosity prior to application to the sheet 12. A suitable epoxy is PROFLOOR two-pack epoxy (Ref. W/222) manufactured by COO-VAR. It is also envisaged mat the epoxy may be a single-part epoxy, which is reacted with itself. In either case the epoxy is of the epoxide functional group, also known as polyepoxides, whereby the epoxy resin is a reactive pre-polymer or polymer which contain the epoxide groups. It will be appreciated that the curing process of the epoxy relates to the cross-linking reaction, which is commonly referred to as curing so that the epoxy becomes dry. It is envisaged that the epoxy resin may be of a low molecular weight pre-polymer or a higher molecular weight polymer. The epoxy resin selected has a molecular weight number average of less than or equal to 700, and it is envisaged that a range of between 600 to 800 might also provide the required results. In other words, the epoxide content of the first and second coats 14, 16 has an epoxide number of between 600 and 800, and in a preferred embodiment 700. The epoxy is a resin, which is a plastic, and more specifically a thermoset plastic, and the term pre- polymer refers to a monomer or system of monomers that have been reacted to an intermediate molecular mass state, which is capable of further polymerization by reactive groups to a fully cured high molecular weight state. The first and second coats 14, 16 may be termed a first resin coat and a second resin coat.

The epoxy of the first and second coats 14, 16 may be solvent, oil or water based. The water based epoxy is preferred because it produces less fumes after it is applied. In the embodiments of Figures 1 and 2 the epoxy of the first and second coats 14, 16 was thinned with water prior to applying it so that it remained wet for longer and to allow suficient time to apply the sand 18, and the second coat 16 in the case of the embodiment of Figure 1. Typically the first and second coats 14, 16 were thinned by the addition of about 10% water, and it is envisaged that such thinning could be in the range 5 to 25% whilst still providing the required effect. The thinning of the epoxy provides for a longer period of time to apply the first and second coats 14, 16, and to apply the sand 18. The water based epoxy is preferred because it can be thinned more easily that a solvent based epoxy. Typically with the water based epoxy there is a time window of around 2 to 4 hours to apply it, and to spray sand 18 onto it before the epoxy begins to cure.

Use of the first and second coats 14, 16 as per the arrangements of Figure 1 provides a progressive epoxy layer of a single epoxy type, which adheres well to the sheet 10 and also allows the correct amount of sand 18 to be applied and bond to the epoxy. Applying the epoxy in this manner reduces the epoxy material required, for example by around 50% when compared to applying a single coat 14 as per the arrangements of Figure 2. Whereas the use of dry sand 18 has been described above it will be appreciated that the sand may be any other suitable particulate material, granular material or aggregate matter, such as a grain or grit with the proviso that it is hard-wearing. Such a material will be described herein as being a granular material. The granular material is preferably dry. The granular material may be a synthetic material such as slag, aluminum oxide, silicon carbide or carborundum, glass beads, ceramic shot, glass grit. Alternatively, the granular material may be a naturally occurring material such as crushed nut shells or fruit kernels. Typically the granular material has a grit size, i.e. a dimension or across a depth, width or length thereof, in the region of 0.1 mm to 3 mm. It is envisaged that the sand 18 may be present in a percentage by volume in the overall coating of between 20 to 50 %, and preferably around 40%.

In the embodiments herein the sand 18 is applied by spraying it onto the wet epoxy once or twice to obtain the required coverage. The sand 18 is applied using a conventional sand blaster apparatus which is operated at a relatively low pressure to provide a fine flow of sand 18 so that it covers the epoxy evenly. Typically when sand blasting a surface to abrade it a high pressure is recommended whereby a compressor of the sand blaster apparatus may be operated at a pressure having a minimum of 80 to 100 psi (i.e. 0.55 to 0.69 MPa). The sand blaster apparatus may alternatively be termed a compressor apparatus. In the embodiments herein the compressor is operated at a lower pressure of 35 psi (i.e. 0.24 MPa). Such a pressure avoids or reduces the possibility of blowing the epoxy away from the surface whilst also embedding the sand 18 sufficiently into the coats 14, 16. Furthermore, using such a low pressure reduces wastage of the sand 18. It is envisaged that compressor could be operated at a pressure in the range 20 to 50 psi (i.e. 0.14 to 0.34 MPa) and still provide the required results. It will be appreciated mat sand is suspended in a stream of air when it is sprayed onto the epoxy.

The sand 18 is a pre-prepared sand that is washed and dried in a kiln before applying it to the coats 14, 16. In one embodiment the sand 18 is dyed, i.e. coloured, before applying it to the epoxy. Sand is porous and will accept colouring, and can be dyed in most colours e.g. white, black, green or other colour. The Applicant has found that good coverage of the required colour is obtained when the sand 18 and the epoxy are of the same colour, or substantially the same colour, which helps to build the base and thickness of the colour. Artificial climbing walls panels 10 prepared in the manner have a strong and solid colour preparation.

The Applicant has also discovered that applying the sand 18 onto the wet coats 14, 16 assists with drying or curing thereof, which also means that the coating 14, 16, 18, 20 is less likely to sag. The sand 18 tends to dry the coat 14, 16 on contact because the sand 18 is porous and absorbs moisture from the coats 14, 16. In other words the coats 14, 16 begin to cure on contact with the sand 18, which assists with reducing sagging. Such an arrangement may also assist with reducing the amount of sand 18 that is wasted when applying it because when the coats 14, 16 have accepted a sufficient amount of sand 18 no more sand 18 will typically stick to the coats 14, 16. This means that the operator of the spraying apparatus can stop applying the sand 18 when they can see that such a point has been reached. Such an arrangement also avoids the application of too much sand 18, which may adversely mean that the coats 14, 16 may not be able to breathe and cure correctly. The fact that the climbing wall panel 10 is vertical when the sand 18 is applied also assists with applying the required amount of sand 18, because any excess sand 18 falls away from the panel 10.

The polyurethane coat 20 is a two-part polyurethane resin, also known as a two-pack polyurethane, which may be solvent or water based. A suitable polyurethane 20 is P101 water based two-pack polyurethane manufactured by COO-VAR. The polyurethane coat 20 is a sealing coat which seals the sand 18 onto the epoxy and helps the sand 18 to stick to it. The polyurethane resin has a low solid content, i.e.47%, and a high solvent or water content which evaporates after being applied to the sand 18. This has the advantage that the finished polyurethane coat 20 conforms to the coating of sand 18 so that it retains a degree of definition from the surface. Furthermore, the polyurethane is partly absorbed into the sand 18 because the sand 18 is porous. Such absorption assists with bonding of the polyurethane coat 20 to the sand 18. Typically the wet film thickness of the polyurethane coat 20 is in the region of 120 to 135 microns, and the dry film thickness of the polyurethane coat 20 is in the region of 65 to 75 microns.

In one embodiment the polyurethane coat 20 may be thinned with solvent or water prior to applying it to the artificial climbing wall panel 10, for example, thinning by the addition of about 15% or solvent or water. It is envisaged that such thinning could be in the range 5 to 30% whilst still providing the required effect. It will be understood that the polyurethane coat 20 is a polymer or pre-polymer, which is a thermosetting plastic, although use of a thermoplastic polyurethane is also envisaged. TTunning the polyurethane coat 20 makes it less viscous and may help to provide the required distribution of the relatively thin coating provided by the polyurethane coat 20. The polyurethane coat 20 provides the advantage that rubber marks from climbing shoes, and chalk marks used for assisting grip can be readily wiped or brushed off. The Applicant has discovered that the soft rubber of climbing shoes may chemically attach the sand because it is porous, and the polyurethane coat 20 provides a protective layer. Such a polyurethane coat 20 may have a low surface energy which inhibits anything from being stuck to it. The polyurethane coat 20 is clear, i.e. transparent or partially transparent, so that the colour of the sand 18 and the epoxy can be seen through it. Furthermore, use of the clear polyurethane coat 20 permits easier cutting in between adjacent artificial climbing wall panels 10 which have a different colour.

In an alternative arrangement the polyurethane coat 20 is opaque or substantially opaque, and is of a colour that is the same as or substantially the same as the epoxy and/or sand 18. Such an arrangement improves the manner in which the colour of the artificial climbing wall panel 10 is built up. For example, when using white sand 18 a polyurethane coat 20 which is white in colour may be used, which provide a brighter finish than using a clear polyurethane coat 20. Such an arrangement may work particularly well if the coating 14, 16, 18, 20 is applied over a pre-existing artificial climbing wall that has an old surface covering having a dark colour. Furthermore, using a coloured polyurethane coat 20 rather than a clear polyurethane coat 20 means that it is easier to see if the sand 18 has been covered. A suitable coloured polyurethane PI 01 two-pack polyurethane manufactured by TEAM AC. In one embodiment the sand 18 is overpainted with artwork such as graffiti artwork prior to applying the polyurethane coat 20. When such artwork is applied the water based polyurethane coat 20 is used to avoid or minimise degrading of the artwork. Whereas use of a polyurethane coat 20 has been described it will be appreciated that any sealing coat may be used with the proviso that it seals the sand 18, and provides an anti- marking coating. It is envisaged that a varnish or lacquer may be used mat dries by solvent or water evaporation or a curing process to produce a hard and durable finish. Alternatively a paint or thinned paint may be used as the sealing coat with the proviso that the paint is an anti-marking coating. Such an anti-marking coating may be termed an anti-graffiti coating, i.e. the sealing coat is an anti-graffiti coating.

The arrangements of Figures 1 and 2 show a new climbing panel 10, which has not been previously coated or painted. The new climbing panel 10 may be coated when the panel is produced in a factory, or in-situ on a newly built artificial climbing wall. Alternatively, the coating 14, 16, 18, 20 may be applied over the surface of an existing artificial climbing wall, which has old paint or an old coating that is required to be re-surfaced or refreshed. The embodiments herein provide a textured surface for a new or old artificial climbing wall. A further benefit of using the epoxy resin on such an in-situ climbing wall is that it hard wearing, and resists flexing, chipping and cracking which may be caused by movement of the underlying structure of the climbing wall i.e. the underlying plywood, which may shrink or grow over time. Figure 3 shows steps of a method according to an embodiment of the invention, generally designated 30. It will be appreciated that the steps may be performed in a different order, and may not necessarily be performed in the order shown in Figure 3. The method 30 of applying a coating for an artificial climbing wall includes applying a resin coat 14 as shown at 32, applying a granular material 18 onto the resin coat 14 when the resin coat is wet, as shown at 34, waiting for the resin coat to dry, as shown at 36, and applying a sealing coat 20 onto the granular material 18 and the resin coat 14, as shown at 38.

Said applying the resin coat 14 comprises applying a first resin coat 14 and then applying a second resin coat 16, as shown at 40. The method includes applying the second resin coat 16 when the first resin coat 14 is wet, as shown at 42. The method includes using the same type of resin coat for the first and second resin coats 14, 16.

The method includes using a pre-polymer for the resin coat 14, 16. The method includes using an epoxy for the pre-polymer. The method includes using a water based or a solvent based resin coat 14, 16. The method includes thinning the resin coat 14, 16 prior to applying it, as shown at 44. The method includes thinning the resin coat with 5 to 25 % water, and preferably with 10 % water. Said applying the granular material 18 comprises spraying the granular material 18 onto the resin coat 14, 16, as shown at 46. The method includes spraying the granular material 18 onto the resin coat 14, 16 by suspending the granular material 18 in a stream of air. The method includes using a compressor apparatus for spraying the granular material 18 onto the resin coat 14, 16. The method includes operating the compressor apparatus at low pressure within the range 20 to 50 psi (i.e. 0.14 to 0.34 MPa).

The method includes using sand or other aggregate material for the granular material 18. The method includes using granular material 18 having a grit size in the range 0.1 mm to 3 mm. The method includes applying the granular material 18 onto the resin coat 14, 16 so that it has a percentage by volume of the coating of between 20 to 50 %, and preferably substantially 40%. The method includes using a sealing coat 20 having a low solid content. The method includes using a water based or a solvent based sealing coat 20. The method includes thinning the sealing coat 20 prior to applying it. The method includes thinning the sealing coat with 5 to 30 % solvent, and preferably with 15 % solvent. The method includes using a pre-polymer for the sealing coat 20. The method includes using a polyurethane for the pre-polymer. The method includes using a clear or an opaque sealing coat 20.

The method includes using a coloured resin coat 14, 16. The method includes using a coloured granular material 18. The method includes using a coloured sealing coat 20. The method includes using at least two of the coloured resin coat 14, 16, the coloured granular material 18 and the coloured sealing coat 20, which are substantially of the same colour. The method includes applying the coating in-situ to a pre-constructed artificial climbing wall. The method includes applying the coating so that it has a total thickness of between 1.5 to 3.0 mm. Whereas the term climbing wall has been used it will be appreciated that the climbing wall may be vertical or at an angle, and may comprise an overhang. The non-slip surface of the embodiments herein provide a texture to the artificial climbing wall surface or panel which may be vertical, horizontal or have an overhang.