Background of the invention In this specification, where a document, act or item of knowledge is referred to or discussed, this reference or discussion is not an admission that the document, act or item of knowledge or any combination thereof was at the priority date: (i) part of common general knowledge; or (ii) known to be relevant to an attempt to solve any problem with which this specification is concerned.

Thermoplastic markings are satisfactory for the bituminous surfaces for which they were designed. Such markings have quick drying times, which can be critical for the efficient movement of traffic as it leads to minimum disruption to road access.

Over the years, concrete pavement has started to be used instead of bituminous surfaces. Thermoplastic or paint markings were applied as required on the concrete surfaces in a similar manner to their use on bituminous surfaces. However, such markings were formulated for bituminous surfaces and have not performed well on concrete surfaces.

Further, maintaining these markings is difficult, and is becoming more and more expensive, since the markings have to be repainted frequently to maintain their effectiveness.

In general, repainting needs to occur every six to eighteen months depending on the usage and site condition.

The main problems associated with paint or thermoplastic markings on concrete surfaces maybe summarized as follows: 1. Poor adhesion; 2. Chaffing; 3. Rapid wear, 4. Poor skid resistance; 5. Re-application on the markings causes unevenness and weakens the adhesion;

6. Frequent re-application required to maintain the markings ; 7. Increased maintenance cost; 8. Emits toxic vapors during preparation for application ; 9. Breathing apparatus must be worn by applicators ; and 10. Pollutes the environment.

Since the cost of maintenance has been increasing, the authorities concerned with such markings are constantly looking for new methods or markings that address some of these issues.

Summary of the invention The present invention provides in one embodiment a method for forming a reflective marking on concrete and other surfaces, the method comprising the steps of coating the surface to be marked with a primer, applying a marking composition comprising a binder, a pigment and a reflective material, to the coated surface; applying a top coating to the composition following its application to the surface; and adding a layer of reflective material to the coated composition.

It has also been found that a cement based material maybe used to mark concrete and other surfaces due to its binding properties which enhances adhesion to the concrete surfaces.

The present invention accordingly provides in another embodiment a method for forming a reflective marking on concrete and other surfaces comprising applying to a surface to be marked a marking composition comprising a binder having a cement component, a pigment and a reflective material, and optionally applying a coating to the composition following its application to the surface.

In one preferred embodiment according to the invention, the layer of reflective material maybe applied to the marking composition before applying the top coating.

The present invention provides in another embodiment a method for forming a reflective marking on concrete and other surfaces, the method comprising the steps of coating the surface to be marked with a primer, applying a marking composition comprising a binder having a cement component, a pigment and a reflective material to the coated surface; applying a top coating to the composition following its application to the surface; and adding a layer of reflective material to the coated composition.

The present invention provides in another embodiment a composition for marking concrete and other surfaces, the composition comprising a binder, a pigment and a reflective material.

The present invention provides in another embodiment a composition for marking concrete and other surfaces, the composition comprising a binder having a cement component, a pigment and a reflective material.

The present invention provides in another embodiment a composition for marking concrete and other surfaces, the composition comprising a binder, a pigment, a reflective material and a polymer material.

The present invention provides in another embodiment a composition for marking concrete and other surfaces, the composition comprising a binder having a cement component, a pigment, a reflective material and a polymer material.

The present invention provides in another embodiment a composition for marking concrete and other surfaces, the composition comprising a binder, a pigment and a reflective material combined to form a pre-mix material, and a polymer material combined with the pre- mix material to form the marking composition.

The present invention provides in another embodiment a composition for marking concrete and other surfaces, the composition comprising a binder having a cement component, a pigment and a reflective material combined to form a pre-mix material, and a polymer material combined with the pre-mix material to form the marking composition.

The present invention provides in another embodiment a method for forming a reflective marking on concrete and other surfaces, the method comprising the step of applying to a surface to be marked a marking composition as described herein.

The binder may take any suitable form. In one embodiment the binder comprises cement. The cement may be a white cement. Sand may be added to the cement to form the binder. The sand is preferably a fine sand, such as a finely washed silica. The binder in the form of a cement and sand is typically combined with the pigment and the reflective material to form a pre-mix material. The pre-mix material is preferably a coherent mixture of the components forming the pre-mix.

In another embodiment the binder comprises a polymer material. The polymer material maybe combined with the pre-mix material to form a marking composition according to the invention.

The binder may comprise a mixture of one or more of cement, sand and a polymer material. These components may be combined with the pigment and the reflective material in a single stage to form the marking composition.

In one particularly preferred embodiment the binder comprises a mixture of cement and sand which is combined with the pigment and the reflective material to form a pre-mix material. The pre-mix is then blended with a polymer material to form the marking composition according to the invention.

Other binder materials and mixtures are envisaged within the scope of the present invention.

The binder maybe present in the composition in any suitable amount. When present, the cement is typically present in amounts of up to about 50% by weight, and more preferably up to about 40% by weight. When present the sand is typically present in amounts up to about 20% by weight, and more preferably up to about 16% by weight. When present, the polymer material is typically present in amounts up to about 30% by weight, and more preferably up to about 20% by weight.

The pigment may take any suitable form. The pigment is typically selected to match internationally accepted road marking colourings, namely white or yellow. A suitable pigment is titanium dioxide. That material has the advantage that it also has reflective characteristics.

Other pigments are envisaged within the scope of the present invention.

The pigment maybe present in the composition in any suitable amount. Typically the pigment will be present in amounts up to about 10% by weight to the weight of cement present in the composition, and more preferably in the range of from about 2 to about 5% by weight to the weight of cement present in the composition.

The reflective material according to the invention may take any suitable form. The material selected should have sufficient resilience and wear resistance to withstand the repeated impact of vehicles passing over it. A typical material suitable for use in the present invention is glass beads. The glass beads are preferably fine glass beads. Other reflective materials are envisaged within the scope of the present invention.

The reflective material maybe present in the composition in any suitable amount.

When present the reflective material is typically present in amounts up to about 50% by weight, and more preferably in the range of about 35 to 45% by weight.

The surface to be marked, such as a road surface, is typically prepared for the application of the marking composition by coating the surface to be marked with a primer.

The primer preferably has adhesive characteristics, and may be a material such as a paint or a flowable adhesive. This is intended to render the surface sufficiently adhesive to enable the marking composition to adhere to the surface. The marking composition is applied to the coated surface before the coating has dried. A stencil laid onto the road surface is typically used to delineate the area to be marked.

Preferably the thickness of the marking composition applied to the surface is at least about 2mm, and more preferably at least about 3mm. The thickness will generally not exceed about 8mm, and more preferably will not exceed about 5nun.

The coating of the marking composition following its application to the surface to be marked may take any suitable form. The coating will typically be for the purpose of providing a seal for the composition. The coating preferably has adhesive properties, and may be in the form of a paint or a flowable adhesive. A layer of reflective material, such as glass beads or crushed glass, maybe applied to the coating to provide the marked surface with the required reflectivity.

The present invention provides in one particularly preferred embodiment a method for forming a reflective marking on concrete and other surfaces, the method comprising the steps of: (a) coating the surface to be marked with a primer, (b) applying a marking composition comprising a binder, a pigment and a reflective material, said composition exhibiting sufficient adhesive properties to the coated surface; and (c) applying a top coating to the composition following its application to the surface, said top coating comprise a layer of reflective material ; wherein the top coating is applied directly onto the marking composition following the application of the marking composition to the surface to be marked.

The present invention provides in another particularly preferred embodiment a method for forming a reflective marking concrete and other surfaces comprising: (a) coating the concrete or other surface to be marked with a primer ; (b) applying to a surface to be marked a marking composition comprising a blend of white cement, a pigment, fine washed silica sand and fine glass beads mixed with a polymer material to form markings with a thickness in the range of from about 3mm to about 5mm ; (c) coating the marked surface with a top coat; and (d) applying a layer of glass beads to provide the required reflectivity.

Step (c) above may occur before step (d).

The present invention provides in another particularly preferred embodiment a method for marking concrete and other surfaces comprising: (a) combining white cement, a pigment, fine washed silica sand and fine glass beads to form a pre-mix material; (b) combining a polymer material with the pre-mix material to form a marking composition ; (c) coating the concrete or other surface to be marked with a primer, (d) applying the marking composition from step (b) to the coated surface to form markings having a thickness in the range of from 3 mm to 5mm ; (e) coating the marked surface with a top coat; and applying a layer of glass beads to provide the required reflectivity.

Step (f) above may occur before step (e).

Compositions according to the invention can be used to cast the required demarcation lines and directional signs to pro-long the life-span and reduce the maintenance cost of such markings.

The present invention provides in another particularly preferred embodiment a method for marking concrete and other surfaces comprising: (a) coating the concrete or other surface to be marked with a primer by use of a pressure activated spray ; (b) applying to the surface to be marked a marking composition comprising a binder, a pigment and a reflective material to the coated surface by use of a pressure activated spray, (c) coating the marked surface with a top coat by use of a pressure activated spray ; and (d) applying a layer of glass beads to provide the required reflectivity by use of gravitational machine.

One or both of the coating steps (a) and (c) above may be performed by the use of a paint roller.

Step (d) above may occur before step (c).

Investigations indicate that one or more of the following properties maybe exhibited in some formulations of the marking composition according to the invention.

1. It is easy to apply ; The marking composition can be directly applied or sprayed onto any type of surfaces i. e. concrete, bituminous, pavers, tiles, bricks etc by similar methods to those used to apply existing thermoplastic paint markings.

2. Its skid resistance is superior to that of thermoplastic or paint markings and allows the reflective markings to comply with various government standards; 3. It has good adhesion to concrete surfaces; 4. It has a longer life-span, that is, it is more wear-resistant than existing markings ; The reflective markings may last up to 4 times longer than that of known markings. Generally the expected life span of the markings according to the invention is approximately 5 years.

5. There are minimal maintenance requirements. It only requires washing off any surface dirt to retain its effectiveness;

6. It is more cost effective than existing marking compositions and methods since the need to apply fresh markings to the surface should be less frequent; and 7. It is considered to be environmentally friendly.

In comparison known thermoplastic mix markings commonly used emit toxic vapors during heating and are hazardous to health and to the environment.

8. Quick drying The initial setting of the composition will be within 5 minutes and the full cure will be approximately 30 to 45 minutes. The area could be trafficked within an hour of application.

In particular investigations indicate that some formulations of the composition according to the invention provide a permanent marking which may be readily cleaned to maintain its effectiveness in comparison to other type of markings currently used for similar applications.

The composition not only remains effective but also has'self cleansing'properties.

Due to the durability of the markings, prolonged use would expose the markings to all types of stains during trafficking. In order to remain effective and visible, some form of cleaning material may be required to remove dirt. Stains deposited on the markings can be washed away during a downpour. More stubborn stains may be easily scrubbed off. The durable nature of the markings allows it to withstand scrubbing.

Authorities concerned with the safety and maintenance of such markings are constantly placing greater emphasis on the quality and visibility of the markings. This composition for marking concrete and other surfaces provides an alternative, cost effective solution to minimize the problems associated with the markings currently applied.

Examples The invention will now be further illustrated and explained in the following non- limiting example.

Concrete surfaces were marked using the following components: 1. One part of white cement; 2. One part of pigment such as titanium dioxide grade A or yellow PP920;

3. One part of fine washed silica sand; 4. One part of fine glass beads grade A, 5. One part of organic polymer grade SS50 ; 6. One part of primer grade 780; 7. One part of top coat grade 788 ; and 8. Drop on glass beads.

The cement, pigment, sand and glass beads are mixed together and prepacked in 25 kg double ply bags.

One bag of this mixture is to be emptied into a mixer mounted onto a marking machine and combined with one liter of the organic polymer. The materials are then mixed together for at least two minutes and then discharged into a chute in the machine for application.

The surface area is coated with the primer using an RMM 100 machine designed for spraying or coating the surface with an attached roller as required depending on the site or road condition.

The cement mixture is then discharged from the machine through a stencil placed for the required road markings. The markings will have a thickness of not less than 3 mm and not exceeding 5mm.

A top coat grade 788 is then sprayed onto the markings by an air-operated RM 101 machine, followed by the application of drop-on glass beads by gravity for the required reflectorisation.

The drop-on beads are discharged onto the markings by an RM103 machine. The required index of retro-reflectivity could be obtained by adjusting and controlling the discharge of the glass beads onto the markings.

A marking formed by this method is thought to comply with the following adopted standards: 1. ASTM D4541 Adhesion to substrate 2. ASTM E303 Skid resistance test 3. BS 3262: Part 1: 1981: Skid resistance test

4. BS 3900: Part C: 1971 Hard drying time 5. BS 6044: 1987 Determination of luminance factor 6. ASTM D 4061 Determination of retroreflectance Investigations further indicate that some formulations of the composition according to the invention is that it maybe suitable and durable for the following applications due to its improved durability and enhancement of safety in most weather conditions: 1. Concrete surfaces (may last approximately 5 times longer in comparison to some known markings) 2. Bituminous surfaces (may last approximately 3 times longer in comparison to some known markings) The invention will now be further illustrated and explained in the following non- limiting example.

Concrete surfaces were marked using the following components: (a) Primer APC 53 (liquid blend) The mix formulation, known as Primer APC 53, consists of: Acrylic copolymers Algicide Thickening agent (b) Organic polymer-Filler APC 55 (liquid blend) The mix formulation, kown as Filler APC 55, consists of: Styrene-acrylate copolymers Styrene-butadiene polymers Algicide Thickening agent Deforming agent Dispersing agent (c) Top coat-APC 5 8 (liquid blend)

mix formulation, known as Filler APC 55, consists of: Vinyl toluene acrylate resin Styrene-butadine copolymers Polysiloxane based surfectant Maelic resin Low viscosity urethane pre-polymer Dispersing agent Thickening agent Algicide Defoaming agent (d) Composition of mix Silica flour/sand 600 mesh 30% White onada cement 28% Pigments 7% Glass beads 20% Gypsum powder 3% Aluminum powder 5% Activated fly ash 4% Barium sulphate 3% (e) Mixing method The reflective-mix was blended and prepacked in 25 kgs double-ply bags. One liter of Filler APC55 is added to mix 1 kilogram of reflective-mix (1: 1 ratio).

The mix is then mixed thoroughly for at least 3 minutes until a slurry is formed. A spraying device is then used to apply the required markings. The mix could also be applied by pouring the slurry into a template created for the directional arrows and leveled by using rubber or metal plate leveler.

The invention is further illustrated by the non-limiting embodiments shown in Figures 1 and 2 wherein: Figure 1 is a sequential representation of a preferred method according to the invention wherein Step (1) refers to the step of coating the concrete or other surface to be marked with a primer ; Step (2) refers to the step of applying to the surface to be marked a marking composition comprising a binder, a pigment and a reflective material to the coated surface; Step (3) coating the marked surface with a top coat ; and Step (4) applying a layer of glass beads to provide the required reflectivity.

Figure 2 is a sequential representation of an alternative method according to the invention wherein Step (1) refers to the step of coating the concrete or other surface to be marked with a primer ; Step (2) refers to the step of applying to the surface to be marked a marking composition comprising a binder, a pigment and a reflective material to the coated surface; Step (3) applying a layer of glass beads to provide the required reflectivity ; and Step (4) coating the marked surface with a top coat.

Although the figures depict directional arrows its is understood by those skilled in the art that the markings may take any suitable shape and may include markings in the shape of divider lines, pedestrian crossings, stop lines, chevron hatching, lane numbers, and continuous white lines.

The word'comprising'and forms of the word'comprising'as used in this description does not limit the invention claimed to exclude any variants or additions.

Modifications and improvements to the invention will be readily apparent to those skilled in the art. Such modifications and improvements are intended to be within the scope of this invention.