BACKGROUND OF THE INVENTION

The invention is in the field of road markings. In particular the invention is directed to road markings having enhanced functionality.

In the art various types of road marking compositions (also referred to as road paints) are known. EP389060 discloses road paint compositions which contain granular material having a sohd core material to which dibenzoyl peroxide is bonded with the aid of a plasticizer, which is solid at room temperature. EP3055364 discloses paint compositions for marking roads for improved visibility, which comprises a high-boiling point monomer which composition is contacted with a hardener. EP0299386 discloses a prefabricated continuous road marking tape having optical and electromagnetic function, such as LEDs and electromagnetic transmitters. Tape is less suitable for large scale road marking applications, inter alia in view of the application process. Also multilayer tapes comprising electronic components is rather expensive. In situ production of road markings is not suggested or disclosed.

The present invention seeks to improve the known road marking compositions by making them more versatile, in particular by providing electronic functionality to the finished road marking. This functionality can be used e.g. in blocking or jamming cell phones which are in the vicinity of the road marking, for instance because road safety regulation would prohibit the use of mobile phones during driving.

BRIEF SUMMARY OF THE INVENTION

It is an object of the present invention to provide road marking compositions and methods of applying them that would allow using- electronic devices in the road marking. It was found that this object can be met by providing a road mark composition preferably based on a thermoplastic polymer composition, which comprises distributed therein one ore more components, which components comprise electric circuitry. Instead of paints based on

thermoplastic materials, other paints can be used as well, for instance two- component paints. Thermoplastic paints are preferred.

A further object is to provide a method of applying the marking compositions of the present invention. A suitable method in accordance with the invention comprises in situ mixing of the electric components with the molten composition that forms the paint. This mixing can be done prior to applying the paint or directly after the paint has been applied.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a schematic representation of a part of a road marking composition in accordance with the present invention.

DETAILED DESCRIPTION OF THE INVENTION

In a first aspect, the present invention is directed to a road marking composition which comprises a thermoplastic material and one or more electronic components distributed therein. As used herein, for the sake of clarity, the term road marking or road marking composition refers to the finished product (viz. the marking when applied on the road, or other surface), while the term road marking mixture refers to the starting material or to one of the starting materials. Instead of paints based on thermoplastic materials, other paints can be used as well in accordance with the present invention, for instance two-component paints.

The compositions of the present invention open up completely new applications, for instance in regulating the use of mobile phones during driving, for instance by making this use selective, e.g. all phone activity may be blocked except for calhng emergency numbers. In figure 1 a schematic representation of a part of a road marking composition in accordance with the invention is shown. This figure shows a road surface (1) to which is applied marking composition (2), which comprises a multitude of electronic components (3).

Thermoplastic road paint, also called hot melt marking paint, that can be used in accordance with the present invention is a known type of road marking paint. Thermoplastic paints (or binder systems) may be based on a binder such as hydrocarbons, rosin esters, maleic modified rosin esters (MMRE), or combinations thereof. The coatings are typically homogeneous dry mixes of the binder resin and optional ingredients, such as one or more plasticizers, glass beads (or other optics), pigments, fillers, and

combinations thereof. Thermoplastic road paints are characterized by a good durability, good reflectivity, and do not rely on volatile organic compounds as solvents. Although the present description and claims are mostly directed to thermoplastic paints, it is to be understood that other paint systems can be used in accordance with the present invention as well. Examples of other paints systems are two-component or multi-component paints.

Two-component paint typically comprises cold plastic paint and curing agent or catalyst. When marking, the two components are mixed immediately before application to form the pavement marking.

For instance methyl methacrylate (MMA) or other acrylic resins can be mixed with an organic peroxide, such as benzoyl peroxide catalyst, which may be in the form of a powder. MMA is often formulated with other methacrylates such as 2-ethylhexyl methacrylate and 2 -hydroxy ethyl methacrylate. Polymerisation (curing) is typically initiated by benzoyl peroxide.

Other two-component paints systems are based on epoxy resins which is mixed with a curing agent. Epoxy paints are typically based on a reaction between diglycidyl ether of bisphenol A (DGEBA - epoxy resin) and an amine hardener. These components react to give a film forming a crosslinked polymer. Instead of DGEBA phenol-formaldehyde resins can be used as epoxy resin, such as Novolacs (which have a formaldehyde to phenol molar ratio of less than one). Phenol -formaldehyde resins typically give a higher crosslink density.

Other two-component paints are based on polyurethane which may be either moisture cured or based on a polyol and an isocyanate.

The road marking compositions of the invention comprise one or more electronic components which may be used for instance for preventing undesired active use of mobile communication devices in cars.

The electronic components may be passive or active and can be implemented in road marking within the specification.

In view of the presence of the electronic components, application temperature is preferably between 150 °C and 200 °C.

Whereas most electronic circuits are not to be stored at such temperatures, it was found that a short exposure which is sufficient in accordance with the present invention is not necessarily harmful to the electrical circuitry.

Thus the present invention relates to a blocking or jamming device, the deployment thereof together with a road paint mixture, a device for applying such road paint mixture, and the resulting road marking.

The present invention provides an efficient means for disabling mobile telephones at a desired location and time, viz. on roads while the user of the phone is driving a vehicle. Jamming of mobile telephone signals is a well-known technique. Jamming circuits emit signals that dominate the regular mobile phone signals, making it impossible for the mobile telephone to communicate properly. Consequently, applications cannot receive or send data.

Another possibihty to block mobile telephone is to activate an application installed on the mobile device, such as mobile phone. In view of road safety, which suffers considerably from mobile devices being used while handling a vehicle, it is expected that such applications will become mandatory in the near future. In accordance with the present invention, the electronic components present in the road marking compositions participate in the exchange of signals between the mobile phone to establish or to help estabhsh that the vehicle is actually being driven, while at the same time the driver is using the mobile phone for tasks that are inappropriate, that is to say for tasks that may interfere with road safety.

For jamming of phone signals power is required. Power may be generated locally by means of induction by passing cars, photovoltaic cells, batteries, supercapacitors and combinations thereof. Another option is to incorporate one or more power lines in the road marking so that electric power is supplied from a remote source.

The mixing of the modules and the substance prior to deployment improves encapsulation of the modules and in that way, adhesion to the road.

The electronic components may be selected to have one or more of the following functions.

It may be a receiver for detecting mobile telephone activity. This enables blocking only when a mobile telephone is used, to reduce power consumption. Furthermore, this allows selection of specific frequencies or frequency ranges to block.

Another possibihty is a detector for detecting cars. This allows the device to only be active when a car passes.

Another possibihty is a recognizing non-smartphone related use, such as telephone conversations, communication by vehicle systems (to enable tracking of stolen vehicles) and emergency communication.

Another possibihty includes devices that are interconnected in parallel via two conductors. The conductors may be provided in one shielding and the wires and devices may be provided on a reel. The wire with the devices is wound off during deployment with the road marking substance.

In deploying the electronic components in combination with the road marking substance, the following considerations apply. The amount of road paint mixture and the electronic components should be matched, using mixing and dosage means. Typically the mixture and components are deployed using a deployment vehicle, the speed of which must be adjusted to the desired output, which is typically dictated by the desired thickness of the finished road marking composition.

The feed module used should ensure the electronic components are well encapsulated by means of the road marking substance to ensure proper adhesion to the road.

In case the electronic components are to be interconnected, a reel can be provided near an infeed of the substance to ensure proper

encapsulation.

The thermoplastic road marking mixture as used in the present invention typically is based on a powder mixture containing one or more, preferably all, of the following ingredients:

binder, preferably 15-25 wt.%,

glass-beads, preferably with particle sizes of 100-1500 mih, preferably in an amount of 15-40 wt.%,

antiskid silicates, preferably with particles ranging from 100 to 1500 pm, preferably in an amount of 10-25 wt.%,

fillers, preferably with particle size below 100 mih, preferably in an amount of 20-40 wt.%,

titanium dioxide, preferably in an amount of 1-12 wt.%, and the electronic components, preferably having a largest dimension 100-1500 pm, preferably in an amount of 2-25 wt.%.

To obtain the desired flow behavior the thermoplastic road marking mixture has to be heated, preferably to a temperature of 175- 190 °C. In this way a thick fluid is obtained that can be processed further. The first step is to mix the mixture to obtain the desired homogeneity. After that the mixture is ready to be applied to the road surface. When applying the mixture to the road surface the temperature is preferably 175 °C or more, because at lower temperatures the mixture generally has insufficient adhesion with the asphalt surface.

Temperature higher than above 200 °C for the mixture are not preferred because the may then decompose slowly.

The materials used in the road marking mixture preferably have a flashpoint above 230 °C.

Based on the largest particles in the thermoplastic mixture the minimum layer thickness of the applied road-marking can be determined.

Different types of application machines can be used for different kind of application methods for the thick fluid thermoplastic road-marking products.

For instance pneumatic spraying can be used. This generally requires that the application temperature of the hot thermoplastic mixture to reach more fluidity. Also the binder content percentage is generally shghtly higher with pneumatic spraying. This type of application typically results in a final sprayed layer thickness of 1000-1500 pm.

An other application type is screed application, which is suitable for a wide range of fluidities (viscosities). In this application type the road marking mixture flows through a large gap leading leads to an adjusted layer thickness of 2000-3000 pm (measured from the top of the rough surface) with a relatively flat surface.

Another application types is based on extrusion. This increasingly popular type of application uses an extruder and can be used for applying thermoplastic road-markings developed and suitable for screed application. It involves pressing the mixture through a gap of relatively small

dimensions, typically 2-3 mm, which limits the particle sizes of solids used in the product accordingly. Extrusion can be used to prepare road markings typically having a layer thickness of 2000-3000 pm.

Extruder application can also be used to form dots and/or spots. For these type of marking the binder in generally has less fluidity characteristics to avoid flowing together of the dots or spots. It requires a extruder that is designed to have gaps which are continuous opened and closed leading to thermoplastic dots or spots, typically with a height of 3-5 mm, covering up to 80% of the surface.

Typically thermoplastic road marking paint is applied as a powder. When applied as road surface markings, the road marking mixture is typically heated to 180-220 °C (preferably around 200 °C), after which it is sprayed on the road surface. Upon cooling the coating then solidifies in a typical pattern, e.g. as a road marking line. The road marking of this type is considered a thick coating, preferably of 2.7-3.3 mm thickness, more preferably between 2.7-2.8 mm. It is wear-resisting and can be made bright and reflective by using suitable additives such as glass beads.

Thermoplastic road marking mixture are fast drying and can be driven over after a few minutes, typically after 3 minutes.

Typically the molten road marking mixture is applied by extrusion using a suitable nozzle Thermoplastic markings are applied using a specially designed vehicle, know per se, see for instance EP3311976 or US2016376467. Typically the thermoplastic mix is heated to about 150 °C- 220 °C (typically around 180-200 °C) before being fed to the application apparatus.

The electronic components can be mixed with the molten composition and fed through the application apparatus, and/or it can be added by laying them onto the hot material directly (viz. within seconds, typically within 1-10 seconds) after the application of the thermoplastic before it is completely hardened. Preferably the electronic components are mixed with the molten composition, in which case components are used that are able to withstand the temperature of up to 220 °C without losing functionality.

Application of the molten road marking mixture typically involves using a screed box or ribbon gun. Immediately after the thermoplastic has been applied, other additives such as glass beads can be laid onto the hot material so that they embed before the plastic hardens. These beads provide initial

retroreflection. As the marking wears during use and the initial beads are lost, the beads mixed with the binder are uncovered, providing long term retroreflectivity. These can be given a certain thickness to produce a rumble strip effect.

The thermoplastic marking coating sets quickly. The melt adhesion of a synthetic resin makes hot-melt paint adhere strongly to the road surface. White marking paint typically contains titanium white, zinc oxide and/or lithopone.

Various additives may be present in the mixtures for use in the present invention, for instance one or more luminescent or thermochrome compounds described in EP3055364 can be added to the mixture to obtain the desired functionality. Luminescent compounds such as S1AI2O4, calcium sulfide; alkaline earth metal silicate; and combinations thereof, may be applied in the road marking mixture. Also thermochrome compounds, e.g. selected from one or more organic materials, such as thermochromic liquid crystals and thermochromic dyes; and/or transition metal compounds, may be present.

The road marking mixture of the present invention may comprise polyacrylates, in particular alkyl acrylates, and/or alkyl methacrylates, wherein preferably said alkyl group has 1 to 10 carbon atoms, more preferably 1 to 4 carbon atoms and combinations thereof. Suitable poly acrylates may further comprise styrene. The polyacrylates may be chosen from one or more homopolymers, copolymers (e.g. block copolymers, random copolymers and graft copolymers), mixtures, composites, cross- linking and blends of the above-mentioned polyacrylates. Preferably, the polyacrylate used comprises methyl methacrylate, butyl methacrylate and/or styrene and more preferably, a copolymer of methyl methacrylate and butyl methacrylate. The marking composition of the present invention may further comprise an aldehyde binder. Suitable binders which may be used include urea-aldehyde binders and/or ketone aldehyde binders, and the like.

Preferably the aldehyde binder used comprises an urea-aldehyde binder.

Typical urea-aldehyde binders which may be used comprise cyclic, straight and/or branched chain alkyl and/or alkylene aldehydes; and/or, aromatic aldehydes. Preferably, the aldehyde is selected from the group consisting of formaldehyde, benzaldehyde, propanol, hexanal, cyclohexane carboxaldehyde, acetaldehyde, butyraldehyde, valeraldehyde and

combinations thereof. The urea present in the urea-aldehyde binders may include straight and/or branched chain urea derivatives, as well as cyclic urea derivatives.

Typically, the ketone-aldehyde binders used comprise aldehydes as mentioned hereinabove. The ketone present in the ketone-aldehyde binders may include cyclic, straight and/or branched chain alkyl and/or alkylene ketones.

The marking composition of the present invention may further comprise one or more additives. Suitable additives may include fillers, accelerators (to accelerate polymerization), inhibitors, pigments, stabilizers, waxes and combinations thereof. These may be present in the road mark compositions in any suitable amount, preferably from 20-50 wt.%, more preferably from 25-30 wt.%.

Suitable fillers are inorganic materials, preferably transparent inorganic materials, such as, silicates ( e.g . glass in the form of grains, particles and/or beads, quartz, aluminium sihcate and cristobalite), aluminium oxide (e.g. corundum), calcium magnesium carbonate (e.g.

dolomite), barium sulfate, calcium carbonate, calcium sulfate, syenites and combinations thereof. The particle size of the fillers is typically from 1 mhi to 1 mm. When glass beads are used, these have a preferred diameter of 125- 625 pm. In addition larger glass beads may be used to improve the reflectivity on wet roads, in which case a diameter of more than 625 mhi, up to about 1 mm or more may be used.

Preferably the accelerators used are amine based accelerators. Such amine based accelerators may include N,N-dimethyl aniline, N,N- diethyl aniline, N,N-dimethyl-3,5-xylidine, para-(dimethylamino)- phenylacetic acid, dimethyl-para-toluidine, diethyl -para-tolui dine, ethoxylated par a-tolui dines (e.g. N,N-bis-(2-hydroxyethyl)-para- toluidine and polyethoxypar a-tolui dine) and combinations thereof.

The inhibitors used may include hydroquinone and derivatives thereof, as well as butylhydroxy toluene, para-methoxyphenol, benzene- 1,2- diol, 4-tert-butylbenzene-l,2-diol, phenothiazine and combinations thereof. Such inhibitors act to prevent thermal polymerization of the marking composition of the invention during storage.

Suitable pigments which may be used include inorganic pigments, for example, titanium dioxide, carbon black, aluminum silicate and calcium carbonate; and/or, organic pigments. The choice of the specific pigment used will be dependent on the desired color for the painted road markings.

The stabilizers which may be used include ultraviolet (UV) stabilizers, anti-settling stabilizers, or both. The UV stabilizers may be selected from one or more benzophenones, benzotriazoles, salicylates, triazines, cyanoacrylates and combinations thereof. Such UV stabilizers act to minimize discoloration and prolong the useful life of the marking composition of the invention. Suitable anti-settling stabilizers may include surfactants, colloids and/or gelling agents.

Suitable waxes may include paraffin waxes and/or crystalline polyethylene waxes. Preferably the wax used has a melting point between 50 and 120 °C.

In one embodiment the marking compositions of the invention comprises typically:

10-25 wt.% of a monomer having a high-boiling point;

5-20 wt.% of a polyacrylate and/or an aldehyde binder; 1-50 wt.% of at least one compound selected from luminescent compound; thermochrome compound; or combinations thereof; and,

20-57.5 wt.% of one or more additives.

The marking composition of the present invention may be applied to road surfaces and other horizontal surfaces ( e.g . parking lots/garages, air strips, distribution halls, sports fields and courts with a sealed surface, walkways, bicycle paths and the like) using conventional means.

The marking compositions of the present invention can be tailored such that they meet the conflicting demands that may result from their application as road markings. On the one hand the compositions need to be fast curing, which calls for a viscous liquid. On the other hand they need to be printable, which calls for a marking composition that has a very low viscosity prior to apphcation.

In accordance with the invention the method of applying a pattern on a horizontal surface comprises printing a pattern with a road marking mixture according to the present invention, followed by a step in which said printed pattern is allowed to harden, e.g. by contacting it with a hardener. This hardener initiates and propagates a polymerization reaction in which said monomer polymerizes, resulting in a cured composition, as is described in EP389060, which is incorporated herein by reference.

Preferably, the method of applying the marking composition of the present invention is according to that of EP3055364 or EP 1958517, which method comprises the steps of introducing the marking composition for dispensing into a marking composition container; applying a pressure to the marking composition which is higher than ambient pressure; carrying the marking composition to the dispensing openings; opening and closing the openings in a controlled manner per dispensing opening by means of displacing the membrane, and wherein said membrane is displaced by means of varying a medium pressure.