EP4041951B1 - Illuminating panel integrated into a traversable surface - Google Patents

Description

Technical Field

The present invention relates to the technical field of functionalized trafficable roads, in particular with luminous elements.

Prior art

In the above field, it is known to integrate into commercial devices active elements such as light-emitting diodes (LEDs), energy storage and a current source, for example a photovoltaic element. These devices generally have a significant thickness which makes them unsuitable for use on a large surface, and an elementary size which does not exceed ten centimeters and is intended for point delimitation.

Devices comprising light elements requiring embedding in the roadway are also known, for example, which may comprise the light elements within a matrix several centimetres thick. These devices are difficult to integrate into existing roadways.

It would be advantageous to have devices incorporating light elements, which can be integrated into an existing trafficable road without embedding, allowing a large surface area to be covered, integrating with existing road markings, and whose switching on would allow the desired patterns to be formed, for example by remote control.

The request FR3063128 describes a luminous signaling panel comprising a multi-layer structure and light-emitting diodes (LEDs) in the form of LED strips. Given the nature of the materials used for the different layers and their arrangement, the mechanical strength and/or weather resistance properties of the panel can be improved. In addition, when the panel comprises several LED strips, these must be connected by means of welds, which both represent potential weak points in terms of mechanical strength and complicate the manufacture of the panel.

In this context, the Applicants have developed a light panel making it possible to overcome the shortcomings of previous devices, the panel comprising interconnected luminous elements, having high thermomechanical stability, which can stick to the surface of the roadway by integrating with the existing markings, and which can be used to display a wide variety of patterns in terms of shape, size and color in particular.

Statement of the invention

• un premier film de protection, disposé en face avant de la dalle lumineuse, en un premier matériau,
• un premier film encapsulant extérieur, en un deuxième matériau,
• un film encapsulant intérieur, en un troisième matériau,
• un deuxième film encapsulant extérieur, en un quatrième matériau,
• un deuxième film de protection, disposé en face arrière de la dalle lumineuse, en un cinquième matériau,

• l'un des films choisis parmi le premier film encapsulant extérieur, le film encapsulant intérieur et le deuxième film encapsulant extérieur enrobant au moins un élément actif adapté pour émettre de la lumière,
• chaque élément actif adapté pour émettre de la lumière comprenant au moins un élément lumineux sur un support permettant de l'alimenter,
• le premier matériau, le deuxième matériau, le troisième matériau, le quatrième matériau et le cinquième matériau ayant, respectivement, des modules d'Young E₁, E₂, E₃, E₄ et E₅ et ayant, respectivement, des coefficients de dilatation thermique CTE₁, CTE₂, CTE₃, CTE₄ et CTE₅,
• E₁ et E₅ étant semblables ou identiques, E₂ et E₄ étant semblables ou identiques, E₁>E₂ et E₄<E₅,
• CTE₁ et CTE₅ étant semblables ou identiques, CTE₂ et CTE₄ étant semblables ou identiques,
• CTE₁<CTE₂ et CTE₄>CTE₅.

The first object of the invention is a luminous slab, in particular capable of being integrated into a trafficable roadway, comprising successively:

• a first protective film, placed on the front of the light panel, made of a first material,
• a first outer encapsulating film, made of a second material,
• an inner encapsulating film, made of a third material,
• a second outer encapsulating film, made of a fourth material,
• a second protective film, placed on the back of the light panel, in a fifth material,

• one of the films selected from the first outer encapsulating film, the inner encapsulating film and the second outer encapsulating film coating at least one active element adapted to emit light,
• each active element adapted to emit light comprising at least one luminous element on a support allowing it to be powered,
• the first material, the second material, the third material, the fourth material and the fifth material having, respectively, Young's moduli E ₁ , E ₂ , E ₃ , E ₄ and E ₅ and having, respectively, coefficients of thermal expansion CTE ₁ , CTE ₂ , CTE ₃ , CTE ₄ and CTE ₅ ,
• E ₁ and E ₅ being similar or identical, E ₂ and E ₄ being similar or identical, E ₁ >E ₂ and E ₄ <E ₅ ,
• CTE ₁ and CTE ₅ being similar or identical, CTE ₂ and CTE ₄ being similar or identical,
• CTE ₁ <CTE ₂ and CTE ₄ >CTE ₅ .

By "similar" is meant in the present invention that the values do not differ by more than 30%, preferably by no more than 20%, in particular by no more than 10%. Advantageously, the values are identical.

• un gradient de module d'Young en U : décroissant depuis le premier film de protection (face avant) jusqu'à la couche d'encapsulant extérieur et avantageusement jusqu'à la couche d'encapsulant intérieur, puis croissant depuis la couche d'encapsulant extérieur, avantageusement depuis la couche d'encapsulant intérieur, jusqu'au second film de protection (face arrière) ;
• un gradient de coefficient de dilatation thermique en U inversé : croissant depuis le premier film de protection (face avant) jusqu'à la couche d'encapsulant extérieur et avantageusement jusqu'à la couche d'encapsulant intérieur, puis décroissant depuis la couche d'encapsulant extérieur, avantageusement depuis la couche d'encapsulant intérieur, jusqu'au second film de protection (face arrière) ;
• des propriétés thermomécaniques (module d'Young et coefficient de dilatation thermique) symétriques ou quasi symétriques par rapport à la couche centrale de l'empilement de couches, c'est-à-dire la couche d'encapsulant intérieur. Cette symétrie ou quasi-symétrie assure que les contraintes éventuellement présentes au sein de l'empilement de couches s'annulent deux à deux par effet miroir, garantissant une bonne stabilité thermomécanique de l'ensemble.

The layers of the luminous slab according to the invention form a stack which presents:

• a U-shaped Young's modulus gradient: decreasing from the first protective film (front face) to the outer encapsulant layer and advantageously to the inner encapsulant layer, then increasing from the outer encapsulant layer, advantageously from the inner encapsulant layer, to the second protective film (back face);
• an inverted U-shaped thermal expansion coefficient gradient: increasing from the first protective film (front face) to the outer encapsulant layer and advantageously to the inner encapsulant layer, then decreasing from the outer encapsulant layer, advantageously from the inner encapsulant layer, to the second protective film (back face);
• thermomechanical properties (Young's modulus and coefficient of thermal expansion) that are symmetrical or quasi-symmetrical with respect to the central layer of the stack of layers, i.e. the inner encapsulant layer. This symmetry or quasi-symmetry ensures that any stresses present within the stack of layers cancel each other out two by two by mirror effect, guaranteeing good thermomechanical stability of the whole.

An assembly with such thermomechanical characteristics has a flat appearance that can be maintained over a wide temperature range, including -40°C to +85°C. This range encompasses all or almost all of the temperatures to which roads may be exposed.

The number, nature and/or relative position of the active elements in the panel can be adapted so that the light emitted by the light panel forms a desired pattern.

Subsequently, even if the description refers to a light panel comprising LEDs mounted on a printed circuit, the invention can be transposed to any active element suitable for emitting light and whose dimensions allow it to be incorporated into the films of the light panel of the present invention.

The first protective film and/or the second protective film allow the mechanical protection of the light panel, in particular the active elements of the light panel. Advantageously, the Young's moduli E ₁ and/or E ₅ of the first and/or the fifth materials are independently greater than 2 GPa, preferably greater than 5 GPa and even more preferably greater than 10 GPa. Advantageously, the thermal expansion coefficients CTE ₁ and/or CTE ₅ of the first and/or the fifth materials are independently less than 200×10 ^-6 /K, preferably less than 100×10 ^-6 /K and even more preferably less than 50×10 ^-6 /K.

The active elements are mechanically protected, in particular in the event of mechanical impact or the presence of a heavy load on the device, in particular after application on a trafficable roadway. By way of illustration and not limitation, mechanical impacts may be punching by the rear face of the device (by roughness of the underlying trafficable roadway); punching by the front face of the device due to traffic; mechanical shock on the front face (for example by the impact of hailstones or falling objects); compression of the device by the front face due to traffic, the presence of dead weight, or a falling mass; shearing. The active elements are not degraded, their performance and/or their functionalities remain intact. In particular, this avoids damaging and/or reducing the brightness of the active elements.

Unless otherwise stated, Young's modulus and thermal expansion coefficient values are given at room temperature of 20 to 25°C.

The first and fifth materials may be, independently of each other, any material suitable for mechanically protecting the light panel, in particular the active elements suitable for emitting light which it contains.

The first material must also be at least partly translucent, or even transparent, in order to allow at least part of the light emitted by the active elements to pass through. In certain embodiments, the first protective film may be made opaque in certain areas in order to allow the passage of the light emitted by the active elements to form a desired pattern. For example, certain areas of the first protective film may be painted, in a stencil manner, to modulate the transmission of light through these areas, for example to make them opaque. This makes it possible in particular to produce, by masking, the illumination of specific patterns such as pictograms in particular without having to produce specific electronic circuits.

Advantageously, the first and fifth materials are identical. The first and/or fifth materials may in particular independently comprise a resin such as an acrylic resin, in particular a Verniroc base, an epoxy resin or a polyurethane resin. The dosage of the resin may be between 10 g/m ² and 1000 g/m ² , better still between 30 g/m ² and 700 g/m ² , ideally between 150 g/m ² and 600 g/m ² .

The first and fifth materials may further comprise a colored substance such as a white Griffon road paint, TiO ₂ pigments or a yellow paint.

The first material may further comprise transparent or colored texturizing elements, for example glass grains and/or beads, of a size of for example between 0.01 mm and 4 mm, better between 0.1 mm and 2 mm, ideally between 0.2 mm and 1.8 mm. The dosage of these glass grains and/or beads may be between 10 and 800 g/m ² , better between 30 and 500 g/m ² , ideally between 50 and 400 g/m ² . The colorimetry may be measured according to the NF EN 1436:2018 standards, and fall within the RGB scope of a marking, for example the NF EN 1436+A1 standard for a white road marking. Such dosages ensure an adhesion that can be measured according to the NF EN EN13036-4 standard with the SRT pendulum, and provide a value greater than 0.45 and ideally greater than 0.55. These same dosages prevent any excessive material departure, assessed with Wehner & Schulze type polishing or adhesion machines, or traffic simulators such as rutting machines.

The fifth material may comprise a resin selected from the group consisting of an epoxy resin with added glass fibers, a polypropylene resin, a polyethylene resin and a polyethylene terephthalate resin optionally with added fibers.

The first and/or fifth materials may comprise a composite comprising glass fibers and an epoxy resin.

The thickness of the first protective film and/or the second protective film may independently be between 0.1 mm and 5.0 mm, more preferably between 0.25 mm and 3.0 mm, preferably between 0.4 mm and 1.5 mm, ideally between 0.5 mm and 1.0 mm. In a particular embodiment, the thickness of the first and/or second protective film is substantially 400 µm (micrometers).

The first protective film may include a transparent or translucent resin and irregular texturizing elements providing a certain adhesion, including in humid conditions.

The second protective film may include at least one hole allowing the passage of the electrical power supply between the exterior of the panel and the active elements. In certain embodiments, this hole may be at least partially filled by the third material (of the inner encapsulating film).

The first encapsulating film and/or the second outer encapsulating film provide mechanical and, above all, water protection for the active elements. Advantageously, the Young's moduli E ₂ and/or E ₄ of the second and/or fourth materials range independently from 100 to 800 MPa, and preferably from 200 to 600 MPa.

Advantageously, the water vapor transmission rates known by the acronym WVTR (Water Vapor Transmission Rate) of the second and fourth materials are as low as possible. In particular, the water vapor transmission rates of the second and/or fourth materials are, at room temperature of 20 to 25°C, less than 10 ^-4 gm ^-2 .d ^-1 , preferably less than 10 ^-5 gm ^-2 .d ^-1 .

Advantageously, the thermal expansion coefficients E ₂ and/or E ₄ of the second and/or fourth materials are independently between 200.10 ^-6 /K and 700.10 ^-6 /K, and preferably between 300.10 ^-6 /K and 600.10 ^-6 /K.

The second and fourth materials may be, independently of each other, any material suitable for water-protecting the active elements of the light panel. Advantageously, the second and fourth materials are identical.

The thickness of the first outer encapsulating film and/or the second outer encapsulating film may independently be between 0.25 mm and 2.0 mm, preferably between 0.25 mm and 1.0 mm.

The inner encapsulating film has the role, when it coats the active elements, of mechanically protecting them, in particular by filling the volumes between the active elements which are not necessarily contiguous. Advantageously, the Young's modulus of the third material E ₃ ranges from 5 to 100 MPa, and preferably from 10 to 50 MPa. Advantageously, the coefficient of thermal expansion CTE ₃ of the third material is between 800.10 ^-6 /K and 2000.10 ^-6 /K, preferably between 800.10 ^-6 /K and 1400.10 ^-6 /K.

The third material may be any material suitable for mechanically protecting the active elements. The thickness of the inner encapsulating film may be between 0.4 mm and 2.0 mm, preferably between 0.8 mm and 1.4 mm.

The second, third and fourth materials may be independently selected from the group consisting of thermal polyolefins such as that known under the name CVF, ethylene vinyl acetate (EVA), thermoplastic polyurethane TPU, an ionomer, a polycarbonate and an acrylic resin. The second and/or fourth materials may in particular be independently an ionomer, such as that marketed under the name lonomer DG3 by the company Juraplast. The third material may in particular be a thermoplastic polyolefin or a (meth)acrylic resin.

In one embodiment, the first and fifth materials are identical and/or the second and fourth materials are identical. Advantageously, the thicknesses of the two protective films are identical or substantially identical and/or the thicknesses of two outer encapsulating films are identical or substantially identical. This makes it possible to obtain a symmetrical panel, which allows optimal mechanical protection of the active elements.

In a preferred embodiment, the active elements are coated within the inner encapsulant film.

In one embodiment, the panel comprises at least two active elements adapted to emit light, in particular at least two active elements adapted to emit light connected to each other. The number of active elements in the panel may in particular be equal to two, three, four, five, six, seven, eight, nine or ten or be included in any interval delimited by two of these values.

The active elements present in the panel are active elements adapted to emit light. The terms "active elements", "luminous active elements" and "active elements adapted to emit light" are used indifferently in the present application to designate these elements. These may in particular be light-emitting diodes (LEDs) mounted on a semi-rigid or flexible conductive electronic circuit support such as a printed circuit (PCB). Alternatively, they may be other elements adapted to emit light, for example OLEDs (organic light-emitting diodes), preferably on a support, individual LEDs, preferably on a support, or LED strips. Preferably, an active element adapted to emit light comprises at least one luminous element on a support allowing it to be powered. Advantageously, the thickness of the active elements is less than 10 mm, better still less than 7 mm, ideally less than 4 mm.

Advantageously, the active element comprises at least two light elements connected in parallel. This allows in particular durability in the event of failure since, unlike the case where the light elements are connected in series, the failure, for example the electrical failure, of one light element does not affect the operation of the other light elements connected to it.

The active elements may have a preferred lighting direction. The active elements may, for example, produce tangential lighting, i.e. in a main direction forming an angle of less than 90° with the surface of the roadway (or the first protective film), in particular lighting directed towards a motorist. The lighting may, on the contrary, be directed upwards (main lighting direction normal to the surface of the roadway) to be visible to pedestrians. The same slab may comprise active elements all having the same lighting direction. Alternatively, the same slab may comprise at least two active elements with different lighting directions. The lighting direction of the active elements in the slab may depend in particular on their position in the slab or in the pattern formed by the slab. Optical elements such as diffusers, reflectors, prisms and/or lenses may be integrated into the luminous slab between the first protective film and the active elements to optimize light perception.

The color of the light emitted by the active elements may be any color suitable for the purpose. In one embodiment, the active element emits white light. In another embodiment, the active element emits colored light, for example, colored light selected from the group consisting of yellow light, blue light, red light, and green light. In one embodiment, the active element emits light of the same color as the marking in which it is integrated, and/or of the same color as the color of the panel. In one embodiment, all the active elements of the panel emit the same color. In another embodiment, the active elements of the same panel emit different colors.

The nature, color, shape and/or relative position of the different active elements in the slab are modular and can be adapted according to a pattern that one wishes to form when all or part of the active elements emit light.

In one embodiment, at least one active element of the panel comprises a printed circuit board (PCB) on which at least one light-emitting diode (LED) is mounted. When the active elements are LEDs mounted on a PCB support, the PCB support can be of any shape. This method makes it possible to assemble the LEDs in a customized manner, in particular in terms of alignment of the LEDs, spacing between LEDs, and/or orientation of the LEDs. The PCB support is preferably in the form of a comb comprising a base and at least two substantially parallel fingers. Such a comb shape makes it possible in particular to minimize material losses during the manufacture of the PCB support. Indeed, the PCB support can be manufactured by forming two interdigitated combs on the same plate, which minimizes material losses. In addition, the combs advantageously comprise pads (plus and minus terminals) at the ends of each finger, or even at each LED, in order to allow on the one hand a cutting of the assembly (PCB + LEDs) according to the desired shape and size, up to the level of the unitary element comprising a single LED on its PCB support, and on the other hand the connection of the active elements between them according to the desired shape and size, in particular to form a pattern. Advantageously, the fingers of the comb are breakable between each LED, which allows custom layout. For example, it may be a printed circuit support whose machining shape allows simple cutting, such as a printed circuit in the form of a comb, comprising a base and at least two substantially parallel fingers on which are positioned luminous elements, in particular LEDs. Advantageously, each finger of the comb comprises an alignment of at least two elements luminous element along the length of the finger and a single luminous element along the width of the finger before cutting. The junction between two such active elements can be made simply by connecting the positive or negative terminals of the active element supports by any suitable connection, for example with 5 mm wide tin-coated copper tape.

The films forming the stack of layers of the slab according to the invention are, independently of one another, advantageously continuous, in particular the first protective film and/or the second protective film.

The pattern obtained may be a simple pattern, such as a line, a square or a rectangle, in particular for illuminating an area corresponding to a road marking, but it may also be a more complex pattern. For example, geometric shapes, signs, patterns, directional or turn-off arrows, zebras, predefined or dynamic messages may be displayed. The pattern may be obtained either with a single panel according to the invention, or by means of an assembly of several illuminated panels according to the invention. In one embodiment, the pattern is obtained with a number of panels between 1 and 15 panels, preferably between 1 and 10 panels, in particular between 2 and 3 panels. The dimensions of the pattern are either defined in the standards in force, or defined according to the use case. A deformation such as anamorphosis may be applied to the pattern so that the pattern is visible to users, regardless of their position and/or speed.

The slab according to the invention can be of any shape. Preferably, the slab according to the invention has a rectangular shape. Preferably, the width of the slab is greater than or equal to 10 cm. Preferably, the length of the slab is less than or equal to 2 m.

One of the advantages of the invention is the colorimetric adaptation of the tile to the existing one. Indeed, the tile used as a road marking element must appear, when the active elements are switched on, in the desired color. It must also, in certain configurations, present a rendering, when the active elements are switched off, in accordance with road marking standards (according to, for example, NF EN 1436). Thus, in the event of a failure of the system or its power supply, the road user will perceive a compliant road marking. In other configurations, when the active elements are switched off, the rendering must on the contrary , be the color of the road surface, so that the user cannot distinguish the slab from the surrounding road surface.

Thus, advantageously, at least one of the first protective film, the second protective film and the at least one active element or a part thereof is colored. In the case where the active element is colored, if it is a PCB support on which LEDs are mounted, the PCB support may preferably be colored. The coloring may for example be black, i.e. bitumen color, or white, green, blue or yellow, i.e. the color of a road marking, so that the tile fits perfectly into the marking when the active elements do not emit light. In the case of use on a trafficable roadway not constrained by the regulations in force in France, the range of usable colors is wider and may include any desired shade of color and/or texture.

In one embodiment, a suitable formulation with a judicious choice of proportion of transparent resin and paint or pigments is used as the first material. For example, the transparent resin of the first material may comprise a proportion of pigments of between 0 and 50%, better between 0.2 and 10%, and ideally between 0.3 and 5% by mass relative to the total mass of the resin + pigments assembly.

In a second embodiment, a suitable formulation with a judicious choice of proportion of resin and paint or pigments is used as a fifth material, and/or at least part of the active elements (support) is judiciously colored. In this case, the first material may be as described in the preceding paragraph, or a transparent material.

In a third embodiment, a color can be obtained by adding a decorative sheet under the active elements.

The coloring of the different parts of the luminous panel can in particular be obtained by incorporating paint and/or pigments of the appropriate color, for example TiO ₂ pigments for a white color, into one of the components of said parts, for example in the matrix of said parts.

The assembly of the light elements such as LEDs on the support, PCB or ribbon in particular, is chosen to optimize the electrical architecture, for example to allow voltage to be increased, in particular up to 12 volts, up to 24 volts or even up to 60 volts, while respecting the electrical standards in force, in particular the TBTS (Very Low Safety Voltage) standard. The spacing between LEDs is chosen according to the intended uses. Thus, it can be chosen so that a motorist perceives a homogeneous line and not a matrix display. For this purpose, in the direction of travel, the distance between LEDs can be less than 30 cm, better less than 15 cm, ideally between 1 cm and 10 cm. Alternatively, if LED strips are used, the strips are oriented in the direction of travel of the vehicles, which can be advantageous in particular in the case of road markings comprising two parallel lines. The slab according to the invention is thin, which allows its easy incorporation into an existing roadway. For example, the slab has a thickness between 1 mm and 10 mm, preferably between 3 mm and 5 mm.

• un premier film de protection, disposé en face avant de la dalle lumineuse, en un premier matériau,
• un premier film encapsulant extérieur, en un deuxième matériau,
• un film encapsulant intérieur, en un troisième matériau,
• un deuxième film encapsulant extérieur, en un quatrième matériau,
• un deuxième film de protection, disposé en face arrière de la dalle lumineuse, en un cinquième matériau,

• l'un des films choisis parmi le premier film encapsulant extérieur, le film encapsulant intérieur et le deuxième film encapsulant extérieur enrobant au moins un élément actif adapté pour émettre de la lumière,
• chaque élément actif adapté pour émettre de la lumière comprenant au moins un élément lumineux sur un support permettant de l'alimenter,
• le procédé comprenant les étapes suivantes :
  1. (a) la fourniture d'au moins un élément actif adapté pour émettre de la lumière comprenant au moins un élément lumineux sur un support permettant de l'alimenter,
  2. (b) le positionnement du au moins un élément actif adapté pour émettre de la lumière sur un empilement comprenant le deuxième film de protection et le second film encapsulant extérieur,
  3. (c) la lamination du film d'encapsulant intérieur sur le au moins un élément actif de sorte à combler au moins en partie les espaces entre les éléments actifs par le matériau du film d'encapsulant intérieur, et à recouvrir au moins partiellement le au moins un élément actif avec le matériau du film d'encapsulant intérieur, et
  4. (d) la lamination sur le film d'encapsulant intérieur d'un empilement comprenant le premier film d'encapsulant extérieur et le premier film de protection.

A second object of the invention is a method of manufacturing a luminous panel, successively comprising:

• a first protective film, placed on the front of the light panel, made of a first material,
• a first outer encapsulating film, made of a second material,
• an inner encapsulating film, made of a third material,
• a second outer encapsulating film, made of a fourth material,
• a second protective film, placed on the back of the light panel, in a fifth material,

• one of the films selected from the first outer encapsulating film, the inner encapsulating film and the second outer encapsulating film coating at least one active element adapted to emit light,
• each active element adapted to emit light comprising at least one luminous element on a support allowing it to be powered,
• the method comprising the following steps:
  1. (a) providing at least one active element adapted to emit light comprising at least one luminous element on a support enabling it to be powered,
  2. (b) positioning the at least one active element adapted to emit light on a stack comprising the second protective film and the second outer encapsulating film,
  3. (c) laminating the inner encapsulant film onto the at least one active element so as to at least partially fill the spaces between the active elements with the inner encapsulant film material, and to at least partially cover the at least one active element with the inner encapsulant film material, and
  4. (d) laminating to the inner encapsulant film a stack comprising the first outer encapsulant film and the first protective film.

In one embodiment, the manufacturing method is a method for manufacturing a slab according to the invention. All the characteristics and embodiments detailed above for the slab are of course applicable to the manufacturing method according to the invention.

Advantageously, the at least one active element provided in step (a) is obtained by cutting according to a desired pattern of a breakable support on which at least one luminous element is mounted. The cutting makes it possible to obtain active elements of any size and/or any shape. The cutting can be carried out by any suitable technique known to those skilled in the art, and can be done along straight lines as well as curved lines.

Advantageously, step (b) of the manufacturing method according to the invention comprises the attachment of at least one active element to the second protective film through the second outer encapsulant film. This attachment allows for better positioning of the active elements in the slab, which is important for the desired final pattern to be obtained. Alternatively, the active elements may be attached to the second outer encapsulant film. The attachment may comprise the addition of a fixing layer such as a layer of adhesive between the active elements and the second outer encapsulant film, or by preforming the surface of the second encapsulant film before positioning the active elements. In a third embodiment, maintaining the positioning of the active elements in the slab is achieved by positioning spacers between the active elements, in particular between the fingers of the PCB "comb", and/or by connecting said two active elements. two, preferably at the “plus” and “minus” poles of the power supply.

Advantageously, for the manufacture of a light panel, an active element is used comprising at least one light element mounted on a support allowing it to be powered, said support being obtained by cutting according to a desired pattern of a breakable support. Advantageously, the breakable support is a breakable printed circuit support. For example, it may be a printed circuit support whose machining shape allows simple cutting, such as a printed circuit in the form of a comb, comprising a base and at least two substantially parallel fingers on which light elements, in particular LEDs, are positioned. Advantageously, each finger of the comb comprises an alignment of at least two light elements in the direction of the length of the finger and a single light element in the direction of the width of the finger.

A third subject of the invention is a functionalized trafficable roadway, comprising a trafficable roadway on which at least one luminous slab according to the invention is fixed by means of a fixing layer, the first protective film of the luminous slab being optionally covered by a coating layer to allow the passage of pedestrians and/or vehicles, the coating layer allowing all or part of the light emitted by the luminous slab to pass through and having a textured outer surface. In the case where the first protective film of the luminous slab is not covered by a coating layer, said first protective film preferably comprises texturizing agents providing a certain adhesion.

The coating layer provides the desired grip properties for the functionalized road surface. For example, it can provide good tire/road grip properties, such as those defined by the NF EN 1436 standard in particular. The coating layer can also provide the desired optical properties, such as luminance and/or retroreflection properties.

These optical properties can in particular be obtained by a coating layer comprising a mixture of grains and/or beads of glass and/or corundum, in a dosage ranging from 10 to 1000 g/m ² , better 50 to 500 g/m ² , ideally 60 to 400 g/m ² . The granulometry of these elements is substantially between 0 mm and 3 mm, better between 0.1 mm and 1.5 mm, ideally between 0.2 mm and 1 mm. In addition, the coating layer may comprise elements improving retroreflection, for example balls of a transparent material, the optical index of which is between 1 and 2.5, better between 1.1 and 2, ideally between 1.2 and 1.9. The dosage of these elements may range from 10 to 1000 g/m ² , better 50 to 500 g/m ² , ideally 60 to 400 g/m ² . The particle size of these elements is between 0 mm and 3 mm, better between 0.1 mm and 1.5 mm, ideally between 0.2 mm and 1 mm.

Advantageously, the slab is fixed to the trafficable roadway by at least one fixing layer, in particular a layer of adhesive. The adhesive may be colored, in order to contribute to the colorimetric integration of the slab with the existing structure as described above. The shades of colors that can be used and the coloring techniques are as described above for the other parts of the slab that can be colored.

1. (a') fourniture d'une dalle lumineuse telle selon l'invention ou d'une dalle lumineuse obtenue par un procédé de fabrication selon l'invention,
2. (b') fixation de la dalle lumineuse sur une chaussée circulable, par l'intermédiaire d'une couche de fixation,
3. (c') dépôt d'une couche de revêtement, sur le premier film de protection de la dalle lumineuse, pour permettre le passage de piétons et/ou de véhicules, la couche de revêtement laissant passer tout ou partie de la lumière émise par la dalle lumineuse et présentant une surface extérieure texturée.

Advantageously, a method for manufacturing a functionalized trafficable roadway comprises the following steps:

1. (a') provision of a luminous panel as according to the invention or of a luminous panel obtained by a manufacturing method according to the invention,
2. (b') fixing the luminous slab on a trafficable road surface, by means of a fixing layer,
3. (c') depositing a coating layer, on the first protective film of the luminous panel, to allow the passage of pedestrians and/or vehicles, the coating layer allowing all or part of the light emitted by the luminous panel to pass through and having a textured exterior surface.

In the present invention, the term "substantially" relating to a value means an interval of plus or minus 10% around said value, preferably plus or minus 5%, in particular plus or minus 1%.

In the present invention, any interval is understood to be exclusive of limits. Unless otherwise specified, the term "higher" means "strictly higher", and the term "lower" means "strictly lower".

In the present invention, the term "include" and its variations are understood to be non-limiting, that is to say, they do not exclude the present invention from other components or other steps. In particular embodiments, this term may be interpreted as “consisting essentially of” or “consisting of”.

Of course, various other modifications may be made to the invention within the scope of the appended claims. The various features, variations and embodiments of the invention may be combined with each other in various combinations to the extent that they are not incompatible or mutually exclusive.

Brief description of the drawings

• La figure 1 est une représentation générale d'une dalle lumineuse selon l'invention,
• La figure 2 est un schéma d'une dalle lumineuse selon l'invention,
• La figure 3 est un schéma d'une dalle lumineuse selon l'invention intégrée sur une chaussée existante,
• La figure 4 est un schéma de différents modes d'éclairage qui peuvent être obtenus avec des dalles selon l'invention,
• La figure 5 est une dalle lumineuse selon l'invention non colorée intégrée dans une chaussée,
• La figure 6 est une dalle lumineuse selon l'invention colorée en blanc et intégrée dans une chaussée,
• La figure 7 est un élément actif lumineux comprenant des LEDs et résistances organisées en parallèle sur un support PCB en forme de peigne,
• La figure 8 est un schéma global montrant différents modes de connexion des PCBs entre eux,
• La figure 9 est un schéma des connexions de la zone désignée par « Zoom 1 » sur la figure 7,
• La figure 10 est un schéma des connexions de la zone désignée par « Zoom 2 » sur la figure 7,
• La figure 11 est un schéma des connexions de la zone désignée par « Zoom 3 » sur la figure 7.

In addition, various other characteristics of the invention emerge from the appended description given with reference to the drawings which illustrate non-limiting forms of embodiment of the invention and where:

• There Figure 1 is a general representation of a light panel according to the invention,
• There Figure 2 is a diagram of a light panel according to the invention,
• There Figure 3 is a diagram of a light slab according to the invention integrated into an existing roadway,
• There Figure 4 is a diagram of different lighting modes that can be obtained with panels according to the invention,
• There Figure 5 is a luminous slab according to the invention, not colored, integrated into a roadway,
• There Figure 6 is a luminous slab according to the invention colored in white and integrated into a roadway,
• There Figure 7 is an active luminous element comprising LEDs and resistors organized in parallel on a comb-shaped PCB support,
• There figure 8 is an overall diagram showing different ways of connecting PCBs together,
• There Figure 9 is a diagram of the connections of the area designated by “Zoom 1” on the Figure 7 ,
• There Figure 10 is a diagram of the connections of the area designated by “Zoom 2” on the Figure 7 ,
• There Figure 11 is a diagram of the connections of the area designated by “Zoom 3” on the Figure 7 .

It should be noted that in these figures the structural and/or functional elements common to the different variants may have the same references.

Description of the embodiments

The 100 light panel shown on the Figure 1 is a general representation of a slab according to the invention. It comprises the stack of a first protective film 101, a first outer encapsulating film 102, an inner encapsulating film 103 which coats at least one active element 104, a second outer encapsulating film 105, and finally a second protective film 106.

The 100 light panel shown on the Figure 2 comprises the stacking of a first protective film 101 made of a pre-impregnated material (pre preg) which is a composite of fibers and resin, such as a composite of epoxy resin and glass fibers, a first outer encapsulating film 102 which serves as a moisture barrier to protect the active elements, an inner encapsulating film 103 made of a so-called soft encapsulating material, which coats at least one active element 104 comprising a printed circuit board (PCB) support and an LED, a second outer encapsulating film 105 which serves as a moisture barrier, and finally a second protective film 106 made of a pre-impregnated material (pre preg) which is a composite of fibers and resin, such as a composite of epoxy resin and glass fibers.

There Figure 3 represents the integration of a luminous slab 100 into an existing roadway. The luminous slab 100 is fixed to the roadway 110 by means of a layer of bonding resin 109. The luminous slab 100 is covered with a wearing course 107 allowing all or part of the light emitted by the luminous slab 100 to pass through and having a textured outer surface. The wearing course 107 makes it possible in particular to provide the grip necessary for traffic on the functionalized roadway. Between the luminous slab 100 and the wearing course 107 there is an interfacial layer 108 making it possible to maximize compatibility between the wearing course 107 and the first protective film 101. The interfacial layer 108 makes it possible to promote (primary) adhesion. In the embodiment of the Figure 3 , the 100 light panel includes in particular a first protective film 101 (front face), active luminous elements 104 and a second protective film 106 (rear face).

There Figure 4 represents three different lighting modes that can be obtained with a light panel according to the invention. Thus, with suitable control, the light elements 104 of the light panel can emit so-called normal lighting, that is to say with a main direction of the light rays normal to the surface of the roadway 110, and a homogeneous distribution on either side of it (section A of the Figure 4 ). Alternatively, the light elements may emit so-called tangential lighting, i.e. with a main direction of the light rays which forms an angle of less than 90°, in particular less than 45°, with the surface of the roadway 110 (section B of the Figure 4 ). So-called mixed lighting can also be obtained by combining light elements 104 emitting normal lighting and light elements 104 emitting tangential lighting (section C of the Figure 4 ). Of course, depending on the control, the lighting direction of each light element can be adapted to any desired direction.

There Figure 5 and the Figure 6 present embodiments in which the light panel 100 is either transparent ( Figure 5 ), either colored, for example white ( Figure 6 ). The light panel 100 comprises a first protective film (front face) 101, active LED light elements 104 and a second protective film (back face) 106. The second protective film 106 can be either translucent, as in the embodiment of the Figure 5 , either colored, in particular white as in the embodiment of the Figure 6 The luminous slab 100 is covered with a translucent textured wearing course 107, and fixed to the roadway 110 by means of an adhesive 109. The color can alternatively be given to the slab by coloring other elements of the luminous slab integrated into the roadway, for example coloring the PCB circuit of the active elements 104, or coloring the adhesive 109.

There Figure 7 shows the electrical diagram of an active element 104 comprising, on a PCB support, LEDs connected in parallel to each other. The PCB has a comb shape that is optimal both in terms of optimization of the materials used during its manufacture, and in terms of versatility of accessible shapes and possible junctions. The luminous active element of the Figure 7 includes a comb whose fingers are all the same length. However, each of the fingers of the comb can be, in the spirit of the invention, more or less shortened by simple cutting to obtain a desired pattern illuminated by the active element. The cutting can be carried up to the level of the unit LED on its support if necessary. Connecting the LEDs in parallel allows their independence. Each LED is coupled to a resistor.

There figure 8 is a diagram exemplifying the simplified connection of several active luminous elements comprising PCB supports according to the invention between them, the connections being able to be made equally well between two comb-shaped PCB bases, between the base of a comb-shaped PCB and the end of the fingers of another PCB (zoom 1, also represented in Figure 9 ), between the finger tips of two PCBs (zoom 2, also shown in Figure 10 ), or between the bases of two comb-shaped PCBs, notably perpendicular to each other (zoom 3, also shown in Figure 11 ). Connections between PCBs can be made using tin-coated copper tape, especially 5 mm wide tin-coated copper tape.

Claims (15)

1. A light slab (100) able to be integrated into a trafficable pavement, comprising in succession:

   - a first protective film (101), arranged on the front face of the light slab, made of a first material,

   - a first external encapsulating film (102), made of a second material,

   - an internal encapsulating film (103), made of a third material,

   - a second external encapsulating film (105), made of a fourth material,

   - a second protective film (106), arranged on the rear face of the light slab, made of a fifth material,

   one of the films, chosen among the first external encapsulating film (102), the internal encapsulating film (103) and the second external encapsulating film (105), coating at least one active element adapted to emit light (104),

   each active element adapted to emit light (104) comprising at least one light element on a support allowing it to be powered,

   the first material, the second material, the third material, the fourth material and the fifth material having Young's moduli E₁, E₂, E₃, E₄ and E₅, respectively, and coefficients of thermal expansion CTE₁, CTE₂, CTE₃, CTE₄ and CTE₅, respectively,

   E₁ and E₅ being equal or not different by more than 30%, E₂ and E₄ being equal or not different by more than 30%, $${\mathrm{E}}_1>{\mathrm{E}}_2\mathrm{and}{\mathrm{E}}_4<{\mathrm{E}}_5,$$

   

   CTE₁ and CTE₅ being equal or not different by more than 30%, CTE₂ and CTE₄ being equal or not different by more than 30%, $${\mathrm{CTE}}_1<{\mathrm{CTE}}_2\mathrm{and}{\mathrm{CTE}}_4>{\mathrm{CTE}}_5.$$

   
2. The light slab (100) according to claim 1, wherein an active element adapted to emit light (104) comprises at least two light elements connected in parallel.
3. The light slab (100) according to claim 1 or 2, wherein at least one among the first protective film (101), the second protective film (106) and the at least one active element (104) or a part of the latter is coloured.
4. The light slab (100) according to any one of claims 1 to 3, wherein at least one active element (104) comprises a printed circuit on which at least one light-emitting diode is mounted.
5. The light slab (100) according to claim 4, wherein the printed circuit is in the form of a comb comprising a base and at least two substantially parallel fingers.
6. The light slab (100) according to any one of claims 1 to 5, wherein the first material and/or the fifth material is a composite comprising glass fibres and an epoxy resin.
7. The light slab (100) according to any one of claims 1 to 6, wherein the second material and/or the fourth material is a ionomer.
8. The light slab (100) according to any one of claims 1 to 7, wherein the third material is a thermoplastic polyolefin or a (meth)acrylic resin.
9. The light slab (100) according to any one of claims 1 to 8, wherein the thickness of the first protective film (101) and/or the second protective film (106) is comprised between 0.1 mm and 5.0 mm.
10. The light slab (100) according to any one of claims 1 to 9, wherein the thickness of the first external encapsulating film (102) and/or the second external encapsulating film (105) is comprised between 0.25 and 2.0 mm.
11. The light slab (100) according to any one of claims 1 to 10, wherein the thickness of the internal encapsulating film (103) is comprised between 0.4 and 2.0 mm.
12. A method for manufacturing a light slab (100) comprising successively:

    - a first protective film (101), arranged on the front face of the light slab, made of a first material,

    - a first external encapsulating film (102), made of a second material,

    - an internal encapsulating film (103), made of a third material,

    - a second external encapsulating film (105), made of a fourth material,

    - a second protective film (106), arranged on the rear face of the light slab, made of a fifth material,

    one of the films, chosen among the first external encapsulating film (102), the internal encapsulating film (103) and the second external encapsulating film (105), coating at least one active element adapted to emit light (104),

    each active element adapted to emit light (104) comprising at least one light element on a support allowing it to be powered,

    the method comprising the following steps:

    (a) providing at least one active element adapted to emit light (104) comprising at least one light element on a support allowing it to be powered,

    (b) positioning the at least one active element adapted to emit light (104) on a stack comprising the second protective film (106) and the second external encapsulating film (105),

    (c) laminating the internal encapsulating film (103) on the at least one active element (104) in such a way as to fill at least in part the spaces between the active elements with the material of the internal encapsulating film (103), and to cover at least partially the at least one active element (104) with the material of the internal encapsulating film (103), and

    (d) laminating on the internal encapsulating film (103) a stack comprising the first external encapsulating film (102) and the first protective film (101).
13. The method for manufacturing a slab according to claim 12, wherein the at least one active element (104) provided at step (a) is obtained by cutting according to a desired pattern a cuttable support on which at least one light element is mounted.
14. The method for manufacturing a slab according to claim 12 or 13, wherein step (b) comprises the fastening of at least one active element (104) to the second protective film (106) through the second external encapsulating film (105).
15. A functionalized trafficable pavement, comprising a trafficable pavement on which is fastened at least one light slab (100) according to any one of claims 1 to 11, using a fastening layer (109), the first protective film (101) of the light slab being covered with a coating layer (107), to allow the passage of pedestrians and/or vehicles, the coating layer (107) letting through all or part of the light emitted by the light slab (100) and having a textured external surface.

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