Decorative concrete tile, decorative paving, and method for producing such a tile

Abstract

The invention relates to a decorative concrete tile, such as a decorative concrete floor tile, in particular to compose a decorative paving. The invention further relates to a decorative paving comprising a plurality of adjacent decorative concrete tiles according to the invention. The invention also relates to a method for production of a decorative concrete tile, in particular a decorative concrete tile according to the invention.

Description

[0001] The invention relates to a decorative concrete tile, such as a decorative concrete floor tile, in particular a paver, a decorative wall tile, or a decorative roof tile. The invention further relates to a decorative paving comprising a plurality of adjacent decorative concrete tiles according to the invention. The invention also relates to a method for production of a decorative concrete tile, in particular a decorative concrete tile according to the invention.

[0002] Concrete paving blocks or tiles are one of the most widely used construction materials in the world. Because they are easy to install, strong, durable, inexpensive, weather resistant, and fireproof, they are well suited for building roads, pavements, gardens, and car parks. In addition to resisting weather fluctuations, it is important these concrete tiles meet other requirements, such as the fact that the upper surface should have a rough texture to act as anti-slip surface, both in dry and wet conditions, as the concrete tiles are often applied in areas where people walk and as slippery tile surfaces increase the risk that people will slip, fall, and injure themselves. At the other hand, there is also an increasing need to aesthetically more attractive tiles. Although it is known to realize to provide concrete tiles with a coloured granular top section, the aesthetic design variations are still relatively limited. US 2019 / 0337853 A1 for example relates to fiber cement flooring products. JP H02 256703 A for example relates to improvements in surface finishing methods for concrete-based imitation stone products.

[0003] It is an object to the invention to provide an improve concrete tile having anti-slip properties and an improved aesthetical character.

[0004] This object can be achieved by providing a decorative concrete tile according to the appended claims.

[0005] By providing the concrete tile body with a decorative print layer, the concrete tile as such can be provided with an infinite number of designs. It has been found that by merely printing the decorative layer on the concrete tile and by covering said decorative layer with one or more cover layers in particular to protect said decorative layer, the upper surface of the concrete tile will become too slippery (too flat) to apply the tile in wet conditions as people, walking (or cycling) on these tiles, may easily slip, fall, and injure themselves. In order to solve this problem and to improve the anti-slip properties of the tile as such, it was found that actively roughening the tile body during the production process, prior to applying the decorative layer, leads to a sufficiently rough upper surface of the tile as such to meet the desired anti-slip properties. In this manner, it is not needed e.g. to incorporate anti-slip particles into the top structure, which particles are typically opaque and could therefore affect the aesthetic appearance of the decorative layer. Moreover, these particles typically result in a pattern of sharp spikes, which is often undesired for specific applications, for example in gardens where people may walk on their bare feet on these tiles. Hence, the desired roughened texture of the upper surface of the concrete tile is substantially determined by active roughening the upper surface of the concrete tile body, and originates from underneath the decorative layer. In this manner the aesthetical appearance of the decorative layer will not be affected and will remain intact.

[0006] The decorative concrete tile according to the invention can be used in various indoor or outdoor spaces, such as, for example, gardens, patios, patio decks, pool decks, roofs, roof decks, driveways, walkways, sidewalks, parking lanes, cross walks, intersections, and walls.

[0007] As mentioned above an important aspect of the invention is that the actively roughened texture of the upper side of the concrete tile body is at least partially present and haptically feelable in the upper surface of the tile as such. The active roughening of the upper side of the concrete tile body is a resurfacing step that uses a(n externally applied) substance, such as water, sand, pellets, and / or beads, to (actively) deform (reshape) the initial upper surface of the concrete tile body, typically by means of removal and / or displacement of material (initially) present at the upper surface of the concrete tile body, which will lead to a relatively rough (and hence roughened) upper surface compared to the roughness of the initial upper surface, which provides the upper surface of the concrete tile body an actively roughened texture. Preferably, the roughened texture is a fine texture, in particular a texture on grain level, individual grains may be exposed. Also, the resulting texture may be a random texture, i.e., non-repetitive. Preferably, the at least one decorative print layer is applied on top of the actively roughened texture of the concrete tile body. That is, the at least one decorative print layer is applied on a non-flat surface. Hence, the print layer as such follows this actively roughened texture at least partially, and hence also exhibits at its upper surface a typically tactile, textured upper surface. The adverb "actively" is used that the roughened texture is a texture which is actively realized in / at the upper surface of the concrete tile body during the production process, and not merely an ordinary inherent feature of each conventional concrete tile body. During production the concrete tile body is subject to a treatment which provides the upper surface of the tile body with a more pronounced roughened texture compared to a standard initial texture of a concrete tile body. Preferably, the upper surface of the concrete tile body is a washed upper surface. This means that during production of the tile body the upper surface of the tile body is exposed to water, in particular water spray, to wash out (remove) a fraction of smaller, typically cementitious, particles. This will lead to a more pronounced relief structure (grainy structure) at the upper surface of the tile body, wherein typically larger grains, such as sand grains, will be exposed intensively and will form the upper surface of the tile body. This washing action typically takes place when the tile body is still in wet condition, preferably directly after forming, in particular moulding, of the tile body, and prior to drying (hardening) of the tile body. Washing the upper surface of the (wet) tile body is preferably realized by using one or more water spray nozzles located above of the tile body, wherein water is spray, optionally with some pressure (up to 4 bar), onto the upper surface of the tile body. The temperature of the process water used can be ambient temperature. During this washing action a fraction of the loosened material of the upper surface of the tile body will be flushed away, and often another fraction of loosened material will initially remain on said upper surface of the tile body. Preferably, this residual fraction of loosened material is removed prior to printing the decorative layer. To this end, it is advantageous to firstly allowing the washed, wet tile body to harden for a certain amount of time, such as 12-36 hours at ambient or elevated temperature, before removing the residual fraction of loosened material from the upper surface of the tile body. Removal of this residual fraction of loosened material from the upper surface of the tile body is typically realized by means of a vacuum device (suctioning device). However, it may be preferred to brush the upper surface of the hardened tile body prior to removal of loosened material from the upper surface of the tile body to remove sharp, spikey particles (e.g. sand grains) from the upper surface, which will typically improve the comfort and user-friendliness of the tile as such. Hence, the upper surface of the concrete tile body is preferably a brushed upper surface, more preferably a washed and brushed upper surface. The decorative concrete tile according to the invention may be a decorative concrete floor tile, such as a concrete paving block, as for example defined in standard EN 1338:2003, and / or a concrete paving flag, as for example defined in standard EN 1339:2003.

[0008] It is also, optionally additionally to the washing action described above, imaginable, that the upper surface of the concrete tile body is provided with an actively roughened texture, by subjecting this upper surface to a blasting action, such as a sand blasting action and / or shot blasting action. This blasting action is typically performed after hardening of the initially wet concrete tile body. Hence, that actively roughened upper surface of the concrete tile body may be an (actively) blasted surface. Suitable blasting techniques to actively roughen the texture of the upper surface of the concrete tile body are, for example, shot blasting (bullet blasting), sand blasting, or vacuum blasting. With shot blasting, steel "balls" (bullets) are blown against the surface with a throwing wheel. The abrasive is reused several times through the use of a closed circuit. Dust and dirt are typically sealed off by an air stream and removed by a vacuum cleaner. For sand blasting, use is made of so-called grit grains. These grit grains are blown against a surface using a high-pressure machine. Vacuum blasting uses the same technique as sandblasting or shot blasting. Grit grains of aluminum oxide are blown against a surface using a high-pressure machine. As indicated above, it is preferred that, in order to provide an actively roughened texture to an upper side of the concrete tile body, material is removed from said upper tile body surface. In this respect, material is removed from the upper surface of the concrete tile body by means of a(n externally applied) substance. Said substance may for example be a liquid, in particular water, which may be sprayed onto a preferably still wet upper surface. It is also imaginable that said substance is a shooting substance, such as balls or grains or the like. Preferably and typically substance dependent, the substance may be applied to the upper surface of the concrete tile body under super-atmospheric pressure and / or may be applied under atmospheric pressure.

[0009] Various standards exist to prescribe a minimum slip resistance as well as a method to measure this slip resistance. For example, the standard NEN 7909:2015 gives the requirement and determination method for slip resistance of horizontal or slope flooring in a public or working space. The dynamic friction coefficient is a measure for the slip resistance and gives an indication of the foot trafficking. The flooring may exist of one or more products. The actual slip resistance can be measured any time with the methods of NEN 7909 on location or in a laboratory. During this test a standardized sliding friction testing device (GMG(-200)) is used. During the measurement, the testing device must be pulled at constant speed across the surface to be tested. The required force (that depends on the coefficient of sliding friction of the tile surface) is captured and recorded. Next, the integrated analysis calculates the mean sliding friction value (µ), also referred to as friction coefficient, of the surface across a predefined distance. NEN709:2015 prescribes that this friction coefficient should be at least 0.30 in dry conditions, at least 0.40 in wet conditions, and at least 0.45 in wet conditions in a pool environment. It has been found that the actively roughened texture of the tile body will lead to an upper surface of the concrete tile with a friction coefficient (µ) of at least 0.57, measured according to the aforementioned NEN 7909:2015 standard. This value is considerably higher than the minimum required slip resistance prescribed by this standard, which makes the decorative concrete tile according to the invention well suitable to be applied in each environment. Typically, the friction coefficient (µ), measured according to the NEN7909:2015 standard, of the upper surface of the concrete tile body exceeds the friction coefficient (µ), measured according to the NEN7909:2015 standard, of the upper surface of the concrete tile. The decorative layer and the top structure typically smoothen the actively roughened texture of the concrete tile body to some extent, but as indicated above this smoothening effect still leads to sufficient roughness at the upper surface of the concrete tile as such.

[0010] The concrete tile body is preferably a moulded and densified concrete tile body. This means that at least one wet concrete composition is applied into a mould. This mould can be made of various materials, but is preferably made of metal, in particular stainless steel, as metal is relatively strong and rigid, which allows the concrete tile formed therein to be densified by means of (downward) pressing. Preferably, the concrete tile body comprises a base section and a top section, integrally connected with each other, wherein the composition of the base section is coarser than the composition of the top section. Preferably the mould is initially filled with a material composition of the base section and directly thereafter filled with a material composition of the top section, after which both sections are (com)pressed and densified, typically by means of a pressure plate. The surface of the pressure plate can be flat or can be provided with a relief, dependent on the desired initial relief of the upper surface of the (wet) tile body. Since the tile body is entirely formed in a single mould, wherein the base section and the top section are integrally connected, the tile body can be considered as a monolithic tile body. Preferably, the material composition of the top section comprises less coarse materials than the material composition of the base section. This typically makes the top section softer than the base section and hence more suitable for subjecting an upper surfacer of the top section to a washing treatment, while the base section secures sufficient rigidity of the tile body. Preferably, the base section comprises coarse mineral particles, such as coarse gravel and / or pebbles, with a minimum dimension of at least 2 mm, preferably at least 4 mm, and wherein said top section is substantially free of said coarse mineral particles. Typically, the base section comprises 30-50% by weight of coarse particles having an average diameter of 2-12 mm, preferably 2-8 mm. Typically, the top section is free of such coarse particles and preferably comprises 50-75% by weight of sand, preferably quartz sand, typically having a diameter of 0-2 mm, and preferably 10-30% by weight of slightly larger particles, typically having a diameter of 1-3 mm. The (top section of the) concrete tile body comprises sand grains, preferably quartz sand grains, at least partially defining the upper surface of the concrete tile body.

[0011] The concrete tile body typically has a (somewhat) porous structure which may easily lead to lime bloom. Hence, it is advantageous that the concrete tile body is impregnated with an (meth)acrylate comprising substance, in particular formed by a mixture comprising acrylate and (2-methoxymethylethoxy)-propanol. The acrylate used is preferably a nanometric acrylate. Preferably, this acrylate comprising substance is applied onto a still wet tile body. It is preferred that the acrylate comprising substance further comprises an ether, preferably dipropyleneglycolmethylether. This will typically improve the solubility of the acrylate compound(s) and will facilitate the penetration of the acrylate compound(s) into pores of the tile body, resulting in an intensive adhesive connection with the acrylate compound(s) and the concrete tile body. The area density of the acrylate comprising substance is preferably 60-120 g / m 2< . The acrylate comprising substance may be used to impregnate the concrete tile body either prior to and / or after hardening of said concrete tile body.

[0012] In a preferred embodiment, the concrete tile body comprises a plurality of side edges, wherein at least one side edge, preferably a plurality of side edges, is provided with one or more protruding spacers configured to create an intermediate space, in particular grout line, in between adjacent decorative concrete tiles. More preferably, each edge is provided with at least one spacer. Preferably the spacers make an integral part of the tile body, and are typically also substantially made of a concrete based composition.

[0013] Although it is imaginable that the decorative layer is applied by transfer printing or other traditional printing techniques, it is preferred that the decorative print layer is a digitally printed decorative print layer. Digital printing is a method of printing from at least one digital image directly to a media. In this manner, an infinite number of decorative designs can be printed, in a moreover accurate manner with a high level of detail, which leads to realistic appearances and unique, one-of-a-kind decorative tiles. The printed décor image(s) of the decorative layer(s) may be based on the CMYK colour principle where the white colour is typically provided by the surface of the white base coat (if applied). This is a 4-color setup comprising cyan, magenta, yellow and black. Mixing these together will give a colour space / gamut, which is relatively small. To increase specific colour or the total gamut spot colours may be added. A spot colour may be any colour. One or more additional colours may be applied, such as at least one additional colour selected from the group consisting of: orange, green, blue, red, white, light grey, light magenta, and light cyan. These colours may be used separately or in combinations. The colours are typically mixed and controlled by a combination of software and hardware (print engine / print heads). However, it is often preferred to use inorganic inks to realize the decorative layer. Typically, these inks have more natural colours and can be exposed long-lastingly to various weather conditions without discoloration.

[0014] Preferably, at least one primer layer is situated in between the concrete tile body and the decorative print layer. The application of one or more primer layers will typically improve the adhesion of the decorative layer to the concrete body, which will be in favour of the durability of the tile. The primer layer preferably comprises an isothiazole. It can be advantageous that the tile comprises at least two primer layers applied on top of each other. In this manner thinner primer layers can be applied, which facilitates a (controlled) hardening of said layers. Preferably, the area density of at least one primer layer is situated 30-70 g / m 2< , preferably approximately 30-60 g / m 2< .

[0015] Preferably, the at least one cover layer of the top structure is formed by a protective crosslinked coating, applied, preferably directly, onto the decorative print layer. This crosslinked coating is typically configured to consolidate and preserve the decorative layer, and is therefore preferably applied directly on top of the decorative layer. The crosslinked coating preferably comprises at least one isocyanate and / or at least one alkoxyalcohol. The area density of the crosslinked coating is preferably 50-110 g / m 2< , more preferably approximately 90 g / m 2< .

[0016] Preferably, at least one cover layer of the top structure is formed by at least base coat layer, preferably a plurality of base coat layers. More preferably, the one or more base coat layers are applied directly on top of the crosslinked coating. The base coat layer typically act as wear layer. From a production point of view, it can be advantageous to successively apply a plurality of thinner base coat layers rather than applying one thicker base coat layer. This latter renders a controller hardening more difficult. Preferably, the base coat layer(s) is / are cured by means of ultraviolet (UV) radiation, also referred to as UV hardened layer(s). Preferably, at least one base coat layer comprises a silane, preferably an alkylalkoxysilane and / or a trimethoxysilane based compound. A silane compound typically provides the base coat a hydrophobic character, which is favourable for outdoor application of the tiles. Moreover, a silane compound typically improves the flowability of the base coat layer during application resulting in a base coat layer with a uniform thickness. Preferably, the area density of at least one base coat layer is 30-100 g / m 2< , preferably approximately 40-80 g / m 2< . The overall area density of the one more base coat layers is preferably approximately 50-90 g / m 2< .

[0017] In a preferred embodiment at least one cover layer of the top structure is formed by at least a top coat layer defining the upper surface of the concrete tile, wherein said top coat layer preferably covers said at least one base coat layer. The top coat layer preferably provides an improved scratch resistance to the tile. The top coat layer preferably comprises an acrylate, preferably a diacrylate, and / or a sebacate. The sebacate compound, such as bis(I,2,2,6,6-pentamethyl-4-piperidinyl)sebacate, acts as compatibilizer between the acrylate compound and further layers of the top structure and / or of the tile, which typically improves the adhesive strength of the top coat layer. The top coat layer may also include further constituents, such as an acetate compound. Preferably, the area density of the top coat layer is 5-30 g / m 2< . Preferably, the top coat layer is a UV hardened top coat layer.

[0018] It is imaginable that at least a part of the upper surface of the concrete tile body is provided with actively aged texture. This texture by aging can be realized by damaging the upper surface of the concrete tile body, after hardening and before applying the decorative print layer. This damaging process can e.g. be realized by means of hammering, wherein hammers randomly smash onto the upper surface of the tile body, resulting of breakage of parts of the upper surface, which leads to an aged effect. This aging effect could not only be attractive from an aesthetical point of view, but also leads to additional relief of the upper surface of the tile body, which could be in favour of the slip resistance of the tile as such.

[0019] The top structure is preferably applied by applying one or more cover layers by means of rolling techniques. Preferably, each applied cover layer is hardened (cured) first before applying a possible subsequent cover layer. It is also imaginable that at least a part of the top structure is applied by means of printing, preferably digital printing, more preferably 3D printing. During digital printing of the top structure, a 2D or 3D digital image can be taken as basis and printed accordingly onto the decorative layer. This could result in a printed 3D structure (relief structure or relief pattern) of the top structure, which could contribute to the slip resistance of the tile as such. Preferably, the relief pattern is at least partially aligned in register with at least a part of at least one decor image formed by the printed decorative layer. In this manner artificial grout lines, wood nerves, and various other shapes can be realized in the top structure.

[0020] Preferably, the tile has a thickness situated between 3-8 cm. The shape of the tile can be of various nature and is typically rectangular, optionally oblong rectangular, but also other shapes, like e.g. triangular, pentagonal, and hexagonal shapes can be applied. Preferably, at least a portion of a circumferential upper edge of the tile, in particular the concrete tile body, is chamfered, and preferably the entire circumferential edge is chamfered. This chamfering will reduce the risk of breakage of the tile. Preferably, the chamfered upper edge (portion) of the concrete tile body is substantially covered by the decorative print layer, and preferably also by the top structure.

[0021] Although, as mentioned above, it is not needed to incorporate anti-slip particles into the top structure, it is still imaginable that in an embodiment of the concrete tile according to the invention, the top structure comprises abrasive foreign particles (i.e., particles made from a material different than that of the top structure) to further increase the slip resistance of the tile. In case these abrasive particles would be applied in the top structure the abrasive particles could be formed e.g. by sand, aluminum oxide, carbide particles, and / or another grid material. The initial shape of the abrasive particles formed on the surface of the tile can vary from a pyramid with triangular faces to a conical shape. Optionally, the sidewall edges and / or apex of the abrasive particles can be rounded to reduce the sharpness of the particles.

[0022] The invention also relates to a decorative paving comprising a plurality of a decorative concrete tiles according to the invention.

[0023] The invention further relates to a method for production of a decorative concrete tile, in particular a decorative concrete tile according to the invention, comprising the steps of: A) preparing a wet concrete tile body, preferably by molding and pressing; B) subjecting the upper surface of said concrete tile body to an active roughening treatment, preferably to remove at least a part of material, in particular cementitious material initially present at said upper surface, for example by exposing the upper surface of said wet concrete tile body to water, preferably to water spray, to wash out at least a part of cementitious material initially present at said upper surface, thereby at least partially exposing sand grains present at said upper surface, resulting in an actively roughened texture of said upper surface; C) at least partially hardening said concrete tile body; D) preferably brushing said washed and / or at least partially hardened upper surface; E) preferably removing loosened material from the upper surface, more preferably by means of a vacuum device and / or blowing device; F) preferably, applying at least one primer layer onto the upper side of the hardened concrete tile body; G) printing a decorative layer onto the upper surface of the concrete tile body and / or onto the upper surface of at least one primer layer, and H) applying at least one substantially transparent or translucent top structure on top of said printed decorative layer, wherein said top structure comprises one or more cover layers.

[0024] In case during step B) the upper surface of the wet concrete tile body is exposed to water, preferably to water spray, to wash out at least a part of cementitious material initially present at said upper surface, thereby at least partially exposing sand grains present at said upper surface, step B) is preferably performed prior to step C). In case during step B) the upper surface of the concrete tile body is exposed to another roughening treatment, preferably to a blasting treatment, in particular a sand blasting treatment and / or shot blasting treatment, to blast out and / or displace at least a part of material initially present at said upper surface, thereby preferably at least partially exposing sand grains present at said upper surface, resulting in an actively roughened texture of said upper surface, step B) is preferably performed after step C).

[0025] It is preferred that, in order to provide an actively roughened texture to an upper side of the concrete tile body, material is removed from said upper tile body surface. In this respect, material is removed from the upper surface of the concrete tile body by means of a substance. Said substance may for example be a liquid, in particular water, which may be sprayed onto a preferably still wet upper surface. It is also imaginable that said substance is a shooting substance, such as balls or grains or the like. Said roughening treatment may provide an actively roughened texture to the concrete tile body, in particular by subjecting this upper surface to a blasting action. This blasting action is typically performed after hardening of the initially wet concrete tile body. It is conceivable that said actively roughened texture is provided before applying a primer and / or decorative print layer. Hence, said decorative print layer and / or primer layer may as such be textured. That is, the at least one decorative print layer and / or primer layer are applied on top of the actively roughened texture. Hence, that upper surface of the concrete tile body may be an (actively) blasted surface. Suitable blasting techniques to actively roughen the texture of the upper surface of the concrete tile body are, for example, shot blasting (bullet blasting), sand blasting, or vacuum blasting. With shot blasting, steel "balls" (bullets, beads, or pellets) are blown against the surface with a throwing wheel. The abrasive is reused several times through the use of a closed circuit. Dust and dirt are typically sealed off by an air stream and removed by a vacuum cleaner. For sand blasting, use is made of so-called grit grains. These grit grains are blown against a surface using a high-pressure machine. Vacuum blasting uses the same technique as sandblasting or shot blasting. Grit grains of aluminum oxide are blown against a surface using a high-pressure machine.

[0026] Advantages and further embodiments have been described above already in a comprehensive manner and will be described in further detail in the following part of the description.

[0027] The present invention will hereinafter be further elucidated based on the following non-limitative drawings wherein; figure 1 shows a cross-sectional view of a decorative concrete tile according to the invention; figure 2 shows an enlarged view of a portion of the cross-sectional view depicted in figure 1; figures 3A-3C depict the steps of applying the actively roughened texture to the upper surface of the concrete base tile; and figure 4 shows a flow chart of a non-limitative embodiment of the manufacturing process of the decorative concrete tile.

[0028] Figure 1 shows a non-limitative embodiment of the decorative concrete tile 1 according to the invention. The figure illustrates the concrete tile 1 comprises a base section 3 and a top section 4. The base section 3 and top section 4 are drawn as separate layers, however this is merely indicative, and in reality the sections 3, 4 are preferably integrally connected with each other such that no separate layers can be distinguished and hence form a single concrete tile body. This could be realized by pouring the composition of the base section 3 in a tile mould first, and subsequently pouring the composition of the top section 4 on top of said already poured in base composition. After filling the mould with both compositions they are compressed and densified, for example by means of a pressing plate. The base section 3 preferably comprises particles 6 that are coarser compared to the particles 7 of the top section 4. Base section particles 6 for example have a maximum dimension of between 4-8 mm, and could be of mineral material. Preferably the top section 4 does not comprise said relatively large mineral particles 6. The top section 4 preferably comprises sand, such as quartz sand having a typical diameter of 0-2 mm, additionally particles 7 having a typical size between 1-3 mm are added to the top section 4 composition. After the concrete tile body is formed it is subjected to a washing treatment (see figure 3A), which actively washes away material from the upper surface of the concrete tile. After washing an actively roughened texture is revealed. This texture at least partially defines a textured upper surface 5 of the decorative concrete tile 1. Alternatively and / or in addition to the washing action referred to above, it is also imaginable, that the upper surface of the concrete tile body is provided with a roughened texture 5, by subjecting this upper surface to a blasting action. This blasting action is typically performed after hardening of the initially wet concrete tile body. Hence, that upper surface 5 of the concrete tile body may be an (actively) blasted surface. Suitable blasting techniques to actively roughen the texture of the upper surface of the concrete tile body are, for example, shot blasting (bullet blasting), sand blasting, or vacuum blasting. Figure 2 shows an enlarged view of the circle 2 shown in figure 1. This figure again indicates the concrete tile body is drawn up by a concrete base section 3 and a concrete top section 4 which are integrally formed during moulding. The larger mineral particles 6 provided in the base section 3 contribute to the structural strength of the concrete tile body. This enlarges segment 2 also shows the presence of a cover layer 8. The cover layer 8 is formed by a translucent or transparent material such that the print layer remains visible. The print layer is situated between the cover layer 8 and the concrete base tile which is formed by the concrete base section 3 and concrete top section 4. As schematically shown by this figure, the actively roughened texture of the upper surface of the concrete base tile forms a part of the textured upper surface 5. This can be elaborated as follows, by washing away very fine material from the upper surface the small particles 7 in the top section 4 are exposed. The landscape of exposed particles 7 on the upper surface of the concrete base tile, in particular the top section 4 provide the textured upper surface 5. Since the cover layer 8 is substantially uniform, the actively roughened texture of the concrete base tile is maintained in the upper surface of the decorative tile 1. The textured surface reduces the slip of the decorative tile 1. It is conceivable the cover layer 8 comprises a plurality of layers, such as for example one or more base coat layers, and a top coat layer, which together form the cover layer 8. By applying these layers individually a more uniform cover layer 8 could be realized.

[0029] The process of creating the textured upper surface 5 of the decorative concrete tile 1 will be elaborated in more detailed in figures 3A-3C. Figure 3A shows the decorative concrete tile, in particular the concrete base tile 1 as it is just moulded. In this state the tile 1 is able to maintain its shape during handling. After the tile 1 is moulded, it is treated by means of water sprays 12, these water sprays are provided by nozzles 9 which are positioned above the tile body 1. The nozzles 9 are connected by means of hoses 10 to a water delivering unit 11. The nozzles 9 are preferably directed towards the upper surface of the tile body 1. Each of the sprays 12 covers a certain area of the surface of the tile 1. Preferably, the areas of all sprays 12 together cover the entire upper surface of the tile 1. The water can be sprayed onto the surface of the tile 1 under a pressure of up to 40 bar, such that fine particles, such as cementitious particles are removed from the upper surface of the tile 1, in particular from the top section 4 (not shown). By spraying water onto the tile at least a portion of loosened material will be flushed away, revealing an actively roughened texture 5'. After treating the tile 1 with the water sprays 12, it is cured in a climate room 13. Figure 3B shows the tile 1 having an actively roughened texture 5' is brought into a room 13. To this end the tile 1 is preferably dried in the climate room 13 for 12-36 hours. To allow a controlled hardening process it is preferred to regulate the temperature of the climate room 13, for example by means of a heating element 14.

[0030] Once the tile 1 is fully hardened it could be treated by a subsequent step, depicted in figure 3C. After hardening the tile 1 the upper surface of the tile 1 is treated by a brush 15, preferably a rotating brush 15. By moving the brush over the upper surface of the tile 1, or by moving the tile 1 and keeping the brush 15 stationary, more loosened material is removed and more importantly sharp, spikey objects such as sand grains are treated. These sharp objects could otherwise potentially cause harm or damage objects to the users of the tile. After washing and brushing the tile loosened material might be left on the upper surface of the tile 1, which material could potentially prevent the paint from properly attaching to the tile. Hence, prior to any subsequent steps preferably the entire upper surface is treated by a vacuum device 16. The suctioning device 16 depicted in figure 3C shows that any loosened material is sucked from the upper surface and thereby removed. After sucking away any residual material the final roughened texture 5 is shown. This final roughened texture 5 is more prominent then the preliminary roughened texture 5' due to removal of residual material, and brushing to eliminate sharp and / or spikey objects. The end result of the roughened texture 5 is an increased slip resistance.

[0031] Figure 4 shows a non-limitative example of the manufacturing process of the decorative concrete tile 1 according to the invention. Generally the initial step is to prepare a wet concrete tile body in a first step A, which is preferably done using a mould and moulding and pressing said concrete tile body in a predefined shape. Subsequent to moulding and pressing A the concrete tile body it is washed B, preferably using nozzles to spray water onto the upper surface of the concrete tile body under light pressure such as to wash out at least a part of cementitious material that was present on the upper surface after pressing. Washing B the pressed tile results in an actively roughened texture of said upper surface of the concrete tile body. It is important to execute the washing step prior to the hardening or curing step C, since otherwise the actively roughened texture might not be sufficiently increasing the slip resistance of the tile. However, prior to hardening C it is possible to impregnate B' the tile with an acrylate comprising substance, in order to prevent efflorescence. Optionally, after hardening C the concrete base tile it is possible to actively age C' the concrete base tile. To this end hammers or other objects could be used to treat the hardened upper surface of the concrete tile body to provide it with an aged texture. After hardening C and optionally aging C' the concrete base tile, the tile is brushed D using brushes, which move over the concrete tile base, in particular over the upper surface thereof. However, it is also imaginable that the tile moves and the brushes remain at their position. The brushes allow to grind any sharp spikes or grains and to remove dried cementitious material removed during washing B and / or aging C'. Subsequently it is preferred that the loosened material is sucked or blown away E using a suction and / or blowing device. After the loosened material is fully removed, the tile is hardened, then a primer layer is added F. The process of drying and subsequently adding a primer F could be repeated up to two or three times, such that the entire upper surface is uniformly provided with a primer. It is preferred that the primer is applied by means of a roller onto the upper surface of the concrete base tile. After the final layer of primer is added F, the tile is dried F' in order to cure the primer before printing. After the primer is dried F' the decorative image is printed and dried G on top of the primer layer, preferably the decorative image is printed by using inorganic ink. After the ink is applied and dried G, the cover layer is added H. The cover layer is preferably a multi-layered cover layer. A first layer might be formed by a crosslinking coating H1, which is preferably directly applied onto the decorative print layer G. This crosslinked coating H1 protects the print layer and is configured to consolidate and preserve it. After the crosslinking coating H1 is dried H2, the next layer of the cover layer can be added. Preferably a UV curable base coat layer H3 is added, which typically acts as a wear layer to protect the print layer G. In order to harden the base coat properly, it could be added in a plurality of thinner base coat layers, each of the base coat layers preferably being of the UV curable type. Applying the entire base coat layer H3 in a plurality of successively applied and UV cured steps, is advantageous over applying a single, relatively thick, base coat layer. Once the final base coat layer H3 is UV cured a top coat layer H4 is provided and UV hardened H5. The presently described manufacturing process is merely illustrative, it is conceivable that certain non-crucial steps are omitted in order to speed up the production process. It is furthermore conceivable that certain steps, such as brushing, might be constituted by other means which yield a similar end result.

[0032] It will be apparent that the invention is not limited to the working examples shown and described herein, but that numerous variants are possible within the scope of the attached claims that will be obvious to a person skilled in the art.

[0033] The verb "comprise" and conjugations thereof used in this patent publication are understood to mean not only "comprise", but are also understood to mean the phrases "contain", "substantially consist of", "formed by" and conjugations thereof.

Claims

1. Decorative concrete tile (1), in particular a decorative concrete floor tile, comprising; • a concrete tile body (1) having an upper surface (5) and a lower surface, • at least one decorative top structure affixed, either directly or indirectly, to the upper surface (5) of the concrete tile body (1), comprising: • at least one decorative print layer (G), and • at least one substantially transparent or translucent cover layer (8) covering the print layer (G), characterized in that the upper surface (5) of the concrete tile body (1) is provided with an actively roughened texture (5') such that sand grains of the concrete tile body (1) at least partially define the upper surface (5) of the concrete tile body (1), wherein individual grains are exposed, and wherein said texture (5') at least partially defines a textured upper surface (5) of the decorative concrete tile (1).

2. Decorative concrete tile (1) according to claim 1, wherein the upper surface (5) of the concrete tile body (1) is a washed upper surface (5) and / or wherein the upper surface (5) of the concrete tile body (1) is a brushed upper surface (5), preferably a washed and brushed upper surface (5), and wherein the actively roughened texture (5') is formed by material removal, in particular cement removal, from the initial upper surface (5') of the concrete tile body (1).

3. Decorative concrete tile (1) according to any of the preceding claims, wherein the upper surface (5) of the concrete tile (1) has a friction coefficient (µ) of at least 0.57, measured according to the NEN 7909:2015 standard and / or, wherein the friction coefficient (µ), measured according to the NEN7909:2015 standard, of the upper surface (5) of the concrete tile body (1) exceeds the friction coefficient (µ), measured according to the NEN7909:2015 standard, of the upper surface (5) of the concrete tile (1).

4. Decorative concrete tile (1) according to any of the preceding claims, wherein the concrete tile body (1) is a moulded and densified concrete tile body (1) and / or wherein the concrete tile body (1) comprises a base section (2) and a top section (3), integrally connected with each other, wherein the composition of the base section (2) is coarser than the composition of the top section (3) and / or wherein the base section (2) comprises coarse mineral particles (6) with a minimum dimension of at least 2 mm, preferably at least 4mm and wherein said top section (4) is substantially free of said coarse mineral particles (6), preferably wherein the concrete tile body (1) comprises a plurality of side edges, wherein at least one side edge, preferably a plurality of side edges, is provided with one or more protruding spacers configured to create an intermediate space, in particular grout line, in between adjacent decorative concrete tiles (1), preferably wherein the tile (1) has a thickness situated between 3-8 cm.

5. Decorative concrete tile (1) according to any of the preceding claims, wherein the concrete tile body (1) is impregnated with an acrylate comprising substance, in particular formed by a mixture comprising acrylate and (2-methoxymethylethoxy)-propanol, in particular wherein the acrylate comprising substance further comprises an ether, preferably dipropyleneglycolmethylether, more in particular wherein the area density of the acrylate comprising substance is 60-120 g / m2.

6. Decorative concrete tile (1) according to any of the preceding claims, wherein the decorative print layer (G) is a digitally printed decorative print layer (G), preferably wherein the decorative print layer (G) is at least partially formed by at least one inorganic ink.

7. Decorative concrete tile (1) body according to any of the preceding claims, wherein at least one primer layer is situated in between the concrete tile body (1) and the decorative print layer (G), in particular wherein the primer layer comprises an isothiazole, preferably wherein the tile (1) comprises at least two primer layers applied on top of each other, preferably wherein the area density of said at least one primer layer is situated 30-70 g / m2, preferably 30-60 g / m2.

8. Decorative concrete tile (1) according to any of the preceding claims, wherein at least one cover layer (8) of the top structure is formed by a protective crosslinked coating (H1), applied, preferably directly, onto the decorative print layer (G), and wherein the crosslinked coating (H1) comprises at least one isocyanate and / or at least one alkoxyalcohol, preferably wherein the area density of the crosslinked coating (H1) is 50-110 g / m2.

9. Decorative concrete tile (1) according to any of the preceding claims, wherein at least one cover layer (8) of the top structure is formed by at least base coat layer (H3), preferably a plurality of base coat layers (H3) and / or wherein at least one base coat layer (H3) comprises a silane, preferably a trimethoxysilane based compound, preferably wherein the area density of at least one base coat layer (H3) is 30-100 g / m2, preferably approximately 40-80 g / m2, in particular wherein each base coat layer (H3) is a UV hardened base coat layer (H3).

10. Decorative concrete tile (1) according to any of the preceding claims, wherein at least one cover layer (8) of the top structure is formed by at least top coat layer (H4) defining the upper surface (5) of the concrete tile (1), wherein said top coat layer (H4) preferably covers said at least one base coat layer (H3), preferably wherein the top coat layer (H4) comprises an acrylate, preferably a diacrylate, and / or a sebacate, preferably wherein the area density of the top coat layer (H4) is 5-30 g / m2, in particular wherein each top coat layer (H4) is a UV hardened top coat layer (H4).

11. Decorative concrete tile (1) according to any of the preceding claims, wherein at least a part of the upper surface (5) of the concrete tile body (1) is provided with actively aged texture and / or wherein at least a part of the top structure is applied by means of printing, preferably digital printing, more preferably 3D printing, wherein the texture by aging is realized by damaging the upper surface (5) of the concrete tile body (1), after hardening and before applying the decorative print layer (G).

12. Decorative concrete tile (1) according to any of the preceding claims, wherein the top structure is an embossed top structure defining a relief pattern, preferably wherein the relief pattern is at least partially aligned in register with at least a part of at least one decor image formed by the printed decorative layer (G).

13. Decorative concrete tile (1) according to any of the preceding claims, wherein at least a portion of a circumferential upper edge of the tile (1), in particular the concrete tile body (1), is chamfered, preferably wherein at least a portion of a circumferential upper edge of the concrete tile body (1) is chamfered, and wherein the chamfered upper edge of the concrete tile body (1) is substantially covered by the decorative print layer (G).

14. Decorative concrete tile (1) according to any of the preceding claims, wherein the upper surface (5) of the concrete tile body (1) is a blasted upper surface (5), preferably a shot blasted upper surface (5).

15. Decorative paving comprising a plurality of a decorative concrete tiles (1) according to one of the preceding claims.

16. Method for production of a decorative concrete tile (1), in particular a decorative concrete tile (1) according to any of the claims 1-15, comprising the steps of; A) preparing a wet concrete tile body (1), preferably by molding and pressing; G) printing a decorative layer (G) onto the upper surface (5) of the concrete tile body (1) and / or onto the upper surface (5) of at least one primer layer, and H) applying at least one substantially transparent or translucent top structure on top of said printed decorative layer (G), wherein said top structure comprises one or more cover layers (8); characterized in that, after step A and before steps G and H, the method further comprises the steps of: B) subjecting the upper surface (5) of said concrete tile body (1) to an active roughening treatment, preferably to remove at least a part of material, in particular cementitious material initially present at said upper surface (5), resulting in an actively roughened texture (5') of said upper surface (5); C) at least partially hardening said concrete tile body (1); D) preferably brushing said washed and / or at least partially hardened upper surface (5); E) preferably removing loosened material from the upper surface (5), more preferably by means of a vacuum device (16) and / or blowing device; F) preferably, applying at least one primer layer onto the upper side of the hardened concrete tile body (1); wherein in case step B) is formed by exposing the upper surface (5) of the wet concrete tile body (1) to water, preferably to water spray (12), to wash out at least a part of cementitious material initially present at said upper surface (5), thereby at least partially exposing sand grains present at said upper surface (5), step B) is performed prior to step C); and / or wherein in case step B) is formed by exposing the upper surface (5) of the concrete tile body (1) to a roughening treatment, preferably to a blasting treatment, to blast out and / or displace at least a part of material initially present at said upper surface (5), thereby preferably at least partially exposing sand grains present at said upper surface (5), resulting in an actively roughened texture (5') of said upper surface (5), step B) is performed after step C).

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