Method for implementing a porcelain plate

Abstract

A method for implementing a porcelain plate, comprising the steps of: arranging a decorative layer (L2) having decorations (200) on a first deposition plane (50), gradually depositing the decorative soft layer (L2) from a head (H) to a tail (T); gradually transferring the soft layer (L2) from the first deposition plane (50) to a second deposition plane (83) placed at a lower height than the first deposition plane (50) by deposition, gradually implementing a second layer (L3) on the second deposition plane (83) starting from the tail (T) of the second soft layer (L2).

Description

[0001] The present invention relates to a method for realizing ceramic slabs.

[0002] Over the years, the development of the ceramic production process has led to the realization of tiles initially dedicated exclusively to coatings and floors, which are increasingly larger and have variable thicknesses. The increase in the size of the classic tiles has led to the identification of products realized through new production processes, where the term ceramic slab is precisely due to the realization of larger sizes, which can reach 1800 mm wide to 4800 mm long, with thicknesses up to 30 mm. The term ceramic slab is intended to be equivalent to tile.

[0003] In the production of tiles or slabs, it is often necessary to realize decorations that replicate natural stone or wood. As is known, these materials have a texture that extends throughout the entire mass. This means that, when machined into slabs, the texture extends from the outer surface throughout the thickness, also being visible on the side surfaces of the slab. This texture effect is particularly sought after in the realization of kitchen or bathroom tops, steps, walls or edges, generally in realizations where the side surfaces are also visible for the entire thickness of the slab.

[0004] The application or realization of the decoration is essentially carried out according to a process that comprises the simultaneous laying of a soft layer of decoration already having a thickness realized in soft material, through special decoration devices. The laying of the decoration layer comprises a movement from top to bottom and a horizontal directed relative movement between the decoration or decorated layer and the deposition plane.

[0005] Essentially, the soft layer already having the decoration is laid by the decoration device on the underlying deposition plane. A relative movement is realized between the decoration device and the deposition plane. For example, the decoration source, i.e. the decoration device, is fixed, while the deposition plane is mobile.

[0006] In both cases, the relative movement between the decoration source and the deposition plane produces an inclination of the decoration in the vertical plane parallel to the direction of the relative movement. Essentially, observing the decorated slab on the side surface parallel to the direction of the relative movement, the textures are all inclined in the same way, parallel to each other in an unnatural way, with an angle comprised between approximately 15° and 20°. There is another production process that comprises the realization of the decoration or texture using a pen that can be moved along two horizontal Cartesian axes, structured to deposit the decoration material directly into the thickness of the soft layer already deposited, essentially passing through it. However, this process is characterized by a rather low productivity. In addition, the decoration or texture observed on the side surface parallel to the direction of the relative movement is almost vertical, offering a rather unnatural appearance.

[0007] The aim of the present invention is to provide a method for realizing ceramic slabs that allows the production of slabs without the drawbacks of the currently available ones.

[0008] The main advantage of the method according to the present application is to realize at least one decoration which extends at least partially in the thickness of the body and at least partially on one of the two faces of the ceramic slab and which has an inclination comprised between about 40° and 80° when observed from the side surface of the ceramic slab, thus providing a natural appearance completely similar to natural stone or wood.

[0009] Moreover, the inclination imparted to the decoration gives it considerable stability with respect to the displacement steps and extrusion steps envisaged in the production cycle. In particular, the possibility of varying the inclination at an angle comprised between 40° and 80°, preferably between 60° and 80°, for example 70°, can allow greater stability of the soft layer to be maintained during the displacement thereof from the decoration system up to reaching the press, thus obtaining the desired final product. In other words, the inclination of the texture comprised between 40° and 80°, preferably between 60° and 80°, for example 70°, allows greater structural stability of the texture itself within the soft layer to be obtained during the displacement envisaged by the production cycle. Therefore, during transport, the texture does not break inside the soft layer and the soft layer maintains its geometric characteristics.

[0010] The possibility of selecting an inclination with an angle greater than 40° also allows the finished product to be obtained with optical perception characteristics more similar to natural stone or wood.

[0011] Further characteristics and advantages of the present application will become better apparent from the following detailed description of an embodiment thereof, illustrated by way of non-limiting example in the accompanying drawings wherein:

[0012] - Figure 1 is a schematic view of a ceramic slab according to the present application;

[0013] - Figure 2 is a view of the ceramic slab of Figure 1 ;

[0014] - Figure 2a is a first enlarged view of the view of Figure 2 ;

[0015] - Figure 2b is a second enlarged view of the view of Figure 2 ;

[0016] - Figure 2c is a further enlarged view of the side of the ceramic tile of Figure 1 ;

[0017] - Figure 3 is a schematic view of a machine which can be used to produce the ceramic slab according to the present application;

[0018] -Figure 4 is Figure 3 an enlarged view of the area (B) of

[0019] - Figure 5 is Figure 3 an enlarged view of the area (A) of

[0020] In the following description, a ceramic slab means a product realized with known ceramic technology processes, which comprise the essential steps of extruding a layer of granular or powdery ceramic material and subsequent firing of the extruded layer, having a flat and squashed slab shape.

[0021] The ceramic slab comprises a body (100) realized in ceramic material, having a thickness (S) delimited by a first face (110) and a second face (120), which are substantially flat and parallel to each other. The first face (110), also called "face", is intended to remain exposed or visible after laying of the ceramic slab. The second face (120), also called "back face", is instead intended to come into contact with the laying surface of the ceramic slab. Typically, after installation of the ceramic slab for the intended use, the second face (120) remains substantially hidden.

[0022] Typically, the thickness (S) has an extension much smaller than the linear dimensions of the faces (110, 120). As an order of magnitude, the sides of the faces (110, 120) can range from 10 cm to more than 3 m, while the thickness is between about 5 mm and 30 mm. The body (100) also comprises four sides (130, 140, 150, 160) perpendicular to the first face (110) and to the second face (120).

[0023] The ceramic slab comprises at least one decoration (200) having a different color and / or shade with respect to the body (100), which extends at least partially in the thickness (S) of the body (100) and at least partially on one of the two faces (110, 120).

[0024] The decoration (200) mainly comprises one or more areas of the body (100) which are colored differently from the rest of the body (100). Different colorings can be obtained by laying ceramic materials of different composition and / or grain size and / or color. For example, the decoration (200) comprises one or more textures or streaks.

[0025] The decoration (200) is delimited, in a section substantially perpendicular to the faces (110, 120), by at least a first edge (210) which extends transversely between the faces (110, 120) along a main extension direction (SI); substantially perpendicular means a section which forms an angle comprised between about 80° and 90° with respect to the faces (110, 120).

[0026] Preferably, the decoration (200) emerges on at least one side of the body (100), i.e. the decoration is visible on at least one side of the body (100). In this case, the aforementioned section is coplanar with the side on which the decoration emerges, and the first edge (210) is also visible on the same side.

[0027] The main extension direction (SI) of the first edge (210) is substantially rectilinear, this straight line approximating the general trend of the first edge (210) between the two faces (110, 120). In other words, the main extension direction is the direction perceived by the eye when the tile is observed in the normal position of use, i.e. when the tile is placed with the two faces (110, 120) substantially horizontally laid.

[0028] In a possible definition, the main extension direction (SI) can be defined as the straight line passing through the two end points of the first edge (210), i.e. the two ends of the first edge (210). For example, with reference to Figure 2b , the main extension direction (SI) is the line passing through the first edge (210) and the intersection point between the corner (el, e2) of the side on which the first edge (210) lies.

[0029] Alternatively, the extension direction (SI) of the first edge (210) is the statistical interpolation straight line between a given number of points belonging to the first edge (210). In a known manner, once the points of the first edge (210) to be considered have been defined, the statistical interpolation straight line can be calculated using the least squares method as follows:

[0030] y = mx + q,

[0031] where

[0032]

[0033] The extension direction (SI) can still be defined or calculated by other methods.

[0034] The inclination angle (b) is defined between the extension direction (SI) and a plane substantially parallel to the faces (110, 120). By substantially parallel plane it is meant a plane forming an angle of between about 0° and 10° with respect to the faces (110, 120).

[0035] Advantageously, in the porcelain slab obtained by the method according to the present application, the inclination angle (a) is comprised between 40° and 80°. Within this range, the decor (200) presents an appearance of natural texture, in particular the texture present in natural stone materials. Therefore, when the porcelain slab is laid with at least one visible side surface, for example on a hearth or a step, also the side surface of the porcelain slab presents a natural appearance in line with the surface decor that can be applied to the first face (110). Moreover, the inclination angle (a) within the range comprised between 40° and 80° gives a considerable stability to the decor during the course of the production cycle, which leads to the realization of the porcelain slab starting from the laying of the decorative soft layer (L2), which will be better explained below. In particular, the decor remains stable with respect to the displacements undergone by the decorative soft layer (L2) from which the porcelain slab is obtained, and with respect to the extrusion steps to which the decorative soft layer (L2) itself is subjected.

[0036] In other words, it is possible to vary the inclination at an angle comprised between 40° and 80°, preferably between 60° and 80°, for example 70°, which can allow to maintain greater stability of the soft layer during the displacements of the soft layer required in the production cycle and with respect to the extrusion steps to which the decorative soft layer (L2) is subjected. In other words, the inclination of the texture comprised between 40° and 80°, preferably between 60° and 80°, for example 70°, allows to obtain greater structural stability of the texture itself within the soft layer during the various displacements. Therefore, during transport, the texture does not break inside the soft layer and the soft layer maintains its geometric characteristics.

[0037] The possibility of selecting an inclination with an angle greater than 40° also allows to obtain a finished product with optical perception characteristics more similar to natural stone or wood.

[0038] The Applicant has found that, although the first edge (210) can have a tendency to wind or angle, if the inclination angle (a) of the main extension direction (S1) is comprised between 40° and 80°, the decor (200) presents a completely natural appearance, substantially similar to the appearance of the texture in natural stone materials. With reference to Figure 2c In the example shown, the main extension line (S1) of the first edge (210) is defined as passing through the end of the first edge (210) itself, and the inclination comprised between 40° and 80° is assumed to give the decor (200) a completely natural appearance. Similar considerations can be made for the second edge (220) of the decor (200).

[0039] More preferably, the inclination angle (b) is comprised between 60° and 80°. Thus, the inclination angle (a) is relatively high, rather than vertical. In this case, the effect obtained is that of a more natural appearance of the decoration, which assumes an almost indistinguishable appearance from the texture of natural stone, when the slab is arranged in normal use conditions, i.e. with the faces (110, 120) of the slab lying on a substantially horizontal plane. Furthermore, the inclination angle (a) comprised between 60° and 80° further increases the stability of the decoration during the course of the production cycle, which leads to the realization of the slab, particularly with respect to the displacements undergone by the decorative soft layer (L2) from which the slab is obtained, and with respect to the extrusion step undergone by the decorative soft layer (L2) itself.

[0040] Even more preferably, the inclination angle (b) is comprised between 65° and 75°. Within this range, the technical effects and advantages described above are further improved. For example, the inclination angle (b) is approximately 70°.

[0041] In another possible embodiment, the decoration (200) is delimited, in a cross section perpendicular to the faces (110, 120), by a second edge (220) which extends transversely between the faces (110, 120) along a main extension direction (S2). In this case, the decoration (200) assumes an even more determined appearance of the texture with respect to the previous case. The main extension direction (S2) of the second edge (220) can be defined in the same way as already described with respect to the main extension direction (SI) of the first edge (210). If the decoration (200) appears on at least one lateral face of the body (100), i.e. is visible on at least one lateral face of the body (100), the second edge (220) is also visible on the same face.

[0042] A second inclination angle (b) is defined between the extension direction (S2) and a plane parallel to the faces (110, 120). Even this second inclination angle (b) is comprised between 40° and 80°. The advantages provided by an inclination comprised within the indicated range are the same as those already emphasized with respect to the first edge (210). Preferably, the second inclination angle (b) is comprised between 60° and 80°. This inclination makes the appearance of the slab even more similar to natural stone. Furthermore, for the same reasons already stated with respect to the main extension direction (SI) of the first edge (210), the inclination angle (b) comprised between 60° and 80° gives the decoration even greater stability during the course of the production cycle, which leads to the realization of the slab, particularly with respect to the displacements undergone by the decorative soft layer (L2) from which the slab is obtained, and with respect to the extrusion step undergone by the decorative soft layer (L2) itself. Even more preferably, the inclination angle (b) is comprised between 65° and 75°. Within this range, the technical effects and advantages described above are further improved. For example, the inclination angle (b) is approximately 70°.

[0043] It should be noted that another element that distinguishes the artificial decor from the natural decor present in natural stone is the high definition of the edges (210, 220). In fact, in the artificial decor, such edges are clean and do not have any shadow gradient towards the stone portion adjacent to the decor (200) itself.

[0044] The feature perceived in the decor (200) according to the present application consists in having edges (210, 220) with minimum shadow gradient, so that the observer feels as if he is in front of a natural stone. Advantageously, the main extension directions (SI, S2) can be substantially parallel or converging or diverging. In fact, the Applicant has observed that when the inclination angle (a, b) of each of the main extension directions (SI, S2) is between 40° and 80°, the natural appearance of the decor (200) is maintained regardless of the mutual inclination between the main extension directions (SI, S2).

[0045] By implementing the production method designed by the Applicant, the advantageous inclination of the extension directions (SI, S2) of the edges (110, 120) of the decor (200) of the porcelain slab obtained by the method according to the present application is obtained.

[0046] The method envisages arranging, on a first deposition plane (50), a decorative layer (L2) of granular or powdery ceramic material having a decor (200), gradually depositing the decorative layer (L2) from a head (H) to a tail (T).

[0047] The head (H) is formed by the material that is deposited first on the first deposition plane (50). The tail (T) is formed by the material that is deposited last on the first deposition plane (50). In Figure 4 In the example shown, the deposition of the decorative layer (L2) occurs with the first deposition plane (50) moving from right to left along the longitudinal direction (Y). By way of example only, during the laying of the decorative layer (L2), the first deposition plane (50) moves at a speed comprised between 0.5 meters per minute and 3 meters per minute.

[0048] Generally, considering the granulometric characteristics of the ceramic material usually used, at the speed range indicated above, the decor (200) on the first deposition plane (50) assumes an inclination angle (a, b) close to approximately 30°. Such an inclination angle is the inclination angle of the decor (200) before the extrusion step.

[0049] The method then envisages transferring the decorative layer (L2) from the first deposition plane (50) to a second deposition plane (83) located at a lower height than the first deposition plane (50). The transfer of the decorative layer (L2) starts from the tail (T). In other words, the tail (T) of the decorative layer (L2) is first deposited on the second deposition plane (83). With reference to the exemplary embodiment shown, the transfer of the decorative layer (L2) from the first deposition plane (50) to the second deposition plane (83) occurs in a direction from left to right, as shown. In other words, during the deposition of the soft layer (L2), the first deposition plane (50) moves in the opposite direction with respect to the transfer step to the second deposition plane (83) along the longitudinal direction (Y). Figure 5

[0050] The deposition of the decorative layer (L2) on the first deposition plane, while the first deposition plane (50) is moving, generates a displacement of the material along the longitudinal direction (Y) which is not equal along the thickness of the decorative layer (L2). In essence, thanks to this relative movement, the advancement of the decoration, which should present a certain inclination, with respect to the direction of advancement of the first deposition plane (50) is subjected to a backward tilting deviation.

[0051] The transfer of the decorative layer (L2) from the first deposition plane (50) to the second deposition plane (83), which occurs starting from the tail (T), generates a displacement of the material along the longitudinal direction (Y) opposite to the previous displacement. This then allows to change the inclination of the decoration (200), as schematically shown in Figure 5 In other words, the transfer of the decorative layer (L2) from the tail (T) allows to change or correct the inclination of the decoration (200), generating an effect opposite to that which generated the deviation of the decoration (200) during the deposition on the first deposition plane (50).

[0052] In essence, the decorative layer (L2) is deposited on the first deposition plane (50), starting from the head (H) up to the tail (T). In the solution depicted, this transfer occurs while the first deposition plane (50) moves from right to left. Once the deposition of the decorative layer (L2) is completed, the movement of the first deposition plane (50) is reversed and a second decorative layer (L2) is transferred to the second deposition plane (83), which moves in a direction coinciding with the first deposition plane (50). Therefore, the tail (T) of the decorative layer (L2) is first transferred and deposited on the second deposition plane (83).

[0053] ​The inclination of the decoration (200) obtained on the second deposition plane (83) after the transfer from the first deposition plane (50), i.e. the inclination angle (a) of the main extension direction (SI) of the first edge (210) and the inclination angle (b) of the main extension direction (S2) of the second edge (220), allows to obtain in the finished product an inclination angle comprised between 40° and 80°, or more preferably between 60° and 80°, or even more preferably between 65° and 75°, compensating the effect of the extrusion and of keeping the decoration (200) itself stable, which does not undergo further deformations in addition to the above-mentioned inclination correction.

[0054] In fact, the extrusion step generates a variation of the inclination angle (a, b) of the main extension direction (SI, S2). In particular, the extrusion reduces the inclination angle (a, b). By correcting the inclination angle (a, b) generated by the transfer from the first deposition plane (50) to the second deposition plane (83), it is possible to substantially predict and compensate this variation.

[0055] By varying the ratio between the speeds of the two deposition planes (50, 83), it is possible to further intervene on the inclination angle (a, b) of the main extension direction (SI, S2), and possibly to vary the thickness of the second layer (L3).

[0056] Preferably, the speed of the first deposition plane (50) and the speed of the second deposition plane (83) are in a predetermined ratio. This ratio is selected as a function of the structure of the decoration (200).

[0057] More preferably, the speed of the second deposition plane (83) is comprised between about half and twice the speed of the first deposition plane (50). By way of example only, during the step of transferring the decorative layer (L2) from the first deposition plane (50) to the second deposition plane (83), the advancement speed of the first deposition plane (50) and of the second deposition plane (83) is preferably comprised between 30 meters per minute and 50 meters per minute.

[0058] In other words, the ratio between the two speeds is predetermined with respect to the inclination angle (a, b) intended to be assigned to the main extension direction (SI, S2) and to the thickness that will be imparted to the second layer (L3).

[0059] Of course, it is also possible to obtain the desired inclination angle (a, b) of the main extension direction (SI, S2) during the transfer step with a speed of the first deposition plane (50) and a speed of the second deposition plane (83) that are substantially equal to each other. In this case, the thickness of the second layer (L3) remains unchanged.

[0060] Another control parameter that can be used, although not necessarily, to vary the inclination angle (a, b) is the speed of the first deposition plane (50) during the deposition of the decorative layer (L2).

[0061] During the deposition of the decorative layer (L2), the speed of the first deposition plane (50) influences to some extent the inclination angle (a, b) of the main extension direction (S1, S2) and the thickness of the decorative layer (L2). In the depicted embodiment, varying the speed of the first deposition plane (50) during the laying of the decorative layer (L2) allows to vary the inclination angle (a, b) of the main extension direction (S1, S2) in addition to varying the thickness of the decorative layer (L2).

[0062] As already indicated, during the deposition step of the decorative layer (L2), the first deposition plane (50) is moved along the longitudinal direction (Y) in the opposite direction with respect to the transfer step to the second deposition plane (83). Advantageously, during the deposition step of the decorative layer (L2) and during the transfer step to the second deposition plane (83), the first deposition plane (50) can be operated at different speeds, moduli and in reverse. This allows a further degree of control of the inclination angle (a, b) of the main extension direction (S1, S2) which can be used to increase the precision of the obtained result.

[0063] Preferably, the first deposition plane (50) can be moved at a lower speed during the step of depositing the decorative layer (L2) and at a higher speed during the transfer step.

[0064] Even more preferably, the speed during the step of depositing the decorative layer (L2) is between 1 / 100 and 1 / 10 of the speed during the transfer step to the second deposition plane (83). Thus, the desired inclination angle (a, b) can be obtained even more precisely.

[0065] By way of example only, during the step of depositing the decorative layer (L2), the speed of the first deposition plane (50) is between 0.5 meters per minute and 3 meters per minute, while during the transfer step to the second deposition plane, the speed is between 30 meters per minute and 50 meters per minute.

[0066] In a preferred embodiment of the method, the step of arranging the decorative layer (L2) on the first deposition plane (50) comprises the step of arranging a first soft layer (L1 ) of granular or powdered ceramic material on the decorative plane (10). The first layer (L1 ) has the decorations (200).

[0067] The method then envisages transferring the first layer (L1 ) from the decorative plane (10) to the first deposition plane (50) which is located at a lower height than the decorative plane (10). As Figure 4 indicated, the transfer occurs by gradual deposition. Essentially, the gradual transfer causes the first layer (L1 ) to be deposited on the first deposition plane (50) gradually forming the decorative layer (L2) having a head (H) and a tail (T).

[0068] In an alternative embodiment, not shown, the deposition of the decorative layer (L2) on the first deposition plane (50) occurs through another type of dispensing device, able to dispense the ceramic product towards the deposition plane (50) in a controlled manner.

[0069] In the embodiment shown, the decorative plane (10) is in the form of a flexible belt, movable along a closed path rotating around a pair of rollers (31, 32). Along the path defined by the rollers (31, 32), the decorative plane (10) has an upper section (10a) along which it slides forward in the longitudinal direction (Y) and along which the first layer (LI) can be laid. In the section rotating around the front roller (31), the first layer (LI) flows gradually downwards on the first deposition plane (50), forming the decorative layer (L2) starting from the head region (H) to the tail region (T). In the solution depicted, the first deposition plane (50) is movable in the opposite direction with respect to the upper section (10a) of the decorative plane, in the longitudinal direction (Y). Other solutions are also possible, in which the movements of the decorative plane (10) and of the deposition plane (50) are consistent, or in which the deposition plane (50) is fixed and the decorative plane (10) is movable with respect to the deposition plane (50) in the longitudinal direction (Y) in addition to sliding in the longitudinal direction (Y).

[0070] Preferably, but not necessarily, the accumulation container (F) is interposed between the decorative plane (10) and the first deposition plane (50), as Figure 4 As shown, the accumulation container (F) comprises an unloading opening (O) arranged to allow the deposition of the ceramic compound on the first deposition plane (50). The interposition of the accumulation container (F) between the decorative plane (10) and the deposition plane (50) is advantageous to preserve the structure of the decoration (200).

[0071] The ceramic compound coming from the decorative plane (10) passes through the accumulation container (F) before being deposited on the deposition plane (50). Therefore, instead of being directly transferred towards the first deposition plane (50), the ceramic compound is temporarily accumulated inside the accumulation container (F) before being deposited on the first deposition plane (50). The amount of compound accumulated inside the container (F) depends substantially on the area of the unloading opening (O) and on the flow rate of the compound unloaded from the decorative plane (10).

[0072] The transfer of the decorative layer (L) from the first deposition plane (50) to the second deposition plane (83) occurs preferably according to the solution described in the publication WO2017051275. According to this solution, the first deposition plane (50) is substantially aligned and contiguous at a higher level with respect to the second deposition plane (83).

[0073] As can be seen in Figure 1 The first deposition plane (50) comprises a front end portion (51) which defines an end portion at which the first deposition plane (50) defines a return curve. Such front end portion (51) at least partially covers a rear end portion (83a) of the second deposition plane (83). By operating in the agreed advancement direction, i.e. in the same advancement direction, in the first deposition plane (50) and in the second deposition plane (83), the second decorative layer (L2) is transferred from the first deposition plane (50) to the second deposition plane (83), performing a modest jump downwards at the front end portion (51) of the deposition plane (50) and gradually forming the second layer (L3). The deposition plane (50) and the movable plane (83) are movable independently of each other, i.e. each of them is provided with motor means which are operable independently of the other.

[0074] The machine comprises first motor means arranged to implement a first relative movement between the decorative plane (10) and the first deposition plane (50) directed along the longitudinal direction (Y). The machine further comprises second motor means arranged to implement a second relative movement between the first deposition plane (50) and the second deposition plane (83) directed along the longitudinal direction (Y). The first motor means and the second motor means are operable independently of each other.

[0075] The decorative plane (10) comprises a plurality of cavities having a predetermined shape and depth or height. Each of such cavities has an opening which allows the entry of the powder material and the subsequent unloading of the previously introduced powder material. Each cavity is delimited by a lateral wall and by a bottom which can be substantially flat or curved.

[0076] The decorative plane (10) can be implemented in the form of a flat element, in the thickness of which the cavities are obtained. Alternatively, the cavities can be structured in such a way that they can be applied to the decorative plane (10). In one possible embodiment, the decorative plane (10) comprises a layer of flexible material, for example rubber or plastic material, in the thickness of which the cavities are obtained. In one particularly advantageous embodiment, the decorative plane (10) comprises a flexible strip on which the cavities are obtained which open onto the surface of the strip itself. Preferably, but not necessarily, the cavities are mutually identical and distributed in a regular manner on the decorative plane (10). The cavities are adjacent to each other along their lateral faces, so as to be separated by relatively thin edges. In other words, each cavity defines a volume suitable for receiving a predetermined amount of powder material for the decoration to be implemented. Each cavity can be filled in a manner independent of the other cavities.

[0077] In the preferred, but not exclusive, embodiment shown, the decoration plane (10) is in the form of a flexible belt closed in a loop around a pair of rollers (31, 32). The cavities face the outside of this closed path. Along the path defined by the rollers (31, 32), the decoration plane (10) has an upper section (10a) along which it advances in the longitudinal direction (Y) and along which the cavities face upwards in the loading position. The dispensing device (20) can be placed on top of the decoration plane (10), i.e. above the upper section of the decoration plane (10), so as to be able to unload the powder material downwards and towards the cavities.

[0078] Loading of the cavities takes place during the advancing movement of the decoration plane (10) in the longitudinal direction (Y). Essentially, as the decoration plane (10) advances, the dispensing device (20) sends the powder material to the cavities in a selective and targeted manner through the unloading openings or nozzles. This allows the powder material contained in the dispensing device to be transported towards the predetermined cavities and not towards the other cavities.

[0079] As already indicated, the rollers (31, 32) cause the decoration plane (10) to slide along the closed path so as to gradually displace the cavities from the loading position to the unloading position. In the passage from the loading position to the unloading position, the cavities pass from their position facing upwards to their position facing downwards. During this passage, each cavity can pour its contents downwards. As Figure 4 The passage of the cavities from the loading position to the unloading position takes place gradually along the section of the decoration plane (10) that turns around the first roller (31), as shown schematically. The pouring of the contents is substantially complete when each cavity is positioned facing downwards, i.e. after having travelled around the first roller (31). By turning around the second roller (32), the cavities are moved back to the loading position to receive a new load of powder material.

[0080] In the solution shown, a first deposition plane (50) is placed below the decoration plane (10) for receiving the powder material unloaded by the cavities. Relative movement directed in the longitudinal direction (Y) is provided between the decoration plane (10) and the first deposition plane (50), which takes place simultaneously with the unloading of the powder material from the cavities. This allows the powder material unloaded from the cavities to be deposited in a continuous layer (L2) on the first deposition plane (50).

[0081] In a preferred embodiment, the relative movement between the first deposition plane (50) and the decoration plane (10) is obtained by sliding the first deposition plane (50) along the longitudinal direction (Y), while the decoration plane (10) is overall stationary along the direction (Y), although it can slide along its path around the rollers (31, 32). The sliding of the first deposition plane (50) can be in the same direction or in the opposite direction with respect to the sliding of the upper section of the decoration plane (10) in its movement around the rollers (31, 32). Preferably, but not necessarily, the first deposition plane (50) is in the form of a belt that is slidably movable along a closed path defined by two or more rollers, as shown in Figure 1

[0082] Preferably, the control processor is arranged to control the dispensing devices (20) so as to fill the cavities related to the decoration (200) to be implemented in the layer (LI). To this end, the control processor is provided with an algorithm that allows processing the image of the decoration (200) to decompose it into a series of volumes of powder material of predetermined color, each volume being attributed to a predetermined cavity. Then, the control processor regulates the operation of the dispensing devices (20) so that each volume is introduced into the predetermined cavity. The correspondence between each volume and the corresponding cavity is established by making the control processor aware of the position of each cavity, the speed of the decoration plane (10) and the speed of the first deposition plane (50), for example by means of encoders, sensors or optical systems known in the art. Essentially, starting from the decoration (200) to be implemented, the control processor defines the number and position of the volumes of material necessary to obtain it and attributes each volume to a cavity with respect to the position in which the volume will be unloaded on the first deposition plane (50) with respect to the volumes contained in the cavities.

[0083] The second deposition plane (83) can be used to direct the soft layer of decoration (L3) to the press (80). For example, the press (80) is in the form of a belt press, known in the art for extruding large-format slabs. This type of press comprises a bottom pad (81) provided with an upward-facing extrusion surface. A top pad (82) provided with a downward-facing extrusion surface is located above the bottom pad. At least one of the two pads is movable with respect to the other, closer and farther away, so as to perform the extrusion of the layer (L3) of powder-ceramic material. The press further comprises a movable plane (83) in the form of a flexible belt having a free section (84) arranged at least partially between the top pad (82) and the bottom pad (81). The press further comprises a second movable plane (85) in the form of a flexible belt having a free section (86) arranged between the free section (84) of the first movable belt (83) and the top pad (82).

[0084] After the extrusion, the ceramic slab can be transported to a furnace for the firing step.​

Claims

1. A method for implementing a porcelain plate, comprising the steps of: arranging a decorative soft layer (L2) having decorations (200) on a first deposition plane (50), gradually depositing the decorative soft layer (L2) from a head portion (H) to a tail portion (T); gradually transferring the decorative soft layer (L2) from the first deposition plane (50) by deposition to a second deposition plane (83) placed at a lower height than the first deposition plane (50), gradually implementing a second layer (L3) on the second deposition plane (83) starting from the tail portion (T) of the decorative soft layer (L2); wherein the speed of the first deposition plane (50) during the step of depositing the decorative soft layer (L2) is lower than the speed during the step of transferring the decorative soft layer (L2) from the first deposition plane (50) to the second deposition plane (83); wherein the speed of the first deposition plane (50) during the step of depositing the decorative soft layer (L2) is 1 / 100 to 1 / 10 of the speed during the step of transferring the decorative soft layer (L2) from the first deposition plane (50) to the second deposition plane (83); wherein, during the deposition of the decorative soft layer (L2), the first deposition plane (50) moves in the opposite direction with respect to the transfer step to the second deposition plane (83) along the longitudinal direction (Y).

2. The method of claim 1, wherein, During the transfer of the decorative soft layer (L2) from the first deposition plane (50) to the second deposition plane (83), the first deposition plane (50) and the second deposition plane (83) move at respective speeds along the longitudinal direction (Y).

3. The method of claim 2, wherein, The speed of the first deposition plane (50) and the speed of the second deposition plane (83) are in a predetermined ratio.

4. The method of claim 3, wherein, The speed of the second deposition plane (83) is between half and twice the speed of the first deposition plane (50).

5. The method of claim 1, wherein, The step of depositing a decorative soft layer (L2) having decorations (200) on a first deposition plane (50) comprises the steps of: arranging a first soft layer (L1) on a decoration plane (10); gradually transferring the first soft layer (L1) from the decoration plane (10) to the first deposition plane (50) placed at a lower height with respect to the decoration plane (10).

Images