Patent Application
20240391137
This Patent Application claims priority from Italian Patent Application No. 102021000024380 filed on Sep. 22, 2021 the entire disclosure of which is incorporated herein by reference.
The present invention relates to a decoration method and system for the surface decoration of a base ceramic article.
In particular, the present invention relates to a method and system for the decoration of slabs comprising (consisting of) ceramic material; still more particularly, of tiles comprising (consisting of) ceramic material.
In the field of manufacturing ceramic articles, particularly ceramic slabs and tiles, it is known to submit base ceramic articles to surface treatments adapted to give the article the desired aesthetic, mechanical and functional properties.
The most widespread surface treatments are decoration treatments adapted to give the base ceramic article the desired aesthetic appearance. In recent years, there has been a widespread tendency to try to reproduce the appearance of natural stone or wood, etc. by imprinting the base ceramic article with a three-dimensional pattern in addition to a chromatic decoration that reproduces the surface coarseness and/or irregularities and/or roughness of natural stone, wood, etc., thus giving a more natural appearance to the ceramic article.
Some known systems for decorating ceramic articles provide for imprinting a three-dimensional pattern on at least one surface of a base ceramic article during the ceramic powder pressing step. In particular, such known systems provide that at least one of the two half moulds of the pressing device intended to form the base ceramic article is configured to imprint a certain three-dimensional pattern on the surface of the base ceramic article during pressing. The base ceramic article thus formed (i.e. already having a three-dimensional pattern on a surface) is then further decorated by applying a chromatic decoration, e.g. using an inkjet printer, and is subsequently submitted to drying and firing so as to obtain a finished ceramic product.
Other known decoration systems comprise firstly pressing ceramic powder and drying the base ceramic articles and then decorating the dried ceramic article by means of a decoration device that selectively applies adhesive and granular material to a surface of the base ceramic article to form the three-dimensional pattern and a subsequent printing device that prints an image (chromatic decoration) on the three-dimensional pattern to reproduce a certain final decoration. The base ceramic article thus decorated is then fired so as to obtain a finished ceramic product.
However, the known decoration systems comprise printing an image on the base ceramic article having a certain three-dimensional pattern regardless of the actual three-dimensional structure on the article itself and/or the actual orientation of the ceramic article. This often results in base ceramic articles decorated with the known machines and methods described above having a three-dimensional pattern that does not appear to be in synchrony with the image or chromatic decoration printed on it. It is clear that this compromises the final aesthetic appearance of ceramic products.
In addition, decoration systems and methods of the known type have another technical drawback related to the fact that the adhesive material and/or ink used for creating the three-dimensional pattern and/or the chromatic decoration, warming up when in contact with the hot surface of the freshly dried base ceramic article or during the firing step, induces (induce) the emission of toxic and often bad-smelling waste products, which must be sucked and appropriately treated with expensive filtration (or abatement) systems to ensure the safety and healthiness of the environment and to comply with the environmental regulations in force.
The aim of the present invention is to provide a decoration method and system for the decoration of a base ceramic article, which allow to overcome, at least partially, the drawbacks of the prior art while being easy and cheap to implement.
In accordance with the present invention, a decoration method and system are proposed for decorating a base ceramic article as claimed in the attached independent claims, and preferably, in any one of the claims dependent directly or indirectly on the mentioned independent claims.
The claims describe preferred embodiments of the present invention forming an integral part of the present description.
The invention is hereinafter described with reference to the accompanying drawings, which show some non-limiting embodiments thereof, wherein:
In
According to some preferred but not exclusive embodiments such as the one shown in
In detail, according to some non-limiting embodiments such as the one shown in
In this case, advantageously but not necessarily, the conveyor assembly 2 comprises a conveyor device 9, for example comprising a belt conveyor (as in
According to other embodiments of the invention, the plant 1 comprises a conventional tile pressing machine (of a known type) which is configured to receive a defined amount of powder material CP comprising (in particular, mainly consisting of) ceramic powder and to compact it so as to generate a slab of compacted ceramic powder KP having at least one surface 7 to be decorated at each pressing cycle; which slab of compacted ceramic powder KP is then moved, for example by means of the conveyor device 10 from the work station 5 towards (through) a decoration system 11 for the decoration of the base ceramic article CB. Typically, such a conventional pressing machine is provided with a vertical-axis hydraulic pressing device adapted to press powder ceramic material so as to directly obtain individual slabs (which do not require cutting) of pressed material.
Advantageously, in the present discussion, the term base ceramic article CB refers to at least one portion of (in particular, of each) slab of compacted ceramic powder KP having the above-mentioned surface 7 to be decorated.
Furthermore, in the present discussion, “surface 7 to be decorated” refers to the surface of (each) slab of compacted ceramic powder KP (i.e. the base ceramic article CB) that is intended, in use, to be in view (i.e. exposed); in particular, the surface 7 to be decorated is the surface facing upwards while being conveyed by the conveyor assembly 2, i.e. the surface 7 of the slab of compacted ceramic powder KP that is parallel to the conveying plane defined by the conveyor assembly 2, in particular by the conveyor device 10, but is not in contact with it during the movement along the given path P.
Advantageously, but not limitatively, the conveyor device 10 is configured to convey the (each) slab of compacted ceramic powder KP along a second section PB of the given path P, downstream of the section PA, (coming out) from the work station 5 to the output station 12, through the decoration system 11 (which is part of the plant 1); in particular, through at least the first decoration station 13 and the second decoration station 14.
According to some advantageous non-limiting embodiments such as the one shown in
Advantageously but not limitatively, the adhesive material 17 is a water-based glue. Specifically, (according to some advantageous but non-limiting embodiments) it is a glue comprising (even more in particular consisting of) about 50% by weight of Glycol, about 20% by weight of Water, about 30% by weight of inorganic part. The use of a water-based adhesive material thus made reduces the risk of hazardous emissions during drying, while ensuring good adhesion of the granular material 22 that is applied on the layer 16 (as will be better described hereinafter).
Additionally, advantageously but not necessarily, the printing assembly 15 comprises an ink-jet head (ink-jet not visible in the accompanying Figures and known in itself and therefore not further described herein) configured to emit one or more jets of adhesive material 17 (selectively) onto the surface 7 to be decorated. In this case, advantageously but not necessarily, the adhesive material 17 is such (i.e. has such a texture and viscosity) that it can be applied by an ink-jet head.
In particular, according to some advantageous but not exclusive embodiments, the printing assembly 15 is configured to apply the layer 16 (in particular selectively) on the surface 7 to be decorated, at least on a defined part of the surface 7 to be decorated.
In detail, according to some advantageous but non-limiting embodiments such as the one shown in
According to other non-limiting and not illustrative variants, the printing assembly 15 is configured to apply (in particular, digitally) the adhesive material 17 so as to reproduce a defined pattern on the surface 7 to be decorated. In other words, the printing assembly 15 is configured to apply adhesive material 17 so that the layer 16 defines a pattern on the surface 7 to be decorated.
Advantageously, the decoration system 11 further comprises a first digital depositing assembly 20, which is arranged at the decoration station 13 downstream of the printing assembly 15 and is configured to deposit a second layer 21 comprising (in particular, consisting of) at least one first granular material 22, comprising granules and/or enamel atomized particles, selectively on the first layer 16 so as to adhere to the first layer 16 and to form an at least partially relief pattern on the surface 7 to be decorated of the (in particular, of each) slab of compacted ceramic powder KP (see for example
In the present discussion, “at least partially relief pattern” refers to a three-dimensional decoration made on the surface 7 to be decorated; in particular, the “at least partially relief pattern” could comprise a succession of elevations of different shape and trend arranged to form a three-dimensional structure/decoration, for example composed of a plurality of veins, striations, motifs, etc. in order to reproduce the real appearance of natural stones, wood or in general to reproduce any three-dimensional structure. According to some preferred but not limiting embodiments such as those shown in
Alternatively, according to some advantageous but non-limiting embodiments not shown, the layer 21 of granular material 22 is selectively deposited on the layer 16 at only a portion of the aforementioned defined part of the surface 7 to be decorated so as to adhere to the layer 16 and form the aforementioned at least partially relief pattern.
More precisely, advantageously but not necessarily, the decoration system 11 also comprises a control assembly 25 (see
According to some non-limiting and non-shown embodiments, the control assembly 25 is configured to control (in particular, digitally) the depositing assembly 20 to reproduce a defined pattern on the layer 16. In particular, when the layer 16 is such as to reproduce a pattern on the surface 7 to be decorated, the two patterns (the one defined by the layer 16 and the one defined by the layer 21) may coincide at least partially with each other. In these cases, the control assembly 25 is advantageously but not necessarily configured to also control the printing assembly 15. Specifically, advantageously but not necessarily, the distribution of the granular material 22 on the layer 16 may appear to be wider than the distribution of the adhesive material 17 on the surface 7 to be decorated, as it may be advantageous to deposit an amount of granular material 22 slightly in excess if compared to what is required (in order to reduce the risk that areas where the presence of the powder material 22 is appropriate remain without the required amount).
According to alternative embodiments, the distribution of the granular material 22 on the layer 16 may appear less wide than the distribution of the adhesive material 17 on the surface 7 to be decorated (in other words, the pattern defined by the layer 21 may be less wide than the pattern defined by the layer 16). In such a case, in the part of the pattern defined by the layer 16 on which the granular material 22 is not deposited, another granular material, different from the granular material 22, may, for example, be deposited in the same application step or in subsequent application steps (i.e. from the same depositing assembly 20 or from another depositing device).
Advantageously but not necessarily, in accordance with the non-limiting embodiment shown in
Still more specifically, advantageously but not necessarily, the depositing device 26 comprises a plurality of actuators 30, each of which is adapted to move a respective distribution element 29 between a closed position, wherein the respective distribution element 29 blocks the passage of the granular material 22 through the area of the output mouth 28 wherein it is arranged, and an open position, wherein the respective distribution element 29 allows the passage of the granular material 22 through the area of the outlet mouth 28 wherein it is arranged.
It should be noted that by using the depositing device 26 it is possible to obtain a more precise deposition (also in terms of thickness) of the granular material 22 and thus it is possible to more precisely define the three-dimensional pattern on the surface 7 to be decorated.
According to some non-limiting embodiments, the depositing assembly 20 is made as described in Patent application WO2009118611 and/or in Patent IT1314623 (by the same Applicant).
According to some advantageous but non-limiting embodiments, the first granular material 22 comprising granules and/or enamel atomised particles comprises (in particular, consists of) material having a particle size ranging from about 50 μm to about 500 μm; more advantageously from about 90 μm to about 300 μm.
Furthermore, according to some advantageous, non-limiting and non-shown embodiments, the granular material 22 comprises a first type of granules and/or atomised particles and a second type of granules and/or atomised particles, which differs from the first type in size and/or mechanical/physical characteristics. Such different types of granules and/or atomised particles may be at least partially overlapping each other or may be arranged on different areas of the layer 16 of adhesive material 17, depending on the type of partially relief pattern to be formed. In particular, advantageously but not limitatively, the first and second types of powder material 22 differ from each other in mechanical/physical characteristics, e.g. grain size.
In such cases, advantageously but not necessarily, the depositing assembly 20 comprises two or more depositing devices 26 that are equal and placed side by side and arranged in sequence along the given path P, one intended to deposit a first type of granular material 22 and the other intended to deposit a second type of granular material 22. Alternatively, the depositing assembly 20 may comprise a single depositing device 26, such as the one described above, whose container 27 is filled with granular material 22 of the two different types in subsequent steps.
Advantageously, the decoration system 11 comprises at least one further printing assembly 31, which is arranged at the second decoration station 14 and is configured to apply a third layer 32, which comprises (in particular, consists of) an ink and/or coloured powder particles on the second layer 21 so as to form a defined image (i.e. a chromatic pattern) on the at least partially relief pattern.
According to some advantageous but non-limiting embodiments, the third layer 32 comprises (in particular, consists of) water-based ink. In detail, advantageously but not limitatively, such a water-based ink comprises at least about 20% and up to about 30% of water; in particular, about 25% of water. An example of a water-based ink comprising (in particular, constituting) the above-mentioned layer 32 comprises (in particular, consists of): from about 20% to about 30%, in particular about 30%, of inorganic solid material (e.g., coloured ceramic powder and/or ceramic frit); from about 30% to about 50%, in particular about 45%, of a medium e.g., glycol-based; and from about 20% to about 30%, in particular about 25%, of water.
Advantageously but not limitatively, such printing assembly 31 has a structure and operation similar to the printing assembly 15.
Advantageously, as shown in the non-limiting embodiment of
Advantageously, the plant 1 (in particular, the decoration system 11) also comprises a dryer 34 which is arranged at a second work station 35, downstream of the first decoration station 13 and upstream of the second decoration station 14 along the given path P; which dryer 34 is configured to heat the (in particular, each) slab of compacted ceramic powder KP having the above-described at least partially relief pattern to a temperature of at least about 100° C. (in particular, of at least about 150° C.; even more particularly, to at least about 180° C.).
Furthermore, advantageously (as shown in the non-limiting embodiment of
According to some advantageous but non-limiting embodiments of the invention, the decoration system 11 also comprises at least another printing assembly 38 which is arranged downstream of the decoration station 13 and upstream of the second decoration station 14 and applies a fourth layer 39 comprising (in particular, consisting of) a fourth material, which comprises (in particular, consisting of) a coating material, in particular a liquid enamel or engobe, on the second layer 21.
This additional layer 39 makes it possible to even out the surface 7 to be decorated after creating the at least partially relief pattern and at the same time to reduce the risk of the granular material 22 moving on the slab of compacted ceramic powder KP, e.g. in the subsequent decoration steps, compromising the aesthetic appearance of the decoration.
Advantageously, but not limitatively (as in the non-limiting embodiment shown in
According to other advantageous but non-limiting embodiments, the printing assembly 38 has a structure and operation similar to the printing assembly 15 and printing assembly 31.
According to other advantageous but non-limiting embodiments not shown, the printing assembly 38′ is arranged immediately downstream of the depositing assembly 20 and immediately upstream of the dryer 34. In other words, the fourth layer 39 of material comprising enamel/engobe may be applied at the first decoration station 13. Alternatively, such additional printing assembly 38′ could apply a white ink instead of enamel/engobe.
Alternatively or in combination, advantageously but not limitatively, the decoration system 11 could comprise a printing assembly 38 arranged immediately downstream of the dryer 34 and a further printing assembly 38′ (similar to the printing assembly 38) arranged immediately downstream of the depositing assembly 20 and immediately upstream of the dryer 34 (as shown in
According to still other embodiments, the depositing assembly 20 could be configured to deposit (also) a layer 39 of material comprising (in particular, consisting of) white ink, which (advantageously but not limitatively) could replace the aforementioned enamel/engobe.
According to some advantageous but non-limiting and non-shown embodiments, the decoration system 11 comprises a further printing assembly (not shown and having the same structure and same operation as the printing assembly 15) arranged downstream of the depositing assembly 20 and configured to apply another layer comprising (in particular, consisting of) adhesive material on the layer 21 of granular material 22. Such an additional layer would be useful to ensure that any granular material 22 that had not adhered to the underlying layer 16 is blocked, thus minimising the risk of undesirable movement of granular material 22 that could soil components of the decoration system 11 or compromise the at least partially relief pattern. Alternatively, such an additional layer of adhesive material could receive additional granular material 22 by an additional depositing assembly (advantageously similar to the depositing assembly 20). In other words, as mentioned above, the at least partially relief pattern could be formed by several layers of adhesive material 17 and granular material 22 arranged in succession on the surface 7 to be decorated by several printing and depositing assemblies, advantageously digital, arranged in sequence along the given path P.
According to further advantageous but non-limiting embodiments such as those shown in
More precisely, according to some non-limiting embodiments, such a removal device 40 comprises a suction mouth designed to suck upwards the granular material 22 not adhered to the layer 16. Alternatively, the removal device 40 could be configured to remove the excess granular material 22 by blowing.
It is to be understood that the decoration system 11 may comprise any number of depositing and printing assemblies, and possibly removal devices, made according to any one of the embodiments described above, arranged in sequence so as to produce a partially multilayer relief pattern on the surface 7 to be decorated.
Furthermore, according to some advantageous but non-limiting embodiments not shown, the decoration system 11 comprises a final printing assembly 41 arranged downstream of the printing assembly 31, even more advantageously upstream of the kiln 36, along the given path P and configured to apply a final layer 42 comprising (in particular, consisting of) a coating material comprising (in particular, consisting of) a liquid enamel or engobe, on the layer 32 to cover it, in particular on the given decoration formed on the surface 7 to be decorated to cover it.
Advantageously, the coating material of the layer 42 may be any material, e.g., a fixative material, or a material such as to provide the surface 7 to be decorated with special aesthetic properties (e.g., special gloss) and/or functional properties (e.g., special roughness).
According to some advantageous but non-limiting embodiments such as the one shown in
In detail, according to some advantageous but non-limiting embodiments, the structure detection device 44 comprises (in particular, consists of) a vision device, e.g. a camera or laser scanner. It is understood that any detection device that allows to identify the at least partially relief pattern could be used.
Alternatively or additionally, the detection assembly 33 further comprises at least one positioning device (i.e., centring device) known in itself and not shown that is configured to move the (in particular, each) slab of compacted ceramic powder KP with respect to the moving direction A and the control assembly CU is configured to control the positioning device (i.e., centring device) depending on what is detected by the first position detector 43 so that at least one (in particular, each) slab of compacted ceramic powder KP assumes a given position (orientation) with respect to the moving direction A. In detail, advantageously but not limitatively, the control assembly CU is configured to control the positioning device (i.e., centring device) so that it centres the (each) slab of compacted ceramic powder KP with respect to the moving direction A entering the second decoration station 14.
In detail, according to some advantageous though non-limiting embodiments, the positioning (i.e., centring) device comprises a plurality of movable barriers configured to act on the (in particular on each) slab of compacted ceramic powder KP, such as along the side edges of the (in particular, of each) slab of compacted ceramic powder KP and vary the orientation thereof with respect to the moving direction A. It is understood that any other positioning device of the known type may be used for the same aim.
Alternatively, advantageously but not limitatively, the data detected (i.e. collected) by the positioning (i.e. centring) device are also used by the control assembly CU to control the printing assembly 31.
According to still other non-limiting embodiments such as that schematically shown in
Alternatively, advantageously but not limitatively, the data detected (i.e. collected) by the additional position detector are also used by the control assembly CU to control the printing assembly 15 and the depositing assembly 20 via the control assembly 25. In detail, in this case, the control assembly CU exchanges data with control assembly 25, which according to some embodiments is part of the control assembly CU and according to other embodiments coincides with the control assembly CU (i.e. there is only one control assembly that controls both the printing assembly 31 as well as the printing assembly 15 and depositing assembly 20).
According to some advantageous but non-limiting embodiments, the decoration system 11 comprises a writing device (known in itself and not further described or shown herein) arranged downstream of the first decoration station 13 and configured to associate an identification code (in particular, a barcode or QRcode) to (in particular, to each) slab of compacted ceramic powder KP; and a reading device (known in itself and not further described or shown herein) that reads the identification code related to the (in particular, with each) slab of compacted ceramic powder KP to identify it. In this case, the control assembly CU is configured to operate (i.e. control; in particular digitally) the printing assembly 31, based (also) on what is detected by the reading device.
More precisely, when present, the writing device is advantageously but not limitatively arranged upstream of the first decoration station 13 along the given path P (and even more advantageously it is part of the second detection assembly 45), while the reading device is arranged (immediately) upstream of the second decoration station 14 (and still more advantageously is part of the detection assembly 33).
Due to the presence of the writing device and the reading device, advantageously but not limitatively, the control assembly CU operates the printing assembly 31 not only based at least on what is detected by the detection assembly 33 (in particular, by the first structure detecting device 45), but also based on the identification code read by the reading device.
In accordance with a further aspect of the present invention, there is also provided a decoration method for decorating a ceramic article CB having at least the surface 7 to be decorated.
Advantageously, the method comprises: a first processing step during which a layer of powder material CP comprising (in particular, consisting of) ceramic powder is processed by a work assembly 4, which is advantageously arranged at a work station 5 and comprises at least one compaction machine 6 (advantageously made according to one of the variants described above and) configured to compact the layer of powder material CP so as to obtain at least one slab of compacted powder KP having at least one surface 7 to be decorated, which is intended, in use, to be in view, i.e. exposed (as better explained above with reference to the decoration system 11).
The method further comprises: an moving step, during which the (in particular, each) slab of compacted ceramic powder KP is moved by a conveyor assembly 2 (of the type described above), in particular by a conveyor device 10, along a given path P in a moving direction A from (exiting) the work station 5 to an output station 12, through at least a first decoration station 13 and a second decoration station 14 arranged downstream of the first decoration station 13; a first application step, during which a first printing assembly 15 (advantageously of the type described above) arranged at the first decoration station 13 applies a first layer 16 comprising (in particular, consisting of) a material 17, which comprises (in particular, is) an adhesive material, in correspondence with at least a part of the surface 7 to be decorated of the (in particular, of each) slab of compacted ceramic powder KP; and at least a second application step, at least partially subsequent to the first application step, during which at least a first digital depositing assembly 20 of the type described above, arranged at the first decoration station 13 downstream of the printing assembly 15 along said given path P, deposits at least a second layer 21 comprising (in particular, consisting of) at least one granular material 22, comprising granules and/or enamel atomized particles, selectively on the first layer 16 so as to adhere to the first layer 16 and to form an at least partially relief pattern (of the type described above) on the surface 7 to be decorated.
As mentioned above in relation to the decoration system 11, according to some advantageous but non-limiting embodiments, the first granular material 22 comprising granules and/or enamel atomised particles comprises (in particular, consists of) material having a particle size ranging from about 50 μm to about 500 μm; more advantageously from about 90 μm to about 300 μm
In detail, in accordance with the non-limiting embodiment shown in
As already mentioned in relation to the decoration system 11, during the first application step, the printing assembly 15 may apply the layer 16 at the entire surface 7 to be decorated or at a portion of the surface 7 to be decorated; and during the second application step, the depositing assembly 20 deposits the layer 21 comprising the (in particular, consisting of the) granular material 22 selectively on the layer 16 in correspondence of at least a portion of said part so as to adhere to the layer 16 and define the above-described at least partially relief pattern on the surface 7 to be decorated.
Moreover, as already mentioned in relation to the decoration system 11, the method may comprise several successive application steps, during which further printing assemblies apply further layers of adhesive material 17 and further depositing assemblies deposit further granular material 22 on the previously laid layers of adhesive material to form the at least partially relief pattern.
The method further comprises a drying step, subsequent to the first and second application steps, during which the slab of compacted ceramic powder KP is dried within a dryer 34 arranged at a second work station 35, downstream of the first decoration station 13 along the given path P and at least a third application step, during which a second printing assembly 31, arranged at a second decoration station 14 downstream of the second work station 35, applies a third layer 32 comprising (in particular, consisting of) a second material, which comprises (in particular, consists of) at least one ink and/or coloured powder on the second layer 21 so as to form a defined image on the at least partially relief pattern formed in the second application step.
As mentioned above in relation to the decoration system 11, according to some advantageous but non-limiting embodiments, the third layer 32 comprises (in particular, consists of) water-based ink. In detail, such a water-based ink (which advantageously but not limitatively may be like the one described above as an example) comprises at least about 20% and up to about 30% of water, in particular about 25% of water.
Advantageously, but not limitatively, during the drying step, the (in particular, each) slab of compacted ceramic powder KP having the at least partially relief pattern described above is heated in relief to a temperature of at least about 100° C. (in particular, of at least about 150° C.; even more particularly, to a temperature of at least about 180° C.).
In detail, advantageously but not limitatively, the method also comprises a first detection step, at least partially subsequent to the second application step, during which at least one detection assembly 33 (advantageously of the type described above) detects the at least partially relief pattern formed on the surface 7 to be decorated during the second application step; and a synchronization step, at least partially simultaneous with the third application step, during which the second printing assembly 31 is operated (controlled), advantageously by a control assembly CU (of the type described above) based on what was detected in the aforementioned detection step so that the defined image is arranged with respect to the at least partially relief pattern so as to generate together with said pattern a defined decoration.
The method then comprises a firing step, during which the (in particular, each) slab of compacted ceramic powder KP having the defined decoration on the surface to be decorated is fired in a kiln 36 arranged at a third work station 37 downstream of the second decoration station 18 so as to obtain a finished ceramic product T.
More in detail, advantageously but not limitatively, the first detection step is subsequent to the drying step and at least partially preceding the third application step and comprises a position detection sub-step, during which a first position detector 43 (advantageously of the type described above) detects the position (i.e. the orientation) of the slab of compacted ceramic powder KP entering the second decoration station 14 with respect to the moving direction A, and a structure detection sub-step, during which a structure detection device 44 (advantageously of the type described above) detects the structure (in particular, the shape and/or the trend and/or the contours and/or the size) of the at least partially relief pattern formed on the surface 7 to be decorated during the first decoration step.
Alternatively or additionally, the first detection step also comprises at least one positioning sub-step, subsequent to the position detection sub-step, during which a first positioning/centring device (not shown and advantageously of the type described above) moves the (in particular, each) slab of compacted ceramic powder KP entering the second decorating station 14 so that the (in particular, each) slab of compacted ceramic powder KP assumes a given position (orientation) with respect to the moving direction A at the second decoration station 14 (in particular, so as to centre the slab of compacted ceramic powder KP with respect to the moving direction A).
Furthermore, according to some advantageous but non-limiting embodiments of the invention, the method also comprises a second detection step prior to the first application step, during which a second detection assembly 45 comprising a second position detector detects at least one position (i.e. orientation) of the slab of compacted ceramic powder KP entering the first decoration station 13 with respect to the moving direction A. In detail, advantageously but not limitatively, the second detection step also comprises a second positioning sub-step, during which a second positioning device (i.e., a centring device, similar to the previous one, and described above with reference to the decoration system 11) moves the (in particular, each) slab of compacted ceramic powder KP as it enters the first decoration station 13 so that the (in particular, each) slab of compacted ceramic powder KP assumes a given position (orientation) with respect to the moving direction A at the first decoration station 13 (in particular, so as to centre the/each slab of compacted ceramic powder KP with respect to the moving direction A).
According to some advantageous but non-limiting embodiments such as the one shown in
Alternatively or in addition to the foregoing, according to some embodiments, the method also comprises a final application step entirely similar to one between the first and third application steps described above and subsequent to the third application step, during which a fourth printing assembly 41, arranged downstream of the second printing assembly 31 along the given path P, applies a final layer 42, comprising (in particular, consisting of) a coating material, on the layer 32 to cover it, in particular on the given decoration formed on the surface 7 to be decorated to cover it.
According to some advantageous but non-limiting variants such as the one shown in
Advantageously, but not necessarily, the method is implemented by the decoration system 11 described above, so all the considerations set out above regarding possible operation variants of the decoration system 11 also apply to the method for decorating the base ceramic article BC. It is further understood that the steps of the method of the present invention (carried out according to any one of the above-described embodiments) can be repeated a finite number of times so as to achieve the desired decoration, in particular, it is possible to create an at least partially relief multilayer pattern on the surface 7 to be decorated, as well as it is possible to overlay several images on the at least partially relief pattern so as to generate the desired decoration.
The object of the present invention has several advantages if compared to the state of the art. These include the following ones.
By providing for the creation of the at least partially relief pattern in a decoration station 13 arranged upstream of the dryer 34, the present invention implies that at least the first printing assembly 15 and the depositing assembly 20 act to create such pattern on a “cold” slab (i.e., at room temperature) of compacted ceramic powder KP with considerable advantages on the final result. In fact, the forming the partially relief pattern on a “cold” surface (as opposed to the prior art which provides for decoration after drying) eliminates the risk of evaporation of part of the adhesive material 17 in contact with the hot surface 7 to be decorated which could compromise the final aesthetic appearance of the ceramic product T. Furthermore, the arrangement of the printing assembly 31 after the dryer 34, will allow the image (i.e. the chromatic decoration) to be realised on a partially relief pattern already dried and therefore more resistant and having the previously applied adhesive material 17 already crystallised (i.e. solidified), with obvious advantages in terms of ease of printing but above all in terms of quality of the final decoration obtained.
In addition, the arrangement of the first decoration station 13 upstream of the dryer 34 makes it possible to partially remove during the drying step a part of the harmful organic substances that make up the adhesive material 17, which reduces the waste substances produced during firing.
| Number | Date | Country | Kind |
|---|---|---|---|
| 102021000024380 | Sep 2021 | IT | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IB2022/058966 | 9/22/2022 | WO |
