The Prior Art includes decorating apparatuses that apply a decorating path to an object to be decorated, said decorating apparatuses working according to a preset printing technique.

In particular, EP 0677364 discloses an intaglio type decorating machine, provided with at least one printing unit consisting of a decorating roller on the surface of which a plurality of cavities, arranged according to a pre-established pattern, is obtained. The cavities are filled with glaze that is transferred to the tile to be decorated during rotation of the roller around a respective axis.

In the case that, as nearly always it occurs, the tile is desired to be decorated with a pattern comprising more than a single colour, a plurality of printing units must be provided on the decorating machine, each printing unit being provided with a respective decorating roller, each decorating roller being etched according to its own pattern and designed for applying a different colour. The desired end pattern can be obtained by superimposing the colours and the patterns applied by each decorating roller.

A drawback of the decorating machines disclosed in EP 0677364 is connected to their complexity, mainly arising when the patterns to be applied on the surface of the tiles comprise more colours, for example two different colours. In that case, in fact, two printing units must be provided, each provided with respective auxiliary devices, such as supporting and driving devices.

The decorating machine consists then of an high number of elements, that remarkably complicates its design,

construction, assembly and maintenance, consequently causing high installing and operating costs.

In addition, since the printing units are sequentially arranged along a production line developing in horizontal direction, the decorating machines comprising multiple printing units have a remarkable length, that can cause encumbrance troubles in the event that the decorating machines must be inserted in a pre-existing layout or in a plant of reduced size.

A further drawback of the decorating machines of the previously disclosed type lies in that, in view of obtaining satisfying results from an aesthetical point of view, it is necessary that the pattern applied by a specific decorating roller is perfectly aligned with the pattern applied by the remaining decorating rollers. In other words, the position of any decorating roller must be perfectly in phase with the position of the remaining decorating rollers, in such a way that undesired overlapping between different colours does not occur.

In order to ensure a perfect in phase rotation between the decorating rollers, frequent adjusting operations must be performed, that involves stopping the production line and consequent loss of production. In addition, whenever errors occur in the mutual positioning of the patterns of different colours, the tiles carrying the faulty patterns must be discarded, or a lower decorating quality must be accepted.

This event arises quite frequently, since the vibrations present on the machine, the shocks, the excessive stresses and the normal wear can easily alter the previously performed regulations.

A purpose of the invention is to improve the apparatuses and the methods for decorating objects, particularly the objects provided with a flat surface.

A further purpose of the invention is to provide apparatuses for decorating objects involving a lower economic expenditure than the known apparatuses, regarding in particular the installing and maintaining operations.

A further purpose of the invention is to provide apparatuses and methods for decorating objects involving a reduction of the rejected items and a lower error possibility during the decorating phase.

A further purpose of the invention is to provide apparatuses for decorating objects that can be easily arranged in pre- existing layout or in plants of reduced size, without giving rise to insurmountable problems of encumbrance.

A further purpose of the invention is to enable a multi-colour decoration to be easily applied to objects such as ceramic supports.

In a first aspect of the invention, an apparatus is provided for decorating objects, particularly provided with a flat surface, comprising first applying means and second applying means suitable for applying to transferring means respectively first decorating means and second decorating means, characterized in that, said first applying means and said second applying means are arranged in a single printing unit, so as to apply simultaneously said first decorating means and said second decorating means.

Owing to this aspect of the invention, the decorating apparatuses of the prior art can be remarkably improved, and in particular their productivity can be raised, since the first applying means and the second applying means enable to simultaneously apply first decorating means and second decorating means, comprising for example a first colour and a second colour, so as to form a complex ornamental pattern.

That enables to simplify the decorating apparatuses, by virtually halving the number of printing units needed for transferring on an object like a tile a pre-established

pattern, that turns out as a remarkable reduction of the installing and maintaining costs of the apparatus.

In addition, the lower number of required printing units enables to reduce the encumbrances of the decorating apparatus according to this aspect of the invention, so that such apparatus can be easily arranged also in small plants or in pre-existing layouts.

In a preferred version, the transferring means comprises first transferring means suitable for transferring the first decorating means on said objects according to a first printing technique, and second transferring means suitable for transferring the second decorating means according to a second printing technique.

That enables to couple in the same printing unit two different printing techniques, so that the advantages offered by these two techniques can be combined in order to obtain high quality aesthetical results.

In a further preferred version, the first transferring means comprises cavity means suitable for receiving said first decorating means and for transferring said first decorating means on said objects according to an intaglio printing principle.

The second transferring means comprises protruding means suitable for receiving said second decorating means and for transferring said second decorating means on said objects according to a letterpress printing principle.

Advantageously, the first transferring means and the second transferring means are associated with mutually complementary surfaces in said printing unit.

Since the mutual position of the first transferring means and the second transferring means is fixed, any mutual displacement of the first transferring means and the second transferring means is prevented. That enables the apparatus according to the first aspect of the invention to totally

remove the positioning problems between the portion of ornamental pattern applied by the first transferring means and the further portion of ornamental pattern applied by the second transferring means.

In an advantageous version, the transferring means comprises hollow means suitable for receiving in succession the first decorating means and the second decorating means.

As the first decorating means and the second decorating means are applied to the same hollow means, besides the above mentioned advantages about the simplified construction and maintenance of the apparatus, aesthetically pleasant effects can also be obtained, since the first decorating means and the second decorating means arrange themselves into the hollow means in a non-repetitive manner, adopting different configurations at any one time. Thus, any decorated object differs from the remaining ones, which gives the impression that a different pattern has been manually applied on any object and gives the decorated objects a remarkable value.

This effect is particularly appreciated when the decorating pattern comprises veining imitating marble or natural stones, since this effect enables to reproduce the non-repetitive and always different aspect of the elements present in nature.

In a second aspect of the invention, a method is provided for decorating objects, particularly provided with a flat surface, comprising applying first decorating means and further applying second decorating means to transferring means, characterized in that, said applying and said further applying occur simultaneously in a single printing unit.

Owing to this aspect of the invention, the known methods can be simplified and made more productive, since it is possible to apply simultaneously first decorating means and second decorating means, comprising for example a glaze with a first colour and a further glaze with a second colour, both suitable for decorating a ceramic tile. Consequently, the decorating

times can be almost halved, that involves very significant saving from the point of view of the profitability of the productive process.

In an advantageous version, the method further comprises transferring the first decorating means from first transferring means of the transferring means to said objects according to a first printing technique, and further transferring the second decorating means from second transferring means of the transferring means to said objects according to a second printing technique.

That enables to couple the advantages of two different printing techniques, so as to optimize the aesthetical result obtained by means of the method disclosed in this second aspect of the invention.

Advantageously, said transferring comprises filling cavity means with said first decorating means and removing the first decorating means from said cavity means.

Still advantageously, said further transferring comprises covering protruding means with said second decorating means and moving the second decorating means from said protruding means to said objects.

In an advantageous version, said applying and said further applying involve rotating a single decorating roller, with which said single printing unit is provided.

Since during said rotating any relative movement between the first transferring means and the second transferring means is prevented, the problems of incorrect positioning between the portion of ornamental pattern applied by the first transferring means and the portion of ornamental pattern applied by the second transferring means result totally removed.

In a further advantageous version, said applying and said further applying comprise depositing in succession the first

decorating means and the second decorating means into hollow means of said transferring means.

Since the hollow means is filled with the first decorating means and with the second decorating means in a non-repetitive manner, different gradations in colour, overlays and shading can be obtained on any decorated object, which represents an enjoying reason for the user, particularly for certain kinds of products, as the user has the impression that its product is different from any other product and specially conceived for himself.

The invention can be better understood and carried out with reference to the enclosed drawings, that illustrate some exemplifying and not restrictive embodiments thereof, wherein : Figure 1 is a sketched, front view of an apparatus according to the invention ; Figure 2 is a sketched, front and enlarged view of a printing unit of the apparatus of Figure 1 ; Figure 3 is a sketched and enlarged cross section of a decorating roller making part of the apparatus according to the invention ; Figure 4 is a sketched, front view of a version of the apparatus according to the invention, suitable for decorating flexible objects ; Figure 5 is a sketched, front view of an alternative version of the apparatus according to the invention ; Figure 6 is a sketched and enlarged front view of a printing unit of the apparatus of Figure 5.

With reference to Figure 1, an apparatus 1 is shown for decorating objects, particularly objects provided with a flat surface, for example ceramic tiles 2, transported by a conveyor 3 along an advancing direction F, the conveyor 3 comprising for example a belt 4, wound around a pair of pulleys 5. The ceramic tiles 2 are decorated by a printing unit 6, comprising a decorating roller 7 rotatable around its

own axis Z and enclosed by an external surface 8 that during rotation lies in contact with a surface 9 to be decorated of the ceramic tiles 2.

The structure of the decorating roller 7 is shown in more details in Figure 3, from which it can be inferred that the decorating roller 7 is provided with an external tubular element 14 whereon transferring means is obtained in order to transfer an ornamental pattern to the tile 2. The transferring means is provided with first transferring means, comprising a plurality of cavities 19, and second transferring means, comprising a plurality of protruding elements 15.

The cavities 19 and the protruding elements 15 are not arranged in casual manner on the surface 8 of the decorating roller 7, but according to the ornamental pattern that is desired to be printed on the tile 2.

The tubular element 14 is made preferably of easily yielding and deformable material, for example silicone, polyurethane, rubber or other elastomeric material, and is mounted on a base structure 16, comprising a supporting element 17 made of a material provided with high stiffness, such as a metal or a rigid plastic.

The supporting element 17 has preferably the shape of a hollow cylinder, so as to reduce the rotating inertia of the printing roller 7 and make easier the manipulation thereof. The base structure 16 can also comprise, externally to the supporting element 17, one or more intermediate layers 18, made preferably of yielding and easily deformable material, such as silicone, polyurethane, rubber or other elastomeric material, in case in form of foam. The intermediate layer 18 has the function of giving the necessary flexibility to the decorating roller 7 for adapting itself to the surface irregularities of the ceramic tiles 2 to be decorated, without producing any damage thereof.

As highlighted in Figures 1 and 2, during rotation around the Z axis, first decorating means are supplied on the decorating roller 7, by means of first applying means provided with a feeding device (not shown). The first decorating means comprises a first ceramic glaze 11, that arranges itself inside the cavities 19 obtained on the external surface 8 of the decorating roller 7. The applying means further comprises a doctor blade 20, that provides to scrape the exceeding glaze from the protruding elements 15, ensuring that no trace of the first ceramic glaze 11 received by the cavities 19 remains on the surface of said elements 15.

The position of the doctor blade 20 can be variously adjusted according to the producing requirements, for example according to the type of glaze and the chemical, physical and rheological properties thereof. In particular, it is possible to adjust the inclination angle of the doctor blade 20 with respect to the surface 8 of the decorating roller 7, or the pressure exerted by the doctor blade 20 against said surface 8. This last adjustment is particularly important because, in order that the doctor blade 20 is able to remove any trace of the first glaze 11 from the protruding elements 15, it is necessary that said doctor blade 20 is pressed against the surface 8 of the decorating roller 7 with a sufficiently high pressure.

The doctor blade 20 can further be provided with an alternating translation movement along the direction of the longitudinal axis of the decorating roller 7.

Once the cavities 19 of the decorating roller 7 have been filled with the first ceramic glaze 11 and the protruding elements 15 have been cleaned by the doctor blade 20, the decorating roller 7, rotating around the Z axis, interacts with second applying means provided with a distributing roller 10, arranged for distributing on said printing roller 7 second decorating means, comprising a second ceramic glaze 11',

having for example a different colour with respect to the first ceramic glaze 11.

A supplying device, not shown, supplies the second ceramic glaze 11'on the distributing roller 10, that is provided, on its external surface 13, with further cavities, not shown, obtained for example by laser-beam etching. Said further cavities are arranged for receiving at their interior the second ceramic glaze 11'and for transferring said second ceramic glaze 11'to the decorating roller 7. Preferably, the further cavities are uniformly distributed on the entire external surface 13 of the decorating roller 10, which external surface 13 can consist of rigid material, for example metal, or easily deformable material, for example silicone.

A further doctor blade 12, arranged on the external surface of the distributing roller 10, provide to scrape the exceeding second ceramic glaze 11'from said external surface 13, thus ensuring a uniform filling of the said further cavities.

By coming into contact with the decorating roller 7, the distributing roller 10 transfers the second ceramic glaze 11' from its external surface 13 to the external surface 8 of the decorating roller 7. However, the second ceramic glaze 11'is not uniformly distributed on the entire external surface 8 of the decorating roller 7, but only at the protruding elements 15, forming raised portions capable of interacting with the distributing roller 10.

Since in fact the cavities 19 are in a more internal position with respect to the protruding elements 15, said cavities 19 do not come in contact with the external surface 13 of the distributing roller 10 and therefore do not receive the second ceramic glaze 11', but only the first ceramic glaze 11 that, on the other hand, does not occupy the protruding elements 15, from the surface of which said ceramic glaze 11 was previously removed by the doctor blade 20.

Thus, the first ceramic glaze 11 and the second ceramic glaze 11', by depositing themselves respectively into the cavities 19 and over the protruding elements 15, define complementary portions of the pattern, imprinted on the decorating roller 7, that is desired to be transferred on the tile 2.

When, during the rotation around the Z axis, the decorating roller 7 interacts with the surface to be decorated 9 of the tile 2, the first ceramic glaze 11 and the second ceramic glaze 11'are simultaneously transferred on the same tile, without any possibility of mutual displacements or undesired overlays.

In a version not shown, after the first ceramic glaze 11 and the second ceramic glaze 11'have been transferred on the tile 2 to be decorated, the surface 8 of the decorating roller 7 can be cleaned by cleaning means, comprising for example a third doctor blade or a cleaning roller, scraped at its turn by a respective doctor blade. In this manner there is the assurance of removing any possible surplus of glaze before the decorating roller 7 is covered again by glaze for decorating a new ceramic tile 2.

In Figure 4 an alternative version is shown of the decorating apparatus according to the invention, particularly suitable for decorating objects of small thickness, that result therefore flexible, such as textiles, plastic films, pellicles and generally sheet material 21, unwound from a first, unprinted reel 22. A plurality of rollers 23 define a path for the sheet material 21, along which said material comes into contact with the external surface 8 of the decorating roller 7 and, according to totally analogous ways as previously described for the ceramic tiles, said sheet material is decorated on one side 24 by the decorating roller 7, that applies thereto a first decorating substance 26 and a second decorating substance 26'according to an ornamental pattern.

The sheet material 21 is then rewound on a second reel 25 of printed material.

When more than two colours are desired to be applied on the objects to be decorated, more than one printing unit 6 can be in succession arranged along the advancing direction of that objects, each of said printing units 6 being arranged for applying for example two different colours, so as to transfer to said objects the desired ornamental pattern, as complicate as it may be.

Figure 5 shows an alternative version of the apparatus 1, particularly suitable for decorating objects, such as ceramic tiles 2, with an irregular and non-repetitive pattern, for example veining imitating marble or natural stone.

In the version of Figure 5, the decorating roller 7, that may have a structure of the type indicated in Figure 3, is externally provided with transferring means comprising a plurality of hollows 19'and, during its rotation around the Z axis, said decorating roller 7 interacts initially with first applying means, comprising a supplying device (not shown) and a doctor blade 20. The supplying device distributes on the surface 8 of the decorating roller 7 first decorating means, comprising for example a first ceramic glaze 11, that the doctor blade 20 provides to distribute into the hollows 19', while keeping clean at the same time the separating regions between adjacent hollows 19'.

The doctor blade 20, that can be variously adjusted according to what previously explained, is hold preferably strongly pressed against the surface 8 of the decorating roller 7, so that the first ceramic glaze 11 does not totally fill the hollows 19', but only partially.

Filling of the hollows 19'is then completed by second applying means, comprising a supplying device, not shown, arranged for supplying a second ceramic glaze 11', and further comprising a second doctor blade 27. Owing to the second

doctor blade 27, the separating regions between the adjacent hollows 19'are scraped so as to remove therefrom the second ceramic glaze 11', that arranges itself into the hollows 19', inside which said second ceramic glaze 11'superimposes itself on the first ceramic glaze 11.

After interacting with the second applying means, each of the hollows 19'contains therefore both the first ceramic glaze 11 and the second ceramic glaze 11', both of which can mix together and adopt multiple different configurations.

According to the manner in which the first ceramic glaze 11 and the second ceramic glaze 11'arrange themselves into the hollows 19'and how much said ceramic glazes 11 and 11'mix and superpose themselves, different aesthetical effects can be obtained on the tiles 2. Thus, even though always the same pattern is transferred on the tiles 2, which pattern is defined by the arrangement of the hollows 19'on the external surface 8 of the decorating roller 7, different contours, shades and gradations in colour are obtained for each tile 2, so as to give the user the feeling of being in presence of natural products and not of products industrially manufactured on a mass production base.