EP4630248A1

EP4630248A1 - Continuous apparatus for decorating objects with sublimatic inks and continuous process using this apparatus

Info

Publication number: EP4630248A1
Application number: EP23773303.5A
Authority: EP
Inventors: Michele Bottaro
Original assignee: Isa Sleeve Srl
Current assignee: Isa Sleeve Srl
Priority date: 2022-12-07
Filing date: 2023-09-21
Publication date: 2025-10-15
Also published as: IT202200025167A1; WO2024120672A1

Abstract

The invention is directed to an apparatus for the continuous decoration of an object with sublimatic inks, which comprises the following elements: a carousel containing independent carousel groups; a carousel group handling system along a closed loop path, the closed path including a loading and unloading point; wherein each carousel group comprises: a base (12) capable of receiving a base group comprising an object to be decorated, a support and a sleeve, in which the object to be decorated is placed on the support and wrapped by the sleeve; a vacuum pump (15) connected by at least one tube (16) to the base (12); wherein the apparatus is provided with a system (17) for heating the base groups and capable of bringing the base groups to a temperature between 140°C and 250 °C and capable of subjecting the base groups to a profile of temperature with the travelling time; wherein the handling system is such that every single carousel group makes a complete tour along the closed path in a time comprised between 1 and 15 s; and wherein the base groups remain within the heating system for at least 50% of said time. The invention is also directed to a process of decorating an object with sublimatic inks, which process makes use of the above defined apparatus.

Description

Continuous apparatus for decorating objects with sublimatic inks and continuous process using this apparatus

Field of the invention

[0001]. The present invention is directed to a continuous apparatus for the decoration of objects with sublimatic inks and a continuous and automatic process using this apparatus. The apparatus according to the invention guarantees excellent printing quality together with high productivity as feeding, sublimation and unloading finished product are fully automatic and without the help of manpower and staff.

Background of the invention

[0002]. The decoration of objects with sublimatic inks is known in art since the late last century. EP 888 905, published in 1999, discloses a process to decorate an object with sublimatic inks; this process includes the steps of wrapping an object to be decorated in a sleeve containing a sublimation ink which presents on the sleeve the image to be transferred; heating the sleeve to obtain the heat shrinking of the same and cause the sublimation of the inks that are then transferred from the sleeve to the object. The process can include a preheating phase for the shrinking of the sleeve and/or a vacuum phase to evacuate the gases present between the sleeve and the object favouring the adherence of the sleeve to the object itself.

[0003]. WO 2021/260613 discloses a discontinuous process for the decoration of an object, in particular a bottle, with sublimatic inks according to EP 888 905, wherein a ventilated oven is used and equipped with a vacuum pump. However, discontinuous processes for the decoration of objects with sublimatic inks have limited industrial potential and only for large objects (shower trays or sanitary ware in general) where the value of the object justifies a high cost for decoration. In the case of smaller objects such as bottles and/or containers made of glass, ceramic, aluminium, or any material that can withstand the production conditions, the cost of the process and the low profitability in terms of pieces per hour, has until now blocked the industrial development of this technology.

[0004]. In fact, the processes currently used for the decoration of bottles use heat-shrink labels or painting, followed by screen printing or adhesive label. The use of shrink sleeves has been introduced to improve the aesthetics of products for sale and offer the advantage of versatility, as they can be adopted in a variety of product sectors. With these labels, which adapt to any shape, in fact, you can completely cover the products (bottles, bottles, etc.). The material with which they are made is transparent plastic, which ensures durability, colour rendering and speed of printing. However, the use of plastic is the factor that nowadays makes the use of this technology in the field of glass bottles quite critical, as it is necessary to separate the sleeve label from the bottle before recycling. [0005]. Another widely used technique is that of painting followed by screen printing or adhesive label. The cost of this technique is significantly higher than the cost of the technique that uses the sleeve, and again the presence of a plastic label requires a step of pre-treatment before recycling.

[0006]. The technique that presents the best aesthetic result is that of decoration with sublimatic inks. Moreover, this technique allows the recycling of bottles directly after use, without any pretreatment. The reason that has so far prevented a massive development of this technique is the cost of the process, which until now has been performed in discontinuous equipment, with low hourly productivity and consequently high costs of the single piece.

[0007]. W02007/129210 discloses an apparatus for decorating elongated objects such as section bars through sublimation of inks. The section bars are wrapped in a tubular enclosure having open ends made of a film of plastic bearing a sublimable decoration printed onto a side thereof facing the section bar. Vacuum is applied to the open ends of the section bars which are entered in a kiln wherein they are moved vertically until they rich the outlet from which they are extracted. The process makes use of a continuous kiln which, however, does not allow a proper control temperature inside the kiln, due to its large dimensions. Furthermore, it is not possible to subject to object to a temperature profile inside the kiln, since the temperature is a fixed value inside the kiln.

[0008]. WO2018/158687 discloses a system for transferring graphical representations on an object by sublimation, the system comprising: a first loading device configured to load on a work plane a support comprising at least one graphical representation to be transferred; a second loading device configured to load, in use, the object over said support on said work plane; a sublimation apparatus comprising a catenary and a plurality of pendulum components hooked to the catenary, each component comprising ends and jaws configured to cooperate with the work plane so that, by suction, said support wraps said object, is made to adhere to said object and is moved together with the object in an oven arranged for transferring the support graphical representation from the support to the object. The productivity of the system is however low, since the process is not a continuous process but a batch process and productivity are determined by the time spent by each object in the oven, which is run in batch.

[0009]. There is therefore a need for a new device for the continuous decoration of small objects with sublimatic inks, a device that allows a high production (of the order of 1200 pieces/ hour) while ensuring a high quality of printing.

Summary of the invention

[0010]. The present invention is directed to an apparatus for the continuous decoration of an object, which includes the following elements: a carousel containing independent carousel groups; a system for the movement of the carousel groups along a closed loop path, which closed path includes a loading point and a unloading point, preferably adjacent; wherein each carousel group includes: a base to receive a base group comprising an object to be decorated, a support and a sleeve, wherein the object to be decorated is placed on the support and wrapped by the sleeve; a vacuum pump connected with at least one tube to the base; where the apparatus includes a system for heating the base groups capable of bringing those base groups to a temperature between 140 and 250 °C and capable of subjecting the base groups to a profile of temperature in time, i.e capable of setting different temperatures in different zones of the apparatus, wherein the handling system is such as to make every single group ride a complete lap along the closed path in a time comprised between 1’ and 15’.

[0011]. The present invention is also directed to a process for the decoration of an object with sublimatic inks using an apparatus according to the invention. In a preferred embodiment, the process comprises the following steps: introducing a base group in the apparatus; optionally, subjecting the base group to a first heating step up to a temperature of 60-100°C; activating the vacuum pump; increasing the temperature of the base group up to 140-250°C; deactivating the vacuum pump; extracting the base from the apparatus.

Brief description of the drawings

[0012]. Figure 1 shows a top view of a first embodiment of a continuous device for the decoration of bottles with sublimatic inks.

[0013]. Figure 2 shows a front view of the apparatus of figure 1.

[0014]. Figure 3 shows a side view of the device of figure 1.

[0015]. Figure 4 shows a perspective view of the luminaire in figure 1.

[0016]. Figure 5 shows a detail seen from above of one of the two terminals and motorized elements of the apparatus of figure 1.

[0017]. Figure 6 shows a view in the section of figure 5.

[0018]. Figure 7 shows a front view of a carousel group (base + bell) before inserting a support on which there is a single bottle and a sleeve.

[0019]. Figure 8 shows a side view of the carousel group (base + bell) of Figure 7 after the insertion of a base group comprising a support on which there is a bottle and a sleeve.

[0020]. Figure 9 shows a side section of the device of figure 8 in open position.

[0021]. Figure 10 shows a side view of the device figure 8 in closed position and ready to start the heating phase.

[0022]. Figure 11 shows a side view of a base group to be used in a device according to the invention, consisting of a support on which there is an upside down bottle and a sleeve.

[0023]. Figure 12 is a sectional view of the base group of Figure 11. [0024]. Figure 13 is a top view of the base group of Figure 11.

[0025]. Figure 14 shows the top view of a second embodiment of a continuous device for the decoration of bottles with sublimatic inks in which the base groups on single row are heated in a tunnel.

[0026]. Figure 15 shows a frontal view of the apparatus of figure 14.

[0027]. Figure 16 shows a side view of the apparatus of figure 14.

[0028]. Figure 17 shows a perspective view of the apparatus of figure 14.

[0029]. Figure 18 shows a detail seen from above of one of the two terminal side elements of the apparatus of figure 14.

[0030]. Figure 19 shows a section view of Figure 18.

[0031]. Figure 20 shows a front view of the tunnel.

[0032]. Figure 21 shows a top view of the tunnel with interruption for loading and unloading.

[0033]. Figure 22 shows a perspective view of the tunnel.

[0034]. Figure 23 shows a section of the tunnel with the heating equipment on the side walls.

[0035]. Figure 24 shows the support base, complete with vacuum pump, base group and continuous rotation system of the base group, preferably present throughout the lap.

Descrizione dettagliata dell’invenzione

[0036]. Decoration of objects with sublimatic inks is widely described in the state of the art. In general, the object to be decorated is inserted into a sleeve of heat-shrink material on the inner surface of which there is a sublimatic ink. The sleeve therefore includes a base layer made of a shrink-resistant material, and a sublimatic ink deposited on the inner surface of the sheet. The ink can be deposited directly on the shrink material, or on the same material previously processed, with an insulating barrier effect treatment on the inner surface. The commonly used shrink material is chosen from polyethylene (PE), polypropylene (PP), polyethylene terephthalate (PET), polyvinyl chloride (PVC). The preferred materials are PP and PET. The thickness of the base film influences the costs and parameters of the process. The higher the heating temperature, the greater the thickness. On the other hand, the greater the thickness, the higher the cost of the sleeve and final disposal after use. Normally the film thickness is between 20 and 100 microns, preferably between 35 and 60 microns.

[0037]. In a discontinuous process according to the state of the art, on the object to be decorated a shrink sleeve is inserted and placed, so as to wrap it externally. The object to be decorated on which the sleeve was placed, is then placed in an oven. Optionally a preheating can be provided, to trigger a first shrinkage of the sleeve; this, in relation to the dimensional and shape characteristics of the object to be decorated. Once the shrinking is done, vacuum is applied, and the temperature rises until transfer of the ink from the sleeve to the object. [0038]. The present invention is directed to an apparatus for the continuous decoration of an object, which apparatus includes the following elements: a carousel containing carousel groups preferably in an amount comprised between 2 and 100; a group handling system along a closed loop path, whose route includes a loading point and a unloading point, preferably adjacent; each carousel group includes a base to receive a base group comprising an object to be decorated, a support and a sleeve, in which the single object to be decorated is placed on the single support and wrapped by the sleeve; a vacuum pump is connected with at least one tube at the base; wherein the apparatus includes a system for heating the individual carousel groups, which system is capable of bringing the base group to a temperature between 140 and 250 °C and capable of subjecting the base groups to a profile of temperature in time; and wherein the handling system is such as to make every single group cover a full lap along the closed path in a time comprised between 1’ and 15’. In a preferred embodiment, the apparatus completes a full lap in a time comprised from 1 ’ to 8’, more preferably from 4’ to 6’. It is important that the heating system not only is capable of heating the base group with an accurate temperature control, but that it also gives the possibility of subjecting the base group to a profile of temperature. For example, the temperature of the base group can be increased to a first value of 60- 100°C to allow the first heat shrinking of the sleeve and, only after a certain time, the temperature is increased to the final value of 140-250°C to sublimate the ink. Such a temperature control is not possible with the kiln of W02007/129210.

[0039]. In the process of the present invention, a first step is made to place the object to be decorated, such as, for example, a bottle, on a support, operation that can be done manually or automatically. This support is made in such a way as to allow the placement of the sleeve later. The set consisting of the support, the object to be decorated and the sleeve will be defined as the base group.

[0040]. Once this basic unit including the holder, the object to be decorated and the sleeve has been prepared, it is transferred to the continuous decoration unit. This transfer can take place either manually, that is through the presence of an operator who takes the base group and places it on the base, or through a screw + star system, also continuous. In the latter case, the feeding takes place through a spacer screw at the entrance to a star that accompanies the base group to the carousel group. The preparation procedure is exactly the same whether it is a carousel with bells (Figure 1-10) or a carousel with a tunnel as a continuous oven (Figure 14-24).

[0041]. The base, once in the apparatus, is immediately subjected to a heating, that can either be heating to the sublimation temperature, or a first heating to a temperature suitable to shrink the sleeve. Such a temperature is usually comprised between 60 and 100 °C. After the shrinking temperature is achieved, the vacuum pump is activated, to evacuate the gasses from the sleeve; the temperature is then raised to the sublimation temperature, i.e. 140°C-250°C, preferably 180°C-250°C.

[0042]. Figure 1 shows a view from above of a device according to the invention in which the objects to be decorated are bottles and in which heating takes place through a bell present in each carousel group. Figures 2, 3 and 4 show the apparatus of Figure 1 in different views to illustrate in more details the operation of the apparatus. The carousel group with bells in the feeding position, has the insulated bell 8 in high position, thanks to the movement of slide 13 connected to lifting cam 9. The movement and sliding of the carousel clockwise take place on an upper slide 7 with sliding elements 14 and on a lower slide 7 with sliding elements 11.

[0043]. Bottles can be made of glass, aluminium, ceramic, steel or any other material stable at working temperature. The working temperature is between 140-250°C. This temperature depends on the characteristics of the sublimation ink. In fact, it is essential that the temperature reached during the heating phase of the base group is higher than the sublimation temperature of the ink. The temperature affects the time needed to complete the decoration, in the sense that an increase in temperature reduces the time needed to complete the decoration.

[0044]. Within the invention, the number of carousel groups present in the apparatus according to the invention depends on various interrelated parameters. A first parameter is the speed of movement of the carousel groups inside the carousel itself. In principle, the higher the speed, the higher the hourly productivity. For example, if the carousel groups move inside the carousel at a speed of 10 cm/s, if the time needed to complete the decoration is 3', that is 180 s, the length of the path of a single carousel group from the start of heating to the end of the process is 18 m. Considering a distance between a group and the adjacent group of 25 cm, we come to a number of carousel groups between the beginning and the end of the heating of 72 carousel groups. From figure 1 we can see how, in the specific case, are necessary 6 groups carousel to realize the opening and the closing of the bell, bringing the total number of groups carousel to 78. A travel speed of 10 cm/s with a centre distance of 25 cm also means an hourly productivity of 1 piece every 2.5 s, which means an hourly productivity of 1440 pieces/hour. Of course, varying the size of the pieces and the time needed to complete the decoration will vary the total number of carousel groups.

[0045]. Thus, at a design stage, it will be essential to start from the required production of the apparatus that derives from commercial considerations, and from here, fixed the decoration time, calculate the number of required carousel groups under the fixed conditions. It is evident that the apparatus of this invention can be used both for very high productions of the order of 1000 pieces/hour or more, and for small productions of the order of 50-200 pieces per hour, where the speed of movement of the carousel is even less than 1 cm/s and the number of groups present is between 2 and 10. Even in this small scale, the device according to the invention has a considerable advantage over the state-of-the-art batch furnaces that are able to produce 10-30 pieces/hour.

[0046]. Figure 5 shows a detail seen from the top of one of the two terminal side elements. The terminal side element represents the drive system 3 and drive wheel 5 of the whole set of bells. All bell groups are connected to each other via connecting rods 4 to create a chained and closed system. [0047]. Figure 6 shows a frontal view of one of the two terminal side elements in which the supporting structure at ground 10 with fixed supports 7,9 for all the guide and sliding units of the bell groups 8. Power transmission to the individual bell groups 8 takes place via fixed electrical conductors and sliding transmitters 6.

[0048]. Figure 7 is a frontal view of a carousel group 1. The carousel group consists of a base on which the base groups defined above are placed. Above, the carousel group 1 includes a bell 8 sliding vertically following a path of a cam 9 suitably shaped in the loading and unloading areas.

[0049]. Figure 8 is a side view of the carousel group of Figure 7 in which a base group is present. There are defined the upper travel guides 14, lower travel guides 11, the lifting cam 9 of the bell, the vacuum pump 15 positioned under the base and the upper suction tube 19 inserted in the upper part of the bell.

[0050]. Figure 9 is a cross-section view of the carousel group of Figure 8. We see how the lower intake tube 16 is connected to the support of the base group, while the upper tube 19 has a cannula 20 that, once the bell 8 is lowered, is positioned in the concavity of the bottle, as shown in figure 10. Once the vacuum is activated, cannula 20 creates a depression in the concavity of the bottle. This allows a good adherence of the sleeve to the concave part of the bottle. Figures 9 and 10 also show the resistors 17 in the bell, the outer casing 18 and the lid 21. On the left side of the figure there are the lower travel guide 11, the support plate of the bottle 12, the lifting guide of the bell 13 and the upper travel guide 14.

[0051]. Figure 11 is a side view of the printing group present in Figure 8. It can be noted that the bottle is inserted in a support, as best highlighted in Figure 12, showing the support base 22, the bottom centering round 24 and a top centering round 26 that hold the bottle 27 in the correct position. In addition, Figure 12 highlights the outer ring 23 that holds the sleeve 25 in the correct position.

[0052]. The apparatus according to the invention represented in Figures 1-10 provides for the insertion of the base group in a carousel group in an entry position, the subsequent closure of the bell and the activation of the resistances 17 present in the bell itself in order to heat the internal volume of the bell. The resistances have the task of heating the base group inside the bell up to the sublimation temperature of the ink and then maintain constant the temperature inside the bell. The temperatures in the individual bells are controlled with multiple temperature probes and in multiple points. The relatively small size of the bell allows for an accurate temperature control inside the bell, and results in an improved quality of the printing job when compared with a situation where the temperature control is less accurate. Another important point is the energy saving, for this reason each bell is preferably suitably insulated with high insulating power materials and thus reducing the continuous operation of the resistances. The vacuum pump 15 is preferably activated a few seconds after the activation of the resistors. In fact, preferably, the vacuum pump is activated after the shrinking of the sleeve has taken place, inside the closed bell. If not necessary, the vacuum pump can also be excluded from operation or even operated at any time depending on the chosen sublimation cycle. During the movement of the carousel group in the closed path, the base group heats up to the sublimation temperature of the ink. The speed of movement of the carousel and the number of carousel groups present are such as to ensure the completion of the decoration in a complete lap of the carousel. Near the exit station the resistances and the vacuum pump are deactivated, the bell is raised, and the base group is taken from the single bell group on which it was placed. In the loading station, a new base group to be decorated is automatically inserted.

[0053]. A second embodiment is shown in Figures 14-24, in which the heating medium of the base groups is represented by a heating tunnel. The base group is placed on a single carousel group and then the group moves inside a fixed heating tunnel. After a few seconds after entering the tunnel, once the heat shrinking temperature has been reached, the vacuum pump is activated. Shortly before exiting the tunnel, the vacuum pump is switched off and once out of the tunnel, the base unit is removed from the carousel.

[0054]. Both the bell and the tunnel allow to set different temperatures in different zones of the apparatus. Thus, both embodiments represent an improvement over the prior art in that they not only are suitable for a more accurate control of the temperature of the base group, but also are suitable for setting different temperatures during the printing lap.

[0055]. In order to achieve a high productivity of the apparatus, it is important that the object to be decorated, and thus the base group, remains into the heating system as much as possible. When using the apparatus comprising heating bells, the base group is not inside the bell only during closing of the bell at the beginning of the lap and opening of the bell at the end of the lap. When using a heating tunnel, this time is further reduced since the base group enters the tunnel immediately after being charged on the apparatus and exits the tunnel just before being discharged from the apparatus. In general, the base group will be in the heating system (i.e. inside the tunnel or with the bell in closed position) for at least 50% of the lap time, preferably at least 75% of the lap time, even more preferably at least 90% of the lap time. [0056]. Figure 14 shows a top view of an apparatus according to the invention in which the objects to be decorated are bottles and in which heating takes place through the passage of the carousel groups 28 in a heated tunnel. Figures 15, 16 and 17 show the apparatus of Figure 14 in different views to illustrate in more details the operation of the apparatus. Carousel groups 28 are fed through an auger + star system 29.

[0057]. Figure 18 shows a detail seen from the top of one of the two terminal side elements. The terminal side element represents the drive system 30 and the driving wheel 32 of the entire carousel. All carousel groups are connected to each other by connecting rods 31 to create a chained and closed system.

[0058]. Figure 19 shows a frontal view of one of the two terminal side elements in which the insulated tunnel 33 is highlighted, the frame of the carousel 34, the guide 35 for the rotation of the bottle plate, the support 36 of the guide 35, the armoured bar 37 and the guide 38 of translation of the carousel group 28.

[0059]. Figures 20, 21 and 22 represent the insulated tunnel in different views.

[0060]. Figure 23 is a cross-section view of the tunnel in which the outer casing 39, the resistance 40, the insulation 41 and the opening door 42 are shown.

[0061]. Figure 24 represents a sectional view of a carousel group comprising a base group. On the left side, the lower travel guide 43 and upper travel guide 44 are highlighted. In the lower right the pump 45 connected to the tube 46 inserted in the lower part of the base formed by the wheel 47 of rotation of the bottle, above which is the bearing 48 and the support plate 49.

[0062]. Both embodiments guarantee an effective removal of air and gases formed by the sublimation process, contributing in an important way to the achievement of a very high quality printing process. This result is achieved in both cases by the presence in each base group of a vacuum pump. Depending on the case, it will be possible to connect the vacuum pump with one or more tubes that remove the gases from the lower and/or upper part of the object to be decorated. The use of two tubes allows to have a high quality printing of bottles wherein the decoration comes close to the concave part of the bottle.

Claims

1. An apparatus for the continuous decoration of an object with sublimatic inks, which apparatus comprises the following elements: a. a carousel containing independent carousel groups (1, 28); b. a carousel group handling system along a closed loop path, the closed path including a loading point and an unloading point; wherein each carousel group comprises: i) a base (12,49) capable of receiving a base group, which base group comprises an object to be decorated, a support and a sleeve, in which the object to be decorated is placed on the support and wrapped by the sleeve; ii) a vacuum pump (15, 45) connected by at least one tube (16, 46) to the base (12, 49); wherein the apparatus is provided with a system for heating the base groups and capable of bringing the base groups to a temperature between 140°C and 250 °C and capable of subjecting the base groups to a profile of temperature in time; wherein the handling system is such that every single carousel group (1, 28) makes a complete tour along the closed path in a time comprised between 1’ and 15’; and wherein the base groups remain within the heating system for at least 50% of the lap time.

2. The apparatus according to claim 1, wherein the object to be decorated is a bottle placed on the support in a vertical position with the neck down.

3. The apparatus according to any of claims 1 or 2, wherein the number of carousel groups is between 2 and 100.

4. The apparatus according to claim 3, wherein the number of carousel groups is between 10 and 80.

5. The apparatus according to any of claims 1 to 4 wherein the time necessary for a carousel group (1, 28) to complete a tour is between 4'and 6'.

6. The apparatus according to any of claims 1 to 5, wherein the base groups are within the heating system for at least 75% of the lap time.

7. The apparatus according to any of claims 1 to 6, wherein the loading and unloading points are adjacent.

8. The apparatus according to any of claims 1 to 7, wherein the vacuum pump (15) is connected with two tubes (16, 19).

9. The apparatus of claim 8, wherein the first tube (16) is connected to the bottom centering round (24), and the second tube (19) is connected to a cannula (20) positioned within the lid (21) and positioned in such a manner that, when the bell is closed, canula (20) is positioned within the concavity of the bottle.

10. The apparatus according to any of claims 1 to 9, wherein the heating of each base group takes place through a bell (8) suitable to fully contain the object to be decorated, equipped with heating means and capable of closing the volume between the base (12) and the bell (8), once the bell (8) is juxtaposed to the base (12).

11. The apparatus according to any of claims 1 to 5, wherein the heating of the base groups takes place through a tunnel through which the independent base groups pass during the movement in the closed path.

12. A process of decorating an object with sublimatic inks, which process makes use of the apparatus of any of claims 1 to 11.

13. The process according to claim 12, wherein the temperature of the base groups during heating reaches a value comprised between 180 and 250°C.

14. The process according to any of claims 12 or 13, comprising the following steps: i. introducing a base group in the apparatus according to claims 1-10; ii. activating the vacuum pump; iii. increasing the temperature of the base group up to 180-250°C; iv. deactivating the vacuum pump; v. extracting the base from the apparatus.

15. The process according to claim 14, further comprising after step i. the step: subjecting the base group to a first heating step up to a temperature of 60-100°C.