In-mould labelling

Abstract

A method for in-mould labelling, wherein the method comprises loading multiple planar sheets of IML label material into a magazine, wherein each sheet comprises one or more pre-printed in-mould labels held in remaining material of the sheet. A sheet is retrieved from the magazine and the one or more labels are removed out of the sheet. The remaining material of the sheet is waste material. The one or more labels are inserted into a corresponding number of cavities in a mould of a moulding device. The waste material is discarded.

Description

[0001] IN-MOULD LABELLING

[0002] The present invention relates to the field of in-mould labelling, wherein an in-mould label, also referred to as IML label, is placed in a cavity of a mould of a plastic products moulding device for the production of plastic products.

[0003] In-mould labelling is a well-known technique applied in the production of plastic products using a moulding device, e.g. an injection moulding device. In practice, a label is placed in each cavity of a first mould member of the mould whilst the mould is open. A second mould member is then pressed against the first mould member to close the mould. Often, the first mould member has multiple cavities in order to produce multiple products per cycle. In a moulding phase the IML label becomes integral with moulded plastic product, e.g. as molten plastic material is injected into the mould. After termination of the moulding phase the mould is opened and the moulded product or products is / are removed.

[0004] In the field several different approaches of providing IML labels to the moulding device are known.

[0005] For example, in EP3127675 it is disclosed to arrange stacks of printed IML labels in a set of magazines. A group of labels is then removed from the set of magazines by a first label transfer device. Herein, the still planar labels are arranged in a common vertical plane. This first label transfer unit moves the group of labels to a transfer position where the labels are each transferred onto a false core member of a second label transfer device. The second label transfer device then brings the labels to the respective cavities of a first mould member of an injection moulding device and the labels are then each placed into the respective cavity.

[0006] In EP3180250 use is made of a roll of label material, wherein printed IML labels have been partially stamped out so as to remain connected to the roll via so-called micro connections. A roll of such label material is handled by an unrolling device so that a section of the roll is temporarily exposed as a planar web section. A label transfer device operates to separate a group of labels from the planar web section. Herein the micro connections are broken. The label transfer device then delivers the group of labels to a second label transfer device which then brings the labels into the respective cavities of a first mould member of a plastic products moulding device. The unrolling device can be equipped with a collecting device in order to handle the residual roll material, also called waste, either by rolling it up onto a roll, to mill it, or to compress the waste material.

[0007] The above mentioned methods of providing IML labels in the course of moulding plastic products result in limitations. For example, limitations concern the printing of the labels, the label shape, and / or the label size. Also issues arise concerning the label handling, e.g. the behaviour of the labels during handling, and / or the capacity of the known approaches, e.g. the number of labels that can be handled per cycle at (very) short cycle times. Also, the known approaches may not be satisfactory in view of the amount of waste material and / or the handling of the waste material.

[0008] The present invention aims to reduce or overcome one or more of the above-mentioned drawbacks of the prior art approaches.

[0009] The present invention provides a method according to claim 1.

[0010] The method for in-mould labelling comprises the steps of:

[0011] - loading multiple planar sheets of IML label material, for example a stack of sheets, into a magazine, wherein each sheet has one or more pre-printed in-mould labels held in remaining material of the sheet,

[0012] - retrieving a sheet from the magazine,

[0013] - removing the one or more labels out of the sheet, wherein the remaining material of the sheet is waste material,

[0014] - inserting the one or more labels into a corresponding number of cavities in a mould of a moulding device,

[0015] - discarding the waste material.

[0016] Providing pre-printed IML labels on planar sheets of IML label material has several advantages over the prior art approaches. For example, compared to the supply of a roll of IML label material with pre-printed IML labels, it is considered advantageous that the labels are not stored while in a curved position. It is observed that even with the thin IML label material used nowadays, labels that have been part of a roll can be difficult to handle, e.g. at a high pace, e.g. due to a memory effect so that some of the curvature remains in the material.

[0017] Providing pre-printed IML labels on planar sheets of IML label material also has benefits over providing separate printed IML labels to the moulding facility. For example, handling, shipping, and / or storage of separate labels is more complex than doing so whilst the label(s) are still held in the planar sheet that is loaded in the magazine. For example, individual labels may easily wrinkle, fold, and / or stick together, and / or tend to shift, for example when being loaded into a magazine and / or upon removal from the magazine. This is of particular relevance when multiple labels are to be placed into mould cavities per cycle at high speed.

[0018] Additionally, printing of the IML labels on sheets of label material can be done highly effectively, e.g. on AO format sheets. It is envisaged, in embodiments, in view of transportation, handling, and / or storage, that an AO size printed IML label sheet with multiple labels thereon, is cut into smaller sized sheets, each containing one or more IML labels, for use in the inventive method. Preferably, the cutting up of the initially printed IML sheet into multiple sheets of a smaller size is done at the printing facility, prior to shipment to the moulding facility. These sheets are then to be loaded into a magazine for performing the inventive method.

[0019] For example, the sheets which are loaded into the magazine for performing the inventive method are of the A2, A3, A4, or A5 size. In practical embodiments, A3 and A4 are preferred sizes for the sheets.

[0020] The inventive approach is also advantageous when the one or more labels in a sheet each have a closed outer contour as well as at least one closed inner contour extending about a portion of the remaining material of the sheet. Herein, the closed inner contour defines a cutout of the label once removed out of the sheet. For example, the label is ring shaped and has a single cut-out, e.g. a central cut-out. Ring shaped IML labels are known, however they are made as discrete IML labels that are then shipped, stored, and handled in this format. This creates the above mentioned problems. As the invention keeps the ring shaped labels as part of the planar sheet until their removal in the IML process, these problems are avoided, or at least reduced.

[0021] The inventive approach is also advantageous for IML labels having a C-shaped, U-shaped, or V-shaped form. Such forms of labels are difficult to handle as separate labels, e.g. during shipping, storing, loading into a magazine. As they are part of a planar sheet during these phases in the context of the inventive approach, such problems are avoided or at least reduced. The inventive method is also advantageous in case of many, e.g. each rather small, labels which are to be placed in the cavities of a multi-cavity mould per cycle, for example when the mould has 20 or more cavities for mass production of plastic products.

[0022] In embodiments, the one or more labels of the sheet are connected along a closed outer contour thereof, optionally also along a closed inner contour thereof, to the remaining material of the sheet via weakened connections, e.g. being pre-cut or partially stamped out, e.g. via micro connections, wherein the weakened connections are broken upon removing the one or more labels out of the sheet. These micro connections can, for example, be formed by laser treatment of the sheet. Hereby, the process of removing the labels from the sheet is eased and the occurrence of tears in the material is reduced.

[0023] In embodiments, multiple labels are present in a single sheet.

[0024] In embodiments, all labels are simultaneously removed out of the sheet.

[0025] In embodiments, during the step of retrieving a sheet out of the magazine, a single sheet is retrieved at a time from a magazine.

[0026] In embodiments, the one or more labels are removed from the sheet by means of pressing, punching, or by means of suction. Herein punching may involve some shearing action, e.g. still avoiding the need for any cutting action by cutting edge(s) in the course of removing the one or more labels.

[0027] In an embodiment, a retrieval head provided with sheet retaining means is used for performing the step of retrieving a sheet from the magazine, wherein a removal head provided with label retaining means is used for performing the step of removing the one or more labels from the sheet, e.g. the removal head pressing or punching the one or more labels out of the sheet.

[0028] In an embodiment, the step of removing the one or more labels from the sheet is performed by bringing the retrieval head, which is holding onto a sheet, and the removal head together, such that the sheet is positioned between the retrieval head and removal head, wherein the retrieval head and removal head are configured and operated to perform the action of removing the labels out of the sheet, wherein the removed labels are retained by the removal head and the remaining material is retained by the retrieval head. In embodiments, the retrieval head comprises one or more recesses, each recess corresponding to a label, wherein the removal head presses or punches each label out of the sheet into a recess of the retrieval head, and wherein the removal head retains the one or more labels and the retrieval head retains the remaining material of the sheet.

[0029] In embodiments, further use is made of a removal station which is provided with sheet retention means for retaining a sheet, which removal station comprises one or more recesses corresponding to the one or more labels in the sheet, wherein the method comprising the steps of:

[0030] - retrieving a sheet from the magazine using the retrieval head,

[0031] - positioning the sheet by means of the retrieval head onto the removal station, so that the one or more labels in the sheet align with the one or more recesses of the retention means of the removal station,

[0032] - disengaging the retrieval head from the sheet and clearing the retrieval head from the removal station,

[0033] - operating the removal head so as to remove the one or more labels out of the sheet by pressing the labels out of the sheet into the recesses of the retention means, and retaining the removed labels with the removal head, and wherein the retaining means of the removal station retain the remaining material of the sheet.

[0034] The removal station serves as a location where the labels are removed from a sheet and allows the use of several retrieval heads and / or removal heads in combination with the removal station. For example, while the retrieval head, after handing over a sheet to the removal station, starts moving to the magazine in order to retrieve another sheet the removal head can start removing the labels from the sheet by engaging with the removal station. Also multiple retrieval heads can be used, e.g. each with an associated magazine, in conjunction with one common removal station, thereby lowering the speed requirements for the retrieval, e.g. avoiding problems associated with retrieval and / or allowing for loading of a magazine without interrupting the pace of the in-mould labelling.

[0035] In embodiments, use is made of a waste discard head, wherein the waste discard head is used to discard the waste material from the retrieval head or from the removal station. For example, the waste discard head conveys the waste material to a collection container, e.g. for recycling of the waste material.

[0036] In embodiments, the removal head is not only used for the step of removal of the one or more labels out of the sheet, but the same removal head is then also used to insert the one or more labels into one or more respective cavities of the mould of the moulding device. The advantage of this approach is that the labels do not need to be transferred to an insertion head for the insertion of the one or more labels into the respective cavity of the mould. This, for example, may avoid issues related to maintaining an accurate positioning of the labels. However, this does place stringent requirements on the operation of the removal head, as its operation then needs to be fully synchronized with the cycles of the moulding device. In view of this, in another embodiment, it is envisaged that use is made of an insertion head, wherein the method comprises a transfer of the one or more labels from the removal head to the insertion head, and wherein the insertion head is used to insert the one or more labels into one or more respective cavities of the mould of the moulding device. For example, the insertion head is part of a device as disclosed in WO2021 / 078729.

[0037] In embodiments, the removal head is configured and operated to directly transfer the labels to the insertion head, which insertion head then performs the step of insertion into the mould. This has the advantage of merely requiring one additional transfer of the labels compared to the use of the removal head for the insertion step. Nonetheless, the requirements are still quite stringent. Therefore, in yet another embodiment, it is envisaged that use is made of an intermediate label transfer device, wherein the one or more labels are transferred from the removal head to the intermediate label transfer device and from the intermediate label transfer device to the insertion head. This approach may allow for reduced complexity of the structure and operation of the heads as well as their interdependencies, e.g. in view of synchronization, etc. This approach may also be of benefit when the number of mould cavities does not match the number of labels in one sheet, for example, the number of cavities being a multiple of the number of labels in a sheet. For example, two sheets with labels are needed for a single moulding cycle. Herein, the labels from multiple sheets can be applied to the intermediate label transfer device with the insertion head moving all labels in one action into the mould.

[0038] In embodiments, the intermediate label transfer device comprises a shuttle mechanism to move the intermediate label transfer device between a pick-up position for transfer of the one or more labels from the removal head to the intermediate label transfer device and a discharge position for transfer of the one or more labels from the intermediate label transfer device to the insertion head.

[0039] In embodiments, a single sheet is provided with multiple IML labels corresponding to the number of cavities of a multi-cavity mould, so that the labels removed out of one sheet are inserted into the cavities. In embodiments, a sheet is provided with multiple IML labels having a spacing and orientation relative to one another, wherein the spacing and orientation of the labels on a sheet corresponds to the spacing and orientation of multiple cavities of the mould of the moulding device. As the spacing and orientation of multiple cavities is governed by all kinds of factors related to the moulding process, this approach may result in quite a significant percentage of the sheet being waste material. If recycling is optimized, e.g. as discussed herein, this may not be immediately problematic, e.g. from an environmental perspective. However, IML sheet material is rather expensive and therefore it is considered attractive to position the labels on a sheet in an optimal manner, taking into account a desire for a reduce percentage of waste material.

[0040] In an embodiment, the spacing and / or orientation of the labels on the sheet may differ from the spacing and / or orientation of the of the cavities of the mould of the moulding device. Herein it is envisaged that the spacing and / or orientation of the labels is adjusted once removed from the sheet in order to correspond to the cavities of the mould of the moulding device. This adjustment may be done at any convenient moment in the IML process, e.g. by means of the intermediate label transfer device.

[0041] In an embodiment, the discarding of the waste material comprises collecting the waste material in a container. The collected waste material can be used for recycling.

[0042] In an embodiment, the discarded waste material is recycled and used as material for the moulding of plastic products by means of the moulding device. For example, the waste material is shredded or otherwise made into small pieces.

[0043] For example, the waste material is mixed with plastic pellets that are used for injection moulding of plastic products, e.g. in the same moulding facility as where the IML labelled plastic products are made, e.g. for the same products that are provided with the IML labels.

[0044] In the field, it is common that the IML label material is of the same type of plastic as the plastic that is used for the moulding of the products. This, e.g., in view of optimum integration of the IML label with the product.

[0045] It is also known that the IML label material contains a layer of primer material at the side to be integrated with the product. In such case, if desired, the recycling may involve the removal of the primer prior to the recycled label material being mixed with plastic pellets for the injection moulding of products. This avoids any undue interference of the primer with the injection moulding process.

[0046] For example, the I ML label material contains a layer of primer material at the side to be integrated with the product, wherein the primer is a water soluble primer, e.g. in view of the desired to remove the IML label in the process of recycling of the plastic product. For example, the recycled product is to be bathed in water and / or sprayed with water, e.g. heated water, in order to dissolve the primer layer and thereby release the IML label from the product so that the IML label material can be handled as a separate recycle stream distinct from the rest of the product. For such an IML label in the course of the inventive process, in embodiments, the waste material can be handled in the same manner when desired, so that the primer is separated from the waste material.

[0047] Preferably, the remaining material of the sheet, so the portion(s) of the sheet other than the one or more IML labels, is non-printed, which enhances the recycling of the waste material.

[0048] In an embodiment, a device with a multi-functional head is used for the steps of retrieving a sheet from the magazine, removing the labels from the sheet, inserting the labels into the corresponding number of cavities of the mould of the in-mould labelling device, and for discarding the waste material. This has the advantage of only a single multi-functional head being used and requiring less components as compared to one or more devices providing multiple mechanical heads, e.g. each head for one task. A drawback, however, may reside in the cycle time that can be obtained with such a multi-functional head performing the retrieval, removal, insertion, and discarding. If the moulding cycle time is rather long, e.g. for relatively larger plastic products, a multi-functional head may be practical.

[0049] In an embodiment, use is made of one or more devices together providing multiple individual mechanical heads. Herein each mechanical head is used for one of the steps of: retrieving a sheet from the magazine, removing the labels from the sheet, inserting the labels into the cavities of the mould of the moulding device, and, optionally, discarding the waste material. In the field of production of plastic products with in-mould labels often (very) short cycle times are desired. Cycle times in the order of just a few seconds are commercially relevant for some high volume products, e.g. small containers for packaging food products, etc. The use of multiple mechanical heads, preferably each with its own drive mechanism, potentially allows for lower cycle times compared to a single multi-functional head as discussed above. As the individual heads can perform their tasks partially at the same time as one or more of the other heads, the operation allows for a short overall cycle time. In an embodiment, a retrieval head is used for performing the step of retrieving a sheet from the magazine, a removal head is used for performing the step of removing the labels from the sheet, and a waste discard head is used for performing the step of discarding the waste material. For example, the waste discard head discards the waste material while the retrieval head is retrieving a sheet from the magazine.

[0050] Advantageously, the labels are pressed out of the sheet and are held onto by a removal head in a single action.

[0051] When the mould has received the labels from the removal head, a process of producing plastic products in the moulding device can be started.

[0052] In an embodiment, the retaining means hold onto the sheet or label(s) by means of vacuum suction. These vacuum means of holding onto a sheet or label are customary in the field. During handling of such sheets and / or labels, the sheet and / or labels can become or made electrostatically charged and as such be handled by another charged object. For example, the insertion head is configured to cause transfer to the mould surface of the labels based on an electrostatic charge as is known in the art.

[0053] In an embodiment, the mechanical heads and / or removal station hold onto the sheet and / or labels by means of electrostatic forces or vacuum suction.

[0054] In an embodiment, on each of multiple parallel working lines a routine is performed including the steps of:

[0055] - loading of the multiple planar sheets into a magazine of the respective working line,

[0056] - retrieving a sheet from the magazine,

[0057] - removing the one or more labels from the sheet.

[0058] For example, the mould comprises a number of cavities corresponding to a multiple of the number of labels of a sheet, e.g. twice the number of labels of a sheet, e.g. wherein two parallel working lines are used.

[0059] In an embodiment, each working line comprises a magazine, at least one retrieval head, optionally a removal station, and a removal head. In an embodiment, a single sheet may be configured to hold a number of IML labels which is smaller than the number of cavities in a mould member of the moulding device. This can happen when a large number of cavities is present in a single mould member. Preparing all labels by means of a single working line, might result in excessive cycle times. A potential speedup is possible by using multiple working lines in parallel. In the field of moulding plastic products, short cycle times are an important aspect. By having one or more working lines operating in parallel the cycle time can be reduced up until where removing the labels is not the limiting time factor of a cycle. For example, two working lines are operated adjacent to each other. At the end of the working line the labels are provided separate from the waste material. Preferably a single head, for example a transfer head, can hold onto the labels prepared by multiple working lines and insert these into the cavities of a mould of the moulding device. This way the cycle times can be reduced compared to a single working line.

[0060] In an embodiment, multiple magazines are mounted adjacent to each other. The process of removing the labels from a sheet by means of one or more mechanical heads and / or removal station can be seen as an operation performed in a working line. By having several working lines adjacent to each other the processes are performed in parallel and serialized. For example, in the scenario where a mould of a moulding device comprises a number of cavities corresponding to a number of labels comprised by four sheets, four working lines can be used in parallel. Advantageously, now in a single production cycle the four working lines can remove a number of labels from a sheet and insert said labels into the cavities of a mould of a moulding device as to fill all cavities. This reduces the cycle time as compared to a sequential solution wherein a single working line has to perform the same operation four times during a single production cycle.

[0061] In an embodiment, during removal of the labels from the sheet, the central cut-out of the labels is removed from each label. Performing this action simultaneously with the step of removing the label from the sheet allows for a potential reduction in cycle time. For example, the recesses of a mechanical head or removal station are in the shape of the label and do not contain a recess in the position of the central cut-out. During removal of the label the central cut-out remains at a same level as the other waste material of the sheet while the label is pressed into a recess.

[0062] In an embodiment, the central cut-out of the label is retained with the waste material of the sheet. Having all waste material of the sheet retained on the same location, for example on the removal station, allows for easy clean up and handling of said waste material. Since low cycle times are a main driver for certain design choices the easing of the cleaning process and reducing waste discarding time is an important factor when in-mould labelling.

[0063] In an embodiment, the discarded waste material is used as material for the moulding of products in the moulding device. It is customary in the field that the material of which the inmould labels are made, are of the same material, for example polypropylene or polyester, as the moulded plastic products. This allows for the use of waste material in the moulding step when forming plastic products and reduces excess waste.

[0064] In an embodiment, means are provided to alter the relative spacing between the labels after they are removed from the sheet. For example, individual label retaining members are arranged on a mechanism configured to change the relative distance and / or orientation between the labels.

[0065] The sheets may comprise one or more plastic layers, e.g. of polypropylene and / or polyester.

[0066] The sheets may comprise a metallic layer combined with one or more plastic layers.

[0067] The sheets may comprise or consist of a paper material.

[0068] In an embodiment, the method further comprises the steps of:

[0069] - moulding plastic products by means of the moulding device,

[0070] - removal, e.g. ejection, of the plastic products out of the cavities of the mould of the moulding device.

[0071] This allows for the production of moulded plastic products by means of the in-mould labelling and moulding device.

[0072] The present invention also relates to a system for production of plastic products with in-mould labelling as described herein, which system comprises a moulding device, a magazine, and multiple planar sheets of IML label material, each sheet comprising one or more pre-printed in-mould labels and remaining material, wherein the system is configured to:

[0073] - load said multiple planar sheets of IML label material into the magazine,

[0074] - retrieve a sheet from the magazine,

[0075] - remove the one or more labels out of the sheet, wherein the remaining material of the sheet is waste material,

[0076] - insert the one or more labels into a corresponding number of cavities in a mould of the moulding device, - discard the waste material.

[0077] The present invention also relates to an I ML system for use in the production of plastic products using a moulding device with in-mould labelling as described herein, which IML system comprises a magazine configured to be loaded with multiple planar sheets of IML label material, each sheet comprising one or more pre-printed in-mould labels and remaining material, wherein the IML system is configured to:

[0078] - retrieve a sheet from the magazine,

[0079] - remove the one or more labels out of the sheet, wherein the remaining material of the sheet is waste material,

[0080] - insert the one or more labels into a corresponding number of cavities in a mould of the moulding device,

[0081] - discard the waste material.

[0082] In use, the IML system is arranged adjacent the moulding device.

[0083] In an embodiment, a robotic arm supports a multi-functional head having one or more faces, e.g. one or more of a retrieval face, a removal face, and a discard face. For example, the robotic arm comprises a drive mechanism having multiple, for example six, degrees of freedom, in order to allow the desired motions of the head. For example, adjacent the robotic arm one or more of a magazine in which a stack of sheets can be loaded, a removal station for removing the labels from a sheet, and a collector is / are present.

[0084] The production system or IML system may further comprises one or more of the technical features discussed herein with reference to the inventive method, e.g. as disclosed in one or more of the claims.

[0085] The invention also relates to a planar sheet of IML label material comprising one or more preprinted in-mould labels and remaining material.

[0086] The invention also relates to the use of a sheet as described herein for in-mould labelling.

[0087] The invention also relates to a method for production of a planar sheet of IML label material comprising one or more pre-printed in-mould labels and remaining material, wherein the labels are printed on a large size sheet, e.g. an AO format sheet, and wherein the large size sheet is cut into multiple smaller size sheets, each having at least one label, e.g. the smaller size sheets being of A2, A3, A4 or A5 format. The invention is primarily envisaged for use in injection moulding of plastic products, but can also be used in a blow moulding of plastic products.

[0088] The invention will now be explained with reference to the drawings. In the drawings:

[0089] Fig. 1 schematically illustrates an in-mould labelling system and a first step according to the invention,

[0090] Fig. 2 - 12 schematically illustrate steps according to the method,

[0091] Fig. 13 - 16 schematically illustrate steps according to another embodiment of the invention, Fig. 17 schematically illustrates a sheet comprising multiple pre-printed in-mould labels, Fig. 18 schematically illustrates a sheet comprising multiple pre-printed in-mould labels having a central cut-out,

[0092] Fig. 19 schematically illustrate steps according to another embodiment of the invention,

[0093] Fig. 20 schematically illustrates two working lines according to the method,

[0094] Fig. 21 schematically illustrates four working lines according to another embodiment,

[0095] Fig. 22 schematically illustrates the process of producing products by means of a moulding device,

[0096] Fig. 23 schematically illustrates an embodiment of a system for performing the inventive method.

[0097] In figure 1 a schematical view of an example of a system 1 for in-mould labelling according to the invention is presented.

[0098] The system 1 comprises a magazine 2 wherein a stack 3 of planar sheets 4 of I ML label material has been loaded. Each sheet 4 comprises multiple pre-printed in-mould labels 8 (see e.g. figures 17, 18) held in remaining material 9 of the sheet 4.

[0099] For example, each sheet 4 is of A3 or A4 format.

[0100] In the embodiment of figures 1 - 12 a multi-functional head 10 is used to perform the multiple steps of the inventive method. The head 10 is mounted on an associated drive mechanism to perform motions of the head 10.

[0101] A removal station 5 is shown adjacent to the head 10. The removal station 5 comprises retention means 16 configured for retaining a sheet 4 in a planar state. In particular the retention means 16 are configured to retain the remaining material 9 of the sheet 4. The removal station 5 comprises recesses 17 corresponding to the labels 8 of the sheet 4. The sheet is placed on the station so that each label 8 aligns with a recess 17.

[0102] A mould member 6 of an injection moulding device is schematically shown. The mould member has multiple cavities 7 in which an in-mould label, IML label 8, is to be placed prior to closing the mould and moulding of the plastic product. For example, the number of cavities 7 of the mould member corresponds to the number of labels 8 in a single sheet 4.

[0103] The multi-functional mechanical head comprises a retrieval head 11 with a retaining means 15 configured for retaining a sheet 4 in a planar state when being retrieved from the magazine 2.

[0104] It is illustrated that the multi-functional head 10 has several sides, which are also referred to as heads. These are, in this example, the retrieval head 11, a removal head 12, and waste discard head 13. As discussed, embodiments are envisaged wherein the heads are individual heads, e.g. each with its own drive mechanism as part of one or more devices.

[0105] In the figures 1 - 12 an embodiment of the inventive method is shown in several steps. In the first step, as shown in figure 1 , the retrieval head 11 is moved towards the magazine 2 in order to remove a single sheet 4.

[0106] In figure 2, the retrieval head 11 has retrieved a sheet 4 from the stack 3 of sheets out of the magazine 2. The retrieval head 11 comprises a retaining means 15, which is used for retaining the retrieved sheet 4, as preferred in a planar state. For example, vacuum suction is used.

[0107] In figure 3, the mechanical head 10 is rotated as to perform a following step of the inventive method. The head 10 is rotated such that the retrieved sheet 4 is held in a position opposing a face of the removal station 5.

[0108] Figure 4 shows the step of handing over the sheet 4 from the retrieval head 11 to the removal station 5.

[0109] In figure 5 the mechanical head 10 is rotated to bring the removal 12 head opposite the removal station 5. In figure 6, the removal head 12 is moved to - in combination with the removal station 5 holding the sheet 4 - remove all the labels 8 out of the sheet 4 by pressing or punching the labels 8 out of the sheet into the recesses 17 of the retention means 16 of the station 5. In this step the labels 8 also become retained by removal head 12, e.g. by vacuum suction.

[0110] Figure 7 shows the removal head 12 being moved away from the removal station 5. In the process the removal head 12 retains the labels 8 and moves them out of the recesses 17 of the retention means 16 of the station 5.

[0111] Figure 8 shows the step of aligning the removal head 12 with the cavities 7 of the mould member 6 of the moulding device, while retaining the labels 8.

[0112] In figure 9, the labels 8 are inserted into the cavities 7 of the mould 6 by means of the removal head 12. After inserting the removal head 12 is moved back into its original position. As discussed, this approach has the advantage of no intermediate transfer(s) taking place of the labels 8 between the step of removal out of the sheet 4 and the insertion into the cavities 7.

[0113] Figure 10 shows a first step of discharging the waste material 9 of the sheet 4 after the labels 8 have been removed. This material 9 is still present on the retention means 16 of the removal station 5. The waste discard head 13 is positioned opposite to the removal station 5.

[0114] As shown in figure 11 , the waste discard head 13 is brought into contact with the remaining material 9 which is now considered waste material and which is still held by the removal station 5.

[0115] Figure 12 shows the step of moving the waste discard head 13 for removal of the waste material 9 from the station 5, e.g. allowing for dropping the material 9 in a collection container for subsequent recycling.

[0116] The figures 13 - 16 show, highly schematically, an alternative embodiment of the inventive method. Here there is no need for a removal station 5. Instead, the labels 8 are removed from the sheet 4 and handled by means of the retrieval head 11 and removal head 12 cooperating together. As figure 13 shows the retrieval head 11 is used to retrieve a sheet 4 from the magazine 2.

[0117] The sheet 4, in particular the remaining material 9 thereof, is retained on the head 11 , e.g. by vacuum suction. The sheet 4 is still in a planar state.

[0118] Figure 14 shows the step of bringing the retrieval head 11 and removal head 12 together, so that the labels 8 are pressed out of the sheet 4 into corresponding recesses of the retrieval head 11 by means of the removal head 12. In the process, the labels 8 become retained on the removal head 12, e.g. by vacuum suction.

[0119] In figure 15 the retrieval head 11 and removal head 12 are moved away from one another. The retrieval head 11 holds onto the waste material 9 and the removal head 12 holds onto the labels 8.

[0120] As shown in figure 16 the removal head 12 is aligned with the cavities of the mould member 6 and inserts the labels 8 into the cavities 7 of the mould 6.

[0121] Figure 17 shows a sheet 4 with multiple labels 8 in a 2D-array.

[0122] In between the labels 8 and about the edge of the sheet 4 here the remaining material 9 of the sheet is present.

[0123] Along the outer closed contour of each label 8 weakened connections are present, e.g. embodied as micro connections formed by laser treatment. Other weakened connections, e.g. formed by die-cutting of the labels 8 or otherwise, are also envisaged.

[0124] In figure 18 another embodiment of a sheet 4 is shown. Here the sheet comprises multiple ring shaped labels 8 having an inner closed contour to allow the formation of a central cut-out 21 when the label 8 is removed out of the sheet 4. Also the inner contour is delimited by a weakened connection with a portion of the remaining material present within this inner closed contour. For example, the weakened connections along the inner contour are embodied as micro connections formed by laser treatment. Other weakened connections, e.g. formed by die-cutting of the labels 8 or otherwise, are also envisaged.

[0125] Figure 19 shows another exemplary embodiment of the invention, highly schematically.

[0126] Injection moulding device 60 includes first mould member 6 with cavities 7, as well as second mould member 26 with core members 27. The device 60 further comprises extruder 61 and a feeder 62 for plastic particles, e.g. pellets, that are to be molten. As common, the mould can open and close.

[0127] Figure 19 shows magazine 2 in which a stack of sheets 4 is loaded. A removal station 5 is illustrated. Retrieval head 11 of a device provided with a drive mechanism for the head 11 operates to retrieve a sheet 4 from the magazine 2 and deposit the sheet 4 in planar state on the removal station. There, as discussed, retention means retain the remaining material 9 of the sheet 4 with the labels 8 of the sheet being aligned with recesses of the station 5. Once the sheet 4 has been deposited, the head 11 release the sheet and is moved away. The removal head 12 then is used to press or otherwise release the labels 8 out of the sheet 4. Herein, the labels 8 are retained by the head 12 and the head 12 then conveys the labels 8 to an intermediate label transfer device 40. This device 40 generally serves to move the labels 8 to an insertion head 50, here with dummy or false cores, which operates to bring the labels to the opened mould and to place the labels 8 in the cavities 7 of the mould member 6.

[0128] The device 40 receives the labels 8 from the removal head 12 at a pick-up position 41 and then shuttles the labels 8 to a discharge position 42 where the labels 8 are handed over to the insertion head 50. To this end the device 40 includes a shuttle mechanism.

[0129] The figure 19 also illustrates that a discard head 37 moves the remaining material 9 of the sheet, now waste, to a collector 31. The collected waste is recycled, e.g. shredded by shredder 38. As, as preferred, the waste material is non-printed, the shredded waste material can be mixed with the main feed of plastic particles that is fed via feeder 62 to the extruder 61.

[0130] Figure 20 shows two working lines working a parallel to remove labels 8 from sheets 4.

[0131] By way of example, it is assumed that the number of labels 8 of the two sheets 4 together corresponds to the number of cavities 7 of the mould member 6.

[0132] Each working line comprises a magazine 2, a mechanical head 10, and a removal station 5.

[0133] In the shown embodiment a device with a single multi-functional mechanical head 10 is shown, however in alternative embodiments the use of multiple mechanical heads is also foreseen. Each mechanical head 10 retrieves a sheet 4 from their respective magazine 2. The process of removing labels 8 from the sheet 4 of each respective working line is similar as explained above where a single working line is used. After removing the labels from the sheet the mechanical heads insert the labels into the cavities 7 of the mould 6 of the moulding device. Both mechanical heads insert their labels into the same mould, and each head has its own cavities 7 into which it inserts said labels 8.

[0134] Figure 21 shows another embodiment wherein multiple working lines are used. In the shown embodiment four working lines are used for removing labels 8 from a sheet 4 and inserting the labels of four sheets into the cavities 7 of a mould member 6.

[0135] The embodiment is shown wherein a retrieval head 11 and a removal head 12 are used. The process of removing the labels from the sheet of each respective working line is identical to the process as described in the embodiment for a single working line using a retrieval head 11 and removal head 12. During the step of inserting the labels into the cavities 7 of a mould 6, the removal head 12 of each working line inserts the labels 8 into its respective cavities 7 of the mould 6.

[0136] In figure 22 a schematic block diagram of the method is shown. In this specific embodiment four working lines are shown. Each working line has its respective magazine 2 into which sheets 4 are loaded. In a first step a sheet 4 is removed from each magazine. Then the label removing process is performed by means of one or more mechanical heads 10 and / or a removal station 5 for each respective working line. During this process the labels 8 are removed from the sheets 4. The waste material 9 is then discarded and collected in a waste container 31. The waste material can then be prepared for recycling, i.e. by separating a primer layer (when present) from the waste material and / or shredding said material. This yields recycled material 32. Each respective working line now has created individual labels 8a, 8b ,8c, 8d separated from the remaining material 9 of the sheet.

[0137] In the figure 22 it is schematically shown that the removed labels are handled by an insertion head 14. The head 14 holds onto the labels 8a, 8b, 8c, 8d and may also adjust the relative spacing and / or orientation such that the labels are then positioned to be inserted into the respective cavities 7a, 7b, 7c, 7d of the mould member 6 of the moulding device 60.

[0138] After the labels have been inserted into the cavities of the mould member 6, the mould will close and the cavities of the mould are filled with molten plastic material for producing plastic products. The moulding of products can be performed with or without recycled material 32 obtained from the waste material 9. After the mould has been filled with material the mould comprising material 33 will shape and form the products. After this process the mould will open and the plastic products 34 are removed from the mould member 6.

[0139] Figure 23 shows a schematic view of an embodiment of a system for performing an embodiment of the inventive method.

[0140] The system comprises a robotic arm 70 supporting a multi-functional head 10 having several faces. The head of the shown embodiment comprises a retrieval face 11 , a removal face 12, and a discard face 13.

[0141] The robotic arm comprises a drive mechanism having multiple, for example six, degrees of freedom, in order to allow the desired motions of the head 10.

[0142] Adjacent the robotic arm 70, a magazine 2 in which a stack of sheets 4 is loaded, a removal station 5 for removing the labels from a sheet, and a collector 31 are present.

[0143] The robotic arm retrieves a sheet 4 out of the magazine 2 by means of the retrieval face 11. The arm then places this sheet onto the retention means 16 of the removal station 5. The robotic arm then changes the position of the head such that the removal face 12 is used to remove the labels from the remaining material of the sheet. The head then holds onto the labels by means of the removal face 12, and the retention means 16 hold onto the remaining material of the sheet. The robotic arm then moves the labels towards the injection moulding device 60 and inserts the labels into the cavities 7 of a mould member 6.

[0144] The injection moulding device 60 may comprise an intermediate label transfer device 40, as is shown in figure 19. If an intermediate label transfer 40 is present, the robotic arm transfers the labels by means of the removal face 12 onto the device 40 at a pick-up position 41 thereof. The device 40 then shuttles the labels to a discharge position 42, where the labels are handed over to an insertion head which insert the labels into the cavities of a mould of the injection moulding device 60.

[0145] The robotic arm of the shown embodiment then returns to the removal station 5 where the remaining material of the sheet is held. This remaining material is the waste material. The robotic arm 70 then positions the waste discard face 13 over the waste material in order to pick up said material from the removal station 5 by means of the discard face 13. The robotic arm then moves the head such that the waste material is discarded in the collector 31. The waste material can then, for example, be recycled and used as material for the moulding of plastic products by means of the moulding device. The robotic arm then, for example, performs the sequence of the steps above again.

[0146] In the embodiment above only a single robotic arm is used. It is also possible that multiple robotic arms are used. For example, a second robotic arm is used for the removal station 5. The second robotic arm would then comprise a head having a retention means to cooperate with the discard head of a first robotic arm. The retention means would then hold onto the remaining material, and at a later stage discard this. This prevents the need for the first robotic arm to return to the removal station for cleanup of the waste material, allowing a time save per cycle. It is also envisaged that multiple robotic arms operate in parallel, as is mentioned.

Claims

C L A I M S1 . A method for in-mould labelling, wherein the method comprises the steps of:- loading multiple planar sheets (4) of IML label material, for example a stack (3) of sheets, into a magazine (2), wherein each sheet comprises one or more pre-printed in-mould labels (8) held in remaining material (9) of the sheet,- retrieving a sheet (4) from the magazine,- removing the one or more labels (8) out of the sheet, wherein the remaining material (9) of the sheet is waste material,- inserting the one or more labels (8) into a corresponding number of cavities (7) in a mould (6) of a moulding device (60),- discarding the waste material (9).

2. Method according to claim 1 , wherein the sheets (4) which are loaded into the magazine (2) are of the A2, A3, A4, or A5 size, preferably A3 or A4.

3. Method according to claim 1 or 2, wherein multiple labels (8) are present in a single sheet (4), e.g. in a two-dimensional array, and wherein, preferably, the labels (8) are simultaneously removed out of the sheet (4), e.g. wherein the sheet (4) is provided with multiple IML labels (8) corresponding to the number of cavities of a multi-cavity mould, so that the labels removed out of one sheet are inserted into the cavities (7)4. Method according to any one or more of claims 1 - 3, wherein the one or more labels (8) each have a closed outer contour as well as at least one closed inner contour extending about a portion of the remaining material of the sheet, the closed inner contour defining a cutout of the label once removed out of the sheet, e.g. the label (8) being ring shaped and having a single cut-out, e.g. a central cut-out.

5. Method according to one or more of the preceding claims, wherein the one or more labels (8) of the sheet are connected along a closed outer contour thereof, optionally also along a closed inner contour thereof, to the remaining material of the sheet via weakened connections, e.g. being pre-cut or partially stamped out, e.g. via micro connections, the weakened connections being broken upon removing the one or more labels out of the sheet.

6. Method according to one or more of the preceding claims, wherein the one or more labels (8) are removed from the sheet by means of pressing, punching, or by means of suction.

7. Method according to one or more of the preceding claims, wherein a retrieval head (11) provided with sheet retaining means is used for performing the step of retrieving a sheet from the magazine, and wherein a removal head (12) provided with label retaining means is used for performing the step of removing the one or more labels (8) out of the sheet, e.g. the removal head (12) pressing the one or more labels out of the sheet.

8. Method according to claim 7, wherein the step of removing the one or more labels out of the sheet is performed by bringing the retrieval head (11), which is holding onto a sheet, and removal head (12) together, such that the sheet is positioned between the retrieval head and removal head, wherein the retrieval head and removal head are configured and operated to perform the action of removing the labels out of the sheet, wherein the removed labels are retained by the removal head and the remaining material is retained by the retrieval head.

9. Method according to claim 7 or 8, wherein the retrieval head (11) comprises one or more recesses, each recess corresponding to a label (8), and wherein the removal head (12) presses each label out of the sheet into a recess of the retrieval head, and wherein the removal head retains the one or more labels and the retrieval head retains the remaining material of the sheet.

10. Method according to claim 7, wherein further use is made of a removal station (5) which is provided with sheet retention means for retaining a sheet, which removal station comprises one or more recesses corresponding to the one or more labels in the sheet, wherein the method comprising the steps of:- retrieving a sheet from the magazine using the retrieval head (11),- positioning the sheet by means of the retrieval head onto the removal station (5), so that the one or more labels in the sheet align with the one or more recesses (17) of the removal station,- disengaging the retrieval head from the sheet and clearing the retrieval head (11) from the removal station,- operating the removal head (12) so as to remove the one or more labels (8) out of the sheet by pressing or punching the labels out of the sheet into the recesses (17), and retaining the removed labels with the removal head (12), and wherein the retaining means of the removal station (5) retain the remaining material (9) of the sheet.

11. Method according to any one or more of claims 7 - 10, wherein use is made of a waste discard head (37), wherein the waste discard head is used to discard the waste material (9).

12. Method according to any one or more of claims 7 - 11 , wherein use is made of an insertion head (50), wherein the method comprises a transfer of the one or more labels from the removal head (12) to the insertion head (50), and wherein the insertion head is used to insert the one or more labels into one or more respective cavities (7) of the mould of the moulding device, and wherein, optionally, use is made of an intermediate label transfer device (40), wherein the one or more labels are transferred from the removal head (12) to the intermediate label transfer device and from the intermediate label transfer device to the insertion head (50), e.g. the intermediate label transfer device comprising a shuttle mechanism to move the intermediate label transfer device between a pick-up position (41) for transfer of the one or more labels from the removal head to the intermediate label transfer device and a discharge position (42) for transfer of the one or more labels from the intermediate label transfer device to the insertion head.

13. Method according to one or more of the preceding claims, wherein a sheet is provided with multiple IML labels (8) having a spacing and orientation relative to one another, and wherein the spacing and orientation of the labels on a sheet corresponds to the spacing and orientation of multiple cavities (7) of the mould of the moulding device, or wherein the spacing and / or orientation of the labels on the sheet differs from the spacing and / or orientation of the of the cavities of the mould of the moulding device, wherein the spacing and / or orientation of the labels is adjusted once removed from the sheet in order to correspond to the cavities of the mould of the moulding device.

14. Method according to one or more of the preceding claims, wherein the discarded waste material (9) is recycled, e.g. shredded, and is used as material for the moulding of products by means of the moulding device (60).

15. System for production of plastic products with in-mould labelling according to one or more of the preceding claims, which system comprises a moulding device, a magazine, and multiple planar sheets of IML label material, each sheet comprising one or more pre-printed in-mould labels and remaining material, wherein the system is configured to:- load said multiple planar sheets of IML label material into the magazine,- retrieve a sheet from the magazine,- remove the one or more labels out of the sheet, wherein the remaining material of the sheet is waste material,- insert the one or more labels into a corresponding number of cavities in a mould of the moulding device,- discard the waste material.

16. A planar sheet (4) of IML label material comprising one or more pre-printed in-mould labels and remaining material.

17. Use of the sheet of claim 16 for in-mould labelling.

18. A magazine loaded with a stack of sheets of claim 16 for use in in-mould labelling.

19. Method for production of a planar sheet of IML label material comprising one or more pre-printed in-mould labels and remaining material, wherein the labels are printed on a large size sheet, e.g. an AO format sheet, and wherein the large size sheet is cut into multiple smaller size sheets, each having at least one label, e.g. the smaller size sheets being of A2, A3, A4 or A5 format.

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