NL1012869C2 - Manufacture of labels for placement in injection molds, involves using retaining element for enclosing film web against a supporting carrier - Google Patents

Abstract

A label is manufactured by using a retaining element with which a film web is enclosed against a supporting carrier. Manufacture of labels (2) for placement in an injection mold involves supplying and applying a strip of film (4) having two sides on a supporting carrier (6). A retaining element (14) is applied to the second side of the film web that is remote from the carrier. The part of the film web enclosed between the carrier and the retaining element is cut loose and the enclosed part, i.e., label, is taken hold of by the retaining element and is picked up from the carrier for transfer into a mold. Independent claims are also included for: (A) a method for placing a label in a mold for in-mold labeling injection molded products; (B) a method of injection molding comprising: (i) filling a cavity; (ii) opening the mold; (iii) moving the movable bounding parts in the injection molding directions, while the formed product is held between the engaging parts and is moved partly out from the cavity; and (iv) moving the engaging parts to render a clear product; (C) an apparatus for manufacturing labels; (D) an injection mold; and (E) an injection molded product provided with a printing applied through in-mold labeling.

Description

Title: Method and device for manufacturing and placing labels in a mold.

The invention relates to a method of manufacturing labels for placement in a mold. . Such a method is known from practice.

In this known method, labels are manufactured and stacked loosely on top of each other, the top label of a stack being each time taken up by means of a transfer device and transferred to a mold cavity, where the label is suitably placed. A plastic 10 is then sprayed against this label to form a desired article. Such a method is usually referred to as in-mold labeling, for example. This known method has the drawback that the labels have to be manufactured separately and have to be stacked, whereby the labels have to be removed from the stack without this causing wrinkling, tearing, folding or otherwise damaging the labels. In addition, the conditions in which the labels are stacked, picked up and transferred into the mold must be particularly well conditioned in order to obtain good placement.

It has already been proposed to cut or punch labels from a foil web prior to placement, then to pick up these labels with the aid of a transfer device and to place them in the mold cavity in an appropriate manner. Such a method offers the advantage that the labels can be supplied in a particularly simple manner, namely, for example, from a roll and can be cut on the spot immediately prior to installation. In such a method, however, the drawback arises that when the labels are cut out or punched they are at least partly exposed, so that undesired positional changes can occur. Moreover, the drawback remains that prior to and during 1012869 2 the pick-up and transfer of the label, damage thereof may occur, for instance due to folds, creases and the like. Furthermore, after cutting or punching, the label has to be taken up from the foil web before it can be transferred, which is time consuming.

A further drawback of this known method is that the labels must have a relatively high form stiffness. After all, in this known method, the labels are only engaged on a part of their surface, such that the longitudinal edges are exposed.

The present invention contemplates a method of manufacturing labels, wherein the drawbacks of the described method are avoided, while retaining its advantages. To that end, a method according to the present invention is characterized by the measures according to claim 1.

By making use of a retaining element with which a part of the foil strip can be enclosed against the supporting carrier, which enclosed part 20 is subsequently cut loose from the foil strip, the advantage is achieved that deformations, creases and the like can easily be prevented, even if not ideally sharp cutting means are used. By gripping the label thus cut loose and formed with the retaining element and by subsequently taking up the label from the carrier with the retaining element, the label is prevented from having to be repacked, so that it is always held in the desired position. This means that there is no danger that the label can come off prematurely, for instance from the carrier and still deform by wrinkling, folding or the like. The retaining means preferably also form transport means for moving and optionally placing the cut-off labels in a mold.

A method according to the invention therefore offers the advantage that labels can be manufactured particularly quickly and simply in a particularly accurate manner for placement in a mold, regardless of the thickness of the film from which the labels are cut.

In a preferred embodiment, a method according to the present invention is characterized by the measures according to claim 2.

The use of a retaining element with an outer contour, which substantially corresponds to that of the desired label, offers the advantage that the label-forming part can easily be cut along the outer contour, whereby particularly sharp cuts are obtained and damage of the label is even better prevented . Moreover, the retaining element will also extend along the outer contour of the label when the label is picked up and transferred, thereby protecting it well. This further simplifies particularly accurate placement of the label in a mold or transfer device.

The retaining element is preferably provided with 20 vacuum means for retaining the label, preferably such that it is stretched somewhat, at least taut on the retaining element, so that deformations of the label are easily prevented. Of course, the label can also be held in other ways, for example by static charge, adhesion and the like, optionally in combination.

Preferably, the label-forming part is gripped before it is cut, in particular using at least the retaining element. The carrier can also be provided for at least temporarily holding the label-shaped part, for instance vacuum means.

In further elaboration, a method according to the present invention is further characterized by the measures according to claim 10.

101 2869 4

With such a method, a label can be transferred to an insertion device with which the label can be placed in the mold, which insertion device can for instance be of a known type.

The invention further relates to a method for placing a label for in-mold labeling in the mold, characterized by the measures according to claim 14.

With such a method, a label can be placed in a mold for in-mold labeling in a particularly accurate and rapid manner, whereby cycle times for the manufacture of the in-mold-labeled products can be shortened, which is economically advantageous. Moreover, in such a method particularly thin films can be used for the manufacture of the labels, which is material and cost-saving. Moreover, this offers the advantage that relatively little waste is generated. Furthermore, the product to be formed is hardly affected by the label.

A method according to the present invention is preferably used for labels with a thickness of less than 30 micrometers, more in particular a thickness of less than 20 micrometers and preferably less than 15 micrometers. In a method according to the present invention it is even possible to use foils, at least labels, with a thickness of, for example, 10 micrometers or less. It will be clear that a smaller thickness of the foil, from which the labels are manufactured, is advantageous because less material is required for this, more labels, at least foil, can be stored in a relatively limited space, while the labels are moreover lighter. A further advantage of such a method is that various techniques can be used for printing the film, such as flat and gravure techniques, printing techniques and the like. This gives a particularly great freedom in design of the labels.

1012869 5

The invention further relates to a device for manufacturing labels for placement in a mold, characterized by the measures according to claim 17.

A device according to the present invention offers the advantage that labels can be manufactured and transferred to a mold in a particularly simple and accurate manner, wherein damage or other deformations of the labels are simply prevented. Because the labels are continuously held during and after cutting by the retaining means in a position in which they have to be placed in the mold, the advantage of a device according to the present invention is that this device can be used almost independently of the ambient conditions . The labels cannot be influenced by, for example, drafts, undesired relative humidity, static or magnetic charge and the like, because the retaining means prevented this. This offers the advantage that no special measures need to be taken in the vicinity of the device, at least not in the vicinity of the transfer device.

In further elaboration, a device according to the present invention is characterized by the measures according to claim 20.

Using a punch or cutting stamp to cut the labels out of the foil offers the advantage that the labels can be cut in one movement. Because the label is enclosed between the carrier and the retaining means 30, the label is thereby simply prevented from being damaged by the stamp, for instance because the stamp no longer has optimum sharpness.

The invention further relates to an injection-molded product, characterized by the features of claim 23.

101286P

6

Such a product offers the advantage that it has a pleasant appearance by the label, while, for instance, product information, recognition means and the like are integrally formed with the product, wherein the properties of the labeled wall will hardly be influenced by the label. After all, particularly thin labels have been used.

Further advantageous embodiments of a method and device according to the invention are given in the subclaims.

To clarify the invention, exemplary embodiments of a device and method according to the invention will be further elucidated with reference to the drawing. In the drawing: Figs. 1 is a schematic sectional side view of a label forming device; Fig. 2 schematically shows, in cross-sectional side view, an opened mold during placement of a label; Fig. 3 schematically shows, in cross-sectional side view, the mold according to Fig. 2; Fig. 4 is a plan view of a foil strip with label for use in a method and device according to the invention; and Fig. 5 schematically shows, in perspective view, retaining means according to the invention.

In this description, like or corresponding parts have like or corresponding reference numerals.

Figure 1 shows a molding device 1 for forming labels 2 from a foil web 4. The molding device 1 comprises carrier means 6, for instance a flat table over which a foil web 4 can be supplied from a foil roll 10 by means of supply means 8. On the opposite side of the carrier means 6, the foil web, at least the remainder thereof, can be discharged with the aid of suitable foil discharge means 12.

1012869 7

On the side of the film web 4 remote from the carrier means 6, restraining means 14 are placed, which are arranged in a movable manner, as will be further described hereinafter. Figure 5 shows the retaining means 14 in a perspective view, from the closing side 16 which faces the film web 4 during use, in the retaining means 14 receiving means 18 are provided, in the embodiment shown as vacuum means. These receiving means 18 comprise a number of vacuum cups 20 which are open on the side facing the pressure surface 16 and which are connected to a vacuum line 22 with a vacuum pump 24, schematically shown in figure 1. On the pressure surface 16, the outer contour 26 of a labels 2 are indicated. The vacuum cups 20 are arranged at least along the inner edge of this outer contour 26 in a substantially contiguous series. Incidentally, vacuum cups 20 may also be provided on the other surface within the outer contour 26, as shown in broken lines in Figure 5. It will moreover be clear that other types of vacuum means can also be provided, for instance in the form of a perforated plate, an air-permeable membrane or the like. The outer contour 26 can lie flat in the pressure surface 16, but it can also be, for example, in the form of a groove or bend.

Cutting means 28 are included in the carrier means 6, which are movable with the aid of operating means 30, in particular cylinder / piston assemblies 32. With the aid of a pump 34, a pressure medium can be introduced into the piston / cylinder assemblies 32, whereby the cutting means 28 with a cutting edge 36 can be brought above the surface of the supporting means 6. The cutting means 28 preferably have a shape equal to the outer contour 26 of the label 2.

A molding device 1 according to the invention can be used as follows.

1012869 8

A foil strip 4, preferably having a small thickness, for instance less than 30 micrometers, is fed flat over the surface of the carrier means 6, the cutting means 28 being retracted below said surface. Subsequently, the retaining means 14 with the printing surface 16 are arranged against the side of the film web 4 facing away from the surface 38, wherein the retaining means 14 can optionally be pressed. Subsequently, with the aid of the vacuum pump 24, underpressure 10 is built up in the vacuum cups 20, at least in the receiving means 18, such that the foil enclosed between the carrier means 6 and the retaining means 14 is gripped by the receiving means 18, at least along the inner circumference of the outer contour 26. Subsequently, cutting means 28 are forced in the direction of the retaining means 14 with the aid of the operating means 30, such that the cutting edge 36 is pressed against the outer contour 26, thereby cutting the label 2 within the outer contour 26 from the foil strip 4. Then the retaining means 14 moved away from the carrier means 6, the label 2 being held in a flat position by the receiving means 18. Optionally, in the carrier means 6 and / or in the retaining means 14, vacuum cups 20 or other retaining means may be provided around the outside of the outer contour 26 of the label 2, for retaining the residual material 56 during cutting (fig. 4). The label 2 can then be transferred by means of the retaining means 14 to an injection mold 40 as shown, in particular in Figures 2 and 3.

The injection mold 40 comprises a first closing part 42 in which a cavity 44 is arranged and a second closing part 46, provided with a smooth, flat surface 48 on the side facing the first closing part 42. Feeding means 50 for injecting 1012869 9 plastic into the cavity 44 with the mold closed, connect to the cavity 44 at a suitable location and are known per se.

The retaining means 14 with the label 2 received thereon is moved between the moved closing parts 42, 46 of the mold 40, with the label 2 facing the smooth surface 48 of the second closing part 46. Subsequently, the label 2 is pressed against said smooth surface 48, such that it will adhere thereto, for example due to underpressure and / or static charge.

As soon as the label 2 is firmly connected to said surface 48, the vacuum means 22, 24 are regulated such that the pressure in the vacuum cups 20 increases, whereby the label 2 is released by the receiving means 18. The retaining means 14 can then be moved away between the mold parts 42, 15, while the label 2 remains in tight contact with the second closing part. Subsequently, the mold 40 is closed, as shown in figure 3. Subsequently, plastic can be introduced into the cavity 44 with the aid of the supply means 50, against the side of the label 2 facing away from the second closing part 20 46. At least partly, preferably fusion between the plastic and the label 2, such that a strong, inseparable bond is obtained between them. In the embodiment shown in figure 3, the label 2 is somewhat clear of the walls 54 of the mold cavity 44. However, it is also possible to design the mold 40 such that, for example, a part of the longitudinal edge of the label 2 between the mold parts 42, 46 is included. The label 2 can also lie, for example, at a greater distance from the walls 54 of the mold cavity 44.

The film web 4 is preferably printed prior to the formation of the labels 2. The film web can, for example, be rolled up printed onto the film roll 10 and fed therefrom. In the embodiment shown, for example, the film web 4 is printed on the side facing the carrier means 6 during cutting. This means that the heated plastic is injected against the unprinted side of the label 2 in the mold. However, it is also possible to print the opposite side, while moreover both sides of the labels 2 can be printed.

Figure 4 shows a top view of a foil strip 4 with a label 2 therein, cut loose along the contour 26. The outer circumference of the retaining means 14 is shown on the foil strip 4 in broken lines. As described above, it can be understood that the contour 26 corresponds to the cutting edge 36 of the cutting means 28. Seen in transport direction, the residual material 56 of the foil strip 4 is shown after the label 2 has been removed therefrom. In figure 4 a capital letter 'T' is drawn as printing. It will be clear that any form of printing is possible here.

A device and method according to the present invention offer in particular the advantage that very thin films can be used for the formation of labels. For example, labels can be cut from foil strips with, for example, a thickness of 30, 20 or 15 micrometers. Even labels with a thickness of 10 micrometers or less can be cut. After all, with the aid of the retaining means 14, in particular the receiving means 18, the foil web 4 is kept taut during the cutting or punching of the labels 2, so that damage thereof is easily prevented. The advantage of thin labels is that they require little material, that little waste is created, that they occupy only little volume and have little influence on the end product, while still obtaining good printing and design. In addition, storage and transport of such foil strips are easily possible.

The invention is by no means limited to the exemplary embodiments shown in the description and the drawings. Many variations thereof are possible within the framework of the invention outlined by the claims.

For instance, the retaining means 14 can be arranged for placing the label in the mold cavity, wherein the plastic is, for example, injected from the opposite side or introduced through the label into the mold cavity. The or each mold cavity can be divided over several mold parts. Multiple 10 labels can also be placed. Since use is made of the retaining means, irregularly shaped labels can also be cut in a simple manner, whereby openings can for instance also be provided therein. Also, by a suitable choice of the carrier means and adapted, for example, single or double curved retaining means, a label can be cut which, for example, is single or double curved, or at least placed on such a curved surface in a mold. A particularly great design freedom is hereby obtained. Moreover, in the surface against which the label is to be placed in the mold, vacuum means or the like holding means can also be provided for holding the label, for instance when irregularities such as cavities or bulges are to be obtained therein. The vacuum cups can be arranged such that when a negative pressure is realized therein the label is slightly stretched therein, whereby it is even better prevented that folds or the like occur therein.

In the shown embodiment the cutting means are included in the carrier means. It will be clear, however, that these may also be provided with the retaining means. Moreover, the retaining means can be formed such that the cutting means can cooperate with the outer circumference thereof. The cutting means can also be arranged in a fixed manner, the label being cut loose by pressing the retaining means and the foil web against the carrier means. The label 2 is preferably gripped with the receiving means immediately prior to cutting loose, but this can also take place during or directly after the cutting loose. A mold according to the invention can be of single or multiple design. In the embodiment shown, the label is directly transported to the mold with the retaining means and placed therein. It will be clear that the label can also be transferred in the meantime to another insertion device on which the label is clamped by means of comparable vacuum means or the like and subsequently placed in the mold.

All kinds of products can be formed with a method and device according to the present invention. For example, packaging such as plastic boxes, holders, consumer products, vehicle parts, plate parts and the like can be provided with labels, at least prints, which prints are fixedly connected to the relevant product. A method according to the present invention is generally applicable for labeling of injection molded products. The retaining means are preferably designed in such a way that pre-cut labels can also be received therewith, for instance from a stack, and can be introduced into the mold. Labels of all kinds and thickness can be used.

These and many variations are considered to fall within the framework of the invention outlined by the claims.

1012869

Claims (23)

1. Method for manufacturing labels for placement in a mold, in particular in an injection mold, in which a strip of foil is supplied and with at least part of a first side is placed on a supporting support, after which a retaining element on the van the carrier is brought away from the second side of the part of the foil web supported by the carrier, in particular slightly pressed, whereby the part of the foil web enclosed between the carrier and the retaining element is cut loose, whereby the part enclosed, to be referred to as label received by the retaining element and therewith picked up from the carrier. 2. Method as claimed in claim 1, wherein a retaining element is used which has an outer contour which substantially corresponds to that of the desired label, wherein the label-forming part is cut loose along the outer contour. 3. Method as claimed in claim 1 or 2, wherein the enclosed, label-forming part is gripped by means of vacuum means arranged at least on the retaining element. 4. Method as claimed in claim 3, wherein the label-forming part is gripped by means of at least vacuum means extending along the outer contour of the retaining element, such that the label-forming part is pulled at least over the retaining element. 5. A method according to any one of the preceding claims, wherein the label-forming part is gripped using static charge of the retaining element and / or the label-forming part. 1012869 A method according to any one of the preceding claims, wherein the label-forming part is gripped using adhesion between the label-forming part and the retaining element. A method according to any one of the preceding claims, wherein the label-forming part is gripped prior to cutting. 8. Method according to claim 7, wherein the label-forming part is taken up by the carrier prior to cutting loose. A method according to claim 7 or 8, wherein the label-forming part is held by the retaining element prior to cutting loose. 10. A method according to any one of the preceding claims, wherein the label of the retaining element is transferred to an insertion device for placing the label in a mold, wherein the label is taken over by the insertion device in approximately the same position. A method according to any one of the preceding claims, wherein the foil web is printed before the labels are formed. 12. A method according to claims 10 and 11, wherein the printing is applied to the second side of the foil web 13. A method according to any one of the preceding claims, wherein the label, at least the label-forming part, is slightly stretched, at least on the retaining element, preferably during or immediately prior to the holding of the label-forming part by the retaining element. 14. Method for placing a label for in-mold labeling of injection-molded products in a mold, wherein the or each label to be placed is manufactured by a method according to any one of the preceding claims and subsequently in the mold against at least a wall part 1012869 is applied and secured against it, preferably by underpressure, adhesion or static charge. 15. A method according to any one of the preceding claims, wherein labels are manufactured from a foil web with a thickness of less than 30 micrometers, more in particular, less than 20 micrometers and preferably less than 15 micrometers. The method of claim 15, wherein labels are made from a foil web with a thickness of less than 10 micrometers. 17. Device for manufacturing labels for placement in a mold, in particular an injection mold, comprising: feed means for a foil web; 15. carrier means on which the foil web can be at least partly supported; retaining means for enclosing a part of the part of the foil web supported on the carrier means during use; 20. cutting means for cutting loose from the foil web the part of the foil web enclosed between the carrier means and the retaining means; wherein the retaining means comprise receiving means for retaining the enclosed part, to be called the label, such that the label can be picked up from the carrier means substantially without deformation by means of at least the retaining means, separate from the further foil web. 18. Device as claimed in claim 17, wherein the receiving means comprise vacuum means, at least near a peripheral edge of a surface of the retaining means which is moved against the film web during use, preferably distributed over substantially the entire said surface. 19. Device as claimed in claim 17 or 18, wherein the retaining means comprise a surface which is held against the label during use, the label being slightly stretched over said surface during use, wherein the cutting means are adapted to form along the outer contour of said cut the label flat. 20. Device as claimed in any of the claims 17-19, wherein the cutting means comprise a punching or cutting punch. 21. Device as claimed in any of the claims 17-20, wherein an insertion device is provided, adapted to take over a label received therewith from the retaining means, such that this can be transferred into an open mold with the aid of the insertion device. 22. Device as claimed in any of the claims 17-21, wherein at least the insertion device is provided with a surface for taking over the label, which surface is smoothly finished, wherein fixing means are provided for holding and holding the label in a slightly stretched condition, which securing means are configured to span the label at some distance from said face while the securing means in a state where no tag is held are substantially equal to said face. 23. Injection molded product, provided with in-mold labeling printing, wherein the in-mold label has a thickness of less than 30 micrometers, in particular less than 20 micrometers, more in particular less than 15 micrometers and preferably less than 10 micrometers. 1012869