MXPA00009945A - Method and apparatus for wrapping a label onto a container with a glueless leading edge - Google Patents

Abstract

A labeling machine (10) and method of labeling containers (12) with a label (15) that has a glueless leading edge and is caused to wrap around a container (12) by the application of an aqueous solution that is applied to the container (12) prior to applying the label (15) to the container (12). The aqueous solution is preferably applied to the label panel portion of the container (12). The surfacetension of the aqueous solution causes the label (15) to wrap around the container (12). Glue is applied to the trailing edge of portion and is confined to the portion of the label (15) forming a sleeve in situ that is not adhered by glue to the container (12). The aqueous solution is applied to the container (12) to be labeled by means of an aqueous solution supply system (28) having a roll-on pad including a sponge (66).

Description

METHOD AND APPARATUS FOR WRAPPING A LABEL ON A CONTAINER, WITH AN ANTERIOR EDGE WITHOUT AN ADHESIVE TECHNICAL FIELD • The present invention relates to a method and apparatus for placing labels in containers. BACKGROUND OF THE ART Many different methods and machines have been developed to apply labels on containers. The fact of placing labels on containers has many advantages in comparison with the direct decoration of the containers by applying paint or printing. The placement of labels in containers is generally less expensive and can offer an aesthetically pleasing appearance to the container which offers a convenient way of labeling a container with all the required information and decorative graphic designs. One type of label is a pressure sensitive adhesive label that generally offers a full coating of adhesive protected prior to application through a backing layer. The backing layer is removed from the label before application and the label is affixed to the container by means of the adhesive on the back of the label. Another type of label is a preformed sleeve label which is then slipped over one end of the container and will be glued or shrunk in place. Sleeve labels are generally made from more expensive materials and are difficult to form and assemble on a container compared to labels fed on rolls. Wrap labels are applied onto the containers by wrapping the label around the container after the first adhesion of the leading edge with the trailing edge being fixed by means of adhesive on the outside of the leading edge or on the wall of the container. The containers are frequently recycled by melting or washing them for reuse. In the case of recycling, it is usually necessary first to remove the labels and glue, especially if they are of a different composition from the container. Often when the labels are removed, a residue of glue remains in the container if the label has been stuck on the container. The value of the recycled containers increases if the containers do not present contaminants such as glue and label fragments. During the labeling process, the glue applied on container bodies can result in a wrinkling which can be caused by the glue fixing portions of the label on the container during thermal shrinkage while other portions of the container can move. The wrinkling can also be caused by application of full liner adhesive if the glue layer does not have a constant thickness. The application of labels on containers with • Glue also increases the amount of glue that is required for the labeling operation which also increases the cost. The machine and labeling system disclosed in this application are focused on solving these and other problems and disadvantages associated with the methods and machines of labeling of the prior art. DISCLOSURE OF THE INVENTION According to the present invention, a machine for labeling containers is disclosed, which includes a container feeding conveyor for feeding containers to the container. machine. A label feeder supplies labels having a leading edge portion, a posterior edge portion being considered from a label supply source. A vacuum drum receives the labels from the label feeder. An applicator The moistening solution is placed on the labeling machine near the feed conveyor to apply an aqueous solution on each of the containers as they are fed into the machine by the feed conveyor. The solution is applied on a portion of label panel of each container. A glue applicator is placed adjacent to the vacuum drum and has protruding portions spaced around the periphery of the vacuum drum corresponding to the back edge portions of the labels. The protruding portions cause the portions of the trailing edge to come into contact with the glue applicator thus coating the back edge portions with glue. The vacuum drum applies labels on the containers causing the aqueous solution in the containers to humidify the labels causing the labels to wrap around the containers and separate from the cylindrical surface of the vacuum drum. The trailing edge portion is wrapped in the leading edge portion of the labels and fixed to the leading edge portion of the labels by glue. In accordance with other aspects of the invention, a method for labeling containers is offered. The method comprises the steps of feeding labels having an inner portion and an outer portion on a labeling machine having a vacuum drum to support the labels during the labeling process. The containers having a label panel portion are fed to the labeling machine from a container supply source. An aqueous solution is applied over the containers to humidify the label panel portion of the containers. Glue is applied over a limited portion of the inner portion of the labels while the labels • they are supported in the vacuum drum. The labels are wrapped around the containers causing the aqueous solution in the containers to humidify the surface of the labels. The limited portion of the inner surface of the labels having glue is fixed on a portion of the outer surface of the label. • According to another aspect of the present invention, the label source is preferably a roll of labels. Alternatively, the label supply source can also be a stock of cut and stacked labels or another source of label supply. The preferred wetting solution applicator is a roller pad. Alternatively, the wetting solution applicator may be a spray applicator. The glue applicator is preferably a hot-melt glue applicator and the glue applied is of Preferably a hot melt adhesive. The hot melt glue is preferably applied over the back portion of the label in such a way that no glue is applied to the container. While, in its preferred modality, no glue is applied on the In the case of a container, a certain amount of glue splashes or a minimum amount of glue may be applied between the label and the container, but this glue is not intended to cause the transfer of the label on the container. • the recipient. The method may also include the step of heating the label to shrink the label material around the contours or in portions of reduced diameter of the container. The above objects and advantages of the present invention are • 10 will be better understood with reference to the accompanying drawings and the following detailed description of the invention. DESCRIPTION OF THE DRAWINGS Figure 1 is a partial plan view of a labeling machine and a partial elevation view of a system of aqueous solution applicator made in accordance with the present invention. Figure 2 is an elevation view of a container having a label partially applied in accordance with the present invention. Figure 3 is a plan view of a vacuum drum made in accordance with the present invention. Figure 4 is a sectional view of a container having a label applied in accordance with the present invention. 25 PREFERIDADE MODE THE INVENTION As reference to figure 1, a labeling machine is shown which is for labeling containers 12. The containers 12 are fed into the labeling machine 10 on a feed conveyor 14. The labels are supplied by a label feeder 16. The label feeder 16 can incorporate a cutter 18 for cutting labels received from a roll of labels 20 through a tensioning device 22 as is well known in the art. Alternatively, a label feeder 16 can be a stock of cut and stacked labels. A vacuum drum 24 is used to support discrete labels 15 after it is received from the feeding of labels 16 until it is fixed on the containers 12. As the containers are fed to the machine they come into contact with the solution applicator 16 having preferably the shape of a roller pad. An aqueous solution of water of about 1% to 5% is supplied to the solution applicator 26 from a solution supply system 28. The solution supply 28 includes a mixing tank 30 in which water and glycerin are mixed in the desired proportion. A solution is provided to the solution applicator 26 by means of a pump 32. A premix tank 34 is preferably provided to provide a stock of glycerin in a more concentrated form which is then diluted by further addition of water prior to delivery to the applicator. of solution 26. A mounting post 36 is provided on the base of the labeling machine to mount the solution applicator on the labeling machine. With reference to Figure 2, a container 12 with a label 15 partially peeled is shown to illustrate the wetting solution 40 on the label panel portion 42 of the container 12. The label 15 has glue 46 applied on the label splice. With reference to Figure 1, the glue applicator 50, preferably a hot melt glue wheel applicator, is shown adjacent to the vacuum drum 24. Referring now to FIG. 3, the vacuum drum 24 has a surface generally cylindrical 52 and is designed to fit two to three labels. Overhanging portions 54 are provided at locations spaced around the perimeter of the cylindrical surface 52. The generally cylindrical surface includes cut-off portions 56 where a labeling segment is held in the vacuum drum 24. The vacuum drum cover 58 is formed preferably with Tygon, a relatively rigid elastomeric material that can be machined to provide a desired contour. Referring now to Figures 2 and 4, the label 15 is shown with its leading edge portion 60 and its trailing edge portion 62. The leading edge portion 60 is the first portion of the tag 15 upon entering into contact with the container while the trailing edge portion 62 is the last portion of the label to be transferred onto the container 12 as the label 15 is applied. The trailing edge portion 62 is fixed on the leading edge portion 60 by melt adhesive in hot 46. The solution delivery system 28 is described with reference to Figure 1. The tube 64 provides the aqueous solution or wetting solution 40 to a sponge 66 that is part of the solution applicator 26. The sponge is preferably A PVA sponge which is a durable, compressible material that preserves the wetting solution for transfer to the container prior to the application of the label. A manifold 70 is provided to distribute the aqueous solution. A strainer is provided (not shown) for filtering foreign particles from the flow of the aqueous solution prior to its delivery to the sponge 66. A pressure regulator is provided to control the fluid pressure in the solution supply system 23. A valve 78 is provided for control the flow of the aqueous solution. As reference now figure 1, as the containers 12 are fed into the labeling machine 10, they are initially guided by a feed guide 80 and are fed into the machine in a synchronized relationship by • middle of a star wheel 82. A container guide 84 5 is placed on the opposite side of the feed conveyor 14 from the feed guide 80 and the solution application pad 26. Since the containers follow the guide of container 84 around solution applicator 26, containers 12 rotate in such a manner that substantially all of container 12 is moistened through aqueous solution. After humidification of the container 12 with the aqueous solution, the container 12 is displaced in contact with the label 15 in the vacuum drum 24. Since each container 12 is moves around the vacuum drum, the label 15 is wrapped around the container. An application roller pad 86 is provided to hold the container against the vacuum drum while allowing the container to rotate. After the application of the labels 15 they can be thermally shrunk on the containers by applying heat on the labels with a hot air blower or by passing the labeled container through an oven as shown in FIG. the previous 25 technique.

While embodiments of the invention were illustrated and described, it is not intended that these embodiments illustrate and describe all possible forms of the invention. To the On the contrary, the words used in the specification are descriptive and non-limiting words and it is understood that several changes can be made without departing from the spirit and scope of the invention. fifteen twenty

Claims (13)

1. CLAIMS A machine for labeling containers comprising: a container feed conveyor that feeds containers into the machine; a label feeder that supplies labels having a leading edge portion and a trailing edge portion from a label supply source; a vacuum drum that receives labels from a label feeder; a wetting solution applicator that is positioned to apply an aqueous solution on each of the containers as they are fed to the machine by the feed conveyor, said solution is applied on a portion of the label panel of the containers; a glue applicator placed adjacent to the vacuum drum, said vacuum drum has a generally cylindrical surface bearing one or more labels, said generally cylindrical surface of the vacuum drum having one or more protruding portions spaced around the periphery of the vacuum drum in locations corresponding to the back edge portion of the labels which causes the back edge portion to come into contact with the glue applicator that applies glue to the back edge portion; and the vacuum drum that applies labels onto the containers causing the aqueous solution in the containers to wet the labels causing the labels to wrap around the containers as they are separated from the cylindrical surface of the vacuum drum until the edge portion Then wrap the front edge portion of the labels and fix it there by glue.
2. 2. A machine for labeling containers, according to claim 1, wherein the source of supply of labels is a roll of labels.
3. 3. The machine for labeling containers according to claim 1, wherein the wetting solution applicator is a roller pad.
4. 4. The machine for labeling containers according to claim 1, wherein the wetting solution is a 1% to 5% solution of glycerin and water.
5. The machine for labeling containers according to claim 1, wherein the glue applicator is a hot melt glue applicator and said glue is a hot melt glue.
6. 6. A method for labeling containers, comprising the steps of: feeding labels having an internal surface and an external surface to a labeling machine that • has a vacuum drum during the process of 5 labeling; feeding containers having a label panel portion to the labeling machine from a container supply source; Apply an aqueous solution to the containers to ^ 10 moisten the label panel portion of the containers; apply a limited portion of the inner surface of the labels while they are supported on the vacuum drum; 15 wrap the labels around the containers causing the aqueous solution in the containers to moisten the internal surface of the labels; and fix the limited portion of the inner surface of the labels that have glue applied there on 20 a portion of the outer surface of the label.
7. The method for labeling containers according to claim 6, wherein the step of applying glue on the back edge portion of the label is carried out in such a way that when the label is 25 applies to the containers, no glue is applied to the container.
8. 8. The method for labeling containers according to claim 6, wherein the step of feeding • labels is carried out by feeding a 5 weaving a label material from a roll of label material.
9. The method according to claim 6, wherein the step of applying an aqueous solution to the containers is carried out with a roller pad. ^^ 10
10. 10. The container labeling method according to claim 6, where the step of applying glue is carried out by means of a hot melt glue applicator.
11. 11. The method for labeling containers according to claim 6, wherein the aqueous solution is applied over the total circumference of the containers. The method for labeling containers according to claim 6, wherein the portion of the label on which the glue is applied is the portion of 20 back edge of the labels. The method according to claim 6, wherein the method further comprises the step of applying heat to the labels after their application on the containers causing the labels to shrink 25 on the container including any portion of the reduced diameter of the containers,