Abstract:
A method of producing stacks of printed, ready-to-use adhesive-backed labels which are separated from one another by release coatings that are in registry with adhesive strips but on opposite sides of each individual label to prevent the labels in the stack from adhering to one another to an excessive degree; i.e., to permit the labels to be separated from one another for application to the edge or face of a storage shelf. The overall production process may be carried out into different stations at different locations, the first location producing feed stock for the second location.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    This application claims the benefit of U.S. provisional patent application Ser. No. 61/886,704 filed Oct. 4, 2013. 
     
    
     FIELD OF THE INVENTION 
       [0002]    This application relates to the design and manufacture of adhesive labels from strip stock moving through a multi-station machine or sequence of machines. 
       BACKGROUND OF THE INVENTION 
       [0003]    Printed adhesive-backed labels are commonly used on retail store shelves to convey information to customers regarding products stored and displayed on the shelves. Because products, product locations and prices change often, such labels are frequently applied, removed, and replaced with new labels. 
         [0004]    Many prior art shelf labels are manufactured using pre-made, pressure sensitive materials, of which many are available in the marketplace. These labels are made with an attached release liner that is typically thick to keep the product flat and allow the labels to feed through a laser printer without jamming. Part of the release liner is peeled off by an end user or, conversely, the labels are peeled off of the liner when applied. 
         [0005]    Flatness is important because it allows the labels to stick to and/or hang from a shelf face in a store in such a way as to make it easy for customers to read information on the labels. 
         [0006]    A thick release liner creates waste and makes labels, when packaged in substantial numbers, very heavy. This increases shipping costs and can induce curl, which is undesirable for the reasons set forth above. 
         [0007]    Some prior art labels use delamination/relamination to create specific zones of adhesion. 
         [0008]    The prior art can be used to produce finished labels in sheets or strips containing multiple labels and arranged in columns or rows. These sheets can be cumbersome in that a person applying the labels needs to disassemble the sheets into individual labels and apply the labels one at a time to the faces of the shelves. This process is time consuming and expensive because it is typically done by unskilled labor when the store is closed. 
         [0009]    The prior art teachings also use laser printing to digitally print the various information on the labels. Because of this, heat resistant materials, flat laying materials, and good toner adhesion properties are needed. This limits the type of material which can be used to make labels and, with some printers, the labels are limited to black and white. A typical material used to make the labels is vinyl, which has environmental disadvantages. 
       SUMMARY OF THE INVENTION 
       [0010]    The present disclosure provides a teaching as to how to make adhesive-backed labels economically and efficiently in strip form and in ready-to-use stacks wherein multiple adhesive-backed printable or pre-printed labels lie on top of each other with a release coating between the labels directly beneath and geometrically coextensive with the adhesive layer on an adjacent label. The stack of labels from the process can be quickly and easily used by retail store personnel to apply labels to the faces or edges of product storage shelves. 
         [0011]    In broad terms, the method can comprise a number of steps of making a strip or a stack of adhesive-backed labels from strip stock wherein the strip stock comprises printable flexible sheet material having first and second opposed sides. The steps comprise (a) applying discreet layers of adhesive to a first side of the stock in single or multiple rows at regularly spaced intervals wherein the layers are identical in area, geometry and orientation. As shown herein, the strip stock can be wide enough to make multiple rows of labels simultaneously. 
         [0012]    Another step of the process involves the application of discreet layers of silicone-based release coating at regularly spaced intervals along another side of the strip stock in single or multiple rows, the discreet release coating layers also being of identical area, geometry and orientation to one another. 
         [0013]    When these two steps are completed and the labels are cut from the stock and stacked, the regularly spaced layers of adhesive and release coating are essentially coextensive in that they lie on opposite sides of the sheet stock but geometrically correspond with one another. 
         [0014]    The method may also involves steps of curing the release layer, identifying the position of each label by reference to one or both of the location of the edges of the adhesive and release coatings and the printing and, using the location information, arranging a cutter so as to cut the labels from the stock at the appropriate place. 
         [0015]    In general, this sequence of steps further comprises a stacking step which results in a stack of labels which are easily peeled from one another and immediately applied to the edges or faces of shelves. As will hereinafter be made clear, the overall method can be divided into two parts carried out in sequence either at the same or in different locations. The first of the divided phases may result in a roll of strip stock with adhesive and cured release areas applied. This roll is then transported to the machinery involved in the next phase and unrolled wherein the remainder of the steps are carried out. Printing may occur at either of the two locations. 
         [0016]    Other advantages, features and characteristics of the present invention, as well as methods of operation and functions of the related elements of the structure, and the combination of parts and economies of manufacture, will become more apparent upon consideration of the following detailed description and the appended claims with reference to the accompanying drawings, the latter being briefly described hereinafter. 
     
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
         [0017]    The description herein makes reference to the accompanying drawings wherein like reference numerals refer to like parts throughout the several views and wherein: 
           [0018]      FIG. 1  is a front plane view of an individual label; 
           [0019]      FIG. 2  is a back plane view of the label of  FIG. 1 ; 
           [0020]      FIG. 3  is a front plane view of another individual label; 
           [0021]      FIG. 3A  is a side view of the label of  FIG. 3 ; 
           [0022]      FIG. 4  is a perspective view of a stack of labels made in accordance with this invention; 
           [0023]      FIG. 5  is a sectional view through a portion of the stack of labels; 
           [0024]      FIG. 6  shows how a label made in accordance with this invention may be applied to a shelf; 
           [0025]      FIG. 7  is a process machinery diagram in perspective showing the movement of strip stock  50  from a roll  52  through multiple stations of a complete processing line; 
           [0026]      FIG. 8  is a block diagram of the process carried out by the machinery in  FIG. 7 ; 
           [0027]      FIG. 9  is a system diagram of a first portion of a split, sequentially used set of machinery; 
           [0028]      FIG. 10  is a second process equipment diagram or drawing in perspective showing the second set of equipment used in a split sequence of manufacturing labels in accordance with the present teaching; and 
           [0029]      FIG. 11  is a detailed drawing of a portion of the system of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION 
       [0030]      FIG. 1  shows a front plane view of an individual label  10 . Label  10  may be of any shape and/or size but is shown in essentially rectangular form with dimensions of approximately 5×12 cm. and designed to be applied to the front face of a shelf  34  and hang essentially vertically in the orientation shown in  FIGS. 1 and 6 . In one embodiment, approximately the lower three quarters of a front face of label  10  is covered with an inkjet coating  12  which readily receives flexo printing  14 . In one embodiment, an inkjet printing method is used to print on label  10 . In alternative embodiments, other printing methods, such as electrophotography, dry toner, thermal transfer, and direct thermal printing are used. Label  10  is printed using digital technology  26 . The top quarter of the front face of the label  10  is covered with a release coating  16 . In one embodiment as shown in  FIG. 2 , approximately the back three quarters of a face stock  18  of label  10  is uncoated and approximately the top one quarter is covered with a pressure sensitive adhesive  20 . In alternative embodiments, the ratio of area that label  10  is covered with adhesive  20 , the release coating  16 , or printed on may vary. The face stock  18  may be the any of a variety of materials, including white or colored opaque paper or a polymer film which can be clear, white, or colored. The materials have sufficient strength to not be easily cut, yet are flexible and light. In  FIGS. 1 and 2 , there is no liner attached or otherwise applied to either the front or the back face of the face stock  18  of label  10 . 
         [0031]    The optional inkjet coating can be water-based, applied by roller, and dried. Adhesive  20  may be any of a wide variety of available materials which are pressure sensitive and self-adhesive, such as various acrylics and hotmelts. 
         [0032]    In an alternative embodiment,  FIGS. 3 and 3A  show a slightly different label  22  with the same shape and size as label  10  shown in  FIGS. 1 and 2 . Label  22  can be made of an opaque material. An inkjet coating  24  is applied to approximately the lower three quarters of a face stock to receive thereafter an inkjet/digital printing  26  in a readily readable form and size. A release coating  28  is applied to approximately the top quarter of the face stock with a sharp straight border relative to the inkjet coating  24 .  FIG. 3A  shows the side view of label  22 , such that the adhesive coating  30  on approximately the back top quarter of a face material  25  is directly opposite and identical in area to the release coating  28 . In one embodiment, the inkjet coating  24  is located over approximately the bottom three quarters of the front of the face stock. The references to “one quarter” and “three quarters” are approximate and are not intended in a limiting sense. The figures may, for example, be one third and two thirds or other fractions as desired. 
         [0033]      FIG. 4  shows a stack  32  of labels  10  after they have been printed and stacked. In one embodiment as shown in  FIG. 4 , there is a stack  32  consisting of twelve labels with the optional inkjet coating and a release coating  16  facing up. In alternative embodiments, the number of labels in stack  32  could be more or less than twelve.  FIG. 5  shows a detailed sectional view of stack  32  with the front sides of label  10  stacked to the left. Each adhesive layer  20  directly overlies and conforms in dimension and shape to the underlying release coating  16 , which can vary in size, to create a gap  15  between the back side of each label  10  and the optional inkjet coating  24  on the front side of the next adjacent label  10  in stack  32 . This gap  15  allows each label  10  to be readily separated one from the other during the application process. In an alternative embodiment, the gap  15  is very small and probably not easily detectable because the adhesive thickness is only about ten percent of the thickness of face material  25 . 
         [0034]    The application process is represented in  FIG. 6  where a label  10  is shown applied to the front side of a representative retail display/storage shelf  34 . In this illustration, only the top ¼ to ⅓ of the label is shown adhered to the front side of the shelf  34  such that the label hangs straight down displaying the printing on the optional inkjet coating toward the consumer. Again, it will be understood that the rectangular label in the above-mentioned size is merely illustrative and that the labels may be of any size and/or shape as suits the needs or desires or the individual store. 
         [0035]    Referring now to  FIGS. 7 through 11 , an overall multi-station system is shown for making two parallel strips or rows of labels as described above from a double-wide strip of printable, flexible label stock  50  which is being taken from a supply roller  52  at the left side of the drawing. In this case, the label stock is wide enough to make two parallel rows of labels and also to leave a latticework of waste material ( FIG. 11 ) after the labels are cut and removed from the material  50 . A double-wide strip is chosen for purposes of illustration and not for limitation; i.e., the stock could be four wide, if desired. 
         [0036]    The first station or step involves the passage of the strip  50  of material over an engraved cylinder  43  where two parallel transverse areas of adhesive are applied to one side only of the strip  50  of material. These areas of adhesive are applied at regularly spaced intervals; i.e., longitudinal spacing along the strip  50  and each strip has a relatively sharply defined top and bottom lateral edge. These areas are those shown in  FIGS. 2 ,  3 A, and  6  at  20 . The material  50  with the strips or areas of adhesive applied then goes through a drying oven  56  which is attached to a hot air dryer  58 . In the event a solid adhesive is used, drying is not needed. 
         [0037]    After the adhesive-coated stock strip  50  emerges from the oven, it passes over a series of rollers  60  which carry the material over the top of the oven and from there to an inkjet printer  61 . Again, the inkjet printer is representative of just one type of printer that can be used to apply information or indicia of some kind to the label material on the side opposite the adhesive. 
         [0038]    After the printing step. The strip of stock then is conveyed to a second engraved cylinder  64  where liquid silicone is applied in pairs of lateral lines extending across the stock. These lateral lines are also regularly spaced as to correspond exactly to the lines or areas of adhesive but on the opposite side thereof. By way of further explanation, the lines of liquid silicone represent release coatings and the layers of silicon are identical in area, geometry and orientation to the lines of adhesive on the other side. To put even more clearly, the lines of silicone “register” with the lines of adhesive on the opposite side. However, as a practical matter, the lines of silicone-based release coating can be slightly larger than the lines of adhesive to make the manufacturing process easier. The release areas are those shown at  16  in  FIG. 1  and at  28  in  FIGS. 3 and 3A . 
         [0039]    The silicone release material is cured at station  62  and then passes over a series of rollers to a die cutter  66  but first goes past a sensor  68  which locates the printing and/or other locator characteristic on the strip of stock to make sure that the die cutter cuts the labels free from the strip stock in exactly the right place so that the cut is in register with the digital and/or flexo printing. 
         [0040]    This cutting step generates a matrix of waste material  70  which goes up to a roller  72  while the labels go to stacking stations  75  which are capable of producing two stacks of labels as shown in  FIGS. 4 and 5 . Two stacking stations are made possible with the use of a flapper to direct the labels to one or the other of the two stackers. When one of the stackers is full, a switch may be thrown to route the labels to the other stacker so that the previously-stacked labels can be removed and boxed. 
         [0041]      FIG. 8  is a block diagram of the various steps carried out in the various stations as described above. The step of providing a strip or web of material is shown in  FIG. 7  at  52 , while the step of applying adhesive is shown at  43 . The third step of drying the adhesive is shown at  56 ; the next step is one of printing on the label stock at station  61 ; the next step is one of curing the printing as necessary; the next step is applying the silicone release strips to the stock at station  64 ; the next step is curing the silicone release at station  62 ; the next step is to cut the labels into individual shape at station  66 , in this case shown as rectangular, for purposes of illustration only. The next step is to remove the waste matrix  70  and roll it up for recycling if possible. The final step is the stacking of the labels using starwheel stackers at station  75 . There is a vacuum box  82  that holds the labels in place where they enter the stacking apparatus; i.e., starwheel stackers. 
         [0042]    Referring now to  FIGS. 9 and 10 , these drawings are nearly duplicative of each of the beginning and ending portions of the overall system of  FIG. 7  and show how the overall process may, for practical purposes, be divided into two parts which can be carried out in the same plant or in different plants by different people. The system of  FIG. 9  produces a strip of double-wide label stock with adhesive and silicone applied as described above but without printing, cutting or stacking. The result is a roll  80  of label stock. 
         [0043]    Referring to  FIG. 10 , the roll  80  of label stock is the feed product which first goes to the printing station  76 . It then goes past a UV curing station  78 . From this, the double-wide printed label stock goes to a sensor  68  for registration purposes to determine exactly where the label stock is to be cut and from there, the label stock passes through the engraved cutting cylinder  66  to die-cut the labels. The matrix  70  of waste is then separated and goes up to the roller  72  while the individual double rows of labels proceed forward to the two alternately employed starwheel stackers  75 A and  75 B. 
         [0044]    While the invention has been described in connection with what is presently considered to be the most practical and preferred embodiment, it is to be understood that the invention is not to be limited to the disclosed embodiments but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims, which scope is to be accorded the broadest interpretation so as to encompass all such modifications and equivalent structures as is permitted under the law.