Containers, packages, and boxes for storing and shipping products typically use box sealing tape, such as an adhesive tape, to secure the flaps or covers so that the container, package, or box will not accidentally open during normal shipment, handling, and storage. Box sealing tape maintains the integrity of a container, package, or box throughout its entire distribution cycle. Box sealing tape can be used on other parts of container, package, or box and on other substrates, and can be used to function in a manner similar to labels. These tapes can be made in roll or pad form, and can have information printed or otherwise applied to, or contained within or on, the tape.
These containers, packages, or boxes generally display information about their contents. This information most commonly located on the container, package, or box might include lot numbers, date codes, product identification information, and bar codes. The information can be placed onto the container, package, or box using a number of methods. These include preprinting the container, package, or box when it is manufactured, printing this information onto the container, package, or box at the point of use with an inkjet code that sprays a pattern of ink dots to form the image, or by using a flexographic ink rolling coding system. Other approaches include the use of labels, typically white paper with preprinted information either applied manually, or with an online automatic label applicator.
A recent trend in conveying information related to the product is the requirement to have the information specific for each container, package, or box. For example, each container, package, or box can carry specific information about its contents and the final destination of the product, including lot numbers, serial numbers, and customer order numbers. The information is typically provided on labels that are customized and printed on demand at the point of application onto the container, package, or box. This is typically known as the ability to print “variable” information onto a label before it is applied onto the container, package, or box. Two patents that disclose printed labels are U.S. Pat. Nos. 5,292,713 and 5,661,099. U.S. Pat. No. 2,492,908 discloses a label applying mechanism.
One system for printing variable information involves thermal transfer ink printing onto labels using an ink ribbon and a special heat transfer print head. A computer controls the print head by providing input to the head, which heats discrete locations on the ink ribbon. The ink ribbon directly contacts the label so that when a discrete area is heated, the ink melts and is transferred to the label. Another approach using this system is to use labels that change color when heat is applied (direct thermal labels). In another system, variable information is directly printed onto a box or label by an inkjet printer including a print head. A computer can control the ink pattern sprayed onto the box or label.
Both thermal transfer and inkjet systems produce sharp images. Inkjet systems include piezo, thermal, continuous, and drop-on-demand. With both inkjet and thermal transfer systems, the print quality depends on the surface on which the ink is applied. It appears that the best system for printing variable information is one in which the ink and the print substrate can be properly matched to produce a repeatable quality image, especially bar codes, that must be read by an electronic scanner with a high degree of reliability.
Regardless of the specific printing technique, the printing apparatus includes a handling system for guiding a continuous web of label tape to the print head, as well as away from the print head following printing for subsequent placement on the article of interest (for example, a box). To this end, the web of label tape is normally provided in a rolled form (“tape supply roll”), such that the printing device includes a support that rotatably maintains the tape supply roll. Further, a series of guide components, such as rollers, transfer plates, festoons, etc., are utilized to establish a desired tape path both upstream and downstream of the print head, with the terms “upstream” and “downstream” in reference to a tape transport path initiating at the tape supply roll and terminating at the point label application to the article of interest (e.g., a box). An exact configuration of the guide components is directly related to the form of the label tape.
In particular, label tape is provided as either a linered tape or as a linerless tape. As suggested by its name, linered tape includes both a tape defined by a print side and an adhesive side, and a release liner encompassing the adhesive side. The liner serves as the carrier for the label tape. With this configuration, the printing device normally includes components that, in addition to delivering the web to and from the print head, also peel the liner away from the label tape. While widely accepted, linered tape material is relatively expensive due to the cost associated with inclusion of the release liner. Further, the liner adds to the overall thickness, thereby decreasing the available length of label tape for a given tape supply roll diameter. A decreased label tape length requires more frequent changeovers of the tape supply roll (where the exhausted tape supply roll is replaced by a new roll), and therefore a loss in productivity. Additionally, because the liner material is typically paper, resultant fibers, debris, and dust can contaminate the printing mechanism, potentially resulting in a reduced print head life. Also, a die cut operation is typically performed on the label stock to generate labels of discrete size. The die cut operation is an additional manufacturing step (and therefore expense), and prevents implementation of a variable label length processing approach.
To overcome the above-described problems associated with linered label tape, a linerless format has been developed. Generally speaking, linerless label tapes are similar to the linered configuration, except that the liner is no longer included. Thus, the linerless label tape is defined by a non-adhesive side or backing formulated to receive printing (“print side”) and an opposing side (or “non-print side”) that often times carries an adhesive (“adhesive side”). By eliminating the liner, linerless label tapes have a greatly increased length for a given roll diameter, and eliminate many of the other above-listed processing concerns associated with linered label tape. However, certain other handling issues are presented.
In particular, as the web of linerless tape is pulled or extended from the supply roll, the adhesive side is exposed, and will readily adhere to surfaces, and in particular the guide components associated with the printing device. A common difficulty encountered in the handling of linerless label tape is “wrap-around”, whereby the web adheres to and wraps around a roller otherwise in contact with the adhesive side. For example, with thermal transfer printing, a platen roller or drive roller is normally associated with the print head for supporting the label tape during printing by the print head and for driving the tape out the printer exit. In this regard, the adhesive side of the linerless tape is in contact with, and carried by, the drive roller. Invariably, instead of simply releasing from the drive roller, the adhesive side adheres to and wraps around the drive roller. This highly undesirable situation leads to printer malfunctions, such as misprinting, tape jams, etc. Wrap-around of the platen roller or drive roller is most commonly found in printing devices conforming with “next label out” protocol where, after the label is printed, it is immediately cut and applied to the article in question. In other words, there is no accumulation of printed labels between the print head and the application device, in contrast to typical “loose loop” systems where printed labels accumulate prior to cutting and thus includes guide components, such as festoons, to tension the linerless label tape off of the drive roller.
Many efforts have been made to address the “wrap-around” concern associated with linerless label tape in next label segment out printing systems, including those described in U.S. Pat. Nos. 5,674,345; 5,524,996; 5,487,337; 5,497,701; and 5,560,293. In summary, each of these references incorporates a device, such as a stripper bar, a stripper plate, or an air source, that interacts with the linerless label tape after it has undesirably adhered to the platen or drive roller. That is to say, the common technique for addressing drive roller wrap-around is to position a device adjacent the platen roller that effectively “scrapes” the linerless label tape off of the platen or drive roller in the event of platen or drive roller wrap-around.
Other efforts have been made to address the “wrap-around” concern associated with linerless label tape in printing systems, such as those described in U.S. Pat. Nos. 5,437,228; 5,940,107; 5,879,507; and EP 0637547 B1 and EP 0834404.
Various apparatuses and methods for printing on tape and applying a length of printed tape to articles are known in the art. For example, apparatuses for printing and applying tape are described in U.S. Pat. No. 6,049,347 (Ewert et al.), “Apparatus for Variable Image Printing on Tape,” U.S. Pat. No. 6,067,103 (Ewert et al.) “Apparatus and Process for Variable Image Printing on Tape,” PCT Publication WO 98/42578 (Lenkl) “Device and Method for Applying Linerless Labels,” and PCT Publication WO 00/34131 (Faust et al.) “Variably Printed Tape And System For Printing And Applying Tape Onto Surfaces.” 3M Company located in St. Paul, Minn. has sold print and apply case sealing applicators and print and apply corner sealing applicators under the brand name 3M-Matic as CA2000 Corner Label Applicator and PS2000 Print & Seal Applicator.
Print and apply label applicators are commercially available from Etipack, S.p.A. located in Cinesello Balsamo (Mich.), Italy under the brand names Drinjet, Drinfit, Drinedge and AP Euro. Tape dispensers are also commercially available from Etipack, S.p.A. located in Cinesello Balsamo (Mich.), Italy under the brand name Strappy. Although the commercial success of available print and apply tape or label applicators have been impressive, it is desirable to further improve the performance of applicators handling linerless label tapes which print on the tape and apply the tape to objects, such as packages or boxes, while minimizing or eliminating the concern of platen or drive roller wrap-around.