Patent Application
20250104577
Label capabilities are dependent upon a variety of adhesive-based factors, such as adhesive type, adhesive pattern, adhesive patch shapes, adhesive flood coat, adhesive coat weight, mixtures of adhesives, and adhesive activation mechanism (e.g., pressure, heat, etc.). Capabilities that require a high tack are often obtained through using a high tack adhesive that is flood coated on a backside of the label.
Hot melt adhesive is a high tack adhesive often flood coated on the backsides of shipping labels. Hot melt adhesives bond to diverse ranges of substrates (cardboard, metal, plastics, fabric, paper, wood, etc.), which is why tapes use hot melt adhesive. Hot melt adhesive is difficult to work with due to its viscosity during application to backsides of labels, which is why labels that typically include a hot melt adhesive are flood coated on the backsides of the labels. However, flood coating hot melt adhesive on the backsides of labels requires utilization of more adhesive product, which increases label manufacturing costs. Additionally, hot melt adhesive that covers the edges of the label can melt in hot operating environments cause the adhesive to leak or ooze around the edges of the label.
In various embodiments, a system and apparatus are provided for varying hot melt adhesive coat weights on a backside of a label. In an embodiment, a label is provided that includes varying adhesive coat weights disposed on the backside of the label. First channels along the backside of the label include no adhesive, second channels along the backside of the label include an adhesive of a first coat weight, and third channels along the backside of the label include a second coat weight. The first coat weight is greater than the second coat weight. In an embodiment, the first coat weight is equivalent to a flood coating of the adhesive in the second channels.
Hot melt adhesive is typically flood coated on the backsides of labels. Flood coating requires more adhesive product and is therefore expensive for label manufacturers. Additionally, flood coated edges of a label can be problematic in warm or hot operating environments in which the glue, around the edges, melts, and oozes out from the edges.
These issues are solved with the labels provided herein. The labels include lanes of varying coat weights for hot melt adhesive on the backsides of the labels. Experimentation has revealed that the coverage area and location of the lanes with varying coat weights on the backside of a label actually increases the label's peel force by 50% and requires approximately 20% less hot melt adhesive than a conventional flood coated hot melt adhesive label. Thus, the varying coat weights of hot melt adhesive on a label improves performance of the label and also reduces the amount of hot melt adhesive needed to manufacture the label.
The liquid hot melt adhesive oozes up through aperture 111 onto the lip 110-1 of top surface 110.
The apparatus 300 includes a horizontal top surface 310 which covers and is laid onto of the top surface 110 of the bottom unit 100. Similarly, the apparatus 300 includes a vertical wall 314 that covers and sits in front of vertical wall 112 of the bottom unit 100. Moreover, the apparatus 300 includes a horizontal wall or shelf 314 that sits on top of horizontal wall or shelf 113 of the bottom unit.
The apparatus 300 is affixed to the bottom unit through manufactured apertures or holes 311 in the top surface 310 and apertures or holes 316 in the shelf 315. Thus, bolts, screws, or other fasteners securely attach apparatus 300 on top of bottom unit 100.
When the top plate 130 of the top unit for the slot die is pressed down onto the top surface 110 of the bottom unit 100, the apparatus 300 is sandwiched in between the underside of the top plate and the top surface 110 of the bottom unit 100. Thus, the apparatus 300 is similar to a customized shim placed in between the bottom unit 100 and the top unit of the slot die.
The top surface 310 includes side edge appendages 313 that are sized to extend out over and cover aperture 111 (e.g., the hole from which the hot melt adhesive in liquid form bubbles or oozes up onto the top surface 110 and over lip 110-1. This is illustrated in
Top surface 310 also includes additional extending appendages 312 that also cover corresponding portions of aperture 111. This ensures that only partial or no hot melt adhesive is pushed over lip 110-1 and out through slot 125 onto the web of label substrate in areas across the web that correspond to appendages 312.
Notably, the apparatus 300 can include more or less extending appendages 312-1, 312-2, and 313-2 from what is illustrated. Furthermore, the widths of the appendages 312-1, 312-2, and 313-2 can vary to cover more or less of the aperture 111 associated with the hot melt glue reservoir 120.
Hot melt adhesive is pumped up from the glue reservoir 120 through aperture 111 of a slot die's bottom unit 100 to overflow the liquid glue onto the top surface 110 of the bottom unit. A top plate 130 of the slot die's top unit presses down onto the top surface 100 with apparatus 300 overlaid and affixed to the top surface 110 of the bottom unit 100. This causes the glue to be dispensed or ejected out of slot 125 onto a backside surface of a web of label substrate for labels. The two side edges 313 and the extending appendages 312, 312-1, 312-2, 313-3, and 312-4 completely block and/or partially block the flow of glue that exits the slot 125 onto the label substrate. When the flow is partially blocked via an extending appendage 312-4 via a manufactured or milled underside channel 312-4-1, the amount of glue that flows is dependent upon the thickness A of the channel 312-4-1. This results in the backside surface of the label substrate having no glue in first areas where the flow of glue was completely blocked by extending appendages 313, 312-1, 312-2, 312-3, full flood coated glue in second areas where there was not extending appendage, and lower coat weighted glue from the second areas in third areas where there was an extending appendage 312-4 with a carved-out underside channel 312-4-1.
Once now appreciates how apparatus 300 can be custom manufactured or adjusted to manufacture a roll of labels with each label in the roll having varying coat weights of hot melt adhesive glue disposed thereon. The apparatus 300 is an overlay or a shim manufactured to fit on top of a top surface 110 of a bottom unit 100 for a hot melt slot die. The apparatus 300 includes a variety of extending appendages that completely cover or partially cover the aperture 111 from which hot melt glue in liquid form is pumped from a hot melt glue reservoir 120. In an embodiment, at least one of the extending appendages 312-4 includes a carved-out underside channel 312-4-1 that partially restricts but does not completely restrict the flow of glue out of slot 125 when a top plate 130 for a top unit of the slot die is pressed down onto the top surface 110 of the bottom unit 100.
The overlay 300 is adapted to be affixed to the top surface 110 of a bottom unit 100 for a slot die device or machine of a label press. Each end of the overlay 300 includes the edge extending appendages 313 to ensure the flow of hot melt adhesive does not flow out of the slot 125 in areas that are blocked by appendages 313. In between the edge extending appendages 313 are two or more additional extending appendages 312, 312-, 312-3, 312-3, and/or 312-4, which either completely block the flow of adhesive out of the slot 125 or partially restrict and reduce the flow of adhesive out of the slot. Appendage 312-4 includes channel 321-4-1 which partially restricts or reduces the flow of adhesive out of slot 125 but does not completely block the flow of adhesive.
In an embodiment, the apparatus 300 has a length that is at least equal to the length of aperture 111 of top surface 110 for the bottom unit of a slot die. The extending appendages 313, 312, 312-1, 312-2, 312-3, and 312-4 extend to at least a width necessary to cover aperture 111 in selective locations along the aperture 111. In an embodiment, a thickness of any carved-out underside channel 312-4-1 in any extending appendage 312-4 is adjusted to achieve a desired coat weight for the hot melt adhesive on a label substrate in channel areas defined along the substrate that correspond to the extending appendage 312-4 when a web of the substrate passes over or by slot 125.
In an embodiment, the web of a label substrate has a width that corresponds to the length of the slot 125 and the web defines a plurality of rolls of labels, each roll defines a plurality of individual labels. Thus, when a press is manufacturing the labels, the web is passed by or over slot 125 and varying coat weights or no coat weight of glue (i.e., no glue at all) is selectively disposed on the backside of each of labels based on apparatus 300 and the corresponding appendages 313, 312, 312-1, 312-2, 312-3, and/or 312-4. The press cuts the web into individual sheets, and each sheet is would into a roll. Furthermore, within each roll sense marks can be imaged or printed on the backside of the label substrate to delineate and separate each individual label 400 within the roll.
In an embodiment, apparatus 300 is manufactured from a sheet of metal or metal-based material. The sheet of metal is cut to a length and width that corresponds to the slot 125 and the top surface 110 of the bottom unit of a hot melt slot die. Selective portions of the cut sheet of metal are cut out to form the appendages, which selective cover portions of aperture 111313, 312, 312-1, 312-2, 312-3, and/or 312-4. Any desired appendage 312-4 is then further milled from to achieve channel 312-4-1 with a desired thickness A. Two other sheets of metal are milled for vertical wall 314 and shelf 315. Apertures or holes 311 and 316 are drilled out of the two other sheets of metal. The three sheets of custom cut and milled metal are wielded together to in the arrangement illustrated above in
The backside of the label 400 with varying coat weights of hot melt adhesive disposed thereon is shown in
The backside of the label 400 also includes second channels 402. The second channels 402 include a hot melt adhesive coat weight that is less than what would have been achieved with a flood coating of the adhesive. These are channels 402 in which an extending appendage 312-4 included a milled or underside carved-out channel 312-4-1, which restricted the flow of the hot melt adhesive exiting from slot 125 when a web of a label substrate passed by or over the slot 125 of the slot die during manufacturing of the label on a press.
Furthermore, the backside of the label 400 includes third channels 403. The third channels 403 include a full coat weight of hot melt adhesive. These are channels 403 in which there was no extending appendage completely or partially blocking the flow of adhesive out of slot 125 when a web of a label substrate passed by or over the slot 125 of the slot die during manufacturing of the label on a press.
Three of the third channels 403 are illustrated in
Each of the second channels 402 and third channels 403 are separated by a pair of first channels 401. That is, the channels 401-403 do not intersect of overlap with one another. Stated another way, the only intersection of the channels is between channels 401 and 402 along their sides or 403 and 402 along their sides.
The second channels 402 can be viewed as two sets of three of the second channels 402. Each set of second channels 402 is adjacent to a given first channel along a first side, and the given first channel 401 is further adjacent to a given third channel 403.
In an embodiment, the second channels 402 cover approximately 46.2% of a total area for the backside of the label 400 and the second channels 402 include a hot melt adhesive coat weight of 12 gsm (grams per square meter). In an embodiment, the third channels 403 cover approximately 42.8% of the total area for the backside of the label 400 and the third channels include a hot melt adhesive coat weight of 20 gsm. In an embodiment, the first areas cover approximately 11% of the total area for the backside of the label 400 and the first channels 401 are devoid of any adhesive. Thus, the second channels 402 cover more of a total area of the backside than the third channels 403 and the third channels 403 cover more of the total area then the first channels 401.
In an embodiment, the channeled pattern of varying coat weights on the backside of the label consumes glue on the corresponding press at a rate of 14 gsm. This rate of consuming glue is approximately a 20% reduction in the rate in which a conventional slot die of a press consumes glue when flood coating the glue on the backside of a label.
In an embodiment, label 400 with the varying coat weights of hot melt adhesive/glue has an 50% improvement in peel force over a conventional flood coated hot melt glue label.
In an embodiment, label 400 is a linerless label. In an embodiment, the front side of the label includes a thermally activated print/image coating, which when heat is applied by a thermal printer causes custom indicia to be imaged/printed on the front side of the label.
Notably, two edges of label 400 include a corresponding first channel 401 for which there is no adhesive on the backside of the label 400. This mitigates melting glue from seeping or oozing out sides of the label 400 when the label is used in warm or hot environments.
Notably, the second channels 402 are located in areas of the backside that are less critical, such that the reduced or less than a full coat weight of adhesive does not adversely impact performance of the label 400. The locations of the second channels 402 also prevent wrinkling in the label 400 when the label 400 is adhered to a surface, which is not the case with conventional adhesive patch pattern labels that do wrinkle. However, the reduced coat weights in the second channels 402 along with the first channels 401 where there is no adhesive reduce the amount of adhesive needed to manufacture the label 400. Accordingly, label 400 can be manufactured at a lost cost than a conventional flood coated adhesive label.
Notably, the third channels 403 are located adjacent to the two edges or sides of the label 400 and in a substantial middle of the label 400. This arrangement with a full coat weight of adhesive along the backside of the label 400 maximizes label 400 performance and results in a 20% increase in peel performance over a conventional flood coated adhesive label.
The method 500 produces apparatus 300 and when apparatus 300 is integrated into system 200 for a bottom and top unit of a slot die in a press, labels 400 are produced. Each label 400 includes varying coat weights of hot melt adhesive disposed on a backside of the corresponding label 400.
At 510, the processor of the press causes a machine to cut out an overlay from a piece of material to form an overlay for a top surface 110 of a bottom unit 100 associated with a hot melt adhesive slot die device of a label press. The overlay is the apparatus 300 discussed above. In an embodiment, the material is metal, hard heat-resistant plastic, or a composite material made of combinations of metal and/or plastics.
At 511, the processor of the press causes the machine to cut out two or more extending appendages 312, 312-1, 312-2, 313-2, 312-4, and/or 313 sized to cover portions of an aperture 111 of the top surface 110 of the bottom unit 100. Liquid hot melt adhesive is pumped up through the aperture 111 by the bottom unit 110 from a glue reservoir 120 and forced out of a slot 125 of the hot melt adhesive slot die device when a top plate 130 of a top unit is forced down onto the bottom unit 100 with the overlay (i.e., apparatus 300) in between the top surface 110 and an underside surface of a top plate 130 of the top unit.
In an embodiment, at 512, the processor of the press causes the machine to cut out an underside channel 312-4-1 in at least one of the extending appendages 312-4 by reducing a thickness of the material in areas of an underside surface corresponding to the extending appendage 312-4. The channel 312-4-1 was illustrated above in
In an embodiment, at 513, the processor of the press causes the machine to cut out a first extending appendage 312-1 or 313 with a first width and causes the machine to cut out a second extending appendage 312-3 with a second width. The first width is greater than the second width.
In an embodiment, at 514, the two or more extending appendages include a first edge extending appendage 313, a second edge extending appendage 313, and two or more additional extending appendages 312, 312-1, 312-2, 312-3, and/or 312-4 between the first edge extending appendage 313 and the second edge extending appendage 313. The edge extending appendages 313 are illustrated above in
Although the present invention is described with reference to certain preferred embodiments thereof, variations and modifications of the present invention can be affected within the spirit and scope of the following claims.
