Abstract:
According to an aspect, the present invention is directed to a method for applying a label to a substrate. The method includes applying an ink layer to a transfer mechanism; applying a binding layer to the ink layer; and contacting the binding layer to the substrate such that the binding layer and the ink layer are substantially removed from the transfer mechanism.

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
       [0001]    The present application claims the benefit of U.S. Provisional Application No. 61/924,891 filed Jan. 8, 2014, which is incorporated herein by reference in its entirety. 
     
    
     FIELD OF THE INVENTION 
       [0002]    The present invention relates generally to labels, methods of making labels, and methods of applying labels to substrates. More specifically, in some embodiments, the present invention relates to faceless labels and method of making a faceless label and the application methods of a faceless label to substrates of various shapes and sizes without the use of a paper or other material backing. 
       BACKGROUND OF THE INVENTION 
       [0003]    Currently, labels are applied to containers or bottles to provide information such as the supplied or the contents of the container. Such containers and bottles are available in a wide variety of shapes and sizes for holding many different types of materials, including detergents, chemicals, personal care products, motor oils, beverages, and others. 
       SUMMARY OF THE INVENTION 
       [0004]    According to an aspect, the present invention is directed to a method for applying a label to a substrate. The method includes applying an ink layer to a transfer mechanism; applying a binding layer to the ink layer; and contacting the binding layer to the substrate such that the binding layer and the ink layer are substantially removed from the transfer mechanism. 
         [0005]    According to another aspect, the present invention is directed to a method for applying a label to a substrate. The method includes applying a printable release layer to a transfer mechanism; applying an ink layer to the printable release layer; applying a binding layer to the ink layer; and contacting the binding layer to the substrate such that the binding layer and the ink layer are substantially removed from the transfer mechanism. 
         [0006]    The accompanying drawing, which is incorporated in and constitute a part of this specification, illustrates one or more embodiments of the invention and, together with the description, serves to explain the principles of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    A full and enabling disclosure of the present invention, including the best mode thereof directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended drawing, in which: 
           [0008]      FIG. 1  is a pictorial representation of a method in accordance with a first embodiment of the present invention; 
           [0009]      FIG. 2  is a graphical representation of the method of  FIG. 1 ; 
           [0010]      FIG. 3  is a pictorial representation of a method in accordance with a second embodiment of the present invention; 
           [0011]      FIG. 4  is a graphical representation of the method of  FIG. 3 ; 
           [0012]      FIG. 5  is a pictorial representation of a method in accordance with a third embodiment of the present invention; 
           [0013]      FIG. 6  is a graphical representation of the method of  FIG. 5 ; 
           [0014]      FIG. 7  is a pictorial representation of a method in accordance with a fourth embodiment of the present invention; 
           [0015]      FIG. 8  is a graphical representation of the method of  FIG. 7 ; 
       
    
    
       [0016]    Repeat use of reference characters in the present specification and drawings is intended to represent same or analogous features or elements of the invention. 
       DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
       [0017]    Reference will now be made in detail to presently preferred embodiments of the invention, one or more examples of which are illustrated in the accompanying drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that modifications and variations can be made in the present invention without departing from the scope or spirit thereof. For instance, features illustrated or described as part of one embodiment may be used on another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents. 
         [0018]    Embodiments of the present invention include methods for the application of labels onto substrates of various shapes and sizes. Common to the embodiments of the invention is the absence of a paper or other material backing associated with the label and its application to the substrates. In the embodiments of the present invention, due to the absence of such non-transferable component normally associated with a label, there is a reduction in the amount of waste associated with the application processes. In addition, utilizing the methods of the present invention, the application of labels to substrates of various sizes and shapes, including three-dimensional substrates, may be completed more effectively as the components of the present invention may contour to the dimensions of substrate, as more fully discussed below. 
         [0019]      FIGS. 1 and 2  illustrate a first embodiment of the present invention, as a label may be applied to a desired substrate without the use of a backing material. As common with the first through fourth embodiments described, the present invention utilizes a transfer mechanism that the components of the label are first applied to and then is used to transfer those components onto the desired substrate. As shown in  FIGS. 1 and 2 , a transfer mechanism  101  is deposited (Step  111 ) with an ink layer  102  and then a binding layer  103  is deposited (Step  112 ) on top of ink layer  102 . Ink layer  102  and/or binding layer  103  are then dried and/or cured (Step  113 ) while attached to transfer mechanism  101 , and ink layer  102  and binding layer  103  are then applied (Step  114 ) to a substrate  104  as the adhesive of binding layer  103  makes contact with substrate  104 . Transfer mechanism  101  is then returned to its starting position such that the process may be repeated (Step  115 ). 
         [0020]    As indicated above, transfer mechanism  101  of the present invention is utilized to house the components of the label (i.e., the ink layer and binding layer and possible other components, as discussed further below) prior to the components&#39; application to the particular substrate. Advantageously, the transfer mechanism may be utilized again and again thereby reducing the amount of waste typically associated with such methods. 
         [0021]    To meet the requirements of such methods, transfer mechanism  101  may be a diaphragm constructed on a moving conveyer belt or in a sheet feed system to aid in the process of the application of the necessary label components onto the substrate and then to repeat to process. In some embodiments, the conveyer belt may be continuously moving or may utilize a batch-movement process, or a semi-batch movement process, depending on the specifications of the user. 
         [0022]    Transfer mechanism  101  may be constructed of any material or materials that allow for the various label components to be transferred on and off transfer mechanism  101  and allow for transfer mechanism  101  to maintain its shape during the application of the label components but further allow flexibility to conform to the shape of the substrate. For example, if a diaphragm is used for the construction of transfer mechanism  101 , it may include a textured or matte surface to increase the ease of releasability of the label components to the substrate. In addition, in embodiments where a diaphragm is utilized, suitable materials for the construction of the belt that provide enhanced release qualities as well as the desired flexibility may include silicone, fluorinated polymers, or low surface energy polymers including polyamide, Teflon®, polyolefin, and others. Such materials may be utilized to construct the entirety of the diaphragm or may serve as coatings on the diaphragm depending on the user&#39;s specifications. Examples of suitable silicone coated release materials include, D2 CL PET 7300A/7350A, Grade 27320 and 2SLKN and 5.0 MT PET 4400/4400 Grade 26967 from Loparex LLC in Iowa City, Iowa. In addition, suitable polymer examples include, acrylic-based coatings, such as R130W from Mayzo, Inc. in Suwanee, Ga. and polypropylene based coatings, such as HFM sheets from Avery Dennison NTP in Pasadena, Calif. 
         [0023]    To ensure the proper releasability of the label components from transfer mechanism  101 , the surface energy of transfer mechanism  101  on the side that makes contact with the label components may be between about 20 mN/m and about 40 mN/m. In some embodiments, including those where silicone is utilized in the construction of transfer mechanism  101 , additional items, including corona treatment or flame treatment, may be added to transfer mechanism  101  to ensure the proper surface energy. 
         [0024]    Ink layer  102  utilized in the methods of the present invention may include ink or graphics, and may be a mono-colored or multi-colored ink layer depending on the printed message and/or the intended pictorial design. Such designs for use in connection with the present methods include serial numbers, bar codes, trademarks, etc. 
         [0025]    The present methods may utilize a variety of commercially available inks for use in ink layer  102  including UV-curable, latex, water-based, nonpolar, solvent-based, pigments, dyes, solvent-based with polar functionality, Eco-solvent, hot-solvent, solventless, 100% solid and others. Examples of these inks include Sun Sheen (a product of Sun Chemical, Inc. of Santa Fe Springs, Calif. identified as an alcohol dilutable polyamide ink), Suntex MP (a product of Sun Chemical, Inc. identified as a solvent-based ink formulated for surface printing acrylic coated substrates, PVDC coated substrates and polyolefin films), X-Cel (a product of Water Ink Technologies, Inc. of Lincolnton, N.C. identified as a water-based film ink for printing film substrates), Uvilith AR-109 Rubine Red (a product of Daw Ink, Inc. of Commerce, Calif. identified as a UV ink) and CLA91598F (a product of Sun Chemical, Inc. identified as a multibond black solvent-based ink). 
         [0026]    Ink layer  102  may range, in some embodiments, from about 0.5 to about 10 microns. In further embodiments, the thickness of ink layer  102  may range from about 1 to about 5 microns, and in other embodiments, the thickness of ink layer  102  may be about 3 microns. 
         [0027]    The application of ink layer  102  to transfer mechanism  101  may be accomplished by various methods known in the art, including inkjet printing, screen printing, or coating. In one embodiment of the invention, the ink layer may be deposited through raster graphics or bitmap imaging, which is sometimes referred to in the printing and prepress industries as contone or contone printing. In some embodiments where inkjet printing is used, a thermal inkjet printer or piezo inkjet printer may be utilized to apply ink layer  102  to transfer mechanism  101 . In such embodiments, the ink of ink layer  102  utilized in the method should be of a suitable viscosity when passing through the printhead of such printers to ensure an accurate and durable image. For example, in such embodiments, thermal inks may include a viscosity of between about 3 and about 5 mPa/s at 25° C., while piezo ink jet fluids may include a viscosity in the range of about 1 to about 30 mPa/s at 25° C. 
         [0028]    Binding layer  103  may be constructed of inkjettable adhesives to meet the demands of the method utilized. For example, binding layer  103  may be constructed of monomers, including those of acrylic, epoxy, silicone, vinyl, and olefinic based chemistries. In some embodiments, oligomers or short chain polymers may be utilized in connection with binding layer  103 . Short chain polymers that may be beneficial in connection with binding layer  103  refers to polymers where number average molecular weight (Mn) is less than the entanglement molecular weight (Me) for the respective monomeric systems. In addition, to allow such materials to consistently jet through an inkjet nozzle, the materials utilized as binding layer  103  may include a viscosity range between about 5 to about 50 cps. 
         [0029]    In embodiments of the invention where inkjettable adhesives are utilized in connection with binding layer  103 , such adhesives may be prepared using any known methods in the art including, emulsion, solvent or solvent-less polymerization techniques, where such inkjettable adhesives may be processed using a solvent, water or a heated nozzle. The user&#39;s specifications may dictate the necessary methods utilized for such preparation and processing. 
         [0030]    In some embodiments, the inkjettable adhesives utilized in connection with binding layer  103  may be based on a two-component adhesive system where a first component is jetted through a first nozzle and a crosslinking or curing agent (second component) is jetted through a second nozzle onto the first component. In such embodiments, the viscosity of both components may be maintained at a level to ensure adequate room temperature mixing through diffusion. Suitable first and second component pairs include epoxy oligomers &amp; resins and amine oligomers; epoxy oligomers &amp; resins and acid catalysts; epoxy oligomers and basic catalysts; and oligomers with isocyante functional groups and alchohols, catalysts, or moisture. 
         [0031]    In additional embodiments of the present invention utilizing the two component adhesive, one component of the two components may be coated/printed/fabricated onto the desired surface/media using additional non-jettable technique, including gravure printing, screen printing, casting, spin coating, die-coating etc. In further embodiments of the invention that utilize the two component adhesive, one of the two components may be situated in ink layer  102  to provide the same effect. 
         [0032]    In addition to those adhesives mentioned above, pressure sensitive adhesives (PSA) may be utilized in connection with binding layer  103 . PSAs are a class of adhesives characterized by low Tg and may be applied to a given surface at room temperature with the application of a small amount of pressure. Pressure sensitive adhesives are tacky at room temperature and are known to adhere to a wide variety of high and low energy surfaces. 
         [0033]    Suitable PSAs that may be used in connection with binding layer  103  include monomers, for example, 2-Ethylhexyl acrylate, Butyl acrylate that are copolymerized with certain polar monomers including acrylic acid, N-vinyl pyrrolidone or 2-Hydroxy ethyl acrylate. The polymer may then be further crosslinked using known crosslinkers and an energy source to yield a desired balance of tack and shear properties. 
         [0034]    In some embodiments, the molecular weight of the polymer utilized may be in excess of ten times the entanglement molecular weight to allow sufficient chain interactions that allow for proper viscoelastic properties of such polymers. In some embodiments, oligomers or short chain polymers that may be used in connection with a PSA of the present invention may be assembled into a polymer of sufficiently high molecular weight using a self assembly process. Such process may be completed by attaching hydrogen bonding moieties to the oligomeric chains. Suitable hydrogen bonding moieties include vinyl pyrrolidone and acrylic acid, amine functionalized chains and acrylic acid, and other hydrogen bond donors and hydrogen bond acceptors. In further embodiments, hydrogen bonding solvents such as methanol, ethanol or tetrahydrofuran may be utilized. In addition, the combination when processed at a temperature above 75° C., such hydrogen bonds will cease to exist leading to a lower viscosity and once jetted, the chains will assemble into a higher molecular weight polymer, suitable for use in the present invention, due to the aid of hydrogen bonding. 
         [0035]    As described in prior embodiments a desired two or more component adhesive could also be realized by incorporating one of the components onto the surface or media to be printed (jetted) on. As an example, an acid activated system can be achieved either by incorporating the acid sensitive polymer in the media and catalyst in the jettable pack or vice-a-versa to have the same end-effect. Examples of media and surfaces may include glass, paper, PET, PE, Aluminum etc. Additionally, one component of the two component system may be coated/printed/fabricated onto the desired surface/media using additional non-jettable technique. Examples of such techniques would include gravure printing, screen printing, casting, spin coating, die-coating etc. 
         [0036]    In some embodiments, the adhesives utilized in binding layer  103  may include additives to provide enhanced properties. For example, in some embodiments, additives comprising wetting agents, surfactants, inorganic fillers, colorants, viscosity modifiers, optical brighteners and/or others may be added. The user&#39;s specifications will dictate the necessary components utilized. 
         [0037]    As discussed above, the present method may further utilize a drying and/or curing step for any or all of the label component layers. Any such methods known in the art may be utilized to complete the drying and/or curing step depending on the particular materials utilized for ink layer  102  and binding layer  103 . For example, if the ink utilized for ink layer  102  is UV-curable, then a UV curing process would be utilized in the curing step. In some embodiments, if both drying and curing is utilized, drying through heating may be completed first and then curing may be completed through any known curing process, including heating or radiation (IR/UV), where such radiation curing may involve using a free radical photoinitiator, photo-acid based photocatalytic or a combination curing pack. 
         [0038]      FIGS. 3 and 4  illustrate a second embodiment of the present invention, where a printable release layer is utilized. The printable release layer, depending on the embodiment, may act as a release or a protective layer as more fully explained below. In the second embodiment of the present invention, transfer mechanism  501  is deposited (Step  511 ) with a printable release layer  502 , which acts to aid in the release of the other label components from transfer mechanism  501 . Following the addition of printable release layer  502 , an ink layer  503  is deposited (Step  512 ) onto printable release layer  502 . A binding layer  504  is then applied (Step  513 ) to ink layer  503 . The layers  502 ,  503 , and  504  may then be dried and/or cured (Step  514 ) as necessary. Following curing, ink layer  503  and binding layer  504  are then transferred (Step  515 ) to substrate  505 , while printable release layer  502  remains on transfer mechanism  501  as it provides qualities to release layers  503  and  504 . In such embodiments, prior to the repeat of the process, transfer mechanism  501  may be cleaned (Step  516 ) with a suitable material as discussed below. Following the cleaning of transfer mechanism  501 , the process may be repeated (Step  517 ). In such embodiments of the present invention, depending on the particular item utilized as printable release layer  502 , an initial deposit of printable release layer  502  may only be necessary at the outset, whereas in other embodiments, printable release layer  502  may be applied each time. 
         [0039]    Transfer mechanism  501 , ink layer  503 , and binding layer  504 , of the second embodiment may be the same as those described above with respect to the first embodiment. 
         [0040]    As indicated above, printable release layer  502  of the second embodiment acts as a release material to aid in the transfer of ink layer  503  and binding layer  504  from transfer mechanism  501  to substrate  505 . Accordingly, printable release layer  502  may be constructed of materials that provide such releasability, similar to those described with respect to transfer mechanism  101  in the first embodiment. 
         [0041]    When a printable release layer is present, it may have a single layer or a multilayered structure. The thickness of the printable release layer may be in the range of about 12.5 to about 125 microns, and in one embodiment from about 25 to about 75 microns. Examples of printable release layers that may be used in connection with the present invention are described in U.S. Pat. No. 6,106,982, the entirety of which is incorporated by reference. 
         [0042]    Printable release layer  502  may comprise polyolefins, thermoplastic polymers of ethylene and propylene, polyesters, polyurethanes, polyacryls, polymethacryls, epoxy, vinyl acetate homopolymers, co- or terpolymers, ionomers, antioxidants, inorganic colloidal silica or alumina binder, and mixtures thereof. To ensure the proper releasability of ink layer  503  and binding layer  504  from printable release layer  502 , the surface energy of printable release layer that makes contact with ink layer  503  may be between about 20 mN/m and about 35 mN/m. In some embodiments, including those where silicone is utilized in the construction of printable release layer  502 , additional items, including corona treatment or flame treatment, may be added to printable release layer  502  to ensure the proper surface energy. 
         [0043]    As indicated above, following the transfer of ink layer  503  and binding layer  504  onto substrate  505 , transfer mechanism  501  is cleaned. Such cleaning process may remove excess ink and/or adhesive that remains on transfer mechanism  501  following the transfer to the substrate. The cleaning process may be necessary to ensure that a new print layer that is deposited during the present method is not affected by components that may still be on transfer mechanism  501 , thereby altering the aesthetic or functional qualities of ink layer  503 . Any known method for cleaning transfer mechanism  501  may be utilized, for example, an adhesive plate may be used to make contact with transfer mechanism  501  and remove any undesired remaining components. 
         [0044]      FIGS. 5 and 6  illustrate a third embodiment of the present invention. In the third embodiment, printable release layer  702  may be released from transfer mechanism  701  and onto the desired substrate  705  to provide a protective barrier to the ink and adhesive. During the application process, transfer mechanism is deposited (Step  711 ) with printable release layer  702 . Following the application of printable release layer  702 , ink layer  703  is deposited (Step  712 ) onto printable release layer  702 . Then, binding layer  704  is deposited (Step  713 ) onto ink layer  703 , where the layers  702 ,  703 , and  704  may be dried and/or cured (Step  714 ) depending on the particular items utilized. After curing, layers  702 ,  703 , and  704  may be applied (Step  715 ) to the substrate  705 , and then the process may be repeated (Step  716 ). The third embodiment allows for the cleaning step of the above-described embodiment to be omitted. Such reduction in method steps likely reduces the costs of production of labels for application to substrates. 
         [0045]    As indicated above, printable release layer  702  may provide desirable properties to the other label components before and after the label components are affixed to a substrate. The presence of a transparent printable release layer over the ink layer  703  may, in some embodiments provide additional properties such as antistatic properties stiffness and/or weatherability, and printable release layer  702  may protect ink layer  703  from, e.g., weather, sun, abrasion, moisture, water, etc. Printable release layer  702  may enhance the properties of the underlying ink layer  703  to provide a glossier and richer image. Printable release layer  702  may also be designed to be abrasion resistant, radiation resistant (e.g, UV), chemically resistant and/or thermally resistant thereby protecting the label components and, particularly ink layer  703  from degradation from such causes. Printable release layer  702  may also contain antistatic agents, or anti-block agents to provide for easier handling when the labels are being applied to containers at high speeds. 
         [0046]    Printable release layer  702  may further contain UV light absorbers and/or other light stabilizers. Among the UV light absorbers that may be useful are the hindered amine absorbers available from Ciba Specialty Chemical Co. of Basel, Switzerland under the trade designations Tinuvin 111, Tinuvin 123, (bis-(1-octyloxy-2,2,6,6-tetramethyl-4-piperidinyl) sebacate; Tinuvin 622, (a dimethyl succinate polymer with 4-hydroxy-2,2,6,6-tetramethyl-1-piperidniethanol); Tinuvin 770 (bis-(2,2,6,6-tetramethyl-4-piperidinyl)-sebacate); and Tinuvin 783. Additional light stabilizers include the hindered amine light stabilizers available from Ciba Specialty Chemical Co. under the trade designation “Chemassorb”, especially Chemassorb 119 and Chemassorb 944. The concentration of the UV light absorber and/or light stabilizer is in the range of up to about 2.5% by weight, and in one embodiment about 0.05% to about 1% by weight. 
         [0047]    In some embodiments, printable release layer  702  may also contain an antioxidant. Any antioxidant useful in making thermoplastic films may be used. These include the hindered phenols and the organo phosphites. Examples include those available from Ciba Specialty Chemical Co. under the trade designations Irganox 1010, Irganox 1076 or Irgafos 168. The concentration of the antioxidant in the thermoplastic film composition may be in the range of up to about 2.5% by weight, and in one embodiment about 0.05% to about 1% by weight. 
         [0048]    In the embodiment illustrated in  FIGS. 7 and 8 , the invention utilizes a flood technique that allows for the addition of an excess of a printable release layer  902  onto a transfer mechanism  901 . In the embodiment, transfer mechanism  901  is deposited (Step  911 ) with a printable release layer  902 . As indicated above, printable release layer  902  provides an amount of printable release layer material to sufficiently cover transfer mechanism. Following the addition of printable release layer  902 , ink layer  903  is deposited (Step  912 ) onto printable release layer  902 . In addition, binding layer  904  is deposited (Step  913 ) onto ink layer  903 . In some embodiments, an ink layer and a binding layer may not completely cover a printable release layer. As indicated above, this may be done to ensure that an ink layer and a binding layer are sufficiently covered when the label is transferred to a substrate. In instances when a printable release layer is only applied to a portion of transfer mechanism, it may not sufficiently transfer to a substrate, thereby leaving the label with less than ideal protective qualities as desired. 
         [0049]    Following the addition of layers  902 ,  903 , and  904 , the layers may be dried and/or cured (Step  914 ) as necessary. The layers  902 ,  903 , and  904  may then be transferred (Step  915 ) to substrate  905 . In addition, due to the remaining printable release layer following Step  915 , transfer mechanism  901  may be cleaned (Step  916 ) prior to the repeat of the process (Step  917 ). 
         [0050]    By way of further example, unlike the earlier described embodiments, a fifth embodiment may utilize a transfer sheet that may be dissolved by water or a solvent. For each transfer, a transfer sheet, which may be picked up from a stack of such sheets, ink layer and binding layer may be deposited onto the surface of the transfer sheet, ink layer and binding layer may be optionally cured, and ink layer and binding layer may be transferred to the substrates. In one embodiment of the invention, the transfer sheet may be made of water soluble or solvent soluble materials. Upon finishing of the transfer process, the transfer sheet may be washed away by the dissolving solvent or water. The transfer sheet may be transferred with the ink layer and binding layer onto the substrate before being washed away, or the transfer sheet may stay behind on a transport mechanism, such as a belt or diaphragm. Water soluble materials suitable for use as the transfer sheet include rice paper, polyvinyl alcohol (PVAc), ethylene vinyl alcohol (EVOH), starch and its derivatives, cellulose and its derivatives such as cellulose ethers, ethylcellulose polymers and other soluble materials. 
         [0051]    In this exemplary fifth embodiment, a transfer sheet may be transferred to meet with a substrate on a moving belt. Due to the washing process, the moving belt may be constructed of a diaphragm with a plurality of orifices where heat may exit to aid in the washing process. In other embodiments, the moving belt may be constructed of a diaphragm without orifices, but that can be heated and wetted by known methods to also aid in the washing process. 
         [0052]    In some embodiments, the ink layer and the binding layer may be formulated into one single layer. This formulation may contain colorants and also adhesive components. The ink and binding layer may be first deposited onto the transfer mechanism, optionally dried and or cured, and then applied to a substrate to be labeled. 
         [0053]    In some embodiments of the invention, the components of the various ink layers, binding layers and printable release layers described above may be combined into a single layer. In such embodiments, the combination of all materials together may limit the amount of stages necessary for the creation of the labels. 
         [0054]    These and other modifications and variations to the present invention may be practiced by those of ordinary skill in the art, without departing from the spirit and scope of the present invention, which is more particularly set forth in the appended claims. In addition, it should be understood that aspects of the various embodiments may be interchanged in whole or in part. Furthermore, those of ordinary skill in the art will appreciate that the foregoing description is by way of example only, and is not intended to limit the invention so further described in such appended claims. Therefore, the spirit and scope of the appended claims should not be limited to the description of the versions contained therein.