Printing system and method involving multi-layer films

Abstract

Embodiments of the present disclosure relate to printing systems and methods that may include an ink composition and a multilayer film, the ink composition comprising charged ink particles dispersed in a hydrocarbon liquid. The multilayer film may include a polymer core layer; and one or more printed layers adjacent to the polymer core layer. The one or more printed layers may include at least 50 wt.% of an ethylene vinyl acetate copolymer having acid and acrylate functional groups. Based on the total weight of the ethylene vinyl acetate copolymer having acid and acrylate functional groups, the ethylene vinyl acetate copolymer having acid and acrylate functional groups may include 0.5 wt.% to 4 wt.% of methacrylic acid or acrylic acid, 0.5 wt.% to 4 wt.% of an acrylate, 7 wt.% to 40 wt.% of vinyl acetate, and the balance ethylene.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to U.S. Provisional Application No. 62 / 842,012, filed May 2, 2019, the entire disclosure of which is hereby incorporated by reference. Technical Field

[0003] The embodiments described herein relate generally to multilayer films, and particularly to multilayer films for use in digital printing systems. Background Art

[0004] In recent years, digital press printing processes have impacted the graphic arts market. In conventional printing methods using fixed etching plates, ink is attracted to the substrate by physically transferring the ink from an ink tray to a roller. In digital press printing, the ink composition is attracted to the photo imaging plate by an electrical charge, rather than by physical transfer from an ink tray to a roller. Summary of the Invention

[0005] Digital printing processes use an ink composition containing an ethylene and acrylic acid copolymer, which is heated and applied to a substrate such as a flexible film. Like conventional printing presses, digital printing processes use liquid ink to print images. However, in digital printing processes, the ink contains charged particles that are attracted to the electrostatic field formed on a photo imaging plate. Once the ink composition is placed on the photo imaging plate, it is directly transferred to the heated blanket through direct contact between the heated blanket and the ink composition on the photo imaging plate. On the heated blanket, the ink particles of the ink composition melt into a smooth ink film, which is then transferred to the substrate.

[0006] Conventional digital press printing processes utilize overprint varnishes (OPVs) or lamination processes to protect the printed material (the transferred ink film) on the final packaging structure. Furthermore, conventional digital press printing processes often require the application of a primer on top of the corona-treated film to provide proper wettability and anchor the printed artwork. When the packaging design requires an inside / outside (lap seal) seal, the use of such primers presents disadvantages, including increased process complexity, increased costs associated with the process, and poor sealing.

[0007] Therefore, there is a need for a printing system utilizing a multilayer film that achieves proper wetting and anchoring of the ink composition without requiring an additional primer layer or corona or plasma treatment. Embodiments of the present disclosure address these needs by providing a multilayer film comprising an ink anchoring layer ("print layer") that is capable of properly wetting and anchoring the ink composition during the digital printing process. The multilayer film also comprises a core layer that can impart the multilayer film with adequate stiffness so that the film can be printed with adequate dimensional retention when using a digital printing press line.

[0008] According to at least one embodiment of the present disclosure, a printing system is provided. Embodiments of the printing system may include an ink composition and a multilayer film, wherein the ink composition includes charged ink particles dispersed in a liquid. The multilayer film may include a polymer core layer; and one or more printed layers adjacent to the polymer core layer. The one or more printed layers may include at least 50 wt.% of an ethylene-vinyl acetate copolymer having acid and acrylate functional groups. Based on the total weight of the ethylene-vinyl acetate copolymer having acid and acrylate functional groups, the ethylene-vinyl acetate copolymer having acid and acrylate functional groups may include 0.5 wt.% to 4 wt.% of methacrylic acid or acrylic acid, 0.5 wt.% to 4 wt.% of an acrylate, 7 wt.% to 40 wt.% of vinyl acetate, and the balance ethylene.

[0009] According to at least one embodiment of the present disclosure, a printing method is provided. An embodiment of the printing method may include transferring an ink composition onto a printed layer of a multilayer film. The ink composition may include charged ink particles dispersed in a liquid. The multilayer film includes: a polymer core layer and one or more printed layers adjacent to the polymer core layer, the one or more printed layers including at least 50 wt.% of an ethylene vinyl acetate copolymer having acid and acrylate functional groups; and wherein, based on the total weight of the ethylene vinyl acetate copolymer having acid and acrylate functional groups, the ethylene vinyl acetate copolymer having acid and acrylate functional groups includes 0.5 wt.% to 4 wt.% of methacrylic acid or acrylic acid, 0.5 wt.% to 4 wt.% of acrylate, 7 wt.% to 40 wt.% of vinyl acetate, and the balance ethylene.

[0010] Thus, embodiments of the present disclosure can provide printing systems and methods that can achieve proper wetting and anchoring of ink compositions during a digital printing process without the need for additional primer layers or corona or plasma treatments.

[0011] These and other embodiments are described in further detail in the detailed description which follows. DETAILED DESCRIPTION

[0012] Specific embodiments of the present application will now be described. These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the subject matter to those skilled in the art.

[0013] The term "polymer" refers to a polymeric compound prepared by polymerizing monomers of the same or different types. Thus, the general term polymer encompasses the term "homopolymer," which generally refers to a polymer prepared from only one type of monomer, and "copolymer," which refers to a polymer prepared from two or more different monomers. As used herein, the term "interpolymer" refers to a polymer prepared by polymerizing at least two different types of monomers. Thus, the general term interpolymer encompasses copolymers or polymers prepared from two or more different types of monomers, such as terpolymers.

[0014] As used herein, "acid copolymer" can be a direct copolymer or a graft copolymer. The term "direct copolymer" can refer to a copolymer made by polymerizing monomers together at the same time, as opposed to a graft copolymer where monomers are polymerized on an existing polymer chain.

[0015] "Polyethylene" or "ethylene-based polymer" shall mean a polymer comprising greater than 50 mole percent of units derived from ethylene monomer. This includes ethylene-based homopolymers or copolymers (meaning units derived from two or more comonomers). Common forms of ethylene-based polymers known in the art include, but are not limited to: low density polyethylene (LDPE); linear low density polyethylene (LLDPE); ultra low density polyethylene (ULDPE); very low density polyethylene (VLDPE); single-site catalyzed linear low density polyethylene, which includes both linear low density resins and substantially linear low density resins (m-LLDPE); medium density polyethylene (MDPE); and high density polyethylene (HDPE). Ethylene copolymers can be produced by methods well known in the polymer art using autoclave or tubular reactors. The copolymerization can be carried out as a continuous process in an autoclave as disclosed in US Pat. Nos. 3,264,272; 4,351,931; 4,248,990; and 5,028,674 and in International Patent Application WO 99 / 25742.

[0016] Ethylene vinyl acetate (EVA) is a copolymer of ethylene and vinyl acetate: Examples of EVA copolymers are available from several sources, including DuPont Company, Wilmington, Del.

[0017] Ethylene / acid copolymers and methods for their preparation are well known in the art and are disclosed, for example, in U.S. Patent Nos. 3,264,272; 3,404,134; 3,355,319; and 4,321,337. Commercial acid copolymers suitable for use in the present invention are available from various sources, including DuPont de Nemours and Company, Wilmington, Delaware.

[0018] The term "LDPE" may also be referred to as "high pressure ethylene polymer" or "highly branched polyethylene" and is defined to mean a polymer that is partially or completely homopolymerized or copolymerized in an autoclave or tubular reactor at pressures greater than 14,500 psi (100 MPa) using a free radical initiator such as a peroxide (see, for example, U.S. Patent No. 4,599,392, which is incorporated herein by reference). The density of LDPE resins typically ranges from 0.916 to 0.940 g / cc.

[0019] The term "LLDPE" includes resins made using a Ziegler-Natta catalyst system and resins made using single-site catalysts, including but not limited to dimetallocene catalysts (sometimes referred to as "m-LLDPE"), phosphinimines, constrained geometry catalysts, and resins made using post-metallocene molecular catalysts, including but not limited to bis(biphenylphenoxy) catalysts (also known as polyvalent aryloxyether catalysts). LLDPE includes linear, substantially linear, or heterogeneous ethylene-based copolymers or homopolymers. LLDPE contains less long chain branching than LDPE and includes: substantially linear ethylene polymers, the substantially linear ethylene polymers further defined in U.S. Patent No. 5,272,236, U.S. Patent No. 5,278,272, U.S. Patent No. 5,582,923 and U.S. Patent No. 5,733,155; homogeneously branched linear ethylene polymer compositions, such as those in U.S. Patent No. 3,645,992; heterogeneously branched ethylene polymers, such as those prepared according to the process disclosed in U.S. Patent No. 4,076,698; and blends thereof (such as those disclosed in U.S. Patent No. 3,914,342 and U.S. Patent No. 5,854,045). LLDPE resins can be prepared by gas phase, solution phase or slurry polymerization, or any combination thereof, using any type of reactor or reactor configuration known in the art.

[0020] "Multilayer structure" means any structure having more than one layer. For example, a multilayer structure (e.g., a film) can have two, three, four, five, or more layers. A multilayer structure can be described as having layers represented by letters. For example, a three-layer structure designated as A / B / C can have a core layer B and two outer layers A and C. Similarly, a structure having two core layers B and C and two outer layers A and D is represented as A / B / C / D. In some embodiments, the multilayer film of the present disclosure includes at least 2 layers. In some embodiments, the multilayer film of the present disclosure includes up to 15 layers.

[0021] Reference will now be made in detail to embodiments of the printing system.As previously stated, embodiments of the printing system described herein may include an ink composition and a multilayer film.

[0022] Reference will now be made in detail to embodiments of ink compositions for printing systems. The ink compositions may comprise charged ink particles dispersed in a liquid. Without wishing to be bound by theory, the particles of the ink composition may be charged such that they are attracted to an electrostatic field formed on a photo imaging plate during the digital printing process. The attraction of the charged particles to the electrostatic field may allow the ink composition to be precisely placed on the photo imaging plate and then transferred to a substrate, such as the embodiments of the multilayer film described herein.

[0023] The charged ink particles may include one or more pigments and a resin material. The resin material may include a fluoropolymer resin. The ink composition may include from about 0.001 wt.% to about 2 wt.%, or from about 0.001 wt.% to about 1 wt.%, of the fluoropolymer resin, based on the total weight of the ink composition. The one or more pigments of the charged ink particles may include pigments known in the art of digital printing. The ink composition may include from about 0.001 wt.% to about 5 wt.%, or from about 0.001 wt.% to about 2.5 wt.%, of the one or more pigments, based on the total weight of the ink composition.

[0024] As previously described, the charged ink particles can be dispersed in a liquid. The liquid can also be referred to as a "carrier liquid." In embodiments, the charged ink particles can be completely encapsulated within the liquid. In some embodiments, the liquid can be a hydrocarbon liquid. In other embodiments, the hydrocarbon liquid can include a petroleum hydrocarbon. The ink composition can include about 90 wt.% or less than about 80 wt.% of the liquid, based on the total weight of the ink composition.

[0025] Reference will now be made in detail to an embodiment of a multilayer film for a printing system. The multilayer film may comprise a polymer core layer; and one or more printed layers adjacent to the polymer core layer. Without wishing to be bound by theory, it is believed that the one or more printed layers of the multilayer film may allow for proper wetting and anchoring of the ink composition during the digital printing process without requiring an additional primer layer or corona or plasma treatment. Without wishing to be bound by theory, it is believed that the polymer core layer of the multilayer film may provide suitable stiffness, allowing the multilayer film to be printed with adequate dimensional retention on a digital printing press line.

[0026] In one or more embodiments, the multilayer film may comprise at least 2 layers. In some embodiments, the multilayer film of the present disclosure comprises up to 15 layers. In further embodiments, the multilayer film may comprise 2 to 15 layers, 2 to 10 layers, 2 to 5 layers, 5 to 15 layers, 5 to 10 layers, or 10 to 15 layers.

[0027] In further embodiments, the multilayer film may be a two-layer structure designated A / B, wherein the printed layer may be designated A and the polymer core layer may be designated B. In other embodiments, the multilayer film may be a three-layer structure designated A / B / C, wherein the polymer core layer may be designated B and the printed layers may be designated A and C.

[0028] As previously described, embodiments of the multilayer film may comprise a polymer core layer. In some embodiments, the polymer core layer may comprise one or more of polyethylene terephthalate, polyamide, ethylene-based polymer, propylene-based polymer, or a combination thereof. In embodiments, the polymer core layer comprises an ethylene-based polymer. In some embodiments, the polymer core layer may comprise greater than 50 mole percent of units derived from ethylene monomers. In further embodiments, the polymer core layer may comprise an ethylene-based homopolymer or copolymer. Embodiments of the polymer core layer may include, but are not limited to, low density polyethylene (LDPE); linear low density polyethylene (LLDPE); ultra low density polyethylene (ULDPE); very low density polyethylene (VLDPE); single-site catalyzed linear low density polyethylene, which comprises both linear low density resins and substantially linear low density resins (m-LLDPE); medium density polyethylene (MDPE); and high density polyethylene (HDPE).

[0029] In embodiments, the polymeric core layer may comprise an ethylene-based polymer having a 2% secant modulus greater than about 150 MPa. In some embodiments, the polymeric core layer may comprise an ethylene-based polymer having a 2% secant modulus of about 150 MPa to about 1500 MPa. In other embodiments, the polymer core layer may comprise an ethylene-based polymer having a 2% secant modulus of about 150 MPa to about 1000 MPa, about 150 MPa to about 750 MPa, about 150 MPa to about 500 MPa, about 150 MPa to about 250 MPa, about 250 MPa to about 1500 MPa, about 250 MPa to about 1000 MPa, about 250 MPa to about 750 MPa, about 250 MPa to about 500 MPa, about 500 MPa to about 1500 MPa, about 500 MPa to about 1000 MPa, about 500 to about 750 MPa, about 750 MPa to about 1500 MPa, about 750 MPa to about 1000 MPa, or about 1000 MPa to about 1500 MPa. Without wishing to be bound by theory, it is believed that the stiffness of the polymer core layer may allow for dimensional stability during the digital printing process.

[0030] In some embodiments, the polymer core layer may have a density of about 0.865 grams per cubic centimeter (g / cm 3 ) to about 0.965g / cm 3 In some embodiments, the density of the polymer core layer can be about 0.865 g / cm 3 To about 0.945g / cm 3 , about 0.865g / cm 3 To about 0.925g / cm 3 , about 0.865g / cm 3 To about 0.905g / cm 3 , about 0.865g / cm 3 To about 0.885g / cm 3 , about 0.885g / cm 3 To about 0.965g / cm 3 , about 0.885g / cm 3 To about 0.945g / cm 3 , about 0.885g / cm 3 To about 0.925g / cm 3 , about 0.885g / cm 3 To about 0.905g / cm 3 , about 0.905g / cm 3 To about 0.965g / cm 3 , about 0.905g / cm 3 To about 0.945g / cm3 , about 0.905g / cm 3 To about 0.925g / cm 3 , about 0.925g / cm 3 To about 0.965g / cm 3 , about 0.925g / cm 3 To about 0.945g / cm 3 or about 0.945 g / cm 3 To about 0.965g / cm 3 .

[0031] The polymer core layer has a melt flow rate of about 0.1 grams per 10 minutes (0.1 g / 10 min) to about 45.0 g / 10 min when measured according to ASTM D1238 at 190° C. and 2.16 kg. In some embodiments, the polymer core layer may have a melt flow rate of about 0.2 g / 10 min to about 40.0 g / 10 min, about 0.2 g / 10 min to about 30.0 g / 10 min, about 0.2 g / 10 min to about 20.0 g / 10 min, about 0.2 g / 10 min to about 10.0 g / 10 min, about 0.2 g / 10 min to about 1.0 g / 10 min, about 1.0 g / 10 min to about 45.0 g / 10 min, about 1.0 g / 10 min to about 30.0 g / 10 min, about 1.0 g / 10 min to about 20.0 g / 10 min, about 1.0 g / 10 min to about 10.0 g / 10 min, about 1.0 g / 10 min to about 5.0 g / 10 min, about 10 g / 10 min to about 45.0 g / 10 min, about 10.0 g / 10 min to about 20.0 g / 10 min, about 10.0 g / 10 min to about 15.0 g / 10 min, about 15.0 g / 10 min to about 40.0 g / 10 min, or about 15.0 g / 10 min to about 20.0 g / 10 min.

[0032] Various commercial embodiments are considered suitable for the polymer core layer. For example, a suitable polymer core layer may comprise a polymer available from The Dow Chemical Company under the trademark DOWLEX. TM GM 8070 is a commercially available linear low density ethylene based polymer.

[0033] In some embodiments, the polymer core layer can have a thickness of about 10 microns to about 445 microns. In other embodiments, the polymer core layer can have a thickness of about 10 microns (micrometers) to about 400 microns, about 10 microns to about 300 microns, about 10 microns to about 200 microns, about 10 microns to about 100 microns, about 100 microns to about 445 microns, about 100 microns to about 400 microns, about 100 microns to about 300 microns, about 100 microns to about 200 microns, about 200 microns to about 445 microns, about 200 microns to about 400 microns, about 200 microns to about 300 microns, about 300 microns to about 445 microns, about 300 microns to about 400 microns, or about 400 microns to about 445 microns.

[0034] Reference will now be made in detail to embodiments of one or more printed layers of the multilayer film described herein. As previously stated, without being bound by theory, it is believed that the one or more printed layers of the multilayer film can allow for proper wetting and anchoring of the ink composition during the digital printing process without the need for an additional primer layer or corona or plasma treatment.

[0035] In an embodiment, the one or more printed layers comprise an ethylene vinyl acetate copolymer having acid and acrylate functional groups. The ethylene vinyl acetate copolymer having acid and acrylate functional groups can be produced directly by copolymerization of ethylene with vinyl acetate, acrylate, and acid comonomers, or by blending two or more copolymers or terpolymers, by grafting, or other methods known in the art. In some embodiments, the acid and acrylate functional groups can be grafted onto the ethylene vinyl acetate polymer backbone. In other embodiments, the acid and acrylate functional groups can be achieved by blending the ethylene vinyl acetate polymer with one or more polymers having acid groups, acrylate groups, or both. In yet other embodiments, the ethylene vinyl acetate copolymer having acid and acrylate functional groups can be produced by melt blending the ethylene vinyl acetate polymer with an ethylene copolymer or terpolymer having acid groups, acrylate groups, or both. In one embodiment, the ethylene vinyl acetate polymer can be blended with an ethylene (C3-C10) alkyl acrylate copolymer and an ethylene monocarboxylic acid copolymer, wherein the monocarboxylic acid can comprise acrylic acid or methacrylic acid. In another embodiment, ethylene vinyl acetate can be blended with an ethylene alkyl acrylate monocarboxylic acid terpolymer. In one embodiment, the ethylene alkyl acrylate monocarboxylic acid terpolymer comprises an ethylene isobutyl acrylate methacrylate terpolymer. The melt index of the ethylene vinyl acetate polymer can be from about 0.5 g / 10 min to about 10 g / 10 min, from about 1 g / 10 min to about 10 g / 10 min, from about 2 g / 10 min to about 10 g / 10 min, or from about 5 g / 10 min to about 10 g / 10 min, when measured according to ASTM D1238 at 190° C. and 2.16 kg. The ethylene alkyl acrylate copolymer or terpolymer can have a melt index of about 0.5 g / 10 min to about 15 g / 10 min, about 1 g / 10 min to about 15 g / 10 min, about 5 g / 10 min to about 15 g / 10 min, or about 10 g / 10 min to about 15 g / 10 min, when measured according to ASTM D1238 at 190°C and 2.16 kg.

[0036] Without wishing to be bound by theory, it is believed that the acid- and acrylate-functional ethylene vinyl acetate copolymer can allow for proper wetting and anchoring of the ink composition during the digital printing process without the need for an additional primer layer or corona or plasma treatment. In an embodiment, the acid- and acrylate-functional ethylene vinyl acetate copolymer can comprise from about 0.5 wt.% to about 4 wt.% of methacrylic acid or acrylic acid, from about 0.5 wt.% to about 4 wt.% of acrylate, from about 10 wt.% to about 40 wt.% of vinyl acetate, and the balance ethylene, based on the total weight of the acid- and acrylate-functional ethylene vinyl acetate copolymer.

[0037] Based on the total weight of the ethylene vinyl acetate copolymer having acid and acrylate functional groups, in some embodiments, the ethylene vinyl acetate copolymer having acid and acrylate functional groups can include about 0.5 wt.% to about 4 wt.% methacrylic acid or acrylic acid or about 0.5 wt.% to about 3 wt.%, about 0.5 wt.% to about 2 wt.%, about 0.5 wt.% to about 1 wt.%, about 1 wt.% to about 4 wt.%, about 1 wt.% to about 3 wt.%, about 1 wt.% to about 2 wt.%, about 2 wt.% to about 4 wt.%, or about 3 wt.% to about 4 wt.% methacrylic acid or acrylic acid.

[0038] In an embodiment, the acrylic acid ester of the ethylene vinyl acetate copolymer having acid and acrylate functional groups may comprise an alkyl acrylate having 1 to 4 carbon atoms in the alkyl portion. In another embodiment, the acrylic acid ester may comprise methyl acrylate, ethyl acrylate, n-propyl acrylate, isopropyl acrylate, n-butyl acrylate, and isobutyl acrylate. In other embodiments, the acrylic acid ester of the ethylene vinyl acetate copolymer having acid and acrylate functional groups may comprise an alkyl ester of methacrylic acid such as methyl methacrylate, ethyl methacrylate, propyl methacrylate, n-butyl methacrylate, n-hexyl methacrylate, 2-ethylhexyl methacrylate, n-octyl methacrylate, n-decyl methacrylate, and dodecyl methacrylate. Based on the total weight of the ethylene vinyl acetate copolymer having acid and acrylate functional groups, in some embodiments, the ethylene vinyl acetate copolymer having acid and acrylate functional groups can include about 0.5 wt.% to about 4 wt.% acrylate or about 0.5 wt.% to about 3 wt.%, about 0.5 wt.% to about 2 wt.%, about 0.5 wt.% to about 1 wt.%, about 1 wt.% to about 4 wt.%, about 1 wt.% to about 3 wt.%, about 1 wt.% to about 2 wt.%, about 2 wt.% to about 4 wt.%, or about 3 wt.% to about 4 wt.% acrylate.

[0039] Based on the total weight of the ethylene vinyl acetate copolymer having acid and acrylate functional groups, in some embodiments, the ethylene vinyl acetate copolymer having acid and acrylate functional groups can contain about 7 wt.% to about 40 wt.% vinyl acetate, or about 7 wt.% to about 30 wt.%, about 7 wt.% to about 20 wt.%, about 7 wt.% to about 10 wt.%, about 10 wt.% to about 40 wt.%; about 10 wt.% to about 30 wt.%, about 10 wt.% to about 20 wt.%, about 20 wt.% to about 40 wt.%, about 20 wt.% to about 30 wt.%, or about 30 wt.% to about 40 wt.% vinyl acetate.

[0040] The density of ethylene vinyl acetate copolymer having acid and acrylate functional groups may be about 0.890 grams per cubic centimeter (g / cm 3 ) to about 0.985g / cm 3 In some embodiments, the density of the ethylene vinyl acetate copolymer having acid and acrylate functional groups may be about 0.890 g / cm 3 To about 0.980g / cm 3 , about 0.890g / cm 3 To about 0.960g / cm 3 , about 0.890g / cm 3 To about 0.940g / cm 3 , about 0.890g / cm 3 To about 0.920g / cm 3 , about 0.890g / cm 3 To about 0.900g / cm 3 , about 0.900g / cm 3 To about 0.985g / cm 3 , about 0.900g / cm 3 To about 0.960g / cm 3 , about 0.900g / cm 3 To about 0.940g / cm 3 , about 0.900g / cm 3 To about 0.920g / cm 3 , about 0.920g / cm 3 To about 0.985g / cm 3 , about 0.920g / cm 3 To about 0.960g / cm 3 , about 0.920g / cm 3 To about 0.940g / cm 3 , about 0.940g / cm 3 To about 0.985g / cm 3 , about 0.940g / cm 3 To about 0.960g / cm 3 or about 0.960g / cm 3 To about 0.985g / cm 3 .

[0041] The melt flow rate of the ethylene vinyl acetate copolymer having acid and acrylate functional groups can be from about 0.5 grams per 10 minutes (0.5 g / 10 min) to about 20.0 g / 10 min when measured according to ASTM D1238 at 190° C. and 2.16 kg. In some embodiments, the melt flow rate of the ethylene vinyl acetate copolymer having acid and acrylate functional groups can be from about 0.5 g / 10 min to about 20 g / 10 min, from about 0.5 g / 10 min to about 15.0 g / 10 min, from about 0.5 g / 10 min to about 10.0 g / 10 min, from about 0.5 g / 10 min to about 5.0 g / 10 min, from about 0.5 g / 10 min to about 1.0 g / 10 min, from about 1.0 g / 10 min to about 20 g / 10 min, from about 1.0 g / 10 min to about 15.0 g / 10 min, 10 minutes, about 1.0 g / 10 minutes to about 10.0 g / 10 minutes, about 1.0 g / 10 minutes to about 5.0 g / 10 minutes, about 5.0 g / 10 minutes to about 20.0 g / 10 minutes, about 5.0 g / 10 minutes to about 15.0 g / 10 minutes, about 5.0 g / 10 minutes to about 10.0 g / 10 minutes, about 10.0 g / 10 minutes to about 20.0 g / 10 minutes, about 10.0 g / 10 minutes to about 15.0 g / 10 minutes, or about 15.0 g / 10 minutes to about 20.0 g / 10 minutes.

[0042] In some embodiments, the one or more printed layers may comprise a blend of a polyolefin and an ethylene vinyl acetate copolymer having acid and acrylate functional groups. In embodiments, the one or more printed layers may comprise at least 50 wt.% of the ethylene vinyl acetate copolymer having acid and acrylate functional groups, based on the total weight of the one or more printed layers. Without being bound by theory, it is believed that the polyolefin and the functionalized ethylene polymer may be immiscible and may form separate phases when blended. By including at least 50 wt.% of the ethylene vinyl acetate copolymer having acid and acrylate functional groups in the one or more printed layers, the ethylene vinyl acetate copolymer having acid and acrylate functional groups may be a continuous phase in the blend, which may allow the digital ink composition to properly wet or anchor to the one or more printed layers. In some embodiments, the one or more printed layers may comprise about 50 wt.% to about 100 wt.%, about 50 wt.% to about 80 wt.%, about 50 wt.% to about 60 wt.%, about 60 wt.% to about 100 wt.%, about 60 wt.% to about 80 wt.%, about 80 wt.% to about 100 wt.% of ethylene vinyl acetate copolymer having acid and acrylate functional groups.

[0043] In embodiments of the one or more printed layers comprising a blend of a polyolefin and an ethylene vinyl acetate copolymer having acid and acrylate functional groups, the polyolefin blended with the ethylene vinyl acetate copolymer having acid and acrylate functional groups can be prepared using a homogeneous or heterogeneous catalyst system and various commercial polymerization processes known in the art. In embodiments, the density of the polyolefin blended with the ethylene vinyl acetate copolymer having acid and acrylate functional groups can be from about 0.865 to about 1.5 g / cm 3 About 0.940g / cm 3 In other embodiments, the density of the polyolefin blended with the ethylene vinyl acetate copolymer having acid and acrylate functional groups may be about 0.865 g / cm 3 To about 0.940g / cm 3 , about 0.865g / cm 3 To about 0.920g / cm 3 , about 0.865g / cm 3 To about 0.900g / cm 3 , about 0.865g / cm 3 To about 0.880g / cm 3 , about 0.880g / cm 3 To about 0.940g / cm 3 , about 0.880g / cm 3 To about 0.920g / cm 3 , about 0.880g / cm 3 To about 0.900g / cm 3 , about 0.900g / cm 3 To about 0.940g / cm 3 , about 0.900g / cm 3 To about 0.920g / cm 3 or about 0.920g / cm 3 To about 0.940g / cm 3 .

[0044] In further embodiments, the polyolefin blended with the ethylene vinyl acetate copolymer having acid and acrylate functional groups may include low density polyethylene (LDPE); linear low density polyethylene (LLDPE); ultra low density polyethylene (ULDPE); very low density polyethylene (VLDPE); single site catalyzed linear low density polyethylene, which includes both linear low density resins and substantially linear low density resins (m-LLDPE); medium density polyethylene (MDPE); and high density polyethylene (HDPE). In particular embodiments, the one or more printed layers may include LLDPE. The density of LLDPE may be approximately 0.915 grams per cubic centimeter (g / cm 3) to about 0.955g / cm 3 、0.915g / cm 3 To about 0.945g / cm 3 、0.915g / cm 3 To about 0.935g / cm 3 、0.915g / cm 3 To about 0.925g / cm 3 The LLDPE may have a melt index of about 0.70 g / 10 min to about 1.0 g / 10 min, about 0.80 g / 10 min to about 1.0 g / 10 min, or about 0.90 to about 1.0 g / 10 min. Various commercial embodiments of ethylene-based polymers are considered suitable for blending with ethylene vinyl acetate copolymers having acid and acrylate functional groups for use in the one or more printed layers. For example, suitable ethylene-based polymers are available from The Dow Chemical Company under the trademark DOWLEX TM GM 8070 was purchased commercially.

[0045] Embodiments of the printing system may optionally comprise one or more additional layers.In embodiments, the one or more additional layers may comprise a sealing layer, a barrier layer, a tie layer, or a combination thereof.

[0046] In some embodiments, the printing system may optionally include one or more sealing layers. Without being bound by theory, the one or more sealing layers may allow the multilayer film structure to be heat-sealable, contain the product, and protect one or more optional barrier layers. Various commercial embodiments are believed to be suitable for the one or more sealing layers. For example, a suitable sealing layer may be used as an AFFINITY TM PL 1888G;ELITE TM 5401G;DOWLEX TM 2045; LDPE 611A was commercially available from The Dow Chemical Company.

[0047] In some embodiments, the printing system may optionally include one or more barrier layers. In embodiments, the one or more core layers may be located between the one or more printing layers and the one or more barrier layers. Without being bound by theory, the one or more barrier layers may help provide chemical resistance and prevent the transmission of moisture, light, and oxygen. In embodiments, the one or more barrier layers may include one or more of polyamide, ethylene vinyl alcohol, or polyvinylidene chloride (PVDC). Various commercial embodiments are believed to be suitable for the one or more barrier layers. For example, suitable sealing layers are available as ULTRAMID C33 from BASF, as EVAL from Kuraray, as SARAN from SK Chemicals, and as ELITE TM 5960G and XUS 59900.94 were commercially available from The Dow Chemical Company.

[0048] In some embodiments, the printing system may optionally include one or more tie layers that can adhere the polyolefin-based film to one or more barrier layers. For example, a suitable tie layer may be a BYNEL TM 41E710 and AMPLIFY TM TY 1451B was purchased commercially.

[0049] Reference will now be made in detail to embodiments of methods of printing utilizing the printing system described herein.

[0050] As previously described, embodiments of the printing methods described herein can include transferring an ink composition onto a printed layer of a multilayer film. The ink composition can include charged ink particles dispersed in a hydrocarbon liquid; and the multilayer film can include a polymer core layer and one or more printed layers adjacent to the polymer core layer, the one or more printed layers having at least 50 wt.% of an ethylene vinyl acetate copolymer having acid and acrylate functional groups.

[0051] In an embodiment, the printing method can utilize a digital printing press. Various commercial embodiments of digital printing presses are considered suitable. For example, a suitable digital printing press is available under the trademark Indigo TM Commercially available from HP.

[0052] During a digital printing process, a laser array can be used to synthesize an image to be printed (i.e., a print image) onto a photosensitive, photo-imaging plate. In embodiments, the print image can be synthesized onto the photo-imaging plate as an electrostatic field. Charged particles of the ink composition can be attracted by the electrostatic field formed on the photo-imaging plate, thereby allowing the charged particles of the ink composition to be deposited on the photo-imaging plate. In conventional printing methods using fixed etching plates, the ink is attracted to the substrate by physically transferring the ink from an ink tray to a roller. In embodiments of the printing method described herein, the ink composition is attracted to the photo-imaging plate by an electrical charge, rather than by physical transfer from an ink tray to a roller.

[0053] In case ink composition is placed on the photo imaging plate, by direct contact between the heated rubber cloth and the ink composition on the photo imaging plate, then the ink composition placed is directly transferred on the heated rubber cloth. The heated rubber cloth may also be referred to as a "hot rubber cloth". On the heated rubber cloth, the ink particles of the ink composition may be melted into a smooth ink film. The heated rubber cloth may then be transferred to the ink film on the multilayer film. The heated rubber cloth may serve as a shock absorber and pressure pad to ensure that the ink film is transferred evenly on the multilayer film. In another embodiment, the heated rubber cloth may be transferred to the ink film on the one or more print layers of the multilayer film.

[0054] In embodiments, the heated blanket may be heated to a temperature of about 100° C. to about 200° C. In some embodiments, the heated blanket may be heated to a temperature of about 100° C. to about 180° C., about 100° C. to about 160° C., about 100° C. to about 140° C., about 100° C. to about 120° C., about 120° C. to about 200° C., about 120° C. to about 180° C., about 120° C. to about 160° C., about 120° C. to about 140° C., about 140° C. to about 200° C., about 140° C. to about 180° C., about 140° C. to about 160° C., about 160° C. to about 200° C., about 160° C. to about 180° C., or about 180° C. to about 200° C.

[0055] The printing method may include one or more additional steps. In some embodiments, the printing method may not include pre-transfer heating. In other embodiments, the printing method may include pre-transfer heating. In some embodiments, the ink composition may be supplied in a concentrated form, which may need to be diluted so that the ink composition can be printed. When the ink composition is supplied in a concentrated form, the printing method may include supplying the concentrated ink composition to an ink supply tank, diluting the concentrated ink composition, and combining the diluted ink composition with a carrier fluid to form an ink composition comprising charged ink particles dispersed in a liquid.

[0056] Test Method

[0057] The test methods include the following:

[0058] Melt index (I2)

[0059] To test melt index (I2), ethylene-based polymer samples are measured according to ASTM D1238 at 190°C and 2.16 kg. Values ​​are reported in grams per 10 minutes, which corresponds to the number of grams eluted per 10 minutes. Propylene-based polymers are measured according to ASTM D1238 at 230°C and 2.16 kg.

[0060] density

[0061] To test density, samples were prepared and measured according to ASTM D4703 and expressed in grams per cubic centimeter (g / cc or g / cm 3 ) Reported. Measurements were made using ASTM D792, Method B, within one hour of sample compression.

[0062] ASTM D1525 (Vicat softening point)

[0063] The Vicat softening point is used to determine the temperature at which a specimen undergoes a specified needle penetration when subjected to specified controlled test conditions according to ASTM D1525 at a heating rate of 120°C per hour and a load of 10N.

[0064] ASTM2252-03 (ink anchoring)

[0065] ASTM 2252-03 is a standard test for evaluating the adhesion of inks or coatings to flexible packaging materials using adhesive tape. ASTM 2252-03 can be used for flexible packaging materials whose surfaces will not be damaged by the application and removal of adhesive tape. To perform ASTM 2252-03, 3M #610, Sellotape office tape, or other adhesive tapes known in the art can be used. For ASTM 2252-03, the width of the adhesive tape is approximately 19 mm to 25 mm (approximately 3 / 4 inch to 1 inch).

[0066] To perform ASTM 2252-03, first place the sample to be tested on a flat surface. The sample should be flat and smooth without wrinkles, creases, or folds. Then, cut a strip of tape long enough to cover the printed (or coated) area of ​​interest on the sample. When testing large areas, several shorter strips of tape may also be used. Apply the tape to the sample using smooth, even motions without wrinkling the tape or sample. Then, rub the surface of the tape (i.e., with your thumb or index finger) to ensure that the tape is completely adhered to the sample and there are no bubbles on the surface. Then, lay the sample flat on the surface (i.e., with one hand) while peeling the tape off at an angle of approximately 120 to 150° (i.e., with your other hand). The setup time (the time the tape remains on the sample) of the Scotch tape should be consistent for each sample to be tested. Typically, the tape is lifted and pulled back in an even, moderate motion at a rate of approximately 305 mm to 460 mm (12 inches to 18 inches) per second.

[0067] Once the tape is pulled from the sample, the sample is inspected for missing print or coating gaps. The tape is also inspected for any ink or coating removed from the test sample. As an aid to visual inspection of a reference standard, a control can be created and used to determine the degree of transfer. The results are then recorded, characterizing the degree of adhesion using a mutually agreed-upon reference. If multiple ink colors are present, the results may vary by color depending on the ink formulation and may be reported accordingly.

[0068] ASTMF904 (adhesion)

[0069] ASTM F904 is used to test for bond strength and temperature resistance. To perform ASTM F904, ply separation is initiated mechanically by applying heat or using a solvent. The test specimen's separation line is then placed in the grips of an Instron tensile tester (Model #4442). Next, the grips are separated, and the force required to further separate the plies is measured and defined as the bond strength.

[0070] Examples

[0071] The following examples illustrate features of the present disclosure but are not intended to limit the scope of the present disclosure.The following experiments analyze the performance of an embodiment of the printing system described herein.

[0072] Example 1 - Production of Control Sample, Sample 1 and Comparative Sample AI

[0073] Control sample (film with primer)

[0074] The control sample used was a multilayer film containing a primer. The control sample was a 2-layer blown film prepared having the general formula A layer / B layer containing 80 wt.% of layer A and 20 wt.% of layer B, based on the total weight of the multilayer film. Layer A contained 80 wt.% of ELITE TM 5410 (available from The Dow Chemical Company, Midland, Michigan) and 20 wt.% of LDPE 219M (available from The Dow Chemical Company, Midland, Michigan). The B layer contained 100 wt.% of DOWLEX TM GM 8070 (available from The Dow Chemical Company, Midland, Mich.) Then, 0.1-0.4 grams per square meter (gsm) of primer (DigiPrime, available from Michelman, Inc.) was applied to the B layer prior to printing.

[0075] Control samples were produced using a casting extruder and the following process conditions:

[0076] Table 1. Process conditions used to produce control films.

[0077] blower 90％ Output (take off) 8.2 m / min Total output 10 kg / hour mold temperature 260℃ Temperature distribution 190℃ / 220℃ / 235℃ / 250℃ / 250℃ / 260℃

[0078] Sample 1 (multilayer film with printed layer)

[0079] Sample 1 is a 2-layer film prepared having the general formula A layer / B layer comprising 80 wt.% of A layer and 20 wt.% of B layer, based on the total weight of the multilayer film.

[0080] Layer A, the core layer of the multilayer film, contains 80 wt.% of ELITE TMThe B layer of Sample 1 is an ethylene vinyl acetate copolymer having acid and acrylate functionality, which contains approximately 18% vinyl acetate, 2% isobutyl acrylate, and 2% methacrylic acid. The ethylene vinyl acetate copolymer having acid and acrylate functionality was prepared by melt blending 80 wt.% of an ethylene vinyl acetate polymer with 20 wt.% of a terpolymer of ethylene isobutyl acrylate and methacrylic acid at 200° C. using a single screw extruder. The ethylene vinyl acetate polymer has 23 wt.% vinyl acetate and a melt index of 2 g / 10 min as measured at 190° C. and 2.16 kg. The ethylene isobutyl acrylate methacrylic acid terpolymer had a melt index of 10 g / 10 minutes and had 10 wt. % isobutyl acrylate and 10 wt. % methacrylic acid.

[0081] Film of Sample 1 was produced using a cast extruder and the following process conditions:

[0082] Table 2. Process conditions used to produce the film of Sample 1.

[0083] blower 90％ Output 8.2 m / min Total output 10 kg / hour mold temperature 260℃ Temperature distribution 190℃ / 220℃ / 235℃ / 250℃ / 250℃ / 260℃

[0084] Comparative Sample AI (Multilayer Film with Comparative Printing Layer)

[0085] Comparative Sample AI was prepared having a general formula A / B containing 80 wt.% of Layer A and 20 wt.% of Layer B, based on the total weight of the multilayer film. Layer A, i.e., the core layer of each multilayer film, contained 80 wt.% of ELITE TM 5410 (available from The Dow Chemical Company, Midland, Mich.) and 20 wt.% LDPE 219M (available from The Dow Chemical Company, Midland, Mich.) The B layer of each film contained 100 wt.% functionalized with a polar resin according to the composition provided in Table 3.

[0086] Table 3. Print layer compositions used for digital printing trials.

[0087]

[0088] Films were produced using a cast extruder and the following process conditions:

[0089] Table 4. Process conditions used to produce films of Comparative Samples AI.

[0090]

[0091]

[0092] Example 2 - Performance Analysis of Control Sample, Sample 1, and Comparative Sample AI

[0093] For Example 2, ink was digitally printed onto the printed layers of the control sample, Sample 1, and Comparative Samples AI. To perform the digital printing, a laser was used to charge the plate cylinder, with a voltage difference producing the spectrum of the desired image. The ink was then applied to the charged cylinder and deposited where the voltage difference was detected. The ink was dried to remove the carrier. The ink was then transferred to a heated blanket set at 105°C and discharged from the plate cylinder. The blanket was used to thermally transfer the image by applying pressure to a tensioned flexible substrate. The ink composition printed on the control sample, Sample 1, and Comparative Samples AI is commercially available as electronic ink from Hewlett-Packard Company.

[0094] Once digital printing was completed on the Control Sample, Sample 1, and Comparative Sample AI, the films were tested for ink anchoring using 3M tape according to ASTM 2252-03 as described herein. The results of the ink anchoring test ASTM 2252-03 are summarized in Table 5.

[0095] The adhesive strength of the control sample, sample 1, and comparative samples AF was also tested before and after heat sealing. To test the adhesive strength of the control sample, sample 1, and comparative samples AF, each of the printed films was bonded to a solvent-based adhesive, ADCOTE TM 577 (available from The Dow Chemical Company, Midland, Michigan) was laminated to a biaxially oriented polypropylene film. After curing, the bond strength was measured before and after heat sealing according to ASTM F904 as described herein. The bond strength results for the control sample, Sample 1, and Comparative Samples AF are summarized in Table 5.

[0096] Table 5. Results of ink adhesion testing and adhesive strength for the control sample, Sample 1, and Comparative Samples AF.

[0097]

[0098] As shown in the results of Table 5, the control sample, sample 1, and comparative sample A passed the ink anchoring test, ASTM 2252-03, while comparative samples BF and GI failed. Through the ink anchoring test, the control sample and comparative sample A showed that their printed layers were able to adequately retain the ink composition.

[0099] The above results in Table 5 further indicate that Sample 1 delivers higher adhesion than the Control Sample, Comparative Sample A, and Comparative Sample F when delamination is promoted.

[0100] Example 3 - Effect of Corona Treatment on Sample 1 and Comparative Sample A

[0101] For Example 3, Sample 1 and Comparative Sample A were corona treated online at 1-2 kW immediately after the production of the films of Sample 1 and Comparative Sample A. The films were then treated a second time at 1 kW immediately before printing to observe the effect of corona treatment on ink adhesion. Ink was digitally printed onto the printed layers of Sample 1 and Comparative Sample A as described in Example 2.

[0102] Once digital printing was completed on the print layer of Sample 1 and Comparative Sample A, the films were tested for ink anchoring according to ASTM 2252-03 as described in Example 3. The ink anchoring test results for corona treated and untreated Sample 1 and Comparative Sample A are summarized in Table 6.

[0103] Table 6. Ink adhesion test results for Sample 1 and Comparative Sample A with and without corona treatment.

[0104] sample Tape test Sample 1, corona treated pass Sample 1, untreated pass Comparative sample A, corona treated Failed Comparative sample A, untreated pass

[0105] As shown in the results of Table 6, when Comparative Sample A was corona treated, ink anchoring of the film was severely affected, resulting in a failure in the tape test. However, both corona-treated and untreated Sample 1 passed the tape test. Therefore, these results show that, unlike Comparative Sample A, the printed layer of Sample 1 adequately retained the ink composition when corona-treated or untreated, and was not significantly affected by the corona treatment.

[0106] Example 4 - Production of printed layers comprising blends

[0107] Samples 2-5 and Comparative Sample JN (Multilayer Film with Printed Layer)

[0108] In Example 4, printed layers were tested by producing 7 layers of film comprising a blend of an ethylene-based polymer and a polar resin. Each film had a thickness of approximately 100 microns and a width of approximately 12 inches (approximately 30.48 centimeters).

[0109] For each film of Samples 2-5 and Comparative Samples JN, the layers extruded by Extruder GC were identical. Extruders C, D, and E contained HDPE (commercially available from The Dow Chemical Company as XUS 59900.94) and LDPE (commercially available from The Dow Chemical Company as AGILITY TM 1021 is commercially available from The Dow Chemical Company). Extruders F and G contain DOWLEX TM 8070G (available from The Dow Chemical Company). The film layers of Samples 2-8 and Comparative Samples JN are subsequently provided in Tables 7 and 8.

[0110] Table 7. Layers of Samples 2-5 and Comparative Examples JN.

[0111]

[0112] Samples 2-5 and Comparative Samples JN differ in their printed layers, extruded through Extruders A and B. Samples 2-5 comprise ethylene vinyl acetate copolymers having acid and acrylate functional groups blended with varying amounts of ethylene-based polymers including LLDPE (available as DOWLEX TM 8070G is commercially available from The Dow Chemical Company), low melt index copolymers (available as VERSIFY TM 2000 commercially available from The Dow Chemical Company) or HDPE (available as VERSIFY TM 2000 from The Dow Chemical Company). The ethylene vinyl acetate copolymer having acid and acrylate functional groups comprises approximately 18% vinyl acetate, 2% isobutyl acrylate, and 2% methacrylic acid, based on the total weight of the ethylene vinyl acetate copolymer having acid and acrylate functional groups. The printed layer of Comparative Sample M comprises an ethylene vinyl acetate copolymer (available as ELVAX TM 3128 is commercially available from The Dow Chemical Company.) The printed layer of Comparative Sample N comprises LLDPE (available as DOWLEX TM 8070G is commercially available from The Dow Chemical Company. The compositions of the printed layers for each of Samples 2-5 and Comparative Samples JN are subsequently provided in Table 8.

[0113] Table 8. Composition of the printed layers of Samples 2-5 and Comparative Examples JN.

[0114]

[0115] Example 5 - Performance Analysis of Printed Layers Including Blends

[0116] For Example 5, an image was digitally printed onto the printed layer of the control sample, as well as samples 2-5 and comparative sample JN. To perform digital printing, a laser was used to charge the plate cylinder; the voltage difference produced the spectrum of the desired image. Ink was then applied to the charged cylinder and deposited where the voltage difference was detected. The ink dried to remove the carrier. The ink was then transferred to a heated blanket set at 105°C and discharged from the plate cylinder. The blanket was used to thermally transfer the image by applying pressure to a tensioned flexible substrate. This process was repeated in a half-rotation loop to digitally print onto the printed layer of the control sample, as well as samples 2-5 and comparative sample JN.

[0117] Once the ink compositions were digitally printed onto the printed layers of the control sample, as well as samples 2-5 and comparative sample JN, an ink anchoring test was performed using 3M tape according to ASTM 2252-03. The ink anchoring test consisted of testing each fresh sample immediately after digital printing, testing each sample 10 minutes after digital printing, and testing each sample 60 minutes after digital printing. The results of the ink anchoring test are summarized in Table 9.

[0118] The control sample and the printed layers of samples 2-5 and comparative sample JN were also tested for adhesive strength according to ASTM F904 as described herein. The adhesive strength results for the control sample and the printed layers of samples 2-5 and comparative sample JN are also summarized in Table 9.

[0119] Table 9. Results of ink adhesion test and adhesive strength test.

[0120]

[0121]

[0122] As shown in the results of Table 9, Samples 2 and 3 passed the ink anchoring test ASTM 2252-03, while Samples 4, 5, and Comparative Sample JN failed. As provided in Table 9, Samples 2 and 3 both contained a printed layer comprising greater than 50 wt.% of an ethylene vinyl acetate copolymer having acid and acrylate functional groups and approximately 18% VA, 2% iBA, and 2% MAA. From these results, it is apparent that for the control samples, when the package design requires an inside / outside (lap seal) seal, the use of a primer may present several disadvantages, including increased process complexity, additional costs associated with the process, and poor sealing.

[0123] Obviously, modifications and variations are possible without departing from the scope of the disclosure as defined in the appended claims. More specifically, although some aspects of the disclosure are identified herein as preferred or particularly advantageous, it is contemplated that the disclosure is not necessarily limited to these aspects.

Claims

1. A printed article comprising: an ink composition comprising charged ink particles dispersed in a liquid; as well as A multilayer film comprising: polymer core layer; as well as one or more printed layers adjacent to the polymeric core layer, wherein the one or more printed layers comprise at least 50 wt.% of an ethylene vinyl acetate copolymer having acid and acrylate functional groups; If present, the polyolefin blended with the ethylene vinyl acetate copolymer is selected from low density polyethylene LDPE, linear low density polyethylene LLDPE, ultra low density polyethylene ULDPE, very low density polyethylene VLDPE, or combinations thereof; The ethylene vinyl acetate copolymer comprises, based on the total weight of the ethylene vinyl acetate copolymer, 0.5 wt.% to 4 wt.% of methacrylic acid or acrylic acid, 0.5 wt.% to 4 wt.% of acrylic acid ester, 7 wt.% to 40 wt.% of vinyl acetate, and the balance ethylene; The ink composition is deposited on the printed layer; and The printed article passed the ink anchoring test conducted according to ASTM 2252-03.

2. The printed article of claim 1 , wherein the ethylene vinyl acetate copolymer has a density of 0.890 g / cm 2 when measured according to ASTM D792. 3 to 0.980g / cm 3 .

3. The printed article of claim 1, wherein the ethylene vinyl acetate copolymer has a melt flow rate of 0.5 to 20.0 g / 10 minutes when measured according to ASTM D1238 at 190°C and 2.16 kg.

4. The printed article of claim 2, wherein the ethylene vinyl acetate copolymer has a melt flow rate of 0.5 to 20.0 g / 10 min when measured according to ASTM D1238 at 190°C and 2.16 kg.

5. The printed article of any one of claims 1 to 4, wherein the ethylene vinyl acetate copolymer has a melt flow rate of 1.0 to 10.0 g / 10 min when measured according to ASTM D1238 at 190°C and 2.16 kg.

6. The printed article of any one of claims 1 to 4, wherein the one or more printed layers further comprise a linear low-density ethylene-based polymer.

7. The printed article of any one of claims 1 to 4, wherein the polymeric core layer comprises an ethylene-based polymer having a 2% secant modulus greater than 150 MPa.

8. The printed article of any one of claims 1 to 4, further comprising one or more of a sealing layer, a barrier layer, a tie layer, or a combination thereof.

9. The printed article according to any one of claims 1 to 4, wherein the linear low density polyethylene (LLDPE) is a single site catalyzed linear low density polyethylene.

10. A printing method, comprising: The ink composition is transferred to a printed layer of the multilayer film to produce a printed product, wherein: The ink composition includes charged ink particles dispersed in a liquid; The multilayer film includes a polymer core layer and one or more printed layers adjacent to the polymer core layer; The one or more printed layers include at least 50 wt.% of an ethylene vinyl acetate copolymer having acid and acrylate functional groups; The ethylene vinyl acetate copolymer comprises, based on the total weight of the ethylene vinyl acetate copolymer, 0.5 wt.% to 4 wt.% of methacrylic acid or acrylic acid, 0.5 wt.% to 4 wt.% of acrylic acid ester, 7 wt.% to 40 wt.% of vinyl acetate, and the balance ethylene; If present, the polyolefin blended with the ethylene vinyl acetate copolymer is selected from a low density polyethylene LDPE, a linear low density polyethylene LLDPE, an ultra low density polyethylene ULDPE, a very low density polyethylene VLDPE, or a combination thereof; and The printed product passed the ink anchoring test according to ASTM 2252-03.

11. The printing method of claim 10, wherein the ethylene vinyl acetate copolymer has a density of 0.890 g / cm2 when measured according to ASTM D792. 3 to 0.980g / cm 3 . 12 . The printing method of claim 10 , wherein the ethylene vinyl acetate copolymer has a melt flow rate of 0.5 to 20.0 g / 10 min when measured at 190° C. and 2.16 kg according to ASTM D1238. 13 . The printing method of claim 11 , wherein the ethylene vinyl acetate copolymer has a melt flow rate of 0.5 to 20.0 g / 10 min when measured at 190° C. and 2.16 kg according to ASTM D1238.

14. The printing method according to any one of claims 10 to 13, wherein the ink composition is directly transferred onto the printed layer of the multilayer film without a primer.

15. A printing method according to any one of claims 10 to 13, wherein the polymer core layer of the multilayer film comprises an ethylene-based polymer having a 2% secant modulus greater than 250 MPa.

16. The printing method according to any one of claims 10 to 13, wherein the linear low density polyethylene (LLDPE) is a single-site catalyzed linear low density polyethylene.

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