Coated printing substrates and their preparation process

Abstract

A process for producing a coated printing substrate, the process comprising: (a) providing a printing substrate, the substrate including a surface on which a layer of ink is present in one or more regions; (b) combining Components A and B to form a urethane coating composition, wherein Component A comprises a polyisocyanate prepolymer A1, the polyisocyanate prepolymer A1 being the reaction product of a polyisocyanate monomer A1a and an isocyanate poly-reactive compound A1b, and Component B comprises one or more polyols B1, the urethane coating composition having an isocyanate index greater than 0.9; and (c) applying a layer of the urethane coating composition to the surface. Also provided is a coated printing substrate made by such a method.

Description

[Technical Field]

[0001] In many cases, it is desirable to use printing inks to create images on plastic surfaces. Afterward, it is usually desirable to protect the printed surface. Without protection, the image is susceptible to damage from scratches that may occur, for example, during transport or handling, and / or distortion when the printed surface is heated, for example, during sealing operations. Historically, it was common to protect printed images by laminating a transparent plastic film onto the printed surface. Such laminates often have one or more undesirable characteristics, such as increasing the complexity or cost of the manufacturing process.

[0002] International Publication No. 2016 / 196168 describes a coated film in which the film contains polyethylene and the coating contains polyurethane.

[0003] It is desirable to provide a method for creating a coated printing substrate that has one or more of the following advantages: good appearance, good abrasion resistance, good high temperature resistance, and / or good chemical resistance. Preferably, the coated printing substrate has one or more of these advantages to a sufficient extent that a coating plastic layer does not need to be attached to the coated surface.

[0004] The following is a description of the present invention.

[0005] A first aspect of the present invention is a process for manufacturing a coated printing substrate, (a) To provide a printing substrate, wherein the substrate includes a surface present in one or more regions of the ink layer, (i) one or more olefin copolymers, (ii) One or more appearance additives selected from one or more pigments, one or more dyes, and mixtures thereof, (iii) To provide a product comprising one or more conductive additives, (b) Combining components A and B to form a urethane coating composition, Component A contains polyisocyanate prepolymer A1, and polyisocyanate prepolymer A1 is a reaction product of polyisocyanate monomer A1a and isocyanate polyreactive compound A1b. Component B contains one or more polyol B1, The urethane coating composition has an isocyanate index greater than 0.9, and (c) A process comprising applying a layer of urethane coating composition to a surface.

[0006] A second aspect of the present invention is a coated printing substrate produced by the method of the first aspect of the present invention.

[0007] The following is a detailed description of the present invention.

[0008] As used herein, the following terms have the definitions set forth unless the context otherwise clearly indicates.

[0009] As used herein, "polymer" and "plastic" are synonymous. A polymer is a molecule made up of many repeating units. Two or more types of repeating units may exist; that is, a polymer can be a homopolymer (exactly one type of repeating unit) or a copolymer (two or more types of repeating units). A polymer has a molecular weight of 5,000 or more. A polymer can be linear, branched, crosslinked, or a combination thereof.

[0010] Polyolefins are polymers in which 75% or more of the polymer weight consists of repeating units having the following structure I: [ka] In the formula, R 1 , R 2 , R 3 , and R 4is independently hydrogen or an olefin group. R 1 , R 2 , R 3 , and R 4 any one of which may be the same as or different from any one of the other Rs 1 , R 2 , R 3 , and R 4 Two or more of R 1 , R 2 , R 3 , and R 4 may be joined together to form a cyclic structure.

[0011] Polyethylene is a polymer having 75% by weight or more of repeating units based on the weight of the polymer with the following structure II. [Chemical formula]

[0012] As used herein, an olefin copolymer is a polymer having repeating units of structure I and also having repeating units containing one or more oxygen atoms. Suitable oxygen-containing repeating units include, for example, acrylic units (structure III), ester units (structure IV), and carbonyl units (structure V). [Chemical formula] R 5 is methyl or hydrogen, and R 6 is hydrogen or a substituted or unsubstituted alkyl group. R 8 and R 9Each is independently a substituted or unsubstituted alkyl group. Suitable substituents include a hydroxyl group, a carboxyl group, a nitrogen-containing group, a carbon-carbon double bond-containing group, other substituents, and combinations thereof. In the olefin copolymer, the repeating units of Structure I and one or more oxygen-containing repeating units can be arranged in the copolymer in any order, including, for example, random, alternating, block, branched, or any combination thereof. In the olefin copolymer, at least 75% by weight of the repeating units, based on the weight of the polymer, are either of Structure I or an oxygen-containing repeating unit.

[0013] As used herein, an isocyanate-reactive group is a chemical group that can react with an isocyanate group to form a covalent bond between the isocyanate group and the isocyanate-reactive group. An intact isocyanate group is an isocyanate group that has not reacted with an isocyanate-reactive group. An intact isocyanate-reactive group is an isocyanate-reactive group that has not reacted with an isocyanate group.

[0014] A compound having one or more isocyanate-reactive groups is characterized by its functionality, which is the number of isocyanate-reactive groups per molecule. In a mixture of compounds each having one or more isocyanate-reactive groups per molecule, the functionality of the mixture is the number-average functionality. Similarly, a compound having one or more isocyanate groups is characterized by its functionality, which is the number of isocyanate groups per molecule. In a mixture of compounds each having one or more isocyanate groups per molecule, the functionality of the mixture is the number-average functionality.

[0015] A compound having an isocyanate-reactive group and a functionality of 2 or more is known herein as an "isocyanate polyreactive" compound.

[0016] A polyol is a compound having two or more hydroxyl groups. A polyol having two or more ether bonds is a polyether polyol. A polyol having two or more ester bonds is a polyester polyol. A polyol having two or more urethane bonds is a polyurethane polyol. A polyol having two or more carbonate bonds is a polycarbonate polyol. A polyol having two or more residues of the ring-opening polymerization reaction of epsilon-caprolactone is a polycaprolactone polyol. A polyol can be characterized by an "OH value" determined by test ASTM D4274-16 (American Society of Testing and Materials, Conshohocken, PA, USA). A low molecular weight polyol has a molecular weight of 300 or less.

[0017] A composition containing intact isocyanate groups can be characterized by an "isocyanate index", which is the ratio of the number of all intact isocyanate groups in the composition to the number of all intact isocyanate-reactive groups in the composition. A composition containing intact isocyanate groups can also be characterized by an "NCO content", which is the weight percentage of isocyanate groups based on the weight of the composition, determined by test ASTM D2572-19 (American Society of Testing and Materials, Conshohocken, PA, USA). When the composition contains a solvent, the NCO content can be reported as "with solvent", which means that the NCO content rate is based on the weight of the entire composition, or the NCO content can be reported as "without solvent", which means that the NCO content rate is based on the weight of the non-solvent part of the composition.

[0018] A compound containing one or more isocyanate groups per molecule is an isocyanate. A compound containing two or more isocyanate groups per molecule is a polyisocyanate. An isocyanate having one or more aromatic rings is an aromatic isocyanate. An isocyanate that does not have aromatic rings in its molecule is an aliphatic isocyanate. A polyisocyanate monomer is a polyisocyanate having a molecular weight of 700 or less.

[0019] As used herein, the solvent is a compound that is liquid over a temperature range including 10°C to 30°C and does not participate in the chemical reaction between the isocyanate group and the isocyanate-reactive group. The solvent has a boiling point of 200°C or less.

[0020] As used herein, a fatty compound is a compound comprising a linear hydrocarbon group having eight or more carbon atoms bonded to each other in a line. A fatty compound comprising a carboxyl group or a carboxylate anion is a fatty acid. A fatty compound comprising a hydroxyl group is a fatty alcohol.

[0021] As used herein, a fatty triglyceride is a compound having a structure of a triester of glycerol with three fatty acids. The portion of the fatty triglyceride that would have originated from one of those fatty acids (when the fatty triglyceride is formed by an esterification reaction between a fatty acid and glycerol) is known as a fatty acid residue. As used herein, a natural oil polyol is a fatty triglyceride having two or more hydroxyl groups.

[0022] As used herein, a wax ester is a compound having an ester structure of a fatty acid and a fatty alcohol and being solid over a temperature range including 10°C to 40°C. Mixtures of wax esters are also referred to herein as wax esters. The term “wax ester” also includes mixtures in which 80% by weight or more of the components are one or more wax esters and the remaining 20% ​​by weight or less are substances that are not wax esters.

[0023] As used herein, a printing surface is a surface present in one or more areas of the printing ink. On the printing surface, the printing ink is dry, meaning that the printing ink contains all compounds having a boiling point of 120°C or less in an amount of 10% or less by weight of the printing ink. The printing ink contains 15% by weight or more of one or more olefin copolymers based on the weight of the printing ink. The printing ink also contains one or more pigments, one or more dyes, or mixtures thereof. Digital printing ink also contains one or more conductive additives. Conductive additives are also known as charge directors or imaging agents. Conductive additives increase the conductivity of the ink.

[0024] As used herein, surface wetting refers to the tendency of a liquid to form a thin, elongated layer rather than rounded localized beads when placed on a surface. Herein, the greater the tendency of such a liquid to form a thin, elongated layer rather than rounded localized beads, the better the wetting is considered to be. Specifically, herein, the class of liquids used to evaluate wetting is a class of liquids comprising 50% by weight or more of one or more hydrocarbon compounds and also comprising (i) one or more ethylene copolymers, (ii) one or more appearance additives selected from one or more pigments, one or more dyes, and mixtures thereof, and (iii) one or more imaging agents.

[0025] As used herein, TDI is toluene diisocyanate and MDI is diphenylmethane diisocyanate.

[0026] The present invention includes a coating composition formed by combining component A and component B.

[0027] Component A comprises one or more polyisocyanates. Component A preferably comprises one or more prepolymers A1, which are reaction products of one or more polyisocyanate monomers A1a and one or more isocyanate polyreactive compounds A1b. Prepolymer A1 is a polyisocyanate. Polyisocyanate monomer A1a preferably comprises one or more aromatic polyisocyanate monomers, or one or more aliphatic polyisocyanate monomers, or a blend thereof. More preferably, polyisocyanate monomer A1a comprises one or more aromatic polyisocyanate monomers. More preferably, polyisocyanate monomer A1a comprises one or more monomers selected from 2,6-TDI, 2,4-TDI, 2,4'-MDI, 4,4'-MDI, and mixtures thereof.

[0028] The isocyanate polyreactive compound A1b preferably comprises one or more polyols. Suitable polyols for the isocyanate polyreactive compound A1b include, for example, polyether polyols, polyester polyols, polyether polyester polyols, polyurethane polyols, polycarbonate polyols, polycaprolactone polyols, natural oil polyols, and blends thereof. Preferred polyols for the isocyanate polyreactive compound A1b are polyether polyols, polyester polyols, and blends thereof. Polyether polyols, low molecular weight polyols, and blends thereof are more preferred. Suitable low molecular weight polyols include, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, trimethylolpropane, triisopropanolamine, and blends thereof.

[0029] Preferably, isocyanate polyreactive compound A1b comprises one or more isocyanate polyreactive compounds having a functional value of 2 or more. Preferably, isocyanate polyreactive compound A1b comprises one or more isocyanate polyreactive compounds having a functional value of 6 or less, more preferably 5 or less, and more preferably 4 or less.

[0030] When the isocyanate polyreactive compound A1b contains one or more polyols, preferably the polyols have a molecular weight of 50 or more, and more preferably 100 or more. When the isocyanate polyreactive compound A1b contains one or more polyols, preferably the polyols have a molecular weight of 4000 or less, and more preferably 2000 or less.

[0031] Component A may or may not contain a solvent. Examples of suitable solvents are ethyl acetate, propyl acetate, cyclohexane, methyl acetate, methyl ether ketone, toluene, and mixtures thereof. Preferred solvents are ethyl acetate, propyl acetate, cyclohexane, methyl ether ketone, and mixtures thereof, with ethyl acetate, propyl acetate, cyclohexane, and mixtures thereof being more preferred.

[0032] When a solvent is present in component A, preferably all components of component A dissolve in the solvent. Preferably, the amount of solvent in component A is 20% by weight or more, more preferably 30% by weight or more, based on the weight of component A. Preferably, the amount of solvent in component A is 70% by weight or less, more preferably 50% by weight or less, based on the weight of component A.

[0033] Preferably, the NCO content of component A containing the solvent is 5% or more, more preferably 7% or more. Preferably, the NCO content of component A containing the solvent is 15% or less, more preferably 13% or less. Preferably, the NCO content of component A without the solvent is 8% or more, more preferably 12% or more. Preferably, the NCO content of component A without the solvent is 25% or less, more preferably 22% or less.

[0034] Preferably, component A comprises one or more fatty triglycerides. Fatty triglycerides in which one or more fatty acid residues have 12 or more carbon atoms, more preferably 16 or more carbon atoms, are preferred. Fatty triglycerides in which one or more fatty acid residues have one or more carbon-carbon double bonds are preferred.

[0035] Preferably, the amount of fatty triglycerides in component A is 0.1% by weight or more, more preferably 0.2% by weight or more, and more preferably 0.3% by weight or more, based on the weight of component A. Preferably, component A contains one or more fatty triglycerides. Preferably, the amount of fatty triglycerides in component A is 10% by weight or less, more preferably 5% by weight or less, and more preferably 3% by weight or less, based on the weight of component A.

[0036] Preferably, component A comprises one or more wax esters. Suitable wax esters include, but are not limited to, cetyl palmitate, palmityl stearate, stearyl stearate, hydrogenated tallow, carnauba wax, beeswax, and mixtures thereof. Cetyl palmitate, palmityl stearate, stearyl stearate, hydrogenated tallow, and mixtures thereof are preferred. A mixture of cetyl palmitate, palmityl stearate, stearyl stearate, and hydrogenated tallow is more preferred.

[0037] Preferably, the amount of wax ester in component A is 0.1% by weight or more, more preferably 0.2% by weight or more, and more preferably 0.3% by weight or more, based on the weight of component A. Preferably, the amount of wax ester in component A is 10% by weight or less, more preferably 5% by weight or less, and more preferably 3% by weight or less, based on the weight of component A.

[0038] Component B comprises one or more isocyanate polyreactive compounds B1. Preferably, isocyanate polyreactive compounds B1 comprise one or more polyols. Suitable polyols for inclusion in isocyanate polyreactive compounds B1 include, for example, polyether polyols, polyester polyols, polyether polyester polyols, polyurethane polyols, polycarbonate polyols, polycaprolactone polyols, natural oil polyols, and blends thereof.

[0039] Preferably, the isocyanate polyreactive compound B1 comprises one or more polyurethane polyols. The polyurethane polyols suitable for use in the isocyanate polyreactive compound B1 are preferably reaction products of one or more polyisocyanate monomers B1a and one or more polyols B1b. The polyisocyanate monomer B1a may be an aromatic polyisocyanate, an aliphatic polyisocyanate, or a blend thereof. Preferably, the polyisocyanate monomer B1a comprises one or more aromatic polyisocyanate monomers. Preferred polyisocyanate monomers in B1a are 2,6-TDI, 2,4-TDI, 2,2'-MDI, 2,4'-MDI, 4,4'-MDI, and mixtures thereof. Preferably, the polyisocyanate monomer B1a comprises one or more polyisocyanate monomers having a functional value of 2 or more.

[0040] Suitable polyols for inclusion in polyol B1b include, for example, polyether polyols, polyester polyols, polyether polyester polyols, polyurethane polyols, polycarbonate polyols, polycaprolactone polyols, natural oil polyols, and blends thereof. Preferred polyols for polyol B1b are polyether polyols, low molecular weight polyols, and blends thereof. Suitable low molecular weight polyols include, for example, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, trimethylene glycol, 1,3-butanediol, 1,4-butanediol, 1,6-hexanediol, trimethylolpropane, triisopropanolamine, and blends thereof.

[0041] Preferably, the amount of polyurethane polyol B1PU in component B is 20% by weight or more, more preferably 30% by weight or more, and more preferably 49% by weight or more, based on the weight of component B. Preferably, the amount of polyurethane polymer B1PU in component B is 95% by weight or less, more preferably 85% by weight or less, and more preferably 75% by weight or less, based on the weight of component B. Preferably, one or more polyols contained in polyol B1b do not react with the isocyanate compound and remain in component B.

[0042] Preferably, component B comprises one or more anti-blocking agents. The anti-blocking agents reduce blocking on the surface of polymer films and other plastic articles, enabling easy processing and handling of the films. The anti-blocking agents may be inorganic or organic. Examples of inorganic anti-blocking agents include, but are not limited to, talc and silica. Examples of organic anti-blocking agents include, but are not limited to, cellulose acetate butyrate. Mixtures of anti-blocking agents are also preferred.

[0043] Preferably, the amount of the blocking inhibitor in component B is 0.05% by weight or more, more preferably 0.1% by weight or more, and more preferably 0.2% by weight or more, based on the weight of component B. Preferably, the amount of the blocking inhibitor in component B is 10% by weight or less, more preferably 5% by weight or less, and more preferably 3% by weight or less, based on the weight of component B.

[0044] Preferably, component B comprises one or a wetting agent. The wetting agent improves the flow and leveling of the liquid and reduces the tendency for the liquid to form pinholes, fish eyes, craters, mottled surfaces (referred to as "orange peel"), or any combination thereof, when the liquid is applied as a layer on a surface. Examples of suitable wetting agents include, but are not limited to, acrylic polymers, siloxanes, and mixtures thereof.

[0045] Preferably, the amount of wetting agent in component B is 0.05% by weight or more, more preferably 0.1% by weight or more, and more preferably 0.2% by weight or more, based on the weight of component B. Preferably, the amount of wetting agent in component B is 10% by weight or less, more preferably 5% by weight or less, and more preferably 3% by weight or less, based on the weight of component B.

[0046] Component B may or may not contain a solvent. Examples of suitable solvents include ethyl acetate, propyl acetate, cyclohexane, methyl acetate, methyl ether ketone, toluene, and mixtures thereof. Preferred solvents are ethyl acetate, propyl acetate, cyclohexane, methyl ether ketone, and mixtures thereof, with ethyl acetate, propyl acetate, cyclohexane, and mixtures thereof being more preferred.

[0047] When a solvent is present in component B, preferably all components of component B dissolve in the solvent. Preferably, the amount of solvent in component B is 5% by weight or more, more preferably 10% by weight or more, based on the weight of component B. Preferably, the amount of solvent in component B is 80% by weight or less, more preferably 70% by weight or less, based on the weight of component B.

[0048] In carrying out the present invention, components A and B are combined, and the resulting mixture is a urethane coating composition. Preferably, components A and B are then completely mixed. A layer of the coating composition is applied to the substrate. It is expected that the isocyanate groups in component A will react with the isocyanate-reactive groups in component B. Preferably, the layer of the coating composition is applied to the substrate when 50 mol% or less of the isocyanate groups in component A have reacted with the isocyanate-reactive groups in component B.

[0049] It is useful to prepare the mixture before any chemical reaction occurs between component A and component B. The isocyanate index of the mixture is 0.9 or higher, preferably 1.0 or higher, more preferably 1.1 or higher, and more preferably 1.2 or higher. The isocyanate index of the mixture is preferably 2 or lower, more preferably 1.8 or lower, and more preferably 1.6 or lower.

[0050] In carrying out the present invention, a layer of the urethane coating composition is applied to the surface of a printing substrate. Preferably, the substrate surface is subjected to a surface treatment after the ink has been applied to the substrate, but before the layer of the urethane coating composition is applied. A suitable surface treatment is one that changes the surface energy of the substrate in a way that improves the wettability of the substrate surface. Examples of suitable surface treatments include, for example, corona treatment and plasma treatment.

[0051] Preferably, the urethane coating composition is liquid at the temperature at which it is applied to the substrate before the curing process. Preferably, when the liquid urethane coating composition is applied to the printed surface of the substrate, it exhibits good wetting in both the areas of the substrate covered by the printing ink and the areas of the substrate (if any) that are in direct contact with the liquid urethane coating composition. That is, the liquid urethane coating composition preferably forms a smooth, unbroken layer over the entire coated portion of the substrate without gaps. Such gaps may be observed when the liquid coating composition retracts from parts of the substrate surface, usually due to surface tension, forming structures such as "beads" or "fish eyes".

[0052] After a layer of the urethane coating composition is applied to a substrate, it is expected that some or all of the isocyanate groups will react with some or all of the isocyanate reactive groups, thus forming a cured polyurethane layer. To accelerate this reaction, the layer of the urethane coating composition may be heated. In this specification, the layer of the urethane coating composition is considered to have become a cured polyurethane layer when 80 mol% or more of the isocyanate groups have reacted. If the urethane coating composition contains one or more solvents, preferably, after the layer of the urethane coating composition is applied to the substrate, the solvents are compelled or permitted to evaporate from the coating composition. When the layer of the urethane coating composition is heated, it is intended that the act of heating the layer of the urethane coating composition on the substrate will help to accelerate the evaporation of the solvents and also accelerate the curing reaction.

[0053] Preferably, the average thickness of the cured polyurethane layer is 0.5 micrometers or more, more preferably 1 micrometer or more. Preferably, the average thickness of the cured polyurethane layer is 10 micrometers or less, more preferably 7.5 micrometers or less, and more preferably 5 micrometers or less.

[0054] The substrate is the printing surface. Preferably, within the area of ​​the substrate covered by the urethane coating composition layer, the portion of the substrate covered by ink is 10% or more, more preferably 20% or more, and more preferably 50% or more. Preferably, within the area of ​​the substrate covered by the urethane coating composition layer, the portion of the substrate covered by ink is 100% or less.

[0055] On the printed surface, the ink is dry. The amount of olefin copolymer in the ink is 1% by weight or more, more preferably 5% by weight or more, and more preferably 10% by weight or more, based on the weight of the ink. The amount of ethylene-acrylic copolymer in the ink is 99% by weight or less, more preferably 95% by weight or less, and more preferably 90% by weight or less, based on the weight of the ink.

[0056] The ink contains one or more conductive additives. The amount of conductive additives in the ink is preferably 0.5% by weight or more, more preferably 1% by weight or more, and more preferably 1.5% by weight or more, based on the weight of the dry ink. The amount of water in the ink is preferably 15% by weight or less, more preferably 10% by weight or less, and more preferably 5% by weight or less, based on the weight of the dry ink.

[0057] The substrate preferably has a thickness of 20 to 200 micrometers. The substrate preferably contains one or more polymers, and preferably the amount of polymer in the substrate is 50% or more, more preferably 75% or more, and more preferably 90% or more. The substrate may be a single polymer layer, or the substrate may be made of multiple polymer layers. If the substrate has multiple layers, any one layer may have the same composition as one or more of the other layers, or that one layer may have a composition different from all of the other layers. Any one layer may optionally contain one or more impact modifiers or other additives. Compounds may optionally be present between the layers to act, for example, as a binding layer and / or barrier layer.

[0058] The layer of the substrate in contact with the printing ink and the urethane coating composition of the present invention is referred to herein as the “upper” layer of the substrate. Preferably, the upper layer of the substrate comprises one or more polyolefins or one or more polyesters or a combination thereof. Preferably, the amount of polyolefin in the upper layer of the substrate is 50% by weight or more, more preferably 75% by weight or more, and more preferably 90% by weight or more. Suitable polyolefins include, for example, polypropylene, polyethylene, and mixtures thereof. Suitable forms of polyethylene include, for example, linear polyethylene homopolymer (HDPE), linear low-density polyethylene homopolymer, medium-density linear polyethylene homopolymer, low-density polyethylene homopolymer, and two or more blends thereof. Suitable polyesters include, for example, polyethylene terephthalate.

[0059] The cured polyurethane layer is expected to be durable. That is, it is expected to resist degradation caused by one or more of the following stressors: scratching, exposure to strong chemicals, crumpling, and heat.

[0060] If not protected in any way (e.g., by a durable coating or additional lamination), the printing substrate is expected to be highly susceptible to any of the stress factors mentioned above. In particular, when printing inks are exposed to any of these stress factors, they will suffer degradation in appearance and / or adhesion to the substrate. In the past, it was common to apply an additional polymer layer to the top of the printing surface (i.e., laminate an additional polymer layer on top of the printing surface) to protect the printing surface. Common additional polymers were polyethylene terephthalate and biaxially oriented polypropylene. Typically, the thickness of the additional polymer layer was 8 to 25 micrometers.

[0061] In contrast to previous implementations that involved laminating additional polymer layers, in the implementation of the present invention, the cured polyurethane layer provides a durable surface, and lamination of additional polymer layers is not required. Preferably, after the printed surface is coated by the implementation of the present invention, no additional polymer layer is laminated onto the coated printed surface.

[0062] Objects having the coated printed surface of the present invention can be used for any purpose. Preferred purposes include, for example, using objects having the coated printed surface of the present invention as part of a pouch or other packaging for containing food. Other purposes include, for example, household and personal care product packaging, protective films, printed liners, and labels. Preferably, when objects having the coated printed surface of the present invention are used for any purpose, no additional polymer layer is laminated onto the coated printed surface.

[0063] The following are examples of the present invention. Unless otherwise specified, the operations were performed at room temperature (approximately 23°C).

[0064] The following testing methods were used. (ASTM refers to the American Society of Testing and Materials (Conshohocken, PA, USA)).

[0065] The wetting of the liquid coating composition on the printing substrate was visually evaluated. A smoother and more uniform layer of the liquid coating composition was associated with better wetting performance. Bumps and depressions were considered evidence of a lack of uniformity in the liquid coating composition layer.

[0066] Scratch resistance was evaluated according to ASTM D7027-05. Temperature resistance was tested according to ASTM 1921. Gloss was evaluated according to ASTM D2457.

[0067] Chemical resistance was evaluated in the following test: 1 mL of simulated liquid was placed directly onto the coated ink on the printing film. At 0.5 hours, 4 hours, and 24 hours, the printing film was subjected to 5 cycles of tumbling and then flattened by hand. The film was then evaluated as follows: Good: The ink and coating remained on the surface without changing. Average condition: Some of the ink and varnish have randomly peeled off the film surface. Poor: The ink and coating have discolored and completely peeled off the film surface.

[0068] Temperature resistance was evaluated according to methods based on ASTM 1921 and ASTM D2457. The test result is the lowest temperature at which the sample begins to show obvious damage, such as dramatic shrinkage or film burning.

[0069] A multi-color printed image was created using various printing inks. The approximate composition of the inks before drying is thought to be as follows (weight percentage based on the weight of the printing inks): Less than 80% by weight of petroleum hydrocarbons Less than 15% by weight of olefin copolymer Approximately 2.5% by weight of conductive additive Approximately 3.5% by weight of dyes and pigments

[0070] The substrates used in the test are as follows: The symbol "μm" refers to micrometers. Percentages are weight percentages based on the weight of the layer. "PA" is polyamide. Polyamide can be co-extruded with polyethylene and / or maleic anhydride-modified polyethylene. I2 is the melt index, measured at 90°C using 2.16 kg, reported in grams per 10 minutes. D is the density in grams / cubic centimeter. [Table 1]

[0071] The following coating composition examples of the present invention were used.

[0072] Component A of Example 1 [Table 2]

[0073] To prepare composition A of Example 1, wax ester and trimethylolpropane were loaded into the reactor, followed by ethyl acetate. TDI was vacuum-loaded into the reactor, followed by vacuum-loading of the remaining ethyl acetate as a rinse solution. The batch was held at 70°C for 3 hours. The batch was then cooled to 55°C. The viscosity of the batch was measured. If the viscosity was less than 380 mPa*s (380 cP), trimethylolpropane was added to adjust the viscosity of the batch to 380 mPa*s (380 cP). If the viscosity was greater than 380 mPa*s (380 cP), or after adding additional trimethylolpropane, the reactor was cooled to 55°C. Corn oil was vacuum-loaded into the reactor. Cyclohexane was then added to the reactor, and the contents were held at 45°C and stirred for 45 minutes until the contents became clear. Subsequently, benzoyl chloride was vacuum-loaded into the reactor, and the contents were stirred for 15 minutes. The reaction composition A was then packaged for use.

[0074] Component A of Example 2 [Table 3]

[0075] To prepare composition A in Example 2, wax ester and trimethylolpropane were loaded into the reactor, followed by ethyl acetate. MDI was vacuum-loaded into the reactor, followed by the remaining ethyl acetate as a rinse solution. The batch was held at 70°C for 3 hours. The batch was then cooled to 55°C. Corn oil was vacuum-loaded into the reactor. Cyclohexane was then added to the reactor, and the contents were held at 45°C and stirred for 45 minutes until the contents became clear. Benzoyl chloride was then vacuum-loaded into the reactor, and the contents were stirred for 15 minutes. Composition A was then packaged for use.

[0076] Component B of Example 1 [Table 4]

[0077] To prepare reaction composition B of Example 1, TIPA was melted. Voranol 220-260 was vacuum-loaded into the reactor. The molten TIPA was vacuum-loaded into the reactor, and then Voranol 220-110N was vacuum-loaded. The vacuum line was rinsed with ethyl acetate, and the contents of the reactor were stirred at 75 RPM. Ethyl acetate was vacuum-loaded into the reactor. The contents of the reactor were cooled via a cooling jacket. After cooling, TDI was loaded into the reactor, and the vacuum line was rinsed with ethyl acetate. Because the reaction is exothermic, the contents of the reactor were cooled to a temperature of 75°C. The temperature inside the reactor was maintained at 75°C with stirring for 4 hours. The contents of the reactor were then cooled to 60°C, and the mixture of the defoamer and the remaining ethyl acetate was vacuum-loaded into the reactor. The contents were then stirred for 30 minutes. The reactor was then cooled to 50°C, and reaction composition B was packaged for use.

[0078] Component B of Example 2 [Table 5]

[0079] To prepare reaction composition B of Example 2, TIPA was melted. Voranol 220-260 was vacuum-loaded into the reactor. The molten TIPA was vacuum-loaded into the reactor, and then VORANOL 220-110N was vacuum-loaded. The vacuum line was rinsed with ethyl acetate, and the contents of the reactor were stirred at 75 RPM. Ethyl acetate was vacuum-loaded into the reactor. The contents of the reactor were cooled via a cooling jacket. After cooling, TDI was loaded into the reactor, and the vacuum line was rinsed with ethyl acetate. Because the reaction is exothermic, the contents of the reactor were cooled to a temperature of 75°C. The temperature inside the reactor was maintained at 75°C for 4 hours with stirring. Then, the contents of the reactor were cooled to 60°C, and a mixture of the defoamer, cellulose acetate butyrate, Modaflow, and the remaining ethyl acetate was vacuum-loaded into the reactor. The contents were then stirred at 60°C for 60 minutes. The reactor was then cooled to 50°C, and reaction composition B was packaged for use.

[0080] The following comparative example was used. [Table 6]

[0081] In the scratch resistance test, a substrate area was printed with a uniform block of a single color printing ink, and the printed area was tested. The result is the number of scratch cycles performed before the surface of the sample showed any visible damage. The best sample showed no damage after 50 cycles, but the test was stopped at 50 cycles. The results were as follows: [Table 7] The embodiments of the present invention showed better scratch resistance than all of the comparative examples.

[0082] Three different chemical reagents were used in the chemical resistance test. "Chlorine" = Liquid chlorine-containing disinfectant solution "Chlorine / detergent" = the same solution as "chlorine" with detergent added. "Liquid" = commercially available liquid multi-purpose household cleaning solution Three different chemical resistance times (standing times) were used: 0.5 hours, 4 hours, and 24 hours. The results were as follows: [Table 8] At 0.5 hours, all examples showed good performance. At 4 hours and 24 hours, the examples of the present invention showed better chemical resistance than all comparative examples.

[0083] The temperature resistance test was conducted as described above. The results were as follows: [Table 9] The embodiments of the present invention showed better temperature resistance than all of the comparative examples. The uncoated film showed damage at 75°C, and comparative examples C3, C4, and C5 showed damage at 125°C to 155°C, but the embodiments of the present invention showed no damage up to 175°C.

[0084] In the gloss test, the result was the gloss observed at a 60-degree angle. The results were as follows: [Table 10]

[0085] The embodiments of the present invention showed better gloss than all of the comparative examples. The present specification includes the following embodiments. Section 1. A process for manufacturing coated printing substrates, (a) To provide a printing substrate, wherein the substrate includes a surface present in one or more regions of the ink layer, (i) one or more olefin copolymers, (ii) One or more appearance additives selected from one or more pigments, one or more dyes, and mixtures thereof, (iii) To provide a product comprising one or more conductive additives, (b) Combining components A and B to form a urethane coating composition, Component A comprises a polyisocyanate prepolymer A1, and the polyisocyanate prepolymer A1 is a reaction product of a polyisocyanate monomer A1a and an isocyanate polyreactive compound A1b. Component B contains one or more polyol B1, The urethane coating composition has an isocyanate index greater than 0.9, and (c) A process comprising applying a layer of the urethane coating composition to the surface. Section 2. The process according to claim 1, wherein the polyol B1 comprises one or more polyurethane polyols B1PU, and the polyol B1PU comprises a reaction product of polyisocyanate monomer B1PUa and polyol B1PUb. Section 3. The process according to claim 1, wherein the olefin copolymer is selected from the group consisting of ethylene / acrylic copolymer, ethylene / ester copolymer, ethylene carbonyl copolymer, and mixtures thereof. Section 4. The process according to item 1, wherein component A comprises one or more fatty triglycerides. Section 5. The process according to item 1, wherein component A comprises one or more wax esters. Section 6. The process according to item 1, wherein component B further comprises one or more anti-blocking agents. Section 7. The process according to item 1, wherein component B further comprises one or more humectants. Section 8. The process according to item 1, wherein the substrate comprises polyethylene. Section 9. The process according to claim 1, wherein the isocyanate polyreactive compound A1b comprises one or more polyether polyols, one or more polyester polyols, or a mixture thereof. Section 10. The process according to claim 1, wherein the urethane coating composition has an isocyanate index of 0.9 to 1.6. Section 11. A coated printing substrate produced by the process described in Section 1.

Claims

1. A process for manufacturing coated printing substrates, (a) A step of providing a printing substrate, wherein the substrate has a surface on which one or more ink layer regions exist, and the ink is (i) one or more olefin copolymers, (ii) One or more appearance additives selected from one or more pigments, one or more dyes, and mixtures thereof, (iii) A step comprising one or more conductive additives, (b) A step of combining component A and component B to form a urethane coating composition, Component A comprises a polyisocyanate prepolymer A1, and the polyisocyanate prepolymer A1 is a reaction product of a polyisocyanate monomer A1a and an isocyanate polyreactive compound A1b. Component B contains one or more polyol B1, The urethane coating composition does not contain silica, and the urethane coating composition has an isocyanate index of 0.9 or higher. (c) A process comprising the step of applying a layer of the urethane coating composition to the surface.

2. The process according to claim 1, wherein the polyol B1 comprises one or more polyurethane polyols B1PU, and the polyol B1PU comprises a reaction product of a polyisocyanate monomer B1PUa and a polyol B1PUb.

3. The process according to claim 1, wherein the olefin copolymer is selected from the group consisting of ethylene / acrylic copolymer, ethylene / ester copolymer, ethylene carbonyl copolymer, and mixtures thereof.

4. The process according to claim 1, wherein component A comprises one or more fatty triglycerides.

5. The process according to claim 1, wherein component A comprises one or more wax esters.

6. The process according to claim 1, wherein component B further comprises one or more blocking inhibitors.

7. The process according to claim 1, wherein component B further comprises one or more organic blocking inhibitors.

8. The process according to claim 1, wherein component B further comprises one or more wetting agents.

9. The process according to claim 1, wherein the substrate includes polyethylene.

10. The process according to claim 1, wherein the urethane coating composition has an isocyanate index of 0.9 to 1.6.

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