Containers with printed labels

Abstract

To provide a container with a printed label that offers excellent scratch resistance, water resistance, and film adhesion without the need for heating through a baking process. [Solution] A printed label container having a base film, a printing layer, and an adhesive layer, wherein the printed label is attached via the adhesive layer, characterized in that a varnish layer is formed on the outermost surface of the base film opposite to the container.

Description

[Technical Field]

[0001] The present invention relates to a container with a printed label, and more particularly to a container with a printed label that is excellent in scratch resistance, water resistance, and film adhesion. [Background technology]

[0002] Methods for applying product names and various designs to containers for carbonated beverages, alcoholic beverages, other beverages, and various foods include laminating printed labels to the container, or directly printing on the curved surface of the can body using plate-based printing methods such as offset printing, or inkjet printing that does not use plates. Among these methods, laminating printed labels to the container is widely used because it offers greater design flexibility and processing freedom.

[0003] When laminating printed labels, the printed labels are wrapped around the surface of a metal can, laminated, and then baked in the final step to obtain containers with printed labels.

[0004] For example, Patent Document 1 describes a printed can in which a printed label consisting of at least an adhesive layer, a printing layer, and a transparent film layer is attached to at least the body of the outer surface of the can, with the adhesive layer facing the body of the can, and an inkjet printing layer and a finishing varnish layer are formed on the transparent film via a base layer. In this printed can, heating is performed after the formation of the finishing varnish layer to bake it.

[0005] Generally, the main purposes of baking are (1) to heat-cur the varnish composition and form a highly scratch-resistant and water-resistant film, and (2) to heat-cur the adhesive composition and increase its cohesive strength. Baking is usually performed using a hot air oven at a heating temperature of 180-200°C for 60-120 seconds. However, such baking complicates the production process and consumes a large amount of thermal energy. Therefore, if baking can be omitted, it will be possible to significantly increase production capacity and reduce energy costs.

[0006] To omit the baking process, it is conceivable to obtain a container with a printed label by accelerating the hardening of the varnish and adhesive layers by heat drying after coating the varnish composition or after coating the adhesive composition, and further hardening the varnish and adhesive layers by laminating after wrapping the printed label around the container. However, the heat drying after coating the varnish composition, the heat drying after coating the adhesive composition, and the laminating process have lower heating temperatures and shorter heating times compared to the baking process. Therefore, if the baking process is omitted in the above-mentioned Patent Document 1, there is a risk that the heat energy necessary for hardening the varnish and adhesive layers will be insufficient, resulting in insufficient hardening of the varnish and adhesive layers. In other words, problems may arise in the resulting container with a printed label, such as poor scratch resistance and water resistance of the printed label, and a tendency for delamination to occur between the surface of the container and the printed label. [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Japanese Patent Publication No. 2015-117030 [Overview of the project] [Problems that the invention aims to solve]

[0008] The object of the present invention is to obtain a container with a printed label that has excellent scratch resistance, water resistance, and film adhesion without the need for heating by baking. [Means for solving the problem]

[0009] According to the present invention, a container with a printed label is provided, wherein the printed label comprises at least a base film, a printing layer, and an adhesive layer, and the printed label is attached via the adhesive layer, characterized in that a varnish layer is formed on the outermost surface of the base film opposite to the container.

[0010] In the container with the printed label, it is preferable that the printed layer is a surface printed layer located between the varnish layer and the base film.

[0011] In the container with the printed label, it is preferable that a back-side printing layer is formed between the base film and the adhesive layer.

[0012] In the container with the printed label, it is preferable that the back surface printing layer contains inorganic pigments with a particle size of 0.05 μm to 200 μm.

[0013] In the container with the printed label, it is preferable that the inorganic pigment is a silver pigment, a white pigment, or a pearl pigment.

[0014] The container with the printed label is formed such that the varnish layer is made from varnish composition (i) or varnish composition (ii). The varnish composition (i) contains 50 to 80 parts by mass of polyester resin (A) having a number average molecular weight of 8,000 or more and less than 30,000 and a glass transition temperature of 40°C or more and less than 65°C, 10 to 40 parts by mass of polyester resin (B) having a number average molecular weight of 10,000 or more and less than 35,000 and a glass transition temperature of 50°C or more and less than 80°C, 1 to 10 parts by mass of block-type isocyanate (C) having a dissociation temperature of 110 to 150°C, and 0.1 to 1.0 parts by mass of silicon-modified acrylic resin (D). The varnish composition (ii) preferably contains 50 to 90 parts by mass of epoxy resin (E) having an epoxy equivalent of 1500 or more and less than 2500, 10 to 40 parts by mass of epoxy resin (F) having an epoxy equivalent of 2500 or more and less than 3500, 0.5 to 3.0 parts by mass of silicone-modified acrylic resin (G), and 1.0 to 10 parts by mass of isophorone diisocyanate polymer (H).

[0015] The container with the printed label preferably contains an adhesive composition forming the adhesive layer comprising: 10 to 40 parts by mass of polyester resin (I) having a number average molecular weight of 8,000 or more and less than 30,000 and a glass transition temperature of 40°C or more and less than 65°C; 1 to 10 parts by mass of polyester resin (J) having a number average molecular weight of 15,000 or more and less than 50,000 and a glass transition temperature of 5°C or more and less than 30°C; 40 to 60 parts by mass of titanium dioxide (K); 1 to 10 parts by mass of blocked isophorone diisocyanate (L); 1 to 10 parts by mass of blocked hexamethylene diisocyanate (M); and 1 to 5 parts by mass of novolac-type epoxy resin (N).

[0016] The container with the printed label preferably contains a hexamethylene diisocyanate polymer (O) in the varnish composition (i).

[0017] The container with the printed label preferably contains nylon resin beads (P) having an average particle size of 5 to 20 μm in either the varnish composition (i) or the varnish composition (ii).

[0018] The container with the printed label has a glossiness G of 50 or more at a reflection angle of 60°, which is obtained by measuring the outer surface of the container with the label. It is preferable that the parameter RSm / Ra, which is expressed by the average length RSm obtained by measuring the outer surface of the labeled container in accordance with the JIS-'01 standard and the arithmetic surface roughness Ra, is 150 or more.

[0019] In the container with the printed label, it is preferable that the varnish layer is in a fully cured state.

[0020] Preferably, the container with a printed label is a seamless can.

[0021] Further, according to the present invention, there is provided a method for producing a container with a printed label, the method comprising: a step of forming a surface printing layer on one surface of a base film; a step of forming a varnish layer on the surface printing layer; a step of forming a back printing layer on the other surface of the base film; a step of forming an adhesive layer on the back printing layer; a temporary heating step of semi-curing the varnish layer to produce a printed label; and a laminating step of attaching the printed label to an outer surface of a container.

[0022] In the method for producing a container with a printed label, using a printing press having n printing units, a surface printing layer is formed on a base film by the 1st to (m-1)th printing units, after a varnish layer is formed on the surface printing layer by the m-th printing unit, the base film on which the surface printing layer and the varnish layer have been formed is inverted using an inverter, a back printing layer is formed on the back surface of the base film on the side opposite to the surface on which the surface printing layer and the varnish layer have been formed by the (m+1)th to nth printing units, and then an adhesive layer is formed on the back printing layer, Preferably, m, which is the number of the printing unit that forms the varnish layer, is an integer of any one from 2 to (n-1).

[0023] Further, according to the present invention, there is provided a method for producing a container with a printed label, the method comprising: a step of forming a back printing layer on one surface of a base film; a step of forming a varnish layer on the other surface of the base film; a step of forming an adhesive layer on the back printing layer; a temporary heating step of semi-curing the varnish layer to produce a printed label; and a laminating step of attaching the printed label to an outer surface of a container.

[0024] The method for manufacturing the container with the printed label is preferably to use a printing machine having n printing units to form a back-side printed layer on a base film using the 1st to (n-1)th printing units, then to use an inversion machine to invert the base film on which the back-side printed layer has been formed, to form a varnish layer on the side of the base film on which the back-side printed layer has not been formed using the nth printing unit, to use an inversion machine to invert the base film on which the back-side printed layer has been formed, and then to form an adhesive layer on the back-side printed layer.

[0025] The method for manufacturing the container with the printed label preferably involves using a printing machine having n printing units to form a varnish layer on a base film with the first printing unit, inverting the base film with the varnish layer using an inverting machine, then forming a backside printing layer on the side where the varnish layer is not formed with the second to nth printing units, and then forming an adhesive layer on the backside printing layer.

[0026] The method for manufacturing the container with the printed label preferably includes a heating step after the lamination step, and the varnish layer after the heating step is fully cured.

[0027] In the method for manufacturing the container with the printed label, it is preferable that the varnish layer or adhesive layer is formed by gravure printing. [Effects of the Invention]

[0028] In this invention, a container with a printed label that has excellent scratch resistance, water resistance, and film adhesion can be obtained without heating by baking. Furthermore, since the container with the printed label of this invention does not require heating by baking, it is also excellent in terms of manufacturing efficiency and energy cost. [Brief explanation of the drawing]

[0029] [Figure 1] A diagram showing an example of the layer structure of a printed label container according to the present invention. [Figure 2] A diagram showing another example of the layer structure of the printed label container of the present invention. [Modes for carrying out the invention]

[0030] <Container with printed label 1, printed label 2> The printed label container 1 of the present invention is characterized in that a printed label 2 comprising a base film 3, a printing layer 4, and an adhesive layer 6 is attached to the container via the adhesive layer 6, and a varnish layer 5 is formed on the outermost surface of the base film 3 opposite to the container. Figures 1 and 2 show the layer configuration of the printed label container 1 of the present invention. In the example shown in Figure 1, the printed label 2 comprising a varnish layer 5, a surface printing layer 4a, a base film 3, a back printing layer 4b, and an adhesive layer 6 in that order from the outer side is attached to the outer surface of the container 7 via the adhesive layer 6. In the example shown in Figure 2, the printed label 2 comprising a varnish layer 5, a base film 3, a back printing layer 4b, and an adhesive layer 6 in that order from the outer side is attached to the outer surface of the container 7 via the adhesive layer 6.

[0031] <Base film 3> The base film 3 of the printed label container 1 of the present invention is a film that serves as the base for the printed label 2. This base film 3 is generally a film formed from a thermoplastic resin, and its material is a known thermoplastic resin, for example, polyolefins such as low-density polyethylene, high-density polyethylene, polypropylene, poly-1-butene, poly-4-methyl-1-pentene, or random or block copolymers of α-olefins such as ethylene, propylene, 1-butene, and 4-methyl-1-pentene, cyclic olefin resins such as cyclic olefin copolymers and cyclic olefin polymers, ethylene-vinyl acetate copolymers, ethylene-vinyl alcohol copolymers, ethylene-vinyl chloride copolymers, and other ethylene-vinyl compound copolymers, polystyrene, acrylonitrile-styrene copolymers, ABS, and α-methyl Examples include styrene-styrene copolymers and other styrene-based resins, polyvinyl chloride, polyvinylidene chloride, vinyl chloride-vinylidene chloride copolymers, methyl polyacrylate, polymethyl methacrylate and other polyvinyl compounds, polyamides such as nylon 6, nylon 6-6, nylon 6-10, nylon 11, and nylon 12, polyesters such as polyethylene terephthalate (PET), polybutylene terephthalate (PBT), and polyethylene naphthalate (PEN), polycarbonates, polyphenylene oxide, and other biodegradable resins such as fluororesins, allyl resins, polyurethane resins, cellulose resins, polysulfone resins, polyethersulfone resins, ketone resins, amino resins, or polylactic acid. Furthermore, blends of these resins and resins modified by copolymerization as appropriate (for example, acid-modified olefin resins) are also included. Among these, polyester resins such as polyethylene terephthalate are preferably used because they have good heat resistance and are insoluble in organic solvents.

[0032] The base film 3 may be uniaxially or biaxially stretched, and a biaxially stretched film is particularly suitable for use.

[0033] The thickness of the base film 3 of the printed label container 1 of the present invention cannot be specified in general terms as it varies depending on the size of the container 7, but for a typical metal can for beverages, it is 8 to 20 μm. If it is excessively thick, when the printed label 2 is laminated to the metal can, the thickness of the overlapping portion will become thick, which may impair the appearance of the printed label container 1.

[0034] <Print layer 4> The printed layer 4 of the printed label container 1 of the present invention serves to enhance the color and design of the printed label container 1.

[0035] In the printed label container 1 of the present invention, the printed layer 4 is preferably a surface printed layer 4a located between the varnish layer 5 and the base film 3. When the printed layer 4 is a surface printed layer 4a, the varnish layer 5 can be formed on top of the printed layer without inverting the film after the surface printed layer 4a has been formed, thus simplifying the manufacturing process.

[0036] Furthermore, it is preferable that a back-side printing layer 4b is formed between the base film 3 and the adhesive layer 6. By forming the back-side printing layer 4b, a container 1 with a printed label that has excellent color can be made.

[0037] The pigment used in the printing layer 4 can be any conventionally known pigment, but from the viewpoint of suppressing elution into the adhesive layer 6, an inorganic pigment is preferred. Furthermore, the particle size of the pigment used in the printing layer 4 is preferably 0.05 to 200 μm, and more preferably 0.05 to 30 μm. If the particle size of the pigment is less than 0.05 μm, the color tone of the printing layer 4 will be insufficient. On the other hand, if the particle size of the pigment is greater than 200 μm, the pigment particles may protrude from the printing layer 4, potentially affecting the adhesive layer 6 and worsening the adhesion.

[0038] Furthermore, it is preferable that the inorganic pigment used in the printing layer 4 is a silver pigment, a white pigment, or a pearl pigment. By using such pigments, the glossiness of the outer surface of the printed label container 1 of the present invention can be improved.

[0039] The type of ink used in the printing layer 4 of the printed label container 1 of the present invention can be any conventionally known ink. Specifically, from the viewpoint of water resistance, printability, and pigment dispersibility, it is preferable to use a thermosetting ink with a thermosetting resin such as acrylic, urethane, or polyester as the base resin.

[0040] The printed layer 4 of the printed label container 1 of the present invention may be solid print, or the printed layer 4 may be partially formed. Furthermore, the back printed layer 4b is preferably solid print.

[0041] <5 layers of varnish> The varnish layer 5 of the printed label container 1 of the present invention is the outermost layer when the printed label 2 is laminated to the container 7, and plays a role in protecting the base film 3 and the printed layer 4. The varnish layer 5 of the printed label container 1 of the present invention is formed from varnish composition (i) or varnish composition (ii), and varnish composition (i) is formed from 50 to 80 parts by mass of polyester resin (A) having a number average molecular weight of 8,000 or more and less than 30,000 and a glass transition temperature of 40°C or more and less than 65°C, 10 to 40 parts by mass of polyester resin (B) having a number average molecular weight of 10,000 or more and less than 35,000 and a glass transition temperature of 50°C or more and less than 80°C, and block-type isocyanate having a dissociation temperature of 110 to 150°C The varnish composition (ii) preferably contains 1 to 10 parts by mass of (C) and 0.1 to 1.0 parts by mass of a silicone-modified acrylic resin (D), and preferably contains 50 to 90 parts by mass of an epoxy resin (E) with an epoxy equivalent of 1500 or more and less than 2500, 10 to 40 parts by mass of an epoxy resin (F) with an epoxy equivalent of 2500 or more and less than 3500, 0.5 to 3.0 parts by mass of a silicone-modified acrylic resin (G), and 1.0 to 10 parts by mass of an isophorone diisocyanate polymer (H).

[0042] [Varnish composition (i)] The varnish composition (i) for the printed label container 1 of the present invention contains specific amounts of two types of polyester resins (A) and polyester resin (B) having different number-average molecular weight ranges and glass transition temperature (Tg) ranges, respectively, a block-type isocyanate (C) having a specific dissociation temperature range, and a silicon-modified acrylic resin (D).

[0043] The polyester resin (A) used in the varnish composition (i) of the printed label container 1 of the present invention preferably has a number average molecular weight in the range of 8,000 or more and less than 30,000, and more preferably 12,000 or more and less than 24,000. If the number average molecular weight is less than 8,000, the reactivity with isocyanate tends to decrease, resulting in insufficient crosslinking, and depending on the heating conditions, there is a concern that the water resistance and scratch resistance may decrease. On the other hand, if the number average molecular weight is 30,000 or more, the viscosity of the solution when it is made into a paint becomes too high, which may adversely affect the coatability and workability.

[0044] The above polyester resin (A) is preferably one with a glass transition temperature of 40°C or higher and less than 65°C, and more preferably one with a glass transition temperature of 45°C or higher and less than 60°C. If the glass transition temperature is less than 40°C, blocking with the adhesive layer 6 on the back may occur when the coated film is wound up. On the other hand, if the glass transition temperature is 65°C or higher, when an overlap portion is formed, the adhesion with the adhesive layer 6 may decrease, and overlap defects may occur.

[0045] The varnish composition (i) of the printed label container 1 of the present invention preferably contains 50 to 80 parts by mass of polyester resin (A) per 100 parts by mass (on a solid content basis) of varnish composition (i), and more preferably 60 to 70 parts by mass. If the amount of polyester resin (A) is less than 50 parts by mass, the Tg of the varnish layer 5 is too high, which tends to reduce the overlap suitability. On the other hand, if the amount of polyester resin (A) exceeds 80 parts by mass, the Tg of the varnish layer 5 is too low, which may lead to a decrease in blocking properties.

[0046] The polyester resin (B) is preferably one with a number average molecular weight of 10,000 or more and less than 35,000, and more preferably one with a number average molecular weight of 15,000 or more and less than 25,000. If the number average molecular weight is less than 10,000, the molecular weight of the varnish layer 5 when crosslinked may be insufficient, which may reduce processability. On the other hand, if the number average molecular weight is 35,000 or more, compatibility with other resins decreases, and scratch resistance and water resistance tend to decrease.

[0047] The above polyester resin (B) is preferably one with a glass transition temperature of 50°C or higher and less than 80°C, and more preferably one with a glass transition temperature of 55°C or higher and less than 75°C. If the glass transition temperature is below 50°C, the scratch resistance after curing of the varnish layer 5 may decrease. On the other hand, if the glass transition temperature is 80°C or higher, the overlap suitability of the varnish layer 5 tends to decrease.

[0048] The varnish composition (i) for the printed label container 1 of the present invention preferably contains 10 to 40 parts by mass of polyester resin (B) per 100 parts by mass (on a solid content basis) of varnish composition (i), and more preferably 25 to 35 parts by mass. If the amount of polyester resin (B) is less than 10 parts by mass, the Tg of the varnish layer 5 tends to be too high, resulting in reduced overlap suitability. On the other hand, if the amount of polyester resin (B) exceeds 40 parts by mass, the Tg of the varnish layer 5 tends to be too low, resulting in reduced blocking properties.

[0049] Both polyester resins (A) and (B) can be those obtained by esterifying a polybasic acid component with a polyhydric alcohol component.

[0050] As polybasic acid components, one or more dibasic acids such as phthalic anhydride, isophthalic acid, terephthalic acid, succinic acid, fumaric acid, adipic acid, azelaic acid, sebacic acid, and dimer acid, and lower alkyl esters of these acids are mainly used. If necessary, monobasic acids such as benzoic acid, crotonic acid, and pt-butylbenzoic acid, and polybasic acids of trivalent or higher valencies such as trimellitic anhydride, methylcyclohexentricarboxylic acid, and pyromellitic anhydride are used in combination.

[0051] As polyhydric alcohol components, dihydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, 1,4-butanediol, neopentyl glycol, 3-methylpentanediol, 1,4-hexanediol, 1,6-hexanediol, and cyclohexanedimethanol are mainly used, and if necessary, trihydric or higher polyhydric alcohols such as glycerin, trimethylolethane, trimethylolpropane, and pentaerythritol can be used in combination. These polyhydric alcohols can be used alone or in mixtures of two or more.

[0052] The block-type isocyanate (C) used in the printed label container 1 of the present invention preferably has a dissociation temperature of 110 to 150°C, and more preferably 120 to 140°C. As a result, the block-free isocyanate reacts with the hydroxyl groups of the polyester resin at room temperature, and the block-type isocyanate reacts during heating for film drying and lamination, causing the coating to harden in stages. This relieves the internal stress of the coating and makes it possible to maintain strong adhesion with the base film 3.

[0053] The block-type isocyanate (C) can be any common type within the aforementioned dissociation temperature range. A polyfunctional organic polyisocyanate having a bonding form such as an adduct obtained by adding 3 moles of organic diisocyanate to 1 mole of trimethylolpropane, a burette obtained by reacting 3 moles of organic diisocyanate with 1 mole of water, or an isocyanurate obtained by polymerization of 3 moles of organic diisocyanate can be used. Alternatively, a polyurethane polyisocyanate compound obtained by reacting a polyisocyanate with a polyester polyol, a polyether polyol, or, if necessary, with a low molecular weight polyol can be used. Examples of these aromatic polyisocyanates include 2,4'-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyle diisocyanate, tetraalkyldiphenylmethane diisocyanate, dialkyldiphenylmethane diisocyanate, 1,3-phenylenediisocyanate, polymeric diphenylmethane diisocyanate, tolylene diisocyanate (2,4- or 2,6-tolylene diisocyanate or its compounds), 4,4'-toluidine diisocyanate, 4,4'-diphenyl ether diisocyanate, 1,5-naphthylene diisocyanate, and naphthalene diisocyanate.

[0054] Examples of aliphatic polyisocyanates include hexamethylene diisocyanate, trimethylene diisocyanate, trimethylhexamethylene diisocyanate (2,2,4- or 2,4,4-), lysine diisocyanate, xylylene diisocyanate, 1,2-propylene diisocyanate, butylene diisocyanate, 1,2-butylene diisocyanate, 2,3-butylene diisocyanate, 1,3-butylene diisocyanate, and 1,5-pentamethylene diisocyanate.

[0055] Examples of alicyclic polyisocyanates include 1,3-cyclopentane diisocyanate, 1,3-cyclopentene diisocyanate, cyclohexane diisocyanate (1,3- or 1,4-), 3-isocyanate methyl-3,5,5-trimethylcyclohexyl isocyanate, methylcyclohexane diisocyanate (-2,4- or -2,6-), and norbornane diisocyanate.

[0056] Blocking agents that block the isocyanate group of the above polyisocyanate compound include phenols such as phenol, cresol (o,m,p), and xylenol; alcohols such as methanol, ethanol, n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, and isobutyl alcohol; oximes such as acetooxime, methyl ethyl ketone oxime, acetaldehyde, formaldehyde, diacetylmonoxime, and cyclohexaneoxime; active methylene compounds such as methyl acetoacetate, ethyl acetoacetate, and acetylacetone; and lactams such as ε-caprolactam, δ-valerolactam, γ-butyrolactam, and β-propiolactam.

[0057] The varnish composition (i) of the printed label container 1 of the present invention preferably contains 1 to 10 parts by mass of block-type isocyanate (C) per 100 parts by mass (on a solid content basis) of varnish composition (i), and more preferably 3 to 7 parts by mass. If the amount of block-type isocyanate (C) is less than 1 part by mass, the degree of crosslinking of the varnish layer 5 is low, and water resistance and scratch resistance tend to decrease. On the other hand, if the amount of block-type isocyanate (C) exceeds 10 parts by mass, the functional groups of the polyester resin and the formation of the allophanate skeleton after the urethane reaction result in a rigid structure, which tends to reduce processability.

[0058] The silicone-modified acrylic resin (D) used in the varnish composition (i) of the printed label container 1 of the present invention is used to prevent scratches during the can manufacturing and transport processes and to impart slipperiness and abrasion resistance to the varnish layer 5. This silicone-modified acrylic resin (D) exhibits slipperiness and abrasion resistance because the silicone groups are oriented on the surface of the coating film, while the acrylic resin reacts with isocyanate groups and is stably arranged in the coating film, resulting in less loss during retort processing and other processes. This silicone-modified acrylic resin (D) is a graft polymer synthesized by copolymerization of a silicone monomer and an acrylic monomer, and can be manufactured using known techniques.

[0059] The varnish composition (i) for the printed label container 1 of the present invention preferably contains 0.1 to 1.0 parts by mass of silicone-modified acrylic resin (D) per 100 parts by mass (in terms of solid content) of varnish composition (i), and more preferably 0.3 to 0.7 parts by mass. If the amount of silicone-modified acrylic resin (D) is less than 0.1 parts by mass, the slipperiness and abrasion resistance of the varnish layer 5 may be insufficient. On the other hand, if the amount of silicone-modified acrylic resin (D) exceeds 1.0 part by mass, there is a concern that it may impede the adhesion between the varnish layer 5 and the adhesive layer 6 when they overlap.

[0060] Furthermore, it is preferable that the varnish composition (i) of the printed label container 1 of the present invention contains a hexamethylene diisocyanate polymer (O). By containing the hexamethylene diisocyanate polymer (O), the curing reaction with the polyester resin proceeds more easily even at low temperatures, improving the scratch resistance of the varnish layer 5 and the adhesion strength between the varnish layer 5 and the base film 3.

[0061] [Varnish composition (ii)] The varnish composition (ii) for the printed label container 1 of the present invention contains specific amounts of two epoxy resins (E) and epoxy resin (F) having different epoxy equivalent ranges, a silicone-modified acrylic resin (G), and an isophorone diisocyanate polymer (H).

[0062] The epoxy resin (E) used in the varnish composition (ii) of the printed label container 1 of the present invention preferably has an epoxy equivalent of 1500 or more and less than 2500, and more preferably has an epoxy equivalent of 1800 or more and less than 2300. If the epoxy equivalent of the epoxy resin (E) is less than 1500, the reactivity with isocyanate tends to decrease, resulting in insufficient crosslinking, which may reduce water resistance and scratch resistance. On the other hand, if the epoxy equivalent of the epoxy resin (E) is 2500 or more, the viscosity of the solution when it is made into a paint may become too high, which may adversely affect the paintability and workability.

[0063] The varnish composition (ii) for the printed label container 1 of the present invention preferably contains 50 to 90 parts by mass of epoxy resin (E) per 100 parts by mass (in terms of solid content) of varnish composition (ii), and more preferably 60 to 75 parts by mass. If the amount of epoxy resin (E) is less than 50 parts by mass, adhesion strength with the base film 3 may not be obtained. On the other hand, if the amount of epoxy resin (E) exceeds 90 parts by mass, the varnish layer 5 will lack flexibility and have poor processability.

[0064] The epoxy resin (F) used in the varnish composition (ii) of the printed label container 1 of the present invention preferably has an epoxy equivalent of 2500 or more and less than 3500, and more preferably has an epoxy equivalent of 2700 or more and less than 3300. If the epoxy equivalent of the epoxy resin (F) is less than 2500, the molecular weight of the coating film when crosslinked may be insufficient, which may reduce processability. On the other hand, if the epoxy equivalent of the epoxy resin (F) is 3500 or more, compatibility with other resins tends to decrease, and water resistance and scratch resistance tend to decrease.

[0065] The varnish composition (ii) for the printed label container 1 of the present invention preferably contains 10 to 40 parts by mass of epoxy resin (F) per 100 parts by mass (in terms of solid content) of varnish composition (ii), and more preferably 25 to 35 parts by mass. If the amount of epoxy resin (F) is less than 10 parts by mass, the water resistance may decrease. On the other hand, if the amount of epoxy resin (F) exceeds 40 parts by mass, the viscosity of the solution when it is made into a paint may become too high, which may adversely affect the paintability and workability.

[0066] The epoxy resin (E) and epoxy resin (F) described above are preferably bisphenol A type epoxy resin or bisphenol F type epoxy resin, with bisphenol A type epoxy resin being particularly preferred.

[0067] The above-mentioned bisphenol A type epoxy resin may be, for example, a resin obtained by condensing epichlorohydrin and bisphenol to a high molecular weight in the presence of an acid or alkali catalyst (such as a phosphoric acid or ammonium salt catalyst) as needed, or a resin obtained by polyaddition reaction between epoxy resin and bisphenol.

[0068] The silicone-modified acrylic resin (G) used in the varnish composition (ii) of the printed label container 1 of the present invention is used to prevent scratches during the can manufacturing and transport processes and to impart slipperiness and abrasion resistance to the coating film. The silicone-modified acrylic resin (G) can be the same as the silicone-modified acrylic resin (D) used in the varnish composition (i).

[0069] The varnish composition (ii) for the printed label container 1 of the present invention preferably contains 0.5 to 3.0 parts by mass of the silicone-modified acrylic resin (G) per 100 parts by mass (in terms of solid content) of the varnish composition (ii), and more preferably 0.7 to 2.0 parts by mass. If the amount of silicone-modified acrylic resin (G) is less than 0.5 parts by mass, the slipperiness may be insufficient. On the other hand, if the amount of silicone-modified acrylic resin (G) exceeds 3.0 parts by mass, there is a concern that it may impede adhesion with the adhesive layer 6 when overlapped.

[0070] The isophorone diisocyanate polymer (H) used in the varnish composition (ii) of the printed label container 1 of the present invention is used for the purpose of imparting low-temperature curability.

[0071] The varnish composition (ii) for the printed label container 1 of the present invention preferably contains 1.0 to 10 parts by mass of isophorone diisocyanate polymer (H) per 100 parts by mass of varnish composition (ii), and more preferably 3 to 7 parts by mass. If the amount of isophorone diisocyanate polymer (H) is less than 1.0 part by mass per 100 parts by mass of varnish composition (ii), the degree of crosslinking of the varnish layer 5 is low, and the curing of the varnish layer 5 at low temperatures becomes insufficient. On the other hand, if the amount of isophorone diisocyanate polymer (H) is more than 10 parts by mass, unreacted functional groups react with moisture in the air and tend to take on a rigid structure, resulting in reduced processability.

[0072] The varnish composition (i) or varnish composition (ii) of the printed label container 1 of the present invention preferably contains nylon resin beads (P) with an average particle size of 5 to 20 μm, from the viewpoint of providing scratch resistance. If the average particle size is less than 5 μm, the scratch resistance of the varnish layer 5 will be insufficient. On the other hand, if the average particle size is greater than 20 μm, there is a risk of poor transfer during gravure printing.

[0073] The varnish compositions (i) and (ii) of the printed label container 1 of the present invention may contain, as appropriate, lubricants, defoamers, leveling agents, pigments, etc. In addition, other curing agents such as urea resin, melamine resin, benzoguanamine resin, isocyanate resin, and polyamide resin may be used in combination as curing aids, and the appropriate one can be used depending on the drying conditions and lamination conditions.

[0074] The dry film thickness of the varnish layer 5 of the printed label container 1 of the present invention is preferably 1.0 to 5.0 μm, and more preferably in the range of 2.0 to 4.0 μm. If the film thickness is less than 1.0 μm, scratches can easily reach the base film 3, and the base film 3 cannot be adequately protected. On the other hand, if the film thickness is greater than 5.0 μm, the transparency of the varnish layer 5 tends to decrease.

[0075] The varnish layer 5 of the printed label container 1 of the present invention is preferably fully cured. After laminating the printed label 2 to the container 7, the varnish layer 5 is fully cured by a post-heating process described later. This further improves scratch resistance and water resistance. In this post-heating process performed after the lamination process, it is not necessary to heat the temperature as high as in conventional baking processes, and the energy cost for fully curing the varnish layer 5 is reduced.

[0076] <Adhesive layer 6> The adhesive layer 6 of the printed label container 1 of the present invention is a layer provided for laminating the printed label 2 to the container 7. Preferably, the adhesive composition forming the adhesive layer 6 contains specific amounts of two types of polyester resin (I) and polyester resin (J) having different number-average molecular weight ranges and glass transition temperature (Tg) ranges, respectively, titanium dioxide (K), blocked isophorone diisocyanate (L), blocked hexamethylene diisocyanate (M), and novolac-type epoxy resin (N).

[0077] The polyester resin (I) used in the adhesive composition of the printed label container 1 of the present invention preferably has a number average molecular weight of 8,000 or more and less than 30,000, and more preferably 12,000 or more and less than 25,000. If the number average molecular weight is less than 8,000, the reactivity with isocyanate tends to decrease, resulting in insufficient crosslinking and a tendency for reduced water resistance. On the other hand, if the number average molecular weight is 30,000 or more, the viscosity of the solution when it is made into a paint may become too high, potentially adversely affecting the paintability and workability.

[0078] The polyester resin (I) used in the adhesive composition of the printed label container 1 of the present invention preferably has a glass transition temperature of 40°C or higher and less than 65°C, and more preferably 50°C or higher and less than 60°C. When the glass transition temperature is less than 40°C, blocking with the varnish layer 5 tends to occur when the coated film is wound up. On the other hand, when the glass transition temperature is 65°C or higher, the adhesive layer 6 tends to melt and soften less easily during lamination, and the laminating properties tend to decrease.

[0079] In the printed label container 1 of the present invention, the polyester resin (I) is preferably 10 to 40 parts by mass, and more preferably 25 to 38 parts by mass, per 100 parts by mass (in terms of solid content) of the adhesive composition. If the amount of polyester resin (I) is less than 10 parts by mass, the Tg of the adhesive layer 6 is too high, which tends to reduce the laminating properties. On the other hand, if the amount of polyester resin (I) exceeds 40 parts by mass, the Tg of the adhesive layer 6 is too low, which tends to cause the adhesive layer 6 to soften too much when heated, making it prone to trapping bubbles and other debris.

[0080] The polyester resin (J) used in the adhesive composition of the present invention preferably has a number average molecular weight of 15,000 or more and less than 50,000, and more preferably 20,000 or more and less than 40,000. If the number average molecular weight is less than 15,000, the molecular weight of the adhesive layer 6 when crosslinked may be insufficient, which may reduce processability. On the other hand, if the number average molecular weight is 50,000 or more, the viscosity of the solution when it is made into a paint may become too high, which may adversely affect the coatability and workability.

[0081] The polyester resin (J) used in the adhesive composition of the printed label container 1 of the present invention preferably has a glass transition temperature of 5°C or higher and less than 30°C, and more preferably 10°C or higher and less than 25°C. When the glass transition temperature is less than 5°C, blocking with the varnish layer 5 tends to occur when the coated film is wound up. On the other hand, when the glass transition temperature is 30°C or higher, the adhesive layer 6 tends to melt and soften less easily during lamination, and the laminating properties tend to decrease.

[0082] The adhesive composition for the printed label container 1 of the present invention preferably contains 1 to 10 parts by mass of polyester resin (J) per 100 parts by mass of the adhesive composition (on a solid content basis), and more preferably 3 to 8 parts by mass. If the amount of polyester resin (J) is less than 1 part by mass per 100 parts by mass of the adhesive composition (on a solid content basis), the Tg of the adhesive layer 6 tends to be too high, resulting in reduced lamination properties. If the amount of polyester resin (J) exceeds 10 parts by mass, the Tg of the adhesive layer 6 is too low, causing the adhesive layer 6 to soften too much when heated, making it prone to trapping bubbles and other debris.

[0083] The titanium dioxide (K) used in the adhesive composition of the printed label container 1 of the present invention can be suitably used as a white pigment to conceal the dull appearance color characteristic of steel plates. Generally, a thick base film 3 kneaded with titanium dioxide or the like is used as a means of imparting opacity to metal cans, but by incorporating titanium dioxide or the like into the adhesive, opacity can be achieved, enabling the base film 3 to be made thinner, and in some cases a transparent film can be used, leading to a significant cost reduction.

[0084] The titanium dioxide (K) used in the adhesive composition of the printed label container 1 of the present invention is preferably produced by the sulfuric acid method, has a particle size in the range of 0.1 to 0.4 μm, and is treated with silica or alumina as a surface treatment agent. Titanium dioxide produced by the chlorine method generally has a higher Mohs hardness than titanium dioxide produced by the sulfuric acid method, and tends to reduce workability by easily wearing down the doctor blade during printing. If the particle size of titanium dioxide is 0.1 μm or larger, the opacity tends not to decrease, and if it is 0.4 μm or smaller, it tends not to cause inhibition of the paste.

[0085] The adhesive composition for the printed label container 1 of the present invention preferably contains 40 to 60 parts by mass of titanium dioxide (K) per 100 parts by mass of the adhesive composition (based on solid content), and more preferably 42 to 50 parts by mass. If the amount of titanium dioxide (K) is less than 40 parts by mass per 100 parts by mass of the adhesive composition (based on solid content), the opacity may be insufficient. On the other hand, if the amount of titanium dioxide (K) is more than 60 parts by mass, it tends to easily cause inhibition of meat mixing.

[0086] The adhesive composition of the printed label container 1 of the present invention preferably contains block-type isophorone diisocyanate (L) for the purpose of promoting low-temperature curing of the adhesive layer 6.

[0087] The amount of block-type isophorone diisocyanate (L) used in the adhesive composition of the printed label container 1 of the present invention is preferably 1 to 10 parts by mass, and more preferably 3 to 8 parts by mass, per 100 parts by mass (solid content) of the adhesive composition. If the amount of block-type isophorone diisocyanate (L) is less than 1 part by mass per 100 parts by mass (solid content) of the adhesive composition, the curing of the adhesive layer 6 at low temperatures will be insufficient. On the other hand, if the amount of block-type isophorone diisocyanate (L) is more than 10 parts by mass, the processability tends to decrease because a rigid structure is formed due to the functional groups of the polyester resin and the formation of the allophanate skeleton after the urethane reaction.

[0088] The adhesive composition of the printed label container 1 of the present invention preferably contains block-type hexamethylene diisocyanate (M) for the purpose of promoting low-temperature curing of the adhesive layer 6.

[0089] The adhesive composition for the printed label container 1 of the present invention preferably contains 1 to 10 parts by mass, and more preferably 3 to 8 parts by mass, of block-type hexamethylene diisocyanate (M) per 100 parts by mass (solid content) of the adhesive composition. If the amount of block-type hexamethylene diisocyanate (M) is less than 1 part by mass per 100 parts by mass (solid content) of the adhesive composition, the curing of the adhesive layer 6 at low temperatures will be insufficient. On the other hand, if the amount of block-type hexamethylene diisocyanate (M) is more than 10 parts by mass, the processability tends to decrease because a rigid structure is formed due to the functional groups of the polyester resin and the formation of the allophanate skeleton after the urethane reaction.

[0090] The adhesive composition of the printed label container 1 of the present invention preferably contains a novolac-type epoxy resin (N) for the purpose of promoting low-temperature curing of the adhesive layer 6.

[0091] The novolac-type epoxy resin (N) used in the adhesive composition of the printed label container 1 of the present invention is preferably 1 to 5 parts by mass, and more preferably 2 to 4 parts by mass, per 100 parts by mass (solid content) of the adhesive composition. If the amount of novolac-type epoxy resin (N) is less than 1 part by mass per 100 parts by mass (solid content) of the adhesive composition, the low-temperature softening properties of the adhesive film will be poor, and lamination defects may occur. On the other hand, if the amount of novolac-type epoxy resin (N) is more than 5 parts by mass, blocking with the varnish layer 5 tends to occur when the coated film is wound up.

[0092] There are no particular limitations on the diluent solvents that can be used for the varnish composition (i), varnish composition (ii), and adhesive composition of the printed label container 1 of the present invention. Examples include aromatic hydrocarbons such as toluene, xylene, Solvesso #100, and Solvesso #150; aliphatic hydrocarbons such as hexane, heptane, octane, and decane; and various ester-based organic solvents such as methyl acetate, ethyl acetate, isopropyl acetate, butyl acetate, amyl acetate, ethyl formate, and butyl propionate. Furthermore, examples of water-miscible organic solvents include alcohol-based solvents such as methanol, ethanol, propanol, and butanol; ketone-based solvents such as acetone, methyl ethyl ketone, and cyclohexanone; and glycol ether-based solvents such as ethylene glycol (mono, di)methyl ether, ethylene glycol (mono, di)ethyl ether, ethylene glycol monopropyl ether, ethylene glycol monoisopropyl ether, monobutyl ether, diethylene glycol (mono, di)methyl ether, diethylene glycol (mono, di)ethyl ether, diethylene glycol monoisopropyl ether, diethylene glycol monobutyl ether, triethylene glycol (mono, di)methyl ether, propylene glycol (mono, di)methyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and dipropylene glycol (mono, di)methyl ether. Of these, methyl ethyl ketone, ethyl acetate, or mixtures thereof are usually preferred.

[0093] The adhesive composition of the printed label container 1 of the present invention may contain, as appropriate, lubricants, defoamers, leveling agents, pigments, etc., as needed. In addition, other curing agents such as urea resin, melamine resin, benzoguanamine resin, isocyanate resin, and polyamide resin may be used in combination as curing aids, and the appropriate one can be used depending on the heating and drying conditions and lamination conditions.

[0094] The dry thickness of the adhesive layer 6 of the printed label container 1 of the present invention is 0.1 to 10 μm, preferably 2 to 6 μm. If the dry thickness of the adhesive layer 6 is less than 0.1 μm, the adhesion between the printed label 2 and the container 7 may be insufficient. If the dry thickness of the adhesive layer 6 is greater than 10 μm, interlayer adhesion can be ensured, but manufacturing costs will increase unnecessarily.

[0095] <Container 7> The container 7 of the printed label container 1 of the present invention is preferably a metal can from the viewpoint of barrier properties, impact resistance, gloss, etc. The metal can used as container 7 may be either a seamless can or a welded can, but a seamless can is particularly preferred. Such a seamless can is manufactured by subjecting various surface-treated steel sheets such as tin-free steel (TFS), various plated steel sheets such as tin-plated steel, light metal sheets such as aluminum, inorganic surface-treated light metal sheets that have undergone chemical conversion treatment such as chromium phosphate, or resin-coated metal sheets in which a coating of a thermoplastic resin such as polyester resin is formed on these metal sheets, to conventionally known means such as drawing and redrawing, bending and stretching by drawing and redrawing (stretching), bending and stretching and ironing by drawing and redrawing, or drawing and ironing, or impact processing of light metal sheets.

[0096] <Glossiness G> Glossiness G (gloss value) is a numerical value that represents the degree of glossiness. The magnitude of glossiness G represents the degree of specular reflection when light is shone on the surface of the object being measured, and is defined by the ratio of the intensity of reflected light at the measurement point to the intensity of reflected light from a gloss standard plate.

[0097] The printed label container 1 of the present invention preferably has a glossiness G of 50 or higher at a reflection angle of 60°, obtained by measuring the outer surface of the printed label container 1, and is particularly preferably in the range of 70 to 95. If the glossiness G is less than 50, the design of the printed label container 1 is inferior. The glossiness G is usually measured with a gloss checker or the like.

[0098] <rsm ra> The printed label container 1 of the present invention preferably has a parameter RSm / Ra of 150 or more, and particularly preferably in the range of 150 to 200, which is expressed by the average length RSm obtained by measuring the outer surface of the printed label container 1 in accordance with the JIS-'01 standard and the arithmetic surface roughness Ra. If RSm / Ra is less than 150, the design of the printed label container 1 is inferior.

[0099] RSm is a horizontal parameter that represents the average length Xs of the contour curve elements. A large RSm means that the distance between peaks on the surface of the object being measured is long, indicating a low density of surface irregularities. On the other hand, Ra is a vertical parameter that represents the average absolute value of Z(x) at the reference length. A small Ra means that the surface irregularities are small.

[0100] To increase the gloss value, it is necessary to reduce the amount of diffuse reflection and increase the amount of specular reflection. A larger RSm / Ra ratio means that the numerator RSm is larger, indicating a lower density of surface irregularities, and the denominator Ra is smaller, indicating smaller surface irregularities. Therefore, an RSm / Ra value above a certain level indicates a large amount of specular reflection, resulting in a high gloss G (gloss value) and superior gloss.

[0101] <Method for manufacturing container 1 with printed label> The present invention provides a method for manufacturing a printed label container 1, which includes a manufacturing method (1) in which a front printing layer 4a and a back printing layer 4b are formed as the printing layer 4, and manufacturing methods (2) and (3) in which only the back printing layer 4b is formed as the printing layer 4.

[0102] <Method of manufacturing container 1 with printed label (1)> The present invention provides a method for manufacturing a printed label container 1 (1) that includes at least the steps of: forming a surface printing layer 4a on one side of a base film 3; forming a varnish layer 5 on the surface printing layer 4a; forming a back printing layer 4b on the other side of the base film; forming an adhesive layer 6 on the back printing layer 4b; a preheating step of partially curing the varnish layer 5 to produce a printed label 2; and a laminating step of attaching the printed label 2 to the outer surface of a container 7. The method provides a method for manufacturing a printed label container 1 having the configuration shown in Figure 1 of the present invention.

[0103] Furthermore, the manufacturing method (1) for the container 1 with a printed label uses a printing press having n printing units to form a surface printing layer 4a on the base film 3 with the 1st to (m-1)th printing units, then form a varnish layer 5 on the surface printing layer 4a with the mth printing unit, then use an inversion machine to invert the base film 3 on which the surface printing layer 4a and varnish layer 5 have been formed, and form a back printing layer 4b on the back surface of the base film 3 opposite to the side on which the surface printing layer 4a and varnish layer 5 have been formed with the (m+1)th to nth printing units, and then form an adhesive layer 6 on the back printing layer 4b, wherein the number m, which is the number of the printing unit that forms the varnish layer 5, is preferably an integer from 2 to (n-1).

[0104] Furthermore, depending on the design of the printed layer 4, the thickness of the printed layer 4 may vary from place to place, resulting in uneven thickness. When the printed label 2 is wound up, if there is an uneven thickness, the winding pressure will be stronger only in the parts of the printed layer 4 that are thicker (parts where multiple color layers overlap), which may make blocking more likely. Therefore, to prevent unevenness, a thickness-adjusting varnish layer can be formed in the parts of the printed layer 4 that are thinner. For this reason, multiple printing units for forming the varnish layer may be provided, such as printing unit m1, printing unit m2, etc.

[0105] (Step of forming the surface printed layer 4a) First, printing is performed on one side of the base film 3 to form a surface printing layer 4a. Known printing methods include gravure printing, inkjet printing, and electrophotographic printing. Among these, gravure printing is preferred from the viewpoint of manufacturing efficiency.

[0106] After printing, the surface is heated and dried to form the surface printed layer 4a. Depending on the type of ink used, drying methods include ovens, dryers, ultraviolet curing, or electron beam curing. The heating temperature for heating and drying the surface printed layer 4a is preferably 60 to 150°C, and more preferably 60 to 100°C. If the drying temperature is below 60°C, drying will be insufficient, and there is a risk that it will mix with the varnish composition that will be applied later on top of the surface printed layer 4a. On the other hand, if it is higher than 150°C, there is a risk of over-curing. The heating time is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0107] The specific process involves passing the wound base film 3 through a printing press having n printing units. Preferably, the number of printing units n is in the range of 3 or more. The printing press is equipped with printing press ovens numbered 1 to n, corresponding to the 1st to nth printing units. Using the printing press, a surface printing layer 4a is formed on the base film 3 by the 1st to (m-1)th printing units. m is an integer between 2 and (n-1). That is, after each printing process by each printing unit, the film is partially dried in the printing press oven. The printing process is carried out using the ink filled in each printing unit, and after the printing process, the ink is dried in the printing press oven, forming the surface printing layer 4a.

[0108] (Step to form varnish layer 5) Next, varnish composition (i) or varnish composition (ii) is applied over the surface printed layer 4a. Known methods for application include various spray coatings such as air spray, airless spray, or electrostatic spray, as well as dip coating, roll coater coating, gravure coater coating, and electrodeposition coating. Among these, gravure coater coating is preferred because it allows for uniform and stable application of the coating film.

[0109] The coated varnish composition (i) or varnish composition (ii) is heated and dried to form a varnish layer 5. Drying methods include ovens and dryers. The heating temperature when heating and drying the varnish composition is preferably 80 to 150°C, and more preferably 100 to 130°C. If the drying temperature is below 80°C, the curing will be insufficient, and blocking may occur when the film is wound up. On the other hand, if the temperature is higher than 150°C, the varnish layer 5 may become over-cured, and the overlap suitability may decrease. The heating time when heating and drying the varnish composition is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0110] The specific process involves forming a varnish layer 5 on the surface printed layer 4a using the m-th printing unit. That is, as described above, the surface printed layer 4a is formed when the (m-1)-th printing unit performs the printing process and dries in the (m-1)-th printing machine oven. Then, the varnish composition (i) or varnish composition (ii) is applied on top of it using the m-th printing unit. Finally, it is heated and dried in the m-th printing machine oven to form the varnish layer 5. The number m, which is the number of the printing unit that forms the varnish layer 5, is an integer from 2 to (n-1).

[0111] (Process for forming the reverse side printing layer 4b) Next, printing is performed on the other side of the base film 3 to form a back-side printing layer 4b. Known printing methods include gravure printing, inkjet printing, and electrophotographic printing. Among these, gravure printing is preferred from the viewpoint of manufacturing efficiency.

[0112] After printing, the back surface is heated and dried to form the back-side printed layer 4b. Depending on the type of ink used, drying methods include oven, dryer, ultraviolet curing, or electron beam curing. The heating temperature for heating and drying the back-side printed layer 4b is preferably 60 to 150°C, and more preferably 60 to 100°C. If the drying temperature is below 60°C, drying will be insufficient, and there is a risk of mixing with the varnish composition that will be applied on top later. On the other hand, if it is above 150°C, there is a risk of over-curing. The heating time is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0113] The specific process involves, after the varnish layer 5 is formed, using a reversing machine to invert the base film 3 on which the surface printing layer 4a and varnish layer 5 are formed. Then, the (m+1)th to nth printing units print on the back side of the base film 3 opposite to the side on which the varnish layer 5 is formed. After each printing process, the (m+1)th to nth printing machine ovens dry the printed ink, forming the back printing layer 4b.

[0114] (Step of forming adhesive layer 6) An adhesive composition is applied to the back-side printed layer 4b after drying. The application method can be the same as the method described in the step for applying the varnish composition. Among these, a gravure coater is preferred because it allows for uniform and stable application of the coating film.

[0115] (Preheating process) The preheating step is a process for manufacturing the printed label 2 by partially curing the varnish layer 5 and the adhesive layer 6. The heating temperature in the preheating step is preferably 80 to 150°C, and more preferably 100 to 130°C. If the drying temperature is below 80°C, the curing will be insufficient, and blocking may occur when the film is wound up. On the other hand, if it is above 150°C, the varnish layer 5 and the adhesive layer 6 will become over-cured, and the overlap suitability may decrease. The heating time is preferably 1 to 20 seconds, and more preferably 1 to 12 seconds.

[0116] After the preheating process, the film is wound up to produce the printed label 2.

[0117] (Lamination process) The lamination process involves attaching the wound-up printed label 2 to the outer surface of the container 7. In the lamination process, the printed label 2 is pressed against the body of the container 7, which has been heated by high-frequency heating, with the edges overlapping so that the adhesive layer of the printed label 2 faces the body of the container 7. This process results in a container 1 with a printed label, in which the printed label 2 is laminated to the surface of the body of the container 7. A feature of the present invention is that, after the lamination process, the semi-cured varnish layer 5 and adhesive layer 6 can be fully cured without performing the conventional baking process.

[0118] In the lamination process, the heating temperature is preferably 160-190°C, and more preferably 170-180°C. If the heating temperature is below 160°C, the curing will be insufficient, and there is a risk that the film will not adhere properly due to poor adhesion. On the other hand, if the temperature is higher than 190°C, the risk of the film melting increases. Furthermore, the heating time is preferably 1-5 seconds, and more preferably 2-5 seconds.

[0119] In this way, a container 1 with a printed label having the configuration shown in Figure 1 is manufactured by manufacturing method (1).

[0120] <Manufacturing method for container 1 with printed label (2)> The present invention provides a method for manufacturing a printed label container 1 (2) that includes at least the steps of: forming a back-side printing layer 4b on one side of a base film 3; forming a varnish layer 5 on the other side of the base film 3; forming an adhesive layer 6 on the back-side printing layer 4b; a preheating step to partially cure the varnish layer 5 to produce a printed label 2; and a laminating step to attach the printed label 2 to the outer surface of a container 7. The method provides a printed label container 1 having the configuration shown in Figure 2 of the present invention.

[0121] Furthermore, in the manufacturing method (2) of the container 1 with a printed label, it is preferable to use a printing machine having n printing units to form a back-side printed layer 4b on the base film 3 with the 1st to (n-1)th printing units, then use an inversion machine to invert the base film 3 on which the back-side printed layer 4b has been formed, form a varnish layer 5 on the side of the base film 3 on which the back-side printed layer 4b has not been formed with the nth printing unit, invert the base film 3 on which the back-side printed layer 4b has been formed with an inversion machine, and then form an adhesive layer 6 on the back-side printed layer 4b.

[0122] (Process for forming the reverse side printing layer 4b) First, printing is performed on one side of the base film 3 to form a back-side printing layer 4b. Known printing methods include gravure printing, inkjet printing, or electrophotographic printing.

[0123] After printing, the back surface is heated and dried to form the back surface printing layer 4b. Depending on the type of ink used, drying methods include ovens, dryers, ultraviolet curing, or electron beam curing. The heating temperature for heating and drying the back surface printing layer 4b is preferably 60 to 150°C, and more preferably 60 to 100°C. If the drying temperature is below 60°C, drying will be insufficient, and there is a risk of mixing with the adhesive composition that will be applied on top later. On the other hand, if it is above 150°C, there is a risk of over-curing. The heating time is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0124] The specific process involves passing the wound base film 3 through a printing press having n printing units. The number of printing units n is preferably in the range of 3 or more. The printing press is equipped with printing press ovens numbered 1 to n, corresponding to the 1st to nth printing units. Using the printing press, the 1st to (n-1)th printing units form a back-side printing layer 4b on the base film 3. Furthermore, after each printing process by each printing unit, the film is partially dried in the printing press oven. That is, printing is performed using the ink filled in each printing unit, and after printing, the ink is dried in the printing press oven, forming the back-side printing layer 4b.

[0125] (Step to form varnish layer 5) Next, the other surface of the base film 3 is coated with varnish composition (i) or varnish composition (ii). The coating method is the same as that used in the manufacturing method (1) for the container with printed label 1. Among these, a gravure coater is preferred because it allows for uniform and stable coating.

[0126] The coated varnish composition (i) or varnish composition (ii) is heated and dried to form a varnish layer 5. Drying methods include ovens and dryers. The heating temperature when heating and drying the varnish composition is preferably 80 to 150°C, and more preferably 100 to 130°C. If the drying temperature is below 80°C, the curing will be insufficient, and blocking may occur when the film is wound up. On the other hand, if the temperature is higher than 150°C, the varnish layer 5 may become over-cured, and the overlap suitability may decrease. The heating time when heating and drying the varnish composition is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0127] The specific process involves inverting the base film 3, on which the backside printing layer 4b is formed, using a reversing machine. A varnish layer 5 is formed on the side of the base film 3 where the backside printing layer 4b is not formed, using the nth printing unit. That is, the nth printing unit applies either varnish composition (i) or varnish composition (ii). The varnish layer 5 is then heated and dried in the nth printing machine oven. A thickness-adjusting varnish layer can also be formed, and multiple printing units for forming the varnish layer may be provided.

[0128] (Step of forming adhesive layer 6) An adhesive composition is applied to the back surface printing layer 4b. The coating method is the same as that used in manufacturing method (1). Among these, a gravure coater is preferred because it allows for uniform and stable coating.

[0129] The specific process involves using a reversing machine to invert the base film 3 on which the varnish layer 5 has been formed, and then applying the adhesive composition onto the back surface printing layer 4b.

[0130] After this, the printed label 2 is produced by winding the film after a preheating process, similar to manufacturing method (1). Then, after a lamination process, similar to manufacturing method (1), the container 1 with the printed label, as shown in Figure 2, is produced by manufacturing method (2).

[0131] <Method of manufacturing container 1 with printed label (3)> The manufacturing method (3) of the present invention for a printed label container 1 is a manufacturing method in which the order of the steps for forming the varnish layer 5 and forming the back surface printing layer 4b is reversed in the manufacturing method (2), and is a method for manufacturing a printed label container 1 having the configuration shown in Figure 2 of the present invention.

[0132] Furthermore, the manufacturing method (3) for the container 1 with a printed label preferably involves using a printing machine having n printing units to form a varnish layer 5 on a base film 3 with the first printing unit, inverting the base film 3 on which the varnish layer 5 has been formed using an inversion machine, forming a backside printing layer 4b on the side where the varnish layer 5 has not been formed with the second to nth printing units, and then forming an adhesive layer 6 on the backside printing layer 4b.

[0133] (Step to form varnish layer 5) First, one side of the base film 3 is coated with either varnish composition (i) or varnish composition (ii). The coating method is the same as that used in the manufacturing methods (1) and (2) for the container with printed label 1. Among these, a gravure coater is preferred because it allows for uniform and stable coating.

[0134] The coated varnish composition (i) or varnish composition (ii) is heated and dried to form a varnish layer 5. Drying methods include ovens and dryers. The heating temperature when heating and drying the varnish composition is preferably 80 to 150°C, and more preferably 100 to 130°C. If the drying temperature is below 80°C, the curing will be insufficient, and blocking may occur when the film is wound up. On the other hand, if the temperature is higher than 150°C, the varnish layer 5 may become over-cured, and the overlap suitability may decrease. The heating time when heating and drying the varnish composition is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0135] The specific process involves passing the wound base film 3 through a printing press having n printing units. Preferably, the number of printing units n is in the range of 3 or more. The printing press is equipped with 1 to n printing press ovens corresponding to the 1st to nth printing units. Here, the 1st printing unit forms a varnish layer 5 on the base film 3. That is, the 1st printing unit coats the film with varnish composition (i) or varnish composition (ii). The film is then heated and dried in the 1st printing press oven to form the varnish layer 5. A thickness-adjusting varnish layer can also be formed, and multiple printing units may be provided for forming the varnish layer 5.

[0136] (Process for forming the reverse side printing layer 4b) Next, printing is performed on the other side of the base film 3 to form a back-side printing layer 4b. Known printing methods include gravure printing, inkjet printing, or electrophotographic printing.

[0137] After printing, the back surface is heated and dried to form the back surface printing layer 4b. Depending on the type of ink used, drying methods include oven, dryer, ultraviolet curing, or electron beam curing. The heating temperature for heating and drying the back surface printing layer 4b is preferably 60 to 150°C, and more preferably 60 to 100°C. If the drying temperature is below 60°C, drying will be insufficient, and there is a risk that it will mix with the adhesive composition that will be applied on top later. On the other hand, if it is above 150°C, there is a risk of excessive curing. The heating time is preferably 0.5 to 3 seconds, and more preferably 0.5 to 1 second.

[0138] The specific process involves, after the varnish layer 5 is formed, using a reversing machine to invert the base film 3 on which the varnish layer 5 is formed. Then, the second to nth printing units print on the back side of the base film 3 opposite to the side on which the varnish layer 5 is formed. After each printing process, the ink is dried by the second to nth printing machine ovens, and the back side printing layer 4b is formed.

[0139] (Step of forming adhesive layer 6) An adhesive composition is applied to the back-side printed layer 4b after drying. The application method can be the same as the method described in the step for applying the varnish composition. Among these, a gravure coater is preferred because it allows for uniform and stable application of the coating film.

[0140] The specific process involves coating the back-side printed layer 4b with an adhesive composition. Unlike manufacturing method (2), this method allows for coating the adhesive composition after the back-side printed layer 4b has formed without using a reversing machine, resulting in superior manufacturing efficiency.

[0141] After this, the printed label 2 is manufactured by winding the film after a preheating process, similar to manufacturing methods (1) and (2). Then, after a lamination process, similar to manufacturing methods (1) and (2), the container 1 with the printed label, as shown in Figure 2, is manufactured by manufacturing method (3).

[0142] <Other processes> The manufacturing method (1) to (3) for the container 1 with a printed label may include other steps other than those described above.

[0143] For example, a post-heating step may be added after the lamination process. Preferably, the varnish layer 5 is fully cured after the post-heating step. By including the post-heating step, the curing of the varnish layer 5 and the adhesive layer 6 is accelerated, resulting in a printed label container 1 with excellent scratch resistance and water resistance.

[0144] The heating temperature in the post-heating step is preferably 100 to 210°C, and more preferably 100 to 160°C. If the drying temperature is below 100°C, the curing will be insufficient, resulting in poor adhesion and the printed label 2 may not adhere properly to the container 7. On the other hand, if the temperature is higher than 210°C, the container 1 with the printed label and the printed label 2 itself may yellow. The heating time when heating and drying the varnish composition is preferably 20 to 120 seconds, and more preferably 20 to 60 seconds. In other words, the post-heating step in the present invention can be carried out at a lower temperature than the conventional baking process (approximately 190 to 210°C), and even with the post-heating step, it is more energy-efficient than the conventional baking process.

[0145] By undergoing this low-temperature post-heating process, the curing of the varnish layer 5 and the adhesive layer 6 is accelerated, resulting in a printed label container 1 with scratch resistance, water resistance, and film adhesion equivalent to that of conventional baked-on printed label containers. [Examples]

[0146] The present invention will be described in detail below with reference to experimental examples. However, the present invention is not limited to these examples.

[0147] <Varnish compositions, adhesive compositions, and inks> The following raw materials were weighed and mixed using an electronic balance in the following proportions, and then stirred for 1 minute at 3000 rpm at 25°C using a dispersion stirrer to prepare varnish compositions (i), (ii), and adhesive composition. The following gravure inks were also prepared. • Varnish composition (i) Polyester resin (A): Elitel UE-3210, manufactured by Unitika Ltd., 64 parts Polyester resin (B): Elitel UE-3600, manufactured by Unitika Ltd., 30.5 parts Block-type isocyanate (C): Duranate 17B-60P, manufactured by Asahi Kasei Corporation, 5 parts Silicone-modified acrylic resin (D): Cymac US-270, manufactured by Toagosei Co., Ltd., 0.5 parts • Varnish composition (ii) Epoxy resin (E): EPICLON7050, manufactured by DIC Corporation, 64 parts Epoxy resin (F): EPICLON HM-091, manufactured by DIC Corporation, 30 units Silicone-modified acrylic resin (G): Cymac US-270, manufactured by Toagosei Co., Ltd., 1 part Isophorone diisocyanate polymer (H): Desmodule 4470BA, manufactured by Sumika Covestro Urethane Co., Ltd., 5 parts • Adhesive composition Polyester resin (I): Elitel UE-3210, manufactured by Unitika Ltd., 34 parts Polyester resin (J): Elitel UE-3500, manufactured by Unitika Ltd., 8 parts Titanium dioxide (K): CR58-2, manufactured by Ishihara Sangyo Co., Ltd., 45 units Block-type IPDI (L): Desmodule BL2078 / 2, manufactured by Sumika Covestro Urethane Co., Ltd., 6 units Block-type HDI(M): Duranate 17B-60P, manufactured by Asahi Kasei Corporation, 4 parts Novolac-type epoxy resin (N): YDCN-700-7, manufactured by Nippon Steel Chemical & Material Co., Ltd., 3 parts. Gravure Ink LP Bio SX Series, manufactured by Toyo Ink Co., Ltd. VMCAN series, manufactured by Toyo Ink Co., Ltd.

[0148] <Method for manufacturing and evaluating containers with printed labels> (Experimental Examples 1-26) [Loving Evaluation] For Experimental Examples 1-10 (without post-heating step), a varnish composition was applied at a rate of 2.0 g / m² to the surface of a PET film (manufactured by Toyobo Co., Ltd., 12 μm thick). 2 The film was coated using a bar coater and dried at 80°C for 5 seconds. A gravure ink of any type was applied to the back of the film at a rate of 1.3 g / m². 2 The surface was coated using a bar coater and dried with a dryer at 80°C for 5 seconds. An adhesive composition was then applied at a rate of 4.0 g / m². 2 The labels were coated using a bar coater and dried with a dryer at 80°C for 5 seconds to produce printed labels. The adhesive composition coated surface of the printed labels was laminated to a metal can at the temperatures shown in Table 1 at a rate of 40 m / min to produce containers with printed labels as shown in Figure 2. For Experimental Examples 11-26 (with a post-heating step), a gravure printing press with 10 printing units was used to coat the surface of a PET film (manufactured by Toyobo Co., Ltd., 12 μm thick) with seven arbitrary spot color inks (printing units 1-7) using gravure printing. After each ink coating, the surface was dried at 60°C for 1 second. After ink coating, a varnish composition (printing units 8-9) was applied at a rate of 2 g / m². 2 The film was coated and dried at 100°C for 2 seconds. Using a reversing machine, silver ink (printing unit 10) was applied to the back of the PET film and dried at 80°C for 1 second. After drying, the adhesive composition was applied at a rate of 4 g / m². 2 Printed labels were prepared by coating with a coater and drying at 130°C for 10 seconds. The adhesive composition coated surface of the printed label was laminated to a metal can at the temperatures shown in Table 1 at a rate of 40 m / min, and then a post-heating process was performed in an oven at the temperatures shown in Table 1 for 65 seconds to produce a container with a printed label as shown in Figure 2. A cotton ball was wrapped around the tip of a 2-pound hammer, and 2cc of solvent (MEK:IPA=8:2) was evenly soaked into the cotton ball. A metal can with a printed label was cut open, and the solvent-soaked cotton ball was brought into contact with the surface of the varnish layer perpendicular to it. The hammer was then slid approximately 20cm wide to rub the coated surface. The number of back-and-forth strokes was measured when the varnish composition on the rubbed surface dissolved and 10% of the surface area was exposed. The number of back-and-forth strokes was measured three times, and the average number was calculated. The scores were divided into the following four levels. The results are shown in Table 1. (Loving rating score) ◎: 25 times or more ○: 20-24 times △: 15-19 times ×: 14 times or less

[0149] [Table 1]

[0150] (Experimental Examples 27-30, Reference Example 1) [Gross value measurement, Rsm / Ra measurement] The inks listed in Table 2 were applied to the front and back surfaces of a PET film (manufactured by Toyobo Co., Ltd., 12 μm thick) using a bar coater, and then dried at 80°C for 5 seconds. After ink application to each surface, a varnish composition was applied to the PET film surface at a rate of 2.0 g / m². 2 The film was coated using a bar coater and dried with a dryer at 80°C for 5 seconds. An adhesive composition was applied to the back surface of the PET film at a rate of 4.0 g / m². 2 The material was coated using a bar coater, dried with a dryer at 80°C for 5 seconds, and then printed to produce the labels. The adhesive composition coated surface of the printed label was laminated to a metal can at the temperatures shown in Table 2 at a rate of 40 m / min to produce a container with a printed label as shown in Figure 1 or Figure 2. Furthermore, as Reference Example 1, a metal can (conventional product) was prepared using a conventional varnish composition (DIC Graphics Co., Ltd., product name: 2WT202-01) and adhesive composition (DIC Graphics Co., Ltd., product name: 6LP117T), and manufactured in the same manner as conventional products, including a baking process (heating temperature: 190~210℃). The gloss level G of the outer surface of the body of the labeled container was measured using a gloss checker (Horiba, Ltd. Handy Gloss Meter IG-410) under the following conditions. The gloss levels were divided into three stages, with ○ or higher being considered acceptable. The results are shown in Table 2. (Glossiness rating: G) ◎: Gloss level G is equivalent to that of conventional products. ○: The gloss level G is slightly lower than that of conventional products, but still sufficient. ×: Gloss level G is significantly lower than that of conventional products. Furthermore, the outer surface of the body was measured using a surface roughness measuring instrument (manufactured by Tokyo Seimitsu Co., Ltd.) according to the measurement conditions described below. The parameter RSm / Ra, expressed by the average length RSm and the arithmetic surface roughness Ra, was also calculated. The scores were divided into the following four levels. The results are shown in Table 2. (Surface roughness measurement conditions) Measurement Standard: JIS '01 Standard Measurement Length: 10 mm Measurement Speed: 0.3 mm / s Preliminary Drive Length: Cutoff Wavelength / 3 × 2 Cutoff Wavelength: 0.8 mm (RSm / Ra Rating) ◎: RSm / Ra is at the same level as that of conventional products ○: RSm / Ra is slightly lower than that of conventional products ×: RSm / Ra is much lower than that of conventional products

[0151]

Table 2

[0152] (Experimental Examples 31 to 62) [Lamination Strength] A varnish composition was applied at 2.0 g / m 2 to the surface of a PET film (manufactured by Toyobo Co., Ltd., thickness: 12 μm) using a bar coater, and dried with a dryer at 80°C for 5 seconds. An arbitrary gravure ink was applied to the back surface of the film using a bar coater, and dried with a dryer at 80°C for 5 seconds. An adhesive composition was then applied at 4.0 g / m 2 thereto using a bar coater, and dried with a dryer at 80°C for 5 seconds to prepare a printed label. The adhesive composition-coated surface of the printed label was laminated onto a trimmed can at the temperature shown in Table 3, at 40 m / min and for the holding time shown in Table 3. When a post-heating step was performed, the post-heating step was carried out at the temperature shown in Table 3 for 65 seconds, to obtain a container with a printed label having the configuration shown in Figure 2. The obtained container was cut open into a flat plate, and cut into a 2 cm-wide strip such that the overlap portion and the single-wrap portion could be measured respectively. Lamination strength measurement was carried out using a tensile testing machine (Autocom universal testing machine, manufactured by TSE Co., Ltd.). Ratings were classified into the following four levels. The results are shown in Table 3. (Lamination Strength Rating) ◎: Material fracture at the overlap portion (tensile stress of 1 N or more) ○: Material failure in the overlapping section (tensile stress less than 1N) or material failure in the single overlapping section (tensile stress 2.5N or more) △: Material fracture at the single-lap section (tensile stress less than 2.5N) ×: Other than

[0153] [Table 3]

[0154] (Experimental Example 63) [Blocking properties] Using a gravure printing press with 10 printing units, seven arbitrary spot color inks (printing units 1 to 7) were applied to the surface of a PET film (manufactured by Toyobo Co., Ltd., 12 μm thick) by gravure printing, and each ink application was dried at 60°C for 1 second. After ink application, a varnish composition (printing units 8 to 9) was applied at a rate of 2 g / m². 2 The film was coated and dried at 100°C for 2 seconds. Using a reversing machine, silver ink (printing unit 10) was applied to the back of the PET film and dried at 80°C for 1 second. After drying, the adhesive composition was applied at a rate of 4 g / m². 2 The printed labels were produced by coating them with a coater and drying them at 130°C for 10 seconds. 3000m of printed labels were rolled up and left under conditions of 25°C and 50%RH. For 1 to 4 months, 3000m of the rolled film was rewinded, and the presence or absence of blocking was visually checked. The results are shown in Table 4. (Blocking rating) ○: No blocking occurred ×: Blocking occurred.

[0155] [Table 4]

[0156] (Experimental Examples 64-80) [Adhesion after neck and flange processing] Printed labels were prepared using the same procedure as in Experimental Example 63. The adhesive composition coated surface of the printed label was laminated to a metal can at the temperature shown in Table 5 at a rate of 40 m / min. If a post-heating step was performed, after lamination, a post-heating step was carried out in an oven at the temperature shown in Table 5 for 65 seconds to obtain a container with a printed label as shown in Figure 1. The resulting containers were subjected to neck and flange processing, and a visual evaluation was conducted. The visual evaluation involved visually checking the extent of lifting of the printed labels on the neck and body (straight section) in both the overlapping and single-lap sections. The evaluation was divided into the following four levels. The results are shown in Table 5. (Adhesion rating after neck and flange processing) ◎: The entire surface is laminated smoothly, with no lifting or bulging. ○: A state in which the area of ​​the non-uniform part is less than 5% of the total area. △: A state where the area of ​​the uneven portion is 5% or more but less than 20% of the total area. ×: A state where the area of ​​the uneven portion is 20% or more of the whole.

[0157] [Table 5]

[0158] (Experimental Examples 81-100) [Retort whitening test] Using the inks shown in Table 6, the adhesive composition coated surface of the printed label was laminated to a metal can at the temperatures shown in Table 6. Except for performing the post-heating step at the temperatures shown in Table 6 if necessary, a container with a printed label, as shown in Figure 1, was fabricated using the same procedure as in Experimental Examples 64-80. The resulting container with a printed label was then subjected to neck and flange processing. We prepared two samples of containers with printed labels after processing: one with 30 cans tightly packed together in a basket without being tied (untied), and another with three cans tied together and pressed (3-can tie). Three samples of the 3-can tie were prepared, labeled A, B, and C. Each sample was retorted at 130°C for 30 minutes, and the whitening state after processing was visually inspected. The scores were divided into the following four levels. The results are shown in Table 6. Note that for the untied samples, the number in parentheses to the right of the score indicates the number of cans that received that score. (Retort whitening rate score) ◎: No whitening observed ○: Although it is bleached, it is difficult to see in bright places with a light source, but the bleaching can be seen upon close inspection in dark places without a light source. △: The area is bleached, and this is easily noticeable in bright light. ×: Whitening is immediately noticeable.

[0159] [Table 6] [Industrial applicability]

[0160] The printed label containers of the present invention exhibit excellent scratch resistance, water resistance, and film adhesion without the need for heating through baking, and can therefore be widely used in a wide range of applications, such as beverage cans for soft drinks, coffee, tea, beer, carbonated drinks, food cans, aerosol cans, and tube cans. [Explanation of symbols]

[0161] 1. Container with printed label 2 Printed labels 3. Base film 4 printing layer 5 layers of varnish 6 Adhesive layer 7 Container< / rsm>

Claims

1. A container with a printed label, wherein the printed label comprises at least a base film, a printing layer, and an adhesive layer, and the printed label is attached via the adhesive layer, characterized in that a varnish layer is formed on the outermost surface of the base film opposite to the container.

2. The container with a printed label according to claim 1, wherein the printed layer is a surface printed layer located between the varnish layer and the base film.

3. The container with a printed label according to claim 1, wherein a back-side printing layer is formed between the base film and the adhesive layer.

4. The container with a printed label according to claim 3, wherein the back surface printing layer contains an inorganic pigment with a particle size of 0.05 μm to 200 μm.

5. The container with a printed label according to claim 4, wherein the inorganic pigment is a silver pigment, a white pigment, or a pearl pigment.

6. The varnish layer is formed from varnish composition (i) or varnish composition (ii), The varnish composition (i) contains 50 to 80 parts by mass of polyester resin (A) having a number average molecular weight of 8,000 or more and less than 30,000 and a glass transition temperature of 40°C or more and less than 65°C, 10 to 40 parts by mass of polyester resin (B) having a number average molecular weight of 10,000 or more and less than 35,000 and a glass transition temperature of 50°C or more and less than 80°C, 1 to 10 parts by mass of block-type isocyanate (C) having a dissociation temperature of 110 to 150°C, and 0.1 to 1.0 parts by mass of silicon-modified acrylic resin (D). The container with a printed label according to claim 1, wherein the varnish composition (ii) contains 50 to 90 parts by mass of epoxy resin (E) having an epoxy equivalent of 1500 or more and less than 2500, 10 to 40 parts by mass of epoxy resin (F) having an epoxy equivalent of 2500 or more and less than 3500, 0.5 to 3.0 parts by mass of silicone-modified acrylic resin (G), and 1.0 to 10 parts by mass of isophorone diisocyanate polymer (H).

7. The container with a printed label according to claim 1, wherein the adhesive composition forming the adhesive layer contains 10 to 40 parts by mass of polyester resin (I) having a number average molecular weight of 8,000 or more and less than 30,000 and a glass transition temperature of 40°C or more and less than 65°C, 1 to 10 parts by mass of polyester resin (J) having a number average molecular weight of 15,000 or more and less than 50,000 and a glass transition temperature of 5°C or more and less than 30°C, 40 to 60 parts by mass of titanium dioxide (K), 1 to 10 parts by mass of blocked isophorone diisocyanate (L), 1 to 10 parts by mass of blocked hexamethylene diisocyanate (M), and 1 to 5 parts by mass of novolac-type epoxy resin (N).

8. The container with a printed label according to claim 6, wherein the varnish composition (i) contains a hexamethylene diisocyanate polymer (O).

9. The container with a printed label according to claim 6, wherein the varnish composition (i) or the varnish composition (ii) contains nylon resin beads (P) having an average particle size of 5 to 20 μm.

10. The glossiness G obtained by measuring the outer surface of the labeled container at a reflection angle of 60° is 50 or more. The printed label container according to claim 1, wherein the parameter RSm / Ra, which is expressed by the average length RSm obtained by measuring the outer surface of the labeled container in accordance with the JIS-'01 standard and the arithmetic surface roughness Ra, is 150 or more.

11. The container with a printed label according to claim 1, wherein the varnish layer is in a fully cured state.

12. A seamless can with a printed label, as described in claim 1.

13. A method for manufacturing a container with a printed label, comprising the steps of: forming a surface printing layer on one side of a base film; forming a varnish layer on the surface printing layer; forming a back printing layer on the other side of the base film; forming an adhesive layer on the back printing layer; a preheating step of partially curing the varnish layer to manufacture a printed label; and a lamination step of attaching the printed label to the outer surface of the container.

14. Using a printing press having n printing units, a surface printing layer is formed on the base film by the 1st to (m-1)th printing units, a varnish layer is formed on the surface printing layer by the mth printing unit, then the base film with the surface printing layer and varnish layer is inverted using an inversion machine, a back printing layer is formed on the back surface of the base film opposite to the side with the surface printing layer and varnish layer formed by the (m+1)th to nth printing units, and then an adhesive layer is formed on the back printing layer. The method for manufacturing a container with a printed label according to claim 13, wherein m, which is the number of the printing unit that forms the varnish layer, is an integer from 2 to (n-1).

15. A method for manufacturing a container with a printed label, comprising the steps of: forming a back-printing layer on one side of a base film; forming a varnish layer on the other side of the base film; forming an adhesive layer on the back-printing layer; a preheating step of partially curing the varnish layer to manufacture a printed label; and a laminating step of attaching the printed label to the outer surface of the container.

16. A method for manufacturing a container with a printed label according to claim 15, comprising: using a printing press having n printing units, forming a back-side printing layer on a base film with the 1st to (n-1)th printing units; inverting the base film on which the back-side printing layer has been formed using an inverting machine; forming a varnish layer on the side of the base film where the back-side printing layer has not been formed using the nth printing unit; inverting the base film on which the back-side printing layer has been formed using an inverting machine; and then forming an adhesive layer on the back-side printing layer.

17. A method for manufacturing a container with a printed label according to claim 15, comprising: using a printing press having n printing units, forming a varnish layer on a base film with the first printing unit; using an inversion machine, inverting the base film on which the varnish layer has been formed; forming a backside printing layer on the side where the varnish layer has not been formed with the second to nth printing units; and then forming an adhesive layer on the backside printing layer.

18. A method for manufacturing a container with a printed label according to claim 13 or 15, further comprising a heating step after the laminating step, wherein the varnish layer after the heating step is fully cured.

19. The method for manufacturing a container with a printed label according to claim 13 or 15, wherein the varnish layer or adhesive layer is formed by gravure printing.

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