Label and method for manufacturing label

Abstract

This label has a base material layer, a first printing layer provided on the base material layer, and a second printing layer provided on the first printing layer. The first printing layer includes a plurality of solid lubricants. At least a part of the plurality of solid lubricants is exposed from a surface of the second printing layer. The surface of the second printing layer has an area ratio of an exposed region where the solid lubricants are exposed to the surface of the second printing layer in a top view of 3%-30% inclusive, based on the area of the surface in a top view.

Description

Label and label manufacturing method

[0001] The present disclosure relates to labels and methods for making same.

[0002] A label is a container packaging material used to package a container (e.g., a PET bottle, etc.) The label not only protects the container and makes it less slippery when held, but also provides various indications to the container.

[0003] In recent years, there has been an increase in the use of inkjet printing of machine-readable two-dimensional codes on the back of labels. The two-dimensional codes contain a URL that shows campaign entry conditions and information on whether or not the applicant has won.

[0004] Patent Document 1 discloses a packaging film characterized in that a non-shrinkable label on which a two-dimensional code is formed is attached to a shrinkable film.

[0005] Patent document 2 discloses a cylindrical label in which an arbitrary display such as lottery information is printed on the inner surface of a cylindrical film that has been specifically printed using a variable printable non-impact printer, and the arbitrary display is configured so as not to be visible from the outer surface of the cylindrical film.

[0006] JP 2017-032847 A JP 2001-228801 A

[0007] As in Patent Documents 1 and 2, a two-dimensional code or the like containing product information is printed on the inner surface of a label using an inkjet printer. The inkjet ink printed on the inner surface of the label hardens in a raised state of several microns. Therefore, when the manufactured labels are wound into a roll, blocking between the labels can occur.

[0008] Therefore, the present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a label that exhibits excellent blocking resistance and in which the occurrence of blocking due to winding of the label is suppressed.

[0009] The present invention provides the following label and label manufacturing method: (1) The label of the present invention is a label having a base layer, a first printed layer provided on the base layer, and a second printed layer provided on the first printed layer, wherein the first printed layer contains a plurality of solid lubricants, at least some of which are exposed from the surface of the second printed layer, and the ratio of the area of ​​the surface of the second printed layer viewed from above, in which the exposed region where the solid lubricant is exposed, is 3% or more and 30% or less, based on the area viewed from above.

[0010] (2) The label of the present invention is the label described in (1), in which the first printed layer is a single layer or multiple layers.

[0011] (3) The label of the present invention is a label according to (1) or (2), in which the average particle size of the solid lubricant is 2.0 μm or more and 12 μm or less.

[0012] (4) The label of the present invention is a label according to (1) or (2), in which the thickness of the second printed layer is 0.1 μm or more and 6.0 μm or less.

[0013] (5) The label of the present invention is a label described in (1) or (2), in which the solid lubricant includes at least one selected from the group consisting of polyethylene-based lubricants, polypropylene-based lubricants, polyester-based lubricants, and fluorine-based lubricants.

[0014] (6) The label of the present invention is a label according to (1) or (2), in which the first printed layer is a multi-layered layer.

[0015] (7) The label of the present invention is a label described in (1) or (2), in which the second printed layer is an inkjet printed layer partially provided on the first printed layer.

[0016] (8) The label manufacturing method of the present invention is a label manufacturing method including a plate printing process in which a first printing layer is formed on a base layer by plate printing, and a plateless printing process in which a second printing layer is formed on the first printing layer by plateless printing, wherein the label has a base layer, a first printing layer formed on the base layer, and a second printing layer formed on the first printing layer, and the first printing layer contains a plurality of solid lubricants, and at least a portion of the plurality of solid lubricants are exposed from the surface of the second printing layer.

[0017] The label of the present invention provides a label that exhibits excellent blocking resistance.

[0018] Fig. 1 is a schematic diagram of a film having a shrink label wound into a roll. Fig. 2 is a schematic cross-sectional view of a label in a first embodiment. Fig. 3 is a top view of the label shown in Fig. 2 viewed from the top (second printed layer side). Fig. 4 is a schematic cross-sectional view of a label in a second embodiment. Fig. 5 is a schematic cross-sectional view of a label in a fourth embodiment. Fig. 6 is an enlarged image of the label of Example 1 viewed from the top.

[0019] The label of the present invention is a label having a base layer, a first printed layer provided on the base layer, and a second printed layer provided on the first printed layer, wherein the first printed layer contains a plurality of solid lubricants, at least some of which are exposed from the surface of the second printed layer, and the surface of the second printed layer has an area, viewed from above, of which the ratio of the area of ​​the exposed region where the solid lubricants are exposed (hereinafter also referred to as the "lubricant exposure ratio R") is 3% or more and 30% or less, based on the area viewed from above.

[0020] The label of the present invention is not limited in its application method as long as it is a label that is used by application, and examples thereof include shrink labels, wrap-around labels, stretch labels, tack labels, in-mold labels, and glue labels. In this embodiment, a "shrink label" refers to a label that shrinks when heated at 70°C to 120°C, and is also called a heat-shrinkable label. Shrink labels can shrink to fit the shape of a container. In this embodiment, a "wrap-around label" refers to a label that is wrapped around and applied, and is also called a roll label.

[0021] When a label is shrunk before being attached to a container, the lubricant exposure ratio R changes before and after shrinkage. In a label that is shrunk before being attached, the above-mentioned lubricant exposure ratio R is the measured value before shrinkage. For example, when the label according to the present invention is a shrink label, the measured value is the value before heat shrinkage.

[0022] As for parameters other than the lubricant exposure ratio R described below, there are parameters that change before and after shrinkage in a label that is attached in a shrunk state, similar to the lubricant exposure ratio R. Unless otherwise specified, parameters that change before and after shrinkage are measured values ​​in the state before shrinkage.

[0023] The label of the present invention, with a lubricant exposure ratio R that satisfies the above-mentioned range, suppresses the occurrence of blocking and exhibits excellent blocking resistance. This is because, even when the labels of the present invention are stacked, the contact area between the labels is reduced because the solid lubricant is exposed from the printed surface of the label. Because the label of the present invention reduces the contact area between the labels, friction at the contact surface is also reduced, inevitably improving friction resistance. Furthermore, the label of the present invention also reduces the slipperiness at the contact surface between the conveying roll, mandrel, etc. and the labeler jig in a labeler (label application machine), inevitably improving application ease.

[0024] FIG. 1 illustrates an example of a situation in which blocking occurs. FIG. 1 is a schematic diagram of a film having a shrink label wound into a roll. A shrink label 120 is formed by successively printing various colors, layers, etc. on the film in a printing press, and the film is wound into a roll. FIG. 1 illustrates a film on which two rows of the shrink label 120 are printed. After printing and winding into a roll, the shrink label 120 becomes thicker in the roll 110 where the printed layers overlap. As illustrated in FIG. 1 , winding the shrink label 120 into a roll causes overlapping printed layers, such as the second printed layer portion described below, to overlap, thickening the region 111 of the roll 110 and increasing the winding pressure. Blocking refers to the phenomenon in which, when the film is unwound from the roll 110, the printed layer of the shrink label 120 and the shrink label base layer adhere to each other, making them less likely to separate, for example, in the region 111. Peeling off the difficult-to-peel portion can result in the problem of peeling off the printed layer of the shrink label 120. Although not shown, the unprinted portion is recessed compared to the portion with high winding pressure.

[0025] The wound roll 110 is stored, for example, for several hours to several days, after which the film is unwound from the roll 110, slit along the boundary line 121 printed on the two lines, and each separated film is wound onto its own roll. Blocking can also occur in this roll, as described above. The film is then unwound from each roll, processed into a tubular bag using a bag-making machine, folded flat, and wound again into a roll. The tubular shrink labels can be used as shrink labels by cutting between the labels. The tubular shrink labels can be used as labels to be attached to containers in beverage factories, food factories, and the like. Note that while the above description uses a film having a shrink label 120 as an example, blocking can also occur in films having roll labels (wrap-on labels).

[0026] Hereinafter, embodiments of the present invention will be described. However, the embodiments of the present invention are not limited thereto. In this specification, the notation in the form of "A to Z" means the upper and lower limits of a range (i.e., from A to Z), and when no unit is specified for A and only a unit is specified for Z, the unit of A and the unit of Z are the same.

[0027] [First Embodiment] FIG. 2 is a schematic cross-sectional view showing a label according to a first embodiment. As shown in FIG. 2, the label 1 includes a base layer 10, a first printed layer 11, and a second printed layer 12, which are provided in this order. The first printed layer 11 may be provided on the entire surface or a portion of the surface of the base layer 10. The second printed layer 12 is preferably provided on a portion of the surface of the first printed layer 11. The label according to the first embodiment is not limited to any particular label, as long as it has the layer structure of "second printed layer / first printed layer / base layer" described above. For example, the label may have a layer structure of "second printed layer / first printed layer / base layer / first printed layer / second printed layer." In this embodiment, the second printed layer 12 side may be referred to as the upper surface, and the base layer 10 side may be referred to as the lower surface. The first printed layer 11 includes a plurality of solid lubricants 13. At least a portion of the solid lubricants 13 are exposed from the surface of the second printed layer 12. The plurality of solid lubricants 13 may include those that are not exposed from the surface of the second printed layer 12, or may include those that remain within the first printed layer 11 and do not reach the second printed layer 12. Furthermore, in the region of the first printed layer 11 where the second printed layer 12 is not provided, it is preferable that the first printed layer 11 includes solid lubricants 13 that are exposed from the surface of the first printed layer 11, or may include solid lubricants 13 that remain within the first printed layer 11. Furthermore, it is preferable that at least a portion of the solid lubricants 13 that are exposed from the surface of the first printed layer 11 protrude from the first printed layer 11. As with the second printed layer 12, the first printed layer 11 has solid lubricants 13 exposed from its surface, which improves the slipperiness and attachment properties both in the region where the second printed layer 12 is provided and in the region where the second printed layer 12 is not provided. In Figure 2, the height of the portion of the solid lubricant 13 that protrudes from the surface of the first printed layer 11 is indicated by arrow 13A, and the thickness of the second printed layer is indicated by arrow 12A.

[0028] Fig. 3 is a top view of the label shown in Fig. 2 viewed from the top surface (second printed layer side). The top surface shown in the top view in Fig. 3 is composed of an area α where the second printed layer 12 is visible and an area β where the solid lubricant 13 is visible. The lubricant exposure ratio R is defined as the ratio of the area of ​​the area β where the solid lubricant 13 is visible to the total area of ​​the area α where the second printed layer 12 is visible and the area β where the solid lubricant 13 is visible.

[0029] The lubricant exposure ratio R is 3% or more and 30% or less, more preferably 5% or more and 20% or less, and even more preferably 8% or more and 19% or less.

[0030] <Substrate Layer> As the substrate layer in this embodiment, a thermoplastic label substrate can be used. For example, a heat-shrinkable label substrate or a non-heat-shrinkable label substrate can be used. Examples include polyester films made of polyester resins such as polyethylene teretaphthalate resins and polylactic acid resins; polystyrene films made of polystyrene resins such as styrene-butadiene block copolymers; polyolefin films made of olefin resins such as polyethylene and polypropylene; and polyvinyl chloride films made of vinyl chloride resins. The heat-shrinkable label substrate preferably has a heat shrinkage rate of 30% or more, more preferably 40% or more, and even more preferably 50% or more, in at least one direction when immersed in 90°C hot water for 10 seconds. The non-heat-shrinkable label substrate preferably has a heat shrinkage rate of less than 5%, more preferably 3% or less, in both directions when immersed in 90°C hot water for 10 seconds.

[0031] The substrate layer may be a transparent substrate layer or an opaque substrate layer. In this embodiment, "transparent" refers to a state in which printing on the back side of a certain layer or a certain portion can be seen from the front side. The transparent substrate layer may be a colorless transparent substrate layer or a colored transparent substrate layer. In this embodiment, "opaque" refers to a state in which printing on the back side of a certain layer or a certain portion cannot be seen from the front side.

[0032] The thickness of the base layer in this embodiment is not particularly limited, but is, for example, 8 μm or more and 100 μm or less, or 10 μm or more and 80 μm or less.

[0033] <First Printing Layer> The first printing layer is a single layer or multiple layers. A multiple layer first printing layer means that the first printing layer is two or more layers. The first printing layer is preferably a multiple layer, and more preferably two to three layers, because it makes the second printing layer less visible when viewed from the substrate layer side and improves the shielding effect. The first printing layer can be formed, for example, by plate printing using an ink for the first printing layer. When the first printing layer is a single layer, it can be formed, for example, by plate printing the ink for the first printing layer onto the substrate layer. When the first printing layer is a multiple layer, it can be formed, for example, by first plate printing the ink for the first printing layer onto the substrate layer and drying it, and then plate printing the ink for the first printing layer on top of that. In this embodiment, "plate printing" refers to a printing method in which printing is performed using a plate. Examples of plate printing include relief printing (flexographic printing), intaglio printing (gravure printing), lithographic printing (offset printing), and stencil printing (screen printing). In this embodiment, the first printing layer is preferably provided on the base layer by relief printing or intaglio printing, and more preferably provided on the base layer by intaglio printing (hereinafter also referred to as gravure printing).

[0034] The ink for the first printing layer used when forming the ink for the first printing layer by plate printing can be an oil-based ink or an aqueous ink. Conventional inks can be used as the oil-based ink and aqueous ink for forming the first printing layer. For example, an oil-based ink may be a mixture of a colorant such as a pigment or dye, a binder resin, and an organic solvent, with additives. For aqueous ink, a colorant may be a mixture of a water-soluble or water-dispersible binder resin, additives, etc., with water. Examples of additives include anti-settling agents, dispersants, antifoaming agents, stabilizers, fillers, antioxidants, UV absorbers, antistatic agents, color separation inhibitors, fragrances, deodorizers, etc.

[0035] The binder resin forming the first printing layer can be a known resin, such as a thermoplastic resin. Examples of thermoplastic resins include urethane-based resins, vinyl chloride-vinyl acetate copolymer resins, polyamide-based resins, acrylic-based resins, ethylene-vinyl acetate copolymer resins, chlorinated olefin-based resins, alkyd-based resins, cellulose-based resins (such as soluble cellulose, cellulose acetate propionate, and cellulose acetate butyrate), vinyl acetate-based resins, vinyl chloride-based resins, rosin-based resins (such as rosin, hardened rosin, polymerized rosin, rosin ester, and rosin-modified maleic acid resin), ketone-based resins, polybutyral-based resins, cyclized rubber-based resins, chlorinated rubber-based resins, petroleum-based resins, olefin-based resins, polyester-based resins, and polylactic acid-based resins. Among these, acrylic-based resins, urethane-based resins, and cellulose-based resins are preferred. The above resins may be used alone or in combination of two or more.

[0036] The first printing layer may contain a colorant or may not contain a colorant. When the first printing layer contains a colorant, the first printing layer may be a white plate-type printing layer containing a white pigment, a binder resin, and a solid lubricant. When the first printing layer does not contain a colorant, the first printing layer may be a transparent plate-type printing layer containing a binder resin and a solid lubricant. Examples of the white pigment include titanium dioxide, calcium carbonate, and zinc oxide. The white pigment may be contained in the first printing layer in an amount of 30% by mass to 85% by mass.

[0037] When the first printed layer in this embodiment is a single layer, the thickness of the first printed layer may be 0.1 μm or more and 5 μm or less, 0.2 μm or more and 4 μm or less, or 0.3 μm or more and 3.5 μm or less. When the thickness of the first printed layer is in the above numerical range, the blocking resistance of the label in this embodiment is improved.

[0038] When the first printed layer in this embodiment is a multi-layered layer, the thickness of the first printed layer may be 0.1 μm or more and 6 μm or less, 0.2 μm or more and 5 μm or less, or 0.3 μm or more and 4 μm or less. When the thickness of the first printed layer is in the above numerical range, the blocking resistance of the label in this embodiment is improved, and the shielding effect of the first printed layer is further improved.

[0039] <Solid Lubricant> The solid lubricant has a height 13A based on the surface of the first printed layer. If the height 13A of the solid lubricant is greater than the thickness 12A of the second printed layer, the solid lubricant can be exposed from the surface of the second printed layer. Therefore, it is preferable that the solid lubricant has the property of repelling the second printed layer. As the solid lubricant, for example, a solid lubricant containing at least one selected from the group consisting of polyethylene-based lubricants such as polyethylene wax, oxidized polyethylene wax, and fluorine-modified polyethylene wax, polypropylene-based lubricants such as polypropylene wax, polyester-based lubricants such as polyethylene terephthalate wax, and fluorine-based lubricants such as polytetrafluoroethylene wax can be used. Among these, it is preferable that the solid lubricant contains a polyethylene-based lubricant or a polypropylene-based lubricant.

[0040] The first printing layer may contain the solid lubricant in an amount of 0.5% by mass to 20% by mass, 1% by mass to 15% by mass, or 3% by mass to 12% by mass. When the content of the solid lubricant in the ink for the first printing layer is within the above numerical range, blocking resistance is improved.

[0041] The solid lubricant may have an average particle size of 2.0 μm or more and 12 μm or less, 3.0 μm or more and 10 μm or less, or 5.0 μm or more and 9.0 μm or less. When the average particle size of the solid lubricant is within the above numerical range, it becomes easier to obtain a label in which at least a portion of the solid lubricant is exposed from the surface of the second printing layer.

[0042] The shape of the solid lubricant is not particularly limited as long as it does not impair the effects of the present invention. Examples of the shape of the solid lubricant include spherical and elliptical shapes.

[0043] When the first printed layer is a multi-layer structure, the plurality of solid lubricants may be contained in at least one layer of the multi-layer structure, may be contained only in the layer in contact with the base layer, may be contained only in the layer in contact with the second printed layer, or may be contained in any layer. When the first printed layer is a multi-layer structure, the plurality of solid lubricants are preferably contained only in the layer in contact with the base layer of the multi-layer structure, since this further improves the shielding effect of the first printed layer.

[0044] <Second Printing Layer> The second printing layer can be formed, for example, by plateless printing using ink for the second printing layer. In this embodiment, "plateless printing" refers to a printing method that does not use a plate. In this embodiment, plateless printing is preferably laser printing, toner printing, or inkjet printing (IJP printing), and more preferably inkjet printing. With plateless printing, characters, designs, barcodes, two-dimensional codes, and the like created using digital data created on a computer can be directly printed. Two-dimensional codes refer to matrix-type two-dimensional codes such as QR Code (registered trademark) and stack-type two-dimensional codes, and are machine-readable codes that represent text information, URLs for accessing websites, and the like. Since the second printing layer is provided to represent characters, two-dimensional codes, designs, and the like, or a combination thereof, it is preferably provided partially on the first printing layer, and more preferably an inkjet printing layer provided partially on the first printing layer.

[0045] The ink for the second printing layer may be a laser coloring ink containing a binder resin and a laser coloring agent, a toner containing a colorant and a binder resin, or an inkjet ink. The ink for the second printing layer used when forming the ink for the second printing layer by inkjet printing may be an aqueous inkjet ink or an ultraviolet-curable inkjet ink (UV-IJP printing). Conventional inks may be used as the ink for forming the second printing layer. The aqueous inkjet ink may be a mixture of a colorant with a water-soluble or water-dispersible binder resin, additives, etc. In this embodiment, the colorant contained in the aqueous inkjet ink is preferably a colored dye, from the viewpoint of reducing clogging of inkjet nozzles. The ultraviolet-curable inkjet ink may be a mixture of a colorant, a low-molecular-weight component such as a monomer or oligomer, a photopolymerization initiator, and additives.

[0046] The binder resin forming the second printed layer can be a known resin. For example, a thermoplastic resin can be used. Examples of thermoplastic resins include urethane-based resins, vinyl chloride-vinyl acetate copolymer resins, polyamide-based resins, acrylic-based resins, ethylene-vinyl acetate copolymer resins, chlorinated olefin-based resins, alkyd-based resins, cellulose-based resins (such as soluble cellulose, cellulose acetate propionate, and cellulose acetate butyrate), vinyl acetate-based resins, vinyl chloride-based resins, rosin-based resins (such as rosin, hardened rosin, polymerized rosin, rosin ester, and rosin-modified maleic acid resin), ketone-based resins, polybutyral-based resins, cyclized rubber-based resins, chlorinated rubber-based resins, petroleum-based resins, olefin-based resins, polyester-based resins, and polylactic acid-based resins. The binder resin forming the second printed layer may be the same resin component as the binder resin forming the first printed layer, or it may be a different resin component. When the second printing layer is formed from an ultraviolet-curable inkjet ink, the binder resin is preferably an acrylic resin formed by reaction and solidifying a monomer component or an oligomer component. Only one type of binder resin may be used, or two or more types may be used.

[0047] The second printed layer may contain a colorant or may not contain a colorant. When the second printed layer contains a colorant, the colorant is preferably a colorant other than a white pigment, and is preferably a black colorant such as carbon black or a navy blue colorant such as copper phthalocyanine blue. The second printed layer may contain the colorant in an amount of 1% by mass or more and 40% by mass or less.

[0048] The colorant may be in any form, such as a solid, liquid, or gel. When the colorant is solid, the average particle size of the colorant is preferably smaller than the average particle size of the solid lubricant contained in the ink for the first printing layer. This is because the solid lubricant is more likely to be exposed from the surface of the second printing layer. The average particle size of the colorant may be, for example, less than 2 μm or 1.5 μm or less.

[0049] The second printed layer may be made of ink containing a solid lubricant or ink not containing a solid lubricant. When the second printed layer is an inkjet printed layer, it is preferable that the second printed layer be made of ink not containing a solid lubricant, in order to prevent clogging of the nozzle for ejecting the ink for the second printed layer and to make it easier for the solid lubricant contained in the first printed layer to be exposed from the surface of the second printed layer.

[0050] The thickness of the second printed layer may be 0.1 μm or more and 6.0 μm or less, 0.15 μm or more and 5.0 μm or less, or 0.2 μm or more and 3.0 μm or less. The thickness 12A of the second printed layer is set to be smaller than the height 13A of at least some of the solid lubricants. By setting the thickness of the second printed layer within the above numerical range and the thickness 12A of the second printed layer to be smaller than the height 13A of multiple solid lubricants, it is possible to easily produce a label in which the solid lubricant is exposed from the surface of the second printed layer.

[0051] <Uses> In the label of the first embodiment, when the first printing layer is white and the second printing layer is a color such as black or navy blue, the second printing layer is preferably provided on a portion of the surface of the first printing layer, thereby allowing the second printing layer to express characters, designs, two-dimensional codes, etc. against the white background of the first printing layer. In this case, the white first printing layer is formed by plate printing. By providing the white color by plate printing, the white density can be increased, thereby improving the shielding properties of the first printing layer. Furthermore, the second printing layer is formed by plateless printing, allowing the colored second printing layer to be formed by plateless printing. By providing the color by plateless printing, the design can be changed for each label (the display formed by the second printing layer can be variable printed). Furthermore, when the label of the first embodiment is attached with the second printing layer facing the container, the display of the second printing layer cannot be seen when attached to the container due to the shielding effect of the first printing layer. However, after the label is removed, the display of the second printing layer can be seen from the second printing layer side.

[0052] In the label of the first embodiment, when the base layer is transparent, the first printed layer is transparent, and the second printed layer is a color such as black or navy blue, the second printed layer can be seen through the base layer and the first printed layer from the base layer side. In this configuration, the transparent first printed layer may be a translucent first printed layer, and the translucent first printed layer may be, for example, a white translucent first printed layer containing a white pigment.

[0053] In the label of the first embodiment, it is more preferable that the first printed layer is a multi-layered layer, and all of the multi-layered layers are white. When the first printed layer is a multi-layered layer, and all of the multi-layered layers are white, the white transmission density of the first printed layer is increased, thereby further improving the shielding effect of the first printed layer and making it more difficult to see the second printed layer when viewed from the base layer side.

[0054] Second Embodiment FIG. 4 is a schematic cross-sectional view illustrating a label according to a second embodiment. As shown in FIG. 4 , in the second embodiment, the label 2 includes a base layer 20, a design printing layer 24, a first printing layer 21, and a second printing layer 22, in this order. The label according to the second embodiment differs from the label according to the first embodiment in that it includes a design printing layer. The label according to the second embodiment is not limited to any label having the layer structure of "second printing layer / first printing layer / design printing layer / base layer" described above. In the label 2 shown in FIG. 4 , the first printing layer 21 is a single layer. Although not shown, the first printing layer 21 in the label 2 may be multi-layered. The design printing layer 24 may be partially or entirely printed on the base layer 20, and the first printing layer 21 is provided on the design printing layer 24 and on the base layer 20 where no design printing layer is provided. In the second embodiment, the components other than the design printing layer 24 are the same as those described above, and therefore will be omitted.

[0055] The label of this embodiment has a design printing layer 24, which provides it with an excellent appearance. The design printing layer 24 is formed using one or more inks containing different colorants. The design printing layer 24 can be formed using known printing inks and various printing methods such as gravure printing. The design printing layer 24 is a layer that displays a visible pattern, text, etc. The thickness of the design printing layer 24 can be, for example, 0.5 μm or more and 5 μm or less.

[0056] In the label of the present embodiment, the first printed layer may be a transparent layer or an opaque layer. The first printed layer is preferably an opaque layer, and more preferably a white opaque layer.

[0057] <Uses> In the label of the second embodiment, when the base layer is transparent and the first printing layer is white, the white first printing layer becomes the background color (white) of the design printing layer and the second printing layer. In other words, the first printing layer improves the visibility of each printing layer by shielding the colors of the design printing layer and the second printing layer. When the second printing layer of the label is attached so that it contacts the container, the second printing layer can be seen from the second printing layer side after the label is removed.

[0058] In the label of the second embodiment, when the substrate layer and the first printing layer are transparent, the design printing layer can be seen through the substrate from the substrate layer side. Also, in areas where the design printing layer is not provided, the second printing layer can be seen through the substrate and the first printing layer.

[0059] [Third Embodiment] The third embodiment differs from the label of the second embodiment only in the stacking position of the design printing layer, with the design printing layer 24, base layer 20, first printing layer 21, and second printing layer 22 being provided in this order. The label of the third embodiment is not limited as long as it has the layer structure of "second printing layer / first printing layer / base layer / design printing layer" described above. In the third embodiment, the components other than the stacking position of the design printing layer 24 are the same as those described above, and therefore will be omitted.

[0060] <Uses> In the label of the third embodiment, when the base layer is opaque, the color of the base layer becomes the background color of the design printing layer and the first printing layer, and the color of the first printing layer (or the color of the first printing layer mixed with the base layer) becomes the background color of the second printing layer. In other words, the base layer improves the visibility of each printing layer by shielding the colors of the design printing layer and the first printing layer. When the second printing layer of the label is attached so that it contacts the container, the second printing layer can be seen from the second printing layer side after the label is removed.

[0061] In the label of the third embodiment, when the base layer and the first printing layer are transparent, the second printing layer can be seen through the base layer and the first printing layer from the design printing layer side.

[0062] [Fourth Embodiment] FIG. 5 is a schematic cross-sectional view illustrating a label according to a fourth embodiment. As shown in FIG. 5, in the fourth embodiment, the label 3 includes a substrate layer 30, a silver ink layer 35, a first printed layer 31, and a second printed layer 32, in this order. The label according to the fourth embodiment differs from the label according to the first embodiment in that it includes a silver ink layer. The label according to the fourth embodiment is not limited to any label having the layer structure of "second printed layer / first printed layer / silver ink layer / substrate layer" described above. In the label 3 shown in FIG. 5, the first printed layer 31 is a single layer. Although not shown, the first printed layer 31 in the label 3 may be multi-layered. Although not shown, the label 3 may include a design printed layer between the substrate layer 30 and the silver ink layer 35, and the silver ink layer 35 may be partially or entirely printed on the design printed layer. In the fourth embodiment, components other than the silver ink layer 35 are the same as those described above, and therefore will be omitted.

[0063] The silver ink layer is provided on the label for the purpose of making the second printed layer difficult to see when viewed from the base layer side and shielding the second printed layer. The silver ink layer can be, for example, a layer containing an aluminum pigment and a binder resin. The aluminum pigment can be spherical aluminum particles, scaly (flake-like) aluminum pieces, thin-film aluminum pieces, or the like. The binder resin can be any of the binder resins described above.

[0064] The content of the aluminum pigment in the silver ink layer may be, for example, 10% by mass or more and 70% by mass or less.

[0065] The thickness of the silver ink layer may be 0.05 μm or more and 2 μm or less, since this allows for better shielding of the second printed layer.

[0066] [Method of Using the Label] The labels of the first to fourth embodiments can be used for metal containers, glass containers, plastic containers such as PET bottles, etc. The labels of the first to fourth embodiments can also be used to package daily necessities such as beverages, foods, seasonings, and detergents, as well as medicines and cosmetics.

[0067] [Label Manufacturing Method] This embodiment is one form for manufacturing the label of the first embodiment. This embodiment is a label manufacturing method including a plate printing step of providing a first printing layer on a base layer by plate printing, and a plateless printing step of providing a second printing layer on the first printing layer by plateless printing, wherein the label has a base layer, the first printing layer provided on the base layer, and a second printing layer provided on the first printing layer, the first printing layer containing a plurality of solid lubricants, at least some of which are exposed from the surface of the second printing layer.

[0068] <Plate Printing Step> In the plate printing step, first, an ink for the first printing layer is applied to one surface of the base layer. The ink for the first printing layer contains a solid lubricant. A known plate printing method can be used to apply the ink for the first printing layer. Among these, the plate printing step is preferably relief printing or intaglio printing, and more preferably intaglio printing (gravure printing). The applied ink for the first printing layer is then solidified by drying, curing, or the like to form the first printing layer.

[0069] <Plateless Printing Step> In the plateless printing step, the ink for the second printing layer is applied to the surface of the first printing layer formed on the base layer. A known plateless printing method can be used to apply the ink for the second printing layer. Among these, inkjet printing is preferred for the plateless printing step. The applied ink for the second printing layer is then solidified by drying, curing, or the like to form the second printing layer.

[0070] The present invention will be explained in more detail below with reference to examples and comparative examples, but the present invention is not limited to these examples. In the examples and comparative examples, the blending amounts expressed as "%" and "parts" are by mass % and parts by mass unless otherwise specified.

[0071] [Test Example 1] (1) Preparation of ink for first printing layer The following components were blended to prepare inks A, B, and C for the first printing layer. For ink D for the first printing layer, only white gravure ink (trade name: NT-Hilamic 701 White, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.) was used.

[0072] <Ink A for first printing layer> White gravure ink (trade name: NT-Hilamic 701 White, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.): 100 parts by mass Paraffin wax (trade name: SASOLWAX SPRAY105G, manufactured by SASOL): 1 part by mass

[0073] <Ink B for first printing layer> White gravure ink (trade name: NT-HILAMIC 701 White, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.): 100 parts by mass Paraffin wax (trade name: SASOLWAX SPRAY105G, manufactured by SASOL): 3 parts by mass

[0074] <Ink C for first printing layer> White gravure ink (trade name: NT-HILAMIC 701 White, manufactured by Dainichiseika Color & Chemicals Mfg. Co., Ltd.): 100 parts by mass Paraffin wax (trade name: SASOLWAX SPRAY105G, manufactured by SASOL): 5 parts by mass

[0075] <Method for measuring the average particle size of solid lubricant> The average particle size (median diameter D50) of the solid lubricant was measured using a particle size distribution measuring device (trade name: Microtrack 3300EX II, manufactured by Microtrack Bell Co., Ltd.) using a laser diffraction / scattering method. The average particle size of the solid lubricant was 7 μm.

[0076] (2) Label Production Example 1 First, a first printing layer was formed by plate printing on the base layer. The ink A for the first printing layer was applied in one coat by gravure printing using a small gravure printing machine and a gravure plate to one side of a 35 μm thick shrink film (product name: HST, manufactured by Gunze Co., Ltd.), and then dried and solidified to form a first printing layer with a thickness of 1.2 μm. For the gravure printing, the ink A for the first printing layer, which had been prepared to have a viscosity of 16 mPa s at a temperature of 20° C., was diluted and used. The gravure plate used was an engraved plate with a line count of 70 L / inch and an angle of 0°.

[0077] Next, a second printed layer was formed on the first printed layer by plateless printing. A second printed layer was formed on the first printed layer using an ultraviolet-curable UV-IJP ink and an IJP printer. The UV-IJP ink contained no wax and contained a black colorant. The second printed layer was formed to a thickness of 2 μm at a speed of 50 m / min with a 5 pL droplet. In this way, a shrink label was produced with a configuration of [substrate layer (thickness: 35 μm) / first printed layer (ink A, thickness: 1.2 μm) / second printed layer (thickness: 2 μm)].

[0078] Example 2 A shrink label having a structure of [substrate layer (35 μm) / first printed layer (ink B, thickness: 1.2 μm) / second printed layer (thickness: 2 μm)] was produced in the same manner as in Example 1, except that gravure printing was carried out using ink B for the first printed layer instead of ink A for the first printed layer.

[0079] Example 3 A shrink label having a structure of [substrate layer (35 μm) / first printed layer (ink C, thickness: 1.2 μm) / second printed layer (thickness: 2 μm)] was produced in the same manner as in Example 1, except that gravure printing was carried out using ink C for the first printed layer instead of ink A for the first printed layer.

[0080] Example 4 The shrink label produced in Example 2 was immersed in hot water at 90°C, and the shrink label was shrunk by 10% in the main shrinkage direction. This was the same as Example 2, except that the shrink label shrunk by 10% in the main shrinkage direction.

[0081] Example 5 A shrink label having a configuration of [base material layer (35 μm) / first printed layer (ink B and ink B, thickness: 2.0 μm) / second printed layer (thickness: 2 μm)] was produced in the same manner as in Example 1, except that the first printed layer was a layer obtained by applying ink B for the first printed layer to the base material layer in one coat by gravure printing, drying and solidifying, and then applying ink B for the first printed layer again in one coat by gravure printing, and drying and solidifying.

[0082] Example 6 A shrink label having a configuration of [base layer (35 μm) / first printed layer (ink B and ink D, thickness: 2.2 μm) / second printed layer (thickness: 2 μm)] was produced in the same manner as in Example 1, except that the first printed layer was a layer obtained by applying ink B for the first printed layer to the base layer in a single coat by gravure printing, drying and solidifying, and then applying ink D for the first printed layer in a single coat by gravure printing, and drying and solidifying.

[0083] Comparative Example 1 A shrink label having a structure of [substrate layer (35 μm) / first printed layer (ink D, thickness: 1.2 μm) / second printed layer (thickness: 2 μm)] was produced in the same manner as in Example 1, except that gravure printing was carried out using ink D for the first printed layer instead of ink A for the first printed layer.

[0084] (3) Evaluation The shrink labels obtained in the examples and comparative examples were evaluated as follows. The evaluation results are shown in Table 1.

[0085] <Measurement of Exposed Amount of Solid Lubricant> The top surfaces of the shrink labels obtained in the Examples and Comparative Examples were observed at 500x magnification using a microscope (product name: Digital Microscope VHX-7000, manufactured by Keyence Corporation), and photographed using a digital camera attached to the microscope. The photographed images were binarized using image analysis software "Image J." Threshold processing was performed using Otsu's binarization method. Figure 6 is an enlarged image of the label of Example 1 viewed from the top. The white area in Figure 6 corresponds to the second printed layer. The black area in Figure 6 corresponds to the solid lubricant exposed from the surface of the second printed layer. The areas of the second printed layer area and the solid lubricant area were calculated, and the lubricant exposure ratio R was calculated.

[0086] <Measurement of Label Blocking Property> Label pieces measuring 50 mm x 50 mm were randomly cut from the shrink labels obtained in the Examples and Comparative Examples. The labels were stacked so that the base layer of one label piece was in contact with the second printed layer of the other label piece. The stacked label pieces were subjected to a pressure of 0.2 MPa perpendicular to the contacting surfaces for 24 hours at a temperature of 40°C ± 2°C and a humidity of 80%. After that, one of the stacked label pieces, with the second printed layer in contact, was fixed, and the other label piece, with the base layer in contact, was peeled perpendicularly. The blocking property upon peeling was evaluated based on the feel and peeling sound according to the following criteria. In this test, the blocking property of the label is preferably good or usable, with good being more preferable. This test was not performed on Example 4, which was a sample after heat shrinkage. This is because the label is not wound up and collected after heat shrinkage, so blocking does not occur. Good (++): Label pieces do not stick together Usable (+): There is resistance or a peeling sound when peeling the label pieces together Poor (-): Label pieces are not completely stuck together or ink peeling is confirmed

[0087]

[0088] From the results in Table 1, the labels of Examples 1 to 3 had good results in terms of the exposed ratio of the solid lubricant and blocking properties. On the other hand, the label of Comparative Example 1 did not show good blocking properties. From the above results, it was found that the labels of the Examples had excellent blocking properties.

[0089] Test Example 2 A test was carried out to confirm how the exposed ratio of the solid lubricant changes due to thermal shrinkage using the labels of Examples 2 and 4. Table 2 shows the results.

[0090]

[0091] From the test example results in Table 2, it can be seen that the proportion of exposed solid lubricant was greater in Example 4 than in Example 2.

[0092] [Test Example 3] <Measurement of White Transmission Density> The white transmission density of the first printing layer in the labels of Examples 2, 5, and 6 was measured. Specifically, the labels were cut into random pieces of 50 mm x 50 mm, and the white transmission density of the first printing layer on which the second printing layer was not printed was measured at any three points using a black-and-white transmission densitometer (Ihac-T5 manufactured by Ihara Electronics Co., Ltd.), and the average of the measured values ​​was taken as the white transmission density. The results are shown in Table 3.

[0093]

[0094] From the test example results in Table 3, Examples 6, 5 and 2 had the highest white transmission density in this order.

[0095] The embodiments and examples disclosed herein are illustrative in all respects and should not be considered limiting. The scope of the present invention is defined by the claims, not by the embodiments and examples described above, and is intended to include all documents within the scope of the claims that have the same meaning as the claims and are within the scope of the claims.

[0096] 110 Roll, 120 Shrink label, 1, 2, 3 Label, 10, 20, 30 Base material layer, 11, 21, 31 First printed layer, 12, 22, 32 Second printed layer, 12A Thickness of second printed layer, 13, 23 Solid lubricant, 13A Height of solid lubricant, 24 Design printed layer, 35 Silver ink layer, α Region where second printed layer 12 is visible, β Region where solid lubricant 13 is visible.

Claims

1. A label having a base layer, a first printed layer provided on the base layer, and a second printed layer provided on the first printed layer, wherein the first printed layer contains a plurality of solid lubricants, at least some of which are exposed from the surface of the second printed layer, and the surface of the second printed layer has an area in which the solid lubricants are exposed, the ratio of the area of ​​the surface in which the solid lubricants are exposed, as viewed from above, to the area of ​​the surface in which the solid lubricants are exposed, as viewed from above, is 3% or more and 30% or less.

2. The label according to claim 1, wherein the first printed layer is a single layer or multiple layers.

3. A label according to claim 1 or 2, wherein the average particle size of the solid lubricant is 2.0 μm or more and 12 μm or less.

4. A label as described in claim 1 or 2, wherein the thickness of the second printing layer is 0.1 μm or more and 6.0 μm or less.

5. The label according to claim 1 or 2, wherein the solid lubricant comprises at least one selected from the group consisting of polyethylene-based lubricants, polypropylene-based lubricants, polyester-based lubricants, and fluorine-based lubricants.

6. The label according to claim 1 or 2, wherein the first printed layer is a multi-layer.

7. A label according to claim 1 or 2, wherein the second printing layer is an inkjet printing layer partially provided on the first printing layer.

8. A method for manufacturing a label, comprising: a plate printing step of providing a first printing layer on a base layer by plate printing; and a plateless printing step of providing a second printing layer on the first printing layer by plateless printing, wherein the label has a base layer, a first printing layer provided on the base layer, and a second printing layer provided on the first printing layer, the first printing layer containing a plurality of solid lubricants, and at least some of the plurality of solid lubricants being exposed from the surface of the second printing layer.

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