Tube container

Abstract

To provide a novel tube container, specifically a tube container that exhibits scratch resistance on the outer face of the container when coming into contact with an external object, which solves the current problem: during transportation of the tube container or the process of filling and sealing the tube container with contents, the trunk part of the tube container is sometimes damaged by tube-to-tube rubbing or rubbing with an external hard object such as a metal member, wherein the tube container of the present application exhibits scratch resistance at the trunk part, making it resistant to damage even in the above-described situation.SOLUTION: A tube container has a trunk part that is composed of a laminate in which at least a first substrate layer, a first sealant layer, a second substrate layer, and a second sealant layer are laminated in this order toward the inner side from the outer side; and furthermore, a protective layer is provided on the whole surface or at least a part of the outer side of the first substrate layer.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a tube container, and more particularly to a tube container having scratch resistance on the outer surface of the container when it comes into contact with an external object. [Background technology]

[0002] Conventional tube containers, particularly laminated tube containers, are made of polyolefins such as polyethylene, and the outer surface of the laminated tube containers is rarely printed. Printing is often done on the inner surface of the polyethylene terephthalate film that serves as the intermediate layer. See Patent Documents 1 and 2. The surface of the unprinted outer polyethylene layer is soft and is easily scratched when rubbed against an external hard object.

[0003] In a manufacturing line for packaging products of tube containers, where the contents are filled and sealed in tube containers, the tube containers must be transported at all stages, including when transporting empty tube containers, during the filling and packaging process, and after the completion of the filling and packaging process, and they come into contact with and are rubbed against guides on the transport conveyor. In addition, even in the filling and packaging equipment, the outer surface of the tube container may be damaged by contact with the jigs that hold the tube containers in place at each process within the equipment, or by contact with various handling devices during transportation between each process. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2005-144812 A [Patent Document 2] JP 2005-178851 A Summary of the Invention [Problem to be solved by the invention]

[0005] The present invention has been made in consideration of the above circumstances, and has an object to provide a tube container that improves the scratch resistance of the outer surface of the tube container, and that can maintain its aesthetic appeal without being scratched on the outer surface during the filling and packaging process of the tube container as described above. [Means for solving the problem]

[0006] The tube container of the present invention is a tube container consisting of a body portion having a pair of bonded ends and a shoulder portion, wherein the laminate of the body portion has at least a first base material layer, a second base material layer, and a second sealant layer laminated in this order from the outer surface to the inner surface, and further has a protective layer provided on the entire surface or at least a portion of the outer surface of the first base material layer.

[0007] By providing a protective layer on the outer surface of the cylindrical body of the tube container, scratch resistance is improved and the friction coefficient of the outer surface of the cylindrical body of the tube container is reduced. Effect of the Invention

[0008] According to the present invention, it is possible to provide a tube container that has improved scratch resistance on the outer surface thereof, and that is free from scratches during the filling and packaging process of the tube container, and that maintains its aesthetic appeal. Also, according to the present invention, the surface of the cylindrical body of the tube container has a low coefficient of friction, which prevents the tube container from getting caught or falling over on the filling and packaging line for packaged products of the tube container, and allows the filling and packaging line for packaged products of the tube container to operate stably, thereby contributing to a reduction in production costs. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a laminate of a cylindrical body portion of a tube container according to a first embodiment of the present invention. [Diagram 2] FIG. 4 is a cross-sectional view of a laminate of a cylindrical body portion of a tube container according to a second embodiment of the present invention. [Diagram 3]FIG. 11 is a cross-sectional view of a laminate of a cylindrical body portion of a tube container according to a third embodiment of the present invention. [Figure 4] FIG. 2 is an explanatory diagram of a member of a cylindrical body of a tube container. [Diagram 5] FIG. [Figure 6] FIG. 2 is a front view of a packaged product of a tube container containing a content. [Figure 7] This is the original roll for the cylindrical body of a tube container. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] The present invention will be described below with reference to the drawings, however, the present invention is not limited to the specifically exemplified embodiments or the various specifically described structures. In each drawing, the size and ratio of the components may be changed or exaggerated for ease of understanding, and parts that are unnecessary for the explanation or repeated reference numerals may be omitted for ease of viewing.

[0011] <First embodiment of the present invention> DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A tube container according to a first embodiment of the present invention will be described in detail below with reference to the drawings and the like.

[0012] First, a tube container 30 produced using the laminate 10 for the cylindrical body of a tube container according to the present invention will be described with reference to Figs.

[0013] The tube container 30 includes a cylindrical body 31 including the laminate 10 of the cylindrical body of the tube container, and a shoulder 35 and a mouth 36 that are produced by providing a synthetic resin to the cylindrical body 31 by a method such as compression molding or injection molding. A cap 37 is attached to the mouth 36 of the tube container 30.

[0014] The tube container 30 having the above-mentioned structure is obtained through the following manufacturing process.

[0015] First, as shown in Fig. 4, a pair of bonded ends (hereinafter, sometimes referred to as both ends) 33A, 33B of the laminate 10 of the cylindrical body of a tube container according to the present invention are overlapped, and the outer and inner surfaces of the overlapped parts are heat-sealed and bonded to form a body bonding part 32, thereby manufacturing a cylindrical body 31. Next, as shown in Fig. 5, the cylindrical body 31 is placed in a mold (not shown), and a shoulder part 35 and a mouth part 36 are formed at one opening (upper side) 34A of the cylindrical body 31 by a method such as compression molding or injection molding. In this way, the shoulder part 35 and the mouth part 36 are integrally molded at one opening (upper side) 34A of the cylindrical body 31, and the tube container 30 is manufactured. Then, a cap 37 is attached to the mouth part 36 of the tube container 30.

[0016] Next, an appropriate amount of contents 38, such as mustard paste, wasabi paste, or other contents, is filled into the tube container 30 from the other opening (lower side) 34B of the cylindrical body 31. Thereafter, the opening (lower side) 34B is welded to form a bottom seal part 39, and a packaged product 30A including the tube container 30 filled and packaged with the contents 38 is obtained.

[0017] Next, the laminate 10 for the cylindrical body of a tube container from which a tube container 30 is produced will be described with reference to Fig. 1. The laminate 10 for the cylindrical body of a tube container is a laminate having a first base material layer 11 and a first sealant layer 12, both of which have heat sealability, a second base material layer 13, and a second sealant layer 15, which are arranged in this order from the outer surface to the inner surface, as shown in Fig. 1. A protective layer 16 is provided on the surface of the first base layer 13 .

[0018] A protective layer 16 is formed on the outer surface of the first base material layer 11 using a coat layer by a coater or ink such as OP varnish, and an inner surface printed portion 13A including a desired pattern is formed on the inner surface of the second base material layer 13 using printing ink. The inner surface printed portion 13A may be provided on the outer surface of the second base material layer 13 using printing ink.

[0019] When a picture print is present on the inner surface of the protective layer 16, it is desirable that the protective layer 16 be constructed of a see-through layer so that the picture print can be seen from the outside.

[0020] The surface of the first base layer 11 on which the protective layer 16 is formed needs to have appropriate irregularities in order to ensure adhesion of the ink, etc. The first sealant layer 12 is often prepared in advance as a film, and the surface thereof is so smooth that when the ink, etc. is applied to the surface, the adhesion of the ink, etc. may be poor. In particular, when the film used for the first sealant layer 12 is formed by an inflation method, the surface tends to be easily smoothed.

[0021] In the case where the adhesion between the first sealant layer 12 and the protective layer 16 is poor as described above, a first base layer 11 can be bonded onto the first sealant layer 12 to provide the surface of the first base layer 11 with appropriate irregularities. The arithmetic mean height (Sa) of the surface of the first base layer 11 is preferably 0.1 to 1.0 μm. If it is less than 0.1 μm, there is a risk that the ink adhesion will be poor, and if it exceeds 1.0 μm, there is a risk that the ink will become mottled and the effect of protecting the surface will be poor. In addition, the material of the first base layer 11 is preferably low-density polyethylene in terms of cost and processability. When flexographic printing was performed on an LLDPE film with an arithmetic mean height (Sa) of 0.08 μm, the ink adhesion was poor and some of the print peeled off.

[0022] The first sealant layer 12 and the second base material layer 13 are joined by dry lamination, and the first base material layer 11 is formed by extrusion lamination on the surface of the first sealant layer 12. Furthermore, the second base material layer 13 and the second sealant layer 15 are joined by dry lamination.

[0023] In this specification, the terms "outer surface" and "inner surface" refer to the "outer surface" and "inner surface" when a tube container 30 is produced using the laminate 10 of the cylindrical body of the tube container. Additionally, the terms "upper side" and "lower side" refer to the mouth side and the opposite side of the mouth, respectively, when the tube container 30 is held with the mouth 36 and the cap 37 facing upward.

[0024] Next, the materials of each part constituting the laminate 10 of the cylindrical body of the tube container will be described.

[0025] The first substrate layer 11, the first sealant layer 12 and the second sealant layer 15 may include, for example, polyethylene (PE). Specifically, the first substrate layer 11, the first sealant layer 12 and the second sealant layer 15 may be made of the following materials:

[0026] The first base layer 11, the first sealant layer 12 and the second sealant layer 15 may be any material that can be melted and fused to one another by heat, and may be made of one or more of the following resins: low-density polyethylene (LDPE), medium-density polyethylene (MDPE), high-density polyethylene (HDPE), linear low-density polyethylene (LLDPE), polypropylene (PP), ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-propylene copolymer, methylpentene polymer, acid-modified polyolefin resins such as polyethylene or polypropylene modified with unsaturated carboxylic acids such as acrylic acid, methacrylic acid, maleic acid, maleic anhydride, fumaric acid, itaconic acid, and the like; polyvinyl acetate resins; polyester resins; polystyrene resins; and the like.

[0027] A polyethylene terephthalate (hereinafter, abbreviated as PET) layer can be used as the second base layer 13, and an inner surface printed portion 13A made of printing ink can be provided on the PET layer 13 by printing on the PET layer 13. The second base layer 13 also maintains the rigidity of the tube container.

[0028] In addition, instead of using a PET layer as the second base layer 13, a nylon layer may be used, or a PET layer having a metal vapor deposition film on at least one side and gas barrier properties may be used, or a nylon layer having a metal vapor deposition film on at least one side and gas barrier properties may be used.

[0029] Also, a PET layer having a vapor-deposited silica film on at least one surface thereof and thus having gas barrier properties may be used, or a nylon layer having a vapor-deposited silica film on at least one surface thereof and thus having gas barrier properties may be used.

[0030] Also, a PET layer having an aluminum oxide vapor deposition film on at least one surface thereof and thus having gas barrier properties may be used, or a nylon layer having an aluminum oxide vapor deposition film on at least one surface thereof and thus having gas barrier properties may be used.

[0031] When a nylon layer is used, it often has superior mechanical strength to a PET layer. Moreover, films provided with various vapor-deposited films have better gas barrier properties than substrate films.

[0032] Next, the protective layer 16 provided on the outer surface of the first base material layer 11 having heat sealability, and the inner surface printed portion 13A provided on the inner surface of the second base material layer 13 will be described.

[0033] 7, the protective layer 16 is provided in an area of ​​the laminate 10 of the cylindrical body of the tube container other than the pair of bonded ends 33A, 33B. The reason for providing the protective layer 16 in an area other than the pair of bonded ends 33A, 33B is that the pair of bonded ends 33A, 33B are portions where the outer and inner surfaces of the pair of bonded ends 33A, 33B overlap and are joined together when the tube container 30 is produced.

[0034] Therefore, the protective layer 16 is not provided on the pair of bonded ends 33A, 33B of the laminate 10 in the cylindrical body of the tube container. However, if the protective layer 16 has properties such as not interfering with the formation of the body attachment and not being destroyed during heat sealing, the protective layer 16 may be provided on either one or both of the pair of bonding ends 33A, 33B. The protective layer 16 may be partially removed or formed in areas other than the pair of bonding ends 33A and 33B as required.

[0035] On the other hand, the inner surface printed portion 13A provided on the inner surface of the second base material layer 13 is printed on the second base material layer 13, which is smooth and has excellent transparency, and therefore it is possible to produce printing that has excellent cosmetic properties.

[0036] In addition, in FIG. 7, an original roll 10A of a laminate of continuous cylindrical body portions of a plurality of tubular containers before being cut along cutting lines L is shown.

[0037] Next, a method for producing the laminate 10 for the cylindrical body of a tube container will be described with reference to FIG.

[0038] First, printing is applied to the inner surface of the second base material layer 13, and in this manner, an inner surface printed portion 13A made of printing ink is provided on the inner surface of the second base material layer 13.

[0039] Next, the second sealant layer 15 is bonded to the inner surface of the second base material layer 13 by dry lamination (DL).

[0040] Next, the first sealant layer 12 is bonded to the outer surface of the second base layer 13 by dry lamination.

[0041] Next, the first base layer 11 is formed on the outer surface of the first sealant layer 12 by extrusion lamination.

[0042] Next, a protective layer 16 is applied to the outer surface of the first base material layer 11 by printing, and thus a protective layer 16 made of printing is provided on the outer surface of the first base material layer 11. In this manner, a laminate 10 for the cylindrical body of a tube container is obtained.

[0043] The laminate 10 of the cylindrical body of the tube container obtained in this manner is wound into a cylindrical shape, and as described above, both end portions 33A, 33B are overlapped, and the outer and inner surfaces of the laminate 10 of the cylindrical body of the tube container are heat-sealed at both end portions 33A, 33B to form the body sealing portion 32 and produce the cylindrical body portion 31. In this case, the first base material layer 11 and the first sealant layer 12 provided on the outer surface side of the laminate 10 of the cylindrical body of the tube container and the second sealant layer 15 provided on the inner surface side are melted and joined to obtain the cylindrical body 31.

[0044] In the above, the body attachment portion 32 is formed by overlapping, but the end faces of both ends 33A, 33B may be butted together and joined. Furthermore, the joining line formed by butting together as described above may be protected by applying a film to the inner or outer surface of the cylindrical body portion 31. The inner end 33B may be protected by, for example, taping or by folding the end 33B toward the outside of the container (hemming).

[0045] Next, the open portion (upper side) 34A of the cylindrical body 31 is inserted into a mold (not shown), and a shoulder portion 35 and a mouth portion 36 are formed in the open portion (upper side) 34A of the cylindrical body 31 using a method such as compression molding or injection molding, thereby obtaining a tube container 30 (see Figures 4 and 5).

[0046] Next, a cap 37 is attached to the mouth 36 of the tube container 30 manufactured as described above, and a plurality of the tube containers 30 with the caps 37 attached are stored together in a cardboard box. Thereafter, the plurality of tube containers 30 with the caps 37 attached are transported together in the cardboard box.

[0047] As described above, according to the first embodiment of the present invention, the protective layer 16 is provided in an area other than the pair of bonded ends 33A, 33B, and the protective layer 16 has excellent scratch resistance, so that a tube container 30 having excellent scratch resistance can be manufactured.

[0048] <Second embodiment of the present invention> Next, a second embodiment of the present invention will be described with reference to FIG.

[0049] In the second embodiment shown in FIG. 2, a gas barrier layer 14 is attached to the second base layer 13 of the laminate 10 in the cylindrical body portion of a tube container by dry lamination, and a second sealant layer 15 is joined to this gas barrier layer 14 by dry lamination. In the second embodiment shown in Figure 2, the configuration other than that described above is similar to that of the first embodiment shown in Figures 1 and 4 to 6, and the same parts as in the first embodiment are given the same reference numerals and detailed descriptions are omitted.

[0050] In the second embodiment, the laminate 10 of the cylindrical body of the tube container further has a gas barrier layer 14 disposed between the second base material layer 13 and the second sealant layer 15. As the gas barrier layer 14, a metal foil, a film having a base material film and a vapor-deposited film vapor-deposited on the base material film, a film whose material itself has gas barrier properties, or the like can be used.

[0051] Specifically, aluminum foil can be used as the metal foil for the gas barrier layer 14. Aluminum foil is a material that has excellent gas barrier properties, light blocking properties, and excellent cost performance.

[0052] The substrate film on which the vapor-deposited film is provided may be a film or sheet made of various resins, such as polyethylene resins, polypropylene resins, cyclic polyolefin resins, fluorine resins, polystyrene resins, acrylonitrile-styrene copolymers (AS resins), acrylonitrile-butadiene-styrene copolymers (ABS resins), polyvinyl chloride resins, fluorine resins, poly(meth)acrylic resins, polycarbonate resins, polyester resins such as polyethylene terephthalate (PET) and polyethylene naphthalate, polyamide resins such as various nylons, polyimide resins, polyamideimide resins, polyarylphthalate resins, silicone resins, polysulfone resins, polyphenylene sulfide resins, polyethersulfone resins, polyurethane resins, acetal resins, cellulose resins, and others.

[0053] In the present invention, PET is particularly preferred as the substrate film on which the vapor-deposited film is formed, as it has a good balance between performance and cost. In the present invention, it is preferable to use nylon as the base film on which the vapor-deposited film is provided, particularly in situations where mechanical strength is required.

[0054] In addition, a silica vapor-deposited film can be used as the vapor-deposited film vapor-deposited on the base film, and a silica vapor-deposited PET film including the base film and the silica vapor-deposited film can be used as the gas barrier layer 14.

[0055] As the deposited film deposited on the base film, an aluminum deposited film can be used, and as the gas barrier layer 14, an aluminum deposited PET film including a base film and an aluminum deposited film can be used.

[0056] In addition, an aluminum oxide (alumina) vapor-deposited film can be used as the vapor-deposited film vapor-deposited on the base film, and an alumina PET containing a base film and an aluminum oxide (alumina) vapor-deposited film can be used as the gas barrier layer 14.

[0057] Examples of films whose material itself has gas barrier properties include ethylene-vinyl alcohol copolymer resin (EVOH), nylon MXD6, polyacrylonitrile (PAN), and polyvinylidene chloride (PVDC), and these films can be used as the gas barrier layer 14 .

[0058] In the above first and second embodiments, an example is shown in which the first sealant layer 12 is provided between the first base material layer 11 and the second base material layer 13. However, if the first base material layer 11 has sufficient heat sealing function, the first sealant layer 12 does not necessarily have to be provided. Other components not described are similar to those in the first embodiment.

[0059] In the second embodiment, the printed second base layer 13 and the gas barrier layer 14 are separate bodies, but if the gas barrier layer 14 has printability, the gas barrier layer 14 may be printed and the second base layer 13 may be omitted. In such a case, omitting the second base layer 13 makes it possible to reduce costs.

[0060] The printability described above will now be explained. When reverse printing is performed on the inner surface of the gas barrier layer 14, the gas barrier layer 14 is required to have transparency. In addition, since tension is applied to the gas barrier layer 14 during the printing process, the gas barrier layer 14 is required to have a predetermined strength and little elongation.

[0061] Conversely, the advantages of making the printed second base layer 13 and the gas barrier layer 14 separate will be described below. In applications requiring particularly high gas barrier properties, it is desirable not to print on the gas barrier layer 14, since there is a risk that the deposition layer will be damaged in the printing process. For this reason, it is desirable to make the second base layer 13 and the gas barrier layer 14 separate.

[0062] <Third embodiment of the present invention> Next, a third embodiment of the present invention will be described with reference to FIG. To improve the design, a design improving layer 17 made of milky white polyethylene is provided on the inner surface side of the printed second base layer 13. The design improving layer 17 may be in direct contact with and bonded to the second base layer 13, or may be bonded to the second base layer 13 via a light-transmitting layer (not shown).

[0063] Furthermore, in order to improve the bonding strength between the gas barrier layer 14 and each layer in contact with the front and back surfaces of the gas barrier layer 14, adhesive layers 18A and 18B are provided on the front and back surfaces of the gas barrier layer 14. In particular, when an aluminum foil is used for the gas barrier layer 14, it is desirable to provide an adhesive layer in order to improve the bonding strength of the bonding interface of the aluminum foil.

[0064] The layer that ensures the gas barrier property is appropriately selected from the various films described above depending on the performance required for the tube container, cost, and the like. Other components not described are similar to those in the first and second embodiments. EXAMPLES

[0065] Next, a specific embodiment of the present invention will be described.

[0066] Example 1 Example 1 corresponds to the above first embodiment. As the laminate 10 for the cylindrical body of the tube container, a laminate 10 having the following layer structure was prepared.

[0067] Varnished layer 16 / LDPE layer 11 (20 μm) / LLDPE layer 12 (100 μm) / PET layer 13 (12 μm) / Inner printed part 13A / LLDPE layer 15 (210 μm)

[0068] Here, the varnish coating layer 16 is applied to the surface of the LDPE layer 11 by flexographic printing. The LDPE layer 11 is made of low density polyethylene and constitutes the first base material layer 11. The LLDPE layer 12 is made of linear low density polyethylene and constitutes the first sealant layer 12. The PET layer 13 is made of polyethylene terephthalate (PET) and constitutes the second base material layer 13. The LLDPE layer 15 is made of linear low density polyethylene and constitutes the second sealant layer 15. The varnish coating layer 16 can also be applied by gravure printing or with a coater.

[0069] A method for producing the laminate 10 of Example 1 will be described.

[0070] In producing the laminate 10, first, a pattern was printed on the inner surface of a PET film (12 μm) that would become the PET layer 13 using a gravure printer as reverse printing so that the pattern would be a regular pattern when viewed from the outer surface side of the PET film.

[0071] Next, an LLDPE film 12 (100 μm) which would become the first sealant layer 12 was dry laminated to the outer surface of the PET film which would become the PET layer 13 printed by the above procedure, and an LLDPE film 15 (210 μm) which would become the second sealant layer 15 was dry laminated to the inner surface using a dry laminator.

[0072] Next, molten LDPE was extruded into a film using an extruder onto the outer surface of the LLDPE layer 12 on the outer side of the laminate formed by the above procedure, to form an LDPE layer 11 (20 μm) that would become the first base material layer 11. The molten LDPE layer 11 was cooled and solidified on a cooling roll having an appropriate uneven surface, so that the surface of the LDPE layer 11 had an uneven surface suitable for printing.

[0073] Next, ink was applied to the outer surface of the LDPE layer 11 on the outer side of the laminate laminated in the above-mentioned procedure using a flexographic printer to form a varnished layer 16. The ink used was an ultraviolet radiation curable varnish (OP varnish composition: 75-85% by mass of photosensitive monomer, 15-25% by mass of photopolymerization initiator, 1-10% by mass of auxiliary agent, less than 1% by mass of 2,6-di-t-butyl-4-methylphenol), and when the laminate provided with the protective layer 16 made of ultraviolet radiation curable varnish passes through an ultraviolet irradiating section provided on the discharge side of the flexographic printer, the varnish hardens, increasing the hardness of the surface of the protective layer 16, improving scratch resistance, and further reducing the coefficient of friction.

[0074] In order to improve printability and ink adhesion in each of the above printing steps, and to improve laminate strength in each lamination step, the surface of each layer may be appropriately subjected to a surface treatment such as a corona treatment or coated with an anchor coating agent.

[0075] For the tube container 30 in Example 1, the bonding strength between the inside of the pair of bonded ends 33A and the outside of the pair of bonded ends 33B, and the bonding strength between the laminate 10 of the cylindrical body of the tube and the shoulder portion 35 were measured. Both of the bonding strengths were sufficient and at a level that would not cause any problems as a tube container.

[0076] Example 2 Example 2 corresponds to the above-mentioned second embodiment. As the laminate 10 for the cylindrical body of the tube container, a laminate having the following layer structure was prepared.

[0077] Varnish coating layer 16 / LDPE layer 11 (20 μm) / LLDPE layer 12 (100 μm) / PET layer 13 (12 μm) / inner surface printed part 13A / (vapor deposition surface) VM-PET layer 14 (12 μm) / LLDPE layer 15 (210 μm).

[0078] Here, the varnish coating layer 16 is applied to the surface of the LDPE layer 11 by flexographic printing. The LDPE layer 11 is made of low-density polyethylene and constitutes the first base layer 11. The LLDPE layer 12 is made of linear low-density polyethylene and constitutes the first sealant layer 12. The PET layer 13 is made of polyethylene terephthalate (PET) and constitutes the second base layer 13. An inner printed portion 13A is formed on the inner side of the second base layer 13 by gravure printing. The VM-PET layer 14 is made of an aluminum-deposited polyethylene terephthalate layer and constitutes the gas barrier layer 14. The vapor deposition surface of the VM-PET layer 14 is on the outside. By placing the vapor deposition surface on the outside, the attack of the contents on the vapor deposition surface is mitigated compared to when the vapor deposition surface is on the inside, and the vapor deposition film may be less deteriorated. The LLDPE layer 15 is made of linear low-density polyethylene and constitutes the second sealant layer 15.

[0079] A method for producing the laminate 10 of Example 2 will be described. In producing the laminate 10, first, a pattern was printed on the inner surface of a PET film (12 μm) that would become the PET layer 13 using a gravure printer as reverse printing so that the pattern would be a regular pattern when viewed from the outer surface side of the PET film.

[0080] Next, a VM-PET layer 14 (12 μm) which will become the gas barrier layer 14 is sequentially formed on the inner surface of the PET film printed in the above-mentioned procedure, and an LLDPE film 15 (210 μm) which will become the second sealant layer 15 is further dry laminated (DL) on the inner surface of the gas barrier layer 14. The vapor deposition surface of the VM-PET layer 14 faces outward.

[0081] Next, an LLDPE film 12 (100 μm) which becomes the first sealant layer 12 is dry laminated by a dry laminator onto the outer surface of the PET film which becomes the PET layer 13 of the laminate formed by the above procedure.

[0082] Next, molten LDPE is extruded into a film shape using an extruder onto the outer surface of the LLDPE film 12 on the outer side of the laminate formed by the above procedure, to form an LDPE layer 11 (20 μm) that will become the first base material layer 11. The surface of the cooling roll that cools and solidifies the molten film-like LDPE layer 11 has an appropriate uneven shape, so that the surface of the LDPE layer 11 has an uneven shape suitable for printing.

[0083] Next, ink is applied to the outer surface of the LDPE film 11 on the outer side of the laminate laminated in the above-mentioned procedure using a flexographic printer to form a varnished layer 16. The ink used is an ultraviolet-ray curable varnish (the same as in Example 1), and when the laminate having the protective layer 16 made of ultraviolet-ray curable varnish passes through an ultraviolet ray irradiation section provided on the discharge side of the flexographic printer, the varnish hardens, increasing the hardness of the surface of the protective layer 16, improving scratch resistance, and further reducing the coefficient of friction.

[0084] For the tube container 30 in Example 2, the bonding strength between the inner side of 33A and the outer side of 33B, which are a pair of bonded ends, and the bonding strength between the laminate 10 of the cylindrical body of the tube and the shoulder portion 35 were measured. Both of the bonding strengths were sufficient and at a level that would not cause any problems as a tube container.

[0085] Example 3 Example 3 corresponds to the above-mentioned third embodiment. As the laminate 10 for the cylindrical body of the tube container, a laminate having the following layer structure was prepared.

[0086] Varnish coating layer 16 / LDPE layer 11 (30μm) / LLDPE 12A (60μm) / LDPE layer 12B (20μm) / PET layer 13 (12μm) / inner printed part 13A (anchor coat) / milky white LLDPE layer 17 (100μm) / EMAA layer 18A (20μm) / aluminum foil 14 (10μm) / EMAA layer 18B (30μm) / LLDPE 15 (100μm).

[0087] Here, the varnish coating layer 16 is applied to the surface of the LDPE layer 11 by flexographic printing. The LDPE layer 11 is made of low density polyethylene and constitutes the first base layer 11. The LLDPE layer 12 is made of linear low density polyethylene and constitutes the first sealant layer 12. The PET layer 13 is made of polyethylene terephthalate (PET) and constitutes the second base layer 13. An inner printed portion 13A is formed on the inside of the second base layer 13 by gravure printing. The milky white LLDPE layer 17 is made of linear low density polyethylene colored milky white and constitutes the design improving layer 17. The EMAA layer 18A is made of ethylene-methacrylic acid copolymer and constitutes the adhesive layer 18A. The aluminum foil 14 constitutes the gas barrier layer 14. The EMAA layer 18B is made of ethylene-methacrylic acid copolymer and constitutes the adhesive layer 18B. The LLDPE 15 is made of linear low density polyethylene and constitutes the second sealant layer 15.

[0088] A method for producing the laminate 10 of Example 3 will be described.

[0089] In producing the laminate 10, first, a pattern was printed on the inner surface of a PET film (12 μm) that would become the PET layer 13 using a gravure printer as reverse printing so that the pattern would be a regular pattern when viewed from the outer surface side of the PET film.

[0090] Next, a film previously prepared to become the milky white LLDPE layer 17 is dry laminated by a dry laminator onto the inner surface of the PET film that will become the PET layer 13 printed in the above procedure.

[0091] Next, a molten EMAA layer 18A is extruded in a film shape using an extruder onto the inner surface of the LLDPE layer 17 of the laminate formed by the above-mentioned procedure, and while the EMAA layer 18A that will become the adhesive layer 18A is in a molten state, the aluminum foil 14 that will become the gas barrier layer 14 is bonded thereto. Thereafter, the EMAA layer 18A is cooled and solidified and bonded to the aluminum foil 14.

[0092] Following the above process, a molten EMAA layer 18B is extruded in a film shape onto the inner surface of the aluminum foil 14, and while the EMAA layer 18B that will become the adhesive layer 18B is in a molten state, a previously prepared LLDPE film that will become the LLDPE layer 15 is bonded, and then the EMAA layer 18B is cooled to solidify and adhere to the LLDPE layer 15. EMAA has stronger adhesive strength to metals than LDPE, and is effective in improving the laminate strength of the aluminum foil.

[0093] Next, the outer surface of the PET film of the laminate laminated in the above-mentioned procedure is coated with an anchor coat using a polyurethane-based anchor coat agent, and then the molten LDPE layer 12B is extruded into a film using an extruder, and a previously prepared film that will become the LLDPE layer 12A is bonded to the outer surface side of the LDPE layer 12B while the LDPE layer 12B that will become the adhesive layer 12B is in a molten state. Thereafter, the LDPE layer 12B is cooled and solidifies and adheres to the LLDPE layer 12A.

[0094] Following the above process, a molten LDPE layer 11 is extruded into a film on the outer surface of the LLDPE layer 12A, and then cooled to form an LDPE layer 11 (20 μm) that becomes the first base layer 11. The surface of the cooling roll that cools and solidifies the molten LDPE layer 11 in a film form has an appropriate uneven shape, so that the surface of the LDPE layer 11 has an uneven shape suitable for printing.

[0095] Next, ink is applied to the outer surface of the LDPE layer 11 on the outer side of the laminate laminated in the above-mentioned procedure using a flexographic printer to form a varnished layer 16. The ink used is an ultraviolet-ray curable varnish (the same as in Example 1), and when the laminate with the protective layer 16 made of ultraviolet-ray curable varnish passes through an ultraviolet ray irradiation section provided on the discharge side of the flexographic printer, the varnish hardens, increasing the hardness of the surface of the protective layer 16, improving scratch resistance, and further reducing the coefficient of friction.

[0096] For the tube container 30 in Example 3, the bonding strength between the inner side of 33A and the outer side of 33B, which are a pair of bonded ends, and the bonding strength between the laminate 10 of the cylindrical body of the tube and the shoulder portion 35 were measured. Both of the bonding strengths were sufficient and at a level that would not cause any problems as a tube container.

[0097] (Comparative Example) The comparative example is a tube container manufactured by the same method and with the same configuration as in Example 3, except that it does not have the protective layer 16 made of the varnish coating layer 16 .

[0098] (Comparison and evaluation of various examples and comparative examples) For the samples of the various examples and the samples of the comparative examples, a friction coefficient measurement test, a friction test (scratch resistance test), and a transportation test were carried out.

[0099] (Measurement of surface friction coefficient) The friction coefficients of the surfaces of the various examples and comparative examples were measured, and the results are shown in Table 1. The static and dynamic friction coefficients were measured in accordance with JIS K-7125 using a measuring device, TR-2, manufactured by Toyo Seiki Seisakusho Co., Ltd. The number of tests was n=3, and the test speed was 100 mm / min.

[0100] The measurement results are shown in Table 1. The surface of the laminate of the cylindrical body of the tube container, which is listed in the item of friction surfaces in Table 1, was measured for the friction coefficient using the same combination of materials, and it was assumed that the tubes would rub against each other when the tube containers are transported. The metal surface described in the section on friction target surface is assumed to come into contact with metal parts during the transport process of filling and packaging tube containers. The metal surface used in the friction measurement this time is stainless steel, and has a flat, smooth surface like a mirror.

[0101] [Table 1]

[0102] From Table 1, we can see the following: In the case of the laminated surface of the cylindrical body of the tube container, the static and dynamic friction coefficients are smaller in the various examples than in the comparative example, and the frictional force generated on the tube container surface is smaller in the various examples, resulting in less damage to the surface. As a result, the surface of the various examples is less likely to be scratched during transportation of the tube container.

[0103] When the friction target surface is a metal surface, the static and dynamic friction coefficients are smaller in the various Examples than in the Comparative Example, and the frictional force generated on the tube container surface is smaller in the various Examples, resulting in less damage to the surface. As a result, when contact is made with metal parts during the transport process during the filling and packaging of tube containers, the surfaces of the various Examples are less likely to be scratched.

[0104] In addition, in a conveyor chain with a plate on top, the tops of the caps of tube containers are placed on the plate with the caps facing down, and the tube containers are conveyed only by the friction between the tops of the caps and the conveyor plate, while the cylindrical bodies of the tube containers are regulated by a metal guide attached to the conveyor. For tube containers with a small coefficient of friction in the cylindrical bodies, the frictional force exerted by the guide on the cylindrical bodies of the tube containers is small, so that the tube containers are less likely to get caught or fall over on the line, resulting in less disruption to production.

[0105] (Evaluation of surface scratch resistance) The scratch resistance of the surface was evaluated by the Gakushin friction test (JIS L-0849). The measuring device was FR-2 manufactured by Suga Test Instruments Co., Ltd.

[0106] When conducting a friction test between the laminates, a strip-shaped (30 mm wide) laminate of the cylindrical body part of a tube container was fixed to the lower test piece stand, and a strip-shaped (30 mm wide) laminate of the cylindrical body part of a tube container made of the same material was attached to the upper friction element. When conducting a friction test between the laminate and a metal plate, a metal plate was attached to the upper friction element and the friction element was slid. The metal plate used in the Gakushin friction test this time was stainless steel, and had a smooth mirror-like surface. The weight used was 200 g.

[0107] The Gakushin friction test was repeated 100 and 300 times, and the number of scratches on the surface of the laminate was visually counted. Samples with 20 or more scratches were rated as × (bad), samples with 10 to less than 20 scratches were rated as △ (slightly bad), and samples with less than 10 scratches were rated as ○ (good).

[0108] As with the measurement of the coefficient of friction, the friction coefficient was measured using the same combination of materials as the surface of the laminate of the cylindrical body of the tube container described in the section on friction target surfaces, simulating the friction between tubes when the tube container is transported. The metal surfaces that are subject to friction are assumed to come into contact with metal parts such as guide parts during the transport process when filling and packaging tube containers.

[0109] [Table 2]

[0110] From Table 2, we can see the following: In a friction test of the surfaces of the laminates of the cylindrical body of the tube container against each other, the comparative example was △ (slightly poor) after 100 frictions and × (poor) after 300 frictions. In addition, the various examples were ○ (good) after 100 frictions and ○ (good) after 300 frictions. From this, it can be seen that the various Examples are less susceptible to scratches when the tube containers are rubbed against each other, and have improved scratch resistance compared to the Comparative Example.

[0111] In addition, in a friction test between the surface of the laminate of the cylindrical body of the tube container and a metal surface, the comparative example was ◯ (good) after 100 frictions and △ (slightly poor) after 300 frictions. In addition, in Example 3, the comparative example was ◯ (good) after 100 frictions and ◯ (good) after 300 frictions. This shows that the various Examples are less susceptible to scratches when the surface of the tube container rubs against a metal part, and have improved scratch resistance compared to the Comparative Example.

[0112] (Evaluation of scratch resistance through actual transportation testing) An actual transportation test was carried out on the samples of Example 3 and Comparative Example. The prepared samples were filled with water to prepare packaged products, and 10 of each were packed in a cardboard box and transported round trip between Shinjuku-ku, Tokyo and Kyotanabe-shi, Kyoto Prefecture by home delivery (land route). The one-way distance was about 475 km, and the total distance was about 950 km.

[0113] After arrival, the cardboard box was opened and the tube container was visually observed. The number of scratches on the surface of the cylindrical body of the tube container was counted. The test result was rated as × (bad) for tube containers with 20 or more scratches, △ (slightly bad) for tube containers with 10 to less than 20 scratches, and ◯ (good) for tube containers with less than 10 scratches.

[0114] The results are shown in Table 3. The damage to each of the 10 tube containers was similar and there was no difference.

[0115] [Table 3]

[0116] The following can be seen from Table 3. The sample of the comparative example had many scratches and was poor in appearance, whereas the sample of the example 3 had less than 10 scratches and was good. From this, it was found that in the actual transportation test, the tube container of Example 3 had excellent scratch resistance and was able to maintain its aesthetic appeal. [Industrial Applicability]

[0117] According to the present invention, a tube container having a low coefficient of friction on the surface of the laminate of the cylindrical body of the tube container can be provided, which prevents the tube container from getting caught or falling on the filling and packaging line for the packaged products of the tube container, and enables the filling and packaging line for the packaged products of the tube container to operate stably, contributing to improved quality and reduced production costs. In addition, since the outer surface of the tube container is not easily scratched, it is possible to display beautiful products in stores, stimulating purchasing desire. [Explanation of symbols]

[0118] 10 Laminated body of a tube container 10A Original roll of laminate for cylindrical body of tube container 11 First base layer 12 First sealant layer 12A Part of the first sealant layer 12B Part of the first sealant layer (also serves as adhesive layer) 13 Second base layer 13A Inner printed section 14 Gas barrier layer 15 Second sealant layer 16 Protective layer 17 Design enhancement layer 18A adhesive layer 18B Adhesive layer 30 Tube Container 30A Tube Container Packaging Products 31 Cylindrical body 32 Body attachment section 33A The edge of the joint that will be on the outside when the body is pasted 33B The end of the joint that will be the inside when the body is pasted 34A opening (upper side) 34B opening (lower side) 35 Shoulder 36 Mouth 37 Cap 38 Contents 39 Bottom seal L cutting line

Claims

[Claim 1] A tube container comprising a body portion having a pair of joined ends and a shoulder portion, The laminate of the body portion includes at least a first base material layer, a first sealant layer, a second base material layer, and a second sealant layer laminated in this order from the outer surface to the inner surface, the first substrate layer is low density polyethylene, the first sealant layer is linear low density polyethylene, the first substrate layer and the first sealant layer are adjacent to each other; The thickness of the first base layer is smaller than the thickness of the first sealant layer, A protective layer is provided on the entire surface or at least a part of the outer surface of the first base material layer, The protective layer is a printing ink containing an ultraviolet radiation curable varnish, The arithmetic mean height (Sa) of the surface of the first base layer is 0.1 to 1.0 μm.

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