Tube container

Abstract

To provide a tube container excellent in recyclability.SOLUTION: The tube container of the present invention comprises a tubular body portion having one closed end and a spout portion attached to the other end of the body portion, the body portion and the spout portion together constitute 90% by mass or more of polypropylene, and the film constituting the body portion has a loop stiffness of 120 to 200 mN / 15 mm.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a tube container. [Background technology]

[0002] Tube containers made primarily of resin are widely used as packaging materials for pharmaceuticals, cosmetics, food, etc. For example, Patent Document 1 describes a tube container consisting of a dispensing unit for extracting the contents and a body portion welded to the dispensing unit and containing the contents. Patent Document 1 also describes that the inner layer of the film constituting the body portion is made non-adsorbent to the contents, and that the intermediate layer of the film constituting the body portion is made a gas barrier layer containing a gas barrier substance, thereby imparting gas barrier properties. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-199280 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, tube containers have generally been discarded after use, but in recent years, from the viewpoint of reducing the environmental load, there has been a demand for tube containers that can be easily recycled. As described in Patent Document 1, high performance tube containers have been achieved by combining various materials to form tube containers. However, when a tube container contains different types of materials, there are problems in terms of ease of recycling, such as the need to separate the materials and difficulty in recycling.

[0005] Therefore, an object of the present invention is to provide a tube container that is highly recyclable. [Means for solving the problem]

[0006] The tube container according to the present invention comprises a tubular body portion having one closed end and a spout portion attached to the other end of the body portion, and the body portion and the spout portion contain polypropylene in a total amount of 90% by mass or more, The film constituting the body portion has at least one layer of stretched polypropylene and a layer of unstretched polypropylene on only one of the two surfaces of the film, and has a loop stiffness of 120 to 200 mN / 15 mm. The body portion is a molded body obtained by molding a film having a pair of parallel edges into a cylindrical shape, and the inner surfaces of the band-shaped portions including each of the pair of edges are joined together. do. [Effects of the Invention]

[0007] According to the present invention, a tube container with excellent recyclability can be provided. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a front view showing a schematic configuration of a tube container according to a first embodiment. [Figure 2] Cross-sectional view along line II-II shown in Figure 1 [Figure 3] FIG. 2 is a cross-sectional view showing a modified example of the tube container shown in FIG. 1. [Figure 4] Top view of the tube container shown in Figure 1 [Figure 5] End view along the VV line shown in Figure 4 [Figure 6] A cross-sectional view showing an example of a film constituting the body of a tube container. [Figure 7] FIG. 1 is a cross-sectional view showing another example of a film constituting the body of a tube container. [Figure 8] FIG. 1 is a cross-sectional view showing another example of a film constituting the body of a tube container. [Figure 9] FIG. 2 is a diagram showing an example of how to use the tube container shown in FIG. 1. [Figure 10] FIG. 10 is a front view showing a schematic configuration of a tube container according to a second embodiment. [Figure 11] FIG. 10 is a cross-sectional view showing a schematic configuration of a tube container according to a third embodiment. [Figure 12] Cross-sectional view of the tube container shown in Figure 11 [Figure 13] A cross-sectional view showing an example of a gas barrier laminate that can be used for the body of a tube container. [Figure 14]FIG. 10 is a cross-sectional view showing an example of a layer structure of materials that can be used for the body portion of a tube container according to a modified example. [Figure 15] FIG. 10 is a cross-sectional view showing another example of a layer structure of materials that can be used for the body portion of the tube container according to the modified example. DETAILED DESCRIPTION OF THE INVENTION

[0009] (First embodiment) Fig. 1 is a front view showing a schematic configuration of a tube container according to a first embodiment, and Fig. 2 is a cross-sectional view taken along line II-II shown in Fig. 1. Fig. 3 is a cross-sectional view showing a modified example of the tube container shown in Fig. 1. In Fig. 1, only the cap is shown in a partially cutaway view.

[0010] The tube container 100 comprises a tube-shaped body 1 and a spout 2 attached to the body 1.

[0011] The body 1 is a member for containing contents and can be formed by molding a film having a pair of approximately parallel edges into a cylindrical shape. The body 1 is formed into a cylindrical shape by welding the inner surfaces of strip-shaped portions of the film, each including a pair of edges, together in a palm-to-palm fashion, as shown in FIG. 2 . One end 5a (the lower end in FIG. 1 ) of the body 1 is closed by heat sealing, and the vicinity of the other end 5b (the upper end in FIG. 1 ) is welded to the spout 2. The bonded portion 7 formed on the body 1 by bonding the edge portions of the film may be folded and bonded to the body 1 in a state that fits along the outer surface of the body 1, as shown in FIG. 3 . The method for bonding the bonded portion 7 to the body 1 is not particularly limited; they may be welded to each other via a heat-sealable resin applied to the entire or partial surface of the film constituting the body 1, or they may be bonded to each other via an adhesive such as a hot melt. The bonding method of the body portion 1 shown in Figures 2 and 3 is an example, and the outer surface of a band-shaped region including one edge of the film constituting the body portion 1 may be bonded to the inner surface of a band-shaped region including the other edge of the film.

[0012] The spout 2 is a member for extracting the contents contained in the body 1 to the outside, and includes a cylindrical spout 3 and a flange 4. The flange 4 is connected to one end 6a (the lower end in FIG. 1 ) of the body 3 and is a flat plate-like portion extending outward from the body 3. In this embodiment, the flange 4 is formed so as to extend in a direction perpendicular to the axial direction of the body 3 (the left-right direction in FIG. 1 ). In this embodiment, the flange 4 is formed in an annular shape, but the shape of the flange 4 is not limited as long as it can be joined to the body 1, and may be elliptical, oval, polygonal, or the like.

[0013] As shown in Fig. 1, the tube container 100 may further include a screw cap 10 that can be attached and detached by screwing onto the cylindrical pouring portion 3 of the pouring outlet portion 2. When the tube container 100 includes the screw cap 10, the tube container 100 can be easily resealed after being opened. There are no particular restrictions on the material of the screw cap 10, but polypropylene is preferred because it can be recycled (recycled) as a single material together with the tube container 100. However, the screw cap 10 is optional, and the tube container 100 does not necessarily have to include the screw cap 10.

[0014] Further, at the end 6b of the dispensing tube portion 3, when the tube container 100 is in an unopened state, The film enclosing 3 may be sealed.

[0015] 4 is a top view of the tube container shown in FIG. 1, and FIG. 5 is a cross-sectional view taken along the line VV shown in FIG.

[0016] 4 and 5, the inner surface of a predetermined range from end 6b of body 1 is folded and welded to the outer surface of flange 4, i.e., the surface of flange 4 closest to end 6b. Multiple pleats 8 are formed on the outer surface of flange 4 by folding the film that constitutes body 1. Welding of body 1 to flange 4 can be performed, for example, using a processing device with multiple claws arranged intermittently around the circumferential direction of flange 4, by pressing a predetermined range of film from end 6b of body 1 against flange 4 with the multiple claws, and then using a ring-shaped welding device to crush the film protruding from between adjacent claws, thereby folding the predetermined range of film from end 6b of body 1, and then using the welding device to apply heat and pressure while the claws pressing the film are retracted.

[0017] The tube container 100 according to this embodiment contains polypropylene in a total of 90% by mass or more of the body portion 1 and the spout portion 2. In other words, 90% by mass or more of the tube container 100 is made of polypropylene.

[0018] More specifically, the outlet 2 is formed from a resin material primarily composed of polypropylene. The molding method for the outlet 2 is not particularly limited, but examples include injection molding, thermoforming (e.g., vacuum forming or hot plate compression molding), and compression molding. The resin material for forming the outlet 2 may consist solely of polypropylene, or may contain small amounts of barrier resins and additives commonly used in resin molding, such as pigments, mold release agents, antioxidants, and clarifying agents. However, when additives are blended into the resin material for the outlet 2, the blending amounts of materials other than polypropylene are adjusted so that the proportion of polypropylene in the total mass of the container is 90% or more. Examples of barrier resins blended with polypropylene include polyvinyl alcohol (PVOH) and ethylene-vinyl alcohol copolymer (EVOH).

[0019] The body 1 is formed of a film mainly made of polypropylene film. The film constituting the body preferably has at least a layer of stretched polypropylene and a layer of unstretched polypropylene. Specific examples of the film constituting the body 1 will be described below.

[0020] 6 to 8 are cross-sectional views showing examples of films that form the body of a tube container.

[0021] Film 11 shown in Fig. 6 has a layer 16 of stretched polypropylene laminated on a layer 15 of unstretched polypropylene. Film 12 shown in Fig. 7 has a layer 17 of stretched polypropylene with barrier properties laminated on a layer 15 of unstretched polypropylene. Film 13 shown in Fig. 8 has a layer 17 of stretched polypropylene with barrier properties and a layer 16 of stretched polypropylene laminated in this order on a layer 15 of unstretched polypropylene. Films 11 to 13 shown in Figs. 6 to 8 can be formed by bonding the films that make up each layer together, for example, by dry lamination.

[0022] The unstretched polypropylene layer 15 functions as a sealant, imparting heat-sealability to the film that constitutes the body 1. By using the unstretched polypropylene layer 15 as a sealant, the body can be easily welded to the spout 2, which is made of a resin material whose main component is polypropylene. The thickness of the unstretched polypropylene layer 15 is preferably 15 to 150 μm. If the thickness of the unstretched polypropylene layer 15 is less than 15 μm, it will be difficult to fill in the unevenness (see FIG. 5) that occurs when the films are overlapped when welding the body 1 to the spout 2 with molten unstretched polypropylene, resulting in insufficient welding or a poor appearance. Furthermore, if the total thickness of the unstretched polypropylene layer 15 exceeds 150 μm, the manufacturing cost and the amount of resin used will increase, which is also undesirable.

[0023] The stretched polypropylene layers 16 and 17 impart strength and stiffness to the body portion 1. The total thickness of the stretched polypropylene layers 16 and 17 is preferably 15 to 200 μm. By providing stretched polypropylene layers 16 and / or 17 within this thickness range, the loop stiffness of the film can be increased to 120 mN or more, allowing a tubular container having a cylindrical body portion 1 to stably maintain its tubular shape. Loop stiffness is the load required to crush a strip of film cut into a loop by a predetermined amount in the diametrical direction of the loop, and corresponds to the crushing resistance of the loop. Furthermore, when a tubular container 100 is produced using a film having stretched polypropylene layers 16 and / or 17, the tubular container is not too soft when filled with contents, resulting in excellent handleability of the filled tubular container. A total thickness of the stretched polypropylene layers 16 and 17 less than 15 μm is not preferable because it lacks the strength and stiffness required for the tubular container 100. Furthermore, if the total thickness of the stretched polypropylene layers 16 and 17 exceeds 200 μm, the film forming the body 1 becomes too hard, making it difficult to weld to the spout 2, and this is not desirable because it increases manufacturing costs and the amount of resin used.

[0024] The layer 17 of stretched polypropylene having barrier properties is formed from a gas barrier laminate in which a barrier layer made of a thin film of an inorganic compound such as silica or alumina is laminated onto a stretched polypropylene film, or a gas barrier laminate in which a barrier layer made of a barrier resin such as PVA or EVOH and a barrier coating agent containing an inorganic filler is laminated onto the layer 17. By providing the layer 17 of stretched polypropylene having barrier properties, it is possible to impart gas barrier properties to the body 1 while increasing the polypropylene ratio of the film that constitutes the body 1.

[0025] However, the film constituting the body portion 1 only needs to have at least an unstretched polypropylene layer 15 and an oriented polypropylene layer 16, as in the film 11 shown in FIG. 6 . Having two layers of unstretched polypropylene and oriented polypropylene in the film constituting the body portion 1 can provide the strength, stiffness, and heat-sealability required of a tube container to the body portion 1. However, depending on the contents and intended use of the tube container, the above-mentioned barrier layer or an oriented polypropylene layer can be further provided. The barrier layer may be laminated on the unstretched polypropylene layer, or on both the unstretched polypropylene layer and the oriented polypropylene layer. Furthermore, in addition to the barrier layer, a printing ink layer, an adhesive, etc. can be appropriately laminated on one or both of the unstretched polypropylene layer and the oriented polypropylene layer.

[0026] When 90% by mass or more of the total of the body 1 and the spout 2 is made of polypropylene, the entire tube container 100 can be regarded as a single resin, and therefore the used tube container 100 can be recycled as polypropylene. From the viewpoint of further promoting the mono-materialization of the tube container 100, the proportion of polypropylene in the total of the body 1 and the spout 2 is preferably 95% by mass or more, and more preferably 99% or more.

[0027] Although there are no particular limitations on the thickness (total thickness) of the film that constitutes the body portion 1, it is preferably 30 to 250 μm. If the thickness of the film that constitutes the body portion 1 is within this range, the body portion 1 can be easily processed into a cylindrical shape using a bag-making machine, a pillow stick packaging machine, or the like.

[0028] FIG. 9 is a diagram showing an example of a method of using the tube container shown in FIG.

[0029] As described above, the tube container 100 according to this embodiment is configured by welding a predetermined area from the end 5b of the body 1 to the outer surface of the flange 4 of the spout 2. If a film having a thickness of 30 to 250 μm is used, it is possible to fold the body 1 along the outer periphery of the flange 4, as shown in Fig. 9. Therefore, when the content of the tube container 100 becomes low, the content can be easily squeezed out by folding the body 1 along the outer periphery of the flange 4, as shown in Fig. 9. If the body 1 is made of a film having a thickness of 30 to 250 μm, it becomes even easier to squeeze out the content by folding the body 1.

[0030] Furthermore, in the tube container 100 according to this embodiment, the flange portion 4 has a flat plate shape that is perpendicular to the central axis of the cylindrical pouring portion 3, and therefore no space in which the contents remain is formed by the flange portion 4. Therefore, by pushing down the pouring outlet portion 2 in the direction of the arrow in Figure 9 and making the flange portion 4 and the body portion 1 substantially flat, the contents can be squeezed out completely.

[0031] In contrast, in the case of a typical laminated tube, the portion corresponding to the flange of the spout is formed in a tapered shape, so even when folded as in Figure 9, the contents are likely to remain in the space created by the tapered shape of the spout. Furthermore, a typical laminated tube has a cylindrical peripheral wall portion that is coaxial with the tubular pouring portion around the outer periphery of the flange of the spout, and one end of the body portion is welded to the outer peripheral surface of this peripheral wall portion. Therefore, the contents are likely to remain in the space created by the peripheral wall portion to which the body portion is welded.

[0032] As described above, the tube container 100 according to this embodiment has a combined total of 90% by mass or more of the body 1 and the spout 2 formed from polypropylene, and therefore can be recycled as polypropylene without separating the body 1 or the spout 2. Therefore, according to this embodiment, a tube container 100 with excellent recyclability can be realized.

[0033] Furthermore, by forming the body 1 from a film containing a layer of oriented polypropylene and a layer of unoriented polypropylene, it is possible to impart the strength, stiffness, and heat-sealability required of a tube container to the body 1. Furthermore, in this embodiment, the spout 2 is formed from a resin material containing polypropylene as the main component, which provides excellent welding between the flange 4 of the spout 2 and the unoriented polypropylene layer (sealant layer) of the film that constitutes the body 1.

[0034] Furthermore, by laminating a barrier layer on the stretched polypropylene layer of the film that constitutes the body portion 1, it is possible to obtain a tubular container 100 that has excellent gas barrier properties.

[0035] Furthermore, when the body 1 is formed from a film having a thickness of 30 to 250 μm, the body 1 can be easily processed using a bag-making machine, pillow stick packaging machine, etc., improving the ease of squeezing the contents. In addition, a film having a thickness of 30 to 250 μm allows for gravure printing, which can express fine shading, so that the outer surface of the body 1 can be printed with a highly decorative design.

[0036] The body 1 is formed into a cylindrical shape by rolling up a film having a pair of approximately parallel edges and joining the inner surfaces of the band-shaped portions including each of the pair of edges. When the body 1 is formed in this manner, it is only necessary to provide a sealant layer on one side of the film, which allows the film constituting the body 1 to be made thinner and the amount of resin to be reduced.

[0037] As explained in Figure 9, the flange portion 4 of the spout 2 is formed in a flat plate shape that is perpendicular to the central axis of the tubular pouring portion 3, and the inner surface of the body 1 is welded to the outer surface of the flange portion 4 (the surface on the end 6b side of the tubular pouring portion 3), making it easier to squeeze out the contents by folding the body 1 and reducing the amount of contents remaining inside the spout 2.

[0038] The second and third embodiments will be described below. In the second and third embodiments, The same parts as those in the first embodiment are denoted by the same reference numerals in the drawings, and the description thereof will be omitted, and the description will focus on the differences from the first embodiment.

[0039] (Second embodiment) FIG. 11 is a front view showing a schematic configuration of a tube container according to the second embodiment.

[0040] The tube container 200 according to this embodiment differs from the tube container 100 according to the first embodiment in that the flange portion 25 of the spout portion 2 has a tapered shape. Even when the flange portion 25 of the spout portion 2 has a tapered shape, by using polypropylene for a total of 90% by mass or more of the body portion 1 and the spout portion 2, it is possible to realize a tube container 200 with excellent recyclability, as in the first embodiment.

[0041] (Third embodiment) FIG. 12 is a cross-sectional view showing a schematic configuration of a tube container according to the third embodiment, and FIG. 13 is a cross-sectional view of the tube container shown in FIG.

[0042] The tube container 300 according to this embodiment differs from the tube container 100 according to the first embodiment in that a partition wall 26 is provided inside the cylindrical pouring portion 3 of the pouring outlet portion 2, and that a hinge cap 29 that can be opened and closed via a hinge is provided on the pouring outlet portion 2. Note that the tube container 300 does not necessarily have to include the hinge cap 29.

[0043] The partition 26 inside the cylindrical pouring portion 3 is a component provided to keep the interior of the tube container 300 sealed when the tube container 300 is in an unopened state. The partition 26 has a circular half cut 27. A pull ring 28 is connected to the portion of the partition 26 surrounded by the half cut 27. The pull ring 28 is composed of an annular ring portion 30 and a connecting portion 31 that connects the ring portion 30 and the partition 26. When opening the tube container 300, the user pulls the pull ring 28 to break the half cut 27 portion of the partition 26, thereby removing the portion of the partition 26 surrounded by the half cut 27 and forming an opening for pouring the contents from the body 1 into the cylindrical pouring portion 3.

[0044] Like the screw cap 10 in the first embodiment, the hinge cap 29 is a member for resealing the tube container 300. In this embodiment, the hinge cap 29 is attached to the spout 2 by fitting an inner ring provided on the hinge cap 29 into the spout 2, but the hinge cap 29 may also be attached to the spout 2 by screwing.

[0045] In this embodiment, too, by using polypropylene for a total of 90% by mass or more of the body 1 and the spout 2, it is possible to realize a tube container 300 with excellent recyclability, just like the first embodiment.

[0046] (Other variations) Fig. 13 is a cross-sectional view showing an example of a gas barrier laminate that can be used for the body of a tube container. The gas barrier laminate shown in Fig. 13 can be used to form the gas barrier layer 17 shown in Figs. 7 and 8, for example.

[0047] The gas barrier laminate 19 is obtained by laminating, in this order, a resin layer 21 having vinyl alcohol units, an inorganic thin film layer 22, and a resin layer 23 having vinyl alcohol units on a base layer 20. The resin layer 21 having vinyl alcohol units, the inorganic thin film layer 22, and the resin layer 23 having vinyl alcohol units correspond to a barrier layer.

[0048] The base layer 20 is a layer primarily composed of polyolefin. Examples of polyolefins include polyethylene (PE), polypropylene (PP), polybutene (PB), and cycloolefin polymers. Other examples of polyolefins include acid-modified polyolefins obtained by graft-modifying polyolefins with unsaturated carboxylic acids, acid anhydrides of unsaturated carboxylic acids, esters of unsaturated carboxylic acids, and the like. Small amounts of ethylene or butene may be blended as raw material monomers during polypropylene synthesis. In the present invention, the base layer 20 is preferably formed from polypropylene, since the proportion of polypropylene constituting the tubular container 100 is 90% by mass or more of the combined total of the body 1 and the spout 2. However, as long as the proportion of polypropylene is 90% by mass or more of the combined total of the body 1 and the spout 2, a film made of a polyolefin other than polypropylene can be used for the base layer 20.

[0049] The film constituting the base layer 20 may be either a stretched film or an unstretched film. However, from the viewpoints of impact resistance, heat resistance, water resistance, dimensional stability, etc., the film constituting the base layer 20 is preferably a stretched film. The stretching method is not particularly limited, and any method may be used as long as it can provide a dimensionally stable film, such as stretching by inflation, uniaxial stretching, or biaxial stretching.

[0050] The thickness of the base layer 20 is not particularly limited, but from the viewpoint of obtaining excellent impact resistance and excellent gas barrier properties, it is preferably 9 to 100 μm, and more preferably 15 to 30 μm.

[0051] The film constituting the base material layer 20 may be subjected to various pretreatments such as corona treatment, plasma treatment, and flame treatment on its lamination surface within a range that does not impair its barrier performance, or may be provided with a coating layer such as an easy-adhesion layer.

[0052] The film constituting the base layer 20 may contain additives such as antistatic agents, ultraviolet absorbers, plasticizers, and lubricants, if necessary.

[0053] The resin layer having vinyl alcohol units (hereinafter simply referred to as "resin layer") 21 is a layer containing PVA or EVOH as a main component. From the viewpoint of heat resistance and gas barrier properties, EVOH is preferably used.

[0054] Examples of PVA include resins obtained by homopolymerizing vinyl esters such as vinyl acetate, vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate, and vinyl versatate, followed by saponification.

[0055] The PVA may be a copolymerized or post-modified modified PVA. Copolymerized modified PVA can be obtained, for example, by copolymerizing a vinyl ester with an unsaturated monomer copolymerizable with the vinyl ester, followed by saponification. Post-modified PVA can be obtained by copolymerizing the PVA obtained by saponifying the vinyl ester with an unsaturated monomer in the presence of a polymerization catalyst. The amount of modification in the modified PVA can be less than 50 mol % in order to achieve sufficient gas barrier properties, and can be 10 mol % or more in order to obtain the effect of modification.

[0056] Examples of the unsaturated monomer include olefins such as ethylene, propylene, isobutylene, α-octene, α-dodecene, and α-octadecene; hydroxy group-containing α-olefins such as 3-buten-1-ol, 4-pentyn-1-ol, and 5-hexen-1-ol; acrylic acid, methacrylic acid, crotonic acid, maleic acid, maleic anhydride, and itaconic acid. and undecylenic acid; nitriles such as acrylonitrile and methacrylonitrile; amides such as diacetone acrylamide, acrylamide, and methacrylamide; olefin sulfonic acids such as ethylene sulfonic acid, allyl sulfonic acid, and methallylsulfonic acid; vinyl compounds such as alkyl vinyl ethers, dimethyl allyl vinyl ketone, N-vinylpyrrolidone, vinyl chloride, vinyl ethylene carbonate, 2,2-dialkyl-4-vinyl-1,3-dioxane, glycerin monoallyl ether, and 3,4-diacetoxy-1-butene; vinylidene chloride, 1,4-diacetoxy-2-butene, vinylene carbonate, polyoxypropylene, and polyoxypropylene vinylamine. From the viewpoint of gas barrier properties, the unsaturated monomer is preferably an olefin, and more preferably ethylene.

[0057] Examples of the polymerization catalyst include radical polymerization catalysts such as azobisisobutyronitrile, benzoyl peroxide, lauryl peroxide, etc. The polymerization method is not particularly limited, and bulk polymerization, emulsion polymerization, solvent polymerization, etc. can be used.

[0058] The degree of polymerization of PVA is preferably 300 to 3000. If the degree of polymerization is less than 300, the barrier properties tend to decrease, while if it exceeds 3000, the viscosity becomes too high and the coating suitability tends to decrease. The saponification degree of PVA is preferably 80 mol% or more, more preferably 90 mol% or more, and even more preferably 98 mol% or more. The saponification degree of PVA may be 100 mol% or less, or may be 99.9 mol% or less. The polymerization degree and saponification degree of PVA can be measured in accordance with the method described in JIS K 6726 (1994).

[0059] EVOH is generally obtained by saponifying a copolymer of ethylene and an acid vinyl ester such as vinyl acetate, vinyl formate, vinyl propionate, vinyl valerate, vinyl caprate, vinyl laurate, vinyl stearate, vinyl pivalate, or vinyl versatate.

[0060] The ethylene unit content of EVOH is 10 mol% or more, more preferably 15 mol% or more, even more preferably 20 mol% or more, and particularly preferably more than 35 mol%. The ethylene unit content of EVOH is preferably 65 mol% or less, more preferably 55 mol% or less, and even more preferably less than 50 mol%. When the ethylene unit content is 10 mol% or more, the gas barrier properties or dimensional stability can be maintained well under high humidity. On the other hand, when the ethylene unit content is 65 mol% or less, the gas barrier properties can be improved. The ethylene unit content of EVOH can be determined by NMR.

[0061] The saponification can be carried out using an alkali or an acid, but from the viewpoint of the saponification rate, an alkali can be used. Examples of the alkali include alkali metal oxides such as sodium hydroxide and potassium hydroxide, and alkali metal alkoxides such as sodium ethylate, potassium ethylate, and lithium methylate.

[0062] The thickness of the resin layer 21 is not particularly limited, but from the viewpoint of barrier properties and processability, it is preferably 0.05 to 5 μm, and more preferably 0.1 to 2 μm.

[0063] The mass per unit area of ​​the resin layer 21 is 0.1 to 10 g / m 2 This mass can be set to 0.1 g / m 2 If the mass is 10 g / m or more, the surface of the resin layer 21 can be formed to be sufficiently smooth even if the surface smoothness of the base layer 20 is insufficient, and therefore defects in the inorganic thin film layer 22 laminated on the surface of the resin layer 21 can be reduced. 2 If the above ratio is less than 1, it is advantageous in terms of realizing a mono-material packaging material and reducing material costs.

[0064] The arithmetic mean height Sa of the surface of the resin layer 21 can be, for example, 0.2 μm or less, and more preferably 0.01 to 0.1 μm or 0.02 to 0.1 μm. When the arithmetic mean height Sa of the surface of the resin layer 21 is 0.2 μm or less, the inorganic thin film layer 22 can be formed with excellent gas barrier properties. On the other hand, when the arithmetic mean height Sa of the surface of the resin layer 21 is 0.01 μm or more, the adhesion between the resin layer 21 and the inorganic thin film layer 22 can be improved due to the anchor effect compared to when the arithmetic mean height Sa is less than 0.01 μm.

[0065] When a propylene monopolymer film (monopolymer layer) is used as the base layer 20, the propylene monopolymer film has excellent heat resistance, but has the drawback that its surface is prone to developing vein patterns. For this reason, sufficient barrier properties cannot be achieved even when the inorganic thin film layer 22 is formed directly on the surface of the base layer 20. Therefore, by interposing the resin layer 21 between the propylene monopolymer film and the inorganic thin film layer 22, excellent gas barrier properties can be achieved.

[0066] From the viewpoint of achieving excellent oxygen barrier properties, the surface of the resin layer 21 preferably has a logarithmic attenuation at 100°C of, for example, 0.20 or less and a logarithmic attenuation at 125°C of, for example, 0.30 or less, as measured using a rigid pendulum physical property tester. This logarithmic attenuation can be measured using the rigid pendulum method (A&D Corporation's RPT-3000W rigid pendulum physical property tester). Using an RBP-020 pipe edge, the measurement is performed by heating from 30°C to 130°C at a heating rate of 10°C / min. Measurements are performed at three locations under these conditions, and the average values ​​of the logarithmic attenuation at 100°C and 125°C are calculated. A small logarithmic attenuation means that the resin molecules that make up the surface of the object being measured are less likely to move when exposed to heat.

[0067] The inorganic thin film layer 22 is a layer made of an inorganic compound containing Si or Al (atoms). Examples of inorganic compounds include metal oxides such as silicon oxide (SiOx) and aluminum oxide (AlOx), metallic aluminum (Al), silicon nitride (SiN), and silicon oxynitride (SiON). From the viewpoints of transparency and barrier properties, the inorganic compound constituting the inorganic thin film layer 22 is preferably aluminum oxide or silicon oxide. Furthermore, from the viewpoint of excellent tensile stretchability during processing, the inorganic compound constituting the inorganic thin film layer 22 is preferably silicon oxide. By using the inorganic thin film layer 22, it is possible to obtain high barrier properties while suppressing the overall thickness of the gas barrier laminate 19.

[0068] The inorganic thin film layer 22 can have a thickness of 5 to 80 nm. A thickness of 5 nm or more can provide sufficient gas barrier properties. A thickness of 80 nm or less can prevent cracks from occurring due to deformation caused by internal stress in the thin film, thereby preventing a decrease in gas barrier properties. A thickness exceeding 80 nm is undesirable from an economic standpoint, as it increases the cost due to an increase in the amount of material used and a longer film formation time. From the above standpoint, the thickness of the inorganic thin film layer 22 is more preferably 10 to 50 nm, and even more preferably 20 to 40 nm.

[0069] The resin layer having vinyl alcohol units (hereinafter simply referred to as "resin layer") 23 is a layer containing polyvinyl alcohol (PVA) or ethylene-vinyl alcohol copolymer (EVOH) as a main component, similar to the resin layer 21. From the viewpoints of heat resistance and gas barrier properties, EVOH can be preferably used.

[0070] The resin layer 23 may contain a silane compound. Examples of the silane compound include tetraalkoxysilanes such as tetramethoxysilane and tetraethoxysilane, reactive group-containing trialkoxysilanes such as glycidoxypropyltrimethoxysilane and acryloxypropyltrimethoxysilane, and silazanes such as hexamethyldisilazane. Examples of the silane compound include compounds generally used as silane coupling agents and polysiloxane compounds having siloxane bonds. Examples of the silane compound include vinyltrimethysilane and vinyltrimethysilane. It is preferable to use a silane coupling agent such as oxysilane, γ-chloropropylmethyldimethoxysilane, γ-chloropropyltrimethoxysilane, glycidoxypropyltrimethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropylmethyldimethoxysilane, or 1,3,5-tris(3-trimethoxysilylpropyl)isocyanurate.

[0071] The mass ratio of the silane compound to the mass of the resin layer 23 can be set to 0.005 to 0.80 from the viewpoint of maintaining adhesion to the inorganic thin film layer 22 and gas barrier properties.

[0072] The thickness of the resin layer 23 is not particularly limited, but from the viewpoint of barrier properties and processability, it is preferably 0.05 to 2 μm, and more preferably 0.1 to 0.6 μm.

[0073] The gas barrier laminate 19 can be manufactured, for example, by a manufacturing method including the steps of forming a resin layer 21 on a base layer 20, forming an inorganic thin film layer on the resin layer 21, and forming a resin layer 23 on the inorganic thin film layer 22.

[0074] The resin layer 21 can be formed by applying a coating liquid containing PVOH or EVOH and a solvent to the base layer 20. As the solvent, water, dimethyl sulfoxide, dimethylformamide, dimethylacetamide, N-methylpyrrolidone, various glycols, polyhydric alcohols such as trimethylolpropane, amines such as ethylenediamine and diethylenetriamine, etc. can be used alone or in combination of two or more. From the viewpoint of reducing the environmental load, it is preferable to use water as the solvent.

[0075] The coating liquid can be applied to the substrate layer by any appropriate method. The coating liquid can be applied by a wet film-forming method using, for example, a gravure coater, a dip coater, a reverse coater, a wire bar coater, or a die coater. The application temperature and drying temperature of the coating liquid are not particularly limited and can be, for example, 50°C or higher.

[0076] The resin layer 21 may be formed on the base layer 20 by an extrusion method. In the case of the extrusion method, multi-layer extrusion using a T-die may be employed. An example of an adhesive that can be used during extrusion is maleic anhydride-modified polypropylene resin. This adhesive may be applied to the base layer 20 and then dried to form an adhesive layer on the base layer 20 in advance. From the viewpoints of adhesion, followability, processability, etc., the thickness of the adhesive layer may be 0.1 to 50 μm, and preferably 0.5 to 20 μm.

[0077] The inorganic thin film layer 22 can be formed by, for example, vacuum deposition. Vacuum deposition can be performed using physical vapor deposition or chemical vapor deposition. Examples of physical vapor deposition include, but are not limited to, vacuum deposition, sputtering, and ion plating. Examples of chemical vapor deposition include, but are not limited to, thermal CVD, plasma CVD, and photo CVD.

[0078] In the vacuum film formation, resistance heating vacuum deposition, EB (Electron Beam) heating vacuum deposition, induction heating vacuum deposition, sputtering, reactive sputtering, dual magnetron sputtering, plasma enhanced chemical vapor deposition (PECVD), and the like are particularly preferably used. However, in terms of productivity, vacuum deposition is currently the most superior. As a heating means for vacuum deposition, it is preferable to use any of the electron beam heating method, resistance heating method, and induction heating method.

[0079] The resin layer 23 can be formed by the coating method or the extrusion method, similar to the process for forming the resin layer 21.

[0080] When the resin layer 23 is formed by a coating method, the coating liquid is The coating solution may contain a silane compound. When the coating solution contains a silane compound, the coating solution may further contain an acid catalyst, an alkali catalyst, a photopolymerization initiator, or the like.

[0081] Furthermore, the film or sheet constituting the body of the tube container according to the present invention may have the following layer structure.

[0082] 14 and 15 are cross-sectional views showing examples of layer configurations of materials that can be used for the body portion of a tube container according to a modified example.

[0083] The material 41 shown in Fig. 14 is obtained by laminating, in this order, an adhesive layer 44, a polypropylene layer 45 having barrier properties, an adhesive layer 46, and an unstretched polypropylene layer 47 on an unstretched polypropylene layer 43. The adhesive layers 44 and 46 are formed, for example, from an adhesive for dry lamination. The polypropylene layer 45 having barrier properties can be formed, for example, from the gas barrier laminate 19 shown in Fig. 13.

[0084] 15 shows a material 42 in which an adhesive resin layer 48, a barrier polypropylene layer 45, an adhesive resin layer 49, and an unstretched polypropylene layer 47 are laminated in this order on an unstretched polypropylene layer 43. The adhesive resin layers 48 and 49 can be formed, for example, from a mixture of polypropylene and modified polypropylene. Modified polypropylene is a compound that exhibits adhesive properties by graft-modifying polypropylene with an organic acid such as maleic anhydride.

[0085] Material 41 shown in Fig. 14 and material 42 shown in Fig. 15 are both made of a resin mainly composed of polypropylene. Therefore, by welding a body made of material 41 or 42 to a spout made mainly of resin, a tube container can be constructed in which 90% by mass or more of the combined body and spout is polypropylene. Therefore, a tube container with excellent recyclability can also be realized by using the film or sheet materials shown in Figs. 14 and 15.

[0086] 14 and 15 may be configured as a thin film with a total thickness of 250 μm or less, or as a sheet material with a thickness of about 300 to 500 μm that can be used for laminated tubes. By forming the body of a laminated tube using a sheet material with the layer structure shown in FIG. 14 or 15 and welding it to an outlet part made of a resin mainly composed of polypropylene, it is possible to form a highly recyclable laminated tube containing polypropylene in a total of 90 mass % or more of the body and outlet part. [Example]

[0087] Examples of specific implementations of the present invention will be described below. Example 1 A 20 μm-thick stretched polypropylene film (Futamura Chemical Co., Ltd., FOA) and an 80 μm-thick unstretched polypropylene film (Futamura Chemical Co., Ltd., FHK2) were dry-laminated using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a tube with a diameter of 35 mm. The spout was formed by injection molding polypropylene. After welding the resulting tube to the spout, water was poured into the body and one end of the body was sealed to produce the tube container shown in Figure 1.

[0088] Example 2 A barrier coating agent containing montmorillonite and PVA was applied to a 20 μm-thick stretched polypropylene film (Futamura Chemical Co., Ltd., FOA) to obtain a barrier stretched polypropylene film. The resulting barrier stretched polypropylene film and an 80 μm-thick unstretched polypropylene film (Futamura Chemical Co., Ltd., FHK2) were dry-laminated using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a tube with a diameter of 35 mm. The spout was formed by injection molding a barrier resin containing polypropylene and 10% EVOH by total mass. The resulting tube was welded to the spout, and then water was poured into the body, and one end of the body was sealed to produce the tube container shown in Figure 1.

[0089] Example 3 A 20 μm-thick stretched polypropylene film (Futamura Chemical Co., Ltd., FOA), a 20 μm-thick aluminum-coated stretched polypropylene film (Mitsui Chemicals Tohcello, Inc., OP102), and a 60 μm-thick unstretched polypropylene film (Futamura Chemical Co., Ltd., FHK2) were dry-laminated together using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a 35 mm diameter tube. The spout was formed by injection molding a barrier resin containing polypropylene and 10% EVOH by weight. The resulting tube was welded to the spout, and water was poured into the body, closing one end of the body, to produce the tube container shown in Figure 1.

[0090] (Comparative Example 1) A 12 μm-thick silica-deposited polyester film (GL-RD, manufactured by Toppan Printing Co., Ltd.) and a 100 μm-thick unstretched polypropylene film (FHK2, manufactured by Futamura Chemical Co., Ltd.) were dry-laminated together in this order using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a tube with a diameter of 35 mm. The spout was formed by injection molding a barrier resin made of polypropylene with 10% EVOH added by total mass. The resulting tube was welded to the spout, and then water was poured into the body, and one end of the body was sealed to produce the tube container shown in Figure 1.

[0091] (Comparative Example 2) A 12 μm-thick silica-deposited polyester film (GL-RD, manufactured by Toppan Printing Co., Ltd.), a 12 μm-thick oriented polypropylene film (P60, manufactured by Toray Industries, Inc.), and an 80 μm-thick unoriented polypropylene film (FHK2, manufactured by Futamura Chemical Co., Ltd.) were dry-laminated together using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a 35 mm diameter tube. The spout was formed by injection molding a barrier resin containing polypropylene and 10% EVOH by weight. The resulting tube was welded to the spout, and water was poured into the body, closing one end of the body, to produce the tube container shown in Figure 1.

[0092] (Comparative Example 3) A 12 μm thick silica-deposited polyester film (GL-RD, manufactured by Toppan Printing Co., Ltd.), a 15 μm thick stretched nylon film (ONBC, manufactured by Unitika Ltd.), and a 60 μm thick unstretched polyethylene film (SE620L, manufactured by Tamapoly Co., Ltd.) were dry-laminated together in this order using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a tube with a diameter of 35 mm. The spout was made of polypropylene with 10% EVOH added to the total mass. The tube was welded to the outlet, and then water was poured into the body, and one end of the body was closed to produce the tube container shown in Figure 1.

[0093] Comparative Example 4 A 50 μm-thick uniaxially oriented polyethylene film (PE3K-BT, manufactured by Futamura Chemical Co., Ltd.), a 12 μm-thick oriented polyester film (P60, manufactured by Toray Industries, Inc.), and an 80 μm-thick unoriented polyethylene film (SE620L, manufactured by Tamapoly Co., Ltd.) were dry-laminated together using a two-component curing urethane adhesive to produce a film for forming the body. The resulting film was processed into a cylindrical shape using a bag-making machine to form a tube with a diameter of 35 mm. The spout was formed by injection molding polypropylene. The resulting tube was welded to the spout, and water was poured into the body, closing one end of the body, to produce the tube container shown in Figure 1.

[0094] (Comparative Example 5) A barrier tube with a thickness of 100 μm and a diameter of 35 mm was fabricated by extrusion molding. The layer structure was polypropylene (42 μm) / adhesive resin layer (3 μm) / EVOH (10 μm) / adhesive resin layer (3 μm) / polypropylene (42 μm). The outlet was formed by injection molding polypropylene. The resulting tube was welded to the outlet, and then water was poured into the body, and one end of the body was closed to produce the tube container shown in Figure 1.

[0095] The loop stiffness of the films produced in each Example and Comparative Example and the stiffness of the tube container filled with water were evaluated as follows.

[0096] (Loop Stiffness) The films or tubes produced in each example and comparative example were cut into rectangular shapes of 15 mm x 60 mm to prepare measurement samples, which were then set in a loop shape in a Loop Stiffness Tester (registered trademark, Toyo Seiki Seisakusho, Ltd.) to measure the loop stiffness.

[0097] (Firmness) The tube containers filled with water produced in each Example and Comparative Example were subjected to a sensory evaluation of their firmness when touched with the hand, and were classified into one of the following categories: ◎: very firm, ○: firm, △: some firmness but insufficient, ×: container is soft and difficult to handle.

[0098] Table 1 shows the layer structure, total thickness, loop stiffness (LS) value, stiffness, and whether or not gravure printing is possible for each example and comparative example. [Table 1]

[0099] As shown in Table 1, in Examples 1 to 3, the films constituting the body portion had loop stiffness desirable for tube containers, and sufficient stiffness was obtained when tube containers were produced using these films. Furthermore, the films according to Examples 1 to 3 are also suitable for gravure printing, making it possible to apply attractive printing to the body portion of the tube container.

[0100] In contrast, in Comparative Examples 1, 4, and 5, the loop stiffness of the film constituting the body itself was insufficient, and the tube containers produced using this film were soft and lacked stiffness. Furthermore, in Comparative Examples 2 and 3, the loop stiffness of the film constituting the body was a desirable value for a tube container, but although the tube containers produced using this film had some stiffness, they were not easy to handle. Furthermore, in Comparative Example 5, the body was made of an extruded tube, which was not suitable for gravure printing, making it unsuitable for decorative printing. [Industrial Applicability]

[0101] The tube container according to the present invention can be used as a packaging material for medicines, cosmetics, food, etc. [Explanation of symbols]

[0102] 1. Torso 2 Spout part 3 Dispensing tube part 4 Flange 5a, 5b ends 6a, 6b end 15 layers (unstretched polypropylene) 16th and 17th layers (oriented polypropylene)

Claims

1. a tubular body portion having one end closed; a spout attached to the other end of the body, The body and the spout contain polypropylene in a total amount of 90% by mass or more, The film constituting the body portion is At least one layer of oriented polypropylene, A layer of unstretched polypropylene is provided on only one of the two surfaces of the film, The loop stiffness is 120 to 200 mN / 15 mm; the body portion is a molded body obtained by molding the film into a cylindrical shape having a pair of parallel edges, The inner surfaces of the band-shaped portions including each of the pair of edges are joined together.

2. The tube container according to claim 1 , wherein the spout portion is made of a resin material containing polypropylene as a main component.

3. The tube container according to claim 2 , wherein a barrier layer having barrier properties is laminated on the layer of oriented polypropylene.

4. The pouring outlet portion is A cylindrical pouring tube portion; a flat flange portion connected to one end of the cylindrical pouring portion and extending outward from the cylindrical pouring portion in a direction perpendicular to the axial direction of the cylindrical pouring portion; 4. The tube container according to claim 1, wherein the inner surface of the other end of the body portion is joined to one of the two surfaces of the flange portion on the other end side of the cylindrical pouring portion.

Images