JPH0776355A - Tube container - Google Patents

Abstract

PURPOSE:To provide a high quality tube container which does not lower the quality of contents, is excellent in smell barrier for the contents, not liable go get delaminated even though a sheet laminated, for instance, with metal foil is used for forming the trunk of the tube container, and is practically sufficient in strength for bonding its shoulder to the trunk. CONSTITUTION:In a tube container which is composed of a tubular container trunk part made up of a laminated sheet with its lower end closed, a shoulder part connecting to the upper end of the tubular container trunk part, a mouth- and-neck part connecting to the shoulder part, and a cap that can be attached to and detached from the mouth-and-neck part, resin for the shoulder part is made of polyester, for which DELTAH for crystallization peak (Tc) is 15J/g or more, and the innermost layer of the trunk part is made of polyester resin, and the shoulder part and the innermost layer of the trunk part are bonded together by heating.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a tube container.
More specifically, it is particularly suitable for filling a paste-like material in which foods, pharmaceuticals, dyes, etc. containing aroma components, vegetable oils, etc. are filled, quality retention of contents, barrier property of aroma components, tube container The adhesive layer of the laminated film forming the body is attacked by the filling contents, and the adhesive strength is reduced,
The present invention relates to a tube container which is excellent in preventing so-called delamination in which a laminated film peels off.

[0002]

2. Description of the Related Art A tube container filled with a fluid-semi-fluid filling material represented by a pasty material is a tubular container body whose lower end is closed. A shoulder portion that is continuous to the upper end of the tubular container body, a mouth and neck portion that is continuous to the shoulder portion, and a cap that is detachably engaged with the mouth and neck portion. In particular, in the case of a tube container in which an anaerobic filler is filled, it is required that the container has excellent properties with respect to gas barrier properties, such as a metal container body, A tube container or the like having a container body made of a laminated sheet of a polyolefin resin layer and a metal foil is used. By the way, in the tube container having the conventional metal container body, although excellent gas barrier properties are obtained due to the characteristics of the material of the container body, depending on the kind of the filling material filled in the container. The metal that is the material of the container body is corroded, which causes pinholes in the container body, and the inner filler is pushed out by squeezing out. Due to the structure of the tube container, it is formed of an extremely thin metal foil. Therefore, the mechanical properties of the container body are poor, and there is a drawback that the container body is likely to be broken, for example, at the time of filling the filling material or handling the tube container by the consumer. There is. Further, in a container having a container body made of a laminated sheet of a polyolefin resin layer and a metal foil, the resin layer is, for example, 80% from the relationship that the polyolefin resin layer which is the inner surface layer of the container body has heat sealing properties. Since it has a thickness of up to 100 μm or more, it has a problem in quality retention characteristics due to absorption of a flavoring component or an effective component in the inner filler. Furthermore, when using a sheet laminated with a metal foil with a polyolefin resin as the innermost layer for the tube body, not only is there a problem in maintaining the quality of the filler in the tube container as described above, but also the adhesiveness of aroma components. This is a problem because delamination occurs due to its large penetration into the surface. Further, in the shoulder portion of the tube container, the shoulder portion made of the polyolefin resin absorbs and permeates the scent component and the effective component contained in the inner filler, which causes a problem in quality retention characteristics. For this,
A method of inserting an inner shoulder made of a polyester resin having excellent barrier properties into the inside of the shoulder made of a polyolefin resin, and using a shoulder having excellent barrier properties, for example, a laminate of ethylene-vinyl alcohol copolymer, etc. is proposed. Has been done. However, the barrier property of the shoulder portion of the tube container by these methods has a practical problem that the tube container manufacturing process or processing method becomes complicated. In recent years, polyester resin materials having excellent barrier properties, particularly polybutylene terephthalate resins having excellent crystallinity, have been attracting attention for these problems. However, when a polyester resin is used for the shoulder portion of the tube container, there is a drawback that the adhesive strength with the polyolefin resin forming the innermost layer of the tube body is insufficient, and it is not practically used at present.

[0003]

According to the present invention, the tube container shoulder and the innermost layer of the body are formed of a polyester resin, and in particular, a paste-like material containing a fragrance or vegetable oil or a toothpaste is filled inside. Even if it is used, the quality characteristics of the inner filler are not deteriorated and the odor barrier property of the inner filler is excellent.For example, even when a sheet laminated with a metal foil is used for the body of the tube container, delamination may occur. The present invention provides a good-quality tube container in which the adhesive strength between the shoulder part and the body part of the tube container is practically sufficient. That is, the present invention is a tubular container body composed of a laminated sheet, the lower end portion of which is closed, a shoulder portion continuous to the upper end portion of the tubular container body portion, and a continuous shoulder portion. In a tube container comprising a mouth and a neck that is engaged and a cap that is detachably engaged with the mouth and neck, the shoulder resin is made of a polyester resin having a crystallization peak (Tc) ΔH of 15 J / g or more. The innermost layer of the body is made of polyester resin, and the shoulder and the innermost layer of the body are heat-bonded to each other.

The structure of the present invention will be described in detail below. In the present invention, a polyester resin having a crystallization peak (Tc) ΔH of 15 J / g or more is used as the shoulder resin forming the tube container. Here, if the crystallization peak (Tc) ΔH is less than 15 J / g, the aroma components contained in the inner filler to be filled in the tube container are adsorbed by the shoulder polyester resin, and the shoulder part outside the container. Permeates into. The ΔH of the crystallization peak of the shoulder polyester resin used in the present invention is preferably 15 J / g or more, more preferably 20 J / g or more. Further, the innermost layer of the body forming the tube container of the present invention is made of polyester resin. The innermost layer of the body of the tube container made of the polyolefin resin has insufficient thermal adhesion to the shoulder of the tube container made of the crystalline polyester, and cannot be put to practical use.

The present inventors have come to use a polyester resin for the innermost layer of the body of the tube container from the viewpoint of thermal adhesiveness with the crystalline polyester forming the shoulder part of the tube container. The polyester resin that can be used in the body of the tube container in the present invention is preferably a polyethylene terephthalate-based polymer or a polybutylene terephthalate-based polymer, and may be a copolymer. Furthermore,
From the viewpoint of adhesive strength due to heat adhesion with the tube container shoulder,
From the molten state using a differential scanning calorimeter (DSC)
It is preferable that the height of the crystallization peak (exothermic peak) when cooled at a temperature decrease rate of 0 to 15 mW is in the range. Further, the tube container body that can be used in the present invention may be one that is extruded into a cylindrical shape and cut to a predetermined size, or a sheet-shaped one that is rounded into a cylindrical shape and the end portions are heat-welded. . When using a sheet-shaped material that is rolled into a cylindrical shape and heat-sealed at the ends, a sheet laminated with metal foil or the like is also used as the outermost layer in the tube container body to form a cylindrical body. Needless to say, it is preferable to use a polyester resin.

Next, regarding the thermal bonding of the shoulder portion and the body portion constituting the tube container of the present invention, the resin temperature of the shoulder portion of the tube container at the time of thermal bonding is a polyester type resin forming the innermost layer of the tube container. It suffices to perform thermal bonding at a temperature higher than the melting point and softening point of the resin, but from the viewpoint of the adhesive strength with the body, it is preferable to perform thermal bonding at a temperature 20 ° C. or more higher than those. The polyester resin forming the shoulder portion of the tube container may be in a molten state or a semi-molten state at the time of heat bonding, and the resin temperature of the shoulder portion of the tube container at the time of the heat bonding is important. From this point of view, what is preferable as the polyester resin used for the shoulder portion of the tube container of the present invention is that the acid component constituting the polyester is mainly a terephthalic acid residue and the diol component is mainly a 1,4-butanediol residue and / or ethylene. It is a polyester resin that is a glycol residue. If the crystallization peak satisfies the above range, a copolymer polyester can be used.
As the acid component of the copolymerization components, succinic acid, glutaric acid, adipic acid, pimelic acid, azelaic acid, sebacic acid, dodecane diacid, brassic acid, saturated aliphatic dicarboxylic acids exemplified by dimer acid, phthalic acid, Isophthalic acid,
Aromatic dicarboxylic acids typified by 2,6-naphthalenedicarboxylic acid, and trimesic acid, trimellitic acid and the like can be used as the branching component. These copolymerization components may be used alone or in any combination as required. Further, as the diol component among the copolymerization components, ethylene glycol,
1,3-propanediol, 1,4-butanediol, 1,3
-Butanediol, 1,5-pentanediol, neopentyl glycol, 1,6-hexanediol, 1,7-heptanediol, 1,10-decanediol, cyclohexanediol, cyclohexanedimethanol, etc. Alicyclic diols or polyglycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, polytetramethylene glycol, etc. or aromatic diols exemplified by bisphenol A, ethoxylated bisphenol A ethoxylated bisphenol S, etc. as a branching component You may use pentaerythritol etc. A component having a hydroxyl group and a carboxylic acid group in one molecule, represented by 4-hydroxybenzoic acid, may be used as a copolymerization component as long as the performance of the polyester resin is not significantly changed. or,
Even for polyesters and / or copolymers which do not fall within the range of the crystallization peak, those containing a compound having a nucleating action such as boron nitride and calcium carbonate fall within the range of the crystallization peak. If so, the polyester composition can be used for the shoulder portion of the tube container of the present invention.

The polyester resin used in the present invention is not limited by the production method thereof, and may be a so-called direct polycondensation method in which an acid component and a diol component are esterified by a dehydration reaction and then condensed. The dicarboxylic acid portion of the acid component monomer may be obtained by a transesterification method using an esterified product such as methyl ester, ethyl ester, butyl ester and the diol component as starting materials. Further, another thermoplastic resin can be blended within a range that does not significantly change the performance of the polyester resin forming the shoulder portion of the tube container of the present invention. Examples of the thermoplastic resin that can be used supplementarily include aromatic polyester resins other than the main polyester resin, nylon 6, nylon 6-6, nylon 6-
Polyamide resin such as 10, nylon 6-12 and nylon 4-6, polyolefin resin mainly containing ethylene, propylene, butene, polystyrene, polystyrene-acrylonitrile, styrene resin such as ABS, polycarbonate, polyphenylene oxide, poly Examples thereof include alkylene acrylate, polyacetal, polysulfone, polyether sulfone, polyetherimide, polyether ketone, and fluororesin. Further, these thermoplastic resins may be used as a mixture of two or more kinds. Further, in addition to the polyester resin constituting the shoulder portion of the tube container of the present invention, if necessary, for example, glass fiber, glass beads, titanium oxide, calcium carbonate,
Well-known fillers such as talc, conventionally well-known substances, that is, lubricants, stabilizers, antistatic agents, pigments and the like may be appropriately blended within a range that does not impair the intended performance of the shoulder portion of the tube container. Further, the shoulder portion of the tube container of the present invention may be made of only the polyester resin and / or the composition, but the polyester resin and / or the composition may have other resin, such as ethylene-vinyl alcohol copolymer and vinylidene chloride. It may be a laminate of barrier resin, polyolefin resin such as polyethylene and polypropylene,
It is important that the thermal bond between the shoulder of the tube container and the body is polyester.

Next, the polyester resin forming the innermost layer of the tube container body of the present invention will be described. Preferred as the polyester-based resin used in the innermost layer of the tubular container body of the present invention, the acid component constituting the polyester is mainly a terephthalic acid residue, and the diol component is mainly a 1,4-butanediol residue and / or ethylene. Polyester which is a glycol residue and its copolymer. Alternatively, it is a polyester copolymer and / or polyester resin composition in which an amorphous resin is blended with a polyester resin. The polyester and / or polyester resin composition preferably used for the innermost layer of the body of the tube container of the present invention means a crystal when cooled from a molten state at a temperature lowering rate of 10 ° C./min using a differential scanning calorimeter (DSC). The height of the chemical conversion peak (exothermic peak) is 0 to 15 mW. Further, it is preferably in the range of 0 to 10 mW from the viewpoint of thermal adhesive strength with the shoulder of the tube container. Further, when a sheet-shaped material having a cylindrically rounded end and heat-welded is used, in order to form a cylindrical tube, a method of heat-sealing the innermost layer and the outermost layer of the sheet, high-frequency sealing Since the method is generally used, it is preferable from the viewpoint of sealing strength of the body of the tube container.

Specific preferred polyesters include, as a copolymer, succinic acid, glutaric acid, adipic acid, as a copolymerizing monomer of the acid component forming the polyester.
Pimelic acid, azelaic acid, sebacic acid, dodecane 2
Acid, brassylic acid, saturated aliphatic dicarboxylic acid exemplified by dimer acid, phthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and as the branching component, trimesic acid, trimellitic acid, etc. can be used. . These copolymerization components may be used alone or in any combination as required.
Among the copolymerization components, the diol components include ethylene glycol, 1,3-propanediol, 1,4-butanediol, 1,3-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6 -Hexanediol, 1,7-heptanediol, 1,10-decanediol,
Aliphatic / alicyclic diols such as cyclohexanediol and cyclohexanedimethanol, or polyglycols such as diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol and polytetramethylene glycol, or bisphenol A, ethoxylated bisphenol A, An aromatic diol exemplified by ethoxylated bisphenol S and pentaerythritol as a branching component may be used. In addition, if the performance of the polyester resin is not significantly changed,
A component having a hydroxyl group and a carboxylic acid group in one molecule represented by 4-hydroxybenzoic acid may be used as a copolymerization component. Further, a polyester resin composition containing another known polymer may be used within a range that does not significantly impair the performance of the tube container body of the present invention. Further, as the polyester resin and / or its composition forming the innermost layer of the body of the tube container of the present invention, a known slip agent, a known additive such as an antistatic agent and the like are required in forming a film. You may use the thing added in the range which does not change largely.

By the way, the innermost layer of the body of the tube container is preferably laminated with a film having another excellent barrier property from the viewpoint of the barrier property of the components contained in the content. Specifically, a highly crystalline polyester resin having a crystallization peak (Tc) ΔH of 15 J / g is preferably laminated on the outer layer of the polyester resin layer. Furthermore, co-extruding the highly crystalline polyester into the innermost layer of the tube container body of the present invention and its adjacent layer reduces the number of steps such as dry lamination without using an adhesive layer, but the aroma of the contents. It is preferable because the barrier properties of the components can be sufficiently maintained. Furthermore, in the case of a tube container body in which a metal foil is laminated, the aroma component contained in the container filling material adheres between the metal foil layer and the innermost resin layer. It is extremely useful for preventing the delamination phenomenon that occurs due to accumulation and attack in the layer.
Other resin layers that can be laminated include polyethylene resin such as low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ionomer, and ethylene-acrylic acid copolymer, and polypropylene resin. The exemplified polyolefin resin, polyvinylidene chloride resin, ethylene-vinyl alcohol copolymer high barrier resin, nylon resin such as nylon 6, nylon 6, and 6 nylon 12 can be used. When another resin layer is laminated on the body of the tube container of the present invention, one type or two or more types of the resin layer may be used, and the point is to be selected according to the characteristics required for the tube container. .

[0011]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto. [Production of Polyester Resin] After changing the compositions of the acid component and the diol component as shown in Tables 1 and 2, the reaction starting materials were charged into a reactor equipped with a stirrer and a distilling tube, and after nitrogen substitution was sufficiently performed. The temperature was raised to 140 ° C. under normal pressure and stirring was started. Further, the temperature was gradually raised to distill off by-product methanol. When the temperature reached 210 ° C, the reactor was gradually depressurized and the temperature was kept constant at 250 ° C with 0.1 torr.
Continue stirring at the pressure of r to reach the desired viscosity, then extrude in strands from the bottom of the reactor, cool with cooling water, cut into a predetermined size with a cutter, and prepare polyester resin pellets did. Examples 1 to 7 and Comparative Examples 1 to 6 Using the polyester resin pellets or polyethylene prepared as described above, tube containers were manufactured and evaluated as follows. The results are shown in Table 3. [Preparation of sheet for tube container body] Extruder 1 (30mm
φ, L / D = 28) hopper is charged with the resin raw material forming the innermost layer of the body shown in Table 2, and extruder 2 (40 mmφ, L / D = 2
Polybutylene terephthalate (manufactured by Polyplastics Co., Ltd., Duranex 600FP) was put into the hopper of 8) and extruded into a film form by a multi-manifold die to obtain a film of 20 μm in each layer and a total of 40 μm. Adcoat AD-502 manufactured by Toyo Morton Co., Ltd. on the polyethylene surface of the original fabric consisting of polyethylene / aluminum foil / polyethylene
The 1 to 2 g / m ² was applied, it was laminated to polybutylene terephthalate surface of the co-extruded polyester film. Similarly, lamination was performed on the polyethylene on the opposite side so that the polybutylene terephthalate surface came to obtain a raw material for body. [Molding of Tube Container] The resin raw materials shown in Table 1 for forming the tube container were charged into a shoulder discharge extruder hopper, and the molten resin was discharged into the shoulder mold at a temperature shown in Table 3. Then, the body part, which was previously sealed in a cylindrical high frequency shape, was pressed against the discharged molten resin in the shoulder mold and heat-bonded to obtain a tube container in which the contents were not filled and evaluated. The evaluation method is as follows. <Adhesive strength> A tube container not filled with the contents was cut from the body to the shoulder in a width of 15 mm, and the adhesive strength between the shoulder and the body was measured at a pulling speed of 300 mm / min. The evaluation was performed in the following four stages. ◎ Over 2.0 kg / 15 mm ○ 1.0 〜 2.0 kg / 15 mm △ 0.5 〜 1.0 kg / 15 mm × less than 0.5 kg / 15 mm It is judged that the adhesive strength less than 0.5 kg / 15 mm is not practically usable. The following aroma retention and delamination were confirmed to be untestable. <Aroma retaining property> A medicinal component (dl-camphor / l-menthol / methyl salicylate /
The absorbent cotton containing d-limonene (1/1/1/1) was put in, the end of the body was heat-sealed, and the body was stored at room temperature for 1 month, and a sensory test for odor leakage was performed. The evaluation was performed in the following three stages. ○ No odor △ Slight odor × Strong odor <Delamination occurred> Whether or not peeling (delamination) has occurred in the film layer inside the barrel by incising the barrel of the tube container that was subjected to the aroma retention test Was visually determined.

[0012]

[Table 1]

[0013]

[Table 2]

[0014]

[Table 3]

Claims (6)

[Claims] 1. A tubular container body formed of a laminated sheet and having a closed lower end, a shoulder portion continuous with an upper end portion of the tubular container body, and a shoulder portion continuous with the shoulder portion. In a tube container consisting of a mouth and neck and a cap that is detachably engaged with the mouth and neck, the shoulder resin is made of a polyester resin having a crystallization peak (Tc) ΔH of 15 J / g or more, A tube container, wherein the innermost layer of the body is made of polyester resin, and the shoulder and the innermost layer of the body are heat-bonded. 2. The height of the Tc peak of the polyester resin forming the innermost layer of the body part (peak obtained when cooled from the molten state at a temperature lowering rate of 10 ° C./min) is 0 to 15 mW. The described tube container. 3. The tube container according to claim 1, wherein the temperature of the shoulder resin at the time of heat bonding is higher than the melting point or softening point of the polyester resin forming the innermost layer of the tube by 20 ° C. or more. 4. A polyester resin forming a shoulder portion is a polybutylene terephthalate resin or a copolymer thereof,
Polyethylene terephthalate resin and its copolymer, or a polyester resin composition obtained by blending these resins with other resins, wherein the polyester resin in the innermost layer of the tube body is a polybutylene terephthalate copolymer, polyethylene terephthalate copolymer, poly The tube container according to any one of claims 1 to 3, which is a polyester resin composition mainly containing butylene terephthalate and / or a copolymer thereof or polyethylene terephthalate and / or a copolymer thereof. 5. The tube body has a crystallization peak (Tc) ΔH of 15 in the outer layer of the innermost polyester resin layer.
The tube container according to any one of claims 1 to 4, comprising a laminated sheet in which a polyester resin having a J / g or more is laminated. 6. The heat-bonding between the shoulder portion forming the tube container and the innermost layer of the body portion is performed at the same time when the shoulder portion is molded.
The tube container according to any one of 1 to 5.