JP3258800B2 - Laminated material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated material, and more particularly to a laminated material used for a tube container which contains a fluid or semi-fluid substance and has excellent storage stability.

[0002]

2. Description of the Related Art A tube container for containing a fluid or semi-fluid substance represented by a paste-like material such as pastes, cosmetics and paste foods has a moderate stiffness, water resistance, gas barrier property and the like. A tubular body formed of a laminated material having physical properties, a closing member having a shoulder and a neck and engaged with an upper opening end of the body, and detachably attached to the neck of the closing member. And an attached cap.

[0003] Such a tube container is required to have a storage property as a tube container, that is, a resistance to delamination with respect to penetration of contained contents.

[0004] From this point, for example, Japanese Patent Application Laid-Open No. Sho 62-6474.
In Japanese Patent Publication No. 0, a tube container having a preserving effect with excellent content resistance has a laminated structure of a low-density polyethylene film / biaxially-stretched film / aluminum foil / medium-high-density polyethylene film. There has been proposed a tube container filled with liquid silicone rubber, which is laminated and laminated with an agent. Further, Japanese Patent Application Laid-Open No. 5-77355 proposes a tube container in which a second intermediate barrier material is formed inside a first barrier material to prevent delamination due to penetration of contents.

[0005] By the way, it is a necessary physical property that the tube container has excellent storage stability and stable pressure resistance as the tube container. As disclosed in, for example, Japanese Patent Application Laid-Open No. 63-55063, a tube container is generally formed by laminating one side edge of a laminated material and the other side and joining the body by heat welding. Formed by Regarding the packaging material strength of the tube container, the adhesive strength at the overlapping portion is the weakest, and is generally expressed as the tensile strength of the overlapping adhesive portion in addition to the pressure resistance strength, and the strength of the interlayer strength is also required. .

[0006]

However, in the above conventional example, when a medium to high density polyethylene film is disposed on the innermost layer side as disclosed in Japanese Patent Application Laid-Open No. 62-64740, for example, hack oil or mineral is added to the tube container. When filling contents containing permeable components such as oils and hydrocarbon waxes, these components penetrate the innermost film, swell and plasticize the adhesive, leading to delamination and bag breakage. There was a defect that was. Further, the container disclosed in JP-A-5-77355 has a problem that the preservation effect is enhanced, but the production cost is increased.

The present invention has been made in view of such circumstances, and an object of the present invention is to provide a low-cost laminated material used for a tube container having high interlayer strength and excellent storage stability of contents. I do.

[0008]

To achieve the above object, the present invention comprises an intermediate support layer made of a biaxially stretched resin film, a barrier layer formed inside the intermediate support layer, and an intermediate support layer. An outermost layer, which is located outside the support layer and is made of a thermoplastic resin layer;
An innermost layer of 92 to 0.95 linear polyethylene resin, and further comprising an acid copolymer layer and a low-density polyethylene resin layer between the innermost layer and the barrier layer in order from the barrier layer side. This is a characteristic laminated material.

The linear polyethylene constituting the innermost layer is as follows:
This is an ethylene-α olefin copolymer, which is a polyethylene having C _{3 to} C ₈ as α olefin and d = 0.92 to 0.95 as density.

[0010] The barrier layer is preferably a metal foil or a metal thin film layer, and aluminum is particularly preferable as the metal.

[0011]

[Function] Barrier layer (soft aluminum foil) and density of 0.
By providing an acid copolymer layer and a low-density polyethylene resin layer in this order from the barrier layer side between the innermost layer composed of 92 to 0.95 linear polyethylene resin layers, the barrier layer and the acid copolymer layer The interlayer strength is increased by the hydrogen bond of the metal-carboxylic acid, thereby stabilizing the adhesion. In addition, by interposing the low-density polyethylene resin layer, the difference in the compatibility and fluidity of the respective resins originally results in the interlayer strength. Stability between the acid copolymer layer having low strength and poor adhesiveness and the innermost layer (linear polyethylene resin) is ensured, and the occurrence of delamination is prevented. Furthermore, when the innermost layer is a linear low-density polyethylene resin layer, high penetration resistance can be obtained even when a content containing a highly permeable component is contained, and content preservation is achieved.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a schematic sectional view of the laminated material of the present invention. In FIG. 1, a laminated material 1 of the present invention includes an intermediate support layer 2 made of a biaxially stretched resin film, a barrier layer 3 formed inside the intermediate support layer (downward in the drawing), and an outside of the intermediate support layer. (Upper part of the drawing) and an outermost layer 4 made of a thermoplastic resin layer, and an innermost layer 4 having a density of 0.9
An innermost layer 5 made of a linear polyethylene resin of 2 to 0.95, and an acid copolymer layer 6 and a low density polyethylene resin layer 7 between the innermost layer 5 and the barrier layer 3 in order from the barrier layer side. And

The intermediate support layer 2 is used to stabilize the dimensions of the tube container. Examples of the biaxially stretched resin film used for the intermediate support layer 2 include polyethylene terephthalate, polypropylene, polyester, nylon, and ethylene-vinyl alcohol copolymer. And a transparent film or a translucent film. The thickness of such a biaxially stretched film is preferably about 10 to 50 μm. Also,
Polyvinylidene chloride or the like may be applied to the surface of the biaxially stretched resin film in order to improve the barrier property by the intermediate support layer 2. Moreover, you may perform printing cosmetic processing by well-known printing methods, such as gravure printing and offset printing.

The barrier layer 3 laminated on the inner side of the intermediate support layer 2 can be preferably formed of a metal foil such as soft aluminum, copper, iron, nickel or the like, but a soft aluminum foil is most preferable. Used for The thickness of the barrier layer 3 is set to 6 in order to obtain a sufficient barrier property.
About 50 μm is preferable.

The outermost layer 4 located outside the intermediate support layer 2
Is made of a thermoplastic resin layer, and as shown in FIG. 2, when the laminated material 1 is formed into a tubular shape to form the body of the tube container,
Since the surface 4a of the outermost layer 4 is superimposed on the surface 5a of the innermost layer (straight-chain polyethylene resin layer) 5 described below at the peripheral portion and heat-sealed, heat sealing is required. , Low density polyethylene, linear polyethylene,
Polypropylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ionomer, polypropylene, ethylene-vinyl alcohol copolymer, polyamide, polyester, It is made of at least one or more thermoplastic resins such as polyacrylonitrile. The thickness of the outermost layer 4 is preferably about 30 to 200 μm.

The outermost layer 4, the intermediate support layer 2, and the barrier layer 3 are laminated and laminated by a known method such as extrusion lamination using low-density polyethylene, dry lamination using a urethane-based adhesive, or the like.

In the present invention, the innermost layer 5 located inside the barrier layer 3 is made of linear polyethylene resin (LLDPE) having a density of 0.92 to 0.95, and is thereby housed in a tube container. Content is, for example, fragrance,
Mineral oil, even when containing a highly permeable substance such as an organic polar solvent, it is possible to suppress the permeability of the content,
The laminate 1 having excellent storage characteristics can be obtained. Further, since the linear low-density polyethylene resin has heat sealing properties, when the laminated material 1 is formed into a cylindrical shape to form the body of the tube container as described above, the surface 5a of the innermost layer 5 is formed. Is superimposed on the surface 4a of the outermost layer 4 at the peripheral portion and is heat-sealed. At this time, heat sealing can be performed reliably and stably. The innermost layer 5 is an ethylene-α-olefin copolymer, and C _{3 is used} as α-olefin.
-C _8, a polyethylene d = .92-0.95 as density, particularly preferably about density from 0.925 to 0.94, it is preferable that the thickness is about 30 to 200 [mu] m.

Between the innermost layer 5 and the barrier layer 3,
In order to stabilize the adhesion between the two, an acid copolymer layer 6 and a low-density polyethylene resin layer 7 are sequentially arranged from the barrier layer side.
Are laminated.

The acid copolymer layer 6 is used to stabilize the adhesion between the barrier layer (aluminum foil) 3 and prevent delamination. For example, ethylene-methacrylic acid copolymer (EMAA), ethylene-methacrylate Acrylic acid copolymer (EA
A) and the like, and in particular, acrylic acid concentration of 4 to 15
% Of ethylene-acrylic acid copolymer is preferred. The interlaminar strength between the acid copolymer layer 6 and the barrier layer (aluminum foil) 3 is increased by the hydrogen bond between the carboxylic acid and the metal, thereby stabilizing the adhesion. The acid copolymer layer 6 is laminated on the barrier layer (aluminum foil) 3 by extrusion lamination, thermal lamination, or the like, and preferably has a thickness of about 10 to 50 μm.

Low density polyethylene resin (LDPE) layer 7
Is used as an intermediate sand polyethylene resin layer for forming the innermost layer 5 made of a linear type polyethylene resin. By interposing the low density polyethylene resin layer 7, the compatibility and fluidity of each resin are originally From the difference, the interlayer strength is weak, the stabilization between the acid copolymer layer 6 and the innermost layer 5 having poor adhesion is secured, and the occurrence of delamination is prevented. The acid copolymer layer 6 and the innermost layer 5 are laminated by extrusion lamination with the low-density polyethylene resin layer 7. The low-density polyethylene resin layer 7 preferably has a density of about 0.91 to 0.93 in order to effectively exhibit the above function,
The thickness is preferably about 10 to 50 μm.

The laminated material 1 according to the present invention obtained as described above is obtained, for example, by punching to obtain a blank plate for forming a tube container body, and then lining the edge of the blank plate with one innermost layer. 5 to the surface 4a of the other outermost layer 4
After being superposed on each other and thermally fused to form a container body, a tube container is obtained through a required process. (Experimental Example) Next, the present invention will be described more specifically with reference to experimental examples. Sample 1 A laminated material having a laminated structure shown in FIG. 1 was prepared as follows.

First, as the outermost layer film, a thickness of 50 μm
Medium-density polyethylene film (manufactured by Dainippon Resin Co., Ltd.)
MPA, density 0.935) with an intermediate support layer of thickness 1
A 2 μm biaxially stretched polyethylene terephthalate film (T4100 manufactured by Toyobo Co., Ltd.) is used as a barrier layer and a 9 μm thick soft aluminum foil (Tokai Aluminum Co., Ltd.)
Are prepared, and each layer is dry-laminated with a urethane-based adhesive (A515 / A12, manufactured by Takeda Pharmaceutical Co., Ltd.) 5 g / m ² (at the time of drying), and a medium density polyethylene film / biaxially stretched polyethylene terephthalate film /
A three-layer laminate of a soft aluminum foil was prepared.

Next, a 30 μm-thick ethylene-methacrylic acid copolymer (EMAA) resin film (manufactured by Mitsui Petrochemical Co., Ltd.) was formed on the soft aluminum foil surface of the laminate.
1108C, an acrylic acid concentration of 11%) was extruded and laminated, and a low-density polyethylene having a thickness of 20 μm (M11P manufactured by Mitsui Petrochemical Co., Ltd., density 0.917) was applied to the ethylene-methacrylic acid copolymer resin surface. Is extruded and laminated to form a 200 μm thick linear polyethylene resin film (SR, manufactured by Dainippon Resin Co., Ltd.).
X, density 0.92) was sand-laminated to obtain a laminated material (sample 1) according to the present invention. Comparative Sample 1 In Sample 1, an ethylene-methacrylic acid copolymer resin film (N1108 manufactured by Mitsui Petrochemical Co., Ltd.) having a thickness of 30 μm was formed on the soft aluminum foil surface of the three-layer laminate.
C, acrylic acid concentration 11%)
Laminate material was prepared in the same manner as in Sample 1, except that a 200 μm-thick linear polyethylene resin film (SRX, manufactured by Dainippon Resin Co., Ltd., density: 0.92) was sand-laminated without interposing a low-density polyethylene film. Comparative sample 1) was obtained. Comparative Sample 2 In Sample 1, a low-density polyethylene resin film having a thickness of 20 μm (Mitsui Petrochemical Co., Ltd.) was formed on the soft aluminum foil surface of the three-layer laminate without interposing an ethylene-methacrylic acid copolymer resin film. ) Made M11P,
By extruding and laminating a density of 0.917),
A laminated material (Comparative Sample 2) was obtained in the same manner as in Sample 1, except that a straight-chain low-density polyethylene resin film (SRX manufactured by Dainippon Resin Co., Ltd., density: 0.92) having a thickness of 200 μm was sand-laminated. Comparative sample 3 In sample 1, a urethane anchor coating agent (Takeda Pharmaceutical Co., Ltd.) was applied to the soft aluminum foil surface of the three-layer laminate.
A310 / A12) to form an anchor coat layer, and a low-density polyethylene resin (manufactured by Mitsui Petrochemical Co., Ltd.) extruded on the anchor coat layer with a thickness of 30 μm.
By extruding and laminating a linear polyethylene resin film of the innermost layer through M11P, density 0.917), a linear polyethylene resin film having a thickness of 200 μm (SRX manufactured by Dainippon Resin Co., Ltd., density 0. 92
A laminated material of a comparative example (Comparative Sample 3) was obtained in the same manner as in Sample 1, except that the sample No. 0) was sand-laminated. Comparative Sample 4 In Sample 1, the innermost layer was replaced with a linear polyethylene resin film, and a low-density polyethylene resin film having a thickness of 200 μm (M16P manufactured by Dainippon Resin Co., Ltd.
Except for 923), a laminated material (Comparative Sample 4) was obtained in the same manner as in Sample 1. Comparative Sample 5 In Sample 1, the layer formed inside the ethylene-acrylic acid copolymer resin layer was replaced with a low-density polyethylene resin, and a medium-density polyethylene resin having a thickness of 20 μm (manufactured by Mitsui Petrochemical Co., Ltd.) C-260-4P, density 0.93
A laminated material (Comparative Sample 5) was obtained in the same manner as in Sample 1, except that 2) was used.

The laminated materials of Sample 1 and Comparative Samples 1 to 5 prepared as described above were punched to obtain blank plates for forming tube body portions, and the side portions of the blank plates were placed on one side. Was superposed on the other outermost layer and heat sealed to form a container body, and then a tube container was formed. Each of these containers was filled with 100 cc of a glycerin solution containing 5% peppermint oil, and the containers were allowed to stand in an oven at 40 ° C., and the storage characteristics of the containers at the first and third months after storage were determined. Examined.

As a result, in Sample 1, no abnormality was observed at one month after storage, and no abnormality was observed at three months after storage.

On the other hand, in Comparative Samples 1 to 3, one month after storage, delamination occurred between EMAA and LLDPE (Comparative Sample 1), delamination occurred between soft Al-LDPE (Comparative Sample 2), and soft Al -Delamination occurred between LDPEs (Comparative Sample 3). In Comparative Sample 4, no abnormality was observed one month after storage, but delamination occurred between the soft Al-EMAA two months after storage.
In Comparative Sample 5, delamination occurred between Al and medium density PE one month after storage.

[0028]

As described above, the laminated material of the present invention comprises an intermediate support layer made of a biaxially stretched resin film, a barrier layer formed inside the intermediate support layer, and a heat transfer layer located outside the intermediate support layer. An outermost layer made of a plastic resin layer, and an innermost layer made of a linear low-density polyethylene resin located inside the barrier layer, further comprising an acid copolymer in order from the barrier layer side between the innermost layer and the barrier layer Since it is provided with a layer and a low-density polyethylene resin layer, it is possible to provide an inexpensive laminated material used for a tube container having an effect of suppressing permeation and having excellent storage stability of contents.

[Brief description of the drawings]

FIG. 1 is a schematic sectional view showing one embodiment of a laminated material of the present invention.

FIG. 2 is an explanatory view showing a sealing state at a peripheral portion of a laminated material when a tube container body is formed using the laminated material of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Laminated material 2 ... Intermediate support layer consisting of a biaxially stretched film 3 ... Barrier layer 4 ... Outermost layer consisting of a thermoplastic resin layer 4a ... Surface of the outermost layer 5 ... Innermost layer consisting of a linear polyethylene resin layer 5a ... Inner layer surface 6 ... Acid copolymer layer 7 ... Low density polyethylene resin layer

────────────────────────────────────────────────── ─── Continuation of the front page (56) References JP-A-8-91396 (JP, A) JP-A-4-201332 (JP, A) JP-A-3-153346 (JP, A) JP-A-62-162 169635 (JP, A) JP-A-59-198143 (JP, A) JP-A-58-69043 (JP, A) JP-A-62-64740 (JP, A) JP-A-5-77355 (JP, A) Hikaru 4-63236 (JP, U) (58) Field surveyed (Int. Cl. ⁷ , DB name) B32B 15/08

Claims (3)

(57) [Claims] 1. An intermediate support layer comprising a biaxially stretched resin film, a barrier layer formed inside the intermediate support layer,
An outermost layer made of a thermoplastic resin layer located outside the intermediate support layer; and an outermost layer located inside the barrier layer and having a density of 0.92.
An innermost layer of a linear polyethylene resin having a thickness of from 0.95 to 0.95, and further comprising an acid copolymer layer and a low-density polyethylene resin layer in order from the barrier layer side between the innermost layer and the barrier layer. Laminated material. 2. The laminated material according to claim 1, wherein said barrier layer is a metal foil or a metal thin film layer. 3. The laminated material according to claim 1, wherein the metal constituting the metal foil or the metal thin film layer is aluminum.