JP3498587B2 - Laminated package - 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 package in which contents are less eluted, more specifically, an innermost layer made of a hydrophilic resin having a polar group having a large solubility parameter value, and an intermediate layer made of a highly moisture-proof resin. The present invention relates to a laminated package excellent in oil resistance and water resistance, which is obtained by filling a multi-layer container having layers with a content containing an oil component and a water component, and optionally a surfactant component and a medicinal component.

[0002]

2. Description of the Related Art A plastic container is widely used as a packaging container for containing various contents in place of a glass container or the like because it is lightweight, is not easily damaged and is easy to handle. In particular, containers made of olefin resin such as polyethylene and polypropylene are relatively inexpensive and can be easily molded into containers, so they can be used as packaging containers in a wide range of fields such as food products, liquid beverages, seasonings, liquid detergents, and cosmetics. It is used.

On the other hand, a multi-layer container having an ethylene-vinyl alcohol copolymer layer as the innermost layer is disclosed in JP-A-54-486.
It is proposed in Japanese Patent Publication No. 1 and Japanese Patent Publication No. 3-64389. Further, as a multi-layer container having a cyclic olefin layer as an intermediate layer, JP-A-7-266517 and JP-A-10-
It is proposed in Japanese Patent No. 59344 and the like.

[0004]

Problems to be Solved by the Invention JP-A-54-4861
In the inventions proposed in Japanese Patent Publication No. 3-64389, etc., ethylene-vinyl alcohol copolymer is used as the innermost layer because the ethylene-vinyl alcohol copolymer is excellent in chemical resistance and solvent resistance. The present invention relates to a multilayer container having a polymer layer. However, the ethylene-vinyl alcohol copolymer has high hygroscopicity and water absorbency, and in a content containing water, when the ethylene-vinyl alcohol copolymer layer directly contacts the content, the ethylene-vinyl alcohol copolymer layer absorbs water. Therefore, there was a problem in the storability of the contents.
Therefore, the moisture-resistant resin layer is arranged on the inner and outer layers, and ethylene-
A multi-layer container having a vinyl alcohol copolymer layer as an intermediate layer has been used.

On the other hand, in recent years, as a packaging container for hand creams, pharmaceutical creams and the like, a light and durable plastic container has been used instead of a glass container. There has been a strong demand for a packaging container that is excellent in oil resistance and water storage stability in addition to its properties.

[0006] However, if the conventional plastic container is filled with the oil component and the water component, and the contents containing the surfactant component and the medicinal component are filled and sealed and stored, the oil component is increased in the multi-layer container in which the innermost layer is a polyolefin resin. Have a problem of oozing out to the outer surface, and the water-inability is not obtained in a multi-layer container in which the innermost layer is an ethylene-vinyl alcohol copolymer, and moreover, it is hydrophilic in the contents of the oil-in-water micellar structure. There is a problem that the content component of the organic substance permeates the ethylene-vinyl alcohol copolymer layer.

[0007]

The present inventors have solved the above problems by forming the innermost layer with a specific hydrophilic resin and the intermediate layer with a highly moisture-proof resin to solve the above problems. Provided is a laminated package having excellent water resistance.

According to the present invention, an ethylene-vinyl alcohol having a polar group having a solubility parameter of 9.0 or more.
Polymer, polyamide resin, polyester resin
An innermost layer made of one or more kinds of hydrophilic resin that has been exposed,
A multilayer container including an intermediate layer made of a cyclic olefin resin which is a highly moisture-proof resin , an outer layer made of an olefin resin, and an adhesive layer interposed between the intermediate layer and the innermost layer and / or the outer layer. , Oil component, water component and surfactant component
The contents of the oil have the form
Emulsion system contents or randomly mixed
Provided is a laminated package excellent in oil resistance and water resistance, which is obtained by filling contents that are a suitable mixed system .

As the multilayer container, a hydrophilic resin having a polar group having a solubility parameter of 9.0 or more is an ethylene-vinyl alcohol copolymer having an ethylene content of 30 to 55 mol%, and a highly moisture-proof resin layer is an ethylene-cyclic resin. Olefin copolymer, olefin resin density 0.880-0.935
A multi-layer structure in which g / cc low-density polyethylene or linear low-density polyethylene and the adhesive resin is an acid-modified olefin resin is preferable.

According to the present invention, the content of the oil-in-water micellar structure (water-based emulsion system) in which the oil component penetrates the surfactant and is covered with the water component, the inner layer is a hydrophilic resin. Provided is a laminated package excellent in oil resistance and water resistance, which is obtained by filling and sealing a multi-layer container in which the intermediate layer is a highly moisture-proof resin and the outer layer is an olefin resin.

Further, according to the present invention, the content of the mixed system in which the oil component and the water component are randomly mixed is selected from a hydrophilic resin for the inner layer, a highly moisture-proof resin for the intermediate layer and an olefin resin for the outer layer. There is provided a laminated package excellent in oil resistance and water resistance, which is obtained by filling and sealing the multilayer container.

Further, according to the present invention, the inner layer is made of a hydrophilic resin, the intermediate layer is made of a highly moisture-proof resin, and the outer layer is made of an olefin resin, and further, a gas barrier resin layer and a scrap resin layer such as molding waste and recycled materials. There is provided a laminated package having excellent oil resistance and water resistance, which is obtained by filling and sealing the above contents in a multi-layer container to which is added.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention relates to an ethylene-vinyl alcohol having a polar group having a solubility parameter of 9.0 or more.
Polymer, polyamide resin, polyester resin
An innermost layer made of one or more kinds of hydrophilic resin that has been exposed,
A multilayer container including an intermediate layer made of a cyclic olefin resin which is a highly moisture-proof resin , an outer layer made of an olefin resin, and an adhesive layer interposed between the intermediate layer and the innermost layer and / or the outer layer. , Oil component, water component and surfactant component
The content of the oil has the form
Content that is the emulsification system of the water, or randomly mixed
It is based on the finding that a laminated package having excellent oil resistance and water resistance can be obtained by filling contents of a mixed system that are in conflict with each other .

The resin used for the innermost layer of the present invention is a hydrophilic resin having a polar group having a solubility parameter of 9.0 or more, particularly an ethylene-vinyl alcohol copolymer having an ethylene content of 30 to 55 mol%, nylon. Examples include one or more kinds of resins selected from polyamide resins such as 6, nylon 66 and nylon 12, and polyester resins.
When the ethylene content in the ethylene-vinyl alcohol copolymer exceeds 55 mol%, the absorption of the water component in the content decreases, so that the oil resistance of the ethylene-vinyl alcohol copolymer decreases and the ethylene content decreases. When the content is less than 30 mol%, impact resistance, drop strength, environmental stress cracking resistance, etc. are deteriorated.

The solubility parameter is the cohesive energy density (cal / cc) raised to the power of 1/2, and represents the magnitude of polarity per unit volume. The solubility parameters of the main thermoplastic resins are shown in Table 1.

[0016]

[Table 1]

Further, the highly moisture-proof resin layer used for the intermediate layer is a cyclic olefin resin, particularly ethylene-containing resin having an ethylene content of 5 to 50 mol%, particularly 15 to 45 mol%.
Cyclic olefin copolymers are preferred. When the ethylene content in the ethylene-cyclic olefin copolymer exceeds 50 mol%, the moisture resistance decreases and the ethylene content becomes 5 mol%.
If it is less than 1, the moldability, impact resistance and the like are deteriorated.

The cyclic olefin polymer or copolymer is disclosed in JP-A-3-726 and JP-A-2-196832.
Cyclic olefin resins and copolymers thereof described in JP-A No. 1994-154 can be used.

As the olefin resin used in the outer layer, low density polyethylene having a density of 0.880 to 0.935 g / cc or linear low density polyethylene is preferable from the viewpoints of flexibility, squeeze property, sealing property and the like. , Low density polyethylene or linear low density polyethylene polymerized using a metallocene catalyst can be effectively used. The density is 0.
When it exceeds 935 g / cc, flexibility and transparency are deteriorated, and when the density is less than 0.880 g / cc, moldability is deteriorated. Here, linear low-density polyethylene is a copolymer of ethylene and a small amount of α-olefin, has a short side chain based on α-olefin, and its polymer structure is linear. The α-olefin contained in the copolymer is preferably an α-olefin having 4 or more carbon atoms, and examples thereof include butene-1, pentene-1, hexene-1, 4-.
Methyl pentene-1 etc. are mentioned.

The adhesive is preferably a modified olefin resin which is acid-modified with a carboxylic acid such as maleic acid or maleic anhydride or an anhydride thereof by graft polymerization or the like, and has a carbonyl group concentration of 5 to 100 meq / 100 g. Modified olefin resins are preferred. Other than this, a polyester adhesive, an epoxy adhesive, an isocyanate adhesive, etc. can also be used. A layer containing a gas barrier resin, a resin composition layer containing a scrap resin, a surface gloss resin layer, a surface frost. A resin layer or the like can be added.

Further, the content is an emulsion or cream containing an oil component and a water component and, if necessary, a surfactant component, and the water component covers the oil component and the surfactant component. Oil-in-water type (O /
W) is an emulsified product or a mixed system (O + W) product in which an oil component and a water component are randomly mixed.

In the resin layers of the multi-layer container constituting the present invention, various substances such as, for example,
Antioxidants, antistatic agents, color pigments, fillers, antibacterial resins and the like can be added.

In FIG. 1 showing an example of the laminated package of the present invention, a multi-layer container 1 includes a mouth / neck portion 2, a shoulder portion 3, a body portion 4, and a bottom portion 5.
And the contents 6. Inner surfaces of the bottom portion 5 are overlapped with each other and fused by heat sealing, ultrasonic sealing, high frequency sealing or the like.

FIG. 2 shows an enlarged sectional view of AA of FIG.
The innermost layer 7 is a hydrophilic resin, the intermediate layer 8 is a highly moisture-proof resin, the outer layer 9 is an olefin resin, and the adhesive layers 10 and 10 are modified polyethylene.

The thickness of the innermost layer in the body of the multilayer container is 1
The thickness of the intermediate layer is preferably in the range of 0 to 60 μm, the thickness of the intermediate layer is 20 to 60 μm, and the thickness of the adhesive layer is preferably in the range of 5 to 30. Further, the thickness of the outer layer is determined by the strength and shape retention required of the container itself. However, the range of 200 to 500 μm is preferable.

[0026]

EXAMPLE 1 An ethylene-vinyl alcohol copolymer (EV having an ethylene content of 44 mol% and a melting point of 165 ° C. forming the innermost layer (EV
OH) is supplied to the first extruder, and the ethylene-cycloolefin copolymer (COC) having a cyclic olefin content of 22 mol% that forms the intermediate layer is supplied to the second extruder, and the melt flow rate that constitutes the outer layer. Low density polyethylene ethylene (LDPE) having a (MFR) of 1 g / 10 min and a density of 0.918 g / cc was supplied to the third extruder, and the adhesive resin layer was modified with maleic anhydride having a carbonyl group concentration of 40 meq / 100 g. Polyethylene (MPE) was supplied to the fourth extruder and melt-extruded, and the obtained parison having a five-layer structure was melt blow-molded in a mold to obtain a multilayer container. The thickness of each layer in the body of the obtained multi-layer container was 40 for the innermost layer.
μm, intermediate layer thickness is 30 μm, adhesive resin layer is 15 μm
m, and the outer layer was 350 μm. The bottom end of this multilayer container was cut to give a multilayer tube container having an inner volume of 120 ml. The mouth of this multi-layer tube container is sealed with a cap, a sealing material, etc., and after filling the contents of the components shown in Table 2 from the bottom, hot air at a temperature of 400 ° C. is blown onto the inner surface of the bottom cutting location to heat seal the inner surface. The laminated package was obtained by heating to a possible temperature and heat sealing. The evaluation results are shown in Table 2.

Example 2 Nylon 12 (Ny12) forming the innermost layer was fed to the first extruder, and the content of cyclic olefin 2 forming the intermediate layer was 2
2 mol% of ethylene-cyclic olefin copolymer (CO
C) is fed to the second extruder and the MFR constituting the outer layer is 1
Low density polyethylene ethylene (LDPE) having a density of 0.918 g / cc at g / 10 minutes was supplied to the third extruder, and the carbonyl group concentration as an adhesive resin layer was 40 meq / 10.
0 g of maleic anhydride-modified polyethylene (MPE) was supplied to the fourth extruder and melt-extruded, and the obtained parison having a five-layer structure was melt blow-molded in a mold to obtain a multilayer container. The thickness of each layer in the body of the obtained multilayer container was 40 μm for the innermost layer, 30 μm for the intermediate layer, 15 μm for the adhesive resin layer, and 350 μm for the outer layer. The bottom end of this multi-layer container was cut to give a multi-layer container having an inner volume of 120 ml. After filling the contents of the components shown in Table 2 in this multilayer container, the mouth was sealed to obtain a laminated package. The evaluation results are shown in Table 2.

Comparative Example 1 Low density polyethylene ethylene having an MFR of 1 g / 10 min and a density of 0.918 g / cc was supplied to the first extruder as a base material layer for the inner and outer layers, and 22 mol% of cyclic olefin was used as an intermediate layer. The ethylene-cyclic olefin copolymer is supplied to the second extruder, and the maleic acid-modified polyethylene as the adhesive resin layer is supplied to the third extruder to melt and melt the melt-extruded five-layer structure parison in the mold. The thickness of each layer in the body of the multilayer container obtained by blow molding is 200 μm for the inner layer,
The adhesive resin layer had a thickness of 15 μm, the intermediate layer had a thickness of 30 μm, and the outer layer had a thickness of 200 μm. The bottom end of this multilayer container was cut to give a multilayer tube container having an inner volume of 120 ml. Seal the mouth of this multilayer tube container with a sealant,
After filling the contents shown in Table 1 from the cut point on the bottom, heat sealing was performed using a heat seal bar at a temperature of 220 ° C. to obtain a laminated package. The evaluation results are shown in Table 2.

Comparative Example 2 The innermost layer had an ethylene content of 44 mol% and a melting point of 16
The ethylene-vinyl alcohol copolymer at 5 ° C. was fed to the first extruder, and the outer layer was fed with low density polyethylene ethylene having an MFR of 1 g / 10 min and a density of 0.918 g / cc to the second extruder to form an inner layer. A multilayer container obtained by supplying a maleic acid-modified polyethylene as an adhesive layer interposed between the outer layer and the outer layer to a third extruder and melt-molding a melt-molded parison having a three-layer structure in a mold. The thickness of each layer in the body of the is 40 μm for the inner layer and 15 μ for the adhesive resin layer.
m, and the outer layer was 350 μm. The bottom end of this multi-layer container was cut to give a multi-layer container having an inner volume of 120 ml. After filling the contents of the components shown in Table 2 in this multilayer tube container, the mouth was sealed to obtain a laminated package. The evaluation results are shown in Table 2.

Measuring method (1). Measurement of oil content and water content Moisture content of emulsified products and mixed products is determined by Karl Fischer method and its weight fraction is determined.The oil content is separated into petroleum ether, and then distilled water is added to a separating funnel. After liquid-liquid separation, only the petroleum ether fractional component was dried in an evaporation dish, and the weight fraction thereof was determined.

(2). Moisture permeation amount Fill the container with the mixed liquid of water, oil and surfactant up to the sight line of the container and seal the mouth with a sealing material.
After storing for 6 hours under the condition of% RH and temperature and humidity control, the weight of the container is measured. Continue to 6 this container under the same conditions
After storage for a month, the container is weighed to determine the amount of water loss. When the amount of water permeation exceeds 3%, the water retention of the content becomes poor.

(3). The packaging body filled with 100 g of the aroma-retaining content was hermetically sealed in a glass container and stored at 37 ° C. for 4 weeks, and then the gas in the glass container was sampled to prepare a sample for gas chromatography (1 mg).
And From the L-menthol concentration in this sample, the amount of L-menthol permeation per container was converted to determine the aroma retaining property. L-menthol transmission is 30μg /
When the number of books exceeds (rating: ×), the aroma retention deteriorates, and 30 μg
/ Piece or less (score: ○), especially 5 μg / piece or less (score:
◎) is preferred.

[0033]

[Table 2]

Note: * 1 Surfactants and other additives other than the water and oil components, totaling 100.

* 2 O + W is a mixed system form in which a water component and an oil component are simply mixed, O / W is an oil-in-water system form in which the oil component surrounds the water component,
W / O represents a water-in-oil type form in which the water component covers the oil component.

* 3 Shows the peeling state of the COC layer interface,
“Dissolved” means a state in which the COC layer is dissolved in the oil component and there is almost no interlayer adhesive strength.

* 4 Exudation of oil component on the outer surface of the container (surface stickiness) is observed.

[0038]

The laminated package of the present invention comprises an innermost layer made of a hydrophilic resin having a polar group having a solubility parameter of 9.0 or more, an intermediate layer made of a highly moisture-proof resin, and an outer layer made of an olefin resin. And a multi-layer container provided with an adhesive layer interposed between the intermediate layer and the innermost layer and / or the outer layer are filled with contents containing an oil component, a water component and, if necessary, a surfactant component. As a result, the oil component does not ooze to the outer surface and become sticky, and it is possible to sufficiently retain the water content of the content, and it has excellent oil resistance and water resistance.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view of a laminated package of the present invention.

FIG. 2 is a cross-sectional view taken along the line AA of the body portion of the multilayer container of FIG.

[Explanation of symbols]

1 Multi-layer container 2 mouth and neck 3 shoulders 4 torso 5 bottom 6 contents 7 innermost layer 8 Middle class 9 outer layer 10 Adhesive layer

─────────────────────────────────────────────────── ─── Continuation of front page (56) Reference JP-A-7-266517 (JP, A) JP-A-10-34845 (JP, A) JP-A-10-119204 (JP, A) JP-A-10- 59344 (JP, A) JP-A-8-197693 (JP, A) JP-A-9-267447 (JP, A) JP-A-9-85914 (JP, A) International Publication 96/001184 (WO, A1) (JP 58) Fields surveyed (Int.Cl. ⁷ , DB name) B32B 1/00-35/00

Claims (5)

(57) [Claims] 1. An ethylene-vinyl alcohol copolymer having a polar group having a solubility parameter of 9.0 or more , and poly.
One or more selected from amide resin and polyester resin
And the innermost layer consisting of several hydrophilic resin, high moisture resistance resin der
A cyclic olefin-based resin intermediate layer, an olefin-based resin outer layer, and an intermediate layer and an innermost layer and / or an adhesive layer interposed between the outer layer and the oil component and water. Content containing a component and a surfactant component, the form of which is an oil-in-water emulsified system, or an oil resistance filled with a randomly mixed content. Laminated package with excellent water resistance and water resistance. 2. The olefin resin has a density of 0.880 to
0.930g / cc low density polyethylene or linear low density
Oil resistance and water resistance according to claim 1, which is polyethylene.
A laminated package with excellent properties . 3. A polarity having a solubility parameter of 9.0 or more.
The hydrophilic resin having a group has an ethylene content of 30 to 55 mol.
% Ethylene-vinyl alcohol copolymer, highly moisture resistant
Fat layer is ethylene-cyclic olefin copolymer, olefin
System resin has a low density of 0.880 to 0.930 g / cc
Polyethylene or linear low density polyethylene, adhesive tree
The fat according to claim 1 or 2, wherein the fat is a modified olefin resin.
Laminated package with excellent oil resistance and water resistance . 4. A contract provided with a layer containing a gas barrier resin.
Oil resistance and water resistance according to any one of claims 1 to 3
A laminated package with excellent properties . 5. A resin composition layer containing scrap resin is provided.
The oil resistance and the oil resistance according to any one of claims 1 to 4.
A laminated package with excellent water resistance .