JP2000095232A - Container for liquid - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper container for a liquid, in which a laminate of the paper container is formed in such a manner that its outer face portion composed of paper as a main body can simply be separated from its inner face portion comprising a vapor deposition layer composed of metal or a metallic oxide an a plastic film layer, thereby easily making the container to waste or reusable as resources. SOLUTION: This paper container for a liquid is formed of a laminate in which a thermoplastic resin layer 1, a paper layer 2, an adhesive resin layer 3, a vapor deposition layer 4 composed of metal or a metallic oxide, a plastic film layer 5, and a thermoplastic resin layer 6 are laminated in order named from an outer face of the laminate, and in which the adhesive strength between the adhesive resin layer 3 and the vapor deposition layer 4 is made to be 50-200 g/15 mm in width. The laminate is designed so that the adhesive resin layer 3 and the vapor deposition layer 4 can be peeled and separated from each other at the interface of both the layers.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a laminated body constituting a container, which is separated by a peeling layer into an outer surface portion mainly composed of paper and an inner surface portion mainly composed of plastic, so that the container can be easily discarded. Also, the present invention relates to a liquid paper container used for packaging of liquor, wine, coffee, etc., in which resources are easily reused.

[0002]

2. Description of the Related Art In recent years, environmental protection has been avoided, and the reuse of packaging materials has become a hot topic. A paper container for milk packaging consisting of a polyethylene / paper / polyethylene laminate has also been used in a gobel-top type paper container. For example, recycling activities have been conducted and resources have been reused for effective use. However, goebel top paper containers used for packaging of sake, wine, coffee, etc., protect the contents,
It is necessary to provide a paper container having excellent gas barrier properties in order to prolong the distribution means and the distribution period, and a laminate in which the gas barrier layer is laminated on the content side of the paper layer, for example, polyethylene / paper / adhesive A laminate composed of a conductive resin / aluminum foil / adhesive / polyethylene terephthalate / polyethylene is generally used. In the paper container made of the laminated body having the above-described configuration, in addition to the aluminum foil included in the laminated structure, the ratio of the plastic occupying the laminate is high, and the recycling of the used gobel-top type paper container can be performed. There is a problem that it is difficult and the recovery efficiency is low. Also,
Since it is a paper container formed of a laminate having extremely high rigidity like the laminate having the above configuration, the outer surface and the inner surface of the top portion of the top of a gobel top type paper container such as a paper container for milk packaging are bonded. There is a disadvantage that it is extremely difficult to reduce the bulk of the paper container by peeling off the part and disassembling it with scissors.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a paper container comprising a laminate comprising a thermoplastic resin layer, a paper layer and an adhesive resin layer, and a metal or metal oxide deposited layer. Another object of the present invention is to provide a liquid paper container which can be easily separated into an inner surface portion made of a plastic film layer and can be easily disposed of and reused of resources.

[0004]

Means for Solving the Problems A thermoplastic resin layer, a paper layer, an adhesive resin layer, a vapor-deposited layer made of metal or metal oxide, a plastic film layer, and a thermoplastic resin layer are laminated in this order from the outer surface. Since the liquid paper container is a liquid paper container composed of a laminate configured to be separable into an outer surface portion and an inner surface portion at the interface with the vapor deposition layer, the paper container is disassembled after use, and the adhesive resin layer is formed from the end of the paper container. Separated at the interface with the vapor deposition layer, it can be separated into an outer surface portion composed of a thermoplastic resin layer, a paper layer and an adhesive resin layer, and an inner surface portion composed of a vapor deposition layer composed of a metal or metal oxide and a plastic film layer. Therefore, it becomes easy to dispose of used paper containers or reuse resources.

[0005] In the above liquid paper container, the adhesive resin layer is made of a low-density polyethylene, an ionomer, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer,
Ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer, formed by hot-melt extrusion of ethylene-methyl methacrylate copolymer, adjusting the extrusion temperature of the above resin , The adhesive strength between the adhesive resin layer and the vapor deposition layer is 50 to 200 g
/ 15 mm width, so that the laminate can be easily peeled between the adhesive resin layer and the deposited layer made of metal or metal oxide after use, without impairing the practicality as a liquid paper container Thus, it can be separated into an outer surface portion composed of a thermoplastic resin layer, a paper layer, and an adhesive resin layer, and an inner surface portion composed of a metal or metal oxide vapor deposition layer and a plastic film layer.

In the above-mentioned liquid paper container, the vapor deposition layer is made of a metal oxide vapor deposition layer such as a silicon oxide vapor deposition layer or an aluminum oxide vapor deposition layer, so that a gas whose adhesive strength changes little due to heating at the time of sealing at the top and bottom seals. A liquid paper container suitable for packaging alcohol, wine, coffee, and the like having excellent barrier properties can be provided.

[0007] The liquid paper container is a goebel top type having a front plate, a rear plate, both side plates, a top forming plate and a bottom forming plate, and the outer surfaces of the top forming plate and the bottom forming plate are thermally bonded. By forming the adhesive strength adjusting layer partially in the region to be heat-bonded, the heat-bonded portions between the outer surfaces of the top and bottom are easily peeled off, so that the top and bottom of the container can be easily disassembled, and the laminate is bonded. Peeled off at the interface between the resin layer and the vapor-deposited layer made of metal or metal oxide, consisting of a thermoplastic resin layer, a paper layer, an outer surface part made of an adhesive resin layer, a metal-deposited layer made of metal or metal oxide, and a plastic film layer Separation into the inner surface becomes easier.

In the above-mentioned liquid paper container, the both side plates are formed by forming vertical folding curves at the center portions of the top forming plate and the bottom forming plate connected vertically above and below the both side plates. It is easy to fold inside and fold.

[0009]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a cross-sectional view showing a laminated structure of an embodiment of a liquid paper container according to the present invention, FIG. 2 is a plan view showing a state of a surface of a blank plate of a gobel top type container, and FIG. FIG. 4 is a partial perspective view showing a procedure for peeling and disassembling an adhesive portion between outer surfaces of the container, FIG. 4 is a perspective view showing a folded state of the gobel top type container, and FIG.
Is a perspective view showing a state in which the outer layer made of polyethylene, paperboard and adhesive resin starts to be peeled from the end of the container, FIG. 6 is a perspective view showing a state in which the outer layer is peeled over the entire length of the container,
FIG. 7 is a perspective view showing another method for creating a trigger for peeling the outer layer and the inner layer, wherein 1 and 6 are polyethylene layers and 2 layers.
Is a paper layer, 3 is an adhesive resin layer, 4 is a metal oxide deposited layer, 5 is a plastic film layer, 7, 8 is an adhesive strength adjusting layer, 11,
12, 13, 14 are side plates, 11a, 12a, 13a, 14a are top forming plates, 11b, 12b, 13b, 14b are bottom forming plates, 15 is an adhesive plate, 1
6, 17 are bent curves, 18 is a spout mounting hole, and 19 is a bottom edge bonding portion.

As shown in FIG. 1, the laminated structure of the embodiment of the liquid paper container according to the present invention comprises, in order from the outer surface, a polyethylene layer 1, a paper layer 2, an adhesive resin layer 3, a metal oxide vapor-deposited layer 4, and a plastic film layer. 5 and a polyethylene layer 6,
The adhesive strength between the adhesive resin layer 3 and the metal oxide deposited layer 4 is 50
The configuration is set to be 200 g / 15 mm. By adopting this configuration, by loosening the end face of the laminate, etc.
It is easily peeled off at the interface between the adhesive resin layer 3 and the metal oxide deposited layer 4 to form an outer surface portion composed of the polyethylene layer 1, the paper layer 2 and the adhesive resin layer 3, the metal oxide deposited layer 4 and the plastic film layer 5. And an inner surface portion composed of the polyethylene layer 6. Printed pattern is polyethylene layer 1
Is provided on the outer surface. The shape of the liquid paper container manufactured using this laminate is arbitrary, such as a goebel top type, a flat top type (brick type), and the like.

In the laminated structure of the embodiment, low-density polyethylene is used as the polyethylene layer 1 and low-density polyethylene, medium-low-density polyethylene, linear low-density polyethylene, and a single-site catalyst are used as the polyethylene layer 6. An ethylene-α-olefin copolymer or the like is used, but it is most preferable to use an ethylene-α-olefin copolymer polymerized using a single-site catalyst as the polyethylene layer 6. 250 for paper layer 2
４５０450 g / m ² paperboard is used.

The resin used for forming the adhesive resin layer 3 by melt extrusion includes low-density polyethylene, ionomer, ethylene-acrylic acid copolymer (EA).
A), ethylene-methacrylic acid copolymer (EMAA),
Examples include ethylene-methyl acrylate copolymer (EMA), ethylene-ethyl acrylate copolymer (EEA), and ethylene-methyl methacrylate copolymer (EMMA).
When polyethylene is used as the adhesive resin layer 3,
By setting the melt extrusion temperature to 290 to 305 ° C., and as the adhesive resin layer 3, ionomer, ethylene-
Acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-
When using an ethyl acrylate copolymer or an ethylene-methyl methacrylate copolymer, the melt extrusion temperature should be 2
By setting the temperature to 60 to 290 ° C., the adhesive strength between the adhesive resin layer 3 and the metal oxide deposited layer 4 is set to 50 to 200 g / 1.
It can be adjusted to 5 mm.

As a layer for imparting gas barrier properties to the laminate, a biaxially stretched polyethylene terephthalate film or a biaxially stretched nylon film on which an aluminum deposited layer, a silicon oxide deposited layer, an aluminum oxide deposited layer, etc. are formed can be used. Of these, a metal oxide layer formed of a metal oxide such as a silicon oxide vapor-deposited layer or an aluminum oxide vapor-deposited layer is preferable because the change in adhesive strength due to heating at the time of forming the top and bottom portions is small.

The shape of the liquid paper container of the present invention can be any shape such as a goebel-top container or a flat-top container. Hereinafter, the goebel-top container will be described. As shown in FIG. 2, a blank plate for producing a goebel top type container is composed of side plates 11, 12, 13, 14 and an adhesive plate 15.
Are connected via creases, and the side plates 11,1
Top forming plates 11a, 12a, 13a, 14a and bottom forming plates 11b, 12b, 13b, 14b are connected to the upper and lower edges of 2, 13, 14 via folds, respectively. In the center, a folding curve 16 is formed in the vertical direction, and the top forming plates 12a and 14a and the bottom forming plate
In the center of 12b, 14b, a folding curve 17 is formed in the longitudinal direction, and the side plates 11, 12, 13, 14 and the top forming plates 11a, 12a, 13a, 14a or the bottom forming plates 11b, 12b, 13b, 14b are connected. It is formed in a state excluding predetermined dimensions above and below the folded rule. Bottom forming plate 11
b, 12b, 13b, and 14b have a partial adhesive strength adjusting layer 7 and a partial adhesive strength in a region where the surfaces of the top forming plates 11a, 12a, 13a, and 14a are thermally bonded. An adjustment layer 8 is formed. The printed pattern layer is formed on the surface of the blank except for the region to be thermally bonded.

The adhesive strength adjusting layers 7 and 8 are made of ethylene-vinyl acetate copolymer, chlorinated ethylene-vinyl acetate copolymer,
It is formed by printing using a resin ink composed of chlorinated polyethylene, chlorinated polypropylene, cyclized rubber, polyamide resin, urethane resin, acrylic resin, cellulose resin, alkyd resin alone or a mixture thereof. be able to. The area where the adhesive strength adjusting layers 7 and 8 are formed is 20% or more of the area where the surfaces of the bottom forming plates 11b, 12b, 13b and 14b and the top forming plates 11a, 12a, 13a and 14a are thermally bonded. Good to do.

The blank plate shown in FIG. 2 is formed into a tubular shape by thermally bonding the side plate 11 and the bonding plate 15 to form a bottom plate 11b, 12b,
After the bottoms are formed by bending and heat-bonding 13b and 14b, the tops are formed by bending and heat-bonding the top forming plates 11a, 12a, 13a and 14a to obtain a Goebel top type container. When discarding the goebel top type container, the top forming plates 12a, 14a provided with the adhesive strength adjusting layer 8 are provided.
Of the bottom forming plates 12b, 13b, and 14b on which the adhesive strength adjusting layer 7 is provided, and peels off the portions of the bottom forming plates 12b, 13b, and 14b where the surfaces are thermally bonded to each other. After dismantling the top and bottom parts,
Is bent inward at a folding curve 16 at the center in the width direction, and the top forming plates 12a, 14a and the bottom forming plates 12b, 14b are bent inward at the folding curve 17 at the center in the width direction, respectively. , Can be folded as shown in FIG.

Bottom forming plate provided with adhesive strength adjusting layer 7
The procedure of disassembling the bottom of the Goebel top type container by peeling off the parts of the surfaces of 12b, 13b, and 14b which are thermally bonded is as shown in FIG. 3, from the state shown in FIG. The edge bonding portion 19 is peeled off from the bottom forming plate 13b and raised.
The state shown in (b) is assumed. Further, the portions of the bottom forming plates 12b and 14b where the surfaces are thermally bonded are separated from each other to separate the edge bonding portions 19, and the state shown in FIG. Next, the side plate
12 and 14 are bent inward at the fold curve 16 at the center in the width direction, and the top forming plates 12a and 14a are bent inward at the fold curve 17 at the center in the width direction to form a gauber top type. The container can be in the folded state shown in FIG.

In the folded state of the paper container shown in FIG. 4, the side end of the rear plate 11, the top forming plate 11a and the bottom forming plate 11b bonded to the adhesive plate 15, that is, the end of the laminate is exposed. By bending the corners at the corners of the laminate, the laminate can be peeled off at the interface between the adhesive resin layer 3 and the metal oxide deposition layer 4 of the laminate, and as shown in FIG. 5, the top forming plate 11a and the bottom The outer surface portion composed of the polyethylene layer 1, the paper layer 2, and the adhesive resin layer 3 can be peeled off from the corner end of the forming plate 11b. As shown in FIG. 6, the rear plate 11, the top forming plate 11a, and the bottom forming It can be peeled over the entire length of the side end of the plate 11b. Further, as shown in FIG. 7, after peeling off the adhesive portion between the outer surfaces of the top thermal adhesive portion, the fold portion is grasped and pulled diagonally, whereby the adhesive resin layer 3 and the metal oxide vapor deposition layer 4 Since the film is peeled off at the interface, the outer surface portion composed of the polyethylene layer 1, the paper layer 2, and the adhesive resin layer 3 can be peeled from the laminate using the peeled portion as a trigger. The separated outer surface portion and the inner surface portion mainly composed of plastic composed of the metal oxide deposited layer 4, the plastic film layer 5, and the polyethylene layer 6 can be separately treated, so that disposal or reuse is facilitated.

[0019]

EXAMPLE 1 400 g of paperboard was laminated on one side with 30 .mu.m of polyethylene by extrusion coating, and the other side of the paperboard was coated with a silicon oxide-deposited biaxially stretched polyethylene terephthalate 12 .mu.m silicon oxide-deposited surface with ethylene-methacrylic acid. Copolymer (EMA
A) was extruded at a resin temperature of 285 ° C. with a thickness of 25 μm and laminated by lamination. Then, a polyethylene terephthalate surface and a polyethylene film of 40 μm were combined with polyethylene by 2 μm.
By laminating by extrusion lamination with a thickness of 5 μm and laminating, 30 μm of polyethylene / 400 g of paperboard / 25 μm of ethylene-methacrylic acid copolymer / 12 μm of silicon oxide vapor-deposited biaxially stretched polyethylene terephthalate / 20 μm of polyethylene
A laminate composed of 40 μm of a polyethylene film was produced. The adhesive strength between the ethylene-methacrylic acid copolymer layer and the silicon oxide vapor-deposited biaxially stretched polyethylene terephthalate layer of the obtained laminate is 100 g / 15 mm, which is sufficient for use as a liquid paper container. -The laminate could be peeled off at the interface between the methacrylic acid copolymer layer and the silicon oxide vapor-deposited biaxially stretched polyethylene terephthalate layer. After forming a printed pattern on the 30 μm polyethylene surface of the laminate and forming an adhesive strength adjusting layer on a predetermined area by printing, a blank plate for a gobel-top type container is prepared by punching, and the blank plate is formed into a tube. The top and the bottom were adhered to each other by thermal bonding to produce a Goebel top type container. The ethylene-methacrylic acid copolymer is obtained by peeling off the adhesive portions between the outer surfaces at the top and bottom of the obtained Goebel top-type container, folding the container into a folded state, and bending the corner end of the folded container. The peeling is started at the interface between the layer and the silicon oxide-deposited biaxially stretched polyethylene terephthalate layer, and the laminate constituting the container is made of polyethylene, paperboard and ethylene-
An outer surface portion made of a methacrylic acid copolymer and an inner surface portion made of silicon oxide vapor-deposited biaxially stretched polyethylene terephthalate, polyethylene and a polyethylene film could be separated.

[0020]

According to the present invention, a thermoplastic resin layer, a paper layer, an adhesive resin layer, a deposited layer made of metal or metal oxide, a plastic film layer, and a thermoplastic resin layer are laminated in this order from the outer surface. By manufacturing a liquid paper container with a laminate configured to be separable into an outer surface portion and an inner surface portion at the interface of the paper container, the paper container is disassembled after use, and the adhesive resin layer and the metal or metal are removed from the end of the paper container. Peeled off at the interface with the vapor-deposited layer made of oxide, the outer surface part consisting of a thermoplastic resin layer, a paper layer, and an adhesive resin layer, and composed of a vapor-deposited layer made of metal or metal oxide, a plastic film layer, and a polyethylene layer Since it is possible to separate the used paper container, the used paper container can be easily discarded or resources can be easily reused.
In the above liquid paper container, the adhesive resin layer may be made of low-density polyethylene, ionomer, ethylene-acrylic acid copolymer, ethylene-methacrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-ethyl acrylate copolymer. It is formed by hot-melt extrusion of the coalesced ethylene-methyl methacrylate copolymer. By adjusting the extrusion temperature of the resin, the adhesive strength between the adhesive resin layer and the vapor deposition layer is 50 to 250 g / Since the configuration is 15 mm wide, the laminated body is easily peeled off between the adhesive resin layer and the deposited layer made of metal or metal oxide after use, without impairing the practicality as a liquid paper container. Then, an outer surface portion composed of a thermoplastic resin layer, a paper layer, and an adhesive resin layer, a vapor-deposited layer composed of a metal or a metal oxide, and a plastic film It can be separated on the inner surface portion consisting of. In the above-described liquid paper container, by using a metal oxide deposited layer such as a silicon oxide deposited layer or an aluminum oxide deposited layer as the deposited layer, a change in adhesive strength due to heating at the time of sealing at the top seal and the bottom seal is small. An excellent liquid paper container suitable for packaging alcohol, wine, coffee, and the like can be provided. The configuration of the liquid paper container is a Goebel top type, and a configuration in which an adhesive strength adjustment layer is partially formed in a region where the outer surfaces of the top forming plate and the bottom forming plate are thermally bonded to each other, Since the heat-bonded portions of the top and bottom outer surfaces are easily separated from each other, the top and bottom of the container are easily disassembled, so that the outer surface portion composed of the thermoplastic resin layer, the paper layer, and the adhesive resin layer from the end of the laminate Can be separated by peeling off from the inner surface portion consisting of the vapor-deposited layer made of metal or metal oxide, the plastic film layer and the polyethylene layer. In the above-mentioned liquid paper container, both side plates are folded inward by forming a vertical fold curve at the center of the top forming plate and the bottom forming plate connected vertically above and below the both side plates. , It is easy to separate the laminate into an outer surface portion and an inner surface portion.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view illustrating a laminated configuration of an embodiment of a liquid paper container according to the present invention.

FIG. 2 is a plan view showing a state of a surface of a blank plate of the goebel top type container.

FIG. 3 is a partial perspective view showing a procedure of peeling and disassembling an adhesive portion between outer surfaces of a bottom forming plate of a goebel top type container.

FIG. 4 is a perspective view showing a folded state of the goebel top type container.

FIG. 5 is a perspective view showing a state in which an outer layer made of polyethylene, paperboard, and an adhesive resin starts to be peeled from an end of the container.

FIG. 6 is a perspective view showing a state where the outer surface layer is peeled over the entire length of the container.

FIG. 7 is a perspective view showing another method for creating a trigger for peeling the outer layer and the inner layer.

[Explanation of symbols]

 1,6 Polyethylene layer 2 Paper layer 3 Adhesive resin layer 4 Metal oxide deposited layer 5 Plastic film layer 7,8 Adhesive strength adjusting layer 11,12,13,14 Side plate 11a, 12a, 13a, 14a Top forming plate 11b, 12b, 13b, 14b Bottom forming plate 15 Adhesive plate 16, 17 Fold curve 18 Spout mounting hole 19 Bottom edge adhesive

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 3E060 AA04 AA05 AB04 BC01 BC04 CF02 DA14 DA30 EA03 4F100 AA17D AA19D AA20D AB01D AK01A AK01C AK01E AK04A AK04E AK06C AK42E AK70C AK71E BAB BAE BAE BAB BAE BAB BAE JL11C JL14C JL14D YY00C

Claims (5)

[Claims] 1. A thermoplastic resin layer, a paper layer, an adhesive resin layer, a deposition layer made of metal or metal oxide, a plastic film layer, and a thermoplastic resin layer are laminated in this order from the outer surface. A liquid paper container comprising a laminate configured to be separable into an outer surface portion and an inner surface portion at an interface with a layer. 2. The adhesive resin layer is formed of a low-density polyethylene, an ionomer, an ethylene-acrylic acid copolymer, an ethylene-methacrylic acid copolymer, an ethylene-methyl acrylate copolymer, and an ethylene-ethyl acrylate copolymer. Is formed by hot-melt extrusion of an ethylene-methyl methacrylate copolymer, and by adjusting the extrusion temperature of the resin, the adhesive strength between the adhesive resin layer and the vapor-deposited layer is 50 to 50. 2. The liquid paper container according to claim 1, wherein the liquid paper container has a width of 200 g / 15 mm. 3. The liquid paper container according to claim 1, wherein the deposition layer is a metal oxide deposition layer such as a silicon oxide deposition layer and an aluminum oxide deposition layer. 4. The liquid paper container according to any one of claims 1 to 3, wherein the shape of the liquid paper container is a goebel top type including a front plate, a rear plate, both side plates, a top forming plate, and a bottom forming plate. A liquid paper container, wherein an adhesive strength adjusting layer is partially formed in a region where the outer surfaces of the forming plate and the bottom forming plate are thermally bonded. 5. The liquid paper container according to claim 4, wherein
A liquid paper container having a structure in which a vertical folding curve is formed at the center of the top forming plate and the bottom forming plate connected vertically above and below the both side plates, respectively.