JP2782227B2 - Paper container with sealing tape - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a paper container having at least a container body formed by a laminated sheet for a paper container, and a laminated sheet for a paper container in the container body. A seal in which at least a back surface layer and an end face of the side portion located on the container inner surface side in a container body sticking portion formed by overlapping and sticking the side portions of the container are covered and stuck with a seal tape. A paper container with a tape is provided.

[Related Art] In a paper container in which a container body is formed by a paper container laminated sheet mainly composed of a paper layer, another side is superimposed and pasted on one side of the paper container laminated sheet. By being worn, a cylindrical container body is formed.

The paper container having the container body formed by the laminated sheet includes an exposed end surface at a side portion of the laminated sheet located on the container inner surface side of the container body sticking portion, and a paper container laminated sheet. Since the paper layer of the container and the filling material in the container are in direct contact with each other, the liquid as the filling material penetrates from the bonding portion to cause liquid leakage, or the gas is contained in the laminated sheet for paper container. In the case where a metal layer is included as a barrier layer, the metal layer and the filling material come into contact with each other at the exposed end face, so that the filling material becomes unpleasant in taste, and furthermore, a peroxide is formed. In the case where the paper container or the laminated sheet for the paper container is previously sterilized with hydrogen water, the hydrogen peroxide that has permeated into the paper layer from the end face of the laminated sheet gradually enters the filling. Because of leaching, the sanitation of the filling is poor. The inner Hama product has drawbacks, such as changing the nature.

For this reason, for example, the end face of the laminated sheet at the bonding portion of the container body using a laminated sheet for a paper container having a laminated structure of polyethylene resin layer / printed paper layer / polyethylene resin layer / Al foil / polyethylene resin layer is used. There has been proposed a paper container with a seal tape that is covered and adhered with a resin tape having a laminated structure composed of a polyethylene resin layer, a biaxially stretched polyethylene terephthalate resin layer, and a polyethylene resin layer.

[Problems to be Solved by the Invention] By the way, the above-described conventional paper container with a seal tape is used for forming a polyethylene resin layer or molding a paper container when manufacturing the laminated sheet for a paper container, and furthermore, for sealing. During the production of a tape and the mounting of the tape, the polyethylene resin (polyolefin resin) undergoes thermal decomposition to produce volatile components such as aliphatic hydrocarbons, and this volatile product is contained in the paper container. Leaching and mixing into the inner filling of the paper container, this is a factor that lowers the quality of the filling such as orange juice and sake as the inner filling in the paper container.

Furthermore, in the paper container with the seal tape according to the related art, wherein the inner peripheral surface layer of the container is formed of a polyethylene resin layer (polyolefin resin layer), the polyolefin resin layer forming the inner peripheral surface layer of the paper container is different from that of the related art. It has the property of adsorbing and transmitting flavor components (flavor components) contained in orange juice, sake, etc., which are the contents inside the container. It is a factor that further lowers the quality of goods.

On the other hand, the present invention has a quality maintaining property that does not degrade the quality of the contents such as orange juice and sake contained in the paper container, and the sealing tape and the paper container The present invention is to provide a paper container with a seal tape which has excellent adhesive strength between the above and a property excellent also in the adhesive strength of a paper container body sticking portion.

[Means for Solving the Problems] The paper container with a seal tape of the present invention comprises a surface layer made of a polyolefin-based resin, an intermediate layer mainly composed of a paper layer, and a low-crystalline saturated glass transition temperature of 40 ° C. or higher. A container body formed by a laminated sheet for a paper container having a back layer made of a polyester resin such that the back layer in the laminated sheet becomes an inner peripheral surface layer of the container, that is, 1 in the laminated sheet for a paper container. A container body comprising a cylindrical body formed by overlapping and affixing the other side on the side, and the side of the paper container laminated sheet. Saturated polyester having heat-adhesive properties on both the front and back surfaces of the back layer and the end surface of at least the side portion located on the inner surface side of the container in the container body sticking portion formed by overlapping and sticking together. Covered with sealing tape that is formed by the fat layer, but that is stuck.

The paper container with a seal tape of the present invention having the above-mentioned structure, the container body has a surface layer made of a polyolefin resin, an intermediate layer mainly composed of a paper layer, and a glass transition temperature of 40.
A cylindrical shape formed by a laminated sheet for a paper container having a back layer made of a saturated polyester resin having a low crystallinity of not less than 0 ° C. so that the back layer in the laminated sheet for a paper container becomes an inner circumferential surface layer of the container. It is formed by the body.

That is, the container body in the paper container with the seal tape of the present invention is formed of a tubular body formed by overlapping and affixing the other side to one side of the paper container laminated sheet. Wherein the inner peripheral surface layer is formed of a low-crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or more, which is a back surface layer in the laminated sheet for a paper container.

The low-crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or more, which is the back surface layer of the laminated sheet for a paper container used for molding the container body, constitutes the resin layer. It has excellent perfume retention performance (flavor retention performance) in an atmosphere at a temperature lower than the glass transition temperature of the saturated polyester resin, and the filling content in the container is usually maintained at less than 40 ° C. For this reason, the paper container of the present invention can use the excellent fragrance retention performance of the back layer in the laminated sheet for paper container.

Further, since the saturated polyester resin layer in the laminated sheet for a paper container is formed of a resin having a low crystallinity of, for example, 30% or less, a thermally bonded portion having excellent adhesive strength to the paper container is formed. Can be done.

The saturated polyester resin layer having a glass transition temperature of 40 ° C. or higher includes, for example, an alcohol component such as ethylene glycol, propylene glycol, 1,4-butanediol, 1,4-cyclohexanedimethanol and an adipic acid, sebacic acid or the like. It is formed by a cocondensation polymer with a dicarboxylic acid component such as an aromatic dicarboxylic acid such as an aliphatic dicarboxylic acid, terephthalic acid, isophthalic acid, and diphenyldicarboxylic acid. Specifically, ethylene glycol and terephthalic acid are used. It is formed by a cocondensation polymer of ethylene glycol, isophthalic acid and terephthalic acid, 1,4-cyclohexanedimethanol and ethylene glycol and terephthalic acid, and propylene glycol and isophthalic acid and terephthalic acid.

In addition, in the case of a cocondensation polymer in which the aliphatic dicarboxylic acid component in the acid component in the saturated polyester resin is 10% by weight or more, it is not preferable because its fragrance retention performance tends to decrease. .

When the thickness of the saturated polyester resin layer having a glass transition temperature of 40 ° C. or more is less than 5 μ, the stability becomes poor. When the thickness exceeds 60 μ, the resin layer becomes hard and the paper container becomes hard. It is preferable that the thickness is in the range of 5 to 60 μm because the container forming characteristics of the laminated sheet for use deteriorate.

The polyolefin-based resin layer forming the surface layer in the paper container laminated sheet is to be an outer surface layer in the obtained paper container, and imparts gloss to the paper container and has water resistance to external moisture. And low-density polyethylene, medium-density polyethylene, high-density polyethylene, ethylene-vinyl acetate copolymer, ethylene-acrylic acid copolymer, ethylene-methyl acrylate copolymer, ethylene-α-olefin Although it is formed of a copolymer, furthermore, polypropylene or the like, it is particularly preferable to be formed of a low-density polyethylene resin from the viewpoint of the heat bonding property.

The intermediate layer in the laminated sheet for a paper container is mainly composed of a paper layer, and may be a single layer of the paper layer. However, usually, an Al foil, an ethylene-PVA copolymer resin film, Axially stretched polyethylene terephthalate resin film,
An intermediate layer composed of a composite layer of a gas barrier layer and a paper layer, such as a vinylidene chloride resin film, a vinylidene chloride coated resin film, a vapor-deposited film on which a metal such as Al or an inorganic substance such as silica is vapor-deposited is used.

The specific laminated constitution of the laminated sheet for paper container having the above constitution is as follows: 1) PE / paper / adhesive PE / low crystalline saturated polyester resin (Tg: 40 ° C. or higher) 2) PE / paper / PE / adhesive PE / Low crystalline saturated polyester resin (Tg: 40 ° C or more) 3) PE / Paper / Polyolefin resin or ionomer resin / Gas barrier layer // Adhesive PE / Low crystalline saturated polyester resin (Tg: 40 ° C or more) 4) PE / paper / polyolefin resin or ionomer resin / gas barrier layer // PE / adhesive PE / low crystalline saturated polyester resin (Tg: 40 ° C or more) 5) PE / paper / polyolefin resin or ionomer Resin / gas barrier layer // adhesive / stretched film / adhesive PE / low crystalline saturated polyester resin (Tg: 40 ° C or more) 6) PE / paper / polyolefin resin or ionomer resin / gas barrier layer // Adhesive / stretched film / PE /
Adhesive PE / low crystalline saturated polyester resin (Tg: 40 ° C or more).

The stretched film in the specific configuration of the laminated sheet for a paper container described above includes stretched films having excellent properties in gas barrier properties, mechanical strength, moisture resistance, heat resistance, and the like, such as polyethylene terephthalate and polypropylene. It is preferable to use a uniaxially or biaxially stretched film made of nylon, nylon or the like.

In a container body sticking portion formed by overlapping and sticking between one side portion and the other side portion of the paper container laminated sheet, at least a side portion of the laminated sheet located on the container inner surface side. The sealing tape covering the back surface layer and the end surface is formed of a saturated polyester resin layer having thermal adhesive properties on both the front and rear surfaces, and is a single-layer tape made of a saturated polyester resin having thermal adhesive characteristics. In addition, a laminated tape having a surface layer and a back surface layer of a saturated polyester resin having a heat bonding property is used.

The specific constitution of the sealing tape used in the paper container of the present invention is as follows: 1) Low-crystalline saturated polyester resin (Tg: 40 ° C. or higher)
2) Low crystalline saturated polyester resin (Tg: 40 ℃ or more)
/ Core layer made of crystalline polyester resin, polyethylene terephthalate resin, adhesive polyester resin, etc. / Three-layer co-extruded laminated resin tape made of low crystalline saturated polyester resin (Tg: 40 ° C or more) 3) Low crystalline saturated polyester resin ( (Tg: 40 ° C or more)
/ Core layer made of crystalline polyester resin, polyethylene terephthalate resin, etc. / Three-layer co-extruded made of low-crystalline saturated polyester resin (Tg: 40 ° C or more) Biaxially stretched laminated resin sheet, including laminated resin tape, a) Synthesis A laminated film in which a stretched resin film and a film made of a low-crystalline saturated polyester resin (Tg: 40 ° C or more) are adhered with an adhesive. B) A stretched synthetic resin film and a low-crystalline saturated polyester resin (Tg: 40 ° C) Above) / Core layer made of crystalline polyester resin, polyethylene terephthalate resin, adhesive polyester resin, etc. / Three-layer co-extruded laminated resin film made of low-crystalline saturated polyester resin (Tg: 40 ° C or more) and bonded with adhesive C) forming an anchor coat layer on the surface of the stretched synthetic resin film, To, adhesive polyethylene / low-crystalline saturated polyester resin (Tg: 40 ° C.
D) Low-crystalline saturated polyester resin (Tg: 40 ° C or higher)
And a crystalline polyester resin obtained by appropriately combining a two-layer co-extruded laminated film and a biaxially stretched laminated film.
Low crystalline saturated polyester resin on both front and back (Tg: 40 ℃)
Above) Laminated resin tape composed of layers, for example, 4) Low crystalline saturated polyester resin (Tg: 40 ° C or more)
Single layer sheet / adhesive / stretched film of synthetic resin /
Single layer sheet made of adhesive / low crystalline saturated polyester resin (Tg: 40 ° C or higher) 5) Low crystalline saturated polyester resin (Tg: 40 ° C or higher)
Single layer sheet / adhesive / stretched film of synthetic resin /
Adhesive / Low crystalline saturated polyester resin (Tg: 40 ° C or higher) / Core layer made of crystalline polyester resin, polyethylene terephthalate resin, adhesive polyester resin, etc.
Laminated tape consisting of three co-extruded laminated resin layers｝ with low crystalline saturated polyester resin (Tg: 40 ° C or higher) 6) Low crystalline saturated polyester resin (Tg: 40 ° C or higher)
Single layer sheet / adhesive / stretched film of synthetic resin /
Anchor coat layer / Laminated tape consisting of {cohesive PE / co-extruded laminated resin layer of low-crystalline saturated polyester resin (Tg: 40 ° C or higher)} 7) Low-crystalline saturated polyester resin (Tg: 40 ° C or higher)
Single layer sheet / adhesive / stretched film of synthetic resin /
A laminated tape or the like comprising an adhesive / {a coaxially extruded laminated resin sheet of a crystalline polyester resin / a low crystalline saturated polyester resin (Tg: 40 ° C. or more) biaxially stretched} or the like is used.

The adhesive PE (polyethylene) used in the specific constitutions of the laminated sheet for paper container and the seal tape described above is graft-modified with an unsaturated carboxylic acid or a derivative thereof (graft amount: 0.01 to 5% by weight). 99 to 50% by weight of a low-crystalline or amorphous ethylene-α-olefin random copolymer and a tackifier, for example, a tackifier resin such as an adhesive tape, paint, hot melt adhesive, etc. A mixture with 50 to 1% by weight of a tackifier consisting of a solid amorphous polymer used, or
Graft modification with 40 to 97% by weight of a low crystalline or amorphous ethylene-α-olefin random copolymer and an unsaturated carboxylic acid or a derivative thereof (graft amount: 0.01
0.1% to 20% by weight of polyethylene
It is preferred to use a mixture of 1 to 50% by weight of a tackifier consisting of a solid amorphous polymer.

In addition, the unsaturated carboxylic acid or its derivative used for obtaining the above-mentioned graft-modified polyolefin polymer is, for example, acrylic acid, maleic acid, fumaric acid, tetrahydrophthalic acid, itaconic acid, citraconic acid, crotonic acid. Carboxylic acids and their derivatives, for example, acid halides, amides, imides, anhydrides, esters and the like; and α in low-crystalline or amorphous ethylene-α-olefin polymers.
-Olefins include, for example, propylene, 1-butene, 1
Hexene, 4-methyl-1-pentene, 1-octene, decene, 1-tetradecene, 1-octadecene and the like are used.

[Example] Hereinafter, a specific configuration of a paper container with a seal tape of the present invention will be described based on an example.

In FIG. 1, a paper container with a seal tape, which is an example of the present invention, is provided on a sticking portion in a container body formed of a tubular body formed by a paper container laminated sheet denoted by reference numeral 1. The seal tape indicated by the symbol a is interposed and adhered.

The container body includes a laminate 4 of the carton base paper 2 and Al foil 3 were laminated by using an adhesive layer S _1, the thickness is formed on the base paper dihedral carton in the laminate 4 is 20
and the surface layer 5 made of low-density polyethylene resin layer of mu, the the Al foil 3 plane in the laminate 4, which consists of laminated resin layer 6 that is bonded by an adhesive layer S ₂ of isocyanate, The laminated resin layer 6 is composed of an adhesive polyethylene resin layer 7 having a thickness of 40 μ and a saturated polyester resin having a thickness of 20 μ (a low-crystalline saturated polyester resin having a glass transition temperature of 81 ° C: PET 6763 “Eastman Kodak”). It is formed of a co-extruded laminated resin layer with the back surface layer 8.

In the laminated sheet 1 for a paper container, the laminated material 4 and the adhesive polyethylene resin layer 7 form an intermediate layer 9 in the laminated sheet 1 for a paper container.

The body sticking part of the body part of the paper container is a laminated sheet 1 for a paper container.
Attached portion in a cylindrical body formed such that the backside layer 8 of the laminated sheet 1 becomes the inner peripheral surface layer of the container by overlapping and affixing the other side to the one side. The inner peripheral surface side of the tubular body, that is, the back surface layer and the end surface at the side portion of the laminated sheet located on the inner surface side of the container are covered with the seal tape indicated by the reference symbol a. Are thermally bonded.

In a paper container with a seal tape having the above configuration,
Each paper container using the seal tape a having the configuration described below was obtained.

Example 1 Low-crystalline saturated polyester resin consisting of a cocondensation polymer of ethylene glycol, 1,4-cyclohexanemethanol and terephthalic acid (glass transition temperature: 81 ° C .: PET G 6763)
Example 2 A low-crystalline saturated polyester resin (glass transition temperature: 71 ° C.) comprising a cocondensation polymer of ethylene glycol, 1,4-cyclohexanemethanol and terephthalic acid (Eastman Kodak Co.) : Sealer PT
60 μm thick single-layer tape by “Mitsui DuPont Polychemical Co.” Example 3 Low crystalline saturated polyester resin (glass transition temperature 81)
° C: PET G 6763 “Eastman Kodak Company”) Layer / adhesive polyester resin (Byron GM-990 “Toyobo”)
Layer / Low crystalline saturated polyester resin (glass transition temperature 81
℃: PET G 6763 “Eastman Kodak Company”) three-layer co-extruded laminated resin tape having a thickness of 60 μm and a laminated structure. Example 4 Low crystalline saturated polyester resin (glass transition temperature 81)
° C: PET G 6763 “Eastman Kodak Company” layer / Polyethylene terephthalate resin (PET J 125 “Mitsui Pet”) layer / Low crystalline saturated polyester resin (glass transition temperature 81 ° C: PET G 6763 “Eastman Kodak Company”) 3) co-extruded laminated resin tape having a thickness of 60 μm and a laminated structure of layers) Example 5 Low-crystalline saturated polyester resin (glass transition temperature 81)
℃: PET G 6763 "Eastman Kodak Company") layer / Polyethylene terephthalate resin (PET J 125 "Mitsui Pet") layer｝ Biaxially stretched film (thickness 20μ) of a two-layer co-extruded laminated sheet / adhesive layer / ｛Polyethylene terephthalate resin (PET J 125 “Mitsui Pet”) layer / Low crystalline saturated polyester resin (glass transition temperature 81 ° C: PET G
6763 "Eastman Kodak Co., Ltd.") A laminated resin tape composed of a biaxially stretched film (thickness: 20μ) of a two-layer co-extruded laminated sheet with a layer｝ Example 6 Low crystalline saturated polyester resin (glass transition temperature 81)
° C: PET G 6763 “Eastman Kodak Company” layer / Polyethylene terephthalate resin (PET J 125 “Mitsui Pet”) layer / Low crystalline saturated polyester resin (glass transition temperature 81 ° C: PET G 6763 “Eastman Kodak Company”) Example 3 Low-crystalline saturated polyester resin (glass transition temperature 81)
° C: PET G 6763 "Eastman Kodak Company") film layer (thickness 40μ) / adhesive layer / biaxially stretched polyester film layer (thickness 12μ) / adhesive layer / low crystalline saturated polyester resin (glass transition temperature 81 ° C: PET G 6763 “Eastman Kodak Company”) laminated resin tape composed of a laminated structure of film layers (thickness: 40μ) Example 8 ｛Low crystalline saturated polyester resin (glass transition temperature 81)
℃: PET G 6763 "Eastman Kodak Company") layer (thickness 2
0μ) / Adhesive layer (Admer AT-537 "Mitsui Petrochemical"):
2 layers co-extruded laminated resin layer / biaxially stretched polyester film layer (thickness 12μ) / adhesive layer (Admer AT-537: 20μ thickness) / low crystalline saturated polyester resin (glass transition temperature) 81 ° C: PET G 6763 “Eastman Kodak Co.”) Two layers co-extruded with a layer (thickness of 20μ)｝ A laminated resin tape having a laminated structure of a laminated resin layer The seal tape described in each of the above embodiments was described above. The table below describes the mechanical suitability of the seal tape when affixed to the side of the laminated sheet for paper containers, and the sealing property for the body sticking portion for paper containers.

As described above, in the first embodiment, the case where the back surface layer and the end surface of the side portion on the inner peripheral surface side of the container in the body sticking portion of the paper container are covered with the seal tape has been described.
As shown in FIGS. 2, 3, 4 and the like, the seal tape in the paper container with the seal tape of the present invention is attached so as to cover the back surface layer, the end surface, and the surface layer of the side portion. Of course, it may be.

In FIGS. 2, 3, and 4, reference numeral A denotes a side portion of the paper container laminated sheet located on the inner surface side of the container in the paper container body sticking portion, and reference numeral B denotes a paper container located on the outer surface side of the container. A side portion of the laminated sheet for paper, a symbol C is a creasing for bending attached to the laminated sheet for a paper container, a symbol 1 is a back surface layer in the laminated sheet for a paper container, a symbol m is an intermediate layer, The symbol n indicates a surface layer, respectively, and the symbol X indicates a seal tape made of a multilayer resin layer.

[Operation and Effect of the Invention] The paper container with a seal tape of the present invention comprises a surface layer made of a polyolefin resin, an intermediate layer mainly composed of a paper layer, and a low-crystalline saturated polyester resin having a glass transition temperature of 40 ° C or higher. By a laminated sheet for a paper container having a back layer according to the above, comprising a container body formed such that the back layer in the laminated sheet for a paper container is a container inner peripheral layer, The back side layer and the end face of the side portion of the laminated sheet located at least on the inner side of the container of the body sticking portion formed by overlapping and sticking the side portions of the laminated sheet for a paper container have front and back surfaces. Are covered and adhered with a seal tape formed of a saturated polyester resin layer having a thermal adhesive property.

Thus, the paper container with the seal tape of the present invention having the above-mentioned structure is characterized in that the inner peripheral surface layer of the container body portion of the paper container has a resin layer exhibiting an extremely excellent action in fragrance retention performance in an atmosphere of less than 40 ° C. That is, since it is formed of a saturated polyester resin layer having a glass transition temperature of 40 ° C. or more, it has an extremely excellent effect on the quality retention characteristics of orange juice, sake, etc., which are the fillings in the container.

Further, in the paper container with the seal tape of the present invention, the end surface of the side surface on the inner surface side of the container in the body sticking portion formed by overlapping and sticking the side portions of the laminated sheet for a paper container has a front face,
Since the back surfaces are covered and adhered with a seal tape formed of a saturated polyester resin layer, the side surfaces of the laminated sheet are not exposed in the paper container. There is no penetration of the liquid that is the filling material inside, there is no destruction of the sticking part caused by the liquid that has penetrated into the paper layer, and there is no metal layer in the laminated sheet for paper containers In such a case, the metal layer and the filling do not come into direct contact with each other, and even when sterilized with a hydrogen peroxide solution, the metal layer penetrates into the paper layer. If the hydrogen peroxide leaches into the filling, or if the sealing tape is applied prior to the sterilization treatment, the hydrogen peroxide solution permeates into the paper layer. Excellent effect on hygiene and quality retention Is shall.

In addition, the paper container with a seal tape of the present invention does not generate polyodor due to the seal tape, that is, does not cause a change in the filling content due to the presence of the seal tape. These also exhibit an excellent action and effect in the quality maintaining characteristics of the filling.

Furthermore, the paper container with the seal tape of the present invention is characterized in that the saturated polyester resin layers on both the front and back surfaces of the seal tape have a thermal adhesive property, and that the inner peripheral surface layer of the paper container has a low crystallinity. By being formed of the polyester resin layer, it also has an action and an effect such that an extremely excellent adhesive strength is formed at an adhesive portion between the inner peripheral surface layer of the container and the seal tape. is there.

[Brief description of the drawings]

FIG. 1 is a model sectional view showing a portion of a body sticking portion of a container body of a paper container with a seal tape of the present invention, and FIGS. 2 to 4 are body sticking portions of a container body of a paper container with a seal tape of the present invention. It is a model sectional view explaining the state of the seal tape stuck on. DESCRIPTION OF SYMBOLS 1 ... Laminated sheet for paper container, 2 ... Base paper for carton 2, 5 ... Surface layer (polyethylene resin layer) in laminated sheet 1 for paper container, 8 ... Saturated polyester resin (low crystallinity with glass transition temperature of 81 ° C) Back layer made of a saturated polyester resin), a ... seal tape.

Claims (1)

(57) [Claims] 1. A laminated sheet for a paper container comprising a surface layer made of a polyolefin resin, an intermediate layer mainly composed of a paper layer, and a back layer made of a low-crystalline saturated polyester resin having a glass transition temperature of 40 ° C. or higher. Thereby, in a paper container having a container body formed such that the back surface layer in the paper container laminated sheet becomes the container inner peripheral surface layer, the side portions of the paper container laminated sheet overlap each other, At least the back surface layer and the end surface of the side portion located on the inner surface side of the container in the container body sticking portion formed by sticking are formed of a saturated polyester resin layer having both front and back surfaces having heat bonding properties. A paper container with a seal tape, which is covered and adhered with a seal tape.