JP3053884B2 - Manufacturing method of gobel top type liquid paper container having scent retention performance - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a gobel-top type liquid paper container in which juice, liquid yogurt and the like are contained.

[0002]

2. Description of the Related Art In a body paper container, a sealing portion of the container is formed by a heat-sealing ability of a laminated sheet for a paper container, and a polyolefin resin is used so that the heat-sealing ability of the polyolefin resin can be utilized. Is manufactured by using a laminated sheet for a paper container having a heat-sealing resin layer.

[0003] In a paper container produced by a laminated sheet for a paper container having a heat sealing resin layer made of a polyolefin resin, an inner peripheral surface layer of the paper container is formed by a heat sealing resin layer made of a polyolefin resin. Therefore, at the time of forming a polyolefin-based resin layer when obtaining these laminated sheets, or in a box-making process of a paper container using the laminated sheets, the polyolefin-based resin is subjected to thermal decomposition and is volatile such as an aliphatic hydrocarbon. There is a drawback in that components are generated, and when the components are transferred to the fillings in the paper container, the fillings have a taste and odor.

[0004] Further, in the container in which the inner peripheral surface layer is made of a polyolefin resin layer, the resin layer for heat sealing made of the polyolefin resin easily adsorbs the flavoring component in the filling contained in the container. Also, because it is easy to transmit at the same time,
There is a problem that the storage performance for the filling material containing the flavoring component is not sufficient.

In order to solve the above-mentioned problems, the present inventors have developed an amorphous to low crystalline material having a glass transition temperature of 40 ° C. or more, which has an excellent effect of retaining the flavoring component in the filling. By using a laminated sheet having an inner surface resin layer made of a saturated polyester resin, a trial production of a paper container having a fragrance retention performance has been attempted.

However, the outer surface resin layer of the laminated sheet for a paper container is optimally made of a polyolefin-based resin in view of the water resistance and heat sealing properties exerted by the resin layer and the price of the resin itself. .

For this reason, the above-mentioned glass transition temperature of 40
In a box making process using a laminated sheet having an inner surface resin layer of an amorphous to low crystalline saturated polyester resin having a temperature of not less than 0 ° C., a heat-bonded portion between the outer surface resin layer and the inner surface resin layer of the laminated sheet is formed. And a heat bonding portion between the polyolefin-based resin layer and the amorphous to low-crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or higher.

[0008] A sufficient thermal adhesive strength required at the bottom of the liquid paper container in which liquid is filled is determined by the above-mentioned polyolefin resin layer and an amorphous to low crystalline having a glass transition temperature of 40 ° C or more. In order to provide for the thermal bonding portion formed between the substrate and the saturated polyester resin layer, thermal bonding must be performed at a high temperature such as 350 ° C. or higher. It has been found that pinholes and scorching of the paper layer occur at the bonded portion.

[0009]

Accordingly, the present invention is excellent in storage performance for an infill containing a flavoring component and has no problem of migration of polyodor due to the inner surface resin layer to the infill. The present invention relates to a method for manufacturing a gobel-top type liquid paper container, and moreover, a polyolefin resin layer and an amorphous material having a glass transition temperature of 40 ° C. or more when forming the bottom of the paper container.
The heat bonding portion between the low-crystalline saturated polyester resin layer and the heat bonding portion has sufficient heat bonding strength required at the bottom of the liquid paper container in which the liquid is filled. An object of the present invention is to provide a method for forming the heat-bonded portion without causing scorching or the like of a paper layer.

[0010]

According to the method of manufacturing a liquid paper container of the present invention, an outer surface resin layer made of a polyolefin resin, a core layer containing paper, and an olefin resin layer are interposed between the core layer and the core layer. Glass transition temperature of 40 ℃
A Gebel-top type liquid paper container in which the outer surface resin layer in the laminated sheet is the outer peripheral surface of the container by the rectangular laminated sheet having the above-mentioned amorphous to low crystalline saturated polyester resin inner surface resin layer. After forming a tubular body by bonding the left and right sides of a blank plate made of a rectangular laminated sheet to each other,
Prior to the step of forming the bottom of the paper container in the filling step of the filling, the portion to be thermally bonded between the outer surface resin layer and the inner surface resin layer of the laminated sheet in the bottom adhesive portion of the paper container is Gebel-top type liquid paper in which the outer surface resin layer surface is subjected to corona discharge treatment so that the wetting tension of the corona discharge treated surface is 46 to 52 dyne, and thereafter the bottom of the paper container is formed in the filling step of the filling. It consists of a container manufacturing method.

[0011] The laminated sheet used in the method of manufacturing a gobel-top type liquid paper container of the present invention, that is, the laminated sheet cut into a blank plate, comprises an outer surface resin layer made of a polyolefin resin, a core layer containing paper, It has a laminated structure including an inner surface resin layer made of an amorphous to low crystalline saturated polyester resin having a glass transition temperature of 40 ° C. or higher, which is laminated on the core layer with an olefin resin layer interposed therebetween. .

In the method of manufacturing a liquid paper container of the present invention using a blank sheet of a laminated sheet having the above-mentioned laminated structure, the paper container is formed such that the outer surface resin layer in the laminated sheet is the outer peripheral surface of the container. Do.

Further, in the method of manufacturing a liquid paper container according to the present invention, the cylindrical body is formed by bonding the left and right sides of a blank sheet obtained by cutting the laminated sheet having the above-described configuration into a rectangular shape. After the formation, prior to the step of forming the bottom of the paper container in the filling process of the filling material, the heat between the outer surface resin layer and the inner surface resin layer of the laminated sheet in the bottom adhesive portion of the paper container. By subjecting the outer surface resin layer surface of the portion to be bonded to corona discharge treatment, the wetting tension of the corona discharge treated surface is set to 46 to 52 dyne, and then the bottom of the paper container is formed in the filling step of the filling.

Amorphous to low crystalline saturated polyester having a glass transition temperature of 40 ° C. or more forming an inner surface resin layer of a laminated sheet used in the method of manufacturing a gobel-top type liquid paper container of the present invention having the above structure. The resin layer has a crystallinity of 1
It is formed of a non-crystalline to low-crystalline saturated polyester resin such as 0% or less. For example, a dialcohol component such as ethylene glycol, propylene glycol, 1,4-cyclohexane dimethanol, and adipic acid,
Polyester resins obtained by co-condensation polymerization with dicarboxylic acid components such as aliphatic dicarboxylic acids such as sebacic acid and aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid and diphenyldicarboxylic acid, specifically ethylene glycol and terephthalic acid; A polyester resin comprising a co-condensed polymer of a combination of ethylene glycol, isophthalic acid and terephthalic acid, 1,4-cyclohexanedimethanol, ethylene glycol and terephthalic acid, propylene glycol, isophthalic acid and terephthalic acid, and the above-mentioned terephthalic acid When a polyester resin is polymerized using ethylene glycol as a base material, a trivalent carboxylic acid such as trimellitic acid is used for one part of an acid component, or trimethylolpropane or the like is used for one part of an alcohol component. Or use of alcohol, even more and 1 part 1 part acid component of the alcohol component, is formed by a polyester resin obtained by, for example utilizing a trivalent carboxylic acid with trihydric alcohol.

When the polyester resin is such that the aliphatic dicarboxylic acid component in the acid component is 10% by weight or more, the resin layer made of the resin does not have sufficient fragrance retention performance. It is not preferable.

The olefin resin layer located between the core layer and the inner surface resin layer has good adhesion to an amorphous to low crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or more. Although a carboxyl group-modified polyolefin resin exhibiting an action is preferable, a composite resin layer of a polyolefin resin having good adhesion performance to paper and a carboxyl group-modified polyolefin resin may be used as the olefin resin layer. In the case of this composite resin layer, the carboxyl group-modified polyolefin resin layer and the inner surface resin layer composed of the saturated polyester resin layer are in contact with each other, and are interposed between the core layer and the inner surface resin layer. Of course.

A specific example of the laminated structure of the laminated resin layer of the olefin resin layer formed on the core layer and the amorphous to low crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or more is as follows. 1) polyethylene resin layer / amorphous to low crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or more 2) adhesive polyethylene resin layer modified with a carboxyl group / glass transition temperature of 40 ° C. or more Co-extruded laminated resin layer with amorphous to low crystalline saturated polyester resin layer 3) Polyethylene resin layer / adhesive polyethylene resin layer modified with carboxyl group / glass transition temperature of 40
A saturated polyester resin layer having an amorphous to low crystallinity of not lower than ℃.

The above-mentioned laminated resin layer may be a co-extruded laminated resin layer, or may have an adhesive interposed between the resin layers.

The amorphous polyester resin layer having a glass transition temperature of 40 ° C. or more in the laminated resin layer has poor stability when its thickness is less than 5 μm. If it exceeds, the resin layer becomes hard, and the molding properties of the paper container tend to deteriorate. For this reason, the amorphous to low-crystalline saturated polyester resin layer having a glass transition temperature of 40 ° C. or higher in the laminated resin layer is usually formed to a thickness of about 5 to 60 μm.

After the left and right sides of the rectangular laminated sheet are bonded to each other to form a tubular body, prior to the step of forming the bottom of the paper container in the filling step of the filling material, the paper container is formed. The corona discharge treatment is performed on the outer surface resin layer surface of the portion to be thermally bonded between the outer surface resin layer (polyolefin resin layer) and the inner surface resin layer of the laminated sheet in the bottom adhesive portion of the laminate sheet. The wetting tension of 46 to 52 dyne is sufficient for the bottom of the paper container filled with liquid even if the sealing temperature for forming the bottom of the paper container is about 300 ° C. It is possible to form the heat bonding strength, so that the heat bonding portion does not generate pinholes or scorched paper.

The wetting tension on the corona discharge treated surface is 46.
If less than dyne, the effect of the corona discharge treatment is not sufficient, and even if it exceeds 52 dyne,
The effect of corona discharge treatment corresponding thereto cannot be obtained. For this reason, the corona discharge treatment is performed such that the wetting tension on the treated surface by the treatment becomes 46 dyne to 52 dyne.

[0022]

According to the present invention, there is provided a method for producing a gobel top type liquid paper container having a perfume-retaining property, comprising an outer surface resin layer of a polyolefin resin, a core layer containing paper, and an olefin resin layer with respect to the core layer. An outer surface resin layer in the laminated sheet is provided with an inner surface resin layer of a non-crystalline to low crystalline saturated polyester resin having a glass transition temperature of 40 ° C. or more laminated through Is used to obtain a Gebel-top type liquid paper container having an outer peripheral surface, the inner peripheral surface layer of the formed paper container has an amorphous to low crystalline saturated polyester having a glass transition temperature of 40 ° C. or higher. It is formed of a resin layer.

Since the saturated polyester resin layer constituting the inner peripheral layer of the paper container thus obtained exhibits excellent fragrance retention in an atmosphere lower than the glass transition temperature of the saturated polyester resin of the resin layer, In connection with this, since a normal liquid paper container is placed in an atmosphere having a temperature of less than 40 ° C., a paper container having an excellent effect on the fragrance retention performance for the filling can be obtained.

Further, the method for producing a gobel-top type liquid paper container having a scent-retaining property according to the present invention is characterized in that the left and right sides of the rectangular laminated sheet having the above-mentioned laminated structure are adhered to each other. After the formation, prior to the step of forming the bottom of the paper container in the filling process of the filling, between the outer surface resin layer and the inner surface resin layer of the laminated sheet of the bottom adhesive portion of the paper container Corona discharge treatment is performed on the outer surface resin layer surface of the portion to be thermally bonded, so that the wet tension of the corona discharge treated surface is 46 to 52 dyne, and then the bottom of the paper container is formed in the filling step of the filling.

In this way, the sufficient adhesive strength of the thermal bonding portion between the outer surface resin layer and the inner surface resin layer at the stage of forming the bottom of the gobel-top type liquid paper container can be improved by, for example, generation of pinholes and scorching of paper. In such a case, it can be formed by heat sealing at an appropriate temperature, and a good quality govel top type liquid paper container can be obtained.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The concrete construction of the method for manufacturing a gobel-top type liquid paper container having a scent-retaining performance of the present invention will be described below with reference to embodiments.

Example 1 In a laminated sheet for a paper container (FIG. 1), an outer surface resin layer 3 consisting of a 15 μm thick polyethylene resin coat layer was formed on one side of a cardboard (basis weight 340 g / m ² ) 2. After that, on the other side, a 20 μm thick carboxyl group-modified polyethylene resin [a copolymer obtained by graft-polymerizing maleic anhydride onto polyethylene (Admer SE 810: Mitsui Petrochemical Industry Co., Ltd.)
)] Layer 4 and an amorphous saturated polyester resin having a glass transition temperature of 81 ° C. (manufactured by Eastman Kodak Company: PETG)
6763) and an inner surface resin layer 5 having a thickness of 20 μm.
Lamination was performed by a co-extrusion coating method to obtain a laminated sheet denoted by reference numeral 6.

Forming of Liquid Paper Container The above-described laminated sheet 6 is formed by pressing a bending press line at the same time as being punched and formed into a size of 295 mm × 295 mm, and is indicated by reference numeral 7 in FIG. A blank plate for a paper container was obtained.

.. In FIG. 2 are pressing lines for bending.

Further, after the outer surface resin layer 3 composed of the polyethylene resin coat layer at the portion to be bonded between the left and right sides of the blank plate 7 is subjected to a surface treatment using a frame,
The left and right sides of the blank plate 7 were heat-sealed to an envelope to form a cylindrical body.

Thereafter, before forming the bottom of the cylindrical body,
Outer surface resin layer 3 of the portion to be thermally bonded between outer surface resin layer 3 and inner surface resin layer 5 of the laminated sheet in the bottom adhesive portion
The surface was subjected to a corona discharge treatment, and a surface treatment was performed so that the wet tension of the corona discharge treated surface became 50 dyne.

Subsequently, a predetermined paper container is formed at a heat sealing temperature of 300 ° C., and a filling step of the filling material is performed.
In FIG. 3, a gobel top type liquid paper container having an external shape indicated by reference numeral 1, that is, 1000 cc
A cubic paper container of the Goebel top type in which orange juice was filled in a chilled manner was obtained.

The hatched portion of the blank plate 7 shown in FIG. 2 is a corona discharge treated portion applied to the outer surface resin layer surface before the bottom portion is formed.

The thermal adhesive strength between the outer surface resin layer and the inner surface resin layer at the bottom of the obtained paper container is 1.5 kg / (15
mm width).

Comparative Example 1 A laminated sheet having the same configuration as the laminated sheet obtained in Example 1 was used, and a corona discharge treatment was performed prior to forming the bottom of the paper container during the process of forming the paper container according to Example 1. Except for excluding,, a Goebel top-shaped rectangular parallelepiped paper container filled with 1000 cc of orange juice in a chilled manner was obtained in accordance with the paper container forming process in Example 1.

The thermal adhesion strength between the outer surface resin layer and the inner surface resin layer at the bottom of the obtained paper container was 0.7 kg / (15
mm width).

[0037]

As described in the above embodiment, the method for manufacturing a gobel-top type liquid paper container having a scent-retaining property according to the present invention comprises the steps of: forming an outer surface resin layer of a polyolefin resin; A glass transition temperature of 40 ° C. laminated on the core layer via an olefin resin layer.
By a rectangular laminated sheet having an amorphous surface resin layer of the above-mentioned amorphous to low crystalline saturated polyester resin,
An outer surface resin layer in the laminated sheet is used to obtain a liquid paper container having a perfume-retaining property in which the outer peripheral surface of the container is the outer peripheral surface. Sufficient adhesive strength between the heat-bonded portions can be formed by heat sealing at an appropriate temperature that does not lead to the occurrence of pinholes or scorching of paper, for example, so that it has good fragrance retention performance. A Goebel top type liquid paper container can be obtained.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view schematically showing an example of a laminated sheet used in the method for manufacturing a gobel-top type liquid paper container of the present invention.

FIG. 2 is a development view of a blank for a paper container obtained by stamping and forming the laminated sheet shown in FIG. 1;

FIG. 3 is a perspective view showing an example of a paper container obtained by the method of manufacturing a gobel-top type liquid paper container having a scent retention performance of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Goebel top type liquid paper container 2 Cardboard 3 Outer surface resin layer made of polyolefin resin 5 Inner surface resin layer made of amorphous saturated sum polyester resin having a glass transition temperature of 40 ° C. or more 6 Laminated sheet for paper container 7 Blank plate

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B65D 5/00-5/76 B32B 27/00-27/36

Claims (1)

(57) [Claims] 1. An outer surface resin layer made of a polyolefin resin, a core layer containing paper, and a glass transition temperature of 40 ° C. laminated on the core layer via an olefin resin layer.
By a rectangular laminated sheet having an amorphous surface resin layer of the above-mentioned amorphous to low crystalline saturated polyester resin,
In a method for manufacturing a gobel-top type liquid paper container in which the outer surface resin layer in the laminated sheet is an outer peripheral surface of the container,
After bonding the left and right sides of a blank plate made of a rectangular laminated sheet to form a tubular body, prior to the step of forming the bottom of the paper container in the filling step of the filling, the paper is The corona discharge treatment is performed on the outer surface resin layer surface of the portion to be thermally bonded between the outer surface resin layer and the inner surface resin layer of the laminated sheet in the bottom adhesive portion of the container, so that the wetting tension of the corona discharge treated surface is obtained. 46 to 52 dyne, and then forming the bottom of the paper container in the filling step of the filling material.