JP2014213923A - Non-aluminum paper container for beverage - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a non-aluminum paper container for beverage excellent in light barrier properties, and sealability, capable of making inside of the container invisible from outside, and having a straw piercing hole into which a straw can be pierced easily.SOLUTION: An easy piercing resin layer 7 is provided on an inner face side of a paper base material layer 3 and a straw piercing hole 9 on which a linear cutting part 11 penetrating at least the paper base material layer 3 is formed, is provided. In addition, the non-aluminum paper container for beverage is excellent in impact resistance, sealability, and light barrier properties, is capable of concealing inside of the container surely, and is capable of facilitating piercing of a straw.

Description

  The present invention relates to a non-aluminum paper container for beverages that contains beverage liquids such as milk and fruit juice juice, and draws and drinks the beverage liquid by inserting a straw.

  As a beverage paper container for drinking by sucking a beverage liquid by inserting a straw, a thermoplastic resin so as to cover a straw insertion hole on the outer surface side of a paper base layer conventionally provided with a straw insertion hole at a predetermined position It is known to have a laminated structure in which layers are laminated and an aluminum foil layer having a thermoplastic resin layer inside and outside is provided as a barrier layer on the inner surface side so as to cover a straw insertion hole. However, a paper container that does not use an aluminum foil layer is required from the viewpoint of recycling and disposal of the paper container.

  There is a non-aluminum paper container using a synthetic resin layer such as ethylene vinyl alcohol copolymer or aliphatic polyamide as a barrier layer instead of the aluminum foil layer, but the synthetic resin layer such as ethylene vinyl alcohol copolymer is extensible. When the straw is pierced and opened, there is a problem that the synthetic resin layer at the straw insertion hole extends and the straw cannot be smoothly pierced. In order to solve this problem, a thin paper layer is laminated and integrated on the synthetic resin layer, the synthetic resin layer is given rigidity by the thin paper layer, and the straw is easily pierced by suppressing the extensibility of the synthetic resin layer. A paper container has been proposed (see, for example, Patent Document 1).

It is also known that a polyester film represented by polyethylene terephthalate can be used as a barrier layer instead of an aluminum foil layer. However, the polyester film has a high puncture strength and has a problem that it is difficult to pierce with a straw. As a solution to this problem, a paper pack packaging material has been proposed in which silica or alumina is vapor-deposited on a stretched polyester film to reduce the piercing strength and allow the straw to be easily pierced (for example, Patent Document 2).

Republished patent WO2002 / 026572 JP 2003-137342 A

However, in the paper container described in Patent Literature 1, by laminating and integrating the thin paper layer on the synthetic resin layer having extensibility, rigidity is given to the synthetic resin layer by the thin paper layer, and the extensibility of the synthetic resin layer is thereby increased. However, it is not sufficient in terms of stability depending on the basis weight and thickness of the thin paper layer.
In addition, in the paper container described in Patent Document 2, the piercing strength is lowered and the straw can be pierced by vapor-depositing silica or alumina on the stretched polyester film. It has not reached.

  In addition, in the paper containers described in Patent Documents 1 and 2, the portion of the straw insertion hole formed by punching a certain area of the paper base layer becomes fragile, and an impact is applied to the portion of the straw insertion hole. May damage the paper container and impair the sealing performance. In addition, when the synthetic resin layer covering the straw insertion hole is transparent, the light shielding property is low, so that a sufficient light barrier property cannot be obtained, which causes the light deterioration of the beverage, and the beverage liquid in the paper container is visible from the outside. It will end up. Although these problems can be prevented by imparting light-shielding properties by kneading colored resin or colored resin into the synthetic resin layer, there is a problem that the cost increases. Further, when the paper base layer is punched to form the straw insertion hole, a large amount of punched pieces that become dust are generated.

  It is an object of the present invention to provide a non-aluminum paper container for beverages having a straw piercing opening which has excellent light barrier properties and sealing properties, prevents the inside of the container from being seen, and facilitates piercing with a straw. .

  In order to achieve the above object, a non-aluminum paper container for beverages according to claim 1 has an easily pierceable resin layer on the inner surface side of the paper base material layer and penetrates at least the paper base material layer. It has the straw piercing opening in which the linear notch part to be formed was formed.

Invention of Claim 2 is the non-aluminum paper container for drinks of Claim 1, Comprising: Basis weight of the said paper base material layer is 130-180 g / m < ² >, Comprising: The outer surface of the said paper base material layer And at least one thermoplastic resin layer on the side, and on the inner surface side of the paper base material layer, the thermoplastic resin layer, the easy pierce resin layer, and the thermoplastic resin layer are provided in this order. It is an easily pierceable polyester resin layer.

  Invention of Claim 3 is the non-aluminum paper container for drinks of Claim 1 or 2, Comprising: The linear notch part which penetrates the said paper base material layer is formed with several cut lines, These plural cut lines It has at least one crossing point where a cut line crosses, and a plurality of cut lines are formed in at least three directions from the crossing point.

  Invention of Claim 4 is a non-aluminum paper container for drinks of any one of Claims 1-3, Comprising: The linear notch part which penetrates the said paper base material layer is a some arc-shaped notch A line and at least three linear score lines extending from the center of the virtual circle defined by the arc-shaped score line in a radial direction so as not to contact the arc-shaped score line at least as long as the radius. It is formed by.

  Invention of Claim 5 is a non-aluminum paper container for drinks of any one of Claims 1-4, Comprising: The linear notch part which penetrates the said paper base material layer is a some arc-shaped notch And at least three linear first cuts extending in a radial direction from the center of a virtual circle defined by the arc-shaped cut line and extending in a radial direction so as not to contact the arc-shaped cut line A line and at least one linear second cut line extending from the virtual circle radially outward and / or radially inward, the starting point of which is on the arc-shaped cut line It is characterized by that.

  Invention of Claim 6 is a non-aluminum paper container for drinks of any one of Claims 2-5, Comprising: The said easily pierceable polyester resin layer has terephthalic acid as a main component as an acid component. Crystalline polyester resin 98 to 80 wt%, polyester segment consisting of 2 to 20 wt% of block copolymer polyester resin made of a soft polymer having a crystalline segment with a melting point of 170 ° C or higher and a melting point or softening point of 100 ° C or lower and a molecular weight of 400 to 8000 A polyester resin layer (B) having a melting point higher by 10 ° C. or more than the melting point of the polyester resin layer (A) is laminated on at least one surface of the layer (A), and the polyester film is at least uniaxially stretched, Higher than the temperature 10 ° C. lower than the melting point of the crystalline polyester resin used in the polyester resin layer (A), One wherein the temperature below the melting point of the polyester resin layer (B) in which has been subjected to heat treatment.

 Invention of Claim 7 is a non-aluminum paper container for drinks of Claim 6, Comprising: As for the said easily pierceable polyester resin layer, the sum total of the thickness of the said polyester resin layer (B) is 1-10 micrometers. And when the said polyester film was measured by differential scanning calorimetry, the peak (C which shows heat_generation | fever in the temperature range more than the glass transition temperature of the said polyester resin layer (B) and less than melting | fusing point of the said polyester resin layer (A) (C ) And a stretched polyester film having a heat quantity represented by the peak (C) smaller than −10 mJ / mg.

  According to the beverage non-aluminum paper container according to claim 1, the straw having an easily pierceable resin layer on the inner surface side of the paper base material layer and at least a linear cut portion penetrating the paper base material layer is formed. Because it has a piercing opening, the linear cut portion that penetrates the paper base layer is superior in impact resistance, sealing performance, and light barrier properties compared to the conventional straw insertion hole, and also reliably conceals the inside of the container. Can do. Further, when the straw is pierced and opened, when the leading end of the straw is pressed against the cut portion, the easy-piercing resin layer that the leading end of the straw has on the inner surface side of the paper base layer is easily teared, and By continuing the pushing of the straw, the paper base material layer is pushed into the inner surface side along the cut portion and opens, so that the straw can be easily pierced into the straw piercing opening.

According to the non-aluminum paper container for beverages according to claim 2, the basis weight of the paper base material layer is 130 to 180 g / m ² , and at least one thermoplastic resin is provided on the outer surface side of the paper base material layer. And having a layer on the inner surface side of the paper base material layer in the order of a thermoplastic resin layer, an easily piercing resin layer, and a thermoplastic resin layer, and the piercing resin layer is an piercing polyester resin layer. The container can be easily molded by adhering the thermoplastic resin layer on the outer surface side of the paper base material layer and the thermoplastic resin layer on the inner surface side by heat sealing.

  According to the non-aluminum paper container for beverage according to claim 3, when the straw is pierced and opened, by pressing the tip of the straw against the crossing points of the plurality of cut lines, the pressing force of the straw is plural. Therefore, the easy-pierce polyester resin layer that the tip of the straw has on the inner surface side of the paper base material layer can be easily split. Then, the divided portion of the paper base material layer formed by a plurality of score lines can be easily pushed into the inner surface side along the cut portion by pushing the straw, so that the straw can be easily pushed into the straw pier with a light force. Can be stabbed.

  According to the non-aluminum paper container for beverage according to claim 4, when the straw is pierced and opened, at least three linear cut lines intersecting at the center of the virtual circle defined by the arc-shaped cut line are provided. When the divided portion of the paper base material layer formed by at least three straight cut lines is pushed to the inner surface side along the straight cut lines by pressing against the crossing points, a plurality of arc cut lines are formed on the paper base. It becomes a hinge that relaxes the rigidity of the material layer and facilitates the bending of the divided portion.

  According to the non-aluminum paper container for beverage according to claim 5, when the straw is pierced and opened, at least three linear first cuts intersecting at the center of the virtual circle defined by the arc-shaped cut line. When pressing the divided portion of the paper base material layer formed by at least three linear first cut lines into the inner surface side along the linear first cut lines by pressing against the intersections of the lines, a plurality of circles The arc-shaped cut line becomes a hinge that relaxes the rigidity of the paper base material layer and facilitates the bending of the divided portion. In addition, the starting point is on the arcuate cut line, and at least one linear second cut line extending radially outward and / or radially inward of the virtual circle has a plurality of arc cut lines. Therefore, the straw can be easily pierced with a lighter force into the straw piercing opening. In particular, when the plurality of arc-shaped score lines are equidistant from the intersection of at least three linear first score lines, that is, when the virtual circle defined by the arc-shaped score lines is a perfect circle, The effect of facilitating the pushing and bending of the divided portion as a hinge that relaxes the rigidity of the paper base material layer is remarkable, and it is preferable because the straw can be easily pierced into the straw piercing opening with a particularly light force.

  According to the non-aluminum paper container for beverages according to claim 6, the easily pierceable polyester resin layer has a crystalline segment of 98 to 80 wt% of crystalline polyester resin mainly composed of terephthalic acid as an acid component, and a melting point of 170 ° C or higher. And a polyester resin layer (A) on at least one side of a polyester resin layer (A) comprising 2 to 20 wt% of a block copolymer polyester resin comprising a soft polymer having a melting point or softening point of 100 ° C. or less and a molecular weight of 400 to 8000. A polyester film in which a polyester resin layer (B) having a melting point 10 ° C. higher than the melting point is laminated and is at least uniaxially stretched, and is higher than the melting point of the crystalline polyester resin used in the polyester resin layer (A) Is higher than the temperature lower by 10 ° C. and lower than the melting point of the polyester resin layer (B). Since it is heat-treated at a temperature, the easily pierceable polyester resin layer comprising the stretched polyester film thus configured has excellent piercing property and can be easily pierced with a straw. Therefore, the straw can be pierced easily and reliably into the straw piercing port with a light force.

  According to the non-aluminum paper container for beverages according to claim 7, the easy-piercing polyester resin layer has a total thickness of the polyester resin layer (B) of 1 to 10 μm, and the polyester film is subjected to differential scanning calorific value. When measured by measurement, it has a peak (C) representing heat generation in a temperature range not lower than the glass transition temperature of the polyester resin layer (B) and lower than the melting point of the polyester resin layer (A). ) Is a stretched polyester film having a heat quantity of less than −10 mJ / mg. Therefore, the easily pierceable polyester resin layer composed of the stretched polyester film thus configured has excellent piercing properties and is easy with a straw. Therefore, the straw can be pierced easily and surely with a light force into the straw piercing opening.

It is a perspective view which shows an example of embodiment of the non-aluminum paper container for drinks concerning this invention. It is sectional drawing which shows the structure of the straw stab of the non-aluminum paper container for drinks of this example. It is plane explanatory drawing which shows the cut | notch part which penetrates the paper base material layer formed in the straw piercing opening of this example. (A), (b) is plane | planar explanatory drawing which shows the other example of the cut | notch part which penetrates the paper base material layer formed in the straw piercing opening.

Hereinafter, an example of an embodiment of a beverage non-aluminum paper container according to the present invention will be described in detail with reference to FIGS.
FIG. 1 is a perspective view showing a beverage non-aluminum paper container of this example, FIG. 2 is a cross-sectional view showing the configuration of a straw stab of the beverage non-aluminum paper container of this example, and FIG. 3 is formed in the straw stab of this example. FIG. 4 (a) and FIG. 4 (b) are plan views showing other examples of linear cut portions penetrating the paper base material layer formed at the straw piercing opening. It is explanatory drawing.

  The non-aluminum paper container 1 for beverages of this example is a container molded into a rectangular parallelepiped, and the packaging material 2 is composed of two thermoplastic resin layers 4 on the outer surface side of the paper base material layer 3 in this example. 5 and has a laminated structure in which the thermoplastic resin layer 6, the easy-to-pierce resin layer 7, and the thermoplastic resin layer 8 are arranged in this order on the inner surface side of the paper base material layer 3. The beverage non-aluminum paper container 1 obtained by molding the packaging material 2 having such a laminated structure has a straw piercing opening 9 in which a linear cut portion penetrating at least the paper base material layer is formed on the upper surface. Yes. The straw piercing opening 9 on the top surface of the beverage non-aluminum paper container 1 is provided at the stage of manufacturing the packaging material 2.

The production of the packaging material 2 will be described.
In this example, a thermoplastic resin layer 4 is laminated on the outer surface side of the paper base material layer 3 to obtain a laminated paper base material layer 10. Next, the linear cut part 11 which penetrates the laminated paper base material layer 10 formed in the straw piercing opening 9 is formed in the laminated paper base material layer 10. The basis weight of the paper base material layer 3 is not particularly limited, but the basis weight is 100 to 250 g / m ² from the viewpoint of the strength of the beverage non-aluminum paper container 1 and the pierceability of the straw. Preferably, it is 130-180 g / m < ² >. That is, when the basis weight is less than 100 g / m ² , the strength of the beverage non-aluminum paper container 1 may be insufficient, and when it is greater than 250 g / m ² , the piercing property of the straw may be inferior.
Next, the thermoplastic resin layer 5 is laminated on the outer surface side of the laminated paper base material layer 10 in which the linear cut portions 11 are formed, and the thermoplastic resin layer 6 and the easy piercing are provided on the inner surface side of the laminated paper base material layer 10. The resin layer 7 and the thermoplastic resin layer 8 are laminated in this order.

  Examples of the easily pierceable resin layer 7 include an easily pierceable ethylene-vinyl alcohol copolymer (EVOH) resin layer, an easily pierceable nylon resin layer, and an easily pierceable polyester resin layer. Examples of the easily pierceable nylon resin include “Emblem NCBC” manufactured by Unitika Co., Ltd., “Uniathlon TB grade” manufactured by Idemitsu Unitech Co., Ltd. and the like.

  In this example, an easy piercing polyester resin layer is used as the easy piercing resin layer 7. The easily pierceable polyester resin layer is composed of 98 to 80 wt% of crystalline polyester resin mainly composed of terephthalic acid as an acid component, a crystal segment having a melting point of 170 ° C. or higher, a melting point or a softening point of 100 ° C. or lower, and a molecular weight of 400 to 8000. Polyester resin layer (B) having a melting point higher by 10 ° C. or more than the melting point of the polyester resin layer (A) on at least one side of the polyester resin layer (A) comprising 2 to 20 wt% of the block copolymer polyester resin comprising a soft polymer of ) And is at least uniaxially stretched, and is higher than the melting point of the crystalline polyester resin used for the polyester resin layer (A) by 10 ° C. and higher than the polyester resin layer (B). It is preferable that the heat treatment is performed at a temperature lower than the melting point of

The easy-piercing polyester resin layer has a total thickness of the polyester resin layer (B) of 1 to 10 μm, and the polyester resin layer (B A stretched polyester film having a peak (C) representing exotherm in a temperature range equal to or higher than the glass transition temperature of) and lower than the melting point of the polyester resin layer (A), and the amount of heat indicated by the peak (C) is less than −10 mJ / mg More preferably.
Here, “the total thickness of the polyester resin layer (B)” means the thickness of one layer when the polyester resin layer (B) is one layer, and in the case of two or more layers, the polyester resin layer. This is the total thickness of all layers in (B). 1-10 micrometers is preferable and, as for the sum total of the thickness of a polyester resin layer (B), it is more preferable that it is 2-8 micrometers.

In the present invention, the polyester resin used in the polyester resin layer (B) is not particularly limited. For example, polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, and a copolymer mainly composed of these components. Etc.
The polyester resin used for the polyester resin layer (A) is a polyester having a melting point that is 10 ° C. or more, preferably 20 ° C. or more lower than the melting point of the polyester resin used for the polyester resin layer (B). There is no limitation, and there are copolymers such as polyethylene terephthalate, polybutylene terephthalate, and polyethylene naphthalate as the main component. Specifically, the acid component includes terephthalic acid, isophthalic acid, orthophthalic acid, 2 Copolymers using 1,6-naphthalenedicarboxylic acid, paraphenylene dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, paraphenylene dicarboxylic acid, succinic acid, glutaric acid, adipic acid, suberic acid, sebacic acid, dodecanedioic acid, etc. Or as an alcohol component, 1 4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, copolymer using multimers like ethylene glycol, or mixtures thereof.

  In the present invention, the crystalline segment having a melting point of 170 ° C. or higher constituting the polyester resin layer (A) has a melting point of 170 ° C. or higher when only the component is used as a polymer. Acid, residues of aromatic dicarboxylic acids such as 2,6-naphthalenedicarboxylic acid, and aliphatic, aromatic, and fatty acids such as ethylene glycol, propylene glycol, butanediol, pentamethylene glycol, P-xylene glycol, and cyclohexanedimethanol A polyester composed of a residue of a cyclic diol can be used, and it is particularly desirable that the terephthalic acid residue occupies 80 mol% or more.

  In addition, the melting point or softening point of the polyester resin layer (A) is 100 ° C. or lower, and the soft polymer having a molecular weight of 400 to 8000 has a melting point or softening point of 100 ° C. or lower when measured only with the segment constituents. Say things. When one having a molecular weight of 400 or less is used, the resulting block copolymer polyester resin has a low melting point and a high adhesiveness, resulting in poor processability for blending into a film. On the other hand, when the molecular weight exceeds 8000, the soft polymer is separated into layers, exhibits extremely high melt viscosity, becomes hard and brittle, makes it difficult to remove from the polymerization vessel after the copolymerization reaction, When a polymerized polyester resin is used for film forming, the transparency is poor, which is not preferable. Particularly preferred is a molecular weight of 800-4000. Moreover, the ratio of the said soft polymer in block copolymerization polyester resin is the range of 8-20 mol%, Most preferably, it is 10-15 mol%.

  Such soft polymers include polyether oxides such as polyethylene oxide glycol, polytetramethylene oxide glycol, polypropylene oxide glycol, copolymer glycol of ethylene oxide and propylene oxide, copolymer glycol of ethylene oxide and tetrahydrofuran, and polyneo Examples thereof include aliphatic polyesters such as pentyl azelate, polyneopentyl adipate, and polyneopentyl sepacate, and polylactones such as poly-ε-caprolactone and polypivalolactone. Preferably, polyethylene oxide glycol, polytetramethylene oxide glycol, and the like are practical. These block copolyesters can be produced by an ordinary condensation polymerization method.

  Specific examples of the block copolymer polyester resin comprising the crystal segment and the soft polymer include a polyethylene terephthalate-polyethylene oxide block copolymer, a polyethylene terephthalate-polytetramethylene oxide block copolymer, and a polybutylene terephthalate-polyethylene oxide block copolymer. Polymer, polybutylene terephthalate-polytetramethylene oxide block copolymer, polyethylene terephthalate-polyethylene oxide, polypropylene oxide block copolymer, polytetramethylene terephthalate / isophthalate-polytetramethylene oxide block copolymer, polyethylene terephthalate-poly -Ε-caprolactone block copolymer, polyethylene terephthalate-polyne Pentyl sepacate block copolymer, block copolymer of polyester and polyethylene glycol from di (4-carboxyphenoxy) ethane and ethylene glycol, polyester from bis (N-paracarboethoxyphenyl) adipamide and ethylene glycol And a block copolymer of polyethylene glycol and the like.

In the present invention, the easily pierceable polyester resin layer is higher than the melting point of the crystalline polyester resin used for the polyester resin layer (A) by 10 ° C. and lower than the melting point of the polyester resin layer (B). It is preferable that the heat treatment is performed at a temperature. By this heat treatment, the polyester resin layer (A) loses its molecular orientation due to stretching, so that the tensile strength decreases. Since the easily pierceable polyester resin layer of the present invention has the polyester resin layer (A) having such characteristics, it is considered to have particularly excellent piercing properties.
The disappearance of the molecular orientation can be confirmed by the fact that both the longitudinal refractive index Nx and the lateral refractive index Ny of the laminated film measured using an Abbe refractometer are 1.580 or less.

  In the present invention, when the polyester film is measured by differential scanning calorimetry, the peak observed is equal to or higher than the glass transition temperature of the polyester resin layer (B) in addition to the glass transition temperature and melting point of each polyester resin. The polyester resin layer (A) preferably has a peak (C) representing heat generation in a temperature region below the melting point. It is considered that the peak (C) is expressed by crystallization of the polyester resin layer (A) having a low melting point, and the easily pierceable polyester resin layer obtained by having the peak (C) has a particularly excellent piercing. It is thought that it has nature. The amount of heat of the peak (C) is preferably less than −10 mJ / mg, and more preferably less than −15 mJ / mg. When the amount of heat indicated by the peak (C) is −10 mJ / mg or more, disappearance of the molecular orientation of the polyester resin layer (A) is insufficient, and good piercing properties may not be obtained.

The stretched polyester film configured as described above has excellent piercing properties and excellent production / workability. As an example of the stretched polyester film, “TF Tear Fine” manufactured by Toyobo Co., Ltd. can be mentioned.
The resin used for the thermoplastic resin layers 4, 5, 6, and 8 is preferably a low-density polyethylene resin or a linear low-density polyethylene resin, but is not particularly limited thereto. Also, medium density polyethylene resin, high density polyethylene resin, polypropylene resin, polystyrene resin and the like can be used.

  In this invention, the thickness of the easily pierceable resin layer 7 becomes like this. Preferably it is 7-20 micrometers, More preferably, it is 10-17 micrometers. Moreover, the tensile strength of the easily pierceable resin layer 7 is preferably 40 to 200 MPa, more preferably 50 to 150 MPa as a numerical value measured based on JIS K7127.

Next, the linear notch 11 that penetrates the laminated paper base layer 10 of the straw piercing opening 9 will be described.
Here, the linear cut does not include a cut out shape having a certain area such as a circle or a triangle. In addition, the linear shape does not matter in the form of a straight line, an arc, or a wavy line.
The linear cut portion 11 penetrating the laminated paper base layer 10 is formed by a plurality of cut lines 12, and has at least one crossing point X where the plurality of cut lines 12 intersect. The cut line 12 has a shape formed in at least three directions.

In this example, as shown in FIG. 3, the linear cut portion 11 penetrating the laminated paper base material layer 10 is formed from a plurality of arc-shaped cut lines 12a and the center of a virtual circle defined by the arc-shaped cut lines 12a. Three straight first cut lines 12b extending in the radial direction so as not to contact the arcuate cut line 12a at least as long as the radius, and the starting point thereof is on the arc cut line 12a and the radius of the virtual circle It is formed with a linear second cut line 12c extending outward in the direction. Further, the linear second cut line 12c may extend inward and outward in the radial direction of the virtual circle, or may be one or two or more.
Three straight first cut lines 12b extending in the radial direction from the center of the virtual circle are crossed at the center of the virtual circle, and the three straight first cut lines 12b are crossed at the center of the virtual circle. Point X will be located. In addition, the linear 1st cut line 12b may be four or more.

FIGS. 4A and 4B are plan explanatory views showing other examples of the linear cut portions 11 penetrating the laminated paper base layer 10 of the straw piercing opening 9.
In the plurality of cut lines 12 constituting the linear cut portions 11 penetrating the laminated paper base material layer 10 shown in FIG. 4A, the radial direction from the center of the virtual circle defined by the arc cut lines 12a. There are four linear first cut lines 12b extending to the straight line, and a second linear cut line 12c whose starting point is on the arc-shaped cut line 12a extends outward in the radial direction of the virtual circle. .
In the plurality of cut lines 12 constituting the linear cut portions 11 penetrating the laminated paper base material layer 10 shown in FIG. 4B, the radial direction from the center of the virtual circle defined by the arc cut lines 12a. There are four straight first cut lines 12b extending to the straight line, and a second straight cut line 12c whose starting point is on the circular cut line 12a extends inward and outward in the radial direction of the virtual circle. .

  According to the beverage non-aluminum paper container 1 of the present example configured as described above, the straw in which the linear cut portion 11 penetrating the laminated paper base layer 10, that is, penetrating at least the paper base layer 3 is formed. Since it has the piercing opening 9, the linear cut portion 11 penetrating the laminated paper base material layer 10 is superior in impact resistance, sealing property and light barrier property as compared with the conventional straw insertion hole, and reliably in the container. Can be concealed. Further, when the straw is pierced and opened, when the leading end of the straw is pressed against the linear cut portion 11, the easy-piercing resin layer in which the leading end of the straw is laminated on the inner surface side of the laminated paper base material layer 10. The laminate paper base material layer 10 is pushed into the inner surface side along the linear cut portion 11 and opened by continuing the pushing of the straw, and the straw is easily pushed into the straw piercing opening 9. Can be stabbed.

  In this example, in the plurality of cut lines 12 constituting the linear cut section 11 penetrating the laminated paper base material layer 10, a virtual arc defined by the plurality of arc cut lines 12a and the arc cut lines 12a. Three straight first cut lines 12b extending from the center of the circle in the radial direction so as not to contact the arc-shaped cut line 12a with a length at least equal to the radius, and the start point thereof on the arc-shaped cut line 12a There is a linear second cut line 12c extending outward in the radial direction of the virtual circle. Therefore, when the straw is pierced and opened, it is pressed against the crossing point X of the three linear first cut lines 12b that intersect at the center of the virtual circle defined by the arc-shaped cut line 12a. Since the pressing force concentrates at a position immediately below the crossing point X of the three linear first cut lines 12b, the easy-piercing resin layer 7 in which the tip of the straw is laminated on the inner surface side of the laminated paper base material layer 10 is used. Can be easily cleaved.

  Then, when the divided portion 13 of the paper base layer formed by the three straight first cut lines 12b is pushed into the inner surface side along the straight first cut lines 12b by pushing the straw, the three straight lines are formed. A plurality of arc-shaped cut lines 12a that are equidistant from the crossing point X of the first cut lines 12b serve as hinges that relax the rigidity of the laminated paper base material layer 10, and facilitate the pushing and bending of the divided portions 13. Furthermore, since the straight second cut line 12c extending from the arcuate cut line 12a outward in the radial direction of the virtual circle facilitates pushing and bending of the divided portion 13 from the arc cut line 12a, the straw Can be easily stabbed into the straw stab mouth 9 with a light force.

Next, examples and comparative examples will be given to illustrate the features of the present invention, but the present invention is not limited thereto.
The straw piercing property in the straw piercing opening of the non-aluminum paper container for beverages produced in Examples and Comparative Examples was evaluated.
[Example 1]
A laminated paper base material layer 10 was obtained by laminating a thermoplastic resin layer 4 (low density polyethylene resin layer) having a thickness of 15 μm on the outer surface side of the paper base material layer 3 having a basis weight of 135 g / m ² . Next, the linear cut part 11 which penetrates the laminated paper base material layer 10 formed in the straw piercing opening 9 shown to Fig.4 (a) in the laminated paper base material layer 10 was provided. The diameter of the straw piercing port 9 (= the diameter of the imaginary circle defined by the arcuate cut line 12a) was 6.0 mm.
Next, a thermoplastic resin layer 5 (low density polyethylene resin layer) having a thickness of 15 μm is laminated on the outer surface side of the laminated paper base layer 10 in which the linear cut portions 11 are formed, and then the laminated paper base material layer 10 18 μm thick thermoplastic resin layer 6 (linear low density polyethylene resin layer) and 14 μm thick easily piercing polyester resin layer 7 (easy piercing polyethylene terephthalate resin layer) so as to cover the linear cut portion 11 on the inner surface side , Tensile strength (JIS K7127) 70 MPa, manufactured by Toyobo Co., Ltd., trade name: TF Tear Fine), 45 μm-thick thermoplastic resin layer 8 (linear low-density polyethylene resin layer) in this order, for beverage use A packaging material 2 for a non-aluminum paper container 1 was prepared.
[Example 2]
A packaging material 2 for a beverage non-aluminum paper container 1 was prepared in the same manner as in Example 1 except that the basis weight of the paper base material layer 3 was 170 g / m ² .

[Comparative Example 1]
The paper base material layer having a basis weight of 226 g / m ² was provided with a φ6 mm through hole serving as a straw piercing opening. Next, a 15 μm thermoplastic resin layer (low-density polyethylene resin layer) is laminated on the outer surface side of the paper base material, and then a 25 μm thick thermoplastic material is formed so as to cover the through hole on the inner surface side of the paper base material layer. A resin layer (linear low density polyethylene resin layer), a 12 μm thick silica vapor deposited polyester film (tensile strength (JIS K7127) 220 MPa), and a 55 μm thick thermoplastic resin layer (linear low density polyethylene) are laminated in this order. Thus, a packaging material for non-aluminum paper containers for beverages was prepared.
[Comparative Example 2]
Instead of a 14 μm thick easily pierceable polyester resin layer (easy pierceable polyethylene terephthalate resin layer, tensile strength (JIS K7127) 70 MPa, manufactured by Toyobo Co., Ltd., trade name: TF Tear Fine), a 9 μm thick polyester resin A packaging material for a beverage non-aluminum paper container was prepared in the same manner as in Example 1 except that the layer (tensile strength (JIS K7127) 210 MPa) was used.

Table 1 shows the results of evaluating the straw piercing property at the straw piercing opening of the beverage non-aluminum paper containers prepared in Examples and Comparative Examples.
Table 1 shows the results of measuring the straw puncture strength using the beverage non-aluminum paper containers prepared in Examples and Comparative Examples.

<Straw piercing>
(Evaluation criteria)
○: When the paneler pierces the drinking non-aluminum paper container with a straw having a diameter of 4 mm almost vertically, the straw pierce can be penetrated without resistance.
(10 out of 10 panelists can easily penetrate the straw piercing hole.)
Δ: When the panelist pierces the drinking non-aluminum paper container with a straw having a diameter of 4 mm almost vertically, a sense of resistance is felt, but the straw pierce can be penetrated.
(10 out of 10 panelists feel resistance, but can somehow penetrate the straw pierce.)
×: When the paneler pierces a non-aluminum paper container for beverage with a straw having a diameter of 4 mm almost vertically, the straw may not penetrate.
In addition, the area near the straw pier of the non-aluminum paper container for beverages is dented,
The tip of the straw is crushed or the straw is bent.
(3-4 out of 10 panelists cannot pierce the straw.)
<Straw piercing strength>
(Measurement condition)
The beverage non-aluminum paper container filled with water was erected with the straw piercing port as the upper surface. A straw having a diameter of 4 mm was fixed to a tensile / compression tester, and pierced vertically at a speed of 200 mm / min toward the center of the straw piercing opening, and the straw piercing strength was measured.

  As apparent from Examples 1 and 2, the beverage non-aluminum paper container of the present invention has a lower straw piercing strength than Comparative Examples 1 and 2, and can easily pierce the straw into the straw piercing opening with a light force. It was confirmed that it was possible.

DESCRIPTION OF SYMBOLS 1 Non-aluminum paper container 2 for drinks Packaging material 3 Paper base material layer 4, 5, 6 Thermoplastic resin layer 7 Easy piercing resin layer 8 Thermoplastic resin layer 9 Straw piercing port 10 Laminated paper base material layer 11 Linear cut | notch part 12 Cut line 12a Arc shaped cut line 12b Straight first cut line 12c Straight second cut line 13 Dividing part X Crossing point

Claims (7)

  A non-aluminum paper container for beverages, which has an easily pierceable resin layer on the inner surface side of a paper base material layer, and has a straw piercing opening in which a linear cut portion penetrating at least the paper base material layer is formed. The paper substrate layer has a basis weight of 130 to 180 g / m ² , has at least one thermoplastic resin layer on the outer surface side of the paper substrate layer, and heats on the inner surface side of the paper substrate layer. 2. The non-aluminum paper container for beverage according to claim 1, wherein the non-aluminum paper container for beverages according to claim 1, wherein the non-aluminum paper container has a plastic resin layer, an easily pierceable resin layer, and a thermoplastic resin layer in this order, and the pierceable resin layer is an easily piercing polyester resin layer. .   The linear cut portion penetrating the paper base material layer is formed by a plurality of cut lines, and has at least one crossing point where the plurality of cut lines intersect, and from the crossing point, the plurality of cut lines are at least 3 The non-aluminum paper container for beverages according to claim 1 or 2, which has a shape formed in a direction. The linear cut portion that penetrates the paper base material layer has a plurality of arc-shaped cut lines and a circular arc shape having a length at least equal to or greater than the radius in the radial direction from the center of a virtual circle defined by the arc-shaped cut lines. The non-aluminum paper container for beverage according to any one of claims 1 to 3, wherein the beverage non-aluminum paper container is formed of at least three linear cut lines extending so as not to contact the cut lines.   The linear cut portion that penetrates the paper base material layer has a plurality of arc-shaped cut lines and a circular arc shape having a length at least equal to or greater than the radius in the radial direction from the center of a virtual circle defined by the arc-shaped cut lines. At least three linear first cut lines extending so as not to come into contact with the cut line, and their starting points are on the arc-shaped cut line, and extend radially outward and / or radially inward of the virtual circle. The non-aluminum paper container for beverage according to any one of claims 1 to 4, wherein the beverage non-aluminum paper container is formed of at least one linear second cut line.   The easily pierceable polyester resin layer is composed of 98 to 80 wt% of crystalline polyester resin mainly composed of terephthalic acid as an acid component, a crystal segment having a melting point of 170 ° C. or higher, a melting point or a softening point of 100 ° C. or lower, and a molecular weight of 400 to 8000. Polyester resin layer (B) having a melting point higher by 10 ° C. or more than the melting point of the polyester resin layer (A) on at least one side of the polyester resin layer (A) comprising 2 to 20 wt% of the block copolymer polyester resin comprising a soft polymer of ) And is at least uniaxially stretched, and is higher than the melting point of the crystalline polyester resin used for the polyester resin layer (A) by 10 ° C. and higher than the polyester resin layer (B). It is characterized by being heat treated at a temperature lower than the melting point of Beverage Non'arumi paper container according to any one of claims 2-5.   When the total thickness of the polyester resin layer (B) is 1 to 10 μm and the polyester film is measured by differential scanning calorimetry, the easily pierceable polyester resin layer has the polyester resin layer (B). A stretched polyester film having a peak (C) representing heat generation in a temperature range of not less than the glass transition temperature of the polyester resin layer (A) and less than the melting point of the polyester resin layer (A), wherein the amount of heat indicated by the peak (C) is less than −10 mJ / mg. The non-aluminum paper container for beverage according to claim 6, wherein the non-aluminum paper container is used.

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