JP5055804B2 - Packaging bag - Google Patents

Description

  The present invention relates to a packaging bag for containing contents such as solid, granular, and powdery foods. More specifically, the present invention relates to contents of foods that require water vapor gas barrier properties, oxygen gas barrier properties, light shielding properties, and the like. The present invention relates to a packaging bag for storing objects.

  Conventionally, contents that require water vapor gas barrier properties, oxygen gas barrier properties, light shielding properties, such as coffee, green tea, tea, chocolate confectionery, oil confectionery, etc., are, for example, biaxially stretched nylon film or biaxially stretched polyethylene terephthalate. Base materials such as films, aluminum foil, or biaxially stretched nylon film or biaxially stretched polyethylene terephthalate film on which aluminum is deposited, or an intermediate layer such as a laminate on which paper and aluminum foil are bonded, and polyethylene or polypropylene A packaging material in which heat-adhesive resin layers such as these are laminated in order is used, and this packaging material is sold in a packaging bag of a packaging type such as a three-side seal type, a four-side seal type, a pillow type, or a gusset type. .

  However, packaging bags mainly composed of aluminum foil and synthetic resin layers have problems such as high calorie burned during incineration and aluminum adhering to the inner surface of the incinerator, both of which shorten the life of the incinerator. Cause.

As a technique for solving the above problem, a packaging material mainly composed of paper has been proposed without using an aluminum foil, reducing the amount of synthetic resin used (see, for example, Patent Document 1). The technique disclosed in Patent Document 1 defines the physical properties of paper and provides a moisture-proof property by providing a resin film having a characteristic surface of 10A or more as a wax pick value by a melt coating method. Although it is a moisture-proof packaging material that has been secured, it cannot be applied to contents that require oxygen gas barrier properties or light shielding properties, such as water vapor gas barrier properties, oxygen gas barrier properties, light shielding properties, etc. In addition, there has been a demand for a packaging material that can be applied to contents that require two or more barrier properties, or a packaging bag made of such a packaging material.
JP-A-5-154964

  Therefore, the present invention provides a packaging bag that is excellent in one of water vapor gas barrier property, oxygen gas barrier property, light shielding property, or two or more barrier properties, and can be disposed of as a paper product when disposed of. Is to provide.

In order to achieve the above object, the inventor of the present invention provides a paper layer, one of water vapor gas barrier property and oxygen gas barrier property, or water vapor gas barrier property and oxygen gas barrier property. And a heat-adhesive resin layer are laminated in order, and the heat-adhesive resin layer is provided only in the heat-adhesive portion forming region and is thermally bonded by the heat-adhesive resin layer A packaging bag that does not use a foil, wherein the barrier layer is formed of a synthetic resin film provided with an inorganic vapor deposition layer on one side, and the vapor deposition layer is bonded to the paper layer and the synthetic resin film is thermally bonded. are stacked so as to sexual resin layer side, the heat-adhesive resin layer is formed by printing with a gravure printing method, the paper layer is formed over the entire surface of the packaging bag, the total weight of said packaging bag The weight of the layers is characterized in that less than 50% by weight.

  Further, the present invention according to claim 2 is the synthetic resin film stretched in a uniaxial or biaxial direction in which the barrier layer is provided with an inorganic vapor deposition layer on one surface in the packaging bag according to claim 1. It is characterized by.

The present invention according to claim 3 is the packaging bag according to claim 1 or 2 , wherein the vapor deposition layer of the inorganic substance is any one of aluminum, silicon oxide, aluminum oxide, magnesium oxide, titanium oxide, and boron oxide. It is characterized by this.

According to a fourth aspect of the present invention, in the packaging bag according to the first aspect, the thermal adhesive resin layer is composed of a plurality of layers of different resins.

The packaging bag of the present invention has a water vapor gas barrier property and an oxygen gas barrier property such as coffee, green tea, black tea, chocolate confectionery and oil confectionery , or a content that requires water vapor gas barrier property and oxygen gas barrier property. In addition, it can be suitably used, and can be disposed of as a paper product at the time of disposal, which is extremely effective from the environmental viewpoint.

The present invention will be described in detail below with reference to the drawings.
FIG. 1 is a plan view showing an embodiment of a packaging bag according to the present invention, FIG. 2 is a sectional view taken along line XX of FIG. 1, and the packaging bag 1 is a paper layer 11, a barrier layer 12, and a bag. A four-side seal type in which a packaging material 10 in which a heat-adhesive resin layer 13 provided in a rectangular frame-shaped heat-adhesive portion forming region A is laminated in order is thermally bonded by the heat-adhesive resin layer 13. And the weight of the paper layer is 50% by weight or more based on the total weight of the packaging bag.

Next, various materials constituting the packaging bag 1 will be described. The paper layer 11 is not particularly limited, but normally, since printing is performed on the surface of the paper layer 11, it is preferable that it has a printability. Examples thereof include paper, pure white paper, kraft paper, coated paper, glassine paper, and imitation paper, and the basis weight is 30 g / m ² or more and 130 g / m ² or less. If it is less than 30 g / m ² , the mechanical strength is weak, and there is a risk of cutting during processing such as printing, and if it exceeds 130 g / m ² , the paper may be too strong and the suitability for filling may deteriorate. . The paper layer 11 may be provided with a corona discharge treatment or an anchor coat layer on a necessary surface as necessary.

The barrier layer 12 is provided to provide one of water vapor gas barrier, oxygen gas barrier, light-shielding property, or two or more barrier properties required for the contents. Film made of synthetic resin, polypropylene resin, etc., or coated with polyvinylidene chloride on one side of cellophane, or aluminum, silicon oxide, aluminum oxide (alumina), magnesium oxide, titanium oxide, oxide Examples include materials provided with an inorganic vapor deposition film such as boron, polyvinylidene chloride films, ethylene-vinyl alcohol copolymers, etc., which are environmentally friendly, and at least water vapor gas barrier properties and oxygen gas barrier properties. As well as providing light shielding as needed. From Runado, using a synthetic resin film having a vapor deposited film of an inorganic material. As the synthetic resin film, any of an unstretched state and a uniaxially or biaxially stretched film can be used, but it is natural that the barrier layer 12 provides barrier properties in the packaging bag 1. A synthetic resin film that is provided in order to impart a sufficient strength and is preferably stretched in a uniaxial or biaxial direction. A packaging bag using a synthetic resin film stretched in a uniaxial direction can impart easy tearability. The thickness of the synthetic resin film may be set so that the paper layer 11 occupies 50% by weight or more of the total weight when the packaging bag 1 is formed. Is appropriate. The barrier layer 12 may be provided with a corona discharge treatment or an anchor coat layer on a necessary surface as necessary.

  Examples of a method of laminating the paper layer 11 and the barrier layer 12 include a sandwich lamination method in which polyethylene melted and melted from a T-die extruder is laminated, or a two-component curable polyurethane comprising a polyol component and an isocyanate component. Can be laminated by a known lamination method of a dry lamination method of laminating using an adhesive, but when the basis weight of the paper layer 11 is small, a dry lamination method in which the weight of the adhesive layer is smaller than that of the sandwich lamination method. Is preferred. The surface of the barrier layer 12 on the paper layer 11 side is a polyvinylidene chloride coating film surface or an inorganic vapor deposition film surface in order to ensure heat seal strength when formed into a bag.

Next, the thermal adhesive resin layer 13 will be described. Examples of the resin that forms the thermal adhesive resin layer 13 include urethane resins, vinyl chloride-vinyl acetate copolymer resins, acrylic resins, polyester resins, chlorinated polyethylene resins, chlorinated polypropylene resins, Alternatively, other modified polyolefin resins are suitable, and a gravure is used by using a resin composition obtained by arbitrarily adding a desired additive to one or two or more resins (vehicles) and kneading them sufficiently. it forms a thermally adhesive resin layer by printing by a printing method. The heat-adhesive resin layer 13 is formed in a heat-bonding portion forming region (a rectangular frame-shaped heat-bonding portion forming region indicated by symbol A in FIG. 1) when used as a bag, and the heat-adhesive resin layer 13. They are heat bonded together. The coating amount of the heat-adhesive resin layer 13 should be determined as appropriate depending on the required strength of the bag, but is generally in the range of 3 to 10 g / m ² as the solid content.

  The heat-adhesive resin layer 13 may be a single layer or a multilayer composed of different resins (not shown). In short, it is only necessary to obtain a good packaging bag sealed by thermally bonding the heat-adhesive resin layer 13, and a layer having a function of bonding the barrier layer 12 to the synthetic resin film surface; The heat-adhesive resin layer 13 may be formed of a plurality of layers composed of different resins provided with a layer having a sealing function by heat bonding and divided in function. In addition, a different resin means not only a resin having a different resin type, but also a resin having a different mixing ratio in a mixed resin. The application amount in this case is also as described above.

  In addition, the packaging bag 1 of the present invention is usually provided with a design such as a trade name, raw material name, content, expiration date, etc. on its surface by printing, and the thermal adhesive resin layer is also provided in accordance with this design. It is done. At that time, a mark (not shown) is formed in one color constituting the pattern, for example, a color such as red or black. When this mark is produced using the automatic packaging machine or the bag making machine, etc., the mark is formed in the heat-bonding portion forming region (on FIG. 1, This area is formed on the packaging bag for reliable thermal bonding in the area indicated by symbol A), and this mark is detected by an automatic packaging machine or a photoelectric tube mark detection device equipped in a bag making machine or the like. Thus, it is surely thermally bonded in the heat-bonding portion forming region (the region indicated by symbol A in FIG. 1) where the heat-adhesive resin layer is provided. If the picture can be detected by a phototube mark detector or the like, the mark need not be provided.

  Further, the packaging bag of the present invention is not limited to the four-side seal type packaging bag 1 shown in FIG. 1, and includes all packaging bags in a category that does not depart from the gist of the present invention. Type, pillow type, gusset type and the like.

  Next, the present invention will be described in more detail with reference to the following examples.

Two-component curing of 40 g / m ² pure white paper and biaxially stretched nylon film (specific gravity: 1.2) with an alumina vapor deposition layer formed on one side of 15 μm thickness so that the alumina vapor deposition layer is on the pure white paper side A mark printed by gravure printing is applied to the pure white paper surface of a laminate laminated by a dry lamination method using a type urethane adhesive, and a heat bonding part forming region on the nylon film surface (the outer bag size is 115 mm when used as a packaging bag) X 155mm, bag inner side of 108mm x 148mm with a width of 7mm on the peripheral edge of the bag) and the mark printing and registration, and urethane resin and vinyl chloride-vinyl acetate copolymer system by gravure printing method A packaging material in which a heat-adhesive resin layer was formed by printing a mixed resin composition of resin was produced. Using this packaging material, a four-side sealed type packaging bag having a heat seal width of 7 mm and an outer dimension of 115 mm × 155 mm was produced by a sealing machine. The heat-adhesive resin layer had a solid content of 5 g / m ² , and the two-component curable urethane adhesive had a solid content of 2.5 g / m ² .

52.3 g / m ² high-quality paper and a biaxially stretched polyethylene terephthalate film (specific gravity: 1.4) in which a silica vapor-deposited layer is formed on one surface of 12 μm thickness so that the silica vapor-deposited layer is on the fine paper side Heat-bonded low-density polyethylene (specific gravity: 0.93) extruded to a thickness of 20μm and laminated by the sandwich lamination method and marked on the fine paper surface by gravure printing and heat-bonded to the polyethylene terephthalate film surface Gravure printing by registering the mark printing and registering in the part forming area (the outer bag size is 115mm x 155mm and the inner bag size is 108mm x 148mm so that the inner bag size is 108mm x 148mm) The thermal adhesive resin layer is formed by printing a mixed resin composition of urethane resin and vinyl chloride-vinyl acetate copolymer resin A packaging material was prepared. Using this packaging material, a four-side sealed type packaging bag having a heat seal width of 7 mm and an outer dimension of 115 mm × 155 mm was produced by a sealing machine. The thermal adhesive resin layer had a solid content of 5 g / m ² .

^Two liquids of 64 g / m ² fine paper and a biaxially stretched polyethylene terephthalate film (specific gravity: 1.4) having an alumina vapor deposition layer formed on one surface of 12 μm thickness so that the alumina vapor deposition layer is on the fine paper side Marked by gravure printing on the high-quality paper surface of the laminate laminated by dry lamination using a curable urethane-based adhesive, and the heat-bonding area formation area on the polyethylene terephthalate film surface (outside of the bag when used as a packaging bag) dimensions 115 mm × 155mm, bag dimensions are brought in register with the mark printed on the form) by 7mm wide the bag peripheral edge so as to be 108 mm × 148 mm, vinyl chloride and urethane resins by a gravure printing method - vinyl acetate copolymer A packaging material in which a heat-adhesive resin layer was formed was produced by printing a mixed resin composition of a polymer-based resin. Using this packaging material, a four-side sealed type packaging bag having a heat seal width of 7 mm and an outer dimension of 115 mm × 155 mm was produced by a sealing machine. The heat-adhesive resin layer had a solid content of 5 g / m ² , and the two-component curable urethane adhesive had a solid content of 2.5 g / m ² .

[Comparative Example 1]
A biaxially stretched nylon film (specific gravity: 1) having a mark printing by gravure printing on one side of a 40 g / m ² pure white paper and then forming an alumina vapor deposition layer on one side having a thickness of 12 μm on the other side. 2) is laminated by a dry lamination method using a two-component curable urethane adhesive so that the alumina vapor deposition layer is on a pure white paper side, and then 25 μm thick unstretched polypropylene on the biaxially stretched nylon film surface. A packaging material was produced in which a film (specific gravity: 0.92) was laminated by a dry lamination method using a two-component curable urethane adhesive. The two-component curable urethane adhesive had a solid content of 2.5 g / m ² . Using this packaging material, a four-side sealed type packaging bag having a heat seal width of 7 mm and an outer dimension of 115 mm × 155 mm was produced by a sealing machine.

[Comparative Example 2]
A biaxially stretched polyethylene terephthalate film having a silica vapor deposition layer formed on one side of a 12 μm-thickness on one side of a high-quality paper of 64 g / m ² on one side by gravure printing (specific gravity: 1.4) Polyethylene terephthalate film surface of a laminate in which low-density polyethylene (specific gravity: 0.93) heated and melted so that the silica vapor deposition layer is on the fine paper side is extruded to a thickness of 15 μm and laminated by the sandwich lamination method After the isocyanate anchor coating agent was applied to the coating material, it was heated and melt-extruded on the coated surface to prepare a packaging material in which a 25 μm thick ethylene-methacrylic acid copolymer resin (specific gravity: 0.92) layer was formed. Using this packaging material, a four-side sealed type packaging bag having a heat seal width of 7 mm and an outer dimension of 115 mm × 155 mm was produced by a sealing machine.

[Comparative Example 3]
A biaxially stretched polyethylene terephthalate film (specific gravity: specific gravity: 64 g / m ² of high-quality paper, after mark printing was performed by the gravure printing method and an alumina vapor deposition layer was formed on one side of 12 μm thickness on the other side. 1.4) is laminated by a dry lamination method using a two-component curable urethane adhesive so that the alumina vapor-deposited layer is on the fine paper side, followed by a linear low density of 30 μm thickness on the polyethylene terephthalate film surface A packaging material was produced in which a polyethylene film (specific gravity: 0.93) was laminated by a dry lamination method using a two-component curable urethane adhesive. The two-component curable urethane adhesive had a solid content of 2.5 g / m ² . Using this packaging material, a four-side sealed type packaging bag having a heat seal width of 7 mm and an outer dimension of 115 mm × 155 mm was produced by a sealing machine.

Table 1 shows the total weight, paper weight, plastic weight, paper ratio (% by weight), burned calories (kcal / m ² ), and heat seal strength (N / 15 mm width) for the packaging bags prepared above. . Each of the packaging bags of Examples 1 to 3 and Comparative Example 5 has a paper ratio of 50% by weight or more and can be disposed of as a paper product. Compared to the above, the calorie burned is high, and although it can be disposed of as a paper product, it may lead to shortening of the incinerator. In addition, the packaging bags of Examples 1 to 3 have lower values of heat seal strength than the packaging bags of Comparative Examples 1 to 3, but there is no practical problem for individual packaging or lightweight packaging. It is strong enough to be used, and has great practical value as an environmentally friendly packaging bag that can be disposed of as a paper product.

It is a top view which shows one Example of the packaging bag concerning this invention. It is sectional drawing of the XX line of FIG.

Explanation of symbols

1 Packaging Bag 10 Packaging Material 11 Paper Layer 1
12 Barrier layer 13 Thermal adhesive resin layer A Thermal bonding part formation region

Claims (4)

A paper layer, one of water vapor gas barrier property and oxygen gas barrier property, or a barrier layer having water vapor gas barrier property and oxygen gas barrier property, and a heat-adhesive resin layer are laminated in order and the heat bonding A packaging bag that does not use an aluminum foil provided with an adhesive resin layer only in the heat-bonding portion forming region and thermally bonded with the heat-adhesive resin layer,
The barrier layer comprises a synthetic resin film provided with an inorganic vapor deposition layer on one side,
The vapor deposition layer is laminated on the paper layer side so that the synthetic resin film is on the thermal adhesive resin layer side,
The thermal adhesive resin layer is formed by printing by a gravure printing method,
The paper layer is formed over the entire surface of the packaging bag;
The packaging bag, wherein the weight of the paper layer in the total weight of the packaging bag is 50% by weight or more. 2. The packaging bag according to claim 1, wherein the barrier layer is a uniaxial or biaxially oriented synthetic resin film provided with an inorganic vapor deposition layer on one surface. The packaging bag according to claim 1 or 2, wherein the vapor-deposited layer of the inorganic substance is any one of aluminum, silicon oxide, aluminum oxide, magnesium oxide, titanium oxide, and boron oxide . The packaging bag according to claim 1, wherein the heat-adhesive resin layer comprises a plurality of layers of different resins .

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