JPH08337251A - Easy-to-open package bag - Google Patents

Abstract

PURPOSE: To improve tear-opening ability, by providing at least one of seal parts closing the openings in both ends of a tubular body with a jutting seal part and by providing the jutting seal part with a cut which points in a direction to cross a back lining and reaches a heat seal layer, in a pillow type package bag. CONSTITUTION: This pillow type package bag 9 has a tubular shape made by joining both ends of a packaging material 1 in the direction of its width together as a back lining 2, and openings in both ends of the tubular body are closed by seal parts (top seal part 31 and bottom seal part 32). In this case, the top seal part 31 is provided with a jutting seal part 4 which juts into a contents storage part, and this jutting seal part 4 is provided with a cut 5 which points in a direction to cross the back lining 2 and reaches a heat seal layer. The package bag material 1 is made by bonding the heat seal layer, made of nonoriented polypropylene, a tearable sheet, and an external layer one on top of the other via an adhesive, and minute scratches are made on at least part of the external layer which coincides with the back lining.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaging bag, and more particularly to a packaging bag having an improved tear openability when the heat-sealing layer is unstretched polypropylene (hereinafter sometimes referred to as CPP).

[0002]

2. Description of the Related Art Conventionally, heat-sealing has been generally performed in a packaging bag for food or the like, which is made of a packaging material mainly composed of a plastic film, in order to form a bag-like shape. In order to enable this heat sealing, the packaging material is generally provided with a heat sealing layer made of a heat adhesive resin. Polyolefin resins such as polyethylene and polypropylene are generally used as the resin for the heat seal layer, but the resins that can be used are limited depending on the package contents.

For example, when the content contains fats and oils,
It was common to use polypropylene, which has excellent oil resistance. In addition, polypropylene has less offensive odor than low-density polyethylene, has excellent taste retention (property that does not impair the taste of the contents), or has excellent heat resistance, so contents that are sensitive to taste and aroma are Wrap or
Even when the packaging bag is heat-treated, polypropylene is often used as the heat-sealing layer.

Polypropylene, which can be heat-sealed,
Obtained as an unstretched polypropylene film, which is easy to tear in the direction parallel to the longitudinal direction, but is difficult to tear in the width direction. Therefore, when a packaging bag using an unstretched polypropylene film is created, the bag opening direction and the direction in which the unstretched polypropylene film can be torn apart for the convenience of the form of the bag and the manufacturing process.
Not necessarily the same.

[0005] Further, the packaging material constituting the bag is laminated with a fine scratched plastic film, or a tearable sheet such as a stretched film or an aluminum foil which is easily tearable in a predetermined direction, to tear the packaging bag. Have been proposed.

[0006]

However, the form of the packaging bag is such that both ends of the packaging material in the width direction are back-sealed to form a tubular shape, and a sealing portion for closing the openings at both ends of the tubular body is provided. It is a so-called pillow type packaging bag, and when an unstretched polypropylene film is used as the heat-sealing layer of the packaging material, it is difficult to tear and open the bag even if the above-mentioned tearability improving means is adopted. There was something that happened. That is, as described above, the unstretched polypropylene film can be easily torn in one direction, and when this direction and the tearing direction do not match, the unstretched polypropylene film exhibits high tear resistance.

Therefore, according to the present invention, even when the above unstretched polypropylene film is used for the heat seal layer,
(EN) A pillow type packaging bag which can be easily torn and opened.

[0008]

That is, according to the present invention, the widthwise ends of a packaging material whose heat-sealing layer is unstretched polypropylene are back-sealed to form a tubular shape, and the openings at the ends of the tubular body are formed. A pillow type packaging bag provided with a closing seal part, wherein at least one of the sealing parts closing the opening part is provided with a protruding seal part protruding toward the contents storage part side, and the protruding seal part is provided with the above-mentioned It is an easy-to-open packaging bag, characterized in that it has a notch that extends in a direction traversing the back-sealed seal portion and reaches the heat-sealing layer.

The effect of the present invention is remarkable when the tearable direction of the heat-sealing layer is parallel to the back-sealed seal portion. In the present invention, it is preferable that the packaging material includes a base film made of a stretched film, and at least a portion corresponding to the back-adhering seal portion of the base film is finely scratched. In the packaging material of the present invention, the heat-sealing layer may be provided with an aluminum vapor deposition layer. In addition, the packaging material preferably includes a tearable sheet that is easily torn in the direction crossing the spine-attached seal portion. The present invention can also be applied to a pillow gusset type packaging bag having folds on both sides of the bag.

[0010]

In the packaging bag of the present invention, the notch reaching the heat-sealing layer, which is provided in the projecting seal portion, causes the tearing to be opened and tearing is performed. At this time, if the packaging material includes a base film made of a stretched film that is finely scratched, or a tearable sheet that is easily torn in a direction crossing the spine-bonded seal portion, the tearing and unsealing becomes easier. Further, by adopting a structure in which a gas barrier layer such as an aluminum foil or an aluminum vapor-deposited layer is laminated, it is possible to prevent oxidative deterioration of the contents and deterioration of texture due to moisture absorption.

[0011]

Embodiments of the present invention will now be described with reference to the drawings. 1 is an explanatory plan view showing an embodiment of the packaging bag of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view showing an example of a packaging material constituting the packaging bag of the present invention. It is a figure.

The packaging bag 9 of the present invention shown in FIG. 1 has a tubular shape with a back-applied seal (back-applied seal portion 2) at both ends of the packaging material 1 in the width direction, and openings at both ends of the tubular body. A pillow type packaging bag having a seal portion (top seal portion 31, bottom seal portion 32) for closing, wherein the top seal portion 31 is provided with a protruding seal portion 4 protruding toward the content storage portion side. The projecting seal portion 4 is provided with a cut 5 that extends in the direction crossing the spine-attached seal portion 2 and reaches the heat seal layer 11.

As shown in FIG. 2, the back-sticking seal is a heat-sealing method in which the heat-sealing layers 11 of the packaging material 1 are faced to each other, and is also called a palm-sealing sticker.

The notch 5 has a heat seal layer 11
It is preferable that the heat-sealing layer 11 is a cut line of at least half, and preferably completely cut. The shape of the notch 5 may be a known I notch or V notch. The packaging bag is configured to be torn and opened in the opening direction shown by the broken line C in FIG. 1 by using the notch 5 as an opening trigger, and the contents are taken out.

The embodiment described here is made from the packaging material 1 having the structure shown in FIG. This packaging material 1
Is a heat seal layer 1 made of unstretched polypropylene
1, the tearable sheet 13, and the outer layer 14 are laminated with adhesives 17 and 18, respectively.

The outer layer 14 of the packaging material 1 shown in FIG. 3 is made of a biaxially stretched polyethylene terephthalate film. Here, as the outer layer 14, a transparent plastic film having printability can be preferably used, and in addition to the polyethylene terephthalate film, a film such as a stretched nylon film or a stretched polypropylene film, or cellophane or paper can be used.

If necessary, the outer layer 14 can be finely scratched to improve the tearability. This scratch processing is preferably provided on the back-applied seal portion 2 and its vicinity (the portion indicated by reference numeral S in the figure). That is, FIG.
As is clear from the above, when the pillow type packaging bag is opened in the tearing direction C shown in the figure, the pillow type packaging bag is opened across the spine-attached seal portion 2. The back-sticking seal portion 2 is thick because both ends of the packaging material 1 are overlapped with each other as shown in FIG. 2, and is more difficult to cut than other portions. Therefore, it is preferable to perform the scratch processing on at least the back-attached seal portion 2 and its vicinity. Of course, it may be provided on the entire surface.

The scratch processing itself is known, and a method of pressing a file-like jig or rubbing it to scratch it, a method of processing with a jig provided with an infinite number of fine cutting blades, and a fine processing by laser processing. There are known a method of providing innumerable scratches, a method of chemically treating with a chemical to roughen the surface, and the like. The scratch processing may be performed on the outer layer 14 in advance, or may be performed after the packaging material 1 is created. Although the scratch processing is provided in the outer layer 14, it is not necessary to penetrate the outer layer 14 as long as the tearability is improved. Of course, the layer penetrating the outer layer 14 and further below it;
For example, the tearable sheet 13 may be reached.

A printing layer 15 is provided on the inner surface of the outer layer 3. The printing layer 15 can be provided at an arbitrary position of the packaging material 1, but it is preferably provided at the illustrated position from the viewpoint of designability and protection of the printing layer 15 itself.
The print layer 15 may be provided so as to cover the entire surface of the outer layer 3 as shown in the figure, but may be provided partially.

The non-stretched polypropylene which is the heat seal layer 11 is a heat-adhesive resin which is excellent in oil resistance and the like, and the present invention is to improve the tear openability of the packaging bag using this non-stretched polypropylene. is there. As will be described later, a packaging bag using the unstretched polypropylene and having the shape shown in the figure has conventionally been difficult to tear in the opening direction of the bag. That is, unstretched polypropylene exhibits relatively strong tear resistance in the opening direction.

In the illustrated embodiment, the heat-sealing layer 11 is provided with a vapor-deposited layer 12 of aluminum on the unstretched polypropylene. The vapor-deposited layer 12 imparts a gas barrier property against oxygen, water vapor, and the like, a light-shielding property, or a design property based on metallic luster to the packaging material 1, and is provided as necessary.

The tearable sheet 13 improves the tearability of the packaging bag 9, and a material that can be easily torn along the opening direction of the bag is selected. Aluminum foil is a preferred material because it is easy to tear in any direction. Moreover, you may use the plastic film which is easy to tear in the said opening direction.

Considering the manufacturing process of the pillow type packaging bag having the shape shown in FIG. 1, when a plastic film is used for the tearable sheet, the material is a so-called lateral tearable film. Is preferred.

That is, in order to manufacture a packaging bag having the shape shown in the drawing, a long film is prepared, and the both ends in the width direction are formed into a tubular shape so that the both ends are heat-sealed. To form a back-attached seal portion. Next, a seal is applied in a direction that traverses the back-applied seal portion of the tubular packaging material, and one of the portions to be the opening of the packaging bag is closed. Then, the packaging bag is obtained by cutting at a predetermined position. The contents are generally filled from the famous opening in the packaging bag and then the opening is closed, but the manufacturing process of the packaging bag and the filling process of the contents are combined. Sometimes. As described above, when the packaging bag having the illustrated shape is produced, it is general that the longitudinal direction of the back-sticking seal portion and the longitudinal direction of the packaging material for producing the same are the same. The plastic film that constitutes the packaging material, including the unstretched polypropylene of the heat seal layer, is generally capable of tearing in the longitudinal direction, but is difficult to tear in the direction orthogonal thereto. Therefore, it is preferable to use the transversely tearable film, which is specifically made so as to be easy to tear in the direction perpendicular to the longitudinal direction of the film.

The illustrated packaging material 1 is a laminate of the above materials with adhesives 17 and 18. Dry laminating is generally used as a method for laminating each material, but the present invention is not limited to this, and a laminating method using a solventless adhesive or a sand laminating method using a molten thermo-adhesive resin as an adhesive layer instead of using an adhesive is used. Means such as may be adopted.

The packaging material 1 thus obtained is slit into a predetermined width, if necessary, and then wound into a roll for use in a packaging bag manufacturing (bag making) step.

The shape of the packaging bag of the present invention may be, in addition to the shape shown in FIG. 1, a gusset pillow bag having folding portions 6 on both sides as shown in the explanatory view of FIG. 4, for example. With this shape, a relatively thick content can be easily stored. Further, by attaching a reinforcing material of an appropriate size, for example, thick paper, to a part of the folded portion, the shape retention of the packaging bag can be improved and the content protection can be improved. . In addition, the packaging bag of the present invention,
Further, known tearing assisting means such as perforations may be added if necessary.

<Example 1> 2 having a thickness of 12 μm as an outer layer
Prepare an axially stretched polyethylene terephthalate film,
Urethane-based ink (made by Toyo Ink Mfg. Co., Ltd., product name: LP Super) on one side (inner side) of this film
Was used to provide a printed layer of the pattern. After that, a predetermined position on the surface opposite to the printing surface (only the part corresponding to the back-stick seal part:
A scratch process was applied to a strip-shaped film having a width of about 8 mm from the end in the width direction. As a method of scratching, a method of pressing a roll in which diamond powder is embedded is adopted, and the depth of scratches is set to be 6 to 12 μm on average from about half of the thickness of the film to the depth of penetrating the film. .

Next, a urethane adhesive (Takelac A601 manufactured by Takeda Pharmaceutical Co., Ltd.) was applied to the printed surface of the polyethylene terephthalate film at an application amount of about 2 g / m ² , and a lateral direction of 18 μm in thickness was applied. A tearable high-density polyethylene film (manufactured by Toyo Kagaku Co., Ltd., trade name: Kararyan Y) was laminated. Further, a 25 μm-thick unstretched polypropylene film (manufactured by Toyo Metallizing Co., Ltd.) in which a lateral vapor-depositable high-density polyethylene film surface was previously provided with an aluminum vapor deposition layer having a thickness of 400 to 500 Å by the same adhesive as above. Product name: 2
203) was laminated. The obtained laminated body has a predetermined width (about 13
2 mm) was slit to obtain the packaging material of the present invention.

Using this packaging material, a gusset pillow bag shown in FIG. 4 was prepared. That is, with the heat-sealing layer of the packaging material as the inner surface side, both ends in the width direction are faced to each other and heat-sealed to form a back-sealed seal portion (seal width: about 10 m
m) was formed into a tubular shape, and both sides thereof were folded while being folded in such a manner that the back-adhered seal portion was located at substantially the center to obtain a flat tubular body having a folded portion. The width of the flat tubular body is about 40 mm, and the width of the folded portion is about 8 mm.

Next, a height of about 3 is passed across the back-sticking seal portion.
A 0 mm top seal was provided. In this way, if the top seal portion is provided with a certain height, a hanging hole can be provided in this portion to carry out hanging exhibition and sale.

Here, by forming the seal bar into a specific shape, the top seal part has about 5 parts on the content storage part side.
A protruding seal portion (width: about 5 mm) protruding to a height of mm is provided, and the protruding seal portion further has an I notch (length) which extends in the direction crossing the back-sealed seal portion and penetrates the heat seal layer. About 3 mm).

Then, the tubular body was cut into a length of about 210 mm with the top seal portion as a boundary, and a packaging bag (gazette pillow bag) of the present invention in which one side was opened was obtained.

About 30 g of bar-shaped chocolate confectionery was filled into the packaging bag from the opening, and then the opening was opened to about 5 m.
Heat sealing was performed at a width of m to form a bottom sealing portion, and the packaging bag was sealed.

When this packaging bag was torn and opened in the width direction of the bag with the I notch provided in the protruding seal portion as a trigger, it was possible to smoothly tear and open.

Example 2 An aluminum foil having a thickness of 7 μm was used in place of the laterally tearable high-density polyethylene film, and an ordinary non-stretched polypropylene film (thickness: A packaging material was obtained in the same manner as in Example 1 except that a product having a size of 25 μm and a product name: TAF502C manufactured by Tohcello Co., Ltd. was used. In addition, at the time of printing on the biaxially stretched polyethylene terephthalate film, perforation processing was performed at the planned opening position. Using this packaging material, Example 1
A gusset pillow bag having a shape similar to that shown in FIG. 4 was obtained.
This packaging bag was also torn and opened easily from the I-notch.

[0037]

EFFECTS OF THE INVENTION Since the packaging material of the present invention has the above-mentioned constitution, an unstretched polypropylene film which is excellent in oil resistance, taste retention or heat resistance, but is not easily torn in the width direction is used for the heat seal layer. Even if
It was possible to provide a pillow type packaging bag that is easy to tear.

[Brief description of drawings]

FIG. 1 is an explanatory plan view showing an embodiment of a packaging bag of the present invention.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a cross-sectional view showing an example of a packaging material forming the packaging bag of the present invention.

FIG. 4 is an explanatory view showing another embodiment of the packaging bag of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Packaging material 11 ... Heat-sealing layer 13 ... Tearable sheet 14 ... Outer layer 2 ... Back sticking seal part 31 ... Top seal part 32 ... Bottom seal part 4 ... Protrusion seal part 5 ... Notch 6 ... Fold part 9 ... Packing bag C ... Tearing direction S ... Scratch processing part

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Koshi Teramoto, 4-6-5, Utashima, Nishiyodogawa-ku, Osaka-shi, Osaka Ezaki Glico Co., Ltd.

Claims (8)

[Claims] 1. A pillow comprising a packaging material having a heat-sealing layer made of non-stretched polypropylene, which is formed into a tubular shape by back-sealing both ends in the width direction and sealing portions for closing openings at both ends of the tubular body. A packaging bag of the type, wherein at least one of the sealing parts that closes the opening is provided with a protruding seal part that protrudes toward the contents storage part, and the protruding seal part faces in a direction that crosses the back-sealed seal part. A packaging bag that is easy to open, characterized by having a cut that reaches the heat seal layer. 2. The tearable direction of the heat seal layer is
The packaging bag according to claim 1, wherein the packaging bag is parallel to the back-sealed seal portion. 3. The packaging material according to claim 1, wherein the packaging material includes an outer layer made of a stretched film, and at least a portion of the outer layer corresponding to the back-sticking seal portion is finely scratched. The stated packaging bag. 4. The packaging bag according to claim 1, wherein an aluminum vapor deposition layer is provided on the surface of the heat seal layer opposite to the heat seal surface. 5. The packaging bag according to claim 1, wherein the packaging material includes a tearable sheet that is easily torn in a direction crossing the back-sealed seal portion. 6. The packaging bag according to claim 5, wherein the tearable sheet is a lateral tearable high density polyethylene. 7. The packaging bag according to claim 5, wherein the tearable sheet is an aluminum foil. 8. A gusset pillow type packaging bag having folds on both sides of the bag.
The packaging bag according to claim 7.