JPH10218201A - Packaging bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enable contents to be easily taken out by providing an unsealing cut as a start point for tearing in parallel to a base of the triangular corner at a portion corresponding to a region to be opened on a heat seal on one of sides of the triangular corner. SOLUTION: A packaging bag 3 is made of a laminate material including a resin film having straight cuttability at least in one direction, and further an unsealing cut 5 as a start point for tearing is provided on a heat seal 21 of one of sides of a triangular corner at M corresponding to a region to be opened. A direction X1 of straight cuttability of the film constituting the laminate material, a linear direction X2 of a base 4 of the triangular corner 1 and an unsealing direction X3 of a notch line of an unsealing notch constituting the unsealing cut 5 are desirably in a parallel relation, whereby a cut of the opening can be formed straight and correctly.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a packaging bag,
More specifically, the present invention relates to a packaging bag which is suitable for filling and packaging of foods and beverages, etc., and which can easily and easily open a packaged product.

[0002]

2. Description of the Related Art Various types of packaging bags have been developed and proposed for filling and packaging foods and beverages and the like. One of them is a packaging bag having a form having a triangular corner, such as a home base type. This one usually has a triangular shape at the corners as the tip,
An opening cut portion as a tearing start point is formed in a heat seal portion at a tip end portion of the heat seal portion corresponding to the opening opening area, and both sides of the opening cut portion are manually formed. , The bag is torn to form an opening and opened, and the contents are taken out. by the way,
As shown in FIG. 4, the opening cut portion is usually a triangular tip portion P constituting the packaging bag 21 and a heat seal portion 22 corresponding to a region to be opened. Using a knife, a cutter or the like, an opening cut portion 23 such as a V-shaped notch, a U-shaped notch, or an I-shaped notch is formed in the direction of the arrow indicated by the dotted line Q in the above direction. Attention is paid to the fact that the bag is torn and opened at the portion where the opening cut portion 23 is torn as a starting point for tearing and engraving the heat seal portion 22 at right angles. Writing and the like are printed and displayed.

[0003]

However, in the above-mentioned packaging bag, there are various problems in forming the opening cut portion. First, when opening,
Normally, holding the part where the cut part for opening is engraved, and trying to open the bag by pulling the bag body left and right (up and down), it is difficult to open it straight and accurately. In fact, the cut of the opening is bent obliquely during opening, and it is extremely difficult to form a desired opening. Further, when opening the bag, it is usually easy to open the bag by holding the bag in a hand and pulling strongly, and in such a case, if the contents are liquid, the opening cut portion is opened. There is a problem that a cut of the opening is formed as a point, and the contents are pushed out of the cut vigorously to unintentionally stain hands, clothes, and the like. Therefore, when opening, scissors, knife,
Some people try to open using tools such as cutters,
Even if it is for business use, in the case of home use, these tools are not always close to you, and it is extremely inconvenient to open them.In addition, use tools etc. even for business use Opening after that is time-consuming, and the workability is inferior. Therefore, the present invention provides a packaging bag having a triangular corner portion, which is very easily and accurately opened without using a tool or the like, and the contents are easily taken out. It is to provide a packaging bag that can be.

[0004]

As a result of various studies to solve the above problems, the present inventor has at least one or more triangular corners and the peripheral end thereof has In a packaging bag surrounded by a heat seal portion, the packaging bag is formed of a laminated material including a resin film having a straight-cutting property in at least one direction, and further includes the above triangular corners. A heat-sealing portion on one side of the corner is provided with an opening cut portion as a starting point of tearing in parallel with the triangular base of the above-mentioned corner at a position corresponding to the opening area. In this case, the direction of the straight cutability of the resin film, the cutout line of the opening cutout portion constituting the opening cutout portion, and the triangular base of the corner portion are , Manufacturing packaging bags in a substantially parallel relationship,
Then, the contents are filled and packed in the packaging bag, and when the package is opened, the above-mentioned cut portion for opening is torn to the left and right (up and down), and without using any tools. ,
With the opening cut portion as the opening start point, the opening is cut straight and accurately, and the opening can be easily opened without shifting the opening line of the opening. The present invention has been completed by finding a packaging bag from which a can be taken out.

That is, the present invention relates to a packaging bag having at least one or more triangular corners and a peripheral end surrounded by a heat seal portion. A heat-sealing portion on one side of the corner portion, and a cut portion for opening as a starting point of tearing, in a position corresponding to the expected opening area, in parallel with the triangular base of the corner portion. And a packaging bag.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below. The packaging bag according to the present invention will be described with reference to the drawings by exemplifying a few examples. FIGS. 1, 2 and 3 show a few examples of the configuration of the packaging bag according to the present invention. FIG. 4 is a plan view showing a configuration of a packaging bag according to a conventional example.

First, as an example of a packaging bag according to the present invention, as shown in FIG. 1, as shown in FIG. 1, at least one triangular corner 1 is provided, and a peripheral end thereof is a crown. Packaging bag 3 surrounded by seal portions 2, 2, etc.
In the above, the packaging bag 3 is composed of a laminated material including a resin film having a straight cut property in at least one direction,
Furthermore, heat of one side of the corner portion 1 of the shaped aforementioned triangular - city - a le 2 _1, portions corresponding to the opening region where M
A packaging bag A having a configuration in which, for example, an opening cut portion 5 made of, for example, an I-shaped notch is provided as a starting point of tearing in parallel with the triangular base 4 of the corner 1 described above. it can. Thus, as shown in FIG. 1, in the packaging bag A according to the present invention, a direction X ₁ of a straight cut property of a resin film having a straight cut property in at least one direction constituting the laminated material, The straight direction X ₂ of the triangular base 4 of the corner 1 and the cutout 5 for opening
Opening direction X of the notch line of the opening notch portion constituting
₃ is desirably in a substantially parallel relationship, whereby the opening cut portion 5 is torn as a tearing starting point, thereby forming a straight and accurately cut edge of the opening. Without shifting the opening line of
This has the advantage that it can be easily opened.

Next, the packaging bag according to the present invention will be described.
As shown in FIG. 2, as another example of the packaging bag B having another form, as the opening cut portion, instead of the opening cut portion formed of the I-shaped notch as described above, for example, a V-shaped notch is used. well even opening for cutting portions 5 ₁ comprising, by Thus, in this case, as shown in FIG. 2, straight of the resin film having at least one direction straight cuttability during lamination material forming the packaging bag a direction X ₁ of the cutting property, the linear direction X ₂ of the triangular base 4 above the corners 1, cut the opening notches unit consisting of the V-shaped notch constituting the opening for the cutting portion 5 ₁ of the Either _{one of} the notch lines L ₁ and L _{2 is} a notch line L ₂ (in this case, the notch line L ₂ )
The unsealing direction X _3, and it is desirable in the generally parallel relationship, thereby, by tearing the opening for cutting portion 5 ₁ as a starting point tear, straight, correctly, to form a cut of the opening Further, there is an advantage that the opening can be easily opened without shifting the opening line of the opening. In FIG. 2, reference numerals 1, 2, 3, 4, M, etc. have the same meanings as in FIG.

[0009] Further, the packaging bag according to the present invention,
As shown in FIG. 3, as another example of the packaging bag C having another form, as the opening cut portion, instead of the opening cut portion formed of the I-type notch or the V-type notch as described above, for example, well even opening for cutting unit 5 ₂ consisting of U-shaped notch, and Thus, in this case, as shown in FIG. 3, a resin having at least one direction straight cuttability during lamination material forming the packaging bag between the direction X ₁ of the straight cut of the film, the linear direction X ₂ of the triangular base 4 of the above-described corner portion 1, the opening for cutting consisting of U-shaped notch constituting the opening for the cutting portion 5 ₂ of the Notch lines L ₁ , L at the notch
One either ₂ cut-line L ₁ (in this case, the cut-line L ₁₎ and the unsealing direction X _3, and it is desirable in the generally parallel relationship, thereby opening a cut portion 5 By tearing ₂ as the starting point of tearing, straightly and accurately form a cut of the opening,
This has the advantage that the opening can be easily opened without shifting the opening line of the opening. Incidentally, in FIG.
Symbols such as 1, 2, 3, 4, and M have the same meaning as in FIG. 1 described above.

The above examples illustrate only a few examples of the packaging bag according to the present invention, and the present invention is not limited thereto. For example, although not shown, the form of the packaging bag is a home base as described above.
Instead of a pentagonal shape such as a square shape, a packaging bag having a shape such as a triangle, a hexagon, or an octagon may be used.

Next, in the present invention, in the above-mentioned packaging bag, an opening cut portion is engraved on at least one side of a heat seal portion constituting a triangular corner. The packaging bag according to the present invention can be manufactured.
In the above description, as a method of forming the opening cut portion, for example, it can be engraved using a usual cutter, knife, emboss plate or emboss roll, or the like.
In the present invention, the shape of the cut portion for opening may be any cut shape such as a simple straight cut line, a perforated cut line, a V-shaped notch, a U-shaped notch, a UV notch, or an I-shaped notch.

A method for filling and packaging the contents of the packaging bag according to the present invention as described above will be described.
An opening is formed on one side of the sealing portion, the contents are filled and packaged from the opening, and then the opening is heat-sealed to form a heat-sealing portion. Filled and packaged products can be manufactured. Thus, in order to remove the contents of the above-mentioned packaged product, hold the opening cut portion in the hand and tear it left or right or up and down. Thus, as described above, in the packaging bag according to the present invention, the direction of the straight cut of the resin film having the straight cut in at least one direction constituting the laminated material, The straight line direction of the triangular base at the corner of the opening and the opening direction of the notch line of the opening notch portion constituting the above-described opening cut portion are positioned in a substantially parallel relationship, so that the opening cut is performed. When the portion is torn as a tearing start point, the opening can be formed straight and accurately, and the opening can be easily opened without shifting the opening line of the opening.

Next, in the present invention, the materials constituting the above-described packaging bag according to the present invention and the manufacturing method thereof will be described. The packaging bag according to the present invention basically comprises at least Using a laminated material containing a resin film having a straight-cutting property in one direction, and making it into a bag,
Can be manufactured. Of course, in the present invention, a packaging bag according to the present invention can also be manufactured by using a laminated material containing a resin film having no straight-cutting property in at least one direction, and making this into a bag. By the way, as the base film constituting the above-mentioned laminated material, since this is a basic material constituting the packaging bag, mechanical, physical, chemical, etc. Sheets can be used, and specifically, for example, polyester resins, polyamide resins, polyaramid resins, polyethylene resins, polypropylene resins, polycarbonate resins, acrylic resins, A film or sheet of a tough resin such as a polyacetal resin, a fluorine resin, or the like can be used. Thus, as the resin film or sheet, any one of an unstretched film and a stretched film stretched in a uniaxial or biaxial direction can be used. In addition, in the present invention, the thickness of the resin film may be a thickness capable of maintaining strength, rigidity and the like to the minimum necessary, and is about 10 μm to 100 μm, preferably about 12 μm to 50 μm.
μm is most desirable.

Incidentally, the packaging bag according to the present invention is preferably manufactured by using a laminated material containing a resin film having a straight-cutting property in at least one direction, and manufacturing the laminated material. It is desirable that the material film be a resin film having a straight cutting property in at least one direction. Thus, as a resin film having a straight cutting property in at least one direction as described above,
As the base film exemplified above, a resin film stretched in a uniaxial direction, a biaxial direction, or the like can be used. Specifically, in the present invention, for example, a biaxially stretched special nylon film (trade name, “Uniathlon”) manufactured by Idemitsu Petrochemical Co., Ltd. is used as a resin film having a straight cut property in at least one direction. be able to. The above product name, "Uniathlon"
A resin film consisting of, having excellent straight cutability in the flow direction while maintaining excellent practical strength, which is a property of nylon resin, and having easy tearability,
Furthermore, it is an environmentally friendly barrier-free substrate containing no chlorine or the like.

Next, in the present invention, when the packaging bag according to the present invention is made, it is preferable to use at least the film of a heat-sealing resin as the innermost layer. Any heat-sealable resin film may be used as long as it can be melted by heat and fused together. For example, low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene , Ethylene-vinyl acetate copolymer, ionomer resin, ethylene-acrylic acid copolymer, ethylene-ethyl acrylate copolymer, ethylene-
Films or sheets of resins such as methacrylic acid copolymers, ethylene-propylene copolymers, methylpentene polymers, polybutene polymers, acid-modified polyolefin resins, and the like can be used. The thickness of the above resin film is about 10 μm to 300 μm, preferably about 20 μm to 100 μm.

Next, in the present invention, in addition to the above-mentioned materials, for example, if necessary, a material having a property of shielding light such as sunlight or a property of not transmitting water vapor, water, gas, etc. Which may be a single base material or a composite base material obtained by combining two or more base materials. Specifically, for example,
Aluminum foil having a light-shielding property and a barrier property, a resin film having a vapor-deposited film thereof, a silicon oxide film having a barrier property, a resin film having a vapor-deposited film of an inorganic oxide such as aluminum oxide, a barrier against water vapor, water, etc. Low-density polyethylene, medium-density polyethylene, high-density polyethylene, linear low-density polyethylene, polypropylene, a resin film or sheet such as an ethylene-propylene copolymer, and polyvinylidene chloride having gas barrier properties; Resin films or sheets such as polyvinyl alcohol, saponified ethylene-vinyl acetate copolymer,
Films or sheets of various colored resins having a light-shielding property obtained by adding a colorant such as a pigment to a resin, adding a desired additive, and kneading to form a film can be used. These materials can be used alone or in combination of two or more. The thickness of the above-mentioned film or sheet is arbitrary, but usually 5 μm to 3 μm.
It is preferably about 00 μm, more preferably about 10 μm to 100 μm. Further, in the above, the aluminum foil has a thickness of about 5 μm to 30 μm, and the aluminum or inorganic oxide deposited film has a thickness of about 1 μm to 30 μm.
Thousands of about $ 2000 to $ 2000 can be used. Examples of the resin film supporting the above-mentioned vapor-deposited film include a polyester film, a polyamide film, a polyolefin film, a polyvinyl chloride film, a polycarbonate film, a polyvinylidene chloride film, a polyvinyl alcohol film, and an ethylene-acetic acid film. Saponified vinyl copolymer films and the like can be used.

In the present invention, in addition to the above-mentioned materials, usually, packaging bags are subjected to severe conditions, both chemically and physically, when filling and packaging various articles. In many cases, in addition to the above-mentioned materials, a resin film or sheet constituting a normal flexible packaging bag can be used in the same manner. Polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, polypropylene, ethylene-propylene copolymer, ethylene-vinyl acetate copolymer, ionomer resin, ethylene-ethyl acrylate copolymer, ethylene-acrylic acid Or methacrylic acid copolymer, methylpentene polymer, polybutene resin, polyvinyl chloride resin, polyvinyl acetate resin, polyvinylidene chloride Fat, vinyl chloride-vinylidene chloride copolymer, poly (meth) acrylic resin, polyacrylonitrile resin, polystyrene resin, acrylonitrile-styrene copolymer (AS resin), acrylonitrile-butadiene-styrene copolymer ( ABS resin),
Polyester resin, polyamide resin, polycarbonate resin, polyvinyl alcohol resin, ethylene
Saponified vinyl acetate copolymer, fluorine-based resin, diene-based resin, polyacetal-based resin, polyurethane-based resin,
It can be arbitrarily selected from known resin films or sheets such as nitrocellulose and the like.
In addition, for example, a film such as cellophane, synthetic paper, or the like can be used. In the present invention, any of the above-mentioned resin films or sheets that have not been stretched or stretched uniaxially or biaxially can be used. The thickness is arbitrary, but is from several μm to 3 μm.
It can be used by selecting from a range of about 00 μm.
Furthermore, in the present invention, as the resin film or sheet, extrusion film formation, inflation film formation, and
Any property such as a thin film may be used.

Next, in the present invention, a method for producing a laminated material constituting the packaging bag according to the present invention by using the above-mentioned materials will be described. Lamination methods used when manufacturing materials, for example, wet lamination method, dry lamination method, solventless dry lamination method, extrusion lamination method, T-die co-extrusion molding method, co-extrusion lamination method -Inflation method, inflation method, etc. Thus, in the present invention, when performing the above lamination, if necessary, a pretreatment such as a corona treatment or an ozone treatment can be applied to the film. (Urethane-based), polyethyleneimine-based, polybutadiene-based, organic titanium-based anchor coating agents, or polyurethane-based, polyacryl-based, polyester-based,
A known anchor coating agent such as an epoxy-based, polyvinyl acetate-based, cellulose-based, or other laminating adhesive;
An adhesive or the like can be used.

By the way, in the above-mentioned method of manufacturing a laminated material, the extruded resin constituting the adhesive resin layer at the time of extruding and laminating is, for example, polyethylene,
Ethylene-α-olefin copolymer, polypropylene,
Copolymers of ethylene and unsaturated carboxylic acids such as polybutene, polyisobutene, polyisobutylene, polybutadiene, polyisoprene, ethylene-methacrylic acid copolymer, or ethylene-acrylic acid copolymer, or acid-modified polyolefins obtained by modifying them A series resin, an ethylene-ethyl acrylate copolymer, an ionomer resin, an ethylene-vinyl acetate copolymer, and the like can be used. Further, in the present invention, as the adhesive constituting the adhesive layer at the time of dry lamination, specifically,
Two-component curable urethane adhesives, polyester urethane adhesives, polyether urethane adhesives, acrylic adhesives, polyester adhesives, polyamide adhesives, polyvinyl acetate adhesives used in dry laminates, etc. An adhesive, an epoxy-based adhesive, a rubber-based adhesive, and the like can be used.

Next, in the present invention, a method for producing a packaging bag using the laminated material according to the present invention will be described. As such a method, there are various methods. The heat-sealing resin film layers are superposed face to face, and the peripheral edge is heat-sealed to provide a seal portion, thereby producing a packaging bag according to the present invention. be able to. In the above, as a form of heat sealing the peripheral end, for example, a side seal type,
Two-way seal type, three-way seal type, four-way seal type, envelope-attached seal type, gasket-attached seal type (pyro-seal type), pleated seal type, flat-bottomed seal Heat seal forms such as seal type, square bottom seal type, boat bottom seal type, etc.
Various forms of packaging bags suitable for this can be manufactured. In addition, for example, a self-supporting packaging bag (standing pouch) or the like can be manufactured. In the above, as a method of heat sealing, for example,
Roll, rotary roll seal, belt seal, impulse seal
It can be performed by a known method such as a seal, a high-frequency seal, an ultrasonic seal, or the like.

In the present invention, the packaging bag according to the present invention produced as described above can be used for filling and packaging various articles, for example, for filling and packaging articles such as food and drink and others. It is suitable.

[0022]

The present invention will be described more specifically with reference to the following examples. Example 1 After forming a desired printing pattern on the back surface of a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm by a gravure printing method, a 7-μm-thick aluminum foil was coated on the printing pattern surface with a two-component curable polyurethane. Dry laminating using a dry adhesive method using a system adhesive, and furthermore, applying a dry laminating method using a two-component curing type polyurethane adhesive on the surface of the aluminum foil as described above. 15 μm biaxially stretched nylon film
Then, a non-stretched polypropylene film having a thickness of 50 μm is dried on the surface of the biaxially stretched nylon film by a dry lamination method using a two-component curable polyurethane-based adhesive in the same manner as described above. Thus, a laminated material having the following layer configuration was manufactured. (Inner side) Thickness 50
Non-stretched polypropylene film of μm / adhesive layer / biaxially stretched nylon film of 15 μm thickness / adhesive layer / aluminum foil of 7 μm thickness / adhesive layer / biaxially stretched polyethylene terephthalate film of 12 μm thickness Using the laminated material produced above, a home base-type pentagonal front substrate and a back substrate are manufactured, and then the front and back substrates are unstretched polypropylene film. The surfaces are superimposed on each other, and then one side of the upper end is left, and the other peripheral end is heat-sealed. Further, one side of the heat seal forming a triangular tip portion is formed. An opening cut portion formed of an I-shaped notch was carved at the opening position in parallel with the bottom of the triangular tip, thereby producing a home-based packaging bag. Next, the contents were filled and packaged through the opening, and then the opening was heat-sealed to produce a packaged product. At the time of opening the packaged product, holding the above cut portion for opening and tearing it to the left and right,
Open the cut portion for opening as a tearing start point,
By tearing the bag body by holding it in hand, a cut edge of the opening could be formed straight without bending, and the contents could be taken out very easily.

Example 2 A desired printing pattern was formed on the back surface of a biaxially stretched polyethylene terephthalate film having a thickness of 12 μm by a gravure printing method, and two aluminum foils having a thickness of 7 μm were formed on the printing pattern surface. Dry laminating is performed by a dry laminating method using a curable polyurethane-based adhesive, and further, a dry laminating method is performed on the surface of the aluminum foil using a two-component curable polyurethane-based adhesive as described above. A 15 μm thick biaxially stretched special nylon film (trade name, “Uniathlon TB101” manufactured by Idemitsu Petrochemical Co., Ltd.)
0 "), and thereafter, the surface of the biaxially stretched special nylon film is dried by a dry lamination method using a two-component curable polyurethane adhesive in the same manner as described above to form a 50 μm thick non-woven sheet. The stretched polypropylene film was dry-laminated to produce a laminate having the following layer structure. (Inner side) Non-stretched polypropylene film having a thickness of 50 μm / adhesive layer / biaxially stretched special nylon film having a thickness of 15 μm / adhesive layer / aluminum foil having a thickness of 7 μm / adhesive layer / biaxially stretched having a thickness of 12 μm Polyethylene terephthalate film Next, a pentagonal front base material and a back base material of a home base type are manufactured by using the laminated material manufactured as described above. Are laminated with their unstretched polypropylene film surfaces facing each other, and then, one side of the upper end is left, and the other peripheral end is heat-sealed. An opening cut portion formed of a deformed V-shaped notch in one side of a heat seal portion constituting the front end portion of the heat seal portion and at the expected opening position in parallel with the bottom side of the triangular front end portion (see FIG. 2). Engraving
A home-based packaging bag was manufactured. Next, the contents are filled and packaged through the opening, and then the opening is sealed.
The packaged product was manufactured by tosealing. At the time of opening the packaged product, when the above-described opening cut portion was torn to the left and right with the hand, the opening was opened with the opening cut portion as a tearing start point, and further, the bag was held in the hand and the bag was torn. The cut of the opening could be formed straight without bending, and the contents could be taken out very easily.

[0024]

As is apparent from the above description, the present invention has at least one or more triangular corners and its peripheral end is surrounded by a heat seal. In the packaging bag, the packaging bag is formed of a laminated material including a resin film having a straight-cutting property in at least one direction, and furthermore, a heat sheet of one side of the above triangular corner is provided.
At the location corresponding to the opening scheduled area, in parallel with the triangular base of the corners, an opening cut portion as a starting point of tearing is provided. For packaging in which the direction of the straight-cutting property of the film, the cutout line of the opening cutout portion constituting the opening cutout portion, and the triangular base at the corner are substantially parallel to each other. A bag is manufactured, and the contents are filled and packed in the packing bag. When the bag is opened, the cut portion for opening is torn to the left and right (up and down) by hand, without using a tool. And, with the opening cut portion as the starting point of opening, the opening of the opening can be formed straight and accurately, and the opening can be easily opened without shifting the opening line of the opening. Can manufacture packaging bags from which objects can be taken out Is that.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of the configuration of a packaging bag according to the present invention.

FIG. 2 is a plan view showing an example of the configuration of the packaging bag according to the present invention.

FIG. 3 is a plan view showing an example of the configuration of the packaging bag according to the present invention.

FIG. 4 is a plan view showing a configuration of a packaging bag according to a conventional example.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Triangular corner part 2 Heat seal part 2 ₁ Heat seal part 3 Packaging bag 4 Triangular base 5 Opening cut part 5 ₁ Opening cut part 5 ₂ Opening cut part A Packaging Bag B Packaging bag C Packaging bag L ₁ , L ₂ Notch line of cutout for opening M Location corresponding to expected opening area X ₁ Straight cut property of resin film having linear cut property in _one direction Direction X ₂ Straight line direction of triangular base 4 at corner 1 X ₃ Opening direction of notch line of opening notch forming opening cut portion 5

Claims (7)

[Claims] 1. A packaging bag having at least one or more triangular corners and a peripheral end surrounded by a heat seal part, wherein the triangular corners are provided. A heat seal part on one side of the corner, which corresponds to the expected opening area, is parallel to the triangular base of the above-mentioned corner,
A packaging bag provided with an opening cut portion as a starting point of tearing. 2. The packaging bag according to claim 1, wherein the packaging bag has a square shape. 3. The packaging bag according to claim 1, wherein the packaging bag is a pentagonal home base type. 4. The packaging bag according to claim 1, wherein the packaging bag is made of a laminated material containing a resin film having a straight-cutting property in at least one direction. bag. 5. The opening cut-out portion comprising a V-shaped notch, a U-shaped notch or an I-shaped notch, wherein the opening cut portion is a notch for opening. Bags for packaging. 6. The packaging bag according to claim 5, wherein a notch line constituting the opening notch portion is engraved in parallel with a triangular base of the corner. . 7. A cutout line forming a cutout portion for opening, a direction in which a resin film is straightly cut, and a triangular base of a corner portion are parallel to each other. A packaging bag according to claim 6.