JP4060632B2 - Breathable bag - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a bag having air permeability suitable for a rice bag or the like that can easily deaerate air enclosed inside when filling the contents.
[0002]
[Prior art]
Conventionally, as a breathable bag used as a rice bag or the like, two square-shaped laminated films having thermal adhesiveness are overlapped, and a breathable heat composed of a thermal adhesive part and a non-thermal adhesive part on two opposing sides. A bag having a configuration in which an adhesive portion is formed and air inside the bag is discharged from the non-thermally bonded portion of the formed breathable thermal adhesive portion to be deaerated is known. However, in the case of the bag having this configuration, the laminated films are in close contact with each other at the non-thermally bonded portion, so that there is a disadvantage that a gap is not easily formed between the two laminated films and the internal air is not easily deaerated. In addition, when the non-thermally bonded portion is enlarged, the deaeration property is improved, but there is a disadvantage that contents such as rice stored inside leak out.
[0003]
As a packaging bag with the above drawbacks improved, for example, as described in JP 2000-190992 A, a sheet is formed by laminating two sheet materials and adhering peripheral edges, and In a bag in which a part of the peripheral part of each sheet material is not bonded and a small hole for air venting is formed, fine unevenness by embossing on at least one of the joining surfaces in the non-bonded part of the peripheral part of the two sheet materials There is known a packaging bag having a shape. However, in the above packaging bag, since the unevenness formed on at least one of the joining surfaces in the unbonded portion of the peripheral portion of the two sheet materials is a fine unevenness, there is a gap formed between the two sheet materials. It has a defect that it becomes a fine gap and an excellent deaeration property cannot be obtained.
[0004]
[Problems to be solved by the invention]
An object of the present invention is to provide a breathable bag for packaging rice and the like, which has good deaeration of air enclosed in the bag and can prevent the entry of pests and the like from the outside and the penetration of water. It is to be.
[0005]
[Means for Solving the Problems]
A bag made of a laminated film of two rectangular front and back surfaces having a base material layer and a heat-adhesive resin layer and formed by a peripheral heat-bonding portion, wherein at least one side of the peripheral heat-bonding portion is a non-thermal bonding portion A breathable heat-bonded portion made of a heat-bonded portion is formed, and only one point-like protrusion protruding toward the inner surface is formed on one laminated film only in the region of the non-heat-bonded portion of the breathable heat-bonded portion , By leaving the inner surface side of the laminated film flat without forming point-like protrusions, two sheets are formed by the point-like protrusions protruding toward the inner surface side formed on the one laminated film in the non-thermal adhesive portion. Through the gap formed between the laminated films, the air enclosed inside is degassed when filling the contents, thereby projecting to the inner surface side formed in the laminated film at the non-thermal adhesive portion. To point-like projections Since a gap corresponding to the height of the dot-like projections is formed between the two laminated films, air sealed inside the bag was formed between the two laminated films when filling the contents. It can be easily deaerated through the gap.
[0006]
In the above-described breathable bag, by adopting a configuration in which the dot-like projections are formed so as to straddle the inner end of the breathable thermal bonding portion, the breathable thermal bonding is performed even when the bag is filled with contents and inflated. Since the gap is formed without the two laminated films being in close contact with each other along the inner end of the part, deaeration is facilitated.
[0007]
In the above-described air-permeable bag, the dot-like protrusions have a diameter of 1.5 to 4.0 mm, a height of 0.1 to 0.8 mm, and a length of the non-thermally bonded portion of 3.0 to 5. By setting it as 0 mm, since the clearance gap corresponding to the height of a dotted | punctate protrusion can be formed between two laminated films by a dotted | punctate protrusion in a non-thermal-bonding part, the outstanding deaeration property is obtained.
[0008]
In the above-described breathable bag, an extended portion having a certain width is formed outside the breathable thermal bonding portion, so that two laminated films on the front and back sides of the extending portion outside the breathable thermal bonding portion. As a result, the pests and the like can be prevented from entering from the outside, and water can be prevented from penetrating into the bag even when wet.
[0009]
In the breathable bag, the laminated film is formed by embossing using a male mold comprising a cylindrical projection and a female mold comprising a cylindrical hole, so that the laminated film has excellent shape retention and shape. Therefore, a gap corresponding to the height of the dot protrusion can be reliably formed between the two laminated films.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a plan view showing a first embodiment of the present invention, FIG. 2 is an enlarged sectional view taken along line II in FIG. 1, FIG. 3 is a plan view showing a second embodiment of the present invention, and FIG. FIG. 5 is a cross-sectional view showing a method of forming point-like protrusions on a laminated film, FIG. 6 is a cross-sectional view of the laminated film on which point-like protrusions are formed, and 2 is a peripheral thermal bonding , 3 is a breathable thermal bonding part, 3a is a thermal bonding part, 3b is a non-thermal bonding part, 4 is a dot-like projection, 5 is an extension part, 6 is a male type, 6a is a cylindrical projection, 7 is a female type 7a are cylindrical holes, and 11 and 12 are laminated films.
[0011]
1st Embodiment of the air permeable bag of this invention is as showing in FIG. 1, FIG. As shown in FIG. 1, the planar shape is formed by superimposing the heat-adhesive resin layer surfaces of the two laminated films 11, 12 on the front and back sides having a base layer and a heat-adhesive resin layer, and opposing long sides. Peripheral heat bonding part 2 is formed on two sides consisting of the above, and breathable thermal bonding part 3 consisting of thermal bonding part 3a and non-thermal bonding part 3b is formed on one of the opposing short sides. In the non-thermal bonding part 3b, one point-like projection 4 protruding to the inner surface side is formed on one laminated film 11 so as to be located at the center of the non-thermal bonding part 3b, and on the outside of the breathable thermal bonding part 3 In this configuration, the extending portions 5 of the laminated films 11 and 12 having a certain width are formed.
[0012]
The cross-sectional shape in the direction parallel to the longitudinal direction of the breathable thermal bonding portion 3 where the point-like protrusions 4 of the first embodiment are formed is as shown in FIG. 2 and is one point-like shape protruding toward the inner surface side. In a state where the laminated film 11 with the protrusions 4 formed and the laminated film 12 without the dot-like protrusions 4 are superposed, the breathable thermal bonding part 3 composed of the thermal bonding part 3a and the non-thermal bonding part 3b is formed. It is the structure formed so that the dotted | punctate protrusion 4 may be located in the center of the non-thermal-bonding part 3b, and the inner surface side formed in the laminated film 11 between the two laminated films 11 and 12 of the front and back in the non-thermal-bonding part 3b A gap corresponding to the height of the point-like protrusion 4 is formed by the point-like protrusion 4 protruding in the direction. In the first embodiment, since the sharply shaped point-like protrusions 4 having excellent shape retention properties, a gap corresponding to the height of the point-like protrusions 4 is reliably formed between the two laminated films 11 and 12. Excellent degassing properties can be obtained. In addition, the extended portion 5 of the laminated films 11 and 12 having a certain width is formed outside the breathable thermal bonding portion 3, and the laminated films 11 and 12 are overlapped at the extended portion 5. Since the gap formed by the protrusions 4 is closed, it is possible to prevent the entry of insects and the like from the outside, and also prevent water from penetrating into the bag even when wet. It can be done. The width of the extension 5 is preferably 3 to 15 mm.
[0013]
The top view of 2nd Embodiment of the air permeable bag of this invention is as showing in FIG. Compared with the first embodiment, the position where the dot-like protrusions 4 are formed is formed so as to straddle the inner end of the breathable thermal bonding portion 3 in the non-thermal bonding portion 3b of the breathable thermal bonding portion 3. The configuration is the same except for differences. In the second embodiment, even when the air-permeable bag is filled with the contents and inflated, the dot-like projections 4 are formed so as to straddle the inner end of the air-permeable thermal bonding portion 3. Since the two laminated films 11, 12 do not adhere to each other at the inner end of the portion 3, a gap is formed by the dot-like projections 4, so that the air enclosed in the breathable bag is in the breathable heat bonding portion 3. Since it becomes easy to flow out from the non-thermally bonded portion 3b through the gap formed along the inner end, the deaeration property is excellent. Although not shown, the cross-sectional configuration of the portion where the spot-like protrusions 4 are formed in the non-thermal bonding part 3b is a point-like shape between the two laminated films 11 and 12 on the front and back sides in the non-thermal bonding part 3b, as in the first embodiment. Since a gap corresponding to the height of the protrusion 4 is formed, excellent deaeration is obtained. In the first and second embodiments, the extending portions 5 of the laminated films 11 and 12 having a certain width are formed outside the breathable thermal bonding portion 3, but the extending portions 5 are not formed. You can also
[0014]
As shown in FIG. 4, the planar shape of the third embodiment of the breathable bag of the present invention is the thermal bonding of the two laminated films 11 and 12 having a square shape composed of a base material layer and a thermal adhesive resin layer. The peripheral heat-bonding portion 2 is formed on the short side and the breathable heat-bonding portion 3 including the bonding portion 3a and the non-thermal bonding portion 3b is formed on the two opposite long sides. Then, in the non-thermal bonding part 3b of the breathable thermal bonding part 3, one point-like projection 4 is formed on one laminated film 11 so as to straddle the inner end of the breathable thermal bonding part 3. Also in the third embodiment, the same excellent deaeration performance as in the second embodiment can be obtained. In the third embodiment, the point-like protrusion 4 is formed so as to be positioned at the center of the non-thermally bonded part 3b of the breathable thermally bonded part 3, and the non-thermally bonded part 3b is formed on one of the opposing long sides. A configuration in which a breathable thermal bonding portion 3 having one dot-like protrusion 4 is formed, and a configuration in which an extension portion 5 of a laminated film 11 and 12 having a certain width is formed outside the breathable thermal bonding portion 3. You can also
[0015]
In 1st-3rd embodiment, as a shape of the dotted | punctate protrusion 4 formed in the laminated | multilayer film 11, a diameter is 1.5-4.0 mm and height is 0.1-0.8 mm. . The length of the non-thermally bonded portion 3b that forms the point-like protrusion 4 is preferably 3.0 to 5.0 mm. If the diameter of the point-like protrusion 4 is larger than 4.0 mm, it becomes difficult to form a sharp point-like protrusion 4 and the shape-retaining property of the point-like protrusion 4 is deteriorated, so that a gap is surely formed between the two laminated films. It becomes difficult to form, and when the diameter of the point-like protrusion 4 is smaller than 1.5 mm, it becomes difficult to form the sharp point-like protrusion 4. Since the height of the dot-like projection 4 is 0.1 to 0.8 mm, a gap corresponding to the height of the dot-like projection 4 can be reliably formed between the two laminated films.
[0016]
In order to form the dot-shaped protrusions 4 on the laminated film 11, a male mold 6 having a cylindrical protrusion 6a having a round tip and a female mold 7 having a cylindrical hole 7a as shown in FIG. The laminated film 11 is formed with the pointed protrusions 4 having a sharp shape and having excellent shape-retaining properties, as shown in FIG. 11 can be produced. The embossing using the male mold 6 and the female mold 7 is preferably performed at room temperature, so that the workability of the embossing can be improved.
[0017]
In order to form the breathable heat-bonding portion 3, the dotted film 4 faces the laminated film 12 side in the laminated film 11 formed with the dot-like protrusions 4 and the laminated film 12 where the dot-like protrusions 4 are not formed as shown in FIG. By using a hot plate having a heating portion corresponding to the thermal bonding portion 3a and a non-heating portion corresponding to the non-thermal bonding portion 3b, the dotted protrusions 4 correspond to the non-heating portion of the hot plate. Thus, by hot pressing between the hot plate and the base plate, the heat bonded portion 3a is formed by the heated portion of the hot plate, and the non-heat bonded portion 3b is formed by the non-heated portion of the hot plate, thereby non-thermal bonding The breathable thermal bonding part 3 having the point-like protrusions 4 on the part 3b can be formed.
[0018]
As the base material layer constituting the laminated films 11 and 12, biaxially stretched biaxially stretched polyethylene terephthalate (PET), biaxially stretched nylon (ON), metal-deposited biaxially stretched polyethylene terephthalate (VMPET), etc. A stretched film, linear low density polyethylene (LLDPE), etc. can be used. As the heat adhesive resin layer, low density polyethylene (LDPE), linear low density polyethylene (LLDPE), ethylene-vinyl acetate copolymer (EVA), or the like can be used. The base material layer and the heat-adhesive resin layer are laminated by dry lamination (DL) using a urethane-based adhesive or extrusion lamination (EC) using polyethylene or the like. Since the breathable bag of the present invention is used for packaging rice and the like, it is necessary to be a bag excellent in strength, and linear low-density polyethylene is used as the resin constituting the heat-adhesive resin layer. It is preferable to do this. By using VMPET as the base material layer, a breathable bag with excellent design can be obtained.
[0019]
As a structure of the laminated film, for example, ON 15 μm / DL / LLDPE 50-80 μm, ON 15 μm / EC 15-25 μm / LLDPE 30-70 μm, PET 12 μm / EC15-25 μm / LLDPE 40-60 μm, LLDPE30-40 μm / DL / LLDPE 40-50 μm, LLDPE 60 μm / EC25 μm ON15 μm / DL / VMPET 12 μm / DL / LLDPE 40 to 60 μm, ON15 μm / DL / VMPET 12 μm / EC15 to 25 μm / LLDPE 30 to 60 μm, PET12 μm / DL / VMPET 12 μm / EC15 to 25 μm / LLDPE 40 to 60 μm, and the like.
[0020]
【The invention's effect】
A bag made of a laminated film of two rectangular front and back layers having a base material layer and a heat-adhesive resin layer and formed by a peripheral heat-bonding portion, wherein at least one peripheral heat-bonding portion is a non-thermal bonding portion and a heat It is a breathable heat-bonded part composed of an adhesive part, and projects to the inner surface side of one laminated film in the non-thermally bonded part of the breathable heat-bonded part. By having a configuration in which one point-like protrusion of ~ 0.8 mm is formed, the point-like protrusion protruding on the inner surface side formed on the laminated film in the non-thermal adhesive portion causes a point between the two laminated films. Since a gap corresponding to the height of the protrusion is formed, the air enclosed in the bag can be easily deaerated through the gap formed between the two laminated films when filling the contents. it can.
[0021]
In the above-described breathable bag, by adopting a configuration in which the dot-like projections are formed so as to straddle the inner end of the breathable thermal bonding portion, the breathable thermal bonding is performed even when the bag is filled with contents and inflated. Since the two laminated films do not adhere to each other along the inner end of the portion and a gap is formed, the deaeration property can be improved.
[Brief description of the drawings]
FIG. 1 is a plan view showing a first embodiment of the present invention.
FIG. 2 is an enlarged cross-sectional view taken along line II in FIG.
FIG. 3 is a plan view showing a second embodiment of the present invention.
FIG. 4 is a plan view showing a third embodiment of the present invention.
FIG. 5 is a cross-sectional view showing a method for forming point-like protrusions on a laminated film. FIG. 6 is a cross-sectional view of a laminated film on which point-like protrusions are formed.
[Explanation of symbols]
2 Peripheral thermal bonding part 6a Cylindrical protrusion 3 Breathable thermal bonding part 7 Female
3a Thermal bonding part 7a Cylindrical hole
3b Non-thermal bonding part 11, 12 Laminated film 4 Dot protrusion 5 Extension part 6 Male

Claims (5)

A bag made of a laminated film of two rectangular front and back surfaces having a base material layer and a heat-adhesive resin layer and formed by a peripheral heat-bonding portion, wherein at least one side of the peripheral heat-bonding portion is a non-thermal bonding portion A breathable heat-bonded portion made of a heat-bonded portion is formed, and only one point-like protrusion protruding toward the inner surface is formed on one laminated film only in the region of the non-heat-bonded portion of the breathable heat-bonded portion , By leaving the inner surface side of the laminated film flat without forming point-like protrusions, two sheets are formed by the point-like protrusions protruding toward the inner surface side formed on the one laminated film in the non-thermal adhesive portion. The air-permeable bag is characterized in that the air enclosed therein is degassed through the gap formed between the laminated films .   The breathable bag according to claim 1, wherein the dot-like projections are formed so as to straddle an inner end of the breathable thermal bonding portion.   The point-like protrusions have a diameter of 1.5 to 4.0 mm, a height of 0.1 to 0.8 mm, and a length of the non-thermally bonded portion of 3.0 to 5.0 mm. The breathable bag according to claim 1 or 2.   The breathable bag according to any one of claims 1 to 3, wherein an extending portion having a constant width is formed outside the breathable thermal bonding portion.   The breathable bag according to any one of claims 1 to 4, wherein the point-like protrusions are formed by embossing using a male mold having a cylindrical protrusion and a female mold having a cylindrical hole. .

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