JP2011225228A - Packaging bag - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a packaging bag for making the surface of a product packaging frozen food to be hardly frosted when transported for circulation or when sold at stores, thus preventing a printed pattern or indication from being hidden.SOLUTION: The packaging bag comprises a stack comprising at least a surface base material, an intermediate base material, and a sealant layer stacked in that order. An unbonded area where the surface base material and the intermediate base material are not bonded to each other is provided. An uneven layer is provided between the surface base material and the intermediate base material at least in the unbonded area.

Description

  The present invention relates to a packaging bag. In particular, it relates to a packaging bag for frozen food.

  Conventionally, as a packaging material constituting a plastic film packaging bag for storing frozen food, for example, a biaxially stretched polypropylene is used for the front substrate, and a non-stretched polypropylene is laminated as the sealant layer, or the same as the front substrate However, there was a packaging bag in which an aluminum-deposited low-density polyethylene film was bonded to the sealant layer.

  In addition, it is flexible even at low temperatures, and has excellent resistance to pinholes due to bending and friction caused by vibration during transportation and handling at stores, packaging bags using stretched nylon film for the surface base material and intermediate layer, Packaging bags using linear low density polyethylene for the sealant layer have also been used for frozen foods.

  In these packaging bags, the surface of the packaging bag is frosted at the time of distribution and transportation or at the store sales, and it may be difficult to see the design of the product or the printing of the display.

  To reduce this, it is conceivable to use a double wall so that the temperature of the packaged food is not directly transmitted. As a double-walled packaging bag, there is a packaging bag in which a pocket is provided in a packaging bag with another base material, although the use is different.

This is a packaging in which at least one surface of the packaging bag has the same size as the packaging bag in the left-right direction, a surface material with a short vertical dimension is arranged, and the upper end edge side of the front substrate is a pocket that opens. It is a bag. (Patent Document 1)
Known documents are shown below.

JP 2008-2104013 A

  When the above-mentioned packaging bag is used for packaging frozen food, frost adhesion may be prevented, but the bag making process is complicated and the cost increases. In addition, when products packed with frozen foods are packed in a packaging bag and transported / stored, the bag body and the front surface of the pocket may come into close contact with each other, reducing the frost prevention effect or breaking the pocket. is there.

  Furthermore, when a product with frost is distributed, water drops that have fallen after the frost has melted may be frozen again in the pocket. There is also a risk that when the consumer boils, hot water enters the pocket and burns when removed.

  An object of the present invention is to provide a packaging bag in which the surface of a product in which frozen food is packaged is not easily frosted during distribution and transportation, store sales, or the like, and the printed pattern or display is not invisible.

The present invention has been made in view of the problem, and the invention of claim 1 is a packaging bag comprising a laminate in which at least a surface base material, an intermediate base material, and a sealant layer are sequentially laminated,
A non-bonded region where the surface base material and the intermediate base material are not bonded is provided, and an uneven layer is provided at least between the surface base material and the intermediate base material in the non-bonded region. This is a packaging bag.

  The packaging bag of the present invention has the above-described configuration, and since the uneven layer is provided between the surface base material and the intermediate base material in the non-adhered region, the surface base material and the intermediate base in the non-adhesive region. Since it does not adhere to the material and the temperature of the directly packaged food is not transmitted, frost is hardly formed on the surface.

  The invention according to claim 2 of the present invention is the packaging bag according to claim 1, wherein the difference in height of the unevenness of the uneven layer is in the range of 3 to 15 μm.

  Furthermore, in the present invention, since the difference in height of the unevenness of the uneven layer is in the range of 3 to 15 μm, sufficient heat insulation is obtained and frost is hardly formed on the surface.

  Invention of Claim 3 of this invention is the packaging bag of Claim 1 or 2 with which the unevenness | corrugation of the said uneven | corrugated layer is formed by the uncoated part and coating part of a coating agent. is there.

  Moreover, since the unevenness | corrugation of an uneven | corrugated layer is formed of the uncoated part and coated part of a coating agent, an uneven | corrugated layer can be provided reliably reliably using a printing technique.

  Invention of Claim 4 of this invention is provided with the pattern of the said uncoated part of the said uneven | corrugated layer, and the said coated part by the dot pattern or the lattice pattern, The Claim 1 thru | or 3 characterized by the above-mentioned. It is a packaging bag given in any 1 paragraph.

  By providing in the above pattern, the heat insulation effect is obtained uniformly and it becomes difficult to occur that frost forms partially.

  The invention according to claim 5 of the present invention is the packaging bag according to any one of claims 1 to 4, wherein at least one of the front substrate and the intermediate substrate is a nylon film.

  Because nylon film is used, it does not become hard even at low temperatures, and is resistant to friction and bending, and can avoid bag breakage and pinholes.

  The invention of claim 6 of the present invention is the packaging bag according to any one of claims 1 to 5, wherein the contents of the packaging bag are frozen food.

  Even if the contents are frozen food, frost does not form at the time of distribution transportation or store sales, and the display can be seen.

  Since the packaging bag of the present invention is configured as described above, it is difficult for frost to be formed on the surface at the time of distribution and transportation or at the time of store sales.

It is explanatory drawing which showed typically an example of the packaging bag of this invention with the plane. It is explanatory drawing which showed typically the layer structure of an example of the packaging bag of this invention in the cross section. It is explanatory drawing which showed typically the layer structure of the other example of the packaging bag of this invention in the cross section.

  Hereinafter, modes for carrying out the present invention will be described. FIG. 1 is an explanatory view schematically showing an example of the packaging bag 1 of the present invention in a plan view.

  The packaging bag 1 of this example is composed of two laminated bodies, and is overlapped so that the sealant layers 10 are in contact with each other, and is sealed by the seal portion 2 at the peripheral portion. An unbonded region 3 in which the surface base material 4 and the intermediate base material 7 are not bonded is provided inside the seal portion 2, and the surface base material 4 and the intermediate base material 7 in the non-bonded region 3 are provided. Is provided with an uneven layer 8.

  The unbonded region 3 may be provided including the seal portion 2 or may be provided up to the seal portion 2. However, if the seal is thin, it is easy to break the bag. .

FIG. 2 is an explanatory view schematically showing in cross section the layer structure of an example of the packaging bag 1 of the present invention.
A pattern printing layer 5 is provided on the back side of the front substrate 4. The pattern printing layer 5 is bonded to the intermediate base material 7 by a partial adhesive layer 6 provided partially.

  The portion where the partial adhesive layer 6 is not provided is the non-adhesive region 3, and the uneven layer 8 is provided in contact with the pattern printing layer 5 in the non-adhesive region 3. And the uneven | corrugated layer 8 prevents adhesion | attachment of the pattern printing layer 5 and the intermediate base material 7, and is maintaining space. The intermediate base material 7 is further bonded to the sealant layer 10 via the adhesive layer 9.

  The manufacturing method of this example will be described below.

  Using a printing in-line dry laminator, the pattern printing layer 5 is printed on the back of the front substrate 4, the uneven layer 8 is formed in the unit after the printing machine, the coating portion of the coating agent is convex, and the uncoated portion is applied. With the process part as a recess, it is provided by printing, and the dry laminating adhesive is registered with the pattern of the pattern printing layer 5 in the same manner as gravure printing, and applied in a pattern to areas other than the unbonded area 3 Then, the intermediate substrate 7 is bonded.

  Thereafter, the sealant layer 10 is bonded to the surface of the intermediate substrate 7 via the adhesive layer 9. The adhesive layer 9 may be an adhesive for dry lamination, or may be a resin layer in an extrusion laminating method in which a molten resin is extruded from a T-shaped die. Further, the sealant layer 10 itself may be provided by an extrusion laminating method.

  The laminate prepared as described above is sealed on three sides with a bag making machine, and a three-side sealed bag is created by cutting or punching.

Next, another example of the packaging bag 1 of the present invention will be described below.
FIG. 3 is an explanatory view schematically showing in cross section the layer structure of another example of the packaging bag 1 of the present invention.

  A pattern printing layer 5 is provided on the back side of the front substrate 4. The pattern printing layer 5 is bonded to the intermediate base material 7 by a partial adhesive layer 6 provided partially.

An uneven layer 8 is provided on the surface of the intermediate substrate 7 on the front substrate 4 side, and the partial adhesive layer 6 covers the uneven layer 8 in the bonding area, and the pattern printing layer 5 of the surface substrate 4 and the intermediate substrate 7 is adhered. The portion where the partial adhesive layer 6 is not provided is the non-adhered region 3, and the space is maintained in the non-adhered region 3 so that the concave-convex layer 8 is not in close contact with the pattern printing layer 5 and the intermediate substrate 7. The intermediate base material 7 is further bonded to the sealant layer 10 via the adhesive layer 9.
The manufacturing method of this example will be described below.

  The concavo-convex layer 8 is previously provided on the intermediate base material 7 by using a gravure plate with the coated portion of the coating agent as a convex portion and the uncoated portion as a concave portion. At this time, the uneven layer 8 may be applied to the entire surface of the intermediate substrate 7.

  Using a printing inline dry laminator, print the pattern printing layer 5 on the back of the front substrate 4 and use the same method as gravure printing for the dry laminate adhesive in the unit after the printing machine. 5 is registered, an adhesive is applied in a pattern to a region other than the non-bonded region 3, and is bonded to the uneven layer 8 side of the intermediate substrate 7.

  Thereafter, the sealant layer 10 is bonded to the surface of the intermediate substrate 7 via the adhesive layer 9. The adhesive layer 9 may be an adhesive for dry lamination, or may be a resin layer in an extrusion laminating method in which a molten resin is extruded from a T-shaped die. Further, the sealant layer 10 itself may be provided by an extrusion laminating method.

  By the above, the laminated body used for the packaging bag 1 of the other example of this invention is made. In addition, after providing the uneven | corrugated layer 8 in the intermediate base material 7 beforehand, the sealant layer 10 is provided in the opposite surface, the surface by the side of the uneven | corrugated layer 8 of the intermediate base material 7, and the pattern printing of the surface base material 4 The surfaces may be bonded together via the partial adhesive layer 6.

  The laminate prepared as described above is sealed on the three sides with a bag making machine, and a three-side sealed bag is created by cutting or punching to obtain the packaging bag 1 of the present invention.

  In the above description, the three-way seal bag has been described. However, the present invention is not necessarily limited to the three-way seal bag. A pillow bag with a back seal may be used, one film may be folded and overlapped, the other two sides sealed and the remaining one open, or a folded film on the bottom A standing pouch or a gusset bag provided with a gusset portion may be used.

  As the front substrate 4 used in the present invention, a biaxially stretched resin such as nylon, polyethylene terephthalate, or polypropylene, or a uniaxially stretched or unstretched plastic film can be preferably used. In this case, the thickness is about 12 to 30 μm.

  Similarly, as the intermediate base material 7 used in the present invention, a biaxially stretched plastic film of a resin such as nylon, polyethylene terephthalate, or polypropylene can be preferably used. In this case, the thickness is about 6 to 30 μm.

  It is desirable to use a nylon film for at least one of the front substrate 4 and the intermediate substrate 7. By using a nylon film, a packaging bag 1 that is difficult to break even when frozen can be obtained. Moreover, sufficient heat resistance is obtained even when the bag is boiled before eating.

  Moreover, as the surface base material 4, it is preferable to use a biaxially-stretched polypropylene film because it is strong. As a result, the unevenness of the uneven layer 8 is less likely to appear on the surface of the packaging bag 1, the appearance is preferable, and the space created by the unevenness is firmly maintained.

  Therefore, a combination using a biaxially stretched polypropylene film for the front substrate 4 and a nylon film for the intermediate substrate 7 is most suitable.

  For the sealant layer 10, a heat-meltable resin is used. Polypropylene, low density polyethylene, linear low density polyethylene, acid-modified polyethylene, or the like is used. In particular, linear low density polyethylene is preferably used from the viewpoints of low temperature sealing properties and flexibility during freezing.

  The sealant layer 10 may be previously laminated as a film on the intermediate layer via the adhesive layer 9 or may be provided by an extrusion laminating method.

  The printing method for providing the pattern printing layer 5 is not particularly limited, but gravure printing or flexographic printing is usually used. Further, foil stamping or the like may be performed.

  The partial adhesive layer 6 may be formed by applying an adhesive only to a necessary portion using an adhesive for dry lamination and a gravure plate. The adhesive is selected from adhesives for dry lamination in consideration of adhesiveness to each substrate, but a two-component curable urethane adhesive is preferably used.

  The concavo-convex layer 8 can be provided by a printing method with the coated portion of the coating agent as a convex portion and the uncoated portion as a concave portion. The coating agent is not particularly limited as long as there is no problem in adhesiveness. An overprint varnish, a medium, or the like may be used, but a matte varnish in which inorganic or organic fine particles are dispersed in a resin component, or a foamed ink that is foamed during heat drying after coating is preferably used.

  It is desirable that the difference in height of the unevenness of the uneven layer 8 is in the range of 3 to 15 μm. If it is lower than 3 μm, frost may be formed on the surface of the packaging bag due to cold air from the inside. On the other hand, when the thickness is higher than 15 μm, the post-processing suitability is deteriorated, for example, the winding shape is deteriorated due to the overlapping of the concave and convex portions, and the winding is deviated.

  The pattern of the coating part of the coating agent of the concavo-convex layer 8 and the uncoated part may be provided with a dot-like coating part or a grid-like coating part on one side. The shape of the dot may be a round shape or an oval shape, or may be a polygon such as a triangle, a rectangle, or a hexagon. Moreover, it is not specifically limited, such as a star shape and a crescent moon shape.

  Similar to the partial adhesive layer 6, the adhesive layer 9 may be formed by using only an adhesive for dry lamination and a gravure plate so that only a necessary part of the adhesive is applied. The adhesive is selected from adhesives for dry lamination in consideration of adhesiveness to each substrate, but a two-component curable urethane adhesive is preferably used.

  Further, the adhesive layer 9 may be provided by an extrusion laminating method in which a molten resin is extruded from a T-shaped die. As the hot-melt resin, low-density polyethylene is often used, but other hot-melt resins such as modified polyethylene may be used.

  Further, when the sealant layer 10 itself is provided by an extrusion laminating method, it may be bonded to the intermediate substrate 7 using an anchor coating agent. When the intermediate substrate 7 is a resin similar to the resin of the sealant layer 10, the adhesive layer 9 can be omitted.

Specific examples of the present invention will be described below.
<Example 1>
A biaxially stretched polypropylene having a thickness of 20 μm is prepared as the front substrate 4, and a pattern printing layer 5 by gravure printing is provided on this corona-treated surface using a gravure printing inline dry laminating machine, and the uneven layer 8 is further gravure-coated. In the final unit of the printing section of the printing inline dry laminating machine, printing was provided using foam varnish instead of ink.

  As the foam varnish, W211 New Die Form (registered trademark) manufactured by Dainichi Seika Kogyo Co., Ltd. was used. This foaming varnish is obtained by dispersing foamed microcapsules in an ethylene vinyl acetate resin, and has a foaming ratio of 8 to 9 times.

  The plate on which the foam varnish was applied was a plate in which a pattern in which 1 mm circular dots were arranged in a staggered manner at intervals of 3 mm came to the unbonded region 3 as shown in FIG. The difference in the height of the unevenness of the uneven layer 8 thus provided was 12 μm.

  Next, a two-component curing type for dry laminating using a gravure plate that is made so that the adhesive comes to the adhesion area other than the non-adhesion area 3 in the dry laminator section installed in the gravure inline dry laminating machine A urethane adhesive is applied to the adhesive region of the surface printed surface 5 of the base substrate 4 to provide a partial adhesive layer 6, and a 15 μm double-sided corona-treated biaxially stretched nylon film to be the intermediate substrate 7 is bonded. It was.

Furthermore, using another dry laminating machine on the opposite surface of this biaxially stretched nylon film, a two-component curable urethane adhesive for dry lamination of the adhesive layer 9 was applied, and a linear low density polyethylene having a thickness of 70 μm. And a sealant layer 10 was provided to obtain a laminate. Using this laminate, a three-side sealed bag (dimensions: length 150 mm, width 120 mm) was produced, and the packaging bag 1 of Example 1 was obtained.
<Example 2>
A matte varnish was used in place of the foamed varnish used for printing the concavo-convex layer 8, and the plate on which the matte varnish was applied was changed to a grid pattern with a line width of 2 mm and an interval of 5 mm. The packaging bag 1 of Example 2 was obtained.

  The mat varnish used was NB300 Soft Suede (registered trademark) OP varnish manufactured by Dainichi Seika Kogyo Co., Ltd. This mat varnish is obtained by dispersing acrylic beads having a particle diameter of 5 μm in urethane vinyl chloride. Further, the height difference of the unevenness of the uneven layer 8 provided thereby was 7 μm.

Hereinafter, comparative examples of the present invention will be described.
<Comparative Example 1>
Implementation was performed except that the uneven layer 8 was not provided, and an adhesive was applied to the entire surface of the pattern print layer 5 of the front substrate 4 to adhere the intermediate substrate 7 and not provide the partial adhesive layer 6. In the same manner as in Example 1, a packaging bag of Comparative Example 1 was obtained.
<Evaluation method>
The packaging bags of Examples 1 and 2 and Comparative Example 1 produced as described above were filled with hamburger with sauce, the opening was sealed to form a package, and frozen. After freezing, the package was returned to a room temperature environment and the surface was observed.

  As a result of the observation, a sample in which frost adhered to the surface of the packaging bag was evaluated as bad and evaluated as x, and a sample in which frost was not adhered to the surface of the packaging bag was evaluated as good. The results are shown in Table 1.

＜比較結果＞
実施例１及び２は、室温の環境に戻しても、包装袋の表面に霜が付かず、絵柄や表示の印刷がはっきり見えたが、比較例１は、包装袋の表面に霜が付いて、絵柄や表示の印刷がよく見えなかった。特に一括表示欄の文字は読み取ることが出来ないほどであった。

<Comparison result>
Even if Example 1 and 2 returned to the environment of room temperature, frost did not adhere to the surface of a packaging bag, and the printing of a pattern and a display was seen clearly, but Comparative Example 1 has frost on the surface of a packaging bag. , I couldn't see the print of the pattern and display well. In particular, the characters in the batch display column could not be read.

DESCRIPTION OF SYMBOLS 1 ... Packaging bag 2 ... Seal part 3 ... Non-adhesion area | region 4 ... Front base material 5 ... Pattern printing layer 6 ... Partial adhesion layer 7 ... Intermediate base material 8 ... -Uneven layer 9 ... adhesive layer 10 ... sealant layer

Claims (6)

At least a packaging bag comprising a laminate in which a front substrate, an intermediate substrate, and a sealant layer are sequentially laminated,
A non-bonded region where the surface base material and the intermediate base material are not bonded is provided, and an uneven layer is provided at least between the surface base material and the intermediate base material in the non-bonded region. A packaging bag characterized by that.   The packaging bag according to claim 1, wherein the difference in height of the unevenness of the uneven layer is in the range of 3 to 15 μm.   The packaging bag according to claim 1 or 2, wherein the unevenness of the uneven layer is formed by an uncoated part and a coated part of the coating agent.   The packaging bag according to any one of claims 1 to 3, wherein a pattern of the uncoated portion and the coated portion of the uneven layer is provided in a dot pattern or a lattice pattern.   The packaging bag according to any one of claims 1 to 4, wherein at least one of the front substrate and the intermediate substrate is a nylon film.   The packaging bag according to any one of claims 1 to 5, wherein the contents of the packaging bag are frozen food.

Images