JP3084083B2 - Packaging goods - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a packaged article in which a package to be sterilized by heat is stored in a composite film bag which is sealed with a top seal, an end seal and a center seal.

[0002]

2. Description of the Related Art In recent years, foods, such as LL noodles, which have been packaged in a plastic composite film, sterilized by heating for 30 minutes or more with steam or hot water at 90 ° C. or more, and which can be stored at room temperature for a long period of time (usually 5 months) have been sold. ing. Such packaged articles of foods to be sterilized by heating are generally configured to be housed in a bag in which a nylon / polyethylene dry laminate film is sealed on four sides.

[0003]

However, in such a conventional packaged article, when subjected to heat sterilization under normal pressure, a small amount of air remaining in the bag expands during the heat treatment and the internal pressure of the bag increases. A large pressure was applied to the seal portion and the like, and peeling and leaking occurred in the seal portion, and the device did not have the performance to withstand the heat treatment.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted intensive studies to overcome such disadvantages, and as a result, have reached the present invention.

The present invention uses a composite film having at least a three-layer structure in which a sealing layer made of a polyolefin resin is laminated on at least one surface of a polyamide film with an adhesive resin layer interposed therebetween, using a top seal, an end seal, and a center. The present invention relates to a packaged article in which an article to be packaged is stored by a seal.

The polyamide film according to the present invention is not particularly limited, and may be nylon 6, nylon 66, nylon 6
10. Polyamide resin such as nylon 12 or nylon 6
Examples thereof include copolyamides such as 66 copolymer, nylon 6-610 copolymer, and the like, aromatic polyamides, amorphous polyamides, and the like. There is no particular limitation.

The adhesive resin is not particularly limited as long as it can bond the polyamide film and the polyolefin resin layer. Specifically, an ethylene-propylene copolymer is used. Examples thereof include a propylene-butene copolymer, a modified polyolefin-based resin, and an ionomer resin, and more preferably a resin having a Vicat softening point of 95 ° C. or higher.

As the modified polyolefin-based resin, an unsaturated carboxylic acid such as maleic acid, fumaric acid, acrylic acid, or an acid anhydride, an ester or a metal salt derivative is copolymerized with an olefin alone or a copolymer, for example, by grafting. The polymerized modified polymer can be exemplified as a typical example.
The modified polyolefin resin alone or in a mixture with other components such as a polyolefin resin is also included in the modified polyolefin resin. At this time, as the olefin-based resin, high-, medium-, low-density polyethylene, linear low-density polyethylene, ethylene-propylene copolymer, ethylene-
Examples thereof include an ethyl-acrylate copolymer and an ethylene-vinyl acetate copolymer.

The polyolefin resin constituting the seal layer is not particularly limited as long as it is a polyolefin resin. Polyethylene of various densities (including linear low-density polyethylene), polypropylene, polybutene, ethylene-propylene having a low density to a high density is included. Copolymer, ethylene-propylene-
Butene terpolymers, ionomer resins, ethylene-acrylic acid copolymers, ethylene-ethyl-acrylate copolymers, ethylene-vinyl acetate copolymers, the modified polyolefin-based resins described above, etc. Those having a softening point in the range of 100 to 115 ° C can be more preferably exemplified.

In the composite film according to the present invention, the polyolefin resin constituting the seal layer has a Vicat softening point of 100.
-115 ° C., and the Vicat softening point of the adhesive resin for bonding the polyamide film and the polyolefin resin layer is 95 ° C. or more, and it is desirable to composite by co-extrusion, but it is not necessarily limited to this, and depending on the application. May be outside this range.

Vicat softening point of polyolefin resin 1
If the Vicat softening point of the adhesive resin is less than 95 ° C. even at a temperature of 00 to 115 ° C., the packaged article tends to cause delamination, leakage, peeling of a seal portion, etc., which is not preferable in many cases. Even if the Vicat softening point of the adhesive resin is out of the above range and the Vicat softening point of the adhesive resin is 95 ° C. or higher, delamination, leakage, and peeling of the seal portion are likely to occur, which is not preferable in many cases.

In short, according to the present invention, the polyolefin resin constituting the seal layer has a Vicat softening point of 100 to 115.
° C, and the Vicat softening point of the adhesive resin for bonding the polyamide film and the seal layer made of the polyolefin resin layer is 95 ° C or higher, and the temperature of steam or hot water is 90 ° C or higher if coextruded. , Processing time 3
Even when subjected to heat sterilization for 0 minutes or more, the delamination phenomenon, leak, peeling off of the seal portion, etc. do not occur, which is effective for food packaging products requiring heat sterilization, but not necessarily the above-mentioned. It is not limited to the range of the Vicat softening point, and depending on the application, it can be used even if it does not exceed the Vicat softening point of the polyolefin resin layer of 100 to 115 ° C and / or the Vicat softening point of the adhesive resin of 95 ° C or more.

Heat sterilization means that foods, especially raw noodles,
Heat treatment in steam or hot water of 0 ° C. or more can be exemplified for 30 minutes or more, but is not necessarily limited thereto.
Other heat treatment, for example, long-time treatment with hot water of 90 ° C. or lower, short-time treatment (within 30 minutes) at 90 ° C. or higher, or retort sterilization may be used, and the treatment method is not particularly limited.

In order to produce the packaged article of the present invention, the composite film 1 wound into a roll is subjected to a center seal (vertical seal) by a center seal heater 2 so that the seal layer is on the inner surface, and is formed into a cylindrical body. At the same time, an end seal (horizontal seal) is applied by the end seal heater 3, preferably, the packaged object is stored from the upper packaged product storage port 6, and the top seal and the end seal of the next bag are simultaneously performed by the top seal heater 4. It is preferable to use a vertical pillow type packaging machine that performs automatic packaging continuously while cutting the boundary 5 between the top seal and the end seal, but is not necessarily limited thereto.

The flat composite film is formed into a long composite film by slitting it in an appropriate width according to the shape, weight, etc. of the article to be packaged, and then the sealing layer of the long composite film is formed on the inner surface. And both ends are envelope type 8 or Gassho type 1
0, the center seals 8 and 10 are performed, a cylindrical body is formed in advance, and when packaging an object to be packaged, the bag is cut to an appropriate length and subjected to the end seal 9 or the top seal 7 to form a bag. A method in which the article to be packaged is stored later and the top seal 7 or the end seal 9 is performed, or a three-sided seal type bag in which the seal layers of two flat composite films face each other and both ends and the lower part are heat-sealed, or For example, there is a method in which an object to be packaged is stored in a square-seal type bag or a bag formed by forming a tube-shaped composite film into a bag, and a top seal or an end seal is performed. The packaging method is not particularly limited.

Next, a method for forming a composite film constituting the packaged article of the present invention will be described. However, the content of this description is merely an example, and the method for forming a film is not limited thereto.

[0017] At least three extruders are connected to the multilayer coextrusion die, one is a polyamide resin (A), the other is an adhesive resin (B), and the other is a polyolefin resin. (C) is supplied, fed into a flat multilayer die heated by a screw while being heated and melted, and laminated in a heating die to form a flat molten laminate by coextrusion. Then, it is cooled and solidified by a suitable cooling device to form a flat laminated film, and two to five times longitudinal stretching is performed in the longitudinal direction with two pairs of rolls having different peripheral speeds and a heating roll (100 to 150 ° C.). Lateral stretching is performed 2 to 6 times at 100 to 200 ° C. while holding both ends in a tenter. At this time, if necessary, 190-90
A method for forming a composite film that is heat-set at 250 ° C. for 2 to 6 seconds and then wound into a roll is exemplified, but is not limited thereto.

The composite polyethylene film is formed into a composite film by extrusion lamination, dry lamination, thermocompression bonding, or the like, and the polyolefin resin (C) is bonded to the polyamide film (A) via the adhesive resin (B). Alternatively, a biaxial, multiaxial, uniaxial stretching film forming method by simultaneous stretching method or the like, or a co-extruded tubular film formed by an annular multilayer die and simultaneous biaxial stretching to form a composite film can be exemplified.

The structure of the composite film is not particularly limited.
C / B / A / B / C or the like having / B / C or A as an intermediate layer is exemplified, but a resin layer of the same type (C ′) or a different type (D) may be further laminated on the C layer. A / B / C / C ', A / B / C
/ D, D / C / B / A / B / C / D etc. A configuration in which the A layer is an intermediate layer is preferable, but is not necessarily limited thereto. Furthermore, at least the surface may be subjected to corona discharge treatment, printing, coating, or the like, and is not particularly limited.

To the layers A, B and C, other kinds of resins, stabilizers, lubricants, UV inhibitors, antistatic agents, anti-fogging agents, pigments, fillers, etc. are added as long as the performance is not impaired. There is no particular limitation.

The thickness configuration may be appropriately determined depending on the packaged article, and is not particularly limited. Normal total thickness 40-100
μ can be exemplified.

The packaged article of the present invention is not particularly limited, and is not limited to foods to be subjected to heat sterilization (for example, noodles for LL), foods to be retorted, containers for which heat sterilization is required. Labels, cap seals, lids, and the like can be exemplified.

Hereinafter, the present invention will be described with reference to examples.

【Example】

Nylon 6
(A), maleic acid-modified polyethylene resin (Vicat softening point 100 ° C) in two extruders with a barrel inner diameter of 40φ
(B) A flat co-extruded multilayer in which a linear low-density polyethylene resin (Vicat softening point of 110 ° C.) (C) is supplied to two other extruders having an inner diameter of 40 mm and heated and melted and heated to 250 ° C. by a screw. The mixture was fed into a die, laminated in the die, and co-extruded to obtain a molten laminate. Next, it is cooled and solidified by a chill roll (30 ° C.) in which cooling water circulates, heated to 80 ° C. between a slow (front) drive roll and a fast (rear) drive roll, stretched three times in the longitudinal direction, and entered into a tenter at both ends. Hold 1
Lateral stretching was performed three times at 20 ° C. Subsequently, a heat treatment was performed at 210 ° C. for 10 seconds while holding both ends in the tenter rear chamber, and C / B / A / B / C = 14/2/9/23/23 μm.
(Total thickness 50μ) and C / B / A / B / C = 15/2/1
A composite film of 0/2 / 25μ (total thickness 55μ) was obtained.

The above composite film is 20 cm long and 30 cm wide.
Then, the heat-sealing layer (C) was cut into an inner surface, and the both ends in the vertical direction were overlapped with the thicker side of the heat-sealing layer (C) as the inner surface. At this time, the seal was an impulse seal having a seal width of 2.4 mm.

Next, about 200 g of fresh noodles were stored in the bag, one upper part of the bag was intentionally wrinkled, pressed lightly to release air, and then top-sealed to obtain a packaged article.

This packaged article is heated at 98-99 ° C. with hot steam for 30 minutes.
After heat-treated for a minute and allowed to cool, tearing of the seal portion, lamination peeling, seal peeling, and the like were examined. Table 1 shows the results.

[0028]

Comparative Example 1 Comparative Example 1 In the examples, a maleic acid-modified polyethylene resin (B) was used as a modified polyethylene resin having a vigat softening point of 90 ° C, and a linear low density polyethylene resin (C) was used as a vicat softening point of 95 ° C. Replaced with linear low-density polyethylene resin,
C / B / A / B / C = 15/2 / by the same method as in the embodiment.
A composite film of 10/2 / 25μ (total thickness 55μ) was obtained. Next, the packaged article in which the raw noodles were packaged in the same manner as in the example was subjected to heat sterilization treatment under the same conditions as in the example, and the sealing portion was examined for tearing, lamination peeling and seal peeling, and the results are shown in Table 1.

Comparative Example 2 In the examples, a maleic acid-modified polyethylene resin (B) was used as a modified polyethylene resin having a Vicat softening point of 100 ° C., and a linear low density polyethylene resin (C) was used as a line having a Vicat softening point of 120 ° C. C / B / A / B / C = 15 /
A composite film of 2/10/2/25 (total thickness 55 μ) was obtained. Next, the packaged product in which the raw noodles were packaged was heat-sterilized under the same conditions as in the example, and the lamination peeling of the seal portion and the peeling of the seal were examined, and the results are shown in Table 1.

[0030]

[Table 1]

As is clear from Table 1, even when the packaged article of the present invention is subjected to a heat sterilization treatment (98 ° C. to 99 ° C., 30 minutes), the seal portion is broken, the lamination peeling, and the heat seal peeling occur. The non-defective rate was 100%. On the other hand, the Vicat softening point of the adhesive resin (maleic acid-modified polyethylene resin) of 90 ° C. and the Vicat softening point of the polyolefin resin (linear low-density polyethylene resin) of 95 ° C. both show the Vicat softening point according to the present invention. Comparative Example-1 out of range
And the polyolefin resin (linear low-density polyethylene resin) has a Vicat softening point of 120 ° C., and only the polyolefin resin deviates from the Vicat softening point range according to the present invention. %, 60%
And was inferior to the examples. Further, the packaged article of the present invention was prepared using a vertical pillow packaging machine, but the suitability for the packaging machine was also good.

[0032]

As described above, the present invention provides a co-extruded composite film in which a polyamide film is laminated with a polyolefin resin having a Vicat softening point of 100 to 115 ° C via an adhesive resin having a Vicat softening point of 95 ° C or more. The present invention relates to a packaged article in which an article to be packaged is stored using a top seal, an end seal, and a center seal.

Even if the packaged article of the present invention is subjected to heat sterilization at 90 ° C. or more for 30 minutes or more, film breakage, which has often been a problem in conventional packaged articles made by dry lamination,
It did not cause lamination peeling or peeling of the seal portion, and was particularly suitable for packaging foods such as raw noodles.

The packaged article of the present invention can be applied not only to foods but also to containers requiring heat sterilization and retort sterilized products.

[Brief description of the drawings]

FIG. 1 is a schematic view of a vertical pillow packaging machine according to the present invention.

FIG. 2 is a perspective view of a bag in which the composite film according to the present invention is formed into an envelope.

FIG. 3 is a perspective view of a bag in which the composite film according to the present invention is formed in a central gasket seal shape.

[Description of sign]

 DESCRIPTION OF SYMBOLS 1 Composite film 2 Center seal heater 3 End seal heater 4 Top seal heater 5 Cutter 6 Stored article storage port 7 Top seal 8 Center seal with envelope 9 End seal 10 Center seal with joint palm

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-2-293141 (JP, A) Japanese Utility Model Showa 59-162237 (JP, U) Japanese Utility Model Showa 60-177054 (JP, U) (58) Field (Int.Cl. ⁷ , DB name) B65D 75/28 B65D 81/24

Claims (2)

(57) [Claims] 1. Linear low-density polyethylene resin layer (Vicat softening point of resin: 100 to 115 ° C.) / Modified polyolefin adhesive resin layer (Vicat softening point of resin: 95 ° C. or higher)
/ Polyamide-based film / Modified polyolefin-based adhesive resin layer (Vicat softening point of resin 95 ° C or higher) / Linear low-density polyethylene-based resin layer (Vicat softening point of resin 100 to
A packaged article capable of being subjected to a heat sterilization treatment under normal pressure, comprising a co-extruded biaxially stretched film composed of five layers (115 ° C.) and containing an article to be packaged by a top seal, an end seal, and a center seal. 2. The packaged article according to claim 1, wherein the polyamide film comprises a nylon 6 resin.