JPH03666A - Easy-to-open package and its manufacture - Google Patents

Abstract

PURPOSE:To improve sealing ability and easy-to-open ability by a method wherein the upper face of a flange of a package is structured to be specifically multi- layered and heat-sealed from the side of a lid with a heat-seal ring having uneven circles on the inner and outer peripheries to continuously form thin parts on the outer and inner circles. CONSTITUTION:A package 1 is formed with an innermost layer 4-2 having intensity between film layers of 2.5kg/15mm or higher and a layer 4-3 having interlayer strength of 0.3 to 2.0kg/15mm on the upper face of a flange 4-1. The flange of this package is heat-sealed from the side of a lid 2 with a ring 5 having a continuous uneven circles on the outer periphery 5-1 and the inner periphery 5-3. When the lid 2 is raised in a direction of arrow 6, a cut 7 is generated on the thin part 4-2 of a thin sealant layer formed by the outer peripheral uneven seal, and then the layer 4-2 is further cut to be unpacked while the layer 4-3 is cohesively broken.

Description

DETAILED DESCRIPTION OF THE INVENTION A1.Object of the invention (industrial application field) The present invention is an easy-to-open container package used in the industry of sealing and packaging foods, and a method for manufacturing the same. Specifically, in a package consisting of a lid and a container, after filling the container with contents,
The present invention relates to a container package that can be sealed with a lid by heat sealing and then opened by easily peeling off the heat sealed portion by hand when taking out the contents, and a method for manufacturing the same.

(Prior Art) Some conventional easy-open packages can be sealed by heat sealing and then opened with sufficient force by human hands.

For example, a so-called hot-melt adhesive is a mixture of ethylene-vinyl acetate copolymer plastic and an adhesion promoter such as rosin or polyterpene resin, or petroleum wax, or a so-called hot-melt adhesive is a mixture of ethylene-vinyl acetate copolymer plastic and an adhesion promoter such as rosin or polyterpene resin, or a so-called hot-melt adhesive is a mixture of ethylene-vinyl acetate copolymer plastic, rosin, polyterpene resin, etc. A so-called heat seal lacquer or the like, in which the composition is dissolved in an appropriate solvent, is applied to the lid base material and dried to form a film to be used as a lid material or container, such as polyvinyl chloride, borinitylene, polyester, polypropylene. , a sealed package with polycarbonate, etc., or an easily peelable sealant film made by extrusion laminating or film casting using extrusion casting equipment using a method commonly used in the industry, using a sealant resin designed to be peelable after heat sealing. , a container package in which a lid material bonded to a lid material base material is heat-sealed to a container made of each material by a dry lamination method using an adhesive.

The heat seal strength between the lid material and the container of these easy-to-open packages is 0.5, which is within the range that can be peeled off appropriately with the force of human hands.
kg/15mm to about 1.5kg/715mm, and is used as an easy-to-open container technology with a so-called interfacial peeling structure.

Furthermore, appropriately adjusting the lamination strength between the sealing layer and its adjacent layer in order to increase the heat sealing strength;
The so-called easy-to-open container technology with a peel-off structure that can withstand retort sterilization by making the seal layer easier to cut using a heat seal bar, or more specifically, a line seal bar, is also outdated. (It has been generalized since.

As an invention in the scope of easy-to-open container technology with a peel-off structure, Japanese Patent Application Laid-Open No. 63-30707 proposes that an annular convex portion is provided on the periphery of a heat seal bar to serve as both a surface seal and a line seal. No. 64-70374, etc.

However, these conventional easy-open container techniques have a drawback in that seal strength deteriorates significantly, especially in retort sterilization of oil-based foods (which makes them impractical for practical use).

In addition, in the technology of cutting the seal layer of an easy-to-open container with a peel-off structure and then peeling off the laminated strength with the adjacent layer, it is necessary to make the seal layer sufficiently thin. However, since the method of pressing the lid material with a fairly sharp force is adopted, it has the disadvantage that the lid material is damaged and the contents are affected by pinholes in the sealing part.

(Problems to be Solved by the Invention) The present invention overcomes the drawbacks of the conventional easy-open containers as described above and provides an easy-open container with excellent stability. To provide an easy-to-open container package that can be opened satisfactorily even by the elderly and children, while having a sealing strength that can withstand retort sterilization at 120° C. or higher.

8. Structure of the invention (means for solving problems) The means of the present invention for achieving the above-mentioned object is as follows: A flange portion is provided on the outer periphery of the opening for sealing by heat-sealing with the lid material. In the container, the upper surface of the flange or the surface corresponding to the flange of the lid material has a film interlayer strength of 2.5 kg.
/ Lid material for containers and packaging, which has an innermost plastic film having a thickness of 15 mm or more, and a sealant made of a plastic that has a cohesive failure property of 0.5 to 2.0 kg / 15 mm and an interlayer strength of the film adjacent to the film. By heat sealing from the side with a heat seal ring having a concavo-convex annular shape continuous on the outer and inner peripheries, it is possible to make the outer and inner annular parts of the flange-corresponding part of the sealant layer continuously thick and thin. It is based on an invention that is a powerful means of achieving a goal.

To explain the interlayer strength of the film, the plastic used for each layer is formed into a film with a thickness of 50 μm using an extrusion casting machine, and each film and the stretched nylon film with a thickness of 15 μm are bonded using adhesives commonly used in the industry. A sample is prepared by laminating using a dry lamination method using a chemical agent.

After the sample was fused and sealed between the sealing surfaces using a hot plate sealer, the test width was 15 mm + tensile speed was 3QQm.
The peel resistance value between the film layers under the conditions of m/min and a peel angle of 90'' was defined as the film interlayer strength.

Next, the present invention will be explained with reference to the accompanying drawings.

Figures 1-A and 1-B are plan views of round and square container packages hermetically sealed with lids; The outer periphery 5-1 and the inner periphery 5-3 shown in FIG.
, b, c.

d is an opening edge located outside the container flange that is required when opening the lid material.

Figures 2-1 and 2-2 are cross-sectional views of the container 1, with Figure 2-1 showing the sealant provided on the container 1 side, and Figure 2-2 showing the sealant on the lid 2 side. It was established.

Enlarged views of the heat-sealed portion where the container 1 and the lid member 2 are fused are shown in FIGS. 3-1 and 3-2, respectively.

Figures 4-1 and 4-2 show respective unsealed views.

By pulling down the lid material 2 in the six directions indicated by arrows in this figure, first, a cut 7 occurs in the thin part of the thick and thin layer of the sealant layer formed by the uneven seal on the outer periphery, and then the easily cohesive failure layer is cut. While cohesive failure 8 is occurring, the sealant layer is again cut 9 at the inner circumferential uneven seal portion to open the seal.

Note that another barrier film, such as a vinylidene chloride film, an ethylene-vinyl alcohol copolymer film, or a metal foil such as aluminum foil, may be composited between each base material layer and the sealant layer.

Interlaminar strength of the innermost layer (sealant layer): 2.5k
In the case of polypropylene, isotactic polypropylene can be used as the plastic having a g/15 mm or more, and the suitable thickness of this layer is 10 to 50 LLm, preferably 15 to 30 μm.

The interlaminar strength of the film adjoining the layer by fusion bonding is 0.
Plastics with easy cohesive failure of 5 to 2.0 kg/15 mm can be obtained by mixing isotactic polypropylene with polyethylene or an inorganic filler such as talc when the innermost layer is isotactic polypropylene. You are not limited to these methods.

The thickness of the layer is 10 μm or more, preferably 15 to 30 μm thick.
It is μm thick.

These plastics can be other polyolefins, polystyrene, polyesters, or mixtures thereof.

(Function) The present invention configured as described above exhibits the following effects.

The shape of the heat seal bar having unevenness on the outer circumference and inner circumference is shown in Fig. 5-IA, Fig. 5-2A, Fig. 5-3A, Fig. 1, Fig. 5.
As shown in the plan view of Fig.-4A and the front views of Fig. 5-13, Fig. 5-2B, Fig. 5-3B, and Fig. 5-4B, it is preferable to provide an uneven seal portion in the annular direction.

As shown in Fig. 5-2A, the purpose of the present invention can be achieved even if the concave and convex sealing is performed in the width direction of the annular shape, but the sealant layer is easily cut from the continuous thin part of the sealant layer in the width direction. It has the disadvantage that the chain of peeling action to the cohesive failure film layer tends to become unstable.

That is, in the structure of the present invention, it can be said that because the sealant layer has a continuous thickness and thinness in the peeling direction, a chain of peeling action to the easily cohesive failure film layer occurs stably.

In order to make the intermittent thin-walled parts of the innermost layer of the sealant easier to chain and cut, it is effective to make the intervals between the irregularities narrower, so it is said that an interval of about 0.5 to 2 mm is appropriate. I can do it.

From this point of view, it is preferable to provide the width of the unevenness, and the width of the unevenness is 1/4 of the width of the flange, with the outer circumference and inner circumference equally divided.
About 1/2 is preferable.

As shown in Figures 6-IA to 6-IC, the shape of the convex portion is rounded at the tip to prevent damage to the lid material, and the height is 0.5 The thickness is preferably about 1 mm.

FIG. 7 shows an enlarged view of the flange portion hermetically sealed by the manufacturing method of the present invention.

Furthermore, FIG. 8 shows an enlarged view of the part that was heated and pressed by the convex part of the sealer 5. Both ends of the sealer 5 were pressed up as shown in the figure, and a thin part 11 was created, and this part was reduced to 10 parts. When the unsealing force is applied, the peeling is chained to 12 parts of the easily cohesively broken film layer.

As mentioned earlier, the diagrams that have been opened are Figures 4-1 and 4.
- Shown in Figure 2.

Although the thickness structure of the sealant was determined as appropriate depending on the sealant structure determined by the contents, retort conditions, etc., it can be said that the thickness of the thin part is a substantially constant condition.

The thickness of the thin part is, for example, lO in the case of polypropylene.
The layer thickness is LLm or less, or 3 to 7 μm thick.

(Example) An example of an easy-to-open container package and a method for manufacturing the same according to the present invention will be described below with reference to the drawings.

In Fig. 2-1, the innermost layer 4-3 of the container which does not have easy cohesive failure (MFR value 9g/10m1n melting point 1
60℃, tensile strength 450kg/cm2. Elongation 400%
(MFR value 20g /
10m1n, melting point 150℃, tensile strength 300kg/
am”, isotactic polypropylene with 100% elongation and ethylene-propylene rubber with specific gravity of 0.88 (
EPR) with an MI value of 7. Specific gravity 0.92. Tensile strength 300kg/cm, elongation 500
10% polyethylene and 10% inorganic filler talc
(Using a blend resin mixed with wt%) and base material layer 4-1
f MFR value 2 g/10 m1n, melting point 165°C,
Using isotactic polypropylene with a tensile strength of 550 kg/cm" and an elongation of 500%), a multilayer sheet with a layer thickness of 800 μm (innermost layer film thickness 2
0 μm, intermediate layer thickness 30 μm, base sheet thickness 750 μm]
This sheet is then vacuum formed into a 50mm diameter sheet.

Depth 301. A multilayer container with a flange width of 10 mm was molded. After filling the container with pouch, a stretched nylon film with a thickness of 15 μm was added as a lid material, a polypropylene film with a thickness of 60 μm, which is commonly used in block copolymer retort pouch packaging materials in the industry, and a polyurethane adhesive were added. The lid material created by pasting is attached to the outer and inner periphery of the heat seal bar of the cup sealer, each having a width of 3 mm, 0, 5n+mφ, and a height of 1.
Heat sealing was performed over the entire width of the flange to seal the flange using a heat seal bar having hemispherical convex portions formed at 1 mm intervals.

When this product was retorted at 125°C for 30 minutes, cooled, and then opened, the peeling action was carried out smoothly starting from the thin wall on the outer periphery, and the thin wall on the inner rim was cut. By doing so, I was able to open the package.

No fluff or hangnails were observed on the peeled surface.

This heat-sealed portion was cut to a width of 15 mm and the seal strength was measured, and the seal strength was 1.8 kg/15 mm, indicating that it had sufficient protection strength.

(Comparative example) (a) The intermediate layer 4-2 of the multilayer container of the example was subjected to the same test as in the example, except that the inorganic filler talc was removed (and the inorganic filler talc was strengthened) to a film interlayer strength of 3.0 kg/15 mm. However, since the intermediate layer did not exhibit easy cohesive failure, the peeling action could not be smoothly chained to the intermediate layer after the innermost layer 4-3 was cut, so a considerable amount of force was required to open the package. At the same time, the peeled surface also lost its commercial value due to fuzzing and the like.

tb+Blend that allows interfacial separation of the intermediate layer 4-2 and the innermost layer 4-3, that is, high-density polyethylene (specific gravity 095) 50
wt% ethylene-propylene rubber (specific gravity 0.88)
20wt% and isotactic polypropylene (
By using a 30wt% blend resin (specific gravity: 0.90), a test similar to that of the example was conducted, but since the intermediate layer and the innermost layer were not adhered in a fused state, it was different from the comparative example (a). Similarly, since the point at which breakage was supposed to occur did not occur, 11 always resulted in a dirty peeling surface and no commercial value.

C. Effects of the Invention The easy-to-open container packaging of the present invention can reduce the initial opening strength by forming a thick and thin sealant having continuous unevenness, making it extremely easy to open. The sexual packaging had the disadvantage that it could not be opened by the elderly, children, or girls, but this problem has been solved in the configuration of the present invention.

Since the seal protection strength is obtained by the interlayer strength of the intermediate film layer at the center of the flange other than the seal shape, the structure has very stable strength and is particularly excellent in retort resistance, oil resistance, etc.

The lid sealant and the container sealant have excellent contamination sealing properties because they are fused and sealed using similar plastics.

Compared to easy-to-open containers and packaging with interfacial peeling or glabella peeling structures, the range of sealing conditions is wider and the sealing strength is more stable.

Since it can also be used as an easy-to-open container for foods that have been sterilized at room temperature or by boiling, it can be said that the scope of use of this container packaging is extremely wide.

[Brief explanation of the drawing]

1-A and 1-8 are plan views of containers related to the present invention. 2-1 and 2-2 are longitudinal sectional front views showing the molded state of the package. FIG. 3-1 is a sectional view showing a fused state of a seal portion when a sealant is provided on a container flange. 3rd-
FIG. 2 is a sectional view showing a fused state of a seal portion when a sealant is provided on the lid material. FIG. 4-1 is an enlarged front view showing the peeled state in FIG. 3-1. FIG. 4-2 is an enlarged sectional view showing the peeled state in FIG. 3-2. 5-IA ~ 5-4A
The figure is a partial plan view showing the uneven pattern. 5th-IB~
Figure 5-4B is a side view of the heat seal bar forming the uneven pattern. 6-IA to 6-IC are enlarged views showing the convex portion same as above. FIG. 7 is a cross-sectional view showing the molded state of the concavo-convex pattern. FIG. 8 is an enlarged sectional view of the same as above. In the figure, 1 is a container, 2 is a lid material, 3-2 is an annular part on the inner and outer periphery of the flange, 4-2 is a plastic layer that does not have easy cohesive failure, and 4-3 is a plastic layer that has easy cohesive failure. be. No.-A/-8 Figure 1 Figure 6-IA Figure No.-IB No.-IA Procedural amendment (□, Director General of the Japan Patent Office Yoshi 1) Moon Yi 1, Indication of the case 1999 Patent Application No. 121190 2. Name of the invention: Easy-to-open container/package and its manufacturing method 3. Relationship with the case of the person making the amendment Patent applicant Sunny Chemical Industry Co., Ltd. 4. Agent (1) The “scope of claims” in the specification Correct as shown in the attached sheet. (2) Same as above, page 6, line 11, page 9, line 11, “0.5 to 2
．． 0kg/15mmJ means rO, 3~2.0 kg
/15mmJ. 5. Date of amendment order Month, Day, 2016 6. "Claims" in the specification subject to amendment, "Claims of the invention + 1) Innermost plastic film with film interlayer strength of 2.5 kg/15 mm or more The interlayer strength of the fused film adjacent to the film [1.3-20kg/
In a container equipped with a lid material and a flange for sealing by heat sealing around the outer periphery of an opening manufactured from a multilayer plastic sheet using a 15 mm cohesively ruptureable plastic as a sealant, the outer and inner annular parts of the flange are An easy-to-open container package, characterized in that the lid is sealed by heat sealing into a continuous uneven shape. (2) A sealant is applied to the outer and inner annular parts corresponding to the container flange of the lid material in which the sealant is composited with the lid base material, and the lid is applied by heat sealing in a continuous uneven shape. The easily openable container package according to claim m. (3) The easy-open container package according to claim 11 or (2), wherein the method for heat-sealing the uneven shape is heat-sealing using a seal ring having a continuous uneven shape. Production method.

Claims (3)

[Claims] (1) A film that is fused and bonded adjacent to the innermost plastic film having an interlayer strength of 2.5 kg/15 mm or more has an interlayer strength of 0.5 to 2. In a container equipped with a lid material and a flange for sealing by heat sealing on the outer periphery of an opening manufactured from a multilayer plastic sheet using a plastic having a cohesive failure property of 0 kg/15 mm as a sealant, the outer and inner annular shapes of the flange 1. An easily openable container package, characterized in that the lid is sealed by heat sealing in a continuous uneven shape. (2) A sealant is applied to the outer and inner annular parts corresponding to the container flange of the lid material in which the sealant is composited with the lid base material, and the lid is applied by heat sealing in a continuous uneven shape. The easily openable container package according to claim (1). (3) The easy-open container package according to claim (1) or (2), wherein the method for heat-sealing the uneven shape includes heat-sealing using a seal ring having a continuous uneven shape. manufacturing method.