JPS5924700Y2 - Cup-shaped easy-open container - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a novel cup-shaped easy-to-open container.

In recent years, pasty foods such as jam, marmalade, and peanut butter are often sold in paper-based cup-shaped containers, and instant ramen noodles, instant shiruko, and other foods are also sold in similar containers. It is widely used as cup ramen, cup soup powder, etc.

This cup-shaped container is made by applying wax to both sides of a conventional cup-shaped paper container for protection and reinforcement, or by applying polyethylene to the inside and wax to the outside, or by applying polyethylene to both sides. It was getting worse.

On the other hand, the lid for this container is usually made of aluminum foil, and the inside is coated with various sealants such as heat seal coating agent, hot melt adhesive, polyethylene/hot melt adhesive, polyethylene, etc. It had been.

In this way, a lid made of the above-mentioned material was placed on the edge of the container made of the above-mentioned material, and the lid was adhered to the edge of the container using the various sealants mentioned above.

However, many of the materials used here had some drawbacks in terms of hygiene.

The heat seal coating agent and hot melt adhesive used in the lid are low molecular weight ones, such as ethylene-vinyl acetate copolymer or vinyl chloride-vinyl acetate copolymer. Waxes and tackifiers were used, but these low polymers may adhere and precipitate if they come into direct contact with the contents.
This causes deterioration of the contents and poses a hygiene problem.

On the other hand, polyethylene does not adhere or precipitate when it comes into contact with food, and does not cause deterioration of the contents. However, when polyethylene is used for heat sealing, it does not peel well when peeled, resulting in the paper layer cracking and the container being damaged. This has been problematic as a lid sealant since it may cause damage.

Thus, the present invention can be used with a lid using polyethylene as a sealant, and can be easily opened in the form of a paper cup without causing deterioration of the contents, and without causing the paper layers to crack or the container to be damaged. According to the present inventors, the purpose is to provide an openable container, which consists of a paper cup-shaped container having a body and a bottom with a rim, and at least the rim The cup-shaped part is formed by laminating a paper cup material, a support film, and a release film, the support film is made of polyethylene, and the release film is made of a polyolefin three-component blend polymer having a molecular weight of 10,000 or more. It was discovered that easy-to-open containers could be used to achieve this goal.

To explain in more detail one embodiment of the present invention shown in the drawings, in FIG. A state where it is sealed by the heater par 6 is shown.

Here, for convenience during manufacturing, the body part 2 and the edge part 1, including the folded part 7, are integrally made of the same material.

That is, it is formed of four layers: a release film 8, a polyethylene film 9 serving as a support film, a cup base paper 10, and a polyethylene or wax 11 in order from the inside that contacts the contents and the lid.

As the support film, a film made of medium density polyethylene or a blend polymer of high density polyethylene and low density polyethylene is used.

As the release film, a three-component polyolefin blend polymer having a molecular weight of 10,000 or more, consisting of ethylene, polypropylene, and ethylene-propylene copolymer, is used, and is formed to a thickness of 5 to 15 microns.

The layer of polyethylene 9 is usually formed to a thickness of 20 to 50 microns, and the thickness of the cup base paper 10 is usually 200 to 500 microns.
A material with a basis weight of K(1)· is used.

Similarly, from the inside, the bottom part 3 is made of polyethylene 12 with a thickness of 20 to 50 microns, and a cup base paper 1 with the same basis weight as before.
3. Consisting of a layer of polyethylene or wax 14.

The body 2 and bottom 3 are heat sealed at 15.16, respectively.

The lid 5 that seals this container is made by laminating aluminum foil 17 with a thickness of 30 to 60 microns and polyethylene 18 with a thickness of 20 to 50 microns, with the polyethylene 18 at the bottom and around the edge of the container. and come into contact with the contents.

When the joint edge 1 is pressurized by a heated heater par 6, the polyethylene 18 of the lid 5 and the separation film 8 of the container 4 are brought into close contact and heat-sealed.

When peeling off the sealed lid 5 at the time of opening, remove the release film 8 from the heat-sealed part as shown in FIG.
’ is cut and separated, and the polyethylene 1 of the lid seal part is removed.
It is opened by moving it to the lid 5 side while remaining fixed to the lid 8.

If the release strength of the release film is stronger than the interlayer strength of the cup base paper, the paper will naturally crack when opened, making it difficult to open easily and resulting in poor appearance. If the adhesion strength of the container is too weak, the sealing strength will naturally become weak and there will be concerns about the protection of the contents.

However, when a polyolefin-based three-component blend polymer is used as the release film as in the present invention, a good balance is created between the release strength of the release film and the interlaminar strength of the cup base paper, and there is no layer cracking and the contents can be easily absorbed. Good ease of opening can be achieved without affecting the protection of the product.

Therefore, polymers with low molecular weight or low degree of polymerization may melt, precipitate, or adhere at high temperatures or even at room temperature, but in this invention, both the lid and the container are made of polymers with such low molecular weight and low degree of polymerization. Since a polyolefin polymer with a molecular weight of 10,000 or more is used, there is no risk of such precipitation or adhesion, and it is safe to use in areas that come into contact with contents.

Also, the polyethylene or wax 11 provided on the outside of the cup base paper 10 protects and reinforces the base paper 10, and in particular serves as waterproofing, while the polyethylene 8 provided on the inside serves as a kind of adhesive for the paper. It also adheres well to the base paper,
Therefore, it works to prevent delamination of the base paper when the package is opened.

Therefore, the polyethylene on both sides of the cup base paper serves as a support film for the cup base paper.

From the viewpoint of ease of opening, the four-layer structure only needs to be formed at the edges, but for convenience during manufacturing, the body and the body are usually formed into four layers.

As shown in the drawings, the bottom part is formed in three layers separately from the body part.

The polyethylene 12, 14 on both sides of the bottom serves as a supporting film for the cup base paper 13, as in the case of the body.

Therefore, in the present invention, a three-component blend polymer of low-density polyethylene, an ethylene-propylene copolymer, and polypropylene is used as the release film. It has good compatibility and provides appropriate weldability when performing two-layer extrusion lamination as described below.

An example of the manufacturing method of the container of the present invention will be explained below with reference to the drawings.

Base paper basis weight 300 g/m2, thickness 320 microns, density 0.94, size degree 1000 seconds, outer surface 30 micron polyethylene coating interlayer strength 100 g 715 mm width (200 mm 7 minute shopper) Figure 3 is printed on the inner surface of the cup base paper with the above specifications. Coextrusion lamination 1 was carried out using a coextrusion lamination apparatus such as the following.

First, medium density polyethylene (melt index MI=12, density dO, 94
2) or a blend polymer of high density polyethylene and low density polyethylene MI=7.5, d=0.963 and MI=
8, 50:50 (weight ratio) blend polymer with d=0.98) is melt extruded, and low density polyethylene (MI=6.5, d= 0.917), ethylene-propylene copolymer (MI=4.0. d=0.8
8), polypropylene (MI=18.0, d=0.90
(230°C)) respectively by weight: 40:30:
A two-layer laminate 22 is obtained by laminating polyolefin-based three-component blend polymers blended at a ratio of 30% by using a two-layer die 21 in a melt-extrusion die.

The temperature during extrusion is 320-330°C, and the thickness of the laminate is 40 microns (support film - 30 microns, release film - 10 microns).

On the other hand, corona treatment 24 is applied to the base paper surface of a laminate 23 made of base paper whose outer surface is coated with polyethylene to a thickness of 30 microns as per the above specifications, and then a press roll 25 is used to coat the base paper surface with the polyethylene of the two-layer laminate. are brought into contact and pressed together to perform coextrusion lamination, which is then cooled by a cooling roll 26 and wound up by a rewinder 27 to obtain the material for the edges and body of the four-layered shell.

The bottom is made of base paper as described above with low density polyethylene on both sides.
It is made by extrusion laminating and laminating to a thickness of 0 microns, and the lid is made by applying a urethane anchor coating agent to a 40 micron thick aluminum foil, drying, and then applying low density polyethylene to a thickness of 30 microns. Made by laminating with extrusion laminate.

To manufacture a container using each of the above members, the body and bottom materials are designed and cut to have a content of 100 ml, and the body and bottom are sealed using an appropriate heat sealing device as shown in Figure 1 to obtain the container. Ta.

(The width of the body seal is 10 mm, the width of the bottom seal is 5 mm,
These shear pee 1 ~ seal strength is 1.5 kg715
A width of more than mm was obtained.

) The lid was heat-sealed on the edge of the lidded container produced as described above at a temperature of 200° C., a pressure of 3 kg/cm□, and a time of 1 second.

When the rear lid was peeled off and opened, it was possible to peel and open the bag in an ideal peeling state as shown in FIG.

At this time, 90 peel strength (ASTM-D-882-64
Tensile test of Schottspa set based on T, 200 mm with @ machine
/min) was approximately 0.5 kg/15 mm, which was an ideal value for easy-opening strength.

The polyethylene layer of the heat seal part was not peeled off and remained in close contact with the base paper even after opening, and the base paper was safe without any delamination.

The above-mentioned example is just one preferred example and should not be limited to this, and it goes without saying that various modifications may be made within the scope of the present invention.

In this way, the container of the present invention can be easily opened without causing any layer cracking of the cup material such as base paper and without damaging the appearance, and is also safe as it does not cause any deterioration of the contents. An easy-to-open container can be obtained, and the present invention can provide a truly effective container for this product.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing an example of the container according to the present invention in a closed and sealed state, Fig. 2 is an explanatory view showing the edge of the container when opened, and Fig. 3 is an example of the manufacturing method of the container. FIG. 4... Container, 5... Lid, 6...
... Heater par 8 ... Release film, 10
．． 13...Cup base paper, 17...Aluminum foil, 19.20...Extruder, 21...
····dice.

Claims (1)

[Scope of utility model registration request] In a paper cup-shaped container having a body and a bottom with an edge, at least the edge is formed by laminating a paper cup material, a support film, and a separation film, and the support film is made of medium-density polyethylene or high-density polyethylene. A paper cup made of a blend polymer of density polyethylene and low density polyethylene, wherein the release film is made of a polyolefin-based three-component blend polymer of low density polyethylene, ethylene-propylene copolymer, and polypropylene with a molecular weight of 10,000 or more. Easy-open container.