JPH10101143A - Easily opening cover material and container used thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To increase the easily opening property of a cover material and also increase the barrier capacity and the pressure-resistant capacity and further, increase the adaptability for food, by a simple processing and low-cost means. SOLUTION: After a heat-adhesive resin layer 13 made of unstretched polypropylene film has been laminated in a dry condition on the rear face of a base material layer 12 made of a polyester film provided with a pattern- printed layer 11 at one side face, for instane, a release agent layer 14 wider than the seal part 3 is formed at a specified position of the front side of the base material layer 12 to correspond with the seal part 3, and a pattern-printed layer is formed on the release agent layer 14, and cutting lines 15, 16 of perforations piercing the base material layer 12 from the heat-adhesive resin layer 13 and stretching so as to form a ring, are formed in accordance with the external peripheral position and the internal peripheral position of the release agent layer 14, and further, a barrier layer 17 (transparent resin layer) is formed on the pattern-printing layer 11.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technology for easily opening containers used for packaging retort foods and the like.

[0002]

2. Description of the Related Art For a container such as a container for retort food which is required to have both the sealing property before opening and the easy opening property at the time of opening, the container body has a flange at the periphery of the top opening. As a lid material, a laminated film having a heat-adhesive resin layer provided on the back surface of the base material layer is used, and the heat-adhesive resin layer is applied to the flange portion of the container body and melt-sealed. A release agent layer wider than the seal part is provided on the part corresponding to the seal part on the back surface of the base material layer, and when the lid is pulled up with the knob on the peripheral part of the lid material, the seal part of the heat-adhesive resin layer is Conventionally, the lid material is peeled off from the layer, leaving that portion.

[0003] As an easy open method,
In addition, the container body and the flange portion of the opening peripheral edge thereof are formed by a laminated sheet composed of a base material layer and a release layer so that the release layer is on the surface side of the flange portion, and inside the seal portion of the flange portion. By providing a notch over the entire circumference of the portion of the release layer located, or by reducing the thickness of the release layer of the same portion over the entire circumference, the release layer is lifted together with the lid material at the peripheral portion at the time of opening, and the notch or the thickness is reduced. In some cases, the release layer is cut at the portion where the cover material is peeled off. Japanese Utility Model Publication No. 6-47773 discloses a container which is provided with an easy-open property by such a method. In addition, actual fairness 6-9626
Publication 3 discloses a method for manufacturing such a container.

Japanese Patent Application Laid-Open Nos. 62-208375 and 2-219769 disclose that a substrate having an inner surface having heat sealability and an outer surface peeling layer are provided with an adhesive layer and a resin layer having a weak adhesive force. Laminating through, and providing a discontinuous cut in the base material to surround the opening, by removing the resin layer with a weak adhesive force in the part inside the cut, causing the outer surface peeling layer, upward When pulled, the outer release layer is peeled off from the base material, and only the opening part is lifted with the outer release layer, the substrate is broken along the cut, and the opening is formed. Have been.

Japanese Utility Model Application Laid-Open No. 55-139073 discloses that in a cover material provided with a heat seal layer on one side of a base material containing a metal foil such as aluminum, the metal foil is completely cut from the surface side of the base material. This publication describes that a cut is formed, and the cut forms a continuous opening portion to the tab.

[0006]

In the case where a release agent layer is provided in a portion corresponding to a seal portion on the back surface of a base material layer of a lid material,
When pulling up with the knob on the peripheral edge of the lid material, the seal part of the heat-adhesive resin layer peels off at the interface, but the heat-adhesive resin layer tears diagonally inside that part and the peeled surface becomes dirty, Inconveniences such as delamination, a part of which remains, and the inability to open the package are likely to occur.

In the case where a release layer is provided on the container body side and a cutout or thin portion is provided in the release layer, the container body needs to have a laminated structure of a base material layer and a release layer. It is necessary to form a notch or a thin portion in a ring shape in the release layer of the flange portion later, and such a notch or a thin portion is formed by forming a laminated sheet into a container shape, and further punching into an individual container. However, it must be formed in a separate process by pressing with a hot plate, and the process is complicated and troublesome, resulting in high cost. It is not impossible to form cutouts and thin-walled parts in a multi-layered state before individually punching the molded containers.However, the degree of expansion and contraction between the center and the edge of the sheet by pressing with a hot plate is not impossible. And the registration becomes difficult.

[0008] Further, the base material and the outer surface peeling layer are laminated via an adhesive layer and a resin layer having low adhesive strength, and a discontinuous cut is provided in the base material so as to surround the opening portion. Is to remove the resin layer with low adhesive strength,
It is necessary to distribute a weakly adhesive resin layer at the interface of the adhesive layer, which complicates the process. In addition, since the weakly adhesive resin layer exists on the outer peripheral portion of the lid material, the outer surface peeling layer is inadvertent. And the sealability may be impaired.

[0009] Further, a device in which a notch for completely cutting the metal foil from the surface side of the base material including the metal foil has a problem in barrier properties, and can be used for a material subject to an internal pressure. Use is limited.

[0010] Therefore, it is an object to improve the easy-opening property of the lid material by means of simple processing and low cost.

Another object is to maintain the barrier properties so that it can be used for applications requiring an internal pressure.

Another object of the present invention is to prevent the ink surface of the pattern printing layer from being exposed to the flange of the container when the container is opened, especially for food.

[0013]

According to the present invention, there is provided a thermo-adhesive resin layer on the back surface of a base material layer, the thermo-adhesive resin layer abutting against a flange portion of a container body and being melt-sealed at a predetermined seal portion. The present invention relates to a lid material and a container using the lid material, wherein the lid material penetrates the base material layer from the heat-adhesive resin layer and extends in a ring shape corresponding to the outer periphery and the inner periphery of the seal portion. With a shape-like cut, on the surface side of the base material layer, having a release agent layer from a position corresponding to the cut on the outer peripheral side to a position corresponding to the cut on the inner peripheral side, and a transparent resin layer on the outermost surface It is characterized by having.

The perforated cut is made by laminating the base material layer and the heat-adhesive resin layer by dry lamination or the like, providing a release agent layer by gravure printing or the like, and then mechanically starting from the heat-adhesive resin layer side. It can be formed and does not require complicated steps.

The lid is placed over the opening of the container body and is melt-sealed at the flange. Then, at the time of opening, when the lid material is lifted up by holding a predetermined portion of the peripheral edge of the lid material, the lid material is integrally lifted outside the seal portion, and the seal strength of the seal portion is determined between the cut on the outer peripheral side and the cut on the inner peripheral side. Since the laminating strength of the release agent layer is also weaker, the transparent resin layer side is peeled off leaving the substrate layer side at the boundary of the release agent layer, and the substrate layer side again becomes the transparent resin layer side inside the inner peripheral side cut. Open together. In this case, the base material layer and the heat-adhesive resin layer are reliably and easily separated at the cut portions on both sides of the seal portion. Therefore, the lid material is peeled off cleanly without leaving the portion sandwiched between both cuts without causing the peeled surface to become dirty or causing delamination. Further, by making the transparent resin layer have a barrier property, the sealing property before opening can be secured, and the internal pressure resistance can also be secured.

[0016] Of the cuts on the outer circumferential side and the inner circumferential side of the cover material, particularly the cuts on the inner circumferential side are preferably closed on the rearmost surface side of the cover material so that the contents do not enter. For this purpose, for example, after the transparent resin layer on the outermost surface is dry-laminated, the cut portion on the inner peripheral side is pressed with a seal bar from the back surface side. Alternatively, when the transparent resin layer is dry-laminated, a film of the heat-adhesive resin is co-extruded to close the cut.

The pattern printing layer is provided, for example, between the release agent layer and the transparent resin layer. In this case, when the transparent resin layer side peels off between the cut on the outer peripheral side and the cut on the inner peripheral side, the picture printing layer is peeled off together with the transparent resin layer, and the ink of the picture printing layer does not remain on the flange portion of the container.

The pattern printing layer may be provided between the base material layer and the release agent layer. In this case, by setting the adhesion strength between the release agent layer and the pattern printing layer side to be larger than the adhesion strength between the release agent layer and the transparent resin layer side, the transparentness between the cut on the outer peripheral side and the cut on the inner peripheral side is increased. When the resin layer is peeled off, a release agent layer remains on the substrate layer side so as to cover the pattern printing layer. Therefore, the ink of the picture printing layer is not exposed on the flange of the container.

The picture printing layer may be provided between the base material layer and the heat-adhesive resin layer. In this case, even if the transparent resin layer side is peeled off between the cut on the outer peripheral side and the cut on the inner peripheral side, the ink of the pattern print layer is exposed on the container flange because the pattern print layer is covered by the base material layer. There is no.

Further, it is desirable that the lid member is partially adhered to the flange portion of the container body outside the notch on the outer peripheral side. By doing so, it is possible to prevent the lid material from being inadvertently peeled off by an external force applied to the knob during transportation and at the store.

[0021]

1 to 4 show an example of an embodiment of the present invention. In the figure, 1 is a container body in the shape of a circular cup, and 2 is a lid material in a sheet shape. The container body 1
It is a molded product of PP (polypropylene) and has a flange portion 1a on the periphery of the top opening. After filling the contents, the lid member 2 is put on the top of the container body 1, and the peripheral portion is melt-sealed to the flange portion 1 a of the container body 1.
Has a shape and size corresponding to the outer shape of the flange portion 1a, and has a knob 2a for opening at one peripheral edge portion. In FIG. 1, a portion with vertical hatching is a seal portion 3.

The lid member 2 is made of, for example, a PET having a thickness of 12 μm.
After providing a heat-adhesive resin layer 13 made of a CPP (unstretched polypropylene) film having a thickness of 50 μm by dry lamination on the back surface of the base material layer 12 made of a (polyester) film, the base material layer corresponding to the seal portion 3 is provided. 12, a release agent layer 14 wider than the seal portion 3 is provided at a predetermined position on the front side, and a pattern printing layer 11 is provided on the release agent layer 14 by gravure printing. Perforated cuts 15 and 16 extending in a ring shape through the base material layer 12 from the side of the heat-adhesive resin layer 13 are formed corresponding to the position and the inner circumferential position. Thickness 1 with silica evaporated on one side on picture printing layer 11
The barrier layer 17 made of a 2 μm PET film is joined by dry lamination. In the figure, 1
8 and 19 are adhesive layers.

The lid material 2 has the heat-adhesive resin layer 13 side against the flange portion 1 a of the container body 1 and is melt-sealed by a seal bar 7. As a result, the sealing portion 3 is formed. The portions with double hatching indicated by 3a in FIGS. 3 and 4 are complete seal portions.

In the drawing, reference numeral 20 denotes a point seal portion set at the base of the knob 2a outside the cut 15 on the outer peripheral side. In this point seal portion 20, the lid member 2 is partially adhered to the flange portion 1a of the container body 1, thereby preventing inadvertent peeling of the lid member 2 during transportation and at the store.

This container can be neatly opened as shown in FIG. 4 by pulling up on the tab portion 2a of the lid member 2. That is, when the knob 2a is pulled up, the sealing strength (about 1500 to 3000 g / 15 mm) is obtained.
Laminate strength of release agent layer 14 (300 g / 15 m) rather than width
m width to 1300 g / 15 mm width), the base layer 12 and the heat-adhesive resin layer 13 are peeled off between the outer cut 15 and the inner cut 16 on the flange 1a side. It peels off at the interface between the agent layer 14 and the base material layer 12. Then, inside the notch 16 on the inner peripheral side, the lid member 2 is opened again integrally. At that time, the base material layer 1
2 and the heat-adhesive resin layer 13 are surely and easily separated at the cuts 15 and 16 on both sides of the sealing portion 3, and the lid 2 is peeled off cleanly except for the portion sandwiched between the cuts 15 and 16. Further, the barrier layer 17 ensures the barrier property before opening. When the knob 2a is pulled up, the point seal portion 20 is easily peeled off since the joining area is small.

FIGS. 5 and 6 show another embodiment of the present invention. In this example, the lid material 2 is, for example, a heat-adhesive resin layer made of a 50 μm thick CPP (unstretched polypropylene) film by dry lamination on the back surface of the base material layer 12 made of a 12 μm thick PET (polyester) film. After providing the pattern 13, the pattern printing layer 11 is provided on the front side of the base material layer 12, and a release agent layer 14 wider than the sealing portion 3 is provided at a predetermined position corresponding to the sealing portion 3 from above the pattern printing layer 11. Perforated cuts 15 extending in a ring shape through the base material layer 12 from the side of the heat-adhesive resin layer 13 corresponding to the outer peripheral position and the inner peripheral position of the release agent layer 14, And a thickness 12 of silica-deposited on one side of the pattern printing layer 11 and the release agent layer 14 on the front side of the base layer 12.
A barrier layer 17 made of a PET film having a thickness of μ was joined by dry lamination. In the figure, 18
And 19 are adhesive layers.

In the case of this embodiment, the lid 2 is also provided with the heat-adhesive resin layer 13 on the flange portion 1a of the container body 1 and melt-sealed by the seal bar 7. As a result, the sealing portion 3 is formed. The portions with double hatching indicated by 3a in FIGS. 5 and 6 are complete seal portions.

Also in this example, the container is a knob 2 of the lid 2.
By pulling up with a, it is possible to cleanly open the package as shown in FIG. That is, when the knob 2a is pulled up, the sealing strength (about 1500 to 3000 g / 1) is obtained.
5 mm width) rather than the lamination strength of the release agent layer 14 (300 g /
15 mm width to 1300 g / 15 mm width) is weaker, and since the adhesion strength between the release agent layer 14 and the pattern printing layer 11 is larger than the adhesion strength between the release agent layer 14 and the adhesive layer 19, Between the cut 15 and the cut 16 on the inner peripheral side, the picture print layer 11, the base material layer 12, and the heat-adhesive resin layer 1
The adhesive layer 19 is formed in such a manner that the adhesive layer 3 is left integrally on the flange 1a side.
And the barrier layer 17 are separated at the interface with the release agent layer 14,
Inside the notch 16 on the inner peripheral side, the entire lid member 2 is opened again integrally as one body. At this time, the base material layer 12 and the heat-adhesive resin layer 13 are also separated easily and reliably at the cuts 15 and 16 on both sides of the sealing portion 3, and the lid is left except for the portion sandwiched between the cuts 15 and 16. Material 2 peels cleanly. Further, the barrier layer 17 ensures the barrier property before opening.

FIGS. 7 and 8 show still another embodiment of the present invention. In this example, the cover material 2 corresponds to the pattern printing layer 11 on the back surface of the base layer 12 made of, for example, a 12 μm thick PET (polyester) film, and the seal portion 3 on the surface of the base layer 12. A release agent layer 14 wider than the seal portion 3 is provided at a predetermined position by gravure printing, and a 50 μm thick CPP (unstretched polypropylene) film is dry-laminated on the back surface of the base material layer 12 with the pattern printing layer 11 interposed therebetween. A heat-adhesive resin layer 13 is formed from the heat-adhesive resin layer 13 side and the base layer 12
Perforated cut 15, extending through the ring and extending in a ring shape,
16 and the release agent layer 1 on the front side of the base material layer 12.
4 from above, 12μ thick PET with silica deposited on one side
The barrier layer 17 made of a film is joined by dry lamination. In the figure, 18 and 19
Is an adhesive layer.

In the case of this example, the lid 2 is also applied with the heat-adhesive resin layer 13 to the flange 1 a of the container body 1 and is melt-sealed by the seal bar 7. As a result, the sealing portion 3 is formed. The double-hatched portions indicated by 3a in FIGS. 7 and 8 are complete seal portions.

Also in this example, the container is a knob 2
By pulling it up with a, it is possible to cleanly open it as shown in FIG. That is, when the knob portion 2a is pulled up, the sealing strength (about 1500 to 3000) still remains.
g / 15 mm width) of the release agent layer 14 (30
0 g / 15 mm width to 1300 g / 15 mm width), and the adhesion strength between the release agent layer 14 and the base material layer 12 is smaller than the adhesion strength between the release agent layer 14 and the adhesive layer 19. Side cut 15 and inner circumferential side cut 16
At the interface between the release agent layer 14 and the base material layer 12, the release layer 14 is formed on the barrier layer 1 so that the base material layer 12, the pattern printing layer 11, and the heat-adhesive resin layer 13 are integrally left on the flange 1 a side.
7, and the entire lid 2 opens again integrally with the inner side from the cut 16 on the inner peripheral side. At this time, the base material layer 12 and the heat-adhesive resin layer 13 are also separated easily and reliably at the cuts 15 and 16 on both sides of the sealing portion 3, and the lid is left except for the portion sandwiched between the cuts 15 and 16. Material 2 peels cleanly. Also, the barrier layer 17
This ensures a barrier property before opening. It is also possible to set such that the release agent layer 14 is left on the base layer 12 side between the cuts 15 and 16.

In each of the above examples, the base material layer 12 has a thickness of 1
Other than a 2μ PET film, for example, a 16μ thick PET
A film or the like may be used. In addition, the heat-adhesive resin layer 13
Is suitable for a CPP film having a thickness of 50 to 100 μm. In addition to the above-mentioned 12 μm-thick silica-deposited polyester film, a 12 μm-thick alumina-deposited PET film, and a 15 μm-thick Et-Val
A single-layer film such as (ethylene-vinyl alcohol copolymer) can be used. For example, a two-layer film composed of ON (stretched nylon) having a thickness of 15 μ and Et-Val having a thickness of 15 μ can be used. Various transparent resin films can be used.

Further, both the outer peripheral side and the inner peripheral side cuts 1
5 and 16 are preferably set at positions separated from the outer circumference and the inner circumference of the seal portion 3 so as to absorb the registration error.
Is preferably about 2 mm. In addition, it is preferable that the notch 16 on the inner peripheral side is further separated from the outer peripheral side in order to facilitate registration and prevent separation due to internal pressure.

The inner perforated cut 16
May be penetrated depending on the contents. Then, after the barrier layer 17 is dry-laminated, the portion of the cut 16 on the inner peripheral side is pressed from the back side with a seal bar, or when the barrier layer 17 (or the transparent resin layer) is dry-laminated, the CPP having a thickness of 10 to 20 μm is used. The cut 16 is preferably closed by co-extruding the film.

The lids and containers of the above examples are suitable for retort foods and boiled foods, but can also be applied to various other uses.

[0036]

According to the present invention, the base material layer and the heat-adhesive resin layer of the lid member can be easily and neatly opened by linearly tearing the outer peripheral side and the inner peripheral side of the sealing portion of the container body. Yes, easy openness is improved. In addition, since there is no need to perform processing on the container body side, processing is simple, cost can be reduced, barrier properties can be maintained, and the present invention can be applied to applications requiring internal pressure. Further, especially for foods, it is possible to prevent the ink surface of the pattern printing layer from being exposed on the flange portion of the container when opened.

[Brief description of the drawings]

FIG. 1 is a sectional view of a container according to the present invention.

FIG. 2 is a rear view of a lid member according to the present invention.

FIG. 3 is a schematic cross-sectional view of a sealed portion of the container according to an embodiment of the present invention in a sealed state.

FIG. 4 is a schematic cross-sectional view of a sealed portion when the container shown in FIG. 3 is opened.

FIG. 5 is a schematic sectional view of a sealed portion of a container according to another embodiment of the present invention in a sealed state.

FIG. 6 is a schematic cross-sectional view of a sealed portion when the container shown in FIG. 5 is opened.

FIG. 7 is a schematic cross-sectional view of a sealed portion of a container according to still another embodiment of the present invention in a sealed state.

FIG. 8 is a schematic cross-sectional view of a sealed portion when the container shown in FIG. 7 is opened.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Container main body 2 Lid material 3 Seal part 12 Base material layer 13 Thermal adhesive resin layer 14 Release agent layer 15 Perforated cut (outer peripheral side) 16 Perforated cut (inner peripheral side) 17 Barrier layer (transparent resin) Layer) 20 point seal

Claims (8)

[Claims] 1. A lid material having a heat-adhesive resin layer on the back surface of a base material layer, wherein the heat-adhesive resin layer abuts a flange portion of a container body and is melt-sealed at a predetermined seal portion. A perforated cut extending through the base material layer from the heat-adhesive resin layer of the material and extending in a ring shape corresponding to the outer periphery and the inner periphery of the seal portion, and the surface of the base material layer Side has a release agent layer from a position corresponding to the cut on the outer peripheral side to a position corresponding to the cut on the inner peripheral side, and has an easy-open property characterized by having a transparent resin layer on the outermost surface. Lid material. 2. The easy-open lid material according to claim 1, wherein the cut on the inner peripheral side is closed on the lowermost surface of the lid material. 3. The easy-open lid material according to claim 1, wherein a pattern printing layer is provided between the release agent layer and the transparent resin layer. 4. A pattern printing layer is provided between the base material layer and the release agent layer, and the adhesive strength between the release agent layer and the pattern printing layer side is between the release agent layer and the transparent resin layer side. The easy-opening lid material according to claim 1 or 2, wherein the lid material is set to be larger than the adhesion strength. 5. The easy-open lid material according to claim 1, wherein a pattern printing layer is provided between the base material layer and the heat-adhesive resin layer. 6. The easy-open lid material according to claim 1, wherein said transparent resin layer has a barrier property. 7. A container body having a flange at the periphery of the top opening, and a heat-adhesive resin layer on the rearmost surface, wherein the heat-adhesive resin layer abuts the flange of the container body and is melt-sealed at a predetermined seal portion. And a perforated notch extending through the heat-adhesive resin layer and the base material layer of the lid material and extending in a ring shape corresponding to the outer periphery and the inner periphery of the seal portion. Having a release agent layer from a position corresponding to the cut on the outer peripheral side to a position corresponding to the cut on the inner peripheral side on the surface side of the base material layer, and having a transparent resin layer on the outermost surface A container using an easy-open lid material characterized by the above-mentioned. 8. The container according to claim 7, wherein the lid member and the flange portion of the container body are partially bonded outside the notch on the outer peripheral side.