JP2000043915A - Pressure-resistant lid body - Google Patents

Abstract

PROBLEM TO BE SOLVED: To lessen deformation of a lid body by increase or decrease of internal pressure of a container and to improve tightness in sealing and external appearance for the container by a method wherein the top plate of the lid body tightly sealing the container by means of heat welding and fitting is formed in a shape protruding downward with a step formed at a place near the circumferential wall. SOLUTION: For a lid body 100 made of thermoplastic resin for tightly sealing a container with a heat welding part 131 and a fitting part 121 that are applied to the container body, the top plate 110 of the lid body 100 is formed in a shape protruding downward with a step provided at a place near the circumferential wall 120 while a groove part having a groove at the upside of its periphery and protruding downward is formed. A reinforcement rib may be provided at the surface facing the inside of the container of the top plate 110. Furthermore, an openable spouting hole 114 may be provided at the top plate 110, and the spouting hole 114 is normally sealed up with a seal-up film 140 stuck separably to the exterior side of the container by means of insert injection molding or the like. Then, a energy director is provided at the heat welding part 131 wherewith the lid body 100 is welded to the container body, and the energy director is used when ultrasonic welding is applied.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a lid for a container filled with juice and other beverages, and more particularly to a pressure-resistant lid which is required to have excellent internal pressure resistance for the contents.

[0002]

2. Description of the Related Art Various types of containers are known as one-way containers for juices, soft drinks and the like. As these containers, paper containers such as paper cups are widely used, and the contents are filled in the paper containers, and the opening is sealed with a lid material. Thus, when sealing with a lid material,
At the top of the paper container, a seam portion where the paper material is overlapped remains as it is, and a step is formed, so that it is difficult to seal with good hermeticity.

In order to improve the sealing property of the lid material by sealing, a paper container in which a preformed plastic ring is adhered to the opening of the paper container by means of ultrasonic waves or the like has been proposed and put into practical use. . Furthermore, in order to protect the contents from penetrating, etc., a composite container is formed by injecting molten plastic directly into a paper container, and simultaneously forming a protective portion on a polymerization portion of the container body and a plastic ring on the top of the body. The composite container with these plastic rings has the strength of the opening and no step in the sealing part, so not only the sealing with excellent sealing performance, but also the structure in consideration of the opening property is considered. And was a container suitable for filling with a liquid.

[0004]

However, the above-mentioned composite container is a container in which a lid made of a paper sheet, a laminated film, a thermoplastic resin or the like is adhered to a plastic ring surface by heat fusion. When the main body is filled with the contents, sealed with the lid, and circulated, in the case of foamable contents, there is a problem that the lid is deformed, the welded portion is peeled off, or the bag is broken due to internal pressure expansion.

The present invention solves the above-mentioned problems of the lid of the conventional composite container, in which the deformation of the lid due to an increase or decrease in the internal pressure in the container is extremely small, and the sealing and appearance of the container are improved. Provide a good pressure-resistant lid.

[0006]

That is, the first aspect of the present invention is as follows.
As shown in FIG. 1, a lid (100) made of a thermoplastic resin for sealing a container by a heat-sealing portion (131) to a container body and a fitting portion (121) as shown in FIG. A pressure-resistant lid (100) characterized in that the top plate (110) of the body has a step (111) near the peripheral wall (120) and is convex downward.

Next, according to a second aspect of the present invention, as shown in FIG. 2, a heat-sealing portion (131) to the container body and a fitting portion (1) are provided.
21), in the lid (100) made of a thermoplastic resin for sealing the container, the top plate (110) of the lid has a step (111) near the peripheral wall (120) and protrudes downward. A pressure-resistant lid (100), which has a shape and has a groove (112) projecting downward with a groove on an upper surface at a periphery thereof.

Next, according to a third aspect of the present invention, as shown in FIG. 3, a heat-sealing portion (131) to the container body and a fitting portion (1) are provided.
21), in the lid (100) made of a thermoplastic resin for sealing the container, the top plate (110) of the lid has a step (111) near the peripheral wall (120) and protrudes downward. A pressure-resistant lid (100), which has a shape, and has a groove (113) protruding upward with a groove on a lower surface on a peripheral edge.

Next, according to a fourth aspect of the present invention, as shown in FIG. 4, a heat-sealing portion (131) to the container body and a fitting portion (1) are provided.
According to 21), in the lid (100) made of a thermoplastic resin that seals the container, the shape of the top plate (110) of the lid protrudes downward with a groove on the upper surface on the periphery near the peripheral wall (120). A pressure-resistant lid (100), wherein a groove (112) is formed.

Next, a fifth invention of the present invention will be described with reference to FIGS.
As shown in (1), the top plate (110) is a pressure-resistant lid (100) according to the first to fourth inventions, characterized in that the shape of the top plate (110) protrudes downward into a curved shape.

Next, according to a sixth aspect of the present invention, as shown in FIG. 9, a heat-sealing portion (131) to the container body and a fitting portion (1) are provided.
21), in the lid (100) made of a thermoplastic resin for sealing the container, the top plate (110) of the lid protrudes downward in a curved shape, and the pressure-resistant lid ( 100).

Next, according to a seventh aspect of the present invention, there is provided a pressure-resistant lid according to any one of the first to sixth aspects, wherein a lattice-like or annular convex rib is provided on a lower surface of the top plate. Body.

Next, according to an eighth aspect of the present invention, as shown in FIGS. 10 to 13, the shape of the top plate (110) is a waveform formed by repeating irregularities.
A pressure-resistant lid (100) according to the invention.

Next, a ninth invention of the present invention is characterized in that the top plate is provided with an opening (114) which can be opened as shown in FIG. Pressure-resistant lid (100).

Next, according to a tenth aspect of the present invention, as shown in FIGS. 1 to 13, a sealing film (140) is provided on the upper surface of the top plate (110) including the pouring holes (114). The pressure-resistant lid (100) according to any of the first to ninth aspects, wherein the lid is sealed so as to be peelable.

Next, an eleventh aspect of the present invention is the pressure-resistant lid according to the first to tenth aspects, wherein an energy director is provided in a heat-sealed portion with the container body. It is.

According to a twelfth aspect of the present invention, there is provided a pressure-resistant device according to any one of the first to eleventh aspects, wherein an occlusal unevenness or a screw is provided at a fitting position with the container body. It is a lid.

[0018]

The pressure-resistant lid (100) of the present invention, as shown in FIG. 14, is provided at the opening of the composite container with a plastic ring, which is the container body (200), with the heat-sealing part (131) and the fitting part. When the opening is sealed by mounting by (121),
When the top plate (110) of the lid is deformed so as to swell upward when the internal pressure of the container is increased by the contents, the fitting portion (121) of the lid with the container main body is pushed outward in the direction of spreading. Under the force, the fitting surface is strongly fitted to the container body. Therefore, a shearing force is not easily generated on the bonding surface of the heat-sealed portion (131) on the lower surface of the flange (130). As a result, the sealing performance of the container is good without breaking the sealing of the lid to the container body, and the vertical displacement of the top plate at this time is absorbed by the shape of the top plate and is extremely small. Also, the appearance of the lid is good even when the internal pressure is increasing.

Further, in the pressure-resistant lid of the present invention in which the reinforcing ribs are provided on the inner surface side of the lid, the deformation of the top plate can be further suppressed by the rigidity of the reinforcing ribs due to the fluctuation of the internal pressure of the container.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The thermoplastic resin used in the present invention may be selected according to the purpose of the contents and the like, and is a general-purpose resin represented by a polyolefin resin, and has low odor and low adsorption to the contents. If necessary, ethylene-vinyl alcohol copolymer resin, polyethylene terephthalate resin, polyester resin typified by polyethylene naphthalate resin, polyacrylonitrile resin or polycarbonate resin depending on the purpose, styrene resin, any of polyamide resin It may be used.

In the lid of the present invention, a reinforcing rib having a lattice shape or an annular shape may be provided on the inner surface side of the container of the top plate of the lid, and the shape of the reinforcing rib is not particularly limited. However, a rib having a rectangular, convex or L-shaped cross section may be used.

As shown in FIG. 1, an opening (114) that can be opened may be provided on the top plate (110) of the lid. Usually, the opening is formed by a sealing film (114). 140)
Is peelably adhered to the outer surface side of the container by a heat seal method, an insert injection molding method, or the like, and sealed.

The sealing film may be a laminate having heat sealing property with the lid, and when the barrier property is provided, a metal foil layer, a metal or an inorganic substance such as silicon oxide may be provided on the outer layer. This can be achieved by using at least one of a layer made of a thermoplastic resin film or paper on which is deposited, an ethylene-vinyl alcohol copolymer resin layer, a polyamide resin layer, and a polyvinylidene chloride resin layer.

Further, an energy director can be provided at the heat-sealed portion of the lid with the container body, and this can be used for ultrasonic welding.

Further, by providing the fitting irregularities or screws on the side surface and the lid of the container, the container and the lid are fitted or fitted with screws, so that a stronger pressure resistance can be obtained.

[0026]

EXAMPLES Examples of the present invention and comparative examples are shown below.

Example 1 First, a polyethylene layer (20
μm) / paper layer (320 g / m ² ) / polyethylene layer (2
0 μm) / polyethylene layer (15 μm) / polyethylene terephthalate layer (12 μm) / silicon oxide deposited film (50
0Å) / polyethylene layer (60 μm), body,
Using the bottom plate, the lower periphery of the trunk and the periphery of the bottom plate were wound in a heated state, and the trunk and the bottom plate were integrated to produce a paper container.

Next, the paper container was placed in an injection molding die, the mold was clamped, and then molten polyethylene was injected.
As shown in FIG. 4, a plastic ring (230) is formed on the top of the container body (200), and at the same time, the body (21) is formed.
A plastic protective material (240) was formed on the overlapping portion of (0) and the joint portion between the trunk portion and the bottom plate (220) to produce a composite container with a plastic ring.

Separately from this, an aluminum foil layer (50 μm) / polyethylene terephthalate (12 μm)
m) / Laminated film (45 μm) (Polyethylene layer / Polyvinylidene chloride layer / Polyethylene layer) A sealing film having a structure was placed in an injection molding die, and after clamping, the molten polyethylene was injected. As shown in FIG.
0) The shape has a step near the peripheral wall (120),
The lid (100) of the present example was produced by heat-sealing the sealing film (140) so as to be peelable on the top surface of the top plate (110) including the pouring hole (114).

Next, the carbonated beverage is filled into the above-mentioned container body by a filling machine, and the above-mentioned lid of the present embodiment is driven into the opening of the container body to fit into the container body. The heat-sealing portion (131) provided with the energy director on the lower surface of the flange (130) of the lid is heat-sealed to the heat-sealing portion on the upper surface of the container body by a sealing method to seal the content. A 250 ml composite container was obtained.

<Embodiment 2> As shown in FIG. 2, the shape of the top plate (110) of the lid is a step (1) near the peripheral wall (120).
11) A composite container having an inner capacity of 250 ml was obtained in the same manner as in Example 1 except that a groove (112) projecting downward and having a groove on the upper surface and projecting downward was formed on the periphery. Was.

<Embodiment 3> As shown in FIG. 3, the top plate (110) of the lid has a step (1) near the peripheral wall (120).
11) A composite container having an inner capacity of 250 ml was obtained in the same manner as in Example 1 except that a groove portion (113) having a downwardly convex shape and having a groove on the lower surface and projecting upward at the periphery was formed. Was.

<Embodiment 4> As shown in FIG. 4, the shape of the top plate (110) of the lid is such that a groove (112) having a groove on the upper surface and projecting downward is formed on the periphery near the peripheral wall (120). Except for this, a composite container having an internal volume of 250 ml was obtained in the same manner as in Example 1.

<Embodiment 5> The shape of the top plate (110) is shown in FIG.
As shown in FIG. 7, a composite container having an inner volume of 250 ml was prepared in the same manner as in Example 1 except that the container had a step (111) near the peripheral wall (120), and was convex downward and projected downward into a curved surface. Obtained.

<Embodiment 6> As shown in FIG. 6, the shape of the top plate (110) of the lid is a step (1) near the peripheral wall (120).
11) As in Example 1, except that the groove has a groove on the upper surface and protrudes downward at the periphery and has a groove on the upper surface, and the groove protrudes downward. A composite container having an internal volume of 250 ml was obtained.

<Embodiment 7> As shown in FIG. 7, the shape of the top plate (110) of the lid is a step (1) near the peripheral wall (120).
11) is the same as that of the first embodiment except that a groove (113) having a groove on the lower surface and protruding upward is formed on the peripheral edge, and a groove is protruded downward. A composite container having an internal volume of 250 ml was obtained.

<Eighth Embodiment> As shown in FIG. 8, the top plate (110) of the lid is formed with a groove (112) having a groove on the upper surface and projecting downward on the periphery near the peripheral wall (120). ,
A composite container having an internal volume of 250 ml was obtained in the same manner as in Example 1, except that the container was projected downward in a curved shape.

<Example 9> A composite container having an inner capacity of 250 ml was prepared in the same manner as in Example 1 except that the shape of the top plate (110) of the lid protruded downward into a curved shape as shown in FIG. Obtained.

<Embodiment 10> As shown in FIG. 10, except that the shape of the top plate (110) is an outwardly inclined waveform composed of repetitions of irregularities, the internal capacity 2
A 50 ml composite container was obtained.

<Embodiment 11> As shown in FIG. 11, except that the shape of the top plate (110) is an inwardly inclined waveform composed of repetitions of irregularities, the internal capacity 2
A 50 ml composite container was obtained.

Example 12 As shown in FIG. 12, the content of the top plate (110) was the same as in Example 1 except that the top plate (110) had a waveform in which the valleys formed by repetition of irregularities were flat. A 250 ml composite container was obtained.

<Thirteenth Embodiment> A top plate (110) is formed in the same manner as in the first embodiment except that, as shown in FIG. A composite container having an internal volume of 250 ml was obtained.

<Comparative Example 1> The shape of the top plate (110) is shown in FIG.
As shown in FIG. 5, a composite container having a content of 250 ml was obtained in the same manner as in Example 1 except that the composite container was flat.

Next, the pressure resistance of the composite containers containing 14 types of carbonated beverages sealed with the lids of the above-mentioned 13 types of examples and the lid of one type of comparative example was evaluated. In the evaluation method, ten containers were immersed in warm water at 40 ° C. for 24 hours, and the deformation state of the lid, leakage of the container liquid, and damage were confirmed. Table 1 shows the results of the evaluation of the pressure resistance.

[0045]

[Table 1]

As shown in Table 1, the evaluation results of the pressure resistance were 1
In the lids of the three examples, the deformation was extremely small, the appearance was good, the contents did not leak, the sealing was good, and there was no breakage. On the other hand, in the lid of the comparative example, the deformation was extremely large, the appearance was impaired, the contents leaked in eight pieces, and three pieces were damaged.

[0047]

The pressure-resistant lid of the present invention can be used to increase the internal pressure in a container even if it is used as a lid for containers of contents such as beverages containing carbonic acid or contents requiring heat sterilization. There is no remarkable deformation that can withstand and impair the appearance, the sealing portion is not damaged by the deformation, and the sealing property is extremely good.

[Brief description of the drawings]

FIG. 1 is a sectional view of Example 1 of a pressure-resistant lid according to the present invention.

FIG. 2 is a sectional view of a pressure-resistant lid according to a second embodiment of the present invention.

FIG. 3 is a sectional view of a pressure-resistant lid according to a third embodiment of the present invention.

FIG. 4 is a sectional view of Example 4 of a pressure-resistant lid according to the present invention.

FIG. 5 is a sectional view of Example 5 of a pressure-resistant lid according to the present invention.

FIG. 6 is a sectional view of Embodiment 6 of the pressure-resistant lid of the present invention.

FIG. 7 is a sectional view of Embodiment 7 of the pressure-resistant lid of the present invention.

FIG. 8 is a sectional view of Example 8 of the pressure-resistant lid of the present invention.

FIG. 9 is a sectional view of Example 9 of the pressure-resistant lid of the present invention.

FIG. 10 is a pressure-resistant lid according to a tenth embodiment of the present invention.
FIG.

FIG. 11 is an embodiment 11 of the pressure-resistant lid of the present invention.
FIG.

FIG. 12 is a pressure-resistant lid according to a twelfth embodiment of the present invention.
FIG.

FIG. 13 is a pressure-resistant lid according to a thirteenth embodiment of the present invention.
FIG.

FIG. 14 is an explanatory view showing a state in which the pressure-resistant lid of the present invention of FIG. 1 is attached to an opening of a composite container with a plastic ring.

FIG. 15 is a cross-sectional view of a lid of Comparative Example 1.

[Explanation of symbols]

 100 Lid 110 110 Top plate 111 Step 112, 113 Groove 114 Outflow hole 120 Peripheral wall 121 Fitting part 130 Flange 131 Heat fusion part 140 Sealing film 200: Container body 210: Body 220: Bottom plate 230: Plastic ring 240: Plastic protective material

 ────────────────────────────────────────────────── ─── Continued on front page F term (reference) 3E084 AA12 AB01 CA01 CB01 CB02 CB04 CC03 EA03 EB01 EB02 EB03 EB04 EC03 FA09 FD13 GB08 GB12 GB17 HB01 HC08 HD01 HD04 KA14 KA15 KB01 LA02 LA06 LA06 LB02

Claims (12)

[Claims] (1) A heat-sealing portion and a fitting portion with the container body,
A lid made of a thermoplastic resin for sealing a container, wherein a top plate of the lid is convex downward with a step near a peripheral wall. 2. The method according to claim 1, further comprising:
In a lid made of a thermoplastic resin for sealing a container, a top plate shape of the lid is convex downward with a step near a peripheral wall, and has a groove on an upper surface on a peripheral edge and a groove protruding downward. A pressure-resistant lid, characterized by forming: 3. A heat-sealing part and a fitting part with the container body,
In a lid made of a thermoplastic resin for sealing a container, a top plate shape of the lid is convex downward with a step near a peripheral wall, and has a groove on a lower surface on a peripheral edge and a groove protruding upward. A pressure-resistant lid, characterized by forming: 4. A heat-sealing part and a fitting part with the container body,
A pressure-resistant lid, comprising: a lid made of a thermoplastic resin for sealing a container, wherein a top plate shape of the lid has a groove on an upper surface and a groove protruding downward formed on a peripheral edge near a peripheral wall. 5. The pressure-resistant lid according to claim 1, wherein said top plate has a curved shape and protrudes downward. 6. A heat-sealing part and a fitting part with the container body,
A lid comprising a thermoplastic resin for sealing a container, wherein a top plate of the lid protrudes downward into a curved shape. 7. The pressure-resistant lid according to claim 1, wherein a lattice-like or annular convex rib is provided on a lower surface of the top plate. 8. The pressure-resistant lid according to claim 1, wherein the top plate has a waveform formed by repeating irregularities. 9. A pressure-resistant lid according to claim 1, wherein said top plate is provided with an opening capable of being opened. 10. The pressure-resistant lid according to claim 1, wherein a sealing film is releasably sealed on an upper surface of the top plate including the pouring hole. 11. An energy director is provided in a heat-sealed portion with a container body.
The described pressure-resistant lid. 12. An occlusal unevenness or a screw for screwing is provided at a fitting position with the container body.
2. The pressure-resistant lid according to 1.