JPH0213297Y2 - - Google Patents

Description

[Detailed explanation of the idea] The present invention relates to a liquid container with a pull tab.

Conventionally, metals such as aluminum and tinplate have been studied and partially used as composite container lid materials.

For example, vinyl chloride-vinyl acetate copolymer resin is used for surface treatment of aluminum and tinplate, but its poor heat resistance makes it difficult to use as a surface treatment for lids for thermal processing such as hot filling and retorts. The use of surface treatment methods has been limited to lids with pull tabs for applications that do not require a heating process. In addition, heat-resistant nitrocellulose resin was also applied, but it could not be used because of its poor water resistance.

Epoxy resins that are thermoset have strong physical properties such as not only heat resistance but also abrasion resistance, water resistance, oil resistance, etc. due to their thermal reaction effect, and can be used for a wide range of applications including hot filling and retort. Sex is a disaster,
On the other hand, it has the disadvantage that it is difficult to obtain heat-sealing strength, and it cannot be used in cases where a drinking spout is punched out from the front and a pull tab is glued because there is no suitable sealant.

In addition, even if a variety of sealants are selected and good sealing and easy-opening properties are obtained at room temperature, when filling with hot items at temperatures between 60℃ and 95℃ during hot filling (when the internal pressure becomes pressurized) ) Also, during cooling (when the internal pressure is reduced) or during retort processing at 120°C to 140°C, the pull tab peels off due to poor heat resistance of the sealant, so it has not been put into practical use yet.

The present inventor has developed a lid body made of metal such as aluminum or plastic plate treated with epoxy resin that is ideal for the lid body of composite paper containers that does not have the above-mentioned drawbacks, and that does not peel off during hot filling or retort processing. As a result of our research to develop a lid with a pull tab that would allow consumers to easily remove the pull tab material, we developed a sealant containing 30 to 60% by weight of ethylene-vinyl acetate copolymer resin on the inner surface of the pull tab material. The inventors have discovered that the above objectives can be achieved by providing a sealant layer, and have completed the present invention based on this knowledge.

That is, the gist of the present invention is a liquid container with a pull tab in which a drinking spout is opened in a part of the lid body and a pull tab material is attached to cover the drinking spout, and the lid body is made of aluminum, tin, etc. It is made of metal, and a thermosetting epoxy resin layer is provided on its surface, and a sealant layer made of a sealant containing 30 to 60% by weight of ethylene-vinyl acetate copolymer resin is provided on the inner surface of the pull tab material. , is a liquid container with a pull tab characterized in that the sealant layer is thermally bonded to the surface of the thermosetting epoxy resin layer of the lid body.

Hereinafter, the present invention will be explained in detail with reference to the drawings.

Figure 1 shows a liquid container 13 with a pull tab according to the present invention.
shows.

The lid body 1 has a base material 2 made of metal such as aluminum or tinplate, and a thermosetting epoxy resin layer 3 is provided on the surface thereof.The back surface of the lid body 1 is made of polyethylene, polypropylene, or ethylene-vinyl acetate copolymer. A heat sealing agent layer 4 made of polyester or the like is provided.

A drinking spout 5 is opened in a part of the lid body 1, and a pull tab material 6 is attached to cover the drinking spout 5.

The base material 7 of this pull tab material 6 is aluminum foil,
Ethylene-vinyl acetate copolymer, polyester,
It is made of nylon, paper, or a laminate thereof, and contains 30 to 60% by weight of ethylene-vinyl acetate copolymer resin (vinyl acetate content: 5 to 40% by weight) via an intermediate layer 8 such as polyethylene on the inner surface. In addition, a sealant layer 9 is made of a sealant containing other ingredients such as rosin, modified rosin, tackifier such as aromatic or aliphatic petroleum resin, wax such as paraffin wax, micro wax, etc.
is provided.

Furthermore, a protective film 10 made of polyethylene, polypropylene, polyester, ethylene-vinyl acetate copolymer, etc. is attached to the back side of the lid body 1 to cover the drinking spout 5. This protective film 1
0 may be omitted if there is no need to protect the punched end face of the lid.

In the figure, 11 indicates the body of the container, 12 indicates the bottom plate, and 14 indicates the contents.

Therefore, in the present invention, when the content of ethylene-vinyl acetate copolymer resin in the sealant is less than 30% by weight, sufficient heat resistance cannot be obtained, which is undesirable, and when it exceeds 60% by weight, it is undesirable. It is also undesirable because sufficient adhesive strength cannot be obtained.

Next, in the present invention, as the thermosetting epoxy resin layer, either an uncolored epoxy resin layer or a dye-colored or pigment-colored epoxy resin layer can be applied.

Furthermore, in the present invention, the drinking spout may be provided on the bottom plate instead of being provided on the lid body.

FIG. 2 shows the liquid container with a pull tab according to the present invention in an unsealed state.

As shown in this figure, the liquid container 13 with a pull tab of the present invention can be easily opened by peeling off the sealant layer 9 from the thermosetting epoxy resin layer 3 and then tearing the protective film 10.

Next, the present invention will be specifically explained with reference to Examples.

Example 1 A drinking spout was opened in a lid material with a layered structure of dye-colored epoxy resin/tinplate 130 μm/polyethylene 100 μm to form a lid body with a drinking spout, and the lid body was covered with a drinking spout from the front side and made of aluminum. A pull tab material having a layer structure of 40μ/30μ of polyethylene/30μ of sealant having the following composition was attached, and a protective film made of 100μ of polyethylene was further attached to cover the drinking spout from the back side.

(Composition of sealant) (Ethylene-vinyl acetate copolymer 40% by weight (Vinyl acetate content 10% by weight) Tatsukifiya 40% by weight Wax 20% by weight) As the container body, take into account the adhesion with the lid and apply it on the front and back. A paper cup-shaped container processed with polyethylene was used, and after filling with 93° C. warm water, the lid with the pull tab was heat-sealed to seal the container. At this time, there was no peeling and the film was good against peeling force caused by heat and increase in the inner surface. Also, the peeling force caused by the reduced pressure under cooling was good with no peeling.

When the pull tab was peeled off after cooling, it was 1000g/15mm.
Good width and ease of opening were obtained.

Example 2 Pigmented epoxy resin/aluminum
A drinking spout is opened in a lid material with a layered structure of 130μ/polypropylene 100μ to form a lid body with a drinking spout, and the lid body is covered with a drinking spout on the front side and a layer of polyester 12μ/aluminum 7μ/polypropylene 30μ/with the following composition is formed. A pull tab material with a 20μ layer of sealant was applied, and a protective film made of 100μ polypropylene was applied to cover the drinking spout from the back side.

(Composition of sealant) (Ethylene-vinyl acetate copolymer 60% by weight (Vinyl acetate content 10% by weight) Tatsukifire 35% by weight Wax 5% by weight) Considering sealing performance with the lid body as the container body, the front and back A polypropylene-treated paper cup-shaped container was filled with water at room temperature, and the lid with a pull tab was heat-sealed to seal it. Thereafter, retort treatment at 120°C for 40 minutes was performed, and the pull tab did not peel off. At this time, the adhesive strength was 600 g/15 mm width, and good ease of opening was obtained.

Example 3 Uncolored epoxy resin/Aluminum 130μ/
A lid with a spout is formed by opening a spout in a lid with a layered structure of 100μ extruded polyester, and the lid is coated with the spout from the front side, and a sealant with the following composition: 40μ polyester / 15μ aluminum / 30μ extruded polyester A pull tab material with a layer thickness of 30μ is pasted, and the spout is further covered with polyester from the back side.
A protective film made of 30 μm was attached.

(Composition of sealant) (Ethylene-vinyl acetate copolymer 55% by weight (vinyl acetate content 10% by weight) Tatsuki Fire 40% by weight Wax 5% by weight) Use a polyester blow molded product as the container body, and store at room temperature. A commercially available cola liquid was filled and the pull tab material lid was heat sealed.

After sealing, the container was shaken by hand to increase the internal pressure with carbon dioxide gas, but the pull tab did not peel off. The internal pressure at this time was measured and found to be 8 kg/cm ² .

The adhesive strength of the pull tab was 2000 g/15 mm width, and good ease of opening was obtained.

As described in detail below, the liquid container with a pull tab according to the present invention has high heat resistance, and the pull tab is bonded with sufficient strength so that it will not peel off during hot filling or retort sterilization process. It has the advantage of being able to undergo heat treatment such as sterilization and having good ease of opening.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a liquid container with a pull tab according to the present invention, and FIG. 2 is a sectional view showing the opening process of the container. DESCRIPTION OF SYMBOLS 1... Lid body, 2... Base material of the lid body, 3... Thermosetting epoxy resin layer, 4... Heat sealing agent layer, 5... Drinking spout, 6... Pull tab material, 7... Pull tab Base material of the material, 8... Intermediate layer, 9... Sealant layer, 10... Protective film, 11... Container body body, 12... Bottom plate, 13... Liquid container with pull tab, 14... Contents.

Claims (1)

[Scope of utility model registration request] A liquid container with a pull tab in which a drinking spout is opened in the lid body or a part of the bottom plate, and a pull tab material is attached to cover the drinking spout, and the lid body is made of metal such as aluminum or tin. A thermosetting epoxy resin layer is provided on the surface, and a sealant layer made of a sealant containing 30 to 60% by weight of ethylene-vinyl acetate copolymer resin is provided on the inner surface of the pull tab material. A liquid container with a pull tab characterized by being thermally bonded to the thermosetting epoxy resin layer surface of the lid body.