JPH066060Y2 - Inner seal material for container mouth sealing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention relates to an inner seal material for sealing a container mouth.

[Prior Art] Generally, an inner seal material is provided at the mouth of a container for storing powdered or granular contents such as coffee, powdered milk, seasonings, etc. in order to protect the contents from deterioration due to moisture, oxidation or the like. It is used. This inner seal material is composed of a laminate of a reseal layer (reseal layer) whose main material is an elastic sheet such as cardboard and a membrane layer (seal layer) whose main material is an aluminum foil or other metal foil, and is a cap. When the cap is removed, the reseal layer and the membrane layer are separated from each other, the reseal layer remains inside the cap, and the membrane layer remains at the mouth of the container. When it is attached to the part, the resealing layer is overlaid on the membrane layer (this membrane layer may be removed in some cases), and it has a function of preventing moisture, oxygen, etc. from reentering the inside of the container together with the cap. Fulfill.

Usually, an emulsion adhesive or the like is used to bond the membrane layer to the mouth of the container. Conventionally, as a membrane layer, for example, as described in JP-B-58-36684, JP-A-58-36685 and JP-A-59-22046, an extrusion coating layer of polyethylene is formed on the lower surface of a metal foil of an aluminum foil. It is known that glassine paper is attached. The above-mentioned glassine paper is inferior in physical strength such as tear resistance and puncture resistance when only the metal foil is used, so that it was necessary to impart those physical strengths to the membrane layer. Further, the glassine paper has a good rideability of the emulsion adhesive when the membrane layer is adhered to the container mouth portion with the emulsion adhesive, and the solvent such as water in the emulsion adhesive layer after the adhesion is removed. It was necessary for removal.

[Problems to be solved by the invention] However, in the above glassine paper, when the cap is removed and the membrane layer is peeled from the container mouth, so-called waste of paper occurs, and a part of the glassine paper remains in the container mouth and is unsightly and unclean. It was

The present invention has been made in view of the above-mentioned conventional circumstances, and when the cap is removed and the membrane layer is peeled off from the mouth of the container to open, an inner seal for sealing the mouth of the container having a layer that can be neatly peeled off without causing paper waste etc. The purpose is to provide wood.

[Means for Solving the Problems] In order to achieve the above object, an inner seal material for sealing a container mouth according to the present invention is a membrane layer having at least a moisture-proof material layer, and a resealing layer having at least an elastic sheet layer. In the inner sealing material for sealing the mouth of a container, in which the membrane layer and the resealing layer are laminated easily with each other, the lowermost layer of the membrane layer is a water-absorbent resin layer.

[Function] The solvent of the emulsion adhesive applied to the container mouth is absorbed by the water-absorbent resin layer provided in the lowermost layer of the membrane layer to solidify the emulsion adhesive and absorb water when the membrane layer is peeled off. The adhesive resin layer is peeled off at the interface with the cured emulsion adhesive layer, so that no paper waste occurs on the surface of the container mouth.

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

FIG. 1 is a sectional view of an inner seal member for sealing a container mouth according to the present invention.

On the lower surface of the moisture-proof material layer 7 such as an aluminum foil, there is provided a water-absorbent resin layer 8 coated with a coating composition containing a water-absorbent resin and a binder for fixing the water-absorbent resin to the moisture-proof material layer 7. If necessary, a printed pattern layer 5 is provided on the upper surface of the moisture-proof material layer 7, and the printed pattern layer 5 is overlaid with a release resin layer 6 made of a transparent resin having a weak affinity for polyethylene and the like. There is. The moisture-proof material layer 7, the water-absorbent resin layer 8, and optionally the printed pattern layer 5 and the release resin layer 6 constitute a membrane layer 10 of the present invention.

An adhesive prevention layer 3 is provided on the upper surface of the release resin layer 6 via a polyolefin resin layer 4 such as polyethylene, and a wax, a hot melt, an emulsion adhesive is further provided on the adhesion prevention layer 3. An elastic sheet layer 1 such as a cardboard is bonded via an adhesive layer 2 such as a solvent type adhesive. The polyolefin resin layer 4, the sticking prevention layer 3, the adhesive layer 2 and the elastic sheet layer 1 constitute the resealing layer 9 of the present invention.

The inner seal material according to the present invention is configured such that the resealing layer 9 and the membrane layer 10 can be separated between the release resin layer 6 and the polyolefin resin layer 4.

As the water-absorbent resin used to form the water-absorbent resin layer 8, any one that can absorb the solvent (water, etc.) of the emulsion adhesive is used, and the solvent is several tens to several hundred times its own weight. A conventionally known water-absorbent resin powder capable of absorbing water is preferably used. Specific examples of such a water-absorbent resin include acrylic acid-vinyl alcohol copolymer, sodium polyacrylate, modified polyethylene oxide, starch-acrylic acid copolymer and the like. Examples of the binder used in the water absorbent resin layer 8 include vinyl chloride, vinyl acetate, chlorinated polyolefin, ethylene-vinyl acetate copolymer, polyester resin and epoxy resin. The mixing ratio of the water-absorbent resin and the binder is appropriately selected in consideration of the adhesive holding power of the binder and the solvent absorption ability of the water-absorbent resin, but the weight ratio is preferably in the range of 25:75 to 60:40. Further, as a solvent for forming the coating composition by melting the water absorbent resin and the binder, for example, ethyl acetate, vinyl acetate, toluene, methyl ethyl ketone, benzene and the like are preferably used.

The moisture-proof material used for the moisture-proof material layer 7 is preferably one that prevents moisture and oxygen from permeating into the container. For example, the aluminum foil described above, an aluminum foil reinforced with polyethylene terephthalate, or silicon oxide. Alternatively, polyethylene terephthalate, nylon, or the like in which aluminum oxide is vapor-deposited at 50 to 1000 liters is used.

The release resin layer 6 is provided to improve the releasability from the resealing layer 9, and examples of the material used for this layer include a nitrocellulose-based resin having a low affinity for polyethylene, a polyamide-based resin, An acrylic resin, a rubber resin, an ester resin, a urethane resin, a vinyl chloride resin, or the like, or a mixture thereof, or a composition obtained by adding a silicone resin or silica powder to the resin alone or a mixture thereof is preferable.

As a material used for the elastic sheet layer 1 constituting the resealing layer 9, when an inner seal material is attached to the mouth portion of the container,
Any material as long as the membrane layer 10 is uniformly pressed against the container opening and the resealing layer 9 can be completely adhered to the container opening even when the membrane layer 10 is removed and a cap is capped. However, elastic materials such as thick cardboard, cardboard, expanded polystyrene, expanded polyurethane and expanded polyethylene are preferable.

The adhesion-preventing layer 3 constituting the resealing layer 9 prevents the polyolefin-based resin layer 4 from sticking to the cooling roll and peeling off when the polyolefin-based resin layer 4 is extrusion-coated.
It is provided to stabilize the extrusion coating step, and at the melting temperature of the resin used for the polyolefin-based resin layer, stretched or unstretched polyethylene, polypropylene, polyvinylidene chloride, nylon, or the like that does not exhibit fusion bonding properties. A plastic film is used. The anti-adhesion layer 3 is laminated after the polyolefin resin layer 4 is extrusion coated on the release resin layer 6 and before the polyolefin resin layer 4 is cooled.

FIG. 2 shows that the inner seal material is loaded into the cap,
It is sectional drawing which showed the state which put this cap on the container opening part. In the figure, 11 is a cap, 12 is a container body,
Reference numeral 13 is a cap side portion, 14 is a rib formed inside the cap side portion, 15 is a container neck portion, 16 is a screw thread on the outer surface of the container neck portion, and 17 is a screw thread inside the cap side portion. When the cap 11 is attached to the mouth of the container, the inner seal material in the cap 11 is adhered to the mouth of the container due to the elasticity of the elastic sheet.

FIG. 3 is a cross-sectional view showing a state in which the cap 11 is removed from the container body 12 and the inner sealing material is separated into the resealing layer 9 and the membrane layer 10. When the cap 11 is removed, peeling occurs between the polyolefin resin layer 4 and the release resin layer 6, and the resealing layer 9 is built in the cap and the membrane layer 10 is removed.
Remains at the mouth of the container. When the membrane layer 10 is pulled upward in this state, peeling occurs between the emulsion adhesive 18 applied to the mouth of the container and the water absorbent resin layer 8. The membrane layer 10 may be removed from the container opening,
It may be left as it is at the container mouth. When the cap 11 is again attached to the container opening after removing the membrane layer 10, the elasticity of the elastic sheet layer 1 can seal the container opening.

Next, a method of manufacturing the inner sealing material for sealing the container mouth portion according to the present invention will be described with reference to FIG.

A web of aluminum foil is unwound from a roll of aluminum foil (moisture-proof material), and the surface on which the printed pattern layer 5 is provided by gravure printing or the like is coated with a nitrocellulose resin to form a release resin layer 6. Next, the surface of the aluminum foil opposite to the surface coated with the release resin layer 6 is coated with a water absorbent resin coating composition containing a water absorbent resin to form a water absorbent resin layer 8. Subsequently, the release resin layer 6 is melt-extruded and coated with polyethylene to form a polyolefin resin layer 4, and before the resin layer 4 is solidified, a plastic film such as stretched polyethylene is laminated and the laminated film 19 is rolled. To create. The laminated film 1
The web of the laminated film 19 is unwound from the roll 20 of 9 and fed to the roll coater 21.
An adhesive such as wax is applied onto the plastic film of the web of No. 9. On the other hand, an elastic sheet is unrolled from an elastic sheet roll 22 such as cardboard and brought into contact with the adhesive-coated surface of the plastic film, which is pressed by a pressing roller 23 to form a laminate 24, which is then run horizontally. The sheet 26 is cut by the cutting machine 25 while being allowed to move. Next, the sheet 26 is punched out into a circular shape having a diameter corresponding to the inner diameter of the cap to obtain the inner seal material according to the present invention as the final product.

[Effects of the Invention] As described in detail above, according to the inner sealing material for sealing the container mouth of the present invention, since the water-absorbent resin layer made of a water-absorbent resin is provided as the lowermost layer of the membrane layer, the emulsion adhesive The glassine paper for absorbing the solvent therein was not required, and when the membrane layer was peeled off at the time of use, so-called paper waste did not occur, and it could be peeled off beautifully and neatly. For this reason, when the cap is removed after repeated use, the result is a clean feeling and a good impression. Further, although the inner seal material was completely sealed as before, the membrane layer was easily peeled off after removing the cap.
Furthermore, since it is not necessary to attach glassine paper, the manufacturing process is simplified.

The inner sealing material for sealing the container mouth of the present invention uses a moisture-proof material having a high gas barrier property, such as oxygen, which has a moisture permeation-preventing ability, so that the deterioration of the contents can be prevented.

[Brief description of drawings]

FIG. 1 is a sectional view of an inner seal material for sealing a container mouth according to the present invention, and FIG. 2 is a sectional view showing a state in which the inner seal material is loaded in a cap and the cap is capped on the container mouth. FIG. 3 is a sectional view showing a state in which the resealing layer remains inside the cap and the membrane layer remains at the mouth of the container when the cap is removed from the container body, and FIG. 4 shows the manufacturing process of the inner seal material of the present invention. It is a schematic diagram. DESCRIPTION OF SYMBOLS 1 ... Elastic sheet layer, 2 ... Adhesive layer 3, Adhesion prevention layer, 4 ... Polyolefin resin layer 5 ... Printing pattern layer, 6 ... Release resin layer 7 ... Moisture-proof material layer, 8 ... Water-absorbent resin layer 9 ... Re-sealing layer, 10 ... Membrane layer 11 ... Cap, 12 ... Container body 13 ... Cap side part 14 ... Ribs projecting inside cap side part 15 ... Container neck part, 16 ... Thread on outer surface of container neck 17 ... Cap side Internal screw threads 18 ... Emulsion adhesive 19 ... Laminated film, 20 ... Roll 21 ... Roll coater, 22 ... Elastic sheet roll 23 ... Crimping roller, 25 ... Cutting machine

Claims (1)

[Scope of utility model registration request] 1. A container for sealing the mouth of a container, which comprises a membrane layer having at least a moisture-proof material layer and a resealing layer having at least an elastic sheet layer, and the membrane layer and the resealing layer are laminated to facilitate peeling. In the inner seal material, the lowermost layer of the membrane layer is made of a water-absorbent resin layer.