JPH0236468B2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to the improvement of a sealed container consisting of a container body and a cover whose main strength is paper. A container body formed of a laminated sheet containing a container body and a cover lid can be easily fitted and sealed by heat sealing, and the sealed cover lid can be easily opened without causing deformation or damage, and is suitable for re-closing. This is what made it possible.

[Conventional technology]

Conventionally, it has been extremely common practice to form containers using a laminated material made from an appropriate combination of plastic, paper, metal foil, etc., and to heat-seal the lid after filling the container with food or other contents. In the case of so-called paper containers whose main strength material is paper,
In particular, for containers that use a cover lid that fits over the opening surface of the container, it is relatively difficult to heat-seal the opening surface of the container and the bottom surface of the lid, and the heat-sealing may impair the ease of opening the lid. Often, the strength of the seal exceeds the strength of the cover, requiring a considerable amount of force to open the cover, and the cover is likely to deform or break, resulting in the disadvantage that it loses its function as a cover afterward. .

On the other hand, one of the inventors previously proposed that the opening flange of the container body be used as a means to balance the sealability and unsealability when heat-sealing a sheet-like lid to the opening edge of the container body. proposed a laminated structure in which an adhesion inhibitor layer was interposed between a surface plastic layer and an underlying paper layer (see Japanese Utility Model Publication No. 21407/1983).

[Problem to be solved by the invention]

In paper containers whose main strength material is paper, it is relatively difficult to seal the lid that fits onto the container body, and even if it is heat-sealed, it is difficult to open the lid to avoid deformation or damage. It is difficult to close the lid, and in order to open the lid so that it can be reused, it is necessary to use a lid that is stronger than usual. Because of the difficulty of sealing, heat sealing of the lids of flap-lid paper containers has generally not been performed.

[Another means to solve the problem]

The present invention provides a sealed paper container with a cover lid that can be re-closed and used by balancing heat-sealing sealability and easy-open lid property in a cover-lid sealed container using paper as the main strength material.

That is, the present invention includes a container body formed of a laminated sheet using paper as the main strength material and having a heat-adhesive plastic layer on one or both sides, and a short cylindrical lid on the periphery of a lid face plate made of the same laminated sheet. In a sealed paper container consisting of a cover lid having a flange, a protruding flange is provided on the opening edge of the container body, and the upper edge of the peripheral wall of the container body is tightened and pushed out in the outer circumferential direction. It has an adhesion inhibitor band layer interposed between the heat-adhesive plastic layer on the upper surface of the collar and the layer below it, and the laminated sheet portion with the plastic layer interposed is pressed upward over the entire circumference of the upper surface of the collar. The gist of the present invention is a heat-sealable cover-lid sealed paper container characterized by having a thin annular protrusion formed by extrusion.

The above-mentioned container body is made by wrapping the upper edge of the peripheral wall of the opening edge inwardly or outwardly, and squeezing the tightened portion so as to extend toward the outer circumference of the container, so that a heat-adhesive plastic layer is formed on the top surface. Therefore, if the container body is manufactured from a laminated sheet having a heat-adhesive plastic layer on only one side of the paper layer, the container can be wrapped in the above-mentioned direction. Either the outer surface or the inner surface of the peripheral wall of the main body is a thermoadhesive plastic layer surface. In addition, the adhesion inhibitor band layer interposed between the heat-adhesive plastic layer on the upper surface of the protruding flange and its lower layer is printed in the required area during the laminated sheet manufacturing process, and the adhesion inhibitor band is applied to the protruding flange of the container body. The protruding flange may occupy all or a part of the upper surface width and exist in an annular shape around the entire circumference of the flange, and the adhesion inhibitor band layer may be interposed in the protruding flange when it is rolled and extruded. The laminated sheet portion is extrusion-molded to form annular protrusions with a width equal to or less than the width of the upper surface of the flange.

[Effect]

In the sealed paper container of the present invention, the shape-retaining strength of the container body is increased by the protruding flange that is wrapped and pressed around the opening edge of the container body, and the lid is fitted onto the protruding flange for stable closure. Along with the things that are
By bringing the back surface of the face plate of the cover lid into contact with the top surface of the narrow annular convex strip of the protruding flange and heating and pressing, it is possible to completely and easily fuse and seal a relatively small area of the heat-adhesive plastic layer. When the above-mentioned sealed cover lid is slightly twisted and rotated with respect to the container body, the heat-adhesive plastic layer portion bonded to the lid surface with a narrow cloth is separated from the adhesion inhibitor band layer surface. By lifting the lid, the thin heat-adhesive plastic layer stretches and breaks.
The cover can be easily opened without deforming the cover.

Therefore, the opened cover can be repeatedly applied to the container body.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

1, 2, and 3 show a first embodiment, in which the container body 10 has a bottom 19, and the upper edge of the peripheral wall 11 is rolled outward and press-formed in the outer circumferential direction. A protruding collar 8 is provided.

Reference numeral 20 denotes a cover, which has a short cylindrical lid flange 26 on the periphery of the lid plate 21, and is slightly elastically fitted and covered on the outer periphery of the protruding flange 8 on the upper edge of the container body 10. It's becoming like that.

After storing the liquid or solid content in the container body 10, with the lid 20 fitted and covered, the lower surface of the lid plate 21 is pressed against the container by applying pressure from the upper surface of the lid plate 21 with the heating pressing member. The annular protrusion 9 protruding from the entire circumference of the upper surface of the protruding collar 8 of the main body 10 is heat-sealed as described below under pressure contact.

As shown in FIGS. 2 and 6, the peripheral wall 11 of the container body 10 is made by coating or laminating heat-adhesive plastic layers 3, 4 such as polyethylene or polyvinyl chloride on both sides of a slightly thick paper layer 2. It is formed from a laminated sheet 1. FIG. 5 is a plan view of a blank plate for forming the peripheral wall 11 of the container body 10, and the protruding collar 8 of the container body 10 is wound around the upper edge portion 18 of the blank plate for forming the peripheral wall 11 of the container body 10. In the area including the annular protruding strip 9 provided around the entire circumference, there is a layer between the thermoadhesive plastic layer 3 on the upper surface of the collar and the paper layer 2 on the lower surface, as shown in FIGS. An adhesion inhibitor band layer 7 such as the above is printed and coated.

As the adhesion inhibitor, polyamide, polyurethane, nitrified cotton, silicone, etc. are appropriately selected. Note that 17 is an adhesive allowance for forming the peripheral wall. The lid 20 also has a lid plate 21 formed by laminating a heat-adhesive plastic layer 23 on the lower surface of a slightly thick paper layer 22 and an appropriate plastic layer 24 on the upper surface, and extends the outer peripheral edge of the lid plate 21 downward. A bent peripheral edge 25 is press-formed, and a short paper cylinder 28 having a rolled-up edge 27 formed on the upper edge to protrude inward is fitted onto the outer surface of the bent peripheral edge 25, and the lower edge thereof is folded back onto the inner surface of the bent peripheral edge 25. The inner wall 29 is press-molded, and thus,
The lid face plate 21 is held by the lid flange 26 which is reinforced by a short paper cylinder 28 that surrounds the bent periphery 25 in a laminated manner, and the fitted state shown in FIG. The inner wall 29 surface of the lid flange 26 is elastically fitted, and the lower surface of the lid face plate 21 and the upper surface of the annular protrusion 9 of the protruding flange 8 abut, as shown in FIG. The protruding end 31 is pressed and heated to fuse and seal the two heat-adhesive plastic layers 23, 3.

The cover lid 20 that has been sealed in this manner is opened by slightly twisting the lid flange 26 against the container body 10 and then peeling it off. The fused portion between the nine surfaces peels off from the adhesion inhibitor band layer 7 surface interposed on the lower surface of the thermoadhesive plastic layer 3 of the protruding flange 8, causing elongation rupture of the weak plastic layer 3 itself. The cover 20 can be easily separated and opened.

Therefore, the cover 20 can be fitted onto the container body 10 again without leaving any deformation or strain.

FIG. 4 shows an inner wrapping tightening protruding flange 8' instead of the outer wrapping tightening protruding flange 8 provided on the container body 10 in the first embodiment, and a narrow annular protruding strip 9 on the upper surface of the flange. This shows a second embodiment provided, which has the same effect as the first embodiment.

FIG. 8 shows that the protruding flange 8'' of the container body 10 is formed by folding back, the annular protruding strip 9 is press-molded, and the adhesion inhibitor band layer 7 is formed under the thermoadhesive plastic layer 3 of the annular protruding strip 9. This figure shows the third embodiment in which the protruding flange of the present invention is tightened, and is fully practicable depending on the strength of the laminated sheet, the conditions of use, and the design of the container. This also includes cases where bent and overlapped edges are used.

Furthermore, for the lid face plate 21 of the cover lid 20, a laminated sheet containing aluminum foil can also be used as appropriate.

In the above description, the container body 10 and the cover lid 2
Although a case is shown in which a heat mold plate is used as a means for thermally adhering to 0, it goes without saying that other known heat sealing means such as ultrasonic heating, high frequency heating, etc. can also be applied.

〔Effect of the invention〕

As explained above, the present invention uses paper as the main strength material and a sheet made of heat-adhesive plastic to form a heat-sealable sealed container using a container body and a cover lid. A reinforcing protruding flange is provided on the edge, and the upper surface of the narrow annular protrusion formed on the upper surface of the flange is used as a heat-sealing surface,
An adhesion inhibitor layer is interposed on the lower surface of the heat-adhesive plastic layer on the surface to maintain a balance between sufficient sealing performance and easy opening, allowing the lid to be opened without deforming the lid. Since the lid can be put on again, an extremely desirable container can be obtained, especially as a sealed container for ice cream and other foods.

[Brief explanation of drawings]

The drawings show embodiments of the present invention.
The figure is a side view showing the first embodiment with a part cut away, FIG. 2 is an enlarged sectional view showing a part of the same essential part, and FIG. 3 is a perspective view showing a part cut away. Fourth
The figure is a perspective view of the container main body of the second embodiment, FIG. 5 is a plan view of the peripheral wall blank plate of the container main body, and FIG.
FIG. 7 is a partially cut-away side view of the lid during the sealing process, and FIG. 8 is a cross-sectional side view of the main part of the container body in the third embodiment. DESCRIPTION OF SYMBOLS 1... Laminated sheet, 2... Paper layer, 3, 4... Plastic layer, 7... Adhesion inhibitor band layer, 8, 8',
8″...Protruding collar, 9...Annular convex strip, 10...Container body, 11...Peripheral wall, 20...Cover lid, 21...
... Lid face plate, 25 ... Bent periphery, 26 ... Lid tsuba, 2
7... Rolling edge, 28... Short paper tube, 29... Folding edge, 30... Pressing member, 32... Projecting edge.

Claims (1)

[Claims] 1 A container body 10 formed of a laminated sheet 1 having a paper layer 2 as the main strength material and a heat-adhesive plastic layer 3 on one or both sides thereof, and a lid face plate 21 made of a similar laminated sheet, with a short cylindrical shape on the periphery. In a sealed paper container consisting of a cover lid 20 having a lid flange 26, a protruding flange 8 is provided on the opening edge of the container body 10, and the upper edge of the peripheral wall 11 of the container body 10 is wrapped tightly and pushed out in the outer circumferential direction. 8 has an adhesion inhibitor band layer 7 interposed between the heat-adhesive plastic layer 3 on the top surface of the collar and the layer below it, and the adhesion inhibitor band layer 7 is interposed in the laminated sheet. A heat-sealable cover-lid sealed paper container characterized in that a portion thereof has a narrow annular protrusion 9 extruded upwardly over the entire circumference of the upper surface of the brim.