BACKGROUND OF THE INVENTION
Field of the Invention
[0001] This invention relates to a tightly sealed paper container provided with a simplified
opening device.
Related Art Statement
Description of the Prior Art
[0002] As opening devices secured to tightly sealed paper containers, there have heretofore
been known one in which a pull tab piece made of aluminium foil covering an opening
is secured to the top surface of a container formed with the opening at a predetermined
position thereof, another one in which a lining member made of synthetic resin and
formed therein with a small through hole is bonded to the rear surface of the container
formed with an opening at a predetermined position thereof such that the small through
hole is positioned in the opening and a pull tab piece covering the opening is secured
to the front surface of the container, and a further one consisting of a main body
of pour-out member including a pour-out tube and a flange portion, and a cap inserted
into the forward end of the pour-out tube, wherein the flange portion of the main
body of pour-out member is bonded to the peripheral wall of the opening of the container.
[0003] Out of the conventional opening devices described above, in the one in which the
pull tab piece covering the opening is secured to the front surface of the container,
the section of the opening is liable to be irregular in form due to torn laminated
resin, whereby inconvenience is experienced with the pour-out operation and it is
unable to reseal after the opening operation.
[0004] Furthermore, in another one in which the lining member is bonded to the rear surface
of the container formed with the opening and the pull tab piece covering the opening
is secured to the top surface of the container, it is unable to reseal after the opening
operation.
[0005] In the last one in which the flange portion of the main body of pour-out member including
the pour-out tube and the flange portion is bonded to the peripheral wall of the opening
of the container, the opening device is protruded from the container, whereby the
height thereof serves an obstacle, as that handling of a carton and assembling of
the container on a fill-up and tight-seal device come to be complicated. Moreover,
the opening device is of a complicated shape, so that the opening device cannot be
fully exposed to a hydrogen peroxide gas at the time of sterilizing the inner surface
of the container prior to fill-up of the content, or there is a possibility that the
gas remains in the opening device.
SUMMARY OF THE INVENTION
[0006] The present invention has been developed to obviate the disadvantages of the above-described
conventional opening device.
[0007] To this end, the present invention has adopted such an arrangement that a through
hole is formed in a container material laminated with thermoplastic synthetic resin
layers provided on the front and rear surfaces thereof, a bottom board made of the
thermoplastic synthetic resin and having a through hole equal in size to or smaller
than the aforesaid through hole is bonded to the front surface of the container such
that the whole of the through hole of the bottom board coincides with the through
hole of the container material or is positioned within the contour of the through
hole of the container material, a top board made of the thermoplastic synthetic resin
and having a coupling projection, the outer periphery of which is at least partilly
coupled in pressure contact into the inner wall of the through hole of the bottom
board, is superposed on the bottom board with the coupling projection coupled into
the through hole of the bottom board, further, a barrier film covering the trough
hole of the container material is laminated on the rear surface of the container,
and the barrier film is bonded to the rear surface of container and the top surface
of the coupling projection coupled into the through hole of the bottom board.
[0008] The through hole formed in the container material is covered with the barrier film
bonded to the rear surface of the container. This barrier film is bonded to the top
surface of the coupling projection of the top board superposed on the bottom board
bonded to the front surface of the container through the through hole of the container
material and the through hole of the bottom board, whereby, when the top board is
pulled up from the bottom boaed, a portion of the barrier film bonded to the top surface
of the coupling projection of the top board is cut away, so that the through hole
of the container material is opened.
[0009] When the top board pulled up from the bottom board as described above is superposed
on the bottom board with the coupling projection of the top board coupled into the
through hole of the bottom board, the outer periphery of the coupling projection is
brought into pressure contact with the inner wall of the through hole of the bottom
board to be held in a coupling state, whereby the through hole which has been opened
is sealed.
[0010] The protrusion from the container material is as very small as the combined thicknesses
of the top board and the bottom board, so that there is no trouble for forming the
container material secured thereto with the aforesaid opening device into a carton
and handling of the carton, assembling of the container on the fill-up and tight-seal
device and fill-up of the content can be performed without any trouble. Further, the
container is so simple in construction that it has no pour-out tube portion, so that,
at the time of sterilizing with the hydrogen peroxide gas, there are no possibilities
that any portion is left unexposed to the hydrogen peroxide gas and the gas remains
in the opening device.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
Fig. 1 is a perspective view showing an embodiment of the present invention;
Fig. 2 is an enlarged sectional view taken along the line in Fig. 1;
Fig.3 is an enlarged perspective view showing the bottom board and the top board as
illustrated in Fig. 1;
Fig. 4 is an explanatory view showing a state where the top board is pulled upwardly
to open the container; and
Fig. 5 is a sectional view of essential portions showing another embodiment.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] The present invention will hereunder be described in detail with reference to embodiments
shown in the drawings.
[0013] Referring to the drawings, designated at reference numeral 1 is a main body of paper
container and 2 a container material forming the main body of paper container 1. This
container material 2 is formed of a laminated body in which layers 4, 5 made of thermoplastic
synthetic resin such as polyethylene and polypropylene are laminated on the outermost
layers of the front and rear surfaces of a paper board 3, and, as necessary, a reinforcing
layer such as an aluminium foil layer and a synthetic resin layer of barrier property
is laminated on a substrate thereof. Denoted at 6 is a through hole formed in the
container material 2 positioned at a top wall 7 of the main body of paper container
1.
[0014] Designated at 8 is a bottom board made of synthetic resin bonded to the front surface
of the container material 2 formed therein with a through hole 6. This bottom board
8 is formed therein with the through hole 9 smaller in size than the through hole
6 formed in the container material 2. A raised wall 10 having substantially the same
height as the thickness of the container material 2 is provided along the contour
of the aforesaid through hole 9 in a tubular shape on the side of the surface of the
bottom board 8, to which the container material 2 is bonded. The bottom board 8 with
this arrangement is bonded to the front surface of the container material 2 with the
tubular raised wall 10 inserted into the through hole 6 of the container material
2. Thus, the through hole 9 of the bottom board 8 bonded to the front surface of the
container material 2 is positioned within the contour of the through hole 6 of the
container material 2.
[0015] Denoted at 11 is a top board made of synthetic resin superposed on the bottom board
8. This top board 11 is formed with a coupling projection 12, the outer periphery
of which is at least partially coupled in pressure contact into the inner wall of
the through hole 9. In the embodiment illustrated, pressure contact projections 13
coming into pressure contact with the outer periphery of coupling projection 12 of
the top board 11 are formed on the inner wall of the through hole 9 of the bottom
board 8. However, the present invention should not necessarily be limited to this,
and pressure contact projections may be formed on the outer periphery of the coupling
projection 12 of the top board 11, or the outer periphery of the coupling projection
12 of the top board 11 may be brought into pressure contact with the entire circumference
of the inner wall of the through hole 9 of the bottom board 8, for example. The pressure
contact may be permitted to the extent where, at least, the coupling projection 12
coupled into the through hole 9 is not easily drawn out therefrom. The top board 11
with this arrangement is superposed on the bottom board 8 bonded to the front surface
of the container material 2 with the coupling projection 12 coupled into the through
hole 9. Thus, the top surface of the coupling projection 12 of the top board 11 is
exposed to the interior of the main body of paper container 1 through the through
hole 9 and the through hole 6 of container material 2.
[0016] Further, a barrier film 14 made of aluminium foil or the like covering the through
hole 6 of the container material 2 is laminated on the rear surface of the container
material 2 is bonded to the top surface of the coupling projection 12 of the top board
11, which is exposed through the rear surface of the container material 2 and the
through hole 6.
[0017] In this embodiment, the upper end of the top board 11 is rockably connected to the
upper end of the bottom board 8. Furthermore, the lower end of the bottom board 8
curves upwardly, whereby an apron 15 is formed to avoid saggs of liquid. A ring-shaped
tag 16 is provided at the lower portion of the top board 11. The shape of this tag
16 should not be limited to a specific one, and any shape easily be held may be adopted.
[0018] Fig. 5 shows another embodiment, in which the through hole 6 formed in the container
material 2 is equal in size to the through hole 9 formed in the bottom board 8, whereby
the bottom board 8 is bonded to the front surface of the container material 2 with
the through hole 9 of the bottom board 8 coinciding with the through hole 6 of the
container material 2.
[0019] Incidentally, according to the present invention, the barrier film 14 may be laminated
on the rear surface of the paper board 3 forming the container material 2, whereby
the thermoplastic synthetic resin layer 5 having as its substrate the reinforcing
layer such as the synthetic resin layer of the barrier properties is utilized as it
is.
[0020] As described hereinabove, according to the present invention, for opening the container,
by a simple means of merely pulling up the top board from the bottom board, part of
the barrier film bonded to the top surface of the coupling projection of the toy board
is cut away to open the through hole of the container material, so that the container
can be opened. The top board which has been pulled up is superposed on the bottom
board and the coupling projection of the top board is coupled into the through hole
of the bottom board, so that the container can be easily resealed.
[0021] Further, the protrusion from the container material is as very small as the combined
thicknesses of the top board and bottom board, so that there is no trouble for forming
the container material secured thereto with the aforesaid opening device into the
carton, and handling of the carton, assembling of the container on the fill-up and
tight-seal device and fill-up of the contact can be easily performed without requiring
special reconstruction and installation of additional equipment.
[0022] Furthermore, the opening device is so simple as to have no pour-out tube portion,
so that sterilizing with the hydrogen peroxide gas can be easily performed and the
hydrogen peroxide gas can be easily removed after the sterilization.
[0023] Moreover, the mechanical strength around the through hole of the container material
can be reinforced with the bottom board and saggs of liquid can be prevented from
occurring.
1. A tightly sealed paper container, wherein a through hole (6) is formed in a container
material (3) laminated with thermoplastic synthetic resin layers (4,5) provided on
the front and rear surfaces thereof, characterized by a bottom board (8) made of thermoplastic
synthetic resin and having a through hole (9) equal in size to or smaller than said
through hole (6) in the container material (3), is bonded to the front surface of
the container such that the whole of the through hole (9) of the bottom board (8)
coincides with the through hole (6) of the container material or is positioned within
the contour of the through hole (6) of the container material; a top board (11) made
of thermoplastic synthetic resin and having a coupling projection (12), the outer
periphery of which is at least partially coupled in pressure contact with the inner
wall of the through hole (9) of the bottom board (8), the top board being superposed
on the bottom board (8) with said coupling projection (12) coupled into the through
hole (9) of the bottom board (8); and a barrier film (14) covering the through hole
(6) of the container material (3) and laminated on the rear surface of the container
(2), said barrier film (14) being sealed with respect to the rear surface of the container
material and to the top surface of the coupling projection (12) coupled into the through
hole (9) of the bottom board (8).
2. A container according to Claim 1, wherein said bottom board (8) has an upstanding
tubular projection (10) which engages within said through hole (6) of the container
material (3), the inner periphery of said tubular projection (10) providing said through
hole (9) in which said coupling projection (12) engages.
3. A container according to Claim 2, wherein pressure contact projections (13) are provided
on the inner periphery of said tubular projection (10) to bear against said coupling
projection (12) when engaged in said through hole (9).
4. A container according to any one of Claims 1 - 3 wherein said coupling projection
(12) is provided with pressure contact projections on its outer periphery.
5. A container according to any one of Claims 1 - 4 wherein said top board (11) is pivotally
connected to said bottom board (8) at one pair of corresponding upper ends thereof.
6. A container according to any one of Claims 1 - 5 wherein the lower end of the bottom
board (8) curves upwardly away from said front surface of the container.
7. A container according to any one of Claims 1 - 6 wherein the lower end of the upper
board (11) is formed as a ring-like tag (16).