JP4263299B2 - Seat lid and container provided with the same - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to instant food containers such as cup noodles. In more detail, it is related with the sheet | seat material used as a cover material of such a container.
[0002]
[Prior art]
In instant ramen containing cups, noodles and utensils are often housed in a cup-shaped container body made of expanded polystyrene or the like, and a sheet material as a lid is thermally bonded to the noodles and utensils.
[0003]
In order to cook such cup noodles, first, the lid is slightly peeled off, hot water is poured therefrom, the lid is covered again, and a predetermined time is waited. When cooking is complete, finally remove all the lids and eat ramen.
[0004]
Here, in conventional cup noodles, the lid is thermally bonded with a certain strength over the entire outer edge flange on the upper surface of the cup body, so if the lid is pulled inadvertently, the lid is peeled off all at once. It is easy to happen. In this case, it is troublesome to pour hot water first and then cover again. In other words, if a part of the lid is still fixed to the cup body, place the part that has been partially peeled off on the cup body again, and place a stir to hold only that part from above. The lid can be closed again. On the other hand, if the entire lid material is carelessly peeled off, the lid material that has been peeled off is lined up with the top surface of the cup body, and a worm to hold down the entire surface is prepared, or a separate lid material is provided. Troublesome work such as preparing
[0005]
Also, in the case of things that need to throw away the hot water poured first, such as cup fried noodles, the lid material has a hot water cut, so if you inadvertently peel off all the lid material first, Even bigger.
[0006]
[Problems to be solved by the invention]
Therefore, the technical problem to be solved by the present invention is that, in the cup container with a sheet lid used for instant foods and the like, even if the sheet lid is pulled unintentionally, the sheet lid is inadvertently peeled off. It is to reduce.
[0007]
[Means / Actions / Effects to Solve Problems]
The present invention has been made to effectively solve the above-described problems, and provides a seat lid having the following features.
[0008]
That is, the sheet lid of the present invention is thermally bonded to the opening edge of the cup-shaped container body, and is peeled off from the container body by pulling the opening tab provided in itself. And at least the “region in the vicinity of the unsealing tab” of the thermal bonding portion that contacts the opening edge of the back surface of the sheet lid is composed of “a weak heat seal layer having a relatively weak adhesive force”. In addition, “other parts” are constituted by “a strong heat seal layer having a relatively strong adhesive force”. In this way, the thermal bonding area on the back surface of the sheet lid is divided into two, and the adhesive force in the area including the opening tab is relatively reduced. And the area of the area where the weak heat seal layer is provided in the vicinity of the opening tab is “the opening formed when the opening tab is pulled and only the portion with relatively weak adhesive force is peeled off from there. The size is set so that there is no problem in pouring hot water inside. "
[0009]
In the cup noodle container manufactured using the sheet lid of the present invention having the above-described configuration, a small opening for pouring hot water first can be provided with a small force by pulling the opening tab. However, when an opening large enough to pour hot water is formed, the opening tab's resistance to tension increases. Therefore, even when the opening tab is pulled unintentionally, it is difficult to cause the inconvenience that the entire sheet lid is carelessly peeled off as in the prior art.
[0010]
The difference in adhesive strength between the strong heat seal layer and the weak heat seal layer is preferably achieved by the difference in the sealant component constituting each layer. In that case, the sealing process by the seal bar can be performed in a lump without being performed in parts corresponding to the respective heat seal layers.
[0011]
The configuration of the present invention is useful even in the case of instant noodles that do not throw away hot water poured first, but in the case of instant yakisoba, etc., a hot water cut-off for throwing out hot water poured first is used. This is particularly advantageous in the case of a provided seat lid. In the case of a sheet lid provided with a hot water cut, only when a part of the sheet lid is fixed to the container body, the hot water cut works effectively by tilting the container. This is because once it is peeled off, it can no longer function as a hot water cut. The position where the hot water cut is formed is desirably opposite to the position where the opening for first pouring hot water is formed, that is, in the vicinity of the region actually fixed to the container body.
[0012]
In the present invention, the configuration of the hot water cut itself is not particularly limited, but as described below, the hot water cut opening may be configured to be exposed by peeling off the hot water cut exposure tab. That is, the sheet lid itself is formed by laminating an upper lid layer and a lower lid layer, and a hot water outlet exposure tab is defined as “a lower tab layer in which a part of the lower lid layer is partitioned by a cut” and “sheet lid. A portion extending wider than the lower tab layer inwardly is formed from an upper tab layer formed by dividing the upper lid layer by a slit. Then, the hot water cut opening is formed in the lower lid layer so that the hot water cut opening is exposed to the lower lid layer covered with the upper tab layer by peeling off the hot water cut exposure tab.
[0013]
If such a hot water cut is used, the hot water cut will be sealed until the hot water cut exposure tab is peeled off, so it is effective for the heat to escape outside while pouring hot water. In addition, the smell does not leak out.
[0014]
DETAILED DESCRIPTION OF THE INVENTION
Embodiments of the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a perspective view showing a cup noodle container according to the present invention in a state where a part of its sheet lid is peeled off (illustration of contents is omitted). The cup noodle container 1 is composed of a container main body 20 made of expanded polystyrene or the like and a sheet lid 10 that is thermally bonded to the upper end surface of the main body 20 in the same manner as conventionally known. The sheet lid 10 has a substantially circular shape with an opening tab 11 provided at one end, and is thermally bonded to the flange portion 21 of the container body 20 at the outer peripheral end of the back surface.
[0015]
The cup noodle container 1 of the present invention is difficult to distinguish from the conventional one in terms of appearance, but the method of bonding the sheet lid 10 and the container body 20 is different from the conventional one. This will be described with reference to FIGS. FIG. 2 is a plan view showing the back surface of the sheet lid 10 bonded to the container body side. A broken line 21a indicates an inner edge of the container body flange portion 21. 3 is a cross-sectional view taken along the line 3-3 in FIG. 2. For convenience of explanation, the container body 20 is also shown, and the sheet lid 10 is enlarged in the thickness direction.
[0016]
The sheet lid 10 has a four-layer structure, and a paper layer 101, a polyethylene layer 102, an aluminum layer 103, and a strong heat seal layer 104 are laminated in this order from the upper side in FIG. The layer 105 is also a heat seal layer, but the heat seal layer 105 is a weak heat seal layer having a lower adhesive strength than the strong heat seal layer 104, as will be described later. The layers 101 to 104 are formed over the entire surface of the sheet lid, but the weak heat seal layer 105 is formed only on the portion corresponding to half of the ring-shaped flange 21 as shown by the hatched area in FIG. Forming.
[0017]
The strong heat seal layer 104 is formed of an EMAA (ethylene-methacrylic acid copolymer) -based thermal adhesive resin layer, while the weak heat seal layer 105 is an EVA (ethylene-vinyl acetate copolymer) -based. The heat-adhesive resin layer is formed. As described above, the heat bonding portion on the back surface of the sheet lid that contacts the flange portion 21 of the container main body is divided into two regions: a portion constituted by the strong heat seal layer 104 and a portion constituted by the weak heat seal layer 105. It will be divided.
[0018]
As a measure for comparing the adhesive strength of the heat seal layer, for example, in JIS, a 15 mm wide strip-shaped sample is taken for the heat seal layer, and the sample is compared with the maximum load necessary to peel it off at a speed of 300 mm / min. It is prescribed. When compared by this method, it is preferable that the strong heat seal layer 104 has an adhesive force of 1000 to 2500 g and the weak heat seal layer 105 has an adhesive force of 500 to 700 g. Thus, in the present invention, two types of heat seal layers having relatively different adhesive strengths are provided, and the weak heat seal layer 104 having a weak adhesive strength is provided in the vicinity of the opening tab 11.
[0019]
Adopting such a configuration has the following advantages. That is, when the sheet lid 10 is slightly peeled off for pouring hot water first, the tensile force required becomes small, and the operation becomes easy. Moreover, since the resistance to tension of the sheet lid 10 increases when the opening necessary for pouring hot water is formed, it is unlikely that the sheet lid 10 will be inadvertently pulled and unexpectedly peeled off. . Furthermore, since the difference in adhesive force between the two heat seal layers is achieved by the difference in the sealant component of the heat seal layer, the sealing process by the seal bar is not performed separately for each heat seal layer, There is a merit that it can be performed collectively.
[0020]
In the example of FIG. 2, the weak heat seal layer 105 is provided in an area corresponding to exactly half of the ring-shaped flange 21, but as can be seen from the above description, the weak heat seal layer 105 is used for pouring hot water. It suffices if the opening has a sufficient area to form an opening having a size that does not hinder the operation. For example, it is considered that there is no problem even if the expansion is about 1/3 of the entire ring-shaped flange 21. However, it is necessary to dispose it in the vicinity of the opening tab 11 that is picked when the sheet lid 10 is peeled off. This is to reduce the tensile force required first when starting to peel off.
[0021]
FIG. 4 is a modification of FIG. 3 in which the sheet lid 30 has a five-layer structure. From the upper side to the third layer in FIG. 4, the configuration is the same as that of FIG. 3, and includes a paper layer 301, a polyethylene layer 302, and an aluminum layer 303. A strong heat seal layer 305 is laminated on the lower side with a polyethylene layer 304 interposed therebetween. The weak heat seal layer 306 is formed in a region just half of the ring-shaped flange 21 as in the case of FIG.
[0022]
In the example of FIG. 4, EVA-based heat-adhesive resin is employed in both the strong heat-seal layer 305 and the weak heat-seal layer 306. It makes a difference in power. Specifically, the strong heat seal layer 305 has a low flowability with a melt flow rate (MFR) of about 5 to 50 (g / 10 min), and the weak heat seal layer 306 has an MFR of 30 to 200 (g / 10 minutes). The MFR is a measure indicating the fluidity when a thermoplastic resin is melted, and is defined by JIS. The weight extruded from the orifice in 10 minutes under a predetermined temperature and pressure condition is displayed in grams.
[0023]
FIG. 5 shows various variations of the formation region of the weak heat seal layer. In each of FIGS. 5A to 5C, the shaded area indicates the area where the weak heat seal layer is provided (the strong heat seal layer exists in the other areas). What is common to both examples is that a weak heat seal layer is provided in a predetermined range in the vicinity of the opening tab 11, and the weak heat seal layer is once interrupted. The effect of this is as described above. In the example of FIG. 5 (a), after the weak heat seal layer is interrupted, all the remaining areas are made strong heat seal layers. However, in the example of FIGS. 5 (b) and 5 (c), the weak heat seal layer is weak. After the layer is temporarily interrupted, a weak heat seal layer is formed again through a strong heat seal layer of a predetermined area.
[0024]
As described above, when the sheet lid is peeled off to form an opening for pouring hot water first, the tensile resistance of the sheet lid increases at the position where the strong heat seal layer is present. Therefore, if it can be achieved, it is advantageous that the adhesive strength of the remaining adhesive portion is weak when the entire sheet lid is finally peeled off. In that sense, the examples of FIGS. 5 (b) and (c) are considered advantageous.
[0025]
On the other hand, when the configuration of FIG. 5A is adopted, there is an advantage that when the weak heat seal layer is formed, it is not necessary to strictly align the formation position of the circular sheet lid and the weak heat seal layer. . That is, the sheet lid is formed by punching out a single sheet-like base material formed by laminating the above-mentioned layers, but if it is a weak heat seal layer having the shape shown in FIG. It is only necessary to form a weak heat-sealing layer extending in a strip shape on the sheet-like substrate and punch the sheet-like substrate so that each sheet lid partially includes the weak heat-sealing layer.
[0026]
As already described, the other layers including the strong heat seal layer are formed over the entire surface of the seal lid, and only the weak heat seal layer is partially provided only in the hatched region. However, it is of course possible to form the strong heat seal layer only on the portion corresponding to the flange portion 21 of the container body.
[0027]
In the example shown in FIGS. 3 and 4, the container body 20 made of expanded polystyrene is used. However, when the container body is made of paper, the components of the heat seal layer are also changed. This is because the adhesive strength of the heat seal layer varies depending on the material of the other party. For a paper container body, for example, if a five-layer structure as shown in FIG. 4 is considered, the upper four layers are the same as described above, but are actually bonded to the paper container body. The components of the “lowermost strong heat seal layer” and the “partially provided weak heat seal layer” are changed. Specifically, a polyethylene film (a blend of polypropylene and polyethylene or a blend of polyethylene and polybutylene) is used as a strong heat seal layer, and an EMAA or EVA heat adhesive resin layer is used as a weak heat seal layer. use.
[0028]
In the embodiment described above, the sheet lid functions only as a lid. However, for example, in instant foods such as cup fried noodles, a hot water cut end is provided in a part of the sheet lid. In such a seat lid, the configuration of the present invention is particularly beneficial. This is because, in the case of a seat lid with a hot water cut, the hot water cut works effectively by tilting the container only when a part of the sheet lid is fixed to the container body, and the seat lid is completely This is because if it comes off from the container body, it can no longer function as a hot water cut. In the present invention, the configuration of the hot water cut itself is not particularly limited, but an example thereof will be described below with reference to FIGS. 6 and 7. The configuration of the hot water cut itself described below is the same as that disclosed in another patent application filed by the applicant (Japanese Patent Application No. 11-6352).
[0029]
FIG. 6 is a plan view showing the back surface of the sheet lid, and corresponds to FIG. FIG. 7 is a cross-sectional view taken along line 7-7 in FIG. 6. Here, for convenience of explanation, the container body 20 is also shown. The sheet lid 10 ′ has a four-layer structure as in the case of FIG. 3, and the paper layer 101, the polyethylene layer 102, the aluminum layer 103, and the strong heat seal layer 104 are laminated in this order from the top. In this embodiment, the paper layer 101 constitutes the upper lid layer 111 according to claim 3, and the other three layers 102 to 104 constitute the lower lid layer 112.
[0030]
The sheet lid 10 ′ is obtained by adding a hot-cut opening tab 110 to the sheet lid 10 shown in FIGS. FIG. 7A shows a state before the tab 110 is peeled off, and FIG. 7B shows a state after the tab 110 is peeled off. I can understand. The hot water cut opening exposure tab 110 includes an upper tab layer 111a and a lower tab layer 112a. The lower tab layer 112a is obtained by dividing a part of the edge of the lower lid layer 112 by a cut 122. The upper tab layer 111a located on the upper side of the lower tab layer 112a extends in an area larger than the lower tab layer 112a toward the inside of the sheet lid 10 ′ and extends from the upper lid layer 111 by a cut 121. It is partitioned. Accordingly, a part of the lower lid layer 112 is covered with the upper tab layer 111a, and a circular cut 123 for forming a hot water cut end is formed in that part. Each cut 121, 122, 123 may be completely cut or broken.
[0031]
The hot cut forming cut 123 is indicated by three circles indicated by broken lines in FIG. By tearing off the hot water cut exposure tab 110, the cut 123 is broken and the hot water cut 108 is exposed there. Therefore, it is convenient that the boundary surface 115 between the upper tab layer 111a and the lower lid layer 112 is easily peeled except for the circular cut 123. Therefore, it is desirable to provide a release layer (not shown) for that portion. The hot water cut 108 is sealed until the hot water cut exposure tab 110 is peeled off, so that it is possible to effectively prevent the heat from escaping outside while pouring hot water and waiting for the smell to leak out. There is no issue.
[0032]
In the example of FIG. 7, a cut 123 for forming a hot water cut is provided, and the cut 123 is broken by peeling off the tab 110, whereby a hot water cut 108 is formed. It is also possible to adopt a configuration in which an opening (hot water cutout) is formed in the lid layer 112 and this is covered with the upper tab layer 111a of the hot water cutout exposure tab 110. In addition, as shown in FIG. 6, the hot water cut opening is provided on the opposite side to the opening tab 11 ′, that is, provided at the position opposite to the opening formed for pouring hot water first. desirable.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a cup noodle container according to an embodiment of the present invention.
FIG. 2 is a plan view showing the back surface of the sheet lid shown in FIG.
3 is a cross-sectional view taken along line 3-3 in FIG. The cup container body is also shown.
4 shows a cup noodle container according to another embodiment of the present invention and is a cross-sectional view corresponding to FIG.
FIG. 5 is a plan view showing a variation of the formation position of the weak heat seal layer in the cup noodle of the present invention.
FIG. 6 is a plan view showing a back surface of a seat lid according to still another embodiment of the present invention.
7 is a cross-sectional view taken along line 7-7 in FIG. The cup container body is also shown.
[Explanation of symbols]
1 cup noodle container
10, 10 ', 30 seat lid
11 Opening tab
20 Container body
21 Flange
21a Inner edge of flange
101 paper layers
102 Polyethylene layer
103 Aluminum layer
104 Strong heat seal layer
105 Weak heat seal layer
108 Hot water outlet
110 Tab for exposure
111 Upper lid layer
111a Upper tab layer
112 Lower lid layer
112a Lower tab layer
115 Interface between upper tab layer and lower lid layer
121, 122, 123 cuts
301 Paper layer
302 Polyethylene layer
303 Aluminum layer
304 Polyethylene layer
305 Strong heat seal layer
306 Weak heat seal layer

Claims (5)

A multi-layered sheet lid that is provided with an opening tab (11) and is thermally bonded to the opening edge (21) of the container body,
Of the thermal bonding part that contacts the opening edge of the back surface of the sheet lid, at least the area in the vicinity of the opening tab (11) is composed of a weak heat seal layer (105, 306) with relatively weak adhesive force, Consists of parts other than the weak heat seal layer with a strong heat seal layer (104, 305) with relatively strong adhesive force,
The weak heat seal layer (105, 306) in the vicinity of the opening tab has such an area that an opening that does not hinder hot water pouring when the sheet lid portion corresponding to the layer is peeled off is formed. Forming,
Except for the weak heat seal layer (105, 306), other layers including the strong heat seal layer (104, 305) are formed over the entire surface of the seat lid, and only the weak heat seal layer (105, 306) is strong. A sheet lid characterized by being partially formed on the heat seal layer (104, 305).   The difference in adhesive force between the strong heat seal layer (104, 305) and the weak heat seal layer (105, 306) is caused by a difference in the sealing agent component constituting each layer, The sheet lid according to 1. The opening tab is a straight boundary line across the entire sheet lid. (11) Is divided into a first region and a second region,
  The above weak heat seal layer (105 , 306) The sheet lid according to claim 1, wherein the sheet lid is formed on the entire surface of the first region. The sheet lid according to any one of claims 1 to 3, wherein the sheet lid is configured by laminating an upper lid layer (111) and a lower lid layer (112), and further includes a hot-cut exposure tab (110). And
The hot cut opening exposure tab (110) includes a lower tab layer (112a) in which a part of an edge of the lower lid layer (112) is partitioned by a notch (122), and the lower tab layer toward the inside of the sheet lid. An upper tab layer (111a) that is partitioned from the upper lid layer (111) by a notch (121) with a portion extending wider than the layer,
The sheet lid is characterized in that when the hot-cut exposure tab (110) is peeled off, the hot-cut (108) is exposed to the lower lid layer covered with the upper tab layer.   A container with a sheet lid, wherein the sheet lid according to claim 1, 2, 3 or 4 is thermally bonded to an opening edge of the container body.

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