JP2016108039A - Heat insulation paper container - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a heat insulation paper container capable of suppressing formation of a salient-state step on a foam heat insulation layer on a trunk inner peripheral side on a side seam part, with a simple structure.SOLUTION: A heat insulation paper container comprises: a trunk 40 which is obtained by rolling up a blank material having a paper base material layer 20 and a thermoplastic resin layer 30, in which the thermoplastic resin layer 30 is an inner peripheral side; and a bottom part, in which moisture in the paper base material layer 20 is heated and evaporated for foaming the thermoplastic resin layer 30. The trunk 40 has a side seam part 45 formed by laminating a first side end part 41 and a second side end part 44 of the blank material in which the first side end part 41 is an inner peripheral side, and adhering them. The first side end part 41 has an inclination end edge 43a which extends in a plane of the trunk 40, so as to form an angle to an orthogonal direction X orthogonal to an outer peripheral edge of the bottom part, on at least a part from the bottom part to an intermediate area on an upper end of the trunk 40.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a heat insulating paper container comprising a body made of a blank material having a paper base material layer and a thermoplastic resin layer, and foaming the thermoplastic resin layer by heating and evaporating water in the paper base material layer. About.

  2. Description of the Related Art Conventionally, a paper container in which a fan-shaped base paper is formed into an inverted frustoconical cup shape and a bottom opening is closed by a bottom plate has been widely used. Such a paper container has the advantage that it can be easily incinerated because it uses paper as the main material, and does not generate harmful gases during the incineration process, but the barrel is made of paper. Since it is comprised, when hot drink etc. are put, if it has a trunk | drum with a hand, it has the subject that heat will be transmitted easily to a hand.

  Then, as one means for solving the problem that heat is easily transmitted to the hand described above, a heat insulating paper container having a foam heat insulating layer provided on the outer peripheral side of the body has been proposed (for example, see Patent Document 1). This type of heat-insulating paper container is made by foaming the thermoplastic resin layer by releasing moisture in the paper base material layer to the thermoplastic resin layer such as expanded polystyrene provided on the outer peripheral side of the trunk, A foam insulation layer is formed on the side. This makes it possible to impart heat resistance to the container, and brings about the advantage that it can be easily held even when hot contents are filled.

  However, such a heat insulating paper container having a foam heat insulating layer formed on the outer peripheral side of the trunk portion is excellent in heat insulation, but the smoothness of the outer peripheral surface of the trunk portion is lowered. There arises a problem that it is difficult to print raw materials or barcodes. For this reason, in consideration of the printability of the outer peripheral surface of the body described above, a container having a foam heat insulating layer provided on the inner peripheral side of the body instead of the outer periphery of the body has been proposed (see, for example, Patent Document 2).

  As described above, when the foam heat insulating layer is formed on the inner peripheral side of the trunk part, not only can the printability of the outer peripheral surface of the trunk part be improved, but also by covering the inner peripheral side of the trunk part with the foam heat insulating layer, The penetration can be prevented, and the adhesion and fitting property between the lid seal bonded to the mouth part at the upper end of the trunk part and the mouth part can be improved.

JP-A-9-95368 JP 2003-237855 A

  However, when the foam heat insulation layer 130 is formed on the inner peripheral side of the trunk portion as in the case of the container 110 described in Patent Document 2, the side seam portion 145 of the trunk portion 140 protrudes from the foam heat insulation layer 130 as shown in FIG. Another problem arises that the stepped P is formed.

  That is, in the body part 140 of such a container 110, as shown in FIG. 6, a side seam part 145 is formed by overlapping and bonding the first side end part 141 and the second side end part 144 of the blank material. In the side seam portion 145 where the first side end portion 141 and the second side end portion 144 overlap, the thermoplastic resin layer 130 and the second side of the first side end portion 141 by the water vapor released from the paper base material layer 120. The thermoplastic resin layer 130 at the end portion 144 is foamed, and as a result, a convex step P is formed in the foam heat insulating layer 130.

  And, by forming the convex step P on the foam heat insulating layer 130 on the inner peripheral side of the body in this way, chopsticks or the like are caught on the convex step P of the foam heat insulating layer 130 when the container is used, and the foam heat insulating layer There has been a problem in using the container, such as partial stagnation in 130 or a deterioration in stackability of the container 110.

  Therefore, the present invention solves these problems, and with a simple configuration, a heat insulating paper container that suppresses the formation of a convex step in the foam heat insulating layer on the inner peripheral side of the body portion in the side seam portion. Is intended to provide.

  The present invention includes a body portion obtained by rolling a blank material having a paper base material layer and a thermoplastic resin layer into a cylindrical shape with the thermoplastic resin layer as an inner peripheral side, and a bottom portion. A heat insulating paper container formed by foaming the thermoplastic resin layer by heating and evaporating water of the body, wherein the body portion has the first side end and the second side end of the blank material on the first side. A side seam portion is attached with the end portion being an inner peripheral side, and the first side end portion has an angle with respect to an orthogonal direction orthogonal to the outer peripheral edge of the bottom portion within the surface of the body portion. The above-mentioned problem is solved by having an inclined edge extending so as to be formed in at least a part of an intermediate region from the bottom to the upper end of the trunk.

According to the first aspect of the present invention, the blank material having the paper base material layer and the thermoplastic resin layer is provided with a barrel portion that is rounded into a cylindrical shape with the thermoplastic resin layer as an inner peripheral side, and a bottom portion. A heat-insulating paper container formed by foaming a thermoplastic resin layer by heating and evaporating moisture in a paper base material layer, wherein the body portion includes the first side end and the second side end of the blank material as the first end. It has a side seam part that is attached with the side end part set to the inner peripheral side, and the first side end part forms an angle with respect to the orthogonal direction perpendicular to the outer peripheral edge of the bottom part in the surface of the body part. And at least a portion of the middle region from the bottom to the top of the barrel.
Thereby, the total area of the edge of the paper base material layer at the first side edge is increased by providing the inclined edge, and when the moisture of the paper base material layer is heated and evaporated, Excess water vapor can escape from the edge, so the foaming state of the thermoplastic resin layer at the side seam can be controlled, and a convex step is formed in the foam insulation layer on the inner periphery of the body with a simple structure Can be prevented.

According to the second aspect of the present invention, a plurality of concave portions that are recessed in the circumferential direction of the body portion are formed in the first side end portion in the vertical direction, so that the edge forming position of the first side end portion is formed. Since it is possible to form a large number of inclined edges while keeping the inner surface within a certain range in the circumferential direction of the body portion, it is easy to crimp the first side end portion and the second side end portion when forming the side seam portion. It is possible to ensure a large total area of the edge of the paper base material layer at the first side end while securing the property.
According to the third aspect of the present invention, the plurality of recesses are formed in the reference end edge of the first side end portion extending along the orthogonal direction, so that the formation position of the end edge of the first side end portion is the body portion. Since it is possible to fit within a narrow range in the circumferential direction, it is possible to ensure the ease of pressure bonding of the first side end and the second side end.
According to the fourth aspect of the present invention, since the inclined edge is formed so as to form an angle of 90 ° with respect to the orthogonal direction, the total edge of the paper base material layer at the first side edge is formed. A larger area can be secured.

Sectional drawing which shows the heat insulation paper container which concerns on one Embodiment of this invention. The whole heat insulating paper container sectional drawing concerning Example 1, and the cross-sectional enlarged view of an AA cross-section part. The whole sectional view of the heat insulation paper container concerning Example 2, and the section enlarged view of a BB section. The whole sectional view of the heat insulation paper container concerning Example 3, and the section enlarged view of CC section. Sectional drawing which shows the modification of an insulated paper container. The whole sectional view of the conventional heat insulation paper container, and the section enlarged drawing of DD section.

  Below, the heat insulation paper container 10 which concerns on one Embodiment of this invention is demonstrated based on drawing.

  As shown in FIG. 1, the heat insulating paper container 10 has a blank material having at least a paper base layer 20 and a thermoplastic resin layer 30 such as polyethylene in an inverted frustoconical shape with the thermoplastic resin layer 30 as an inner peripheral side. It comprises a rolled body 40 and a bottom 50 made of a paper material formed in the vicinity of the lower end of the body 40, and foams the thermoplastic resin layer 30 by heating and evaporating moisture in the paper base material layer 20, The foam heat insulating layer 30 is formed on the inner peripheral side of the body portion 40. A non-foamed polyethylene layer is formed on the inner peripheral side of the thermoplastic resin layer (foamed heat insulating layer) 30, and a thermoplastic resin layer such as polyethylene or PET is formed on the outer peripheral side of the paper base material layer 20. Although formed, these layers are not shown.

  As shown in FIG. 1, the body portion 40 includes a side seam portion 45 in which the first side end portion 41 and the second side end portion 44 of the blank material are overlapped and bonded with the first side end portion 41 as the inner peripheral side. Have. The side seam portion 45 is formed by applying an adhesive between the first side end portion 41 and the second side end portion 44, or after heating and melting the thermoplastic resin on the joining surface, respectively. 41 and the second side end 44 are formed by pressure bonding.

  As shown in FIG. 1, the first side end 41 of the body 40 has a recess 43 that is recessed from the reference edge 42, which is an edge in the body circumferential direction, toward the body circumferential direction. In the middle region at the upper end of the portion 40, a plurality are formed at intervals in the orthogonal direction (vertical direction) X. The reference edge 42 extends along the orthogonal direction X orthogonal to the outer peripheral edge of the bottom 50 in the plane of the body 40. Further, the upper and lower end edges of the recess 43 function as inclined end edges 43 a extending so as to form an angle of 90 ° with respect to the orthogonal direction X. In the present embodiment, the bottom edge of the recess 43 extends along the orthogonal direction X.

  Next, the performance test performed in order to confirm the foaming suppression effect of the heat insulating paper container 10 is demonstrated below based on FIGS.

  First, the test conditions for the performance test are as follows.

[Body configuration]
The body 40 is formed from the inner peripheral surface side of the container, from non-foamed polyethylene (15 μm), foamed polyethylene (55 μm), base paper 300 g / m ² , high-melting polyethylene (12 μm), PET film (12 μm), high-melting polyethylene (12 μm). Formed with.
[Foaming conditions]
The heat-insulated paper container 10 before heating and foaming is stored for 24 hours in an environment of 23 ° C. and a relative humidity of 50%, humidity is adjusted, and the moisture content condition in the base paper is adjusted to 7 wt%, and then the foamed oven is 116 ° C. For 240 seconds.
[Cross-section observation method]
After cutting the heat insulating paper container 10 at a position of 75 mm in the orthogonal direction (vertical direction) X from the bottom 50 (AA line position, BB line position, CC line position), the cross section is viewed with a microscope. Observed.

  Next, the configuration and observation results of each example are as follows.

[Example 1]
First, in Example 1, as shown in FIG. 2, a plurality of recesses 43 were formed in the first side end portion 41 of the body portion 40 at intervals in the orthogonal direction X. Moreover, the dimension of the inclined edge 43a (upper and lower end edges of the recessed part 43) was set to 1 mm, the dimension of the bottom edge of each recessed part 43 was set to 5 mm, and each inclined edge 43a was formed at intervals of 5 mm.
In Example 1, as shown in FIG. 2, it was confirmed that no convex step P was formed in the foamed thermoplastic resin layer (foamed heat insulating layer) 30 in the AA cross section.
[Example 2]
Next, in Example 2, as shown in FIG. 3, one concave portion 43 was formed in the first side end portion 41 of the body portion 40. Further, the dimension of the inclined edge 43a (upper and lower edges of the recess 43) was set to 1 mm, and the dimension of the bottom edge of the recess 43 was set to 5 mm.
In Example 2, as shown in FIG. 3, it was confirmed that a convex step P was not formed in the foamed thermoplastic resin layer (foamed heat insulating layer) 30 in the BB cross section.
[Example 3]
Next, in Example 3, as shown in FIG. 4, one concave portion 43 was formed in the first side end portion 41 of the body portion 40. Further, the dimension of the inclined edge 43a (upper and lower edges of the recess 43) was set to 0.5 mm, and the dimension of the bottom edge of the recess 43 was set to 5 mm.
In Example 3, as shown in FIG. 4, it was confirmed that a convex step P was formed in the foamed thermoplastic resin layer (foamed heat insulating layer) 30 in the CC cross section.

From the comparison between Example 2 and Example 3 described above, in order to obtain the foam suppression effect in the region of 25 mm in the orthogonal direction X, it is necessary to form a total of 2 mm or more of the inclined edge 43a, in other words, the inclined end. It has been found that the total extension distance of the edge of the first side end portion 41 needs to be increased by 8% (2 mm / 25 mm) by forming the edge 43a.
Explaining the above in detail, as shown in FIG. 3 and FIG. 4, 10 mm in the orthogonal direction X where the foaming suppression effect by the inclined end edge 43a has an effect is added to the dimension of the bottom edge of the recess 43 as shown in FIG. In the 25 mm (10 mm + 5 mm + 10 mm) region of the orthogonal direction X, when the inclined edge 43a of 2 mm (1 mm + 1 mm) in total is formed as in Example 2, a foaming suppression effect is obtained in the 25 mm region of the orthogonal direction X. However, in contrast to this, when the inclined edge 43a having a total of 1 mm (0.5 mm + 0.5 mm) was formed as in Example 3, the foam suppression effect was not obtained.

Moreover, in Example 2, when the presence or absence of the formation of the convex level | step difference P in the side seam part 45 was confirmed, if the distance from the inclination edge 43a is the range within 10 mm in the orthogonal direction X, a convex level | step difference will be carried out. P was not formed. From this, it was found that if the distance from the inclined end edge 43a is within 10 mm, the foaming suppression effect can be obtained.
Then, as shown in the first embodiment, by forming a plurality of inclined end edges 43a continuously in the orthogonal direction X (in the case of the first embodiment, continuously with a predetermined interval), the inclined end edges 43a are formed. It was found that the foam suppression effect can be obtained over the entire formed region.

  As mentioned above, although embodiment of this invention was explained in full detail, this invention is not limited to the said embodiment, A various design change can be performed without deviating from this invention described in the claim. Is possible.

For example, in the above-described embodiment, the upper and lower end edges of the plurality of recesses formed in the first side end portion have been described as functioning as the inclined end edge, but the specific aspect of the inclined end edge is the outside of the bottom portion. As long as it extends so as to form an angle with respect to the orthogonal direction orthogonal to the peripheral edge, for example, as shown in FIG. 5, the edge of the first side end portion 41 is formed in a zigzag shape, The straight line portion 43a may function as the inclined edge 43a, and the inclined edge may be formed in a curved shape.
Further, in the above-described embodiment, the configuration of the body portion is configured from the non-foamed polyethylene layer, the thermoplastic resin layer, the paper base material layer, the high melting point polyethylene layer, the PET film layer, and the high melting point polyethylene layer from the inner peripheral side. However, the specific configuration of the body portion is not particularly limited as long as it includes a paper base layer and a thermoplastic resin layer, and a thermoplastic resin layer is disposed on the inner peripheral side of the paper base layer. But you can.

DESCRIPTION OF SYMBOLS 10 ... Heat insulation paper container 20 ... Paper base material layer 30 ... Thermoplastic resin layer (foaming heat insulation layer)
40 ... Body 41 ... First side end 42 ... Reference edge 43 ... Recess 43a ... Inclined edge 44 ... Second side end 45 ... Side seam part 50 ... Bottom X ... Orthogonal direction P ... Convex step

Claims (4)

A blank material having a paper base material layer and a thermoplastic resin layer is provided with a body portion that is rolled into a cylindrical shape with the thermoplastic resin layer as an inner peripheral side, and a bottom portion, and heats moisture in the paper base material layer. A heat insulating paper container formed by foaming the thermoplastic resin layer by evaporating;
The body portion includes a side seam portion that is attached by overlapping the first side end portion and the second side end portion of the blank material with the first side end portion being an inner peripheral side,
The first side end portion has an inclined edge extending so as to form an angle with respect to an orthogonal direction orthogonal to the outer peripheral edge of the bottom portion within the surface of the body portion, and is intermediate between the bottom portion and the upper end of the body portion. An insulated paper container having at least a part of the region.   2. The heat insulating paper container according to claim 1, wherein a plurality of concave portions recessed in the circumferential direction of the body portion are formed in the first side end portion in the vertical direction. The first side end portion has a reference edge extending along the orthogonal direction,
The recess is formed so as to be recessed from the reference edge toward the body circumferential direction,
The heat insulating paper container according to claim 2, wherein the plurality of concave portions are formed at intervals in the vertical direction.   The insulated paper container according to any one of claims 1 to 3, wherein the inclined edge is formed so as to form an angle of 90 ° with respect to the orthogonal direction.