JP2000190948A - Paper container, and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To reduce the ratio of use of plastics by assembling a paper container body comprising a main blank comprising a frame-like flange and a pair of side surfaces continuously provided on the inner side of the flange, and a sub blank comprising a bottom surface and a pair of the other side surfaces, and providing an external protective film layer on its inner surface. SOLUTION: A main blank 10 comprising a rectangular flange 3 mainly formed of paper and a pair of side surfaces 4, 4 opposite to each other which are continuously provided on the inner side of the flange 3 through a folding line, and a sub blank 11 comprising a bottom surface 5 formed mainly of paper and a pair of the other side surfaces 6, 6 which are continuously provided on the main blank 10 and form other side surfaces than the side surfaces 4, 4, are prepared. A paper container body 1 is assembled using the main and sub blanks 10, 11, and an internal protective film layer is provided to complete a container by closely attaching the bottom surface 5, the side surfaces 4, 6 and the flanges 3 by a thermoplastic resin film consisting of a thermoplastic resin.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper container and a method of manufacturing the same, and more particularly, to a paper container sealable with a sealing lid and a method of manufacturing the same.

[0002]

2. Description of the Related Art Conventionally, tray-shaped containers have been
Various things such as paper or plastic have been put to practical use, but when the contents contain liquids or when sufficient sealing properties are required, it is composed of paper alone. A paper container or a container assembled with paper whose inner surface has been subjected to resin processing cannot be used because it does not have sufficient sealing properties. In order to have sufficient sealing properties, it is necessary to provide an appropriate flange portion for hermetically sealing with a sealing lid, and from these viewpoints, a plastic molded tray sealed with a sealing lid Plastic containers are common. Further, instead of using paper or plastic as a single material, containers using a composite material of paper and plastic are disclosed in Japanese Patent Application Laid-Open Nos.
No. 253237.

[0003]

However, in the above plastic container, after use as a container,
There is a problem with their disposal, and now these used containers can be collected and reused or burned,
Alternatively, it has been treated such as discarded as it is,
In any case, the state is not sufficiently satisfactory, and a reduction in the amount of use is required. Further, the design of the surface of the container is also inferior to the paper container in terms of printing effect and difficulty in printing.

Further, a container using a material composed of a composite of paper and plastic, for example, Japanese Patent Application Laid-Open No. Hei 3-12003
No. 4, JP-A-8-253237, etc., the flanges also have overlapping portions or seams, and are not smooth and integral with no steps. There is a problem that a proper sealing cannot be performed. Further, there is a problem that it is not easy to assemble the container blank in the mold, and the assembled shape is easily deformed.

The present invention has been made in view of such a background, and an object of the present invention is to provide a container which is made of paper as a main material and has a material composition with a small ratio of plastic and which is compatible with environmental problems. Yes, and it is easy to assemble the container blank in the molding die, the assembled shape is difficult to deform, and the flange is a smooth integral body without overlapping parts or seams,
An object of the present invention is to provide a container that can be sufficiently sealed by a sealing lid.

[0006]

The above object can be attained by the following invention.

According to a first aspect of the present invention, there is provided a main blank comprising a frame-shaped flange made of paper as a main material, and a pair of opposed side surfaces continuously connected to the inside of the flange via a broken line; Internal protection comprising a paper container body assembled with a sub blank consisting of a side surface other than the side surface connected to the main blank, and a thermoplastic resin film tightly adhered to the inner surface of the paper container body. A paper container comprising a film layer.

According to the present invention, it is easy to assemble the two blanks, the main blank and the sub-blank, constituting the paper container body of the paper container in the molding die, the assembled shape is hardly deformed, and Since the flange is a smooth integral body having no overlapping portions or seams, sufficient sealing with a seal lid is possible, and the main material is paper, and the material is composed of a material having a small ratio of plastic. A paper container corresponding to environmental problems can be obtained.

According to a second aspect of the present invention, in the paper container according to the first aspect, the frame-shaped flange of the main blank has a polygonal shape, and the bottom surface of the sub-blank has a polygonal shape. It is characterized by the following.

According to this invention, in addition to the effects of the invention described in the first aspect, the flange of the main blank and the bottom surface of the sub-blank are formed in a polygonal shape, so that the shape becomes stable and the appearance is improved. A good paper container can also be obtained.

[0011] The invention described in claim 3 is the invention according to claim 1 or 2.
Wherein the sub-blank comprises the bottom surface and the side surfaces other than the side surfaces connected to the main blank connected to the bottom surface via a broken line. is there.

According to this invention, in addition to the effect of the invention described in the first or second aspect, the side surface connected to the bottom surface of the sub blank can be easily bent to form the paper container body.

The invention described in claim 4 is the first or second invention.
In the paper container according to the above, the sub-blank is composed of the bottom surface, and a pair of opposing side surfaces other than the side surface connected to the main blank connected to the bottom surface via a broken line, The present invention is characterized in that side surfaces are further provided continuously on both sides via broken lines.

According to this invention, in addition to the effect of the invention described in the first or second aspect, the side surface connected to the bottom surface of the sub-blank can be easily bent to form the paper container body. In addition, the paper can be conveniently used for blank production, and the material can be used economically.

According to a fifth aspect of the present invention, in the paper container according to the second aspect, the main blank has a square shape of the flange, and a pair of opposed sides inside the flange with a broken line. The sub-blank has a shape of the bottom surface being octagonal, and a pair of opposing squares other than the side surfaces connected to the main blank via a polygonal line on the bottom surface. And two pairs of opposing triangular side surfaces are connected to each other.

According to this invention, in addition to the effect of the invention described in the second aspect, by forming the bottom surface into an octagonal shape, a paper container with less deformation and good shape retention can be obtained. There is an advantage that it is easy to take things out.

According to a sixth aspect of the present invention, in the paper container according to the second aspect, the main blank has a square shape of the flange, and a pair of opposed sides inside the flange with a broken line. The sub-blank has a shape of the bottom surface being octagonal, and a pair of opposing squares other than the side surfaces connected to the main blank via a polygonal line on the bottom surface. And a triangular side surface which is continuously provided on both sides of the side surface via a polygonal line.

According to this invention, in addition to the effect of the invention described in the second aspect, by forming the bottom surface into an octagonal shape, a paper container having good shape retention with little deformation is provided. There is an advantage that it is easy to take things out.
In addition, the paper can be conveniently used for blank production, and the material can be used economically.

According to a seventh aspect of the present invention, in the paper container according to the first aspect, the main blank is such that the shape of the flange is a square with rounded corners, and the main blank has a straight side inside the flange. A pair of opposing side surfaces are continuously provided via a broken line, and the sub-blank has a shape of the bottom surface with a rounded rectangle, and is connected to the main blank on a straight side of the bottom surface. A pair of opposed side surfaces other than the side surfaces,
The invention is characterized in that both sides of the side face are connected to the side face via broken lines.

According to this invention, in addition to the effects of the invention described in the first or second aspect, the four corners of the rectangular paper container are assembled with rounded corners, so that the whole is rounded. It is possible to obtain a paper container having a good appearance in shape.

[0021] The invention described in claim 8 is the invention according to claims 1 to 7.
In the paper container according to any one of the above, on the inner side of the flange of the main blank, a reinforcing piece is provided on a side other than the side where the pair of opposed side surfaces are continuously connected via a broken line. It is characterized by the following.

According to this invention, in addition to the effects of the inventions described in the first to seventh aspects, by providing a portion where the main blank and the sub-blank are adjacent to each other with a reinforcing piece at an adjacent portion, the paper container is made of paper. This has the effect of maintaining the shape and increasing the strength.

According to a ninth aspect of the present invention, there is provided a main blank comprising a frame-shaped flange made of paper as a main material and a pair of opposing side surfaces continuously connected to the inside of the flange via a broken line; The sub blank consisting of the side other than the side connected to the main blank is put in a mold for vacuum or pressure forming, and a paper container body which is a semi-finished product is assembled in the mold and is in a heated state. A method for producing a paper container, characterized in that a film made of a thermoplastic resin is formed by vacuum or compressed air, or a combination thereof, and tightly adhered to the entire inner surface of a paper container main body to form an inner protective film layer.

According to the present invention, it is easy to assemble the two blanks, the main blank and the sub-blank, which constitute the paper container body of the paper container in the molding die, the assembled shape is hardly deformed, and the assembled shape is extremely difficult. Since the container can be manufactured in a simple process, and the flange is a smooth integral body without any overlapped portions or seams, it is possible to obtain a paper container having a sufficient sealing property with a seal lid. .

That is, according to the present invention, paper is used as a main material.
A main blank consisting of a frame-shaped flange and a pair of opposing side surfaces connected to each other through a broken line inside the flange, and a sub blank consisting of a bottom surface and side surfaces other than the side surfaces connected to the main blank. An assembled paper container body,
A paper container characterized by comprising an inner protective film layer made of a thermoplastic resin film which is suctioned to the inner surface of the paper container main body in a heated state by vacuum or compressed air and closely adhered thereto.

Further, according to the present invention, there is provided a main blank made of paper as a main material, comprising a frame-shaped flange and a side face continuously connected to the inside of the flange through a broken line, and a bottom face and the main blank connected to the main blank. A sub blank consisting of a side surface other than the side surface is placed in a molding die for vacuum or air pressure molding, a paper container body as a semi-finished product is assembled in the molding die, and the thermoplastic resin film in a heated state is evacuated. Or a method for producing a paper container, wherein the inner protective film layer is formed by molding by pressurized air or a combination thereof and tightly adhering the entire inner surface of the paper container body.

[0027]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the paper container of the present invention, such as the shape, materials used, and manufacturing method, will be described with reference to the drawings. Identical or similar parts are given the same reference numerals.

FIG. 1 is a perspective view showing an example of a paper container according to the first embodiment of the present invention in which the flange of the main blank is rectangular and the bottom of the sub blank is also rectangular. The paper container A according to the present invention includes a flange 3, side surfaces 4, 4, 6,
The main body is a paper container main body 1 having a bottom surface 5 and a paper container main body 6, and further has an inner protective film layer 2 in which a thermoplastic resin film is closely adhered to the inner surface of the paper container main body 1. That is, the paper container A according to the present invention.
As shown in FIG. 2, a main blank 10 composed of a square flange 3 and a pair of opposed side surfaces 4 and 4 made of paper as a main material, a side surface 4 connected to the bottom surface 5 and the main blank 10, The paper container main body 1 is assembled with the sub blank 11 including the side surfaces 6 and 6 other than the side surface 4, and the bottom surface 5, the side surfaces 4, 4, 6 and 6, and the flange 3 are formed of a thermoplastic resin. The container is formed by providing the inner surface protection film layer 2 by tightly bonding with a plastic resin film.

FIG. 3 is an exploded view of the main blank 10 for assembling the paper container body 1, and FIG.
FIG. Since these blanks are mainly made of paperboard, they can be easily printed on the surface and have good printing effects.

In the main blank 10 shown in FIG. 3, a pair of opposing sides inside a rectangular flange 3 which is an integral part without an overlap portion or a seam is connected through a broken line a.
A pair of bendable opposing side surfaces 4, 4 are provided in series. The broken line a is preferably perforated or partially cut so that the side surfaces 4 and 4 are easily bent. The shape of the side surfaces 4 and 4 is quadrangular, and is mainly a trapezoid that expands upward, so that a tapered tray shape is obtained after assembly.

In the sub-blank 11 shown in FIG. 4, the side face other than the side face 4 connected to the main blank can be bent along the bottom face 5 and a pair of opposing sides outside the bottom face 5 via a broken line b. A pair of opposing side surfaces 6, 6 are continuously provided. As the side surface other than the side surface connected to the main blank, if the bottom surface is a square, it will be a pair of opposed side surfaces, but if it is a quadrangle or more polygon, other than the side surface connected to the main blank. The number of sides increases to more than one pair. The broken line b is preferably perforated or partially cut so that the side surfaces 6 and 6 are easily bent. The side surfaces 6 and 6 have a quadrangular shape, and like the side surfaces 4 and 4, have a trapezoidal shape that expands mainly upward, so that a tapered tray shape is obtained after assembly.

FIG. 5 is a perspective view showing an example in which the flange of the main blank is octagonal and the bottom surface of the sub blank is octagonal in the second embodiment of the paper container of the present invention. The paper container B according to the present invention comprises a main blank 20 made of paper as the main material and having an octagonal flange 3 and a pair of opposed side surfaces 4 and 4, and a bottom surface 5 and side surfaces 4 and 4 connected to the main blank 20. A pair of opposed side surfaces 6 and 6
And a sub blank 2 composed of two pairs of side surfaces 7, 7, 7, 7
1, the paper container body 1 is assembled, and its bottom surface 5, each side surface 4, 4, 6, 6, 7, 7, 7, 7 and flange 3
Is provided with an inner protective film layer 2 by tightly bonding with a thermoplastic resin film to constitute a container.

FIG. 6 is a developed view of a main blank 20 for assembling the paper container body 1 of the paper container B according to the present invention, FIG. 7 is a developed view of a sub blank 21, and FIG. It is a development view of the auxiliary blank 22 of FIG. Since these blanks are mainly made of paperboard, they can be easily printed on the surface and have good printing effects.

In the main blank 20 shown in FIG. 6, a pair of opposing side faces that can be bent through a fold line a are provided on a pair of opposing sides inside an octagonal flange 3 that is an integral part without an overlapping portion or a seam. 4 and 4 are connected in series. The broken line a is preferably perforated or partially cut so that the side surfaces 4 and 4 are easily bent. The shape of the side surfaces 4 and 4 is quadrangular, and is mainly a trapezoid that expands upward, so that a tapered tray shape is obtained after assembly.

In the sub-blank 21 shown in FIG. 7, a pair of side surfaces other than the side surfaces 4 and 4 connected to the main blank are provided on the bottom surface 5 and a pair of opposite sides of the bottom surface 5 via a broken line b. Opposing sides 6, 6 and two pairs of sides 7,
7, 7, 7 are connected in series. This broken line b is
Perforations or half cuts are preferred so that 6, 7, 7, 7, 7 can be easily bent. This side 6, 6, 7, 7,
The shape of 7, 7 is a quadrangle and, like the side surfaces 4 and 4, a trapezoid that expands mainly upwards, so that it becomes a tapered tray shape after assembly.

FIG. 8 shows, in the paper container B according to the present invention, a sub-blank 22 having a shape different from the above-mentioned sub-blank 21 as a sub-blank corresponding to the main blank 20. In the sub-blank 22, a pair of opposing side surfaces 6, which can be bent as the side surfaces other than the side surfaces 4, 4 connected to the main blank 20 via a broken line b on the bottom surface 5 and a pair of opposing sides of the bottom surface 5. , 6 and two pairs of side surfaces 7, 7, 7, 7 are continuously provided on both sides of the side surfaces 6, 6 via a polygonal line c. The polygonal lines b and c correspond to the side surfaces 6, 6, 7,
Perforations or half cuts are preferred so that 7, 7, 7 can be easily bent. The shape of the side surfaces 6, 6, 7, 7, 7, 7 is a quadrangle, and like the side surfaces 4 and 4, a trapezoidal shape which mainly expands upwards, thereby forming a tapered tray shape after assembly.

As described above, in the first embodiment and the second embodiment of the paper container of the present invention, when the shape of the flange 3 of the main blank and the shape of the bottom surface 5 of the sub blank are square, Although the case of the octagon is specifically described, the shape of the bottom surface 5 and the flange 3 may be any shape such as a pentagon, a hexagon, and a decagon as long as the shape is a triangle or more.

FIG. 9 is a perspective view showing a third embodiment of the paper container of the present invention in which the flange of the main blank is square and the bottom of the sub blank is octagonal. As shown in FIG. 10, the paper container C includes a main blank 30 made of paper as a main material and having a rectangular flange 3 and a pair of opposed side surfaces 4 and 4, a bottom surface 5 and a main blank 30. And a pair of opposing side surfaces 6 and 6 which are side surfaces other than the side surfaces 4 and 4 and two pairs of triangular side surfaces 7 and 7.
The paper container main body 1 is assembled with the sub blank 31 composed of 7, 7 and the two pairs of side surfaces 7, 7, 7, 7 are triangular. The inner surface protection film layer 2 is provided by closely bonding the bottom surface 5, the side surfaces 4, 4, 6, 6, 7, 7, 7, 7 and the flange 3 of the paper container main body 1 with a thermoplastic resin film. Constitutes a container.

The exploded view of the main blank 30 for assembling the paper container main body 1 of the paper container C according to the present invention is the same as the main blank 10 of the paper container A shown in FIG. FIG. 12 is a developed view of another sub-blank 32. Since these blanks are mainly made of paperboard, they can be easily printed on the surface and have good printing effects.

In the sub-blank 31 shown in FIG.
On a pair of opposite sides of the bottom surface 5 via a broken line b,
A pair of opposing side surfaces 6, 6, which can be bent as side surfaces other than the side surfaces 4, 4 connected to the main blank 30, and two pairs of side surfaces 7, 7, 7, 7 are provided in series. The shape of the side surfaces 6, 6 is a quadrangle, and like the side surfaces 4, 4, it is a trapezoid that mainly expands upward. However, the shapes of the two pairs of side surfaces 7, 7, 7, 7 are triangular. This polygonal line b has side surfaces 6, 6, 7, 7,
Perforations or half cuts are preferred so that 7, 7 can be easily bent.

FIG. 12 shows a sub-blank 32 having a shape different from that of the sub-blank 31 as a sub-blank corresponding to the main blank 30 in the paper container C according to the present invention.
Is shown. In the sub-blank 32, a pair of opposing side surfaces that can be bent as the side surfaces other than the side surfaces 4 and 4 connected to the main blank 30 via the broken line b on the bottom surface 5 and a pair of opposing sides of the bottom surface 5. 6, 6 and two pairs of side surfaces 7, 7,.
7, 7 are connected in series. The shape of the side surfaces 6, 6 is a quadrangle, and like the side surfaces 4, 4, it is a trapezoid that mainly expands upward. However, the shapes of the two pairs of side surfaces 7, 7, 7, 7 are triangular. The polygonal lines b and c correspond to the side surfaces 6, 6, 7, 7, 7,
A perforation or a half cut is preferable so that 7 can be easily bent.

FIG. 13 is a perspective view showing a fourth embodiment of the paper container according to the present invention in which the flange of the main blank has a rounded square shape and the bottom surface of the sub blank has a rounded square shape. As shown in FIG. 14, a paper container D according to the present invention is a main blank composed of a rounded square flange 3 made of paper and a pair of opposed side surfaces 4 and 4 made of paper as a main material. 40, a pair of opposed side surfaces 6, 6, which are side surfaces other than 4, and a side surface 4, 6 connected to the main blank 40, and two pairs of side surfaces 7, 7, 7, 7, connected to the main blank 40. The paper container main body 1 is assembled with the auxiliary blank 41, and the bottom surface 5, the side surfaces 4, 4, 6, 6, 7, 7, 7, 7, 7 and the flange 3 are tightly bonded with a thermoplastic resin film. The container is constituted by providing the inner surface protective film layer 2 by

FIG. 15 is a developed view of a main blank 40 for assembling the paper container body 1 of the paper container D according to the present invention, and FIG. Since these blanks are mainly made of paperboard, they can be easily printed on the surface and have good printing effects.

In the main blank 40 of FIG. 15, a pair of opposed straight sides inside the rounded rectangular flange 3 which is an integral part having no overlapping portion or a seam can be bent via a broken line a. A pair of opposing sides 4, 4
Are connected. The broken line a is preferably perforated or partially cut so that the side surfaces 4 and 4 are easily bent. The shape of the side surfaces 4 and 4 is quadrangular, and is mainly a trapezoid that expands upward, so that a tapered tray shape is obtained after assembly.

In the sub-blank 41 shown in FIG. 16, the side surface 4 connected to the main blank via a polygonal line b is formed between a square bottom surface 5 of a rounded corner and a pair of opposed straight sides of the bottom surface 5 via a broken line b.
A pair of opposing side surfaces 6, 6, which can be bent as side surfaces other than 4, and two pairs of side surfaces 7, 7, 7, 7 are continuously provided on both sides of the side surfaces 6, 6 via a broken line c. The broken line c does not need to be provided. The broken line b is preferably perforated or partially cut so that the side surfaces 6, 6, 7, 7, 7, 7 are easily bent. The shape of the side surfaces 6 and 6 is a quadrangle and, like the side surfaces 4 and 4, a trapezoid that expands mainly upward. However, when the side surfaces 7, 7, 7, and 7 are assembled, the shapes of the rounded flanges 3 and As shown in the figure, the sides corresponding to the corners are arc-shaped so as to be adjacent to the bottom surface 5 of the rounded corner.

In any form of the paper container of the present invention, as shown in FIGS.
Vertical and horizontal (long side, short side) at flanges 0 and 40
In this case, a pair of opposed side surfaces 4 and 4 may be provided continuously on either the long side or the short side. For example, main blank 1
0, 20, 30, 40 and sub blanks 11, 21, 22,
The combination with 31, 32, 41 is as shown in FIG.
A pair of opposed side surfaces 4 and 4 are continuously provided on the long side of the flange 3 of the main blanks 10Y, 20Y, 30Y and 40Y, and the sub blanks 11Y, 21Y, 22Y, 31Y, 32Y and 41Y.
A pair of opposed side surfaces 6 and 6 may be continuously provided on the short side of the bottom surface 5 of the main blank 10T, as shown in FIG.
T, 30T, and 40T, a pair of opposing side surfaces 4, 4 are continuously provided on the short side of the flange 3 to form sub blanks 11T, 21T, 2T.
A pair of opposed side surfaces 6 and 6 may be continuously provided on the long side of the bottom surface 5 of 2T, 31T, 32T and 41T.

In any of the paper containers of the present invention, as shown in FIG. 19, on the inner side of the flange of the main blank, a side other than the side where a pair of opposing side surfaces are continuously provided is provided. A reinforcing piece 8 can be provided. The shape of the reinforcing piece 8 is trapezoidal, semicircular, or the like, and is not particularly limited. The reinforcing piece 8 may be overlapped with either the inner surface or the outer surface of the side surface of the sub blank. By providing the reinforcing piece 8, as shown in FIG. 20, a portion where the main blank and the sub blank overlap each other is provided, and the portion can be reinforced, and the shape of the paper container can be maintained. Thus, the strength of the entire container can be increased.

In any of the embodiments of the paper container of the present invention, the shape of the frame-shaped flange 3 represents the inner periphery of the flange 3. Generally, the shape of the inner circumference and the shape of the outer circumference are the same, but the shape of the inner circumference and the shape of the outer circumference do not necessarily have to be the same. For example, in the fourth embodiment, when the flange of the main blank has a rounded square shape and the bottom surface of the sub blank is also a rounded square shape, the inner periphery of the main blank flange is rounded and the outer periphery is rounded. However, it may be a rectangular shape.

Next, a method for producing a paper container according to the present invention will be described. In this description, mainly the paper container A will be specifically described, but other embodiments can be similarly manufactured.

FIG. 21 is a cross-sectional view schematically showing a molding die in a state where the blank is put in a molding die for vacuum or pressure forming and a semi-finished product constituting a paper container is assembled in the molding die. FIG. 22 is a cross-sectional view schematically showing a mold in a state in which a thermoplastic resin film is closely adhered to the inside of the semi-finished product.

In the present invention, first, FIGS.
As shown in FIG. 1, a main blank 10 composed of a flange 3 and a pair of opposed side surfaces 4 and 4, and a side surface 6 that is a side surface other than the bottom surface 5 not including the flange 3 and a side surface connected to the main blank 10. , 6 are manufactured.

Next, as shown in FIG. 21, the main blank 10 and the sub-blank 11 manufactured as described above are put into a mold 100 for vacuum or pressure forming, and assembled in a tray shape in the mold 100. In the figure, 101 is
A molding machine bed is shown, 102 is a vacuum hole to be sucked, 103 is a thermoplastic resin film, 104
Shows a clamp that clips it.

In order to assemble the paper container main body 1 in the mold 100, first, the main blank 10 is inserted, the flange 3 is firmly fixed to the mold 100, and
Fold 4 inward. Next, the side faces 6 and 6 of the auxiliary blank 11 are bent, and the bottom face 5 is inserted to the bottom face of the molding die 100. By inserting the sub blank 11,
The side surface of the main blank 10 is also pressed into the side surface of the molding die 100, and the paper container main body 1 is formed by the two blanks.
Easy to assemble within zero. When the sub-blank 11 is pushed into the mold 100 during this assembly, the paper container body 1 can be easily assembled in the mold 100 by pushing the plug from above.

Thus, in the paper container main body 1 manufactured as described above, the integral flange 3 having no overlapping portion or seam is formed. Further, the side surfaces 4 and 4 of the blank 10 and the side surfaces 6 and 6 of the blank 20 have a shape rising from the bottom surface 5, and at the corners forming the container, the end portions of the side surfaces 4 and 4 and the other side surfaces 6 and 6 are formed. It is preferable that the end portions are adjacent to each other while being in contact with each other.

Next, in the present invention, as shown in FIG. 22, while suctioning air from the vacuum holes 102 of the molding machine bed 101, the heated thermoplastic resin film 103 is clipped by the clamp 104. The heated thermoplastic resin film 103 is tightly adhered to the inside of the paper container body 1 while the suction is continued while the clamp 104 is lowered to contact the mold 100. At the time of the vacuum forming or the vacuum pressure forming, the softened thermoplastic resin film 103 can be pushed into the paper container body 1 by using a plug assist device together. By adopting such a method, the paper container main body 1
The thickness unevenness of the inner surface protective film layer 2 formed on the inner surface can be reduced, and the quality of the paper container A can be improved. After the close bonding is completed, the suction is released and the thermoplastic resin film 103 is further cut,
The paper container A according to the present invention having the inner protective film layer 2 on the inner surface of the paper container body 1 can be manufactured. The paper containers B, C, D, and E can be manufactured in the same manner as the paper container A.

In the present invention, the paper material constituting the blank is, for example, a basis weight of 150 to 600 g.
/ M @ 2 of various paperboards, processed papers and the like can be used.

In the present invention, the thermoplastic resin film 103 made of a thermoplastic resin for forming the inner surface protective film layer 2 may be made of a thermoplastic resin having water resistance, sealing properties, and heat-fusing properties. Film, for example, various polyethylene (PE), polypropylene (PP), polyvinyl chloride, polyethylene terephthalate (PET), ethylene-vinyl acetate copolymer, ionomer, ethylene-acrylic acid copolymer. Polymer, polyamide, polyvinylidene chloride, polystyrene, saponified ethylene-vinyl acetate copolymer, polycarbonate,
Various thermoplastic resin films such as polybutene, polyvinyl alcohol and others can be used alone or as a laminate. In particular, when a gas barrier property is desired to be imparted to a container, for example, a laminated sheet in which a gas barrier material such as an ethylene-vinyl alcohol copolymer (EVOH) is laminated on an intermediate layer, specifically, PE / EVO
H / PE, PP / EVOH / PE, A (amorphous)
A laminated sheet having a layer structure such as PET / EVOH / PE can be used.

The thickness of the thermoplastic resin film 103 is in the range of 30 to 250 μm, and is appropriately determined depending on the moldability of the film itself, the capacity of the container to be molded, the ratio of deep drawing (depth / diameter), and the like. Determine, but preferably 5
The range is from 0 to 100 μm. However, since the strength of the container is mainly provided by the outer paper container main body 1, the thickness can be extremely reduced as compared with the case of a molded container made of plastic alone. From the viewpoint of environmental friendliness, it is preferable that the thickness be as small as possible in order to reduce the composition ratio of plastics. Since there is a problem, it is necessary to appropriately set it in consideration of the type of the film, the size of the container, and the like.

In the paper container of the present invention, when the thermoplastic resin film 103 is closely adhered to the inner surface of the paper container body 1 which is a semi-finished product, the film itself is adhered in a heated state, Depending on the material of the film 103, the adhesive strength with the paper container body 1 may be insufficient. In such a case, for example, a thermo-adhesive resin such as a heat sealant or a hot melt material is applied to the thermoplastic resin film 103 in advance, or
An adhesive layer can be provided by extrusion coating of a thermo-adhesive resin. When the adhesive layer is applied, the adhesive layer may be provided on the paper container body 1 side. However, when such an adhesive layer is provided, it is necessary to select the material of the adhesive layer and adjust the thickness. It is.

[0060]

Next, the present invention will be described in more detail with reference to specific examples.

Example 1 Using a paperboard having a basis weight of 270 g / m 2, a main blank having a rectangular flange shape as shown in FIG. 3, and a square bottom having a rectangular shape as shown in FIG. A secondary blank was manufactured. This was put into a molding die of a vacuum molding machine as shown in FIG. 21, and the above-mentioned main blank and sub-blank were assembled in the die to obtain a semi-finished paper container main body constituting a paper container. Then, a 50 μm-thick thermoplastic resin film (A
-A film obtained by extruding 20 µm of EVA onto 30 µm of PET film and clipping the same.
Heated to near 0 ° C. Then, the clamp clipping the thermoplastic resin film is brought close to the mold of the vacuum forming machine, brought into contact with the upper part of the paper container body, and heated while sucking from the vacuum holes in the mold. The thermoplastic resin film in the state was put inside the semi-finished product, and was closely adhered to the entire inner surface. After the thermoplastic resin film was closely adhered, the suction was released, and the thermoplastic resin film was further cut to obtain a paper container A having a square flange and a square bottom as shown in FIG. . Paper container A obtained above
By filling the contents into the container and heat-sealing the sealing lid to the flange, a product having sufficient sealing properties could be obtained. After use, it could be discarded as combustion waste.

Example 2 Using a paperboard having a basis weight of 270 g / m 2, a main blank having an octagonal inner peripheral shape as shown in FIG. 6 and a bottom surface as shown in FIG. An octagonal sub-blank was produced. Example 1
Similarly, a semi-finished paper container main body constituting a paper container is obtained by putting the main blank and sub-blank in the molding die of a vacuum molding machine as shown in FIG. Was. Then, in the same manner as in Example 1, a 50 μm-thick thermoplastic resin film (A-PET film 30 μm having an EV
A film extruded and coated with A20 μm) was put into the inside of a semi-finished paper container body, and was tightly adhered to the entire inner surface thereof. After the thermoplastic resin film adheres tightly, release the suction, cut the thermoplastic resin film further,
A paper container B having an octagonal flange and an octagonal bottom as shown in FIG. 5 was obtained. By filling the contents into the paper container obtained above and heat sealing the sealing lid to the flange, a product having sufficient sealing properties could be obtained.
After use, it could be discarded as combustion waste.

Example 3 Using a paperboard having a basis weight of 270 g / m 2, a main blank having a square inner peripheral shape as shown in FIG. 3 and a bottom surface shape as shown in FIG. 11 were used. Produced an octagonal sub-blank. This is put in a mold of a vacuum forming machine as shown in FIG. 21 in the same manner as in Example 1, and the above-mentioned main blank and sub-blank are assembled in the mold to form a semi-finished paper constituting a paper container. A container body was obtained. Then, in the same manner as in Example 1, a 50 μm-thick thermoplastic resin film (A-PET film 30 μm having an EV
A film extruded and coated with A20 μm) was put into the inside of a semi-finished paper container body, and was tightly adhered to the entire inner surface thereof. After the thermoplastic resin film adheres tightly, release the suction, cut the thermoplastic resin film further,
A paper container C having a rectangular flange and an octagonal bottom as shown in FIG. 9 was obtained. By filling the contents into the paper container C obtained above and heat-sealing the sealing lid to the flange, a product having sufficient sealing properties could be obtained. After use, it could be discarded as combustion waste.

Example 4 Using a paperboard having a basis weight of 270 g / m 2, as shown in FIG. 15, the inner peripheral shape of the flange was a square main blank with rounded corners, and as shown in FIG. A quadrangular sub-blank having a round bottom with rounded corners was manufactured. This is put in a mold of a vacuum forming machine as shown in FIG. 21 in the same manner as in Example 1, and the above-mentioned main blank and sub-blank are assembled in the mold to form a semi-finished paper constituting a paper container. A container body was obtained. Then, in the same manner as in Example 1, a 50 μm-thick thermoplastic resin film (a film obtained by extruding and coating EVA 20 μm on an A-PET film 30 μm) is put into a semi-finished paper container main body, and closely adhered to the entire inner surface thereof. I wore it. After the thermoplastic resin film is closely adhered, the suction is released, and the thermoplastic resin film is further cut. As shown in FIG. 13, the flange is made of paper having a square shape with a rounded corner and a square bottom with a rounded corner. Container D was obtained. By filling the contents into the paper container D obtained above and heat-sealing the sealing lid to the flange, a product having sufficient sealing properties could be obtained. After use, it could be discarded as combustion waste.

[0065]

As is apparent from the above description, the present invention comprises a frame-shaped flange made of paper as a main material and a pair of opposing side surfaces connected to each other through a broken line inside the flange. Main blank, to produce a sub blank consisting of a bottom surface and side surfaces other than the side surfaces connected to the main blank,
This is placed in a molding die for vacuum or pressure forming, assembled in the mold to assemble a paper container main body, which is a semi-finished product constituting a paper container, and a bottom surface, a side surface and a flange constituting the paper container main body. And a film made of a thermoplastic resin in a heated state is closely adhered to each other to fix them, thereby producing a paper container. Therefore, the present invention has improved the problem that the sealability of the seal by the seal lid is insufficient as in the prior art, and has completely changed the manufacturing process. That is, a main blank and a sub-blank mainly made of paperboard are manufactured, and these are assembled in a mold for vacuum or air pressure forming of a film, and thereafter, the entire surface of the inner surface is vacuum-formed or air-pressure formed, or a combination thereof. It is merely molded and the thermoplastic resin film is adhered tightly, and since the flange is a smooth integral body without overlapping portions or joints, it is possible to sufficiently seal the contents with a seal lid. Further, it is easy to assemble simply by inserting a main blank consisting of a flange and a side surface and a sub blank consisting of a bottom surface and a side surface into a molding die, and the assembled shape is not easily deformed. Furthermore, since the paper container of the present invention is a container mainly made of paper, it can be discarded as burning garbage as it is after use as a container, and does not cause environmental destruction or the like. INDUSTRIAL APPLICABILITY The paper container according to the present invention is extremely useful as a container for packaging frozen foods, prepared foods and the like.

[Brief description of the drawings]

FIG. 1 is a perspective view showing one embodiment of a paper container according to the present invention.

FIG. 2 is a perspective view schematically showing a paper container main body constituting the embodiment of FIG. 1;

FIG. 3 is a development view showing a main blank of the embodiment of FIG. 1;

FIG. 4 is a development view showing a sub blank of the embodiment of FIG. 1;

FIG. 5 is a perspective view showing an example of another embodiment of the paper container of the present invention.

FIG. 6 is a development view showing a main blank of the embodiment of FIG. 1;

FIG. 7 is a development view showing a sub blank of the embodiment of FIG. 1;

FIG. 8 is a development view showing another sub blank of the embodiment of FIG. 1;

FIG. 9 is a perspective view showing an example of still another embodiment of the paper container of the present invention.

FIG. 10 is a development view showing a main blank of the embodiment of FIG. 9;

FIG. 11 is a development view showing a sub blank according to the embodiment of FIG. 9;

FIG. 12 is a development view showing another sub blank of the embodiment of FIG. 9;

FIG. 13 is a perspective view showing an example of still another embodiment of the paper container of the present invention.

FIG. 14 is a perspective view schematically showing a paper container main body constituting the embodiment of FIG.

FIG. 15 is a development view showing a main blank of the embodiment of FIG. 13;

FIG. 16 is a development view showing a sub blank according to the embodiment of FIG. 13;

FIG. 17 is a development view showing a combination of a main blank and a sub blank constituting the paper container of the present invention.

FIG. 18 is a developed view showing another combination of the main blank and the sub blank constituting the paper container of the present invention.

FIG. 19 is a development view showing an example of the paper container according to the embodiment of the present invention, in which a reinforcing piece is provided.

FIG. 20 is a perspective view showing an example of the paper container according to the embodiment of the present invention in which a reinforcing piece is provided.

FIG. 21 is a cross-sectional view schematically showing a molding die in a state in which a paper container main body, which is a semi-finished product, constituting an embodiment of the paper container of the present invention is assembled.

FIG. 22 is a cross-sectional view schematically showing a mold in a state in which a thermoplastic resin film is tightly adhered to the inside of a paper container main body, which is a semi-finished product constituting one embodiment of the paper container of the present invention.

[Explanation of symbols]

 Reference Signs List A paper container B paper container C paper container D paper container E paper container 1 paper container main body 2 inner protective film layer 3 flange (main blank) 4 side (main blank) 5 bottom (sub blank) 6 side (Sub-blank) 7 Side surface (sub-blank) 8 Reinforcement piece (main blank) 10 Main blank 11 Sub-blank 20 Main blank 21 Sub-blank 22 Sub-blank 30 Main blank 31 Sub-blank 32 Sub-blank 40 Main blank 41 Sub-blank a Bending line b Folded line c Folded line 100 Mold 101 Molding machine bed 102 Vacuum hole 103 Thermoplastic resin film 104 Clip

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Yuji Sugiyama, 1-1-1, Ichigaya Kagacho, Shinjuku-ku, Tokyo Inside Dai Nippon Printing Co., Ltd. (72) Inventor Takataka Aoki Ichigaya, Ichigaya-cho, Shinjuku-ku, Tokyo No. 1-1, Dai Nippon Printing Co., Ltd. (72) Inventor Taku Furuta 1-1-1, Ichigaya Kagacho, Shinjuku-ku, Tokyo F-term in Dai Nippon Printing Co., Ltd. 3E060 AA08 AB12 AB32 BC01 BC04 DA21 EA13 3E067 AA11 AB01 BA10A BB01A BB14A BC02A CA07 CA24 EA06 FA01 FC01 3E084 AA05 AA14 AA24 AA34 AB10 BA01 FD13 HD01

Claims (9)

[Claims] 1. A main blank made of paper as a main material, comprising a frame-shaped flange and a pair of opposing side surfaces connected to the inside of the flange via a broken line, and a main blank connected to the main blank. A paper container body assembled with a sub blank consisting of a side surface other than the side surface, and an inner protective film layer made of a thermoplastic resin film that is tightly adhered to the inner surface of the paper container body. Characterized paper container. 2. The paper container according to claim 1, wherein the frame-shaped flange of the main blank has a polygonal shape, and the bottom surface of the sub-blank has a polygonal shape. 3. The sub-blank comprises the bottom surface and the side surface other than the side surface connected to the main blank connected to the bottom surface through a broken line. 6. The paper container according to 1. 4. The sub-blank comprises the bottom surface, and a pair of opposed side surfaces other than the side surface connected to the main blank connected to the bottom surface through a broken line, and is provided on both sides of the side surface. The paper container according to claim 1 or 2, wherein the side surface is further provided continuously through a polygonal line. 5. The main blank, wherein the shape of the flange is square, and a pair of opposing side surfaces are continuously provided inside the flange via a polygonal line, and the sub-blank is formed on the bottom surface. Is an octagon, a pair of opposing quadrangular sides other than the side connected to the main blank via a polygonal line on the bottom surface, and two pairs of opposing triangular sides are connected in series. 3. The method according to claim 2, wherein
6. The paper container according to 1. 6. The main blank, wherein the shape of the flange is quadrangular, and a pair of opposing side surfaces are continuously provided inside the flange via a polygonal line, and the sub-blank is formed on the bottom surface. Is an octagon, and a pair of opposing square sides other than the side faces connected to the main blank via a broken line on the bottom surface, and a triangle connected to both sides of the side faces via a broken line. The paper container according to claim 2, wherein the paper container is connected to the side surface of the paper container. 7. The main blank, wherein the shape of the flange is a square with rounded corners, and a pair of opposing side surfaces are continuously connected to a straight side inside the flange via a polygonal line, The sub-blank has a shape of the bottom surface which is a square with rounded corners, and a pair of opposed side surfaces other than the side surface connected to the main blank via a broken line on a straight side of the bottom surface; The paper container according to claim 1, wherein side surfaces are continuously provided on both sides. 8. A reinforcing piece is provided on an inner side of the flange of the main blank other than a side on which the pair of opposed side surfaces are connected via a broken line. 8. The paper container according to any one of 1 to 7. 9. A main blank made of paper as a main material, comprising a frame-shaped flange and a pair of opposing side faces continuously connected to the inside of the flange via a broken line, and a bottom face connected to the main blank. A sub blank consisting of a side surface other than the side surface is placed in a molding die for vacuum or air pressure molding, a paper container body as a semi-finished product is assembled in the molding die, and the thermoplastic resin film in a heated state is evacuated. A method for producing a paper container, wherein the inner surface of the paper container body is tightly adhered to the entire inner surface of the paper container body by molding by pressurization or a combination thereof.