JP6060561B2 - Cup type paper container - Google Patents

Description

  The present invention relates to a cup-type paper container, and more particularly to a cup-type paper container having a reduced level difference in a flange portion for sealing a lid member.

  2. Description of the Related Art Paper containers that are flattened by crushing the opening of a paper cup to form a flange part and sealed with a lid material are widely used mainly for storing beverages and the like. When a beverage is stored, the lid can be peeled off, or a straw can be stabbed into the lid and used as a cup for drinking, which is convenient.

  For disposable paper cups that are intended for temporary use, there is no major problem even if the end surface of the paper comes into contact with the contents, but when used as a paper container with storage, the contents can be removed from the end surface of the paper. In order to prevent penetration, at least the inner end face of the container must be protected in some way.

  The manufacturing method of the water-resistant container described in Patent Document 1 filed by the present applicant has been made to solve this problem. A window is opened on a portion of the paperboard corresponding to one seam end of the joint of the container, a thermoplastic resin film is laminated on the entire surface of the paperboard including the window, cut into a blank shape, and then the film of this window Is folded back to the end of the blank paper to protect the end face.

  On the other hand, in a cup-shaped paper container, a flange is formed by rounding a blank cut out in a fan shape into a cylindrical shape, joining both left and right ends, curling the upper end outward, rounding, and further crushing. If a fan-shaped blank is used, the paper thickness increases at the joint portion of the body portion, so that a step is generated in the flange portion. If there is a step in the flange portion, there is a problem that a sealing failure is likely to occur in the step portion when the lid member is sealed.

  The cup-shaped paper container and the manufacturing method thereof described in Patent Document 2 filed by the applicant of the present application are made for the purpose of reducing the step of the flange portion, and the upper side edge of the fan-shaped body blank. Is cut into a triangle, thereby reducing the overlap of paper in the flange portion and reducing the level difference in the flange portion.

Japanese Patent Publication No.58-43264 JP 2008-222244 A

  According to the method described in Patent Document 2, the level difference of the flange portion is considerably improved. On the other hand, when trying to impart long-term storage stability, retort suitability, etc. to the cup-type container, a paper base material is used. Since the thermoplastic resin layer to be laminated on has a complicated structure including a gas barrier layer and the like, the total thickness of the laminated body becomes thick, and the step of the flange portion has become a problem again.

  The problem to be solved by the present invention is to propose a cup-type paper container having a flange portion having an improved step on the upper surface of the flange-type paper container.

As means for solving the above-mentioned problems, the invention described in claim 1 includes a paper body and a cylindrical body formed from a laminate having a thermoplastic resin layer provided on both sides of the paper layer. A cup-type paper container comprising a bottom part for sealing an opening below the body part and a lid member for sealing the opening above the body part so that the opening can be opened;
The body part is formed by rolling the upper end part of the body part one or more times outside and then flatly crushing the body part laminating part where both side edges of the body part forming blank are overlapped and sealed. Having a flanged portion,
The upper part of the left and right side edges of the body part forming blank has a corner cut part cut out in a triangle, and the side part edge on the inside of the container in the body part bonding part, from the paper layer The extended thermoplastic resin layer is folded outward, and in the corner cut part at the top of the side edge, there is no paper layer at the intersection of the side edge and the corner cut part. A triangular resin part consisting only of a resin layer is formed ,
Length of the side overlapping the side edges of the inner container of the triangular resin portion (B) is a Der Rukoto 50% to 110% or less of the flange portion of the width (W) in a cup paper container, wherein is there.

  The cup-type paper container according to the present invention is intended to solve the problem that the step of the flange portion is caused by the laminate being doubled on the upper portion of the body portion bonding portion when forming the flange portion. It is. In addition to the conventional corner cuts on the left and right side edges, there is no paper layer at the intersection of the side edge and the corner cut part at the inner corner cut part, only from the thermoplastic resin layer Since the triangular resin portion is formed, when the flange portion is formed, the thermoplastic resin layer of the triangular resin portion melts and enters the step portion, so that the step is buried and the flange portion is finished flat.

  Delete.

Further, in the invention according to claim 2 , the bottom surface portion has a peripheral portion bent downward, and the bottom surface portion is formed on the lower folded portion formed by folding the lower end portion of the body portion inward. in a state where the peripheral portion of is inserted, and a lower end of the barrel, a cup paper container according to claim 1, characterized in that the peripheral portion of the bottom portion to form a bottom sleeve in close contact seal is there.

Further, in the invention according to claim 3, after the lower end portion of the body portion is folded inward to form the lower folded portion, the bottom portion is further folded toward the peripheral edge portion of the bottom surface portion to be tightly sealed. The cup-type paper container according to claim 2 , wherein a sleeve is formed.

The invention described in Claim 4 is a cup paper container according to claim 1, characterized in that the formation of the bottom portion is folded at the bottom of the blank for forming the body portion.

The invention according to claim 5 is characterized in that, in the body part laminating part, a side edge which is the outside of the container of the body part forming blank is covered with the thermoplastic resin layer. It is a cup type paper container given in any 1 paragraph of Claims 1-4 .

The invention according to claim 6 is the cup type paper container according to any one of claims 1 to 5 , wherein the thermoplastic resin layer on the inner surface side of the container includes a gas barrier layer.

  In the cup-shaped paper container according to the present invention, in addition to the corner cuts on the left and right side edges, in the corner cut part on the inner side, there is no paper layer at the intersection of the side edge and the corner cut part, and the thermoplastic resin Since the triangular resin portion consisting only of the layers is formed, when the flange portion is formed, the thermoplastic resin layer of the triangular resin portion melts and enters the step portion, so that the step is filled and the flange portion is finished flat. . In addition, by optimizing the position and shape of the triangular resin portion, it is possible to stably obtain a flat flange portion.

Also, the length of the side overlapping the side edges of the inner container of the triangular resin part (B), by at most 110% 50% or more of the flange width (W), the occurrence of sealing failure It can be prevented in advance.

In the second aspect of the invention, a paper container having a general paper cup shape having a bottom sleeve can be provided.

Further, in the invention according to claim 3 , since the lower end portion of the body portion is folded inward to form the lower folded portion, the lower end portion is further folded toward the peripheral portion of the bottom surface portion and hermetically sealed. The end face of is not exposed. For this reason, the water resistance of the container is improved.

Further, in the invention of claim 4 , since the bottom portion is formed by folding the lower part of the blank forming the body portion, a paper container having a flat bottom surface without a bottom sleeve is obtained, particularly heating by a microwave oven. Sometimes, it is possible to obtain a paper container in which the bottom portion is hardly burnt.

According to the invention described in claim 5 , since the side edge which is the outside of the container of the body forming blank is covered with the thermoplastic resin layer in the body part bonding part, the water resistance of the container Improves.

According to the invention described in claim 6 , since the thermoplastic resin layer on the inner surface side of the container includes the gas barrier layer, a paper container capable of long-term storage can be realized. By combining with the invention according to claim 3 and the invention according to claim 5 , it is possible to make a structure in which the end portion of the paper layer is not exposed at all, so that a container for retort food can be obtained.

FIG. 1 is a perspective view showing a basic embodiment of a cup-type paper container according to the present invention. FIG. 2A is a schematic cross-sectional view showing the A-A ′ cross section of FIG. 1. FIG. 2 (2) is an enlarged cross-sectional schematic diagram of the trunk. FIG. 2 (3) is an enlarged schematic cross-sectional view of the bottom surface. FIG. 3A is a schematic cross-sectional view showing the B-B ′ cross section of FIG. 1. FIG. 3 (2) is an enlarged schematic cross-sectional view of a body bonding portion. FIG. 4 is a schematic plan view showing the trunk forming blank and the bottom forming blank of the cup-type paper container shown in FIG. 1. FIG. 5 is an explanatory view showing the process of forming the flange portion, and FIG. 5 (1) is an enlarged view of the upper end portion of the body portion bonding portion. FIG. 5B is a schematic cross-sectional view showing a state where the upper end portion of the body portion is curled. FIG. 5 (3) is a schematic cross-sectional view showing a state in which the flange portion is formed by crushing it. FIG. 6 is a schematic cross-sectional view showing the C-C ′ cross section of FIG. FIG. 7 is an explanatory diagram of a triangular resin portion. FIG. 7 (1) shows that when the length (B) of the side overlapping the side edge that is the inside of the container of the triangular resin part is 100% of the width (W) of the flange part, FIG. In the case of 50%, FIG. 7 (5) is an explanatory view showing the case of 110%, and (2), (4) and (6) are schematic diagrams showing the state in which each is molded into a flange. FIG. FIG. 8 is an explanatory view showing a method of forming a thermoplastic resin layer on the side edge of the trunk forming blank. FIG. 9 is a partially enlarged view of FIG. 8, and is an explanatory view showing a method for forming a triangular resin portion in particular. FIG. 10 is a schematic cross-sectional view showing another embodiment of the cup-type paper container according to the present invention. FIG. 11 is a schematic cross-sectional view showing a state of the body bonding portion in the embodiment shown in FIG. FIG. 12 is a schematic cross-sectional view showing another embodiment of a laminate constituting a paper container. FIG. 13 is a perspective view showing another embodiment of the cup-type paper container according to the present invention and a plan view of the blank. FIG. 14 is a schematic cross-sectional view showing a longitudinal section of a flange portion including a body pasting portion in a conventional cup-type container.

Hereinafter, the cup type paper container according to the present invention will be described in detail with reference to the drawings.
FIG. 1 is a perspective view showing a basic embodiment of a cup-type paper container according to the present invention. FIG. 2A is a schematic cross-sectional view showing the AA ′ cross section of FIG. FIG. 2 (2) is an enlarged cross-sectional schematic diagram of the trunk. FIG. 2 (3) is an enlarged schematic cross-sectional view of the bottom surface. FIG. 3A is a schematic cross-sectional view showing the BB ′ cross section of FIG. FIG. 3 (2) is an enlarged schematic cross-sectional view of a body bonding portion. FIG. 4 is a schematic plan view showing the trunk forming blank and the bottom forming blank of the cup-type paper container shown in FIG. 1. FIG. 5 is an explanatory view showing a process of forming the flange portion. FIG. 6 is a schematic cross-sectional view showing a CC ′ cross-section of FIG. 1, that is, a vertical cross-section of a flange portion including a body portion bonding portion. FIG. 7 is an explanatory diagram of a triangular resin portion. The following description will be made with reference mainly to these figures.

  A cup-shaped paper container (1) according to the present invention comprises a cylindrical body (2) formed from a laminate having a paper layer (2) and thermoplastic resin layers (3a, 3b) provided on both sides of the paper layer. 20), a bottom (30) for sealing the lower opening of the body (20), and a lid (10) for sealing the upper opening of the body (20) so that the opening can be opened. It is.

  The body part (20) has the body part laminating part (21c) on which both side edges of the body part forming blank (20b) are overlapped and sealed, and the upper end part (23) of the body part (20) on the outside. It has a flange portion (FL) formed by being wound once or more and then flattened. In the example shown in FIG. 2 (1), the upper end portion (23) is wound around the outer half once and then flattened to form a flange portion.

  The cup-type paper container (1) according to the present invention has corner cut portions (25a, 25b) cut into triangles on the upper left and right side edges (21a, 21b) of the body forming blank (20b). Then, the thermoplastic resin layers (3a, 3b) extended from the paper layer (2) are folded outward at the side edge (21b) which is inside the container in the body bonding portion (21c). In the upper corner cut portion (25b) of the side end edge (21b), there is no paper layer at the intersection of the side end edge (21b) and the corner cut portion, and the triangle is composed only of the thermoplastic resin layer. A resin portion (26) is formed.

  In the embodiment shown in FIG. 1, as shown in FIG. 4, the cup-type paper container (1) is composed of a body forming blank (20 b) and a bottom surface forming blank (30 b). (20) is a body part bonding part (21c) in which both side edges (21a, 21b) of the body part forming blank (20b) are overlapped and sealed, and a lower end part (22) of the body part (20). ) Inwardly, and the bottom part (30) has a peripheral part (31) bent downward, and the lower part of the trunk part (20). (22a), with the peripheral edge (31) of the bottom face inserted, the lower end (22) of the trunk and the peripheral edge (31) of the bottom face are tightly sealed, and the bottom sleeve (BS) is attached. Forming.

  As shown in FIGS. 3 (2) and 4, the thermoplastic resin layers (3a, 3b) extending from the side edge of the paper layer (2) are located outside the container at the side edge of the paper layer. By being folded, the side edge of the paper layer is protected by the thermoplastic resin layer. In addition, FIG. 4 is the figure which looked at the trunk | drum formation blank (20b) from the surface used as the inner side of the container of a laminated body.

  FIG. 5 is an explanatory view showing a process of forming the flange portion (FL), and FIG. 5 (1) is an enlarged view of the upper end portion (23) of the body portion bonding portion. FIG. 5B is a schematic cross-sectional view showing a state where the upper end portion of the body portion is curled. FIG. 5 (3) is a schematic cross-sectional view showing a state in which the flange portion is formed by crushing it. FIG. 5 (1) is a view as seen from the inner side surface of the container, and the inner thermoplastic resin layer (3b) is omitted to avoid complication.

  FIG. 5 (1) shows which positions of the body forming blank (20b) are folded and finally become the flange outer edge (23a) and the flange inner edge (23b) of the flange (FL). It is indicated by a one-dot chain line. In this example, since the upper end part (23) of the trunk part is wound once and a half, the folding position is three places, and the flange part (FL) is in a state where the laminate is overlapped in three layers. Yes.

  In order to complete the seal with the lid member (10) in the flange portion (FL), at least a part of the upper surface of the flange portion (FL) needs to be flat, but the upper end portion of the curled barrel portion When crushing (23) to form the flange portion (FL), the thermoplastic resin layer (3b) inside the laminate appears on the top surface of the flange portion. At this time, a step (24) inside the container of the trunk portion bonding portion (21c) appears on the upper surface of the flange portion.

  FIG. 14 is a schematic cross-sectional view showing a longitudinal section of a flange portion (FL) including a body portion pasting portion of a conventional cup-type container.

  Also in the conventional cup-type container, in order to protect the side edge (21e) of the paper layer, which is the inside of the container, the thermoplastic resin layer (3b) faces the outside of the container. However, since this is merely performed for the purpose of protecting the end face of the paper layer, it was wound so as to be in close contact with the side edge of the paper layer as shown in the figure.

  As a result, as shown in FIG. 14, in the step (24) portion of the flange portion (FL), the amount of resin sufficient to flatten the upper surface of the flange portion is insufficient, and voids may occur.

  FIG. 6 is a schematic cross-sectional view showing the C-C ′ cross section of FIG. 1 at the same position as FIG. 14, that is, a vertical cross section of the flange portion (FL) including the body bonding portion (21 c). At this position of the flange part (FL), there is a part where a maximum of 4 laminates overlap, so it is impossible to mold the flange part (FL) to the same thickness over the entire circumference. However, at least a part of the upper surface of the flange portion can be flattened by filling the step (24) of the joint of the laminate with a thermoplastic resin.

  In the side edge (21b) which is the inside of the container of the trunk portion forming blank (20b) in the trunk portion laminating portion (21c), at the intersection of the side edge (21b) and the corner cut portion (25b), There is no paper layer (2), and a triangular resin portion (26) consisting only of the thermoplastic resin layers (3a, 3b) is formed.

  Since the triangular resin part (26) is present at the side edge of the paper layer (2) located on the upper surface of the flange part (FL), this thermoplasticity is obtained when the flange part (FL) is molded by heating and pressing. The resin layer exhibits the effect of filling the step (24) of the flange portion.

FIG. 7 is an explanatory diagram of the triangular resin portion (26).
The triangular resin portion (26) is a triangular portion determined by a side overlapping the side end edge (21b) that is an extension line of the side end edge (21b) and a hypotenuse that is a part of the corner cut portion (25b). In this portion, the paper layer (2) does not exist, and only the thermoplastic resin layers (3a, 3b) on the front and back surfaces of the paper layer are overlapped.

The shape and size of the triangular resin portion (26) are the length (A) of the hypotenuse and the side length (B) that overlaps the side edge (21b), and the other side and the side edge (21b). It is determined by the angle (θ) formed by the side.

FIG. 7 (1) shows a case where the length (B) of the side overlapping the side edge (21b) on the inside of the container of the triangular resin part (26) is 100% of the width (W) of the flange part. 7 (3) is an explanatory view showing the case of 50%, and FIG. 7 (5) is an explanatory view showing the case of 110%, and (2), (4), and (6) are each molded into a flange. It is the schematic diagram which showed the state when seeing the state which carried out diagonally from the container inner side.

The length (B) of the side overlapping the side edge (21b) that is the inner side of the container of the triangular resin part (26) may be experimentally in the range of 20% to 150% of the width (W) of the flange part. For example, it was found that a portion having no step was generated on the upper surface of the flange portion, and the sealing property of the lid member (10) was secured.

However, when the length (B) of the side overlapping the side edge (21b) which is the inner side of the container of the triangular resin part (26) is less than 50% of the width (W) of the flange part, When the sealing property becomes unstable and exceeds 110%, the body part bonding portion (21c) under the flange part is affected, which may cause a seal failure of the body part bonding part.

For this reason, as a more preferable range of the length (B) of the side overlapping the side edge (21b) which is the inner side of the container of the triangular resin portion (26 ), 50% or more and 110% of the width (W) of the flange portion. The following is the most preferable.

  Further, if the angle (θ) of the triangular resin portion is too large, the dimension (A) becomes too large, and the rigidity tends to be insufficient when the corner cut portion is formed on the flange. On the other hand, if it is too small, the amount of resin is insufficient and the effect of flattening the upper surface of the flange portion is reduced.

  For this reason, it is preferable that the angle (θ) of the triangular resin portion is in a range of approximately 30 ° to 45 °.

As shown in FIG. 3 (2), the thermoplastic resin layer that extends from the inner side edge (21b) and is folded back in the trunk portion laminating portion (21c) is thermoplastic inside the paper layer. Resin layer (3
b) and the thermoplastic resin layer (3a) outside the paper layer may be combined, or depending on the method for extending the thermoplastic resin layer described later, the thermoplastic resin layer (3b) inside the paper layer may be used. There can be only cases.

  FIG. 8 is an explanatory view showing a method of forming a thermoplastic resin layer on the side edge of the body portion forming blank (20b). The figure has shown the state which looked at the trunk | drum formation blank (20b) from the container outer surface.

  First, as shown in FIG. 8 (1), the deformed long window (5) is punched out in the web (2w) of the base paper to make a hole. At this stage, although not shown in the figure, since the necessary printing has already been performed on the base paper, the long window is punched out in synchronization with the printed pattern. The inner side of the deformed long window (5) is provided at a position that finally becomes the side edge (21b) of the trunk forming blank (20b).

  The thermoplastic resin layers (3a) and (3b) are bonded to the front and back surfaces of the web (2w) of the base paper. The thermoplastic resin layers (3a) and (3b) may be a single layer or may be composed of a plurality of layers. In the case of a plurality of layers, at least the outermost surface needs to be a material that can be heat-sealed.

  A body forming blank (20b) is punched out from the laminated body in which the bonding is completed. The blank forming shape (20c) for trunk | drum formation is shown with the dotted line. At this time, the side edge (21b) side includes the side edge (21b) as shown in FIG. 8 (2) by including a part of the thermoplastic resin layer formed in the long window (5). ) From which the thermoplastic resin layers (3a) and (3b) are extended to form a protruding portion (3c).

  As shown in FIG. 8 (3), the extended thermoplastic resin layer is folded back to the outer surface side at the side edge (21b) to obtain a folded thermoplastic resin layer (3d). The body part forming blank (20b) is obtained.

  If the timing of providing the deformed long window (5) is after the outer thermoplastic resin layer (3a) is formed, a blank in which only the inner thermoplastic resin layer (3b) is extended can be obtained.

  Although not particularly illustrated, if the deformed long window (5) is provided at the side edges on both sides of the body forming blank (20b), the inner surface of the body bonding part (21c) as described later A container in which not only the side but also the end surface on the outer surface side is protected can be obtained.

  FIG. 9 is a partially enlarged view of FIG. 8, and is an explanatory view showing a method of forming the triangular resin portion (26) in particular. As shown in FIG. 9 (1), the deformed long window (5) is punched into the web (2w) of the base paper. The thickened portion at the top of the deformed long window (5) is provided with a portion that should become one side of the triangular resin portion (26).

  When punching is performed at a predetermined position in accordance with the blank punching shape (20c) for forming the body portion, as shown in FIG. 9 (2), the protruding portion (3c) of the thermoplastic resin layer extends from the side edge (21b). Thus, the body forming blank (20b) is obtained. At this time, a portion to be the triangular resin portion (26) is formed in the corner cut portion (25b).

Next, as shown in FIG. 9 (3), the protruding portion is folded back to the surface side along the side edge (21b) to form the folded thermoplastic resin layer (3d). At the same time, the triangular resin portion (25) Is formed. As can be seen from the drawing, the thermoplastic resin layer is folded twice in part of the triangular resin portion (26). This means that a sufficient amount of resin for filling the step on the upper surface of the flange portion is secured, which is preferable.

  FIG. 10 is a schematic cross-sectional view showing another embodiment of the cup-type paper container (1) according to the present invention. FIG. 11 is a schematic cross-sectional view showing a state of the body portion bonding portion (21c) in the embodiment shown in FIG. In the embodiment shown in FIG. 10 and FIG. 11, in the trunk | drum bonding part (21c), it becomes not only the side edge (21b) used as the inner side of a container but the outer side of a container. The side edge (21a) is also covered with the thermoplastic resin layer, and after the lower end of the body is folded inward to form the lower folded portion (22a), the peripheral edge ( 31), the lower end winding portion (22b) is formed, and the bottom sleeve (BS) is formed by tightly sealing.

  The flange portion (FL) also has a structure in which the end surface of the paper is not exposed to the outside by winding the upper end portion (23) of the body portion once and a half.

  In the embodiment shown in FIG. 10 and FIG. 11, the end portions of the paper layer are all protected by the thermoplastic resin layer, or are wound and not exposed to the outside. In addition, the outer surface can be a water-resistant container. Moreover, it can also be set as the paper container in which a retort sterilization process is possible by using a resin material with high heat resistance, and a gas barrier layer.

FIG. 12 is a schematic cross-sectional view showing another embodiment of a laminate constituting a paper container.
In the embodiment shown in FIG. 12, the gas barrier layer (4) is laminated between the paper layer (2) and the thermoplastic resin layer (3b) on the inner surface side. When a laminated body contains a gas barrier layer (4), the preservability over a long period of time can be provided to a paper container.

  FIG. 13: is the perspective view which showed the other embodiment of the cup type paper container (1) based on this invention, and the top view of the blank (20b). The embodiment shown in FIG. 13 is characterized in that the bottom part (30) is formed by folding the lower part of the blank (20b) forming the body part (20).

  The cup-shaped paper container (1) shown in FIG. 13 has no bottom sleeve and has a flat bottom surface. For this reason, it is possible to avoid the problem that the bottom sleeve is burnt, particularly during heating by a microwave oven.

Next, materials used for the cup-shaped paper container according to the present invention will be described.
For the paper layer (2), paper having a basis weight of 200 to 500 g / m 2 and a density of about 0.6 to 1.1 g / cm 3 can be used. Carton base paper using 100% virgin pulp and cup base paper can be preferably used. White cardboard, coated cardboard, ivory paper, and the like can also be used.

  As the thermoplastic resin layer, in the case of a single layer, a thermoplastic resin of a heat sealable material is used. For example, low density polyethylene resin (LDPE), medium density polyethylene resin (MDPE), linear low density polyethylene resin (LLDPE), ethylene / vinyl acetate copolymer, ethylene / α-olefin copolymer, ethylene- Ethylene resin such as methacrylic acid resin copolymer, blend resin of polyethylene and polybutene, homopolypropylene (CPP), propylene / ethylene random copolymer, propylene / ethylene block copolymer, propylene / α-olefin copolymer In addition to polypropylene resin such as coalescence, unstretched polyethylene terephthalate (PET) resin and the like can be used.

The thermoplastic resin layer may be a multilayer film in which other materials are bonded so that the heat-sealable material is on the outside. Specifically, a PET resin film (hereinafter simply referred to as PET; the same applies to other abbreviations), a polyamide resin (nylon resin) film, a PP film, and the like. The gas barrier layer is also included.

  As the gas barrier layer, it is oxidized to a gas barrier film such as aluminum foil, aluminum vapor-deposited PET, polyvinylidene chloride film, polyvinyl alcohol film, ethylene vinyl alcohol copolymer film, gas barrier nylon film, gas barrier PET film, or PET film. Inorganic oxide vapor-deposited film on which inorganic oxides such as aluminum and silicon oxide are deposited, polyvinylidene chloride coating, film containing water-soluble resin and inorganic layered compound, metal alkoxide or its hydrolyzate and isocyanate compound react A gas barrier coating layer such as a resin layer made of a coated film can be used.

For laminating each of these layers and the paper layer, a dry laminating method using a known adhesive or an extrusion laminating method in which a molten resin is extruded and bonded is used.
Hereinafter, the cup-type paper container according to the present invention will be described more specifically based on examples, but the present invention is not limited thereto.

After printing a pattern on the surface of a cup base paper having a basis weight of 260 g / m ² , a deformed long window as shown in FIG. 8 (1) was punched in accordance with the pattern. After a laminate of (PE 12 μm / silica vapor-deposited PET 12 μm / LDPE 60 μm) was bonded to the back side of the base paper, which is the inner surface side of the container, by a sandwich lamination method using polyethylene resin (15 μm), An LDPE layer having a thickness of 20 μm was formed. The resin on the front and back surfaces of the deformed long window part was bonded together. Next, punching is performed using a punching die, and as shown in FIG. 8 (2), the body part forming blank in which the thermoplastic resin layer extends from the side edge (21b) to be inside the container in the body part bonding part. (20b) was created.

Next, as shown in FIG. 8 (3), the side edge (21b) is made of the thermoplastic resin by folding the thermoplastic resin layer extending from the side edge (21b) of the body forming blank to the outside of the container. While protecting by the layer, the triangular resin part (26) was formed. By changing the angle (θ) of the triangular resin part to be constant (35 °) and changing the length (B) of the side overlapping the side edge (21b) inside the container of the triangular resin part (26), Samples 1-9 were made.

The blank was molded using a cup molding machine, and the flange portion was further molded. The width of the flange portion is 3.5 mm. The presence or absence of a step in the flange portion was examined, and a lid member was sealed to the flange portion under a certain sealing condition, and the presence or absence of a leak was examined.
Cover material sealing conditions: seal temperature 200 ° C., seal load 392 N, seal time 0.5 seconds No leak: ○, leak: ×, slight leak: Δ

From the results in Table 1, the length (B) of the side overlapping the side edge (21b) which is the inner side of the more preferable container of the triangular resin part is 50% to 110% of the flange part width (W). I understood. According to the present invention, the level difference of the flange portion can be reduced, and a paper container without leak can be stably supplied.

DESCRIPTION OF SYMBOLS 1 ... Cup type paper container 2 ... Paper layer 2w ... Base paper web 3a ... Thermoplastic resin layer (outside)
3b ... thermoplastic resin layer (inside)
3c: Extruding portion 3d of the thermoplastic resin layer ... Folded thermoplastic resin layer 4 ... Gas barrier layer 5 ... Deformed long window 10 ... Lid 20 ... Trunk portion 20b ... Body part forming blank 20c ... Body part forming blank punching shape 21a ... Outer side edge 21b ... Inside side edge 21c ... Body part bonding part 22 ... Lower end Part 22a ... Lower folded part 22b ... Lower end winding part 23 ... Upper end part 23a ... Flange part outer edge 23b ... Flange part inner edge 23c ... Flange part inner layer 23d ... Flange part Bottom outer layer 23e ... Flange top outer layer 24 ... Steps 25a, 25b ... Corner cut part 26 ... Triangular resin part 30 ... Bottom part 30b ... Bottom part forming blank 31 ... Peripheral part BS ... Bottom sleeve FL Overlapping with ... flange portion W · · · width theta · · · triangular resin portion of the flange angle A · · · inwardly to become the side edges of the container length B · · · triangle resin portion of the hypotenuse of the triangle resin portion Side length

Claims (6)

A cylindrical body portion formed from a laminate having a paper layer and a thermoplastic resin layer provided on both sides of the paper layer; a bottom surface portion for sealing an opening below the body portion; and an upper portion of the body portion A cup-shaped paper container provided with a lid that seals the opening of
The body part is formed by rolling the upper end part of the body part one or more times outside and then flatly crushing the body part laminating part where both side edges of the body part forming blank are overlapped and sealed. Having a flanged portion,
The upper part of the left and right side edges of the body part forming blank has a corner cut part cut out in a triangle, and the side part edge on the inside of the container in the body part bonding part, from the paper layer The extended thermoplastic resin layer is folded outward, and in the corner cut part at the top of the side edge, there is no paper layer at the intersection of the side edge and the corner cut part. A triangular resin part consisting only of a resin layer is formed ,
The triangle the length of the resin portion overlapping the inner become side edges of the container side (B) is a cup paper container, characterized in der Rukoto 50% to 110% or less of the flange portion of the width (W). The bottom surface portion has a peripheral portion that is bent downward, and the peripheral portion of the bottom surface portion is inserted into a lower folded portion formed by folding the lower end portion of the trunk portion inwardly, and a lower end of the body portion, the cup paper container according to claim 1, characterized in that the peripheral portion of the bottom portion to form a bottom sleeve in close contact seal. The lower end portion of the body portion is folded inward to form a lower folded portion, and further folded toward the peripheral portion of the bottom surface portion to be tightly sealed to form a bottom sleeve. 2. The cup type paper container according to 2. The cup-shaped paper container according to claim 1, wherein a bottom portion is formed by folding a lower portion of a blank forming the body portion. In the said trunk | drum bonding part, the side edge used as the outer side of the container of the trunk | drum for blank formation is covered with the said thermoplastic resin layer, The any one of Claims 1-4 characterized by the above-mentioned. The cup-shaped paper container described. The cup-shaped paper container according to any one of claims 1 to 5 , wherein the thermoplastic resin layer on the inner surface side of the container includes a gas barrier layer.

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