JP2015101357A - Paper cup container and its manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper cup container in which the heating fitness in a heating plate type heating cabinet is superior, and burnt deposits are hard to be generated even if heated in a microwave oven, and also the separation of stacked empty containers is good, and further paper cracks are hard to be caused during manufacture, and to provide its manufacturing method.SOLUTION: A paper cup container is characterized as follows: a body part and a bottom part are formed of a laminate having thermoplastic layers on the most outer surface and the most inner surface of the container by mainly using a paper layer; the side edge serving as the inside of the container is covered so that the end face of the paper layer is not exposed in a body laminating part; the circumferential edge of the blank for forming a circular bottom part is folded downward in the bottom part; the lower end of the body part is rolled up inside so as to wrap the circumferential edge of the bottom part folded downward and is folded at a corner part and brought into close contact with the bottom face along with the circumferential edge of the bottom part, and thereby a flat leg part 22b is formed; and a ridge part 24 around the body part is formed in the corner upper part.

Description

  The present invention relates to a paper container for storing beverages and the like, and more particularly, to a cup-type paper container suitable for products that involve heating by a microwave oven, and products that are heated and sold in a hot-plate heating and storage cabinet, and a method for manufacturing the same. .

  As containers for storing food and beverages, containers of various shapes and various shapes are used. In recent years, containers using paper, which is a reproducible resource, have attracted particular attention against the background of increasing awareness of global environmental protection. Among them, the cup-shaped paper container is widely used as a container for storing various foods, beverages and the like in addition to the original paper cup use because of its ease of use and ease of manufacture.

  As a general shape of a cup-shaped paper container, as shown in FIGS. 14 (a) and 14 (b), a bottom part (200) and a bottom part (300), which are formed into a reverse tray shape ( The bottom sleeve (250) is generally formed by winding the lower end of the body (200) around the peripheral edge (310) of 300) and heat-pressing it. The upper end of the body part (200) is crushed after the roll forming to form a flange part (230), and a separately prepared lid member (not shown) is peelably sealed and sealed.

  Store beverages such as coffee in paper containers of this shape, put them in a hot-plate heating and storage cabinet commonly used in stores, etc., and compare them with products using metal cans Thus, there is a drawback that the rate of temperature rise is inferior. In addition to the cause of the low thermal conductivity of paper compared to metal, this is also due to the fact that the distance from the hot platen is far away because the bottom surface is raised and shaped like a bottom. .

  Moreover, when the contents are put in a cup-shaped paper container (100) as shown in FIG. 14 and heated in a microwave oven, the contents of the body part (200) are in direct contact with the contents, so the temperature exceeds 100 ° C. Although the bottom sleeve (250) is not in direct contact with the contents, it is heated to 100 ° C. or higher depending on the characteristics of the microwave oven, as shown in FIG. 14 (c). In some cases, a phenomenon of “burning” (400) occurs.

  This “burning” phenomenon is related to the characteristics of the microwave oven and the location in the microwave oven, and does not always occur. It was also the reason why it could not be actively used for microwave heating applications.

  The microwave oven paper cup described in Patent Document 1 is made to solve the above-mentioned problem of scoring, and as shown in FIG. 14 (d) in order to prevent the bottom sleeve from being formed. The bottom sleeve is formed by making the bottom surface (300) flat without being formed into a reverse tray shape, and the body (200) is not wound around the bottom surface (300), but is folded and crushed at 90 °. Is not formed.

  Since the microwave oven paper cup described in Patent Document 1 does not have a bottom sleeve, the bottom sleeve does not cause a scorching phenomenon. However, because of the structure, the end surface of the bottom portion contacts the contents, When used for frozen foods, moisture permeates from the end face, resulting in sanitary problems, and retort sterilization treatment cannot be performed after the contents are sealed.

The cup-type paper container described in Patent Document 2 which is the application of the applicant is made to solve this problem, and can be used for frozen foods. The present invention proposes a cup-type paper container that does not occur and can be sterilized by retort and a method for manufacturing the same.

  The cup-type paper container described in Patent Document 2 has a structure in which the end face of the paper layer is not exposed at all in both the laminating part and the bottom part of the trunk part, so there is no sanitary problem, and retort sterilization is also possible It is. Also, as shown in FIG. 9 (d), the bottom portion has a structure that does not have a bottom sleeve, so there is no problem of scorching at the time of heating a microwave oven, and it is also suitable for heating by a hot platen storage cabinet. Are better.

Japanese Patent No. 3953584 JP 2012-240695 A

  The cup-type paper container described in Patent Document 2 has no bottom sleeve on the bottom surface, has a flat bottom surface, and has a simple conical shape on the side surface. For this reason, when unfilled container bodies are stacked in the filling machine, as shown in FIG. 11, the container bodies are closely adhered to each other, and there is a problem that they are difficult to separate and difficult to separate. It was.

  Further, when the bottom surface portion is formed, the bottom sleeve that has been wound twice is further inwardly crimped, and thus the paper layer is greatly stretched at the corner portion of the bottom surface. For this reason, a paper break may occur at the corner.

  The problems to be solved by the present invention are excellent in heat aptitude in a hot-plate type storage, hardly burnt even when heated in a microwave oven, and the stacked empty containers are well separated. The present invention proposes a cup-type paper container that is less prone to paper breakage during production and a method for producing the same.

  As means for solving the above-mentioned problems, the invention according to claim 1 is a cup-type paper container comprising a cylindrical barrel portion and a bottom portion for sealing the lower portion of the barrel portion. The body part has a body part bonding part formed by overlapping and thermally fusing the left and right side edges of the body part forming blank, and the bottom part is a peripheral part of the bottom part forming blank. Is folded downward, and the lower end portion of the body portion is wound inside so as to wrap around the peripheral edge portion of the bottom surface portion bent downward, and is bent at the corner portion so as to adhere to the bottom surface together with the peripheral edge portion of the bottom surface portion. And it is a cup type paper container which comprises a flat leg part, and the above-mentioned corner part is formed with the convex strip part which goes around a trunk part.

  The cup-shaped paper container according to the present invention is formed with a protruding strip part that goes around the trunk part at the lower part of the trunk part, so that when empty containers are stacked, a space is created between the containers. Will be better. In addition, due to the action of the ridges, the elongation of the paper layer at the corners is reduced, and the paper layer is less likely to crack.

  The invention according to claim 2 is a cup-shaped paper container comprising a cylindrical barrel, a bottom portion for sealing the lower portion of the barrel, and a lid member for sealing the upper portion of the barrel. The body part and the bottom part are formed of a laminated body including a paper layer, and the laminated body is mainly composed of the paper layer and becomes the outermost surface of the container and the innermost surface of the container. The body part has a thermoplastic resin layer on the surface, and the body part is formed by stacking and thermally fusing the left and right side edges of the fan-shaped body part forming blank made of the laminate. In the body laminating portion, at least the side edge that is the inside of the container is covered so that the end surface of the paper layer is not exposed, and the upper end of the body is at least once outward. After being rolled up, it is crushed flat to form a flange part for bonding the lid, and the bottom part is The periphery of the circular bottom surface forming blank made of a body is bent downward, and the lower end of the body is wound inward so as to wrap around the periphery of the bottom surface bent downward, and is bent at the corner. In addition, together with the peripheral edge portion of the bottom surface portion, a flat leg portion is formed in close contact with the bottom surface, and a protruding strip portion that goes around the trunk portion is formed above the corner portion. It is a cup type paper container.

  The invention according to claim 3 is the cup-type paper container according to claim 2, wherein the laminate includes a gas barrier layer between the paper layer and the thermoplastic resin layer inside the container. is there.

  Moreover, invention of Claim 4 is a cup type paper container of any one of Claims 1-3 whose cross section of the said protruding item | line part is trapezoid shape, or is rectangular shape. is there.

  Moreover, invention of Claim 5 is a cup type paper container of any one of Claims 1-3 whose cross section of the said protruding item | line part is circular arc shape.

  The invention according to claim 6 is the method for manufacturing the cup-type paper container according to claim 4, wherein the lower end portion of the body portion is arranged so as to wrap around the peripheral portion of the bottom portion bent downward. A step of forming a flat leg portion in close contact with the peripheral edge portion of the bottom surface portion using the ultrasonic welder, and forming a flat leg portion using the ultrasonic welder. A gap of a certain width is provided between the ultrasonic horn of the portion including the outer peripheral portion of the leg portion and the cup receiving mold, and the height corresponding to the width of the gap is formed simultaneously with the molding of the leg portion. A method for producing a cup-shaped paper container, wherein the protruding line portion is formed.

  The invention according to claim 7 is the manufacturing method of the cup-type paper container according to claim 5, wherein the lower end portion of the body portion is arranged so as to wrap around the peripheral portion of the bottom portion bent downward. A step of forming a flat leg portion in close contact with the peripheral edge portion of the bottom surface portion using the ultrasonic welder, and forming a flat leg portion using the ultrasonic welder. The ultrasonic horn is provided with a curved gap extending outwardly in a portion including the outer peripheral portion of the leg, and simultaneously with the formation of the leg, the arc-shaped convex corresponding to the shape of the curved gap. It is a manufacturing method of a cup type paper container characterized by forming a section.

  In the cup-type paper container according to the present invention, the bottom structure is a structure in which the lower end portion of the body portion is wound inward and then tightly sealed, so that the bottom surface is flat and there is no bottom sleeve. For this reason, the heating aptitude in a hot-plate type hot storage is good. In addition, there is no burning when heated in a microwave oven.

  Also, the end face of the paper layer with which the contents touch is covered or entrained, and the end face of the paper layer is not exposed inside the container. It does not penetrate the layer. Therefore, it can be set as the package which has preservability.

  In addition, since the body portion and the bottom portion include a paper layer, there is an insulating property, and therefore, there is an advantage that a hand is not hot in handling during heating as compared with a metal can or a glass bottle.

  Since the cup-shaped paper container according to the present invention is provided with the protruding line part that goes around the body part, when the empty containers are stacked, the container main bodies are not in close contact with each other, and the separation is good.

  Further, by providing this ridge portion, the margin of extension of the paper layer at the corner portion in the process of folding the leg portion into the bottom surface and closely contacting it is eased, and the paper layer at the corner portion is less likely to crack.

  When the laminated body including the gas barrier layer is used as in the invention described in claim 3, a paper container capable of further long-term storage can be obtained. Further, when the end faces of all the paper layers are covered, a paper container that can be frozen and sterilized by retort can be obtained. Therefore, a cooking method in which the frozen and stored package is heated with hot water in a pan is also possible.

  According to the manufacturing method of the cup type paper container according to claim 6 or 7, compared with the conventional manufacturing method, between the cup receiving mold of the portion including the outer peripheral portion of the leg portion of the ultrasonic horn. Therefore, it is only necessary to change the gap, and there is no need to change the conventional manufacturing method or add a new process.

FIG. 1 is a perspective view showing an example of a cup-type paper container according to the present invention. FIG. 2A is a schematic cross-sectional view showing a vertical cross section of the cup-type paper container shown in FIG. 2B is a partially enlarged schematic cross-sectional view of the body portion in FIG. 2A, and FIG. 2C is a partially enlarged cross-sectional view of the bottom surface portion. FIG. 3A is a schematic cross-sectional view showing a horizontal cross section of the cup-type paper container shown in FIG. FIG.3 (b) is an expanded sectional schematic diagram of the trunk | drum bonding part in Fig.3 (a). FIG. 4 is a schematic plan view showing an example of a body portion forming blank and a bottom surface portion forming blank of the cup-type paper container according to the present invention. 5 (a), 5 (b), and 5 (c) are explanatory views showing an example of a method for producing a body forming blank of a cup-type paper container according to the present invention. 6 (a), 6 (b), and 6 (c) are cross-sectional explanatory views showing a process of forming the bottom surface of the cup-type paper container according to the present invention. FIG. 7 is an explanatory cross-sectional view showing a process of forming the bottom surface using an ultrasonic welder. FIG. 8 is a cross-sectional explanatory view showing a step of forming the bottom surface using an ultrasonic welding machine. FIGS. 9A, 9B and 9C are schematic cross-sectional views showing examples of the shape of the ridges in the cup-type paper container according to the present invention. FIG. 9D is a schematic cross-sectional view showing a similar part in a conventional cup-type paper container as a comparison. FIG. 10 is a schematic cross-sectional view showing a state in which the container main bodies of the cup-type paper containers according to the present invention are stacked. FIG. 11 is a schematic cross-sectional view showing a state in which container bodies of conventional cup-type paper containers are stacked. FIG. 12 is a schematic cross-sectional view showing another example of the layer structure of the laminate used in the cup-type paper container according to the present invention. FIG. 12A shows the layer configuration of the bottom portion, and FIG. 12B shows the layer configuration of the trunk portion. FIG. 13 is a graph showing the temperature rise characteristics of various containers in a hot platen warm storage. FIG. 14A is a perspective explanatory view showing the structure of a conventional cup-type paper container. FIG. 14B is a schematic partial sectional view of the paper container shown in FIG. FIG. 14C is a perspective view showing a state in which “burn” has occurred in the bottom sleeve portion. FIG. 14D is a schematic partial cross-sectional view of another conventional paper container.

  Hereinafter, a paper container and a manufacturing method thereof according to the present invention will be described in detail with reference to the drawings. The cup type paper container (1) according to the present invention is, in the example shown in FIGS. 1 and 2, a cup type paper container composed of a trunk portion (20), a bottom surface portion (30), and a lid member (10). And the trunk | drum (20) and the bottom face part (30) shape | mold the laminated body containing a paper layer (2).

  The laminate has a paper layer (2) as a main component and has a thermoplastic resin layer (3a) and a thermoplastic resin layer (3b) on at least the outermost surface of the container and the innermost surface of the container, respectively. .

  The body part (20) is formed by overlapping the left and right side edges (21a, 21b) of the sector-shaped body part forming blank (20b) made of the laminate as shown in FIG. 3, as shown in FIG. It becomes a cylindrical shape which has the trunk | drum bonding part (21c) formed by heat-seal | fusing.

  In this example, at least the side edge (21b) on the inner side of the container is not exposed to the end face (21e) of the paper layer, as shown in FIG. Covered with

  In the example of FIG. 3B, after the thermoplastic resin layers (3a, 3b) provided on the front and back surfaces of the paper layer (2) are bonded together, the end surface (21e) of the paper layer is folded back to the outside. Covered.

  FIGS. 5A, 5 </ b> B, and 5 </ b> C are explanatory views showing an example of a method for creating the body forming blank (20 b). First, as shown in FIG. 5 (a), the long window (6) was punched out while aligning with the web (2w) of the printed base paper, and then the thermoplastic resin layers (3a, 3b) were formed on the entire front and back surfaces. Provide. The portion of the long window (6) is in a state where the thermoplastic resin layers (3a, 3b) on the front and back surfaces are bonded to each other.

  Next, the body forming blank (20b) is punched out. At this time, as shown in FIG. 5 (b), the protruding portion of the thermoplastic resin layer on the side edge (21b) to be inside the container in the blank Punch out to leave (3c).

  Next, as shown in FIG. 5 (c), the protruding portion (3c) of the thermoplastic resin layer is folded and thermocompression bonded to the front side to form a folded thermoplastic resin layer (3h). The end face (21e) of the paper layer at the side edge (21b) of the forming blank (20b) is covered with the thermoplastic resin layer.

  As a method of covering the end face of the paper layer at the side edge, a method using an edge tape can be used in addition to this, and there is no particular limitation.

The upper end portion (23) of the trunk portion (20) is not particularly shown, but is finally wound once or more outside and then flatly crushed to bond the lid (10) to the flange portion ( 23f). Usually, it is often caught about once and a half.

  On the other hand, the bottom surface portion (30) is formed in a reverse tray shape by bending the peripheral edge portion (31) of the circular bottom surface portion forming blank (30b) made of the laminate, downward.

  As shown in FIG. 6A, the lower end portion (22) of the barrel portion (20) formed into a cylindrical shape was fitted into the outer periphery of the bottom surface portion (30) formed into a reverse tray shape. In the state, it is heated from the inside by a hot air heater (43).

  Next, as shown in FIG. 6 (b), the lower end portion (22) is wound inside so as to wrap around the peripheral edge portion (31) of the bottom surface portion bent downward, as shown in FIG. 6 (c). Next, it is bent at the corner portion (25) and is brought into close contact with the peripheral surface portion (31) of the bottom surface portion (30) to form a flat leg portion (22b).

  As shown in FIG. 6 (c), the cup-shaped paper container (1) according to the present invention has a ridge (24) formed around the body (20) above the corner (25). It is characterized by being.

  7 and 8 are cross-sectional explanatory views showing a process of forming the bottom surface using an ultrasonic welding machine. As shown in FIG. 7 (a), the container body (5) temporarily formed in the cup receiving mold (40) of the ultrasonic welder is set, and the ultrasonic horn (41) is used for pressure bonding from above. Apply sonic vibration.

  At this time, a gap (42) having a certain width is provided between the portion of the ultrasonic horn (41) including the outer peripheral portion of the leg portion (22b) and the cup receiving mold (40).

  By doing so, as shown in FIG. 7 (b), simultaneously with the formation of the leg portion (22b), the ridge portion (24) having a height corresponding to the width of the gap (42) is formed. The protrusion (24) formed by this method has a trapezoidal cross section as shown in FIG. 9 (a), or a protrusion having a rectangular cross section as shown in FIG. 9 (b). Part.

  As shown in FIG. 8 (a), when a curved gap (43) extending outward is provided in a part including the outer peripheral part of the leg part (22b) of the ultrasonic horn (41), Simultaneously with the formation of the portion (22b), an arc-shaped ridge (24) corresponding to the shape of the curved gap (43) is formed. The ridge (24) formed by this method is a ridge having an arcuate cross section as shown in FIG. 9 (c).

  In the cup-type paper container, when the empty containers are stacked due to the presence of the ridges (24) above the bottom corner part, a gap is generated between the containers as shown in FIG. When taking out one by one, you are well away.

  In the conventional cup-type paper container having no ridges as shown in FIG. 9D, the cup-type paper containers (100) are in close contact with each other as shown in FIG. If you are not well separated, it will cause a trouble when you take out the paper container from the stacked stack in the filling machine.

  In the cup type paper container (1) according to the present invention, the lower end portion (22) of the body portion (20) and the peripheral portion (31) of the bottom surface portion (30) are in close contact with the lower surface of the bottom surface portion (30). Sealed to form flat legs (22b).

  Thus, the cup-type paper container (1) according to the present invention has a flat bottom surface and does not have a bottom sleeve like a normal paper cup. For this reason, the temperature rising characteristic is good when heated in a hot-plate type storage, and no charring occurs when heated in a microwave oven.

  In addition, if the end surfaces of all paper layers are covered or protected by a thermoplastic resin layer, the end surfaces of the paper layers are not exposed inside or outside the paper container, so the contents are filled. The packaged body can be stored in a frozen state or a paper container that can be retort sterilized. Further, for example, a cooking method in which a frozen and stored package is heated with hot water in a pan is also possible.

  The cup-shaped container (1) according to the present invention has a heat insulating property because at least the body (20) and the bottom (30) include the paper layer (2), and therefore, when heated compared to a metal can. In handling, there are advantages such as not hot hands. There is also an advantage that the contents are difficult to cool.

  In spite of this advantage, the cup-type paper container according to the present invention is excellent in the heating temperature rise characteristic by the hot-plate type hot storage. This is presumably because the surface contacting the hot platen was crushed by the ultrasonic fusion machine, so that the heat insulation was reduced and the thermal conductivity was increased.

Moreover, since the basic shape of the cup-shaped paper container (1) according to the present invention is the same as that of a normal paper cup, it can be manufactured using a normal paper cup manufacturing apparatus.
However, when molding the legs (22b), it is necessary to heat and seal the four laminates at a time, so heat may be insufficient only by preheating with hot air normally used in the molding of paper cups. In addition to this, it is necessary to use a sealing method using ultrasonic waves in addition to this.

  In the body forming blank (20b) shown in FIG. 4, the corner portions are doubled by bonding the side edges to each other, and are folded back or rolled up to overlap each other. In order to avoid this, it is preferable to provide a notch in each corner in advance.

  FIG. 12 is a schematic cross-sectional view showing another example of the layer structure of the laminate used for the cup-shaped paper container (1) according to the present invention. As a laminate used for the cup-shaped paper container (1) according to the present invention, in addition to the thermoplastic resin layers (3a) and (3b) provided on the front and back surfaces of the paper layer (2), the paper layer (2) A gas barrier layer (4) may be provided between the inner surface side of the container and the thermoplastic resin layer (3b). The presence of the gas barrier layer (4) improves the storage stability after the container is filled with the contents. By appropriately selecting the material of the gas barrier layer (4), a product that can be stored at room temperature for a long time can be obtained.

  As a material of the gas barrier layer (4), it is preferable to use a material other than the metal foil, such as a gas barrier plastic film and an inorganic oxide vapor deposition film, on the premise of heating by a microwave oven.

The material used for the paper container according to the present invention will be described. The paper layer (2), other conventional cup base paper, white cardboard, coated cardboard, the basis weight of 160g ^{/ m 2} ~400g ^/ m 2 about paper ivory paper, etc. can be used.

As the thermoplastic resin layers (3a, 3b), polyolefin resins are generally used. Specifically, low density polyethylene, medium density polyethylene, linear low density polyethylene, ethylene / vinyl acetate copolymer, Ethylene resins such as ethylene / α-olefin copolymers and ethylene-methacrylic acid resin copolymers, blend resins of polyethylene and polybutene, homopolypropylene, propylene / ethylene random copolymers, propylene / ethylene block copolymers Polypropylene resins such as propylene / α-olefin copolymers are used.

  As a material used for the lid member (10), a laminated material in which several kinds of thermoplastic resin films are combined is used. Paper should be avoided for applications involving retort sterilization, as water will permeate when the edges are exposed. As a combination of thermoplastic resin films, for example, a transparent stretched film, a gas barrier film, and a sealant film can be combined.

  Examples of the transparent stretched film include film materials such as a polyester resin film such as polyethylene terephthalate (PET), a uniaxially stretched polypropylene resin film, a biaxially stretched polypropylene (OPP) resin film, and a biaxially stretched polyamide resin film. From the viewpoints of heat resistance, substrate strength, etc., a PET resin film can be preferably used.

  Examples of gas barrier films include polyvinylidene chloride films, polyvinyl alcohol films, ethylene vinyl alcohol copolymer films, gas barrier nylon films, gas barrier polyethylene terephthalate films, etc., PET films, etc., aluminum oxide, silicon oxide, etc. An inorganic oxide vapor-deposited film on which an inorganic oxide is deposited, or a polyvinylidene chloride coating, a film containing a water-soluble resin and an inorganic layered compound, or a film obtained by reacting a metal alkoxide or its hydrolyzate with an isocyanate compound. A gas barrier coating layer such as a resin layer can be used.

  The sealant film may be a single layer or multiple layers, but the innermost surface of the sealant layer is a low density polyethylene resin, a linear low density polyethylene resin, an ethylene-vinyl acetate copolymer resin, an ethylene-methacrylic acid copolymer resin. An easy peel sealant resin layer mainly composed of an acid copolymer resin such as an ethylene-acrylic acid copolymer resin is preferred. In any case, the material of these sealant layers is selected according to the material on the bonding surface side of at least the opening peripheral portion of the adherend container.

  Hereinafter, although the paper container concerning the present invention is explained based on an example, the paper container concerning the present invention is not limited to these.

After printing a pattern on the surface of a cup base paper having a basis weight of 260 g / m ² , as shown in FIG. 5, a long window was punched in accordance with the pattern, and low density polyethylene (LDPE) was used on the front and back surfaces using an extruder. ) Layer was formed. The thickness of the LDPE layer was 40 μm on the front side and 60 μm on the back side. This was punched out with a die, and the LDPE layer protruding from the side edge was folded back to protect the end face of the paper layer. A trunk portion forming blank and a bottom surface portion forming blank as shown in FIG. 4 were prepared.

  A bottom surface portion formed in a reverse tray shape was created from the bottom surface portion forming blank. On the other hand, a trunk forming blank was wound around the trunk forming mandrel to seal the trunk laminating portion and molded into a truncated cone. The body part and the bottom part are combined, and as shown in FIG. 6, after heating the adhesive part with a hot air heater, the lower end part of the body part is curled inward, and then an ultrasonic welder as shown in FIG. A flat leg was formed integrally with the bottom by heating with ultrasonic vibration while crushing the curl.

In FIG. 7, when the gap determined by the outer diameter dimension of the bottom surface of the container and the inner diameter of the ultrasonic horn was 0.5 mm, the finished height of the ridge was 0.3 mm. The width of the ridges was uneven due to the success. The cross-sectional shape of the ridge portion was a trapezoid with rounded corners as shown in FIG. Moreover, the height of the leg part was 2 mm. There was no paper breakage at the corner at the bottom of the trunk.

  As described above, a paper container body having a shape as shown in FIG. 1 was produced. At the time of molding, a hot air heater and an ultrasonic welding machine were used in combination, so there was no sealing failure and the sealing condition was good.

  The obtained cup-shaped paper container main body did not adhere to each other even when stacked, and was well separated.

  As the lid material, PET, 12 μm / stretched nylon, 25 μm / LDPE, and 30 μm were used without using paper. This was punched into a circle and prepared as a lid.

  The prepared container was filled with 200 ml of water, and the contents were heated using a hot plate type hot storage (Kanwarmer SW-126 manufactured by Nippon Heater Equipment Co., Ltd.). For comparison, the same volume of water is filled into a cup-shaped paper container of the same volume (bottom of the bottom sleeve 9 mm), steel can, and sheet-formed plastic cup (zero distance from the floor) molded by the conventional method. The contents were heated.

  The result is shown in FIG. As can be seen from this graph, the cup-type paper container according to the present invention has a greatly shortened heating time compared to the conventional cup-type paper container, and the heating rate is equal to or higher than that of steel cans and plastic cups. It turns out that it is.

  Moreover, even when heated in a microwave oven, there was no burning.

  The laminate was composed of LDPE, 60 μm / silica-deposited PET, 12 μm / LDPE, 17 μm / 260 g cup base paper / LDPE, 20 μm in order from the inside. A blank was created using this laminate, and a paper container having the structure shown in FIG. 9C was formed. In addition, as a lid | cover material, the thing of the structure of silica vapor deposition PET, 12 micrometers / stretched nylon, 25 micrometers / LDPE, 30 micrometers was used.

  The shape of the ultrasonic horn of the ultrasonic welder is a shape having a curved surface on the outside as shown in FIG. The finished shape of the ridges was the shape of FIG. 9C, and the height of the ridges was 0.3 mm and the width was 0.2 mm, which was almost uniform over the entire circumference.

  When the obtained cup-shaped paper container main body was filled with water and a heating test similar to that of Example 1 was performed, a similar temperature increase rate was obtained. Moreover, even if the container main body was stacked, the trunk portion was not in close contact, and separation was good. Moreover, even when heated in a microwave oven, there was no burning.

DESCRIPTION OF SYMBOLS 1 ... Cup type paper container 2 ... Paper layer 2w ... Base paper web 3a, 3b ... Thermoplastic resin layer 3c ... Extrusion part 3h of thermoplastic resin layer ... Folded thermoplastic resin Layer 4 ... Gas barrier layer 5 ... Container body 6 ... Long window 10 ... Lid 20 ... Body part 20b ... Body part forming part blanks 21a, 21b ... Side edge 21c: body part laminating part 21e: end face 22 of paper layer ... lower end part 22b ... leg part 23 ... upper end part 23f ... flange part 24 ... ridge part 25 ..Corner 30 ... Bottom 30b ... Bottom forming blank 31 ... Perimeter 40 ... Cup receiving mold 41 ... Ultrasonic horn 42 ... Gap 43 ... Curved surface Gap 44 ... Hot air heater 100 ... Cup-type paper container 200 ... Body 230 ... Nji 250 ... bottom sleeve 260 ... leg portion 300 ... bottom portion 310 ... circumferential edge portion 400 ... burnt

Claims (7)

A cup-type paper container comprising a cylindrical body and a bottom part for sealing the lower part of the body,
The body part has a body part bonding part formed by overlapping the left and right side edges of the body part forming blank and heat-sealing,
As for the bottom part, the peripheral part of the bottom part forming blank is bent downward,
The lower end portion of the body portion is wound inside so as to wrap around the peripheral edge portion of the bottom surface portion bent downward, is bent at the corner portion, and is closely attached to the bottom surface together with the peripheral edge portion of the bottom surface portion, so that a flat leg Part of
A cup-shaped paper container is characterized in that a convex strip portion that goes around the body portion is formed above the corner portion. A cup-shaped paper container comprising a cylindrical barrel, a bottom portion for sealing the lower portion of the barrel, and a lid member for sealing the upper portion of the barrel,
The body part and the bottom part are formed from a laminate including a paper layer,
The laminate is mainly composed of a paper layer and has a thermoplastic resin layer on the outermost surface of the container and on the outermost surface of the container,
The body part has a body part pasting part formed by overlapping the left and right side edges of the sector-shaped body part forming blank made of the laminate and heat-sealing,
In the body laminating portion, at least the side edge that is the inside of the container is covered so that the end face of the paper layer is not exposed,
The upper end of the trunk is wound once or more outside and then flattened to form a flange for bonding the lid.
As for the bottom surface, the peripheral edge of the circular bottom surface forming blank made of the laminate is bent downward,
The lower end portion of the body portion is wound inside so as to wrap around the peripheral edge portion of the bottom surface portion bent downward, is bent at the corner portion, and is closely attached to the bottom surface together with the peripheral edge portion of the bottom surface portion, so that a flat leg Forming part,
A cup-shaped paper container is characterized in that a convex strip portion that goes around the body portion is formed above the corner portion.   The cup-type paper container according to claim 2, wherein the laminate includes a gas barrier layer between the paper layer and the thermoplastic resin layer inside the container.   The cup-shaped paper container according to any one of claims 1 to 3, wherein the protruding portion has a trapezoidal cross section or a rectangular shape.   The cup-shaped paper container according to any one of claims 1 to 3, wherein the convex portion has a circular cross section. It is a manufacturing method of the cup type paper container according to claim 4,
The lower end portion of the body portion is wound inward so as to wrap around the peripheral portion of the bottom portion bent downward, bent at the corner portion, and together with the peripheral portion of the bottom portion on the bottom surface using an ultrasonic welding machine. Including the step of forming a flat leg,
In this step, a gap having a certain width is provided between the ultrasonic horn of the ultrasonic welder and the cup receiving mold of the portion including the outer peripheral portion of the leg portion,
A method for producing a cup-type paper container, wherein the convex strips having a height corresponding to the width of the gap are formed simultaneously with the formation of the leg portions. It is a manufacturing method of the cup type paper container according to claim 5,
The lower end portion of the body portion is wound inward so as to wrap around the peripheral portion of the bottom portion bent downward, bent at the corner portion, and together with the peripheral portion of the bottom portion on the bottom surface using an ultrasonic welding machine. Including the step of forming a flat leg,
In this step, the ultrasonic horn of the ultrasonic welder is provided with a curved gap extending outward in a portion including the outer peripheral portion of the leg portion,
A method of manufacturing a cup-type paper container, wherein the convex portion of the arc shape corresponding to the shape of the curved gap is formed simultaneously with the formation of the leg portion.

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