JP4580500B2 - Square paper cup - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a square paper cup, and more particularly to a square paper cup with a reinforced top curl portion.
[0002]
[Prior art]
In the square paper cup, the top curl part is not particularly reinforced, so if you hold the square paper cup by hand when using it, it will be deformed, or the top curl part will be deformed, There is a risk that the overcap, which is the lid of the pattern paper cup, cannot be fitted, and when the square shape paper cup is held from the top of the overcap, the square shape paper cup may fall due to deformation of the square shape paper cup. There was a problem of having.
[0003]
Conventionally, as a method of strengthening the top curl part of this square paper cup, the basis weight of the base paper to be used is increased, the thickness of the paper is increased, or the material is bonded to reinforce the plastic film. A method of strengthening, a method of crushing and strengthening the top curl portion using heat, ultrasonic waves, etc., a so-called flange press, and a method of joining another plastic molded product to the top curl portion or the uncurled top portion. is there.
[0004]
[Problems to be solved by the invention]
However, in the method of strengthening the material surface by increasing the basis weight of the base paper to be used, which is a method of reinforcing the top curl portion, increasing the thickness of the paper, or bonding to reinforce a plastic film, The mechanical suitability at the time of molding the square paper cup is deteriorated, and at the same time, the cost is increased. In addition, the effect of a normal flange press, which is a method of forming a flange part by crushing and strengthening the top curl part using heat, ultrasonic waves, etc., is not significant, and a small square paper cup has practical problems. Although the strength of the top curl portion is not so great, the strength is insufficient in a large square paper cup or a square paper cup for heavy contents. Furthermore, the method of joining another plastic molded product to the top curled portion or the non-curled top portion has a problem from the viewpoint of environmental measures in which the amount of plastic products needs to be reduced as much as possible.
[0005]
On the other hand, the present invention solves the above-mentioned problem of the conventional square paper cup, and forms a top curl portion at the opening end by providing a notch in the corner portion of the blank constituting the body portion. This is a square paper cup formed by molding a blank of the body part with a wider width of the top curl entrainment part that becomes a straight part, and there is no problem in the molding process of the square paper cup. It is greatly strengthened as a flange part over the entire circumference including the top curl part which becomes a straight part in the processing process of a general flange press, which is a method of forming a flange part by crushing and strengthening using sound waves etc. The present invention provides a square paper cup that is not easily deformed.
[0006]
[Means for Solving the Problems]
The present invention has been studied to solve the above problems, and as a result, a corner blank and a bottom blank are molded, the corner of the rectangular opening is rounded, and the corner having the flange at the opening end is formed. a paper cup, the barrel blank, the top curl anchoring portions serving as the angle of the opening, the upper side partially provided notch taken arcuately, the straight portion of the opening In the portion, the top side is shaped to be a top curl entrainment portion having a width wider than that of the straight portion, and the flange is formed by forming a top curl portion at the opening end, and then subjected to flange press processing. The present inventors have found and completed a square paper cup characterized in that it is formed in a cross-sectional shape that is tripled over the entire circumference.
[0007]
According to the present invention, there is no problem in the forming process of the square paper cup, and the straight curl portion is formed in a general flange press processing step, which is a method of crushing and strengthening the top curl portion using heat, ultrasonic waves, or the like. It is possible to obtain a square paper cup that is greatly strengthened as a flange portion over the entire circumference including the top curl portion of the portion, and hardly deforms as a whole.
[0008]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, the present invention will be described in more detail with reference to the drawings.
[0009]
FIG. 1 is a perspective view and a cross-sectional view showing a state before a flange press working of a square paper cup 1 which is an example of an embodiment of the present invention, and a corner of a rectangular opening is rounded. A square paper cup 1 ′, which is composed of a body portion 2 and a bottom portion 3. The upper end of the body portion 2 is curled outward to form a top curl portion 4, and the lower end is curled inward to form a bottom curl portion 5. ing. The top curl portion 4 includes a straight portion and a corner portion. Further, the body portion 2 and the bottom portion 3 are integrated with each other at the bottom curl portion 5.
[0010]
FIG. 2 is a perspective view and a cross-sectional view of a square paper cup 1 which is an example of an embodiment of the present invention, and a top curl portion of the square paper cup 1 in a state before the flange press processing shown in FIG. 4 is used as a flange portion 6 by performing flange pressing. By forming the flange portion 6, the shape of the opening of the square paper cup 1 can be reliably held, and an overcap that is a lid can be covered. In the square paper cup 1 of the present invention, a notch is provided at the upper end of the corner portion, and the width of the top curl winding portion of the straight portion is wider than the width of the top curl winding portion of the corner portion. By forming the top curl portion 4 from the set blank by forming a square paper cup and then forming the flange portion 6 by flange pressing, the flange portion 6 is strengthened over the entire circumference including the straight portion. The strength of the square paper cup 1 as a whole can be increased. In the present embodiment, an arc-shaped notch is provided at the upper end of the corner portion, but the shape of the notch may be triangular, quadrangular, trapezoidal, or the like.
[0011]
Further, the square paper cup 1 of the present invention is manufactured by molding a body blank 10 as shown in FIG. 3 and a bottom blank 20 as shown in FIG. 4 with a square paper cup molding machine. Generally, the body blank 10 is punched in advance in the previous process, and the bottom blank 20 is punched on a square paper cup molding machine.
[0012]
Conventionally, as shown in FIG. 5, the top curl is designed to be top curled by a top curl winding portion A having the same width over the entire circumference of the opening of the square paper cup. In such a shape, in order to increase the strength of the top curl portion 4, it is possible to widen the top curl winding portion B over the entire circumference of the square paper cup and perform the top curl with a large amount of curling. It is very difficult to process cup molding. Accordingly, when the width of the top curl entrainment portion B suitable for general square paper cup molding is used, the cross-sectional shape of the flange portion subjected to double flange pressing as shown in FIG. 6A is obtained.
[0013]
On the other hand, the shape of the body blank 10 of the square paper cup 1 of the present invention is such that, as shown in FIG. 3, the top curl portion A <b> 2 that becomes the corner of the square paper cup 1 is partially cut off in an arc shape. Accordingly, in the portion that becomes the straight portion, the top curl winding portion A1 having a wider width than the portion that becomes the corner portion is formed. By adopting such a shape of the top curl winding portion B, in the square paper cup molding, the width of the top curl winding portion A1 of the portion that becomes the straight portion can be widened, and when the flange press processing is performed, a straight line is obtained. It becomes the cross-sectional shape of the flange part by which the flange press process was carried out in triple as shown in FIG. 6-b over the perimeter including the part used as a part and the part used as a corner | angular part. Thus, the strength of the entire square paper cup 1 can be increased by increasing the strength of the flange portion 6 having a triple cross-sectional shape by flange pressing the entire circumference of the top curl portion 4.
[0014]
The process for producing the square paper cup 1 using the trunk blank 10 and the bottom blank 20 will be briefly described. First, in order to bond the trunk blank 10 into a cylindrical shape, the cylinder blank 10 is bonded. Preheat the part with hot air to melt the resin on the surface. Next, the body blank 10 is wound around a body winding mold (mandrel), pressure-bonded, and bonded to a tubular body paper. In this step, the body blank 10 may be wound around a body winding mold (mandrel) and then heated and bonded with hot air. Subsequently, the body-wound paper is punched in advance and fitted into a mandrel on which a bottom blank 20 formed into a paper dish is placed, and at the same time, the resin at the bonding portion between the body-wound paper and the bottom blank 20 is preheated with hot air. Then, the lower end of the body wrapping paper is curled inward and pressure-bonded to form the bottom curled portion 5. Further, the upper end of the rolled paper is curled outward to form a top curl portion 4, and the square paper cup 1 before flange press processing is produced.
[0015]
Furthermore, the top curled portion 4 of the square paper cup 1 is crushed by flange press processing to form a reinforced flange portion 6. This flange pressing is performed using ultrasonic waves or heat sealing. In the case of using ultrasonic waves, the top curl portion 4 of the square paper cup 1 loaded in the mold is pressed by a horn 8 as shown in FIG. The top curl 4 of the square paper cup 1 received by the retainer 7 is sandwiched between the horn 8 and pressed and crushed. At the same time, the top curl 4 is self-heated by the ultrasonic wave oscillated from the horn 8 and the top is heated. In this method, the curled portion 4 is joined. In the case of heat sealing, it is a method of forming a flange portion in a paper cup molding machine by curling the top curl winding portion after precurling after blowing hot air and then pressing and crushing.
[0016]
Next, the composition of the material used for the square paper cup 1 of the present invention is based on the fact that paper is the main strength material and the innermost layer has a thermoplastic resin. The outermost layer is also preferably a thermoplastic resin. The innermost layer has a function of protecting the contents. On the other hand, in the outermost layer, in the flange press processing, the outermost layers are in close contact with each other to increase the strength of the flange portion. Examples of specific material configurations include paper / polyethylene, polyethylene / paper / polyethylene, polypropylene / paper / polypropylene, paper / polyethylene / aluminum / polyethylene, polyethylene / paper / polyethylene / aluminum / polyethylene, polyethylene / aluminum / paper / Examples include polyethylene.
[0017]
As the paper used as the main strength material, it is preferable to use a cup base paper having good suitability for forming a square paper cup. The basis weight is not particularly limited, but is more preferably in the range of 150 to 350 g / m ² in view of suitability for forming a square paper cup.
[0018]
The thermoplastic resin used in the innermost layer protects the contents, especially the function that does not leak even when liquid substances are added, and the function that enables the body part to be bonded together and the body part and the bottom part to be bonded by heat sealing It is necessary to have. Specific examples include polyethylene, polypropylene, polyester, and ethylene / vinyl acetate copolymer.
As thickness, the range of 15-60 micrometers is preferable.
[0019]
The thermoplastic resin used for the outermost layer needs to have a function that allows the outermost layers to be bonded by heat sealing. Specifically, polyethylene, polypropylene, polyester, ethylene / vinyl acetate copolymer, and the like can be used in the same manner as the thermoplastic resin used for the innermost layer. As thickness, the range of 15-60 micrometers is preferable. These thermoplastic resins are formed in the innermost layer and the outermost layer by extrusion processing or laminating processing.
[0020]
In the above embodiment, the case where the shape of the opening is rectangular has been described, but the opening may be a square with rounded corners. Furthermore, it is not limited to a rectangular square paper cup, but may be a polygonal square paper cup such as a triangular paper cup with round corners, a pentagonal paper cup, a hexagonal paper cup, or an octagonal paper cup.
[0021]
【Example】
Samples of examples of square paper cups according to the present invention were made according to the following specifications.
[0022]
[Example 1]
Specified shape of cup body; quadrangular pyramid content; 500 ml (full capacity)
Inner diameter of top curl; 88 x 61mm diameter (under neck)
Height: 115mm
Material: PE 20 μm / paper 300 g / m ² / PE 40 μm
Blank; shape shown in FIG.
[0023]
A square paper cup having the shape and material as described above was formed by molding with a paper cup molding machine. Then, in a paper cup molding machine, hot curling was blown after precurling the top curl entrained portion, curled, and then crimped and crushed to form a flange portion. In particular, the straight portion was strengthened, and it was difficult to cause deformation as a whole, and an excellent square paper cup could be produced from the viewpoint of environmental friendliness.
[0024]
【The invention's effect】
According to the present invention, a portion of the blank portion constituting the trunk portion is notched to form a top curl portion at the opening end, and the width of the top curl entrainment portion to be a straight portion is widened. This is a square paper cup formed by molding a blank, and there is no problem in forming a square paper cup by forming a blank of the body part with a wider width of the top curl entrainment part of the straight part. Furthermore, it is strengthened as a flange part over the entire circumference including the top curl part of the straight part in the processing process of a general flange press, which is a method of crushing and strengthening the top curl part using heat, ultrasonic waves, etc. As a whole, it is possible to obtain a square paper cup that is less likely to be deformed and that is favorable from the viewpoint of environmental friendliness.
[Brief description of the drawings]
FIG. 1 is a perspective view and a cross-sectional view showing a state before a flange press working of a square paper cup according to the present invention.
FIG. 2 is a perspective view and a sectional view showing a square paper cup according to the present invention.
FIG. 3 is a development view of a blank of a trunk portion of a square paper cup according to the present invention.
FIG. 4 is a development view of a blank at the bottom of a square paper cup according to the present invention.
FIG. 5 is a development view of a blank of a trunk portion of a conventional square paper cup.
FIG. 6 is a cross-sectional view of a top curl portion and a flange portion of a square paper cup according to the present invention.
FIG. 7 is a schematic view showing flange press working of a square paper cup according to the present invention.
[Explanation of symbols]
1 Square paper cup 1 'Square paper cup 2 Body 3 Bottom 4 Top curl 5 Bottom curl 6 Flange 7 Retainer (mold)
8 Horn A Top curl entrainment part (of the present invention)
A1 Top curl entrainment part (corner part of the present invention)
A2 Top curl entrainment part (straight line part of the present invention)
B Top curl entrainment part (conventional)
10 trunk blank 20 bottom blank

Claims (1)

A square paper cup that is molded with a body blank and a bottom blank, rounded at the corner of a square opening, and formed with a flange at the opening end,
In the top curl entrainment portion that becomes the corner portion of the opening portion , the trunk blank is provided with a notch obtained by partially cutting the upper side in an arc shape, and in the portion that becomes the straight portion of the opening portion , the upper side is a straight line a Jo shape were the top curl anchoring portions of wider width than the portion serving as the corner portion, and the flange is, after forming the top curl portion on the opening end, over the entire periphery by a flange pressing Mie Prefecture A square paper cup having a cross-sectional shape.

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