Foldable paper container
The paper container design with folding auxiliary lines and pressure indicators allows for easy folding with reduced force, addressing the challenge of space occupation and disposal efficiency.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- DAI NIPPON PRINTING CO LTD
- Filing Date
- 2024-12-20
- Publication Date
- 2026-07-02
Smart Images
Figure 2026109909000001_ABST
Abstract
Description
Technical Field
[0001] This invention relates to a collapsible paper container.
Background Art
[0002] Paper containers are sometimes used for packaging milk, fruit juice beverages, lactic acid bacteria beverages, noodle sauce, soup, sake, and other liquid foods. Paper containers have a lower environmental impact and are more sustainable than plastic containers.
[0003] When empty paper containers are discarded as they are without being crushed, they take up a lot of space, so they may be discarded after being crushed. In order to make paper containers easier to crush, Patent Document 1 discloses a paper container in which a longitudinal folding line for folding is formed on the side panel of the body, and first and second transverse folding lines for folding are formed respectively from the front panel of the body to the left and right side panels of the body.
Prior Art Documents
Patent Documents
[0004]
Patent Document 1
[0005] For the paper container of Patent Document 1, by pressing the front panel of the body, the longitudinal folding line for folding of the side panel of the body is valley-folded to overlap the front panel of the body and the back panel of the body, and then, by folding the upper and lower parts of the paper container along the first and second transverse folding lines for folding, the whole is flattened. In order to valley-fold the longitudinal folding line for folding of the side panel of the body so that the front panel of the body and the back panel of the body overlap, a certain amount of force is required.
Summary of the Invention
Problems to be Solved by the Invention
[0006] An object of this invention is to enable a paper container to be folded with a light force.
Means for Solving the Problems
[0007] The paper container according to the first invention is formed by folding a single blank sheet of paper into a box shape and bonding the pieces together, and comprises a rectangular cylindrical body having a front, back and left and right side panels, a top portion connected to the upper edge of the body and closing the top surface of the body, and a bottom portion connected to the lower edge of the body and closing the bottom surface of the body, wherein the left and right side panels of the body each have first and second vertical lines extending in the height direction (vertical direction) formed in the center in the width direction (horizontal direction), and the upper end of the first vertical line and the upper end of the second vertical line The panel is characterized by having an upper horizontal ruled line extending in the width direction at the point where the lines are connected, a lower horizontal ruled line extending in the width direction at the point where the lower end of the first vertical ruled line and the lower end of the second vertical ruled line are connected, and folding auxiliary ruled lines extending in the width direction between the upper horizontal ruled line and the lower horizontal ruled line, spaced apart from each of the upper and lower horizontal ruled lines, and having a pair of press indicators on at least one of the front panel and the back panel at a position that overlaps with the folding auxiliary ruled line and is close to each of the left and right side panels.
[0008] The paper container according to the first invention has the shape of a rectangular tube with the top and bottom closed by a top and bottom portion, respectively. The top portion may be a gable top type with inclined surfaces on the front and back sides, or it may be flat. A spout may be formed in part of the top portion, through which the contents can be poured out. The bottom portion is generally formed flat so that the paper container can stand upright. The paper container according to the first invention typically contains liquids, but powders or granules may be contained instead of liquids.
[0009] On each of the left and right side panels of the body, a first and second vertical line extending in the height direction is formed in the center in the width direction. Furthermore, an upper horizontal line extending in the width direction is formed at the position connecting the upper ends of the first and second vertical lines, and a lower horizontal line extending in the width direction is formed at the position connecting the lower ends. Therefore, after the front and back panels are stacked by folding the body along the first and second vertical lines, the top surface can be stacked on top of the body along the upper horizontal line, and the bottom surface can be stacked on top of the body along the lower horizontal line. The paper container folded along the first and second vertical lines and the upper and lower horizontal lines becomes flat and less bulky.
[0010] According to the first invention, in addition to the upper and lower horizontal lines, a folding auxiliary line is provided between the upper and lower horizontal lines, extending in the width direction at a distance from each of the upper and lower horizontal lines. A pair of pressure indicators are provided on at least one of the front panel and the back panel, at a position that overlaps with the folding auxiliary line and is close to the left and right side panels, respectively. When the pair of pressure indicators are pressed, a fold is first made along the folding auxiliary line, so that the front panel or back panel (the panel on which the folding auxiliary line is provided) that was initially pressed folds lightly (shallowly) inward along the folding auxiliary line. When the front panel or back panel folds lightly inward along the folding auxiliary line, light folds are made on the left and right side panels of the paper container along the first and second vertical lines. Next, the left and right side panels are firmly folded along the first and second vertical lines, so that the front and back panels overlap, and the body is folded. After that, the top and bottom sections are folded along the upper and lower horizontal lines.
[0011] According to the first invention, the folding of the body of the paper container, which is the trigger for folding, can be done with light force by indicating the folding auxiliary lines and the pressing points (pressure indicator). When the front panel or back panel is lightly folded inward along the folding auxiliary lines, light folds occur in the left and right side panels of the paper container along the first and second vertical lines, so that the subsequent firm folding of the left and right side panels along the first and second vertical lines can be smoothly achieved.
[0012] The paper container according to the second invention is formed by folding a single blank sheet of paper into a box shape and bonding the pieces together, and comprises a rectangular cylindrical body having a front, back and left and right side panels, a top surface connected to the upper edge of the body and closing the top surface of the body, and a bottom surface connected to the lower edge of the body and closing the bottom surface of the body, wherein the left and right side panels of the body each have first and second vertical lines extending in the height direction formed in the center in the width direction, and in the width direction at a position connecting the upper end of the first vertical line and the upper end of the second vertical line The panel is characterized by having an extending upper horizontal ruled line, a lower horizontal ruled line extending in the width direction at a position connecting the lower end of the first vertical ruled line and the lower end of the second vertical ruled line, a first folding auxiliary ruled line extending in the width direction between the upper horizontal ruled line and the lower horizontal ruled line, spaced apart from each of the upper and lower horizontal ruled lines, and a second diagonally extending folding auxiliary ruled line formed on each of the left and right side panels, with its vertex on the first folding auxiliary ruled line and forming an isosceles triangle with a part of the boundary ridge between the front panel and the left and right side panels as its base.
[0013] The paper container according to the third invention is formed by folding a single blank sheet of paper into a box shape and bonding the pieces together, and comprises a rectangular cylindrical body having a front, back and left and right side panels, a top surface connected to the upper edge of the body and closing the top surface of the body, and a bottom surface connected to the lower edge of the body and closing the bottom surface of the body, wherein the left and right side panels of the body each have first and second vertical lines extending in the height direction formed in the center in the width direction, and in the width direction at a position connecting the upper end of the first vertical line and the upper end of the second vertical line The panel is characterized by having an extending upper horizontal ruled line, a lower horizontal ruled line extending in the width direction at a position connecting the lower end of the first vertical ruled line and the lower end of the second vertical ruled line, a first folding auxiliary ruled line extending in the width direction between the upper horizontal ruled line and the lower horizontal ruled line, spaced apart from the upper horizontal ruled line and the lower horizontal ruled line, and a second diagonally extending folding auxiliary ruled line formed on each of the left and right side panels, with its vertex on the first folding auxiliary ruled line and forming an isosceles triangle with a part of the boundary ridge between the back panel and the left and right side panels as its base.
[0014] The second paper container according to the invention is characterized in that the base of the isosceles triangle is formed by a portion of the boundary ridge between the front panel and the left and right side panels, and the second folding auxiliary crease that forms the hypotenuse of the isosceles triangle is formed on the front panel side of the left and right side panels. The third paper container according to the invention is characterized in that the base of the isosceles triangle is formed by a portion of the boundary ridge between the back panel and the left and right side panels, and the second folding auxiliary crease that forms the hypotenuse of the isosceles triangle is formed on the back panel side of the left and right side panels.
[0015] According to the second and third inventions, a first folding auxiliary line is provided between the upper horizontal line and the lower horizontal line, extending in the width direction at a distance from each of the upper and lower horizontal lines, and a second folding auxiliary line is formed on the left and right side panels, extending diagonally and having its vertex on the first folding auxiliary line, and forming an isosceles triangle with a part of the boundary ridge between the front panel or back panel and the left and right side panels as its base.
[0016] The isosceles triangle has its base on the boundary ridge between the front / back panel and the left / right side panels, and its vertex lies on the first folding guideline. Therefore, when the front / back panel is pressed along the first folding guideline, the area near the base of the isosceles triangle on the left / right side panels is pressed. This causes a slight fold in the left / right side panels along the hypotenuse of the isosceles triangle (i.e., the second folding guideline). Following this slight fold along the hypotenuse of the isosceles triangle, the folding of the left / right side panels along the first and second vertical guidelines begins. Since the folding of the left / right side panels along the first and second vertical guidelines is assisted by the second folding guideline (the hypotenuse of the isosceles triangle), the paper container can be folded with less force.
[0017] Preferably, the vertex angle of the isosceles triangle is obtuse. When the first folding guide line on the front and back panels is pressed, a light fold along the hypotenuse (second folding guide line) of the isosceles triangle can be smoothly achieved. In one embodiment, the vertex angle is greater than 90 degrees and within the range of 130 degrees or less.
[0018] Preferably, the upper limit of the vertex angle is set to 120 degrees. This is to prevent the hypotenuse of the isosceles triangle from becoming unnecessarily long.
[0019] In other embodiments, the distance between the boundary ridge forming the base of the isosceles triangle and the vertex forming the vertex angle of the isosceles triangle is 5 mm or more. By securing a certain area of the isosceles triangle, it becomes easier to guide the left and right side panels along the hypotenuse (second folding auxiliary line) of the isosceles triangle. If the above distance is secured to 10 mm or more, the left and right side panels become even easier to guide.
[0020] In another embodiment, the distance between the boundary ridge forming the base of the isosceles triangle and the vertex forming the vertex angle of the isosceles triangle is between 1 / 4 and 1 / 2 of the width of the left and right side panels. Since a certain area of the isosceles triangle is secured, the force of the fingers pressing on the paper container can be transmitted efficiently.
Brief Description of the Drawings
[0021] [Figure 1] It is a development view of a gable top paper container of the first embodiment. [Figure 2] It is a perspective view of a gable top paper container of the first embodiment. [Figure 3] It is a front view of the gable top paper container of the first embodiment in the middle of folding. [Figure 4] It is a front view of the folded gable top paper container of the first embodiment. [Figure 5] It is a development view of a gable top paper container of the second embodiment. [Figure 6] It is a perspective view of a gable top paper container of the second embodiment. [Figure 7] It is a front view of the folded gable top paper container of the second embodiment. [Figure 8] It is a development view of a gable top paper container of another embodiment. [Figure 9] It is a development view of a gable top paper container of another embodiment.
Modes for Carrying Out the Invention
[0022] Hereinafter, an example of a paper container according to this invention will be described in detail with reference to the drawings.
Examples
[0023] Figures 1 to 4 show a gable top paper container of the first embodiment. Figure 1 shows a development view (blank 1A) of the paper container 1B, Figure 2 shows a perspective view of the paper container 1B, Figure 3 shows a front view showing the start of folding of the paper container 1B, and Figure 4 shows a front view showing the state where the paper container 1B is completely folded (indicated by the reference numeral 1C).
[0024] The blank 1A in Figure 1 shows the surface that will become the outer surface of the paper container 1B when assembled. It is formed by punching out a sheet mainly composed of paper (details of the sheet's layer structure will be described later) and adding creases (fold lines). As will be explained in detail below, the paper container 1B shown in Figure 2 is made by folding the blank 1A shown in Figure 1 along the creases and bonding or welding the parts together at the appropriate locations.
[0025] The lines formed on the blank 1A are broadly divided into two types: lines for assembling (shaping) a rectangular gable-top paper container 1B with a roof from the blank 1A, and lines for making the assembled paper container 1B easier to fold, as will be described later. The lines for assembling the paper container 1B are called "main lines" and are shown as solid lines in Figure 1. The lines for folding the paper container 1B to make it compact are called "folding auxiliary lines" and are shown as dashed lines in Figure 1.
[0026] Referring to Figure 1, the main lines and folding auxiliary lines are not formed continuously from one end to the other of the blank 1A, but rather have gaps in the lines at various points. This is to prevent the adhesion (welding) of the paper from being hindered by the main lines and folding auxiliary lines, or to prevent the folding from the blank 1A to the paper container 1B along the main lines from being hindered by the folding auxiliary lines. Depending on the material used for the blank 1A, there may be areas where the main lines or folding auxiliary lines are not formed, as shown in Figure 1, resulting in intermittent formation. Of course, the main lines and folding auxiliary lines may also be formed continuously without any intermittent sections.
[0027] First, we will explain the main lines and how to assemble a paper container using these lines.
[0028] Referring to Figure 1, Blank 1A has four main lines 61-64 that are spaced apart and run parallel to each other in a straight line in the vertical direction. These four vertical lines 61-64 divide Blank 1A into five sections (regions) arranged in a horizontal row. Of the five sections arranged in a horizontal row, the first four from the right form the basic structure of Paper Container 1B. The leftmost section is the section used for bonding or welding (glue area). Hereinafter, each of the five sections arranged horizontally will be collectively referred to as the 1st, 2nd, 3rd, 4th, and 5th panel bodies, from right to left. The 5th panel body will be specifically called the adhesive panel 15. The 1st to 4th panel bodies are approximately the same width, while the adhesive panel 15 is narrower than the width of the 1st to 4th panel bodies.
[0029] Each of the first to fourth panel bodies has a body panel portion 10 located in its vertical center, which constitutes the body of the paper container 1B formed by assembling a blank 1A. The roof panel portion 20, which constitutes the roof of the paper container 1B, is continuous with the upper end of the body panel portion 10, and the bottom panel portion 30, which constitutes the bottom surface of the paper container 1B, is continuous with the lower end of the body panel portion 10. The top seal portion 40 is further continuous with the upper end of the roof panel portion 20. A main crease line 51 extending in the width direction is formed at the boundary between the body panel portion 10 and the roof panel portion 20, a main crease line 52 extending in the width direction is formed at the boundary between the body panel portion 10 and the bottom panel portion 30, and a main crease line 53 extending in the width direction is formed at the boundary between the roof panel portion 20 and the top seal portion 40.
[0030] The body panel portions 10 of the first to fourth panel bodies constitute the rear panel 11, right side panel 12, front panel 13, and left side panel 14, respectively, when they are made into paper container 1B. The roof panel portions 20 of the first to fourth panel bodies constitute the rear roof panel 21, right folded roof panel 22, front roof panel 23, and left folded roof panel 24, respectively, when they are made into paper container 1B. The front roof panel 23 has a circular mounting hole H for attaching a spout C (see Figure 2). The top seal portions 40 of the first to fourth panel bodies constitute the rear seal panel 41, right folded seal panel 42, front seal panel 43, and left folded seal panel 44, respectively, when they are made into paper container 1B. The bottom panel portions 30 of the first to fourth panel bodies constitute the outer bottom panel 31, right folded bottom panel 32, inner bottom panel 33, and left folded bottom panel 34, respectively, when they are made into paper container 1B.
[0031] The right-side folding roof panel 22 and the left-side folding roof panel 24, which constitute the roof panel section 20, have main lines 55 and 56 formed on them, extending diagonally inward with a main line 51 extending in the width direction as the base, forming an isosceles triangle. The vertices of the isosceles triangles formed by the main lines 55 and 56 are located on the main line 53 extending in the width direction. The main lines 55 and 56, including the portion extending upward from the vertices of the isosceles triangles, are also formed on the right-side folding seal panels 42 and 44, which are connected to the upper ends of the right-side and left-side folding roof panels 22 and 24.
[0032] The right-side folding bottom panel 32 and the left-side folding bottom panel 34, which constitute the bottom panel portion 30, have main lines 57 and 58 formed on them, extending diagonally inward with a main line 52 that extends in the width direction as the base, forming an isosceles triangle. The vertices of the isosceles triangles formed by the main lines 57 and 58 do not reach the end faces of the right and left folding bottom panels 32 and 34, but are partway to the end faces. The main lines 57 and 58 include portions that extend downward from the vertices of the isosceles triangles and reach the end faces of the right and left folding bottom panels 32 and 34.
[0033] Main lines 54 extending in the width direction are formed on the right-side folding bottom panel 32 and the left-side folding bottom panel 34, which constitute the bottom panel portion 30, connecting the vertices of isosceles triangles formed by main lines 57 and 58, and extending from the right-side folding bottom panel 32 through the inner bottom panel 33 to the left-side folding bottom panel 34.
[0034] The assembly of the blank 1A into the paper container 1B is carried out as follows.
[0035] First, the blank 1A is folded along the main lines 61 and 63 extending in the height direction to make it flat, and the outer surface of the adhesive panel 15 (the fifth panel) is bonded to the inner surface of the first panel. This creates a flat, folded cylindrical body. The main lines 61 to 64 extending in the height direction that connect the first to fifth panel bodies are used to unfold the flat, folded cylindrical body, forming a rectangular tube with openings at the top and bottom.
[0036] Next, the base is formed. Specifically, the base panel portion 30, which is connected to the body panel portion 10 via the main crease line 52 extending in the width direction, is folded inward at a right angle relative to the body panel portion 10. At this time, in the right and left folded base panels 32 and 34, the outer area of the isosceles triangle (the area indicated by reference numerals 32A, 32B and 32C, and reference numerals 34A, 34B, and 34C) is folded outward along the main crease lines 57 and 58. Furthermore, when the outer base panel 31 is superimposed on the inner base panel 33, the leading edge portion of the inner base panel 33 (the area indicated by reference numeral 35) is folded inward along the main crease line 54 and superimposed on the inner base panel 33. The overlapping portions are glued together to form a flat base portion that is approximately square when viewed from the bottom.
[0037] After fixing the plug C into the mounting hole H, the contents are filled in from the upper opening. Then, the process proceeds to form the roof section.
[0038] The roof panel section 20 is folded inward along the main crease line 51 relative to the body panel section 10. The right and left folded roof panels 22 and 24 are folded inward along the main crease lines 55 and 56, with the outer area of the isosceles triangle (indicated by symbols 22A, 22B, 24A, and 24B) being valley-folded. The right and left folded seal panels 42 and 44 of the top seal section 40 are folded in half along the main crease lines 55 and 56. The overlapping parts are glued together to form the roof section. The gable-top paper container 1B is completed (Figure 2).
[0039] Next, we will explain the folding guide lines and how to fold paper container 1B using these guide lines.
[0040] The folding auxiliary lines are all formed on the body panel portion 10 (see the dashed line in Figure 1), and consist of three horizontal auxiliary lines 71, 72, and 73 that are spaced apart vertically and extend parallel to each other in the width (horizontal) direction, vertical auxiliary lines 81 and 82 that extend in the height direction on the right and left side panels 12 and 14, and a triangular auxiliary line 91 on the right side panel 12 that has its vertex at the top of the vertical auxiliary line 81 and forms two sides of an isosceles triangle with the main line 51 as its base, and left The side panel 14 includes a triangular auxiliary line 92 whose vertex is at the upper end of the vertical auxiliary line 82 and forms two sides of an isosceles triangle with the main line 51 as its base; a triangular auxiliary line 93 whose vertex is at the lower end of the vertical auxiliary line 81 and forms two sides of an isosceles triangle with the main line 52 as its base on the right side panel 12; and a triangular auxiliary line 94 whose vertex is at the lower end of the vertical auxiliary line 82 and forms two sides of an isosceles triangle with the main line 52 as its base on the left side panel 14. The vertical auxiliary lines 81 and 82 on the right and left side panels 12 and 14 are formed at positions that divide the width of the right and left side panels 12 and 14 in half.
[0041] The three horizontal auxiliary lines 71, 72, and 73, which extend in the width direction, each have a different function.
[0042] The uppermost horizontal auxiliary crease 71 is for folding the roof panel portion 20 and top seal portion 40 of the paper container 1B toward the front panel 13 or rear panel 11, and is formed to be in contact with the upper ends of the vertical auxiliary creases 81 and 82 of the right and left side panels 12 and 14. Hereinafter, the horizontal auxiliary crease 71 will also be referred to as the "top folding auxiliary crease 71". The top folding auxiliary crease 71 extends parallel to the main crease 51 and is formed at a distance equal to, for example, half the width of the right and left side panels 12 and 14.
[0043] The lowest horizontal auxiliary line 73 is for folding the bottom panel portion 30 of the paper container 1B toward the front panel 13 or the back panel 11, and is formed to be in contact with the lower ends of the vertical auxiliary lines 81 and 82 of the right and left side panels 12 and 14. Hereinafter, the horizontal auxiliary line 73 will also be called the "bottom folding auxiliary line 73". The bottom folding auxiliary line 73 extends parallel to the main line 52 and is formed at a distance equal to, for example, half the width of the right and left side panels 12 and 14.
[0044] A horizontal auxiliary line 72 is located between the top folding auxiliary line 71 and the bottom folding auxiliary line 73. The horizontal auxiliary line 72 is formed to facilitate the mountain fold (assist in mountain folding) of the right and left side panels 12 and 14 along the vertical auxiliary lines 81 and 82 when the front panel 13 or back panel 11 is initially pressed to fold the paper container 1B. Hereinafter, the horizontal auxiliary line 72 will also be referred to as the "folding start auxiliary line 72". The folding start auxiliary line 72 is located, for example, exactly halfway between the top folding auxiliary line 71 and the bottom folding auxiliary line 73.
[0045] A pair of pressure indicator sections 13A are printed on the folding start auxiliary line 72 of the front panel 13, near the right side and left side panels 12 and 14, respectively. The pressure indicator sections 13A are printed with characters (in this embodiment, "press"), symbols, codes, etc., that clearly indicate the area (range) to be pressed. Stickers may be affixed instead of printing.
[0046] The paper container 1B is folded as follows:
[0047] Referring to Figure 3, first, a pair of pressure indicator sections 13A on the front panel 13 are pressed. The pair of pressure indicator sections 13A are located on the widthwise-extending folding start auxiliary lines 72 formed on the front panel 13, and are close to the left and right side panels 12 and 14, respectively. When the pair of pressure indicator sections 13A are pressed, for example, if grasped with both thumbs, force is applied to the boundary ridges (main lines 62 and 63) between the front panel 13 and the left and right side panels 12 and 14. The front panel 13 bends along the folding start auxiliary lines 72, and a recess is created in the front panel 13.
[0048] A dent (bending along the folding start guideline 72) occurs in the front panel 13, causing the right and left side panels 12 and 14 to bulge outwards. Since vertical guidelines 81 and 82 are formed on the right and left side panels 12 and 14, when the right and left side panels 12 and 14 bulge outwards, bending occurs along the vertical guidelines 81 and 82 on the right and left side panels 12 and 14.
[0049] Referring to Figure 4, when the front panel 13 is pressed across its entire surface, the front panel 13 overlaps with the back panel 11, and the right and left side panels 12 and 14 are folded in half along the vertical auxiliary lines 81 and 82. When the front panel 13 overlaps with the back panel 11, the top of the front panel 13 is valley-folded towards the front panel 13 along the top folding auxiliary line 71 that extends in the width direction, and the bottom of the front panel 13 is valley-folded towards the front panel 13 along the bottom folding auxiliary line 73 that extends in the width direction. At the top of the front panel 13, the roof panel portion 20 and the top seal portion 40 overlap the top of the front panel 13 along the auxiliary lines 91 and 92. At the bottom of the front panel 13, the bottom panel portion 30 overlaps the bottom of the front panel 13 along the auxiliary lines 93 and 94. The entire paper container 1B is folded flat (see paper container 1C).
[0050] Instead of folding the paper container 1B from the front panel 13 side, the paper container 1B can also be folded from the rear panel 11 side. The roof panel portion 20 and the top seal portion 40 are superimposed on the top of the rear panel 11, and the bottom panel portion 30 is superimposed on the bottom of the rear panel 11. A pair of press indicators 13A may also be printed on the rear panel 11 in addition to or instead of the front panel 13. [Examples]
[0051] Figures 5 to 7 show the gable-top paper container of the second embodiment. Figure 5 shows the unfolded view (blank 2A) of the paper container 2B of the second embodiment, Figure 6 shows a perspective view of the assembled paper container 2B, and Figure 7 shows a front view of the paper container 2B in a completely folded state (indicated by reference numeral 2C).
[0052] The paper container of the second embodiment differs from the paper container of the first embodiment in that auxiliary lines 95-98 are added to the left and right side panels 12 and 14. Parts identical to those of the paper container of the first embodiment are given the same reference numerals, and redundant explanations are omitted.
[0053] The four auxiliary lines 95-98 are all formed on the left and right side panels 12 and 14. Of the four auxiliary lines 95-98, auxiliary lines 96 and 97 are composed of lines that extend diagonally to form an isosceles triangle, with its vertex on the folding start auxiliary line 72 and its base being part of the boundary ridge between the front panel 13 and the left and right side panels 12 and 14 (main lines 62 and 63) (see Figures 5 and 6). As described above, the folding start auxiliary line 72 may be formed intermittently, and for this reason, strictly speaking, the vertex of the isosceles triangle may not be on the folding start auxiliary line 72, but even in that case, the vertex of the isosceles triangle is located on a straight line along the folding start auxiliary line 72. The auxiliary lines 95 and 98 are composed of lines that extend diagonally to form an isosceles triangle, with their vertices located on the folding start auxiliary line 72 and using a portion of the boundary ridge (main lines 61 and 64) between the back panel 11 and the left and right side panels 12 and 14 as their base. Hereinafter, auxiliary lines 95 to 98 will be referred to as "triangular auxiliary lines 95 to 98" due to their shape.
[0054] When the pair of pressure indicator sections 13A on the front panel 13 are pressed, force is applied to the boundary ridge (main lines 62, 63) between the front panel 13 and the left and right side panels 12, 14, causing the left and right side panels 12, 14 to bulge outward as described above. When the outward bulging of the left and right side panels 12, 14 begins, they are initially lightly folded along the triangular auxiliary lines 96, 97. Also, since both thumbs make broad contact within the isosceles triangle formed by the triangular auxiliary lines 96, 97, the pressure from the fingers can be efficiently transmitted to the paper container 2B. The paper container 2B can be folded with light force without any strain.
[0055] The paper container 2B can also be folded from the back. When pressure is applied to the area of the back panel 11 near the left and right side panels 12 and 14 on the folding start auxiliary rule line 72, force is applied to the boundary ridge (main rule lines 61 and 64) between the back panel 11 and the left and right side panels 12 and 14, causing the left and right side panels 12 and 14 to bulge outwards. As the outward bulging of the left and right side panels 12 and 14 begins, they are lightly folded inwards along the triangular auxiliary rule lines 95 and 98. The paper container 2B can be folded with light force.
[0056] In the paper container of the second embodiment, in addition to the pair of press indicators 13A located near the left and right side panels 12 and 14 on the folding start auxiliary line 72 of the front panel 13, a pair of press indicators ("press") 13A may also be printed on the back panel 11 near the left and right side panels 12 and 14 on the folding start auxiliary line 72.
[0057] Figures 8 and 9 show unfolded diagrams 3A and 4A of paper containers of other embodiments, respectively. Unfolded diagram 3A in Figure 8 differs from unfolded diagram 2A (Figure 5) of the paper container of the second embodiment in that the press indicator (the word "Osu") 13A is not printed on the front panel 13, and triangular auxiliary lines 95 and 98 of the four triangular auxiliary lines 95 to 98 are not formed on the left and right side panels 12 and 14. Unfolded diagram 4A in Figure 9 differs from unfolded diagram 2A (Figure 5) of the paper container of the second embodiment in that the press indicator (the word "Osu") 13A is not printed on the front panel 13, and triangular auxiliary lines 96 and 97 of the four triangular auxiliary lines 95 to 98 are not formed on the left and right side panels 12 and 14. The paper container assembled from unfolded diagram 3A in Figure 8 is folded from the front panel 13 side. The paper container assembled from the unfolded diagram 4A in Figure 9 is folded from the back panel 11 side.
[0058] Table 1 shows the measured force required for folding the paper container 1B of the first embodiment and the paper container 2B of the second embodiment, respectively, and indicates the measured force (in Newtons (N)) required until the front panel 13 and the back panel 11 overlap. For comparison, a paper container without the folding start guideline 72 (comparative example) was also created, and the force required for the comparative example until the front panel 13 and the back panel 11 overlapped was measured in the same manner.
[0059] [Table 1]
[0060] In the measurement test, for each of the paper container test specimens 1 to 5 (N=1 to N=5), the front panel 13 and the back panel 11 were overlapped by pressing a push-pull gauge against a point 2 mm from the boundary ridge between the front panel 13 and the left side panel 14, on the folding start auxiliary crease 72 of the front panel 13 (midway between the top folding auxiliary crease 71 and the bottom folding auxiliary crease 73 in the case of the comparative example paper container). Similarly, the front panel 13 and the back panel 11 were overlapped by pressing a push-pull gauge against a point 2 mm from the boundary ridge between the front panel 13 and the right side panel 12. Table 1 shows the measured values when the push-pull gauge was pressed against a point 2 mm from the boundary ridge between the front panel 13 and the left side panel 14 (left) and the measured values when the push-pull gauge was pressed against a point 2 mm from the boundary ridge between the front panel 13 and the right side panel 12 (right). Table 1 also shows the average values.
[0061] Compared to the comparative paper container without the folding start auxiliary line 72, the paper container 1B of the first embodiment, which has the folding start auxiliary line 72, and the paper container 2B of the second embodiment, which has the folding start auxiliary line 72 in addition to triangular auxiliary lines 95-98, were found to be able to be folded with less force. Furthermore, the paper container 2B of the second embodiment could be folded with even less force than the paper container 1B of the first embodiment, although only slightly, confirming the effect of forming the triangular auxiliary lines 95-98.
[0062] The triangular auxiliary lines 95-98 are formed such that the vertex angle α (see Figure 5) of the isosceles triangle formed by these lines is obtuse, specifically between 90 and 130 degrees. This reduces the base angles of the isosceles triangle, allowing for a smooth transition when folding the paper container B from a light mountain fold of the left and right side panels 12 and 14 along the triangular auxiliary lines 95-98 to a firm fold of the left and right side panels 12 and 14 along the vertical auxiliary lines 81 and 82. Preferably, the upper limit of the vertex angle α of the isosceles triangle is set to 120 degrees. This is to prevent the hypotenuse of the isosceles triangle from becoming unnecessarily long.
[0063] The height T of the isosceles triangle formed by the triangular auxiliary lines 95-98 (Figure 5 only shows the height T of the isosceles triangle formed by the triangular auxiliary line 96) should be 5 mm or more. This is because securing a certain area of the isosceles triangle makes it easier to guide the left and right side panels 12 and 14 along the triangular auxiliary lines 95-98 into a gentle mountain fold. If the height T is 10 mm or more, the gentle mountain fold of the left and right side panels 12 and 14 will be even easier to guide, and it will also be easier to firmly grip the isosceles triangle with your fingers.
[0064] Structurally, the height T of the isosceles triangle formed by the triangular auxiliary lines 95-98 (the distance between the boundary ridge constituting the base of the isosceles triangle and the vertex forming the vertex angle of the isosceles triangle) is preferably between 1 / 4 and 1 / 2 of the width of the left and right side panels 12 and 14, from the viewpoint of securing a certain area of the isosceles triangle.
[0065] The sheets used in paper containers 1B and 2B can have, for example, the following layer structure and layer thickness from the outside to the inside.
[0066] PE(25μm) / Paper(382g / m 2 ) / Barrier layer / PET (12μm) / PE (60μm)
[0067] PE stands for polyethylene, and PET stands for polyethylene terephthalate. Both materials have a layered structure that is primarily paper with PE laminated on the outermost surfaces of both the outer and inner surfaces, making them suitable for heat welding. [Explanation of symbols]
[0068] 1A,2A,3A,4A development view 1B,1C,2B,2C paper container 10. Torso panel section 11. Rear panel 12 Right side panel 13 Front Panel 13A Pressure Indicator 14. Left side panel 15 Adhesive Panels 20 Roof panel section 30 Bottom panel section 40 Top seal portion 51, 52, 53, 61, 62, 63, 64 Main grid lines 71. Folding guide lines on the top surface (horizontal lines at the top) 72 Folding start auxiliary line (folding auxiliary line, first folding auxiliary line) 73. Folding guide lines on the bottom (horizontal lines at the bottom) 81,82 Vertical auxiliary lines (1st and 2nd vertical lines) 95, 96, 97, 98 Triangular auxiliary lines (second folding auxiliary lines)
Claims
1. A paper container formed by folding a single blank sheet of paper into a box shape and gluing it together, comprising a rectangular cylindrical body with front, back and left and right side panels, a top portion connected to the upper edge of the body and closing the top surface of the body, and a bottom portion connected to the lower edge of the body and closing the bottom surface of the body, On each of the left and right side panels of the above-mentioned body, a first and second vertical line extending in the height direction is formed in the center in the width direction, An upper horizontal ruled line extending in the width direction at the position connecting the upper end of the first vertical ruled line and the upper end of the second vertical ruled line, A lower horizontal ruled line extending in the width direction at a position connecting the lower end of the first vertical ruled line and the lower end of the second vertical ruled line, and Between the upper horizontal rule and the lower horizontal rule, there is a folding auxiliary rule that extends in the width direction, spaced apart from the upper horizontal rule and the lower horizontal rule, A pair of pressure indicators is provided on at least one of the front panel and the rear panel, at a position that overlaps with the folding auxiliary lines and is close to the respective left and right side panels. Paper container.
2. A paper container formed by folding a single blank sheet of paper into a box shape and gluing it together, comprising a rectangular cylindrical body with front, back and left and right side panels, a top portion connected to the upper edge of the body and closing the top surface of the body, and a bottom portion connected to the lower edge of the body and closing the bottom surface of the body, On each of the left and right side panels of the above-mentioned body, a first and second vertical line extending in the height direction is formed in the center in the width direction, An upper horizontal ruled line extending in the width direction at the position connecting the upper end of the first vertical ruled line and the upper end of the second vertical ruled line, A lower horizontal ruled line extending in the width direction at the position connecting the lower end of the first vertical ruled line and the lower end of the second vertical ruled line, Between the upper horizontal rule and the lower horizontal rule, a first folding auxiliary rule extends in the width direction with a gap between it and each of the upper and lower horizontal rule, and Each of the left and right side panels has a second diagonally extending folding auxiliary line that has its vertex on the first folding auxiliary line and forms an isosceles triangle with a part of the boundary ridge between the front panel and the left and right side panels as its base. Paper container.
3. A paper container formed by folding a single blank sheet of paper into a box shape and gluing it together, comprising a rectangular cylindrical body with front, back and left and right side panels, a top portion connected to the upper edge of the body and closing the top surface of the body, and a bottom portion connected to the lower edge of the body and closing the bottom surface of the body, On each of the left and right side panels of the above-mentioned body, a first and second vertical line extending in the height direction is formed in the center in the width direction, An upper horizontal ruled line extending in the width direction at the position connecting the upper end of the first vertical ruled line and the upper end of the second vertical ruled line, A lower horizontal ruled line extending in the width direction at the position connecting the lower end of the first vertical ruled line and the lower end of the second vertical ruled line, Between the upper horizontal rule and the lower horizontal rule, a first folding auxiliary rule extends in the width direction with a gap between it and each of the upper and lower horizontal rule, and Each of the left and right side panels has a second diagonally extending folding auxiliary line that has its vertex on the first folding auxiliary line and forms an isosceles triangle with a part of the boundary ridge between the back panel and the left and right side panels as its base. Paper container.
4. The vertex angle of the above isosceles triangle is obtuse. The paper container according to claim 2 or 3.
5. The above vertex angle is greater than 90 degrees and within the range of 130 degrees or less. The paper container according to claim 4.
6. The distance between the boundary ridge forming the base of the above isosceles triangle and the vertex forming the vertex angle of the above isosceles triangle is 5 mm or more. The paper container according to claim 2 or 3.
7. The distance between the boundary ridge forming the base of the above isosceles triangle and the vertex forming the vertex angle of the above isosceles triangle is between 1 / 4 and 1 / 2 of the width of the above left and right side panels. The paper container according to claim 2 or 3.