A foamed paper container

Abstract

This utility model discloses a foamed paper container, comprising: an inner paper tube with an open end and a closed end at its two ends, the inner diameter of the open end being larger than that of the closed end, and the open end gradually transitioning towards the closed end; a bottom cover, the outer edge of which is fixedly connected to the inner wall of the inner paper tube and spaced apart from the closed end; and a foamed paper sleeve, which is made of PE foamed paper, the inner wall of which has a gap fit with the outer edge of the inner paper tube before heat fusion and is fixedly connected after heat fusion, one end of the foamed paper sleeve being adjacent to the open end and the other end being adjacent to the bottom cover. In summary, this foamed paper container, through the gap fit between the foamed paper sleeve and the inner paper tube before heat fusion, facilitates the use of PE components to firmly connect the foamed paper sleeve and the inner paper tube during the heat fusion process, while simultaneously forming a heat-insulating microporous protrusion structure on the outer surface of the foamed paper sleeve, increasing the bonding strength to prevent delamination, increasing stiffness to prevent deformation under the pressure of the contents, improving the tactile feel, and ensuring heat insulation performance.

Description

Technical Field

[0001] This utility model relates to the field of foaming technology, and in particular to a foamed paper container. Background Technology

[0002] Foamed paper containers (typically represented by foamed paper cups and foamed paper tubes) are a type of composite packaging product that combines paper substrate with foam layer. The core feature is that it takes into account the environmental friendliness and processability of paper materials with the heat insulation and sealing properties of foam layer. They are widely used in hot beverage, fast food, baking and other scenarios.

[0003] In existing foamed paper containers, the core components of the container wall typically include a base layer and a foam layer. The base layer is mainly made of food-grade kraft paper or white cardboard, which provides structural support for the container and also has a certain degree of oil resistance and prevents the contents from penetrating. The foam layer is usually a PE (polyethylene) foam layer, which forms a porous structure through physical or chemical foaming, and can play a role in heat insulation, anti-scalding, and cushioning protection. The foam layer is mostly laminated on the outside of the base layer.

[0004] In addition, Chinese utility model patent with publication number CN202341587U discloses a paper cup insulation structure. The cup body is made of coated paper. The insulation effect is improved by the insulation gap formed after the insulation cup sleeve is combined with the cup body, and it has a better heat preservation effect.

[0005] However, in the aforementioned insulated paper cups, the presence of insulation gaps results in a small contact area between the insulation sleeve and the cup body, leading to poor bonding strength and the possibility of the sleeve detaching from the cup body. Furthermore, after the paper cup is filled with contents, the pressure from the contents causes the outer side of the sleeve to deform due to the lack of support from the insulation gaps, affecting the normal use of the paper cup. Moreover, the insulation gaps increase the overall thickness of the paper cup body and cause inconsistencies in the taper of the inner and outer walls, thus reducing the number of paper cups that can be stacked and increasing the space occupied for storage.

[0006] Therefore, it is necessary to improve the foamed paper containers in the existing technology. Utility Model Content

[0007] The purpose of this invention is to overcome the defects in the existing technology and provide a foamed paper container that increases bonding strength to prevent delamination, enhances stiffness to reduce deformation, and facilitates stacking and storage while ensuring heat insulation effect.

[0008] To achieve the above-mentioned technical effects, the technical solution of this utility model is: a foamed paper container, comprising: The inner paper tube has an open end and a closed end at both ends. The inner diameter of the open end is larger than the inner diameter of the closed end, and the open end gradually transitions to the closed end. The bottom cover has its outer circumferential edge fixedly connected to the inner circumferential wall of the inner paper tube and is spaced apart from the closed end. The foamed paper sleeve is a PE foamed paper sleeve. Its circumferential inner wall is in clearance fit with the circumferential outer edge of the inner paper tube before heat fusion and is fixedly connected after heat fusion. One end of the foamed paper sleeve is close to the opening end and the other end is close to the bottom cover.

[0009] Preferably, in order to increase the connection strength, the end of the foamed paper sleeve adjacent to the closed end has a first inwardly folded edge.

[0010] Preferably, to further prevent delamination, the inner paper tube includes a tube body, and a first outer folded edge is integrally connected to one end of the tube body adjacent to the open end. The tube body and the first outer folded edge form a closed-loop clamping groove, and one end of the foamed paper sleeve is clamped in the clamping groove.

[0011] Preferably, to facilitate the deformation of the outer fold, the cylinder body, the clamping groove, and the foamed paper sleeve are arranged to form a cavity.

[0012] Preferably, for ease of stacking and storage, the outer circumferential edge and the inner circumferential wall of the cylinder are both conical surfaces with coaxial centerlines.

[0013] Preferably, to further enhance the heat insulation performance, the inner paper tube is a foamed paper tube.

[0014] Preferably, for convenient stacking and storage, the circumferential outer edge of the foamed paper tube includes a foaming area and a heat insulation area arranged sequentially along the axial direction of the foamed paper tube and both being closed-loop. The foaming area is located between the closed end and the first inner folded edge, and the foamed paper sleeve covers the foaming area.

[0015] Preferably, in order to balance sealing performance, structural strength and manufacturing process, the distance between the bottom cover and the closed end is 5-15mm.

[0016] Preferably, in order to facilitate the holding of various contents, the foamed paper container is a foamed paper cup or a foamed paper bucket.

[0017] In summary, compared with the prior art, the foamed paper container of this utility model, through the gap fit between the foamed paper sleeve and the inner paper tube before hot melting, facilitates the use of PE components to firmly connect the foamed paper sleeve and the inner paper tube during the hot melting process. At the same time, it forms a heat-insulating microporous protrusion structure on the outer surface of the foamed paper sleeve, increasing the bonding strength to avoid delamination, while also increasing stiffness to avoid deformation due to the pressure of the contents, improving the feel, and ensuring heat insulation performance. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of this utility model; Figure 2 This is an exploded view of the present invention; Figure 3 This is an exploded view of the present invention from another perspective; Figure 4 This is a cross-sectional structural diagram of the present invention; Figure 5 yes Figure 4 Enlarged view of part A; Figure 6 yes Figure 4 Enlarged view of part B; In the diagram: 1. Inner paper tube; 11. Open end; 12. Closed end; 13. Tube body; 131. Foaming area; 132. Insulation area; 14. First outer fold; 15. Groove; 16. Cavity; 17. Second inner fold; 2. Bottom cover; 21. Base plate; 22. Lower fold; 3. Foamed paper sleeve; 31. First inner fold. Detailed Implementation

[0019] The specific embodiments of this utility model will be further described below with reference to the accompanying drawings and examples. The following examples are only used to more clearly illustrate the technical solution of this utility model and should not be construed as limiting the scope of protection of this utility model.

[0020] First Embodiment

[0021] like Figures 1-6 As shown, the foamed paper container of the first embodiment of this utility model includes: The inner paper tube 1 has an open end 11 and a closed end 12 at its two ends, respectively. The inner diameter of the open end 11 is larger than the inner diameter of the closed end 12, and the open end 11 is gradually transitioned to the closed end 12. The bottom cover 2 is fixedly connected to the circumferential inner wall of the inner paper tube 1 at its outer circumferential edge and is spaced from the closed end 12. Foamed paper sleeve 3, which is a PE foamed paper sleeve 3, has a gap fit between the inner wall and the outer edge of the inner paper tube 1 before heat fusion and is fixedly connected after heat fusion. One end of the foamed paper sleeve 3 is close to the opening end 11, and the other end is close to the bottom cover 2.

[0022] Specifically, in this embodiment, the foamed paper container is a foamed paper cup, which is convenient for holding contents, especially hot drinks such as coffee and milk tea. Of course, it can also be a foamed paper bucket, so as to hold other high-temperature contents, such as instant noodles.

[0023] The inner paper tube 1 forms the cup body of this embodiment, the bottom cover 2 forms the cup bottom of this embodiment, and the foamed paper sleeve 3 forms the heat insulation paper sleeve of this embodiment, thus ensuring the heat insulation performance of the foamed paper container of this embodiment.

[0024] Unlike existing technologies, in this embodiment, the inner paper tube 1 is pre-connected to the bottom cover 2 to form a paper container, i.e., a paper cup. Then, before heat melting, a foamed paper sleeve 3 is fitted over the inner paper tube 1, such that the inner circumferential wall of the foamed paper sleeve 3 is loosely fitted to the outer circumferential edge of the inner paper tube 1. Preferably, the inner circumferential wall of the foamed paper sleeve 3 is attached to the outer circumferential edge of the inner paper tube 1. Then, the paper cup is placed in an oven with the open end 11 facing down and the closed end 12 facing up. A heating device in the oven blows hot air downwards onto the paper cup, and this hot air acts on the foamed paper sleeve 3 outside the paper cup, causing it to foam. After being heated, the paper sleeve 3 foams, forming a foamed layer with a microporous raised structure on the outer surface. At the same time, the PE component inside the foamed paper sleeve 3 fills the gap between the foamed paper sleeve 3 and the inner paper tube 1. The PE component is used to firmly bond the foamed paper sleeve 3 and the inner paper tube 1, realizing the heat fusion connection between the foamed paper sleeve 3 and the inner paper tube 1. Since the foamed paper sleeve 3 and the inner paper tube 1 are fitted with a gap before heat fusion, it is beneficial for the PE component to fill between the foamed paper sleeve 3 and the inner paper tube 1, thereby increasing the contact area between the inner paper tube 1 and the foamed paper sleeve 3, thereby strengthening the connection strength between the two and preventing delamination after melting.

[0025] Furthermore, the PE material allows the foamed paper sleeve 3 to be integrated with the inner paper tube 1 to form a composite cup sleeve, thereby increasing the overall structural rigidity and preventing deformation caused by the pressure of the contents after filling, which could lead to spillage. In addition, after the foamed paper sleeve 3 is heated and foamed, a microporous raised structure is formed on the outermost layer of the paper cup, which improves the heat insulation performance and enhances the tactile feel, thus improving the user experience.

[0026] In order to form a paper cup before heat melting, in this embodiment, the bottom cover 2 includes a bottom plate 21 and a lower folded edge 22 integrally formed on the lower part of the bottom plate 21. The inner paper tube 1 includes a tube body 13 and a second inner folded edge 17. The second inner folded edge 17 is integrally formed on the side of the tube body 13 adjacent to the closed end 12. The second inner folded edge 17 is located inside the tube body 13 and forms an annular slot with the tube body 13. The lower folded edge 22 is sealed to the inner wall of the slot. Both the inner paper tube 1 and the bottom cover 2 are formed by processing PE composite paper. The PE composite paper includes a paper base layer and a PE layer that are stacked and connected. After the lower folded edge 22 is inserted into the slot, the tube body 13 and the lower folded edge 22 are heat-treated. The inner paper tube 1 and the bottom cover 2 are connected by the PE material between the inner paper tube 1 and the bottom cover 2, thereby realizing the fixed connection between the inner paper tube 1 and the bottom cover 2. The inner paper tube 1 and the bottom cover 2 form a paper cup.

[0027] A further improvement is that the distance between the bottom cover 2 and the closed end 12 is 5-15mm. Specifically, the distance between the bottom plate 21 and the closed end 12 is 10mm. This structure ensures sufficient contact area between the bottom cover 2 and the inner paper tube 1, forming a ring-shaped sealing strip through heat fusion, guaranteeing the seal between the bottom cover 2 and the inner paper tube 1. Furthermore, when the paper cup is filled with liquid, the bottom will bear a certain pressure. With this structure, a supporting edge is formed at the bottom of the cup, essentially adding a protective frame to the outside of the bottom cover 2, dispersing the pressure on the bottom of the paper cup, making the cup more stable, and preventing tilting caused by slight deformation of the bottom cover 2. In addition, paper cup production relies on automated equipment; a 10mm gap allows the mold to have sufficient workpiece to accommodate the folding mechanism, bending the originally straight cardboard into a structure where the bottom plate 21 and the lower folded edge 22 are integrally connected. Therefore, this design balances sealing performance, structural strength, and manufacturability.

[0028] A further improvement is that the end of the foamed paper sleeve 3 adjacent to the closed end 12 has a first inward folded edge 31.

[0029] This design helps to enhance the overall structural strength of the bottom of the foamed paper cup. In addition, it can also enhance the connection strength between the foamed paper sleeve 3 and the inner paper tube 1 after hot-melt bonding. The first inner folded edge 31 is used to connect with the inner paper tube 1, increasing the sealing between the foamed paper sleeve 3 and the inner paper tube 1 and preventing delamination.

[0030] A further improvement is that the cylinder body 13 is integrally connected to the end adjacent to the open end 11 with a first outer folded edge 14, and the cylinder body 13 and the first outer folded edge 14 form a closed-loop clamping groove 15, with one end of the foamed paper sleeve 3 clamped in the clamping groove 15.

[0031] A first outer fold 14 is provided at the end of the cylinder 13 adjacent to the open end 11 to form a clamping groove 15. Before heat melting, the foamed paper sleeve 3 is sleeved on the outside of the inner paper cylinder 1, and the end of the foamed paper sleeve 3 is inserted into the clamping groove 15. During the heating and foaming process, the foamed paper sleeve 3 expands due to heat, thereby clamping the end of the foamed paper sleeve 3 between the end of the cylinder 13 adjacent to the open end 11 and the first outer fold 14, which increases the connection strength between the inner paper cylinder 1 and the foamed paper sleeve 3 and prevents the foamed paper sleeve 3 from detaching from the inner paper cylinder 1.

[0032] A further improvement is that the cylinder body 13, the clamping groove 15, and the foamed paper sleeve 3 form a cavity 16. With this structure, when the clamping groove 15 clamps and fixes the end of the foamed paper sleeve 3, a certain deformation can be made to ensure that the foamed paper sleeve 3 is firmly clamped between the cylinder body 13 and the first outer folded edge 14.

[0033] A further improvement is that the curved surfaces of the outer circumferential edge and the inner circumferential wall of the cylinder 13 are both conical surfaces and have the same axis.

[0034] This structure facilitates the stacking and storage of the foamed paper cups.

[0035] Second Embodiment

[0036] As shown in the figure, the foamed paper container of the second embodiment of this utility model is based on the first embodiment, except that the inner paper tube 1 is a foamed paper tube and the outer edge of the circumference is a heat-insulating foamed surface.

[0037] After selecting foamed paper tubes for the inner paper tube 1, two foaming processes are performed during production. One foaming process involves blowing hot air onto the inner paper tube 1 and the foamed paper sleeve 3 from the outside of the foamed paper cup, causing the entire foamed paper sleeve 3 and the portion of the inner paper tube 1 not covered by the foamed paper sleeve 3 to foam. The other foaming process involves blowing hot air onto the circumferential inner wall of the paper cup from the inside, causing the portion of the inner paper tube 1 covered by the foamed paper sleeve 3 to foam. This increases the stiffness and heat insulation performance of the foamed paper cup, while also strengthening the connection structure between the inner paper tube 1 and the foamed paper sleeve 3, further reducing the gap between them, preventing them from separating, and thus ensuring the heat insulation, good feel, and structural strength of the foamed paper cup.

[0038] Third Embodiment

[0039] like Figure 4 As shown, the foamed paper container of the third embodiment of the present invention is based on the second embodiment, except that the circumferential outer edge of the foamed paper tube includes a foaming area 131 and a heat insulation area 132 arranged sequentially along the axial direction of the foamed paper tube and both being closed-loop. The foaming area 131 is located between the closed end 12 and the first inner folded edge 31, and the foamed paper sleeve 3 covers the foaming area 131.

[0040] Specifically, the foaming area 131 is a microporous protrusion area for surface heat insulation, and the heat insulation area 132 is an adhesive area covered by the foamed paper sleeve 3 with a smooth surface. The adhesive area is fixedly connected to the circumferential inner wall of the foamed paper sleeve 3.

[0041] With the above structure, the area of ​​the foamed paper sleeve 3 is divided into two parts. The part not covered by the foamed paper sleeve 3 is the foamed area 131, whose circumferential outer edge surface has a rough microporous protrusion structure, which has good heat insulation effect and structural rigidity. The other part is covered by the foamed paper sleeve 3, and its surface is fixedly connected to the foamed paper sleeve 3 without being foamed. During the production of this foamed paper cup, only the outer surface of the foamed paper cup needs to be heated, so that the area of ​​the inner paper tube 1 not covered by the foamed paper sleeve 3, that is, the foamed area 131 and the foamed paper sleeve 3, are heated and foamed together, while the heat insulation area 132 is covered by the foamed paper sleeve 3 and is not foamed.

[0042] In this way, the overall thickness of the foamed paper sleeve 3 is reduced, making it easier to stack and store. When hot drinks are poured in, the foaming area 131 foams after being heated by the hot drinks. Through foaming, the heat transferred to the foamed paper sleeve 3 is reduced, further ensuring the heat insulation performance. In addition, compared with the second embodiment, the foamed paper cup in this embodiment only needs to be foamed once to be formed. On the one hand, it is beneficial to reduce the process steps and thus improve production efficiency. On the other hand, there is no need to heat the inside of the paper cup, which reduces production costs.

[0043] The above description is only a preferred embodiment of the present utility model. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the technical principles of the present utility model, and these improvements and modifications should also be considered within the protection scope of the present utility model.

Claims

1. A foamed paper container, characterized in that, include: The inner paper tube has an open end and a closed end at both ends. The inner diameter of the open end is larger than the inner diameter of the closed end, and the open end gradually transitions to the closed end. The bottom cover has its outer circumferential edge fixedly connected to the inner circumferential wall of the inner paper tube and is spaced apart from the closed end. The foamed paper sleeve is a PE foamed paper sleeve. Its circumferential inner wall is in clearance fit with the circumferential outer edge of the inner paper tube before heat fusion and is fixedly connected after heat fusion. One end of the foamed paper sleeve is close to the opening end and the other end is close to the bottom cover.

2. The foamed paper container according to claim 1, characterized in that: The end of the foamed paper sleeve adjacent to the closed end has a first inward folded edge.

3. The foamed paper container according to claim 1, characterized in that: The inner paper tube includes a tube body, and a first outer folded edge is integrally connected to one end of the tube body adjacent to the open end. The tube body and the first outer folded edge form a closed-loop clamping groove, and one end of the foamed paper sleeve is clamped in the clamping groove.

4. The foamed paper container according to claim 3, characterized in that: The cylinder body, the clamping groove, and the foamed paper sleeve together form a cavity.

5. The foamed paper container according to claim 3, characterized in that: The outer circumferential edge and the inner circumferential wall of the cylinder are both conical surfaces with the same axis.

6. The foamed paper container according to claim 2, characterized in that: The inner paper tube is a foamed paper tube.

7. The foamed paper container according to claim 6, characterized in that: The outer circumferential edge of the foamed paper tube includes a foaming area and a heat insulation area arranged sequentially along the axial direction of the foamed paper tube and both being closed-loop. The foaming area is located between the closed end and the first inner folded edge, and the foamed paper sleeve covers the foaming area.

8. The foamed paper container according to any one of claims 1-7, characterized in that: The distance between the bottom cover and the closed end is 5-15mm.

9. The foamed paper container according to any one of claims 1-7, characterized in that: The foamed paper container is a foamed paper cup or a foamed paper bucket.

Images