Sealing structure of packaging box, production process of sealing structure and packaging box

Abstract

The present invention discloses a sealing structure for a packaging box, a production process for the sealing structure, and a packaging box. The sealing structure comprises: a pull tab, an inner film, and a sealing sheet. The pull tab covers the outside of the opening on the packaging box, the area of ​​the pull tab is larger than the area of ​​the opening, and the sealing sheet matches the shape of the opening and corresponds to the position of the opening. The inner film covers the inside of the opening, the area of ​​the inner film is larger than the area of ​​the opening. Under the action of an external force, the pull tab can cause the inner film to rupture at the opening, thereby opening the opening. Under the action of an external force, the sealing sheet can be embedded in the opening, thereby sealing the opening. By providing the sealing structure of the present invention on the packaging box, the opening of the packaging box can be repeatedly opened and closed, effectively reducing the amount of plastic used, being more environmentally friendly, and lowering production costs.

Description

Technical Field

[0001] The present invention belongs to the technical field of product packaging, and in particular relates to a sealing structure of a packaging box, a production process of the sealing structure, and a packaging box. Background Art

[0002] Non-carbonated liquid foods, such as drinking water, milk, and yogurt, as well as semi-liquid foods like juice, are widely packaged and sold in three-dimensional packaging boxes. These boxes are typically made from paper-based composite packaging materials, which consist of a multi-layered structure consisting of a paper base, a barrier layer (such as aluminum foil), a waterproof layer, and an innermost layer. Once the composite packaging material is produced, it is shipped from the packaging material manufacturer to the food filling company, where it undergoes multiple processes, including filling, sealing, and shaping, to form the liquid food packaging box.

[0003] Liquid food packaging boxes typically use disposable seals or plastic packaging lids. Plastic packaging lids are not only expensive to produce, but also generate large amounts of non-biodegradable plastic waste, placing a heavy burden on the environment. Disposable seals used in liquid food packaging boxes, such as pull-tabs, offer advantages such as ease of opening and low cost, making them ideal for liquid food packaging, especially small-volume liquid food packaging. However, pull-tabs on liquid food packaging boxes can only be opened once and cannot be reclosed after opening, making them unreusable. This makes liquid food packaging boxes with pull-tabs difficult to open and convenient to carry. Summary of the Invention

[0004] In view of the above problems, the present invention discloses a sealing structure of a packaging box, a production process of the sealing structure and a packaging box, so as to overcome the above problems or at least partially solve the above problems.

[0005] In order to achieve the above object, the present invention adopts the following technical solutions:

[0006] On one hand, the present application discloses a sealing structure of a packaging box, wherein the packaging box is made of a composite packaging material, the composite packaging material includes a base layer, a barrier layer, a waterproof layer and an innermost layer, and the sealing structure includes: a pull tab, an inner film and a sealing sheet;

[0007] The pull tab covers the outside of the opening on the packaging box, and the area of ​​the pull tab is larger than the area of ​​the opening. The sealing sheet matches the shape of the opening and corresponds to the position of the opening; the inner film covers the inner side of the opening, and the area of ​​the inner film is larger than the area of ​​the opening.

[0008] Under the action of external force, the pull tab can cause the inner membrane to rupture at the opening to open the opening;

[0009] Under the action of external force, the blocking sheet can be embedded in the opening to achieve sealing of the opening.

[0010] Furthermore, the blocking sheet is located on the inner side of the pull tab, and the inner membrane is fixedly connected to the blocking sheet.

[0011] Furthermore, the blocking sheet is located on the outer side of the pull tab, and the inner membrane is fixedly connected to the pull tab.

[0012] Furthermore, the blocking sheet is located on the inner side of the inner membrane, and the pull tab is fixedly connected to the inner membrane.

[0013] Furthermore, the sealing structure further includes an outer film, which is arranged on the outside of the opening, and the pull tab is arranged on the outside of the outer film.

[0014] Furthermore, the area of ​​the outer film is smaller than the area of ​​the pull tab or the length of the outer film is smaller than the length of the pull tab, and the pull tab portion is fixedly connected to the outer film.

[0015] Furthermore, the material of the blocking sheet is plastic, paper, paper-plastic composite material, or degradable biomaterial.

[0016] Furthermore, the pull tab is a composite material including a barrier material and a fusible material, the barrier material is at least one of aluminum foil or barrier paper, and the fusible material is at least one selected from plastic, PLA or PBAT.

[0017] Furthermore, the inner film is a PE film or a composite film.

[0018] Furthermore, the edge of the sealing sheet is chamfered or provided with a slope.

[0019] Furthermore, a plurality of arc-shaped protrusions or arc-shaped grooves in the horizontal direction are provided on the inclined surface.

[0020] Furthermore, the thickness of the blocking sheet is 1 / 8 to 8 times the thickness of the base layer of the composite packaging material.

[0021] Furthermore, the thickness of the blocking sheet is 2-4 times the thickness of the base layer of the composite packaging material.

[0022] Furthermore, the thickness of one side of the blocking sheet is smaller than the thickness of the other side, and the pull tab is pulled up from the side of the blocking sheet with the smaller thickness.

[0023] Furthermore, the sealing structure further includes a connecting component, which connects the composite packaging material and the pull tab or the sealing sheet.

[0024] Furthermore, the sealing structure further includes a connecting component, which is the end of the pull tab, and the end of the pull tab is connected to the composite packaging material.

[0025] Furthermore, the sealing structure further comprises a connecting component, one end of which is fixedly connected to the inner membrane or the innermost layer near the inner side of the opening, and the other end of which is fixedly connected to the sealing sheet.

[0026] Furthermore, the blocking sheet is a hollow structure and / or the middle portion of the blocking sheet has an opening.

[0027] Furthermore, the blocking sheet is recessed toward the opening side to form a recess.

[0028] Furthermore, the recessed portion of the sealing sheet has an opening.

[0029] On the other hand, the present application discloses a production process for a packaging box sealing structure, the production process comprising the following steps:

[0030] Step S1: punching holes in the composite packaging material to form openings;

[0031] Step S2: Arranging an inner film and a pull tab on the inner side and the outer side of the opening respectively, wherein the areas of the inner film and the pull tab are both larger than the area of ​​the opening;

[0032] Step S3: setting a sealing sheet on the pull tab or the inner membrane, wherein the sealing sheet matches the shape of the opening and corresponds to the position of the opening;

[0033] Step S4: The inner membrane, the blocking sheet and the pull tab are fixedly connected by a heat sealing process or an adhesive process, so that the pull tab can rupture the inner membrane at the opening under the action of an external force, thereby opening the opening; when the blocking sheet is pressed, the blocking sheet can be embedded in the opening, thereby closing the opening.

[0034] Furthermore, the production process also includes:

[0035] Providing an outer membrane outside the opening; or,

[0036] An outer film is arranged on the outside of the composite packaging material, and holes are punched in the area covered by the outer film to form openings.

[0037] Another aspect of the present application discloses a sealing structure for a packaging box, the packaging box being made of a composite packaging material, the composite packaging material comprising a base layer, a barrier layer, a waterproof layer, and an innermost layer, the sealing structure comprising: an inner film and a sealing sheet, the inner film being fixedly connected to the sealing sheet;

[0038] The sealing sheet matches the shape of the opening and corresponds to the position of the opening; the inner membrane covers the inner side of the opening, and the area of ​​the inner membrane is larger than the area of ​​the opening;

[0039] Under the action of external force, the blocking sheet can cause the inner membrane to rupture at the opening, thereby opening the opening; under the action of external force, the blocking sheet can be embedded in the opening, thereby closing the opening.

[0040] Furthermore, the sealing sheet is recessed toward the opening to form a recess and has an edge that is larger than the opening and parallel to the opening, and the edge is used to cover the outer side of the opening on the packaging box.

[0041] Another aspect of the present application discloses a sealing structure for a packaging box, the packaging box being made of a composite packaging material, the composite packaging material comprising a base layer, a barrier layer, a waterproof layer, and an innermost layer, the sealing structure comprising: an inner film and a sealing sheet, the inner film being fixedly connected to the sealing sheet;

[0042] The blocking sheet matches the shape of the opening and corresponds to the position of the opening; the inner membrane covers the inner side of the opening, and the area of ​​the inner membrane is larger than the area of ​​the opening;

[0043] The blocking sheet can cause the inner membrane to rupture at the opening under the action of external force, thereby opening the opening;

[0044] The blocking sheet can be embedded in the opening under the action of external force to achieve sealing of the opening;

[0045] The blocking sheet is recessed toward the opening to form a recess and has an edge that is larger than the opening and parallel to the opening. The edge is used to cover the outer side of the opening on the packaging box, and the recess has an opening.

[0046] On another aspect, the present application discloses a packaging box provided with any of the above-mentioned sealing structures.

[0047] The advantages and beneficial effects of this application are:

[0048] In the sealing structure of the present application, a sealing sheet that matches the shape of the opening is set at the opening position of the composite packaging material, and an external force is applied to the pull tab or sealing sheet set on the outside of the opening, so that the inner film on the inside of the opening position is broken at the opening of the packaging box, thereby realizing the opening; under the action of external force, the sealing sheet can be embedded in the opening to realize the closure of the opening, and then the repeated opening and closing of the packaging box opening can be realized. Compared with the traditional opening method, the sealing sheet effectively reduces the use of plastic, is more environmentally friendly, and reduces the production cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0049] Various other advantages and benefits will become apparent to those skilled in the art upon reading the detailed description of the preferred embodiment below. The accompanying drawings are for illustration purposes only and are not to be considered as limiting the present invention. The same reference symbols are used throughout the drawings to represent the same components. In the drawings:

[0050] Figure 1 This is a longitudinal cross-sectional view of a sealing structure in Example 1 of the present application;

[0051] Figure 2 This is a longitudinal cross-sectional view of another sealing structure in Example 1 of the present application;

[0052] Figure 3 This is a longitudinal cross-sectional view of the sealing structure in Example 2 of the present application;

[0053] Figure 4 This is a longitudinal cross-sectional view of the sealing structure in Example 3 of the present application;

[0054] Figure 5 This is a longitudinal cross-sectional view of another sealing structure in Example 3 of the present application;

[0055] Figure 6 1 is a longitudinal cross-sectional view and a top view of another sealing structure in Example 3 of the present application;

[0056] Figure 7 1 is a longitudinal cross-sectional view and a top view of another sealing structure in Example 3 of the present application;

[0057] Figure 8 This is a longitudinal cross-sectional view of a sealing structure in which the upper and lower edges of the sealing sheet are provided with inclined surfaces in Example 4 of the present application;

[0058] Figure 9 This is a longitudinal cross-sectional view of a sealing structure in which the upper and lower edges of the sealing sheet are chamfered in Example 4 of the present application;

[0059] Figure 10 This is a longitudinal cross-sectional view of a sealing structure having an inclined surface on the upper edge of a sealing sheet in Example 4 of the present application;

[0060] Figure 11 This is a longitudinal cross-sectional view of another sealing structure in Example 4 of the present application, wherein the upper edge of the sealing sheet is provided with a bevel;

[0061] Figure 12 This is a longitudinal cross-sectional view of a sealing structure in which a connecting component is provided on the sealing sheet in Example 4 of the present application;

[0062] Figure 13 This is a diagram illustrating the steps for implementing a production process for a packaging box sealing structure in Example 5 of the present application;

[0063] Figure 14 This is a diagram illustrating the steps for implementing the production process of another packaging box sealing structure in Example 5 of the present application;

[0064] Figure 15 This is a diagram of the production process implementation steps of another packaging box sealing structure in Example 5 of the present application.

[0065] Figure 16 This is a longitudinal cross-sectional view of a sealing structure in Example 6 of the present application;

[0066] Figure 17 2 is a longitudinal cross-sectional view and a top view of another sealing structure in Example 6 of the present application.

[0067] In the figure: 1. pull tab; 2. sealing sheet; 3. composite packaging material; 4. opening; 5. inner membrane; 6. outer membrane; 7. arc-shaped groove; 8. connecting part. DETAILED DESCRIPTION

[0068] To make the objectives, technical solutions, and advantages of the present invention more clear, the following will provide a clear and complete description of the technical solutions of the present invention in conjunction with specific embodiments of the present invention and corresponding drawings. Obviously, the embodiments described are only some of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0069] The technical solutions provided by various embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0070] Example 1

[0071] This embodiment discloses a sealing structure for a packaging box. The packaging box is made of a composite packaging material, and the composite packaging material includes a base layer, a barrier layer, a waterproof layer, and an innermost layer. Among them, the base layer of the composite packaging material is generally made of base paper, such as white-bottomed paper or kraft-bottomed paper. The base layer can provide the necessary stiffness for the composite packaging material, so that the packaging box maintains a stable shape. The barrier layer is crucial for composite packaging materials used for liquid food packaging. It plays a key role in the shelf life of liquid food. Oxygen permeation is the main cause of deterioration of the contents of food packaging. The barrier layer extends the shelf life of the food by preventing oxygen from penetrating into the interior of the packaging container. Aluminum foil is usually used as a barrier layer in composite packaging materials. The waterproof layer is generally a thermoplastic resin, preferably a polyolefin, including but not limited to low-density polyethylene (LDPE), metallocene polyethylene (m-PE), or a mixture of the two. The waterproof layer is located on the outermost side of the composite packaging material, can provide waterproof and dustproof properties, and protect the printed images and text of the composite packaging material from wear. The innermost layer of the composite packaging material is in direct contact with the packaging contents. The innermost layer is typically made of a thermoplastic resin, preferably a polyolefin such as polyethylene (PE), including but not limited to linear low-density polyethylene (LLDPE), ultra-low-density polyethylene (ULDPE), low-density polyethylene (LDPE), metallocene polyethylene (MPE), or mixtures thereof. Adhesive layers are typically provided between the base layer and the barrier layer, and between the barrier layer and the innermost layer. These layers serve to bond the two adjacent layers and are typically made of an adhesive polymer, such as a modified polypropylene-based thermoplastic adhesive polymer. The packaging box is provided with an opening for the contents to flow out or be consumed. This opening is created by punching a hole in the composite packaging material. A sealing structure is provided at the location of the opening to close it.

[0072] like Figure 1 As shown, the sealing structure of this embodiment includes: a pull tab 1, an inner film 5 and a sealing sheet 2.

[0073] The pull tab 1 covers the outside of the opening 4 on the composite packaging material 3. Unless otherwise specified in this application, the outside refers to the side facing the outside air, and the inside refers to the side facing the package contents. The area of ​​the pull tab 1 is larger than the area of ​​the opening 4. The pull tab 1 is generally made of a composite material, and can be a composite material including a barrier material and a fusible material. The barrier material is at least one of aluminum foil or barrier paper, and the fusible material is at least one selected from plastic, PLA, or PBAT. For example, the pull tab 1 is a composite of barrier paper (such as nanocellulose paper) and PE, or a composite of aluminum foil and PE. The barrier paper or aluminum foil can also be replaced by materials such as LDPE (Low-density Polyethylene), HDPE (High Density Polyethylene), PP (Polypropylene), PA (Polyamide), PLA (Polylactic Acid), PBAT (Butyleneadipate-co-terephthalate), paper, etc. A pull tab 1 made of aluminum foil can be fixed by electric heating. This heating causes the PE in the pull tab 1 to melt, thereby bonding the pull tab 1 to the composite packaging material 3. PE can also be replaced with PP, PA, PLA, or PBAT. Pull tabs 1 made of materials other than aluminum foil can be fixed to the composite packaging material 3 by gluing.

[0074] The inner film 5 covers the inner side of the opening 4, and the area of ​​the inner film 5 is larger than that of the opening 4. The inner film 5 can be a PE (Polyethylene) film or a composite film, such as PE laminated on both sides of an EVOH (Ethylene vinyl alcohol copolymer) material, with the EVOH and PE bonded with an adhesive to form a composite material of PE / adhesive / EVOH / adhesive / PE. EVOH can also be replaced with a vapor-deposited film of a metal oxide such as PVOH (Polyvinyl Alcohol), PVDC (Poly-vinylidene Chloride), PA (Polyamide), or Al2O3. This composite material can impart certain barrier properties to the inner film 5, thereby extending the shelf life of the packaged contents.

[0075] In this embodiment, if Figure 1As shown, the blocking sheet 2 is located on the inner side of the pull tab 1, and the portion of the inner film 5 outside the opening 4 is fitted with the innermost layer of the composite packaging material 3. The inner film 5 at the opening 4 is fixedly connected to the blocking sheet 2, that is, the blocking sheet 2 is located between the pull tab 1 and the inner film 5. There can be an opening in the middle of the blocking sheet, and the size of the opening is not limited. Under the action of external force, the blocking sheet can be embedded in the opening, and the blocking sheet and the pull tab jointly achieve the closure of the opening.

[0076] The material of the blocking sheet 2 is plastic, paper, a paper-plastic composite material, or a degradable biomaterial; the blocking sheet 2 can be made of an injection-molded material, such as plastic, specifically PE, preferably LDPE, HDPE, or any one or a combination of PP, PA, PLA or PBAT, such as a combination of PE / PLA; the prepared blocking sheet 2 can be solid or hollow, as long as the shape of the blocking sheet 2 matches the opening 4 and the strength of the material is sufficient to close the opening 4. The hollow blocking sheet can not only further reduce plasticity, but also has better elasticity and can better seal the opening after being embedded. The blocking sheet 2 can also be made of paper or a composite of paper and plastic; of course, the blocking sheet 2 can also be made of other materials, such as wood, bamboo, etc., which are also within the scope of protection of this application. The blocking sheet 2 is formed and then fixed to the pull tab 1. When the blocking sheet 2 is made of an injection-molded material such as plastic, the blocking sheet 2 can be formed first and then fixed to the inner side of the pull tab 1. The blocking sheet 2 can also be directly injection-molded on the inner side of the pull tab 1, and then the pull tab 1 with the blocking sheet 2 is fixed to the composite packaging material 3. During production, the pull tab 1, blocking sheet 2, and inner film can be made of different materials and then combined together by heat sealing or bonding; the pull tab 1, blocking sheet 2, and inner film 5 can also be made of the same material. In this case, the pull tab 1 and the blocking sheet 2 can also be made into an integral part in this embodiment.

[0077] Specifically, the blocking sheet 2 is fixed to the pull tab 1. The blocking sheet 2 matches the shape of the opening 4 and corresponds to the position of the opening 4. One side of the blocking sheet 2 is fixedly connected to the pull tab 1, and the other side of the blocking sheet 2 is fixedly connected to the inner membrane 5. Under the action of an external force, such as when the pull tab 1 is opened or pressed, the binding force between the blocking sheet 2 and the pull tab 1, and the binding force between the blocking sheet 2 and the inner membrane 5 are both greater than the tear strength of the inner membrane 5, thereby tearing the inner membrane 5 at the position of the opening 4, thereby opening the opening 4, and at this time, the liquid can be poured out of the opening 4. Tear strength refers to the force required to tear the inner membrane 5. After opening, the blocking sheet 2 can be pulled out of the opening 4 and / or pushed back, such as by pressing the blocking sheet 2 so that it is embedded in the opening 4, thereby sealing the opening 4. In order to make the blocking sheet 2 better seal the opening 4, the overall size of the blocking sheet 2 can be made slightly larger than the opening 4, or the local size of the blocking sheet 2 can be made slightly larger than the opening 4, so that the contact between the blocking sheet 2 and the edge of the opening 4 is tighter, effectively preventing the liquid in the packaging box from flowing out. An opening can be provided in the middle part of the blocking sheet 2, which can further reduce the amount of plastic used in the blocking sheet 2, making it more in line with the needs of environmental protection and plastic reduction. If an opening is provided in the blocking sheet 2, before the opening 4 is opened or after it is closed again, the blocking sheet 2 mainly closes the opening 4 by the tight closure between its outer edge and the inner edge of the opening 4, and the opening part is closed by the fixed connection between the blocking sheet 2 and the pull tab 1. The blocking sheet 2 can also be a hollow structure and an opening is provided in the middle part of the blocking sheet 2. The hollow structure of the sealing sheet 2 and the opening in the middle thereof can further reduce the amount of plastic used in the sealing sheet 2 and can also make the sealing sheet have better elasticity. After being embedded, it can be more tightly combined with the edge of the opening and can better seal the opening.

[0078] like Figure 1 As shown, the sealing structure may further include: an outer film 6, the outer film 6 being arranged on the outside of the opening 4, and the pull tab 1 being arranged on the outside of the outer film 6; the outer film 6 may be PE (Polyethylene), and the outer film 6 may also be prepared from a composite material of OPP (Oriented Polypropylene) and PE, wherein OPP may also be replaced with a polyester material such as HDPE, PP, PET / PBT, etc. Before punching, the outer film 6 may be pre-set at the pre-punched position of the composite packaging material 3, and holes may be punched in the area covered by the outer film 6 to form the opening 4, wherein the area of ​​the opening 4 is smaller than the area of ​​the outer film 6; alternatively, holes may be punched in the composite packaging material 3 first, and the outer film 6 may be set on the outside of the composite packaging material 3 at the punched position, wherein the area of ​​the outer film 6 is larger than the area of ​​the opening 4, so that the outer film 6 completely covers the opening 4. For its specific structure, please refer to Figure 2When the pull tab 1 comprises aluminum foil, the pull tab 1 is heated electrically so that the pull tab 1 adheres to and is fixed to the composite packaging material 3 with the outer film 6. The outer film 6 prevents damage to the composite packaging material 3 when the pull tab 1 is pulled up due to the strong bonding between the pull tab 1 and the composite packaging material 3 during opening. If the outermost layer of the composite packaging material 3 is a material such as OPP, the outer film is not required because the force of separating the pull tab 1 from the OPP and other materials after bonding will not tear the composite packaging material 3. In addition, considering positioning errors during the process, the width of the pull tab 1 can be set to be slightly narrower than the outer film 6.

[0079] Preferably, the pull tab 1 is only partially attached to the outer film 6. At this time, at least a portion of the pull tab 1 is not fixed to the composite packaging material 3. The area of ​​the outer film 6 can be smaller than the area of ​​the pull tab 1, or the length of the outer film 6 can be smaller than the length of the pull tab 1. The unfixed portion of the pull tab 1 is convenient for lifting the pull tab 1 when opening.

[0080] Furthermore, the sealing structure may also include a connecting component, which is used to prevent the pull tab 1 from completely separating from the packaging box after opening. The connecting component may be a connecting belt or a connecting strip. For example, the connecting component may be integrally injection-molded with the sealing sheet 2 using an injectable material. The sealing sheet 2 is fixed to the pull tab 1, and the connecting component is fixed to the composite packaging material 3. Alternatively, the sealing sheet 2 and the connecting component may be prepared separately, and one end of the connecting component may be fixed to the pull tab 1 or the sealing sheet 2 by gluing or hot-melting, while the other end of the connecting component is fixed to the composite packaging material 3.

[0081] The end of the pull tab 1 can also be set as a connecting component, and one end of the pull tab 1 can be bonded or fixed to the composite packaging material 3. When the pull tab 1 is opened from the other end, it still remains connected to the packaging box to prevent the pull tab 1 from completely detaching from the packaging box, making it easier to store and install the sealing sheet 2 back on the opening 4 after opening.

[0082] The connecting component can also be a part of the composite packaging material 3. For example, when punching a hole in the composite packaging material 3 to form the opening 4, the composite packaging material 3 at the punched position is not completely cut off. The cut composite packaging material 3 is lifted outward from the opening and connected to the pull tab 1. For example, it is connected to the outside of the pull tab 1. The sealing sheet 2 on the inside of the pull tab 1 is bonded to the inner film 5 to seal the opening 4. After opening, the pull tab 1 can still be connected to the packaging box through the cut composite packaging material 3. In addition, the connecting component can also be a limiter or snap mechanism formed by injection molding on the composite packaging material 3. The connecting component ensures that the pull tab 1 is still directly or indirectly connected to the packaging box after opening, making it easier to repeatedly open the opening 4 with the sealing sheet 2.

[0083] Example 2

[0084] This embodiment discloses a sealing structure of a packaging box, which is different from the above embodiment 1 in that Figure 3 As shown, the blocking sheet 2 is located on the outside of the pull tab 1 , and the inner film 5 is fixedly connected to the pull tab 1 , thereby sealing the opening 4 .

[0085] Affix the pull tab 1 to the outside of the opening 4 of the composite packaging material 3, so that the pull tab 1 and the waterproof layer of the composite packaging material 3 outside the opening 4 are in contact. If an outer film 6 is also provided at the opening 4, the pull tab 1 is in contact with the outer film 6 outside the opening 4. If the pull tab 1 comprises aluminum foil, the pull tab 1 can be heated electrically to cause the inner film 5 to contact the pull tab 1 at the opening 4. The portion of the inner film 5 outside the opening 4 is then in contact with the innermost layer of the composite packaging material 3 inside the opening 4, thereby sealing the opening 4.

[0086] The sealing sheet 2 can be made of plastic, paper, a paper-plastic composite, or a biodegradable biomaterial. The sealing sheet 2 can be made of an injection-moldable material, such as plastic, specifically PE, preferably LDPE, HDPE, or any one or a combination of PP, PA, PLA, or PBAT, such as a PE / PLA combination. The pull tab 1 can be first affixed to the outside of the opening 4, and then the sealing sheet 2 can be injection-molded onto the pull tab 1 or a pre-prepared sealing sheet 2 can be bonded to it. Alternatively, the sealing sheet 2 can be pre-fixed to the outside of the pull tab 1 by injection molding or bonding, and then the inside of the pull tab 1 can be attached to the outside of the opening 4 of the composite packaging material 3. The prepared sealing sheet 2 can be solid or hollow, as long as the shape of the sealing sheet 2 matches the opening 4 and the material strength is sufficient to seal the opening 4. During production, the pull tab 1, the blocking sheet 2 and the inner film 5 can be made of different materials respectively, and then combined together by heat sealing or bonding; the pull tab 1, the blocking sheet 2 and the inner film 5 can also be made of the same material. In this case, the pull tab 1 and the blocking sheet 2 can also be made as one piece in this embodiment. An opening can be set in the middle part of the blocking sheet 2. The opening can further reduce the amount of plastic used in the blocking sheet 2, making it more in line with the requirements of environmental protection and plastic reduction. If an opening is set in the blocking sheet 2, before the opening 4 is opened or after it is closed again, the blocking sheet 2 mainly closes the opening 4 by tightly closing between its outer edge and the inner edge of the opening 4, and the opening part is closed by the fixed connection between the blocking sheet 2 and the pull tab 1. The blocking sheet 2 can also be a hollow structure and an opening is set in the middle part of the blocking sheet 2. The hollow structure of the sealing sheet 2 and the opening in the middle thereof can further reduce the amount of plastic used in the sealing sheet 2 and can also make the sealing sheet have better elasticity. After being embedded, it can be more tightly combined with the edge of the opening and can better seal the opening.

[0087] Under the action of an external force, such as lifting or pressing the pull tab 1, the inner film 5 ruptures at the opening 4, thereby opening the opening 4. During opening, the binding force between the sealing sheet 2 and the pull tab 1, as well as the binding force between the pull tab 1 and the inner film 5, is greater than the tear strength of the inner film 5, causing the inner film 5 to tear at the opening 4. After opening, the sealing sheet 2 can be pulled out of the opening 4 and / or pressed back. Pressing can cause the sealing sheet 2 to embed into the opening 4, thereby sealing the opening 4.

[0088] Preferably, if Figure 3 As shown, the sealing structure may further include an outer film 6 disposed outside the opening 4, and a pull tab 1 disposed outside the outer film 6. The outer film 6 may be PE (Polyethylene), or may be made from a composite material of OPP (Oriented Polypropylene) and PE. OPP may also be replaced with a polyester material such as HDPE, PP, or PET / PBT. Before punching, the outer film 6 may be pre-placed at the pre-punched location of the composite packaging material 3, and then a hole may be punched within the area covered by the outer film 6 to form the opening 4, with the area of ​​the opening 4 being smaller than that of the outer film 6. Alternatively, the composite packaging material 3 may be pre-punched, and the outer film 6 may be disposed outside the composite packaging material 3 at the punched location. The area of ​​the outer film 6 should be larger than that of the opening 4, so that the outer film 6 completely covers the opening 4. When the pull tab 1 comprises aluminum foil, the pull tab 1 is heated electrically to adhere to and secure the pull tab 1 to the outer film 6. The outer film 6 can prevent the pull tab 1 from damaging the composite packaging material 3 when opening due to the strong bonding between the pull tab 1 and the composite packaging material 3. In addition, considering the positioning error during the process, the width of the pull tab 1 can be set slightly narrower than the outer film 6.

[0089] Preferably, the pull tab 1 is only partially attached to the outer film 6. At this time, at least a portion of the pull tab 1 is not fixed to the composite packaging material 3. The area of ​​the outer film 6 can be smaller than the area of ​​the pull tab 1, or the length of the outer film 6 can be smaller than the length of the pull tab 1. The unfixed portion of the pull tab 1 is convenient for lifting the pull tab 1 when opening.

[0090] Furthermore, the sealing structure may also include a connecting component, which is used to prevent the pull tab 1 from completely detaching from the packaging box after opening. The connecting component may be a connecting belt or a connecting strip. For example, the connecting component may be integrally injection-molded with the sealing sheet 2 using an injectable material, the sealing sheet 2 being fixed to the pull tab 1, and the connecting component being fixed to the composite packaging material 3. Alternatively, the pull tab 1 may be attached to the composite packaging material 3 or the outer film 6, and then the sealing sheet 2 and the connecting component may be injection-molded on the pull tab 1, and the connecting component may be fixed to the composite packaging material 3. Alternatively, the sealing sheet 2 and the connecting component may be prepared separately, and then one end of the connecting component may be fixed to the pull tab 1 or the sealing sheet 2 by gluing or hot-melting, and the other end of the connecting component may be fixed to the composite packaging material 3.

[0091] The end of the pull tab 1 can also be set as a connecting component, and one end of the pull tab 1 can be bonded or fixed to the composite packaging material 3. When the other end of the pull tab 1 that has not been bonded or fixed to the composite packaging material 3 is opened, it still remains connected to the packaging box, preventing the pull tab 1 from completely detaching from the packaging box, making it easy to store and install the sealing sheet 2 back on the opening 4 after opening.

[0092] The connecting component can also be part of the composite packaging material 3. For example, when punching a hole in the composite packaging material 3 to form the opening 4, the composite packaging material 3 at the punched position is not completely cut or separated. Instead, the cut composite packaging material 3 is lifted outward from the opening and connected to the pull tab 1 or the sealing sheet 2. At the opening 4, the pull tab 1 and the inner film 5 are attached to close the opening 4. After opening, the pull tab 1 or the sealing sheet 2 is connected to the packaging box through the cut composite packaging material 3. In addition, the connecting component can also be in the form of a limiter or snap-fit ​​mechanism injection-molded on the composite packaging material 3. Any structure that allows the pull tab 1 to remain directly or indirectly connected to the packaging box after opening can be considered a connecting component.

[0093] In summary, in the sealing structure of the aforementioned embodiment, a pull tab 1 is provided on the outside of the opening 4 on the composite packaging material 3, and a sealing sheet 2 matching the shape of the opening 4 is provided on the inner or outer surface of the pull tab 1. Under the action of external force, the inner film 5 is ruptured at the opening 4, thereby realizing the opening of the opening 4. Under the action of external force, the sealing sheet 2 can be pulled out of the opening 4 and / or pressed back, thereby realizing repeated opening and closing of the packaging box opening 4, effectively reducing the use of plastic, being more environmentally friendly, and reducing production costs.

[0094] Example 3

[0095] In this embodiment, the area of ​​the blocking sheet 2 is larger than the opening 4. The blocking sheet 2 completely covers the opening 4 and is recessed inwardly at the opening 4 to form a recessed portion. The blocking sheet 2 has an edge that is larger than the opening 4 and parallel to the opening 4. The edge is used to cover the outside of the opening 4 on the packaging box. Figure 4As shown, the blocking sheet 2 located inside the pull tab 1 has an inwardly recessed portion at the opening 4. Figure 5 As shown, the blocking sheet 2 located outside the pull tab 1 has an inwardly concave portion at the opening 4. The concave portion of the blocking sheet 2 can reduce the volume of the blocking sheet 2, thereby significantly reducing the amount of plastic required to form the blocking sheet 2, which is more in line with the requirements of environmental protection and plastic reduction. Furthermore, holes can be formed on the blocking sheet 2 by punching or injection molding, such as Figure 6 As shown, the blocking sheet 2 located inside the pull tab 1 has an inwardly recessed portion with an opening at the opening 4; Figure 7 As shown, the blocking sheet 2 located on the outside of the pull-tab 1 has an inwardly recessed portion with an opening at the opening 4. The opening on the blocking sheet 2 can be used as a straw hole, and the straw can be directly extended into the packaging box through the opening on the blocking sheet 2; when the straw is not in use, the opening 4 can be opened directly through the pull-tab 1, and after opening, the blocking sheet 2 can be pressed back so that the recess of the blocking sheet 2 is embedded in and closes the opening 4. The opening on the blocking sheet 2 provides a more flexible opening method, while also further reducing the amount of plastic used in the blocking sheet 2. The size of the opening is not limited. If an opening is provided in the blocking sheet 2, the opening portion is closed by a fixed connection between the blocking sheet 2 and the pull-tab 1 before the opening 4 is opened or after it is closed again. The sealing structure may also include: an outer film 6, which is provided on the outside of the opening 4 and the inside of the pull-tab 1.

[0096] The prepared sealing sheet 2 can be solid or hollow, as long as its shape matches the opening 4 and its material strength is sufficient to seal the opening 4. The sealing sheet 2 can be made of plastic, paper, a paper-plastic composite, or a biodegradable biomaterial. During production, the pull tab 1, sealing sheet 2, and inner membrane 5 can be made of different materials and then bonded together by heat sealing or bonding. Alternatively, the pull tab 1, sealing sheet 2, and inner membrane 5 can be made of the same material, in which case the pull tab 1 and sealing sheet 2 can be manufactured integrally.

[0097] Example 4

[0098] This embodiment discloses a sealing structure of a packaging box, which is different from the above three embodiments in that Figures 8 to 12 As shown, the blocking sheet 2 is located on the inner side of the inner film 5, and the inner side of the inner film 5 is the side facing the package contents.

[0099] The inner film 5 is set on the inner side of the opening 4 of the composite packaging material 3, and the inner film 5 is heated so that the inner film 5 is in contact with the innermost layer of the composite packaging material 3 at a position outside the opening 4; then the pre-made blocking sheet 2 is fixed at a position on the inner side of the inner film 5 corresponding to the opening 4, or the blocking sheet 2 is formed by injection molding at a position on the inner side of the inner film 5 corresponding to the opening 4.

[0100] The sealing sheet 2 can also be fixed on the inner film 5 first, and then the inner film 5 is attached to the inner side of the opening 4 of the composite packaging material 3. Specifically, the sealing sheet 2 can be formed by injection molding on one side of the inner film 5 or a pre-formed sealing sheet 2 can be fixed, the inner film 5 can be heated, and the other side of the inner film 5 can be attached to the inner side of the opening 4 of the composite packaging material 3 for sealing.

[0101] The sealing sheet 2 is made of plastic, paper, a paper-plastic composite, or a biodegradable biomaterial. The sealing sheet 2 can be solid or hollow, as long as its shape matches the opening 4 and its material strength is sufficient to seal the opening 4. During production, the pull tab 1, the sealing sheet 2, and the inner membrane 5 can be made of different materials and then bonded together by heat sealing or adhesive bonding. Alternatively, the pull tab 1, the sealing sheet 2, and the inner membrane 5 can be made of the same material. For example, in this embodiment, the sealing sheet 2 and the inner membrane 5 can be manufactured integrally.

[0102] During opening, the inner membrane 5 ruptures, and the pull-tab 1, the ruptured portion of the inner membrane 5, and the sealing sheet 2 as a whole exit the opening 4. The sealing sheet 2 may also have an opening in the middle, and the size of the opening is not limited. If the sealing sheet 2 has an opening, before the opening 4 is opened, the opening is sealed by the fixed connection between the inner membrane 5 and the pull-tab 1. After opening, the sealing sheet 2 remains fixedly connected to the pull-tab 1 by the inner membrane 5. After being pulled out of the opening 4, the sealing sheet 2 can be reinserted into the opening 4, and the opening is closed by the pull-tab 1 and the torn inner membrane 5.

[0103] like Figures 8 to 12 As shown, the sealing structure may further include: an outer film 6, which is disposed on the outside of the opening 4, and a pull tab 1 disposed on the outside of the outer film 6; the outer film 6 may be PE (Polyethylene), or may be made of a composite material of OPP (Oriented Polypropylene) and PE. OPP may also be replaced with a polyester material such as HDPE, PP, PET / PBT, etc. During the production process, the outer film 6 may be first bonded to the composite packaging material 3, and then holes may be punched in the area covered by the outer film 6 to form the opening 4; alternatively, holes may be first punched in the composite packaging material 3 to form the opening 4, and then the outer film 6 may be disposed on the outside of the opening 4, with the area of ​​the outer film 6 being larger than that of the opening 4 so that the outer film 6 can completely cover the opening 4.

[0104] Preferably, the pull tab 1 is only partially attached to the outer film 6. In this case, at least a portion of the pull tab 1 is not fixed to the composite packaging material 3. The area of ​​the outer film 6 can be smaller than that of the pull tab 1, or the length of the outer film 6 can be smaller than that of the pull tab 1, so as to facilitate the lifting of the pull tab 1. The inner film 5 and the blocking sheet 2, the inner film 5 and the pull tab 1, and the outer film 6 and the pull tab 1 are fixedly connected by heat sealing, gluing, ultrasonic or inductive means.

[0105] Furthermore, the sealing structure may further include a connecting component, which is used to prevent the pull tab 1 from completely separating from the packaging box after opening. Figure 12 As shown, one end of the connecting member 8 is connected to the inner film 5 surrounding the opening 4. Another end of the connecting member 8 can also be connected to the innermost layer of the composite packaging material 3 near the opening 4. The other end of the connecting member 8 is fixedly connected to the blocking sheet 2. After the pull tab 1 is opened, the blocking sheet 2 remains connected to the packaging box via the connecting member 8, further preventing the blocking sheet 2 from detaching from the packaging box. For example, the connecting member 8 can be a connecting belt or strip, and the connecting member 8 can be integrally injection-molded with the blocking sheet 2 using an injectable material.

[0106] like Figures 8 to 12 As shown, the edge of the blocking sheet 2 is chamfered or provided with a slope, so that the blocking sheet 2 is easier to be embedded in the opening 4 under the action of external force, or the blocking sheet 2 is not easy to be separated from the opening 4 after being embedded in the opening 4, thereby ensuring the firmness of the closure of the opening 4.

[0107] In a preferred embodiment, Figure 11 As shown, the inclined surface is provided with a plurality of horizontal arc-shaped protrusions or arc-shaped grooves 7. When the sealing sheet 2 is inserted into the opening 4, the edge of the opening 4 is exactly located at the connection between the two arc-shaped protrusions or in the arc-shaped groove 7, thereby achieving relative fixation between the sealing sheet 2 and the packaging box, effectively preventing the sealing sheet 2 from escaping from the opening 4, and also preventing the liquid in the packaging box from flowing out.

[0108] The composite packaging material 3 is formed by a multi-layer structure including a paper base layer, a barrier layer (such as aluminum foil), a waterproof layer, an innermost layer, and an adhesive layer. The thickness of the blocking sheet 2 is 1 / 8 to 8 times the thickness of the base layer of the composite packaging material 3. Preferably, the thickness of the blocking sheet 2 is 2 to 4 times the thickness of the base layer of the composite packaging material 3. In one or some embodiments, Figure 12 As shown, the thickness of one side of the blocking sheet 2 is less than that of the other side; when the connecting member is provided on the side with the smaller thickness of the blocking sheet 2 or no connecting member is provided on the blocking sheet 2, the pull tab 1 is pulled up from the side with the larger thickness of the blocking sheet 2. More preferably, when the connecting member 8 is provided on the side with the larger thickness of the blocking sheet 2, the pull tab 1 is pulled up from the side with the smaller thickness of the blocking sheet 2.

[0109] Example 5

[0110] In one embodiment of the present application, a production process of a packaging box sealing structure is disclosed, such as Figure 13 The production process shown includes the following steps:

[0111] Step S1: punching holes in the composite packaging material to form openings.

[0112] Step S2: an inner film and a pull tab are respectively provided on the inner side and the outer side of the opening, wherein the areas of the inner film and the pull tab are both larger than the area of ​​the opening.

[0113] Step S3: a sealing sheet is provided on the pull tab or the inner membrane, wherein the sealing sheet matches the shape of the opening and corresponds to the position of the opening.

[0114] Step S4: The inner membrane, the blocking sheet and the pull tab are fixedly connected by a heat sealing process or an adhesive process, so that the pull tab can rupture the inner membrane at the opening under the action of an external force, thereby opening the opening; when the blocking sheet is pressed, the blocking sheet can be embedded in the opening, thereby closing the opening.

[0115] In one embodiment, Figure 14 As shown, the production process of the packaging box sealing structure also includes:

[0116] An outer film is provided on the outer side of the opening.

[0117] In another embodiment, Figure 15 As shown, the production process of the packaging box sealing structure also includes:

[0118] An outer film is arranged on the outside of the composite packaging material, and holes are punched in the area covered by the outer film to form openings.

[0119] The pull tab is arranged above the outer film, and the pull tab portion is bonded to the outer film. In this case, at least a portion of the pull tab is not fixed to the composite packaging material. For example, the area of ​​the outer film can be smaller than the area of ​​the pull tab, or the length of the outer film can be smaller than the length of the pull tab. The unbonded portion of the pull tab facilitates lifting the pull tab when opening. The pull tab is generally made of composite materials, such as a composite of paper and PE or a composite of aluminum foil and PE. The paper can be a barrier paper, such as nanocellulose paper. Among them, paper or aluminum foil can also be replaced by materials such as LDPE (low-density polyethylene), HDPE (High Density Polyethylene), PP (Polypropylene), PA (polyamide), PLA (Polylactic Acid) or PBAT (butylene adipate-co-terephthalate).

[0120] In one embodiment, a blocking sheet is fixed on the inner side of the pull tab, and the inner film of the composite packaging material is fixedly connected to the blocking sheet at the opening position to seal the opening. One specific method is as follows: a punching device punches a hole in the composite packaging material to form an opening; the inner film is bonded to the inner side of the opening; a blocking sheet is provided on the pull tab, and the blocking sheet matches the shape of the opening. If the blocking sheet is a plastic material, such as plastic, it can be injection molded into a blocking sheet on the inner side of the pull tab by an injection molding device through an injection molding process. Alternatively, the blocking sheet can be formed first, and then the blocking sheet can be fixed on the inner side of the pull tab. The side of the blocking sheet that is not fixed to the pull tab is arranged at the opening position, so that the blocking sheet and the inner film at the opening are fixedly connected together through a heat sealing process or an adhesive process to seal the opening.

[0121] Furthermore, the sealing structure may further include a connecting component, which is used to prevent the pull tab from completely separating from the packaging box after opening. Specifically, the connecting component can be formed by integrally injection-molding the sealing sheet with an injection-molded material. For example, the sealing sheet with the connecting component can be simultaneously injection-molded on one side of the pull tab by an injection molding machine. Alternatively, the sealing sheet with the connecting component can be first injection-molded and then fixed to the pull tab. The sealing sheet and the inner film are then fixedly connected by heat sealing or gluing, and the other end of the connecting component is heat sealed or glued to the composite packaging material.

[0122] The end of the pull tab can also be set as a connecting component, and one end of the pull tab can be bonded or fixed to the composite packaging material. When the other end of the pull tab that has not been bonded or fixed to the composite packaging material is opened, it still remains connected to the packaging box, preventing the pull tab from completely detaching from the packaging box, making it easy to store and install the sealing sheet back on the opening after opening.

[0123] The connecting component can also be a part of the composite packaging material, that is, when a hole is punched on the composite packaging material to form an opening, the composite packaging material at the punching position is not completely cut off; a sealing sheet is fixedly connected to one side of the pull tab, and the cut composite packaging material is also connected to the pull tab; the sealing sheet is bonded to the inner film to seal the opening, and after opening, the pull tab can still be connected to the packaging box through the cut composite packaging material.

[0124] In another embodiment, the blocking sheet is fixed to the outer side of the pull tab, and the inner film is fixedly connected to the pull tab at the opening position of the composite packaging material to seal the opening.

[0125] One specific method is as follows: an outer film is set at the pre-punched position of the composite packaging material, and a punching device punches holes within the coverage of the outer film to form an opening, or an outer film is set on the opening formed by the composite packaging material; the inner film is bonded to the inside of the opening; a sealing sheet is set on the pull tab, and the sealing sheet matches the shape of the opening. If the sealing sheet is a plastic material, such as plastic, it can be injection molded into a sealing sheet on the outside of the pull tab by an injection molding device through an injection molding process. Alternatively, the sealing sheet can be first formed and then fixed to the outside of the pull tab; the side of the pull tab without the sealing sheet is fixedly connected to the inner film at the opening through a heat sealing process or an adhesive process to seal the opening, and after sealing, the position of the sealing sheet corresponds to the position of the opening.

[0126] Furthermore, the sealing structure may further include a connecting component, which is used to prevent the pull tab from completely separating from the packaging box after opening. Specifically, the connecting component can be formed by integrally injection-molding the sealing sheet with an injection-moldable material. For example, the sealing sheet with the connecting component can be simultaneously injection-molded on one side of the pull tab by an injection molding machine. Alternatively, the sealing sheet with the connecting component can be first injection-molded and then fixed to the pull tab. When the pull tab is then fixed to the inner film by heat sealing or gluing, the other end of the connecting component can be simultaneously heat-sealed or glued to the composite packaging material.

[0127] The end of the pull tab can also be set as a connecting component, and one end of the pull tab can be bonded or fixed to the composite packaging material. When the other end of the pull tab that has not been bonded or fixed to the composite packaging material is opened, it still remains connected to the packaging box, preventing the pull tab from completely detaching from the packaging box, making it easier to store and install the sealing sheet back on the opening after opening.

[0128] The connecting component can also be a part of the composite packaging material, that is, when a hole is punched on the composite packaging material to form an opening, the composite packaging material at the punching position is not completely cut off; a sealing sheet is fixedly connected to one side of the pull tab, and the composite packaging material that is cut to form the opening part is connected to the sealing sheet or to the pull tab; the pull tab is bonded to the inner film to close the opening, and after opening, the pull tab can still be connected to the packaging box through the composite packaging material that forms the opening part.

[0129] In another embodiment, the blocking sheet is fixed to the inner side of the inner film and fixedly connected to the inner film. At the opening position of the composite packaging material, the inner film and the pull tab are bonded to close the opening.

[0130] One specific method involves placing an outer film at a predetermined location on the composite packaging material, and then punching holes within the outer film to form an opening. Alternatively, the outer film is placed over the opening formed by the composite packaging material. The inner film is bonded to the inside of the opening, and then a sealing sheet is placed on the inner side of the inner film. Alternatively, a sealing sheet can be placed on one side of the inner film, and then the inner film with the sealing sheet is placed inside the opening. The sealing sheet matches the shape of the opening and is positioned correspondingly to the opening. A pull tab is fixedly connected to the inner film at the opening by heat sealing or gluing to seal the opening.

[0131] Furthermore, the sealing structure may also include a connecting component, which is used to prevent the pull-tab from completely detaching from the packaging box after opening. Specifically, the connecting component can be formed by integrally injection-molding the sealing sheet with an injection-moldable material. For example, the sealing sheet with the connecting component can be simultaneously injection-molded on the inner film by an injection molding machine. Alternatively, the sealing sheet with the connecting component can be first injection-molded and then fixed to the inner film. When the inner film is fixed to the opening position by heat sealing or gluing, the other end of the connecting component is fixed to the innermost layer of the composite packaging material near the opening or to the inner film.

[0132] The end of the pull tab can also be set as a connecting component, and one end of the pull tab can be bonded or fixed to the composite packaging material. When the other end of the pull tab that has not been bonded or fixed to the composite packaging material is opened, it still remains connected to the packaging box, preventing the pull tab from completely detaching from the packaging box, making it easy to store and install the sealing sheet back on the opening after opening.

[0133] In one embodiment, the edges of the blocking sheet are chamfered or beveled.

[0134] Furthermore, a plurality of arc-shaped protrusions or arc-shaped grooves are made on the inclined surface in the horizontal direction.

[0135] Composite packaging materials include base layer, barrier layer, waterproof layer, innermost layer and adhesive layer. The base layer of composite packaging materials is generally made of raw paper, such as white paper or kraft paper.

[0136] In one embodiment, the thickness of the blocking sheet is made to be 1 / 8 to 8 times the thickness of the base layer of the composite packaging material.

[0137] In a preferred embodiment, the thickness of the blocking sheet is made to be 2-4 times the thickness of the base layer of the composite packaging material.

[0138] In one embodiment, when the blocking sheet is manufactured, the thickness of one side of the blocking sheet is made smaller than the thickness of the other side, and the pull tab is preferably pulled up from the side of the blocking sheet with the smaller thickness.

[0139] Example 6

[0140] This embodiment discloses a sealing structure for a packaging box. Unlike Example 1, this embodiment's sealing structure includes an inner film 5 and a sealing sheet 2, but no pull tab. The packaging box is made of a composite packaging material 3, which includes a base layer, a barrier layer, a waterproof layer, and an innermost layer. The sealing structure includes an inner film 5 and a sealing sheet 2. The sealing sheet 2 matches the shape of the opening 4 and corresponds to the position of the opening 4. The inner film 5 covers the inside of the opening 4, and the area of ​​the inner film 5 is larger than that of the opening 4. Under the action of an external force, the sealing sheet 2 can cause the inner film 5 to rupture at the opening 4, thereby opening the opening 4. Under the action of an external force, the sealing sheet 2 can embed into the opening 4, thereby sealing the opening 4.

[0141] The sealing structure may further include an outer film 6, which is disposed outside the opening 4. The sealing sheet 2 is connected to the composite packaging material 3 via the outer film 6. The area of ​​the sealing sheet 2 may be slightly larger than the outer film 6, and an external force may be applied to the portion of the sealing sheet 2 that extends beyond the outer film 6 to open the opening 4.

[0142] like Figure 16 As shown, the area of ​​the blocking sheet 2 is larger than the opening 4, the blocking sheet 2 completely covers the opening 4 and is recessed inwardly at the opening 4 to form a recess, and has an edge larger than the opening 4 and parallel to the opening 4, the edge being used to cover the outside of the opening 4 on the packaging box. Figure 17 As shown, an opening can also be formed in the concave portion of the blocking sheet 2 by punching or injection molding, and the size of the opening is not limited. The opening in the concave portion of the blocking sheet 2 can be used as a straw hole, and the straw can be directly extended into the packaging box through the opening on the blocking sheet 2; when the straw is not in use, the opening 4 can be opened directly through the blocking sheet 2, and after opening, the blocking sheet 2 can be pressed back so that the concave portion of the blocking sheet 2 is embedded in and closes the opening 4. If an opening is provided in the blocking sheet 2, the opening 4 is closed by the inner membrane 5 before the opening 4 is opened, and after opening, the inner membrane 5 ruptures and the opening 4 cannot be closed again. The opening on the blocking sheet 2 provides a more flexible way to open the opening, and can also further reduce the amount of plastic used in the blocking sheet 2.

[0143] Example 7

[0144] In one embodiment of the present application, a production process for a packaging box sealing structure is disclosed, comprising the following steps:

[0145] Punch holes in the composite packaging material to form openings.

[0146] An inner membrane is arranged on the inner side of the opening, and the area of ​​the inner membrane is larger than the area of ​​the opening.

[0147] A blocking sheet is arranged on the outside of the inner membrane, and the blocking sheet matches the shape of the opening and corresponds to the position of the opening.

[0148] The inner membrane and the sealing sheet are fixedly connected through a heat sealing process or an adhesive process, so that the inner membrane can be ruptured at the opening under the action of external force, thereby opening the opening; when the sealing sheet is pressed, the sealing sheet can be embedded in the opening, thereby closing the opening.

[0149] Those skilled in the art will appreciate that, similar to Example 5, the order and proximity of the above steps are not restrictive. For example, the outer film can be placed outside the opening before punching the holes to form the opening. That is, the outer film can be placed outside the composite packaging material first, and then the holes can be punched in the area covered by the outer film to form the opening. Alternatively, the outer film can be placed outside the opening after punching the holes to form the opening and before the inner film is placed inside the opening. Alternatively, the outer film can be placed outside the opening after the inner film is placed inside the opening. Furthermore, a sealing sheet can be placed on the inner film first, and then the combination of the inner film and the sealing sheet can be placed over the opening.

[0150] The bonding method between the adjacent parts is similar to that of Example 5. If an outer film is provided, the sealing sheet is disposed outside the outer film, and the sealing sheet is partially bonded to the outer film. Preferably, the sealing sheet is larger in area than the opening, completely covering the opening and recessed inwardly at the opening to form a recess. The sealing sheet also has an edge that is larger than and parallel to the opening, covering the outside of the opening on the packaging box and bonded to the outermost layer of the composite packaging material or the outer film.

[0151] In one embodiment of the present application, a packaging box is disclosed. The packaging box is provided with a sealing structure according to any of the above embodiments. The packaging box can be repeatedly opened and closed, is easy to carry, and is more environmentally friendly.

[0152] The above description is only a specific embodiment of the present invention. Under the above teachings of the present invention, those skilled in the art may make other improvements or modifications based on the above embodiments. Those skilled in the art should understand that the above description is only to better explain the purpose of the present invention, and the scope of protection of the present invention shall be based on the scope of protection of the claims.

Claims

1. A sealing structure for a packaging box, wherein the packaging box is made of a composite packaging material, wherein the composite packaging material comprises a base layer, a barrier layer, a waterproof layer, and an innermost layer, wherein: The sealing structure includes: a pull tab, an inner membrane and a sealing sheet; The pull tab covers the outer side of the opening on the packaging box, and the area of ​​the pull tab is larger than the area of ​​the opening. The blocking sheet matches the shape of the opening and corresponds to the position of the opening. The inner film covers the inner side of the opening, and the area of ​​the inner film is larger than the area of ​​the opening. The pull tab can cause the inner membrane to rupture at the opening under the action of an external force, thereby opening the opening; The blocking sheet can be embedded in the opening under the action of external force to achieve sealing of the opening; The thickness of one side of the blocking sheet is smaller than the thickness of the other side, and the pull tab is pulled up from the side of the blocking sheet with the smaller thickness; The overall size of the blocking sheet is slightly larger than the opening; and The blocking sheet is a hollow structure and / or the middle portion of the blocking sheet has an opening.

2. The sealing structure according to claim 1, characterized in that: The blocking sheet is located on the inner side of the pull tab, and the inner membrane is fixedly connected to the blocking sheet.

3. The sealing structure according to claim 1, characterized in that: The blocking sheet is located on the outer side of the pull tab, and the inner membrane is fixedly connected to the pull tab.

4. The sealing structure according to claim 1, characterized in that: The blocking sheet is located on the inner side of the inner membrane, and the pull tab is fixedly connected to the inner membrane.

5. The sealing structure according to claim 1, characterized in that: The sealing structure further includes an outer film, which is arranged on the outside of the opening, and the pull tab is arranged on the outside of the outer film.

6. The sealing structure according to claim 5, characterized in that: The area of ​​the outer film is smaller than the area of ​​the pull tab or the length of the outer film is smaller than the length of the pull tab, and the pull tab portion is fixedly connected to the outer film.

7. The sealing structure according to claim 1, characterized in that: The material of the blocking sheet is plastic, paper, or a paper-plastic composite material.

8. The sealing structure according to claim 1, characterized in that: The pull tab is a composite material comprising a barrier material and a fusible material, the barrier material is at least one of aluminum foil and barrier paper, and the fusible material is plastic.

9. The sealing structure according to claim 1, characterized in that: The inner film is a PE film or a composite film.

10. The sealing structure according to claim 1, characterized in that: The edges of the sealing slices are chamfered or provided with inclined surfaces.

11. The sealing structure according to claim 10, characterized in that: The inclined surface is provided with a plurality of arc-shaped protrusions or arc-shaped grooves in the horizontal direction.

12. The sealing structure according to claim 1, characterized in that: The thickness of the blocking sheet is 1 / 8 to 8 times the thickness of the base layer of the composite packaging material.

13. The sealing structure according to claim 12, characterized in that: The thickness of the blocking sheet is 2-4 times the thickness of the base layer of the composite packaging material.

14. The sealing structure according to any one of claims 1 to 13, characterized in that: The sealing structure further includes a connecting component, which connects the composite packaging material and the pull tab or the sealing sheet.

15. The sealing structure according to any one of claims 1 to 13, characterized in that: The sealing structure further includes a connecting component, which is the end of the pull tab, and the end of the pull tab is connected to the composite packaging material.

16. The sealing structure according to claim 4, characterized in that: The sealing structure further comprises a connecting component, one end of which is fixedly connected to the inner membrane or the innermost layer near the inner side of the opening, and the other end of which is fixedly connected to the sealing sheet.

17. The sealing structure according to claim 2 or 3, characterized in that: The blocking sheet is recessed toward the opening to form a recess.

18. The sealing structure according to claim 17, characterized in that: The recess has an opening.

19. A production process for a packaging box sealing structure, characterized in that: The production process comprises the following steps: Step S1: punching holes in the composite packaging material to form openings; Step S2: providing an inner film and a pull tab on the inner side and the outer side of the opening respectively, wherein the areas of the inner film and the pull tab are both larger than the area of ​​the opening; Step S3: providing a blocking sheet on the pull tab or the inner membrane, wherein the blocking sheet matches the shape of the opening and corresponds to the position of the opening; Step S4: The inner membrane, the blocking sheet and the pull tab are fixedly connected by a heat sealing process or an adhesive process, so that the pull tab can cause the inner membrane to rupture at the opening under the action of an external force, thereby opening the opening; when the blocking sheet is pressed, the blocking sheet can be embedded in the opening to close the opening; the thickness of one side of the blocking sheet is smaller than the thickness of the other side, and the pull tab is pulled up from the side of the blocking sheet with a smaller thickness; the overall size of the blocking sheet is slightly larger than the opening; and the blocking sheet is a hollow structure and / or the middle part of the blocking sheet has an opening.

20. The production process according to claim 19, characterized in that The production process also includes: Disposing an outer membrane outside the opening; or, An outer film is arranged on the outer side of the composite packaging material, and holes are punched in the area covered by the outer film to form the opening.

21. A sealing structure for a packaging box, wherein the packaging box is made of a composite packaging material, wherein the composite packaging material comprises a base layer, a barrier layer, a waterproof layer, and an innermost layer, wherein: The sealing structure comprises: an inner membrane and a sealing sheet, wherein the inner membrane is fixedly connected to the sealing sheet; The blocking sheet matches the shape of the opening on the packaging box and corresponds to the position of the opening; the inner film covers the inner side of the opening, and the area of ​​the inner film is larger than the area of ​​the opening; The blocking sheet can cause the inner membrane to rupture at the opening under the action of external force, thereby opening the opening; The blocking sheet can be embedded in the opening under the action of external force to achieve sealing of the opening; The thickness of one side of the blocking sheet is smaller than the thickness of the other side; The overall size of the blocking sheet is slightly larger than the opening; and The blocking sheet is a hollow structure and / or the middle portion of the blocking sheet has an opening.

22. The sealing structure according to claim 21, characterized in that: The blocking sheet is recessed toward the opening to form a recess and has an edge that is larger than the opening and parallel to the opening, and the edge is used to cover the outer side of the opening on the packaging box.

23. A sealing structure for a packaging box, wherein the packaging box is made of a composite packaging material, wherein the composite packaging material comprises a base layer, a barrier layer, a waterproof layer, and an innermost layer, wherein: The sealing structure comprises: an inner membrane and a sealing sheet, wherein the inner membrane is fixedly connected to the sealing sheet; The blocking sheet matches the shape of the opening on the packaging box and corresponds to the position of the opening; the inner film covers the inner side of the opening, and the area of ​​the inner film is larger than the area of ​​the opening; The blocking sheet can cause the inner membrane to rupture at the opening under the action of external force, thereby opening the opening; The blocking sheet can be embedded in the opening under the action of external force to achieve sealing of the opening; The sealing sheet is recessed toward the opening to form a recess, and has an edge that is larger than the opening and parallel to the opening, the edge being used to cover the outer side of the opening on the packaging box, and the recess has an opening; The thickness of one side of the blocking sheet is smaller than the thickness of the other side; The overall size of the blocking sheet is slightly larger than the opening; and The blocking sheet is a hollow structure and / or the middle portion of the blocking sheet has an opening.

24. A packaging box, characterized in that: The packaging box is provided with a sealing structure as described in any one of claims 1-18 and 21-23.

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