Fiber-reinforced easy-to-tear packaging structure capable of assisting tearing and application of fiber-reinforced easy-to-tear packaging structure

Abstract

The invention discloses a fiber-reinforced easy-to-tear packaging structure capable of assisting tearing and application thereof. The easy-to-uncover packaging structure comprises a packaging body and an easy-to-uncover film material. The easy-to-tear film material comprises a heat sealing layer, a middle layer and a surface layer, at least the heat sealing layer is internally provided with reinforcing fibers, the reinforcing fibers annularly surround the opening along the hot melting area, and the reinforcing fibers extend into the protruding area at the joint. According to the invention, the reinforced fibers with designed shapes and arrangements are used for transmitting stress, so that the problems that the thin film is easy to damage and is torn from the damaged part when the stress is transmitted through the thin film are avoided; meanwhile, the mechanical property of the packaging structure with the opening is accurately matched in the mode that the packaging structure extends in an annular surrounding mode and extends in the radial direction towards the protruding area, and compared with a grid type arrangement mode, the packaging structure is more suitable for tearing under the condition, so that the tearing success rate of the easy-to-tear structure can be greatly increased, and the tearing experience can be greatly improved; therefore, the product use experience of food, medicine or industrial products is improved, and the user satisfaction is improved.

Description

Technical Field

[0001] The invention relates to the technical field of packaging materials, and in particular to a fiber-reinforced tear-assisted easy-to-peel packaging structure and application thereof. Background Art

[0002] Easy-peel materials are widely used in the packaging of food, medicine, and industrial products. For example, common jelly is usually contained in a cup-shaped packaging body, and then the opening of the cup-shaped body is sealed by hot pressing with an easy-peel film material with a thermoplastic surface. When eating, a tearing force can be applied by using a part of the film that protrudes from the edge and is suspended, so that the annular hot-melt area is detached at one edge to form a "tear". Continuing to apply tearing force can smoothly and completely remove the easy-peel film material from the opening and enjoy the delicious food.

[0003] Not only jelly, but other foods such as biscuits, bread, etc. also have the application of easy-peel film materials and corresponding easy-peel packaging structures. Usually, easy-peel film materials are used to package bag-shaped bodies. In addition, not only in the food field, but also in the packaging of other industrial products and medical supplies, the application of easy-peel materials and structures is very extensive.

[0004] However, due to the uneven process control level of hot pressing packaging, even for common jelly packaging structures, the problem of the easy-to-peel film material not being able to form a "tear" even if the protruding area is completely torn and destroyed during the tearing process often occurs, making it difficult to tear off the easy-to-peel film material; or even if a "tear" is formed, the hot pressing adhesion is too strong when the tearing continues, resulting in the inability to tear off continuously along the opening. It is often encountered that part of the film is damaged during the tearing process while another part of the film remains, which greatly affects the eating experience. In addition, in other applications, if similar problems occur, it will also have an adverse impact on the user experience.

[0005] It can be seen that how to ensure the airtightness and reliability of the easy-to-peel package while taking into account the convenience and success rate of tearing off is an important issue facing technical personnel in this field. Summary of the invention

[0006] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a fiber-reinforced easy-to-remove packaging structure and its application, so as to solve the problem that the easy-to-remove packaging material in the prior art is prone to being unable to be completely torn off and the problem that it is occasionally difficult to tear off.

[0007] In order to achieve the above-mentioned invention object, the technical solution adopted by the present invention includes:

[0008] In a first aspect, the present invention provides a fiber-reinforced, tear-assisted, easy-to-peel packaging structure, comprising a packaging body and an easy-to-peel film material, wherein the packaging body has an opening, the easy-to-peel film material seals the opening by hot-melt, the contact surface between the easy-to-peel film material and the periphery of the opening is a hot-melt zone, a junction is divided in the hot-melt zone, the easy-to-peel film material continues to extend from the junction to the periphery to form a protruding zone, and the protruding zone and the packaging body are not hot-melt bonded;

[0009] Along the direction away from the packaging body, the easy-to-peel film material includes a heat-sealing layer, an intermediate layer and a surface layer, at least the heat-sealing layer is provided with reinforcing fibers, the reinforcing fibers surround the opening in a ring shape along the hot melt zone, and extend into the protruding area at the junction along the direction away from the center of the opening.

[0010] The second aspect of the present invention further provides a packaging material for packaging a target object, which includes the easy-to-peel packaging structure provided by any of the above methods, and the target object is contained in a closed space formed by the packaging body of the easy-to-peel packaging structure and the easy-to-peel film material.

[0011] Based on the above technical solution, compared with the prior art, the beneficial effects of the present invention at least include:

[0012] The easy-to-peel packaging structure provided by the present invention utilizes the designed shape and arrangement of reinforcing fibers to achieve the effect of stress transfer, thereby avoiding the problem of the film being easily damaged and torn from the damaged portion when the stress is transferred through the film. At the same time, the present invention adopts a method of annularly extending around and radially extending toward the protruding area to accurately match the mechanical properties of the packaging structure with an opening, which is more suitable for tearing in this situation than a grid-type arrangement. Therefore, it can greatly improve the tearing success rate of the easy-to-peel structure and enhance the tearing experience, thereby improving the product use experience of food, medicine or industrial products and improving user satisfaction.

[0013] The above description is only an overview of the technical solution of the present invention. In order to enable those skilled in the art to more clearly understand the technical means of the present application and implement them according to the contents of the specification, the following is a description of the preferred embodiments of the present invention in conjunction with detailed drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a schematic cross-sectional structure diagram of an easy-to-remove packaging structure provided by a typical implementation case of the present invention;

[0015] Figure 2 It is a schematic diagram of the planar layout structure of an easy-to-remove packaging structure provided by a typical implementation case of the present invention;

[0016] Figure 3It is a schematic diagram of the planar layout structure of an easy-to-remove packaging structure provided by a typical comparative example of the present invention;

[0017] Figure 4 is a schematic diagram of the planar layout structure of an easy-to-remove packaging structure provided by another typical implementation example of the present invention;

[0018] Figure 5 It is a schematic diagram of the planar layout structure of an easy-to-remove packaging structure provided by another typical implementation case of the present invention. DETAILED DESCRIPTION

[0019] In view of the deficiencies in the prior art, the inventor of this case has proposed the technical solution of the present invention after long-term research and extensive practice. The technical solution, its implementation process and principle will be further explained as follows.

[0020] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0021] Moreover, relational terms such as “first” and “second” are merely used to distinguish one component or method step from another with the same name, but do not necessarily require or imply any such actual relationship or order between these components or method steps.

[0022] A first aspect of an embodiment of the present invention provides a fiber-reinforced, tear-assisted, easy-to-peel packaging structure, comprising a packaging body and an easy-to-peel film material, wherein the packaging body has an opening, the easy-to-peel film material seals the opening by hot-melt, the contact surface between the easy-to-peel film material and the periphery of the opening is a hot-melt zone, a junction is divided in the hot-melt zone, the easy-to-peel film material continues to extend from the junction toward the periphery to form a protruding zone, and the protruding zone is not hot-melt bonded to the packaging body;

[0023] Along the direction away from the packaging body, the easy-to-peel film material includes a heat-sealing layer, an intermediate layer and a surface layer, at least the heat-sealing layer is provided with reinforcing fibers, the reinforcing fibers surround the opening in a ring shape along the hot melt zone, and extend into the protruding area at the junction along the direction away from the center of the opening.

[0024] In the above technical solution, the easy-to-remove packaging structure adopts the idea of ​​fiber reinforcement to improve the tearing efficiency and reduce the difficulty of tearing. The inventors found that since the polymer film material itself is elastic, the tearing force cannot be concentrated on a certain point, but is easily evenly dispersed near the force point, dispersing the tensile force, causing the protruding area as the force-applying component to be damaged and tear. When a slight tear opening is formed, the entire film is very easy to expand and tear at the tear opening, causing the entire film to be torn into multiple parts, resulting in tearing failure; in response to the above findings, the inventors of the present invention first thought of transferring the tearing stress by adding reinforcing fibers instead of using the film itself to transfer it. In this way, since the strength of the reinforcing fibers is significantly stronger than that of the film, they can be regarded as rigid fibers, and basically no tensile deformation occurs. The tearing force is first transmitted to the multiple fibers in the protruding area, and then transmitted to the edge of the hot melt area through the tightest fiber, realizing a tearing opening from the edge, and continuing to transmit the tearing force along the extension direction of the fiber, and finally achieving complete tearing.

[0025] At the beginning, in order to facilitate preparation and reduce costs, the inventors of the present invention adopted a fiber reinforcement method similar to that of the existing commercial "grid tape", that is, the reinforcing fibers were compounded in the heat-sealing layer by using a whole-surface grid (the warp and weft were interwoven into a mesh). However, this would bring two problems. On the one hand, the reinforcing fibers are in the heat-sealing layer, especially in the position close to the interface. If a whole-surface grid is used, the reinforcing fibers will inevitably enter the opening area, and a weakly bonded "channel" will be formed along the reinforcing fibers. It is easy to form an unsecured seal at this channel, which may lead to On the other hand, when pulling force is applied from one side of the protruding area, since the fibers in the grid are evenly distributed and there are also fibers distributed in the film area in the opening, the stress of the grid first gathers toward the center of the circle of the hot-melt area. This is determined by the characteristics of the grid (when the protruding area is lifted, the fibers in the middle of the central axis are tightened first). Therefore, the hot-melt area film around it is easily subjected to equal centripetal pulling force, causing the reinforcing fibers to be pulled out of the film along the direction of the fiber axis, which will still lead to tearing failure.

[0026] Based on the above practical findings, the inventors of the present invention finally adopted a ring-shaped fiber layout, in which the reinforcing fibers are only within the hot melt zone and surround the opening, extending circumferentially to both sides along the trajectory of film detachment during tearing, thereby avoiding the disadvantages of the above-mentioned grid-type reinforcing fibers, greatly improving the tearing success rate, and avoiding the negative impact on packaging reliability.

[0027] Furthermore, the diameter of the reinforcing fiber is 0.5-1.5 times the thickness of the heat-sealing layer, and the cross section of the reinforcing fiber is tangent to the interface between the heat-sealing layer and the packaging body.

[0028] Generally, in combination with the preparation method described below, the diameter of the reinforcing fiber is generally not greater than the thickness of the heat sealing layer, so that the fiber is only embedded in the heat sealing layer during hot pressing and does not protrude from the surface of the heat sealing layer; a preferred method is that the diameter of the reinforcing fiber is substantially equivalent to the thickness of the heat sealing layer, for example, 0.8-1.0 times the thickness of the heat sealing layer. At this time, through hot pressing and embedding, the reinforcing fiber is embedded in the heat sealing layer and is basically close to the middle layer. When tearing off, the peeling force can be applied to the heat sealing layer itself, and can also be transferred to the middle layer, and the adhesive force between the middle layer and the heat sealing layer is used to further pull the heat sealing layer, thereby improving the tearing efficiency.

[0029] As for the specific fiber arrangement form, further, in the hot melt zone, the reinforcing fibers are wrapped in multiple layers around the opening in an annual ring or spiral shape; in the protruding zone, each of the reinforcing fibers entering the protruding zone extends at least beyond the geometric center point of the protruding zone.

[0030] More specifically, further, if a point located opposite to the protruding area in a circle around the opening is taken as a dividing point, the reinforcing fibers are divided into a first segment and a second segment, the first segment extends along the first side of the dividing point to the junction, and the second segment extends along the second side of the dividing point to the junction; at the junction, after the first segment crosses the second segment, the first segment extends into the second side of the dividing point and continues to extend toward the end direction of the protruding area, and the second segment extends into the first side of the dividing point and continues to extend toward the end direction of the protruding area.

[0031] Since the joint is the key part of stress transmission, at this position, the stress is transferred from the radial direction of the opening to the circumferential direction. Therefore, the stability and rigidity of the fiber structure at this position are very important for forming an effective tearing hole and the continued extension of the tearing hole. Therefore, in the present invention, compared with the general idea of ​​parallel arrangement and extension to the protruding area, the preferred embodiment of the present invention adopts a cross-extension method. The stress from the left side is transferred to the right side after the crossing, and the stress from the right side is transferred to the left side after the crossing. In addition, in the intersection area, the fibers below will exert an upward pressure on the fibers above to help lift them. Under multiple effects, this method is very helpful in improving the tearing efficiency and experience.

[0032] Furthermore, one way is simple cross-overlapping, that is, multiple first segments are located below, and multiple second segments are overlapped on top of the first segments. Since the fiber diameter is generally close to the thickness of the heat-sealing layer, at this time, at the joint, part or all of the first segments are in the heat-sealing layer, and part or all of the second segments are in the middle layer.

[0033] Furthermore, the present invention also provides another preferred embodiment, that is, at the junction, multiple first segments and multiple second segments are interwoven into a fabric structure (such as a common knitted structure with warp and weft interlaced up and down), and the total thickness of the fabric structure is greater than the thickness of the heat sealing layer. At this time, both the first segment and the second segment will enter the middle layer.

[0034] Furthermore, outside the geometric center of the protruding area, the first segment and the second segment are connected to form a continuous fiber. Of course, it is not excluded that the first segment and the second segment are not connected, but independently extend to the outside of the protruding area. Generally, the extension distance is not less than half of the protruding area, so that each fiber can fully receive the force pulling the protruding area.

[0035] Taking into account the balance between heat sealing performance and tearing performance, the present invention also experimentally determines the fiber spacing, that is, further, in the hot melt zone, the spacing between two adjacent circles or two adjacent turns of the reinforcing fibers is 10-30 times the diameter of the reinforcing fibers.

[0036] If it is less than the minimum value of the above range, the fibers are too dense, resulting in a small area for actual hot pressing bonding, which may lead to a loose bond. If it is greater than the maximum value of the above range, the fibers are too sparse, resulting in the stress transfer of the fibers not being able to match the bonding force between the fibers, which may cause the fibers to be pulled out while the film continues to bond. Therefore, in actual applications, the fiber spacing needs to be controlled to achieve the best effect.

[0037] Furthermore, the preparation method of the easy-to-peel film material comprises:

[0038] Providing a film embryo, wherein the film embryo comprises a heat-sealing layer, an intermediate layer and a surface layer stacked in sequence;

[0039] Laying reinforcing fibers of corresponding shapes on the surface of the heat-sealing layer;

[0040] The reinforcing fibers are embedded in the heat-sealing layer by means of heat pressing to obtain the easy-to-peel film material.

[0041] Furthermore, the melting temperature of the intermediate layer is higher than the melting temperature of the heat sealing layer.

[0042] Furthermore, when part of the reinforcing fibers are required to enter the middle layer, the temperature of the hot pressing is higher than the melting temperature of the middle layer.

[0043] The second aspect of the present invention further provides a packaging material for packaging a target object, which includes the easy-to-peel packaging structure provided by any of the above methods, and the target object is contained in a closed space formed by the packaging body of the easy-to-peel packaging structure and the easy-to-peel film material.

[0044] The technical solution of the present invention is further described in detail below through several embodiments and in conjunction with the accompanying drawings. However, the selected embodiments are only used to illustrate the present invention, and do not limit the scope of the present invention.

[0045] Example 1

[0046] The cross-section and planar layout of the easy-to-peel package structure provided in this embodiment are as follows: Figure 1 and 2 shown.

[0047] The ring layout is adopted, and the overall reinforcement fiber is in the shape of an annual ring, and the part in the convex area will "turn" toward the convex area and part of it will enter the convex area, finally forming Figure 2 Fiber layout shown.

[0048] In this embodiment, the film material has a three-layer structure, the surface layer material is a PP material that has been surface corona treated, and has a thickness of about 5 μm; the middle layer is 60wt% of a low-density polyethylene resin (BASF 2420H) and 40wt% of a high-density polyethylene resin (Total C912A), and has a thickness of about 20 μm; the heat-sealing layer is a mixture of an easy-to-peel polyethylene masterbatch, the masterbatch being 60wt% of a coated low-density polyethylene resin (Yanshan Petrochemical), 25wt% of a high-density polyethylene resin and 15wt% of a polybutene resin, and has a thickness of about 15 μm.

[0049] The film of this embodiment is prepared by a co-extrusion film blowing method, specifically: the raw materials corresponding to the above-mentioned layers are co-extruded, and then obtained by air ring blowing, cooling, and shaping. The three barrel temperatures of the extruder are set to be 160°C for the first stage, 175°C for the second stage, and 190°C for the third stage, and the die head temperature is 200°C; the blowing ratio during film blowing is about 2. After co-extrusion, fibers of corresponding shapes are laid, and hot extrusion is performed again. The extrusion temperature is controlled at 210-215°C to ensure that the fibers are squeezed into the film.

[0050] When tearing, an upward pulling force is applied to the protruding area, so that the force of the protruding area is transmitted through the reinforcing fibers therein. When it is transmitted to the joint, the fibers begin to generate a very concentrated stress on the nearby bonding interface, causing the interface to detach and form a breach. The stress continues to be transmitted along the fibers to the surrounding areas, and eventually the film will be smoothly torn off along the breach.

[0051] It should be noted that the specific film material components and proportions, as well as the specific preparation process in this embodiment are only for illustrative purposes, and do not mean that the method of the present invention can be applied to the materials provided in this embodiment; in fact, the successful application of the method provided by the present invention mainly depends on the structural design provided, rather than on a specific material or process. The selected components and processes can achieve the corresponding functions. Those skilled in the art can develop and design on their own or refer to any prior art literature.

[0052] Example 2

[0053] This embodiment is substantially the same as Embodiment 1, and the main difference is that:

[0054] The fiber arrangement of the multiple loops in Example 1 is modified into a multi-turn spiral shape, and the effect is exactly the same as that of Example 1.

[0055] Comparative Example 1

[0056] The fiber arrangement of this comparative example is as follows Figure 3 shown.

[0057] This comparative example is the preliminary idea of ​​the inventor of the present invention during the research and development process, and uses a method similar to a grid tape to form an easy-to-peel thin film material.

[0058] However, this method is not easy to form a strong heat seal on the one hand, and on the other hand, due to the problem of fiber arrangement, there is obviously greater resistance when tearing, and it is not easy to gradually separate along the tear, and the fibers in a part of the area will be pulled out, resulting in film residue.

[0059] Example 3

[0060] This embodiment is substantially the same as Embodiment 1, the main difference being the arrangement of fibers at the joints and the protruding areas. The large circular rings formed by the fibers cross at the joints and then continue to extend into the protruding areas to form small circular rings in the opposite direction, similar to the shape of a number 8.

[0061] In this embodiment, due to the existence of the cross-fiber structure, when tearing, it can be clearly felt that the tearing force required is smaller than that in Embodiment 1, and the tear and the extension of the tear can be easily achieved.

[0062] Example 4

[0063] This embodiment is substantially the same as the third embodiment, the main difference being that the fibers at the joints are not overlapped up and down, but interwoven to form a warp and weft fabric structure.

[0064] Compared with Example 3, the tearing experience of this embodiment is further improved and smoother.

[0065] Based on the above embodiments and comparative examples, it can be clearly seen that the easy-to-peel packaging structure provided in the embodiments of the present invention utilizes the designed shape and arrangement of reinforcing fibers to achieve the effect of stress transfer, thereby avoiding the problem of the film being easily damaged and tearing from the damaged portion when the stress is transferred through the film. At the same time, the present invention adopts a method of annularly extending around and radially extending toward the protruding area to accurately match the mechanical properties of the packaging structure with an opening, which is more suitable for tearing under such circumstances than a grid-like arrangement. Therefore, it can greatly improve the tearing success rate of the easy-to-peel structure and enhance the tearing experience, thereby improving the product use experience of food, medicine or industrial products and improving user satisfaction.

[0066] It should be understood that the above embodiments are only for illustrating the technical concept and features of the present invention, and their purpose is to enable people familiar with the technology to understand the content of the present invention and implement it accordingly, and they cannot be used to limit the protection scope of the present invention. Any equivalent changes or modifications made according to the spirit of the present invention should be included in the protection scope of the present invention.

Claims

1. A fiber-reinforced, tear-assisted easy-to-peel packaging structure, characterized in that: The invention comprises a packaging body and an easy-to-peel film material, wherein the packaging body has an opening, the easy-to-peel film material seals the opening by heat-melting, the contact surface between the easy-to-peel film material and the periphery of the opening is a heat-melting zone, a junction is divided in the heat-melting zone, the easy-to-peel film material continues to extend from the junction to the periphery to form a protruding zone, and the protruding zone is not heat-melted with the packaging body; It is characterized in that, along the direction away from the packaging body, the easy-to-peel film material includes a heat-sealing layer, an intermediate layer and a surface layer, at least the heat-sealing layer is provided with reinforcing fibers, the reinforcing fibers surround the opening in a ring shape along the hot melt zone, and extend into the protruding area at the junction along the direction away from the center of the opening.

2. The easy-to-remove packaging structure according to claim 1, characterized in that: The diameter of the reinforcing fiber is 0.5-1.5 times the thickness of the heat sealing layer, and the cross section of the reinforcing fiber is tangent to the interface between the heat sealing layer and the packaging body.

3. The easy-to-remove packaging structure according to claim 2, characterized in that: In the hot melt zone, the reinforcing fibers are wrapped in multiple layers around the opening in a ring-like or spiral shape; In the protruding area, each of the reinforcing fibers entering the protruding area at least extends beyond a geometric center point of the protruding area.

4. The easy-to-remove packaging structure according to claim 3, characterized in that: If a point located opposite to the protruding area in a circle around the opening is taken as the dividing point, the reinforcing fibers are divided into a first segment and a second segment, the first segment extends along the first side of the dividing point to the junction, and the second segment extends along the second side of the dividing point to the junction; at the junction, after the first segment crosses the second segment, the first segment extends into the second side of the dividing point and continues to extend toward the end direction of the protruding area, and the second segment extends into the first side of the dividing point and continues to extend toward the end direction of the protruding area.

5. The easy-to-remove packaging structure according to claim 4, characterized in that: At the junction, part or all of the first segment is in the heat-sealing layer, and part or all of the second segment is in the middle layer; Or, at the joint, a plurality of the first segments and a plurality of the second segments are interwoven into a fabric structure, and the total thickness of the fabric structure is greater than the thickness of the heat-sealing layer.

6. The easy-to-remove packaging structure according to claim 4, characterized in that: Outside the geometric center of the protruding area, the first segment and the second segment are connected to form an integral continuous fiber.

7. The easy-to-remove packaging structure according to claim 3, characterized in that: In the hot melting zone, the spacing between two adjacent circles or two adjacent turns of the reinforcing fibers is 10-30 times the diameter of the reinforcing fibers.

8. The easy-to-remove packaging structure according to claim 1, characterized in that: The preparation method of the easy-to-peel film material comprises: Providing a film embryo, wherein the film embryo comprises a heat-sealing layer, an intermediate layer and a surface layer stacked in sequence; Laying reinforcing fibers of corresponding shapes on the surface of the heat-sealing layer; The reinforcing fibers are embedded in the heat-sealing layer by means of heat pressing to obtain the easy-to-peel film material.

9. The easy-to-remove packaging structure according to claim 8, characterized in that: The melting temperature of the intermediate layer is higher than the melting temperature of the heat sealing layer; And / or, when part of the reinforcing fibers are required to enter the middle layer, the temperature of the hot pressing is above the melting temperature of the middle layer.

10. A packaging material for packaging a target object, characterized in that: The easy-to-peel packaging structure comprises the easy-to-peel packaging structure as described in any one of claims 1 to 9, wherein the target object is contained in a closed space formed by the packaging body of the easy-to-peel packaging structure and the easy-to-peel film material.

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