Low-temperature-resistant, high-barrier and steaming-resistant aluminum foil composite film and food packaging bag

Abstract

The utility model discloses a low-temperature-resistant, high-barrier and steaming-resistant aluminum foil composite film and a food packaging bag, the aluminum foil composite film comprises a heat sealing layer, a first protective layer, a barrier layer, a second protective layer and a printing fabric layer which are laminated in sequence, and the layers are bonded with one another; wherein the heat sealing layer comprises an RCPP film, the first protective layer and the second protective layer respectively comprise a PA film, the blocking layer comprises an Al film, and the printing fabric layer comprises a PET film. The aluminum foil composite film is good in barrier property, not only can keep the original performance of materials in an extremely low temperature environment, but also can resist high temperature cooking, and can meet the requirements of high barrier, low temperature resistance and high temperature cooking resistance at the same time.

Description

TECHNICAL FIELD

[0001] The utility model belongs to the field of food packaging material, concretely relates to a kind of low-temperature-resistant high-barrier steaming-resistant aluminium foil composite film and food packaging bag. BACKGROUND

[0002] In order to keep food clean and sanitary, it is usually necessary to package food during food storage and transportation. Traditional food packaging materials use aluminum foil, plastic and other materials, and by setting multiple functional layers such as barrier layers, impact-resistant layers and other additional functional layers to improve the barrier performance and protective performance of the food packaging material, oxygen, water vapor and other harmful substances are blocked from entering the inside of the food packaging, thereby improving the quality of food preservation and extending the shelf life of food.

[0003] High-temperature-resistant steaming bags are a kind of composite plastic film bags that can be heated. Food can be sterilized and heated at high temperature (usually 120-135°C) in the bag and then eaten. For example, Chinese patent CN203766158U discloses a high-temperature-resistant steaming medicinal-grade composite film composed of a 10-13 micron thick PET layer, a 6-8 micron thick aluminum foil layer and a 30-50 micron thick RCPP layer. A high-temperature-resistant food-grade polyurethane adhesive is provided between adjacent layers. The non-adhesive surface of the PET layer is provided with 5-10 nanometer copolymer PP. Laser anti-counterfeiting stripes are provided on the PET layer, aluminum foil layer or RCPP layer. The aluminum foil layer is provided with a printed pattern. Chinese patent application CN107538837A discloses a composite film for a steaming-resistant packaging bag, which is composed of a first PET layer, an aluminum foil layer, a PA layer or a second PET layer and a RCPP layer arranged in sequence. The adhesive used between the layers is polyurethane adhesive or acrylic adhesive, and the coupling agent used in the polyurethane adhesive or acrylic adhesive is amino silane coupling agent.

[0004] However, in an extremely low temperature environment below -55°C, the high-temperature-resistant steaming food packaging material in the prior art cannot simultaneously meet the requirements of high barrier, extremely low temperature resistance and high-temperature-resistant steaming (usually 120-135°C). In an extremely low temperature environment, the impact resistance of the food packaging bag is poor, and it is easily damaged by external forces during transportation, handling and shelf placement, and the bag is easily broken or opened. This is because the interlayer peeling strength of the packaging bag is small, the tensile strength is not enough, and the mechanical properties of the packaging bag are poor, causing the packaging bag to delaminate and the packaging bag to fail to achieve the desired load-bearing effect, thus failing to effectively protect the contents.

[0005] Since the cold resistance of the food packaging material cannot meet the requirements, the material cannot maintain the original performance under low temperature, the packaging material is brittle, the mechanical strength of the packaging material is reduced, the packaging bag is broken and cracked, and the protection of the contents cannot be met. In order to minimize this phenomenon and reduce the frequency of the influence of the extremely low temperature environment on the mechanical strength of the packaging material, it is necessary to provide a food packaging material which has high barrier, extremely low temperature resistance and high temperature cooking.

[0006] Therefore, the utility model provides a kind of low temperature resistant high barrier cooking resistant aluminium foil composite film. Utility model contents

[0007] The technical problem to be solved by the utility model is to overcome the deficiencies of the prior art, and provide a low temperature resistant high barrier cooking resistant aluminium foil composite film which can maintain the original performance of the material under extremely low temperature environment and resist high temperature cooking, and can meet the requirements of high barrier, extremely low temperature resistance and high temperature cooking.

[0008] To solve the above technical problems, the basic concept of the technical scheme of the utility model is:

[0009] The utility model provides a kind of low temperature resistant high barrier cooking resistant aluminium foil composite film, including heat sealing layer, first protective layer, barrier layer, second protective layer and printing fabric layer that are sequentially laminated, each layer is mutually adhered;Wherein, the heat sealing layer includes RCPP film, the first protective layer and the second protective layer include PA film respectively, the barrier layer includes Al film, and the printing fabric layer includes PET film.

[0010] The low temperature resistant high barrier cooking resistant aluminium foil composite film of the utility model includes heat sealing layer, first protective layer, barrier layer, second protective layer and printing fabric layer that are sequentially laminated. In the five-layer composite film structure, the barrier layer is located in the middle, one layer of protective layer is arranged on the two sides of the barrier layer, the innermost side is provided with a heat sealing layer, and the outermost side can be printed with ink. The barrier layer is an aluminum film, and the barrier property is excellent;The printing fabric layer is PET, and the barrier performance is good, and the strength is high, resistant to high and low temperature;Two layers of protective layer are PA film, and have very strong mechanical properties, high toughness, impact resistance and tear resistance;The heat sealing layer is a cooking grade PP, and can resist 120 DEG C high temperature. Through the arrangement of the structure and the mutual cooperation between the performance of each layer of film material, the composite film as a whole has high barrier property, can prevent water vapor and oxygen from penetrating through, and also has the advantages of high toughness, impact resistance, tear resistance, high temperature resistance and extremely low temperature resistance.

[0011] Further scheme, the thickness of the heat sealing layer is 70-90 microns.

[0012] Further scheme, the thickness of the first protective layer is 12-15 microns.

[0013] In a further aspect, the barrier layer has a thickness of 7-9 microns.

[0014] In a further aspect, the second protective layer has a thickness of 12-15 microns.

[0015] In a further aspect, the printed fabric layer has a thickness of 12-15 microns.

[0016] In a further aspect, the first protective layer and the second protective layer have the same thickness.

[0017] In a specific preferred embodiment, the heat-seal layer has a thickness of 80 microns, the first protective layer has a thickness of 15 microns, the barrier layer has a thickness of 7 microns, the second protective layer has a thickness of 15 microns, and the printed fabric layer has a thickness of 15 microns.

[0018] The aluminum foil composite film of the utility model discloses, the adjacent each layer between all is equipped with adhesive. Adhesive can adopt conventional adhesive in prior art. As an alternative way, adhesive is polyurethane polyol mixture, adapts low temperature environment. The adhesive gumming amount is 4.2~4.5g / square meter.

[0019] In a further aspect, one side of each layer of film that contacts the other is subjected to corona treatment to improve the interlayer bonding strength, and then the layers are compounded by dry or wet compounding processes.

[0020] The utility model discloses still provide a kind of food packaging bag, which is made of the low-temperature-resistant high-barrier and steam-cooking-resistant aluminum foil composite film, and from inside to outside includes heat-seal layer, first protective layer, barrier layer, second protective layer and printed fabric layer which are sequentially laminated.

[0021] Compared with the prior art, the utility model has the following beneficial effects after adopting the above technical scheme:

[0022] 1. The low-temperature-resistant high-barrier and steam-cooking-resistant aluminum foil composite film comprises a heat-seal layer, a first protective layer, a barrier layer, a second protective layer and a printed fabric layer which are sequentially laminated. In the five-layer composite film structure, the barrier layer is located in the middle, one protective layer is arranged on each side of the barrier layer, the heat-seal layer is arranged on the innermost side, and the outermost layer can be printed with ink. The barrier layer is an aluminum film, which has excellent barrier properties. The printed fabric layer is PET, which has good barrier properties, high strength, and resistance to high and low temperatures. The two protective layers are PA films, which have strong mechanical properties, high toughness, impact resistance and tear resistance. The heat-seal layer is a steam-cooking-grade PP, which can withstand high temperatures of up to 120°C. Through the arrangement of this structure and the mutual cooperation between the properties of the various layers of film, the composite film as a whole has high barrier properties, can prevent water vapor and oxygen from penetrating through, and also has the advantages of high toughness, impact resistance, tear resistance, high temperature resistance and extreme low temperature resistance.

[0023] 2. The low-temperature-resistant high-barrier and cooking-resistant aluminum foil composite film has reasonable thicknesses set according to the properties of the layers, and meets the requirements of high barrier, extremely low-temperature resistance and high-temperature cooking resistance at the same time.

[0024] The specific embodiments of the present application will be further described in detail below with reference to the accompanying drawings. BRIEF DESCRIPTION OF DRAWINGS

[0025] The accompanying drawings are part of the present application and serve to provide a further understanding of the present application, and the illustrative embodiments of the present application and the description thereof serve to explain the present application, but do not constitute an improper limitation on the present application. Obviously, the drawings described below are only some embodiments, and other drawings can be obtained by those skilled in the art without creative labor. In the drawings:

[0026] Figure 1 is a sectional view of the low-temperature-resistant high-barrier and cooking-resistant aluminum foil composite film of the present application.

[0027] In the figure: 1, heat sealing layer, 2, first protective layer, 3, barrier layer, 4, second protective layer, 5, printed fabric layer.

[0028] It should be noted that these drawings and written descriptions are not intended to limit the scope of the concept of the present application in any way, but to illustrate the concept of the present application to those skilled in the art by referring to specific embodiments. DETAILED DESCRIPTION

[0029] In order to make the purpose, technical scheme and advantages of the embodiments of the present application more clear, the technical scheme in the embodiments will be described clearly and completely below with reference to the drawings in the embodiments of the present application. The following embodiments are used to illustrate the present application, but not to limit the scope of the present application.

[0030] In the description of the present application, it should be noted that the terms "up", "down", "front", "back", "left", "right", "vertical", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to facilitate the description of the present application and simplify the description, and do not indicate or imply that the devices or elements referred to must have a particular orientation, be constructed and operated in a particular orientation, therefore it cannot be understood as a limitation on the present application.

[0031] In the description of the utility model, it is to be explained that, unless another explicit provision and limitation, the term "installation", "connection", "connect" should be broad sense understanding, for example, can be fixed connection, also can be detachable connection, or integrally connected;Can be mechanical connection, also can be electrical connection;Can be directly connected, also can be indirectly connected through intermediate medium.

[0032] As Figure 1 Indicated, the utility model provides a kind of low-temperature-resistant high-barrier cooking-resistant aluminum foil composite film, including heat-seal layer 1, first protective layer 2, barrier layer 3, second protective layer 4 and printing fabric layer 5 that are sequentially laminated, each layer is mutually adhered;Wherein, the heat-seal layer 1 includes RCPP film, the first protective layer 2 and the second protective layer 4 include PA film respectively, the barrier layer 3 includes Al film, and the printing fabric layer 5 includes PET film.Specifically:

[0033] Heat-seal layer is RCPP film, and RCPP is cooking grade PP, can resist 120 DEG C, waterproof and moistureproof, and cost is low.

[0034] First protective layer and second protective layer are PA film, and PA macromolecular material has better low-temperature resistance, puncture resistance and air barrier and the like, so PA film has the advantages of high toughness, tear resistance, impact resistance, high-temperature resistance, has very strong mechanical properties, prevents the damage of external force to food, and has the effect of protecting food.

[0035] Barrier layer is AL film layer, and AL film has excellent barrier property, and waterproof and moistureproof, but has higher reflection to light and heat, and the disadvantage is low strength, and is not resistant to tension.

[0036] Printing fabric layer includes PET film, and PET has good barrier property, can prevent water vapor and oxygen and the like from permeating, is important aroma-retaining material;Cold resistance and heat resistance are good;BOPET film has the characteristics of high strength, good rigidity, transparency, glossiness and the like;No smell, no taste, no color, no toxicity, outstanding toughness;It has excellent wear resistance, folding resistance, pinhole resistance and tear resistance and the like;Heat shrinkage is very small, only shrinks 1.25% after 15 minutes;It has good heat resistance, excellent cooking resistance, low-temperature freezing resistance, good oil resistance and chemical resistance and the like.

[0037] The low-temperature-resistant high-barrier and steaming-resistant aluminum foil composite film comprises, in sequence, a heat-sealing layer, a first protective layer, a barrier layer, a second protective layer and a printing fabric layer. In this way, the aluminum foil composite film has a five-layer composite structure, the barrier layer is located in the middle, one protective layer is arranged on each side of the barrier layer, the heat-sealing layer is arranged on the innermost side, and the outermost layer can be printed with ink. In this way, on the one hand, the barrier layer is located in the middle, the two protective layers and the inner layer and the outer layer can all protect the barrier layer in the middle, the influence of light and heat on the performance of the barrier layer is avoided, and the barrier performance of the composite film is improved from the physical structure. On the other hand, the barrier layer is an aluminum film, has excellent barrier property; the printing fabric layer is PET, has good barrier performance, high strength and high-temperature and low-temperature resistance; the two protective layers are PA films, have strong mechanical properties, high toughness, impact resistance and tear resistance; and the heat-sealing layer is a steaming-grade PP and can resist 120 DEG C high temperature. The performance of the film materials of the layers can also be matched with each other, so that the composite film as a whole has high barrier performance, can prevent water vapor and oxygen from penetrating through, and also has the advantages of high toughness, impact resistance, tear resistance, high-temperature resistance and extremely low-temperature resistance.

[0038] The aluminum foil composite film of the utility model, each layer between adjacent is equipped with adhesive. The adhesive can adopt conventional adhesive in prior art. As a kind of alternative way, adhesive is polyurethane polyol mixture, adaptation low temperature environment. The adhesive quantity of gumming is 4.2~4.5g / square meter.

[0039] The thickness of the heat-sealing layer 1 is 70-90 microns. The thickness of the first protective layer 2 is 12-15 microns. The thickness of the barrier layer 3 is 7-9 microns. The thickness of the second protective layer 4 is 12-15 microns. The thickness of the printing fabric layer 5 is 12-15 microns.

[0040] In the utility model, heat-sealing layer is located in the innermost side, and the thickness is maximum, keeps the performance that aluminum foil composite film is steaming-resistant. The thickness of first protective layer and second protective layer can be same or different. The thickness of first protective layer and second protective layer is set to same, then can realize double-sided protection to barrier layer, need not specially distinguish.

[0041] As a kind of specific preferred implementation, the thickness of the heat-sealing layer 1 is 80 microns, the thickness of the first protective layer 2 is 15 microns, the thickness of the barrier layer 3 is 7 microns, the thickness of the second protective layer 4 is 15 microns, and the thickness of the printing fabric layer 5 is 15 microns. It is proved by experiment that the tensile strength and toughness of the aluminum foil composite film of the structure in extremely low temperature and high temperature environment are both very good.

[0042] The preparation process comprises:

[0043] (1) first make the film of each layer by blowing film or casting;

[0044] (2) The surface of each layer film which contacts with each other is subjected to corona treatment to improve the interlayer bonding strength, and then is compounded on a compounding machine through dry or wet compounding process. The compounded film through the multi-layer compounding process is subjected to heat sealing and cutting to obtain the aluminum foil composite film.

[0045] The five-layer aluminum foil composite film prepared by the utility model satisfies the performance requirements of light shielding, heat resistance, high barrier, low temperature resistance, low temperature heat sealing and the like.

[0046] Example 1 (PET15 / PA15 / AL7 / PA15 / RCPP80)

[0047] The low-temperature-resistant high-barrier and cooking-resistant aluminum foil composite film of the embodiment comprises, from inside to outside, a heat sealing layer 1, a first protective layer 2, a barrier layer 3, a second protective layer 4 and a printed fabric layer 5 which are sequentially stacked and adhered to each other. The heat sealing layer is an RCPP film with a thickness of 80 microns; the first protective layer is a PA film with a thickness of 15 microns; the barrier layer is an Al film with a thickness of 7 microns; the second protective layer is a PA film with a thickness of 15 microns; and the printed fabric layer is a PET film with a thickness of 15 microns.

[0048] Example 2 (PET15 / PA15 / AL8 / PA15 / RCPP70)

[0049] The low-temperature-resistant high-barrier and cooking-resistant aluminum foil composite film of the embodiment comprises, from inside to outside, a heat sealing layer 1, a first protective layer 2, a barrier layer 3, a second protective layer 4 and a printed fabric layer 5 which are sequentially stacked and adhered to each other. The heat sealing layer is an RCPP film with a thickness of 70 microns; the first protective layer is a PA film with a thickness of 15 microns; the barrier layer is an Al film with a thickness of 8 microns; the second protective layer is a PA film with a thickness of 15 microns; and the printed fabric layer is a PET film with a thickness of 15 microns.

[0050] Example 3 (PET12 / PA12 / AL9 / PA12 / RCPP90)

[0051] The low-temperature-resistant high-barrier and cooking-resistant aluminum foil composite film of the embodiment comprises, from inside to outside, a heat sealing layer 1, a first protective layer 2, a barrier layer 3, a second protective layer 4 and a printed fabric layer 5 which are sequentially stacked and adhered to each other. The heat sealing layer is an RCPP film with a thickness of 90 microns; the first protective layer is a PA film with a thickness of 12 microns; the barrier layer is an Al film with a thickness of 9 microns; the second protective layer is a PA film with a thickness of 12 microns; and the printed fabric layer is a PET film with a thickness of 12 microns.

[0052] Comparative Example 1 (PET15 / AL7 / PA15 / RCPP80)

[0053] Compared with Example 1, the aluminum foil composite film of the present comparative example lacks the second protective layer, and the double PA structure is changed into a single PA structure.

[0054] Specifically, from inside to outside, the five-layer aluminum foil composite film comprises a RCPP film layer with a thickness of 80 microns, a PA film layer with a thickness of 15 microns, an Al film layer with a thickness of 7 microns, a PET film layer with a thickness of 15 microns, and a printing fabric layer.

[0055] Comparative Example 2 (PA15 / AL7 / PA15 / RCPP80)

[0056] Compared with Example 1, the aluminum foil composite film of the present comparative example lacks the printing fabric layer, i.e., lacks the PET film.

[0057] Specifically, from inside to outside, the five-layer aluminum foil composite film comprises a RCPP film layer with a thickness of 80 microns, a PA film layer with a thickness of 15 microns, an Al film layer with a thickness of 7 microns, and a PA film layer with a thickness of 15 microns.

[0058] The aluminum foil composite films prepared in Example 1 and Comparative Examples 1-2 were subjected to performance detection, and the detection methods and results are as follows.

[0059] Detection method: according to GB / T1040.3-2006.

[0060] The specific detection results are shown in the following table.

[0061] Table 1

[0062]

[0063] Note: Lowercase letters represent that there is a significant difference (P<0.05) in the same index of different composite film materials, ** represents that there is a very significant difference (P<0.01) in the same index of the same composite film material at room temperature and after being frozen at-80℃ for 42h, and * represents that there is a significant difference (P<0.05) in the same index of the same composite film material at room temperature and after being frozen at-80℃ for 42h.

[0064] Result analysis:

[0065] Under the condition of room temperature and after being frozen at-80℃ for 42h, the strength and toughness of the five-layer aluminum foil composite film of the present application are better than those of the four-layer composite films in Comparative Examples 1 and 2.

[0066] Compared with Example 1, the PET layer and the AL layer of the aluminum foil composite film of Comparative Example 1 directly contact each other, and a layer of PA film as a protective layer is lacking between the two, and it can be seen that the breaking force, tensile strength, and elongation at break are all reduced.

[0067] Compared with Example 1, the aluminum foil composite film of Comparative Example 2 lacks the PET film layer, and the tensile strength and elongation at break are slightly higher than those of Comparative Example 1, but still far lower than those of Example 1.

[0068] It is shown that the five-layer aluminum foil composite film has excellent strength and toughness at room temperature and extremely low temperature, and can meet the requirements of high barrier, low temperature resistance and high temperature resistance. The tensile strength (transverse and longitudinal) and elongation at break (transverse and longitudinal) can be used as indexes for the performance degradation of the composite material under the influence of temperature. The use of double-layer PA as the protective layer material of the high-temperature-resistant aluminum foil composite film can improve the overall performance of the composite film material.

[0069] Test Example 1

[0070] The aluminum foil composite film of Example 1 was used to make a five-layer aluminum foil composite bag, and then performance detection was carried out.

[0071] The composite bag sample specification is: 295mm x 195mm x 14c, and the sample quantity is 50.

[0072] Detection environment: temperature: 23℃; humidity: 50%RH;

[0073] Judgment basis: refer to GJB 4122A-2015 Military Food Packaging Storage and Transportation Requirements

[0074] The cooking temperature is 121℃.

[0075] The specific detection results are shown in the following table:

[0076] Table 2

[0077]

[0078]

[0079] Detection conclusion: the detected items meet the standard requirements of GJB 4122A-2015 Military Food Packaging Storage and Transportation Requirements.

[0080] The above is only a preferred embodiment of the present application, and is not intended to limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above-mentioned technical content without departing from the scope of the technical solution of the present application, and any simple modification, equivalent change and modification of the above-mentioned technical content without departing from the scope of the technical solution of the present application, all still belong to the scope of the present application.

Claims

1. A low-temperature-resistant, high-barrier, retort-resistant aluminum foil composite film, characterized by, The application relates to a low-temperature-resistant high-barrier and steaming-resistant aluminum foil composite film, which comprises a heat-sealing layer, a first protective layer, a barrier layer, a second protective layer and a printing fabric layer which are sequentially stacked and adhered to each other; the heat-sealing layer comprises an RCPP film; the first protective layer and the second protective layer each comprise a PA film; the barrier layer comprises an Al film; and the printing fabric layer comprises a PET film; one side of each film which is in contact with other films is subjected to corona treatment and then is compounded by dry or wet compounding process.

2. The low temperature resistant, high barrier, retort resistant aluminum foil composite film according to claim 1, characterized in that, The thickness of the heat-sealing layer is 70-90 microns.

3. The low temperature resistant, high barrier, retort resistant aluminum foil composite film of claim 1, wherein, The thickness of the first protective layer is 12-15 microns.

4. The low temperature resistant, high barrier, retort resistant aluminum foil composite film of claim 1, wherein, The thickness of the barrier layer is 7-9 microns.

5. The low temperature resistant, high barrier, retort resistant aluminum foil composite film of claim 1, wherein, The thickness of the second protective layer is 12-15 microns.

6. The low temperature resistant, high barrier, retort resistant aluminum foil composite film of claim 1, wherein, The thickness of the printing fabric layer is 12-15 microns.

7. The low temperature resistant, high barrier, retortable aluminum foil composite film according to any one of claims 1 to 6, characterized in that, The thickness of the first protective layer is the same as that of the second protective layer.

8. The low temperature resistant, high barrier, retortable aluminum foil composite film according to any one of claims 1 to 6, characterized in that, The thickness of the heat-sealing layer is 80 microns, the thickness of the first protective layer is 15 microns, the thickness of the barrier layer is 7 microns, the thickness of the second protective layer is 15 microns, and the thickness of the printing fabric layer is 15 microns.

9. A food packaging bag characterized by The low-temperature-resistant high-barrier and steaming-resistant aluminum foil composite film is made of the aluminum foil composite film according to any one of claims 1-8 and comprises a heat-sealing layer, a first protective layer, a barrier layer, a second protective layer and a printing fabric layer which are sequentially stacked from inside to outside.

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