Food filling paper and its preparation method and application

Abstract

The application discloses food filling paper and a preparation method and application thereof. The food filling paper comprises, from inside to outside, a PE film layer, a PET aluminum oxide plating film layer and a kraft paper layer. The kraft paper layer is composed of a kraft paper base layer and a water-based fluorine-free oil-proof coating layer. The food filling paper can meet the requirements of fluorine-free, ultrahigh barrier (12-month shelf life), KIT 7-grade oil-proof and original paper hand feeling retention of the food filling paper at the same time, and breaks through the technical bottleneck that the above performances cannot be combined in the prior art.

Description

Technical Field

[0001] This invention relates to the field of food packaging materials technology, specifically to a food filling paper, its preparation method, and its application. Background Technology

[0002] In the food packaging industry, especially in the filling and packaging of dry foods such as potato chips, popcorn, and nuts, the requirements for packaging materials are extremely stringent. Materials are typically required to possess: ① extremely high oxygen and water vapor barrier properties to extend shelf life; ② excellent oil resistance to prevent food oil leakage; ③ food safety, such as PFAS-free requirements; and ④ good heat-sealing strength to ensure packaging integrity.

[0003] Currently, common solutions on the market have many drawbacks: Fluorinated greaseproof paper: Traditional greaseproof paper often uses fluorinated compounds (such as PFOA and PFOS) to achieve a high greaseproof rating (KIT value), but these substances are harmful to human health and the environment, and do not comply with increasingly stringent environmental regulations. Plastic-feeling composite film: To improve barrier properties, heavy-duty PE lamination or high-thickness plastic composite film is often used, which makes the paper feel hard and slippery, losing the texture of natural paper products, and is difficult to recycle. Uneven performance: Although some products can achieve a high greaseproof rating, their oxygen barrier ratio (O2TR) and moisture barrier ratio (MVTR) cannot meet the requirements for a shelf life of up to 12 months. Summary of the Invention

[0004] The purpose of this invention is to provide a food filling paper, its preparation method, and its application. The food filling paper of this invention can simultaneously meet the requirements of being fluorine-free, having ultra-high barrier properties (12-month shelf life), having KIT 7 level oil resistance, and retaining the original paper feel, thus breaking through the technical bottleneck of the prior art where the above properties could not be achieved simultaneously.

[0005] In order to achieve the above-mentioned objectives of the present invention, the following technical solution is adopted:

[0006] The first aspect of the present invention provides a food filling paper, which comprises, from the inside out, a PE film layer, a PET alumina coating layer, and a kraft paper layer;

[0007] The kraft paper layer consists of a kraft paper base layer and a water-based, fluorine-free, oil-resistant coating.

[0008] Preferably, the food filling paper further includes a printing layer located on the surface of the water-based fluorine-free coating.

[0009] Preferably, the PE film layer, the PET alumina coating layer, and the kraft paper layer are bonded together by adhesive.

[0010] Preferably, the adhesive used for bonding is starch glue.

[0011] Preferably, the PET alumina coating layer consists of an alumina coating and a PET substrate, and the alumina coating is formed on the surface of the PET substrate by vacuum electroplating.

[0012] Preferably, the alumina coating is located between the PE film layer and the PET substrate.

[0013] Preferably, the water-based fluorine-free oil-resistant coating material is a fluorine-free silicone-based food-grade oil-resistant agent.

[0014] A second aspect of the present invention provides a method for preparing the above-mentioned food filling paper, the method comprising the following steps:

[0015] (a) A liquid fluorine-free silicone-based food-grade oil repellent is coated onto the surface of kraft paper and dried to obtain a kraft paper layer;

[0016] (b) An alumina coating is formed on the surface of a PET substrate by vacuum electroplating to obtain a PET alumina coating layer;

[0017] (c) The PET alumina coating layer is bonded to the PE film by adhesive bonding to obtain a PET alumina coating / PE composite layer;

[0018] (d) The kraft paper layer and the PET alumina coating / PE composite layer are bonded together by adhesive to obtain the food filling paper.

[0019] Preferably, the preparation method further includes forming a printing layer on the surface of the kraft paper layer.

[0020] A third aspect of the present invention provides the application of the above-mentioned food filling paper in the preparation of food packaging bags.

[0021] Compared with the prior art, the beneficial effects of the present invention include at least the following:

[0022] This invention is the first in the industry to combine fluorine-free KIT with Grade 7 oil resistance and high barrier properties of alumina, while preserving the original paper's feel. SGS testing shows that all four core indicators meet the standards, making it an industry first.

[0023] The food filling paper of this invention has the following properties:

[0024] Excellent oil resistance: The oil resistance rating reaches KIT 7, which fully meets the oil resistance requirements of dry food packaging;

[0025] Excellent shelf life performance: water vapor permeability is only 0.136 g / (100 in). 2 • 24hr); Oxygen permeability is only 0.160cc / (100in 2 • 24hr) to ensure dried foods remain unspoiled for 12 months;

[0026] Excellent heat seal strength: The heat seal strength reaches 2840 N / m, ensuring a firm and reliable filling seal.

[0027] Environmentally friendly and fluorine-free: Total fluorine content <100mg / kg (not detected), complies with the US TPCH Packaging Materials Act requirements, PFAS-free, safe and environmentally friendly.

[0028] Original paper feel: The special fluorine-free oil-resistant coating provides high oil resistance without changing the original fibrous feel of the kraft paper, avoiding the plastic feel of traditional oil-resistant paper and enhancing the product's quality. Detailed Implementation

[0029] The technical solution of the present invention will be described in detail below with reference to the embodiments. The following embodiments are only used to illustrate the technical solution of the present invention more clearly, and are therefore only examples, and should not be used to limit the scope of protection of the present invention.

[0030] It should be noted that, unless otherwise stated, the technical or scientific terms used in this application should have the ordinary meaning as understood by those skilled in the art to which this invention pertains.

[0031] This invention provides a food filling paper, which comprises, from the inside out, a PE film layer, a PET alumina coating layer, and a kraft paper layer;

[0032] The kraft paper layer consists of a kraft paper base layer and a water-based, fluorine-free, oil-resistant coating.

[0033] In one embodiment, the food filling paper further includes a printing layer located on the surface of the water-based fluorine-free coating.

[0034] In one embodiment, the PE film layer, the PET alumina coating layer, and the kraft paper layer are bonded together by adhesive.

[0035] In one embodiment, the adhesive used for bonding is starch glue.

[0036] In one embodiment, the PET alumina coating layer consists of an alumina coating and a PET substrate, and the alumina coating is formed on the surface of the PET substrate by vacuum electroplating.

[0037] In one embodiment, the alumina coating is located between the PE film layer and the PET substrate.

[0038] In one embodiment, the water-based fluorine-free oil-resistant coating material is a fluorine-free silicone-based food-grade oil-resistant agent.

[0039] Another embodiment of the present invention provides a method for preparing the above-mentioned food filling paper, the method comprising the following steps:

[0040] (a) A liquid fluorine-free silicone-based food-grade oil repellent is coated onto the surface of kraft paper and dried to obtain a kraft paper layer;

[0041] (b) An alumina coating is formed on the surface of a PET substrate by vacuum electroplating to obtain a PET alumina coating layer;

[0042] (c) The PET alumina coating layer is bonded to the PE film by adhesive bonding to obtain a PET alumina coating / PE composite layer;

[0043] (d) The kraft paper layer and the PET alumina coating / PE composite layer are bonded together by adhesive to obtain the food filling paper.

[0044] In one embodiment, the preparation method further includes forming a printing layer on the surface of the kraft paper layer.

[0045] Another embodiment of the present invention provides an application of the above-mentioned food filling paper in the preparation of food packaging bags.

[0046] The technical solution of the present invention will be further described in detail below through specific embodiments.

[0047] Example 1

[0048] This embodiment is a food filling paper, which comprises, from the inside out, a PE film layer (30μm thick), a PET alumina coating layer, and a kraft paper layer;

[0049] The kraft paper layer consists of a kraft paper base layer (80g / m²). 2 It consists of a water-based, fluorine-free, oil-resistant coating.

[0050] The PE film layer, PET alumina coating layer, and kraft paper layer are bonded together using starch adhesive.

[0051] The PET alumina coating layer (12μm) is composed of an alumina coating (50nm) and a PET substrate;

[0052] The alumina coating is located between the PE film layer (40μm) and the PET substrate.

[0053] The water-based fluorine-free oil-resistant coating is made of fluorine-free silicone-based food-grade oil-resistant agent.

[0054] The preparation method of the above-mentioned food filling paper includes the following steps:

[0055] (a) Apply a fluorine-free silicone-based food-grade oil repellent to the surface of kraft paper (2 g / m²). 2 ), dry, and obtain a kraft paper layer;

[0056] (b) An alumina coating is formed on the surface of a PET substrate by vacuum electroplating to obtain a PET alumina coating layer;

[0057] (c) The PET alumina coating layer is bonded to the PE film by adhesive bonding to obtain a PET alumina coating / PE composite layer;

[0058] (d) The kraft paper layer and the PET alumina coating / PE composite layer are bonded together by adhesive to obtain the food filling paper.

[0059] Experimental Example

[0060] The food filling paper prepared in Example 1 was obtained and its performance was tested. The results are shown in Table 1.

[0061] Table 1

[0062]

[0063] As shown in Table 1:

[0064] Fluorine-free verification: Total fluorine content <100mg / kg, which, according to the TPCH Model Legislative Guidance Document, is considered to be free of "intentionally added" PFAS and complies with the U.S. Packaging Materials Act requirements.

[0065] Oil resistance performance: KIT oil resistance rating reaches level 7 (out of 12). The test results of samples 1-5 are all 7, with a standard deviation of 0, indicating that the oil resistance coating is uniform and stable.

[0066] Barrier performance: Water vapor transmission rate (0.136); Oxygen transmission rate (0.160), ensuring a 12-month shelf life.

[0067] Heat sealing performance: The heat sealing strength reaches 2840 N / m, and the failure type is adhesive peeling, indicating that the bond between the heat sealing layer and the composite layer is strong and the filling and sealing reliability is high.

[0068] Hand feel evaluation: According to the sensory evaluation team, the finished product has a matte, rough natural paper feel, which is not significantly different from the original kraft paper and has no plastic feel.

[0069] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention, and they should all be covered within the scope of the claims and specification of the present invention.

Claims

1. A food filling paper, characterized in that, The food filling paper comprises, from the inside out, a PE film layer, a PET alumina coating layer, and a kraft paper layer; The kraft paper layer consists of a kraft paper base layer and a water-based, fluorine-free, oil-resistant coating.

2. The food filling paper according to claim 1, characterized in that, The food filling paper also includes a printing layer located on the surface of the water-based fluorine-free coating.

3. The food filling paper according to claim 1, characterized in that, The PE film layer, PET alumina coating layer, and kraft paper layer are bonded together with adhesive.

4. The food filling paper according to claim 3, characterized in that, The adhesive used for bonding is starch glue.

5. The food filling paper according to claim 1, characterized in that, The PET alumina coating layer consists of an alumina coating and a PET substrate, and the alumina coating is formed on the surface of the PET substrate by vacuum electroplating.

6. The food filling paper according to claim 5, characterized in that, The alumina coating is located between the PE film layer and the PET substrate.

7. The food filling paper according to claim 1, characterized in that, The water-based fluorine-free oil-resistant coating is made of fluorine-free silicone-based food-grade oil-resistant agent.

8. The method for preparing food filling paper according to any one of claims 1 to 7, characterized in that, The preparation method includes the following steps: (a) A liquid fluorine-free silicone-based food-grade oil repellent is coated onto the surface of kraft paper and dried to obtain a kraft paper layer; (b) An alumina coating is formed on the surface of a PET substrate by vacuum electroplating to obtain a PET alumina coating layer; (c) The PET alumina coating layer is bonded to the PE film by adhesive bonding to obtain a PET alumina coating / PE composite layer; (d) The kraft paper layer and the PET alumina coating / PE composite layer are bonded together by adhesive to obtain the food filling paper.

9. The preparation method according to claim 8, characterized in that, The preparation method further includes forming a printing layer on the surface of the kraft paper layer.

10. The use of the food filling paper according to any one of claims 1 to 7 in the preparation of food packaging bags.

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