CN210062293U

CN210062293U - Medium-temperature-resistant steaming and boiling packaging film and packaging bag

Info

Publication number: CN210062293U
Application number: CN201920760095.5U
Authority: CN
Inventors: 胡钢; 王庆; 张惕; 夏大雁
Original assignee: Jiangyin Green Packing Material Co Ltd
Current assignee: Jiangyin Green Packing Material Co Ltd
Priority date: 2019-05-24
Filing date: 2019-05-24
Publication date: 2020-02-14
Anticipated expiration: 2029-05-24

Abstract

The utility model discloses a moderate temperature resistant packaging film that cooks, for multilayer coextrusion membrane, multilayer coextrusion membrane includes the one deck homo-polypropylene layer in the polyolefin inlayer of at least one deck by table to interior polyolefin inlayer, separation sandwich layer and the heat-seal layer that includes nylon top layer, at least one deck in proper order, and the heat-seal layer is the copolymerization polypropylene layer. The middle-temperature-resistant cooking packaging film adopts the copolymerized polypropylene layer containing the nylon surface layer, the homopolymerized polypropylene layer, the barrier layer and the heat sealing layer, the homopolymerized polypropylene has good fluidity and wide flow rate, the mechanical strength and the heat resistance of the co-extruded film are enhanced, and the long-term heat-resistant stability of the homopolymerized polypropylene meets the use requirement of the cooking packaging film for middle-temperature cooking at 121 ℃. The utility model also discloses a wrapping bag based on resistant medium temperature package film that cooks.

Description

Medium-temperature-resistant steaming and boiling packaging film and packaging bag

Technical Field

The utility model relates to the technical field of films, concretely relates to resistant medium temperature packaging film and wrapping bag of cooking.

Background

The steaming treatment of the packages of food and the like is one of the simplest and most economical sterilization modes, so that the flavor of the food can be maintained, and the shelf life is prolonged. The cooking temperature of the medium-temperature cooking packaging film is about 121 ℃, and the cooking time is 30-40 min. The traditional cooking packaging film has the structure that a surface layer, an aluminum foil or aluminum film and a heat sealing layer are adopted, the film layers are integrally bonded by adopting an adhesive, and the problems of delamination, bulging and the like are easy to occur during medium-temperature cooking treatment. The improved high-temperature cooking packaging film mainly comprises a surface layer, a blocking layer with water and gas blocking functions and a heat sealing layer, wherein the high-temperature cooking packaging film is prepared by co-extrusion, such as CN104669739A and CN202053625U, the film structure in the former scheme is PE/Tie/PP/EVOH/PP/Tie/PE, the film structure in the latter scheme is PA/Tie/PE/Tie/PA/Tie/m-PE, polyethylene is used as the heat sealing layer in the two film structures, and the packaging bag is easy to adhere and deform in the medium-temperature sterilization treatment. In addition, the easy-to-explode packaging bag made of the steamed packaging film is one of the technical problems to be solved urgently by the technical personnel in the field.

SUMMERY OF THE UTILITY MODEL

The utility model discloses an one of the purpose lies in overcoming the defect that exists among the prior art, provides a resistant medium temperature packaging film that cooks, including nylon top layer, medium density polyethylene layer among the multilayer is crowded structure altogether, has good intensity, toughness and separation performance concurrently.

Realize above-mentioned technological effect, the utility model discloses a technical scheme does: the middle-temperature-resistant cooking packaging film is a multilayer co-extrusion film, and the multilayer co-extrusion film sequentially comprises a nylon surface layer, at least one polyolefin inner layer, a barrier core layer and a heat sealing layer from the surface to the inside, and is characterized in that the polyolefin inner layer of at least one layer comprises a homo-polypropylene layer, and the heat sealing layer is a co-polypropylene layer.

The preferred technical scheme is that the barrier core layer is a nylon single layer or a PA/EVOH/PA laminated structure.

The preferred technical scheme is that the nylon surface layer is connected with the polyolefin inner layer, the polyolefin inner layer is connected with the barrier core layer, and the barrier core layer is connected with the heat-sealing layer through bonding resin layers.

The preferable technical scheme is that the barrier film is a nine-layer co-extrusion film, the barrier core layer is a nylon single layer, the nine-layer co-extrusion film comprises three polyolefin inner layers, and the three polyolefin inner layers comprise a polyethylene inner layer and two homo-polypropylene layers.

The preferable technical scheme is that the polyethylene inner layer is bonded with the nylon surface layer through a bonding resin layer.

The preferable technical scheme is that the total film thickness of the medium-temperature-resistant cooking packaging film is 80-150 mu m.

The second objective of the present invention is to provide a packaging bag, which is characterized in that the packaging bag is made by laminating and heat-sealing the heat-sealing layer of the above-mentioned medium temperature steaming and boiling resistant packaging film.

The preferred technical scheme does, the base both ends of wrapping bag are provided with flexible folding strip respectively, one be provided with the orientation on the folding strip the first incision of the bag body, another be provided with dorsad on the folding strip the second incision of the bag body, first incision and second incision looks hookup.

The preferable technical scheme is that the first notch and the second notch are both in a sawtooth shape.

The utility model has the advantages and the beneficial effects that:

the middle-temperature-resistant cooking packaging film adopts the copolymerized polypropylene layer containing the nylon surface layer, the homopolymerized polypropylene layer, the barrier layer and the heat sealing layer, the homopolymerized polypropylene has good fluidity and wide flow rate, the mechanical strength, the heat resistance and the flatness of the co-extruded film are enhanced, and the long-term heat-resistant stability of the homopolymerized polypropylene meets the use requirement of the cooking packaging film for middle-temperature cooking at 121 ℃.

Drawings

FIG. 1 is a schematic structural diagram of an embodiment 1 of the middle temperature cooking resistant packaging film of the present invention;

FIG. 2 is a schematic structural diagram of an embodiment 2 of the middle temperature cooking resistant packaging film of the present invention;

FIG. 3 is a schematic view showing the construction of a packaging bag according to example 3;

FIG. 4 is a schematic view showing the construction of a packaging bag according to example 4;

FIG. 5 is a view showing the use state of the heat-sealed bottom edge of the packaging table of example 4;

FIG. 6 is a right side view of FIG. 5;

in the figure: 1. a nylon surface layer; 2. a layer of homo-polypropylene; 3. a barrier core layer; 4. a layer of co-polypropylene; 5. an adhesive resin layer; 6. a polyethylene layer; 7. packaging bags; 8. a first folding bar; 81. a first cut; 9. a second folding bar; 91. a second incision.

Detailed Description

The following description will further describe embodiments of the present invention with reference to the accompanying drawings and examples. The following examples are only for illustrating the technical solutions of the present invention more clearly, and the protection scope of the present invention is not limited thereby.

Nylon surface layer

The nylon material has strong gas barrier property, is used as a surface layer and has the functions of providing barrier property, surface puncture resistance and tear resistance.

Heat-sealing layer

The heat sealing layer is used for providing a heat sealing surface, and the heat sealing surfaces of the two layers of medium-temperature-resistant cooking packaging films are attached to each other to realize heat sealing connection or heat sealing bag making. The polypropylene copolymer material can provide the heat-sealing temperature of the bottom crossing, and the common polypropylene material of the heat-sealing layer is random polypropylene copolymer, specifically, binary polypropylene copolymer with ethylene monomer added, or ternary polypropylene copolymer with ethylene and butylene monomers added.

Co-extrusion layer number of medium-temperature-resistant cooking packaging film

The number of layers of the medium-temperature cooking resistant packaging film depends on co-extrusion equipment, the number of layers is not particularly limited, common medium-temperature cooking resistant packaging films are 7 or 9, except a nylon surface layer, a first bonding resin layer connected with the nylon surface layer, a second bonding resin layer between a polyolefin inner layer and a barrier layer, a nylon single layer serving as the barrier layer, a third bonding resin layer between the nylon single layer and a heat sealing layer and the heat sealing layer, the number of the polyolefin inner layers is correspondingly one or three, the number of the preferred polyolefin inner layers is three, and further, the structure of the three polyolefin inner layers from the surface to the inner direction along the film thickness is PE/PP/PP.

Thickness or sum of thicknesses of homo-polypropylene layers

The medium temperature cooking resistant packaging film comprises at least one layer of homopolymerization polypropylene layer, wherein the percentage of the thickness or the sum of the thicknesses of the homopolymerization polypropylene layers to the total thickness of the medium temperature cooking resistant packaging film is 20-42%, and the percentage of the sum of the thicknesses of the nylon surface layer and the nylon layer as each layer to the total thickness of the medium temperature cooking resistant packaging film is 10-47%.

If the ratio of the thickness or the sum of the thicknesses of the homo-polypropylene layers is higher than 42%, the brittleness of the packaging film, particularly at low temperatures, is significantly increased. The nylon layer has a thickness higher than 47%, and the sharp portions of the content easily cause stress concentration of the packaging film, thereby causing a decrease in mechanical strength.

The homo-polypropylene and the co-polypropylene have good strength and hardness, and the arrangement of the two sides of the barrier layer is beneficial to enhancing the mechanical strength of the packaging film and simultaneously is beneficial to improving the curling problem of the PA/PE non-paired film forming in the prior art.

Example 1

As shown in fig. 1, the middle-temperature-resistant retort packaging film in example 1 is a nine-layer co-extruded film, which sequentially comprises a nylon surface layer 1, a homo-polypropylene layer 2, a barrier core layer 3 and a co-polypropylene layer 4 (heat-sealing layer) from the surface layer to the inner layer, the laminated structure of the barrier core layer is PA/EVOH/PA, the nylon surface layer 1, the homo-polypropylene layer 2, the barrier core layer 3 and the co-polypropylene layer 4 are connected through an adhesive resin layer 5, and the film structural formula is PA/Tie/PP/Tie/PA/EVOH/PA/Tie/PP.

The thickness of the nylon skin layer 1 was 15 μm, the thickness of the barrier core layer 3 was 40 μm, the thickness of the homo-polypropylene layer 2 was 12 μm, and the thickness of the co-polypropylene layer 4 was 12 μm, as measured for the total thickness of the retort pouch film of example 1, which was 100.2 μm.

Example 1 the PA layer material in the middle temperature retort resistant packaging film was given the designation B40LN +3426, the homo-polypropylene was given the designation R3400, the co-polypropylene was given the designation RB707CF, and the EVOH material was given the designation DT2904 RB.

The longitudinal tensile strength of the medium-temperature-resistant cooking packaging film before embossing is 46.1N/15 mm, and the longitudinal tensile strength is 51.9N/15 mm (detection standard GB/T1040.3); elongation at break in the machine direction of 470% and elongation at break in the transverse direction of 390%; the light transmittance is 87 percent (the detection standard GB/T2410); internal Heat seal Strength 31.29N/15mm (test Standard QB/T2358).

Example 2

As shown in fig. 2, the difference between the example 2 and the example 1 is that the middle temperature cooking resistant packaging film in the example 1 is a nine-layer co-extruded film, which sequentially comprises a nylon surface layer 1, a polyethylene layer 6, two homo-polypropylene layers 2, a nylon single-layer barrier core layer 3, and a co-polypropylene layer 4 (heat-sealing layer) from the surface layer to the inner layer, and the film structural formula is PA/Tie/PE/PP/Tie/PA/Tie/PP.

Example 3

As shown in FIG. 3, example 3 is a packaging bag 7, which is produced by heat-sealing and laminating the heat-seal layers of the retort pouch film of example 1, and the packaging bag of example 3 has a heat-seal width of 10mm, a heat-seal strength of 32.16N/15mm on the left, 32.4N/15mm on the right, a bottom edge of 30.64N/15 mm (detection standard QB/T2358), a haze of 17.47% (detection standard GB/T2410), and no oil stain, crystal spots, black spots, wrinkles, stripes, etc. on the appearance.

Example 4

As shown in fig. 4 to 6, example 4 is based on example 3, and is different in that a first folding strip 8 is provided at one end of the bottom edge of the packaging bag 7, a second folding strip 9 is provided at the other end, a first cut 81 facing the bag body is provided on the first folding strip, a second cut 91 facing away from the bag body is provided on the second folding strip 9, and the first cut 81 and the second cut 91 are hooked. Specifically, the first folding strip and the second folding strip are made of flexible thin films, and the width of the folding strips meets the requirement of notch hooking.

In embodiment 4, after the left and right bottom edges of the packaging bag are heat sealed, the bottom edges are used as a folding template to wind and fold, the folded part is hot pressed, heated and shaped, and then the corresponding notches on the first folding strip 8 and the second folding strip 9 are hooked. When the food is packed, the packing film between the bag bodies of the turnover part is tightly overlapped, so that the moisture in the food is difficult to enter the turnover part, and after the packing bag 7 is vacuumized and heat-sealed, the structure of the turnover part is more stable, namely, the probability of unhooking of the first notch 81 and the second notch 91 is reduced. The packaging bag with the structure provides a buffer space for preventing the bag from being exploded.

In the process of boiling food in water, the room temperature is heated to 98 ℃, the liquid water per se is expanded, the air in the bag is expanded, the bag body is expanded, the air is filled into the turnover part, and the first cut 81 and the second cut 82 which are mutually hooked are opened, so that the bag explosion probability is reduced.

Further, the notches are serrated, reducing the chance of unhooking between the notches during packaging of the food or shelf. For multiple packages requiring the bag to be placed in the outer bag, the bottom-folded bag also reduces the amount of film consumed by the outer bag.

The foregoing is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, a plurality of improvements and decorations can be made without departing from the technical principle of the present invention, and these improvements and decorations should also be regarded as the protection scope of the present invention.

Claims

1. The middle-temperature-resistant cooking packaging film is a multilayer co-extrusion film, and the multilayer co-extrusion film sequentially comprises a nylon surface layer, at least one polyolefin inner layer, a barrier core layer and a heat sealing layer from the surface to the inside, and is characterized in that the polyolefin inner layer of at least one layer comprises a homo-polypropylene layer, and the heat sealing layer is a co-polypropylene layer.

2. The mesophilic digestion-resistant packaging film according to claim 1, wherein the barrier core layer is a nylon monolayer or a laminate structure of PA/EVOH/PA.

3. The middle-temperature-cooking-resistant packaging film according to claim 1, wherein the nylon surface layer is connected with the polyolefin inner layer, the polyolefin inner layer is connected with the barrier core layer, and the barrier core layer is connected with the heat-sealing layer through bonding resin layers.

4. The middle temperature cooking resistant packaging film according to claim 1, wherein the packaging film is a nine-layer co-extruded film, the barrier core layer is a nylon single layer, the nine-layer co-extruded film comprises three polyolefin inner layers, and the three polyolefin inner layers comprise a polyethylene inner layer and two homo-polypropylene layers.

5. The middle temperature cooking resistant packaging film according to claim 4, wherein the polyethylene inner layer is bonded to the nylon surface layer through a bonding resin layer.

6. The middle-temperature-cooking-resistant packaging film according to claim 4, wherein the total film thickness of the middle-temperature-cooking-resistant packaging film is 80-150 μm.

7. A packaging bag which is obtained by applying and heat-sealing the heat-seal layer of the intermediate-temperature-retort-resistant packaging film according to any one of claims 1 to 6.

8. The packaging bag according to claim 7, wherein the two ends of the bottom edge of the packaging bag are respectively provided with a flexible folding strip, one folding strip is provided with a first notch facing the bag body, the other folding strip is provided with a second notch facing away from the bag body, and the first notch and the second notch are hooked.

9. The package of claim 8, wherein the first and second cuts are serrated.