Composite film bag with foaming layer for facial mask packaging and preparation method thereof

Abstract

The invention relates to the technical field of polymer packaging materials, and proposes a composite film bag with a foaming layer for facial mask packaging and a preparation method thereof. The composite film bag comprises a foaming PE film layer, a functional layer and a decorative layer from bottom to top; the functional layer comprises the following raw materials by weight: 100 parts of PET, 10-20 parts of PEN, 6-8 parts of compatibilizer, 10-12 parts of filler, and 1-1.5 parts of antioxidant; the compatibilizer is composed of epoxy compound and polyvinyl alcohol. Through the above technical scheme, the problems of low barrier properties, low recognition and low material utilization rate of composite film bags for facial mask packaging in the related art are solved.

Description

Technical Field

[0001] The invention relates to the technical field of polymer packaging materials, and in particular to a composite film bag with a foaming layer for facial mask packaging and a preparation method thereof. Background Art

[0002] With the rapid development of the domestic economy and the improvement of people's living standards, the facial mask market has expanded rapidly, and many facial mask brands have been born. The demand for facial mask packaging bags in the facial mask market has also gradually increased. In terms of packaging, the materials of facial mask packaging bags among various facial mask brands are mostly aluminum foil composite films or paper-plastic composite films. The differentiation is achieved only by pattern design, and there is a problem of low recognition. Based on environmental protection requirements, packaging reduction has also put forward new requirements for facial mask plastic packaging; moreover, in order to ensure the quality and safety of facial masks during storage and transportation, facial mask plastic packaging should also have good barrier properties, maintain the moisturization of facial masks, the stability of effective ingredients, etc. Because it is necessary to develop a facial mask packaging bag with high barrier properties, packaging bag reduction, and high recognition. Summary of the invention

[0003] The present invention provides a composite film bag with a foaming layer for facial mask packaging and a preparation method thereof, which solves the problems of low barrier properties, low recognition and low material utilization rate of the composite film bag for facial mask packaging in the related art.

[0004] The technical solution of the present invention is as follows:

[0005] The present invention proposes a composite film bag for facial mask packaging with a foaming layer, wherein the composite film bag comprises a foaming PE film layer, a functional layer and a decorative layer from bottom to top; the functional layer comprises the following raw materials in parts by weight: 100 parts of PET, 10 to 20 parts of PEN, 6 to 8 parts of a compatibilizer, 10 to 12 parts of a filler, and 1 to 1.5 parts of an antioxidant; the compatibilizer consists of an epoxy compound and polyvinyl alcohol.

[0006] As a further technical solution, the epoxy compound includes one or more of γ-glycidyloxypropyltrimethoxysilane, 3-[(phenylmethyl)amino]-3-oxetanemethylamine, and 4-(oxiranylmethoxy)phenylacetamide.

[0007] As a further technical solution, the epoxy compound is 4-(oxiranylmethoxy)benzeneacetamide.

[0008] The present invention finds that when the epoxy compound is 4-(oxiranylmethoxy)benzeneacetamide, the barrier properties of the composite film bag and the tensile strength of the functional layer can be better improved.

[0009] As a further technical solution, the mass ratio of the epoxy compound to polyvinyl alcohol is 2~4:1.

[0010] The present invention finds that when the mass ratio of epoxy compound to polyvinyl alcohol is 2-4:1, the interface defects can be better reduced, the barrier properties of the composite film bag can be improved, and the functional layer can maintain a high tensile strength.

[0011] As a further technical solution, the mass ratio of the epoxy compound to polyvinyl alcohol is 3:1.

[0012] As a further technical solution, the filler includes one or more of silicon dioxide, montmorillonite, and mica.

[0013] As a further technical solution, the antioxidant includes one or more of antioxidant 1010, antioxidant 168, and antioxidant 1076.

[0014] As a further technical solution, the density of the PET is 1.20-1.70 g / cm 3 .

[0015] As a further technical solution, the PET consists of a first PET and a second PET, and the first PET and the second PET have different densities.

[0016] As a further technical solution, the density of the first PET is 1.51 g / cm 3 The density of the second PET is 1.2g / cm 3 .

[0017] As a further technical solution, the mass ratio of the first PET to the second PET is 3:1.

[0018] As a further technical solution, the foamed PE film layers are layer A, layer B, and layer C from bottom to top;

[0019] The A layer comprises raw materials of the following components: low-density polyethylene I, linear low-density polyethylene I;

[0020] The B layer includes the following raw materials: low-density polyethylene II, linear low-density polyethylene II, high-density polyethylene, and foaming masterbatch;

[0021] The C layer comprises the following raw materials: low-density polyethylene III, metallocene linear low-density polyethylene, and linear low-density polyethylene with an anti-blocking agent.

[0022] As a further technical solution, the low-density polyethylene I, low-density polyethylene II and low-density polyethylene III are each independently one or more of Iran 2420H, Shell 2420H, Iran 2420D, Shell 2420D, Iran 2420F, Shell 2420F, Exxon LD150BW, Russia 15303, Dow 640I, and Iran Petrochemical 2100TN00.

[0023] As a further technical solution, the low-density polyethylene I, low-density polyethylene II and low-density polyethylene II are preferably Iran 2420H.

[0024] As a further technical solution, the linear low-density polyethylene with an anti-blocking agent includes one or more of Exxon 1001BU, Exxon 1002BU, Secco 0220KJ, Dow 2045.11G, Dow 2645.11G, and Borouge Chemical 1818.

[0025] As a further technical solution, the linear low-density polyethylene with an anti-blocking agent is preferably Dow 2045.11G.

[0026] As a further technical solution, the linear low-density polyethylene I and the linear low-density polyethylene II are independently one or more of Exxon 1001AV, Exxon 1002AY, Dow 2377, Secco 0209AA, Dow 2045G, Dow 2645G, Sinopec 7042, Prime 0134N, and Prime 0234N.

[0027] As a further technical solution, the linear low-density polyethylene I and the linear low-density polyethylene II are preferably Dow 2045G.

[0028] As a further technical solution, the foaming masterbatch is Kehui CFE-2130L.

[0029] As a further technical solution, the metallocene linear low-density polyethylene includes one or two of Mitsui SP1520 and Exxon 2012.

[0030] As a further technical solution, the metallocene linear low-density polyethylene is preferably Mitsui SP1520.

[0031] As a further technical solution, the high-density polyethylene includes one or more of Exxon HTA108, Exxon AL55-003, Sinopec 6098, Sinopec 6097, and Huizhou CNOOC / Shell B53-35H.

[0032] As a further technical solution, the high-density polyethylene is preferably Exxon HTA108.

[0033] As a further technical solution, the method for preparing the foamed PE film layer comprises the following steps:

[0034] A1. After the raw materials of layer A, layer B and layer C are mixed evenly, they are respectively put into a three-layer co-extrusion film blowing machine, and a foaming layer tubular object is formed at the die outlet;

[0035] A2. After the foamed tubular material is inflated, cooled, shaped, and surface treated, it is cut and rolled to obtain a foamed PE film layer.

[0036] As a further technical solution, the mass ratio of low-density polyethylene I to linear low-density polyethylene I in the A layer is 3:7.

[0037] As a further technical solution, the mass ratio of low-density polyethylene II, linear low-density polyethylene II, high-density polyethylene, and foaming masterbatch in the B layer is 30:45:20:5.

[0038] As a further technical solution, the mass ratio of low-density polyethylene III, metallocene linear low-density polyethylene, and linear low-density polyethylene with an anti-blocking agent in the C layer is 24:75:1.

[0039] As a further technical solution, the process parameters after the A layer raw material is put into the barrel of the three-layer co-extrusion blown film machine are as follows: the temperature of the groove barrel in the barrel is 145~155°C, the temperature of barrel zone 1 is 155~165°C, the temperature of barrel zone 2 is 165~175°C, the temperature of barrel zone 3 is 175~185°C, the temperature of barrel zone 4 is 175~185°C, and the temperatures of the screen changing zone and the flange zone are each independently 185~195°C.

[0040] As a further technical solution, the process parameters after the B layer raw material is put into the barrel of the three-layer co-extrusion film blowing machine are as follows: the temperature of the trough barrel in the barrel is 130~140°C, the temperature of barrel zone 1 is 135~145°C, the temperature of barrel zone 2 is 150~160°C, the temperature of barrel zone 3 is 155~165°C, the temperature of barrel zone 4 is 155~165°C, the temperatures of the screen changing zone and the flange zone are each independently 155~165°C, the B layer filter screen structure adopts 80 mesh + 300 mesh + 80 mesh, and the back pressure is 19.5~32.5MPa.

[0041] As a further technical solution, the process parameters after the C layer raw material is put into the barrel of the three-layer co-extrusion blown film machine are as follows: the temperature of the groove barrel in the barrel is 145~155°C, the temperature of barrel zone 1 is 155~165°C, the temperature of barrel zone 2 is 165~175°C, the temperature of barrel zone 3 is 175~185°C, the temperature of barrel zone 4 is 175~185°C, and the temperatures of the screen changing zone and the flange zone are each independently 185~195°C.

[0042] As a further technical solution, the interface base temperatures of the A layer, the B layer, and the C layer are all 195°C, and the die head temperatures are independently 155-165°C.

[0043] As a further technical solution, the inflation ratio during inflation in A2 is 2.5-3.0.

[0044] As a further technical solution, the cooling in A2 is performed by cooling air, and the temperature of the cooling air is 15-20°C.

[0045] As a further technical solution, the surface treatment in A2 is performed by using a corona treatment machine, and the power of the corona treatment machine is 400-500V.

[0046] As a further technical solution, the winding in A2 is carried out under the action of the winding reel tension of 70~90N on both sides.

[0047] As a further technical solution, the mass ratio of the thickness of layer A, layer B and layer C of the foamed PE film layer is 1:0.4~1.5:1.

[0048] The present invention also proposes a method for preparing a composite film bag with a foaming layer for facial mask packaging, comprising the following steps:

[0049] S1, printing the decorative layer film material to obtain a decorative layer;

[0050] S2, mixing the functional layer raw materials uniformly, melt-extruding, and then melt-casting to obtain the functional layer;

[0051] S3, in the order of the foamed PE film layer, the functional layer, and the decorative layer from bottom to top, hot pressing and laminating with an adhesive to obtain a composite film bag semi-finished product;

[0052] S4, sealing and cutting the composite film bag semi-finished product to obtain the composite film bag.

[0053] As a further technical solution, S1 is to place the decorative layer film material on the unwinding part of the printing press, flatten the decorative layer film material under an unwinding tension of 50~80N, an introduction tension of 130~170N, a lead-out tension of 100~150N, and a winding tension of 50~70N, and then print the alcohol-soluble polyamide system ink on the decorative layer film material according to the image and text through a metal gravure under a rubber roller pressure of 0.2~0.4MPa, and after drying in an oven at 40~60°C, roll it up to obtain the decorative layer.

[0054] As a further technical solution, the S3 is to first place the printed semi-finished product and the functional layer at the discharge position of the composite machine, and apply a specific gram weight (2.0~3.0g / square meter) adhesive to the decorative layer under the action of a first discharge tension of 80N~100N, a second discharge tension of 40N~60N, a drying tunnel tension of 90N~130N, and a winding tension of 140N~170N, and the coated film is placed in a 60~80℃ oven for drying. After drying, the decorative layer and the functional layer are thermally bonded at 45~55℃, and after bonding, they are cold treated and then rolled up to form a composite film semi-finished product I; then the composite film The semi-finished product I and the foamed PE film layer are placed at the unloading position of the laminating machine, and the foamed PE film layer is coated with an adhesive of specific gram weight (2.0-3.0 g / m2) under the action of a first unloading tension of 90N-110N, a second unloading tension of 40N-60N, a drying tunnel tension of 100N-130N, and a winding tension of 140N-170N. The coated film enters a 60-80°C oven for drying, and after drying, the composite film semi-finished product I and the foamed PE film layer are thermally bonded at 45-55°C. After bonding, the film is rolled up after cold treatment, and is cured, aired, and cut to obtain a composite film bag semi-finished product.

[0055] As a further technical solution, the curing temperature in S3 is 40-45° C., and the curing time is 24-48 hours.

[0056] As a further technical solution, the airing temperature in S3 is 15°C to 28°C.

[0057] As a further technical solution, the slitting in S3 is performed under an unwinding tension of 150N to 200N and a rewinding tension of 50N to 80N.

[0058] As a further technical solution, the sealing temperature in S4 is 130°C to 180°C, preferably 150°C.

[0059] As a further technical solution, when the composite film bag has a zipper, the sealing in S4 is performed by spot-heating using ultrasonic sealing technology; the ultrasonic power is 8W and the amplitude is 90%.

[0060] As a further technical solution, the slitting is performed using a cold knife, and the cooling temperature is 15°C to 25°C.

[0061] As a further technical solution, the thickness of the foamed PE film layer is 80 μm, the thickness of the functional layer is 20 μm, and the thickness of the decorative layer is 18 μm.

[0062] The working principle and beneficial effects of the present invention are:

[0063] The present invention provides a composite film bag for facial mask packaging with a foaming layer, which comprises, from bottom to top, a foamed PE film layer, a functional layer and a decorative layer, wherein the density of the foamed PE film layer is only 80% of that of an ordinary film layer. Under the same thickness, the packaging film of the present invention can reduce weight by 20%, thereby improving the utilization rate of the material. In addition, the unique concave-convex appearance of the foamed PE film layer makes the composite film bag present a granular roughness touch, thereby differentiating the appearance and touch from ordinary composite film bags, improving the product recognition and making it more attractive. A compatibilizer composed of an epoxy compound and polyvinyl alcohol is also added to the functional layer, which can improve the barrier properties and tensile strength of the composite film bag, thereby improving the quality and safety of the facial mask during storage and transportation. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0065] Figure 1 The structure of the composite film bag in Example 1 of the present invention;

[0066] In the figure: 1 is a decorative layer, 2 is an ink layer, 3 is an adhesive layer, 4 is a functional layer, and 5 is a foamed PE film layer;

[0067] Figure 2 This is a flow chart of the preparation process of the composite film bag in Example 1 of the present invention. DETAILED DESCRIPTION

[0068] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0069] In the following embodiments and comparative examples:

[0070] 545 PET: specific gravity 1.7g / cm 3 , DuPont, USA;

[0071] 408 NC010 PET: specific gravity 1.51g / cm 3 , DuPont, USA;

[0072] 0728 PET: specific gravity 1.2g / cm 3 , Dongguan Chuangzhihong Plastic Technology Co., Ltd.;

[0073] PEN: Model EN1099, Dongguan Ruida Plastic Technology Co., Ltd.;

[0074] Polyvinyl alcohol: Model 2488, Langfang Tianya Energy Saving Technology Co., Ltd.

[0075] Example 1

[0076] A method for preparing a composite film bag for facial mask packaging with a foaming layer comprises the following steps:

[0077] S1. Put the decorative layer PE film into the unwinding part of the printing machine, flatten the PE film under the conditions of unwinding tension of 50N, introduction tension of 130N, lead-out tension of 100N, and winding tension of 50N, and then print the alcohol-soluble polyamide system ink on the PE film according to the pattern under the pressure of the rubber roller of 0.2MPa through the metal gravure, dry it in an oven at 40°C, and then roll it up to obtain the decorative layer;

[0078] S2, 100 parts of 408 NC010 PET, 10 parts of PEN, 6 parts of compatibilizer, 10 parts of silicon dioxide, and 1 part of antioxidant 1010 are mixed evenly, melt-extruded to obtain a masterbatch, and the masterbatch is melt-casted to form a film to obtain a functional layer; wherein the compatibilizer is composed of γ-glycidyloxypropyltrimethoxysilane and polyvinyl alcohol in a mass ratio of 1:2;

[0079] S3, the raw materials of layer A are composed of Iranian 2420H and Dow 2045G in a mass ratio of 3:7; the raw materials of layer B are composed of Iranian 2420H, Dow 2045G, Exxon HTA108 and Kehui CFE-2130L in a mass ratio of 30:45:20:2; the raw materials of layer C are a mixture of Iranian 2420H, Mitsui SP1520 and Dow 2045.11G in a mass ratio of 24:75:1, and put them into the three barrels of the three-layer co-extrusion blown film machine;

[0080] Among them, the temperature of the groove barrel in the A layer barrel is 145℃, the temperature of barrel zone 1 is 155℃, the temperature of barrel zone 2 is 165℃, the temperature of barrel zone 3 is 175℃, the temperature of barrel zone 4 is 175℃, and the temperature of the screen changing zone and flange zone are both 185℃;

[0081] The temperature of the groove barrel in the B-layer barrel is 130℃, the temperature of barrel zone 1 is 135℃, the temperature of barrel zone 2 is 150℃, the temperature of barrel zone 3 is 155℃, the temperature of barrel zone 4 is 155℃, the temperature of the screen changing zone and flange zone is 155℃, the filter screen structure of the B-layer adopts 80 mesh + 300 mesh + 80 mesh, and the back pressure is 19.5MPa;

[0082] The temperature of the groove barrel in the C-layer barrel is 145°C, the temperature of barrel zone 1 is 155°C, the temperature of barrel zone 2 is 165°C, the temperature of barrel zone 3 is 175°C, the temperature of barrel zone 4 is 175°C, and the temperature of the screen changing zone and flange zone are both 185°C;

[0083] The interface base temperature of A, B and C layers is 195°C, and the die temperature is 155°C;

[0084] A foamed tubular object is formed at the die outlet; after the tubular object leaves the die, compressed gas is filled into the center hole of the die to inflate it into a bubble film with a blowing ratio of 2.5. The bubble film is cooled by the cooling air of the air ring with a temperature of 15°C. The position of the sizing cage is adjusted to shape the film bubble;

[0085] After cooling and shaping, the film is regulated by the thickness automatic control system according to the set film thickness, then pulled up by the traction device and flattened by the herringbone plate, and then clamped by a traction roller to form a double-layer film, and the outer surface of the film is corona treated by the corona device. The power of the corona machine is 400V;

[0086] Finally, the film is cut and split into pieces according to the set width by the cutting and winding device, and wound up under the action of the tension (70N) of the winding reels on both sides to obtain a foamed PE film layer (the thickness ratio of the A layer, the B layer, and the C layer is 1:0.4:1);

[0087] S4. Place the decorative layer and the functional layer at the discharge position of the laminating machine in the order of foamed PE film layer, functional layer and decorative layer from bottom to top. Apply adhesive of specific gram weight (2.0g / m2) to the decorative layer under the action of first discharge tension of 80N, second discharge tension of 40N, drying tunnel tension of 90N and winding tension of 140N. The coated film is placed in a 60℃ oven for drying. After drying, the decorative layer and the functional layer are thermally bonded at 45℃. After bonding, they are rolled up after cold treatment to form a composite. Film semi-finished product I; then the composite film semi-finished product I and the foamed PE film layer are placed at the discharge position of the laminating machine, and the foamed PE film layer is coated with a specific gram weight (2.0g / square meter) adhesive under the action of the first discharge tension of 90N, the second discharge tension of 40N, the drying tunnel tension of 100N, and the winding tension of 140N. The coated film is placed in a 60°C oven for drying. After drying, the composite film semi-finished product I and the foamed PE film layer are thermally bonded at 45°C. After bonding, they are rolled up after cold treatment to obtain a composite film bag semi-finished product;

[0088] S5. Place the semi-finished composite film bag after heat bonding in a drying room at 40°C to cure the adhesive within 48 hours;

[0089] S6. Air-drying: The semi-finished composite film bag after curing is placed in the air-drying area in an environment of 15°C for stress release and cooling and shaping;

[0090] S7, slitting: the semi-finished composite film bag after airing is placed at the feeding position of the slitting machine, and the semi-finished composite film bag is flattened under the action of the unwinding tension of 150N and the rewinding tension of 50N, and the composite film is cut into sub-rolls of fixed specifications according to the size of the layout design using a cutter;

[0091] S8, bag making: The matured composite film bag semi-finished product can be cut according to S7. The composite film bag semi-finished product is folded and formed by the guide roller. After forming, it is sealed by a high-temperature hot knife. The sealing temperature is 130°C. After sealing, a cold knife (temperature 15°C) is used to cool and shape the sealing area. Finally, a cutting knife is used to cut to obtain a composite film bag (the thickness of the foamed PE film layer is 80μm, the thickness of the functional layer is 20μm, and the thickness of the decorative layer is 18μm). The structure of the composite film bag is as follows Figure 1 As shown, the preparation process flow chart of the composite film bag is as follows Figure 2 shown.

[0092] Example 2

[0093] A method for preparing a composite film bag for facial mask packaging with a foaming layer comprises the following steps:

[0094] S1. Put the decorative layer PE film into the unwinding part of the printing machine, flatten the PE film under the conditions of unwinding tension of 60N, introduction tension of 140N, lead-out tension of 120N, and rewinding tension of 60N, and then print the alcohol-soluble polyamide system ink on the PE film according to the image and text through the metal gravure under the pressure of the rubber roller of 0.3MPa, dry it in an oven at 50°C, and rewind it to obtain the printed semi-finished product;

[0095] S2, 100 parts of 408 NC010 PET, 15 parts of PEN, 7 parts of compatibilizer, 11 parts of montmorillonite, and 1.2 parts of antioxidant 168 were mixed evenly, and melt-extruded to obtain a masterbatch, and the masterbatch was melt-casted to form a film to obtain a functional layer; wherein the compatibilizer was composed of γ-glycidyloxypropyltrimethoxysilane and polyvinyl alcohol in a mass ratio of 1:2;

[0096] S3, the raw materials of layer A are composed of Iranian 2420H and Dow 2045G in a mass ratio of 3:7; the raw materials of layer B are composed of Iranian 2420H, Dow 2045G, Exxon HTA108 and Kehui CFE-2130L in a mass ratio of 30:45:20:2; the raw materials of layer C are a mixture of Iranian 2420H, Mitsui SP1520 and Dow 2045.11G in a mass ratio of 24:75:1, and put them into the three barrels of the three-layer co-extrusion blown film machine;

[0097] Among them, the temperature of the groove barrel in the A layer barrel is 150℃, the temperature of barrel zone 1 is 160℃, the temperature of barrel zone 2 is 170℃, the temperature of barrel zone 3 is 180℃, the temperature of barrel zone 4 is 180℃, and the temperature of the screen changing zone and flange zone are both 190℃;

[0098] The temperature of the groove barrel in the B-layer barrel is 135°C, the temperature of barrel zone 1 is 140°C, the temperature of barrel zone 2 is 155°C, the temperature of barrel zone 3 is 160°C, the temperature of barrel zone 4 is 160°C, the temperature of the screen changing zone and flange zone is 160°C, the filter screen structure of the B-layer adopts 80 mesh + 300 mesh + 80 mesh, and the back pressure is 20.5MPa;

[0099] The temperature of the groove barrel in the C-layer barrel is 150°C, the temperature of barrel zone 1 is 160°C, the temperature of barrel zone 2 is 170°C, the temperature of barrel zone 3 is 170°C, the temperature of barrel zone 4 is 180°C, and the temperature of the screen changing zone and flange zone are both 190°C;

[0100] The interface base temperature of A, B and C layers is 195°C, and the die temperature is 160°C;

[0101] A foamed tubular object is formed at the die outlet; after the tubular object leaves the die, compressed gas is filled into the center hole of the die to inflate it into a bubble film with a blowing ratio of 2.8. The bubble film is cooled by the cooling air of the air ring with a temperature of 18°C. The position of the sizing cage is adjusted to shape the film bubble;

[0102] After cooling and shaping, the film is regulated by the thickness automatic control system according to the set film thickness, then pulled up by the traction device and flattened by the herringbone plate, and then clamped by a traction roller to form a double-layer film, and the outer surface of the film is corona treated by the corona device. The power of the corona machine is: 450V;

[0103] Finally, the film is cut and split into pieces according to the set width by the cutting and winding device, and wound up under the action of the winding reel tension (80N) on both sides to obtain a foamed PE film layer (the thickness ratio of the A layer, the B layer, and the C layer is 1:1:1);

[0104] S4. Place the decorative layer and the functional layer at the discharge position of the laminating machine in the order of foamed PE film layer, functional layer and decorative layer from bottom to top. Apply adhesive of specific weight (2.5g / m2) to the decorative layer under the action of first discharge tension of 90N, second discharge tension of 50N, drying tunnel tension of 100N and winding tension of 150N. The coated film is put into a 70℃ oven for drying. After drying, the decorative layer and the functional layer are thermally bonded at 50℃. After bonding, they are rolled up after cold treatment to form a composite. Film semi-finished product I; then the composite film semi-finished product I and the foamed PE film layer are placed at the discharge position of the laminating machine, and the foamed PE film layer is coated with a specific gram weight (2.5g / square meter) adhesive under the action of the first discharge tension of 100N, the second discharge tension of 50N, the drying tunnel tension of 120N, and the winding tension of 160N. The coated film is placed in a 70°C oven for drying. After drying, the composite film semi-finished product I and the foamed PE film layer are thermally bonded at 50°C. After bonding, they are rolled up after cold treatment to obtain a composite film bag semi-finished product;

[0105] S5. Place the semi-finished composite film bag after heat bonding in a drying room at 42°C to cure the adhesive within 30 hours;

[0106] S6. Air-drying: The semi-finished composite film bag after curing is placed in the air-drying area in an environment of 20°C for stress release and cooling and shaping;

[0107] S7, slitting: the semi-finished composite film bag after airing is placed at the feeding position of the slitting machine, and the semi-finished composite film bag is flattened under the action of the unwinding tension of 180N and the rewinding tension of 70N, and the composite film is cut into sub-rolls of fixed specifications according to the size of the layout design using a cutter;

[0108] S8, bag making: the matured semi-finished composite film bag can be optionally cut according to S7, the semi-finished composite film bag is folded and formed by the guide roller, and is sealed by a high-temperature hot knife after forming, the sealing temperature is 150°C, after sealing, a cold knife (temperature 20°C) is used to cool and shape the sealing area, and finally a cutting knife is used to cut to obtain a composite film bag (the thickness of the foamed PE film layer is 80μm, the thickness of the functional layer is 20μm, and the thickness of the decorative layer is 18μm).

[0109] Example 3

[0110] A method for preparing a composite film bag for facial mask packaging with a foaming layer comprises the following steps:

[0111] S1. Put the decorative layer PE film into the unwinding part of the printing machine, flatten the PE film under the conditions of unwinding tension of 80N, introduction tension of 170N, lead-out tension of 150N, and winding tension of 70N, and then print the alcohol-soluble polyamide system ink on the PE film according to the pattern under the pressure of 0.4MPa rubber roller through the metal gravure, dry it in an oven at 60°C, and then roll it up to obtain the decorative layer;

[0112] S2, 100 parts of 408 NC010 PET, 20 parts of PEN, 8 parts of compatibilizer, 12 parts of mica, and 1.5 parts of antioxidant 1076 were mixed evenly, and melt-extruded to obtain a masterbatch, and the masterbatch was melt-casted to form a film to obtain a functional layer; wherein the compatibilizer was composed of γ-glycidyloxypropyltrimethoxysilane and polyvinyl alcohol in a mass ratio of 1:2;

[0113] S3, the raw materials of layer A are composed of Iranian 2420H and Dow 2045G in a mass ratio of 3:7; the raw materials of layer B are composed of Iranian 2420H, Dow 2045G, Exxon HTA108 and Kehui CFE-2130L in a mass ratio of 30:45:20:2; the raw materials of layer C are a mixture of Iranian 2420H, Mitsui SP1520 and Dow 2045.11G in a mass ratio of 24:75:1, and put them into the three barrels of the three-layer co-extrusion blown film machine;

[0114] Among them, the temperature of the groove barrel in the A layer barrel is 150℃, the temperature of barrel zone 1 is 165℃, the temperature of barrel zone 2 is 175℃, the temperature of barrel zone 3 is 185℃, the temperature of barrel zone 4 is 185℃, and the temperature of the screen changing zone and flange zone are both 195℃;

[0115] The temperature of the groove barrel in the B-layer barrel is 140°C, the temperature of barrel zone 1 is 145°C, the temperature of barrel zone 2 is 160°C, the temperature of barrel zone 3 is 165°C, the temperature of barrel zone 4 is 165°C, the temperature of the screen changing zone and flange zone is 165°C, the filter screen structure of the B-layer adopts 80 mesh + 300 mesh + 80 mesh, and the back pressure is 32.5MPa;

[0116] The temperature of the groove barrel in the C-layer barrel is 155°C, the temperature of barrel zone 1 is 165°C, the temperature of barrel zone 2 is 175°C, the temperature of barrel zone 3 is 185°C, the temperature of barrel zone 4 is 185°C, and the temperature of the screen changing zone and flange zone are both 195°C;

[0117] The interface base temperature of A, B and C layers is 195°C, and the die temperature is 165°C;

[0118] A foamed tubular object is formed at the die outlet; after the tubular object leaves the die, compressed gas is filled into the center hole of the die to inflate it into a bubble film with a blowing ratio of 3.0. The bubble film is cooled by the cooling air of the air ring with a temperature of 20°C. The position of the sizing cage is adjusted to shape the film bubble;

[0119] After cooling and shaping, the film is regulated by the thickness automatic control system according to the set film thickness, then pulled up by the traction device and flattened by the herringbone plate, and then clamped by a traction roller to form a double-layer film, and the outer surface of the film is corona treated by the corona device. The power of the corona machine is 500V;

[0120] Finally, the film is cut and split into pieces according to the set width by the cutting and winding device, and wound up under the action of the tension (90N) of the winding reels on both sides to obtain a foamed PE film layer (the thickness ratio of the A layer, the B layer, and the C layer is 1:1.5:1);

[0121] S4. Place the decorative layer and the functional layer at the discharge position of the laminating machine in the order of foamed PE film layer, functional layer and decorative layer from bottom to top. Apply adhesive of specific weight (3.0g / m2) to the decorative layer under the action of first discharge tension of 100N, second discharge tension of 60N, drying tunnel tension of 130N and winding tension of 170N. The coated film is placed in an oven at 80℃ for drying. After drying, the decorative layer and the functional layer are thermally bonded at 55℃. After bonding, they are rolled up after cold treatment to form a composite. Film semi-finished product I; then the composite film semi-finished product I and the foamed PE film layer are placed at the discharge position of the laminating machine, and the foamed PE film layer is coated with a specific gram weight (3.0g / square meter) adhesive under the action of the first discharge tension of 110N, the second discharge tension of 60N, the drying tunnel tension of 130N, and the winding tension of 170N. The coated film is placed in an 80°C oven for drying. After drying, the composite film semi-finished product I and the foamed PE film layer are thermally bonded at 55°C. After bonding, they are rolled up after cold treatment to obtain a composite film bag semi-finished product;

[0122] S5. Place the semi-finished composite film bag after heat bonding in a drying room at 45°C to cure the adhesive within 24 hours;

[0123] S6. Air-drying: The semi-finished composite film bag after curing is placed in the air-drying area in an environment of 28°C for stress release and cooling and shaping;

[0124] S7, slitting: the semi-finished composite film bag after airing is placed at the feeding position of the slitting machine, and the semi-finished composite film bag is flattened under the action of unwinding tension of 200N and winding tension of 80N, and the composite film is cut into sub-rolls of fixed specifications according to the size of the layout design using a cutter;

[0125] S8, bag making: The matured composite film bag semi-finished product can be cut according to S7. The composite film bag semi-finished product is folded and formed by the guide roller. After forming, it is sealed by a high-temperature hot knife at a sealing temperature of 180°C. After sealing, a cold knife (temperature 25°C) is used to cool and shape the sealing area, and finally a cutting knife is used to cut to obtain a composite film bag (the thickness of the foamed PE film layer is 80μm, the thickness of the functional layer is 20μm, and the thickness of the decorative layer is 18μm).

[0126] Example 4

[0127] The only difference between this embodiment and embodiment 1 is that the compatibilizer consists of 3-[(phenylmethyl)amino]-3-oxetanemethylamine and polyvinyl alcohol in a mass ratio of 1:2.

[0128] Example 5

[0129] The difference between this embodiment and embodiment 1 is that the compatibilizer consists of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol in a mass ratio of 1:2.

[0130] Example 6

[0131] The difference between this embodiment and embodiment 5 is that the compatibilizer consists of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol in a mass ratio of 5:1.

[0132] Example 7

[0133] The difference between this embodiment and embodiment 5 is that the compatibilizer consists of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol in a mass ratio of 2:1.

[0134] Example 8

[0135] The only difference between this embodiment and embodiment 5 is that the compatibilizer consists of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol in a mass ratio of 3:1.

[0136] Example 9

[0137] The difference between this embodiment and embodiment 5 is that the compatibilizer consists of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol in a mass ratio of 4:1.

[0138] Example 10

[0139] The only difference between this embodiment and embodiment 1 is that 408 NC010 PET is replaced by an equal amount of 545 PET.

[0140] Embodiment 11

[0141] The only difference between this embodiment and embodiment 1 is that 408 NC010 PET is replaced with an equal amount of 0728 PET.

[0142] Example 12

[0143] The only difference between this embodiment and embodiment 1 is that 408 NC010 PET is replaced by 545 PET and 408 NC010 PET in a mass ratio of 3:1.

[0144] Embodiment 13

[0145] The only difference between this embodiment and embodiment 1 is that 408 NC010 PET is replaced by 545 PET and 0728 PET with a mass ratio of 3:1.

[0146] Embodiment 14

[0147] The only difference between this embodiment and embodiment 1 is that 408 NC010 PET is replaced by 408 NC010 PET and 0728 PET in a mass ratio of 3:1.

[0148] Comparative Example 1

[0149] The only difference between this comparative example and Example 1 is that the compatibilizer is γ-glycidyloxypropyltrimethoxysilane.

[0150] Comparative Example 2

[0151] The only difference between this comparative example and Example 1 is that the compatibilizer is polyvinyl alcohol.

[0152] Test Example 1

[0153] The composite film bags in Examples 1 to 14 and Comparative Examples 1 to 2 were tested for oxygen permeability and water vapor permeability according to the test method in GB / T 10004-2008 "Plastic composite films and bags for packaging, dry composite, extrusion composite", wherein the test conditions for water vapor permeability are: 38°C, 90%RH; the test conditions for oxygen permeability are: 23°C, 0%RH, and the test results are shown in Table 1.

[0154] Table 1 Performance measurement results of the composite film bag functional layer in Examples 1 to 14 and Comparative Examples 1 to 2

[0155]

[0156] Compared with Example 1, the compatibilizer in Comparative Example 1 is only γ-glycidyloxypropyltrimethoxysilane, and the compatibilizer in Comparative Example 2 is polyvinyl alcohol. As a result, the oxygen permeability and water vapor permeability in Comparative Examples 1~2 are both greater than those in Example 1, indicating that the compatibilizer composed of γ-glycidyloxypropyltrimethoxysilane and polyvinyl alcohol can improve the barrier properties of the composite film bag to oxygen and water vapor.

[0157] Compared with Example 1, Examples 4 and 5 were replaced with other epoxy compounds respectively. As a result, the oxygen permeability and water vapor permeability of Example 5 were lower than those of Example 1 and Example 4, indicating that the compatibilizer composed of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol can further improve the barrier properties of the composite film bag to oxygen and water vapor.

[0158] Compared with Example 5, Examples 6 to 9 change the ratio of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol. As a result, the oxygen permeability and water vapor permeability of Examples 7 to 9 are lower than those of Examples 5 and 6, indicating that when the mass ratio of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol is 2 to 4:1, the barrier property of the composite film bag to oxygen and water vapor can be further improved.

[0159] Compared with Example 1, Examples 10 to 14 were replaced with PET of different densities, respectively. As a result, the oxygen permeability and water vapor permeability of Example 14 were lower than those of Example 1 and Examples 10 to 13, indicating that when PET is composed of 408 NC010 PET and 0728 PET, the barrier properties of the composite film bag to oxygen and water vapor can be further improved.

[0160] Test Example 2

[0161] The tensile strength of the functional layer in the composite film bag in Examples 1, 4-5, 10-14 and Comparative Examples 1-2 was measured according to the measurement method in GB / T1040.1-2018 "Determination of Tensile Properties of Plastics Part 1: General Principles", and the measurement results are shown in Table 2.

[0162] Table 2 Performance test results of composite film bags in Examples 1, 4-5, 10-14 and Comparative Examples 1-2

[0163]

[0164] Compared with Comparative Examples 1 and 2, Examples 1, 4 and 5 change the composition of the compatibilizer. As a result, the tensile strength in Example 5 is higher than that in Examples 1 and 4 and Comparative Examples 1 and 2, indicating that the compatibilizer is composed of 4-(oxiranylmethoxy)benzeneacetamide and polyvinyl alcohol, which can improve the tensile strength of the functional layer.

[0165] Compared with Example 1, Examples 10 to 14 changed the density and composition of the PET material. As a result, the tensile strength in Example 14 was higher than that in Example 1 and Examples 10 to 13, indicating that when PET is composed of 408 NC010 PET and 0728 PET, the tensile strength of the functional layer can be further improved.

[0166] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A composite film bag for facial mask packaging with a foaming layer, characterized in that: The composite film bag comprises a foamed PE film layer, a functional layer and a decorative layer from bottom to top; the functional layer comprises the following raw materials by weight: 100 parts of PET, 10-20 parts of PEN, 6-8 parts of a compatibilizer, 10-12 parts of a filler, and 1-1.5 parts of an antioxidant; the compatibilizer is composed of an epoxy compound and polyvinyl alcohol; The epoxy compound includes one or more of γ-glycidyloxypropyltrimethoxysilane, 3-[(phenylmethyl)amino]-3-oxetanemethylamine, and 4-(oxiranylmethoxy)phenylacetamide; The mass ratio of the epoxy compound to the polyvinyl alcohol is 2-4:1; The foamed PE film layers are layer A, layer B, and layer C from bottom to top; The A layer comprises raw materials of the following components: low-density polyethylene I, linear low-density polyethylene I; The B layer includes the following raw materials: low-density polyethylene II, linear low-density polyethylene II, high-density polyethylene, and foaming masterbatch; The C layer comprises the following raw materials: low-density polyethylene III, metallocene linear low-density polyethylene, and linear low-density polyethylene with an anti-blocking agent.

2. The composite film bag for facial mask packaging with a foaming layer according to claim 1, characterized in that: The density of the PET is 1.20-1.70 g / cm 3 .

3. The composite film bag for facial mask packaging with a foaming layer according to claim 2, characterized in that: The PET consists of a first PET and a second PET, and the first PET and the second PET have different densities.

4. The composite film bag for facial mask packaging with a foaming layer according to claim 1, characterized in that: The mass ratio of low-density polyethylene I to linear low-density polyethylene I in the A layer is 3:

7.

5. The composite film bag with a foaming layer for facial mask packaging according to claim 1, characterized in that: The mass ratio of low-density polyethylene II, linear low-density polyethylene II, high-density polyethylene and foaming masterbatch in the B layer is 30:45:20:

5.

6. The composite film bag with a foaming layer for facial mask packaging according to claim 1, characterized in that: The method for preparing the foamed PE film layer comprises the following steps: A1. After the raw materials of layer A, layer B and layer C are mixed evenly, they are respectively put into a three-layer co-extrusion film blowing machine, and a foaming layer tubular object is formed at the die outlet; A2. After the foamed tubular material is inflated, cooled, shaped, and surface treated, it is cut and rolled to obtain a foamed PE film layer.

7. The method for preparing a composite film bag for facial mask packaging with a foaming layer according to any one of claims 1 to 6, characterized in that: The following steps are involved: S1, printing the decorative layer film material to obtain a decorative layer; S2, mixing the functional layer raw materials uniformly, melt-extruding, and then melt-casting to obtain the functional layer; S3, in the order of the foamed PE film layer, the functional layer, and the decorative layer from bottom to top, hot pressing and laminating with an adhesive to obtain a composite film bag semi-finished product; S4, sealing and cutting the composite film bag semi-finished product to obtain the composite film bag.

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