Packaging bag structure with three layers of transparent films

Abstract

The utility model provides a packaging bag structure with three layers of transparent films, which comprises a printing layer, an ink layer, a first adhesive layer, a PET (polyethylene terephthalate) film layer, a second adhesive layer and a polyethylene heat sealing layer which are sequentially arranged from outside to inside, the thickness of the ink layer is 2 microns, the ink layer is printed on the OPP film printing layer through an intaglio printing process, and the thickness of the first adhesive layer is 2 microns. The ink layer is white solvent type ink with high solid content, and the depth of the white ink printing plate is 30 microns; according to the utility model, the use of a solvent is reduced by reducing the plate depth during printing of the ink layer, so that the problem of excessive emission of VOCs can be solved, and in order to avoid the problem that the covering power of white ink is reduced due to the reduction of the plate depth, a mode of increasing the proportion of titanium dioxide is adopted, so that the printing effect is not influenced; the purposes of small packaging bag pollution and good printing effect are achieved.

Description

Technical Field

[0001] The utility model relates to the technical field of transparent packaging bag design, in particular to a packaging bag structure with three layers of transparent films. Background Art

[0002] In modern society, my country's air pollution and haze situation is becoming increasingly severe. With the improvement of environmental awareness, people are paying more and more attention to the impact of the production process on the environment. Among them, printing and laminating processes in the flexible packaging industry are relatively large sources of pollution. my country has promulgated the GB38507-2020 standard for the management of printing inks. In the printing industry, the use of solvent-based inks used in gravure printing processes is indispensable, and the solvent content in the ink directly affects the emission of volatile organic compounds (VOCs) during the printing process. The solvent content of the commonly used inks in the existing process accounts for a high proportion, and the resulting impacts are high solvent costs and high solvent VOCs emissions during printing operations, resulting in worse overall environmental protection effects and higher investment costs.

[0003] In the existing packaging bag process, reducing VOCs emissions is usually done by reducing the proportion of organic solvents in the ink and adding an appropriate amount of hyperdispersant additives to solve the negative impact of reducing the proportion of organic solvents (the solvent is reduced, the ink fluidity deteriorates, affecting the printing effect), but this solution inevitably affects the printing effect. In the subsequent finished product composite process, we often use a solvent-based composite process, which will apply a large amount of solvents, which brings huge VOCs emissions. And the problem of ink transfer or low interlayer strength often occurs due to the mismatch between the thickness of the ink layer and the adhesive layer. Utility Model Content

[0004] The utility model provides a packaging bag structure with three layers of transparent films to solve the problems of high proportion of organic solvents and large VOCs emissions caused by the thickness of the ink layer of the existing packaging bags mentioned in the background technology.

[0005] The technical solution of the utility model is achieved in this way:

[0006] A three-layer transparent film packaging bag structure comprises a printing layer, an ink layer, a first adhesive layer, a PET film layer, a second adhesive layer and a polyethylene heat-sealing layer which are sequentially arranged from the outside to the inside, wherein the ink layer has a thickness of 2 μm and is printed on the OPP film printing layer by a gravure printing process, the ink layer is a high-solid white solvent-based ink, and the plate depth of the white ink printing plate is 30 μm.

[0007] Preferably, the printing layer is made of OPP film.

[0008] Preferably, the printing layer has a thickness of 19 μm.

[0009] Preferably, the thickness of the first adhesive layer and the second adhesive layer are both 2 μm.

[0010] Preferably, the thickness of the PET film layer is 12 μm.

[0011] Preferably, the thickness of the polyethylene heat-sealing layer is 60 μm.

[0012] By adopting the above technical solution, the beneficial effects of the utility model are as follows:

[0013] The utility model reduces the use of solvents by reducing the plate depth thickness during printing of the ink layer, thereby solving the problem of excessive emission of VOCs. In addition, in order to avoid the problem of decreased covering power of white ink due to reduced plate depth thickness, the printing effect is not affected by increasing the proportion of titanium dioxide, thereby achieving the purpose of less pollution to the packaging bag and good printing effect. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] In order to more clearly illustrate the embodiments of the utility model or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0015] Figure 1 It is a structural schematic diagram of the utility model.

[0016] in:

[0017] 1. Printing layer; 2. Ink layer; 3. First adhesive layer; 4. PET film layer; 5. Second adhesive layer; 6. Polyethylene heat sealing layer. DETAILED DESCRIPTION

[0018] The following will be combined with the drawings in the embodiments of the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. Obviously, the described embodiments are only part of the embodiments of the utility model, not all of the embodiments. Based on the embodiments of the utility model, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the utility model.

[0019] As shown in the figure, a three-layer transparent film packaging bag structure includes a printing layer 1, an ink layer 2, a first adhesive layer 3, a PET film layer 4, a second adhesive layer 5 and a polyethylene heat-sealing layer 6 which are arranged in sequence from the outside to the inside, wherein the printing layer 1 is made of OPP film material with a thickness of 19 μm.

[0020] The ink layer 2 has a thickness of 2 μm, and the ink layer 2 is printed on the OPP film substrate layer 1 by gravure printing. The ink layer 2 is a high-solid white solvent-based ink, and the plate depth of the white ink printing plate is 30 μm. This setting is mainly to reduce the wet ink volume of the white ink by reducing the plate depth of the white ink printing plate, thereby reducing the proportion of solvent therein, so as to achieve the purpose of reducing VOCs emissions; in addition, considering that the reduction in plate depth reduces the covering power of the white ink, the proportion of titanium dioxide in the ink ratio is increased, so that the overall printing effect is not affected. In addition, this packaging bag structure that reduces the use of solvents can also alleviate the storage capital investment and safety hazards caused by the presence of a large amount of solvents.

[0021] The following table shows the solvent usage per unit area and the ink hiding power under different plate depths (50μm and 30μm):

[0022] Depth Solvent usage per square meter Ink hiding power Original white ink process 50μ 4.2g / ㎡ 55 High solid white ink process 30μ 2.5g / ㎡ 62

[0023] The following table gives the raw material ratio under different plate depths (50μm and 30μm):

[0024]

[0025] Specifically, the thickness of the first adhesive layer 3 and the second adhesive layer 5 are both 2 μm; the thickness of the PET film layer 4 is 12 μm; and the thickness of the polyethylene heat-sealing layer 6 is 60 μm.

[0026] The process flow of this three-layer transparent film packaging bag is printing-dry lamination-slitting / bag making. Compared with the traditional solution, this solution does not affect the overall printing effect by adjusting the ratio of the printing plate and the ink itself, and reduces the overall solvent input to achieve the purpose of reducing the VOC content. In the compounding process, a solvent-free compounding process is adopted. Its process characteristics are that it does not require ethyl ester solvent dilution and can be directly operated by a compounding machine, which greatly reduces the use of solvents and reduces the generation of VOCs in this link. In addition, through adjustments in the printing process, the thickness of the ink layer is reduced, so that the bonding strength between the first adhesive layer and the ink layer is improved. After the compounding process is completed, it is aged in a curing room (45°C, 48h), and then enters the slitting or bag making process for production.

[0027] The above description is only a preferred embodiment of the present invention and is 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 packaging bag structure with three layers of transparent film, characterized in that: It includes a printing layer, an ink layer, a first adhesive layer, a PET film layer, a second adhesive layer and a polyethylene heat-sealing layer which are arranged in sequence from the outside to the inside. The ink layer has a thickness of 2 μm and is printed on the OPP film printing layer by a gravure printing process. The ink layer is a high-solid white solvent-based ink, and the plate depth of the white ink printing plate is 30 μm.

2. The packaging bag structure of a three-layer transparent film according to claim 1, characterized in that: The printing layer is made of OPP film.

3. The packaging bag structure of a three-layer transparent film according to claim 1, characterized in that: The thickness of the printing layer is 19 μm.

4. The packaging bag structure of a three-layer transparent film according to claim 1, characterized in that: The thickness of the first adhesive layer and the second adhesive layer are both 2 μm.

5. The packaging bag structure of a three-layer transparent film according to claim 1, characterized in that: The thickness of the PET film layer is 12 μm.

6. The packaging bag structure of a three-layer transparent film according to claim 1, characterized in that: The thickness of the polyethylene heat-sealing layer is 60 μm.

Images