CN111471284A

CN111471284A - Production process of degradable environment-friendly plastic product

Info

Publication number: CN111471284A
Application number: CN202010333079.5A
Authority: CN
Inventors: 雷明成
Original assignee: Chongqing Jialei Printing Co ltd
Current assignee: Chongqing Jialei Printing Co ltd
Priority date: 2020-04-24
Filing date: 2020-04-24
Publication date: 2020-07-31

Abstract

The invention relates to the field of environment-friendly plastic processing, and particularly discloses a production process of a degradable environment-friendly plastic product, which adopts a raw material preparation step, wherein the raw material preparation step comprises 10-20 parts by mass of P L A, 60-80 parts by mass of PBAT, 1-3 parts by mass of a slipping agent and 0.5-1.5 parts by mass of a shedding agent, so that the formed tissue packaging paper has a natural degradation function, a film blowing machine and a printing machine are simultaneously prepared, the raw material is processed into a crude film by the film blowing machine in the step 2, the tension of the crude film is controlled to be 10-17N, the thickness of the crude film is 2.5-9 mu m, then the crude film is processed into a single-layer film in the steps 3 and 4, and then the single-layer film is subjected to pattern printing processing.

Description

Production process of degradable environment-friendly plastic product

Technical Field

The invention belongs to the field of processing of environment-friendly plastics, and particularly relates to a production process of a degradable environment-friendly plastic product.

Background

Plastic bags have been integrated into people's daily life, but because the conventional PE plastic has the characteristic of being not easily degraded by natural microorganisms, "white pollution" caused by plastic bags is more and more serious, so that the degradable technology of plastics at present is one of the important directions for the development of plastic bags.

In order to enable a plastic bag to achieve a degradable effect, the plastic raw material is replaced by PE plastic raw material for P L A, BPIT, PHAs, PBA, PBS and other high polymer materials, the produced environment-friendly plastic bag is mostly applied to the manufacturing of packages such as supermarket shopping bags, continuous rolling freshness protection bags and the like, the environment-friendly plastic bag is limited by processing raw materials and processing technology, the stiffness and the stretch resistance of materials of the supermarket shopping bags and the continuous rolling freshness protection bags are low, when large patterns are printed on the supermarket shopping bags and the continuous rolling freshness protection bags, the situations of pattern missing printing, dislocation printing and the like easily occur on the supermarket shopping bags and the continuous rolling freshness protection bags, the overprinting precision can reach 1cm seriously, if the processing raw materials and the processing technology of the supermarket shopping bags or the continuous rolling freshness protection bags are applied to the packaging bags of tissues, the patterns such as large figures, cartoons, commodity bar codes and the like on the packaging bags of the tissues cannot be completely printed, the attractiveness of the packaging bags of the tissues can be directly influenced, and the normal selling of the tissues is difficult.

Disclosure of Invention

The invention aims to provide a production process of a degradable environment-friendly plastic product, and aims to solve the problem of serious printing defects of identification information such as patterns, bar codes and the like on a degradable paper towel packaging bag.

In order to achieve the above object, the basic scheme of the invention is as follows: a production process of a degradable environment-friendly plastic product comprises the following steps:

step 1, preparing the following raw materials, namely 10-20 parts of P L A, 60-80 parts of PBAT, 1-3 parts of a slipping agent and 0.5-1.5 parts of an opening agent in parts by mass, and simultaneously preparing a film blowing machine and a printing machine;

step 2: placing the raw materials into each material storage barrel of a film blowing machine, after the film blowing machine sucks the raw materials, carrying out hot melting on the raw materials at the hot melting temperature of 120-170 ℃, and then blowing the melted raw materials into a cylindrical crude film, wherein the tension of the crude film is controlled to be 10-17N, and the thickness of the crude film is 2.5-9 mu m;

and step 3: carrying out edge cutting and winding processing on the crude film in the step 2, and cutting the crude film into a single-layer film;

and 4, step 4: the single-layer film is arranged on a feeding roller of a printer, the printer performs pattern printing on the surface of the single-layer film, and the overprinting precision is less than or equal to 0.5 mm.

The principle of the basic scheme and the advantages thereof are that 10-20 parts of P L A biodegradable material is adopted in raw materials, the thickness of a crude film is controlled to be 2.5-9 mu m, the tension of the finally processed single-layer film is controlled to be 10-17N, the stiffness of the single-layer film is effectively improved compared with that of the existing degradable supermarket shopping bags and continuous rolling freshness protection bags, and the processed single-layer film has the characteristics of lightness, good tensile resistance and water resistance after the raw material components and the corresponding hot melting temperature are adopted, so that the paper towel packaging bag is suitable for being used for manufacturing paper towel packaging bags.

After the thickness and the tension of control individual layer membrane, when placing the individual layer membrane on the printing machine again, individual layer membrane can be by stable and smooth tensioning print processing on the printing machine, because the deflection of individual layer membrane is good, can not produce the fold at the in-process of carrying out the printing, the condition such as deformation, can ensure that the clear printing of the large sheet pattern of polychrome is to individual layer membrane on the surface, pattern after the printing, identification information such as bar code can show completely, and then make overprinting precision less than or equal to 0.5mm, reach accurate printing, can effectively overcome the printing defect that supermarket shopping bag and continuous roll freshness protection package exist, ensure that the paper handkerchief when sweeping the sign indicating number settlement, can not make mistakes.

Meanwhile, the paper towel packaging bag made of the raw materials contains 10-20 parts of P L A biodegradable materials, so that the packaging bag can be degraded to generate carbon dioxide and water after composting for about 180 days after use, and has good environmental protection characteristic.

Further, in step 1, be equipped with a plurality of cold air pipes and the flow controller of the even air inlet of a plurality of cold air pipes of control on the inflation film manufacturing machine, in step 2, the one end of cold air pipe air-out is relative with the lateral wall of crude product membrane, and the one end of a plurality of cold air pipe air-out is evenly relative with global of crude product membrane.

A plurality of cold wind pipes are evenly relative with global of crude product membrane, when cold wind pipe blowout cold wind, can let the crude product membrane that finally forms keep smooth and smooth state to the even cooling in side of crude product membrane, and let the thickness of crude product membrane keep even state, promote the machining precision of final paper handkerchief wrapping bag.

Further, in the step 2, the air inlet quantity is controlled by the flow controller to be 5000 plus 6000 square meters per hour, and the air temperature at the air outlet end of the cold air pipe is 8-15 ℃.

The flow controller can be balanced control the circulation of wind in the single cold wind pipe for each cold wind pipe spun cold wind volume is balanced, makes the side of crude product membrane by further even cooling, and the corresponding shaping degree of consistency that can promote the individual membrane more is convenient for follow-up the polychrome printing processing that carries out the pattern.

The refrigerator is further included, one end of the air inlet of the cold air pipe is communicated with the refrigerator, and the refrigerator controls the temperature of the air in the cold air pipe to be 8-15 ℃.

When the ambient temperature outside the film blowing machine was too high, if the air in the environment was absorbed naturally to the cold wind pipe, can lead to the high temperature of cold wind pipe spun cold wind, can't play the effect of carrying out rapid cooling to the crude film, when absorbing the air in the environment naturally simultaneously, also can lead to cold wind pipe spun cold wind temperature inconsistent, lead to the cooling condition of crude film unstable, can direct influence the tension and the smoothness of crude film.

Further, the film blowing machine comprises an outer layer spiral body for forming a first layer of film in an extrusion mode, a middle layer spiral body for forming a second layer of film in an extrusion mode and an inner layer spiral body for forming a third layer of film in an extrusion mode, the outer layer spiral body, the middle layer spiral body and the inner layer spiral body are coaxially installed in the film blowing machine, and an annular cavity for enabling the first layer of film, the second layer of film and the third layer of film to be extruded and combined into a crude product film is formed in the film blowing.

The extrusion of the first layer film, the second layer film and the third layer film is realized through the arrangement of the outer layer spiral body, the middle layer spiral body and the inner layer spiral body; meanwhile, after the first layer of film, the second layer of film and the third layer of film are mixed into the annular cavity, the top end of the annular cavity can extrude and form the crude film.

The film blowing machine is characterized by further comprising a cooling unit for cooling the inner wall of the crude product film, wherein the cooling unit comprises an air inlet pipe, a cooling pipe and an air outlet pipe, the cooling pipe is vertically and fixedly arranged in the film blowing machine, and a plurality of air outlets opposite to the inner wall of the crude product film are formed in the side wall of the cooling pipe; one end of the cooling pipe, which is far away from the crude membrane, is communicated with the air inlet pipe and the air outlet pipe.

When the crude film is cooled, the outside of the cold air pipe is removed, cold air can enter the air inlet pipe, and after the cold air enters the cooling pipe, the cold air impacts the inner wall of the crude film through the air outlet of the cooling pipe to cool the inner wall of the crude film, and after the cold air exchanges heat with hot air, the hot air is discharged from the air outlet pipe; meanwhile, the crude product film can be cooled by cold air blown out of the cooling pipe and the cold air pipe together, so that the crude product film can be rapidly cooled, and the processing speed of the crude product film is increased.

Further, the temperature of the raw materials in the outer layer spiral body, the middle layer spiral body and the inner layer spiral body is 130-160 ℃.

After the temperature is adopted, the raw materials for forming the first layer film, the second layer film and the third layer film can be fully melted and mixed, the raw materials have sufficient fluidity, the first layer film, the second layer film and the third layer film which are conveniently formed are kept in a uniform state, the finally formed crude product film also has good uniformity, and the product quality of the crude product film is improved.

Further, the crude membrane tension was controlled at 8-15N.

The tension of the crude film is further limited, the stiffness of the crude film can be further accurately controlled, the single-layer film is more stably conveyed in the subsequent printing process, and the stability and the integrity of pattern printing are further enhanced.

Further, the thickness of the crude film was 3.0 to 8.5. mu.m.

After the thickness of the crude film is controlled to be 3.0-8.5 mu m, the stiffness of the crude film is more suitable for a paper towel packaging bag, and the completeness of pattern printing can be improved.

Further, the overprinting precision is less than or equal to 0.3 mm.

Through the control of the thickness and the tension of the crude product film, the area of the printing defect can be further reduced, so that the final overprinting precision is less than or equal to 0.3mm, and the completeness of pattern printing on the paper towel packaging bag is improved.

Drawings

FIG. 1 is a process flow diagram of a process for producing a degradable environment-friendly plastic product in example 1 of the present invention;

FIG. 2 is a structural sectional view in the main view direction of the film blowing machine in step 2 of example 1 of the present invention;

FIG. 3 is a structural sectional view in the main view direction of a film blowing machine in embodiment 2 of the present invention;

FIG. 4 is a longitudinal sectional view of the air ring and the air intake unit in embodiment 2 of the present invention;

fig. 5 is a sectional view of the air ring and the air intake unit a-a of fig. 4.

Detailed Description

The following is further detailed by the specific embodiments:

reference numerals in the drawings of the specification include: the device comprises an outer die body 10, an air ring 11, an outer transition body 12, an inner transition body 13, a mouth die 14, an adjusting ring 15, an outer layer spiral body 16, a middle layer spiral body 17, an inner layer spiral body 18, a first extrusion cavity 106, a second extrusion cavity 107, a third extrusion cavity 108, an annular cavity 19, an air inlet pipe 20, a cooling pipe 21, a heat exchanger body 22, an air outlet pipe 23, a cold air pipe 24, a support 25, a fixed shaft 26, a roller 27, an upper ring 28, an air outlet plate 29, a lower ring 30, an upper sealing plate 31, a lower sealing plate 32, a V-shaped plate 33, a plane bearing 34 and a temperature insulation layer 35.

Example 1

Example 1 is substantially as shown in figures 1 and 2: a production process of a degradable environment-friendly plastic product comprises the following steps:

step 1, preparing the following raw materials, by mass, 11-18 parts of P L A, 70 parts of PBAT, 2 parts of a slipping agent and 1 part of an opening agent.

Step 2: preparing a film blowing machine, a refrigerator and a printing machine, wherein the film blowing machine comprises an annular air ring 11, an outer transition body 12, an inner transition body 13, a mouth mold 14, an adjusting ring 15, an outer mold body 10, an outer layer spiral body 16 for forming a first layer of film by extrusion, a middle layer spiral body 17 for forming a second layer of film by extrusion and an inner layer spiral body 18 for forming a third layer of film by extrusion, the outer layer spiral body 16, the middle layer spiral body 17 and the inner layer spiral body 18 are coaxially welded in the outer mold body 10 from outside to inside, the lower surface of the outer transition body 12 is welded with the upper end face of the outer mold body 10, and the lower surface of the outer transition body 12 is opposite to the upper end face of the outer; the lower surface of the inner transition body 13 is welded with the upper end surface of the inner layer spiral body 18, and the lower surface of the inner transition body 13 is opposite to the upper end surface of the middle layer spiral body 17.

A first extrusion cavity 106 for extruding a first film is formed between the outer wall of the outer layer spiral body 16, the inner wall of the outer die body 10 and the lower surface of the outer transition body 12, a second extrusion cavity for extruding a second film is formed between the outer wall of the middle layer spiral body 17 and the outer wall of the outer layer spiral body 16, and a third extrusion cavity 108 for extruding a third film is formed between the outer wall of the inner layer spiral body 18, the outer wall of the middle layer spiral body 17 and the lower surface of the inner transition body 13. The lower surface of the neck ring mold 14 is welded with the upper surface of the inner transition body 13, the adjusting ring 15 is welded with the upper surface of the outer transition body 12, and meanwhile, an annular cavity 19 is formed among the outer wall of the neck ring mold 14, the inner wall of the adjusting ring 15, the outer wall of the inner transition body 13 and the outer wall of the inner transition body 13; while the top ends of the first extrusion chamber 106, the second extrusion chamber 107 and the third extrusion chamber 108 are all in communication with the annular chamber 19.

The film blowing machine is also provided with a cooling unit, the cooling unit comprises an air inlet pipe 20, a heat exchanger, an air outlet pipe 23, four cold air pipes 24 and flow controllers for controlling the four cold air pipes 24 to uniformly supply air, the heat exchanger is fixedly arranged on the upper surface of the neck mold 14 through bolts and comprises a cooling pipe 21 and a heat exchanger body 22, the cooling pipe 21 is vertically and coaxially welded in the outer mold body 10, the upper end of the cooling pipe 21 penetrates through the heat exchanger body 22 and the neck mold 14 and is opposite to the inner wall of the crude film, a plurality of air outlets are formed in the side wall of the cooling pipe 21, the lower end of the cooling pipe 21 is communicated with the air inlet pipe 20 and the air outlet pipe 23, the lower end of the outer mold body 10 is fixedly provided with an air chamber through bolts, the air chamber is communicated with a refrigerating machine through pipelines, the air chamber is communicated with the lower ends of the four cold air pipes 24, the flow controllers in the four cold air pipes 24 are P L C controllers, the lower surface of the air ring 11 is welded on the upper surface of the adjusting ring 15, the upper ends of the four.

And step 3: preparing three storage barrels and three extruders in one-to-one correspondence with the three storage barrels, wherein raw materials simultaneously enter a first storage barrel, a second storage barrel and a third storage barrel, then the first extruder absorbs the raw materials in the first storage barrel and is communicated with a first extrusion cavity 106, the second extruder absorbs the raw materials in the second storage barrel and is communicated with a second extrusion cavity 107, and the third extruder absorbs the raw materials in the third storage barrel and is communicated with a third extrusion cavity 108; the raw materials are subjected to hot melting and conveying by the three extruders, so that the temperature of the raw materials entering the first extrusion cavity 106, the second extrusion cavity 107 and the third extrusion cavity 108 is 130-160 ℃, the raw materials in the first extrusion cavity 106, the second extrusion cavity 107 and the third extrusion cavity 108 are extruded to the annular cavity 19 under the action of the extrusion pressure of the three extruders, and a cylindrical crude product film is formed at the top end of the annular cavity 19; the refrigerator controls the temperature of the cold air at 8-15 ℃, the cold air is transmitted to four cold air pipes 24 through pipelines and an air chamber in sequence, the flow controller controls the air inlet quantity in a single cold air pipe 24 to be 5000 plus 6000 square meters per hour, and the cold air acts on the outer wall of the crude product film through an air ring 11 to rapidly cool the crude product film; meanwhile, the air inlet pipe 20 supplies air into the cooling pipe 21, the cold air sprayed out of the cooling pipe 21 cools the inner wall of the crude film, and the heat exchange machine body 22 also carries out heat exchange treatment on the cooling pipe 21, so that hot air is sprayed out of the air outlet pipe 23; through the cooling and film blowing processes, the tension of the crude film is controlled to be 8-15N, and the thickness of the crude film is 3.0-8.5 mu m.

And 4, step 4: pressing and conveying the crude film in the step 2 to enable the crude film to form a double-layer film sheet; then cutting the edge of the double-layer film sheet to form a single-layer film;

and 5: and (3) respectively rolling the two layers of single-layer films in the step (4), then arranging the rolled single-layer films on a feeding roller of a printer, and printing patterns on the surfaces of the single-layer films by the printer, wherein the tension of the single-layer films is controlled to be 8-15N, the thickness of the single-layer films is 3.0-8.5 microns, the single-layer films can be stably and flatly tensioned on the printer for printing, so that the overprinting precision is less than or equal to 0.3mm, and identification information such as patterns and bar codes on paper towel packages can be printed clearly.

The printing quality of the paper towel packaging bag printed in the embodiment 1 is obviously improved compared with that of supermarket shopping bags and continuous-rolling freshness protection bags in the prior art; meanwhile, compared with the conventional PE paper towel packaging bag, the paper towel packaging bag processed in the embodiment 1 has a natural degradable function, is more environment-friendly and better meets the development trend of the technology.

The printing effect detection and degradation duration detection are carried out on the paper towel packaging bags, supermarket shopping bags and continuous rolling freshness protection bags printed in the embodiment 1, and two supermarket shopping bag films printed with different supermarket logos are selected as a printing sample 1 and a printing sample 2; selecting two continuous rolls of preservative bag films of different brands as a printing sample 3 and a printing sample 4, wherein QS descriptions of single colors are printed on the printing sample 3 and the printing sample 4; selecting the single-layer film finished in the processing in the example 1 to form a printing sample 5 and a printing sample 6, and printing patterns of different brands on the printing sample 5 and the printing sample 6; meanwhile, the areas of the printing sample 1, the printing sample 2, the printing sample 3, the printing sample 4, the printing sample 5 and the printing sample 6 are the same, after the printing sample 1, the printing sample 2, the printing sample 3, the printing sample 4, the printing sample 5 and the printing sample 6 are printed, the printing precision, the printing defect condition and the degradation condition of each sample are detected, and then the following detection data are obtained:

TABLE 1

As can be seen from table 1, the overprint precision of the printed samples 5 and 6 is obviously better than that of the printed samples 1-4, and meanwhile, the printed samples 5 and 6 also have the effects of multicolor printing and good color development; meanwhile, when the thickness of the printing sample 5 and the printing sample 6 reaches 3-4 times of the thickness of the printing sample 1-4, the time for composting and degrading is only doubled, and the degradability of the printing sample 5 and the printing sample 6 is obviously better than that of the printing sample 1-4.

Example 2

Embodiment 2 is different from embodiment 1 in that embodiment 2 is basically as shown in fig. 3, fig. 4 and fig. 5, the left and right ends of the plenum are provided with support units, the support units comprise a bracket 25, a fixed shaft 26 and a roller 27, the two ends of the fixed shaft 26 penetrate through the roller 27 and are welded with the bracket 25, the axle center of the roller 27 is in sliding contact with the fixed shaft 26, and one end of the bracket 25, which is far away from the roller 27, is welded with the vertical side surface of the plenum; when needs move whole inflation film manufacturing machine according to the processing needs, can promote whole inflation film manufacturing machine and remove, gyro wheel 27 and ground rolling contact this moment realize the change to the inflation film manufacturing machine position, also be convenient for carry whole inflation film manufacturing machine.

The air ring 11 comprises an upper ring 28, an air outlet plate 29 and a lower ring 30 which are sequentially arranged from top to bottom, the upper ring 28, the air outlet plate 29 and the lower ring 30 are both annular, the air outlet plate 29 is vertically inclined and is provided with a plurality of vent holes on the air outlet plate 29, the upper end of the air outlet plate 29 is welded with the inner ring wall of the upper ring 28, the lower end of the air outlet plate 29 is welded with the inner ring wall of the lower ring 30, the air outlet plate 29 is a cambered surface which is sunken in the direction of the outer ring of the upper ring 28 and the lower ring 30, the cambered surface of the air outlet plate 29 is opposite to a crude product film extruded from the top end of the annular cavity 19, a plane bearing 34 is arranged between the lower surface of the lower ring 30 and the upper end surface of the adjusting ring 15, the lower surface of the plane bearing 34 penetrates through the mouth mold.

The quantity of cold air pipe 24 is 8, be equipped with a plurality of air inlet units between upper ring 28 and the lower ring 30, the air inlet unit includes annular upper seal plate 31, lower seal plate 32 and vertical eight V type boards 33 that set up between upper ring 28 and lower ring 30, single V type board 33 sets up between two adjacent cold air pipes 24, and the one end of V type board 33 and the end welding of a cold air pipe 24, and the other end of V type board 33 and the end welding of adjacent cold air pipe 24, the tip that cold air pipe 24 was kept away from to V type board 33 is circular-arc, V type board 33 is fixed with thermal-insulated layer 35 that bonds on one side of air-out board 29 far away from, upper seal plate 31 covers the up end of eight V type boards 33 and with upper ring 28 lower surface sliding seal connection, lower seal plate 32 covers the lower terminal surface of eight V type boards 33 and with lower ring 30 upper surface sliding seal connection.

Compared with the embodiment 1, the production process of the degradable environment-friendly plastic product in the embodiment has the following difference in use, when a crude product film is extruded from the top of the annular cavity 19 to be cooled, cold air is sprayed out of the upper ends of 8 cold air pipes 24 and enters the space among the upper sealing plate 31, the lower sealing plate 32 and the V-shaped plates 33, at the moment, the spraying range of the cold air in each cold air pipe 24 can be divided by one side of each two adjacent V-shaped plates 33, and the sprayed cold air can be guided, so that the cold air in the 8 cold air pipes 24 is quickly and uniformly sprayed to the air outlet plate 29, and the outer wall of the crude product film outside the air outlet plate 29 is uniformly cooled; in this process, the setting of V type board 33, upper seal plate 31 and lower seal plate 32 can reduce the air inlet scope of wind ring 11 originally, and heat insulating layer 35 can insulate against the cold wind between V type board 33, upper seal plate 31 and the lower seal plate 32 simultaneously, can make the cold wind that enters into in the wind ring 11 can by abundant utilization.

Meanwhile, when the crude product film is cooled, the upper ends of the cold air pipes 24 are fixed, so that the 8 cold air pipes 24, the upper sealing plate 31, the lower sealing plate 32 and the V-shaped plate 33 are fixed relative to the air ring 11, at the moment, the lower ring 30 is rotated, the lower ring 30 drives the upper end face of the plane bearing 34 to rotate relative to the adjusting ring 15, at the moment, the lower ring 30 drives the upper ring 28 and the air outlet plate 29 to synchronously rotate, at the moment, the relative positions of the air outlet plate 29 and the upper ends of the cold air pipes 24 are changed, cold air can be further uniformly sprayed out of each part of the air outlet plate 29, and the outer wall of the crude product film is cooled more uniformly; in the process, the plane bearing 34 can keep the rotating upper ring 28, the air outlet plate 29 and the lower ring 30 in a coaxial state with the crude membrane and in a stable rotating state.

Claims

1. A production process of a degradable environment-friendly plastic product is characterized by comprising the following steps:

2. The production process of the degradable environment-friendly plastic product according to claim 1, wherein in the step 1, the film blowing machine is provided with a plurality of cold air pipes and a flow controller for controlling uniform air inlet of the cold air pipes, in the step 2, one end of the cold air pipe for air outlet is opposite to the side wall of the crude product film, and one end of the cold air pipe for air outlet is uniformly opposite to the peripheral surface of the crude product film.

3. The production process of the degradable environment-friendly plastic product according to claim 2, wherein in the step 2, the air inlet amount is controlled by the flow controller to be 5000-6000 square meters per hour, and the air temperature at the air outlet end of the cold air pipe is 8-15 ℃.

4. The production process of the degradable environment-friendly plastic product according to claim 3, characterized by further comprising a refrigerator, wherein one end of the air inlet of the cold air pipe is communicated with the refrigerator, and the refrigerator controls the temperature of the air in the cold air pipe to be 8-15 ℃.

5. The production process of degradable environment-friendly plastic products according to any one of claims 1 to 4, wherein the film blowing machine comprises an outer layer spiral body for forming a first layer of film by extrusion, a middle layer spiral body for forming a second layer of film by extrusion and an inner layer spiral body for forming a third layer of film by extrusion, the outer layer spiral body, the middle layer spiral body and the inner layer spiral body are coaxially arranged in the film blowing machine, and an annular cavity for extruding and merging the first layer of film, the second layer of film and the third layer of film into a crude film is arranged in the film blowing machine.

6. The production process of the degradable environment-friendly plastic product according to claim 5, further comprising a cooling unit for cooling the inner wall of the crude film, wherein the cooling unit comprises an air inlet pipe, a cooling pipe and an air outlet pipe, the cooling pipe is vertically and fixedly installed in the film blowing machine, and a plurality of air outlets opposite to the inner wall of the crude film are arranged on the side wall of the cooling pipe; and one end of the cooling pipe, which is far away from the crude product film, is communicated with the air inlet pipe and the air outlet pipe.

7. The process for producing degradable environment-friendly plastic product according to claim 1 or 6, wherein the temperature of the raw materials in the outer layer helix, the middle layer helix and the inner layer helix is 130-160 ℃.

8. The process for producing a degradable environment-friendly plastic product according to claim 7, wherein the crude film tension is controlled to be 8-15N.

9. The process for producing a degradable environment-friendly plastic product according to claim 8, wherein the thickness of the crude film is 3.0-8.5 μm.

10. The process for producing a degradable environment-friendly plastic product according to claim 9, wherein the overprinting precision is less than or equal to 0.3 mm.