A process for producing high strength plastic film

Abstract

The application belongs to the technical field of packaging materials, and particularly relates to a high-strength plastic film production process which comprises film coating, pressing, folding, rolling and trimming. In the application, the fiber film is pasted with the covering film, so that the produced plastic film contains fibers. Then, the fibers are pressed after folding, so that the fibers are staggered, the uniformity of the connection between the fibers and the film material is improved, the reinforcing effect of the fibers is improved, the fibers form a three-dimensional structure in the plastic film after folding, the connectivity between the fibers is improved, the integrity of the plastic film is improved, the structural strength of the plastic film is further improved, and the quality of the plastic film is improved. Meanwhile, the flatness of the rolled plastic film is better, and the plastic film is more beautiful.

Description

Technical Field

[0001] This invention belongs to the field of packaging materials technology, specifically a high-strength plastic film production process. Background Technology

[0002] Films made of polyvinyl chloride, polyethylene, polypropylene, polystyrene, and other resins are used for packaging and as coating layers. Plastic packaging and plastic packaging products are gaining an increasingly larger market share, especially composite plastic flexible packaging, which is widely used in the food, pharmaceutical, and chemical industries. Food packaging accounts for the largest proportion, including beverage packaging, frozen food packaging, retortable food packaging, and fast food packaging. These products have brought great convenience to people's lives.

[0003] With the development of materials, plastic packaging films are usually used to package and protect the goods during express delivery. However, during the transit of goods, traditional plastic packaging films, which mainly serve a protective function, generally have low strength, which can lead to damage to the plastic packaging film and consequently damage to the contents. Therefore, a plastic packaging film with higher strength is needed for transportation. Summary of the Invention

[0004] To overcome the shortcomings of existing technologies, this invention proposes a high-strength plastic film production process. This invention primarily addresses the problem of low strength and susceptibility to breakage in existing plastic films.

[0005] The technical solution adopted by this invention to solve its technical problem is: a high-strength plastic film production process, comprising the following steps:

[0006] S1: The raw materials are melted and blown into a covering film, and fibers are added to the blown covering film to make a fiber film.

[0007] S2: Overlap the cover film obtained in step S1 above with the fiber film, and then press them together to form an initial film material. The cover film is disposed on the side close to the fiber of the fiber film.

[0008] S3: The initial film material is then folded along one side of its length to form uniform V-shaped folds;

[0009] S4: After all the initial film material has been folded, the initial film material is rolled in one direction using a roller pressing device;

[0010] S5: Subsequently, the initial film material after rolling is subjected to flat extrusion, maintaining a temperature of 60-75℃ and a pressure of not less than 10N for more than 15 minutes.

[0011] S6: The initial film material is then trimmed and wound to complete the production of the plastic packaging film.

[0012] During operation, bonding the fiber membrane to the cover membrane results in a plastic film containing fibers. Due to the high strength of these fibers, the overall strength of the plastic film is increased. Subsequent folding and pressing further increases the interlacing of the fibers, improving the uniformity of the connection between the internal fibers and the film material, thus enhancing the reinforcing effect. Folding creates a three-dimensional spatial structure within the plastic film, further improving the connectivity between fibers and enhancing the overall integrity and structural strength of the film. Rolling is then performed... This process allows for a smoother surface on the folded film, improving its aesthetics and overall quality. Furthermore, the unidirectional rolling process (rolling in the direction of the folds and separating from the initial film material upon return) prevents the folds from shifting or folding during rolling, thus avoiding the formation of large bumps. This results in better film uniformity, improved strength uniformity, and enhanced film quality. Additionally, the smoothness of the rolled film further enhances its aesthetics.

[0013] Preferably, the ratio of the lengths of the two sides forming the fold is 1:2.

[0014] During operation, by setting the ratio of the two sides of the folds to 2, the short sides of adjacent folds are positioned above and below each other on the long side during the compression process. This results in a film with twice the original thickness and uniform thickness, making the folded and rolled film more uniform in thickness and surface, thus improving strength. Simultaneously, because the film contains fibers and the limiting membrane is uniform, the folds formed during rolling are also uniform, resulting in more uniform fiber distribution within the produced plastic film. Since the fibers provide high strength to the film, a uniformly distributed fiber distribution leads to more uniform strength in the produced plastic film, improving film quality. Furthermore, because the folded film has uniform folds without protrusions or depressions, subsequent rolling processes do not require pushing the film to achieve a relatively smooth surface, resulting in high film production efficiency, reduced manufacturing difficulty, and ultimately, lower production costs for the plastic film.

[0015] Preferably, the folding method of the initial film material includes the following steps:

[0016] Q1: Lay the initial membrane material flat on a plane, and then place the folding mold on top of the initial membrane material;

[0017] Q2: After completing the above steps, apply negative pressure starting from one end of the folding mold to make the initial film material adhere to the folding mold.

[0018] Q3: After applying negative pressure and the folding mold is in place, maintain the pressure and then push the initial film material to the other end in sequence until all the initial film material is completely in place with the folding mold;

[0019] Q4: Then heat the mold at 50°C for 10 minutes while maintaining the adsorption pressure on the initial film material. Then remove the adsorption pressure, take out the initial film material, and complete the folding of the initial film material.

[0020] During operation, the folding mold effectively adsorbs the initial film material, ensuring it maintains the same shape as the contact surface. This gradual adsorption allows the film to adhere more smoothly to the mold surface, resulting in folds that more closely match the mold's shape and are more uniform. This improves the folding quality and uniformity, leading to a more consistent strength in the produced plastic film. Heating softens the initial film material. Due to its thermoplasticity, the softened and cooled material retains the same shape as when in contact with the mold, maintaining stable folds and preventing changes in folds during subsequent processes. This improves the quality of the produced film. Furthermore, this folding method allows for rapid folding, eliminating the time required for mechanical flipping and improving efficiency. It also reduces folding errors, enhances consistency and uniformity, and ultimately improves the quality of the plastic film.

[0021] Preferably, the folding mold includes a body; the lower part of the body is provided with a pleated section; the pleated section has a continuous sawtooth structure; the interior of the pleated section is divided into multiple independent cavities; the troughs of the pleated section are respectively connected to the independent cavities; a pressure sensor is provided inside each independent cavity for detecting the internal air pressure; each independent cavity is respectively connected to an external vacuum device; a heating component is provided at the upper part of the folding mold for heating the folding mold.

[0022] During operation, a folding mold is placed on the initial film material. An external vacuum system creates negative pressure in an independent cavity at one end, adsorbing the film at the bottom of the corresponding fold. Because one end of the film is pressed down, it moves from the other end of the folding mold and adheres to the fold. An internal pressure detector maintains pressure until it stabilizes and reaches a fixed value, indicating that the fold is completely sealed and the initial film material has adhered to the fold. The signal is then transmitted to the controller, which then controls the next independent cavity... The vacuum equipment operates to adsorb the film at the fold, thus adhering the film to the fold. This process is repeated once, followed by heating the fold by a controller to heat the film and set the initial film material. Heating is then stopped and the vacuum is removed, completing the folding process. This device enables stable and rapid film folding, improving folding efficiency. The operation is simple and easy for personnel, and folding through the folded area ensures uniformity, thus improving folding quality.

[0023] Preferably, the folding mold further includes a rubber pad and a damping wheel; the rubber pad is provided at one end of the body near the folded portion; the rubber pad is fixedly connected to the body; and the damping wheel is connected to the other end of the body.

[0024] During operation, a rubber pad is placed on one side of the main body. Due to the high frictional resistance between the rubber pad and the film, the film can be pressed more stably, preventing slippage and making the folding process more stable, thus improving the folding quality. Simultaneously, a damping wheel is placed on the other side of the main body, ensuring the film remains taut at all times during the adsorption and folding process. This prevents excessive film movement under adsorption pressure, avoiding irregular wrinkles inside the main body, thus ensuring the uniformity of the initial film material after folding. This, in turn, ensures the uniformity of fiber distribution throughout the produced plastic film, improving the uniformity of film strength. Furthermore, the damping wheel isolates dust and debris from the film before it enters the folded sections, preventing external debris from being folded into the folds, further improving the uniformity of the produced film, enhancing the consistency of film strength, and ultimately improving film quality.

[0025] Preferably, the suction pressure of the suction port on the pleated part decreases sequentially according to the order of suction; the pressure reduction value is 0.15-0.3MPa.

[0026] During operation, the film undergoes sequential adsorption folding. When a subsequent fold is formed, the previously folded folds are still in an adsorbed state. Therefore, to ensure that the folds are uniform after folding, the later folds must not affect the already folded folds. Thus, in this solution, the pressure at the fold exhaust port is gradually reduced to prevent the subsequent exhaust process from causing the already folded folds to move, thereby ensuring the uniformity of the folds, improving the uniformity of fiber distribution in the plastic film, improving the uniformity of the plastic film strength, and ultimately improving the quality of the plastic film.

[0027] Preferably, the roller is a driven roller when rolling in one direction.

[0028] During operation, the rolling action is passive, ensuring that the rolling rollers exert pressure solely on the film during the rolling process. This prevents the initial wrinkles on the film from shifting, thus guaranteeing the uniformity of wrinkles and the distribution of fibers within the plastic film, thereby improving the uniformity of the film's strength. Furthermore, because the rolling rollers do not actively rub against the film surface during rolling, scratches are avoided, resulting in a smoother finished film surface and ultimately enhancing the film's quality.

[0029] Preferably, the crests and troughs of the pleated body are all rounded.

[0030] During operation, rounded corners at the troughs make the curve of the folded portion relatively smooth. Since the film mainly relies on negative pressure adsorption during folding, if the turning point of the fold is a zigzag shape, it will be difficult for the film to fully adhere to the fold, resulting in weak adsorption and unstable adsorption force, which may lead to the risk of film movement. Therefore, by setting rounded corners at the troughs, the film can be more stably adsorbed at the fold, thereby improving the folding efficiency. Since the film will shrink and move inward towards the trough during folding, rounded corners at the crests make the crests relatively smooth, allowing the film to slide more easily into the trough, ensuring the film is fully unfolded, avoiding uneven folding caused by obstruction, further improving the folding quality, and preventing damage to the film during the folding process.

[0031] Preferably, the fiber membrane includes a base membrane and a fiber layer; the fiber layer is disposed on one side of the base membrane and is embedded in the base membrane;

[0032] The initial film material is rolled in one direction, which includes the following steps:

[0033] M1: Use a smooth roller to roll the folded initial film material until it is flat;

[0034] M2: The initial film material is then heated to soften it, and then the initial film material is rolled in a staggered manner 2-3 times using a roller with holes;

[0035] M3: Then, the film material is rolled again with a smooth roller until it is flat, completing the rolling process.

[0036] During operation, since the fiber membrane is composed of a single layer of fiber and base film, one side of the fiber is embedded inside the base film, and the other side of the fiber contacts the cover film when forming the initial film material. In this solution, the initial film material is first rolled by a smooth roller to maintain a flatter shape after folding. Then, it is squeezed by a roller with holes, which causes some of the film material on the base film to pass through the holes in the fiber layer and enter the cover film. Then, it is rolled again by a smooth roller, which creates a partial connection between the base film and the cover film, thereby increasing the connection strength between the base film and the cover film, improving the integrity of the initial film material, avoiding the delamination of the film material during folding, improving the overall performance of the produced plastic film, and thus improving the quality of the plastic film.

[0037] Preferably, the method for preparing the fiber membrane includes the following steps:

[0038] K1: Spread the base film flat, and then evenly spread the plant fibers on the base film;

[0039] K2: Then heat the base film until it softens, and at the same time apply vibration to the base film at a frequency of 60-80 Hz and an amplitude of 1-2 mm until half of the fiber is embedded in the base film, then stop vibrating.

[0040] K3: Then the base membrane is cooled to 5°C for 5 minutes, then the base membrane is rolled flat, and then the fiber membrane is restored to room temperature to complete the preparation of the fiber membrane.

[0041] During operation, plant fibers are first spread onto the base film and then heated, which facilitates the even distribution of the plant fibers. The base film is then softened, and vibration allows the plant fibers to quickly penetrate the film without the aid of tools, thus improving the production efficiency of the fiber membrane. This also avoids contamination from tools entering the base film, which could cause uneven distribution and affect fiber strength. After the base film has cooled to a near-complete state, it is then rolled to prevent over-rolling and to level the fiber membrane, thereby improving its quality.

[0042] The beneficial effects of this invention are as follows:

[0043] 1. In this invention, by bonding the fiber membrane and the covering membrane, the produced plastic film contains fibers. Since fibers have high strength, this increases the strength of the plastic film. Subsequently, by folding and pressing, the interlacing between fibers is increased, thereby improving the uniformity of the connection between the internal fibers and the film material, and thus enhancing the reinforcing effect of the fibers. Folding also creates a three-dimensional spatial structure within the plastic film, improving the connectivity between fibers, enhancing the overall integrity of the plastic film, and further improving its structural strength. This is further enhanced by rolling. This process results in a smoother surface for the folded film, improving its aesthetics and overall quality. Furthermore, the unidirectional rolling process (rolling in the direction of the folds and separating from the initial film material during rolling back) prevents the folds from shifting or folding, thus avoiding the formation of large bumps. This leads to better film uniformity, improved strength uniformity, and ultimately, better film quality. The resulting smoother surface further enhances the film's appearance.

[0044] 2. In this invention, by setting the ratio of the two sides of the folds to 2, during the compression process, the short sides of adjacent folds are positioned above and below each other on the long side, resulting in a film with twice the original thickness and uniform thickness. This makes the thickness of the folded and rolled film more uniform, the surface smoother, and the strength more uniform. Simultaneously, because the film contains fibers and the limiting membrane is uniform, the folds formed after rolling are also uniform, resulting in more uniform fibers within the produced plastic film. Since the fibers provide high strength to the film, a uniformly distributed film results in more uniform strength, thus improving film quality. Furthermore, because the folded film has uniform folds without protrusions or depressions, subsequent rolling processes do not require pushing the film to achieve a relatively smooth surface, leading to high film production efficiency, reduced manufacturing difficulty, and ultimately, improved plastic film manufacturing costs.

[0045] 3. In this invention, the folding mold provides excellent adsorption, allowing the initial film material to be adsorbed onto the mold. This ensures the initial film material maintains the same shape as the contact surface with the mold. As the film is gradually adsorbed, it adheres more smoothly to the mold surface, resulting in folds that more closely match the mold shape and are more uniform. This improves the folding quality and uniformity, leading to a more uniform strength in the produced plastic film. Heating softens the initial film material. Due to its thermoplasticity, the initial film material retains the same shape as when in contact with the mold after softening and cooling, ensuring stable folds and preventing changes in folds during subsequent processes. This improves the quality of the produced film. Furthermore, this folding method allows for rapid folding, avoiding the time required for mechanical flipping and improving efficiency. It also reduces folding errors, improves consistency and uniformity, and ultimately enhances the quality of the plastic film.

[0046] 4. In this invention, a rubber pad is provided on one side of the main body. Due to the high frictional resistance between the rubber pad and the film, the film can be pressed more stably, preventing slippage and making the folding process more stable, thus improving the folding quality. Simultaneously, a damping wheel is provided on the other side of the main body, ensuring the film remains taut at all times during the adsorption and folding process. This prevents excessive film movement due to adsorption pressure, avoiding irregular wrinkles inside the main body, thus ensuring the uniformity of the initial film material after folding. This, in turn, ensures the uniformity of fiber distribution throughout the produced plastic film, improving the uniformity of film strength. Furthermore, the damping wheel isolates dust and debris from the film before it enters the folded area, preventing external debris from being folded into the folds, further improving the uniformity of the produced film, enhancing the consistency of film strength, and ultimately improving film quality.

[0047] 5. In this invention, since the film undergoes sequential adsorption folding during the folding process, the previously folded folds are all in an adsorbed state when a subsequent fold is made. Therefore, to ensure that the folded folds are uniform, the later folds should not affect the already folded folds. Thus, in this solution, by gradually reducing the pressure at the fold exhaust port, the movement of the already folded folds can be avoided during the subsequent exhaust process, thereby ensuring the uniformity of the folds, improving the uniformity of fiber distribution in the plastic film, improving the uniformity of the plastic film strength, and ultimately improving the quality of the plastic film. Attached Figure Description

[0048] The invention will now be further described with reference to the accompanying drawings.

[0049] Figure 1 This is a flowchart of the production process of the plastic film in this invention;

[0050] Figure 2 This is a schematic diagram of the overall structure of the folding mold in this invention;

[0051] Figure 3 This is a schematic diagram of the structure of the plastic film after folding in this invention;

[0052] Figure 4 This is a schematic diagram of the structure of the folded part in this invention;

[0053] Figure 5 This is a schematic diagram of the plastic film after it has been rolled by the driving roller in this invention;

[0054] Figure 6 This is a schematic diagram of the structure of the plastic film after it has been rolled in this invention.

[0055] In the figure: 1. Body; 2. Wrinkled part; 3. Independent cavity; 4. Valley; 5. Peak; 6. Pressure sensor; 7. Heating component; 8. Rubber pad; 9. Damping wheel; 10. Base film; 11. Covering film; 12. Fiber layer. Detailed Implementation

[0056] To make the technical means, creative features, objectives and effects of this invention easier to understand, the invention will be further described below in conjunction with specific embodiments.

[0057] like Figure 1 The aforementioned high-strength plastic film production process includes the following steps:

[0058] S1: The raw materials are melted and blown into a covering film, and fibers are added to the blown covering film to make a fiber film.

[0059] S2: Overlap the cover film obtained in step S1 above with the fiber film, and then press them together to form an initial film material. The cover film is disposed on the side close to the fiber of the fiber film.

[0060] S3: The initial film material is then folded along one side of its length to form uniform V-shaped folds;

[0061] S4: After all the initial film material has been folded, the initial film material is rolled in one direction using a roller pressing device;

[0062] S5: Subsequently, the initial film material after rolling is subjected to flat extrusion, maintaining a temperature of 60-75℃ and a pressure of not less than 10N for more than 15 minutes.

[0063] S6: The initial film material is then trimmed and wound to complete the production of the plastic packaging film.

[0064] During operation, bonding the fiber membrane to the cover membrane results in a plastic film containing fibers. Due to the high strength of these fibers, the overall strength of the plastic film is increased. Subsequent folding and pressing further increases the interlacing of the fibers, improving the uniformity of the connection between the internal fibers and the film material, thus enhancing the reinforcing effect. Folding creates a three-dimensional spatial structure within the plastic film, further improving the connectivity between fibers and enhancing the overall integrity and structural strength of the film. Rolling is then performed... This process allows for a smoother surface on the folded film, improving its aesthetics and overall quality. Furthermore, the unidirectional rolling process (rolling in the direction of the folds and separating from the initial film material upon return) prevents the folds from shifting or folding during rolling, thus avoiding the formation of large bumps. This results in better film uniformity, improved strength uniformity, and enhanced film quality. Additionally, the smoothness of the rolled film further enhances its aesthetics.

[0065] The ratio of the lengths of the two sides forming the fold is 1:2.

[0066] During operation, by setting the ratio of the two sides of the folds to 2, the short sides of adjacent folds are positioned above and below each other on the long side during the compression process. This results in a film with twice the original thickness and uniform thickness, making the folded and rolled film more uniform in thickness and surface, thus improving strength. Simultaneously, because the film contains fibers and the limiting membrane is uniform, the folds formed during rolling are also uniform, resulting in more uniform fiber distribution within the produced plastic film. Since the fibers provide high strength to the film, a uniformly distributed fiber distribution leads to more uniform strength in the produced plastic film, improving film quality. Furthermore, because the folded film has uniform folds without protrusions or depressions, subsequent rolling processes do not require pushing the film to achieve a relatively smooth surface, resulting in high film production efficiency, reduced manufacturing difficulty, and ultimately, lower production costs for the plastic film.

[0067] The folding method of the initial film material includes the following steps:

[0068] Q1: Lay the initial membrane material flat on a plane, and then place the folding mold on top of the initial membrane material;

[0069] Q2: After completing the above steps, apply negative pressure starting from one end of the folding mold to make the initial film material adhere to the folding mold.

[0070] Q3: After applying negative pressure and the folding mold is in place, maintain the pressure and then push the initial film material to the other end in sequence until all the initial film material is completely in place with the folding mold;

[0071] Q4: Then heat the mold at 50°C for 10 minutes while maintaining the adsorption pressure on the initial film material. Then remove the adsorption pressure, take out the initial film material, and complete the folding of the initial film material.

[0072] During operation, the folding mold effectively adsorbs the initial film material, ensuring it maintains the same shape as the contact surface. This gradual adsorption allows the film to adhere more smoothly to the mold surface, resulting in folds that more closely match the mold's shape and are more uniform. This improves the folding quality and uniformity, leading to a more consistent strength in the produced plastic film. Heating softens the initial film material. Due to its thermoplasticity, the softened and cooled material retains the same shape as when in contact with the mold, maintaining stable folds and preventing changes in folds during subsequent processes. This improves the quality of the produced film. Furthermore, this folding method allows for rapid folding, eliminating the time required for mechanical flipping and improving efficiency. It also reduces folding errors, enhances consistency and uniformity, and ultimately improves the quality of the plastic film.

[0073] like Figure 2 and Figure 3 As shown, the folding mold includes a body 1; a pleated section 2 is provided at the lower part of the body 1; the pleated section 2 has a continuous sawtooth structure; the interior of the pleated section 2 is divided into multiple independent cavities 3; the troughs 4 of the pleated section 2 are respectively connected to the independent cavities 3; a pressure sensor 6 is provided inside the independent cavity 3 for detecting the air pressure inside the cavity; the independent cavities 3 are respectively connected to external vacuum equipment; a heating component 7 is provided at the upper part of the folding mold for heating the folding mold.

[0074] During operation, the folding mold is placed on the initial film material. Then, an external vacuum device creates negative pressure in one of the independent cavities, adsorbing the film at the bottom of the corresponding fold 2. Because one end of the film is pressed down, it moves from the other end of the folding mold and is then adsorbed and adhered to the fold 2. An internal pressure detector maintains pressure until it stabilizes and reaches a fixed value, indicating that the fold is completely sealed and the initial film material at that fold has adhered to the fold 2. The signal is then transmitted to the controller, which then controls the next independent cavity... The vacuum equipment operates to adsorb the film at the fold, thus adhering the film to the fold 2. This process is repeated once. Then, the controller controls the heating element 7 to heat the fold 2, thereby heating the film and shaping the initial film material. Heating is then stopped and the vacuum is removed, completing the folding process. Because this device can achieve stable and rapid film folding, it can improve folding efficiency. At the same time, the operation is simple during the folding process, which is convenient for personnel. Furthermore, folding through the fold 2 can achieve uniformity of folds, thereby improving the folding quality.

[0075] like Figure 2 As shown, the folding mold also includes a rubber pad 8 and a damping wheel 9; the rubber pad 8 is provided at one end of the body 1 near the folded part 2; the rubber pad 8 is fixedly connected to the body 1; and the damping wheel 9 is connected to the other end of the body 1.

[0076] During operation, a rubber pad 8 is placed on one side of the main body 1. Due to the high frictional resistance between the rubber pad 8 and the film, the film can be pressed more stably, preventing slippage and making the folding process more stable, thus improving the folding quality. At the same time, a damping wheel 9 is placed on the other side of the main body 1, which keeps the film taut at all times during the film adsorption and folding process. This prevents the film from moving excessively under the pressure of adsorption, thus avoiding irregular wrinkles inside the main body 1. This ensures the uniformity of the initial film material after folding, and the uniformity of fiber distribution in the produced plastic film, thereby improving the uniformity of film strength. In addition, the damping wheel 9 can isolate dust and debris on the film before it enters the folded part 2, preventing external debris from being folded into the folds. This improves the uniformity of the produced film, the consistency of film strength, and the overall quality of the film.

[0077] The air extraction pressure at the extraction port on the pleated part 2 decreases sequentially according to the order of extraction; the pressure reduction value is 0.15-0.3MPa.

[0078] During operation, the film undergoes sequential adsorption folding. When a subsequent fold is formed, the previously folded folds are still in an adsorbed state. Therefore, to ensure that the folds are uniform after folding, the later folds must not affect the already folded folds. Thus, in this solution, the pressure at the fold exhaust port is gradually reduced to prevent the subsequent exhaust process from causing the already folded folds to move, thereby ensuring the uniformity of the folds, improving the uniformity of fiber distribution in the plastic film, improving the uniformity of the plastic film strength, and ultimately improving the quality of the plastic film.

[0079] When compacting in one direction, the compaction roller is the driven compaction roller.

[0080] During operation, the rolling action is passive, ensuring that the rolling rollers exert pressure solely on the film during the rolling process. This prevents the initial wrinkles on the film from shifting, thus guaranteeing the uniformity of wrinkles and the distribution of fibers within the plastic film, thereby improving the uniformity of the film's strength. Furthermore, because the rolling rollers do not actively rub against the film surface during rolling, scratches are avoided, resulting in a smoother finished film surface and ultimately enhancing the film's quality.

[0081] like Figure 4 As shown, the peaks 5 and troughs 4 of the body 1 of the pleated part 2 are all rounded.

[0082] During operation, rounded corners at trough 4 make the curve of the folded portion relatively smooth. Since the film mainly relies on negative pressure adsorption during folding, if the turning point of the fold is a zigzag shape, it will be difficult for the film to fully adhere to the fold, resulting in weak adsorption and unstable adsorption force, which may lead to the risk of film movement. Therefore, by setting rounded corners at trough 4, the film can be more stably adsorbed at the fold, thereby improving the folding efficiency. Since the film will shrink and move inward towards the trough 4 during folding, rounded corners at peak 5 make the peak 5 relatively smooth, allowing the film to slide more easily into the trough 4, ensuring the film is fully unfolded, avoiding uneven folding caused by obstruction, further improving the folding quality, and preventing damage to the film during folding.

[0083] like Figure 5 and Figure 6 As shown, the fiber membrane includes a base membrane and a fiber layer; the fiber layer is disposed on one side of the base membrane and is embedded in the base membrane;

[0084] The initial film material is rolled in one direction, which includes the following steps:

[0085] M1: Use a smooth roller to roll the folded initial film material until it is flat;

[0086] M2: The initial film material is then heated to soften it, and then the initial film material is rolled in a staggered manner 2-3 times using a roller with holes;

[0087] M3: Then, the film material is rolled again with a smooth roller until it is flat, completing the rolling process.

[0088] During operation, since the fiber membrane is composed of a single layer of fiber and base film, one side of the fiber is embedded inside the base film, and the other side of the fiber contacts the cover film when forming the initial film material. In this solution, the initial film material is first rolled by a smooth roller to maintain a flatter shape after folding. Then, it is squeezed by a roller with holes, which causes some of the film material on the base film to pass through the holes in the fiber layer and enter the cover film. Then, it is rolled again by a smooth roller, which creates a partial connection between the base film and the cover film, thereby increasing the connection strength between the base film and the cover film, improving the integrity of the initial film material, avoiding the delamination of the film material during folding, improving the overall performance of the produced plastic film, and thus improving the quality of the plastic film.

[0089] The method for preparing the fiber membrane includes the following steps:

[0090] K1: Spread the base film flat, and then evenly spread the plant fibers on the base film;

[0091] K2: Then heat the base film until it softens, and at the same time apply vibration to the base film at a frequency of 60-80 Hz and an amplitude of 1-2 mm until half of the fiber is embedded in the base film, then stop vibrating.

[0092] K3: Then the base membrane is cooled to 5°C for 5 minutes, then the base membrane is rolled flat, and then the fiber membrane is restored to room temperature to complete the preparation of the fiber membrane.

[0093] During operation, plant fibers are first spread onto the base film and then heated, which facilitates the even distribution of the plant fibers. The base film is then softened, and vibration allows the plant fibers to quickly penetrate the film without the aid of tools, thus improving the production efficiency of the fiber membrane. This also avoids contamination from tools entering the base film, which could cause uneven distribution and affect fiber strength. After the base film has cooled to a near-complete state, it is then rolled to prevent over-rolling and to level the fiber membrane, thereby improving its quality.

[0094] During operation, bonding the fiber membrane to the cover membrane results in a plastic film containing fibers. Due to the high strength of these fibers, the overall strength of the plastic film is increased. Subsequent folding and pressing further increases the interlacing of the fibers, improving the uniformity of the connection between the internal fibers and the film material, thus enhancing the reinforcing effect. Folding creates a three-dimensional spatial structure within the plastic film, further improving the connectivity between fibers and enhancing the overall integrity and structural strength of the film. Rolling further smooths the surface of the folded film. Improving the aesthetics of the film surface, thereby enhancing film quality, and because unidirectional rolling is used during construction (the rolling direction is along the direction of the folds, separating from the initial film material upon rolling back), it avoids pushing and folding the folds during rolling, thus preventing the formation of large bumps. This results in better film uniformity, improving the uniformity of the plastic film's strength and ultimately enhancing its quality. It also improves the flatness of the rolled plastic film, further enhancing its aesthetics. By setting the ratio of the folds on both sides to 2, the folds are compressed during the rolling process, causing adjacent folds to... The short sides of the film are positioned on the top and bottom of a long side, forming a film twice the original thickness with uniform thickness. This results in a more uniform thickness and smoother surface after folding and rolling, leading to more uniform strength. Simultaneously, the presence of fibers within the film and the uniformity of the limiting membrane ensure that the folds formed during rolling are evenly distributed, resulting in more uniform fiber distribution within the produced plastic film. Since fibers provide high strength to the film, even distribution leads to more uniform strength and improved film quality. Furthermore, the uniform folds without protrusions or depressions in the folded film facilitate subsequent processes. The rolling and flattening process achieves a relatively flat surface without pushing the film, resulting in high film production efficiency and reduced production difficulty, thus increasing the manufacturing cost of plastic film. The folding mold provides excellent adsorption, allowing the initial film material to be adsorbed onto the mold and maintain the same shape as the contact surface. As the film is gradually adsorbed, it adheres more smoothly to the mold surface, resulting in folds that more closely match the mold shape and are more uniform. This improves the folding quality and uniformity, leading to more uniform strength in the produced plastic film.Subsequently, heating softens the initial film material. Because the initial film material is thermoplastic, after softening and cooling, it maintains the same shape as when in contact with the mold. This ensures the wrinkles remain stable and do not change in subsequent processes, thus improving the quality of the produced film. Furthermore, this folding method allows for rapid folding, avoiding the time required for mechanical flipping and folding, thereby increasing folding efficiency. This method also reduces folding errors, improves consistency and uniformity, and ultimately enhances the quality of the plastic film.

[0095] The embodiments of the present invention have been described above with reference to the accompanying drawings. However, the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention without departing from the spirit and scope of the claims. All of these forms are within the protection scope of the present invention.

Claims

1. A process for the production of high strength plastic film, characterized by: It comprises the following steps: S1: melt the raw materials and blow them into a cover film, and add fibers to the blown cover film to form a fiber film; S2: overlap the cover film and the fiber film prepared in step S1, and then press them into an initial film, with the cover film arranged close to the fiber side of the fiber film; S3: then fold one side of the initial film along the length direction to form uniform V-shaped folds; S4: after all the initial films are folded, roll the initial films in one direction by a rolling device; S5: then plate extrude the rolled initial films, keep the temperature at 60-75℃, the pressure not less than 10N, and keep for more than 15 minutes; S6: then trim and wind the initial films to complete the production of the plastic packaging film.

2. The process for producing a high-strength plastic film according to claim 1, characterized by: The ratio of the length of the two sides of the fold forming the fold is 1:

2.

3. The process for producing a high-strength plastic film according to claim 2, characterized by: The folding method of the initial film comprises the following steps: Q1: lay the initial film on a plane, and then place a folding die on the upper part of the initial film; Q2: after the above steps, start applying negative pressure from one end of the folding die to make the initial film adhere to the folding die; Q3: keep the pressure until the negative pressure is applied after the folding die adheres, and then advance to the other end of the initial film in sequence until all the initial films completely adhere to the folding die; Q4: then heat the die to 50℃ for 10 minutes, keep the adsorption pressure on the initial film, then remove the adsorption pressure, take out the initial film, and complete the folding of the initial film.

4. The process for producing a high-strength plastic film according to claim 3, characterized by: The folding die comprises a body (1); the lower part of the body (1) is provided with a fold part (2); the fold part (2) is a continuous sawtooth structure; the inner part of the fold part (2) is divided into a plurality of independent cavities (3); the positions of the valleys (4) of the fold part (2) are respectively communicated with the independent cavities (3); the independent cavities (3) are provided with pressure sensors (6) inside for detecting the air pressure inside the cavities; the independent cavities (3) are respectively communicated with external vacuum devices.

5. The process for producing a high-strength plastic film according to claim 4, characterized by: The folding die further comprises a rubber pad (8) and a damping wheel (9); one end of the body (1) close to the fold part (2) is provided with the rubber pad (8); the rubber pad (8) is fixedly connected with the body (1); the other end of the body (1) is connected with the damping wheel (9).

6. A method of construction suitable for use in the high-strength plastic film production process of claim 5, characterized by: The air extraction pressure of the air extraction port on the fold part (2) decreases in sequence according to the order of air extraction; the pressure reduction value is 0.15-0.3MPa.

7. The construction method of the high-strength plastic film production process according to claim 6, wherein the rolling roller is a driven rolling roller during one-direction rolling.

8. The construction method of the high-strength plastic film production process according to claim 7, wherein the peaks (5) and valleys (4) of the body (1) of the fold part (2) are all provided with round corners.

9. The process for producing a high-strength plastic film according to claim 5, characterized by: The fiber film comprises a base film and a fiber layer; the fiber layer is arranged on one side of the base film and embedded with the base film; The one-direction rolling of the initial film comprises the following steps: M1: use a smooth roller to roll the folded initial film to be flat; M2: then heat the initial film material to soften it, then misalign the initial film material with the roller with holes and roll it 2-3 times; M3: then roll the film material with the smooth roller to flatten it, complete the rolling work.

10. The process for producing a high-strength plastic film according to claim 5, characterized by: The preparation method of the fiber film comprises the following steps: K1: spread the base film flat, then evenly spread the fibers on the base film; K2: then heat the base film until it softens, at the same time, apply vibration to the base film, the vibration frequency is 60-80 Hz, the amplitude is 1-2 mm, until half of the fibers are embedded in the base film, stop the vibration; K3: then cool the base film by 5℃ for 5 minutes, then roll the base film flat, then until the fiber film returns to room temperature, complete the preparation of the fiber film.

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