JP7460069B2 - Method and device for recovering thermoplastic resin film from polyvinylidene chloride coating film - Google Patents

Description

The present invention relates to a method for removing a polyvinylidene chloride coating layer from a thermoplastic resin film coated with polyvinylidene chloride, and recycling and recovering the thermoplastic resin film, and an apparatus therefor.
More specifically, a method for recycling and recovering thermoplastic resin films by continuously processing polyvinylidene chloride-coated films without cutting or pulverizing them to remove the polyvinylidene chloride coating layer. and a device therefor.

Films in which polyvinylidene chloride is coated on thermoplastic resin films such as polyamide, polypropylene, or polyester are known as K-coated films and are used as various food packaging films due to their excellent oxygen barrier and water vapor barrier properties. These films are usually manufactured in a rolled form, but during the manufacturing process, trimming losses due to cutting off both ends, products that fail inspection, and products that have been stored in stock for a long period of time (long-term products) may occur. Such trimming losses, products that fail inspection, and long-term products cannot be disposed of by incineration because they are coated with chlorine-based polyvinylidene chloride, and are often landfilled. However, from the perspective of reducing waste and making effective use of resources, there is an increasing demand for separating, recovering, and reusing thermoplastic resin films and polyvinylidene chloride, and a simple and efficient recovery method is desired.

Methods are known for separating and recovering each resin component from a laminate film having a polyvinylidene chloride layer or a film coated with polyvinylidene chloride.
For example, Patent Document 1 discloses a method in which a polyvinylidene chloride resin laminate molding is coarsely pulverized, then finely pulverized, and then treated in an aqueous solution containing a surfactant to precipitate and separate the polyvinylidene chloride resin.
Patent Document 2 discloses a method of stirring an olefin resin substrate having a vinylidene chloride resin coating layer in an aqueous solution having a surfactant concentration of 0.1 wt % or more at a temperature lower than the temperature at which the resin substrate melts by 100° C. or more. Example 1 discloses that a 30 μm-thick biaxially oriented polypropylene film coated with 5 μm-thick polyvinylidene chloride is cut into pieces of approximately 5 mm square, stirred in an aqueous solution containing a surfactant, and the polyvinylidene chloride is allowed to settle and separated, and the polypropylene floating on the top is collected.

Patent Document 3 discloses a method in which a resin base coated with or containing additives such as adhesives, coating agents, softeners, pressure sensitive adhesives, anti-fogging agents, stabilizers, and bactericides is stirred in a petroleum-based solvent at a temperature of 100°C or less to dissolve and remove the additives, and the resin base and additives are separated and recovered. In the examples, it is disclosed that a 30 μm-thick biaxially oriented polypropylene film coated with a 5 μm-thick coating agent resin is cut into approximately 5 mm squares, stirred in kerosene, filtered, and the polypropylene is recovered, and the coating agent resin is recovered from the filtrate using a concentrator, and the kerosene solvent is reused.

However, in the methods of Patent Documents 1 to 3, the coating film that has been crushed or cut is stirred in an aqueous surfactant solution or a solvent, and it is necessary to remove the settled or floating film or resin by filtration. , operation becomes complicated. Furthermore, since it is processed in a batch manner, it cannot be said to be an efficient method for processing a large amount of coating film.

On the other hand, as a method for continuously separating and recovering laminated sheets and films in sheet or film form without crushing or cutting them, the example of Patent Document 4 includes polypropylene (PP), ethylene-vinyl acetate copolymer By heating a 5-layer multilayer sheet (PP/EVA/PVDC/EVA/PP) co-extruded with an adhesive resin such as (EVA) and polyvinylidene chloride (PVDC) with a heating roll, and then passing it through a rotating roll. A method of separating into three layers: , PP, EVA/PVDC/EVA, and PP is disclosed. However, this method utilizes the fact that heating the multilayer sheet reduces the adhesive strength between the adhesive resin and the resin to be adhered to a level that allows for peeling. It cannot be applied to coating films that are applied directly to thermoplastic resin films.

Japanese Patent Application Laid-Open No. 5-261735 Japanese Patent Application Publication No. 9-279066 JP 2001-123004 A Japanese Unexamined Patent Publication No. 2-131907

The present invention has been made in consideration of the above circumstances, and aims to provide a method for simply and efficiently separating polyvinylidene chloride from a thermoplastic resin film coated with polyvinylidene chloride and regenerating and recovering the thermoplastic resin film, as well as an apparatus suitable for this purpose.

In order to solve the above problems, the present inventors discovered that a thermoplastic resin film coated with polyvinylidene chloride can be easily and efficiently recovered by continuously passing the film through a dissolution tank containing an organic solvent without crushing or cutting it, while still in a long state wound up on a roll or the like, to dissolve and remove the polyvinylidene chloride, regenerating the thermoplastic resin film, drying it, and then continuously winding it up, thereby arriving at the present invention.

That is, the present invention processes a polyvinylidene chloride coating film in the order of steps 1 to 4 , and in step 1, the polyvinylidene chloride coating film is processed in a plurality of dissolving tanks having different tank lengths, and is wound up. The coating layer of polyvinylidene chloride is placed on the bottom side of the melting tank, which is passed through a plurality of melting tanks in which the tank length is shortened toward the roller side, and a scraper is installed at the bottom of the melting tank. Provided is a recovery method characterized in that a polyvinylidene chloride coating layer is removed from a polyvinylidene chloride coated film by passing it through an organic solvent while contacting with a scraper , and the thermoplastic resin film is recovered.
Step 1: Dissolving the polyvinylidene chloride coating layer in an organic solvent from a thermoplastic resin film coated with polyvinylidene chloride Step 2: Scraping off the organic solvent from the thermoplastic resin film that has passed through the organic solvent Step 3 :Step of drying the thermoplastic resin film Step 4: Step of winding up and collecting the thermoplastic resin film

The present invention also provides a recovery device for removing a polyvinylidene chloride coating layer from a polyvinylidene chloride coating film and recovering a thermoplastic resin film, comprising:
(A) unwinding roller;
(B) a dissolution tank capable of storing an organic solvent and equipped with a scraper at the bottom capable of contacting the lower surface of the polyvinylidene chloride coating film;
(C) means for scraping off the organic solvent adhering to the film pulled out of the organic solvent;
(D) Drying tank;
(E) Take-up roller;
has
The recovery device is characterized in that the dissolving tank is composed of a plurality of dissolving tanks having different tank lengths, and the length of the dissolving tank becomes shorter toward the winding roller side. provide.

According to the method and apparatus for recovering thermoplastic resin film from polyvinylidene chloride coated film of the present invention, there is no need to crush or cut the thermoplastic resin film coated with polyvinylidene chloride, and the polyvinylidene chloride can be removed. Since there is no need to separate the thermoplastic resin film after filtration or the like, polyvinylidene chloride can be separated from the thermoplastic resin film with a simple operation, and the thermoplastic resin film can be recycled and recovered. Furthermore, since the process can be performed continuously, the thermoplastic resin film can be efficiently recovered from a large amount of polyvinylidene chloride coated film.

FIG. 1 is a diagram showing an embodiment of a collection device of the present invention.

Each step of the recovery method for recovering a thermoplastic resin film from a polyvinylidene chloride coated film (hereinafter referred to as PVDC coated film) of the present invention will be described in detail below. The recovery method of the present invention is a method of continuously processing PVDC coated film, and since it is possible to process a large amount of PVDC coated film easily and efficiently, It is most effective when applied to PVDC coated film.

(Step 1)
Step 1 is a step of dissolving the polyvinylidene chloride coating layer from the PVDC-coated film in an organic solvent. For example, a roll of the PVDC-coated film set on a winding roller is unwound, introduced into a dissolution tank storing an organic solvent and having a scraper installed at the bottom, and passed through the organic solvent stored in the dissolution tank. The PVDC-coated film is preferably sent into the dissolution tank with the polyvinylidene chloride coating layer on the lower layer side, and passed through the organic solvent while the polyvinylidene chloride coating layer is in contact with the scraper. In this way, polyvinylidene chloride that has absorbed the organic solvent and swelled to become a gel is scraped off, so that polyvinylidene chloride can be efficiently separated.

The organic solvent used is not particularly limited as long as it dissolves polyvinylidene chloride but does not dissolve the thermoplastic resin film. Suitable organic solvents vary depending on the type of thermoplastic resin film, but for example, when the thermoplastic resin film is a polyamide resin film, ethers such as diethyl ether and tetrahydrofuran, ketones such as acetone and methyl ethyl ketone, benzene and toluene are used. Aromatic hydrocarbons such as the following can be used. Among them, it is preferable to use tetrahydrofuran because it has excellent solubility in polyvinylidene chloride.

Examples of the thermoplastic resin constituting the thermoplastic resin film include resins for base films of PVDC coated films, such as polypropylene resins, polyester resins, and polyamide resins, among which polyamide resins are preferred. Examples of the polyamide resin include polycaproamide (nylon 6) resin, polyhexamethylene adipamide (nylon 66) resin, polytetramethylene adipamide (nylon 46) resin, and polyhexamethylene sebacamide (nylon 610). Resin, polyhexamethylene dodecamide (nylon 612) resin, polyundecaneamide (nylon 11) resin, polydodecanamide (nylon 12) resin, polyhexamethylene terephthalamide (nylon 6T) resin, polyhexamethylene isophthalamide ( Nylon 6I) resin, and mixtures thereof, or copolymerized nylon resins containing two or more of these nylon components (polycaproamide/polyhexamethyleneadipamide copolymer (nylon 6/66), polycaproamide/ Polyhexamethylene terephthalamide copolymer (nylon 6/6T), polyhexamethylene adipamide/polyhexamethylene terephthalamide copolymer (nylon 66/6T), polyhexamethylene adipamide/polyhexamethylene isophthalamide copolymer (nylon 66/6T) 6I), polyhexamethylene adipamide/polyhexamethylene isophthalamide/polycaproamide copolymer (nylon 66/6I/6)), and the like.

Among these, nylon resins with a melting point of 200°C or higher are preferred in terms of heat resistance, and examples of such resins include nylon 6, nylon 66, nylon 610, nylon 6/66 copolymer, nylon 66/6I copolymer, and nylon 66/6I/6 copolymer. Furthermore, nylon 6 and nylon 66 are preferred in terms of mechanical properties.

The organic solvent in which the PVDC-coated film is immersed may or may not be heated. The higher the temperature during immersion, the easier it is to dissolve polyvinylidene chloride, but as the temperature increases, the organic solvent becomes more likely to volatilize, worsening the working environment. Therefore, when heating, it is desirable to select the temperature appropriately, taking into consideration the boiling point and volatility of the organic solvent used. For example, when using tetrahydrofuran as the organic solvent, a temperature between room temperature and about 40°C is preferable, taking into consideration the deterioration of the working environment due to volatilization.

When a PVDC coated film is continuously immersed in an organic solvent to dissolve and remove polyvinylidene chloride, the concentration of polyvinylidene chloride in the organic solvent increases as the immersion process progresses. The amount of polyvinylidene chloride contained in the organic solvent used also increases. As a result, if only one dissolution tank is used and the immersion treatment is performed only once, polyvinylidene chloride will remain on the thermoplastic resin film recovered as the treatment progresses, and the thermoplastic resin film will be reused. This may be a problem if you do so.

In order to prevent polyvinylidene chloride from remaining on the recovered thermoplastic resin film, it is desirable to immerse the PVDC coated film in an organic solvent multiple times. Therefore, it is preferable to install a plurality of dissolution tanks storing organic solvents, to sequentially pass the PVDC coated film through the plurality of dissolution tanks, and to immerse it in the organic solvent stored in each dissolution tank. The amount of polyvinylidene chloride in the PVDC coated film decreases as it passes through the dissolution tank, and the concentration of polyvinylidene chloride contained in the organic solvent in the dissolution tank gradually decreases, so the stage at which the immersion process is completed It is possible to reduce as much as possible the amount of polyvinylidene chloride derived from organic solvents that adheres to thermoplastic resin films.

The number of times the PVDC-coated film is immersed in the organic solvent (i.e., the number of dissolution tanks) can be appropriately selected depending on the thickness of the polyvinylidene chloride coating layer, the processing speed, etc. A preferred number of times is 2 to 5 times (units), and a more preferred number of times (number of dissolution tanks) is 3 to 4 times (units). If the number of times of immersion is increased, the consumption of organic solvent increases, reducing the economic efficiency, and if the number of times of immersion is decreased, the polyvinylidene chloride remains, causing the film to turn yellow after drying.

The amount of polyvinylidene chloride remaining in the PVDC-coated film decreases as it passes through each dissolution tank, so the immersion time in each dissolution tank can be shortened successively. By shortening the immersion time in each dissolution tank, it becomes possible to successively reduce the size (length) of the connected dissolution tanks. By shortening the length of the dissolution tanks, it is possible to simplify the equipment and reduce the amount of organic solvent used.

It is preferable to install a scraper at the bottom of each of the multiple dissolution tanks and bring the scraper into contact with the polyvinylidene chloride coating layer side of the PVDC-coated film to scrape off as much polyvinylidene chloride as possible that has dissolved in the organic solvent or absorbed the organic solvent and swelled.

(Step 2)
Step 2 is a step of scraping off the adhering organic solvent from the thermoplastic resin film that has been passed through an organic solvent and the polyvinylidene chloride coating layer has been removed, and one or both sides of the thermoplastic resin film is brought into contact with a scraper. This is done by letting It is preferable to use a plurality of scrapers, and they are installed in series or in opposing positions. Note that in the present invention, the scraper can be made of rubber, resin, metal, or the like.

By dissolving polyvinylidene chloride in an organic solvent multiple times, the amount of polyvinylidene contained in the organic solvent that adheres to the thermoplastic resin film that is finally drawn out from the organic solvent decreases, but the amount of adhered organic By scraping off the solvent, it is possible to further reduce the remaining polyvinylidene chloride. Furthermore, by completely eliminating redeposition of the organic solvent using the scraper in the final dissolution tank, the load when drying the thermoplastic resin film in the next step 3 can be reduced and the drying efficiency can be increased.

This step 2 may be carried out between steps 1 and 1. That is, when passing through multiple dissolution tanks in step 1, a step of scraping off the organic solvent from the thermoplastic resin film that has passed through the organic solvent is carried out. In this way, polyvinylidene chloride that has adhered to the thermoplastic resin film and has been swollen by the organic solvent is scraped off, and the polyvinylidene chloride can be efficiently dissolved in the next step 1.

(Step 3)
Step 3 is a step of drying the thermoplastic resin film from which the polyvinylidene chloride has been removed, and the thermoplastic resin film is introduced into a drying tank and dried.

Drying methods that can be used include hot air drying, vacuum drying, drum drying, and drying with infrared or far infrared rays, and multiple drying methods can be combined. From the standpoint of simplicity and speed, hot air drying is preferred. The drying temperature is 20 to 150°C, preferably 50 to 80°C.

(Step 4)
Step 4 is a step of removing the polyvinylidene chloride coating layer from the PVDC coated film and recovering the recycled thermoplastic resin film. The thermoplastic resin film is collected by continuously winding it up using a winding roller equipped with a paper tube or the like.

It is advisable to control the rotation speed of the winding roller so that the PVDC coated film passes through the dissolving tank and drying tank at a constant speed and is then wound up.

The winding speed of the long PVDC-coated film is selected appropriately depending on the thickness of the polyvinylidene chloride coating layer, the type of organic solvent used, the immersion temperature in the organic solvent, etc., but it is preferably about 1 to 8 m/min.

The collected thermoplastic resin film can be reused as a base resin for a PVDC coated film, a molded product, and the like.
The degree of polymerization of the recovered thermoplastic resin film is not particularly limited as long as it can be subjected to normal molding processing, but in the case of polyamide resin, it was measured at 25°C in a 1% by weight 98% concentrated sulfuric acid solution. It is preferable that the relative viscosity is in the range of 2 to 4.

Next, the details of the recovery device for removing the polyvinylidene chloride coating layer from the PVDC coated film of the present invention and recovering the thermoplastic resin film will be described in detail.

The recovery device of the present invention is composed of a series of devices connected together: (A) unwinding roller (1), (B) dissolution tanks (2a-2c), (C) scrapers (30f, 30g) as scraping means, (D) drying tank (4), and (E) winding roller (5). As described above, it is preferable to use multiple dissolution tanks in order to prevent polyvinylidene chloride from remaining on the recovered thermoplastic resin film as much as possible. The scraping means (scraper) is installed in the final dissolution tank (3).

The recovery apparatus of the present invention is shown in FIG. 1 as an embodiment in which there are three dissolution tanks.
The unwinding roller (1) is a roller that sets the PVDC coated film wound up into a roll, and operates in conjunction with the winding roller (5) to send out the PVDC coated film to the dissolving tank (2a). Guide rollers (10a to 10c) are installed between the unwinding roller (1) and the dissolving tank (2a) to feed the PVDC coated film into the dissolving tank (2a).

The three dissolution tanks (2a-2c) and the final dissolution tank (3) are all tanks for storing organic solvents, but as the amount of polyvinylidene chloride on the PVDC-coated film decreases toward the winding roller, the amount of organic solvent required decreases accordingly, and so the length of each dissolution tank and the final dissolution tank shortens in stages. That is, the second dissolution tank (2b) is shorter than the first dissolution tank (2a), the third dissolution tank (2c) is shorter than the second dissolution tank (2b), and the final dissolution tank (3) is shorter than the third dissolution tank (2c), making it the shortest dissolution tank.

Guide rollers (10c to 10j) are installed at the inlets and outlets of the three dissolving tanks (2a to 2c) and the final dissolving tank, and each dissolving tank and the final dissolving tank are coated with a PVDC coated film. Two guide rollers (20a to 20h) (hereinafter referred to as presser rollers) are each installed to press the material so that it does not float in the organic solvent. As a result, the PVDC coated film is immersed in the organic solvent and sent to the next tank.

In addition, scrapers (30a to 30e) are installed between two pressure rollers at the bottom of the three dissolution tanks, and the tips of the scrapers are in contact with the lower surface of the PVDC-coated film. The number of scrapers to be installed in each dissolution tank is not particularly specified, but since the amount of polyvinylidene chloride on the PVDC-coated film in the first dissolution tank (2a) is large and the amount of polyvinylidene chloride dissolved in the organic solvent is also large, it is preferable to install multiple scrapers (two scrapers, 30a and 30b in Figure 1). Figure 1 shows an example in which two scrapers (30c and 30d) are also installed in the second dissolution tank (2b), but since the amount of polyvinylidene chloride on the PVDC-coated film in the second dissolution tank is less than that in the first dissolution tank (2a), only one scraper may be installed. In the third dissolution tank (2c), the amount of polyvinylidene chloride on the PVDC-coated film is even less, and the length of the dissolution tank itself is short, so only one scraper (30e) is installed.

A scraper may be provided at the bottom of the final dissolution tank (3), but at the final dissolution tank stage, the amount of polyvinylidene chloride on the PVDC coated film is extremely small, and the length of the dissolution tank is also the shortest. Therefore, the bottom scraper is basically unnecessary. Rather, in the final melting tank (3), two scrapers (30f, 30g) are installed closer to the take-up roller than the guide roller (10j) at the outlet so as to be in contact with both sides of the thermoplastic resin film. It is important to. Since the organic solvent adhering to the thermoplastic resin film can be scraped off by the scraper, polyvinylidene chloride dissolved in the organic solvent can be prevented from remaining on the thermoplastic resin film.

Although not shown, each of the three dissolution tanks (2a to 2c) and the final dissolution tank (3) has an injection port on the top surface for injecting the organic solvent, and an injection port on the bottom for extracting the organic solvent. A drain port is provided.

The thermoplastic resin film leaving the final dissolution tank (3) is introduced into a drying tank (4). The inside of the drying tank (4) is set at 50 to 60°C. The thermoplastic resin film drawn out via the guide roller (10k) at the inlet is dried in the drying tank, then passed through the guide roller (10l) at the outlet, and then wound into the drying tank (4). It passes through a guide roller (10 m) installed between rollers (5) and is wound up onto a winding roller (5).

The winding roller (5) winds up and collects the thermoplastic resin film regenerated by removing the polyvinylidene chloride coating layer from the PVDC-coated film. A paper tube for winding up the film into a roll is attached to the winding roller (5), and the rotation speed can be controlled in conjunction with the unwinding roller (1) to keep the winding speed constant.

The present invention will be explained in more detail below with reference to examples, but the present invention is not limited to the following examples.

Example 1
A polyamide 6 film recovery test was carried out using a 225 mm wide roll (hereinafter referred to as a PVDC-coated PA roll) on which a polyamide 6 film having a length of approximately 500 m and a coating layer of polyvinylidene chloride having a thickness of approximately 20 μm was wound up, using the device shown in FIG. 1.

The PVDC-coated PA roll was set on the unwinding roller (1) of the device shown in FIG. 1 with the polyvinylidene chloride coating layer facing downward.
A nylon film consisting only of polyamide 6 and having the same width as the PVDC-coated PA roll, which had a length reaching from the unwinding roller (1) to the take-up roller (5) of the apparatus in Figure 1, was attached to the tip of the PVDC-coated PA roll, and the film was passed through three dissolution tanks (2a to 2c), a final dissolution tank (3) and a drying tank (4) and wound around the take-up roller (5). Next, tetrahydrofuran was filled into the three dissolution tanks and the final dissolution tank to a depth that did not contact the guide rollers installed at the inlet and outlet of each dissolution tank and the final dissolution tank and that allowed the PVDC-coated PA roll to be fully immersed.

The winding roller (5) of the apparatus shown in FIG. 1 is driven while controlling the winding speed to be 3 m/min, and the PVDC coated PA roll is pulled out from the unwinding roller (1), and the three melting tanks are It passed through a final dissolution tank and a drying tank and was wound up on a winding roller (5). Note that hot air at 50° C. was circulated in the drying tank (4).

After the PVDC-coated PA roll was wound onto the winding roller (5), the film was cut out from three locations, corresponding to the first 1/3 of the treatment, the middle 1/3, and the last 1/3, and infrared absorption spectra were measured and a heating test (200°C for 2 hours) was performed.

In the measurement of infrared absorption spectra, no spectrum derived from polyvinylidene chloride was observed in any of the films, and only a spectrum derived from polyamide 6 resin was observed.

In the heating test, the polyamide 6 film coated with polyvinylidene chloride turned brown, whereas all the cut-out films were transparent and no coloring was observed.

The results of infrared absorption spectrum measurements and heating tests show that the polyvinylidene chloride coating layer was removed from the PVDC coated film and the polyamide 6 film was regenerated.

According to the present invention, it is possible to continuously remove polyvinylidene chloride from a thermoplastic resin film coated with polyvinylidene chloride to regenerate the thermoplastic resin. Thermoplastic resin films can be efficiently collected from long trimming losses, inspection-failed products, and long-standing products, and can be reused.

1: Unwinding roller 2a to 2c: Dissolving tank 3: Final dissolving tank 4: Drying tank 5: Winding roller 10a to 10m: Guide roller 20a to 20h: Guide roller (press roller)
30a-30g: scraper

Claims (6)

A recovery method comprising the steps of: treating a polyvinylidene chloride-coated film in the order of steps 1 to 4; in step 1, passing the polyvinylidene chloride-coated film sequentially through a plurality of dissolution tanks having different tank lengths, the plurality of dissolution tanks being configured so that the tank lengths become shorter toward a take-up roller; passing the polyvinylidene chloride-coated film through a dissolution tank having a scraper installed at the bottom, with the polyvinylidene chloride coating layer at the bottom, while being in contact with the scraper in an organic solvent , thereby removing the polyvinylidene chloride coating layer from the polyvinylidene chloride-coated film and recovering a thermoplastic resin film.
Step 1: A step of dissolving the polyvinylidene chloride coating layer from the polyvinylidene chloride-coated thermoplastic resin film in an organic solvent. Step 2: A step of scraping off the organic solvent from the thermoplastic resin film that has passed through the organic solvent. Step 3: A step of drying the thermoplastic resin film. Step 4: A step of winding and recovering the thermoplastic resin film. 2. The method for recovering polyvinylidene chloride according to claim 1, further comprising the steps of: performing step 2 when passing the thermoplastic resin film through a plurality of dissolution tanks in step 1; and scraping off polyvinylidene chloride swollen with the organic solvent that adheres to the thermoplastic resin film that has passed through the organic solvent in step 2 . 3. The method according to claim 1 , wherein the thermoplastic resin is a polyamide resin. The recovery method according to any one of claims 1 to 3 , wherein the organic solvent is tetrahydrofuran. A recovery apparatus for removing a polyvinylidene chloride coating layer from a polyvinylidene chloride coating film and recovering a thermoplastic resin film, comprising:
(A) unwinding roller;
(B) a dissolution tank capable of storing an organic solvent and having a scraper disposed at the bottom thereof capable of contacting the lower surface of the polyvinylidene chloride coating film;
(C) a means for scraping off the organic solvent adhering to the film pulled out of the organic solvent;
(D) a drying tank;
(E) a take-up roller;
having
A recovery device characterized in that the dissolution tank is composed of a plurality of dissolution tanks having different tank lengths, and the tank lengths of the dissolution tanks are configured to become shorter toward the winding roller . The recovery device according to claim 5 , wherein the dissolving tank and the drying tank include a plurality of rollers for sequentially sending out the thermoplastic resin film supplied from an unwinding roller.

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