KR102299091B1 - Apparatus and method for supplying solution, solution film-forming method - Google Patents

Abstract

A solution supply method and apparatus, and a solution film forming method are provided for suppressing leakage of a polymer solution or cavitation in a supply pump disposed downstream of a delivery pump.
The dope supply apparatus 13 is equipped with the tank 17, the delivery pump 18, the pressure gauge 22, the supply pump 21, the adjustment valve 23, and the controller 24, The dope 11 is a film It is supplied to the manufacturing apparatus 14. The dope 11 in the tank 17 is delivered by the delivery pump 18 . A part of the sent dope 11 is returned to the tank 17 by the 2nd piping L2. Dope 11 supplied to the casting die 28 by the supply pump 21 is discharged from the casting die 28, and forms the film 12. The primary pressure of the supply pump 21 is controlled within a set range by adjusting the opening degree of the regulating valve 23 by the controller 24 based on the detection result by the pressure gauge 22 .

Description

Solution supply method and apparatus, and solution film forming method

The present invention relates to a solution supply method and apparatus, and a solution film forming method.

In the solution film forming method, a polymer solution in which a polymer is dissolved in a solvent is cast on a cast support to form a cast film, the cast film is peeled off in a state containing a solvent to form a film, and the film is dried. is a manufacturing method of When manufacturing a long film by this method, a polymer solution is continuously discharged toward a support body from a casting die.

A polymer solution is prepared by melt|dissolving a polymer in a solvent, and is stored in storage parts, such as a tank, until it is provided for use. The storage part and the casting die are connected through piping, and the polymer solution is sent toward the casting die by the pump (discharge pump) for delivery from the storage part.

Fluctuation of the flow rate at which the polymer solution is supplied to the casting die changes the thickness of the film. Therefore, while manufacturing a long film, it is calculated|required to suppress the fluctuation|variation of the flow volume of the polymer solution supplied to a casting die as much as possible. Moreover, when replacing the manufacturing object of a film with another type from which thickness differs, it is calculated|required to adjust the flow volume of the polymer solution supplied to a casting die so that the thickness of the film after replacement may be expressed reliably.

For example, in the method described in Japanese Unexamined Patent Application Publication No. 2008-068440, two delivery pumps are arranged in parallel on the downstream side of the reservoir in order to replace the production target of the film with another type having a different thickness without stopping the film production line. and change from one delivery pump to the other delivery pump. In the method disclosed in Japanese Patent Laid-Open No. 2008-068440, the flow rate of one side of the delivery pump is gradually decreased and the flow rate of the other side is increased gradually from the start to the end of replacement, Keep the flow rate by both delivery pumps approximately constant. And the pressure fluctuation of the outlet piping is suppressed by controlling the flow volume of the return piping extending from the downstream outlet piping of the parallel two piping in which the delivery pumps were respectively arrange|positioned to the upstream inlet piping.

In addition, when a plurality of films having different compositions are replaced and manufactured, a plurality of polymer solutions having different compositions are used interchangeably. For example, in the manufacturing method of the film described in Unexamined-Japanese-Patent No. 2010-240875, for example, the 1st and 2nd polymer solutions different in composition are respectively stored in the storage part connected in parallel, These two The first polymer solution is replaced with the second polymer solution by replacing the delivery pump provided at each downstream of the reservoir. A return pipe for returning the polymer solution to the upstream side is provided in each parallel pipe in which the reservoir and the delivery pump are provided. In the method of Japanese Patent Laid-Open No. 2010-240875, one of the valves provided in each of these two return pipes is fully expanded and the other is gradually decreased, thereby changing the supply pump while adjusting the flow rate supplied to the cast die. .

However, even when the polymer solution is delivered from the storage part at a constant flow rate by a delivery pump as in Japanese Unexamined Patent Application Publication No. 2008-068440 and Japanese Unexamined Patent Application Publication No. 2010-240875, there is a pressure loss in the pipe leading to the casting die, The pressure loss changes with time. Under the influence of this pressure loss and its change with time, the flow rate of the polymer solution supplied to the flexible die is changed, thereby affecting the thickness of the film. Moreover, in the method of Unexamined-Japanese-Patent No. 2010-240875, even if it uses a return piping, it cannot respond to the pressure loss in piping leading to a casting die, and its change. Then, it is effective in order to manufacture the film of a desired thickness to provide the pump (supply pump) for supplying a polymer solution by a fixed flow rate downstream of a sending pump.

However, when a feed pump is used, so-called cavitation occurs in which, for example, a polymer solution leaks from, for example, a gear portion of the feed pump, or bubbles are mixed in the polymer solution from the feed pump.

Then, an object of this invention is to provide the solution supply method and apparatus, and the solution film forming method which suppress that a polymer solution leaks or cavitation occurs in the said supply pump.

The solution supply method of the present invention includes a delivery step (step A), a supply step (step B), a pressure detection step (step C), a return step (step D), and a pressure control step (step E). and the polymer solution is supplied to a discharge unit for discharging the polymer solution in which the polymer is dissolved in the solvent. In step A, the polymer solution stored in the storage unit is delivered by a delivery pump. In step B, the polymer solution delivered from the storage unit is supplied at a constant flow rate to the discharge unit by a supply pump provided downstream of the discharge pump. Step C detects the pressure on the primary side of the supply pump. In step D, a part of the polymer solution from the delivery pump is returned to the reservoir by a second pipe that branches from the first pipe extending from the delivery pump to the feed pump and connects to the reservoir. In step E, the pressure on the primary side is controlled within a preset constant range by adjusting the opening degree of the regulating valve provided in the second pipe based on the detection result in step C.

When a discharge part is a casting die of the film manufacturing apparatus which manufactures a film by solution film forming, the said solution supply method is effective especially.

When the solution supply method further includes an addition step (step F), hardening is large. In step F, the additive liquid in which the additive contained in a film is melt|dissolved in the solvent is added to the polymer solution in 1st piping by the 3rd piping connected to 1st piping.

Said solution supply method is effective when adjusting the flow volume of an additive liquid by the valve for addition provided in the 3rd piping.

The above solution supply method is effective even when the concentration of the solid content of the additive solution and the polymer solution is the same.

The above solution supply method is effective even if the type of the additive liquid is changed when the type of the film to be manufactured is replaced.

The solution supply apparatus of the present invention includes a storage unit, a delivery pump, a first pipe, a supply pump, a pressure gauge, a second pipe, a control valve, and a controller, and includes a polymer solution in which a polymer is dissolved in a solvent. A polymer solution is supplied to the discharge unit for discharging the . The storage unit stores the polymer solution. The delivery pump delivers the polymer solution from the storage unit. The first pipe guides the polymer solution from the reservoir. The supply pump is provided downstream of the delivery pump through the first pipe, and supplies the polymer solution to the discharge part at a constant flow rate. The pressure gauge detects the pressure on the primary side of the supply pump. The second pipe branches off from the first pipe and connects to the reservoir, and returns a part of the polymer solution from the delivery pump to the reservoir. The adjustment valve is provided in the 2nd piping, and adjusts the return flow volume of the polymer solution to the storage part. The controller controls the above-mentioned primary-side pressure within a predetermined range by adjusting the opening degree of the regulating valve based on the detection result by the pressure gauge.

When a discharge part is a casting die of the film manufacturing apparatus which manufactures a film by a liquid film, the said solution supply apparatus is effective especially.

It is preferable to provide a third pipe for adding an additive solution in which an additive to be contained in the film is dissolved in a solvent to the polymer solution. The third pipe is connected to the first pipe.

It is preferable that 3rd piping has the valve for addition which adjusts the flow volume of an additive liquid.

The solution supply device is effective when the concentration of the solid content of the additive solution and the polymer solution is equal to each other.

The solution supply device is effective when the third pipe guides the first additive solution and the second additive solution to be added to the polymer solution by replacing each other according to the type of film to be manufactured.

The solution film forming method of the present invention includes the above-mentioned step A, the supply step (step G), the step C described above, the casting step (step H), the peeling step (step I), and the drying step (step J). A film is manufactured by continuously discharging and drying the polymer solution in which the polymer is dissolved in the solvent from the casting die, including the above-mentioned D step and the above-mentioned E step. G-step supplies the polymer solution sent out from the storage part to the casting die at a fixed flow rate by the supply pump provided downstream of the sending pump. H step continuously discharges a polymer solution from a casting die on a casting support body, and forms a casting film. I step peels a cast film from a cast support body. The J step dries the film formed by the peeling in the I step.

The above-mentioned solution film forming method is effective when provided with the above-described F step, and is particularly effective when the flow rate of the additive solution is adjusted by the valve for addition provided in the third pipe. In addition, the above solution film forming method is effective when the additive liquid and the polymer solution have the same solid content concentration, when the types of films to be manufactured are exchanged, or when the types of the additive liquid are replaced.

ADVANTAGE OF THE INVENTION According to this invention, the supply pump which supplies a polymer solution at a fixed flow rate to a casting die WHEREIN: It can suppress that a polymer solution leaks or cavitation generate|occur|produces.

The above object and advantage will be easily understood by those skilled in the art by reading the detailed description of the preferred embodiment with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS It is the schematic of the solution film forming facility which implemented this invention.
Fig. 2 is a flow diagram for controlling the pressure on the primary side of the feed pump.
Fig. 3 is a schematic diagram of a solution supply device according to another embodiment of the present invention.
Fig. 4 is a schematic diagram of a solution supply device according to another embodiment of the present invention.

<First embodiment>

The solution film forming facility 10 shown in FIG. 1 is for manufacturing the film 12 from the dope 11, and is equipped with the dope supply apparatus 13 and the film manufacturing apparatus 14. As shown in FIG. Dope 11 is a polymer solution in which a polymer is dissolved in a solvent. In this embodiment, although TAC (cellulose triacetate) is used as a polymer and the mixture of dichloromethane, methanol, and butanol is used as a solvent, a polymer and a solvent are not limited to these. Details of the polymer and solvent that can be used in the present invention will be described later. Various additives, such as a plasticizer, a ultraviolet absorber (henceforth a UV absorber), and a retardation control agent, may be contained in dope 11.

The dope supply apparatus 13 is for supplying dope 11 to the film manufacturing apparatus 14 continuously. The dope supply apparatus 13 is equipped with the tank 17, the delivery pump 18, the supply pump 21, the pressure gauge 22, the adjustment valve 23, and the controller 24. It is preferable that the dope supply apparatus 13 is further equipped with the filter 25 like this embodiment, and in this embodiment, the filter 25 and the casting die 28 of the film manufacturing apparatus 14 are connected, have. In addition, the filter 25 may be arrange|positioned rather than the pressure gauge 22 upstream.

The tank 17, the delivery pump 18, the pressure gauge 22, the supply pump 21, the filter 25, and the casting die 28 which are arrange|positioned in order from the upstream are connected by the 1st piping L1. connected. The first pipe L1 is branched between the delivery pump 18 and the pressure gauge 22 , and the second pipe L2 branched from the first pipe L1 is connected to the tank 17 . The adjustment valve 23 is provided in this 2nd piping L2. In addition, in the following description, the position where the 2nd pipe|tube L2 branches from the 1st pipe|tube L1 is called a branch position, and the code|symbol PB is attached|subjected.

The tank 17 is a storage part that stores the dope 11 . In this tank 17, the flow volume of the dope 11 sent out from the tank 17 (henceforth a delivery flow volume), and the flow volume of the dope 11 in the 2nd piping L2 (henceforth return flow volume) It also functions as an independent part that makes it independent.

The delivery pump 18 is for sending out the dope 11 from the tank 17 . The delivery pump 18 applies pressure to the dope 11, and sends it (pressure-feeding). In this embodiment, a gear pump is used as the delivery pump 18 . However, the delivery pump 18 is not limited to this, for example, a diaphragm pump, a can pump, etc. may be sufficient. The flow path of the dope 11 sent out from the tank 17 by the delivery pump 18 is the 1st piping L1 extended to the supply pump 21 and the film manufacturing apparatus 14, and the 1st piping L1 ) to the second pipe L2 branched from, and divided at the branch position PB.

The supply pump 21 is for supplying the dope 11 to the casting die 28 at a fixed flow volume. As the supply pump 21, a gear pump is used. Thereby, the supply pump 21 supplies the dope 11 guided to the 1st piping L1 by the delivery pump 18 to the delivery casting die 28 at a fixed flow volume. Flow rate (henceforth a supply flow volume) of dope 11 supplied to casting die 28 with supply pump 21 is quantity in unit time of dope 11 discharged from casting die 28 determined based on Hereinafter, the quantity per unit time of dope 11 discharged from casting die is called discharge flow volume.

The filter 25 is for filtering the dope 11 sent out by the supply pump 21, and removing a foreign material from the dope 11. As the filter 25, a metal filter is used in this embodiment. However, the filter 25 is not limited to this, For example, filter paper, a leaf filter, etc. may be used. The dope 11 which passed the filter 25 is supplied to the casting die 28 of the film manufacturing apparatus 14. As shown in FIG.

The second pipe L2 branched from the first pipe L1 downstream of the delivery pump 18 is for returning a part of the dope 11 from the delivery pump 18 to the tank 17 . The adjustment valve 23 is for adjusting the flow rate of return flow, ie, the dope 11 returned to the tank 17. The adjustment valve 23 can adjust an opening degree, and by setting it as hot air, a part of dope 11 of the 1st piping L1 is returned to the tank 17, and the return flow volume is adjusted by adjustment of an opening degree. Moreover, the regulating valve 23 outputs the opening degree to the controller 24 .

The pressure gauge 22 is for detecting the pressure PA of the primary side of the supply pump 21, ie, the pressure of the dope 11 which enters the supply pump 21. As shown in FIG. The pressure on the primary side of the supply pump 21 is hereinafter referred to as primary side pressure. The pressure gauge 22 is provided between the branch position PB and the supply pump 21 . Thus, in this embodiment, although the pressure gauge 22 is provided in the 1st piping L1 upstream from the supply pump 21, it is not limited to this aspect. For example, the pressure gauge 22 may be provided inside the supply pump 21 .

The controller 24 is for controlling the primary-side pressure PA within a predetermined range (hereinafter referred to as a set range) PS. The controller 24 includes a storage unit (not shown) and a calculation unit (not shown). The storage unit stores the opening degree of the regulating valve 23 and the inputted setting range PS. The calculation unit calculates the opening degree of the regulating valve 23 at which the primary pressure PA falls within the set range PS, based on the detection result in the pressure gauge 22 and the setting range PS stored in the storage unit, , adjust the control valve (23). Specifically, the difference between the setting range PS stored in the storage unit and the detection result in the pressure gauge 22 is obtained, and from the difference, the regulating valve 23 in which the primary pressure PA is within the set range PS. ) is calculated, and the control valve 23 is adjusted. In this way, based on the detection result by the pressure gauge 22 , the controller 24 controls the control valve 23 so that the primary pressure PA is within the set range PS by the storage unit and the calculation unit. adjust the opening

The film manufacturing apparatus 14 is equipped with the casting unit 31, the tenter 32, the roller dryer 33, and the winder 34 in order from an upstream. The casting unit 31 includes a band 40 as a flexible support formed in an annular shape, a pair of rollers 41 supporting the band 40 and running in the longitudinal direction, and a casting die 28 and , a peeling roller 42 is provided. At least one of the pair of rollers 41 rotates in the circumferential direction, and by this rotation, the band 40 wound around the pair of rollers 41 circulates in the longitudinal direction. Although the casting die 28 is arrange|positioned above one of a pair of rollers 41 in this example, even if it arrange|positions above the band 40 between one of a pair of rollers 41 and the other, do.

The casting die 28 is a discharge part which continuously discharges the supplied dope 11 from the discharge port 28a which opposes the band 40. By continuously discharging the dope 11 to the band 40 during running, the dope 11 is cast on the band 40 , and the cast film 43 is formed on the band 40 . In FIG. 1, code|symbol PC is given to the position (henceforth a casting position) where dope 11 contacts the drum 41 and the casting film 43 begins to form.

The pair of rollers 41 is provided with a temperature controller (not shown) which adjusts the circumferential surface temperature. By the roller 41 for adjusting the circumferential surface temperature, the flexible membrane 43 through the band 40 is temperature adjusted. In the case of the so-called dry gelation system in which the cast film 43 is heated and hardened by promoting drying (gelling), the peripheral surface temperature of the roller 41 is, for example, within the range of 10°C or more and 40°C or less. Moreover, in the case of the so-called cooling gelation system which hardens by cooling the cast film 43, the circumferential surface temperature of the roller 41 shall be in the range of -10 degreeC or more and 5 degrees C or less. By such gelation, the cast film 43 is hardened to such a degree that it can be conveyed.

Moreover, as a flexible support body, you may replace with the band 40 and may use a drum (not shown). In this case, the cast film 43 is formed on the main surface by providing a drive mechanism in a drum and rotating it in the circumferential direction. When using a drum as a cast support body, a drum shall be provided with the temperature controller (not shown) which adjusts the circumferential surface temperature, If the temperature of the cast film 43 is adjusted by adjusting the circumferential surface temperature of the drum, do.

Regarding dope 11 from the casting die 28 to the band 40, a so-called bead, a pressure reduction chamber (not shown) is provided upstream in the traveling direction of the band 40. This decompression chamber sucks the atmosphere of the upstream area of the discharged dope 11, and reduces this area. Moreover, you may provide the blower (not shown) for opposing the band 40 and promoting drying of the cast film 43.

After hardening the cast film 43 on the band 40 to the extent that conveyance to the tenter 32 is possible, it peels from the band 40 in the state containing a solvent. The peeling roller 42 is for continuously peeling the cast film 43 from the band 40. The peeling roller 42 supports the film 12 formed by peeling from the band 40 from below, for example, and maintains the peeling position PP where the cast film 43 peels from the band 40 constant. . The peeling method may be either a method of pulling the film 12 to the downstream side, a method of rotating the peeling roller 42 in the circumferential direction, or the like.

In the case of a dry gelation system, peeling from the band 40 is performed while the solvent content rate of the cast film 43 exists in the range of 20 mass % or more and 50 mass % or less. In addition, in this specification, the solvent content rate (unit; %) is a value on a dry basis, and, specifically, when the mass of the solvent is x and the mass of the film 12 is y, {x/(yx)} It is a percentage calculated by ×100.

As described above, the casting unit 31 forms the film 12 from the dope 11 . As for the band 40, casting|flow_spread of the dope 11 and peeling of the casting|flow_spreading film 43 are repeatedly performed by circulating and traveling through the casting position PC and the peeling position PP.

In the conveyance path between the casting|flow_spreading unit 31 and the tenter 32, you may arrange|position the blower (not shown) for advancing drying of the film 12. The film 12 formed by peeling is guided to the tenter 32 . The tenter 32 is provided with the clip 46 which grips the side part of the elongate film 12, a pair of rails (not shown), and a chain (not shown). In place of the clip 46 , a plurality of pins (not shown) are placed in an upright posture on the upper surface of the base, and pins holding the film 12 by piercing individual pins to the sides of the film 12 . A plate (not shown) may be used.

A rail is provided on the side of the conveyance path of the film 12, and a pair of rails is spaced apart and arrange|positioned. The chain is mounted so as to be movable along a rail over a driving sprocket and a driven sprocket (not shown). The clips 46 are attached to the chain at predetermined intervals, and by rotation of the driven sprocket, the clips 46 circulate along the rail. The clip 46 starts holding|maintenance of the film 12 which has been guided in the vicinity of the entrance of the tenter 32, moves toward the exit, and releases holding|maintenance in the vicinity of the exit. The clip 46 released from holding moves again to the vicinity of the entrance to hold the newly guided film 12 . In this way, the clip 46 grips each side of the film 12 and conveys it in the longitudinal direction.

The tenter 32 is provided with a blower 47 above the conveyance path of the film 12 . An outlet (not shown) through which the drying gas flows is formed in the lower surface of the blower 47 , and the drying gas is blown out toward the passing film 12 . Moreover, you may provide the blower which has the same structure below the conveyance path of the film 12.

The roller dryer 33 includes a plurality of rollers 48 and an air conditioner (not shown). A plurality of rollers 48 support the film 12 on the main surface. The film 12 is wound around a roller 48 and conveyed. The air conditioner adjusts the temperature, humidity, etc. inside the roller dryer 33 . The winder 34 is for winding the film 12 in roll shape.

The above-mentioned setting range PS with respect to the primary side pressure PA is calculated|required before starting manufacture of the film 12 in this embodiment, An example of the calculating|requiring method is as follows. In addition, the lower limit of the setting range PS is set to P1, and the upper limit is set to P2. That is, the setting range PS is the range of P1 or more and P2 or less.

The first pipe L1 between the supply pump 21 and the filter 25 is branched, and the branch pipe (not shown) is connected to the tank 17 . The observation window for observing whether or not bubbles exist in the dope 11 which flows through an internal flow path is provided in this branch piping. A valve (not shown) is provided between the branch position of the first pipe L1 provided with this branch pipe and the filter 25, and this valve and the adjustment valve 23 are closed. The delivery pump 18 and the feed pump 21 are driven, and in the state which made the flow volume of the dope 11 by the feed pump 21 constant, the delivery flow volume is changed, and the primary side pressure PA for every delivery flow volume. to detect Dope 11 poured during detection is returned to the tank 17 by said branch piping. The flow rate of the dope 11 by the supply pump 21 in this detection should just be constant, for example, it may be made constant with the above-mentioned supply flow volume, and may be made constant with the flow volume different from the above-mentioned supply flow volume.

When primary-side pressure PA becomes too low and a bubble is confirmed in the dope 11 which flows in the said branch piping, when setting primary-side pressure PA as PAL, PALx1.1 is set as the lower limit P1. When the primary pressure PA at which the primary pressure PA becomes too high and the dope 11 leaks from, for example, the gear portion of the supply pump 21 is set to PAH, PAH x 0.9 is set as the upper limit P2. In this way, while making the delivery flow rate small, PAL which is the primary pressure (PA) at which bubbles start to be confirmed in the dope 11 multiplied by 1.1 is P1, and the delivery flow rate is increased from the supply pump 21 to the dope 11 ) multiplied by 0.9, PAH, which is the primary pressure (PA) at which leakage starts, is set as P2. As described above, the setting range PS is obtained. Moreover, since P1 and P2 differ with the dope 11 to be used, it sets with respect to the dope 11 to be used. Therefore, P1 and P2 are set with respect to each of the dope 11 to be used when replacing and providing to the film manufacturing apparatus 14 by replacing the some dope 11 different from each other. In addition, since P1 and P2 differ depending on the supply pump to be used, they are set for each of the supply pumps 21 to be used.

As for the lower limit P1 in PS, it is more preferable to set it as PAL*1.15. As for the upper limit P2, it is more preferable to set it as PAHx0.85.

The operation of the above configuration will be described. Dope 11 prepared in advance and stored in the tank 17 is sent out at a constant delivery flow rate from the tank 17 by the delivery pump 18 (sending step), and flows through the 1st piping L1. The sent dope 11 is guided into the 1st pipe L1 toward the film manufacturing apparatus 14 at the branch position PB, and is guided into the 2nd pipe L2 toward the tank 17 ( retrace step). Dope 11 guided in the 1st piping L1 toward the casting die 28 is fixed to the casting die 28 of the film manufacturing apparatus 14 through the filter 25 by the supply pump 21 It is supplied at a flow rate (supply step). By using the supply pump 21, compared with the sending only by the sending pump 18, since the pressure loss in the 1st piping L1 is suppressed, the dope 11 is a more highly accurate constant flow volume. is supplied to the flexible die (28). The filter 25 removes foreign substances from the dope 11 by filtering the dope 11 which goes to the casting die 28.

As shown in FIG. 2 , the pressure gauge 22 detects the primary pressure PA (pressure detection step) and outputs the detection result to the calculation unit of the controller 24 . The calculation unit of the controller 24 compares the input detection result with the above-described setting range PS stored in the storage unit, and the primary pressure PA of the detection result is within the setting range PS, that is, P1 It is checked whether it is within the range of more than P2 or less. When the primary pressure PA is within the set range PS, the rotation speed of the delivery pump 18 and the supply pump 21 and the opening degree of the regulating valve 23 are maintained without changing.

When the primary pressure PA is outside the set range PS, the controller 24 checks whether the primary pressure PA is higher than the upper limit value P2 or lower than the lower limit value P1. In the case where the primary pressure PA is higher than the upper limit value P2 (PA>P2), when the opening degree of the regulating valve 23 is not open, the controller 24 makes the opening degree of the regulating valve 23 larger than the present. do. Since the return flow volume becomes large because the opening degree of the regulating valve 23 becomes larger, and the flow volume of the dope 11 which flows into the supply pump 21 by this becomes smaller, primary side pressure PA falls. The lowered primary pressure PA is newly detected by the pressure gauge 22, and when this new detection result is within the set range PS, the rotation speed of the delivery pump 18 and the supply pump 21, and the adjustment valve The opening degree of (23) is maintained without changing. On the other hand, when the new detection result is higher than the upper limit value P2 (PA>P2) and the opening degree of the regulating valve 23 is not open, the controller 24 makes the opening degree of the regulating valve 23 larger, so that the supply pump (21) further lower the primary pressure (PA). In this way, when the primary pressure PA is higher than the upper limit value P2 and the opening degree of the regulating valve 23 is not open, the regulating valve 23 is adjusted so that the opening degree becomes larger, and by this pressure gauge 22 By repeating the detection and adjustment by the controller 24, the primary pressure PA is made equal to or less than the upper limit P2.

When the primary pressure PA is higher than the upper limit P2 and the opening degree of the regulating valve 23 is open, since the opening degree of the regulating valve 23 cannot be made larger, the controller 24 controls the delivery pump By changing the rotation speed of (18), the delivery flow rate is made smaller than the present. When the sending flow rate becomes small, the return flow volume and the flow volume of the dope 11 which flow to the supply pump 21 become smaller. Since the flow volume of the dope 11 which flows into the supply pump 21 becomes small, primary side pressure PA falls. The pressure gauge 22 detects a new primary pressure PA, and when this new detection result is within the set range PS, the rotation speed of the delivery pump 18 and the supply pump 21, and the adjustment valve 23 does not change the degree of opening of On the other hand, when the new detection result is still higher than the upper limit value P2, the controller 24 makes the opening degree of the regulating valve 23 larger, or Make the output flow rate smaller. In this way, by repeating the detection of the pressure gauge 22 and the adjustment by the controller 24, the primary pressure PA is set to be equal to or less than the upper limit P2.

When the primary pressure PA is lower than the lower limit P1 and the opening degree of the regulating valve 23 is not close, that is, when it is open, the controller 24 sets the opening degree of the regulating valve 23 more than the present. make it small When the opening degree of the regulating valve 23 becomes smaller, the return flow rate becomes small, and since the flow volume of the dope 11 which flows into the supply pump 21 by this becomes larger, primary-side pressure PA becomes high. The increased primary pressure PA is newly detected by the pressure gauge 22, and when this new detection result is within the set range PS, the rotation speed of the delivery pump 18 and the supply pump 21 and the adjustment valve The opening degree of (23) is maintained without changing. On the other hand, when the new detection result is lower than the lower limit value P1 and the opening degree of the regulating valve 23 is not close, the controller 24 makes the opening degree of the regulating valve 23 smaller, thereby lowering the primary pressure PA. make it high In this way, when the primary pressure PA is lower than the lower limit P1 and the opening degree of the regulating valve 23 is not close, the opening degree of the regulating valve 23 is adjusted to be smaller, and by this pressure gauge 22 By repeating detection and adjustment by the controller 24, the primary pressure PA is made equal to or more than the lower limit P1.

When the primary pressure PA is lower than the lower limit P1 and the opening degree of the regulating valve 23 is close, since the opening degree of the regulating valve 23 cannot be made smaller, the controller 24 controls the delivery pump By changing the rotation speed of (18), the delivery flow rate is made larger than the present. When the sending flow rate becomes large, the return flow rate and the flow volume of the dope 11 which flow into the supply pump 21 become large. When the flow volume of the dope 11 which flows into the supply pump 21 becomes larger, primary-side pressure PA becomes higher. The pressure gauge 22 detects a new primary pressure PA, and when this new detection result is within the set range PS, the rotation speed of the delivery pump 18 and the supply pump 21, and the adjustment valve 23 does not change the degree of opening of On the other hand, when the new detection result is still lower than the lower limit P1, the controller 24 makes the opening degree of the regulating valve 23 smaller, or Increase the output flow rate. In this way, by repeating the detection of the pressure gauge 22 and the adjustment by the controller 24, the primary pressure PA is made equal to or greater than the lower limit P1.

As described above, in the case where the opening degree of the regulating valve 23 is not open and not closed, the return flow rate is adjusted by adjusting the opening degree of the regulating valve 23, and the primary side pressure PA is described above. Control within the setting range (PS) of In addition, in the case where the opening degree of the regulating valve 23 is open and close, the primary-side pressure PA is controlled within the above-mentioned setting range PS by adjustment of the delivery flow rate. Thus, since primary side pressure PA is controlled (pressure control step), in the supply pump 21, leakage of dope 11 does not generate|occur|produce in a gear etc., and cavitation does not generate|occur|produce either.

Moreover, since the opening degree of the regulating valve 23 is open, when adjusting the delivery flow rate, the regulating valve 23 capable of subsequent control of the primary pressure PA can be performed by adjusting the opening degree of the regulating valve 23 . ), you may adjust the sending flow rate smaller until it becomes the adjustable range. In addition, since the opening degree of the regulating valve 23 is close, also when adjusting the sending flow rate, you may adjust the sending flow volume larger until it becomes the adjustable range of the said regulating valve 23 similarly.

Dope 11 supplied at a constant flow rate by the supply pump 21 is continuously discharged from the casting die 28 toward the band 40 traveling. Thereby, the cast film 43 is continuously formed on the band 40 (casting step). The cast film 43 is hardened by temperature adjustment on the band 40, etc., and is peeled from the band 40 in the peeling position PP in the state containing a solvent (peeling step).

The film 12 formed by peeling the cast film 43 from the band 40 is guided to the tenter 32, and is conveyed in the state hold|gripped by the side part by the clip 46. Drying of the film 12 in conveyance advances with the drying gas blown out from the blower 47. As shown in FIG. The film 12 is guided to the roller dryer 33 by releasing the grip by the clip 46 at the downstream end of the tenter 32 . While being supported by each roller 48 of the roller dryer 33 and being conveyed, the film 12 is further dried. Thus, the drying step of drying the film 12 is performed by both the tenter 32 and the roller dryer 33 . The dried film 12 is wound in a roll shape in a winder 34 . As mentioned above, in the solution film forming installation 10, the film 12 is manufactured from the dope 11. Moreover, a slitter (not shown) may be arrange|positioned rather than the tenter 32 downstream, and you may remove the holding trace of the film 12 by the clip 46. As shown in FIG. Moreover, in this embodiment, when making the mat agent contain in the film 12, the dispersion liquid which disperse|distributed the mat agent to the 1st piping L1 between the supply pump 21 and the filter 25 in the dispersion medium. By supplying, it is preferable to add a mat agent in dope 11.

<Second embodiment>

The additive to be contained in the film 12 may be added to the dope in the 1st piping L1, and you may supply to the film manufacturing apparatus 14. The dope supply apparatus 51 shown in FIG. 3 adds the additive liquid 53 to the reference dope 52 as a polymer solution in which the polymer is melt|dissolved in the solvent, Dope for casting|flow_spread (hereinafter referred to as casting dope) 56 ) and supplying this casting|flow_spread dope 56 to the film manufacturing apparatus 14 similarly to the dope supply apparatus 13. In FIG. 3, the code|symbol similar to FIG. 1 is attached|subjected about the same apparatus and member as what exists in the solution film forming facility 10 of FIG. 1, and description is abbreviate|omitted.

The reference dope 52 is used in common, when manufacturing several types of films. In this embodiment, although TAC and the mixture of dichloromethane, methanol, and butanol are used as a polymer of the reference|standard dope 52 and a solvent, a polymer and a solvent are not limited to this. The additive liquid 53 is a solution in which an additive is dissolved in a solvent. Although the additive in this embodiment is a plasticizer, a UV absorber, a retardation controlling agent, etc. may be sufficient instead of this or in addition.

The dope supply apparatus 51 is a structure provided with the 3rd piping L3 in the dope supply apparatus 13, Furthermore, it is equipped with the static mixer 57 and the valve 58 for addition like this embodiment. It is more preferable to The third pipe L3 is for guiding the additive liquid 53 . The third pipe L3 is connected to the first pipe L1 between the delivery pump 18 and the supply pump 21 . When the pressure gauge 22 is provided in the first pipe L1 upstream of the supply pump 21 as in the present embodiment, the first pipe L1 between the delivery pump 18 and the pressure gauge 22 . , the third pipe L3 is connected. In FIG. 3, the code|symbol PJ is attached|subjected to the connection position of the 1st pipe|tube L1 and the 3rd pipe|tube L3.

The valve 58 for addition is for adjusting the flow volume of the additive liquid 53 . The valve 58 for addition is provided in the 3rd pipe|tube L3, and the flow volume of the additive liquid 53 added with respect to the reference|standard dope 52 which flows through the 1st pipe|tube L1 by adjustment of the opening degree (hereinafter, addition) flow rate).

Although the density|concentration (henceforth solid content concentration) of the solid content of the reference|standard dope 52 and the additive liquid 53 may mutually differ, it is preferable to make mutually same, and it is like this also in this embodiment. The solid content constitutes the film 12 , that is, a component of the film 12 . The solid content of the reference dope 52 in this embodiment is a polymer, and the solid content of the additive liquid 53 is a plasticizer. In addition, "the same" is not limited to strictly the same thing, and it may be within 0.1%, and if it is within 0.05%, it is more preferable. In the case of manufacturing the film 12, the solid content concentration in the reference dope 52 is in the range of 15% or more and 25% or less, whereas, conventionally, the solid content concentration in the additive liquid is 40% or more and 50% or less. It exists in the range of and was very high compared with the solid content concentration of the reference|standard dope 52. On the other hand, in this embodiment, the solid content concentration of the additive liquid 53 is making it the same as the solid content concentration of the reference|standard dope 52, and is very lower than the conventional additive liquid. Thereby, even if it changes the flow volume of the additive liquid 53 as mentioned later, since solid content concentration in the casting dope 56 does not change by this, casting|flow_spreading can be continued stably. In addition, the above solid content concentration (unit: mass %) is calculated by M1/(M1+M2)×100 when the mass of the solid content is M1 (unit: g) and the mass of the solvent is M2 (unit: g). is the value

The static mixer 57 is for mixing the reference dope 52 and the additive liquid 53 in a uniform state. The static mixer 57 is provided in the first pipe L1 between the connection position PJ and the supply pump 21 . When the pressure gauge 22 is provided in the first pipe L1 upstream of the delivery pump 18 as in the present embodiment, the static mixer 57 is disposed between the connection position PJ and the pressure gauge 22 . It may be provided in the first pipe L1 of As the static mixer 57, a static mixer, a thru-der mixer, etc. are mentioned. Moreover, although the static mixer 57 is set to one in this embodiment, when the mixed state of the reference|standard dope 52 and the additive liquid 53 is insufficient, you may increase the number of the stationary mixers 57.

The setting range PS of the primary side pressure in this embodiment is set using the casting|flow_spread dope 56. Since the lower limit P1 and the upper limit P2 of the setting range PS differ with the softness dope 56, they are calculated|required according to the softness|flexibility dope 56 to be used. Therefore, P1 and P2 are set with respect to each of the casting|flow_spreading dope 56 to be used, when it replaces and provides to the film manufacturing apparatus 14 by replacing the some different flexible dope 56. As shown in FIG. Moreover, when manufacture is started and the opening degree of at least one of the control valve 23 and the valve 58 for addition is adjusted, the composition of the casting|flow_spread dope 56 may change. However, in this case, it is not necessary to change the setting range PS set before the start of manufacture during manufacture.

The operation of the above configuration will be described. The reference dope 52 prepared in advance and stored in the tank 17 is sent out at a constant delivery flow rate from the tank 17 by the delivery pump 18 (sending step). The sent out reference dope 52 is divided into what is guided in the 1st piping L1 toward the casting die 28 at the branch position PB, and is guided into the 2nd piping L2 (return step).

The additive liquid 53 guided to the 3rd pipe L3 is added to the reference dope 52 guided into the 1st pipe|tube L1 from the branch position PB (addition step), The static mixer 57 By mixing, a flexible dope 56 in which a polymer and an additive are mixed in a uniform state is obtained. Thus, the additive liquid 53 is added to the reference|standard dope 52 in the 1st piping L1. Therefore, when changing the kind of the film 12, what is necessary is just to replace the additive liquid 53 with another kind, and to adjust the flow volume of the additive liquid 53 with the valve 58 for addition. According to this method, it is not necessary to prepare dope for each kind of the film 12 to manufacture and to store. Moreover, when replacing the kind of the film 12 to manufacture, it is not necessary to change the whole piping of a dope supply apparatus with new dope, The 1st piping L1 downstream from the 3rd piping L3 inside and the connection position PJ. ) is sufficient to replace the inside. The casting dope 56 is supplied to the casting die 28 through the filter 25 by the supply pump 21 . On the other hand, the reference dope 52 guided to the second pipe L2 returns to the tank 17 .

When the primary pressure PA detected by the pressure gauge 22 is within the set range PS, the rotation speed of the delivery pump 18 and the supply pump 21 and the opening degree of the regulating valve 23 are not changed. , keep When the primary pressure PA is not within the set range PS, the controller 24 controls the primary pressure PA within the set range PS as in the first embodiment. That is, in the case where the opening degree of the control valve 23 is not open and not close, the return flow volume of the reference|standard dope 52 is adjusted by adjustment of the opening degree of the control valve 23, and, by this, the primary side pressure (PA) is controlled within the above-described setting range (PS). In addition, in the case where the opening degree of the regulating valve 23 is open and close, the primary-side pressure PA is controlled within the above-mentioned setting range PS by adjustment of the delivery flow volume of the reference|standard dope 52. Thus, since the primary side pressure PA of the supply pump 21 is controlled (pressure control step), in the supply pump 21, the leak of the flexible dope 56 does not generate|occur|produce in a gear etc., and also cavitation generate|occur|produces I never do that.

By the way, the mass ratio of an additive and a polymer is previously set as a range for every film 12 to manufacture. When the mass of the polymer in the reference dope 52 with respect to the mass of the additive in the additive liquid 53 becomes less than the range of an expectation by adjustment of a return flow volume or adjustment of a delivery flow volume, the valve for addition The opening degree of (58) is made smaller than the present. For example, by making the opening degree of the valve 58 for addition small, addition flow rate is lowered|hung within the range of 0.01 times or more and less than 1.0 times of present. Accordingly, the flow rate ratio of the additive liquid 53 and the reference dope 52 is adjusted, so that the mass of the polymer with respect to the mass of the additive is within the desired range. Thus, also when the flow volume of the additive liquid 53 is changed, the flow volume of the casting|flow_spreading dope 56 changes. However, in this case as well, since the primary pressure PA is similarly detected and controlled within the set range PS, in the supply pump 21, leakage of the flexible dope 56 does not occur in gears, etc., and also cavitation doesn't happen

In addition, since the mass ratio of an additive and a polymer is preset for every film 12 to manufacture, when using the additive liquid 53 of the same solid content concentration as the reference dope 52 like this embodiment, reference dope Compared with the conventional case of using the additive liquid of solid content concentration higher than (52), the addition flow volume of the additive liquid 53 with respect to the reference|standard dope 52 is enlarged. For example, when the solid content concentration of the additive liquid 53 is 24% compared to the case of using the additive liquid having a solid content concentration of 50%, the addition flow rate of the additive liquid 53 added to the reference dope 52 is do it more than twice. Even when the amount of addition is large in this way, the primary pressure PA is controlled so as not to exceed the set range PS and becomes large, so that leakage of the flexible dope 56 does not occur in the gear of the supply pump 21 or the like.

In addition, in the case of manufacturing by replacing the plurality of types of films 12, the type of the additive liquid 53 is changed, the flow rate of addition with respect to the reference dope 52 is changed, etc., different types of casting The dope 56 is replaced and provided to the film production apparatus 14 by the feed pump 21 . However, according to the above configuration, a set range PS is required for each of the plurality of flexible dope 56 provided for use, and the primary pressure PA is controlled within the set range PS, In the supply pump 21, leakage of the cast dope 56 does not generate|occur|produce in a gear etc., and cavitation does not generate|occur|produce either.

With the supply pump 21, casting dope 56 is supplied to the casting die 28 of the film manufacturing apparatus 14 through the filter 25 at fixed flow volume (supply step). Casting dope 11 supplied is continuously discharged from the casting die 28 toward the band 40 which travel|works, and the film 12 is manufactured like 1st Embodiment. Moreover, when making a mat agent contain in the film 12 in this embodiment, in the 1st piping L1 between the supply pump 21 and the filter 25, a mat agent to a dispersion medium as mentioned above. It is preferable to add a mat agent in the casting|flow_spread dope 56 by supplying the disperse|distributed dispersion liquid.

<Third embodiment>

Although said embodiment is an example of what is called single|mono layer casting for manufacturing the film 12 of a single|monolayer structure, in order to manufacture a film of a multilayer structure, when co-casting multiple types of dope, single|mono layer casting|flow_spreading and co-casting Even when the kite is replaced, the present invention is effective. When replacing single-layer casting and co-casting, the type of dope to be supplied is also replaced. The dope supply apparatus 71 shown in FIG. 4 is for replacing and supplying dope in order to replace and manufacture the film 12 of the single layer structure by single|mono layer casting, and the film of the multilayer structure by co-casting. In this example, co-spreading produces a film having a three-layer structure, but the number of layers of the film to be produced is not limited to three, and may be, for example, two or four or more. In FIG. 4, about the same thing as the apparatus and member shown in FIG. 1, FIG. 3, the code|symbol similar to FIG. 1, FIG. 3 is attached|subjected, and description is abbreviate|omitted.

When the dope supply apparatus 71 manufactures the film 12 of a single|monolayer structure, in the casting die 28, when manufacturing the film (not shown) of a three-layer structure, to the casting die 72, dope supply The casting die 72 makes three dope supplied independently merge inside, and discharges continuously from one discharge port 72a in the merged state. The 1st branch pipe LB1 branched from the 1st pipe L1 connected to the casting die 28 is connected to the casting die 72, and is replaced by the branch position where the 1st branch pipe LB1 branches off. A valve 73 for the dragon is provided. As for the film manufacturing facility (not shown) provided with the casting die 72, the structure other than the casting die 72 is the same as that of the film manufacturing apparatus 14.

Although the dope supply apparatus 71 of this example replaces and supplies dope to the film manufacturing apparatus provided with the film manufacturing apparatus 14 and the casting die 72, it is not limited to this. For example, in the film manufacturing apparatus 14, the dope supply apparatus 71 can be used also when changing the casting die 28 and the casting die 72, and replacing the single-layer casting|flow_spread and multilayer casting|flow_spreading. Moreover, instead of the casting die 72, a feed block which merges three dope supplied independently from the inside, and a casting die which continuously discharges dope guided in a laminated state from a feed block from one discharge port may be used do.

In this embodiment, the position where the 2nd pipe L2 branches from the 1st pipe L1 is set as a 1st branch position, code|symbol PB1 is attached|subjected, and the supply pump provided in the 1st pipe L1 is 1st supply. The pump is designated by reference numeral 21a. This 1st supply pump 21a has the same structure as the supply pump 21 of 1st and 2nd embodiment. The filter downstream of the 1st supply pump 21a of the 1st piping L1 has the same structure as the filter 25 of 1st and 2nd embodiment, In FIG. 4, the code|symbol 25a is attached|subjected.

The dope supply apparatus 71 is for making the 1st casting|flow_spread dope 75 and the 2nd casting|flow_spreading dope 76 from the reference|standard dope 52, and supplying it to the casting die 28 and the casting die 72. As 1st casting|flow_spread dope 75, what added the 1st additive liquid 77 to the reference|standard dope 52, and what added the 1st additive liquid 77 and the 2nd additive liquid 78 to the reference|standard dope 52 are have. The 1st casting|flow_spreading dope 75 obtained by adding the 1st additive liquid 77 to the reference|standard dope 52 is used for single|mono layer casting|flow_spread for manufacturing the film 12 of a single|monolayer structure, and is supplied to the casting die 28. The 1st cast dope 75 obtained by adding the 1st additive liquid 77 and the 2nd additive liquid 78 to the reference|standard dope 52 is used for co-casting for manufacturing a film (not shown) of a three-layer structure, , is supplied to the flexible die 72 . The 1st casting dope 75 obtained by adding the 1st additive liquid 77 and the 2nd additive liquid 78 to the reference dope 52 specifically forms the inner layer of the thickness direction center among the 3 layers which comprise a film. do.

The 2nd casting|flow_spreading dope 76 is the mixture of the reference|standard dope 52, the 1st additive liquid 77, and the 2nd additive liquid 78, Specifically, the 1st additive liquid 77 in the reference|standard dope 52. ) and the liquid which added the 1st additive liquid 77 to the reference|standard dope 52 to the 1st casting dope 75 which added the 2nd additive liquid 78 is added. The 2nd cast|flow_spread dope 76 is used for co-casting, and forms the layer (henceforth an outer layer) which is arrange|positioned on each surface of an inner layer, and is exposed to the outside among three layers which make a film.

In the present embodiment, the first additive solution 77 is a solution in which a plasticizer is dissolved in a solvent, and the second additive solution 78 is a solution in which a plasticizer and a UV absorber are dissolved in a solvent. This 2nd additive liquid 78 is obtained by mixing the plasticizer liquid containing a plasticizer, and the UV absorber liquid containing a UV absorber, for example. However, the 1st additive liquid 77 and the 2nd additive liquid 78 are not limited to these, For example, a retardation control agent may replace or add to a plasticizer and a UV absorber. In addition, although the plasticizer of the 1st additive liquid 77 and the 2nd additive liquid 78 is set as the same thing in this embodiment, mutually different things may be sufficient as it.

Although the solid content concentration different from the reference dope 52 may be sufficient as the 1st additive liquid 77 and the 2nd additive liquid 78, it is preferable that it is the same solid content concentration, and it is like this also in this embodiment. The solid content of the reference dope 52 in this embodiment is a polymer, the solid content of the 1st additive liquid 77 is a plasticizer, The solid content of the 2nd additive liquid 78 is a plasticizer and a UV absorber. In addition, the meaning of "the same" is the same as the above-mentioned. When manufacturing the film of a three-layer structure, while solid content concentration in the reference|standard dope 52 exists in the range of 15 % or more and 25 % or less, conventionally, solid content in a 1st additive liquid and a 2nd additive liquid Concentration was in the range of 45 % or more and 50 % or less, and was very high compared with the solid content concentration of the reference|standard dope 52. On the other hand, in this embodiment, the solid content concentration of the 1st additive liquid 77 and the 2nd additive liquid 78 is made equal to the solid content concentration of the reference|standard dope 52, The conventional 1st additive liquid and 2nd It is much lower than the additive solution. Thereby, like 2nd Embodiment, even if it changes the flow volume of the 1st additive liquid 77 and the flow volume of the 2nd additive liquid 78, 1st casting dope 75 and 2nd casting dope 76 Since the solid content concentration does not change, casting can be continued stably.

The dope supply apparatus 71 is to the dope supply apparatus 51 (refer FIG. 3) one stationary mixer, two supply pumps, two filters, 4th piping L4, 1st branch piping ( LB1) to the fourth branch pipe LB4 are added. The two static mixers are provided in series in the first pipe L1, and one of the upstream side is the first static mixer 83 and the other downstream side is the second static mixer 84.

A third pipe L3 and a fourth pipe L4 are connected to the first pipe L1, respectively. The third pipe (L3) is for guiding the first additive solution (77) to the first pipe (L1). A position where the third pipe L3 connects to the first pipe L1 is called a first connection position PJ1.

The 4th pipe L4 is for guiding the 2nd additive liquid 78 to the 1st pipe L1. A position where the fourth pipe L4 connects to the first pipe L1 is called a second connection position PJ2.

The valve 88 for addition is provided in the 3rd piping L3, and the valve 87 for addition is provided in the 4th piping L4. When the 1st additive liquid 77 is added to the reference|standard dope 52, the 1st additive liquid 77 joins the reference|standard dope 52 at the 1st connection position PJ1 of the 1st piping L1. In addition, when the 2nd additive liquid 78 is added to the reference|standard dope 52, the 2nd additive liquid 78 joins the reference|standard dope 52 at the 2nd connection position PJ2 of the 1st piping L1. do. The first static mixer 83 is between the first connection position PJ1 and the second connection position PJ2 , and the second static mixer 84 is between the second connection position PJ2 and the pressure gauge 22 . It arranges in and mixes the merged reference dope 52, the 1st additive liquid 77, and the 2nd additive liquid 78 so that it may become a uniform state, and let it be the 1st flexible dope 75.

2nd branch piping LB2 and 3rd branch piping LB3 guide 1st flexible dope 75, make 2nd flexible dope 76, and cast this 2nd flexible dope 76 by casting die 72 ) to guide you. 2nd branch piping LB2 and 3rd branch piping LB3 branch from the 1st piping L1 downstream of the pressure gauge 22, and are connected to the casting die 72. The second branch pipe LB2 is provided with a valve 91 , a second supply pump 21b , and a filter 25b . 3rd branch pipe LB3 is also comprised similarly to 2nd branch pipe LB2, and the valve 92, the 3rd supply pump 21c, and the filter 25c are provided. The valves 91 and 92 are closed when the film 12 having a single-layer structure is produced, and become open when the film having a three-layer structure is produced.

The 2nd supply pump 21b and the 3rd supply pump 21c are for supplying the 2nd casting|flow_spread dope 76 to the casting die 72 at a fixed flow volume through the filters 25b and 25c, respectively. The 2nd supply pump 21b and the 3rd supply pump 21c respectively have the same structure as the 1st supply pump 21a, ie, the same as the supply pump 21 in 1st, 2nd embodiment. is the composition

4th branch piping LB4 guides the reference dope 52 to which the 1st additive liquid 77 was added in 1st connection position PJ1 to 2nd branch piping LB2 and 3rd branch piping LB3 it is to do The fourth branch pipe LB4 is branched from the first pipe L1 between the first static mixer 83 and the second connection position PJ2. A branch position at which the fourth branch pipe LB4 branches from the first pipe L1 is called a second branch position PB2. A valve 93 is provided in the fourth branch pipe LB4 , and the fourth branch pipe LB4 branches into two downstream of the valve 93 . The branched one is connected between the valve 91 of the second branch pipe LB2 and the second supply pump 21b, and the other branched is connected to the valve 92 and the third branch of the third branch pipe LB3. It is connected between the supply pumps 21c.

In this embodiment, the pressure gauge 22 is for detecting the primary side pressure PA in all of the 1st supply pump - 3rd supply pump 21a-21c. Moreover, in the 2nd branch pipe LB2 and the 3rd branch pipe LB3, the pressure gauge (not shown) for detecting the pressure of each primary side of the 2nd supply pump 21b and the 3rd supply pump 21c is provided. , more may be provided. In this case, a pressure gauge is between the connection position which 4th branch pipe LB4 of 2nd branch pipe LB2 connects, and the 2nd supply pump 21b, and the 4th branch of 3rd branch pipe LB3. What is necessary is just to provide between the connection position to which piping LB4 connects, and the 3rd supply pump 21c, respectively. By adding these pressure gauges to the pressure gauge 22, and adjusting the opening degree of the adjustment valve 23 with the controller 24 based on these three detection results, the 1st supply pump 21a - the 3rd supply pump more reliably In (21c), leakage of the 1st flexible dope 75 and the 2nd flexible dope 76 does not generate|occur|produce in a gear etc., and cavitation does not generate|occur|produce either.

The setting range PS of the primary-side pressure PA of the 1st supply pump 21a - the 3rd supply pump 21c in this embodiment is the 1st casting|flow_spread dope 75 and the 2nd casting|flow_spread dope 76 ) is set using Moreover, the composition of the 1st flexible dope 75 and the 2nd flexible dope 76 changes because manufacture is started and the opening degree of at least any one of the adjustment valve 23 and the valves 87 and 88 for addition is adjusted. There are cases. However, in this case, it is not necessary to change the setting range PS set before the start of manufacture during manufacture.

The operation of the above configuration will be described. The reference dope 52 prepared in advance and stored in the tank 17 is sent out at a constant delivery flow rate from the tank 17 by the delivery pump 18 (sending step). The sent out reference dope 52 is guided in the 1st pipe|tube L1 toward the casting die 28 or the casting die 72 at the 1st branch position PB1, and guided into the 2nd pipe L2. It is divided into being (return step).

When manufacturing the film 12 of a single-layer structure, the valve 88 for addition shall be opened, and the 1st additive liquid 77 is used. In addition, when manufacturing the film 12 of a single-layer structure, the valve 87 for addition becomes close. Further, the valve in the first pipe L1 of the valve 73 is opened, the valve on the first branch pipe LB1 side is closed, and the valves 91 to 93 are closed. By making the valves 87 and 88 for addition into said open/close state, although the 1st additive liquid 77 is guided to the 1st piping L1, the 2nd additive liquid 78 is not guided. The 1st additive liquid 77 guided by the 3rd piping L3 is added to the reference|standard dope 52 guided in the 1st piping L1 from 1st branch position PB1 (addition step).

The reference dope 52 and the first additive liquid 77 joined at the first connection position PJ1 are mixed by the first static mixer 83 and the second static mixer 84, so that the polymer and the plasticizer are uniform. The 1st flexible dope 75 mixed in one state is obtained. 1st casting dope 75 is supplied to the casting die 28 through the filter 25a by the 1st supply pump 21a. On the other hand, the reference dope 52 guided to the second pipe L2 returns to the tank 17 .

When the primary pressure PA of the first supply pump 21a is detected by the pressure gauge 22 and the primary pressure PA is within the set range PS, the delivery pump 18 and the first supply The rotation speed of the pump 21a and the opening degree of the regulating valve 23 are maintained without changing. When the primary-side pressure PA of the first supply pump 21a is not within the set range PS, the first supply pump 21a is controlled by the controller 24 as in the first and second embodiments. control the inlet pressure (PA) within the set range (PS). That is, when the opening degree of the regulating valve 23 is in an open state instead of being expanded, the return flow rate of the reference dope 52 is adjusted by adjusting the opening degree of the regulating valve 23, and accordingly, the first supply pump ( The primary side pressure PA of 21a) is controlled within the above-mentioned setting range PS. In addition, in the case where the opening degree of the regulating valve 23 is open and close, the primary-side pressure PA of the 1st supply pump 21a is set above by adjustment of the delivery flow volume of the reference|standard dope 52. Control within the range (PS). Thus, since the primary side pressure PA of the 1st supply pump 21a is controlled (pressure control step), in the 1st supply pump 21a, leakage of the cast dope 56 does not generate|occur|produce from a gear etc., and also , cavitation does not occur.

When manufacturing the film 12 of a single layer structure, by the 1st supply pump 21a, the 1st cast dope 75 is supplied to the cast die 28 at a fixed flow rate through the filter 25a ( supply step). The 1st casting|flow_spread dope 75 supplied is continuously discharged from the casting die 28 toward the band 40 which travel|works, and the film 12 is manufactured like 1st Embodiment and 2nd Embodiment do.

When manufacturing the film of a multilayer structure, the valves 87 and 88 for addition shall be opened, and the 1st additive liquid 77 and the 2nd additive liquid 78 are used. In addition, the valve on the upstream side of the first pipe L1 of the valve 73 and the valve on the first branch pipe LB1 side are open, and the valve downstream of the first pipe L1 is closed, and the valve ( 91) to valve 93 become hot air.

By making the valves 87 and 88 for addition into said open/close state, the 1st additive liquid 77 and the 2nd additive liquid 78 are respectively guided to the 1st piping L1. First, the 1st additive liquid 77 guided to the 3rd piping L3 is added to the reference|standard dope 52 guided in the 1st piping L1 from 1st branch position PB1 (1st addition) step). The reference dope 52 and the 1st additive liquid 77 which joined at the 1st connection position PJ1 are mixed by the 1st static mixer 83. At the second branching position PB2, the mixed solution branches into one being guided into the first pipe L1 and one being guided into the fourth branch pipe LB4.

The 2nd additive liquid 78 which has been guided to the 4th pipe|tube L4 is added to the said mixture guided into the 1st pipe|tube L1 (2nd addition step). The mixed solution and the second additive solution 78 joined at the second connection position PJ2 are mixed by the second static mixer 84, and the polymer, the plasticizer, and the UV absorber are mixed in a uniform state. A dope 75 is obtained. 1st flexible dope 75 is guided to 1st piping L1, 2nd branch piping LB2, and 3rd branch piping LB3. To each 1st flexible dope 75 which flows through 2nd branch pipe LB2 and 3rd branch pipe LB3, the said liquid mixture which has been guided into 4th branch pipe LB4 is added, respectively, and the agent mixed uniformly 2 cast|flow_spread dope 76 is obtained. 1st flexible dope 75 which flows through 1st piping L1, 2nd branch piping LB2, 2nd flexible dope 76 which flows through 3rd branch piping LB3, respectively, 1st supply pump 21a ) - by the 3rd supply pump 21c, it is supplied to the casting die 72 through the filters 25a-25c. On the other hand, the reference dope 52 guided to the 2nd piping L2 returns to the tank 17 (returning step).

As described above, in the case of manufacturing the film 12 of a single layer structure and the case of manufacturing the film of the multilayer structure, the valve 87 for addition, the valve 88 for addition, the valve 73, the valve 91 - The valve 93 is switched between opening and closing. Accordingly, the type of the additive solution used and the liquid feeding line are replaced, and the type of the film to be manufactured is replaced.

According to this method, it is not necessary to prepare and store dope for each kind of film to manufacture. Moreover, when replacing the kind of film to manufacture, it is not necessary to change the whole piping of a dope supply apparatus with new dope, and 1st piping downstream from a part of 3rd piping L3 and 1st connection position PJ1 (PJ1) It is enough to replace the inside of L1).

When the primary pressure PA of the first supply pump 21a to the third supply pump 21c detected by the pressure gauge 22 is within the set range PS, the delivery pump 18 and the first supply pump (21a) - The rotation speed of the 3rd supply pump 21c and the opening degree of the regulating valve 23 are maintained, without changing. When the primary side pressure PA of the 1st supply pump 21a - the 3rd supply pump 21c is not within the set range PS, like the 1st and 2nd embodiment, it sends to the controller 24. Thus, the primary pressure PA of the first supply pump 21a to the third supply pump 21c is controlled within the set range PS. That is, when the opening degree of the regulating valve 23 is in an open state instead of being expanded, the return flow rate of the reference dope 52 is adjusted by adjusting the opening degree of the regulating valve 23, and accordingly, the first supply pump ( 21a) to the primary side pressure PA of the third supply pump 21c are controlled within the above-described setting range PS. In addition, in the case where the opening degree of the regulating valve 23 is open and close, it is the primary side of the 1st supply pump 21a - the 3rd supply pump 21c by adjustment of the delivery flow volume of the reference|standard dope 52. The pressure PA is controlled within the set range PS described above. In this way, since the primary side pressure PA of the 1st supply pump 21a - the 3rd supply pump 21c is controlled (pressure control step), it is the 1st supply pump 21a - the 3rd supply pump 21c. In gear, etc., leakage of the 1st flexible dope 75 and the 2nd flexible dope 76 does not generate|occur|produce, and cavitation does not generate|occur|produce either.

For example, as the supply pump 21, a gear pump (manufactured by Shimadzu Corporation) is used, and a film having a three-layer structure is used using the reference dope 52 and the second additive liquid 78 of the following formulation. The case of manufacturing will be described in detail. By setting PALx1.1 to P1 and PAHx0.9 to P2, the setting range PA in this embodiment is set in the range of 0.1 MPa or more and 0.5 MPa or less. Moreover, with respect to the flow volume of the reference|standard dope 52, the addition flow volume in 2nd connection position PJ2 of the 2nd additive liquid 78 is 10 %. The cavitation occurs downstream of the filter 25a of the first pipe L1, downstream of the filter 25b of the second branch pipe LB2, and downstream of the filter 25c of the third branch pipe LB3. It is evaluated by providing an observation window to each, and confirming the presence or absence of the bubble in the 1st casting|flow_spreading dope 75 and the 2nd casting|flow_spreading dope 76 by visually observing from these observation windows. Moreover, the leakage of the 1st casting|flow_spread dope 75 in a gear part, and the 2nd casting|flow_spread dope 76 is also confirmed by visually observing.

The reference dope 52 is the following prescription. The solvent is a mixture consisting of three components, the first component being dichloromethane, the second component methanol, and the third component butanol.

100 parts by mass of TAC

(Acetyl group substitution degree is 2.86, 50 mass parts of recovered chips from the process of film production performed earlier are included)

275 parts by mass of dichloromethane

50 parts by mass of methanol

10 parts by mass of butanol

The 1st additive liquid 77 is the following prescription.

23 parts by mass of plasticizer

63 parts by mass of dichloromethane

12 parts by mass of methanol

2 parts by mass of butanol

The 2nd additive liquid 78 is the following prescription.

22.7 parts by mass of plasticizer

0.3 parts by mass of UV absorber

63 parts by mass of dichloromethane

12 parts by mass of methanol

2 parts by mass of butanol

The above plasticizer is a condensate of ethanediol and adipic acid (number average molecular weight 1000, hydroxyl value 112 mgKOH/g), and the molar ratio of ethanediol/adipic acid in this condensate is 1/ 1 is Said UV absorber is BASF Japan Co., Ltd. product Tinuvin928.

When the primary-side pressure PA of the first supply pump 21a to the third supply pump 21c is controlled by the controller 24 to be (PAL×1.1) or more and (PAH×0.9) or less, In the 1st supply pump 21a - the 3rd supply pump 21c, leakage of the cast dope 56 does not generate|occur|produce in a gear etc., and cavitation does not generate|occur|produce either. On the other hand, when the primary side pressure PA of the 1st supply pump 21a - the 3rd supply pump 21c is less than (PALx1.1) without performing control by the controller 24, the 1st supply pump Cavitation occurs in (21a) to the third feed pump (21c). In addition, when the primary side pressure PA of the 1st supply pump 21a - the 3rd supply pump 21c is larger than (PAH*0.9) without performing control by the controller 24, the 1st supply pump (21a) - The 1st casting|flow_spread dope 75 and the 2nd casting|flow_spread dope 76 leak from the gear part of the 3rd supply pump 21c.

As in the case of the second embodiment, when the mass of the polymer with respect to the mass of the first additive or the second additive is less than the expected range due to adjustment of the return flow rate or adjustment of the delivery flow rate, the valve for addition ( 87, 88) is made smaller than the present. For example, in this embodiment, each addition flow volume of the 1st additive liquid 77 and the 2nd additive liquid 78 is 0.05 times or more of present by making the opening degree of the valve|bulb 87, 88 for addition small. falls within a range less than 1.0. Accordingly, the flow rate ratio of the first additive liquid 77 and the reference dope 52, the second additive liquid 78, and the flow rate ratio of the mixed liquid of the reference dope 52 and the first additive liquid 78 are adjusted. , the mass of the polymer with respect to the mass of the plasticizer and the UV absorber is within the desired range. Thus, also when the flow volume of the 1st additive liquid 77 and the 2nd additive liquid 78 is changed, the flow volume of the 1st casting|flow_spread dope 75 changes. However, also in this example, as in the first and second embodiments, the primary pressure PA of the first supply pump 21a to the third supply pump 21c is detected and controlled within the set range PS. Therefore, in the 1st supply pump 21a - the 3rd supply pump 21c, leakage of the 1st cast dope 75 and the 2nd cast dope 76 does not generate|occur|produce in a gear etc., and cavitation does not generate|occur|produce either. .

Moreover, as mentioned above, the mass ratio of additives, such as a plasticizer and a UV absorber, and a polymer for every film to manufacture is preset. In this embodiment, since the 1st additive liquid 77 and the 2nd additive liquid 78 of the same solid content concentration as the reference dope 52 are used, the additive liquid of the solid content concentration higher than the reference dope 52 is used. Compared with the conventional case, the addition flow rate of the 1st additive liquid 77 with respect to the reference|standard dope 52, and the 2nd additive liquid 78 is made large. Even when the addition flow rate is large in this way, the primary side pressure PA of the first supply pump 21a to the third supply pump 21c is controlled so as not to become large beyond the set range PS, so that the first supply pump ( Leakage of the 1st cast dope 75 and the 2nd cast dope 76 does not generate|occur|produce in the gear etc. of 21a) - the 3rd supply pump 21c.

In addition, in manufacturing by replacing the film 12 of the single layer structure and the film of the multilayer structure, the use of the second additive solution 78 is replaced, and the first additive solution 77 and the second additive solution 78 are also replaced. The addition flow rate with respect to the reference|standard dope 52 of ) differs from each other in many cases. For this reason, by replacement of the film to manufacture, the flow volume of the 1st cast dope 75 to the 1st supply pump 21a, and the 2nd cast dope to the 2nd supply pump 21b and the 3rd supply pump 21c. The flow rate of (76) is changed respectively. However, according to said structure, setting range PS is calculated|required about each of the 1st casting|flow_spread dope 75 and the 2nd casting|flow_spread dope 76, and the 1st supply pump 21a within the setting range PS. ) - Since the primary side pressure PA of the 3rd supply pump 21c is controlled, in the 1st supply pump 21a - the 3rd supply pump 21c, the 1st cast dope 75, the 2nd cast|flow_spread is a gear etc. Leakage of the dope 76 does not generate|occur|produce, and cavitation does not generate|occur|produce either.

In the case of manufacturing a film of a multilayer structure, the first flexible dope 75 is through the filter 25a by the first supply pump 21a, the second flexible dope 76 is the second supply pump 21b, By the 3rd supply pump 21c, it is respectively supplied to the casting die 72 through the filters 25b and 25c at a fixed flow volume (supply step). The 1st casting|flow_spread dope 75 and 2nd casting|flow_spread dope 76 which are supplied are discharged continuously from the casting|flow_spread die 72 toward the band 40 which travel|works. Thereby, the film of the three-layer structure in which the inner layer formed from the 1st flexible dope 75 was pinched|interposed by the outer layer formed from the 2nd flexible dope 76 is manufactured.

In this embodiment, when making a mat agent contain in the film 12 of a single layer structure, in the 1st piping L1 between the 1st supply pump 21a and the filter 25a, a mat agent is a dispersion medium. It is preferable to add a mat agent in the 1st cast|flow_spread dope 75 by supplying the disperse|distributed dispersion liquid. Moreover, when making a mat agent contain in the film of a multilayer structure, 2nd branch piping LB2 between the 2nd supply pump 21b and the filter 25b, and the 3rd supply pump 21c and the filter 25c It is preferable to add a mat agent in the 2nd cast|flow_spread dope 76 by respectively supplying the dispersion liquid which disperse|distributed the mat agent to the dispersion medium to at least any one of 3rd branch piping LB3 between.

The film 12 of the single-layer structure obtained by 1st - 3rd embodiment, and the film of the 3-layer structure obtained by 3rd embodiment can be used as an optical film, when a transparent thing is used as a polymer. As an optical film, the protective film of a polarizing plate, and retardation film are mentioned, for example.

Examples of the transparent polymer include cellulose acylate and cyclic polyolefin, which can be used in each of the above embodiments. About cellulose acylate, the detail is demonstrated below.

<Cellulose acylate>

In cellulose acylate, the ratio of esterifying the hydroxyl group of cellulose with carboxylic acid, that is, the degree of substitution of the acyl group (hereinafter referred to as the degree of substitution of the acyl group) satisfies all the conditions of the following formulas (1) to (3) Especially preferred. Moreover, in (1)-(3), both A and B are acyl group substitution degrees, the acyl group in A is an acetyl group, and the acyl group in B is a C3-C22 thing.

2.4≤A+B≤3.0... (One)

0≤A≤3.0... (2)

0≤B≤2.9... (3)

The glucose unit constituting cellulose and bonded to β-1,4 has a free hydroxyl group at the 2nd, 3rd and 6th positions. Cellulose acylate is a polymer in which a part or all of the hydroxyl groups of such cellulose are esterified, and hydrogen of the hydroxyl group is substituted with an acyl group having 2 or more carbon atoms. In addition, if the esterification of one hydroxyl group in the glucose unit is 100%, the degree of substitution is 1, so in the case of cellulose acylate, if the hydroxyl groups at the 2nd, 3rd and 6th positions are each 100% esterified, the degree of substitution is becomes 3

Here, in the glucose unit, the total (DS2+DS3+DS6) obtained by setting the degree of substitution of the acyl group at the 2nd position as DS2, the degree of substitution of the acyl group at the 3rd position as DS3 and the degree of substitution of the acyl group at the 6th position as DS6 as “DS2+DS3+DS6” ) It is preferable that acyl group substitution degree is 2.00-3.00, It is more preferable that it is 2.22-2.90, It is more preferable that it is 2.40-2.88. Moreover, it is preferable that it is 0.32 or more, as for "DS6/(DS2+DS3+DS6)", it is more preferable that it is 0.322 or more, It is more preferable that it is 0.324-0.340.

One type may be sufficient as an acyl group, and two or more types may be sufficient as it. When there are two or more types of acyl groups, it is preferable that one is an acetyl group. Let DSA be the sum of the degrees of substitution by acetyl groups of hydrogen in the hydroxyl groups at 2-positions, 3-positions and 6-positions, and the sum of the degrees of substitution by acyl groups other than the acetyl groups in 2-positions, 3-positions and 6-positions is defined as DSB. It is preferable that it is 2.2-2.86, and, as for the value of "DSA+DSB", it is especially preferable that it is 2.40-2.80. It is preferable that DSB is 1.50 or more, and it is especially preferable that it is 1.7 or more. And, as for DSB, although it is preferable that 28% or more are substitution of 6-position hydroxyl group, More preferably, 30% or more, More preferably, 31% or more, Especially preferably, 32% or more is substitution of a 6-position hydroxyl group. it is preferable Moreover, it is preferable that the value of "DSA+DSB" of 6th-position of a cellulose acylate is 0.75 or more, It is more preferable that it is 0.80 or more, It is especially preferable that it is 0.85 or more. By using the above cellulose acylates, in order to make the polymer solution used for solution film forming, preferable solubility is acquired.

As an acyl group having 2 or more carbon atoms, an aliphatic group or an aryl group may be sufficient, and it is not specifically limited. For example, there are alkylcarbonyl esters, alkenylcarbonyl esters or aromatic carbonyl esters and aromatic alkylcarbonyl esters of cellulose, and these may each have a further substituted group. propionyl group, butanoyl group, pentanoyl group, hexanoyl group, octanoyl group, decanoyl group, dodecanoyl group, tridecanoyl group, tetradecanoyl group, hexadecanoyl group, octadecanoyl group, iso-butanoyl group, t -butanoyl group, cyclohexanecarbonyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group, etc. are mentioned. Among these, propionyl group, butanoyl group, dodecanoyl group, octadecanoyl group, t-butanoyl group, oleoyl group, benzoyl group, naphthylcarbonyl group, cinnamoyl group, etc. are more preferable, propionyl group, butanoyl group is particularly preferred.

When using a cellulose acylate as a polymer, as each solvent of the dope 11, the flexible dope 56, the 1st flexible dope 75, and the 2nd flexible dope 76, a cellulose acylate film is solution film-forming. A well-known thing can be used as a solvent of dope in the case of manufacturing. For example, dichloromethane, various alcohols, various ketones, and the like. You may use the mixture which mixed the plurality chosen from these as a solvent. When using a mixture as a solvent, it is good also as a mixture which added the poor solvent to the good solvent of cellulose acylate. It is preferable that each solvent of the additive liquid 53 in the case of using cellulose acylate as a polymer, the 1st additive liquid 77, and the 2nd additive liquid 78 has a component common to the solvent of a cellulose acylate. .

Although each said embodiment is an example which used the casting die as a discharge part, a discharge part is not limited to this.

10 Solution film forming equipment
11 dope
12 film
13 dope feeder
14 Film making equipment
17 tank
18 delivery pump
21 feed pump
22 pressure gauge
23 regulating valve
24 controller
28, 72 flexible die
52 reference dope
56 flexible dope
58, 77, 78 addition valve
L1 to L3 1st to 3rd piping
75, 76 1st, 2nd flexible dope

Claims (17)

The polymer solution stored in the storage unit and the polymer dissolved in the solvent is guided to the casting die by the first pipe extending from the storage unit to the casting die, and continuously from the casting die. In the solution film forming method of manufacturing a film by discharging and drying,
a sending step of sending out the polymer solution stored in the reservoir by a sending pump;
A supply process of supplying the polymer solution sent from the storage part to the casting die at a constant flow rate by a supply pump which is a gear pump provided downstream of the delivery pump;
An additive solution in which the additive contained in the film is dissolved in a solvent is added to the polymer solution in the first pipe through a third pipe connecting between the delivery pump of the first pipe and the supply pump process and
a pressure detection step of detecting the pressure on the primary side of the supply pump;
A casting process of continuously discharging the polymer solution from the casting die onto a flexible support to form a flexible film;
A peeling step of peeling the cast film from the cast support;
a drying step of drying the film formed by peeling in the peeling step;
A part of the polymer solution from the delivery pump is returned to the reservoir by a second pipe that branches from a connection position where the delivery pump of the first pipe and the third pipe are connected and is connected to the reservoir. ,
A solution film forming method characterized in that the primary side pressure is controlled within a predetermined range by adjusting an opening degree of a regulating valve provided in the second pipe based on a detection result in the pressure detecting step. According to claim 1,
The solution film forming method which adjusts the flow volume of the said additive liquid by the valve for addition provided in the said 3rd piping. 3. The method of claim 1 or 2,
The said additive liquid and the said polymer solution have the same concentration of solid content, the solution film forming method. 3. The method of claim 1 or 2,
When the type of the film to be manufactured is replaced, the type of the additive solution is replaced. delete delete delete delete delete delete delete delete delete delete delete delete delete

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