JP6735641B2 - Film manufacturing apparatus and film manufacturing method - Google Patents

Description

The present invention relates to a film manufacturing apparatus and a film manufacturing method. More specifically, the present invention relates to a film production apparatus for producing a resin film by carrying out a melt extrusion method. The present invention also relates to a film manufacturing method for manufacturing a resin film by a melt extrusion method.

A T-die method by melt extrusion is known as a method for producing a high-quality thermoplastic resin film for optical applications and the like. This method is generally called a melt extrusion method.
The film manufacturing apparatus for carrying out the melt extrusion method is composed of a device and equipment on the extruder side and a group of rolls downstream thereof.
The rolls can be divided into casting rolls that contribute to forming and guide rolls that cool and guide the sheet when they are classified by use and function.

In the film formation by the melt extrusion method, the resin extruded from the T die of the extruder is in contact with a plurality of rolls before being wound by the winding device.
Therefore, if foreign matter adheres to the roll, defects will occur in the sheet. Further, defects caused by rolls occur periodically, so that defective portions may extend to the entire length of the film and the entire lot may become defective.

Patent Document 1 discloses a means for solving this problem.
The invention disclosed in Patent Document 1 has a problem of a film defect caused by a guide roll.
The invention disclosed in Patent Document 1 is a sheet periodic defect detection apparatus, which detects a defective portion of a sheet by irradiating the sheet with light. Further, in Patent Document 1, the guide roll that causes the periodic defect is specified from the defect occurrence period and the circumferential length of the guide roll.
Further, the apparatus disclosed in Patent Document 1 includes a roll cleaning unit that cleans a guide roll that causes a periodic defect.
The roll cleaning means disclosed in Patent Document 1 is “a device that presses a soft non-woven fabric against a guide roll, or an ultrasonic removing device”.
The roll cleaning means disclosed in Patent Document 1 does not move in the width direction of the roll. Further, the roll cleaning means disclosed in Patent Document 1 does not contain water.

JP, 2014-167391, A

In the melt extrusion method, the resin extruded from the T die of the extruder first contacts the cast roll. The surface roughness of the film is determined by the cast roll.
Therefore, the cast roll is cleaned before the film is manufactured.
However, for some reason, the protein may adhere to the surface of the cast roll.
When the protein is attached to the cast roll, the film formed in contact with the cast roll becomes defective. The protein adhering to the cast roll is transferred to the film each time the cast roll makes one revolution, and appears as a periodic dent defect in the film.
For example, when a periodic defect is found by the inspection device, the cast roll is cleaned, but cleaning the cast roll is often performed manually, which is troublesome and requires a considerable work time. It costs. In addition, when the cleaning work is manually performed, the cast roll may be touched by the hand, and the protein may be newly attached.

Further, the present inventors, in order to control the thickness and surface properties of the film more accurately, the touch roll is opposed to the cast roll to form a pair of roll pairs, and a molten resin is sandwiched between the roll pairs. Forming film.
In this way, in the case of an apparatus structure in which a molten resin is sandwiched between a pair of rolls to form a film, a dent defect occurs periodically in the film, and even if this is found, the roll that caused the problem It is not possible to easily determine whether it is a cast roll or a touch roll.

Therefore, both the cast roll and the touch roll are cleaned, but the cleaning work is troublesome. Further, as described above, there is a concern that a protein may be newly attached during cleaning.
In particular, when one roll pair is composed of the cast roll and the touch roll, when cleaning one roll, the other roll is touched. Therefore, the roll on the clean side may be soiled.

The present invention focuses on the above-mentioned problems of the prior art, and proposes a measure for removing foreign matters on the roll surface, targeting a roll pair that sandwiches the resin extruded from the extruder and contributes to the molding.

Aspects for solving the above problems, an extruder, and at least one set of roll pairs, in the film manufacturing apparatus for forming a film by sandwiching the resin extruded from the extruder between the roll pairs At least two rolls forming the roll pair have different peripheral lengths, and a film inspection machine that detects a defect generated in the film on the downstream side of the roll pair and cleans the rolls forming the roll pair. A roll cleaning unit is provided, and a roll function that identifies the roll on the side causing the defect from the roll pair based on the cycle in which the defect appears and cleans the identified roll by the roll cleaning unit is provided. The film manufacturing apparatus is characterized in that

The roll cleaning means has a cleaner head that presses a cleaning member against the roll, and the cleaner head is shorter than the effective width of the roll to be cleaned and moves the cleaner head in the width direction of the roll to be cleaned. With the head moving means, the film inspection machine can specify the position of the defective film in the width direction, and the cleaner head moves to the position in the width direction of the roll corresponding to the position specified by the film inspection machine. It is desirable to clean the specified roll by pressing a cleaning member against the relevant part of the roll.

In each of the above-mentioned aspects, it is desirable that the roll cleaning means contains water and can effectively remove the protein attached to the roll.

In each of the above-described aspects, it is desirable that the roll pair is a roll pair in which the molten resin extruded from the die mounted on the extruder first contacts.

Using one of the above-mentioned film manufacturing apparatuses, during the preparatory stage of film manufacturing and/or during film manufacturing, a resin in a molten state extruded from an extruder is sandwiched between the roll pairs to form a film-shaped resin, It is desirable to detect a defect by inspecting the resin in a film inspection machine, identify the roll on the side that caused the defect based on the cycle in which the defect appears, and clean the identified roll with a roll cleaning means. ..

An aspect relating to a method for producing a film is a film producing method of forming a film by sandwiching a resin in a molten state extruded from an extruder with a pair of roll pairs, and at least two rolls constituting the roll pair. The peripheral length is different, a film inspection machine for detecting a defect occurring in the film on the downstream side of the roll pair is arranged, and a roll cleaning means for cleaning the rolls forming the roll pair is provided, and a preparatory step for film production and During the film production, the resin in a molten state extruded from the extruder is sandwiched by the roll pair to form a film-shaped resin, and the film-shaped resin is inspected by a film inspection machine to detect a defect, and a defect appears. The film manufacturing method is characterized in that the roll on the side causing the defect is specified from the roll pair based on the cycle, and the specified roll is cleaned by a roll cleaning means.

The roll cleaning means has a cleaner head that presses a cleaning member against the roll, and the cleaner head is shorter than the effective width of the roll that is the cleaning target, and moves the cleaner head in the width direction of the roll that is the cleaning target. Means, the film inspecting machine is capable of specifying the position of the defective film in the width direction, and the head moving means cleans the position in the width direction of the roll corresponding to the position specified by the film inspecting machine. It is desirable to move the head and press the cleaning member against the corresponding part of the roll to clean the roll.

In each of the above-described film manufacturing methods, it is desirable that the roll cleaning means contains water and can effectively remove the protein attached to the roll.

In each of the above-described film manufacturing methods, during or after cleaning the roll with a cleaning member, detection of defects occurring in the film is continued or restarted, the defect occurrence period and width direction position before the cleaning, and the cleaning. It is desirable to compare the subsequent defect occurrence period and the width direction position.

When a film is manufactured using the film manufacturing apparatus of the present invention, a film with few defects can be manufactured. Moreover, when a film is manufactured based on the film manufacturing method of the present invention, a film with few defects can be manufactured.

It is a conceptual diagram of the film manufacturing apparatus of embodiment of this invention. It is a perspective view of the cast roll vicinity of the film manufacturing apparatus of FIG. 1, and is a perspective view of a cast roll and a cleaning means. It is a block diagram of a cast roll and a cleaning means. (A) thru|or (d) are explanatory drawings which show operation|movement of the cleaning means of the film manufacturing apparatus of FIG. It is explanatory drawing which shows the film discharged from the roll pair. 3 is a flowchart showing the operation of the film manufacturing apparatus of FIG.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 shows a layout of a film manufacturing apparatus 1 according to an embodiment of the present invention. First, the outline of the film manufacturing apparatus 1 will be described.
The film manufacturing apparatus 1 has an extruder 2 for extruding a molten resin, and a T die 3 is attached to the tip of the extruder 2.
In the film manufacturing apparatus 1, the roll pair 8 is located immediately after the extruder 2. The roll pair 8 is formed by sandwiching a molten resin into a sheet shape, one of which is the cast roll 5 and the other of which is the touch roll 6.
The cast roll 5 and the touch roll 6 are arranged to face each other with a slight gap. Both the cast roll 5 and the touch roll 6 are temperature-controlled.

A roll group 10 is provided on the downstream side of the roll pair 8.
In FIG. 1, the roll group 10 includes seven rolls 11a to 11g, but the number of rolls is arbitrary. In this embodiment, the rolls 11a to 11c are cooling rolls. The rolls 11d and below are guide rolls.
Further, a winding device 12 is provided further downstream of the roll group 10.

In the present embodiment, a film inspection machine 15 is provided on the downstream side of the roll pair 8 and the cooling rolls 11 a to 11 c and before reaching the winding device 12.

In the film manufacturing apparatus 1, the resin melted and kneaded in the extruder 2 is extruded in a sheet form from the T die 3 and first introduced between the roll pair 8 composed of the cast roll 5 and the touch roll 6. It
The introduced resin is sandwiched between the cast roll 5 and the touch roll 6 to adjust the thickness and surface roughness.
Then, the film is cooled by the roll group 10 on the downstream side, is inspected by the film inspection machine 15 for the presence or absence of defects, and is then wound up by the winding device 12.

Next, a configuration unique to the film manufacturing apparatus 1 of this embodiment will be described.
As described above, in the film manufacturing apparatus 1, the roll pair 8 is located immediately after the extruder 2, and the roll pair 8 is sandwiched between the roll pairs 8 to define the thickness of the film 16 and the like.
In the roll pair 8 used in this embodiment, the cast roll 5 and the touch roll 6 have different outer diameters and different perimeters.
The difference between their outer peripheries is 1 mm or more. The difference between them is preferably 2 mm or more, more preferably 4 mm or more. The most recommended difference is 20 mm or more.
The difference between the outer peripheries of the two is preferably larger, but should not exceed the film length that can be stored by the film inspection machine 15.

That is, as will be described later, since the film inspecting machine 15 detects the cycle in which the same defect occurs, it is necessary to store the position of the detected defect and the like. Since there is a limit to the amount that the film inspecting machine 15 can store, the difference in circumferential length between the cast roll 5 and the touch roll 6 must not exceed this.
Considering the length that can be stored in the film inspection machine 15, the difference between the circumferential lengths of the cast roll 5 and the touch roll 6 is preferably 1600 mm or less, and more preferably 1300 mm or less. More preferably, the thickness is 1000 mm or less.
In reality, the difference in circumferential length between the cast roll 5 and the touch roll 6 is preferably 300 mm or less.

A combination in which the difference between the circumferences of the cast roll 5 and the touch roll 6 is an integral multiple of the circumference of the smaller roll should be avoided.

Therefore, the difference in peripheral length between the cast roll 5 and the touch roll 6 is preferably 1 mm or more and 1600 mm or less, more preferably 2 mm or more and 1300 mm or less, and further preferably 4 mm or more and 1000 mm or less.
Most recommended is 20 mm or more and 300 mm or less.
Any of the circumferences of the cast roll 5 and the touch roll 6 may be long.
In this embodiment, the circumference of the touch roll 6 is longer than the circumference of the cast roll 5.

Roll cleaning means 20 and 21 are arranged near the cast roll 5 and the touch roll 6, respectively.
Since the two roll cleaning means 20 and 21 have the same mechanism, the roll cleaning means 20 on the cast roll 5 side will be described as a representative.
The roll cleaning means 20 has a cleaner head 28 as shown in FIGS. 2 and 3, and a cleaning cloth 22 containing water is pressed against the surface of the cast roll 5 by the cleaner head 28 and adhered to the surface of the cast roll 5. It removes proteins.
Further, the roll cleaning means 20 has a traveling function of moving the cleaner head 28 in the width direction of the cast roll 5, and presses the cleaning cloth 22 mainly on the portion where the protein is attached.

That is, the roll cleaning means 20 includes a cleaner head 28 having a cleaning cloth 22, a head pressing mechanism 23 that moves the pressing pad 31 of the cleaner head 28 to the cast roll 5 side and presses it against the surface of the cast roll 5. It has a head traveling mechanism 25 for moving the cleaner head 28 in the width direction of the cast roll 5.
The roll cleaning means 20 also includes a water supply device 27.
Further, the roll cleaning means 20 has a blade 50 that physically cleans the surfaces of the rolls 5 and 6, and a blowing nozzle 51 that dries the rolls 5 and 6.

The cleaner head 28 has a feeding roll 30, a pressing pad 31, and a winding roll 32 as shown in FIGS. 2, 3, and 4.
The pay-out roll 30 is a roll that idles. However, the feeding roll 30 is provided with a brake mechanism, and a certain amount of torque is required to rotate the feeding roll 30.
The take-up roll 32 is intermittently rotated by a motor (not shown).

The pressing pad 31 has a pressing portion 43 on the front side. The pressing portion 43 has a curved surface.
A main water supply pipe 45 is inserted in the pressing pad 31 in the width direction. Further, the pressing pad 31 is provided with a plurality of through holes 46 penetrating from the main water supply pipe 45 to the pressing portion 43 side.
A tube 47 is connected to the end of the main water supply pipe 45 and is connected to the water supply device 27. The water supply device 27 includes a water supply tank 53 and a pump 55.

The width of the above-mentioned cleaner head 28 is much shorter than the width of the cast roll 5. That is, the width of the pressing pad 31 is much shorter than the width of the cast roll 5.

The arrangement of the feeding roll 30, the pressing pad 31, and the winding roll 32 is as shown in FIGS. 2, 3, and 4, and the pressing pad 31 is on the cast roll 5 side, and the feeding roll 30 and the winding roll 32 are arranged. Is behind the pressing pad 31. That is, the pay-out roll 30, the pressing pad 31, and the winding roll 32 are arranged in positions that form a triangle, and the pressing pad 31 forms the projecting end portion thereof.

Then, the cleaning cloth 22 is wound around the three parts of the feeding roll 30, the pressing pad 31, and the winding roll 32.
That is, the roll of the cleaning cloth 22 before use is mounted on the payout roll 30. Then, the cleaning cloth 22 is wound around the pressing pad 31 that constitutes the protruding end and is wound around the winding roll 32.

The head pressing mechanism 23 moves the pressing pad 31 back and forth to the cast roll 5 side by using a motor, a solenoid, an air cylinder, a hydraulic cylinder, and the like.
In the present embodiment, the air cylinder 56 is used for the head pressing mechanism 23.
The air cylinder 56 of the head pressing mechanism 23 is arranged on the back side of the pressing pad 31. By extending the rod of the air cylinder 56, the pressing pad 31, which is a part of the cleaner head 28, can be pressed against the cast roll 5. Further, by contracting the rod of the air cylinder 56, the contact pad 31 of the cleaner head 28 leaves the cast roll 5.

The head traveling mechanism 25 linearly moves the cleaner head 28 in the width direction of the cast roll 5 by using a screw mechanism, a rack and pinion, a belt, or the like.
In this embodiment, the cleaner head 28 is fixed to the carrier 58 that has the guide rail 57 and engages with the guide rail 57.
The carrier 58 travels on the guide rail 57 by a motor (driving source) not shown, and linearly moves the cleaner head 28 in the width direction of the cast roll 5.

A motor (not shown) that drives the head traveling mechanism 25 is a stepping motor, and the traveling amount of the carrier 58 can be controlled by integrating the number of rotations. Therefore, the head traveling mechanism 25 can stop the cleaner head 28 at a desired position.
The cleaner head 28 can stand by at the standby position, travel along the cast roll 5 by the head traveling mechanism 25, move in the width direction of the cast roll 5, and stop at a predetermined position.

Next, the film inspection machine 15 will be described.
The film inspection machine 15 is a defect inspection machine that detects fine defects in the film 16 by optical means. Specifically, light is transmitted through the film 16, and a defect is detected by the shadow or the like. For example, the film inspecting machine 15 is capable of grasping the brightness of the transmitted light, and detects a portion having a different brightness as a defective portion as compared with the brightness of the light passing through the whole (texture). Depending on the cross-sectional shape of the defect, it may appear darker or brighter than the texture.
The brightness of the transmitted light is an index indicating the degree of the defect. That is, there are two types of defects, one in which the protein is heavily transferred and the other in which the protein is thinly transferred, and the density of the defect can be detected by the brightness of the transmitted light.

Further, the film inspection machine 15 can grasp the position, size, etc. of the defect. The film inspection machine 15 may be capable of grasping the shape.
The position of the defect is a position in the width W direction of the film 16 as shown in FIG. 5, and is specified as a position of a distance A from the end in the width direction toward the center. Further, a method in which the address of one end of the film 16 in the W direction is set to 0 and the position in the width direction is specified by the distance from the end may be considered.
Further, the film inspecting machine 15 can detect the defect occurrence cycle.
For example, as shown in FIG. 5, when a part of the cast roll 5 has protein stains 40, the stains 40 adhere to the film 16 at regular intervals as the cast roll 5 rotates, and the defects 41 appear at regular intervals. Occurs.
The film inspection machine 15 can detect the generation cycle B of the defect 41.

The film manufacturing apparatus 1 of the present embodiment has a control device 42 as shown in FIG. 1, and a signal from the film inspection machine 15 is input to the control device 42. Further, the controller 42 controls the roll cleaning means 20.
The control device 42 has a known CPU and storage means, and stores an inspection data calculation program, a roll identification program, and a cleaning means control program as shown in FIG.

The inspection data calculation program can be detected by the film inspection machine 15 and analyze the data to grasp the position, size, density and the like of the defect 41 and store it temporarily.
The presence or absence of the defect 41 caused by the same stain 40 is detected from the stored position, size and shape of the defect 41. Further, when there is a defect 41 caused by the same stain 40, the generation period thereof is calculated.

The roll identification program identifies the roll to which the stain 40 is attached based on the cycle of occurrence of the defect 41 and the circumferential lengths of the cast roll 5 and the touch roll 6.
That is, the defect 41 is caused by the cast roll 5 or the touch roll 6, and the stain 40 of one of the rolls 5 and 6 is transferred to the film 16. Since the stain 40 adheres to the film 16 every time the cast roll 5 or the touch roll 6 makes one revolution, the defects 41 appear on the film 16 at intervals of an integral multiple of the circumferential length of the causal roll.
On the other hand, in the present embodiment, since the circumferences of the cast roll 5 and the touch roll 6 are different, the cycle of the defect 41 changes depending on which of the cause rolls. On the contrary, by knowing the cycle of the defect 41, it can be determined whether the cause roll is the cast roll 5 or the touch roll 6.

Then, according to the cleaning means control program of the control device 42, the roll cleaning means 20 and 21 in charge of the cause roll are driven. For example, if the roll causing the defect 41 is the cast roll 5, the cleaning means 20 arranged near the cast roll 5 is driven. If the roll causing the defect 41 is the touch roll 6, the cleaning means 21 arranged near the touch roll 6 is driven.
That is, the head traveling mechanism 25 on the cause rolls 5, 6 side is driven to move the cleaner head 28 in the width direction of the target roll, and stop the cleaner head 28 at a position corresponding to the defect 41 of the film 16 (FIG. 4). (A)).

Subsequently, as shown in FIG. 4B, the cleaner head 28 is advanced to the cause rolls 5, 6 side, and the cleaning cloth 22 of the pressing pad 31 is pressed against the cause rolls 5, 6. Since the cause rolls 5 and 6 continue to rotate, the dirt 40 is wiped off by the cleaning cloth 22 as shown in FIG.

Further, the cleaner head 28 employed in the present embodiment has a water supply main pipe 45 built in the pressing pad 31, and water is supplied from the water supply device 27 to the water supply main pipe 45. Then, the water leaks from the main water supply pipe 45 to the pressing portion 43 side through the through hole 46 penetrating to the pressing portion 43 side, and the cleaning cloth 22 is made to contain the water.
Therefore, the causal rolls 5 and 6 are wiped with the cleaning cloth 22 containing water.
Further, dry air is supplied from the blower nozzle 51, and the water attached to the causal rolls 5 and 6 evaporates.

Then, as shown in FIG. 4C, the pressing pad 31 is returned and the cleaning cloth 22 is separated from the causal rolls 5 and 6. Then, as shown in FIG. 4D, the take-up roll 32 is rotated to take up the cleaning cloth 22 having the dirt 40 attached thereto, and move the new surface of the cleaning cloth 22 to the position of the pressing pad 31.

Further, the head traveling mechanism 25 is driven to return the cleaner head 28 to the standby position.
Then, it waits for a certain time in this state. When the defect 41 does not occur at the relevant portion of the film 16, the cleaner head 28 of the roll cleaning means 20 is stopped at the standby position.
When the defect 41 continues to occur, the head traveling mechanism 25 is driven again to move the cleaner head 28 in the width direction of the target roll, and the cleaner head 28 is stopped at a position corresponding to the defect 41 of the film 16. (FIG. 4(a)).

Then, as shown in FIG. 4B, the cleaner head 28 is moved forward again toward the causal rolls 5 and 6, and the pressing pad 31 presses the cleaning cloth 22 against the causal rolls 5 and 6 for a certain period of time to wipe off the dirt 40.
This operation is repeated a fixed number of times.
Note that the cleaner head 28 may be returned to the standby position if the defect 41 does not occur at the relevant portion of the film 16 without waiting the cleaner head 28 to return to the standby position for a certain time.

Next, a series of operations of the film manufacturing apparatus 1 of the present embodiment will be described based on the flowchart of FIG.
The following operations are preferably performed in the setup stage before the full-scale production of the film 16, but may be performed during the production of the film 16.
As a preparatory step, the raw material resin is put into the extruder 2 and the resin is melted and kneaded in the extruder 2. Then, the molten resin is extruded in a sheet form from the T-die 3, sandwiched between a roll pair 8 composed of a cast roll 5 and a touch roll 6 to adjust the thickness and the like, cooled by a roll group 10, and a film inspection It is wound on the winding device 12 via the machine 15.

Then, the film inspection machine 15 continuously monitors in-line whether or not the film 16 has a defect. When the defect 41 of the film 16 is found in step 1, after step 2, it is determined whether the occurrence of the defect 41 is periodic. Specifically, it is determined whether or not defects of the same size are continuously generated at the same position in the width direction of the film 16 with a constant interval.
If there is no periodicity, it is expected that it is a defect due to sudden dirt or dust, so the procedure returns to step 1.
When the defect 41 occurs with periodicity, it is supposed that the stain 40 attached to the cast roll 5 or the touch roll 6 is the cause.

In this case, the process proceeds to step 3 and the generation cycle of the defect 41 is measured. Then, in steps 4, 5, 6, and 7, it is determined whether the causal roll is the cast roll 5 or the touch roll 6.
That is, the process proceeds to step 4, and if the generation cycle of the defect 41 is the same as the circumference of the cast roll 5 or if the generation cycle of the defect 41 is an integral multiple of the circumference of the cast roll 5, 5, the cause roll is determined to be the cast roll (abbreviated as C roll in the drawing) 5.

If the generation cycle of the defects 41 is not the same as the circumference of the cast roll 5 and is not an integral multiple, the process proceeds to step 6 and the generation cycle is the same as the circumference of the touch roll 6 or the touch roll 6 It is determined whether or not it is an integral multiple of the perimeter of.
When the generation cycle is the same as the circumference of the touch roll 6 or is an integral multiple of the circumference of the touch roll 6, the process proceeds to step 7, and the cause roll is the touch roll (abbreviated as T roll in the drawing) 6 Is determined.

When the generation cycle of the defect 41 does not match the circumference of the cast roll 5 or the circumference of the touch roll 6, the process returns to step 1.

When the cause roll is identified in steps 4, 5, 6, and 7, the roll cleaning means 20 and 21 corresponding to the identified rolls 5 and 6 operate in the following steps.

When the cause roll is identified in steps 4, 5, 6 and 7, the process proceeds to step 8 and the width of the rolls 5 and 6 corresponding to the position where the dirt 40 is attached is determined from the data of the film inspection machine 15. The cleaner head 28 moves to the position in the direction. For example, as shown in FIG. 5, if the position of the defect 41 is at the position of the distance A from the end to the center, the cleaner head 28 moves along the rolls 5 and 6 and moves in front of the position of the dirt 40. Stop at.

Then, the process proceeds to step 10 and 1 is added to the counter.
Next, in step 11, the cleaner head 28 is moved forward as shown in FIG. 4B to press the cleaning cloth 22 containing water against the rotating rolls 5 and 6 to clean the rolls 5 and 6. ..
In steps 12 and 13, the time is counted, and the cleaner head 28 maintains the inclined posture for a certain period of time, and the cleaning cloth 22 containing water is continuously pressed against the rotating rolls 5 and 6. Then, when a certain time has elapsed in step 13, the process moves to step 14 and the cleaner head 28 is returned to the standby position.
Then, the process proceeds to step 15, waits for a certain period of time, and checks whether the same defect occurs.
When the occurrence of defects is stopped, the process proceeds to step 16 to clear the counter and the process returns to step 1.

If the same defect 41 continues to occur, the process proceeds to step 17 and the number of counters is confirmed. If the numerical value of the counter is not equal to or more than a certain value such as 3, the process returns to step 10, 1 is added to the counter, and the cleaning of the rolls 5 and 6 by the cleaning cloth 22 is repeated. That is, the cleaner head 28 is moved forward to press the cleaning cloth 22 containing water against the rotating rolls 5 and 6, and the cleaning cloth 22 containing water is pressed against the rotating rolls 5 and 6 for a predetermined time. Keep hitting.
When the occurrence of the defect 41 is stopped, the process proceeds to step 16, the counter is cleared, and the process returns to step 1.

If the defect 41 continues to occur, the process proceeds to step 17 and the number of counters is confirmed. That is, the number of times the cleaning process is performed is confirmed. Then, the cleaning process is repeated a prescribed number of times, and if the counter number has reached a certain value, the process proceeds to step 18 and a notification means (not shown) notifies that the stain cannot be removed.
That is, if the generation of the defect 41 does not stop even after the cleaning by the cleaner head 28 is repeated a certain number of times (three times in the embodiment), the notification means (not shown) notifies that the stain cannot be removed.
In that case, the operator manually cleans the rolls 5 and 6.

In the film manufacturing apparatus 1 of the present embodiment, when the defect 41 of the film 16 occurs, the rolls 5 and 6 that are the causes are automatically identified, and the rolls 5 and 6 are automatically cleaned to remove the dirt 40. can do.
Further, in the film manufacturing apparatus 1 of the present embodiment, since the cleaning cloth 22 of the roll cleaning means 20 and 21 contains water, the protein stain 40 can be effectively removed.

In the embodiment described above, as a measure for moistening the cleaning cloth 22, a water supply pipe is provided in the cleaner head 28 and water is supplied to the cleaning cloth 22, but all the water supply pipes are provided outside the cleaner head 28. It may be provided.
For example, the water supply nozzle may be fixed at the standby position of the cleaner head 28, and water may be dropped from the water supply nozzle onto the cleaning cloth 22 when the cleaner head 28 is at the standby position.

Next, an experiment conducted to confirm the effect of the present invention will be described.
As an example of the present invention, by using the film manufacturing apparatus 1 shown in FIG. 1, the acrylic thermoplastic resin is melted and the resin is extruded from the T die 3 into a sheet shape, and is composed of a cast roll 5 and a touch roll 6. The resin film 16 of “film length 1000 m/roll 1” was formed while being sandwiched between the roll pair 8 that is formed.
In the film manufacturing apparatus 1 used, the diameter of the touch roll 6 was larger than the diameter of the cast roll 5, and the difference in the outer peripheral length between the two was 30 mm.
The film inspection machine 15 was installed on the downstream side of the process. As the film inspection machine 15, a defect inspection machine of a transmission optical system including a line sensor camera and LED illumination was used.
Then, the film inspecting machine 15 detected the defects in the film 16 in-line, and determined the defects having the periodicity at equal intervals in the running direction as the periodic defects.
Further, wet roll cleaners having a head width of 100 mm are arranged as roll cleaning means 20 and 21 near the surfaces of the cast roll 5 and the touch roll 6, respectively, and automatically based on the information of the periodic defects detected by the film inspection machine 15. The target rolls 5 and 6 are moved to the defect occurrence position and cleaned.

The film production is started by using the film production apparatus 1 of this configuration, and as a result of automatically removing the causative foreign matter by the roll cleaner (roll cleaning means 20, 21) for the periodic defects detected in-line, the film production is started. The periodic defects, which were present at 4 points in total width, were completely removed after the film was formed for 100 m, and thereafter, even if the film was wound and rewound three times, no new periodic defects were generated.
[Comparative Example 1]

The resin film 16 was molded with the same configuration as that of the example except that the outer circumferences of the cast roll 5 and the touch roll 6 were the same.
In the film manufacturing apparatus of the comparative example, when a periodic defect is generated, both the cast roll 5 and the touch roll 6 are sequentially cleaned.
As a result, at the start of film formation, three periodic defects were generated in the entire width, and the rolls 5 and 6 on which the causative foreign matter was not adhered were cleaned first. A film was formed, and the loss length was expanded as compared with the examples. After the cleaning process, no new periodic defects were generated.
[Comparative Example 2]

The resin film 16 was molded with the same configuration as that of the example except that the roll cleaner (roll cleaning means 20, 21) was not provided, and the cleaning was carried out manually.
As a result, three periodic defects were generated in the entire width at the start of film formation, and a film of about 900 m was formed by the completion of cleaning, and the loss length was greatly expanded as compared with Example and Comparative Example 1. In addition, a new periodic defect, which is thought to be caused by another foreign substance adhering to the roll surface during the cleaning work, has occurred after cleaning, and the cleaning work will be performed again, resulting in a further increase in the loss length. Became.

1 Film Manufacturing Equipment 2 Extruder 3 T Die 5 Cast Roll 6 Touch Roll 8 Roll Pair 15 Film Inspector 16 Film 20, 21 Roll Cleaning Means 22 Cleaning Cloth 25 Head Travel Mechanism (Head Moving Means)
28 Cleaner head 31 Pressing pad 40 Dirt 41 Defect

Claims (9)

Extruder, having at least one set of roll pairs, in the film manufacturing apparatus for forming a film by sandwiching the resin extruded from the extruder between the roll pairs,
At least two rolls constituting the roll pair have different circumferences,
A film inspecting device for detecting a defect generated in the film on the downstream side of the roll pair, and a roll cleaning means for cleaning the rolls forming the roll pair,
It is characterized by having a cleaning function of identifying the roll on the side causing the defect from the roll pair based on the cycle in which the defect appears, and cleaning the roll on the identified side by the roll cleaning means. Film manufacturing equipment. The roll cleaning means has a cleaner head that presses a cleaning member against the roll,
The cleaner head is shorter than the effective width of the roll to be cleaned,
A head moving means for moving the cleaner head in the width direction of the roll to be cleaned,
The film inspection machine, it is possible to identify the position of the film in the width direction of the defect,
The cleaner head is moved to a position in the width direction of the roll corresponding to the position specified by the film inspecting machine, and a cleaning member is pressed against a corresponding portion of the roll to clean the specified roll. 1. The film manufacturing apparatus according to 1. 3. The film manufacturing apparatus according to claim 1, wherein the roll cleaning means contains water and can effectively remove the protein attached to the roll. 4. The film manufacturing apparatus according to claim 1, wherein the roll pair is a roll pair in which a molten resin extruded from a die attached to an extruder first comes into contact with the roll pair. Using the film manufacturing apparatus according to any one of claims 1 to 4,
During the preparatory stage of film production and/or during film production, the molten resin extruded from the extruder is sandwiched between the roll pairs to form a film-like resin, and the film-like resin is inspected by a film inspecting machine for defects. A method for producing a film, which comprises detecting and identifying the roll on the side causing the defect based on the cycle in which the defect appears, and cleaning the identified roll by a roll cleaning means. A resin in a molten state extruded from an extruder is sandwiched by a pair of rolls to form a film in a film manufacturing method,
At least two rolls forming the roll pair have different circumferential lengths, and a film inspection machine for detecting a defect generated in the film is disposed on the downstream side of the roll pair, and a roll for cleaning the rolls forming the roll pair. Equipped with cleaning means,
During the preparatory stage of film production and/or during film production, the molten resin extruded from the extruder is sandwiched between the roll pairs to form a film-like resin, and the film-like resin is inspected by a film inspecting machine for defects. A film manufacturing method comprising: detecting and identifying the roll on the side causing the defect from the pair of rolls based on the cycle in which the defect appears, and cleaning the identified roll by a roll cleaning means. The roll cleaning means has a cleaner head that presses a cleaning member against the roll,
The cleaner head is shorter than the effective width of the roll to be cleaned,
It has a head moving means for moving the cleaner head in the width direction of the roll to be cleaned,
The film inspection machine, it is possible to identify the position of the film in the width direction of the defect,
Characterized in that the cleaner head is moved by the head moving means to a position in the width direction of the roll corresponding to the position specified by the film inspecting machine, and the cleaning member is pressed against the corresponding part of the roll to clean the roll. The film manufacturing method according to claim 6. 8. The film manufacturing method according to claim 6, wherein the roll cleaning means contains water and is capable of effectively removing the protein attached to the roll. During or after cleaning the roll with the cleaning member, continue or restart the detection of defects occurring in the film,
9. The film manufacturing method according to claim 5, wherein the defect occurrence cycle and the width direction position before the cleaning are compared with the defect occurrence cycle and the width direction position after the cleaning.

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