TW202146545A - Method for manufacturing resin film, and pre-cut film - Google Patents

Abstract

Provided is a method for manufacturing a resin film, the method comprising: a step for applying a first resin composition solution onto a center section of a support body and applying a second resin composition solution onto both end sections; a step for drying the first resin composition solution and the second resin composition solution to obtain a pre-cut film; a step for detaching the pre-cut film from the support body; a step for conveying the pre-cut film in a state in which both ends of the pre-cut film are gripped by a tenter-type conveying device; and a step for removing, from the pre-cut film, a portion formed from the second resin composition solution, and obtaining a resin film. In the pre-cut film, the tearing strength of the portion formed from the second resin composition solution is greater than the tearing strength of a portion formed from the first resin composition solution.

Description

Manufacturing method of resin film, and film before cutting

The present invention relates to a method for producing a resin film and a film before cutting.

It is known that in the film production process, when conveying, drying, heat-treating the film, etc., both ends in the width direction of the film are sandwiched by a large number of needles or clamps, and the opposite ends of the film are oriented relative to the film. A tenter-type conveying device that conveys in a state where tension is applied in the width direction (for example, refer to Patent Document 1).

There are several conveying methods for tenter-type conveying devices. Among these conveying methods, a needle-comb tenter-type conveying device that clamps the film by puncturing the two ends of the film with a large number of needles along the flow direction has a large number of needles, which are arranged on a To the needle plate supported by the moving chains arranged parallel to each other. When the shrinkage force (stretching force) of the film is increased in this pin tenter type conveying device, there is a problem that the hole formed in the film by the needle puncture is broken into long holes in the width direction of the film. Wait. When the holes formed in the film are ruptured, the film cannot be maintained in a properly pulled state, and as a result, a reduction in quality such as wrinkles is caused in the film. As a result, the breakage of the hole becomes the cause of production loss, and at the same time, it brings about the reduction of production efficiency. In addition, even in the case of using a tenter-type conveyer that clamps both ends with clamps, there is the same problem as in the case of using a pin tenter-type conveyer that the portion of the film clamped by the clamps is broken. .

Conventionally, in order to solve this problem, it has been proposed to laminate a film with a high tear strength on a sandwich portion (edge portion) of a film with a low tear strength as a reinforcing film (refer to Patent Document 2). Moreover, when conveying a sheet etc., it is proposed that the density of the inner side in the width direction is higher than the density of the outer side with respect to the arrangement density of the needles at both ends of the sheet (see Patent Document 3). [Prior Art Literature] [Patent Literature]

[Patent Document 1] Japanese Patent Publication No. 39-29211 [Patent Document 2] Japanese Patent Application Laid-Open No. 11-254521 [Patent Document 3] Japanese Patent Application Laid-Open No. 9-77315

[The problem to be solved by the invention]

However, in the method of Patent Document 2, since a film with a low tear strength is laminated with a film with a high tear strength, there is a problem that the waste of raw materials increases. That is, the nip portion is a portion to be torn apart and discarded sooner or later after conveyance, and if the nip portion is constructed in two layers, there is a problem that the portion to be discarded increases. In addition, the method of Patent Document 3 cannot cope with the case of a film having a lower tear strength, and there is a problem in that the hole formed in the film is broken due to needle puncture.

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a method for producing a resin film capable of more effectively suppressing breakage of the film when both ends of the film are sandwiched by a tenter-type conveying device, and a cutting Film before breaking. [means to solve the problem]

The inventors of the present invention have conducted intensive research on a method for producing a resin film and a film before cutting. As a result, the inventors found that the following configuration can more effectively suppress the rupture of the film when both ends of the film are sandwiched by a tenter-type conveying device, thereby completing the present invention.

That is, the manufacturing method of the resin film of the present invention is characterized by having: Step A, which is to coat the first resin composition solution on the central part of the support, Step B, which is to coat the second resin composition solution on both ends adjacent to the central portion, Step C, which is to dry the first resin composition solution and the second resin composition solution to obtain a film before cutting, Step D, which is to peel off the aforementioned film from the aforementioned support body before cutting, Step E, after the aforementioned Step D, the two ends of the aforementioned film before being cut are clamped by a tenter-type conveying device, Step F, which is to convey the film before cutting in a state where both ends of the film before cutting are sandwiched, and Step G, after the aforementioned step F, removing the portion formed by the aforementioned second resin composition solution from the aforementioned pre-cutting film to obtain a resin film; The tear strength of the portion of the pre-cut film after the aforementioned step C and before the aforementioned step F formed from the second resin composition solution is higher than the tear strength of the portion formed from the first resin composition solution. big.

With the above configuration, the first resin composition solution is applied to the central portion of the support (step A), and the second resin composition solution is applied to both ends (step B), so that the first resin composition solution is applied. The solution and the second resin composition solution are dried to obtain a film before cutting (step C). The both ends of the film before cutting thus obtained are formed only from the second resin composition solution. Here, the tear strength of the part formed only from the said 2nd resin composition solution is larger than the tear strength of the part formed from the said 1st resin composition solution. Therefore, even if it is conveyed in the state which clamped the both ends of the said pre-cutting film by the tenter type conveyance apparatus (step F), it is hard to generate|occur|produce the crack of a clamp part (both ends). Moreover, according to the said structure, after the said step F, the part formed by the said 2nd resin composition solution is removed from the said pre-cutting film, and a resin film is obtained (step G). By such a method, even a resin film having a low tear strength can be conveyed using a conventionally known tenter-type conveying device. Moreover, since the both ends of the film before cutting are only the portion formed by the second resin composition solution, waste of the raw material of the portion removed by the step G can be minimized.

In the aforementioned configuration, the aforementioned step E is preferably a step of sandwiching both ends of the aforementioned film before cutting with needles of a pin tenter-type conveying device.

The tear strength of the portion of the pre-cutting film formed from the first resin composition solution is higher than the tear strength of the portion formed from the second resin composition solution, so that pinching can be suppressed more ideally. Cracks caused by needles of tenter-type conveyors.

In the above configuration, the resin film is preferably a polyimide resin film.

In recent years, there has been a high demand for a polyimide-based resin film with high transparency, and such a polyimide-based resin film tends to have low tear strength. Therefore, with the above-mentioned configuration, it is particularly desirable to obtain a polyimide-based resin film having a low tear strength.

In addition, the film before cutting of the present invention is characterized by having: a central portion, which is composed of the first resin composition, and Both ends, which are formed continuously from the central portion at both ends of the central portion, The both ends are made of a second resin composition different from the first resin composition, The tear strength of the both end portions is greater than the tear strength of the central portion.

With the above-described configuration, the tear strength of both end portions is larger than that of the center portion, so even in a state where both end portions of the film before cutting are sandwiched by a tenter-type conveying device It is also difficult to break the clamped portion (both ends) during transportation. In addition, since both ends of the film before cutting are composed of only the second resin composition, when removing both ends to obtain a resin film, it is possible to minimize waste of raw materials in the removed portion.

In the above configuration, the first resin composition is preferably a polyimide resin.

When the above-mentioned first resin composition is a polyimide-based resin, it is desirable to obtain a polyimide-based resin film having a low tear strength by removing both ends after being conveyed by a tenter-type conveying device. . [Effect of invention]

According to the present invention, there can be provided a method for producing a resin film and a film before cutting, which can more effectively suppress breakage of the film when both ends of the film are sandwiched by a tenter-type conveying device.

[Form for carrying out the invention]

Embodiments of the present invention will be described below.

[Manufacturing method of resin film] The manufacturing method of the resin film of this embodiment has: Step A, which is to coat the first resin composition solution on the central part of the support, Step B, which is to coat the second resin composition solution on both ends adjacent to the central portion, Step C, which is to dry the first resin composition solution and the second resin composition solution to obtain a film before cutting, Step D, which is to peel off the aforementioned film from the aforementioned support body before cutting, Step E, after the aforementioned Step D, the two ends of the aforementioned film before being cut are clamped by a tenter-type conveying device, Step F, which is to convey the film before cutting in a state where both ends of the film before cutting are sandwiched, and Step G, after the aforementioned step F, removing the portion formed by the aforementioned second resin composition solution from the aforementioned pre-cutting film to obtain a resin film; The tear strength of the portion of the pre-cut film after the aforementioned step C and before the aforementioned step F formed from the second resin composition solution is higher than the tear strength of the portion formed from the first resin composition solution. big.

<Step A, Step B> In the manufacturing method of the resin film of this embodiment, first, the 1st resin composition solution is apply|coated to the center part of a support body (step A). Moreover, the 2nd resin composition solution is apply|coated to the both ends adjacent to the said center part (step B). The aforementioned step A and the aforementioned step B may be performed simultaneously, or the aforementioned step B may be performed after the aforementioned step A, or the aforementioned step A may be performed after the aforementioned step B is performed.

The support is not particularly limited, but is preferably one having resistance to the solvent of the first resin composition solution and the second resin composition solution, for example, PET (polyethylene terephthalate) General resin films, metal rollers, steel endless belts, etc.

The coating methods of the aforementioned step A and the aforementioned step B are not particularly limited, for example, a corner wheel coating method, a T die coating method, a spin coating method, a spraying method, a bar coating method, a knife coating method, a dipping method, etc. are mentioned. It is also possible to combine 2 methods from among them. It is preferable from the viewpoint of productivity as long as it is a notch coating method, a T-die coating method, or a combination of these.

Specific examples of Step A and Step B will be described below.

[1st Embodiment] Fig. 1 is a side sectional view for explaining the coating method of the resin composition solution according to the first embodiment, and Fig. 2 is a plan view thereof. As shown in FIGS. 1 and 2 , the coating apparatus 10 includes a backing roller 12 , a cutaway roller 14 , and three coating liquid storage portions 16 ( 16 a , 16 b , and 16 c ). The coating liquid storage portion 16 ( 16 a , 16 b , 16 c ) has four side plates 18 ( 18 a , 18 b , 18 c , 18 d ) for dividing the coating liquid storage portion 16 , and a back plate 20 . The coating liquid storage portion 16 ( 16 a , 16 b , 16 c ) can store the coating liquid 62 in the region surrounded by the back plate 20 and the side plate 18 .

Among the three coating liquid storage portions 16 (16a, 16b, 16c), the coating liquid storage portions 16a, 16c located on both end sides store the second resin composition solutions 62a, 62c, and the coating liquid storage portion 16b located at the center stores the The first resin composition solution 62b.

The back roller 12 continuously conveys the support body 60 by rotating. The support body 60 conveyed by the back roller 12 passes through the gap 22 formed between the back roller 12 and the cutaway roller 14 . When the support 60 passes through the gap 22, the coating liquid 62 (the second resin composition solutions 62a, 62c, and the first resin composition solution 62b) is supplied from the coating liquid storage unit 16 onto the support 60 to form the coating film 64 (64a). , 64b, 64c). Specifically, the coating film 64 having a thickness corresponding to the thickness of the support body 60 being subtracted from the gap 22 is formed.

The thickness of the coating film 64 can be controlled by the gap 22 and the like between the backing roller 12 and the cut-out roller 14 .

FIG. 3 is a partially enlarged plan view of the vicinity of the side plate 18b shown in FIG. 2 . Each coating liquid 62 (the second resin composition solutions 62a, 62c, and the first resin composition solution 62b) is applied to the support 60, and then spreads in the width direction. Specifically, as shown in FIG. 3 , the second resin composition solution 62a applied in the vicinity of the side plate 18b spreads inward in the width direction (right side in FIGS. 2 and 3 ). On the other hand, the first resin composition solution 62b applied in the vicinity of the side plate 18b spreads outward in the width direction (left side in FIGS. 2 and 3 ). Furthermore, the second resin composition solution 62a (coating film 64a) is connected to the first resin composition solution 62b (coating film 64b) at the non-side plate 18b in the flow direction (upper side in FIGS. 2 and 3). Similarly, the 1st resin composition solution 62b apply|coated in the vicinity of the side plate 18c spreads to the width direction outer side (right side in FIG. 2). On the other hand, the second resin composition solution 62c applied in the vicinity of the side plate 18c spreads inward in the width direction (left side in FIG. 2). Moreover, the 1st resin composition solution 62b (coating film 64b) and the 2nd resin composition solution 62c (coating film 64c) are connected in the non-side board 18c in the flow direction. By the above, the coating film 64a is connected to the coating film 64b, and at the same time, the coating film 64b is connected to the coating film 64c. The aforementioned connection includes the case where the resin composition solutions constituting the respective coating films 64 are mutually dissolved and connected, and the case where the connection is performed by the adhesive force in the interface of the respective coating films 64, and the like.

The connection state of each coating film 64 is not particularly limited, and examples include: the case where each coating film is connected only on the side surface (see FIG. 4 ), and the case where one coating film is slightly overlapped on the other coating film (see FIG. 4 ) Figure 5, Figure 6).

FIG. 4 is a cross-sectional view showing a state where each coating film is connected only by the side surface. In the example shown in FIG. 4, the coating film 64a and the coating film 64b are connected only by the side surfaces. Moreover, the coating film 64b and the coating film 64c are connected only by the side surface. Immediately after coating, only the side surfaces are connected, and immediately before the subsequent step C is performed by mixing the second resin composition solution 62a (coating film 64a) and the first resin composition solution 62b (coating film 64b), or the first resin composition The composition solution 62b (coating film 64b ) and the second resin composition solution 62c (coating film 64c ) were formed to produce a composition gradient region. The width of the aforementioned compositionally graded region is preferably in the range of 10 to 2500 times the thickness of the coating film 64b in the non-compositionally graded region. More preferably, it is 100 to 1,000 times, and even more preferably, it is 250 to 500 times. For example, when the thickness of the coating film 64b is 20 μm, the width of the aforementioned composition gradient region is preferably 0.2 mm (10 times the thickness of the coating film 64b) to 5 cm (2500 times the thickness of the coating film 64b). As long as it is within this range, cracks from the compositionally graded region are less likely to occur during manufacture.

FIG. 5 is a cross-sectional view showing a state where the coating film 64a and the coating film 64c are slightly overlapped on the coating film 64b. In the example shown in FIG. 5, the edge part of the coating film 64a overlaps a little on the coating film 64b. Moreover, the edge part of the coating film 64c overlaps a little on the coating film 64b. The repeating part is composed of the second resin composition solution 62a (coating film 64a) and the first resin composition solution 62b (coating film 64b), or the first resin composition solution 62b (coating film 64b) and the second resin The compound solution 62c (coating film 64c) is mixed to form a composition gradient region. The width of the aforementioned compositionally graded region is preferably in the range of 10 to 2500 times the thickness of the coating film 64b in the non-compositionally graded region. More preferably, it is 100 to 1,000 times, and even more preferably, it is 250 to 500 times. For example, when the thickness of the coating film 64b is 20 μm, the width of the aforementioned composition gradient region is preferably 0.2 mm (10 times the thickness of the coating film 64b) to 5 cm (2500 times the thickness of the coating film 64b). As long as it is within this range, cracks from the compositionally graded region are less likely to occur during manufacture.

FIG. 6 is a cross-sectional view showing a state where the coating film 64b is slightly overlapped on the coating film 64a and the coating film 64c. In the example shown in FIG. 6, the edge part (end part on the left side in FIG. 6) of the coating film 64b overlaps a little on the coating film 64a. Moreover, the edge part (the edge part on the right side in FIG. 6) of the coating film 64b overlaps a little on the coating film 64c. As an example of the width of the overlapping portion, it is the same as in the case of FIG. 5 , and it is preferably in the range of 10 to 2500 times the width of the coating film 64b in the portion that does not constitute the gradation region. More preferably, it is 100 to 1,000 times, and even more preferably, it is 250 to 500 times. As long as it is within this range, cracks from the compositionally graded region are less likely to occur during manufacture.

The aforementioned connection state can be determined by, for example, the gap 22 . As long as the gap 22 through which the second resin composition solutions 62a and 62c pass, and the gap 22 through which the first resin composition solution 62b passes are the same, the connection state as shown in FIG. 4 can be easily achieved. As long as the gap 22 through which the second resin composition solutions 62a and 62c pass is set slightly wider than the gap 22 through which the first resin composition solution 62b passes, the connection state as shown in FIG. 5 can be easily achieved. As long as the gap 22 through which the first resin composition solution 62b passes is set slightly wider than the gap 22 through which the second resin composition solutions 62a and 62c pass, the connection state as shown in FIG. 6 can be easily achieved. In addition, the aforementioned connection state can be controlled not only by the gap 22 but also by the viscosity of the first resin composition solution 62b, the second resin composition solutions 62a, 62c, and the width of the side plate 18.

In the first embodiment, Step A and Step B are simultaneously performed by the coating apparatus 10 described above.

Step A and Step B of the first embodiment have been described above.

[Second Embodiment] FIG. 7 is a side sectional view for explaining the coating method of the resin composition solution according to the second embodiment, and FIG. 8 is a plan view thereof. In addition, about the structure common to the coating apparatus 30 of 2nd Embodiment and the coating apparatus 10 of 1st Embodiment, the same code|symbol is attached|subjected and description is abbreviate|omitted or simplified.

As shown in FIGS. 7 and 8 , the coating device 30 includes a backing roller 12 , a cutaway roller 14 , and two coating liquid storage portions 16 ( 16 a , 16 c ) on both sides in the width direction. The coating liquid storage portion 16 ( 16 a , 16 c ) can store the coating liquid 62 in the region surrounded by the back plate 20 and the side plate 18 .

The two coating liquid storage parts 16 (16a, 16c) store the second resin composition solutions 62a, 62c. In addition, unlike 1st Embodiment, in the coating apparatus 30 of 2nd Embodiment, the 1st resin composition solution is not stored in the coating liquid storage part 16.

The back roller 12 continuously conveys the support body 60 by rotating. The support body 60 conveyed by the back roller 12 passes through the gap 22 formed between the back roller 12 and the cutaway roller 14 . When the support 60 passes through the gap 22 , the second resin composition solutions 62 a and 62 c are supplied from the coating liquid storage unit 16 onto the support 60 to form the coating films 64 a and 64 c.

The coating device 30 further includes a T-die coater 32 . The T-die coater 32 is installed at the rear stage of the back roller 12 and the cutaway roller 14 . The T-die coater 32 is installed so that the discharge port is located above the center portion of the support body 60 .

When the support body 60 after forming the coating films 64 a and 64 c is conveyed, the T-die coater 32 applies the first resin composition solution 62 b to the center portion of the support body 60 .

In the second embodiment, using the coating apparatus 30 described above, first, step B is performed first, and thereafter, step A is performed. In the case of the second embodiment, the connection state of each coating film 64 is likely to be the connection state shown in FIG. 6 , but it is not limited to this. In addition, as a modification of the second embodiment, the first resin composition solution may be applied to the center of the support by a notch coater, and then the second resin composition may be applied by a T-die coater. The chemical solution was applied to both ends.

Step A and Step B of the second embodiment have been described above.

[third embodiment] Fig. 9 is a side sectional view for explaining the coating method of the resin composition solution according to the third embodiment, and Fig. 10 is a plan view thereof. In addition, about the structure common to the coating apparatus 30 of 2nd Embodiment in the coating apparatus 40 of 3rd Embodiment, the same code|symbol is attached|subjected and description is abbreviate|omitted or simplified.

The coating apparatus 40 includes a T-die coater 42a, a T-die coater 42b, and a T-die coater 42c. The T-die coater 42a and the T-die coater 42c are installed before the T-die coater 42b. The T-die coater 42a and the T-die coater 42c are installed so that the discharge port is located above the end of the support body 60, respectively. In FIG. 10 , the T-die coater 42 a is installed so that the discharge port is located above the left end of the support body 60 , and the T-die coater 42 c is installed so that the discharge port is located above the right end of the support body 60 . The T-die coater 42b is installed so that a discharge port may be located above the center part of the support body 60 .

When the support body 60 on which the coating films 64 a and 64 c are formed is conveyed, the T-die coater 42 b applies the first resin composition solution 62 b to the center portion of the support body 60 .

In the case of the third embodiment, the bonding state of each coating film 64 is likely to be the bonding state shown in FIG. 5 , but it is not limited to this. Furthermore, as a modification of the third embodiment, the second resin composition may be applied to both ends by a T-die coater, and then the first resin composition may be applied to the center by a T-die coater. . At this time, the bonding state of each coating film 64 is likely to be the bonding state shown in FIG. 6 , but is not limited to this. Furthermore, as another modification example, the second resin composition may be applied to the end portion of one side by a T-die coater, and then the first resin composition may be applied to the center portion by a T-die coater, and then, The second resin composition was applied to the one-side end portion with a T-die coater on the other one-side end portion. At this time, the bonding state of each coating film 64 is likely to be the bonding state shown in FIG. 11 , but is not limited to this. In the example shown in FIG. 11, the edge part of the coating film 64a overlaps a little on the coating film 64b. Moreover, the edge part (the edge part on the right side in FIG. 11) of the coating film 64b overlaps a little on the coating film 64c. As shown in the third embodiment and its modification, steps A and B may be a form in which a plurality of T-die coaters are arranged in a row, and the first resin composition and the second resin composition are sequentially applied.

[4th Embodiment] Fig. 12 is a side sectional view for explaining the coating method of the resin composition solution according to the fourth embodiment, and Fig. 13 is a plan view thereof. In addition, about the structure common to the coating apparatus 50 of 4th Embodiment and the coating apparatus 40 of 3rd Embodiment, the same code|symbol is attached|subjected and description is abbreviate|omitted or simplified.

The coating apparatus 50 is provided with the T-die coater 52 which has the discharge port divided into three in the width direction. The T-die coater 52 applies the first resin composition to the central portion of the support body 60 and simultaneously applies the second resin composition to both ends.

As shown in FIGS. 12 and 13 , the step A and the step B in the fourth embodiment are forms in which the first resin composition and the second resin composition are applied simultaneously. In the case of the fourth embodiment, the bonding state of each coating film 64 is likely to be the bonding state shown in FIG. 4 , but it is not limited to this.

<Step C> After the step A and the step B, the first resin composition solution and the second resin composition solution are dried to obtain a film before cutting (step C). The drying conditions can be appropriately set within the range in which the solvent can be sufficiently volatilized, and as an example, the drying temperature can be set within the range of 60° C. to 140° C. and the drying time within the range of 1 minute to 60 minutes. The aforementioned drying conditions, especially when dimethylacetamide is used as the solvent, are preferable because the boiling point is 165°C. After step C and before step D, the step of winding the above-mentioned pre-cutting film together with the above-mentioned support body into a roll (step C-1) may be performed. In this case, before step D, the above-mentioned pre-cutting film may be rewound again.

<Step D> After the aforementioned step C, the aforementioned pre-cutting film is peeled off from the aforementioned support body (step D). The method of peeling off the film before cutting from the support is not particularly limited, and can be used: a method of rolling up from the end with tweezers or the like; making a notch on the film before cutting, and attaching the tape before cutting. The method of rolling up from the tape part after one side of the cut part; the method of rolling up from the part after one side of the cut part of the film before cutting by vacuum suction, etc. As a method of rolling up, it is preferable to roll up while winding up as a roll. As a method of making a notch on the film before cutting, there are: a method of cutting the film before cutting with a cutting tool such as a cutting tool; and a method of cutting the film before cutting with a laser; The method of cutting the film before cutting by a water jet is not particularly limited. For example, when the above-mentioned method is employed, methods such as superimposing ultrasonic waves on the cutting tool, adding back-and-forth motions, and up-and-down motions to improve cutting performance can also be appropriately employed. After the step D and before the step E, the step of winding the above-mentioned pre-cutting film into a roll (step D-1) may be performed. In this case, before step E, what is necessary is just to rewind the said film before cutting|disconnection. When winding the above-mentioned pre-cutting film, it is preferable to wind the film with a laminated paper (anti-blocking film) therebetween. As long as the steps of the above-mentioned step C-1 and/or the above-mentioned D-1 are carried out, it becomes possible to set a certain period of time after the drying step (step C) until the cutting step (step G) is carried out. By winding the cut film once after the drying step (step C), and maintaining the state for a certain period of time, the solvent distribution in the thickness direction of the film can be equalized. This point will be described below. As shown in Fig. 5 and Fig. 6 , when two coating films are slightly overlapped, the solvent distribution in the film immediately after drying on the support is that the residual amount of solvent in the coating film on the support side is higher than that in the coating film on the surface side. More remains. When a heating step (for example, step F to be described later) is performed in this state, the amount of solvent volatilization varies, and there is a possibility that the portion (overlapping portion) is likely to be cracked. Here, by carrying out the aforementioned step C-1 and/or the aforementioned D-1, the solvent distribution in the thickness direction of the repeating portion is equalized, the residual amount of the solvent in the two coating films becomes more equal, and the repeating portion is not easily broken. . The period of holding in the rolled state after the aforementioned step C-1 and/or after the aforementioned step D-1 is preferably 30 minutes or more, and more preferably 3 hours or more. When the above-mentioned period is maintained in the rolled state, the solvent can be ideally diffused in the thickness direction. Moreover, if the said process C-1 and/or the said D-1 is implemented, since the said pre-cutting film is wound once in the middle of a process, it becomes possible to make a production apparatus compact. That is, when all the steps are continuously connected, the production line becomes quite long, and there are cases in which limitations such as factory site selection occur. On the other hand, if the winding step is carried out in the middle of the production, the production line can be divided into two, and the two divided production lines can be arranged in parallel, and a relatively compact production apparatus can be produced. Furthermore, it becomes possible to perform quality inspection in a step by winding once in the middle of production.

<Step E> After the aforementioned step D, both ends of the aforementioned film before being cut are clamped by a tenter-type conveying device (step E). Specifically, when a pin tenter-type conveying device is used as the tenter-type conveying device, two of the aforementioned pre-cutting films are held by puncturing with a plurality of needles of the pin- tenter-type conveying device. Ends. Furthermore, when a clip-type tenter-type conveying device is used as the tenter-type conveying device, both ends of the film before cutting are clamped by being sandwiched by a plurality of clips of the clip-type tenter-type conveying device. Department. As a tenter-type conveying apparatus, a conventionally known one (for example, the tenter-type conveying apparatus disclosed in Japanese Patent No. 4843996, Japanese Patent No. 4821960, etc.) can be used.

<Step F> After the said step E, the said pre-cutting film is conveyed in the state which pinched the both ends of the said pre-cutting film (step F). It can also be heated during transportation. The heating temperature is not particularly limited, and when the first resin composition solution and the second resin composition solution are polyimide-based resin composition solutions, for example, it can be set to 150°C to 500°C for 1 minute to 60°C. within minutes. In addition, in step E and step F, the film before cutting may be extended in the longitudinal direction and/or the width direction, or may not be extended.

In the aforementioned step F, the aforementioned pre-cutting film is usually shrunk in the width direction during conveyance. Therefore, the stretching tension becomes applied to the portion held by the tenter-type conveying device. Here, the details will be described later, but the tear strength of the film at both ends (the part formed from the second resin composition solution) before cutting is higher than the tear strength of the central part (the part formed from the second resin composition solution) greater crack strength. Therefore, the breakage of the aforementioned pre-cutting film in the sandwiched portion (both end portions) is suppressed. In particular, when a pin tenter-type conveying device is used as the tenter-type conveying device, it is more desirable to suppress breakage caused by the needles of the pin tenter-type conveying device.

<Step G> After the above-mentioned step F, the portion formed by the above-mentioned second resin composition solution is removed from the above-mentioned pre-cutting film to obtain a resin film (step G). In step G, at least the portion formed by the second resin composition solution may be removed, and the portion formed by the second resin composition solution may be removed at the same time as the portion formed by the first resin composition. The portion formed from the composition solution. The said resin film obtained in this way becomes the part which consists only of the said 1st resin composition solution. That is, a resin film containing only a portion having a low tear strength is obtained.

The thickness of the resin film is not particularly limited, but is preferably 5 μm to 125 μm, more preferably 7.5 μm to 75 μm, and even more preferably 12.5 μm to 50 μm.

It does not specifically limit as a method of removing the part which consists of the said 2nd resin composition solution from the said pre-cutting film, A conventionally well-known cutter etc. can be used.

As described above, even a resin film having a low tear strength can be conveyed using a conventionally known tenter-type conveying device as long as the method for producing a resin film of the present embodiment is used. Moreover, since the both ends of the film before cutting are the parts formed only from the second resin composition solution, waste of the raw material of the part removed by the step G can be minimized.

Hereinafter, the said 1st resin composition solution and the said 2nd resin composition solution are demonstrated.

The first resin composition solution and the second resin composition solution, as long as it is the part formed by the second resin composition solution in the pre-cutting film after the step C and before the step F. The tear strength becomes larger than the tear strength of the part which consists of the said 1st resin composition solution, and is not specifically limited.

As said 1st resin composition solution, a polyimide-type resin composition solution, a polyimide-type resin composition solution, a polyimide-imide-type resin composition solution, etc. are mentioned. Among them, the polyimide resin composition solution is preferred. Among the polyimide-based resin films, those generally called transparent polyimide are often weak in tearing strength, but as long as the method for producing the resin film of the present embodiment is used, even those with weak tearing strength can be obtained. A transparent polyimide-based resin film can also be suitably produced.

The first polyimide resin composition solution may be a polyimide (polyimide precursor) solution or a polyimide solution. When a polyimide solution is used, a dehydration ring-closure reaction is performed by performing heat treatment in step F to form a polyimide film. When a polyimide solution is used, a thin film of polyimide is formed by volatilizing the solvent in step C.

The aforementioned polyamic acid solution is obtained by reacting diamines and tetracarboxylic acids in a solvent.

As the aforementioned tetracarboxylic acids, aromatic tetracarboxylic acids (including acid anhydrides thereof), aliphatic tetracarboxylic acids (including acid anhydrides thereof), and alicyclic tetracarboxylic acids (including acid anhydrides thereof) commonly used in the synthesis of polyimide can be used ). Among them, aromatic tetracarboxylic anhydrides and alicyclic tetracarboxylic anhydrides are more preferable, and from the viewpoint of heat resistance, aromatic tetracarboxylic anhydrides are more preferable, and from the viewpoint of light transmittance, More preferably, alicyclic tetracarboxylic acids are used. When these are acid anhydrides, the anhydride structure in the molecule may be one or two, but it is preferably one having two anhydride structures (dianhydride). Tetracarboxylic acids may be used alone or in combination of two or more.

Among the above-mentioned polyimide solutions, it is preferable to obtain a solution of polyimide with high colorless transparency.

Examples of aromatic tetracarboxylic acids for obtaining polyimide with high colorless transparency include 4,4'-(2,2-hexafluoroisopropylidene)diphthalic acid, 4,4'- -Oxydiphthalic acid, 3,4'-oxydiphthalic acid, bis(1,3-dioxy-1,3-dihydro-2-benzofuran-5-carboxylic acid ) 1,4-phenylene ester, bis(1,3-dioxy-1,3-dihydro-2-benzofuran-5-yl)benzene-1,4-dicarboxylate, 4,4 '-[4,4'-(3-Oxy-1,3-dihydro-2-benzofuran-1,1-diyl)bis(benzene-1,4-diyloxy)]di Benzene-1,2-dicarboxylic acid, 4,4'-[(3-oxy-1,3-dihydro-2-benzofuran-1,1-diyl)bis(toluene-2,5 -Diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[(3-oxy-1,3-dihydro-2-benzofuran-1,1-diyl ) bis(1,4-xylene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[4,4'-(3-side oxygen-1 ,3-Dihydro-2-benzofuran-1,1-diyl)bis(4-isopropyl-toluene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[4,4'-(3-oxy-1,3-dihydro-2-benzofuran-1,1-diyl)bis(naphthalene-1,4-diyloxy) )] diphenyl-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benzothiol-1,1-dioxide-3,3-dioxide base)bis(benzene-1,4-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-benzophenonetetracarboxylic acid, 4,4'-[(3H-2 ,1-Benzothiol-1,1-dioxide-3,3-diyl)bis(toluene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4 ,4'-[(3H-2,1-benzothiol-1,1-dioxide-3,3-diyl)bis(1,4-xylene-2,5-diyloxy) )] diphenyl-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1-benzothiol-1,1-dioxide-3,3-dioxide base)bis(4-isopropyl-toluene-2,5-diyloxy)]diphenyl-1,2-dicarboxylic acid, 4,4'-[4,4'-(3H-2,1 -Benzothiol-1,1-dioxide-3,3-diyl)bis(naphthalene-1,4-diyloxy)]diphenyl-1,2-dicarboxylic acid, 3,3 ',4,4'-benzophenone tetracarboxylic acid, 3,3',4,4'-diphenyltetracarboxylic acid, 3,3',4,4'-biphenyltetracarboxylic acid, 2, 3,3',4'-biphenyltetracarboxylic acid, 2,2',3,3'-biphenyltetracarboxylic acid, pyromellitic acid, 4,4'-[spiro(dibenzopyran-9 ,9'-Pylenol)-2,6-diylbis(oxycarbonyl)]diphthalic acid, 4,4'-[spiro(dibenzopyran-9,9'-Pylon)-3, 6-Diylbis(oxycarbonyl)]di-o-phenyl Tetracarboxylic acids such as dicarboxylic acid and acid anhydrides thereof. Among these, dianhydrides with two acid anhydride structures are preferred, especially 4,4'-(2,2-hexafluoroisopropylidene)diphthalic dianhydride, 4,4'-oxyl Diphthalic dianhydride is preferred. In addition, aromatic tetracarboxylic acids may be used alone or in combination of two or more. When emphasis is placed on heat resistance, the aromatic tetracarboxylic acid is preferably 50% by mass or more, more preferably 60% by mass or more, more preferably 70% by mass or more, still more preferably 80% by mass, for example, of all tetracarboxylic acids. above.

Examples of alicyclic tetracarboxylic acids include 1,2,3,4-cyclobutanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid, 1,2,3,4-cyclopentanetetracarboxylic acid Hexanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,3',4,4'-bicyclohexanetetracarboxylic acid, bicyclo[2,2,1]heptane- 2,3,5,6-Tetracarboxylic acid, Bicyclo[2,2,2]octane-2,3,5,6-tetracarboxylic acid, Bicyclo[2,2,2]oct-7-ene-2 ,3,5,6-Tetracarboxylic acid, Tetrahydroanthracene-2,3,6,7-tetracarboxylic acid, Tetrahydro-1,4:5,8:9,10-Trimethylanthracene-2,3 ,6,7-tetracarboxylic acid, decahydronaphthalene-2,3,6,7-tetracarboxylic acid, decahydro-1,4:5,8-dimethylnaphthalene-2,3,6,7-tetra Carboxylic acid, decahydro-1,4-ethano-5,8-naphthalene-2,3,6,7-tetracarboxylic acid, norbornane-2-spiro-α-cyclopentanone-α'- Spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid (alias "norbornane-2-spiro-2'-cyclopentanone-5'-spiro-2' '-norbornane-5,5'',6,6''-tetracarboxylic acid"), methylnorbornane-2-spiro-α-cyclopentanone-α'-spiro-2''-( Methylnorbornane)-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclohexanone-α'-spiro-2''-norbornane- 5,5'',6,6''-tetracarboxylic acid (alias "norbornane-2-spiro-2'-cyclohexanone-6'-spiro-2''-norbornane-5,5' ',6,6''-tetracarboxylic acid"), methylnorbornane-2-spiro-α-cyclohexanone-α'-spiro-2''-(methylnorbornane)-5,5 '',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cycloacetone-α'-spiro-2''-norbornane-5,5'',6,6'' -Tetracarboxylic acid, norbornane-2-spiro-α-cyclobutanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane Alkane-2-spiro-α-cycloheptanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α -Cyclooctanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclononanone-α' -Spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclodecanone-α'-spiro-2''- Norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cycloundecanone-α'-spiro-2''-norbornane-5, 5'',6,6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclododecanone-α'-spiro-2''-norbornane-5,5'',6, 6''-tetracarboxylic acid, norbornane-2-spiro-α-cyclotridecone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxyl Acid, norbornane-2-spiro-α-cyclotetradecone-α'-spiro-2''-norbornane-5,5'',6,6 ''-Tetracarboxylic acid, norbornane-2-spiro-α-cyclopentadecanone-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid , norbornane-2-spiro-α-(methylcyclopentanone)-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid, norbornane Tetracarboxylic acids such as alkane-2-spiro-α-(methylcyclohexanone)-α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic acid and the like and other acid anhydrides. Among them, dianhydrides with two acid anhydride structures are preferred, especially 1,2,3,4-cyclobutanetetracarboxylic acid dianhydride, 1,2,3,4-cyclohexanetetracarboxylic acid dihydride Anhydride, 1,2,4,5-cyclohexanetetracarboxylic dianhydride are preferred, 1,2,3,4-cyclobutanetetracarboxylic dianhydride, 1,2,4,5-cyclohexane Tetracarboxylic dianhydride is more preferred, and 1,2,3,4-cyclobutanetetracarboxylic dianhydride is further preferred. In addition, these may be used individually or in combination of 2 or more types. When transparency is important, the alicyclic tetracarboxylic acid is preferably 50% by mass or more, more preferably 60% by mass or more, still more preferably 70% by mass or more, and still more preferably 80% by mass, for example, of all tetracarboxylic acids. %above.

The aforementioned polyamic acid solution may also contain: tricarboxylic acids and dicarboxylic acids.

As tricarboxylic acids, trimellitic acid, 1,2,5-naphthalene tricarboxylic acid, diphenyl ether-3,3',4'-tricarboxylic acid, diphenylene-3,3',4 Aromatic tricarboxylic acids such as '-tricarboxylic acid, or hydrogenated products of the above-mentioned aromatic tricarboxylic acids such as hexahydrotrimellitic acid, ethylene glycol bis-trimellitate, propylene glycol bis-trimellitate, 1, Alkanediol bis-trimellitate such as 4-butanediol bis-trimellitate and polyethylene glycol bis-trimellitate, and monoanhydrides and esters thereof. Among these, monoanhydrides having one acid anhydride structure are preferred, especially trimellitic anhydride and hexahydrotrimellitic anhydride are preferred. In addition, these may be used individually or in combination of two or more.

Examples of the dicarboxylic acids include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, naphthalene dicarboxylic acid, and 4,4'-oxydiphenylcarboxylic acid, or 1,6 -Hydrogenates of the above aromatic dicarboxylic acids such as cyclohexanedicarboxylic acid, oxalic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, Undecanedioic acid, dodecanedioic acid, 2-methylsuccinic acid, and their acyl chlorides or esters, etc. Among these, aromatic dicarboxylic acids and their hydrides are preferred, and terephthalic acid, 1,6-cyclohexanedicarboxylic acid, and 4,4'-oxydiphenylcarboxylic acid are particularly preferred. In addition, the dicarboxylic acids may be used alone or in combination of two or more.

There are no particular limitations on the diamines or isocyanates for obtaining polyimide with high colorless transparency, and it can be used: usually used in the synthesis of polyimide, synthesis of polyimide, synthesis of polyimide Aromatic diamines, aliphatic diamines, alicyclic diamines, aromatic diisocyanates, aliphatic diisocyanates, alicyclic diisocyanates, etc. From the viewpoint of heat resistance, aromatic diamines are preferred, and from the viewpoint of transparency, alicyclic diamines are preferred. Moreover, when the aromatic diamine which has a benzoxazole structure is used, it becomes possible to express high elastic modulus, low thermal shrinkage property, and low linear expansion coefficient while expressing high heat resistance. Diamines and isocyanates may be used alone, or two or more of them may be used in combination.

Examples of aromatic diamines include 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,4-bis[2-(4-aminophenyl)-2- Propyl]benzene, 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl Benzene, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-aminophenoxy)biphenyl, bis[4-(3-aminophenoxy) ) phenyl] ketone, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-(3-aminophenoxy)phenyl]thiane, 2,2-bis[4 -(3-Aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoro Propane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzylamine, 4-amino-N-(4-aminophenyl)benzyl Amide, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 2,2'-trifluoromethyl-4 ,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl sulfide, 3,4'-diaminodiphenyl sulfide, 4,4'-diaminodiphenyl Sulfide, 3,3'-diaminodiphenylene, 3,4'-diaminodiphenylene, 4,4'-diaminodiphenylene, 3,3'- Diaminodiphenylene, 3,4'-diaminodiphenylene, 4,4'-diaminodiphenylene, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone Aminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4' -Diaminodiphenylmethane, bis[4-(4-aminophenoxy)phenyl]methane, 1,1-bis[4-(4-aminophenoxy)phenyl]ethane, 1,2-bis[4-(4-aminophenoxy)phenyl]ethane, 1,1-bis[4-(4-aminophenoxy)phenyl]propane, 1,2-bis [4-(4-Aminophenoxy)phenyl]propane, 1,3-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4- Aminophenoxy)phenyl]propane, 1,1-bis[4-(4-aminophenoxy)phenyl]butane, 1,3-bis[4-(4-aminophenoxy) ) phenyl]butane, 1,4-bis[4-(4-aminophenoxy)phenyl]butane, 2,2-bis[4-(4-aminophenoxy)phenyl] Butane, 2,3-bis[4-(4-aminophenoxy)phenyl]butane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-( 4-Aminophenoxy)-3-methylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)-3-methylphenyl]propane, 2-[4- (4-Aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4 -aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4- (4-Aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis (3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-( 4-Aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy)phenyl]sene , bis[4-(4-aminophenoxy)phenyl] bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-aminophenoxy) Phenyl] ether, 1,3-bis[4-(4-aminophenoxy)benzyl]benzene, 1,3-bis[4-(3-aminophenoxy)benzyl]benzene ] benzene, 1,4-bis[4-(3-aminophenoxy)benzyl]benzene, 4,4'-bis[(3-aminophenoxy)benzyl]benzene, 1,1-bis[4-(3-aminophenoxy)phenyl]propane, 1,3-bis[4-(3-aminophenoxy)phenyl]propane, 3,4'-bis Amino diphenyl sulfide, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, bis[4-( 3-Aminophenoxy)phenyl]methane, 1,1-bis[4-(3-aminophenoxy)phenyl]ethane, 1,2-bis[4-(3-aminobenzene] Oxy)phenyl]ethane, bis[4-(3-aminophenoxy)phenyl]thylene, 4,4'-bis[3-(4-aminophenoxy)benzyl ] diphenyl ether, 4,4'-bis[3-(3-aminophenoxy)benzyl]diphenyl ether, 4,4'-bis[4-(4-amino-α,α] -Dimethylbenzyl)phenoxy]benzophenone, 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy]diphenylene , bis[4-{4-(4-aminophenoxy)phenoxy}phenyl] , 1,4-bis[4-(4-aminophenoxy)phenoxy-α,α -Dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene, 1,3-bis[ 4-(4-Amino-6-trifluoromethylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-fluorobenzene] oxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-methylphenoxy)-α,α-dimethylbenzyl] ]benzene, 1,3-bis[4-(4-amino-6-cyanophenoxy)-α,α-dimethylbenzyl]benzene, 3,3'-diamino-4, 4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-diphenoxybenzophenone, 3,4'-diamino-4,5'-diamino Phenoxybenzophenone, 3,3'-diamino-4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone, 3,4' -Diamino-4-phenoxybenzophenone, 3,4'-diamino-5'-phenoxybenzophenone, 3,3'-diamino -4,4'-diphenyloxybenzophenone, 4,4'-diamino-5,5'-dibenzyloxybenzophenone, 3,4'-diamino-4 ,5'-diphenyloxybenzophenone, 3,3'-diamino-4-biphenoxybenzophenone, 4,4'-diamino-5-biphenoxybenzophenone Benzophenone, 3,4'-Diamino-4-biphenoxybenzophenone, 3,4'-Diamino-5'-biphenoxybenzophenone, 1,3-bis (3-Amino-4-phenoxybenzyl)benzene, 1,4-bis(3-amino-4-phenoxybenzyl)benzene, 1,3-bis(4-amine Benzyl-5-phenoxybenzyl)benzene, 1,4-bis(4-amino-5-phenoxybenzyl)benzene, 1,3-bis(3-amino-4- Biphenoxybenzyl)benzene, 1,4-bis(3-amino-4-biphenoxybenzyl)benzene, 1,3-bis(4-amino-5-biphenyl) Oxybenzyl)benzene, 1,4-bis(4-amino-5-biphenoxybenzyl)benzene, 2,6-bis[4-(4-amino-α,α) -Dimethylbenzyl)phenoxy]benzonitrile, 4,4'-[9H-pyridyl-9,9-diyl]bisaniline )”), spiro(dibenzopyran-9,9’-pyranyl)-2,6-diylbis(oxycarbonyl)]bisaniline, 4,4’-[spiro(dibenzopyran) -9,9'-Pylenol)-2,6-diylbis(oxycarbonyl)]bisaniline, 4,4'-[spiro(dibenzopyran-9,9'-pyrene)-3,6 -Diyl bis(oxycarbonyl)] bisaniline, and a part or all of the hydrogen atoms on the aromatic ring of the above-mentioned aromatic diamines are replaced by halogen atoms, alkyl or alkoxy groups having 1 to 3 carbon atoms, cyano groups, A halogenated alkyl group having 1 to 3 carbon atoms or an aromatic diamine substituted with an alkoxy group in which a part or all of the hydrogen atoms of an alkyl group or an alkoxy group is substituted with a halogen atom, and the like. Moreover, it does not specifically limit as the aromatic diamine which has the said benzoxazole structure, For example, 5-amino-2-(p-aminophenyl) benzoxazole, 6-amino- 2-(p-aminophenyl)benzoxazole, 5-amino-2-(m-aminophenyl)benzoxazole, 6-amino-2-(m-aminophenyl)benzoxazole azole, 2,2'-p-phenylene bis(5-aminobenzoxazole), 2,2'-p-phenylene bis(6-aminobenzoxazole), 1-(5-amine benzoxazolo)-4-(6-aminobenzoxazolo)benzene, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:5 ,4-d']bis oxazole, 2,6-(4,4'-diaminodiphenyl) benzo[1,2-d:4,5-d']bis oxazole, 2,6 -(3,4'-Diaminodiphenyl)benzo[1,2-d:5,4-d']bisoxazole, 2,6-(3,4'-diaminodiphenyl ) benzo[1,2-d:4,5-d']bisoxazole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:5,4 -d']Bisoxazole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole, etc. Among them, 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 4-amino-N-(4-aminophenyl)benzamide, 4,4'-diaminobenzophenone and 3,3'-diaminobenzophenone are preferable. In addition, aromatic diamines may be used alone or in combination of two or more.

Examples of alicyclic diamines include 1,4-diaminocyclohexane, 1,4-diamino-2-methylcyclohexane, 1,4-diamino-2-ethyl cyclohexane, 1,4-diamino-2-n-propylcyclohexane, 1,4-diamino-2-isopropylcyclohexane, 1,4-diamino-2-n-propylcyclohexane Butylcyclohexane, 1,4-diamino-2-isobutylcyclohexane, 1,4-diamino-2-secondarybutylcyclohexane, 1,4-diamino-2 -Tertiary butylcyclohexane, 4,4'-methylenebis(2,6-dimethylcyclohexylamine), etc. Among these, 1,4-diaminocyclohexane and 1,4-diamino-2-methylcyclohexane are particularly preferred, and 1,4-diaminocyclohexane is more preferred. In addition, alicyclic diamines may be used alone or in combination of two or more.

Examples of diisocyanates include diphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2'- or 4,3'- or 5,2' - or 5,3'- or 6,2'- or 6,3'-dimethyldiphenylmethane-2,4'-diisocyanate, 3,2'- or 3,3'- or 4,2 '- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-diethyldiphenylmethane-2,4'-diisocyanate, 3, 2'- or 3,3'- or 4,2'- or 4,3'- or 5,2'- or 5,3'- or 6,2'- or 6,3'-dimethoxydi Phenylmethane-2,4'-diisocyanate, Diphenylmethane-4,4'-diisocyanate, Diphenylmethane-3,3'-diisocyanate, Diphenylmethane-3,4'-diisocyanate , diphenyl ether-4,4'-diisocyanate, benzophenone-4,4'-diisocyanate, diphenylene-4,4'-diisocyanate, toluene-2,4-diisocyanate, toluene-2 ,6-diisocyanate, m-xylylene diisocyanate, p-xylylene diisocyanate, naphthalene-2,6-diisocyanate, 4,4'-(2,2bis(4-phenoxyphenyl) propane) diisocyanate, 3,3'- or 2,2'-dimethylbiphenyl-4,4'-diisocyanate, 3,3'- or 2,2'-diethylbiphenyl-4,4 '-diisocyanate, 3,3'-dimethoxybiphenyl-4,4'-diisocyanate, 3,3'-diethoxybiphenyl-4,4'-diisocyanate and other aromatic diisocyanates , and hydrogenated diisocyanates of any of these (eg: isophorone diisocyanate, 1,4-cyclohexanediisocyanate, 1,3-cyclohexanediisocyanate, 4,4'-dicyclohexyl Methane diisocyanate, hexamethylene diisocyanate) and the like. Among these, from the viewpoints of low hygroscopicity, dimensional stability, price, and polymerizability, diphenylmethane-4,4'-diisocyanate, toluene-2,4-diisocyanate, toluene-2 ,6-diisocyanate, 3,3'-dimethylbiphenyl-4,4'-diisocyanate and naphthalene-2,6-diisocyanate, 4,4'-dicyclohexylmethane diisocyanate, 1,4- Cyclohexane diisocyanate is preferred. In addition, the diisocyanates may be used alone or in combination of two or more.

As the above-mentioned solvent, as long as it can dissolve polyimide or polyimide precursor, an aprotic polar solvent or the like can be preferably used. For example, N,N-dimethylformamide, N,N-dimethylacetamide, N,N-diethylacetamide, N,N-dimethylmethoxyacetamide etc. N,N-di-lower alkylcarboxyamides, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, dimethyl sulfoxide, dimethyl sulfoxide, 1,3 - Dimethyl-2-imidazolidinone, γ-butyrolactone, diglyme, m-cresol, hexamethylphosphamide, N-acetyl-2-pyrrolidone, hexamethylphosphorus Amide, ethyl seleuronate, diethylene glycol dimethyl ether, cyclobutane, p-chlorophenol, etc. In addition, the solvent may be a mixture of two or more kinds.

The second resin composition solution is not particularly limited as long as it has a higher tear strength than the first resin composition solution at the time of film formation, and examples thereof include a polyimide-based resin composition solution, polyamide Amine resin composition solution, polyamide imide resin composition solution, etc. When a polyimide-based resin composition solution is used as the first resin composition solution, the polyimide-based resin composition solution is also used as the second resin composition from the viewpoint of closeness to heat resistance, etc. Physical solution is preferred. It is preferable that the second resin composition solution has heat resistance equal to or higher than that of the first resin composition solution.

The second polyimide resin composition solution may be a polyimide (polyimide precursor) solution or a polyimide solution. When a polyimide solution is used, the dehydration ring-closure reaction proceeds by heat treatment in step F to form a polyimide film. When a polyimide solution is used, a thin film of polyimide is formed by volatilizing the solvent in step C.

The aforementioned polyamic acid solution is obtained by reacting diamines and tetracarboxylic dianhydrides in a solvent.

As the aforementioned tetracarboxylic acids, aromatic tetracarboxylic acids (including acid anhydrides thereof), aliphatic tetracarboxylic acids (including acid anhydrides thereof), and alicyclic tetracarboxylic acids (including acid anhydrides thereof) commonly used in the synthesis of polyimide can be used ). Among them, aromatic tetracarboxylic anhydrides and alicyclic tetracarboxylic anhydrides are preferred. Tetracarboxylic acids may be used alone or in combination of two or more.

Examples of alicyclic tetracarboxylic acids include cyclobutanetetracarboxylic acid, 1,2,4,5-cyclohexanetetracarboxylic acid, 3,3',4,4'-bicyclohexanetetracarboxylic acid Alicyclic tetracarboxylic acids such as acids, and acid anhydrides thereof. Among these, there are dianhydrides with two anhydride structures (for example: cyclobutane tetracarboxylic dianhydride, 1,2,4,5-cyclohexane tetracarboxylic dianhydride, 3,3',4, 4'-bicyclohexanetetracarboxylic dianhydride, etc.) are preferred. In addition, alicyclic tetracarboxylic acids may be used alone or in combination of two or more. When importance is attached to transparency, the alicyclic tetracarboxylic acid is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more of all tetracarboxylic acids, for example.

Although it does not specifically limit as aromatic tetracarboxylic acid, For example, pyromellitic dianhydride, 3,3',4,4'-biphenyltetracarboxylic dianhydride, 4,4'-oxydi Phthalic dianhydride, 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 3,3',4,4'-diphenyl tetracarboxylic dianhydride, 2,2- Bis[4-(3,4-dicarboxyphenoxy)phenyl]propionic anhydride, etc. When emphasis is placed on heat resistance, the content of the aromatic tetracarboxylic acids is preferably 80% by mass or more, more preferably 90% by mass or more, and even more preferably 95% by mass or more, for example, of all tetracarboxylic acids.

There are no particular limitations on the above-mentioned diamines, and aromatic diamines, aliphatic diamines, etc., which are generally used in the synthesis of polyimide, can be used. From the viewpoint of heat resistance, aromatic diamines are preferred, and among the aromatic diamines, aromatic diamines having a benzoxazole structure are more preferred. When an aromatic diamine having a benzoxazole structure is used, it becomes possible to express high elastic modulus, low thermal shrinkage, and low linear expansion coefficient while expressing high heat resistance. Diamines may be used alone or in combination of two or more.

It does not specifically limit as aromatic diamines which have a benzoxazole structure, For example, 5-amino-2-(p-aminophenyl)benzoxazole, 6-amino-2-( p-aminophenyl)benzoxazole, 5-amino-2-(m-aminophenyl)benzoxazole, 6-amino-2-(m-aminophenyl)benzoxazole, 2 ,2'-p-phenylene bis(5-aminobenzoxazole), 2,2'-p-phenylene bis(6-aminobenzoxazole), 1-(5-aminobenzoxazole) oxazolo)-4-(6-aminobenzoxazolo)benzene, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:5,4- d'] Bisoxazole, 2,6-(4,4'-diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole, 2,6-(3 ,4'-Diaminodiphenyl)benzo[1,2-d:5,4-d']bisoxazole, 2,6-(3,4'-diaminodiphenyl)benzo [1,2-d:4,5-d']bisoxazole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:5,4-d' ] Bisoxazole, 2,6-(3,3'-diaminodiphenyl)benzo[1,2-d:4,5-d']bisoxazole, etc.

Examples of aromatic diamines other than the aromatic diamines having the above-mentioned benzoxazole structure include 2,2'-dimethyl-4,4'-diaminobiphenyl, 1,4 -Bis[2-(4-aminophenyl)-2-propyl]benzene (bisaniline), 1,4-bis(4-amino-2-trifluoromethylphenoxy)benzene, 2, 2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl, 4,4'-bis(4-aminophenoxy)biphenyl, 4,4'-bis(3-amine phenoxy) biphenyl, bis[4-(3-aminophenoxy)phenyl]ketone, bis[4-(3-aminophenoxy)phenyl]sulfide, bis[4-( 3-Aminophenoxy)phenyl] bismuth, 2,2-bis[4-(3-aminophenoxy)phenyl]propane, 2,2-bis[4-(3-aminophenoxy) base)phenyl]-1,1,1,3,3,3-hexafluoropropane, m-phenylenediamine, o-phenylenediamine, p-phenylenediamine, m-aminobenzylamine, p-aminobenzyl amine, 3,3'-diaminodiphenyl ether, 3,4'-diaminodiphenyl ether, 4,4'-diaminodiphenyl ether, 3,3'-diaminodiphenyl Sulfide, 3,3'-diaminodiphenylene, 3,4'-diaminodiphenylene, 4,4'-diaminodiphenylene, 3,3'- Diaminodiphenylene, 3,4'-diaminodiphenylene, 4,4'-diaminodiphenylene, 3,3'-diaminobenzophenone, 3,4'-diaminobenzophenone Aminobenzophenone, 4,4'-diaminobenzophenone, 3,3'-diaminodiphenylmethane, 3,4'-diaminodiphenylmethane, 4,4' -Diaminodiphenylmethane, bis[4-(4-aminophenoxy)phenyl]methane, 1,1-bis[4-(4-aminophenoxy)phenyl]ethane, 1,2-bis[4-(4-aminophenoxy)phenyl]ethane, 1,1-bis[4-(4-aminophenoxy)phenyl]propane, 1,2-bis [4-(4-Aminophenoxy)phenyl]propane, 1,3-bis[4-(4-aminophenoxy)phenyl]propane, 2,2-bis[4-(4- Aminophenoxy)phenyl]propane, 1,1-bis[4-(4-aminophenoxy)phenyl]butane, 1,3-bis[4-(4-aminophenoxy) ) phenyl]butane, 1,4-bis[4-(4-aminophenoxy)phenyl]butane, 2,2-bis[4-(4-aminophenoxy)phenyl] Butane, 2,3-bis[4-(4-aminophenoxy)phenyl]butane, 2-[4-(4-aminophenoxy)phenyl]-2-[4-( 4-Aminophenoxy)-3-methylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)-3-methylphenyl]propane, 2-[4- (4-Aminophenoxy)phenyl]-2-[4-(4-aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4 -Aminophenoxy)-3,5-dimethylphenyl]propane, 2,2-bis[4-(4-aminophenoxy)phenyl]-1,1,1,3,3 , 3-hexafluoropropane, 1,4-bis(3-aminophenoxy)benzene, 1,3-bis(3-aminophenoxy)benzene, 1,4-bis(4-aminophenoxy)benzene, 4,4'-bis(4-aminophenoxy)biphenyl, bis[4-(4-aminophenoxy)phenyl]ketone, bis[4-(4-aminophenoxy)phenyl]sulfide, bis[4-(4-aminophenoxy) Phenyl] sulfite, bis[4-(4-aminophenoxy)phenyl]sine, bis[4-(3-aminophenoxy)phenyl]ether, bis[4-(4-amine) phenoxy)phenyl] ether, 1,3-bis[4-(4-aminophenoxy)benzyl]benzene, 1,3-bis[4-(3-aminophenoxy) ) benzyl]benzene, 1,4-bis[4-(3-aminophenoxy)benzyl]benzene, 4,4'-bis[(3-aminophenoxy)benzyl Acyl]benzene, 1,1-bis[4-(3-aminophenoxy)phenyl]propane, 1,3-bis[4-(3-aminophenoxy)phenyl]propane, 3 ,4'-Diaminodiphenyl sulfide, 2,2-bis[3-(3-aminophenoxy)phenyl]-1,1,1,3,3,3-hexafluoropropane, bis[4-(3-aminophenoxy)phenyl]methane, 1,1-bis[4-(3-aminophenoxy)phenyl]ethane, 1,2-bis[4-( 3-Aminophenoxy)phenyl]ethane, bis[4-(3-aminophenoxy)phenyl]thylene, 4,4'-bis[3-(4-aminophenoxy) ) benzyl] diphenyl ether, 4,4'-bis[3-(3-aminophenoxy)benzyl]diphenyl ether, 4,4'-bis[4-(4-amine) base-α,α-dimethylbenzyl)phenoxy]benzophenone, 4,4'-bis[4-(4-amino-α,α-dimethylbenzyl)phenoxy base] diphenylene, bis[4-{4-(4-aminophenoxy)phenoxy}phenyl]sene, 1,4-bis[4-(4-aminophenoxy)phenoxy base-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-aminophenoxy)phenoxy-α,α-dimethylbenzyl]benzene, 1 ,3-bis[4-(4-amino-6-trifluoromethylphenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino) -6-Fluorophenoxy)-α,α-dimethylbenzyl]benzene, 1,3-bis[4-(4-amino-6-methylphenoxy)-α,α-di methylbenzyl]benzene, 1,3-bis[4-(4-amino-6-cyanophenoxy)-α,α-dimethylbenzyl]benzene, 3,3'-bis Amino-4,4'-diphenoxybenzophenone, 4,4'-diamino-5,5'-diphenoxybenzophenone, 3,4'-diamino-4 ,5'-diphenoxybenzophenone, 3,3'-diamino-4-phenoxybenzophenone, 4,4'-diamino-5-phenoxybenzophenone , 3,4'-diamino-4-phenoxybenzophenone, 3,4'-diamino-5'-phenoxybenzophenone, 3,3'-diamino-4 ,4'-diphenyloxybenzophenone, 4,4'-diamino-5,5'-dibenzyloxybenzophenone, 3,4'-diphenyloxybenzophenone Amino-4,5'-diphenyloxybenzophenone, 3,3'-diamino-4-biphenoxybenzophenone, 4,4'-diamino-5-biphenone Phenoxybenzophenone, 3,4'-Diamino-4-biphenoxybenzophenone, 3,4'-Diamino-5'-biphenoxybenzophenone, 1 ,3-bis(3-amino-4-phenoxybenzyl)benzene, 1,4-bis(3-amino-4-phenoxybenzyl)benzene, 1,3-bis (4-Amino-5-phenoxybenzyl)benzene, 1,4-bis(4-amino-5-phenoxybenzyl)benzene, 1,3-bis(3-amine Benzyl-4-biphenoxybenzyl)benzene, 1,4-bis(3-amino-4-biphenoxybenzyl)benzene, 1,3-bis(4-amino- 5-Biphenoxybenzyl)benzene, 1,4-bis(4-amino-5-biphenoxybenzyl)benzene, 2,6-bis[4-(4-amino) -α,α-Dimethylbenzyl)phenoxy]benzonitrile, and some or all of the hydrogen atoms on the aromatic ring of the aforementioned aromatic diamines are replaced by halogen atoms, alkyl groups having 1 to 3 carbon atoms, or An alkoxy group, a cyano group, a halogenated alkyl group having 1 to 3 carbon atoms or an aromatic diamine substituted with an alkoxy group in which a part or all of the hydrogen atoms of an alkyl group or an alkoxy group are substituted with a halogen atom.

Examples of the aforementioned aliphatic diamines include 1,2-diaminoethane, 1,4-diaminobutane, 1,5-diaminopentane, and 1,6-diaminohexane alkane, 1,8-diaminooctane, etc. Moreover, as said aliphatic diamines, 1, 4- diamino cyclohexane, 4, 4'- methylene bis (2, 6- dimethyl cyclohexylamine), etc. are mentioned, for example. The total amount of diamines (aliphatic diamines) other than aromatic diamines is preferably 20% by mass or less of all diamines, more preferably 10% by mass or less, and still more preferably 5% by mass or less. In other words, the aromatic diamines are preferably 80% by mass or more of all diamines, more preferably 90% by mass or more, and even more preferably 95% by mass or more.

As the aforementioned solvent, the same ones as those described in the item of the first resin composition solution can be used.

[Film before cutting] The film before cutting of this embodiment has: the central part composed of the first resin composition, and It is formed continuously from the central portion at both ends of the central portion, The both ends are made of a second resin composition different from the first resin composition, The tear strength of the both end portions is greater than the tear strength of the central portion.

The said pre-cutting film can be obtained by the said process A - the said process C of the resin film manufacturing method of this embodiment. Here, the "first resin composition" refers to the composition (sheet-like object) obtained by drying the first resin composition solution in the above-mentioned step C, and the "second resin composition" refers to the above-mentioned step C. The composition (flake) after drying of the second resin composition solution.

The tear strength of the central portion is preferably within the range of 0.1 to 15 N/mm, more preferably within the range of 1 to 10 N/mm, in the following measurement method.

The tear strength at both ends is preferably within the range of 0.5 to 30 N/mm, and more preferably within the range of 1 to 20 N/mm, in the following measurement method. In addition, the tear strength of the both ends is preferably more than 1 time and 10 times or less of the tear strength of the center part, and more preferably more than 1.1 times and 5 times or less.

<Measuring method of tear strength> According to the trouser tearing method described in JIS K7128-1, the test speed was set to 200 mm/min, and the average value of the remaining 50 mm excluding 20 mm at the beginning of tearing and 5 mm before the end of tearing was set as the tear strength. [Tear strength (N/mm)]=[Tear strength of test piece (N)]/[Thickness of test piece (d)]

The width of the both ends (width of each end) is not particularly limited as long as it can be held by a conventionally known tenter-type conveying device, but is generally 5 mm or more, more preferably 10 mm or more. The upper limit of the width is not particularly limited. For example, the total of both ends may be equal to or less than 50% of the full width of the film, more preferably 30% or less, and even more preferably 10% or less. The width of the both ends (width of each end) is not particularly limited as long as it is a width that can be sandwiched by a conventionally known tenter-type conveying device. For example, the sum of the widths of both ends is the total width of the film. 0.1% or more, more preferably 0.5% or more, still more preferably 1% or more. The upper limit of the width is not particularly limited. For example, the sum of the widths of both ends may be 50% or less of the full width of the film, more preferably 30% or less, and even more preferably 10% or less.

The pre-cutting film of the present embodiment has been described above. [Example]

Hereinafter, the present invention will be described in detail using examples, but the present invention is not limited to the following examples as long as the gist of the present invention is not exceeded.

[Synthesis Example 1 (Preparation of Polyamic Acid Solution A)] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring bar, 1470.8 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic dianhydride ( CBDA), 775.6 parts by mass of 4,4'-oxydiphthalic acid (ODPA), 3202.4 parts by mass of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB), 5448.8 parts by mass of silica sol were dispersed in dimethylacetamide (DMAc-ST manufactured by Nissan Chemical Co., Ltd.), and 21795 parts by mass of N,N-dimethylacetamide were dissolved. The mixture was stirred at room temperature for 24 hours to obtain a polyamic acid solution A having a reduced viscosity of 4.5 dl/g with a solid content of 17.2 parts by mass.

[Synthesis Example 2 (Preparation of Polyimide Solution B)] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring bar, 551 parts by mass of N,N-dimethylacetamide (DMAC) and 64.1 parts by mass were put into the reaction vessel under a nitrogen atmosphere. 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB) and stirring to dissolve TFMB in DMAC. Next, 44.4 parts by mass of 4,4'-(2,2-hexafluoroisopropylidene)diphthalic dianhydride (6FDA), 4,4'-(2,2-hexafluoroisopropylidene)diphthalic dianhydride (6FDA), and 29.4 parts by mass of biphenyl tetracarboxylic dianhydride (BPDA), and continued stirring for 6 hours while adjusting the temperature to be in the temperature range of 20 to 40° C. to carry out the polymerization reaction to obtain a viscous polyamic acid solution. Next, after adding 410 parts by mass of DMAC to the obtained polyamic acid solution and diluting it, 25.83 parts by mass of isoquinoline was added as an imidization accelerator, and the polyamic acid solution was kept at 30 to 40° C. while stirring. In this temperature range, 122.5 parts by mass of acetic anhydride was added as an imidizing agent while slowly dropping it for about 10 minutes, and thereafter, the liquid temperature was further maintained at 30 to 40° C. and stirring was continued for 12 hours to carry out chemical analysis. The imidization reaction is carried out to obtain a polyimide solution. Next, 1,000 parts by mass of the obtained polyimide solution containing the imidization agent and the imidization accelerator was transferred to a reaction vessel equipped with a stirring device and a stirring blade, and kept at 15 while stirring at a speed of 120 rpm. At a temperature of -25°C, 1500 parts by mass of methanol was added dropwise thereto at a rate of 10 g/min. When about 800 parts by mass of methanol was charged, the turbidity of the polyimide solution was confirmed, and the precipitation of powdery polyimide was confirmed. The total amount of 1500 parts by mass of methanol was continued to be added to complete the precipitation of the polyimide. Next, the contents of the reaction container were filtered by an air suction filter, and further washed and filtered using 1000 parts by mass of methanol. After that, 50 parts by mass of the filtered polyimide powder was dried at 50° C. for 24 hours using a dryer equipped with a local exhaust device, and further dried at 260° C. for 2 hours to remove residual volatile components to obtain a polymer Imide powder. The reduced viscosity of the obtained polyimide powder was 2.1 dl/g. Next, 42 parts by mass of the obtained polyimide powder was dissolved in 168 parts by mass of DMAC to obtain a polyimide solution B having a solid content of 20 parts by mass.

[Synthesis Example 3 (Preparation of Polyimide Solution C)] 124.15 parts by mass of 4,4'-diaminodiphenylene (4,4'-DDS) was added to a reaction vessel equipped with a nitrogen gas introduction tube, a Dean-Stark apparatus, a reflux tube, a thermometer, and a stirring bar while introducing nitrogen gas. ), 124.15 parts by mass of 3,3'-diaminodiphenylene (3,3'-DDS), and 750 parts by mass of γ-butyrolactone (GBL). Next, 248.18 parts by mass of 4,4'-oxydiphthalic dianhydride (ODPA), 58.8 parts by mass of biphenyltetracarboxylic dianhydride, 335 parts by mass of GBL, and 390 parts by mass of After toluene, the temperature was raised to an internal temperature of 160°C, and the mixture was heated to reflux at 160°C for 1 hour to carry out imidization. After the imidization was completed, the temperature was raised to 180°C, and the reaction was continued while drawing out toluene. After 12 hours of reaction, the oil bath was released, the temperature was returned to room temperature, 1149 parts by mass of GBL was added so that the solid content was 20 parts by mass, and a polyimide solution C with a reduced viscosity of 0.6 dl/g was obtained.

[Synthesis Example 4 (Preparation of Polyamic Acid Solution D)] 384.38 parts by mass of norbornane-2-spiro-α-cyclopentanone- α'-spiro-2''-norbornane-5,5'',6,6''-tetracarboxylic dianhydride (CpODA), 348.45 parts by mass of 9,9-bis(4-aminophenyl) ) (BAFL), 36.00 parts by mass of triethylamine, 1465 parts by mass of N-methyl-2-pyrrolidone (NMP), 1465 parts by mass of γ-butyrolactone (GBL), 360 parts by mass of toluene After that, the temperature was raised to an internal temperature of 180°C, and heating imidization was performed at 180°C for 3 hours while distilling off toluene to obtain a polyimide solution. Next, 2500 parts by mass of the obtained polyimide solution was transferred to a reaction vessel equipped with a stirring device and a stirring blade, and kept at a temperature of 15 to 25° C. while stirring at a speed of 120 rpm, and dripped at a rate of 10 g/min. Add 50,000 parts by mass of acetone. When about 2,500 parts by mass was charged, the turbidity of the polyimide solution was confirmed, and the precipitation of powdery polyimide was confirmed. The remaining 2500 parts by mass of acetone was continuously added to complete the precipitation of the polyimide. Next, the contents of the reaction vessel were filtered by an air suction filter, and further washed and filtered using 2000 parts by mass of methanol. After that, 300 parts by mass of the filtered polyimide powder was dried at 50° C. for 24 hours using a dryer equipped with a local exhaust device, and further dried at 260° C. for 2 hours to remove residual volatile components to obtain a polymer Imide powder. The reduced viscosity of the obtained polyimide powder was 0.7 dl/g. Next, 42 parts by mass of the obtained polyimide powder was dissolved in 168 parts by mass of NMP to obtain a polyimide solution D having a reduced viscosity of 0.7 dl/g with a solid content of 20 parts by mass.

[Synthesis Example 5 (Preparation of Polyamic Acid Solution E)] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer and a stirring bar, 196.1 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic dianhydride (1,2,3,4-cyclobutanetetracarboxylic dianhydride ( CBDA), 227.3 parts by mass of 4-amino-N-(4-aminophenyl)benzamide (DABAN), and 1694 parts by mass of N,N-dimethylacetamide and dissolved , and stirred at room temperature for 24 hours to obtain a polyamic acid solution E with a reduced viscosity of 4.5 dl/g having a solid content of 20 parts by mass.

[Synthesis Example 6 (Preparation of Polyamic Acid Solution F)] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer and a stirring bar, 196.1 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic dianhydride (1,2,3,4-cyclobutanetetracarboxylic dianhydride ( CBDA), 160.1 parts by mass of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB), 113.6 parts by mass of 4-amino-N-(4-amino Phenyl)benzamide (DABAN) and 1879 parts by mass of N,N-dimethylacetamide were dissolved and then stirred at room temperature for 24 hours to obtain a reduced viscosity with a solid content of 20 parts by mass 4.5 dl/g of polyamic acid solution F.

[Synthesis Example 7 (Preparation of Polyamic Acid Solution G)] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring bar, 2,002.4 parts by mass of 4,4'-diaminodiphenyl ether was charged. Next, after adding 16,647 parts by mass of N,N-dimethylacetamide and completely dissolving it, 2,159.4 parts by mass of pyromellitic dianhydride was added, and the mixture was stirred at a reaction temperature of 25° C. for 15 hours to obtain a solid content of 20 Mass parts of brown and viscous polyamide solution G with a reduced viscosity of 3.5 dl/g.

[Synthesis Example 8 (Preparation of Polyamide Imide Solution H] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring bar, 153.7 parts by mass of trimellitic acid, 256.4 parts by mass of O-lysine diisocyanate, 3,3',4,4'-diisocyanate were added. 29.4 parts by mass of pyromellitic dianhydride, 32.2 parts by mass of 3,3',4,4'-benzophenone tetracarboxylic dianhydride, 1 part by mass of triethylenediamine, and N-methyl-2- The temperature of 1,671 parts by mass of pyrrolidone was raised to 130° C. over 1 hour while stirring, and was further reacted at 130° C. for 5 hours to obtain a polyimide-based resin solution having a logarithmic viscosity of 1.6 dl/g. Snowtex (DMAC-ST, manufactured by Nissan Chemical Industries, Ltd.) obtained by dispersing colloidal silicon oxide in dimethylacetamide was added so that the silicon oxide became 0.5 parts by mass, and a solution H was obtained.

[Synthesis Example 9 (Preparation of Polyamic Acid Solution J] After nitrogen substitution was carried out in a reaction vessel equipped with a nitrogen introduction tube, a thermometer, and a stirring bar, 980.6 parts by mass of 1,2,3,4-cyclobutanetetracarboxylic dianhydride ( CBDA), 1029 parts by mass of 3,3',4,4'-biphenyltetracarboxylic dianhydride (BPDA), 465.3 parts by mass of 4,4'-oxydiphthalic acid (ODPA), 3202.4 mass parts parts of 2,2'-bis(trifluoromethyl)-4,4'-diaminobiphenyl (TFMB) and 32,171 parts by mass of N,N-dimethylacetamide were dissolved in The polymerization was carried out by stirring at room temperature for 24 hours to obtain a polyamic acid solution J with a reduced viscosity of 3.50 dl/g.

[Reduced viscosity] The reduction viscosity (dL/g) of the prepared polyimide solutions A, D to F, and polyimide solutions B and C was obtained by dissolving 0.02 g of each sample in 10 mL of a mixed solvent (phenol/tetrachloroethane=60 /40 (mass ratio)), measured at 30°C using an Ubbelohde viscometer.

(Example 1) A polyamic acid solution A (synthesis example 1) and a polyamic acid solution G (synthesis example 7) were prepared. A PET film (A4100, manufactured by Toyobo Co., Ltd.) was applied to the support by adjusting the clearance so that the final film thickness would be 25 μm using the notch wheel coater shown in FIGS. At the same time as the width of the central portion was 500 mm, the polyamide solution G was applied to the both ends of the solution G with a width of 50 mm, respectively. At this time, the width of the side plate is 10mm. Next, it was dried at 100 to 110° C. for 10 minutes to form a polyamide film, and after drying, it was wound around a 6-inch ABS core together with the PET film to obtain a polyamide film roll. The polyamic acid film and the PET film were rolled out from the obtained polyamic acid film roll, and peeled from the PET film to obtain a self-supporting polyamic acid film to obtain a polyamic acid film. The obtained polyamide film was passed through a pin tenter having a needle plate arranged so that the needle interval was constant when the needle plate was arranged, and the end of the film was clamped by inserting the needle, so that the film was not broken. Adjust the needle plate interval so as not to cause unnecessary sagging, and convey the needle plate interval so that the final needle plate interval is 520 mm. Heating was performed under the conditions of 3 minutes at 350°C as the 3rd stage and 3 minutes at 350°C as the 4th stage, and the imidization reaction was carried out. After that, it was cooled to room temperature for 2 minutes, and then the film formed with the polyimide solution G was torn at the end to make only the center part, to obtain a polyimide film with a thickness of 25 μm and a width of 480 mm.

(Example 2) A polyamic acid solution A (synthesis example 1) and a polyamic acid solution G (synthesis example 7) were prepared. Using the notch wheel coater shown in Figure 7 and Figure 8, the polyamide solution G was coated on the mirror-polished stainless steel belt at both ends, and then the T-die was used to adjust the clearance so that the final film thickness was 25 μm. And the polyamic acid solution A was apply|coated to the center part. At this time, it apply|coated so that the width|variety of a center part might become 1000 mm, and each both ends would become a width of 50 mm. Next, it dried at 100-110 degreeC for 10 minutes, and after drying, it peeled from a support body, and obtained the self-supporting polyamic acid film. The obtained film before cutting is passed through a pin tenter having a needle plate that arranges needles so that the needle interval is constant when the needle plates are arranged, and the ends of the film are sandwiched by inserting the needles so that the film is not broken and Adjust the needle plate interval so that unnecessary sagging does not occur, and convey the final needle plate interval to 1000 mm, at 200°C for 3 minutes as the first step, at 250°C for 3 minutes as the second step, and at 300°C Heating was performed under the conditions that the following 3 minutes were set as the third stage and 3 minutes at 350° C. as the fourth stage, and the imidization reaction was carried out. After that, it was cooled to room temperature for 2 minutes, and then the film formed by the polyamide solution G was torn at the ends to make only the central portion, and was continuously wound into a roll on a 3-inch core made of ABS resin to obtain Polyimide film with a thickness of 25μm, a width of 980mm and a length of 500m.

(Example 3) A polyamic acid solution A (synthesis example 1) and a polyamic acid solution G (synthesis example 7) were prepared. The T-die shown in Fig. 9 and Fig. 10 was used to coat the polyamide solution G on the mirror-polished stainless steel belt at both ends, and the T-die was used to adjust the clearance so that the final film thickness was 25 μm. The amine acid solution A was applied to the central portion. At this time, it apply|coated so that the width|variety of a center part might become 1000 mm, and each both ends would become a width of 50 mm. Next, it dried at 100-110 degreeC for 10 minutes, and after drying, it peeled from a support body, and obtained the self-supporting polyamic acid film. The obtained film before cutting is passed through a pin tenter having a needle plate that arranges needles so that the needle interval is constant when the needle plates are arranged, and the ends of the film are sandwiched by inserting the needles so that the film is not broken and Adjust the needle plate interval so as not to cause unnecessary sagging, convey the final needle plate interval of 520 mm, at 200°C for 3 minutes as the first step, at 250°C for 3 minutes as the second step, and at 300°C Heating was performed under the conditions that the following 3 minutes were set as the third stage and 3 minutes at 350° C. as the fourth stage, and the imidization reaction was carried out. After that, it was cooled to room temperature for 2 minutes, and then the film formed by the polyamide solution G was torn at the ends to make only the central portion, and was continuously wound into a roll on a 3-inch core made of ABS resin to obtain Polyimide film with a thickness of 25μm, a width of 980mm and a length of 500m.

(Example 4) A polyimide solution B (synthesis example 2) and a polyimide solution G (synthesis example 7) were prepared. A polyimide film having a thickness of 12.5 μm and a width of 480 mm was obtained in the same manner as in Example 1, except that the gap was adjusted so that the final film thickness was 12.5 μm, and the polyimide solution B was applied instead of the polyimide solution A. .

(Example 5) A polyimide solution C (synthesis example 3) and a polyimide imide solution H (synthesis example 8) were prepared. In addition to adjusting the clearance so that the final film thickness is 12.5 μm, the polyimide solution C is applied instead of the polyimide solution A, and the polyimide solution H is used instead of the polyimide solution G (synthesis Except Example 7), it carried out similarly to Example 1, and obtained the polyimide film of thickness 12.5 micrometers and width 480mm.

(Example 6) A polyamic acid solution D (synthesis example 4) and a polyamic acid solution G (synthesis example 7) were prepared. A polyimide film having a thickness of 25 μm and a width of 480 mm was obtained in the same manner as in Example 1, except that the gap was adjusted so that the final film thickness was 25 μm, and the polyimide solution D was applied instead of the polyimide solution A. .

(Example 7) A polyamic acid solution E (synthesis example 5) and a polyamic acid solution G (synthesis example 7) were prepared. A polyimide film having a thickness of 25 μm and a width of 480 mm was obtained in the same manner as in Example 1, except that the gap was adjusted so that the final film thickness was 25 μm, and the polyimide solution E was applied instead of the polyimide solution A. .

(Example 8) A polyamic acid solution F (synthesis example 6) and a polyamic acid solution G (synthesis example 7) were prepared. A polyimide film having a thickness of 25 μm and a width of 480 mm was obtained in the same manner as in Example 1, except that the gap was adjusted so that the final film thickness was 25 μm, and the polyimide solution F was applied instead of the polyimide solution A. .

(Example 9) A polyamic acid solution J (synthesis example 9) and a polyamic acid solution G (synthesis example 7) were prepared. A polyimide film having a thickness of 25 μm and a width of 480 mm was obtained in the same manner as in Example 1, except that the gap was adjusted so that the final film thickness was 25 μm, and the polyimide solution J was applied instead of the polyimide solution A.

(Comparative Example 1) Using a notch wheel coater, the PET film (A4100, manufactured by Toyobo Co., Ltd.) of the support was coated with the polyamide solution A (synthesis example) with the clearance adjusted so as to have a width of 600 mm and a final film thickness of 25 μm. 1). Next, it dried at 100-110 degreeC for 10 minutes, and after drying, it peeled from a support body, and obtained the self-supporting polyamic acid film. The obtained polyamide film was passed through a pin tenter having a needle plate arranged so that the needle interval was constant when the needle plate was arranged, and the end of the film was clamped by inserting the needle, so that the film was not broken. Adjust the needle plate interval so as not to cause unnecessary sagging, and convey the needle plate interval so that the final needle plate interval is 520 mm. Heating was performed under the conditions of 3 minutes at 350°C as the 3rd stage and 3 minutes at 350°C as the 4th stage, and the imidization reaction was carried out. After that, it was cooled to room temperature for 2 minutes, and when it was removed from the needle plate, it was broken from the hole portion through which the needle passed, and a film could not be obtained.

(Comparative Examples 2 to 6) Except using the resins of Synthesis Examples 2 to 6 in place of Synthesis Example 1 used in Comparative Example 1, the same procedure as in Comparative Example 1 was conducted to try to produce the films of Comparative Examples 2 to 6, but all of them were removed from the needle plate. , it will rupture from the hole portion through which the needle passes and the film will not be obtained.

<Thickness measurement of thin films> The thickness of the thin film was measured using a micrometer (Militron 1245D manufactured by Feinprüf).

＜Tear strength＞ The tear strength of the central portion and the tear strength of both end portions of the films obtained in the Examples and Comparative Examples before cutting were determined. Specifically, according to the trousers tearing method described in JIS K7128-1, the test speed was set to 200 mm/min, and the average value of the remaining 50 mm excluding the 20 mm at the beginning of the tear and the 5 mm before the end of the tear was regarded as the tear crack strength. The results are shown in Table 1 and Table 2. [Tear strength (N/mm)]=[Tear stress of test piece (N)]/[Thickness of test piece (d)]

The tear strength obtained here (the tear strength described in Table 1 and Table 2) is the tear strength of the polyimide film (resin film) after step G, but only the polyimide film after step G In the amine film, the tear strength of the part formed from the second resin composition solution is higher than the tear strength of the part formed from the first resin composition solution. In the film before breaking, the tear strength of the portion formed from the second resin composition solution is also larger than the tear strength of the portion formed from the first resin composition solution. Moreover, the tear strength of the center part of the film before cutting after step C of Example 8 and before step F was measured by the same measurement method as above, and it was 1.8 N/mm. It is also obvious from this that as long as in the polyimide film after step G, the tear strength of the part formed by the second resin composition solution is higher than the tear strength of the part formed by the first resin composition solution If the tear strength is larger, the tear strength of the portion formed from the second resin composition solution in the film before cutting after step C and before step F also becomes higher than that of the portion formed from the first resin composition solution. Parts have greater tear strength.

[Table 1] Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Implementation form 1st form 2nd form 3rd form 1st form 1st form 1st form 1st form 1st form 1st form coating conditions End coated resin Synthesis Example 7 Synthesis Example 7 Synthesis Example 7 Synthesis Example 7 Synthesis Example 8 Synthesis Example 7 Synthesis Example 7 Synthesis Example 7 Synthesis Example 7 End coating width (one side) mm 50 50 50 50 50 50 50 50 50 Resin coating on the center Synthesis Example 1 Synthesis Example 1 Synthesis Example 1 Synthesis Example 2 Synthesis Example 3 Synthesis Example 4 Synthesis Example 5 Synthesis Example 6 Synthesis Example 9 Central coating width mm 500 1000 1000 1000 500 500 500 500 500 Initial drying conditions drying temperature °C 100-110 100-110 100-110 100-110 100-110 100-110 100-110 100-110 100-110 drying time Minute 10 10 10 10 10 10 10 10 10 Heat treatment conditions heat treatment temperature °C 200 200 200 200 200 200 200 200 200 250 250 250 250 250 250 250 250 250 300 300 300 300 300 300 300 300 300 350 350 350 350 300 350 350 350 350 Heat treatment time Minute 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 The state of the film※ ○ ○ ○ ○ ○ ○ ○ ○ ○ thickness both ends μm 20 25 25 12.5 17 20 20 20 20 Central Department 25 25 25 12.5 12.5 25 25 25 25 tear strength both ends N/mm 4.5 4.5 4.5 4.5 3 4.5 4.5 4.5 4.5 Central Department 1.6 1.6 1.6 1.7 1.7 1.2 1.5 1.5 1.5 tear stress both ends N 0.090 0.113 0.113 0.056 0.051 0.090 0.090 0.090 0.090 Central Department 0.040 0.040 0.040 0.021 0.021 0.030 0.038 0.038 0.038 ※No cracking and deformation: ○ Partially cracked during heat treatment: △ Cracked during heat treatment, no film obtained: ×

[Table 2] Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 Implementation form - - - - - - coating conditions End coated resin - - - - - - End coating width (one side) mm - - - - - - Resin coating on the center Synthesis Example 1 Synthesis Example 2 Synthesis Example 3 Synthesis Example 4 Synthesis Example 5 Synthesis Example 6 Central coating width mm 600 600 600 600 600 600 Initial drying conditions drying temperature °C 100-110 100-110 100-110 100-110 100-110 100-110 drying time Minute 10 10 10 10 10 10 Heat treatment conditions heat treatment temperature °C 200 200 200 200 200 200 250 250 250 250 250 250 300 300 300 300 300 300 350 350 300 350 350 350 Heat treatment time Minute 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 3-3-3-3 The state of the film※ × △ △ × × × thickness both ends μm - - - - - - Central Department 25 12.5 12.5 25 25 25 tear strength both ends N/mm - - - - - - Central Department 1.6 1.7 1.7 1.2 1.5 1.5 tear stress both ends N - - - - - - Central Department 0.040 0.021 0.021 0.030 0.038 0.038 ※No cracking or deformation: ○ Partially cracked during heat treatment: △ Cracked during heat treatment, no film obtained: ×

In the polyimide films of Examples 1 to 9, the tear strength of the part formed from the second resin composition solution was higher than the tear strength of the part formed from the first resin composition solution, so after the heat treatment No cracking and deformation. On the other hand, since the films before cutting in Comparative Examples 1 to 6 were formed of a single resin composition solution having a low tear strength, they were damaged from the holes through which the needles passed, and films could not be obtained.

10,30,40,50: Coating device 12: Back roller 14: Cutaway wheel roller 16 (16a, 16b, 16c): coating liquid storage part 18 (18a, 18b, 18c, 18d): side panels 20: Backplane 22: Gap 60: Support body 62 (62a, 62b, 62c): coating liquid 64 (64a, 64b, 64c): coating film

Fig. 1 is a side sectional view for explaining a method of applying a resin composition solution according to the first embodiment. FIG. 2 is a plan view of FIG. 1 . FIG. 3 is a partially enlarged plan view of the vicinity of the side plate 18b shown in FIG. 2 . FIG. 4 is a cross-sectional view showing a state where each coating film is connected only by the side surface. FIG. 5 is a cross-sectional view showing a state where the coating film 64a and the coating film 64c are slightly overlapped on the coating film 64b. FIG. 6 is a cross-sectional view showing a state where the coating film 64b is slightly overlapped on the coating film 64a and the coating film 64c. Fig. 7 is a side sectional view for explaining the coating method of the resin composition solution according to the second embodiment. FIG. 8 is a plan view of FIG. 7 . Fig. 9 is a side sectional view for explaining the coating method of the resin composition solution according to the third embodiment. FIG. 10 is a plan view of FIG. 9 . 11 is a cross-sectional view showing a state where the end portion of the coating film 64a is slightly overlapped on the coating film 64b, and the end portion of the coating film 64b is slightly overlapped on the coating film 64c. Fig. 12 is a side sectional view for explaining the coating method of the resin composition solution according to the fourth embodiment. FIG. 13 is a plan view of FIG. 12 .

10: Coating device

14: Cutaway wheel roller

16a, 16b, 16c: coating liquid reservoir

18a, 18b, 18c, 18d: side panels

20: Backplane

60: Support body

62a, 62b, 62c: coating liquid

64a, 64b, 64c: Coated film

Claims (5)

A method for manufacturing a resin film, characterized in that it has: Step A, which is to coat the first resin composition solution on the central part of the support, Step B, which is to coat the second resin composition solution on both ends adjacent to the central portion, Step C, which is to dry the first resin composition solution and the second resin composition solution to obtain a film before cutting, Step D, which is to peel off the pre-cut film from the support, Step E, after the step D, the two ends of the film before being cut are clamped by a tenter-type conveying device, Step F of conveying the pre-cut film in a state of sandwiching both ends of the pre-cut film, and Step G, after the step F, removing the portion formed by the second resin composition solution from the pre-cutting film to obtain a resin film; After the step C and before the step F, the tear strength of the portion of the pre-cutting film formed from the second resin composition solution is higher than the tear strength of the portion formed from the first resin composition solution. big. The method for producing a resin film according to claim 1, wherein the step E is a step of sandwiching both ends of the film before cutting with needles of a pin tenter-type conveying device. The method for producing a resin film according to claim 1 or 2, wherein the resin film is a polyimide resin film. A film before cutting, characterized by having: a central portion, which is composed of the first resin composition, and both ends, which are formed continuously from the central portion at both ends of the central portion, The both ends are made of a second resin composition different from the first resin composition, The tear strength of the two end portions is greater than the tear strength of the central portion. The film before cutting according to claim 4, wherein the first resin composition is a polyimide resin.

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