JP2008100476A - Polyethylene terephthalate resin film roll and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyethylene terephthalate resin film roll improved in the passing properties of a film in a heat treatment process at post processing over the whole length of the roll, extremely enhanced in transparency and having good slip properties. <P>SOLUTION: The polyethylene terephthalate resin film roll is obtained by coating at least one side of a film base material substantially containing no particles with a coating solution containing a copolyester resin and particles and drying the coated film base material to stretch the same at least in one direction to take up the stretched coated film base material. When ten sample cutting-off parts in total are provided at almost equal intervals from the winding finish of the film to the winding start of the film, all of the HSs 150 (heat shrinkage factors) at both left and right ends of the film become a value within a predetermined range and the difference between the HSs 150 at both left and right ends of the film becomes a value within the predetermined range in the respective cutting-off parts. Further, all of the variation quantities in the longitudinal direction of HSs 150 at both left and right ends of the cutting-off parts of the film are adjusted so as to become a value within the predetermined range. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a polyethylene terephthalate-based resin film roll, and particularly relates to a polyethylene terephthalate-based resin film roll having excellent processing characteristics.

  Biaxially oriented polyethylene terephthalate resin films are widely used as various optical films because of their excellent transparency, dimensional stability, and chemical resistance. In particular, it is suitably used for applications such as a prism lens sheet base film, an antiglare film base film, and a CRT anti-fracturing film for LCDs that require excellent strength and dimensional stability. Such a biaxially stretched polyethylene terephthalate-based resin film is stretched in the longitudinal direction between rolls having a difference in rotational speed, and then stretched in the width direction with the end of the film held in the tenter. It is manufactured by being heat-fixed at. Therefore, since the relaxation in the longitudinal direction cannot be promoted particularly at the edge of the film in the width direction at the end of the film, the thermal contraction rate in the longitudinal direction varies depending on the position of the slit roll in the film width direction. End up. Therefore, among the slit rolls that have slit the mill roll once wound in a wide width, in the slit roll corresponding to the edge of the mill roll, the heat shrinkage rate (longitudinal heat shrinkage rate) at one edge in the width direction is different. The phenomenon that it becomes larger than the thermal contraction rate at the edge occurs. And if such a distorted slit roll is used, the permeability of the film in the heat treatment process during post-processing such as prism lens processing, hard coat processing, and anti-glare (AR) processing is deteriorated, and the film is in the post-processing step. The situation which damages an edge part by rubbing with the frame of a machine stand, etc. will occur inside. Moreover, it is very troublesome to adjust the post-processing conditions on the user side so that the film is not damaged. As described above, since the slit roll corresponding to the edge of the mill roll is difficult to use for optical applications, only the slit roll other than the edge of the mill roll can be used for optical applications.

  In addition, there is an increasing demand for wide slit rolls in order to reduce post-processing costs, but in order to collect such wide slit rolls with a high yield from the limited mill roll width, the narrow width is required as in the past. It is better to collect from a wider mill roll than from a mill roll. However, when the mill roll is widened, it becomes difficult to maintain temperature uniformity in the width direction of the heat setting device. That is, a temperature difference occurs between the left and right, or the temperature becomes unstable over time. As a result, it becomes difficult to control the heat shrinkage rate constant in the width direction and the longitudinal direction. Therefore, in order to widen the mill roll, it is indispensable to finely adjust the hot air blowing amount and the like in order to keep the temperature uniformity in the width direction of the heat fixing device good. However, fine adjustment of the hot air blowing amount, etc. can improve the temperature uniformity in the width direction and reduce the difference in thermal shrinkage between the left and right to a certain extent. It is not possible to reduce the difference in thermal shrinkage between the left and right edges to a level sufficient to achieve the desired level.

  Therefore, regardless of the width of the mill roll, a method for reducing the difference in the heat shrinkage rate in the width direction of the film (the heat shrinkage rate in the longitudinal direction of the film) in order to improve the film passability in the post-processing step In the heat fixing process of the film, the applicant puts a continuous shielding plate on a plenum duct (hot air outlet) arranged at regular intervals with respect to the film traveling direction, and the width of the shielding plate By gradually expanding the film toward the film traveling direction side, the temperature in the width direction of the film is increased from the central part to the end part, and the relaxation amount at the end part approaches the relaxation amount at the central part. It has been proposed (Patent Document 1).

JP 2001-138462 A

  However, the film at the end cannot be sufficiently relaxed by a method in which a continuous shielding plate is placed on the plenum duct (hot air blowing portion) in the heat setting process. Therefore, although the passability is improved to some extent when heat treatment in post-processing (coating and drying) is performed at a low temperature of about 120 ° C., the drying efficiency of the coating film (hard coat film, etc.) is increased or coated. For the purpose of increasing the strength of the film, the passability when heat treatment in post-processing is performed in a high temperature zone (about 160 ° C.) for a relatively long time (10 to 60 seconds) is not so much improved. Therefore, when post-processing is performed at a high temperature for a long time, the conditions must be adjusted in the post-processing, and there may be a situation where the conditions cannot be adjusted.

  In addition, in the method of simply covering the plenum duct with the heat-fixing process, the temperature hunting in the heat-fixing zone becomes large, so when manufacturing a long film (mill roll) of 1,000 m or more. A portion having poor permeability (that is, a portion having a large difference in thermal shrinkage in the width direction of the film) is formed.

  Therefore, the applicants proposed a method for improving the film permeability in the heat treatment step during post-processing by covering the plenum duct with a shielding plate in a specific manner and performing heat setting treatment. (Japanese Patent Application No. 2006-159918). However, even when such a method is adopted, in order to express a high degree of transparency for use in special optical applications, etc., a film is formed using a polyethylene terephthalate resin that does not substantially contain particles. When it does, the slipperiness of a film will worsen, it will become impossible to wind up as a roll, and the favorable permeability in a post-processing process cannot be expressed.

  The purpose of the present invention is to solve the problems of the conventional film and the method for producing the same, and the film passage in the heat treatment process during post-processing is good over the entire length of the roll regardless of the conditions of the post-processing. An object of the present invention is to provide a polyethylene terephthalate-based resin film roll having extremely high transparency and excellent slipperiness. In addition, the object of the present invention is to inexpensively and easily produce a highly transparent polyethylene terephthalate-based resin film roll that has a very good film permeability in the heat treatment step during post-processing over the entire length of the roll. It is to provide a possible manufacturing method.

Among the present inventions, the structure of the invention described in claim 1 is a polyethylene terephthalate resin film slit to have a length of 300 m to 8,000 m and a width of 0.7 m to 2.2 m. The difference between the refractive index in the direction that forms an angle of 45 degrees with the winding direction of the wound film and the refractive index in the direction that forms an angle of 135 degrees with the winding direction of the wound film A polyethylene terephthalate-based resin film roll having a Δnab of 0.015 or more and 0.060 or less, and a water-dispersible or water-soluble copolymer on at least one surface of a film base material that does not substantially contain particles. A coating solution containing a polyester resin and particles is applied, dried, and then stretched and wound in at least one direction. The first sample cutout portion is provided within 2 m from the end of winding of the film, the final cutout portion is provided within 2 m from the start of film winding, and the length between the first and final cutout portions is divided into nine equal parts. When a total of 10 sample cutout portions are provided by providing the sample cutout portion, the following requirements (1) to (3) are satisfied, and the thickness of the wound polyethylene terephthalate resin film is It is 70 μm or more and 400 μm or less, and haze is 0.2 or more and 1.3 or less.
(1) When each sample is cut out from a position within 50 mm from one end edge and a position within 50 mm from the other end edge in the roll width direction, and the two samples are heated at 150 ° C. for 30 minutes. HS150, which is the heat shrinkage rate in the film winding direction, and when the heat shrinkage difference, which is the difference between the HS150, is obtained, the heat shrinkage difference in all cutout portions is 0.1% or less. (2) In each of the cutout portions, when a sample is cut out from a position within 50 mm from one end edge and a position within 50 mm from the other end edge in the width direction of the roll, and HS150 is obtained for each sample, HS150 of the samples at both end edges in all cutout parts is 0.7% or more and 2.0% or less 3) The fluctuation amount of the HS 150 on the one end edge side in the width direction of the roll obtained in each cutout portion and the fluctuation amount of the HS150 on the other end edge side in the width direction of the roll obtained in each cutout portion are both 0. 25% or less

  The structure of the invention described in claim 2 is that, in the invention described in claim 1, the amount of particles existing in the film is 1 ppm or more and 100 ppm or less.

The structure of the invention described in claim 3 is a manufacturing method for manufacturing the polyethylene terephthalate-based resin film roll described in claim 1 or 2, wherein the raw resin is melt-extruded from an extruder. A film forming step for forming an unstretched sheet, a biaxial stretching step for biaxially stretching the unstretched sheet obtained in the film forming step in the longitudinal direction and the transverse direction, and heat fixing the film after biaxial stretching A heat setting step, and the heat setting step is performed in a heat setting device that satisfies the following requirements (4) to (6).
(4) A plurality of wide plenum ducts for blowing out hot air are arranged vertically opposite to the traveling direction of the film. (5) Shielding for shielding hot air outlets from the plurality of plenum ducts. (6) The dimension of each shielding plate in the traveling direction of the film is adjusted to be substantially the same as the dimension of the outlet of each plenum duct in the traveling direction of the film. The dimension in the width direction of the film is adjusted so as to become gradually longer with respect to the film traveling direction.

  The structure of the invention described in claim 4 is the invention described in claim 3, wherein the biaxial stretching step stretches the film in the longitudinal direction and then stretches in the transverse direction and performs the transverse stretching. There is an intermediate zone between the zone and the heat fixing device in which no wind is blown.

  The structure of the invention described in claim 5 is the invention described in claim 3 or claim 4, wherein the heat setting device is divided into a plurality of heat setting zones and adjacent heat setting zones. In other words, the product of the temperature difference and the wind speed difference is set to be 250 ° C. · m / s or less.

  The polyethylene terephthalate-based resin film roll of the present invention has very high yield because it has excellent post-processing characteristics such as film passability in a heat treatment process such as prism lens processing, hard coat processing, and AR processing. Can be post-processed. Moreover, it is very transparent. Accordingly, the polyethylene terephthalate-based resin film roll of the present invention is used for various optical members such as a base film for a prism lens sheet, a base film for a backlight, a base film for an AR film, and a crush prevention film for a CRT. It can be suitably used as an optical film or a processing film in which heat treatment in other post-processing is performed for a relatively long time (10 to 60 seconds) in a high-temperature zone (about 160 ° C.).

  The film constituting the polyethylene terephthalate resin film roll of the present invention contains ethylene glycol and terephthalic acid as main components. Other dicarboxylic acid components and glycol components may be copolymerized as long as the object of the present invention is not impaired. Examples of the other dicarboxylic acid components include isophthalic acid, p-β-oxyethoxybenzoic acid, 2,6-naphthalenedicarboxylic acid, 4,4′-dicarboxybenzophenone, bis- (4-carboxyphenylethane), adipine Examples include acid, sebacic acid, 5-sodium sulfoisophthalic acid, cyclohexane-1,4-dicarboxylic acid, and the like. Examples of the other glycol component include propylene glycol, butanediol, neopentyl glycol, diethylene glycol, ethylene oxide adducts such as bisphenol A, polyethylene glycol, polypropylene glycol, and polytetramethylene glycol. In addition, oxycarboxylic acid components such as p-oxybenzoic acid can also be used.

  As a polymerization method of such polyethylene terephthalate (hereinafter simply referred to as PET), a direct polymerization method in which terephthalic acid and ethylene glycol and, if necessary, other dicarboxylic acid component and diol component are directly reacted, and dimethyl terephthalate are used. Any production method such as a transesterification method in which an ester (including a methyl ester of another dicarboxylic acid as necessary) and ethylene glycol (including another diol component as necessary) are transesterified can be used. .

  When the film roll of the present invention is formed of PET, the intrinsic viscosity (IV) of the raw material PET is preferably in the range of 0.45 to 0.70 dl / g. When the intrinsic viscosity of the PET raw material is 0.45 or less, the degree of polymerization of the PET after being recovered and passed through the extruder again becomes too low, and the stretchability of the film deteriorates or the tear resistance decreases. Is not preferable. On the other hand, if the intrinsic viscosity exceeds 0.70 dl / g, the filtration pressure becomes excessively high and high-precision filtration becomes difficult, which is not preferable. In addition, IV of resin raw material is calculated | required with the following methods, for example.

[Intrinsic viscosity (IV)]
After the PET ground sample is dried, it is dissolved in a mixed solvent of phenol / tetrachloroethane = 60/40 (weight ratio), and a solution having a concentration of 0.4 (g / dl) is obtained at 30 ° C. using an Ostwald viscometer. The flow time and the flow time of the solvent alone are measured, and the calculation is performed from the time ratio on the assumption that the constant of Huggins is 0.38 using the Huggins formula.

  Moreover, when forming the film roll of this invention by PET, the range of 3-30 eq / t is preferable and, as for the acid value (AV) of PET raw material, it is more preferable in it being 5-25 eq / t. An acid value of 3 eq / t or less is not preferable because the polymerization rate becomes slow and the production efficiency is lowered. On the other hand, an acid value of 30 eq / t or more is not preferable because hydrolysis tends to proceed and the degree of polymerization tends to decrease. The acid value of the resin raw material is determined by the following method, for example.

[Acid value]
After pulverizing the raw material, it is dissolved in benzyl alcohol, and after adding chloroform, neutralization titration with a sodium hydroxide solution is performed to calculate the equivalent of sodium hydroxide per 1 ton of PET.

  Furthermore, when the film roll of the present invention is formed of PET, it is desirable that the raw material (including the recycled raw material) before being introduced into the extruder does not contain foreign substances. In particular, in the case of producing a film roll for optical applications, when melt extrusion is performed, high-precision filtration is performed using a filter medium having a filtration particle size (initial filtration efficiency of 95%) of 15 μm or less, and the film after film formation It is preferable to adjust so that the number of foreign matters having a diameter of 20 μm or more present per 1 m 2 is 10 or less. Note that the number of foreign substances in the raw material is obtained by the following method, for example.

[Number of foreign objects]
An enlarged image of the melted raw material chip is taken using a phase contrast microscope and a CCD camera, and the number of foreign matters is counted using an image processing apparatus.

  The polyethylene terephthalate resin film roll of the present invention is a slit roll obtained by slitting a predetermined number of mill rolls once produced in a wide width, and makes an angle of 45 degrees with Δnab (that is, the winding direction of the wound film). The difference (absolute value) between the refractive index in the direction and the refractive index in the direction forming an angle of 135 degrees with the winding direction of the wound film is limited to 0.015 or more and 0.060 or less. That is, in the slit roll in which Δnab is less than 0.015, the above-mentioned problem of “distortion (that is, physical property difference in the width direction)” does not occur. Moreover, in the slit roll distorted so that Δnab exceeds 0.060, it is difficult to adjust the difference in thermal shrinkage rate so as to satisfy the requirements of the present invention. Note that Δnab in the present invention means Δnab measured at a position within 50 mm from one end edge of the slit roll and a position within 50 mm from the other end edge, and means the larger of the two values.

  The polyethylene terephthalate-based resin film roll of the present invention has a cut-out portion set by a method to be described later. At each cut-out portion, a position within 50 mm from one end edge in the roll width direction and within 50 mm from the other end edge. Each sample was cut out from each position, and for the two samples, HS150, which is the heat shrinkage rate in the film winding direction when heated at 150 ° C. for 30 minutes, was obtained, and the difference in heat shrinkage rate, which is the difference between the HS150, was obtained. The difference in heat shrinkage rate between all cutout parts must be 0.1% or less.

  That is, the polyethylene terephthalate-based resin film roll of the present invention has a total of 10 heat shrinkage ratio differences (difference in HS150 at both end edges in the film sample cut out from each cutout portion) obtained in a total of 10 cutout portions. Must be 0.1% or less. If the difference in thermal shrinkage at each cut-out portion exceeds 0.1%, the film passability in post-processing deteriorates, which is not preferable. Further, the difference in heat shrinkage rate between the cutout portions is more preferably 0.08% or less, and particularly preferably 0.06% or less. In addition, although the heat shrinkage rate difference in each cutout part is preferably as low as possible, it is considered that about 0.05% is the limit in consideration of measurement accuracy.

The cutting of the sample in the present invention is performed by cutting out a film sample from a cutting portion provided by the following procedure. In the following 3), “about every interval between cutout portions” means that the sample may be cut out at intervals of about ± 10 m between cutout portions.
1) The first sample cutout is provided within 2 m from the end of film winding.
2) A value obtained by dividing the length (winding length) of the wound film by 9 (hereinafter referred to as “cut-out portion interval”) is calculated.
3) A sample cutout portion is provided for each “cutout portion interval” from the end of winding of the film.
4) A final cutout is provided within 2 m from the start of film winding.

  The cutting of the sample will be described more specifically. For example, when a film having a length of 500 m is wound around a roll, the first sample (1) is cut within 2 m from the end of winding of the film. The sample is cut out in the film winding direction (longitudinal direction) including the position within 50 mm from one end edge and the position within 50 mm from the other end edge in the roll width direction (direction orthogonal to the film winding direction). (Direction) and a side along the width direction are cut into a rectangular shape (not cut obliquely). Next, the “cutting portion interval” is calculated by dividing the winding length of the film by 9. Note that the “cutout interval” is calculated to the unit of “1 m”. Therefore, as described above, when the winding length is 500 m, 2 m from the winding end where the first cutout portion can be provided and 2 m from the winding start where the final cutout portion can be provided are subtracted from 500 m in advance, and the remaining 496 m is obtained. 55 m divided into nine equal parts is defined as “interval of cutout portions”. Subsequently, the second sample (2) is cut out at a distance of 55 m from the winding end of the film toward the winding start side. Thereafter, similarly, samples are sequentially cut out at intervals of 55 m on the winding start side to obtain a total of 10 samples. That is, the first sample (first sample) is cut out at a position within 2 m from the end of winding, the second sample is cut out at a position near 57 m from the end of winding, and the third sample is cut at a position near 112 m from the end of winding. Similarly, the fourth to ninth samples are cut out at every position 55 m away from the end of winding, and the final sample (10th sample) is cut out at a position within 2 m from the start of winding.

  Furthermore, the polyethylene terephthalate-based resin film roll of the present invention has a position within 50 mm from one end edge in the width direction of the roll and within 50 mm from the other end edge when the sample cut-out part is set by the above-described method. When the sample is cut out from each position and the HS150 is obtained for each sample, the HS150 of the samples at both ends at all cutout portions must be 0.3% or more and 2.0% or less. is there.

  That is, in the polyethylene terephthalate-based resin film roll of the present invention, the HS150 values (total 20 HS150 values) at both ends of the cut film sample are 0.7% or more in a total of 10 cut portions. It is necessary to be 2.0% or less. If the value of HS150 at both ends of the film sample cut out from each cutout portion exceeds 2.0%, the film passability in post-processing deteriorates, which is not preferable. Further, the value of HS150 at both ends of the film sample cut out from each cut-out portion is more preferably 1.5% or less, and particularly preferably 1.2% or less. In addition, although the value of HS150 in the both ends of the film sample cut out from each cutout part is so preferable that it is low, about 0.7% is considered to be a minimum.

  Furthermore, the polyethylene terephthalate-based resin film roll of the present invention has a fluctuation amount of HS150 on one end edge side in the width direction of the roll obtained in each cutout part, and HS150 on the other end edge side in the roll width direction obtained in each cutout part. It is necessary that the fluctuation amount of each is 0.25% or less.

  That is, the polyethylene terephthalate-based resin film roll of the present invention has HS150 on one end edge side (one end edge side in the width direction) and HS150 on the other end side (the other end edge side in the width direction) for 10 films cut out from each cutout portion. , The fluctuation amount (difference between the highest value and the lowest value) of the ten HS 150 on the one edge side is 0.25% or less, and the fluctuation amount of the ten HS 150 on the other edge side is 0. It must be 25% or less. If the fluctuation amount of 10 HS 150 on either edge side exceeds 0.25%, it is not preferable because the passability of the film during post-processing deteriorates. Further, the fluctuation amount of the ten HS 150 on each edge side is more preferably 0.20% or less, and particularly preferably 0.15% or less. In addition, although the variation | change_quantity of 10 HS150 of each edge side is so preferable that it is low, when a measurement precision is considered, about 0.05% is considered to be a limit.

  The polyethylene terephthalate-based resin film roll of the present invention is an unstretched film (unstretched laminated film or unstretched laminated sheet) obtained by melting and extruding a polyethylene terephthalate-based resin resin chip as a raw material in the longitudinal direction (longitudinal direction) and After biaxial stretching in the transverse direction (width direction), the film can be wound into a roll and heat-fixed by the method described later.

  As a method for obtaining an unstretched sheet, polyethylene terephthalate-based resin pellets containing fine particles for the purpose of imparting slipperiness are sufficiently dried, then supplied to an extruder, and melt-extruded into a sheet at about 285 ° C. A method of cooling and solidifying the molten sheet with a cooling roll can be suitably employed.

  In addition, a well-known method can be applied to rapidly cool an unstretched sheet while bringing the sheet-like melt into close contact with the rotary cooling drum. For example, a method of using an air knife on the sheet-like melt or an electrostatic charge can be applied. A method of imprinting is preferably applicable. In those methods, the latter is preferably used.

  As a method of cooling the air surface of the sheet-like material, a known method can be applied. For example, a method of bringing the sheet surface into contact with a cooling liquid in the tank, a liquid evaporating with a spray nozzle on the sheet air surface You may use together the method of apply | coating, and the method of spraying a high-speed airflow and cooling. The unstretched sheet thus obtained is stretched in the biaxial direction to obtain a film.

  As a method of stretching the film in the biaxial direction, the obtained unstretched sheet is stretched in the longitudinal direction by a roll or a tenter-type stretching machine, and then stretched in the width direction orthogonal to the first-stage stretching direction. A method can be mentioned. The stretching temperature in the longitudinal direction is 75 to 120 ° C., and the stretching ratio in the longitudinal direction is 2.5 to 4.5 times, preferably 3.0 to 4.3 times. If the stretching temperature in the longitudinal direction is less than 75 ° C., the film tends to break, which is not preferable. On the other hand, when the temperature exceeds 120 ° C., the thickness unevenness of the obtained film is deteriorated, which is not preferable. When the draw ratio in the longitudinal direction is less than 2.5 times, the flatness of the obtained film is deteriorated, which is not preferable. On the other hand, if it exceeds 4.6 times, the orientation in the longitudinal direction becomes strong, and the frequency of breakage increases in stretching in the transverse direction, which is not preferable.

  In the case of stretching in the width direction, the stretching temperature needs to be 80 to 210 ° C, and preferably 130 to 200 ° C. If the stretching temperature in the width direction is less than 80 ° C., the film tends to break, which is not preferable. Moreover, when it exceeds 210 degreeC, since the planarity of the obtained film worsens, it is not preferable. The draw ratio in the width direction is 3.0 to 5.0 times, preferably 3.6 to 4.8 times. If the draw ratio in the width direction is less than 3.0 times, the thickness unevenness of the obtained film is deteriorated, which is not preferable. If the draw ratio in the width direction exceeds 5.0 times, the frequency of breaking increases in the drawing, which is not preferable.

  Subsequently, heat setting is performed. The temperature in the heat setting treatment step is preferably 180 ° C. or higher and 240 ° C. or lower. If the temperature of the heat setting treatment is less than 180 ° C., the absolute value of the heat shrinkage rate is increased, which is not preferable. On the other hand, if the temperature of the heat setting treatment exceeds 240 ° C., the film tends to become opaque and the frequency of breakage increases, which is not preferable. A suitable heat setting method will be described later.

  It is effective to control the heat shrinkage rate, particularly the heat shrinkage rate in the width direction, by narrowing the guide rail of the gripping tool by the heat setting process. The temperature for the relaxation treatment can be selected in the range from the heat setting treatment temperature to the glass transition temperature Tg of the polyethylene terephthalate resin film, and is preferably (heat setting treatment temperature) −10 ° C. to Tg + 10 ° C. The width relaxation rate is preferably 1 to 6%. If it is less than 1%, the effect is small, and if it exceeds 6%, the flatness of the film is deteriorated.

  Here, although the method of extending | stretching to the width direction after extending | stretching first to a longitudinal direction was described, the extending | stretching order may be reverse. In addition, the longitudinal stretching and the lateral stretching may be performed in one stage, or may be performed in two or more stages. In addition, as described above, in addition to the method of sequentially biaxially stretching an unstretched film, a simultaneous biaxial stretching method in which an unstretched film is simultaneously stretched in the machine direction and the transverse direction can be employed. However, in order to satisfy the characteristics of the present invention, it is important to take optimum temperature conditions and longitudinal and lateral draw ratios, and it is sufficient that the finally obtained film characteristics satisfy the requirements of the present invention.

  Further, in order to impart functionality to the film, a polyethylene terephthalate resin film having a multilayer structure of two or more layers may be used. When the surface on which the slippery layer or the easy adhesion layer is applied is the A layer, the opposite surface is the B layer, and the other surface is the C layer, the layer structure in the film thickness direction is A / B, A / C / B or Configurations such as A / C / E / D / B are conceivable. The layers A to E may be made of the same material or different materials.

  The thickness of the film constituting the polyethylene terephthalate resin film roll of the present invention is not particularly limited. However, when used for optical applications, it is preferable that the thickness is 70 μm or more and 400 μm or less.

  Further, the width of the film roll is not particularly limited, but from the viewpoint of ease of handling, the lower limit of the width of the film roll is preferably 0.7 m or more, and more preferably 1.0 m or more. . On the other hand, the upper limit of the width of the film roll is determined by the size of the customer's device to be post-processed. At present, 2.2 m is considered the maximum width, and it is more preferably 2.0 m or less. More preferably, it is 5 m or less. In addition, the winding length of the film roll is not particularly limited, but from the viewpoint of ease of winding and handling, when the film has a thickness of about 70 μm, it is preferably 8,000 m or less, and 7,000 m or less. Is more preferable. When the film has a thickness of about 400 μm, it is preferably 1,200 m or less, and more preferably 1,100 m or less. Therefore, when the thickness of the film is in the middle of 70 to 400 μm, it is preferable to set the film length to be 300 m or more and 8,000 m or less. As the take-up core, usually, paper of 3 inches, 6 inches, 8 inches, etc., a plastic core or a metal core can be used.

  The polyethylene terephthalate-based resin film of the present invention may be a single layer or a film having a laminated structure of two or more layers, and on one side or both sides of a biaxially stretched polyethylene terephthalate-based resin film that does not contain fine particles with emphasis on transparency. There is no problem even if various coatings are applied at the time of film formation for the purpose of improving the adhesiveness during the post-processing step and the purpose of improving the slipperiness.

  The polyethylene terephthalate resin film constituting the film roll of the present invention preferably contains substantially no fine particles (close to 0 ppm), but fine particles can be added as necessary. Examples of the fine particles added at that time include known inorganic fine particles and organic fine particles. In addition, content of the microparticles | fine-particles contained in a film is 0 ppm or more and 100 ppm or less, Preferably it is 80 ppm or less, More preferably, it is 50 ppm or less. Furthermore, in the resin forming the film, various additives as necessary, for example, waxes, antioxidants, antistatic agents, crystal nucleating agents, viscosity reducing agents, heat stabilizers, coloring pigments, An anti-coloring agent, an ultraviolet absorber and the like can be added.

  The polyethylene terephthalate resin film constituting the film roll of the present invention preferably has a haze value of 0.2 or more and 1.3 or less. If the haze value exceeds 1.3, the transparency becomes poor and it is not suitable for optical use, which is not preferable. The haze value is more preferably less than 1.0, and particularly preferably less than 0.8. Further, the haze value is preferably as small as possible, but in consideration of the fact that a predetermined amount of particles must be added to the film for the purpose of imparting the slipperiness required during production and post-processing, it is about 0.2. Becomes the lower limit.

  As a method of blending the above-mentioned particles into the polyethylene terephthalate resin film, for example, it can be added at any stage of producing the polyethylene terephthalate resin, but preferably after the esterification stage or after completion of the transesterification reaction. It may be added as a slurry dispersed in ethylene glycol or the like at the stage before the start of the condensation reaction to proceed the polycondensation reaction. Also, a method of blending a slurry of particles dispersed in ethylene glycol or water with a vented kneading extruder and a polyethylene terephthalate resin raw material, or a dried particle and a polyethylene terephthalate system using a kneading extruder It can be performed by a method of blending with a resin raw material.

  Furthermore, the polyethylene terephthalate resin film constituting the film roll of the present invention can be subjected to corona treatment, coating treatment, flame treatment, etc. in order to improve the adhesion of the film surface.

  Next, the preferable manufacturing method for obtaining the polyethylene terephthalate-type resin film roll of this invention is demonstrated.

  Usually, the heat setting process of the stretched film is often carried out in a heat setting device in which a plurality of plenum ducts having a long hot air outlet are arranged perpendicular to the longitudinal direction. And in the heat fixing device provided with such a plenum duct, in order to improve the heating efficiency, the air in the heat fixing device is sucked by the circulation fan attached to the heat fixing device, and then sucked. By adjusting the temperature of the air and exhausting it again from the hot air outlet of the plenum duct, "hot air circulation" is performed: "hot air blowing-> suction by a circulation fan-> temperature adjustment of sucked air-> hot air blowing" Is called.

  Further, as described above, the difference in heat shrinkage rate in the width direction of the film roll (difference between HS 150 at the edge of one end and HS 150 at the end of the other end) is the longitudinal direction at the end of the width direction of the film when heat-fixed. This occurs because it is not possible to promote relaxation. As shown in FIG. 1, a method of covering a central portion of the hot air outlets 2, 2,... Of the plenum ducts 3, 3,. In the case of a short film, the passability when the heat setting treatment in the post-processing is performed at a low temperature is improved, but the passability in the long film and the heat setting in the post-processing are improved. The passability when the treatment is performed at a high temperature is not improved at all.

  When the inventors attached a continuous large shielding plate to the hot air outlet of the plenum duct, why "passability in a long film" or "when heat fixing treatment in post-processing is performed at a high temperature In order to ascertain whether the “passability of” is not improved, the phenomenon in the heat setting device was analyzed in detail. As a result, when a continuous large shielding plate spanning a plurality of plenum ducts is put on the hot air outlet of the plenum duct, the flow of hot air blown from the hot air outlet of the plenum duct is significantly limited by the shielding plate, It has been found that a temperature hunting phenomenon occurs in the heat fixing device due to the fact that the above-mentioned "hot air circulation" is not performed smoothly.

The present inventors have described that the above-mentioned “temperature hunting phenomenon” induces insufficient thermal relaxation at the edge of the film, such as “passability in a long film” and “heat setting treatment in post-processing. It was speculated that it may have an adverse effect on the “passability when it is carried out at a high temperature”. Furthermore, the present inventors controlled the conditions such as the temperature and the air volume of the heat fixing device, and improved the coating method when covering the hot air outlet of the plenum duct with a shielding plate, thereby making the “hot air” described above. ”Circulation” can be performed smoothly, and “temperature hunting phenomenon” can be suppressed. As a result, “passability in long films” and “heat setting in post-processing are performed at high temperatures” It was speculated that it would be possible to improve the "passability when And as a result of trial and error to grasp the relationship between the temperature of the heat setting device, the air flow condition, the covering mode of the shielding plate, and the film permeability in the post-processing, the following (1) By adopting the means, there was a tendency that “passability in a long film” and “passability when heat-setting treatment in post-processing was performed at a high temperature” were improved. And based on the knowledge, as a result of further trial and error, the present inventors have taken the following means (1) and then taken the following means (2) and (3). The inventors have found that it is possible to obtain a film roll having good permeability, and have come up with the present invention.
(1) Adjustment of temperature and air volume of plenum duct in heat fixing device (2) Adjustment of shut-off condition of hot air outlet of plenum duct in heat fixing device (3) Heat cutoff between stretching zone and heat fixing device Each of the above-described means will be described sequentially.

(1) Adjustment of temperature and air volume of plenum duct in heat setting device In the production of the film roll of the present invention, the product of the temperature difference and the wind speed difference between adjacent heat setting zones of the heat setting device, It is essential to adjust the temperature and air volume of the hot air blown out from each plenum duct so that it becomes 250 ° C. · m / s or less. For example, when the heat setting device is divided into first to third heat setting zones, the product of the temperature difference and the wind speed difference between the first zone and the second zone, and between the second zone and the third zone. Both the product of the temperature difference and the wind speed difference need to be adjusted to be 250 ° C. · m / s or less. In such a case, a discontinuous shielding plate is attached to the hot air outlet of the plenum duct as described later by adjusting the temperature and air volume of the hot air blown from the hot air outlet of the plenum duct in each heat fixing zone. In addition, “circulation of hot air” in the heat setting device is executed smoothly, and “temperature hunting phenomenon” is effectively suppressed. However, it becomes possible to obtain a long film having a good length.

  When the product of the temperature difference and the wind speed difference between adjacent heat setting zones exceeds 250 ° C. · m / s (for example, the temperature difference between adjacent heat setting zones is set to 30 ° C. In addition, if the difference in wind speed between adjacent heat setting zones is set to 10 m / s), the “hot air circulation” in the heat setting device will not be performed smoothly, effectively preventing the “temperature hunting phenomenon”. Since it becomes impossible to suppress, it is not preferable. In addition, when the product of the temperature difference and the wind speed difference between the adjacent heat setting zones exceeds 250 ° C. · m / s, as an accompanying flow caused by the passage of the film, from the upstream heat setting zone to the downstream heat setting zone And the temperature difference between the flowing air becomes large, which adversely affects the temperature stability in the width direction of the downstream heat setting zone. The product of the temperature difference and the wind speed difference is preferably 200 ° C. · m / s or less, and more preferably 150 ° C. · m / s or less.

(2) Adjustment of Plenum Duct Shut-off Conditions in Heat Fixing Device In manufacturing the film roll of the present invention, as described above, the temperature and air volume of hot air blown from the hot air outlet of the plenum duct are adjusted in each heat fixing zone. Then, instead of attaching a large shielding plate across a plurality of plenum ducts arranged in the heat fixing device, as shown in FIG. 2, the hot air outlets (nozzles) 2 of the individual plenum ducts 3, 3,. It is necessary to attach rod-shaped shielding plates S, S,. In addition, when attaching a rod-shaped shielding plate to each plenum duct, the length of the shielding plate is gradually increased from the inlet to the outlet of the heat fixing device instead of attaching the same length of shielding plate to each plenum duct. It is preferable to lengthen the length (see FIG. 1). The material of the shielding plate is preferably the same material as the plenum duct in consideration of the thermal expansion in the heat fixing device, but can withstand the temperature of the heat fixing device and stain the film, There is no particular limitation as long as the film is not adhered.

(3) Blocking of heating between the stretching zone and the heat setting device (installation of an intermediate zone)
A biaxially stretched polyethylene terephthalate-based resin film roll is usually manufactured by heat-setting after being longitudinally and laterally stretched as described above, but in the production of the film roll of the present invention, it is longitudinally and laterally. Install an intermediate zone that does not blow active hot air between the zone to be stretched and the heat-fixing device to be heat-set, and completely shut off the heat between the drawing zone and the heat-fixing device. Is preferred. More specifically, the stretching zone and the heat setting device are adjusted to the same conditions as in the film production, and when the strip-shaped paper piece is hung between the stretching zone and the heat setting device in that state, the piece of paper is It is preferred to block the hot air from the stretching zone and the heat setting device so that it hangs almost completely in the vertical direction. In addition, the intermediate zone which does not perform such hot air blowing may be surrounded by a housing, or may be provided so that a continuously manufactured film is exposed. Insufficient blocking of the hot air in the intermediate zone is not preferable because the shielding effect of the shielding plate in the heat fixing device is insufficient, and good film permeability during post-processing cannot be obtained.

(4) Application of water-dispersible or water-soluble copolymerized polyester resin containing particles The polyethylene terephthalate-based resin film roll of the present invention is water-dispersible or water-soluble containing particles on at least one side of a base film. By applying the copolymerized polyester resin coating solution, an easy-sliding layer is formed on at least one surface of the base film. The easy-sliding layer is formed by applying a coating liquid containing a water-dispersible or water-soluble copolymerized polyester resin and drying it. The copolyester resin constituting the slippery layer is composed of two or more dicarboxylic acid components and one glycol component, one dicarboxylic acid component and two or more glycol components, or two or more dicarboxylic acid components and 2 Consists of more than one glycol component.

The coating liquid containing the copolymerized polyester resin may contain inert particles and / or waxes as particles for the purpose of imparting blocking resistance and slipperiness to the slippery layer. The mixing ratio of the particles to the copolymerized polyester resin is usually in the range of 1.0 to 20% by mass. Preferably, in order to make the transparency of the film 85% or more, the particles are blended at a ratio of 3.0 to 7.0% by mass with respect to the copolyester resin. The coating amount of the coating solution is preferably adjusted so that the final coating amount (solid content of the applied resin) in the stretched film is 0.02 to 0.20 g / m ² .

  The easy-sliding layer is formed by applying a coating solution containing the above components to at least one surface of the base film and drying it. For example, in the case of a coating liquid containing a water-dispersible copolymer polyester resin, preferably a water-dispersible sulfonic acid metal base-containing copolymer polyester resin, the solid content concentration is 2 to 10% by mass, and the viscosity is 2 to 40 cps (B-type viscosity). (Measured at 25 ° C. by a meter).

  As the dicarboxylic acid component, terephthalic acid and isophthalic acid are most preferable. If the amount is small, other aliphatic carboxylic acids such as dicarboxylic acid and adipic acid, particularly aromatic dicarboxylic acids such as diphenylcarboxylic acid may be added and copolymerized. In addition to the dicarboxylic acid component, in order to impart water dispersibility, the sulfonic acid metal base-containing dicarboxylic acid is preferably used in the range of 1 to 10 mol%. Examples of the sulfonic acid metal base-containing dicarboxylic acid include sulfonate terephthalic acid and 5-sulfonatoisophthalic acid, and 5-sulfonatoisophthalic acid is particularly preferable.

  Examples of the glycol component include ethylene glycol, propylene glycol, tetramethylene glycol, 1,4-cyclohexanedimethanol, neopentyl glycol, diethylene glycol, bisphenol A ethylene oxide adduct, and glycerin. Among these, it is preferable to use at least one branched glycol component.

  Examples of the branched glycol component include 2,2-dimethyl-1,3-propanediol, 2-methyl-2-ethyl-1,3-propanediol, and 2-methyl-2-butyl-1,3-propane. Diol, 2-methyl-2-propyl-1,3-propanediol, 2-methyl-2-isopropyl-1,3-propanediol, 2-methyl-2-n-hexyl-1,3-propanediol, 2 , 2-diethyl-1,3-propanediol, 2-ethyl-2-n-butyl-1,3-propanediol, 2-ethyl-2-n-hexyl-1,3-propanediol, 2,2- And di-n-butyl-1,3-propanediol, 2-n-butyl-2-propyl-1,3-propanediol, and 2,2-di-n-hexyl-1,3-propanediol. That.

  The branched glycol component is contained in the total glycol component in a proportion of preferably 10 mol% or more, more preferably 20 mol% or more. As the glycol component other than the above, ethylene glycol is most preferable. If it is a small amount, diethylene glycol, propylene glycol, butanediol, hexanediol, 1,4-cyclohexanedimethanol and the like may be used.

  Examples of the inert particles include silica, alumina-silica composite oxide, titanium oxide, calcium carbonate, calcium silicate, barium sulfate, calcium phosphate, aluminum oxide, magnesium oxide, silica, kaolinite, talc, mica and zeolite. Inorganic particles; organic particles such as crosslinked benzoguanamine resin and styrene resin. Of these, silica is preferable, and silica having an average particle diameter of 20 to 150 nm (nanometer) (average value of the maximum length when the film surface is observed with an electron microscope) is particularly preferable.

  Examples of the waxes include water-dispersible or water-soluble waxes such as higher fatty acid esters, carnauba wax, polyethylene glycol, polypropylene glycol, and polyethylene.

  As described above, by adopting the above methods (1) to (3), the “hot air circulation” in the heat fixing device can be smoothly executed, and the “temperature hunting phenomenon” can be suppressed. As a result, it is possible to sufficiently promote relaxation in the longitudinal direction at the edge of the width direction, such as “passability in a long film” and “passability when heat setting treatment in post-processing is performed at a high temperature”. Can be improved. In the above description, the method of suppressing the “temperature hunting phenomenon” by smoothly executing “circulation of hot air” in the heat fixing device in which the plenum duct is installed. The above description discloses the technical idea of how the film roll of the present invention can be obtained by applying thermal energy to the film at the production level. It can be easily carried out by a method different from the above-described method, and the film roll of the present invention can be obtained by a different method. In other words, even with another type of heat fixing device, the "circulation of hot air" is smoothly executed to suppress the "temperature hunting phenomenon" and then sufficiently relaxed in the longitudinal direction at the edge of the width direction. Improve "passability in long film" and "passability when heat-setting treatment in post-processing is performed at a high temperature" like the film roll of the present invention by applying sufficient heat energy to the film It is possible to obtain a finished film roll.

  Furthermore, by adopting the method (4) described above, not only “passability in a long film” and “passability when heat-setting treatment in post-processing is performed at a high temperature” are good. In addition, it is possible to obtain a film roll having high transparency and good slipperiness.

  Hereinafter, the present invention will be described in detail by way of examples. However, the present invention is not limited to the embodiments of the examples, and can be appropriately changed without departing from the spirit of the present invention. . Table 1 shows the film forming conditions of the film rolls in Examples and Comparative Examples.

[Example 1]
<Adjustment of coating solution>
First, as a dicarboxylic acid component (based on the entire dicarboxylic acid component), dimethyl terephthalate 49 mol%, dimethyl isophthalate 49 mol%, and 5-sulfonatoisophthalic acid 2 mol%, as a glycol component (based on the entire glycol component) A water-dispersible sulfonic acid metal base-containing copolymer polyester resin was prepared by carrying out a transesterification reaction and a polycondensation reaction by an ordinary method using 50 mol% of ethylene glycol and 50 mol% of neopentyl glycol.

  Next, 51.4 parts by mass of water, 38 parts by mass of isopropyl alcohol, 5 parts by mass of n-butyl cellosolve, and 0.06 mass of Megafac F-142D manufactured by Dainippon Ink & Chemicals, Inc., which is a surfactant. After mixing the parts, the mixture was heated and stirred. When the temperature reached 77 ° C., 5 parts by mass of the water-dispersible sulfonic acid metal base-containing copolymer polyester resin was added, and the mixture was continuously stirred until the resin no longer solidified. The liquid was cooled to room temperature to obtain a uniform water-dispersible copolymerized polyester resin liquid having a solid content concentration of 5.0% by mass.

  Further, 3 parts by mass of aggregated silica particles (Fuji Silysia Co., Ltd., Silicia 310) was dispersed in 50 parts by mass of water with a homogenizer at 1000 rpm for 1 hour, and then the above-mentioned water-dispersible copolyester resin solution 99.46. 0.54 parts by mass of an aqueous dispersion of silicia 310 was added to parts by mass, and 20 parts by mass of water was added with stirring to obtain coating solution A.

<Manufacture of film roll>
On the other hand, polyethylene terephthalate not containing fine particles (content 0 ppm) ([η] = 0.60) was dried so that the moisture content was 50 ppm, and then charged into a hopper immediately above the extruder. Melted at temperature. Further, when melting with an extruder, the molten resin was filtered with a filter material of a stainless sintered body (nominal filtration accuracy: 90% of particles having a size of 10 μm or more). Next, the melted resin is extruded as a sheet from a T-shaped die, and is wound around a casting drum whose surface is adjusted to 30 ° C. by using an electrostatic application casting method, and is cooled and solidified to obtain an unstretched sheet of 1,380 μm. Got.

Thereafter, the unstretched sheet described above is heated to 100 ° C. by a heated roll group and an IR heater, and then continuously stretched 3.5 times in the longitudinal direction with a roll group having a difference in peripheral speed. The coating solution A was applied to both sides of this film so that the wet coating amount was 6.5 g / m ² , dried at a temperature of 120 ° C., and then stretched 4 times in the width direction. Then, the end of the uniaxially stretched film was gripped with a clip, led to a hot air zone heated at 130 ° C., and continuously stretched 4.0 times in the width direction. Furthermore, a heat setting treatment is performed at 238 ° C. by a method described later, a transverse relaxation treatment of 1.7% is performed at 225 ° C., and a film having a thickness of 100 μm and a width of 3,300 mm is obtained by winding in a roll shape. A biaxially oriented polyester film roll (mill roll) wound up by 500 m was obtained. After that, while rolling the mill roll, the process of slitting the remaining portions into three at equal intervals in the width direction while removing both ends by 150 mm is repeated, and approximately 200 m is excluded from the surface layer (winding end portion) of the mill roll. Thus, six slit rolls having a width of 1,000 mm and a winding length of 3,010 m were obtained.

<Heat setting process>
The heat setting process was performed by a heat setting apparatus having a structure as shown in FIG. The heat setting device is divided into four heat setting zones called first to fourth zones, and eight plenum ducts a to x are provided in the first to third zones, respectively. In addition, eight plenum ducts are provided. Each plenum duct is vertically installed at 400 mm intervals with respect to the film traveling direction so as to be perpendicular to the film traveling direction. And hot air is sprayed on the film extended | stretched from the hot air blowing outlet (nozzle) of those plenum ducts.

  In Example 1, discontinuous rod-shaped shielding plates S, S,... Were attached to the hot air outlets of 15 plenum ducts a to o in the manner shown in FIG. FIG. 4 shows a state where the heat fixing device having the shielding plates S, S,... Attached to the hot air outlets of the plenum ducts a to o is viewed from above, and each of the attached shielding plates S, S,. The center in the longitudinal direction is set so as to substantially coincide with the center of the width of the film passing through the heat fixing device. Further, the length of each shielding plate S, S... (The dimension in the width direction of the film to be manufactured) is adjusted so that it gradually becomes wider (that is, widens toward the end) from the inlet to the outlet of the heat fixing device. Has been. Table 2 shows the shielding ratio of the hot air outlets of each of the plenum ducts a to o (the shielded area of the hot air outlet by the shielding plate / the area of the hot air outlet). In addition, let the shielding aspect by the shielding board in Example 1 be "A aspect."

  In Example 1, the temperatures and wind speeds in the first to fourth zones of the heat setting device were adjusted as shown in Table 3. In addition, in the temperature conditions of the 1st-4th zone of the heat setting apparatus of Example 1, and the wind speed conditions, the product of the temperature difference between the adjacent heat setting zones and the wind speed difference is 250 ° C. · m / s or less. In addition, let the temperature of 1st-4th zone in Example 1, and wind speed conditions be "I conditions."

[Characteristic evaluation of film roll]
Among the six slit rolls obtained as described above, using the slit roll corresponding to one edge side of the mill roll (the right side when viewed downstream from the upstream of the film flow) Evaluation was performed. Further, in the measurement of the heat shrinkage rate, the first sample cutout portion is provided within 2 m from the end of film winding, and the sample cutout portion is provided for each length obtained by dividing the film winding length into nine equal parts from the end of film winding. At the same time, by providing the final cutout portion within 2 m from the beginning of winding of the film, a total of 10 sample cutout portions were provided for one slit roll, and the sample film was cut out from the 10 sample cutout portions. The evaluation results are shown in Table 4.

[Δnab]
After leaving each sample film cut out from each sample cut-out part in an atmosphere of 23 ° C. and 65% RH for 2 hours or more, using the “Abbe refractometer 4T type” manufactured by Atago Co., Ltd. Refractive index in a direction that forms an angle of 45 degrees with the winding direction, and a direction that forms an angle of 135 degrees with the winding direction of the wound film (that is, the direction that forms the angle of 45 degrees and 90 degrees described above) The refractive index in the direction forming the angle was measured. Then, the absolute value of the difference between the two refractive indexes was calculated as Δnab.

[Heat shrinkage of film]
A 200 mm mark was inserted in the direction of measurement at a sample width of 20 mm, and the sample was placed in a heating oven adjusted to 150 ° C., and the amount of heat shrinkage was measured in accordance with JIS C-2318.

[Passability of film]
The slit roll was heat-treated using a coater having a distance between the two rolls of 1,900 mm, setting the temperature to 100 ° C., and setting the furnace tension to 100 N. Subsequently, in order to evaluate the flatness of the film, the film was passed through two horizontally disposed rolls having a roll interval of 2,000 mm under a tension of 98 N. At the center position between the rolls with a roll interval of 2,000 mm, an iron bar is arranged so that the upper surface of the iron bar is located 30 mm below the common tangent line of the upper surface of the horizontally arranged roll, and passes through the film. When the film was not in contact with the iron bar, it was marked as ◯, and when it was in contact with the iron bar, it was marked as x. These steps were performed continuously, and it was visually confirmed whether or not the film contacted the iron bar.

[Haze]
Based on JIS-K-7136, it measured using the haze meter (Nippon Denshoku Industries Co., Ltd. make, 300A). In addition, the measurement was performed twice and the average value was calculated | required.

[Dynamic friction coefficient (μd)]
In accordance with ASTM-D-1894, using a tensile tester (TENSILON RTC-1225A manufactured by ORIENTEC), the dynamic friction coefficient μd when the front and back surfaces of the film are joined in a 23 ° C./65% RH environment. Obtained (measured 5 times and calculated the average value). The weight of the thread (weight) wound with the upper film was 3.5 kg, and the size of the bottom area of the thread was 95 mm long × 90 mm wide. In addition, the tensile speed at the time of friction measurement is 200 mm / min. Met. In Table 4, those with μd of less than 0.45 are shown as “◯”, those with 0.45 or more and less than 0.80 are shown as “Δ”, and those with 0.80 or more are shown as “x”.

[Measurement method of coating thickness]
The film sample was allowed to cure at room temperature with a visible light curable resin (for example, epoxy resin), then an ultrathin section was prepared using an ultramicrotome equipped with a diamond knife, and stained with ruthenium tetroxide. ) Using a TEM2010 manufactured by the company, a cross-sectional photograph of the film (magnification is Direct Mas × 30000, Final Mag × 76200 at an acceleration voltage of 200 kv), and an average of five points measured in the width direction of the coating thickness from this photograph The value is calculated as the coating thickness.

[Example 2]
Increase the melt extrusion amount by the extruder to increase the width of the unstretched film, and change the shielding plate attached to the hot air outlet of each plenum duct of the heat fixing device so as to have a shielding rate as shown in Table 2. The temperature and wind speed in the first to fourth zones of the heat setting device were changed as shown in Table 3. Also, the fine particles added to the coating solution were changed to Mizusukacil P705 manufactured by Mizusawa Chemical. Other than that was carried out similarly to Example 1, and obtained the mill roll which wound up 6,500m of the film of width 100mm and width 5300mm. After that, while rolling the mill roll, the process of slitting the remaining part into 5 parts at equal intervals in the width direction while removing both ends by 150 mm is repeated, and by removing approximately 200 m from the surface layer of the mill roll, the width 1 Ten slit rolls having a winding length of 3,010 m at 1,000 mm were obtained. Of the 10 slit rolls obtained as described above, a film and a film roll using a slit roll corresponding to one edge side of the mill roll (the right side when viewed from the upstream side of the film flow) Evaluation of characteristics was performed. The evaluation results are shown in Table 4. In addition, the shielding mode by the shielding plate in Example 2 is referred to as “B mode”, and the temperature and wind speed conditions in the first to fourth zones in Example 2 are referred to as “II conditions”.

[Example 3]
When adjusting the coating solution, 49 mol% dimethyl terephthalate, 49 mol% dimethylisophthalate, and 2 mol% 5-sulfonatoisophthalic acid as the dicarboxylic acid component (relative to the entire dicarboxylic acid component), (glycol as the glycol component) Using 70 mol% ethylene glycol and 30 mol% neopentylglycol, the transesterification reaction and polycondensation reaction are carried out in a conventional manner to prepare a water-dispersible sulfonic acid metal base-containing copolymer polyester resin. did. Thereafter, using the prepared water-dispersible sulfonic acid metal base-containing copolymer polyester resin, a uniform water-dispersible copolymer polyester resin solution having a solid content concentration of 5.0% by mass was prepared in the same manner as in Example 1. Then, the coating liquid B was obtained by adding fine particles in the same manner as in Example 1. Then, six slit rolls obtained by winding a film having a thickness of 100 μm to a width of 1,000 mm and a winding length of 3,010 m in the same manner as in Example 1 except that the obtained coating liquid B was applied after longitudinal stretching. Got. Of the six slit rolls obtained as described above, a film and a film roll using a slit roll corresponding to one end side of the mill roll (the right side when viewed downstream from the upstream of the film flow) Evaluation of characteristics was performed. The evaluation results are shown in Table 4.

[Comparative Example 1]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. Then, six slit rolls were obtained in the same manner as in Example 1 except that the coating solution was not applied, by winding a film having a thickness of 100 μm to a width of 1,000 mm and a winding length of 3,010 m. Of the six slit rolls obtained as described above, a film and a film roll using a slit roll corresponding to one end side of the mill roll (the right side when viewed downstream from the upstream of the film flow) Evaluation of characteristics was performed. The evaluation results are shown in Table 4.

[Comparative Example 2]
Three slit rolls in the same manner as in Example 1 except that an integrated large shielding plate is attached to the hot air outlet of each of the plenum ducts a to o of the heat setting device used for heat setting processing. Got. The shape of the shielding plate was adjusted so that the shielding rate by the large shielding plate was the same as in Example 1. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 1. The evaluation results are shown in Table 4.

[Comparative Example 3]
An attempt was made to produce a film roll in which a film having a thickness of 100 μm and a width of 1,000 mm was wound up in the same manner as in Example 1 except that the coating solution was not applied, but the slipperiness of the film was insufficient. A film roll having a good appearance could not be obtained. The characteristics of the obtained short film were evaluated by the same method as in Example 1. The evaluation results are shown in Table 4.

[Comparative Example 4]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. Other than that was carried out similarly to Example 1, and obtained six slit rolls which wound the film of 100 micrometers in thickness with the width of 1,000 mm to the winding length of 3,010 m. Of the six slit rolls obtained as described above, a film and a film roll using a slit roll corresponding to one end side of the mill roll (the right side when viewed downstream from the upstream of the film flow) Evaluation of characteristics was performed. The evaluation results are shown in Table 4.

[Reference Example 1]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. Moreover, when producing the unstretched sheet, the amount of melt extrusion by the extruder was increased, and the width of the unstretched film was increased from the width of the unstretched film of Example 1. Then, the shielding plate attached to the hot air outlet of each plenum duct of the heat setting device used for heat setting processing is changed to have the shielding rate as shown in Table 2, and the temperature and wind speed of the first to fourth zones of the heat setting device are changed. Was changed as shown in Table 3, and a mill roll was obtained by winding a film having a thickness of 100 μm and a width of 5,300 mm to 6,500 m in the same manner as in Example 1 except that the coating solution was not applied. After that, while rolling the mill roll, the process of slitting the remaining part into 5 parts at equal intervals in the width direction while removing both ends by 150 mm is repeated, and by removing approximately 200 m from the surface layer of the mill roll, the width 1 Ten slit rolls having a winding length of 3,010 m at 1,000 mm were obtained. Of the 10 slit rolls obtained as described above, a film and a film roll using a slit roll corresponding to one edge side of the mill roll (the right side when viewed from the upstream side of the film flow) Evaluation of characteristics was performed. The evaluation results are shown in Table 4.

[Reference Example 2]
In place of polyethylene terephthalate not containing fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.0065 wt% of silica having an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. When extruding and cooling and solidifying, the take-off speed was lowered to increase the thickness of the unstretched sheet to 2,440 μm. Then, a film having a thickness of 188 μm and a width of 3,300 mm was formed in the same manner as in Example 1 except that the stretching operation in the longitudinal direction was changed to a 3.3-fold stretching operation and the coating liquid was not applied. A mill roll wound up 4,500 m was obtained. After that, while rolling the mill roll, the process of slitting the remaining part into three at equal intervals in the width direction while removing both ends by 150 mm is repeated, and by removing approximately 200 m from the surface layer of the mill roll, the width 1 Six slit rolls having a winding length of 2,010 m at 2,000 mm were obtained. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 1. The evaluation results are shown in Table 4.

[Reference Example 3]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle size of 0.7 μm was used as an additive and melted in the same manner as in Example 2. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And when extending | stretching and heat-setting the obtained unstretched film, the shielding board attached to the hot-air blowing outlet of each plenum duct of a heat setting apparatus was changed so that it might become a shielding rate as shown in Table 2, Three slit rolls were obtained in the same manner as in Example 1 except that the temperatures and wind speeds of the first to fourth zones were changed as shown in Table 3. Note that the temperature and wind speed conditions in the first to fourth zones in Example 4 are referred to as “III conditions”. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 1. The evaluation results are shown in Table 4.

[Comparative Reference Example 1]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And, when the obtained unstretched film was stretched and heat-fixed, the example except that an integrated large-sized shielding plate was attached to the hot air outlet of each of the plenum ducts a to o of the heat fixing device In the same manner as in Example 1, three slit rolls were obtained. The shape of the shielding plate was adjusted so that the shielding rate by the large shielding plate was the same as in Example 1. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 1. The evaluation results are shown in Table 4.

[Comparative Reference Example 2]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle size of 0.7 μm was used as an additive and melted in the same manner as in Example 2. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And when extending | stretching and heat-setting the obtained unstretched film, the temperature of the 1st-4th zone of a heat setting apparatus and a wind speed are changed as Table 3, and each plenum duct of a to v of a heat setting apparatus is changed. Three slit rolls were obtained in the same manner as in Example 2 except that an integrated large-sized shielding plate was attached to the hot air outlet. The shape of the shielding plate was adjusted so that the shielding rate by the large shielding plate was the same as in Example 2. In addition, the temperature and wind speed conditions of the first to fourth zones in Comparative Example 2 are referred to as “IV conditions”. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 2. The evaluation results are shown in Table 4.

[Comparative Reference Example 3]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle size of 0.7 μm was used as an additive and melted in the same manner as in Example 2. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And when extending | stretching and heat-setting the obtained unstretched film, the temperature of the 1st-4th zone of a heat setting apparatus and a wind speed are changed as Table 3, and each plenum duct of a to v of a heat setting apparatus is changed. Three slit rolls were obtained in the same manner as in Example 2 except that an integrated large-sized shielding plate was attached to the hot air outlet. The shape of the shielding plate was adjusted so that the shielding rate by the large shielding plate was the same as in Example 2. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 2. The evaluation results are shown in Table 4.

[Comparative Reference Example 4]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And, when the obtained unstretched film is stretched and heat-set, the shielding mode by the rod-shaped shielding plate attached to the hot air outlet of each plenum duct of the heat fixing device a to o is changed as shown in Table 2, Three slit rolls were obtained in the same manner as in Example 1 except that the temperatures and wind speeds of the first to fourth zones of the heat setting device were changed as shown in Table 3. In addition, the length (dimension in the width direction of the film to be manufactured) of each shielding plate in Comparative Reference Example 4 is adjusted so as to become gradually narrower from the inlet to the outlet of the heat fixing device. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 1. The evaluation results are shown in Table 4.

[Comparative Reference Example 5]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle diameter of 0.7 μm was used as an additive and melted in the same manner as in Example 1. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And when stretching and heat fixing the obtained unstretched film, while performing heat fixing without attaching a shielding plate to the hot air outlet of each plenum duct, the temperature of the first to fourth zones of the heat fixing device, Three slit rolls were obtained in the same manner as in Example 1 except that the wind speed was changed as shown in Table 3. The temperature and wind speed conditions in the first to fourth zones in Comparative Reference Example 5 are referred to as “VI conditions”. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 1. The evaluation results are shown in Table 4.

[Comparative Reference Example 6]
Instead of polyethylene terephthalate that does not contain fine particles, polyethylene terephthalate ([η] = 0.60) containing 0.03 wt% of silica with an average particle size of 0.7 μm was used as an additive and melted in the same manner as in Example 2. The unstretched sheet | seat of 1,380 micrometers was obtained by extruding and making it cool and solidify. And when stretching and heat fixing the obtained unstretched film, while performing heat fixing without attaching a shielding plate to the hot air outlet of each plenum duct, the temperature of the first to fourth zones of the heat fixing device, Five slit rolls were obtained in the same manner as in Example 2 except that the wind speed was changed as shown in Table 3. And the characteristic of a film and a film roll was evaluated using the slit roll in the same position as Example 2. The evaluation results are shown in Table 4.

[Effects of Example Film]
From Table 4, the film rolls of the examples all have a small difference in heat shrinkage rate (that is, a difference in heat shrinkage rate) over the entire width of the roll, and also a small amount of variation in the heat shrinkage rate in the longitudinal direction. It can be seen that the passability in is good and suitable for post-processing. It can also be seen that the transparency is extremely high (has a low haze), and that the slipperiness is good (the coefficient of dynamic friction is small). On the other hand, the film roll of the comparative example has low transparency, poor slipperiness, a large difference in heat shrinkage rate over the entire width of the roll, and a large fluctuation amount of the heat shrinkage rate in the longitudinal direction. It can be seen that the passability during post-processing is poor.

  Since the polyethylene terephthalate resin film roll of the present invention has excellent processing characteristics as described above, the heat treatment in the optical film used for various optical members and other post-processing is performed in a high temperature zone (160 ° C. It can be suitably used as a film for processing performed over a relatively long time (10 to 60 seconds).

Explanatory drawing which shows the shielding aspect by the conventional shielding board (a is a partial cross section of the heat fixing device, and b is the state where the shielding board is attached to the hot air outlet of the plenum duct from above. It shows what you saw). BRIEF DESCRIPTION OF THE DRAWINGS It is explanatory drawing which shows the shielding aspect by the shielding board in this invention (a is a partial vertical cross section of a heat fixing apparatus, b is the state which attached the shielding board to the hot-air blowing outlet of the plenum duct. Is a view from above.) It is explanatory drawing which shows the state which saw through the heat fixing apparatus used by the Example and the comparative example from the top. It is explanatory drawing which shows the shielding aspect by the shielding board in Example 1. FIG.

Explanation of symbols

  1. Heat fixing device, 2. Hot air outlet, ax ... Plenum duct, F ... Film, S ... Shield plate.

Claims (5)

Winding a polyethylene terephthalate resin film slit to have a length of 300 m to 8,000 m and a width of 0.7 m to 2.2 m,
Δnab, which is the difference between the refractive index in the direction that forms an angle of 45 degrees with the winding direction of the wound film and the refractive index in the direction that forms an angle of 135 degrees with the winding direction of the wound film, is 0. A polyethylene terephthalate-based resin film roll of 015 or more and 0.060 or less,
A coating solution containing a water-dispersible or water-soluble copolymer polyester resin and particles is applied to at least one surface of a film base that does not substantially contain particles, and after drying, it is stretched in at least one direction. And can be obtained by winding
The first sample cutout is provided within 2 m from the end of winding of the film, the final cutout is provided within 2 m from the start of winding of the film, and the length between the first and final cutout is divided into nine equal parts. When a total of 10 sample cutout portions are provided by providing a sample cutout portion, the following requirements (1) to (3) are satisfied, and
A polyethylene terephthalate resin film roll having a wound polyethylene terephthalate resin film having a thickness of 70 μm to 400 μm and a haze of 0.2 to 1.3.
(1) When each sample is cut out from a position within 50 mm from one end edge and a position within 50 mm from the other end edge in the roll width direction, and the two samples are heated at 150 ° C. for 30 minutes. HS150, which is the heat shrinkage rate in the film winding direction, and when the heat shrinkage difference, which is the difference between the HS150, is obtained, the heat shrinkage difference in all cutout portions is 0.1% or less. (2) In each of the cutout portions, when a sample is cut out from a position within 50 mm from one end edge and a position within 50 mm from the other end edge in the width direction of the roll, and HS150 is obtained for each sample, HS150 of the samples at both end edges in all cutout parts is 0.7% or more and 2.0% or less 3) The fluctuation amount of the HS 150 on the one end edge side in the width direction of the roll obtained in each cutout portion and the fluctuation amount of the HS150 on the other end edge side in the width direction of the roll obtained in each cutout portion are both 0. 25% or less   The polyethylene terephthalate resin film roll according to claim 1, wherein the amount of particles present in the film is 1 ppm or more and 100 ppm or less. A manufacturing method for manufacturing the polyethylene terephthalate-based resin film roll according to claim 1 or 2,
A film forming process for forming an unstretched sheet by melt-extruding a raw material resin from an extruder, a biaxial stretching process for biaxially stretching the unstretched sheet obtained in the film forming process in the longitudinal direction and the transverse direction, A heat setting step of heat fixing the film after axial stretching,
The manufacturing method of the polyethylene terephthalate-type resin film roll characterized by performing the heat setting process in the heat setting apparatus which satisfy | fills the following requirements (4)-(6).
(4) A plurality of wide plenum ducts for blowing out hot air are arranged vertically opposite to the traveling direction of the film. (5) Shielding for shielding hot air outlets from the plurality of plenum ducts. (6) The dimension of each shielding plate in the traveling direction of the film is adjusted to be substantially the same as the dimension of the outlet of each plenum duct in the traveling direction of the film. The dimension in the width direction of the film is adjusted so as to become gradually longer with respect to the film traveling direction.   In the biaxial stretching process, the film is stretched in the transverse direction after stretching the film in the longitudinal direction, and an intermediate zone that does not perform wind blowing is provided between the zone that performs the transverse stretching and the heat setting device. The method for producing a polyethylene terephthalate-based resin film roll according to claim 3.   The heat setting device is divided into a plurality of heat setting zones, and the product of the temperature difference and the wind speed difference between adjacent heat setting zones is set to be 250 ° C. · m / s or less. The method for producing a polyethylene terephthalate-based resin film roll according to claim 3 or 4, wherein:

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