JP2006015742A - Polyamide resin laminated film roll and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a biaxially oriented polyamide resin film roll smoothly susceptible to bag making processing due to lamination in a good yield and capable of efficiently obtaining a package extremely high in peel strength and hot water peel strength and having no S-shaped curl. <P>SOLUTION: This polyamide resin laminated film roll is constituted so that an adhesion modifying layer comprising a copolyester is laminated, the first sample cutting part is provided within a range of 2 m from the winding end of a film and the final cutting part is provided within a range of 2 m from the winding start of the film. In a case that a sample cutting part is provided at every about 100 m from the first sample cutting part, all of samples cut from the respective cutting parts are adjusted so that physical properties such as a boiling water shrinkage factor, a refractive index or the like in a thickness direction become fluctuation width within a predetermined range. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a high-quality film roll having uniform physical properties over a long length obtained by winding a polyamide resin film, and more specifically, used for packaging retort foods by laminating with a polyolefin resin film. It is related with the polyamide-type resin film roll with the favorable workability in making.

  Biaxially oriented polyamide resin film mainly composed of nylon is tough and has excellent gas barrier properties, pinhole resistance, transparency, printability, etc., so it can be used for various liquid foods, water-containing foods, frozen foods, It has been widely put into practical use as a packaging material for various foods such as retort foods, pasty foods, livestock meat and fishery foods, and in recent years, it has been widely used for packaging retort foods. Such a polyamide-based resin film is laminated with, for example, a polyolefin-based resin film such as polyethylene or polypropylene, folded in two parallel to the flow direction, then heat-sealed on three sides, and opened on one side. The three-side sealed bag is in a state, filled with various foods and the like, sealed, and then heat-sterilized in boiling water for market.

  However, when a biaxially oriented polyamide-based resin film is used, there is a phenomenon in which the corners of the packaging bag are warped after heat sterilization and the four sides curl into an S shape (hereinafter referred to as an S-curl phenomenon). It may occur and the appearance as a packaged product may be remarkably deteriorated. Therefore, as a method of reducing such curling phenomenon, as in Patent Document 1, the product of boiling water shrinkage strain rate and change rate of molecular orientation angle in the film width direction in a biaxially oriented polyamide resin film is adjusted to a specific value. In order to improve dimensional stability during boiling water treatment, it is necessary to extremely increase the temperature during heat setting or excessively perform relaxation heat treatment after stretching. Therefore, there arises a problem that the toughness and pinhole resistance of the obtained film are impaired.

  Therefore, as described in Patent Document 2, the applicants adjust the boiling water shrinkage and refractive index of the film to a specific numerical range, thereby reducing the S-curl phenomenon without reducing toughness and pinhole resistance. Invented and proposed a method for obtaining a biaxially oriented polyamide-based resin film that does not cause the problem.

Japanese Patent Laid-Open No. 4-103335 JP-A-8-174663

  According to the method of Patent Document 2 described above, it is possible to obtain a biaxially oriented polyamide-based resin film that is tough and excellent in pinhole resistance and does not cause an S-curl phenomenon. However, in the bag making process by lamination, the conditions such as pressure and time when heat-sealing are finely adjusted for each film roll used, so the boiling water shrinkage and refractive index of the film wound around the film roll Even in the case where the average value of physical property values such as is within the range of Patent Document 2, if the amount of fluctuation in one film roll is large, there is a wrinkle between the films when laminating in the bag making process. And troubles such as poor yield are likely to occur.

  On the other hand, in the manufacturing method of a biaxially stretched film roll for winding a biaxially stretched film after mixing and extruding a mixture of a plurality of resins, the applicants as raw material chips Proposed a method for reducing the segregation of the raw material by making the shape of the same and increasing the inclination angle of the funnel-like hopper which is a raw material supply unit to the extruder (Japanese Patent Laid-Open No. 2004-181777). However, this method is not necessarily a definitive method as a method for suppressing fluctuations and variations in physical properties such as boiling water shrinkage and refractive index of a film wound on a film roll.

  Therefore, as a result of earnestly examining the production technology for producing highly uniform biaxially stretched film rolls, the applicants have highly uniform physical properties such as film thickness, boiling water shrinkage rate and refractive index, The inventors have invented a polyamide-based resin film roll that can be formed with a high yield without causing wrinkles between the films when laminating (Japanese Patent Application No. 2004-262922).

  According to the polyamide resin film roll having highly uniform physical properties such as film thickness, boiling water shrinkage and refractive index as described above, the S-curl phenomenon is maintained without deteriorating the good toughness and pinhole resistance of the polyamide resin film. The processability at the time of laminating can be made good without causing the above. However, the polyamide-based resin film alone has a limit in the peel strength at the time of lamination, and is not necessarily suitable for packaging applications such as fresh food products. Also, as a method for increasing the peel strength when laminating, generally, an adhesive layer is formed on the surface of a biaxially stretched polyamide film, and a sealant layer is formed thereon by a dry laminating method or an extrusion laminating method. A method of providing a heat-sealable polyamide film laminate is known. The film laminate is printed as necessary, and then molded into a bag shape, and the contents, for example, seasonings such as miso and soy sauce, water-containing foods such as soup and retort foods, chemicals, etc. After filling, the open portion is heat-sealed to provide a packaged product provided to general consumers.

  However, if the physical properties of the polyamide-based resin film are non-uniform, the characteristics of the laminated polyamide film in which the sealant layer and the like are laminated also become non-uniform, resulting in variations in peel strength when laminated.

  On the other hand, when moisture penetrates into each layer forming the polyamide film laminate having the sealant layer as described above, there is a problem that the adhesive strength between the layers is remarkably reduced. This causes damage when used as a packaging bag. For example, when a retort food bag using a polyamide film laminate having a sealant layer is subjected to boiling water treatment or retort treatment, this problem appears remarkably, and the bag is more easily damaged. In addition, as multi-color printing on the entire surface becomes widespread as packaging products become more expensive, problems such as a decrease in interlayer adhesion due to the presence of a printing ink layer also arise. Furthermore, when an adhesive layer is interposed between the biaxially stretched polyamide film layer and the sealant layer, depending on the type of the adhesive, it is easily affected by the adhesive force depending on the humidity, and in particular, a humidity curable adhesive is used. In some cases, the effect appears prominently, and there is a problem that the adhesive strength varies greatly depending on the season.

  The present invention has been achieved as a result of earnest research and development on production technology for producing a polyamide-based resin laminated film roll having a highly uniform peel strength when laminated, and the object thereof is the conventional polyamide This eliminates the problems associated with resin-based laminated film rolls, has extremely high peel strength when laminated, and is highly uniform, making it possible to carry out bag-making by lamination smoothly and with almost no trouble. An object of the present invention is to provide a polyamide-based resin laminated film roll capable of efficiently obtaining an unwrapped package. Another object of the present invention is to provide a polyamide-based resin laminated film roll capable of obtaining a processed product with a high yield in post-processing such as bag making. In addition, it is providing the manufacturing method which can manufacture such a polyamide-type resin laminated | multilayer film roll efficiently.

Among the present inventions, the structure of the invention described in claim 1 is such that an adhesion modified layer made of a copolymerized polyester is laminated on at least one side, the width is 0.2 m or more and 3.0 m or less, and the length is 300 m. A polyamide-based resin laminated film roll obtained by winding a polyamide-based resin film having a length of 30000 m or less, and the first sample cut-out portion within 2 m from the end of film winding, and the final within 2 m from the start of film winding When the sample cutout portion is provided at intervals of about 100 m from the first sample cutout portion, the following requirements (1) to (3) are satisfied.
(1) For each sample cut out from each cutout part, when measuring the maximum boiling water shrinkage, which is the maximum value of the boiling water shrinkage in all directions, the average is the average value of the maximum boiling water shrinkage The boiling water shrinkage is 2% to 6%, and the variation rate of the maximum boiling water shrinkage of all the samples is within a range of ± 2% to ± 10% with respect to the average boiling water shrinkage (2) For each sample cut out from each cut-out part, the boiling water shrinkage direction difference, which is the absolute value of the difference between the boiling water shrinkage rate in the +45 degree direction with respect to the longitudinal direction and the boiling water shrinkage ratio in the −45 degree direction with respect to the longitudinal direction, is obtained. The average boiling water shrinkage direction difference, which is the average value of the boiling water shrinkage direction differences, is 1.5% or less, and the variation rate of the boiling water shrinkage direction difference of all the samples is the average boiling water shrinkage. Within ± 2% to ± 10% of rate direction difference There (3) rate of change in thickness over the entire length in the longitudinal direction of the wound roll is in the range of from ± 2% ~ ± 10% relative to the average thickness

  The configuration of the invention described in claim 2 is that, in the invention described in claim 1, when the refractive index in the thickness direction is measured for each sample cut out from each cutout portion, the average of those refractive indexes is measured. The average refractive index as a value is 1.500 or more and 1.520 or less, and the variation rate of the refractive index of all the samples is within a range of ± 2% with respect to the average refractive index.

The structure of the invention described in claim 3 is the invention described in claim 1, wherein the adhesion-modified layer is formed by applying a coating agent containing a copolymerized polyester aqueous dispersion, A copolymerizable polyester aqueous dispersion comprising grafted polyester particles and an aqueous solvent, wherein the grafted polyester comprises a polyester main chain and a radical polymerizable monomer having a hydrophilic group. A half-width of a ¹³ C-NMR signal of carbonyl carbon derived from the polyester main chain of the grafted polyester particle, wherein the grafted polyester particle has an average particle size of 500 nm or less Is 300 Hz or more.

  The structure of the invention described in claim 4 is that, in the invention described in claim 1, the main component of the polyamide constituting the polyamide resin film is nylon 6.

  The structure of the invention described in claim 5 is that, in the invention described in claim 1, a polyamide resin film formed from a mixture of two or more different polyamide resins is wound up. .

  The structure of the invention described in claim 6 is that, in the invention described in claim 1, the wound polyamide resin film is laminated with the polyolefin resin film.

  The structure of the invention described in claim 7 is the non-oriented structure obtained in the invention described in claim 1 by extruding the melted polyamide-based resin from the T-die and bringing it into contact with a metal roll and cooling it. That is, a polyamide-based resin film obtained by biaxially stretching a sheet-like material is wound up.

  The structure of the invention described in claim 8 is that, in the invention described in claim 1, the polyamide resin film stretched by the tenter stretching method is wound.

  The structure of the invention described in claim 9 is that in the invention described in claim 1, the polyamide-based resin film that has been sequentially biaxially stretched is wound.

  The structure of the invention described in claim 10 is that, in the invention described in claim 1, a polyamide-based resin film stretched biaxially in the vertical direction and the horizontal direction is wound.

  The structure of the invention described in claim 11 is the invention described in claim 1, wherein the sheet-like material made of a substantially unoriented polyamide resin is more than the glass transition temperature of the polyamide resin + 20 ° C. A polyamide-based resin film that has been stretched in the longitudinal direction in at least two stages so as to obtain a magnification of 3 times or more at a high temperature and then wound in the transverse direction so as to obtain a magnification of 3 or more times. There is to be.

  The structure of the invention described in claim 12 is that, in the invention described in claim 1, the polyamide-based resin film that is heat-set after the final stretching treatment is wound.

  The structure of the invention described in claim 13 is that, in the invention described in claim 1, the polyamide resin film which has been subjected to relaxation treatment after heat setting is wound up.

  The structure of the invention described in claim 14 is the same as that of the invention described in claim 1, but in the polyamide-based resin film wound up, a lubricant, an anti-blocking agent, a heat stabilizer, an antioxidant, and an antistatic agent. In addition, at least one of a light resistance agent and an impact resistance improvement agent is added.

  The structure of the invention described in claim 15 is that, in the invention described in claim 1, inorganic particles are added to the wound polyamide resin film.

  The structure of the invention described in claim 16 is that, in the invention described in claim 1, the inorganic particles are silica particles having an average particle diameter of 0.5 to 5.0 μm.

  The structure of the invention described in claim 17 is that, in the invention described in claim 1, higher fatty acid is added to the wound polyamide-based resin film.

The structure of the invention described in claim 18 is a manufacturing method for manufacturing the polyamide-based resin laminated film roll described in claim 1, wherein the film is formed by melting and extruding the polyamide-based resin chip. A biaxial stretching process for biaxially stretching the unstretched film obtained in the film forming process in the longitudinal direction and the transverse direction, and a laminating process for laminating an adhesion modified layer layer on at least one surface of the biaxially stretched film And satisfy the following requirements (a) to (e).
(A) The biaxial stretching step involves stretching in the transverse direction after stretching in two stages in the longitudinal direction, and the first-stage stretching ratio in the two-stage stretching in the longitudinal direction is determined from the second-stage stretching ratio. (B) The film forming step mixes a chip made of a polyamide resin having the largest amount of use with one or more other polyamide resin chips having a composition different from that of the polyamide resin chip. After that, the polyamide resin chip to be used is melt-extruded, and the shape of each polyamide resin chip used is an elliptical cylinder having an elliptical cross section having a major axis and a minor axis, and the polyamide resin chip having the largest amount of use Other than polyamide resin chips, the average major axis, average minor axis, and average chip length of the polyamide resin chips with the largest use amount are ± 2 respectively. (C) an extruder provided with a funnel-shaped hopper as a raw material chip supply unit, being adjusted to have an average major axis, an average minor axis and an average chip length included in the range of And a step of melt extrusion using the hopper, the inclination angle of the hopper is adjusted to 65 degrees or more, and the moisture content of the polyamide resin chip before being supplied to the hopper is adjusted to 800 ppm or more and 1000 ppm or less. The temperature of the polyamide resin chip before being supplied to the hopper is adjusted to 80 ° C. or higher. (D) The film forming step uses the molten resin extruded from the extruder as a cooling roll. In addition to the step of cooling by winding, in the cooling step, the part that contacts the surface of the molten resin and the cooling roll, (E) The lamination step is performed to reduce the coating amount of the final adhesion-modified layer to 0.01 to 1.00 g / m by sucking in the direction opposite to the winding direction by the suction device over the entire width of the molten resin. ² to apply a coating solution for forming an adhesion-modified layer

  The structure of the invention described in claim 19 includes the preheating step executed before the longitudinal stretching step and the heat treatment step executed after the longitudinal stretching step in the invention described in claim 18. The fluctuation range of the surface temperature of the film at an arbitrary point in the longitudinal stretching step, the preheating step, and the heat treatment step is adjusted within the range of the average temperature ± 1 ° C. over the entire length of the film. .

The structure of the invention described in claim 20 is a polyamide system in which an adhesion modified layer made of a copolyester is laminated on at least one side, the width is 0.2 m or more and 3.0 m or less, and the length is 300 m or more and 30000 m or less. A polyamide-based resin laminated film roll formed by winding up a resin film, wherein a first sample cut-out portion is provided within 2 m from the end of winding of the film, and a final cut-out portion is provided within 2 m from the start of film winding. When the sample cut-out portion is provided every about 100 m from the first sample cut-out portion, the following requirement (4) is satisfied.
(4) For each sample cut out from each cutout portion, when the peel strength when a polyolefin film is laminated is determined, the average peel strength, which is the average value of those peel strengths, is 500 g / 15 mm width or more. The variation rate of the peel strength of all the samples is within a range of ± 5% to ± 30% with respect to the average peel strength.

The structure of the invention described in claim 21 is a polyamide system in which an adhesion modified layer made of a copolyester is laminated on at least one side, the width is 0.2 m or more and 3.0 m or less, and the length is 300 m or more and 30000 m or less. A polyamide-based resin laminated film roll formed by winding up a resin film, wherein a first sample cut-out portion is provided within 2 m from the end of winding of the film, and a final cut-out portion is provided within 2 m from the start of film winding. When the sample cut-out portion is provided every about 100 m from the first sample cut-out portion, the following requirement (5) is satisfied.
(5) For each sample cut out from each cut-out part, when the hot water peel strength after 30 minutes immersion in 90 ° C. hot water when a polyolefin film is laminated is obtained, the hot water peel strength The average hot water peel strength of 150 g / 15 mm width or more, and the variation rate of the hot water peel strength of all the samples is ± 5% to ± 30% with respect to the average hot water peel strength. Is in range

  Therefore, the polyamide-based resin laminated film roll of the present invention has a very high peel strength between the polyamide-based resin film as the base film and the coating layer, and is highly uniform. Therefore, according to the film roll of the present invention, a packaging bag suitable for applications such as retort food can be manufactured with high productivity, homogeneously and with a high yield. Furthermore, according to the polyamide-based resin laminated film roll of the present invention, it is possible to carry out the bag making process by lamination smoothly with almost no trouble, and it is possible to efficiently obtain a package having no S-curl. Further, in post-processing such as bag making processing, a processed product can be obtained with a high yield. In addition, if the polyamide film roll of the present invention is used, the bag for food packaging after the bag making process by lamination becomes tough and excellent in pinhole resistance.

  In addition, since the polyamide-based resin laminated film constituting the polyamide-based resin laminated film roll of the present invention has an adhesion modified layer made of a copolymerized polyester formed on at least one surface of the polyamide film substrate, Excellent water and water resistant adhesion to sealant materials laminated by extrusion lamination. Therefore, the packaging bag formed using the film roll of the present invention has very few broken bags even when retort treatment or boiling water treatment is performed, and thus can be widely used as a packaging bag for water-containing foods and medicines.

  When the polyamide film roll of the present invention is cut out by the method described later, the maximum boiling water shrinkage rate, which is the maximum value of the boiling water shrinkage rate in all directions, is measured for all the samples. The average boiling water shrinkage, which is the average value of the maximum boiling water shrinkage, is adjusted to be 2% or more and 6% or less.

  The polyamide film roll of the present invention has a boiling water shrinkage rate in the +45 degree direction with respect to the longitudinal direction and a boiling water shrinkage in the -45 degree direction with respect to the longitudinal direction for all the samples when the samples are cut out by the method described later. When the boiling water shrinkage direction difference, which is the absolute value of the difference from the rate, is determined, the average boiling water shrinkage direction difference, which is the average value of the boiling water shrinkage direction differences, is adjusted to be 1.5% or less. ing.

  In the cutting of the sample in the present invention, first, the first sample cutting portion is provided within 2 m from the end of winding of the film, and the final cutting portion is provided within 2 m from the beginning of winding of the film. A sample cut-out section is provided every about 100 m. Note that “about every 100 m” means that the sample may be cut out at about 100 m ± 1 m.

  More specifically, the cutting of the above sample will be described. For example, when a polyamide-based film having a length of 498 m is wound around a roll, the first sample (1) is taken within 2 m from the end of winding of the film. cut out. For convenience, the sample is cut out in a rectangular shape so as to have a side along the longitudinal direction of the film and a side along the direction orthogonal to the longitudinal direction (not cut diagonally). Subsequently, the second sample (2) is cut away from the cut portion at a distance of 100 m from the winding start side. In the same manner, the third sample (3) is separated to the winding start side of 200 m, the fourth sample (4) is separated to the winding start side of 300 m, and the fifth sample is separated to the winding start side of 400 m. Cut out (5). When the sample is cut out in this way, the remainder becomes shorter than 100 m, so the sixth (final) sample (6) cuts out any portion within 2 m from the start of film winding. For each of the cut samples, the boiling water shrinkage rate (hereinafter referred to as BS), the maximum boiling water shrinkage rate (hereinafter referred to as BSx), the average boiling water shrinkage rate (hereinafter referred to as BSax), and the boiling water shrinkage direction in the following manner. A difference (hereinafter referred to as BSd) and an average boiling water shrinkage direction difference (hereinafter referred to as BSad) are measured.

[Measuring method of boiling water shrinkage (BS), maximum boiling water shrinkage (BSx), average boiling water shrinkage (BSax), boiling water shrinkage direction difference (BSd), average boiling water shrinkage direction difference (BSad)]
The biaxially oriented polyamide-based resin film cut out from each cut-out portion of the polyamide-based resin film roll is cut into a square shape and left in an atmosphere of 23 ° C. and 65% RH for 2 hours or more. A circle (about 20 cm in diameter) centered on the center of this sample is drawn, and a straight line passing through the center of the circle in the direction of 0 to 165 ° clockwise at 15 ° intervals, with the vertical direction (film drawing direction) being 0 °. Pull, measure the diameter in each direction, and make it the length before processing. The cut sample was then heat-treated in boiling water for 30 minutes, then removed and wiped off the moisture adhering to the surface, air-dried, and left in an atmosphere of 23 ° C. and 65% RH for 2 hours or more, as described above. The length of the straight line drawn in each diametric direction is measured and set as the length after treatment. BS (boiling water shrinkage), BSx (maximum boiling water shrinkage), BSax (average boiling water shrinkage), BSd (boiling water shrinkage direction difference) and BSad (average boiling water shrinkage direction difference) are calculated.
BS = [(length before processing−length after processing) / length before processing] × 100 (%)... 1
BSx = Maximum shrinkage rate (%) measured in 0 to 165 ° direction at 15 ° intervals 2
BSax = sum of BSx of all samples / number of samples 3
BSd = | (BS in 45 ° direction) − (BS in 135 ° direction) |
BSad = sum of BSd of all samples / number of samples 5

  The value of BSx of the polyamide film constituting the polyamide film roll is the heat resistance when the biaxially oriented polyamide resin film is formed into a bag shape and subjected to hot water treatment (also referred to as laminate strength or heat resistant laminate strength). This is important for enhancing the toughness and pinhole resistance of the film itself. If the BSx value is less than 2%, the toughness and pinhole resistance will be insufficient, whereas it will exceed 6%. In such a case, it is not preferable because the laminate becomes defective or the heat-resistant laminate strength at the time of hot water treatment becomes insufficient. The range of BSx that is more preferable for enhancing toughness, pinhole resistance, laminating properties, and heat-resistant laminating strength is 3.5 to 5.0%.

  In addition, the BSd value of the polyamide film constituting the polyamide film roll has a great influence on the curling phenomenon that occurs during boiling water treatment, and the larger the BSd value, the easier the bag will bend and the curling becomes remarkable. If it is suppressed to 1.5% or less, more preferably 1.2% or less, the warping of the bag during boiling water treatment is suppressed as much as possible, and the occurrence of the S-curl phenomenon can be prevented.

  Further, in the polyamide film roll of the present invention, the variation rate of the maximum boiling water shrinkage (BSx) of all the cut out samples is ± 2% to ± 10% (± 2% or more ±) of the average boiling water shrinkage (BSa). 10% or less) is required to be adjusted. Here, the variation rate of the maximum boiling water shrinkage (BSx) of all the samples is the maximum / minimum of the maximum boiling water shrinkage (BSx) of all the samples, and the average boiling water shrinkage of those maximum / minimum. It means the ratio of the difference with respect to the average boiling water shrinkage when the difference between the one with the larger difference between the ratio and the average boiling water shrinkage is obtained.

  That is, in the polyamide film roll of the present invention, when the boiling water shrinkage of samples (1) to (6) is Xn (n = 1 to 6), the maximum value Xmax of Xn and the average boiling water shrinkage (BSax) ) And the difference between the minimum value Xmin and the average boiling water shrinkage (BSax) must be within ± 10%, in other words, | BSax− Xn | (where || indicates an absolute value) is required to be 10% or less.

  The polyamide film roll of the present invention preferably has a variation rate of the maximum boiling water shrinkage (BSx) of all the cut out samples within a range of ± 9% of the average boiling water shrinkage (BSa), and ± 8 % Is more preferable, and it is more preferable that it is within ± 7%.

  In addition, the polyamide film roll of the present invention is preferably as small as the variation rate of the maximum boiling water shrinkage (BSx) of all the cut out samples, but the lower limit of the variation rate is about 2% considering the measurement accuracy. I think it is the limit.

  In the polyamide film roll of the present invention, the fluctuation rate of the boiling water shrinkage direction difference (BSd) of all the cut out samples is ± 2% to ± 10% (± 2) of the average boiling water shrinkage direction difference (BSad). % Or more and ± 10% or less) is required to be adjusted. Here, the fluctuation rate of the boiling water shrinkage direction difference (BSd) of all the samples is the maximum / minimum in the boiling water shrinkage direction difference (BSd) of all the samples, and the average of these maximum / minimum values. When the difference between the larger difference between the boiling water shrinkage direction difference and the average boiling water shrinkage direction difference is obtained, it means the ratio of the difference to the average boiling water shrinkage direction difference.

  That is, in the polyamide film roll of the present invention, when the boiling water shrinkage direction difference of the samples (1) to (6) is Yn (n = 1 to 6), the maximum value Ymax of Yn and the average boiling water shrinkage rate. That is, the difference between the direction difference (BSad) and the difference between the minimum value Ymin and the average boiling water shrinkage direction difference (BSad) must be within ± 10%. In other words, | BSad−Yn | (where || indicates an absolute value) is required to be 10% or less.

  In the polyamide film roll of the present invention, it is preferable that the variation rate of the boiling water shrinkage direction difference (BSd) of all the cut out samples is within ± 9% of the average boiling water shrinkage direction difference (BSad). , More preferably within the range of ± 8%, and even more preferably within the range of ± 7%.

  In addition, the polyamide film roll of the present invention is preferable as the fluctuation rate of the boiling water shrinkage direction difference (BSd) of all the cut out samples is smaller, but the lower limit of the fluctuation rate is about 2% in consideration of measurement accuracy. Is the limit.

  In the polyamide film roll of the present invention, the variation rate of the thickness over the entire length in the longitudinal direction is within a range of ± 2% to ± 10% (± 2% to ± 10%) with respect to the average thickness. It is necessary to be adjusted to. Here, the variation rate of the thickness over the entire length in the longitudinal direction is the maximum / minimum of the thickness over the entire length in the longitudinal direction, and the difference between the average thickness of the maximum / minimum average thickness and the average thickness It means the ratio of the difference to the average thickness when the difference is obtained.

  That is, in the polyamide film roll of the present invention, the difference between the maximum value Tmax of the thickness over the entire length in the longitudinal direction and the average thickness (average thickness Ta over the entire length in the longitudinal direction), the minimum value Tmin, and the average thickness (Ta) The difference between the two is required to be within ± 10%.

  In the polyamide film roll of the present invention, the variation rate of the thickness over the entire length in the longitudinal direction is preferably within ± 8% of the average thickness (Ta), and more preferably within ± 6%. .

  In addition, the polyamide-based film roll of the present invention is preferable as the variation rate of the thickness over the entire length in the longitudinal direction is smaller, but the lower limit of the variation rate is considered to be about 2% from the viewpoint of the performance of the film forming apparatus. ing.

  In addition, the polyamide-based resin laminated film of the present invention has an average peel strength that is an average value of peel strengths of all cut out samples (measured by the measuring method described in paragraph No. 0209) of 500 g / 15 mm width or more. It is necessary that there is a width of 750 g / 15 mm or more. If the average peel strength is less than 500 g / 15 mm width, the bag opening after the bag making process is likely to burst, which is not preferable.

  In the polyamide film roll of the present invention, the variation rate of the peel strength of all cut out samples is within a range of ± 5% to ± 30% (± 5% to ± 30%) of the average peel strength. It is preferable to adjust so. Here, the variation rate of peel strength of all samples is the maximum / minimum of the peel strengths of all samples, and the difference between the average peel strength of the maximum / minimum and the average peel strength Is the ratio of the difference to the average peel strength when the difference is obtained.

  That is, in the polyamide film roll of the present invention, when the peel strength of the samples (1) to (6) is Sn (n = 1 to 6), the maximum value Smax of Sn and the average peel strength (Sa) And the difference between the minimum value Smin and the average peel strength is preferably within ± 30%. In other words, | Sa−Sn | (where || It is preferable that all of them are 30% or less.

  In the polyamide film roll of the present invention, the variation rate of the peel strength of all the cut out samples is preferably within ± 20% of the average peel strength, and more preferably within ± 15%. . In addition, the polyamide film roll of the present invention is preferable as the variation rate of the peel strength of all the cut out samples is small, but the lower limit of the variation rate is considered to be about 5% in consideration of measurement accuracy. ing.

  Furthermore, the polyamide-based resin laminated film of the present invention has an average hot water peel strength of 150 g / hr, which is an average value of the hot water peel strength (obtained by the measuring method described in paragraph No. 0210) of all the cut out samples. The width is preferably 15 mm or more, and more preferably 250 g / 15 mm or more. An average hot water peel strength of less than 150 g / 15 mm width is not preferable because the opening of the bag after the bag-making process for retort foods tends to burst in hot water.

  The polyamide film roll of the present invention has a variation rate of hot water peel strength of all cut out samples of ± 5% to ± 30% (± 5% to ± 30%) of the average hot water peel strength. It is preferable to adjust to be within the range. Here, the variation rate of the hot water peel strength of all the samples is the maximum / minimum of the hot water peel strength of all the samples, and the difference between the average hot water peel strength of the maximum and minimum When the difference between the larger one and the average hot water peel strength is determined, it means the ratio of the difference to the average hot water peel strength.

  That is, in the polyamide film roll of the present invention, when the hot water peel strength of the samples (1) to (6) is Hn (n = 1 to 6), the maximum value Hmax of Hn and the average hot water peel strength. (Ha), and the difference between the minimum value Hmin and the average hot water peel strength is preferably within ± 30%, in other words, | Ha−Hn | ( Note that || indicates an absolute value) is preferably 30% or less.

  In the polyamide film roll of the present invention, the variation rate of the hot water peel strength of all the cut out samples is preferably within ± 20% of the average hot water peel strength, and within ± 15%. More preferably. In addition, the polyamide film roll of the present invention is preferable as the variation rate of the hot water peeling strength of all the cut out samples is smaller, but the lower limit of the variation rate is about 5% in consideration of measurement accuracy. I believe.

Furthermore, the polyamide film roll of the present invention is an average which is an average value of the refractive indexes when the refractive index (Nz) in the thickness direction is obtained for all the samples when the samples are cut out by the above method. It is preferable to adjust the refractive index (Nza) to be 1.500 or more and 1.520 or less. The average refractive index is calculated by the following formula 6.
Nza = total Nz of all samples / number of samples 6

  The Nz value of the polyamide film constituting the polyamide film roll has a great influence on the film quality such as the laminate strength and thickness unevenness. Therefore, the requirement that the average refractive index is 1.500 or more and 1.520 or less is an indispensable requirement when the biaxially oriented polyamide resin film is laminated with the polyolefin resin film. When Nz is less than 1.500, the laminate strength with the polyolefin resin film or the like becomes insufficient, and peeling between the laminate base material is likely to occur due to boiling water treatment after bag making. On the other hand, this Nz gradually decreases in the process of biaxially stretching an unstretched polyamide resin film. In other words, Nz can also be considered as one of the indices of stretching, and a large Nz indicates that stretching is insufficient. If Nz exceeds 1.520, it is due to insufficient biaxial stretching. Thick spots and the like appear remarkably, and satisfactory film quality cannot be obtained. Considering both the laminate strength and the film quality, a particularly preferable range of Nz is in the range of 1.507 to 1.516.

  In the polyamide film roll of the present invention, the variation rate of the refractive index (Nz) of all the cut out samples is within ± 2% with respect to the average value of the refractive indexes (hereinafter referred to as the average refractive index). It is preferable to adjust so that it may become a range. Here, the variation rate of the refractive index (Nz) of all the samples is the maximum / minimum of the refractive indexes (Nz) of all the samples, and the difference between the average refractive index of the maximum / minimum values. When the difference between the larger one and the average refractive index is obtained, it means the ratio of the difference to the average refractive index.

  That is, in the polyamide film roll of the present invention, when the refractive indexes of the samples (1) to (6) are Nz1 to Nz6, the difference between the maximum value Nzmax of Nz1 to Nz6 and the average refractive index is Nz1 to Nz1. That is, it is preferable that the difference between the minimum value Nzmin of Nz6 and the average refractive index is within ± 2%. In other words, | average refractive index−Nz1 | ˜ | average refractive index−Nz6 | Is preferably 2% or less. In the polyamide film roll of the present invention, it is more preferable that the variation rate of the refractive index (Nz) of all the cut out samples is within ± 1% of the average refractive index.

  In addition, the polyamide-based film roll of the present invention is preferably as small as the variation rate of the refractive index (Nz) of all the cut out samples, but the lower limit of the variation rate is 0.1 in terms of measurement accuracy and mechanical accuracy. % Is considered the limit.

  As described above, the maximum boiling water shrinkage rate and boiling water shrinkage direction difference in one polyamide film roll are adjusted to values within a predetermined range, and the fluctuations in the maximum boiling water shrinkage rate and boiling water shrinkage direction difference are reduced. By doing so, it is possible to prevent deterioration of the appearance in bag making and laminating, and it is possible to process smoothly with a high yield.

  Examples of the polyamide resin used in the present invention include nylon 6 using ε-caprolactam as a main raw material. Examples of other polyamide resins include polyamide resins obtained by polycondensation of lactams having three or more members, ω-amino acids, dibasic acids and diamines. Specifically, as lactams, in addition to the aforementioned ε-caprolactam, enantolactam, capryllactam, lauryllactam, and ω-amino acids include 6-aminocaproic acid, 7-aminoheptanoic acid, 9- Examples include aminononanoic acid and 11-aminoundecanoic acid. Dibasic acids include adipic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecadioic acid, hexadecadioic acid, eicosandioic acid, eicosadienedioic acid, 2 2,4-trimethyladipic acid, terephthalic acid, isophthalic acid, 2,6-naphthalenedicarboxylic acid, and xylylenedicarboxylic acid. Furthermore, as diamines, ethylenediamine, trimethylenediamine, tetramethylenediamine, hexamethylenediamine, pentamethylenediamine, undecamethylenediamine, 2,2,4 (or 2,4,4) -trimethylhexamethylenediamine, cyclohexane Examples thereof include diamine, bis- (4,4′-aminocyclohexyl) methane, and metaxylylenediamine. And polymers obtained by polycondensation of these or copolymers thereof, such as nylon 6, 7, 11, 12, 6.6, 6.9, 6.11, 6.12, 6T, 6I, MXD6 (Metaxylene dipanamid 6), 6 / 6.6, 6/12, 6 / 6T, 6 / 6I, 6 / MXD6, and the like can be used. In addition, when the polyamide film roll of the present invention is produced, the above polyamide resins can be used alone or in admixture of two or more.

  Of the polyamide-based resins, those having a relative viscosity in the range of 2.0 to 3.5 are particularly preferable in the present invention. The relative viscosity of the polyamide-based resin affects the toughness and spreadability of the resulting biaxially stretched film. If the relative viscosity is less than 2.0, the impact strength tends to be insufficient. This is because, if it exceeds 3.5, the biaxial stretchability tends to deteriorate with increasing stretching stress. In addition, the relative viscosity in this invention means the value at the time of measuring at 25 degreeC using the solution which melt | dissolved 0.5g of polymers in 50 ml of 97.5% sulfuric acid.

  Next, the preferable manufacturing method for obtaining the polyamide-type resin film roll of this invention is demonstrated. The polyamide-based resin film roll of the present invention is formed into a roll after biaxially stretching an unstretched film obtained by melting and extruding a raw material polyamide resin chip in the longitudinal direction (longitudinal direction) and the transverse direction (width direction). Manufactured by winding. Moreover, it is necessary to laminate | stack an adhesion modification layer on a polyamide-type resin film before and during biaxial stretching, but it is performed after extending | stretching the lamination | stacking of the said adhesion modification layer to the vertical direction (longitudinal direction). preferable. In addition, the lamination | stacking method of an adhesion modification layer is mentioned later.

  As a result of studying fluctuations and variations in physical properties such as vertical unevenness of the filum roll (thickness unevenness over the entire length of the firoom roll) and boiling water shrinkage rate, the present inventors have found such vertical thickness unevenness and physical properties. It has been found that the fluctuations and variations are greatly influenced mainly by various factors in the casting process in which a molten resin is converted into an unstretched film. That is, if the temperature of the resin when supplied to a funnel-shaped popper directly connected to the extruder (hereinafter simply referred to as a hopper) is low or the moisture content of the resin supplied to the hopper is high, the thickness in the longitudinal direction of the unstretched film It was found that the spots became larger, and the fluctuations and variations in physical properties of the biaxially stretched film increased. In addition, when the resin extruded from the T die is wound around a metal roll, even if the contact point between the resin and the metal roll is disturbed, the thickness unevenness in the longitudinal direction in the unstretched film becomes large, and the physical properties in the biaxially stretched film It was found that the fluctuation and variation of Furthermore, it was also found that if the stretching conditions in the biaxial stretching process are inappropriate, the thickness unevenness in the longitudinal direction of the unstretched film is amplified, which promotes fluctuations and variations in physical properties.

Furthermore, as a result of intensive studies based on the above facts, the present inventors have found out that it is possible to obtain a film roll with little fluctuation in physical properties by taking the following means when manufacturing the film roll. It was.
(1) Uniformity of resin chip shape (2) Optimization of hopper shape (3) Reduction of moisture content when resin chip is dried (4) Temperature retention when resin is supplied to hopper (5) Molten resin to metal roll Suction at the time of contact (6) Optimization of stretching conditions Hereinafter, each of the above-described means will be sequentially described.

(1) Uniformization of resin chip shape In the production of the film roll of the present invention, when adopting a blending method, a plurality of raw material polyamide resin chips having different compositions are blended in a hopper, then melt-kneaded and extruded. Extrude from machine and film. For example, when there are three types of polyamide as the raw material, the respective polyamide resin chips are supplied to three hoppers in a continuous or intermittent manner, and finally through the buffer hopper as needed, finally before the extruder Alternatively, while mixing three types of polyamide resin chips in a hopper directly above (hereinafter referred to as “final hopper”), raw material chips are quantitatively supplied to the extruder according to the extrusion amount of the extruder to form a film.

  However, depending on the capacity or shape of the final hopper, when the amount of chips in the final hopper is large and the remaining amount of chips in the final hopper is small, the material segregation phenomenon, that is, from the final hopper to the extruder. A phenomenon occurs in which the composition of the supplied chip is different. Further, such segregation phenomenon appears particularly prominent when the shape or specific gravity of the chip is different. Further, due to such segregation phenomenon, when a long film is produced, the maximum boiling water shrinkage rate, the boiling water shrinkage direction difference, the film thickness, and the refractive index in the thickness direction vary.

  That is, if there is a difference in the size of the chips, when the mixture of chips falls in the final hopper, small chips tend to fall first, so if the remaining amount of chips in the final hopper decreases, This increases the ratio of this, which causes segregation of raw materials. Therefore, in order to obtain a film roll with little variation in physical properties, it is necessary to match the shapes of a plurality of types of polyamide resin chips to be used to suppress the phenomenon of raw material segregation in the final hopper.

  Polyamide raw material chips are usually formed in a molten state after polymerization in the form of strands from a polymerization apparatus, immediately cooled with water, and then cut with a strand cutter. For this reason, the polyamide chip has an elliptical column shape with an elliptical cross section. Here, as a result of examining the relationship between the shape of the polymer chip and the raw material segregation, the average major axis (mm), the average minor axis (mm) of the cross-sectional ellipse of the other polyamide chips mixed with the polyamide chip with the largest amount of use, The average tip length (mm) is ± 20% relative to the average major axis (mm), average minor axis (mm), and average tip length (mm) of the cross-sectional ellipse of the polyamide material chip with the largest use amount, respectively. The raw material segregation can be reduced by adjusting within the above range. The average major axis, average minor axis, and average tip length of the elliptical cross section of the polyamide chip other than the polyamide chip with the largest amount of use are respectively shown in FIG. Adjustment to a range within ± 15% with respect to the diameter and average chip length is more preferable because the effect of preventing segregation becomes extremely remarkable.

(2) Optimizing the hopper shape By using a funnel-shaped hopper as the final hopper and making its inclination angle 65 ° or more, large chips can be easily dropped as well as small chips. Since it descends while maintaining a horizontal plane, it is effective in reducing raw material segregation. A more preferable inclination angle is 70 ° or more. The inclination angle of the hopper is an angle between the funnel-shaped hypotenuse and the horizontal line segment. A plurality of hoppers may be used upstream of the final hopper. In this case, in any hopper, the inclination angle needs to be 65 ° or more, and more preferably 70 ° or more.

  It is also preferable to reduce the ratio of the fine powder generated due to the cutting of the raw material chips used in order to suppress fluctuations in the boiling water shrinkage rate. Since the fine powder promotes the occurrence of raw material segregation, it is preferable to remove the fine powder generated in the process and reduce the ratio of the fine powder contained in the hopper. The ratio of the fine powder contained is preferably within 1% by weight and more preferably within 0.5% by weight throughout the entire process until the raw material chips enter the extruder. As a specific method for reducing the fine powder ratio, the fine powder is removed by passing a sieve at the time of chip formation with a strand cutter or by passing a cyclone air filter when the raw material chips are air-fed. The method of doing can be mentioned.

  In addition, as a means for reducing raw material segregation in the hopper, it is also a preferable means to optimize the capacity of the hopper used. Here, the proper capacity of the hopper is in the range of 15 to 120% by weight with respect to the discharge amount per hour of the extruder, and 20 to 100% by weight with respect to the discharge amount per hour of the extruder. It is more preferable that it is within the range.

  As a method of mixing two or more kinds of polyamide raw material chips having different compositions, a method of mixing while continuously feeding each raw material to the extruder with a hopper (final hopper) directly above the extruder is most preferable. It is also possible to feed a final hopper and an extruder through several intermediate hoppers (buffer hoppers) after previously mixing a raw material chip size controlled within the aforementioned range. When mixing multiple types of raw materials, use a method of mixing raw materials chips continuously while quantitatively supplying multiple types of raw materials into a hopper, or using a blender, paddle dryer, etc. However, when using the latter, it is preferable to reduce the raw material chip size so that the raw material segregation does not occur when the mixture is discharged.

(3) Reduction of moisture content during resin chip drying Chips supplied into the hopper are usually heated by a device such as a blender to reduce moisture. When drying such a chip, in the production of a polyester film roll or a polypropylene film roll, it is generally considered that the lower the moisture content during drying, the less hydrolysis in the extrusion process and the better the film roll is obtained. ing. However, as a result of studies by the present inventors, in the production of a polyamide-based resin film roll, it is difficult to stretch simply by lowering the moisture content during drying, and a film roll having uniform physical properties can be obtained. First, it was found that a film roll with uniform physical properties can be obtained by controlling the moisture content within a predetermined range and securing a certain amount of moisture so as to be appropriately plasticized without being hydrolyzed in the extrusion process. . That is, in order to obtain the film roll of the present invention, it is necessary to control the moisture content of the chip to 800 ppm or more and 1000 ppm or less. When the moisture content of the chip exceeds 1000 ppm, hydrolysis is promoted when it is melted, the viscosity is lowered, the thickness unevenness in the longitudinal direction of the unstretched film is deteriorated, and the thickness unevenness in the longitudinal direction of the biaxially stretched film is deteriorated. Increase, fluctuations in physical properties and variations. On the contrary, if the moisture content of the chip is less than 800 ppm, the viscosity when melted becomes too high, and the film-forming property (easy to stretch) deteriorates. In addition, the optimal moisture content of the chip | tip supplied into a hopper is 850 ppm or more and 950 ppm or less.

(4) Maintaining temperature when resin is supplied to the hopper As described above, even when the moisture content of the chip is adjusted to 800 ppm or more and 1000 ppm or less, the chip after heating and drying is allowed to stand until the temperature reaches room temperature (room temperature). When it is supplied to the hopper after being lowered, a film roll with uniform physical properties cannot be obtained. That is, in order to obtain the film roll of the present invention, it is necessary to supply the chips heated and dried by a blender or the like to the hopper while keeping the temperature high. Specifically, the chips dried by heating with a blender need to be supplied to the hopper while being maintained at 80 ° C. or higher, and more preferably supplied to the hopper while being maintained at 90 ° C. or higher. When the temperature of the chip supplied to the hopper is lower than 80 ° C., the resin bite becomes worse, causing vertical thickness unevenness, physical property fluctuations and variations, and the film roll of the present invention cannot be obtained. In addition, when drying a chip | tip with apparatuses, such as a blender, it is necessary to adjust drying temperature to 150 degrees C or less. If the drying temperature exceeds 150 ° C., hydrolysis may occur during drying, which is not preferable. In addition, when the temperature of the chip heat-dried by the blender falls below 80 ° C., it is necessary to reheat the chip to 80 ° C. or higher and supply it to the hopper.

(5) Suction when the molten resin is brought into contact with a metal roll When an unstretched film is obtained by melting and extruding a chip, the chip is melted at a temperature of 200 to 300 ° C. by an extruder and extruded from a T die. After forming (that is, casting) into a film shape (sheet shape), it is rapidly cooled by a method of winding it around a cooling roll such as a metal roll cooled to a predetermined temperature. In addition, from the viewpoint of vertical thickness variation, physical property fluctuations, and variations, a preferable melt extrusion temperature is 240 ° C. to 290 ° C. In order to obtain the film roll of the present invention, when the molten resin is wound around the metal roll, the air gap (that is, the vertical distance from the exit of the T die lip to the chill roll surface) is adjusted to 20 to 60 mm, Using a suction device such as a vacuum box (vacuum chamber) with a wide suction port, the part that contacts the surface of the molten resin and the cooling roll is sucked across the entire width of the molten resin in the direction opposite to the winding direction. By doing so, it is preferable that the molten resin is forcibly adhered to the metal roll. In this case, the suction air speed at the suction port is set to 2.0 to 7.0 m / sec. Need to be adjusted to 2.5 to 5.5 m / sec. It is more preferable to adjust to. Furthermore, the vacuum box may have a series of suction ports, but the suction ports are divided into a predetermined number of sections in the lateral direction in order to facilitate adjustment of the suction air velocity at the suction ports. It is preferable that the suction air speed can be adjusted for each section. Further, when the casting speed is increased, an accompanying flow is generated with the rotation of the metal roll, and the adhesion of the molten resin to the metal roll is hindered. In order to improve the degree of adhesion of the metal roll to the metal roll, the upstream side adjacent to the suction device (on the side opposite to the rotation direction of the metal roll with respect to the suction device) It is preferable to block the accompanying flow. Furthermore, in order to obtain the film roll of the present invention, it is necessary to suppress the variation in the suction wind speed of the vacuum box within ± 20% of the average suction wind speed (set value), and more preferably within ± 10%. . In addition, it is preferable to adjust the suction force by providing a filter in the vacuum box and feeding back the differential pressure before and after the filter so that the suction wind speed of the vacuum box does not fluctuate due to oligomer dust or the like.

  Moreover, in order to obtain the film roll of the present invention, when the molten resin is wound around the cooling roll, a DC negative charge of 90 to 105 mA is applied to the molten resin sheet at 2 to 15 kv from the needle electrode, It is necessary to continuously contact and quench the metal roll while glow discharge. In this case, it is preferable to adjust the DC negative charge to be applied in the range of 7 to 14 kv because vertical thickness variation, physical property fluctuations and variations are reduced. Further, in order to obtain the film roll of the present invention, it is necessary to suppress the variation of the DC negative charge to be applied within an average negative charge (set value) of ± 20%, more preferably within ± 10%. .

(6) Optimization of stretching conditions As a method of biaxially stretching an unstretched film, the unstretched film is stretched in the longitudinal direction with a roll-type stretching machine and stretched in the transverse direction with a tenter-type stretching machine, followed by heat setting treatment and relaxation. It is necessary to employ a longitudinal / lateral stretching method for performing the treatment. Furthermore, in order to obtain the film roll of the present invention, it is necessary to adopt a so-called longitudinal-longitudinal-lateral stretching method as a biaxial stretching method. The longitudinal-longitudinal-lateral stretching method means that, in longitudinal stretching of a substantially unoriented polyamide film, the first-stage stretching is performed, and the second-stage stretching is continuously performed without cooling to Tg or less. Thereafter, it is a method of transverse stretching at a magnification of 3.0 times or more, preferably 3.5 times or more, and further heat setting. And in order to obtain the film roll of this invention, when performing longitudinal-longitudinal-lateral stretching mentioned above, it is necessary to make the longitudinal stretch ratio of the 1st stage higher than the longitudinal stretch ratio of the 2nd stage. That is, by making the first stage longitudinal draw ratio higher than the second stage longitudinal draw ratio, it is possible to obtain a film roll with good physical properties such as boiling water shrinkage and few variations in those physical properties. It becomes. In addition, when performing longitudinal-longitudinal-lateral stretching, it is usually easier to make the first-stage longitudinal stretching ratio lower than the second-stage longitudinal stretching ratio without causing sticking to the roll during the first-stage stretching. However, by using a special roll such as a Teflon (trademark registered) roll, even if the longitudinal stretch ratio of the first stage is higher than the longitudinal stretch ratio of the second stage, it causes sticking to the roll. It becomes possible to stretch easily.

  When performing longitudinal-longitudinal-lateral stretching as described above, the first-stage longitudinal stretching is preferably stretched about 2.0 to 2.4 times at a temperature of 80 to 90 ° C. When the draw ratio at the first stage is out of the above range and becomes high, the thickness unevenness in the vertical direction becomes large, which is not preferable. In addition, the longitudinal stretching in the second stage is preferably stretched about 1.3 to 1.7 times at a temperature of 65 to 75 ° C. If the draw ratio of the second stage falls outside the above range, it becomes unfavorable because the boil distortion increases and becomes unpractical.On the other hand, if the draw ratio of the second stage goes out of the above range, it becomes high. The strength in the direction (such as strength at 5% elongation) becomes low and becomes unpractical.

  Moreover, when performing longitudinal-longitudinal-lateral stretching as described above, hot roll stretching, infrared radiation stretching, or the like can be employed as the longitudinal stretching method. Further, when the polyamide-based resin film of the present invention is produced by such a longitudinal-longitudinal-lateral stretching method, not only the thickness unevenness in the vertical direction, the variation in physical properties and the variation are reduced, but also the variation in physical properties in the lateral direction And variations can also be reduced. In the case of longitudinal-longitudinal-lateral stretching, the total longitudinal stretching condition is preferably 3.0 to 4.5 times.

  Moreover, when performing longitudinal-longitudinal-lateral stretching, it is preferable to stretch the lateral stretching at a temperature of 120 to 140 ° C. by about 4.0 to 5.5 times. If the transverse stretching ratio falls outside the above range, the transverse strength (5% elongation strength, etc.) becomes low and impractical, which is not preferable. Conversely, the transverse stretching ratio falls within the above range. If the deviation is high, the thermal contraction rate in the lateral direction is increased, which is not preferable. On the other hand, if the transverse stretching temperature falls outside the above range, it becomes unpreferable because the boil distortion becomes large and becomes impractical, and conversely, if the transverse stretching temperature rises outside the above range, It is not preferable because the strength (strength at 5% elongation, etc.) decreases and becomes impractical.

  Furthermore, in order to obtain the film roll of this invention, it is preferable to perform the heat setting process after longitudinal-longitudinal-lateral stretching at the temperature of 180-230 degreeC. If the temperature of the heat setting treatment falls outside the above range, the heat shrinkage rate in the longitudinal direction and the transverse direction increases, which is not preferable. On the contrary, if the temperature of the heat setting treatment rises outside the above range, biaxial stretching Since the impact strength of a film becomes low, it is not preferable.

  In addition, in order to obtain the film roll of the present invention, it is preferable to relax the relaxation treatment after heat setting by 2 to 10%. If the rate of relaxation treatment falls outside the above range, the thermal contraction rate in the longitudinal direction and the transverse direction increases, which is not preferable. Conversely, if the rate of relaxation treatment falls outside the above range, the longitudinal direction and the width direction The strength (such as strength at 5% elongation) becomes low and becomes unpractical.

  Further, the width of the film roll is not particularly limited, but from the viewpoint of easy handling, the lower limit of the width of the film roll is preferably 0.35 m or more, and more preferably 0.50 m or more. . On the other hand, the upper limit of the width of the film roll is preferably 2.5 m or less, more preferably 2.0 m or less, and further preferably 1.5 m or less. In addition, the winding length of the film roll is not particularly limited, but the lower limit of the winding length of the film roll is preferably 500 m or more and more preferably 1,000 m or more from the viewpoint of ease of winding and handling. . On the other hand, the upper limit of the roll length of the film roll is preferably 2,5000 m or less, more preferably 20,000 m or less, and further preferably 15,000 m or less. In addition, when a film thickness is about 15 micrometers, it is especially preferable in it being 12000 m or less. In addition, as the winding core, usually, paper of 3 inches, 6 inches, 8 inches, etc., a plastic core or a metal core can be used.

  On the other hand, the thickness of the film constituting the polyamide film roll of the present invention is not particularly limited. For example, the packaging polyamide film is preferably 8 to 50 μm, more preferably 10 to 30 μm.

  In addition, the polyamide resin film constituting the film roll of the present invention includes a lubricant, an anti-blocking agent, a thermal stabilizer, an antioxidant, an antistatic agent, a light-proofing agent, and an impact resistance within a range that does not impair the properties. It is also possible to include various additives such as an improving agent. In particular, it is preferable to contain various inorganic particles for the purpose of improving the slipperiness of the biaxially stretched film. In addition, as the inorganic particles, those having an average particle size (that is, average particle size) of 0.5 to 5.0 μm are preferable, and silica particles are particularly preferable. If the average particle size is less than 0.5 μm, good slipperiness will not be obtained. Conversely, if the average particle size is more than 5.0 μm, transparency will be poor or so-called “missing” will occur during printing. This is not preferable. In addition, the measurement of the average particle diameter can employ a method of calculating the weight average diameter from the particle size distribution obtained by a Coulter counter, and can be measured from the particles before being added to the polyamide resin. It is also possible to measure from particles precipitated by dissolving a resin-based resin film with an acid. Moreover, it is preferable to add an organic lubricant such as ethylenebisstearic acid that exhibits the effect of reducing the surface energy because the slipping property of the film constituting the film roll becomes excellent.

  Furthermore, the polyamide-based resin film constituting the film roll of the present invention can be subjected to heat treatment or humidity control treatment in order to improve dimensional stability depending on the application. In addition, in order to improve the adhesion of the film surface, corona treatment, coating treatment, flame treatment, etc., and processing such as printing, vapor deposition and the like can be performed.

  It should be noted that only one of the above-mentioned means (1) to (6) does not effectively contribute to the reduction of the physical property variation of the film roll, and the means (1) to (6) are combined. Therefore, it is considered that the change in physical properties of the film roll can be reduced very efficiently.

  Hereinafter, a method for laminating an adhesion modified layer on the surface of the polyamide resin film constituting the polyamide resin film roll having extremely uniform physical properties as described above will be described. In the present invention, “dispersion” refers to an emulsion, dispersion, or suspension, and “grafting” refers to a graft portion comprising a polymer different from the main chain in the polymer main chain. The term “grafted polyester” refers to a polyester having a graft portion made of a polymer different from the polyester with respect to the polyester main chain, and the “aqueous solvent” is mainly composed of water. , Refers to a solvent containing an aqueous organic solvent as required.

(Copolymerized polyester aqueous dispersion)
The copolymerized polyester aqueous dispersion that can be used in the present invention contains particles of grafted polyester and water, an aqueous solvent or an organic solvent, and exhibits a translucent to milky white appearance. This grafted polyester has a polyester main chain and a graft portion formed by a radical polymerizable monomer including a radical polymerizable monomer having a hydrophilic group.

  The average particle diameter of the grafted polyester particles in the copolymerized polyester aqueous dispersion measured by a laser light scattering method is 500 nm or less, preferably 10 nm to 500 nm, more preferably 10 nm to 300 nm. When the average particle diameter exceeds 500 nm, the coating film strength after coating decreases.

  The content of the grafted polyester particles in the copolymerized polyester aqueous dispersion is usually 1% to 50% by weight, preferably 3% to 30% by weight.

When ¹³ C-NMR (measuring conditions: 125 MHz, 25 ° C., measuring solvent: heavy water, DSS signal is 5 Hz or less) of a copolyester aqueous dispersion that can be used in the present invention is measured, Fourier is not applied to the weighting function. In the spectrum obtained by conversion, the half-value width of the carbonyl carbon signal derived from the polyester main chain is preferably 300 Hz or more, and the half-value width of the carbonyl carbon signal derived from the graft portion is preferably 150 Hz or less.

In general, it is known that the chemical shift, the half width, and the relaxation time in ¹³ C-NMR can be changed to reflect the surrounding environment where the observed carbon atom is placed. For example, a carbonyl carbon signal of a polymer dissolved in heavy water is observed in the range of 170 to 200 ppm, and its half-value width is approximately 300 Hz or less. On the other hand, a carbonyl carbon signal of a polymer that is insoluble in heavy water is observed in the range of 170 to 200 ppm, and its half-value width is about 300 Hz or more.

  Since the polyester main chain and graft portion in the grafted polyester particles have the half width as described above, the particles in the copolymerized polyester aqueous dispersion that can be used in the present invention have the polyester main chain in the aqueous dispersion medium. A core-shell structure as a core can be taken.

  The core-shell structure referred to here is, as is known in the art, a core portion made of a polymer that is insoluble in a dispersion medium and in an aggregated state is made of a polymer that is soluble in a dispersion medium and in a dissolved state. A two-layer structure wrapped in a shell part. This structure is characteristic of a composite polymer dispersion formed by chemically bonding polymers having different solubility in a dispersion medium to each other. It is known that the structure cannot be expressed only by mixing. Furthermore, a mixture of polymers having different solubility in a simple dispersion medium cannot exist as a dispersion having a particle size of 500 nm or less.

  Since the particles in the aqueous copolymerized polyester dispersion used in the present invention have the core-shell structure as described above, the polymer particles can be obtained without using an emulsifier or an organic cosolvent often used in conventional dispersions. The dispersion state in the dispersion medium is stabilized. This is because the resin in the shell portion forms a sufficient hydration layer and protects the dispersed polymer particles.

  The coating film obtained from such a copolymerized polyester aqueous dispersion has very good adhesion to the polyamide film. Furthermore, since the blocking resistance is very excellent, it can be used without any problem even on a film substrate having a relatively low glass transition point. Moreover, when it is set as a laminated body, adhesiveness with the adhesive agent used when laminating printing ink or a sealant layer is also very favorable. Therefore, by using the polyamide-based resin laminated film of the present invention, the obtained laminate (laminate film) can be remarkably improved in durability in retort treatment and boiling water treatment. Further, when a soft grafted polyester having a glass transition temperature of the grafted polyester in the aqueous copolymerized polyester dispersion of 30 ° C. or lower, preferably 10 ° C. or lower is used, the durability of the laminate is further improved.

(Polyester main chain)
In the present invention, the polyester that can be used as the main chain of the grafted polyester is preferably a saturated or unsaturated polyester synthesized from at least a dicarboxylic acid component and a diol component, and the resulting polyester is a single polymer or 2 It can be a mixture of more than one polymer. A polyester that does not inherently disperse or dissolve in water is preferred. The weight average molecular weight of the polyester that can be used in the present invention is 5,000 to 100,000, preferably 5,000 to 50,000. When the weight average molecular weight is less than 5000, physical properties of the coating film such as post-processability of the dried coating film are deteriorated. Furthermore, when the weight average molecular weight is less than 5,000, the polyester itself serving as the main chain is easily water-soluble, so that the formed grafted polyester cannot form the core-shell structure described later. When the weight average molecular weight of the polyester exceeds 100,000, water dispersion becomes difficult. From the viewpoint of water dispersion, it is preferably 100,000 or less.

  The glass transition point is 30 ° C. or lower, preferably 10 ° C. or lower.

  The dicarboxylic acid component includes at least one aromatic dicarboxylic acid, at least one aliphatic and / or alicyclic dicarboxylic acid, and at least one dicarboxylic acid having a radically polymerizable unsaturated double bond. A dicarboxylic acid mixture is preferred. The aromatic dicarboxylic acid contained in the dicarboxylic acid mixture is 30 to 99.5 mol%, preferably 40 to 99.5 mol%, and the aliphatic and / or alicyclic dicarboxylic acid is 0 to 70 mol%. The dicarboxylic acid having a radically polymerizable unsaturated double bond is preferably 0.5 to 10 mol%, preferably 2 to 7 mol%, more preferably 3 to 6 mol%. When the content of the dicarboxylic acid containing a radically polymerizable unsaturated double bond is less than 0.5 mol%, it is difficult to effectively graft the radically polymerizable monomer to the polyester, The dispersed particle size tends to increase, and the dispersion stability tends to decrease.

  As the aromatic dicarboxylic acid, terephthalic acid, isophthalic acid, orthophthalic acid, naphthalenedicarboxylic acid, biphenyldicarboxylic acid and the like can be used. Furthermore, sodium 5-sulfoisophthalate may be used as necessary.

  As the aliphatic dicarboxylic acid, succinic acid, adipic acid, azelaic acid, sebacic acid, dodecanedioic acid, dimer acid, acid anhydrides thereof and the like can be used.

  As the alicyclic dicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,2-cyclohexanedicarboxylic acid, acid anhydrides thereof and the like can be used.

  Dicarboxylic acids containing radically polymerizable unsaturated double bonds include α, β-unsaturated dicarboxylic acids such as fumaric acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, and fats containing unsaturated double bonds. As the cyclic dicarboxylic acid, 2,5-norbornene dicarboxylic acid anhydride, tetrahydrophthalic anhydride, or the like can be used. Of these, fumaric acid, maleic acid and 2,5-norbornene dicarboxylic acid (endo-bicyclo- (2,2,1) -5-heptene-2,3-dicarboxylic acid) are preferred.

  The diol component is composed of at least one of an aliphatic glycol having 2 to 10 carbon atoms, an alicyclic glycol having 6 to 12 carbon atoms, and an ether bond-containing glycol.

  Examples of the aliphatic glycol having 2 to 10 carbon atoms include ethylene glycol, 1,2-propylene glycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, neopentyl glycol, 1,6 -Hexanediol, 3-methyl-1,5-pentanediol, 1,9-nonanediol, 2-ethyl-2-butylpropanediol and the like can be used.

  As the alicyclic glycol having 6 to 12 carbon atoms, 1,4-cyclohexanedimethanol or the like can be used.

  Examples of the ether bond-containing glycol include diethylene glycol, triethylene glycol, dipropylene glycol, and glycols obtained by adding 1 to several moles of ethylene oxide or propylene oxide to two phenolic hydroxyl groups of bisphenols, for example, 2,2 -Bis (4-hydroxyethoxyphenyl) propane or the like can be used. Polyethylene glycol, polypropylene glycol, and polytetramethylene glycol may be used as necessary.

  In addition to the dicarboxylic acid component and the diol component, a tri- or higher functional polycarboxylic acid and / or polyol can be copolymerized.

  The tri- or higher functional polycarboxylic acid includes (anhydrous) trimellitic acid, (anhydrous) pyromellitic acid, (anhydrous) benzophenone tetracarboxylic acid, trimesic acid, ethylene glycol bis (anhydrotrimellitate), glycerol tris (anne) Hydrotrimellitate) and the like can be used.

  As the trifunctional or higher functional polyol, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, or the like can be used.

  The tri- or higher functional polycarboxylic acid and / or polyol is 0 to 5 mol%, preferably 0 to 3 mol%, based on the total polycarboxylic acid component including the dicarboxylic acid component or the total polyol component including the diol component. Can be used in a range of

(Grafted part of grafted polyester)
The graft portion of the grafted polyester that can be used in the present invention is a monomer mixture containing at least one radical polymerizable monomer having a hydrophilic group or a group that can be changed to a hydrophilic group later. It can be a derived polymer.

  The polymer constituting the graft part has a weight average molecular weight of 500 to 50,000, preferably 4,000 to 50,000. When the weight average molecular weight is less than 500, the grafting rate decreases, so that hydrophilicity cannot be sufficiently imparted to the polyester, and it is generally difficult to control the weight average molecular weight of the graft portion to less than 500. is there. The graft portion forms a hydrated layer of dispersed particles. In order to provide a hydration layer having a sufficient thickness to the particles and obtain a stable dispersion, the weight average molecule of the graft portion derived from the radical polymerizable monomer is desirably 500 or more. The upper limit of the weight average molecular weight of the graft portion of the radical polymerizable monomer is preferably 50000 as described above in view of polymerizability in solution polymerization. The molecular weight within this range is controlled by appropriately selecting the polymerization initiator amount, monomer dropping time, polymerization time, reaction solvent, and monomer composition, and appropriately combining a chain transfer agent and a polymerization inhibitor as necessary. You can do it.

  The glass transition point is 30 ° C. or lower, preferably 10 ° C. or lower.

  As the hydrophilic group possessed by the radical polymerizable monomer, a carboxyl group, a hydroxyl group, a sulfonic acid group, an amide group, a quaternary ammonium salt, a phosphoric acid group, or the like can be used. As a group that can be changed to a hydrophilic group, an acid anhydride, glycidyl, chloro, or the like can be used. The dispersibility of the grafted polyester in water can be controlled by the hydrophilic group introduced into the polyester by grafting. Among the hydrophilic groups, the carboxyl group can accurately determine the amount of the grafted polyester introduced into the grafted polyester using an acid value known in the art, so the dispersibility of the grafted polyester in water is controlled. This is preferable.

  Examples of carboxyl group-containing radical polymerizable monomers include acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, citraconic acid, and the like, and maleic anhydride that easily generates carboxylic acid in contact with water / amine. Products, itaconic anhydride, methacrylic anhydride and the like can be used. Preferred carboxyl group-containing radical polymerizable monomers are acrylic acid anhydride, methacrylic acid anhydride and maleic acid anhydride.

  In addition to the above-mentioned hydrophilic group-containing radical polymerizable monomer, it is preferable to copolymerize a radical polymerizable monomer that does not contain at least one hydrophilic group. In the case of only the hydrophilic group-containing monomer, grafting to the polyester main chain does not occur smoothly, and it is difficult to obtain a good copolymerized polyester aqueous dispersion. Highly efficient grafting can be carried out only by copolymerizing a radically polymerizable monomer that does not contain at least one hydrophilic group.

  As the radically polymerizable monomer not containing a hydrophilic group, one or more combinations of monomers having an ethylenically unsaturated bond and not containing a hydrophilic group as described above are used. Examples of such monomers include acrylic acid esters such as methyl acrylate, ethyl acrylate, isopropyl acrylate, n-butyl acrylate, 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and hydroxypropyl acrylate; Methacrylic acid esters such as methyl methacrylate, ethyl methacrylate, isopropyl methacrylate, n-butyl methacrylate, isobutyl methacrylate, n-hexyl methacrylate, lauryl methacrylate, 2-hydroxyethyl methacrylate, hydroxylpropyl methacrylate; acrylamide Acrylic acid or methacrylic acid derivatives such as N-methylolacrylamide and diacetoneacrylamide; Nitriles such as acrylonitrile and methacrylonitrile; Vinyl acetate and vinyl propionate Vinyl esters such as vinyl benzoate; Vinyl ethers such as vinyl methyl ether, vinyl ethyl ether and vinyl isobutyl ether; Vinyl ketones such as vinyl methyl ketone, vinyl hexyl ketone and methyl isopropenyl ketone; N-vinyl pyrrole, N-vinyl N-vinyl compounds such as carbazole, N-vinylindole and N-vinylpyrrolidone; vinyl halides such as vinyl chloride, vinyldenide, vinyl bromide and vinyl fluoride; styrene, α-methylstyrene, t-butylstyrene, And aromatic vinyl compounds such as vinyl toluene and vinyl naphthalenes. These monomers can be used alone or in combination of two or more.

  The use ratio of the hydrophilic group-containing monomer and the monomer that does not contain a hydrophilic group is determined in consideration of the amount of the hydrophilic group to be introduced into the grafted polyester. (Containing monomer: monomer not containing a hydrophilic group) is 95: 5 to 5:95, preferably 90:10 to 10:90, more preferably 80:20 to 40:60.

  When a carboxyl group-containing monomer is used as the hydrophilic group-containing monomer, the total acid value of the grafted polyester is 600-4000 eq. / 106 g, preferably 700-3000 eq. / 106 g, most preferably 800-2500 eq. / 106 g. Acid value is 600 eq. In the case of / 106 g or less, when the grafted polyester is dispersed in water, it is difficult to obtain a copolyester aqueous dispersion having a small particle diameter, and the dispersion stability of the copolyester aqueous dispersion is lowered. Acid value is 4000 eq. In the case of / 106 g or more, the water resistance of the adhesion-modified layer formed from the copolyester aqueous dispersion is lowered.

  The weight ratio (polyester: radically polymerizable monomer) between the polyester main chain and the graft portion in the grafted polyester is 40:60 to 95: 5, preferably 55:45 to 93: 7, and more preferably 60:40. It is in the range of ~ 90: 10.

  When the weight ratio of the polyester main chain is 40% by weight or less, the above-described excellent performance of the base polyester, that is, high processability, excellent water resistance, and excellent adhesion to various substrates can be sufficiently exhibited. On the contrary, the undesirable performance of the acrylic resin, that is, low processability, gloss, water resistance and the like are added. When the weight ratio of the polyester is 95% by weight or more, the hydrophilic group amount of the graft portion imparting hydrophilicity to the grafted polyester is insufficient, and a good aqueous dispersion cannot be obtained.

(Solvent for grafting reaction)
The solvent for the grafting reaction is preferably composed of an aqueous organic solvent having a boiling point of 50 to 250 ° C. Here, the aqueous organic solvent means an organic solvent having a solubility in water at 20 ° C. of at least 10 g / L or more, preferably 20 g / L or more. An aqueous organic solvent having a boiling point exceeding 250 ° C. is unsuitable because it has a low evaporation rate and cannot be sufficiently removed even by high-temperature baking of the coating film after forming the coating film. Also, in the case of an aqueous organic solvent having a boiling point of 50 ° C. or lower, when the grafting reaction is carried out using it as a solvent, an initiator that decomposes into radicals at a temperature of 50 ° C. or lower must be used. Absent.

  As an aqueous organic solvent (first group) which dissolves polyester well and dissolves a hydrophilic group, particularly a carboxyl group-containing polymerizable monomer, and a polymer thereof relatively well, esters are used. Ketones such as methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; cyclic ethers such as tetrahydrofuran, dioxane, and 1,3-dioxolane; glycol ethers such as ethylene glycol dimethyl ether, propylene glycol methyl ether, Propylene glycol propyl ether, ethylene glycol ethyl ether, and ethylene glycol butyl ether; carbitols such as methyl carbitol, ethyl carbitol, and butyl carbitol; Recalls or lower esters of glycol ethers such as ethylene glycol diacetate and ethylene glycol ethyl ether acetate; ketone alcohols such as diacetone alcohol; N-substituted amides such as dimethylformamide, dimethylacetamide, and N-methylpyrrolidone; Etc.

  On the other hand, as an aqueous organic solvent (second group) that dissolves polyester relatively little but dissolves a hydrophilic monomer, particularly a polymerizable monomer containing a carboxyl group-containing polymerizable monomer, and a polymer thereof relatively well. , Water, lower alcohols, lower glycols, lower carboxylic acids, lower amines and the like. Preferred are alcohols having 1 to 4 carbon atoms and glycols.

  When the grafting reaction is carried out in a single solvent, one of the first group of aqueous organic solvents can be used. When carried out in a mixed solvent, a plurality of first group aqueous organic solvents or at least one first group aqueous organic solvent and at least one second group aqueous organic solvent can be used.

  The grafting reaction can be carried out either in a single solvent from the first group of aqueous organic solvents or in a mixed solvent comprising one kind of each of the first group and the second group of aqueous organic solvents. However, in view of the progress of the grafting reaction, the appearance and properties of the grafting reaction product and the aqueous dispersion derived from it, a mixture consisting of each of the first group and the second group of aqueous organic solvents. It is preferable to use a solvent. This is because gelation of the system is likely to occur due to cross-linking between polyester molecules in the grafting reaction of polyester, but gelation can be prevented by using a mixed solvent as described below.

  In the first group of solvents, the polyester molecular chains are in a state of extending a wide chain, while in the mixed solvent of the first group / second group, the polyester molecular chains are entangled in a narrow string shape. The state was confirmed by measuring the viscosity of the polyesters in these solutions. In the state in which the polyester molecular chain is extended, all the reaction points in the polyester main chain can contribute to the grafting reaction, so that the grafting rate of the polyester is increased, but at the same time, the rate at which intermolecular crosslinking occurs is also increased. On the other hand, when the polyester molecular chain is in the form of a thread, the reaction points inside the thread cannot contribute to the grafting reaction, and at the same time, the rate of cross-linking between molecules is reduced. Thus, the state of the polyester molecule can be adjusted by selecting the type of solvent, and thereby the grafting rate and intermolecular crosslinking by the grafting reaction can be controlled.

  A high grafting ratio and gelation suppression can be achieved in a mixed solvent system. The optimum mixing ratio of the mixed solvent of the first group / second group may vary depending on the solubility of the polyester used, etc., but the weight ratio of the mixed solvent of the first group / second group is usually 95: 5 to The range is 10:90, preferably 90:10 to 20:80, more preferably 85:15 to 30:70.

(Radical polymerization initiator and other additives)
As the radical polymerization initiator that can be used in the present invention, organic peroxides and organic azo compounds known to those skilled in the art can be used.

  Benzoyl peroxide, t-butyl peroxypivalate as organic peroxide, 2,2′-azobisisobutyronitrile, 2,2′-azobis (2,4-dimethylvaleronitrile), etc. as organic azo compounds Can be mentioned.

  The amount of radical polymerization initiator used for carrying out the grafting reaction is at least 0.2% by weight, preferably 0.5% by weight or more, based on the radical polymerizable monomer.

  In addition to the polymerization initiator, a chain transfer agent for adjusting the chain length of the graft portion, for example, octyl mercaptan, mercaptoethanol, 3-t-butyl-4-hydroxyanisole and the like may be used as necessary. In this case, it is desirable to add in the range of 0 to 5% by weight with respect to the radical polymerizable monomer.

(Grafting reaction)
The graft portion is formed by polymerization of the radical polymerizable unsaturated double bond and the radical polymerizable monomer in the polyester and / or the radical polymerizable unsaturated double bond and the radical polymerizable monomer. The reaction proceeds with the active end of the polymer. The reaction product after completion of the grafting reaction contains, in addition to the target grafted polyester, a polyester having no graft portion and a polymer of a radical polymerizable monomer not grafted with the polyester. When the ratio of the grafted polyester in the reaction product is low and the ratio of the polyester having no graft portion and the polymer of the radical polymerizable monomer not grafted is high, a dispersion having good stability is obtained. I can't get it.

  Usually, the grafting reaction can be performed by adding the radical polymerizable monomer and the radical initiator at a time to the solution containing the polyester under heating, or separately taking a certain time. After the dropwise addition, the reaction can be continued by further heating with stirring for a certain period of time. Alternatively, if necessary, a part of the radical polymerizable monomer is added first, and then the remaining radical polymerizable monomer and polymerization initiator are separately added dropwise over a certain period of time, and then further constant. The grafting reaction can be carried out by continuing heating with stirring for a period of time.

  The weight ratio between the polyester and the solvent is selected so that the reaction proceeds uniformly during the polymerization process in consideration of the reactivity between the polyester and the radical polymerizable monomer and the solvent solubility of the polyester. Usually, it is in the range of 70:30 to 10:90, preferably 50:50 to 15:85.

(Water dispersion of grafted polyester)
The grafted polyester that can be used in the present invention can be dispersed in water by charging it into an aqueous medium in a solid state or by dissolving it in a hydrophilic solvent and then adding it to an aqueous medium. In particular, when a monomer having an acidic group such as a sulfonic acid group and a carboxyl group is used as a radical polymerizable monomer having a hydrophilic group, the grafted polyester is neutralized with a basic compound. The grafted polyester can be easily dispersed in water as fine particles having an average particle diameter of 500 nm or less to prepare a copolymerized polyester aqueous dispersion.

  As the basic compound, a compound that volatilizes at the time of forming a coating film, or when a curing agent described below is blended, is baked and cured. As such a basic compound, ammonia, organic amines and the like are preferable. Examples of organic amines include triethylamine, N, N-diethylethanolamine, N, N-dimethylethanolamine, aminoethanolamine, N-methyl-N, N-diethanolamine, isopropylamine, iminobispropylamine, ethylamine, diethylamine, 3-Ethoxypropylamine, 3-diethylaminopropylamine, sec-butylamine, propylamine, methylaminopropylamine, dimethylaminopropylamine, methyliminobispropylamine, 3-methoxypropylamine, monoethanolamine, diethanolamine, triethanolamine Etc.

  The amount of the basic compound used is preferably such that the carboxyl group contained in the graft portion is at least partially neutralized or completely neutralized so that the pH value of the aqueous dispersion is in the range of 5.0 to 9.0. .

  As a method for preparing a copolyester aqueous dispersion neutralized with a basic compound, after completion of the grafting reaction, the solvent is removed from the reaction solution with an extruder or the like under reduced pressure to obtain a melt or solid (pellet) And then stirring the mixture under heating with heating or immediately after the grafting reaction is completed, adding the basic compound aqueous solution to the reaction solution and continuing the heating and stirring ( An aqueous dispersion can be prepared by a one-pot method). From the viewpoint of convenience, the one-pot method is preferable. In this case, if the boiling point of the solvent used for the grafting reaction is 100 ° C. or less, a part or all of it can be easily removed by distillation.

(Adhesion modified layer)
In the polyamide film laminate of the present invention, the adhesion modifying layer present on at least one side of the polyamide film substrate is formed by applying a coating agent containing the above copolymerized polyester aqueous dispersion on the polyamide film substrate. The

  The above-mentioned copolymerized polyester aqueous dispersion can be used as it is as a coating agent for forming an adhesion-modified layer, but it can be used as an adhesive-modified layer by adding a crosslinking agent (curing resin) and curing. Water resistance can be imparted.

  As a crosslinking agent, phenol formaldehyde resin of a condensate of alkylated phenols, cresols and the like with formaldehyde; adduct of urea, melamine, benzoguanamine, etc. with formaldehyde, this adduct and alcohol having 1 to 6 carbon atoms An amino resin such as an alkyl ether compound comprising: a polyfunctional epoxy compound; a polyfunctional isocyanate compound; a blocked isocyanate compound; a polyfunctional aziridine compound; an oxazoline compound, and the like.

  Examples of the phenol formaldehyde resin include alkylated (methyl, ethyl, propyl, isopropyl or butyl) phenol, p-tert-amylphenol, 4, 4′-sec-butylidenephenol, p-tert-butylphenol, o-, m-, p-cresol, p-cyclohexylphenol, 4,4'-isopropylidenephenol, p-nonylphenol, p-octylphenol, 3-pentadecylphenol, phenol, phenyl o-cresol, p-phenylphenol, xylenol, etc. Mention may be made of condensates of phenols and formaldehyde.

  Examples of amino resins include methoxylated methylol urea, methoxylated methylol N, N-ethyleneurea, methoxylated methylol dicyandiamide, methoxylated methylol melamine, methoxylated methylol benzoguanamine, butoxylated methylol melamine, butoxylated methylol benzoguanamine, and the like. However, preferably, methoxylated methylol melamine, butoxylated methylol melamine, methylolated benzoguanamine and the like can be mentioned.

  Examples of the polyfunctional epoxy compound include diglycidyl ether of bisphenol A and oligomer thereof, diglycidyl ether of hydrogenated bisphenol A and oligomer thereof, orthophthalic acid diglycidyl ester, isophthalic acid diglycidyl ester, terephthalic acid diglycidyl ester, p-oxybenzoic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, hexahydrophthalic acid diglycidyl ester, succinic acid diglycidyl ester, adipic acid diglycidyl ester, sebacic acid diglycidyl ester, ethylene glycol diglycidyl ether, propylene Glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, 1,6-hexanediol diglycidyl ether And polyalkylene glycol diglycidyl ethers, trimellitic acid triglycidyl ester, triglycidyl isocyanurate, 1,4-diglycidyloxybenzene, diglycidyl propylene urea, glycerol triglycidyl ether, trimethylolpropane triglycidyl ether, pentaerythritol tri Examples thereof include glycidyl ether and triglycidyl ether of glycerol alkylene oxide adduct.

  As the polyfunctional isocyanate compound, a low-molecular or high-molecular aromatic or aliphatic diisocyanate or a trivalent or higher polyisocyanate can be used. Examples of polyisocyanates include tetramethylene diisocyanate, hexamethylene diisocyanate, toluene diisocyanate, diphenylmethane diisocyanate, hydrogenated diphenylmethane diisocyanate, xylylene diisocyanate, hydrogenated xylylene diisocyanate, isophorone diisocyanate, and trimers of these isocyanate compounds. There is. Further, an excess amount of these isocyanate compounds and low molecular active hydrogen compounds such as ethylene glycol, propylene glycol, trimethylolpropane, glycerin, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, and triethanolamine, or polyester polyols, poly The terminal isocyanate group containing compound obtained by making it react with polymer active hydrogen compounds, such as ether polyols and polyamides, can be mentioned.

  The blocked isocyanate can be prepared by subjecting the above isocyanate compound and blocking agent to an addition reaction by a conventionally known appropriate method. Examples of the isocyanate blocking agent include phenols such as phenol, cresol, xylenol, resorcinol, nitrophenol and chlorophenol; thiophenols such as thiophenol and methylthiophenol; oximes such as acetoxime, methylethylketoxime and cyclohexanone oxime; Alcohols such as methanol, ethanol, propanol and butanol; halogen-substituted alcohols such as ethylene chlorohydrin and 1,3-dichloro-2-propanol; tertiary alcohols such as t-butanol and t-pentanol; -Lactams such as caprolactam, δ-valerolactam, ν-butyrolactam, β-propyllactam; aromatic amines; imides; acetylacetone, acetoacetate, malonic acid Active methylene compounds such as Chiruesuteru; mercaptans; imines; ureas; diaryl compounds; can be mentioned sodium bisulfite and the like.

  These crosslinking agents may be used alone or in combination of two or more.

  As a compounding quantity of a crosslinking agent, 5 to 40 weight% is preferable with respect to grafted polyester.

  As a method of blending the crosslinking agent, (1) when the crosslinking agent is water-soluble, directly dissolving or dispersing in the aqueous dispersion, or (2) when the crosslinking agent is oil-soluble, after completion of the grafting reaction Alternatively, a method of adding a cross-linking agent before or after water dispersion to coexist with polyester in the core part can be used. These methods can be appropriately selected depending on the type and properties of the crosslinking agent. Further, a curing agent or an accelerator can be used in combination with the crosslinking agent.

  Additives such as antistatic agents, inorganic lubricants, and organic lubricants can be mixed with the coating agent that can be used in the present invention as long as the effects of the present invention are not impaired.

  The adhesive modification layer that can be used in the present invention can further contain additives such as an antistatic agent, an inorganic lubricant, and an organic lubricant within a range that does not impair the effects of the present invention. And applied to the substrate surface.

  As a method for applying a coating agent containing a copolymerized polyester aqueous dispersion to a polyamide film substrate in order to form an adhesion modified layer, known coating methods such as gravure method, reverse method, die method, bar method, dip method, etc. A scheme may be used.

The coating amount of the coating agent, 0.01 to 1 g / ^{m 2} as solids, preferably coated so as to 0.02 to 0.5 g / ^{m 2.} When the coating amount is 0.01 g / m ² or less, sufficient adhesion strength between the adhesion modified layer and the other layer cannot be obtained. When it is 1 g / m ² or more, blocking occurs, which causes a practical problem.

  The adhesion-modified layer is applied to the biaxially stretched polyamide film base material, or applied to the unstretched or uniaxially stretched polyamide film base material, and then dried. It can be prepared by stretching or biaxial stretching followed by heat setting. The drying temperature after applying the coating agent is 150 ° C. or higher, preferably 200 ° C. or higher, and drying and heat setting makes the coating film stronger and improves the adhesion between the adhesion-modified layer and the polyamide film substrate. To do.

  When extending | stretching after application | coating, it is necessary to control the moisture content of an application | coating film in the range of 0.1 to 2%, in order for the drying after application | coating not to impair the stretchability of an application | coating film. After stretching, drying and heat-setting at 200 ° C. or higher greatly improves the adhesion between the re-adhesion modified layer having a strong coating film and the polyamide film substrate.

  The adhesion-modified layer that can be used in the laminate of the present invention is formed by applying a coating agent containing a copolymerized polyester aqueous dispersion, and the copolymerized polyester aqueous dispersion comprises grafted polyester particles, an aqueous solvent, The grafted polyester has a polyester main chain and a graft portion formed by a radical polymerizable monomer including a radical polymerizable monomer having a hydrophilic group.

  In addition, when laminating using the polyamide-based resin laminated film roll of the present invention obtained as described above, for example, the following ink layer, adhesive layer, and sealant layer can be provided.

(Ink layer)
In the polyamide-based film laminate of the present invention, an ink layer is laminated on an adhesion modified layer formed on a polyamide film substrate.

  As the printing ink for forming the ink layer, an ink using a cellulose derivative as a binder or a gravure ink using a synthetic resin as a binder can be mainly used. In particular, when water resistance is required, a curing agent can be added to an ink containing vinyl chloride, polyester, polyether, polyol or the like having a hydroxyl group at the end of the polymer chain as a binder. The ink layer is formed entirely or partially on the adhesion modified layer or as an arbitrary pattern.

(Adhesive layer)
In the polyamide film laminate of the present invention, an adhesive layer is laminated on the ink layer. The thickness of the adhesive layer is usually 0.1 μm to 10 μm.

  As the adhesive forming the adhesive layer, when the sealant layer laminated on the adhesive layer is laminated by extrusion lamination, an isocyanate-based adhesive is preferable. As the isocyanate-based adhesive, for example, a polyurethane or a polyurethane prepolymer which is a reaction product of diisocyanate and a polyhydric alcohol and has an isocyanate group at a molecular end can be used as a one-pack type. Alternatively, a two-component type in which a polyisocyanate and a polyurethane prepolymer having a polyol or a hydroxyl group at a molecular terminal are mixed immediately before use can be used.

  When the sealant layer to be laminated on the adhesive layer is laminated by dry lamination, vinyl-based, acrylic-based, polyamide-based, epoxy-based, and urethane-based adhesives known to those skilled in the art can be used as the adhesive. . Among these, a two-component polyurethane adhesive in which polyisocyanate and polyol are mixed immediately before use is preferable.

  The adhesive layer can be formed by applying the liquid adhesive on the ink layer using a method known to those skilled in the art.

(Sealant layer)
In the polyamide-based film laminate of the present invention, a sealant layer is laminated on the adhesive layer. The thickness of the sealant layer is usually 20 μm to 100 μm. The sealant layer can be formed by extruding or dry laminating a synthetic resin such as low density polyethylene (LDPE), ethylene-vinyl acetate copolymer (EVA), ionomer, polypropylene (PP).

  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. .

  Further, the properties of the raw material chips A to E used in the examples and comparative examples, the composition of the raw material chips used in the examples and comparative examples, and the film forming conditions of the film rolls in the examples and comparative examples are shown in Table 1, respectively. It is shown in 2. The chips A, C, and D are made of nylon 6 (relative viscosity = 2.8, Tg = 41 ° C.) 97.00% by weight and silica particles 3.00% by weight. Nylon 6 (relative viscosity = 2.8, Tg = 41 ° C) 96.45 wt%, polymetaxylylene adipamide (relative viscosity = 2.1) 3.00 wt%, ethylenebisstearic acid amide 0.15 wt% %, Silica particles 0.40% by weight. In addition, the silica particles added to the chips A and C have an average particle system of about 3.0 μm, and the silica particles added to the chip B have an average particle system of about 1.8 μm. The silica particles added to the chips D and E have an average particle size of about 2.0 μm. The shapes of the chips A to E are all elliptic cylinders, and the chip A and the chip D, the chip B and the chip E are the same in cross section major axis, cross section minor axis, and chip length, respectively.

  On the other hand, the measuring method of the characteristic of the substance which comprises the adhesion modification layer apply | coated to the film in an Example and a comparative example is shown below. In the following description, “part” simply means “part by weight”, and “%” simply means “% by weight”.

[Weight average molecular weight]
0.03 g of the polymer was dissolved in 10 ml of tetrahydrofuran and measured with a GPC-LALLS apparatus low angle light scattering photometer LS-8000 (manufactured by Tosoh Corporation, tetrahydrofuran solvent, reference: polystyrene).

[Grafting efficiency of polyester]
Using a unity 500 (manufactured by Varian), the product obtained by the grafting reaction was subjected to ¹ H-NMR (220 MHz, measurement solvent CDC1 _{3) of} protons derived from the double bond of the double bond-containing component in the polyester. / DMSO-d ₆ ) was measured, and the graft efficiency was calculated using the following formula 1 based on the intensity change of the signal.

Polyester grafting efficiency = (1- (Relative strength of signal derived from double bond of double bond-containing component in grafted polyester / Relative strength of signal derived from double bond of component containing double bond in raw material polyester) )) X 100 (%) ... 1

  The relative intensity was calculated by comparison with the signal intensity of internal internal as a reference signal.

[Measurement of weight average molecular weight of graft part]
The polyester was hydrolyzed by refluxing the grafted polyester in a KOH / water-methanol solution. The decomposition product was extracted with THF under acidic conditions, and the grafted portion was purified from the extract by reprecipitation with hexane. The molecular weight of the obtained polymer was measured using a GPC apparatus (manufactured by Shimadzu Corporation, tetrahydrofuran solvent, polystyrene conversion), and the weight average molecular weight of the graft portion was calculated.

[Particle size of aqueous dispersion]
The aqueous dispersion was prepared to a solid content concentration of 0.1 wt% using only ion-exchanged water, and the particle size was measured at 20 ° C. using a laser light scattering particle size distribution meter Coulter model N4 (manufactured by Coulter).

[B-type viscosity of aqueous dispersion]
The viscosity of the aqueous dispersion was measured at 25 ° C. using a rotational viscometer (manufactured by Tokyo Keiki Co., Ltd., EM type).

[Measurement of half width of ¹³ C-NMR signal]
The aqueous dispersion was diluted with heavy water to a solid content concentration of 20% by weight, and then DSS was added thereto to prepare a measurement sample. Using UNITY 500 (manufactured by Varian), measurement conditions were set so that the DSS signal was 5 Hz or less at 25 ° C., then ¹³ C-NMR (125 MHz) of the sample was measured, and no weighting function was applied. Fourier transform. The half-value widths of the carbonyl carbon signal of the obtained polyester main chain and the carbonyl carbon signal of the graft portion were measured.

[Glass transition point (Tg)]
The aqueous dispersion was applied to a glass plate and then dried at 170 ° C. to obtain a polyester solid. 10 mg of this polyester solid content was taken into a sample pan and scanned at a rate of 10 ° C./min with a differential scanning calorimeter to measure Tg.

[Example 1]
<Adjustment of coating solution (copolymerized polyester aqueous dispersion) for forming an adhesion modified layer>
In a stainless steel autoclave equipped with a stirrer, thermometer and partial reflux condenser, 466 parts of dimethyl terephthalate, 466 parts of dimethyl isophthalate, 401 parts of neopentyl glycol, 443 parts of ethylene glycol, and 0.52 of tetra-n-butyl titanate The ester exchange reaction was carried out at 160 to 220 ° C. for 4 hours. Next, 23 parts of fumaric acid was added and the temperature was raised from 200 ° C. to 220 ° C. over 1 hour to carry out an esterification reaction. Next, the temperature was raised to 255 ° C., the pressure of the reaction system was gradually reduced, and the reaction was carried out with stirring under a reduced pressure of 0.2 mmHg for 1 hour and 30 minutes to obtain a polyester. The obtained polyester was light yellow and transparent, had a glass transition temperature of 60 ° C. and a weight average molecular weight of 12,000. The composition obtained by NMR measurement and the like was as follows.

Dicarboxylic acid component terephthalic acid 48mol%
Isophthalic acid 48mol%
4 mol% fumaric acid
Diol component Neopentyl glycol 50 mol%
Ethylene glycol 50 mol%

  In a reactor equipped with a stirrer, a thermometer, a reflux device and a quantitative dropping device, 75 parts of the polyester resin, 56 parts of methyl ethyl ketone, and 19 parts of isopropyl alcohol were placed and heated and stirred at 65 ° C. to dissolve the resin. After the resin was completely dissolved, a solution of 17.5 parts of methacrylic acid and 7.5 parts of ethyl acrylate and 1.2 parts of azobisdimethylvaleronitrile dissolved in 25 parts of methyl ethyl ketone was added at 0.2 ml / min. Was added dropwise to the polyester solution, and stirring was further continued for 2 hours after the completion of the dropping. After sampling for analysis (5 g) from the reaction solution, 300 parts of water and 25 parts of triethylamine were added to the reaction solution and stirred for 1 hour to prepare a dispersion of grafted polyester. Thereafter, the temperature of the obtained dispersion was raised to 100 ° C., and methyl ethyl ketone, isopropyl alcohol, and excess triethylamine were distilled off to obtain a copolymerized polyester aqueous dispersion.

The obtained dispersion was white and had an average particle diameter of 300 nm and a B-type viscosity at 25 ° C. of 50 cps. After adding 1.25 g of heavy water to 5 g of this dispersion to make the solid content concentration 20% by weight, DSS was added and 125 MHz ¹³ C-NMR was measured. The half width of the carbonyl carbon signal (160-175 ppm) of the polyester main chain was ∞ (no signal was detected), and the half width of the carbonyl carbon signal (181-186 ppm) of the methacrylic acid in the graft portion was 110 Hz. . The solution sampled at the end of the grafting reaction is dried at 100 ° C. under vacuum for 8 hours, and the solid content is measured for acid value, polyester grafting efficiency (NMR measurement), and hydrolysis of the grafted portion. The molecular weight was measured. The acid value of the solid content is 2300 eq. / 106 g. ^{In 1} H-NMR measurement, no fumaric acid-derived signal (δ = 6.8-6.9 ppm, doublet) was detected, and it was confirmed that the graft efficiency of polyester was 100%. The molecular weight of the graft portion was 10,000 weight average molecular weight.

  Thereafter, the dispersion obtained as described above was diluted with water to a solid content concentration of 5% to obtain a coating liquid (copolymerized polyester aqueous dispersion) A for forming an adhesion modified layer.

<Manufacture of polyamide-based resin laminated film roll>
On the other hand, the above-mentioned chips A and B were separately dried using a 15 kl blender apparatus while heating to about 120 ° C. for about 8.0 hours. When a predetermined amount of each chip was collected from the blender and the moisture content was measured, the moisture content of chips A and B was 800 ppm. The moisture content was measured using a Karl Fischer moisture meter (MKC-210 manufactured by KYOTO Electronics) under the conditions of a sample weight of 1 g and a sample heating temperature of 230 ° C.

  Thereafter, the chips in each blender were continuously and separately supplied to the hopper directly above the extruder by a quantitative screw feeder. The supply amount of chip A was 5.0% by weight, and the supply amount of chip B was 95.0% by weight. The hopper had a capacity of 150 kg of raw material chips, and the discharge rate of the extruder was 450 kg per hour. The inclination angle of the hopper was adjusted to 70 °. In Example 1, the average major axis, the average minor axis, and the average chip length of the polyamide resin chip (Chip A) other than the polyamide resin chip with the largest usage amount are the polyamide resin chips with the largest usage amount. The average major axis, average minor axis, and average chip length of (Chip B) are each included within a range of ± 20%.

  Further, when the chips A and B were supplied into the hopper, they were supplied to the hopper within a short time after drying so that the temperature of the chip in each blender would not become too low. The temperatures of chips A and B immediately before being supplied to the hopper were both about 91 ° C. Then, the supplied chips A and B are mixed in a hopper, melt-extruded from a T die at 270 ° C. by a single screw extruder, wound around a rotating metal roll cooled to 17 ° C., and rapidly cooled, An unstretched film having a thickness of 257 μm was obtained. In addition, the take-up speed of the unstretched film (rotational speed of the metal roll) is about 60 m / min. Met.

  In addition, the air gap when the molten resin is wound around the metal roll is adjusted to 40 mm, and by applying a negative DC charge of 100 mA at 11 ± 1.1 kv from the needle electrode to the molten film, glow discharge is performed. The molten resin was electrostatically adhered to a metal roll. Further, when the molten resin is wound around the metal roll, the portion where the molten resin comes into contact with the metal roll is opposite to the direction in which the resin is wound using the vacuum box over the entire width of the molten resin. By attracting in the direction, adhesion of the molten resin to the metal roll was promoted. The suction air velocity of the vacuum box is 5.0 ± 0.5 m / sec. Over the entire width of the suction port (that is, the entire width of the molten resin). It adjusted so that it might become.

Thereafter, the unstretched film obtained was stretched about 2.1 times (first longitudinal stretching) at a stretching temperature of about 85 ° C. by a Teflon roll, and then about 1 at a stretching temperature of about 70 ° C. by a ceramic roll. .6 longitudinal stretching (second longitudinal stretching). Thereafter, the coating liquid (copolymerization polyester aqueous dispersion) A for forming the above-mentioned adhesion-modified layer is continuously applied to the surface of the film after longitudinal stretching by a gravure method, and on a roll adjusted to 150 ° C. The coating solution was dried. The coating amount of the coating solution was adjusted so that an adhesion modified layer of 0.2 g / m ² was formed.

  And after apply | coating the adhesion | attachment modification layer to the surface of the film after longitudinal stretching as mentioned above, the longitudinally stretched sheet | seat is continuously guide | induced to a tenter, transversely stretched 4.0 times at about 130 degreeC, about 210 times By heat-fixing at ℃ and performing 5.0% lateral relaxation treatment, cooling and cutting and removing both edges continuously forms a biaxially stretched film of about 15 μm over 2000 m. A mill roll was prepared. In addition, the fluctuation range of the film surface temperature when the film is continuously produced 2000 m is the average temperature ± 0.8 ° C. in the preheating step, the average temperature ± 0.6 ° C. in the stretching step, and the average temperature ± 0.5 ° C. in the heat treatment step It was in the range. Furthermore, the obtained mill roll was slit into a width of 400 mm and a length of 2000 m, wound up on a 3-inch paper tube, and two polyamide-based resin laminated film rolls (slit rolls) were obtained.

  Then, using the obtained two slit rolls (namely, those obtained from the same mill roll), the characteristics were evaluated by the following method. In the following BS (boiling water shrinkage), BSx (maximum boiling water shrinkage), BSd (boiling water shrinkage direction difference), and refractive index measurement, the first sample cut-out portion is within 2 m from the end of film winding. Installed, the second to twentieth sample cutout sections are provided approximately every 100 m from the first sample cutout section, and the 21st sample cutout section is provided within 2 m from the beginning of film winding. A sample film was cut out from each of the sample cutout portions. The evaluation results are shown in Tables 3-9. When showing the evaluation results, for the impact strength and the laminate strength, the measured average values of the sample samples and the fluctuation range of the values of the sample samples were shown. For S-curl, the number of sample samples at each evaluation level and the overall evaluation level of all sample samples are shown.

[Boiling water shrinkage]
A biaxially oriented polyamide-based resin film (sample film) cut out from each cut-out portion of one slit roll was cut into a square shape with a side of 21 cm and left for 2 hours or more in an atmosphere of 23 ° C. and 65% RH. Draw a circle with a diameter of 20 cm centered on the center of the sample, draw a straight line passing through the center of the circle in the direction of 0 to 165 ° clockwise at 15 ° intervals, with the vertical direction (film drawing direction) being 0 °. The diameter in the direction was measured and taken as the length before treatment. The cut sample was then heat-treated in boiling water for 30 minutes, then removed and wiped off the moisture adhering to the surface, air-dried, and left in an atmosphere of 23 ° C. and 65% RH for 2 hours or more, as described above. The length of the straight line drawn in each diametric direction is measured and set as the length after treatment, and BS (boiling water shrinkage rate), BSx (maximum boiling water shrinkage rate), BSax (average boiling water shrinkage rate), BSd (boiling water shrinkage direction difference) and BSad (average boiling water shrinkage direction difference) were calculated.

  Then, the maximum / minimum in the maximum boiling water shrinkage (BSx) of all the samples is obtained, and the difference between the larger one of the maximum / minimum average boiling water shrinkage (BSax) and the average boiling water shrinkage And the ratio (%) of the difference to the average boiling water shrinkage (BSax) was calculated to obtain the variation rate of the maximum boiling water shrinkage (BSx) with respect to the average boiling water shrinkage (BSax). In addition, the maximum / minimum difference in boiling water shrinkage direction difference (BSd) of all samples is obtained, and the difference between the maximum / minimum average boiling water shrinkage direction difference (BSad) and the average boiling water shrinkage rate. The difference in boiling water shrinkage direction difference (BSd) with respect to the average boiling water shrinkage direction difference (BSad) is calculated by calculating the ratio (%) of the difference to the average boiling water shrinkage direction difference (BSad). The rate was determined.

[Vertical thickness unevenness]
The slit roll was slit to a width of about 3 cm over the entire length in the longitudinal direction to prepare a slit roll for thickness spot measurement. Thereafter, an average thickness, a maximum thickness, and a minimum thickness over the entire length in the longitudinal direction were determined using a thickness spot measuring device (wide range high sensitivity electronic micrometer K-313A) manufactured by Anritsu Corporation. And by calculating the difference between the average thickness and the larger one of the maximum thickness and the minimum thickness among the maximum thickness and the minimum thickness, and calculating the ratio (%) of the difference to the average thickness by the following formula 7. The variation rate of thickness over the entire length in the longitudinal direction was calculated.
Variation rate of thickness = | maximum thickness or minimum thickness−average thickness | / average thickness 7

[Refractive index]
Using an “Abbe refractometer 4T type” manufactured by Atago Co., Ltd., each sample film cut out from each sample cut-out part was left in an atmosphere of 23 ° C. and 65% RH for 2 hours or more, and then the refractive index in the thickness direction ( Nz) was measured. In addition, the average average refractive index of all sample films is calculated to calculate the difference between the maximum or minimum Nz and the average refractive index in all samples, and the ratio of the difference to the average refractive index is calculated as the variation rate. did.

[Impact strength]
Each sample film cut out from each cut-out part was allowed to stand in an atmosphere of 23 ° C. and 65% RH for 2 hours or more, and then a “film impact tester TSS type” manufactured by Toyo Seiki Seisakusho was used. The breaking strength was measured with a hemispherical impactor to determine the impact strength. The average impact strength of all sample films was also calculated.

[Lamination workability]
Using a slit roll (obtained from the same mill roll) different from the slit roll whose boiling water shrinkage rate, longitudinal thickness unevenness, refractive index, and impact strength were measured, the biaxially oriented polyamide constituting the slit roll After applying urethane AC agent (“EL443” manufactured by Toyo Morton Co., Ltd.) to a resin-based resin film, a 15 μm-thick LDPE (low density polyethylene) film using a single test laminator device manufactured by Modern Machinery Is extruded at 315 ° C., and a 40 μm thick LLDPE (Linear Low Density Polyethylene) film is continuously laminated thereon, and a laminate film roll having a three-layer structure composed of polyamide resin / LDPE / LLDPE is provided. Obtained. Moreover, the workability at the time of manufacturing a laminate film roll was evaluated in the following three stages.
○: No wrinkle on the roll and condition adjustment is not required. Δ: Roll wrinkle is eliminated by condition adjustment. ×: No matter how the condition is adjusted, wrinkle is generated on the roll.

[Lamination strength (peel strength)]
In addition, the laminate film cut out from the laminate film roll was cut out into a width of 15 mm and a length of 200 mm as a test piece, and “Tensilon UMT-II-500 type” manufactured by Toyo Baldwin Co., Ltd. was used. The peel strength between the polyamide resin film layer and the LDPE layer was measured under the condition of 65% humidity. The tensile rate was 10 cm / min, the peel angle was 180 degrees, and water was added to the peeled portion for measurement. The laminate strength is measured by cutting out the first sample piece within 2 m from the end of winding of the laminate film roll, and cutting out the second to twentieth sample pieces every about 100 m from the cut out portion of the first sample piece. The 21st sample piece was cut out within 2 m from the beginning of winding of the film, and the measurement was performed on each of the first to 21st sample pieces. Moreover, the average of those measured values was also calculated.

[Measurement of peel strength in hot water]
The laminate film laminated as described above is immersed in hot water at 90 ° C. for 30 minutes and then left at room temperature for about 30 seconds, and then peeled between the polyamide resin film layer and the LDPE layer by the same method as described above. The strength was measured.

[S-curl phenomenon]
The laminate film wound up as a laminate film roll as described above is folded into two parallel to the winding length direction using a test sealer manufactured by Seibu Machinery Co. Then, 10 mm in the vertical direction was intermittently heat-sealed at intervals of 150 mm to obtain a semi-finished product having a width of 200 mm. This was cut in the winding length direction and both edges were cut so that the seal portion was 10 mm, and then cut at the boundary of the seal portion in the direction perpendicular to this to produce a three-side seal bag (seal width: 10 mm). . From these three-sided sealing bags, a three-sided sealing bag made from a portion within 2 m from the end of winding of the laminate film roll is selected as the first sample, and about 100, 200,..., 1800, 3900 sealed bags produced from 1900 m apart were selected as the second to 20th samples, respectively, and 3 produced from the portion within 2 m from the start of the lamination film roll. A side seal bag was selected as the 21st sample. And after heat-treating those 21 three-way seal bags for 30 minutes in boiling water, hold them in an atmosphere of 23 ° C. and 65% RH all day and night. A load of 1 kg was applied to the entire surface of the bag, and the bag was removed after being held for a whole day and night, and the degree of bag curl (S-curl) was evaluated as follows.
◎: No warping at all. ○: Slight warping is observed. X: Warping is clearly observed. XX: Warping is remarkable.

[Example 2]
An unstretched film obtained in the same manner as in Example 1 was longitudinally stretched about 2.2 times (first longitudinal stretching) at a stretching temperature of about 90 ° C. by a Teflon roll, and then stretched at a temperature of about 70 by a ceramic roll. Longitudinal stretching (second longitudinal stretching) was performed at about 1.5 times at a temperature. Further, as in Example 1, the coating liquid A was applied to the longitudinally stretched sheet and dried, and then continuously led to a stenter and stretched 4.0 times at about 130 ° C. to about 210 ° C. The film was heat-fixed and subjected to 5.0% lateral relaxation treatment and then cooled, and both edges were cut and removed to continuously form a biaxially stretched film of about 15 μm over 2000 m. The fluctuation range of the film surface temperature when the film was continuously produced was the same as in Example 1. The obtained film was slit and wound in the same manner as in Example 1 to obtain a polyamide-based resin laminated film roll of Example 2. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 3]
The unstretched film obtained in the same manner as in Example 1 was longitudinally stretched in two stages in the same manner as in Example 1. Thereafter, in the same manner as in Example 1, the coating liquid A was applied to the longitudinally stretched sheet and dried, then continuously led to a stenter, and stretched 3.6 times at about 130 ° C., about 215 The film was cooled at a temperature of 3.0 ° C. and then subjected to a transverse relaxation treatment of 3.0%, and then cooled, and both edges were cut and removed to continuously form a biaxially stretched film of about 15 μm over 2000 m. . The fluctuation range of the film surface temperature when the film was continuously produced was the same as in Example 1. The obtained film was slit and wound in the same manner as in Example 1 to obtain a polyamide-based resin laminated film roll of Example 3. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 4]
The polyamide-based resin of Example 4 is the same as Example 1 except that the mixing ratio of the raw material chip A and the raw material chip B is 15.0% by weight of chip A and 85.0% by weight of chip B. A laminated film roll was obtained. In Example 4 as well, the average major axis, the average minor axis, and the average chip length of the polyamide resin chip (Chip A) other than the polyamide resin chip with the largest usage amount are the polyamide resin chips with the largest usage amount. The average major axis, average minor axis, and average chip length of (Chip B) are each included within a range of ± 20%. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 5]
A polyamide-based resin laminated film roll of Example 5 was obtained in the same manner as in Example 1 except that the raw material chips D and E were used instead of the raw material chips A and B, respectively (that is, in Example 5) A polyamide-based film roll was manufactured using 5.0 wt% Chip D and 95.0 wt% Chip E). In Example 5 as well, the average major axis, the average minor axis, and the average chip length of the polyamide resin chip (chip D) other than the polyamide resin chip with the largest usage amount are the polyamide resin chips with the largest usage amount. The average major axis, average minor axis, and average chip length of (Chip E) are each included within a range of ± 20%. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 6]
A polyamide-based resin laminated film roll of Example 6 was obtained in the same manner as in Example 1 except that when the raw material chips in the blender were supplied to the hopper immediately above the extruder, the hopper inclination angle was changed to 65 °. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 7]
The suction air velocity of the vacuum box when the molten resin is wound around the metal roll is 3.0 ± 0.5 m / sec over the entire width of the suction port. Except having adjusted so that it might become, it carried out similarly to Example 1, and obtained the polyamide-type resin laminated film roll of Example 7. FIG. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 8]
<Adjustment of coating solution (copolymerized polyester aqueous dispersion) for forming an adhesion modified layer>
The same adjustment as in Example 1 was applied except that the polyester resin obtained in Example 1 was changed to 90 parts, 7.0 parts of methacrylic acid, 3.0 parts of ethyl acrylate, and 0.48 parts of azobisdimethylvaleronitrile. A polymerized polyester aqueous dispersion was obtained. Thereafter, the dispersion was diluted with water to a solid content concentration of 5% to obtain a coating solution (copolymerized polyester aqueous dispersion) B for forming an adhesion modified layer.

  And the polyamide-type resin laminated film roll of Example 8 was obtained like Example 1 except having changed the coating liquid apply | coated to the sheet | seat after a longitudinal stretch to said coating liquid B. FIG. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Example 9]
<Adjustment of coating solution (copolymerized polyester aqueous dispersion) for forming an adhesion modified layer>
A polyester was obtained in the same manner as in Example 1, except that 457 parts of dimethyl terephthalate, 452 parts of dimethyl isophthalate, and 7.4 parts of dimethyl-5-sodium sulfoisophthalate were used. The obtained polyester was light yellow and transparent, had a glass transition temperature of 62 ° C. and a weight average molecular weight of 12,000. The composition obtained by NMR measurement and the like was as follows.

Dicarboxylic acid component terephthalic acid 49 mol%
Isophthalic acid 48.5 mol%
5-sodium sulfoisophthalic acid 2.5 mol%
Diol component Neopentyl glycol 50 mol%
Ethylene glycol 50 mol%

  A polyester polyester aqueous dispersion containing 100 parts of this polyester resin and not added with components such as methacrylic acid, ethyl acrylate and azobisdimethylvaleronitrile was obtained in the same manner as in Example 1, and then the dispersion was obtained. Was diluted with water to a solid content concentration of 5% to obtain a coating solution (copolymerized polyester aqueous dispersion) C for forming an adhesion modified layer.

  And the polyamide-type resin laminated | multilayer film roll of Example 9 was obtained like Example 1 except having changed the coating liquid apply | coated to the sheet | seat after a longitudinal stretch to said coating liquid C. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Comparative Example 1]
An unstretched film obtained in the same manner as in Example 1 was longitudinally stretched about 1.5 times (first longitudinal stretching) at a stretching temperature of about 90 ° C. by a Teflon roll, and then stretched at a temperature of about 70 by a ceramic roll. Longitudinal stretching (second longitudinal stretching) was performed at about 2.2 times at a temperature. Further, as in Example 1, the coating liquid A was applied to the longitudinally stretched sheet and dried, and then continuously led to a stenter, laterally stretched in the same manner as in Example 1, and heat-fixed to be laterally relaxed. After the treatment, the film was cooled and both edges were cut and removed to continuously form a biaxially stretched film of about 15 μm over 2000 m. The fluctuation range of the film surface temperature when the film was continuously produced was the same as in Example 1. Thereafter, the obtained film was slit and wound in the same manner as in Example 1 to obtain a polyamide-based resin laminated film roll of Comparative Example 1. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Comparative Example 2]
A polyamide-based resin laminated film roll of Comparative Example 2 was obtained in the same manner as in Example 1 except that the raw material chip C was used instead of the raw material chip A. In Comparative Example 2, the average major axis and the average chip length of the polyamide resin chip (chip C) other than the polyamide resin chip with the largest use amount are the polyamide resin chips (chip B) with the largest use amount. The average major axis and the average chip length are not included within the range of ± 20%. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Comparative Example 3]
Polyamide-based resin laminated film of Comparative Example 3 in the same manner as in Example 1 except that the predrying conditions of the raw material chips A and B were changed to a method of heating to about 100 ° C. over about 4.0 hours. Got a roll. After pre-drying, a predetermined amount of each chip was collected from the blender and the moisture content was measured. As a result, the moisture content of chips A and B was 1500 ppm, and the chips A and B just before being supplied to the hopper The temperatures were all about 85 ° C. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Comparative Example 4]
The polyamide of Comparative Example 4 was prepared in the same manner as in Example 1 except that the raw material chips A and B were pre-dried and then allowed to stand for about 5 hours in each blender before being supplied to the hopper immediately above the extruder. A system resin laminated film roll was obtained. The moisture content of chips A and B immediately before being supplied to the hopper was 800 ppm, and the temperature of chips A and B immediately before being supplied to the hopper was about 30 ° C. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Comparative Example 5]
A polyamide-based resin laminated film roll of Comparative Example 5 was obtained in the same manner as in Example 1 except that suction by a vacuum box was not performed when the molten resin was wound around a metal roll. And the characteristic of the obtained film roll was evaluated by the method similar to Example 1. FIG. The evaluation results are shown in Tables 3-9.

[Effects of Example Film]
From Tables 3 to 9, all of the film rolls of Examples 1 to 7 have very small longitudinal thickness unevenness over the entire roll, boiling water shrinkage rate, refractive index, laminate strength (peel strength) and hot water peel. It can be seen that fluctuations in physical properties such as strength are small. Moreover, it turns out that the film roll of Examples 1-7 with such a small fluctuation | variation of physical properties, such as boiling water shrinkage | contraction rate and a refractive index, does not generate an S-shaped curl phenomenon, but has favorable laminating property. In addition, it can be seen that the films constituting the film rolls of Examples 1 to 7 have good impact strength (toughness and pinhole resistance), and extremely high laminate strength (peel strength) and hot water peel strength. . On the other hand, the film rolls of Comparative Examples 1 to 5 have variations in physical properties such as vertical thickness unevenness, boiling water shrinkage rate, refractive index, laminate strength (peel strength) and hot water peel strength throughout the roll. It can be seen that the S-curl phenomenon is observed and the laminate processability is poor.

Since the polyamide-based resin laminated film roll of the present invention has excellent processing characteristics as described above, it can be suitably used for food retort processing.

Claims (21)

A polyamide-based resin laminated film formed by winding a polyamide-based resin film having a width of 0.2 m or more and 3.0 m or less and a length of 300 m or more and 30000 m or less, in which an adhesion-modified layer made of a copolyester is laminated on at least one surface. A roll,
A first sample cutout is provided within 2 m from the end of film winding, a final cutout is provided within 2 m from the start of film winding, and a sample cutout is provided approximately every 100 m from the first sample cutout. A polyamide-based resin laminated film roll characterized by satisfying the following requirements (1) to (3).
(1) For each sample cut out from each cutout part, when measuring the maximum boiling water shrinkage, which is the maximum value of the boiling water shrinkage in all directions, the average is the average value of the maximum boiling water shrinkage The boiling water shrinkage is 2% to 6%, and the variation rate of the maximum boiling water shrinkage of all the samples is within a range of ± 2% to ± 10% with respect to the average boiling water shrinkage (2) For each sample cut out from each cut-out part, the boiling water shrinkage direction difference, which is the absolute value of the difference between the boiling water shrinkage rate in the +45 degree direction with respect to the longitudinal direction and the boiling water shrinkage ratio in the −45 degree direction with respect to the longitudinal direction, is obtained. The average boiling water shrinkage direction difference, which is the average value of the boiling water shrinkage direction differences, is 1.5% or less, and the variation rate of the boiling water shrinkage direction difference of all the samples is the average boiling water shrinkage. Within ± 2% to ± 10% of rate direction difference There (3) rate of change in thickness over the entire length in the longitudinal direction in the coiled roll, it is within a range of ± 2% ~ ± 10% relative to the average thickness   When the refractive index in the thickness direction was measured for each sample cut out from each cutout portion, the average refractive index, which is the average value of those refractive indexes, was 1.500 or more and 1.520 or less, and all samples The polyamide-based resin laminated film roll according to claim 1, wherein a variation rate of the refractive index is in a range of ± 2% or less with respect to the average refractive index. The adhesion-modified layer is formed by applying a coating agent containing a copolymerized polyester aqueous dispersion, and the copolymerized polyester aqueous dispersion contains grafted polyester particles and an aqueous solvent, and the graft The grafted polyester has a polyester main chain and a graft portion formed by a radical polymerizable monomer including a radical polymerizable monomer having a hydrophilic group, and the average particle diameter of the grafted polyester particles is 500 nm. 2. The polyamide-based resin laminated film roll according to claim 1, wherein a half-value width of ¹³ C-NMR signal of carbonyl carbon derived from a polyester main chain of the grafted polyester particles is 300 Hz or more. .   The polyamide-based resin laminated film roll according to claim 1, wherein the main component of the polyamide constituting the polyamide-based resin film is nylon 6. A polyamide resin film roll wound up with a polyamide resin film before laminating the coating layer is
The polyamide resin laminated film roll according to claim 1, wherein the polyamide resin film is formed by winding a polyamide resin film formed from a mixture of two or more different polyamide resins.   The polyamide-based resin laminated film roll according to claim 1, wherein the wound polyamide-based resin film is laminated with a polyolefin-based resin film. A polyamide resin film roll wound up with a polyamide resin film before laminating the coating layer is
Extruding the melted polyamide resin from a T-die, bringing it into contact with a metal roll and cooling it, and winding a polyamide resin film obtained by biaxially stretching an unoriented sheet-like material The polyamide-based resin laminated film roll according to claim 1.   The polyamide-based resin laminated film roll according to claim 1, wherein the polyamide-based resin film is rolled up by a tenter stretching method.   The polyamide-based resin laminated film roll according to claim 1, wherein the polyamide-based resin film wound up sequentially biaxially is wound.   The polyamide-based resin laminated film roll according to claim 1, wherein the polyamide-based resin film is wound around a polyamide-based resin film stretched biaxially in a longitudinal direction and a transverse direction.   A sheet-like material composed of a substantially unoriented polyamide resin was stretched in the longitudinal direction in at least two stages so that the glass transition temperature of the polyamide resin + 20 ° C. and a magnification of 3 times or more. 2. The polyamide-based resin laminated film roll according to claim 1, wherein the polyamide-based resin film is a roll of a polyamide-based resin film that has been stretched in the transverse direction so as to have a magnification of 3 times or more.   The polyamide-based resin laminated film roll according to claim 1, wherein the polyamide-based resin film is heat-fixed after being subjected to a final stretching treatment.   The polyamide-based resin laminated film roll according to claim 1, wherein the polyamide-based resin film that has been subjected to a relaxation treatment after heat setting is wound up.   That at least one of a lubricant, an antiblocking agent, a heat stabilizer, an antioxidant, an antistatic agent, a light resistance agent, and an impact resistance improver is added to the wound polyamide resin film. The polyamide-based resin laminated film roll according to claim 1.   The polyamide resin laminated film roll according to claim 1, wherein inorganic particles are added to the wound polyamide resin film.   The polyamide resin laminated film roll according to claim 1, wherein the inorganic particles are silica particles having an average particle diameter of 0.5 to 5.0 μm.   The polyamide-based resin laminated film roll according to claim 1, wherein a higher fatty acid is added to the wound polyamide-based resin film. A manufacturing method for manufacturing the polyamide-based resin laminated film roll according to claim 1,
A film forming process for forming a film while melting and extruding a polyamide resin chip;
A biaxial stretching step of biaxially stretching the unstretched film obtained in the film forming step in the machine direction and the transverse direction;
A lamination step of laminating an adhesion modified layer layer on at least one side of the film after biaxial stretching,
The manufacturing method of the polyamide-type resin laminated | multilayer film roll characterized by satisfy | filling the following requirements (a)-(e).
(A) The biaxial stretching step involves stretching in the transverse direction after stretching in two stages in the longitudinal direction, and the first-stage stretching ratio in the two-stage stretching in the longitudinal direction is determined from the second-stage stretching ratio. (B) The film forming step mixes a chip made of a polyamide resin having the largest amount of use with one or more other polyamide resin chips having a composition different from that of the polyamide resin chip. After that, the polyamide resin chip to be used is melt-extruded, and the shape of each polyamide resin chip used is an elliptical cylinder having an elliptical cross section having a major axis and a minor axis, and the polyamide resin chip having the largest amount of use Other than polyamide resin chips, the average major axis, average minor axis, and average chip length of the polyamide resin chips with the largest use amount are ± 2 respectively. (C) an extruder provided with a funnel-shaped hopper as a raw material chip supply unit, being adjusted to have an average major axis, an average minor axis and an average chip length included in the range of And a step of melt extrusion using the hopper, the inclination angle of the hopper is adjusted to 65 degrees or more, and the moisture content of the polyamide resin chip before being supplied to the hopper is adjusted to 800 ppm or more and 1000 ppm or less. The temperature of the polyamide resin chip before being supplied to the hopper is adjusted to 80 ° C. or higher. (D) The film forming step uses the molten resin extruded from the extruder as a cooling roll. In addition to the step of cooling by winding, in the cooling step, the part that contacts the surface of the molten resin and the cooling roll, (E) The lamination step is performed to reduce the coating amount of the final adhesion-modified layer to 0.01 to 1.00 g / m by sucking in the direction opposite to the winding direction by the suction device over the entire width of the molten resin. ² to apply a coating solution for forming an adhesion-modified layer A preheating step that is performed before the longitudinal stretching step, and a heat treatment step that is performed after the longitudinal stretching step,
The fluctuation range of the surface temperature of the film at an arbitrary point in the longitudinal stretching step, the preheating step, and the heat treatment step is adjusted within a range of an average temperature ± 1 ° C. over the entire length of the film. The manufacturing method of the polyamide-type resin laminated film roll of Claim 18. A polyamide-based resin laminated film formed by winding a polyamide-based resin film having a width of 0.2 m or more and 3.0 m or less and a length of 300 m or more and 30000 m or less, in which an adhesion-modified layer made of a copolyester is laminated on at least one surface. A roll,
A first sample cutout is provided within 2 m from the end of film winding, a final cutout is provided within 2 m from the start of film winding, and a sample cutout is provided approximately every 100 m from the first sample cutout. When satisfying the following requirement (4), a polyamide-based resin laminated film roll.
(4) For each sample cut out from each cutout portion, when the peel strength when a polyolefin film is laminated is determined, the average peel strength, which is the average value of those peel strengths, is 500 g / 15 mm width or more. The variation rate of the peel strength of all the samples is within a range of ± 5% to ± 30% with respect to the average peel strength. A polyamide-based resin laminated film formed by winding a polyamide-based resin film having a width of 0.2 m or more and 3.0 m or less and a length of 300 m or more and 30000 m or less, in which an adhesion-modified layer made of a copolyester is laminated on at least one surface. A roll,
A first sample cutout is provided within 2 m from the end of film winding, a final cutout is provided within 2 m from the start of film winding, and a sample cutout is provided approximately every 100 m from the first sample cutout. When satisfying the following requirement (5), a polyamide-based resin laminated film roll.
(5) For each sample cut out from each cut-out part, when the hot water peel strength after 30 minutes immersion in 90 ° C. hot water when a polyolefin film is laminated is obtained, the hot water peel strength The average hot water peel strength of 150 g / 15 mm width or more, and the variation rate of the hot water peel strength of all the samples is ± 5% to ± 30% with respect to the average hot water peel strength. Is in range