JP2014046473A - Biaxially-oriented nylon film, laminate film, laminate packaging material, and method for producing biaxially-oriented nylon film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a biaxially-oriented nylon film having excellent deep drawing moldability at the time of cold molding.SOLUTION: In a biaxially-oriented nylon film, a value of b/a(%) is 46% or less when dynamic modulus E' of elasticity at -150°C is a, and dynamic modulus E' of elasticity at 23°C is b.

Description

  In particular, the present invention relates to a biaxially stretched nylon film, a laminate film, a laminate packaging material, and a method for producing a biaxially stretched nylon film that can be suitably used as a packaging material for cold forming.

Biaxially stretched nylon film (hereinafter also referred to as ONy film) is excellent in strength, impact resistance, pinhole resistance, etc., and is therefore often used for applications that require heavy strength loads such as heavy weight packaging and water packaging. (For example, patent document 1).
On the other hand, in recent years, the use of drawing a laminate packaging material including this ONy film is increasing. In addition, cold drawing that is superior in safety and freedom of shape (drawing formability) and can be made thinner and lighter than hot forming is being actively studied (for example, patents). Reference 2).
Laminate packaging materials including such ONy films are used for battery packaging, pharmaceuticals (especially PTP: Press through pack packaging, etc.), daily necessities (especially refill packaging for liquid detergents, etc.), foods, etc. Can be suitably used.

JP 2002-88174 A JP 2008-44209 A

  On the other hand, the packaging material for cold molding is required to further improve the drawability (deep drawability) as the capacity of batteries and the like increases. In addition, redrawable packaging materials for liquid detergents are required to have deep drawability when a straw or the like for an inlet is attached. Furthermore, with the aging of the population in recent years, with the development of medicines that are easily soluble in water to provide an excellent swallowing function (swallowing function), high moisture resistance and deep drawability are required even for PTP packaging materials. ing. However, in the laminate packaging material including the biaxially stretched nylon film as described in Patent Document 1 and Patent Document 2, there is no problem in normal drawing molding, but if deep drawing molding is performed, pinholes may be generated. There is.

  Therefore, an object of the present invention is to provide a biaxially stretched nylon film, a laminate film, a laminate packaging material, and a method for producing a biaxially stretched nylon film that have excellent deep drawability during cold forming.

  In the present invention, cold molding refers to molding performed at room temperature without heating among drawing molding. One means of such cold forming is to use a cold forming machine used for forming aluminum foil or the like to push the sheet material into the female mold with a male mold and press it at high speed. According to such cold forming, plastic deformation such as molding, bending, shearing and drawing can be generated without heating.

In order to solve the above-mentioned problems, the present invention provides the following biaxially stretched nylon film, laminate film, laminate packaging material, and method for producing a biaxially stretched nylon film.
That is, the biaxially stretched nylon film of the present invention has a value of b / a (%) when the dynamic elastic modulus E ′ at −150 ° C. is a and the dynamic elastic modulus E ′ at 23 ° C. is b. It is characterized by being 46% or less.

The laminate film of the present invention is characterized in that the biaxially stretched nylon film is laminated.
The laminate packaging material of the present invention is characterized by using the laminate film.

  The method for producing a biaxially stretched nylon film of the present invention is a method for producing a biaxially stretched nylon film for producing the biaxially stretched nylon film, and a raw film production process for forming a raw film from the raw material, A biaxial stretching step of biaxially stretching the original film, and a heat fixing step of heat-treating the film after the biaxial stretching step by heat treatment.

  ADVANTAGE OF THE INVENTION According to this invention, the manufacturing method of the biaxially stretched nylon film which has the deep drawing moldability excellent at the time of cold forming, a laminate film, a laminate packaging material, and a biaxially stretched nylon film can be provided.

It is a schematic block diagram which shows an example of the apparatus which manufactures the biaxially stretched nylon film of this invention.

Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.
[Configuration of biaxially stretched nylon film]
The biaxially stretched nylon film (ONy film) of this embodiment is formed by biaxially stretching a raw film made of nylon resin as a raw material and heat-fixing it at a predetermined temperature.
Nylon 6, nylon 8, nylon 11, nylon 12, nylon 6,6, nylon 6,10, nylon 6,12, etc. can be used as the nylon resin as the raw material. Nylon 6 (hereinafter also referred to as Ny6) is preferably used from the viewpoint of physical properties, melting characteristics, and ease of handling.
Here, the chemical formula of Ny6 is shown in the following formula (1).

  The number average molecular weight of the raw material nylon resin is preferably 15000 or more and 30000 or less, and more preferably 22000 or more and 24000 or less.

  In this embodiment, when the dynamic elastic modulus E ′ at −150 ° C. is a and the dynamic elastic modulus E ′ at 23 ° C. is b, the value of b / a (%) is 46% or less (more preferably 40% or less). When the value of b / a (%) exceeds the above upper limit, the deep drawability of the resulting film becomes insufficient.

Here, the dynamic elastic modulus (E ′), the dynamic loss rate (E ″), and the loss tangent (tan δ) in the dynamic viscoelasticity are represented by a non-resonant / forced vibration type device (Rheobibron DDV-II-EA / ORIENTEC) Can be obtained by measuring the dynamic viscoelastic temperature dispersion characteristics at a frequency of 110 Hz.
Specifically, a strip-shaped test piece having a length of 100 mm and a width of 2 mm is prepared, and the end of the test piece is attached to a lubricant paper so that the length of the test piece is 40 mm, and the temperature is 23. Leave for 48 hours or more in a test room at ℃ and humidity 50% RH. Then, using a non-resonant / forced vibration type device (Rheobibron DDV-II-EA / ORIENTEC) at a frequency of 110 Hz, the dynamic viscoelastic temperature dispersion characteristics (complex elastic modulus (E)) of the specimen after standing , Phase delay (δ)) is measured.

In addition, when one end of the polymer material is fixed and a stress (σ = σ ₀ sinwt) changing sinusoidally is applied to the other end, a strain (γ = γ ₀ sin (wt−δ) with a certain phase delay is applied. )) Occurs. The stress (σ *) and strain (γ *) having a time delay in this way are expressed as complex elastic modulus (E *) and have a relationship as shown in the following mathematical formula.
σ * = σ ₀ e ^iwt
γ * = γ ₀ e ^{i (wt−δ)}
E * = σ * / γ *
(In the above formula, σ ₀ and γ ₀ indicate the respective amplitudes, and w indicates the frequency.)
The complex elastic modulus (E *) is expressed separately as a real part (E ′) and an imaginary part (E ″) as shown in the following formula. It is said to be equivalent to the normal Young's modulus except when the damping is large, and the imaginary part (E ″) is said to be the dynamic loss rate and the dynamic loss elastic modulus. Represents the contribution of the viscous element. Furthermore, the imaginary part (E ″) is proportional to the amount of energy per cycle that is dissipated as heat when the specimen is deformed, and in an ideal viscous liquid, all of the energy consumed for deformation is converted into heat. Dissipated.
E * = E '+ iE "
The dynamic elastic modulus (E ′) and the dynamic loss rate (E ″) and the loss tangent (tan δ) are represented by the following formula (F1). The loss tangent (tan δ) is It is proportional to the ratio between the dissipated energy per cycle and the accumulated maximum potential energy.
tan δ = E ″ / E ′ (F1)
Then, if the dynamic viscoelastic temperature dispersion characteristics (complex elastic modulus (E), phase delay (δ)) are measured as described above, the dynamic elastic modulus (E ′), dynamic The loss rate (E ″) and loss tangent (tan δ) can be calculated.

  As described above, b which is the dynamic elastic modulus E ′ at 23 ° C. can be obtained by the method for measuring the dynamic viscoelastic temperature dispersion characteristic. On the other hand, a, which is the dynamic elastic modulus E ′ at −150 ° C., is the same as the method for measuring the dynamic viscoelastic temperature dispersion characteristic except that the conditions of the test chamber are set to temperature −150 ° C. and humidity 50% RH. Can be obtained.

In this embodiment, among the loss tangent tan δ in dynamic viscoelasticity represented by the following formula (F1), the peak value of tan δ in γ dispersion is 0.037 or more, and the peak value of tan δ in β dispersion is 0. It is preferably 045 or more. If either tan δ in γ dispersion or tan δ in β dispersion is less than the lower limit, the deep drawability of the resulting film tends to be lowered.
tan δ = E ″ / E ′ (F1)

Tan δ in β dispersion and γ dispersion can be obtained as follows. That is, by measuring the loss tangent (tan δ) while changing the temperature, a temperature-loss tangent curve can be created. The peak value of loss tangent (tan δ) in this temperature-loss tangent curve is said to be α dispersion, β dispersion, and γ dispersion from the high temperature side. Attributed to the rotational movement and side chain movement of the polymer.
From the above temperature-loss tangent curve, the peak value (peak height) and peak temperature (temperature at which the peak is reached) of tan δ in α dispersion, β dispersion, and γ dispersion can be read.

In addition, as a means for setting the characteristics of the ONy film (the peak value of tan δ in γ dispersion, the peak value of tan δ in β dispersion, and the value of b / a (%)) as described above, stretching during the production of the ONy film Examples include adjusting the magnification, stretching temperature, and heat setting temperature after stretching.
For example, as the heat setting temperature after stretching is lowered, the peak value of tan δ in γ dispersion and the peak value of tan δ in β dispersion tend to increase, and the value of b / a (%) tends to decrease. is there.

[Composition of laminate film]
The laminate film of this embodiment is configured by laminating one or two or more other laminate base materials on at least one surface of the above-described ONy film. Specifically, other laminate base materials include, for example, an aluminum layer, a film containing an aluminum layer, a polypropylene-based or polyethylene-based seal layer (sealant layer), and the like.
In addition, the laminate packaging material of the present embodiment is a polyester resin such as polyethylene terephthalate (PET), polyvinylidene chloride resin, polyvinylidene chloride copolymer resin, lubricant, or the like on at least one surface of the above-mentioned ONy film. A laminate in which an antistatic agent or a coating layer of nitrified cotton amide resin is further laminated may be used.
By laminating such a laminate substrate, it is possible to improve manufacturing efficiency and conveyance efficiency, and functionality (chemical resistance, electrical insulation, moisture resistance, cold resistance, workability, etc.) Can be obtained.
As a lamination | stacking aspect of the said laminate film, ONy / Al / PP, PET / ONy / Al / PP, ONy / Al / PVC is mentioned, for example.

[Composition of laminate packaging material]
The laminate packaging material of this embodiment is comprised from the said laminate film. In general, a laminate packaging material including an aluminum layer is not suitable for cold forming because the aluminum layer is easily broken by necking during cold forming. In this respect, according to the laminate packaging material of the present embodiment, the above-described ONy film has excellent drawability, so that it is possible to suppress the breakage of the aluminum layer during cold deep drawing, etc. The generation of pinholes in can be suppressed. Therefore, even when the total thickness of the packaging material is thin, a molded product having a sharp shape and high strength can be obtained.

  The laminate packaging material of this embodiment preferably has an overall thickness of the ONy film and other laminate base material of 200 μm or less. When the total thickness exceeds 200 μm, it becomes difficult to form the corner portion by cold forming, and it tends to be difficult to obtain a molded product having a sharp shape.

  The thickness of the ONy film in the laminate packaging material of this embodiment is preferably 5 μm or more and 50 μm or less, and more preferably 10 μm or more and 30 μm or less. Here, if the thickness of the ONy film is less than 5 μm, the impact resistance of the laminate packaging material tends to be low, and the cold formability tends to be insufficient. On the other hand, when the thickness of the ONy film exceeds 50 μm, it is difficult to obtain an effect of further improving the impact resistance of the laminate packaging material, which is not preferable because the total thickness of the packaging material is increased.

[Production equipment for biaxially stretched nylon film]
Next, a method for producing the biaxially stretched nylon film of the present embodiment will be described based on the drawings.
First, an apparatus for producing the biaxially stretched nylon film of this embodiment will be described with an example.
As shown in FIG. 1, the film manufacturing apparatus 100 includes an original fabric manufacturing apparatus 90 for manufacturing the original fabric film 1, a biaxial stretching apparatus (tubular stretching apparatus) 10 that stretches the original fabric film 1, and stretching. A first heat treatment device 20 (preheating furnace) that preheats a base film 2 that is folded later (hereinafter also simply referred to as “film 2”), a separation device 30 that separates the preheated film 2 into two upper and lower sheets, A second heat treatment device 40 that heat-treats (heat-set) the separated film 2, a tension control device 50 that applies tension to the film 2 from the downstream side when the film 2 is heat-set, and the film 2 is heat-set. And a winding device 60 for winding the biaxially stretched nylon film 3 (hereinafter also simply referred to as “film 3”).

As shown in FIG. 1, the raw fabric manufacturing apparatus 90 includes an extruder 91, a circular die 92, a water cooling ring 93, a stabilizer plate 94, and a pinch roll 95.
The tubular stretching device 10 is a device for producing a film 2 by biaxially stretching (bubble stretching) a tubular raw film 1 with the pressure of internal air. As shown in FIG. 1, the tubular stretching device 10 includes a pinch roll 11, a heating unit 12, a guide plate 13, and a pinch roll 14.
The first heat treatment apparatus 20 is an apparatus for preliminarily heat-treating the flat film 2. As shown in FIG. 1, the first heat treatment apparatus 20 includes a tenter 21 and a heating furnace 22.
As shown in FIG. 1, the separating device 30 includes a guide roll 31, a trimming device 32, separating rolls 33A and 33B, and grooved rolls 34A to 34C. Further, the trimming device 32 has a blade 321.

The second heat treatment apparatus 40 includes a tenter 41 and a heating furnace 42 as shown in FIG.
As shown in FIG. 1, the tension controller 50 includes guide rolls 51 </ b> A and 51 </ b> B and a tension roll 52.
As shown in FIG. 1, the winding device 60 includes a guide roll 61 and a winding roll 62.

[Production method of biaxially stretched nylon film]
Next, each process which manufactures a biaxially-stretched nylon film using this film manufacturing apparatus 100 is demonstrated in detail.

(Raw film production process)
As shown in FIG. 1, the raw material nylon resin is melt-kneaded by an extruder 91 and extruded into a tube shape by a circular die 92. The tubular molten resin is cooled by a water cooling ring 93. The raw film 1 is molded by rapidly cooling a molten nylon resin as a raw material by a water cooling ring 93. The cooled original film 1 is folded by the stabilizer 94. The folded original fabric film 1 is sent to the next biaxial stretching process by a pinch roll 95 as a flat film.

(Biaxial stretching process)
As shown in FIG. 1, the original film 1 manufactured by the original film manufacturing process is introduced into the apparatus as a flat film by a pinch roll 11. The introduced raw film 1 is bubble-stretched by being heated with infrared rays at the heating unit 12. Thereafter, the film 2 after being bubble-stretched is folded by the guide plate 13. The folded film 2 is pinched by the pinch roll 14 and sent to the next first heat treatment step as a flat film 2.

At this time, the draw ratios in the MD direction and the TD direction are each preferably 2.8 times or more. When either the MD direction or the TD direction draw ratio is less than 2.8 times, the impact strength tends to decrease, and there is a tendency for practical problems to occur.
Moreover, it is preferable that the difference (TD-MD) which subtracted the draw ratio of MD direction from the draw ratio of TD direction is 0.1 times or more, and more preferably 0.2 times or more and 0.8 times or less. Preferably, it is still more preferably 0.3 times or more and 0.8 times or less. If the value of TD-MD is less than the above lower limit, the deep drawability of the resulting film tends to be insufficient, and the thickness accuracy of the film tends to be lowered. In particular, when the value of TD-MD is 0.1 times or less, the stretching stability is inferior and the thickness accuracy of the film tends to be lowered. On the other hand, when the value of TD-MD exceeds the above upper limit, the deep drawability of the resulting film tends to be insufficient, and the stretching stability tends to decrease.

(First heat treatment process)
The film 2 sent from the biaxial stretching step is at or above the shrinkage start temperature of the film 2 and about 30 ° C. higher than the melting point of the film 2 while being gripped at both ends by clips (not shown) of the tenter 21. The film 2 is preheated at a low temperature or lower and sent to the next separation step.
The heat treatment temperature in the first heat treatment is preferably 120 ° C. or higher and 190 ° C. or lower, and the relaxation rate is preferably 15% or lower.
By this first heat treatment step, the crystallinity of the film 2 is increased, and the slipping property between the overlapping films is improved.

(Separation process)
As shown in FIG. 1, the flat film 2 sent through the guide roll 31 is cut into both ends by a blade 321 of a trimming device 32 and separated into two films 2A and 2B. And film 2A, 2B is isolate | separated, interposing air between film 2A, 2B by a pair of separation roll 33A, 33B located up and down apart. The incision of the flat film 2 may be performed so that a part of the ear is generated by positioning the blade 321 slightly inward from both ends, or by positioning the blade 321 in the fold portion of the film 2. , It may be performed so that the ear does not occur.
These films 2A and 2B are overlapped again by three grooved rolls 34A to 34C positioned in order in the film flow direction, and sent to the next second heat treatment step. In addition, these grooved rolls 34A to 34C are obtained by plating the surface after the grooved processing. A good contact state between the films 2A and 2B and the air can be obtained through the grooves.

(Second heat treatment process (heat setting process))
The overlapped films 2A and 2B are heat-treated at a temperature equal to or lower than the melting point of the resin constituting the film 2 and about 30 ° C. lower than the melting point while being gripped at both ends by clips (not shown) of the tenter 41. It is (heat-set) and becomes a biaxially stretched nylon film 3 (hereinafter also referred to as film 3) having stable physical properties, and is sent to the next winding step.
The heat treatment temperature in the second heat treatment (heat setting) is preferably 160 ° C. or higher and 215 ° C. or lower, and more preferably 165 ° C. or higher and 210 ° C. or lower. If the heat treatment temperature is less than the lower limit, the film shrinkage rate tends to increase and the risk of delamination tends to increase.On the other hand, if the upper limit is exceeded, the bowing phenomenon during heat setting increases, and the film is distorted. In addition, the density tends to be too high, the crystallinity becomes too high, and the film tends to be difficult to deform.
In addition, the relaxation rate at this time is preferably 15% or less.
A strong tension is applied to the films 2A and 2B in the heating furnace 42 by the tension control device 50 located on the downstream side.

(Winding process)
The film 3 heat-set in the second heat treatment step is wound as films 3A and 3B on the two winding rolls 62 via the guide roll 61 via the tension control device 50.

[Modification of Embodiment]
The aspect described above shows one aspect of the present invention, and the present invention is not limited to the above-described embodiment, and has the configuration of the present invention and can achieve the object and effect. It goes without saying that modifications and improvements within the scope are included in the content of the present invention. In addition, the specific structure and shape in carrying out the present invention may be used as other structures and shapes within the scope of achieving the object and effect of the present invention.

  For example, in this embodiment, the tubular method is adopted as the biaxial stretching method, but a tenter method may be used. Furthermore, the stretching method may be simultaneous biaxial stretching or sequential biaxial stretching.

EXAMPLES Next, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited at all by these examples. The characteristics in each example (dynamic viscoelastic temperature dispersion characteristics of the biaxially stretched nylon film and deep drawability of the laminate film) were evaluated by the following methods.
(I) Measurement of dynamic viscoelastic temperature dispersion characteristics A strip-shaped test piece having a length of 100 mm and a width of 2 mm is prepared, and the end of the test piece is lubricated so that the length of the test piece is 40 mm. Affixed to paper and left in a test room at a temperature of 23 ° C. (or −150 ° C.) and a humidity of 50% RH for 48 hours or more. Then, using this test piece non-resonant / forced vibration type device (Rheobibron DDV-II-EA / ORIENTEC), dynamic viscoelastic temperature dispersion characteristics (complex elastic modulus (E), phase Delay (δ)) was measured. And the value of the dynamic elastic modulus (E ') and b / a (%) in the temperature of 23 degreeC or -150 degreeC was calculated | required from the obtained measured value.
(Ii) Deep-drawing moldability The laminate film was cut to prepare a 120 × 80 mm strip piece as a sample. Using a 33 x 55 mm rectangular mold, press it with a surface pressure of 0.1 MPa, change the molding depth from 0.5 mm to 0.5 mm, and cold mold each 10 samples. (One-stage pull-in molding). The molding depth at which no pinhole was generated in any of the 10 samples in the aluminum foil was taken as the limit molding depth, and the molding depth was shown as an evaluation value. In addition, confirmation of the pinhole confirmed the transmitted light visually.
A: The limit molding depth is 7 mm or more.
○: The limit molding depth is 5 mm or more and less than 7 mm.
X: The limit molding depth is less than 5 mm.

[Example 1]
(Raw film production process)
As shown in FIG. 1, after Ny6 pellets were melt-kneaded at 270 ° C. in an extruder 91, the melt was extruded as a tubular film from a circular die 92, and then rapidly cooled with water (15 ° C.). Film 1 was produced.
What was used as Ny6 is Ube Industries, Ltd. nylon 6 [UBE nylon 1022FD (trade name), relative viscosity ηr = 3.5].
(Biaxial stretching process)
Next, as shown in FIG. 1, the raw film 1 is inserted between a pair of pinch rolls 11, and then heated by the heating unit 12 while a gas is being pressed into the film 1, and blown to the stretching start point to form bubbles. The biaxial stretching in the MD direction and the TD direction was performed by the tubular method by expanding and taking up with a pair of downstream pinch rolls 14. The magnification during this stretching was 3.0 times in the MD direction and 3.3 times in the TD direction.
(First heat treatment step and second heat treatment step)
Next, as shown in FIG. 1, the film 2 is subjected to heat treatment at a temperature of 165 ° C. by the first heat treatment device 20, and then passed through the separation device 30 and then heat treated at a temperature of 210 ° C. by the second heat treatment device 40. And heat fixed.
(Winding process)
Next, as shown in FIG. 1, the film 3 heat-set in the second heat treatment step is wound as two films 3 </ b> A and 3 </ b> B on two winding rolls 62 via a guide roll 61 via a tension control device 50. A biaxially stretched nylon film was produced. The thickness of the obtained biaxially stretched nylon film was 15 μm.
The dynamic viscoelastic temperature dispersion characteristics of the obtained biaxially stretched nylon film were measured. The obtained results are shown in Table 1.
(Production of laminate film)
The obtained biaxially stretched nylon film was used as a front substrate film, an aluminum foil having a thickness of 40 μm was used as an intermediate substrate, and a CPP film having a thickness of 60 μm was used as a sealant film to obtain a laminate film. The laminated film after dry lamination was aged at 40 ° C. for 3 days.
The deep drawability of the obtained laminate film was evaluated. The obtained results are shown in Table 1.

[Examples 2-6, Comparative Examples 1-4]
As Examples 2 to 6, a biaxially stretched nylon film and a laminate film were prepared in the same manner as in Example 1 except that the conditions were changed according to the production conditions shown in Table 1 (biaxial stretching method, stretching ratio and heat setting temperature). Manufactured.
The dynamic viscoelastic temperature dispersion characteristics of the obtained biaxially stretched nylon film were measured. The obtained results are shown in Table 1. Further, the deep drawability of the obtained laminate film was evaluated. The obtained results are shown in Table 1.
On the other hand, as Comparative Examples 1 to 4, biaxially stretched nylon films obtained by the method according to the biaxial stretching method shown in Table 1 were obtained, and the dynamic viscoelastic temperature dispersion characteristics were measured in the same manner as in Example 1. The obtained results are shown in Table 1. Moreover, the laminate film was produced using the biaxially-stretched nylon film of Comparative Examples 1-4, and the deep drawing moldability was evaluated similarly to Example 1. FIG. The obtained results are shown in Table 1.

As is clear from the results shown in Table 1, when the dynamic viscoelastic temperature dispersion characteristics (b / a (%) value) of the biaxially stretched nylon film satisfy the above conditions (Examples 1 to 6). It was confirmed that it had excellent deep drawability during cold forming.
On the other hand, when the dynamic viscoelastic temperature dispersion characteristic of the biaxially stretched nylon film does not satisfy the above conditions (Comparative Examples 1 to 4), deep drawing of a laminate film obtained using this biaxially stretched nylon film It was confirmed that the property was insufficient.

  The biaxially stretched nylon film of the present invention is, for example, an industrial field (such as a lithium battery packaging material mounted on an electric vehicle, a tablet-type terminal device, a smartphone, etc.), a pharmaceutical field (such as a PTP packaging material), and a daily necessities field. It can be suitably used as a packaging material that particularly requires impact resistance and pinhole resistance, such as packaging materials for liquid detergents (refillable packaging materials for liquid detergents) and packaging materials for foods (such as packaging materials for retort foods). . Further, the laminate packaging material of the present invention can be suitably used as a packaging material for cold molding that requires particularly excellent deep drawability.

    3, 3A, 3B ... Biaxially stretched nylon film

Claims (4)

A biaxial characteristic in which the value of b / a (%) is 46% or less, where a is a dynamic elastic modulus E ′ at −150 ° C. and b is a dynamic elastic modulus E ′ at 23 ° C. Stretched nylon film.   A laminate film, wherein the biaxially stretched nylon film according to claim 1 is laminated.   A laminate packaging material using the laminate film according to claim 2. A biaxially stretched nylon film manufacturing method for manufacturing the biaxially stretched nylon film according to claim 1,
A raw film manufacturing process for forming a raw film from the raw material,
A biaxial stretching step of biaxially stretching the raw film,
And a heat setting step of heat-setting the film after the biaxial stretching step by performing a heat treatment. A method for producing a biaxially stretched nylon film.