JP3242837B2 - Method for producing base film for photographic film - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a base film for a photographic film, and more particularly, to a method comprising polyethylene-2,6-naphthalenedicarboxylate as a main component and having excellent transparency and dimensional stability.
Of the photo film for the base film with good flatness
It relates to a manufacturing method .

[0002]

2. Description of the Related Art Photo films are used as roll films such as negative films which are mounted on a general camera and used for photographing, X-ray films, plate making films, and the like.
Some are used as sheet films such as cut films.

[0003] A triacetyl cellulose (hereinafter sometimes abbreviated as "TAC") film is mainly used as a base film of a roll film, and polyethylene terephthalate (hereinafter referred to as "PET") is used as a base film of a sheet film. ) Is mainly used.

[0004] TAC film has no optical anisotropy and high transparency, and further has relatively high water absorption as a plastic film. Has an excellent property of being eliminated (curl elimination property) due to rearrangement of molecular chains due to water absorption in the development processing.
However, with recent advances in downsizing of photographing devices, it is necessary to reduce the size of the patrone for storing photographic films, and to make the base film for photographic films thinner than before, It has been required that the mechanical strength and dimensional stability have sufficient performance even if the thickness is small. However, when the thickness of the TAC film is reduced, the mechanical strength is insufficient and the demand cannot be satisfied.

On the other hand, polyester films typified by PET have excellent mechanical properties, transparency, dimensional stability, heat resistance, and chemical resistance, so that they can be used for magnetic tapes, photographic films, electrically insulating films, It is used for many purposes such as packaging film and drawing film.

For a photographic film, a PET film is used as a base film for a sheet film.

However, when this PET film is used as a roll-shaped film, its ability to prevent the film from being curled (hereinafter referred to as "anti-curling property") is insufficient. Further, for a PET film, the curl can be eliminated by performing a heat treatment at a temperature below the glass transition point (hereinafter sometimes referred to as “Tg”) of the film, but depending on the temperature to which the photographic film is exposed in daily life. Easily disappears. Therefore, it is difficult to use the PET film as the base film of the roll film.

Accordingly, it has been proposed to use a film containing polyethylene naphthalenedicarboxylate (hereinafter sometimes abbreviated as "PEN") as a main component as a base film for photographic films. In the PEN film, the anti-curling property obtained by the heat treatment at a temperature equal to or lower than the Tg of the film is not lost by the temperature exposed in daily life.

However, the present inventors have found that simply heating a film by this method results in insufficient planarity of the film. Such poor flatness may cause uneven coating in the subsequent production of a photographic film, for example, when a photosensitive material is applied to a base film.

[0010]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-mentioned problems of the prior art, and to provide polyethylene-2,6-
An object of the present invention is to provide a production method capable of suitably producing a base film for a photographic film having excellent flatness and transparency containing naphthalenedicarboxylate as a main component.

[0011]

The inventors of the present invention have found that a non-uniform dimensional change of a film occurs due to a heat treatment for imparting an anti-curling property. The occurrence of poor flatness, the occurrence of poor flatness in the film, when the heat treatment is performed in a roll state, causes the adhesion of the films to each other, and the poor flatness of the film is further deteriorated. It has been found that when heat treatment is performed during the heat treatment, poor flatness due to adhesion between the films occurs when the film after the heat treatment is wound up. Further, the present inventors have found that a film having excellent color tone and transparency can be obtained by adjusting the phosphorus content of the film, thereby completing the present invention.

That is, according to the present invention, the phosphorus content is
15 ppm or more and 200 ppm or less, and the optical density Y
0.040-0.075, not embossed
The degree of stiffness between the films in the portion is 3 or less and 110
Longitudinal direction of film when kept at 24 ° C for 24 hours
At least two side portions of the name Ru biaxially oriented fill-time thermal shrinkage of polyethylene <br/> down-2,6-naphthalene dicarboxylate 0.25% or less as a main component in the (MD)
Difference in height between two or more embossing the height of the d Nbosu are present on a straight line intersecting at right angles the 10 to 30 [mu] m of the embossing to the longitudinal direction (MD) of the film is 5 [mu] m or less
Rolled up after embossing
At a temperature of 80 ° C. to Tg (glass transition point of the film)
A method for producing a base film for a photographic film, characterized by performing a treatment .

[Polyethylene-2,6-naphthalenedicarboxylate] The base film for a photographic film produced in the present invention is:
It comprises polyethylene-2,6-naphthalenedicarboxylate as the main component. As the "main component", a copolymer of ethylene-2,6-naphthalenedicarboxylate having at least 97 mol%, preferably at least 98 mol% of all repeating units is used. It is preferable that the content of ethylene-2,6-naphthalenedicarboxylate is 97 mol% or more of all the repeating units because the anti-curling property becomes good. Most preferably, it is a homopolymer of polyethylene-2,6-naphthalenedicarboxylate.

As the copolymerization component constituting the copolymer, a compound having two ester-forming functional groups in a molecule can be used. For example, oxalic acid, adipic acid,
Dicarboxylic acids such as phthalic acid, isophthalic acid, terephthalic acid, 2,7-naphthalenedicarboxylic acid, diphenyl ether dicarboxylic acid; oxycarboxylic acids such as p-oxybenzoic acid, p-oxyethoxybenzoic acid; Dihydric alcohols such as methylene glycol, tetramethylene glycol, hexamethylene glycol, cyclohexane methylene glycol, neopentyl glycol, diethylene glycol and the like can be preferably used.

The polyethylene-2,6-naphthalenedicarboxylate is obtained by blocking some or all of the terminal hydroxyl groups and / or carboxyl groups with a monofunctional compound such as benzoic acid or methoxypolyalkylene glycol. Alternatively, the copolymer may be a copolymer of a very small amount of an ester-forming compound having three or more functions such as glycerin and pentaerythritol within a range where a substantially linear polymer can be obtained.

[Additives] Additives such as stabilizers, lubricants, ultraviolet absorbers, flame retardants, and the like are added to the base film for photographic films produced in the present invention.
And a dye or the like.

In order to impart slipperiness to the film, it is preferable to contain a small proportion of inert fine particles. Examples of such inert fine particles include inorganic particles such as spherical silica, calcium carbonate, alumina, titanium dioxide, kaolin clay, barium sulfate, and zeolite, or organic particles such as silicon resin particles and crosslinked polystyrene particles. The inorganic particles are preferably synthetic products rather than natural products for reasons such as uniform particle size, and inorganic particles of any crystal form can be used.

The above-mentioned inert fine particles have an average particle size of 0.05.
It is preferably in the range of 1.5 μm. In particular, when the inert fine particles are inorganic particles, the average particle size is 0.1 to
It is preferably in the range of 0.8 μm, and 0.2 to 0.1 μm.
More preferably, it is 5 μm. When the inert fine particles are silicon resin particles, the average particle size is 0.1 to 1.5 μm.
It is preferably in the range of m. When the inert fine particles are crosslinked polystyrene particles, the average particle size is 0.1 to 1
It is preferably in the range of μm.

When the average particle size of the inert fine particles is smaller than 0.05 μm, the effect of improving the film's slipperiness, abrasion resistance or winding property is small, while the average particle size is 1.5 μm.
If it is larger than m, the transparency of the film is undesirably reduced.

The content of the inert fine particles is from 0.001 to 0.
Preferably it is 2% by weight. When the inert fine particles are inorganic particles, the content is more preferably 0.001 to 0.1% by weight, and particularly preferably 0.002 to 0.05% by weight. When the inert fine particles are silicon resin particles, the content is preferably 0.001 to 0.1% by weight,
0.001 to 0.02% by weight, especially 0.001 to
Preferably, it is 0.01% by weight. When the inert fine particles are crosslinked polystyrene particles, the content is preferably 0.001 to 0.05% by weight. If the amount of the inert fine particles is less than 0.001% by weight, the slipperiness of the film tends to be insufficient. On the other hand, if it exceeds 0.2% by weight, the film haze increases and the transparency becomes insufficient. Absent.

The timing of adding the inert fine particles is not particularly limited as long as it is a stage before the polyethylene-2,6-naphthalenedicarboxylate is formed. For example, the inert fine particles may be added at the polymerization stage. It may be added at the time.

[Optical Density] The base film for a photographic film of the present invention has an optical density Y of 0.040 to 0.075 measured in an unstained state using an optical densitometer manufactured by X-Rite.

When the optical density Y is smaller than the above lower limit, the light incident from the film edge easily passes through the inside of the film, and the effect of preventing the light piping phenomenon cannot be obtained. When the optical density is larger than the above upper limit, the yellowness of the base film becomes strong, and coloring for uniform light transmission in the visible region is performed. Therefore, the optical film has an unnecessarily high optical density and a low light transmittance, that is, an unnecessarily dark base film, which is not preferable as a photographic film base film.

When a polyester film is used as a base film for a photographic film, since the refractive index of the polyester film is higher than the refractive index of the photosensitive material or air, light entering from the edge of the film is generated at the interface between the base film and the photosensitive agent layer. Since light is easily reflected and also easily reflected at the interface between the film and the atmosphere, the light reaches the photosensitive agent layer at a portion distant from the edge portion, and has a disadvantage that a so-called light piping phenomenon (fog) is easily caused. In order to prevent such a phenomenon, a method of adding a dye is preferable. The dye is preferably one having excellent heat resistance at a film forming temperature and excellent compatibility with polyester. In view of the above, a dye having an anthraquinone skeleton is particularly preferable because of excellent heat resistance and compatibility. When the color density is measured in the visible light region using an optical densitometer manufactured by X-Rite, the dyeing density is at least 0.03 or more and 0.17 or less, and the value of Y as an indicator of yellow tint is obtained. Is preferably 0.075 or less,
More preferably, it is 0.065 or less. If the color density is lower than 0.03, the effect of preventing the light piping phenomenon is insufficient, which is not preferable. Further, if the color density exceeds 0.17, transparency as a photographic film base film is lost, which is not preferable. On the other hand, if the value of the color density Y exceeds 0.075, the base film has a strong yellow tint, and when an emulsion is applied to the film to form a photographic film, light transmission in the visible region is biased, which is not preferable. .

[Variation of Heat Shrinkage / MD Heat Shrinkage in Film Width Direction] The biaxially stretched polyethylene-2,6-naphthalenedicarboxylate film of the present invention comprises:
When the film is held at 110 ° C. for 24 hours, the heat shrinkage in the film longitudinal direction (MD direction) is 0.25% or less, and the difference between the maximum value and the minimum value of this heat shrinkage in the width direction (TD). (Maximum heat shrinkage of MD−Minimum heat shrinkage of MD) is preferably 0.10% or less. 11
When the heat shrinkage in the longitudinal direction of the film when held at 0 ° C. for 24 hours exceeds 0.25%, for example, when a heat treatment at Tg or less is performed during the film conveyance, the film rubs against the film conveyance roll, and In the case where the heat treatment at Tg or less is performed in the state of a wound roll, poor flatness due to adhesion or rubbing between films is not preferred. On the other hand, when the dispersion in the film width direction (difference between the maximum value and the minimum value of the heat shrinkage ratio) of the heat shrinkage ratio in the film longitudinal direction (MD) when kept at 110 ° C. for 24 hours exceeds 0.10%. When the film is heated at a temperature equal to or lower than Tg, sag occurs in the film, and when the film is subsequently wound up, adhesion and rubbing of the films occur to deteriorate the flatness of the film, which is not preferable.

The heat shrinkage in the longitudinal direction of the film when held at 110 ° C. for 24 hours is 0.25% or less, and the variation in the heat shrinkage in the film width direction is 0.1% or less. As a method for, for example, between the biaxially stretched, heat-fixed and wound around the roll, the film is transported on the heated transport roll, and the speed of the transport roll after the heated transport roll is reduced. A method of heating with an IR heater between conveyance rolls having different speeds, a method of cutting off both ends of a film in the middle of a heat fixing zone and reducing a take-off speed with respect to a supply speed of the film, and a method of blowing hot air after heat fixing. A method of lowering the take-up speed than the supply speed while transporting the film on the top, or winding the film with a film forming machine,
A method in which the film is conveyed onto a heating conveyance roll to reduce the speed of the conveyance roll until the heat treatment described below is performed, or the roll speed after the heating zone is heated while conveying the heating zone in a heating oven or an IR heater. There is a method of reducing the roll speed before the zone, etc., and any of these methods may be used. In addition, in the present invention, the range of the above-mentioned heat shrinkage and the variation of the heat shrinkage in the film longitudinal direction in the film width direction are used. However, the present invention is not limited to these as long as the heat-reducing treatment falls within the range described above.

The biaxially stretched polyethylene according to the present invention
The 2,6-naphthalenedicarboxylate film preferably has a heat shrinkage in the film width direction (TD direction) of 0.25% or less when the film is kept at 110 ° C. for 24 hours. The heat shrinkage can be reduced during the above-described process of reducing the heat shrinkage in the longitudinal direction of the film or by this method.

[Phosphorus Content] The base film for photographic films produced in the present invention contains polyethylene-2,6-naphthalenedicarboxylate as a main component, and the phosphorous content of the film is not less than 15 ppm and not more than 200 ppm as phosphorus atoms. More preferably, it is 25 ppm or more and 100 ppm or less, particularly preferably 35 ppm or more and 80 ppm or less.

When the phosphorus content of the film is less than 15 ppm, the reaction catalyst contained in the film is not sufficiently deactivated, the deterioration proceeds during heating and melting, and the yellow tint of the film increases. Lack of transparency.

On the other hand, when the phosphorus content of the film is 200 pp
If it exceeds m, the phosphorus compound itself is present as a foreign substance in the film, and becomes a nucleus for agglomerating a lubricant contained in the film to increase the haze of the film, which is not preferable for photographic applications. The haze of the film is preferably 2.0% or less for photographic use.

The phosphorus is preferably added at the time of polymerization of polyethylene-2,6-naphthalenedicarboxylate.

[Degree of Crisis] The degree of crispness between the film and the non-embossed portion of the base film for a photographic film produced in the present invention is preferably not more than grade 3, more preferably 2.5 grade. Or less, particularly preferably secondary or lower. The larger the grade of the degree of stiffness, the more difficult the film is to slip, and the smaller the grade, the more the films tend to slip. If the degree of stiffness is higher than the third grade, the slip between the films is poor, the sticking between the films occurs, and the flatness of the film is easily impaired. Sex is impaired. The details of the degree of sharpness will be described in Examples.

[Difference in Emboss Height / Emboss Height] The base film for a photographic film produced in the present invention comprises:
Embossing is applied to both ends of the film or one or more portions between the both ends and the intermediate portion. This embossing is performed continuously in the longitudinal direction of the film (MD direction). The embossing process may be applied to only the both ends of the film, or to both ends of the film and other parts, as long as care is taken so as not to hinder the undercoating or emulsion coating on the base film. There may be any number of places. The method of embossing is not particularly limited as long as it is a method of forming continuous irregularities by embossing or the like in the longitudinal direction (MD direction) of the film, and is shown in, for example, Japanese Patent Publication No. 47-1664. Methods and the like can be used.

The height of the emboss in the present invention is 10 to 3
0 μm. If the film is wound without embossing or wound with an excessively low emboss height, fine scratches occur due to blocking between the films and rubbing between the films, and heat treatment of the rolled film At this time, the flatness for photographic films becomes unsatisfactory because the flatness is poor due to blocking and the transfer of the core occurs due to tightening of the winding. On the other hand, if the height of the embossing is excessively large , these problems do not occur, but the roll appearance itself becomes unstable, and the roll shifts when winding the roll, the roll deforms when the roll is conveyed, and when the roll is heat-treated. Is undesirably deformed due to tight tightening. Details of the embossing height will be described in Examples.

Further, the embossing is performed in the longitudinal direction of the film (M
D) The difference between the heights of two or more embosses existing on a straight line perpendicular to the direction is 5 μm or less. Film when the difference between the embossed height was wound with the film into a roll excessively large twisted, wrinkles occur plane of the film you worse. Furthermore, the glass transition point (Tg) to (Tg-4) of polyethylene-2,6-naphthalenedicarboxylate is maintained while the roll is in a bad roll form.
0) when heated at ℃ temperature, deterioration of flatness because the film roll each portion wound tightly around the uneven that Do more remarkable.

[Base Film Thickness] The thickness of the base film for a photographic film of the present invention is in the range of 40 to 120 μm, preferably 50 to 100 μm. Thickness 4
If the thickness is less than 0 μm, the mechanical strength is insufficient, which is not preferable. On the other hand, if the thickness is more than 120 μm, it is not preferable because the film is not thinned.

[ANSI Curl Value] The base film for a photographic film of the present invention preferably has a property of hardly curling, that is, an anti-curling property. For example, the anti-curling property at 80 ° C. is 5 in ANSI curl value.
It is preferably 0 [m ^-1 ] or less. This 80 ° C.
It is an approximation of the highest temperature to which a photographic film can be normally exposed in daily life. ANSI curl value is 50
If it exceeds [m ^-1 ], it becomes difficult to handle in the photographic processing step, which is not preferable.

Conventionally, the evaluation of curling of a photographic film is as follows.
It depends on the extent to which the curl is eliminated through the usual photo film development or drying process. However, if the base film for a photo film has the above ANSI curl value, the curl of the curl is hard to occur. It has excellent properties, that is, anti-curling properties, and also has excellent curling-removing properties, in which curling once formed is easily resolved.

[Heat Treatment] The heat treatment of the present invention is carried out at 80 ° C. to T
Wound on a roll at a temperature of g (glass transition point of the film)
Perform in a state where When the heat treatment temperature is lower than 80 ° C., it takes an extremely long time for the heat treatment, and the production efficiency is deteriorated. On the other hand, when the heat treatment temperature exceeds the Tg of the film, the anti-curling property becomes inferior (the curl tends to be easily formed), which is not preferable as a photographic film base film.

Incidentally, the processing time of the heat treatment is preferably 1000 hours or less from the viewpoint of production efficiency.

[Production Method] The base film for a photographic film of the present invention can be advantageously produced by subjecting an unstretched film obtained by a usual method to biaxial stretching and heat setting, followed by relaxation treatment. For example, if the unstretched film is
g to (Tg + 60) ° C. in the vertical and horizontal directions at a temperature of 2.0 ° C.
It is biaxially stretched at 5.0 times, and (Tg + 50) ° C. to (Tg + 1
40) Heat set at 1 ° C. for 1-1000 seconds. After that, the film is subjected to relaxation treatment until it is wound on a roll. As a relaxation treatment method, both ends of the film are cut off in the middle of the heat setting zone and the film is supplied at a temperature of not less than Tg and not more than the melting temperature. A method in which the take-up speed is reduced, a method in which heating is performed by an IR heater between two transport rolls having different speeds, a method in which a film is transported on a heated transport roll and the speed of the transport roll after the heated transport roll is reduced, A method in which the film is conveyed over a nozzle that blows out hot air after heat fixation, while the take-up speed is slower than the supply speed, or after winding by a film forming machine, before performing heat treatment at Tg or less. A method in which the film is transported onto a heated transport roll and the speed of the transport roll is reduced, or a heating zone in a heating oven or an IR heater There is a method in which the roll speed after the heating zone is reduced from the roll speed before the heating zone while transporting the heat, and any method may be used. Perform the relaxation treatment at 1 to 10%. The present invention is not limited to these methods as long as the method falls within the above-mentioned range of the heat shrinkage and the range of the MD heat shrinkage in the width direction.

[0042]

The present invention will be described in more detail with reference to the following examples.

(1) Heat shrinkage ratio The sample is kept in hot air at 110 ° C. for 24 hours, and the dimensional change before and after this is determined by the following equation.

[0044]

## EQU1 ## Heat shrinkage = (L ₀ −L) × (1 / L) × 100 (%)

Here, L ₀ is the distance between the gauges before the thermal contraction, and L is the distance between the gauges after the thermal contraction.

(2) Degree of Hardness A rubber plate is laid on a flat table, and a film excluding two knurling portions, which does not contain dust and dirt, is placed between the films. A cylindrical weight having an outer diameter of 70 mm and a weight of 10 kg is gently placed on the film from directly above, and after 10 minutes, the weight is gently removed. After leaving for 30 seconds, the contact pattern in the circle of the cylindrical trace is photographed, the ratio of the area of the sharpness portion is measured, and the result is rated from Class 1 to Class 5 from Table 1 below.

[0047]

[Table 1]

(3) Anti-curling property (ANSI curl value) A sample film having a size of 120 mm × 35 mm was
Wound around a 7 mm diameter core, temporarily fixed so as not to unwind, heated at 80 ° C for 2 hours, released from the core,
Immerse in distilled water at 40 ° C. for 15 minutes. Next, a load of 33 g is applied, and the sample is suspended vertically and heat-treated at 55 ° C. for 3 minutes.

The sample in a state where the curl remains is subjected to AN
The measurement is carried out according to the test method A of SI PH 1.29-1971, and the curl value is calculated by changing inches to metric system.

(4) Measurement of Purity of Ethylene-2,6-Naphthalenedicarboxylate A film sample was measured with a solvent (CDCl ₃ : CF ₃ COO).
(D = 1: 1), and ¹ H-NMR measurement is carried out, and it is calculated by the integration ratio of each obtained signal.

(5) Flatness after heat treatment After heat treatment of the film, the flatness of the film (wrinkles, transfer, scratches due to rubbing, poor flatness due to film sticking, poor flatness due to roll deformation) is evaluated in three steps. I do. ：: good △: usable (partly defective) ×:
Usage prohibited

(6) Glass transition point (Tg) Differential scanning calorimeter DSC manufactured by Seiko Denshi Kogyo KK
The measurement is carried out under the following conditions using the sample No. 220. Heating rate: 20 ° C./min Sample amount: 10 mg Measured in a nitrogen stream Once heated and melted under the above conditions, rapidly cooled, and measured again under the above conditions.

(7) Color Density in Visible Light Region Using an optical densitometer 310TR manufactured by X-Rite, the color density of one film is measured by a transmission method.

(8) Emboss Height The thickness of the entire film (t ₁ ) including the embossed irregularities and the film thickness (t ₀ ) of the non-embossed portions near the embossed irregularities. The emboss height is calculated based on the difference.

[0055]

## EQU2 ## Emboss height (μm) = t ₁ −t ₀

(9) Haze value According to the method of JIS K-6714, the total haze value per film is measured with a commercially available haze meter.

Example 1 0.005% by weight of silica particles having an average particle diameter of 0.3 μm, 0.015% by weight of a dye, 60 ppm of phosphorus as a phosphorus atom, and an intrinsic viscosity of 0.6
Polyethylene-2,6-naphthalenedicarboxylate (PEN), which is 0, was melt-extruded through a die slit and cooled and solidified on a casting drum to prepare an unstretched film.

The unstretched film is successively biaxially stretched 3.0 times in the machine direction (machine direction) and 3.3 times in the transverse direction (width direction) and heat-fixed. Both ends of the film were cut off, and the take-up speed was reduced by 3% with respect to the feed speed of the film under a temperature condition of not less than Tg of the film and not more than the melting temperature, to obtain a biaxially oriented film having a thickness of 80 μm. After treating both sides of the biaxially oriented film so that the height of the embossment was 25 μm, the biaxially oriented film was wound around a roll. The difference in the height of each emboss present on a straight line intersecting at right angles to the film longitudinal direction (MD) was 3 μm. When the obtained biaxially oriented film was kept at 110 ° C. for 24 hours, the heat shrinkage was 0.20%, and the variation in the heat shrinkage in the film longitudinal direction (MD) in the film width direction was 0.1%. 05%.

From the obtained biaxially oriented film, a width of 1000
A sample film having a length of 2,000 m and a length of 2,000 mm was sampled and wound around a core having a diameter of 165 mm to form a sample roll. In this state, the temperature was raised to 110 ° C. over 24 hours, held for 24 hours, and then subjected to a heat treatment of lowering the temperature to room temperature over 24 hours to obtain a biaxially oriented film having a thickness of 80 μm.

After heat-treating the biaxially oriented film, the flatness of the film (wrinkles, transfer, scratches due to rubbing, poor flatness due to film sticking, poor flatness due to roll deformation) was evaluated in three stages (Good: good, poor) : Usable, ×: unusable). Table 2 shows the physical properties of the film before the heat treatment and the flatness of the film after the heat treatment.

Example 2 A film was formed in the same manner as in Example 1 except that the heat shrinkage after holding at 110 ° C. for 24 hours was 0.25%. Table 2 shows the results.

Example 3 In Example 1, the film was kept at 110 ° C. for 24 hours in the longitudinal direction of the film (MD).
Of heat shrinkage in film width direction is 0.10%
A film was formed in the same manner except that Table 2 shows the results.

[ Comparative Example 1 ] A film was formed in the same manner as in Example 1, except that the emboss height was 5 µm and the film was wound. Table 2 shows the results.

[ Comparative Example 2 ] A film was formed in the same manner as in Example 1 except that the height of the emboss was 40 µm and the film was wound. Table 2 shows the results.

Comparative Example 3 A film was formed in the same manner as in Example 1, except that the emboss height was changed to 10 μm and the film was wound. Table 2 shows the results.

Example 4 A film was formed in the same manner as in Example 1 except that the phosphorus content was changed to 25 ppm. Table 2 shows the results.

Example 5 A film was formed in the same manner as in Example 1 except that the phosphorus content was changed to 180 ppm. Table 2 shows the results.

Comparative Example 4 A film was formed in the same manner as in Example 1, except that the heat shrinkage after holding at 110 ° C. for 24 hours was 0.30%.
Table 3 shows the results. Abrasion occurred on the heat-treated film, and the flatness was unsatisfactory as a photographic film base film.

Comparative Example 5 The procedure of Example 1 was repeated, except that the variation in the heat shrinkage in the film longitudinal direction (MD) in the film width direction when held at 110 ° C. for 24 hours was 0.15%. Filmed. Table 3 shows the results. After the heat treatment, the film was sagged, and the films adhered to each other. The flatness was unsatisfactory as a photographic film base film.

Comparative Example 6 A film was formed in the same manner as in Example 1, except that the height of the emboss was 3 μm and the difference in the height of the emboss was 1 μm. Table 3 shows the results. Abrasion occurred on the film after the heat treatment, and the flatness was unsatisfactory as a photographic film base film.

[Comparative Example 7 ] A film was formed in the same manner as in Example 1 except that the height of the emboss was 50 µm and the film was wound. Table 3 shows the results.
Wrinkles were generated due to the poor roll form after the heat treatment, and the flatness was unsatisfactory as a photographic film base film.

Comparative Example 8 A film was formed in the same manner as in Example 1, except that the emboss height was changed to 15 μm and the film was wound. Table 3 shows the results. Twisted wrinkles were generated on the roll before the heat treatment, and wrinkles became more apparent after the heat treatment. It is not preferable as a base film for photographic films.

Comparative Example 9 A film was formed in the same manner as in Example 1, except that the phosphorus content was changed to 10 ppm. Table 3 shows the results. The film has a high yellow tint (color density Y), which is not preferable as a base film for photographic films.

Comparative Example 10 A film was formed in the same manner as in Example 1, except that the phosphorus content was changed to 230 ppm. Table 3 shows the results. The haze of the film is high, and the transparency is low as a photographic film base film, which is not preferable.

Comparative Example 11 After forming a film in the same manner as in Example 1, a heat treatment was performed at 150 ° C. Table 3 shows the results. It has poor anti-curling properties and is not preferred as a base film for photographic films.

Comparative Example 12 A film was formed in the same manner as in Example 1, except that polyethylene-2,6-naphthalenedicarboxylate having a purity of 90 mol% of ethylene-2,6-naphthalenedicarboxylate was used. Was done. Table 3 shows the results. It has poor anti-curling properties and is not preferred as a base film for photographic films.

[0077]

[Table 2]

[0078]

[Table 3]

────────────────────────────────────────────────── ─── Continued on the front page (51) Int.Cl. ⁷ Identification code FI B29L 7:00 B29L 7:00 (56) References JP-A-7-253638 (JP, A) JP-A 7-219131 (JP) , A) Japanese Patent Application Laid-Open No. 7-281356 (JP, A) Japanese Patent Publication No. 94-6023 (58) Fields investigated (Int. Cl. ⁷ , DB name) G03C 1/795 G03C 1/765

Claims (4)

(57) [Claims] (1) a phosphorus content of 15 ppm as a phosphorus atom;
Not less than 200 ppm and the optical density Y is 0.040 to 0.2.
075, between the unembossed parts of the film
24 degrees at 110 ℃
Heat shrinkage in film longitudinal direction (MD)
Height of at least d in the two side portions Nbosu of polyethylene-2,6-naphthalene dicarboxylate name Ru biaxially oriented fill beam as a main component is 1 but is not more than 0.25%
Emboss 0-30 μm in the longitudinal direction of the film (MD)
Embossed so that the difference in height of two or more embossments are present on a straight line intersecting at right angles is 5 [mu] m or less with respect to
And then wound on a roll at 80 ° C to Tg (f
Method of manufacturing a photographic film base film characterized in that a heat treatment at a temperature of glass transition point) of Irumu. 2. The photographic film base film according to claim 1, wherein a heat shrinkage in the film width direction when the film after the heat treatment is kept at 110 ° C. for 24 hours is 0.25% or less. Manufacturing method. 3. The method for producing a photographic film base film according to claim 1, wherein the anti-curling property at 80 ° C. after the heat treatment is 50 [m ⁻¹ ] or less in ANSI curl value . 4. according to any one of claims 1 to 3, a polyethylene-2,6-naphthalene dicarboxylate, characterized in that it contains at least 97 mol% of ethylene-2,6-naphthalene dicarboxylate units Manufacturing method of base film for photographic film .