JP2868695B2 - Polyethylene naphthalate film for photographic materials - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a polyethylene naphthalate film for photographic light-sensitive materials, and more particularly to a polyethylene naphthalate film for photographic light-sensitive materials having excellent transparency, hue, heat stability and curling resistance. About film.

[0002]

2. Description of the Related Art As a base film of a photographic light-sensitive material,
Conventionally, triacetate films have been widely used. This triacetate film has safety and environmental problems due to the use of an organic solvent in the production process. There are also disadvantages such as limitations on mechanical strength and dimensional stability. For this reason, polyethylene terephthalate film has come to be used partially as an alternative material. However, since curled curl remains strongly, handleability after development processing is poor, and its use range is limited.

[0003] Japanese Patent Application Laid-Open Nos. 53-146773 and 1-244446 propose modified polyethylene terephthalate films with improved water vapor permeability and water content. Although these are effective in terms of curling and curling, they have drawbacks such as deterioration of dimensional stability due to moisture absorption and increased deformation of the film end face due to lower glass transition temperature. It was not enough.

In particular, in recent years, the use of photographic materials has been diversified, and the speed of film transport during photography and the size of photographing apparatuses have been reduced. As a film for photographic materials, an excellent curl curl has been used. In addition to resolvability, performance such as strength, dimensional stability, and adaptability of thinning has been required. To meet these requirements, triacetate film and modified polyethylene terephthalate film cannot sufficiently cope with the demand, and a film for photographic light-sensitive materials having excellent characteristics is desired.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a polyethylene naphthalate film for photographic light-sensitive materials which has excellent transparency, hue, heat stability and curling resistance.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to:
According to the present invention, a film comprising polyethylene naphthalate having naphthalenedicarboxylic acid as a main acid component and ethylene glycol as a main glycol component, wherein the film is a manganese compound, a phosphorus compound, and manganese derived from an antimony compound, The film contains phosphorus and antimony in a ratio satisfying the following formulas (1) and (2) at the same time, and the film is dissolved in a 2: 3 mixed solvent of hexafluoroisopropanol and chloroform.
The transmittance (T ₄₀₀ ) of 400 nm wavelength light when dissolved at mg / ml is 95% / cm or more, and the difference between the transmittance (T ₄₀₀ ) and the transmittance of 420 nm wavelength light (T ₄₂₀ ). This is achieved by a polyethylene naphthalate film for photographic light-sensitive materials, wherein (ΔT) is 3% / cm or less.

[0007]

[Formula 2] 0.7 ≦ Mn ≦ 1.7 0.5 ≦ Mn / P ≦ 1.2 0.7 ≦ Sb ≦ 2.2 (where Mn is a manganese element moles of acid per component 10 ⁶ g, P is the number of moles of the acid component 10 ⁶ per g of the phosphorus element, Sb represents the number of moles of the acid component 10 ⁶ per g of antimony element.)

In the present invention, polyethylene naphthalate is a polyethylene naphthalate containing naphthalenedicarboxylic acid as a main acid component and ethylene glycol as a main glycol component.

The naphthalenedicarboxylic acid includes, for example, 2,6-naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid and the like. Of these, 2,6-naphthalene Dicarboxylic acids are preferred. If the main acid component is not naphthalenedicarboxylic acid, it is not preferable because, for example, the curl property when formed into a film becomes poor.

Other acid components include aromatic dicarboxylic acids (for example, terephthalic acid, isophthalic acid, diphenylethane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl ether dicarboxylic acid, diphenyl sulfone dicarboxylic acid, diphenyl ketone dicarboxylic acid, anthracene dicarboxylic acid, etc.). ); Aliphatic dicarboxylic acids (eg, adipic acid, sebacic acid, etc.); alicyclic dicarboxylic acids (eg, cyclohexane-1,4-dicarboxylic acid, etc.). The ratio of these other acid components is preferably 20 mol% or less based on the total acid components.

The glycol components other than ethylene glycol constituting the polyethylene naphthalate film include aliphatic glycols (for example, those having 3 to 3 carbon atoms such as trimethylene glycol, tetramethylene glycol, pentamethylene glycol, hexamethylene glycol, decamethylene glycol and the like). Polymethylene glycol, cyclohexanedimethanol, etc.); aromatic diols (eg, hydroquinone, resorcin, 2,2-bis (4-hydroxyphenyl) propane, etc.); polyalkylene glycols (polyoxyalkylene glycols)
(Eg, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, etc.). The proportion of these other glycol components is preferably 20 mol% or less based on all glycol components.

The polyethylene naphthalate used in the present invention is not limited to oxycarboxylic acids such as aromatic oxyacids such as hydroxybenzoic acid and aliphatic oxyacids such as ω-hydroxycaproic acid, as long as the effects of the present invention are not impaired. Derived components may be copolymerized or combined at 20 mol% or less based on the total amount of the dicarboxylic acid component and the oxycarboxylic acid component.

Further, the amount of polyethylene naphthalate in the present invention is in the range of a substantially linear range, and unless the effect of the present invention is impaired, for example, in an amount of 2 mol% or less based on the total acid components. Trifunctional or higher polycarboxylic acids or polyhydroxy compounds, such as trimellitic acid,
Pentaerthritol and the like can also be copolymerized.

The polyethylene naphthalate of the present invention may further include, for example, a lubricant, a pigment, a dye, an antioxidant, a light stabilizer, and a light-shielding agent as long as the surface flatness and thermal stability of the film are not impaired. Additives such as silica, cross-linked polystyrene, terazole blue, Irganox, cobalt, etc.) can be included as needed.

The polyethylene naphthalate film of the present invention can be produced by a conventional polyester production method, but it is produced by a transesterification method, ie, by reacting a lower alkyl ester of naphthalenedicarboxylic acid with ethylene glycol. Is preferred,
In this reaction, part of the lower alkyl ester of naphthalenedicarboxylic acid (for example, 20 mol% or less) may be substituted with another acid component, or part of glycol (for example, 2 mol% or less).
0 mol% or less) may be replaced with another glycol component.

The lower alkyl ester of naphthalenedicarboxylic acid includes, for example, dimethyl ester, diethyl ester, dipropyl ester and the like, and dimethyl ester is particularly preferred.

[0017] In the production of polyethylene naphthalate in the invention, the reaction of a lower alkyl ester and ethylene glycol naphthalene dicarboxylic acid, with respect to first acid component 10 ⁶ g, the element of manganese total 0.7
A soluble manganese compound is added to the reaction system in an amount of about 1.7 mol to perform a transesterification reaction. (Hereinafter, “mol” refers to the number of moles per 10 ⁶ g of the acid component.) Further, this amount is preferably 1.0 to 1.5 mol. When the amount of the manganese compound added to the acid component as the transesterification catalyst exceeds 1.7 mol, the surface flatness deteriorates when the film is formed due to the effect of precipitated particles due to the catalyst residue, and as a result, the transparency of the film Is not good and is not preferable. On the other hand, when the addition amount is less than 0.7 mol, not only the transesterification reaction becomes insufficient, but also the subsequent polymerization reaction is slow, which is not preferable.

Next, when the transesterification reaction is substantially completed, a phosphorus compound is added to deactivate a part of the transesterification catalyst. Is preferably 0.5 to 1.2. Particularly preferably, it is in the range of 0.6 to 1.1. When the molar ratio is less than 0.5, the surface flatness is deteriorated when the film is formed due to the influence of the precipitated particles due to the phosphorus catalyst residue. On the other hand, when the molar ratio exceeds 1.2, the phosphorus Due to the activity of the manganese compound that is not deactivated by the compound, the thermal stability of the polyethylene naphthalate deteriorates, and when formed into a film, the hue becomes unfavorable.

The manganese compound used in the present invention is not particularly limited, but is preferably an oxide, chloride, carbonate, carboxylate or the like, and particularly preferably an acetate, ie, manganese acetate.

Thereafter, the reaction product is subjected to a polycondensation reaction to form a polymer. An antimony compound is added to the reaction product as a main catalyst for the polycondensation reaction. The antimony compound may be added before the start of the transesterification reaction. Here, the amount of the antimony compound needs to be in the range of 0.7 to 2.2 mol as the antimony element amount. If the amount exceeds 2.2 moles, the precipitates caused by the antimony compound become unfavorable when the film is formed over a long period of time, because the precipitates are caused by film defects. On the other hand, when the addition amount is less than 0.7 mol, the polycondensation reactivity is poor,
This results in poor productivity, which is substantially undesirable.

The antimony compound used in the present invention is preferably an oxide, a chloride, a carbonate, a carboxylate, and the like. In particular, when acetate, that is, antimony acetate, is used, the precipitated particles in the polymer are smaller than those of other compounds. Less, film transparency is improved.

Examples of the phosphorus compound include trimethyl phosphate, triethyl phosphate, tri-n-butyl phosphate, phosphoric acid and the like. Preferred is trimethyl phosphate, but is not particularly limited.

In the present invention, the polyethylene naphthalate film is prepared by adding the film to a mixed solvent of hexafluoroisopropanol and chloroform in a 2: 3 mixed solvent of 10 mg / m 2.
1 and the transmittance of light having a wavelength of 400 nm (T
₄₀₀ ) must be at least 95% / cm, preferably at least 97% / cm. Further, the difference (ΔT) between the transmittance (T ₄₀₀ ) and the transmittance (T ₄₂₀ ) of light having a wavelength of 420 nm needs to be 3% / cm or less.

T ₄₀₀ and ΔT in the present invention are greatly affected by disturbances such as precipitated particles, lubricant particles, catalyst residues, crystallized substances, and foreign matters in the polyethylene naphthalate film, and furthermore, thermal deterioration during film forming. T ₄₀₀
Is less than 95% / cm, or ΔT exceeds 3% / cm, when used as a photographic base material, the light-sensitive condition at low wavelength light becomes poor, and when used as a color photographic film, the uneven color tone Is not preferred.

The polyethylene naphthalate film of the present invention is not particularly limited by the production method, and is preferably produced, for example, by the following method.

Polyethylene naphthalate has a melting point (Tm:
C) to (Tm + 60) ° C., extruded into a film, and quenched to obtain an unstretched film having an intrinsic viscosity of 0.5 dl / g or more (preferably 0.5 to 0.9 dl / g). The uniaxial direction (vertical or horizontal)
At a temperature of (Tg-10) to (Tg + 50) ° C (T
g: glass transition temperature of polyethylene naphthalate) 2
Then, the film is stretched at a magnification of up to 5 times, and subsequently in a direction perpendicular to the stretching direction (when the first-stage stretching is in the longitudinal direction, the second-stage stretching is in the transverse direction). 2 at temperature
Stretch at 5 times magnification. Thereafter, a heat setting treatment is further performed. This treatment is performed at (Tg + 60) ° C. or more (Tg + 12
0) It is preferably carried out at a temperature lower than 0 ° C. If the heat setting temperature is lower than (Tg + 60) ° C., the film is insufficiently crystallized, so that the curl recoverability becomes poor and the film is liable to peel off (delamid), and the peeled portion is not whitened. Further, problems such as delamination of layers at the time of forming perforation holes and growth of scratches caused by contact with metal or the like occur, which is not preferable. On the other hand, if the heat setting temperature is higher than (Tg + 120) ° C., the film is whitened due to excessive film crystallization, resulting in poor transparency, which is not preferable.

The thickness of the biaxially stretched film can be appropriately selected depending on the mode of use as a photographic light-sensitive material.
0 μm, more preferably 40 to 150 μm.

The polyethylene naphthalate film of the present invention may be provided with lubricity according to the application.
Means for imparting lubricity are not particularly limited, but the inclusion of inert particles in a polymer, or the application of a lubricating agent to a film is known as a general technique, and it is possible to use these. it can.

As a method for containing inert particles, S
iO ₂ , BaSO ₄ , CaCO ₃ , alumina silicate,
Examples thereof include a method in which crosslinked organic particles and the like are added to the polymer, and a method in which a catalyst and the like are precipitated during the polymerization of polyethylene naphthalate. From the viewpoint of securing the transparency of the film, the particles added from the outside preferably have a refractive index close to that of polyethylene naphthalate. For example, BaSO ₄ , alumina silicate, crosslinked organic particles (crosslinked polystyrene) And the like) are preferred.

Furthermore, when inert particles are contained, in order to obtain transparency of the film, a layer containing the inert particles on at least one surface of a polyethylene naphthalate film substantially free of particles is thinned. The method of laminating is also preferable. As this means, for example, a co-extrusion method using a plurality of extruders and feed blocks, or a multi-manifold die is mentioned as an effective means.

Since the polyethylene naphthalate film of the present invention has excellent transparency, hue, heat stability and curl resistance to curling, for example, a film for photography, a roll film for still photography, a roll film for movies, an X-ray film It can be used as a base film for a wide range of photographic applications such as roll films for film making and films for plate making.

[0032]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the examples without departing from the gist thereof. In the examples, "parts" means parts by weight. Further, the measurement of each characteristic value in the embodiment is performed by the following method.

(1) Transmitted light intensity at wavelengths of 400 nm and 420 nm (T ₄₀₀ , T ₄₂₀ ) 0.25 g of polyethylene naphthalate film is dissolved in a 2: 3 mixed solvent of hexafluoroisopropanol and chloroform to prepare a 25 ml solution. After (10 mg /
ml), Shimadzu self-recording spectrophotometer UV-3101P
The transmittance of light having a wavelength of 400 nm and 420 nm (T ₄₀₀ and T ₄₂₀ , unit =% / cm) is measured by C.

(2) Thermal Stability A thermal degradation index is obtained from the intrinsic viscosity of the polymer before and after the film is prepared using the following equation, and the thermal stability of the polymer is evaluated. Thermal degradation index = ([η ₀ ] / [η _x ]) − 1 where [η ₀ ]: intrinsic viscosity of polymer before film production [η _x ]: intrinsic viscosity of polymer after film production Judgment criteria: thermal degradation Index ≦ 0.05 Thermal stability ○ 0.05 <≦ ≦ 0.10 〃 △ 0.10 <〃 〃 ×

(3) Film Haze (Haze) Film haze is determined by an integrating sphere HTR meter manufactured by Nippon Seimitsu Kogaku Co., Ltd. in accordance with JIS-K6714. Judgment criteria: ○ ... good when haze is 2% or less △ ... haze 2 to 5% × ... use is limited when haze is 5% or more

(4) Curl recovery rate The sample film was cut into a size of 120 mm x 35 mm.
After winding in the longitudinal direction around a core with a diameter of 10 mm,
Time treated, then released from core. Thereafter, the sample is immersed in distilled water at 40 ° C. for 15 minutes, and the sample is hung vertically in a longitudinal direction, and dried in a 55 ° C. air thermostat under a load of 5 g for 3 minutes. Subsequently, the distance (A: mm) between the upper end and the lower end of the film is obtained except for the load. The curl recovery rate is represented by the following equation.

[0037]

(Equation 3)

(5) Glass transition temperature Differential calorimeter (Du Pont DSC2100)
The glass transition peak temperature is determined at a heating rate of 20 ° C./min.

Example 1 100 parts of 2,6-naphthalenedicarboxylic acid dimethyl ester and ethylene glycol 6
0 parts were subjected to a transesterification reaction using 0.03 parts (1.23 mol) of manganese acetate tetrahydrate as a transesterification catalyst in a conventional manner, and then 0.023 parts (1.64 parts) of trimethyl phosphate. Mol) was added to substantially terminate the transesterification reaction.

Further, 0.024 parts of antimony trioxide (0.
(82 mol), followed by a polycondensation reaction in the usual manner under high temperature and high vacuum to obtain polyethylene naphthalate having an intrinsic viscosity (o-chlorophenol, 35 ° C) of 0.62 dl / g.

The polyethylene naphthalate pellets were dried at 180 ° C. for 3 hours and then supplied to an extruder hopper.
Melted at a melting temperature of 300 ° C.
Through a slit die on a rotary cooling drum having a surface temperature of 40 ° C. to obtain an unstretched film. The unstretched film thus obtained is preheated to 120 ° C., further heated by a single IR heater having a surface temperature of 900 ° C. from 15 mm above between low-speed and high-speed rolls and stretched 3.0 times. Subsequently, the mixture was supplied to a stenter and stretched 3.3 times in the transverse direction at 140 ° C. The obtained biaxially oriented film was
This was heat-set at a temperature of 0 ° C. for 5 seconds to obtain a 75 μm-thick polyethylene naphthalate film. The intrinsic viscosity of this film was 0.60 dl / g.

The obtained film was heat-treated at 100 ° C. for 2 days, and the film characteristics were measured. As shown in Table 1, it was good.

Example 2 The procedure of Example 1 was repeated except that the amount of catalyst Mn was 0.80 mol and P was 1.07 mol. In this case, the transesterification reaction time and the polymerization reaction time were longer than in Example 1, but there was no problem in the physical properties of the obtained polyethylene naphthalate, and the film characteristics were good as shown in Table 1.

Example 3 The procedure of Example 1 was repeated except that the amount of catalyst Mn was 1.60 mol and the amount of P was 2.13 mol. In this case, although the T ₄₀₀ and the transparency is decreased as compared with Example 1, the film properties as shown in Table 1, could be used as a photographic film base material.

Examples 4 and 5 The same procedures as in Example 1 were carried out except that the catalyst ratio was changed to 1.10 or 0.58. In this case, although the T ₄₀₀ and the transparency is decreased as compared with Example 1, the film properties as shown in Table 1, could be used as a photographic film base material.

[Examples 6 and 7] Antimony trioxide was added as follows.
The same operation as in Example 1 was carried out except that the amount was 06 or 0.40 mol. In this case, the polymerization reaction time was longer than that of Example 1, but as shown in Table 1, the film was usable as a photographic film substrate.

Example 8 A film was obtained in the same manner as in Example 1 except that antimony acetate was used as a polymerization catalyst. As shown in Table 1, each property of the film was good, and the effect of improving the film hue and transparency was confirmed.

Example 9 A film was obtained in the same manner as in Example 2 except that the heat setting temperature of the biaxially oriented film was 190 ° C. Each characteristic of the film is shown in Table 1.
All were good, and the effect of improving the film hue and transparency as compared with Example 2 was confirmed.

Example 10 Example 3 was repeated except that the intrinsic viscosity of polyethylene naphthalate was changed to 0.52 dl / g.
A film having an intrinsic viscosity of 0.50 dl / g was obtained. Although this film was slightly inferior in curl recovery, it could be used as a photographic film substrate. Table 1 shows the properties of the film.

Example 11 100 parts of 2,6-naphthalenedicarboxylic acid and 50 parts of ethylene glycol were subjected to a direct esterification reaction under pressure using 0.02 parts (0.82 mol) of manganese acetate tetrahydrate. , Trimethyl phosphate (0.015 part, 1.09 mol), and antimony trioxide (0.024 part), and then a polycondensation reaction under high temperature and high vacuum to obtain an intrinsic viscosity (o-chlorophenol, (35 ° C.) 0.62 dl / g of polyethylene naphthalate was obtained. Thereafter, the same procedure as in Example 1 was performed,
As shown in Table 1, the properties of the obtained film were as good as those of Example 1.

Comparative Example 1 The procedure of Example 9 was repeated, except that the catalyst amount Mn was changed to 1.84 mol. Catalyst ratio Mn /
Since P was set to 0.75, the thermal stability of polyethylene naphthalate was within the usable range, but the transparency when formed into a film was poor due to an excessive manganese compound. Table 1 shows the film characteristics.

Comparative Example 2 The same operation as in Example 9 was carried out except that the catalyst amount Mn was changed to 0.65 mol. In this case, since the transesterification reaction becomes poor, the intrinsic viscosity does not increase even in the polymerization step, the curl recovery of the film is impaired, and the characteristics required for the film for photographic materials can be satisfied. Did not. Table 1 shows the film characteristics.

Comparative Example 3 The catalyst ratio Mn / P was 0.49.
The procedure was performed in the same manner as in Example 9 except for the above. Addition of excess phosphorus compound, the thermal stability of the polyethylene naphthalate is degraded, T _{40 0} was poor transparency of the case where the causes decreased, also the film. Table 1 shows film characteristics
Shown in

[Comparative Example 4] The catalyst ratio Mn / P was 1.23.
The procedure was performed in the same manner as in Example 9 except for the above. The manganese compound which is not deactivated by phosphorus compounds, deteriorates the thermal stability of the polyethylene naphthalate, will be reduced the same T ₄₀₀ as Comparative Example 3 was poor transparency of the case of the film. Table 1 shows the film characteristics.

Comparative Example 5 A film was obtained in the same manner as in Example 9 except that the heat setting temperature of the biaxially oriented film was set at 250 ° C. As shown in Table 1, the properties of the obtained film were poor in T ₄₀₀ , ΔT, and film transparency.

Comparative Example 6 A film was obtained in the same manner as in Example 9 except that the heat setting temperature of the biaxially oriented film was 170 ° C. In this case, T ₄₀₀ , Δ
T and the transparency of the film were good, but the curl recovery was poor, and the characteristics required for a film for a photographic material could not be satisfied.

Comparative Example 7 A film was obtained in the same manner as in Example 9 except that the amount of antimony acetate was changed to 2.30 mol. The film was poor in thermal stability, _T400 was lowered, and the characteristics required for a film for a photographic material could not be satisfied.

[0058]

[Table 1]

[0059]

According to the present invention, excellent hue, transparency,
A polyethylene naphthalate film useful as a film for a photographic light-sensitive material having both heat stability and curling resistance can be provided.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G03C 1/795 G03C 1/81 G08G 63/189

Claims (4)

(57) [Claims] 1. A film comprising polyethylene naphthalate containing naphthalenedicarboxylic acid as a main acid component and ethylene glycol as a main glycol component, wherein the film is derived from a manganese compound, a phosphorus compound, and an antimony compound. , And antimony in a ratio satisfying the following formulas (1) and (2) at the same time, and adding the film to a 2: 3 mixed solvent of hexafluoroisopropanol and chloroform.
The transmittance (T ₄₀₀ ) of 400 nm wavelength light when dissolved at mg / ml is 95% / cm or more, and the difference between the transmittance (T ₄₀₀ ) and the transmittance of 420 nm wavelength light (T ₄₂₀ ). A polyethylene naphthalate film for a photographic light-sensitive material, wherein (ΔT) is 3% / cm or less. [Formula 1] 0.7 ≦ Mn ≦ 1.7 0.5 ≦ Mn / P ≦ 1.2 0.7 ≦ Sb ≦ 2.2 (where Mn is a manganese element moles of acid per component 10 ⁶ g, P is the number of moles of the acid component 10 ⁶ per g of the phosphorus element, Sb represents the number of moles of the acid component 10 ⁶ per g of antimony element.) 2. The polyethylene naphthalate film for a photographic light-sensitive material according to claim 1, wherein the polyethylene naphthalate is polyethylene-2,6-naphthalate produced by a transesterification method. 3. The polyethylene naphthalate film for a photographic light-sensitive material according to claim 1, wherein the antimony compound is antimony acetate. 4. The heat fixation of the polyethylene naphthalate film after biaxial stretching is performed at (Tg + 60) ° C. or higher (Tg + 12
0) The polyethylene naphthalate film for a photographic light-sensitive material according to claim 1, wherein the film is formed at a temperature lower than 0 ° C (where Tg is the glass transition temperature (° C) of polyethylene naphthalate).