JPH08328198A - Base material for photograph - Google Patents

Abstract

PURPOSE: To provide a base material for photograph which reduces uniformity of the coating thickness distribution in the both ends in the coating width direction in coating photograph constitution layers such as an under coating layer, a back layer, a photograph emulsion layer, etc., is superior in pre-splice conveyance, and is composed of a biaxially oriented polyester film. CONSTITUTION: The base material for photograph composed of a biaxially oriented polyester film whose glass transition temperature is Tg, is so formed that, after a film is heat-treated in the range of (Tg-30 deg.C) to Tg for preventing winding inclination after forming the film, the end part in the vertical coating width direction in relation to the conveyance direction in the case of coating the film is heat-treated in the range of Tg to (Tg+130 deg.C) during the period before a photograph constitution layer is applied on the film.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic support comprising a biaxially stretched polyester film which is excellent in transparency and mechanical strength and has a reduced curl curl, and in particular, an undercoat layer, a back layer and a photographic emulsion. The present invention relates to a photographic support comprising a biaxially stretched polyester film in which unevenness of coating thickness distribution at both ends in the coating width direction when coating a photographic constituent layer such as a layer is reduced.

[0002]

2. Description of the Related Art In recent years, the use of photographic light-sensitive materials has been diversified, and the speed of film unwinding at the time of photographing, the increase of photographing magnification, and the downsizing of photographing apparatus have been remarkably advanced. Therefore, a support for a photographic light-sensitive material is required to have properties such as excellent mechanical strength and dimensional stability. Further, the roll film-shaped photographic light-sensitive material is required to have a smaller diameter core.

A triacetyl cellulose film (hereinafter referred to as a TAC film) has been conventionally used as a roll film type photographic light-sensitive material such as a general color negative film. However, the TAC film has a small mechanical strength and has a large dimensional change due to moisture absorption, so that the film cannot be thinned. Further, the curl curl increases by reducing the diameter of the winding core. For this reason, there is a new problem of conveyance failure in the press-price process before the development process. In other words, in a large-scale processing lab, it is normal to process several photographic films that have already been taken, one by one, by joining them together to make them long, and then processing them all at once. If the curl of the photographed photographic film is too large, the joining of the photographic films becomes difficult.

Biaxially stretched polyethylene terephthalate film (hereinafter referred to as PET film) has excellent transparency,
A microfilm that has mechanical strength and dimensional stability and requires thinning of the film, a printing sensitive material that requires strict dimensional stability, and a film for X-ray that requires transparency and elasticity. Used in. However, PET
The film does not have the curl curl recovery after development processing as seen in TAC film, and when used in roll film photographic photosensitive materials, curl curl after development processing is too large and handling during sorting is easy. Not only is it inferior to, but, for example, in the process of printing an image on photographic printing paper after development,
There are problems such as scratches, defocusing, and jamming during transportation. Further, the PET film is superior to the TAC film in that it has less winding tendency, but it cannot be said to be sufficient when the diameter of the winding core is reduced.

Generally, polyester films are excellent in mechanical strength and dimensional stability. Therefore, by reducing the curl curl of the polyester film typified by the PET film, the curl curl after the development processing can be reduced, and the various problems described above can be solved.

From such a viewpoint, the open technical report 94-602
No. 3 proposes a technique for reducing the curl by heat-treating a polyethylene naphthalene dicarboxylate film (hereinafter referred to as PEN film) at a glass transition temperature (hereinafter referred to as Tg) or lower.

[0007]

[Problems to be Solved by the Invention]
In a PEN film that has been subjected to a heat treatment of g or less,
On the other hand, there is a problem that the coating thickness distribution is large at both end portions in the coating width direction when a photographic constituent layer such as an undercoat layer, a back layer, a photographic emulsion layer, etc. is coated although it is hard to have a curl.

That is, these photographic constituent layers are applied while the film is conveyed by a plurality of roll groups.
The PEN film that has been subjected to a heat treatment of g or less has a high rigidity because the molecular structure of the PEN film is transformed into an equilibrium state in which the free volume is sufficiently small, and even if the film is held in a roll, it does not adhere uniformly. It floats and sticks repeatedly. Therefore, there is a drawback that the gap between the film and the coater becomes non-uniform and the coating thickness distribution becomes large, and it has been found that such a phenomenon is particularly remarkable at the end portion of the film. Such non-uniformity of the coating thickness distribution causes unevenness in quality when the product is formed, so that the film edge cannot be used for the product and the productivity is remarkably deteriorated.

In view of the above situation, the problem that the coating thickness distribution at both ends in the coating width direction becomes large due to the heat treatment of Tg or less applied to prevent the curl of the PEN film becomes large, and the unevenness of quality is solved. There has been a demand for a technique for improving the productivity and improving the productivity.

Therefore, an object of the present invention is to reduce the unevenness of the coating thickness distribution at both ends in the coating width direction when coating a photographic constituent layer such as an undercoat layer, a back layer, a photographic emulsion layer,
Another object of the present invention is to provide a photographic support made of a biaxially stretched polyester film having excellent press-price transportability.

[0011]

The above objects of the present invention have been achieved by the following constitutions.

(1) In a photographic support comprising a biaxially stretched polyester film having a glass transition temperature of Tg, the film is formed at a temperature of (Tg-30 ° C.) or more to prevent curl after formation of the film. After the heat treatment in the following range and before the film is coated with the photographic constituent layer, the end in the coating width direction perpendicular to the transport direction at the time of coating the film is Tg or more, (Tg + 130 ° C.) A photographic support characterized by being heat-treated in the following range.

(2) In the method for producing a photographic support comprising a biaxially stretched polyester film having a glass transition temperature of Tg, the film is formed (Tg-30 ° C.) to prevent curl after formation. As described above, after the heat treatment in the range of Tg or less and before the photographic constituent layer is applied to the film, Tg or more at the end in the application width direction perpendicular to the transport direction during application of the film, ( Tg + 130
C.) A method for producing a photographic support, which comprises performing heat treatment in the following range.

(3) The photographic support as described above, wherein the biaxially stretched polyester film contains an ethylene-2,6-naphthalene dicarboxylate unit in an amount of 70% by weight or more.

(4) The method for producing a photographic support as described above, wherein the biaxially stretched polyester film contains 70% by weight or more of ethylene-2,6-naphthalene dicarboxylate unit.

In the present invention, both ends in the coating width direction of the biaxially stretched polyester film used as a photographic support are at or above the temperature at the time of first heat treatment, that is, at or above Tg.
By adopting a technique of performing heat treatment in the range of (Tg + 130 ° C.) or less, unevenness of coating thickness distribution at both ends in the coating width direction caused by the first heat treatment performed for the purpose of reducing winding tendency. It has a remarkable effect of reducing the height.

The present invention will be described in detail below.

The polyester constituting the biaxially stretched polyester film of the present invention is not particularly limited, but is preferably a polyester having a dicarboxylic acid component and a diol component as main constituents and having film-forming properties. .

The main constituent dicarboxylic acid components include terephthalic acid, isophthalic acid, phthalic acid and 2,6-
Naphthalenedicarboxylic acid, 2,7-naphthalenedicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenyletherdicarboxylic acid, diphenylethanedicarboxylic acid,
Examples thereof include cyclohexane dicarboxylic acid, diphenyl dicarboxylic acid, diphenyl thioether dicarboxylic acid, diphenyl ketone dicarboxylic acid, phenylindane dicarboxylic acid and the like.

As the diol component, ethylene glycol, propylene glycol, tetramethylene glycol, cyclohexanedimethanol, 2,2-bis (4
-Hydroxyphenyl) propane, 2,2-bis (4-
Examples thereof include hydroxyethoxyphenyl) propane, bis (4-hydroxyphenyl) sulfone, bisphenol full orange hydroxyethyl ether, diethylene glycol, neopentyl glycol, hydroquinone and cyclohexanediol.

Among the polyesters containing these as the main constituents, terephthalic acid and / or 2,6-naphthalenedicarboxylic acid and diol are used as the dicarboxylic acid component from the viewpoints of transparency, mechanical strength, dimensional stability and the like. Polyesters whose main constituents are ethylene glycol and / or 1,4-cyclohexanedimethanol are preferred. Among them, polyesters containing polyethylene terephthalate or polyethylene-2,6-naphthalenedicarboxylate as a main constituent, copolymerized polyesters composed of terephthalic acid, 2,6-naphthalenedicarboxylic acid and ethylene glycol, and polyesters of these two Polyesters whose main constituent is a mixture of one or more kinds are preferred. Ethylene-2 for polyester
When the content of the 6-naphthalene dicarboxylate unit is 70% by weight or more, a film having excellent transparency, mechanical strength, dimensional stability and the like can be obtained. It is well known that a film containing polyethylene-2,6-naphthalenedicarboxylate as a main constituent is superior to a film containing polyethylene terephthalate as a main constituent in mechanical strength and heat resistance.

On the other hand, the film containing polyethylene-2,6-naphthalene dicarboxylate as a main constituent component,
There are disadvantages such as the property of emitting fluorescence and the high price of resin. Therefore, a film containing polyethylene terephthalate as a main constituent is usually used depending on the purpose for which it is used, and polyethylene-2,6 is used particularly when highly thinning is required or when the film is abused at a high temperature. -A film containing naphthalene dicarboxylate as a main constituent may be used. Further, by mixing the two, the drawbacks of each other can be compensated.

The polyester constituting the biaxially stretched polyester film of the present invention may be copolymerized with other copolymerization components as long as the effects of the present invention are not impaired, and other polyesters may be mixed. It may be done. Examples of these include the above-mentioned dicarboxylic acid component and diol component, or polyesters composed thereof.

The polyester constituting the biaxially stretched polyester film of the present invention contains an aromatic dicarboxylic acid having a sulfonate group or an ester-forming derivative thereof and a dicarboxylic acid having a polyoxyalkylene group in order to prevent delamination of the film. You may copolymerize an acid or its ester forming derivative, the diol which has a polyoxyalkylene group, etc. Among them, 5-sodium sulfoisophthalic acid, 2-sodium sulfoterephthalic acid,
4-sodium sulfophthalic acid, 4-sodium sulfo-2,6-naphthalenedicarboxylic acid and compounds obtained by substituting these sodium with other metals (for example, potassium, lithium, etc.), ammonium salts, phosphonium salts, etc., or ester forming properties thereof Derivatives, polyethylene glycol, polytetramethylene glycol, polyethylene glycol-polypropylene glycol copolymers, and compounds having carboxyl groups obtained by oxidizing the hydroxy groups at both ends thereof are preferable. The proportion of copolymerization for this purpose is preferably 0.1 to 10 mol% based on the difunctional dicarboxylic acid constituting the polyester.

For the purpose of improving the heat resistance of the film, a bisphenol compound, a compound having a naphthalene ring or a cyclohexane ring can be copolymerized.
The copolymerization ratio of these is preferably 1 to 20 mol% based on the difunctional dicarboxylic acid constituting the polyester.

The above-mentioned polyester may contain an antioxidant, and the effect becomes remarkable especially when the polyester contains a compound having a polyoxyalkylene group.

The type of the antioxidant to be contained is not particularly limited, and various antioxidants can be used. For example, antioxidants such as hindered phenol compounds, phosphite compounds, thioether compounds, etc. Can be mentioned. Among them, antioxidants of hindered phenolic compounds are preferable in terms of transparency.

The content of the antioxidant is usually 0.01 to 2% by weight, preferably 0.1 to 2% by weight with respect to the polyester.
0.5%. By setting the content of the antioxidant within this range, it is possible to prevent the so-called fog phenomenon in which the density of the unexposed portion of the photographic light-sensitive material becomes high, and the haze of the film can be suppressed to a low level, resulting in a highly transparent photograph. A support for use is obtained. These antioxidants may be used alone or in combination of two or more.

The above polyester preferably contains a dye for the purpose of preventing the light piping phenomenon. The dye to be blended for such a purpose is not particularly limited in its type, but in the production of the film,
It is necessary to have excellent heat resistance, and examples thereof include anthraquinone dyes and perinone dyes. Further, as the color tone, gray dyeing is preferable as seen in general photographic light-sensitive materials. Examples of these dyes include MA manufactured by Bayer.
CROLEX series, SUMI made by Sumitomo Chemical Co., Ltd.
PLAST series, Mitsubishi Kasei Corporation Diare
From the sin series and the like, one kind can be used alone, or two or more kinds of dyes can be mixed and used so as to obtain a necessary color tone. At this time, the film has a spectral transmittance of 400 to 70.
60% to 85% in the wavelength range of 0 nm, and 6
It is preferable to use the dye so that the difference between the maximum and the minimum of the spectral transmittance is 10% or less in the wavelength range of 00 to 700 nm in order to prevent the light piping phenomenon and obtain a good photographic print.

The biaxially stretched polyester film of the present invention may be provided with slipperiness, if necessary. The means for imparting slipperiness is not particularly limited, but an external particle addition method of adding inert inorganic particles to polyester, an internal particle precipitation method of precipitating a catalyst added at the time of polyester synthesis, or a surfactant film The method of applying on the surface is common. Among these, the internal particle deposition method in which the deposited particles can be controlled to be relatively small is preferable because slipperiness can be imparted without impairing the transparency of the film. As the catalyst, various known catalysts can be used, but Ca and Mn are particularly preferable because high transparency can be obtained. These catalysts may be one kind,
You may use 2 or more types together.

The biaxially stretched polyester film may have a multilayer structure composed of different kinds of polyester. For example,
Ethylene terephthalate unit or ethylene-2,6
-When the layer made of a polyester having a naphthalene dicarboxylate unit as a main constituent is the A layer and the layer made of another polyester is the B layer or the C layer, a two-layered structure made of the A layer and the B layer may be used. , A layer / B layer / A layer, A
Layer / B layer / C layer, B layer / A layer / B layer or B layer / A layer / C
A three-layer structure such as a layer may be used. Further, a structure having four or more layers is of course possible, but it is not preferable in practice because the manufacturing equipment becomes complicated.

The thickness of the layer A is preferably 30% or more, and more preferably 50% or more of the total thickness of the polyester film.

As the polyester constituting the B layer or the C layer, polyethylene terephthalate, polyethylene naphthalene dicarboxylate or other homopolyester or other copolyester which is excellent in transparency, mechanical strength and dimensional stability is used. As a result, the transparency, mechanical strength, dimensional stability, etc. of the entire film can be improved.

Further, when the biaxially stretched polyester film has a multi-layered structure, the functions such as the above-mentioned oxidation prevention, light piping prevention, slipperiness, etc., or addition of various additives other than the above is added only to the surface layer. Since it can be performed, the transparency of the film can be maintained high.

The method for synthesizing the polyester as the raw material for the biaxially stretched polyester film is not particularly limited, and the polyester can be produced by a conventionally known method for producing polyester. For example, a direct esterification method in which a dicarboxylic acid component is directly esterified with a diol component, first a dialkyl ester is used as a dicarboxylic acid component, and an ester exchange reaction is performed between this and the diol component, and this is heated under reduced pressure. A transesterification method in which the excess diol component is removed to perform polymerization can be used. At this time, if necessary, a transesterification catalyst or a polymerization reaction catalyst may be used, or a heat stabilizer may be added.
Further, in each process during synthesis, anti-coloring agent, antioxidant, crystal nucleating agent, slip agent, stabilizer, anti-blocking agent, ultraviolet absorber, viscosity modifier, defoaming agent, clarifying agent, antistatic agent, p
An H regulator, a dye, a pigment and the like may be added.

The biaxially stretched polyester film of the present invention has a curl curl of 110 as determined by the following method.
It is preferably m ⁻¹ or less. If the curling curl of the film is too large, the transportability in the press-price process and the workability during sorting work will be poor. Further, it is preferable that the curling curl is moderate because it makes it easier to eject the leading end of the film from the film cartridge, that is, it is excellent in the tongue-out property. Therefore, the more preferable range of the curl curl of the film is 5 to 90 m ^-1 .

<Curl curl> Width 35 mm, length 1200
A photographic light-sensitive material having a size of mm is conditioned for one day under the conditions of 23 ° C. and 55% RH, and then fixed so that the photographic light-sensitive layer side is an inner side and is not wound around a core having a diameter of 7 mm.
Next, this film is put in a polyethylene cartridge case, heat-treated under the conditions of 50 ° C. and 20% RH for 4 hours, and further left to cool under the conditions of 23 ° C. and 55% RH for 1 hour. Then release the film from the core and pinch it with the clip, with the outer edge of the film roll up, and hang it. In this state, 1 more under the condition of 23 ° C and 55% RH.
Leave for hours. After this, the degree of curl curl at the lower end of the film is determined by the reciprocal of the radius of curvature. The unit is m ^-1 .

The thickness of the biaxially stretched polyester film is not particularly limited. It may be set so as to have a required strength according to the purpose of use. In particular, when the film is used for a roll-shaped photographic film for photographing represented by color negative and reversal, it is preferably 20 to 125 μm, and particularly preferably 40 to 90 μm. When it is used for medical or printing photographic film, it is 50-200μ.
m, particularly preferably 60 to 150 μm. If it is thinner than this range, the required strength may not be obtained,
If it is too thick, it loses its superiority to conventional photographic film supports.

In order to obtain a photographic light-sensitive material free from problems such as scratches and out-of-focus in the step of printing on photographic printing paper, it is preferable to impart curl in the width direction of the biaxially stretched polyester film. The effect is exhibited when the photographic photosensitive layer is provided on the convex side of the curl of the film and the film is wound with its surface facing inward.

The degree of curl imparted to the film for such a purpose varies depending on the thickness, elastic modulus, coefficient of hygroscopic expansion of the photographic photosensitive layer to be provided, and therefore cannot be determined unconditionally. It may be applied as far as possible so as to become flat within a range in which the photosensitive layer side is not a convex, usually, 23 ° C., a 5 m ^-1 50 m ^-1 under the conditions of RH 20%. The degree of curl is a value obtained as follows.

<Curling degree in the width direction> The width from the film is 35
mm, the test piece cut into a length of 2 mm, 23 ℃,
After conditioning the humidity for 1 day under the condition of 20% RH, the radius of curl of the curl in the width direction of the sample is determined in meters, and the reciprocal thereof represents the curl degree in the width direction. The unit is m ^-1 .

The method of imparting curl in the width direction to the film is not particularly limited. For example, a method of laminating polyesters having different copolymerization components or main constituents, or the same or different polyesters having different intrinsic viscosities are used. A method of laminating, a method of further changing the thickness of both outer layers with a three-layer structure, a method of changing the stretching conditions of the front and back and heat setting conditions to give a molecular orientation and a crystallinity distribution in the thickness direction of the film, and the like. To be In addition, a method of treating with a chemical solution using resorcin or the like can also be mentioned. Furthermore, combining these methods appropriately,
It is of course possible to impart curl using these methods in a layer structure of four or more layers.

The biaxially stretched polyester film of the present invention preferably has a haze of 3% or less. More preferably, it is 1% or less. When the haze is more than 3%, when the film is used as a support for a photographic light-sensitive material, an image printed on a photographic printing paper is blurred and unclear.
The haze is measured according to ASTM-D1003-52.

The Tg of the biaxially stretched polyester film of the present invention is preferably 60 ° C. or higher, more preferably 70 ° C. or higher. Tg is calculated as an average value of the temperature at which the baseline starts to be biased, which is measured by a differential scanning calorimeter, and the temperature at which the baseline newly returns. When Tg is not less than this value, there is no deformation of the film in the drying step of the development processor, and a photosensitive material with a small curl after development is obtained.

Next, a method for producing the polyester film will be described.

The method for obtaining an unstretched sheet and the method for uniaxially stretching in the machine direction can be carried out by conventionally known methods.
For example, the raw material polyester is molded into pellets, dried with hot air or vacuum dried, melt-extruded, extruded into a sheet from a T-die, brought into close contact with a cooling drum by an electrostatic application method or the like, and then cooled and solidified, An unstretched sheet is obtained. Then, the obtained unstretched sheet is heated in a range of glass transition temperature Tg of polyester to Tg + 100 ° C. through a plurality of roll groups and / or a heating device such as an infrared heater, and is subjected to single-stage or multi-stage longitudinal stretching. . The draw ratio is
It is usually required to be in the range of 2.5 times to 6 times so that subsequent transverse stretching is possible. When the sheet has a multi-layered structure, the stretching temperature is preferably set based on the highest Tg of the polyester Tg of each constituent layer.

At this time, when polyester is laminated,
A conventionally known method may be used. For example, a co-extrusion method using a plurality of extruders and a feed block type die or a multi-manifold type die, a single layer film constituting a laminate or other resin constituting a laminate on a laminate film is melt extruded from the extruder and cooled. Examples thereof include an extrusion laminating method of cooling and solidifying on a drum, and a dry laminating method of laminating a monolayer film or a laminated film constituting a laminate with an anchor agent or an adhesive as required.

Of these, the coextrusion method is preferable because it requires few manufacturing steps and has good adhesion between the layers.

Next, the longitudinally uniaxially stretched polyester film obtained as described above is transversely stretched within the temperature range of Tg to melting point (hereinafter Tm) -20 ° C., and then heat set. The transverse stretching ratio is usually 3 to 6 times, and the longitudinal and
The ratio of the transverse stretching ratio is appropriately adjusted so that the obtained biaxially stretched film has physical properties measured and has desirable properties.

In the case of the present invention, it is preferable that the elastic modulus in the width direction is higher than the elastic modulus in the longitudinal direction, and it may be appropriately changed depending on the purpose of use. At this time, it is preferable to laterally stretch while gradually raising the temperature difference in the range of 1 to 50 ° C. in the stretching regions divided into two or more because the distribution of the physical properties in the width direction can be reduced. Further, after the transverse stretching, the film is 0.01 to 5 in the range of the final transverse stretching temperature or lower and Tg-40 ° C or higher.
Holding for a minute is preferable because the distribution of physical properties in the width direction can be further reduced.

The heat setting is generally 0.5 to 30 at a temperature higher than the final transverse stretching temperature and within a temperature range of Tm-20 ° C. or lower.
Heat set for 0 seconds. At this time, it is preferable to heat-set while sequentially raising the temperature difference in the range of 1 to 100 ° C. in the two or more divided regions.

The heat-fixed film is usually cooled to Tg or less, cut at the clip holding portions at both ends of the film, and wound into a roll. At this time, it is preferable to perform a relaxation treatment in the width direction and / or the longitudinal direction by 0.1 to 10% within a temperature range from Tg to the final heat setting temperature. Further, for cooling, it is preferable to gradually cool from the final heat setting temperature to Tg at a cooling rate of 100 ° C. or less per second. The means for cooling and relaxing treatment is not particularly limited, and it can be carried out by a conventionally known means. However, it is particularly preferable to perform these treatments while sequentially cooling in a plurality of temperature regions from the viewpoint of improving the dimensional stability of the film. The cooling rate is a value obtained by (T ₁ −Tg) / t, where T ₁ is the final heat setting temperature and t is the time required for the film to reach Tg from the final heat setting temperature. More optimal conditions of these heat setting conditions, cooling, and relaxation treatment conditions differ depending on the polyester constituting the film, so by measuring the physical properties of the obtained biaxially stretched film and adjusting appropriately so as to have preferable properties. Just decide.

In the production of the above film, functional layers such as an antistatic layer, a slipping layer, an adhesive layer and a barrier layer may be coated before and / or after stretching. At this time, various surface treatments such as corona discharge treatment and chemical treatment can be applied as necessary. Further, for the purpose of improving the strength, it is also possible to carry out stretching which is used for known stretched films such as multi-stage longitudinal stretching, re-longitudinal stretching, re-longitudinal transverse stretching and transverse / longitudinal stretching. Of course, the clip gripping parts on both ends of the cut film are pulverized or, if necessary, granulated or depolymerized.
After performing a process such as repolymerization, it may be reused as a raw material for a film of the same type or as a raw material for a film of a different type.

Since the biaxially stretched polyester film obtained as described above still has the property of being easily curled, it is further heat-treated at a temperature of (Tg-30 ° C.) or higher and Tg or lower. There is a need. The higher the treatment temperature is, the shorter the curling curl curling effect can be obtained, but if the treatment temperature is too high, (wrinkle), (push), or (fold) of the film may easily occur. On the contrary, when the treatment temperature is low, a long treatment time is required, but when the treatment temperature is too low, a sufficient curling curl reducing effect cannot be obtained. The treatment time is not particularly limited, but the curling curl reducing effect is recognized from 0.1 hour or more, and the higher the effect is obtained as the time is longer, it may be appropriately set so as to obtain the desired effect. However, if it is too long, the productivity will be poor, so up to 1500 hours is usually practical.

Since such a heat treatment requires a relatively long time, an extremely long pass line is required for the treatment while being conveyed. Therefore, the heat treatment is usually performed in a roll form. In this case, both ends of the film are processed. It is preferable to prevent the films from adhering to each other by, for example, embossing the central part. For this purpose, embossing is usually 5 to
It is preferable to process so as to form unevenness of 100 μm.
It is preferable to emboss at intervals of 50 cm to 2 m in the width direction of the film.

The core to be used in the heat treatment and the core to be wound up are not particularly limited, but it is preferable that the material and the structure have strength not to bend even when the film is wound and withstand the heat treatment temperature. The smoother the surface of the core, the better, and the surface roughness (R _max ) is preferably 2.0 μm or less. Examples of these include a resin roll, a fiber-reinforced resin roll, a metal roll, and a ceramic coating roll. If the core diameter is too small, wrinkles and the like are likely to occur in the winding core portion, so the core diameter is preferably large if there is no restriction on equipment, and is usually 75 mm or more, and further preferably 200 mm or more. The roll diameter of the wound film roll is
If it is too large, uniform treatment becomes difficult, so it is preferably small to a certain extent, usually 1000 mm or less, more preferably 850 mm or less. The width of the film roll is not particularly limited, but a wider one is preferable from the viewpoint of productivity,
It is generally 150 mm or more and 3500 mm or less.

In the present invention, the end portion in the coating width direction (hereinafter, simply the end portion) perpendicular to the transport direction of the film at the time of applying the photographic constituent layer before the photographic constituent layer is applied.
Only the Tg of the polyester film or more, (Tg
It is characterized in that it is heat-treated at + 130 ° C or lower. Here, the end portion indicates a portion which is heat-treated at Tg or higher and (Tg + 130 ° C.) or lower.

This treatment may be carried out at any stage up to the coating of the photographic constituent layers, but it is needless to say that it is carried out just before the coating of the most susceptible layer among the layers. preferable. In general, a subbing layer or a back layer having a smaller layer thickness is more likely to be affected than a photographic emulsion layer having a relatively thick layer, and therefore, it is preferable to perform it before coating the back layer. If the heat treatment temperature is too low, the unevenness of the coating thickness will not be improved. On the contrary, if it is too high, the film will be softened and the flatness will be deteriorated.

The heat treatment time is not particularly limited and can be appropriately set so as to obtain a desired effect. The higher the treatment temperature is, the shorter the effect is obtained, and the lower the treatment temperature is, the longer the treatment is required. Therefore, the necessary temperature and time conditions may be determined in consideration of the size of equipment.

Usually, the improvement effect is recognized from 3 seconds or more after the film reaches a predetermined temperature, and the effect is almost saturated at 100 minutes or more. Therefore, the preferable range is from 3 seconds to 100.
Within minutes.

The heating method is not particularly limited, and examples thereof include a method of heating only the end portion of the film in a non-contact manner using an infrared heater or an electric heater, or a method of heating by contacting a heating roll or the like. To be

The heating means described above may be provided immediately before the photographic constituent layers are applied to the film. In this case, the film may be once cooled to room temperature and then applied, or may be applied while the temperature of the edge of the film is higher than the temperature of the central part. By doing so, even if the end portion is thickly applied, the drying speed is increased, so that it is possible to prevent the process from being soiled due to insufficient drying.
Further, since the end portion of the film is Tg or more, if excessive tension is applied to this portion, the film may be stretched and the flatness may be deteriorated. In this case, the heat treatment can be prevented by carrying out the film while it is being carried by a device capable of controlling the carrying tension.

Since the film in the heated portion once becomes Tg or higher, the curling habit reducing effect disappears. Therefore,
The heat treatment range is preferably as small as possible within the range in which the effect is obtained. If the heating range is within 50 mm from the tip of the film, the loss will be too great and the improvement will be meaningless. The effect of the present invention begins to be recognized by heat-treating the area within 5 mm from the tip of the film. A higher effect can be obtained by heat-treating the area up to 10 mm inside. Therefore, it is preferably in the range of 5 to 50 mm from the tip of the film, and more preferably 10 to 10 mm from the tip of the film.
It is to heat-treat the area up to 50 mm inside.

By heat-treating only the edges of the film, the adhesion of the film to the roll is improved, and as a result, the gap between the film and the coater can be kept uniform in the coating width direction, and the coating thickness distribution Is significantly improved.

The Tg and Tm in the present invention are measured according to the following method.

10 mg of the film or pellet is melted at 300 ° C. in a nitrogen stream of 300 cm ^{3 /} min and immediately cooled in liquid nitrogen. The quenched sample is set in a differential scanning calorimeter (DSC8230, manufactured by Rigaku Denki Co., Ltd.) and heated at a heating rate of 10 ° C./min in a nitrogen stream of 100 cm ^{3 /} min.

Tg is the average value of the temperature at which the baseline begins to become eccentric and the temperature at which the baseline returns anew, and Tm is the peak temperature of the endothermic peak. still,
The measurement start temperature is a temperature lower than the measured Tg by 50 ° C. or more.

In the present invention, a photographic support can be obtained by coating at least one undercoat layer on the surface of the film. The material that can be used for the undercoat layer is not particularly limited, and examples thereof include a copolymer of vinyl chloride, vinylidene chloride, butadiene, methacrylic acid, acrylic acid, itaconic acid, maleic anhydride as a starting material, and polyethyleneimine. , Polyester, polystyrene, polyurethane, epoxy resin, grafted gelatin, nitrocellulose and the like, and mixtures thereof. In these subbing layers, surfactants, antistatic agents, antihalation agents, crossover cut agents, coloring dyes, pigments, thickeners, coating aids, antifoggants, antioxidants, ultraviolet absorbers, ultraviolet rays, etc. One kind or two or more kinds of various additives such as a stabilizer, an etching treatment agent, a magnetic powder and a matting agent may be contained.

The method of applying the undercoat layer is not particularly limited, and various conventionally known methods can be used. For example, a solution or dispersion prepared by dissolving the above materials in a suitable solvent is applied to the film surface using an air knife coater, a dip coater, a curtain coater, a wire bar coater, a gravure coater, an extrusion coater, etc., and dried. There is a method.
At this time, if necessary, a method of surface activation treatment such as corona discharge treatment, ultraviolet treatment, glow discharge treatment, plasma treatment, flame treatment, etc. and etching such as resorcin treatment, phenol treatment, alkali treatment, amine treatment, trichloroacetic acid treatment, etc. You may use the method of processing. Of course, these processes may be combined. Of these, corona discharge treatment is preferably used. From the viewpoint of working environment, the coating liquid is preferably an aqueous dispersion or an aqueous solution.

The subbing layer may be composed of one layer or two or more layers, and further comprises an antistatic layer, a slipping layer, a barrier layer, an antihalation layer, a crossover cut layer,
An ultraviolet absorbing layer, a magnetic recording layer, etc. may be included.

The film coated with the undercoat layer as described above is cooled to room temperature, wound up, and stored until it is sent to the next step. At this time, the water content of the film was set to 0.
It is preferable to adjust the content to 2% or less, because the curl due to storage can be prevented.

Next, a method of forming a photographic light-sensitive material will be described.

The photographic light-sensitive material has a photographic constituent layer provided on at least one side of a photographic support, and the photographic constituent layer can be formed by coating a silver halide emulsion. The photographic constituent layers can be provided on one side or both sides of the photographic support. The photographic constituent layers may be provided in one layer or two or more layers on each surface. The silver halide emulsion layer can be coated directly on the photographic support or through another layer, for example, a hydrophilic colloid layer containing no silver halide emulsion. Further, the silver halide emulsion layer may be separately coated on each of the silver halide emulsion layers having different sensitivities, for example, high sensitivity and low sensitivity. In this case, an intermediate layer may be provided between each silver halide emulsion layer. Further, a hydrophilic colloid layer, a protective layer, an antihalation layer, a backing layer, a masking layer, etc. may be formed on the silver halide emulsion layer or in an intermediate layer, or at any place between the silver halide emulsion layer and the photographic support. A non-photosensitive layer may be provided.

The silver halide emulsion used is, for example, Research Disclosure (hereinafter referred to as RD) N.
o. 17643, 22-23 (December 1979), "1. Emulsion preparation and typr.
s) ”, and RD No. 18716, pp. 648," The Physics and Chemistry of Photography "by Graphide, published by Paul Montell (P.Gl.
kides, Chemie et Phyzique Photographique, Paul Monte
, 1967), "Photoemulsion Chemistry" by Duffin, published by Focal Press (GFDaffin, Photographic Emulsion Chemist
ry Focal Press 1966), "Manufacturing and coating of photographic emulsions" by Zelikmann et al., published by Focal Press (VLZelikman e
tal, Making and coating Photographic Emulsion Focal
Press 1964) and the like.

Silver halide emulsions are described in US Pat. No. 3,574,628
The monodisperse emulsions described in U.S. Pat. No. 3,665,394 and British Patent 1,413,748 are also preferable. The silver halide emulsion can be subjected to physical ripening, chemical ripening and spectral sensitization.

The additives used in such a process are RD
No. 17643, 18716 and 308119. Table 1 shows the location of the description.

[0077]

[Table 1]

When the photographic light-sensitive material is color, the photographic additives that can be used are described in the above RD. Table 2 shows the relevant locations.

[0079]

[Table 2]

Further, various couplers can be used, and specific examples thereof are RD No. described above. 17643 and 3
08119. Table 3 shows the location of the description.

[0081]

[Table 3]

Further, these additives are RDNo. 3081
It can be added to the photographic light-sensitive layer by a dispersion method or the like as described in No. 19, page 1007, XIV.

RD No. 308119 VII-K
An auxiliary layer such as a filter layer or an intermediate layer described on the page may be provided, and various layer structures such as a forward layer, an inverse layer and a unit structure may be adopted.

In the development processing, for example, T. H. James, The Theory of The Photographic Proce
ss Forth Edition) pp. 291-334 and Journal of American Chemical Society (Jour
nal of The American Chemical Society) 73, 3,100 (1951), known developers can be used. Also, the above-mentioned RD
No. 17643, pp. 28-29, ibid. 187166.
Development can be carried out by a usual method described on page 15 and 308119 XIX.

[0085]

The present invention will be described in detail below with reference to examples, but the embodiments of the present invention are not limited thereto.

In the following examples, the intrinsic viscosity, the film haze, the elastic modulus and the breaking strength are obtained as follows.

(1) Intrinsic viscosity (IV) A film or pellet was treated with phenol, 1, 1, 2,
2-Tetrachloroethane mixed solvent (weight ratio 60/4
0 g) to have a concentration of 0.2 g / dl, 0.6 g / dl,
A 1.0 g / dl solution is prepared, and the specific viscosity (ηsp) at each concentration (C) is determined by an Ubbelohde viscometer at 20 ° C. Then, ηsp / C is plotted against C, and the obtained straight line is extrapolated to zero concentration. Ask for. The unit is indicated by dl / g.

(2) Film haze Measured according to ASTM-D1003-52.

(3) Elastic Modulus and Breaking Strength The film was cut into a size of 10 mm in width and 200 mm in length and conditioned at 23 ° C. and 55% RH for 12 hours, and then manufactured by Orientec Co., Ltd. Tensilon (RTA-1
No. 00) was used and the distance between the chucks was set to 100 mm, and a tensile test was performed at a tensile speed of 100 mm / min to determine the elastic modulus and the breaking strength.

Example 1 A polyester film was prepared as follows.

(Polyester A) 0.1 parts by weight of calcium acetate hydrate as an ester exchange catalyst was added to 100 parts by weight of dimethyl 2,6-naphthalenedicarboxylate and 60 parts by weight of ethylene glycol, and the ester exchange reaction was carried out according to a conventional method. went. To the obtained product, 0.05 part by weight of antimony trioxide and 0.03 part by weight of trimethyl phosphate were added. Then, gradually raise the temperature and reduce the pressure,
Polymerization was carried out at 0 ° C. and 0.5 mmHg, and an intrinsic viscosity IV =
0.60 of polyethylene-2,6-naphthalate was obtained.

(Polyester B) Dyes Macrolex Green G and Macrolex Red 5B manufactured by Bayer Co. were added to polyester A at a ratio of 1: 1 and an extruder was used to prepare master pellets having a dye concentration of 2000 ppm.

A film was obtained in the following manner using each of the polyesters obtained as described above.

Polyester A and polyester B were blended in a tumbler type mixer in a weight ratio of 9: 1. Then, after vacuum drying at 150 ° C. for 8 hours, 30
Melt extrusion was carried out in layers from a T-die at 0 ° C., and it was brought into close contact with a cooling drum at 50 ° C. while electrostatically applied, and cooled and solidified to obtain an unstretched sheet. This unstretched sheet was stretched 3.3 times in the longitudinal direction at 135 ° C. using a roll type longitudinal stretching machine.

The obtained uniaxially stretched film was stretched in a first stretching zone at 145 ° C. by 50% of the total transverse stretching ratio using a tenter type transverse stretching machine, and then at a second stretching zone at 155 ° C. in a total transverse stretching ratio of 3. It was stretched so as to be 3 times. Then 100
Heat treatment was performed at 2 ° C. for 2 seconds, heat setting was performed at 200 ° C. for 5 seconds in the first heat setting zone, and heat setting was performed at 240 ° C. in the second heat setting zone for 15 seconds. Then, the film was cooled to room temperature over 60 seconds while being relaxed in the transverse direction by 5%, and the film was released from the clip and wound to obtain a biaxially stretched film having a thickness of 90 μm. The film obtained as described above was slit to a width of 1 m, and while applying embossing rings controlled at 270 ° C to both ends of the film, a height of 15 μm and a width of 10 mm were embossed, then a diameter of 200 mm and a surface roughness were obtained. (R
_max ) 0.8μm SUS core, initial tension 25k
It was wound up for 1000 m while changing the tension so that the gf and the final tension were 20 kgf.

Next, while the film was wound on the core, heat treatment was carried out at 110 ° C. for 24 hours to reduce the winding habit. The heat treatment was performed by raising the temperature over 24 hours, treating it at a prescribed temperature for a prescribed time, and then cooling it to room temperature over a further 24 hours.

The characteristic values of the obtained film were as follows.

Tg 120 ° C. Tm 272 ° C. IV Intrinsic viscosity 0.58 dl / g Haze 0.6% Elastic modulus Vertical direction 650 kg / mm ² Horizontal direction 700 kg / mm ² Breaking strength Vertical direction 22 kg / mm ² Horizontal direction 24 kg / mm ^{2 Then} , in the process before the undercoat layer coating process, the conveying tension was 20 k.
While controlling to g / m, only the edge of the film is controlled by the infrared heater installed at the edge of the film.
Heat treatment was performed while changing as shown in FIG.

The infrared heater is equipped with a reflector, and a rectangular window is opened on the irradiation side, and the irradiation range of this window can be changed by a shutter. The gap with the film was 20 mm.

The heat treatment time was changed by setting 10 sets of such infrared heaters in the longitudinal direction and changing the conveying speed and the number of infrared heaters used. The heat treatment time was represented by the time taken for the film to pass through the infrared heater section.

The heat treatment temperature is represented by the film temperature at the exit of the infrared heater section.

Thereafter, the film is allowed to pass through a plurality of guide rolls and naturally cooled to room temperature, and then the film is guided to a coating step,
The undercoat layer was applied as follows.

8 W / on the side of the film which is the photographic emulsion side
(M ² · min) corona discharge treatment, 2 on it
Using a roll-fit coating pan and an air knife in an atmosphere of 5 ° C. and 50% RH, the following coating liquid A-
1 was prepared, applied, and dried at a drying temperature of 115 ° C. for 1 minute to form a layer having a thickness of 0.8 μm after drying.

<Coating Liquid A-1> Copolymer latex liquid of butyl acrylate 30 wt% t-butyl acrylate 20 wt% styrene 25 wt% 2-hydroxyethyl acrylate 25 wt% (solid content 30%) 270 g Compound (UL -1) 0.6 g Hexamethylene-1,6-bis (ethylene urea) 0.8 g Water to make 1000 ml.

Further, the following coating liquid A-2 was applied to the coating surface A-1.
Was prepared, applied and dried to form a layer having a thickness of 0.1 μm.

<Coating Liquid A-2> Gelatin 10 g Compound (UL-1) 0.2 g Compound (UL-2) 0.2 g Compound (UL-3) 0.1 g Silica particles (average particle diameter: 3 μm) Make up to 1000 ml with 1 g water.

Next, the following coating solution B-1 was prepared and applied to the back layer side of the film and dried at a drying temperature of 115 ° C. for 1 minute to form a layer having a thickness of 0.8 μm after drying.

<Coating Liquid B-1> Butyl acrylate 40% by weight Styrene 20% by weight Glycidyl acrylate 40% by weight Copolymer latex liquid (solid content 30%) 270 g Compound (UL-1) 0.6 g Hexamethylene-1 , 6-Bis (ethylene urea) 0.8 g Make up to 1000 ml with water.

Then, the following coating solution B-2 was prepared and coated on the B-1 coated surface in the same manner, and dried at a drying temperature of 115 ° C. for 1 minute to form a layer having a thickness of 0.8 μm after drying. did.

<Coating Liquid B-2> Compound (UL-4) 60 g Latex liquid containing compound (UL-5) as a component (solid content 20%) 80 g Ammonium sulfate 0.5 g Compound (UL-6) 12 g Polyethylene glycol ( Weight average molecular weight 600) 6 g Make up to 1000 ml with water.

Further, a back layer was applied as follows.

B-2: The following coating solution B-3 was prepared and coated on the coated surface in an atmosphere of 30 ° C. and 50% RH using a wire bar, dried at a drying temperature of 90 ° C. for 1 minute, and dried. A later layer having a thickness of 0.1 μm was formed.

<Coating Liquid B-3> Diacetylcellulose 10 g Acetone 400 ml Methanol 600 ml Further, the following coating liquid B-4 was prepared on the B-3 coated surface using a wire bar in an atmosphere of 30 ° C. and 50% RH. 10 ml / m ^{2 was} applied, and the back layer was finished by drying at a drying temperature of 90 ° C. for 1 minute.

<Coating Liquid B-4> Carnauba wax 1 g Toluene 700 ml Methyl ethyl ketone 300 ml

[0115]

Embedded image

[0116]

Embedded image

<Coating of Photosensitive Layer> A of the above film
The surface of the layer was subjected to a corona discharge treatment of 25 W / (m ² / min) and then coated with a photographic emulsion for Konica LV400 to prepare a color photographic film.

<Evaluation> (Non-uniform coating thickness) The non-uniform coating thickness of the color photographic film obtained as described above was evaluated. For the evaluation, after measuring the entire thickness of the color photographic film, the thickness after the back layer side was wiped off with acetone was measured, and the difference was defined as the coating thickness.

The distribution of the coating thickness in the width direction was measured, and the absolute value of the difference between the coating thickness of 50 mm inside from the edge of the film and the coating thickness of the central portion was divided by the coating thickness of the central portion to obtain a thickness unevenness rate (percentage). evaluated. The results were ranked according to the following criteria. The practicality in this ranking is determined based on the tolerance of the quality of the photographic light-sensitive material, and it is necessary that the rank is ◯ or higher.

Rank Thickness unevenness rate ◎ Less than 10% ○ 10% or more and less than 20% × 20% or more (press-price transportability) The obtained color photographic film was cut into a width of 35 mm and a length of 1200 mm, and both edges thereof were cut. Perforation processing was performed as described in JIS7519-1982. The press price transportability of the cut color photographic film was evaluated. That is, the color photographic film was prepared at 23 ° C. for 5
After conditioning the humidity for 1 day under the condition of 5% RH, the photographic photosensitive layer side is placed inside and wound around a core having a diameter of 7 mm and fixed so as not to return. Next, this film is put in a polyethylene cartridge case, heat-treated under the conditions of 50 ° C. and 20% RH for 4 hours, and further left to cool under the conditions of 23 ° C. and 55% RH for 1 hour. After that, the film was released from the winding core, and was inserted into a Noritsu Press Splicer PS-35-1 (manufactured by Noritsu Koki Co., Ltd.) so that the winding core side became the leading end. The following criteria were used to rank 10 through each level according to the number of occurrences of defective conveyance.

Rank Number of occurrences of poor conveyance ⊚ 0 ∘ 1 x 2 to 10 These results are shown in Table 4.

[0122]

[Table 4]

* Distance from the tip of the film As can be seen from Table 4, according to the present invention, the suitability for press-plying is excellent and the unevenness of the coating thickness is improved. On the other hand, in level 9, the edge of the film was heat-treated at a predetermined heating temperature or higher, so that the edge of the film was loosened, and conversely, the film was heat-treated at a predetermined heating temperature or lower. It can be seen that both the level 10 and the level 11 in which the end portion of the film is not heat-treated are poor in practicability and unevenness in coating thickness and are not suitable for practical use.

[0124]

According to the present invention, it is possible to provide a photographic support which is excellent in transparency, strength and press-price transportability and has improved coating thickness unevenness.

Claims (4)

[Claims] 1. A photographic support comprising a biaxially stretched polyester film having a glass transition temperature of Tg, which is (Tg-30 ° C.) or more and Tg or less after formation of the film to prevent curl. After the heat treatment in the range, before the photographic constituent layer is coated on the film, the end in the coating width direction perpendicular to the transport direction at the coating of the film is Tg or more and (Tg + 130 ° C.) or less. A photographic support characterized by being heat-treated in the range of. 2. The biaxially stretched polyester film,
The photographic support according to claim 1, which contains 70% by weight or more of ethylene-2,6-naphthalenedicarboxylate unit. 3. A method for producing a photographic support comprising a biaxially stretched polyester film having a glass transition temperature of Tg, wherein the film is formed at a temperature of (Tg-30 ° C.) or higher to prevent curl after formation. , Tg or more and Tg or more (Tg + 130) at the end in the coating width direction perpendicular to the transport direction at the time of coating of the film before the film is coated with the photographic constituent layer after heat treatment. C.) A method for producing a photographic support, which comprises performing heat treatment in the following range. 4. The biaxially stretched polyester film,
The method for producing a photographic support according to claim 3, wherein the ethylene-2,6-naphthalene dicarboxylate unit is contained in an amount of 70% by weight or more.