JPH04124648A - Production of anti-static silver halide film photosensitive material - Google Patents

Abstract

PURPOSE:To obtain the silver halide photographic sensitive material having a good antistatic property by using a copolymer of specific N-methylol (meth) acrylamide and styrene sulfonic acid as a conductive polymer and specifying the humidity at the time of drying. CONSTITUTION:The conductive polymer is constituted of the copolymer of the N-methylol (meth)acrylamide and the styrene sulfonic acid in the process for production of the silver halide film photosensitive material having the conductive polymer layer between the back coat layer contg. gelatin and a film base. The ratio of the N-methylol (meth)acrylamide in the copolymer is specified to >=10wt.% and <=60wt.%. This copolymer is applied on the film base and the film base is taken up in the form of a mill roll after the end of drying. The relative humidity of this time is preferably 40 to 60%. The density of the film increases too much if the relative humidity is <=40%. The increased resistance and the poor adhesion to the back coat layer are then resulted and such is undesirable. Blocking is liable to arise and the adhesion with the back coat layer is poor if the relative humidity is >=60%.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention relates to silver halide photographic materials, and more particularly to a method for producing an antistatic backing layer.

(B) Prior art and its problems Silver halide photographic materials use films, paper, etc. as a base, but these have low conductivity and have caused various problems.

One of these problems is that when applying a coating solution containing silver halide to film, paper, etc., it is coated at high speed with a coater, but while it is being rubbed by a roller, it is charged and charged. The problem is that silver halide is coupled during discharge (static fog). If the backing layer has high conductivity and antistatic properties, the backing layer is usually applied before the silver halide emulsion is applied, so that the backing layer passes through the base and covers the side to be coated with the opposite emulsion. It also improves antistatic properties and prevents static fog.

Second, when users use photosensitive materials, if they are charged, dirt and dust may adhere to the photosensitive materials and form undesirable images such as pinholes during exposure and photographic processing. However, there is a problem in that the photosensitive materials stick together, resulting in poor workability. Furthermore, there is also the problem that these photosensitive materials discharge when passed through human hands.

What is important in these problems is that charging characteristics must be good both before and after processing such as development, fixing, and washing with water.

Patent Publication No. 56-92535, opening/closing 61-1745
According to No. 42, an antistatic layer may be provided between the backing layer and the base, and an aziridine hardener may be used to increase the antistatic properties through this layer and to improve the adhesion between this layer and the backing layer. Are listed. However, aziridine hardeners cause skin fogging, which is undesirable from a safety and hygiene perspective.Furthermore, because an antistatic layer is provided between the aziridine hardener and the base, the adhesion of the backing layer is insufficient and drying properties are poor. was.

(C) Purpose of the Invention The purpose of the present invention is to provide a method for manufacturing a backing layer with good antistatic properties, and furthermore, to provide a method for manufacturing a backing layer with good adhesion and excellent antiblocking properties. The purpose is to provide a method.

(D) Structure of the Invention The present invention provides a method for producing a silver halide film photosensitive material having a conductive polymer layer between a film base and a backing layer containing gelatin, wherein the conductive polymer is N-methylol (meth). Consisting of a copolymer of acrylamide and styrene sulfonic acid, the copolymerization ratio of N-methylol (meth)acrylamide is 10% by weight or more and 60% by weight or less, and the drying humidity at the time of coating the polymer layer is 40°C or higher. After drying, the film is rolled up in an atmosphere with a relative humidity of 40 to 60%, and a backing layer containing gelatin is further applied on the conductive polymer layer under arbitrary conditions.

The conductive polymer used in the present invention is N-methylol (
It is a copolymer of meth)acrylamide and styrene sulfonic acid, and crosslinks when heated. The ratio of N-methylol (meth)acrylamide in the copolymer is 10% by weight or more and 60% by weight or less. If the ratio is less than 10% by weight, sufficient crosslinking will not occur upon heating and the resin will not be able to withstand alkaline or acidic photographic processing. Furthermore, if the ratio exceeds 60% by weight, the proportion of styrene sulfonic acid or its alkali metal salt involved in the antistatic layer is relatively reduced, and sufficient antistatic properties cannot be obtained.

The copolymer is produced by dissolving a mixture of P-styrene sulfonic acid or its alkali metal salt and N~methylol(meth)acrylamide in a mixed solvent of alcohol/water, and dissolving the monomer in the medium. However, as the polymerization progresses, the polymer is formed, becomes insoluble in the medium, and precipitates. Particularly preferred are water/alcohol mixed solvent systems containing alcohol in a concentration of at least 40% by weight. When performing such polymerization, by making a soluble resin exist in the medium in advance,
The precipitated polymer is obtained in the form of fine particles.

That is, in the presence of a polymer that acts as a dispersion stabilizer, polymerization is carried out under conditions such that the monomer state is soluble in the medium, but the polymer becomes insoluble.

Furthermore, in the present invention, various monomers other than styrene sulfonic acid or its alkali metal salt and N-methylol (meth)acrylamide can be copolymerized as the third component, but among them, monomers having acidic groups are particularly copolymerized. By doing so, the thermosetting properties of the film can be further promoted.

Such monomers include (meth)acrylic acid,
Preference is given to copolymerization of acidic monomers such as 2-acrylamido-2-methylpropanesulfonic acid or maleic acid. The copolymerization ratio of such acidic monomers is preferably in the range of about 0.5% by weight to 10% by weight.

The thermosetting antistatic polymer of the present invention is synthesized with the above composition, and basically forms a water-resistant antistatic film with sufficient performance. As monomers other than those mentioned above, monomers such as styrene, derivatives thereof, and (meth)acrylic acid esters may be copolymerized.

As counter ions for styrene sulfonic acid, alkali metal ions such as sodium ions and potassium ions are preferred. A synthesis example is shown below.

Synthesis Example 1 Polyvinylpyrrolidone '7 was placed in a 500 m 14 flask equipped with a stirrer, thermometer, nitrogen inlet tube, and reflux condenser.
g, 70 g of sodium p-styrenesulfonate, and 30 g of N-methylolacrylamide, and ethanol 2
00g and 100g of distilled water were added and dissolved at 70°C. When polymerization was initiated by adding 1,0 g of AIBN at 75° C. under a nitrogen atmosphere, a stable white emulsion was produced.

Three hours after the start of polymerization, ethanol was distilled off under reduced pressure to obtain a homogeneous low-viscosity polymer aqueous solution.

Synthesis Example 2 Similarly to Synthesis Example 1, 7 g of polyvinylpyrrolidone, p-
70 g of sodium styrene sulfonate, 30 g of 5N methylolacrylamide and 5 g of 2-acrylamido-2-methylpropanesulfonic acid were dissolved in a mixed solvent containing 150 g of ethanol and 150 g of distilled water at 70°C, and ABIN'1. Polymerization was initiated by adding Og. Immediately after the start of polymerization, only fine white polymer particles were precipitated and the system became a milky white emulsion.

About 1 hour after the start of polymerization, 50 g of ethanol was added, and the mixture was further heated and stirred for about 2 hours.

Thereafter, ethanol was distilled off under reduced pressure to obtain a homogeneous aqueous solution.

Synthesis example 3 7 g of polyvinylpyrrolidone as in Synthesis Example 1.

70 g of sodium p-styrene sulfonate, 25 g of N-methylolacrylamide, and 5 g of methacrylic acid were dissolved in 200 g s of ethanol and 100 g of distilled water, and polymerization was initiated by adding AIBNl and Og at 75°C.

The product was a stable emulsion with a particle size of less than 1 micron.

Synthesis Example 4 Same as Synthesis Example 1, polyvinyl alcohol (Kuraray PV
A203, partially saponified polyvinyl acetate) Log, p-
Sodium styrene sulfonate 70g 5N-methylolacrylamide 30g and 2-acrylamide-2-
5 g of methylpropanesulfonic acid was dissolved in a mixed solvent of 150 g of ethanol and 150 g of distilled water.

Polymerization was started by adding AIBNl and Og at 75° C. under a nitrogen atmosphere. In order to stabilize the resulting emulsion, 50 g of ethanol was further added dropwise over 3 hours.

Thereafter, ethanol was distilled off under reduced pressure to obtain a homogeneous aqueous solution.

The drying temperature during coating of the copolymer of N-methylol (meth)acrylamide and styrene sulfonic acid of the present invention is 40°C.
or higher, preferably 50°C or higher. If the drying temperature is low, not only will it be impossible to form a film that can withstand photographic processing, but the resistance value will become particularly high after processing, which is undesirable. Roll it up into a mill roll without drying it thoroughly and heat it at a high temperature (40℃).
℃ or higher) for several weeks, but this method tends to cause blocking and requires several weeks of mill roll heating, which is not economical.

When the copolymer of N-methylol (meth)acrylamide and styrene sulfonic acid of the present invention is applied, it is wound up into a mill roll after drying, and the relative humidity at this time is very important.

Relative humidity is preferably 40-60%, especially 45-55%.
% is preferred. If it is less than 40%, the resistance value is high and the adhesion with the backing layer is poor, probably because the density of the film is too high, which is not preferable. If the relative humidity is over 60%,
Blocking tends to occur and adhesion with the backing layer deteriorates.

The coating amount of the conductive polymer of the present invention is preferably 0.1 g to 5.0 g as solid content per coat. Preferably 0.5g to 2
．． It is 0g. If the coating amount is less than 0.1 g, the antistatic properties will be poor and it will not be practical.

If the coating amount is 5.0 g or more, the adhesion with the backing layer will deteriorate, which is not preferable.

The conductive polymer layer used in the present invention is located between the gelatin-containing backing layer and the film base,
Other positions are not preferred.

For example, if an antistatic layer is provided on the opposite side of the base via a backing layer, - since the backing layer contains a filter dye, dye loss will be a problem (which is undesirable). When an antistatic layer is provided between the film bases, it is generally disadvantageous that the emulsion layer requires stronger adhesion than the back side when a stripping film is attached or the like.

Furthermore, providing an antistatic polymer layer between the emulsion layer and the protective layer or outside the protective layer from the film base is disadvantageous in terms of development progress and fixing speed.

Therefore, it is most logical to place the antistatic polymer layer between the film base and the gelatin-containing backing layer.

It is also conceivable that the backing layer does not contain gelatin and consists of only a water-soluble or water-insoluble polymer layer or only a conductive polymer layer, but in this case, the emulsion layer and protective layer are mainly composed of gelatin, so curling may occur. Strong and impractical.

The amount of gelatin in the backing layer is lrT! Hit 0. 5-8g
1, preferably 1 to 5 g. The backing layer further contains the conductive polymers described above, other conductive polymers, water-soluble polymers, hardeners, matting agents, antihalation dyes,
A surfactant or the like may be included if necessary.

The film base used in the present invention is mainly a polyethylene terephthalate film, but other polyester bases are also included.

When coating the polymer of the present invention, coating properties are improved by using a surfactant. Basically, anything that lowers the surface tension may be used, but the following general formula [I], (I
The surfactant I) is particularly excellent.

General formula CI) R-0-(-CH2CH20+-T-8O3M general formula) In the formula, n is a natural number from 1 to 20 R1 is a C6 to CI5 optionally substituted alkyl group or aryl group, R2 is a C3 to C5 Alkyl group that may be substituted.

Exemplary compounds are shown below, but of course the invention is not limited to these.

-a HIs e t -0-eCf(2 CH2 O+-r-803 a -b 27CI3 0(CH2 CH2 0)TS03 a -S(J3 Na ■ f Exemplary compound I-c 10CH3 P\ 1-d C++ H, , -0 io CH2 H2 0÷ko] - -e CI5H31-0+CH2 H2 0+-TV- If C5 18CI -o-+CH2 H2 0 sho 1- (E) Examples Example 1 30 weight in 500 ml of distilled water 500 ml of a 10% solution of sodium polystyrene sulfonate with % N methylol acrylamide was added and i□n+1 of a 10% solution of surfactant of exemplified compound I-a was added.

Maximum temperature of coater drying zone from 20 to 70℃1
It was coated on a 100μ underlined polyethylene terephthalate film at 0°C increments. Coating amount is 20ml
/m and the coating speed was 20 m/mn. The atmosphere from the end of drying to the part of the wine ring is 25℃ and relative humidity is 50℃.
%.

It was rolled up with wine goo and placed in a moisture-proof bag and left at room temperature for 3 days.

A gelatin solution was then applied as a backcoat over the conductive polymer layer. Gelatin solution is inert gelatin 50
g was dissolved in 950 ml of distilled water, and 20 ml of a 10% solution of Exemplified Compound Ia as a surfactant was added thereto.

10% 2,4 dichloro-6-hydroxy- as hardener
25 ml of No. 34 riazine was added, and the coating amount was 50 ml/-. The drying temperature at this time is 45°C.

These samples were heated at 50° C. for one day, and the heated samples were processed using a GR-14 automatic processor manufactured by Konishirokusha. Developed using MRACD-101 manufactured by Mitsubishi Paper Mills Co., Ltd. at 35℃20
The fixing time was CF-901 at 35°C for 20 seconds.

Antistatic ability is measured at 25℃50%R for samples before and after treatment.
The surface resistance was measured after being left in an atmosphere of H (relative humidity) for 2 hours using a Hiresta surface resistance meter model HT- manufactured by Mitsubishi Yuka Co., Ltd.
Measured at 210. A rough guide for surface resistance is 1012Ω.
A value of 10 11 Ω or less is considered a good level.

Adhesion was evaluated by making square scratches on the surface of the sample with a knife at 5 mm intervals, immersing the sample in water at 30° C. for 30 seconds, and then rubbing the surface with a tissue. ○
The mark indicates that the film will not come off at all, the mark △ means that it will come off slightly, and the mark X means that it will come off considerably.

These results are shown in Table 1.

(The following is a blank space) As shown in Table 1, when the drying temperature is 30° C. or lower, the adhesion and the resistance value after treatment are insufficient.

It seems that drying for a long time at 20 to 30°C would be sufficient, but even if the coating speed was set to 10 m/min, this data hardly changed, and it seems that the water retention of the polymer is involved.

Example 2 Next, the maximum temperature of the drying zone of the coater was set to 50°C, and the atmosphere from the drying end part to the wine section was set to 25°C.
The relative humidity was varied from 30 to 70% in 10% steps. Other conditions are exactly the same as in Example 1.

These results are shown in Table 2.

(Left space below) As shown in Table 2, those with a relative humidity of 30% have poor adhesion and high resistance. 70% of them have some blocking and poor adhesion. Therefore, when using a polymer of N-methylol (meth)acrylamide and styrene sulfonic acid as an antistatic layer, it is important to keep the drying temperature at 40°C or higher and the winding humidity at 40 to 60%. Recognize.

Claims (1)

[Claims] A method for producing a silver halide film photosensitive material having a conductive polymer layer between a gelatin-containing backing layer and a film base, wherein the conductive polymer is made of a copolymer of N-methylol (meth)acrylamide and styrene sulfonic acid. The copolymerization ratio of N-methylol (meth)acrylamide is 10% by weight or more and 60% by weight or less, and the drying humidity at the time of coating the polymer layer is 40°C or more, and the relative humidity after drying is 40 to 60%. Winding in an atmosphere of %,
A method for producing a silver halide film photosensitive material, further comprising applying a back coating containing gelatin on the conductive polymer layer.