JPH04124652A - Antistatic silver halide film photosensitive material - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (A) Industrial Application Field The present invention relates to silver halide photographic materials, and more particularly to antistatic backing layers.

(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 10ogenide to film, paper, etc., it is applied at high speed with a coater, but it becomes charged while being rubbed by a roller. This is a problem in that silver halide is fogged when discharged (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 Publications No. 5-6-92535, No. 61-174
According to No. 542, an antistatic layer is provided between the backing layer and the base, and an aziridine hardener can 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) Object of the invention The object of the invention is to provide a backing layer with good antistatic properties.

(D) Structure of the Invention In a silver halide film photosensitive material having a conductive polymer layer between a gelatin-containing backing layer and a film base, the conductive polymer is a combination of N-methylol (meth)acrylamide and styrene sulfonic acid. This is achieved using a silver halide film photosensitive material that is a polymer.

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 preferably 5% by weight or more and 70% by weight or less, more preferably 10% by weight or more and 60% by weight or less.

Preferably, the copolymer is produced by dissolving a mixture of P-styrene sulfonic acid or its alkali metal salt and N-methylol (meth)acrylamide in an alcohol/water mixed solvent, and in the monomer state, the mixture is dissolved in the medium. Polymerization is carried out in a system in which the polymer is soluble in the medium, but as the polymer is formed as the polymerization progresses, it 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 carrying out such polymerization, by making a soluble resin exist in the medium in advance, the precipitated polymer can be 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, 30 g of 5N-methylolacrylamide, and ethanol 2
00g and 100g of distilled water were added and dissolved at 70°C. When 1 g of AIBN was added at 75° C. under a nitrogen atmosphere to initiate polymerization, 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.

Sodium p-styrene sulfonate 70 g S,N-
30 g of methylol acrylamide and 5 g of 2-acrylamido-2-methylpropanesulfonic acid were added to a mixed solvent containing 150 g of ethanol and 150 g of distilled water at 70°C.
The polymerization was started by adding ABINl and Og at 75° C. under a nitrogen atmosphere. 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 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-
70 g of sodium styrene sulfonate, 30 g of N-methylolacrylamide 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 thermosetting antistatic agent obtained by the present invention can be prepared by forming a film alone on a support such as a film, for example at 50°C.
It is completely crosslinked within several hours under moderate heating conditions.

The conductive polymer of the present invention has 1rI! A coating amount of 0.1 to 5 g per solid content is preferred.

The conductive polymer layer may contain other binders as necessary.

The conductive polymer layer used in the present invention is located between the gelatin-containing backing layer and the film base; other locations are not preferred.

For example, if an antistatic layer is provided on the opposite side of the base through a backing layer, the film of the antistatic layer will not be sufficiently formed and the resistance will be high. Because it contains filter dye, dye removal becomes difficult and is not desirable. Furthermore, when an antistatic layer is provided between the emulsion layer and the film base, it is disadvantageous because the emulsion layer generally requires stronger adhesion than the back side because organic solvents are used to attach the stripping film. be.

Furthermore, if an antistatic layer is provided between the emulsion layer and the protective layer, or outside the protective layer from the film base, the antistatic layer will not be formed sufficiently, resulting in a high resistance value, which is undesirable. Furthermore, it is disadvantageous in terms of development progress and fixing speed.

Therefore, the antistatic polymer is most preferably located 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 a polymer layer alone or a conductive polymer layer alone, but in this case, since the emulsion layer and the protective layer are mainly composed of gelatin, curling becomes strong and this is not practical.

The amount of gelatin in the backing layer is 0.5 to 8 g per unit, preferably 1 to 5 g per unit. The backing layer may further contain the above-mentioned conductive polymers, other conductive polymers, water-soluble polymers, hardeners, matting agents, antihalation dyes, surfactants, and the like, as required.

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

(E) Example Example 1 I made the following solution.

Coating liquid for antistatic layer (I-a) - Distilled water 500 ml Backing liquid (r-b) (Hereinafter, blank) Dye (Dye (B-2) H4 NFI.

Dye (B-3) Coating liquid for emulsion (I-c) * 0° Double with 15μ monodisperse AgC1 emulsion Prepared by jet method.

In this 200g contains 100g of silver and 20μ of gelatin.

Coating liquid for protective layer (I-d) These coating liquids were coated per 1 d: 20 ml as an antistatic layer, 60 ml as a backing layer, 60 ml as an emulsion layer, and 20 ml as a protective layer. Each layer was applied one by one and heated at 50° C. for one day after each application.

The position of the antistatic polymer layer is (a) between the backing layer and the base, (b) the side away from the base across the backing layer, i.e. the outermost layer, (c) between the emulsion layer and the base, and (d) the emulsion layer and the protective layer. There are five types: between layers (e) above the protective layer, that is, the outermost layer. Furthermore, the one to which no antistatic layer was applied was designated as (f).

These heated samples were processed using a GR-14 automatic processor manufactured by Konishirokusha. Developed using MRA manufactured by Mitsubishi Paper Mills Co., Ltd.
CD-101, 35℃ 20 seconds, fixing with the same CF-901
, 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 ohms or less is considered a good level.

Two types of adhesion tests were conducted. One is the adhesion test on the back side, which involves making scratches on the surface of the film with a utility knife at 5-stitch intervals, applying water, rubbing vigorously with a tissue 10 times, and observing the marks. Adhesion of all samples was good with this method.

Another adhesion test was conducted using the base cut liquid used to attach the stripping film.

The base cut liquid was used only on the emulsion side and was not applied on the back coating side. The base cut liquid was manufactured by Dainippon Ink and Chemicals, and the emulsion surface was wetted with the liquid and gently rubbed three times with a tissue. A sample that peeled off completely was graded as ×, a sample that peeled off about half of the sample was graded as △, and a sample that peeled off slightly was graded as ○.

Regarding dye loss, the unexposed part of the processed sample is
0 sheets were stacked, and the viewing angle was judged as ○△×. ○ indicates good quality, △ indicates practical but slightly poor level, and × indicates unacceptable level.

These results are shown in Table 1.

(Left below) As shown in Table 1, when a copolymer of N-methylol (meth)acrylamide and styrene sulfonic acid is used as an antistatic layer, it is most preferable to position it between the backing layer and the base. Recognize.

Claims (1)

[Claims] In a silver halide film photosensitive material having a conductive polymer layer between a gelatin-containing backing layer and a film base, the conductive polymer is composed of a copolymer of N-methylol (meth)acrylamide and styrene sulfonic acid. Characteristic silver halide film photosensitive material.