JPH03217464A - Compositions with improved antistatic properties - 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 [Industrial Field] The present invention relates to compositions with improved antistatic properties. Such a composition can be used, for example, as an antistatic coating for photographic light-sensitive materials.

[Prior Art and its Problems] Conventionally, antistatic methods include a method of vapor depositing or sputtering a metal or conductive metal oxide onto a target substrate, a method of coating an ion conductive polymer, and the like. Methods using vapor deposition and sputtering use a vacuum system, which increases manufacturing costs.

On the other hand, it is known that methods using ion-conducting polymers have drawbacks such as the ability to prevent static electricity changing depending on humidity. Recently, there have also been examples of polymerizing aromatic compounds such as pyrrole in a polymer emulsion by chemical oxidation to produce polymeric compounds containing conductive polymers such as voripyrrole. However, in this case, the polymer compound is a polymer emulsion and is granular.

In order to ensure rapid electron transfer, an important condition is that the polymer particles be adjacent to each other when the film is formed. For this reason, in order to form a layer with good antistatic ability, when another polymer having film-forming ability is used as a binder, the concentration must be above a certain level. For example, when an attempt is made to disperse it in a binder such as gelatin, there is a drawback that the amount of binder cannot be increased because the antistatic ability decreases depending on the amount of binder.

[Object of the Invention] The object of the present invention is to provide a composition that has excellent antistatic properties and is unaffected by changes in humidity, and furthermore, to provide a composition that has antistatic properties that are not affected by changes in humidity even when a relatively large amount of binder is used. The object of the present invention is to provide a composition having excellent antistatic properties that are free from electrification.

[Structure of the Invention] The present invention is achieved by using an ionic antistatic agent and a polymer compound having electron conductivity in combination.

What is used as the ionic antistatic agent of the present invention is:
There are no particular restrictions on cationic, anionic, or amphoteric types as long as they are water-soluble and can be adjusted in pH. for example,
Examples include sodium polystyrene sulfonate, polycellulose sulfate, sodium polystyrene sulfonate-maleic acid, polydimethyldiallylammonium chloride, and polystyrene sulfonate ammonium salt.

The electronically conductive polymer compound used in the present invention is
Those obtained by chemical oxidative polymerization using a polymer emulsion and an oxidizing agent of an aromatic compound are preferred. It may be obtained by other methods (eg, gas phase polymerization method, electrochemical polymerization method).

There are no particular restrictions on this polymer emulsion, and known materials can be used as appropriate, but examples include esters (for example, esters of vinyl alcohol and saturated acids such as acetic acid and stearic acid).

Esters with unsaturated acids such as acrylic acid and methacrylic acid. esters of saturated alcohols and unsaturated acids such as acrylic acid), acrylamide, methacrylamide, unsaturated N-monosubstituted amides (e.g. N-methylacrylamide), ethylenically unsaturated compounds (e.g. ethylene),
Unsaturated acids (e.g. methacrylic acid), unsaturated ethers (
For example, copolymers and homopolymers of methyl vinyl ether), unsaturated nitriles (e.g. acrylonitrile), vinylidene compounds (e.g. vinylidene chloride), vinyl compounds (e.g. vinyl chloride), and sulfonic acid Examples include those having a group, a carpoxyl group, etc. There are no particular restrictions on the method for producing this polymer emulsion. The content of polymer particles in the polymer emulsion is preferably from 5 to 40% by weight.

Next, there are no particular restrictions on aromatic compounds as long as they can be oxidatively polymerized to obtain electrical conductivity.For example, aromatic hetero compounds (e.g., pyrrole, thiophene and their derivatives), aromatic amino compounds (e.g., aniline and its derivatives, diphenylamine), and aromatic hydrocarbon compounds (eg, benzene).

Oxidizing polymerization catalysts are used as oxidizing agents, such as peroxides (hydrogen peroxide, potassium peroxide, etc.), oxyacids (hypochlorites), and metal salts (ferric chloride). do. This oxidizing agent may be used before or after dropping the aromatic compound into the polymer emulsion, but preferably before dropping the aromatic compound.

Although these reaction systems may be carried out at room temperature, they are preferably carried out while being cooled to -10 to 0°C.

The composition of the present invention preferably contains a binder, and any known binder can be used as appropriate. Examples include gelatin, polyvinyl alcohol, cellulose derivatives, and various starches, with gelatin being particularly preferred.

When these ionic antistatic agents, electronically conductive polymer compounds, and binders are used together, the pH is significantly different, which may cause aggregation when mixed. Therefore, it is desirable to adjust the pH in advance.

The ionic antistatic agent has a solid content ratio of 0.1 to 100 parts by weight, particularly 0.5 to 100 parts by weight, per 1 part by weight of the electronically conductive polymer compound.
It is preferable to add it in a proportion of 50 parts by weight. Further, the binder may be added in a solid content ratio of 0.01 to 10 parts by weight, particularly 0.01 to 1 part by weight, per 1 part by weight of the electron conductive polymer compound and the ionic antistatic agent. preferable.

Although there is no particular restriction on the mixing ratio of the ionic antistatic agent and the binder, the more the ionic antistatic agent is contained, the more susceptible to humidity changes will be.

The antistatic composition of the present invention can be applied to silver halide photographic materials for general use or printing plates, which are supported by plastic films such as polyethylene terephthalate or polycarbonate, or resin-coated paper coated with polyethylene, polypropylene, etc. on both sides of the paper. It is effectively used as a composition for antistatic layer.

[Examples] Next, the present invention will be described in more detail based on Examples. In addition, unless otherwise specified in the examples, parts indicate parts by weight, and % indicates weight %, respectively.

Example 1 20 parts of 2-acrylamido-2-methylpropanesulfonic acid was dissolved in 430 parts of water. Since this aqueous solution is a strong acid, it was neutralized using an aqueous sodium hydroxide solution. Next, 7 parts of methyl methacrylate, 6 parts of n-butyl acrylate
A monomer mixture solution was prepared by mixing 0 part of methacrylic acid and 1 part of methacrylic acid, and 3 parts of this was added to the above neutralized monomer solution and stirred while passing nitrogen gas. Thereafter, 43 parts of a 10% aqueous solution of potassium persulfate was added to initiate polymerization at 80°C. After 30 minutes, the remaining monomer mixture was reacted for 3 hours using a dropping funnel, and a milky white polymer emulsion with stable dispersion was obtained. This polymer emulsion was placed in a cellophane tube for dialysis and dialyzed. The solid content concentration of the polymer after dialysis was 8%.

To 150 parts of the polymer emulsion thus obtained, 7.5 parts of ammonium persulfate dissolved in 75 parts of water was added, stirred well, and then 7.5 parts of pyrrole was added to ensure sufficient reaction. The mixture was stirred for more than half a day. Cool the polymer emulsion, water, and pyrrole well in advance.
The reaction was also carried out while cooling. The pH of the produced polymer compound with electronic conductivity was approximately 2, indicating a strong acid. Therefore, an aqueous sodium hydroxide solution was added until the pH reached 6 for neutralization.

For 60 parts of the electron conductive polymer compound solution (hereinafter referred to as component A) with a solid content concentration of 4.7% obtained in this way, a commercially available ionic antistatic agent Chemistat with a solid content concentration of 33% was added. (polystyrene sulfonic acid type manufactured by Sanyo Chemical Industries ■, hereinafter referred to as Component B) and 10, 20, and 30 parts, respectively, and a gelatin solution with a solid content concentration of 6% (hereinafter referred to as Component B) as a binder.
Component C) were mixed in proportions of 30, 20, and 10 parts, respectively, and thoroughly stirred to form a polymer compound with electronic conductivity,
An antistatic composition containing an ionic antistatic agent and a binder was prepared.

This antistatic composition was coated on a water-soluble undercoated PET film to a thickness of about 2 μm and dried.

Table 1 shows the surface resistance of this coating film when the humidity was varied at 20°C. The surface resistance was measured using a high resistance resistivity meter manufactured by Mitsubishi Yuka Co., Ltd. Furthermore, the humidity was controlled for over 1 hour under all temperature and humidity conditions.

Comparison (1) Ionic antistatic agent Chemistat (component B
) was applied to a thickness of approximately 2 μm.

Comparison (2) Electron conductive polymer compound solution (component A) 60
and 40 parts of gelatin solution (component C) were mixed and coated to a thickness of about 2 μm.

(The following is a blank space) From Table 1, the samples using the ionic antistatic agent of the present invention in combination with the antistatic agent having electron conductivity are significantly superior in antistatic properties compared to the comparative samples. It was also observed that it was least affected by humidity changes.

Example 2 15 parts of component B was added to 40 parts of component A used in Example 1.
, 30 and 45 parts of component C45, and 30 and 15 parts of component C45, respectively, to prepare an antistatic composition containing an electronically conductive polymer compound, an ionic antistatic agent, and a binder.

This antistatic composition was coated and dried on a water-soluble undercoated PET film to a thickness of about 2 μm.

Table 2 shows the surface resistance of this coating film when the humidity was varied at 20°C. Measurement and humidity control were conducted in the same manner as in Example 1.

Comparison (3). Ionic antistatic agent Chemistat (component B
) was applied to a thickness of approximately 2 μm.

Comparison (4): Electron conductive polymer compound solution (component A) 4
0 parts and 60 parts of gelatin solution (component C) were mixed and applied to a thickness of about 2 μm.

(The following is a blank space) As is clear from the examples, the samples of the present invention have superior antistatic properties compared to the reference samples, and are less susceptible to changes in humidity.

[Effects of the Invention] As described above, the present invention can provide a composition that has excellent antistatic properties and is resistant to changes in humidity. Further, by using an ionic antistatic agent in combination, the electron conductive polymer compound can be effectively utilized at a low concentration.

Claims (1)

[Claims] 1. An antistatic composition containing an ionic antistatic agent and a polymer compound with electron conductivity.