Bathophenanthroline compound and process for preparing same

Abstract

A novel bathophenanthroline compound of the general formula [I] or [II] is provided wherein R1 and R2 may be the same or different and independently represent a linear, branched or cyclic, saturated or unsaturated hydrocarbon group, or a substituted or unsubstituted, saturated or unsaturated hydrocarbon group provided that at least one of R1 and R2 has at least two carbon atoms, and wherein Ar1 and Ar2 may be the same or different and independently represent a substituted or unsubstituted aryl group. A process for preparing the compound is also provided wherein bathophenanthroline and an organolithium compound are subjected to nucleophilic substitution reaction to obtain the compound of the above formula [I] or [II].

Description

BACKGROUND OF THE INVENTION This invention relates to a bathophenanthroline compound, which is adapted for use in an organic electroluminescent device (e.g. an organic electroluminescent device suitable as a display device or a light-emitting device such as a spontaneous light flat display, especially an organic electroluminescent color display using an organic thin film as an electroluminescent layer), and also a process for preparing the compound. In recent years, importance of interfaces between human beings and machines including multimedia-oriented commercial articles is exalted. For more comfortable and more efficient machine operations, it is necessary to retrieve information from an operated machine without failure simply, instantaneously and in an adequate amount. To this end, studies have been made on various types of display devices or displays. As machines are now miniaturized, there is an increasing demand, day by day, for miniaturization and thinning of display devi...

AI Technical Summary

Benefits of technology

An object of the invention is to provide a novel organic material, which is suitable for use as a carrier transport material capable of efficiently transporting electrons and blocking holes.

The bathophenanthroline compound of the invention can control carrier transportability depending on the type of substituent introduced into the molecule, and can thus be utilizable as a carrier transport material of various types of organic EL devices. The compounds have high glass transition point and high melting point and are stable electrically, thermally and / or chemically. In addition, the compounds are sublimable in nature, which is advantageous in that a uniform amorphous film can be readily formed according to a vacuum deposition process.

According to the preparation process of the invention, the bathophenanthroline compound of the invention can be efficiently prepared. It is preferred that in the course of the nucleophilic substitution reaction, carbanions are generated from the lithium compound and subsequently reacted with the bathophenanthroline.

Problems solved by technology

However, liquid crystal displays have the problems that they do not rely on spontaneous light and thus need a greater power consumption for back light drive than for liquid crystal drive, with the result that a service time is shortened when using a built-in battery, thus placing a limitation on their use.

Moreover, the liquid crystal display has another problem that it has such a narrow angle of field as not to be suitable for use as a large-sized display device.

Furthermore, the liquid crystal display depends on the manner of display using the orientation of liquid crystal molecules, and this is considered to bring about a serious problem that its contrast changes depending on the angle even within an angle of field.

However, since a TFT (thin film transistor) drive circuit is used, a difficulty is involved in making a large screen size owing to the pixel defects, thus being disadvantageous in view of the reduction in cost.

However, this system has the problem that its response speed is not enough to deal with a motion picture.

The plasma display device employs plasma emission in a low pressure gas for display and is suited for the purposes of a large size and large capacitance, but has the problem on thinning and costs.

In addition, an AC bias of high potential is required for its drive, and thus, the display is not suitable as a portable device.

Like the plasma display device, an AC bias drive is essential, for which several hundreds of volts are necessary, thus not being of practical use.

Since inorganic materials are used for this purpose, it has been difficult to control emission wavelengths depending on the molecular design or the like.

Thus, it is believed that full color display is difficult.

However, organic materials that satisfy the above requirement and the efficient manufacture of these materials have never been found yet.

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