Organic thin film electroluminescent device

An organic thin film electroluminescent device comprising:

• an anode;
• a hole transport layer in contact with said anode, the hole transport layer having a first energy band gap;
• a potential barrier layer in contact with the hole transport layer, said potential barrier layer having a second energy band gap which is larger than said first energy band gap;
• a light emission layer in contact with said potential barrier layer, said light emission layer having a third energy band gap which is smaller than said second energy band gap;
• and
• a cathode in contact with said light emission layer, wherein the hole transport layer is made of a material containing at least a ditriphenylaminestyryl derivative expressed by the following formula:
• ##STR1377## where A is one selected from the group consisting of substituted alkylidene groups having not less than 10 carbon atoms, non-substituted alkylidene groups having not less than 10 carbon atoms, cycloalkylidene groups, oxygen atom, sulfur atom, substituted amino groups and non-substituted amino groups;
• where Ar.sup.1, Ar.sup.3, Ar.sup.4 and Ar.sup.5 are one selected from the group consisting of substituted arylene groups and non-substituted arylene groups;
• where Ar.sup.2 and Ar.sup.6 are one selected from the group consisting of substituted aryl groups and non-substituted aryl groups;
• and where X and Y are substituted groups expressed by the formula:
• ##STR1378## where Ar.sup.7 and Ar.sup.8 are one selected from the group consisting of substituted aryl groups and non-substituted aryl groups;
• and where R.sup.1 is one selected from the group consisting of hydrogen atom, halogen atom, hydroxyl groups, substituted amino groups, non-substituted amino groups, substituted alkoxy groups, non-substituted alkoxy groups, substituted alkyl groups having 1-6 carbon atoms, and non-substituted alkyl groups having 1-6 carbon atoms.