Printing composition, electronic device comprising same and preparation method for functional material thin film

1. A printing formulation comprises at least one functional material and at least one inorganic ester solvent having the following general formula:

wherein,

R 1 , R 2 , R 3 are each independently selected from the group consisting of H; D; a linear alkyl, alkoxy group, or thioalkoxy group having 1 to 20 carbon atoms; a branched or cyclic alkyl, alkoxy group or thioalkoxy group, or silyl group having 3 to 20 carbon atoms; a substituted ketone group having 1 to 20 carbon atoms; an alkoxycarbonyl group having 2 to 20 carbon atoms; an aryloxycarbonyl having 7 to 20 carbon atoms; cyano group, carbamoyl, haloformyl, formyl, isocyano group, isocyanate group, thiocyanate group, or isothiocyanate, hydroxy, nitro, CF 3 , Cl, Br, and F; a substituted or unsubstituted aromatic or heteroaromatic ring group having 5 to 40 annular atoms; or an aryloxy group or heteroaryloxy group having 5 to 40 annular atoms, or a combination thereof, wherein the inorganic ester solvent has a boiling point greater than or equal to 150° C., and can be evaporated from a solvent system to form a functional material film,

wherein the functional material is a quantum dot material.

2. The printing formulation according to claim 1 , wherein the inorganic ester solvent has a viscosity ranging from 1 cPs to 100 cPs at 25° C.

3. The printing formulation according to claim 1 , wherein the inorganic ester solvent has a surface tension ranging from 19 dyne/cm to 50 dyne/cm at 25° C.

4. The printing formulation according to claim 1 , wherein the inorganic ester solvent is selected from the group consisting of alkyl borate or alkyl phosphate.

5. The printing formulation according to claim 1 , wherein the inorganic ester solvent is selected from tributyl borate, triamyl borate, trimethyl phosphate, triethyl phosphate, tributyl phosphate, tri(2-ethylhexyl) phosphate, triphenyl phosphate, diethyl phosphate, dibutyl phosphate, di(2-ethylhexyl) phosphate, or a combination thereof.

6. The printing formulation according to claim 1 , wherein the printing formulation further includes at least one other solvent, and the inorganic ester solvent accounts for more than 50% of the total weight of the mixed solvent.

7. The printing formulation according to claim 1 , wherein the functional material is an inorganic nano-material.

8. The printing formulation according to claim 1 , wherein the quantum dot material has a particle size having a monodisperse size distribution and a shape selected from spheres, cubes, rods, or branched structures.

9. The printing formulation according to claim 1 , wherein the quantum dot material is a light-emitting quantum dot material, which has an emission wavelength between 380 nm and 2500 nm.

10. The printing formulation according to claim 1 , wherein the printing formulation further includes an inorganic functional material selected from a binary semiconductor compound or a multinary semiconductor compound of Group IV, II-VI, II-V, III-V, IV-VI, II-IV-VI, and II-IV-V of the periodic table, or a mixture thereof.

11. The printing formulation according to claim 1 , wherein the printing composition comprises the functional material in a weight ratio in the range of 0.3% to 30%, and the inorganic ester solvent is in a weight ratio from 70% to 99.7%.

12. An electronic device comprising a functional layer, wherein said functional layer is prepared by printing or coating with the printing formulation according to claim 1 , and the inorganic ester solvent can be evaporated from the solvent system to form a functional material film.

13. The electronic device according to claim 12 , wherein the electronic device is selected from quantum dot light emitting diodes, quantum dot photovoltaic cells, quantum dot light emitting electrochemical cells, quantum dot field effect transistors, quantum dot light emitting field effect transistors, quantum dot lasers, quantum dot sensors, organic light-emitting diodes, organic photovoltaic cells, organic light-emitting electrochemical cells, organic field effect transistors, organic light-emitting field effect transistors, organic lasers, or organic sensors.

14. A method for preparing a functional material film, wherein the printing formulation according to claim 1 is coated on a substrate by a printing or coating method, wherein the printing or coating method is selected from ink-jet printing, nozzle printing, typography, screen printing, dip coating, spin coating, blade coating, roll printing, torsion printing, lithography, flexography, rotary printing, spray printing, brush coating, pad printing, or slit type extrusion coating.