COMPOSITION COMPRISING SEMICONDUCTING LIGHT EMITTING NANOPARTICLES

1 . A composition comprising at least:

i) a semiconducting light emitting nanoparticle;

ii) a macromolecular compound comprising at least an anchoring group;

iii) an organic additive.

2 . The composition of claim 1 , wherein the organic additive is defined by formula (Ia) or (Ib)

M-(X—Y) 2   (Ia);

X—Y  (Ib),

wherein

M is a divalent metal ion,

X is a hydrocarbon chain, and

Y is a functional group.

3 . The composition according to claim 2 , wherein at least one of the following applies:

a) M is selected from the group consisting of Zn 2+ , Mg 2+ and Cd 2+ ;

b) Y is selected from the group consisting of carboxylate, carbamate, xanthate, phosphonate, phosphate, thiolate;

or a combination of two or more thereof.

4 . The composition of claim 1 , wherein the organic additive is defined by formula (II),

wherein

M is selected from the group consisting of Zn 2+ , Mg 2+ and Cd 2+ ;

R 1 and R 2 can be same or different, linear or branched, and each R 1 , R 2 is selected from the group consisting of an alkyl having a chain of 1 to 16 carbons atoms or an alkenyl group having a chain of 1 to 15 carbon atoms.

5 . The composition of claim 1 , wherein the organic additive comprises a Zinc carboxylate.

6 . The composition of claim 1 , wherein the at least one anchoring group of the macromolecular compound is ionic.

7 . The composition of claim 1 , wherein the at least one anchoring group of the macromolecular compound is selected from the group consisting of phosphine group, phosphine oxide group, phosphate group, phosphonate group, thiol group, tertiary amine, carboxyl group, hetero cyclic group, silane group, sulfonic acid, hydroxyl group; or a combination of two or more thereof.

8 . The composition of claim 1 , wherein the macromolecular compound has a number average molecular weight of at least 1,000 g/mol.

9 . The composition of claim 1 , wherein the macromolecular compound is based on a copolymer.

10 . The composition of claim 9 , wherein the copolymer is selected from the group consisting of graft copolymer, block copolymer, alternating copolymer, random copolymer.

11 . The composition of claim 1 , wherein the macromolecular compound comprises at least one acrylate.

12 . The composition of claim 1 , wherein the composition further comprises at least an organic phase.

13 . The composition of claim 1 , wherein the composition further comprises a matrix polymer.

14 . The composition of claim 13 , wherein the matrix polymer is selected from an acrylate, an epoxy resin, a polyurethane and a polysiloxane.

15 . A method of manufacturing a composition with improved quantum yield, comprising at least these steps:

a/ Manufacturing a mixture by at least these steps:

1/ Providing a semiconducting light emitting nanoparticle,

2/ Adding a macromolecular compound comprising at least an anchoring group;

3/ Adding an organic additive

which forms the composition according to claim 1 ;

b/ Subjecting the mixture from step (a) to irradiation with light of a wavelength selected from a range of 300 to 600 nm having an intensity in the range from 0.025 to 1 W/cm 2 to obtain the composition.

16 . A method of manufacturing a layered composite comprising at least these steps:

(A) Manufacturing a mixture by at least these steps:

(1) Providing a semiconducting light emitting nanoparticle;

(2) Adding a macromolecular compound comprising at least an anchoring group;

(3) Adding an organic additive

which forms the composition according to claim 1 ;

(B) Applying the mixture to a substrate in order to form a layer; and

(C) Drying the layer on the substrate.

17 . The method of claim 16 , wherein the at least one of the following features applies:

a/ The mixture obtained from step (A) is irradiated with light prior to step (B);

b/ The layer on the substrate is irradiated with light in a step (D) following to step (C);

wherein the light has a wavelength selected from a range of 300 to 600 nm having an intensity in the range from 0.025 to 1 W/cm 2 to obtain the composition.

18 . A layered composite obtainable or obtained by the method of claim 16 .

19 . A layered composite comprising:

α) a substrate;

β) at least a layer comprising

a. a semiconducting light emitting nanoparticle;

b. a macromolecular compound comprising at least an anchoring group; and

c. an organic additive

wherein thus the layer comprises the composition according to claim 1 .

20 . An optical device comprising a layered composite according to claim 18 .

21 . A method to improve the emission efficiency of a semiconducting light emitting nanoparticle, comprising adding an organic additive to said semiconducting light emitting nanoparticle.

22 . A method to improve the quantum yield of a composition comprising a semiconducting light emitting nanoparticle and an organic additive, comprising irradiating said composition with a light of a wavelength in the range from 300 to 600 nm having an intensity in the range from 0.025 to 1 W/cm2.