Barrier free stable quantum dot film

Abstract

A barrier free quantum dot particles film includes a free standing layer comprising shielded quantum dot particles; wherein the shielded quantum dot particles are formed by shielding quantum dot particles by at least one shielding method; wherein the shielded quantum dot particles are characterized in resisting at least one condition selected from the group consisting of high temperature, high humidity and water; and wherein the shielded quantum dot particles are dispersed in an acrylate adhesive. A method of fabricating a barrier free quantum dot particles free standing film is also disclosed. The method of fabrication of shielded quantum dot particles film on a light emitting diode (LED) lens is also disclosed.

What is claimed is: 
     
         1 . A barrier free quantum dot particles film, comprising:
 a free standing quantum dot particles layer comprising shielded quantum dot particles and at least two outer layers,   wherein the free standing quantum dot particles layer is sandwiched between the at least two outer layers;   wherein the shielded quantum dot particles are formed by shielding quantum dot particles by at least one shielding method;   wherein the shielded quantum dot particles are dispersed in an adhesive comprising an acrylate adhesive, a silicone adhesive, a thermoplastic adhesive, or an UV cured adhesive;   wherein each of the at least two outer layers is a film selected from the group consisting of polyethylene terephthalate (PET) film, a polyethylene naphthalate (PEN) film and a polyacrylonitrile (PAN) film; and   wherein a water vapor transmission rate (WVTR) and an oxygen transmission rate (OTR) for each of the at least two outer layers is within a range of 1-10 g/m 2  d and 50-200 cm 3 /m 2  d, respectively.   
     
     
         2 . The barrier free quantum dot film according to  claim 1 , wherein the quantum dot particles selected from a group consisting of CdSe, ZnS, CdZnS, MAPbX 3  (MA=methylammonium; X═Cl, Br, I), and combinations thereof; wherein size of the quantum dot particles is within a range of 4 nm to 8 nm; and wherein the quantum dot particles are hydrophobized with hydrophobic ligand comprising one or more of C3-C21 aliphatic, branched, cyclic and aromatic thiol. 
     
     
         3 . The barrier free quantum dot film according to  claim 1 , wherein the shielding method comprises at least one of a house shielding method, a ligand shielding method and a jacket shielding method. 
     
     
         4 . The barrier free quantum dot film according to  claim 3 , wherein the house shielding method comprises encapsulating the quantum dot particles by swelling and shrinking of carrier polymers in a solvent; wherein the swelling is carried out by heating the carrier polymers; wherein the shrinking is carried out by cooling of the carrier polymers; wherein the encapsulating of the quantum dot particles is controlled by sonicating and further evaporating excess solvent from the carrier polymers; wherein encapsulation efficiency of the carrier polymers is within a range of 5 to 20%; and wherein the house shielding method is characterized in providing moisture resistance property to the shielded quantum dot particles. 
     
     
         5 . The barrier free quantum dot film according to  claim 3 , wherein the house shielding method comprises adding crosslinked polymer beads as quantum dot carriers; wherein the crosslinked polymer beads comprises at least one of polystyrene and polymethyl methacrylate; wherein the crosslinked polymer beads are crosslinked by a crosslinker selected from the group consisting of divinylbenzene, N,N′-Methylene-bis-acrylamide, and ethylene glycol di-methacrylate crosslinker; wherein a size of the crosslinker is within a range of 100 nm to 5 μm; and wherein an amount of the crosslinker in a dispersion is within a range of 1 to 5% wt. 
     
     
         6 . The barrier free quantum dot film according to  claim 3 , wherein the ligand shielding method comprises encapsulating the quantum dot particles with a surfactant ligand co-system in a form of liquid, grease or paste; wherein the surfactant ligand co-system comprises a surfactant and a ligand; and wherein the ligand shielding method provides surface rigidity and extra stability to the quantum dot particles. 
     
     
         7 . The barrier free quantum dot film according to  claim 6 , wherein the surfactant is selected from one of the following:
 a block copolymer selected from the group consisting of poly(ethylene glycol)-block-poly(propylene glycol)-block-poly(ethylene glycol), poly(propylene glycol)-block-poly(ethylene glycol)-block-poly(propylene glycol), and polystyrene-block-poly(acrylic acid);   a copolymer selected from the group consisting of poly(methyl methacrylate-co-methacrylic acid), and poly(styrene)-co-methacrylic acid; and   a non-ionic surfactant selected from the group consisting of polyethylene glycol oleyl ether, polyoxyethylene (5) nonylphenylether, and polyethylene-block-poly(ethylene glycol);   wherein the surfactant is present in an amount within a range of 1-10% wt;   wherein the ligand is selected from the group consisting of Pluronic P123, octanethiol, C3-C21 aliphatic thiols, branched thiols, cyclic thiols, aromatic thiol, C3-C21 aliphatic amines, branched amines, cyclic amines and aromatic amines; and   wherein the ligand is present in an amount within a range of 1-10% wt.   
     
     
         8 . The barrier free quantum dot film according to  claim 3 , wherein the jacket shielding method comprises core/shell shielding the quantum dot particles with a multi-shell coating on metal-alloyed cores of the quantum dot particles; wherein the multi shell coating comprises a coating layer of 1-5 shells; wherein a total size of the shielded quantum dot particles ranges from 8 nm to 20 nm, a size of the metal-alloyed core ranges from 4 nm to 8 nm, and a thickness of the multi-shell coating ranges from 2 nm to 6 nm; and wherein the jacket shielding method provides thermal resistant properties to the shielded quantum dot particles and wherein the metal-alloyed core is made of at least one metal alloy selected from the group consisting of CdSe, ZnSe, CdZnSeS, CdTe, and MAPbX3 (MA=methylammonium; X═Cl, Br, I); and the multi-shell coating is made of at least one of ZnS and CdZnS.