KR102609527B1 - Compound for Photo-crosslinkable Quantum Dot Ligand, Photo-crosslinkable Quantum Dot, Photoresist Composition Comprising the Same and Electric Device using the Same - Google Patents

Abstract

The present invention is a compound for photocrosslinkable quantum dot ligands that is bound to the surface of quantum dots,
A photo-crosslinkable portion (A) capable of self-crosslinking by light in the absence of a photoinitiator;
Anchor portion (C) coupled to the quantum dot surface; and
A body portion (B) connecting the photocrosslinkable portion (A) and the anchor portion (C); a compound for a photocrosslinkable quantum dot ligand bonded to the surface of the quantum dot, including a photocrosslinkable quantum dot, a photoresist composition containing the same, and the same. Provides electronic devices using
In the above, the structures of the photo-crosslinkable portion (A), body portion (B), and anchor portion (C) are as defined in claim 1.

Description

Compound for photo-crosslinkable quantum dot ligand, photo-crosslinkable quantum dot, photoresist composition containing the same, and electronic device using the same {Compound for Photo-crosslinkable Quantum Dot Ligand, Photo-crosslinkable Quantum Dot, Photoresist Composition Comprising the Same and Electric Device using the Same}

The present invention relates to a compound for a photo-crosslinkable quantum dot ligand capable of self-crosslinking by light even in the absence of a photoinitiator, a photocrosslinkable quantum dot to which the compound for a photocrosslinkable quantum dot is bonded to the surface, a photoresist composition containing the same, and an electronic device using the same. It's about.

In general, color filters applied to displays are formed through a patterning process in which the desired pattern is formed through an exposure process using a photomask using a photosensitive resist composition, and the non-exposed areas are dissolved and removed through a development process, making them a material for color filters. It is alkali soluble and requires high sensitivity, adhesion to the substrate, chemical resistance, and heat resistance. However, since the curing reaction is usually not sufficient through the exposure process alone, a step of thermal curing for a certain period of time at a high temperature of 200 ℃ or higher is required to obtain the required properties, which has limited applications that require low-temperature processes such as electronic paper and OLED.

In order to develop photosensitive resin compositions for color filters that require relatively low-temperature processes such as electronic paper and OLED, efforts were made to supplement the insufficient curing properties by adding epoxides and peroxides to the compositions, but the degree of curing was not sufficient, leading to low reliability. There was a problem with it being low. This phenomenon occurs because coloring materials such as pigments or dyes absorb light energy competitively with the photopolymerization initiator, and it is difficult to obtain sufficient initiation efficiency by removing the radicals generated by the pigments and dyes, resulting in curing of the photopolymerizable monomer. The rate decreases compared to the case where color materials are not used. To solve this problem, recent efforts have been made to develop photosensitive resin compositions that can significantly improve reliability, such as chemical resistance and heat resistance, by using materials such as quantum dots instead of color materials such as existing dyes or pigments. there is.

Quantum dots have a large surface area per unit volume due to their size of several to tens of nanometers (nm), and most atoms exist only on the surface of the nanocrystal, showing a unique behavior called quantum effect. These quantum dots have a ligand attached to them to stabilize dangling bonds on the surface of the quantum dots, thereby providing stability to the quantum dots themselves and at the same time providing dispersibility of the quantum dots, which are inorganic particles, in a hydrophobic solvent. The ligand system of quantum dots synthesized by conventional methods inevitably consists of a long hydrophobic alkyl chain and a hydrophilic head group (carboxylic aicd, phosphine, amine, phosphineoxide, etc.).

However, since the ligand system cannot be changed as desired according to the quantum dot synthesis conditions, quantum dots are dispersed only in hydrophobic non-polar solvents, which poses a significant limitation in applying quantum dots to the display process. Currently, most of the ligands of InP-based quantum dots are composed of oleic acid, trioctylamine, and trioctylphosphine (-oxide), and dispersible solvents include hexane, cyclohexane, chloroform, and toluene, but all of these have human toxicity issues during the display process. It is designated as a prohibited substance, and the physical properties required for the process (melting point, boiling point, vapor pressure, compatibility with other solvents, etc.) are also not correct.

Korean Patent No. 10-1993679 and Korean Patent No. 10-1628065 disclose quantum dots with specific ligands bound to the surface, but their compatibility is low, resulting in poor dispersibility, poor stability and reliability, and poor stability and reliability over time. Accordingly, the problem of reduced quantum efficiency is not being solved.

Accordingly, attempts have been made to add monomers or binder resins with specific functional groups in the crude photosensitive resin composition containing quantum dots to increase the light conversion rate and process maintenance rate. However, most of these monomers or binder resins are mixed in the crude solution in a single molecule state and cannot fundamentally block the escape of ligands from the quantum dot surface, resulting in a decrease in quantum efficiency.

<Prior art literature>

Korean Patent No. 10-1993679

Korean Patent No. 10-1628065

The purpose of the present invention is to solve the above problems of the prior art and technical problems that have been requested in the past.

The purpose of the present invention is to provide a compound for photocrosslinkable quantum dot ligands that self-crosslinks by light even in the absence of a photoinitiator, photocrosslinkable quantum dots, and a pattern composition containing quantum dots that exhibits excellent dispersion stability and light conversion rate using the same.

Another object of the present invention is to ultimately provide an electronic device with excellent electrical properties using a pattern composition containing quantum dots.

The present invention,

A compound for photocrosslinkable quantum dot ligands that binds to the surface of quantum dots.

A photo-crosslinkable portion (A) capable of self-crosslinking by light in the absence of a photoinitiator;

Anchor portion (C) coupled to the quantum dot surface; and

It provides a compound for a photo-crosslinkable quantum dot ligand including a body portion (B) connecting the photocrosslinkable portion (A) and the anchor portion (C).

Here, the photocrosslinkable portion (A) is represented by the following structural formula 1,

[Structural Formula 1]

In structural formula 1,

X is O, S or NH;

Y is hydrogen, a halogen atom, substituted or unsubstituted C1-C4 alkyl; Substituted or unsubstituted C1-C4 alkoxy, substituted or unsubstituted C4-C6 aryloxy, substituted or unsubstituted C4-C6 heterocycloalkyl, -NO ₂ , -NR ₁ R ₂ , -COR ₁ , -CN or - SR ₁ ; Here, R ₁ and R ₂ are each independently hydrogen or C1-C3 alkyl; The substituent is a halogen element, C1-C3 alkyl or phenyl;

m is an integer from 1 to 5;

* is the binding site that binds to Y;

a is an integer from 1 to 3;

b is an integer from 0 to 2;

The heteroatom is one or more selected from N, O and S,

The body portion (B) is expressed by the structural formula 2 below,

[Structural Formula 2]

In structural formula 2,

R is substituted or unsubstituted C2-C20 alkyl, substituted or unsubstituted C2-C20 heteroalkyl, or R ₃ CO(O)R ₄ ; Here, R ₃ and R ₄ are each independently C1-C10 alkyl or C1-C10 heteroalkyl; The substituent is a halogen element or alkyl of C1-C3; The heteroatom is one or more selected from N, O and S;

*’ is a binding site that binds to the anchor portion (C),

The anchor portion (C) is expressed by the following structural formula 3,

[Structural Formula 3]

In structural formula 3,

n is an integer from 1 to 2, and

*’ is a binding site that binds to the body (B).

Specifically, the compound for the photo-crosslinkable quantum dot ligand may be expressed as follows.

In structural formula 1,

X is O, S or NH;

Y is hydrogen, a halogen atom, alkyl of C1-C3, alkoxy of C1-C3, aryloxy of C6, heterocycloalkyl of C4-C5, -NO ₂ , -NR ₁ R ₂ , -COR ₁ , -CN or -SR ₁ ; Here, R ₁ and R ₂ are each independently hydrogen or C1-C3 alkyl;

m is 1;

* is the binding site that binds to Y;

a is 1 or 2;

b is 0 or 1;

The heteroatom is one or more selected from N, O and S,

In structural formula 2,

R is C2-C11 alkyl, C2-C11 heteroalkyl or R ₃ CO(O)R ₄ ; Here, R ₃ and R ₄ are each independently C1-C5 alkyl or C1-C5 heteroalkyl; The heteroatom is one or more selected from N, O and S;

*’ is a binding site that binds to the anchor portion (C),

In structural formula 3,

n is 1 or 2 and

*’ is a binding site that binds to the body (B).

More specifically, the compound for the photo-crosslinkable quantum dot ligand may be one selected from the compounds of the following formulas 1 to 3.

[Formula 1]

[Formula 2]

[Formula 3]

Formulas 1 to 3 are the same or different from each other,

X is O, S or NH;

Y is hydrogen, a halogen element, C1 alkyl; C1 alkoxy, C6 aryloxy, C4-C5 heterocycloalkyl, -NO ₂ , -NR ₁ R ₂ , -COR ₁ , -CN or -SR ₁ ; Here, R ₁ and R ₂ are each independently hydrogen or C1-C2 alkyl;

m is 1;

The heteroatom is one or more selected from N, O and S,

R is C2-C11 alkyl, C2-C11 heteroalkyl or R ₃ CO(O)R ₄ ; Here, R ₃ and R ₄ are each independently C1-C5 alkyl or C1-C5 heteroalkyl; The heteroatom is one or more selected from N, O and S;

*' is the binding site where R and -(SH)n bind; and

n is 1 or 2.

In one embodiment, the compound of Formula 1 is a compound for photocrosslinkable quantum dot ligand, characterized in that at least one selected from compound group A expressed below:

[Compound group A]

In one example, the compound of Formula 2 may be one or more selected from compound group B shown below.

[Compound group B]

In one example, the compound of Formula 3 may be one or more selected from compound group C shown below.

[Compound group C]

The present invention also provides quantum dots; And it provides a photo-crosslinkable quantum dot comprising a compound for a photo-crosslinkable quantum dot ligand according to claim 1, which is bound to the surface of the quantum dot.

The quantum dots include MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al ₂ O ₃ , Al ₂ S ₃ , Al ₂ Se ₃ , Al ₂ Te ₃ , Ga ₂ O ₃ , Ga ₂ S ₃ , Ga ₂ Se ₃ , Ga ₂ Te ₃ , In ₂ O ₃ , In ₂ S ₃ , In ₂ Se ₃ , In ₂ Te ₃ , SiO ₂ , GeO ₂ , SnO ₂ , SnS, SnSe, SnTe, PbO, PbO ₂ , PbS, PbSe, PbTe, AlN, AlP, It contains a compound selected from the group consisting of AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, BP, Si and Ge, and can form a core/shell structure.

The present invention also provides a photoresist composition comprising photocrosslinkable quantum dots and a solvent.

The composition may include more than 0 to 0.1% by weight or less of a photoinitiator based on the total weight of the composition.

The present invention also provides an electronic device manufactured using the photoresist composition containing photocrosslinkable quantum dots.

The compound for photocrosslinkable quantum dots according to the present invention contains a photocrosslinkable conjugated functional group and can be self-crosslinked by light even in the absence of a photoinitiator, and excellent dispersion stability is achieved by using photocrosslinkable quantum dots containing the same. , it is possible to provide a pattern composition containing quantum dots that exhibits light conversion rate and reliability.

The photo-crosslinkable quantum dot ligand according to the present invention includes an anchor moiety expressed as a thiol group (-SH), and a pattern composition containing quantum dots that exhibits excellent production yield and manufacturing process can be provided by using photocrosslinkable quantum dots containing this. .

The present invention can ultimately provide an electronic device with excellent electrical properties and long lifespan using a pattern composition containing quantum dots.

Figure 1 is a cross-sectional schematic diagram and SEM photo of quantum dots prepared in Preparation Example 1;
Figure 2 shows the change in absorbance depending on the substitution % of the photocrosslinkable quantum dot ligand in Examples 2-3;
Figure 3 is a TGA graph according to 7% substitution of photocrosslinkable quantum dot ligands in Examples 2-3;
Figure 4 is an NMR graph according to 7% substitution of the photocrosslinkable quantum dot ligand in Example 2-3;
Figure 5 is an IR graph according to 7% substitution of the photocrosslinkable quantum dot ligand in Examples 2-3;
Figure 6 is a photograph of a photo-crosslinkable quantum dot thin film pattern using Example 2-3; and
Figure 7 shows the results of changes in optical properties of the photo-crosslinkable quantum dot thin film using Example 2-3.

The present invention is a compound for a photo-crosslinkable quantum dot ligand that is bonded to the surface of a quantum dot and expressed by the following general formula 1, comprising: a photo-crosslinkable portion (A) capable of self-crosslinking by light in the absence of a photoinitiator; Anchor portion (C) coupled to the quantum dot surface; And a body portion (B) connecting the photo-crosslinkable portion (A) and the anchor portion (C). It provides a compound for a photo-crosslinkable quantum dot ligand including a.

[General Formula 1]

Specifically, the photocrosslinkable portion (A) is represented by the following structural formula 1,

[Structural Formula 1]

In structural formula 1,

X is O, S or NH;

Y is hydrogen, a halogen element, substituted or unsubstituted C1-C4 alkyl, substituted or unsubstituted C1-C4 alkoxy, substituted or unsubstituted C4-C6 aryloxy, substituted or unsubstituted C4-C6 heterocycloalkyl, - NO ₂ , -NR ₁ R ₂ , -COR ₁ , -CN or -SR ₁ ; Here, R ₁ and R ₂ are each independently hydrogen or C1-C3 alkyl; The substituent is a halogen element, C1-C3 alkyl or phenyl;

m is an integer from 1 to 5;

* is the binding site that binds to Y;

a is an integer from 1 to 3;

b is an integer from 0 to 2;

The heteroatom is one or more selected from N, O and S.

In addition, the body portion (B) is expressed by the following structural formula 2,

[Structural Formula 2]

In structural formula 2,

R is substituted or unsubstituted C2-C20 alkyl, substituted or unsubstituted C2-C20 heteroalkyl, or R ₃ CO(O)R ₄ ; Here, R ₃ and R ₄ are each independently C1-C10 alkyl or C1-C10 heteroalkyl; The substituent is a halogen element or alkyl of C1-C3; The heteroatom is one or more selected from N, O and S;

*’ is a binding site that binds to the anchor portion (C).

In addition, the anchor portion (C) is expressed by the following structural formula 3,

[Structural Formula 3]

In structural formula 3,

n is an integer from 1 to 2, and

*’ is a binding site that binds to the body (B).

In the case of photoreactive functional groups such as acrylics/vinyls, a photocrosslinking reaction occurs through the generation of radicals as the end groups are cut by a photoinitiator. In other words, a photoinitiator such as acrylate undergoes a radical reaction through light irradiation, creating an environment for other curing reactions to occur. However, the photoinitiator remains as a residual component after the reaction is completed, causing a decrease in the resolution and chemical and electrical properties of the quantum dot-containing pattern.

On the other hand, the compound for photocrosslinkable quantum dot ligand according to the present invention contains a photocrosslinkable conjugated functional group (red boxed portion in Structural Formula 1 below), so that self-crosslinking can be achieved by light even in the absence of a photoinitiator. In other words, when irradiated with light, the photocrosslinkable conjugated functional group binds and hardens in the presence of adjacent photocrosslinkable conjugated functional group and/or hydrocarbon in a temporary excited state. Radicals are not generated, or even if they are generated, only a very small amount is generated and self-isolation occurs. Since cross-linking can occur, it is very stable, and using this, a pattern composition containing quantum dots that exhibits excellent dispersion stability, light conversion rate, and reliability can be provided.

[Structural Formula 1]

As an example, as can be seen in Reference Figures 1 to 3 below, self-crosslinking of the carbonyl moiety may be performed in the presence of a benzene ring and/or a hydrocarbon.

[Reference 1]

[Reference 2]

[Reference 3]

In the present invention, the photocrosslinkable conjugated functional group located in the photocrosslinkable portion (A) self-crosslinks by light even in the absence of a photoinitiator, but is affected depending on the structures of the body portion (B) and anchor portion (C). You can receive it. For example, if the body portion (B) contains “aryl” as an aromatic substituent having at least one ring with a shared pi electron field, a radical reaction may occur by participating as a photoinitiator.

Accordingly, the compound for a photo-crosslinkable quantum dot ligand according to the present invention can prevent such radical reactions from occurring by including a body portion (B) having a heteroatom-containing alkyl skeleton.

In addition, the photocrosslinkable quantum dot ligand compound according to the present invention has a thiol group (-SH) with good affinity for the quantum dot surface introduced into the anchor portion (C) that binds to the quantum dot surface, so that oleic acid on the quantum dot surface is easily substituted. (ligand exchange), the photo-crosslinkable quantum dots containing them have maximized dispersibility in solvents in the photoresist composition, and can provide excellent production yield and manufacturing processability.

Hereinafter, the terms used in this specification will be briefly explained.

The term “halogen” refers to elements belonging to group 17 of the periodic table, and may specifically include fluorine, chlorine, bromine, and iodine.

The term “alkyl” refers to an aliphatic hydrocarbon group. In the present invention, alkyl may be used as “saturated alkyl,” meaning that it does not contain any alkene or alkyne moieties. The alkyl may be branched, straight-chain or cyclic, and may also contain structural isomers, so for example, in the case of C3 alkyl, it may mean propyl, isopropyl.

The term “alkoxy” refers to an alkyl group as described above linked through an oxygen linkage (-O-).

The term “aryloxy” refers to a group bonded to any one carbon and oxygen forming an aromatic substituent. For example, when oxygen is bonded to a phenyl group, -OC ₆ H ₅ , -C ₆ H ₄ -O- It can be displayed as .

The term “heterocycloalkyl” refers to a substituent in which a portion of a fully saturated or partially unsaturated hydrocarbon ring of a carbon atom is replaced with oxygen, nitrogen, sulfur, etc.

The term “heteroalkyl” is a substituent in which part of an alkyl group is replaced with oxygen, nitrogen, sulfur, etc.

The term “substituted or unsubstituted” means that the target functional group is substituted or not substituted with another substituent, and if there is no such description, it is considered unsubstituted for convenience.

"R ₃ CO(O)R ₄ "contains a carboxyl group between R ₃ and R ₄ , and this carboxyl group may be located in the form of -OC(=O)- or -C(=O)O-. .

" *' " is a binding site where the body portion (B) and the anchor portion (C) combine, and may be one or more than two depending on the case.

Other terms may be interpreted as commonly understood in the field to which the present invention pertains.

As an example of the present invention,

The compound for the photo-crosslinkable quantum dot ligand is,

In structural formula 1,

X is O, S or NH;

Y is hydrogen, a halogen atom, C1-C3 alkyl; C1-C3 alkoxy, C6 aryloxy, C4-C5 heterocycloalkyl, -NO ₂ , -NR ₁ R ₂ , -COR ₁ , -CN or -SR ₁ ; Here, R ₁ and R ₂ are each independently hydrogen or C1-C3 alkyl;

m is 1;

* is the binding site that binds to Y;

a is 1 or 2;

b is 0 or 1;

The heteroatom is one or more selected from N, O and S,

In structural formula 2,

R is C2-C11 alkyl, C2-C11 heteroalkyl or R ₃ CO(O)R ₄ ; Here, R ₃ and R ₄ are each independently C1-C5 alkyl or C1-C5 heteroalkyl; The heteroatom is one or more selected from N, O and S;

*’ is a binding site that binds to the anchor portion (C),

In structural formula 3,

n is 1 or 2 and

*’ may be a binding site that binds to the body portion (B).

In another example of the present invention,

The compound for the photocrosslinkable quantum dot ligand may be one selected from the compounds represented by the following formulas 1 to 3.

[Formula 1]

[Formula 2]

[Formula 3]

Formulas 1 to 3 are the same or different from each other,

X is O, S or NH;

Y is hydrogen, a halogen atom, C1 alkyl, C1 alkoxy, C6 aryloxy, C4-C5 heterocycloalkyl, -NO ₂ , -NR ₁ R ₂ , -COR ₁ , -CN or -SR ₁ ; Here, R ₁ and R ₂ are each independently hydrogen or C1-C2 alkyl;

m is 1;

The heteroatom is one or more selected from N, O and S,

R is C2-C11 alkyl, C2-C11 heteroalkyl or R ₃ CO(O)R ₄ ; Here, R ₃ and R ₄ are each independently C1-C5 alkyl or C1-C5 heteroalkyl; The heteroatom is one or more selected from N, O and S;

*' is the binding site where R and -(SH)n bind; and

n may be 1 or 2.

In these compounds of formulas 1 to 3, the photo-crosslinkable conjugated functional group (red box) that self-crosslinks when irradiated with light is indicated as follows.

[Formula 1]

[Formula 2]

[Formula 3]

In detail, the compound of Formula 1 of the photo-crosslinkable quantum dot ligand compound may be one or more selected from compound group A expressed below.

[Compound group A]

In detail, the compound of Formula 2 of the photo-crosslinkable quantum dot ligand may be one or more selected from compound group B expressed below.

[Compound group B]

In detail, the compound of Formula 3 of the photo-crosslinkable quantum dot ligand may be one or more selected from compound group C expressed below.

[Compound group C]

Meanwhile, the present invention,

quantum dots; And it provides a photo-crosslinkable quantum dot containing a compound for the photo-crosslinkable quantum dot ligand bound to the surface of the quantum dot.

The photo-crosslinkable quantum dots according to the present invention are surface modified with the photo-crosslinkable quantum dot ligand compound, and have excellent quantum efficiency and dispersion stability in the photoresist composition, so they not only exhibit a high light conversion rate, but also form a cured film on the surface of the quantum dots during the exposure process of the photoresist. Reliability can be secured through formation.

Quantum dots forming the central particle in the photo-crosslinkable quantum dot according to the present invention include, for example, MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al ₂ O ₃ , Al ₂ S ₃ , Al ₂ Se ₃ , Al ₂ Te ₃ , Ga ₂ O ₃ , Ga ₂ S ₃ , Ga ₂ Se ₃ , Ga ₂ Te ₃ , In ₂ O ₃ , In ₂ S _{3 , In 2 Se 3 , In 2 Te 3 , SiO 2 , GeO 2 , SnO 2 , SnS , SnSe , SnTe} , PbO, PbO ₂ , PbS, PbSe, PbTe, AlN, AlP, AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, BP, Si and Ge, or one selected from the group consisting of Ge. It can be formed by a combination of .

Quantum dots constituting these central particles may have a core/shell structure, and each of the core and shell may include the compounds exemplified above. The compounds exemplified above may be included in the core or shell individually or in combination of two or more.

Meanwhile, the present invention,

A photoresist composition containing the photo-crosslinkable quantum dots and a solvent is provided.

The photoresist composition according to the present invention includes photo-crosslinkable quantum dots that are surface modified with the photo-crosslinkable quantum dot ligand compound and can be self-crosslinked by light in the absence of a photoinitiator. Therefore, not only does it exhibit high optical conversion rate due to excellent quantum efficiency and dispersion stability, but also ensures reliability through the formation of a cured film on the surface of the quantum dot during the photoresist exposure process. In other words, the photoresist process can be performed without a separate photosensitive material and photoinitiator using the photoresist composition according to the present invention.

On the other hand, when a thiol-based material is used as an additive and simply mixed into a photoresist composition, the additive, which is a single molecule, forms a kind of equilibrium state in which it repeatedly separates and recombines from the surface of the quantum dot in the crude composition state, and this process A decrease in quantum efficiency occurs, and after going through the pre-bake thermal process, the speed at which the thiol-based additive leaves and recombines from the surface of the quantum dot increases, and the resulting decrease in quantum efficiency also increases, ultimately reducing the light conversion rate. There are problems that can lead to degradation. Furthermore, as thiol and acrylate-based monomer react and the pattern formation process progresses, physical loss of ligands from the quantum dot surface increases, which may lower the light conversion rate after final post-bake.

Accordingly, the photo-crosslinkable quantum dot ligand compound according to the present invention has a thiol group (-SH) with good affinity with the quantum dot surface introduced into the anchor portion (C) that binds to the quantum dot surface, resulting in better dispersion stability and light conversion rate. It can be expressed.

The solvent is a common organic solvent for pattern formation in the photoresist process, for example, DMF, 4-Hydroxy-4-methyl-2-pentanone, One or more of ethylene glycol monoethyl ether, 2-Methoxyethanol, chloroform, chlorobenzene, toluene, tetrahydrofuran, dichloromethane, hexane, heptane, octane, nonane, and decane. However, it is not limited to this.

The photoresist composition according to the present invention may, in some cases, include a photosensitive material and participate in crosslinking and/or curing reactions upon exposure to light, thereby increasing the resolution of the quantum dot-containing pattern and the durability of the cured product.

The photosensitive material may be, for example, a multifunctional acrylate-based compound containing at least one of an acrylic group and a vinyl group, a multifunctional polyalkylene oxide, or a polysiloxane-based polymer, but is not limited thereto.

Specifically, the photosensitive material includes urethane acrylate, allyloxylated cyclohexyl diacrylate, bis(acryloxy ethyl)hydroxyl isocyanurate, and bis(acryloxy ethyl)hydroxyl isocyanurate. (Acryloxy neopentylglycol) adipate [Bis (acryloxy neopentylglycol) adipate], Bisphenol A diacrylate, Bisphenyl A dimethacrylate, 1,4-butanediol diacrylate ( 1,4-butanediol diacrylate), 1,4-butanediol dimethacrylate, 1,3-butylene glycol diacrylate (1,3-butyleneglycol diacrylate), 1,3-butyl 1,3-butyleneglycol dimethacrylate, dicyclopentanyl diacrylate, diethyleneglycol diacrylate, diethyleneglycol dimethacrylate, dipentaerythirol hexaacrylate, dipentaerythirol monohydroxy pentacrylate, ditrimethylolpropane tetraacrylate, ethylene glycol dimethacrylate, ( ethyleneglycol dimethacrylate), glycerol methacrylate, 1,6-hexanediol diacrylate, neopentylglycol dimethacrylate, neopentyl glycol hydroxypiba neopentylglycol hydroxypivalate diacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, phosphoric acid dimethacrylate, polyethylene glycol diacrylate (polyetyleneglycol diacrylate), polypropyleneglycol diacrylate, tetraethyleneglycol diacrylate, tetrabromobisphenol A diacrylate, triethyleneglycol divinylether ), triglycerol diacrylate, trimethylolpropane triacrylate, tripropyleneglycol diacrylate, tris(acryloxyethyl)isocyanurate ], phosphoric acid triacrylate, phosphoric acid diacrylate, acrylic acid propargyl ester, Vinyl teminated Polydimethylsiloxane, vinyl at the end Vinyl teminated diphenylsiloxane-dimethylsiloxane copolymer, Vinyl teminated Polyphenylmethylsiloxane, trifluoromethyl siloxane-dimethylsiloxane copolymer with a vinyl group at the end ( Vinyl teminated trifluoromethylsiloxane-dimethylsiloxane copolymer), diethylsiloxane-dimethylsiloxane copolymer with a vinyl group at the end (Vinylmethylsiloxane), polydimethylsiloxane with a monomethacryloxypropyl group at the end ( Examples include Monomethacryloyloxypropyl Terminated Polydimethyl siloxane, Monovinyl Terminated Polydimethyl siloxane, or Monoallyl-mono trimethylsiloxy terminated polyethylene oxide. It is not limited to this.

The content of the photosensitive material is not particularly limited, and may be appropriately selected considering the photocuring speed, the state of the photocured film, etc., and the number of photosensitive functional group bonds on the surface of the photosensitive quantum dot.

The photoresist composition according to the present invention may not contain a photoinitiator, but in some cases, it may contain a very small amount of photoinitiator to initiate crosslinking and/or curing reaction between quantum dots and/or photosensitive materials according to the present invention. .

For example, the content of the photoinitiator may be greater than 0 and 0.1% by weight based on the total weight of the composition. That is, in the photoresist composition according to the present invention, the photoinitiator is present in an amount of 0 or more to 0.1% by weight based on the total weight of the composition. If too much photoinitiator is included beyond this, it remains as a residual component after completion of the reaction, affecting the resolution and chemical and electrical properties of the quantum dot-containing pattern. It is undesirable as it may cause a decrease in .

The photoinitiator may be, for example, an acetophenone-based, benzoin-based, benzophenone-based, or thioxanthone-based material, but is not limited thereto.

Using this photoresist composition, a quantum dot-containing pattern can be formed by performing a photoresist process using a method commonly performed in the art. For example, after providing the photoresist composition to a substrate, a pattern containing quantum dots can be obtained through a patterning process in which the photoresist composition is selectively exposed to form a pattern, and the non-exposed portion is dissolved and removed through a development process. Since this process is widely known in the art, detailed description will be omitted below.

In addition, the present invention,

An electronic device manufactured using the photoresist composition containing photocrosslinkable quantum dots is provided.

The electronic device may be, for example, a light emitting device such as a display, a holography device, a laser, a sensor, a solar cell, or a transistor, but is not limited thereto.

Hereinafter, the present invention will be described with reference to examples. However, the following examples are intended to illustrate the present invention, and the scope of the present invention is not limited to these only.

Preparation Example 1: InP/ZnSe/ZnS core-shell quantum dot synthesis

0.4 mmol (0.058 g) of indium acetate, 1.2 mmol (0.30 g) of palmitic acid, and 20 mL of 1-octadecene were placed in a reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was changed to nitrogen. After heating to 280°C, a mixed solution of 0.2 mmol (58 μl) of tris(trimethylsilyl)phosphine (TMS3P) and 1.0 mL of trioctylphosphine was quickly injected and allowed to react for 10 minutes. The resulting quantum dots were purified twice with acetone and then dispersed in toluene at 100 mg/ml.

Then, 12 mmol of zinc acetate, 24 mmol of oleic acid, and 20 mL of trioctylamine were added to the reactor and heated to 120°C under vacuum. After 1 hour, the atmosphere in the reactor was changed to nitrogen, and the reactor was heated to 280°C. 1 mL of the previously synthesized InP core solution was added, followed by 3.0 mmol of selenium in trioctylphosphine (Se/TOP), and the final mixture was reacted at 320°C for 2 hours. Next, 6.6 mmol of sulfur (S/TOP) in trioctylphosphine was added, and the final mixture was reacted for 2 hours. Ethanol was added to the reaction solution quickly cooled to room temperature, centrifugation was performed, and the precipitate obtained was filtered under reduced pressure and dried under reduced pressure to obtain quantum dots with an InP/ZnSe/ZnS core-shell structure, which were then dispersed in chloroform at 100 mg/ml. Quantum dots with a maximum emission wavelength of 525 nm were synthesized.

Example 1-1: Synthesis of photocrosslinkable quantum dot ligand of Formula A-1

(Formula A-1)

5 g (23.1 mmol) of 4-chlorobenzophenone, 5.08 g (23.1 mmol) of undecan-1,11-dithiol, 6.3 g (45.6 mmol) of K ₂ CO ₃ and 50 ml of DMF were added to 100 ml RBF and heated at 60°C to react overnight. Excess water was added, extraction was performed with MC, and the organic layer was treated with MgSO ₄ . After filtering and removing the solvent using a rotary evaporator, 50 g of methanol was added, heated to 60°C, stirred for 30 minutes, and then cooled. Filtered to obtain the product.

H NMR (δ ppm; CDCl ₃ ): 7.70(d, 2H), 7.59(d, 2H), 7.45(t, 1H), 7.36(t, 2H), 6.87(d, 2H), 3.94 (t, 2H) ), 2.56(t, 2H), 1.71~1.59(m, 4H), 1.62(t, 1H), 1.35~1.21(m, 12H).

Example 1-2: Synthesis of formula A-2 photocrosslinkable quantum dot ligand

(Formula A-2)

Add 5g (23.1 mmol) _of 4-chlorobenzophenone, 4.21g (23.1 mmol) of 3,6-dioxa-1,8-octandithiol, _6.3g (45.6 mmol) of K2CO3, and 50ml of DMF into 100ml RBF and heat at 60℃ overnight. reacted. Excess water was added, extraction was performed with MC, and the organic layer was treated with MgSO ₄ . After filtering and removing the solvent using a rotary evaporator, 50 g of methanol was added, heated to 60°C, stirred for 30 minutes, and then cooled. Filtered to obtain the product.

H NMR (δ ppm; CDCl ₃ ): 7.82(d, 2H), 7.61(d, 2H), 7.51(t, 1H), 7.43(t, 2H), 7.30(d, 2H), 3.73~3.68(m , 4H), 3.52(t, 4H), 2.94(t, 2H), 2.80(t, 2H), 1.5(t, 1H)

Example 1-3: Synthesis of formula A-3 photocrosslinkable quantum dot ligand

(Formula A-3)

20 g (91.6 mmol) of 4,4'-difluorobenzophenone, 6.52 g (91.6 mmol) of pyrrolidine, and 200 ml of DMSO were added to 500 ml RBF and heated to 60°C to react overnight. After precipitation in excess water, the filtered precipitate was recrystallized using a mixed solvent of ethanol and acetone to obtain a product in powder form. 15 g of the product, 19.2 g (93.0 mmol) of 1,10-decandithiol, 15.4 g (111.4 mmol) of K ₂ CO ₃ and 70 ml of DMF were added to a 250 ml one-neck RBF and heated at 60°C to react overnight. After precipitation in excess water, it was filtered and the precipitate was recrystallized with ethanol to obtain the product.

H NMR (δ ppm; CDCl ₃ ): 7.62(d, 2H), 7.58(d, 2H), 7.28(d, 2H), 7.02(d, 2H), 2.85(t, 4H), 2.72(t, 2H) ), 2.52(t, 2H), 1.51(t, 4H), 1.45(t, 1H), 1.32~1.21(m, 16H).

Example 1-4: Synthesis of photocrosslinkable quantum dot ligand of formula C-1

(Formula C-1)

Benzoylformic acid 5g (33.3 mmol), 10-mercaptodecanol 6.34g (33.3 mmol), para-toluenesulphonic acid 1.14g (6.66 mmol), and toluene 50 ml were added to 100ml RBF and a Dean-stark trap was installed. After heating to 120°C and reacting overnight, excess water was added and extraction was performed with EA. The organic layer was treated with MgSO ₄ , filtered under reduced pressure, the filtrate was concentrated, and then column-purified with EA:Hexane 1:4.

H NMR (δ ppm; CDCl ₃ ): 7.81(d, 2H), 7.55(t, 1H), 7.48(t, 2H), 4.05(t, 2H), 2.52(t, 2H), 1.58(t, 1H) ), 1.35~1.29(m, 18H).

Example 1-5: Synthesis of formula B-1 photocrosslinkable quantum dot ligand

(Formula B-1)

20g (81.2 mmol) of 4,4'-Difluorobenzil, 7.07g (81.2 mmol) of morpholine, and 200ml of DMSO were added to 500ml RBF and heated at 60°C to react overnight. After precipitation in excess water, the filtered precipitate was recrystallized using a mixed solvent of ethanol and acetone to obtain a product in powder form. 17.8 g of product, 15.04 g (78.2 mmol) of 1,9-nonandithiol, 12.9 g (93.8 mmol) of K ₂ CO ₃ and 70 ml of DMF were added to a 250 ml single-neck RBF and heated at 60°C to react overnight. After precipitation in excess water, it was filtered and the precipitate was recrystallized with ethanol to obtain the product.

H NMR (δ ppm; CDCl ₃ ): 7.78(d, 2H), 7.65(d, 2H), 7.37(d, 2H), 6.92(d, 2H), 3.67(t, 4H), 2.95(t, 4H) ), 2.77(t, 2H), 2.54(t, 2H), 1.54(t, 1H), 1.31~1.28(m, 14H).

Example 2-1: Ligand substitution reaction

3 mg of the benzophenone derivative represented by Chemical Formula A-1 of Example 1-1 was added to 1 mL of the quantum dot solution obtained in Preparation Example 1, and reacted for one hour while heating at 40° C. under a nitrogen atmosphere.

Next, 5 mL of acetone was added to the reaction material to precipitate the quantum dots, centrifugation was performed to separate the precipitate, and chloroform was added to disperse them. The amount of chloroform was adjusted so that the concentration of the solution was 20 mg/ml. The maximum emission wavelength of the quantum dots was 525 nm.

Example 2-2: Ligand substitution reaction

A ligand substitution reaction was performed in the same manner as in Example 2-1 using the benzophenone derivative represented by Chemical Formula A-2 in Example 1-2.

Example 2-3: Ligand substitution reaction

A ligand substitution reaction was performed in the same manner as in Example 2-1 using the benzophenone derivative represented by Chemical Formula A-3 in Example 1-3.

Example 2-4: Ligand substitution reaction

A ligand substitution reaction was performed in the same manner as in Example 2-1 using the benzophenone derivative represented by the formula C-1 of Example 1-4.

Example 2-5: Ligand substitution reaction

A ligand substitution reaction was performed in the same manner as in Example 2-1 using the benzophenone derivative represented by Chemical Formula B-1 of Example 1-5.

Experimental Example 1

A cross-sectional schematic diagram and SEM photo of the quantum dots prepared in Preparation Example 1 are shown in Figure 1.

According to Figure 1, InP (r = 1.2 nm)/ZnSe (l = 1.2 nm)/ZnS (h = 1.3 nm) quantum dots having oleic acid as a surface ligand can be confirmed.

Experimental Example 2

In Example 2-3, the change in absorbance according to the substitution % of the photocrosslinkable quantum dot ligand according to Example 1-3 was observed and is shown in Figure 2.

Referring to Figure 2, it can be seen that the higher the substitution % of the ligand, the greater the ligand absorption peak.

Experimental Example 3

In Example 2-3, TGA, NMR, and IR according to 7% of the photocrosslinkable quantum dot ligand according to Example 1-3 were observed and are shown in Figures 3 to 5, respectively.

Referring to Figures 3 to 5, it can be seen that the photo-crosslinkable quantum dot ligand is effectively bound to the quantum dot surface.

Experimental Example 4: Patterning process (coating -> curing -> development)

After substituting 7 mol% of the InP/ZnSe/ZnS quantum dots of Preparation Example 1 with the ligand represented by Chemical Formula A-3 of Example 1-3, a 20 nm thick thin film was produced.

1. The quantum dot solution prepared in Example 2-3 was spin-coated on a glass substrate at 4000 rpm for 30 seconds and then dried in a nitrogen atmosphere to prepare a quantum dot thin film.

2. Place the quantum dot thin film under the mask through the mask aligner and irradiate it with a 365 nm (1 mW/cm ² ) light source for 5 seconds.

3. An optical micrograph of the thin film pattern of quantum dots after washing with toluene is shown in Figure 6. In addition, the time resolved photoluminescence of the quantum dot thin film before and after the process was measured, and the change in optical properties of the quantum dot thin film is shown in Figure 7.

According to Figures 6 and 7, it can be confirmed that the quantum dot thin film pattern using Example 2-3 shows excellent resolution even with light irradiation for only 5 seconds, and there is no change in the optical characteristics of the quantum dot thin film before and after the process.

Claims (11)

A compound for photocrosslinkable quantum dot ligands that binds to the surface of quantum dots.
A photo-crosslinkable portion capable of self-crosslinking by light in the absence of a photoinitiator;
An anchor portion coupled to the quantum dot surface; and
It includes a body part connecting the photo-crosslinkable part and the anchor part,
Compound for photo-crosslinkable quantum dot ligand, characterized in that it is at least one selected from compound group A expressed below:
[Compound group A]
A compound for photo-crosslinkable quantum dot ligands that binds to the surface of quantum dots.
A photo-crosslinkable portion capable of self-crosslinking by light in the absence of a photoinitiator;
An anchor portion coupled to the quantum dot surface; and
It includes a body part connecting the photo-crosslinkable part and the anchor part,
Compound for photocrosslinkable quantum dot ligand, characterized in that it is at least one selected from compound group B expressed below:
[Compound group B]
A compound for photo-crosslinkable quantum dot ligands that binds to the surface of quantum dots.
A photo-crosslinkable portion capable of self-crosslinking by light in the absence of a photoinitiator;
An anchor portion coupled to the quantum dot surface; and
It includes a body part connecting the photo-crosslinkable part and the anchor part,
Compound for photocrosslinkable quantum dot ligand, characterized in that it is at least one selected from compound group C expressed below:
[Compound group C]
delete delete delete quantum dots; and
A compound for a photo-crosslinkable quantum dot ligand according to any one of claims 1 to 3 bound to the surface of the quantum dots; Photo-crosslinkable quantum dots comprising a. According to claim 7,
The quantum dots include MgO, MgS, MgSe, MgTe, CaO, CaS, CaSe, CaTe, SrO, SrS, SrSe, SrTe, BaO, BaS, BaSe, BaTE, ZnO, ZnS, ZnSe, ZnTe, CdO, CdS, CdSe, CdTe, HgO, HgS, HgSe, HgTe, Al ₂ O ₃ , Al ₂ S ₃ , Al ₂ Se ₃ , Al ₂ Te ₃ , Ga ₂ O ₃ , Ga ₂ S ₃ , Ga ₂ Se ₃ , Ga ₂ Te ₃ , In ₂ O ₃ , In ₂ S ₃ , In ₂ Se ₃ , In ₂ Te ₃ , SiO ₂ , GeO ₂ , SnO ₂ , SnS, SnSe, SnTe, PbO, PbO ₂ , PbS, PbSe, PbTe, AlN, AlP, Photo-crosslinkable quantum dots comprising a compound selected from the group consisting of AlAs, AlSb, GaN, GaP, GaAs, GaSb, InN, InP, InAs, InSb, BP, Si and Ge, and forming a core/shell structure. A photoresist composition comprising the photocrosslinkable quantum dots according to claim 7 and a solvent. The photoresist composition of claim 9, wherein the composition contains more than 0 to 0.1% by weight or less of a photoinitiator based on the total weight of the composition. An electronic device manufactured using the photoresist composition containing photocrosslinkable quantum dots according to claim 9.