KR20240156187A - Millbase, negative type photosensitive resin composition comprising same, black bank, organic emitting device and preparation method for millbase - Google Patents

Abstract

The present specification relates to a modified millbase, a negative photosensitive resin composition containing the same, a black bank, an organic light-emitting element, and a method for producing the millbase. The millbase of the present invention can improve light-shielding characteristics, significantly reduce residue, improve dark spot defects, and significantly improve surface roughness (Ra) characteristics based on a black bank after curing.

Description

Millbase, negative type photosensitive resin composition containing same, black bank, organic light-emitting device and preparation method for millbase {MILLBASE, NEGATIVE TYPE PHOTOSENSITIVE RESIN COMPOSITION COMPRISING SAME, BLACK BANK, ORGANIC EMITTING DEVICE AND PREPARATION METHOD FOR MILLBASE}

The present specification relates to a millbase, a negative photosensitive resin composition including the same, a black bank, an organic light-emitting element, and a method for producing the millbase.

In an organic light emitting diode (OLED), a bank serves to define the shape of a pixel by forming a polyimide insulating layer in all areas except for the area where an organic light emitting material is deposited to act as a pixel, and enables each pixel to be driven electrically independently. Positive type photosensitive polyimide (PSPI) is mainly used as a material for forming the bank.

In the case of conventional polyimide-based transparent banks, there is a limit to preventing reflection due to external light, and there is a characteristic that the image quality deteriorates due to light leakage phenomenon occurring due to reflection by metal wiring. In addition, when a polarizing plate is used to alleviate the above external light reflection problem, the transmittance is significantly reduced, so that high voltage driving is required to obtain higher transmittance, which causes a problem of shortening the lifespan of the organic light-emitting element.

Accordingly, in the field of technology, a colored colorant (containing color pigments) with light-blocking properties is used to improve visibility by alleviating the problem of external light reflection in organic light-emitting devices.

However, when the colorant of the above-mentioned colored pigment is included in an organic light-emitting device, residue remains, which may adversely affect the lifespan of the organic light-emitting device or cause dark spot defects. Therefore, additional research on the colorant is necessary.

The present application seeks to provide a millbase capable of improving the above problems and a method for producing the same, a negative photosensitive resin composition including the millbase, a black bank, an organic light-emitting element, and a method for producing the millbase.

The inventors of the present invention have found that by modifying the composition of a pigment having light-blocking properties and the average particle size, the occurrence of residues in organic light-emitting devices can be prevented and dark spot defects can be prevented.

Accordingly, one embodiment of the present specification provides a mill base comprising a colorant and a dispersant, the average particle size being 70 nm or less, and the colorant having at least one lactam-based black pigment.

Another embodiment of the present specification provides a negative photosensitive resin composition comprising the mill base; a binder resin; a multifunctional monomer; and a photoinitiator.

Another embodiment of the present specification provides a black bank comprising the photosensitive resin composition or a cured product thereof.

Another embodiment of the present disclosure provides an organic light-emitting device comprising the black bank.

Another embodiment of the present specification provides a method for manufacturing the mill base.

The millbase according to the present specification can improve light-blocking properties by ensuring safety and/or stability, while significantly reducing residue and improving dark spot defects in organic light-emitting devices.

In addition, the mill base according to the present specification can significantly improve the surface roughness based on the black bank after curing.

Figure 1 shows SEM and microscope photographs of Comparative Examples 1 and 6 and Example 1 from left to right.
Figure 2 is an application structure of a transparent bank manufactured with a positive photosensitive resin composition of the prior art.
FIG. 3 is an application structure of a black bank manufactured with a negative photosensitive resin composition having a lactam-based black pigment according to one embodiment of the present specification.

Below, the present specification is described in more detail.

When it is said in this specification that an element is located "on" another element, this includes not only cases where an element is in contact with another element, but also cases where another element exists between the two elements.

When it is said in this specification that a part "includes" a certain component, this does not exclude other components, but rather may include other components, unless otherwise specifically stated.

<Millbase>

One embodiment of the present specification provides a millbase comprising a colorant and a dispersant, the average particle size being 70 nm or less, and the colorant having at least one lactam-based black pigment.

The mill base according to the above embodiment can improve the light-blocking characteristics, and at the same time, significantly reduce residue on the organic light-emitting element and improve dark spot defects. In addition, the mill base according to the present specification can significantly improve the surface roughness (Ra) characteristics based on the black bank after curing.

Referring to Figure 1, the image on the far right, which corresponds to the use of a millbase having a lactam-based black pigment and an average particle size controlled to 70 nm or less, shows the characteristics of no residue and improved surface roughness. On the other hand, when the average particle size is not controlled to 70 nm or less or does not include a lactam-based black pigment, it can be confirmed that there is residue and the surface roughness is poor, as shown in the two images on the left.

In this specification, millbase is used interchangeably with pigment dispersion, pigment mixture, pigment dispersion composition, etc., and means a type of dispersion containing pigment, a liquid that helps to finely disperse pigment particles and maintain a stable dispersion state.

In this specification, the average particle size of the mill base is measured by dynamic light scattering after diluting the mill base to a certain concentration. The measurement method may use a method and device known in the art, and ZETASIZER Nano ZS90 (Malvern) may be used.

In this specification, the colorant is characterized by having at least one lactam-based black pigment. Accordingly, the lactam-based black pigment has a lower permittivity or higher resistance than conventional carbon black, and thus can be more suitably used as an insulating film such as a black bank.

In this specification, the dispersant is a material that helps to efficiently disperse the colorant on the mill base, and includes, for example, Disperbyk-2001 (BYK), but is not particularly limited as long as it corresponds to a dispersant known in the art.

In another embodiment of the present specification, the average particle size of the mill base may be 30 nm or less.

In another embodiment of the present specification, the average particle size of the mill base may be 30 nm or more and 70 nm or less.

In other embodiments of the present specification, the average particle size of the mill base may be 30 nm or more, 35 nm or more, 40 nm or more, or 50 nm or more, or 70 nm or less, or 65 nm or less.

In one embodiment of the present specification, the average particle size of the mill base may be 40 nm or more and 65 nm or less.

When within the above average particle size range, residue can be prevented or dispersion stability can be improved.

In one embodiment of the present specification, the colorant may further include a color pigment other than a lactam black pigment. In the present specification, the color pigment may be, for example, a red pigment, a yellow pigment, a green pigment, a blue pigment, a purple pigment, etc., and may be composed of one color pigment or may be a mixture of two or more color pigments.

In one embodiment of the present specification, the colorant may further include at least one color pigment selected from the group consisting of a yellow pigment, a green pigment, a blue pigment, and a purple pigment. In other words, the colorant may be a black pigment consisting solely of one type of lactam-based black pigment, a mixture (or codispersion) of two or more types of lactam-based black pigments, or a mixture (or codispersion) of one or more types of lactam-based black pigments and one or more types of color pigments.

In other embodiments of the present specification, the dispersant may be a single substance or a mixture of two or more materials.

In one embodiment of the present specification, the mill base may further include at least one of a dispersion binder, a dispersing agent, and a solvent.

In this specification, the dispersion binder, dispersion agent, and solvent may be any of those known in the art.

In another embodiment of the present specification, the dispersion binder may be a single material or a mixture of two or more materials. Preferably, the dispersion binder may use a (meth)acrylic binder.

In another embodiment of the present specification, the dispersing agent may be a single substance or a mixture of two or more materials.

In other embodiments of the present specification, the solvent may be a single substance or a mixture of two or more materials.

In this specification, the dispersing agent is a material that helps the dispersing agent to function so as to reduce the dispersion time for the mill base and efficiently maintain the viscosity, and includes, for example, Solsperse 22000 (Lubrizol), but is not particularly limited as long as it corresponds to a dispersing agent known in the art.

In this specification, the solvent is used as a solvent for the mill base, and the solvent for the mill base includes, for example, propylene glycol monomethyl ether acetate (PGMEA), but is not particularly limited as long as it is a solvent known in the art.

In one embodiment of the present specification, based on 100 parts by weight of the mill base, it may include 10 to 50 parts by weight of a colorant, 1 to 30 parts by weight of a dispersant, 1 to 30 parts by weight of a dispersion binder, 0.1 to 5 parts by weight of a dispersing aid, and 10 to 90 parts by weight of a solvent.

Within the above range, it can exhibit excellent viscosity characteristics and excellent viscosity retention. Accordingly, the viscosity of the mill base can be more than 0 cP, 1 cP or more, or 3 cP or more, 15 cP or less, 13 cP or less, or 10 cP or less, and the viscosity retention can be 95% or more, but is not limited thereto.

In one embodiment of the present specification, the lactam black pigment may include a compound represented by the following chemical formula 1.

[Chemical Formula 1]

In the above chemical formula 1,

Ra is H (hydrogen) or an alkyl group,

R ₄ , R ₅ , R ₆ and R ₇ are the same or different and are each independently H, halogen, -COOR ₈ , -CONR ₈ R ₉ , -OR ₈ , -OOCR ₈ , -OOCNR ₈ R ₉ , OH, CN, NO ₂ , -NR ₈ R ₉ , -NR ₈ COR ₉ , -N=CR ₈ R ₉ , -SR ₈ , -SOR ₈ , -SO _x R ₈ (x=1~3) or -SO ₂ NR ₈ R ₉ , or R ₄ and R ₅ , R ₅ and R ₆ , or R ₆ and R ₇ are directly bonded or bonded to each other through an O, S or NR ₈ bridge to form a ring,

Rb is a single or multiple ring group containing one of N, O, S, CO, and COO,

R ₈ and R ₉ are the same as or different from each other, and are each independently H, C ₁ to C ₁₂ alkyl, C ₃ to C ₁₂ cycloalkyl, C ₂ to C ₁₂ alkenyl, C ₃ to C ₁₂ cycloalkenyl or C ₂ to C ₁₂ alkynyl, and at least one of -CH ₂ -, -CH= and =C= constituting them is substituted with -COO-, -O-, -CONR ₁₀ -, =N-, -NR ₁₀ -, -S- or -CO-, or at least one of the hydrogens bonded to carbon is halogen, -COOR ₁₀ , -CONR ₁₀ R ₁₁ , -OR ₁₀ , -OOCR ₁₀ , -OOCNR ₁₀ R ₁₁ , OH, CN, NO ₂ , -NR ₁₀ COR ₁₁ , -N=CR ₁₀ R ₁₁ , -SR ₁₀ , -SOR ₁₀ , -SOxR ₁₀ (x=1~3), -SO ₂ NR ₁₀ R ₁₀ , or -NR ₁₀ R ₁₁ , wherein R ₁₀ and R ₁₁ are each independently a C ₂ to C ₆ alkyl group, or a group containing O, S or NH.

In another embodiment of the present specification, Rb of the chemical formula 1 is , where Rc and Rd are the same or different, and can each independently be H, CH ₃ , CF ₃ , F, or Cl.

In another embodiment of the present specification, the chemical formula 1 can be represented by the following compound.

(S0100CF, BASF)

<Negative photosensitive resin composition>

One embodiment of the present specification provides a negative photosensitive resin composition comprising: any one of the above-described millbases; an alkali-soluble resin; a multifunctional monomer; and a photoinitiator.

The negative photosensitive resin composition of the above embodiment can not only have the advantages of the mill base itself as described above, but also provide developability to an alkaline developer and obtain heat resistance characteristics.

In one embodiment of the present specification, the alkali-soluble resin can be represented by the following chemical formula 2.

[Chemical formula 2]

In the above chemical formula 2,

* indicates the binding position,

X ₁ and X ₂ are the same as or different from each other, and each independently represents one selected from the group consisting of alkylene having 1 to 60 carbon atoms, divalent ethylene oxide, and divalent propylene oxide,

Y is selected from the group consisting of divalent cyclohexene, divalent cyclohexyne, phenylene group and alkyl group having 3 to 10 carbon atoms,

n is a real number between 2 and 50.

For example, in the chemical formula 2, X1 and X2 may be methylene groups, and Y may be divalent cyclohexene.

The negative photosensitive resin composition of the above embodiment includes a binder resin represented by the chemical formula 2, thereby providing a negative photosensitive resin composition having excellent thermal stability and improved mechanical properties due to alkaline solubility.

In the present specification, the polyfunctional monomer may be a polyfunctional monomer having an ethylenically unsaturated double bond.

Examples of the polyfunctional monomer having the above-mentioned ethylenically unsaturated double bond include compounds having at least one or two addition-polymerizable unsaturated groups in the molecule and having a boiling point of 100°C or higher, or polyfunctional monomers introducing caprolactone.

Non-limiting examples of compounds having at least one or more addition-polymerizable unsaturated groups among the above molecules and having a boiling point of 100° C. or higher include polyfunctional monomers such as polyethylene glycol mono(meth)acrylate, polypropylene glycol mono(meth)acrylate, or phenoxyethyl(meth)acrylate; polyfunctional monomers such as polyethylene glycol(meth)acrylate, polypropylene glycol(meth)acrylate, trimethylol ethane triacrylate, trimethylol propane triacrylate, neopentyl glycol(meth)acrylate, pentaerythritol tetraacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, or dipentaerythritol hexaacrylate.

Non-limiting examples of polyfunctional monomers introducing the above caprolactone include cases where caprolactone is introduced into dipentaerythritol, cases where caprolactone is introduced into tetrahydrofuryl acrylate, cases where caprolactone is introduced into neopentyl glycol hydroxypivalate, cases where caprolactone is introduced into bisphenol A derivatives, and cases where caprolactone is introduced into polyfunctional monomers of the urethane series.

Specifically, there are KAYARAD DPCA-20, 30, 60, 120, etc. which introduce caprolactone into dipentaerythritol, and FA-2D, FA1DT, FA-3, etc., and KAYARAD TC-110S which introduces caprolactone into tetrahydrofuryl acrylate, or KAYARAD HX-220, KAYARAD HK-620 which introduces caprolactone into neopentyl glycol hydroxypivalate, etc. can be used.

There are also epoxy acrylates and novolac-epoxy acrylates of other bisphenol A derivatives in which caprolactone is introduced, and there are also polyfunctional acrylates of the urethane series such as U-324A, U15HA, and U-4HA in which caprolactone is introduced.

The above polyfunctional monomer having an ethylenically unsaturated double bond may be used alone or in combination of two or more.

It is preferable that the polyfunctional monomer having the above-mentioned ethylenically unsaturated double bond is contained in an amount of about 1 to 30 wt% based on the total weight of the resin composition. When the content is 1 wt% or more, it is advantageous for photosensitivity or the strength of the insulating film, and when it is 30 wt% or less, it can prevent the adhesiveness of the coating from becoming excessive, and prevent the strength of the insulating film from decreasing and the pattern from disappearing during development.

As an example, the amount of the alkali-soluble resin binder and the polyfunctional monomer having an ethylenically unsaturated double bond is preferably 1:0.3 to 1:1 in weight ratio, and more preferably 1:0.4 to 1:08. When manufactured at the above ratio, when a pattern is formed by development after photopolymerization of the resin composition according to the embodiments of the present specification using a predetermined pattern mask, the taper angle of the pattern film after development can have a gentle angle of 35 degrees or less. When the taper angle is gentle in this way, even if an electrode is formed on the pattern, the possibility of a short circuit occurring in the electrode is reduced.

In this specification, the photoinitiator is a material that generates radicals by light, and it is preferable to use one or more compounds selected from the group consisting of acetophenone compounds, biimidazole compounds, triazine compounds, and oxime compounds.

The acetophenone compounds that can be used as the photoinitiator include 2-hydroxy-2-methyl-1-phenylpropan-1-one, 1-(4-isopropylphenyl)-2-hydroxy-2-methylpropan-1-one, 4-(2-hydroxyethoxy)-phenyl-(2-hydroxy-2-propyl)ketone, 1-hydroxycyclohexylphenyl ketone, benzoin methyl ether, benzoin ethyl ether, benzoin isobutyl ether, benzoin butyl ether, 2,2-dimethoxy-2-phenylacetophenone, 2-methyl-(4-methylthio)phenyl-2-morpholino-1-propan-1-one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one, Those selected from the group consisting of 2-(4-bromo-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butan-1-one and 2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one can be used.

As the biimidazole compound, one selected from the group consisting of 2,2-bis(2-chlorophenyl)-4,4',5,5'-tetraphenyl biimidazole, 2,2'-bis(o-chlorophenyl)-4,4',5,5'-tetrakis(3,4,5-trimethoxyphenyl)- 1,2'-biimidazole, 2,2'-bis(2,3-dichlorophenyl)-4,4',5,5'-tetraphenyl biimidazole, and 2,2'-bis(o-chlorophenyl)-4,4,5,5'-tetraphenyl-1,2'-biimidazole can be used.

Triazine compounds include 3-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propionic acid, 1,1,1,3,3,3-hexafluoroisopropyl-3-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propionate, ethyl-2-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}acetate, 2-epoxyethyl-2-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}acetate, and cyclohexyl-2-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}acetate. A compound selected from the group consisting of benzyl-2-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}acetate, 3-{chloro-4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propionic acid, 3-{4-[2,4-bis(trichloromethyl)-s-triazin-6-yl]phenylthio}propionamide, 2,4-bis(trichloromethyl)-6-p-methoxystyryl-s-triazine, 2,4-bis(trichloromethyl)-6-(1-p-dimethylaminophenyl)-1,3,-butadienyl-s-triazine, and 2-trichloromethyl-4-amino-6-p-methoxystyryl-s-triazine can be used.

Examples of the oxime compounds include 1,2-octadio-1-(4-phenylthio)phenyl-2-(o-benzoyloxime) (Ciba-Geigy, CGI 124), ethanone-1-(9-ethyl)-6-(2-methylbenzoyl-3-yl)-1-(o-acetyloxime) (CGI 242), oxime OX-03 (Ciba-Geigy), NCI-831 (Adeka), PI-102 (LG Chemical), PBG 304, PBG 305, PBG 3057 (Tronni), etc. The photoinitiator is preferably included in an amount of 0.5 to 10 wt% based on the total weight of the resin composition. More preferably, it is good to use 10 to 300 parts by weight (based on the total amount of photoinitiator used) based on 100 parts by weight of the polyfunctional monomer having the ethylenically unsaturated double bond, and in particular, 0.5 to 5 wt% of the acetophenone-based compound can be used based on the total weight of the resin composition, or 0.01 to 3 wt% of the oxime-based initiator can be mixed and used.

The above photoinitiator may additionally include 0.01 to 5 wt% of a photocrosslinking initiator that promotes the generation of radicals as an auxiliary component, or 0.01 to 5 wt% of a curing accelerator that promotes curing, based on the total weight of the resin composition.

The above-mentioned photocrosslinking sensitizers include benzophenone compounds such as benzophenone, 4,4-bis(dimethylamino)benzophenone, 4,4-bis(diethylamino)benzophenone, 2,4,6-trimethylaminobenzophenone, methyl-o-benzoylbenzoate, 3,3-dimethyl-4-methoxybenzophenone, and 3,3,4,4-tetra(t-butylperoxycarbonyl)benzophenone; fluorenone compounds such as 9-fluorenone, 2-chloro-9-fluorenone, and 2-methyl-9-fluorenone; thioxanthone compounds such as thioxanthone, 2,4-diethyl thioxanthone, 2-chloro thioxanthone, 1-chloro-4-propyloxy thioxanthone, isopropylthioxanthone, and diisopropylthioxanthone. Xanthone compounds, such as xanthone, 2-methylxanthone; anthraquinone compounds, such as anthraquinone, 2-methyl anthraquinone, 2-ethyl anthraquinone, t-butyl anthraquinone, and 2,6-dichloro-9,10-anthraquinone; acridine compounds, such as 9-phenylacridine, 1,7-bis(9-acridinyl)heptane, 1,5-bis(9-acridinylpentane), and 1,3-bis(9-acridinyl)propane; dicarbonyl compounds, such as benzyl, 1,7,7-trimethyl-bicyclo[2,2,1]heptane-2,3-dione, and 9,10-phenanthrenequinone; Phosphine oxide compounds such as 2,4,6-trimethylbenzoyl diphenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethylpentyl phosphine oxide; benzophenone compounds such as methyl-4-(dimethylamino)benzoate, ethyl-4-(dimethylamino)benzoate, and 2-n-butoxyethyl-4-(dimethylamino)benzoate; Amino synergists such as 2,5-bis(4-diethylaminobenzal)cyclopentanone, 2,6-bis(4-diethylaminobenzal)cyclohexanone, and 2,6-bis(4-diethylaminobenzal)-4-methyl-cyclopentanone; Coumarin compounds such as 3,3-carbonylvinyl-7-(diethylamino)coumarin, 3-(2-benzothiazolyl)-7-(diethylamino)coumarin, 3-benzoyl-7-(diethylamino)coumarin, 3-benzoyl-7-methoxy-coumarin, 10,10-carbonylbis[1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H,11H-C1]-benzopyrano[6,7,8-ij]-quinolizin-11-one; chalcone compounds such as 4-diethylamino chalcone, 4-azidebenzalacetophenone; 2-benzoylmethylene, or 3-methyl-b-naphthothiazoline can be used.

In addition, as the curing accelerator, 2-mercaptobenzimidazole, 2-mercaptobenzothiazole, 2-mercaptobenzoxazole, 2,5-dimercapto-1,3,4-thiadiazole, 2-mercapto-4,6-dimethylaminopyridine, pentaerythritol-tetrakis(3-mercaptopropionate), pentaerythritol-tris(3-mercaptopropionate), pentaerythritol-tetrakis(2-mercaptoacetate), pentaerythritol-tris(2-mercaptoacetate), trimethylolpropane-tris(2-mercaptoacetate), or trimethylolpropane-tris(3-mercaptopropionate) can be used.

In the present specification, the solvent is, as a solvent for a negative type photosensitive resin composition, when considering solubility, pigment dispersibility, coating property, etc., propylene glycol monomethyl ether, ethylene glycol monomethyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, diethylene glycol dimethyl ether, cyclohexanone, 2-heptanone, 3-heptanone, 2-hydroxyethylpropionate, 3-methyl-3-methoxybutylpropionate, ethyl-3-methoxypropionate, methyl-3-ethoxypropionate, ethyl-3-ethoxypropionate, butyl acetate, amyl permate, isoamyl acetate, isobutyl acetate, butyl propionate, isopropyl butyrate, ethyl butyrate, butyl butyrate, ethyl pyruvate, or γ-Butyrol acetate, etc. can be used. The above solvents can be used alone or in combination of two or more types.

The resin composition according to the above-described embodiment may additionally contain additives as long as they do not adversely affect the purpose of the present invention.

In another embodiment of the present specification, the additive may be at least one selected from an adhesive agent, an antioxidant, an ultraviolet absorber, an antifoaming agent, and a surfactant.

In this specification, the total content of the additive may be 0.01 part by weight or more and 1 part by weight or less with respect to 100 parts by weight of the photosensitive resin composition.

If the above additive is included in an amount of less than 0.01 part by weight, the effect of the additive is minimal, and if it is included in an amount exceeding 1 part by weight, the hydrophilicity of the surface is lowered, which may inhibit the penetration of the developer and thus inhibit the developability.

In this specification, the surfactant is not particularly limited, and can be used without limitation as long as it is applicable to the relevant technical field.

In this specification, the surfactant may be, but is not limited to, a fluorine-based surfactant or a silicone-based surfactant.

In the present specification, the surfactant is a silicone-based surfactant or a fluorine-based surfactant, and specifically, the silicone-based surfactant is BYK-077, BYK-085, BYK-300, BYK-301, BYK-302, BYK-306, BYK-307, BYK-310, BYK-320, BYK-322, BYK-323, BYK-325, BYK-330, BYK-331, BYK-333, BYK-335, BYK-341, BYK-344, BYK-345, BYK-346, BYK-348, BYK-354, BYK-355, BYK-356, BYK-358, BYK-361, BYK-370, BYK-371, BYK-375, BYK-380, BYK-390, etc. can be used, and as fluorinated surfactants, DIC (DaiNippon Ink & Chemicals) F-114, F-177, F-410, F-411, F-450, F-493, F-494, F-443, F-444, F-445, F-446, F-470, F-471, F-472SF, F-474, F-475, F-477, F-478, F-479, F-480SF, F-482, F-483, F-484, F-486, F-487, F-172D, R-40, R-41, The following may be used, but are not limited to: MCF-350SF, TF-1025SF, TF-1117SF, TF-1026SF, TF-1128, TF-1127, TF-1129, TF-1126, TF-1130, TF-1116SF, TF-1131, TF1132, TF1027SF, TF-1441, TF-1442.

When a surfactant is included in the negative type photosensitive resin composition, the surfactant may be included in an amount of 0.01 part by weight to 1 part by weight, 0.01 part by weight to 0.5 part by weight, or 0.01 part by weight to 0.1 part by weight, based on 100 parts by weight of the total negative type photosensitive resin composition.

In another embodiment of the present specification, the adhesive agent may be a silane coupling agent, an imidazole-based agent, a triazole-based agent, or a thiol-based agent.

In another embodiment of the present specification, the silane coupling agent means a compound containing a hydrolyzable silyl group or silanol group, which can increase the adhesion between a specific surface of a cured film and a substrate, thereby increasing heat resistance and chemical resistance. As examples of the silane coupling agent, at least one of octyltrimethoxy silane, dodecyltrimethoxy silane, octadecyltrimethoxy silane, and the like can be selected and used, but is not limited thereto.

In another embodiment of the present specification, the imidazole-based adhesive agent includes, but is not limited to, 1-methyl benzimidazole.

In another embodiment of the present specification, examples of the triazole-based adhesive agent include, but are not limited to, TT-LX, BT-LX (Johoku chemical), Irgamet 42 (Ciba), 1-methyl-1-H-benzotriazole, 3-mercapto-1,2,4-triazole, benzotriazole-5-carboxylic acid, N,N-dimethyl benzo triazole methan amine, and the like.

In another embodiment of the present specification, the thiol-based adhesive agent includes, but is not limited to, Bismuthiol.

When the adhesive agent is included in the negative type photosensitive resin composition, the adhesive agent may be included in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the total negative type photosensitive resin composition.

In one embodiment of the present specification, the antioxidant may play a role in preventing a chain reaction in which radicals are generated during polymer film formation. At this time, the antioxidant may include a phenol-based antioxidant, and 2,2-thiobis(4-methyl-6-t-butylphenol), 2,6-g,t-butylphenol, or the like, which are antioxidants commonly used in the art, may be used.

The above ultraviolet absorbent may be, but is not limited to, 2-(3-t-butyl-5-methyl-2-hydroxyphenyl)-5-chloro-benzotriazole, or alkoxy benzophenone.

When an antioxidant is included in the negative type photosensitive resin composition, the antioxidant may be included in an amount of 0.01 to 1 part by weight based on 100 parts by weight of the entire negative type photosensitive resin composition.

In another embodiment of the present specification, the antifoaming agent is an additive that suppresses bubble formation, and when included in the negative photosensitive resin composition of the present invention, it has the effect of removing bubbles in the liquid phase to improve the coatability and removing bubbles that may exist in the film after coating.

Examples of the above-mentioned foaming agents include, but are not limited to, BYK-141 and BYK-392 from BYK-Chemie.

In another embodiment of the present specification, the weight average molecular weight of the alkali-soluble resin may be 10,000 g/mol or more and 100,000 g/mol or less.

When the weight average molecular weight of the alkali-soluble resin satisfies the above-mentioned range, the photosensitive resin composition containing it has excellent physical and chemical properties, appropriate viscosity, and excellent adhesion to a substrate.

In this specification, the weight average molecular weight refers to one of the average molecular weights in which the molecular weight is not uniform and the molecular weight of a certain polymer material is used as a standard, and is a value obtained by averaging the molecular weights of component molecular species of a polymer compound having a molecular weight distribution by weight fraction. The weight average molecular weight can be measured by a gel permeation chromatography (GPC) method.

In one embodiment of the present specification, the negative photosensitive resin composition may include, based on 100 parts by weight of solid content, 1 part by weight or more and 50 parts by weight or less of a millbase, 10 parts by weight or more and 70 parts by weight or less of a binder resin, 10 parts by weight or more and 50 parts by weight or less of a multifunctional monomer, and 1 part by weight or more and 10 parts by weight or less of a photoinitiator.

The negative photosensitive resin of the above embodiment can have improved mechanical properties (e.g., control of adhesion of a coating film, control of strength of an insulating film (black bank), and prevention of pattern loss during development) by satisfying the content range of each component described above.

<Black Bank>

One embodiment of the present specification provides a black bank comprising a photosensitive resin composition or a cured product thereof.

In this specification, the black bank may be used interchangeably with the insulating film.

The above black bank or insulating film may contain the negative photosensitive resin composition as it is.

The above black bank or insulating film may include a cured product of the negative type photosensitive resin composition.

In one embodiment of the present specification, the surface roughness (Ra) value may be 2 nm or less.

In one embodiment of the present specification, the surface roughness (Ra) value may be greater than 0 nm and less than or equal to 2 nm.

In this specification, the surface roughness (Ra) is measured based on a film that has been cured after pattern formation.

In this specification, the surface roughness of a cured film, such as a cured film, a black bank, or an insulating film, can be evaluated.

In one embodiment of the present specification, the optical density (OD) may be 0.3 /㎛ or more and 4.0 /㎛ or less.

In one embodiment of the present specification, the optical density may be 0.4 /㎛ or more, 0.5 /㎛ or more, or 0.6 /㎛ or more, or 3.9 /㎛ or less, 3.8 /㎛ or less, or 3.7 /㎛ or less.

When it falls within the above range, it is effective in reflecting external light and can have low reflectivity and high color reproducibility characteristics.

In this specification, the optical density can be measured based on a film (e.g., a cured film) that has been cured after pattern formation.

In this specification, the optical density was measured using an OD meter from iCFilm (Grettagmacbeth) on a cured black bank film.

The above black bank or insulating film may include a support or substrate.

The support or substrate is not particularly limited, and a known one in the art can be used. For example, a substrate for electronic components or a substrate having a predetermined wiring pattern formed thereon can be exemplified. As the substrate, for example, a metal substrate such as silicon, silicon nitride, titanium, tantalum, palladium, titanium tungsten, copper, chromium, iron, aluminum, gold, nickel, or a glass substrate can be exemplified. As a material for the wiring pattern, for example, copper, solder, chromium, aluminum, nickel, gold, or the like can be used, but is not limited thereto. Preferably, the support or substrate can be a silicon wafer.

The above coating method is not particularly limited, but spraying, roll coating, spin coating, etc. can be used, and generally, spin coating is widely used. In addition, after forming the coating film, some of the residual solvent can be removed under reduced pressure, depending on the case.

In the present specification, the thickness of the black bank or insulating film may be 1 ㎛ to 10 ㎛. When the thickness range of the insulating film is satisfied, a black bank or insulating film having excellent chemical resistance and mechanical properties aimed at in the present specification can be obtained. The thickness can be measured using a scanning electron microscope (SEM).

<small>

One embodiment of the present specification provides an organic light-emitting device including the black bank.

One embodiment of the present specification provides a semiconductor device including the black bank.

The above organic light-emitting device can be manufactured by further including various components commonly used in the art in addition to the black bank.

For example, it can be manufactured as follows. A transparent electrode such as ITO (Indium Tin Oxide) is deposited by sputtering on a transparent substrate such as glass, and a patterned transparent electrode is formed through processes such as PR coating, exposure, development, etching, and PR removal, and then a black bank is formed using the resin composition described above. For example, the resin composition described above can be coated on a substrate on which an electrode is formed to form a film, and after exposure using a photomask or the like and radiation including ultraviolet rays, the exposed substrate can be developed, washed, and dried to form a pattern. Subsequently, a partition wall for distinguishing each pixel can be formed on the formed black bank.

Thereafter, an organic thin film is deposited as a single layer or multiple layers. The organic thin film includes a light-emitting layer, and may further include other charge transport or charge blocking layers, such as an electron injection layer, an electron transport layer, a hole blocking layer, a hole transport layer, a hole injection layer, and/or an electron blocking layer, as needed. Then, a metal electrode layer is deposited. Next, the hollow SUS can and the substrate are sealed (sealed) with a sealing material (sealing agent) such as epoxy resin, and then assembled into a module to manufacture an organic light-emitting element.

Figure 2 shows an application structure of a transparent bank manufactured with a positive photosensitive resin composition of the prior art, which is implemented with a positive photosensitive polyimide composition without light-shielding properties.

FIG. 3 is an application structure of a black bank manufactured with a negative photosensitive resin composition having a lactam-based black pigment according to one embodiment of the present specification, wherein the external light reflection is effectively improved by using a lactam-based black pigment having light-blocking properties, and the color reproducibility can be improved by lowering the reflectance.

<Method for manufacturing wheat base>

One embodiment of the present specification provides a method for producing a mill base, comprising the steps of: mixing a colorant and a dispersant to provide a mixture; milling the mixture with first beads of 0.5 mm or more and 1.2 mm or less to perform a first dispersion; and milling the first dispersion with second beads of 0.05 mm or more and 0.3 mm or less to produce a mill base, wherein the mill base is as described above.

The intensity and time of the first and second dispersions can be appropriately changed within the range of obtaining the average particle size targeted by the person skilled in the art.

By the method for manufacturing a mill base according to the above-described embodiment, the average particle size of the mill base can be efficiently controlled to 70 nm or less while suppressing the aggregation of one or more lactam-based black pigments contained in the colorant.

In some cases, the colorant may have a color pigment other than a lactam black pigment (selected from the group consisting of a red pigment, a yellow pigment, a green pigment, a blue pigment and a purple pigment).

Hereinafter, in order to specifically explain this specification, examples will be given and described in detail. However, the examples according to this specification may be modified in various different forms, and the scope of this specification is not construed as being limited to the examples described below. The examples of this specification are provided to more completely explain this specification to a person having average knowledge in the art.

<Manufacturing Example>

The mill base (pigment dispersion) of the present invention was prepared as follows.

Manufacturing example 1.

A mixture was prepared by mixing 80 parts by weight of a lactam black pigment (BASF S0100CF), 80 parts by weight of an acrylic binder (number average molecular weight 13,000 g/mol, acid value 100 KOHmg/g) containing benzyl (meth)acrylate, N-phenylmaleimide, styrene, and (meth)acryl in a molar ratio of 55:9:11:25 as a dispersion binder, 100 parts by weight of a dispersant (BYK Disperbyk-2001), 1 part by weight of a dispersing aid (Solsperse 22000), and 150 parts by weight of a solvent (propylene glycol monomethyl ether acetate (PGMEA)) at 1000 rpm for 60 minutes.

The first dispersion was obtained by milling the above mixture using a first bead having a size of one of 0.5 to 1.2 mm.

Thereafter, a milling process was performed for the primary dispersion using second beads having a size of 0.05 mm to 0.3 mm to obtain a mill base. At this time, the intensity and time of the secondary dispersion were adjusted to produce a corresponding mill base having an average particle size of about 55 nm.

Manufacturing examples 2 and 3.

As shown in Table 1 below, the same method as Manufacturing Example 1 was performed, except that the intensity and time of the secondary dispersion were adjusted to manufacture mill bases having average particle sizes of approximately 58 nm and 65 nm, respectively.

Manufacturing example 4.

The same method as Manufacturing Example 1 was performed, except that a mill base having an average particle size of 58 nm was produced using 56 parts by weight of a black lactam pigment (BASF S0100CF), 24 parts by weight of a blue pigment (trade name: 15:6), 80 parts by weight of a dispersion binder, 100 parts by weight of a dispersant (BYK Disperbyk-2001), 1 part by weight of a dispersing aid (Solsperse 22000), and 150 parts by weight of a solvent (propylene glycol monomethyl ether acetate (PGMEA)).

Manufacturing example 5.

The same method as Manufacturing Example 1 was performed, except that a mill base having an average particle size of 53 nm was manufactured using 24 parts by weight of a lactam-based black pigment (BASF S0100CF), 48 parts by weight of a blue pigment (trade name: 15:6), and 8 parts by weight of a purple pigment (V23), as shown in Table 1 below.

Comparative manufacturing examples 1 to 6.

As shown in Table 1 below, the same method as Manufacturing Example 1 was performed, except that the intensity and time of the secondary dispersion were adjusted to manufacture a mill base having an average particle size exceeding 70 nm.

Comparative manufacturing example 7.

As shown in Table 1 below, the same method as Manufacturing Example 1 was performed except that 80 parts by weight of carbon black pigment was used instead of the lactam black pigment.

<Synthesis Example> Synthesis of binder resin

Synthesis Example: Synthesis of binder resin

122 g of 9,9-bisphenol fluorenediglycidyl ether and 45 g of 4-cyclohexyne-1,2-dicarboxylic acid were stirred with 150 g of propylene glycol monomethyl ether acetate (PGMEA). The reactor was heated to 110°C while supplying oxygen into the reactor.

After 10 hours, the reaction was terminated and 200 g of reaction solvent (PGMEA) was added to obtain a binder resin. (Solid content: 29.19%, acid value: 25, molecular weight: 13000 g/mol)

<Example> Preparation of negative photosensitive resin composition

25.8 parts by weight of the mill bases of Manufacturing Examples 1 to 5 and Comparative Manufacturing Examples 1 to 7, 19.6 parts by weight of the binder resin of the above-mentioned synthesis example, 10 parts by weight of a polyfunctional monomer (DPHA, Dipentaerithritol penta-/hexa-acrylate, Sigma-Aldrich), 0.4 parts by weight of a photoinitiator (OXE-02, BASF), 0.1 parts by weight of a surfactant (BYK-307, BYK Chemie), and 44.1 parts by weight of a solvent (PGMEA, propylene glycol monomethyl ether acetate) were placed in a reactor, and stirred for 4 hours to produce negative-type photosensitive resin compositions of Examples 1 to 5 and Comparative Examples 1 to 7.

<Experimental example>

1) Preparation of samples

The negative photosensitive resin compositions of Examples 1 to 5 and Comparative Examples 1 to 7 were spin-coated on glass, and heat-treated at about 100° C. for 2 minutes to form a film having a thickness of about 1.5 μm. Then, after cooling to room temperature, the film was exposed using a photomask at an energy of 80 mJ/cm2 based on the I-line in exposure equipment. The exposed substrate was developed by spraying in a 0.04% KOH aqueous solution at 25° C., washed with pure water, dried, and post-baked in a convection oven at 220° C. for 30 minutes to produce a cured film as a sample.

2) Optical density (OD) evaluation

The optical density of the above cured film was measured using an OD meter iCFilm from Gretagmacbeth. The measurement results are shown in Table 2 below.

According to Table 2 below, the optical densities of Examples 1 to 5 and Comparative Examples 1 to 7 are all within the range of 0.6 /㎛ or more and 3.0 /㎛ or less.

3) Dielectric constant measurement

The dielectric constant of each sample was measured using a KEY SIGHT B2985A Electrometer/High Resistance Meter. The measurement results are shown in Table 2 below.

According to Table 2 below, in Examples 1 to 5 using a lactam-based black pigment, the dielectric constant is as low as 4.0 or less, so that the black bank using the same is suitable for an insulating film, whereas in Comparative Example 7 using a carbon black pigment, the dielectric constant is as high as 16.8, so that the black bank using the same may not be suitable for an insulating film.

4) Measurement of surface roughness (Ra)

The surface roughness (Ra: surface roughness) of each sample was measured using an AFM (Atomic Force Microscope). The measurement results are shown in Table 2 below.

Also, referring to Fig. 1, in the case of Example 1 (far right) using a millbase having a lactam black pigment and controlling the average particle size to 70 nm or less, it can be confirmed from the SEM photograph results that the surface roughness was improved. On the other hand, in the case of Comparative Examples 1 and 6 having an average particle size exceeding 70 nm, it can be confirmed that both are poor in terms of surface roughness. In addition, even when the average particle size was 70 nm or less, poor surface roughness was exhibited when carbon black pigment was used.

5) Residual Evaluation

The presence or absence of residue was determined for each sample based on the number of pixels in which residue was observed among 50 pixels using an optical microscope. The evaluation results are shown in Table 2 below.

According to Table 2 above, Examples 1 to 5 used a mill base having a lactam black pigment and having an average particle size controlled to 70 nm or less, and accordingly, it was confirmed that the optical density, dielectric constant, and surface roughness were excellent, while residue was prevented.

According to Fig. 1, in the case of Example 1 (the rightmost photo in Fig. 1) using a mill base having a lactam black pigment and having an average particle size controlled to 70 nm or less, it can be confirmed through SEM photography and microscopic examination that residue was prevented.

In contrast, Comparative Examples 1 to 6 in Table 2 above use a millbase having a lactam black pigment and an average particle size exceeding 70 nm, and Comparative Example 7 uses a carbon black pigment satisfying an average particle size of 70 nm or less, and as a result, it can be confirmed that at least one of the optical density, dielectric constant, and surface roughness is deteriorated, or residue is not prevented. In particular, according to Fig. 1, in the case of Comparative Examples 1 and 6 (the two photos on the left of Fig. 1) having an average particle size exceeding 70 nm, residue can be confirmed.

Claims (14)

Containing colorants and dispersants,
The average particle size is less than 70 nm,
A mill base having the above coloring agent as one or more types of lactam black pigments. In claim 1,
Millbase with an average particle size of 40 nm to 65 nm. In claim 1,
A mill base wherein the above coloring agent further comprises at least one color pigment selected from the group consisting of a yellow pigment, a green pigment, a blue pigment, and a purple pigment. In claim 1,
A mill base further comprising at least one of a dispersing binder, a dispersing agent and a solvent. In claim 4,
A mill base comprising, based on 100 parts by weight of mill base, 10 to 50 parts by weight of a colorant, 1 to 30 parts by weight of a dispersant, 1 to 30 parts by weight of a dispersion binder, 0.1 to 5 parts by weight of a dispersing aid, and 10 to 90 parts by weight of a solvent. In claim 1,
The above lactam black pigment is a mill base comprising a compound represented by the following chemical formula 1:
[Chemical Formula 1]

In the above chemical formula 1,
Ra is H or an alkyl group,
R ₄ , R ₅ , R ₆ and R ₇ are the same or different and are each independently H, halogen, -COOR ₈ , -CONR ₈ R ₉ , -OR ₈ , -OOCR ₈ , -OOCNR ₈ R ₉ , OH, CN, NO ₂ , -NR ₈ R ₉ , -NR ₈ COR ₉ , -N=CR ₈ R ₉ , -SR ₈ , -SOR ₈ , -SO _x R ₈ (x=1~3) or -SO ₂ NR ₈ R ₉ , or R ₄ and R ₅ , R ₅ and R ₆ , or R ₆ and R ₇ are directly bonded or bonded to each other through an O, S or NR ₈ bridge to form a ring,
Rb is a single or multiple ring group containing one of N, O, S, CO, and COO,
R ₈ and R ₉ are the same as or different from each other, and are each independently H, C ₁ to C ₁₂ alkyl, C ₃ to C ₁₂ cycloalkyl, C ₂ to C ₁₂ alkenyl, C ₃ to C ₁₂ cycloalkenyl or C ₂ to C ₁₂ alkynyl, and at least one of -CH ₂ -, -CH= and =C= constituting them is substituted with -COO-, -O-, -CONR ₁₀ -, =N-, -NR ₁₀ -, -S- or -CO-, or at least one of the hydrogens bonded to carbon is halogen, -COOR ₁₀ , -CONR ₁₀ R ₁₁ , -OR ₁₀ , -OOCR ₁₀ , -OOCNR ₁₀ R ₁₁ , OH, CN, NO ₂ , -NR ₁₀ COR ₁₁ , -N=CR ₁₀ R ₁₁ , -SR ₁₀ , -SOR ₁₀ , -SOxR ₁₀ (x=1~3), -SO ₂ NR ₁₀ R ₁₀ , or -NR ₁₀ R ₁₁ , wherein R ₁₀ and R ₁₁ are each independently a C ₂ to C ₆ alkyl group, or a group containing O, S or NH. A negative photosensitive resin composition comprising a millbase according to any one of claims 1 to 6; a binder resin; a multifunctional monomer; and a photoinitiator. In claim 7,
The above binder resin is a negative photosensitive resin composition represented by the following chemical formula 2:
[Chemical formula 2]

In the above chemical formula 2,
* indicates the binding position,
X ₁ and X ₂ are the same as or different from each other, and each independently represents one selected from the group consisting of alkylene having 1 to 60 carbon atoms, divalent ethylene oxide, and divalent propylene oxide,
Y is selected from the group consisting of divalent cyclohexene, divalent cyclohexyne, phenylene group and alkyl group having 3 to 10 carbon atoms,
n is a real number between 2 and 50. In claim 7,
Based on the solid content of 100 parts by weight of the entire negative photosensitive resin composition,
A negative photosensitive resin composition comprising 1 part by weight or more and 50 parts by weight or less of a millbase, 10 parts by weight or more and 70 parts by weight or less of a binder resin, 10 parts by weight or more and 50 parts by weight or less of a multifunctional monomer, and 1 part by weight or more and 10 parts by weight or less of a photoinitiator. A black bank comprising a negative photosensitive resin composition according to claim 7 or a cured product thereof. In claim 10,
Black bank with surface roughness (Ra) of 0 nm to 2 nm. In claim 10,
Black bank with an optical density (OD) of 0.3 /㎛ or more and 4.0 /㎛ or less. An organic light-emitting device comprising a black bank according to claim 10. A step of providing a mixture by mixing a colorant and a dispersant;
A step of milling the above mixture into first beads of 0.5 mm or more and 1.2 mm or less to provide a first dispersion by first dispersing; and
Comprising a step of manufacturing a mill base by milling the first dispersion with a second bead of 0.05 mm or more and 0.3 mm or less,
A method for manufacturing a mill base, wherein the mill base is a mill base according to any one of claims 1 to 6.