JP6636081B2 - Photosensitive resin composition, photocurable pattern produced from photosensitive resin composition, and image display device including photocurable pattern - Google Patents

Description

  The present invention relates to a photosensitive resin composition and a photocurable pattern formed therefrom. More specifically, the present invention relates to a photosensitive resin composition containing a photopolymerization initiator and a photocurable pattern formed therefrom.

  In the display field, a photosensitive resin composition is used to form various photo-curing patterns such as a photoresist, an insulating film, a protective film, a black matrix, and a column spacer. Specifically, the photosensitive resin composition is selectively exposed and developed by a photolithography process to form a desired photo-cured pattern. In this process, the yield in the process is improved and the physical properties of the application target are improved. In order to improve the sensitivity, a photosensitive resin composition having high sensitivity is required.

  The pattern formation of the photosensitive resin composition is based on photolithography, that is, a change in polarity of a polymer caused by a photoreaction and a crosslinking reaction. In particular, a change characteristic of solubility in a solvent such as an aqueous alkali solution after exposure is used.

  The formation of a pattern by the photosensitive resin composition is classified into a positive type and a negative type depending on the solubility of the exposed portion in development. Positive-type photoresist is a method in which exposed parts are dissolved in a developing solution to form a pattern. Negative-type photoresist is a type in which exposed parts do not dissolve in a developing solution, and unexposed parts are dissolved to form a pattern. It is a method to do. The positive type and the negative type are different from each other depending on a binder resin, a crosslinking agent and the like to be used.

  When the coating film or pattern formed by the photosensitive resin composition has poor adhesion to the base material, for example, when a resist film formed by applying the photosensitive resin composition is subjected to pattern exposure and development, The formed resist pattern may be disintegrated or peeled off, and problems such as disintegration or peeling of the pattern may occur during etching, and the yield in the mass production process may be reduced. Further, as the size of the display device to which the photosensitive resin composition is applied is reduced, the resolution of the exposure process is required to be improved in order to form a photocurable pattern having a fine line width.

  For example, Korean Patent No. 10-130508 discloses a negative photosensitive resin composition including a copolymer polymerized using a cyclohexenyl acrylate-based monomer.

Korean Patent No. 10-130508

  SUMMARY OF THE INVENTION An object of the present invention is to provide a photosensitive resin composition capable of realizing a highly sensitive photocurable pattern while having excellent substrate adhesion and remaining film ratio.

  Another object of the present invention is to provide a photocurable pattern manufactured using the photosensitive resin composition and an image display device including the photocurable pattern.

1. A photosensitive resin composition comprising an alkali-soluble resin, a polymerizable compound, a photopolymerization initiator, and a solvent, wherein the photopolymerization initiator contains a compound represented by the following Chemical Formula 3 .

2. In the item 1, the photopolymerization initiator is a photosensitive resin composition further comprising a bi-imidazole compound.

3 . In the above item 1, the photopolymerization initiator is a photosensitive resin composition containing 20 to 90 parts by weight of the compound represented by the chemical formula 3 based on 100 parts by weight of the photopolymerization initiator.

4 . In the item 1, the photopolymerization initiator is contained in the photosensitive resin composition in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of a solid content of the photosensitive resin composition.

5 . A photocurable pattern produced from the photosensitive resin composition according to any one of the above items 1 to 4 .

6 . In the item 5 , the photo-cured pattern is a photo-cured pattern selected from the group consisting of an array flattening film pattern, a protective film pattern, an insulating film pattern, a photoresist pattern, a black matrix pattern, and a spacer pattern.

7 . Item 6. An image display device including the photocurable pattern according to item 5 .

  By using the photosensitive resin composition according to the embodiment of the present invention, it is possible to realize a photocurable pattern having excellent sensitivity while having excellent substrate adhesion and remaining film ratio.

  In addition, since the photosensitive resin composition contains a photopolymerization initiator having high light efficiency and excellent behavior control properties, a photocuring pattern having a fine line width can be formed with excellent resolution, and durability can be maintained even under low-temperature curing conditions. An excellent photocuring pattern can be formed.

  Therefore, the photosensitive resin composition can be usefully used for manufacturing a photo-curing pattern such as a spacer pattern and an insulating film pattern, and an image display device including the same.

FIG. 1 is a diagram schematically showing the definition of the T / B ratio.

  Embodiments of the present invention relate to a photosensitive resin composition, and more specifically, include an alkali-soluble resin, a polymerizable compound, a photopolymerization initiator, and a solvent, wherein the photopolymerization initiator has the following chemical formula 1 And a photopolymerization initiator with high light efficiency and excellent behavior control properties, so that a photocuring pattern with a fine line width can be formed with excellent resolution and excellent durability even at low temperature curing conditions. The present invention relates to a photosensitive resin composition capable of forming a photocurable pattern having excellent sensitivity while having excellent substrate adhesion and residual film ratio.

  Hereinafter, embodiments of the present invention will be described in detail.

<Photosensitive resin composition>
(Photopolymerization initiator)
The photosensitive resin composition according to the embodiment of the present invention includes a photopolymerization initiator, and the photopolymerization initiator includes a compound represented by the following Chemical Formula 1.

前記化学式１中、Ａは、ニトロ基またはシアノ基であり、Ｒ_１またはＲ_２は、それぞれ独立して炭素数１〜２０のアルキル基であり、Ｒ_３は、炭素数１〜２０のアルキル基、炭素数６〜２０のアリール基、若しくは炭素数３〜２０のシクロアルキル基であり、Ｒ_４は、オルト、メタまたはパラに位置する、下記化学式２で表される置換基である。

In Chemical Formula 1, A is a nitro group or a cyano group, R ₁ or R ₂ is each independently an alkyl group having 1 to 20 carbon atoms, and R ₃ is an alkyl group having 1 to 20 carbon atoms. R ₄ is a substituent represented by the following chemical formula 2, which is located in the ortho, meta or para position, an aryl group having 6 to 20 carbon atoms, or a cycloalkyl group having 3 to 20 carbon atoms.

前記化学式２中、*は結合部であり、Ｒ_５、Ｒ_６またはＲ_７は、それぞれ独立して炭素数１〜３のアルキル基であり、好ましくは、それぞれ独立してメチル基またはエチル基である。

In the chemical formula 2, * is a bonding part, and R ₅ , R ₆ or R ₇ is each independently an alkyl group having 1 to 3 carbon atoms, and preferably each is independently a methyl group or an ethyl group. is there.

  The photopolymerization initiator can exhibit high light efficiency by including the compound represented by Chemical Formula 1, has an excellent residual film ratio and substrate adhesion, and is included in Chemical Formula 1. The steric hindrance of the phenyl group and the tert-butyl group can improve the behavior control performance of the radical. For example, in the exposure step, radicals can be prevented from diffusing to the non-exposed part due to steric hindrance of the phenyl group and tert-butyl group contained in the chemical formula 1, so that the sensitivity in the exposure step is improved and the development step is performed. Can form a photo-cured pattern with a fine line width with excellent resolution. In addition, the photopolymerization initiator exhibits excellent reactivity even at low temperature curing, and a pattern formed therefrom exhibits excellent durability such as excellent chemical resistance and heat resistance.

  Further, the photosensitive resin composition containing the photopolymerization initiator can be used for forming various patterns used in an image display device, for example, for forming a plurality of insulating patterns. For example, when a spacer pattern is formed from the photosensitive resin composition containing the photopolymerization initiator, a spacer pattern having an improved T / B ratio can be obtained.

  FIG. 1 is a diagram schematically showing the definition of the T / B ratio. Referring to FIG. 1, the T / B ratio is a value obtained by dividing an upper diameter (Top CD) of a spacer pattern by a lower diameter (Bottom CD), and the larger the T / B ratio, the more preferable. In this specification, the upper portion of the pattern is defined as a horizontal plane at a position 95% of the entire height from the bottom surface with respect to the entire height of the pattern. The lower part of the pattern is defined as a horizontal plane at a position 5% of the entire height from the bottom with respect to the entire height of the pattern.

  When a spacer pattern is formed from the photosensitive resin composition containing the photopolymerization initiator, the compound represented by the chemical formula 1 increases steric hindrance of the photopolymerization initiator, and thus effectively controls the behavior of radicals. Since the diffusion of radicals can be prevented, a pattern having a substantially vertical profile can be formed.

  The term “alkyl group” as used herein is intended to include straight or branched chain alkyl groups. The “cycloalkyl group” includes not only a monocyclic hydrocarbon but also a polycyclic hydrocarbon. An "aryl group" is a single or fused ring system derived from an aromatic hydrocarbon by removal of one hydrogen, suitably containing from 4 to 7, preferably 5 or 6, ring atoms in each ring. It is a concept that encompasses the form in which a large number of aryls are connected by a single bond.

  In some embodiments, the photopolymerization initiator may further include at least one selected from the group consisting of an acetophenone-based compound and a biimidazole-based compound in the compound represented by Formula 1. When an acetophenone-based compound and a biimidazole-based compound are further used together, the above-mentioned effect of controlling the behavior of radicals can be replenished or improved at the same time as radical formation sensitivity, and high durability such as excellent chemical resistance and heat resistance can be obtained. It is preferable because a photocurable pattern having the following can be formed.

  Examples of the acetophenone-based compound include diethoxyacetophenone, 2-hydroxy-2-methyl-1-phenylpropan-1-one, benzyldimethylketal, 2-hydroxy-1- [4- (2-hydroxyethoxy) phenyl 2-methylpropan-1-one, 1-hydroxycyclohexylphenyl ketone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinopropan-1-one, 2-benzyl-2-dimethylamino-1 Oligomers of-(4-morpholinophenyl) butan-1-one, 2-hydroxy-2-methyl-1- [4- (1-methylvinyl) phenyl] propan-1-one, diphenyl (2,4,6- Trimethylbenzoyl) -phosphine oxide and the like.

  Examples of the biimidazole compound include, for example, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole and 2,2′-bis (2,3-dichlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole, 2,2'-bis (2-chlorophenyl) -4,4', 5,5'-tetra (alkoxyphenyl) biimidazole, 2,2 ' -Bis (2-chlorophenyl) -4,4 ', 5,5'-tetra (trialkoxyphenyl) biimidazole, imidazole wherein the phenyl group at the 4,4', 5,5'-position is substituted by a carboalkoxy group And the like. Among them, 2,2′-bis (2-chlorophenyl) -4,4 ′, 5,5′-tetraphenylbiimidazole and 2,2′-bis (2,3-dichlorophenyl) -4,4 ′, 5, 5'-tetraphenylbiimidazole and 2,2'4-tris (2-chlorophenyl) -5- (3,4-dimethoxyphenyl) -4 ', 5'-diphenyl-1,1'-biimidazole are preferably used. Can be

  In one embodiment, when the photopolymerization initiator contains both the acetophenone-based compound and the biimidazole-based compound, the molar ratio of the acetophenone-based compound and the biimidazole-based compound is not particularly limited; for example, 1: The molar ratio may be 9 to 9: 1.

  In one embodiment, a photopolymerization initiator commonly used in the art may be further used, as long as the effects of the present invention are not impaired. Examples of the photopolymerization initiator that may be used in combination include, for example, a benzoin compound, a benzophenone compound, a thioxanthone compound, and an anthracene compound. These can be used alone or in combination of two or more.

  In one embodiment, the photopolymerization initiator may be used in combination with a photopolymerization initiation aid from the viewpoint of improving sensitivity and further increasing productivity. Examples of the photopolymerization initiation aid include, for example, amine compounds and carboxylic acid compounds.

  In one embodiment, when the compound represented by the chemical formula 1 and another initiator compound are used in combination as the photopolymerization initiator, the compound is represented by the chemical formula 1 based on 100 parts by weight of the photopolymerization initiator. 20 to 90 parts by weight of the compound, preferably 30 to 60 parts by weight. Within this range, a more excellent T / B ratio value can be obtained during the formation of the spacer pattern.

  In one embodiment, the photopolymerization initiator may be included in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the solid content of the photosensitive resin composition. The above range is preferable because the sensitivity of the photosensitive resin composition is improved, and the strength and smoothness of a formed pattern, for example, a spacer pattern are improved. When the photopolymerization initiator is less than 0.1 part by weight based on 100 parts by weight of the solid content of the photosensitive resin composition, the effect of controlling the behavior of radicals may be insignificant, and 10 parts by weight may be used. If it exceeds, the effect of preventing diffusion of radicals may not be sufficiently realized, and the resolution may be reduced.

(Alkali-soluble resin)
The photosensitive resin composition according to the embodiment of the present invention contains an alkali-soluble resin. The alkali-soluble resin is a component that imparts solubility to the alkali developer used in the developing step and also imparts adhesion to the base material to enable formation of a coating film. For example, the alkali-soluble resin can function as a binder resin of the photosensitive resin composition. The alkali-soluble resin has reactivity by the action of light or heat, and has alkali solubility.

  As the alkali-soluble resin, any alkali-soluble resin used in a photosensitive resin composition in the art can be used without limitation, and when used together with the above-mentioned photopolymerization initiator, excellent reactivity at low temperature curing is obtained. The patterns produced therefrom exhibit high durability, such as excellent chemical and heat resistance.

  In some embodiments, the alkali-soluble resin can further include a repeating unit formed of a monomer known in the art.

  For example, the alkali-soluble resin may further include a repeating unit containing the carboxylic acid group in order to ensure alkali solubility. The repeating unit containing a carboxylic acid group can be formed using a monomer known in the art without any particular limitation. For example, a repeating unit containing a carboxylic acid group is a group consisting of a polyvalent carboxylic acid having two or more carboxyl groups in a molecule, such as an unsaturated monocarboxylic acid or an unsaturated dicarboxylic acid or an unsaturated tricarboxylic acid. The structure may be derived from the selected monomer.

  Examples of the unsaturated monocarboxylic acid include acrylic acid, methacrylic acid, crotonic acid and the like. Examples of the unsaturated polycarboxylic acid include maleic acid, fumaric acid, citraconic acid, mesaconic acid, and itaconic acid. The polycarboxylic acid may be an acid anhydride, and examples of the unsaturated polycarboxylic anhydride include maleic anhydride, itaconic anhydride and citraconic anhydride. Further, the unsaturated polycarboxylic acid may be a mono (2-methacryloyloxyalkyl) ester thereof, for example, mono (2-acryloyloxyethyl) succinate, mono (2-methacryloyloxyethyl) succinate. And mono (2-acryloyloxyethyl) phthalate and mono (2-methacryloyloxyethyl) phthalate. The unsaturated polycarboxylic acid may be a mono (meth) acrylate of a dicarboxy polymer at both terminals, and examples thereof include ω-carboxypolycaprolactone monoacrylate and ω-carboxypolycaprolactone monomethacrylate. Further, the unsaturated polycarboxylic acid may be an unsaturated acrylate containing a hydroxy group and a carboxyl group in the same molecule, and examples thereof include α- (hydroxymethyl) acrylic acid. Among them, acrylic acid, methacrylic acid, maleic anhydride and the like are preferably used because of their high copolymerization reactivity.

Further, the alkali-soluble resin may further include a repeating unit containing an acrylate group in order to impart photo / thermosetting to the alkali-soluble resin. The repeating unit containing an acrylate group can be formed using monomers known in the art without any particular limitation. For example, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) A) Unsubstituted or substituted alkyl ester compounds of unsaturated carboxylic acids such as acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxy-o-phenylphenolpropyl acrylate, aminoethyl (meth) acrylate, cyclopentyl (meth) acrylate , Cyclohexyl (meth) acrylate, methylcyclohexyl (meth) acrylate, cycloheptyl (meth) acrylate, cyclooctyl (meth) acrylate, menthyl (meth) acrylate, cyclopentenyl (meth) acrylate, cyclo Xenyl (meth) acrylate, cycloheptenyl (meth) acrylate, cyclooctenyl (meth) acrylate, mentadenyl (meth) acrylate, isobornyl (meth) acrylate, pinanyl (meth) acrylate, adamantyl (meth) acrylate, norbornyl (meth) acrylate, pinenyl ( Fats such as meth) acrylate, tricyclo [5.2.1.0 ^2,6 ] decanyl (meth) acrylate, 3,4-epoxytricyclo [5.2.1.0 ^2,6 ] decanyl (meth) acrylate Unsaturated carboxylic acid ester compounds containing a cyclic substituent, monosaturated carboxylic acid ester compounds of glycols such as oligoethylene glycol monoalkyl (meth) acrylate, benzyl (meth) acrylate, phenoxy (meth) acrylate Unsaturated carboxylic acid ester compounds having a substituent having an aromatic ring such as acrylate, aromatic vinyl compounds such as styrene, α-methylstyrene and vinyltoluene, carboxylic acid vinyl esters such as vinyl acetate and vinyl propionate, (meth) Acrylonitrile, α-chloroacrylonitrile, vinyl cyanide compounds such as azobisisobutyronitrile, N-cyclohexylmaleimide, maleimide compounds such as N-phenylmaleimide, and unsaturated alicyclic compounds such as norbornene. The structure may be derived from a monomer, but is not limited thereto.

  As used herein, "(meth) acryl-" means "methacryl-", "acryl-", or both.

  The content of the alkali-soluble resin is not particularly limited, and can be appropriately adjusted in consideration of the resolution of the photocured pattern formed therefrom and the uniformity of the pattern. In one embodiment, the content of the alkali-soluble resin may be 10 to 65 parts by weight based on the solid content of the photosensitive resin composition. When the content is within the above range, the solubility in a developer is sufficient and the developability is excellent, and a photocurable pattern having excellent mechanical properties can be formed.

  The weight-average molecular weight of the alkali-soluble resin is not particularly limited, but may be 6,000 to 40,000 from the viewpoint of improving the reactivity of the photosensitive resin composition at low temperatures and improving the chemical resistance. , Preferably 7,500 to 35,000, more preferably 13,000 to 32,000. When the above range is satisfied, the CD-Bias of the pattern is realized in an appropriate range, a pattern having excellent resolution can be formed, and the chemical resistance and pencil hardness can be improved. When the weight-average molecular weight of the alkali-soluble resin exceeds 20,000, the molecular weight becomes too large, the compatibility with other components of the photosensitive resin composition is reduced, and whitening of the coating film occurs in a development stage. In some cases, the CD-Bias characteristics may decrease due to an increase in the line width of the pattern.

(Polymerizable compound)
The photosensitive resin composition according to an exemplary embodiment of the present invention includes a polymerizable compound, and the polymerizable compound may increase a crosslink density during a manufacturing process and enhance a mechanical property of a photocurable pattern.

  As the polymerizable compound, those used in the art can be used without any particular limitation, and examples thereof include monofunctional monomers, difunctional monomers, and other polyfunctional monomers. Although the type is not particularly limited, the following compounds are exemplified.

  Specific examples of the monofunctional monomer include, for example, nonylphenyl carbitol acrylate, 2-hydroxy-3-phenoxypropyl acrylate, 2-ethylhexyl carbitol acrylate, 2-hydroxyethyl acrylate, N-vinylpyrrolidone, and the like. . Specific examples of the bifunctional monomer include, for example, 1,6-hexanediol di (meth) acrylate, ethylene glycol di (meth) acrylate, neopentyl glycol di (meth) acrylate, and triethylene glycol di (meth) acrylate. And bis (acryloyloxyethyl) ether of bisphenol A, 3-methylpentanediol di (meth) acrylate, and the like. Specific examples of other polyfunctional monomers include, for example, trimethylolpropane tri (meth) acrylate, ethoxylated trimethylolpropane tri (meth) acrylate, propoxylated trimethylolpropane tri (meth) acrylate, pentaerythritol tri (Meth) acrylate, pentaerythritol tetra (meth) acrylate, dipentaerythritol penta (meth) acrylate, ethoxylated dipentaerythritol hexa (meth) acrylate, propoxylated dipentaerythritol hexa (meth) acrylate, dipentaerythritol hexa ( (Meth) acrylate, tripentaerythritol octa (meth) acrylate, and the like. Among them, a bifunctional or higher polyfunctional monomer is preferably used.

  The content of the polymerizable compound is not particularly limited, but is, for example, in the range of 10 to 85 parts by weight, preferably 30 to 80 parts by weight based on 100 parts by weight of the solid content of the photosensitive resin composition. When the content of the polymerizable compound is within the above range, excellent durability can be obtained, and the developability of the composition can be improved.

(solvent)
The photosensitive resin composition according to the embodiment of the present invention contains a solvent, and the solvent can be used without any particular limitation as long as it is commonly used in the art.

  Specific examples of the solvent include, for example, ethylene glycol monoalkyl ethers; diethylene glycol dialkyl ethers; ethylene glycol alkyl ether acetates; alkylene glycol alkyl ether acetates; propylene glycol monoalkyl ethers; propylene glycol dialkyl ethers; Glycol alkyl ether propionates; butyl diol monoalkyl ethers; butane diol monoalkyl ether acetates; butane diol monoalkyl ether propionates; dipropylene glycol dialkyl ethers; aromatic hydrocarbons; ketones; And esters; cyclic esters and the like. These solvents can be used alone or in combination of two or more.

  As the solvent, in consideration of coating properties and drying properties, for example, alkylene glycol alkyl ether acetates, ketones, butanediol alkyl ether acetates, butanediol monoalkyl ethers, and esters can be preferably used. More preferably, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, cyclohexanone, methoxybutyl acetate, methoxybutanol, ethyl 3-ethoxypropionate, methyl 3-methoxypropionate and the like can be used.

  The photosensitive resin composition according to the embodiment may include the solvent in an amount of 40 to 95 parts by weight, preferably 45 to 85 parts by weight, based on 100 parts by weight of the total of the photosensitive resin composition. When the above range is satisfied, the coatability is good when applied with a coating apparatus such as a spin coater, a slit and spin coater, a slit coater (sometimes called a “die coater” or a “curtain flow coater”), or an inkjet. Is preferred.

(Additive)
The photosensitive resin composition according to the embodiment of the present invention may contain, if necessary, a filler, another polymer compound, a leveling agent, an adhesion promoter, an antioxidant, an ultraviolet absorber, an anti-agglomeration agent, and a chain transfer agent. And the like.

<Light curing pattern and image display device>
The present invention provides a photocurable pattern formed by the above-described photosensitive resin composition and an image display device including the photocurable pattern.

  The photocurable pattern formed of the above-described photosensitive resin composition has excellent low-temperature curability. For example, the photosensitive resin composition according to the present invention has a heat-curing (prebaking and / or postbaking) temperature of 70%. To 100 ° C. Further, the photocurable pattern produced with the photosensitive resin composition of the present invention has excellent adhesion, chemical resistance, heat resistance, and the like even after low-temperature curing, and has excellent temporal stability.

  In addition, since the above-mentioned photosensitive resin composition contains a photopolymerization initiator having high light efficiency and excellent behavior control characteristics, a photocurable pattern formed therefrom has excellent resolution.

  Thereby, the photocurable pattern formed from the photosensitive resin composition described above can be used for various patterns in an image display device, for example, an adhesive layer, an array flattening film, a protective film, an insulating film pattern, and the like. It can be used for a photoresist, a black matrix, a spacer pattern, a column spacer pattern, a black column spacer pattern, and the like, but is not limited thereto, and is particularly suitable for a spacer pattern or an insulating film pattern.

  An image display device having such a photocurable pattern or using the pattern during the manufacturing process includes, for example, an image display device having a touch panel, a liquid crystal display device, an OLED, a flexible display, and the like. Without limitation, all applicable image display devices known in the art are included.

  In the formation of the photocurable pattern, the photosensitive film can be formed by applying the above-described photosensitive resin composition on a substrate and performing a pre-baking step. Thereafter, an exposure step and, if necessary, a development step may be performed to form a photo-cured pattern, and a post-exposure baking (PEB) step may be further performed.

  In the exposure step, as described above, an acid is generated by the photoacid generator having an improved acidity, and a crosslinking reaction of the binder resin may be induced. In addition, due to the action of the photoacid generator and the polymerization initiator, the difference in physical and chemical properties between the exposed part and the non-exposed part increases, and the resolution of the exposure step can be improved.

  In the exposure step, an ultraviolet light source such as a g-line (wavelength: 436 nm), an h-line, and an i-line (wavelength: 365 nm) can be used. The development step includes a liquid addition method, a dipping method, a spray method, and the like, and an inorganic and / or organic alkaline compound can be used as a developer.

  For example, the inorganic alkaline compound may include an alkali metal salt, and the organic alkaline compound may include an organic hydroxide compound.

  Hereinafter, preferred examples will be presented to facilitate understanding of the present invention, but these examples are merely illustrative of the present invention and do not limit the scope of the appended claims. It will be apparent to those skilled in the art that various changes and modifications can be made to these embodiments within the scope and spirit of the present invention, and these changes and modifications are described in the appended claims. It naturally belongs to the range.

<Production Example 1: Production of alkali-soluble resin (A)>
182 g of propylene glycol monomethyl ether acetate was charged into a flask equipped with a stirrer, a thermometer, a reflux condenser, a dropping funnel, and a nitrogen inlet tube. The atmosphere in the flask was changed from air to nitrogen, and then heated to 100 ° C. . Thereafter, 35.4 g (0.30 mol) of vinyl toluene, 36.0 g (0.50 mol) of acrylic acid, 59.6 g (0.2 mol) of 2-hydroxy-o-phenylphenolpropyl acrylate and propylene glycol monomethyl ether A solution obtained by adding 3.6 g of azobisisobutyronitrile to a mixture containing 136 g of acetate was dropped into the flask over 2 hours from a dropping funnel, and stirring was further continued at 100 ° C. for 5 hours. Then, the atmosphere in the flask was changed from nitrogen to air, and 22.5 g of glycidyl methacrylate (0.15 mol, (50 mol% based on acrylic acid used in this reaction)), 0.9 g of trisdimethylaminomethylphenol and hydroquinone 0.145 g was charged into the flask, and the reaction was continued at 110 ° C. for 6 hours to obtain an unsaturated group-containing alkali-soluble resin A having an acid value of solids of 121.1 mgKOH / g. The weight average molecular weight in terms of polystyrene measured by GPC was 31,000, and the molecular weight distribution (Mw / Mn) was 2.2.

<Examples and comparative examples>
The photosensitive resin compositions of Examples 1 to 9 and Comparative Examples 1 to 3 were produced with the compositions and contents (unit: parts by weight) shown in Table 1 below.

<Example of experiment>
A 2-inch square glass substrate (Eagle 2000; manufactured by Corning Incorporated) was sequentially washed with a neutral detergent, water, and alcohol, and then dried. After spin-coating each of the photosensitive resin compositions prepared in the above Examples and Comparative Examples on this glass substrate, prebaking was performed at 90 ° C. for 3 minutes in a clean oven. After cooling the prebaked substrate to room temperature, the distance between the prebaked substrate and the quartz glass photomask was set to 150 μm, and an exposure machine (TME-150RSK; manufactured by Topcon Co., Ltd.) was used to expose 60 mJ / cm ² ( (With reference to 405 nm). At this time, the irradiation of the polymerizable resin composition was performed by passing light emitted from an ultra-high pressure mercury lamp through an optical filter (LU0400; manufactured by Asahi Spectroscopy Co., Ltd.) to cut light of 400 nm or less. As the photomask, a photomask having a circular light-transmitting portion (pattern) having a diameter of 10 μm and having a pattern interval of 100 μm was used.

  After light irradiation, the coating was immersed in an aqueous developer containing 0.12% of a nonionic surfactant and 0.04% of potassium hydroxide at 25 ° C. for 100 seconds, developed, and washed with water. Thereafter, post-baking was performed at 220 ° C. for 20 minutes in an oven. The obtained film thickness was 3 μm. The film thickness was measured using a film thickness measuring device (DEKTAK 6M; manufactured by Veeco). The patterns thus obtained were evaluated for physical properties as described below, and the results are shown in Table 2 below.

<Evaluation of physical properties>
(1) Evaluation of Resolution The pattern size at a position 1.5 μm from the bottom of the pattern obtained above was measured using a three-dimensional shape measuring device (SIS-2000 system; manufactured by SNU Precision), and the pattern size was measured. The difference was calculated as CD-bias as follows, and the resolution was measured. The closer the value of CD-bias is to 0, the better the resolution can be evaluated. (+) Means that the pattern is larger in size than the mask, and (-) means that the pattern is smaller in size than the mask.
CD-bias = (formed pattern size) − (mask size used during formation)

(2) Evaluation of the top-bottom width ratio (T / B ratio) of the pattern The bottom surface of the Dot pattern obtained in (1) above was measured using a three-dimensional shape measuring device (SIS-2000 Systems; manufactured by SNU PRECISION). 5% of the total height from the floor is defined as Bottom CD (a), 95% of the total height from the floor is defined as Top CD (b), and the length of (b) is defined as the length of (a). Then, the value multiplied by 100 (= b / a × 100) was defined as the T / B ratio.

(3) Evaluation of Development Adhesion Force The development adhesion was evaluated by using a microscope to evaluate a pattern in which a circular pattern having a diameter (size) of 10 μm and a thickness of 3 μm was formed using 1000 photomasks, and the number of missing patterns was evaluated. And the developing adhesion (%) was calculated from the following equation (I). The results are shown in Table 2 below.

  Development adhesion (%) = [1000− (number of missing patterns)] / 1000 × 100 (I)

  As shown in Table 2, in Examples including the photopolymerization initiator according to the present invention, a pattern having better chemical and mechanical properties was formed overall than in Comparative Examples.

  Examples 1 and 2, which contain the compound represented by Formula 1, a biimidazole-based compound and an acetophenone-based compound as photopolymerization initiators, exhibit the best CD-bias, T / B ratio, and development adhesion. It was evaluated as having. In Examples 3 and 4, in which the photosensitive resin composition contained the compound represented by Formula 1 in a slightly excessive amount, the resolution and mechanical properties were slightly reduced.

  In Examples 5 and 7, in which the compound represented by Chemical Formula 1 was added to the photopolymerization initiator in a slightly smaller amount than in Example 1, the value of the T / B ratio was slightly lowered, and the photopolymerization was started. In Example 6, in which the compound represented by Chemical Formula 1 was added in a slightly larger amount than in Example 1, it was confirmed that the T / B ratio and the developing adhesion property were slightly reduced.

  Examples 8 and 9 containing only the compound represented by Formula 1 as a photopolymerization initiator exhibited high resolution due to the high light efficiency and the effect of controlling the radical behavior, but the development adhesion was slightly high. Diminished.

  On the other hand, the comparative example exhibited poor CD-bias and T / B ratio as a whole, and was inferior in resolution to the example. In particular, in the case of Comparative Example 2, the developing adhesion was not very good.

Claims (7)

An alkali-soluble resin, a polymerizable compound, a photopolymerization initiator, and a solvent,
The photopolymerization initiator is a photosensitive resin composition containing a compound represented by the following chemical formula 3 .

The photopolymerization initiator The photosensitive resin composition according to claim 1, further comprising a bi-imidazole compound. 2. The photosensitive resin composition according to claim 1, wherein the photopolymerization initiator contains 20 to 90 parts by weight of the compound represented by Chemical Formula 3 based on 100 parts by weight of the photopolymerization initiator. 3.   The photosensitive resin composition according to claim 1, wherein the photopolymerization initiator is contained in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the solid content of the photosensitive resin composition. Photocuring pattern produced in the photosensitive resin composition according to any one of claims 1-4. The light curing pattern according to claim 5 , wherein the light curing pattern is selected from the group consisting of an array flattening film pattern, a protective film pattern, an insulating film pattern, a photoresist pattern, a black matrix pattern, and a spacer pattern. An image display device including the photocurable pattern according to claim 5 .

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