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JP-7856097-B2 - Positive-type photosensitive pigment composition and a cured film containing the cured product thereof, and organic EL display device

JP7856097B2JP 7856097 B2JP7856097 B2JP 7856097B2JP-7856097-B2

Inventors

  • 石川 暁宏
  • 杉原 充
  • 佐伯 昭典
  • 山本 洋平

Assignees

  • 東レ株式会社

Dates

Publication Date
20260511
Application Date
20230316
Priority Date
20220404

Claims (13)

  1. (a) A triphendioxazine pigment having a carboxylic acid amide bond and/or a carboxylic acid ester bond, (b) A resin having the structure represented by formula (1) and/or formula (2), (c) Photoacid generator and, (d) A positive-type photosensitive pigment composition containing an organic solvent. (In equation (1), n 1 is an integer and represents either 1 or 2.) When n1 is 1, R1 represents a divalent organic group with 2 to 30 carbon atoms that does not contain a carboxylic acid amide bond or a carboxyl group. When n1 is 2, R1 represents a trivalent organic group with 5 to 30 carbon atoms that does not contain a carboxylic acid amide bond or a carboxyl group. (* indicates a bonding site with a carbon atom.) (In formula (2), R2 represents a trivalent organic group having 5 to 30 carbon atoms that does not contain a carboxylic acid amide bond or a carboxyl group. * represents a bonding site with a carbon atom.)
  2. The positive-type photosensitive pigment composition according to claim 1, wherein component (a) contains a triphendioxazine pigment represented by formula (4) and/or a triphendioxazine pigment represented by formula (5). (In formula (4), R3 and R4 each independently represent an alkyl group having 1 to 8 carbon atoms. R5 and R6 each independently represent an alkyl group having 1 to 8 carbon atoms, a phenyl group substituted with an alkyl group having 1 to 8 carbon atoms, or an unsubstituted phenyl group. R7 and R8 each independently represent -NH- or an oxygen atom. R9 , R10 , R11 , R12, R13 , R14 , R15 , R16 , R17 , and R18 each independently represent a hydrogen atom, an alkyl group having 1 to 4 carbon atoms, or an alkoxy group having 1 to 4 carbon atoms. R19 and R20 represent -CONH-.) (In formula (5), R 21 and R 22 each independently represent a hydrogen atom and an alkyl group having 1 to 8 carbon atoms. R 23 and R 24 each independently represent an alkyl group having 1 to 8 carbon atoms, a phenyl group substituted with an alkyl group having 1 to 8 carbon atoms, or an unsubstituted phenyl group. R 25 and R 26 each independently represent -NH- or an oxygen atom.)
  3. The positive-type photosensitive pigment composition according to claim 1, wherein the component (a) contains a triphendioxazine pigment represented by formula (6). (In formula (6), R 27 , R 28 , R 29 , and R 30 each independently represent an alkyl group having 1 to 4 carbon atoms.) R31 , R32 , R33 , R34 , R35 , R36 , R37 , R38 , R39 , and R40 each independently represent a hydrogen atom, a C1-C4 alkyl group, or a C1-C4 alkoxy group. R 41 and R 42 represent -CONH-.
  4. The positive-type photosensitive pigment composition according to claim 1, wherein the component (a) contains a triphendioxazine pigment represented by formula (7). (In formula (7), R 43 , R 44 , R 45 , and R 46 each independently represent an alkyl group having 1 to 4 carbon atoms.)
  5. Furthermore, the positive-type photosensitive pigment composition according to claim 1, further comprising (e) an organic dye having a sulfo group bonded to a carbon atom constituting an aromatic ring and/or a carboxyl group bonded to a carbon atom constituting an aromatic ring, and having no chlorine atoms in the molecule.
  6. The positive-type photosensitive pigment composition according to claim 5, wherein the component (e) contains at least one selected from the group consisting of triphendioxazine-based dyes, perylenebisimide-based dyes, and anthraquinone-based dyes.
  7. The positive-type photosensitive pigment composition according to claim 5, wherein the (e) component contains a compound represented by formula (62) and/or a compound represented by formula (63). (In formula (62), R 57 and R 58 each independently represent -NH- or an oxygen atom.) R 59 and R 60 each independently represent an alkyl group having 1 to 4 carbon atoms. R 61 and R 62 each independently represent -NH- or -CONH-. R 63 , R 64 , R 67 , and R 68 each independently represent -SO₃H , -SO₃- , -COOH , or -COO- . R 65 and R 66 each independently represent an alkyl group having 1 to 4 carbon atoms or an alkoxy group having 1 to 4 carbon atoms. n 9 and n 10 are integers and each independently represent 0 or 1. n 11 , n 12 , n 13 , and n 14 are integers and each independently represent 0 to 2. n 15 is an integer and represents 0 or 1. The sum of n9 , n11 , and n15 is 2 or less, and the sum of n10 , n12 , and n15 is 2 or less. If n15 is 0, the sum of n11 and n12 is between 1 and 3. If n15 is 1, the sum of n11 , n12 , n13 , and n14 is between 1 and 3. (In formula (63), R 69 and R 70 each independently represent -NH- or an oxygen atom.) R 71 and R 72 each independently represent an alkyl group having 1 to 4 carbon atoms. R 73 , R 74 , R 75 , and R 76 each independently represent -SO₃H , -SO₃- , -COOH , or -COO- . R 77 and R 78 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. n 16 , n 17 , n 18 , and n 19 are integers, each independently representing 0 or 1. The sum of n 16 , n 17 , n 18 , and n 19 is between 1 and 3.
  8. The positive-type photosensitive pigment composition according to claim 1, wherein the component (b) contains a resin having a repeating unit represented by formula (36) and a structure represented by formula (47). (In formula (36), R 47 represents a divalent organic group with 5 to 30 carbon atoms that does not contain a carboxylic acid amide bond or a carboxyl group. R 48 represents a 3 to 6 valent organic group with 6 to 40 carbon atoms that does not contain a hydroxyl group. n 2 is an integer representing 1 to 4. * 1 represents the bonding site with a nitrogen atom. * 2 represents the bonding site with a carbon atom.) (In formula (47), R 113 represents a divalent organic group with 5 to 30 carbon atoms that does not contain a carboxylic acid amide bond or a carboxyl group. R 114 represents a 3 to 6 valent organic group with 6 to 40 carbon atoms that does not contain a hydroxyl group. n 32 is an integer representing 1 to 4. * 3 represents the bonding site with the nitrogen atom.)
  9. Furthermore, the positive-type photosensitive pigment composition according to claim 1, further comprising (g) a perylene-based black pigment having a benzimidazole skeleton.
  10. A cured film comprising a cured product of a positive-type photosensitive pigment composition according to any one of claims 1 to 9.
  11. An organic EL display device comprising the cured film described in claim 10.
  12. An organic EL display device comprising a pixel splitting layer containing a triphendioxazine pigment represented by formula (7). (In formula (7), R 43 , R 44 , R 45 , and R 46 each independently represent an alkyl group having 1 to 4 carbon atoms.)
  13. The organic EL display device according to claim 12, wherein the pixel splitting layer further contains (e) a triphendioxazine dye having a sulfo group bonded to a carbon atom constituting an aromatic ring and/or a carboxyl group bonded to a carbon atom constituting an aromatic ring, and having no chlorine atoms in the molecule.

Description

This invention relates to a positive-type photosensitive pigment composition, a cured film containing the cured product thereof, and an organic EL display device. In recent years, products incorporating flexible organic electroluminescent (EL) display devices have been developed. By eliminating the use of thick polarizing plates that were conventionally placed on the front of the panel, not only is the flexibility of the panel improved, but brightness loss is eliminated, and an extension of the lifespan of the light-emitting pixels is expected. The light-emitting elements of organic EL display devices have patterns that function as insulating layers called pixel division layers or pixel definition layers to separate each light-emitting pixel. In order to replace the function of the polarizing plate, it is necessary to add a function that suppresses the reflection of external light such as sunlight, and technology to give light-shielding properties to the pixel division layer is attracting attention. In addition to increasing the resolution by narrowing the aperture width of the pixel division layer and reducing the size of the light-emitting pixels, further improvement in light resistance reliability is also required to extend the product lifespan of the display device. Incidentally, in order to significantly improve the yield during panel production, a technique is known in which a convex spacer layer is formed on a part of the surface of the pixel division layer when pattern-depositing the light-emitting layer at the openings of the pixel division layer. This reduces the contact area between the deposition mask and the pixel division layer, thereby suppressing the occurrence of defects. As a method for forming the pixel division layer and spacer layer, a technique is known in which the pixel division layer and spacer layer are formed together by a photolithography method that includes an exposure step of irradiating exposure light including at least near-ultraviolet light through a halftone exposure mask having fully transparent, semi-transparent, and shielded areas in its plane (halftone processing). Halftone processing is economically advantageous because it can significantly reduce manufacturing process costs compared to two-layer processing, in which the spacer layer is further laminated after the pixel division layer is formed. As a material for simultaneously forming a light-shielding pixel division layer and a spacer layer, a negative-type photosensitive pigment composition containing a triphendioxazine pigment, C.I. Pigment Violet 37, and a polymer-type dispersant having an N,N-dialkylaminoalkyl group is disclosed in Technical Document 1. On the other hand, as a material for forming a light-shielding pixel-splitting layer, Patent Document 2 discloses a positive-type photosensitive pigment composition containing an organic pigment that has been pseudo-blackened by mixing C.I. Pigment Yellow 192, C.I. Pigment Red 179, and C.I. Pigment Blue 60, a perylene-based dye derivative type dispersant having an N,N-dialkylaminoalkyl group, and a polymer-type dispersant having a phosphate group. International Publication No. 2019/087985International Publication No. 2019/065359 This image shows a cross-section of the substrate used for evaluating the minimum required exposure amount, obtained in Example 1, observed using a scanning electron microscope (SEM).This is a schematic diagram of a light-emitting pixel that has light-emitting areas but no non-light-emitting areas.This is a schematic diagram of a light-emitting pixel having light-emitting and non-light-emitting areas.This is the manufacturing process for an organic EL display device, including the pixel division layer formation step, in all examples and comparative examples. The present invention will be described in detail below. A numerical range expressed using "~" means a range that includes the values written before and after "~" as the lower and upper limits. A pixel division layer refers to the pixel division layer provided by an organic EL display device and does not include the black matrix of a liquid crystal display device. Visible light refers to light in the region of wavelengths from 380 nm to less than 780 nm, and near-ultraviolet light refers to light in the region of wavelengths from 200 nm to less than 380 nm. Light shielding refers to the function of reducing the intensity of transmitted light relative to the intensity of light incident perpendicular to the cured film, and light shielding property refers to the degree to which visible light is shielded. Transmittance refers to light transmittance. Weight-average molecular weight (Mw) is a value obtained by analysis using gel permeation chromatography (GPC) with tetrahydrofuran as the carrier and converted using a calibration curve with standard polystyrene. The abbreviation "C.I." used in the names of some colorants stands for Color Index Generic Name. Based on the Color Index issued by