Residue-free black color paste for BPDL, preparation method of residual-free black color paste and black photoresist

Abstract

The invention belongs to the technical field of photoresist, and relates to residue-free black color paste for BPDL, a preparation method of the residue-free black color paste and black photoresist. The color paste comprises the following raw materials in parts by weight: 10-25 parts of black modified organic pigment, 3-10 parts of first dispersion resin, 3-10 parts of a dispersing agent and 70-84 parts of a first organic solvent, the black modified organic pigment is obtained by carrying out acid treatment on a black organic pigment; impurities and pollutants on the surface of the pigment can be removed through acid treatment, meanwhile, surface charges and hydrophilicity of pigment particles can be changed, the hydrophilicity of the pigment is improved, and therefore the dispersity of the pigment in a water phase is improved. Besides, after acid treatment, some functional groups may be formed on the surface of the pigment, and the functional groups can interact with functional groups in the dispersing agent, so that the adsorption capacity of the dispersing agent is enhanced. In short, the acid treatment can improve the stability of the pigment in a dispersion medium, reduce precipitation and aggregation phenomena, and realize no residue.

Description

Technical Field

[0001] The invention belongs to the technical field of photoresists and relates to a residue-free black color paste for BPDL and a preparation method thereof, and a black photoresist. Background Art

[0002] The main components of photoresist are resin, photosensitive agent, solvent, surfactant and other additives. Resin and photosensitive agent are used together as the main functional components of photoresist to play a photosensitive role. Different types of photoresists use different resins and photosensitive agents. In addition to the above components, color and black photoresists for panels also require pigment dispersion or dye to present color. Color paste is one of the important components of black BPDL (Black Pixel Define Layer), and its quality determines the uniformity of the BPDL film surface.

[0003] At present, the color paste used in the black BPDL photoresist of many domestic companies has the problem of color paste residue in the pattern holes after photolithography, which affects the quality of the imaging pattern. On the one hand, this is because these color pastes are not based on the application field of photoresist and have not matched the corresponding pigments and dispersants according to the application type; on the other hand, it is because the color paste composition is not clear when BPDL is prepared, so the various components in the color paste affect the BPDL components and cause residues.

[0004] In this regard, the existing patent document (publication number: CN116651346A, publication date: August 29, 2023) discloses a method for preparing a color paste for black photoresist, and its preparation method and application, by adding resin and solvent into a reactor for uniform dispersion and stirring, and then successively adding a dispersant and a pretreated black pigment for dispersion and stirring to obtain a color paste precursor; the color paste precursor is nano-processed to obtain a photoresist color paste; wherein the black pigment is pretreated to improve its own dispersibility and insulation, and the prepared color paste has high stability and good insulation performance, is not easy to generate electrostatic interference, and has excellent light shielding properties, but there is still a problem of residue in the pores.

[0005] In view of this, the present invention is proposed. Summary of the invention

[0006] The object of the present invention is to overcome the disadvantages of the prior art and provide a residue-free black color paste for BPDL and a preparation method thereof, and a black photoresist.

[0007] The objective of the present invention is achieved through the following technical solutions:

[0008] In one aspect, the present invention provides a residue-free black color paste for BPDL, comprising the following raw materials in parts by weight: 10 to 25 parts of a black modified organic pigment, 3 to 10 parts of a first dispersing resin, 3 to 10 parts of a dispersant, and 70 to 84 parts of a first organic solvent; wherein,

[0009] The black modified organic pigment includes an organic black pigment subjected to acid treatment; after the acid treatment, the acid can provide protons (H+) to protonate basic groups such as amino and imino groups in the black pigment; in addition, the acid helps to adjust the pH value of the pigment, which can increase the solubility of the pigment and make it more easily soluble in the solvent.

[0010] It should be noted that the weight percentage of each raw material in the black color paste can be within the above range, and can be adaptively adjusted according to the actual performance index requirements. For example, the weight percentage of the black modified organic pigment can be 10 parts, 12 parts, 15 parts, 18 parts, 20 parts, 22 parts, 25 parts, etc., which are not listed one by one; the amount of the acid containing the acidic group is 3 parts, 5 parts, 6 parts, 8 parts, 10 parts, etc., which are not listed one by one; the weight percentage of the first dispersing resin can be 3 parts, 5 parts, 6 parts, 8 parts, 10 parts, etc., which are not listed one by one; the weight percentage of the dispersant can be 3 parts, 5 parts, 6 parts, 8 parts, 10 parts, etc., which are not listed one by one; the weight percentage of the first organic solvent can be 70 parts, 72 parts, 75 parts, 78 parts, 80 parts, 82 parts, 84 parts, etc., which are not listed one by one.

[0011] The black organic pigments used in the above-mentioned black color paste include phthalocyanine black, pyrrole black, aniline black, amide black, etc. At present, the black organic pigments used in the black color paste can be selected from BASF L0080, BASF L0090, Runba P0080A (particle size 0.3-2 μm), Runba P0080E (pH 4-5), Runba P0085, Runba P0086 (pH 6-7), Runba I0330 (pH 6-8, average particle size 1.2 μm), etc.; preferably, the black organic pigment used in the black color paste is BASF L0080 (pH 4-7), which has higher weather resistance and blackness.

[0012] Specifically, the acid treatment is as follows: adding an acid containing an acidic group to the black organic pigment, adding a solvent for heating reaction, and obtaining the modified organic black pigment, namely the black modified organic pigment, through centrifugation, washing, and vacuum drying.

[0013] Furthermore, the acid containing an acidic group includes an organic acid and / or an inorganic acid, the organic acid includes formic acid, acetic acid, propionic acid, 2-hydroxypropionic acid or 2-phenylpropionic acid, and the inorganic acid includes phosphoric acid, sulfuric acid, chloric acid or manganese acid; when actually selected, the acid containing an acidic group can be a mixture of any two of the above acids, that is, it can include any two of the organic acids, any two of the inorganic acids, any one of the organic acids and any one of the inorganic acids.

[0014] In the present invention, the acid containing an acidic group is selected from any two organic acids. Too much or too little addition of the acid will affect the subsequent dispersion with the dispersant, so the amount of the acid containing an acidic group is selected to be 3% to 10% of the weight of the black organic pigment. Preferably, the acid containing an acidic group is selected from a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the mass ratio of 2-hydroxypropionic acid to 2-phenylpropionic acid is (1.5 to 2.5):1.

[0015] It should be noted that the hydroxyl group in 2-hydroxypropionic acid can form hydrogen bonds with other functional groups in organic black pigments, which helps to stabilize the dispersion state of the pigment particles and enhance their tinting power. The benzene ring in 2-phenylpropionic acid can form a π-π stacking effect with other aromatic compounds in the pigment, enhancing the dispersibility and tinting power of the pigment, and further enhancing its ability to absorb ultraviolet and infrared rays, thereby improving its blackness and stability. In addition, the carboxyl groups in 2-hydroxypropionic acid and 2-phenylpropionic acid can dissociate in water to generate negative charges, forming complex bonds with the surface groups of the pigment, further enhancing the dispersibility of the pigment. The above-mentioned hydroxyl groups, carboxyl groups and benzene rings work synergistically to change the surface properties of the pigment through chemical adsorption and coordination. The addition of organic acids can adjust the pH value of black organic pigments and improve the stability, dispersibility and tinting power of the pigment.

[0016] Specifically, the first dispersed resin is polyvinyl alcohol resin, acrylate resin, polyurethane-acrylic resin, epoxy-acrylic resin, aliphatic polyurethane-acrylic resin, silicon-modified acrylic resin, polyetheramine-modified acrylate or rosin-modified maleate resin.

[0017] Preferably, the weight proportion of the first dispersing resin is 3 to 10 parts, and one or both of pure acrylic resin or modified acrylic resin are selected. For example, it can be Lisennoko SP-DW-W1002 (double bond equivalent 1500meq / g, molecular weight 11000, acid value 97mgKOH / g), SP-DW-W1001, BURNOCK WD-570, AC 2403VP. Considering the dispersibility, developability and weather resistance of the pigment, the double bond equivalent of the first dispersing resin is 1000 to 1500meq / g, the viscosity is small, the acid value is 20 to 100mgKOH / g, the molecular weight is selected from 5000 to 15000, and the PDI value (polydispersity index) is less than 3.

[0018] In terms of mechanism of action:

[0019] The first dispersing resin can improve the wetting and dispersion of the pigment: improve the dispersion performance of the pigment particles, make the pigment more evenly distributed in the carrier medium, reduce pigment agglomeration, and improve the transparency and gloss of the color paste. The first dispersing resin can enhance the adhesion and hiding power of the pigment, improve the rheology and thixotropy of the color paste; the first dispersing resin can also adjust the viscosity and flow properties of the color paste, making it easier to apply while maintaining good storage stability. While a higher molecular weight usually helps to improve the adhesion and dispersibility of the dispersing resin, too high a molecular weight may cause the solubility of the dispersing resin in the medium to decrease. In addition, the lower the PDI value (polydispersity index), the more uniform the molecular weight distribution of the first dispersing resin and the better the dispersion effect.

[0020] Acids containing acidic groups, with higher acid values, can increase the affinity between the first dispersing resin and the pigment surface, thus improving the dispersing effect. However, too high an acid value may reduce the solubility of the first dispersing resin in the medium, thus affecting the stability of the color paste.

[0021] To prevent the film from falling off due to excessive addition of dispersant, the weight of the dispersant is 3 to 10 parts; and the dispersant can be at least one of anionic dispersants, cationic dispersants, nonionic dispersants and polymer dispersants.

[0022] Anionic dispersants include anionic polyacrylamide, ethoxylated tristyrylphenol potassium phosphate, sodium secondary alkyl sulfonate, polyacrylate or polymethacrylate;

[0023] Cationic dispersants include ammonium salts or quaternary ammonium salts;

[0024] Nonionic dispersants include tristyrylphenol polyoxyethylene ether and its ethylene oxide, ethoxylated dispersants, polyoxyethylene fatty acids or polyoxyethylene alcohols;

[0025] The polymer dispersant includes an acrylic polymer dispersant, which contains an appropriate amount of acid value and amine value, the acid value is 0 to 30 mg KOH / g, the amine value is 10 to 20 mg KOH / g, and the weight parts are 3 to 10 parts. For example, it can be: EFKA4310, BYK-LPN 21116, EFKAPU4050 (amine value 12 mg KOH / g), BYKJET-9131, BYKJET-9150, BYKJET-9151, DISPERBYK-168TF or PB821. The present invention has no special limitation on the source of the polymer dispersant, and commercially available products known to those skilled in the art can be used.

[0026] Furthermore, the acrylic polymer dispersant contains an acrylic block copolymer, which can have an affinity with the surface of the black modified organic pigment particles, can effectively adhere to the surface of the pigment particles, help stabilize the pigment and improve its dispersibility in the medium. In addition, the acrylic block copolymer has a longer molecular chain and has good segment movement ability. During the dispersion process, the polymer segment can rotate and bend around the pigment particles, forming a three-dimensional barrier around the pigment particles, thereby reducing the contact area between the pigment particles, reducing the aggregation tendency, and helping to prevent the aggregation and sedimentation of the pigment particles. This steric hindrance effect is conducive to maintaining the stable dispersion of the pigment in the system, and at the same time, it can improve the wettability of the pigment particles, reduce the interfacial tension between the particles, and help the uniform dispersion of the pigment.

[0027] In addition, acid treatment and dispersant act synergistically. Acid treatment changes the properties of the pigment surface and provides more active sites for the adsorption of the dispersant, thereby improving the adsorption efficiency and dispersion effect of the dispersant.

[0028] The first organic solvent: 70 to 84 parts by weight, used to provide dispersion space for the pigment so that there is enough space between particles. Optionally, the organic solvent can be: propylene glycol monomethyl ether, propylene glycol methyl ether, ethylene glycol methyl ether acetate, ethylene glycol dimethyl ether, propylene glycol monomethyl ether acetate, etc. Preferably, the organic solvent is one or both of propylene glycol methyl ether acetate and propylene glycol methyl ether.

[0029] On the other hand, the present invention also provides a method for preparing a residue-free black color paste for BPDL: adding a black modified organic pigment, a first dispersing resin, and a dispersant in specific weight portions to a first organic solvent, mixing, and then grinding twice to obtain the color paste.

[0030] The grinding includes: first using 0.3-0.4nm zirconium oxide beads to grind for 3-5 hours to obtain a dispersion with a particle size of less than 300nm; then using 0.1nm zirconium oxide beads to grind in a dispersion bead mill for 10-14 hours to obtain a black dispersed color paste with a particle size of less than 100nm.

[0031] Preferably, the present invention selects 20g of black modified organic pigment, 6g of dispersant EFKA 4310, whose Nv (solid content) = 50%, 8g of first dispersing resin (Nv = 50%), and 80g of first organic solvent PMA and mixes them evenly, grinds them with 0.3-0.4nm zirconium oxide beads for 4h to obtain a dispersion with a particle size of <300nm; then grinds them in a dispersion bead mill with 0.1nm zirconium oxide beads for 12h to obtain a black dispersed color paste with a particle size of <100nm or less.

[0032] In addition, the present invention also discloses a black photoresist, which comprises, by weight: 30-50 parts of black color paste, 5-20 parts of a second dispersion resin, 8-12 parts of a photocurable monomer, 3-5 parts of a photoinitiator, and 20-50 parts of a second organic solvent.

[0033] Specifically, the double bond equivalent of the second dispersion resin is 600-800 meq / g, for example: Lisennoko SP-W2000, SP-2000M3, SP-2000A4. Wherein, double bond equivalent = molecular weight of the second dispersion resin (g) / number of unsaturated double bonds in the second dispersion resin (mol). The double bond equivalent of the second dispersion resin should be less than the double bond equivalent of the first dispersion resin, because:

[0034] When preparing black color paste, it is necessary to form a cured network quickly and evenly. The dispersion resin with high double bond equivalent (i.e., the first dispersion resin) can form a three-dimensional network structure faster, and the black modified organic pigment will be uniformly dispersed together with the dispersant to ensure that the color paste maintains good optical properties, such as color uniformity and transparency. When using the above-mentioned black color paste to prepare black photoresist, the photocuring process should be controlled more accurately and meticulously to avoid the problems of viscosity and surface tension caused by premature curing or uneven curing. The dispersion resin with low double bond equivalent (i.e., the second dispersion resin) can reduce its influence on the sensitivity and resolution of the photoresist, so that the resin has better surface properties after curing, such as lower surface tension, which is very important to keep the uniform distribution of the photoresist and avoid bubble formation. At the same time, the dispersion resin with low double bond equivalent can also improve the etching resistance and mechanical properties of the photoresist, thereby achieving higher resolution and more accurate shape control, which is very important for high-precision microelectronics applications.

[0035] Specifically, the photocurable monomers include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 1,6-hexanediol diacrylate (HDDA), pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, pentaerythritol hexa(meth)acrylate, dipentaerythritol di(meth)acrylate, dipentaerythritol tri(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, ethylene glycol monomethyl ether (meth)acrylate, tri(meth)acryloyloxyethyl phosphate, novolac epoxy (meth)acrylate and the like.

[0036] Specifically, the second organic solvent is the same as the first organic solvent, and can be selected from propylene glycol monomethyl ether, propylene glycol methyl ether, ethylene glycol methyl ether acetate, ethylene glycol dimethyl ether or propylene glycol monomethyl ether acetate, etc. Propylene glycol methyl ether acetate or propylene glycol methyl ether is preferred.

[0037] Further, the photoinitiator includes: 2-((benzoyloxy)imino)-1-(4-(phenylthio)phenyl)octan-1-one (OXE-1), 1-phenyl-1,2-propanedione-2-(o-ethoxycarbonyl)oxime, o-benzoyl-4'-(mercaptophenyl)benzoyl-hexyl-ketone oxime, 1-[9-ethyl-6-benzoyl-9H-carbazole-3-yl]nonane-1,2-nonane-2-oxime-O-benzoate, 1-[9-ethyl-6-benzoyl-9H-carbazole-3 -yl] octan-1-one oxime-O-acetate, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazole-3-yl]ethanone 1-(O-acetyl oxime), 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoyl oxime), 1,2-butanedione-1-[4-(phenylthio)phenyl]-2-(O-benzoyl oxime), 1,2-octanedione-1-[4-(phenylthio)phenyl]-2-[O-(4-methylbenzoyl oxime)], and the like, and mixtures thereof.

[0038] Finally, the present invention also provides a method for preparing black photoresist, wherein the raw materials are added into a reaction container according to corresponding weight parts, and mixed and stirred by a stirrer to obtain black photoresist, wherein the black color paste is 30 to 50 parts, the second dispersion resin is 5 to 20 parts, the photocurable monomer is 8 to 12 parts, the photoinitiator is 3 to 5 parts, and the second organic solvent is 20 to 50 parts.

[0039] It should be noted that the weight percentage of each raw material in the black photoresist can be within the above range and can be adaptively adjusted according to the actual performance index requirements. For example, the weight percentage of the black color paste can be 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, etc., which are not listed one by one; the weight percentage of the second dispersion resin can be 5 parts, 6 parts, 8 parts, 10 parts, 12 parts, 15 parts, 16 parts, 18 parts, 20 parts, etc., which are not listed one by one; the weight percentage of the photocurable monomer can be 8 parts, 9 parts, 10 parts, 11 parts, 12 parts, etc., which are not listed one by one; the weight percentage of the second organic solvent can be 20 parts, 25 parts, 30 parts, 35 parts, 40 parts, 45 parts, 50 parts, etc., which are not listed one by one.

[0040] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0041] 1) The present invention can remove impurities and pollutants on the surface of the pigment by acid treatment modification of the black organic pigment, and at the same time can change the surface charge and hydrophilicity of the pigment particles, increase the hydrophilicity of the pigment, and thus improve its dispersibility in the aqueous phase. In addition, after the acid treatment, some functional groups (such as carboxyl, hydroxyl, etc.) may be formed on the surface of the pigment, and these functional groups can interact with the functional groups in the acrylic polymer dispersant to enhance the adsorption capacity of the dispersant. By changing the surface properties of the pigment, the acid treatment can improve the stability of the pigment in the dispersion medium, reduce precipitation and aggregation, and achieve a no-residue effect.

[0042] 2) When screening dispersants, the steric hindrance dispersion mechanism was mainly used. Therefore, some dispersants have large particle sizes after dispersion, or cannot disperse the pigments after reacting with the pigments to obtain stable color pastes. By combining steric hindrance, electrostatic stabilization, adsorption of pigment affinity groups, and wetting and penetration, acrylic polymer dispersants can effectively stabilize black pigment particles, prevent them from agglomerating and precipitating, and thus achieve good dispersion effects.

[0043] 3) The present invention adjusts the grinding process: through multi-step grinding (0.3-0.4nm zirconia bead grinding + 0.1nm zirconia bead grinding), and by adjusting the grinding time, grinding ball particle size, grinding speed, etc., the low particle size and excellent stability of the color paste are controlled. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] The accompanying drawings are incorporated in and constitute a part of this specification and, together with the description, serve to explain the principles of the present invention.

[0045] Figure 1 A patterned film made from the photoresist prepared in Examples 1 to 4;

[0046] Figure 2The patterned film is made from the photoresist prepared in Comparative Examples 7 to 13. DETAILED DESCRIPTION

[0047] Here, exemplary embodiments will be described in detail, and the embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are only examples consistent with some aspects of the present invention described in detail in the appended claims.

[0048] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and embodiments.

[0049] First, prepare a black color paste according to the weight proportions of the raw materials in Table 1 below, as follows:

[0050] Table 1

[0051]

[0052]

[0053] Preparation Example 1

[0054] This preparation example provides a residue-free black color paste (S-1) for BPDL, comprising the following raw materials in parts by weight: 10 parts of a black modified organic pigment, 8 parts of a first dispersing resin, 6 parts of a dispersant, and 73 parts of a first organic solvent;

[0055] Among them: the black organic pigment is BASF L0080; the added amount of the acid containing an acidic group is 5% of the weight of the black organic pigment, and is a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the weight ratio of the two is 1.5:1; the first dispersing resin is Lisennoko SP-DW-W1002, and the double bond equivalent is 1500meq / g; the dispersant is EFKA PU4050; the first organic solvent is propylene glycol methyl ether acetate.

[0056] The above-mentioned black modified organic pigment (obtained by acid-treating the black organic pigment with the above-mentioned acid containing an acid group), the first dispersing resin, and the dispersant are added to the first organic solvent in specific weight portions and mixed, and then ground twice to obtain a black color paste (S-1); wherein the grinding includes: first using 0.3-0.4nm zirconium oxide beads to grind for 3-5 hours to obtain a dispersion with a particle size of less than 300nm; and then using 0.1nm zirconium oxide beads to grind in a dispersion bead mill for 10-14 hours to obtain a black dispersed color paste (S-1) with a particle size of less than 100nm.

[0057] Preparation Example 2

[0058] Based on Preparation Example 1, this Preparation Example provides a residue-free black color paste (S-2) for BPDL, which is different from Preparation Example 1 in that the weight portion of the black modified organic pigment is 20 parts, the acid containing an acidic group is a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the weight ratio of the two is 2:1.

[0059] Preparation Example 3

[0060] Based on Preparation Example 1, this Preparation Example provides a residue-free black color paste (S-3) for BPDL, which is different from Preparation Example 1 in that the weight portion of the black modified organic pigment is 20 parts, the acid containing an acidic group is a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the weight ratio of the two is 2.5:1.

[0061] Preparation Example 4

[0062] Based on Preparation Example 1, this Preparation Example provides a residue-free black color paste (S-4) for BPDL, which is different from Preparation Example 1 in that the weight portion of the black modified organic pigment is 25 parts, the acid containing an acidic group is a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the weight ratio of the two is 1.5:1.

[0063] Comparative Example 1

[0064] This comparative example provides a black color paste (D-1), which is based on Preparation Example 2, but differs from Preparation Example 2 in that the acid containing an acidic group is 2-phenylpropionic acid.

[0065] Comparative Example 2

[0066] This comparative example provides a black color paste (D-2), which is based on Preparation Example 2, but differs from Preparation Example 2 in that the acid containing an acidic group is 2-hydroxypropionic acid.

[0067] Comparative Example 3

[0068] This comparative example provides a black color paste (D-3), which is based on Preparation Example 2, but differs from Preparation Example 2 in that: there is no acid containing an acidic group in the raw materials.

[0069] Comparative Example 4

[0070] This comparative example provides a black color paste (D-4), which is based on Preparation Example 2 and differs from Preparation Example 2 in that: the amount of acid containing an acidic group added is 15% of the weight of the black organic pigment, and is a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the weight ratio of the two is 1.5:1; and, no dispersant is contained.

[0071] Comparative Example 5

[0072] This comparative example provides a black color paste (D-5), which is based on Preparation Example 2 and differs from Preparation Example 2 in that: the amount of acid containing an acidic group added is 15% of the weight of the black organic pigment, and is a mixture of 2-hydroxypropionic acid and 2-phenylpropionic acid, and the weight ratio of the two is 1.5:1; and the amount of dispersant added is 15 parts.

[0073] Comparative Example 6

[0074] This comparative example provides a black color paste (D-6), which is based on Preparation Example 2, but different from Preparation Example 2 in that: EFKA 4703 (amine value 56 mg KOH / g) is used as the dispersant.

[0075] Based on the black color paste prepared in the above preparation examples and comparative examples, a black photoresist is prepared according to the mass fractions of each raw material in Table 2 below, and the preparation of the black photoresist specifically includes: adding the raw materials according to the corresponding weight fractions into a reaction container, mixing and stirring with a stirrer, and obtaining a black photoresist. Among them, the black color paste is 30 to 50 parts, the second dispersion resin is 5 to 20 parts, the photocurable monomer is 8 to 12 parts, the photoinitiator is 3 to 5 parts, and the second organic solvent is 20 to 50 parts.

[0076] Table 2

[0077]

[0078]

[0079] Example 1

[0080] This embodiment provides a black photoresist (P-1), and the raw materials are weighed according to the corresponding weight portions: 40 parts of black color paste (S-1), 6 parts of second dispersed resin, 10 parts of photocurable monomer, 4 parts of photoinitiator, and 40 parts of second organic solvent.

[0081] The above raw materials are added into a reaction container, and mixed and stirred by a stirrer to obtain a black photoresist (P-1). The black color paste is the black color paste (S-1) prepared in the above Preparation Example 1; the second dispersion resin is SP-W2000, and the epoxy equivalent is 800; the photocurable monomer is dipentaerythritol di(meth)acrylate; the photoinitiator is OXE-1; and the second organic solvent is propylene glycol methyl ether acetate.

[0082] Example 2

[0083] Based on Example 1, this example provides a black photoresist (P-2), which is different from Example 1 in that the black color paste is the black color paste (S-2) prepared in the above-mentioned Preparation Example 2, and the weight proportion of the second dispersed resin is 10 parts.

[0084] Example 3

[0085] Based on Example 1, this example provides a black photoresist (P-3), which is different from Example 1 in that the black color paste is the black color paste (S-3) prepared in the above-mentioned Preparation Example 3, with a weight portion of 30 parts, and the weight portion of the second dispersed resin is 15 parts.

[0086] Example 4

[0087] Based on Example 1, this example provides a black photoresist (P-4), which is different from Example 1 in that the black color paste is the black color paste (S-4) prepared in the above-mentioned Preparation Example 4, with a weight portion of 50 parts, and the weight portion of the second dispersed resin is 20 parts.

[0088] Comparative Example 7

[0089] Based on Example 1, this comparative example provides a black photoresist (P-5), which is different from Example 1 in that the black color paste is the black color paste (D-1) prepared in the comparative example 1 above.

[0090] Comparative Example 8

[0091] Based on Example 1, this comparative example provides a black photoresist (P-6), which is different from Example 1 in that the black color paste is the black color paste (D-2) prepared in the comparative example 2 above.

[0092] Comparative Example 9

[0093] Based on Example 1, this comparative example provides a black photoresist (P-7), which is different from Example 1 in that the black color paste is the black color paste (D-3) prepared in the comparative example 3 above.

[0094] Comparative Example 10

[0095] Based on Example 1, this comparative example provides a black photoresist (P-8), which is different from Example 1 in that the black color paste is the black color paste (D-4) prepared in the comparative example 4 above.

[0096] Comparative Example 11

[0097] Based on Example 1, this comparative example provides a black photoresist (P-9), which is different from Example 1 in that the black color paste is the black color paste (D-5) prepared in the comparative example 5 above.

[0098] Comparative Example 12

[0099] Based on Example 1, this comparative example provides a black photoresist (P-10), which is different from Example 1 in that the black color paste is the black color paste (D-6) prepared in the above comparative example 6.

[0100] Comparative Example 13

[0101] Based on Example 1, this comparative example provides a black photoresist (P-11), which is different from Example 1 in that the second dispersed resin is SP-DW-W1001 and has an epoxy equivalent of 1500.

[0102] The performance tests of the black photoresists prepared in the above-mentioned Examples 1 to 4 and Comparative Examples 7 to 13 were conducted, specifically including the following aspects:

[0103] (1) Particle size: Use a Calvin particle size analyzer to test the Z value (average particle size) and Dn50 (median particle size) of the color paste after solvent dilution.

[0104] (2) Viscosity: Use a rotational viscometer to test the viscosity of the color paste at 25°C.

[0105] (3) Stability: The particle size and viscosity of the test paste were tested after standing in a 45°C oven for 7 days. When the △Z value and △Dn50 value were both less than 5%, it indicated that the stability was excellent.

[0106] (4) Residue test: The BPDL was patterned and prepared using the following photolithography process conditions, and the residue was tested.

[0107] Spin the black photoresist onto the substrate at a spin coating speed of 250 rpm, vacuum desolventize for 120 s, soft bake at 120 °C for 120 s, use the Line and Hole MASK, and expose at 365 nm I-line at 100 mj / cm 2 , developed with 2.38% TMAH (alkaline developer) for 60 seconds, and post-baked at 250°C for 1 hour to obtain a patterned film. The residue in the hole was evaluated using a fluorescent microscope (blue light (470 nm), reflection mode, 500 times).

[0108] (5) Resolution test: Use a scanning electron microscope to inspect the photoresist pattern, observe and measure the minimum line width and pattern clarity, and evaluate its resolution capability at a specific wavelength.

[0109] After testing, the performance results of the compositions in Examples 1 to 4 and Comparative Examples 7 to 13 are shown in Table 3 below:

[0110] Table 3

[0111]

[0112]

[0113] In summary, from the data in Table 3 and the test experiments, it can be seen that only when the black photoresist contains a specific ratio of black color paste, a second dispersion resin, a photocurable monomer, a photoinitiator and a second organic solvent, and the black color paste used is composed of a certain weight percentage of specific raw materials, the color paste particle size, viscosity and stability are excellent, and the obtained patterned film has no residue, such as Figure 1 shown.

[0114] In contrast, the resolution of the corresponding compositions of Comparative Examples 7 to 13 can still meet the requirements, but the patterned films prepared using the corresponding compositions, such as Figure 2 As shown, there are residues in the pores, which leads to a decrease in the density of the film, thereby affecting its mechanical properties, thermal stability and chemical stability; in addition, it will also affect the optical properties of the film, such as transmittance and reflectivity, causing the product to be scrapped and unusable.

[0115] Specifically:

[0116] In Comparative Example 7, the black color paste used therein is the black color paste (D-1) prepared in Comparative Example 1, i.e., the acid containing an acidic group is 2-phenylpropionic acid alone; in Comparative Example 8, the black color paste used therein is the black color paste (D-2) prepared in Comparative Example 2, i.e., the acid containing an acidic group is 2-hydroxypropionic acid alone. That is, the acid containing an acidic group in Comparative Examples 7 and 8 is added in a single manner, and although the particle size and viscosity of the obtained composition are not much different from those of Examples 1 to 4, the stability does not meet the requirements (the ΔZ value and ΔDn50 value are significantly greater than 5%, indicating that the stability of the composition is poor).

[0117] As for Comparative Example 9, the black color paste used therein is the black color paste (D-3) prepared in Comparative Example 3. Since the black organic pigment is not subjected to acid treatment, it is impossible to provide active sites for the adsorption of the dispersant, thereby reducing the adsorption efficiency and dispersion effect of the dispersant, resulting in an increase in particle size, easy agglomeration, increased viscosity, and stability that does not meet the requirements.

[0118] As for Comparative Example 10, the black color paste used therein is the black color paste (D-4) prepared in Comparative Example 4. Since no dispersant is added, the organic pigment cannot be dispersed, resulting in extremely large particle size (Z value is as high as 436.21nm, Dn50 is as high as 246.33nm), increased viscosity, and stability that cannot meet the requirements.

[0119] As for Comparative Example 11, the black color paste used therein is the black color paste (D-5) prepared in Comparative Example 5, that is, the amount of dispersant added is too much, resulting in a smaller particle size and better stability; but at the same time, if too much dispersant is added, the amine value will increase and the alkalinity will be enhanced. In the process of alkaline washing with alkaline developer, it is not easy to wash away the unexposed part, resulting in residual photoresist, which will inevitably affect the quality of the imaging pattern.

[0120] As for Comparative Example 12, the black color paste used therein is the black color paste (D-6) prepared in Comparative Example 6, and the dispersant is EFKA4703 (amine value 56 mg KOH / g, exceeding the aforementioned numerical range of 10 to 20 mg KOH / g), which results in an increase in particle size, easy agglomeration, increased viscosity, and stability that does not meet the requirements.

[0121] As for Comparative Example 13, the black colorant used is the black colorant (S-1) prepared in Preparation Example 1, and the second dispersing resin is SP-DW-W1001, and the epoxy equivalent is 1500meq / g (too large, exceeding the aforementioned numerical range of 600 to 800meq / g), resulting in photoresist residue, which will inevitably affect the quality of the imaging pattern.

[0122] The above description is only a specific embodiment of the present invention, so that those skilled in the art can understand or implement the present invention. Various modifications to these embodiments will be apparent to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention.

[0123] It should be understood that the present invention is not limited to what has been described above and that various modifications and changes may be made without departing from its scope. The scope of the present invention is limited only by the appended claims.

Claims

1. A residue-free black color paste for BPDL, characterized in that: The invention comprises the following raw materials in parts by weight: 10 to 25 parts of black modified organic pigment, 3 to 10 parts of first dispersing resin, 3 to 10 parts of dispersant and 70 to 84 parts of first organic solvent; the black modified organic pigment is obtained by subjecting the black organic pigment to acid treatment.

2. The residue-free black color paste for BPDL according to claim 1, characterized in that: The acid used in the acid treatment is an acid containing an acidic group, and the acid containing an acidic group includes an organic acid and / or an inorganic acid.

3. The residue-free black color paste for BPDL according to claim 2, characterized in that: The added amount of the acid containing an acidic group is 3% to 10% of the weight of the black organic pigment.

4. The residue-free black color paste for BPDL according to claim 1, characterized in that: The first dispersing resin has a double bond equivalent of 1000 to 1500 meq / g, an acid value of 20 to 100 mgKOH / g, a molecular weight of 5000 to 15000, and a PDI value of less than 3.

5. The residue-free black color paste for BPDL according to claim 1, characterized in that: The dispersant is at least one of anionic dispersants, cationic dispersants, nonionic dispersants and polymer dispersants.

6. The residue-free black color paste for BPDL according to claim 1, characterized in that: The first organic solvent is at least one of propylene glycol monomethyl ether, propylene glycol methyl ether, ethylene glycol methyl ether acetate, ethylene glycol dimethyl ether and propylene glycol monomethyl ether acetate.

7. A method for preparing a residue-free black color paste for BPDL as claimed in any one of claims 1 to 6, characterized in that: The black modified organic pigment, the first dispersing resin and the dispersant are added into the first organic solvent in specific weight proportions, mixed and ground to obtain the pigment.

8. The method for preparing a residue-free black color paste for BPDL according to claim 7, characterized in that: The grinding is specifically: First, use 0.3-0.4 nm zirconium oxide beads to grind for 3-5 hours to obtain a dispersion with a particle size of less than 300 nm; then use 0.1 nm zirconium oxide beads to grind for 10-14 hours to obtain a black color paste with a particle size of less than 100 nm.

9. A black photoresist based on the residue-free black color paste for BPDL according to any one of claims 1 to 6, characterized in that: The invention comprises the following components in parts by weight: 30 to 50 parts of black color paste, 5 to 20 parts of second dispersion resin, 8 to 12 parts of photocurable monomer, 3 to 5 parts of photoinitiator and 20 to 50 parts of second organic solvent.

10. The black photoresist according to claim 9, characterized in that: The double bond equivalent of the second dispersing resin is 600 to 800 meq / g.

Images