Preparation method of red organic pigment for liquid crystal color filter material

Abstract

The invention discloses a preparation method of a red organic pigment for a liquid crystal color filter material, which comprises the following steps: adding a hyperbranched polymer nano dispersant into ethyl acetate, and adding a pigment red 122 crude product and calcium chloride to obtain mixed slurry; adding the mixed slurry into a ball mill for grinding to obtain ground slurry; transferring the ground slurry into a dodecylamine polyoxyethylene ether aqueous solution, stirring, preserving heat, and filtering to obtain surface modified slurry; adding the surface modified slurry into a DMF (Dimethyl Formamide) solution containing a hyperbranched polymer nano dispersant, carrying out ultrasonic treatment, and filtering to obtain final slurry; and drying to obtain the product. By improving the processing technology of the pigment, pigment particles are refined to nanoscale, and the dispersion stability and fluidity of the pigment are improved. The prepared red organic pigment is uniform in particle size distribution, has high color purity and good optical performance, and is suitable for a color filter of a liquid crystal display.

Description

Technical Field

[0001] The invention relates to the technical field of pigments, and in particular to a method for preparing a red organic pigment used in liquid crystal color filter materials. Background Art

[0002] Color liquid crystal display (LCD) is one of the most common display devices today, and is widely used in various electronic products such as televisions, computers, and mobile phones. The display principle of LCD is mainly to achieve the color display of the image through the combination of color filter (CF) and liquid crystal material. The color filter is usually composed of red, green, and blue primary color sub-pixels, and each color sub-pixel forms a corresponding color through the backlight provided by the light source. Specifically, the backlight passes through each pixel unit of the color filter, and the light transmission is controlled by the opening and closing of the liquid crystal in each of the red, green, and blue sub-pixels, thereby generating a complete color image.

[0003] The red, green and blue colors in color filters are mainly transmitted through different organic pigment layers to achieve specific wavelengths of light, providing the required color performance. Organic pigments have high color saturation and good light resistance, so they are widely used in displays. In color filters, the use of pigments usually requires high color purity, good transparency, and the ability to maintain stable color under long-term illumination. Commonly used red organic pigments include quinacridone (Quinacridone), diketopyrrolopyrrole (DPP), etc. These pigments have high color vividness and excellent light resistance, and are an important source of materials for color filters.

[0004] During the coating process of color filters, organic pigments need to be attached to the filter substrate with extremely high dispersion uniformity to ensure the consistency of their color rendering effect. The dispersibility of pigment particles directly affects the transparency and durability of the filter. In traditional preparation processes, pigments usually need to be nano-sized through ultrafine grinding, ultrasonic dispersion, etc., but these methods still have limitations in terms of the uniformity of pigment particle distribution, size control accuracy, and dispersion stability. In addition, organic pigments have poor storage stability in the dispersion medium and are often prone to aggregation or sedimentation, resulting in the formation of an uneven coloring layer during the coating process of the filter. Summary of the invention

[0005] Based on the problems existing in the background technology, the present invention provides a method for preparing a red organic pigment for liquid crystal color filter materials, by improving the processing technology of the pigment, the pigment particles are refined to the nanometer level, and the dispersion stability and fluidity of the pigment are improved through a specific dispersion treatment. The prepared red organic pigment has a uniform particle size distribution, high color purity and good optical properties, and is suitable for color filters of liquid crystal displays.

[0006] The present invention is implemented by the following technical solutions:

[0007] A method for preparing a red organic pigment for a liquid crystal color filter material comprises the following steps:

[0008] S1. The hyperbranched polymer nanodispersant was added to ethyl acetate, and crude Pigment Red 122 and calcium chloride were added, and mixed to obtain a mixed slurry;

[0009] S2. The mixed slurry is added to a ball mill and wet-ground to obtain a ground slurry;

[0010] S3. The ground slurry was transferred to an aqueous solution of polyoxyethylene dodecylamine ether, stirred and heated, and filtered to obtain a surface-modified slurry;

[0011] S4. adding the surface modified slurry to a DMF solution containing a hyperbranched polymer nanodispersant, ultrasonically treating, and filtering to obtain a final slurry;

[0012] S5. Dry the final slurry to obtain a red organic pigment for liquid crystal color filter material.

[0013] Furthermore, in step S1, the hyperbranched polymer nanodispersant is a hyperbranched polyacrylamide-methyl acrylate copolymer.

[0014] Furthermore, the preparation method of the hyperbranched polyacrylamide-methyl acrylate copolymer is specifically as follows: acrylamide and methyl methacrylate are added to a DMF solution, ethylene glycol dimethacrylate is added, and the mixture is stirred evenly; under nitrogen protection, the mixture is heated to 60° C., azobisisobutyronitrile is added in sequence to initiate a polymerization reaction, and the reaction is stirred for 8-10 hours. After the reaction is completed, the reaction solution is slowly dripped into ice ethanol for precipitation, washed, and dried to obtain the hyperbranched polyacrylamide-methyl acrylate copolymer.

[0015] Furthermore, the mass ratio of acrylamide to methyl methacrylate is 1:(2-5); the amount of ethylene glycol dimethacrylate accounts for 4-6% of the total mass of acrylamide; and the amount of azobisisobutyronitrile accounts for 0.1-1% of the total mass of acrylamide and methyl methacrylate.

[0016] Furthermore, the raw material components in step S1 are specifically composed of 2-5 parts by weight of hyperbranched polymer nanodispersant, 80-120 parts of crude pigment red 122, 100-200 parts of calcium chloride, and 25-40 parts of ethyl acetate.

[0017] Furthermore, in step S2, the wet grinding uses zirconium oxide beads with a diameter of 0.5-1 mm as grinding media, the rotation speed of the ball mill is 800-1000 rpm, the grinding time is 10-12 h, and the grinding temperature is lower than 40°C.

[0018] Furthermore, in step S3, the mass fraction of the dodecylamine polyoxyethylene ether aqueous solution is 2-3%; the insulation temperature is 50-60° C., and the time is 3-4 hours.

[0019] Furthermore, in step S3, the mass ratio of the ground slurry to the aqueous solution of dodecylamine polyoxyethylene ether is 1:(1-2).

[0020] Furthermore, in step S4, the mass fraction of the hyperbranched polymer nanodispersant in the DMF solution containing the hyperbranched polymer nanodispersant is 2-3%, and the ultrasonic treatment is performed for 30-60 minutes.

[0021] Furthermore, in step S4, the mass ratio of the surface modified slurry to the DMF solution containing the hyperbranched polymer nanodispersant is 1:(1.5-3).

[0022] Beneficial effects of the present invention:

[0023] 1. The dispersant used in the present invention is a hyperbranched polymer, which has a highly branched structure, so that it can be effectively dispersed in the liquid phase. This helps to improve the dispersion state of the pigment in the solution, prevent the pigment from aggregating or precipitating, and thus improve the stability and uniformity of the pigment. Especially in liquid crystal display applications, uniform dispersion of the pigment is the key to achieving high-quality color.

[0024] 2. Through surface modification, dodecylamine polyoxyethylene ether is added to the pigment surface to improve the compatibility of the pigment with the liquid crystal material. This is crucial to ensure the uniformity and stability of the liquid crystal color filter material, especially in liquid crystal displays, where good compatibility between the pigment and the substrate effectively improves the display effect. In addition, surface modification helps the functionalization of the pigment, improving its optical properties, chemical resistance, heat resistance, etc.

[0025] 3. Adding hyperbranched polymer nanodispersants to the surface-modified slurry further enhances the dispersion stability of the pigment. This two-stage dispersant application can ensure the long-term stability of the pigment in the liquid crystal color filter material and avoid the reaggregation of pigment particles. Using hyperbranched polymers as dispersants can effectively improve the optical effect of the pigment, enhance color purity, reduce light scattering and shielding effects between particles, and thus enhance the brightness and color contrast of the liquid crystal color filter material.

[0026] 4. The red organic pigment prepared by the method of the present invention has a fine particle size and good dispersion, and after surface modification, it can improve the compatibility with the liquid crystal display substrate, further improve its optical properties, and ensure the accuracy and vividness of the color. In the liquid crystal color filter application, this red organic pigment can effectively adjust the light transmittance and light reflection, and provide more stable and accurate colors. The use of surface modification and hyperbranched polymers makes the pigment have stronger chemical resistance and light resistance, especially in the liquid crystal display environment, the pigment needs to withstand a variety of chemical media and ultraviolet light irradiation. Such a pigment can maintain its color stability and extend its service life. DETAILED DESCRIPTION

[0027] The technical solution of the present invention is further described in detail below in conjunction with specific embodiments, but the protection scope of the present invention is not limited to the following embodiments.

[0028] Example 1

[0029] A method for preparing a red organic pigment for a liquid crystal color filter material comprises the following steps:

[0030] S1. Preparation of hyperbranched polymer nanodispersant: 10 parts of acrylamide and 30 parts of methyl methacrylate were added to a DMF solution, and 1 part of ethylene glycol dimethacrylate was added and stirred evenly; under nitrogen protection, the mixture was heated to 60°C, and 0.33 parts of azobisisobutyronitrile were added in sequence to initiate polymerization reaction, and the reaction was stirred for 8-10 hours. After the reaction was completed, the reaction solution was slowly dripped into ice ethanol for precipitation and washing, and then dried to obtain a hyperbranched polyacrylamide-methyl acrylate copolymer;

[0031] S2. 3 parts of the hyperbranched polymer nanodispersant were added to 25 parts of ethyl acetate, and 100 parts of crude Pigment Red 122 and 150 parts of calcium chloride were added, and mixed to obtain a mixed slurry;

[0032] S3. The mixed slurry was added to a ball mill, using zirconia beads with a diameter of 0.5-1 mm as the grinding medium, the ball mill speed was 800 rpm, the grinding time was 12 h, the grinding temperature was below 40 ° C, wet grinding, and the ground slurry was obtained;

[0033] S4. The ground slurry was transferred to a 2% aqueous solution of dodecylamine polyoxyethylene ether by mass, the mass ratio of the ground slurry to the aqueous solution of dodecylamine polyoxyethylene ether was 1:1, stirred and kept warm at 60°C for 3h, filtered, and a surface-modified slurry was obtained;

[0034] S5. The surface-modified slurry was added to a DMF solution containing a hyperbranched polymer nanodispersant having a mass fraction of 2%, the mass ratio of the surface-modified slurry to the DMF solution containing the hyperbranched polymer nanodispersant being 1:2, ultrasonically treated for 30 min, and filtered to obtain a final slurry;

[0035] S6. Dry the final slurry to obtain a red organic pigment for liquid crystal color filter material.

[0036] Example 2

[0037] The difference between this embodiment and embodiment 1 is that in step S2, 5 parts of hyperbranched polymer nanodispersant are added to 25 parts of ethyl acetate, and then 90 parts of crude pigment red 122 and 150 parts of calcium chloride are added and mixed uniformly to obtain a mixed slurry; the remaining steps are the same as in embodiment 1.

[0038] Comparative Example 1

[0039] The dispersant used was WinSperse 3200 (Weibosi New Materials (Weifang) Co., Ltd.);

[0040] The specific preparation steps are as follows:

[0041] S1. 3 parts of dispersant Wi nSperse 3200 were added to 25 parts of ethyl acetate, and 100 parts of crude pigment red 122 and 150 parts of calcium chloride were added, and mixed to obtain a mixed slurry;

[0042] S2. The mixed slurry was added to a ball mill, using zirconia beads with a diameter of 0.5-1 mm as the grinding medium, the speed of the ball mill was 800 rpm, the grinding time was 12 h, the grinding temperature was below 40 ° C, wet grinding, and the ground slurry was obtained;

[0043] S3. The ground slurry was transferred to a 2% aqueous solution of dodecylamine polyoxyethylene ether by mass, the mass ratio of the ground slurry to the aqueous solution of dodecylamine polyoxyethylene ether was 1:1, stirred and kept warm at 60°C for 3h, filtered, and a surface-modified slurry was obtained;

[0044] S4. Dry the final slurry to obtain a red organic pigment for liquid crystal color filter material.

[0045] Comparative Example 2

[0046] The difference between this comparative example and Example 1 is that the dispersant used is polyacrylamide-methyl acrylate copolymer, and the preparation method thereof is as follows: 30 parts of acrylamide and 10 parts of methyl methacrylate are added to 50 parts of DMF solution, 1 part of ethylene glycol dimethacrylate is added, and the mixture is stirred evenly; under nitrogen protection, the mixture is heated to 60° C., 0.33 parts of azobisisobutyronitrile are added in sequence to initiate polymerization reaction, the mixture is stirred for reaction for 8-10 hours, and the mixture is cooled to room temperature. After the reaction is completed, the reaction solution is slowly dripped into ice ethanol for precipitation, washed, and dried to obtain polyacrylamide-methyl acrylate copolymer; the remaining steps are the same as those in Example 1.

[0047] Comparative Example 3

[0048] The difference between this comparative example and Example 1 is that the preparation steps do not include step S5, the modified slurry is prepared in step S4 and directly freeze-dried; the remaining steps are the same as in Example 1.

[0049] Application Example 1

[0050] The pigment of Example 1 is prepared into a red color paste; the specific method is: 5.7 g of red organic pigment, 4.5 g of grinding resin BM52 (produced by Shanghai Bolier Chemical), 2.3 g of grinding aid WinSperse3030 (Weibos New Materials (Weifang) Co., Ltd.), 25.5 g of propylene glycol methyl ether acetate, add 0.1 mm zirconium balls into a grinding jar, use a Miqi double planetary power ball mill to mix and disperse for 24 hours to obtain a red color paste.

[0051] Application Example 2

[0052] The pigment obtained in Example 2 of the same weight is used to replace the pigment in Example 1 used in Application Example 1, and the remaining components, component amounts and operating process are the same as those in Application Example 1.

[0053] Comparative application example 1

[0054] The pigment obtained in Comparative Example 1 of equal weight is used to replace the pigment of Example 1 used in Application Example 1, and the remaining components, component amounts and operating process are the same as those in Application Example 1.

[0055] Comparative Application Example 2

[0056] The pigment obtained in Comparative Example 2 of equal weight is used to replace the pigment of Example 1 used in Application Example 1, and the remaining components, component amounts and operating process are the same as those in Application Example 1.

[0057] Comparative Application Example 3

[0058] The pigment obtained in Comparative Example 3 of equal weight is used to replace the pigment of Example 1 used in Application Example 1, and the remaining components, component amounts and operating process are the same as those in Application Example 1.

[0059] Comparative Application Example 4

[0060] An equal weight of untreated commercially available Pigment Red 122 was used to replace the pigment of Example 1 used in Application Example 1, and the remaining components, component amounts and operating procedures were the same as those in Application Example 1.

[0061] The red color paste prepared by corresponding application examples 1-2 and comparative application examples 1-3 was subjected to performance testing.

[0062] Particle size test

[0063] The particle size analyzer 90P lus was used to test the average particle size and particle size distribution of the red color paste obtained in the application example and the comparative application example.

[0064] Viscosity test and dispersion stability test

[0065] The red color paste prepared in Application Examples 1-2 and Comparative Application Examples 1-3 was allowed to stand at room temperature for 1 day, samples were taken, and the initial viscosity was tested using a viscometer DV2T; the remaining red color paste was allowed to stand at 40°C for 7 days, samples were taken, and the 7-day viscosity was tested using a viscometer DV2T.

[0066] Chemical resistance

[0067] The red color paste obtained in the application example and the comparative application example was formed into a coating film on a 6cm×6cm glass sheet by a spin coater, pre-baked at 120°C for 3 minutes, and placed in an oven at 230°C for 30 minutes.

[0068] The prepared smear was immersed in a propylene glycol monomethyl ether acetate (PGMEA) solvent at 60° C. for 10 minutes, and the color change before and after the evaluation was observed. Here, the color change was calculated using the following equation, and the values ​​calculated using the equation are shown in Table 1 below.

[0069] ΔEab*=[(ΔL*) 2 +(Δa*) 2 +(Δb*) 2 ] 1 / 2

[0070] Wherein ΔL*, Δa*, Δb* represent the color change defined by L*, a* and b* observed using a three-dimensional colorimeter.

[0071] Evaluation Criteria

[0072] ○: Good chemical resistance (no pattern change, Δ(Eab*) less than 3.0)

[0073] △: Average chemical resistance (slight pattern change, Δ(Eab*) is 3.0 to less than 5.0)

[0074] ×: Poor chemical resistance (pattern change, Δ(Eab*) is 5.0 or more)

[0075] Smear contrast test

[0076] The smear is measured by a contrast tester (Japan Keban Electric CT-1) to measure the ratio of the brightness when the polarizer is in an orthogonal position to the brightness when the polarizer is in a parallel position, which is the contrast. Assuming that the contrast obtained by the comparative application example 4 is 100, the contrast values ​​obtained by the tests of other application examples and comparative application examples are compared with it, and the contrast data shown in Table 1 are obtained.

[0077] All test results are shown in Table 1.

[0078] Table 1

[0079]

[0080] As can be seen from the data in Table 1, the red color paste prepared by using Examples 1 and 2 of the present invention has a smaller average particle size, a narrower particle size distribution, and better storage stability. The prepared smear has good chemical resistance, and the contrast is close to that of the commercially available Pigment Red 122, which has obvious advantages. The red organic pigment prepared by the present invention can be used for the preparation of colorants for red pixels of liquid crystal color filter materials. In the preparation of Comparative Example 1, the dispersant Wi nSperse 3200 was used, and the aqueous solution of dodecylamine polyoxyethylene ether was directly filtered and dried after treatment during the preparation process, and the dispersant was no longer used for secondary treatment. The properties of the red color paste finally obtained were reduced. In the preparation of Comparative Example 2, polyacrylamide-methyl acrylate copolymer was used as a dispersant, and the amount of polyacrylamide and methyl methacrylate was adjusted. The copolymer finally prepared was more inclined to a linear structure rather than a hyperbranched structure, and the increase in the amount of acrylamide resulted in an enhanced hydrophilicity of the copolymer, which was not conducive to the improvement of the dispersibility of the organic pigment. Therefore, the performance of the final color paste was also reduced. In Comparative Example 3, after wet grinding, the mixture was treated with an aqueous solution of dodecylamine polyoxyethylene ether and then directly filtered and dried without using a dispersant for secondary treatment. The dispersion stability of the red color paste was reduced and the color contrast was slightly reduced.

[0081] In one embodiment, the method for preparing a red organic pigment for a liquid crystal color filter material, after obtaining the red organic pigment for a liquid crystal color filter material, further comprises:

[0082] S6. Performing a compliance test on the obtained red organic pigment for liquid crystal color filter materials. When the test condition parameters reflect that the compliance test is unqualified, a preparation process problem tracing model is adaptively formulated based on the test condition parameters, and the preparation process (including at least: the above steps S1 to S5) is traced based on the preparation process problem tracing model, and the traced problems are solved online;

[0083] Among them, in S6, the adaptive formulation of the production process problem tracing model based on the detection situation parameters includes:

[0084] S611, extracting features of detection condition parameters to obtain multiple parameter features;

[0085] In S611, the detection condition parameters are various result parameters of the obtained red organic pigment for liquid crystal color filter material subjected to the standard detection; the standard index is set in advance, and the monitoring condition parameters are generated based on the difference relationship between the detection result and the standard index; the extracted parameter features are the relevant data features of the detection condition parameters;

[0086] S612, mapping each parameter feature with the problem graph to obtain a plurality of mapping problems; wherein the mapping problems are problems corresponding to the root nodes and branch nodes of the tree data structure in which all leaf nodes are occupied by each parameter feature in the problem graph;

[0087] In S612, there are multiple tree data structures in the problem map. In a tree data result, the root node is the beginning of a detection process problem. The root node has multiple branches, and the branches have multiple branch nodes. A branch represents the change process of a problem parameter of the detection process problem. The branch nodes connected in sequence are multiple process items of the change process. The terminal of a branch is a leaf node, and the leaf node is a change result of a problem parameter. When the parameter features occupy all the leaf nodes, the problems corresponding to the root nodes and branch nodes of the corresponding tree data structure all need to be traced.

[0088] S613, generating a template based on the problem tracing rule, and generating multiple problem tracing rules according to each mapping problem;

[0089] In S613, the problem tracing rule is a rule for whether there is a mapping problem in the tracing preparation process;

[0090] S614. Based on the tracing rules of each problem, formulate a tracing model for the problem in the preparation process;

[0091] In S614, a preparation process problem tracing model is finally formulated based on each problem tracing rule. When formulating, multiple problem tracing rules can be sorted to form a system working module in which the rules are executed in sequence, which serves as the preparation process problem tracing model;

[0092] In S6, the online solution to the traceability problem includes:

[0093] S621. Conduct knowledge demand analysis on the source tracing problem to obtain multiple knowledge demands;

[0094] In S621, when conducting knowledge demand analysis, it is analyzed what kind of knowledge is needed to solve the traceability acquisition problem, that is, the knowledge demand;

[0095] S622, traverse each knowledge requirement in turn;

[0096] S623, each time during the traversal, analyzing the demand type of the traversed knowledge demand; the demand type is divided into active demand and passive demand;

[0097] In S623, there are two types of knowledge needs: active and passive. Active means that it can be acquired based on knowledge alone; passive means that it needs to be connected with other knowledge to acquire knowledge.

[0098] S624, when the demand type of the knowledge demand is an active demand, acquiring corresponding first target knowledge based on the knowledge demand;

[0099] In S624, the first target knowledge may be in the form of expert experience or the like;

[0100] S625, connecting knowledge requirements whose requirement types are passive requirements to obtain connected knowledge requirements, and acquiring corresponding second target knowledge based on the connected knowledge requirements;

[0101] In S625, similarly, the second target knowledge may be in the form of expert experience, etc.; the second target knowledge may meet all knowledge requirements for connection;

[0102] S626, generating a problem-solving strategy based on the first target knowledge and the second target knowledge;

[0103] In S626, after the first target knowledge and the second target knowledge are acquired, a problem solving strategy is generated based on the first target knowledge and the second target knowledge;

[0104] S627. Based on the problem solving strategy, the traceability problem is solved online.

[0105] In S627, finally, based on the problem solving strategy, the traceability problem is solved online; online means that the system makes corresponding adjustments to the equipment control involved in the preparation process.

[0106] The embodiments of the present invention achieve the following beneficial effects:

[0107] 1. In the prior art, many preparation processes often rely on experience or fixed testing standards to identify and solve problems. However, this embodiment introduces a problem tracing model by adaptively feedback on the compliance test results during the preparation process, which can accurately analyze the specific reasons for each test failure. Compared with the traditional preparation process, when quality is unqualified, an automated problem tracing model can be used for in-depth analysis to fundamentally find problems in the preparation and improve the preparation quality.

[0108] 2. Problem diagnosis in the prior art is often solved through manual detection and manual analysis, which is inefficient and prone to overlooking potential factors. This embodiment extracts detection parameter features, converts the detection results into quantifiable feature data, and then maps these data with the problem map to obtain multiple potential problems, thereby achieving comprehensive and efficient problem tracing. The tree structure of the problem map helps to achieve multi-level and multi-angle analysis, which can more comprehensively identify and analyze the root causes of the problem and avoid missing important factors.

[0109] 3. In the process of problem tracing, this embodiment determines the required knowledge type through knowledge demand analysis, and obtains expert experience or other relevant knowledge according to the demand type. The distinction between active demand and passive demand makes the knowledge acquisition process more accurate and efficient, and can effectively support online adjustment and problem solving.

[0110] 4. By introducing an adaptive problem tracing model, knowledge demand analysis, expert experience and online control adjustment, the automation level, intelligence level and problem-solving efficiency of the red organic pigment preparation process used for liquid crystal color filter materials have been significantly improved. When problems arise, they can be quickly located and solved, thereby reducing quality fluctuations and resource waste in production.

[0111] Finally, it should be noted that the above-mentioned embodiments only express several implementation methods of the present invention and are not intended to limit the invention. For those skilled in the art, any modification, equivalent replacement, improvement, etc. made without departing from the concept of the present invention should be included in the protection scope of the invention. Therefore, the protection scope of the patent of the present invention shall be subject to the attached claims.

Claims

1. A method for preparing a red organic pigment for liquid crystal color filter material, characterized in that: The following steps are involved: S1. The hyperbranched polymer nanodispersant was added to ethyl acetate, and crude Pigment Red 122 and calcium chloride were added, and mixed to obtain a mixed slurry; S2. The mixed slurry is added to a ball mill and wet-ground to obtain a ground slurry; S3. The ground slurry was transferred to an aqueous solution of polyoxyethylene dodecylamine ether, stirred and heated, and filtered to obtain a surface-modified slurry; S4. adding the surface modified slurry to a DMF solution containing a hyperbranched polymer nanodispersant, ultrasonically treating, and filtering to obtain a final slurry; S5. Dry the final slurry to obtain a red organic pigment for liquid crystal color filter material.

2. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: In step S1, the hyperbranched polymer nanodispersant is a hyperbranched polyacrylamide-methyl acrylate copolymer.

3. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 2, characterized in that: The preparation method of the hyperbranched polyacrylamide-methyl acrylate copolymer is specifically as follows: acrylamide and methyl methacrylate are added to a DMF solution, ethylene glycol dimethacrylate is added, and the mixture is stirred evenly; under nitrogen protection, the mixture is heated to 60° C., azobisisobutyronitrile is added in sequence to initiate a polymerization reaction, and the reaction is stirred for 8-10 hours. After the reaction is completed, the reaction solution is slowly dripped into ice ethanol for precipitation, washed, filtered, and dried to obtain the hyperbranched polyacrylamide-methyl acrylate copolymer.

4. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 3, characterized in that: The mass ratio of acrylamide to methyl methacrylate is 1:(2-5); the amount of ethylene glycol dimethacrylate accounts for 4-6% of the total mass of acrylamide; and the amount of azobisisobutyronitrile accounts for 0.1-1% of the total mass of acrylamide and methyl methacrylate.

5. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: The raw material components in step S1 are specifically as follows by weight: 2-5 parts of hyperbranched polymer nanodispersant, 80-120 parts of crude pigment red 122, 100-200 parts of calcium chloride, and 25-40 parts of ethyl acetate.

6. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: In step S2, the wet grinding uses zirconium oxide beads with a diameter of 0.5-1 mm as the grinding medium, the rotation speed of the ball mill is 800-1000 rpm, the grinding time is 10-12 h, and the grinding temperature is lower than 40°C.

7. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: In step S3, the mass fraction of the dodecylamine polyoxyethylene ether aqueous solution is 2-3%; the insulation temperature is 50-60° C., and the time is 3-4 hours.

8. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: The mass ratio of the ground slurry to the aqueous solution of dodecylamine polyoxyethylene ether in step S3 is 1:(1-2).

9. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: In step S4, the mass fraction of the hyperbranched polymer nanodispersant in the DMF solution containing the hyperbranched polymer nanodispersant is 2-3%, and the ultrasonic treatment is performed for 30-60 minutes.

10. The method for preparing a red organic pigment for liquid crystal color filter material according to claim 1, characterized in that: In step S4, the mass ratio of the surface modified slurry to the DMF solution containing the hyperbranched polymer nanodispersant is 1:(1.5-3).

Images