Polymer as well as preparation method and application thereof

Abstract

The invention provides a polymer as well as a preparation method and application thereof. The polymer has a structure as shown in a formula (I), in the formula (I), co represents copolymerization, b represents a block, and R4-C (= S)-S-and-R5 form a chain transfer agent for RAFT (Reversible Addition-Fragmentation Chain Transfer) reaction; each R is independently selected from a hydrogen atom or a methyl group, and R1 is independently selected from 1-4 ethyoxyl repeating units with C1-4 alkyl groups at the tail ends; r2 is independently selected from halogenated or unsubstituted branched chain alkyl; r3 independently comprises alkyl substituted by a cyclic amino group, a chain amino group or a quaternized group thereof; 0 < = n < = 60, 0 < = p < = 60, 40 < = n + p < = 60, and 5 < = m < = 25. The polymer has excellent dispersing capacity on pigments, pigment dispersion liquid containing the polymer can have high pigment content and good storage stability, and when n of the polymer is not 0, the polymer further has high alkali solubility.

Description

Technical Field

[0001] This application relates to the field of pigment dispersion technology, specifically to a polymer, its preparation method, and its application. Background Technology

[0002] A color filter (CF) is an optical filter that precisely selects a small range of wavelengths of light to pass through while reflecting other unwanted wavelengths. A CF consists of color resist layers with different colors. Multiple color resists of the same color are typically formed by a patterning process using a patterned composition of pigment dispersion and photosensitive resin. The dispersion of the pigment in the pigment dispersion greatly affects the filtering effect of the CF.

[0003] Currently, most pigment dispersants used in pigment dispersions are acrylic resins. However, commonly used acrylic resin dispersants do not have a good dispersing effect on pigments, making it difficult for pigment dispersions to achieve high pigment content and good storage stability. Summary of the Invention

[0004] Therefore, embodiments of this application provide a novel pigment dispersant with excellent pigment dispersing ability, so that pigment dispersions / patterned compositions using it can achieve high pigment content and good storage stability, etc.

[0005] Specifically, the first aspect of this application provides a polymer having the structural formula shown in formula (I):

[0006]

[0007] Wherein, co represents copolymerization, b represents block copolymerization, and R4-C(=S)-S- and -R5 constitute the chain transfer agent for RAFT (Reversible Addition-Fragmentation Chain Transfer Polymerization) reaction; each R is independently selected from hydrogen atoms (H) or methyl groups (-CH3), and R1 is independently selected from those with C-terminal groups. 1-4 The alkyl group has 1-4 repeating ethoxy units; R2 is independently selected from halogenated or unsubstituted branched alkyl groups; R3 independently includes alkyl groups substituted with cyclic amino groups, chain amino groups or their quaternary amino groups; 0≤n≤60, 0≤p≤60, and n+p is in the range of 40-60, m is in the range of 5-25.

[0008] In the aforementioned polymers, the repeating units corresponding to the designation 'm' can anchor pigments via the amine groups or quaternary ammonium groups in their side chains, improving the polymer's dispersibility and dispersion stability. The repeating units corresponding to the designation 'p', derived from branched alkyl esters of (meth)acrylate, can increase the polymer's steric hindrance, facilitating the formation of micelles on the pigment surface and further enhancing the polymer's dispersion effect. The repeating units corresponding to the designation 'n', with short-chain ether structures, can enhance the polymer's alkali solubility without affecting its dispersion stability. Furthermore, the polymers are prepared based on the RAFT reaction, exhibiting ordered structures and controllable degrees of polymerization for each repeating unit. The degree of polymerization of each repeating unit meets the aforementioned range requirements, ensuring excellent pigment dispersion capabilities. Pigment dispersions using this polymer as a dispersant can achieve high pigment content and good storage stability, and also exhibit good alkali solubility when 'n' is not 0.

[0009] In this embodiment of the application, the number of carbon atoms in the halogenated or unsubstituted branched alkyl group in R2 is 3-20.

[0010] In some embodiments of this application, R3 comprises C substituted with a dialkylamine group or its quaternary ammonium group. 2-4 Alkyl groups, wherein each alkyl group in the dialkylamino group is independently selected from substituted or unsubstituted C4 groups. 1-6 Alkyl groups. In this case, the amino group or its quaternary ammonium group in R3 has a more stable anchoring effect on the pigment through its nitrogen atom, thus the above polymer has better dispersibility for pigment, and at the same time it is beneficial to improve the solubility / dispersibility of the polymer in ester solvents, ether solvents, ketone solvents, etc.

[0011] In some embodiments of this application, R4 is independently selected from phenyl, dodecyl, or dodecyl groups linked with thioether bonds; R5 is independently selected from -CN, -CH2CN, -C(CH3)2-CN, -CH2-COOH, -CH2-CH2-COOH, -CH(CH3)-COOH, -C(CH3)2-COOH, -C(CH3)(CN)-CH2CH2COOH, or -C(CH3)2-Ph. The RAFT chain transfer agent R4-C(=S)-S-R5 selected from these R4 and R5 provides high controllability for the polymerization of (meth)acrylate monomers, which is beneficial for obtaining polymers with narrow molecular weight distribution and controllable structure.

[0012] In some embodiments of this application, n is an integer between 10 and 35, and p is an integer between 8 and 25. With the combined action of three repeating units of appropriate degree of polymerization, the above-mentioned block polymer can better balance strong pigment dispersibility and good alkali solubility. Therefore, pigment dispersions using the above-mentioned polymer as pigment dispersants can achieve a balance of high pigment content, excellent storage stability, and good alkali solubility.

[0013] In some embodiments of this application, n > 0, p > 0, and n+p is an integer between 40 and 55. The polymer can effectively balance strong pigment dispersibility, good alkali solubility, and good solubility in common organic solvents.

[0014] In some embodiments of this application, m is an integer between 8 and 16. In this case, the polymer not only has a reasonably strong anchoring effect on the pigment, but also has good solubility in organic solvents such as esters, ethers, and ketones.

[0015] In this embodiment, the molecular weight distribution index of the polymer is less than 1.14. This polymer is prepared based on the RAFT reaction and has a narrow molecular weight distribution. Pigment dispersions using this polymer as a pigment dispersant have low viscosity and good dispersion performance.

[0016] The second aspect of this application provides the use of the polymer as described in the first aspect of this application in the preparation of pigment dispersants, pigment dispersions, pigment-containing photosensitive compositions, or color resists.

[0017] A third aspect of this application provides a pigment dispersion comprising a pigment, a pigment dispersant, and a solvent, wherein the pigment dispersant comprises a polymer as described in the first aspect of this application. This pigment dispersion uses a polymer that satisfies the aforementioned structural characteristics as a pigment dispersant, thereby achieving a high pigment content and good storage stability.

[0018] In this embodiment, the mass of the polymer is 10%-30% of the mass of the pigment. Although the polymer accounts for a relatively low mass percentage compared to the pigment, it still makes the pigment dispersion relatively stable, and the pigment accounts for a relatively high mass percentage. This, to some extent, reflects the strong dispersing ability of the polymer provided in this application for pigments.

[0019] In some embodiments of this application, the pigment dispersant further includes other dispersants. The dispersibility of the pigment dispersion can be further improved by combining the above-described polymer with other dispersants having a structure different from that polymer.

[0020] In this embodiment of the application, the pigment content in the pigment dispersion is in the range of 10%-85% by mass. Because the above-mentioned polymer is used as the pigment dispersant, the pigment content in the dispersion can be controlled within a wide range, and can be adjusted to a higher level as needed, while maintaining good storage stability.

[0021] In this application embodiment, the solvent includes one or more of ester solvents, ether solvents, and ketone solvents. The polymers described in this application embodiment have high solubility in these organic solvents.

[0022] In this embodiment, the initial viscosity of the pigment dispersion at room temperature is below 10 mPa·s. This low initial viscosity at room temperature indicates good fluidity and can reflect, to some extent, that the pigment is well dispersed and has not aggregated or thickened.

[0023] In this embodiment, the absolute value of the viscosity change rate of the pigment dispersion after standing at room temperature for one week is less than 5%. The viscosity of the pigment dispersion does not change significantly after prolonged storage, reflecting its high stability and suitability for long-term storage / application.

[0024] A fourth aspect of this application provides a patterned composition comprising the pigment dispersion described in the third aspect of this application, a photosensitive resin, a photopolymerizable monomer, and a photoinitiator.

[0025] Because the patterned composition uses the aforementioned well-dispersible pigment dispersion, it can achieve a high pigment content and good storage stability, thereby producing a patterned color resist material with good light transmittance for a specific wavelength band. When n is not 0 in the aforementioned polymer, the alkali solubility of the patterned composition can be further improved, resulting in a color resist pattern with high matching degree to the desired pattern.

[0026] In some embodiments of this application, the patterning composition further includes additives, which include one or more of leveling agents, defoamers, adhesion promoters, and antioxidants. Additives may be added as needed.

[0027] A fifth aspect of this application provides a patterned color resist film, which is formed by a patterning process using the patterning composition described in the fourth aspect of this application. Because the polymer described in this application is used as a pigment dispersant in the patterning composition, the patterned color resist film formed by this patterning composition has high transmittance for the desired specific wavelength of light and good pattern morphology.

[0028] A sixth aspect of this application provides a color filter, which includes a substrate and a color resist layer disposed on the substrate. The color resist layer includes at least one patterned color resist film as described in the fifth aspect of this application. Because the color resist layer of this color filter includes the patterned color resist film described above, the color filter has a better filtering effect.

[0029] This application also provides a method for preparing a polymer, comprising the following steps:

[0030] (1) In the presence of a chain transfer agent and an initiator with the general structural formula R1-C(=S)-S-R2, the first monomer shown in formula (i1) and / or the second monomer shown in formula (i2) are polymerized in an organic solvent to obtain an intermediate mother liquor.

[0031] (2) Add the mixture containing the third monomer and initiator shown in formula (i3) to the intermediate mother liquor and continue the polymerization reaction to obtain the polymer;

[0032]

[0033] In this polymer, each R is independently selected from hydrogen atoms or methyl groups; R1 is independently selected from 1-4 ethoxy repeating units terminal to methyl or ethyl groups; R2 is independently selected from halogenated or unsubstituted branched alkyl groups; R3 independently includes alkyl groups substituted with cyclic amino groups, chain amino groups, or their quaternary ammonium groups; in the polymer, the degree of polymerization n of the first repeating unit derived from the first monomer and the degree of polymerization p of the second repeating unit derived from the second monomer are independently in the range of 0-60, and n+p is in the range of 40-60; the degree of polymerization m of the third repeating unit derived from the third monomer is in the range of 5-25.

[0034] The polymer is prepared by RAFT reaction. It has a narrow molecular weight distribution and an ordered and controllable structure. The polymer of each repeating unit is relatively easy to control within the above range, so as to ensure that the polymer has excellent pigment dispersion ability and good alkali solubility when n is not 0. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of a color filter structure.

[0036] Figure 2 It shows Figure 1 A schematic diagram of one arrangement of the color resists in the intermediate color resist layer.

[0037] Figure 3 A schematic diagram of a patterning process provided in an embodiment of this application is shown.

[0038] Figure 4 The image shows the hydrogen nuclear magnetic resonance spectrum of polymer P1 obtained in Example 1.

[0039] Figure 5 The image shows the hydrogen nuclear magnetic resonance spectrum of polymer P2 obtained in Example 2.

[0040] Figure 6 The image shows the hydrogen nuclear magnetic resonance spectrum of polymer P2 obtained in Example 3.

[0041] Figure 7The images show photographs of the film formed using the pigment dispersion of Example 1 before and after immersion in alkaline developing solution; wherein, (a) is the inset before immersion and (b) is the inset after immersion. Detailed Implementation

[0042] The embodiments of this application will now be described in conjunction with the accompanying drawings.

[0043] Figure 1 This is a schematic diagram of a color filter (CF). Figure 2 It shows Figure 1 A schematic diagram of one arrangement of the color resists in the intermediate color resist layer. For example... Figure 1 and Figure 2 As shown, the color filter 100 includes a substrate 10 and a color resist layer 20 (or color filter film) disposed on one side of the substrate 10. Incident light is mixed after passing through the color resist layer 20 to display the desired color. The color resist layer 20 includes multiple color resists arranged in an array, specifically including a first color resist 201 (e.g., a red color resist), a second color resist 202 (e.g., a green color resist), and a third color resist 203 (e.g., a blue color resist). Any adjacent color resists have different colors. The multiple arrays of first color resists 201 constitute a first patterned color resist film, the multiple arrays of second color resists 202 constitute a second patterned color resist film, and the multiple arrays of third color resists 203 constitute a third patterned color resist film.

[0044] In some embodiments, the color filter 100 further includes a black matrix 30 disposed on the substrate 10. Any two adjacent color filters are separated by the black matrix 30. In some cases, the color filter layer 20 may be located at the cutouts of the black matrix 30. The black matrix 30 generally includes multiple intersecting light-blocking strips. The black matrix 30 can isolate adjacent color filters to prevent color mixing between them and also has a light-blocking function.

[0045] The patterned color resist films of each color are generally formed by a patterning process using patterned compositions of corresponding colors. The patterning process generally includes steps such as coating the patterned composition, exposure, and development. Each patterned composition generally includes a pigment dispersion containing the corresponding pigment, a photosensitive resin, a photopolymerizable monomer, and a photoinitiator. When the film layer formed by the patterned composition is irradiated / exposed through a mask with a predetermined pattern, the photosensitive resin and photopolymerizable monomer in the exposed areas undergo photocrosslinking reactions, while the unexposed areas do not react, resulting in a difference in the solubility of the developer between the exposed and unexposed areas. Subsequently, the developer selectively dissolves the exposed or unexposed areas, forming a patterned color resist film with a specific pattern on the substrate 10. Generally, the developer used is an alkaline aqueous solution. The unexposed areas of the patterned composition film layer are washed away by the alkaline developer, thus the pattern of the color resist film formed on the substrate is complementary to the pattern of the exposure mask.

[0046] Each pigment dispersion generally includes a pigment and a pigment dispersant. The dispersion of the pigment by the pigment dispersant significantly affects the pigment content and storage stability of the patterned composition used to form color resist patterns. For example, the better the pigment dispersion in the pigment dispersion, the higher the pigment content in the patterned composition can be, and the better the transmittance of its film to specific wavelengths of light. The stronger the dispersing ability of the pigment dispersant, the better the storage stability of the pigment dispersion and the patterned composition, allowing for long-term preservation and a longer application window for the patterned composition. However, currently commonly used pigment dispersants have poor pigment dispersion effects, making it difficult to achieve high pigment content and good storage stability in pigment dispersions / patterned compositions using them. To solve this problem, embodiments of this application provide a novel pigment dispersant with excellent pigment dispersion ability, its preparation method, and its application.

[0047] Specifically, this application provides a polymer that can be used as a pigment dispersant, the polymer having the structure shown in formula (Ⅰ):

[0048]

[0049] Wherein, co represents copolymerization, b represents block, R4-C(=S)-S- and -R5 constitute the chain transfer agent used in the RAFT (Reversible Addition-Fragmentation Chain Transfer Polymerization) reaction; each R is independently selected from hydrogen atoms (H) or methyl groups (-CH3), and R1 is independently selected from those with C-terminal groups. 1-4The alkyl group has 1-4 repeating ethoxy units; R2 is independently selected from halogenated or unsubstituted branched alkyl groups; R3 independently includes alkyl groups substituted with cyclic amino groups, chain amino groups or their quaternary amino groups; 0≤n≤60, 0≤p≤60, and n+p is in the range of 40-60, m is in the range of 5-25.

[0050] If we denote the repeating unit corresponding to the above label n (the structure is shown in the following equation (1)) as the first repeating unit, the repeating unit corresponding to the label p (the structure is shown in the following equation (2)) as the second repeating unit, and the repeating unit corresponding to the label m (the structure is shown in the following equation (3)) as the third repeating unit:

[0051]

[0052] In this case, n represents the degree of aggregation of the first repeating unit, p represents the degree of aggregation of the second repeating unit, and m represents the degree of aggregation of the third repeating unit.

[0053] It is understood that the polymer described above is a block copolymer, comprising two blocks, such as a first block and a second block. The first block of the polymer comprises a first repeating unit as shown in formula (1) and / or a second repeating unit as shown in formula (2), and the second block of the polymer comprises a third repeating unit as shown in formula (3). One end of the first block is connected to one end of the second block, the other end of the second block is capped by R4-C(=S)-S-, and the other end of the first block is capped by R5. It is understood that the first block may comprise only at least one first repeating unit as shown in formula (1) (in which case p=0), or only at least one second repeating unit as shown in formula (2) (in which case n=0), or may comprise both at least one first repeating unit as shown in formula (1) and at least one second repeating unit as shown in formula (2) (in which case n>0, p>0). It should be noted that when n>0 and p>0, in formula (I), the first repeating unit may be connected to R5, or the second repeating unit may be connected to R5.

[0054] The first repeating unit shown in formula (1) can be referred to as a repeating unit derived from short-chain polyethers of (meth)acrylate. The second repeating unit shown in formula (2) can be referred to as a repeating unit derived from branched alkyl esters of (meth)acrylate. The third repeating unit shown in formula (3) can be referred to as a repeating unit derived from aminoalkyl esters of (meth)acrylate.

[0055] The third repeating unit can anchor the pigment via the nitrogen atom in the amine group or its quaternary ammonium group, improving the dispersibility and dispersion stability of the polymer. Compared to straight-chain alkyl esters of acrylic acid, the second repeating unit derived from branched-chain alkyl esters of acrylic acid can increase the steric hindrance of the polymer, facilitating the formation of micelles on the pigment surface and further enhancing the dispersion effect of the polymer on the pigment, achieving the goal of dispersing a large amount of pigment with a small amount of dispersant. The first repeating unit with short-chain polyether side chains can improve the alkali solubility of the polymer, making it easier for the patterned composition containing it to be washed away by alkaline developer during the patterning process, thus improving the quality of the obtained pattern, and less likely to form unstable physical encapsulation of pigment particles, affecting dispersion stability.

[0056] Furthermore, by controlling the degree of polymerization m of the third repeating unit of the above polymer to be in the range of 5-25, and the sum of the degree of polymerization n of the first repeating unit and the degree of polymerization p of the second repeating unit to be in the range of 40-60, it can be ensured that the above polymer has excellent dispersibility for pigments. Pigment dispersions using it as a dispersant can meet the requirements of high pigment content and good storage stability. When the degree of polymerization n of the first repeating unit is not 0, the pigment dispersion can also take into account high alkali solubility.

[0057] Furthermore, the structural fragments of the chain transfer agent used in the RAFT reaction end-capped the first and second segments of the polymer, indicating that the polymer was prepared based on the RAFT reaction. This resulted in the polymer being a block copolymer with an ordered structure, controllable degree of polymerization of each repeating unit, and a narrow molecular weight distribution. This is beneficial for pigment dispersions using this polymer as a pigment dispersant to have lower viscosity and better dispersion performance.

[0058] R1 can be represented as -(CH2CH2O). i -R', where i is an integer from 1 to 4, and R' is a C 1-4 Alkyl group. If i in R1 is 6 or more, the repeating unit shown in formula (1) is a high molecular weight acrylic polyether structure, which has a long-chain polyether structure. It is very easy to form an unstable physical coating on pigment particles, and it is easy to detach from the surface of pigment particles and cause pigment aggregation, affecting the dispersion stability of pigment. Specifically, i can be 1, 2, 3, or 4. R' is methyl, ethyl, n-propyl, isopropyl, or n-butyl, etc. In some embodiments, R' is methyl or ethyl. This is more conducive to reducing the influence of the above-mentioned first repeating unit on the dispersion stability of pigment.

[0059] In R2 above, the halogenated or unsubstituted branched alkyl group has 3 or more carbon atoms. In some embodiments, the branched alkyl group has 3-20 carbon atoms, specifically 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 15, 18, etc. An appropriate number of branched alkyl groups can ensure that the side chain steric hindrance of the second repeating unit is large, thereby enhancing the dispersion effect on the pigment. In some possible embodiments, the branched alkyl group has 5-12 carbon atoms, more specifically 5-10. Furthermore, halogenated branched alkyl groups refer to branched alkyl groups substituted with halogen atoms. The halogen atom includes one or more of fluorine (Cl), bromine (Br), and iodine (I). The halogenation can be partial or complete. Complete halogenation means that all hydrogen atoms in the branched alkyl group are substituted with halogen atoms.

[0060] For example, the branched alkyl group can be halogenated or unsubstituted isopropyl, isobutyl, tert-butyl, isopentyl (e.g., with the chemical formula -CH2CH2-CH(CH3)2, -CH2CH(CH3)CH2-CH3, -CH(CH3)CH2CH2CH3, or -CH(CH3)CH(CH3)2, etc.), tert-pentyl (e.g., with the chemical formula -C(CH3)2-CH2CH3), isohexyl (e.g., with the chemical formula -CH2CH2CH2-CH(CH3)2, -CH2CH2CH(CH3)CH2-CH3, -CH2CH(CH3)CH2CH2CH3, or -CH2CH(CH3)CH(CH3)2, etc.), tert-hexyl (e.g., with the chemical formula -C(CH3)2-CH(CH3)2, or... Examples of such compounds include -C(CH3)2-CH2CH2CH3, isoheptyl (e.g., chemical formula -(CH2)4-CH(CH3)2 or -CH2-CH(CH3)-(CH2)3-CH3), tert-heptyl (e.g., chemical formula -C(CH3)2-(CH2)3CH3), isooctyl (e.g., structural formula -CH2-CH(CH2CH3)-(CH2)3-CH3 or -(CH2)5-CH(CH3)2), tert-octyl (e.g., chemical formula -C(CH3)2-(CH2)4CH3 or -C(CH3)2-CH2-C(CH3)3), isononyl (e.g., chemical formula -(CH2)6-CH(CH3)2), or tert-nonyl (e.g., chemical formula -C(CH3)2-(CH2)5CH3), etc.

[0061] In this application, R3 includes an alkyl group substituted with a cyclic amino group, a chain amino group, or a quaternary ammonium group thereof. Specifically, the cyclic amino group refers to an amino group containing a tertiary nitrogen atom on the ring, such as an aliphatic cyclic amino group or an aromatic heterocyclic amino group. Exemplarily, the cyclic amino group can be piperidinyl, morpholinyl, pyridinyl, pyrroleyl, etc. The chain amino group can include a monoalkyl amino group (-NHR). 1 ), dialkylamino (-N(R) 1 (R) 2 One or more of the following: diarylamine (e.g., diphenylamine), arylalkylamine (e.g., -N(Ph)(CH3), where Ph represents phenyl).

[0062] In some embodiments of this application, R3 is selected from C groups substituted with dialkylamine groups or their quaternary ammonium groups. 2-4 Alkyl group, wherein each alkyl group in the dialkylamino group is independently selected from substituted or unsubstituted C4 groups. 1-6 Alkyl groups. The substituents in the substituted alkyl groups may include halogen atoms, alkoxy groups, or amino groups, etc. In this case, the monomer corresponding to formula (3) above exhibits higher polymerization reactivity with other monomers, and the amino group or its quaternary ammonium group in R3 has a more stable anchoring effect on the pigment through its nitrogen atom, thus resulting in better pigment dispersion of the polymer. For example, the dialkylamino group may be dimethylamino (-N(CH3)2), diethylamino (-N(CH2CH3)2), dipropylamino (-N(CH2CH2CH3)2), dibutylamino (-N(CH2CH2CH2CH3)2), diethylamino (-N(CH3)(CH2CH3)), etc.

[0063] With the general chemical formula -N(R) 1 (R) 2 Taking the dialkylamine group of ) as an example, its quaternary amide group can be represented as Among them, X - It is an anion, R 3 It is a monovalent substituted or unsubstituted hydrocarbon group, for example, it can be a substituted or unsubstituted alkyl group.

[0064] In this application, the structure of the chain transfer agent R4-C(=S)-S-R5 for the RAFT reaction, consisting of R4-C(=S)-S-R5 and R5, is not particularly limited, as long as it is suitable for the polymerization of (meth)acrylates. R4 and R5 may vary depending on the type of chain transfer agent.

[0065] In some embodiments of this application, R4 is independently selected from phenyl (Ph-), dodecyl (C-), and phenyl (C-). 12 H 25 -) or dodecyl groups linked with sulfide bonds (C 12 H 25-S-); R5 is independently selected from one of -CN, -CH2CN, -C(CH3)2-CN, -CH2-COOH, -CH2-CH2-COOH, -CH(CH3)-COOH, -C(CH3)2-COOH, -C(CH3)(CN)-CH2CH2COOH, and -C(CH3)2-Ph. Wherein, Ph represents phenyl. The RAFT chain transfer agent R4-C(=S)-S-R5, selected from these R4 and R5, provides high controllability for the polymerization of (meth)acrylate monomers, which is beneficial for obtaining polymers with narrow molecular weight distribution and controllable structure.

[0066] For example, chain transfer agents with the general structural formula R4-C(=S)-S-R5 may include any of the following substances:

[0067]

[0068]

[0069] It is understood that in this application, n and p are integers between 0 and 60, and n+p is an integer between 40 and 60. m is an integer between 5 and 25. Specifically, n+p can be 41, 42, 43, 44, 45, 46, 47, 48, 49, 50, 51, 52, 53, 54, 55, 56, 57, 58, or 59.

[0070] In some embodiments of this application, n > 0 and p > 0. Pigment dispersions using the above-mentioned polymer as a pigment dispersant can balance high pigment content, good storage stability, and high alkali solubility.

[0071] In some embodiments of this application, n is an integer between 10 and 35, and p is an integer between 8 and 25. In this case, with the combined action of the first repeating unit with a degree of polymerization of 10-35, the second repeating unit with a degree of polymerization of 8-25, and the third repeating unit with a degree of polymerization between 5 and 25, the polymer can better balance strong pigment dispersibility and good alkali solubility. Therefore, the pigment dispersion using the polymer as a pigment dispersant can achieve a high pigment content, excellent storage stability, and good alkali solubility. Exemplarily, n can specifically be 12, 15, 16, 18, 20, 21, 22, 23, 24, 25, 26, 27, 28, 29, 30, 31, 32, 33, etc. p can specifically be 9, 10, 11, 12, 15, 16, 18, 20, 21, 22, 23, 24, 25. In some embodiments, n is an integer between 18 and 31. p is an integer between 10 and 21.

[0072] In some possible implementations, n > 0, p > 0, and n + p is in the range of 40-55. In this case, the polymers described above, which are end-capped by the chain transfer agent used in the RAFT reaction, can better balance strong pigment dispersibility, good alkali solubility, and good solubility in common organic solvents.

[0073] In some embodiments of this application, the degree of polymerization m of the third repeating unit is an integer between 8 and 20, specifically 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, or 19. In some embodiments, m is in the range of 8-16, and further in the range of 10-16. In this case, the polymer exhibits a reasonably strong anchoring effect on the pigment while also possessing good solubility in organic solvents such as esters, ethers, and ketones.

[0074] It should be noted that the polymer described above may include a first repeating unit as shown in formula (1), or it may include multiple first repeating units with different structures as shown in formula (1). The degree of polymerization n of the aforementioned first repeating unit refers to the sum of the degrees of polymerization of all first repeating units conforming to formula (1). Similarly, the polymer described above may include a second repeating unit as shown in formula (2), or it may include multiple second repeating units with different structures. The polymer described above may include a first repeating unit as shown in formula (3), or it may include multiple third repeating units with different structures as shown in formula (1).

[0075] In this embodiment, the polymer's molecular weight distribution index (PDI) is less than 1.14. PDI is equal to the polymer's weight-average molecular weight M. w Number-average molecular weight M n The ratio is as follows. Since the above polymer is prepared based on the RAFT reaction, the polymer has a narrow molecular weight distribution, which is beneficial for pigment dispersions using this polymer as a pigment dispersant to have lower viscosity and better dispersion performance.

[0076] This application also provides a method for preparing the above-mentioned polymer. Specifically, the method for preparing the polymer includes the following steps:

[0077] (1) In the presence of a chain transfer agent and an initiator with the general structural formula R4-C(=S)-S-R5, the first monomer shown in formula (i1) and / or the second monomer shown in formula (i2) are polymerized in an organic solvent to obtain an intermediate mother liquor.

[0078]

[0079] In this embodiment, each R is independently selected from a hydrogen atom or a methyl atom, R11 is independently selected from 1-4 ethoxy repeating units with a terminal methyl or ethyl group, R2 is independently selected from halogenated or unsubstituted branched alkyl groups, and the degree of polymerization n of the first repeating unit derived from the first monomer and the degree of polymerization p of the second repeating unit derived from the second monomer are independently in the range of 0-60, and n+p is in the range of 40-60.

[0080] (2) Add the mixture containing the third monomer and initiator shown in formula (i3) to the intermediate mother liquor and continue the polymerization reaction to obtain the polymer;

[0081]

[0082] Wherein, R is independently selected from hydrogen atom or methyl, and R3 independently includes an alkyl group substituted with a cyclic amino group, a chain amino group or a quaternary amino group thereof; the degree of polymerization m of the third repeating unit derived from the third monomer is in the range of 5-25.

[0083] The polymer preparation method provided in this application is based on RAFT (Reversible Addition-Fragmentation Chain Transfer Polymerization). Step (1) first prepares a first block comprising a first repeating unit derived from a first monomer and / or a second repeating unit derived from a second monomer. Step (2) then prepares a second block comprising a third repeating unit derived from a third monomer. One end of the first block is capped with R5, and one end of the second block is capped with R4-C(=S)-S-. The polymer obtained by this RAFT reaction has an ordered and controllable structure, a narrow molecular weight distribution, and a PDI less than 1.14. It is understandable that in the intermediate mother liquor of step (1), the two ends of the first block are capped by the chain transfer agent fragments R4-C(=S)-S- and -R5, respectively. However, under the action of the initiator in step (2), the intermediate is activated, and the capping group R4-C(=S)-S- of its first block is broken, thus initiating the chain growth reaction of the third monomer free radical.

[0084] Furthermore, by adjusting the feeding ratio of the first monomer, the second monomer, and the third monomer, as well as the reaction time of each step, the degree of polymerization n of the first repeating unit, the degree of polymerization p, n+p of the second repeating unit, and the degree of polymerization m of the third repeating unit can be controlled within the above range, thereby achieving that the polymer has excellent dispersibility for pigments, and when the degree of polymerization n of the first repeating unit is not 0, the polymer can also maintain high alkali solubility.

[0085] The polymer prepared by the above method can have the structure shown in formula (Ⅰ). For the specific meaning of each reference numeral and the specific structural characteristics of the polymer, please refer to the description above in this application.

[0086] In step (1), the chain transfer agent can be a common chain initiator used in RAFT polymerization of acrylates. Exemplary chain transfer agents R4, R5, or those with the general structural formula R4-C(=S)-S-R5 can be found in the preceding description of this application.

[0087] In this application embodiment, in step (1), the initiator may include one or more of azo compounds and organic peroxides. These initiators can decompose to generate free radicals, which, under the guidance of the initiator free radicals, can generate monomer free radicals and undergo chain transfer and growth. Exemplarily, the azo compound may include one or more of azobisisobutyronitrile (AIBN), dimethyl azobisisobutyrate, azobisisoheptanenitrile, 1,1'-azo (cyanocyclohexane), etc., but are not limited thereto. The organic peroxide may include one or more of benzoyl peroxide (BPO), potassium persulfate, etc., but are not limited thereto. In some embodiments of this application, the initiator is an azo compound. The polymerization temperature is generally 50-100°C, for example, specifically 60°C, 70°C, 80°C, or 90°C. The polymerization time in step (1) can be controlled according to the degree of polymerization of the repeating units corresponding to the first monomer and the second monomer.

[0088] In this embodiment of the application, in step (1), the organic solvent may include one or more of 1,4-dioxane, N-methylpyrrolidone (NMP), benzene, etc., but is not limited thereto. It is acceptable as long as the aforementioned monomers, chain transfer agents, and initiators can dissolve in the organic solvent. Accordingly, in step (2), the solvent in the mixture containing the third monomer and initiator shown in formula (i3) can also be independently selected from the aforementioned organic solvents.

[0089] In step (2), the temperature of the polymerization reaction can be the same as or different from that in step (1). The time of the polymerization reaction in step (2) can be controlled according to the degree of polymerization of the repeating unit corresponding to the third monomer.

[0090] In this application, the polymerization reactions in steps (1) and (2) can be carried out in the presence of an inert atmosphere. The inert atmosphere can be a nitrogen atmosphere, an argon atmosphere, or a mixture of nitrogen and argon.

[0091] In some embodiments of this application, after step (2), step (3) is further included: the reaction solution obtained in step (2) is poured into petroleum ether under stirring, and allowed to settle under an ice-water bath. The initial precipitate is dissolved in tetrahydrofuran (THF), and then petroleum ether is added under stirring and allowed to settle again under an ice-water bath. The desired polymer product is then precipitated and dried.

[0092] This application also provides the application of the polymer described above in the preparation of pigment dispersants, pigment dispersions, pigment-containing photosensitive compositions, or color resists.

[0093] The polymer described above can be used as a pigment dispersant to disperse organic pigments. Furthermore, the polymer can also be used to formulate pigment dispersions, which can be used to formulate pigment-containing photosensitive compositions, which can be used to prepare color resist patterns.

[0094] Specifically, this application provides a pigment dispersion comprising a pigment, a pigment dispersant, and a solvent, wherein the pigment dispersant comprises the polymer described in this application.

[0095] The polymer provided in this application satisfies the aforementioned structural characteristics and exhibits excellent pigment dispersibility. Therefore, the pigment dispersion using this polymer as a pigment dispersant can achieve high pigment content and good storage stability. Furthermore, when the degree of polymerization n of the first repeating unit of the polymer is not 0, the pigment dispersion also exhibits high alkali solubility. Thus, the patterning composition using this pigment dispersion can better meet the requirements of subsequent patterning processes, and unexposed areas can be effectively washed away by alkaline developer to obtain a high-quality pattern.

[0096] In this embodiment, the pigment may include one or more of the following: red, green, blue, yellow, orange, and purple pigments. The specific pigment color can be selected based on the color of the color resist film to be prepared. The pigment can be organic or inorganic, with organic pigments being more common.

[0097] The solvent in the aforementioned pigment dispersion is generally an organic solvent. In the embodiments of this application, the solvent may include one or more of ester solvents, ether solvents, and ketone solvents. For example, ester solvents may include one or more of propylene glycol methyl ether acetate (PGMEA), propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethyl acetate, butyl acetate, and γ-butyrolactone (GBL). Ether solvents may include, but are not limited to, one or more of propylene glycol methyl ether (PGME), propylene glycol monoethyl ether, ethylene glycol monomethyl ether, and ethylene glycol monoethyl ether. Ketone solvents may include, but are not limited to, one or more of acetone, methyl ethyl ketone, and cyclohexanone.

[0098] In this embodiment of the application, the polymer in the pigment dispersion comprises 10%-30% of the pigment mass. Although the polymer has a relatively low mass percentage compared to the pigment, it still contributes to the stability of the pigment dispersion, resulting in a relatively high pigment mass percentage. This demonstrates the polymer's strong ability to disperse pigments. For example, the polymer mass can be 12%, 15%, 17%, 19%, 20%, 22%, 25%, 28%, or 29% of the pigment mass, etc.

[0099] In some embodiments of this application, the pigment dispersant further includes other dispersants. It is understood that the structures of these other dispersants differ from the polymers described in the embodiments of this application. In some embodiments, the other dispersant may be a dispersing resin containing carboxyl groups. It may act as an auxiliary dispersant (its dispersing effect is significantly weaker than that of the polymers described in this application), but its primary function is alkali solubility.

[0100] In this embodiment of the application, the pigment content in the pigment dispersion is in the range of 10%-85% by mass. Because the aforementioned polymer is used as the pigment dispersant, the pigment content in the dispersion can be controlled to a high level, while also exhibiting high storage stability. Specifically, the pigment content by mass can be 15%, 18%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70%, 72%, 75%, 78%, 80%, or 82%, etc.

[0101] In this embodiment, the D50 particle size of the pigment dispersion is less than 100 nm. This D50 particle size can be measured by a laser particle size analyzer. A smaller D50 particle size indicates that the substances in the pigment dispersion (especially the pigment) are well dispersed, and there are no large agglomerates.

[0102] In this embodiment, the absolute value of the viscosity change rate of the pigment dispersion after standing at room temperature for one week is less than 5%. If the initial viscosity of the pigment dispersion at room temperature is denoted as η0, and the viscosity after standing at room temperature for one week is denoted as η1, then the absolute value of the viscosity change rate is denoted as k, where k = |η1 - η0| / η0, and k ≤ 5%. The small viscosity change rate indicates that the pigment dispersion provided in this embodiment has high stability; it can be left to stand for a long time without agglomeration or drastic viscosity changes. Therefore, the patterning composition using this pigment dispersion also has high stability, can have a long processing time window, and can maintain low viscosity and good flowability until the patterned composition is completely coated.

[0103] Specifically, the aforementioned k can be below 4%, 3%, 2.5%, 2.3%, 2.2%, 2%, or even below 1%. It should be noted that when characterizing the viscosity change rate of the above pigment dispersion, "room temperature" can refer to any temperature between 20℃ and 40℃, such as 22℃, 25℃, 28℃, 30℃, 32℃, or 35℃, with 25℃ being the most common. The room temperature values ​​corresponding to the above pigment dispersion before and after standing for one week are allowed to fluctuate to some extent; comparisons are not required to be made at completely equal temperatures.

[0104] In a possible embodiment of this application, the initial viscosity η0 of the pigment dispersion at room temperature can be below 10.0 mPa·s, that is, below 10.0 cps. A low initial viscosity η0 at room temperature indicates good fluidity and can reflect, to some extent, that the pigment dispersion in the dispersion is good, without aggregation or thickening. In some embodiments, the initial viscosity η0 of the pigment dispersion at room temperature is 2.0-8.0 mPa·s. Exemplarily, η0 can specifically be 2.2 mPa·s, 2.5 mPa·s, 2.8 mPa·s, 3.0 mPa·s, 3.2 mPa·s, 3.5 mPa·s, 4.0 mPa·s, 4.5 mPa·s, 5.0 mPa·s, 5.5 mPa·s, 6.0 mPa·s, 6.5 mPa·s, 7.0 mPa·s, 7.5 mPa·s, or 7.8 mPa·s, etc. In some implementations, η0 is 3.5-7.5 mPa·s.

[0105] This application also provides a patterned composition comprising the pigment dispersion described in this application, as well as a photosensitive resin, a photopolymerizable monomer, and a photoinitiator.

[0106] Because the polymer described in the embodiments of this application is used as a pigment dispersant in the patterned composition, it has excellent pigment dispersion ability. Therefore, the pigment is uniformly dispersed in the patterned composition, and a high pigment content and good storage stability can be achieved. When the degree of polymerization n of the first repeating unit of the polymer is not 0, the alkali solubility of the patterned composition can be further improved, and its film layer can obtain a pattern with high matching degree to the desired pattern after exposure and development with an alkaline developer.

[0107] Under exposure from an appropriate wavelength (such as ultraviolet light) and initiated by a photoinitiator, the photosensitive resin and photopolymerizable monomers in the patterned composition can undergo a polymerization and cross-linking reaction, and intertwine with pigments to obtain a cured product with a certain network structure.

[0108] Optionally, the photosensitive resin may include an epoxy acrylate resin with a carboxyl group, or an acrylate resin with both carboxyl and olefin groups. That is, the former is an acrylate resin that simultaneously has repeating units with carboxyl groups on the side chain and repeating units with epoxy groups on the side chain. The latter is an acrylate resin that simultaneously has repeating units with carboxyl groups on the side chain and repeating units with olefin groups at the end of the side chain. The photopolymerizable monomer may be a compound having one or more carbon-carbon double bonds in its molecular structure, such as an acrylate monomer. The photoinitiator, upon irradiation with light of a certain wavelength, can generate free radicals, and through the transfer of these free radicals, can initiate the polymerization reaction of the photopolymerizable monomer, photosensitive resin, etc. Exemplarily, the photoinitiator may include one or more of acetophenones, α-aminoalkylphenyl ketones, benzophenones, benzoin, thioxanthones, anthraquinones, triazines, and oximes, but is not limited thereto.

[0109] In some embodiments of this application, the patterned composition further includes additives, including one or more of leveling agents, defoamers, adhesion promoters, and antioxidants. These additives can be added as needed. Leveling agents can reduce the surface tension of the patterned composition, promoting the formation of a smooth and uniform coating film. Defoamers can effectively reduce the probability of bubble formation during the preparation and use of the patterned composition, improving the quality and reliability of its coating film. Adhesion promoters can improve the adhesion of the patterned composition film to the substrate surface.

[0110] This application also provides a patterned color resist film, which can be formed by the patterning composition described in this application through a patterning process. This patterning process generally includes steps such as coating, exposure, and development of the patterned composition.

[0111] Because the polymer described in the present application embodiment is used as the pigment dispersant in the above patterned composition, the patterned color resist film formed by the patterned composition has high transmittance for the required specific wavelength of light and good pattern morphology.

[0112] Specifically, such as Figure 3 As shown, the patterning process of this color resist film includes:

[0113] S01, the patterned composition described in the embodiments of this application is coated on a substrate to form a patterned material film layer on the substrate;

[0114] S02, the patterned material film is exposed using a photomask;

[0115] S03, using a developer to develop the exposed patterned material film layer to form a patterned color resist film on the substrate.

[0116] In step S01, the substrate to which the patterned composition is to be coated is generally a transparent optical substrate, such as glass, polycarbonate, polyimide (PI), polyethylene terephthalate (PET), or the aforementioned substrate material with other film layers disposed on its surface. Exemplary other film layers may include a dielectric layer (such as SiO2 or Si3N4), a black matrix, etc.

[0117] The coating methods for the above-mentioned patterned composition include, but are not limited to, spin coating, dip coating, brush coating, spray coating, and roller coating. In some possible embodiments, the coating is specifically spin coating. Depending on the size of the substrate, an appropriate volume of the above-mentioned patterned composition can be taken and spin-coated onto the substrate to form a patterned material film layer of a certain thickness.

[0118] In some embodiments of this application, after coating the patterned composition described above, a pre-baking process is performed to minimize the solvent content in the patterned composition. Typical pre-baking temperatures can be 60-150°C, and the process time can be between 10 seconds and 30 minutes.

[0119] In step S02, the exposure source used for exposure can be ultraviolet light with a wavelength below 400 nm. Specifically, the exposure process includes: placing a mask with a predetermined pattern above the aforementioned patterned material film layer, allowing the exposure source to irradiate the patterned material film layer through the mask to achieve selective exposure (i.e., patterned exposure). The mask can be selected / customized according to the desired pattern. During the exposure process, the aforementioned patterned material film layer undergoes a cross-linking and curing reaction, while the unexposed areas do not react. The chemical properties of the exposed and unexposed areas change.

[0120] In some embodiments of this application, the patterned material film can be selectively baked after exposure and before development. This baking operation can promote the further completion of any incomplete cross-linking reactions in the film. Typical baking temperatures can be 60-150°C.

[0121] Because the chemical properties of the exposed part of the patterned material film layer change, its solubility in the developer differs from that in the unexposed area. Therefore, in step S03, the film material in the exposed or unexposed area can be selectively dissolved by the developer to form a patterned thin film on the substrate.

[0122] In some embodiments of this application, the developer used in step S03 is an alkaline aqueous solution. After treatment with this developer, the unexposed areas of the patterned material film can be washed away by the alkaline developer, resulting in negative development. This leaves a negative pattern on the substrate that is complementary to the pattern of the exposure mask, such as... Figure 3 As shown. It is understood that the patterned color resist film formed in this case includes the cured product of the above-described patterned composition.

[0123] Specifically, the alkaline substances in the alkaline aqueous solution may include one or more of tetramethylammonium hydroxide (TMAH), tetraethylammonium hydroxide (TEAH), tetrapropylammonium hydroxide (TPAH), tetrabutylammonium hydroxide (TBAH), triethanolamine, etc. A water rinsing process may be selectively added after development to make the film layer cleaner.

[0124] In some embodiments of this application, after development in step S03, the obtained patterned color resist film may be subjected to a post-baking process to improve the adhesion, hardness, etc. of the film. For example, the post-baking process may be performed at a temperature of 60°C-250°C.

[0125] This application also provides a color filter. As shown above, the color filter 100 includes a substrate 10 and a color resist layer 20 disposed on one side of the substrate 10. The color resist layer 20 includes at least one of the patterned color resist films described in this application embodiment.

[0126] Specifically, the color resist layer 20 includes multiple color resists arranged in an array, such as a first color resist 201 (e.g., a red color resist, also called an R color resist), a second color resist 202 (e.g., a green color resist, also called a G color resist), and a third color resist 203 (e.g., a blue color resist, also called a B color resist). The multiple arrays of the first color resist 201 constitute a first color resist film, the multiple arrays of the second color resist 202 constitute a second color resist film, and the multiple arrays of the third color resist 203 constitute a third color resist film. Alternatively, the color resist layer 20 can be described as being constructed from a first patterned color resist film, a second patterned color resist film, and a third patterned color resist film.

[0127] In this application, at least one of the first, second, and third color resist films can be a color resist film formed using the patterned composition described above. In some embodiments of this application, the first, second, and third color resist films can be prepared sequentially. For example, firstly, a first patterned composition is applied to a substrate 10 to form a first color resist film using a patterning process; then, a second patterned composition is applied to the substrate 10 with the first color resist film to form a second color resist film using a patterning process; finally, a third patterned composition is applied to the substrate 10 with the first and second color resist films to form a third color resist film using a patterning process. The color resist blocks of the second, third, and first color resist films do not overlap or intersect.

[0128] It should be noted that the color resist layer 20 is not limited to including the R color resist, G color resist, and B color resist mentioned above. In some cases, it may also include color resists of other colors.

[0129] In some embodiments of this application, the color filter 100 further includes a black matrix 30 disposed on the substrate 10. Any two adjacent color filters are separated by the black matrix 30. The black matrix 30 can be formed on the substrate 10 first, and then the color filter layer 20 can be formed in the cutouts of the black matrix. Furthermore, the color filter 100 may also include a protective layer (not shown) covering the color filter layer 20 and the black matrix 30.

[0130] The color filter provided in this application embodiment can be used in image sensors or display panels, etc. That is, image sensors or display panels may include color filters.

[0131] Specifically, the image sensor can be a CMOS image sensor, an optical sensor and a core component of a camera module. It utilizes the photoelectric conversion function of optoelectronic devices to convert light signals on the photosensitive surface into electrical signals proportional to the light signals, and then converts the electrical signals into digital signals for output. A CMOS image sensor mainly includes a circuit layer, photodiodes, color filters, and microlenses, and can be used in electronic devices with camera functions. The display panel generally includes a CF substrate, an array substrate, and a liquid crystal layer located between them. Display panels can be used in electronic devices with display functions.

[0132] This application also provides an electronic device, which includes the aforementioned image sensor or display panel. Exemplarily, the electronic device may include, but is not limited to, a mobile phone, tablet computer, laptop computer, camera, camcorder, television set, wearable electronic device, virtual reality device, in-vehicle device, etc.

[0133] The technical solution of this application will be further described below through specific embodiments.

[0134] Example 1

[0135] (I) Preparation of polymer P1:

[0136] (1) 7.567g of cyanoisopropyl dithiobenzoate (2-Cyanoprop-2-yl-dithiobenzoate, abbreviated as CPDB, chemical formula is...) 68.451g of 2-ethylhexylmethacrylate (EHMA, chemical formula: 199.479g of 2-methyl-2-acrylate-2-(2-methoxyethoxy)ethyl ester (DEGMA, chemical formula: [missing information]) 1.6842 g of azobisisobutyronitrile (AIBN) and 415.781 g of solvent 1,4-dioxane were added to a 500 mL five-necked flask equipped with a rotor. The stirring speed was maintained at 350 rpm, and nitrogen gas was bubbled through the flask for 30 min. The system was then heated to 50 °C and reacted under a nitrogen atmosphere for 46 h. After the reaction was completed, the first block mother liquor was obtained. Subsequently, the reaction system was rapidly cooled to below 30 °C while maintaining nitrogen gas purging.

[0137] (2) Weigh 64.497 g of 2-(Dimethylamino)ethylmethacrylate (DMAEMA, chemical formula: 1.6842 g of AIBN and 99.27 g of 1,4-dioxane were added to 250 mL two-necked flasks equipped with rotors, and the stirring speed was maintained at 350 rpm. Nitrogen gas was bubbled through the flasks for 10 min to obtain mixture 1.

[0138] (3) Next, the mixture 1 was injected into the first block mother liquor, and the stirring speed was maintained at 350 rpm. Nitrogen gas was bubbled through the mixture for 15 min. After bubbling, the reaction system was heated to 50°C and the reaction was continued for 46 h under a nitrogen atmosphere. After the reaction was completed, the second block mother liquor was obtained.

[0139] (4) The mother liquor of the second block was diluted 2 times with tetrahydrofuran (THF). Then, the diluted solution was added dropwise to 2L of petroleum ether while stirring at 500rpm. After the diluted solution was added, the resulting mixed solution was allowed to stand in an ice-water bath for 30min. The supernatant was then poured off. The precipitate was dissolved again with 50mL of THF and petroleum ether was added in batches (200mL / time * 10 times) while stirring. The mixture was then allowed to stand in an ice-water bath for 30min. The supernatant was then poured off and the resulting precipitate was dried in a vacuum oven at 50℃ for 24h to obtain the final product, namely polymer P1.

[0140] The structural formula of polymer P1 can be represented as:

[0141]

[0142] The final product P1 obtained above was subjected to nuclear magnetic resonance analysis. Figure 4 The proton nuclear magnetic resonance spectrum of polymer P1 obtained in Example 1 ( 1 HNMR spectrum. Figure 4 The peak at 3.399 ppm represents the characteristic peak of -CH2CH2O- from the monomer DEGMA, the peak at 2.280 ppm represents the characteristic peak of -N(CH3)2 from the monomer DMAEMA, and the peaks at 4.110 ppm and 3.840 ppm represent the characteristic peaks of -CH2- from the adjacent ester groups of the three monomers EHMA, DEGMA and DMAEMA.

[0143] In addition, the polymer P1 was subjected to gel permeation chromatography (GPC), which revealed that the weight-average molecular weight (Mw) of P1 was 10000 g / mol and the molecular weight distribution (PDI) was 1.09. The GPC results, combined with 1H Fourier transform nuclear magnetic resonance (NMR) spectroscopy, showed that the degree of polymerization (m) of the repeating units derived from the monomer DMAEMA was 12, the degree of polymerization (n) of the repeating units derived from DEGMA was 31, and the degree of polymerization (p) of the repeating units derived from the monomer EHMA was 20.

[0144] (II) Preparation of pigment dispersion:

[0145] 15.0 g of commercial red pigment R254, 2.55 g of the above polymer P1, 5.67 g of dispersion resin (which is a polymer with aryl or cycloalkyl and carboxyl groups), and 66.530 g of solvent PGMEA were added to a 250 mL glass bottle, along with 200 g of zirconia grinding beads with a diameter of 0.3 mm. The glass bottle was then shaken in a shaker for 1 hour. After shaking, the grinding beads and other solids were removed by filtration to obtain the pigment dispersion.

[0146] Stability test of pigment dispersion:

[0147] The viscosity of the pigment dispersion obtained in Example 1 was tested using a rotational viscometer, and the initial viscosity η0 was measured. The pigment dispersion was then allowed to stand at room temperature for one week, and its viscosity was tested again, obtaining the viscosity η1. The absolute value of the viscosity change rate k was calculated: k = |η1 - η0| / η0 × 100%. Wherein, if k is greater than 5%, the stability of the pigment dispersion is considered unsatisfactory; if k is less than 5%, the stability of the pigment dispersion is considered satisfactory.

[0148] Testing revealed that the pigment dispersion in Example 1 had an viscosity of η0 = 4.052 cps, an viscosity of η1 = 4.068 cps, and a viscosity of k = 0.4%. This indicates that the pigment dispersion in Example 1 showed little viscosity change after standing at room temperature for one week, demonstrating its good stability. This also illustrates the excellent dispersing ability of polymer P1 for organic pigments. Furthermore, using this polymer as a pigment dispersant can produce pigment dispersions with high pigment content and stability, as well as patterned compositions for manufacturing color resists.

[0149] Example 2

[0150] A polymer P2 differs from the preparation method of polymer P1 in Example 1 in that: in step (1), the amount of CPDB is 8.054g, the amount of EHMA is 51.001g, the amount of DEGMA is 212.303g, the amount of AIBN is 1.7925g, and the amount of 1,4-dioxane is 409.724g; in step (2), the amount of DMAEMA is 68.643g, the amount of AIBN is 1.7925g, and the amount of 1,4-dioxane is 105.650g.

[0151] Nuclear magnetic resonance analysis was performed on polymer P2 obtained in Example 2. Figure 5 The proton nuclear magnetic resonance spectrum of polymer P2 obtained in Example 2 ( 1 HNMR spectrum. From this Figure 5 The analysis of the obtained characteristic peaks is the same as described above. Figure 4 Similarly, this will not be repeated. Furthermore, GPC measurements showed that the weight-average molecular weight of polymer P2 was Mw = 10500 g / mol, and the molecular weight distribution (PDI) was 1.14. Combined with Fourier nuclear magnetic resonance (NMR) results, it was determined that the degree of polymerization of the repeating unit derived from monomer EHMA was p = 14, with m and n values ​​the same as in Example 1: m = 12 and n = 31.

[0152] According to the method described in Example 1, the polymer P2 provided in Example 2 was prepared into a pigment dispersion. The initial viscosity η0 of the pigment dispersion in Example 2 was measured to be 4.052 cps, and the viscosity η1 after standing at room temperature for one week was 4.068 cps. The calculated viscosity increase rate was 2.2%, which is less than 5%. This indicates that the polymer P2 has good dispersing ability for organic pigments, and the pigment dispersion in Example 2 has good stability.

[0153] Example 3

[0154] A polymer P3 differs from the preparation method of polymer P1 in Example 1 in that: in step (1), the amount of CPDB is 8.179g, the amount of EHMA is 40.695g, the amount of DEGMA is 215.606g, the amount of AIBN is 1.8203g, and the amount of 1,4-dioxane is 399.451g; in step (2), the amount of DMAEMA is 75.520g, the amount of AIBN is 1.8203g, and the amount of 1,4-dioxane is 116.01g.

[0155] Nuclear magnetic resonance analysis was performed on polymer P3 obtained in Example 3. Figure 6 The proton nuclear magnetic resonance spectrum of polymer P3 obtained in Example 3 (1H NMR spectrum) 1 HNMR spectrum. From this Figure 6 The analysis of the obtained characteristic peaks is the same as described above. Figure 4 Similarly, this will not be repeated. Furthermore, GPC measurements showed that polymer P3 had a weight-average molecular weight (Mw) of 10600 g / mol and a molecular weight distribution (PDI) of 1.09. Combined with Fourier nuclear magnetic resonance (NMR) results, the degree of polymerization (m) of the repeating units derived from monomer DMAEMA was 13, the degree of polymerization (n) of the repeating units derived from DEGMA was 31, and the degree of polymerization (p) of the repeating units derived from monomer EHMA was 11.

[0156] According to the method described in Example 1, the polymer P3 provided in Example 3 was prepared into a pigment dispersion. The initial viscosity η0 of the pigment dispersion in Example 3 was measured to be 4.334 cps, and the viscosity η1 after standing at room temperature for one week was 4.300 cps. The calculated viscosity change rate was -0.7%, which is much less than 5% in absolute terms. This indicates that the pigment dispersion in Example 3 has good stability, and polymer P3 has good dispersing ability for organic pigments.

[0157] Example 4

[0158] A polymer P4 differs from the preparation method of polymer P1 in Example 1 in that: in step (1), the two monomers and chain transfer agent are different from those in Example 1; CPDB is replaced with 9.987g of 2-[(dodecylthiocarbamate)thio]propionic acid (DoPAT); EHMA is replaced with 110.419g of isooctyl acrylate (EHA); and DEGMA is replaced with 166.485g of ethoxyethoxyethyl acrylate (EOEOEA, chemical formula CH2=CH-COOCH2CH2OCH2CH2OCH2CH3); in addition, the amount of AIBN is 1.4056g and the amount of 1,4-dioxane is 432.444g; in step (2), DMAEMA is replaced with dimethylaminoethyl acrylate (N,N-Dimethylaminoethyl acrylate). Acrylate (DMAEA), the amount of which is 53.110g, AIBN is 1.4056g, and 1,4-dioxane is 81.770g.

[0159] The structural formula of polymer P4 can be represented as follows:

[0160]

[0161] The weight-average molecular weight (Mw) of polymer P4, measured by GPC, was 10600 g / mol, and the molecular weight distribution (PDI) was 1.09. Combined with the NMR results of this polymer, it was found that the degree of polymerization (m) of the repeating units derived from monomer DMAEA was 15, the degree of polymerization (n) of the repeating units derived from monomer EOEOEA was 20, and the degree of polymerization (p) of the repeating units derived from monomer EHA was 21.

[0162] According to the method described in Example 1, the polymer P4 provided in Example 4 was prepared into a pigment dispersion. The initial viscosity η0 of the pigment dispersion in Example 4 was measured to be 7.535 cps, and the viscosity η1 after standing at room temperature for one week was 7.36 cps. The calculated viscosity change rate was -2.3%, whose absolute value was much less than 5%. This indicates that the pigment dispersion in Example 4 has good stability, and polymer P4 has good dispersing ability for organic pigments.

[0163] Example 5

[0164] A polymer P5 differs from the preparation method of polymer P1 in Example 1 in that: in step (1), DEGMA is not used, and EHMA is replaced with 269.829g of tert-butyl methacrylate (TBMA). In addition, the amount of CPDB is 7.368g, the amount of AIBN is 1.6400g, and the amount of 1,4-dioxane is 418.255g; in step (2), the amount of DMAEMA is 62.803g, the amount of AIBN is 1.6400g, and the amount of 1,4-dioxane is 96.66g.

[0165] The weight-average molecular weight (Mw) of polymer P5, measured by GPC, was 10200 g / mol, and the molecular weight distribution (PDI) was 1.04. Combined with the NMR results of this polymer, the degree of polymerization (m) of the repeating units derived from monomer DMAEA was 12, and the degree of polymerization (p) of the repeating units derived from monomer BMA was 57.

[0166] According to the method described in Example 1, the polymer P5 provided in Example 5 was prepared into a pigment dispersion. The initial viscosity η0 of the pigment dispersion in Example 5 was measured to be 5.65 cps, and the viscosity η1 after standing at room temperature for one week was 5.64 cps. The calculated viscosity change rate was -0.1%, and its absolute value was much less than 5%, indicating that the pigment dispersion in Example 5 has good stability and that polymer P5 has good dispersing ability for organic pigments.

[0167] Comparative Example 1

[0168] A polymer CP1, which differs from the preparation method of polymer P1 in Example 1 in that:

[0169] In step (1), the chain transfer agent CPDB is replaced with DoPAT, and the amount used is 5.745 g; 2-ethylhexyl methacrylate (EHMA) is replaced with butyl methacrylate (BMA), and the amount used is 61.793 g; DEGMA is replaced with polyethylene glycol methyl ether methacrylate (PEGA, whose structural formula is...). (t is an integer between 12 and 15), the amount of PEGA used is 244.258g; in addition, the amount of AIBN used is 0.8087g, and the amount of 1,4-dioxane used is 468.907g;

[0170] In step (2), the amount of DMAEA used is 28.204g, the amount of AIBN used is 0.8087g, and the amount of 1,4-dioxane used is 43.520g.

[0171] The polymer CP1 prepared in Comparative Example 1, measured by GPC, had a weight-average molecular weight (Mw) of 20700 g / mol and a molecular weight distribution (PDI) of 1.10. Combined with the NMR results of this polymer, it was found that the degree of polymerization (m) of the repeating units derived from monomer DMAEA was 12, the degree of polymerization (n) of the repeating units derived from PEGA was 31, and the degree of polymerization (p) of the repeating units derived from monomer BMA was 20.

[0172] According to the method described in Example 1, the polymer CP1 provided in Comparative Example 1 was used to prepare a pigment dispersion. The initial viscosity η0 of the pigment dispersion in Comparative Example 1 was measured to be 15.04 cps, and it solidified after standing at room temperature for one week. This indicates that the pigment dispersion using the polymer provided in Comparative Example 1 as a pigment dispersant has extremely poor stability.

[0173] A comparison of the stability test results of the pigment dispersions in Comparative Example 1 and Example 4 reveals that when preparing the polymer as a pigment dispersant, if the alkyl methacrylate monomer used is a linear alkyl methacrylate or the polyether in the methacrylate with a polyether structure is a macromolecular structure, the polymer will have a poor dispersion effect on the pigment.

[0174] Comparative Example 2

[0175] A polymer CP2 differs from the preparation method of polymer P1 in Example 1 in that: in step (1), methyl methacrylate (MMA) is used instead of 2-ethylhexyl methacrylate (EHMA), and the amount of MMA is 113.017g; in addition, the amount of CPDB is 5.949g, the amount of DEGMA is 61.879g, the amount of AIBN is 1.324g, and the amount of 1,4-dioxane is 423.254g; in step (2), the amount of DMAEMA is 59.155g, the amount of AIBN is 1.324g, and the amount of 1,4-dioxane is 90.720g.

[0176] The polymer prepared in Comparative Example 2, measured by GPC, had a weight-average molecular weight (Mw) of 12700 g / mol and a molecular weight distribution (PDI) of 1.14. Combined with the NMR results of this polymer, it was found that the degree of polymerization (m) of the repeating units derived from the monomer DMAEMA was 14, the degree of polymerization (n) of the repeating units derived from DEGMA was 32, and the degree of polymerization (p) of the repeating units derived from the monomer MMA was 42.

[0177] According to the method described in Example 1, the polymer CP2 provided in Comparative Example 2 was used to prepare a pigment dispersion. The initial viscosity η0 of the pigment dispersion in Comparative Example 2 was measured to be 12.530 cps, and the viscosity η1 after standing at room temperature for one week was 27.58 cps, with a calculated viscosity increase rate of 120.1%. This indicates that the polymer provided in Comparative Example 5 has a poor dispersion effect on pigments, and the pigment dispersion using it as a color dispersant has extremely poor stability.

[0178] A comparison between Comparative Example 2 and Example 1 reveals that, when the molecular weight of the polymers is similar and the structures of other repeating units are identical, the polymer exhibits poor pigment dispersion when the alkyl group in the alkyl methacrylate is a straight-chain alkyl group rather than a branched alkyl group. This indicates that sterically hindered branched alkyl groups contribute to pigment dispersion.

[0179] In addition, after the pigment dispersions of the above embodiments and comparative examples were coated on a glass substrate to form films, they were immersed in an alkaline developing solution (specifically, a 2.38 wt% TMAH aqueous solution) for 60 seconds to observe the dissolution state of the film.

[0180] in, Figure 7 The images show photographs of the dried film formed using the pigment dispersion of Example 1 before and after immersion in an alkaline developing solution; where (a) is the inset before immersion and (b) is the inset after immersion. Figure 7 It can be seen that the dried film layer formed by the pigment dispersion in Example 1 can be well dissolved after being soaked in alkaline developing solution, which is beneficial for the use of the pigment dispersion in the patterning composition to form a color resist pattern that is consistent with the expected pattern.

[0181] Furthermore, the dried film layers formed by the pigment dispersions in Examples 2-4 and Comparative Examples 1-2 were completely dissolved after immersion in alkaline developing solution; however, the dried film layer formed by the pigment dispersion in Example 5 did not dissolve after immersion in alkaline developing solution. From the alkaline solubility test results of the pigment dispersions in Example 5 and the aforementioned Examples 1-4, it can be seen that when the polymer used as a pigment dispersant contains acrylate repeating units with alkyl-terminated ethoxy repeating units, the polymer can also exhibit good alkaline solubility.

[0182] The above description merely illustrates exemplary embodiments of this application, and while the description is specific and detailed, it should not be construed as limiting the scope of this patent application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims.

[0183] It should be understood that the use of "first," "second," and various numerical designations in this document is for descriptive convenience only and is not intended to limit the scope of this application. In this application, "and / or" describes the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, or B existing alone, where A and B can be singular or plural. The character " / " generally indicates that the preceding and following related objects have an "or" relationship.

[0184] In the description of this application, unless otherwise stated, "multiple" means two or more. "At least one" means one or more. "At least one of the following" or similar expressions refer to any combination of these items, including any combination of single or multiple items. For example, "at least one of a, b, or c", or "at least one of a, b, and c", can both mean: a, b, c, ab (i.e., a and b), ac, bc, or abc, where a, b, and c can be single or multiple.

[0185] Furthermore, the numerical range indicated by "-" in this application refers to the range including the values ​​before and after "-", which are respectively taken as the minimum and maximum values. In this application, expressions regarding parameter ranges, such as "greater than or equal to (≥)", "less than or equal to (≤)", "above", and "below", all include the stated number. The numerical values ​​and ranges involved in the embodiments of this application are approximate values, and may have a certain range of errors due to the influence of manufacturing processes / testing methods, etc. These errors are negligible to those skilled in the art.

Claims

1. A polymer, characterized in that, The polymer has a structure shown in formula (I): In formula (I), co represents a copolymer, b represents a block, R4-C(=S)-S- and -R5 constitute a chain transfer agent for RAFT reaction; each R is independently selected from a hydrogen atom or a methyl group, R1 is independently selected from a C1-C4 alkyl group terminated with a C1-C4 alkoxy group; R2 is independently selected from a halogenated or unsubstituted branched alkyl group; R3 independently includes an alkyl group substituted with a cyclic amine group, a chain amine group, or a quaternized group thereof; 0≤n≤60, 0≤p≤60, and 40≤n+p≤60, 5≤m≤25. 1-4 1-4 ethoxy repeat units of an alkyl group; R2 is independently selected from a halogenated or unsubstituted branched alkyl group; R3 independently includes an alkyl group substituted with a cyclic amine group, a chain amine group, or a quaternized group thereof; 0≤n≤60, 0≤p≤60, and 40≤n+p≤60, 5≤m≤25.

2. The polymer of claim 1, wherein The halogenated or unsubstituted branched alkyl has 3-20 carbon atoms.

3. The polymer according to claim 1 or 2, wherein R3comprises C 2-4 alkyl, wherein each alkyl of the dialkylamino group is independently selected from substituted or unsubstituted C 1-6 alkyl.

4. The polymer according to any one of claims 1 to 3, wherein R4 is independently selected from phenyl, dodecyl or dodecyl with a sulfide bond; R5 is independently selected from one of -CN, -CH2CN, -C(CH3)2-CN, -CH2-COOH, -CH2-CH2-COOH, -CH(CH3)-COOH, -C(CH3)2-COOH, -C(CH3)(CN)-CH2CH2COOH, -C(CH3)2-Ph.

5. The polymer according to any of claims 1 to 4, wherein n is an integer between 10 and 35, and p is an integer between 8 and 25.

6. The polymer according to any one of claims 1 to 5, wherein n>0, p>0, n+p is an integer between 40 and 55.

7. The polymer according to any one of claims 1 to 6, wherein m is an integer between 8 and 16.

8. The polymer according to any one of claims 1 to 7, wherein The molecular weight distribution index of the polymer is less than 1.

14.

9. Use of the polymer according to any one of claims 1-8 in the preparation of a pigment dispersant, a pigment dispersion liquid, a pigment-containing photosensitive composition, or a color resist.

10. A pigment dispersion liquid characterized by comprising: A pigment, a pigment dispersant, and a solvent are included, wherein the pigment dispersant includes the polymer according to any one of claims 1-8.

11. The pigment dispersion liquid according to claim 10, wherein The mass of the polymer is 10%-30% of the mass of the pigment.

12. The pigment dispersion liquid according to claim 10 or 11, characterized by, The solvent includes one or more of an ester solvent, an ether solvent, and a ketone solvent.

13. The pigment dispersion liquid according to any one of claims 10 to 12, wherein The pigment dispersant further includes other dispersants.

14. The pigment dispersion liquid according to any one of claims 10 to 13, wherein The mass percentage of the pigment in the pigment dispersion liquid is in the range of 10%-85%.

15. The pigment dispersion liquid according to any one of claims 10 to 14, wherein The initial viscosity of the pigment dispersion liquid at room temperature is below 10 mPa·s.

16. The pigment dispersion liquid according to any one of claims 10 to 15, wherein The viscosity change rate of the pigment dispersion liquid after standing at room temperature for 1 week is below 5% in absolute value.

17. The pigment dispersion liquid according to any one of claims 10 to 16, wherein The pigment includes one or more of a red pigment, a green pigment, a blue pigment, a yellow pigment, an orange pigment, and a purple pigment.

18. A patterning composition characterized in that, A photosensitive resin, a photopolymerization monomer, and a photoinitiator are included.

19. The patterning composition of claim 18, wherein, The patterning composition further includes an auxiliary agent, which includes one or more of a leveling agent, a defoaming agent, an adhesion promoter, and an antioxidant.

20. A patterned color resist film, characterized in that, Formed by a patterning process of the patterning composition according to any one of claims 18-19.

21. A color filter, characterized by A substrate and a color resist layer disposed on the substrate are included, and the color resist layer includes at least one of the patterned color resist film according to claim 20.

22. A method of preparing a polymer, characterized by, The following steps are included: (1) polymerizing a first monomer shown in formula (i1) and / or a second monomer shown in formula (i2) in an organic solvent in the presence of a chain transfer agent with a structure of R1-C(=S)-S-R2 and an initiator, to obtain an intermediate mother liquor; (2) adding a mixture containing a third monomer shown in formula (i3) and an initiator to the intermediate mother liquor, and continuing the polymerization reaction to obtain a polymer; wherein each R is independently selected from a hydrogen atom or a methyl group, R1is independently selected from 1-4 ethoxy repeat units ending in a methyl or ethyl group; R2is independently selected from a halogenated or unsubstituted branched alkyl group; R3independently comprises an alkyl group substituted with a cyclic amine group, a chain amine group, or a quaternized version thereof; the polymer having a degree of polymerization n of the first repeat unit derived from the first monomer, a degree of polymerization p of the second repeat unit derived from the second monomer independently in the range of 0-60, and n+p in the range of 40-60, and a degree of polymerization m of the third repeat unit derived from the third monomer in the range of 5-25.

Images