Polymerizable liquid crystal mixture, polymerizable composition, and phase difference film

Abstract

The invention provides a polymerizable liquid crystal mixture not prone to precipitation, a polymerizable composition containing the polymerizable liquid crystal mixture and a phase difference film, and relates to the technical field of optical material preparation. The polymerizable liquid crystal mixture contains a polymerizable liquid crystal compound A and a polymerizable liquid crystal compound B having different structures. The phase difference film prepared from the polymerizable composition is not easy to crystallize in the manufacturing process, has good surface morphology, and shows excellent reverse wavelength dispersibility.

Description

Technical Field

[0001] This application relates to the field of optical material preparation technology, and in particular to a polymerizable liquid crystal mixture, a polymerizable composition, and a phase difference film. Background Technology Optical films are a key component in modern display technology, affecting display brightness, sharpness, and viewing angle distortion. Among them, inverse wavelength dispersion (IRD) films, due to their unique optical properties, are widely used in polarizers of liquid crystal displays (LCDs) and organic light-emitting diode (OLEDs) for anti-reflection and viewing angle compensation. IRD generally refers to the relationship between the phase difference and wavelength at a positive viewing angle. It is typically expressed as R450 at 450 nm and R550 at 550 nm satisfying the condition: R450 / R550 < 1.0.

[0002] Phase retardation films achieving reverse wavelength dispersion currently primarily utilize liquid crystal polymer materials, leveraging the material's birefringence to create a phase difference. Mainstream, these liquid crystal polymers typically use a coating solution as a precursor, containing one or more polymerizable liquid crystal compounds, initiators, leveling agents, solvents, etc. To ensure the liquid crystals achieve a specific orientation, a functional alignment layer is also required on the substrate. After coating the precursor solution onto the substrate containing the alignment layer, a heating and drying process is performed. Once the solvent evaporates, the liquid crystals form a liquid crystal phase with a specific orientation (i.e., "alignment") under certain temperature conditions. Subsequently, a polymerization reaction is initiated by ultraviolet light to fix the liquid crystal alignment, resulting in an anisotropic polymer film with well-aligned optical properties and phase difference—the phase retardation film.

[0003] Therefore, extensive research has been conducted on polymeric liquid crystal compounds capable of forming retardation films exhibiting reverse wavelength dispersion and polymeric compositions containing them. Polymeric liquid crystal compounds capable of constituting retardation films exhibiting reverse wavelength dispersion are known, as described in invention patents CN111201220B, CN101838264B, CN110891945B, CN105384723B, and CN119592332B.

[0004] The inventors have discovered through research that a phase retardation film exhibiting reverse wavelength dispersion can be prepared using the polymeric liquid crystal compound or its analogue described in the aforementioned patent. However, due to their molecular structure, this type of polymeric liquid crystal compound is prone to precipitation in various solvents, and during the coating process, as the solvent evaporates, problems such as crystallization and surface morphology defects easily occur on the film surface.

[0005] Therefore, there is an urgent need for a polymeric liquid crystal material that is not easily precipitated in solvents and whose surface is not prone to crystallization and surface morphology defects during the manufacturing of phase difference films with excellent reverse wavelength dispersion. Summary of the Invention

[0006] In view of the problems in the prior art where polymeric liquid crystal compounds are prone to precipitation in various solvents due to their molecular structure, and the easy crystallization and surface morphology defects on the film surface during the coating process due to solvent evaporation, the purpose of this application is to provide a polymeric liquid crystal mixture that is not prone to precipitation and a polymeric composition containing the polymeric liquid crystal mixture. The phase difference film prepared by the polymeric composition exhibits excellent reverse wavelength dispersibility while being less prone to crystallization and having a better surface morphology, thereby solving the problems existing in the prior art.

[0007] To solve the above-mentioned technical problems, this application is implemented as follows: According to a first aspect of this application, a polymerizable liquid crystal mixture is provided, the polymerizable liquid crystal mixture comprising polymerizable liquid crystal compounds A and B with different structures, wherein polymerizable liquid crystal compound A is a compound represented by the following formula (1), and polymerizable liquid crystal compound B is a compound represented by the following formula (2). (1) (2) In the above equations (1) to (2), G 1 G represents the group represented by the following formula (G-1), where G 2 Selected from the groups represented by the following formulas (G-1) to (G-3):

[0008] Where * indicates the bonding position. M 1 M 2 M 3 M 4 C 1 and C 2 Each can be independently represented as -OCH2-, -CH2O-, -O-CO-O-, -COO-, or -OCO-. D 1 and D 2 Each of the following groups can be represented independently: , B 1 and B 2 Each of the following formulas (B-1) represents a group independently:

[0009] A 1 and A 2 Each can independently represent a single bond, -OCH2-, -CH2O-, -O-CO-O-, -COO-, -OCO-, or -O-. SP 1 and SP 2 Each can independently represent a straight-chain or branched alkylene group having 1 to 20 carbon atoms, wherein any one -CH2- or multiple non-adjacent -CH2- groups can be independently replaced by -O-, -COO-, -OCO-, or -O-CO-O-. L 1 and L 2 Each of these groups independently represents a polymerizable group, which is selected from the groups represented by formula (L-1) or formula (L-2) below. , Q represents a straight-chain or branched alkyl group with 1 to 20 carbon atoms, or a cycloalkyl group with 3 to 8 carbon atoms. W 1 express W 1 Hydrogen atoms at any position on the aromatic ring can be independently substituted by one or more substituents U, where U is selected from straight-chain or branched alkyl, methoxy, or ethoxy groups having 1 to 20 carbon atoms. W 2 It is represented by the following formula (W-1), J 1 -T 1 -*(W-1) In the above formula (W-1), T 1 This refers to a straight-chain or branched alkylene group having 1 to 20 carbon atoms, wherein any one -CH2- or multiple non-adjacent -CH2- groups can be independently replaced by -O-, -COO-, -OCO-, -O-CO-O-, or -C≡C-. J 1 This represents a hydrogen atom or a polymerizable group, wherein the polymerizable group is selected from the groups represented by formula (L-1) or formula (L-2) above. m and n each independently represent integers from 0 to 3. V 1 and V 2 Each independently represents a straight-chain or branched alkyl, cyano, methoxy, ethoxy, methoxycarbonyl, or ethoxycarbonyl group having 1 to 10 carbon atoms. When multiple V groups are present... 1 and / or V 2 At that time, multiple V 1 They can be the same or different, multiple Vs 2They may be the same or different.

[0010] Optionally, J 1 Selected from the groups represented by formula (L-1) or formula (L-2).

[0011] Alternatively, in the above formula (W-1), T 1 Selected from -CH2CH2OCH2CH2OCH2CH2- or -CH2CH2OCH2CH2-.

[0012] Optionally, the parent nucleus of the polymerizable liquid crystal compound A The ClogP value is less than 5, indicating that the parent nucleus of the polymeric liquid crystal compound B... The ClogP value is greater than or equal to 5.

[0013] Optionally, the polymerizable liquid crystal compound A is selected from the following structures:

[0014] .

[0015] Optionally, the polymerizable liquid crystal compound B is selected from the following structures:

[0016]

[0017] .

[0018] Optionally, the polymeric liquid crystal mixture comprises 5 to 80 parts by weight of the polymeric liquid crystal compound A and 10 to 90 parts by weight of the polymeric liquid crystal compound B.

[0019] According to a second aspect of this application, a polymerizable composition is provided comprising the polymerizable liquid crystal mixture described in the first aspect of this application.

[0020] Optionally, the polymerizable composition further comprises a polymerizable liquid crystal compound N; The polymerizable liquid crystal compound N is selected from the following structures: .

[0021] Optionally, the polymeric liquid crystal composition comprises, by weight, 40 to 99.9 parts of the polymeric liquid crystal mixture and 0.1 to 60 parts of the polymeric liquid crystal compound N.

[0022] According to a third aspect of this application, a phase retardation film is provided, the phase retardation film comprising a polymer product polymerized from the polymerizable composition described in the second aspect of this application.

[0023] Optionally, the phase difference R450 at a wavelength of 450 nm and the phase difference R550 at a wavelength of 550 nm satisfy the following condition: R450 / R550 < 1.0.

[0024] The technical solution adopted in this invention can achieve the following beneficial effects: This application provides a polymerizable liquid crystal mixture that is not easily precipitated in a solvent, and a polymerizable composition containing the polymerizable liquid crystal mixture. This allows the use of a polymerizable composition containing the polymerizable liquid crystal mixture provided in this application to minimize crystallization during the fabrication of a retardation film, resulting in a better surface morphology and an excellent reverse wavelength dispersion in the fabricated retardation film. Therefore, by using the liquid crystal mixture provided in this application, a retardation film with fewer crystallization and surface morphology defects and excellent reverse wavelength dispersion can be prepared. Detailed Implementation

[0025] To make the objectives, technical solutions, and advantages of this invention clearer, the technical solutions of this invention will be clearly and completely described below in conjunction with specific embodiments. Obviously, the described embodiments are only a part of the embodiments of this invention, and not all of them. Based on the embodiments of this invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this invention.

[0026] [Polymerizable liquid crystal mixture] In one embodiment of this application, a polymerizable liquid crystal mixture is provided, comprising two polymerizable liquid crystal compounds A and B with different structures, wherein polymerizable liquid crystal compound A is a compound represented by the following formula (1), and polymerizable liquid crystal compound B is a compound represented by the following formula (2): (1) (2), In the above equations (1) to (2), G 1 G represents the group represented by the following formula (G-1), where G 2 Selected from the groups represented by formulas (G-1) to (G-3) below.

[0027]

[0028] In this context, * indicates the bonding position.

[0029] From the perspective of suppressing precipitation, the parent nucleus of polymeric liquid crystal compound A is preferred. The ClogP value is less than 5, indicating that the parent nucleus of the polymeric liquid crystal compound B... The ClogP value is greater than or equal to 5. The CLogP value is obtained by calculating the logarithm of the partition coefficient of the solute in the water / 1-octanol system, for example, by known methods such as ChemDraw 23.0.1 (made by Cambridge Soft).

[0030] M 1 M 2 M 3 M 4 C 1 and C 2 Each can be independently represented as -OCH2-, -CH2O-, -O-CO-O-, -COO-, or -OCO-.

[0031] D 1 and D 2 Each of the following groups can be represented independently: .

[0032] B 1 and B 2 Each of the following formulas (B-1) represents a group independently: .

[0033] A 1 and A 2 Each can independently represent a single bond, -OCH2-, -CH2O-, -O-CO-O-, -COO-, -OCO-, or -O-.

[0034] SP 1 and SP 2 Each independently represents a straight-chain or branched alkylene group having 1 to 20 carbon atoms, wherein any one of -CH2- or multiple non-adjacent -CH2- groups can be independently replaced by -O-, -COO-, -OCO- or -O-CO-O-.

[0035] L 1 and L 2 Each of these groups independently represents a polymerizable group, which is selected from the groups represented by the following formula (L-1) or formula (L-2): .

[0036] Q represents a hydrogen atom, a straight-chain or branched alkyl group with 1 to 20 carbon atoms, or a cycloalkyl group with 3 to 8 carbon atoms. From the perspective of raw material availability and ease of synthesis, it is preferable that Q represents a hydrogen atom.

[0037] W 1 express W 1 Each hydrogen atom at any position on the aromatic ring can be independently replaced by one or more substituents U, where U is selected from straight-chain or branched alkyl, methoxy, or ethoxy groups having 1 to 20 carbon atoms.

[0038] W 2 It can be represented by the following formula (W-1): J 1 -T 1 -*(W-1)

[0039] In the above formula (W-1), T 1 This refers to a straight-chain or branched alkylene group having 1 to 20 carbon atoms, wherein any one -CH2- or multiple non-adjacent -CH2- groups can be independently replaced by -O-, -COO-, -OCO-, -O-CO-O-, or -C≡C-. From the perspective of suppressing precipitation, T is preferred. 1 It represents -CH2CH2OCH2CH2OCH2CH2- or -CH2CH2OCH2CH2-.

[0040] J 1 This represents a hydrogen atom or a polymeric group, wherein the polymeric group is selected from the groups represented by formula (L-1) or formula (L-2) above. From the perspective of suppressing precipitation, as a preferred embodiment, J... 1 The group is selected from the group represented by formula (L-1) or formula (L-2).

[0041] m and n each independently represent integers from 0 to 3.

[0042] V 1 and V 2 Each independently represents a straight-chain or branched alkyl, cyano, methoxy, ethoxy, methoxycarbonyl, or ethoxycarbonyl group having 1 to 10 carbon atoms. When multiple V groups are present... 1 and / or V 2 At that time, multiple V 1 They can be the same or different; multiple Vs 2 They can be the same or they can be different.

[0043] Specifically, as polymerizable liquid crystal compound A represented by general formula (1), compounds represented by the following formulas (R-1) to (R-14) can be cited:

[0044] .

[0045] Specifically, as polymerizable liquid crystal compound B represented by general formula (2), examples include compounds represented by formulas (R-1) to (R-14) above or formulas (R-15) to (R-16) below: .

[0046] There are no particular limitations on the method of manufacturing the compounds represented by formulas (1) to (2) of the present invention. They can be manufactured by appropriately combining known organic synthesis reactions (such as nucleophilic substitution reactions, esterification reactions, condensation reactions, Schiff base formation reactions, deprotection reactions, etc.) recorded in Organic Reactions, Organic Syntheses, Comprehensive Organic Synthesis, etc., according to their structures.

[0047] The polymerizable liquid crystal compound A and polymerizable liquid crystal compound B of the present invention can be mixed in a certain mass fraction to form a polymerizable liquid crystal mixture. In one embodiment, the polymerizable liquid crystal mixture comprises 5 to 80 parts of polymerizable liquid crystal compound A and 10 to 90 parts of polymerizable liquid crystal compound B by mass fraction. For example, the mass fraction of polymerizable liquid crystal compound A in the polymerizable liquid crystal mixture can be 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80 parts or any value between these values, and the mass fraction of polymerizable liquid crystal compound B in the polymerizable liquid crystal mixture can be 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90 parts or any value between these values.

[0048] [Polymerizable Composition] The polymerizable composition of the present invention is a polymerizable composition containing the above-described polymerizable liquid crystal mixture. In addition to the polymerizable liquid crystal mixture of the present invention, the polymerizable composition may also contain the polymerizable liquid crystal compound N, photopolymerization initiator, stabilizer, other additives, and solvent, as described later.

[0049] [Polymerizable liquid crystal compound N] In addition to polymeric liquid crystal compounds A and B in the polymeric liquid crystal mixtures of the present invention described above, the polymeric composition of the present invention may also contain other polymeric liquid crystal compounds N that do not exhibit reverse wavelength dispersion, thereby adjusting wavelength dispersion, increasing crosslinking density, adjusting refractive index, and reducing cost. Specifically, compounds represented by the following formulas (N-1) to (N-17) are preferred:

[0050] .

[0051] When the polymerizable composition provided by the present invention contains the above-mentioned polymerizable liquid crystal compound N, the mass fractions M of polymerizable liquid crystal compound A, polymerizable liquid crystal compound B, and polymerizable liquid crystal compound N in the polymerizable composition provided by the present invention are... A M B M N Satisfy: M A +M B +M N =100 copies, and M A +M B ≥40 servings, M A +M B≤99.9 parts. Wherein, the mass parts (M) of the polymeric liquid crystal compound A A The mass fraction (M) of the polymeric liquid crystal compound B is 5 to 80 parts. B The mass fraction of the polymeric liquid crystal composition N is 10-90 parts, and the mass fraction of N (M) is... N The dosage ranges from 0.1 to 60 parts.

[0052] [Photopolymerization initiator] To form a crosslinked network through photoinitiated polymerization, a photoinitiator is generally required in the polymerizable composition. Examples of suitable photoinitiators for this invention include benzophenones, acetophenones, and benzoyl ketals. Furthermore, some brand-name initiators such as BASF OXE-01, OXE-02, OXE-03, OXE-04, and OXE-05 can also be added as photoinitiators. One photoinitiator can be used, or two or more photoinitiators can be used simultaneously. Relative to the polymerizable composition provided in this application, the photoinitiator accounts for 0.1% to 10% by mass, preferably 0.2% to 5% by mass, and more preferably 1% to 3% by mass, of the total mass of the polymerizable composition.

[0053] [Stabilizer] To improve its storage stability, a stabilizer is generally required in the polymeric composition. Suitable stabilizers for this invention include, for example, hydroquinones, hydroquinone monoalkyl ethers, tert-butylcatechols, pyrogallols, thiophenols, nitro compounds, β-naphthylamines, β-naphthols, and nitroso compounds. The amount of stabilizer added relative to the total mass of the polymeric composition is preferably 0.005% to 1% by mass, more preferably 0.01% to 0.8% by mass, and even more preferably 0.02% to 0.5% by mass. One stabilizer can be used, or two or more stabilizers can be used simultaneously. 2,6-Di-tert-butyl-p-cresol (BHT) is preferably used as a stabilizer.

[0054] [Other adjuvants] In actual coating production processes, other additives can be added as needed to ensure solution leveling, photocrosslinking efficiency, etc. For example, additives suitable for the compositions of the present invention may include one or more combinations of leveling and defoaming agents and chain transfer agents. The leveling and defoaming agents may be at least one of the following: BYK-300, BYK-306, BYK-358, BYK-354, BYK-515, BYK-3560, BYK-3566 (purchased from BYK Corporation); MEGAFACE F-554, F-556 (purchased from DIC Corporation); and Zonyl FS-520, Zonyl 8857A (purchased from DuPont Corporation). The amount of additive used is preferably 0.005% to 5% by mass, more preferably 0.01% to 3% by mass, and even more preferably 0.02% to 1% by mass, relative to the total mass of the polymerizable composition.

[0055] [solvent] In actual coating production processes, solvents are required to facilitate the coating process. Solvents suitable for the compositions of this invention mainly include benzenes, ketones, ethers, esters, halogenated hydrocarbons, and highly polar solvents. Benzene solvents mainly include: toluene, ethylbenzene, xylene, chlorobenzene, and anisole; ketone solvents mainly include: acetone, methyl ethyl ketone, 3-pentanone, cyclopentanone, cyclohexanone, and isophorone; ether solvents mainly include: 1,4-dioxane and tetrahydrofuran; ester solvents mainly include: ethyl acetate, butyl acetate, and propylene glycol methyl ether acetate; halogenated hydrocarbon solvents mainly include: dichloromethane, chloroform, and 1,2-dichloroethane; highly polar solvents mainly include: methanol, ethanol, isopropanol, n-butanol, tert-butanol, propylene glycol methyl ether, dimethyl sulfoxide, N,N-dimethylformamide, N,N-dimethylacetamide, N-methylpyrrolidone, N-ethyl-2-pyrrolidone, ethanolamine, and acetonitrile. You can use one solvent alone, or you can use two or more solvents at the same time.

[0056] [Phase difference film] The phase retardation film of the present invention is formed by coating the polymeric composition solution described in the present invention onto a glass substrate having an alignment layer, followed by drying and photocuring. Therefore, the phase retardation film of the present invention comprises a polymer product formed by polymerizing the above-described polymeric composition. The phase difference R450 at a wavelength of 450 nm and the phase difference R550 at a wavelength of 550 nm satisfy the following condition: R450 / R550 < 1.0.

[0057] Example The present invention will be further described below with reference to specific embodiments, but the present invention is not limited to the following embodiments.

[0058] [Manufacturing of polymeric liquid crystal compounds] The following polymerizable liquid crystal compounds R-1, R-9, R-12, R-13, R-14, R-15 and R-16 are manufactured according to the methods described in invention patent CN119592332B, etc.

[0059]

[0060]

[0061]

[0062]

[0063] [Preparation of polymeric liquid crystal mixtures] The polymeric liquid crystal compounds A and B were mixed in the mass fractions shown in Table 1 below to obtain the polymeric liquid crystal mixtures represented in Examples 1 to 10.

[0064] Table 1

[0065] Note: "-" in Table 1 indicates that no corresponding liquid crystal compound was added.

[0066] [Precipitation] The precipitation properties of the liquid crystal mixtures / compounds represented in Examples 1 to 10 and Comparative Examples 1 to 4 were determined using the methods shown below. The results are shown in Table 2 below.

[0067] Specifically, weigh 1 g of the liquid crystal mixture / compound and 4 g of cyclohexanone into a 30 mL sample vial. Heat and sonicate thoroughly until the solution is clear and transparent. Let stand at room temperature and observe for precipitation.

[0068] A: No precipitation after 168 hours B: Precipitation within 168 hours C: Precipitation within 72 hours D: Precipitation within 24 hours Table 2

[0069] [Wavelength Dispersion] Photoaligning agent HSPA-252B (manufactured by Osaka Organics) was uniformly coated onto a glass surface using a spin coater (2300 rpm, 10 s). Drying was performed at 120 °C. After cooling to room temperature, the surface was irradiated with 10 mJ of polarized ultraviolet light at 313 nm to obtain a glass substrate with an alignment layer. On the glass substrate with the alignment layer, the polymerizable composition solution described in Table 3 was uniformly coated onto each substrate using a spin coater (600 rpm, 30 s), and dried at 100 °C to evaporate the solvent. Subsequently, the substrate was cooled to room temperature, and the film surface containing the composition was irradiated with a mercury lamp under a nitrogen atmosphere with a total energy of 1500 mJ / cm². 2 That is, to obtain a phase difference film.

[0070] Table 3

[0071] For the fabricated retardation film, the phase difference at various wavelengths was measured using an Axoscan polarimeter. The phase difference R450 at 450 nm and R550 at 550 nm were recorded. The ratio R450 / R550 was calculated and evaluated according to the following criteria. The results are shown in Table 4 below, where a smaller R450 / R550 ratio indicates better inverse wavelength dispersion.

[0072] A: R450 / R550 is less than or equal to 0.84 B: R450 / R550 is greater than 0.84 and less than or equal to 0.87 C: R450 / R550 is greater than 0.87 and less than or equal to 0.9 D: R450 / R550 is greater than 0.9 [Surface Morphology] The fabricated phase retardation films were visually examined using an optical microscope to confirm their surface morphology, and evaluated according to the following criteria. The results are shown in Table 4 below.

[0073] A: Almost no bright spots or streak-like defects were observed. B: Although bright spots and streak-like defects were observed in some areas, there are no problems in actual use. C: Many bright spots and striped defects D: Bright spots and striped defects across the entire surface [crystallization] The fabricated phase retardation films were visually examined using an optical microscope to confirm the crystallization pattern on the screen, and evaluated according to the following criteria. The results are shown in Table 4 below.

[0074] A: No crystallization B: Localized small-scale crystallization C: Extensive crystallization D: Dense crystallization across the entire surface Table 4

[0075] Note: "-" in Table 4 indicates that no corresponding liquid crystal compound was added.

[0076] The results shown in Tables 2 and 4 reveal that all Comparative Examples 1-4 (liquid crystal compounds 1-4) received a "D" rating for precipitation (precipitation within 24 hours), indicating that polymeric liquid crystal compound A and polymeric liquid crystal compound B alone readily precipitate in the solvent. The phase retardation films prepared in Comparative Examples 9-12 received a "D" rating for both surface morphology and crystallinity (bright spots across the entire surface, stripe defects, and dense crystallization across the entire area). This demonstrates that neither polymeric liquid crystal compound A nor polymeric liquid crystal compound B alone can form a practically valuable optical thin film; the film layer exhibits severe defects that significantly affect the optical performance of the display. In contrast, the polymeric liquid crystal mixture provided by this invention achieves technical effects far exceeding expectations in terms of precipitation, post-film surface morphology, and crystallinity, and also exhibits excellent reverse wavelength dispersion after film formation. Specifically, compared to polymerizable liquid crystal compound A alone, the polymerizable liquid crystal mixture provided in this application exhibits significantly improved segregation properties (from grade D to grade AC), and the phase retardation film formed from the polymerizable composition containing the polymerizable liquid crystal mixture of the present invention shows significant improvements in crystallinity and surface morphology (from grade D to grade AC). Compared to polymerizable liquid crystal compound B alone, the polymerizable liquid crystal mixture also achieves a similarly significant improvement in segregation properties, post-film surface morphology, and crystallinity (from grade D to grade AC). In particular, regarding solvent segregation properties, the polymerizable liquid crystal mixture of the present invention (as in Examples 12-15) showed no segregation after 168 hours (evaluated as grade A). The difference in surface morphology and crystallinity after film formation is even more pronounced: films made from a single component (polymeric liquid crystal compound A or B) (Comparative Examples 9-12) are riddled with defects and completely crystallized (evaluated as D), possessing almost no practical value; while polymeric liquid crystal compositions containing the polymeric liquid crystal mixture of the present invention (e.g., Examples 22-25) form high-quality phase reversal films with excellent surface morphology (almost no bright spots or stripe defects observed) and no crystallization (evaluated as A). Therefore, the experimental results shown in Tables 2 and 4 clearly demonstrate that the present invention, by mixing polymeric liquid crystal compounds A and B with specific structures, achieves unexpected synergistic effects and perfectly overcomes the technical defects caused by single components.

[0077] Furthermore, comparing Examples 21-27 with Examples 28-30, it was found that when the core CLogP value of polymeric liquid crystal compound A is less than 5, while the core CLogP value of polymeric liquid crystal compound B is greater than or equal to 5, the improvement on the crystallinity and surface morphology of the phase retardation film is more significant.

[0078] In summary, this invention provides a non-precipitating polymeric liquid crystal mixture for forming a retardation film with excellent reverse wavelength dispersion. The retardation film prepared from the polymeric composition containing the polymeric liquid crystal mixture of this invention is less prone to crystallization during manufacturing and exhibits a better surface morphology.

[0079] The specific embodiments of the present invention described above are only used to illustrate the spirit and principles of the present invention, and are not intended to limit the scope of the present invention. Furthermore, after reading the description of the present invention, those skilled in the art can make various modifications, substitutions, deletions, or corrections to the technical solutions of the present invention, and these equivalent technical solutions also fall within the scope defined by the claims of the present invention.

Claims

1. A polymerizable liquid crystal mixture, characterized in that, The mixture comprises polymerizable liquid crystal compound A and polymerizable liquid crystal compound B, which have different structures. Polymerizable liquid crystal compound A is represented by the following formula (1), and polymerizable liquid crystal compound B is represented by the following formula (2). （1） （2） In the above equations (1) to (2), G 1 G represents the group represented by the following formula (G-1), where G 2 Selected from the groups represented by the following formulas (G-1) to (G-3): Where * indicates the bonding position. M 1 M 2 M 3 M 4 C 1 and C 2 Each can be independently represented as -OCH2-, -CH2O-, -O-CO-O-, -COO-, or -OCO-. D 1 and D 2 Each of the following groups can be represented independently: ， B 1 and B 2 Each of the following formulas (B-1) represents a group independently: A 1 and A 2 Each can independently represent a single bond, -OCH2-, -CH2O-, -O-CO-O-, -COO-, -OCO-, or -O-. SP 1 and SP 2 Each can independently represent a straight-chain or branched alkylene group having 1 to 20 carbon atoms, wherein any one -CH2- or multiple non-adjacent -CH2- groups can be independently replaced by -O-, -COO-, -OCO-, or -O-CO-O-. L 1 and L 2 Each of these groups independently represents a polymerizable group, which is selected from the groups represented by formula (L-1) or formula (L-2) below. ， Q represents a straight-chain or branched alkyl group with 1 to 20 carbon atoms, or a cycloalkyl group with 3 to 8 carbon atoms. W 1 express W 1 Hydrogen atoms at any position on the aromatic ring can be independently substituted by one or more substituents U, where U is selected from straight-chain or branched alkyl, methoxy, or ethoxy groups having 1 to 20 carbon atoms. W 2 It is represented by the following formula (W-1), J 1 -T 1 -*(W-1) In the above formula (W-1), T 1 This refers to a straight-chain or branched alkylene group having 1 to 20 carbon atoms, wherein any one -CH2- or multiple non-adjacent -CH2- groups can be independently replaced by -O-, -COO-, -OCO-, -O-CO-O-, or -C≡C-. J 1 This represents a hydrogen atom or a polymerizable group, wherein the polymerizable group is selected from the groups represented by formula (L-1) or formula (L-2) above. m and n each independently represent integers from 0 to 3. V 1 and V 2 Each independently represents a straight-chain or branched alkyl, cyano, methoxy, ethoxy, methoxycarbonyl, or ethoxycarbonyl group having 1 to 10 carbon atoms. When multiple V groups are present... 1 and / or V 2 At that time, multiple V 1 They can be the same or different, multiple Vs 2 They may be the same or different.

2. The polymerizable liquid crystal mixture according to claim 1, characterized in that, The parent nucleus of the polymeric liquid crystal compound A The ClogP value is less than 5, indicating that the parent nucleus of the polymeric liquid crystal compound B... The ClogP value is greater than or equal to 5.

3. The polymerizable liquid crystal mixture according to claim 1, characterized in that, The polymerizable liquid crystal compound A is selected from the following structures: 。 4. The polymerizable liquid crystal mixture according to claim 1, characterized in that, The polymerizable liquid crystal compound B is selected from the following structures: 。 5. The polymerizable liquid crystal mixture according to claim 1, characterized in that, The polymeric liquid crystal mixture comprises, by weight, 5 to 80 parts of the polymeric liquid crystal compound A and 10 to 90 parts of the polymeric liquid crystal compound B.

6. A polymerizable composition, characterized in that, The polymeric liquid crystal mixture comprising any one of claims 1 to 5.

7. The polymerizable composition according to claim 6, characterized in that, The polymerizable composition further comprises a polymerizable liquid crystal compound N; The polymerizable liquid crystal compound N is selected from the following structures: 。 8. The polymerizable composition according to claim 7, characterized in that, The polymeric liquid crystal composition comprises, by weight, 40 to 99.9 parts of the polymeric liquid crystal mixture and 0.1 to 60 parts of the polymeric liquid crystal compound N.

9. A phase retardation film, characterized in that, The phase difference film comprises a polymer product polymerized from the polymeric composition of any one of claims 6 to 8.

10. The phase retardation film according to claim 9, characterized in that, The phase difference R450 of the phase retardation film at a wavelength of 450 nm and the phase difference R550 at a wavelength of 550 nm satisfy the following: R450 / R550 < 1.0.

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