Cholesterol liquid crystal composition

Abstract

Provided is a cholesteric liquid crystal composition capable of producing a cholesteric liquid crystal element having high contrast and short response time, the cholesteric liquid crystal composition containing: a host liquid crystal composition containing, as a first component, at least one compound selected from the group consisting of compounds represented by formula (1); and at least one optically active compound selected from the group consisting of compounds represented by formula (CH1) or formula (CH2) as a first additive and at least one polymerizable compound selected from the group consisting of compounds represented by formula (M1) as a second additive, the content of the second additive being less than 2.0 mass% based on the mass of the host liquid crystal composition.

Description

Technical Field

[0001] This invention relates to a cholesterol-type liquid crystal composition. Background Technology

[0002] Liquid crystal elements containing a liquid crystal composition exhibiting a "cholesterol phase" are known. The cholesterol phase is a liquid crystal phase in which the orientation of the molecules rotates in a manner resembling a helix. The helical axis is perpendicular to the direction of the orientation order. Furthermore, the helical period is referred to as the "pitch". Liquid crystal compositions exhibiting a cholesterol phase display selective reflection of circularly polarized light, with the rotation direction of the light vector corresponding to the left-right characteristic (handedness) of the cholesterol helix. The reflected wavelength λ can be calculated using equation (A) based on the pitch P of the cholesterol helix and the average birefringence n of the cholesterol-type liquid crystal.

[0003] λ=n×P (A)

[0004] Furthermore, the spacing depends, for example, on the type of optically active compound in the liquid crystal composition or its concentration. For instance, Patent Document 1 discloses a cholesterol-type liquid crystal composition containing an optically active compound having an octahydrobinaphthyl skeleton.

[0005] The most common cholesterol-type liquid crystal elements are SSCT (Surface Stability Cholesteric Texture) and PSCT (Polymer Stability Cholesteric Texture) elements. Cholesteric liquid crystal compositions forming SSCT and PSCT elements, for example, exhibit a planar structure reflecting light of a specific wavelength in the initial stage without applied voltage, and can be switched to a focal conic light-scattering structure, or vice versa, by applying an alternating current pulse.

[0006] These liquid crystal elements remain in their bistable state after the electric field is switched off, and only revert to their initial state when the electric field is applied again. If a higher voltage pulse is applied, the cholesterol-type liquid crystal composition transitions to a homeotropic, transparent state, and from this state, relaxes to a planar state when the voltage is rapidly switched off, and to a focal cone state when the voltage is switched slowly. The minimum driving voltage required to return from the planar state (reflection) to the homeotropic phase (transmission) is called the Vreset voltage. The lower the driving voltage, the less power is consumed.

[0007] Cholesterol-type liquid crystal elements generally do not require backlighting. In planar alignment, the cholesterol-type liquid crystal composition in the pixel exhibits selective reflection of light of a specific wavelength according to formula (A), resulting in the pixel being visible against a black background in the corresponding reflected color. If the shift is to a scattering state caused by the focal cone structure or a vertically transparent state, the reflected color disappears. Cholesterol-type liquid crystal elements become color displays in a planar state; therefore, to achieve good contrast, it is particularly important to stably maintain the planar structure when no voltage is applied. Furthermore, a short response time is required for displaying dynamic images.

[0008] [Existing Technical Documents]

[0009] [Patent Literature]

[0010] [Patent Document 1] Japanese Patent Application Publication No. 2021-152137 Summary of the Invention

[0011] [The problem the invention aims to solve]

[0012] The objective of this invention is to provide a liquid crystal composition capable of manufacturing cholesterol-type liquid crystal elements with higher contrast and shorter response time.

[0013] [Technical means to solve the problem]

[0014] The inventors and others conducted intensive research and discovered that the following liquid crystal composition, namely, a liquid crystal composition containing an optically active compound, a liquid crystal compound having a cyano group, and a polymerizable compound having a specified amount of mesocrystalline site, solves the aforementioned problem, thereby completing the present invention.

[0015] The present invention includes the following items, etc.

[0016] Item 1. A cholesterol-type liquid crystal composition comprising: a host liquid crystal composition, said host liquid crystal composition comprising, as a first component, at least one compound selected from compounds represented by formula (1); and, as a first additive, at least one optically active compound selected from compounds represented by formulas (Ch1) and (Ch2); and as a second additive, at least one polymerizable compound selected from compounds represented by formula (M1).

[0017] Based on the mass of the main liquid crystal composition, the content of the second additive was less than 2.0% by mass.

[0018] [Chemistry 1]

[0019]

[0020] In equation (1), R 11It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; cyclic A 1 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 11 It is a single bond, a carbonyl group, or a difluoromethylene group; X 11 and X 12 It is hydrogen or fluorine; n1 is 1 or 2;

[0021] In equations (Ch1) and (Ch2), R 1 R 2 and R 3 It is hydrogen, halogen, cyano, -SF5, or an alkyl group having 1 to 10 carbon atoms, wherein at least one -CH2- may be substituted with -O-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and wherein at least one hydrogen atom may be substituted with fluorine or chlorine; ring A, ring B, ring E, and ring F are 5,6,7,8-tetrahydronaphthyl-1,2-diyl or naphthyl-1,2-diyl; ring C, ring D, and ring G are 1,4-cyclohexene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidin-2,5-diyl, pyridine-2,5-diyl, or 1,4-bicyclo-(2,2,2)-octylene, wherein at least one hydrogen atom may be substituted with fluorine or chlorine; Z 1 Z 2 Z 3 Z 4 and Z 5 It is a single bond or an alkylene group having 1 to 20 carbon atoms, wherein at least one -CH2- group may be substituted with -O-, -CO-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and wherein at least one hydrogen atom may be substituted with fluorine or chlorine; a, b, and c are 2, 3, or 4;

[0022] In equation (M1), R a and R b The polymerizable group, hydrogen, halogen, -C≡N, -N=C=O, or -N=C=S, R, represented by any of formulas (P-1) to (P-6) a and R b At least one of them is the polymeric group,

[0023] [Chemistry 2]

[0024]

[0025] In equations (P-1) to (P-6), M 1To M 3 It is hydrogen, fluorine, an alkyl group having 1 to 5 carbon atoms, or at least one hydrogen-substituted fluorine alkyl group having 1 to 5 carbon atoms, in the M 1 To M 3 In this case, at least one -CH2- of the alkyl group may be substituted via -O-; A M1 and A M2 A divalent group formed by removing hydrogen from two aromatic rings, wherein at least one hydrogen may be substituted by a halogen, an alkyl group having 1 to 5 carbon atoms, a alkyl halide having 1 to 5 carbon atoms, at least one -CH2- substituted with -O- or -COO- of an alkyl group having 1 to 5 carbon atoms, a polymerizable group represented by any of formulas (P-1) to (P-6), an alkyl group having 1 to 5 carbon atoms substituted by a polymerizable group represented by any of formulas (P-1) to (P-6), or an alkyl halide having 1 to 5 carbon atoms substituted by a polymerizable group represented by any of formulas (P-1) to (P-6); Y M1 and Y M2 It is a single bond or an alkylene group having 1 to 12 carbon atoms, wherein at least one -CH2- may be substituted with -O- or -S-, and at least one -CH2-CH2- may be substituted with -CH=CH-, -C≡C-, -COO-, or -OCO-; Y M1 and Y M2 At least one of them is a single bond, or at least one -CH2- alkylene group having 1 to 4 carbon atoms that can be substituted via -O-; Z M It is a single bond, -(CH2) m2 -、-O(CH2) m2 -、-(CH2) m2 O-, -O(CH2) m2 O-, -CH=CH-, -C≡C-, -COO-, -OCO-, -(CF2)2-, -(CH2)2-COO-, -OCO-(CH2)2-, -CH=CH-COO-, -OCO-CH=CH-, -C≡C-COO-, -OCO-C≡C-, -CH=CH-(CH2)2-, -(CH2)2-CH=CH-, -CF=CF-, -C≡C-CH=CH-, -CH=CH-C≡C-, -OCF2-(CH2)2-, -(CH2)2-CF2O-, -OCF2-, or -CF2O- (in the above formulas, m2 is 1 or 2); m1 is an integer from 1 to 5.

[0026] Item 2. The cholesterol-type liquid crystal composition according to Item 1, wherein the polymerizable group represented by any one of formulas (P-1) to (P-6) included in formula (M1) is two or three, R a and R bAll of them are polymeric groups represented by any one of formulas (P-1) to (P-6).

[0027] Item 3. The cholesterol-type liquid crystal composition according to Item 1 or Item 2, wherein the total content of polymeric compounds is less than 2.0% by mass based on the mass of the host liquid crystal composition.

[0028] Item 4. The cholesterol-type liquid crystal composition according to any one of items 1 to 3, wherein Y M1 and Y M2 It is a single bond or an alkylene group having 1 to 8 carbon atoms, wherein at least one -CH2- may be substituted with -O- or -S-, and at least one -CH2-CH2- may be substituted with -CH=CH-, -C≡C-, -COO-, or -OCO-, Y M1 and Y M2 At least one of them is a single bond, or at least one -CH2- alkylene group having 1 to 4 carbon atoms that can be substituted by -O-.

[0029] Item 5. The cholesterol-type liquid crystal composition according to any one of Items 1 to 4, comprising as a second additive at least one polymeric compound selected from compounds represented by formulas (M1-1) to (M1-5).

[0030] [Chemistry 3]

[0031]

[0032] In equations (M1-1) to (M1-5),

[0033] R a R b Y, Z M respectively with R in equation (M1) a R b Y, Z M They have the same meaning.

[0034] X M1 The following are possible meanings: halogen, alkyl group having 1 to 5 carbon atoms, alkyl halide having 1 to 5 carbon atoms, at least one alkyl group having 1 to 5 carbon atoms substituted with -CH2- or -O- or -COO-, a polymerizable group represented by any of formulas (P-1) to (P-6), at least one alkyl group having 1 to 5 carbon atoms substituted with a polymerizable group represented by any of formulas (P-1) to (P-6), or at least one alkyl halide having 1 to 5 carbon atoms substituted with a polymerizable group represented by any of formulas (P-1) to (P-6), X M2 It is hydrogen or methyl, f is 0, 1, 2, 3, or 4, g is 0, 1, 2, or 3, and h is 0, 1, or 2.

[0035] Item 6. The cholesterol-type liquid crystal composition according to any one of items 1 to 5, wherein the content of the polymerization initiator is less than 0.1% by mass based on the mass of the host liquid crystal composition.

[0036] Item 7. The cholesterol-type liquid crystal composition according to any one of Items 1 to 6, comprising, as a first additive, at least one optically active compound selected from the compounds represented by formulas (Ch1-1) to (Ch1-6) and (Ch2-1) to (Ch2-3).

[0037] [Chemistry 4]

[0038]

[0039] [Chemistry 5]

[0040]

[0041] In equations (Ch1-1) to (Ch1-6) and equations (Ch2-1) to (Ch2-3), R 1 R 2 and R 3 It is hydrogen, halogen, cyano, -SF5, or an alkyl group having 1 to 10 carbon atoms, wherein at least one -CH2- group may be substituted with -O-, -COO-, -OCO-, -CH=CH-, or -C≡C-, wherein at least one hydrogen atom may be substituted with fluorine or chlorine; ring A, ring B, ring E, and ring F are 5,6,7,8-tetrahydronaphthalene-1,2-diyl or naphthalene-1,2-diyl.

[0042] Item 8. The cholesterol-type liquid crystal composition according to any one of items 1 to 7, wherein the content of the first additive is in the range of 0.1% by mass to 10% by mass based on the mass of the host liquid crystal composition.

[0043] Item 9. The cholesterol-type liquid crystal composition according to any one of Items 1 to 8, comprising as a first component at least one compound selected from the compounds represented by formulas (1-1) to (1-9).

[0044] [Chemistry 6]

[0045]

[0046] In equations (1-1) to (1-9), R 11 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; X 11 and X 12 It is either hydrogen or fluorine.

[0047] Item 10. The cholesterol-type liquid crystal composition according to any one of items 1 to 9, wherein the content of the first component is in the range of 5% by mass to 30% by mass based on the mass of the host liquid crystal composition.

[0048] Item 11. The cholesterol-type liquid crystal composition according to any one of items 1 to 10, wherein the main liquid crystal composition further comprises, as a second component, at least one compound selected from the compounds represented by formula (2).

[0049] [Chemistry 7]

[0050]

[0051] In equation (2), R 21 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; cyclic C 2 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 21 For single bonds, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy; X 21 and X 22 It is hydrogen or fluorine; Y 21 It is fluorine, chlorine, an alkyl group having 1 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine; n2 is 1, 2, 3, or 4.

[0052] Item 12. The cholesterol-type liquid crystal composition according to Item 11, comprising as a second component at least one compound selected from the compounds represented by formulas (2-1) to (2-38).

[0053] [Chemistry 8]

[0054]

[0055] [Chemistry 9]

[0056]

[0057] [Chemistry 10]

[0058]

[0059] [Chemistry 11]

[0060]

[0061] [Chemistry 12]

[0062]

[0063] In equations (2-1) to (2-38), R 21 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms.

[0064] Item 13. The cholesterol-type liquid crystal composition according to Item 11 or Item 12, wherein the content of the second component is in the range of 5% by mass to 50% by mass based on the mass of the main liquid crystal composition.

[0065] Item 14. The cholesterol-type liquid crystal composition according to any one of items 1 to 13, wherein the main liquid crystal composition further comprises, as a third component, at least one compound selected from the compounds represented by formula (3).

[0066] [Chemistry 13]

[0067]

[0068] In equation (3), R 31 and R 32 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine; cyclic C 3 and ring D 3 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z 31 n is a single bond, ethylidene, vinylidene, ethynylidene, methyleneoxy, or carbonyloxy; n3 is 1, 2, or 3.

[0069] Item 15. The cholesterol-type liquid crystal composition according to Item 14 further comprises, as a third component, at least one compound selected from the compounds represented by formulas (3-1) to (3-20).

[0070] [Chemistry 14]

[0071]

[0072] [Chemistry 15]

[0073]

[0074] In equations (3-1) to (3-20), R 31 and R 32 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine.

[0075] Item 16. The cholesterol-type liquid crystal composition according to Item 14 or Item 15, wherein the content of the third component is in the range of 10% by mass to 90% by mass based on the mass of the main liquid crystal composition.

[0076] Item 17. The cholesterol-type liquid crystal composition according to any one of Items 1 to 16, wherein the optical anisotropy of the main liquid crystal composition at a wavelength of 589 nm (measured at 25 °C) is in the range of 0.10 to 0.40, and the dielectric anisotropy of the main liquid crystal composition at a frequency of 1 kHz (measured at 25 °C) is in the range of 10 to 100.

[0077] Item 18. The cholesterol-type liquid crystal composition according to any one of items 1 to 17, wherein the reflectance wavelength is selected in the range of 350 nm to 800 nm.

[0078] [The effects of the invention]

[0079] This invention provides a cholesterol-type liquid crystal composition capable of producing higher contrast and shorter response time. Detailed Implementation

[0080] The terminology used in this specification is as follows. Sometimes, the terms "liquid crystal composition" and "liquid crystal element" are abbreviated as "composition" and "element," respectively. "Liquid crystal element" is a general term for liquid crystal display panels, liquid crystal display modules, and liquid crystal devices that use liquid crystal compositions. "Liquid crystal compound" is a general term for compounds having liquid crystal phases such as nematic, cholesterol, or lamina phases, as well as compounds that, although not having a liquid crystal phase, are mixed in the composition for the purpose of adjusting the temperature range, viscosity, dielectric anisotropy, and other properties of the liquid crystal phase. The compound has, for example, a six-membered ring such as 1,4-cyclohexylene or 1,4-phenylene, and its molecular structure is rod-like.

[0081] The description of the compounds in this specification is illustrated by taking the following compound (1z) as an example.

[0082] [Chemistry 16]

[0083]

[0084] In formula (1z), the notations for α and β enclosed by hexagons correspond to ring α and ring β, respectively, representing six-membered rings, condensed rings, and the like. When the subscript 'x' is 2, there are two rings α. The two groups represented by the two rings α can be the same or different. This rule applies to any two rings α when the subscript 'x' is greater than 2. This rule also applies to other notations such as bonding group Z. A diagonal line cut across one side of ring β indicates that any hydrogen on ring β can be substituted by a substituent (-Sp-P). The subscript 'y' indicates the number of substituents substituted. When the subscript 'y' is 0, this substitution does not exist. When the subscript 'y' is 2 or greater, there are multiple substituents (-Sp-P) on ring β. In this case, the rule of "can be the same or different" also applies. Furthermore, this rule also applies when the notation Ra is used in multiple compounds.

[0085] In formula (1z), expressions such as "Ra and Rb are alkyl, alkoxy, or alkenyl" mean that Ra and Rb are independently selected from the group consisting of alkyl, alkoxy, and alkenyl. Here, the group represented by Ra may be the same as or different from the group represented by Rb.

[0086] Sometimes, at least one compound selected from the compounds represented by formula (1z) is simply referred to as "compound (1z)". "Compound (1z)" means one compound, a mixture of two compounds, or a mixture of three or more compounds represented by formula (1z). The same applies to compounds represented by other formulas. The statement "at least one compound selected from the compounds represented by formula (1z) and formula (2z)" means at least one compound selected from the group consisting of compounds (1z) and (2z). Similarly, the statements "at least one compound selected from the compounds represented by formulas (1z) to (3z)" mean at least one compound selected from the group consisting of compounds (1z), compounds (2z), and compounds (3z).

[0087] The statement "at least one 'A'" means that the number of 'A's is arbitrary. The statement "at least one 'A' can be substituted by 'B'" means that when there is only one 'A', the position of 'A' is arbitrary; when there are two or more 'A's, their positions can also be chosen without restriction. Sometimes the statement "at least one -CH2- can be substituted by -O-" is used. In this case, -CH2-CH2-CH2- can be converted to -O-CH2-O- by substituting a non-adjacent -CH2- with -O-. However, there is no case of adjacent -CH2- being substituted with -O-. The reason is that -OO-CH2- (peroxide) is generated in this substitution.

[0088] The alkyl groups in liquid crystal compounds are either straight-chain or branched, and do not contain cyclic alkyl groups. Straight-chain alkyl groups are preferred over branched alkyl groups. The same applies to terminal groups such as alkoxy and alkenyl groups. Regarding the stereoconfiguration associated with 1,4-cyclohexene, the trans configuration is preferred over the cis configuration to increase the upper temperature limit. Because 2-fluoro-1,4-phenylene is left-right asymmetric, both left-facing (L) and right-facing (R) configurations exist.

[0089] [Chemistry 17]

[0090]

[0091] The same applies to divalent groups such as tetrahydropyran-2,5-diyl. The same also applies to bonding groups such as carbonyloxy groups (-COO- or -OCO-).

[0092] Liquid crystal compositions are prepared by mixing various liquid crystal compounds. Additives such as optically active compounds, antioxidants, UV absorbers, pigments, defoamers, polymerizable compounds, polymerization initiators, and polymerization inhibitors are added to the liquid crystal composition as needed. For these additives, the liquid crystal composition is sometimes referred to as the "main liquid crystal composition," or combined with the type of liquid crystal phase, for example, as a "main nematic liquid crystal composition." Additionally, each liquid crystal compound in the "main liquid crystal composition" is sometimes referred to as a "component compound." The proportion (content) of the liquid crystal compounds is expressed as a mass percentage (mass %) based on the mass of the main liquid crystal composition. The proportion (amount) of the additives is expressed as a mass percentage relative to the mass of the main liquid crystal composition. Furthermore, depending on the additive, parts per million (ppm) are sometimes used.

[0093] The proportion of liquid crystal compounds, additives, or other substances contained in the composition can be determined by analyzing the mixture of liquid crystal compounds using gas chromatography with a flame ionization detector (FID). The area ratio of the peaks in the gas chromatogram corresponds to the proportion of the liquid crystal compounds.

[0094] In this specification, a liquid crystal composition that displays a "cholesterol phase" by adding an optically active compound to a host liquid crystal composition that displays a nematic phase is referred to as a "cholesterol-type liquid crystal" or "cholesterol-type liquid crystal composition".

[0095] Sometimes the "upper limit temperature of the nematic or cholesterol phase" is simply referred to as the "upper limit temperature." Sometimes the "lower limit temperature of the nematic or cholesterol phase" is simply referred to as the "lower limit temperature." "High resistivity" means that the composition exhibits high resistivity not only at room temperature but also near the upper limit temperature of the cholesterol phase in the initial stage, and continues to exhibit high resistivity not only at room temperature but also near the upper limit temperature of the cholesterol phase after prolonged use. "High voltage retention rate" means that the element exhibits high voltage retention rate not only at room temperature but also near the upper limit temperature of the cholesterol phase in the initial stage, and continues to exhibit high voltage retention rate not only at room temperature but also near the upper limit temperature of the cholesterol phase after prolonged use.

[0096] The cholesterol-type liquid crystal composition of the present invention has suitable properties. By improving the properties of the composition, a liquid crystal element with good properties can be obtained.

[0097] The ratio of the reflectance of the planar state to the focal conical state of the cholesterol-type liquid crystal composition is related to the contrast ratio of the cholesterol-type liquid crystal element. As shown in the examples, this reflectance ratio can be obtained by dividing the reflectance when the voltage is turned off after a high voltage is applied by the reflectance when the voltage is turned off after a low voltage is applied. Preferably, this ratio is large.

[0098] The viscosity of the composition is related to the response time of the element. For the element to display dynamic images, a short response time is preferred. Ideally, a response time of less than 1 millisecond is desired. Therefore, a low viscosity of the composition is preferred. The viscosity at 25°C is preferably 120 mPa·s or less, more preferably 80 mPa·s or less. Even more preferred is a low viscosity at lower temperatures.

[0099] Regarding the helical pitch length of the composition, in order not to impair the characteristics of the main nematic liquid crystal composition, it is preferable to adjust the reflected wavelength to the visible region using the least amount of optically active compound added. Furthermore, in order not to degrade display quality due to changes in ambient temperature, it is preferable that the temperature dependence of the helical pitch length is almost zero or minimal.

[0100] The temperature range of the cholesterol phase is related to the usable temperature range of the element. The preferred upper limit temperature of the cholesterol phase is above about 70°C, and the preferred lower limit temperature is below about -10°C. A high resistivity of the composition contributes to a high voltage retention rate of the element. Therefore, a composition exhibiting a high resistivity not only at room temperature but also at temperatures close to the upper limit temperature of the cholesterol phase is preferred. A composition exhibiting a high resistivity not only at room temperature but also at temperatures close to the upper limit temperature of the cholesterol phase is preferred even after prolonged use. The resistivity of the liquid crystal composition at room temperature is preferably 1 × 10⁻⁶. 10 Ω·cm or higher, more preferably 1×1012 Ω·cm or higher, and more preferably 1×10 14 Ω·cm or higher.

[0101] The optical anisotropy of the composition is associated with a bright display. To achieve a bright display, a liquid crystal composition with relatively large optical anisotropy is required. The optical anisotropy at a wavelength of 589 nm (measured at 25°C), based on the value of the main liquid crystal composition, is preferably in the range of 0.10 to 0.40, more preferably in the range of 0.12 to 0.35, and even more preferably in the range of 0.15 to 0.30. High dielectric anisotropy of the composition contributes to a low driving voltage for the device; therefore, a relatively large dielectric anisotropy is preferred. The dielectric anisotropy at a frequency of 1 kHz (measured at 25°C), based on the value of the main liquid crystal composition, is preferably in the range of 10 to 100, more preferably in the range of 10 to 60, even more preferably in the range of 15 to 55, and particularly preferably in the range of 20 to 50.

[0102] The cholesterol-type liquid crystal composition of the present invention will be described in the following order: First, the structure of the composition will be described. Second, the main characteristics of the additives and component compounds in the main liquid crystal composition, and the main effects of said compounds on the cholesterol-type liquid crystal composition or element, will be described. Third, the combination and proportion of the additives and component compounds in the composition will be described. Fourth, the preferred forms of the additives and component compounds will be described. Fifth, preferred additives and component compounds will be shown. Sixth, additives that can be added to the composition will be described. Seventh, the synthesis method of the additives and component compounds will be described. Finally, the use of the composition will be described.

[0103] First, the structure of the cholesterol-type liquid crystal composition of the present invention will be described.

[0104] The cholesterol-type liquid crystal composition of the present invention comprises: a host liquid crystal composition, said host liquid crystal composition comprising, as a first component, at least one compound selected from compounds represented by formula (1); as a first additive, at least one optically active compound selected from compounds represented by formulas (Ch1) and (Ch2); and as a second additive, at least one polymerizable compound selected from compounds represented by formula (M1). In the cholesterol-type liquid crystal composition of the present invention, the content of the second additive is less than 2.0% by mass based on the mass of the host liquid crystal composition.

[0105] The compositions of the present invention may also contain other liquid crystal compounds, other additives, etc. "Other liquid crystal compounds" are liquid crystal compounds different from compound (1), and are second components, third components, etc., described later. "Other additives" are additives different from compound (Ch1), compound (Ch2), or compound (M1), which are mixed into the composition for the purpose of further adjusting properties. Other additives include antioxidants, ultraviolet absorbers, pigments, defoamers, polymerizable compounds, polymerization initiators, polymerization inhibitors, polar compounds, etc.

[0106] Second, the main characteristics of the additives and the constituent compounds in the main liquid crystal composition, as well as the main effects of the compounds on the cholesterol-type liquid crystal composition or element, are explained.

[0107] When compound (Ch1) or compound (Ch2) (the first additive), which is an optically active compound, is added to the host nematic liquid crystal composition, a cholesterol phase is revealed. Therefore, the structures of compounds (Ch1) and (Ch2) are not racemic. Furthermore, compounds (Ch1) or (Ch2) can be manufactured using the method described in International Publication No. 2014 / 097952. The cholesterol-type liquid crystal composition of the present invention, by using compound (Ch1) or compound (Ch2) as an optically active compound, utilizes a small amount of the added optically active compound to achieve a reflective wavelength in the visible region. Additionally, the temperature dependence of the helical pitch length is low.

[0108] The compound represented by formula (M1) contributes to improved contrast when added in a specified amount to the composition.

[0109] The cholesterol-type liquid crystal composition of the present invention has low viscosity, short response time of the element, and can reduce driving voltage by including compound (1) as the first component in the main liquid crystal composition.

[0110] Based on the effects of this invention, the main characteristics of the first component and other component compounds in the main liquid crystal composition are summarized in Table 1. In Table 1, L indicates large or high, M indicates moderate, and S indicates small or low. The symbols L, M, and S are classifications based on qualitative comparisons between component compounds, and 0 (zero) indicates extremely small.

[0111] [Table 1]

[0112] Table 1. Properties of the compounds

[0113] compound Compound (1) Compound (2) Compound (3) Upper limit temperature S~L S~L S~L Viscosity S~M M~L S Optical anisotropy S~M M~L S~L Dielectric anisotropy L M~L 0 resistivity S L L

[0114] The main effects of the constituent compounds on the properties of the composition are as follows. Compound (1), as the first component, reduces viscosity and improves dielectric anisotropy. Compound (2), as the second component, improves dielectric anisotropy. Compound (3), as the third component, reduces viscosity, improves optical anisotropy, and increases the upper limit temperature or decreases the lower limit temperature.

[0115] Third, the combination and proportion of additives and component compounds in the composition are described. The composition contains at least a combination of compound (1) + compound (Ch1) or compound (Ch2) + compound (M1). Preferably, it is compound (1) + compound (Ch1) or compound (Ch2) + compound (M1) + compound (2), compound (1) + compound (Ch1) or compound (Ch2) + compound (M1) + compound (3), or compound (1) + compound (Ch1) or compound (Ch2) + compound (M1) + compound (2) + compound (3). More preferably, it is compound (1) + compound (Ch1) or compound (Ch2) + compound (M1) + compound (2) + compound (3).

[0116] Based on the mass of the host liquid crystal composition, in order to obtain a stable torsional state in the cholesterol-type liquid crystal composition, the preferred addition ratio of compound (Ch1) or compound (Ch2) is 0.1% by mass or more. To avoid impairing the properties of the host nematic liquid crystal composition, the preferred addition ratio of compound (Ch1) or compound (Ch2) is 10% by mass or less. More preferably, the addition ratio is in the range of 0.5% by mass to 7% by mass. Particularly preferred is the addition ratio in the range of 1% by mass to 5% by mass.

[0117] The proportion of compound (M1) in the composition is less than 2.0% by mass, based on the mass of the host liquid crystal composition. The inventors have found that cholesterol-type liquid crystal compositions containing compound (M1) as a polymerizable compound having a specific structure at less than 2.0% by mass provide high contrast. The content of compound (M1) is only required to be 0.1% by mass or more, preferably 0.2% by mass or more. Cholesterol-type liquid crystal compositions provide particularly high contrast, especially when the content of compound (M1) is from 0.3% to 1.5% by mass. When the cholesterol-type liquid crystal composition contains polymerizable compounds other than compound (M1), especially when it contains polymerizable compounds having polymerizable groups represented by any of formulas (P-1) to (P-6), it is preferable that the total content of compound (M1) and polymerizable compounds other than compound (M1) is less than 2.0% by mass, based on the mass of the host liquid crystal composition. At this time, based on the mass of the main liquid crystal composition, it contains at least 0.2% by mass, preferably 0.3% by mass or more of compound (M1), and based on the mass of the total content of polymerizable compounds, the content of compound (M1) is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 70% by mass or more.

[0118] Based on the mass of the main liquid crystal composition, in order to reduce viscosity and increase dielectric anisotropy, the preferred proportion of compound (1) as the first component is 5% by mass or more. Furthermore, it is preferably 30% by mass or less. More preferably, the proportion is in the range of 10% by mass to 25% by mass. Particularly preferred is the proportion in the range of 10% by mass to 20% by mass.

[0119] When the main liquid crystal composition contains a second component, based on the mass of the main liquid crystal composition, in order to increase dielectric anisotropy, the preferred proportion of compound (2) as the second component is 5% by mass or more, and in order not to increase viscosity and not to raise the lower limit temperature, the preferred proportion of compound (2) as the second component is 50% by mass or less.

[0120] When the main liquid crystal composition contains a third component, based on the mass of the main liquid crystal composition, the preferred proportion of compound (3) as the third component is 10% by mass or more in order to reduce viscosity or to adjust optical anisotropy, and the preferred proportion of compound (3) as the third component is 90% by mass or less in order not to reduce dielectric anisotropy. More preferably, the proportion is in the range of 30% by mass to 85% by mass. Particularly preferred is the proportion in the range of 45% by mass to 80% by mass.

[0121] Fourth, the preferred forms of additives and component compounds are described.

[0122] Preferred forms of the compounds represented by formulas (Ch1) and (Ch2) as first additives will be described. 1 R 2 and R 3 It is hydrogen, halogen, cyano, -SF5, or an alkyl group having 1 to 10 carbon atoms, wherein at least one -CH2- group may be substituted with -O-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and wherein at least one hydrogen atom may be substituted with fluorine or chlorine. Preferred R 1 R 2 、or R 3 It is an alkyl group having 1 to 10 carbon atoms. Rings A, B, E, and F are 5,6,7,8-tetrahydronaphthalene-1,2-diyl or naphthalene-1,2-diyl. Preferably, ring A or ring B is 5,6,7,8-tetrahydronaphthalene-1,2-diyl, and preferably ring E or ring F is naphthalene-1,2-diyl. Rings C, D, and G are 1,4-cyclohexene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidin-2,5-diyl, pyridine-2,5-diyl, or 1,4-bicyclo-(2,2,2)-octylene, wherein at least one hydrogen atom may be substituted with fluorine or chlorine. Preferably, ring C, ring D, or ring G is 1,4-cyclohexene or 1,4-phenylene. 1 Z 2 Z 3 Z 4 and Z 5 It is a single bond or an alkylene group having 1 to 20 carbon atoms, wherein at least one -CH2- group may be substituted with -O-, -CO-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and in these groups, at least one hydrogen atom may be substituted with fluorine or chlorine. Preferred Z 1 Z 2 Z 3 Z 4 、or Z 5 It is a single bond or -OCO-. a, b, and c are 2, 3, or 4. Preferably, a, b, or c are 2 or 3.

[0123] The preferred form of the compound represented by formula (M1) as a second additive will be described. a and R b Polymerizable groups represented by any of formulas (P-1) to (P-6) (hereinafter referred to as "polymerizable groups represented by formulas (P-1) to (P-6)"), hydrogen, halogen, -C≡N, -N=C=O, or -N=C=S, R a and R b At least one of them is the polymeric group.

[0124] [Chemistry 18]

[0125]

[0126] In equations (P-1) to (P-6), M 1 To M 3 It is hydrogen, fluorine, an alkyl group having 1 to 5 carbon atoms, or at least one hydrogen-substituted fluorine alkyl group having 1 to 5 carbon atoms, in the M 1 To M 3 In this configuration, at least one -CH2- group of the alkyl group may be substituted with -O-. Preferred R a or R b The polymerizable group is represented by formula (P-1). Preferred M 1 M 2 、 or M 3 It can be hydrogen, fluorine, or methyl.

[0127] In equation (M1), A M1 and A M2 A divalent group formed by removing hydrogen from two aromatic rings. Examples of divalent groups formed by removing hydrogen from two aromatic rings include 1,4-phenylene, naphthalene-2,6-diyl, tetrahydronaphthalene-2,6-diyl, phenanthrene-2,7-diyl, or fluorene-2,7-diyl, etc., wherein at least one -CH2- in the ring may be substituted with -O-, and at least one -CH= in the ring may be substituted with -N=. Additionally, in these rings, at least one hydrogen may be substituted with a halogen, an alkyl group having 1 to 5 carbon atoms, an alkyl group having 1 to 5 carbon atoms substituted with a halogen (a alkyl halide having 1 to 5 carbon atoms), an alkyl group having 1 to 5 carbon atoms substituted with a -CH2- group substituted with a -O- or -COO- group, a polymerizable group represented by formulas (P-1) to (P-6), an alkyl group having 1 to 5 carbon atoms substituted with a polymerizable group represented by any of formulas (P-1) to (P-6), or an alkyl halide having 1 to 5 carbon atoms substituted with a polymerizable group represented by any of formulas (P-1) to (P-6). Preferred A M1 Or A M2 It is 1,4-phenylene or fluorene-2,7-diyl, in which at least one hydrogen may be substituted by fluorine, an alkyl group having 1 to 5 carbon atoms, or a polymerizable group represented by formula (P-1).

[0128] In equation (M1), Y M1 and Y M2 It is a single bond or an alkylene group having 1 to 12 carbon atoms, wherein at least one -CH2- may be substituted with -O- or -S-, and at least one -CH2-CH2- may be substituted with -CH=CH-, -C≡C-, -COO-, or -OCO-, Y M1 and Y M2At least one of them is a single bond, or at least one -CH2-alkylene group with 1 to 4 carbon atoms that can be substituted with -O-. Thus, the polymerizable group is directly bonded to the ring structure, or the chain length of the polymerizable group and the bonded group of the ring structure is relatively short, such as at least one -CH2-alkylene group with 1 to 4 carbon atoms that can be substituted with -O-, thereby it is believed that compound (M1) improves the stability of the cholesterol-type composition in the planar structure state. Furthermore, Y M1 and Y M2 At least one of them is preferably a single bond, or at least one -CH2-substituted alkylene group with 4 carbon atoms.

[0129] In equation (M1), Z M It is a single bond, -(CH2) m2 -、-O(CH2) m2 -、-(CH2) m2 O-, -O(CH2) m2 O-, -CH=CH-, -C≡C-, -COO-, -OCO-, -(CF2)2-, -(CH2)2-COO-, -OCO-(CH2)2-, -CH=CH-COO-, -OCO-CH=CH-, -C≡C-COO-, -OCO-C≡C-, -CH=CH-(CH2)2-, -(CH2)2-CH=CH-, -CF=CF-, -C≡C-CH=CH-, -CH=CH-C≡C-, -OCF2-(CH2)2-, -(CH2)2-CF2O-, -OCF2-, or -CF2O-, where m2 is 1 or 2. Preferred Z M It is a single bond, -C≡C-, -COO-, or -OCO-. m1 is an integer from 1 to 5, preferably an integer from 1 to 3, more preferably 1 or 2, and even more preferably 2. In particular, in compound (M1), it is preferred when A M1 and A M2 When both are 1,4-phenylene, m1 is 2.

[0130] In equations (M1-1) to (M1-5), R a R b Y, Z M respectively with R in equation (M1) a R b Y, Z M They have the same meaning.

[0131] X M1It is a halogen, an alkyl group having 1 to 5 carbon atoms, a alkyl halide having 1 to 5 carbon atoms, at least one alkyl group having 1 to 5 carbon atoms substituted with -CH2- or -O- or -COO-, a polymerizable group represented by any of formulas (P-1) to (P-6), an alkyl group having 1 to 5 carbon atoms substituted with at least one hydrogen atom substituted with a polymerizable group represented by any of formulas (P-1) to (P-6), or an alkyl halide having 1 to 5 carbon atoms substituted with at least one hydrogen atom substituted with a polymerizable group represented by any of formulas (P-1) to (P-6). Preferred X M1 It is a polymerizable group represented by fluorine, an alkyl group having 1 to 5 carbon atoms, or any of the formulas (P-1) to (P-6). X M2 It can be hydrogen or methyl. f is 0, 1, 2, 3, or 4, g is 0, 1, 2, or 3, and h is 0, 1, or 2.

[0132] Compound (M1) is a polymerizable compound. The polymerizable groups represented by formulas (P-1) to (P-6) included in formula (M1) are preferably two or three, more preferably two. R is preferred. a and R b All of them are polymerizable groups represented by formulas (P-1) to (P-6). Preferably, the polymerizable groups included in formula (M1) are polymerizable groups represented by formula (P-1).

[0133] Preferred forms of the component compounds in the main liquid crystal composition, namely the compounds represented by formula (1), formula (2), and formula (3), will be described. 11 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms. For improved stability, R is preferred. 11 The alkyl group having 1 to 12 carbon atoms is preferred, and R is preferred for reducing viscosity. 11 It is an alkenyl group having 2 to 12 carbon atoms. R 21 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms. For improved stability, R is preferred. 21 It is an alkyl group having 1 to 12 carbon atoms. R 31 and R 32 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine. For improved stability, R is preferred. 31 or R 32 The alkyl group having 1 to 12 carbon atoms is preferred, and R is preferred for reducing viscosity. 31 or R 32 It is an alkenyl group with 2 to 12 carbon atoms.

[0134] Preferred alkyl groups are methyl, ethyl, propyl, butyl, pentyl, hexyl, heptyl, or octyl. To further reduce viscosity, preferred alkyl groups are methyl, ethyl, propyl, butyl, or pentyl.

[0135] Preferred alkoxy groups are methoxy, ethoxy, propoxy, butoxy, pentoxy, hexoxy, or heptoxy. To further reduce viscosity, methoxy or ethoxy groups are preferred.

[0136] Preferred alkenyl groups are vinyl, 1-propenyl, 2-propenyl, 1-butenyl, 2-butenyl, 3-butenyl, 1-pentenyl, 2-pentenyl, 3-pentenyl, 4-pentenyl, 1-hexenyl, 2-hexenyl, 3-hexenyl, 4-hexenyl, or 5-hexenyl. To reduce viscosity, vinyl, 1-propenyl, 3-butenyl, or 3-pentenyl alkenyl groups are further preferred. The preferred stereoconfiguration of -CH=CH- in these alkenyl groups depends on the position of the double bond. For the purpose of reducing viscosity, the trans configuration is preferred among alkenyl groups such as 1-propenyl, 1-butenyl, 1-pentenyl, 1-hexenyl, 3-pentenyl, and 3-hexenyl. The cis configuration is preferred among alkenyl groups such as 2-butenyl, 2-pentenyl, and 2-hexenyl.

[0137] Preferred alkenyloxy groups are vinyloxy, allyloxy, 3-butenyloxy, 3-pentenyloxy, or 4-pentenyloxy. To reduce viscosity, allyloxy or 3-butenyloxy groups are further preferred.

[0138] Preferred examples of an alkyl group with at least one hydrogen atom substituted by fluorine or chlorine are fluoromethyl, 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, 5-fluoropentyl, 6-fluorohexyl, 7-fluoroheptyl, or 8-fluorooctyl. Further preferred examples for improving dielectric anisotropy are 2-fluoroethyl, 3-fluoropropyl, 4-fluorobutyl, or 5-fluoropentyl.

[0139] Preferred examples of an alkenyl group substituted with at least one hydrogen atom by fluorine or chlorine are 2,2-difluorovinyl, 3,3-difluoro-2-propenyl, 4,4-difluoro-3-butenyl, 5,5-difluoro-4-pentenyl, or 6,6-difluoro-5-hexenyl. For reducing viscosity, 2,2-difluorovinyl or 4,4-difluoro-3-butenyl are further preferred examples.

[0140] Ring A 1 It is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, or tetrahydropyran-2,5-diyl. To improve optical anisotropy or dielectric anisotropy, ring A is preferred. 1It is 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,6-difluoro-1,4-phenylene. Ring C 2 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl. To increase the upper temperature limit, cyclic C is preferred. 2 The preferred form is 1,4-cyclohexylene, and to improve optical anisotropy, the ring C is preferred. 2 The preferred form is 1,4-phenylene, and to improve dielectric anisotropy, cyclic C is preferred. 2 It is 2-fluoro-1,4-phenylene or 2,6-difluoro-1,4-phenylene. Ring C 3 and ring D 3 It is 1,4-cyclohexylene, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene. To reduce viscosity or to increase the upper temperature limit, cyclohexylene is preferred. 3 or ring D 3 The preferred form is 1,4-cyclohexylene, with cyclic C preferred to improve optical anisotropy or to lower the lower limit temperature. 3 or ring D 3 It is 1,4-phenylene or 2-fluoro-1,4-phenylene.

[0141] In ring A 1 and ring C 2 In this context, tetrahydropyran-2,5-dimethyl is...

[0142] [Chemistry 19]

[0143]

[0144] [Chemistry 20]

[0145] Preferred

[0146] [Chemistry 21]

[0147]

[0148] Z 11 It is a single bond, carbonyl oxy group, or difluoromethylene oxy group. To reduce viscosity, Z is preferred. 11 For single bonds, to improve dielectric anisotropy, Z is preferred. 11 It is a carbonyloxy group or a difluoromethyleneoxy group. Z 21 It can be a single bond, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy. For reducing viscosity, Z is preferred. 21 For single bonds, to improve dielectric anisotropy, Z is preferred.21 It is a difluoromethyleneoxy group. Z 31 It can be a single bond, ethylidene, vinylidene, ethynylidene, methyleneoxy, or carbonyloxy. For reducing viscosity, Z is preferred. 31 It is a single key.

[0149] X 11 and X 12 It is either hydrogen or fluorine. X is preferred for reducing viscosity. 11 or X 12 For hydrogen, in order to improve dielectric anisotropy, X is preferred. 11 or X 12 It is fluorine. X 21 and X 22 It is either hydrogen or fluorine. To improve dielectric anisotropy, X is preferred. 21 or X 22 It is fluorine.

[0150] Y 21 It is fluorine, chlorine, an alkyl group having 1 to 12 carbon atoms substituted with at least one hydrogen atom by fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms substituted with at least one hydrogen atom by fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms substituted with at least one hydrogen atom by fluorine or chlorine. To improve dielectric anisotropy, Y is preferred. 21 It is fluorine, at least one hydrogen-substituted alkyl group having 1 to 12 carbon atoms, or at least one hydrogen-substituted alkoxy group having 1 to 12 carbon atoms.

[0151] A preferred example of an alkyl group in which at least one hydrogen atom is substituted with fluorine or chlorine is trifluoromethyl. A preferred example of an alkoxy group in which at least one hydrogen atom is substituted with fluorine or chlorine is trifluoromethoxy.

[0152] n1 is 1 or 2. To reduce viscosity, n1 is preferably 1; to increase the upper temperature limit or to improve optical anisotropy, n1 is preferably 2. n2 is 1, 2, 3, or 4. To reduce viscosity, n2 is preferably 1 or 2; to improve dielectric anisotropy, n2 is preferably 3 or 4. n3 is 1, 2, or 3. To reduce viscosity, n3 is preferably 1; to increase the upper temperature limit or to improve optical anisotropy, n3 is preferably 2 or 3.

[0153] Fifth, preferred additives and ingredient compounds are shown.

[0154] The first additive is at least one selected from compounds (Ch1) and (Ch2), preferably compound (Ch1). At least one of the first additives is preferably compound (Ch1-2), compound (Ch1-3), or compound (Ch1-4). The most preferred optically active compound is compound (Ch1-4). In this case, R 1 and R 2Preferably, it is an alkyl group having 1 to 10 carbon atoms.

[0155] The preferred compounds as second additives are compounds (M1-1) to (M1-5). In compounds (M1-1) to (M1-5), R... a R b Y, Z M Relative to R in compound (M1) a R b Y, Z M For the same meaning, the preferred range is also the same. In compounds (M1-1) to (M1-5), X M1 Preferably, it is a halogen, an alkyl group having 1 to 5 carbon atoms, a polymerizable group represented by formulas (P-1) to (P-6), or an alkyl group having 1 to 5 carbon atoms substituted with a polymerizable group represented by formulas (P-1) to (P-6), more preferably fluorine, methyl, or a polymerizable group represented by formulas (P-1) to (P-6). f is preferably 0, 1, or 2, more preferably 0 or 1. g is preferably 0, 1, or 2, more preferably 0 or 1. h is preferably 0 or 1. In compounds (M1-1) to (M1-5), X M1 The total number is preferably 0 to 3, more preferably 0 to 2, and even more preferably 0 to 1.

[0156] As a second additive, compounds (M1-1) to (M1-3) are preferred, compounds (M1-1) or (M1-2) are more preferred, and compound (M1-1) is particularly preferred.

[0157] As a preferred example of compound (M1), compounds represented by any of the following formulas can be listed. In the following formulas, R a R b Y, X M1 R in equations (M1-1) to (M1-5) respectively a R b Y, X M1 For the same meaning, the preferred range is also the same.

[0158] [Chemistry 22]

[0159]

[0160] [Chemistry 23]

[0161]

[0162] [Chemistry 24]

[0163]

[0164] The preferred compounds as the first component are compounds (1-1) to compounds (1-9). Among these compounds, at least one is preferably compound (1-3), compound (1-7), or compound (1-8). Compound (1-3) is more preferred.

[0165] The preferred compounds as the second component are compounds (2-1) to (2-38). Among these compounds, at least one is preferably compound (2-9), compound (2-15), compound (2-19), compound (2-20), compound (2-30), compound (2-31), or compound (2-37). Compound (2-30) or compound (2-31) is more preferred.

[0166] The preferred compounds as the third component are compounds (3-1) to (3-20). Among these compounds, at least one is preferably compound (3-1), compound (3-2), compound (3-9), compound (3-10), compound (3-15), compound (3-16), compound (3-17), compound (3-19), or compound (3-20).

[0167] Sixth, additives that can be added to the composition are described. Such additives include polymerization initiators, optically active compounds other than compounds (Ch1) and (Ch2), antioxidants, ultraviolet absorbers, pigments, defoamers, polymerizable compounds other than compound (M1), polymerization inhibitors, polar compounds, etc.

[0168] When a polymerization initiator is added to the composition, a photoradical polymerization initiator, a thermal radical polymerization initiator, a photocationic polymerization initiator, etc., can be selected as appropriate based on the polymerizable groups possessed by the compound (M1) or other polymerizable compounds.

[0169] Examples of photoradical polymerization initiators include: DAROCUR 1173 and 4265 (both trade names, BASF Japan), IRGACURE 184, 369, 500, 651, 784, 819, 907, 1300, 1700, 1800, 1850, and 2959 (all trade names, BASF Japan).

[0170] Preferred examples of thermal free radical polymerization initiators include: benzoyl peroxide, diisopropyl peroxide dicarbonate, tert-butyl peroxide-2-ethylhexanoate, tert-butyl peroxide trimethylacetate, tert-butyl peroxide diisobutyrate, lauroyl peroxide, dimethyl 2,2'-azobisisobutyric acid dimethyl (MAIB), di-t-butyl peroxide (DTBPO), azodiisobutyronitrile (AIBN), and azobis cyclohexane carbonitrile (ACN).

[0171] Examples of photocationic polymerization initiators include diaryl iodonium salt (hereinafter referred to as "DAS") and triaryl sulfonium salt (hereinafter referred to as "TAS").

[0172] Examples of DAS include: diphenyliodotetrafluoroborate, diphenyliodohexafluorophosphate, diphenyliodohexafluoroarsenate, diphenyliodotrifluoromethanesulfonate, diphenyliodotrifluoroacetate, diphenyliodo-p-toluenesulfonate, diphenyliodotetra(pentafluorophenyl)borate, 4-methoxyphenylphenyliodotetrafluoroborate, 4-methoxyphenylphenyliodohexafluorophosphate, 4-methoxyphenylphenyliodohexafluoroarsenate, 4-methoxyphenylphenyliodotrifluoromethanesulfonate, 4-methoxyphenylphenyliodotrifluoroacetate, and 4-methoxyphenylphenyliodo-p-toluenesulfonate.

[0173] In DAS, sensitivity can also be increased by adding photosensitizers such as thioxanthrone, phenothiazine, chlorothioxanthrone, oxanthrone, anthracene, diphenylanthracene, and rubrene.

[0174] Examples of TAS (Toluene Sulfate Ascorbate) include: triphenylsulfonium tetrafluoroborate, triphenylsulfonium hexafluorophosphate, triphenylsulfonium hexafluoroarsenate, triphenylsulfonium trifluoromethanesulfonate, triphenylsulfonium trifluoroacetate, triphenylsulfonium-p-toluenesulfonate, triphenylsulfonium tetra(pentafluorophenyl)borate, 4-methoxyphenyl diphenylsulfonium tetrafluoroborate, 4-methoxyphenyl diphenylsulfonium hexafluorophosphate, 4-methoxyphenyl diphenylsulfonium hexafluoroarsenate, 4-methoxyphenyl diphenylsulfonium trifluoromethanesulfonate, 4-methoxyphenyl diphenylsulfonium trifluoroacetate, 4-methoxyphenyl diphenylsulfonium-p-toluenesulfonate, etc.

[0175] Examples of specific trade names for photocationic polymerization initiators include: Cyracure UVI-6990, Cyracure UVI-6974, and Cyracure UVI-6992 (trade names, UCC, Inc.), Adeka Optomer SP-150, SP-152, SP-170, and SP-172 (trade names, ADEKA, Inc.), Rhodorsil Photoinitiator 2074 (trade name, Rhodia Japan, Inc.), IRGACURE 250 (trade name, BASF Japan, Inc.), and UV-9380C (trade name, GE Toshiba Silicone, Inc.), etc.

[0176] From the viewpoint of obtaining higher contrast, the amount of polymerization initiator added relative to the main liquid crystal composition is preferably 0.1% by mass or less, more preferably 0.05% by mass or less, further preferably 0.03% by mass or less, and particularly preferably 0.01% by mass or less. The cholesterol-type liquid crystal composition of the present invention may also not contain a polymerization initiator.

[0177] Examples of optically active compounds other than compounds (Ch1) and (Ch2) include compounds (5-1) to (5-5). The preferred proportion of the optically active compounds other than compounds (Ch1) and (Ch2) relative to the main liquid crystal composition is about 5% by mass or less. More preferably, the proportion is in the range of about 0.0% by mass to about 2.0% by mass. The cholesterol-type liquid crystal composition of the present invention possesses suitable properties even without the addition of optically active compounds other than compounds (Ch1) and (Ch2).

[0178] [Chemistry 25]

[0179]

[0180] As polymeric compounds other than compound (M1), examples include compounds having polymeric groups represented by formulas (P-1) to (P-6). These compounds may have mesocrystalline sites or not. Specifically, for polymeric compounds other than compound (M1), please refer to paragraphs 0141 to 0159 of Japanese Patent Application Publication No. 2019-214698. The cholesterol-type liquid crystal composition of the present invention preferably has a total content of polymeric compounds (including compound (M1)) of less than 2.0% by mass relative to the main liquid crystal composition. Furthermore, it is preferably 0.1% by mass or more. The cholesterol-type liquid crystal composition of the present invention possesses suitable properties even without the addition of polymeric compounds other than compound (M1).

[0181] To prevent a decrease in resistivity caused by heating in the atmosphere, or to maintain a high voltage retention rate not only at room temperature but also at temperatures close to the upper limit after prolonged use of the component, antioxidants such as compounds (6-1) to (6-3) may be added to the composition.

[0182] [Chemistry 26]

[0183]

[0184] Compound (6-2) is effective in maintaining a high voltage retention rate not only at room temperature but also at temperatures close to the upper limit temperature after prolonged use of the component. To achieve this effect, the preferred proportion of the antioxidant is about 50 ppm or more, and to avoid lowering the upper limit temperature or raising the lower limit temperature, the preferred proportion of the antioxidant is about 600 ppm or less. More preferably, the proportion is in the range of about 100 ppm to about 300 ppm.

[0185] Preferred examples of ultraviolet absorbers include benzophenone derivatives, benzoic acid ester derivatives, triazole derivatives, etc. Additionally, light stabilizers such as amines that exhibit steric hindrance are also preferred. Preferred examples of light stabilizers are compounds (7-1) to (7-16), etc. To obtain the aforementioned effect, the preferred proportion of these absorbers or stabilizers is about 50 ppm or more, and to avoid lowering the upper limit temperature or raising the lower limit temperature, the preferred proportion of these absorbers or stabilizers is about 10,000 ppm or less. More preferably, the proportion is in the range of about 100 ppm to about 10,000 ppm.

[0186] [Chemistry 27]

[0187]

[0188] [Chemistry 28]

[0189]

[0190] A matting agent is a compound that prevents the decomposition of a crystalline compound by accepting light energy absorbed by the compound and converting it into heat energy. Preferred examples of matting agents are compounds (8-1) to (8-7), etc. To achieve the aforementioned effect, the preferred proportion of these matting agents is about 50 ppm or more, and to avoid raising the lower limit temperature, the preferred proportion of these matting agents is about 20,000 ppm or less. More preferably, the proportion is in the range of about 100 ppm to about 10,000 ppm.

[0191] [Chemistry 29]

[0192]

[0193] Seventh, the methods for synthesizing the additives and constituent compounds are described. These compounds can be obtained from Sigma-Aldrich Corporation or synthesized using known methods. Compound (M1-1) can be synthesized using the method described in International Publication No. 2015-4947. Compound (Ch1-4) can be synthesized using the method described in International Publication No. 2014-97952. Compounds (1-7) can be synthesized using the method described in Japanese Patent Application Publication No. 10-114733. Compounds (2-19) can be synthesized using the method described in Japanese Patent Application Publication No. 10-251186. Compound (3-1) can be synthesized using the method described in Japanese Patent Application Publication No. 9-77692.

[0194] Compounds for which no synthetic method is described can be synthesized using methods described in the following books: *Organic Syntheses* (John Wiley & Sons, Inc.), *Organic Reactions* (John Wiley & Sons, Inc.), *Comprehensive Organic Synthesis* (Pergamon Press), and *New Lectures in Experimental Chemistry* (Maruzen), etc. The composition is prepared using known methods from compounds obtained in the manner described. For example, the component compounds are mixed and then dissolved into each other by heating.

[0195] Finally, the uses of the composition are described. The compositions of the present invention can be used as cholesterol-type liquid crystal compositions, wherein the cholesterol-type liquid crystal compositions contain optically active compounds as compound (Ch1) or compound (Ch2), and the selective reflection wavelength is in the range of 350 nm to 800 nm. The compositions of the present invention can, as needed, have the aforementioned suitable properties by adjusting the proportions of the component compounds or by mixing with other liquid crystal compounds, and are suitable for liquid crystal elements, particularly reflective liquid crystal elements.

[0196] [Example]

[0197] The invention will be further described in detail with reference to the embodiments. The invention is not limited to these embodiments. The invention includes, for example, mixtures of the compositions of Example 1 and Example 13, as well as mixtures of at least two of the compositions of the examples.

[0198] Measurement Methods: The characteristics are measured using the methods described below. These methods are mostly those described in the JEITA standard (JEITA·ED-2521B) reviewed and formulated by the Japan Electronics and Information Technology Industries Association (JEITA), or modified versions thereof. The twisted nematic (TN) element used in the measurement does not have a thin-film transistor (TFT) installed.

[0199] (1) Upper limit temperature of the nematic phase (NI; °C), upper limit temperature of the cholesterol phase (N*I): The sample is placed on a hot plate of a melting point measuring apparatus including a polarizing microscope and heated at a rate of 1 °C / min. The temperature at which a portion of the sample changes from the nematic or cholesterol phase to an isotropic liquid is measured. Sometimes the upper limit temperature of the nematic or cholesterol phase is simply referred to as the "upper limit temperature".

[0200] (2) Lower limit temperature of nematic or cholesterol phase (T) C (℃): The sample containing the nematic or cholesterol phase is placed in a glass bottle and stored in a freezer at 0℃, -10℃, -20℃, -30℃, and -40℃ for 10 days, after which the liquid crystal phase is observed. For example, when the sample retains the nematic or cholesterol phase at -20℃ and changes to a crystalline or lamellar phase at -30℃, it is recorded as T. C <-20℃. When it changes into a crystalline or layered phase at 0℃ or 25℃ (room temperature), T CThese are recorded as >0℃ and >25℃, respectively. Sometimes, the lower limit temperature of the nematic or cholesterol phase is simply referred to as the "lower limit temperature".

[0201] (3) Viscosity (volume viscosity; η; measured at 25°C; mPa·s): The E-type rotational viscometer manufactured by Tokyo Keiki Co., Ltd. was used for the measurement.

[0202] (4) Viscosity (rotational viscosity; γ1; measured at 25°C; mPa·s): The method described in M. Imai et al., Molecular Crystals and Liquid Crystals, Vol. 259, p. 37 (1995), was used. A sample was placed in a TN element with a twist angle of 0° and a spacing (unit gap) of 5 μm between the two glass substrates. A voltage was applied to the element in stages in 0.5V increments within the range of 16V to 19.5V. After 0.2 seconds without voltage application, the voltage was repeatedly applied under the condition of applying only a rectangular wave (rectangular pulse; 0.2 seconds) and no voltage application (2 seconds). The peak current and peak time of the transient current generated by the application were measured. The rotational viscosity value was obtained based on these measured values ​​and the calculation formula (10) described on p. 40 of M. Imai et al.'s paper. The value of dielectric anisotropy required for the calculation is obtained using an element that measures the rotational viscosity and by the method described below.

[0203] (5) Optical anisotropy (refractive index anisotropy; Δn; measured at 25°C): Measurements were performed using light with a wavelength of 589 nm, employing an Abbe refractometer with a polarizing plate mounted on the eyepiece. The surface of the main prism was rubbed in one direction, and the sample was dropped onto the prism. The refractive index n∥ was measured when the direction of polarization was parallel to the direction of rubbing. The refractive index n⊥ was measured when the direction of polarization was perpendicular to the direction of rubbing. The value of optical anisotropy was calculated using the formula Δn = n∥ - n⊥.

[0204] (6) Dielectric anisotropy (Δε; measured at 25°C): A sample was placed in a TN element with a 9 μm gap (cell gap) between two glass substrates and a twist angle of 80 degrees. A sine wave (10 V, 1 kHz) was applied to the element, and the dielectric constant (ε∥) along the long axis of the liquid crystal molecules was measured after 2 seconds. A sine wave (0.1 V, 1 kHz) was applied to the element, and the dielectric constant (ε⊥) along the short axis of the liquid crystal molecules was measured after 2 seconds. The value of dielectric anisotropy was calculated using the formula Δε = ε∥ - ε⊥.

[0205] (7-1) Threshold voltage (Vth(25); measured at 25°C; V): A Liquid Crystal Display (LCD) 5200 luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for measurement. A halogen lamp was used as the light source. The sample was placed in a fringe field switching (FFS) element with a spacing (cell gap) of 3.2 (μm) between two glass substrates. The voltage (32Hz, rectangular wave) applied to the element was increased stepwise from 0V to 10V in units of 0.01V. At this time, light was irradiated onto the element from the vertical direction, and the amount of light transmitted through the element was measured. A voltage-transmittance curve was prepared with a transmittance of 100% when the light amount was at its maximum and a transmittance of 0% when the light amount was at its minimum. The threshold voltage is expressed as the voltage at which the transmittance reaches 95%.

[0206] (7-2) Threshold voltage (Vth(-30); measured at -30°C; V): same as (7-1) except that it is measured at -30°C.

[0207] (8) Voltage Retention Rate (VHR-1; measured at 25°C; %): The TN element used for the measurement has a polyimide-oriented film, and the spacing (unit gap) between the two glass substrates is 5 μm. After the sample is placed into the element by vacuum injection, the injection port is sealed with an adhesive that is cured by ultraviolet light. The TN element is charged by applying a pulse voltage (1V and 60 microseconds). The decaying voltage is measured over a period of 166.7 milliseconds using a high-speed voltmeter, and the area A between the voltage curve per unit period and the horizontal axis is calculated. Area B is the area before decay. The voltage retention rate is expressed as a percentage of area A relative to area B.

[0208] (9) Voltage retention rate (VHR-2; measured at 60°C; %): The voltage retention rate was determined using the same procedure as described above, except that the measurement was performed at 60°C instead of at 25°C. The obtained value is expressed as VHR-2.

[0209] (10) Voltage retention rate (VHR-3; determined at 60°C; %): The voltage retention rate was determined after irradiation with ultraviolet light, and the stability to ultraviolet light was evaluated. The TN element used for the test had a polyimide oriented film and a unit spacing of 5 μm. The sample was injected into the element and irradiated with 5 mW / cm². 2The UV light was applied for 167 minutes. The light source was a black light, F40T10 / BL (peak wavelength 369nm), manufactured by Eye Graphics Co., Ltd., with a spacing of 5mm between the element and the light source. In the VHR-3 measurement, the decay voltage was measured over a period of 166.7 milliseconds. The composition with a large VHR-3 exhibits high stability against UV light.

[0210] (11) Voltage Retention Rate (VHR-4; determined at 60°C; %): After heating the TN element with the injected sample in a thermostat at 120°C for 20 hours, the voltage retention rate was determined, and the thermal stability was evaluated. In the VHR-4 determination, the decaying voltage was measured over a period of 166.7 milliseconds. Compositions with a large VHR-4 exhibit high thermal stability.

[0211] (12) Voltage retention rate (VHR-5; measured at 60°C; %): The voltage retention rate was measured after the TN element with the injected sample was placed on the backlight for 2 weeks, and the stability to the backlight was evaluated. In the VHR-5 measurement, the decaying voltage was measured over a period of 166.7 milliseconds. Compositions with a large VHR-5 exhibit great stability to the backlight.

[0212] (13) Response time (τ; measured at 25°C; ms): An LCD5200 luminance meter manufactured by Otsuka Electronics Co., Ltd. was used for measurement. The light source was a halogen lamp. The low-pass filter was set to 5 kHz. The sample was placed in a TN element with a spacing (cell gap) of 5 μm between two glass substrates. A rectangular wave (60 Hz, Vth(25), 0.5 s) was applied to the element. At this time, light was irradiated onto the element from the vertical direction, and the amount of light reflected by the element was measured. The reflectance was considered to be 100% when the amount of light reached its maximum and 0% when the amount of light reached its minimum. Rise time (τr: risetime; milliseconds) is the time required for the reflectance to change from 90% to 10%. Fall time (τf: fall time; milliseconds) is the time required for the reflectance to change from 10% to 90%. The response time is expressed as the sum of the rise time and fall time calculated in the manner described above. For the element after the sample is injected, a voltage is applied in 1V increments from 0V to 40V, and the voltage that switches from the initial reflection state to the transmission state is defined as Vreset(V).

[0213] (14) Elastic constant (K; measured at 25°C; pN): An HP4284A inductance-capacitance-resistance (LCR) meter manufactured by Yokogawa-Hewlett-Packard Co., Ltd. was used for measurement. A sample was placed in a horizontally aligned element with a spacing (cell gap) of 20 μm between two glass substrates. A charge of 0 to 20 volts was applied to the element, and the electrostatic capacitance and applied voltage were measured. The measured electrostatic capacitance (C) and applied voltage (V) values ​​were fitted using equations (2.98) and (2.101) on page 75 of the *Liquid Crystal Devices Handbook* (Nikkan Kogyo Shimbun Co., Ltd.), and the values ​​of K11 and K33 were obtained according to equation (2.99). Next, K22 was calculated using the previously obtained values ​​of K11 and K33 in equation (3.18) on page 171 of the *Liquid Crystal Devices Handbook* (Nikkan Kogyo Shimbun Co., Ltd.). The elastic constant is represented by the average value of K11, K22, and K33 obtained in the manner described above.

[0214] (15) Specific resistance (ρ; measured at 25°C; Ωcm): 1.0 mL of the sample is injected into a container including the electrodes. A DC voltage (10V) is applied to the container, and the DC current is measured after 10 seconds. The specific resistance is calculated according to the following formula: (Specific resistance) = {(voltage) × (capacitance of the container)} / {(DC current) × (dielectric constant of vacuum)}.

[0215] (16) Helix pitch (P; measured at room temperature; μm): The helix pitch is measured using the wedge method. Refer to page 196 of "Liquid Crystal Handbook" (published in 2000, Maruzen). The sample is injected into the wedge unit and left to stand at room temperature for 2 hours. The spacing (d2-d1) of the discclination lines is then observed using a polarizing microscope (Nikon, MM40 / 60 series). The helix pitch (P) is calculated using the following formula, which expresses the angle of the wedge unit as θ: P = 2 × (d2-d1) × tanθ.

[0216] (17) Dielectric constant in the short axis direction (ε⊥; measured at 25°C): The sample was placed in a TN element with a spacing (cell gap) of 9 μm between two glass substrates and a twist angle of 80 degrees. A sine wave (0.1 V, 1 kHz) was applied to the element, and the dielectric constant (ε⊥) in the short axis direction of the liquid crystal molecules was measured after 2 seconds.

[0217] (18) Frequency dependence of dielectric anisotropy (F10; measured at -20°C): A sample was placed in a TN element with a spacing (cell gap) of 9 μm between two glass substrates and a twist angle of 80 degrees. A sine wave (0.5V, 20Hz, 50Hz, 100Hz, 1kHz, 5kHz, 10kHz, 50kHz, 100kHz, 500kHz, 1000kHz, 500kHz, 1000kHz) was applied to the element, and the dielectric constant (ε⊥) of the liquid crystal molecules in the short axis direction was measured after 2 seconds. The frequency at which the dielectric anisotropy decreased by 10% relative to the dielectric anisotropy at 20Hz was defined as F10. The larger the F10, the smaller the frequency dependence.

[0218] (19) Selected Reflection Wavelength (λ; nm) and Reflectivity (%): A JASCO V-700 UV-Vis-NIR spectrophotometer equipped with an ISV-922 integrating sphere was used for the measurements. The sample was placed in an element with a 5 μm gap (unit gap) between two glass substrates, and the reflection wavelength was measured at a light incident angle of 5 degrees. After applying a voltage of 40 V to the element, the reflectivity at each wavelength was measured when the voltage returned to 0 V. The wavelength representing the maximum reflectivity was defined as the selected reflection wavelength (40 V), and the reflectivity at the selected reflection wavelength (40 V) was defined as the highest reflectivity (reflectivity max). After applying a voltage of 20 V to the element, the reflectivity at each wavelength was measured when the voltage returned to 0 V. The reflectivity at the selected reflection wavelength (40 V) was defined as the lowest reflectivity (reflectivity min). The contrast ratio (CR) was calculated using the following formula: CR = reflectivity max / reflectivity min.

[0219] (20) The temperature change of the selected reflection wavelength is to measure the difference (nm) between 25℃ and 60℃.

[0220] Examples of the cholesterol-type liquid crystal compositions of the present invention are shown below.

[0221] In the following, liquid crystal compounds are represented by symbols based on the definitions in Table 2 below. In Table 2, the stereoconfiguration associated with 1,4-cyclohexylene is the trans configuration. The number in parentheses following the symbolized compound indicates the chemical formula to which the compound belongs. The symbol (-) indicates other liquid crystal compounds. The proportion (percentage) of liquid crystal compounds is a mass percentage (mass %) based on the mass of the main nematic liquid crystal composition excluding additives.

[0222] [Table 2]

[0223] Table 2. Representation of compounds using notations

[0224] R-(A1)-Z1-·····-Z n -(A n )-R'

[0225]

[0226] [Examples 1 to 6 and Comparative Examples 1 to 7]

[0227] Optically active compounds, polymerizable compounds, and other additives were added to the main liquid crystal composition A in the proportions shown in Table 3 to prepare cholesterol-type liquid crystal compositions of Examples 1 to 6 and Comparative Examples 1 to 7, and their properties were evaluated. The results are shown in Table 3. Furthermore, those listed as "(main liquid crystal composition)" in Table 3 represent the evaluation results of main liquid crystal composition A.

[0228] (Main liquid crystal composition A)

[0229]

[0230]

[0231] In Tables 3 and 4, blank columns for additives or related additives indicate that no additives were added, and blank columns for evaluation indicate that no evaluation (determination) was performed.

[0232] The components in Tables 3 and 4 are as follows.

[0233] [Chemistry 30]

[0234]

[0235] [Table 3]

[0236]

[0237] As shown in Table 3, a high contrast ratio (CR ≥ 2.00) can be obtained by using compound (M1) at less than 2% by mass relative to the main liquid crystal composition. Furthermore, in examples where optically active compounds other than those equivalent to compound (Ch1) or compound (Ch2) were used, the reflection wavelength varied significantly, resulting in a low contrast ratio.

[0238] [Examples 7-13 and Comparative Example 8]

[0239] Relative to each host liquid crystal composition, compounds (Ch1-1-1) and (M1-1-1) were added to each of the host liquid crystal compositions described below in the proportions shown in Table 4 to prepare cholesterol-type liquid crystal compositions of Examples 7 to 13 and Comparative Example 8, and their properties were evaluated. The results are shown in Table 4. Furthermore, those listed as "(host liquid crystal composition)" in Table 4 represent the evaluation results of each host liquid crystal composition.

[0240] (Main liquid crystal composition: Comparative Example 8)

[0241]

[0242] (Main liquid crystal composition: Example 7)

[0243]

[0244] (Main liquid crystal composition: Example 8)

[0245]

[0246]

[0247] (Main liquid crystal composition: Example 9)

[0248]

[0249] (Main liquid crystal composition: Example 10)

[0250]

[0251] (Main liquid crystal composition: Example 11)

[0252]

[0253] (Main liquid crystal composition: Example 12)

[0254]

[0255] (Main liquid crystal composition: Example 13)

[0256]

[0257]

[0258] [Table 4]

[0259]

[0260] As shown in Tables 3 and 4, the viscosity of the other examples containing compound (1) is lower than that of Comparative Example 8, which does not contain compound (1). In addition, it is shown that cholesterol-type liquid crystal compositions with high contrast and other excellent properties can be obtained in various compositions containing compound (1), compound (2) and compound (3) and compound (Ch1) or compound (Ch2) and compound (M1).

[0261] [Industry availability]

[0262] The cholesterol-type liquid crystal composition of the present invention can be used to manufacture a cholesterol-type liquid crystal composition with high contrast and short response time.

Claims

1. A cholesterol-type liquid crystal composition comprising: a host liquid crystal composition, said host liquid crystal composition comprising, as a first component, at least one compound selected from compounds represented by formula (1); and, as a first additive, at least one optically active compound selected from compounds represented by formulas (Ch1) and (Ch2); and, as a second additive, at least one polymerizable compound selected from compounds represented by formula (M1). Based on the mass of the main liquid crystal composition, the content of the second additive is less than 2.0% by mass. [Chemistry 1] In equation (1), R 11 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; cyclic A 1 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 11 It is a single bond, a carbonyl group, or a difluoromethylene group; X 11 and X 12 It is hydrogen or fluorine; n1 is 1 or 2; In equations (Ch1) and (Ch2), R 1 R 2 and R 3 It is hydrogen, halogen, cyano, -SF5, or an alkyl group having 1 to 10 carbon atoms, wherein at least one -CH2- may be substituted with -O-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and wherein at least one hydrogen atom may be substituted with fluorine or chlorine; ring A, ring B, ring E, and ring F are 5,6,7,8-tetrahydronaphthyl-1,2-diyl or naphthyl-1,2-diyl; ring C, ring D, and ring G are 1,4-cyclohexene, 1,4-phenylene, 1,3-dioxane-2,5-diyl, tetrahydropyran-2,5-diyl, tetrahydropyran-3,5-diyl, pyrimidin-2,5-diyl, pyridine-2,5-diyl, or 1,4-bicyclo-(2,2,2)-octylene, wherein at least one hydrogen atom may be substituted with fluorine or chlorine; Z 1 Z 2 Z 3 Z 4 and Z 5 It is a single bond or an alkylene group having 1 to 20 carbon atoms, wherein at least one -CH2- group may be substituted with -O-, -CO-, -COO-, -OCO-, -CH=CH-, or -C≡C-, and wherein at least one hydrogen atom may be substituted with fluorine or chlorine; a, b, and c are 2, 3, or 4; In equation (M1), R a and R b The polymerizable group, hydrogen, halogen, -C≡N, -N=C=O, or -N=C=S, R, represented by any of formulas (P-1) to (P-6) a and R b At least one of them is the polymeric group, [Chemistry 2] In equations (P-1) to (P-6), M 1 To M 3 It is hydrogen, fluorine, an alkyl group having 1 to 5 carbon atoms, or at least one hydrogen-substituted fluorine alkyl group having 1 to 5 carbon atoms, in the M 1 To M 3 In this case, at least one -CH2- of the alkyl group may be substituted via -O-; A M1 and A M2 A divalent group formed by removing hydrogen from two aromatic rings, wherein at least one hydrogen may be substituted by a halogen, an alkyl group having 1 to 5 carbon atoms, a alkyl halide having 1 to 5 carbon atoms, at least one -CH2- substituted with -O- or -COO- of an alkyl group having 1 to 5 carbon atoms, a polymerizable group represented by any of formulas (P-1) to (P-6), an alkyl group having 1 to 5 carbon atoms substituted by a polymerizable group represented by any of formulas (P-1) to (P-6), or an alkyl halide having 1 to 5 carbon atoms substituted by a polymerizable group represented by any of formulas (P-1) to (P-6); Y M1 and Y M2 It is a single bond or an alkylene group having 1 to 12 carbon atoms, wherein at least one -CH2- may be substituted with -O- or -S-, and at least one -CH2-CH2- may be substituted with -CH=CH-, -C≡C-, -COO-, or -OCO-; Y M1 and Y M2 At least one of them is a single bond, or at least one -CH2- alkylene group having 1 to 4 carbon atoms that can be substituted via -O-; Z M It is a single bond, -(CH2) m2 -、-O(CH2) m2 -、-(CH2) m2 O-, -O(CH2) m2 O-, -CH=CH-, -C≡C-, -COO-, -OCO-, -(CF2)2-, -(CH2)2-COO-, -OCO-(CH2)2-, -CH=CH-COO-, -OCO-CH=CH-, -C≡C-COO-, -OCO-C≡C-, -CH=CH-(CH2)2-, -(CH2)2-CH=CH-, -CF=CF-, -C≡C-CH=CH-, -CH=CH-C≡C-, -OCF2-(CH2)2-, -(CH2)2-CF2O-, -OCF2-, or -CF2O- (in the above formulas, m2 is 1 or 2); m1 is an integer from 1 to 5.

2. The cholesterol-type liquid crystal composition according to claim 1, wherein the polymerizable group represented by any one of formulas (P-1) to (P-6) included in formula (M1) is two or three, R a and R b All of them are polymeric groups represented by any one of formulas (P-1) to (P-6).

3. The cholesterol-type liquid crystal composition according to claim 1, wherein the total content of polymeric compounds is less than 2.0% by mass based on the mass of the host liquid crystal composition.

4. The cholesterol-type liquid crystal composition according to claim 1, wherein Y M1 and Y M2 It is a single bond or an alkylene group having 1 to 8 carbon atoms, wherein at least one -CH2- may be substituted with -O- or -S-, and at least one -CH2-CH2- may be substituted with -CH=CH-, -C≡C-, -COO-, or -OCO-, Y M1 and Y M2 At least one of them is a single bond, or at least one -CH2- alkylene group having 1 to 4 carbon atoms that can be substituted by -O-.

5. The cholesterol-type liquid crystal composition according to claim 1, comprising, as a second additive, at least one polymerizable compound selected from compounds represented by formulas (M1-1) to (M1-5). [Chemistry 3] In equations (M1-1) to (M1-5), R a R b Y, Z M respectively with R in equation (M1) a R b Y, Z M They have the same meaning. X M1 The following are possible meanings: halogen, alkyl group having 1 to 5 carbon atoms, alkyl halide having 1 to 5 carbon atoms, at least one alkyl group having 1 to 5 carbon atoms substituted with -CH2- or -O- or -COO-, a polymerizable group represented by any of formulas (P-1) to (P-6), at least one alkyl group having 1 to 5 carbon atoms substituted with a polymerizable group represented by any of formulas (P-1) to (P-6), or at least one alkyl halide having 1 to 5 carbon atoms substituted with a polymerizable group represented by any of formulas (P-1) to (P-6), X M2 It is hydrogen or methyl, f is 0, 1, 2, 3, or 4, g is 0, 1, 2, or 3, and h is 0, 1, or 2.

6. The cholesterol-type liquid crystal composition according to claim 1, wherein the content of the polymerization initiator is less than 0.1% by mass based on the mass of the host liquid crystal composition.

7. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, comprising, as a first additive, at least one optically active compound selected from the compounds represented by formulas (Ch1-1) to (Ch1-6) and (Ch2-1) to (Ch2-3). [Chemistry 4] [Chemistry 5] In equations (Ch1-1) to (Ch1-6) and equations (Ch2-1) to (Ch2-3), R 1 R 2 and R 3 It is hydrogen, halogen, cyano, -SF5, or an alkyl group having 1 to 10 carbon atoms, wherein at least one -CH2- group may be substituted with -O-, -COO-, -OCO-, -CH=CH-, or -C≡C-, wherein at least one hydrogen atom may be substituted with fluorine or chlorine; ring A, ring B, ring E, and ring F are 5,6,7,8-tetrahydronaphthalene-1,2-diyl or naphthalene-1,2-diyl.

8. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, wherein the content of the first additive is in the range of 0.1% by mass to 10% by mass based on the mass of the host liquid crystal composition.

9. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, comprising as a first component at least one compound selected from the compounds represented by formulas (1-1) to (1-9), [Chemistry 6] In equations (1-1) to (1-9), R 11 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; X 11 and X 12 It is either hydrogen or fluorine.

10. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, wherein the content of the first component is in the range of 5% by mass to 30% by mass based on the mass of the host liquid crystal composition.

11. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, wherein the main liquid crystal composition further comprises, as a second component, at least one compound selected from the compounds represented by formula (2). [Chemistry 7] In equation (2), R 21 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms; cyclic C 2 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, 2,6-difluoro-1,4-phenylene, pyrimidin-2,5-diyl, 1,3-dioxane-2,5-diyl, or tetrahydropyran-2,5-diyl; Z 21 For single bonds, ethylene, vinylene, carbonyloxy, or difluoromethyleneoxy; X 21 and X 22 It is hydrogen or fluorine; Y 21 It is fluorine, chlorine, an alkyl group having 1 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine, an alkoxy group having 1 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine, or an alkenyloxy group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine; n2 is 1, 2, 3, or 4.

12. The cholesterol-type liquid crystal composition according to claim 11, comprising as a second component at least one compound selected from compounds represented by formulas (2-1) to (2-38), [Chemistry 8] [Chemistry 9] [Chemistry 10] [Chemistry 11] [Chemistry 12] In equations (2-1) to (2-38), R 21 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms.

13. The cholesterol-type liquid crystal composition according to claim 11, wherein the content of the second component is in the range of 5% by mass to 50% by mass, based on the mass of the main liquid crystal composition.

14. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, wherein the main liquid crystal composition further comprises, as a third component, at least one compound selected from the compounds represented by formula (3). [Chemistry 13] In equation (3), R 31 and R 32 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine; cyclic C 3 and ring D 3 It is 1,4-cyclohexene, 1,4-phenylene, 2-fluoro-1,4-phenylene, or 2,5-difluoro-1,4-phenylene; Z 31 n is a single bond, ethylidene, vinylidene, ethynylidene, methyleneoxy, or carbonyloxy; n3 is 1, 2, or 3.

15. The cholesterol-type liquid crystal composition according to claim 14, further comprising, as a third component, at least one compound selected from the compounds represented by formulas (3-1) to (3-20). [Chemistry 14] [Chemistry 15] In equations (3-1) to (3-20), R 31 and R 32 It is an alkyl group having 1 to 12 carbon atoms, an alkoxy group having 1 to 12 carbon atoms, an alkenyl group having 2 to 12 carbon atoms, or an alkenyl group having 2 to 12 carbon atoms that has at least one hydrogen atom substituted with fluorine or chlorine.

16. The cholesterol-type liquid crystal composition according to claim 14, wherein the content of the third component ranges from 10% by mass to 90% by mass based on the mass of the main liquid crystal composition.

17. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, wherein the optical anisotropy of the main liquid crystal composition at a wavelength of 589 nm (measured at 25°C) is in the range of 0.10 to 0.40, and the dielectric anisotropy of the main liquid crystal composition at a frequency of 1 kHz (measured at 25°C) is in the range of 10 to 100.

18. The cholesterol-type liquid crystal composition according to any one of claims 1 to 6, wherein the reflection wavelength is selected in the range of 350 nm to 800 nm.

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