TW201819601A - Compound, liquid crystal medium containing the compound, and display unit effectively reducing startup voltage and increasing the degree of penetration of the display unit - Google Patents

Abstract

A liquid crystal medium which comprises at least one compound I represented by chemical formula 1. The definitions of R1, R2, X1, X2, A1, A2, A3, A4, n, m, and o in the chemical formula 1 are as described in the specification and the claims of the patent application. The present invention also refers to a compound represented by the chemical formula 1, and a display unit containing the liquid crystal medium. Since the liquid crystal medium of the present invention contains the compound I represented by the chemical formula 1 having higher [DELTA][epsilon] and [epsilon]&bottom, when it is subsequently applied to a liquid crystal display unit, it can effectively reduce the startup voltage and increase the degree of penetration.

Description

Compound, liquid crystal medium and display unit containing the same

The present invention relates to a compound, a liquid crystal medium and a display unit containing the compound, and particularly to a compound represented by Chemical Formula 1, a liquid crystal medium and a display unit containing the compound.

In response to the wide use of liquid crystal display units, various properties of liquid crystal compounds, such as dielectric anisotropy (Δε), refractive anisotropy (Δn), and rotational viscosity (γ1), are still required to be continuously improved, so Currently, the industry still needs to research and develop novel liquid crystal compounds or liquid crystal media.

United States Patent Publication US 2009/0066905 A1 discloses a compound containing a benzodioxane (dioxatetralin) group, which has the following structure (A): (A) In the above structure (A), G ¹ and G ² represent cyano, halo, optionally substituted hydrocarbyl, selectively substituted alkoxy, selectively substituted heterocyclyl, RC (O) O- or ROC (O)-, wherein R represents a selectively substituted hydrocarbon group; G ³ , G ⁴ and G ⁵ represent hydrogen, halogen, CF ₃ or SF _{5 respectively} ; Y ¹ , Y ² , Y ³ And Y ⁴ represent a single bond, -CH ₂ CH ₂ -,-(CH ₂ ) _4- , -CH ₂ O-, -CH = CH-, -C≡C-, -COO-, -OCO-, or- OCH _2- ; E ¹ , E ² , E ³ and E ⁴ respectively represent 1,4-phenylene, 1,4-cyclohexyl or heterocyclo, the aforementioned groups are optionally substituted; and t1 t2, t3, and t4 are 0 or 1, respectively, provided that t1 + t2 + t3 + t4 is greater than 0; when t1 is 0, t2 is 0; and when t3 is 0, t4 is 0. In most embodiments of this U.S. Patent Publication, t3 = t4 = 0 of the structure (A), or one of t3 and t4 is 1 and the other is 0. Most of the compounds in the examples have Δε <0, which shows that the compounds in this US patent are mainly negative liquid crystals.

Therefore, the object of the present invention is to provide a liquid crystal medium that can achieve at least one of the following effects: reducing the startup voltage of the display, shortening the response time, and increasing the penetration.

Therefore, the liquid crystal medium of the present invention includes: at least one compound I represented by Chemical Formula 1: [Chemical Formula 1] In Chemical Formula 1, R ¹ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 One or more hydrogens in the alkyl, alkoxy, alkenyl, or alkenyl group may be optionally substituted with fluorine; X ¹ and X ² each represent hydrogen or fluorine; A ¹ , A ² , A ³ and A ⁴ each represent 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene Phenyl or 3-fluoro-1,4-phenylene; n represents 0, 1, or 2, when n is 2, two A ² may be the same or different; m and o represent 0 or 1, and m + o≥1; and R ² represents halogen, OCF ₃ , CF ₃ or CN.

Another object of the present invention is to provide a compound represented by the chemical formula 1, which is a positive-type liquid crystal compound, and has a higher Δε, a higher ε _⊥ , and a suitable γ1, and is resistant to acids, heat, and ultraviolet rays. The nature of light is stable.

Yet another object of the present invention is to provide a display unit including the aforementioned liquid crystal medium.

The effect of the present invention is that the liquid crystal medium of the present invention has a special structure design and has a high compound Δε and ε _化合物 of compound I shown in Chemical Formula 1. When it is subsequently applied to a liquid crystal display unit, it can effectively reduce at least the startup voltage and increase the penetration. degree.

The following describes the content of the present invention in detail:

Preferably, the compound I is selected from a compound represented by Chemical Formula 1-1, a compound represented by Chemical Formula 1-2, or a compound represented by Chemical Formula 1-3: [Chemical Formula 1-1] , [Chemical Formula 1-2] [Chemical Formula 1-3] .

Preferably, in the chemical formulae 1-1, 1-2 and 1-3, A ¹ , A ² , A ³ and A ⁴ each represent 1,4-cyclohexyl, 1,4-phenylene, 3 1,5-difluoro-1,4-phenylene or 3-fluoro-1,4-phenylene; R ¹ represents an alkyl group having a carbon number of 1 to 10 or an alkoxy group having a carbon number of 1 to 10 And R ² represents halogen, OCF ₃ , CF ₃ or CN.

In a specific example of the present invention, the compound I is represented by Chemical Formula 1-2 and the compound represented by Chemical Formula 1-2 is selected from the group consisting of: [Chemical Formula 1-2A] , [Chemical Formula 1-2B] And [chemical formula 1-2C] .

Preferably, in the chemical formulae 1-2A, 1-2B and 1-2C, R ¹ represents an alkyl group having a carbon number ranging from 1 to 10 and R ² represents halogen, OCF ₃ , CF ₃ or CN.

The method for preparing the compound I represented by Chemical Formula 1 can be prepared according to a known method, such as, but not limited to, using the following reaction formulas of Step 1 to Step 4: [Step 1] [Step 2] [Step 3] [Step 4] .

The liquid crystal medium of the present invention can further select other liquid crystal compounds according to actual needs. Preferably, the liquid crystal medium further comprises at least one compound II, which is represented by Chemical Formula 2: [Chemical Formula 2] In Chemical Formula 2, R ³ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 Alkenyloxy, one or more hydrogens of the alkyl, alkoxy, alkenyl or alkenyloxy may be optionally substituted by fluorine; B ¹ represents 1,4-cyclohexyl, 1,4-benzene base, or B ² and B ³ each represent 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4- Phenylene or 3-fluoro-1,4-phenylene; p represents 0 or 1; Z ¹ represents a single bond, − (CH ₂ ) ₂ −, −COO−, −CH ₂ O−, −OCO−, −CF ₂ O−, −OCF ₂ −, −C≡C−, or −CH = CH−; and R ⁴ represents halogen, OCF ₃ , OCHCF ₂ , OCF ₂ H, CF _3, or CN.

Preferably, the compound II is selected from a compound represented by Chemical Formula 2-1 or a compound represented by Chemical Formula 2-2: [Chemical Formula 2-1] [Chemical Formula 2-2] .

Preferably, in the chemical formulae 2-1 and 2-2, R ³ represents an alkyl group having a carbon number ranging from 1 to 10; B ² and B ³ each represent 1,4-cyclohexyl, 1,4-benzene Group, 3,5-difluoro-1,4-phenylene or 3-fluoro-1,4-phenylene; Z ¹ represents a single bond or −CF ₂ O−; R ⁴ represents fluorine, OCHCF ₂ or OCF ₂ H.

Preferably, the liquid crystal medium further comprises at least one compound III, which is represented by Chemical Formula 3: [Chemical Formula 3] In Chemical Formula 3, R ⁵ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 Alkenyloxy, one or more hydrogens of the alkyl, alkoxy, alkenyl or alkenyloxy may be optionally substituted by fluorine; C ¹ , C ² , C ³ and C ⁴ each represent 1,4- Cyclohexyl, 1,4-phenylene, 2,3-difluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,5-phenylbenzofuranyl, or 2 , 6-Extended 7,8-difluoro-1,3-benzodioxane; q, r and s each represent 0 or 1; Z ² , Z ³ and Z ⁴ each represent a single bond, − (CH ₂ ) ₂ −, −COO−, −CH ₂ O−, −OCO−, −CF ₂ O−, −OCF ₂ −, −C≡C−, or −CH = CH−; and R ⁶ represents halogen, OCF ₃ , CF ₃ , CN, alkyl with 1 to 10 carbons, alkoxy with 1 to 10 carbons, alkenyl with 2 to 10 carbons or alkenyl with 2 to 10 carbons One or more hydrogens in the alkyl, alkoxy, alkenyl, or alkenyloxy group may be optionally substituted with fluorine.

Preferably, the compound III is selected from a compound represented by Chemical Formula 3-1, a compound represented by Chemical Formula 3-2, a compound represented by Chemical Formula 3-3, a compound represented by Chemical Formula 3-4, or a compound represented by Chemical Formula 3-5 : [Chemical Formula 3-1] [Chemical Formula 3-2] [Chemical Formula 3-3] [Chemical Formula 3-4] [Chemical Formula 3-5] .

Preferably, in the chemical formulae 3-1 to 3-5, R ⁵ represents an alkyl group having a carbon number ranging from 1 to 10 or an alkenyl group having a carbon number ranging from 2 to 10; Z ² , Z ³ and Z ⁴ each represent Single bond or −C≡C−; R ⁶ represents fluorine, OCF ₃ , alkyl group having 1 to 10 carbon atoms, alkoxy group having 1 to 10 carbon atoms or alkenyl group having 2 to 10 carbon atoms .

Preferably, the liquid crystal medium further comprises at least one compound IV, which is represented by Chemical Formula 4: [Chemical Formula 4] In Chemical Formula 4, R ⁷ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 Alkenyloxy, one or more hydrogens of the alkyl, alkoxy, alkenyl or alkenyloxy are optionally substituted by fluorine; X ³ , X ⁴ , X ⁵ and X ⁶ each represent hydrogen or fluorine; D ¹ represents 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, or 3 -Fluoro-1,4-phenylene; and R ⁸ represents halogen, alkoxy having 1 to 10 carbons, alkenoxy having 2 to 10 carbons, OCHCF ₂ , OCF ₃ , CF ₃ or CN, one or more hydrogens of the alkoxy or alkenyloxy group are optionally substituted with fluorine.

Preferably, in the compound IV represented by Chemical Formula 4, R ⁷ represents an alkyl group having a carbon number ranging from 1 to 10; X ³ , X ⁴ , X ⁵ and X ⁶ each represent hydrogen; D ¹ represents 1,4- Phenylene; R ⁸ represents OCHCF ₂ .

When the liquid crystal medium includes at least one compound I, at least one compound II, at least one compound III, and at least one compound IV, preferably, the total content range of the compound I is calculated based on the total weight of the liquid crystal medium being 100 wt%. It is 1 to 30 wt%, the total content of the compound II ranges from 1 to 30 wt%, the total content of the compound III ranges from 40 to 90 wt%, and the total content of the compound IV ranges from 0 to 10 wt%. More preferably, based on the total weight of the liquid crystal medium being 100 wt%, the total content of the compound I ranges from 1 to 25 wt%, and the total content of the compound II ranges from 5 to 20 wt%. The content ranges from 50 to 90 wt% and the total content of the compound IV ranges from 0 to 5 wt%.

The display unit of the present invention includes the above-mentioned liquid crystal medium. The display unit of the present invention can be applied to various displays, such as, but not limited to, TN, STN, FFS, IPS, VA, PSA, and the like.

The present invention will be further described with reference to the following examples, but it should be understood that this example is for illustrative purposes only and should not be construed as a limitation on the implementation of the present invention.

The structures of the liquid crystal compounds in the following examples and comparative examples are represented by the codes in Table 1 below: [Table 1]

[ Test ] The following examples and comparative examples were selected for testing according to the following methods: 1. Clearing point temperature ( _Tni , ° C): Using a differential scanning calorimeter (DSC) system, the test liquid or liquid crystal The medium is placed on an aluminum pan and finely weighed from 0.5 to 10 mg. The phase change temperature is determined by the starting point of the endothermic peak and the exothermic peak of the liquid or liquid crystal medium due to the phase change. The phase change is expressed as follows: the crystalline phase is labeled C, the smectic phase is labeled S, the nematic phase is labeled N, and the liquid is labeled I. Among them, the phase transition temperature from the nematic phase to the liquid is the clearing point temperature (T _ni ). 2. Dielectric anisotropy (Δε): Put the test liquid or liquid crystal medium into the liquid crystal cell, and apply a voltage of 0 V to 20 V to the liquid crystal cell at a temperature of 25 ° C. The average dielectric constant measured in the axial direction is ε _‖ , the average dielectric constant measured perpendicular to the long axis of the liquid crystal molecules is ε _⊥ , and the dielectric anisotropy (Δε) = ε _‖- ε _⊥ . According to the Japanese Journal of Applied Physics , 53, p.010304, 2014, it can be known that the larger the ε _{⊥, the} greater the light transmission. 3. Rotary viscosity (γ1, mPa • S): Put the liquid to be measured or the liquid crystal medium into the liquid crystal cell, apply a voltage of 20 V to the liquid crystal cell at a temperature of 25 ° C, and add the dielectric anisotropy through the instrument (Δε) factor conversion, the rotational viscosity γ1 can be obtained. 4. K11 elastic constant ("slope spread", pN at 20 ° C): Put the liquid to be measured or the liquid crystal medium into the liquid crystal cell, and apply a voltage of 20 V to the liquid crystal cell at a temperature of 25 ° C. After adding the dielectric anisotropy (Δε) factor conversion to the instrument, K11 can be obtained. 5. K33 elastic constant ("bend", pN at 20 ° C): Put the liquid to be measured or the liquid crystal medium into the liquid crystal cell, and apply a voltage of 20 V to the liquid crystal cell at a temperature of 25 ° C. K33 can be obtained by adding dielectric anisotropy (Δε) factor to the instrument. 6. Refractive index anisotropy (Δn): An Abbe refractometer (manufacturer: ATAGO; model: DR-M2) with a polarizing plate mounted on an eyepiece is used to measure the liquid to be measured or the liquid crystal medium. First, wipe the surface of the main ridge of the Abbe refractometer in one direction, then drop a small amount of liquid to be measured on the main ridge, and then refract with a filter with a wavelength of 589 nm at a test temperature of 25 ° C. Measurement of rate anisotropy. When the polarization direction is parallel to the wiping direction, the measured refractive index is n _‖ ; when the polarization direction is perpendicular to the wiping direction, the measured refractive index is n _⊥ ; the refractive index anisotropy (Δn) = n _‖ -n _⊥ . 7. Low temperature storage (LTS, unit: day): Put 0.3 g of the test solution or liquid crystal medium into a 7 mL glass bottle, and place the glass bottle in a fixed temperature of -30 ° C to freeze In the cabinet, record the liquid crystal precipitation time, which is the number of days of low temperature storage. The longer the cold storage days, the better.

[ Preparation Examples 1 and 2] Compound I represented by Chemical Formula 1-2B The following description uses Preparation Example 1 as an example: 1. 4-propylphenol (3.3 g, 24 mmol), magnesium chloride (3.9 g, 36 mmol), paraformaldehyde (5 g, 165 mmol), and triethylamine (13.5 mL (9.3 mmol) and acetonitrile (60 mL) were placed in a 250 mL double-necked flask and mixed to obtain a reaction solution. This reaction solution was heated under reflux under nitrogen, and during the reaction, it was confirmed whether the reaction was complete with a thin film chromatograph (TLC). After 4 hours of reaction, the reaction was confirmed to be complete, and an aqueous hydrochloric acid solution (1N, 50 mL) was added to the reaction solution to obtain a mixed solution. Next, the mixed solution was repeatedly extracted three times with ethyl acetate, and the organic layer was collected. Anhydrous magnesium sulfate was added to the organic layer, followed by filtration and concentration under reduced pressure to obtain a crude product. The crude product was purified by column chromatography (eluent was a mixed solution of ethyl acetate and n-hexane, and the volume ratio of ethyl acetate to n-hexane was 1: 9), and finally 2-hydroxy-5-propyl was obtained -Benzaldehyde (3.2 g, yellow liquid). The aforementioned reaction process is as follows: (R ¹ = C ₃ H ₇ ) 2. Place sodium borohydride (0.9 g, 24 mmol) and methanol (30 mL) in a 250 mL double-necked flask and cool to 0 ° C. Then 2-hydroxy-5-propyl-benzaldehyde (2.0 g, 12 mmol) was slowly dropped into the double-necked flask, and after stirring for 1 hour, it was confirmed by TLC whether the reaction was complete. After confirming the completion of the reaction, an aqueous hydrochloric acid solution (1N, 25 mL) was added to the double-necked flask to obtain a mixed solution. The mixture was repeatedly extracted three times with ethyl acetate, and the organic layer was collected. Anhydrous magnesium sulfate was added to the organic layer, followed by filtration and concentration under reduced pressure to obtain a crude product. The crude product was purified by column chromatography (the extract was a mixed solution of ethyl acetate and n-hexane, and the volume ratio of ethyl acetate to n-hexane was 2: 8), and finally 2-hydroxymethyl-4- Propylphenol (1.7 g, white solid, SL1). The aforementioned reaction process is as follows: 3. Tetrakis (triphenylphosphine) palladium (0.34g, 3mol%), 4-bromo-3-fluoro-benzaldehyde (3.0g, 14.8mmol), 4-[(3 ', 4', 5'- Trifluorophenyl) -difluoromethoxy] -3,5-difluorophenylboronic acid (8.6g, 60mmol, the synthesis of this compound can refer to EP 1341742A1), potassium carbonate (6.1g, 44.4mmol), water ( 20 mL) and tetrahydrofuran (180 mL) were added to a double-necked round bottom flask and stirred to obtain a reaction solution. This reaction liquid was heated and refluxed, and it was confirmed by TLC that the reaction was complete during the reaction. After 24 hours of reaction, the reaction was confirmed to be complete, and water (100 mL) was added to the reaction solution to obtain a mixed solution. Next, the mixed solution was repeatedly extracted three times with ethyl acetate, and the organic layer was collected. Anhydrous magnesium sulfate was added to the organic layer, followed by filtration and concentration under reduced pressure to obtain a crude product. The crude product was purified by column chromatography (eluent: n-hexane) to obtain compound SR2 (5.8 g, white solid). The aforementioned reaction process is as follows: (R ² = F) 4. Add compound SR2 (1.0 g, 2.4 mmol), dichloromethane (30 mL), and trimethylchlorosilane (0.5 g, 4.8 mmol) to a 250 mL double-necked flask and perform at room temperature. stirring and mixing; Subsequently, the 2-hydroxymethyl-4-propyl phenol solution [via the 2-hydroxymethyl-4-propylphenol 1.2g (e.g. SL1, R ¹ is C ₃ H ₇₎ was dissolved in 10mL Obtained by dichloromethane] Slowly dripped into a double-necked flask, and after stirring for 0.5 hours, it was confirmed by TLC whether the reaction was complete. After confirming that the reaction is complete, water (25 mL) was added to the double-necked flask to obtain a mixed solution. The mixture was repeatedly extracted three times with dichloromethane, and the organic layer was collected. Anhydrous magnesium sulfate was added to the organic layer, followed by filtration and concentration under reduced pressure to obtain a crude product. The crude product was purified by column chromatography (the extract was a mixed solution of ethyl acetate and n-hexane, and the volume ratio of ethyl acetate to n-hexane was 1: 9), and finally the chemical formula 1-2B of Preparation Example 1 was obtained. Compound I shown (0.9 g, white solid, R ¹ is C ₃ H ₇ , R ² is F). The aforementioned reaction process is as follows: (R ¹ is C ₃ H ₇ , R ² is F, and is designated as “3SGUQUF” below) The molecular weight measurement of the compound of Preparation 1 was performed using a gas chromatograph tandem mass spectrometer (GC-MS), and the result was: m / z = 580.1362 [M] ⁺ . The spectrum measurement of the compound of Preparation 1 was performed by a nuclear magnetic resonance apparatus, and the results were: ¹ H-NMR (CDCl ₃ , 400MHz), d (ppm): 0.968 (3H, t, J = 7.2Hz), 1.637 (2H, m), 2.563 (2H, t, J = 7.6Hz), 5.025 (1H, d, J = 14.8Hz), 5.226 (1H, d, J = 14.8Hz), 6.871 (1H, s), 6.913 (2H, d, J = 8.4 Hz), 7.039 (3H, m), 7.250 (2H, d, J = 10.4), 7.531 (3H, m). The compound (R ¹ is C ₂ H ₅ and R ² is F) shown in Chemical Formula 1-2B in Preparation Example 2 is prepared in the same manner as in Preparation Example 1, and is also prepared according to the above reaction formulas; Preparation Example 2 and Preparation Example 1 The difference is that R ¹ in the reaction formula is C ₂ H ₅ , and it is marked as "2SGUQUF" below. A gas chromatograph tandem mass spectrometer (GC-MS) was used to measure the molecular weight of the compound of Preparation Example 2, and the result was: m / z = 580.1362 [M] ⁺ . The spectrum measurement of the compound of Preparation 2 was performed with a nuclear magnetic resonance instrument, and the results were: ¹ H-NMR (CDCl ₃ , 400MHz), d (ppm): 1.205 (3H, t, J = 7.2Hz), 2.580 (2H, q, J = 7.6Hz), 4.983 (1H, d, J = 14.8Hz), 5.188 (1H, d, J = 14.8Hz), 5.979 (1H, s), 6.849 (1H, s), 6.878 (1H, d, J = 8.4 Hz), 6.994 (3H, m), 7.208 (2H, J = 10.4 Hz), 7.472 (3H, m).

[ Preparation Examples 3 and 4] Compound I represented by Chemical Formula 1-2A The compound of Formula 1-2A (R ¹ is C ₃ H ₇ , R ² is F) in Preparation Example 3 is prepared in the same manner as in Preparation Example 1, and is also prepared according to the above reaction formulas; Preparation Example 3 and Preparation Example 1 The difference is that the SR2 compound in the reaction formula is substituted with the following SR1, and the preparation method of SR1 is as follows (the 4-bromo-3-fluoro-benzaldehyde in the SR2 production method is replaced with 4-bromo-benzaldehyde). Preparation Example 3 is designated as "3SPUQUF" below. A gas chromatograph tandem mass spectrometer (GC-MS) was used to measure the molecular weight of the compound of Preparation Example 3, and the result was: m / z = 562.1467 [M] ⁺ . The spectrum measurement of the compound of Preparation Example 3 was performed by a nuclear magnetic resonance apparatus, and the results were: ¹ H-NMR (CDCl ₃ , 400 MHz), d (ppm): 1.105 (3H, t, J = 7.2Hz), 1.645 (2H, m), 2.263 (2H, t, J = 7.6Hz), 5.103 (1H, d, J = 14.8Hz), 5.221 (1H, d, J = 14.8Hz), 6.156 (1H, s), 6.871 (1H, s), 6.892 (1H, d, J = 8.4Hz), 7.036 (3H, m), 7.178 (2H, J = 10Hz), 7.633 (2H, d, J = 10.4Hz), 7.724 (2H, d, J = 10.4Hz). The preparation method of the compound represented by Chemical Formula 1-2A in Preparation Example 4 (R ¹ is C ₂ H ₅ and R ² is F) is the same as that in Preparation Example 3; The difference between Preparation Example 4 and Preparation Example 3 is that: R ¹ is C ₂ H ₅ and is designated as "2SPUQUF" below. A gas chromatograph-tandem mass spectrometer (GC-MS) was used to measure the molecular weight of the compound of Preparation Example 4, and the result was: m / z = 548.1196 [M] ⁺ . The spectrum measurement of the compound of Preparation 4 was performed with a nuclear magnetic resonance instrument, and the results were: ¹ H-NMR (CDCl ₃ , 400 MHz), d (ppm): 1.207 (3H, t, J = 7.2 Hz), 2.285 (2H, q, J = 7.6Hz), 4.985 (1H, d, J = 14.8Hz), 5.193 (1H, d, J = 14.8Hz), 6.006 (1H, s), 6.849 (1H, s), 6.860 (1H, d, J = 8.4Hz), 7.015 (3H, m), 7.145 (2H, J = 10Hz), 7.612 (2H, d, J = 10.4Hz), 7.713 (2H, d, J = 10.4Hz).

[ Production Example 5] Compound I represented by Chemical Formula 1-2C The compound of Formula 1-2C (R ¹ is OC ₄ H ₉ and R ² is F) in Preparation Example 5 is prepared in the same manner as in Preparation Example 1, and is also prepared according to the above reaction formulas; Preparation Example 5 and Preparation Example 1 The difference is that the SL1 compound in the reaction formula is substituted with the following SL2, and the production method of SL2 is as follows (the 4-propylphenol in the SL1 production method is replaced with 2,3-difluoro-4-butoxyphenol). Finally, the compound of Preparation Example 5 is prepared by reacting the SL2 compound with the SR1 compound. The reaction process is as follows: Preparation Example 5 is designated as "4OSyPUQUF" below. A gas chromatograph tandem mass spectrometer (GC-MS) was used to measure the molecular weight of the compound of Preparation Example 5, and the result was: m / z = 628.1195 [M] ⁺ . The spectrum measurement of the compound of Preparation 5 was performed by a nuclear magnetic resonance instrument, and the results were: ¹ H-NMR (CDCl ₃ , 400 MHz), d (ppm): 1.104 (3H, t, J = 7.2 Hz), 1.514 (2H, m), 1.819 (2H, m), 4.003 (2H, t, J = 6.4Hz), 4.978 (1H, d, J = 14.4Hz), 5.170 (1H, d, J = 14.8Hz), 6.052 (1H, s), 6.427 (1H, d, J = 8.0Hz), 7.012 (2H, m), 7.257 (2H, J = 10Hz), 7.655 (2H, d, J = 10.4Hz), 7.751 (2H, d, J = 10.4Hz)

[ Examples 1 to 16] Preparation of liquid crystal media According to the composition and content of Table 2 below, compounds I, II, III and IV were selected and mixed to prepare the liquid crystal media of Examples 1 to 16. Next, the properties of the liquid crystal media of Examples 1 to 16 were tested according to the test method of paragraph [0027], and the results are summarized in Table 3.

[Table 2] [Continued Table 2] [Continued Table 2]

[table 3]

A composition content of Table 2 and Table 3 Properties of the test, the liquid-crystalline medium demonstrated in Example 1 to 16 have a high Δε and ε _⊥, lower [gamma] l, and T _ni, K11, K33, and meet the requirements of the industry have encountered Δn .

[ Comparative Examples 1 and 2] According to the composition and content of Table 4 below, Compound II and Compound III were respectively selected and mixed to prepare the liquid crystal media of Comparative Examples 1 and 2. Next, the properties of the liquid crystal media of Comparative Examples 1 and 2 were tested according to the test method of paragraph [0027]. The results are summarized in Tables 5 and 6, respectively. In Table 5, the liquid crystal media of Example 16 and Comparative Example 2 are compared; in Table 6, Example 1 and Comparative Example 1 are compared.

[Table 4]

[table 5]

From the results in Table 5, it can be found that Example 16 can exhibit higher Δε and ε _⊥ as it contains 13% by weight of compound I, as well as a longer period of low-temperature storage, indicating that the liquid crystal medium containing compound I will be used in subsequent liquid crystal displays. When it is a unit, it can effectively reduce the starting voltage and increase the penetration.

[TABLE 6]

In Table 6, Comparative Example 1 is composed of Compound II and Compound III, and Example 1 is composed of Compound I and Compound III. From the results of the property test, it can be known that the _Tni temperature, Δε, ε _、, K11 and K33 are both higher than Comparative Example 1, showing that the liquid crystal medium containing Compound I can more effectively reduce the start-up voltage and increase the penetration when it is subsequently applied to a liquid crystal display unit.

In summary, since the liquid crystal medium of the present invention contains the compound I shown in Chemical Formula 1 with a special structure design and high Δε and ε _⊥ , it can effectively reduce the startup voltage and increase the penetration when it is subsequently applied to a liquid crystal display unit. . , So it can indeed achieve the purpose of cost invention.

However, the above are only examples of the present invention. When the scope of implementation of the present invention cannot be limited in this way, any simple equivalent changes and modifications made in accordance with the scope of the patent application and the content of the patent specification of the present invention are still Within the scope of the invention patent.

Claims (10)

A liquid crystal medium including: at least one compound I is represented by Chemical Formula 1: [Chemical Formula 1] In Chemical Formula 1, R ¹ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 One or more hydrogens in the alkyl, alkoxy, alkenyl, or alkenyl group may be optionally substituted with fluorine; X ¹ and X ² each represent hydrogen or fluorine; A ¹ , A ² , A ³ and A ⁴ each represent 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene Phenyl or 3-fluoro-1,4-phenylene; n represents 0, 1, or 2, when n is 2, two A ² may be the same or different; m and o represent 0 or 1, and m + o≥1; and R ² represents halogen, OCF ₃ , CF ₃ or CN. The liquid crystal medium according to claim 1, wherein the compound I is selected from a compound represented by Chemical Formula 1-1, a compound represented by Chemical Formula 1-2, or a compound represented by Chemical Formula 1-3: [Chemical Formula 1-1] , [Chemical Formula 1-2] [Chemical Formula 1-3] . The liquid crystal medium according to claim 2, wherein the chemical formula 1-2 is selected from the group consisting of: , and . The liquid crystal medium according to claim 1, further comprising at least one compound II, which is represented by Chemical Formula 2: [Chemical Formula 2] In Chemical Formula 2, R ³ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 Alkenyloxy, one or more hydrogens of the alkyl, alkoxy, alkenyl or alkenyloxy may be optionally substituted by fluorine; B ¹ represents 1,4-cyclohexyl, 1,4-benzene base, or B ² and B ³ each represent 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4- Phenylene or 3-fluoro-1,4-phenylene; p represents 0 or 1; Z ¹ represents a single bond, − (CH ₂ ) ₂ −, −COO−, −CH ₂ O−, −OCO−, −CF ₂ O−, −OCF ₂ −, −C≡C−, or −CH = CH−; and R ⁴ represents halogen, OCF ₃ , OCF ₂ H, CF _3, or CN. The liquid crystal medium according to claim 4, wherein the compound II is selected from a compound represented by Chemical Formula 2-1 or a compound represented by Chemical Formula 2-2: [Chemical Formula 2-1] [Chemical Formula 2-2] . The liquid crystal medium according to claim 1 or 4, further comprising at least one compound III, which is represented by Chemical Formula 3: [Chemical Formula 3] In Chemical Formula 3, R ⁵ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 Alkenyloxy, one or more hydrogens of the alkyl, alkoxy, alkenyl or alkenyloxy may be optionally substituted by fluorine; C ¹ , C ² , C ³ and C ⁴ each represent 1,4- Cyclohexyl, 1,4-phenylene, 2,3-difluoro-1,4-phenylene, 3-fluoro-1,4-phenylene, 2,5-phenylbenzofuranyl, or 2 , 6-Extended 7,8-difluoro-1,3-benzodioxane; q, r and s each represent 0 or 1; Z ² , Z ³ and Z ⁴ each represent a single bond, − (CH ₂ ) ₂ −, −COO−, −CH ₂ O−, −OCO−, −CF ₂ O−, −OCF ₂ −, −C≡C−, or −CH = CH−; and R ⁶ represents halogen, OCF ₃ , CF ₃ , CN, alkyl with 1 to 10 carbons, alkoxy with 1 to 10 carbons, alkenyl with 2 to 10 carbons or alkenyl with 2 to 10 carbons One or more hydrogens in the alkyl, alkoxy, alkenyl, or alkenyloxy group may be optionally substituted with fluorine. The liquid crystal medium according to claim 6, wherein the compound III is selected from the group consisting of a compound represented by Chemical Formula 3-1, a compound represented by Chemical Formula 3-2, a compound represented by Chemical Formula 3-3, and a compound represented by Chemical Formula 3-4. Or a compound represented by Chemical Formula 3-5: [Chemical Formula 3-1] [Chemical Formula 3-2] [Chemical Formula 3-3] [Chemical Formula 3-4] [Chemical Formula 3-5] . The liquid crystal medium according to claim 1, further comprising at least one compound IV, which is represented by Chemical Formula 4: [Chemical Formula 4] In Chemical Formula 4, R ⁷ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 Alkenyloxy, one or more hydrogens of the alkyl, alkoxy, alkenyl or alkenyloxy are optionally substituted by fluorine; X ³ , X ⁴ , X ⁵ and X ⁶ each represent hydrogen or fluorine; D ¹ represents 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene, or 3 -Fluoro-1,4-phenylene; and R ⁸ represents halogen, alkoxy having 1 to 10 carbons, alkenoxy having 2 to 10 carbons, OCHCF ₂ , OCF ₃ , CF ₃ or CN, one or more hydrogens of the alkoxy or alkenyloxy group are optionally substituted with fluorine. A compound is shown by Chemical Formula 1: [Chemical Formula 1] In Chemical Formula 1, R ¹ represents an alkyl group having a carbon number range of 1 to 10, an alkoxy group having a carbon number range of 1 to 10, an alkenyl group having a carbon number range of 2 to 10 or a carbon number range of 2 to 10 One or more hydrogens in the alkyl, alkoxy, alkenyl, or alkenyl group may be optionally substituted with fluorine; X ¹ and X ² each represent hydrogen or fluorine; A ¹ , A ² , A ³ and A ⁴ each represent 1,4-cyclohexyl, 1,4-phenylene, 3,5-difluoro-1,4-phenylene, 2,3-difluoro-1,4-phenylene Phenyl or 3-fluoro-1,4-phenylene; n represents 0, 1, or 2, when n is 2, two A ² may be the same or different; m and o represent 0 or 1, and m + o≥1; and R ² represents halogen, OCF ₃ , CF ₃ or CN. A display unit includes a liquid crystal medium according to any one of claims 1 to 8.