CN103756687B - A kind of liquid-crystal composition and application thereof containing cyclopentyl and five fluorine propylene ether type monomer - Google Patents

Abstract

The present invention relates to a kind of liquid-crystal composition containing cyclopentyl and five fluorine propylene ether type monomer, comprise general formula (I) compound and logical formula II compound.The liquid-crystal composition excellent performance obtained by the present invention, have lower viscosity, high resistivity and voltage retention, high temperature resistance and ultraviolet superior performance, liquid-crystal composition of the present invention solves that the TFT LCD response speed that exists in prior art is fast not, electric charge conservation rate is not high enough, the problem of high temperature resistance ultraviolet poor performance.

Description

A liquid crystal composition containing cyclopentyl and pentafluoropropylene ether monomers and its application

technical field

The invention relates to a liquid crystal composition containing cyclopentyl and pentafluoropropylene ether monomers, belonging to the technical field of liquid crystal display.

Background technique

Liquid crystal display elements work by utilizing the optical anisotropy and dielectric anisotropy of the liquid crystal material itself, and have been widely used at room temperature. Using the different characteristics and working modes of liquid crystal materials, the device can be designed into various working modes. Among them, TN mode (twisted nematic mode), STN mode (super twisted nematic mode), SBE ( Super Twisted Birefringence), ECB (Electrically Controlled Birefringence), VA Mode (Vertical Alignment), IPS (In-Plane Switching), etc., and many other improved modes based on the above modes.

For liquid crystal displays, liquid crystal compounds with good chemical and thermal stability, good stability to electric field and electromagnetic radiation, appropriate optical anisotropy, fast response speed and low threshold voltage have no liquid crystal medium is in line with current needs. For liquid crystal displays with active matrix addressing, the liquid crystal medium should also have a high charge retention rate, as well as good light and thermal stability.

However, the properties of liquid crystal media are contradictory, and the existing liquid crystal media cannot have the above properties at the same time. Therefore, in the field of liquid crystal materials, there is a need for new liquid crystal compositions with improved properties. Especially for many types of applications, liquid-crystal compositions must have a suitable broad nematic phase range, suitable refractive index, dielectric anisotropy and storage stability at low temperatures.

The compound containing polyfluoroalkenyl ether end group structure involved in the present invention was first disclosed in Japanese Patent JP2003015547 of Japan Asahi Electric Chemical Co., Ltd., and this type of structural compound has higher dielectric anisotropy and lower rotational Viscosity, suitable for TFT liquid crystal display. Patents CN102924243, US2011089374, Liquid Crystals (1991), 10 (6), 875-879 and Molecular Crystals and Liquid Crystals (1990), 191, 237-246 disclose some liquid crystal compounds containing cyclopentyl groups. However, there is no literature report on the combination of cyclopentyl and pentafluoroallyloxy in the nematic liquid crystal compound and its application.

There is a need in the art to develop new cyclopentyl liquid crystal compounds with improved properties to adapt to the continuous development of current liquid crystal compositions.

Contents of the invention

The object of the present invention is to provide a liquid crystal composition, which has proper optical anisotropy and large dielectric anisotropy, fast response speed and good high temperature and ultraviolet performance. The liquid crystal composition can be suitable for AM components, so that the AM components have the characteristics of fast response speed, high charge retention rate and the like.

In order to achieve the above object, the present invention adopts the following technical solutions:

A liquid crystal composition containing cyclopentyl and pentafluoropropylene ether monomers, comprising a compound of general formula (I) and a compound of general formula (II), wherein the compound represented by general formula (I):

In the formula: R ₁ represents -H, an alkyl or alkoxy group with 1-8 carbon atoms; wherein, the H in the alkyl or alkoxy group can be substituted by halogen, and one or more -CH2- can be independently is replaced by -CH=CH-, or -O-, but the O atoms are not required to be directly connected to each other;

A ₁ , A ₂ , A ₃ , and A ₄ are the same or different, and each independently represents

A ₅ means

Z ₁ , Z ₂ , Z ₃ , Z ₄ , and Z ₅ are the same or different, each independently representing a carbon-carbon single bond, -CF ₂ O-, -CH ₂ O-, -CH ₂ CH ₂ -, -CH=CH -.

k, l, m, and n are the same or different, and each independently represents 0, 1, and 2, and k+l+m+n≦4.

The class II compound is one or more of the compounds with the following structures:

In formula II, R ₂ represents C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or C ₂ -C ₁₂ alkenyl; R ₃ represents C ₁ -C ₁₂ alkyl; o independently Represents 0, 1 or 2.

Preferably, the compound represented by general formula I is one or more of the following structural formulas I-A～I-O:

In the above formula, R ₁ represents -H, an alkyl or alkoxy group with 1-8 carbon atoms; wherein, H in the alkyl or alkoxy group can be substituted by halogen, and one or more -CH ₂ - can be Each is independently substituted by -CH=CH-, or -O-, but it is required that the O atoms are not directly connected to each other; L ₅ to L ₁₀ are independently F or H atoms.

More preferably, in the liquid crystal composition of the present invention, the compound represented by the general formula I is specifically one or more of the compounds represented by the following formulas I-A-1 to I-O-1:

In the above formula, R ₁ represents -H, an alkyl or alkoxy group with 1-8 carbon atoms; wherein, H in the alkyl or alkoxy group can be substituted by halogen, and one or more -CH ₂ - can be Each is independently substituted by -CH=CH-, or -O-, but it is required that the O atoms are not directly connected to each other.

Most preferably, in the liquid crystal composition of the present invention, the compound represented by general formula I is specifically one or more of the compounds represented by formulas I-1 to I-75:

The preparation method of the above-mentioned liquid crystal compound containing cyclopentyl and pentafluoroallyloxy comprises the following steps:

step 1): Metallization reaction with butyllithium, and then with react, produce

Step 2): Under the catalysis of p-TsOH, the dehydration reaction produces

Step 3): Under the catalysis of platinum carbon, it reacts with hydrogen to generate

Step 4): Carry out metallation reaction with butyllithium, and then react with B(OCH ₃ ) ₃ to generate

Step 5): Catalyzed, with react, produce

Step 6): Under the catalysis of palladium carbon, it reacts with hydrogen to form

Step 7): React with CF ₂ ═CFCF ₂ OSO ₂ F to generate the compound of the above general structure formula (I).

In the above steps 1) to 7), X ₁ in the structural formula represents H or Br, R, A ₁ , A ₂ , A ₃ , A ₄ , A ₅ , Z ₁ , Z ₂ , Z ₃ , Z ₄ The definitions of , Z ₅ , k, l, m, and n are the same as those in the general structural formula (I).

The synthetic route is as follows:

In step 1) described in the above method, , butyllithium and The molar ratio of feeding is 1:1.0-1.5:0.9-1.2, the reaction temperature is -50°C--90°C, and the reaction time is 2-5 hours.

In the step 2), The molar ratio of feeding to p-TsOH is 1:0.03-0.10, the reaction temperature is 100-150°C, and the reaction time is 5-10 hours.

In the step 3), The molar ratio of feeding to platinum carbon is 1:0.003-0.01, the reaction temperature is 20-50°C, and the reaction time is 4-10 hours.

In the step 4), , The molar ratio of butyl lithium to B(OCH ₃ ) ₃ is 1:1.0-1.5:1.2-2.0, the reaction temperature is -50°C--90°C, and the reaction time is 2-5 hours.

In the step 5), The molar ratio of feed to Pd(PPh ₃ ) ₄ is 1:1.0-1.3:0.002-0.01, the reaction temperature is 70-120°C, and the reaction time is 5-10 hours.

In the step 6), The molar ratio of feeding to palladium carbon is 1:0.003-0.01, the reaction temperature is 20-50°C, and the reaction time is 4-10 hours.

In the step 7), The feeding molar ratio of CF ₂ =CFCF ₂ OSO ₂ F is 1:1.1-2.5, the reaction temperature is 0-50°C, and the reaction time is 2-6 hours.

Preferably, in the preparation method of the present invention, in step 1),

Butyl Lithium and The molar ratio of feed is 1:1.5:1, the reaction temperature is -75°C to -85°C, and the reaction time is 3 hours.

In the step 2), The molar ratio of feeding to p-TsOH is 1:0.05, the reaction temperature is 125°C, and the reaction time is 8 hours.

In the step 3), The molar ratio of feeding to platinum carbon is 1:0.005, the reaction temperature is 25°C, and the reaction time is 5 hours.

In the step 4), 1. The molar ratio of butyl lithium to B(OCH ₃ ) ₃ is 1:1.5:1.7, the reaction temperature is -75°C to -85°C, and the reaction time is 3 hours.

In the step 5), The molar ratio of feed to Pd(PPh ₃ ) ₄ is 1:1.1:0.005, the reaction temperature is 80°C, and the reaction time is 8 hours.

In the step 6), The molar ratio of feed to palladium carbon is 1:0.005, the reaction temperature is 25°C, and the reaction time is 5 hours.

In the step 7), The molar ratio of feed to CF ₂ ═CFCF ₂ OSO ₂ F is 1:2, the reaction temperature is 20°C, and the reaction time is 3 hours.

Mentioned in the technical solution of the present invention CF ₂ ═CFCF ₂ SO ₃ F can be synthesized through open commercial channels or methods known in the literature itself, and the details are within the grasp of those skilled in the art, and the present invention is not particularly limited thereto.

The compound represented by general formula II provided by the present invention is preferably one or more of the compounds represented by formula II-1 to formula II-45:

In the liquid crystal composition of the present invention, the compound represented by general formula I is the primary component. This type of compound has strong polarity, appropriate optical anisotropy, and has a higher clearing point. The system has a good effect of lowering the threshold voltage, and at the same time, it also shows excellent performance when it is miscible with other compounds.

The compound represented by the general formula II is an essential class of compounds for the preparation of fast-response liquid crystal compositions. This type of compound has almost no polarity, and the structure of bicyclohexane makes it have extremely low viscosity and small optical anisotropy , plays an irreplaceable role in reducing the viscosity of the entire mixed system, and then plays a significant role in improving the response speed of the mixed crystal.

The above-mentioned liquid crystal composition containing cyclopentyl and pentafluoropropylene ether monomers includes the following components in weight percentage:

(1) 1-80% Class I compounds;

(2) 1-80% class II compounds;

(3) 0-50% of Class III compounds;

(4) 0-50% of Class IV compounds;

(5) 0-20% of V and VI compounds;

Among them, the sum of components (1) to (5) is 100%;

(6) Optically active components with a content of 0-0.5%; for the liquid crystal composition of the present invention, if used in IPS or FFS mode liquid crystal displays, the content of optically active components is 0%; if used in TN- In the TFT mode liquid crystal display, the function of adding optically active components is to twist the liquid crystal composition by 90° in the liquid crystal cell, so as not to cause under-twisting and affect the display effect, so its content is 0.05-0.5%, preferably 0.07-0.3 %.

The class III compound is one or more of the compounds of the following structures:

R ₄ and R ₅ independently represent C ₁ -C ₁₂ alkyl groups;

L ₁ and L ₂ independently represent H or F;

A ₆ means

p independently represents 0, 1 or 2.

The class IV compound is one or more of the compounds of the following structures:

R ₆ represents an alkyl group of C ₁ to C ₁₂ ;

L ₃ and L ₄ independently represent H or F;

X represents —F, —CF ₃ , —OCF ₃ , —OCHF ₂ , —CF=CF ₂ —, —CF ₂ —CF=CF ₂ or —CF=CF—CF ₃ ;

q stands for 0, 1 or 2;

A ₇ means

A ₈ means

The V and/or VI compounds are one or more of the compounds of the following structures:

R ₇ and R ₈ independently represent C ₁ -C ₁₂ alkyl groups;

r stands for 0, 1 or 2;

A ₉ means

A ₁₀ means

Preferably, the compound represented by the general formula III provided by the present invention is one or more of the following structural formulas III-A~III-E:

In the above formula, R ₄ and R ₅ independently represent a C ₁ -C ₁₂ alkyl group.

More preferably, in the liquid crystal composition of the present invention, the compound represented by the general formula III is specifically one or more of the compounds represented by the following formulas III-1 to III-54:

In the liquid crystal composition of the present invention, the compound represented by the general formula III has a larger optical anisotropy, a higher temperature range of the nematic phase, and excellent comprehensive performance. Adding such components in the mixed liquid crystal can effectively Improve optical anisotropy.

Preferably, the compound represented by general formula IV provided by the present invention is one or more of the compounds represented by formula IV-1 to formula IV-80:

In the liquid crystal composition of the present invention, the compound represented by the general formula IV has a relatively high dielectric constant, a moderate optical anisotropy, a relatively high nematic phase temperature range, and excellent comprehensive performance. Such components can effectively reduce the threshold voltage and stabilize the performance of the system.

Preferably, the liquid crystal composition containing cyclopentyl and pentafluoropropene ether compounds provided by the present invention includes the following components in weight percent:

(1) 5-70% of the compound represented by general formula I;

(2) 5-50% of the compound represented by general formula II;

(3) 0-20% of the compound represented by general formula III;

(4) 1-40% of the compound represented by general formula IV;

(5) 0-10% of compounds represented by general formula V and/or VI;

Among them, the sum of the above (1) to (5) is 100%.

More preferably, the liquid crystal composition provided by the present invention comprises the following components by weight percentage:

(1) 10-66% of the compound represented by general formula I;

(2) 10-45% of the compound represented by general formula II;

(3) 0-10% of the compound represented by general formula III;

(4) 3-30% of the compound represented by general formula IV;

(5) 0-5% of compounds represented by general formula V and/or VI;

Among them, the sum of the above (1) to (5) is 100%.

As one of the preferred modes of the present invention, the provided liquid crystal composition comprises the following components by weight percentage:

(1) 35-72% of the compound represented by general formula I;

(2) 21-45% of the compound represented by general formula II;

(3) 0-5% of the compound represented by general formula III;

(4) 3-30% of the compound represented by general formula IV;

(5) 0-5% of compounds represented by general formula V and/or VI;

Among them, the sum of the above (1) to (5) is 100%.

In addition, in order to improve the stability of the liquid crystal composition against heat and light, especially ultraviolet light, ultraviolet absorbers can also be added according to the situation, such as: benzotriazoles, benzophenones, triazines, benzoate esters ; Hindered amine light stabilizer; Hindered phenolic antioxidant.

The liquid crystal composition of the present invention can be prepared by a conventional method, such as mixing two or more liquid crystal compounds at high temperature and dissolving each other, that is, dissolving the liquid crystal compound in a solvent for the compound and mixing, and then The solvent is distilled off under low temperature; or the component with a smaller content is dissolved in the main component with a larger content at a higher temperature, or each component is dissolved in an organic solvent, and then the solutions are mixed and removed obtained after solvent. Wherein, the solvent used may be common organic solvents such as acetone, chloroform or methanol.

The liquid crystal composition of the present invention can be used in liquid crystal display devices, especially for various fast-response TFT displays, such as TN type, IPS type or FFS type TFT liquid crystal displays.

The liquid crystal composition obtained by the present invention has excellent performance, has low viscosity, high resistivity and voltage retention, and has excellent high temperature resistance and ultraviolet resistance. The liquid crystal composition of the present invention solves the problem of TFT liquid crystal existing in the prior art The display response speed is not fast enough, the charge retention rate is not high enough, and the high temperature and ultraviolet resistance is poor.

Detailed ways

The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

The optically active components of the present invention, S811, R811, S1011, R1011, S2011 and R2011 are all derived from Beijing Bayi Space-Time Liquid Crystal Technology Co., Ltd., and their structures are:

The liquid crystal composition of the present invention is prepared by a common method in the art—the thermal dissolution method. First, use a balance to weigh each liquid crystal compound by weight percentage. There is no specific requirement for the order of weighing and adding. Usually, the liquid crystal compound is weighed and mixed in order of melting point from high to low, and heated and stirred at 60-100°C to melt each component. uniform, then filtered, degassed, and finally packaged to obtain the target sample. In addition, the method disclosed in the patent CN101502767A can also be used to prepare uniform liquid crystals.

Unless otherwise stated, in this context, percentages are by weight and all temperatures are given in degrees Celsius. The following abbreviations are used in the examples:

The parameter characteristic that needs to measure in embodiment adopts following abbreviation:

Cp Clearing point (°C, nematic-isotropic phase transition temperature) VHR charge retention n Bulk viscosity (mm ² /s, 20°C) Δε Dielectric Anisotropy (25°C) Vth Threshold voltage = characteristic voltage at relative 90% contrast (V, 20°C,) Δn Optical anisotropy (20°C, 589nm) ION Ion concentration value (pc) τ τ _on +τ _off (response time, ms) SR Resistivity

All optical data are measured at 20°C unless otherwise stated.

In the following examples, the abbreviations of each structural unit are shown in Table 1.

Table 1 Abbreviations of structural units

For example: Nh-P-G-U-Q-U-X means

Example 1

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 2. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 2 embodiment 1

Example 2

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 3. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 3 embodiment 2

Example 3

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 4. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 4 embodiment 3

Example 4

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 5. The cyclohexyl groups in all the following structural formulas are in trans configuration:

Proportioning and performance parameters of the liquid crystal composition of table 5 embodiment 4

Example 5

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 6. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 6 embodiment 5

Example 6

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 7. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 7 embodiment 6

Example 7

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 8. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 8 embodiment 7

Example 8

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition by the method described in the present invention. The specific ratio is shown in Table 9. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 9 embodiment 8

Example 9

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition by the method described in the present invention. The specific ratio is shown in Table 10. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 10 embodiment 9

Example 10

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition according to the method described in the present invention. The specific ratio is shown in Table 11. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 11 embodiment 10

Example 11

Take the liquid crystal compound in the following weight percentages and prepare the liquid crystal composition by the method described in the present invention. The specific ratio is shown in Table 12. The cyclohexyl groups in all the following structural formulas are in trans configuration:

The proportioning and performance parameter of the liquid crystal composition of table 12 embodiment 11

Although the present invention has been described in detail with general descriptions and specific embodiments above, it is obvious to those skilled in the art that some modifications or improvements can be made on the basis of the present invention. Therefore, the modifications or improvements made on the basis of not departing from the spirit of the present invention all belong to the protection scope of the present invention.

Claims (9)

1. A liquid crystal composition containing cyclopentyl and pentafluoropropylene ether monomers, characterized in that it comprises the following components in percentage by weight: (1) 35-72% of class I compounds; (2) 21-45% of class II compounds; (3) 0-5% of Class III compounds; (4) 3 to 30% of Class IV compounds; (5) 0-5% of V and VI compounds; Wherein, the sum of components (1) to (5) is 100%; Wherein, the class I compound is one or more of the compounds of the following structures: In the formula: R ₁ represents -H, an alkyl or alkoxy group with 1-8 carbon atoms; wherein, H in the alkyl or alkoxy group can be substituted by halogen, and one or more -CH ₂ - can be individually Independently substituted by -CH=CH-, or -O-, but the O atoms are not required to be directly connected to each other; A ₁ , A ₂ , A ₃ , and A ₄ are the same or different, and each independently represents A ₅ means Z ₁ represents a carbon-carbon single bond, -CH ₂ CH ₂ -; Z ₂ , Z ₃ , Z ₄ represent carbon-carbon single bonds; Z ₅ represents a carbon-carbon single bond, -CF ₂ O-; k and l independently represent 1, m represents 0 or 1, and n represents 0; The class II compound is one or more of the compounds with the following structures: In formula II, R ₂ represents C ₁ -C ₁₂ alkyl, C ₁ -C ₁₂ alkoxy or C ₂ -C ₁₂ alkenyl; R ₃ represents C ₁ -C ₁₂ alkyl; o represents 0 ,1; The class III compound is one or more of the compounds of the following structures: R ₄ and R ₅ independently represent C ₁ -C ₁₂ alkyl groups; L ₁ and L ₂ independently represent H or F; A ₆ means p stands for 0, 1 or 2; The class IV compound is one or more of the compounds of the following structures: R ₆ represents an alkyl group of C ₁ to C ₁₂ ; L ₃ , L ₄ , X represent F; q stands for 0, 1 or 2; A ₇ and A ₈ represent The V and/or VI compounds are one or more of the compounds of the following structures: R ₇ and R ₈ independently represent C ₁ -C ₁₂ alkyl groups; r stands for 0, 1 or 2; A ₉ and A ₁₀ indicate 2. The liquid crystal composition according to claim 1, wherein the type I compound is one or more of the following structural formulas I-A～I-E: In the above formula, R ₁ represents -H, an alkyl or alkoxy group with 1-8 carbon atoms; wherein, H in the alkyl or alkoxy group can be substituted by halogen, and one or more -CH ₂ - can be Each is independently substituted by -CH═CH-, or -O-, but the O atoms are not required to be directly connected to each other; L ₅ to L ₁₀ are independently F or H atoms. 3. The liquid crystal composition according to claim 1, wherein the type II compound is specifically one or more of the compounds represented by the following formulas I-A-1 to I-E-3: In the above formula, R ₁ represents -H, an alkyl or alkoxy group with 1-8 carbon atoms; wherein, H in the alkyl or alkoxy group can be substituted by halogen, and one or more -CH ₂ - can be Each is independently substituted by -CH=CH-, or -O-, but it is required that the O atoms are not directly connected to each other. 4. The liquid crystal composition according to claim 1, wherein the type I compound is specifically one or more of the compounds represented by formulas I-1 to I-45: 5. The liquid crystal composition according to claim 1, wherein the type II compound is one or more of the compounds represented by formula II-1 to formula II-45: 6 . The liquid crystal composition according to claim 1 , wherein the liquid crystal composition further comprises an optically active component, the content of which is 0.05-0.5% of the sum of components (1)-(5). 7. The liquid crystal composition according to claim 1, further comprising an ultraviolet absorber. 8. The application of the liquid crystal composition according to any one of claims 1-7 in a liquid crystal display device. 9. The application according to claim 8, wherein the liquid crystal display device is a TN type, IPS type or FFS type TFT liquid crystal display.