JP2015129278A - Liquid crystal composition and liquid crystal display - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid crystal composition and a liquid crystal display which have good cold resistance.SOLUTION: A liquid crystal composition contains a component represented by general formula (I), a component represented by general formula (II), and a third component whose content in the liquid crystal components is 10 wt.% or more. [Rand Rare H, alkyl or alkenyl; Ato Aare cyclohexylene, phenylene or the like; Zto Zare each a single bond, -CH=CH-, -C≡C-, -COO-, -OCO-, -CFO- or -OCF-; Xis -H, -F, -Cl, alkyl, or alkoxyl; m, n, o and p are each 0 or 1.]

Description

  The present invention relates to a liquid crystal composition, and particularly to a liquid crystal composition having good low-temperature resistance (low temperature storage) and a liquid crystal display device containing the liquid crystal composition.

  The liquid crystal display has advantages such as light weight, power saving, non-radiation and full-color display, and is thus already the most universal display product.

  In recent years, liquid crystal displays are passive, such as twisted nematic (TN) and super twisted nematic (STN), according to the continuous improvement of technology and the demand for high resolution, high reaction speed and high image quality. The driving display system has been developed into an active matrix liquid crystal display having a thin film transistor (TFT). The development and breakthrough of liquid crystal display systems such as in-plane switching (IPS) and vertical alignment (VA) in accordance with the demands of wide viewing angle technology are quite important for future panel applications and development It has become.

  As for the liquid crystal composition, a high dielectric anisotropy (Dε) is required to reduce the threshold voltage (Vth) of the liquid crystal display device; in order to increase the response speed, Low rotational viscosity (γ1) is required; high optical anisotropy (Dn) is required to increase contrast; high clearing point to adapt to use in various environments Temperature (Tni) is required. In order to meet these requirements, various studies on liquid crystal compositions have already been conducted, but satisfying certain properties often involves sacrifice of other properties, and thus liquid crystal that can satisfy the requirements of each direction. A composition has not yet been obtained.

  The present invention provides a liquid crystal composition, employs the liquid crystal composition to produce a liquid crystal display device, and provides the liquid crystal display device with good efficacy.

The liquid crystal composition of the present invention includes a component represented by the general formula (I), a component represented by the general formula (II), and a component represented by the general formula (III) having a content of more than 10% by weight. .
R ₁ , R ₂ , R ₃ and R ₄ are each —H, C ₁ -C ₁₅ alkyl group or C ₂ -C ₁₅ alkenyl group, and —CH ₂ — in the alkyl group or alkenyl group. Can be substituted with -O-, -CO-, -COO- or -OCO-, but the heteroatoms are not directly connected to each other;
A ₁ , A ₂ , A ₃ and A ₄ are groups of 1,4-phenylene, 1,4-cyclohexylene, indan-2,5-diyl and tetrahydropyran-2,5-diyl groups, respectively. Wherein hydrogen on 1,4-phenylene, 1,4-cyclohexylene and indan-2,5-diyl can be unsubstituted or substituted with a fluorine atom, and A ₁ , A ₂ , At least one of A ₃ and A ₄ is indan-2,5-diyl;
A ₅ , A ₆ , A ₇ , A ₈ and A ₉ are each selected from the group consisting of 1,4-phenylene, 1,4-cyclohexylene and tetrahydropyran-2,5-diyl groups, of which , 1,4-phenylene, 1,4-cyclohexylene and hydrogen on indan-2,5-diyl can be unsubstituted or substituted with fluorine atoms;
m, n, o and p are each 0 or 1 and m + n + o + p>2;
Z ₁ , Z ₂ , Z ₃ , Z ₄ , Z ₅ and Z ₆ are each a single bond, —CH═CH—, —C≡C—, —COO—, —OCO—, —CF ₂ O— or — OCF ₂ —, in which —CH═CH— hydrogen can be replaced by a fluorine atom;
X ₁ is -H, -F, -Cl, an unsubstituted C ₁ -C ₂₀ alkyl group, a halogen-substituted C ₁ -C ₂₀ alkyl group, or an unsubstituted C ₁ -C ₂₀ Or a C ₁ -C ₂₀ alkoxyl group substituted with a halogen. And —CH ₂ — in X ₁ is —O—, —S—, —CH═CH—, —C≡C—, —CF═CF—, —CH═CF—, —CF═CH—, — It can be substituted with COO- or -OCO-, but the heteroatoms are not directly connected to each other.

In the embodiment of the present invention, the component represented by the general formula (II) includes a component represented by the general formula (II-A) and a component represented by the general formula (II-B).
X ₂ is -H, -F, -Cl, unsubstituted C ₁ -C ₂₀ alkyl group, halogen substituted C ₁ -C ₂₀ alkyl group, unsubstituted C ₁ -C ₂₀ Or a C ₁ -C ₂₀ alkoxyl group substituted with halogen, but X ₂ does not include —OCF ₃ ; —CH ₂ — in X ₂ is —O—, —S—, -CH = CH-, -C≡C-, -CF = CF-, -CH = CF-, -CF = CH-, -COO- or -OCO- can be substituted, but a heteroatom Are not directly connected to each other.

  In the embodiment of the present invention, the component represented by the general formula (II-A) accounts for 4 to 60% by weight in the liquid crystal composition, preferably 12 to 60% by weight, and more preferably 25 to 55% by weight. The component represented by formula (II-B) accounts for 2 to 45% by weight, preferably 2 to 30% by weight, and more preferably 8 to 25% by weight in the liquid crystal composition.

  In the embodiment of the present invention, the component represented by the general formula (I) accounts for 1 to 30% by weight in the liquid crystal composition, preferably 1 to 25% by weight, and more preferably 4 to The component represented by the general formula (II) occupies 15% by weight, occupies 5 to 70% by weight in the liquid crystal composition, preferably 15 to 70% by weight, and more preferably 30 to 70% by weight. The component represented by the general formula (III) accounts for 15% to 70% by weight in the liquid crystal composition, preferably 15 to 60% by weight, and more preferably 16 to 41% by weight. Occupies%.

In an embodiment of the invention, p is not equal to 0 and A ₁ includes indan-2,5-diyl.

In an embodiment of the present invention, at least one of A ₁ , A ₂ , A ₃ , A ₄ , A ₅ , A ₆ , A ₇ , A ₈ and A ₉ is a group represented by formula IV) is there.

In the embodiment of the present invention, at least one of A ₅ , A ₆ and A ₇ is a group represented by the formula (V).

  In the embodiment of the present invention, m + n + o + p ≦ 4.

  The liquid crystal display element of the present invention includes any one of the liquid crystal compositions in the embodiment.

  Based on the above, the present invention provides a liquid crystal composition, which has good low-temperature storage stability, high Tni, high Dn, and high De, employs the liquid crystal composition to produce a liquid crystal display device, The display element can have characteristics such as power saving and high contrast, and can be applied to use in an outdoor environment.

  In order to make the above features and advantages of the present invention clearer and easier to understand, details will be described in the following embodiments.

  In the text, the range indicated by “from a certain numerical value to another numerical value” is a summary display method that avoids listing all numerical values in the range one by one in the specification. The description of a range is equivalent to disclosing any numerical value within the numerical range and a relatively small numerical range defined by any numerical value within the numerical range. Equivalent to specifying the arbitrary numerical value and the relatively small numerical range. For example, if the range of “the content is 10 to 80%” is described, it is equivalent to the disclosure of the range of “the content is 20% to 40%”, and other numerical values in the specification. Whether or not listed.

  In the text, a group can represent a substituted or unsubstituted group unless it is specifically stated whether the group has undergone substitution. For example, an “alkyl group” can represent a substituted or unsubstituted group.

  In the text, sometimes a skeleton formula represents the structure of a compound, and this notation can omit carbon atoms, hydrogen atoms and carbon-hydrogen bonds, and of course, atoms or When the atomic group is clearly depicted, the figure shown is the standard.

The liquid crystal composition presented by the first embodiment of the present invention includes a first component represented by general formula (I), a second component represented by general formula (II), and general formula (III). A third component represented by

R ₁ , R ₂ , R ₃ and R ₄ are each an —H, C ₁ -C ₁₅ alkyl group or a C ₂ -C ₁₅ alkenyl group, preferably —H, C ₁ -C ₁₀ alkyl Or a C ₁ -C ₁₀ alkenyl group, and —CH ₂ — in the alkyl group or alkenyl group can be substituted with —O—, —CO—, —COO— or —OCO—. However, the heteroatoms are not directly connected to each other.

A ₁ , A ₂ , A ₃ and A ₄ are groups of 1,4-phenylene, 1,4-cyclohexylene, indan-2,5-diyl and tetrahydropyran-2,5-diyl groups, respectively. Wherein hydrogen on 1,4-phenylene, 1,4-cyclohexylene and indan-2,5-diyl can be unsubstituted or substituted with a fluorine atom, and A ₁ , A ₂ , At least one of A ₃ and A ₄ is indan-2,5-diyl.

_{A 5, A 6, A 7} , A 8 and A ₉ are each 1,4-phenylene, 1,4-cyclohexylene and tetrahydropyran-2,5-diyl group is selected from the group group that composition, of which , 1,4-phenylene, 1,4-cyclohexylene and hydrogen on indan-2,5-diyl can be unsubstituted or substituted with fluorine atoms.

  m, n, o, and p are each 0 or 1, and m + n + o + p> 2.

Z ₁ , Z ₂ , Z ₃ , Z ₄ , Z ₅ and Z ₆ are each a single bond, —CH═CH—, —C≡C—, —COO—, —OCO—, —CF ₂ O— or — OCF ₂ —, wherein —CH═CH— hydrogen can be replaced by a fluorine atom.

X ₁ is —H, —F, —Cl, unsubstituted C ₁ -C ₂₀ alkyl group, halogen substituted C ₁ -C ₂₀ alkyl group, unsubstituted C ₁ -C ₂₀ An alkoxyl group or a C ₁ -C ₂₀ alkoxyl group substituted with a halogen, in which the alkyl group or the alkoxyl group preferably has 1 to 10 carbon atoms; —CH ₂ — in X ₁ is -O-, -S-, -CH = CH-, -C≡C-, -CF = CF-, -CH = CF-, -CF = CH-, -COO- or -OCO- However, the heteroatoms are not directly connected to each other.

The sum of m, n, o, and p is greater than 2, and at least one of A ₁ to A ₄ is indan-2,5-diyl (this is a bicyclic compound whose structure is <Experimental>"RI" in the part can be referred to). Therefore, the first component represented by the formula (I) has a plurality of opposing ring numbers (for example, 4 or more), which may cause the liquid crystal composition to have high De, high Dn, and high Tni. In addition, the liquid crystal display element including the liquid crystal composition can have power saving, high contrast, and characteristics suitable for outdoor use. In addition, in general, high De, high Dn, high Tni, and excellent low-temperature storage properties are often difficult to achieve, but the liquid crystal composition contains the first to third components. Sometimes, De, Dn and Tni can not only meet the application requirements but also have very good low temperature storage. These features are proved by experiments below.

In embodiments, p is not equal to 0 and A ₁ includes indan-2,5-diyl. In other words, indan-2,5-diyl, and the first component, located on the opposite other end to -OCF _3,. More specifically, in the examples, p is equal to 1, A ₁ is indan-2,5-diyl, and A ₂ , A ₃ and A ₄ include indan-2,5-diyl. It does not have to be.

  In the embodiment, the component represented by the general formula (I) accounts for 1 to 30% by weight in the liquid crystal composition, preferably 1 to 25% by weight, and more preferably 4 to 15% by weight. The component represented by the general formula (II) accounts for 5 to 70% by weight, preferably 15 to 70% by weight, more preferably 30 to 70% by weight in the liquid crystal composition. The component represented by the general formula (III) occupies 15 to 70% by weight, preferably 15 to 60% by weight, and more preferably 16 to 41% by weight in the liquid crystal composition. .

In an embodiment of the present invention, at least one of A ₁ , A ₂ , A ₃ , A ₄ , A ₅ , A ₆ , A ₇ , A ₈ and A ₉ is a group represented by formula IV) is there.
More specifically, at least one of A ₅ , A ₆ and A ₇ is a group represented by the formula (V).

Whether A ₅ , A ₆ and A ₇ contain the structure of the above formula (V) or not may affect the dielectric anisotropy of the liquid crystal monomer, which may be positive type liquid crystal or negative type Regardless of whether or not the negative liquid crystal monomer is contained in the liquid crystal composition, if the liquid crystal composition contains the first to third components at the same time, all of them have low-temperature storage stability. Excellent effects can be achieved.

In the embodiment of the present invention, the component represented by the general formula (II) includes a component represented by the general formula (II-A) and a component represented by the general formula (II-B).

R ₂ , A ₅ , A ₆ , A ₇ , Z ₄ and Z ₅ are the same as described in the preceding sentence.

X ₂ is —H, —F, —Cl, unsubstituted C ₁ -C ₂₀ alkyl group, halogen substituted C ₁ -C ₂₀ alkyl group, unsubstituted C ₁ -C ₂₀ An alkoxyl group or a C ₁ -C ₂₀ alkoxyl group substituted with a halogen, X ₂ does not include —OCF ₃ , and the number of carbon atoms of the alkyl group and the alkoxyl group is preferably 1 to 10; -CH _2-in X ₂ is -O-, -S-, -CH = CH-, -C≡C-, -CF = CF-, -CH = CF-, -CF = CH- , -COO- or -OCO-, but the heteroatoms are not directly connected to each other. In other words, components of the general formula (II), the terminal can be contained at the same time a component containing no -OCF ₃ into components and terminal is -OCF _3.

  In the embodiment, the component represented by the general formula (II-A) accounts for 4 to 60% by weight, preferably 12 to 60% by weight, more preferably 25 to 55% by weight in the liquid crystal composition; The component represented by (II-B) accounts for 2 to 45% by weight, preferably 2 to 30% by weight, and more preferably 8 to 25% by weight in the liquid crystal composition.

  Regarding the method of synthesizing the first component, for example, Taiwanese Patent No. 9914-3515, filed on December 13, 2010 and published on June 1, 2012, with the name “liquid crystal compound and liquid crystal mixture”. The draft of the application can be referred to, and the entire contents of the draft are incorporated by reference in the draft of the present application and can be used as a basis for correcting and deciphering the draft of the present application. Is a liquid crystal compound known in the art, and its synthesis method will not be described in detail here.

Another embodiment of the present invention presents a liquid crystal display element, and the feature of the liquid crystal display element is that it includes any one kind of liquid crystal composition in the embodiment. In addition to the liquid crystal composition that can contain components of known liquid crystal display elements, such as a substrate, a polarizing sheet, a color filter, or an alignment film, the manufacturing method and components of this liquid crystal display element include It can be arbitrarily selected from the techniques of learning, and therefore details are not described here.
<Experiment>

  The present invention will be described more specifically with reference to the following examples. Examples have been described below, but the materials used, the amounts and ratios thereof, the processing details, the flow of processing, and the like can be appropriately changed under conditions that do not exceed the scope of the present invention. Therefore, the present invention should not be interpreted as being restrictive based on the examples described below.

The liquid crystal compositions of the comparative examples and the examples each include several tens of kinds of liquid crystal compounds, and in order to simplify the display, in the following, symbols are combined to represent different liquid crystal compounds, of which each symbol is Represents a structural unit of

In the symbol “V1”, the number “1” represents a methyl group, and similarly, the number shown in a normal font represents an alkyl group having the same number of carbon atoms. For example, 3RIUQU-OCF ₃ represents a compound whose structure is
3CCP1 represents a compound having the structure:

  Various liquid crystal compounds are mixed at the ratio (% by weight) shown in Table 1, thereby preparing the liquid crystal compositions of Comparative Examples 1 to 3 and the liquid crystal compositions of Examples 1 to 14. In Table 1, “C-1” to “C-4” represent Comparative Examples 1 to 4, respectively; “E-01” to “E-15” represent Examples 1 to 15, respectively. .

  In Table 1 and Table 1 on the next page (Continued 1), Applicant represents the first component (represented by formula (I)), second component (represented by formula (II-A) or formula (II-B)) And the third component (represented by formula (III)) are classified and clearly classified. The components described in Table 1 (continued) are other compounds contained in the liquid crystal composition.

  In addition to the above properties, Table 2 also shows the total contents of the first component, the second component, and the third component in each example in order to concentrate and compare the liquid crystal compositions of Examples and Comparative Examples. Referring to Table 2, if the liquid crystal composition does not contain the first component represented by formula (I) (Comparative Example 1 and Comparative Example 4), the liquid crystal can be stored within 3 days of storage at -30 ° C. Begins to precipitate. Example 10 and Comparative Example 4 having almost the same components are observed, and the comparison can be found particularly clearly. At the same time, if the liquid crystal composition does not contain the second component (Comparative Example 2) represented by the general formula (II-A) or the general formula (II-B), or simultaneously contains the first to third components Even so, the content of the third component is insufficient (Comparative Example 3), and the low-temperature storage stability is different compared to all Examples.

  In addition, each of the second components of Examples 1 and 2 is a single composition of the compound represented by the general formula (II-A) and the compound represented by the general formula (II-B), which is stored at a low temperature. The comparative examples 1 to 4 are excellent, and the compounds of the general formula (II-A) and the general formula (II-B) are simultaneously contained in Examples 3 to 15, and the low-temperature storage stability is further excellent. ing.

  In summary, the present invention presents a liquid crystal composition containing a specific first component, second component and third component. When the liquid crystal composition contains these components, it has good low temperature storage, high Tni, high Dn and high De. By using the liquid crystal composition to produce a liquid crystal display element, it can have characteristics such as power saving and high contrast, and is suitable for use in an outdoor environment.

  The present invention provides a liquid crystal composition, which has good low-temperature storage stability, high Tni, high Dn, and high De, employs the liquid crystal composition to produce a liquid crystal display device, and saves the liquid crystal display device. It can have characteristics such as electric power and high contrast and can be applied to use in an outdoor environment.

Although the embodiments of the present invention have been disclosed as described above, the present invention is not limited thereto. Those skilled in the art can make various modifications and changes without departing from the spirit and scope of the present invention. Therefore, the protection scope of the present invention is based on the contents specified in the following claims. .

Claims (10)

A liquid crystal composition comprising a component represented by the general formula (I), a component represented by the general formula (II), and a component represented by the general formula (III) whose content is greater than 10% by weight in the liquid crystal composition .
R ₁ , R ₂ , R ₃ and R ₄ are each —H, C ₁ -C ₁₅ alkyl group or C ₂ -C ₁₅ alkenyl group, and —CH ₂ — in the alkyl group or alkenyl group. Can be substituted with -O-, -CO-, -COO- or -OCO-, but the heteroatoms are not directly connected to each other,
A ₁ , A ₂ , A ₃ and A ₄ are groups of 1,4-phenylene, 1,4-cyclohexylene, indan-2,5-diyl and tetrahydropyran-2,5-diyl groups, respectively. Wherein hydrogen on 1,4-phenylene, 1,4-cyclohexylene and indan-2,5-diyl can be unsubstituted or substituted with a fluorine atom, and A ₁ , A ₂ , At least one of A ₃ and A ₄ is indan-2,5-diyl;
A ₅ , A ₆ , A ₇ , A ₈ and A ₉ are each selected from the group consisting of 1,4-phenylene, 1,4-cyclohexylene and tetrahydropyran-2,5-diyl groups, of which , 1,4-phenylene, 1,4-cyclohexylene and hydrogen on indan-2,5-diyl can be unsubstituted or substituted with fluorine atoms;
m, n, o and p are each 0 or 1, and m + n + o + p> 2,
Z ₁ , Z ₂ , Z ₃ , Z ₄ , Z ₅ and Z ₆ are each a single bond, —CH═CH—, —C≡C—, —COO—, —OCO—, —CF ₂ O— or — OCF _2- , of which -CH = CH- can be replaced by a fluorine atom,
X ₁ is -H, -F, -Cl, an unsubstituted C ₁ -C ₂₀ alkyl group, a halogen-substituted C ₁ -C ₂₀ alkyl group, or an unsubstituted C ₁ -C ₂₀ Or a C ₁ -C ₂₀ alkoxyl group substituted with halogen, and —CH ₂ — in X ₁ is —O—, —S—, —CH═CH—, —C≡C— , -CF = CF-, -CH = CF-, -CF = CH-, -COO- or -OCO-, but the heteroatoms are not directly connected to each other. The liquid crystal composition according to claim 1, wherein the component represented by the general formula (II) includes a component represented by the general formula (II-A) and a component represented by the general formula (II-B).
X ₂ is —H, —F, —Cl, unsubstituted C ₁ -C ₂₀ alkyl group, halogen substituted C ₁ -C ₂₀ alkyl group, unsubstituted C ₁ -C ₂₀ An alkoxyl group or a C ₁ -C ₂₀ alkoxyl group substituted with a halogen, but X ₂ does not include —OCF _3, and —CH ₂ — in X ₂ is —O—, —S—, — CH = CH-, -C≡C-, -CF = CF-, -CH = CF-, -CF = CH-, -COO- or -OCO- can be substituted, but the heteroatom is Are not directly connected to each other.   The component represented by the general formula (II-A) accounts for 4 to 60% by weight in the liquid crystal composition, and the component represented by the general formula (II-B) is 2 to 45% by weight in the liquid crystal composition. The liquid crystal composition according to claim 2, which occupies%.   The component represented by the general formula (II-A) accounts for 12 to 60% by weight in the liquid crystal composition, and the component represented by the general formula (II-B) is 2 to 30% by weight in the liquid crystal composition. The liquid crystal composition according to claim 2 or 3 occupying%.   The component represented by the general formula (I) occupies 1 to 30% by weight in the liquid crystal composition, the component represented by the general formula (II) occupies 5 to 70% by weight in the liquid crystal composition, The liquid crystal composition according to claim 1, wherein the component represented by the general formula (III) accounts for 15 to 70% by weight in the liquid crystal composition.   The component represented by the general formula (I) accounts for 1 to 25% by weight in the liquid crystal composition, the component represented by the general formula (II) accounts for 15 to 70% by weight in the liquid crystal composition, 6. The liquid crystal composition according to claim 5, wherein the component represented by the general formula (III) accounts for 15 to 60% by weight in the liquid crystal composition. 7. The liquid crystal composition according to claim ₁ , wherein p is not equal to 0 and A ₁ contains indan-2,5-diyl. At least one of A ₁ , A ₂ , A ₃ , A ₄ , A ₅ , A ₆ , A ₇ , A ₈ and A ₉ is a group represented by the formula (IV). The liquid crystal composition according to any one of the above.
9. The liquid crystal composition according to claim 1, wherein at least one of A ₅ , A ₆ and A ₇ is a group represented by the formula (V).
The liquid crystal display element containing the liquid-crystal composition as described in any one of Claims 1-9.