Compositions – Liquid crystal compositions – Containing nonsteryl liquid crystalline compound of...
Reexamination Certificate
1997-12-08
2001-01-16
Kelly, C. H. (Department: 1756)
Compositions
Liquid crystal compositions
Containing nonsteryl liquid crystalline compound of...
C252S299660, C252S299610, C568S671000, C570S144000
Reexamination Certificate
active
06174456
ABSTRACT:
TECHNICAL FIELD
The present invention relates to a liquid crystalline compound and a liquid crystal composition, more particularly, it relates to a new liquid crystalline compound having substituted alkyl groups, a liquid crystal composition containing the liquid crystalline compound, and a liquid crystal display device constituted by using the liquid crystal composition.
BACKGROUND ART
Liquid crystal devices using liquid crystalline compounds (in the present specification, the term of the liquid crystalline compound is used as a generic name of the compound showing liquid crystal phases and the compound not showing liquid crystal phases but useful as ingredients of the liquid crystal compositions) are broadly used in displays of clocks, watches and electronic calculators, word processors and the like. To these display devices, an optical anisotropy, a dielectric anisotropy and the like of the liquid crystalline compound are applied.
As the liquid crystal phases, a nematic liquid crystal phase, a smectic liquid crystal phase, and a cholesteric liquid crystal phase are used, and particularly, the nematic liquid crystal phase is broadly utilized. As display modes, there are a dynamic scatter (DS) type, a deformation type of an aligning phase (DAP), a guest/host (GH) type, a twisted nematic (TN) type, a super twisted nematic (STN) type, a thin film transistor (TFT) type and the like.
Although the liquid crystalline compounds used in these display modes must show liquid crystal phases at broad temperature ranges, mainly at room temperature, they must be sufficiently stable under conditions that the display devices are used, and they must have characteristics enough to drive the display devices, a single liquid crystalline compound satisfying these conditions is still not found. For these reasons, a few kinds or several tens of kinds of liquid crystalline compounds are conventionally mixed to prepare the liquid crystal compositions satisfying desired properties. It is required that these liquid crystal compositions are stable to moisture, light, heat and air which exist in normal conditions using the display devices, stable to electric field and electromagnetic radiation, and chemically stable to mixed compounds. Further, it is required that these liquid crystal compositions show proper valuer physical properties such as a refractive index anisotropy value (&Dgr; n) and a dielectric anisotropy value (&Dgr; &egr;) of the liquid crystal compositions dictate the display modes or the forms of the display devices. Further, it is important that each ingredient of these liquid crystal compositions has mutually good solubility.
In recent years, various environment using the liquid crystal devices requires the liquid crystal compositions showing liquid crystal phases at a higher temperature. To achieve the requirement, the ingredient may be constituted from the compounds having high transition temperature of an isotropic phase. Such compounds are known from the compounds represented by formula (a) of Japanese Patent Publication No. 62-46527 and formula (b) of Japanese patent Publication No. 4-28693.
These compounds have a high transition temperature of an isotropic phase and relatively low viscosity, but the compounds have problems that the compatibility with the other ingredients in the composition is not enough, so that the compounds should be used in limited amounts.
Objects of the present invention are to solve the problems of the above conventional techniques, and to provide liquid crystalline compounds having excellent compatibility with the other liquid crystal materials and stability, low viscosity, and a high transition temperature of an isotropic phase; liquid crystal compositions comprising the compounds and liquid crystal devices constituted by using the liquid crystal compositions.
DISCLOSURE OF INVENTION
For achieving the above objects, the present invention is as follows.
(1) A liquid crystalline compound which is represented by general formula (1):
R—A
1
—Z
1
—A
2
—Z
2
—A
3
—Z
3
—A
4
—(CH
2
)
m
.X (1)
wherein R indicates H or an alkyl group having 1 to 10 carbon atoms (one or more methylene groups (—CH
2
—) in the alkyl group may be replaced by —O—, —S—, —CO—, —CH═CH— or —C≡C—, but —O— or —S— are not continuous), m indicates an integer of 1 to 10; X indicates F, Cl, Br, I or OH; A
1
, A
2
, A
3
and A
4
, each independently, indicate a trans-1,4-cyclohexylene group, a 1,4-phenylene group in which one or more hydrogen atoms on the ring may be substituted by a fluorine atom, a cyclohexenylenediyl group, a pyrimidine-2,5-diyl group, a pyridine-2,5-diyl group or a 1,3-dioxane-2,5-diyl group; Z
1
, Z
2
and Z
3
, each independently, indicate —(CH
2
)
2
— or a covalent bond, and at least two of Z
1
, Z
2
and Z
3
indicate covalent bonds.
(2) A liquid crystalline compound according to (1), wherein X is F.
(3) A liquid crystalline compound according to (1), wherein X is OH.
(4) A liquid crystalline compound according to (2), wherein Z
1
, Z
2
and Z
3
are covalent bonds.
(5) A liquid crystalline compound according to (2), wherein Z
1
is —(CH
2
)
2
—.
(6) A liquid crystalline compound according to (2), wherein Z
2
is —(CH
2
)
2
—.
(7) A liquid crystalline compound according to (2), wherein Z
3
is -(CH
2
)2-.
(8) A liquid crystalline compound according to (4), wherein both A
1
and A
4
are the trans 1,4-cyclohexylene group, and both A
2
and A
3
are the 1,4-phenylene group in which one or more hydrogen atoms on the ring may be substituted by a fluorine atom.
(9) A liquid crystalline compound according to (4), wherein both A
1
and A
2
are the 1,4-phenylene group in which one or more hydrogen atoms on the ring may be substituted by a fluorine atom, and both A
3
and A
4
are the trans 1,4-cyclohexylene group.
(10) A liquid crystalline compound according to (6), wherein both A
1
and A
2
are the 1,4-phenylene group in which one or more hydrogen atoms on the ring may be substituted by a fluorine atom, and both A
3
and A
4
are the trans 1,4-cyclohexylene group.
(11) A liquid crystal composition comprising at least one of liquid crystalline compounds according to any one of (1) to (10).
(12) A liquid crystal composition, characterized in that it comprises as the first constituent at least one compound selected from the group consisting of the liquid crystalline compounds described in any one of (1) to (10), and as the second constituent at least one compound selected from the group consisting of the compounds represented by general formulas (2), (3) and (4):
wherein R
1
indicates an alkyl group having 1 to 10 carbon atoms; X
1
indicates F, Cl, OCF
3
, OCF
2
H, CF
3
, CF
2
H or CFH
2
; L
1
, L
2
, L
3
and L
4
, each independently indicate H or F; Z
4
and Z
5
, each independently indicate —(CH
2
)
2
—, —CH═CH— or a covalent bond, and a indicates 1 or 2.
(13) A liquid crystal composition, characterized in that it comprises as the first constituent at least one compound selected from the group consisting of the liquid crystalline compounds described in any one of (1) to (10), and as the second constituent at least one compound selected from the group consisting of the compounds represented by general formulas (5), (6), (7), (8) and (9):
wherein R
2
indicates F, an alkyl group having 1 to 10 carbon atoms or an alkenyl group having 2 to 10 carbon atoms; any methylene group (—CH
2
—) in the alkyl group or the alkenyl group may be replaced by an oxygen atom(—O—), but two or more methylene groups are not continuously replaced by the oxygen atom; ring A indicates a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a 1,3-dioxane-2,5-diyl group; ring B indicates a trans-1,4-cyclohexylene group, a 1,4-phenylene group or a pyrimidine-2,5-diyl group; ring C indicates a trans-1,4-cyclohexylene group or a 1,4-phenylene group; Z
6
indicates —(CH
2
)
2
—, —COO— or a covalent bond; L
5
and L
6
, each independently, indicate H or F; and b and c, each independently, indicate 0 or 1,
wherein R
3
indicates an alkyl group having 1 to 10 carbon atoms, L
7
in
Hachiya Norihisa
Kondo Tomoyuki
Matsui Shuichi
Miyazawa Kazutoshi
Nakagawa Etsuo
Browdy & Neimark
Chisso Corporation
Kelly C. H.
LandOfFree
Liquid crystal compounds having substituted alkyl groups,... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Liquid crystal compounds having substituted alkyl groups,..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Liquid crystal compounds having substituted alkyl groups,... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2492259