Liquid crystal device and liquid crystal apparatus

Claim 2

A liquid crystal device, comprising: a first substrate and a second substrate disposed opposite to each other, and a liquid crystal lacking cholesteric phase disposed between the first and second substrates; said first substrate having a surface contacting the liquid crystal showing a surface energy γ 1 (dyne/cm) and said second substrate having a surface contacting the liquid crystal showing a surface energy γ 2 (dyne/cm) satisfying γ 1 >γ 2 ; said first substrate comprising a surface film of a polyimide or an aromatic polyamide, the surface of said first substrate having been selectively subjected to a uniaxial aligning treatment.

Claim 3

A liquid crystal device according to claim 1, wherein γ 1 ≧40 (dyne/cm).

Claim 4

A liquid crystal device according to claim 1, wherein γ 1 ≧45 (dyne/cm).

Claim 5

A liquid crystal device according to claim 1, wherein said uniaxial aligning treatment comprises rubbing.

Claim 6

A liquid crystal device according to claim 4, wherein said rubbing has been effected in both a forward direction and a direction substantially reverse to the forward direction.

Claim 7

A liquid crystal device according to claim 1, wherein γ 1 -γ 2 >9 (dyne/cm).

Claim 8

A liquid crystal device according to claim 1, wherein γ 1 -γ 2 >17 (dyne/cm).

Claim 9

A liquid crystal device according to claim 1, wherein said liquid crystal comprises at least one mesomorphic compound lacking cholesteric phase and a compound (a) having a solubility limit with said at least one mesomorphic compound added in a proportion of at least 20% of and below the solubility limit.

Claim 10

A liquid crystal device according to claim 1, wherein said liquid crystal lacking cholesteric phase comprises at least one species of compounds represented by the following formula (I): P--Q--A--W--B--(T--D).sub.n --U--V (I), wherein A, B and D independently denote an aromatic ring, a heterocyclic ring, an alicyclic ring, or a condensed ring structure thereof, each capable of having a substituent: Q, W and T independently denote a single bond, --O--, --COO--, --OCO--, --C.tbd.C--, --CONR--, --NRCO--, --NR--, --CH 2 --, --CH═N--, --N═CH--, --CH═CH--, --COS--, --SCO--, --CH 2 CH 2 --, --CH 2 O-- or --OCH 2 --, wherein R denotes an alkyl group; P denotes an alkyl group capable of having a substituent; n denotes 0, 1 or 2; U denotes --CO--C m H 2m --, --O--C m H 2m --, --C m H 2m CO--, --C m H 2m O--, --C m H 2m --, --OSO 2 --, --SO 2 O--, --SO 2 --, --SO 2 --C m H 2m --, --O--C m H 2m --O--C m H 2m --, --C m H 2m SO 2 --, --C m H 2m --O--C m H 2m --O--, --C m H 2m --N(C m' H 2m'+1 )--SO 2 --, --C m H 2m --N(C m' H 2m'+1 )--CO--, --SO 2 --N(C m' H 2m'+1 )--C m H 2m -- or --CO--N(C m' H 2m'+1 )--C m H 2m --, wherein m and m' independently denote an integer of 1 to 20; V denotes --(C p F 2p O) q C r F 2r+1 , wherein q is an integer of 1-6; p is an integer of 1-10 which can be independently set where q is plural, and r is an integer of 1-10.

Claim 11

A liquid crystal device according to claim 9, wherein said liquid crystal further includes a compound (a) having a solubility limit with said at least one species of compounds represented by the formula (I) in a proportion of at least 20% of and below the solubility limit.

Claim 12

A liquid crystal device according to claim 8, wherein said compound (a) is an achiral compound having a core part comprising a substituted or unsubstituted aliphatic ring, aromatic ring, a heterocyclic ring or condensed ring structure of these or a combination of these with a bonding group or a single bond; and an unsubstituted alkyl group or a substituted alkyl group free from perfluoro-substitution connected to one or both ends of the core part via a bonding group or a single bond.

Claim 13

A liquid crystal device according to claim 8, wherein said compound (a) has a melting enthalpy of at least 25 J/g.

Claim 14

A liquid crystal device according to claim 8, wherein said compound (a) has an isotropic-liquid crystal phase transition temperature or isotropic-crystal phase transition temperature which is higher than an isotropic-smectic A phase transition temperature of said at least one mesomorphic compound lacking cholesteric phase.

Claim 15

A liquid crystal device according to claim 8, wherein said compound (a) is added in a proportion of at least 40% of and below the solubility limit.

Claim 16

A liquid crystal device according to claim 1, wherein said liquid crystal is a chiral smectic liquid crystal.

Claim 17

A liquid crystal device according to claim 1, wherein said liquid crystal is a ferroelectric liquid crystal.

Claim 18

A liquid crystal device according to claim 1, wherein the surface of said first substrate comprises a film of a polyimide represented by the following general formula (II): ##STR20## wherein K denotes ##STR21## L 1 and L 2 respectively denote ##STR22## M 1 denotes a single bond or --O--; and a denotes 0, 1 or 2.

Claim 19

A liquid crystal apparatus, comprising a liquid crystal device according to claim 1, and means for driving the liquid crystal device.

Claim 20

A liquid crystal device according to claim 1, wherein said liquid crystal is aligned to form a bookshelf structure.

Claim 21

A liquid crystal device according to claim 1, wherein said surface film on said first substrate is a polyimide formed from a diamine and a tetracarboxylic acid having an aromatic ring.

Claim 22

A liquid crystal device according to claim 9, wherein said liquid crystal is aligned to form a bookshelf structure.

Claim 23

A liquid crystal device according to claim 9, wherein said surface film on said first substrate is a polyimide formed from a diamine and a tetracarboxylic acid having an aromatic ring.

Claim 24

A process for producing a liquid crystal device of the type comprising a first substrate and a second substrate disposed opposite to each other, and a liquid crystal lacking cholesteric phase disposed between the first and second substrates; said process including the steps of: forming a film of a polyimide or an aromatic polyamide on a surface contacting the liquid crystal of at least said first substrate; and subjecting said film to a uniaxial aligning treatment such that said first surface of said first substrate contacting said liquid crystal has a surface energy γ 1 (dyne/cm), wherein said second substrate has a surface contacting the liquid crystal has a surface energy γ 2 (dyne/cm) satisfying γ 1 >γ 2 .

Claim 25

A process for producing a liquid crystal device of the type comprising a first substrate and a second substrate disposed opposite to each other, and a liquid crystal lacking cholesteric phase disposed between the first and second substrates; said process including the steps of: forming a film of a polyimide or an aromatic polyamide on a surface contacting the liquid crystal of at least said first substrate; and subjecting said film to a uniaxial aligning treatment such that said first surface of said first substrate contacting said liquid crystal has a surface energy γ 1 (dyne/cm), wherein said second substrate has a surface contacting the liquid crystal has a surface energy γ 2 (dyne/cm) satisfying γ 1 >γ 2 .

Claim 26

A process according to claim 23, wherein said uniaxial aligning treatment comprises rubbing.

Claim 27

A process according to claim 23, wherein the liquid crystal contacting the surfaces of the first and second substrates is aligned to form a bookshelf structure.